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Maezawa M, Inoue M, Satake R, Wakabayashi W, Oura K, Goto F, Miyasaka K, Hirofuji S, Iwata M, Suzuki T, Tanaka H, Nishida S, Shimizu S, Suzuki A, Iguchi K, Nakamura M. Effect of acid suppressant medications on the laxative action of magnesium preparations in patients with opioid-induced constipation: A pharmacovigilance analysis of the FDA Adverse Event Reporting System. Pharmazie 2023; 78:245-250. [PMID: 38178284 DOI: 10.1691/ph.2023.3624] [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: 01/06/2024]
Abstract
Objective: Magnesium oxide is widely used for treating opioid-induced constipation, a serious analgesic-associated problem. Opioid analgesic users are often prescribed non-steroidal anti-inflammatory drugs, which are sometimes combined with acid suppressants to prevent gastrointestinal adverse events. Magnesium preparations combined with acid suppressants may diminish magnesium preparations' laxative effect. This study was aimed at evaluating the effect of magnesium preparations combined with acid suppressants on the incidence of opioid-induced constipation by using the Food and Drug Administration Adverse Event Reporting System. Methods: Adverse events were defined per the Medical Dictionary for Regulatory Activities; the term 'constipation (preferred term code: 10010774)' was used for analysis. After adjusting for patient background factors using propensity score matching, acid suppressants' effect on constipation incidence was evaluated in opioid users prescribed magnesium preparations alone as laxatives by using a test for independence. Key Findings: The Food and Drug Administration Adverse Event Reporting System contains 14,475,614 reports for January 2004 to December 2021. Significantly increased constipation incidence was related to magnesium preparations combined with acid suppressants, especially proton pump inhibitors (P < 0.0001, McNemar's test). Conclusion: Magnesium preparations combined with acid suppressants may diminish magnesium preparations' laxative effect; healthcare professionals should pay attention to this issue.
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Affiliation(s)
- M Maezawa
- Laboratory of Drug Informatics, Gifu Pharmaceutical Universit
| | - M Inoue
- Laboratory of Drug Informatics, Gifu Pharmaceutical University
| | - R Satake
- Laboratory of Drug Informatics, Gifu Pharmaceutical University
| | - W Wakabayashi
- Laboratory of Drug Informatics , Gifu Pharmaceutical University
| | - K Oura
- Laboratory of Drug Informatics, Gifu Pharmaceutical University
| | - F Goto
- Laboratory of Drug Informatics, Gics, Gifu Pharmaceutical University
| | - K Miyasaka
- Laboratory of Drug Informatics, Gics, Gifu Pharmaceutical University
| | - S Hirofuji
- Laboratory of Drug Informatics, Gifu Pharmaceutical University
| | - M Iwata
- Laboratory of Drug Informatics, Gifu Pharmaceutical University; Kifune Pharmacy
| | - T Suzuki
- Laboratory of Drug Informatics, Gifu Pharmaceutical University; Gifu Prefectural Government
| | - H Tanaka
- Laboratory of Drug Informatics, Gifu Pharmaceutical University; Chubu Yakuhin Co. Ltd
| | - S Nishida
- Department of Pharmacy, Gifu University Hospital
| | - S Shimizu
- Department of Pharmacy, Gifu University Hospital
| | - A Suzuki
- Department of Pharmacy, Gifu University Hospital
| | - K Iguchi
- Laboratory of Community Pharmacy, Gifu Pharmaceutical University, Gifu, Japan
| | - M Nakamura
- Laboratory of Drug Informatics, Gifu Pharmaceutical University; Corresponding author: Mitsuhiro Nakamura, Laboratory of Drug Informatics, Gifu Pharmaceutical University, 1-25-4 Daigaku-nishi, Gifu, 501-1196, Japan mnakamura@gifu-pu. ac. jp
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Sakaguchi Y, Mizukami M, Hiroka Y, Miyasaka K, Niwa K, Arizono K, Ichikawa N. Evaluation of neurotoxicity of anticancer drugs using nematode Caenorhabditis elegans as a model organism. J Toxicol Sci 2023; 48:311-321. [PMID: 37258236 DOI: 10.2131/jts.48.311] [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: 06/02/2023]
Abstract
It is well established that platinum-based drugs, including oxaliplatin (L-OHP) and cisplatin (CDDP), as well as microtubule inhibitors paclitaxel (PTX) and vincristine (VCR), are associated with chemotherapy-induced peripheral neuropathy (CIPN). In this study, we examined and compared the characteristics of neuropathies induced by L-OHP, CDDP, PTX, and VCR to evaluate whether Caenorhabditis elegans (C. elegans) could serve as a model organism for human CIPN. Worms were cultured on nematode growth medium plates, and L1 larvae synchronized by gel filtration were employed. We then performed bioassays and examined motility. In the motility test, exposure was performed for 2, 24, and 48 hr, and time-dependent effects were measured for each exposure time and 24 hr after terminating exposure. Herein, we observed that L-OHP and CDDP exerted concentration-dependent effects above a certain concentration, and PTX and VCR exerted concentration-dependent negative effects in the bioassay. Motility recovered in L-OHP-, PTX-, and VCR-treated worms on terminating exposure. However, CDDP exposure tended to reduce motility even 24 hr after terminating exposure. L-OHP exposure could decrease motility 2 hr after exposure, with a trend toward recovery 24 hr after terminating drug exposure. The findings of the present study revealed that C. elegans could exhibit neuropathy characteristics suggested to be similar to those observed in humans, indicating that this organism could be a suitable model to explore human CIPN.
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Affiliation(s)
- Yuko Sakaguchi
- College of Pharmaceutical Sciences, Ritsumeikan University
| | - Marin Mizukami
- College of Pharmaceutical Sciences, Ritsumeikan University
| | | | | | - Kyoko Niwa
- College of Pharmaceutical Sciences, Ritsumeikan University
| | - Koji Arizono
- Kumamoto University Graduate School of Pharmaceutical Sciences
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3
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Tanabe T, Miyasaka K, Saze T, Nishizawa K, Kobayashi T, Hayashi T, Nishi M. Surface Tritium Detection by Imaging Plate Technique. Fusion Science and Technology 2017. [DOI: 10.13182/fst02-a22645] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- T. Tanabe
- Center for Integrated Research in Science and Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603, Japan +81-52-789-5157
| | - K. Miyasaka
- Department of Nuclear Engineering, Graduate School of Engineering Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603, Japan, +81-52-789-5158
| | - T. Saze
- Radioisotope Center, Nagoya University Furo-cho, Chikusa-ku, Nagoya 464-8603, Japan, +81-52-789-2569
| | - K. Nishizawa
- Radioisotope Center, Nagoya University Furo-cho, Chikusa-ku, Nagoya 464-8603, Japan, +81-52-789-2569
| | - T. Kobayashi
- Tritium Engineering. Laboratory, Japan Atomic Energy Research Institute, Tokai-mura, Naka-gun, Ibaraki-ken 319-1195, Japan, +81-29-282-6390
| | - T. Hayashi
- Tritium Engineering. Laboratory, Japan Atomic Energy Research Institute, Tokai-mura, Naka-gun, Ibaraki-ken 319-1195, Japan, +81-29-282-6390
| | - M. Nishi
- Tritium Engineering. Laboratory, Japan Atomic Energy Research Institute, Tokai-mura, Naka-gun, Ibaraki-ken 319-1195, Japan, +81-29-282-6390
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Tanabe T, Miyasaka K, Sugiyama K, Masaki K, Kodama K, Miya N. Surface Distribution of Tritium on Graphite Tiles of Divertor Area in JT-60U. Fusion Science and Technology 2017. [DOI: 10.13182/fst02-a22710] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- T. Tanabe
- Center for Integrated Research in Science and Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603, Japan, +81-52-789-5157
| | - K. Miyasaka
- Department of Nuclear Engineering, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603, Japan +81-52-789-5158
| | - K. Sugiyama
- Department of Nuclear Engineering, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603, Japan +81-52-789-5158
| | - K. Masaki
- Department of Fusion Facilities, Japan Atomic Energy Research Institute, Naka-machi, Naka-gun, Ibaraki 311-0193, Japan +81-29-270-7430
| | - K. Kodama
- Department of Fusion Facilities, Japan Atomic Energy Research Institute, Naka-machi, Naka-gun, Ibaraki 311-0193, Japan +81-29-270-7430
| | - N. Miya
- Department of Fusion Facilities, Japan Atomic Energy Research Institute, Naka-machi, Naka-gun, Ibaraki 311-0193, Japan +81-29-270-7430
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Tanabe T, Miyasaka K, Rubel M, Philipps V. Tritium and Deuterium Retention in Graphite Limiters in TEXTOR. Fusion Science and Technology 2017. [DOI: 10.13182/fst02-a22720] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- T. Tanabe
- Center for Integrated Research in Science and Engineering, Nagoya University, Nagoya 464-8603, Japan
