74 results on '"H. Okumura"'
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2. List of contributors
- Author
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R. Accomo, N. Achtziger, S.J.A. Adams, I. Akasaki, J.P. Albert, H. Amano, R. André, A. Antonelli, M. Asif Khan, R.L. Aulombard, R.F. Austin, G. Balestrino, R. Baltramiejūnas, F. Bechstedt, N. Bécourt, L. Bergman, J. Bernholc, D. Bertho, CM. Bertoni, S. Billat, M. Boćkowski, C. Bodin, C. Bodin-Deshayes, E.B. Boiko, P. Boring, A. Bouhelal, G. Bratina, K.F. Brennan, P.R. Briddon, O. Briot, I. Broser, A. Bsiesy, E. Bucher, A. Burchard, G. Cantwell, C.H. Carter, T. Castro, B.C. Cavenett, D.J. Chadi, K.M. Chen, X. Chen, H. Cheng, W.J. Choyke, N.E. Christensen, J. Cibert, R. Cingolani, T. Cloitre, P.I. Cohen, A.T. Collins, H.L. Cotal, A. Cricenti, M. Dabbicco, L.S. Dang, R.F. Davis, M. Deicher, J.M. DePuydt, B. Dischler, V.A. Dmitriev, J.F. Donegan, J.P. Doran, J.J. Dubowski, L. Eckey, J.A. Edmond, A.L. Efros, R.J. Egan, F. Engelbrecht, W. Evstropov, M. Fanciulli, R.D. Feldman, A.C. Felici, M. Ferrara, L. Ferrari, D.K. Ferry, G. Feuillet, M. Fiedler, F. Finocchi, R. Fischer, G. Fishman, A. Franciosi, Ch. Fricke, S.I. Frolov, D. Fuchs, G. Galli, S.V. Gaponenko, F. Gaspard, V.I. Gavrilenko, V. Gavryushin, W. Gebhardt, I.N. Germanenko, J. Geurts, K.P. Geyzers, B. Gil, W. Gladfelter, G. Gleitsman, E.O. Göbel, C. Godet, O. Goede, I. Gorczyca, V.P. Gribkovskii, I. Grzegory, H.-E. Gumlich, R.L. Gunshor, A.L. Gurskii, J. Gutowski, F. Gygi, M.A. Haase, C Haberstroh, W.C. Harsch, I. Hauksson, S. Hayashi, J. Hegarty, W. Heimbrodt, K. Heime, V. Heine, R. Heitz, R. Helbig, B. Henderson, F. Henneberger, R. Hérino, J. Hermans, M. Heuken, A. Hoffmann, H. Hoffmann, N. Hoffmann, H. Hofsäss, T.P. Humphreys, R.W. Hunt, S. Iarlori, S. Iida, K. Ikoma, J.P. Itie, K. Jacobs, S.G. Jahn, J.M. Jancu, C. Jaussaud, T. Jentzsch, R.L. Johnson, R. Jones, C. Jouanin, P.H. Jouneau, J. Jun, V. Jungnickel, D. Juodžbalis, S.A. Kajihara, J. Kanicki, S. Karmann, H. Katayama-Yoshida, Y. Kawakami, A. Kazlauskas, A. Kean, M.R.H. Khan, R.D. King-Smith, H. Kinto, U. Kißmann, A. Klimakow, N.I. Klyui, N. Koide, P. Koidl, H.-S. Kong, H.S. Kong, Th. König, J. Kono, V.K. Kononenko, M. Kotaki, C. Kreß, T. Krings, St. Krukowski, V. Kubertavicius, G.H. Kudlek, W. Kuhn, K. Kunc, Y. Kuroda, J.N. Kuznia, K.W. Kwak, G. Labrunie, D.B. Laks, W.R.L. Lambrecht, S. Lankes, V. Yu. Lebed, T. Lei, S. Leibenzeder, M. Lepore, T. Licht, M. Ligeon, I. Yu. Linkov, E. Litwin-Staszewska, S. Logothetidis, G. Luce, E.V. Lutsenko, M. Ch. Lux-Steiner, F. Madéore, R. Magerle, H.-E. Mahnke, K. Maier, I.E. Malinovskii, K. Manabe, M. Marinelli, B.G. Markey, A. Markwitz, T. Marshall, H. Mathieu, H. Matsunami, J.O. McCaldin, T.C. McGill, S.W.S. McKeever, J. Meier, I. Mihalcescu, E. Milani, A.I. Mitcovets, T. Mitsuyu, N. Miura, R.J. Molnar, E. Molva, M. Morohashi, Ya.V. Morozenko, T.D. Moustakas, A. Mujica, G. Mula, F. Muller, W. Müller-Sebert, A. Muñoz, A. Mura, A. Naumov, R.J. Needs, R.J. Nemanich, R. Nicolini, A.V Nurmikko, K.P. O'Donnell, T. Oguchi, K. Ohkawa, S. Okamoto, N. Okazaki, H. Okumura, M.A. Osman, J.W. Palmour, E.C. Paloura, M. Palummo, A. Paoletti, A.M. Papon, P. Paroli, M. Parrinello, G. Pensl, E. Pereira, P. Perlin, J. Petalas, W. Pfeiffer, M.C. Phillips, F.G Pikus, I. Pinter, M. Pirzer, U. Pohl, U.W. Pohl, H.M. Polatoglou, A. Polian, R. Polini, B.E. Ponga, J.L. Ponthenier, S. Porowski, J.F. Prins, K.A. Prior, J. Puls, J. Qiu, A. Qteish, G. Raciukaitis, L. Reining, T. Reisinger, M. Restle, M. Righini, P. Rodríguez-Hernández, S.J. Rolfe, R. Romestain, VD. Ryzhikov, B. Sailer, D. Sander, L. Santos, T. Sasaki, M. Sawada, G. Scamarcio, M.A. Scarselli, M. Schadt, A. Schneider, J. Schneider, A. Schöner, A. Schülzgen, S. Selci, M. Shinohara, J. Simpson, L. Sorba, B. Spellmeyer, R.P. Stanley, H. Stanzl, R.A. Stein, H. Stewart, I. Suemune, G. Sulzer, T. Suski, W. Suttrop, J.F. Swenberg, M.R. Taghizadeh, S. Takeyama, T.L. Tansley, A. Tebano, P. Thurian, E. Tosatti, C. Trager-Cowan, N. Troullier, I. Tschentscher, N. Tsuboi, A. Tsujimura, K. Tsukioka, P.A. Tupenevich, K.F. Turner, H. Uchiki, M. Uhrmacher, B. Ullrich, D. Uttamchandani, C.G. Van de Walle, J. van der Weide, J.M. Van Hove, D. Vanderbilt, L. Vanzetti, D. Vasileska, J.C. Vial, H.P. Wagner, U. Wahl, H. Waldmann, CT. Walker, E.G. Wang, M.W. Wang, S.Y. Wang, Y. Wang, V. Weinhold, T. Wiehert, C. Wild, W. Witthuhn, H. Wolf, K. Wolf, M. Wörz, G.P. Yablonskii, M. Yagi, S. Yamaga, M. Yamanaka, F. Yang, S. Yoshii, A. Yoshikawa, X. Yu, W. Zeitz, and L.G. Zimin
- Published
- 1993
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3. Generation of induced pluripotent stem cells from a schizophrenia patient with heterozygous 1q21.1 deletion.
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Okumura H, Hayashi Y, Arioka Y, Kushima I, Mori D, and Ozaki N
- Abstract
1q21.1 deletion has been identified as a risk factor related to not only mental disorders such as schizophrenia, but also congenital heart defects. However, at human cellular and molecular levels, it is still not known how this variant affects brain and heart development and contributes to the onset of these diseases. Here, we generated induced pluripotent stem cells (iPSCs) from a patient with 1q21.1 deletion. The iPSCs expressed stemness markers and exhibited the ability to differentiate into three germ layers in vitro. These iPSCs will be useful tools to understand the pathophysiology of mental disorders and heart defects in humans., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier B.V.)
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- 2024
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4. Excessive cleavage of von Willebrand factor multimers by ADAMTS13 may predict the progression of transplant-associated thrombotic microangiopathy.
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Yamada S, Sakai K, Kubo M, Okumura H, Asakura H, Miyamoto T, and Matsumoto M
- Abstract
Background: Transplant-associated thrombotic microangiopathy (TA-TMA) is a fatal complication of hematopoietic stem cell transplantation and is characterized by severe thrombocytopenia, hemolytic anemia, and organ dysfunction. In response to several possible triggers, dynamic multimetric change in von Willebrand factor (VWF) may contribute to inducing microthrombi in circulation in TA-TMA., Objectives: By performing VWF multimer analysis and measuring VWF-degradation product (DP), we unraveled the relationship between multimeric changes in circulating VWF and the pathogenesis of TA-TMA., Methods: This study analyzed 135 plasma samples from 14 patients who underwent allogeneic hematopoietic stem cell transplantation at a single institute. VWF-associated markers, namely VWF:antigen (VWF:Ag), VWF-DP/VWF:Ag ratio, VWF:ristocetin cofactor activity, VWF:ristocetin cofactor activity/VWF:Ag ratio, and ADAMTS13 activity, were analyzed in these samples collected every 7 days., Results: There were 2 patients with definite thrombotic microangiopathy (TMA) and 6 patients who presented with probable TMA that did not progress to definite TMA. Each plasma sample was classified into 3 groups: definite TMA, probable TMA, and non-TMA. VWF multimer analysis showed the absence of high-molecular-weight VWF multimers in probable TMA, whereas the appearance of unusually large VWF multimers was observed in definite TMA. The median value of the VWF-DP/VWF:Ag ratio in probable TMA was elevated to 4.17, suggesting that excessive cleavage of VWF multimers by VWF cleaving enzyme, ADAMTS13, resulted in the loss of high-molecular-weight VWF multimers., Conclusion: During the transition from probable to definite TMA, drastic VWF multimer changes imply a switch from bleeding to thrombotic tendencies. Extensive VWF-DP and VWF multimer analyses provided novel insights., (© 2024 The Author(s).)
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- 2024
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5. Establishment of induced pluripotent stem cells from a patient with 16p13.11 duplication and VPS13B deletion.
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Okumura H, Arioka Y, Kushima I, Mori D, and Ozaki N
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- Humans, Cell Differentiation physiology, Neurons, Vesicular Transport Proteins genetics, Induced Pluripotent Stem Cells metabolism
- Abstract
VPS13B deletion and 16p13.11 duplication are related to mental disorders, such as schizophrenia. However, how these variants affect human neurons and contribute to the development of mental disorders is yet to be elucidated. In this study, we generated induced pluripotent stem cells (iPSCs) from a patient with 16p13.11 duplication and VPS13B deletion. The iPSCs indicated pluripotency marker expression and the differentiation capacity into three germ layers in vitro. Therefore, these iPSC lines will be useful tools to further understand the pathophysiology of mental disorders., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 The Author(s). Published by Elsevier B.V. All rights reserved.)
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- 2022
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6. Pharmacodynamic target assessment and prediction of clinically effective dosing regimen of TP0586532, a novel non-hydroxamate LpxC inhibitor, using a murine lung infection model.
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Fujita K, Takata I, Yoshida I, Honma Y, Okumura H, Otake K, Takashima H, and Sugiyama H
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- Animals, Enterobacteriaceae, Humans, Lung, Mice, Microbial Sensitivity Tests, Anti-Bacterial Agents pharmacology, Anti-Bacterial Agents therapeutic use, Klebsiella pneumoniae
- Abstract
Introduction: TP0586532 is a novel non-hydroxamate UDP-3-O-acyl-N-acetylglucosamine deacetylase (LpxC) inhibitor. Pharmacokinetic/pharmacodynamic (PK/PD) indices and magnitude of index that correlated with the efficacy of TP0586532 were determined and used to estimate the clinically effective doses of TP0586532., Methods: Dose-fractionation studies were conducted using a murine neutropenic lung infection model caused by carbapenem-resistant Enterobacteriaceae. The relationships between the efficacy and the PK/PD index (the maximum unbound plasma concentration divided by the MIC [fC
max /MIC], the area under the unbound plasma concentration-time curve from 0 to 24 h divided by the MIC, and the cumulative percentage of a 24-h period that the unbound plasma concentration exceeds the MIC) were determined using an inhibitory sigmoid maximum-effect model. In addition, the magnitudes of fCmax /MIC were evaluated using the dose-response relationships for each of the seven carbapenem-resistant strains of Enterobacteriaceae. Furthermore, the clinically effective doses of TP0586532 were estimated using the predicted human PK parameters, the geometric mean of fCmax /MIC, and the MIC90 for carbapenem-resistant Klebsiella pneumoniae., Results: The PK/PD index that best correlated with the efficacy was the fCmax /MIC. The geometric means of the fCmax /MIC associated with the net stasis and 1-log reduction endpoints were 2.30 and 3.28, respectively. The clinically effective doses of TP0586532 were estimated to be 1.24-2.74 g/day., Conclusion: These results indicate the potential for TP0586532 to have clinical efficacy at reasonable doses against infections caused by carbapenem-resistant Enterobacteriaceae. This study provided helpful information for a clinically effective dosing regimen of TP0586532., (Copyright © 2022 Japanese Society of Chemotherapy and The Japanese Association for Infectious Diseases. Published by Elsevier Ltd. All rights reserved.)- Published
- 2022
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7. Imaging findings of a case of intravascular large B-cell lymphoma with cardiac involvement.
