69 results on '"Michihata T"'
Search Results
2. Changing predictors of postoperative mortality in acute type A aortic dissection
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Hiroshi Takei, Tadanori Kawada, Yoshiharu Okada, Noboru Yamate, Shigeki Funaki, Toshihiro Takaba, Makoto Yamada, Shigeaki Sekiguchi, Michihata T, and Masahiro Aiba
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Adult ,Male ,medicine.medical_specialty ,Blood Vessel Prosthesis Implantation ,Risk Factors ,Internal medicine ,Cardiac tamponade ,medicine ,Humans ,Postoperative Period ,Myocardial infarction ,Coronary Artery Bypass ,Aortic rupture ,Aorta ,Aged ,Aged, 80 and over ,Aortic dissection ,Univariate analysis ,Cardiopulmonary Bypass ,business.industry ,Odds ratio ,Middle Aged ,medicine.disease ,Aortic Aneurysm ,Surgery ,Cardiac surgery ,Aortic Dissection ,Cardiothoracic surgery ,Acute Disease ,Cardiology ,Female ,Factor Analysis, Statistical ,Cardiology and Cardiovascular Medicine ,business - Abstract
Objectives: Rapid emergency transport and early diagnosis and surgical treatment for acute type A aortic dissection have improved postoperative survival, which has, however, plateaued at about 80%. End-organ malperfusion is regarded as a strong predictor of postoperative mortality, replacing factors such as cardiac tamponade complications, aortic rupture, and left ventricular dysfunction due to aortic insufficiency. It is thus important to reevaluate risk factors for surgical death to assess current therapeutic strategies.Methods: We statistically analyzed potential risk factors for perioperative death in 88 patients undergoing surgical repair for type A aortic dissection between January 1990 and December 1999.Results: Univariate analysis showed that cardiopulmonary arrest (adjusted odds ratio: 13.78; p
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- 2001
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3. Congenital Bicuspid Aortic Stenosis in Siblings
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Toshihiro Takaba, Masato Kume, Michihata T, Kazuhiro Morimoto, Toshitaka Kashima, and Masahiro Aiba
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Thesaurus (information retrieval) ,medicine.medical_specialty ,Stenosis ,business.industry ,General surgery ,medicine ,business ,medicine.disease - Abstract
当施設では, これまで22例の先天性大動脈二尖弁の症例を経験しているが, 今回同胞に発生した大動脈二尖弁狭窄を経験し, 文献上検索したかぎり1例の報告も認められなかったので報告する. 症例は兄58歳, 妹56歳であり, 兄は51歳時, 妹は15歳時より心臓弁膜症を指摘されていた. 両者とも大動脈二尖弁狭窄の診断にて21mm Medtronic-Hall 弁にて大動脈弁置換術を施行し, さらに妹ではペースメーカー植込み術を追加した. 術後経過は両者とも良好である. 先天性大動脈二尖弁は遺伝的な関係が関与するため, 発見されたなら, 家族内および親族の精査が必要であろうと考えられる.
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- 1993
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4. Nutrition, inflammation and oxidative stress - CKD 1-5
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Susla, O., primary, Shin, H. S., additional, Jung, Y. S., additional, Rim, H., additional, Speer, T., additional, Owala, F. O., additional, Razawi, M., additional, Holy, E., additional, Ferdinand, B., additional, Danilo, F., additional, Luscher, T. F., additional, Tanner, F. C., additional, Markaki, A., additional, Kyriazis, J., additional, Petrakis, I., additional, Mavroeidi, V., additional, Perakis, K., additional, Fragkiadakis, G. A., additional, Venyhaki, M., additional, Tzanakakis, M., additional, Vardaki, E., additional, Maraki, K., additional, Doskas, T., additional, Daphnis, E., additional, Bregman, R., additional, Vale, B., additional, Lemos, C., additional, Kawakami, L., additional, Silva, M. I., additional, Zhu, F., additional, Kaysen, G., additional, Kotanko, P., additional, Abbas, S. R., additional, Dou, Y., additional, Heymsfield, S., additional, Levin, N. W., additional, Turkmen, K., additional, Kayikcioglu, H., additional, Guney, I., additional, Altintepe, L., additional, Ozbek, O., additional, Tonbul, H. Z., additional, Kaysen, G. A., additional, Usvyat, L. A., additional, Thijssen, S., additional, Mutluay, R., additional, Konca Degertekin, C., additional, Derici, U., additional, Yilmaz, M. I., additional, Akkiyal, F., additional, Gultekin, S., additional, Gonen, S., additional, Deger, S. M., additional, Arinsoy, T., additional, Sindel, S., additional, Hueso, M., additional, Torras, J., additional, Carrera, M., additional, Vidal, A., additional, Navarro, E., additional, Rivas, I., additional, Rama, I., additional, Bolanos, N., additional, Varela, C., additional, Martinez-Castelao, A., additional, Grinyo, J. M., additional, Harving, F., additional, Svensson, M., additional, Schmidt, E. B., additional, Jorgensen, K. A., additional, Christensen, J. H., additional, Park, J. H., additional, Koo, E. H., additional, Kim, H. K., additional, Kim, M. S., additional, Cho, A. J., additional, Lee, J. E., additional, Jang, H. R., additional, Huh, W., additional, Kim, D. J., additional, Kim, Y.-G., additional, Oh, H. Y., additional, Zawiasa, A., additional, Nowak, D., additional, Nowicki, M., additional, Nathalie, N., additional, Griet, G., additional, Eva, S., additional, Raymond, V., additional, Ng, K. P., additional, Stringer, S., additional, Jesky, M., additional, Dutton, M., additional, Ferro, C., additional, Cockwell, P., additional, Jia, T., additional, Gama Axelsson, T., additional, Lindholm, B., additional, Heimburger, O., additional, Barany, P., additional, Stenvinkel, P., additional, Qureshi, A. R., additional, Quiroga, B., additional, Goicoechea, M., additional, Garcia de Vinuesa, S., additional, Verdalles, U., additional, Reque, J., additional, Panizo, N., additional, Arroyo, D., additional, Santos, A., additional, Macias, N., additional, Luno, J., additional, Honda, H., additional, Hirano, T., additional, Ueda, M., additional, Kojima, S., additional, Mashiba, S., additional, Hayase, Y., additional, Michihata, T., additional, Akizawa, T., additional, Gungor, O., additional, Sezis Demirci, M., additional, Kircelli, F., additional, Tatar, E., additional, Hur, E., additional, Sen, S., additional, Toz, H., additional, Basci, A., additional, Ok, E., additional, Sepe, V., additional, Albrizio, P., additional, Gnecchi, M., additional, Cervio, E., additional, Esposito, P., additional, Rampino, T., additional, Libetta, C., additional, Dal Canton, A., additional, Faria, M. S., additional, Ribeiro, S., additional, Silva, G., additional, Nascimento, H., additional, Rocha-Pereira, P., additional, Miranda, V., additional, Vieira, E., additional, Santos, R., additional, Mendonca, D., additional, Quintanilha, A., additional, Costa, E., additional, Belo, L., additional, Santos-Silva, A., additional, Pruijm, M., additional, Hofmann, L., additional, Heuvelin, E., additional, Forni, V., additional, Coristine, A., additional, Stuber, M., additional, Vogt, B., additional, Burnier, M., additional, Chiappini, M. G., additional, Ammann, T., additional, Muzzi, L., additional, Grosso, A., additional, Sabry, A., additional, Bansal, V., additional, Hoppensteadt, D., additional, Jeske, W., additional, and Fareed, J., additional
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- 2012
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5. Channel capacity enhancement by polarization and pattern of access point antenna in indoor MIMO systems
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Uchida, D., primary, Michihata, T., additional, Arai, H., additional, Inoue, Y., additional, and Cho, K., additional
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- 2008
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6. Quantitative measurement of rigional myocardial blood flow in patients with coronary artery stenosis by intravenous injection of 13N-annmonia in positron emission tomography.
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Michihata, T., primary
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- 1991
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7. Hemodynamic and clinical evaluation of the 19mm mechanical prosthesis. Two different procedure of the aortic annular enlargement (Nicks' vs Liotta's).
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Michihata, T., primary
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- 1990
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8. Exercise-induced ST-segment changes permit prediction of improvement in left ventricular ischemic dysfunction after revascularization: evaluation with positron emission tomographic measurements of regional myocardial blood flow and cardiac output.
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Watanabe, Takuya, Harumi, Kenichi, Michihata, Tetsuo, Okazaki, Osamu, Yamanaka, Hideyuki, Akutsu, Yasushi, Katagiri, Takashi, Watanabe, T, Harumi, K, Michihata, T, Okazaki, O, Yamanaka, H, Akutsu, Y, and Katagiri, T
- Abstract
Background: Prediction of the recovery of left ventricular (LV) ischemic dysfunction after revascularization is important in patients with coronary artery disease (CAD). We investigated whether the improvement in LV ischemic dysfunction after revascularization could be predicted preoperatively by exercise-induced ST-segment changes.Methods and Results: Regional myocardial blood flow (RMBF) and cardiac output were measured with nitrogen 13-ammonia positron emission tomography at rest and during low-level exercise in 28 patients with angiographically proven CAD before and after successful revascularization and in 9 normal subjects. Before revascularization, exercise-induced upsloping ST-segment depression <1 mm 80 msec after the J-point was observed in 11 patients (group 1), horizontal depression of 1 to 1.5 mm was observed in 9 patients (group 2), and downsloping depression > or =1.5 mm was observed in 8 patients (group 3). The number of regions of critical CAD was greater in group 3 than in groups 1 and 2 (3.6 +/- 1.4 vs 1.6 +/- 0.7 and 2.2 +/- 1.1, p < 0.001, p < 0.02). Increase of RMBF in regions of critical CAD with exercise was lower in group 3 than in groups 1 and 2 (0.15 +/- 0.01 vs 0.22 +/- 0.01 and 0.18 +/- 0.02 ml/min per gram, p < 0.0001, p < 0.01). After revascularization, RMBF in regions of critical CAD both at rest and during exercise improved in groups 1 (0.49 +/- 0.15 to 0.60 +/- 0.18, 0.70 +/- 0.26 to 0.86 +/- 0.33 ml/min per gram, both p < 0.05) and 2 (0.50 +/- 0.15 to 0.62 +/- 0.19, 0.67 +/- 0.26 to 0.89 +/- 0.31 ml/min per gram, both p < 0.02), but was unchanged in group 3 (0.47 +/- 0.09 to 0.47 +/- 0.15, 0.62 +/- 0.17 to 0.64 +/- 0.23 ml/min per gram, both p = NS). Cardiac output at rest improved in groups 1 (4.98 +/- 0.43 to 5.35 +/- 0.50 L/min, p < 0.02) and 2 (5.08 +/- 0.52 to 5.53 +/- 0.28 L/min, p < 0.02), but was unchanged in group 3 (4.76 +/- 0.48 to 4.88 +/- 0.82 L/min, p = NS).Conclusions: Our results suggest that marked downsloping ST-segment depression induced by preoperative low-level exercise may predict a lack of improvement in LV ischemic dysfunction after revascularization. [ABSTRACT FROM AUTHOR]- Published
- 1998
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9. Neuroblastoma mass screening in infancy in Kyoto, Japan.
