78 results on '"Tetsuya Tsukada"'
Search Results
2. Comparison of hemodynamic stress in healthy vessels after parent artery occlusion and flow diverter stent treatment for internal carotid artery aneurysm
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Haruo Isoda, Takashi Izumi, Tetsuya Tsukada, Takashi Mizuno, A Elisabeth Kropp, Masahiro Nishihori, and Toshihiko Wakabayashi
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Carotid Artery Diseases ,medicine.medical_specialty ,Flow diverter stent ,business.industry ,Hemodynamics ,Intracranial Aneurysm ,General Medicine ,Internal carotid artery aneurysm ,medicine.disease ,Aneurysm ,medicine.artery ,Internal medicine ,cardiovascular system ,Cardiology ,Humans ,Medicine ,Stents ,Posterior communicating artery ,Internal carotid artery ,business ,Hemodynamic stress ,Carotid Artery, Internal ,Parent artery occlusion ,Flow diverter - Abstract
OBJECTIVE De novo aneurysms generally develop in healthy vessels after parent artery occlusion for large internal carotid artery (ICA) aneurysm, possibly owing to increased hemodynamic stress in the remaining vessels. In recent years, there has been a shift toward flow diverter stent treatment. However, there is a lack of direct evidence and data that prove this change in hemodynamic stress in healthy vessels after parent artery occlusion and flow diverter stent treatment. The authors compared hemodynamic stress in healthy-side vessels before and after parent artery occlusion and flow diverter treatments. METHODS The authors included patients who underwent 3D cine phase-contrast MRI before and after large ICA aneurysm treatment. Spatially and temporally averaged volume flow rates and spatially averaged systolic wall shear stress (WSS) in healthy-side ICA distal to the posterior communicating artery (C1 segment according to Fisher’s classification) were measured before and after parent artery occlusion and flow diverter treatments. RESULTS Seventeen patients were included (5 patients in the parent artery occlusion group and 12 in the flow diverter group). At 1–2 months after treatment, median volume flow rate in healthy-side ICA increased from 5.36 ml/sec to 6.28 ml/sec (total increase 117%, p = 0.04) in the parent artery occlusion group and from 4.65 ml/sec to 4.93 ml/sec (total increase 106%, p = 0.02) in the flow diverter group. In the parent artery occlusion group, median WSS in the C1 segment of the healthy-side ICA increased from 3.91 Pa to 5.61 Pa (total increase 143%, p = 0.08); however, no significant increase was observed in the flow diverter group (4.29 Pa to 4.57 Pa [total increase 107%, p = 0.21]). CONCLUSIONS Postoperatively, volume flow rate and WSS in the C1 segment of the healthy-side ICA significantly increased in the parent artery occlusion group. Therefore, the parent artery occlusion group was more prone to de novo aneurysm than the flow diverter group.
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- 2022
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3. Contrast-Enhanced Magnetic Resonance Imaging Suggested a Possibility of Transvenous Embolization in the Superior Petrosal Sinus Dural Arteriovenous Fistula: A Case Report
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Kenji Uda, Ryuta Saito, Masahiro Nishihori, Yutaka Kato, Yoshio Araki, Tetsuya Tsukada, Takashi Izumi, and Kinya Yokoyama
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medicine.medical_specialty ,business.industry ,Transvenous embolization ,Superior petrosal sinus ,Medicine ,Arteriovenous fistula ,Neurology (clinical) ,Radiology ,Cardiology and Cardiovascular Medicine ,business ,medicine.disease ,Contrast-enhanced Magnetic Resonance Imaging - Published
- 2022
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4. Management of Asymptomatic Vertebral Artery Injury Caused by a Cervical Pedicle Screw Malposition: Two Case Reports
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Mizuka Ikezawa, Shunsaku Goto, Masahiro Nishihori, Takafumi Otsuka, Naoki Kato, Mizuki Nakano, Takashi Izumi, Kinya Yokoyama, Yoshio Araki, Kenji Uda, Tetsuya Tsukada, and Ryuta Saito
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medicine.medical_specialty ,Vertebral artery injury ,business.industry ,Case Report ,spinal diseases ,thromboembolism ,Asymptomatic ,stroke ,Surgery ,consensus ,medicine ,medicine.symptom ,Pedicle screw ,business - Abstract
Iatrogenic vertebral artery (VA) injury in cervical fusion is an extremely rare complication but can lead to serious sequelae. We present two successful cases of internal trapping for preventing delayed-onset ischemic stroke after iatrogenic VA stenosis caused by a cervical pedicle screw. A 34-year-old female underwent posterior cervical fusion for C4/C5 dislocation fracture. No neurological deficits were observed after the operation. However, the postoperative images revealed that the left C5 pedicle screw perforated the transverse foramen, and the left VA was suspected to be occluded at the screw insertion site. Before revision surgery, we tried to embolize the injured VA with coils. A microcatheter could be navigated from the ipsilateral VA to the distal of the screw, and internal trapping was performed with coils. Another case is that of a 50-year-old male with cervical spondylosis, who underwent posterior decompression and cervical fusion. The neurological symptoms did not deteriorate after the operation. However, the postoperative computed tomography images revealed the perforation of the right C3 transverse foramen by the pedicle screw. In right vertebral angiography, about 70% stenosis was observed at the screw insertion site. Although revision surgery was not planned due to good stability, we embolized the right VA after balloon occlusion test, to prevent the delayed-onset thromboembolic complications. Both the patients recovered without any neurological deficits. Iatrogenic VA injuries, even if asymptomatic immediately after surgery, can lead to serious sequelae in case of delayed-onset ischemic stroke. Therefore, careful attention should be paid when the screw perforates the transverse foramen.
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- 2021
5. The preoperative focal cerebral blood flow status may be associated with slow flow in the bypass graft after combined surgery for moyamoya disease
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Yoshio Araki, Kinya Yokoyama, Kenji Uda, Fumiaki Kanamori, Takashi Mamiya, Kai Takayanagi, Kazuki Ishii, Kazunori Shintai, Masahiro Nishihori, Tetsuya Tsukada, Kazuhito Takeuchi, Kuniaki Tanahashi, Yuichi Nagata, Yusuke Nishimura, Takafumi Tanei, Yoshitaka Nagashima, Shinsuke Muraoka, Takashi Izumi, Yukio Seki, and Ryuta Saito
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Surgery ,Neurology (clinical) - Abstract
Background: The aim of this study was to investigate the association between early postoperative slow flow in bypass grafts and preoperative focal cerebral blood flow (CBF) in patients who underwent combined surgery for moyamoya disease (MMD). Methods: The subjects were 18 patients (22 surgeries) who underwent single photon emission computed tomography (SPECT) before surgery. The CBF value of the middle cerebral artery territory was extracted from the SPECT data, and the value relative to the ipsilateral cerebellar CBF (relative CBF, or RCBF) was calculated. The association between RCBF and early postoperative slow flow in the bypass graft was investigated. In addition, the correlation between the revascularization effect and preoperative RCBF was analyzed. Results: In four of 22 surgeries (18.2%), slow flow in the bypass graft was identified in the early postoperative period. Preoperative RCBF in the slow flow and patent groups was 0.86 ± 0.15 and 0.87 ± 0.15, respectively, with no significant difference (P = 0.72). The signal intensity of four slow-flowed bypasses was improved in all cases on magnetic resonance angiography images captured during the chronic phase (mean of 3.3 months postoperatively). The revascularization scores were 2 ± 0.82 and 2.1 ± 0.68 in the slow flow and patent groups, respectively, and did not differ significantly (P = 0.78). A significant correlation was not observed between preoperative RCBF and the revascularization effect. Conclusion: No significant association was observed between preoperative RCBF and early postoperative slow flow in bypass grafts in patients with MMD undergoing combined surgery. Given the high rate of improved depiction of slow-flowed bypass in the chronic postoperative phase, the conceptual significance of an opportune surgical intervention is to maintain CBF by supporting the patient’s own intracranial-extracranial conversion function.
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- 2022
6. Evaluation of the Straightening Phenomenon of Various Types of Coils
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Masahiro Nishihori, Toshihiko Wakabayashi, Tetsuya Tsukada, Kenji Uda, Kinya Yokoyama, Mamoru Ishida, Takashi Izumi, and Yoshio Araki
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straightening phenomenon ,business.industry ,Experimental model ,Economic shortage ,Intracranial Aneurysm ,embolization ,Equipment Design ,Embolization, Therapeutic ,030218 nuclear medicine & medical imaging ,03 medical and health sciences ,0302 clinical medicine ,Nuclear magnetic resonance ,Late phase ,Electromagnetic coil ,aneurysm ,Medicine ,coil ,Humans ,Surgery ,Original Article ,Neurology (clinical) ,business ,030217 neurology & neurosurgery ,Coil embolization - Abstract
The straightening phenomenon is known as a cause of catheter kickback in the late phase of coil embolization. The mechanism is supposed to be the relative shortage of the stretch resistance (SR) line, and it occurs when a coil is folded too small. Among many SR coils available, there should be a coil-specific tendency to cause this phenomenon. Here, we conducted an in-vitro experiment to know which coil is the most resistant to the straightening phenomenon. We developed an experimental model to reproduce the straightening phenomenon. Five different coils (Axium Prime, ED Coil, Hypersoft, SMART Coil, and Target 360 nano) of the same size (3 mm × 6 cm) were investigated for five times each. Resistance to the straightening phenomenon, which is represented by the insertion length at the onset of the phenomenon, was compared among coil types. The straightening phenomenon was successfully observed in all insertions. Insertion lengths were significantly different among coil types (p = 0.013). The insertion length of ED was the longest (mean ± SD, 27.0 ± 8.3 mm), which means the most resistant to the phenomenon. Axium was second (21.6 ± 7.0 mm), followed by Target (15.8 ± 6.9 mm), Hypersoft (13.8 ± 5.8 mm), and SMART (12.4 ± 4.7 mm). Difference between ED and Hypersoft (p = 0.037) and difference between ED and Smart (p = 0.018) were significant. ED coil was the one with the most resistance to the straightening phenomenon. Selecting the optimal coil is the key to avoid the phenomenon.
