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Dive into the research topics where Yuichi Fujii is active.

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Featured researches published by Yuichi Fujii.


Atherosclerosis | 2009

Oral infection-inflammatory pathway, periodontitis, is a risk factor for endothelial dysfunction in patients with coronary artery disease

Yukihito Higashi; Chikara Goto; Takayuki Hidaka; Junko Soga; Shuji Nakamura; Yuichi Fujii; Takaki Hata; Naomi Idei; Noritaka Fujimura; Kazuaki Chayama; Yasuki Kihara; Akira Taguchi

OBJECTIVE Several studies have shown that periodontitis is a risk factor for cardiovascular diseases. There is an association between inflammation and endothelial dysfunction. The purpose of this study was to evaluate endothelial function in patients with coronary artery disease (CAD) who had periodontitis. METHODS AND RESULTS We evaluated forearm blood flow (FBF) responses to acetylcholine (ACh), an endothelium-dependent vasodilator, and to sodium nitroprusside (SNP), an endothelium-independent vasodilator, in 101 CAD patients with periodontitis (37 men and 11 women, 63+/-12 yr) and without periodontitis (36 men and 17 women, 62+/-13 yr). FBF was measured by using strain-gauge plethysmography. Circulating levels of C-reactive protein and interleukin-6 were significantly higher in the periodontitis group than in the non-periodontitis group. FBF response to ACh was significantly smaller in the periodontitis group than in the non-periodontitis group. SNP-stimulated vasodilation was similar in the two groups. Periodontal therapy reduced serum concentrations of C-reactive protein from 2.7+/-1.9 to 1.8+/-0.9mg/L (P<0.05) and interleukin-6 from 2.6+/-3.4 to 1.6+/-2.6ng/L (P<0.05) and augmented ACh-induced vasodilation from 14.7+/-5.2 to 20.1+/-6.1mL/(min100mL) tissue (P<0.05) in patients with periodontitis. The SNP-stimulated vasodilation was similar before and after treatment. After administration of N(G)-monomethyl-l-arginine, a nitric oxide synthase inhibitor, FBF response to ACh was similar before and after treatment. CONCLUSION These findings suggest that periodontitis is associated with endothelial dysfunction in patients with CAD through a decrease in nitric oxide bioavailability. Systemic inflammation may be, at least in part, a cause and predictor of progression of endothelial dysfunction.


Circulation-cardiovascular Interventions | 2011

Autologous Bone-Marrow Mononuclear Cell Implantation Reduces Long-Term Major Amputation Risk in Patients With Critical Limb Ischemia A Comparison of Atherosclerotic Peripheral Arterial Disease and Buerger Disease

Naomi Idei; Junko Soga; Takaki Hata; Yuichi Fujii; Noritaka Fujimura; Shinsuke Mikami; Tatsuya Maruhashi; Kenji Nishioka; Takayuki Hidaka; Yasuki Kihara; Moniruddin Chowdhury; Kensuke Noma; Akira Taguchi; Kazuaki Chayama; Taijiro Sueda; Yukihito Higashi

