449 results on '"E Saitoh"'
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2. Gate-tunable resistance drops related to local superconducting gaps in thin TaS2 layers on SrTiO3 substrates
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M. Kosugi, R. Obata, K. Suzuki, K. Kuroyama, S. Du, B. Skinner, T. Kikkawa, T. Yokouchi, Y. Shiomi, S. Maruyama, K. Hirakawa, E. Saitoh, and J. Haruyama
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Biotechnology ,TP248.13-248.65 ,Physics ,QC1-999 - Abstract
Strontium titanate [SrTiO3 (STO)], a perovskite oxide with an extremely high gate-tunable dielectric constant (ε) due to quantum paraelectric phases, is attracting considerable attention for yielding various physical phenomena when two-dimensional (2D) layers are integrated. Superconductivity is such a typical phenomenon. However, the influence of the STO substrates on enhancing transition temperatures (Tc) for (atomically) thin 2D flakes attached to them has been rarely investigated. Here, we report gate-tunable and gradual four-terminal resistance drops with critical onset T (TCR) and scanning tunneling spectroscopy (STS) spectra in devices comprising thin TaS2 flakes attached on monolayer hexagonal boron nitride (hBN) spacer/STO substrates. Observation of STS spectra confirms the presence of local superconducting gaps Δ (∼1.5 meV) with transition T (TΔC) three-times higher than previous reports of Tc under absent pressure and strong position dependence of Δ. Depending on Δ on back gate voltages (Vbg) and magnetic fields, there is a strong correlation between TCR and the onset Tc of superconductivity, implying an enhancement of approximately five times compared with the previous highest-onset Tc values without pressure as the applied Vbg increases. The high onset Tc and Δ are discussed based on screening of the long-range Coulomb interaction (CI) due to the high-ε of SrTiO3, while the short-ranged CI remains strong in the 2D limit, causing the superconductivity. Using a monolayer hBN/SrTiO3 substrate with Vbg opens doors to Tc enhancement in thin superconducting layers integrated on it and wide application due to the solid-state high-ε substrates.
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- 2023
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3. Observation of nuclear-spin Seebeck effect
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T. Kikkawa, D. Reitz, H. Ito, T. Makiuchi, T. Sugimoto, K. Tsunekawa, S. Daimon, K. Oyanagi, R. Ramos, S. Takahashi, Y. Shiomi, Y. Tserkovnyak, and E. Saitoh
- Subjects
Science - Abstract
Thermoelectric effects are limited to electrons to occur, and disappear at low temperatures due to electronic entropy quenching. Here, the authors report thermoelectric generation caused by nuclear spins down to 100 mK due to nuclear-spin excitation in a magnetically ordered material MnCO3.
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- 2021
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4. Giant spin hydrodynamic generation in laminar flow
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R. Takahashi, H. Chudo, M. Matsuo, K. Harii, Y. Ohnuma, S. Maekawa, and E. Saitoh
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Science - Abstract
In spin hydrodynamic generation originating from the coupling of mechanical rotation in a fluid and electron spin, fluid vorticity can be converted into an electric voltage via a spin current. Here, the authors demonstrate experimentally that the energy conversion in a laminar flow regime is strongly enhanced over the turbulent regime.
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- 2020
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5. Electric current control of spin helicity in an itinerant helimagnet
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N. Jiang, Y. Nii, H. Arisawa, E. Saitoh, and Y. Onose
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Science - Abstract
The spin helicity in helimagnets may be exploited in magnetic memory applications if electrically controllable and detectable. Here, helicity manipulation driven by an electric current and detection by second harmonic resistivity measurements in an itinerant helimagnet MnP is demonstrated.
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- 2020
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6. Coherent ac spin current transmission across an antiferromagnetic CoO insulator
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Q. Li, M. Yang, C. Klewe, P. Shafer, A. T. N’Diaye, D. Hou, T. Y. Wang, N. Gao, E. Saitoh, C. Hwang, R. J. Hicken, J. Li, E. Arenholz, and Z. Q. Qiu
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Science - Abstract
The mechanism underpinning the frequency mismatch between THz magnons and the GHz spin currents observed in antiferromagnetic insulators remains unknown. Here, the authors demonstrate that, in a Py/Ag/CoO/Ag/Fe75Co25/MgO(001) heterostructure, a GHz spin current transmits coherently across the antiferromagnetic CoO insulating layer to drive a coherent spin precession of the ferromagnetic Fe75Co25 layer.
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- 2019
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7. Room temperature and low-field resonant enhancement of spin Seebeck effect in partially compensated magnets
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R. Ramos, T. Hioki, Y. Hashimoto, T. Kikkawa, P. Frey, A. J. E. Kreil, V. I. Vasyuchka, A. A. Serga, B. Hillebrands, and E. Saitoh
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Science - Abstract
The spin Seebeck effect (SSE) converts thermally induced magnetization dynamics in magnetic materials to spin currents, but is so far an inefficient process. Here, the authors achieved resonant enhancement of the SSE voltage 700% larger than previously observed in Y3Fe5O12 by tuning the magnon lifetime via doping in $${{\rm{Lu}}}_{2}{{\rm{BiFe}}}_{4}{{\rm{GaO}}}_{12}$$ Lu2BiFe4GaO12 .
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- 2019
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8. Vortex rectenna powered by environmental fluctuations
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J. Lustikova, Y. Shiomi, N. Yokoi, N. Kabeya, N. Kimura, K. Ienaga, S. Kaneko, S. Okuma, S. Takahashi, and E. Saitoh
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Science - Abstract
Devices that generate electricity from electric fluctuations are promising for wireless power transmission as well as energy harvesting from environmental radio waves. Here the authors report the electric power generation from environmental fluctuations by using superconducting vortex strings in MoGe/YIG bilayer system.
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- 2018
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9. Oscillatory Nernst effect in Pt|ferrite|cuprate-superconductor trilayer films
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Y. Shiomi, J. Lustikova, and E. Saitoh
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Medicine ,Science - Abstract
Abstract Although magnetism and superconductivity hardly coexist in a single material, recent advances in nanotechnology and spintronics have brought to light their interplay in magnetotransport in thin-film heterostructures. Here, we found a periodic oscillation of Nernst voltage with respect to magnetic fields in Pt|LiFe5O8 (Pt|LFO) bilayers grown on a cuprate superconductor YBa2Cu3O7−x (YBCO). At high temperatures above the superconducting transition temperature (T C ) of YBCO, spin Seebeck voltages originating in Pt|LFO layers are observed. As temperature decreases well below T C , the spin Seebeck voltage is suppressed and unconventional periodic voltage oscillation as a function of magnetic fields appears; such an oscillation emerging along the Hall direction in the superconducting state has not been observed yet. Dynamics of superconducting vortices pinned by surface precipitates seems responsible for the oscillatory Nernst effect.