| | - K. Miyasaka
- Department of Nuclear Engineering, Graduate School of Engineering, Nagoya University, Nagoya 464-8603, Japan
| | - M. Rubel
- Alfen Laboratory, Royal Institute of Technology, SE-100 44, Stockholm, Sweden
| | - V. Philipps
- Institut fuer Plasmaphysik, Forschungszentrum Juelich GmbH, D-52425 Juelich, Germany
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Suyama T, Ueda T, Fukasawa S, Imamura Y, Nakamura K, Miyasaka K, Sazuka T, Egoshi KI, Nihei N, Hamano M, Ichikawa T, Maruoka M. Combination of Gemcitabine and Paclitaxel as Second-line Chemotherapy for Advanced Urothelial Carcinoma. Jpn J Clin Oncol 2009; 39:244-50. [DOI: 10.1093/jjco/hyp003] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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7
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Miyasaka K, Terasaki O. Curvature-optimization of silica mesoporous crystals. Acta Crystallogr A 2007. [DOI: 10.1107/s0108767307094792] [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] [Indexed: 11/11/2022] Open
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8
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Suzuki K, Nishioka T, Aoyama H, Tsuchiya K, Shirato H, Miyasaka K. 2421. Int J Radiat Oncol Biol Phys 2006. [DOI: 10.1016/j.ijrobp.2006.07.831] [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] [Indexed: 10/24/2022]
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9
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Kinoshita R, Shimizu S, Katoh N, Onimaru R, Shirato H, Miyasaka K. 2717. Int J Radiat Oncol Biol Phys 2006. [DOI: 10.1016/j.ijrobp.2006.07.1133] [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] [Indexed: 12/01/2022]
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10
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Miyasaka K, Hosoya H, Sekime A, Ohta M, Amono H, Matsushita S, Suzuki K, Higuchi S, Funakoshi A. Association of ghrelin receptor gene polymorphism with bulimia nervosa in a Japanese population. J Neural Transm (Vienna) 2005; 113:1279-85. [PMID: 16362631 DOI: 10.1007/s00702-005-0393-2] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2005] [Accepted: 10/09/2005] [Indexed: 10/25/2022]
Abstract
Eating disorders (EDs) have a highly heterogeneous etiology and multiple genetic factors might contribute to their pathogenesis. Ghrelin, a novel growth hormone-releasing peptide, enhances appetite and increases food intake, and human ghrelin plasma levels are inversely correlated with body mass index. In the present study, we examined the 171T/C polymorphism of the ghrelin receptor (growth hormone secretagogue receptor, GHSR) gene in patients diagnosed with EDs, because the subjects having ghrelin gene polymorphism (Leu72Met) was not detected in a Japanese population, previously. In addition, beta3 adrenergic receptor gene polymorphism (Try64Arg) and cholecystokinin (CCK)-A receptor (R) gene polymorphism (-81A/G, -128G/T), which are both associated with obesity, were investigated. The subjects consisted of 228 Japanese patients with EDs [96 anorexia nervosa (AN), 116 bulimia nervosa (BN) and 16 not otherwise specified (NOS)]. The age- and gender-matched control group consisted of 284 unrelated Japanese subjects. The frequency of the CC type of the GHSR gene was significantly higher in BN subjects than in control subjects (chi(2) = 4.47, p = 0.035, odds ratio = 2.05, Bonferroni correction: p = 0.070), while the frequency in AN subjects was not different from that in controls. The distribution of neither beta3 adrenergic receptor gene nor CCK-AR polymorphism differed between EDs and control subjects. Therefore, the CC type of GHSR gene polymorphism (171T/C) is a risk factor for BN, but not for AN.
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Affiliation(s)
- K Miyasaka
- Department of Clinical Physiology, Tokyo Metropolitan Institute of Gerontology, Tokyo, Japan.
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11
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Kitani K, Kanai S, Miyasaka K, Carrillo MC, Ivy GO. Dose-dependency of Life Span Prolongation of F344/DuCrj Rats Injected with (−)deprenyl. Biogerontology 2005; 6:297-302. [PMID: 16463106 DOI: 10.1007/s10522-005-4804-4] [Citation(s) in RCA: 11] [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] [Received: 03/29/2005] [Accepted: 08/20/2005] [Indexed: 12/01/2022]
Abstract
The effect of (-)deprenyl (D) on prolonging survival has previously been reported in different species of animals. In rats, three studies reported a positive effect, while one study reported a shortening of life spans. In the present study, we attempted to clarify past discrepancies in the results based on the speculation that there exists a certain effective dose range for this effect of the drug. F344/DuCrj rats of both sexes began to receive subcutaneous (s.c.) injections of D at the age of 18 months at a dose of 0.25 mg/kg/injection (inj.), 3 times a week. Control animals were given a vehicle (a saline solution). Average life spans of animals (days) were significantly increased in both male (895 +/- 109.7, n=30; 967.8 +/- 88.6, n=30, control vs. D treated, P<0.01, t-test) and female (924.7 +/- 132.2, n=38; 987.1 +/- 133.4, n=39, P<0.05) rats by 8.1% and 6.7%, respectively. We have previously reported that a dose of 0.5mg/kg/inj. (s.c.) significantly increased the life span of male F344 rats, while a dose of 1.0 mg/kg/inj. somewhat shortened the life span, although the difference was not statistically significant. The results of the present study coupled with our previous reports clearly indicate that a proper dose of D within a certain dose range can significantly increase the life span of animals of both sexes, but that a greater dose becomes less effective and may actually adversely affect the life span of rats. The presence of this effective dose range of D may explain discrepancies in the effect of D on life spans of animals previously reported.
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Affiliation(s)
- K Kitani
- National Institute for Longevity Sciences, 36-3, Gengo, Moriokacho, Obu-shi, Tokyo, Japan.
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12
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Shirato H, Imura M, Fujino M, Onimaru R, Yamazaki K, Nishimura M, Miyasaka K. Intensity Synchronized Radiotherapy (ISRT) with Conventional Fractionation Schedule Using Fiducial Markers and Real-Time Tumor-Tracking Radiotherapy (RTRT) System for Locally Advanced Lung Cancer. Int J Radiat Oncol Biol Phys 2005. [DOI: 10.1016/j.ijrobp.2005.07.380] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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13
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Oita M, Onimaru R, Suzuk K, Aoyama H, Fujino M, Kato N, Kinoshita R, Fujita K, Shirato H, Miyasaka K. 321 Estimation of dose distribution from the fluoroscopy in real-time tumor tracking radiotherapy (RTRT) for stereotactic body radiotherapy (SBRT). Radiother Oncol 2005. [DOI: 10.1016/s0167-8140(05)81297-6] [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] [Indexed: 11/30/2022]
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Miyasaka K, Funakoshi A, Jimi A, Sazaki N, Kitani K. Manifestations of experimental acute pancreatitis in young and old rats. Arch Gerontol Geriatr 2005; 14:167-74. [PMID: 15374401 DOI: 10.1016/0167-4943(92)90051-5] [Citation(s) in RCA: 4] [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] [Received: 08/26/1991] [Revised: 11/13/1991] [Accepted: 11/15/1991] [Indexed: 11/21/2022]
Abstract
Two kinds of experimental pancreatitis were induced in young (4-6 month) and old (25-27 month) female Wistar rats: acute edematous pancreatitis was induced by intraperitoneal administration of a high dose of cerulein (40 micro/kg x 2) and acute hemorrhagic pancreatitis was intraductal injection of 1% deoxycholic acid. After these treatments, the plasma amylase concentration and pancreatic wet weight were determined and the pancreas was examined histologically. In the groups with cerulein induced pancreatitis one of eight old rats died, whereas all five young rats survived. There was no specific finding macroscopically in the liver, kidney, lung or heart of old rats at autopsy after cerulein injection. The plasma amylase concentration and the pancreatic wet weight were significantly increased by administration of cerulein or deoxycholic acid in both young and old rats. There was no significant difference in the plasma amylase concentrations in young and old rats after the induction of acute pancreatitis. The increase in pancreatic wet weight was less in old rats than in young ones after deoxycholic acid treatment, but similar in the two groups after cerulein injection. The extents of histological changes were also similar in young and old rats. Thus, no evidence that aging increases susceptibility to pancreatitis was obtained.
