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Fukutomi D, Ishii K, Awazu K. Highly accurate scattering spectra of strongly absorbing samples obtained using an integrating sphere system by considering the angular distribution of diffusely reflected light. Lasers Med Sci 2015; 30:1335-40. [PMID: 25772249 DOI: 10.1007/s10103-015-1734-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2014] [Accepted: 02/25/2015] [Indexed: 11/30/2022]
Abstract
An integrating sphere system has been used to investigate the estimation error in the scattering coefficient for biological tissues. Since the angular distribution of diffusely reflected light from a sample may depend on the sample absorbance, leakage at the entrance port may affect estimates of the scattering coefficient based on measurement of diffuse reflectance. In the present study, the dependence of the angular distribution of the diffusely reflected light on the hemoglobin (Hb) concentration in a sample was investigated. Subsequently, the effect of the entrance port diameter on the error in the scattering coefficient estimated based on diffuse reflectance measurements was evaluated. For a biological tissue phantom, the angular reflectance distribution at a wavelength of 405 nm, at which strong absorption occurred, showed an increasing bias toward specular reflection as the Hb concentration was increased. No such concentration dependence was found at a wavelength of 664 nm, where the absorbance was low. In addition, it was found that the estimation error in the scattering coefficient was reduced for smaller entrance port diameters. Therefore, when attempting to determine the scattering coefficient for strongly absorbing samples, it is necessary to consider both the angular distribution of the diffusely reflected light and the optimal entrance port diameter.
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Ishii K, Shibataf A, Oka K. Recess physical activity and perceived school environment among elementary school children. J Sci Med Sport 2014. [DOI: 10.1016/j.jsams.2014.11.360] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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78
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Oka K, Ishii K, Shibata A. Descriptive epidemiology of objectively measured sedentary time among Japanese adults. J Sci Med Sport 2014. [DOI: 10.1016/j.jsams.2014.11.379] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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79
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Ishii K, Narimatsu A, Adachi K. Review of Patient-Reported Outcomes in Diabetic Macular Edema. VALUE IN HEALTH : THE JOURNAL OF THE INTERNATIONAL SOCIETY FOR PHARMACOECONOMICS AND OUTCOMES RESEARCH 2014; 17:A575. [PMID: 27201932 DOI: 10.1016/j.jval.2014.08.1932] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
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Shinohara K, Ishii K, Ochiai K, Baba M, Sukegawa A, Sasao M, Kitajima S. Evaluation of two-stage system for neutron measurement aiming at increase in count rate at Japan Atomic Energy Agency-Fusion Neutronics Source. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2014; 85:11E823. [PMID: 25430388 DOI: 10.1063/1.4893941] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
In order to increase the count rate capability of a neutron detection system as a whole, we propose a multi-stage neutron detection system. Experiments to test the effectiveness of this concept were carried out on Fusion Neutronics Source. Comparing four configurations of alignment, it was found that the influence of an anterior stage on a posterior stage was negligible for the pulse height distribution. The two-stage system using 25 mm thickness scintillator was about 1.65 times the count rate capability of a single detector system for d-D neutrons and was about 1.8 times the count rate capability for d-T neutrons. The results suggested that the concept of a multi-stage detection system will work in practice.