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- 2017
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10. Observation of temperature-gradient-induced magnetization
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Dazhi Hou, Zhiyong Qiu, R. Iguchi, K. Sato, E. K. Vehstedt, K. Uchida, G. E. W. Bauer, and E. Saitoh
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Science - Abstract
In general, heating increases disorder and leads to the loss of magnetism in condensed matter. Here, the authors demonstrate that a normal metal can be magnetized by applying a temperature gradient during non-uniform heating when attached to a magnetic insulator.
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- 2016
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11. Electric field effect on magnetic anisotropy for Fe-Pt-Pd alloys
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S. Kikushima, T. Seki, K. Uchida, E. Saitoh, and K. Takanashi
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Physics ,QC1-999 - Abstract
The electric field effect on magnetic anisotropy was investigated for the FePt1-xPdx alloy films with perpendicular magnetic anisotropy. The polar magneto-optical Kerr (p-MOKE) loops were measured under the electric field application in order to evaluate the electric field-induced perpendicular magnetic anisotropy change per area (Δεperpt). A clear change in the saturation field of p-MOKE loop was observed for FePt by varying the applied electric field (ΔE). In the case of FePt, Δεperpt divided by ΔE was evaluated to be -129 (fJ/Vm). We found that the magnitude of Δεperpt / ΔE was significantly reduced with increasing x.
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- 2017
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12. Temperature dependence of the spin Seebeck effect in [Fe3O4/Pt]n multilayers
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R. Ramos, T. Kikkawa, A. Anadón, I. Lucas, K. Uchida, P. A. Algarabel, L. Morellón, M. H. Aguirre, E. Saitoh, and M. R. Ibarra
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Physics ,QC1-999 - Abstract
We report temperature dependent measurements of the spin Seebeck effect (SSE) in multilayers formed by repeated growth of a Fe3O4/Pt bilayer junction. The magnitude of the observed enhancement of the SSE, relative to the SSE in the single bilayer, shows a monotonic increase with decreasing the temperature. This result can be understood by an increase of the characteristic length for spin current transport in the system, in qualitative agreement with the recently observed increase in the magnon diffusion length in Fe3O4 at lower temperatures. Our result suggests that the thermoelectric performance of the SSE in multilayer structures can be further improved by careful choice of materials with suitable spin transport properties.
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- 2017
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13. Linear magnetoresistance in a topological insulator Ru2Sn3
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Y. Shiomi and E. Saitoh
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Physics ,QC1-999 - Abstract
We have studied magnetotransport properties of a topological insulator material Ru2Sn3. Bulk single crystals of Ru2Sn3 were grown by a Bi flux method. The resistivity is semiconducting at high temperatures above 160 K, while it becomes metallic below 160 K. Nonlinear field dependence of Hall resistivity in the metallic region shows conduction of multiple carriers at low temperatures. In the high-temperature semiconducting region, magnetoresistance exhibits a conventional quadratic magnetic-field dependence. In the low-temperature metallic region, however, high-field magnetoresistance is clearly linear with magnetic fields, signaling a linear dispersion in the low-temperature electronic structure. Small changes in the magnetoresistance magnitude with respect to the magnetic field angle indicate that bulk electron carriers are responsible mainly for the observed linear magnetoresistance.
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- 2017
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14. Spin Seebeck effect in insulating epitaxial γ−Fe2O3 thin films
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P. Jiménez-Cavero, I. Lucas, A. Anadón, R. Ramos, T. Niizeki, M. H. Aguirre, P. A. Algarabel, K. Uchida, M. R. Ibarra, E. Saitoh, and L. Morellón
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Biotechnology ,TP248.13-248.65 ,Physics ,QC1-999 - Abstract
We report the fabrication of high crystal quality epitaxial thin films of maghemite (γ−Fe2O3), a classic ferrimagnetic insulating iron oxide. Spin Seebeck effect (SSE) measurements in γ−Fe2O3/Pt bilayers as a function of sample preparation conditions and temperature yield a SSE coefficient of 0.5(1) μV/K at room temperature. Dependence on temperature allows us to estimate the magnon diffusion length in maghemite to be in the range of tens of nanometers, in good agreement with that of conducting iron oxide magnetite (Fe3O4), establishing the relevance of spin currents of magnonic origin in magnetic iron oxides.
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- 2017
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15. Thermoelectric performance of spin Seebeck effect in Fe3O4/Pt-based thin film heterostructures
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R. Ramos, A. Anadón, I. Lucas, K. Uchida, P. A. Algarabel, L. Morellón, M. H. Aguirre, E. Saitoh, and M. R. Ibarra
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Biotechnology ,TP248.13-248.65 ,Physics ,QC1-999 - Abstract
We report a systematic study on the thermoelectric performance of spin Seebeck devices based on Fe3O4/Pt junction systems. We explore two types of device geometries: a spin Hall thermopile and spin Seebeck multilayer structures. The spin Hall thermopile increases the sensitivity of the spin Seebeck effect, while the increase in the sample internal resistance has a detrimental effect on the output power. We found that the spin Seebeck multilayers can overcome this limitation since the multilayers exhibit the enhancement of the thermoelectric voltage and the reduction of the internal resistance simultaneously, therefore resulting in significant power enhancement. This result demonstrates that the multilayer structures are useful for improving the thermoelectric performance of the spin Seebeck effect.
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- 2016
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16. Modulation of Spin Seebeck Effect by Hydrogenation
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K. Ogata, T. Kikkawa, E. Saitoh, and Y. Shiomi
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Condensed Matter - Materials Science ,Condensed Matter - Mesoscale and Nanoscale Physics ,Physics and Astronomy (miscellaneous) ,Mesoscale and Nanoscale Physics (cond-mat.mes-hall) ,Materials Science (cond-mat.mtrl-sci) ,FOS: Physical sciences - Abstract
We demonstrate the modulation of spin Seebeck effect (SSE) by hydrogenation in Pd/YIG bilayers. In the presence of 3% hydrogen gas, SSE voltage decreases by more than 50% from the magnitude observed in pure Ar gas. The modulation of the SSE voltage is reversible, but the recovery of the SSE voltage to the prehydrogenation value takes a few days because of a long time constant of hydrogen desorption. We also demonstrate that the spin Hall magnetoresistance of the identical sample reduces significantly with hydrogen exposure, supporting that the observed modulation of spin current signals originates from hydrogenation of Pd/YIG.
