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Dive into the research topics where Kazuhiko Nishigaki is active.

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Featured researches published by Kazuhiko Nishigaki.


Journal of the American College of Cardiology | 1997

Plasma Fas Ligand, an Inducer of Apoptosis, and Plasma Soluble Fas, an Inhibitor of Apoptosis, in Patients With Chronic Congestive Heart Failure

Kazuhiko Nishigaki; Shinya Minatoguchi; Mitsuru Seishima; Kiyoji Asano; Toshiyuki Noda; Norio Yasuda; Hirotake Sano; Hirokazu Kumada; Masao Takemura; Akio Noma; Tsutomu Tanaka; Sachiro Watanabe; Hisayoshi Fujiwara

OBJECTIVES This study sought to examine plasma levels of soluble Fas/APO-1 receptor (sFas), an inhibitor of apoptosis, and soluble Fas ligand (sFas-L), an inducer of apoptosis, and their relation to each other and to other clinical variables, such as New York Heart Association functional class, tumor necrosis factor (TNF) and interleukin-6 (IL-6) in congestive heart failure (CHF). BACKGROUND It has been recently reported that apoptotic cell death occurs in myocytes of dogs with CHF. Hypoxia is frequently seen in advanced CHF and can stimulate Fas/APO-1 receptors (Fas) to induce apoptosis in cultured myocytes. Fas and Fas ligand (Fas-L) are cell-surface proteins and representative apoptosis-signaling molecules. Fas on the cell membrane induces apoptosis when it binds Fas-L or sFas-L. However, plasma sFas, a molecule lacking the transmembrane domain of Fas, blocks apoptosis by inhibiting binding between Fas and Fas-L or sFas-L on the cell membrane. At present, it is unknown whether plasma sFas-L and plasma sFas increase in the presence of cardiac disease. METHODS The study included 70 patients (mean [+/-SEM] age 65 +/- 2 years, range 21 to 93) with chronic CHF (coronary artery disease in 28, dilated cardiomyopathy in 27, valvular heart disease in 15) and 62 age- and gender-matched normal control subjects. Plasma levels of sFas, sFas-L, TNF-alpha and IL-6 were measured by enzyme-linked immunosorbent assays using monoclonal anti-human antibodies. RESULTS There was no significant difference in sFas-L levels between normal subjects and patients in functional classes I to IV; however, sFas increased with severity of functional classification, independent of the underlying disease. sFas levels were significantly higher even in patients in functional class II than in normal subjects and those in functional class I, and were highest in patients in functional class IV (normal subjects; 2.2 +/- 0.1 ng/ml; functional class I: 2.2 +/- 0.2 ng/ml; functional class II: 3.1 +/- 0.2 ng/ml; functional class III: 3.9 +/- 0.3 ng/ml; functional class IV: 5.1 +/- 0.6 ng/ml). Plasma sFas levels were significantly higher in patients with elevated pulmonary artery wedge pressure and a decresed cardiac index than in those with values in the normal range. In patients in functional class IV, there was no significant difference in plasma sFas levels between the survivors and non-survivors during 6-month follow-up. However, plasma levels of sFas tended to decrease in nine patients with clinical improvement (baseline sFas: 5.2 +/- 0.8 ng/ml; 6-month sFas: 4.3 +/- 0.5 ng/ml, p = 0.07) but were similar in patients with no change in functional class. TNF-alpha and IL-6 were increased significantly only in patients in functional class IV, as previously reported, but were not related to sFas. CONCLUSIONS We found elevated levels of plasma sFas and no increase in plasma sFas-L in human CHF. The increase in sFas may play an important role in the pathophysiologic mechanisms of CHF.


Journal of the American College of Cardiology | 2001

Noninvasive quantitative tissue characterization and two-dimensional color-coded map of human atherosclerotic lesions using ultrasound Integrated backscatter comparison between histology and Integrated backscatter images

Masanori Kawasaki; Hisato Takatsu; Toshiyuki Noda; Yoko Ito; Akihisa Kunishima; Masazumi Arai; Kazuhiko Nishigaki; Genzou Takemura; Norihiko Morita; Shinya Minatoguchi; Hisayoshi Fujiwara