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Sawada, Tadashi, Kawakatsu, Hidekazu, Sugimoto, Tohru, Horii, Yoshihiro, Kuroda, Keiji, Hosoi, Hajime, Saida, Tohru, Hino, Tamaki, Michihata, Takashi, Sawada, T, Kawakatsu, H, Sugimoto, T, Horii, Y, Kuroda, K, Hosoi, H, Saida, T, Hino, T, and Michihata, T
- Abstract
In this paper, we introduced our mass screening system for NB in Kyoto, which is useful for early detection of NB and is expected to improve the survival rate of these patients. In addition to the beneficial results, we discussed several problems associated with the NB-mass sceening program. The NB-mass screening system can be adapted for use all over the world as a useful and simple detection method comparable to phenylketonuria, galactosemia tests, such as several inborn errors of meatbolism. [ABSTRACT FROM AUTHOR]
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- 1987
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10. Intrathecal Administration of Human Leukocyte Interferon to a Patient with Subacute Sclerosing Panencephalitis
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NAKAGAWA, M., primary, MICHIHATA, T., additional, YOSHIOKA, H., additional, SAWADA, T., additional, KUSUNOKI, T., additional, and KISHIDA, T., additional
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- 1985
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11. 25 Clinical experience with intraaortic balloon pump support in valve replacement and ischemic heart surgery
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Michihata, T., primary
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- 1986
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12. Functional role of coronary collaterals with exercise in infarct-related myocardium
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Akutsu, Y., Hara, T., Michihata, T., and Watanabe, T.
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- 1995
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13. Relation between exercise-induced myocardial ischemia as assessed by nitrogen-13 ammonia positron emission tomography and QT interval behavior in patients with right bundle branch block.
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Watanabe, Takuya, Harumi, Kenichi, Akutsu, Yasushi, Yamanaka, Hideyuki, Michihata, Tetsuo, Okazaki, Osamu, Katagiri, Takashi, Watanabe, T, Harumi, K, Akutsu, Y, Yamanaka, H, Michihata, T, Okazaki, O, and Katagiri, T
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CORONARY heart disease risk factors , *EXERCISE physiology - Abstract
Exercise-induced myocardial ischemia is difficult to detect with ST-T changes in patients with right bundle branch block (RBBB). We sought to predict exercise-induced myocardial ischemia with QT interval behavior during exercise in patients with RBBB. Twenty-two patients with angiographically proven coronary artery disease and RBBB and 9 healthy volunteers underwent nitrogen-13 ammonia positron emission tomography with bicycle ergometer exercise at a fixed workload of 25 W. Regional myocardial blood flow (RMBF) and electrocardiographic changes were measured both at rest and after 5 minutes of exercise. The QT interval was measured from the onset of the QRS complex to the offset of the T wave in lead V5. The deltaQT and deltaRMBF, which indicated values after 5 minutes of exercise minus values at rest, were negatively correlated (r = -0.74, p <0.001). Exercise-induced shortening of the QT interval (422 +/- 27 to 381 +/- 38 ms, p = 0.0020) was observed in 15 patients (group 1) and no change or prolongation (411 +/- 45 to 420 +/- 37 ms, p = NS) was observed in 7 patients (group 2). Multivessel disease was significantly more frequent but collateral circulation was significantly less in group 2 than in group 1 (p <0.01, p <0.05, respectively). Cardiac output at rest was significantly lower in groups 1 and 2 than in healthy volunteers (4.52 +/- 0.83 and 4.51 +/- 0.84 vs 6.20 +/- 0.83 L/min; p = 0.0014, p = 0.0003). Although RMBF at rest did not differ significantly among groups 1 and 2 and healthy volunteers (0.63 +/- 0.20 vs 0.69 +/- 0.13 and vs 0.77 +/- 0.14 ml/min/g), RMBF after 5 minutes of exercise was significantly lower in group 2 than in group 1 and healthy volunteers (0.78 +/- 0.11 vs 0.96 +/- 0.20 and vs 1.20 +/- 0.18 ml/min/g; p = 0.0289, p <0.0001). The number of regions of critical coronary artery disease was significantly greater in group 2 than in group 1 (4.0 +/- 1.2 vs 2.1 +/- 1.3, p = 0.0039). Our results suggest that the absence of QT interval shortening during exercise may indicate severe myocardial ischemia induced by exercise in patients with RBBB and coronary artery disease. [ABSTRACT FROM AUTHOR]
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- 1998
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14. Erythropoiesis stimulating agents are associated with serum fibroblast growth factor 23 metabolism in patients on hemodialysis.
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Honda H, Tanaka K, Michihata T, Shibagaki K, Yuza T, Hirao K, Tomosugi N, Ganz T, and Higashimoto Y
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Background: This study aimed to determine associations among short- and long-acting erythropoiesis stimulating agents (ESAs), changes in serum fibroblast growth factor 23 (FGF23) and biomarkers of iron metabolism., Methods: Among 108 patients on hemodialysis (HD), 44 received every 2 weeks or monthly doses of continuous erythropoiesis receptor activator (CERA), 31 received weekly doses of darbepoetin-α, 24 received three doses per week of epoetin-β and 9 were not treated with an ESA. Intact and C-terminal FGF23 and transferrin saturation (TSAT), ferritin, erythroferrone and hepcidin 25 were measured in blood samples collected before the HD session at the end of the dialysis week (baseline, Day 0) and on Days 3, 5, 7 and 14 thereafter., Results: Levels of ferritin, hepcidin 25 and erythroferrone as well as TSAT were significantly decreased or elevated in patients treated with CERA compared with other types of ESAs. Levels of C-terminal FGF23 increased in all groups during the observation period. Levels of intact FGF23 and ratios of intact FGF23 to C-terminal FGF23 gradually decreased between Days 3 and 7 in the CERA but not in the other groups. Multivariate models associated changes in hepcidin 25 and phosphate with those of intact FGF23., Conclusion: The long-acting ESA CERA might influence levels of intact FGF23 by increasing FGF23 cleavage in patients on HD in association with prolonged hepcidin 25 suppression., (© The Author(s) 2020. Published by Oxford University Press on behalf of ERA-EDTA.)
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- 2020
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15. Chemical, Microbiological, and Functional Characterization of Kefir Produced from Cow's Milk and Soy Milk.
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Gamba RR, Yamamoto S, Abdel-Hamid M, Sasaki T, Michihata T, Koyanagi T, and Enomoto T
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Kefir is a functional beverage that contains lactic and acetic acid bacteria (LAB, AAB) and yeasts. This work's aim was to study the chemical, microbial, and functional characteristics of kefir produced from cow's milk and soy milk. After fermentation, free amino acids were 20.92 mg 100 mL
-1 and 36.20 mg 100 mL-1 for cow's milk and soy milk kefir, respectively. Glutamic acid was majority in both, suggesting that microbial proteolysis leads to an increase in free amino acids including glutamic acid. 108 -109 CFU mL-1 LAB, 106 -107 CFU mL-1 AAB, and 106 -107 CFU mL-1 yeasts were counted in cow's milk kefir, whereas soy milk kefir contained greatly lower yeasts and AAB. Lactococcus lactis , Kazachstania unispora , and Saccharomyces cerevisiae were isolated as major microorganisms in both kefirs. Acetobacter orientalis only existed in cow's milk kefir. Cow's milk and soy milk showed ACE inhibitory activity, which significantly increased after fermentation. Both kefirs also exhibited antioxidant activity and bactericidal activity against Escherichia coli , Salmonella Typhimurium, and Staphylococcus aureus ., Competing Interests: The authors declare that they have no conflicts of interest., (Copyright © 2020 Raúl Ricardo Gamba et al.)- Published
- 2020
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16. In vitro antioxidant, anti-glycation and immunomodulation activities of fermented blue-green algae Aphanizomenon flos-aquae.
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Taniguchi M, Kuda T, Shibayama J, Sasaki T, Michihata T, Takahashi H, and Kimura B
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- Animals, Antioxidants pharmacology, Cyanobacteria metabolism, Dietary Supplements, Fermentation drug effects, Glycosylation drug effects, Immunomodulation drug effects, Japan, Mice, Oxidative Stress drug effects, Oxidative Stress physiology, Aphanizomenon metabolism, Aphanizomenon physiology, RAW 264.7 Cells drug effects
- Abstract
To clarify the antioxidant, anti-glycation and immunomodulatory capacities of fermented blue-green algae Aphanizomenon flos-aquae (AFA), hot aqueous extract suspensions made from 10% AFA were fermented by Lactobacillus plantarum AN7 and Lactococcus lactis subsp. lactis Kushiro-L2 strains isolated from a coastal region of Japan. The DPPH and O
2 - radical scavenging capacities and Fe-reducing power were increased in the fermented AFA. The increased DPPH radical scavenging capacity of the fermented AFA was fractionated to mainly < 3 kDa and 30-100 kDa. The increased O2 - radical scavenging capacities were fractionated to mainly < 3 kDa. Anti-glycation activity in BSA-fructose model rather than BSA-methylglyoxal model was increased by the fermentation. The increased anti-glycation activity was fractionated to mainly 30-100 kDa. The NO concentration in the murine macrophage RAW264.7 culture media was high with the fermented AFA. The increased immunomodulation capacity was also fractionated to mainly 30-100 kDa. These results suggest that the fermented AFA is a more useful material for health foods and supplements.- Published
- 2019
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17. Differential Impacts of Intravenous Iron Administration and Iron-Containing Phosphate Binders on Serum Intact Fibroblast Growth Factor 23 Levels.
