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Shinoda M, Itano O, Obara H, Kitagoo M, Hibi T, Abe Y, Yagi H, Matsubara K, Yamada Y, Fujino A, Hoshino K, Kuroda T, Kitagawa Y. P-136 De novo malignancy after living donor liver transplantation. Ann Oncol 2015. [DOI: 10.1093/annonc/mdv233.136] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Sakamoto Y, Nakamura M, Tobita K, Utoh H, Someya Y, Hoshino K, Asakura N, Tokunaga S. Relationship between net electric power and radial build of DEMO based on ITER steady-state scenario parameters. FUSION ENGINEERING AND DESIGN 2014. [DOI: 10.1016/j.fusengdes.2014.04.032] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Ueno T, Wada M, Hoshino K, Uemoto S, Taguchi T, Furukawa H, Fukuzawa M. Impact of Intestinal Transplantation for Intestinal Failure in Japan. Transplant Proc 2014; 46:2122-4. [DOI: 10.1016/j.transproceed.2014.06.037] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Shinoda M, Tanabe M, Itano O, Obara H, Kitago M, Abe Y, Hibi T, Yagi H, Fujino A, Kawachi S, Hoshino K, Kuroda T, Kitagawa Y. Left-Side Hepatectomy in Living Donors: Through a Reduced Upper-Midline Incision for Liver Transplantation. Transplant Proc 2014; 46:1400-6. [DOI: 10.1016/j.transproceed.2013.12.061] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2013] [Revised: 10/23/2013] [Accepted: 12/16/2013] [Indexed: 12/07/2022]
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Ueno T, Wada M, Hoshino K, Sakamoto S, Furukawa H, Fukuzawa M. A national survey of patients with intestinal motility disorders who are potential candidates for intestinal transplantation in Japan. Transplant Proc 2014; 45:2029-31. [PMID: 23769101 DOI: 10.1016/j.transproceed.2013.01.092] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2012] [Accepted: 01/24/2013] [Indexed: 12/21/2022]
Abstract
Intestinal motility disorders are a major cause of intestinal failure. Severe cases such as idiopathic pseudo-obstruction represent life-threatening illnessed. Intestinal transplantation is a treatment for severe motility disorders with irreversible intestinal failure. However, the prevalence of severe motility disorders is unknown. We performed a national survey to identify patients with intestinal motility disorders who require an intestinal transplant. The national survey of 302 institutions treating intestinal motility disorders identified 147 patients treated from 2006 to 2011 at 46 institutions. The mean patient age was 12.1 years (range, 0.3-77.5). The mean age of onset was 3.0 years (range, 0.0-68.8). Diagnoses included chronic idiopathic intestinal pseudo-obstruction (n = 96), Hirschsprung disease (n = 29), megacystis microcolon intestinal hypoperistalsis syndrome (n = 18), and other (n = 6). There were 126 survivors and 21 patients who died during the last 5 years. The mortality rate was 14.3%. Eighty-five percent of patients required parenteral nutrition for more than 6 months, which was defined as irreversible intestinal failure. Among surviving patients with irreversible intestinal failure, 8 (9.4 %) developed hepatic failure with jaundice and 27 (31.8%) 2 or more central vein thromboses. In all, at least 35 patients (41%) with irreversible failure due to intestinal motility disorders may be candidates for transplantation. The prevalence of severe intestinal motility disorders was elucidated in Japan. Severe cases should be referred to transplant centers.
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Nakamura Y, Ishikura H, Ichiki R, Hoshino K, Mizunuma M, Tanaka J, Murai A. Usefulness of presepsin and procalcitonin levels in the diagnosis of sepsis in patients with acute kidney injury. Crit Care 2014. [PMCID: PMC4068769 DOI: 10.1186/cc13403] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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Kobayashi T, Itoh K, Ido T, Kamiya K, Itoh SI, Miura Y, Nagashima Y, Fujisawa A, Inagaki S, Ida K, Hoshino K. Spatiotemporal structures of edge limit-cycle oscillation before L-to-H transition in the JFT-2M tokamak. PHYSICAL REVIEW LETTERS 2013; 111:035002. [PMID: 23909334 DOI: 10.1103/physrevlett.111.035002] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/26/2013] [Indexed: 06/02/2023]
Abstract
In this Letter, we report analyses of spatiotemporal dynamics of turbulence and structure in the limit-cycle oscillation (LCO) that precedes an L-to-H transition. Zonal flows are not observed during LCO, and the oscillation is the periodic generations or decays of barrier with edge-localized mean flow. Oscillatory Reynolds stress is found to be too small to accelerate the LCO flow, by considering the dielectric constant in magnetized toroidal plasmas. Propagation of changes of the density gradient and turbulence amplitude into the core is also observed.
