Shu-ichi Ikeda

Shinshu University, Shonai, Nagano, Japan

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Publications (406)1007.98 Total impact

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    ABSTRACT: We report on a patient with sporadic Creutzfeldt–Jakob disease (CJD) who showed dystonia, periodic myoclonus, and periodic sharp wave complexes (PSWCs) on EEG. The EEG–EMG polygraphic study revealed that dystonia appeared without relation to periodic myoclonus and PSWCs and that dystonia EMGs were strongly suppressed after periodic myoclonus EMGs. These findings suggest that dystonia has a pathogenesis different from that of periodic myoclonus and PSWCs, but dystonia and periodic myoclonus may be generated through the sensorimotor cortex in CJD.
    Epilepsy and Behavior Case Reports 12/2015; 4. DOI:10.1016/j.ebcr.2015.05.002
  • Junji Ikeda · Nagaaki Katoh · Yoshiki Sekijima · Shu-ichi Ikeda ·

    Amyloid 10/2015; DOI:10.3109/13506129.2015.1089860 · 2.01 Impact Factor
  • Nagaaki Katoh · Masayuki Matsuda · Shu-ichi Ikeda ·

    Amyloid 09/2015; DOI:10.3109/13506129.2015.1075972 · 2.01 Impact Factor
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    ABSTRACT: Multifocal fibrosclerosis is the term used to represent a combination of similar fibrous lesions occurring at different anatomical sites. We herein report a hypertrophic pachymeningitis patient with a soft tissue mass around the thoracic vertebral bodies. A histopathological analysis of the biopsied tissues from both lesions showed dense fibrosis and a marked infiltration of lymphocytes and plasma cells, which lead to the diagnosis of multifocal fibrosclerosis. This pathological condition closely resembles that of IgG4-related disease and is a very rare combination of manifestations. Our case suggests that hypertrophic pachymeningitis patients need to also undergo a whole body examination.
    Internal Medicine 09/2015; 54(17):2267-72. DOI:10.2169/internalmedicine.54.3230 · 0.90 Impact Factor
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    ABSTRACT: Background. Until recently, liver transplantation (Ltx) was the only available treatment for hereditary transthyretin (TTR) amyloidosis; today, however, several pharmacotherapies are tested. Herein, we present survival data from the largest available database on transplanted hereditary TTR patients to serve as a base for comparison. Methods. Liver transplantation was evaluated in a 20-year retrospective analysis of the Familial Amyloidosis Polyneuropathy World Transplant Registry. Results. From April 1990 until December 2010, data were accumulated from 77 liver transplant centers. The Registry contains 1940 patients, and 1379 are alive. Eighty-eight Ltx were performed in combination with a heart and/or kidney transplantation. Overall, 20-year survival after Ltx was 55.3%. Multivariate analysis revealed modified body mass index, early onset of disease (<50 years of age), disease duration before Ltx, and TTR) Val30Met versus non-TTR Val30Met mutations as independent significant survival factors. Early-onset patients had an expected mortality rate of 38% that of the late-onset group (P < 0.001). Furthermore, Val30Met patients had an expected mortality rate of 61% that of non-TTR Val30Met patients (P < 0.001). With each year of duration of disease before Ltx, expected mortality increased by 11% (P < 0.001). With each 100-unit increase in modified body mass index at Ltx, the expected mortality decreased to 89%of the expectedmortality (P < 0.001). Cardiovascular death wasmarkedlymore common than that observed in patients undergoing Ltx for end-stage liver disease. Conclusions. Long-term survival after Ltx, especially for early-onset TTR Val30Met patients, is excellent. The risk of delaying Ltx by testing alternative treatments, especially in earlyonset TTR Val30Met patients, requires consideration.
    Transplantation 09/2015; Online First(9). DOI:10.1097/TP.0000000000000574 · 3.83 Impact Factor
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    ABSTRACT: Transthyretin (TTR) is a homotetrameric protein that must misfold in order to form amyloid fibrils. Misfolding includes rate limiting tetramer dissociation, followed by fast tertiary structural changes of the monomer that enable aggregation. Hereditary ATTR amyloidosis is an autosomal dominant genetic disorder with systemic deposition of amyloid fibrils induced by TTR gene mutation. We identified a rare Y114H (p.Y134H) TTR variant in a Japanese patient presenting with late-onset, very mild clinical course. The patient had an extremely low serum variant TTR concentration (18% of total TTR), whereas the composition of variant TTR was 55% in amyloid fibrils in tenosynovial tissues obtained at carpal tunnel release surgery. The amyloid fibril deposits in the ATTR Y114H patient had an altered structure compared to that in wild-type ATTR patients, as determined by luminescent conjugated poly/oligo-thiophene fluorescence spectroscopy. Biophysical studies using recombinant protein showed that Y114H TTR was markedly destabilized both thermodynamically and kinetically and was highly amyloidogenic in vitro. These data suggest that extremely low serum variant Y114H TTR concentration, probably due to endoplasmic reticulum associated degradation of unstable variant TTR protein, protected this patient from severe amyloidosis, as self-assembly of the amyloidogenic intermediate is a concentration-dependent process. This article is protected by copyright. All rights reserved.
    Journal of the Peripheral Nervous System 08/2015; DOI:10.1111/jns.12143 · 2.76 Impact Factor
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    ABSTRACT: The aim of this study was to investigate the usefulness of a triaxial accelerometer for the clinical assessment of standing and gait impairment in ataxic patients quantitatively. Fifty-one patients with spinocerebellar ataxia (SCA) or multiple system atrophy with predominant cerebellar ataxia (MSA-C) and 56 healthy control subjects were enrolled. The subjects, with a triaxial accelerometer on their back, were indicated to stand for 30 s in four different conditions (eyes opened or closed, and feet apart or together) and then to walk 10 m for a total of 12 times on a flat floor at their usual walking speed. In standing analysis, the degree of body sway was assessed. In gait analysis, gait velocity, cadence, step length, step regularity (auto-correlation coefficient: AC), step repeatability (cross-correlation coefficient) and the degree of body sway (The ratio of root mean square in each direction to the root mean square vector magnitude: RMSR) were evaluated. The degree of body sway in each standing condition and all parameters in gait showed a significant difference between the patients and control subjects. The AC and RMSR values, as well as the Scale for the Assessment and Rating of Ataxia score, showed a strong correlation with disease duration. Various parameters obtained by a triaxial accelerometer can be sensitive and objective markers for the assessment and follow-up of standing and gait impairment in ataxic patients.
    08/2015; 2(1):9. DOI:10.1186/s40673-015-0028-9
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    Tomomi Kinoshita · Shu-Ichi Ikeda ·

