Network


Latest external collaboration on country level. Dive into details by clicking on the dots.

Hotspot


Dive into the research topics where Toshimitsu Hamasaki is active.

Publication


Featured researches published by Toshimitsu Hamasaki.


The Lancet | 2007

Human atrial natriuretic peptide and nicorandil as adjuncts to reperfusion treatment for acute myocardial infarction (J-WIND): two randomised trials.

Masafumi Kitakaze; Masanori Asakura; Jiyoong Kim; Yasunori Shintani; Hiroshi Asanuma; Toshimitsu Hamasaki; Osamu Seguchi; Masafumi Myoishi; Tetsuo Minamino; Takahiro Ohara; Yoshiyuki Nagai; Shinsuke Nanto; Kouki Watanabe; Shigeru Fukuzawa; Natsuki Nakamura; Kazuo Kimura; Kenshi Fujii; Masaharu Ishihara; Yoshihiko Saito; Hitonobu Tomoike; Soichiro Kitamura

BACKGROUND Patients who have acute myocardial infarction remain at major risk of cardiovascular events. We aimed to assess the effects of either human atrial natriuretic peptide or nicorandil on infarct size and cardiovascular outcome. METHODS We enrolled 1216 patients who had acute myocardial infarction and were undergoing reperfusion treatment in two prospective, single-blind trials at 65 hospitals in Japan. We randomly assigned 277 patients to receive intravenous atrial natriuretic peptide (0.025 microg/kg per min for 3 days) and 292 the same dose of placebo. 276 patients were assigned to receive intravenous nicorandil (0.067 mg/kg as a bolus, followed by 1.67 microg/kg per min as a 24-h continuous infusion), and 269 the same dose of placebo. Median follow-up was 2.7 (IQR 1.5-3.6) years for patients in the atrial natriuretic peptide trial and 2.5 (1.5-3.7) years for those in the nicorandil trial. Primary endpoints were infarct size (estimated from creatine kinase) and left ventricular ejection fraction (gauged by angiography of the left ventricle). FINDINGS 43 patients withdrew consent after randomisation, and 59 did not have acute myocardial infarction. We did not assess infarct size in 50 patients for whom we had fewer than six samples of blood. We did not have angiographs of left ventricles in 383 patients. Total creatine kinase was 66,459.9 IU/mL per h in patients given atrial natriuretic peptide, compared with 77,878.9 IU/mL per h in controls, with a ratio of 0.85 between these groups (95% CI 0.75-0.97, p=0.016), which indicated a reduction of 14.7% in infarct size (95% CI 3.0-24.9%). The left ventricular ejection fraction at 6-12 months increased in the atrial natriuretic peptide group (ratio 1.05, 95% CI 1.01-1.10, p=0.024). Total activity of creatine kinase did not differ between patients given nicorandil (70 520.5 IU/mL per h) and controls (70 852.7 IU/mL per h) (ratio 0.995, 95% CI 0.878-1.138, p=0.94). Intravenous nicorandil did not affect the size of the left ventricular ejection fraction, although oral administration of nicorandil during follow-up increased the left ventricular ejection fraction between the chronic and acute phases. 29 patients in the atrial natriuretic peptide group had severe hypotension, compared with one in the corresponding placebo group. INTERPRETATION Patients with acute myocardial infarction who were given atrial natriuretic peptide had lower infarct size, fewer reperfusion injuries, and better outcomes than controls. We believe that atrial natriuretic peptide could be a safe and effective adjunctive treatment in patients with acute myocardial infarction who receive percutaneous coronary intervention.