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- 2022
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17. Magnetic sensitivity distribution of Hall devices in antiferromagnetic switching experiments
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F. Schreiber, H. Meer, C. Schmitt, R. Ramos, E. Saitoh, L. Baldrati, and M. Kläui
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Condensed Matter - Materials Science ,Condensed Matter - Mesoscale and Nanoscale Physics ,530 Physics ,General Physics and Astronomy ,Materials Science (cond-mat.mtrl-sci) ,FOS: Physical sciences ,02 engineering and technology ,021001 nanoscience & nanotechnology ,530 Physik ,01 natural sciences ,0103 physical sciences ,Mesoscale and Nanoscale Physics (cond-mat.mes-hall) ,Condensed Matter::Strongly Correlated Electrons ,010306 general physics ,0210 nano-technology - Abstract
We analyze the complex impact of the local magnetic spin texture on the transverse Hall-type voltage in device structures utilized to measure magnetoresistance effects. We find a highly localized and asymmetric magnetic sensitivity in the eight-terminal geometries that are frequently used in current-induced switching experiments, for instance to probe antiferromagnetic materials. Using current-induced switching of antiferromagnetic NiO/Pt as an example, we estimate the change in the spin Hall magnetoresistance signal associated with switching events based on the domain switching patterns observed via direct imaging. This estimate correlates with the actual electrical data after subtraction of a non-magnetic contribution. Here, the consistency of the correlation across three measurement geometries with fundamentally different switching patterns strongly indicates a magnetic origin of the measured and analyzed electrical signals.
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- 2022
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18. Spin-current injection and detection in κ-(BEDT-TTF)2Cu[N(CN)2]Br
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Z. Qiu, M. Uruichi, D. Hou, K. Uchida, H. M. Yamamoto, and E. Saitoh
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Physics ,QC1-999 - Abstract
Spin-current injection into an organic semiconductor κ-(BEDT-TTF)2Cu[N(CN)2]Br film induced by the spin pumping from an yttrium iron garnet (YIG) film. When magnetization dynamics in the YIG film is excited by ferromagnetic or spin-wave resonance, a voltage signal was found to appear in the κ-(BEDT-TTF)2Cu[N(CN)2]Br film. Magnetic-field-angle dependence measurements indicate that the voltage signal is governed by the inverse spin Hall effect in κ-(BEDT-TTF)2Cu[N(CN)2]Br. We found that the voltage signal in the κ-(BEDT-TTF)2Cu[N(CN)2]Br/YIG system is critically suppressed around 80 K, around which magnetic and/or glass transitions occur, implying that the efficiency of the spin-current injection is suppressed by fluctuations which critically enhanced near the transitions.
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- 2015
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19. Identification of Néel Vector Orientation in Antiferromagnetic Domains Switched by Currents in Ni O / Pt Thin Films
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C. Schmitt, L. Baldrati, L. Sanchez-Tejerina, F. Schreiber, A. Ross, M. Filianina, S. Ding, F. Fuhrmann, R. Ramos, F. Maccherozzi, D. Backes, M.-A. Mawass, F. Kronast, S. Valencia, E. Saitoh, G. Finocchio, M. Kläui
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- 2021
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20. Spatiotemporal treadmill gait measurements using a laser range scanner: feasibility study of the healthy young adults
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S Tanabe, T Ii, S Koyama, E Saitoh, N Itoh, K Ohtsuka, Y Katoh, A Shimizu, and Y Tomita
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Adult ,Male ,030506 rehabilitation ,Scanner ,Physiology ,Computer science ,Biomedical Engineering ,Biophysics ,Motion capture ,law.invention ,Young Adult ,03 medical and health sciences ,Spatio-Temporal Analysis ,0302 clinical medicine ,Gait (human) ,Position (vector) ,law ,Physiology (medical) ,Range (statistics) ,Humans ,Treadmill ,Gait ,Simulation ,Lasers ,Laser ,Healthy Volunteers ,Gait analysis ,Exercise Test ,Feasibility Studies ,Female ,0305 other medical science ,030217 neurology & neurosurgery - Abstract
Objective: Spatio-temporal parameters are typically used for gait analysis. Although these parameters are measured by sophisticated systems such as 3D motion capture system or optoelectronic bars, these systems cannot be deployed easily because of their high costs, large space requirements and elaborate set-up. The purpose of this study is to develope a system for measuring spatiotemporal gait parameters using a laser range scanner during treadmill gait. Approach: To calculate accurate spatiotemporal parameters, the differences between the laser range scanner measured values and the reference values obtained from a 3D motion capture system were investigated in thirty subjects. From measurements in time and position at foot contact/off, adjustments to compensate for the differences in time and position were derived. Then, to determine the validity of the proposed system, values from the proposed system and the reference system were compared in four additional subjects. Main results: The results indicate that the data from the laser range scanner demonstrate certain differences in time and position compared with reference values. However, when compensation values were introduced, each spatiotemporal parameter correlated well with the reference values. Significance: This newer system is smaller, is easier to deploy and requires less training than the 3D motion capture system.
