Publications by authors named "Hidehiro Mizusawa"

323 Publications

Initiative on Rare and Undiagnosed Disease in Japan.

JMA J 2021 Apr 8;4(2):112-118. Epub 2021 Apr 8.

National Center of Neurology and Psychiatry, Tokyo, Japan.

The Initiative on Rare and Undiagnosed Diseases (IRUD) has established a unified all-Japan diagnostic and research scheme for rare and undiagnosed diseases covering the entire geographic areas and specialty/subspecialty fields. The fundamental IRUD scheme consists of six components: coordinating center (IRUD-CC), clinical center (IRUD-CL), clinical specialty subgroup (IRUD-CSS), analysis center (IRUD-AC), data center (IRUD-DC), and resource center (IRUD-RC). IRUD has registered many pedigrees with undiagnosed diseases, established their diagnoses with high diagnostic rate, identified novel causative genes and new disease entities, and promoted extensive data sharing and international collaboration. IRUD plays an important role in the national medical support network for rare and intractable diseases together with academic societies and national centers. Promotion of IRUD would be essential in elucidating causes and ultimately providing cures for rare and undiagnosed diseases.
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http://dx.doi.org/10.31662/jmaj.2021-0003DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8119020PMC
April 2021

Memorial note - Professor Asao Hirano.

Neuropathology 2020 08;40(4):317-318

National Center of Neurology and Psychiatry.

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http://dx.doi.org/10.1111/neup.12688DOI Listing
August 2020

Two distinct prions in fatal familial insomnia and its sporadic form.

Brain Commun 2019 9;1(1):fcz045. Epub 2019 Dec 9.

Department of Neurological Science, Tohoku University Graduate School of Medicine, Sendai 980-8575, Japan.

Fatal familial insomnia is a genetic prion disease, which is associated with the aspartic acid to asparagine substitution at codon 178 of the prion protein gene. Although the hallmark pathological feature is thalamic and olivary degeneration, there is a patient with an atypical fatal familial insomnia without the hallmark feature. The cause of the pathological variability is unclear. We analysed a Japanese fatal familial insomnia kindred and compared one atypical clinicopathological fatal familial insomnia phenotype case and typical fatal familial insomnia phenotype cases with transmission studies using multiple lines of knock-in mice and with protein misfolding cyclic amplification. We also analysed the transmissibility and the amplification properties of sporadic fatal insomnia. Transmission studies revealed that the typical fatal familial insomnia with thalamic and olivary degeneration showed successful transmission only using knock-in mice expressing human-mouse chimeric prion protein gene. The atypical fatal familial insomnia with spongiform changes showed successful transmission only using knock-in mice expressing bank vole prion protein gene. Two sporadic fatal insomnia cases with thalamic and olivary degeneration showed the same transmissibility as the typical fatal familial insomnia phenotype. Interestingly, one sporadic fatal insomnia case with thalamic/olivary degeneration and spongiform changes showed transmissibility of both the typical and atypical fatal familial insomnia phenotypes. Protein misfolding cyclic amplification could amplify both typical fatal familial insomnia cases and sporadic fatal insomnia cases but not the atypical fatal familial insomnia phenotype or other sporadic Creutzfeldt-Jakob disease subtypes. In addition to clinical findings and neuropathological features, the transmission properties and the amplification properties were different between the typical and atypical fatal familial insomnia phenotypes. It is suggested that two distinct prions were associated with the diversity in the fatal familial insomnia phenotype, and these two prions could also be detected in sporadic fatal insomnia.
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http://dx.doi.org/10.1093/braincomms/fcz045DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7425372PMC
December 2019

MM2-type sporadic Creutzfeldt-Jakob disease: new diagnostic criteria for MM2-cortical type.

J Neurol Neurosurg Psychiatry 2020 11 24;91(11):1158-1165. Epub 2020 Aug 24.

Department of Neurology and Neurobiology of Aging, Kanazawa University Graduate School of Medical Science, Kanazawa, Japan

Objective: To clinically diagnose MM2-cortical (MM2C) and MM2-thalamic (MM2T)-type sporadic Creutzfeldt-Jakob disease (sCJD) at early stage with high sensitivity and specificity.

Methods: We reviewed the results of Creutzfeldt-Jakob disease Surveillance Study in Japan between April 1999 and September 2019, which included 254 patients with pathologically confirmed prion diseases, including 9 with MM2C-type sCJD (MM2C-sCJD) and 10 with MM2T-type sCJD (MM2T-sCJD), and 607 with non-prion diseases.