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Nagoshi M, Makiishi N, Hamada E, Kawano T, Ishii K, Okada S, Sato M. Crystal structure of oxide layers on Mo-added Fe-Cr Alloys studied by GIXS and XPS. SURF INTERFACE ANAL 2014. [DOI: 10.1002/sia.5435] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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82
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Nakamura M, Tobita K, Gulden W, Watanabe K, Someya Y, Tanigawa H, Sakamoto Y, Araki T, Matsumiya H, Ishii K, Utoh H, Takase H, Hayashi T, Satou A, Yonomoto T, Federici G, Okano K. Study of safety features and accident scenarios in a fusion DEMO reactor. FUSION ENGINEERING AND DESIGN 2014. [DOI: 10.1016/j.fusengdes.2014.04.062] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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83
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Fujioka C, Ishii K, Yamanaga T, Ogino R, Kishimoto S, Maehama T, Yamaguchi T, Katayama S, Kawamorita R, Tada T, Nakajima T, Nishimura Y. Optimal Bladder Volume at Treatment Planning for Prostate Cancer Patients Receiving Volumetric Modulated Arc Therapy. Int J Radiat Oncol Biol Phys 2014. [DOI: 10.1016/j.ijrobp.2014.05.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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84
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Mabuchi A, Ishii K, Yamamoto R, Taguchi T, Murata M, Hayashi S, Mitsuda N. Clinical characteristics of monochorionic twins with large hemoglobin level discordance at birth. ULTRASOUND IN OBSTETRICS & GYNECOLOGY : THE OFFICIAL JOURNAL OF THE INTERNATIONAL SOCIETY OF ULTRASOUND IN OBSTETRICS AND GYNECOLOGY 2014; 44:311-315. [PMID: 24585685 DOI: 10.1002/uog.13343] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/11/2013] [Revised: 02/02/2014] [Accepted: 02/14/2014] [Indexed: 06/03/2023]
Abstract
OBJECTIVES To evaluate neonatal outcomes and clinical characteristics of monochorionic diamniotic (MCDA) twins with a large intertwin hemoglobin (Hb) difference at birth. METHODS This was a retrospective cohort study of MCDA twin gestations delivered at Osaka Medical Center and Research Institute for Maternal and Child Health between 2003 and 2012. Cases of pregnancy termination, acardiac twins or intrauterine death were excluded. A large intertwin Hb difference at birth was defined as > 8.0 g/dL according to the postnatal criteria for twin anemia-polycythemia sequence (TAPS). The intertwin reticulocyte count ratio (RCR) was calculated by dividing the reticulocyte count of the anemic twin by that of the polycythemic twin. Cases with Hb differences were divided into two groups according to the RCR, TAPS when the RCR was > 1.7 and acute fetofetal hemorrhage (AFFH) when the RCR was ≤ 1.7. Neonatal outcomes were compared between the TAPS and AFFH groups. RESULTS During the study period, 432 MCDA twin pregnancies of a total of 532 born at our hospital were analyzed. There were 12 (2.8%) cases of a large intertwin Hb difference. The median gestational age at birth of these cases was 34 (range, 23-38) weeks, and all were delivered by Cesarean section. There were seven (1.6%) cases of TAPS and five (1.2%) of AFFH. The neonatal survival rate was 91.7%; in one pair of twins with TAPS neonatal death occurred. All (100%) cases with TAPS and two (40%) with AFFH required blood transfusion or partial-exchange transfusion for at least one infant. CONCLUSIONS Although the incidence of TAPS and AFFH may be low in MCDA twins, many affected neonates required treatment for hematological abnormalities. Delivery of MCDA twins via Cesarean section does not appear to prevent AFFH, despite the absence of labor.
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Sakurai R, Fujiwara Y, Yasunaga M, Takeuchi R, Murayama Y, Ohba H, Sakuma N, Suzuki H, Oda K, Sakata M, Toyohara J, Ishiwata K, Shinkai S, Ishii K. Regional Cerebral Glucose Metabolism and Gait Speed in Healthy Community-Dwelling Older Women. J Gerontol A Biol Sci Med Sci 2014; 69:1519-27. [DOI: 10.1093/gerona/glu093] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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86
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Mochida Y, Ishii K, Yamada Y, Mitsugi N, Saito T. AB0368 Analyses for Recurrences of Hallux Valgus Deformity after Implant Surgery in Rheumatoid Arthritis. Ann Rheum Dis 2014. [DOI: 10.1136/annrheumdis-2014-eular.1090] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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87
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Ishii K, Mochida Y, Yamada Y, Mitsugi N, Saito T. AB0335 Investigation of the Association between Gastroesophageal Reflux Disease and Clinical Factors in Patients with Rheumatoid Arthritis. Ann Rheum Dis 2014. [DOI: 10.1136/annrheumdis-2014-eular.1981] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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88
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Ishii K, Fujita M, Sasaki T, Minola M, Dellea G, Mazzoli C, Kummer K, Ghiringhelli G, Braicovich L, Tohyama T, Tsutsumi K, Sato K, Kajimoto R, Ikeuchi K, Yamada K, Yoshida M, Kurooka M, Mizuki J. High-energy spin and charge excitations in electron-doped copper oxide superconductors. Nat Commun 2014; 5:3714. [PMID: 24762677 DOI: 10.1038/ncomms4714] [Citation(s) in RCA: 84] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2013] [Accepted: 03/24/2014] [Indexed: 11/09/2022] Open
Abstract
The evolution of electronic (spin and charge) excitations upon carrier doping is an extremely important issue in superconducting layered cuprates and the knowledge of its asymmetry between electron- and hole-dopings is still fragmentary. Here we combine X-ray and neutron inelastic scattering measurements to track the doping dependence of both spin and charge excitations in electron-doped materials. Copper L3 resonant inelastic X-ray scattering spectra show that magnetic excitations shift to higher energy upon doping. Their dispersion becomes steeper near the magnetic zone centre and they deeply mix with charge excitations, indicating that electrons acquire a highly itinerant character in the doped metallic state. Moreover, above the magnetic excitations, an additional dispersing feature is observed near the Γ-point, and we ascribe it to particle-hole charge excitations. These properties are in stark contrast with the more localized spin excitations (paramagnons) recently observed in hole-doped compounds even at high doping levels.
