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Dive into the research topics where Yuji Tomizawa is active.

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Featured researches published by Yuji Tomizawa.


Journal of the Neurological Sciences | 2009

Extensive hemispheric lesions with radiological evidence of blood–brain barrier integrity in a patient with neuromyelitis optica

Shinji Saiki; Yuji Ueno; Toshio Moritani; Takeshi Sato; Takeshi Sekine; Sumihiro Kawajiri; Satoshi Adachi; Kazumasa Yokoyama; Yuji Tomizawa; Yumiko Motoi; Nobutaka Hattori

Anti-aquaporin-4 antibody (NMO-IgG) is used as a diagnostic marker for neuromyelitis optica (NMO). Although the mechanism of spinal cord lesions in NMO has been investigated, that of extensive hemispheric lesions with brain edema remains unclear. Here we report a 36-year-old woman with NMO positive for NMO-IgG, who developed an acute disseminating encephalomyelitis (ADEM)-like episode after Mycoplasma pneumoniae infection. Brain MRI T2-weighted images demonstrated asymmetric tumefactive hyperintense lesions in the subcortical white matter. Importantly, no lesions on T1-weighted images were enhanced after intravenous gadolinium administration on serial brain MRIs, suggesting preserved integrity of the blood-brain barrier (BBB). Likewise, the corresponding apparent diffusion coefficient maps demonstrated persistent hyperintensity changes, which represented vasogenic edema associated with glial damage and consequent neuronal loss. The findings suggest possible involvement of deficient water elimination associated with seropositivity to NMO-IgG in the induction of vasogenic edema even in the presence of intact and functional BBB.


Journal of Atherosclerosis and Thrombosis | 2015

Effects of Pioglitazone for Secondary Stroke Prevention in Patients with Impaired Glucose Tolerance and Newly Diagnosed Diabetes: The J-SPIRIT Study.

Ryota Tanaka; Kazuo Yamashiro; Yasuyuki Okuma; Hideki Shimura; Shinichiro Nakamura; Yuji Ueno; Yasutaka Tanaka; Nobukazu Miyamoto; Yuji Tomizawa; Toshiki Nakahara; Yoshiaki Furukawa; Hirotaka Watada; Ryuzo Kawamori; Nobutaka Hattori; Takao Urabe

AIM Prediabetes is an independent risk factor for future stroke. However, no effective treatment has yet been established for the recurrence of stroke in patients with prediabetes. Here we investigated the effects of pioglitazone, a potent peroxisome proliferator-activated receptor-gamma agonist, for the reduction of recurrent stroke in patients with prediabetes. METHODS Participants were patients who had a symptomatic ischemic stroke or transient ischemic attack (TIA) without a history of type 2 diabetes mellitus and who were diagnosed to have IGT or newly diagnosed diabetes by a 75-g oral glucose tolerance test. These patients were randomized to either receive or not receive pioglitazone. The primary endpoint was a recurrence of ischemic stroke. RESULTS A total of 120 patients were enrolled in the study. Sixty-three patients received pioglitazone and 57 were enrolled in the control group that did not receive pioglitazone. The majority of patients (68.3%) were prescribed 15 mg of pioglitazone, while the remaining patients (31.7%) were treated with 30 mg of pioglitazone. Over a median follow-up period of 2.8 years, treatment with pioglitazone was found to be associated with a lower rate of the primary endpoint (recurrence of stroke) than that observed in the control group [event rate=4.8% pioglitazone vs 10.5% control, hazard ratio=0.62, 95% confidence interval 0.13-2.35, p=0.49]. However, differences were not statistically significant. CONCLUSIONS While this study was too underpowered to determine the effect of pioglitazone, the result failed to show beneficial effects in patients of ischemic stroke or TIA with impaired glucose tolerance and newly diagnosed diabetes.


Journal of International Medical Research | 2012

Blood—Brain Barrier Disruption is More Severe in Neuromyelitis Optica than in Multiple Sclerosis and Correlates with Clinical Disability

Yuji Tomizawa; Kazumasa Yokoyama; Shinji Saiki; Toshiyuki Takahashi; J Matsuoka; Nobutaka Hattori

