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Nagayama Y, Emoto T, Kato Y, Kidoh M, Oda S, Sakabe D, Funama Y, Nakaura T, Hayashi H, Takada S, Uchimura R, Hatemura M, Tsujita K, Hirai T. Improving image quality with super-resolution deep-learning-based reconstruction in coronary CT angiography. Eur Radiol 2023; 33:8488-8500. [PMID: 37432405 DOI: 10.1007/s00330-023-09888-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2022] [Revised: 03/22/2023] [Accepted: 04/23/2023] [Indexed: 07/12/2023]
Abstract
OBJECTIVES To evaluate the effect of super-resolution deep-learning-based reconstruction (SR-DLR) on the image quality of coronary CT angiography (CCTA). METHODS Forty-one patients who underwent CCTA using a 320-row scanner were retrospectively included. Images were reconstructed with hybrid (HIR), model-based iterative reconstruction (MBIR), normal-resolution deep-learning-based reconstruction (NR-DLR), and SR-DLR algorithms. For each image series, image noise, and contrast-to-noise ratio (CNR) at the left main trunk, right coronary artery, left anterior descending artery, and left circumflex artery were quantified. Blooming artifacts from calcified plaques were measured. Image sharpness, noise magnitude, noise texture, edge smoothness, overall quality, and delineation of the coronary wall, calcified and noncalcified plaques, cardiac muscle, and valves were subjectively ranked on a 4-point scale (1, worst; 4, best). The quantitative parameters and subjective scores were compared among the four reconstructions. Task-based image quality was assessed with a physical evaluation phantom. The detectability index for the objects simulating the coronary lumen, calcified plaques, and noncalcified plaques was calculated from the noise power spectrum (NPS) and task-based transfer function (TTF). RESULTS SR-DLR yielded significantly lower image noise and blooming artifacts with higher CNR than HIR, MBIR, and NR-DLR (all p < 0.001). The best subjective scores for all the evaluation criteria were attained with SR-DLR, with significant differences from all other reconstructions (p < 0.001). In the phantom study, SR-DLR provided the highest NPS average frequency, TTF50%, and detectability for all task objects. CONCLUSION SR-DLR considerably improved the subjective and objective image qualities and object detectability of CCTA relative to HIR, MBIR, and NR-DLR algorithms. CLINICAL RELEVANCE STATEMENT The novel SR-DLR algorithm has the potential to facilitate accurate assessment of coronary artery disease on CCTA by providing excellent image quality in terms of spatial resolution, noise characteristics, and object detectability. KEY POINTS • SR-DLR designed for CCTA improved image sharpness, noise property, and delineation of cardiac structures with reduced blooming artifacts from calcified plaques relative to HIR, MBIR, and NR-DLR. • In the task-based image-quality assessments, SR-DLR yielded better spatial resolution, noise property, and detectability for objects simulating the coronary lumen, coronary calcifications, and noncalcified plaques than other reconstruction techniques. • The image reconstruction times of SR-DLR were shorter than those of MBIR, potentially serving as a novel standard-of-care reconstruction technique for CCTA performed on a 320-row CT scanner.
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Affiliation(s)
- Yasunori Nagayama
- Department of Diagnostic Radiology, Graduate School of Medical Sciences, Kumamoto University, 1-1-1, Honjo, Chuo-Ku, Kumamoto, 860-8556, Japan.
| | - Takafumi Emoto
- Department of Central Radiology, Kumamoto University Hospital, Kumamoto, Japan
| | - Yuki Kato
- Department of Diagnostic Radiology, Graduate School of Medical Sciences, Kumamoto University, 1-1-1, Honjo, Chuo-Ku, Kumamoto, 860-8556, Japan
| | - Masafumi Kidoh
- Department of Diagnostic Radiology, Graduate School of Medical Sciences, Kumamoto University, 1-1-1, Honjo, Chuo-Ku, Kumamoto, 860-8556, Japan
| | - Seitaro Oda
- Department of Diagnostic Radiology, Graduate School of Medical Sciences, Kumamoto University, 1-1-1, Honjo, Chuo-Ku, Kumamoto, 860-8556, Japan
| | - Daisuke Sakabe
- Department of Central Radiology, Kumamoto University Hospital, Kumamoto, Japan
| | - Yoshinori Funama
- Department of Medical Radiation Sciences, Faculty of Life Sciences, Kumamoto University, Kumamoto, Japan
| | - Takeshi Nakaura
- Department of Diagnostic Radiology, Graduate School of Medical Sciences, Kumamoto University, 1-1-1, Honjo, Chuo-Ku, Kumamoto, 860-8556, Japan
| | - Hidetaka Hayashi
- Department of Diagnostic Radiology, Graduate School of Medical Sciences, Kumamoto University, 1-1-1, Honjo, Chuo-Ku, Kumamoto, 860-8556, Japan
| | - Sentaro Takada
- Department of Diagnostic Radiology, Graduate School of Medical Sciences, Kumamoto University, 1-1-1, Honjo, Chuo-Ku, Kumamoto, 860-8556, Japan
| | - Ryutaro Uchimura
- Department of Diagnostic Radiology, Graduate School of Medical Sciences, Kumamoto University, 1-1-1, Honjo, Chuo-Ku, Kumamoto, 860-8556, Japan
| | - Masahiro Hatemura
- Department of Central Radiology, Kumamoto University Hospital, Kumamoto, Japan
| | - Kenichi Tsujita
- Department of Cardiovascular Medicine, Graduate School of Medical Sciences, Kumamoto University, Kumamoto, Japan
| | - Toshinori Hirai
- Department of Diagnostic Radiology, Graduate School of Medical Sciences, Kumamoto University, 1-1-1, Honjo, Chuo-Ku, Kumamoto, 860-8556, Japan
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Nagayama Y, Emoto T, Hayashi H, Kidoh M, Oda S, Nakaura T, Sakabe D, Funama Y, Tabata N, Ishii M, Yamanaga K, Fujisue K, Takashio S, Yamamoto E, Tsujita K, Hirai T. Coronary Stent Evaluation by CTA: Image Quality Comparison Between Super-Resolution Deep Learning Reconstruction and Other Reconstruction Algorithms. AJR Am J Roentgenol 2023; 221:599-610. [PMID: 37377362 DOI: 10.2214/ajr.23.29506] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/29/2023]
Abstract
BACKGROUND. A super-resolution deep learning reconstruction (SR-DLR) algorithm may provide better image sharpness than earlier reconstruction algorithms and thereby improve coronary stent assessment on coronary CTA. OBJECTIVE. The purpose of our study was to compare SR-DLR and other reconstruction algorithms in terms of image quality measures related to coronary stent evaluation in patients undergoing coronary CTA. METHODS. This retrospective study included patients with at least one coronary artery stent who underwent coronary CTA between January 2020 and December 2020. Examinations were performed using a 320-row normal-resolution scanner and were reconstructed with hybrid iterative reconstruction (HIR), model-based iterative reconstruction (MBIR), normal-resolution deep learning reconstruction (NR-DLR), and SR-DLR algorithms. Quantitative image quality measures were determined. Two radiologists independently reviewed images to rank the four reconstructions (4-point scale: 1 = worst reconstruction, 4 = best reconstruction) for qualitative measures and to score diagnostic confidence (5-point scale: score ≥ 3 indicating an assessable stent). The assessability rate was calculated for stents with a diameter of 3.0 mm or less. RESULTS. The sample included 24 patients (18 men, six women; mean age, 72.5 ± 9.8 [SD] years), with 51 stents. SR-DLR, in comparison with the other reconstructions, yielded lower stent-related blooming artifacts (median, 40.3 vs 53.4-58.2), stent-induced attenuation increase ratio (0.17 vs 0.27-0.31), and quantitative image noise (18.1 vs 20.9-30.4 HU) and higher in-stent lumen diameter (2.4 vs 1.7-1.9 mm), stent strut sharpness (327 vs 147-210 ΔHU/mm), and CNR (30.0 vs 16.0-25.6) (all p < .001). For both observers, all ranked measures (image sharpness; image noise; noise texture; delineation of stent strut, in-stent lumen, coronary artery wall, and calcified plaque surrounding the stent) and diagnostic confidence showed a higher score for SR-DLR (median, 4.0 for all features) than for the other reconstructions (range, 1.0-3.0) (all p < .001). The assessability rate for stents with a diameter of 3.0 mm or less (n = 37) was higher for SR-DLR (86.5% for observer 1 and 89.2% for observer 2) than for HIR (35.1% and 43.2%), MBIR (59.5% and 62.2%), and NR-DLR (62.2% and 64.9%) (all p < .05). CONCLUSION. SR-DLR yielded improved delineation of the stent strut and in-stent lumen, with better image sharpness and less image noise and blooming artifacts, in comparison with HIR, MBIR, and NR-DLR. CLINICAL IMPACT. SR-DLR may facilitate coronary stent assessment on a 320-row normal-resolution scanner, particularly for small-diameter stents.
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Affiliation(s)
- Yasunori Nagayama
- Department of Diagnostic Radiology, Graduate School of Medical Sciences, Kumamoto University, 1-1-1, Honjo, Chuo-ku, Kumamoto 860-8556, Japan
| | - Takafumi Emoto
- Department of Central Radiology, Kumamoto University Hospital, Kumamoto, Japan
| | - Hidetaka Hayashi
- Department of Diagnostic Radiology, Graduate School of Medical Sciences, Kumamoto University, 1-1-1, Honjo, Chuo-ku, Kumamoto 860-8556, Japan
| | - Masafumi Kidoh
- Department of Diagnostic Radiology, Graduate School of Medical Sciences, Kumamoto University, 1-1-1, Honjo, Chuo-ku, Kumamoto 860-8556, Japan
| | - Seitaro Oda
- Department of Diagnostic Radiology, Graduate School of Medical Sciences, Kumamoto University, 1-1-1, Honjo, Chuo-ku, Kumamoto 860-8556, Japan
| | - Takeshi Nakaura
- Department of Diagnostic Radiology, Graduate School of Medical Sciences, Kumamoto University, 1-1-1, Honjo, Chuo-ku, Kumamoto 860-8556, Japan
| | - Daisuke Sakabe
- Department of Central Radiology, Kumamoto University Hospital, Kumamoto, Japan
| | - Yoshinori Funama
- Department of Medical Radiation Sciences, Faculty of Life Sciences, Kumamoto University, Kumamoto, Japan
| | - Noriaki Tabata
- Department of Cardiovascular Medicine, Graduate School of Medical Sciences, Kumamoto University, Kumamoto, Japan
| | - Masanobu Ishii
- Department of Cardiovascular Medicine, Graduate School of Medical Sciences, Kumamoto University, Kumamoto, Japan
| | - Kenshi Yamanaga
- Department of Cardiovascular Medicine, Graduate School of Medical Sciences, Kumamoto University, Kumamoto, Japan
| | - Koichiro Fujisue
- Department of Cardiovascular Medicine, Graduate School of Medical Sciences, Kumamoto University, Kumamoto, Japan
| | - Seiji Takashio
- Department of Cardiovascular Medicine, Graduate School of Medical Sciences, Kumamoto University, Kumamoto, Japan
| | - Eiichiro Yamamoto
- Department of Cardiovascular Medicine, Graduate School of Medical Sciences, Kumamoto University, Kumamoto, Japan
| | - Kenichi Tsujita
- Department of Cardiovascular Medicine, Graduate School of Medical Sciences, Kumamoto University, Kumamoto, Japan
| | - Toshinori Hirai
- Department of Diagnostic Radiology, Graduate School of Medical Sciences, Kumamoto University, 1-1-1, Honjo, Chuo-ku, Kumamoto 860-8556, Japan
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Nagayama Y, Iwashita K, Maruyama N, Uetani H, Goto M, Sakabe D, Emoto T, Nakato K, Shigematsu S, Kato Y, Takada S, Kidoh M, Oda S, Nakaura T, Hatemura M, Ueda M, Mukasa A, Hirai T. Deep learning-based reconstruction can improve the image quality of low radiation dose head CT. Eur Radiol 2023; 33:3253-3265. [PMID: 36973431 DOI: 10.1007/s00330-023-09559-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2022] [Revised: 12/06/2022] [Accepted: 02/06/2023] [Indexed: 03/29/2023]
Abstract
OBJECTIVES To evaluate the image quality of deep learning-based reconstruction (DLR), model-based (MBIR), and hybrid iterative reconstruction (HIR) algorithms for lower-dose (LD) unenhanced head CT and compare it with those of standard-dose (STD) HIR images. METHODS This retrospective study included 114 patients who underwent unenhanced head CT using the STD (n = 57) or LD (n = 57) protocol on a 320-row CT. STD images were reconstructed with HIR; LD images were reconstructed with HIR (LD-HIR), MBIR (LD-MBIR), and DLR (LD-DLR). The image noise, gray and white matter (GM-WM) contrast, and contrast-to-noise ratio (CNR) at the basal ganglia and posterior fossa levels were quantified. The noise magnitude, noise texture, GM-WM contrast, image sharpness, streak artifact, and subjective acceptability were independently scored by three radiologists (1 = worst, 5 = best). The lesion conspicuity of LD-HIR, LD-MBIR, and LD-DLR was ranked through side-by-side assessments (1 = worst, 3 = best). Reconstruction times of three algorithms were measured. RESULTS The effective dose of LD was 25% lower than that of STD. Lower image noise, higher GM-WM contrast, and higher CNR were observed in LD-DLR and LD-MBIR than those in STD (all, p ≤ 0.035). Compared with STD, the noise texture, image sharpness, and subjective acceptability were inferior for LD-MBIR and superior for LD-DLR (all, p < 0.001). The lesion conspicuity of LD-DLR (2.9 ± 0.2) was higher than that of HIR (1.2 ± 0.3) and MBIR (1.8 ± 0.4) (all, p < 0.001). Reconstruction times of HIR, MBIR, and DLR were 11 ± 1, 319 ± 17, and 24 ± 1 s, respectively. CONCLUSION DLR can enhance the image quality of head CT while preserving low radiation dose level and short reconstruction time. KEY POINTS • For unenhanced head CT, DLR reduced the image noise and improved the GM-WM contrast and lesion delineation without sacrificing the natural noise texture and image sharpness relative to HIR. • The subjective and objective image quality of DLR was better than that of HIR even at 25% reduced dose without considerably increasing the image reconstruction times (24 s vs. 11 s). • Despite the strong noise reduction and improved GM-WM contrast performance, MBIR degraded the noise texture, sharpness, and subjective acceptance with prolonged reconstruction times relative to HIR, potentially hampering its feasibility.