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Kadoya Y, Nagaoka S, Kanatani M, Nagaoka R, Maekawa N, Terada N, Nakagawa N, Kajikawa S, Okumura H, and Ishizawa S
- Abstract
Intravascular large B-cell lymphoma (IVLBCL) is a very rare subtype of malignant lymphoma that is difficult to diagnose. Cases of myocardial infarction caused by IVLBCL are even rarer. Herein, we report a case presenting with heart failure and delayed enhancement in the hypokinetic cardiac septum on contrast-enhanced cardiac magnetic resonance imaging. Myocardial biopsy showed large B-cell lymphoma cells in the microvessels within the myocardium. To the best of our knowledge, this is the first report of imaging findings of cardiac involvement in IVLBCL., (© 2021 The Authors. Published by Elsevier Inc. on behalf of University of Washington.)
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- 2021
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8. 6-Hydroxyindole is an endogenous long-lasting OATP1B1 inhibitor elevated in renal failure patients.
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Masuo Y, Fujita KI, Mishiro K, Seba N, Kogi T, Okumura H, Matsumoto N, Kunishima M, and Kato Y
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- Biological Transport, Dose-Response Relationship, Drug, Estrone analogs & derivatives, Estrone metabolism, HEK293 Cells, Hepatocytes metabolism, Humans, Indoles blood, Kinetics, Liver-Specific Organic Anion Transporter 1 genetics, Liver-Specific Organic Anion Transporter 1 metabolism, Renal Insufficiency diagnosis, Renal Insufficiency physiopathology, Up-Regulation, Uremia diagnosis, Uremia physiopathology, Hepatocytes drug effects, Indoles pharmacology, Liver-Specific Organic Anion Transporter 1 antagonists & inhibitors, Renal Insufficiency blood, Uremia blood
- Abstract
The hepatic uptake transporter organic anion transporting polypeptide (OATP) 1B1 is inhibited by some uremic toxins; however, direct inhibition can only partially explain the delayed systemic elimination of substrate drugs in renal failure patients. This study aimed to examine the long-lasting inhibition of OATP1B1 by uremic toxins and their metabolites. Preincubation of HEK293/OATP1B1 cells with 21 uremic toxins resulted in almost no change in the uptake of a typical substrate [
3 H]estrone-3-sulfate (E1 S), although some directly inhibited [3 H]E1 S uptake. In contrast, preincubation with an indole metabolite, 6-hydroxyindole, reduced [3 H]E1 S uptake, even after the inhibitor was washed out before [3 H]E1 S incubation. Such long-lasting inhibition by 6-hydroxyindole was time-dependent and recovered after a 3-h incubation without 6-hydroxyindole. Preincubation with 6-hydroxyindole increased the Km for [3 H]E1 S uptake with minimal change in Vmax. This was compatible with no change in the cell-surface expression of OATP1B1, as assessed by a biotinylation assay. Preincubation with 6-hydroxyindole reduced [3 H]E1 S uptake in human hepatocytes without changes in OATP1B1 mRNA. Plasma concentration of 6-hydroxyindole in renal failure patients increased as renal function decreased, but might be insufficient to exhibit potent OATP1B1 inhibition. In conclusion, 6-hydroxyindole is an endogenous long-lasting OATP1B1 inhibitor with elevated plasma concentrations in renal failure patients., Competing Interests: Declaration of competing interest The authors report no declaration of interest., (Copyright © 2020 The Japanese Society for the Study of Xenobiotics. Published by Elsevier Ltd. All rights reserved.)- Published
- 2020
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9. Cost-effectiveness analysis of fidaxomicin for the treatment of Clostridioides (Clostridium) difficile infection in Japan.
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Okumura H, Ueyama M, Shoji S, and English M
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- Aged, Anti-Bacterial Agents therapeutic use, Clinical Trials, Phase III as Topic, Clostridioides difficile, Clostridium Infections drug therapy, Drug Costs, Drug Utilization Review, Female, Fidaxomicin therapeutic use, Humans, Japan, Length of Stay, Male, Metronidazole therapeutic use, Middle Aged, Network Meta-Analysis, Quality-Adjusted Life Years, Randomized Controlled Trials as Topic, Recurrence, Vancomycin therapeutic use, Clostridium Infections economics, Cost-Benefit Analysis, Fidaxomicin economics, Vancomycin economics
- Abstract
Background: The cost of treating Clostridioides difficile infection (CDI), particularly recurrent disease, is high. In clinical trials, fidaxomicin has been associated with significantly lower recurrence rates and higher sustained cure rates versus vancomycin. The high acquisition cost of fidaxomicin has limited its acceptance into clinical practice., Objective: To evaluate the cost-effectiveness of fidaxomicin versus vancomycin in patients with CDI after failure of metronidazole in the Japanese healthcare setting., Methods: Clinical results from three phase III trials and inputs based on assumptions validated by clinical experts in Japan were used in a semi-Markov model with 1-year time horizon. Incremental cost-effectiveness ratios (ICERs) for fidaxomicin versus vancomycin were expressed as cost per quality-adjusted life year (QALY) and interpreted using willingness-to-pay thresholds of JPY 5,000,000 (primary) and JPY 7,500,000 (secondary) per QALY gained in Japan. Probabilistic sensitivity analyses and scenario analyses were performed., Results: Higher drug acquisition costs for fidaxomicin were partially offset by lower hospitalization costs driven by fewer recurrences, lower costs of complications, and fewer general practitioner visits versus vancomycin. The ICER for fidaxomicin versus vancomycin was estimated at JPY 5,715,183 per QALY gained. Sensitivity analyses showed a 46% probability of fidaxomicin being cost-effective versus vancomycin at a willingness-to-pay threshold of JPY 5,000,000 per QALY gained. At a threshold of JPY 7,500,000, there was a 54% probability of fidaxomicin being cost-effective., Conclusions: Fidaxomicin treatment in patients with CDI following failure of metronidazole improves health outcomes with partial offset of higher drug acquisition costs versus vancomycin., (Copyright © 2020 Japanese Society of Chemotherapy and The Japanese Association for Infectious Diseases. Published by Elsevier Ltd. All rights reserved.)
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- 2020
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10. Blunt Occlusive Traumatic Injury in the Popliteal Artery Revascularized by Stent Graft and Distal Puncture.
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Ikemura N, Kimura M, Matubara Y, Ito D, Yoshihara Y, Okumura H, and Sawada T
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- Humans, Male, Popliteal Artery diagnostic imaging, Popliteal Artery injuries, Popliteal Artery physiopathology, Punctures, Treatment Outcome, Vascular Patency, Vascular System Injuries diagnostic imaging, Vascular System Injuries physiopathology, Wounds, Nonpenetrating diagnostic imaging, Wounds, Nonpenetrating physiopathology, Young Adult, Blood Vessel Prosthesis, Blood Vessel Prosthesis Implantation instrumentation, Endovascular Procedures instrumentation, Popliteal Artery surgery, Stents, Vascular System Injuries surgery, Wounds, Nonpenetrating surgery
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- 2020
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11. Fidaxomicin compared with vancomycin and metronidazole for the treatment of Clostridioides (Clostridium) difficile infection: A network meta-analysis.
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Okumura H, Fukushima A, Taieb V, Shoji S, and English M
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- Clostridioides difficile, Humans, Recurrence, Treatment Outcome, Anti-Bacterial Agents therapeutic use, Clostridium Infections drug therapy, Fidaxomicin therapeutic use, Metronidazole therapeutic use, Vancomycin therapeutic use
- Abstract
We conducted a systematic review of the literature and network meta-analysis (NMA) to compare the relative effectiveness of antibiotic treatments for Clostridioides (Clostridium) difficile infection (CDI) including vancomycin (VCM), metronidazole (MTZ) and fidaxomicin (FDX). Eligible studies were randomised controlled trials (RCTs) including adults with any severity of CDI that was treated with VCM, MTZ or FDX. The NMA was performed using a Bayesian framework, using a fixed-effects model. The searches identified seven publications for inclusion, which provided five RCTs for VCM versus MTZ, and three RCTs for FDX versus VCM. The NMA showed that for clinical cure rate, there was no difference for FDX versus VCM, and there was a significant difference in favour of FDX versus MTZ (odds ratio [OR]: 1.77; 95% credible interval [CrI] 1.11, 2.83]). For recurrence rate, there was a significant difference in favour of FDX versus both VCM (OR: 0.50; 95% CrI: 0.37, 0.68) and MTZ (OR: 0.44; 95% CrI: 0.27, 0.72). For sustained cure (clinical cure without recurrence), there was a significant difference in favour of FDX versus VCM (OR: 1.61; 95% CrI: 1.27, 2.05) and MTZ (OR: 2.39; 95% CrI: 1.65, 3.47). These findings suggest that FDX and VCM are effective first-line treatments for mild or moderate CDI, whereas MTZ is not, and FDX may be more effective at preventing CDI recurrence than VCM., (Copyright © 2019 Japanese Society of Chemotherapy and The Japanese Association for Infectious Diseases. Published by Elsevier Ltd. All rights reserved.)
- Published
- 2020
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12. An Experimental Clamping and Cutting Study of Carotid and Intracranial Stents: Preparation for Surgical Rescue in Stent Complications.
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Arai S, Mizutani T, Sugiyama T, Sumi K, Matsumoto M, Okumura H, and Shimizu K
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- Carotid Arteries surgery, Humans, In Vitro Techniques, Intracranial Aneurysm surgery, Endovascular Procedures instrumentation, Materials Testing, Stents
- Abstract
Objective: To carry out surgery safely in vessels with stents, it is essential to have knowledge of what would happen if the stents were clamped or cut. Using all stents that are permitted in Japan, we recorded with a surgical microscope the behavior of stents when they were clamped or cut and discussed the morphologic changes along with image findings., Methods: We classified carotid artery and intracranial stents as group 1A and 1B or group 2A and 2B according to the structure of stent eye: laser cut or blade. Each stent was clamped using a Yasargil aneurysm clip, bulldog forceps, and vascular forceps. Degree of closure and presence or absence of stent deformation after declamping were recorded using a surgical microscope. Furthermore, we performed morphologic evaluations using high-resolution cone-beam computed tomography. Lastly, each stent was cut; the behavior of the cut stent was recorded, and differences between stents were examined., Results: Complete clamping was confirmed both visually and based on image evaluations with bulldog forceps and vascular forceps in the groups of carotid artery stents, with the Yasargil aneurysm clip in the intracranial stents. In the blade-type stents, we found that the stents elongated during clamping, and the component wire scattered at the time of stent cutting. Furthermore, the stents could be easily separated by holding with forceps., Conclusions: Knowing the properties of each stent is essential to conduct safe surgery in response to complications. Special care must be taken when clamping and cutting blade-type stents., (Copyright © 2019 Elsevier Inc. All rights reserved.)
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- 2020
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13. Impact of transcatheter aortic valve replacement on hemodynamic status in patients with aortic stenosis and mitral stenosis: Doppler echocardiographic study.
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Kato N, Shibayama K, Omori N, Hoshina M, Makihara Y, Okumura H, Tabata M, Obunai K, Hirao K, Pellikka PA, and Watanabe H
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- Aged, Aged, 80 and over, Aortic Valve diagnostic imaging, Aortic Valve physiopathology, Aortic Valve surgery, Aortic Valve Stenosis physiopathology, Aortic Valve Stenosis surgery, Calcinosis diagnostic imaging, Calcinosis etiology, Female, Humans, Male, Mitral Valve diagnostic imaging, Mitral Valve physiopathology, Mitral Valve Stenosis physiopathology, Mitral Valve Stenosis surgery, Postoperative Period, Stroke Volume, Treatment Outcome, Aortic Valve Stenosis diagnostic imaging, Echocardiography, Doppler, Hemodynamics physiology, Mitral Valve Stenosis diagnostic imaging, Transcatheter Aortic Valve Replacement methods
- Abstract
Background: Mitral stenosis (MS) is often concomitant with aortic stenosis (AS). However, little is known about the functional status following transcatheter aortic valve replacement (TAVR) alone in patients with severe AS and MS and the impact of TAVR for AS on MS hemodynamics., Methods: We enrolled 11 patients (age 83.6±4.7 years, eight women) with severe AS and MS who underwent TAVR. We compared New York Heart Association (NYHA) functional class and mean transmitral pressure gradient (MPG), mitral valve area (MVA), and stroke volume (SV) measured by transthoracic Doppler echocardiography between baseline and after TAVR. We also examined the calcification of the mitral annulus and mitral leaflet opening., Results: NYHA functional class improved after TAVR in all 11 patients. As SV increased after TAVR (52±12mL to 63±18mL, p=0.041), MPG decreased and MVA increased (6.9±3.8mmHg to 5.1±2.5mmHg, p=0.011 for MPG and 1.12±0.25cm
2 to 1.49±0.43cm2 , p=0.035 for MVA). However, MPG increased in one patient in whom calcification extended into the entire anterior mitral leaflet (AML) and AML mobility was severely reduced., Conclusions: NYHA functional class and hemodynamic status of MS improved after TAVR in patients with severe AS and MS. TAVR might provide therapeutic efficacy for selected symptomatic severe AS patients with MS., (Copyright © 2019 Japanese College of Cardiology. Published by Elsevier Ltd. All rights reserved.)- Published
- 2019
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14. Superiority of novel automated assessment of aortic annulus by intraoperative three-dimensional transesophageal echocardiography in patients with severe aortic stenosis: Comparison with conventional cross-sectional assessment.
