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Helmer KG, Chou MC, Preciado RI, Gimi B, Rollins NK, Song A, Turner J, Mori S. Multi-site study of diffusion metric variability: effects of site, vendor, field strength, and echo time on regions-of-interest and histogram-bin analyses. PROCEEDINGS OF SPIE--THE INTERNATIONAL SOCIETY FOR OPTICAL ENGINEERING 2016; 9788. [PMID: 27330240 DOI: 10.1117/12.2217445] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
It is now common for magnetic-resonance-imaging (MRI) based multi-site trials to include diffusion-weighted imaging (DWI) as part of the protocol. It is also common for these sites to possess MR scanners of different manufacturers, different software and hardware, and different software licenses. These differences mean that scanners may not be able to acquire data with the same number of gradient amplitude values and number of available gradient directions. Variability can also occur in achievable b-values and minimum echo times. The challenge of a multi-site study then, is to create a common protocol by understanding and then minimizing the effects of scanner variability and identifying reliable and accurate diffusion metrics. This study describes the effect of site, scanner vendor, field strength, and TE on two diffusion metrics: the first moment of the diffusion tensor field (mean diffusivity, MD), and the fractional anisotropy (FA) using two common analyses (region-of-interest and mean-bin value of whole brain histograms). The goal of the study was to identify sources of variability in diffusion-sensitized imaging and their influence on commonly reported metrics. The results demonstrate that the site, vendor, field strength, and echo time all contribute to variability in FA and MD, though to different extent. We conclude that characterization of the variability of DTI metrics due to site, vendor, field strength, and echo time is a worthwhile step in the construction of multi-center trials.
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Helmer KG, Chou MC, Preciado RI, Gimi B, Rollins NK, Song A, Turner J, Mori S. Multi-site Study of Diffusion Metric Variability: Characterizing the Effects of Site, Vendor, Field Strength, and Echo Time using the Histogram Distance. PROCEEDINGS OF SPIE--THE INTERNATIONAL SOCIETY FOR OPTICAL ENGINEERING 2016; 9788. [PMID: 27350723 DOI: 10.1117/12.2217449] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
MRI-based multi-site trials now routinely include some form of diffusion-weighted imaging (DWI) in their protocol. These studies can include data originating from scanners built by different vendors, each with their own set of unique protocol restrictions, including restrictions on the number of available gradient directions, whether an externally-generated list of gradient directions can be used, and restrictions on the echo time (TE). One challenge of multi-site studies is to create a common imaging protocol that will result in a reliable and accurate set of diffusion metrics. The present study describes the effect of site, scanner vendor, field strength, and TE on two common metrics: the first moment of the diffusion tensor field (mean diffusivity, MD), and the fractional anisotropy (FA). We have shown in earlier work that ROI metrics and the mean of MD and FA histograms are not sufficiently sensitive for use in site characterization. Here we use the distance between whole brain histograms of FA and MD to investigate within- and between-site effects. We concluded that the variability of DTI metrics due to site, vendor, field strength, and echo time could influence the results in multi-center trials and that histogram distance is sensitive metrics for each of these variables.
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Zhao L, Wagner P, Barnsley JE, Clarke TM, Gordon KC, Mori S, Mozer AJ. Enhancement of dye regeneration kinetics in dichromophoric porphyrin-carbazole triphenylamine dyes influenced by more exposed radical cation orbitals. Chem Sci 2016; 7:3506-3516. [PMID: 29997843 PMCID: PMC6007200 DOI: 10.1039/c6sc00429f] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2016] [Accepted: 02/27/2016] [Indexed: 11/21/2022] Open
Abstract
Reduction kinetics of oxidized dyes absorbed on semiconductor surfaces and immersed in redox active electrolytes has been mainly modeled based on the free energy difference between the oxidation potential of the dye and the redox potential of the electrolyte. Only a few mechanisms have been demonstrated to enhance the kinetics by other means. In this work, the rate constant of the reduction of oxidized porphyrin dye is enhanced by attaching non-conjugated carbazole triphenylamine moiety using iodine/triiodide and tris(2,2'-bispyridinium)cobalt II/III electrolytes. These results are obtained using transient absorption spectroscopy by selectively probing the regeneration kinetics at the porphyrin radical cation and the carbazole triphenylamine radical cation absorption wavelengths. The enhancement in the reduction kinetics is not attributed to changes in the driving force, but to the more exposed dye cation radical orbitals of the dichromophoric dye. The results are important for the development of high efficiency photo-electrochemical devices with minimalized energy loss at electron transfer interfaces.