Background— Bone-marrow mononuclear cell (BM-MNC) implantation improves ischemic symptoms in patients with critical limb ischemia (CLI). The purpose of this study was to evaluate long-term clinical outcomes after autologous BM-MNC implantation in patients with CLI. Methods and Results— We assessed long-term clinical outcomes after BM-MNC implantation in 51 patients with CLI, including 25 patients with peripheral arterial disease (PAD) and 26 patients with Buerger disease. Forty-six CLI patients who had no BM-MNC implantation served as control subjects. Median follow-up period was 4.8 years. The 4-year amputation-free rates after BM-MNC implantation were 48% in PAD patients and 95% in Buerger disease, and they were 0% in control PAD patients and 6% in control Buerger disease. The 4-year overall survival rates after BM-MNC implantation were 76% in PAD patients and 100% in Buerger disease, and they were 67% in control PAD patients and 100% in control Buerger disease. Multivariable Cox proportional hazards analysis revealed that BM-MNC implantation correlated with prevention of major amputation and that hemodialysis and diabetes mellitus correlated with major amputation. In Buerger disease, ankle brachial pressure index and transcutaneous oxygen pressure were significantly increased after 1 month and remained high during 3-year follow-up. However, in patients with PAD, ankle brachial pressure index and transcutaneous oxygen pressure significantly increased after 1 month and gradually decreased during 3-year follow-up and returned to baseline levels. Conclusions— These findings suggest that BM-MNC implantation is safe and effective in patients with CLI, especially in patients with Buerger disease. Clinical Trial Registration— URL: . Unique identifier: 001769.Background—Bone-marrow mononuclear cell (BM-MNC) implantation improves ischemic symptoms in patients with critical limb ischemia (CLI). The purpose of this study was to evaluate long-term clinical outcomes after autologous BM-MNC implantation in patients with CLI. Methods and Results—We assessed long-term clinical outcomes after BM-MNC implantation in 51 patients with CLI, including 25 patients with peripheral arterial disease (PAD) and 26 patients with Buerger disease. Forty-six CLI patients who had no BM-MNC implantation served as control subjects. Median follow-up period was 4.8 years. The 4-year amputation-free rates after BM-MNC implantation were 48% in PAD patients and 95% in Buerger disease, and they were 0% in control PAD patients and 6% in control Buerger disease. The 4-year overall survival rates after BM-MNC implantation were 76% in PAD patients and 100% in Buerger disease, and they were 67% in control PAD patients and 100% in control Buerger disease. Multivariable Cox proportional hazards analysis revealed that BM-MNC implantation correlated with prevention of major amputation and that hemodialysis and diabetes mellitus correlated with major amputation. In Buerger disease, ankle brachial pressure index and transcutaneous oxygen pressure were significantly increased after 1 month and remained high during 3-year follow-up. However, in patients with PAD, ankle brachial pressure index and transcutaneous oxygen pressure significantly increased after 1 month and gradually decreased during 3-year follow-up and returned to baseline levels. Conclusions—These findings suggest that BM-MNC implantation is safe and effective in patients with CLI, especially in patients with Buerger disease. Clinical Trial Registration—URL: http://home.hiroshima-u.ac.jp/angio/. Unique identifier: 001769.


Arteriosclerosis, Thrombosis, and Vascular Biology | 2011

Rho-Associated Kinase Activity, Endothelial Function, and Cardiovascular Risk Factors

Junko Soga; Kensuke Noma; Takaki Hata; Takayuki Hidaka; Yuichi Fujii; Naomi Idei; Noritaka Fujimura; Shinsuke Mikami; Tatsuya Maruhashi; Yasuki Kihara; Kazuaki Chayama; Hitoshi Kato; James K. Liao; Yukihito Higashi

Objective—Cardiovascular diseases are associated with chronic activation of Rho-associated kinases (ROCKs) and endothelial dysfunction. Both increased ROCK activity and endothelial dysfunction are thought to be closely associated with conventional cardiovascular risk factors. The purpose of this study was to determine the relationships between ROCK activity, endothelial function, and cardiovascular risk factors. Methods and Results—We evaluated ROCK activity in peripheral leukocytes by Western blot analysis and flow-mediated vasodilation by ultrasonography in 242 men who had no cardiovascular or cerebrovascular diseases (mean age, 40±10 years; range, 20 to 73 years). ROCK activity was defined as the ratio of phospho myosin-binding subunit on myosin light chain phosphatase to total myosin-binding subunit. Univariate regression analysis revealed that leukocyte ROCK activity significantly correlated with body mass index (r=0.29, P=0.003); systolic blood pressure (r=0.25, P=0.01); low-density lipoprotein cholesterol level (r=0.21, P=0.04); and Framingham risk factor score, a cumulative cardiovascular risk index for heart attack (r=0.31, P<0.001), and that flow-mediated vasodilation significantly correlated with age (r=−0.23, P=0.02), body mass index (r=0.19, P=0.05), systolic blood pressure (r=−0.22, P=0.03), total cholesterol level (r=−0.21, P=0.04), low-density lipoprotein cholesterol level (r=−0.22, P=0.04), glucose level (r=−0.20, P=0.04), and Framingham risk factor score (r=−0.37, P<0.001). There was a significant correlation between leukocyte ROCK activity and flow-mediated vasodilation (r=−0.41, P<0.001). Multivariate analysis revealed that flow-mediated vasodilation was an independent predictor of leukocyte ROCK activity. Conclusion—These findings suggest that cumulative cardiovascular risk may enhance ROCK activity and endothelial dysfunction, leading to progression of cardiovascular diseases and outcomes.