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- 2017
21. EP629 Two young patients with endometrial cancer who newly developed double cancer in their ovaries after endometrial tumor disappearance through high-dose progesterone therapy and endometrial curettage
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N Susumu, E Saitoh, and S Ikeda
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medicine.medical_specialty ,Hysterectomy ,business.industry ,medicine.medical_treatment ,Endometrial cancer ,Uterus ,Urology ,medicine.disease ,Curettage ,medicine.anatomical_structure ,medicine ,Carcinoma ,Medroxyprogesterone acetate ,Ovarian cancer ,business ,Atypical Endometrial Hyperplasia ,medicine.drug - Abstract
Introduction/Background Standard treatment for endometrial cancer (EC) and atypical endometrial hyperplasia (AEH) is total hysterectomy and bilateral salpingo-oophorectomy (BSO), however, young patients with early-stage EC and AEH in reproductive age often hope to preserve their fertility. The oncologic outcomes in long follow-up remain unclear especially regarding the incidences of recurrence or double cancer. We experienced two patients with EC who newly developed double cancer in their ovaries after medication of high-dose medroxyprogesterone acetate (MPA) for fertility-preservation. Methodology In principle, we survey the patients after MPA therapy every four months using vaginal ultrasound check, endometrial histological/cytological examinations, measurement of serum CA125, and pelvic MRI once a year. Results The 44 y/0 patient had received MPA therapy and cyclic surveillance every 4 to 6 months in the previous hospital, and she was introduced to our hospital with 3 year-recurrence-free interval. However, trans-vaginal (TV) echo showed solid tumor measuring 18 mm in diameter in the right ovary, and the serum CA125 was 32 U/ml. MRI revealed solid tumor with positive Gd-enhancement. Hysterectomy with RSO and LS were performed. Pathological examination revealed endometrioid carcinoma (EMC) G1 in uterus (pT1A), and mucin-producing EMC G1 in the right ovary (pT1A, primary ovarian cancer). Another 38 y/o patient had finished MPA therapy 4 months before. TV echo showed solid tumors measuring 30 mm in both ovaries, and the serum CA125 was 112 U/ml. MRI revealed solid tumors in both ovaries with positive Gd-enhancement. Hysterectomy with BSO, retroperitoneal lymphadenectomy was performed. Pathological examination revealed EMC G1 in uterus (pT1A), and mucin-producing EMC G2 in both ovaries (pT1B, bilateral primary ovarian cancers). Both patients have no recurrence after operation without adjuvant chemotherapy for 12 months. Conclusion Strictly careful follow-up every 4 months using TV echo and CA125 is needed after fertility-preserving MPA therapy for detecting heterochronous overlapping cancers in ovaries. Disclosure Nothing to disclose.
- Published
- 2019
22. Double-contrast tongue surface imaging technique in swallowing computed tomography
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D, Kanamori, primary, N, Fujii, additional, Y, Inamoto, additional, K, Aihara, additional, M, Kobayashi, additional, Y, Aoyagi, additional, K, Matsuo, additional, H, Kagaya, additional, H, Toyama, additional, S, Sonoda, additional, and E, Saitoh, additional
- Published
- 2019
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23. Introduction
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E. Saitoh
- Abstract
This chapter is an introduction to the concept of spin current, the detailed formulation of which is not simple by any means and is still a challenging undertaking. However, it is a useful and versatile concept that has given birth to a number of phenomena in condensed matter science and spintronics. There exist certain types of flow, carried by electrons, in condensed matter. This flow of electron charge or electric current has been developed and is now a vital contributor to how electronics is understood today. Since an electron carries both charge and spin, the existence of an electric current naturally implies the existence of a flow of spin. This flow is called a spin current.
- Published
- 2017
24. Spin-Mechatronics—mechanical generation of spin and spin current
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M. Matsuo, E. Saitoh, and S. Maekawa
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Condensed Matter::Strongly Correlated Electrons - Abstract
This chapter discusses interconversion phenomena between spin and mechanical angular momtum. In moving objects, the spin gauge fields emerge from inertial effects and produce angular momentum transfer between mechanical motion and spin. Such spin-mechanial effects are predicted by quantum theory in non-inertial frames, and confirmed by recent experiments including the resonance frequency shift in NMR, the stray field measurement of rotating metals, and the inverse spin Hall voltage generation in liquied metals. These spin-mechanical effects that arise via the spin-gauge fields open a new field of spintornics, where spin and mechanical motion couple harmoniously.
- Published
- 2017
25. Topological spin current
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E. Saitoh
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Condensed Matter::Strongly Correlated Electrons - Abstract
This chapter discusses another type of equilibrium-spin current similar to the exchange-spin current—the topological spin current. Topological spin currents are driven by topological-band structure and classified into bulk and surface topological spin currents. The former is confined onto electron-band manifolds, sometimes affecting their motions. This confinement is addressed through the standard method of combining the equations of motion and the Boltzmann equation for semi-classical electrons in a band. The latter class, on the other hand, is a surface-spin current, which is limited near surfaces of a three-dimensional system and flows along these surfaces. This type is known to appear in topological insulators, where the bulk is insulating but the surface or edge is electrically conducting due to the surface or edge state.
- Published
- 2017
26. Magnetic Domain Wall Manipulation Using MFM Probe
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Hideki Miyajima, K. Watanabe, E. Saitoh, Takehiro Yamaoka, Masaaki Tanaka, Yoshiharu Shirakawabe, and K. Machida
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Physics ,Permalloy ,Magnetic domain ,Condensed matter physics ,Moment (physics) ,Electrical and Electronic Engineering ,Magnetic force microscope ,Condensed Matter Physics ,Instrumentation ,Signal ,Electronic, Optical and Magnetic Materials - Abstract
Magnetic force microscopy (MFM) has been applied to permalloy multistep-semicircular wires containing nearly-free magnetic domain walls (DWs). In this study, we investigated the effect of stray-magnetic fields from the probes in the MFM measurement using low-, medium-, and high-moment probes, which are coated by 12 nm-, 24 nm-, and 72 nm-thick CoPtCr films, respectively. By using the low-moment probe, the DW signal was clearly observed at the side of the wires, which is consistent with a micromagnetic simulation. By using the high and medium moment probes, in contrast, we observed complete and incomplete DW manipulations, respectively. These manipulation signals were found to be maximized immediately above the wire. These phenomena were analyzed by calculating the stray fields from the MFM probes. We also discussed the possibility of the controllable DW manipulation in terms of the stray fields and the MFM scanning sequences.
- Published
- 2007
27. Magnetic Ice-Order in a Permalloy Honeycomb Nano-network
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E. Saitoh, Masaaki Tanaka, Takehiro Yamaoka, Yasuhiro Iye, and Hideki Miyajima
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Permalloy ,Superconductivity ,Materials science ,Condensed matter physics ,Magnetoresistance ,Magnetism ,Exchange interaction ,Condensed Matter Physics ,Electronic, Optical and Magnetic Materials ,Condensed Matter::Materials Science ,Magnetization ,Lattice (order) ,Electrical and Electronic Engineering ,Magnetic force microscope ,Instrumentation - Abstract
Magnetic structures and magnetization processes in a permalloy wire-based honeycomb network were investigated by means of magnetic-force microscopy (MFM) and magnetoresistance measurement. The MFM measurements show that the remanent magnetic structures are governed by a magnetic interaction similar to the ice-rule, which provides a direct analogy between the present honeycomb network and an Ising system on a kagome lattice. The magnetoresistance measurements reveal that the magnetic interaction at the vertexes also dominates the magnetization processes in the network. With a decrease in the exchange energy at the vertices, the ice-rule-type interaction disappears, causing a transition of the magnetization distribution in the network.