OBJECTIVES The purpose of the present study was to define clinicopathologically whether integrated backscatter (IB) combined with conventional two-dimensional echo (2DE) can differentiate the tissue characteristics of calcification (CL), fibrosis (FI), lipid pool (LP) with fibrous cap, intimal hyperplasia (IH) and thrombus (TH) and can construct two-dimensional tissue plaque structure in vivo. BACKGROUND It is difficult to characterize the components of plaque using conventional 2DE techniques. METHODS Integrated backscatter values of plaques were measured in the right common carotid and femoral arteries (total 24 segments) both during life and after autopsy in 12 patients (age 68 to 84 years, 10 men and two women). Integrated backscatter values were determined using a 5-12 MHz multifrequency transducer, setting the region of interests (ROIs) (11 x 11 pixels) on the echo tomography of the entire arterial wall (55 +/- 10 ROI/segment) and comparing it with histologic features in the autopsied arterial specimens. RESULTS Corrected IB values obtained before death and at autopsy were significantly correlated (r = 0.93, p < 0.01). Corresponding to the histologic features, corrected IB values on the rectangle ROIs obtained during life were divided into five categories: category 1 (TH) 4 < IB < or = 6; category 2 (media and IH or LP in the intima) 7 < IB < or = 13; category 3 (FI) 13 < IB < or = 18, category 4 (mixed lesion) 18 < IB < or = 27 and category 5 (CL) 28 < IB < or = 33. In category 2, media and intima were differentiated using conventional 2DE. Under the above procedures, color-coded maps constructed with IB-2DE obtained during life precisely reflected the histologic features of media and intima. CONCLUSIONS Integrated backscatter with 2DE represents a useful noninvasive tool for evaluating the tissue structure of human plaque.


Circulation | 2000

Considerable Time From the Onset of Plaque Rupture and/or Thrombi Until the Onset of Acute Myocardial Infarction in Humans Coronary Angiographic Findings Within 1 Week Before the Onset of Infarction

Shinsuke Ojio; Hisato Takatsu; Tsutomu Tanaka; Katsumi Ueno; Koichi Yokoya; Tetsuo Matsubara; Takahiko Suzuki; Sachiro Watanabe; Norihiko Morita; Masanori Kawasaki; Toshihiko Nagano; Itsuki Nishio; Kazuyoshi Sakai; Kazuhiko Nishigaki; Genzou Takemura; Toshiyuki Noda; Shinya Minatoguchi; Hisayoshi Fujiwara

BackgroundIt has been thought that the thrombi and bleeding in plaques that occur after plaque rupture or endothelial damage from vessels with mild stenosis suddenly occlude the lumen and cause acute myocardial infarction (AMI). However, our hypothesis is that thrombi and bleeding may not suddenly occlude the lumen. Methods and ResultsThe study group consisted of 20 patients who had coronary angiograms performed within 1 week (3±3 days) before AMI and 20 control patients who had coronary angiograms performed 6 to 18 months (282±49 days) before AMI. The features of infarct-related coronary segments (IRCS) at 3 days before AMI were the presence of a significant stenosis of >50% (95% in incidence and 71±12% diameter stenosis) and Ambrose’s type II eccentric lesions (plus multiple irregularities), an indicator of plaque rupture and/or thrombi (60% [70%]), and the features at 1 year before AMI were mild stenosis of <50% (95% incidence and 30±18% diameter stenosis) with rare Ambrose’s type II eccentric lesions (plus multiple irregularities) (10% [10%]). The same relation was observed in each of the 4 subgroups with Q-wave infarction, non–Q-wave infarction, preceding effort angina within 1 month before AMI, and no preceding effort angina. ConclusionsThe appearance of marked progression and Ambrose’s type II eccentric lesion on coronary angiograms 3 days before AMI suggests the presence of a considerable time from the onset of plaque rupture and/or thrombi until the onset of AMI. These features may be predictors of AMI. The concept provides new insight into the mechanism and prevention of human AMIs.


Circulation | 1999

Process of progression of coronary artery lesions from mild or moderate stenosis to moderate or severe stenosis: A study based on four serial coronary arteriograms per year.

Koichi Yokoya; Hisato Takatsu; Takahiko Suzuki; Hiroaki Hosokawa; Shinsuke Ojio; Tetsuo Matsubara; Tsutomu Tanaka; Sachiro Watanabe; Norihiko Morita; Kazuhiko Nishigaki; Genzou Takemura; Toshiyuki Noda; Shinya Minatoguchi; Hisayoshi Fujiwara