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Honda H, Tanaka K, Michihata T, Shibagaki K, Yuza T, Hirao K, Tomosugi N, and Shibata T
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- Administration, Intravenous, Aged, Anemia blood, Anemia drug therapy, Anemia etiology, Female, Fibroblast Growth Factor-23, Hematinics therapeutic use, Humans, Iron administration & dosage, Male, Middle Aged, Renal Insufficiency, Chronic complications, Fibroblast Growth Factors blood, Iron therapeutic use, Phosphates blood, Renal Dialysis adverse effects, Renal Insufficiency, Chronic blood, Renal Insufficiency, Chronic therapy
- Abstract
Aims: This study assessed the impact of iron administration on serum fibroblast growth factor 23 (FGF23) levels., Methods: Of 123 hemodialysis (HD) patients treated with erythropoiesis-stimulating agents, 22 received once-weekly intravenous iron and 17 received daily oral iron with iron-containing phosphate binders. Intact FGF23 and biomarkers of iron metabolism were measured from blood samples drawn before each HD session, at baseline and on days 3, 5, 7, and 14., Results: Phosphate levels did not differ among the 3 groups during the 14-day period. Ferritin levels were significantly increased in both iron treatment groups compared with the non-iron treatment group, but changes in transferrin saturation levels were similar in the intravenous iron and non-iron groups. However, intact FGF23 levels were continuously higher in the intravenous iron group than those in the other groups., Conclusion: Intravenous iron administration may influence intact FGF23 levels in HD patients independently of phosphate and iron metabolism., (© 2019 S. Karger AG, Basel.)
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- 2019
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18. Associations among apolipoproteins, oxidized high-density lipoprotein and cardiovascular events in patients on hemodialysis.
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Honda H, Hirano T, Ueda M, Kojima S, Mashiba S, Hayase Y, Michihata T, Shishido K, Takahashi K, Hosaka N, Ikeda M, Sanada D, and Shibata T
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- Adult, Aged, Aged, 80 and over, C-Reactive Protein analysis, Cardiovascular Diseases mortality, Female, Follow-Up Studies, Humans, Interleukin-6 blood, Lipids blood, Lipoproteins, LDL blood, Male, Middle Aged, Prospective Studies, Risk Factors, Survival Rate, Apolipoproteins blood, Cardiovascular Diseases blood, Lipoproteins, HDL blood, Renal Dialysis
- Abstract
Apolipoproteins are associated with survival among patients on hemodialysis (HD), but these associations might be influenced by dysfunctional (oxidized) high-density lipoprotein (HDL). We assessed associations among apolipoproteins and oxidized HDL, mortality and cardiovascular disease (CVD) events in patients on HD. This prospective observational study examined 412 patients on prevalent HD. Blood samples were obtained before dialysis at baseline to measure lipids, apolipoproteins, oxidized LDL, oxidized HDL, high-sensitivity C-reactive protein (hs-CRP) and interleukin (IL)-6 at baseline, and HDL-C and hs-CRP were measured 12 months later. Patients were then prospectively followed-up (mean, 40 months) and all-cause mortality and composite CVD events were analyzed. Associations between variables at baseline and clinical outcome were assessed by Cox proportional hazards modeling (n = 412) and Cox hazards modeling with a time-varying covariate with HDL-C and hs-CRP (n = 369). Quartiles of apolipoproteins and oxidized HDL were not associated with all-cause mortality. However, Cox proportional hazards models with quartiles of each variable adjusted for confounders and hs-CRP or IL-6 identified apolipoprotein (apo)B-to-apoA-I ratio (apoB/apoA-I) and oxidized HDL, but not apoA-I or apoA-II, as independent risk factors for composite CVD events. These associations were confirmed by Cox proportional hazards modeling with time-varying covariates for hs-CRP. ApoB/apoA-I was independently associated with composite CVD events in 1-standard deviation (SD) increase-of-variables models adjusted for the confounders, oxidized HDL and hs-CRP. However, these associations disappeared from the model adjusted with IL-6 instead of hs-CRP, and oxidized HDL and IL-6 were independently associated with composite CVD events. Findings resembled those from Cox proportional hazards modeling using time-varying covariates with HDL-C adjusted with IL-6. In conclusion, both oxidized HDL and apoB/apoA-I might be associated with CVD events in patients on prevalent HD, while associations of apoB/apoA-I with CVD events differed between models of apoB/apoA-I quartiles and 1-SD increases, and were influenced by IL-6.
- Published
- 2017
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19. High fibroblast growth factor 23 levels are associated with decreased ferritin levels and increased intravenous iron doses in hemodialysis patients.
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Honda H, Michihata T, Shishido K, Takahashi K, Takahashi G, Hosaka N, Ikeda M, Sanada D, and Shibata T
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- Aged, Female, Fibroblast Growth Factor-23, Humans, Infusions, Intravenous, Male, Middle Aged, Prospective Studies, Ferritins blood, Fibroblast Growth Factors metabolism, Iron administration & dosage, Renal Dialysis
- Abstract
A recent study demonstrated the association between inflammation, iron metabolism and fibroblast growth factor (FGF) 23. The present clinical study aimed to assess associations between anemia, iron metabolism and FGF23 in hemodialysis (HD) patients. This prospective observational study examined a cohort of prevalent HD patients (n = 282). Blood samples were obtained before dialysis sessions to measure baseline levels of hemoglobin (Hb), transferrin saturation (TSAT), ferritin, albumin-adjusted calcium (Ca), phosphate (P), intact (i)-PTH, 25-hydroxyvitamin D, 1,25-dihydroxyvitamin D, intact (i)-FGF23, high sensitive (hs)-CRP, and interleukin-6. After the baseline measurement, study patients were followed-up for 6 months. Biochemical measurements were subsequently performed at 1 (Hb), 2 (TSAT and ferritin) or 3 (Ca, P and hs-CRP) month intervals. Doses of ESAs and intravenous iron supplementation during the study period were recorded. i-FGF23 was positively correlated with Ca, P, i-PTH and inversely correlated with TSAT and ferritin. However, levels of Hb and hs-CRP and doses of ESAs during the study period did not differ among the i-FGF23 tertiles, with levels of ferritin and TSAT in the higher i-FGF23 tertile being consistently lower than in the middle to lower i-FGF23 tertiles. Multivariate repeated measures analysis indicated that the higher i-FGF23 tertile was independently associated with repeated measurements of ferritin, but not of TSAT. Doses of intravenous iron supplementation were significantly increased in the higher i-FGF23 tertile in multivariate models. In conclusion, high i-FGF23 levels may be associated with prolongation of low levels of ferritin, resulting in increased usages of iron supplementation in HD patients.
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- 2017
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20. Characterisation of odorants in roasted stem tea using gas chromatography-mass spectrometry and gas chromatography-olfactometry analysis.
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Sasaki T, Koshi E, Take H, Michihata T, Maruya M, and Enomoto T
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- Plant Stems chemistry, Chromatography, Gas methods, Gas Chromatography-Mass Spectrometry methods, Odorants analysis, Olfactometry methods, Tea chemistry
- Abstract
Roasted stem tea has a characteristic flavour, which is obtained by roasting tea stems, by-product of green tea production. This research aims to understand the characteristic odorants in roasted stem tea by comparing it to roasted leaf tea. We revealed potent odorants in commercial roasted stem tea using gas chromatography-mass spectrometry (GC-MS) and gas chromatography-olfactometry with aroma extract dilution analysis (AEDA). The difference between roasted stem and leaf tea derived from the same tea plants were investigated using GC-MS. Pyrazine compounds exhibited a roasted odour and high flavour dilution (FD) factors, as determined via AEDA. Roasted stem tea was richer in these pyrazines than roasted leaf tea. Geraniol and linalool exhibited high FD factors and a floral odour, and roasted stem tea was richer in these compounds than roasted leaf tea. These results may have a positive impact on the development of tea products., (Copyright © 2016 Elsevier Ltd. All rights reserved.)
- Published
- 2017
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21. The γ-aminobutyric acid-producing ability under low pH conditions of lactic acid bacteria isolated from traditional fermented foods of Ishikawa Prefecture, Japan, with a strong ability to produce ACE-inhibitory peptides.
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Barla F, Koyanagi T, Tokuda N, Matsui H, Katayama T, Kumagai H, Michihata T, Sasaki T, Tsuji A, and Enomoto T
- Abstract
Many traditional fermented products are onsumed in Ishikawa Prefecture, Japan, such as kaburazushi , narezushi , konkazuke , and ishiru. Various kinds of lactic acid bacteria (LAB) are associated with their fermentation, however, characterization of LAB has not yet been elucidated in detail. In this study, we evaluated 53 isolates of LAB from various traditional fermented foods by taxonomic classification at the species level by analyzing the 16S ribosomal RNA gene (rDNA) sequences and carbohydrate assimilation abilities. We screened isolates that exhibited high angiotensin-converting enzyme (ACE) inhibitory activities in skim milk or soy protein media and produced high γ-aminobutyric acid (GABA) concentrations in culture supernatants when grown in de Man Rogosa Sharpe broth in the presence of 1% (w/v) glutamic acid. The results revealed that 10 isolates, i.e., Lactobacillus buchneri (2 isolates), Lactobacillus brevis (6 isolates), and Weissella hellenica (2 isolates) had a high GABA-producing ability of >500 mg/100 ml after 72 h of incubation at 35 °C. The ACE inhibitory activity of the whey cultured with milk protein by using L. brevis (3 isolates), L. buchneri (2 isolates), and W. hellenica (2 isolates) was stronger than that of all whey cultured with soy protein media, and these IC
50 were < 1 mg protein/ml. Three of 10 isolates had high GABA-producing activities at pH 3, suggesting that they could be powerful candidates for use in the fermentation of food materials having low pH.- Published
- 2016
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22. High-Density Lipoprotein Subfractions and Their Oxidized Subfraction Particles in Patients with Chronic Kidney Disease.
- Author
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Honda H, Hirano T, Ueda M, Kojima S, Mashiba S, Hayase Y, Michihata T, and Shibata T
- Subjects
- Aged, Apolipoprotein A-I blood, Cholesterol, HDL blood, Cholesterol, LDL blood, Cross-Sectional Studies, Female, Humans, Inflammation, Male, Malondialdehyde chemistry, Middle Aged, Multivariate Analysis, Oxidative Stress, Proportional Hazards Models, Prospective Studies, Risk Factors, Lipoproteins, HDL blood, Oxygen chemistry, Renal Insufficiency, Chronic blood
- Abstract
Aim: Chronic kidney disease (CKD) may lead to reduced concentrations of high-density lipoprotein (HDL) and its subfractions (HDL2 and HDL3), and damage them via inflammation and oxidative stress. The present study aimed to determine the contribution of such changes to cardiovascular disease (CVD) in patients with CKD., Methods: The levels of total cholesterol, low-density lipoprotein cholesterol, HDL-C, HDL2, HDL3, apolipoproteins, malondialdehyde-modified LDL (MDA-LDL), oxidized (ox) HDL, oxHDL2, and oxHDL3 were measured in blood samples from patients with CKD (stages 2-5, n=86) who were not on dialysis and from patients undergoing hemodialysis (CKD stage 5D, n=25). The patients were followed up for 28±9 months after baseline examinations and CVD events were recorded., Result: The levels of HDL3 and ApoA1 in HDL3 fraction decreased according to CKD severity, whereas those of HDL2 and ApoA1 in HDL2 fraction did not differ. The levels of oxHDL were similar across CKD stages. The levels of oxHDL3 and MDA-LDL were decreased, whereas those of oxHDL2 increased according to CKD severity. Multivariate analyses using the Cox proportional hazards model selected high levels of oxHDL and its subfractions, and those adjusted with HDL-C and HDL subfractions or ApoA1 in HDL fractions respectively, compared with HDL-C and HDL subfractions or ApoA1 in HDL fractions alone as independent risk factors for CVD events., Conclusion: The levels of HDL subfractions and their oxidized subfraction particles differed among patients with CKD. The increasing levels of oxHDL subfractions might cause a high frequency of CVD events in such patients.