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Kato N, Shibayama K, Noguchi M, Makihara Y, Okumura H, Obunai K, Isobe M, Hirao K, and Watanabe H
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- Aged, Aged, 80 and over, Aorta diagnostic imaging, Aorta surgery, Aortic Valve diagnostic imaging, Aortic Valve pathology, Aortic Valve surgery, Aortic Valve Stenosis surgery, Cross-Sectional Studies, Feasibility Studies, Female, Humans, Intraoperative Period, Male, Retrospective Studies, Software, Aortic Valve Stenosis diagnostic imaging, Echocardiography, Three-Dimensional methods, Echocardiography, Transesophageal methods, Multidetector Computed Tomography methods, Transcatheter Aortic Valve Replacement methods
- Abstract
Background: Previous studies have demonstrated that three-dimensional (3D) transesophageal echocardiography (TEE) is an alternative to multi-detector computed tomography (MDCT) for aortic valve sizing in transcatheter aortic valve replacement (TAVR). However, conventional cross-sectional analysis of aortic annulus by 3D TEE has some limitations such as lengthy analytical time. A novel software for automated valve measurement has been developed for 3D TEE. We evaluated the accuracy and analytical time of aortic annular measurements using this novel automated software in the clinical setting., Methods: We retrospectively studied 43 patients with symptomatic severe aortic stenosis (AS) who underwent TAVR. All patients underwent intraoperative TEE and MDCT. We measured aortic annular area by automated, semi-automated, and cross-sectional methods using 3D TEE datasets. These measurements were compared to the corresponding MDCT reference values. We also compared the analytical time of the three methods., Results: Automated and semi-automated analyses required significantly shorter analytical time compared to cross-sectional analysis (automated: 30.1±5.79s, semi-automated: 74.1±15.0s, manual: 81.8±18.5s, p<0.05). Compared to MDCT measurement (393.7±81.0mm
2 ), annular areas measured by automated and cross-sectional methods were significantly smaller (automated: 380.6±77.1mm2 , cross-sectional: 374.7±76.8mm2 , p<0.05), while that obtained by semi-automated method was not significantly different (387.7±75.8mm2 ). Annular areas determined by semi-automated and cross-sectional analyses had narrower limits of agreement (LOA) with MDCT measurements, compared to automated analysis (automated: -68.6 to 94.7mm2 , semi-automated: -48.3 to 60.2mm2 , cross-sectional: -40.0 to 77.9mm2 ). Measurements by all three methods using 3D TEE showed high correlation with MDCT measurement (automated: r=0.86, semi-automated: r=0.94, cross-sectional: r=0.93)., Conclusions: For aortic annular measurements using 3D TEE in AS patients, semi-automated analysis using the novel automated software reduced analytical time while maintaining similar accuracy compared to the conventional cross-sectional analysis. This automated software may have acceptable feasibility in the clinical setting., (Copyright © 2018 Japanese College of Cardiology. Published by Elsevier Ltd. All rights reserved.)- Published
- 2018
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15. Accuracy and usefulness of aortic annular measurement using real-time three-dimensional transesophageal echocardiography: Comparison with direct surgical sizing.
- Author
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Nishi T, Shibayama K, Tabata M, Kato N, Noguchi M, Okumura H, Kawano Y, Nakatsuka D, Obunai K, Kobayashi Y, and Watanabe H
- Subjects
- Aged, Aortic Valve surgery, Aortic Valve Stenosis pathology, Aortic Valve Stenosis surgery, Echocardiography, Three-Dimensional methods, Echocardiography, Transesophageal methods, Female, Heart Valve Prosthesis Implantation methods, Humans, Male, Middle Aged, Organ Size, Reproducibility of Results, Retrospective Studies, Aortic Valve diagnostic imaging, Aortic Valve pathology, Aortic Valve Stenosis diagnostic imaging, Echocardiography, Three-Dimensional statistics & numerical data, Echocardiography, Transesophageal statistics & numerical data
- Abstract
Background: There is a paucity of data that demonstrates a clinical impact of anatomical measurements of the aortic annulus by three-dimensional (3D) transesophageal echocardiography (TEE) on surgical aortic valve replacement (AVR). The aim of this study is to validate the accuracy of 3D TEE measurements compared with the direct intraoperative annular diameter and to investigate an impact of 3D TEE on a prediction of AVR with aortic annular enlargement (AAE)., Methods and Results: We retrospectively enrolled 61 patients who underwent both two-dimension (2D) and 3D TEE and transthoracic echocardiography (TTE) before AVR. The annular diameters were measured noninvasively with 2D TEE (D
2D ) and TTE (DTTE ) in a classical manner and the area- and perimeter-derived annular diameters (Darea , Dperim ) were measured from using 3D TEE analysis. Intraoperative annular diameter was measured with the manufacture's sizer (Dintraope ). Darea showed the best agreement with Dintraope in the Bland-Altman analysis. Darea , Dperim , D2D , and DTTE correlated well with Dintraope (r=0.821, 0.820, 0.532, and 0.610, respectively; all p<0.001). Three patients underwent AVR with AAE and the specificity of Dperim for prediction of AAE was significantly higher than D2D (p=0.008)., Conclusions: 3D TEE measurement of aortic annular diameter showed better agreement with the direct intraoperative measurement than 2D TEE and TTE measurements. 3D TEE measurement could predict AVR with AAE more accurately than 2D TEE and TTE measurements., (Copyright © 2017 Japanese College of Cardiology. Published by Elsevier Ltd. All rights reserved.)- Published
- 2018
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16. Preoperative Embolization of Meningiomas: Differences in Surgical Operability and Histopathologic Changes Between Embosphere and N-butyl 2-cyanoacrylate.
- Author
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Arai S, Shimizu K, Yamochi T, Mizutani T, Okumura H, Nakajo T, and Matsumoto M
- Subjects
- Adult, Aged, Aged, 80 and over, Blood Loss, Surgical, Cerebral Angiography, Female, Humans, Male, Meningeal Neoplasms diagnostic imaging, Meningeal Neoplasms pathology, Meningioma diagnostic imaging, Meningioma pathology, Middle Aged, Operative Time, Retrospective Studies, Tomography, X-Ray Computed, Acrylic Resins therapeutic use, Embolization, Therapeutic, Enbucrilate therapeutic use, Gelatin therapeutic use, Meningeal Neoplasms therapy, Meningioma therapy, Preoperative Care
- Abstract
Objective: This study aimed to examine whether there is a difference in the difficulty of extirpation after use of Embosphere versus n-butyl 2-cyanoacrylate (NBCA) for the embolization of meningiomas., Methods: Study subjects were 20 patients with meningioma who underwent embolization using either NBCA or Embosphere from April 2012 to December 2016. The difficulty of extirpation was compared and assessed in terms of objective indices, such as operative duration, perioperative bleeding, and Simpson grade, and in terms of subjective indices such as "impression on operative field" and "hardness of tumors" that the surgeon assessed using 3-point scales (dry, moderate, bloody, and soft, moderate, hard, respectively). Pathologic findings, including ischemia, necrosis, and inflammatory changes, were assessed., Results: No significant differences were found between the 2 groups regarding the mean values of operative duration (P = 0.27), perioperative bleeding (P = 0.23), and Simpson grade (P = 0.39). On the other hand, there was a significant difference with respect to the "impression on operative field" and "hardness of tumors," with reports of dry (54%; P = 0.034) and soft (81%; P = 0.0001), respectively, in the Embosphere group exceeding those of the NBCA group. The pathologic findings showed that although ischemic change (P = 0.43) and necrosis (P = 0.79) were observed in both groups, perivascular inflammation was observed only in the NBCA group (P = 0.006)., Conclusions: No relative merits were found regarding objective indices, whereas the Embosphere group had superior "ease of extirpation" as reported by the surgeon., (Copyright © 2017 Elsevier Inc. All rights reserved.)
- Published
- 2018
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17. Theoretical approaches for dynamical ordering of biomolecular systems.
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Okumura H, Higashi M, Yoshida Y, Sato H, and Akiyama R
- Subjects
- Animals, Humans, Kinetics, Macromolecular Substances chemistry, Models, Chemical, Molecular Dynamics Simulation, Molecular Structure, Structure-Activity Relationship, Computational Biology, Macromolecular Substances metabolism, Models, Biological
- Abstract
Background: Living systems are characterized by the dynamic assembly and disassembly of biomolecules. The dynamical ordering mechanism of these biomolecules has been investigated both experimentally and theoretically. The main theoretical approaches include quantum mechanical (QM) calculation, all-atom (AA) modeling, and coarse-grained (CG) modeling. The selected approach depends on the size of the target system (which differs among electrons, atoms, molecules, and molecular assemblies). These hierarchal approaches can be combined with molecular dynamics (MD) simulation and/or integral equation theories for liquids, which cover all size hierarchies., Scope of Review: We review the framework of quantum mechanical/molecular mechanical (QM/MM) calculations, AA MD simulations, CG modeling, and integral equation theories. Applications of these methods to the dynamical ordering of biomolecular systems are also exemplified., Major Conclusions: The QM/MM calculation enables the study of chemical reactions. The AA MD simulation, which omits the QM calculation, can follow longer time-scale phenomena. By reducing the number of degrees of freedom and the computational cost, CG modeling can follow much longer time-scale phenomena than AA modeling. Integral equation theories for liquids elucidate the liquid structure, for example, whether the liquid follows a radial distribution function., General Significance: These theoretical approaches can analyze the dynamic behaviors of biomolecular systems. They also provide useful tools for exploring the dynamic ordering systems of biomolecules, such as self-assembly. This article is part of a Special Issue entitled "Biophysical Exploration of Dynamical Ordering of Biomolecular Systems" edited by Dr. Koichi Kato., (Copyright © 2017 Elsevier B.V. All rights reserved.)
- Published
- 2018
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18. Egg-Coat and Zona Pellucida Proteins of Chicken as a Typical Species of Aves.
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Nishio S, Okumura H, and Matsuda T
- Subjects
- Amino Acid Sequence, Animals, Chick Embryo, Egg Proteins chemistry, Female, Male, Models, Biological, Ovum chemistry, Protein Conformation, Sperm-Ovum Interactions physiology, Zona Pellucida chemistry, Zona Pellucida physiology, Zona Pellucida Glycoproteins chemistry, Chickens metabolism, Chickens physiology, Egg Proteins physiology, Zona Pellucida Glycoproteins physiology
- Abstract
Birds are oviparous vertebrates in terrestrial animals. Birds' eggs accumulate mass of egg yolk during the egg development and are accordingly much larger than the eggs of viviparous vertebrates. Despite such difference in size and contents, the birds' eggs are surrounded with the egg-coat morphologically and compositionally resembling the mammalian egg-coat, zona pellucida. On the other hand, there are some differences in part between the two egg-coats, though relationships of such structural differences to any biological roles specific for the extracellular matrix of birds' eggs are not fully understood. In birds, unlike mammals, ZP proteins constituting the egg-coat are highly conserved and therefore those of chicken are described as a representative of birds. The egg-coat ZP proteins, ZP1, ZP3, and ZPD as the majors, accumulate and form the matrix by self-assembly around the egg rapidly growing in the ovarian follicle, in which ZP1 is from liver and both ZP3 and ZPD are from follicular granulosa cells. Although details of the egg-coat-sperm interaction on fertilization remain to be investigated, the lytic degradation process of egg-coat matrix for the sperm penetration has become to be clarified gradually. ZP1 is the primary target of sperm acrosin, and the limited cleavage in the specific region leading to the loss of intermolecular cross-linkages is crucial for the lysis of egg-coat matrix. Possible roles of the ZP1 with the additional sequence characteristic to birds are discussed from a viewpoint of giving both robustness and elastomeric nature to the egg-coat matrix for the birds' eggs., (Copyright © 2018 Elsevier Inc. All rights reserved.)
- Published
- 2018
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19. Tag/hybridization-based sensitive detection of polymerase chain reaction products.