OBJECTIVES: This study evaluated blood— brain barrier (BBB) integrity, using blood and cerebrospinal fluid (CSF) markers, and assessed the practicality of these markers in the differential diagnosis of neuromyelitis optica (NMO) and multiple sclerosis (MS). METHODS: This was a retrospective observational study of consecutive patients presenting with acute phase NMO or MS (first attack or relapse). Haematological tests (including antiaquaporin-4 antibody levels) and CSF parameters (using primary component analyses) were undertaken; the correlation between BBB permeability and disease severity (by Expanded Disability Status Scale [EDSS] score) was examined. RESULTS: Levels of several markers of BBB permeability were higher in patients with NMO (n = 21) than in those with MS (n = 52). The CSF: serum albumin ratio (AR) was the one of the main differentiators of NMO and MS. Additionally, there was a significant correlation between AR and clinical severity for NMO but not for MS. CONCLUSIONS: Markers of BBB permeability were significantly higher in NMO patients than in MS patients. AR was the best marker for differentiating NMO and MS. Thus, measurement of BBB disruption markers (such as AR) might help to differentiate the diagnosis of NMO and MS in acute clinical settings.


Scientific Reports | 2016

Humoral response against host-mimetic homologous epitopes of Mycobacterium avium subsp. Paratuberculosis in Japanese multiple sclerosis patients

Davide Cossu; Kazumasa Yokoyama; Leonardo Antonio Sechi; Shigeru Otsubo; Yuji Tomizawa; Eiichi Momotani; Nobutaka Hattori

Several works have demonstrated the existence of a link between Mycobacterium avium subsp. paratuberculosis (MAP) and MS in Italy. In this study, we analyzed the serology of MAP in a Japanese population while looking at several markers of MAP. Fifty MS patients, 12 clinically isolated syndrome (CIS) patients, 30 other neurological disorders (OND) patients, and 50 healthy controls (HCs) were tested using ELISA for the presence of IgG antibodies toward immunodominant epitopes MAP_0106c121-132, homologues MBP85-98, homologues IRF5424-432, MAP_402718-32, and MAP_2694295-303. MAP-positive patients were also analyzed in relation to their clinical/demographic characteristics. Amongst all peptides, only antibodies against MAP_2694295-303 were more prevalent in MS patients (30%), as compared to OND patients (3%) (p = 0.009; area under roc curve (AUC) = 0.61) and HCs (2%) (p = 0.0004; AUC = 0.65) and in CIS patients (25%) compared to HCs (p = 0.023; AUC = 0.55). Logistic regression analysis showed a higher frequency of anti-MAP_2694295-303 antibodies in the sera of oligoclonal bands positive MS patients (p = 0.2; OR = 2, 95%CI: 0.55–7.7). These findings support the view that MAP could act as a risk factor or a triggering agent of MS in some Japanese patients with a genetic susceptibility to the mycobacterium.


Case Reports in Neurology | 2015

Low Dose of Clonazepam Is Effective in the Treatment of Painless Legs and Moving Toes Syndrome: A Case Report

Sumihiro Kawajiri; Kazuyuki Noda; Aya Ikeda; Takahiro Koinuma; Yuji Tomizawa; Nobutaka Hattori; Yasuyuki Okuma

Introduction: Painless legs and moving toes syndrome (PoLMT) is a rare movement disorder characterized by flexion, extension, abduction, adduction, and torsion of toes in the absence of pain. It is considered a variant of painful legs and moving toes syndrome, which is characterized by similar movements but is accompanied by pain. Although neuropathy, spinal cord compression, brain tumor, cerebral infarction, and Wilsons disease have been reported to be associated with PoLMT, the actual cause, trigger, and mechanism remain unclear. Therefore, a standardized treatment for PoLMT is not established yet. Case Presentation: We describe a 64-year-old Japanese woman with no past medical history who presented with nonrhythmic repetitive involuntary toe movement of the left foot in the absence of pain. She was diagnosed with idiopathic PoLMT and treated with a low dose of clonazepam (0.5 mg/day). The involuntary movement disappeared completely several days after treatment. Conclusion: A low dose of clonazepam is effective in the treatment of PoLMT.


Journal of Stroke & Cerebrovascular Diseases | 2014

Cerebral infarction in a case of Parry-Romberg syndrome.

Yuji Tomizawa; Ryota Tanaka; Kiyoshi Sekiguchi; Yutaka Oji; Yasutaka Tanaka; Kazuo Yamashiro; Nobutaka Hattori

Our objective is to report a rare coexistence of Parry-Romberg disease and ischemic stroke. Here, we report the case of a 34-year-old woman with Parry-Romberg syndrome who developed cerebral infarction. This patient developed sudden left-sided weakness and was admitted to our hospital. Magnetic resonance imaging revealed acute cerebral infarction in the posterior limb of the right internal capsule. The patient had been diagnosed with Parry-Romberg syndrome at the age of 12, and she had a history of migraine without aura. Transesophageal echocardiography revealed a patent foramen ovale, but no atrial septal aneurysm or deep vein thrombosis was observed in the lower extremities. She was treated with 200 mg of aspirin and 10 mg of atorvastatin. Her symptoms gradually improved, and she was discharged 10 days after admission. Parry-Romberg syndrome is a rare disease of progressive hemifacial atrophy with unknown etiology. The potential risk factors for ischemic stroke in Parry-Romberg syndrome include ipsilateral cerebrovascular abnormality or migraine. In addition, patent foramen ovale was identified as a concomitant risk factor in our case.