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Hashimoto K, Mori S, Oda Y, Nakano A, Sawamura T, Akagi M. Lectin-like oxidized low density lipoprotein receptor 1-deficient mice show resistance to instability-induced osteoarthritis. Scand J Rheumatol 2016; 45:412-22. [DOI: 10.3109/03009742.2015.1135979] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Mori S, Simkhada D, Zhang H, Erb MS, Zhang Y, Williams H, Fedoseyenko D, Russell WK, Kim D, Fleer N, Ealick SE, Watanabe CMH. Polyketide Ring Expansion Mediated by a Thioesterase, Chain Elongation and Cyclization Domain, in Azinomycin Biosynthesis: Characterization of AziB and AziG. Biochemistry 2016; 55:704-14. [PMID: 26731610 PMCID: PMC4738070 DOI: 10.1021/acs.biochem.5b01050] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
The azinomycins are a family of potent antitumor agents with the ability to form interstrand cross-links with DNA. This study reports on the unusual biosynthetic formation of the 5-methyl naphthoate moiety, which is essential for effective DNA association. While sequence analysis predicts that the polyketide synthase (AziB) catalyzes the formation of this naphthoate, 2-methylbenzoic acid, a truncated single-ring product, is formed instead. We demonstrate that the thioesterase (AziG) acts as a chain elongation and cyclization (CEC) domain and is required for the additional two rounds of chain extension to form the expected product.
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Murakami TN, Koumura N, Yoshida E, Funaki T, Takano S, Kimura M, Mori S. An Alkyloxyphenyl Group as a Sterically Hindered Substituent on a Triphenylamine Donor Dye for Effective Recombination Inhibition in Dye-Sensitized Solar Cells. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2016; 32:1178-1183. [PMID: 26672394 DOI: 10.1021/acs.langmuir.5b04127] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Recombination reactions in dye-sensitized solar cells (DSSCs) may substantially decrease the open-circuit voltage (Voc) with cobalt complex redox electrolyte. Managing steric hindrance in the dye structure is necessary to inhibit recombination reactions and thereby increase the Voc and achieve high power-conversion efficiency (PCE). New dyes with large-sized donors based on triphenylamine and modified with 4-(hexyloxy)phenyl groups were developed to identify an effective inhibitor for the recombination reaction in DSSCs with a cobalt complex redox electrolyte. The 4-(hexyloxy)phenyl tetra-adducts dye MK-123 effectively inhibited the recombination reaction, and the DSSC fabricated using this dye exhibited the highest Voc (greater than 900 mV) among the cells with the investigated dyes. However, the short-circuit current (Jsc) of the MK-123 cell was lower than that of the cell with the simple triphenylamine donor dye, MK-89. In contrast, the cell with bis-adducts dye MK-136 also exhibited an increase in its Voc without a decrease in its Jsc. Among the investigated dyes, MK-136 exhibited the highest PCE of 8.9%. The effects of the steric hindrance of the 4-(hexyloxy)phenyl substituent are discussed.
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Morihiro K, Hasegawa O, Mori S, Tsunoda S, Obika S. C5-azobenzene-functionalized locked nucleic acid uridine: isomerization properties, hybridization ability, and enzymatic stability. Org Biomol Chem 2016; 13:5209-14. [PMID: 25853508 DOI: 10.1039/c5ob00477b] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Oligonucleotides (ONs) modified with a locked nucleic acid (LNA) are widely used in the fields of therapeutics, diagnosis, and nanotechnology. There have been significant efforts towards developing LNA analogues bearing modified bridges to improve their hybridization ability, nuclease resistance, and pharmacokinetic profiles. Moreover, nucleobase modifications of LNA are useful strategies for the functionalization of ONs. Modifications of the C5-position of pyrimidine nucleobases are particularly interesting because they enable predictable positioning of functional groups in the major groove of the duplex. Here we report the synthesis of C5-azobenzene-functionalized LNA uridine (LNA-U(Az)) and properties of LNA-U(Az)-modified ONs, including isomerization properties, hybridization ability, and enzyme stability. LNA-U(Az) in ON is photo-isomerized effectively and reversibly by irradiation at 365 nm (trans to cis) and 450 nm (cis to trans). LNA-U(Az)-modified ONs show RNA-selective hybridization ability despite the large hydrophobic azobenzene moiety extending into the major groove of the duplex. The enzymatic stability of LNA-U(Az)-modified ONs is higher than that of natural and LNA-modified ONs with or without photo-irradiation. Our results indicate that LNA-U(Az) holds promise for RNA targeting and photo-switchable technologies.