- Published
- 2005
28. Current-Voltage Characteristics of Conductance Quantized States in Ferromagnetic Ni Nanowires
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E. Saitoh, Hideki Miyajima, M. Shimizu, and Koji Sekiguchi
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Materials science ,Current voltage ,Condensed matter physics ,Ferromagnetism ,Nanowire ,Conductance ,Electrical and Electronic Engineering ,Condensed Matter Physics ,Instrumentation ,Electronic, Optical and Magnetic Materials - Published
- 2004
29. Development of a Scanning Hall Probe Microscope with High Spatial Resolution
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E. Saitoh, H. Miyajima, M. Shimizu, and H. Masuda
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Physics ,Scanning Hall probe microscope ,business.industry ,Demagnetizing field ,Condensed Matter Physics ,Electronic, Optical and Magnetic Materials ,Magnetic field ,Geomagnetic reversal ,Scanning probe microscopy ,Optics ,Ferromagnetism ,Near-field scanning optical microscope ,Electrical and Electronic Engineering ,Magnetic force microscope ,business ,Instrumentation - Abstract
A scanning Hall probe microscope (SHPM) with high resolution of the magnetic field was developed. The non-magnetic scanning stage allows the sample position to be perfectly controlled even in magnetic fields up to 15 kOe. The stray field distribution at the surface of ferromagnetic SmCo5 was investigated in various external magnetic fields. The observed stray-field images show domain transitions corresponding to the magnetic reversal process.
- Published
- 2004
30. Orbital Wave Excitation in LaMnO3
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E. Saitoh, Kazuyuki Tobe, Yoshinori Tokura, Takashi Kimura, and Kei Takahashi
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Physics ,Condensed matter physics ,Band gap ,Condensed Matter Physics ,Electronic, Optical and Magnetic Materials ,symbols.namesake ,Non-bonding orbital ,symbols ,Condensed Matter::Strongly Correlated Electrons ,Astrophysics::Earth and Planetary Astrophysics ,Electrical and Electronic Engineering ,Ground state ,Raman spectroscopy ,Instrumentation ,Néel temperature ,Orbital magnetization ,Raman scattering ,Excitation - Abstract
Raman scattering was investigated for a single crystal of LaMnO3. In the orbitally ordered ground state, a clear Raman structure between 120 meV and 170 meV appears, which is relevant to the collective excitation of the orbital degree of freedom called “orbital wave.” The intensity of the Raman bands rapidly decreases above the Neel temperature. This indicates that the coherence of the orbital wave is suppressed in the absence of the static spin order. The peak energy of the Raman bands is decreased with increasing temperature toward the orbital order-disorder temperature T∞. The suppression of the Jahn-Teller distortion as well as the energy gap of the orbital excitation near T∞ may be responsible for the observed energy shift.
- Published
- 2002
31. Separate Time Dependences of Conductance Quantization in Ferromagnetic Ni Nano-wire
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E. Saitoh, Hideki Miyajima, Y. Ooka, and M. Shimizu
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Physics ,Condensed matter physics ,Magnetic domain ,Nanowire ,Conductance ,Condensed Matter::Mesoscopic Systems and Quantum Hall Effect ,Condensed Matter Physics ,Electronic, Optical and Magnetic Materials ,Magnetic field ,Quantization (physics) ,Ferromagnetism ,Remanence ,Electrical and Electronic Engineering ,Instrumentation - Abstract
The conductance quantization of Ni Nano-wire was investigated by using break-junction technique. When the width of the nano-wire decreased rapidly, the conductance in remanent magnetization states was observed to be quantized in units of 2e2/h. The unit of quantization switched to e2/h when a magnetic field was applied. When the width of the nano-wire varied slowly, however, quantized conductance plateaus in units of e2/h appeared in the remanent state. Even in this case, the plateaus with ne2/h (n = 2,4,6,...) were observed to be more stable than those with ne2/h (n = 1,3,5,...). The results imply the relevance of the local magnetic domain structrure around the contact, as well as its reconfiguration by the magnetic field, to conductance quantization in ferromagnets.
- Published
- 2002
32. Application of High Volume Fly-Ash Concrete Blocks for the Mounds Coastal Fishing Grounds
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S. Nagataki, E. Saitoh, T. Suzuki, and K. Fukudome
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Hydrology ,Volume (thermodynamics) ,Fly ash ,Fishing ,Environmental science ,Upwelling ,General Materials Science ,Geotechnical engineering - Published
- 2000
33. Experimental observation of the spin Hall effect using spin dynamics
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E. Saitoh and K. Ando
- Published
- 2012
34. Spin Seebeck effect
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E. Saitoh and K. Uchida
- Published
- 2012
35. Incoherent spin current
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K. Ando and E. Saitoh
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- 2012
36. Introduction
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E. Saitoh
- Published
- 2012
37. Exchange spin current
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E. Saitoh and K. Ando
- Published
- 2012
38. Spin Current Generation and Utilization in Metals and Insulators
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E. Saitoh
- Subjects
Materials science ,Spin current ,Engineering physics - Published
- 2011
39. Three-dimensional space-marching method on unstructured grid
- Author
-
Kazuhiro Nakahashi, Dmitri Sharov, and E. Saitoh
- Subjects
Physics ,symbols.namesake ,Active domain ,Mathematical analysis ,symbols ,Choked flow ,Three-dimensional space ,Unstructured grid ,Euler equations - Published
- 2007
40. Spin-current injection and detection in κ-(BEDT-TTF)2Cu[N(CN)2]Br
- Author
-
H. M. Yamamoto, Dazhi Hou, Zhiyong Qiu, E. Saitoh, M. Uruichi, and Ken-ichi Uchida
- Subjects
Spin pumping ,Magnetization dynamics ,Materials science ,Yttrium iron garnet ,General Physics and Astronomy ,Inverse ,Resonance ,lcsh:QC1-999 ,chemistry.chemical_compound ,Crystallography ,chemistry ,Ferromagnetism ,Excited state ,Spin Hall effect ,lcsh:Physics - Abstract
Spin-current injection into an organic semiconductor $\rm{\kappa\text{-}(BEDT\text{-}TTF)_2Cu[N(CN)_2]Br}$ film induced by the spin pumping from an yttrium iron garnet (YIG) film. When magnetization dynamics in the YIG film is excited by ferromagnetic or spin-wave resonance, a voltage signal was found to appear in the $\rm{\kappa\text{-}(BEDT\text{-}TTF)_2Cu[N(CN)_2]Br}$ film. Magnetic-field-angle dependence measurements indicate that the voltage signal is governed by the inverse spin Hall effect in $\rm{\kappa\text{-}(BEDT\text{-}TTF)_2Cu[N(CN)_2]Br}$. We found that the voltage signal in the $\rm{\kappa\text{-}(BEDT\text{-}TTF)_2Cu[N(CN)_2]Br}$/YIG system is critically suppressed around 80 K, around which magnetic and/or glass transitions occur, implying that the efficiency of the spin-current injection is suppressed by fluctuations which critically enhanced near the transitions.
