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Dive into the research topics where Michihiro Okuyama is active.

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Featured researches published by Michihiro Okuyama.


Circulation Research | 2015

Intracoronary Autologous Cardiac Progenitor Cell Transfer in Patients With Hypoplastic Left Heart Syndrome The TICAP Prospective Phase 1 Controlled Trial

Shuta Ishigami; Shinichi Ohtsuki; Suguru Tarui; Daiki Ousaka; Takahiro Eitoku; Maiko Kondo; Michihiro Okuyama; Junko Kobayashi; Kenji Baba; Sadahiko Arai; Takuya Kawabata; Ko Yoshizumi; Atsushi Tateishi; Yosuke Kuroko; Tatsuo Iwasaki; Shuhei Sato; Shingo Kasahara; Shunji Sano; Hidemasa Oh

Rationale: Hypoplastic left heart syndrome (HLHS) remains a lethal congenital cardiac defect. Recent studies have suggested that intracoronary administration of autologous cardiosphere-derived cells (CDCs) may improve ventricular function. Objective: The aim of this study was to test whether intracoronary delivery of CDCs is feasible and safe in patients with hypoplastic left heart syndrome. Methods and Results: Between January 5, 2011, and January 16, 2012, 14 patients (1.8±1.5 years) were prospectively assigned to receive intracoronary infusion of autologous CDCs 33.4±8.1 days after staged procedures (n=7), followed by 7 controls with standard palliation alone. The primary end point was to assess the safety, and the secondary end point included the preliminary efficacy to verify the right ventricular ejection fraction improvements between baseline and 3 months. Manufacturing and intracoronary delivery of CDCs were feasible, and no serious adverse events were reported within the 18-month follow-up. Patients treated with CDCs showed right ventricular ejection fraction improvement from baseline to 3-month follow-up (46.9%±4.6% to 52.1%±2.4%; P=0.008). Compared with controls at 18 months, cardiac MRI analysis of CDC-treated patients showed a higher right ventricular ejection fraction (31.5%±6.8% versus 40.4%±7.6%; P=0.049), improved somatic growth (P=0.0005), reduced heart failure status (P=0.003), and lower incidence of coil occlusion for collaterals (P=0.007). Conclusions: Intracoronary infusion of autologous CDCs seems to be feasible and safe in children with hypoplastic left heart syndrome after staged surgery. Large phase 2 trials are warranted to examine the potential effects of cardiac function improvements and the long-term benefits of clinical outcomes. Clinical Trial Registration: URL: http://www.clinicaltrials.gov. Unique identifier: NCT01273857.


BioMed Research International | 2015

Novel Model of Pulmonary Artery Banding Leading to Right Heart Failure in Rats

Masataka Hirata; Daiki Ousaka; Sadahiko Arai; Michihiro Okuyama; Suguru Tarui; Junko Kobayashi; Shingo Kasahara; Shunji Sano

Background. Congenital heart diseases often involve chronic pressure overload of the right ventricle (RV) which is a major cause of RV dysfunction. Pulmonary artery (PA) banding has been used to produce animal models of RV dysfunction. We have devised a new and easier method of constricting the PA and compared it directly with the partial ligation method. Methods. Eight-week-old male Sprague-Dawley rats (240–260 g) were divided into three groups: sham operation, partial pulmonary artery ligation (PAL) procedure, and pulmonary artery half-closed clip (PAC) procedure. RV function and remodeling were determined by echocardiography and histomorphometry. Results. Surgical mortality was significantly lower in the PAC group while echocardiography revealed significantly more signs of RV dysfunction. At the 8th week after surgery RV fibrosis rate was significantly higher in the PAC group. Conclusions. This procedure of pulmonary artery banding in rats is easier and more efficient than partial ligation.


Circulation Research | 2015

Intracoronary Autologous Cardiac Progenitor Cell Transfer in Patients With Hypoplastic Left Heart Syndrome

Shuta Ishigami; Shinichi Ohtsuki; Suguru Tarui; Daiki Ousaka; Takahiro Eitoku; Maiko Kondo; Michihiro Okuyama; Junko Kobayashi; Kenji Baba; Sadahiko Arai; Takuya Kawabata; Ko Yoshizumi; Atsushi Tateishi; Yosuke Kuroko; Tatsuo Iwasaki; Shuhei Sato; Shingo Kasahara; Shunji Sano; Hidemasa Oh