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Kakinuma H, Ishii K, Ishihama H, Honda M, Toyama Y, Matsumoto M, Aizawa M. Antibacterial polyetheretherketone implants immobilized with silver ions based on chelate-bonding ability of inositol phosphate: processing, material characterization, cytotoxicity, and antibacterial properties. J Biomed Mater Res A 2014; 103:57-64. [PMID: 24616120 DOI: 10.1002/jbm.a.35157] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2014] [Revised: 02/20/2014] [Accepted: 02/24/2014] [Indexed: 11/11/2022]
Abstract
We developed a novel antibacterial implant by forming a hydroxyapatite (HAp) film on polyetheretherketone (PEEK) substrate, and then immobilizing silver ions (Ag(+) ) on the HAp film based on the chelate-bonding ability of inositol phosphate (IP6). First, the PEEK surface was modified by immersion into concentrated sulfuric acid for 10 min. HAp film was formed on the acid-treated PEEK via the soft-solution process using simulated body fluid (SBF), urea, and urease. After HAp coating, specimens were immersed into IP6 solution, and followed by immersion into silver nitrite solution at concentrations of 0, 0.5, 1, 5 or 10 mM. Ag(+) ions were immobilized on the resulting HAp film due to the chelate-bonding ability of IP6. On cell-culture tests under indirect conditions by Transwell, MC3T3-E1 cells on the specimens derived from the 0.5 and 1 mM Ag(+) solutions showed high relative growth when compared with controls. Furthermore, on evaluation of antibacterial activity in halo test, elution of Ag(+) ions from Ag(+) -immobilized HAp film inhibited bacterial growth. Therefore, the above-mentioned results demonstrated that specimens had both biocompatibility and strong antibacterial activity. The present coating therefore provides bone bonding ability to the implant surface and prevents the formation of biofilms in the early postoperative period.
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Okamoto A, Oku T, Koike S, Sato Y, Ishii K, Kitajima S. Development of in situ energetic ion injector for magnetically confined plasmas using hydrogen storage electrode. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2014; 85:02B302. [PMID: 24593579 DOI: 10.1063/1.4825162] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
To develop a compact ion injector made of hydrogen storage material, we investigate a plasma response for a positively biased hydrogen storage electrode in a small standard heliac device. When the bias voltage of the electrode increases, a positive potential between the electrode and the space potential on the magnetic surface emerges. The emission of hydrogen atom line also increases. To clarify the origin of the increase in emission, we designed an imaging system with sufficient temporal resolution.
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Suzuki Y, Kiyosawa M, Wakakura M, Mochizuki M, Ishiwata K, Oda K, Ishii K. Glucose hypermetabolism in the thalamus of patients with drug-induced blepharospasm. Neuroscience 2014; 263:240-9. [PMID: 24462606 DOI: 10.1016/j.neuroscience.2014.01.024] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2013] [Revised: 01/13/2014] [Accepted: 01/14/2014] [Indexed: 12/26/2022]
Abstract
We examined the difference in cerebral function alterations between drug-induced blepharospasm patients and essential blepharospasm (EB) patients by using positron emission tomography with (18)F-fluorodeoxyglucose. Cerebral glucose metabolism was examined in 21 patients with drug-induced blepharospasm (5 men and 16 women; mean age, 53.1 [range, 29-78] years), 21 essential EB patients (5 men and 16 women; mean age, 53.0 [range, 33-72] years) and 24 healthy subjects (6 men and 18 women; mean age, 57.9 [range, 22-78] years) with long-term history of benzodiazepines use (drug healthy subjects). Drug-induced blepharospasm patients developed symptoms while taking benzodiazepines or thienodiazepines. Sixty-three normal volunteers (15 men and 48 women; mean age, 53.6 [range, 20-70] years) were examined as controls. Differences between the patient groups and control group were examined by statistical parametric mapping. Additionally, we defined regions of interests on both sides of the thalamus, caudate nucleus, anterior putamen, posterior putamen and primary somatosensory area. The differences between groups were tested using two-sample t-tests with Bonferroni correction for multiple comparisons. Cerebral glucose hypermetabolism on both side of the thalamus was detected in drug-induced blepharospasm, EB patients and drug healthy subjects by statistical parametric mapping. In the analysis of regions of interest, glucose metabolism in both sides of the thalamus in the drug-induced blepharospasm group was significantly lower than that in the EB group. Moreover, we observed glucose hypermetabolism in the anterior and posterior putamen bilaterally in EB group but not in drug-induced blepharospasm group and drug healthy subjects. Long-term regimens of benzodiazepines or thienodiazepines may cause down-regulation of benzodiazepine receptors in the brain. We suggest that the functional brain alteration in drug-induced blepharospasm patients is similar to that in EB patients, and that alteration of the GABAergic system might be related to the pathology of both blepharospasm types.