- Published
- 2016
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23. Effects of Long-Term Erythropoiesis-Stimulating Agents on Iron Metabolism in Patients on Hemodialysis.
- Author
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Onuma S, Honda H, Kobayashi Y, Yamamoto T, Michihata T, Shibagaki K, Yuza T, Hirao K, Tomosugi N, and Shibata T
- Subjects
- Aged, Biomarkers blood, Female, Hepcidins blood, Humans, Male, Middle Aged, Transferrin metabolism, Darbepoetin alfa therapeutic use, Erythropoietin therapeutic use, Hematinics therapeutic use, Iron metabolism, Polyethylene Glycols therapeutic use, Renal Dialysis
- Abstract
Continuous erythropoietin receptor activator (CERA) and darbepoetin-α (DA) might differently affect iron metabolism and erythropoiesis in patients on hemodialysis (HD). This prospective study examined a cohort of patients on HD who had received either intravenous CERA every 2 or 4 weeks (N = 25) or DA once each week (N = 47). Blood was sampled before HD sessions on days 0, 2, 4, 7 and 14, and on days 0, 3, 5, 7 and 14 from patients who were injected with ESA at the beginning and end of the dialysis week, respectively. Changes in factors indicating erythropoiesis and biomarkers of iron metabolism were examined. Hemoglobin levels were maintained in the target range between 10.0 and 11.0 g/dL and ferritin levels at baseline and during the study period were similar between the DA and CERA groups. Levels of hepcidin 25 decreased from days 2-3 to day 5 and returned to the baseline at day 7 in the DA group, whereas those and transferrin saturation were serially suppressed from days 2-3 to day 14 in the CERA group. Levels of soluble transferrin receptor and reticulocyte counts were significantly elevated from days 4-5 to day 14 by CERA. Both DA and CERA stabilized erythropoiesis, but CERA might mobilize iron from body stores more effectively than DA in patients on HD., (© 2015 International Society for Apheresis, Japanese Society for Apheresis, and Japanese Society for Dialysis Therapy.)
- Published
- 2015
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24. Removal of cadmium from fish sauce using chelate resin.
- Author
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Sasaki T, Araki R, Michihata T, Kozawa M, Tokuda K, Koyanagi T, and Enomoto T
- Subjects
- Adsorption, Amino Acids analysis, Animals, Cadmium chemistry, Nutritive Value, Cadmium isolation & purification, Chelating Agents chemistry, Fish Products analysis, Food Contamination analysis, Resins, Synthetic chemistry
- Abstract
Fish sauce that is prepared from squid organs contains cadmium (Cd), which may be present at hazardous concentrations. Cd molecules are predominantly protein bound in freshly manufactured fish sauce, but are present in a liberated form in air-exposed fish sauce. In the present study, we developed a new method for removing both Cd forms from fish sauce using chelate resin and a previously reported tannin treatment. Sixteen-fold decreases in Cd concentrations were observed (0.78-0.05 mg/100 mL) following the removal of liberated Cd using chelate resin treatment, and the removal of protein-bound Cd using tannin treatment. Major nutritional components of fish sauce were maintained, including free amino acids and peptides, and angiotensin I-converting enzyme inhibitory and antioxidant activities., (Copyright © 2014 Elsevier Ltd. All rights reserved.)
- Published
- 2015
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25. Active vitamin D analogs, maxacalcitol and alfacalcidol, as maintenance therapy for mild secondary hyperparathyroidism in hemodialysis patients - a randomized study.
- Author
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Honda H, Koiwa F, Ogata H, Shishido K, Sekiguchi T, Michihata T, Ogawa H, Mukai M, Takahashi K, Suzuki R, Kino K, Kato K, Yamamoto K, Kinugasa E, and Akizawa T
- Subjects
- Aged, Biomarkers blood, Calcitriol adverse effects, Calcitriol therapeutic use, Calcium blood, Drug Substitution, Female, Humans, Hydroxycholecalciferols adverse effects, Hyperparathyroidism, Secondary blood, Hyperparathyroidism, Secondary etiology, Japan, Male, Middle Aged, Parathyroid Hormone blood, Phosphates blood, Prospective Studies, Renal Insufficiency, Chronic blood, Renal Insufficiency, Chronic complications, Time Factors, Treatment Outcome, Vitamins adverse effects, Calcitriol analogs & derivatives, Hydroxycholecalciferols therapeutic use, Hyperparathyroidism, Secondary drug therapy, Renal Dialysis adverse effects, Renal Insufficiency, Chronic therapy, Vitamins therapeutic use
- Abstract
Background: The present randomized study was designed to compare the efficacy between two active vitamin D analogs, alfacalcidol (ACD) and maxacalcitol (OCT), for the management of mild secondary hyperparathyroidism (SHPT) in dialysis patients., Methods: SHPT in all 32 patients analyzed in the study was initially treated with OCT. Once patients' intact PTH levels decreased to the target range of 150 - 180 pg/mL, they were randomized either to switch to ACD at 0.5 μg/day (n = 14), or to remain on an effectively unchanged dose of OCT (n = 13). Phosphate, calcium, and intact PTH levels were measured every 2 weeks for 12 weeks and vitamin D doses were changed according to target ranges of phosphate (3.5 - 6.0 mg/dL), calcium (albuminadjusted calcium: 8.4 - 10.0 mg/dL), and intact parathyroid hormone (60 - 180 pg/mL). Achievement rates of the target ranges of the parameters were estimated., Results: Baseline calcium levels in the OCT group were significantly higher than in the ACD group. Changes in achievement rates of target ranges of intact PTH and calcium during the study did not differ significantly between the vitamin D drugs. Changes in calcium levels in the OCT and ACD groups were similar during the study. Achievement rates of the target range of phosphate in both groups were also similar until 8 weeks, although the rate in the OCT group declined at 10 weeks., Conclusions: The efficacy and safety of OCT for the treatment of mild SHPT are similar to those of ACD in hemodialysis patients.
- Published
- 2014
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26. Microbial and chemical properties of Cambodian traditional fermented fish products.
- Author
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Chuon MR, Shiomoto M, Koyanagi T, Sasaki T, Michihata T, Chan S, Mao S, and Enomoto T
- Subjects
- Acetic Acid analysis, Animals, Cambodia, Fish Products microbiology, Flavoring Agents, Humans, Lactic Acid analysis, RNA, Ribosomal, 16S genetics, Shellfish microbiology, Bacteria genetics, Diet, Fermentation, Fish Products analysis, Food Microbiology, Shellfish analysis, Sodium Chloride analysis
- Abstract
Background: Fermented fish products, commonly consumed in south-east Asia, are used as condiments that contribute to people's nutritional sources and as seasonings to improve food taste and flavour. Among these, the Cambodian products prahok (fish paste), kapi (shrimp paste) and toeuk trey (fish sauce) have not been examined in detail. This is the first study to investigate their chemical and microbial properties., Results: Acetic acid was the most common organic acid with the highest concentration in 10/13 samples (1.9-26.6 g kg(-1)). Lactic acid was also found at high concentrations (0.4-12.9 g kg(-1)). 16S ribosomal RNA gene-dependent phylogenetic analyses indicated that Gram-positive cocci and rods, such as Bacillus, Clostridium, Staphylococcus and Tetragenococcus, were the major microbial populations. High sodium chloride concentrations detected in these products (170-270 g kg(-1)) could be responsible for inhibition of the growth of Gram-negative putrefactive microorganisms., Conclusion: This study established a relationship between the chemical and microbial compositions of Cambodian fermented fish products, which provides a basis for preservation and maturation. These data could be beneficial in the manufacturing of these products in terms of microbial control and quality stabilisation., (© 2013 Society of Chemical Industry.)
- Published
- 2014
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27. Effective removal of cadmium from fish sauce using tannin.
- Author
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Sasaki T, Michihata T, Katsuyama Y, Take H, Nakamura S, Aburatani M, Tokuda K, Koyanagi T, Taniguchi H, and Enomoto T
- Subjects
- Animals, Fishes, Food Contamination, Food Technology instrumentation, Japan, Tannins analysis, Cadmium analysis, Fish Products analysis, Food Technology methods
- Abstract
Fish sauce prepared from squid organs contains cadmium (Cd), which may be present at hazardous concentrations. In this study, we report a new, inexpensive, and acceptable method for removing Cd from fish sauce using tannin, which is an approved food additive in Japan. Decreases in Cd concentrations of 13-fold were observed (0.39-0.03 mg/100 mL) by incorporating the soluble Cd into a precipitate generated by tannin treatment. The total nitrogen content, free amino acid content, 1,1-diphenyl-2-picrylhydrazyl radical scavenging activity, and angiotensin I-converting enzyme inhibitory activity of the treated fish sauce were the same as those of the untreated fish sauce.
- Published
- 2013
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28. Oxidized high-density lipoprotein as a risk factor for cardiovascular events in prevalent hemodialysis patients.