Rationale: Hypoplastic left heart syndrome (HLHS) remains a lethal congenital cardiac defect. Recent studies have suggested that intracoronary administration of autologous cardiosphere-derived cells (CDCs) may improve ventricular function. Objective: The aim of this study was to test whether intracoronary delivery of CDCs is feasible and safe in patients with hypoplastic left heart syndrome. Methods and Results: Between January 5, 2011, and January 16, 2012, 14 patients (1.8±1.5 years) were prospectively assigned to receive intracoronary infusion of autologous CDCs 33.4±8.1 days after staged procedures (n=7), followed by 7 controls with standard palliation alone. The primary end point was to assess the safety, and the secondary end point included the preliminary efficacy to verify the right ventricular ejection fraction improvements between baseline and 3 months. Manufacturing and intracoronary delivery of CDCs were feasible, and no serious adverse events were reported within the 18-month follow-up. Patients treated with CDCs showed right ventricular ejection fraction improvement from baseline to 3-month follow-up (46.9%±4.6% to 52.1%±2.4%; P=0.008). Compared with controls at 18 months, cardiac MRI analysis of CDC-treated patients showed a higher right ventricular ejection fraction (31.5%±6.8% versus 40.4%±7.6%; P=0.049), improved somatic growth (P=0.0005), reduced heart failure status (P=0.003), and lower incidence of coil occlusion for collaterals (P=0.007). Conclusions: Intracoronary infusion of autologous CDCs seems to be feasible and safe in children with hypoplastic left heart syndrome after staged surgery. Large phase 2 trials are warranted to examine the potential effects of cardiac function improvements and the long-term benefits of clinical outcomes. Clinical Trial Registration: URL: http://www.clinicaltrials.gov. Unique identifier: NCT01273857.


Vascular | 2018

Peripheral artery disease is associated with frailty in chronic hemodialysis patients

Michihiro Okuyama; Hidemi Takeuchi; Haruhito A. Uchida; Yuki Kakio; Yuka Okuyama; Ryoko Umebayashi; Kentaro Wada; Hitoshi Sugiyama; Ken Sugimoto; Hiromi Rakugi; Shingo Kasahara; Jun Wada

Objectives The clinical condition of frailty is a common problem in the elderly population. However, the relationship between peripheral artery disease and frailty in hemodialysis patients remains unknown. The aim of this study was to identify the relationships between peripheral artery disease and frailty in Japanese chronic hemodialysis patients. Methods A total of 362 chronic hemodialysis patients who regularly visited six institutions were enrolled. To evaluate frailty, the modified Fried’s frailty phenotype adjusted for Japanese were used. Peripheral artery disease was defined as ankle-brachial index <0.9. Results Of 362 patients, 62 patients (17.1%) were categorized as peripheral artery disease group and 300 patients (82.9%) as Non-peripheral artery disease group. The prevalence of frailty in the peripheral artery disease group was significantly higher than in the Non-peripheral artery disease group (34% vs. 18%, P = 0.0103). Non-shunt side grip strength was significantly stronger in the Non-peripheral artery disease group (23.6 kg vs. 17.0 kg, P < 0.0001). Thigh circumferences were also significantly larger in the Non-peripheral artery disease group (41.7 cm vs. 39.7 cm, P = 0.0054). A multivariate logistic regression analysis demonstrated that the factors independently associated with peripheral artery disease were as follows: frailty (odds ratio = 2.06, 95% confidence interval 1.09–3.89) and myocardial infarction (odds ratio = 3.74, 95% confidence interval 2.05–6.83). Conclusions It is concluded that peripheral artery disease is closely associated with frailty in hemodialysis patients.


Aging and Disease | 2018

The prevalence of frailty and its associated factors in Japanese hemodialysis patients

Hidemi Takeuchi; Haruhito A. Uchida; Yuki Kakio; Yuka Okuyama; Michihiro Okuyama; Ryoko Umebayashi; Kentaro Wada; Hitoshi Sugiyama; Ken Sugimoto; Hiromi Rakugi; Jun Wada