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Ogino R, Ishii K, Kishimoto S, Ichioka K, Nakahara R, Okada W, Kawamorita R, Nakajima T. EP-1334: A dose-volume intercomparison of VMAT and 3D-CRT for salvage radiation therapy after prostatectomy. Radiother Oncol 2014. [DOI: 10.1016/s0167-8140(15)31452-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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93
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Saito N, Shime N, Sugiyama K, Yasuda H, Ishii K, Masuda Y, Kanemura T, Sakamoto W, Hirayu T. Validation of the 2005 American Thoracic Society/Infectious Diseases Society of America guidelines for ventilator-associated pneumonia: a Japanese multicenter observational study. Crit Care 2014. [PMCID: PMC4069581 DOI: 10.1186/cc13495] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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94
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Ishii K, Kurasawa K, Tanabe S, Noguchi T. Complementary cooperation of an ambulance helicopter and car with medical doctors: meaning of simultaneous dispatch. Crit Care 2014. [PMCID: PMC4068871 DOI: 10.1186/cc13260] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
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95
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Maie K, Okoshi Y, Takaiwa N, Kurita N, Hasegawa Y, Homma M, Ishii K, Kohda Y, Chiba S. Aprepitant does not alter prednisolone pharmacokinetics in patients treated with R-CHOP. Ann Oncol 2014; 25:298-9. [DOI: 10.1093/annonc/mdt477] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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Takahashi H, Ishii K, Hosokawa C, Hyodo T, Kashiwagi N, Matsuki M, Ashikaga R, Murakami T. Clinical application of 3D arterial spin-labeled brain perfusion imaging for Alzheimer disease: comparison with brain perfusion SPECT. AJNR Am J Neuroradiol 2013; 35:906-11. [PMID: 24263694 DOI: 10.3174/ajnr.a3780] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE Alzheimer disease is the most common neurodegenerative disorder with dementia, and a practical and economic biomarker for diagnosis of Alzheimer disease is needed. Three-dimensional arterial spin-labeling, with its high signal-to-noise ratio, enables measurement of cerebral blood flow precisely without any extrinsic tracers. We evaluated the performance of 3D arterial spin-labeling compared with SPECT, and demonstrated the 3D arterial spin-labeled imaging characteristics in the diagnosis of Alzheimer disease. MATERIALS AND METHODS This study included 68 patients with clinically suspected Alzheimer disease who underwent both 3D arterial spin-labeling and SPECT imaging. Two readers independently assessed both images. Kendall W coefficients of concordance (K) were computed, and receiver operating characteristic analyses were performed for each reader. The differences between the images in regional perfusion distribution were evaluated by means of statistical parametric mapping, and the incidence of hypoperfusion of the cerebral watershed area, referred to as "borderzone sign" in the 3D arterial spin-labeled images, was determined. RESULTS Readers showed K = 0.82/0.73 for SPECT/3D arterial spin-labeled imaging, and the respective areas under the receiver operating characteristic curve were 0.82/0.69 for reader 1 and 0.80/0.69 for reader 2. Statistical parametric mapping showed that the perisylvian and medial parieto-occipital perfusion in the arterial spin-labeled images was significantly higher than that in the SPECT images. Borderzone sign was observed on 3D arterial spin-labeling in 70% of patients misdiagnosed with Alzheimer disease. CONCLUSIONS The diagnostic performance of 3D arterial spin-labeling and SPECT for Alzheimer disease was almost equivalent. Three-dimensional arterial spin-labeled imaging was more influenced by hemodynamic factors than was SPECT imaging.