Clinical Pharmacology & Therapeutics | 2012

Mineralocorticoid Receptor Blocker Eplerenone Improves Endothelial Function and Inhibits Rho‐Associated Kinase Activity in Patients With Hypertension

Noritaka Fujimura; Kensuke Noma; Takaki Hata; Jyunko Soga; Toru Hidaka; Naomi Idei; Yuichi Fujii; Shinsuke Mikami; Tatsuya Maruhashi; Yumiko Iwamoto; Yasuki Kihara; Kazuaki Chayama; Hitoshi Kato; James K. Liao; Yukihito Higashi

Hypertension is associated with endothelial dysfunction and activated Rho‐associated kinases (ROCKs). The purpose of this study was to evaluate the effects of the selective mineralocorticoid receptor blocker, eplerenone, on endothelial function and ROCK activity in patients with hypertension. The study was carried out over 48 weeks in 60 untreated patients with hypertension who were randomly assigned to eplerenone, nifedipine, and losartan groups. We evaluated the effects of each treatment on flow‐mediated vasodilation (FMD) and ROCK activity in peripheral leukocytes. Eplerenone increased FMD and decreased leukocyte ROCK activity. Nifedipine decreased ROCK activity but did not alter FMD. Losartan increased FMD but did not alter ROCK activity. Hypotensive effects were similar in the three groups, as was nitroglycerin‐induced vasodilation during the follow‐up period. There were no significant differences between the groups with respect to other parameters. The study results show that eplerenone improves endothelial function and inhibits ROCK activity in patients with essential hypertension.


Circulation-cardiovascular Interventions | 2011

Autologous Bone-Marrow Mononuclear Cell Implantation Reduces Long-Term Major Amputation Risk in Patients With Critical Limb Ischemia

Naomi Idei; Junko Soga; Takaki Hata; Yuichi Fujii; Noritaka Fujimura; Shinsuke Mikami; Tatsuya Maruhashi; Kenji Nishioka; Takayuki Hidaka; Yasuki Kihara; Moniruddin Chowdhury; Kensuke Noma; Akira Taguchi; Kazuaki Chayama; Taijiro Sueda; Yukihito Higashi