    Internal Medicine 08/2015; 54(15):1955. DOI:10.2169/internalmedicine.54.4644 · 0.90 Impact Factor
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    ABSTRACT: Background: Mutated transthyretin-associated (ATTRm) amyloidosis with heart failure is associated with decreased longitudinal left ventricular (LV) myocardial contraction, as measured by strain Doppler echocardiography. We sought to clarify whether speckle-tracking echocardiography (STE) would provide useful information in patients with ATTRm cardiac amyloidosis. Methods: One hundred twenty-three consecutive patients with ATTRm amyloidosis were divided into 3 groups. Group 1 had no evidence of cardiac involvement (n. = 47), group 2 had heart involvement but no congestive heart failure (CHF) and/or serum brain natriuretic peptide (BNP) levels <. 100. pg/mL (n. = 35), and group 3 had heart involvement and CHF and/or serum BNP levels ≥. 100. pg/mL (n. = 41). All patients underwent standard 2-dimensional (2D), Doppler echo, and STE. Results: By standard 2D and Doppler echo, differences in parameters were only apparent between group 3 and groups 1 and 2. Global circumferential strains by STE at each LV level and LV torsion were different between group 1 and groups 2 and 3, but not between group 2 and group 3. In contrast, global longitudinal LV strain showed significant intergroup differences (- 17.3 ± 2.3%, - 13.3 ± 2.3%, - 9.9 ± 3.3% for groups 1 to 3, respectively, P<. 0.0001). Radial strain also showed significant intergroup differences for each basal LV segment. Among 41 patients who could have been followed up after 1. year, 34 patients with diflunisal treatment had shown improvement in apical rotation and torsion without deterioration in multidirectional strains. Conclusion: ATTRm cardiac amyloidosis is characterized by progressive impairment in longitudinal and basal LV radial function when global circumferential shortening and torsion remain unchanged.
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    ABSTRACT: We report a 12-year-old female citrin-deficient patient presenting with severe anorexia and body weight loss, mimicking the restricting type of anorexia nervosa (AN). She showed normal development until age 10 years when she started to play volleyball at school. She then became gradually anorexic, and her growth was stunted. At age 12, she was admitted to hospital because of severe anorexia and thinness. She was first thought to have AN, and drip infusion of glucose solution and high-calorie drinks were given, but her condition deteriorated further. She had a history of neonatal hepatitis and was therefore suspected to have citrin deficiency (CD). Genetic analysis of SLC25A13 revealed that she was compound heterozygous for 851del4 and IVS16ins3kb, and a diagnosis of CD was made. A low-carbohydrate diet with oral intake of arginine and ursodeoxycholic acid was started, and her condition gradually improved. The clinical features in our patient were similar to those of AN, and therefore AN may also be an important clinical sign in adolescent patients with CD. Copyright © 2015 by the American Academy of Pediatrics.
    PEDIATRICS 07/2015; 136(2). DOI:10.1542/peds.2014-4172 · 5.47 Impact Factor
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    Tomomi Kinoshita · Shu-Ichi Ikeda ·