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Hosokawa S, Munejiri S, Inui M, Kajihara Y, Pilgrim WC, Ohmasa Y, Tsutsui S, Baron AQR, Shimojo F, Hoshino K. Transverse excitations in liquid Sn. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2013; 25:112101. [PMID: 23378432 DOI: 10.1088/0953-8984/25/11/112101] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Transverse acoustic (TA) excitation modes were observed in inelastic x-ray scattering (IXS) spectra of liquid Sn. The excitation energies and widths of the TA modes are in good agreement with results of an ab initio molecular dynamics simulation. By comparing current correlation spectra between the experimental and theoretical results quantitatively, we have concluded that the TA modes can be detected experimentally through the quasi-TA branches in the longitudinal current correlation spectra. The lifetime and propagation length of the TA modes were determined to be ~0.7 ps and 0.8-1.0 nm, respectively, corresponding to the size of cages formed instantaneously in liquid Sn.
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Umemura T, Ishikura H, Nakamura Y, Hoshino K, Nishida T, Kamitani T. Defining the need for a massive transfusion in severe blunt traumatic patients. Crit Care 2013. [PMCID: PMC3642576 DOI: 10.1186/cc12305] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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Horie M, Meguro R, Hoshino K, Ishida N, Norita M. Neuroanatomical study on the tecto-suprageniculate-dorsal auditory cortex pathway in the rat. Neuroscience 2013; 228:382-94. [DOI: 10.1016/j.neuroscience.2012.10.047] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2012] [Revised: 10/10/2012] [Accepted: 10/23/2012] [Indexed: 10/27/2022]
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Hoshino K, Shibata D, Miyagi T, Yamamoto Y, Arakaki S, Maeshiro T, Hokama A, Kinjo F, Takahashi K, Fujita J. Cytomegalovirus-associated gastric ulcers in a patient with dermatomyositis treated with steroid and cyclophosphamide pulse therapy. Endoscopy 2012; 43 Suppl 2 UCTN:E277-8. [PMID: 21915824 DOI: 10.1055/s-0030-1256422] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
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Shinoda M, Tanabe M, Kawachi S, Itano O, Obara H, Kitago M, Matsubara K, Shimojima N, Fuchimoto Y, Hoshino K, Kuroda T, Kitagawa Y. Video-assisted Living Donor Lateral Segmentectomy and Left Hepatectomy Through a Reduced Upper Midline Incision for Liver Transplantation. J Surg Res 2012. [DOI: 10.1016/j.jss.2011.11.208] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
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Muro Y, Sugiura K, Hoshino K, Akiyama M. Disappearance of anti-MDA-5 autoantibodies in clinically amyopathic DM/interstitial lung disease during disease remission. Rheumatology (Oxford) 2011; 51:800-4. [DOI: 10.1093/rheumatology/ker408] [Citation(s) in RCA: 79] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Uemura H, Hoshino K, Kubota Y. Engagement of Renin-Angiotensin System in Prostate Cancer. Curr Cancer Drug Targets 2011; 11:442-50. [DOI: 10.2174/156800911795538101] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2010] [Accepted: 03/13/2011] [Indexed: 11/22/2022]
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Yamane A, Shimojo F, Hoshino K, Ichikawa T, Kojima Y. Ab initio study on the hydrogen desorption from MH-NH3 (M = Li, Na, K) hydrogen storage systems. J Chem Phys 2011; 134:124515. [PMID: 21456684 DOI: 10.1063/1.3562122] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The hydrogen storage system LiH + NH(3) ↔ LiNH(2) + H(2) is one of the most promising hydrogen storage systems, where the reaction yield can be increased by replacing Li in LiH with other alkali metals (Na or K) in order of Li < Na < K. In this paper, we have studied the alkali metal M (M = Li, Na, K) dependence of the reactivity of MH with NH(3) by calculating the potential barrier of the H(2) desorption process from the reaction of an M(2)H(2) cluster with an NH(3) molecule based on the ab initio structure optimization method. We have shown that the height of the potential barrier becomes lower in order of Li, Na, and K, where the difference