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Dive into the research topics where Norio Tanahashi is active.

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Featured researches published by Norio Tanahashi.


Lancet Neurology | 2010

Cilostazol for prevention of secondary stroke (CSPS 2): an aspirin-controlled, double-blind, randomised non-inferiority trial

Yukito Shinohara; Yasuo Katayama; Shinichiro Uchiyama; Takenori Yamaguchi; Shunnosuke Handa; Kempei Matsuoka; Yasuo Ohashi; Norio Tanahashi; Hiroko Yamamoto; Chokoh Genka; Yasuhisa Kitagawa; Hideo Kusuoka; Katsuya Nishimaru; Motoo Tsushima; Yukihiro Koretsune; Tohru Sawada; Chikuma Hamada

BACKGROUND The antiplatelet drug cilostazol is efficacious for prevention of stroke recurrence compared with placebo. We designed the second Cilostazol Stroke Prevention Study (CSPS 2) to establish non-inferiority of cilostazol versus aspirin for prevention of stroke, and to compare the efficacy and safety of cilostazol and aspirin in patients with non-cardioembolic ischaemic stroke. METHODS Patients aged 20-79 years who had had a cerebral infarction within the previous 26 weeks were enrolled at 278 sites in Japan and allocated to receive 100 mg cilostazol twice daily or 81 mg aspirin once daily for 1-5 years. Patients were allocated according to a computer-generated randomisation sequence by means of a dynamic balancing method using patient information obtained at registration. All patients, study personnel, investigators, and the sponsor were masked to treatment allocation. The primary endpoint was the first occurrence of stroke (cerebral infarction, cerebral haemorrhage, or subarachnoid haemorrhage). The predefined margin of non-inferiority was an upper 95% CI limit for the hazard ratio of 1·33. Analyses were by full-analysis set. This trial is registered with ClinicalTrials.gov, number NCT00234065. FINDINGS Between December, 2003, and October, 2006, 2757 patients were enrolled and randomly allocated to receive cilostazol (n=1379) or aspirin (n=1378), of whom 1337 on cilostazol and 1335 on aspirin were included in analyses; mean follow-up was 29 months (SD 16). The primary endpoint occurred at yearly rates of 2·76% (n=82) in the cilostazol group and 3·71% (n=119) in the aspirin group (hazard ratio 0·743, 95% CI 0·564-0·981; p=0·0357). Haemorrhagic events (cerebral haemorrhage, subarachnoid haemorrhage, or haemorrhage requiring hospital admission) occurred in fewer patients on cilostazol (0·77%, n=23) than on aspirin (1·78%, n=57; 0·458, 0·296-0·711; p=0·0004), but headache, diarrhoea, palpitation, dizziness, and tachycardia were more frequent in the cilostazol group than in the aspirin group. INTERPRETATION Cilostazol seems to be non-inferior, and might be superior, to aspirin for prevention of stroke after an ischaemic stroke, and was associated with fewer haemorrhagic events. Therefore, cilostazol could be used for prevention of stroke in patients with non-cardioembolic stroke. FUNDING Otsuka Pharmaceutical.


Stroke | 2010

Thrombolysis With 0.6 mg/kg Intravenous Alteplase for Acute Ischemic Stroke in Routine Clinical Practice The Japan post-Marketing Alteplase Registration Study (J-MARS)

Jyoji Nakagawara; Kazuo Minematsu; Yasushi Okada; Norio Tanahashi; Shinji Nagahiro; Etsuro Mori; Yukito Shinohara; Takenori Yamaguchi; for J-Mars Investigators