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Niwa K, Oribe A, Okumura H, Shimono M, Nagai K, Hirota T, Yasue H, and Kawase M
- Subjects
- Base Sequence, DNA genetics, Humans, Limit of Detection, Molecular Sequence Data, Nucleic Acid Hybridization, Polymerase Chain Reaction methods
- Abstract
The polymerase chain reaction (PCR) is an important technology to amplify a single copy or a few copies of DNA segment in genomic DNAs, visualizing the segment as DNA fragment. Thus, PCR is frequently used in various examinations such as detection of bacteria and fungi in the food industry. Here, we report a simple and sensitive method for detection of PCR products using single-strand tag sequence and hybridization of the tag sequence to the complementary tag sequence immobilized on solid material (STH). The detection sensitivity was found to be at least 50 times higher than electrophoresis/ethidium bromide (EtBr) visualization for approximately a 500-bp fragment and higher than the ordinary hybridization, that is, hybridization of denatured PCR product to probe sequence immobilized on solid material., (Copyright © 2014 Elsevier Inc. All rights reserved.)
- Published
- 2014
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20. Risk factors for onset of depression after heart failure hospitalization.
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Shimizu Y, Suzuki M, Okumura H, and Yamada S
- Subjects
- Aged, Chronic Disease, Cohort Studies, Depression epidemiology, Depression prevention & control, Disease Progression, Female, Follow-Up Studies, Humans, Logistic Models, Male, Middle Aged, Multicenter Studies as Topic, Patient Care Planning, Patient Discharge, Prospective Studies, Risk Factors, Depression etiology, Depression psychology, Heart Failure complications, Heart Failure psychology, Hospitalization, Patient Participation, Patient Satisfaction, Social Support
- Abstract
Background: Depression is common in chronic heart failure (CHF) and associated with adverse outcomes. Knowing the risk factors for the development of depression at the early post-hospitalization phase may be a key factor of successful disease management programs. The aim of this study was therefore to identify the risk factors related to the onset of depression after heart failure hospitalization in patients with CHF., Methods: The study population included participants with an admission diagnosis of acute heart failure or exacerbation of CHF from a multicenter prospective cohort study. Patients completed clinical evaluation at discharge and functional and social status assessment at 1 month after discharge, and depressive symptoms using the Hospital Anxiety and Depression Scale (HADS-D) at discharge and 1-year later., Results: Of the 131 patients without depression at discharge, 29 (22.1%) had developed significant depressive symptoms (HADS-D ≥ 8) at 1-year follow-up. Multiple logistic regression demonstrated that previous ischemic heart disease [odds ratio (OR) 3.09, 95% confidence interval (CI) 1.15-8.33], participation restrictions (OR 0.43, 95% CI 0.26-0.70), and lack of satisfaction with social support (OR 0.48, 95% CI 0.29-0.79) were independent predictors of developing depression., Conclusions: The three clinically accessible variables and targets for interventions identified as predictors in this study may help to guide the optimal post-discharge disease management planning for these patients who are at high risk for depression., (Copyright © 2013 Japanese College of Cardiology. Published by Elsevier Ltd. All rights reserved.)
- Published
- 2014
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21. p53R2 is a prognostic factor of melanoma and regulates proliferation and chemosensitivity of melanoma cells.
- Author
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Matsushita S, Ikeda R, Fukushige T, Tajitsu Y, Gunshin K, Okumura H, Ushiyama M, Akiyama S, Kawai K, Takeda Y, Yamada K, and Kanekura T
- Subjects
- Adolescent, Adult, Aged, Aged, 80 and over, Cell Cycle Proteins genetics, Cell Line, Tumor, Child, Cisplatin pharmacology, Cyclin-Dependent Kinase Inhibitor p21 metabolism, Dacarbazine pharmacology, Dose-Response Relationship, Drug, Female, Gene Expression Regulation, Enzymologic, Gene Expression Regulation, Neoplastic, Humans, Immunohistochemistry, Male, Melanoma genetics, Melanoma pathology, Middle Aged, Neoplasm Invasiveness, Neoplasm Staging, Nimustine pharmacology, Prognosis, RNA Interference, Ribonucleotide Reductases genetics, Skin Neoplasms genetics, Skin Neoplasms pathology, Transfection, Vincristine pharmacology, Young Adult, Antineoplastic Agents pharmacology, Cell Cycle Proteins metabolism, Cell Proliferation drug effects, Melanoma enzymology, Ribonucleotide Reductases metabolism, Skin Neoplasms enzymology
- Abstract
Background: The treatment of melanoma, an aggressive, chemo-resistant skin cancer characterized by rapid metastasis and a poor prognosis, requires the development of innovative therapies with improved efficacy. The p53R2 gene that encodes the ribonucleotide reductase small subunit 2 homologue is induced by several stress signals including DNA-damaging agents that activate p53. The p53R2 gene product increases the deoxynucleotide triphosphate pool in the nucleus; this facilitates DNA repair and synthesis., Objective: We examined the expression of p53R2 in melanoma and evaluated whether p53R2 is involved in the growth and proliferation of melanoma cells. Methods We examined the clinicopathological significance of p53R2 in melanoma. To investigate the role of p53R2 in melanoma we used KHm5 and KHm6 melanoma cells that express p53R2, and p53R2-targeting small interfering (si) RNA., Results: p53R2 expression was detected immunohistochemically in 56 of 78 patients (71.8%). The expression of p53R2 was significantly correlated with the depth of invasion and the tumor stage. p53R2-targeting siRNA successfully knocked down p53R2 and significantly inhibited the growth of KHm5 and 6 cells. Moreover, The degree of KHm5 and 6 cell growth inhibition was greater in the presence of both p53R2-targeting siRNA and nimustine (ACNU) than with ACNU alone, suggesting that p53R2 silencing enhanced the chemosensitivity of KHm5 and 6 cells to ACNU., Conclusions: We propose p53R2 as a therapeutic target to enhance the effectiveness of chemotherapy in patients with p53R2-positive melanoma., (Copyright © 2012 Japanese Society for Investigative Dermatology. Published by Elsevier Ireland Ltd. All rights reserved.)
- Published
- 2012
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22. Diverse lectin-binding specificity of four ZP3 glycoprotein isoforms with a discrete isoelectric point in chicken egg coat.
- Author
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Okumura H, Fukushima H, Momoda M, Ima Y, Matsuda T, and Ujita M
- Subjects
- Animals, Antigens, Tumor-Associated, Carbohydrate chemistry, Antigens, Tumor-Associated, Carbohydrate metabolism, Chick Embryo, Egg Proteins blood, Egg Proteins chemistry, Fluorescent Antibody Technique, Isoelectric Point, Lectins chemistry, Membrane Glycoproteins blood, Membrane Glycoproteins chemistry, Ovum metabolism, Protein Isoforms blood, Protein Isoforms chemistry, Protein Isoforms metabolism, Receptors, Cell Surface blood, Receptors, Cell Surface chemistry, Sperm-Ovum Interactions, Zona Pellucida Glycoproteins, Egg Proteins metabolism, Lectins metabolism, Membrane Glycoproteins metabolism, Receptors, Cell Surface metabolism
- Abstract
The vertebrate egg coat corresponding to mammalian zona pellucida is a filamentous matrix composed of highly and heterogeneously glycosylated proteins designated ZP glycoproteins including ZP1 to 4, ZPD and ZPAX, and play important roles in species-specific egg-sperm interactions. Recent advance in structural biology of chicken ZP3 provided new insights into molecular mechanisms of the egg-coat function involving its carbohydrate moieties. In this study, chicken ZP3 was separated into four major and distinct isoforms with different pI in 2D-PAGE. To investigate the meanings of the ZP3 heterogeneity in egg-sperm interactions, we preliminary analyzed glycan diversity on the molecules by using lectin-staining assays. The four major ZP3 isoforms 4-7 (from acidic to basic) were recognized equally with PNA (Galβ1-3GalNAc), but the isoforms 5-7 were recognized dominantly with WGA ((β-GlcNAc)n, clustered Sia), PHA-E (bi- and triantennary N-glycan containing Galβ1-4GlcNAcβ1-2Manα1-6) and RCA I (terminal Galβ1-4GlcNAc), respectively. Despite such sugar chain diversity among the ZP3 isoforms, a partner in the egg coat, ZP1, showed specific binding to each isoform equally. Localization of ZP1 and ZP3 in the egg-coat matrix were also analyzed., (Crown Copyright © 2012. Published by Elsevier Inc. All rights reserved.)
- Published
- 2012
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23. Randomized study of induction therapy comparing standard-dose idarubicin with high-dose daunorubicin in adult patients with previously untreated acute myeloid leukemia: the JALSG AML201 Study.
- Author
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Ohtake S, Miyawaki S, Fujita H, Kiyoi H, Shinagawa K, Usui N, Okumura H, Miyamura K, Nakaseko C, Miyazaki Y, Fujieda A, Nagai T, Yamane T, Taniwaki M, Takahashi M, Yagasaki F, Kimura Y, Asou N, Sakamaki H, Handa H, Honda S, Ohnishi K, Naoe T, and Ohno R
- Subjects
- Adolescent, Adult, Antineoplastic Combined Chemotherapy Protocols therapeutic use, Cytarabine administration & dosage, Cytarabine therapeutic use, Daunorubicin therapeutic use, Dose-Response Relationship, Drug, Humans, Idarubicin therapeutic use, Leukemia, Myeloid, Acute mortality, Middle Aged, Remission Induction methods, Survival Analysis, Young Adult, Daunorubicin administration & dosage, Idarubicin administration & dosage, Leukemia, Myeloid, Acute drug therapy
- Abstract
We conducted a multi-institutional randomized study to determine whether high-dose daunorubicin would be as effective as standard-dose idarubicin in remission-induction therapy for newly diagnosed adult patients younger than 65 years of age with acute myeloid leukemia. Of 1064 patients registered, 1057 were evaluable. They were randomly assigned to receive either daunorubicin (50 mg/m(2) daily for 5 days) or idarubicin (12 mg/m(2) daily for 3 days) in combination with 100 mg/m(2) of cytarabine by continuous infusion daily for 7 days as induction therapy. Complete remission was achieved in 407 (77.5%) of 525 patients in the daunorubicin group and 416 (78.2%) of 532 in the idarubicin group (P = .79). Patients achieving complete remission received intensive postremission therapy that consisted of either 3 courses of high-dose cytarabine or 4 courses of standard-dose therapy. Overall survival rates at 5 years were 48% for the daunorubicin group and 48% for the idarubicin group (P = .54), and relapse-free survival rates at 5 years were 41% and 41% (P = .97), respectively. Thus, high-dose daunorubicin and standard-dose idarubicin were equally effective for the treatment of adult acute myeloid leukemia, achieving a high rate of complete remission and good long-term efficacy. This study is registered at http://www.umin.ac.jp/ctrj/ as C000000157.
- Published
- 2011
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24. Expansion of donor-derived hematopoietic stem cells with PIGA mutation associated with late graft failure after allogeneic stem cell transplantation.
- Author
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Mochizuki K, Sugimori C, Qi Z, Lu X, Takami A, Ishiyama K, Kondo Y, Yamazaki H, Okumura H, and Nakao S
- Subjects
- Anemia, Aplastic genetics, Anemia, Aplastic therapy, Hematopoietic Stem Cells metabolism, Hemoglobinuria, Paroxysmal genetics, Hemoglobinuria, Paroxysmal therapy, Humans, Male, Middle Aged, Time Factors, Tissue Donors, Transplantation Chimera genetics, Transplantation, Homologous, Graft Rejection etiology, Graft Rejection genetics, Hematopoietic Stem Cell Transplantation adverse effects, Membrane Proteins genetics, Mutation
- Abstract
A small population of CD55(-)CD59(-) blood cells was detected in a patient who developed donor-type late graft failure after allogeneic stem cell transplantation (SCT) for treatment of aplastic anemia (AA). Chimerism and PIGA gene analyses showed the paroxysmal nocturnal hemoglobinuria (PNH)-type granulocytes to be of a donor-derived stem cell with a thymine insertion in PIGA exon 2. A sensitive mutation-specific polymerase chain reaction (PCR)-based analysis detected the mutation exclusively in DNA derived from the donor bone marrow (BM) cells. The patient responded to immunosuppressive therapy and achieved transfusion independence. The small population of PNH-type cells was undetectable in any of the 50 SCT recipients showing stable engraftment. The de novo development of donor cell-derived AA with a small population of PNH-type cells in this patient supports the concept that glycosyl phosphatidylinositol-anchored protein-deficient stem cells have a survival advantage in the setting of immune-mediated BM injury.
- Published
- 2008
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25. P2X7 receptor as sensitive flow sensor for ERK activation in osteoblasts.