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- 2021
7. Levodopa-responsive Parkinsonism Caused by Recurrence of Large Basilar-tip Aneurysm after Stent-assisted Coil Embolization: A Case Report
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Kenji Uda, Kinya Yokoyama, Takashi Izumi, Masahiro Nishihori, Yoshio Araki, Toshihiko Wakabayashi, and Tetsuya Tsukada
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medicine.medical_specialty ,Levodopa ,business.industry ,endovascular procedure ,Parkinsonism ,medicine.medical_treatment ,Stent ,Case Report ,medicine.disease ,intracranial aneurysm ,cardiovascular system ,Medicine ,basilar artery ,Radiology ,Basilar tip aneurysm ,cardiovascular diseases ,levodopa ,business ,parkinsonism ,Coil embolization ,medicine.drug - Abstract
Aneurysms of the large basilar artery (BA) occasionally cause cranial nerve palsy and motor disorder through mass effect. Since 1967, five cases of cerebral aneurysm leading to parkinsonism have been reported. Herein, we describe a rare case of progressive parkinsonism caused by the recurrence of a large aneurysm of the basilar tip after stent-assisted coil embolization. A 66-year-old man visited our hospital with an asymptomatic large aneurysm (maximum diameter, 21 mm) of the BA tip. Magnetic resonance imaging (MRI) revealed no perianeurysmal edema. Coil embolization with a Y-configuration stent with cross-placement was performed. Although thrombus formation occurred and the perforator infarction was complicated, complete occlusion was achieved. Three months later, the patient developed progressive and severe parkinsonism. MRI revealed mild enlargement of the aneurysm and perianeurysmal mesencephalic edema with minor neck recurrence. A trial administration of levodopa and additional stent-assisted coil embolization were performed. Levodopa dramatically improved parkinsonism; thus, the patient’s symptoms were controlled by a continuous levodopa regimen. In a large BA-tip aneurysm patient, moderate regrowth and minor neck recurrence occurred after initial treatment, and chronic compression of the midbrain caused secondary parkinsonism. In such cases, it is important to consider levodopa administration and therapeutic strategies to prevent recurrence or regrowth.
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- 2021
8. A Basilar Membrane Model Using Simulink for Hearing-Aid Systems.
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Tetsuya Tsukada and Yoshifumi Sekine
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- 2004
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9. Coexistence of a Dural Arteriovenous Fistula and Pial Arteriovenous Malformation Sharing a Common Drainer
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Tetsuya Tsukada, Masahiro Nishihori, Kinya Yokoyama, Yoshio Araki, Kazunori Shintai, Sho Okamoto, Fumiaki Kanamori, Takashi Izumi, and Kenji Uda
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congenital, hereditary, and neonatal diseases and abnormalities ,medicine.medical_specialty ,business.industry ,arteriovenous malformation ,Arteriovenous fistula ,Case Report ,Arteriovenous malformation ,medicine.disease ,Surgery ,nervous system ,common drainer ,cardiovascular system ,medicine ,cardiovascular diseases ,business ,dural arteriovenous fistula ,circulatory and respiratory physiology - Abstract
In cases of a dural arteriovenous fistula (AVF) with a pial arterial supply, postoperative hemorrhagic complications occur frequently. Six cases in which patients were diagnosed with a coexisting dural AVF and pial arteriovenous malformation (AVM) sharing a common drainer are presented. These cases were initially thought to be dural AVFs with pial arterial supplies, but careful examination of preoperative images showed that a pial AVM coexisted near the dural AVF, and that both shared a common drainer. The coexistence of a pial AVM is difficult to notice during surgery; for this reason, determining the presence of a pial AVM on preoperative imaging is essential to safely treat a dural AVF with a pial arterial supply. The details of each case, specifically, the diagnostic evidence for this condition (coexisting dural AVF and pial AVM sharing a common drainer), as well as imaging findings that should be noted, are presented.
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- 2021
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10. Outcomes and Issues of ‘Drip and Go’ as an Inter-Hospital Cooperation System in Mechanical Thrombectomy for Acute Ischemic Stroke
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Tetsuya Tsukada, Takashi Izumi, Yoshio Araki, Toshihiko Wakabayashi, Kinya Yokoyama, Kenji Uda, and Masahiro Nishihori
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Mechanical thrombectomy ,medicine.medical_specialty ,business.industry ,Emergency medicine ,medicine ,Neurology (clinical) ,Cardiology and Cardiovascular Medicine ,business ,Acute ischemic stroke - Published
- 2021
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11. Short-segment Internal Trapping for Symptomatic Thrombosed Large Fusiform Vertebral Artery Aneurysms (Bird’s Nest Trapping): A Technical Note
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Tetsuya Tsukada, Kinya Yokoyama, Kenji Uda, Takashi Izumi, Asuka Elisabeth Kropp, Masahiro Nishihori, Yoshio Araki, and Toshihiko Wakabayashi
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endovascular treatment ,Male ,medicine.medical_specialty ,Medullary cavity ,Vertebral artery ,Infarction ,Balloon ,030218 nuclear medicine & medical imaging ,Birds ,03 medical and health sciences ,0302 clinical medicine ,Aneurysm ,medicine.artery ,Technical Note ,medicine ,Animals ,Humans ,Vertebral Artery ,business.industry ,thrombosed aneurysm ,Intracranial Aneurysm ,Thrombosis ,Technical note ,Enbucrilate ,medicine.disease ,NBCA ,Embolization, Therapeutic ,internal trapping ,medicine.anatomical_structure ,Rotational angiography ,Surgery ,vertebral artery aneurysm ,Neurology (clinical) ,Radiology ,business ,030217 neurology & neurosurgery ,Artery - Abstract
Internal trapping with coils is an established treatment of symptomatic large non-branching thrombosed fusiform vertebral artery aneurysms (VAA). However, when perforators arise near the aneurysm neck, parent artery occlusion has a high risk of causing medullary infarction. As an alternative treatment, we performed short-segment internal trapping of the artery using n-butyl-2-cyanoacrylate (NBCA) and coils (bird's nest trapping). Before treatment, perianeurysmal perforators are carefully detected using high-resolution three-dimensional rotational angiography (3DRA). Double microcatheters are advanced to the distal portion of the aneurysm through a balloon guiding catheter where coils are deployed without tight packing. Then, NBCA is injected into the coil mass, taking care to preserve perforators and significant branches. The same maneuver is repeated in the proximal portion of the aneurysm. Coil placement is avoided within the middle of the aneurysm; however, if necessary, only a small number of coils are placed to prevent worsening of mass effect. Two quinquagenarian males presented with a large thrombosed fusiform VAA that caused symptoms due to mass effect. In each case, perforators arose from the parent artery and short-segment internal trapping with NBCA and coils was performed. Symptoms improved after treatment and follow-up imaging confirmed aneurysm shrinkage with no long-time recurrence. In symptomatic large fusiform VAAs where the distance from the lesion to important perforators is extremely short, internal trapping using a combination of NBCA and coils can be more useful than conventional internal trapping.
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- 2021
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12. Triggering of Carotid Sinus Reflex during Deployment of the Flow-diverter Device
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Kenji Uda, Kinya Yokoyama, Takashi Izumi, Ryuta Saito, Shunsaku Goto, Masahiro Nishihori, Tetsuya Tsukada, and Yoshio Araki
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Bradycardia ,medicine.medical_specialty ,Sedation ,medicine.medical_treatment ,Vital signs ,complication ,chemical and pharmacologic phenomena ,cardiac arrest ,bradycardia ,Aneurysm ,medicine.artery ,Internal medicine ,Reflex ,parasitic diseases ,medicine ,Humans ,Local anesthesia ,Embolization ,Aged ,Retrospective Studies ,business.industry ,flow diverter ,Intracranial Aneurysm ,medicine.disease ,Embolization, Therapeutic ,Carotid Sinus ,Treatment Outcome ,Blood pressure ,aneurysm ,Cardiology ,Original Article ,Surgery ,Neurology (clinical) ,Internal carotid artery ,medicine.symptom ,business ,Carotid Artery, Internal - Abstract
The carotid sinus reflex (CSR) is a rare complication of the Pipeline Embolization Device (PED) deployment. No study has assessed the potential risk factors in a case series. The purpose of this study was to examine CSR triggering during PED deployment. Thirty-seven consecutive patients who underwent PED deployment were included. All procedures were performed under local anesthesia with mild sedation. We retrospectively analyzed patient characteristics, PED deployment time, and vital signs during the procedure. The vital signs included the pulse rate (PR) and systolic blood pressure (SBP) obtained at three timepoints (pre-deployment, during deployment, post-deployment). We examined the triggering of the CSR during PED deployment by comparing the vital signs at the three timepoints. Moreover, risk factors for CSR were analyzed with univariate analysis. The patients' average age was 66.3 years. The average size of the aneurysm was 18.0 mm. Six patients (16.2%) showed a decline in the SBP or PR defined as CSR. One patient had a transient cardiac arrest and two had severe transient bradycardia. Deployment into the ophthalmic segment of the internal carotid artery (C2 segment) aneurysm (p = 0.022), prolonged PED deployment time more than 14.5 minutes (p = 0.005), and an acute angle of the anterior genu less than 51.5 degrees (p = 0.005) were risk factors in triggering CSR. CSR may be triggered during PED deployment under local anesthesia with mild sedation. Deployment to the C2 segment aneurysm, prolonged PED deployment time, and an acute angle of the anterior genu were associated with CSR triggering.