Background and Purpose— In Japan, alteplase at 0.6 mg/kg was approved in October 2005 for use within 3 hours of stroke onset by the Ministry of Health, Labor and Welfare (MHLW). The aim of the Japan post-Marketing Alteplase Registration Study (J-MARS), which was requested by MHLW at the time of approval, was to assess the safety and efficacy of 0.6 mg/kg alteplase in routine clinical practice for the Japanese. Methods— A total of 7492 patients from 942 centers were enrolled in the J-MARS, an open-label, nonrandomized, observational study, from October 2005 to October 2007. Primary outcome measures were symptomatic intracranial hemorrhage (a deterioration in NIHSS score ≥4 from baseline) and favorable outcome (modified Rankin Scale score, 0–1) at 3 months after stroke onset. Results— The proportion of patients with symptomatic intracranial hemorrhage in 7492 patients (safety analysis) was 3.5% (95% confidence interval [CI], 3.1%–3.9%) within 36 hours and 4.4% (95% CI, 3.9%–4.9%) at 3 months. The overall mortality rate was 13.1% (95% CI, 12.4%–13.9%) and the proportion of patients with fatal symptomatic intracranial hemorrhage was 0.9% (95% CI, 0.7%–1.2%). The outcomes at 3 months were available for 4944 patients and the proportion of favorable outcome (efficacy analysis) was 33.1% (95% CI, 31.8%–34.4%). The subgroup analysis in patients between 18 and 80 years with a baseline NIHSS score <25 demonstrated that favorable outcome at 3 months was 39.0% (95% CI, 37.4%–40.6%). Conclusions— These data suggest that 0.6 mg/kg intravenous alteplase within 3 hours of stroke onset could be safe and effective in routine clinical practice for the Japanese.


Stroke | 1997

Prognostic Value of Admission Blood Pressure in Patients With Intracerebral Hemorrhage Keio Cooperative Stroke Study

Yasuo Terayama; Norio Tanahashi; Yasuo Fukuuchi; Fumio Gotoh

BACKGROUND AND PURPOSE Patients with acute stroke on admission to the hospital are often found to have high blood pressure. The purpose of the present study was to investigate the prognostic value of admission blood pressure in patients with acute intracerebral hemorrhage, including putaminal, thalamic, subcortical, cerebellar, and pontine hemorrhage. METHODS A total of 1701 patients with intracerebral hemorrhage of the putamen (n = 776; mean +/- SD age, 58 +/- 14 years) thalamus (n = 538; 63 +/- 12 years), subcortex (n = 153; 61 +/- 16 years), cerebellum (n = 110; 64 +/- 11 years), and pons (n = 124; 59 +/- 13 years) were examined. The mean blood pressure on admission in patients with a fatal outcome was compared with that in patients who survived. RESULTS The mean age in each patient group (putaminal, thalamic, subcortical, cerebellar, and pontine hemorrhage) with fatal outcome was older than that with nonfatal outcome, while ANCOVA indicated no correlation between age and blood pressure on admission or age and volume of hematoma. The mean arterial blood pressure on hospital admission was 126.9 +/- 25.8 mm Hg (+/-SD) in cases of putaminal. 127.4 +/- 22.6 mm Hg in thalamic, 116.4 +/- 20.6 mm Hg in subcortical, 123.5 +/- 23.9 mm Hg in cerebellar, and 133.0 +/- 26.0 mm Hg in pontine hemorrhage. The mean blood pressure on admission in patients with a fatal outcome among those with putaminal (136.0 +/- 36.3 mm Hg) and thalamic (133.2 +/- 22.1 mm Hg) hemorrhage was significantly higher than that in those with a nonfatal outcome (123.8 +/- 20.6 mm Hg for putaminal, 101.6 +/- 22.5 mm Hg for thalamic) (P < .01). No correlation between mean blood pressure and outcome was observed in the patients with subcortical (116.5 +/- 22.2 mm Hg for nonfatal, 114.9 +/- 22.0 mm Hg for fatal outcome), cerebellar (125.2 +/- 22.2 mm Hg, 116.9 +/- 28.8 mm Hg), and pontine (129.9 +/- 23.8 mm Hg, 136.0 +/- 27.7 mm Hg) hemorrhage. The volume of hematoma on admission in patients with fatal outcome with putaminal (58.2 +/- 24.4 mL), thalamic (27.0 +/- 13.1 mL), subcortical (32.9 +/- 14.4 mL), and cerebellar (31.4 +/- 28.6 mL) hemorrhage was greater than that in those with nonfatal outcome (20.8 +/- 11.4 mL, 7.1 +/- 4.8 mL, 18.3 +/- 10.6 mL, and 8.1 +/- 4.2 mL, respectively; P < .01), while no correlation between volume of hematoma and outcome was observed in patients with pontine hemorrhage. CONCLUSIONS The above data suggest that an increased mean blood pressure and volume of hematoma on admission in putaminal and thalamic hemorrhage were related to increased mortality, while in patients with subcortical, cerebellar, and pontine hemorrhage, the mean blood pressure was not related to the clinical outcome.