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Affiliation(s)
- Yasunori Nagayama
- Department of Diagnostic Radiology, Graduate School of Medical Sciences, Kumamoto University, 1-1-1, Honjo, Chuo-Ku, Kumamoto, 860-8556, Japan.
| | - Koya Iwashita
- Department of Diagnostic Radiology, Graduate School of Medical Sciences, Kumamoto University, 1-1-1, Honjo, Chuo-Ku, Kumamoto, 860-8556, Japan
| | - Natsuki Maruyama
- Department of Diagnostic Radiology, Graduate School of Medical Sciences, Kumamoto University, 1-1-1, Honjo, Chuo-Ku, Kumamoto, 860-8556, Japan
| | - Hiroyuki Uetani
- Department of Diagnostic Radiology, Graduate School of Medical Sciences, Kumamoto University, 1-1-1, Honjo, Chuo-Ku, Kumamoto, 860-8556, Japan
| | - Makoto Goto
- Department of Central Radiology, Kumamoto University Hospital, 1-1-1, Honjo, Chuo-Ku, Kumamoto, 860-8556, Japan
| | - Daisuke Sakabe
- Department of Central Radiology, Kumamoto University Hospital, 1-1-1, Honjo, Chuo-Ku, Kumamoto, 860-8556, Japan
| | - Takafumi Emoto
- Department of Central Radiology, Kumamoto University Hospital, 1-1-1, Honjo, Chuo-Ku, Kumamoto, 860-8556, Japan
| | - Kengo Nakato
- Department of Central Radiology, Kumamoto University Hospital, 1-1-1, Honjo, Chuo-Ku, Kumamoto, 860-8556, Japan
| | - Shinsuke Shigematsu
- Department of Central Radiology, Kumamoto University Hospital, 1-1-1, Honjo, Chuo-Ku, Kumamoto, 860-8556, Japan
| | - Yuki Kato
- Department of Diagnostic Radiology, Graduate School of Medical Sciences, Kumamoto University, 1-1-1, Honjo, Chuo-Ku, Kumamoto, 860-8556, Japan
| | - Sentaro Takada
- Department of Diagnostic Radiology, Graduate School of Medical Sciences, Kumamoto University, 1-1-1, Honjo, Chuo-Ku, Kumamoto, 860-8556, Japan
| | - Masafumi Kidoh
- Department of Diagnostic Radiology, Graduate School of Medical Sciences, Kumamoto University, 1-1-1, Honjo, Chuo-Ku, Kumamoto, 860-8556, Japan
| | - Seitaro Oda
- Department of Diagnostic Radiology, Graduate School of Medical Sciences, Kumamoto University, 1-1-1, Honjo, Chuo-Ku, Kumamoto, 860-8556, Japan
| | - Takeshi Nakaura
- Department of Diagnostic Radiology, Graduate School of Medical Sciences, Kumamoto University, 1-1-1, Honjo, Chuo-Ku, Kumamoto, 860-8556, Japan
| | - Masahiro Hatemura
- Department of Central Radiology, Kumamoto University Hospital, 1-1-1, Honjo, Chuo-Ku, Kumamoto, 860-8556, Japan
| | - Mitsuharu Ueda
- Department of Neurology, Graduate School of Medical Sciences, Kumamoto University, 1-1-1, Honjo, Chuo-Ku, Kumamoto, 860-8556, Japan
| | - Akitake Mukasa
- Department of Neurosurgery, Graduate School of Medical Sciences, Kumamoto University, 1-1-1, Honjo, Chuo-Ku, Kumamoto, 860-8556, Japan
| | - Toshinori Hirai
- Department of Diagnostic Radiology, Graduate School of Medical Sciences, Kumamoto University, 1-1-1, Honjo, Chuo-Ku, Kumamoto, 860-8556, Japan
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Kidoh M, Oda S, Takashio S, Kawano Y, Hayashi H, Morita K, Emoto T, Shigematsu S, Yoshimura F, Nakaura T, Nagayama Y, Matsuoka M, Ueda M, Tsujita K, Hirai T. Cardiac MRI-derived Extracellular Volume Fraction versus Myocardium-to-Lumen R1 Ratio at Postcontrast T1 Mapping for Detecting Cardiac Amyloidosis. Radiol Cardiothorac Imaging 2023; 5:e220327. [PMID: 37124644 PMCID: PMC10141336 DOI: 10.1148/ryct.220327] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2022] [Revised: 03/02/2023] [Accepted: 03/14/2023] [Indexed: 05/02/2023]
Abstract
Purpose To evaluate the diagnostic performance of myocardium-to-lumen R1 (1/T1) ratio on postcontrast T1 maps for the detection of cardiac amyloidosis in a large patient sample. Materials and Methods This retrospective study included consecutive patients who underwent MRI-derived extracellular volume fraction (MRI ECV) analysis between March 2017 and July 2021 because of known or suspected heart failure or cardiomyopathy. Pre- and postcontrast T1 maps were generated using the modified Look-Locker inversion recovery sequence. Diagnostic performances of MRI ECV and myocardium-to-lumen R1 ratio on postcontrast T1 maps (a simplified index not requiring a native T1 map and hematocrit level data) for detecting cardiac amyloidosis were evaluated using the area under the receiver operating characteristic curve (AUC), sensitivity, and specificity. Results Of 352 patients (mean age, 63 years ± 16 [SD]; 235 men), 136 had cardiac amyloidosis. MRI ECV showed 89.0% (121 of 136; 95% CI: 82%, 94%) sensitivity and 98.6% (213 of 216; 95% CI: 96%, 100%) specificity for helping detect cardiac amyloidosis (cutoff value of 40% [AUC, 0.99 {95% CI: 0.97, 1.00}; P < .001]). Postcontrast myocardium-to-lumen R1 ratio showed 92.6% (126 of 136; 95% CI: 89%, 96%) sensitivity and 93.1% (201 of 216; 95% CI: 89%, 96%) specificity (cutoff value of 0.84 [AUC, 0.98 {95% CI: 0.95, 0.99}; P < .001]). There was no evidence of a difference in AUCs for each parameter (P = .10). Conclusion Postcontrast myocardium-to-lumen R1 ratio showed excellent diagnostic performance comparable to that of MRI ECV in the detection of cardiac amyloidosis.Keywords: MR Imaging, Cardiac, Heart, Cardiomyopathies Supplemental material is available for this article. © RSNA, 2023.
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Goto M, Nagayama Y, Sakabe D, Emoto T, Kidoh M, Oda S, Nakaura T, Taguchi N, Funama Y, Takada S, Uchimura R, Hayashi H, Hatemura M, Kawanaka K, Hirai T. Lung-Optimized Deep-Learning-Based Reconstruction for Ultralow-Dose CT. Acad Radiol 2023; 30:431-440. [PMID: 35738988 DOI: 10.1016/j.acra.2022.04.025] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2022] [Revised: 04/18/2022] [Accepted: 04/30/2022] [Indexed: 01/25/2023]
Abstract
RATIONALE AND OBJECTIVES To evaluate the image properties of lung-specialized deep-learning-based reconstruction (DLR) and its applicability in ultralow-dose CT (ULDCT) relative to hybrid- (HIR) and model-based iterative-reconstructions (MBIR). MATERIALS AND METHODS An anthropomorphic chest phantom was scanned on a 320-row scanner at 50-mA (low-dose-CT 1 [LDCT-1]), 25-mA (LDCT-2), and 10-mA (ULDCT). LDCT were reconstructed with HIR; ULDCT images were reconstructed with HIR (ULDCT-HIR), MBIR (ULDCT-MBIR), and DLR (ULDCT-DLR). Image noise and contrast-to-noise ratio (CNR) were quantified. With the LDCT images as reference standards, ULDCT image qualities were subjectively scored on a 5-point scale (1 = substantially inferior to LDCT-2, 3 = comparable to LDCT-2, 5 = comparable to LDCT-1). For task-based image quality analyses, a physical evaluation phantom was scanned at seven doses to achieve the noise levels equivalent to chest phantom; noise power spectrum (NPS) and task-based transfer function (TTF) were evaluated. Clinical ULDCT (10-mA) images obtained in 14 nonobese patients were reconstructed with HIR, MBIR, and DLR; the subjective acceptability was ranked. RESULTS Image noise was lower and CNR was higher in ULDCT-DLR and ULDCT-MBIR than in LDCT-1, LDCT-2, and ULDCT-HIR (p < 0.01). The overall quality of ULDCT-DLR was higher than of ULDCT-HIR and ULDCT-MBIR (p < 0.01), and almost comparable with that of LDCT-2 (mean score: 3.4 ± 0.5). DLR yielded the highest NPS peak frequency and TTF50% for high-contrast object. In clinical ULDCT images, the subjective acceptability of DLR was higher than of HIR and MBIR (p < 0.01). CONCLUSION DLR optimized for lung CT improves image quality and provides possible greater dose optimization opportunity than HIR and MBIR.