BACKGROUND The process of progression in coronary artery disease is unknown. METHODS AND RESULTS The subjects were 36 patients with 36 objective vessels with clinically significant progression of coronary artery disease (>/=15% per year) in whom 4 serial coronary arteriograms (CAGs) were performed at intervals of approximately 4 months in a 1-year period. The degree of progression of percent stenosis between each of 2 serial CAGs was classified as marked (M: >/=15%), slight (S: 5% to 14%), and no progression (N: <5%). From the pattern of progression, the 36 vessels were classified as 14 type 1 vessels with marked progression (N-->N-->M in 13 vessels and S-->S-->M in 1 vessel) and 22 type 2 vessels without marked progression (S-->S-->S in 18 vessels, N-->S-->S in 4). Percent stenosis at the first, second, third, and final CAGs was 44+/-14%, 46+/-13%, 46+/-13%, and 88+/-10% (P<0.05 versus first CAG) in type 1 vessels and 44+/-11%, 50+/-9%, 59+/-9%, and 67+/-9% in type 2 vessels (P<0.05 for second, third, and final CAGs versus first CAG). Type 1 vessels featured the sudden appearance of severe stenosis due to marked progression, angina pectoris, or myocardial infarction (71%) and Ambrose type II eccentric lesions indicating plaque rupture or thrombi (57%). Type 2 vessels featured continuous slight progression of stenosis with smooth vessel walls; angina pectoris (14%) occurred when the percent stenosis reached a severe level. An increase in serum C-reactive protein was observed only in the type 2 vessel group, which suggests a relation between continuous slight progression and inflammatory change. CONCLUSIONS Two types of stenosis progression provide a new insight into the mechanism of coronary artery disease.


Journal of the American College of Cardiology | 2000

Three minute, but not one minute, ischemia and nicorandil have a preconditioning effect in patients with coronary artery disease.

Tetsuo Matsubara; Shinya Minatoguchi; Hitoshi Matsuo; Kenji Hayakawa; Tomonori Segawa; Yukihiko Matsuno; Sachiro Watanabe; Masazumi Arai; Yoshihiro Uno; Masanori Kawasaki; Toshiyuki Noda; Genzou Takemura; Kazuhiko Nishigaki; Hisayoshi Fujiwara

OBJECTIVES This study focused on 1) the determination of the optimal preconditioning (PC) duration, and 2) the protective effect of nicorandil (NC), a hybrid nitrate with a KATP channel opening effect, during a percutaneous transluminal coronary angioplasty (PTCA) model in humans. BACKGROUND The ischemic PC effect is induced in 180 s ischemia, but not in 120 s ischemia in rabbit hearts. However, the duration of ischemia that induces PC effect and the role of the KATP channel in the PC effect in humans are still unclear. METHODS Forty-six patients with stable angina were randomly allocated to four groups: the duration of the first inflation as PC ischemia was 60 s in the PC60 group (n = 12), and 180 s in the PC180 group (n = 12). In the other groups, NC (80 microg/kg) was intravenously given for 1 min in the NC group (n = 12), and isosorbide dinitrate (ISDN) (40 microg/kg) was given in the ISDN group (n = 10). Five minutes after first inflation or drug administration, a second inflation was conducted for 120 s in each group. In the ECG, the lead with the largest shift in ST segment (deltaST max), and the sum of elevated ST levels in all leads (sigmaST) were determined. RESULTS In the PC60 group, no significant difference was observed in either deltaST max or sigmaST between the first and second inflation. However, the second inflation in the PC180 group showed significantly lower levels of deltaST max and sigmaST compared with those of the first inflation. In the NC group, both deltaST max and sigmaST measured at 30 s and 60 s after balloon inflation were significantly lower than those of the first inflation in the PC60 and PC180 control groups. In the ISDN group, no significant difference was observed in deltaST max or sigmaST. CONCLUSION In human PTCA models, a PC effect is observed in 180 s ischemia, but not in 60 s ischemia. A pharmacological PC effect is induced by NC, a KATP channel opener with a nitrate-like effect but not ISDN. This suggests that the opening of KATP channels plays an important role in the protecting effect of NC.


Circulation | 2006

Granulocyte Colony-Stimulating Factor

Masazumi Arai; Yu Misao; Hiroshi Nagai; Masanori Kawasaki; Kenshi Nagashima; Koji Suzuki; Kunihiko Tsuchiya; Setsuko Otsuka; Yoshihiro Uno; Genzou Takemura; Kazuhiko Nishigaki; Shinya Minatoguchi; Hisayoshi Fujiwara