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Tsuruoka N, Ishii K, Matsunaga T, Nagatomi R, Haga Y. Measurement of subcutaneous biological substances using thin metal needle with micro flow channel. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2013; 2013:4478-81. [PMID: 24110728 DOI: 10.1109/embc.2013.6610541] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Concentrations of biological substances are useful as indicators of physiological and pathological states. In order to monitor biological substances in daily life, we developed a minimally invasive needle type device with which biological substances are extracted through a microperfusion system inserted under the skin. The perfusion needle has a flow channel with perforated membrane through which biological substances from subepidermal tissue are extracted. The efficacy of the device was examined by measuring lactate concentration of exercising mice. Lactate was successfully collected from the back skin of the mice running on a treadmill using a fabricated microperfusion needle. Lactate concentration of perfused solution correlated with blood lactate concentration.
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Ishii K, Ogino R, Hosokawa Y, Fujioka C, Nakahara R, Okada W, Kawamorita R, Hayashi Y, Nakajima T. A Treatment Planning and Acute Toxicity of Volumetric Modulated Arc Therapy (VMAT) in the Treatment of High-Risk Prostate Cancer With Whole Pelvic Radiation Therapy. Int J Radiat Oncol Biol Phys 2013. [DOI: 10.1016/j.ijrobp.2013.06.946] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Ishii K, Ogino R, Okada W, Nakahara R, Kawamorita R, Nakajima T. A dosimetric comparison of RapidArc and IMRT with hypofractionated simultaneous integrated boost to the prostate for treatment of prostate cancer. Br J Radiol 2013; 86:20130199. [PMID: 23995872 DOI: 10.1259/bjr.20130199] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
OBJECTIVE To compare the dosimetric results and treatment delivery efficiency among RapidArc® (Varian Medical Systems, Palo Alto, CA), 7-field intensity-modulated radiotherapy (7-f IMRT) and 9-field IMRT (9-f IMRT) with hypofractionated simultaneous integrated boost to the prostate. METHODS RapidArc, 7-f IMRT and 9-f IMRT plans were created for 21 consecutive patients treated for high-risk prostate cancer using the Eclipse™ treatment planning system (Varian Medical Systems). All plans were designed to deliver 70.0 Gy in 28 fractions to the prostate planning target volume (PTV) while simultaneously delivering 50.4 Gy in 28 fractions to the pelvic nodal PTV. Target coverage and sparing of organs at risk (OARs) were compared across techniques. The total number of monitor units (MUs) and the treatment time were used to assess treatment delivery efficiency. RESULTS RapidArc resulted in slightly superior conformity and homogeneity of prostate PTV, whereas all plans were comparable with respect to dose to the nodal PTV. Although OARs sparing for RapidArc and 7-f IMRT plans were almost equivalent, 9-f IMRT achieved better sparing of the rectum and bladder than RapidArc and 7-f IMRT. RapidArc provided the highest treatment delivery efficiency with the lowest MUs and shortest treatment time. CONCLUSION RapidArc resulted in similar OAR sparing to 7-f IMRT, whereas 9-f IMRT provided the best OAR sparing. Treatment delivery efficiency is significantly higher for RapidArc. ADVANCES IN KNOWLEDGE This study validated the feasibility and limitations of RapidArc in the treatment of high-risk prostate cancer with complex pelvic target volumes.
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Abstract
There is increasing use of neuroimaging modalities, including PET, for diagnosing dementia. For example, FDG-PET demonstrates hypometabolic regions in the posterior cingulate gyri, precuneus, and parietotemporal association cortices, while amyloid PET indicates amyloid deposition in Alzheimer disease and mild cognitive impairment due to Alzheimer disease. Furthermore, the use of combination PET with structural MR imaging can improve the diagnostic accuracy of dementia. In other neurodegenerative dementias, each disease exhibits a specific metabolic reduction pattern. In dementia with Lewy bodies, occipital glucose metabolism is decreased, while in frontotemporal dementia, frontal and anterior temporal metabolism is predominantly decreased. These FDG-PET findings and positive or negative amyloid deposits are important biomarkers for various neurodegenerative dementias.
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