Stroke | 2000

C242T Polymorphism of NADPH Oxidase p22 PHOX Gene and Ischemic Cerebrovascular Disease in the Japanese Population

Daisuke Ito; Mitsuru Murata; Kiyoaki Watanabe; Tadashi Yoshida; Ikuo Saito; Norio Tanahashi; Yasuo Fukuuchi

BACKGROUND AND PURPOSE Superoxide has been implicated in the pathogenesis of ischemic stroke and atherosclerosis. NADPH oxidase, a major source of superoxide generation in neutrophils and the vascular system, plays a critical role in ischemic injury and atherogenesis. Recently, an association between the C242T polymorphism of p22 PHOX, an essential component of NADPH oxidase, and coronary artery disease (CAD) has been reported in several studies. To investigate the relationship between the C242T polymorphism of p22 PHOX and ischemic cerebrovascular disease (CVD), we conducted a case-control study. METHODS We recruited 226 CVD patients (atherothrombotic infarction, lacunar infarction, and transient ischemic attack) and 301 control subjects and analyzed C242T polymorphism of p22 PHOX by detection of restriction fragment length polymorphism. RESULTS The TC+TT genotype frequencies in the CVD group and control group were 21.7% and 13.3%, respectively, and the prevalence of the TC+TT genotype was significantly higher in the CVD patients (chi(2)=6.477, P=0.01, OR 1.81, 95% CI 1.15 to 2.86). Analysis by CVD subtypes showed that the OR for the TC+TT genotype was higher in the CVD patients with atherothrombotic infarction than in those with lacunar infarction and transient ischemic attack. CONCLUSIONS The C242T polymorphism of the NADPH oxidase p22 PHOX gene is a novel pathogenetic risk factor for CVD.


Stroke | 2000

Polymorphism in the promoter of lipopolysaccharide receptor CD14 and ischemic cerebrovascular disease

Daisuke Ito; Mitsuru Murata; Norio Tanahashi; Hideki Sato; Akira Sonoda; Ikuo Saito; Kiyoaki Watanabe; Yasuo Fukuuchi

Background and Purpose A growing amount of evidence suggests that infectious and inflammatory processes may be involved in the initiation of arteriosclerosis, but the mechanisms are conceivably multifactorial and complex. Two European groups have recently demonstrated that a C(−260)→T polymorphism in the promoter of the CD14 lipopolysaccharide receptor may be a risk factor for coronary artery disease (CAD). The T allele of this polymorphism reportedly increases the expression of CD14 and may be involved in atherogenesis. In the present study we investigated a possible association between the C(−260)→T polymorphism in the CD14 promoter and the occurrence of symptomatic ischemic cerebrovascular disease (CVD). Methods Genotype frequencies of the C(−260)→T polymorphism in the CD14 promoter were determined in 235 patients with CVD, as confirmed by brain CT and/or MRI, and 309 age- and sex-matched control subjects. Results The distribution of genotypes was as follows: CVD patients, T/ T 24.3%, C/ T 53.2%, and C/ C 22.6%; controls, T/ T 26.9%, C/ T 50.2%, and C/ C 23.0%. There was no significant difference between the CD14 promoter genotypes of the CVD patients and the controls (&khgr;2=0.601, P =0.741). We also measured the concentration of serum soluble CD14 and the density of membranous CD14 on monocytes in the CVD patients, but the polymorphism was not associated with either the concentration of soluble CD14 or the density of membranous CD14 (P =0.358, P =0.238, respectively). Conclusions Our results indicate that the C(−260)→T polymorphism in the CD14 promoter is not associated with an increased risk for CVD.