    Internal Medicine 07/2015; 54(14):1831. DOI:10.2169/internalmedicine.54.4805 · 0.90 Impact Factor

  • Amyloid: the international journal of experimental and clinical investigation: the official journal of the International Society of Amyloidosis 05/2015; 22(2). DOI:10.3109/13506129.2015.1037389 · 2.01 Impact Factor
  • Yoshiki Sekijima · Kana Tojo · Hiroshi Morita · Jun Koyama · Shu-ichi Ikeda ·
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    ABSTRACT: A recent 2-year randomized controlled trial indicated that the transthyretin (TTR) tetramer stabilizer, diflunisal, inhibits polyneuropathy progression and preserves quality of life in hereditary ATTR amyloidosis. However, its long-term outcomes are unknown. Here, we report tolerance and efficacy of long-term diflunisal administration in hereditary ATTR amyloidosis. Diflunisal was administered orally at 500 mg/day to 40 Japanese hereditary ATTR amyloidosis patents who were not candidates for liver transplantation. The observation period ranged from 2 to 116 months (mean ± SD: 38.0 ± 31.2 months). Diflunisal-related adverse events included deterioration of renal function and thrombocytopenia resulting in discontinuation of the drug in three patients. Orally administered diflunisal significantly increased serum TTR concentration (p = 0.001) and stabilized TTR tetramer structure in each patient. Longitudinal analyses of data collected at baseline, 24 months, and after 24 months confirmed sustaining effects of diflunisal on both neurological and cardiac functions. Notably, ulnar compound muscle action potential amplitude, cardiac wall thickness, and ejection fraction were not deteriorated after 24 months of treatment. Diflunisal was tolerated well by most hereditary ATTR amyloidosis patients, although renal function and blood cell counts must be carefully monitored. Clinical effects of diflunisal were sustained after 2 years of treatment.
    Amyloid: the international journal of experimental and clinical investigation: the official journal of the International Society of Amyloidosis 05/2015; 22(2). DOI:10.3109/13506129.2014.997872 · 2.01 Impact Factor
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    ABSTRACT: Context Cerebrotendinous xanthomatosis (CTX) is an autosomal recessively inherited lipid storage disease caused by mutation in the CYP27A1 gene. Spinal form CTX is a rare clinical subgroup of CTX and only 14 patients from 11 families have been reported to date. Here, we report the first Asian patient with spinal form CTX showing characteristic radiological findings. Findings The patient, a 46-year-old Japanese male, developed sensory disturbance of the lower legs at 39 and spastic gait at 46 years of age. Spinal cord magnetic resonance imaging (MRI) revealed a long hyperintense lesion involving lateral corticospinal tracts and gracile tracts in the cervical and thoracic cord on T2-weighted images. Gallium-67 ((67)Ga) scintigraphy revealed abnormal uptake in the Achilles tendons and the serum cholestanol level was elevated. CYP27A1 gene analysis identified homozygous missense mutation, c.1214G>A (p.R405Q). The patient was treated with atorvastatin monotherapy, which reduced serum cholestanol to less than 50% of the pretreatment level. Conclusion Spinal form CTX should be considered in the differential diagnosis of cryptogenic myelopathy, especially in patients with a long spinal cord lesion, as treatment with chenodeoxycholic acid and/or competitive inhibitors of 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase reverse the metabolic derangement and prevent the neurologiccal dysfunction.
    The journal of spinal cord medicine 05/2015; DOI:10.1179/1079026815Z.000000000409 · 1.33 Impact Factor
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    ABSTRACT: The mitochondrial aspartate-glutamate carrier isoform 2 (citrin) and mitochondrial glycerol-3-phosphate dehydrogenase (mGPD) double-knockout mouse has been a useful model of human citrin deficiency. One of the most prominent findings has been markedly increased hepatic glycerol 3-phosphate (G3P) following oral administration of a sucrose solution. We aimed to investigate whether this change is detectable outside of the liver, and to explore the mechanism underlying the increased hepatic G3P in these mice. We measured G3P and its metabolite glycerol in plasma and urine of the mice under various conditions. Glycerol