- Author
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Honda H, Ueda M, Kojima S, Mashiba S, Michihata T, Takahashi K, Shishido K, and Akizawa T
- Subjects
- Aged, Analysis of Variance, Biomarkers blood, Cardiovascular Diseases blood, Cardiovascular Diseases mortality, Carotid Intima-Media Thickness, Chi-Square Distribution, Female, Geriatric Assessment, Humans, Interleukin-6 blood, Japan, Kaplan-Meier Estimate, Kidney Failure, Chronic blood, Kidney Failure, Chronic complications, Kidney Failure, Chronic mortality, Male, Middle Aged, Multivariate Analysis, Nutrition Assessment, Nutritional Status, Prognosis, Proportional Hazards Models, Prospective Studies, Renal Dialysis mortality, Risk Assessment, Risk Factors, Time Factors, Up-Regulation, Cardiovascular Diseases etiology, Kidney Failure, Chronic therapy, Lipoproteins, LDL blood, Renal Dialysis adverse effects
- Abstract
Background and Objectives: Here, we assessed the impact of oxidized high-density lipoprotein (oxHDL), dysfunctional HDL, on mortality and cardiovascular disease (CVD) events in prevalent HD patients and compared oxHDL to interleukin-6 (IL-6), a strong predictor of CVD events in HD patients., Design, Setting, Participants, and Measurements: This prospective study examined a cohort of prevalent HD patients (n=412). Blood samples were obtained at baseline to measure lipids, high-sensitive C-reactive protein (hsCRP), IL-6, oxidized low-density lipoprotein, N-terminal pro B-type natriuretic peptide, intercellular adhesion molecule 1 (ICAM-1), myeloperoxidase, adiponectin, and oxHDL. Carotid intima-media thickness (CIMT) was assessed at baseline and 3-year follow-up. Nutritional status was assessed by subjective global assessment (SGA), body mass index, and geriatric nutritional risk index (GNRI). After the baseline assessment, study patients were prospectively followed up (mean observational period, 40 months)., Results: At baseline, patients with high oxHDL had a worse nutritional state and higher HDL-cholesterol (HDL-chol), ICAM-1, and adiponectin levels and a higher oxHDL/HDL-chol ratio than low oxHDL patients. A combination of high oxHDL and high IL-6 was significantly associated with increased CIMT at baseline and a larger increase in CIMT at 3-year follow-up. High oxHDL did not predict all-cause mortality; however, it was significantly associated with CVD-related mortality and composite CVD events, particularly with concomitant high IL-6. These associations were confirmed in multivariate Cox hazard models adjusted with confounding variables., Conclusions: High oxHDL, particularly with concomitant high IL-6, may be associated with an increased risk of CVD events and CVD-related mortality in prevalent HD patients., (Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.)
- Published
- 2012
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29. Olmesartan medoxomil is associated with decreased plasma AGEs, pentosidine, and N-(epsilon)-carboxymethyl-lysine levels in hemodialysis patients.
- Author
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Honda H, Hosaka N, Aoshima Y, Hirai Y, Michihata T, and Akizawa T
- Subjects
- Adult, Aged, Aged, 80 and over, Angiotensin II Type 1 Receptor Blockers therapeutic use, Arginine blood, Benzimidazoles therapeutic use, Benzoates therapeutic use, Blood Pressure drug effects, Female, Humans, Hypertension, Renal blood, Inflammation blood, Inflammation drug therapy, Kidney Failure, Chronic blood, Lysine blood, Male, Olmesartan Medoxomil, Oxidative Stress drug effects, Pilot Projects, Prospective Studies, Telmisartan, Treatment Outcome, Arginine analogs & derivatives, Glycation End Products, Advanced blood, Hypertension, Renal drug therapy, Imidazoles therapeutic use, Kidney Failure, Chronic therapy, Lysine analogs & derivatives, Renal Dialysis, Tetrazoles therapeutic use
- Abstract
Background: Advanced glycation end products (AGEs) are associated with comorbidity and death among patients on hemodialysis (HD). Angiotensin II type 1 receptor blockers (ARBs) can decrease the formation of AGEs in vitro. This study examines the ability of various ARBs to decrease plasma AGE levels in hypertensive patients on HD., Methods: This preliminary randomized prospective study included 24 hypertensive patients on HD who were treated with candesartan (8 mg/day). The patients were randomly assigned to an olmesartan (20 mg/day, n = 12) or a telmisartan (40 mg/day, n = 12) group and followed up 24 weeks. Blood pressure was monitored before each HD session, and plasma pentosidine, N-(epsilon)-carboxymethyl-lysine (CML), serum malondialdehyde-low-density lipoprotein (LDL), high-sensitive CRP, and serum total free radical (TFR) were measured at baseline, and at 4, 12, and 24 weeks., Results: Olmesartan was significantly associated with decreased systolic blood pressure compared with telmisartan. After 24 weeks of treatment, plasma pentosidine and CML levels were significantly decreased and serum TFR levels tended to be decreased in the olmesartan group, but remained unchanged in the telmisartan group., Conclusions: These results suggest that olmesartan can help to decrease plasma AGE levels in patients on HD.
- Published
- 2012
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30. Assessment of inflow of endotoxin and its fragments in patients on maintenance hemodialysis.
- Author
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Suzuki H, Honda H, Kato N, Michihata T, Takahashi K, Shishido K, and Akizawa T
- Subjects
- Adult, Aged, Aged, 80 and over, Biomarkers blood, Cross-Sectional Studies, Endotoxins metabolism, Female, Hemodialysis Solutions chemistry, Hemodialysis Solutions therapeutic use, Humans, Inflammation Mediators blood, Kidney Failure, Chronic blood, Kidney Failure, Chronic metabolism, Kidney Failure, Chronic therapy, Male, Middle Aged, Oxidative Stress, Risk Factors, Treatment Outcome, Endotoxins blood, Renal Dialysis
- Abstract
Background: We estimated the flow of endotoxins (ET) from dialysates into the blood of patients on hemodialysis (HD) using limulus amebocyte lysate (LAL) assays and endotoxin activity (EA) determined by neutrophil respiratory burst activity., Methods: A cross-sectional study compared groups given ultrapure bicarbonate (n = 15; group A), acetate-free bicarbonate dialysates (n = 20; group B) and conventional bicarbonate dialysate (n = 23; group C). A prospective study of group C examined the effect of changing the purity of the dialysate. Biomarkers of inflammation and oxidative stress were measured and ET in blood was assessed by LAL assays and EA., Results: Serum ET levels did not differ among the groups, whereas EA and the biomarkers were significantly increased in group C compared with those in groups A and B. HD using conventional dialysate was independently associated with an increase in EA. Purifying the dialysate significantly decreased EA in group C., Conclusion: Measuring EA is useful to assess the influence of dialysate contamination in HD patients., (Copyright © 2011 S. Karger AG, Basel.)
- Published
- 2011
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31. Dual-color luciferase mouse directly demonstrates coupled expression of two clock genes.
- Author
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Noguchi T, Michihata T, Nakamura W, Takumi T, Shimizu R, Yamamoto M, Ikeda M, Ohmiya Y, and Nakajima Y
- Subjects
- Animals, Crosses, Genetic, Feasibility Studies, Female, Mice, Mice, Inbred C57BL, Mice, Inbred DBA, Mice, Transgenic, NIH 3T3 Cells, RNA, Messenger genetics, RNA, Messenger metabolism, Suprachiasmatic Nucleus metabolism, Transgenes, Luciferases genetics, Luciferases metabolism
- Abstract
We have established a dual-color transgenic mouse that simultaneously reports the expression of two clock genes, Bmal1 and Per2, in a single tissue. The expression of the two genes is monitored with green- and red-emitting beetle luciferases with a single luminescent substrate. Antiphasic oscillations of Bmal1 and Per2, consistent with their endogenous mRNA profiles, were clearly monitored in the suprachiasmatic nucleus (SCN), the master circadian pacemaker, and in the peripheral tissues, demonstrating that the system allows the long-term, quantitative, and simultaneous monitoring of the expression of the two genes. We also showed that although the expression patterns of Bmal1 and Per2 in each organ are strictly antiphasic, the recorded circadian phases and periods of both genes varied between organs. The phase shifts in the expression of both genes in the SCN, induced by a change of medium, also occurred in a similar manner. Therefore, this dual-color luciferase mouse allows noninvasive and continuous monitoring of the coupled expression of two clock genes. This system provides a simple technique with which to unravel the complex interactions of two genes in the body.
- Published
- 2010
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32. Volatile compounds of headspace gas in the Japanese fish sauce ishiru.
- Author
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Michihata T, Yano T, and Enomoto T
- Subjects
- Chromatography, Gas, Gas Chromatography-Mass Spectrometry, Hydrogen-Ion Concentration, Nitrogen chemistry, Volatilization, Condiments analysis
- Abstract
Volatile compounds from the headspace gas of ten brands of the Japanese fish sauce ishiru were analyzed by GC-MS with a thermal-desorption cold-trap system. Many volatile peaks were detected and 51 compounds were identified. The major volatile compounds in ishiru included aldehydes (such as 2-methylpropanal, 2-methylbutanal, 3-methylbutanal, and benzaldehyde), nitrogen-containing compounds (such as pyrazine derivatives and trimethylamine), sulfur-containing compounds (such as dimethyl disulfide), and ketones (such as 2-butanone and 3-methyl-2-butanone). On the other hand, volatile fatty acids were nearly absent in the headspace gas of ishiru.
- Published
- 2002
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33. Surgical treatment of atherosclerotic and dysplastic aneurysms of the extracranial internal carotid artery.
- Author
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Kawada T, Oki A, Iyano K, Bitou A, Okada Y, Matsuo Y, Aiba M, Yamada M, Michihata T, Inoue K, and Takaba T
- Subjects
- Aged, Blood Vessel Prosthesis Implantation, Female, Humans, Male, Middle Aged, Polytetrafluoroethylene, Carotid Artery Diseases surgery, Carotid Artery, Internal surgery, Intracranial Aneurysm surgery
- Abstract
Atherosclerotic and dysplastic aneurysms of the extracranial internal carotid artery are rare in Japan. We have experienced only four cases since 1982. The patients were two men and two women with a mean age of 67 years (range 51 to 82 years). All four patients had a saccular type aneurysm; sizes ranged from 30 to 75 mm. Aneurysmectomy and end-to-end anastomosis of the internal carotid artery could be performed in two patients. One patient underwent aneurysmorrhaphy followed by primary closure of the internal carotid artery, and the remaining patient underwent aneurysmectomy followed by a prosthetic graft replacement (6 mm-PTFE graft). During aneurysm repair, simple arterial cross-clamping (time 18 to 57 min; mean +/- SD: 31.3 +/- 18.0 min) was used in all patients. During arterial clamping of the carotid artery in two patients, somatosensory evoked potentials and regional cerebral oxygen saturation detected by near-infrared spectroscopy remained within normal ranges. All patients survived without neurologic deficits. These findings indicate that intraluminal shunting may be unnecessary during aneurysm repair if the patient does not have obstructive disease in the contralateral carotid artery and if no somatosensory evoked potentials or regional cerebral oxygen saturation abnormalities occur during proximal arterial clamping. After aneurysmectomy, end-to-end anastomosis of the internal carotid artery is the preferred method of repair if the length of the distal internal carotid artery permits.
- Published
- 2002
34. Hyperacute xenorejection of guinea pig-to-rat lung transplantation can be attenuated by blood which has perfused another xenograft.