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- 2021
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13. Structure and reaction mechanism of binary Ni–Al oxides as materials for lithium-ion battery anodes
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Tetsuya Tsukada, Patrick K. Dedetemo, Noriyuki Sonoyama, Kaori Niki, Akihiro Koide, Yoshitaka Ogasawara, and Mina Eguchi
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Materials science ,Analytical chemistry ,Layered double hydroxides ,Oxide ,chemistry.chemical_element ,Electrolyte ,engineering.material ,Electrochemistry ,Lithium-ion battery ,Ion ,Inorganic Chemistry ,chemistry.chemical_compound ,chemistry ,engineering ,Lithium ,Solid solution - Abstract
A nanometer sized solid solution of NiO and Al2O3 was synthesized by calcination of Ni–Al layered double hydroxides (LDHs). The crystal structure of the obtained compound was determined by XRD and XAFS analyses: Ni2+ and Al3+ ions are located at the metal ion site of the rock salt structure and a certain amount of cation vacancies are also introduced for charge compensation. The electrochemical properties of the Ni–Al binary metal oxide as an anode material for lithium ion batteries were examined by the constant current charge–discharge test. Ni–Al oxide showed higher charging capacity in comparison with pristine NiO. In particular, the capacity in the lower voltage region (below 1.5 V), the limited capacity in this region is the weak point of the conversion anode, was improved to 540 mA h g−1 that is about twice that of pristine NiO. This improvement in the capacity in the lower voltage region is concluded to be due to the redox activity of Al3+ ions during the charge–discharge on the basis of the results of electrochemical measurements and ex situ XAFS measurements at the Ni and Al edge. The reaction mechanism of this compound is investigated using ex situ XRD and XAFS methods. For the charge (reduction) in the higher voltage region (OCV–1.0 V), lithium ion intercalation into the cation vacancy sites and/or lithium ion adsorption on the surface of particles are proceeding. For the charge in the lower voltage region (1.0–0.03 V), conversion reaction occurs by the reduction of Ni2+ and Al3+ ions to metal particles with surface electrolyte interface (SEI) layer formation. For the discharge in the lower voltage region (0.03–1.5 V), only Al metal particles are oxidized to Al3+ ions and some intermediate complexes are formed. For the discharge in the higher voltage region (1.5–3.0 V), the lattice of the Ni–Al binary oxide solid solution is reconstructed with the oxidation of Ni to Ni2+.
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- 2021
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14. Streak Metal Artifact Reduction Technique in Cone Beam Computed Tomography Images after Endovascular Neurosurgery
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Takeshi Uemura, Yoshio Araki, Mizuki Nakano, Ryuta Saito, Masahiro Nishihori, Takashi Sakai, Kinya Yokoyama, Kenji Uda, Takafumi Otsuka, Naoki Kato, Tetsuya Tsukada, Fumiaki Kanamori, and Takashi Izumi
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endovascular neurosurgery ,Cone beam computed tomography ,non-contrast cone beam computed tomography ,medicine.medical_treatment ,Neurosurgery ,Streak ,Arteriovenous fistula ,Metal Artifact ,Aneurysm ,medicine ,Humans ,Endovascular neurosurgery ,dural arteriovenous fistula ,Reduction (orthopedic surgery) ,business.industry ,Cistern ,Cone-Beam Computed Tomography ,medicine.disease ,Metals ,aneurysm ,Original Article ,Surgery ,Neurology (clinical) ,Artifacts ,streak metal artifact reduction technique ,Nuclear medicine ,business ,Algorithms - Abstract
Cone beam computed tomography (CBCT) images are degraded by artifacts due to endovascular implants. We evaluated the use of streak metal artifact reduction technique (SMART) in non-contrast CBCT images after endovascular neurosurgery obtained from 148 patients (125 with aneurysm and 23 with dural arteriovenous fistula [dAVF]). Three neurosurgeons evaluated the cistern and brain surface visibility in CBCT images with and without SMART correction based on a 4-point scale (1, excellent; 2, good; 3, limited; and 4, insufficient). Significant improvement in visibility was achieved when the median scores improved from 4 or 3 to 2 or 1 or from 2 to 1. Metal artifact reduction in adjacent slices without metal and new artifacts after SMART correction was also examined. A significant improvement was achieved regarding the visibility of the cistern in 90 (60.8%) images and of the brain surface in 108 (73.0%) images. Metal size (cistern: odds ratio [OR], 0.91 per 1 mm increase; 95% confidence interval [CI], 0.83–0.99), irregular metal shape (cistern: OR, 0.18; 95% CI, 0.05–0.60 and brain surface: OR, 0.15; 95% CI, 0.05–0.45), and infratentorial lesions (cistern: OR, 0.37; 95% CI, 0.14–0.96 and brain surface: OR, 0.30; 95% CI, 0.11–0.80) were negatively correlated with improved visibility. Metal artifact reduction in adjacent slices without metal was obtained in 25.6% and 34.8% of images with aneurysm and dAVF, respectively. New artifacts after SMART correction were found in 4.8% and 13.0% of images with aneurysm and dAVF, respectively. SMART is especially effective for supratentorial small aneurysms.
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- 2021
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15. Efficacy of Respiratory Control under Local Anesthesia during Endovascular Therapy in the Tortuous Vertebral Artery with the Use of Respiratory Dislocation of the Aortic Arch
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Tetsuya Tsukada, Shunsaku Goto, Kinya Yokoyama, Yoshio Araki, Takashi Izumi, Kenji Uda, Masahiro Nishihori, and Mizuka Ikezawa
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Aortic arch ,medicine.medical_specialty ,business.industry ,Vertebral artery ,Endovascular therapy ,Surgery ,medicine.artery ,medicine ,Guiding catheter ,Local anesthesia ,Respiratory control ,Neurology (clinical) ,Respiratory system ,Cardiology and Cardiovascular Medicine ,business - Published
- 2021
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16. Differences in gaze behaviors between trainees and experts during endovascular therapy for cerebral aneurysms: a preliminary study using a cerebral aneurysm model.
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Takafumi Otsuka, Takashi Izumi, Masaya Yamamoto, Yusuke Seshita, Takeshi Kohama, Masahiro Nishihori, Tetsuya Tsukada, and Ryuta Saito
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ENDOVASCULAR surgery ,MEDICAL education ,EYE movements ,EYE tracking ,DIAGNOSTIC imaging - Abstract
In the neuroendovascular field, the training of operators has become an important issue. Recently, eye-tracking technology has been introduced into various fields of medical education. This study aimed to apply eye-tracking technology to the training of neuroendovascular therapy. Six neurosurgeons, including three neuroendovascular specialists and three trainees, at our institution and related facilities participated in the study. Eye movement was recorded by the eye-tracking device during the microcatheter navigation and coil placement into the silastic aneurysm model under biplane X-ray fluoroscopy. Eye-tracking analysis during neuroendovascular therapy was feasible in all six subjects. In microcatheter navigation, specialists tended to more frequently switch their attention between frontal and lateral images than trainees. In coil embolization, the overall gaze frequency tended to increase, and the average fixation duration tended to decrease as the number of experienced cases increased. Inexperienced operators tend to fix their gaze when they are operators than when they are assistants. More experienced operators tended to look at the microcatheter longer in the coil insertion task. The eye-tracking analysis may be useful for operator training in neuroendovascular therapy. Experts may have moved their eyes more frequently than trainees to gaze at the right place. In the future, it will be necessary to collect gaze data for more operators in various tasks. [ABSTRACT FROM AUTHOR]
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- 2023
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17. Evaluation of the differences in pressure applied to the vessel wall by different types of balloon remodeling microcatheters in an experimental model
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Mizuka Ikezawa, Tetsuya Tsukada, Kinya Yokoyama, Mizuki Nakano, Yosuke Tamari, Yoshio Araki, Masahiro Nishihori, Kenji Uda, Takashi Izumi, Naoki Kato, Asuka Elisabeth Kropp, Shunsaku Goto, Takafumi Otsuka, and Ryuta Saito
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business.industry ,Experimental model ,Significant difference ,Balloon catheter ,Original Articles ,Models, Theoretical ,Balloon ,Compliance (physiology) ,Medicine ,Humans ,Tube (fluid conveyance) ,business ,Balloon Embolization ,Hole size ,Biomedical engineering - Abstract
Background We examined compliance differences among balloon remodeling microcatheters, which have not been established previously. Methods Straight and 120° angulated vascular models were created in a 3 mm diameter tube with 3 mm hole (vascular model A), a tube with a 4 mm hole (vascular model B), and a 4 mm diameter tube (vascular model C). We compared the pressure exerted when each balloon was herniated 1 or 2 mm between three compliant balloons (SHOURYU SR, TransForm C, and Scepter C) and four super-compliant balloons (HyperForm, SHOURYU HR, TransForm SC, and Scepter XC). Results In vascular model A, there was a significant difference in the pressure exerted by compliant balloons and super-compliant balloons in both the straight and angulated models. In the straight model (1 and 2 mm), the lowest pressure was exerted by HyperForm (super-compliant balloons group) and SHOURYU SR (compliant balloons group). The lowest pressure was exerted in the angulated model by HyperForm (super-compliant balloons group) and Scepter C (compliant balloons group). The Scepter balloon exerted higher pressure in the straight model than other balloon remodeling microcatheters but less in the angulated model. In vascular model B, the pressure decreased in all balloons compared with model A. In vascular model C, the pressure increased in all balloons compared with model A. Conclusions Pressure differed across balloon remodeling microcatheters. In addition, vessel shape and diameter, and hole size, affected the results. Our findings can help select balloon remodeling microcatheters.
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- 2021
18. Abnormal foreshortening of a Flow Re-Direction Endoluminal Device caused by in-stent thrombosis immediately after deployment.