Background— Bone-marrow mononuclear cell (BM-MNC) implantation improves ischemic symptoms in patients with critical limb ischemia (CLI). The purpose of this study was to evaluate long-term clinical outcomes after autologous BM-MNC implantation in patients with CLI. Methods and Results— We assessed long-term clinical outcomes after BM-MNC implantation in 51 patients with CLI, including 25 patients with peripheral arterial disease (PAD) and 26 patients with Buerger disease. Forty-six CLI patients who had no BM-MNC implantation served as control subjects. Median follow-up period was 4.8 years. The 4-year amputation-free rates after BM-MNC implantation were 48% in PAD patients and 95% in Buerger disease, and they were 0% in control PAD patients and 6% in control Buerger disease. The 4-year overall survival rates after BM-MNC implantation were 76% in PAD patients and 100% in Buerger disease, and they were 67% in control PAD patients and 100% in control Buerger disease. Multivariable Cox proportional hazards analysis revealed that BM-MNC implantation correlated with prevention of major amputation and that hemodialysis and diabetes mellitus correlated with major amputation. In Buerger disease, ankle brachial pressure index and transcutaneous oxygen pressure were significantly increased after 1 month and remained high during 3-year follow-up. However, in patients with PAD, ankle brachial pressure index and transcutaneous oxygen pressure significantly increased after 1 month and gradually decreased during 3-year follow-up and returned to baseline levels. Conclusions— These findings suggest that BM-MNC implantation is safe and effective in patients with CLI, especially in patients with Buerger disease. Clinical Trial Registration— URL: . Unique identifier: 001769.Background—Bone-marrow mononuclear cell (BM-MNC) implantation improves ischemic symptoms in patients with critical limb ischemia (CLI). The purpose of this study was to evaluate long-term clinical outcomes after autologous BM-MNC implantation in patients with CLI. Methods and Results—We assessed long-term clinical outcomes after BM-MNC implantation in 51 patients with CLI, including 25 patients with peripheral arterial disease (PAD) and 26 patients with Buerger disease. Forty-six CLI patients who had no BM-MNC implantation served as control subjects. Median follow-up period was 4.8 years. The 4-year amputation-free rates after BM-MNC implantation were 48% in PAD patients and 95% in Buerger disease, and they were 0% in control PAD patients and 6% in control Buerger disease. The 4-year overall survival rates after BM-MNC implantation were 76% in PAD patients and 100% in Buerger disease, and they were 67% in control PAD patients and 100% in control Buerger disease. Multivariable Cox proportional hazards analysis revealed that BM-MNC implantation correlated with prevention of major amputation and that hemodialysis and diabetes mellitus correlated with major amputation. In Buerger disease, ankle brachial pressure index and transcutaneous oxygen pressure were significantly increased after 1 month and remained high during 3-year follow-up. However, in patients with PAD, ankle brachial pressure index and transcutaneous oxygen pressure significantly increased after 1 month and gradually decreased during 3-year follow-up and returned to baseline levels. Conclusions—These findings suggest that BM-MNC implantation is safe and effective in patients with CLI, especially in patients with Buerger disease. Clinical Trial Registration—URL: http://home.hiroshima-u.ac.jp/angio/. Unique identifier: 001769.


Journal of Hypertension | 2011

Calcium Channel Blocker and Rho-associated Kinase Activity in Patients with Hypertension

Takaki Hata; Junko Soga; Takayuki Hidaka; Naomi Idei; Yuichi Fujii; Noritaka Fujimura; Shinsuke Mikami; Tatsuya Maruhashi; Yasuki Kihara; Kazuaki Chayama; Hitoshi Kato; Kensuke Noma; James K. Liao; Yukihito Higashi

Background Rho-associated kinases (ROCKs) play an important role in Ca2+ sensitization and vascular resistance. Activation of ROCKs is associated with hypertension. The purpose of this study was to evaluate the effect of the calcium channel blocker amlodipine on ROCKs activity in patients with hypertension. Methods We evaluated ROCK activity in peripheral leukocytes by Western blot analysis in 651 patients with hypertension treated with antihypertensive agents, 28 untreated hypertensive patients and 28 healthy individuals, and the effects of treatment with amlodipine or losartan for 12 weeks on ROCK activity in 28 untreated hypertensive patients who were randomly divided into an amlodipine group (n = 14) and a losartan group (n = 14). ROCK activity was defined as the ratio of phospho myosin-binding subunit (MBS) on myosin light-chain phosphatase to total MBS. Results Leukocyte ROCK activity was greater in untreated patients with essential hypertension than in the healthy individuals (0.84 ± 0.24 vs. 0.61 ± 0.18, P = 0.03). In 651 patients with hypertension treated with antihypertensive agents, ROCK activity was significantly lower in the calcium channel blocker-treated group than in the groups treated with renin–angiotensin system inhibitors, diuretics, and β-blockers (0.70 ± 0.24 vs. 0.85 ± 0.29, 0.83 ± 0.24, and 0.86 ± 0.31, P < 0.05, respectively). ROCK activity after 4 and 12 weeks of treatment was significantly decreased in the amlodipine group (0 weeks: 0.85 ± 0.25, 4 weeks: 0.66 ± 0.16, 12 weeks: 0.64 ± 0.15, P < 0.05, respectively) but not in the losartan group, whereas the antihypertensive effects were similar in the two groups. Conclusion These findings suggest that calcium channel blocker amlodipine inhibits ROCK activity in patients with hypertension.