Results: According to the conventional criteria of sCJD, 4 of 9 patients with MM2C- and 7 of 10 patients with MM2T-sCJD could not be diagnosed with probable sCJD until their death. Compared with other types of sCJD, patients with MM2C-sCJD showed slower progression of the disease and cortical distribution of hyperintensity lesions on diffusion-weighted images of brain MRI. Patients with MM2T-sCJD also showed relatively slow progression and negative results for most of currently established investigations for diagnosis of sCJD. To clinically diagnose MM2C-sCJD, we propose the new criteria; diagnostic sensitivity and specificity to distinguish 'probable' MM2C-sCJD from other subtypes of sCJD, genetic or acquired prion diseases and non-prion disease controls were 77.8% and 98.5%, respectively. As for MM2T-sCJD, clinical and laboratory features are not characterised enough to develop its diagnostic criteria.

Conclusions: MM2C-sCJD can be diagnosed at earlier stage using the new criteria with high sensitivity and specificity, although it is still difficult to diagnose MM2T-sCJD clinically.
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http://dx.doi.org/10.1136/jnnp-2020-323231DOI Listing
November 2020

Diffusion-weighted magnetic resonance imaging in dura mater graft-associated Creutzfeldt-Jakob disease.

J Neurol Sci 2020 Nov 13;418:117094. Epub 2020 Aug 13.

Department of Neurology and Neurobiology of Aging, Kanazawa University Graduate School of Medical Sciences, 13-1 Takara-machi, Kanazawa 920-8604, Japan. Electronic address:

Purpose: To elucidate the extension patterns of the hyperintense areas on diffusion-weighted magnetic resonance imaging (DW-MRI) in patients with dura mater graft-associated Creutzfeldt-Jakob disease (dCJD).

Methods: We collected the DW-MRI of dCJD cases identified by the CJD Surveillance Committee in Japan, between April 1999 and February 2018. The dCJD cases were classified into non-plaque and plaque-types. The relationship among the abnormal signals, the pathological classification, and the sites of grafting were analyzed.

Results: We collected DW-MRI of 11 patients with dCJD, all of whom were methionine homozygous at codon 129 of the prion protein gene. The age at onset was 41 (26-76) [median (range)] years, the age at dural grafting was 19 (10-53) years, and the incubation period was 22 (16-29) years. Eight dCJD cases were classified as non-plaque-type and three cases were plaque-type. Five of the non-plaque-type cases and all the plaque-type cases were pathologically confirmed. Brain DW-MRI was performed 3 (1-22) months after the onset. Most of the non-plaque-type cases showed brighter hyperintensity in the cerebral cortex and basal ganglia on the side of dural grafting. Subsequent DW-MRI showed widespread hyperintense lesions in the brain. Regarding the plaque-type cases, initial scans showed hyperintensity in the basal ganglia and the thalamus in one patient. Another patient's lesion was confined to the basal ganglia. The third patient showed no abnormalities seven months post-onset; however, serial images showed a hyperintensity confined to the thalamus.

Conclusions: Non-plaque and plaque-types demonstrated different patterns of propagation of distinct prion strains.
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http://dx.doi.org/10.1016/j.jns.2020.117094DOI Listing
November 2020

The neurology of COVID-19 revisited: A proposal from the Environmental Neurology Specialty Group of the World Federation of Neurology to implement international neurological registries.

J Neurol Sci 2020 07 7;414:116884. Epub 2020 May 7.

Pakistan International Neuroscience Society, Neurology, Aga Khan University, Karachi, Pakistan.