Stroke | 2000

Association Between Platelet Glycoprotein Ibα Genotype and Ischemic Cerebrovascular Disease

Akira Sonoda; Mitsuru Murata; Daisuke Ito; Norio Tanahashi; Atsumi Ohta; Yoko Tada; Eiko Takeshita; Tadashi Yoshida; Ikuo Saito; Masatoshi Yamamoto; Yasuo Ikeda; Yasuo Fukuuchi; Kiyoaki Watanabe

BACKGROUND AND PURPOSE Platelets play pivotal roles in the development of ischemic cerebrovascular disease (CVD). The platelet glycoprotein (GP) Ib/IX/V complex is a receptor for von Willebrand factor, which plays a major role in the initial phase of platelet activation under high shear stress conditions. This study was designed to investigate the association between a genetic variation of this receptor and the prevalence of CVD. METHODS Two hundred patients with ischemic CVD, as confirmed by brain CT and/or MRI, and 317 age- and sex-matched control subjects without clinical evidence of CVD or cardiovascular disease were analyzed for their genotype frequencies of the (145)Thr/Met dimorphism of the alpha-chain of GPIb (GPIbalpha). RESULTS Genotypes with (145)Met (T/M and M/M) were more frequently found in the CVD patients (26.5%) than in control subjects (14.2%, P=0.0005). The genotype effect was more obvious in those <60 years of age or without acquired cardiovascular risk factors. The odds ratio for nonsmoking women <60 years of age was 10. 6 (95% confidence intervals, 2.2 to 51.7). Although the number of patients studied was small (n=24), transient ischemic attack showed the highest odds ratio (4.3, P=0.0004), followed by lacunar infarction (OR=2.2, P=0.0024) and atherothrombotic infarction (OR=1. 5, P=0.3143). Logistic regression analysis revealed that the presence of Met-allele was independently associated with CVD. CONCLUSIONS Our study suggests that the platelet GPIbalpha genotype is a genetic risk factor for ischemic CVD.


Journal of Stroke & Cerebrovascular Diseases | 2013

Guidelines for the intravenous application of recombinant tissue-type plasminogen activator (alteplase), the second edition, October 2012: a guideline from the Japan Stroke Society.

Kazuo Minematsu; Kazunori Toyoda; Teruyuki Hirano; Kazumi Kimura; Rei Kondo; Etsuro Mori; Jyoji Nakagawara; Nobuyuki Sakai; Yoshiaki Shiokawa; Norio Tanahashi; Masahiro Yasaka; Yasuo Katayama; Susumu Miyamoto; Akira Ogawa; Makoto Sasaki; Sadao Suga; Takenori Yamaguchi

In Japan, intravenous alteplase, a recombinant tissue-type plasminogen activator (rt-PA), was approved for an indication of ischemic stroke in 2005 on the basis of the results of a clinical trial with a unique dose of the drug (0.6 mg/kg). The Japan Stroke Society published the guidelines for intravenous application of rt-PA and organized training sessions for proper use all over Japan in an effort to promote the safe, widespread use of intravenous alteplase. Seven years following its approval, clinical experience with intravenous alteplase has accumulated, additional evidence of intravenous alteplase has been found in Japan and overseas, and the medical environment has substantially changed, including approvals for new drugs and medical devices. Notably, the use of alteplase in the extended therapeutic time window (within 4.5 hours of symptom onset) became covered by insurance in Japan in August 2012. To address these changing situations, we have decided to prepare the revised guidelines. In preparing the second edition, we took care to make its contents more practical by emphasizing information needed in clinical practice. While the first edition was developed with emphasis on safety in light of limited clinical experience with intravenous alteplase in Japan in 2005, this second edition is a substantial revision of the first edition mainly in terms of eligibility criteria, on the basis of accumulated evidence and the clinical experience.


Journal of Cerebral Blood Flow and Metabolism | 2004

Fluorometric determination of glucose utilization in neurons in vitro and in vivo

Yoshiaki Itoh; Takato Abe; Rie Takaoka; Norio Tanahashi

Glucose is the major energy source the adult brain utilizes under physiologic conditions. Recent findings, however, have suggested that neurons obtain most of their energy from the oxidation of extracellular lactate derived from astroglial metabolism of glucose transported into the brain from the blood. In the present studies we have used 2-[N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl)amino]-2-deoxy-D-glucose (2-NBDG), a fluorescent analogue of 2-deoxyglucose, which is often used to trace glucose utilization in neural tissues, to examine glucose metabolism in neurons in vitro and in vivo. Cultured neurons and astroglia were incubated with 2-NBDG for up to 15 minutes, and nonmetabolized 2-NBDG was washed out. We found that fluorescence intensity increased linearly with incubation time in both neurons and astroglia, indicating that both types of brain cells could utilize glucose as their energy source in vitro. To determine if the same were true in vivo, Sprague-Dawley rats were injected intravenously with a pulse bolus of 2-NBDG and decapitated 45 minutes later. Examination of brain sections demonstrated that phosphorylated 2-NBDG accumulated in hippocampal neurons and cerebellar Purkinje cells, indicating that neurons can utilize glucose in vivo as energy source.