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Affiliation(s)
- Makoto Goto
- Department of Central Radiology, Kumamoto University Hospital, Chuo-ku, Kumamoto 860-8556, Japan
| | - Yasunori Nagayama
- Department of Diagnostic Radiology, Graduate School of Medical Sciences, Kumamoto University, 1-1-1, Honjo, Chuo-ku, Kumamoto 860-8556, Japan.
| | - Daisuke Sakabe
- Department of Central Radiology, Kumamoto University Hospital, Chuo-ku, Kumamoto 860-8556, Japan
| | - Takafumi Emoto
- Department of Central Radiology, Kumamoto University Hospital, Chuo-ku, Kumamoto 860-8556, Japan
| | - Masafumi Kidoh
- Department of Diagnostic Radiology, Graduate School of Medical Sciences, Kumamoto University, 1-1-1, Honjo, Chuo-ku, Kumamoto 860-8556, Japan
| | - Seitaro Oda
- Department of Diagnostic Radiology, Graduate School of Medical Sciences, Kumamoto University, 1-1-1, Honjo, Chuo-ku, Kumamoto 860-8556, Japan
| | - Takeshi Nakaura
- Department of Diagnostic Radiology, Graduate School of Medical Sciences, Kumamoto University, 1-1-1, Honjo, Chuo-ku, Kumamoto 860-8556, Japan
| | - Narumi Taguchi
- Department of Diagnostic Radiology, Graduate School of Medical Sciences, Kumamoto University, 1-1-1, Honjo, Chuo-ku, Kumamoto 860-8556, Japan
| | - Yoshinori Funama
- Department of Medical Radiation Sciences, Faculty of Life Sciences, Kumamoto University, Chuo-ku, Kumamoto 862-0976, Japan
| | - Sentaro Takada
- Department of Diagnostic Radiology, Graduate School of Medical Sciences, Kumamoto University, 1-1-1, Honjo, Chuo-ku, Kumamoto 860-8556, Japan
| | - Ryutaro Uchimura
- Department of Diagnostic Radiology, Graduate School of Medical Sciences, Kumamoto University, 1-1-1, Honjo, Chuo-ku, Kumamoto 860-8556, Japan
| | - Hidetaka Hayashi
- Department of Diagnostic Radiology, Graduate School of Medical Sciences, Kumamoto University, 1-1-1, Honjo, Chuo-ku, Kumamoto 860-8556, Japan
| | - Masahiro Hatemura
- Department of Central Radiology, Kumamoto University Hospital, Chuo-ku, Kumamoto 860-8556, Japan
| | - Koichi Kawanaka
- Department of Diagnostic Radiology, Graduate School of Medical Sciences, Kumamoto University, 1-1-1, Honjo, Chuo-ku, Kumamoto 860-8556, Japan
| | - Toshinori Hirai
- Department of Diagnostic Radiology, Graduate School of Medical Sciences, Kumamoto University, 1-1-1, Honjo, Chuo-ku, Kumamoto 860-8556, Japan
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Nagayama Y, Goto M, Sakabe D, Emoto T, Shigematsu S, Taguchi N, Maruyama N, Takada S, Uchimura R, Hayashi H, Kidoh M, Oda S, Nakaura T, Funama Y, Hatemura M, Hirai T. Radiation dose optimization potential of deep learning-based reconstruction for multiphase hepatic CT: A clinical and phantom study. Eur J Radiol 2022; 151:110280. [PMID: 35381567 DOI: 10.1016/j.ejrad.2022.110280] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2021] [Revised: 03/02/2022] [Accepted: 03/28/2022] [Indexed: 11/03/2022]
Abstract
PURPOSE This clinical and phantom study aimed to evaluate the impact of deep learning-based reconstruction (DLR) on image quality and its radiation dose optimization capability for multiphase hepatic CT relative to hybrid iterative reconstruction (HIR). METHODS Task-based image quality was assessed with a physical evaluation phantom; the high- and low-contrast detectability of HIR and DLR images were computed from the noise power spectrum and task-based transfer function at five different size-specific dose estimate (SSDE) values in the range 5.3 to 18.0-mGy. For the clinical study, images of 73 patients who had undergone multiphase hepatic CT under both standard-dose (STD) and lower-dose (LD) examination protocols within a time interval of about four-months on average, were retrospectively examined. STD images were reconstructed with HIR, while LD with HIR (LD-HIR) and DLR (LD-DLR). SSDE, quantitative image noise, and contrast-to-noise ratio (CNR) were compared between protocols. The noise magnitude, noise texture, streak artifact, image sharpness, interface smoothness, and overall image quality were subjectively rated by two independent radiologists. RESULTS In phantom study, the high- and low-contrast detectability of DLR images obtained at 5.3-mGy and 7.3-mGy, respectively, were slightly higher than those obtained with HIR at the STD protocol dose (18.0-mGy). In clinical study, LD-DLR yielded lower image noise, higher CNR, and higher subjective scores for all evaluation criteria than STD (all, p ≤ 0.05), despite having 52.8% lower SSDE (8.0 ± 2.5 vs. 16.8 ± 3.4-mGy). CONCLUSIONS DLR improved the subjective and objective image quality of multiphase hepatic CT compared with HIR techniques, even at approximately half the radiation dose.
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Affiliation(s)
- Yasunori Nagayama
- Department of Diagnostic Radiology, Graduate School of Medical Sciences, Kumamoto University, 1-1-1, Honjo, Chuo-ku, Kumamoto 860-8556, Japan.
| | - Makoto Goto
- Department of Central Radiology, Kumamoto University Hospital, 1-1-1, Honjo, Chuo-ku, Kumamoto 860-8556, Japan
| | - Daisuke Sakabe
- Department of Central Radiology, Kumamoto University Hospital, 1-1-1, Honjo, Chuo-ku, Kumamoto 860-8556, Japan
| | - Takafumi Emoto
- Department of Central Radiology, Kumamoto University Hospital, 1-1-1, Honjo, Chuo-ku, Kumamoto 860-8556, Japan
| | - Shinsuke Shigematsu
- Department of Central Radiology, Kumamoto University Hospital, 1-1-1, Honjo, Chuo-ku, Kumamoto 860-8556, Japan
| | - Narumi Taguchi
- Department of Diagnostic Radiology, Graduate School of Medical Sciences, Kumamoto University, 1-1-1, Honjo, Chuo-ku, Kumamoto 860-8556, Japan
| | - Natsuki Maruyama
- Department of Diagnostic Radiology, Graduate School of Medical Sciences, Kumamoto University, 1-1-1, Honjo, Chuo-ku, Kumamoto 860-8556, Japan
| | - Sentaro Takada
- Department of Diagnostic Radiology, Graduate School of Medical Sciences, Kumamoto University, 1-1-1, Honjo, Chuo-ku, Kumamoto 860-8556, Japan
| | - Ryutaro Uchimura
- Department of Diagnostic Radiology, Graduate School of Medical Sciences, Kumamoto University, 1-1-1, Honjo, Chuo-ku, Kumamoto 860-8556, Japan
| | - Hidetaka Hayashi
- Department of Diagnostic Radiology, Graduate School of Medical Sciences, Kumamoto University, 1-1-1, Honjo, Chuo-ku, Kumamoto 860-8556, Japan
| | - Masafumi Kidoh
- Department of Diagnostic Radiology, Graduate School of Medical Sciences, Kumamoto University, 1-1-1, Honjo, Chuo-ku, Kumamoto 860-8556, Japan
| | - Seitaro Oda
- Department of Diagnostic Radiology, Graduate School of Medical Sciences, Kumamoto University, 1-1-1, Honjo, Chuo-ku, Kumamoto 860-8556, Japan
| | - Takeshi Nakaura
- Department of Diagnostic Radiology, Graduate School of Medical Sciences, Kumamoto University, 1-1-1, Honjo, Chuo-ku, Kumamoto 860-8556, Japan
| | - Yoshinori Funama
- Department of Medical Radiation Sciences, Faculty of Life Sciences, Kumamoto University, 4-24-1 Kuhonji, Chuo-ku, Kumamoto 862-0976, Japan
| | - Masahiro Hatemura
- Department of Central Radiology, Kumamoto University Hospital, 1-1-1, Honjo, Chuo-ku, Kumamoto 860-8556, Japan
| | - Toshinori Hirai
- Department of Diagnostic Radiology, Graduate School of Medical Sciences, Kumamoto University, 1-1-1, Honjo, Chuo-ku, Kumamoto 860-8556, Japan
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Hayashi H, Oda S, Emoto T, Kidoh M, Nagayama Y, Nakaura T, Sakabe D, Tokuyasu S, Hirakawa K, Takashio S, Yamamoto E, Tsujita K, Hirai T. Myocardial extracellular volume quantification by cardiac CT in pulmonary hypertension: Comparison with cardiac MRI. Eur J Radiol 2022; 153:110386. [PMID: 35661458 DOI: 10.1016/j.ejrad.2022.110386] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2022] [Revised: 05/21/2022] [Accepted: 05/26/2022] [Indexed: 11/03/2022]
Abstract
PURPOSE Myocardial extracellular volume (ECV) measured by cardiac magnetic resonance imaging (MRI) has been suggested as a marker of disease severity in pulmonary hypertension (PH). However, consistency between ECVs quantified by computed tomography (CT) and MRI has not been sufficiently investigated in (PH). We investigated the utility of CT-ECV in PH, using MRI-ECV as a reference standard. METHOD We evaluated 20 patients with known or suspected PH who underwent dual-energy CT, cardiac MRI, and right heart catheterization. We used Pearson correlation analysis to investigate correlations between CT-ECV and MRI-ECV. We also assessed correlations between ECV and mean pulmonary artery pressure (mPAP). RESULTS CT-ECV showed a very strong correlation with MRI-ECV at the anterior (r = 0.83) and posterior right ventricular insertion points (RVIPs) (r = 0.84). CT-ECV and MRI-ECV were strongly correlated in the septum and left ventricular free wall (r = 0.79-0.73) but weakly correlated in the right ventricular free wall (r = 0.26). CT-ECV showed a strong correlation with mPAP in the anterior RVIP (r = 0.64) and a moderate correlation in the posterior RVIP and septum (r = 0.50-0.42). Compared with CT-ECV, MRI-ECV had a higher correlation with mPAP; however, the difference was not significant (anterior RVIP, r = 0.72 [MRI-ECV] vs. 0.64 [CT-ECV], p = 0.663; posterior RVIP, r = 0.67 vs. 0.50, p = 0.446). CONCLUSION Dual-energy CT can quantify myocardial ECV and yield results comparable to those obtained using cardiac MRI. CT-ECV in the anterior RVIP could be a noninvasive surrogate marker of disease severity in PH.
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Affiliation(s)
- Hidetaka Hayashi
- Department of Diagnostic Radiology, Faculty of Life Sciences, Kumamoto University, 1-1-1 Honjyo, Chuo-ku, Kumamoto 860-8556, Japan
| | - Seitaro Oda
- Department of Diagnostic Radiology, Faculty of Life Sciences, Kumamoto University, 1-1-1 Honjyo, Chuo-ku, Kumamoto 860-8556, Japan.
| | - Takafumi Emoto
- Department of Central Radiology, Kumamoto University Hospital, 1-1-1 Honjyo, Chuo-ku, Kumamoto 860-8556, Japan
| | - Masafumi Kidoh
- Department of Diagnostic Radiology, Faculty of Life Sciences, Kumamoto University, 1-1-1 Honjyo, Chuo-ku, Kumamoto 860-8556, Japan
| | - Yasunori Nagayama
- Department of Diagnostic Radiology, Faculty of Life Sciences, Kumamoto University, 1-1-1 Honjyo, Chuo-ku, Kumamoto 860-8556, Japan
| | - Takeshi Nakaura
- Department of Diagnostic Radiology, Faculty of Life Sciences, Kumamoto University, 1-1-1 Honjyo, Chuo-ku, Kumamoto 860-8556, Japan
| | - Daisuke Sakabe
- Department of Central Radiology, Kumamoto University Hospital, 1-1-1 Honjyo, Chuo-ku, Kumamoto 860-8556, Japan
| | - Shinichi Tokuyasu
- CT Clinical Science, Philips Japan, Kohnan 2-13-37, Minato-ku, Tokyo 108-8507, Japan
| | - Kyoko Hirakawa
- Department of Cardiovascular Medicine, Faculty of Life Sciences, Kumamoto University, 1-1-1 Honjyo, Chuo-ku, Kumamoto 860-8556, Japan
| | - Seiji Takashio
- Department of Cardiovascular Medicine, Faculty of Life Sciences, Kumamoto University, 1-1-1 Honjyo, Chuo-ku, Kumamoto 860-8556, Japan
| | - Eiichiro Yamamoto
- Department of Cardiovascular Medicine, Faculty of Life Sciences, Kumamoto University, 1-1-1 Honjyo, Chuo-ku, Kumamoto 860-8556, Japan
| | - Kenichi Tsujita
- Department of Cardiovascular Medicine, Faculty of Life Sciences, Kumamoto University, 1-1-1 Honjyo, Chuo-ku, Kumamoto 860-8556, Japan
| | - Toshinori Hirai
- Department of Diagnostic Radiology, Faculty of Life Sciences, Kumamoto University, 1-1-1 Honjyo, Chuo-ku, Kumamoto 860-8556, Japan
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Nagayama Y, Sakabe D, Goto M, Emoto T, Oda S, Nakaura T, Kidoh M, Uetani H, Funama Y, Hirai T. Deep Learning-based Reconstruction for Lower-Dose Pediatric CT: Technical Principles, Image Characteristics, and Clinical Implementations. Radiographics 2021; 41:1936-1953. [PMID: 34597178 DOI: 10.1148/rg.2021210105] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Optimizing the CT acquisition parameters to obtain diagnostic image quality at the lowest possible radiation dose is crucial in the radiosensitive pediatric population. The image quality of low-dose CT can be severely degraded by increased image noise with filtered back projection (FBP) reconstruction. Iterative reconstruction (IR) techniques partially resolve the trade-off relationship between noise and radiation dose but still suffer from degraded noise texture and low-contrast detectability at considerably low-dose settings. Furthermore, sophisticated model-based IR usually requires a long reconstruction time, which restricts its clinical usability. With recent advances in artificial intelligence technology, deep learning-based reconstruction (DLR) has been introduced to overcome the limitations of the FBP and IR approaches and is currently available clinically. DLR incorporates convolutional neural networks-which comprise multiple layers of mathematical equations-into the image reconstruction process to reduce image noise, improve spatial resolution, and preserve preferable noise texture in the CT images. For DLR development, numerous network parameters are iteratively optimized through an extensive learning process to discriminate true attenuation from noise by using low-dose training and high-dose teaching image data. After rigorous validations of network generalizability, the DLR engine can be used to generate high-quality images from low-dose projection data in a short reconstruction time in a clinical environment. Application of the DLR technique allows substantial dose reduction in pediatric CT performed for various clinical indications while preserving the diagnostic image quality. The authors present an overview of the basic concept, technical principles, and image characteristics of DLR and its clinical feasibility for low-dose pediatric CT. ©RSNA, 2021.