A comprehensive review of the neurological disorders reported during the current COVID-19 pandemic demonstrates that infection with SARS-CoV-2 affects the central nervous system (CNS), the peripheral nervous system (PNS) and the muscle. CNS manifestations include: headache and decreased responsiveness considered initial indicators of potential neurological involvement; anosmia, hyposmia, hypogeusia, and dysgeusia are frequent early symptoms of coronavirus infection. Respiratory failure, the lethal manifestation of COVID-19, responsible for 264,679 deaths worldwide, is probably neurogenic in origin and may result from the viral invasion of cranial nerve I, progressing into rhinencephalon and brainstem respiratory centers. Cerebrovascular disease, in particular large-vessel ischemic strokes, and less frequently cerebral venous thrombosis, intracerebral hemorrhage and subarachnoid hemorrhage, usually occur as part of a thrombotic state induced by viral attachment to ACE2 receptors in endothelium causing widespread endotheliitis, coagulopathy, arterial and venous thromboses. Acute hemorrhagic necrotizing encephalopathy is associated to the cytokine storm. A frontal hypoperfusion syndrome has been identified. There are isolated reports of seizures, encephalopathy, meningitis, encephalitis, and myelitis. The neurological diseases affecting the PNS and muscle in COVID-19 are less frequent and include Guillain-Barré syndrome; Miller Fisher syndrome; polyneuritis cranialis; and rare instances of viral myopathy with rhabdomyolysis. The main conclusion of this review is the pressing need to define the neurology of COVID-19, its frequency, manifestations, neuropathology and pathogenesis. On behalf of the World Federation of Neurology we invite national and regional neurological associations to create local databases to report cases with neurological manifestations observed during the on-going pandemic. International neuroepidemiological collaboration may help define the natural history of this worldwide problem.
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http://dx.doi.org/10.1016/j.jns.2020.116884DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7204734PMC
July 2020

Characterization of Sporadic Creutzfeldt-Jakob Disease and History of Neurosurgery to Identify Potential Iatrogenic Cases.

Emerg Infect Dis 2020 06;26(6):1140-1146

We previously reported a phenotype of Creutzfeldt-Jakob disease (CJD), CJD-MMiK, that could help identify iatrogenic CJD. To find cases mimicking CJD-MMiK, we investigated clinical features and pathology of 1,155 patients with diagnosed sporadic CJD or unclassified CJD with and without history of neurosurgery. Patients with history of neurosurgery more frequently had an absence of periodic sharp-wave complexes on electroencephalogram than patients without a history of neurosurgery. Among 27 patients with history of neurosurgery, 5 had no periodic sharp-wave complexes on electroencephalogram. We confirmed 1 case of CJD-MMiK and suspected another. Both had methionine homozygosity at codon 129 of the prion protein gene and hyperintensity lesions in the thalamus on magnetic resonance images of the brain, which might be a clinical marker of CJD-MMiK. A subgroup with a history of neurosurgery and clinical features mimicking dura mater graft-associated CJD might have been infected during neurosurgery and had symptoms develop after many years.
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http://dx.doi.org/10.3201/eid2606.181969DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7258447PMC
June 2020

Assessment and Rating of Motor Cerebellar Ataxias With the Kinect v2 Depth Sensor: Extending Our Appraisal.

Front Neurol 2020 11;11:179. Epub 2020 Mar 11.

Movement Disorders Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan.

Current assessment of patients with cerebellar disorders is based on conventional neurological examination that is dependent on subjective judgements. Quantitative measurement of cerebellar ataxias (CAs) is essential for assessment of evidence-based treatments and the monitoring of the progress or recovery of diseases. It may provide us a useful tool to navigate future treatments for ataxia. We developed a Kinect v2. sensor system with a novel algorithm to measure and evaluate movements for two tests of Scale for the Assessment and Rating of Ataxia (SARA): the nose-finger test and gait. For the nose-finger test, we evaluated and compared accuracy, regularities and smoothness in the movements of the index finger and the proximal limbs between cerebellar patients and control subjects. For the task of walking, we evaluated and compared stability between the two groups. The precision of the system for evaluation of movements was smaller than 2 mm. For the nose-finger test, the mildly affected patients tended to show more instability than the control subjects. For a severely affected patient, our system quantified the instability of movements of the index finger using kinematic parameters, such as fluctuations and average speed. The average speed appears to be the most sensitive parameter that contrasts between patients with CAs and control subjects. Furthermore, our system also detected the adventitious movements of more proximal body parts, such as the elbow, shoulder and head. Assessment of walking was possible only in patients with mild CAs. They demonstrated large sways and compensatory wide stances. These parameters appeared to show higher accuracy than SARA. This examiner-independent device measures movements of the points of interest of SARA more accurately than eye and further provides additional information about the ataxic movements (e.g., the adventitious movements of the elbow, shoulder and head in the nose-finger test and the wide-based walking with large oscillation in the gait task), which is out of the scope of SARA. Our new system enables more accurate scoring of SARA and further provides additional information that is not currently evaluated with SARA. Therefore, it provides an easier, more accurate and more systematic description of CAs.
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http://dx.doi.org/10.3389/fneur.2020.00179DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7078683PMC
March 2020

Impaired Adaptive Motor Learning Is Correlated With Cerebellar Hemispheric Gray Matter Atrophy in Spinocerebellar Ataxia Patients: A Voxel-Based Morphometry Study.