The population undergoing dialysis is aging worldwide, particularly in Japan. The clinical condition of frailty is the most problematic expression in the elderly population. Potential pathophysiological factors of frailty present in patients with CKD and are accentuated in patients with ESRD. The aim of this study was to identify the prevalence and predictors of frailty in Japanese HD patients. This study was a multicenter, cross-sectional and observational investigation conducted at 6 institutions. To evaluate frailty, the modified Fried’s frailty phenotype adjusted for Japanese as the self-reported questionnaire was used. Of the 542 patients visiting each institution, 388 were enrolled in this study. In total, 26.0% of participants were categorized as not-frailty, 52.6% as pre-frailty and 21.4% as frailty. The prevalence of frailty increased steadily with age and was more prevalent in females than in males and the subjects with frailty received polypharmacy. A multivariate logistic regression analysis revealed that the factors independently associated with frailty were the following: female gender (odds ratio [OR] = 3.661, 95% confidence interval [CI] 1.398-9.588), age (OR = 1.065, 95% CI 1.014-1.119), age ≥ 75 years old (OR = 4.892, 95% CI 1.715-13.955), body mass index (BMI) < 18.5 (OR = 0.110, 95% CI 0.0293-0.416), number of medications being taken (OR = 1.351, 95% CI 1.163-1.570), diabetes mellitus (DM) (OR = 2.765, 95% CI 1.081-7.071) and MNA-SF ≤ 11 (OR = 7.405, 95% CI 2.732-20.072). Frailty was associated with the accumulation of risk factors. The prevalence of frailty in Japanese patients with HD was relatively lower than that previously reported in Western developed countries; however, it was extremely high compared to the general population regardless of age. Our findings suggest that frailty might be associated with an increase in the prevalence of adverse health outcomes in patients with HD.


PLOS ONE | 2016

Chronic Kidney Disease Is Positively and Diabetes Mellitus Is Negatively Associated with Abdominal Aortic Aneurysm.

Hidemi Takeuchi; Michihiro Okuyama; Haruhito A. Uchida; Yuki Kakio; Ryoko Umebayashi; Yuka Okuyama; Yasuhiro Fujii; Susumu Ozawa; Masashi Yoshida; Yu Oshima; Shunji Sano; Jun Wada

Background and Aims Chronic kidney disease (CKD) and diabetes mellitus (DM) are considered as risk factors for cardiovascular diseases. The purpose of this study was to clarify the relationship of CKD and DM with the presence of abdominal aortic aneurysm (AAA). Methods We enrolled 261 patients with AAA (AAA+) and age-and-sex matched 261 patients without AAA (AAA-) at two hospitals between 2008 and 2014, and examined the association between the risk factors and the presence of AAA. Furthermore, in order to investigate the prevalence of AAA in each group, we enrolled 1126 patients with CKD and 400 patients with DM. Results The presence of CKD in patients with AAA+ was significantly higher than that in patients with AAA- (AAA+; 65%, AAA-; 52%, P = 0.004). The presence of DM in patients with AAA+ was significantly lower than that in patients with AAA- (AAA+; 17%, AAA-; 35%, P < 0.001). A multivariate logistic regression analysis demonstrated that hypertension, ischemic heart disease and CKD were independent determinants, whereas, DM was a negatively independent determinant, for the presence of AAA. The prevalence of AAA in patients with CKD 65 years old and above was 5.1%, whereas, that in patients with DM 65 years old and above was only 0.6%. Conclusion CKD is a positively associated with the presence of AAA. In contrast, DM is a negatively associated with the presence of AAA in Japanese population.


Geriatrics & Gerontology International | 2018

Diabetic nephropathy is associated with frailty in patients with chronic hemodialysis: Frailty status of HD patients with DN

Yuki Kakio; Haruhito A. Uchida; Hidemi Takeuchi; Yuka Okuyama; Michihiro Okuyama; Ryoko Umebayashi; Kentaro Wada; Hitoshi Sugiyama; Ken Sugimoto; Hiromi Rakugi; Shingo Kasahara; Jun Wada

Since 1998, the leading cause of chronic hemodialysis in Japan has been diabetic nephropathy. Diabetes mellitus is known to be a risk factor for frailty, but it still remains unknown whether diabetic nephropathy is associated with frailty in chronic dialysis patients. The authors carried out the present study to reveal the association between frailty and diabetic nephropathy in chronic hemodialysis patients.


Circulation Research | 2015

Intracoronary Autologous Cardiac Progenitor Cell Transfer in Patients With Hypoplastic Left Heart SyndromeNovelty and Significance

Shuta Ishigami; Shinichi Ohtsuki; Suguru Tarui; Daiki Ousaka; Takahiro Eitoku; Maiko Kondo; Michihiro Okuyama; Junko Kobayashi; Kenji Baba; Sadahiko Arai; Takuya Kawabata; Ko Yoshizumi; Atsushi Tateishi; Yosuke Kuroko; Tatsuo Iwasaki; Shuhei Sato; Shingo Kasahara; Shunji Sano; Hidemasa Oh