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Affiliation(s)
- Yasunori Nagayama
- From the Department of Diagnostic Radiology, Graduate School of Medical Sciences (Y.N., S.O., T.N., M.K., H.U., T.H.), and Department of Medical Radiation Sciences, Faculty of Life Sciences (Y.F.), Kumamoto University, 1-1-1 Honjo, Chuo-ku, Kumamoto 860-8556, Japan; and Department of Central Radiology, Kumamoto University Hospital, Chuo-ku, Kumamoto, Japan (D.S., M.G., T.E.)
| | - Daisuke Sakabe
- From the Department of Diagnostic Radiology, Graduate School of Medical Sciences (Y.N., S.O., T.N., M.K., H.U., T.H.), and Department of Medical Radiation Sciences, Faculty of Life Sciences (Y.F.), Kumamoto University, 1-1-1 Honjo, Chuo-ku, Kumamoto 860-8556, Japan; and Department of Central Radiology, Kumamoto University Hospital, Chuo-ku, Kumamoto, Japan (D.S., M.G., T.E.)
| | - Makoto Goto
- From the Department of Diagnostic Radiology, Graduate School of Medical Sciences (Y.N., S.O., T.N., M.K., H.U., T.H.), and Department of Medical Radiation Sciences, Faculty of Life Sciences (Y.F.), Kumamoto University, 1-1-1 Honjo, Chuo-ku, Kumamoto 860-8556, Japan; and Department of Central Radiology, Kumamoto University Hospital, Chuo-ku, Kumamoto, Japan (D.S., M.G., T.E.)
| | - Takafumi Emoto
- From the Department of Diagnostic Radiology, Graduate School of Medical Sciences (Y.N., S.O., T.N., M.K., H.U., T.H.), and Department of Medical Radiation Sciences, Faculty of Life Sciences (Y.F.), Kumamoto University, 1-1-1 Honjo, Chuo-ku, Kumamoto 860-8556, Japan; and Department of Central Radiology, Kumamoto University Hospital, Chuo-ku, Kumamoto, Japan (D.S., M.G., T.E.)
| | - Seitaro Oda
- From the Department of Diagnostic Radiology, Graduate School of Medical Sciences (Y.N., S.O., T.N., M.K., H.U., T.H.), and Department of Medical Radiation Sciences, Faculty of Life Sciences (Y.F.), Kumamoto University, 1-1-1 Honjo, Chuo-ku, Kumamoto 860-8556, Japan; and Department of Central Radiology, Kumamoto University Hospital, Chuo-ku, Kumamoto, Japan (D.S., M.G., T.E.)
| | - Takeshi Nakaura
- From the Department of Diagnostic Radiology, Graduate School of Medical Sciences (Y.N., S.O., T.N., M.K., H.U., T.H.), and Department of Medical Radiation Sciences, Faculty of Life Sciences (Y.F.), Kumamoto University, 1-1-1 Honjo, Chuo-ku, Kumamoto 860-8556, Japan; and Department of Central Radiology, Kumamoto University Hospital, Chuo-ku, Kumamoto, Japan (D.S., M.G., T.E.)
| | - Masafumi Kidoh
- From the Department of Diagnostic Radiology, Graduate School of Medical Sciences (Y.N., S.O., T.N., M.K., H.U., T.H.), and Department of Medical Radiation Sciences, Faculty of Life Sciences (Y.F.), Kumamoto University, 1-1-1 Honjo, Chuo-ku, Kumamoto 860-8556, Japan; and Department of Central Radiology, Kumamoto University Hospital, Chuo-ku, Kumamoto, Japan (D.S., M.G., T.E.)
| | - Hiroyuki Uetani
- From the Department of Diagnostic Radiology, Graduate School of Medical Sciences (Y.N., S.O., T.N., M.K., H.U., T.H.), and Department of Medical Radiation Sciences, Faculty of Life Sciences (Y.F.), Kumamoto University, 1-1-1 Honjo, Chuo-ku, Kumamoto 860-8556, Japan; and Department of Central Radiology, Kumamoto University Hospital, Chuo-ku, Kumamoto, Japan (D.S., M.G., T.E.)
| | - Yoshinori Funama
- From the Department of Diagnostic Radiology, Graduate School of Medical Sciences (Y.N., S.O., T.N., M.K., H.U., T.H.), and Department of Medical Radiation Sciences, Faculty of Life Sciences (Y.F.), Kumamoto University, 1-1-1 Honjo, Chuo-ku, Kumamoto 860-8556, Japan; and Department of Central Radiology, Kumamoto University Hospital, Chuo-ku, Kumamoto, Japan (D.S., M.G., T.E.)
| | - Toshinori Hirai
- From the Department of Diagnostic Radiology, Graduate School of Medical Sciences (Y.N., S.O., T.N., M.K., H.U., T.H.), and Department of Medical Radiation Sciences, Faculty of Life Sciences (Y.F.), Kumamoto University, 1-1-1 Honjo, Chuo-ku, Kumamoto 860-8556, Japan; and Department of Central Radiology, Kumamoto University Hospital, Chuo-ku, Kumamoto, Japan (D.S., M.G., T.E.)
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Kidoh M, Oda S, Takashio S, Kanazawa H, Ikebe S, Emoto T, Nakaura T, Nagayama Y, Sasao A, Inoue T, Funama Y, Araki S, Yamamoto E, Kaikita K, Tsujita K, Ikeda O. Assessment of Diffuse Ventricular Fibrosis in Atrial Fibrillation Using Cardiac CT-Derived Myocardial Extracellular Volume Fraction. JACC Clin Electrophysiol 2020; 6:1573-1575. [PMID: 33213818 DOI: 10.1016/j.jacep.2020.06.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2020] [Revised: 05/26/2020] [Accepted: 06/10/2020] [Indexed: 10/23/2022]
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Nagayama Y, Tanoue S, Oda S, Sakabe D, Emoto T, Kidoh M, Uetani H, Sasao A, Nakaura T, Ikeda O, Yamada K, Yamashita Y. Metal Artifact Reduction in Head CT Performed for Patients with Deep Brain Stimulation Devices: Effectiveness of a Single-Energy Metal Artifact Reduction Algorithm. AJNR Am J Neuroradiol 2020; 41:231-237. [PMID: 31879332 DOI: 10.3174/ajnr.a6375] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2019] [Accepted: 11/15/2019] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE Deep brain stimulation electrodes induce massive artifacts on CT images, deteriorating the diagnostic value of examinations. We aimed to investigate the usefulness and potential limitations of a single-energy metal artifact reduction algorithm in head CT performed in patients with implanted deep brain stimulation devices. MATERIALS AND METHODS Thirty-four patients with deep brain stimulation (bilateral, n = 28) who underwent head CT on a 320-detector row scanner and whose images were reconstructed with and without single-energy metal artifact reduction at the examinations were retrospectively included. The severity of artifacts around electrodes was assessed objectively using SDs and an artifact index. Two radiologists subjectively evaluated the severity of artifacts from electrodes, the visibility of electrode localization and surrounding structures, and overall diagnostic confidence on 4-point scales. Background image quality (GM-WM contrast and image noise) was subjectively and objectively assessed. The presence and location of artifacts newly produced by single-energy metal artifact reduction were analyzed. RESULTS Single-energy metal artifact reduction provided lower objective and subjective metal artifacts and improved visualization of electrode localization and surrounding structures and diagnostic confidence compared with non-single-energy metal artifact reduction images, with statistical significance (all, P < .01). No significant differences were observed in GM-WM contrast and image noise (all, P ≥ .11). The new artifacts from single-energy metal artifact reduction were prominently observed in patients with bilateral deep brain stimulation at high convexity, possibly induced by deep brain stimulation leads placed under the parietal scalp. CONCLUSIONS Single-energy metal artifact reduction substantially reduces the metal artifacts from deep brain stimulation electrodes and improves the visibility of intracranial structures without affecting background image quality. However, non-single-energy metal artifact reduction images should be simultaneously reviewed to accurately assess the entire intracranial area, particularly in patients with bilateral deep brain stimulation.
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Affiliation(s)
- Y Nagayama
- From the Department of Diagnostic Radiology (Y.N., S.O., M.K., H.U., A.S., T.N., O.I., Y.Y.)
| | - S Tanoue
- Diagnostic Radiology (S.T.), Graduate School of Life Sciences, Kumamoto University, Kumamoto, Japan
| | - S Oda
- From the Department of Diagnostic Radiology (Y.N., S.O., M.K., H.U., A.S., T.N., O.I., Y.Y.)
| | - D Sakabe
- Department of Central Radiology (D.S., T.E.), Kumamoto University Hospital, Kumamoto, Japan
| | - T Emoto
- Department of Central Radiology (D.S., T.E.), Kumamoto University Hospital, Kumamoto, Japan
| | - M Kidoh
- From the Department of Diagnostic Radiology (Y.N., S.O., M.K., H.U., A.S., T.N., O.I., Y.Y.)
| | - H Uetani
- From the Department of Diagnostic Radiology (Y.N., S.O., M.K., H.U., A.S., T.N., O.I., Y.Y.)
| | - A Sasao
- From the Department of Diagnostic Radiology (Y.N., S.O., M.K., H.U., A.S., T.N., O.I., Y.Y.)
| | - T Nakaura
- From the Department of Diagnostic Radiology (Y.N., S.O., M.K., H.U., A.S., T.N., O.I., Y.Y.)
| | - O Ikeda
- From the Department of Diagnostic Radiology (Y.N., S.O., M.K., H.U., A.S., T.N., O.I., Y.Y.)
| | - K Yamada
- Graduate School of Medical Sciences, and Departments of Neurosurgery (K.Y.)
| | - Y Yamashita
- From the Department of Diagnostic Radiology (Y.N., S.O., M.K., H.U., A.S., T.N., O.I., Y.Y.)
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11
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Amin H, Sasaki N, Yamashita T, Mizoguchi T, Hayashi T, Emoto T, Matsumoto T, Yoshida N, Tabata T, Horibe S, Kawauchi S, Rikitake Y, Hirata K. 1436Overexpression of Cytotoxic T-Lymphocyte Associated Antigen-4 suppresses aortic immunoinflammatory responses and prevents angiotensin II-induced abdominal aortic aneurysm formation in mice. Eur Heart J 2019. [DOI: 10.1093/eurheartj/ehz748.0071] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Abstract
Aims
Vascular inflammation via T-cell-mediated immune responses has been shown to be critically involved in the pathogenesis of abdominal aortic aneurysm (AAA). T-cell coinhibitory molecule cytotoxic T-lymphocyte–associated antigen-4 (CTLA-4) is known to act as a potent negative regulator of immune responses. However, the role of this molecule in the development of AAA remains completely unknown. In the present study, we determined the effects of CTLA-4 overexpression on experimental AAA.
Methods and results
We continuously infused 12-week-old CTLA-4 transgenic (CTLA-4-Tg)/apolipoprotein E–deficient (Apoe−/−) mice (n=35) or control Apoe−/− mice (n=40) fed a high-cholesterol diet with angiotensin II by implanting osmotic mini-pumps and evaluated the development of AAA. Ninety percent of angiotensin II-infused mice developed AAA, with 50% mortality because of aneurysm rupture. Overexpression of CTLA-4 significantly reduced the incidence (66%), mortality (26%), and diameter (18%) of AAA (incidence: P=0.0104; mortality: P=0.031; diameter: P=0.011). These protective effects were associated with a decreased number of effector CD4+ T cells and the downregulated expression of costimulatory molecules CD80 and CD86, ligands for CTLA-4, on CD11c+ dendritic cells in lymphoid tissues. In addition, by performing in situ zymography of the abdominal aortic aneurysm lesions, we observed a trend toward a decrease in MMP activity in the aneurysmal lesion following overexpression of CTLA-4. Finally, CTLA-4-Tg/Apoe−/− mice had reduced macrophage and CD4+ T cell accumulation and MMP activity in the aneurysmal lesion, leading to attenuated aortic inflammation, preserved vessel integrity, and decreased susceptibility to AAA and aortic rupture.