Circulation Research | 2013

Circulating p53-Responsive MicroRNAs Are Predictive Indicators of Heart Failure After Acute Myocardial Infarction

Sen Matsumoto; Yasuhiko Sakata; Shinichiro Suna; Daisaku Nakatani; Masaya Usami; Masahiko Hara; Tetsuhisa Kitamura; Toshimitsu Hamasaki; Shinsuke Nanto; Yukio Kawahara; Issei Komuro

Rationale: Despite a recent decline of in-hospital mortality attributable to acute myocardial infarction (AMI), the incidence of ischemic heart failure (HF) in post-AMI patients is increasing. Although various microRNAs have been proposed as diagnostic indicators for AMI, no microRNAs have been established as predictors of ischemic HF that develops after AMI. Objective: We attempted to identify circulating microRNAs that can serve as reliable predictors of ischemic HF in post-AMI patients. Methods and Results: Using sera collected a median of 18 days after AMI onset, we screened microRNAs in 21 patients who experienced development of HF within 1 year after AMI and in 65 matched controls without subsequent cardiovascular events after discharge. Among the 377 examined microRNAs, the serum level of only miR-192 was significantly upregulated in AMI patients with development of ischemic HF. Because miR-192 is reported to be p53-responsive, the serum levels of 2 other p53-responsive microRNAs, miR-194 and miR-34a, also were investigated. Interestingly, both microRNAs were coordinately increased with miR-192, particularly in exosomes, suggesting that these microRNAs function as circulating regulators of HF development via the p53 pathway. Furthermore, miR-194 and miR-34a expression levels were significantly correlated with left ventricular end-diastolic dimension 1 year after AMI. Conclusions: In the sera of post-AMI patients who experienced development of de-novo HF within 1 year of AMI onset, the levels of 3 p53-responsive microRNAs had been elevated by the early convalescent stage of AMI. Further investigations are warranted to confirm the usefulness of these circulating microRNAs for predicting the risk of development of ischemic HF after AMI.


European Journal of Neuroscience | 2004

Benefit of valproic acid in suppressing disease progression of ALS model mice.

Fuminobu Sugai; Yoichi Yamamoto; Katsuyuki Miyaguchi; Zhiwei Zhou; Hisae Sumi; Toshimitsu Hamasaki; M. Goto; Saburo Sakoda

Valproic acid (VPA) has long been used as an antiepileptic drug and recently as a mood stabilizer, and evidence is increasing that VPA exerts neuroprotective effects through changes in a variety of intracellular signalling pathways including upregulation of Bcl‐2 protein with an antiapoptotic property and inhibiting glycogen synthase kinase 3‐β, which is considered to promote cell survival. Although the neuroprotective effects of VPA have been demonstrated in a murine model of human immunodeficiency virus‐1 encephalitis, there have been no reports on the effect of VPA in chronic progressing neurodegenerative disease models including amyotrophic lateral sclerosis (ALS). ALS is a devastating disease selectively affecting motoneurons, and its disease model mice bear a close resemblance to ALS symptomatically and pathologically. First, we used an organotypic slice culture using mouse spinal cord, and showed that VPA protected spinal motoneurons against death from glutamate toxicity in vitro. Then, we treated ALS model mice with VPA at the dose effective level for epileptic model mice after 45 days of age (pre‐onset treatment) or the day of the disease onset (post‐onset treatment). We found a significant prolongation of the disease duration in ALS model mice in both methods of treatment. Considering the long usage of VPA for epileptic patients with good tolerance and safety, these data strongly support the clinical application of VPA for ALS treatment.


Critical Care | 2011

Treatment effects of recombinant human soluble thrombomodulin in patients with severe sepsis: a historical control study

Kazuma Yamakawa; Satoshi Fujimi; Tomoyoshi Mohri; Hiroki Matsuda; Yasushi Nakamori; Tomoya Hirose; Osamu Tasaki; Hiroshi Ogura; Yasuyuki Kuwagata; Toshimitsu Hamasaki; Takeshi Shimazu