- Published
- 2015
41. Acute lung injury as a possible adverse drug reaction related to gefitinib
- Author
-
M Shibuya, E Saitoh, and R Ieki
- Subjects
Pulmonary and Respiratory Medicine ,Oncology ,Male ,medicine.medical_specialty ,Lung Neoplasms ,Antineoplastic Agents ,Lung injury ,Gefitinib ,Internal medicine ,Carcinoma, Non-Small-Cell Lung ,medicine ,Humans ,heterocyclic compounds ,skin and connective tissue diseases ,Lung cancer ,neoplasms ,Respiratory Distress Syndrome ,medicine.diagnostic_test ,business.industry ,Respiratory disease ,respiratory system ,Middle Aged ,medicine.disease ,Rash ,respiratory tract diseases ,Clinical trial ,Bronchoalveolar lavage ,Immunology ,Quinazolines ,medicine.symptom ,business ,Adverse drug reaction ,medicine.drug - Abstract
Gefitinib is a potent drug used in the treatment of nonsmall-cell lung cancer (NSCLC). Gefitinib acts by inhibition of the epidermal growth factor receptor tyrosine kinase. Clinical trials have confirmed the efficacy of gefitinib for NSCLC. Adverse drug reactions, although frequent, are mild, and include acne-like skin rash and diarrhoea. The present study describes the case of a 56-yr-old male with NSCLC who, 4 weeks after treatment with gefitinib, suffered from a severe alveolar haemorrhage diagnosed by bronchoalveolar lavage. This is the first case report of an acute life-threatening lung injury in a patient with nonsmall-cell lung cancer who had been given gefitinib.
- Published
- 2003
42. Characteristics of F-wave in different stretched positions of the affected arm in patients with cerebrovascular diseases
- Author
-
T, Suzuki, E, Saitoh, S, Daikuya, H, Hirose, M, Tani, R, Nabeta, I, Wakayama, and T, Fujiwara
- Subjects
Adult ,Male ,Reflex, Stretch ,Electromyography ,Muscle Relaxation ,Posture ,Middle Aged ,Paresis ,Treatment Outcome ,Predictive Value of Tests ,Muscle Hypertonia ,Arm ,Reaction Time ,Humans ,Female - Abstract
To investigate the effect of continued stretching of affected arms in patients with cerebrovascular disease (CVD), F-wave was tested from the abductor pollicis brevis (APB) during relaxation (trial 1) and 3 different continued stretches: stretched position with shoulder abduction (trial 2), stretched position with shoulder abduction and elbow extension (trial 3), and stretched position with shoulder abduction, elbow extension and wrist extension (trial 4) of the affected arm for 1 min. in 20 hemiparesis patients with moderate hypertonus (modified Ashworth scale of 2 or 3) caused by CVD (mean age of 49.5 years). Persistence and amplitude ratio of F/M in trial 2 were the same as those in trial 1. Persistence and amplitude ratio of F/M in trials 3 and 4 were significantly lower than those in trial 1. It was suggested that excitability of spinal neural function of the distal part, the APB, of the affected arm was reduced during continued stretching of the proximal part, shoulder and elbow joints, or all of the shoulder, elbow and wrist joints in hemiparesis patients with moderate hypertonus caused by CVD.
- Published
- 2003
43. Characteristic appearances of the H-reflex and F-wave with increased stimulus intensity in patients with cerebrovascular disease
- Author
-
T, Suzuki, E, Saitoh, M, Tani, R, Nabeta, S, Daikuya, H, Hirose, I, Wakayama, and T, Fujiwara
- Subjects
Adult ,Aged, 80 and over ,Male ,Electromyography ,Middle Aged ,Severity of Illness Index ,Electric Stimulation ,H-Reflex ,Paresis ,Tendons ,Cerebrovascular Disorders ,Spinal Nerves ,Arm ,Humans ,Female ,Muscle, Skeletal ,Aged - Abstract
We experienced H-reflex may be evoked with supramaximal stimulation in patients with cerebrovascular disease (CVD). In this study, we investigated the relationship between the characteristic appearances of H-reflex and F-wave with increased stimulus intensity and neurological signs. We examined the H-reflex and F-wave of the affected arm with increased stimulus intensity during muscle relaxation in 31 patients (17 males and 14 females) with hemiparesis caused by CVD. Mean patient age was 56.0 (range 30-82) years. 30 healthy subjects, mean age of 56.2 (range 28-80) were investigated using the same method as controlled group. H-reflex and F-wave with increased stimulus intensity after the median nerve stimulation at the wrist were recorded from the opponence pollicis muscle on the affected side in patients with CVD or right arm in the healthy subjects. Appearance patterns of the H-reflex and F-wave with increased stimulus intensity was separated into four types. Type 1: F-wave appeared with increased stimulus intensity, but there was no H-reflex. Type 2: H-reflex and F-wave both appeared with increased stimulus intensity, but the F-wave followed disappearance of the H-reflex with increased stimulus intensity. Type 3: H-reflex and F-wave both appeared with increased stimulus intensity, but the F-wave appeared during the H-reflex with increased stimulus intensity. Type 4: Only the H-reflex appeared with increased stimulus intensity, but there was no F-wave. Neurological findings including muscle tone and tendon reflex were also evaluated. Findings on muscle tone and tendon reflex were classified into increased (markedly, moderately and slightly), normal and decreased. Results were analyzed as follows; 1) The characteristic appearances of H-reflex and F-wave in the healthy subjects and 2) The relationship between characteristic appearances of waves with increased stimulus intensity and neurological signs in patients with CVD. 1) Pattern of the H-reflex and F-wave with increased stimulus intensity in all healthy subjects were type 1. 2) Patterns of the H-reflex and F-wave with increased stimulus intensity in patients with markedly increased muscle tone and tendon reflex were almost always type 4. Those with moderately increased signs in this parameter demonstrated type 2 or 3. Those with slightly increased signs in this parameter demonstrated type 1 or 2. Those with normal or decreased signs were type 1. These findings suggest that the characteristic appearances of the H-reflex and F-wave was influenced by grade of neurological signs.