- Author
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Okumura H, Shiba D, Kubo T, and Yokoyama T
- Subjects
- Adenosine Triphosphate analogs & derivatives, Adenosine Triphosphate pharmacology, Animals, Cell Line, Estrenes pharmacology, Mice, Osteoblasts drug effects, Proto-Oncogene Proteins c-fos genetics, Proto-Oncogene Proteins c-fos metabolism, Purinergic P2 Receptor Agonists, Purinergic P2 Receptor Antagonists, Pyrrolidinones pharmacology, RNA, Messenger metabolism, Receptors, Purinergic P2X7, Stress, Mechanical, Suramin pharmacology, Extracellular Signal-Regulated MAP Kinases metabolism, Osteoblasts metabolism, Receptors, Purinergic P2 metabolism
- Abstract
The involvement of the P2 receptor in the activation of ERK induced by a short transient fluid flow stimulation in MC3T3-E1 osteoblasts was examined in the current study. The ERK activation induced by this transient fluid flow stimulation was followed by an increase in c-fos mRNA expression. Suramin, a non-selective P2 receptor antagonist, and two different P2X7 receptor (P2X7R) antagonists, ATP analogue (oxidized ATP) and dye (Brilliant blue G), inhibited fluid flow-induced ERK activation. However, the P2Y receptor pathway inhibitor U73122 did not abolish this ERK activation. The P2X7R agonist 2',3'-O-(4-benzoylbenzoyl)-ATP (BzATP) significantly increased ERK activation and this activation could be completely inhibited by oxidized ATP and Brilliant blue G. Our results suggest that P2X7R is a highly sensitive P2 receptor for fluid flow-induced ERK activation in osteoblasts.
- Published
- 2008
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26. Cyclooxygenase-2 expression is related to prognosis in patients with esophageal squamous cell carcinoma.
- Author
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Takatori H, Natsugoe S, Okumura H, Matsumoto M, Uchikado Y, Setoyama T, Sasaki K, Tamotsu K, Owaki T, Ishigami S, and Aikou T
- Subjects
- Aged, Carcinoma, Squamous Cell mortality, Carcinoma, Squamous Cell pathology, Esophageal Neoplasms mortality, Esophageal Neoplasms pathology, Female, Humans, Immunohistochemistry, Male, Middle Aged, Prognosis, Carcinoma, Squamous Cell metabolism, Cyclooxygenase 2 biosynthesis, Esophageal Neoplasms metabolism
- Abstract
Aim: Esophageal carcinoma is one of the most aggressive malignancies. Many studies have examined various biological factors associated with the malignant potential of esophageal carcinoma. Cyclooxygenase (COX)-2 is overexpressed in various types of human malignancies, including esophageal carcinomas. Although some groups have described COX-2 expression in esophageal adenocarcinoma, few studies have reported COX-2 expression in esophageal squamous cell carcinoma (ESCC)., Methods: We immunohistochemically investigated relationships between COX-2 overexpression in surgical specimens of primary tumors in 228 patients with ESCC. Relationships between COX-2 expression and clinicopathological factors, including prognosis, were analyzed. COX-2 expressions were classified into 4 criteria: Score 0, no staining; Score 1, <10% staining; Score 2, 10-90% staining; and Score 3, >90% staining., Results: Scores of COX-2 immunoreactivity in 228 patients were as follows: Score 0, 21 of 228; Score 1, 71of 228; Score 2, 117 of 228; and Score 3, 19 of 228, respectively. COX-2 expression was significantly correlated with depth of invasion and tumor stage (p=0.03 and p=0.04, respectively). The 5-year survival rate of patients decreased significantly with increased expression of COX-2 (p=0.005). Multivariate regression analysis indicated COX-2 expression as an independent prognostic factor for ESCC., Conclusions: COX-2 overexpression was significantly correlated with depth of invasion, tumor stage and survival in ESCC. Evaluation of COX-2 expression should be useful for determining tumor properties, including prognosis, in patients with ESCC.
- Published
- 2008
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27. Association of chicken zona pellucida glycoprotein (ZP) B1 with ZPC induces formation of ZPB1-ZPC fibrous aggregates containing disulfide-bridged ZPB1 dimer.
- Author
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Okumura H, Okajima T, Nadano D, and Matsuda T
- Subjects
- Animals, Chickens, Dimerization, Female, Multiprotein Complexes metabolism, Zona Pellucida Glycoproteins, Avian Proteins metabolism, Disulfides metabolism, Egg Proteins metabolism, Glycoproteins metabolism, Membrane Glycoproteins metabolism, Receptors, Cell Surface metabolism, Zona Pellucida metabolism
- Abstract
Egg-envelope, a fibrous extracellular matrix, surrounding an oocyte is constructed from ZPC, ZPX2, both of which are secreted from ovarian granulosa cells, and ZPB1 which is secreted from liver cells and transported into ovary in birds. We report here that in vitro incubation of ZPB1 with ZPC spontaneously produced fibrous aggregates of ZPB1-ZPC hetero-complexes, which were visible under optical microscopy and morphologically resembled the aggregates obtained from mechanically decomposed chicken egg-envelope. Formation of such fibrous aggregates depended on ZPC/ZPB1 ratio, and involved ZPB1 dimerization through disulfide cross-linking, which had been found in authentic egg-envelope developed in hen's ovary. Furthermore, addition of excessive amounts of ZPC to ZPB1 produced soluble but high molecular weight hetero-complexes with increased adherence property against polystyrene ELISA plates. Thus, the specific association between ZPB1 and ZPC could play pivotal roles to initiate complex formation of hetero-polymers of ZP proteins in egg-envelope matrix construction.
- Published
- 2007
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28. Reduction of plastocyanin by tyrosine-containing oligopeptides.
- Author
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Hirota S, Okumura H, Kondoh T, Funasaki N, Takabe T, and Watanabe Y
- Subjects
- Algorithms, Hydrogen-Ion Concentration, Kinetics, Models, Molecular, Oxidation-Reduction, Protein Conformation, Spectrometry, Mass, Electrospray Ionization methods, Oligopeptides chemistry, Plastocyanin chemistry, Tyrosine chemistry
- Abstract
Oxidized plastocyanin (PC) was reduced with TyrTyrTyr and LysLysLysLysTyrTyrTyr (KKKKYYY) oligopeptides at neutral pH. The TyrTyrTyr site of the peptides provided an electron to the copper active site of PC, whereas the tetralysine site of KKKKYYY functioned as the recognition site for the negative patch of PC. The reciprocal initial rate constant (1/k(int)) increased linearly with the reciprocal TyrTyrTyr concentration and proton concentration, although the electron transfer rate decreased gradually with time. The results showed that PC was reduced by the deprotonated species of TyrTyrTyr. A linear increase of log k(int) with increase in the ionic strength was observed due to decrease in the electrostatic repulsion between negatively charged PC and deprotonated (TyrTyrTyr)(-). PC was reduced faster by an addition of KKKKYYY to the PC-TyrTyrTyr solution, although KKKKYYY could not reduce PC without TyrTyrTyr. The ESI-LCMS spectrum of the products from the reaction between PC and TyrTyrTyr showed molecular ion peaks at m/z 1015.7 and 1037.7, which suggested formation of a dimerized peptide that may be produced from the reaction of a tyrosyl radical. The results indicate that PC and the tyrosine-containing oligopeptides form an equilibrium, PC(ox)/(oligopeptide)(-)-->/<--PC(red)/(oligopeptide)(*). The equilibrium is usually shifted to the left, but could shift to the right when the produced oligopeptide radical reacts with unreacted peptides. For the reaction of PC with KKKKYYY in the absence of TyrTyrTyr, the produced KKKK(YYY)(*) radical peptide could not react with other KKKKYYY peptides, since they were positively charged. In the presence of both KKKKYYY and TyrTyrTyr, PC may interact effectively with KKKKYYY through its tetralysine site and receive an electron from its TyrTyrTyr site, where the produced KKKK(YYY)(*) may interact with TyrTyrTyr peptides.
- Published
- 2006
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29. Phenothiazine and carbazole-related compounds inhibit mitotic kinesin Eg5 and trigger apoptosis in transformed culture cells.
- Author
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Okumura H, Nakazawa J, Tsuganezawa K, Usui T, Osada H, Matsumoto T, Tanaka A, and Yokoyama S
- Subjects
- Animals, Antimitotic Agents chemistry, Carbazoles chemistry, Cell Cycle drug effects, Cell Line, Transformed, Cell Line, Tumor, Cell Survival drug effects, Humans, Molecular Structure, Phenothiazines chemistry, Rats, Structure-Activity Relationship, Antimitotic Agents pharmacology, Apoptosis drug effects, Carbazoles pharmacology, Kinesins antagonists & inhibitors, Phenothiazines pharmacology
- Abstract
The effects of phenothiazine and carbazole derivatives on the cell-cycle progression of human transformed culture cells were analyzed. After 2 days incubation, 5 microM 1-phenethylamino-3-phenothiazin-10-yl-propan-2-ol (1) induced strong mitotic arrest followed by cell death, and 20 microM 1-(3,6-dichloro-9H-carbazol-9-yl)-3-phenethylamino-2-propanol (5) and 1-(3,6-dibromo-9H-carbazol-9-yl)-3-phenethylamino-2-propanol (6) also induced cell death. The TUNEL-positive nuclei characteristic of apoptotic cell death were detected in cells treated with the compounds. We observed beta- and gamma-tubulins in the arrested cells after the addition of compound 1, and found that more than 90% of the mitotic cells exhibited the monoastral spindle instead of the normal bipolar spindle. The inhibitory effects of compounds 1, 5, and 6 on the microtubule-activated ATPase activity of mitotic kinesin Eg5, which is essential for bipolar spindle formation, were obtained. The most effective inhibitor, compound 1, had an IC(50) of 1.52 microM. We also examined their toxicities on various cell lines. Compound 1 had less toxicity with the non-transformed cell line WI-38, whereas it exhibited strong toxicity with the transformed cell lines WI38VA13, HL-60 and HeLa. On the other hand, a high dose of compound 6 caused cell death in both types of culture cells. These results suggest that compound 1, an Eg5 inhibitor, selectively kills transformed culture cells.
- Published
- 2006
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30. Effect of diesel exhaust particles on mRNA expression of viral and bacterial receptors in rat lung epithelial L2 cells.
- Author
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Ito T, Okumura H, Tsukue N, Kobayashi T, Honda K, and Sekizawa K
- Subjects
- Animals, Cell Line, Dose-Response Relationship, Drug, Epithelial Cells metabolism, Intercellular Adhesion Molecule-1 biosynthesis, Intercellular Adhesion Molecule-1 genetics, Lung cytology, Lung metabolism, Platelet Membrane Glycoproteins biosynthesis, Platelet Membrane Glycoproteins genetics, Pneumonia, Bacterial metabolism, Pneumonia, Viral metabolism, RNA, Messenger genetics, Rats, Receptors, Cell Surface genetics, Receptors, G-Protein-Coupled biosynthesis, Receptors, G-Protein-Coupled genetics, Receptors, LDL biosynthesis, Receptors, LDL genetics, Reverse Transcriptase Polymerase Chain Reaction, Up-Regulation, Air Pollutants toxicity, Epithelial Cells drug effects, Lung drug effects, RNA, Messenger biosynthesis, Receptors, Cell Surface biosynthesis, Vehicle Emissions toxicity
- Abstract
Epidemiological studies have shown that particulate matter (PM) is associated with adverse respiratory health effects. Although infection in the respiratory organ is one of the most important health risks the association of infection with PM is not fully understood. As we had hypothesized that diesel exhaust particles (DEP), one of the major component of PM, may induce the expression of receptors for viruses and bacteria at invasion sites, we studied the effect of DEP on the mRNA expression of intercellular adhesion molecule-1 (ICAM-1), low-density lipoprotein (LDL) and platelet-activating factor (PAF) receptors, which are invasion sites of virus and bacteria, on rat lung epithelial cells. The real-time quantitative polymerase chain reaction (PCR) method was used for the evaluation. All of these mRNAs were up-regulated by 3, 10, and 30 microg/ml of DEP in a concentration-dependent manner. The up-regulation of each was associated with the mRNA expression of heme oxygenase-1 (HO-1), a marker of oxidative stress. Our present results show that DEP up-regulated the mRNA expression of viral and bacterial receptors. This up-regulation might be associated with DEP-induced oxidative stress. These results thus suggest that DEP may enhance the risk of pneumonia by increasing the density of bacterial and viral invasion sites in the lungs.
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- 2006
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31. The role of salvage surgery for recurrence of esophageal squamous cell cancer.