- Author
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Nonaka M, Kadokura M, Kataoka D, Michihata T, Inoue K, Kawada T, and Takaba T
- Subjects
- Acute Disease, Animals, Blood Cell Count, Complement Hemolytic Activity Assay, Complement System Proteins metabolism, Graft Rejection blood, Graft Rejection etiology, Hematocrit, Hemoglobins metabolism, Pulmonary Edema blood, Pulmonary Edema etiology, Pulmonary Edema prevention & control, Rats, Rats, Sprague-Dawley, Swine, Transplantation, Heterologous, Blood Transfusion methods, Graft Rejection prevention & control, Lung Transplantation adverse effects, Perfusion
- Abstract
In discordant xenotransplantation, the recipientOs blood initiates hyperacute xenorejection (HXR). We hypothesized that HXR-related lung edema may be reduced if a new xenograft is perfused by blood which previously has perfused another xenograft. In a syngeneic control group (n = 6), a rat lung (lung XR) was perfused by rat blood (blood AR), following which the blood was collected (blood BR). After another rat lung (lung YR) was perfused by blood BR, the blood was collected (blood CR). In a xenogeneic experimental group (n = 6), a guinea pig lung (lung XG) was perfused by rat blood (blood AG), and the blood was collected (blood BG). Then, another guinea pig lung (lung YG) was perfused by blood BG, and once more the blood was collected (blood CG). White blood cells (WBC), polymorphonuclear leukocytes (PMN), red blood cells (RBC), hemoglobin, hematocrit, and complement (CH50) in the blood were measured pre- and post-perfusion. The wet/dry weight ratio (W/D) of the lung was calculated after the perfusion. WBC and PMN were higher in blood CR/BR than in blood BR/AR. CH50 was higher in blood CG/BG than in blood BG/AG. RBC, hemoglobin, and hematocrit were not different among the blood AR, BR, CR, AG, BG, and CG. The W/D was not different between lung XR and lung YR. The W/D of lung YG was lower than lung XG. In conclusion, the lung edema associated with HXR is reduced when blood which has perfused another xenograft is used to perfuse the new xenograft without anemia, and complement plays a critical role in reducing lung edema.
- Published
- 2000
35. Exercise-induced QTc-interval changes for predicting improvement in regional blood flow in ischemic myocardium and cardiac output after coronary angioplasty in patients with right bundle-branch block.
- Author
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Watanabe T, Michihata T, Yamanaka H, Akutsu Y, Okazaki O, Katagiri T, and Harumi K
- Subjects
- Adult, Aged, Analysis of Variance, Cardiac Output physiology, Coronary Angiography, Exercise Test, Female, Humans, Male, Middle Aged, Myocardial Ischemia diagnosis, Predictive Value of Tests, Prognosis, Regional Blood Flow, Statistics, Nonparametric, Tomography, Emission-Computed, Angioplasty, Balloon, Coronary, Bundle-Branch Block diagnosis, Coronary Circulation physiology, Electrocardiography, Myocardial Ischemia diagnostic imaging, Myocardial Ischemia therapy
- Abstract
Background: We have previously shown that QT-interval changes are more useful than ST-T changes in evaluating the severity of exercise-induced myocardial ischemia in patients with right bundle-branch block (RBBB)., Hypothesis: The purpose of this study was to evaluate whether the improvement in regional myocardial blood flow (RMBF) in ischemic areas and cardiac output after percutaneous transluminal coronary angioplasty (PTCA) can be predicted by exercise-induced QT-interval changes prior to PTCA., Methods: The RMBF and cardiac output were quantified with nitrogen-13 ammonia positron emission tomography at rest and during exercise in 20 patients with RBBB and ischemic heart disease before and 6 months after PTCA, and in 9 healthy volunteers., Results: Before PTCA, exercise-induced prolongation by < 20 ms or shortening of the Bazett-corrected QT (QTc) interval (454 +/- 38 to 451 +/- 41 ms, p = NS) was observed in 13 patients (Group 1) and prolongation by > or = 20 ms (429 +/- 44 to 466 +/- 50 ms, p < 0.002) was observed in 7 (Group 2). The number of regions of exercise-induced ischemia was significantly greater in Group 2 than in Group 1 (4.0 +/- 1.2 vs. 2.1 +/- 1.2, p < 0.01). The RMBF in regions of exercise-induced ischemia and cardiac output at rest was not significantly different between Groups 1 and 2, whereas during exercise both the parameters were significantly lower in Group 2 than in Group 1 (both p < 0.05). After successful PTCA, RMBF both at rest and during exercise improved significantly in Group 1 (0.67 +/- 0.04 to 0.71 +/- 0.06 ml/min/g, 0.74 +/- 0.05 to 0.84 +/- 0.08 ml/min/g; both p < 0.0001), but did not improve significantly in Group 2 (0.63 +/- 0.05 to 0.65 +/- 0.07 ml/min/g, 0.65 +/- 0.04 to 0.69 +/- 0.11 ml/ min/g; both p = NS). Cardiac output during exercise improved significantly in Group 1 (6.4 +/- 0.7 to 7.4 +/- 0.9 l/min; p < 0.002) but not in Group 2 (5.7 +/- 0.6 to 5.9 +/- 0.6 l/min; p = NS)., Conclusions: Our results suggest that the marked prolongation of the QTc interval induced by pre-PTCA exercise may predict a lack of improvement in RMBF in ischemic areas and cardiac output after PTCA in patients with RBBB and ischemic heart disease.
- Published
- 2000
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36. Exercise-induced ST-segment depression: imbalance between myocardial oxygen demand and myocardial blood flow.
- Author
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Watanabe T, Akutsu Y, Yamanaka H, Michihata T, Okazaki O, Katagiri T, and Harumi K
- Subjects
- Adult, Aged, Angina Pectoris diagnosis, Angina Pectoris physiopathology, Coronary Angiography methods, Coronary Angiography statistics & numerical data, Coronary Disease diagnosis, Coronary Disease physiopathology, Exercise Test methods, Exercise Test statistics & numerical data, Female, Humans, Male, Middle Aged, Myocardial Ischemia diagnosis, Myocardial Ischemia physiopathology, Reference Values, Tomography, Emission-Computed methods, Tomography, Emission-Computed statistics & numerical data, Coronary Circulation physiology, Electrocardiography, Exercise physiology, Myocardium metabolism, Oxygen Consumption physiology
- Abstract
Objective: ST-segment depression is believed as a common electrocardiographic sign of myocardial ischemia during exercise testing. Ischemia is generally defined as oxygen deprivation due to reduced perfusion. However, the exact relationship of the ischemic definition to ST-segment depression remains unclear. This study was conducted to evaluate the correlation between myocardial oxygen demand and myocardial blood flow (MBF) when ischemic (horizontal or downsloping) ST-segment depression of > or = 0.1 mV 80 ms after the J point developed during low-level exercise., Methods and Results: Seventy-two patients with angiographically proven coronary artery disease (CAD) and 9 healthy volunteers underwent exercise positron emission tomography (PET). Myocardial oxygen demand was defined as a rate-pressure product (RPP, heart rate x systolic blood pressure) during exercise and MBF was quantified by nitrogen-13 ammonia perfusion PET. The myocardial demand-supply balance (MDSB) index was calculated from the MBF ratio (values during exercise/values at rest) against the RPP ratio (values during exercise/values at rest). The MDSB index was significantly lower in patients with ischemic ST-segment depression than in patients with non-ischemic ST depression and healthy volunteers (0.82 +/- 0.16 vs. 1.02 +/- 0.17, p < 0.0001 and vs. 0.99 +/- 0.14, p = 0.0109). Further, the presence of inadequate increase in MBF of < or = 10% (2 SD below the mean % value of healthy volunteers) during exercise in regional myocardium perfused by stenotic CAD significantly correlated with exercise-induced ischemic ST-segment depression (p = 0.0105)., Conclusions: Our study could demonstrate that exercise-induced ischemic ST-segment depression is associated with myocardial ischemia due to exercise-induced imbalance between myocardial oxygen demand and global and regional MBF supply in patients with proven CAD.
- Published
- 2000
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37. Brady-tachycardia syndrome after radiotherapy for lung cancer. Assessment by computed tomography and carbon-11 methionine positron emission tomography.
- Author
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Watanabe T, Okazaki O, Izumo K, Michihata T, Katagiri T, and Harumi K
- Subjects
- Aged, Bradycardia etiology, Carbon Radioisotopes, Humans, Male, Methionine, Sinoatrial Node radiation effects, Tachycardia etiology, Bradycardia diagnosis, Carcinoma, Squamous Cell radiotherapy, Lung Neoplasms radiotherapy, Radiotherapy adverse effects, Tachycardia diagnosis, Tomography, Emission-Computed, Tomography, X-Ray Computed
- Abstract
A 74-year-old male who had received radiotherapy (total 54 Gy) for right lung cancer 7 months earlier developed a symptomatic brady-tachycardia syndrome requiring the implantation of a permanent pacemaker. Chest CT showed a pulmonary tumor of 2-cm diameter in the right lower lobe with direct extension into the surrounding tissue, suggesting the possibility of cardiac invasion. Carbon-11 methionine positron emission tomography (PET) indicated the absence of visible invasion of the heart with lung cancer. The bradytachycardia syndrome, therefore, was considered to be associated with sinus node injury due to radiation. Carbon-11 methionine PET metabolic imaging might play an important role in evaluating noninvasively the cause of the arrhythmia in this patient.
- Published
- 1999
- Full Text
- View/download PDF
38. [Risk assessment in urgent or emergent coronary artery bypass grafting for acute coronary syndrome].
- Author
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Michihata T, Oki A, Iyano K, Asano M, Ozawa A, Narisawa T, Aiba M, Murata N, Yamada M, Kawada T, and Takaba T
- Subjects
- Adult, Aged, Aged, 80 and over, Angina, Unstable surgery, Emergency Treatment, Female, Humans, Male, Middle Aged, Myocardial Infarction surgery, Prognosis, Risk Factors, Coronary Artery Bypass
- Abstract
Emergent coronary artery bypass grafting (CABG) for the treatment of acute coronary syndrome has increased the operative mortality. Forty-nine patients underwent urgent or emergent CABG for the treatment of medically refractory unstable angina in 10 patients, and for acute myocardial infarction (AMI) in 39 patients. Ten operative deaths were occurred in the AMI patients, and the mortality was 20 percent. The preoperative risk factors were evaluated in 10 patients who died in the operative period. Cardiopulmonary resuscitation before operation, intra aortic balloon pumping, the use of catecholamine, and intubation with or without percutaneous cardiopulmonary support revealed operative risk factor. Because the patients who have preoperatively shock, it seemed to be needed that the rescue of the patients should improve the clinical results for urgent or emergent CABG.
- Published
- 1999
39. How different surgical methods of performing right upper lobectomy contribute to postoperative bronchial branching deformity: an experimental study.