- Published
- 2002
44. [The simple swallowing provocation test as a means of screening for swallowing disorders: a comparison with the water swallowing test]
- Author
-
S, Teramoto, T, Matsuse, H, Matsui, E, Ohga, E, Saitoh, T, Ishii, T, Tomita, T, Nagase, Y, Fukuchi, and Y, Ouchi
- Subjects
Male ,Methods ,Humans ,Female ,Deglutition Disorders ,Pneumonia, Aspiration ,Aged ,Deglutition - Abstract
The sensitivity and specificity of the simple swallowing provocation test (S-SPT) were evaluated in a group of patients who were being examined for aspiration pneumonia (ASP) (ASP group: 72.5 +/- 3.9 years old) and in a group of age-matched control subjects (CTRL group: 69.5 +/- 2.9 years old). The S-SPT was evaluated in terms of the swallowing response and latent time (LT) for swallowing after a bolus injection of 0.4 ml of distilled water at the suprapharynx. Responses to the S-SPT were classified as normal or abnormal, dependent on induction of the swallowing reflex within 3 seconds after bolus injection. The sensitivity and specificity of the S-SPT in detecting ASP were calculated. Of the 40 patients in the ASP group, 18 were given a diagnosis of ASP on the basis of clinical findings and laboratory examinations. The sensitivity and specificity of the S-SPT were 94.4% and 86.4%, respectively, compared to 77.8% and 68.1%, respectively, for the water swallowing test. Because the S-SPT can be performed without any need for special patient effort or cooperation, it should be effective in diagnosing ASP in a wide variety of patients, including those who are bedridden.
- Published
- 1999
45. Changes in impairment and disability from the third to the sixth month after stroke and its relationship evaluated by an artificial neural network
- Author
-
S, Sonoda, N, Chino, K, Domen, and E, Saitoh
- Subjects
Adult ,Aged, 80 and over ,Male ,Cerebrovascular Disorders ,Disability Evaluation ,Time Factors ,Activities of Daily Living ,Humans ,Female ,Neural Networks, Computer ,Middle Aged ,Aged - Abstract
Functional recovery in a rather late stage after stroke was examined in 70 stroke patients using the Stroke Impairment Assessment Set (SIAS) and the Functional Independence Measure (FIM). The SIAS and the FIM were administered at three and six months after the onset of stroke. Motor items and the abdominal manual muscle testing item improved in more than 30 percent of patients. The motor subscore of the FIM changed from 60.8 to 73.4, and the cognitive subscore changed from 28.4 to 30.4. The relationship between impairment and disability was evaluated using the neural network method with the software, Skiltran. The change of the FIM motor subscore from three months to six months was used as an output variable, and the change in the SIAS items and the FIM motor subscore were included as input variables. As a result of the connection weight obtained from this network, the change in the fifth motor item (one of the tone items, abdominal manual muscle testing) and the unaffected side grip as well as the FIM at three months had a strong connection to the change of the FIM. It is compatible with ordinary experience that function of both the affected and unaffected side influences the level of disability. Contribution of the impairment to the disability indicates the importance of taking into consideration the impairment for predicting prognosis and selecting adequate treatment when we carry out stroke rehabilitation. In conclusion, we described the relationship between the SIAS and the FIM using the neural network in stroke patients and proved the importance of the impairment to predict the outcome of disability.
- Published
- 1997
46. [Tc-99m labeled leukocyte scintigraphy and CT for the evaluation of patients with inflammatory bowel disease]
- Author
-
C, Miyazaki, K, Kubo, H, Aoyama, H, Endoh, Y, Odashima, and E, Saitoh
- Subjects
Adult ,Male ,Adolescent ,Organotechnetium Compounds ,Middle Aged ,Inflammatory Bowel Diseases ,Sensitivity and Specificity ,Technetium Tc 99m Exametazime ,Oximes ,Leukocytes ,Humans ,Female ,Child ,Radionuclide Imaging ,Tomography, X-Ray Computed - Abstract
Seventeen cases (11 patients) of inflammatory bowel disease (IBD) were studied to define the intensity and extent of disease by 99mTc-HMPAO-labeled leukocytes scintigraphy (TLLS), and 10 cases underwent CT examination to evaluate the bowel wall, lymph-nodes, and mesenteric surroundings. Serial TLLS were obtained up to 4 hours and CT was carried out within one week before or after TLLS. The sensitivities of early (1 hour) and delayed (4 hours) TLLS were 91% and 100%, respectively. The respective specificities were 100% and 33%. However, it appeared that mild IBD may yield false negative results in early TLLS while non-specific bowel activity and migration of white cells may cause false positive results in delayed imaging. By setting the diagnostic criteria for labeled leukocyte accumulation on visualization of the small bowel regardless of uptake or activity of the large bowel similar to or greater than lumbar bone marrow, the sensitivity and specificity of delayed TLLS changed to 91% and 83%, respectively. On CT examination, mesenteric lymph-node swelling, periintestinal blurring and dilatation of mesenteric vasa recta were observed in all five patients with active Crohn's disease, while wall thickening and enhancement were seen in four of them. None of the other three cases of inflammatory disease showed positive findings of dilatation of the mesenteric vasa recta, and they revealed relatively low uptake of labeled leukocytes in TLLS. A "scintigram score" was calculated by comparing uptake of tracer in five bowel segments with lumbar bone marrow activity, and a "CT score" was calculated by adding abnormalities of the intestine and mesenteric surroundings. The scintigram score correlated closely with CT score and clinical disease activity. Combined use of CT and TLLS for the evaluation of patients with IBD was an excellent means to obtain the findings of intensity and extent of disease of the bowel wall and mesenteric surroundings and provided useful information in determining the patient management.