Front Neurol 2019 14;10:1183. Epub 2019 Nov 14.

Department of Advanced Neuroimaging, Integrative Brain Imaging Center, National Center of Neurology and Psychiatry, Tokyo, Japan.

To evaluate the degree to which recently proposed parameters measured via a prism adaptation task are correlated with changes in cerebellar structure, specifically gray matter volume (GMV), in patients with spinocerebellar degeneration (SCD). We performed whole-brain voxel-based morphometry (VBM) analysis on 3-dimensional T1-weighted images obtained from 23 patients with SCD [Spinocerebellar ataxia type 6 (SCA6), 31 (SCA31), 3/Machado-Joseph disease (SCA3/MJD), and sporadic cortical cerebellar atrophy (CCA)] and 21 sex- and age-matched healthy controls (HC group). We quantified a composite index representing adaptive motor learning abilities in a hand-reaching task with prism adaptation. After controlling for age, sex, and total intracranial volume, we analyzed group-wise differences in GMV and regional GMV correlations with the adaptive learning index. Compared with the HC group, the SCD group showed reduced adaptive learning abilities and smaller GMV widely in the lobules IV-VIII in the bilateral cerebellar hemispheres. In the SCD group, the adaptive learning index was correlated with cerebellar hemispheric atrophy in the right lobule VI, the left Crus I. Additionally, GMV of the left supramarginal gyrus showed a correlation with the adaptive learning index in the SCD group, while the supramarginal region did not accompany reduction of GMV. This study indicated that a composite index derived from a prism adaptation task was correlated with GMV of the lateral cerebellum and the supramarginal gyrus in patients with SCD. This study should contribute to the development of objective biomarkers for disease severity and progression in SCD.
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http://dx.doi.org/10.3389/fneur.2019.01183DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6871609PMC
November 2019

Longitudinal analysis of risk factors for dementia based on Mild Cognitive Impairment Screen results and questionnaire responses from healthy Japanese individuals registered in an online database.

Alzheimers Dement (N Y) 2019 2;5:347-353. Epub 2019 Aug 2.

National Center of Neurology and Psychiatry, Kodaira, Tokyo, Japan.

Introduction: Despite an urgent need for developing remedial measures against dementia, no disease-modifying drugs have been developed. Efficient protocols for participant recruitment need to be established for conducting clinical trials. To meet this need, a large-scale online registry system, the Integrated Registry of Orange Plan (IROOP), was created for healthy individuals. Although the risk factors for dementia have been discussed in our previous studies for a short interval of 6 months, some factors remain controversial. The present study aimed to explore factors affecting longitudinal changes in cognitive function for a longer interval of 18 months using the IROOP data.

Methods: This study assessed the longitudinal changes in the collated data for predicting the risk of dementia and included 473 individuals (175 men and 298 women; mean age 59.6 ± 10.1 years) registered in the IROOP between July 5, 2016 and January 15, 2018 who completed the initial questionnaire and brief assessment of cognitive function (Mild Cognitive Impairment Screen) at baseline and the regular questionnaire and the Mild Cognitive Impairment Screen at least once after baseline. Statistical analyses were performed using IBM SPSS, version 23.0, for Windows for demographic data and the MIXED procedure in SAS, version 9.4, for the linear mixed-effect model. In each analysis, the statistical significance level was set at  < .05.

Results: Mood, sleep, quality of life, and medical histories including cognition were found to influence longitudinal changes in cognitive function.

Discussion: Given the multifactorial etiology of dementia, preventive measures targeting multiple domains are required for maintaining cognitive function, instead of focusing on one lifestyle factor.
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http://dx.doi.org/10.1016/j.trci.2019.06.003DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6690416PMC
August 2019

Ataxic phenotype with altered Ca3.1 channel property in a mouse model for spinocerebellar ataxia 42.

Neurobiol Dis 2019 10 20;130:104516. Epub 2019 Jun 20.

Department of Neurology, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8655, Japan.