Background The purpose of this study was to determine whether treatment with granulocyte colony-stimulating factor (G-CSF), which mobilizes endothelial progenitor cells from bone marrow, can safely improve the clinical outcomes of patients with atherosclerotic peripheral artery disease (PAD). Methods and Results Thirty-nine patients with intractable PAD were randomly assigned to 3 groups: a negative control group (n=12) treated with conventional drug therapy; a positive control group (n=13) treated with conventional drug therapy plus bone marrow transplantation (BMT); and a G-CSF group (n=14) treated with conventional therapy plus subcutaneous injection of 2-5 μg/kg of recombinant human G-CSF once daily for 10 days. One month after treatment, subjective symptoms improved significantly in the G-CSF and BMT groups. Ankle-brachial pressure index and transcutaneous oxygen pressure increased significantly in the BMT and G-CSF groups, but no such improvements were seen in the group receiving conventional therapy alone. Conclusions G-CSF improves the clinical signs and symptoms of patients with intractable PAD to the same degree as BMT does. This noninvasive treatment may thus represent a useful new approach to managing the disease. (Circ J 2006; 70: 1093 - 1098)


Respiratory Medicine | 1998

An increase of soluble Fas, an inhibitor of apoptosis, associated with progression of COPD

Norio Yasuda; Kohshi Gotoh; Shinya Minatoguchi; Kiyoji Asano; Kazuhiko Nishigaki; M. Nomura; A. Ohno; M. Watanabe; Hirotake Sano; Hirokazu Kumada; T. Sawa; Hisayoshi Fujiwara

In chronic obstructive pulmonary disease (COPD) which consists of emphysema and chronic bronchitis, alveolar tissue and/or bronchiolar walls are progressively destroyed. This suggests cell death by necrosis and/or apoptosis although no direct evidence of apoptosis has been reported. It was speculated that the apoptosis-related factors are associated with the progression of COPD. Fas/Apo-1 receptor (Fas), Fas ligand (Fas-L) and soluble Fas ligand (sFas-L) are inducers, while soluble Fas (sFas) is an inhibitor of apoptosis. In this study, plasma sFas and sFas-L were measured in 19 COPD patients receiving supplemental O2 (severe COPD) and 20 COPD patients not receiving supplemental O2 (mild/moderate COPD). Twenty-two age- and sex-matched healthy volunteers (healthy controls) and 20 patients receiving supplemental O2 and with level of hypoxaemia similar to severe COPD due to other pulmonary diseases (disease controls) were also examined. Plasma sFas-L was within normal limits in all groups. Plasma sFas levels were similar among healthy controls, disease controls, and mild/moderate COPD patients, but significantly increased in severe COPD (2.6 +/- 1.1, 2.6 +/- 0.2, 2.8 +/- 0.2 and 4.8 +/- 1.0 ng ml-1, respectively). Although PaO2 was lower in severe COPD than in mild/moderate COPD, and PaCO2 was higher in severe COPD than in mild/moderate COPD, they were close between severe COPD and disease controls. Tumour necrosis factor-alpha (TNF-alpha), interleukin 6 (IL-6) and C-reactive protein (CRP) were increased in patients with COPD, but were similar in both severe and mild/moderate COPD patients. We conclude that increased plasma sFas, which is independent of hypoxaemia, and increases in PaCO2, TNF-alpha, IL-6 and inflammation, may be associated with progression of COPD.


Journal of the American College of Cardiology | 1996

Marked expression of plasma brain natriuretic peptide is a special feature of hypertrophic obstructive cardiomyopathy

Kazuhiko Nishigaki; Masaaki Tomita; Kensaku Kagawa; Toshiyuki Noda; Shinya Minatoguchi; Hiroshi Oda; Sachiro Watanabe; Norihiko Morita; Kazuwa Nakao; Hisayoshi Fujiwara