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Takafumi Otsuka, Takashi Izumi, Masahiro Nishihori, Tetsuya Tsukada, Shunsaku Goto, Mizuka Ikezawa, Naoki Kato, Mizuki Nakano, Kenji Uda, Kinya Yokoyama, Yoshio Araki, and Ryuta Saito
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INTRACRANIAL aneurysms ,THROMBOEMBOLISM ,THROMBOSIS ,SURGICAL stents ,VASCULAR catheters - Abstract
Thromboembolic complications are a concern in the treatment of cerebral aneurysms using a flow diverter. In this study, we report a case of abnormal foreshortening of a Flow Re-Direction Endoluminal Device (FRED) caused by in-stent thrombosis immediately after its deployment. A 72-year-old woman had a large cavernous carotid aneurysm, which caused ptosis and diplopia. FRED deployment was planned, and dual antiplatelet therapy was initiated 2 weeks before the procedure. Under systemic heparinization, FRED was deployed with local compaction over the aneurysm orifice. Cone-beam computed tomography subsequently revealed slightly poor wall apposition at the proximal side. While the balloon catheter was prepared for angioplasty, the stent became abnormally foreshortened, the proximal side slipped into the aneurysm, and the internal carotid artery became occluded. FRED was removed using a snare wire, and recanalization was obtained. The lumen of the removed FRED was filled with thrombus. The antiplatelet therapy was changed to triple regimen, and a Pipeline Flex embolization device was placed 1 month later. At that time, no thromboembolic complications were noted. It was considered that thrombotic occlusion was followed by foreshortening of FRED on the distal side because of antegrade blood flow. Multiple factors, such as increased mesh density by locally compacted stent deployment, slightly poor wall apposition, clopidogrel resistance, and the dual-layer structure of FRED, may have been involved in thrombus formation. [ABSTRACT FROM AUTHOR]
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- 2022
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19. Analysis of relationship between superior hypophyseal artery visualization and preservation and postoperative visual field deficit in paraclinoid aneurysm
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Masato, Otawa, Takashi, Izumi, Masahiro, Nishihori, Tetsuya, Tsukada, Ryosuke, Oshima, Tomomi, Kawaguchi, Shunsaku, Goto, Mizuka, Ikezawa, Asuka Elisabeth, Kropp, Yoshio, Araki, Kenji, Uda, and Toshihiko, Wakabayashi
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Adult ,Carotid Artery Diseases ,Male ,Original Paper ,genetic structures ,Vision Disorders ,superior hypophyseal artery ,Angiography, Digital Subtraction ,Arteries ,Middle Aged ,coil embolization ,Aneurysm ,Embolization, Therapeutic ,Imaging, Three-Dimensional ,Pituitary Gland ,paraclinoid aneurysm ,Humans ,Female ,Visual Fields ,visual field deficit ,Carotid Artery, Internal ,Aged ,Retrospective Studies - Abstract
Direct surgery for paraclinoid aneurysms can result in visual field deficit owing to compromised blood flow to the superior hypophyseal artery (SHA). However, it is rarely visualized in angiography, and discussions regarding its preservation in the field of neuro-endovascular treatment are limited. Biplane angiographic suite with high spatial resolution has been used at our institution since 2014. Since then, there were a few cases where SHAs could be visualized via digital subtraction angiography. We retrospectively analyzed the relationship between the presences and abscence of SHAs in paraclinoid aneurysms and post-procedural visual field deficit. Sixty-three paraclinoid aneuryms treated by neuro-endovascular procedure in 2014–2018 at our neurosurgery department were analyzed. Pre- and post-procedural multiplanar reconstruction imagings of three-dimensional rotation angiography were analyzed to retrospectively investigate the SHAs. SHAs were visualized in 26 patients (41%) and the median number of pre-procedurally visualized SHAs was 0 (interquartile range 0–1). Their origins were the aneurysmal necks in 11 patients (42%). In two of the 11 cases, they were noticed before coil embolization and were able to be preserved after the procedure. In the remaining nine cases, they were not pre-procedurally detected, and coiling was normally conducted. Visual field deficit occurred in one of these nine cases, but symptoms were transient, and the patient fully recovered. Because SHAs could be visualized in >40% cases and no visual field defects occurred in cases that SHAs could be identified and preserved preoperatively, we recommend their preservation during coil embolization for paraclinoid aneurysms.
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- 2021
20. Light chain proximal tubulopathy diagnosed solely by electron microscopy of a renal biopsy specimen in a patient with monoclonal gammopathy of undetermined significance
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Tomohiro Murata, Tetsuya Tsukada, Yuka Sugimoto, Hirofumi Machida, Keiki Nagaharu, and Mika Fujimoto
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medicine.medical_specialty ,Pathology ,Biopsy ,Immunoglobulin light chain ,Monoclonal Gammopathy of Undetermined Significance ,law.invention ,Kidney Tubules, Proximal ,law ,Internal medicine ,medicine ,Humans ,Aged, 80 and over ,Hematology ,medicine.diagnostic_test ,business.industry ,medicine.disease ,Proximal Tubulopathy ,Female ,Immunoglobulin Light Chains ,Kidney Diseases ,Renal biopsy ,Symptom Assessment ,Electron microscope ,business ,Biomarkers ,Monoclonal gammopathy of undetermined significance - Published
- 2021
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21. Development and clinical evaluation of a contactless operating interface for three-dimensional image-guided navigation for endovascular neurosurgery
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Tetsuya Tsukada, Masaki Sato, Yoshitaka Nagano, Takashi Izumi, Asuka Elisabeth Kropp, Masahiro Nishihori, and Toshihiko Wakabayashi
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Operating Rooms ,Workstation ,Computer science ,Interface (computing) ,Contactless interface ,02 engineering and technology ,Neurosurgical Procedures ,030218 nuclear medicine & medical imaging ,law.invention ,User-Computer Interface ,0302 clinical medicine ,law ,Computer vision ,Zoom ,Gestures ,Angiography ,Signal Processing, Computer-Assisted ,General Medicine ,Equipment Design ,Computer Graphics and Computer-Aided Design ,Computer Science Applications ,Original Article ,Computer Vision and Pattern Recognition ,Algorithms ,Image View ,Movement ,0206 medical engineering ,Biomedical Engineering ,Neurosurgery ,Health Informatics ,Voice command device ,03 medical and health sciences ,Mode (computer interface) ,Imaging, Three-Dimensional ,Computer Systems ,Humans ,Radiology, Nuclear Medicine and imaging ,Computer Simulation ,Endovascular treatment ,Kinect ,business.industry ,Computers ,Volume rendering ,Intracranial Aneurysm ,Endovascular neurosurgery ,Hand ,020601 biomedical engineering ,Gesture recognition ,Surgery ,Artificial intelligence ,business ,Software - Abstract
Purpose In endovascular neurosurgery, the operator often acquires three-dimensional (3D) images of the cerebral vessels. Although workstation reoperation is required in some situations during treatment, it leads to time loss because a sterile condition cannot be maintained and treatment must be temporarily interrupted. Therefore, a workstation reoperating system is required while maintaining the desired sterility. Methods A contactless operating interface using Kinect to control 3D images was developed via gesture recognition for endovascular neurosurgery and was applied to a 3D volume rendering technique (VRT) image reconstructed at the workstation. The left-hand movement determines the assigned functions, whereas the right-hand movement is used like a computer mouse to pan and zoom in/out. In addition to the interface, voice commands were used and assigned to digital operations, such as image view changes and mode signal changes. Results This system was used for the actual endovascular treatment of cerebral aneurysms and cerebral arteriovenous malformations. The operator and gesture were recognized without any problems. Using voice operation, it was possible to expeditiously set the VRT image back to the reference angle. Furthermore, it was possible to finely adjust gesture operations, including mouse operation, and treatment was completed while maintaining sterile conditions. Conclusion A contactless operating interface was developed by combining the existing workstation system with Kinect and voice recognition software, allowing surgeons to perform a series of operations, which are normally performed in a console room, while maintaining sterile conditions. Supplementary Information The online version contains supplementary material available at 10.1007/s11548-021-02330-3.
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- 2020
22. Improved Performance of Nano-Sized Polyoxometalate as Lithium-Battery Cathode by Conductive Polymer Coating
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Erfe Ni, Qing Wen, Tetsuya Tsukada, and Noriyuki Sonoyama
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Conductive polymer ,Materials science ,Renewable Energy, Sustainability and the Environment ,Nanotechnology ,02 engineering and technology ,engineering.material ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,01 natural sciences ,Lithium battery ,Cathode ,0104 chemical sciences ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials ,law.invention ,Improved performance ,Coating ,law ,Polyoxometalate ,Materials Chemistry ,Electrochemistry ,engineering ,0210 nano-technology ,Nano sized - Published
- 2018
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23. The Treatment Outcome of Transarterial Embolization for Isolated Sinus Type Dural Arteriovenous Fistula between NBCA and Onyx
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Yosuke Tamari, Mamoru Ishida, Tetsuya Tsukada, Shigeru Miyachi, Masahiro Nishihori, Takashi Izumi, Toshihiko Wakabayashi, Masaki Sato, Noriaki Matsubara, Masashi Ito, and Tasuku Imai
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medicine.medical_specialty ,business.industry ,N-butyl-cyanoacrylate ,Treatment outcome ,Arteriovenous fistula ,medicine.disease ,030218 nuclear medicine & medical imaging ,Surgery ,03 medical and health sciences ,0302 clinical medicine ,medicine.anatomical_structure ,Transarterial embolization ,medicine ,Neurology (clinical) ,Radiology ,Cardiology and Cardiovascular Medicine ,business ,030217 neurology & neurosurgery ,Sinus (anatomy) - Published
- 2017
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24. A Case of Lateral Medullary Artery Arisen from the Posterior Meningeal Artery
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Tetsuya Tsukada, Toshihiko Wakabayashi, Masahiro Nishihori, Mamoru Ishida, Tasuku Imai, Asuka Elisabeth Kropp, Takashi Izumi, Masashi Ito, and Yousuke Tamari
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medicine.medical_specialty ,business.industry ,Posterior meningeal artery ,Medullary Artery ,03 medical and health sciences ,0302 clinical medicine ,030220 oncology & carcinogenesis ,medicine.artery ,Internal medicine ,Ischemic stroke ,Cardiology ,medicine ,Neurology (clinical) ,Cardiology and Cardiovascular Medicine ,business ,030217 neurology & neurosurgery - Published
- 2017
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25. Comparison of hemodynamic stress in healthy vessels after parent artery occlusion and flow diverter stent treatment for internal carotid artery aneurysm.