Conclusion
Our findings suggest that CTLA-4 protects against AAA by suppressing immunoinflammatory responses and could be an attractive therapeutic target for AAA.
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Affiliation(s)
- H Amin
- Faculty of Medicine Universitas Indonesia, Jakarta, Indonesia
| | - N Sasaki
- Kobe Pharmaceutical University, Laboratory of Medical Pharmaceutics, Kobe, Japan
| | - T Yamashita
- Kobe University, Division of Cardiovascular Medicine, Department of Internal Medicine, Kobe, Japan
| | - T Mizoguchi
- Kobe University, Division of Cardiovascular Medicine, Department of Internal Medicine, Kobe, Japan
| | - T Hayashi
- Kobe University, Division of Cardiovascular Medicine, Department of Internal Medicine, Kobe, Japan
| | - T Emoto
- Kobe University, Division of Cardiovascular Medicine, Department of Internal Medicine, Kobe, Japan
| | - T Matsumoto
- Kobe University, Division of Cardiovascular Medicine, Department of Internal Medicine, Kobe, Japan
| | - N Yoshida
- Kobe University, Division of Cardiovascular Medicine, Department of Internal Medicine, Kobe, Japan
| | - T Tabata
- Kobe University, Division of Cardiovascular Medicine, Department of Internal Medicine, Kobe, Japan
| | - S Horibe
- Kobe Pharmaceutical University, Laboratory of Medical Pharmaceutics, Kobe, Japan
| | - S Kawauchi
- Kobe Pharmaceutical University, Laboratory of Medical Pharmaceutics, Kobe, Japan
| | - Y Rikitake
- Kobe Pharmaceutical University, Laboratory of Medical Pharmaceutics, Kobe, Japan
| | - K Hirata
- Kobe University, Division of Cardiovascular Medicine, Department of Internal Medicine, Kobe, Japan
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Oda S, Emoto T, Nakaura T, Kidoh M, Utsunomiya D, Funama Y, Nagayama Y, Takashio S, Ueda M, Yamashita T, Tsujita K, Ando Y, Yamashita Y. Myocardial Late Iodine Enhancement and Extracellular Volume Quantification with Dual-Layer Spectral Detector Dual-Energy Cardiac CT. Radiol Cardiothorac Imaging 2019; 1:e180003. [PMID: 33778497 PMCID: PMC7977749 DOI: 10.1148/ryct.2019180003] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2018] [Revised: 02/01/2019] [Accepted: 02/06/2019] [Indexed: 04/23/2023]
Abstract
PURPOSE To explore the usefulness of myocardial late iodine enhancement (LIE) and extracellular volume (ECV) quantification by using dual-energy cardiac CT. MATERIALS AND METHODS In this single-center retrospective study, a total of 40 patients were evaluated with LIE CT by using a dual-layer spectral detector CT system. Among these, 21 also underwent cardiac MRI. Paired image sets were created by using standard imaging at 120 kVp, virtual monochromatic imaging (VMI) at 50 keV, and iodine density imaging. The contrast-to-noise ratio and image quality were then compared. Two observers assessed the presence of LIE and calculated the interobserver agreements. Agreement between CT and cardiac MRI when detecting late-enhancing lesions and calculating the ECV was also assessed. RESULTS The contrast-to-noise ratio was significantly higher by using VMI than by using standard 120-kVp imaging, and the mean visual image quality score was significantly higher by using VMI than by using either standard or iodine density imaging. For interobserver agreement of visual detection of LIE, the agreement for VMI was excellent and the κ value (κ, 0.87) was higher than that for the standard 120-kVp (κ, 0.70) and iodine density (κ, 0.83) imaging. For detecting late-enhancing lesions, agreement with cardiac MRI was excellent by using VMI (κ, 0.90) and iodine density imaging (κ, 0.87) but was only good by using standard 120-kVp imaging (κ, 0.66). Quantitative comparisons of the ECV calculations by using CT and cardiac MRI showed excellent correlation (r 2 = 0.94). CONCLUSION Dual-energy cardiac CT can assess myocardial LIE and quantify ECV, with results comparable to those obtained by using cardiac MRI.© RSNA, 2019See also the commentary by Litt in this issue.
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Emoto T, Abeyratne UR, Akutagawa M, Konaka S, Kinouchi Y. High frequency region of the snore spectra carry important information on the disease of sleep apnoea. J Med Eng Technol 2011; 35:425-31. [PMID: 22066466 DOI: 10.3109/03091902.2011.626838] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Snoring is the most common symptom of obstructive sleep apnoea (OSA). Several researchers have reported differences between the power spectra of non-OSA and OSA snorers. The traditional approach over the years has been to record snore sounds at a bandwidth of < 5 kHz. Narrowing of the upper airways during OSA events and the resulting upward shift of snore frequencies also lend support to the idea of examining snore sounds beyond 5 kHz. In this paper, we compute the power spectra of snores in three different bands defined as: low-frequency band (LFB: < 5 kHz); middle-frequency band (MFB: 5-10 kHz) and high-frequency band (HFB: 10-20 kHz). We illustrate that there is a significant difference between non-OSA snorers (Apnoea Hypopnoea Index (AHI) < 10) and OSA snorers (AHI > 10) in the region > 5 kHz. We then develop a feature to diagnose OSA based on the spectral differences in the high frequency region and evaluate its performance on a database of 20 subjects. Our results strongly suggest that the high-frequency region of the snore sounds carry information, hitherto disregarded, on the disease of sleep apnoea.
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Affiliation(s)
- T Emoto
- Institute of Technology and Science, The University of Tokushima, Japan.
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Suda T, Wakasugi M, Emoto T, Ishii K, Ito S, Kurita K, Kuwajima A, Noda A, Shirai T, Tamae T, Tongu H, Wang S, Yano Y. First demonstration of electron scattering using a novel target developed for short-lived nuclei. Phys Rev Lett 2009; 102:102501. [PMID: 19392108 DOI: 10.1103/physrevlett.102.102501] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/10/2008] [Indexed: 05/27/2023]
Abstract
We carried out a demonstrative electron scattering experiment using a novel ion-trap target exclusively developed for short-lived highly unstable nuclei. Using stable 133Cs ion as a target, this experiment completely mimicked electron scattering off short-lived nuclei. Achieving a luminosity higher than 10;{26} cm;{-2} s;{-1} with around only 10;{6} trapped ions on the electron beam, the angular distribution of elastic scattering was successfully measured. This experiment clearly demonstrates that electron scattering off rarely produced short-lived nuclei is practical with this target technique.
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Affiliation(s)
- T Suda
- RIKEN Nishina Center, Wako, Saitama 351-0198, Japan
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15
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Wakasugi M, Emoto T, Furukawa Y, Ishii K, Ito S, Koseki T, Kurita K, Kuwajima A, Masuda T, Morikawa A, Nakamura M, Noda A, Ohnishi T, Shirai T, Suda T, Takeda H, Tamae T, Tongu H, Wang S, Yano Y. Novel internal target for electron scattering off unstable nuclei. Phys Rev Lett 2008; 100:164801. [PMID: 18518208 DOI: 10.1103/physrevlett.100.164801] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/09/2007] [Indexed: 05/26/2023]
Abstract
A novel internal target has been developed, which will make electron scattering off short-lived radioactive nuclei possible in an electron storage ring. An "ion trapping" phenomenon in the electron storage ring was successfully utilized for the first time to form the target for electron scattering. Approximately 7 x 10(6) stable 133Cs ions were trapped along the electron beam axis for 85 ms at an electron beam current of 80 mA. The collision luminosity between the stored electrons and trapped Cs ions was determined to be 2.4(8) x 10(25) cm(-2) s(-1) by measuring elastically scattered electrons.
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Affiliation(s)
- M Wakasugi
- RIKEN Nishina Center, Wako, Saitama 351-0198, Japan
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Abstract
Snore sound (SS) is the earliest and the most common symptom of Obstructive Sleep Apnea (OSA) which is a serious disease caused by the collapse of upper airways during sleep. SS should carry vital information on the state of the upper airways and is simple to acquire and rich in features but their analysis is complicated. In this study we use neural network (NN) based method to model SS via a simple second order one-step predictor. We show that the some hidden information/feature of a SS can be conveniently captured in the connection-weight-space (CWS) of the NN, after a process of supervised training. The availability of the proposed method is investigated by performing independent component analysis (ICA) on CWS.
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Affiliation(s)
- T Emoto
- Department of Electrical and Computer Engineering, Takamatsu National College of Technology, Takamatsu, Japan.
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17
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Emoto T, Akutagawa M, Abeyratne UR, Nagashino H, Kinouchi Y. Tracking the states of a nonlinear and nonstationary system in the weight-space of artificial neural networks. Med Biol Eng Comput 2006; 44:146-59. [PMID: 16929933 DOI: 10.1007/s11517-005-0019-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
We propose a novel interpretation and usage of Neural Network (NN) in modeling physiological signals, which are allowed to be nonlinear and/or nonstationary. The method consists of training a NN for the k-step prediction of a physiological signal, and then examining the connection-weight-space (CWS) of the NN to extract information about the signal generator mechanism. We define a novel feature, Normalized Vector Separation (gamma(ij)), to measure the separation of two arbitrary states "i" and "j" in the CWS and use it to track the state changes of the generating system. The performance of the method is examined via synthetic signals and clinical EEG. Synthetic data indicates that gamma(ij) can track the system down to a SNR of 3.5 dB. Clinical data obtained from three patients undergoing carotid endarterectomy of the brain showed that EEG could be modeled (within a root-means-squared-error of 0.01) by the proposed method, and the blood perfusion state of the brain could be monitored via gamma(ij), with small NNs having no more than 21 connection weight altogether.
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Affiliation(s)
- T Emoto
- Faculty of Engineering, The University of Tokushima, Tokushima, Japan.
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18
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Emoto T, Nakamura K, Nagasaka Y, Numa F, Suminami Y, Kato H. Alpha 1-antichymotrypsin inhibits chymotrypsin-induced apoptosis in rat hepatoma cells. Apoptosis 2003; 3:155-60. [PMID: 14646496 DOI: 10.1023/a:1009694621397] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Increased serum levels of alpha1-antichymotrypsin (alpha 1ACT) are observed in some cancer patients, especially those with hepatocellular carcinoma. A possible role of alpha 1ACT in tumour growth has been suggested, but this remains uncertain. We have demonstrated that alpha 1ACT inhibited chymotrypsin-induced apoptosis in rat hepatoma H4 cells. Even low concentrations of chymotrypsin (but not trypsin) induce apoptosis in H4 cells with a minimum effective concentration of 2.4 x 10(-2) units/ml (0.5 microg/ml), and this apoptosis was inhibited by alpha 1ACT in a concentration-dependent manner. Furthermore, the concentrations of alpha 1ACT required to inhibit the apoptosis were lower than normal serum levels. These results may indicate that alpha 1ACT plays a role in the apoptosis of rat hepatoma cells.
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Affiliation(s)
- T Emoto
- First Department of Biochemistry, Yamaguchi University School of Medicine, 1144 Kogushi, Ube 755-8505, Japan.
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19
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Numa F, Umayahara K, Ogata H, Nawata S, Sakaguchi Y, Emoto T, Kawasaki K, Hirakawa H, Sase M, Oga A, Kato H. De novo uterine sarcoma with good response to neo-adjuvant chemotherapy. Int J Gynecol Cancer 2003; 13:364-7. [PMID: 12801270 DOI: 10.1046/j.1525-1438.2003.13185.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
We report here the extremely rare case of a 28-year-old woman with advanced stage uterine sarcoma arising soon after a cesarean section. She underwent an abdominal cesarean section because of a breech presentation. At the time of the procedure, there were no abnormal findings such as leiomyoma of the uterus in the abdominal cavity. One year later, she was referred to our hospital because of a large abdominal tumor. Transabdominal power Doppler ultrasonography and magnetic resonance imaging (MRI) showed a large hypervascular tumor in the abdominal cavity. Her serum levels, for the two tumor markers carbohydrate antigen CA125 and LDH, were elevated, at 219 U/ml (< 35 U/ml) and 862 IU/l (115 U/ml-217 U/ml), respectively. On the basis of a diagnosis of malignant tumor of gynecological origin, exploratory laparotomy was performed, and through biopsy, the tumor was found to be advanced undifferentiated uterine sarcoma. She exhibited a good response to neoadjuvant chemotherapy consisting of cisplatin, epirubicin, and dimethyltriazenoimidazole carboxamide (DTIC) every 28 days, which was successfully followed by a hysterectomy.
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Affiliation(s)
- F Numa
- Departments of Reproductive, Pediatric and Infectious Science, Yamaguchi University School of Medicine, Yamaguchi, Japan.