Rationale: Hypoplastic left heart syndrome (HLHS) remains a lethal congenital cardiac defect. Recent studies have suggested that intracoronary administration of autologous cardiosphere-derived cells (CDCs) may improve ventricular function. Objective: The aim of this study was to test whether intracoronary delivery of CDCs is feasible and safe in patients with hypoplastic left heart syndrome. Methods and Results: Between January 5, 2011, and January 16, 2012, 14 patients (1.8±1.5 years) were prospectively assigned to receive intracoronary infusion of autologous CDCs 33.4±8.1 days after staged procedures (n=7), followed by 7 controls with standard palliation alone. The primary end point was to assess the safety, and the secondary end point included the preliminary efficacy to verify the right ventricular ejection fraction improvements between baseline and 3 months. Manufacturing and intracoronary delivery of CDCs were feasible, and no serious adverse events were reported within the 18-month follow-up. Patients treated with CDCs showed right ventricular ejection fraction improvement from baseline to 3-month follow-up (46.9%±4.6% to 52.1%±2.4%; P=0.008). Compared with controls at 18 months, cardiac MRI analysis of CDC-treated patients showed a higher right ventricular ejection fraction (31.5%±6.8% versus 40.4%±7.6%; P=0.049), improved somatic growth (P=0.0005), reduced heart failure status (P=0.003), and lower incidence of coil occlusion for collaterals (P=0.007). Conclusions: Intracoronary infusion of autologous CDCs seems to be feasible and safe in children with hypoplastic left heart syndrome after staged surgery. Large phase 2 trials are warranted to examine the potential effects of cardiac function improvements and the long-term benefits of clinical outcomes. Clinical Trial Registration: URL: http://www.clinicaltrials.gov. Unique identifier: NCT01273857.


Circulation Research | 2015

Intracoronary Autologous Cardiac Progenitor Cell Transfer in Patients With Hypoplastic Left Heart SyndromeNovelty and Significance: The TICAP Prospective Phase 1 Controlled Trial

Shuta Ishigami; Shinichi Ohtsuki; Suguru Tarui; Daiki Ousaka; Takahiro Eitoku; Maiko Kondo; Michihiro Okuyama; Junko Kobayashi; Kenji Baba; Sadahiko Arai; Takuya Kawabata; Ko Yoshizumi; Atsushi Tateishi; Yosuke Kuroko; Tatsuo Iwasaki; Shuhei Sato; Shingo Kasahara; Shunji Sano; Hidemasa Oh

Rationale: Hypoplastic left heart syndrome (HLHS) remains a lethal congenital cardiac defect. Recent studies have suggested that intracoronary administration of autologous cardiosphere-derived cells (CDCs) may improve ventricular function. Objective: The aim of this study was to test whether intracoronary delivery of CDCs is feasible and safe in patients with hypoplastic left heart syndrome. Methods and Results: Between January 5, 2011, and January 16, 2012, 14 patients (1.8±1.5 years) were prospectively assigned to receive intracoronary infusion of autologous CDCs 33.4±8.1 days after staged procedures (n=7), followed by 7 controls with standard palliation alone. The primary end point was to assess the safety, and the secondary end point included the preliminary efficacy to verify the right ventricular ejection fraction improvements between baseline and 3 months. Manufacturing and intracoronary delivery of CDCs were feasible, and no serious adverse events were reported within the 18-month follow-up. Patients treated with CDCs showed right ventricular ejection fraction improvement from baseline to 3-month follow-up (46.9%±4.6% to 52.1%±2.4%; P=0.008). Compared with controls at 18 months, cardiac MRI analysis of CDC-treated patients showed a higher right ventricular ejection fraction (31.5%±6.8% versus 40.4%±7.6%; P=0.049), improved somatic growth (P=0.0005), reduced heart failure status (P=0.003), and lower incidence of coil occlusion for collaterals (P=0.007). Conclusions: Intracoronary infusion of autologous CDCs seems to be feasible and safe in children with hypoplastic left heart syndrome after staged surgery. Large phase 2 trials are warranted to examine the potential effects of cardiac function improvements and the long-term benefits of clinical outcomes. Clinical Trial Registration: URL: http://www.clinicaltrials.gov. Unique identifier: NCT01273857.


Arteriosclerosis, Thrombosis, and Vascular Biology | 2016

Abstract 305: Exogenous Vasohibin-2 Exacerbates Angiotensin II-induced Ascending Aortic Aneurysms

Michihiro Okuyama; Haruhito A. Uchida; Ryoko Umebayashi; Yuki Kakio; Katsuyuki Tanabe; Yasufumi Sato; Jun Wada

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