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Kotani A, Nakajima H, Harada K, Ishii Y, Mori S. B12-O-09Lorentz TEM observation of magnetic bubbles in manganites. Microscopy (Oxf) 2015. [DOI: 10.1093/jmicro/dfv096] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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109
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Kurushima K, Cheong SW, Mori S. B23-P-11Charged Walls in Hybrid Improper Ferroelectric (Ca,Sr) 3Ti 2O 7Revealed by Scanning/Transmission Electron Microscopy(S/TEM). Microscopy (Oxf) 2015. [DOI: 10.1093/jmicro/dfv285] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Mori S, Tsukasaki H, Ishii Y, Kurushima K. B23-O-08Microstructures in improper ferroelectric compounds revealed by electron microscopy. Microscopy (Oxf) 2015. [DOI: 10.1093/jmicro/dfv166] [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] Open
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Mori S, Williams H, Cagle D, Karanovich K, Horgen FD, Smith R, Watanabe CMH. Macrolactone Nuiapolide, Isolated from a Hawaiian Marine Cyanobacterium, Exhibits Anti-Chemotactic Activity. Mar Drugs 2015; 13:6274-90. [PMID: 26473885 PMCID: PMC4626689 DOI: 10.3390/md13106274] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2015] [Revised: 09/25/2015] [Accepted: 09/25/2015] [Indexed: 12/21/2022] Open
Abstract
A new bioactive macrolactone, nuiapolide (1) was identified from a marine cyanobacterium collected off the coast of Niihau, near Lehua Rock. The natural product exhibits anti-chemotactic activity at concentrations as low as 1.3 μM against Jurkat cells, cancerous T lymphocytes, and induces a G2/M phase cell cycle shift. Structural characterization of the natural product revealed the compound to be a 40-membered macrolactone with nine hydroxyl functional groups and a rare tert-butyl carbinol residue.
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Zhao L, Wagner P, van der Salm H, Gordon KC, Mori S, Mozer AJ. Enhanced Electron Lifetimes in Dye-Sensitized Solar Cells Using a Dichromophoric Porphyrin: The Utility of Intermolecular Forces. ACS APPLIED MATERIALS & INTERFACES 2015; 7:22078-83. [PMID: 26375165 DOI: 10.1021/acsami.5b07361] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Electron lifetimes in dye-sensitized solar cells employing a porphyrin dye, an organic dye, a 1:1 mixture of the two dyes, and a dichromophoric dye design consisting of the two dyes using a nonconjugated linker were measured, suggesting that the dispersion force of the organic dyes has a significant detrimental effect on the electron lifetime and that the dichromophoric design can be utilized to control the effect of the dispersion force.