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Tetsuya Tsukada, Takashi Izumi, Haruo Isoda, Masahiro Nishihori, Kropp, A. Elisabeth, Takashi Mizuno, and Toshihiko Wakabayashi
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- 2022
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26. Factors influencing blood flow resistance from a large internal carotid artery aneurysm revealed by a computational fluid dynamics model
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Tasuku, Imai, Takashi, Izumi, Haruo, Isoda, Kenta, Ishiguro, Takashi, Mizuno, Tetsuya, Tsukada, Asuka, Kropp, Masashi, Ito, Masahiro, Nishihori, Mamoru, Ishida, Yosuke, Tamari, and Toshihiko, Wakabayashi
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Original Paper ,cardiovascular system ,Hydrodynamics ,pressure loss ,Humans ,Intracranial Aneurysm ,cardiovascular diseases ,Postoperative Period ,computational fluid dynamics ,Models, Theoretical ,large internal carotid artery aneurysm ,Carotid Artery, Internal - Abstract
Hyperperfusion syndrome occurs after treatment of a large or giant cerebral aneurysm. Recently, flow-diverter stent placement has emerged as an effective treatment method for a large cerebral aneurysm, but postoperative ipsilateral delayed intraparenchymal hemorrhage occurs in a minority of cases. The mechanism underlying delayed intraparenchymal hemorrhage is not established, but one possibility is hyperperfusion syndrome. The incidence of delayed intraparenchymal hemorrhage appears to be higher for giant aneurysms; hence, we speculated that large/giant aneurysms may create flow resistance, and mitigation by flow-diverter stent deployment leads to hyperperfusion syndrome and delayed intraparenchymal hemorrhage. The purpose of this study was to identify aneurysm characteristics promoting flow resistance by the analysis of pressure loss in an internal carotid artery paraclinoid aneurysm model using computational fluid dynamics. A virtual U-shaped model of the internal carotid artery siphon portion was created with a spherical aneurysm of various angles, body diameters, and neck diameters. Visualization of streamlines, were calculated of pressure loss between proximal and distal sides of the aneurysm, and vorticity within the aneurysm were calculated. The pressure loss and vorticity demonstrated similar changes according to angle, peaking at 60°. In contrast, aneurysm diameter had little influence on pressure loss. Larger neck width, however, increases pressure loss. Our model predicts that aneurysm location and neck diameter can increase the flow resistance from a large internal carotid artery aneurysm. Patients with large aneurysm angles and neck diameters may be at increased risk of hyperperfusion syndrome and ensuing delayed intraparenchymal hemorrhage following flow-diverter stent treatment.
- Published
- 2019
27. Lithium intercalation into polyoxomolybdate (NH4)6[NiMo9O32] as the cathode material of lithium battery
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Tetsuya Tsukada, Shinya Uematsu, Noriyuki Sonoyama, and Erfu Ni
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Materials science ,Nanocomposite ,chemistry.chemical_element ,Nanotechnology ,02 engineering and technology ,General Chemistry ,Carbon black ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,01 natural sciences ,Cathode ,Lithium battery ,0104 chemical sciences ,law.invention ,Amorphous solid ,chemistry ,Chemical engineering ,law ,General Materials Science ,Lithium ,Particle size ,0210 nano-technology ,Current density - Abstract
Molecular cluster ion material, polyoxomolybdate (NH 4 ) 6 [NiMo 9 O 32 ] (ANM), was utilized as a new cathode material of lithium battery. Discharge capacity and cycle performance of ANM largely depend on the particle size and type of conductive additive. Nanosize ANM particles (~ 100 nm) can be easily prepared by a simple re-crystallization method. Ketjen black (KB) conductive additive shows much more effectiveness than acetylene black (AB) conductive additive in improving discharge capacity and cycle performance of nanosize particles. Nanosize particles hand-ground with KB show high initial discharge capacity of 490 mAh g − 1 and capacity retention of 87.6% after 50 cycles at the current density of 17 mA g − 1 . ANM in situ re-crystallized in the micropores or mesopores of KB (nanocomposite ANM/KB) shows improved discharge capacity at the high current densities but poor cycle stability at the low current densities, compared to nanosize particles hand-ground with KB. Ex situ XRD measurement reveals that the crystal structure of ANM becomes amorphous in the first discharge process and shows irreversibility in the following charge process. This result indicates that the insertion–extraction of lithium ion in the cathode is independent from the crystal structure.
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- 2016
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28. Case-control study of postprocedural arterial puncture site hemorrhage after neuroendovascular treatment.
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Yosuke Tamari, Takashi Izumi, Masahiro Nishihori, Tasuku Imai, Masashi Ito, Tetsuya Tsukada, Mamoru Ishida, and Toshihiko Wakabayashi
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ENDOVASCULAR surgery ,HEMORRHAGE ,FEMORAL artery ,ARTERIAL injuries ,ANTICOAGULANTS - Abstract
Puncture site hemorrhage following femoral artery catheterization is a significant cause of morbidity. The aim of this case-control study was to identify predictors of postprocedural arterial hemorrhage at the puncture site. We retrospectively reviewed 255 patients who underwent endovascular treatment at our institution over a 23-month period and classified them into a hemorrhage group and a non-hemorrhage group. Puncture site hemorrhage occurred in 15 patients (5.9%). Clinical factors associated with a significantly increased risk of puncture site bleeding included patients whose postoperative activated clotting time of ≥300 seconds before removal of the sheath (9 patients, 11.8%; P<0.05), those who received triple antiplatelet therapy (n=4, 17.4%; P<0.05) and the group administered heparin postoperatively (7 patients, 13.2%; P<0.05). The effects of low on-treatment platelet reactivity, i.e., P2Y12 reaction units <95%, sheath size, hemostasis method used, and operating time were not clinically significant. Our findings suggest an increased risk of puncture site hemorrhage in patients who either had an activated clotting time ≥300 seconds before the postoperative removal of the sheath, had received triple antiplatelet therapy, or were administered heparin postoperatively. [ABSTRACT FROM AUTHOR]
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- 2021
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29. A case of internal trapping to a thrombosed giant rapidly growing aneurysm at the posterior cerebral artery.
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Masato Otawa, Takashi Izumi, Masahiro Nishihori, Tetsuya Tsukada, Ryosuke Oshima, Tomomi Kawaguchi, Shunsaku Goto, Mizuka Ikezawa, Asuka Elisabeth Kropp, Yoshio Araki, Kinya Yokoyama, Kenji Uda, and Toshihiko Wakabayashi
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CEREBRAL arterial diseases ,ANEURYSM diagnosis ,THROMBOSIS ,COMPUTED tomography ,MAGNETIC resonance imaging - Abstract
We describe a case of internal trapping including the vasa vasorum for a thrombosed giant rapidly growing posterior cerebral artery aneurysm and performing a detailed analysis. A 48-year-old woman was followed up in our hospital for a thrombosed large posterior cerebral artery aneurysm located in the P2 segment. She initially presented after experiencing a sudden headache on two occasions. Head computed tomography and magnetic resonance imaging indicated a larger aneurysm than before. Digital subtraction angiography with balloon occlusion test was assessed, and internal trapping was sequentially conducted. We detected that the vasa vasorum originated from the posterior temporal artery. Therefore, we embolized the posterior temporal artery including the vasa vasorum using N-butyl-2-cyanoacrylate and Lipiodol. Next, the anterior temporal artery was embolized with N-butyl-2-cyanoacrylate and Lipiodol, posterior temporal artery P3 segment and the aneurysm and finally the proximal P2 segment were embolized with coils. Final vertebral and internal carotid angiography showed complete obliteration of the aneurysm. On the day after the procedure her paresis worsened and she developed left upper quadrantanopia, however was finally discharged with no hemiparesis. We reported a case of a rapidly growing thrombosed giant posterior cerebral artery aneurysm treated by parent artery occlusion including the vasa vasorum with detailed image analysis. [ABSTRACT FROM AUTHOR]
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- 2020
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30. Cognitive psychological approach for an effective Shisa-Kosyo in a field depended on human memory function
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Jun Kawaguchi, Masaru Hikono, Hajime Nakamura, Hama Watanabe, Tetsuya Tsukada, and Yusuke Nakai
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Field (Bourdieu) ,media_common.quotation_subject ,Human memory ,Cognition ,Psychology ,Function (engineering) ,Cognitive psychology ,media_common - Abstract
本研究では, プラントにおける作業を模擬した二つの実験を通して, 行為意図の遂行における事前動作の効果を検討した. 各実験にはそれぞれ40名, 20名の学部学生が参加した. 両方の実験で, 被験者は指示 (例えば“112A 開”) を与えられ, それらを覚えるよう教示された. 干渉課題に続いて, 被験者はキーボードキーを押すことで指示を遂行することが求められた. 六つの指差呼称条件 (統制条件・動作付き指差呼称条件・動作付き指差条件・呼称条件・指差呼称条件・位置確認条件) を比較した結果, 動作付き指差呼称もしくは指差呼称を伴って指示書を確認した被験者において, 優れた遂行成績が示された. これらの結果は, 作業前に作業遂行時と同様の動作を行うことが, 通常の指差呼称と同程度に, 意図した行為の優れた遂行を導くことを示唆している.
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- 2005
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31. Colonic and peritoneal tuberculosis associated with coloduodenal fistula
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Katsuhiro Kawamura, Hiromi Aonuma, Takayuki Matsumoto, Masayuki Kusagawa, Tetsuya Tsukada, Shigeo Nakazawa, Nobuhiro Ishida, Takaaki Nishioka, Takao Sekine, Yoshihiro Okabayashi, Takeshi Shimizu, Kazuhiko Kobayashi, Kazuo Izumi, Yoshiyuki Ando, Mitsuya Noguchi, and Hidetsugu Mitani
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Adult ,medicine.medical_specialty ,Tuberculosis ,Fistula ,Peritonitis, Tuberculous ,Gastroenterology ,Hepatic Flexure ,Colonic Diseases ,Internal medicine ,Ascites ,Intestinal Fistula ,medicine ,Humans ,Duodenal Diseases ,Colitis ,business.industry ,Hepatology ,medicine.disease ,Colorectal surgery ,Surgery ,Tuberculosis, Gastrointestinal ,Female ,medicine.symptom ,business ,Abdominal surgery - Abstract
We report a very rare case of tuberculous colitis that showed relatively long-segment involvement of the colon near the hepatic flexure with coloduodenal fistula that caused severe malnutrition. The formation of fistula in abdominal tuberculosis is very rare. This is the eighth reported case of abdominal tuberculosis with fistula and the first reported case with a coloduodenal fistula.