synthesis from fructose was also studied using the liver perfusion system. The citrin/mGPD double-knockout mice showed increased urine G3P and glycerol under normal, fed conditions. We also found increased plasma glycerol under fasted conditions, while oral administration of different carbohydrates or ethanol led to substantially increased plasma glycerol. Fructose infusion to the perfused liver of the double-knockout mice augmented hepatic glycerol synthesis, and was accompanied by a concomitant increase in the lactate/pyruvate (L/P) ratio. Co-infusion of either pyruvate or phenazine methosulfate, a cytosolic oxidant, with fructose corrected the high L/P ratio, leading to reduced glycerol synthesis. Overall, these findings suggest that hepatic glycerol synthesis is cytosolic NADH/NAD(+) ratio-dependent and reveal a likely regulatory mechanism for hepatic glycerol synthesis following a high carbohydrate load in citrin-deficient patients. Therefore, urine G3P and glycerol may represent potential diagnostic markers for human citrin deficiency. Copyright © 2015. Published by Elsevier B.V.
    Biochimica et Biophysica Acta 05/2015; 1852(9). DOI:10.1016/j.bbadis.2015.04.023 · 4.66 Impact Factor
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    ABSTRACT: Autoimmune synaptic encephalitis is characterized by the presence of autoantibodies against synaptic constituent receptors and manifests as neurological and psychiatric disorders. Anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis is such an autoimmune disorder that predominantly affects young women. It is associated with antibodies against the extracellular region of the NR1 subunit of postsynaptic NMDAR. Each NMDAR functions as a heterotetrameric complex that is composed of four subunits, including NR1 and NR2A, NR2B, or NR2C. Importantly, ovarian teratoma is a typical complication of anti-NMDAR encephalitis in female patients and may contain antigenic neural tissue; however, antigenic sites remain unknown in female patients without ovarian teratoma. The purpose of this study was to investigate the expression of NMDARs in the ovum. We detected NR1 and NR2B immunoreactivity in protein fractions extracted from the bovine ovary and ova by SDS-polyacrylamide gel electrophoresis and immunoblotting analysis. Immunoprecipitates digested with trypsin were analyzed by reverse phase liquid chromatography coupled to tandem mass spectrometry. We obtained the following five peptides: SPFGRFK and KNLQDR, which are consistent with partial sequences of human NR1, and GVEDALVSLK, QPTVAGAPK, and NEVMSSK, which correspond to those of NR2A, NR2B and NR2C, respectively. Immunocytochemical analysis revealed that the bovine ovum was stained with the immunoglobulin G purified from the serum of a patient with anti-NMDAR encephalitis. Taken together, we propose that the normal ovum expresses NMDARs that have strong affinity for the disease-specific IgG. The presence of NMDARs in ova may help explain why young females without ovarian teratomas are also affected by anti-NMDAR encephalitis.
    The Tohoku Journal of Experimental Medicine 03/2015; 235(3):223-31. DOI:10.1620/tjem.235.223 · 1.35 Impact Factor
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    Jun Koyama · Shu-Ichi Ikeda · Uichi Ikeda ·
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    ABSTRACT: Cardiac amyloidosis is a cardiomyopathy characterized by increased left ventricular (LV) wall thickness and normal or decreased LV cavity size. Congestive heart failure in cardiac amyloidosis is generally considered a predominantly diastolic phenomenon, with systolic dysfunction only occurring in late-stage disease. Echocardiography is a noninvasive, reproducible method of assessing cardiac features and function in cardiac amyloidosis, and some echocardiographic indices are prognostic for the amyloidoses, with M-mode and 2-dimensional echocardiography able to detect increased LV wall thickness. Moreover, Doppler flow measurements can incrementally assess diastolic LV dysfunction, which is characteristic of cardiac amyloidosis, and provide important prognostic information. Additionally, tissue Doppler imaging can detect subtle changes in both systolic and diastolic LV function, which cannot be detected by Doppler flow measurements, and LV longitudinal strain assessed by color tissue Doppler and speckle tracking echocardiography can provide more accurate LV functional and prognostic information than tissue Doppler imaging. This review describes the advances in echocardiography and its crucial role in the diagnosis and management of cardiac amyloidosis.