IntroductionCross-talk between the coagulation system and inflammatory reactions during sepsis causes organ damage followed by multiple organ dysfunction syndrome or even death. Therefore, anticoagulant therapies have been expected to be beneficial in the treatment of severe sepsis. Recombinant human soluble thrombomodulin (rhTM) binds to thrombin to inactivate coagulation, and the thrombin-rhTM complex activates protein C to produce activated protein C. The purpose of this study was to examine the efficacy of rhTM for treating patients with sepsis-induced disseminated intravascular coagulation (DIC).MethodsThis study comprised 65 patients with sepsis-induced DIC who required ventilatory management. All patients fulfilled the criteria of severe sepsis and the International Society on Thrombosis and Haemostasis criteria for overt DIC. The initial 45 patients were treated without rhTM (control group), and the following 20 consecutive patients were treated with rhTM (0.06 mg/kg/day) for six days (rhTM group). The primary outcome measure was 28-day mortality. Stepwise multivariate Cox regression analysis was used to assess which independent variables were associated with mortality. Comparisons of Sequential Organ Failure Assessment (SOFA) score on sequential days between the two groups were analyzed by repeated measures analysis of variance.ResultsCox regression analysis showed 28-day mortality to be significantly lower in the rhTM group than in the control group (adjusted hazard ratio, 0.303; 95% confidence interval, 0.106 to 0.871; P = 0.027). SOFA score in the rhTM group decreased significantly in comparison with that in the control group (P = 0.028). In the post hoc test, SOFA score decreased rapidly in the rhTM group compared with that in the control group on day 1 (P < 0.05).ConclusionsWe found that rhTM administration may improve organ dysfunction in patients with sepsis-induced DIC. Further clinical investigations are necessary to evaluate the effect of rhTM on the pathophysiology of sepsis-induced DIC.


Investigative Ophthalmology & Visual Science | 2010

Ocular risk factors for choroidal neovascularization in pathologic myopia.

Yasushi Ikuno; Yukari Jo; Toshimitsu Hamasaki; Yasuo Tano

UNLABELLED PURPOSE. To identify the risk factors for development of myopic choroidal neovascularization (mCNV), a major cause of visual impairment. METHODS. Enrolled in the study were 23 consecutive patients with bilateral high myopia (axial length, > or =26.5 mm or refractive error, < or =8 D) and unilateral newly developed mCNV who presented to the Myopia Clinic, Osaka University Hospital. Spectral-domain optical coherence tomography (SD-OCT) showed that the fellow eyes had a normal macula. The parameters in the affected and fellow eyes were compared between the individual patients, including best-corrected visual acuity (BCVA), intraocular pressure (IOP), refractive error, axial length, choroidal thickness (CT) (subfoveal, 1.5 mm superiorly and inferiorly), posterior staphyloma height 3 mm from the fovea, length of retinal pigment epithelium (RPE) curvature within 6 mm measured on SD-OCT images, and choroidal degeneration and lacquer crack formation, graded according to a published METHOD RESULTS. The IOP, axial length, refractive error, and chorioretinal degeneration did not differ significantly. Affected eyes had a significantly higher lacquer crack grade (P < 0.05). The superior CT was not significantly different; the subfoveal and inferior CTs were significantly lower in the affected eyes (P < 0.05 and P < 0.001, respectively). The absolute value of the nasal posterior staphyloma height from the fovea was significantly greater in the affected eyes (P < 0.05), and the affected eyes had a significantly (P < 0.05) longer RPE curvature. CONCLUSIONS. Choroidal thinning resulting from increased RPE/choroid curvature is a risk factor for unilateral mCNV.


Circulation-cardiovascular Interventions | 2013

Endovascular Treatment for Infrainguinal Vessels in Patients With Critical Limb Ischemia OLIVE Registry, a Prospective, Multicenter Study in Japan With 12-Month Follow-up

Osamu Iida; Masato Nakamura; Yasutaka Yamauchi; Daizo Kawasaki; Yoshiaki Yokoi; Hiroyoshi Yokoi; Yoshimistu Soga; Kan Zen; Keisuke Hirano; Nobuhiro Suematsu; Naoto Inoue; Kenji Suzuki; Yoshiaki Shintani; Yusuke Miyashita; Kazushi Urasawa; Ikuro Kitano; Terutoshi Yamaoka; Takashi Murakami; Michitaka Uesugi; Taketsugu Tsuchiya; Toshiro Shinke; Yasuhiro Oba; Norihiko Ohura; Toshimitsu Hamasaki; Shinsuke Nanto