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- 1995
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32. Improvement of Electrochemical Property of Molecular Cluster Ion Cathode Material for Lithium Battery
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Noriyuki Sonoyama, Tetsuya Tsukada, and Erfu Ni
- Abstract
Polyoxometalates (POM) are very famous cluster ions that can be synthesized self-assembly formation in the solution. These cluster ions behave as independent molecules and show reversible redox activity in the solution. These molecular cluster ions are expected to show different property from the usual cathode materials for lithium ion battery those are the bulk continuum ionic crystals.[1-3] In this paper, we have synthesized Anderson-type POM Na3[AlMo6O24H6] (Fig.1 ) and examined its electrochemical property as cathode materials for lithium battery. In Anderson-type POM, all [MoO6] share the edge with hetero ion [AlO6]. This covalent bond of [MoO6] with unreactive hetero ion would stabilize the structure of the reduced POM. Anderson-type POMs were synthesized according to the reported method. [4] Obtained samples were mixed with acetylene black with the weight ratio of 1:2 using ball mill. The charge-discharge test and AC-impedance spectra measurements are performed using the coin cells at 25ºC. Lithium metal was used as anode and 1M solution of LiPF6in EC:DEC (3:7 v/v%) was used as the electrolyte. After the charge-discharge measurements, ex-situ XRD and Raman measurements were carried out under Ar atmosphere again. NMR, FT-IR and Raman spectra of obtained samples agreed with those for reported Anderson-type POM. In Fig. 1, the discharge-charge curves for Na3AlMo6O24H6 were shown. Na3AlMo6O24H6 mixed by ball mill show large capacity over 420 mAh/g. In Fig.2, cycle stability of Na3AlMo6O24H6 was shown. The cycle stability of Na3AlMo6O24H6 was higher than the most representative POM K3PMo12O40 with Keggin type structure. 90% of the initial discharge capacity for Anderson-type POM was retained after 50 cycles, whereas that for KPM decreased steeply in the first 10 cycles. This result suggests Anderson type POM has higher stability than Keggin type POM. In the presentation, methods for further improvement of the electrochemical property of POM will be explained. [1] N. Sonoyama et al, J. Power Sources, 196 (2011) 6822. [2] S. Uematsu et al, , J. Power Sources, J. Power Sources, 217, (2012)13. [3] E. Ni et al. J Nanopart Res, 15(2013) 1732. [4] Kenji Nomiya et al. Polyhedron, (1987) 213. Figure 1
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- 2016
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33. New Conversion Anode Material Utilizing Redox of Al3+ Ion
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Noriyuki Sonoyama, Yoshitaka Ogasawara, Tomokatsu Aoi, Satoshi Yoshida, and Tetsuya Tsukada
- Abstract
A new conversion type anode material for lithium ion battery utilizing the redox activity of aluminum (III) ion has developed. Conversion type materials are known to have a serious weak point as anode materials, that is the high reaction voltage in spite of its high capacity (over 600 mAh/g). This high reaction voltage originates in high redox potential of transition metal oxide such as NiO or CoO, those are known as representative conversion anode materials for lithium ion battery. In order to improve this high reaction voltage, it is effective to use oxides of light metal with lower redox potentials such as aluminum oxides. However, aluminum oxides are difficult to use as the electrode materials owing to the low electric and ionic conductivity. We have synthesized solid solution of nickel oxide and aluminum oxide with nano level particle size by calcination of Ni-Al layered double hydroxides (LDH). The fine structure of calcinated materials are determined by XRD and XAFS: Ni2+ and Al3+ ions are randomly locating metal ion sites of NiO with rock salt structure and cation vacancies are introduced to compensate the excessive charges brought by the aluminum ions. In this structure, electron and lithium ion are expected to be supplied via NiO type host structure and cation vacancies, respectively. The charging capacity of the half cell with lithium metal counter electrode from 0.03 V to I.5 V, that corresponds to the discharge capacity or the full cell was improved to 600 mAh/g, where as that for pristine NiO was 230 mAh/g. This improvement of capacity in the lower voltage region is expected to originate in redox of aluminum ion. The redox activity of aluminum ion was confirmed by ex-situ XANES measurement at Al K edge. The absorption edge of aluminum ion shifted to lower energy direction with discharge from 1560 keV to 1556 keV. With charging (the absorption edge of aluminum shifted back to the initial position. This dearly indicates the redox activity of aluminum ion during charge- discharge. This is the first report of anode material for lithium battery that utilizes redox of aluminum ion as far as we know. In order to investigate the detailed reaction mechanism, ex-situ XRD and XAFS measurements were, carried out. On the basis of these results, the reaction mechanism of Ni-Al binary metal oxide was concluded as follows. In the higher voltage discharge process (OCV-1.0 V), lithium intercalation into the cation vacancy and lithium ion adsorption to the surface of Ni-Al binary metal oxide with the partial redaction of nickel ion is proceeding. In the lower voltage discharge (1.0-0.03 V), the conversion reaction proceeds with the reduction of Ni and Al ions. In the lower voltage charge process (0.03-1.0 V), only aluminum ion is oxidized to form an intermediate state, where aluminum ion makes complex with surrounding oxide ions. In the higher voltage charge process, nickel metal is oxidized to re-form the Ni-Al binary metal oxide with the rock salt structure.
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- 2016
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34. Synthesis and electrochemical properties of nanosized polyoxovanadate K<SUB align='right'>7[NiV<SUB align='right'>13O<SUB align='right'>38] hybridised with carbon conductive additives
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Tetsuya Tsukada, Erfu Ni, and Noriyuki Sonoyama
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Materials science ,020209 energy ,chemistry.chemical_element ,Bioengineering ,Nanotechnology ,02 engineering and technology ,Carbon black ,Electrolyte ,Condensed Matter Physics ,Electrochemistry ,chemistry ,Chemical engineering ,Electrical resistivity and conductivity ,Polyoxometalate ,0202 electrical engineering, electronic engineering, information engineering ,Materials Chemistry ,Nanometre ,Electrical and Electronic Engineering ,Carbon ,Dissolution - Abstract
Improvement in the electrochemical property of polyoxovanadate K7[NiV13O38] (KNV) was attempted by downsizing to nanometre order by simple re-crystallisation and mixing or hybridising it with Ketjen black (KB) that has higher electric conductivity and surface area than acetylene black (AB). By mixing nanosize KNV with KB, the discharge capacity was improved up to 500 mAh/g, whereas capacity for micro-size KNV mixed with AB was limited to ∼120 mAh/g. The cycle performance and rate performance of KNV were also improved by downsizing and mixing with KB. On the other hand, KNV hybridised with KNV by in situ re-crystallisation showed lower cycle performance. This low cycle stability may be concerning with the surface sub-reaction such as surface film formation produced by the reaction with the electrolyte solution and/or dissolution of KNV, those are enhanced by increase with contacting surface area with the electrolyte.
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- 2016
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35. Remarkable activation of polyamine biosynthesis in hematopoiesis and hyperplasia of spleen in mice with Hemolytic anemia caused by infection with Plasmodium berghei
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Sakurai M, Yutaka Nishiguchi, Kunio Nakashima, Hiroshige Hibasami, Tetsuya Tsukada, and Shigeru Shirakawa
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Male ,Hemolytic anemia ,Anemia, Hemolytic ,medicine.medical_specialty ,genetic structures ,Plasmodium berghei ,Spermine ,Spleen ,Ornithine Decarboxylase ,Ornithine decarboxylase ,Mice ,chemistry.chemical_compound ,Internal medicine ,parasitic diseases ,Polyamines ,medicine ,Animals ,Mice, Inbred BALB C ,Hyperplasia ,biology ,fungi ,biology.organism_classification ,medicine.disease ,Hematopoiesis ,Malaria ,Haematopoiesis ,Infectious Diseases ,medicine.anatomical_structure ,Endocrinology ,chemistry ,Splenomegaly ,Immunology ,Putrescine ,Parasitology ,Polyamine - Abstract
Ornithine decarboxylase (ODC) activity was markedly induced in the spleen of mice infected with Plasmodium berghei, showing maximal activity at 8 days after the infection. The increase of spleen weight, on the other hand, reached its peak after 14 days of infection. In the blood of P. berghei-infected mice, no increase of ODC activity was observed. This indicated that ODC was induced in the spleen cells, but not in the parasites themselves which existed in the blood. Polyamines (putrescine, spermadine and spermine) were also elevated in the spleen following induction of the ODC activity. On the other hand, increases of ODC activity and spleen weight were observed in the spleen of mice with hemolytic anemia induced by acetylphenylhydrazine, but the extent of these increases were smaller than those in the spleen of mice infected with P. berghei. The present results suggest that increases in ODC activity and polyamine levels in the spleen of P. berghei-infected mice are related to hyperplasia of the spleen (splenomegaly) where the formation of leukocytes and erythrocytes (hematopoiesis) was dramatically stimulated by the infection.