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Ikeuchi T, Agrawal S, Ezoe M, Mori S, Kimura M. Enhanced Charge Separation Efficiency in Pyridine-Anchored Phthalocyanine-Sensitized Solar Cells by Linker Elongation. Chem Asian J 2015. [DOI: 10.1002/asia.201500756] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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Fukumoto K, Taniguchi T, Kawaguchi K, Fukui T, Ishiguro F, Nakamura S, Mori S, Yokoi K. P-205USE OF 18F-FDG POSITRON EMISSION TOMOGRAPHY/COMPUTED TOMOGRAPHY IN PATIENTS WITH INVASIVE THYMIC EPITHELIAL TUMOURS WHO UNDERWENT INDUCTION THERAPIES. Interact Cardiovasc Thorac Surg 2015. [DOI: 10.1093/icvts/ivv204.205] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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115
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Yamamoto S, Mori S, Wagner P, Mozer AJ, Kimura M. A Novel Covalently Linked Zn Phthalocyanine-Zn Porphyrin Dyad for Dye-sensitized Solar Cells. Isr J Chem 2015. [DOI: 10.1002/ijch.201500023] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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116
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Mori S, Inaniwa T, Miki K, Tanimoto K, Tajiri M, Kuroiwa D, Nakao M, Shiraishi Y, Shibayama K, Tsuji H. Variation in patient position and impact on carbon-ion scanning beam distribution during prostate treatment. Br J Radiol 2015; 88:20140623. [PMID: 25950822 DOI: 10.1259/bjr.20140623] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
OBJECTIVE We assessed the impact of changes in patient position on carbon-ion scanning beam distribution during treatment for prostate cancer. METHODS 68 patients were selected. Carbon-ion scanning dose was calculated. Two different planning target volumes (PTVs) were defined: PTV1 was the clinical target volume plus a set-up margin for the anterior/lateral sides and posterior side, while PTV2 was the same as PTV1 minus the posterior side. Total prescribed doses of 34.4 Gy [relative biological effectiveness (RBE)] and 17.2 Gy (RBE) were given to PTV1 and PTV2, respectively. To estimate the influence of geometric variations on dose distribution, the dose was recalculated on the rigidly shifted single planning CT based on two dimensional-three dimensional rigid registration of the orthogonal radiographs before and after treatment for the fraction of maximum positional changes. RESULTS Intrafractional patient positional change values averaged over all patients throughout the treatment course were less than the target registration error = 2.00 mm and angular error = 1.27°. However, these maximum positional errors did not occur in all 12 treatment fractions. Even though large positional changes occurred during irradiation in all treatment fractions, lowest dose encompassing 95% of the target (D95)-PTV1 was >98% of the prescribed dose. CONCLUSION Intrafractional patient positional changes occurred during treatment beam irradiation and degraded carbon-ion beam dose distribution. Our evaluation did not consider non-rigid deformations, however, dose distribution was still within clinically acceptable levels. ADVANCES IN KNOWLEDGE Inter- and intrafractional changes did not affect carbon-ion beam prostate treatment accuracy.
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Arita N, Ushio Y, Hayakawa T, Mori S, Bitoh S, Hasegawa H, Akagi K, Kano M, Oku Y, Go J. Role of tumor markers in the management of primary intracranial germ cell tumors. PROGRESS IN EXPERIMENTAL TUMOR RESEARCH 2015; 30:289-95. [PMID: 2442797 DOI: 10.1159/000413686] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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Miow QH, Tan TZ, Ye J, Lau JA, Yokomizo T, Thiery JP, Mori S. Epithelial-mesenchymal status renders differential responses to cisplatin in ovarian cancer. Oncogene 2015. [PMID: 24858042 DOI: 10.1038/onc.2014.136] [] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Chemoresistance to platinums, such as cisplatin, is of critical concern in the treatment of ovarian cancer. Recent evidence has linked epithelial-mesenchymal transition (EMT) as a contributing mechanism. The current study explored the connection between cellular responses to cisplatin and EMT in ovarian cancer. Expression microarrays were utilized to estimate the EMT status as a binary phenotype, and the transcriptional responses of 46 ovarian cancer cell lines to cisplatin were measured at dosages equivalent to 50% growth inhibition. Phenotypic responses to cisplatin were quantified with respect to cell number, proliferation rate and apoptosis, and then compared with the epithelial or mesenchymal status. Ovarian cancer cell lines with an epithelial status exhibited higher resistance to cisplatin treatment in the MTS assay than those with a mesenchymal status. Pathway analyses revealed the induction of G1/S- and S-phase genes (P=0.001) and the activation of multiple NF-κB (nuclear factor kappa-light-chain-enhancer of activated B cells) downstream genes (P=0.0016) by cisplatin selectively in epithelial-like cell lines. BrdU incorporation and Caspase-3/7 release assays confirmed impaired apoptosis in epithelial-like ovarian cancer cells. In clinical samples, we observed resistance to single platinum treatment and the selective activation of the NF-κB pathway by platinum in ovarian cancers with an epithelial status. Overall, our results suggest that, in epithelial-like ovarian cancer cells, NF-κB activation by cisplatin may lead to defective apoptosis, preferential proliferation arrest and a consequential decreased sensitivity to cisplatin.