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Affiliation(s)
- K Miyasaka
- Department of Clinical Physiology, Tokyo Metropolitan Institute of Gerontology, Tokyo-173, Japan
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Miyasaka K, Volgyesi G, Katayama M, Tanabe S. Continuous cardiac output determination by thermodeprivation. J Anesth 2005; 5:205-12. [PMID: 15278620 DOI: 10.1007/s0054010050205] [Citation(s) in RCA: 4] [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] [Received: 01/10/1991] [Accepted: 01/23/1991] [Indexed: 10/26/2022]
Abstract
A modified thermodilution catheter (KATS catheter) capable of monitoring continuous cardiac output by thermodeprivation and preserving its conventional function was devised. The KATS catheter has a thermistor incorporated closer to the tip of the catheter in addition to the usual thermistor used for conventional thermodilution. This additional thermistor is heated by a constant electric current but is capable of measuring its own temperature. The degree of heat deprivation is detected as the cooling of the thermistor, which is proportionally larger with larger blood velocity. Since blood flow is not the only source of heat deprivation, the actual formula was empirically derived by performing in vitro studies. Cardiac output can be determined by assuming the cross sectional area of the pulmonary artery is stationary. Calibration can be derived from a cardiac output measurement by the usual thermodilution method with the same catheter. The KATS catheter readings correlated significantly with conventional thermodilution values and electromagnetic flowmeter readings in anesthetized dogs. Continuous cardiac output measurement by the KATS catheter appears to be a promising technique.
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Affiliation(s)
- K Miyasaka
- Pathophysiology Research Laboratory, National Children's Medical Research Center, 3-35-31 Taishido, Setagaya, Tokyo, Japan
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Miyasaka K, Shimizu N, Kojima J. Recent trends in pediatric fluid therapy. Methods Find Exp Clin Pharmacol 2004; 26:287-94. [PMID: 15319807] [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: 04/30/2023]
Abstract
Virtually all hospitalized pediatric patients require some form of intravenous fluid administration. The foundation of current pediatric fluid therapy practice was formulated in the 1950s when pediatricians were dealing with relatively simple dehydration and normal homeostasis could largely be assumed. Recent advances in pediatric medicine have resulted in increased severity of illness and normal physiology can no longer be assumed. The traditional approach to pediatric fluid therapy has been recently challenged by the syndrome of inappropriate secretion of antidiuretic hormone (SIADH), cerebral salt wasting syndrome (CSWS), diabetic ketoacidosis (DKA) and hyponatremia caused by the inappropriate use of hypotonic solutions, all of which involve unusual sodium and serum osmolarity dynamics causing life threatening central nervous system (CNS) pathophysiology. In this review, we give an overview of the recent understanding of pediatric fluid therapy. The widespread use of acetate in place of lactate as a bicarbonate precursor and the expanding role of nonalbumin plasma expanders in pediatrics are also discussed as they will play a clinical role in the near future.
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Affiliation(s)
- K Miyasaka
- Department of Anesthesia and ICU, National Center for Child Health and Development, Setagaya, Tokyo, Japan.
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Shimazoe T, Nakamura S, Kobayashi K, Watanabe S, Miyasaka K, Kono A, Funakoshi A. Role of 5-ht1b receptors in entrainment disorder of otsuka long evans tokushima fatty (oletf) rats. Neuroscience 2004; 123:201-5. [PMID: 14667454 DOI: 10.1016/j.neuroscience.2003.08.024] [Citation(s) in RCA: 10] [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] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The role of 5-HT1A and 5-HT1B receptors in entrainment function was studied in Otsuka Long Evans Tokushima fatty (OLETF) rats and control Long Evans Tokushima Otsuka (LETO) rats. Light-induced (100 lux, 30 min) Fos expression in the suprachiasmatic nucleus was studied. Light-induced Fos expression was significantly decreased in OLETF rats compared to that in LETO rats. The decrease of light-induced Fos expression in OLETF rats was significantly reversed by pretreatment with the 5-HT1B receptor antagonist, isamoltan (3 mg/kg, i.p.). Simultaneous administration of CGS12066B (5 mg/kg, i.p.), a 5-HT1B agonist, blocked the reversal effect of isamoltan on Fos expression. Fos expression was not changed in LETO rats by pretreatment with isamoltan (3 mg/kg, i.p.). The Fos expression in LETO and OLETF rats was significantly decreased by pretreatment with the 5-HT1A antagonist, WAY-100,635. Phase shifts in locomotor activity paralleled the Fos expression. Light-induced phase shifts of locomotor activity in OLETF rats were significantly smaller than those in LETO rats. The phase shifts were significantly increased by isamoltan (3 mg/kg, i.p.) in OLETF rats. These results suggest that 5-HT1B receptors are involved in the reduced entrainment function of OLETF rats.
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Affiliation(s)
- T Shimazoe
- Department of Pharmacology, Graduate School of Pharmaceutical Sciences, Kyushu University, 812-8582, Fukuoka, Japan.
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Fujino M, Harada T, Onimaru R, Shimizu S, Yamazaki K, Shirato H, Dosaka-Akita H, Nishimura M, Miyasaka K. Feasibility study of real-time tumor-tracking radiotherapy system for lung tumors. Int J Radiat Oncol Biol Phys 2003. [DOI: 10.1016/s0360-3016(03)01358-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Aoyama H, Shirato H, Chang T, Ushikoshi S, Asano T, Kudo K, Miyasaka K. The use of MR angiography and CT angiography in stereotactic radiosurgery of intracranial AVMs. Int J Radiat Oncol Biol Phys 2003. [DOI: 10.1016/s0360-3016(03)01285-9] [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] [Indexed: 11/24/2022]
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20
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Oka M, Terae S, Kobayashi R, Sawamura Y, Kudoh K, Tha KK, Yoshida M, Kaneda M, Suzuki Y, Miyasaka K. MRI in methotrexate-related leukoencephalopathy: Disseminated necrotising leukoencephalopathy in comparison with mild leukoencephalopathy. Neuroradiology 2003; 45:493-7. [PMID: 12761601 DOI: 10.1007/s00234-003-0983-3] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2003] [Accepted: 02/24/2003] [Indexed: 10/26/2022]
Abstract
We report two fatal cases of methotrexate (MTX)-induced disseminated necrotising leukoencephalopathy (DNL) in which MRI was repeated from the onset. Initial T2-weighted images showed multiple areas of high signal, mainly in deep cerebral white matter, which on follow-up, spread and coalesced to involve the entire white matter. Small irregular low-signal foci on T2-weighted images were seen within the high-signal lesions. Multiple areas of contrast enhancement corresponded to these low-signal foci. The condition of both patients deteriorated and they died. We compared their MRI findings with those of seven patients with mild MTX-related leukoencephalopathy, six of whom were asymptomatic; one had transient neurological symptoms. They showed no contrast enhancement, but rather mild-to-moderate diffuse high signal in deep white matter, which later disappeared. These findings suggest that multiple low-signal foci on T2-weighted images with contrast enhancement may be characteristic of DNL, and that contrast-enhanced imaging is useful to differentiate this condition from mild leukoencephalopathy.