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Natsugoe S, Okumura H, Matsumoto M, Uchikado Y, Setoyama T, Uenosono Y, Ishigami S, Owaki T, and Aikou T
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- Adult, Aged, Aged, 80 and over, Antineoplastic Agents therapeutic use, Carcinoma, Squamous Cell secondary, Chemotherapy, Adjuvant, Esophagectomy, Female, Follow-Up Studies, Humans, Lymph Node Excision, Lymphatic Metastasis pathology, Male, Middle Aged, Neoplastic Cells, Circulating pathology, Radiotherapy, Adjuvant, Retrospective Studies, Survival Rate, Time Factors, Treatment Outcome, Carcinoma, Squamous Cell surgery, Esophageal Neoplasms surgery, Neoplasm Recurrence, Local surgery, Salvage Therapy
- Abstract
Aim: A consensus treatment strategy for recurrent esophageal squamous cell cancer (ESCC) has not been established. The purpose of the present study was to analyse the mode of recurrence, and evaluate the role of surgical salvage treatment in recurrence of ESCC., Methods: Recurrence was detected in 131 of 367 consecutive patients with ESCC. We retrospectively analysed the mode of recurrence and treatment for recurrence. Recurrence was divided into four types; lymph node, hematogeneous, mixed and local. Treatments were classified into four groups; chemotherapy alone (C group), radiation therapy +/- chemotherapy (R group), surgery +/- other therapy (S group), and no therapy (N group)., Results: Of the 131 recurrences, the number of patients with lymph node, hematogeneous, mixed and local recurrence was 43, 44, 40 and 4, respectively. The number of patients in the C, R, S, N groups was 35, 35, 24 and 37, respectively. Of the 24 patients who received surgical treatment for recurrence, the number of patients with lymph node, hematogeneous, mixed and local recurrence was 11, 6, 6 and 1, respectively. The number of lesions in hematogeneous recurrence was 2 or less. The survival rate from recurrence to death in the C, R, S and N groups was 0, 3.9, 6.7 and 0%, respectively. A statistically significant difference was found in these groups (p < 0.0001)., Conclusions: Salvage surgery is one of the useful treatment tools for resectable metastatic lesions. In such cases, the number of lesions, recurrent sites and effectiveness of chemotherapy and/or radiotherapy should be carefully evaluated.
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- 2006
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32. Crystal structures of archaerhodopsin-1 and -2: Common structural motif in archaeal light-driven proton pumps.
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Enami N, Yoshimura K, Murakami M, Okumura H, Ihara K, and Kouyama T
- Subjects
- Amino Acid Sequence, Bacteriorhodopsins genetics, Crystallography, X-Ray, Cytoplasm chemistry, Cytoplasm metabolism, Halobacterium chemistry, Halobacterium genetics, Halobacterium metabolism, Models, Molecular, Molecular Sequence Data, Protein Structure, Quaternary, Protein Structure, Tertiary, Protein Subunits chemistry, Protein Subunits genetics, Protein Subunits metabolism, Proton Pumps genetics, Sequence Alignment, Structural Homology, Protein, Bacteriorhodopsins chemistry, Bacteriorhodopsins metabolism, Proton Pumps chemistry, Proton Pumps metabolism
- Abstract
Archaerhodopsin-1 and -2 (aR-1 and aR-2) are light-driven proton pumps found in Halorubrum sp. aus-1 and -2, which share 55-58% sequence identity with bacteriorhodopsin (bR), a proton pump found in Halobacterium salinarum. In this study, aR-1 and aR-2 were crystallized into 3D crystals belonging to P4(3)2(1)2 (a = b = 128.1 A, c = 117.6 A) and C222(1) (a = 122.9 A, b = 139.5 A, c = 108.1 A), respectively. In both the crystals, the asymmetric unit contains two protein molecules with slightly different conformations. Each subunit is composed of seven helical segments as seen in bR but, unlike bR, aR-1 as well as aR-2 has a unique omega loop near the N terminus. It is found that the proton pathway in the extracellular half (i.e. the proton release channel) is more opened in aR-2 than in aR-1 or bR. This structural difference accounts for a large variation in the pKa of the acid purple-to-blue transition among the three proton pumps. All the aromatic residues surrounding the retinal polyene chain are conserved among the three proton pumps, confirming a previous argument that these residues are required for the stereo-specificity of the retinal isomerization. In the cytoplasmic half, the region surrounded by helices B, C and G is highly conserved, while the structural conservation is very low for residues extruded from helices E and F. Structural conservation of the hydrophobic residues located on the proton uptake pathway suggests that their precise arrangement is necessary to prevent a backward flow of proton in the presence of a large pH gradient and membrane potential. An empty cavity is commonly seen in the vicinity of Leu93 contacting the retinal C13 methyl. Existence of such a cavity is required to allow a large rotation of the side-chain of Leu93 at the early stage of the photocycle, which has been shown to accompany water translocation across the Schiff base.
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- 2006
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33. 2-Deoxy-D-ribose inhibits hypoxia-induced apoptosis by suppressing the phosphorylation of p38 MAPK.
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Ikeda R, Che XF, Ushiyama M, Yamaguchi T, Okumura H, Nakajima Y, Takeda Y, Shibayama Y, Furukawa T, Yamamoto M, Haraguchi M, Sumizawa T, Yamada K, and Akiyama S
- Subjects
- Cell Line, Tumor, Cell Polarity drug effects, Cell Shape, Extracellular Signal-Regulated MAP Kinases metabolism, Humans, Imidazoles pharmacology, JNK Mitogen-Activated Protein Kinases metabolism, Mitochondria drug effects, Phosphorylation drug effects, Protein Transport, Pyridines pharmacology, bcl-2-Associated X Protein metabolism, Apoptosis drug effects, Cell Hypoxia, Deoxyribose pharmacology, p38 Mitogen-Activated Protein Kinases metabolism
- Abstract
An angiogenic factor, platelet-derived endothelial cell growth factor/thymidine phosphorylase (TP), stimulates the chemotaxis of endothelial cells and confers resistance to apoptosis induced by hypoxia. 2-Deoxy-d-ribose, a degradation product of thymidine generated by TP enzymatic activity, partially prevented hypoxia-induced apoptosis. 2-Deoxy-d-ribose inhibited hypoxia-induced phosphorylation of p38 mitogen-activated protein kinase (MAPK) but not c-jun NH(2)-terminal kinase/stress-activated protein kinase in human leukemia HL-60 cells. 2-Deoxy-d-ribose also suppressed the levels of Bax attached to mitochondria under hypoxic conditions. SB203580, a specific inhibitor of the p38 MAPK, suppressed the hypoxia-induced apoptosis of HL-60 cells. These findings suggest that one of the molecular bases for resistance to hypoxia-induced apoptosis conferred by 2-deoxy-d-ribose is the inhibition of the p38 signaling pathway. The expression levels of TP are elevated in many malignant solid tumors and thus the 2-deoxy-d-ribose generated by TP in these tumors may play an important role in tumor progression by preventing hypoxia-induced apoptosis.
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- 2006
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34. Chest pain and ST elevation associated with fever in patients with asymptomatic Brugada syndrome: fever and chest pain in Brugada syndrome.
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Aramaki K, Okumura H, and Shimizu M
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- Adult, Bundle-Branch Block complications, Chest Pain etiology, Fever etiology, Humans, Male, Middle Aged, Bundle-Branch Block diagnosis, Electrocardiography
- Abstract
Brugada syndrome is a disease with a high risk of sudden cardiac death. Genetic mutations of the cardiac sodium channel are linked to the characteristic electrocardiogram abnormality of Brugada syndrome. Dysfunction of the mutated sodium channel is reported to be temperature-sensitive. We experienced two patients with asymptomatic Brugada syndrome who showed significant ST elevation in precordial leads while they were in a febrile state. Moreover, these patients had chest pain during precordial ST elevation. From these cases, asymptomatic Brugada syndrome should be considered as one of differential diagnoses when we examine the patients who complained of fever and chest pain. Furthermore, we should lower the elevated body temperature in patients with Brugada syndrome, because fever caused spontaneous ST elevation leading to fatal ventricular arrhythmias.
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- 2005
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35. Crystal structures of acid blue and alkaline purple forms of bacteriorhodopsin.
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Okumura H, Murakami M, and Kouyama T
- Subjects
- Anions, Crystallography, X-Ray, Models, Molecular, Protein Conformation, Protons, Bacteriorhodopsins chemistry
- Abstract
Bacteriorhodopsin, a light-driven proton pump found in the purple membrane of Halobacterium salinarum, exhibits purple at neutral pH but its color is sensitive to pH. Here, structures are reported for an acid blue form and an alkaline purple form of wild-type bacteriorhodopsin. When the P622 crystal prepared at pH 5.2 was acidified with sulfuric acid, its color turned to blue with a pKa of 3.5 and a Hill coefficient of 2. Diffraction data at pH 2-5 indicated that the purple-to-blue transition accompanies a large structural change in the proton release channel; i.e. the extracellular half of helix C moves towards helix G, narrowing the proton release channel and expelling a water molecule from a micro-cavity in the vicinity of the retinal Schiff base. In this respect, the acid-induced structural change resembles the structural change observed upon formation of the M intermediate. But, the acid blue form contains a sulfate ion in a site(s) near Arg82 that is created by re-orientations of the carboxyl groups of Glu194 and Glu204, residues comprising the proton release complex. This result suggests that proton uptake by the proton release complex evokes the anion binding, which in turn induces protonation of Asp85, a key residue regulating the absorption spectrum of the chromophore. Interestingly, a pronounced structural change in the proton release complex was also observed at high pH; i.e. re-orientation of Glu194 towards Tyr83 was found to take place at around pH 10. This alkaline transition is suggested to be accompanied by proton release from the proton release complex and responsible for rapid formation of the M intermediate at high pH.
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- 2005
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36. Reconstruction of recurrent laryngeal nerve with involvement by metastatic node in esophageal cancer.
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Natsugoe S, Okumura H, Matsumoto M, Ishigami S, Owaki T, Nakano S, and Aikou T
- Subjects
- Adult, Aged, Carcinoma, Squamous Cell pathology, Esophageal Neoplasms pathology, Humans, Lymphatic Metastasis pathology, Male, Middle Aged, Neoplasm Invasiveness, Quality of Life, Treatment Outcome, Carcinoma, Squamous Cell surgery, Esophageal Neoplasms surgery, Laryngeal Nerve Injuries, Laryngeal Nerves surgery, Neurosurgical Procedures methods, Postoperative Complications, Plastic Surgery Procedures methods, Vocal Cord Paralysis etiology
- Abstract
Background: Recurrent laryngeal nerve paralysis represents one of the major complications in esophageal cancer surgery, and patients with esophageal cancer sometimes develop recurrent laryngeal nerve paralysis before treatment. We evaluated recurrent laryngeal nerve reconstruction in patients with lymph node metastasis infiltrating the recurrent laryngeal nerve., Methods: Five patients with preoperative recurrent laryngeal nerve paralysis as a result of involvement of metastasis were enrolled in the present study. Ansa cervicalis-recurrent laryngeal nerve anastomosis in the neck was performed in 4 patients and direct anastomosis of recurrent laryngeal nerve in the mediastinum in 1 patient., Results: Six months after surgery, 3 patients who had undergone ansa cervicalis-recurrent laryngeal nerve anastomosis in the neck displayed good quality of life without hoarseness or aspiration. The patient who underwent direct anastomosis of the recurrent laryngeal nerve in the mediastinum experienced occasional aspiration and hoarseness. The remaining patient displayed poor condition because of recurrent lung tumor, and quality of life was decreased., Conclusions: If patients with recurrent laryngeal nerve paralysis before treatment can undergo potentially curative resection with lymph node dissection, including the metastatic lymph node infiltrating the recurrent laryngeal nerve, recurrent laryngeal nerve reconstruction should be performed to improve quality of life.
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- 2005
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37. In situ detection of acetylaminofluorene-DNA adducts in human cells using monoclonal antibodies.
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Iwamoto TA, Kobayashi N, Imoto K, Yamamoto A, Nakamura Y, Yamauchi Y, Okumura H, Tanaka A, Hanaoka F, Shibutani S, Miyagawa S, and Mori T
- Subjects
- Animals, Cattle, Cell Line, DNA Damage, DNA Repair, Enzyme-Linked Immunosorbent Assay, Humans, Hybridomas immunology, Mice, Microscopy, Fluorescence, Xeroderma Pigmentosum metabolism, Acetoxyacetylaminofluorene analysis, Acetoxyacetylaminofluorene immunology, Antibodies, Monoclonal, DNA Adducts analysis, DNA Adducts immunology
- Abstract
The present study was performed to generate monoclonal antibodies capable of detecting N-acetoxy-2-acetylaminofluorene (NA-AAF)-derived DNA adducts in human cells in situ. As an immunogen, we employed NA-AAF-modified single-stranded DNA coupled electrostatically to methylated protein and we produced five different monoclonal antibodies. All of them showed strong binding to NA-AAF-modified DNA, but had undetectable or minimal binding to undamaged DNA. Competitive inhibition experiments revealed that the epitope recognized by these antibodies is N-(deoxyguanosin-8-yl)-2-acetylaminofluorene (dG-C8-AAF) in DNA, although deacetylated N-(deoxyguanosin-8-yl)-2-aminofluorene in DNA is also recognized with slightly less efficiency. In contrast, these antibodies did not bind to 3-(deoxyguanosin-N(2)-yl)-2-acetylaminofluorene in DNA or to UV-induced lesions in DNA. Interestingly, they showed only minimal binding to small AAF-nucleoside adducts (dG-C8-AAF), indicating that DNA regions flanking a DNA-bound adduct, in addition to the adduct itself, are essential for the stable binding of the antibodies. Using an enzyme-linked immunosorbent assay with the most promising antibody (AAF-1), we detected the concentration-dependent induction of NA-AAF-modified adducts in DNA from repair deficient xeroderma pigmentosum (XP) cells treated with physiological concentrations of NA-AAF. Moreover, the assay enabled to confirm that normal human cells efficiently repaired NA-AAF-induced DNA adducts but not XP-A cells. Most importantly, the formation of NA-AAF-induced DNA adducts in individual nuclei of XP cells could be clearly visualized using indirect immunofluorescence. Thus, we succeeded in establishing novel monoclonal antibodies capable of the in situ detection of NA-AAF-induced DNA adducts in human cells.