of the potential barrier in Li and Na is relatively smaller than that in Na and K, and this tendency is consistent with the recent experimental results. We have also shown that the H-H distance of the H(2) dimer at the transition state takes larger distance and the change of the potential energy around the transition state becomes softer in order of Li, Na, and K. There are almost no M dependence in the charge of the H atom in NH(3) before the reaction, while that of the H atom in M(2)H(2) takes larger negative value in order of Li, Na, and K. We have also performed molecular dynamics simulations on the M(2)H(2)-NH(3) system and succeeded to reproduce the H(2) desorption from the reaction of Na(2)H(2) with NH(3).
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Yamane A, Shimojo F, Hoshino K. Effects of system-size and inner-core 2p states on melting of dense sodium at high pressure: ab initiomolecular-dynamics simulation. EPJ WEB OF CONFERENCES 2011. [DOI: 10.1051/epjconf/20111501009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Molico E, Hoshino K. 215 ABSENCE OF REM-SLEEP INDUCED AGGRESSIVENESS IN FEMALE RATS: IS FLIGHT THEIR PREVALENT FORM OF PANIC MANIFESTATION? Sleep Med 2009. [DOI: 10.1016/s1389-9457(09)70217-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Hoshino K. Structure of liquid metals by ab initio molecular-dynamics simulations. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2009; 21:474212. [PMID: 21832491 DOI: 10.1088/0953-8984/21/47/474212] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
How the study of liquid metals has progressed in the past three decades is summarized briefly from a personal point of view. It is emphasized that, by ab initio molecular-dynamics (MD) simulations, we can now obtain the electronic states as well as the structure of liquid metals at the same time and therefore we can understand the characteristic features of the microscopic atomic structure and bonding states in real space. As examples we show the results of our ab initio MD simulations for liquid phosphorus, liquid tellurium and liquid carbon at high pressures.
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Hirabayashi T, Morikawa Y, Matsufuji H, Hoshino K, Hagane K, Ozaki K. Stimulatory action of mitemcinal (GM-611), an acid-resistant non-peptide motilin receptor agonist, on colonic motor activity and defecation: spontaneous and mitemcinal-induced giant migrating contractions during defecation in dogs. Neurogastroenterol Motil 2009; 21:1085-e91. [PMID: 19508333 DOI: 10.1111/j.1365-2982.2009.01341.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
The aim of this study was to characterize giant migrating contractions (GMCs) during spontaneous defecation in dogs and to investigate the effect of mitemcinal (an orally active and highly acid-resistant motilin receptor agonist) on colonic motility to assess the possibility of using it for the treatment of colonic motility disorders. To assess colonic motility, strain-gauge force transducers were implanted on the gastrointestinal tract of five dogs, and the behaviour of the dogs was monitored with a noctovision-video camera system. The effect of mitemcinal (0, 3, 10 or 30 mg per dog) and sennoside (300 mg per dog) on colonic motility was assessed 24 h after oral administration. During a 39-day period, the starting point of most of the 140 GMCs was between the transverse colon and the descending colon, but some variation was observed. In the daytime, the GMCs originated from somewhat more proximal positions than at night. Mitemcinal caused an increase in the GMC-index (integration of contractile amplitude and duration) and proximal translocation of the GMC starting point, but did not cause an increase in the number of defecations 12 h after administration. Sennoside, however, caused a significant increase in the number of defecations, an increase in the GMC-index, and prolongation of the duration of GMCs. The GMC starting point in the canine colon varied during spontaneous defecation. Mitemcinal was a potent prokinetic drug to mimic a spontaneous defecation compared with sennoside. Mitemcinal evacuates more intestinal luminal contents during the defecation than does sennoside.