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Affiliation(s)
- M Oka
- Department of Radiology, Hokkaido Graduate University School of Medicine, 060-8638, Sapporo, Japan.
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Miyamoto N, Kodama Y, Endo H, Shimizu T, Miyasaka K. Hepatic artery embolization for postoperative hemorrhage in upper abdominal surgery. Abdom Imaging 2003; 28:347-53. [PMID: 12719904 DOI: 10.1007/s00261-002-0041-3] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
BACKGROUND The purpose of this study was to evaluate angiographic findings and radiologic and clinical results of transcatheter arterial embolization (TAE) of the hepatic artery for hemorrhage after upper abdominal surgery. METHODS Ten patients (nine male, one female, mean age = 63.5 years) with postoperative hemorrhage underwent emergency hepatic artery embolization. We retrospectively analyzed the angiographic findings and the effectiveness of TAE. RESULTS Angiography demonstrated pseudoaneurysms (n = 6) and extravasation (n = 5). Portal veins were not compromised in any patient. The bleeding points were at the gastroduodenal artery (n = 3), proper hepatic artery (n = 3), right hepatic artery (n = 2), left hepatic artery (n = 1), and intrahepatic artery (n = 2). Embolization was performed at the extrahepatic site (n = 6) and intrahepatic site (n = 4). TAE was successful in eight patients. Hemostasis was achieved in eight patients. Two patients in whom TAE was not successful died of bleeding after TAE. In six patients whose collateral arteries were visualized at TAE, hypoxic hepatic failure was avoided and the patients had a favorable clinical course. CONCLUSION TAE is a useful treatment for postoperative hemorrhage, but the presence of collateral arteries at the time of TAE can affect the patients' prognoses.
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Affiliation(s)
- N Miyamoto
- Department of Radiology, Hokkaido University School of Medicine, N15, W7, Kita-ku, Sapporo 060-8638, Japan
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Miyasaka K, Kondo Y, Asahara S, Tamura T, Suzuki Y. Effect of intravenous infusion of NIK-716 in anesthetized pediatric patients. Methods Find Exp Clin Pharmacol 2002; 24:697-701. [PMID: 12616964 DOI: 10.1358/mf.2002.24.10.802321] [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] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
NIK-716 is a maintenance fluid based on the new concept of containing acetate as a base source and 5% glucose as an energy source. It was administered to pediatric patients under general anesthesia for less invasive surgical operations, and its efficacy was investigated by performing blood chemistry examination and urinalysis before and after administration. For efficacy assessment, the three items selected as efficacy parameters, i) the replacement and maintenance of water (assessment of hydration and urine output); ii) the maintenance of serum electrolytes (Na and K); and iii) the utilization of glucose (blood glucose and urinary glucose), were evaluated based on the results of laboratory examination (hematology, blood chemistry and urinalysis), and overall improvement was rated on the basis of total scores of these assessment items. No adverse events or abnormal laboratory values attributable to the maintenance fluid were observed in any of the 25 children administered NIK-716. In an overall improvement rating, NIK-716 proved markedly effective or effective in 79.2% of the 24 children evaluated. The overall safety rating was judged as 'no problem' in all 25 children. These findings suggest that NIK-716 is a useful and safe maintenance fluid that can be administered to pediatric patients during the course of surgery.
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Affiliation(s)
- K Miyasaka
- Department of Anesthesia and ICU, National Center for Child Health and Development, Tokyo, Japan.
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Tha KK, Terae S, Sugiura M, Nishioka T, Oka M, Kudoh K, Kaneko K, Miyasaka K. Diffusion-weighted magnetic resonance imaging in early stage of 5-fluorouracil-induced leukoencephalopathy. Acta Neurol Scand 2002; 106:379-86. [PMID: 12460146 DOI: 10.1034/j.1600-0404.2002.01253.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.5] [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: 01/10/2023]
Abstract
We report a case of 5-fluorouracil (5-FU)-induced leukoencephalopathy in which magnetic resonance imaging (MRI) of the brain, including diffusion-weighted imaging (DWI), was performed serially. The initial T2-weighted and FLAIR images showed diffuse mild hyperintensity in bilateral deep cerebral white matter and corpus callosum, which on T1WI appeared as non-enhanced faint hypointensity. Isotropic DWI disclosed the abnormality as well-conspicuous diffuse hyperintensity with decreased ADC. Serial studies revealed that majority of the abnormal signal intensity on these sequences resolved, and the decreased ADC values approached normal. Some hyperintensity remained in the deep cerebral white matter and the splenium, but no further significant ADC change after normalization was noted. Measurement of ADC along the three orthogonal directions showed the presence of directional dependence of diffusion throughout the length of study. These findings suggest that early stage of 5-FU-induced leukoencephalopathy is associated with reversible restricted diffusion and preservation of anisotropy. Diffusion-weighted imaging may be useful for the diagnosis.
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Affiliation(s)
- K K Tha
- Department of Radiology, Hokkaido University School of Medicine, Kita-ku, Sapporo, Japan.
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Aoyama H, Kamada K, Shirato H, Takeuchi F, Komae T, Kuriki S, Iwasaki Y, Miyasaka K. Integration of functional brain information into treatment planning of stereotactic irradiation using magnetoencephalography and MR-axonography. Int J Radiat Oncol Biol Phys 2002. [DOI: 10.1016/s0360-3016(02)03481-8] [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] [Indexed: 11/30/2022]
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Kitamura K, Shirato H, Onimaru R, Shimizu T, Kodama Y, Endo H, Shimizu S, Miyasaka K. Feasibility study of hypofractionated gated irradiation using a real-time tumor-tracking radiation therapy system for malignant liver tumors. Int J Radiat Oncol Biol Phys 2002. [DOI: 10.1016/s0360-3016(02)03273-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Sudo K, Miyazaki Y, Tajima Y, Matsumoto A, Tashiro K, Miyasaka K. Spontaneous resolution of idiopathic syringomyelia. Neurology 2002; 58:1576-7; author reply 1577. [PMID: 12034809 DOI: 10.1212/wnl.58.10.1576-a] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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Tang SS, Shimizu T, Kishimoto R, Kodama Y, Miyasaka K. Analysis of portal venous waveform after living-related liver transplantation with pulsed Doppler ultrasound. Clin Transplant 2001; 15:380-7. [PMID: 11737113 DOI: 10.1034/j.1399-0012.2001.150603.x] [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] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
We evaluate the portal venous waveform (PVW) with pulsed Doppler ultrasound (US) after living-related liver transplantation (LRLT) and correlate it with subsequent abnormalities. In the first 2 wk after LRLT, pulsed Doppler US demonstrated three types of PV waveform (PVW) in 33 recipients: non-phasic PVW in 19 patients, pulsatile in 10, and turbulent in 4. In the pulsatile PVW group, arterio-portal (A-P) shunt was confirmed in three grafts by either arteriograhy or computed tomography during hepatic arteriography. A severe stenosis in the grafted vein was confirmed in one case by both US and venography. The pulsatile PVW in the remaining six cases spontaneously disappeared and turned to the non-phasic PVW without treatment. The graft volume/liver standard volume (GV/SV) ratio was significantly smaller in the pulsatile PV waveform group than in the non-phasic PVW group (p<0.01). In the turbulent PVW group, aneurysmal-like dilatation of the portal vein at the umbilical portion was formed in 3 of the 4 patients. The pulsatile waveform in the PV is frequently observed with pulsed Doppler after LRLT, especially in patients that received small grafts. We should keep in mind that they often disappear without any treatment, although some examples of pulsatile waveforms represent vascular complications.
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Affiliation(s)
- S S Tang
- Department of Radiology, Hokkaido University School of Medicine, North-15, West-7, Kita-Ku, Sapporo 060-8638, Japan.