Journal of Medical Case Reports | 2016

Occipital lobe seizures and subcortical T2 and T2* hypointensity associated with nonketotic hyperglycemia: a case report

Fuyuko Sasaki; Sumihiro Kawajiri; Sho Nakajima; Ai Yamaguchi; Yuji Tomizawa; Kazuyuki Noda; Nobutaka Hattori; Yasuyuki Okuma

BackgroundNonketotic hyperglycemia often causes seizures. Recently, seizures associated with nonketotic hyperglycemia have been found to be associated with subcortical T2 hypointensity on magnetic resonance imaging, especially in the occipital lobes. However, the mechanism remains unclear, although iron accumulation is suggested. We present a case of occipital lobe seizures associated with nonketotic hyperglycemia supporting the hypothesis that the mechanism of subcortical T2 hypointensity is iron accumulation using gradient-echo T2*-weighted magnetic resonance imaging.Case presentationA 65-year-old Japanese man complained of intermittent pastel-colored flashing lights. On neurological examination, he also had lower right-side quadrant hemianopia. No other abnormal neurological findings were found. On laboratory analysis, his blood glucose level was 370 mg/dL, HbA1c was 11.4 %, and serum osmolarity was 326 mOsm/L. No ketones were detected in urine. A magnetic resonance imaging scan of his head showed subcortical T2 and T2* hypointensity in his left occipital lobe. Single-photon emission computed tomography with I123-N-isopropyl-iodoamphetamine revealed hyperperfusion in the left dominant occipital lobe. These magnetic resonance imaging abnormalities resolved during clinical recovery and treatment to control his blood sugar level. Therefore, a diagnosis of occipital lobe seizures associated with nonketotic hyperglycemia was made.ConclusionsTo the best of our knowledge, this is the first case of occipital lobe seizures associated with nonketotic hyperglycemia supporting the role of iron accumulation as a mechanism for subcortical T2 hypointensity using T2*-magnetic resonance imaging.


Journal of Stroke & Cerebrovascular Diseases | 2015

Middle Cerebral Artery Occlusion Presenting as Upper Limb Monochorea

Kazuyuki Noda; Sho Nakajima; Fuyuko Sasaki; Yoshitaka Ito; Sumihiro Kawajiri; Yuji Tomizawa; Nobutaka Hattori; Takuji Yamamoto; Yasuyuki Okuma

BACKGROUND Hemichorea is usually caused by a structural lesion in the contralateral basal ganglia or subthalamic nuclei or it develops as a form of a neurologic complication including hyperglycemia. We report a rare case of a patient who developed choreic movement in the right upper extremity associated with a contralateral middle cerebral artery (MCA) occlusion. METHODS A 76-year-old man presented with chorea in the right upper limb, known as monochorea, which occurred after recovery from losing consciousness while standing. He was found to have idiopathic orthostatic hypotension. His diffusion-weighted magnetic resonance imaging did not show signal changes indicative of acute ischemic lesions. A left carotid artery angiogram showed occlusion of the left MCA. (123)I-N-isopropyl-4-iodoamphetamine single-photon emission computed tomography of the brain showed marked hypoperfusion in the left MCA territory. His cerebrovascular reserve capacity determined using acetazolamide was relatively decreased in this territory. This decrease in cerebrovascular reserve capacity, however, did not require surgical treatment, such as extracranial-intracranial bypass surgery. RESULTS The recurrence of chorea was not observed after antiplatelet therapy and instruction on how to cope with orthostatic hypotension. CONCLUSIONS It is considered that transient hemodynamic ischemia in the right basal ganglia-thalamocortical circuits because of the combination of MCA occlusion and hypotension was the underlying cause of the monochorea in this patient.Vascular imaging studies for early identification of occlusion or severe stenosis of cerebral major arteries should be carried out in patients acutely presenting with chorea, even in the absence of other clinical signs.