Background—Recent technical advances have made endovascular treatment (EVT) an alternative first-line treatment for critical limb ischemia. Methods and Results—A prospective multicenter study was conducted to evaluate the clinical outcomes of 314 Japanese critical limb ischemia patients (mean age, 73±10 years) with infrainguinal arterial lesions who underwent EVT. Patients were enrolled from December 2009 to July 2011 and were followed-up for 12 months. The primary end point was amputation-free survival (AFS) at 12 months. Secondary end points were anatomic, clinical, and hemodynamic measures, including 12-month freedom from major adverse limb events. The 12-month AFS rate was 74%, with body mass index <18.5 (hazard ratio [HR], 2.22; P=0.008), heart failure (HR, 1.73; P=0.04), and wound infection (HR, 1.89; P=0.03) associated with a poor prognosis for AFS. The 12-month major adverse limb event-free rate was 88%, with hemodialysis (HR, 1.98; P=0.005), heart failure (HR, 1.69; P=0.02), and Rutherford classification 6 (HR, 2.25; P=0.002) associated with a poor prognosis for major adverse limb events. The median time for wound healing was 97 days, with body mass index <18.5 (HR, 0.54; P=0.03) and wound infection (HR, 0.60; P=0.04) being significant risk factors for unhealed wounds after EVT. At 12 months, 34% had undergone reintervention (bypass surgery, 2.6%; repeat EVT, 31.7%), and 73% were major adverse event–free. Conclusions—The high reintervention rate notwithstanding, EVT was an effective treatment for Japanese critical limb ischemia patients with infrainguinal disease, with satisfactory AFS and major adverse limb event-free rates. The results of this study will be helpful for the future evaluation of critical limb ischemia therapy. Clinical Trial Registration—URL: http://www.umin.ac.jp/ctr. Unique identifier: UMIN000002830.


Journal of Trauma-injury Infection and Critical Care | 2012

Recombinant human soluble thrombomodulin improves mortality and respiratory dysfunction in patients with severe sepsis.

Yoshihito Ogawa; Kazuma Yamakawa; Hiroshi Ogura; Takeyuki Kiguchi; Tomoyoshi Mohri; Yasushi Nakamori; Yasuyuki Kuwagata; Takeshi Shimazu; Toshimitsu Hamasaki; Satoshi Fujimi

BACKGROUND: Respiratory dysfunction associated with severe sepsis is a serious condition leading to poor prognosis. Activation of coagulation is a consequence of and contributor to ongoing lung injury in severe sepsis. The purpose of this study was to examine the efficacy of recombinant human soluble thrombomodulin (rhTM), a novel anticoagulant agent, for treating patients with sepsis-induced disseminated intravascular coagulation (DIC) in terms of mortality and respiratory dysfunction. METHODS: This study comprised 86 consecutive patients with sepsis-induced DIC who required ventilator management. The initial 45 patients were treated without rhTM (control group), and the following 41 patients were given rhTM (0.06 mg/kg/d) for 6 days (rhTM group). Patients were followed up for 90 days after study entry. Sequential Organ Failure Assessment (SOFA) score and lung injury score were recorded until 7 days after entry. RESULTS: The baseline characteristic of severity of illness was significantly higher in the rhTM group than in the control group. Nevertheless, 90-day mortality rate in the rhTM group was significantly lower than that in the control group (37% vs. 58%, p = 0.038). There was a significant difference in the serial change of SOFA score from baseline to day 7 between the two groups (p = 0.009). Both the respiratory component of the SOFA score and the lung injury score in the rhTM group were significantly lower compared with the control group (p = 0.034 and p < 0.001, respectively). CONCLUSIONS: rhTM may have a significant beneficial effect on mortality and respiratory dysfunction in patients with sepsis-induced DIC. LEVEL OF EVIDENCE: III, therapeutic study.