Brain Research | 1994

Role of nitric oxide in regulation of cerebral microvascular tone and autoregulation of cerebral blood flow in cats.

Masahiro Kobari; Yasuo Fukuuchi; Minoru Tomita; Norio Tanahashi; Hidetaka Takeda

The role of nitric oxide in the regulation of cerebrocortical microvascular tone and autoregulation of cerebral blood flow (CBF) was examined in 24 anesthetized cats. The local cerebral blood volume (CBV), mean transit time of blood (MTT), and CBF in the cortex were measured by our photoelectric method. CBV represents the cumulative dimensions of the cerebral microvessels. Intravenous injection of 0.35-0.7 mg/kg/min NG-monomethyl-L-arginine (L-NMMA), an inhibitor of nitric oxide synthesis, significantly increased mean arterial blood pressure (MABP; 8.4-14.1%, P < 0.01), decreased CBV (15.2-28.7%, P < 0.01), and decreased CBF (20.0-29.8%, P < 0.01) in a dose-related manner. The changes in MABP, CBV, and CBF elicited by L-NMMA were inhibited (P < 0.05) by simultaneous infusion of 35 mg/kg/min L-arginine. Autoregulation of CBF was examined during controlled hypotension of -30 to -40 mmHg (artificial bleeding) and recovery of blood pressure (reinfusion of blood). Although CBF remained constant with blood pressure changes in the control state (delta CBF/delta MABP of 0.037 +/- 0.155 with hypotension), CBF became dependent on blood pressure changes (delta CBF/delta MABP of 0.478 +/- 0.135, P < 0.05) during infusion of 0.35 mg/kg/min L-NMMA. It is concluded that nitric oxide participates in both the regulation of basal tone of cerebral microvessels and the autoregulation of CBF.


Journal of Cerebral Blood Flow and Metabolism | 1987

Three-dimensional mapping of local cerebral perfusion in alcoholic encephalopathy with and without Wernicke-Korsakoff syndrome

Takashi Hata; John S. Meyer; Norio Tanahashi; Yoshiki Ishikawa; Akira Imai; Tamotsu Shinohara; Maria Velez; William E. Fann; Prasab Kandula; Fumihiko Sakai

Seventeen severe chronic alcoholic patients with and without Wernicke-Korsakoff syndrome (WKS) were examined prospectively after being treated by withdrawal from alcohol. The WKS patients also received thiamine supplements. Three-dimensional measurements of local cerebral blood flow (LCBF) and local partition coefficients (LΛ) were made utilizing xenon contrast computed tomography (Xe CT-CBF). Results were displayed as color-coded brain maps before and after treatment and these were correlated with neurological and cognitive examinations. Before treatment chronic alcoholics without WKS (n = 10) showed diffuse reductions of LCBF values throughout all gray matter including hypothalamus, vicinity of nucleus basalis of Meynert, thalamus, and basal ganglia. Similar, but more severe, reductions were seen in patients with WKS (n = 7), however, white matter perfusion was also reduced. In WKS, most prominent reductions of LCBF were also seen in hypothalamus and basal forebrain nuclei but thalamus, basal ganglia, and limbic systems were severely reduced. After treatment, both groups with alcoholic encephalopathy showed marked clinical improvement and cerebral perfusion was restored toward normal. Chronic alcohol abuse, in the absence of thiamine deficiency, reduces CBF by direct neurotoxic effects. If thiamine deficiency is also present, more severe and localized hemodynamic reductions are superimposed.

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Dive into the Norio Tanahashi's collaboration.

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Yuji Kato

Saitama Medical University

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Ichiro Deguchi

Saitama Medical University

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Takeshi Hayashi

Saitama Medical University

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Takuya Fukuoka

Saitama Medical University

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Hajime Maruyama

Saitama Medical University

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Masaki Takao

Saitama Medical University

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