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- 1994
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36. Successful Continuous Treatment with All-Trans Retinoic Acid for Acute Promyelocytic Leukemia; Secondary Malignancy after the Treatment of Osteosarcoma
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Nadim Mahmud, Tetsuya Tsukada, Kenkichi Kita, Takao Sekine, Tohru Kobayashi, Masanori Taniguchi, H Kihira, Shigeru Shirakawa, Katsumi Deguchi, Hiroshi Miwa, and Takahiro Takahashi
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Male ,Acute promyelocytic leukemia ,Adolescent ,medicine.medical_treatment ,Retinoic acid ,Tretinoin ,chemistry.chemical_compound ,Leukemia, Promyelocytic, Acute ,Antineoplastic Combined Chemotherapy Protocols ,Internal Medicine ,medicine ,Humans ,Adverse effect ,neoplasms ,Etoposide ,Osteosarcoma ,Chemotherapy ,business.industry ,Femoral Neoplasms ,organic chemicals ,Secondary Malignancy ,Neoplasms, Second Primary ,General Medicine ,medicine.disease ,biological factors ,Continuous treatment ,chemistry ,Immunology ,Cancer research ,business ,medicine.drug - Abstract
We report a rare case of complete remission for 32 months with continuous treatment with all-trans retinoic acid (ATRA) alone in a patient with acute promyelocytic leukemia which developed as a second malignancy after the treatment of osteosarcoma after failure of conventional chemotherapy. The adverse effects of ATRA were apparently tolerable.
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- 1994
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37. Tooth extraction using a recombinant human factor VIII preparation (BAY w 6240) in a patient with hemophilia a
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Tohru Kobayashi, Nobuyuki Minami, Hideo Wada, Tetsuya Tsukada, Hiroshi Deguchi, Katsumi Deguchi, Thoshiro Tagawa, Shigeru Shirakawa, and Hiroyuki Kihira
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Pharmacology ,business.industry ,Recombinant human factor VIII ,Extraction (chemistry) ,Dentistry ,medicine.disease ,law.invention ,Clinical study ,Pharmacokinetics ,law ,hemic and lymphatic diseases ,Recombinant DNA ,Coagulopathy ,Medicine ,Pharmacology (medical) ,In patient ,business ,Factor VIII preparation - Abstract
Within the framework of a multicenter clinical study of the recombinant human factor VIII preparation BAY w 6240, we studied the pharmacokinetics of this factor in blood by using the preparation during tooth extraction in a patient with hemophilia A. The results allowed us to conclude that this preparation exerts a hemostatic effect comparable to that of human-derived concentrated factor VIII preparation and that it can be safely used in patients with hemophilia A who undergo tooth extraction.
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- 1993
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38. Randomized study of individualized induction therapy with or without vincristine, and of maintenance—intensification therapy between 4 or 12 courses in adult acute myeloid leukemia. AML-87 study of the Japan adult leukemia study group
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Hidehiko Saito, Norio Asou, Mitsune Tanimoto, Hirokazu Murakami, Kazuo Tsubaki, Akira Hiraoka, Saburo Minami, Koji Fujimoto, Kazutaka Kuriyama, Tomoki Naoe, Tetsuya Tsukada, Tohru Masaoka, Isao Takahashi, Ikuro Kimura, Tohru Kobayashi, Tohru Tahara, Masao Tomonaga, Masanori Shimoyama, Kuniyuki Imai, Hirofumi Teshima, Shigeru Shirakawa, Minoru Yoshida, Yasusuke Onozawa, Ryuzo Ohno, Shinichi Kageyama, Atsushi Horiuchi, Yoshihisa Kodera, Takaaki Takeo, and Yasusada Miura
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Cancer Research ,medicine.medical_specialty ,Vincristine ,Performance status ,business.industry ,Adult Acute Myeloid Leukemia ,medicine.disease ,law.invention ,Surgery ,Leukemia ,Oncology ,Randomized controlled trial ,Maintenance therapy ,law ,Internal medicine ,Remission Induction Therapy ,Prednisolone ,Medicine ,business ,medicine.drug - Abstract
Background. It was assessed whether addition of vincristine (VCR) to remission induction therapy would increase the complete remission (CR) rate, and, secondarily, whether 12 courses of maintenance—intensification therapy would produce longer survival than 4 courses in adult acute myeloid leukemia (AML). Methods. A randomized comparison of individualized induction therapy was conducted between daunorubicin, behenoyl cytarabine, 6-mercaptopurine, and prednisolone with or without VCR. After 3 courses of intensive consolidation therapy, maintenance—intensification therapy was randomized to 4 or 12 courses given every 6 weeks. Results. Of 265 patients registered, 252 were evaluable. CR was obtained in 78%; 80% in 205 patients of age younger than 60 years, and 65% in 47 of age 60 years or older. Addition of VCR reduced the CR rate significantly (84% to 70%, P = 0.007). Predicted 4-year survival, continuing CR, and disease-free survival (DFS) rates of 196 CR patients are 45%, 41%, and 35%, respectively. Patients receiving 12 courses of maintenance—intensification showed better DFS. By multivariate analyses, significant factors for achievement of CR were performance status 0 to 2, age younger than 60 years, and no VCR; and those for longer DFS were achievement of CR by one course, age younger than 50 years, and French—American—British (FAB) classification M3 or M5. Among 131 patients randomized to the maintenance, the administration of 12 courses was the most important factor (P = 0.0040) for longer DFS, followed by FAB M3 or M5, and by achievement of CR by one course. Conclusions. Addition of VCR in remission induction therapy was harmful, and longer intensive maintenance therapy prolonged DFS in adult AML.
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- 1993
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39. CD5 Expression and Its Significance in B-Cell Lymphomas
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Tetsuya Tsukada, Toru Kobayashi, Shigeru Shirakawa, Toshiyuki Ohno, Motoko Yamaguchi, Kenkichi Kita, and Kouji Oka
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medicine.anatomical_structure ,Expression (architecture) ,medicine ,Biology ,CD5 ,Molecular biology ,B cell - Published
- 1993
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40. Fatal Trichosporon fungemia in patients with hematologic malignancies
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Naoyuki Katayama, Kei Suzuki, Yumiko Sugawara, Kouji Oka, Tadahiro Kohara, Kazunori Nakase, Tetsunori Shibazaki, Tetsuya Tsukada, and Taiichi Kyo
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Adult ,Male ,medicine.medical_specialty ,Antifungal Agents ,Adolescent ,Neutropenia ,Young Adult ,Trichosporon ,Internal medicine ,medicine ,Humans ,Blood culture ,Fungemia ,Aged ,Retrospective Studies ,Aged, 80 and over ,Acute leukemia ,medicine.diagnostic_test ,biology ,business.industry ,Micafungin ,Breakthrough infection ,Hematology ,General Medicine ,Middle Aged ,medicine.disease ,biology.organism_classification ,Trichosporonosis ,Mycoses ,Hematologic Neoplasms ,Immunology ,Female ,business ,medicine.drug - Abstract
Objective Invasive Trichosporon infection has been increasingly recognized in patients with hematologic malignancies. Our study aims to clarify the clinical characteristics of this disease and factors influencing patient prognosis. Patients and methods We retrospectively analyzed 33 cases of Trichosporon fungemia (TF) in patients with hematologic malignancies treated at our collaborating five hospitals in Japan between 1992 and 2007. Results The majority of these patients had acute leukemia (82%), neutropenia (85%), and a history of intensive chemotherapy (91%). TF occurred as a breakthrough infection during antifungal therapy in 30 patients (91%), 18 of whom were receiving micafungin. The surveillance cultures of most patients were negative for Trichosporon. Only a few patients exhibited elevated levels of 1,3-beta-d-glucan before positive blood culture. Twenty-five patients (76%) died of this infection. The resolution of infection was associated with neutrophil recovery (P = 0.0001), absence of hyperglycemia (P = 0.023), and azole inclusive therapy (P = 0.031). Survival was significantly longer in patients receiving antifungal therapies containing azole than in those who did not receive azole (P = 0.0034). Conclusions At present, the diagnosis of invasive trichosporonosis depends on blood culture studies, and the mortality of this disease is high; however, azole therapy and control of blood glucose level, together with hematopoietic recovery could help in improving the clinical outcome. When we use antifungals lacking anti-Trichosporon activity, sufficient care should be taken to prevent the development of breakthrough trichosporonosis.
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- 2010
41. Primary Esophageal Non-Hodgkin's Lymphoma
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Kenkichi Kita, Hajime Yokoi, Shinobu Arima, Tohru Kobayashi, Hiroyuki Yamada, Takahiro Takahashi, Masanori Taniguchi, Tetsuya Tsukada, Shigeru Shirakawa, Toshiyuki Ohno, H Kihira, and Yoshikazu Akasaka
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medicine.medical_specialty ,Pathology ,Esophageal Neoplasms ,medicine.medical_treatment ,CHOP ,Gastroenterology ,Swallowing ,hemic and lymphatic diseases ,Internal medicine ,Antineoplastic Combined Chemotherapy Protocols ,Internal Medicine ,medicine ,Humans ,T-cell lymphoma ,Esophagus ,Cyclophosphamide ,Aged ,Upper gastrointestinal series ,business.industry ,General Medicine ,medicine.disease ,Combined Modality Therapy ,Non-Hodgkin's lymphoma ,Lymphoma ,Radiation therapy ,medicine.anatomical_structure ,Doxorubicin ,Vincristine ,Prednisone ,Female ,Lymphoma, Large B-Cell, Diffuse ,business - Abstract
A 77-year-old woman with primary esophageal non-Hodgkin's lymphoma in clinical stage IEA (Ann Arbor Classification) developed pain and difficulty in swallowing. An upper gastrointestinal examination revealed a submucosal tumor from the upper to the middle portion of the esophagus. Histopathological examination at endoscopic biopsy with endoscopic partial incision showed non-Hodgkin's lymphoma (diffuse type--large cell). Immunohistological examination of tumor cells disclosed LCA (+), CD3(DAKO) (+), MT1 (+), UCHL1 (+), MB1 (+), MxPanB (-) and EMA (-) reactivity and showed T cell lymphoma. The clinical stage was determined to be IEA after further work-up. Improvement of swallowing difficulty and esophageal findings on upper gastrointestinal series were noted after modified CHOP therapy and radiotherapy (total 50 Gy).