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Ushikoshi S, Houkin K, Kuroda S, Miyasaka K, Iwasaki Y. [Intentional neck-plastic incomplete clipping followed by coil embolization for broad-necked distal BA aneurysms]. No Shinkei Geka 2001; 29:1215-20. [PMID: 11797356] [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
OBJECTIVE We report three patients with broad-necked distal basilar artery (BA) aneurysms treated with intentional incomplete clipping followed by endovascular occlusion using Guglielmi detachable coils. METHODS The location of the aneurysms was BA bifurcation in one patient and BA-superior cerebellar artery (SCA) in two. One patient presented with acute subarachnoid hemorrhage and two patients had incidental aneurysms. In two patients, endovascular treatment was thought to be difficult considering the morphology of the aneurysms and surgical treatment was performed as the first choice of treatment. One patient with a BA-SCA aneurysm underwent endovascular treatment using a remodelling technique first. However, it was impossible to place the coil preserving SCA, so surgical treatment was performed. In all patients, the attempt to pursue complete clipping was considered to be accompanied with high risks of morbidity, so neck-plastic incomplete clipping was performed intentionally. One to six days after the surgery, coil embolization was performed. RESULTS In all patients, complete occlusion of the aneurysms was achieved and all patients had excellent clinical outcomes. CONCLUSION Intentional neck-plastic incomplete clipping followed by endovascular coiling may be a useful treatment option for patients with broad-necked distal BA aneurysms.
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Affiliation(s)
- S Ushikoshi
- Department of Radiology, Hokkaido University School of Medicine, Kita 15, Nishi 7, Kita-ku, Sapporo, Hokkaido 060-8638, Japan
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Nishioka T, Shirato H, Tsuchiya K, Tsukamoto E, Ohomori K, Yamazaki A, Aoyama H, Nishioka S, Miyasaka K. 18FDG-PET/MRI/CT fusion-guided conformal radiotherapy for nasopharyngeal and oropharyngeal carcinomas: a differential dose delivery based on functional imaging. Int J Radiat Oncol Biol Phys 2001. [DOI: 10.1016/s0360-3016(01)01899-5] [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] [Indexed: 11/29/2022]
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Onimaru R, Shirato H, Shimizu S, Kitamura K, Miyasaka K, Fukumoto S, Akita H. Tumor control and respiratiory function after stereotactic irradiation (STI) for primary and metastatic lung cancer. Int J Radiat Oncol Biol Phys 2001. [DOI: 10.1016/s0360-3016(01)02460-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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31
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Miyasaka K, Masuda M, Kanai S, Ohta M, Suzuki S, Tateishi K, Funakoshi A. Inhibitory effect of somatostatin on cholecystokinin release is independent of luminal cholecystokinin-releasing factor content in conscious rats. Pancreas 2001; 23:414-20. [PMID: 11668212 DOI: 10.1097/00006676-200111000-00013] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/10/2022]
Abstract
INTRODUCTION Exclusion of bile-pancreatic juice from the intestine increases pancreatic secretion via cholecystokinin (CCK) release in conscious rats. Luminal CCK-releasing factor (LCRF), purified from rat intestinal secretions, is an intraluminal regulator of CCK secretion during bile-pancreatic juice diversion. AIMS Because somatostatin is a potent inhibitor of CCK release and pancreatic secretion, the inhibitory effect of somatostatin on LCRF was examined. METHODOLOGY Rats were prepared with bile and pancreatic cannulae and two duodenal cannulae and with an external jugular vein cannula. The experiments were conducted without anesthesia. After 1.5-hour basal collection of pancreatic juice with bile-pancreatic juice return, bile-pancreatic juice was diverted for 2 hours, during which time somatostatin (2, 10 nmol/kg/h) was infused intravenously. The rats were killed before and 1 and 2 hours after bile-pancreatic juice diversion. To examine the effect of luminal somatostatin, 50 or 200 nmol/kg/h of somatostatin was infused into the duodenum. The plasma CCK and luminal content of LCRF were measured by specific radioimmunoassays. RESULTS Bile-pancreatic juice diversion significantly increased pancreatic secretion, plasma CCK, and LCRF levels. Intravenous infusion of somatostatin inhibited CCK release and pancreatic secretion, but not LCRF content. Luminal administration of somatostatin did not show any effect. CONCLUSION Inhibitory effect of circulating somatostatin on CCK release and pancreatic secretion is independent of LCRF content.
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Affiliation(s)
- K Miyasaka
- Department of Clinical Physiology, Tokyo Metropolitan Institute of Gerontology, 35-2 Sakaecho, Itabashiku, Tokyo-173-0015, Japan.
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Abstract
OBJECTIVES The purpose of this study was to examine the effect of 2-methacryloyloxyethyl phenyl phosphoric acid (Phenyl-P)/2-hydroxyethyl methacrylate (HEMA) acetone-based primer on moist dentin surfaces that were preconditioned with ethylenediaminetetraacetate (EDTA) to remove the smear layer. METHODS Bovine dentin were prepared with 180-grit paper, conditioned with 0.5M EDTA (pH 7.4) for 60s followed by water rinsing and then blot drying. Each surface was then primed with Phenyl-P/30 wt% HEMA in acetone for 10s followed by blot drying. A light-cured bonding agent was then applied, cured and trimmed to give dumbbell-shaped specimens. The Phenyl-P concentration ranged from 1 to 20 wt%. During the bonding procedure, no compressed air was used. After storage in water at 37 degrees C for one day, tensile bond strengths were measured and analyzed using one-way ANOVA. Dentin discs treated under the same conditions were observed under a scanning electron microscope (SEM). RESULTS When the concentration of Phenyl-P was 12 wt%, the highest mean tensile bond strength was obtained (27 MPa). It was significantly higher than that of the 3, 5, 15 or 20 wt% groups (9-11 MPa) (p<0.05). The samples of 1 wt% group were all broken during trimming the dumbbell-shaped specimens. SEM observations showed a 1 microm-thick layer of hybridized dentin after polished cross-sections were chemically challenged with 6N HCl for 30s and then 1% NaOCl for 60 min. SIGNIFICANCE The experimental Phenyl-P/HEMA acetone primer is effective in bonding resin to EDTA-conditioned dentin. Acetone as a solvent for Phenyl-P/HEMA primer has the clinical advantage of not requiring an air-stream to evaporate the solvent. The experimental bonding procedure can minimize the skin irritation by HEMA.
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Affiliation(s)
- K Miyasaka
- Institute of Biomaterials and Bioengineering, Tokyo Medical and Dental University, Tokyo, Japan.