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- 2004
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38. Crystal structure of the M intermediate of bacteriorhodopsin: allosteric structural changes mediated by sliding movement of a transmembrane helix.
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Takeda K, Matsui Y, Kamiya N, Adachi S, Okumura H, and Kouyama T
- Subjects
- Allosteric Regulation, Binding Sites, Crystallography, X-Ray, Hydrogen Bonding, Kinetics, Models, Molecular, Protein Conformation, Bacteriorhodopsins chemistry
- Abstract
Structural changes in the proton pumping cycle of wild-type bacteriorhodopsin were investigated by using a 3D crystal (space group P622)prepared by the membrane fusion method. Protein-protein contacts in the crystal elongate the lifetime of the M intermediate by a factor of approximately 100,allowing high levels of the M intermediate to accumulate under continuous illumination. When the M intermediate generated at room temperature was exposed to a low flux of X-rays (approximately 10(14) photons/mm2), this yellow intermediate was converted into a blue species having an absorption maximum at 650 nm. This color change is suggested to accompany a configuration change in the retinal-Lys216 chain. The true conformational change associated with formation of the M intermediate was analyzed by taking the X-radiation-induced structural change into account. Our result indicates that, upon formation of the M intermediate, helix G move stowards the extra-cellular side by, on average, 0.5 angstroms. This movement is coupled with several reactions occurring at distal sites in the protein: (1) reorientation of the side-chain of Leu93 contacting the C13 methyl group of retinal, which is accompanied by detachment of a water molecule from the Schiff base; (2) a significant distortion in the F-G loop, triggering destruction of a hydrogen bonding interaction between a pair of glutamate groups (Glu194 and Glu204); (3) formation of a salt bridge between the carboxylate group of Glu204 and the guanidinium ion of Arg82, which is accompanied by a large distortion in the extra-cellular half of helix C; (4)noticeable movements of the AB loop and the cytoplasmic end of helix B. But, no appreciable change is induced in the peptide backbone of helices A,D, E and F. These structural changes are discussed from the viewpoint of translocation of water molecules., (Copyright 2004 Elsevier Ltd.)
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- 2004
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39. Interaction of plastocyanin with oligopeptides: effect of lysine distribution within the peptide.
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Hirota S, Okumura H, Arie S, Tanaka K, Shionoya M, Takabe T, Funasaki N, and Watanabe Y
- Subjects
- Amino Acid Sequence, Binding Sites, Cytochromes c chemistry, Electron Transport, In Vitro Techniques, Lysine chemistry, Models, Molecular, Protein Conformation, Silene, Spectrophotometry, Oligopeptides chemistry, Plastocyanin chemistry
- Abstract
We synthesized and purified four oligopeptides containing four lysines (KKKK, GKKGGKK, KKGGGKK, and KGKGKGK) as models for the plastocyanin (PC) interacting site of cytochrome f. These peptides competitively inhibited electron transfer between cytochrome c and PC. The inhibitory effect increased as the peptide concentrations were increased. The association constants between PC and the peptides did not differ significantly (3500-5100 M(-1)), although the association constant of PC-KGKGKGK was a little larger than the constants between PC and other peptides. Changes in the absorption spectrum of PC were observed when the peptides were added to the PC solution: peaks and troughs were detected at about 460 and 630 nm and at about 560 and 700 nm, respectively, in the difference absorption spectra between the spectra with and without peptides. These changes were attributed to the structural change at the copper site of PC by interaction with the peptides. The structural change was most significant when tetralysine was used. These results show that binding of the oligopeptide to PC is slightly more efficient when lysines are distributed uniformly within the peptide, whereas the structural change of PC becomes larger when the lysines are close to each other within the peptide.
- Published
- 2004
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40. Crystal structure of the L intermediate of bacteriorhodopsin: evidence for vertical translocation of a water molecule during the proton pumping cycle.
- Author
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Kouyama T, Nishikawa T, Tokuhisa T, and Okumura H
- Subjects
- Bacteriorhodopsins genetics, Crystallography, X-Ray, Halobacterium salinarum metabolism, Hydrogen Bonding, Leucine chemistry, Leucine genetics, Models, Molecular, Photochemistry, Protein Conformation, Purple Membrane metabolism, Retinaldehyde chemistry, Schiff Bases, Bacteriorhodopsins chemistry, Halobacterium salinarum chemistry, Protons, Purple Membrane chemistry, Water chemistry
- Abstract
For structural investigation of the L intermediate of bacteriorhodopsin, a 3D crystal belonging to the space group P622 was illuminated with green light at 160 K and subsequently with red light at 100 K. This yielded a approximately 1:4 mixture of the L intermediate and the ground-state. Diffraction data from such crystals were collected using a low flux of X-rays ( approximately 2 x 10(15) photons/mm2 per crystal), and their merged data were compared with those from unphotolyzed crystals. These structural data, together with our previous data, indicate that the retinal chromophore, which is largely twisted in the K-intermediate, takes a more planar 13-cis, 15-anti configuration in the L intermediate. This configurational change, which is accompanied by re-orientation of the Schiff base N-H bond towards the intracellular side, is coupled with a large rotation of the side-chain of an amino acid residue (Leu93) making contact with the C13 methyl group of retinal. Following these motions, a water molecule, at first hydrogen-bonded to the Schiff base and Asp85, is dragged to a space that is originally occupied by Leu93. Diffraction data from a crystal containing the M intermediate showed that this water molecule moves further towards the intracellular side in the L-to-M transition. It is very likely that detachment of this water molecule from the protonated Schiff base causes a significant decrease in the pKa of the Schiff base, thereby facilitating the proton transfer to Asp85. On the basis of these observations, we argue that the vertical movement of a water molecule in the K-to-L transition is a key event determining the directionality of proton translocation in the protein.
- Published
- 2004
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41. Delayed neuronal damage related to microglia proliferation after mild spinal cord compression injury.
- Author
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Morino T, Ogata T, Horiuchi H, Takeba J, Okumura H, Miyazaki T, and Yamamoto H
- Subjects
- Animals, Basigin, Behavior, Animal, Cell Count, Disease Models, Animal, Female, In Situ Nick-End Labeling, Lectins metabolism, Membrane Glycoproteins metabolism, Microglia metabolism, Microtubule-Associated Proteins metabolism, Movement, Nerve Degeneration pathology, Nitric Oxide Synthase metabolism, Nitric Oxide Synthase Type II, Posture, Rats, Spinal Cord Compression pathology, Time Factors, Tumor Necrosis Factor-alpha metabolism, Antigens, CD, Antigens, Neoplasm, Antigens, Surface, Avian Proteins, Blood Proteins, Microglia pathology, Nerve Degeneration etiology, Spinal Cord Compression physiopathology
- Abstract
In order to investigate the mechanism of delayed progressive or secondary neuronal damage after the spinal cord injury, we developed a mild-compression injury model in the rat thoracic spinal cord. Our compression device consists of a soft silicone point of contact to the dura, in order to prevent violent injury that may cause axonal tears or hemorrhages in the spinal cord. Since rats often assume a 'standing' posture, i.e. raising head with lifting their fore-limbs, damage to the thoracic spinal cord was evaluated by measuring the frequency of 'standing', which effectively indicates hind limb function. Twenty-four hours after compression by a 20 g weight for 10 or 20 min, the standing frequency of the injured rat was almost the same as that of sham animals that underwent laminectomy without compression. However, the standing frequency decreased with time; the frequency of standing at 72 h was approximately 30-50% that of sham animals. In the compressed spinal cord tissue, microglial cells, detected by lectin staining, proliferated with time. An enormous amount of microglia was observed at 48 and 72 h after compression, although only a small amount of cells were positive to lectin staining at 24 h after the compression. These results suggest that our mild-compression spinal cord injury model showed late-onset or delayed neuronal damage that may be related to pathological microglia proliferation.
- Published
- 2003
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42. Effect of orally active prostacyclin analogue on survival in patients with chronic thromboembolic pulmonary hypertension without major vessel obstruction.
- Author
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Ono F, Nagaya N, Okumura H, Shimizu Y, Kyotani S, Nakanishi N, and Miyatake K
- Subjects
- Administration, Oral, Chronic Disease, Female, Hemodynamics, Humans, Hypertension, Pulmonary etiology, Hypertension, Pulmonary mortality, Hypertension, Pulmonary physiopathology, Male, Middle Aged, Epoprostenol administration & dosage, Epoprostenol analogs & derivatives, Hypertension, Pulmonary drug therapy, Pulmonary Embolism complications, Vasodilator Agents administration & dosage
- Abstract
Objectives: This study investigated whether treatment with beraprost sodium (BPS), an orally active prostacyclin analog, improves hemodynamics and survival in patients with peripheral-vessel chronic thromboembolic pulmonary hypertension (CTEPH), for which there is no surgical option., Background: Oral administration of BPS has been shown to improve the hemodynamics and prognosis in patients with primary pulmonary hypertension; however, whether BPS has beneficial effects in CTEPH remains unknown., Methods: Forty-three patients with peripheral-vessel CTEPH were classified into two groups: patients treated with BPS (BPS group, n = 20) and those without BPS (conventional group, n = 23). Baseline demographic and hemodynamic data did not significantly differ between the two groups., Results: BPS therapy improved New York Heart Association functional class in 10 patients (50%) and significantly decreased total pulmonary resistance from 18 +/- 6 to 15 +/- 8 Wood units (p < 0.05) [mean +/- SD]. Sixteen patients died of cardiopulmonary causes in the conventional group during a mean follow-up period of 58 +/- 45 months. In contrast, only three patients died of cardiopulmonary causes in the BPS group during a mean follow-up period of 44 +/- 30 months. The absence of BPS therapy, elevated total pulmonary resistance, heart rate, and age were independently related to the mortality by Cox proportional hazard analysis. The 1-year, 3-year, and 5-year survival rates for the BPS group were 100%, 85%, and 76%, respectively, compared to 87%, 60%, and 46% in the conventional group., Conclusions: This preliminary study suggests that oral administration of BPS may improve hemodynamics and survival in patients with peripheral-vessel CTEPH, for which there is no surgical option.
- Published
- 2003
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43. Thymidine phosphorylase inhibits apoptosis induced by cisplatin.
- Author
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Ikeda R, Furukawa T, Mitsuo R, Noguchi T, Kitazono M, Okumura H, Sumizawa T, Haraguchi M, Che XF, Uchimiya H, Nakajima Y, Ren XQ, Oiso S, Inoue I, Yamada K, and Akiyama S
- Subjects
- Caspases metabolism, Cell Fractionation, Cytochrome c Group metabolism, Doxorubicin pharmacology, Enzyme Activation, Etoposide pharmacology, Humans, Jurkat Cells, Mitochondria drug effects, Mitochondria metabolism, Proto-Oncogene Proteins metabolism, Proto-Oncogene Proteins c-bcl-2 metabolism, Thymidine Phosphorylase genetics, bcl-2-Associated X Protein, Antineoplastic Agents pharmacology, Apoptosis, Cisplatin pharmacology, Thymidine Phosphorylase metabolism
- Abstract
An angiogenic factor, platelet-derived endothelial cell growth factor/thymidine phosphorylase (PD-ECGF/TP), stimulates the chemotaxis of endothelial cells and confers resistance to apoptosis induced by hypoxia. 2-Deoxy-D-ribose, a degradation product of thymidine generated by TP, partially prevents hypoxia-induced apoptosis. TP is expressed at higher levels in tumor tissues compared to the adjacent non-neoplastic tissues in a variety of human carcinomas. High expression of TP is associated with an unfavorable prognosis. To investigate the effect of TP on cisplatin-induced apoptosis, human leukemia Jurkat cells were transfected with wild-type or mutant (L148R) TP cDNA. TP inhibited a number of steps in the cisplatin-induced apoptotic pathway, activation of caspases 3 and 9 and mitochondrial cytochrome c release. These findings suggest a mechanism by which TP confers resistance to apoptosis induced by cisplatin. Moreover, mutant TP that has no enzymatic activity also suppressed cisplatin-induced apoptosis. These findings indicate that TP has cytoprotective functions against cytotoxic agents which are independent of its enzymatic activity.
- Published
- 2003
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44. Specific damage induced by X-ray radiation and structural changes in the primary photoreaction of bacteriorhodopsin.