American Journal of Physiology-endocrinology and Metabolism | 2010

Endothelial function in subjects with isolated low HDL cholesterol: role of nitric oxide and circulating progenitor cells

Yukihito Higashi; Hidehiro Matsuoka; Hidekazu Umei; Ryo Sugano; Yuichi Fujii; Junko Soga; Yasuki Kihara; Kazuaki Chayama; Tsutomu Imaizumi

Epidemiologic studies have shown that a low level of high-density lipoprotein (HDL) cholesterol is a risk factor for cardiovascular diseases. The purpose of this study was to determine the contribution of isolated low HDL cholesterol to endothelial function. Thirty-nine subjects with low HDL cholesterol who had no other cardiovascular risk factors were selected from the 5,417 participants from our population. We evaluated flow-mediated vasodilation (FMD) before and after 4 wk of treatment with the HMG-CoA reductase inhibitor pravastatin in 29 of the 39 subjects with isolated low HDL cholesterol. FMD was lower in the low-HDL-cholesterol group (n = 29) than in the control group (n = 29), whereas NTG-induced vasodilation was similar in the two groups. Pravastatin increased HDL cholesterol, urinary excretion of nitrite/nitrate, circulating levels of progenitor cells, and cell migration response to vascular endothelial growth factor in 15 subjects with low HDL cholesterol but not in 14 placebo control subjects. FMD increased in the pravastatin treatment group but not in the control group. NTG-induced vasodilation was similar before and after 4 wk of treatment in the two groups. Multiple regression analysis revealed that changes in HDL cholesterol, the number of progenitor cells, and migration of progenitor cells were independent predictors of augmentation of FMD with pravastatin. These findings suggest that low HDL cholesterol is an independent risk factor for endothelial dysfunction and that pravastatin improves endothelial function in individuals with isolated low HDL cholesterol through, at least in part, an increase in circulating progenitor cells.


Arteriosclerosis, Thrombosis, and Vascular Biology | 2012

Intima-Media Thickness of Brachial Artery, Vascular Function, and Cardiovascular Risk Factors

Yumiko Iwamoto; Tatsuya Maruhashi; Yuichi Fujii; Naomi Idei; Noritaka Fujimura; Shinsuke Mikami; Masato Kajikawa; Takeshi Matsumoto; Yasuki Kihara; Kazuaki Chayama; Kensuke Noma; Ayumu Nakashima; Yukihito Higashi

Objective—Cardiovascular diseases are associated with impaired flow-mediated vasodilation (FMD) and increase in carotid intima-media thickness (IMT). Both FMD and IMT are independent predictors for cardiovascular outcomes. When measuring FMD and nitroglycerine-induced vasodilation in the brachial artery, IMT can also be simultaneously assessed in the same brachial artery. The purpose of this study was to determine the relationships between IMT of the brachial artery, vascular function, and cardiovascular risk factors. Methods and Results—We measured brachial IMT, FMD, and nitroglycerine-induced vasodilation by ultrasound in 388 subjects who underwent health examination (mean age, 45±22 years; age range, 19–86), including patients with cardiovascular diseases. Univariate regression analysis revealed that brachial IMT significantly correlated with age (r=0.71; P<0.001), body mass index (r=0.27; P<0.001), systolic blood pressure (r=0.40; P<0.001), diastolic blood pressure (r=0.31; P<0.001), heart rate (r=0.15; P=0.002), glucose level (r=0.18; P=0.01), and smoking pack-years (r=0.42; P<0.001), as well as Framingham risk score, a cumulative cardiovascular risk index for heart attack (r=0.49; P<0.001). FMD and nitroglycerine-induced vasodilation were inversely associated with brachial IMT (r=−0.39, P<0.001; r=−0.32, P<0.001, respectively). In addition, there was a significant relationship between brachial IMT and carotid IMT (r=0.58; P<0.001). Multivariate analysis revealed that age, sex, hypertension, and brachial artery diameter were independent predictors of brachial IMT. Conclusion—These findings suggest that brachial IMT may be a marker of the grade of atherosclerosis and may be used as a marker of vascular function, providing additive information for stratifying subjects with cardiovascular risk factors.