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Aoyama H, Shirato H, Onimaru R, Miyasaka K. Hypofractionated Stereotactic Radiotherapy (HSRT) alone without whole brain irradiation for solitary and oligo brain metastatic patients using non-invasive fixation of skull. Int J Radiat Oncol Biol Phys 2001. [DOI: 10.1016/s0360-3016(01)02068-5] [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] [Indexed: 10/18/2022]
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Yonesaka A, Onimaru R, Shirato H, Kitamura K, Aoyama H, Seki T, Hida K, Iwasaki Y, Miyasaka K. Application of real-time tracking radiation therapy (RTRT) system for the treatment of spinal and paraspinal diseases. Int J Radiat Oncol Biol Phys 2001. [DOI: 10.1016/s0360-3016(01)01873-9] [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] [Indexed: 11/15/2022]
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Sakamoto T, Shirato H, Aoyama H, Onimaru R, Sawamura Y, Suzuki K, Miyasaka K. Outcome analysis of patient-perceived disability in patients with vestibular schwannoma treated by fractionated stereotactic radiotherapy (SRT). Int J Radiat Oncol Biol Phys 2001. [DOI: 10.1016/s0360-3016(01)01932-0] [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] [Indexed: 10/18/2022]
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Harada J, Dohi M, Mogami T, Fukuda K, Miki K, Furuta N, Kishimoto K, Simizu T, Miyasaka K. Initial experience of percutaneous renal cryosurgery under the guidance of a horizontal open MRI system. Radiat Med 2001; 19:291-6. [PMID: 11837579] [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
OBJECTIVE The aim of this study was to obtain preliminary results of cryoablation of renal tumors by using a percutaneous approach guided by a horizontal open MRI system, and to assess the safety and efficacy of this procedure. MATERIALS AND METHODS Four patients with renal tumors underwent percutaneous cryosurgery with local anesthesia using a horizontal open MRI system (AIRIS II, Hitachi Medical Corp., Tokyo, Japan). The size of the mass was radiographically documented as 4 cm or less in diameter. A 2- or 3-mm cryoprobe was advanced into the renal mass under real-time MR monitoring. Growth of the iceball during cryoablation was monitored by two-dimensional MR images. Follow-up dynamic CT and physical examination were done after two weeks and six weeks. RESULT MR imaging demonstrated the iceballs as sharply marginated regions of signal loss that expanded and engulfed the renal mass with clear contrast between the iceball and surrounding tissue. Cryoablated tumors resolved, and there were no serious complications and no clinically significant changes during the procedures and follow-up study. CONCLUSION In this limited clinical trial of percutaneous renal tumor surgery, cryoablation demonstrated its feasibility with minimal morbidity. Intraprocedual MR-guided cryosurgery can be used as a safe modality, although further studies are necessary to determine the long-term efficacy of this procedure.
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Affiliation(s)
- J Harada
- Department of Radiology, Jikei University School of Medicine, Kashiwa Hospital, Chiba, Japan
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Suzuki S, Takiguchi S, Sato N, Kanai S, Kawanami T, Yoshida Y, Miyasaka K, Takata Y, Funakoshi A, Noda T. Importance of CCK-A receptor for gallbladder contraction and pancreatic secretion: a study in CCK-A receptor knockout mice. Jpn J Physiol 2001; 51:585-90. [PMID: 11734079 DOI: 10.2170/jjphysiol.51.585] [Citation(s) in RCA: 38] [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] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Bile and pancreatic secretions were determined in a CCK-A receptor deficient mouse mutant generated by gene targeting in embryonic stem cells. The targeting vector contained lacZ and neo insertions in exon 2. Under the urethane anesthesia, the common bile duct was cannulated, and the mixture of bile-pancreatic juice was collected every 30 min. After the 1 h basal secretion, CCK-8 (0.5 and 1.0 nmol/kg), acetylcholine (500 nmol/kg), and neuromedin C (1.0 micromol/kg) were injected subcutaneously, and the secretions were collected following 1 h. Amylase and bile acid outputs were determined as parameters of pancreatic secretion and gallbladder contraction, respectively. In some CCK-A receptor (+/-) animals, LacZ staining was performed. CCK-8 significantly increased amylase and bile acid outputs in CCK-A receptor (+/+) and (+/-) mice, whereas no response was observed in (-/-) mice. Neuromedin C and acetylcholine increased amylase secretion in CCK-A receptor (-/-) mice similar to (+/-) and (+/+) mice. The same doses of neuromedin C and acetylcholine could not increase bile acid secretion. The gallbladder smooth muscles, pancreatic acinar cells, duct cells, and islets were stained by LacZ. CCK and CCK-A receptor are important for pancreatic secretion and gallbladder contraction. Neuromedin C and acetylcholine may compensate pancreatic function, but not gallbladder contraction.
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Affiliation(s)
- S Suzuki
- Department of Clinical Physiology, Tokyo Metropolitan Institute of Gerontology, Itabashi-ku, Tokyo, 173-0015 Japan
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Imai Y, Nakagawa S, Ito Y, Kawano T, Slutsky AS, Miyasaka K. Comparison of lung protection strategies using conventional and high-frequency oscillatory ventilation. J Appl Physiol (1985) 2001; 91:1836-44. [PMID: 11568170 DOI: 10.1152/jappl.2001.91.4.1836] [Citation(s) in RCA: 112] [Impact Index Per Article: 4.9] [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: 11/22/2022] Open
Abstract
This study compared pathophysiological and biochemical indexes of acute lung injury in a saline-lavaged rabbit model with different ventilatory strategies: a control group consisting of moderate tidal volume (V(T)) (10-12 ml/kg) and low positive end-expiratory pressure (PEEP) (4-5 cmH(2)O); and three protective groups: 1) low V(T) (5-6 ml/kg) high PEEP, 2-3 cmH(2)O greater than the lower inflection point; 2) low V(T) (5-6 ml/kg), high PEEP (8-10 cmH(2)O); and 3) high-frequency oscillatory ventilation (HFOV). The strategy using PEEP > inflection point resulted in hypotension and barotrauma. HFOV attenuated the decrease in pulmonary compliance, the lung inflammation assessed by polymorphonuclear leukocyte infiltration and tumor necrosis factor-alpha concentration in the alveolar space, and pathological changes of the small airways and alveoli. Conventional mechanical ventilation using lung protection strategies (low V(T) high PEEP) only attenuated the decrease in oxygenation and pulmonary compliance. Therefore, HFOV may be a preferable option as a lung protection strategy.
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Affiliation(s)
- Y Imai
- Pathophysiology Research Laboratory, National Children's Medical Research Center, 3-35-31 Taishido, Setagaya-ku, Tokyo 154-8509, Japan
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Shimizu S, Shirato H, Ogura S, Akita-Dosaka H, Kitamura K, Nishioka T, Kagei K, Nishimura M, Miyasaka K. Detection of lung tumor movement in real-time tumor-tracking radiotherapy. Int J Radiat Oncol Biol Phys 2001; 51:304-10. [PMID: 11567803 DOI: 10.1016/s0360-3016(01)01641-8] [Citation(s) in RCA: 224] [Impact Index Per Article: 9.7] [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: 11/23/2022]
Abstract
PURPOSE External radiotherapy for lung tumors requires reducing the uncertainty due to setup error and organ motion. We investigated the three-dimensional movement of lung tumors through an inserted internal marker using a real-time tumor-tracking system and evaluated the efficacy of this system at reducing the internal margin. METHODS AND MATERIALS Four patients with lung cancer were analyzed. A 2.0-mm gold marker was inserted into the tumor. The real-time tumor-tracking system calculates and stores three-dimensional coordinates of the marker 30 times/s. The system can trigger the linear accelerator to irradiate the tumor only when the marker is located within the predetermined "permitted dislocation." The value was set at +/-1 to +/-3 mm according to the patient's characteristics. We analyzed 10,413-14,893 data sets for each of the 4 patients. The range of marker movement during normal breathing (beam-off period) was compared with that during gated irradiation (beam-on period) by Student's t test. RESULTS The range of marker movement during the beam-off period was 5.5-10.0 mm in the lateral direction (x), 6.8-15.9 mm in the craniocaudal direction (y) and 8.1-14.6 mm in the ventrodorsal direction (z). The range during the beam-on period was reduced to within 5.3 mm in all directions in all 4 patients. A significant difference was found between the mean of the range during the beam-off period and the mean of the range during the beam-on period in the x (p = 0.007), y (p = 0.025), and z (p = 0.002) coordinates, respectively. CONCLUSION The real-time tumor-tracking radiotherapy system was useful to analyze the movement of an internal marker. Treatment with megavoltage X-rays was properly given when the tumor marker moved into the "permitted dislocation" zone from the planned position.
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Affiliation(s)
- S Shimizu
- Department of Radiation Medicine, Hokkaido University School of Medicine, Sapporo, Japan
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Oka M, Terae S, Kobayashi R, Kudoh K, Chu BC, Kaneko K, Yoshida M, Kaneda M, Suzuki Y, Miyasaka K. Diffusion-weighted MR findings in a reversible case of acute Wernicke encephalopathy. Acta Neurol Scand 2001; 104:178-81. [PMID: 11551240 DOI: 10.1034/j.1600-0404.2001.00098.x] [Citation(s) in RCA: 24] [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] [Indexed: 11/23/2022]
Abstract
We report a case of acute Wernicke encephalopathy (WE) in which apparent diffusion coefficient maps showed areas of increased diffusion in the bilateral medial thalami that corresponded to the hyperintense lesions on T2-weighted imaging. The hyperintense lesions on T2-weighted imaging disappeared with full recovery from symptoms. These findings suggest that the hyperintense lesions of the acute changes of WE include reversible vasogenic edema and are not caused by acute ischemia.