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Muro Y, Sugiura K, Nitta Y, Mitsuma T, Hoshino K, Usuda T, Hayashi K, Murase Y, Shimizu M, Matsuo H. Scoring of reflux symptoms associated with scleroderma and the usefulness of rabeprazole. Clin Exp Rheumatol 2009; 27:15-21. [PMID: 19796556] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
OBJECTIVE The high frequency of gastroesophageal reflux disease (GERD) as a complication of scleroderma (systemic sclerosis, SSc) calls for treatment with powerful acid suppressants such as proton pump inhibitors (PPI). The present study used a GERD-specific questionnaire to assess the symptoms of GERD in SSc patients, and examine the effectiveness of rabeprazole (RPZ) for treating the symptoms of GERD. METHODS The Frequency Scale for the Symptoms of GERD (FSSG), a medical questionnaire developed in Japan for evaluating GERD, and the Visual Analogue Scale (VAS) were used to evaluate GERD symptoms and the degree of pain, respectively, in 151 SSc subjects. These tools were also used to assess the effect of 8 weeks' treatment with the PPI RPZ (10 mg/day). RESULTS Data on age and gender, and FSSG and VAS scores before treatment and after 4 and 8 weeks' RPZ treatment, were available for 84 subjects. The mean FSSG score was 13.9+/-9.7 before treatment, 8.3+/-8.1 after 4 weeks of treatment, and 7.0+/-7.0 after 8 weeks of treatment; the score reduction was significant (p<0.001) indicating the effectiveness of RPZ in improving subjective GERD symptoms. The VAS scores revealed a significant improvement in pain after both 4 and 8 weeks compared with baseline scores. Six subjects experienced adverse effects and five discontinued the analysis during the period. CONCLUSION Administration of RPZ 10 mg/day is effective for the control of the symptoms of GERD associated with SSc. In addition to assessing the symptoms of GERD, the FSSG questionnaire can be used to evaluate the therapeutic effect of drugs.
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Itoh K, Asakawa T, Hoshino K, Adachi M, Fukiya K, Watanabe N, Tanaka Y. Functional analysis of aldehyde oxidase using expressed chimeric enzyme between monkey and rat. Biol Pharm Bull 2009; 32:31-5. [PMID: 19122276 DOI: 10.1248/bpb.32.31] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Aldehyde oxidase (AO) is a homodimer with a subunit molecular mass of approximately 150 kDa. Each subunit consists of about 20 kDa 2Fe-2S cluster domain storing reducing equivalents, about 40 kDa flavine adenine dinucleotide (FAD) domain and about 85 kDa molybdenum cofactor (MoCo) domain containing a substrate binding site. In order to clarify the properties of each domain, especially substrate binding domain, chimeric cDNAs were constructed by mutual exchange of 2Fe-2S/FAD and MoCo domains between monkey and rat. Chimeric monkey/rat AO was referred to one with monkey type 2Fe-2S/FAD domains and a rat type MoCo domain. Rat/monkey AO was vice versa. AO-catalyzed 2-oxidation activities of (S)-RS-8359 were measured using the expressed enzyme in Escherichia coli. Substrate inhibition was seen in rat AO and chimeric monkey/rat AO, but not in monkey AO and chimeric rat/monkey AO, suggesting that the phenomenon might be dependent on the natures of MoCo domain of rat. A biphasic Eadie-Hofstee profile was observed in monkey AO and chimeric rat/monkey AO, but not rat AO and chimeric monkey/rat AO, indicating that the biphasic profile might be related to the properties of MoCo domain of monkey. Two-fold greater V(max) values were observed in monkey AO than in chimeric rat/monkey AO, and in chimeric monkey/rat AO than in rat AO, suggesting that monkey has the more effective electron transfer system than rat. Thus, the use of chimeric enzymes revealed that 2Fe-2S/FAD and MoCo domains affect the velocity and the quantitative profiles of AO-catalyzed (S)-RS-8359 2-oxidation, respectively.