    Circulation Journal 03/2015; 79(4). DOI:10.1253/circj.CJ-14-1425 · 3.94 Impact Factor
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    ABSTRACT: A 57-year-old woman with familial amyloid polyneuropathy (FAP) was scheduled to undergo living-donor liver transplantation (LDLT), but the operation was cancelled because the only potential donor had chronic alcohol-related liver disease (ALD). One year later, FAP-related neurological symptoms progressed rapidly, and emergency LDLT was planned. The donor's hepatic function had returned to normal range after 1 year of abstinence. The left liver graft volume was equivalent to 37.7% of the standard liver volume (SLV) of the recipient. However, a liver biopsy revealed mild fibrosis (score: F1). LDLT was successfully performed without any complications. The recipients' neurological findings returned to normal. One year after LDLT, the liver graft volume was equivalent to about 90% of the SLV, and the fibrosis had improved. LDLT using a graft with a fibrosis score of up to F1 might be an acceptable alternative for recipients with normal hepatic function. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.
    Hepatology Research 01/2015; DOI:10.1111/hepr.12490 · 2.74 Impact Factor
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    ABSTRACT: Polyneuropathy, organomegaly, endocrinopathy, M-protein and skin changes (POEMS) syndrome is a fatal systemic disorder associated with plasma cell dyscrasia and the overproduction of the vascular endothelial growth factor (VEGF). Recently, the prognosis of POEMS was substantially improved by introduction of therapeutic intervention for myeloma. However, no randomised clinical trial has been performed because of the rarity and severity of the disease. The Japanese POEMS syndrome with Thalidomide (J-POST) Trial is a phase II/III multicentre, double-blinded, randomised, controlled trial that aims to evaluate the efficacy and safety of a 24-week treatment with thalidomide in POEMS syndrome, with an additional 48-week open-label safety study. Adults with POEMS syndrome who have no indication for transplantation are assessed for eligibility at 12 tertiary neurology centres in Japan. Patients who satisfy the eligibility criteria are randomised (1:1) to receive thalidomide (100-300 mg daily) plus dexamethasone (12 mg/m(2) on days 1-4 of a 28-day cycle) or placebo plus dexamethasone. Both treatments were administered for 24 weeks (six cycles; randomised comparative study period). Patients who complete the randomised study period or show subacute deterioration during the randomised period participate in the subsequent 48-week open-label safety study (long-term safety period). The primary end point of the study is the reduction rate of serum VEGF levels at 24 weeks. The protocol was approved by the Institutional Review Board of each hospital. The trial was notified and registered at the Pharmaceutical and Medical Devices Agency, Japan (No. 22-1716). The J-POST Trial is currently ongoing and is due to finish in August 2015. The findings of this trial will be disseminated through peer-reviewed publications and conference presentations and will also be disseminated to participants. UMIN000004179 and JMA-IIA00046. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to
    BMJ Open 01/2015; 5(1):e007330. DOI:10.1136/bmjopen-2014-007330 · 2.27 Impact Factor
  • Tomomi Kinoshita · Shu-ichi Ikeda ·

    Internal Medicine 01/2015; 54(19):2533-2533. DOI:10.2169/internalmedicine.54.4876 · 0.90 Impact Factor

Publication Stats

6k Citations
1,007.98 Total Impact Points


  • 1986-2015
    • Shinshu University
      • • Division of Neurology and Rheumatology
      • • Department of Medicine
      Shonai, Nagano, Japan
  • 2006
    • Dokkyo Medical University
      • Department of Neurology
      Totigi, Tochigi, Japan
  • 2002
    • Uppsala University
      • The Rudbeck Laboratory
      Uppsala, Uppsala, Sweden
  • 2000
    • Hamamatsu University School of Medicine
      Hamamatu, Shizuoka, Japan
  • 1994
    • University of Essex
      Colchester, England, United Kingdom
  • 1988
    • Kyushu University
      • Research Center for Genetic Information
      Fukuoka-shi, Fukuoka-ken, Japan