Journal of Thrombosis and Haemostasis | 2015

Recombinant human soluble thrombomodulin in severe sepsis: a systematic review and meta‐analysis

Kazuma Yamakawa; M. Aihara; Hiroshi Ogura; Hiroki Yuhara; Toshimitsu Hamasaki; Takeshi Shimazu

Although recombinant human soluble thrombomodulin (rhTM) is a widely used novel anticoagulant agent for disseminated intravascular coagulation (DIC) in Japan, its clinical efficacy in sepsis‐induced DIC has not been demonstrated convincingly.


Neurology | 2005

Rapid disease progression correlates with instability of mutant SOD1 in familial ALS.

Takako Sato; Toyofumi Nakanishi; Yoichi Yamamoto; P. M. Andersen; Yoshihito Ogawa; Kei Fukada; Zhiwei Zhou; F. Aoike; Fuminobu Sugai; Seiichi Nagano; S. Hirata; M. Ogawa; R. Nakano; T. Ohi; T. Kato; M. Nakagawa; Toshimitsu Hamasaki; Akira Shimizu; Saburo Sakoda

Studies on the clinical course of familial ALS suggest that the duration of illness is relatively consistent for each mutation but variable among the different mutations. The authors analyzed the relative amount of mutant compared with normal SOD1 protein in the erythrocytes from 29 patients with ALS with 22 different mutations. Turnover of mutant SOD1 correlated with a shorter disease survival time.


Circulation | 2013

Cilostazol Reduces Angiographic Restenosis After Endovascular Therapy for Femoropopliteal Lesions in the Sufficient Treatment of Peripheral Intervention by Cilostazol Study

Osamu Iida; Hiroyoshi Yokoi; Yoshimitsu Soga; Naoto Inoue; Kenji Suzuki; Yoshiaki Yokoi; Daizo Kawasaki; Kan Zen; Kazushi Urasawa; Yoshiaki Shintani; Akira Miyamoto; Keisuke Hirano; Yusuke Miyashita; Taketsugu Tsuchiya; Norihiko Shinozaki; Masato Nakamura; Takaaki Isshiki; Toshimitsu Hamasaki; Shinsuke Nanto

Background— It remains unclear whether cilostazol, which has been shown to improve the clinical outcomes of endovascular therapy for femoropopliteal lesions, also reduces angiographic restenosis. Methods and Results— The Sufficient Treatment of Peripheral Intervention by Cilostazol (STOP-IC) study investigated whether cilostazol reduces the 12-month angiographic restenosis rate after percutaneous transluminal angioplasty with provisional nitinol stenting for femoropopliteal lesions. Two hundred patients with femoropopliteal lesions treated from March 2009 to April 2011 at 13 cardiovascular centers were randomly assigned 1:1 to receive oral aspirin with or without cilostazol. The primary end point was 12-month angiographic restenosis rate. Secondary end points were the restenosis rate on duplex ultrasound, the rate of major adverse cardiac events, and target lesion event-free survival. Researchers evaluated all follow-up data and assessed the end points in a blinded fashion. The mean lesion length and reference vessel diameter at the treated segment were 128±86 mm and 5.4±1.4 mm, respectively. The frequency of stent used was similar between groups (88% versus 90% in the cilostazol and noncilostazol group, respectively, P=0.82). During the 12-month follow-up period, 11 patients died and 152 patients (80%) had evaluable angiographic data at 12 months. The angiographic restenosis rate at 12 months was 20% (15/75) in the cilostazol group versus 49% (38/77) in the noncilostazol group (P=0.0001) by intention-to-treat analysis. The cilostazol group also had a significantly higher event-free survival at 12 months (83% versus 71%, P=0.02), although cardiovascular event rates were similar in both groups. Conclusions— Cilostazol reduced angiographic restenosis after percutaneous transluminal angioplasty with provisional nitinol stenting for femoropopliteal lesions. Clinical Trial Registration— URL: http://www.clinicaltrials.gov. Unique identifier: NCT00912756; and URL: https://www.umin.ac.jp. Unique identifier: UMIN000002091.

Collaboration


Dive into the Toshimitsu Hamasaki's collaboration.

Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar

Hiroshi Sato

Kwansei Gakuin University

View shared research outputs
Top Co-Authors

Avatar
Researchain Logo
Decentralizing Knowledge