Internal Medicine | 2015

A Patient with the GLA p.E66Q Mutation Exhibiting Vascular Parkinsonism and Bilateral Pulvinar Lesions

Yuji Tomizawa; Ayami Okuzumi; Hiromi Shiotsuki; Kazuyuki Noda; Nobutaka Hattori; Yasuyuki Okuma

A 76-year-old man was admitted to our hospital due to gait difficulty. Brain imaging indicated bilateral pulvinar lesions and moderate white matter lesions. The serum α-galactosidase A levels were measured for the differential diagnosis of bilateral pulvinar lesions and were found to be abnormally low. Therefore, the patient was suspected to have variant Fabry disease. A GLA mutation analysis showed the p.E66Q mutation, which is speculated to be a functional polymorphism rather than a disease-causing mutation of Fabry disease. Enzyme replacement therapy did not result in a marked improvement, however, the disease progression stopped.


CNS Neuroscience & Therapeutics | 2015

Lymphomatoid Granulomatosis with Central Nervous System Involvement Successfully Treated with Cyclophosphamide, High-dose Cytarabine, Dexamethasone, Etoposide, and Rituximab (CHASER therapy) Followed by Brain Irradiation: A Case Study

Motoki Fujimaki; Sumihiro Kawajiri; Kunimoto Ichikawa; Yuji Tomizawa; Tomoko Nakazato; Kazuyuki Noda; Nobutaka Hattori; Michiaki Koike; Yasuyuki Okuma

Lymphomatoid granulomatosis (LYG) is a rare subtype of diffuse large B-cell lymphoma. It is an extranodal angiocentric and angiodestructive lymphoproliferative disease involving the lungs, skin, and central nervous system (CNS), including abundant reactive T cells with varying numbers of atypical clonal Epstein–Barr virus (EBV)-infected B cells [1]. Clinical diagnosis of LYG is difficult because of a lack of characteristic manifestations, suitable laboratory tests, and imaging findings. No optimal treatment for LYG has yet been established, especially in cases involving the CNS. Several previous reports of rituximab monotherapy, rituximab-containing chemotherapy, interferon alpha-2b, or hematopoietic stem cell transplantation have been published [2], as well as a report of cyclophosphamide (CPM), high-dose cytarabine, dexamethasone, etoposide, and rituximab (CHASER therapy) for lung lesions of LYG [3]. Spontaneous remission has also been reported in patients with LYG involving the CNS and lungs [4]. Here, we describe a case of LYG with lung onset responsive to corticosteroid treatment, but with subsequent CNS involvement resistant to corticosteroid and rituximab monotherapy, which was successfully treated with CHASER therapy followed by brain irradiation. We also propose the value of repetitive evaluation of specimens and gradient-echo T2*-weighted magnetic resonance imaging (T2*-MRI) for diagnosis of CNS involvement in LYG (CNS–LYG). A healthy 40-year-old woman presented with persistent fever, cough, and dyspnea 2 years before admission to our hospital. Thoracic computed tomography (CT) performed at a local hospital revealed diffuse ground-glass opacity with nodular lesions in both lungs (Figure 1A). Blood examination showed highly elevated soluble interleukin-2 receptor (11,726 U/ml), and slightly elevated aspartate aminotransferase (86 IU/L) and alanine transaminase (131 IU/L). EBV antiviral capsid antigen (VCA) IgG and Epstein–Barr nuclear antigen (EBNA) were positive, and EBV anti-VCA IgM was negative, indicating past EBV infection. Pathological diagnosis was performed using videoassisted thoracic surgery (VATS), revealing atypical large lymphoid cells infiltrating the regions around the blood vessels (Figure 2A). These infiltrating lymphocytes comprised a large number of CD3-positive T cells and a few large CD20-positive B cells (Figure 2B). However, the lymphocytes were negative for EBV-encoded small RNA (EBER) according to in situ hybridization. Although LYG was suspected from the results, a definitive diagnosis was not made at the time. Prednisolone (50 mg/day; 1 mg/kg/day) was administered orally. The patient’s fever and respiratory symptoms disappeared and thoracic CT revealed disappearance of the bilateral nodular lesions (Figure 1B). However, 1 month after initiation of steroid therapy, prednisolone was tapered to 30 mg/day and she developed neurological deficits, including left facial dysesthesia, dysarthria, and gait disturbance due to left dominant spastic paraplegia, limb ataxia, and sensory disturbance. CPM (100 mg/day) was added and prednisolone was repeatedly increased or decreased from 50 to 2.5 mg/day, with no improvement. The patient was therefore

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Eiichi Momotani

Tohto College of Health Sciences

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