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Affiliation(s)
- M Oka
- Department of Radiology, Hokkaido University School of Medicine, N-15, W-7, Kita-ku, Sapporo, 060-8638, Japan.
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Hashimoto S, Shirato H, Kaneko K, Ooshio W, Nishioka T, Miyasaka K. Clinical efficacy of telemedicine in emergency radiotherapy for malignant spinal cord compression. J Digit Imaging 2001; 14:124-30. [PMID: 11720334 PMCID: PMC3607475 DOI: 10.1007/s10278-001-0011-2] [Citation(s) in RCA: 8] [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: 10/27/2022] Open
Abstract
The authors developed a Telecommunication-HElped Radiotherapy Planning and Information SysTem (THERAPIST), then estimated its clinical benefit in radiotherapy in district hospitals where consultation with the university hospital was required. The system consists of a personal computer with an image scanner and a digital camera, set up in district hospitals and directly connected via ISDN to an image server, and a treatment planning device set up in a university hospital. Image data and consultative reports are sent to the server. Radiation oncologists at the university hospital determine a treatment schedule and verify actual treatment fields. From 1998 to 1999, 12 patients with malignant spinal cord compression (MSCC) were treated by emergency radiotherapy with the help of this system. Image quality, transmission time, and cost benefit also were satisfactory for clinical use. The mean time between the onset of symptoms and the start of radiotherapy was reduced significantly from 7.1 days to 0.8 days (P < .05) by the introduction of the system. Five of 6 nonambulant patients became ambulant after the introduction of THERAPIST compared with 2 of 8 before the introduction of THERAPIST. The treatment outcome was significantly better after the introduction of the system (P < .05), and suggested to be beyond the international standard. The telecommunication-helped radiotherapy and information system was useful in emergency radiotherapy in district hospitals for patients with MSCC for whom consultation with experienced radiation oncologists at a university hospital was required.
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Affiliation(s)
- S Hashimoto
- Department of Radiation Medicine, Hokkaido University Graduate School of Medicine, Sapporo, Japan
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42
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Omatsu T, Okada F, Furuuchi K, Okubo Y, Takahashi Y, Tada M, Miyazaki YJ, Taniguchi Y, Shirato H, Miyasaka K, Moriuchi T. Overexpression of homeobox gene HOXD3 induces coordinate expression of metastasis-related genes in human lung cancer cells. Int J Cancer 2001; 93:516-25. [PMID: 11477555 DOI: 10.1002/ijc.1357] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Homeobox-containing genes are expressed in spatiotemporal fashion during embryogenesis and act as master transcription-regulating factors which control the expression of a variety of genes involved in morphogenesis. They are also expressed in a tissue-specific manner in normal adult tissues and appear to give cells spatial information in the maintenance of their architectural integrity. We transfected a HOXD3 class I homeobox-containing gene into human lung cancer A549 cells and investigated alterations in gene expressions and phenotypes related to the maintenance of tissue architecture in HOXD3-overexpressing A549 cells. In the HOXD3-overexpressing cell lines, expression of E-cadherin was lost and plakoglobin was strongly repressed, whereas integrin alpha3 and beta3 were up-regulated and N-cadherin and integrin alpha4 were newly expressed. Compared with parental and control transfectant lines, the HOXD3-overexpressing cell lines showed highly motile and invasive activity. Blocking experiments using anti-integrin beta1 and beta3 suggested that the increased haptotaxis of the HOXD3-overexpressing cells to vitronectin resulted from increased expression and activation of integrin alphavbeta3, and that overexpression of the HOXD3 gene converted the integrin beta1-dependent haptotaxis to fibronectin into both integrin beta1- and beta3-dependent one. HOXD3 overexpression increased production of matrix-degrative enzymes including matrix metalloproteinase-2 and urokinase-plasminogen activator. When the tumor cells were intravenously injected into the tail veins of nude mice, HOXD3 transfectants formed a significantly large number of metastatic foci in lungs compared with the control transfectants. These findings suggest that HOXD3 can act as a metastasis-promoting gene in human lung cancer A549 cells.
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43
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Tateishi U, Terae S, Ogata A, Sawamura Y, Suzuki Y, Abe S, Miyasaka K. MR imaging of the brain in lymphomatoid granulomatosis. AJNR Am J Neuroradiol 2001; 22:1283-90. [PMID: 11498415 PMCID: PMC7975211] [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: 02/21/2023]
Abstract
BACKGROUND AND PURPOSE Clinical diagnosis of lymphomatoid granulomatosis (LG) of the brain, in patients without skin or chest lesions, usually is difficult because of the nonspecific neurologic manifestations, laboratory data, and CT appearance. Our aim was to characterize the MR appearance of LG of the brain. METHODS We retrospectively reviewed the MR images in four patients (35 to 72 years old) with histologically confirmed LG of the brain. RESULTS On T2-weighted images, we noted diffuse hyperintense lesions in the cerebral white matter bilaterally (n = 3), in the brain stem and cerebellar hemisphere (n = 1), and patchy hyperintense lesions the brain stem (n = 2). On contrast-enhanced T1-weighted images, we observed multiple punctate or linear enhancements residing along the perivascular space (n = 4), nodular enhancements (n = 2), ringlike enhancements (n = 1), and a large, enhanced mass (n = 1). All patients had multifocal lesions. CONCLUSION Although the MR appearance of LG of the brain varies, multiple punctate or linear enhancements that reside along the perivascular space suggest LG.
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Affiliation(s)
- U Tateishi
- Department of Radiology, Hokkaido University School of Medicine, N-15 W-7, Kita-ku, Sapporo, Hokkaido 060-8638, Japan
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44
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Furukawa M, Terae S, Chu BC, Kaneko K, Kamada H, Miyasaka K. MRI in seven cases of tacrolimus (FK-506) encephalopathy: utility of FLAIR and diffusion-weighted imaging. Neuroradiology 2001; 43:615-21. [PMID: 11548166 DOI: 10.1007/s002340100545] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.0] [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: 12/17/2022]
Abstract
We assessed the utility of fluid-attenuated inversion-recovery (FLAIR) and diffusion-weighted (DWI) images in investigation of tacrolimus (FK-506) encephalopathy, and to see whether we could predict its cause from clinical and imaging data. In seven patients with presumed FK-506 toxicity the areas involved on MRI were similar to those in cyclosporin A (CsA) toxicity. The abnormal signal was most evident on FLAIR in all cases. In three of four patients who underwent DWI, no diffusion abnormalities were detected; in the remaining patient, increased diffusion was seen in the deep white matter bilaterally on the apparent diffusion coefficient map, consistent with the findings on T2-weighted spin-echo and FLAIR images. Five of the six patients for whom we had clinical data showed sudden changes in electrolyte or fluid equilibrium due to diarrhoea, a polyuria or oliguria one day before or on the day of onset of the central nervous system disturbances. We speculate that FK-506 encephalopathy is triggered by the disturbance of the electrolyte and/or fluid equilibrium, given a certain serum level of FK-506.
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Affiliation(s)
- M Furukawa
- Department of Radiology, Yamaguchi University School of Medicine, Ube, Japan
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45
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Abstract
We describe the thin-section CT appearances of HTLV-1-associated bronchopneumonopathy, with histopathological correlation, in two biopsy proven cases.
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Affiliation(s)
- U Tateishi
- Department of Radiology, Hokkaido University School of Medicine, Sapporo, Japan.