- Published
- 1997
47. Clinical experience with a new hip-knee-ankle-foot orthotic system using a medial single hip joint for paraplegic standing and walking
- Author
-
E, Saitoh, T, Suzuki, S, Sonoda, J, Fujitani, Y, Tomita, and N, Chino
- Subjects
Adult ,Male ,Paraplegia ,Braces ,Oxygen Consumption ,Humans ,Walking ,Energy Metabolism ,Locomotion ,Spinal Cord Injuries - Abstract
The Walkabout is a new hip-knee-ankle-foot orthotic (HKAFO) system with a medial single hip joint (MSH-KAFO) invented by S. McKay in 1992. Compared with other HKAFO systems, the hip joint part is compact and removable, so it has distinguishable, real merits: ease in donning and doffing the device, compatibility with a wheelchair, and cosmesis. We clinically tested five patients, paraplegic because of spinal cord injury, using the MSH-KAFO system. All were males, aged 26-36 yr old. Their functional levels were L-1 (2 cases), T-10 (2 cases), and T-5 (1 case). All patients could stand stably without crutches and walk in parallel bars immediately the first time they wore the braces. After a few hours of crutch-walking exercises, all could walk independently with Lofstrand crutches. Their walking velocities ranged from 10 to 37.5 (mean, 19.9) m/min at the follow-up points (mean, 7.1 mo). With four cases, we measured oxygen uptake for predictions of energy consumption. At comfortable walking, predicted energy consumptions were from 1.31 to 3.89 (mean, 2.75) METs. Compared with the data in literature, these seemed to be at the same level with normal walking and lower than the KAFOs walking level. Our results suggest that MSH-KAFO is a very convenient standing and walking device for paraplegics and is compatible with wheelchair use.
- Published
- 1996
48. Production of human salivary type cysteine proteinase inhibitors (cystatins) by an Escherichia coli system and partial characterization of recombinant cystatin S and its mutant (117 arginine--tryptophan)
- Author
-
E, Saitoh and S, Isemura
- Subjects
DNA, Complementary ,Base Sequence ,Genetic Vectors ,Molecular Sequence Data ,Mutation ,Escherichia coli ,Tryptophan ,Humans ,Salivary Cystatins ,Amino Acid Sequence ,Arginine ,Cystatins ,Recombinant Proteins - Abstract
The cDNAs encoding the precursors of cystatin SN, cystatin S, and two mutants of cystatin S (-18R--W; 117R--W) were expressed in Escherichia coli JM109 with isopropyl-beta-D-thio-galactoside (IPTG) induction. Premature cystatin S with the original signal [-20MARPLCTLLLLMATLAGALA] was processed and a large amount of the mature form was produced. A mutation (-18R--W) in the signal reduced its accumulation in periplasmic space remarkably. The amount of cystatin SN accumulated in the periplasm was slightly smaller than that of cystatin S. The periplasmic fraction was prepared by cold osmotic-shock treatment and the expressed cystatins were detected using anti-cystatin S antibody. Recombinant cystatin S and its mutant (117R--W) were purified from the periplasmic fractions with an ion exchange column of DEAE-cellulose. The amino (N-) terminal 10 residues of recombinant cystatin S was sequenced to be SSSKEENRII-, which is exactly identical to that of the authentic mature cystatin S. Recombinant cystatin S and the mutant showed virtually the same inhibitory properties for ficin, papain and cathepsin B as the native cystatin S and its monophosphorylated form. The inhibitory activity of the both recombinant cystatins for cathepsin C was weaker than those of the native cystatin S and phosphorylated cystatin S.
- Published
- 1994
49. Molecular cloning and sequence analysis of cDNA coding for the precursor of the human salivary proline-rich peptide P-B
- Author
-
S, Isemura and E, Saitoh
- Subjects
DNA, Complementary ,Genome ,Base Sequence ,Proline ,Molecular Sequence Data ,Submandibular Gland ,Mice ,Genetic Code ,Sequence Homology, Nucleic Acid ,Animals ,Humans ,Proline-Rich Protein Domains ,Amino Acid Sequence ,Cloning, Molecular ,Genome, Fungal ,Protein Precursors ,Salivary Proteins and Peptides ,Peptides - Abstract
cDNA coding for the human salivary proline-rich peptide P-B was amplified by polymerase chain reaction using human submaxillary gland cDNA as the template and d(deoxy)T25 as the primer for both strands. The amplified cDNA of 0.8 kbp encodes a hydrophobic signal sequence of 22 amino acid residues and the complete sequence of P-B (57 amino acids). The determined nucleotide sequence of P-B cDNA indicates that P-B is a mature full-size protein and not the enzymic degradation product of a larger protein. The gene coding for P-B is not a member of the proline-rich protein gene family characterized previously.
- Published
- 1994
50. Influence of fibril length upon ePTFE graft healing and host modification of the implant
- Author
-
Kunihiko Hirabayashi, Hiroshi Ijima, M. Kodama, Motokazu Hori, T. Takenawa, and E. Saitoh
- Subjects
Male ,medicine.medical_specialty ,Materials science ,Biocompatibility ,Graft healing ,Biomedical Engineering ,Biocompatible Materials ,Expanded polytetrafluoroethylene ,Fibril ,Muscle, Smooth, Vascular ,Biomaterials ,Hydroxyproline ,chemistry.chemical_compound ,medicine ,Animals ,Aorta, Abdominal ,Rats, Wistar ,Polytetrafluoroethylene ,Wound Healing ,Significant difference ,Surgery ,Blood Vessel Prosthesis ,Rats ,chemistry ,Microscopy, Electron, Scanning ,Implant ,Vascular graft ,Biomedical engineering - Abstract
Influence of fibril length (porosity) upon synthetic vascular graft healing has not been investigated in detail. The purpose of this study was to determine the dependence of neoendothelial healing, cellular response, and biocompatibility on the fibril length of expanded polytetrafluoroethylene (ePTFE) grafts with an internal diameter of 1.5 mm. ePTFE grafts of different fibril length, 20, 40, 60, and 90 microns, were implanted into the abdominal aorta of rats (n = 5 for each group). After 5 weeks, the implants were harvested and examined for neointimal and pseudointimal coverage by light microscopy and SEM. The hydroxyproline content of the implants was measured, and the distribution of collagen types was examined. The neointimal and pseudointimal coverage was related to the fibril length, and the neoendothelial healing was better on 60-microns and 90-microns grafts than on 20-microns and 40-microns grafts. The amount of hydroxyproline was also related to the fibril length, however, no significant difference could be observed between 60-microns and 90-microns grafts. Collagen types I and III were almost identically located in the middle portion of the implants. Our results demonstrate that the fibril length of ePTFE grafts affected neoendothelial healing and its affinity to collagen.
- Published
- 1992
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