Hypertension Research | 2010

Increased leukocyte rho kinase (ROCK) activity and endothelial dysfunction in cigarette smokers

Takayuki Hidaka; Takaki Hata; Junko Soga; Yuichi Fujii; Naomi Idei; Noritaka Fujimura; Yasuki Kihara; Kensuke Noma; James K. Liao; Yukihito Higashi

Rho-associated kinases (ROCKs) have been shown to be involved in the pathogenesis of atherosclerosis. Although smoking is associated with endothelial dysfunction and ROCK inhibitors improve endothelial function in smokers, it is not known whether ROCK activity is increased in smokers and whether this correlates with endothelial dysfunction. The purpose of this study was to evaluate the relationship between ROCK activity and endothelial function in smokers. We evaluated flow-mediated vasodilatation (FMD) using ultrasonography and ROCK activity in peripheral leukocytes using western blot analysis in 14 male smokers (28.1±3.9 years) and 15 healthy male non-smokers (28.3±3.6 years). ROCK activity was defined as the ratio of phospho-myosin-binding subunit (MBS) on myosin light-chain phosphatase to total MBS. FMD was significantly less in smokers than in non-smokers (4.7±3.1 vs. 9.0±3.8%, P=0.005). Nitroglycerine-induced vasodilation was similar in the two groups. ROCK activity was greater in smokers than in non-smokers (0.78±0.27 vs. 0.54±018, P=0.012). The expression of total MBS, ROCK1 and ROCK2 were similar in the two groups. ROCK activity correlated with systolic blood pressure (r=0.42, P=0.039). Multiple regression analysis revealed that smoking is an independent predictor of ROCK activity. There was a significant correlation between FMD and ROCK activity (r=−0.42, P=0.035). No other variable was correlated with FMD. These findings suggest that ROCK activity is enhanced by smoking and is a predictor of endothelial function.


Hypertension | 2011

Vascular Function and Circulating Progenitor Cells in Thromboangitis Obliterans (Buerger's Disease) and Atherosclerosis Obliterans

Naomi Idei; Kenji Nishioka; Junko Soga; Takayuki Hidaka; Takaki Hata; Yuichi Fujii; Noritaka Fujimura; Tatsuya Maruhashi; Shinsuke Mikami; Hiroki Teragawa; Yasuki Kihara; Kensuke Noma; Kazuaki Chayama; Yukihito Higashi

Thromboangitis obliterans (TAO; Buergers disease) and atherosclerosis obliterans (ASO) are associated with endothelial dysfunction. The purpose of this study was to evaluate the role of circulating progenitor cells (CPCs) in endothelial function in patients with TAO and ASO. We measured flow-mediated vasodilation (FMD), nitroglycerine-induced vasodilation, and circulating CPCs in 30 patients with TAO and 30 age- and sex-matched healthy subjects and in 40 patients with ASO. FMD was smaller in both the TAO group and ASO group than in the control group (6.6±2.7%, 5.7±3.3% versus 9.5±3.1%, P<0.0001, respectively). There was no significant difference in FMD between the TAO group and ASO group. Nitroglycerine-induced vasodilation was similar in the 3 groups. The number of and migration of circulating CPCs were similar in the TAO group and control group, whereas the number of and migration of circulating CPCs were significantly lower in the ASO group than in other groups (ASO 553±297/mL versus TAO 963±543/mL; control 1063±426/mL and ASO 36±18/hpf versus TAO 62±23/hpf; control 68±18/hpf, P<0.0001, respectively). There was a significant relationship between the number of and migration of CPCs and FMD (r=0.43 and r=0.40, P<0.0001, respectively). FMD was impaired in patients with TAO as well as in patients with ASO compared to that in normal control subjects, and the number of and function of circulating CPCs were not decreased in patients with TAO. These findings may partially explain why there are differences in cardiovascular morbidity and mortality rates between patients with TAO and patients with ASO.

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