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Kumagai M, Mori S, Yamamoto N. Impact of treatment planning with deformable image registration on dose distribution for carbon-ion beam lung treatment using a fixed irradiation port and rotating couch. Br J Radiol 2015; 88:20140734. [PMID: 25811094 DOI: 10.1259/bjr.20140734] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
OBJECTIVE When using a fixed irradiation port, treatment couch rotation is necessary to increase beam angle selection. We evaluated dose variations associated with positional morphological changes to organs. METHODS We retrospectively chose the data sets of ten patients with lung cancer who underwent respiratory-gated CT at three different couch rotation angles (0°, 20° and -20°). The respective CT data sets are referred to as CT0, CT20 and CT-20. Three treatment plans were generated as follows: in Plan 1, all compensating bolus designs and dose distributions were calculated using CT0. To evaluate the rotation effect without considering morphology changes, in Plan 2, the compensating boli designed using CT0 were applied to the CT±20 images. Plan 3 involved compensating boli designed using the CT±20 images. The accumulated dose distributions were calculated using deformable image registration (DIR). RESULTS A sufficient prescribed dose was calculated for the planning target volume (PTV) in Plan 1 [minimum dose received by a volume ≥95% (D95) > 95.8%]. By contrast, Plan 2 showed degraded dose conformation to the PTV (D95 > 90%) owing to mismatch of the bolus design to the morphological positional changes in the respective CT. The dose assessment results of Plan 3 were very close to those of Plan 1. CONCLUSION Dose distribution is significantly affected by whether or not positional organ morphology changes are factored into dose planning. ADVANCES IN KNOWLEDGE In treatment planning using multiple CT scans with different couch positions, it is mandatory to calculate the accumulated dose using DIR.
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Kimura M, Tohata Y, Ikeuchi T, Mori S. Zinc phthalocyanine sensitizer having double carboxylic acid anchoring groups for dye-sensitized solar cells with cobalt(ii/iii)-based redox electrolyte. RSC Adv 2015. [DOI: 10.1039/c5ra16610a] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Double anchored ZnPc sensitizer PcS25 exhibited higher conversion efficiency in dye-sensitized solar cells with cobalt(ii/iii)-based redox electrolyte than single-anchored ZnPc sensitizers.
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Mori S, Amano S, Furukawa T, Shirai T, Noda K. Effect of secondary particles on image quality of dynamic flat panels in carbon ion scanning beam treatment. Br J Radiol 2014; 88:20140567. [PMID: 25536444 DOI: 10.1259/bjr.20140567] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
OBJECTIVE Real-time markerless tumour tracking using radiographic fluoroscopic imaging is one of the better solutions to improving respiratory-gated radiotherapy. However, particle beams cause secondary particles from patients, which could affect radiographs. Here, we evaluated the quality of radiographs during carbon ion pencil beam scanning (CPBS) irradiation for respiratory gating. METHODS A water phantom and chest phantom were used. The phantoms were irradiated with CPBS at 290 MeV n(-1) from orthogonal directions. Dose rates were 3.4 × 10(8), 1.14 × 10(8) and 3.79 × 10(7) particles per second. A dynamic flat panel detector (DFPD) was installed on the upstream (DFPD1) or downstream (DFPD2) side of the vertical irradiation port. DFPD images were acquired during CPBS at 15.00, 7.50 and 3.75 frames per second (fps). Charge on the DFPD was cleaned using fast readout technique every 30 fps. DFPD images were acquired during CPBS with radiographic exposure, and results with and without fast readout technique were compared. RESULTS Secondary particles were visualized as spots or streak-like shapes. Capture of secondary particles from the horizontal beam direction was lower with fast readout technique than without it. With regard to beam irradiation direction dependency, CPBS from the horizontal direction resulted in a greater magnitude of secondary particles reaching DFPD2 than reaching DFPD1. When CPBS was delivered from the vertical direction, however, the magnitude of secondary particles on both DFPDs was very similar. CONCLUSION Fast readout technique minimized the effect of secondary particles on DFPD images during CPBS. ADVANCES IN KNOWLEDGE This technique may be useful for markerless tumour tracking for respiratory gating.