- Author
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Nonaka M, Kadokura M, Michihata T, Inoue K, and Takaba T
- Subjects
- Animals, Lung pathology, Postoperative Complications prevention & control, Rabbits, Trachea pathology, Trachea surgery, Pneumonectomy methods, Surgical Stapling methods
- Abstract
It has been suggested that postoperative bronchial deformity is a complication of surgery and that the surgical methods employed may play a role in its development. We studied the relationship between postoperative bronchial branching deformity and various surgical methods, including hand suturing or mechanical stapling of right upper (RU) lobectomy, versus wedge or sleeve bronchoplasty with RU lobectomy. We used an in situ bronchial casting model in rabbits and measured the branching angles between: the trachea and the right main bronchus (RMB); the trachea and the left main bronchus; the RMB and the intermediate bronchus (IB); the IB and the right middle lobe bronchus (RMLB); and the RMLB and the coronal plane. In the mechanical stapling group, the angle between the RMB and the IB was wider than in the hand suturing group, and the RMLB diverged more laterally. In the wedge plasty group, the angle between the trachea and the RMB was wider, while that between the IB and the RMLB was narrower than in the hand suturing group. In the sleeve plasty group, the angle between the RMB and the IB and that between the IB and the RMLB were wider than in the hand suturing group. The findings of this experiment clearly demonstrate that postoperative deformity of the distal bronchus varies according to the surgical methods used.
- Published
- 1999
- Full Text
- View/download PDF
40. Correlation between exercise-induced ischemic ST-segment depression and myocardial blood flow quantified by positron emission tomography.
- Author
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Watanabe T, Harumi K, Akutsu Y, Yamanaka H, Michihata T, Okazaki O, and Katagiri T
- Subjects
- Adult, Aged, Animals, Confounding Factors, Epidemiologic, Coronary Angiography, Electrocardiography, Exercise Test methods, Female, Humans, Male, Middle Aged, Bicycling, Coronary Circulation, Heart Conduction System, Myocardial Ischemia diagnostic imaging, Myocardial Ischemia physiopathology, Tomography, Emission-Computed methods
- Abstract
Background: Ischemic ST-segment depression (horizontal or downsloping) is the most common manifestation of exercise-induced myocardial ischemia. The mechanisms responsible for these types of ST-segment depression are largely unknown. We investigated the relation of these 2 types of exercise-induced ST-segment depression to changes in regional myocardial blood flow (RMBF) by using exercise positron emission tomography (PET)., Methods and Results: The RMBF was measured with nitrogen-13 ammonia PET both at rest and during low-level supine bicycle exercise in 27 patients with angiographically proven coronary artery disease and in 6 healthy volunteers. ST-segment depression was measured from the isoelectric PR segment 80 ms after the J point. Exercise-induced horizontal ST-segment depression > or =0.1 mV was observed in 9 patients and downsloping depression > or =0.1 mV was observed in 18 patients. Multivessel disease was more frequent and areas of exercise-induced ischemia were larger in patients with downsloping depression than in patients with horizontal depression (P < .02, P < .05). In patients with horizontal ST-segment depression, RMBF in ischemic areas and in surrounding areas increased by a similar amount (31%+/-29% and 32%+/-16%) with exercise. In patients with downsloping ST-segment depression, RMBF was unchanged or decreased in ischemic areas (10%+/-24%) but increased in surrounding areas (46%+/-27%) with exercise. In healthy volunteers, RMBF increased in all areas (56%+/-30%) with exercise., Conclusions: Compared with horizontal changes in ST-segment morphology, downsloping changes may better indicate severe ischemia and greater differences in the increase of blood flow with exercise in the ischemic myocardium and in the surrounding areas.
- Published
- 1998
- Full Text
- View/download PDF
41. Correlation between myocardial blood flow and fasting glucose metabolism in ischemic heart disease. Quantitative assessment by nitrogen-13 ammonia and fluorine-18 fluorodeoxyglucose positron emission tomography.
- Author
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Watanabe T, Okazaki O, Akutsu Y, Yamanaka H, Michihata T, Katagiri T, and Harumi K
- Subjects
- Aged, Coronary Angiography, Electrocardiography, Female, Humans, Male, Middle Aged, Myocardial Ischemia diagnostic imaging, Myocardial Ischemia metabolism, Ammonia, Coronary Circulation, Fasting metabolism, Fluorodeoxyglucose F18, Glucose metabolism, Heart diagnostic imaging, Myocardial Ischemia physiopathology, Myocardium metabolism, Nitrogen Radioisotopes, Radiopharmaceuticals, Tomography, Emission-Computed methods
- Abstract
Ischemic myocardium avidly incorporates fluorine-18 fluorodeoxyglucose (F-18 FDG) in the fasting state, in contrast to the relative absence of F-18 FDG uptake in normal myocardium with sufficient blood flow in the fasting state. Although many studies have attempted to use F-18 FDG uptake to discriminate ischemic but viable myocardium from scarred myocardium, little is known clinically about the correlation between blood flow and F-18 FDG uptake in ischemic myocardium. We studied the critical level of blood flow that causes avid F-18 FDG uptake in myocardium in 9 patients. All patients had angiographically proven ischemic heart disease but no diabetes. Regional myocardial blood flow (RMBF) was measured quantitatively by positron emission tomography (PET) using nitrogen-13 ammonia in the resting state, in which the normal value was 80.2 +/- 13.0 ml/min/100 cm3. The F-18 FDG uptake in myocardium was assessed with the differential uptake ratio (DUR) scale. We constructed circumferential profiles of radioactivity uptake in myocardium for each study, and chose 780 sections of myocardium in which the relation between the two factors could be analyzed. In moderately ischemic to normal myocardium with RMBF of 50 to 90 ml/min/100 cm3, RMBF and F-18 FDG uptake were negatively correlated (r = -0.44, p < 0.01). When RMBF was 50 to 60 ml/min/100 cm3 (n = 121), the peak DUR value of F-18 FDG uptake was 4.0 +/- 2.0. The two factors were not correlated when RMBF was less than 50 ml/min/100 cm3 or 90 ml/min/100 cm3 or higher. Our results suggest that RMBF and F-18 FDG uptake values as measured with PET may provide valuable information on the possible benefit of intervention in ischemic heart disease.
- Published
- 1998
- Full Text
- View/download PDF
42. Correlations between resting regional wall motion and regional myocardial blood flow (at rest and during exercise) in infarct-related myocardium--a study with [13N]ammonia positron emission tomography.
- Author
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Akutsu Y, Harumi K, Michihata T, Watanabe T, Yamanaka H, Okazaki O, Kashida M, Hasegawa M, and Katagiri T
- Subjects
- Adult, Aged, Ammonia, Animals, Exercise Test, Female, Gated Blood-Pool Imaging, Heart Ventricles diagnostic imaging, Humans, Male, Middle Aged, Myocardial Infarction diagnostic imaging, Nitrogen Radioisotopes, Tomography, Emission-Computed methods, Coronary Circulation physiology, Heart Ventricles physiopathology, Myocardial Infarction physiopathology, Rest physiology
- Abstract
We evaluated quantitatively the correlations between resting wall motion and regional myocardial blood flow (RMBF; at rest and during exercise) in infarct-related myocardium. The study was performed in 28 subjects: 21 patients who had previously suffered myocardial infarction of the anteroseptal wall, and 7 normal individuals. Positron emission tomography (PET) with [13N]ammonia was performed at rest and during low-grade exercise (bicycle ergometer fixed at 25 W for 6.5 min), and RMBF was measured quantitatively from the radioactivity in myocardial tissue and arterial blood. Resting regional wall motion was calculated using the centerline method on left ventriculographic findings. Resting regional wall motion was correlated with RMBF both at rest and during exercise in the infarct areas (anterior walls; y = 2.74 +/- 4.25 x 10(-2)x, r = 0.43, at rest; and y = -2.48 + 3.04 x 10(-2)x, r = 0.48, during exercise, p < 0.05; septal walls; y = -3.61 + 5.64 x 10(-2)x, r = 0.62, at rest; and y = -3.46 + 4.31 x 10(-2)x, r = 0.62, during exercise, p < 0.01). In each infarct-related wall, the coefficient (the slope) during exercise was smaller than that at rest (3.04 vs 4.25 and 4.31 vs 5.64 in each), and the infarct areas with preserved wall motion showed higher RMBF during exercise than those with reduced wall motion. Our results may show that wall motion depends on viable but ischemic myocardium in infarct-related walls.
- Published
- 1997
- Full Text
- View/download PDF
43. [A case of aneurysm of the descending thoracic aorta associated with Behçet's disease].
- Author
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Hirata I, Kimura S, Michihata T, Osawa H, Kume M, and Kashima T
- Subjects
- Aged, Aorta, Thoracic surgery, Aortic Aneurysm, Thoracic etiology, Aortic Rupture etiology, Blood Vessel Prosthesis Implantation, Humans, Male, Aortic Aneurysm, Thoracic surgery, Aortic Rupture surgery, Behcet Syndrome complications
- Abstract
A 66-year-old male with Behçet's disease admitted again with hemoptysis. He underwent the resection and direct closure of descending aortic aneurysm 3 years ago, followed without the use of steroid. Chest CT scanning demonstrated a recurrent aneurysm of the descending aorta which was could not be detected on the previous CT only 23 days before. In the current operation, we performed resection, direct closure and wrapping of the aneurysm. The pathological examination showed a true aneurysm of Behçet's disease. The patient is free from recurrence for 17 months since the operation under steroid therapy.
- Published
- 1997
44. Significance of downsloping ST-segment depression induced by low-level exercise in severe coronary artery disease. Assessment with myocardial ischemia and collateral perfusion.
- Author
-
Watanabe T, Harumi K, Akutsu Y, Yamanaka H, Okazaki O, Michihata T, and Katagiri T
- Subjects
- Adult, Aged, Ammonia, Collateral Circulation, Female, Humans, Male, Middle Aged, Nitrogen Radioisotopes, Tomography, Emission-Computed, Coronary Circulation, Coronary Disease physiopathology, Electrocardiography, Exercise Test, Heart diagnostic imaging, Myocardial Ischemia physiopathology, Perfusion methods
- Abstract
Exercise-induced downsloping ST-segment depression is a common manifestation of severe myocardial ischemia. Although greater downsloping ST-segment depression is suspected to indicate more severe ischemia, its exact relationship to regional myocardial blood flow (RMBF) has not yet been clarified. We investigated the relationship between the magnitude of downsloping ST-segment depression and exercise-induced changes in RMBF and collateral perfusion. Nitrogen-13 ammonia positron emission tomography was performed in 6 healthy volunteers and 72 patients with angiographically proven coronary artery disease. The left ventricle was divided into 11 regions of interest, and RMBF in each region was measured at rest and during low-level supine bicycle exercise. Downsloping ST-segment depression of 0.1 mV or more at 80 milliseconds after the J point was accepted as significant. Low-level exercise induced downsloping depression of 0.1 to 0.2 mV in 10 patients (group D1) and downsloping depression of 0.2 mV or more in 8 patients (group D2). Multivessel disease was common in both group D1 (80% of patients) and group D2 (88% of patients). Collateral circulation was significantly more frequent in group D1 (90%) than in group D2 (13%, p < 0.01). Ischemic areas were larger and cardiac function was worse in group D2 than in group D1. The RMBF increased sufficiently in all regions (56 +/- 30%) with exercise in the healthy group. In group D1, RMBF was unchanged or decreased in ischemic areas (10 +/- 23%) but increased sufficiently in surrounding areas (50 +/- 32%). In group D2, RMBF was unchanged in ischemic areas (17 +/- 24%) and increased insufficiently in surrounding areas (41 +/- 21%). Therefore, exercise-induced downsloping ST-segment depression of 0.1 to 0.2 mV may reflect an underlying change in blood flow in viable myocardium with collateral perfusion, and downsloping depression of 0.2 mV or more may reflect more severely impaired myocardium without collateral perfusion.