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- 1992
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42. An adult case of acute lymphoblastic leukemia with necrotizing leukoencephalopathy
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Tetsuya Tsukada, Masakatsu Nishikawa, Naoyuki Katayama, Tohru Kobayashi, Morita N, Shigeru Shirakawa, Katsumi Deguchi, and Ikeda T
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Adult ,Male ,medicine.medical_specialty ,Pediatrics ,Lymphoblastic Leukemia ,medicine.medical_treatment ,Leukoencephalopathy ,Necrosis ,X ray computed ,hemic and lymphatic diseases ,medicine ,Humans ,Radionuclide Imaging ,Intensive care medicine ,Chemotherapy ,business.industry ,Leukoencephalopathy, Progressive Multifocal ,Adult case ,General Medicine ,Precursor Cell Lymphoblastic Leukemia-Lymphoma ,medicine.disease ,Leukemia ,Methotrexate ,Common Acute Lymphoblastic Leukemia ,Tomography, X-Ray Computed ,business ,medicine.drug - Abstract
A 19-year-old man with common acute lymphoblastic leukemia (ALL) developed necrotizing leukoencephalopathy (NL) after extensive chemotherapy and irradiation. Clinicians should exercise care in the treatment of leukemia, since chemotherapy has shown a trend of becoming more intensive, and the survival time of patients with leukemia is being extended.
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- 1990
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43. Effects of atorvastatin on serum lipids, lipoproteins, and hemostasis
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Tetsuya Tsukada, Kinue Ooi, Akane Sakaguchi, Yasunori Abe, Takahiro Nakasaki, Fumihiko Kushiya, Hiroshi Shiku, Hideo Wada, Tsutomu Nobori, Maki Noda, and Yuko Sakurai
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Adult ,Male ,medicine.medical_specialty ,Very low-density lipoprotein ,Atorvastatin ,Lipoproteins ,Blood lipids ,Hyperlipidemias ,Thrombomodulin ,chemistry.chemical_compound ,Internal medicine ,Hyperlipidemia ,polycyclic compounds ,medicine ,Humans ,Pyrroles ,Anion Exchange Resins ,Aged ,Electrophoresis, Agar Gel ,Hemostasis ,medicine.diagnostic_test ,Triglyceride ,Chemistry ,technology, industry, and agriculture ,Imidazoles ,nutritional and metabolic diseases ,Hematology ,Middle Aged ,medicine.disease ,Lipids ,Resins, Synthetic ,Endocrinology ,Heptanoic Acids ,lipids (amino acids, peptides, and proteins) ,Epichlorohydrin ,Female ,Hydroxymethylglutaryl-CoA Reductase Inhibitors ,Partial thromboplastin time ,medicine.drug ,Lipoprotein - Abstract
Serum levels of lipids and lipoproteins were examined in individuals with hyperlipidemia treated with atorvastatin or colestimide and in healthy volunteers. Modified low-density lipoprotein (LDL) was measured by its faster electrophoretic mobility and expressed as charge modification frequency (CMF). Serum levels of total cholesterol (t-chol), triglyceride (TG), very low-density lipoprotein (VLDL)-chol, low-density lipoprotein (LDL)-chol, and CMF were significantly higher in hyperlipidemia, but there was no significant difference in serum high-density lipoprotein (HDL)-chol levels between hyperlipidemic and healthy subjects. Treatment with atorvastatin resulted in significant decreases of serum t-chol, TG, and LDL-chol levels but not serum HDL-chol and VLDL-chol. Treatment with colestimide significantly reduced serum t-chol, HDL-chol, and LDL-chol levels but not those of TG and VLDL-chol. CMF was significantly reduced by treatment with atorvastatin but not by colestimide. Atorvastatin significantly reduced plasma levels of thrombomodulin, thrombin antithrombin complex (TAT) and tissue type plasminogen activator-plasminogen activator inhibitor-I complex. Colestimide moderately prolonged activated partial thromboplastin time and reduction of TAT. Based on its actions of lowering modified LDL and improving hemostatic abnormalities, we postulate that atorvastatin might inhibit the onset of ischemic diseases.
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- 2004
44. Sharing Knowledge on Human Error Prevention
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TETSUYA TSUKADA and FUMIO KOTANI
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- 2001
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45. Growth inhibition of Candida by 15-deoxyspergualin, an immunosuppressive agent used in experimental organ transplantation
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Kunio Nakashima, M. Imai, Tetsuya Tsukada, Hitoshi Yoshimura, P. Gasaluck, Shigeru Shirakawa, Hiroshige Hibasami, and Y. Midorikawa
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biology ,Spermine ,Pharmacology ,biology.organism_classification ,Applied Microbiology and Biotechnology ,Corpus albicans ,Microbiology ,Spermidine ,Transplantation ,chemistry.chemical_compound ,chemistry ,Putrescine ,Growth inhibition ,Candida albicans ,Polyamine - Abstract
The metabolic and antiproliferative effects of 15-deoxyspergualin (DSG), an immunosuppressive agent used in experimental organ transplantation, on Candida albicans were investigated. The minimal inhibitory concentration of DSG for C. albicans was 31·3 μg/ml and it depleted intracellular putrescine, spermidine and spermine to 57, 55 and 71% of control levels, respectively. In such polyamine-depleted cells, the synthesis of DNA. RNA and protein were decreased to 56, 71 and 79% of the control. This suggests that the depression of intracellular polyamines by this drug may be a cause of the suppression of macromolecule biosyntheses and of growth of C. albicans.
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- 1992
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46. Successful Treatment with Imatinib Combined with Less Intensive Chemotherapy (Vincristine and Dexamethasone) as Induction Therapy in a Very Elderly Patient with Philadelphia Chromosome-Positive Acute Lymphoblastic Leukemia
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Tetsuya Tsukada, Naoyuki Katayama, Hyou Ryuu, Kazuhiro Nishii, and Miho Sakakura
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Oncology ,medicine.medical_specialty ,Vincristine ,Hematology ,Philadelphia Chromosome Positive ,business.industry ,Lymphoblastic Leukemia ,Imatinib ,Intensive chemotherapy ,Internal medicine ,Induction therapy ,medicine ,business ,Dexamethasone ,medicine.drug - Published
- 2007
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47. Human factors as revealed by the use of natural language in near-incidents at nuclear power plants
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Fumio Kotani, Hirofumi Shinohara, and Tetsuya Tsukada
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Engineering ,business.industry ,Nuclear engineering ,Environmental resource management ,Nuclear power ,business ,Natural language - Published
- 1998
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48. Bilateral Osteonecrosis of the Head of the Femur during Treatment with Retinoic Acid in a Young Patient with Acute Promyelocytic Leukemia
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Tetsuya Tsukada, Hiroshi Shiku, Eiji Usui, Kazuhiro Nishii, Fumihiko Monma, and Miho Sakakura
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Adult ,Acute promyelocytic leukemia ,medicine.medical_specialty ,medicine.drug_class ,Retinoic acid ,Antineoplastic Agents ,Tretinoin ,Avascular necrosis ,Gastroenterology ,chemistry.chemical_compound ,Femoral head ,Leukemia, Promyelocytic, Acute ,Maintenance therapy ,Femur Head Necrosis ,immune system diseases ,Internal medicine ,medicine ,Humans ,Femur ,Retinoid ,neoplasms ,Hematology ,business.industry ,organic chemicals ,medicine.disease ,biological factors ,Surgery ,Radiography ,medicine.anatomical_structure ,chemistry ,Female ,business - Abstract
All-trans retinoic acid (ATRA) is the drug of choice for the treatment of acute promyelocytic leukemia (APL). In general, ATRA is well tolerated, but it does have side effects, the most severe of which is ATRA syndrome. We report the case of a young patient with APL treated with ATRA for induction and maintenance therapy who then developed avascular necrosis of both femoral heads. We also review cases of APL patients with osteonecrosis of the femoral head after ATRA therapy.
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- 2006
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49. Liver sarcoidosis showing low-density intrahepatic septa on postcontrast computed tomography
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Hiroshi Miwa, Hiromi Aonuma, Masanori Taniguchi, Tetsuya Tsukada, Nobuyasu Itoh, Tohru Kobayashi, Naoyuki Katayama, Katsumi Deguchi, and Shigeru Shirakawa
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Liver sarcoidosis ,Male ,medicine.medical_specialty ,Sarcoidosis ,business.industry ,Liver Diseases ,Gastroenterology ,Hepatology ,Middle Aged ,medicine.disease ,Precontrast ,Liver ,Sarcoidosis, Pulmonary ,Granuloma ,Internal medicine ,Pulmonary fibrosis ,medicine ,Humans ,Radiology ,Tomography ,business ,Tomography, X-Ray Computed ,Lung ,Aspergilloma - Abstract
The authors present a patient with massive liver sarcoidosis, showing only slight hepatomegaly on precontrast computed tomogram and multiple low-density intrahepatic septa on postocontrast computed tomogram. Sarcoidosis frequently involves the liver, but rarely shows abnormal findings other than hepatomegaly on computed tomograms. Only a few cases have demonstrated a low density intrahepatic area on computed tomograms1,2. In this report, we present a patient with massive liver and pulmonary sarcoidosis, showing low density intrahepatic septa and pulmonary fibrosis on computed tomograms.
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- 1993
50. Study on Hyperactivated State of Coagulation and Fibrinolysis
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Tetsuya Tsukada, K. Oonishi, Seikou Murashima, Katsumi Deguchi, and Nishikawa M
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Clotting factor ,medicine.medical_specialty ,business.industry ,medicine.medical_treatment ,medicine.disease ,Thrombosis ,Coagulation ,Internal medicine ,Fibrinolysis ,medicine ,Cardiology ,Blood supply ,Thrombus ,business ,Vital organ - Abstract
The excessive and untimely formation of blood clot(thrombus) in blood vessels may discontinue the blood supply to vital organ, and sometimes be followed by the aggravation of diseased state and the danger of life. The word “hypercoagulability” is often taken to mean an increased tendency to thrombose, and is usually used to mean an excess or activation of, clotting factors. Furthermore, as analogous words, prethrombotic state seem to imply the previous state of thrombosis, and prethrombotic state is used to connote a predisposition to thrombose(1). It is very important for the prophylaxis of overt thrombosis to know the behaviors of clotting and fibrinolytic factors in these state.
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- 1993
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