OBJECTIVES We examined whether plasma brain natriuretic peptide levels are abnormally elevated in hypertrophic obstructive cardiomyopathy compared with other cardiac diseases. BACKGROUND We previously reported that plasma brain and atrial natriuretic peptide levels were elevated in hypertrophic cardiomyopathy. METHODS We compared plasma concentrations of brain and atrial natriuretic peptide and hemodynamic and echocardiographic data in 50 patients with hypertrophic obstructive cardiomyopathy (n = 15, mean [+/-SD] intraventricular pressure gradient 37 +/- 16 mm Hg), hypertrophic nonobstructive cardiomyopathy (n = 15), aortic stenosis (n = 10, mean pressure gradient 41 +/- 18 mm Hg) and hypertensive heart disease (n = 10, mean systolic/diastolic blood pressure 203 +/- 16/108 +/- 11 mm Hg, respectively) and 10 normal subjects. RESULTS Plasma brain natriuretic peptide levels were higher in the hypertrophic obstructive cardiomyopathy group (397.1 +/- 167.8 pg/ml*) than in the hypertrophic nonobstructive cardiomyopathy (60.0 +/- 48.1 pg/ml*), hypertensive heart disease (53.9 +/- 31.4 pg/ml*), aortic stenosis (75.4 +/- 54.3 pg/ml*) and normal groups (9.8 +/- 6.4 pg/ml [*p < 0.05 vs. normal group, p < 0.05 vs. hypertrophic obstructive cardiomyopathy group]). Although plasma atrial natriuretic peptide levels were higher in the hypertrophic obstructive cardiomyopathy group than the other patient groups, the brain/atrial natriuretic peptide ratio in the hypertrophic obstructive cardiomyopathy group was higher (4.5 +/- 2.3) than those in the other three patient groups (1.1 to 1.4) and the normal group (0.7 +/- 0.5). Left ventricular end-diastolic pressure and left ventricular end-diastolic volume index were similar among the four patient groups. The interventricular septal thickness and the ratio of interventricular septal thickness to left ventricular posterior wall thickness were similar between the hypertrophic obstructive and nonobstructive cardiomyopathy groups. CONCLUSIONS Abnormal elevations of plasma brain natriuretic peptide levels are difficult to explain on the basis of hemodynamic and echocardiographic data and are a special feature of hypertrophic obstructive cardiomyopathy.


Jacc-cardiovascular Interventions | 2008

Percutaneous coronary intervention plus medical therapy reduces the incidence of acute coronary syndrome more effectively than initial medical therapy only among patients with low-risk coronary artery disease a randomized, comparative, multicenter study.

Kazuhiko Nishigaki; Tsutomu Yamazaki; Akira Kitabatake; Tetsu Yamaguchi; Katsuo Kanmatsuse; Itsuo Kodama; Noboru Takekoshi; Hitonobu Tomoike; Masatsugu Hori; Masunori Matsuzaki; Akira Takeshita; Takuro Shimbo; Hisayoshi Fujiwara; Jsap Study Investigators

OBJECTIVES This study sought to determine whether initial medical therapy (MT) only or percutaneous coronary intervention plus medical therapy (PCI+MT) is better for patients with low-risk stable coronary artery disease (CAD) indicated for intervention in Japan. BACKGROUND Several multicenter studies have suggested that in the above patients, an initial management strategy of PCI+MT does not reduce the long-term risk of cardiovascular events more effectively than initial MT only. METHODS We conducted a randomized comparative study (JSAP [Japanese Stable Angina Pectoris] study) in the previously mentioned patients. RESULTS The patients were randomized to PCI+MT (n = 192) or initial MT only group (n = 192), and the patient characteristics were very similar in the 2 groups. During the 3.3-year follow-up, there was no significant difference in the cumulative death rate between PCI+MT (2.9%) and MT (3.9%). However, the cumulative risk of death plus acute coronary syndrome was significantly smaller in PCI+MT. CONCLUSIONS In stable low-risk CAD, PCI+MT may improve long-term prognosis more effectively than MT.


Cardiovascular Research | 2008

Post-infarct treatment with an erythropoietin-gelatin hydrogel drug delivery system for cardiac repair.

Hiroyuki Kobayashi; Shinya Minatoguchi; Shinji Yasuda; Narentuoya Bao; Itta Kawamura; Masamitsu Iwasa; Takahiko Yamaki; Syohei Sumi; Yu Misao; Kazuhiko Nishigaki; Genzou Takemura; Takako Fujiwara; Yasuhiko Tabata; Hisayoshi Fujiwara

AIMS We investigated the effect of an erythropoietin (EPO)-gelatin hydrogel drug delivery system (DDS) applied to the heart on myocardial infarct (MI) size, left ventricular (LV) remodelling and function. METHODS AND RESULTS Experiments were performed in a rabbit model of MI. The infarct size was reduced, and LV remodelling and function were improved 14 days and 2 months after MI but not at 2 days after MI in the EPO-DDS group. The number of cluster of differentiation 31(CD31)-positive microvessels and the expression of erythropoietin receptor (EPO-R), phosphorylated-Akt (p-Akt), phosphorylated glycogen synthase kinase 3beta (p-GSK-3beta), phosphorylated extracellular signal-regulated protein kinase (p-ERK), phosphorylated signal transducer and activator of transcription 3 (p-Stat3), vascular endothelial growth factor (VEGF), and matrix metalloproteinase-1 (MMP-1) were significantly increased in the myocardium of the EPO-DDS group. CONCLUSION Post-MI treatment with an EPO-DDS improves LV remodelling and function by activating prosurvival signalling, antifibrosis, and angiogenesis without causing any side effect.

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