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20
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Emoto T. [Japanese pharmacopoeia and Dr. Shimizu] (Jpn). Yakushigaku Zasshi 2001; 21:16-8. [PMID: 11621217] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
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21
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Maegawa N, Emoto T, Mori H, Yamaguchi D, Fujinaga T, Tezuka N, Sakai N, Ohtsuka N, Fukuse T. [Two cases of Chlamydia psittaci infection occurring in employees of the same pet shop]. Nihon Kokyuki Gakkai Zasshi 2001; 39:753-7. [PMID: 11828730] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
Abstract
We report here 2 cases of psittacosis in a pet shop. In the first case, a 44-year-old male was admitted with fever, and a chest radiograph showed an infiltration shadow in the right lower lung. One day later, a colleague of the first patient, a 42-year-old man, developed fever and was admitted. In this patient, chest radiography revealed an infiltration shadow in the left lower lung. Both patients had mild liver dysfunction. The serum titer of a complement fixation (CF) test against Chlamydia psittaci was elevated fourfold in the first case and sixteen-fold in the second on the analysis of paired acute- and convalescent-phase serum specimens. Clinical symptoms and abnormal laboratory data were attenuated by the administration of minocycline for 2 weeks. Since both patients worked in same pet shop and since some parakeets at the shop had died, we speculated that the psittacosis had originated from these birds.
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Affiliation(s)
- N Maegawa
- Department of Respiratory Disease, Otsu Red Cross Hospital
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22
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Awaya H, Matsumoto T, Honjo K, Miura G, Emoto T, Matsunaga N. A preliminary study of discrimination among the components of small pulmonary nodules by MR imaging: correlation between MR images and histologic appearance. Radiat Med 2000; 18:29-38. [PMID: 10852653] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
Abstract
PURPOSE To investigate whether magnetic resonance (MR) imaging depicts the internal characteristics of small pulmonary nodules. METHODS We reviewed MR images of 39 surgically resected pulmonary nodules 3 cm or less and compared the components within the nodules. In 22 malignant nodules, eight histologic components were characterized by signal and enhancement patterns on MR images. RESULTS MR images obtained from any single sequence discriminated all components in 26 (67%) nodules, whereas the combination of images from various sequences allowed discrimination in 35 (90%). Fourteen of 16 components of aggregated tumor cells showed marked early enhancement. Although fibrotic and necrotic components showed no or slight early enhancement, nine of 10 fibrotic components showed hypointensity and six of seven necrotic components showed hyperintensity on T2-weighted images. Component characterization in eight histologies by MR imaging was possible in 71-100%. CONCLUSION Our study demonstrated that MR imaging offers the possibility of high tissue-contrast resolution in small pulmonary nodules.
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Affiliation(s)
- H Awaya
- Department of Radiology, Yamaguchi University School of Medicine, Ube, Japan
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23
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Nishihata Y, Emura S, Maeda H, Kubozono Y, Harada M, Uruga T, Tanida H, Yoneda Y, Mizuki J, Emoto T. XAFS spectra in the high-energy region measured at SPring-8. J Synchrotron Radiat 1999; 6:149-151. [PMID: 15263229 DOI: 10.1107/s0909049598016781] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/1998] [Accepted: 12/07/1998] [Indexed: 05/24/2023]
Affiliation(s)
- Y Nishihata
- Japan Atomic Energy Research Institute, Sayo-gun, Hyogo, Japan.
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24
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Emoto T, Akimoto K, Ichimiya A. Observation of the strain field near the Si(111) 7 x 7 surface with a new X-ray diffraction technique. J Synchrotron Radiat 1998; 5:964-966. [PMID: 15263712 DOI: 10.1107/s0909049597017792] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/04/1997] [Accepted: 11/24/1997] [Indexed: 05/24/2023]
Abstract
A new X-ray diffraction technique has been developed in order to measure the strain field near a solid surface under ultrahigh vacuum (UHV) conditions. The X-ray optics use an extremely asymmetric Bragg-case bulk reflection. The glancing angle of the X-rays can be set near the critical angle of total reflection by tuning the X-ray energy. Using this technique, rocking curves for Si surfaces with different surface structures, i.e. a native oxide surface, a slightly oxide surface and an Si(111) 7 x 7 surface, were measured. It was found that the widths of the rocking curves depend on the surface structures. This technique is efficient in distinguishing the strain field corresponding to each surface structure.
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Affiliation(s)
- T Emoto
- Department of Quantum Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-01, Japan
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25
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Sato S, Okabe M, Emoto T, Kurasaki M, Kojima Y. Restriction of cadmium transfer to eggs from laying hens exposed to cadmium. J Toxicol Environ Health 1997; 51:15-22. [PMID: 9169058 DOI: 10.1080/00984109708984008] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The transfer of Cd to eggs of white Leghorn laying hens has been shown to be restricted. After Cd was injected ip into laying hens, the Cd concentrations in the blood, livers, ovaries, and eggs were measured. Although the Cd concentrations in the maternal blood and livers increased remarkably at certain levels of administrations, the Cd concentration in the yolks of eggs was not significantly increased, and was less than 0.04 microgram/g wet weight. After egg production stopped in the highest injected group (7.5 mg Cd/kg), Cd in the yolks of eggs had an accumulated range of 0.02-0.03 microgram/g wet weight. This was despite the high Cd accumulation in the liver. Furthermore, the Cd concentration in the follicle walls of the ovary increased and was 13- to 52-fold higher than in the follicle yolks. An additional experiment was conducted in order to estimate whether hatching success is affected by the Cd in the laid eggs of Cd-injected laying hens. The ratio of hatching success in the 0.3 or 1.2 micrograms Cd/egg-injected groups was similar to that in the saline-injected group, indicating that a small amount of Cd in the eggs might exert no marked influence on the hatching success. In conclusion, Cd transfer from laying hen to eggs was restricted after the maternal bird was exposed to Cd. Furthermore, Cd accumulates in the follicle walls of ovary. These results suggest that the follicle walls might play a role in protecting the follicle yolks against Cd toxicity.
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Affiliation(s)
- S Sato
- Department of Environmental Medicine and Informatics, Graduate School of Environmental Earth Science, Hokkaido University, Sapporo, Japan
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26
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Yamasaki F, Kurasaki M, Oikawa S, Emoto T, Okabe M, Kojima Y. Effects of amino acid replacements on cadmium binding of metallothionein alpha-fragment. Cell Mol Life Sci 1997; 53:459-65. [PMID: 9176566 DOI: 10.1007/s000180050056] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
To evaluate whether only 20 cysteine residues at invariant positions are needed to bind and coordinate the metals in metallothioneins (MTs), and whether changing the positions of cysteine residues in the sequence affects the metal-binding capacity and the coordination of MTs, we examined the cadmium-binding affinities of seven mutant MT alpha s using an Escherichia coli expression system. Five mutant MT alpha s in which the constitutive amino acid residues other than cysteines of the alpha-fragment were replaced with glycine residues, and the remaining two mutant MT alpha s in which the invariant positions of the cysteine residues of the alpha-fragment were shifted, were analysed for their ability to be expressed as cadmium-binding forms and for their biochemical properties. The results showed that extreme alteration of the constitutive amino acid residues other than cysteines in the MT alpha-fragment leads to disruption of their cadmium-binding abilities and of their structure. However, mutant MT alpha s containing changes of the invariant positions of the cysteine residues were expressed in a cadmium-binding form in Escherichia coli, although the invariant positions of 20 cysteine residues in the MTs are thought to be important for their metal-binding abilities. These results suggest that the position of cysteine residues and the chemical nature of the other amino acids in the amino acid sequence of MTs are less critical than expected.
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Affiliation(s)
- F Yamasaki
- Department of Environmental Medicine and Informatics, Graduate School of Environmental Earth Science, Hokkaido University, Sapporo, Japan.
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27
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Narita M, Nakao K, Ogino N, Emoto T, Nakahara M, Yumiba T, Tsujimoto M. A Case of Microangiopathic Hemolytic Anemia Associated with Breast Cancer: Improvement with Chemoendocrine Therapy. Breast Cancer 1997; 4:39-42. [PMID: 11091575 DOI: 10.1007/bf02967054] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Microangiopathic hemolytic anemia (MAHA) is a term which describes the association of hemolytic anemia with red cell fragmentation caused by microangiopathy mechanically. This paper reports a 45-year-old woman with bone metastases from breast cancer. She developed MAHA and disseminated intravascular coagulation (DIC). Although the prognosis of MAHA associated with malignant tumor has been very poor, she achieved remission of the syndrome after chemoendocrine therapy.
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Affiliation(s)
- M Narita
- Departments of Surgery, Osaka Police Hospital, 10-31 Kitayama-cho, Tennouji-ku, Osaka 543, Japan
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28
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Emoto T, Miyata M, Izukura M, Yumiba T, Mizutani S, Sakamoto T, Matsuda H. Simultaneous observation of endocrine and exocrine functions of the pancreas responding to somatostatin in man. Regul Pept 1997; 68:1-8. [PMID: 9094748 DOI: 10.1016/s0167-0115(96)00125-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Six patients who underwent segmental autotransplantation of the caudal pancreas (SAT) following total pancreatectomy for pancreatic cancer were investigated. The graft was transplanted to the left groin, and pancreatic juice was diverted outside through a polyethylene tube indwelled into the main pancreatic duct. In these SAT patients, the responses of insulin (IRIS) in terms of plasma levels and pancreatic secretion to subcutaneous injections of somatostatin octreotide (Sandostatin: SMS201-995) were simultaneously observed. Four doses (0.039, 0.156, 0.625 and 2.5 micrograms/kg) of SMS201-995 were given on separate days. As a control, saline was injected subcutaneously. Standard liquid test meal was given 1 h after the subcutaneous injection. The basal plasma IRI were significantly decreased with doses greater than 0.156 microgram/kg. The postprandial responses of IRI was also significantly suppressed with the same doses. On the other hand, the basal pancreatic exocrine secretion was significantly suppressed with doses greater than 0.625 microgram/kg. The postprandial pancreatic exocrine secretion was also significantly suppressed with doses greater than 0.625 microgram/kg. Those suppressions were dose-dependent. The postprandial CCK secretion was also significantly suppressed in dose-dependent manner with SMS201-995. The CCK suppression was significantly correlated with the suppression of pancreatic exocrine secretion. This clinical study under the setting of SAT demonstrated not only the direct inhibitory effect of somatostatin on both the islet and acinar cells but also, probably, the indirect inhibitory effect on the acinal cells via suppression of CCK release in humans.
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Affiliation(s)
- T Emoto
- First Department of Surgery, Osaka University Medical School, Suita, Japan
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29
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Kurasaki M, Emoto T, Arias AR, Okabe M, Yamasaki F, Oikawa S, Kojima Y. Independent self-assembly of cadmium-binding alpha-fragment of metallothionein in Escherichia coli without participation of beta-fragment. Protein Eng 1996; 9:1173-80. [PMID: 9010930 DOI: 10.1093/protein/9.12.1173] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
We examined the independent self-assembly of the alpha- and beta-fragments of human metallothionein (MT) into cadmium-binding conformation in an Escherichia coli expression system, in addition to wild-type MT expression. The expressed alpha-fragment formed independently the structure of a metal-binding cluster without the aid of the beta-fragment. The alpha-fragment and wild-type MT expressed in E.coli were purified and analyzed for their biochemical and spectroscopic properties. The apparent cadmium binding of the alpha-fragment was approximately 12-fold greater than that for the wild-type MT, whereas in other respects the studied biochemical properties were similar. In contrast, we were unable to obtain any independently expressed beta-fragment as the cadmium-binding form in this study. Possible explanations for this phenomenon are discussed.
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Affiliation(s)
- M Kurasaki
- Department of Environmental Medicine and Informatics, Graduate School of Environmental Earth Science, Hokkaido University, Sapporo, Japan
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30
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Emoto T, Kurasaki M, Oikawa S, Suzuki-Kurasaki M, Okabe M, Yamasaki F, Kojima Y. Roles of the conserved serines of metallothionein in cadmium binding. Biochem Genet 1996; 34:239-51. [PMID: 8813055 DOI: 10.1007/bf02407022] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The sequence of six amino acid residues -Ser-Cys-Cys-Ser-Cys-Cys- is present in all mammalian metallothionein sequences and has been highly conserved during evolution, although the metallothioneins have divergent primary sequences. To determine whether two serines in the sequence play a crucial role in metal-binding of metallothioneins, a mutant metallothionein with these two serines replaced by leucines was obtained using an Escherichia coli expression system. The expressed protein was analyzed for its chemical and spectroscopic properties. It was confirmed that the mutant metallothionein (MT) bound cadmium through a metal-thiolate complex and that there was no strong difference between the mutant and the wild-type MTs in retaining the metal-binding cluster. However, the metal-binding cluster of the mutant metallothionein was more unstable than that of the wild-type metallothionein. The two conservative serines could play a role in the stability of metal-binding ligands.