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Ikeuchi T, Nomoto H, Masaki N, Griffith MJ, Mori S, Kimura M. Molecular engineering of zinc phthalocyanine sensitizers for efficient dye-sensitized solar cells. Chem Commun (Camb) 2014; 50:1941-3. [PMID: 24396860 DOI: 10.1039/c3cc47714b] [Citation(s) in RCA: 105] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Asymmetric zinc phthalocyanines with alkyl chain substituents formed highly efficient light-harvesting layers on a TiO2 surface. Dye-sensitized solar cells using PcS20 exhibited a record efficiency of 6.4% under one-sun irradiation.
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Mori S, Inaniwa T, Miki K, Shirai T, Noda K. Implementation of a target volume design function for intrafractional range variation in a particle beam treatment planning system. Br J Radiol 2014; 87:20140233. [PMID: 25168286 DOI: 10.1259/bjr.20140233] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
OBJECTIVE Treatment planning for charged particle therapy in the thoracic and abdominal regions should take account of range uncertainty due to intrafractional motion. Here, we developed a design tool (4Dtool) for the target volume [field-specific target volume (FTV)], which accounts for this uncertainty using four-dimensional CT (4DCT). METHODS Target and normal tissue contours were input manually into a treatment planning system (TPS). These data were transferred to the 4Dtool via the picture archiving and communication system (PACS). Contours at the reference phase were propagated to other phases by deformable image registration. FTV was calculated using 4DCT on the 4Dtool. The TPS displays FTV contours using digital imaging and communications in medicine files imported from the PACS. These treatment parameters on the CT image at the reference phase were then used for dose calculation on the TPS. The tool was tested in single clinical case randomly selected from patients treated at our centre for lung cancer. RESULTS In this clinical case, calculation of dose distribution with the 4Dtool resulted in the successful delivery of carbon-ion beam at the reference phase of 95% of the prescribed dose to the clinical target volume (CTV). Application to the other phases also provided sufficient dose to the CTV. CONCLUSION The 4Dtool software allows the design of the target volume with consideration to intrafractional range variation and is now in routine clinical use at our institution. ADVANCES IN KNOWLEDGE Our alternative technique represents a practical approach to four-dimensional treatment planning within the current state of charged particle therapy.
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Sato K, Ishigame K, Ying SH, Oishi K, Miller MI, Mori S. Macro- and microstructural changes in patients with spinocerebellar ataxia type 6: assessment of phylogenetic subdivisions of the cerebellum and the brain stem. AJNR Am J Neuroradiol 2014; 36:84-90. [PMID: 25169926 DOI: 10.3174/ajnr.a4085] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE Site-specific degeneration patterns of the infratentorial brain in relation to phylogenetic origins may relate to symptoms in patients with spinocerebellar degeneration, but the patterns are still unclear. We investigated macro- and microstructural changes of the infratentorial brain based on phylogenetic origins and their correlation with symptoms in patients with spinocerebellar ataxia type 6. MATERIALS AND METHODS MR images of 9 patients with spinocerebellar ataxia type 6 and 9 age- and sex-matched controls were obtained. We divided the infratentorial brain on the basis of phylogenetic origins and performed an atlas-based analysis. Comparisons of the 2 groups and a correlation analysis assessed with the International Cooperative Ataxia Rating Scale excluding age effects were performed. RESULTS A significant decrease of fractional volume and an increase of mean diffusivity were seen in all subdivisions of the cerebellum and in all the cerebellar peduncles except mean diffusivity in the inferior cerebellar peduncle in patients compared with controls (P < .0001 to <.05). The bilateral anterior lobes showed the strongest atrophy. Fractional volume decreased mainly in old regions, whereas mean diffusivity increased mainly in new regions of the cerebellum. Reflecting this tendency, the International Cooperative Ataxia Rating Scale total score showed strong correlations in fractional volume in the right flocculonodular lobe and the bilateral deep structures and in mean diffusivity in the bilateral posterior lobes (r = 0.73 to ±0.87). CONCLUSIONS We found characteristic macro- and microstructural changes, depending on phylogenetic regions of the infratentorial brain, that strongly correlated with clinical symptoms in patients with spinocerebellar ataxia type 6.
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Mori S, Ito A, Sato S, Ako K, Tada E, Shibanuma K, Hattori Y, Iida H. Dose Rate Analyses around the Equatorial and Divertor Ports during ITER In-Vessel Components Maintenance. J NUCL SCI TECHNOL 2014. [DOI: 10.1080/00223131.2000.10874884] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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