- Author
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Matsui Y, Sakai K, Murakami M, Shiro Y, Adachi Si, Okumura H, and Kouyama T
- Subjects
- Bacteriorhodopsins metabolism, Crystallography, X-Ray, Freezing, Models, Molecular, Photosynthetic Reaction Center Complex Proteins chemistry, Photosynthetic Reaction Center Complex Proteins metabolism, Photosynthetic Reaction Center Complex Proteins radiation effects, Protein Conformation, Purple Membrane radiation effects, Spectrophotometry methods, Synchrotrons, Temperature, Bacteriorhodopsins chemistry, Bacteriorhodopsins radiation effects, X-Rays
- Abstract
Bacteriorhodopsin, the sole membrane protein of the purple membrane of Halobacterium salinarum, functions as a light-driven proton pump. A 3-D crystal of bacteriorhodopsin, which was prepared by the membrane fusion method, was used to investigate structural changes in the primary photoreaction. It was observed that when a frozen crystal was exposed to a low flux of X-ray radiation (5 x 10(14)photons mm(-2)), nearly half of the protein was converted into an orange species, exhibiting absorption peaks at 450 nm, 478 nm and 510 nm. The remainder retained the normal photochemical activity until Asp85 in the active site was decarboxlyated by a higher flux of X-ray radiation (10(16)photons mm(-2)). The procedure of diffraction measurement was improved so as to minimize the effects of the radiation damage and determine the true structural change associated with the primary photoreaction. Our structural model of the K intermediate indicates that the Schiff base linkage and the adjacent bonds in the polyene chain of retinal are largely twisted so that the Schiff base nitrogen atom still interacts with a water molecule located near Asp85. With respect to the other part of the protein, no appreciable displacement is induced in the primary photoreaction.
- Published
- 2002
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45. Characterization of estrogenic compounds in medical polyvinyl chloride tubing by gas chromatography-mass spectrometry and estrogen receptor binding assay.
- Author
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Inoue K, Okumura H, Higuchi T, Oka H, Yoshimura Y, and Nakazawa H
- Subjects
- Butylated Hydroxytoluene analysis, Diethylhexyl Phthalate analysis, Equipment Safety, Fluorescein, Hexanols analysis, Humans, Phenols analysis, Plasticizers analysis, Polyvinyl Chloride standards, Gas Chromatography-Mass Spectrometry, Plasticizers metabolism, Polyvinyl Chloride chemistry, Receptors, Estrogen metabolism
- Abstract
Background: In 2001, the U.S. Food and Drug Administration (FDA) convened to conduct a safety assessment of a plasticizer, di(2-ethylhexyl) phthalate (DEHP), released from polyvinyl chloride (PVC) medical devices. Hospitalized patients may be exposed to high concentrations of plasticizers, antioxidants, and chemical contaminants in PVC medical devices during blood transfusion or hemodialysis, thus, making them vulnerable to more potentially adverse effects of these chemicals than healthy people. At the same time, recently, the effect of endocrine-disrupting chemicals on hospitalized patients has attracted a great deal of attention. This study aims to investigate the harmful effects of estrogenic compounds in medical PVC tubing by two approaches of gas chromatography-mass spectrometry (GC-MS) and estrogen receptor (ER) binding assay., Methods: Residual plasticizers, antioxidants, and chemical contaminants in PVC tubing were subjected to GC-MS in the full-scan mode with an original library for plastic additives. Such residual compounds in PVC tubing were screened at very low concentrations (10(-2)-10(5) nmol/l) to determine whether they competed with fluorescein-labeled estradiol for ER (alpha)., Results: DEHP, 2-ethylhexanol, butylated hydroxytoluene, and 4-nonylphenol (NP) were detected in medical PVC tubing. In addition, only NP in PVC tubing was found to bind with ER., Conclusions: The current study proves that the main residual chemical for estrogenic effect was NP in medical PVC tubing., (Copyright 2002 Elsevier Science B.V.)
- Published
- 2002
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46. Effects of continuous IV prostacyclin in a patient with pulmonary veno-occlusive disease.
- Author
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Okumura H, Nagaya N, Kyotani S, Sakamaki F, Nakanishi N, Fukuhara S, and Yutani C
- Subjects
- Adult, Dose-Response Relationship, Drug, Epoprostenol adverse effects, Exercise Test drug effects, Fatal Outcome, Humans, Infusions, Intravenous, Long-Term Care, Lung pathology, Lung Transplantation, Male, Pulmonary Circulation drug effects, Pulmonary Veno-Occlusive Disease diagnostic imaging, Pulmonary Veno-Occlusive Disease pathology, Pulmonary Wedge Pressure drug effects, Radiography, Epoprostenol administration & dosage, Pulmonary Veno-Occlusive Disease drug therapy
- Abstract
Pulmonary veno-occlusive disease (PVOD) is a rare but life-threatening disease. Although prostacyclin (PGI(2)) attenuates pulmonary hypertension and improves the prognosis in patients with primary pulmonary hypertension, little information is available regarding the effect of PGI(2) on patients with PVOD. This report describes a patient with severe PVOD who showed marked improvement in exercise capacity and pulmonary hemodynamics with continuous IV PGI(2) treatment. Furthermore, he experienced no clinical events for 12 months and survived for 25 months after the initiation of PGI(2) therapy. These results suggest that continuous IV PGI(2) therapy may serve as a bridge to transplantation in some cases of PVOD.
- Published
- 2002
- Full Text
- View/download PDF
47. Molecular basis for the inhibition of hypoxia-induced apoptosis by 2-deoxy-D-ribose.
- Author
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Ikeda R, Furukawa T, Kitazono M, Ishitsuka K, Okumura H, Tani A, Sumizawa T, Haraguchi M, Komatsu M, Uchimiya H, Ren XQ, Motoya T, Yamada K, and Akiyama S
- Subjects
- Animals, COS Cells, Caspases metabolism, Cell Hypoxia, Cytochrome c Group metabolism, Enzyme Inhibitors pharmacology, HL-60 Cells, Humans, Hypoxia-Inducible Factor 1, alpha Subunit, Membrane Potentials drug effects, Mitochondria drug effects, Mitochondria physiology, Proto-Oncogene Proteins c-bcl-2 metabolism, Thymidine Phosphorylase antagonists & inhibitors, Transcription Factors metabolism, Ubiquitin metabolism, bcl-X Protein, Antineoplastic Agents pharmacology, Apoptosis drug effects, Deoxyribose pharmacology
- Abstract
An angiogenic factor, platelet-derived endothelial cell growth factor/thymidine phosphorylase (PD-ECGF/TP), stimulates the chemotaxis of endothelial cells and confers resistance to apoptosis induced by hypoxia. 2-deoxy-D-ribose, a degradation product of thymidine generated by TP enzymatic activity partially prevented hypoxia-induced apoptosis. 2-Deoxy-D-ribose inhibits a number of components of the caspase-mediated hypoxia-induced apoptotic pathway. It inhibits hypoxia-induced caspase 3 activation, mitochondrial cytochrome c release, downregulation of Bcl-2 and Bcl-x(L), upregulation of hypoxia-inducible factor (HIF)-1 alpha, and loss of mitochondrial transmembrane potential in human leukemia HL-60 cell line. These findings suggest a molecular mechanism by which 2-deoxy-d-ribose confers the resistance to apoptosis. Thus 2-deoxy-D-ribose-modulated suppression of HIF-1 alpha expression could prevent the hypoxia-induced decrease of the anti-apoptotic Bcl-2 and Bcl-x(L) on the mitochondria. 2-Deoxy-L-ribose and its analogs may enhance apoptosis and suppress the growth of tumors by competitively inhibiting the activities of 2-deoxy-d-ribose and thus these analogs show promise for anti-tumor therapy.
- Published
- 2002
- Full Text
- View/download PDF
48. Primary culture system of adrenocortical cells from dogs to evaluate direct effects of chemicals on steroidogenesis.
- Author
-
Morishita K, Okumura H, Ito N, and Takahashi N
- Subjects
- Adrenal Cortex cytology, Adrenal Cortex metabolism, Aminoglutethimide toxicity, Animals, Cell Survival drug effects, Cells, Cultured, Chromatography, High Pressure Liquid, Dogs, Female, Ketoconazole toxicity, Metyrapone toxicity, Miconazole toxicity, Mitotane toxicity, Toxicity Tests methods, Adrenal Cortex drug effects, Adrenal Cortex Hormones biosynthesis
- Abstract
The present study was conducted to confirm the usefulness of a primary culture system of adrenocortical cells from dogs for detecting the direct effects of the chemicals on adrenal cortex. Corticosteroid levels in the culture supernatant were measured using high-performance liquid chromatography (HPLC) following 24-h incubation with the chemicals. Ketoconazole, miconazole, metyrapone, aminoglutethimide, and 1-(o-chlorophenyl)-1-(p-chlorophenyl)-2,2-dichloroethane (o,p-DDD), which were known to inhibit cortisol production were evaluated in this system. Both viable cells and corticosteroid levels were decreased by o,p-DDD treatment. Other chemicals showed various inhibition patterns of corticosteroid levels as follows without affecting cell viability. Ketoconazole decreased total corticosteroids level by mainly due to the decreases in cortisol and 11-deoxycortisol levels. Miconazole decreased cortisol and 11-deoxycortisol levels, however, slightly increased corticosterone level. Metyrapone decreased cortisol and corticosterone levels as 11-deoxycortisol and 11-deoxycorticosterone levels were increased. Aminoglutethimide decreased total corticosteroids level by mainly decreasing cortisol, corticosterone and 11-deoxycortisol levels. These results suggested that determination of the pattern of corticosteroid levels by HPLC in this system well reflected the mode of their action on steroidogenesis. Thus, we conclude this simple system was useful to determine the direct effects of chemicals on steroidogenesis in the adrenal cortex.
- Published
- 2001
- Full Text
- View/download PDF
49. Distal plantar area reconstruction using a flexor digitorum brevis muscle flap with reverse-flow lateral plantar artery.
- Author
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Sakai N, Yoshida T, and Okumura H
- Subjects
- Aged, Female, Humans, Treatment Outcome, Bone Neoplasms surgery, Foot Diseases surgery, Melanoma surgery, Orthopedic Procedures methods, Surgical Flaps blood supply
- Abstract
It is difficult to resurface skin defects of the sole because of its unique anatomy, which is resistant to mechanical stimuli. Though various methods have been reported, few are functionally satisfactory, and it is especially difficult to repair the distal plantar area. We report a reconstruction of the distal plantar area using a flexor digitorum brevis muscle flap based on a reverse-flow lateral plantar artery pedicle in a patient with a malignant melanoma on the right lateral metatarsal head of the fifth toe. The muscle flap was sufficient to cover the exposed fifth metatarsal and was covered with a full-thickness skin graft. The result was favourable and the patient has a normal gait and no pressure sores.
- Published
- 2001
- Full Text
- View/download PDF
50. Functional comparison between YCF1 and MRP1 expressed in Sf21 insect cells.
- Author
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Ren XQ, Furukawa T, Chen ZS, Okumura H, Aoki S, Sumizawa T, Tani A, Komatsu M, Mei XD, and Akiyama S
- Subjects
- Adenosine Triphosphate metabolism, Animals, Baculoviridae genetics, Base Sequence, Cell Line, DNA Primers, Leukotriene C4 metabolism, Recombinant Proteins genetics, Spodoptera, ATP Binding Cassette Transporter, Subfamily B, Member 1 genetics, ATP-Binding Cassette Transporters genetics, Fungal Proteins genetics, Saccharomyces cerevisiae Proteins
- Abstract
YCF1 is a yeast vacuole membrane transporter involved in resistance to Cd(2+) and to exogenous glutathione S-conjugate precursors. MRP1 contributes to multidrug resistance (MDR) in tumor cells. MRP1 and YCF1 have extensive amino acid sequence homology (63% amino acid similarity). We expressed MRP1 or YCF1 in insect cell membranes and compared their functions to know more about their structure-function relationships. YCF1 and MRP1 with His epitopes were expressed in Sf21 insect cells; both of them in the plasma membrane. The ATP-dependent transport of [(3)H]LTC(4) in Sf/YCF1-His vesicles was osmotically sensitive and showed saturable kinetics with an apparent K(m) of 758 nM for LTC(4) and 94 microM for ATP which were similar to those in yeast cells. The K(m) of YCF1 for LTC(4) (758 nM) was sevenfold higher than that of MRP1 (108 nM). MK-571 and ONO-1078, reversing agents for MRP1-mediated MDR, considerably inhibited the transport of LTC(4) by both YCF1 and MRP1. However, PAK-104P, a pyridine analog that reverses MDR associated with P-gp and MRP1, inhibited the transporting activity of MRP1 stronger than that of YCF1. KE1, another MDR reversing agent, moderately inhibited the transport of LTC(4) by MRP1 but not that of YCF1. In conclusion, we successfully expressed yeast YCF1 in Sf21 insect cells and found that the localization of the protein was different from that in yeast. The function of YCF1 in Sf21 insect cells was similar but not identical to that of MRP1., (Copyright 2000 Academic Press.)
- Published
- 2000
- Full Text
- View/download PDF
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