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Affiliation(s)
- T Emoto
- Department of Environmental Medicine and Informatics, Graduate School of Environmental Earth Science, Hokkaido University, Sapporo, Japan
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31
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Odawara F, Kurasaki M, Suzuki-Kurasaki M, Oikawa S, Emoto T, Yamasaki F, Linde Arias AR, Kojima Y. Expression of human metallothionein-2 in Escherichia coli: cadmium tolerance of transformed cells. J Biochem 1995; 118:1131-7. [PMID: 8720126 DOI: 10.1093/oxfordjournals.jbchem.a124998] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
A genetic approach was undertaken to investigate the physiological roles of human metallothionein-2. A constructed expression plasmid, pEXPMTII, in which human metallothionein-IIA cDNA was inserted downstream of a tryptophan-lactose promoter, was used to transform Escherichia coli JM105 strain. Cadmium-binding metallothionein was successfully expressed in E. coli in the medium containing cadmium, while copper and zinc-metallothioneins were scarcely observed in copper- or zinc-containing medium. The amino acid composition and sequence of the biosynthesized cadmium-metallothionein were analyzed. The selectivity of metals bound to metallothionein and the stability of metal-binding forms of metallothionein in E. coli were discussed. In addition, cadmium, zinc, or copper resistance of the cells expressing metallothionein was examined. Cells transformed with the plasmid pEXPMTII and cultured in a medium containing cadmium exhibited tolerance only to cadmium. It was demonstrated that human metallothionein-2 functioned for cadmium detoxification in E. coli.
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Affiliation(s)
- F Odawara
- Department of Environmental Medicine and Informatics, Hokkaido University, Sapporo
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Abstract
A somatostatin analog (SMS201-995) was administered subcutaneously to six totally pancreatectomized (TP) patients at five dose levels from 0 microgram/kg (control) to 2.5 micrograms/kg before ingestion of a liquid test meal, and plasma levels of neurotensin (NT) were measured. There were no significant differences in basal levels of NT between the doses of somatostatin. The NT levels were significantly elevated after ingestion of the test meal in the normal controls (n = 14). In the TP patients postprandial hypersecretion of NT was observed. The hypersecretion of NT in the patients was suppressed by SMS201-995 dose-dependently.
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Affiliation(s)
- T Sakamoto
- First Department of Surgery, Osaka University Medical School, Japan
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Kasai K, Yamaguchi F, Hosoya T, Ichimura K, Banba N, Emoto T, Hiraiwa M, Hishinuma A, Hattori Y, Shimoda S. Effects of inorganic iodide, epidermal growth factor and phorbol ester on hormone synthesis by porcine thyroid follicles cultured in suspension. Life Sci 1992; 51:1095-103. [PMID: 1518372 DOI: 10.1016/0024-3205(92)90510-v] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Porcine thyroid follicles cultured in suspension for 96 h synthesized and secreted thyroid hormones in the presence of thyrotropin (TSH). The secretion of newly synthesized hormones was assessed by determining the contents of thyroxine (T4) and triiodothyronine (T3) in the media and by paperchromatographic analysis of 125I-labelled hormones in the media where the follicles were cultured in the presence and absence of inhibitors of hormone synthesis. The hormone synthesis and secretion was modified by exogenously added NaI (0.1-100 microM). The maximal response was obtained at 1 microM. Thyroid peroxidase (TPO) activity in the cultured follicles with TSH for 96 h was dose-dependently inhibited by NaI. One hundred microM of NaI completely inhibited TSH-induced TPO activity. Moreover, both epidermal growth factor (EGF: 10(-9) and 10(-8) M) and phorbol 12-myristate 13-acetate (PMA: 10(-8) and 10(-7) M) inhibited de novo hormone synthesis. An induction of TPO activity by TSH was also inhibited by either agent. These data provide direct evidences that thyroid hormone synthesis is regulated by NaI as well as TSH at least in part via regulation of TPO activity and also that both EGF and PMA are inhibitory on thyroid hormone formation.
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Affiliation(s)
- K Kasai
- Department of Endocrinology, Dokkyo University School of Medicine, Tochigi, Japan
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35
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Hishinuma A, Kasai K, Ichimura K, Emoto T, Shimoda S. Effects of epidermal growth factor, phorbol ester, and retinoic acid on hormone synthesis and morphology in porcine thyroid follicles cultured in collagen gel. Thyroid 1992; 2:351-9. [PMID: 1493378 DOI: 10.1089/thy.1992.2.351] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Epidermal growth factor (EGF), phorbol esters (PEs), and retinoic acid (RA) inhibit differentiated functions of thyrocytes. In the present study the inhibitory effects of these growth-promoting factors on hormone synthesis were studied in thyroid follicles cultured in type-I collagen gel, and morphologic alteration by these factors was examined by light and electron microscopy (EM). Porcine open thyroid follicles obtained by treatment with 0.1% collagenase were embedded in collagen gel and cultured in Ham's F12 medium supplemented with 6H (insulin, hydrocortisone, somatostatin, transferrin, glycyl-his-lys, and thyrotropin) + 0.5% fetal bovine serum (FBS). After 1 week these open follicles developed to closed follicles, and the medium was changed to one containing 6H + 0.5% FBS + 0.1 microM sodium iodide (NaI). Some media were supplemented with either EGF, phorbol 12-myristate 13-acetate (PMA), or all-trans RA. The closed follicles retained ability for hormone synthesis for 2 weeks after the medium change in the presence of 6H + FBS + NaI. The amounts of T4 and T3 secreted into the culture medium from day 9 to day 12 after the medium change were 60% and 45% of those from day 0 to day 4, respectively. EGF reduced production of T4 and T3 by 61% and 69%, respectively; PMA, by 87% and 99%; and RA, by 55% and 44%. In the medium supplemented with 6H + 0.5% FBS, the follicles exhibited intact polarity. Apical surfaces with microvilli were oriented to the follicular lumen and tight junctions were on the apical side of cell-to-cell contacts. Desmosomes were found on both the apical and basal halves of the cell contacts.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- A Hishinuma
- Department of Endocrinology, Dokkyo University School of Medicine, Tochigi, Japan
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36
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Nakamura T, Kasai K, Sekiguchi Y, Banba N, Takahashi K, Emoto T, Hattori Y, Shimoda S. Elevation of plasma endothelin concentrations during endotoxin shock in dogs. Eur J Pharmacol 1991; 205:277-82. [PMID: 1667911 DOI: 10.1016/0014-2999(91)90910-i] [Citation(s) in RCA: 55] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The effect of endotoxin on the release of endothelin, a novel potent vasoconstrictor peptide, was examined in anesthetized dogs and in cultured endothelial cells. Administration of 2.63 mg lipopolysaccharide, E. coli 0111:B4/kg body weight caused shock in the animals and produced a long-lasting increase in the plasma immunoreactive endothelin-1 level that remained higher than the basal level (1.83 pg/ml as mean level) from 30 to 120 min after the injection, with a peak at 90 min (8.15 pg/ml as mean level). In vitro immunoreactive endothelin-1 in a culture medium, in which calf pulmonary artery endothelial cells were incubated in the presence of 10% fetal bovine serum, increased dose dependently with the concentration of added lipopolysaccharide between 0.01 and 10 micrograms/ml. These data indicate that plasma endothelin increases during endotoxin shock and that stimulation by endotoxin, per se, in the presence of serum participates at least partially in the mechanism for its release.
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Affiliation(s)
- T Nakamura
- Department of Endocrinology, Dokkyo University School of Medicine, Tochigi, Japan
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37
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Li Y, Togashi Y, Sato S, Emoto T, Kang JH, Takeichi N, Kobayashi H, Kojima Y, Une Y, Uchino J. Spontaneous hepatic copper accumulation in Long-Evans Cinnamon rats with hereditary hepatitis. A model of Wilson's disease. J Clin Invest 1991; 87:1858-61. [PMID: 2022751 PMCID: PMC295311 DOI: 10.1172/jci115208] [Citation(s) in RCA: 221] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Long-Evans Cinnamon (LEC) rats, an inbred strain of a mutant rat isolated from Long-Evans rats, develop hereditary hepatitis. To elucidate the role of copper metabolism in the development of the hepatitis in LEC rats, we examined the copper concentration in the tissues and serum levels of copper and ceruloplasmin. Copper concentration in the liver of LEC rats was over 40 times that of normal Long-Evans Agouti (LEA) rats, while the serum ceruloplasmin and copper concentrations in LEC rats decreased significantly. The hepatocytes of LEC rats show steatosis in cytoplasm and pleomorphism of mitochondria, resembling the histologic features of the liver in Wilson's disease. These findings suggest that the hereditary hepatitis in LEC rats is closely associated with copper toxicity, and may be dealing with a rat form of Wilson's disease. Thus the LEC rats will provide a unique and useful animal model for clarifying the mechanism and for developing treatment strategies for Wilson's disease and other abnormal copper metabolism in humans.
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Affiliation(s)
- Y Li
- Laboratory of Pathology, Cancer Institute, Hokkaido University School of Medicine, Sapporo, Japan
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38
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Li Y, Togashi Y, Sato S, Emoto T, Kang JH, Takeichi N, Kobayashi H, Kojima Y, Une Y, Uchino J. Abnormal copper accumulation in non-cancerous and cancerous liver tissues of LEC rats developing hereditary hepatitis and spontaneous hepatoma. Jpn J Cancer Res 1991; 82:490-2. [PMID: 1905694 PMCID: PMC5918487 DOI: 10.1111/j.1349-7006.1991.tb01876.x] [Citation(s) in RCA: 48] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
We studied the copper concentrations in the non-cancerous and cancerous liver tissues of LEC rats with hereditary hepatitis and spontaneous hepatoma by atomic absorption spectrophotometry. Copper concentration in the non-cancerous livers of 29-month-old male LEC rats was comparable to that in the livers of LEC rats aged 2, 3 and 8 months whose hepatic copper concentrations were more than 40 times those of normal LEA rats. Copper concentration in spontaneously developed hepatocellular carcinomas of the 29-month-old male LEC rats was lower than that in the surrounding non-cancerous liver tissues, but was still more than 39 times that of 8-month-old male LEA rats. These findings suggest that in LEC rats an abnormal copper metabolism may be maintained during the process of hepatic carcinogenesis.
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Affiliation(s)
- Y Li
- Laboratory of Pathology, Cancer Institute, Hokkaido University School of Medicine, Sapporo
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39
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Abstract
We measured the release of immunoreactive endothelin-1 (IR-ET-1) by cultured porcine aortic endothelial cells under normoglycemic (5.5 mmol/L) and hyperglycemic (27.5 and 55 mmol/L) conditions. Compared with cells incubated in the presence of a normal glucose concentration, cells incubated in 27.5 mmol/L glucose medium released 52% less IR-ET-1, and those incubated in 55 mmol/L glucose medium released 54% less IR-ET-1. The observed effects of elevated glucose on IR-ET-1 release were both sugar-specific and not due to increased osmolarity. Fetal calf serum (FCS)-stimulated IR-ET-1 release in the presence of elevated glucose was also less than that in the presence of a normal glucose concentration. In addition, the effects of two hormones, insulin and insulin-like growth factor 1 (IGF-1), on IR-ET-1 release were examined. Both insulin and IGF-1 dose-dependently stimulated IR-ET-1 release. Twenty micrograms/mL insulin and 10(-8) mol/L IGF-1 increased IR-ET-1 release by 38% and by 44%, respectively. These results indicate that hyperglycemic condition results in reduction of IR-ET-1 release from cultured porcine aortic endothelial cells and that insulin and IGF-1 stimulate its release. The possible relevance of these observations to physiological regulation of ET-1 release in vivo and pathological processes in diabetes remains to be established.