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46
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Kurosawa M, Iijima S, Funakoshi A, Kawanami T, Miyasaka K, Bucinskaite V, Lundeberg T. Cholecystokinin-8 (CCK-8) has no effect on heart rate in rats lacking CCK-A receptors. Peptides 2001; 22:1279-84. [PMID: 11457521 DOI: 10.1016/s0196-9781(01)00452-1] [Citation(s) in RCA: 12] [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: 01/28/2023]
Abstract
Heart rate responses to i.v. administration of cholecystokinin-8 (CCK-8) were investigated in Otsuka Long-Evans Tokushima Fatty (OLETF) rats lacking CCK-A receptors and control Long-Evans Tokushima Otsuka (LETO) rats. The heart rate decreased after i.v. administration of 3 nmol.kg(-)(1) of CCK-8 in LETO rats, but not in OLETF rats. Bradycardia in the LETO rats disappeared after treatment with MK-329, but not after treatment with L-365,260. The expression of CCK-A receptor precursor mRNA was found exclusively in the atrium in LETO rats. These results suggest that CCK-8 decreases heart rate via CCK-A receptors located in the atrium of the rats.
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MESH Headings
- Animals
- Benzodiazepinones/pharmacology
- Blotting, Southern
- Bradycardia
- DNA, Complementary/metabolism
- Devazepide/pharmacology
- Dose-Response Relationship, Drug
- Heart Atria/metabolism
- Heart Rate/drug effects
- Hormone Antagonists/pharmacology
- Male
- Phenylurea Compounds/pharmacology
- Polymerase Chain Reaction
- RNA, Messenger/metabolism
- Rats
- Rats, Inbred OLETF
- Rats, Long-Evans
- Receptor, Cholecystokinin A
- Receptors, Cholecystokinin/biosynthesis
- Receptors, Cholecystokinin/genetics
- Receptors, Cholecystokinin/physiology
- Sincalide/metabolism
- Sincalide/pharmacology
- Time Factors
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Affiliation(s)
- M Kurosawa
- Basic Medical Research Center, International University Health and Welfare, Otawara, Tochigi 324-8501, Japan.
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47
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Aoyama H, Shirato H, Nishioka T, Hashimoto S, Tsuchiya K, Kagei K, Onimaru R, Watanabe Y, Miyasaka K. Magnetic resonance imaging system for three-dimensional conformal radiotherapy and its impact on gross tumor volume delineation of central nervous system tumors. Int J Radiat Oncol Biol Phys 2001; 50:821-7. [PMID: 11395252 DOI: 10.1016/s0360-3016(01)01598-x] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.4] [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: 10/17/2022]
Abstract
PURPOSE We developed an MRI system for three-dimensional planning in radiotherapy. Its contribution on gross tumor volume (GTV) delineation of central nervous system (CNS) diseases was evaluated. METHODS AND MATERIALS The MRI system, with corrected distortion, was registered on computed tomography (CT) by means of fiducial/anatomic landmarks. In 41 consecutive patients with various CNS diseases, GTVs determined by MRI/CT registration (MR/CT-GTV) and CT alone (CT-GTV) were compared. Hard copies of diagnostic MRI were shown to doctors when CT-GTV was determined to simulate a conventional planning situation. Multi-observer volumetric analysis was conducted, assessing interobserver deviations among four radiation oncologists and intermethodological deviations between MR/CT-GTV and CT-GTV. RESULTS Overall, the mean of geometric distortion was significantly reduced from 1.08 mm to 0.3 mm by distortion correction (p < 0.0001). The contribution of the correction was apparent at >12.0 cm radius from the center of the magnetic field. Interobserver deviation was significantly reduced by MR/CT registration (p = 0.005). The improvement was significant for acoustic neurinoma (p = 0.038), astrocytomas (p = 0.043), and lesions at the cerebellum/brainstem (p = 0.008). The regression coefficient between MR/CT-GTV and CT-GTV was <0.9 for cerebellum/brainstem lesions, suggesting that MRI/CT-GTV was smaller than CT-GTV. CONCLUSIONS This system is feasible for three-dimensional planning and was shown to reduce interobserver deviations in GTV delineation for CNS diseases.
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Affiliation(s)
- H Aoyama
- Department of Radiology, Hokkaido University Graduate School of Medicine, Sapporo, Japan.
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48
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Abstract
We report magnetic resonance findings in the intramedullary schwannoma of the cervical spinal cord in two patients. In both cases, the solid portions of the tumours enhanced intensely after administration of Gd-DTPA and the enhanced border was sharply delineated from the adjacent spinal cord. Schwannomas should be considered in the differential diagnosis of intramedullary tumours when magnetic resonance images show a strongly enhancing mass with sharply delineated borders.
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Affiliation(s)
- Y Kodama
- Department of Radiology, Hokkaido University, School of Medicine, Sapporo, Japan.
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49
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Iiyori N, Miyasaka K, Kitahara Y, Uchida H, Takano H, Hattori F. [Radiological assessment of the structural relationship between the trachea and the innominate artery in physically disabled and scoliotic children]. Masui 2001; 50:766-9. [PMID: 11510068] [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: 02/21/2023]
Abstract
Studies were made on the physically disabled and scoliotic children who underwent tracheostomy. The purpose was to clarify factors that might lead to the tracheo-innominate artery fistula, by use of three-dimensional helical CT (3 DCT). In a case of right scoliosis, the tracheo-innominate artery fistula may be caused by the left-ward displacement of the trachea from the vertebra, having the innominate artery ride over the trachea and compressing it. In a case of the physically disabled and scoliotic children, there may be more compression on the trachea by the innominate artery along with the worsening scoliosis. Therefore, we consider it necessary to examine the structural relationship between the trachea, the vertebra, and the innominate artery periodically by 3 DCT.
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Affiliation(s)
- N Iiyori
- Department of Anesthesia, Chiba Children's Hospital, Chiba 266-0007
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50
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Sakamoto T, Shirato H, Takeichi N, Aoyama H, Fukuda S, Miyasaka K. Annual rate of hearing loss falls after fractionated stereotactic irradiation for vestibular schwannoma. Radiother Oncol 2001; 60:45-8. [PMID: 11410303 DOI: 10.1016/s0167-8140(01)00375-9] [Citation(s) in RCA: 22] [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] [Indexed: 11/29/2022]
Abstract
PURPOSE The rate of hearing loss in a population before and after irradiation was investigated to determine the effect of irradiation on hearing impairment. METHODS AND MATERIALS In 72 patients with vestibular schwannoma who received fractionated stereotactic irradiation from 1992 to 1999, 21 had had their hearing levels examined 3 months or more before the treatment. The mean time between the initial examination and treatment was 18.6 months (range: 3-89 months), and the mean time between treatment and the last follow-up was 24.2 months (12-69 months). Thirty-six to 50 Gy in 20-25 fractions over 5 to 6 weeks was given using an X-ray beam from a linear accelerator. Pure tone average (PTA) was measured using the mean hearing level at five frequencies, and the annual rate of hearing loss was defined as [(hearing loss in PTA(dB))/(follow-up period (months)x12)]. RESULTS The actual cumulative curve of decrease in tumor size of 2 mm or more was 38.3% at 2 years and 80.0% at 3 years. The mean of hearing loss in PTA was 11.6+/-10.3 dB (-1 to 35 dB) from the initial examination to the start of irradiation and 11.9+/-14.4 dB (-14 to 37 dB) from the start of irradiation to the last follow-up. The mean annual rates of hearing loss before irradiation and in the 1st,2nd,3rd and 4th years after irradiation were, respectively, 18.6, 11.2, 6.2, 5.1, and 5.0 dB/year. The annual rates of hearing loss in the 2nd year (P=0.025) and 3rd year (P=0.018) were significantly slower than the rate before irradiation. CONCLUSIONS The mean annual rate of hearing loss was higher before irradiation than after irradiation, and hearing loss slowed rather than accelerated after irradiation. Although hearing loss after the treatment was usually permanent, fractionated stereotactic irradiation was suggested to be effective to lower the rate of hearing loss.
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Affiliation(s)
- T Sakamoto
- Department of Otolaryngology, Hokkaido University School of Medicine, Sapporo, Japan
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