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Kowaki Y, Harada A, Shimojo F, Hoshino K. Reconstruction of carbon atoms around a point defect of a graphene: a hybrid quantum/classical molecular-dynamics simulation. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2009; 21:064202. [PMID: 21715905 DOI: 10.1088/0953-8984/21/6/064202] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
We have investigated the rearrangement of carbon atoms around a point defect of a graphene using a hybrid ab initio/classical molecular-dynamics (MD) simulation method, in which 36 carbon atoms surrounding a point defect are treated by the ab initio MD method and the other 475 carbon atoms relatively far from the point defect are treated by the classical MD method. We have confirmed a formation of a 5-1DB defect (a pentagon and a dangling bond) from the time dependence of atomic configurations and electron density distributions obtained by our simulation. We have found that the pentagon is formed in two different positions around the point defect, and that the two positions appear alternately during the simulation, the frequency of which increases with increasing temperature.
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Hoshino K, Inouye H, Unokuchi T, Ito M, Tsuji K. HLA and Diseases in Japanese: Statistical analysis of patients from Drs. Aizawa, M. Fukunishi, T., Fujii, T., Fujimori, I., Fukuda, Y., Gonda, N., Hashimoto, K., Horiuchi, Y., Kozaki, M., Kohno, M., Matsuo, M., Miki, Y., Miyajima, T., Mori, T., Nakata, F. ACTA ACUST UNITED AC 2008. [DOI: 10.1111/j.1399-0039.1977.tb00750.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Morishita A, Hoshino K, Katahira S, Tomioka H. [Effectiveness of high frequency jet ventilation introduced immediately after cardiac surgery]. KYOBU GEKA. THE JAPANESE JOURNAL OF THORACIC SURGERY 2008; 61:1039-1042. [PMID: 19048904] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
It is important to establish the lung protective strategy strictly for serious respiratory failure after cardiac surgery, because the hemodynamic state is unstable. High frequency jet ventilation (HFJV) was introduced in 5 patients with respiratory failure after cardiac surgery. Two had been diagnosed with acute aortic dissection and 3 with angina pectorlis. Off pump coronary artery bypass grafting was performed in 2 patients. Hemodynamic variables during HFJV were stable, and the duration of HFJV was 9 to 45 hours. Oxygenations improved immediately by the introduction of HFJV in all patients, and no adverse effect was recognized. Therefore, use of HFJV immediately after cardiac surgery might be an effective respiratory therapy of choice for patients with acute lung injury.
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Itoh K, Yamamura M, Muramatsu S, Hoshino K, Masubuchi A, Sasaki T, Tanaka Y. Stereospecific oxidation of the (S)-enantiomer of RS-8359, a selective and reversible monoamine oxidase A (MAO-A) inhibitor, by aldehyde oxidase. Xenobiotica 2008; 35:561-73. [PMID: 16192108 DOI: 10.1080/00498250500202106] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
In a previous paper by the authors on RS-8359, a new selective and reversible monoamine oxidase A (MAO-A) inhibitor, it was reported that the (S)-enantiomer of RS-8359 is rapidly eliminated from rats, monkeys and humans as a result of the formation of a 2-oxidative metabolite. The present study investigates the properties of the enzyme responsible for the 2-oxidation of RS-8359. Subcellular localization, cofactor requirement and the inhibitory effects of typical compounds were studied using rat liver preparations. In addition, the enzyme was purified from rat liver cytosol for further characterization. The enzyme activity was localized in the cytosolic fraction without the need for any cofactor and was extensively inhibited by menadione, chlorpromazine and quinacrine. The purified enzyme was also a homodimer with a monomeric molecular weight of 140 kDa and it had an A280/A450 ratio of 5.1 in the absorption spectrum. The results suggest that the enzyme responsible for the biotransformation of RS-8359 to give the 2-keto derivative is aldehyde oxidase (EC 1.2.3.1). The reaction of aldehyde oxidase is highly stereoselective for the (S)-configuration of RS-8359 and the (9R)-configuration of cinchona alkaloids.
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