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Affiliation(s)
- Y Hattori
- Department of Endocrinology, Dokkyo University School of Medicine, Tochigi, Japan
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40
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Yoshikawa K, Iwasaki T, Amemiya A, Emoto T, Fujii M, Han N, Itou A, Tsujimura T. [Tissue UFT distribution and histological changes following UFT administration in metastatic liver cancer cases]. Gan To Kagaku Ryoho 1990; 17:1333-7. [PMID: 2114828] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
For the purpose of assessing the anti-tumor effect of UFT in metastatic liver cancer, blood futraful (FT), 5-fluorouracil (5-FU) and uracil levels and their distribution in tissue (cancer lesion, etc.) following oral UFT administration were examined in 10 surgically treated cases of metastatic liver cancer secondary to cancer of the large intestine and 4 cases of metastatic liver cancer secondary to stomach cancer. Liver tissue 5-FU distribution following UFT treatment was excellent. 5-FU concentration in liver cancer lesion was 0.164 +/- 0.128 micrograms/g, which was markedly higher than the minimal effective tissue concentration for 5-FU (0.050 micrograms/g). 5-FU level in normal tissue of the organ with primary cancer was significantly lower than that in the tumor-affected tissue of the same organ, while no difference in 5-FU level was noted between cancer-affected and normal tissues of the liver. Tissue 5-FU level in both primary and metastatic cancer lesions was significantly higher than the simultaneously determined blood 5-FU level. Histological findings of cancer-affected liver did not differ between different UFT dose levels, but degeneration of cancer cells was severe in some cases given high doses of UFT.
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41
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Kasai K, Emoto T, Hiraiwa M, Kuroda H, Yamazaki A, Hattori Y, Shimoda S. Inhibition by protein kinase-C inhibitor and cycloheximide of phorbol ester- and epidermal growth factor-induced arachidonic acid metabolism in cultured porcine thyroid cells. Metabolism 1990; 39:709-13. [PMID: 2114514 DOI: 10.1016/0026-0495(90)90105-l] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
In an attempt to elucidate possible mechanism(s) for stimulated arachidonic acid metabolism by phorbol 12-myristate 13-acetate (PMA) and epidermal growth factor (EGF) in porcine thyroid cells, we examined the effects of protein kinase inhibitors, isoquinolinesulfonamide derivatives (H-7 and HA-1004), and cycloheximide. The production of PGE2 stimulated by either PMA or EGF was strongly inhibited by H-7, with an ID50 value of approximately 20 to 25 mumol/L in each case, as well as by cycloheximide, with an ID50 value of less than 0.5 micrograms/mL in each case. In contrast, 100 mumol/L of HA-1004 showed less inhibition of PGE2 production provocated by either PMA or EGF. On the other hand, PGE2 production in basal or stimulated condition by exogenously added arachidonic acid, was inhibited to an even lesser extent by both H-7 and cycloheximide. The EGF- and PMA-stimulated release of 3H-arachidonic acid from the cells was also strongly inhibited by H-7 and cycloheximide. These results suggest an induction of synthesis of some proteins responsible for the release of arachidonic acid, which might be attributed to protein kinase-C activation in arachidonic acid metabolism stimulated by PMA or EGF. Moreover, PGE2 production was potently induced by PMA and slightly by EGF in the cyclooxygenase-inactivated cells by acetyl salicylate pretreatment, which also suggests that both agents might induce the synthesis of cyclooxygenase in cultured porcine thyroid cells, although we did not measure its activity.
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Affiliation(s)
- K Kasai
- Department of Endocrinology, Dokkyo University School of Medicine, Tochigi, Japan
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42
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Miyata M, Kitagawa T, Emoto T, Dousei T, Izukura M, Tanaka Y, Kawashima Y. Role of heterotopically transplanted segmental pancreas in glucose homeostasis in humans. Transplant Proc 1990; 22:604-6. [PMID: 2183427] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Affiliation(s)
- M Miyata
- First Department of Surgery, Osaka University Medical School, Japan
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43
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Kasai K, Hiraiwa M, Emoto T, Kuroda H, Hattori Y, Mochizuki Y, Nakamura T, Shimoda S. Presence of high affinity receptor for interleukin-1 (IL-1) on cultured porcine thyroid cells. Horm Metab Res 1990; 22:75-9. [PMID: 2138997 DOI: 10.1055/s-2007-1004855] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Using 125I-interleukin-1 beta (125I-IL-1 beta) as a ligand, a specific receptor of high affinity dissociation constant (1.1 +/- 0.2 x 10(-10) M) with binding sites (350 +/- 40/cell) for interleukin-1 beta (IL-1 beta) has been demonstrated on cultured porcine thyroid cells. IL-1 alpha almost equally cross-reacted with the receptor (Kd = 1.2 +/- 0.3 x 10(-10) M and 350 +/- 50 binding sites/cell). TSH, IL-2 and other peptide hormones did not inhibit the binding of 125I-IL-1 beta to thyroid cells. Crosslinking study revealed a major band (approximately 95 kD) with a corrected molecular mass of approximately 78 kD. Moreover, both IL-1 beta and IL-1 alpha stimulated prostaglandin E2 production of cultured porcine thyroid cells, although the potency of IL-1 alpha was slightly greater than that of IL-1 beta. These results suggest that IL-1 may be involved in the regulation of thyroid cell function.
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Affiliation(s)
- K Kasai
- Department of Endocrinology, Internal Medicine, Dokkyo University School of Medicine, Tochigi, Japan
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44
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Yoshikawa K, Mikata S, Inoue M, Amemiya A, Iwasaki T, Moriguchi S, Emoto T, Han N, Itou A. [Hepatocellular carcinoma with extrahepatic malignancies]. Gan No Rinsho 1990; 36:23-8. [PMID: 1688958] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
A clinical investigation of 16 hepatocellular carcinoma (HCC) patients with extrahepatic malignancies (13 male, 3 female) has been conducted. The age of these patients ranged from 55 to 76 years. Three of these double cancer cases were hemocronous, and 13 were heterochronous. The duration between the occurrence of the cancers ranged from 2 years and 4 months to 22 years. As for the site of the other cancer, the stomach was the most common organ (12 cases). In nine cases out of 16, the HCC was resected, whereas the other cases were treated with a TAE and hepatic artery ligation because the cancer were far advanced stages. Early detection of an HCC by AFP or an ultrasonographic examination, and a subsequent surgical resection in cases of a postoperative cancer patient with a liver dysfunction may lead to a more favorable prognosis.
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45
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Abstract
Immunoreactive-endothelin (ir-ET) concentrations were determined in peripheral maternal blood and in umbilical cord blood just after delivery. The concentrations in both the umbilical artery (2.83 +/- 1.36 pmol/l plasma, Mean +/- SD) and vein (3.37 +/- 1.53 pmol/l) were significantly higher than those found in maternal venous blood (1.43 +/- 1.02 pmol/l). On the other hand, ir-ET levels in maternal blood were not significantly different when compared with those found in non-pregnant women (1.50 +/- 0.83 pmol/l). No significant difference of ir-ET levels between the umbilical artery and vein was observed. A highly significant correlation (r = 0.60, p less than 0.01) of ir-ET levels between the umbilical artery and vein was observed. Also, a significant correlation (r = 0.48, p less than 0.01) between umbilical vein and maternal vein ir-ET levels with a weaker correlation (r = 0.36, p less than 0.05) between umbilical artery and maternal vein ir-ET levels was demonstrated. The present study indicates that ir-ET may be actively secreted in fetal circulation and the plasma levels in maternal and fetal circulation may have a possible relation.
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Affiliation(s)
- T Nakamura
- Department of Endocrinology, Dokkyo University School of Medicine, Tochigi, Japan
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46
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Hattori Y, Kasai K, Emoto T, Hiraiwa M, Shimoda S. The inhibitory effect of cyclosporine on prostacyclin production by cultured endothelial cells from porcine aorta. Transplant Proc 1989; 21:3461-3. [PMID: 2662489] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Affiliation(s)
- Y Hattori
- Department of Endocrinology, Dokkyo University School of Medicine, Tochigi, Japan
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47
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Kasai K, Ohmori T, Koizumi N, Hosoya T, Hiraiwa M, Emoto T, Hattori Y, Shimoda S. Regulation of thyroid peroxidase activity by thyrotropin, epidermal growth factor and phorbol ester in porcine thyroid follicles cultured in suspension. Life Sci 1989; 45:1451-9. [PMID: 2811602 DOI: 10.1016/0024-3205(89)90035-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
The activity of thyroid peroxidase (TPO) in porcine follicles cultured for 96 h in suspension with five hormones (5H) still attained over 50% of that in the freshly isolated follicles. On the other hand, the activity in those cultured with 5H + TSH (6H) was several times higher than that cultured with 5H after 96 h, although an initial decrease of TPO activity during the first 24 h of culture was observed in both conditions. The ability of follicles to metabolize iodide (uptake and organification) when cultured with 6H for 96 h was also several times higher than that of those cultured with 5H. The half-maximal dose of TSH for stimulation of TPO activity and iodide metabolism was 0.03-0.04 mU/ml and the effect was mediated by cAMP. These results indicate that in porcine thyroid follicles in primary suspension culture, TPO activity as well as the ability of iodide metabolism is induced by chronic TSH stimulation. In addition, epidermal growth factor (EGF, 10(-9)M) and phorbol 12-myristate 13-acetate (PMA, 10(-8) M) completely inhibited TSH stimulation on both activities and also basal (5H) activity of iodide metabolism.
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Affiliation(s)
- K Kasai
- Department of Endocrinology, Dokkyo University School of Medicine, Tochigi, Japan
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48
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Abstract
The left-most 3.9 kb of adenovirus type 40 (Ad40) DNA has been sequenced using cloned viral DNA fragments. The Ad40 E1 region is deduced to code for at least four polypeptides, 221 and 249 amino acids as E1A products in addition to 166 and 475 amino acids as E1B products. E1B polypeptides share about 50% homology with well-defined adenovirus types, 2/5, 7, and 12, throughout the E1B sequences. E1A homology of Ad40 to these types is relatively lower than that of E1B, while highly conserved regions of E1A are retained to a certain level in Ad40 as well. Activity for morphological transformation of Ad40 E1A on 3Y1 cells is considerably lower when compared to that of Ad5 and Ad12 E1A genes. Transient chloramphenicol acetyltransferase (CAT) expression assay shows that Ad40 E1A has a trans-acting function, though lower than that of other E1A genes, on adenovirus early promoter. The Ad40 E1A promoter also holds only a little cis-acting activity in 3Y1 cells. Lower activities of both Ad40 E1A promoter and certain E1A functions may explain in part the difficulty in propagation of Ad40.
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Affiliation(s)
- M Ishino
- Cancer Research Institute, Sapporo Medical College, Japan
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49
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Abstract
In cultured porcine thyroid cells, during 60 min incubation phorbol 12-myristate 13-acetate (PMA) had no effect on basal cyclic AMP accumulation and slightly stimulated cyclic AMP accumulation evoked by thyroid stimulating hormone (TSH) or forskolin. Cholera toxin-induced cyclic AMP accumulation was significantly stimulated by PMA. On the other hand, cyclic AMP accumulation evoked by prostaglandin E1 or E2 (PGE1 or PGE2) was markedly depressed by simultaneous addition of PMA. These opposing effects of PMA on cyclic AMP accumulation evoked by PGE and cholera toxin were observed in a dose-related fashion, with half-maximal effect of around 10(-9) M in either case. The almost same effects of PMA on cyclic AMP accumulation in basal and stimulated conditions were also observed in freshly prepared thyroid cells. The present study was performed in the presence of phosphodiesterase inhibitor, 3-iso-butyl-1-methylxanthine (IBMX), indicating that PMA affected adenylate cyclase activity. Therefore, it is suggested that PMA may modulate the production of cyclic AMP in response to different stimuli, possibly by affecting several sites in the adenylate cyclase complex in thyroid cells.
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Affiliation(s)
- T Emoto
- Department of Endocrinology, Internal Medicine, Dokkyo University School of Medicine, Tochigi, Japan
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50
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Kasai K, Hiraiwa M, Emoto T, Akimoto K, Takaoka T, Shimoda S. Stimulation of prostaglandin E2 production by phorbol esters and epidermal growth factor in porcine thyroid cells. Life Sci 1987; 41:241-7. [PMID: 3110525 DOI: 10.1016/0024-3205(87)90499-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Effects of phorbol esters and epidermal growth factor (EGF) on prostaglandin E2 production by cultured porcine thyroid cells were examined. Both phorbol 12-myristate 13-acetate (PMA) and EGF stimulated prostaglandin E2 production by the cells in dose related fashion. PMA stimulated prostaglandin E2 production over fifty-fold with the dose of 10(-7) M compared with control. EGF (10(-7) M) also stimulated it about ten-fold. The ED50 values of PMA and EGF were respectively around 1 X 10(-9) M and 5 X 10(-10) M. Thyroid stimulating hormone (TSH), however, did not stimulate prostaglandin E2 production from 1 to 24-h incubation. The release of radioactivity from [3H]-arachidonic acid prelabeled cells was also stimulated by PMA and EGF, but not by TSH. These results indicate that both PMA and EGF are potent stimulators of prostaglandin E2 production, associated with the activity to stimulate arachidonic acid release in porcine thyroid cells.
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