- Published
- 1997
- Full Text
- View/download PDF
45. [Efficacy of coronary artery reconstruction in maintaining myocardial viability: quantitative determination of local myocardial circulation with 13NH3 myocardial positron emission tomography].
- Author
-
Kobayashi S, Takaba T, Kume M, Kashima T, and Michihata T
- Subjects
- Adult, Aged, Female, Humans, Male, Middle Aged, Myocardial Infarction pathology, Myocardial Infarction physiopathology, Myocardial Infarction surgery, Postoperative Period, Saphenous Vein transplantation, Thoracic Arteries transplantation, Tissue Survival, Tomography, Emission-Computed, Vascular Patency, Coronary Artery Bypass, Coronary Circulation, Heart diagnostic imaging, Myocardium pathology
- Abstract
Thirty patients (280 areas) whose bypass grafts remained patent after surgical reconstruction of the coronary artery were examined. Before and after reconstruction, local myocardial blood circulation in infarcted regions and post-stenotic regions was measured by 13 NH(3) myocardial positron emission computed tomography (PET) at rest of during physical exercise in order to evaluate the efficacy of coronary artery reconstruction. Before operation, mean blood flow in post-stenotic regions (n = 198) was 65 +/- 15 ml/min/100 g at rest and 85 +/- 23 ml/min/100 g during exercise. After coronary artery bypass grafting (CABG), mean blood flow was increased to 78 +/ 21 ml/min/100 g at rest (p, 0.01) and 105 +/- 32 ml/min/100 g during exercise (p < 0.01). In infarcted regions (n = 82), mean blood flow before operation was 51 +/- 23 ml/min/100 g at rest and 69 +/- 23 ml/min/100 g during exercise. After CABG, it increased to 62 +/- 19 ml/min/100 g at rest (p < 0.01) and 81 +/- 29 ml/min/100 g during exercise (p < 0.01). Thus, significant increases in blood flow were observed in both post-stenotic and infarcted regions at rest and physical exercise after operation. The regions of infarction were divided into three groups based on local myocardial blood flow at rest before operation: Group I: greater than 45 ml/min/100 g (n = 35); Group II: less than 45 ml/min/100 g (n = 30) but greater than 30 ml/min/100 g; and Group III: less than 30 ml/min/100 g (n = 30). The efficacy of reconstruction was compared among these groups. The group with preoperative myocardial blood flow greater than 30 ml/min/100 g had increased blood flow after operation, indicating myocardial viability.
- Published
- 1996
46. [A case of surgically treated hypertrophic obstructive cardiomyopathy suffering from angina pectoris during hemodialysis].
- Author
-
Yamada M, Ozawa A, Sekiguchi S, Matsuo Y, Takaba T, Ozawa M, and Michihata T
- Subjects
- Cardiomyopathy, Hypertrophic etiology, Humans, Male, Middle Aged, Angina Pectoris complications, Cardiomyopathy, Hypertrophic surgery, Renal Dialysis
- Abstract
Surgical procedure for hypertrophic obstructive cardiomyopathy (HOCM) in a patient chronic hemodialysis has not been reported in Japan. This is a case report of a 61-year-old male who had been suffering from angina pectoris during hemodialysis. Cardiac catheterization showed a systolic pressure gradient of 79 mmHg at the left ventricular outflow tract and left ventriculogram demonstrated severe mitral regurgitation. He underwent mitral valve replacement and left ventricular myectomy with hemodialysis and extracorporeal ultrafiltration method during cardiopulmonary bypass. Postoperative catheterization showed a decrease of pressure gradient to 19 mmHg at the left ventricular outflow tract, and relief of angina was obtained.
- Published
- 1996
47. Relation between cardiac index and regional myocardial blood flow in the non-infarcted wall using PET with 13NH3 in healed myocardial infarction.
- Author
-
Yamanaka H, Akutsu Y, Watanabe T, Okazaki O, Michihata T, Hasegawa M, Hara T, Katagiri T, and Harumi K
- Subjects
- Aged, Ammonia, Female, Humans, Male, Middle Aged, Myocardial Contraction, Myocardial Infarction diagnostic imaging, Myocardial Infarction pathology, Myocardium pathology, Nitrogen Radioisotopes, Tomography, Emission-Computed, Cardiac Output, Coronary Circulation, Heart diagnostic imaging, Myocardial Infarction physiopathology
- Abstract
It is not clear whether there is any relationship between cardiac output and myocardial blood flow in the infarcted heart. We measured regional myocardial blood flow (RMBF) quantitatively by positron emission tomography (PET) with 13N-ammonia at rest in 18 patients with prior myocardial infarction. RMBF was calculated using the radioactivity in myocardial tissue measured by PET and the radioactivity of arterial blood. Cardiac output was determined by the dilution method using 13NH3 as an indicator, and the relation between cardiac output and RMBF was evaluated at the same time during PET study. There was a good linear correlation between cardiac index (C.I.) and mean RMBF in non-infarcted myocardium (r = 0.45, p < 0.05), and non-infarcted size (r = 0.74, p < 0.01). There was an even better linear correlation between C.I. and sigma RMBF (representing the product of mean RMBF and non-infarcted size) as follows: y = 0.016x + 1.94, r = 0.76 (p < 0.001). It was indicated that the value of C.I. may be related to RMBF of non-infarcted myocardium and its size.
- Published
- 1995
- Full Text
- View/download PDF
48. Determination of regional myocardial blood flow with 13N-ammonia positron emission tomography during low-grade exercise for evaluating coronary artery stenosis.
- Author
-
Akutsu Y, Hara T, Watanabe T, Yamanaka H, Okazaki O, Kashida M, Michihata T, Hasegawa M, Harumi K, and Katagiri T
- Subjects
- Adult, Ammonia, Constriction, Pathologic diagnostic imaging, Coronary Disease pathology, Coronary Disease physiopathology, Exercise Test, Female, Humans, Male, Middle Aged, Nitrogen Radioisotopes, Coronary Circulation, Coronary Disease diagnostic imaging, Heart diagnostic imaging, Tomography, Emission-Computed
- Abstract
We measured regional myocardial blood flow (RMBF) by positron emission tomography (PET) with 13N-ammonia at rest and during low-grade exercise using a bicycle ergometer fixed at 25 watts for 6.5 min. The ischemic area with severe coronary artery stenosis was evaluated in terms of quantitative RMBF. The study was performed in 46 subjects consisting of 19 patients with old myocardial infarction, 20 with effort angina pectoris, and 7 normal individuals. RMBF was calculated using the radioactivity in myocardial tissue measured by PET and the radioactivity in arterial blood. The PET data were compared with coronary arteriographic findings and ECG findings. When the analysis was restricted to the anterior wall of the myocardium, it was found that exercise caused RMBF to increase by 44.9% (n = 28) in normal area, to increase by 23.3% (n = 37) in severely stenotic area (stenosis > or = 90%), and to decrease by 17.4% (n = 20) in infarcted area. When we considered only the infarcted area of the entire heart, exercise caused RMBF to decrease by 26.6% (n = 30) in the area of angiographically positive collaterals, and to increase by 0.8% (n = 31) in the area of negative collaterals. Thus, we were able to quantitate the degree of ischemia in myocardium that was associated with severe coronary artery stenosis. By application of low-grade exercise, RMBF in normal myocardium increased, while RMBF in myocardium perfused by collaterals decreased.
- Published
- 1994
- Full Text
- View/download PDF
49. Long-term effects of mass screening for neuroblastoma in infancy.
- Author
-
Sawada T, Matsumura T, Kawakatsu H, Sugimoto T, Kuroda H, Hosoi H, Michihata T, Saida T, and Hino T
- Subjects
- Adrenal Gland Neoplasms epidemiology, Age Factors, Child, Preschool, Humans, Infant, Longitudinal Studies, Mediastinal Neoplasms epidemiology, Neoplasm Staging, Neuroblastoma epidemiology, Neuroblastoma mortality, Retroperitoneal Neoplasms epidemiology, Survival Rate, Mass Screening, Neuroblastoma diagnosis
- Abstract
Eighty-four neuroblastoma patients were treated at the Department of Pediatrics, Kyoto Prefectural University of Medicine, during the 27 years from 1962 to 1988. They were divided into three groups: 35 cases in phase 1, the 12 years before mass screening from 1962 to 1974; 22 in phase 2, the 8 years after the onset of mass screening by a qualitative vanillylmandelic acid (VMA) test from 1974 to 1982; and 27 in phase 3, the recent 6 years from 1983 to 1988, after the introduction of mass screening by quantitative assay for VMA and homovanillic acid using high performance liquid chromatography. The clinical findings of these patients were compared for each phase. In Kyoto, the number of annual neuroblastoma cases diagnosed under 1 year of age increased from 0.58 in phase 1 to 1.50 in phase 2 and 3.17 in phase 3. The number of cases over 2 years of age decreased from 2.00 in phase 1 to 0.88 in phase 2 and 1.00 in phase 3. Survival rates increased from 17.1% (six of 35) in phase 1 to 54.5% (12 of 22) in phase 2 and 85.2% (23 of 27) in phase 3. The annual number of neuroblastoma deaths decreased from 2.42 in phase 1 to 1.25 in phase 2 and 0.67 in phase 3. Mass screening for neuroblastoma in infancy has increased the long-term survival rates of neuroblastoma cases treated at this hospital.
- Published
- 1991
- Full Text
- View/download PDF
50. Quantitative measurement of regional myocardial blood flow in patients with coronary artery stenosis by intravenous injection of 13N-ammonia and positron emission tomography.
- Author
-
Hara T, Michihata T, Okazaki O, Kashima T, Morimoto K, Masuoka T, Iio M, Harumi K, and Yokoi F
- Subjects
- Constriction, Pathologic, Coronary Disease physiopathology, Humans, Nitrogen Radioisotopes, Ammonia, Coronary Circulation, Coronary Disease diagnostic imaging, Tomography, Emission-Computed
- Published
- 1991
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