Spinocerebellar ataxia 42 (SCA42) is a neurodegenerative disorder recently shown to be caused by c.5144G > A (p.Arg1715His) mutation in CACNA1G, which encodes the T-type voltage-gated calcium channel Ca3.1. Here, we describe a large Japanese family with SCA42. Postmortem pathological examination revealed severe cerebellar degeneration with prominent Purkinje cell loss without ubiquitin accumulation in an SCA42 patient. To determine whether this mutation causes ataxic symptoms and neurodegeneration, we generated knock-in mice harboring c.5168G > A (p.Arg1723His) mutation in Cacna1g, corresponding to the mutation identified in the SCA42 family. Both heterozygous and homozygous mutants developed an ataxic phenotype from the age of 11-20 weeks and showed Purkinje cell loss at 50 weeks old. Degenerative change of Purkinje cells and atrophic thinning of the molecular layer were conspicuous in homozygous knock-in mice. Electrophysiological analysis of Purkinje cells using acute cerebellar slices from young mice showed that the point mutation altered the voltage dependence of Ca3.1 channel activation and reduced the rebound action potentials after hyperpolarization, although it did not significantly affect the basic properties of synaptic transmission onto Purkinje cells. Finally, we revealed that the resonance of membrane potential of neurons in the inferior olivary nucleus was decreased in knock-in mice, which indicates that p.Arg1723His Ca3.1 mutation affects climbing fiber signaling to Purkinje cells. Altogether, our study shows not only that a point mutation in CACNA1G causes an ataxic phenotype and Purkinje cell degeneration in a mouse model, but also that the electrophysiological abnormalities at an early stage of SCA42 precede Purkinje cell loss.
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http://dx.doi.org/10.1016/j.nbd.2019.104516DOI Listing
October 2019

Tyrosol Reduces Amyloid-β Oligomer Neurotoxicity and Alleviates Synaptic, Oxidative, and Cognitive Disturbances in Alzheimer's Disease Model Mice.

J Alzheimers Dis 2019 ;70(3):937-952

Department of Demyelinating Disease and Aging, National Institute of Neuroscience, NCNP, Kodaira, Tokyo, Japan.

Soluble amyloid-β (Aβ) oligomers (AβOs), which elicit neurotoxicity and synaptotoxicity, are thought to play an initiating role in the pathology of Alzheimer's disease (AD). Since AβOs are a key therapeutic target, we attempted to identify natural agents that reduce AβO neurotoxicity. Using an assay system in which primary cultured neurons are treated with AβOs, we found that Rhodiola rosea extracts and one of its main constituents, tyrosol, significantly inhibited AβO-induced caspase-3 activation. We then assessed the in vivo efficacy of tyrosol by oral administration of the compound into AD model (5XFAD) transgenic and non-transgenic mice from either 2 or 4 to 7 months of age. In both paradigms, tyrosol treatment did not affect body weights of mice. Immunohistochemical analysis revealed that the immunoreactivity of spinophilin, a dendritic synaptic protein, was significantly reduced in three hippocampal subregions of vehicle-treated AD mice compared with non-transgenic mice, which was reversed in tyrosol-treated AD mice. Tyrosol treatment also prevented the enhancement of 4-hydroxy-2-nonenal immunoreactivity in the hippocampal CA3 region of AD mice. By contrast, tyrosol administration did not affect Aβ accumulation, as evaluated by immunohistochemical and biochemical analyses. Moreover, the Barnes maze test showed that tyrosol administration modestly mitigated spatial memory impairment in AD mice. These findings collectively indicate that the natural agent tyrosol protects neurons against AβO neurotoxicity in vitro and ameliorates synaptic disturbance, oxidative stress responses, and cognitive impairment in vivo. We thus suggest that tyrosol is potentially an effective, safe, and unique drug candidate for AD.
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http://dx.doi.org/10.3233/JAD-190098DOI Listing
October 2020

Age at onset in genetic prion disease and the design of preventive clinical trials.

Neurology 2019 07 6;93(2):e125-e134. Epub 2019 Jun 6.

From Broad Institute of MIT and Harvard (E.V.M., S.M.V.), Cambridge; Analytical and Translational Genetics Unit (E.V.M.), Massachusetts General Hospital; Program in Biological and Biomedical Sciences (E.V.M., S.M.V.), Harvard Medical School, Boston; Prion Alliance (E.V.M., S.M.V.), Cambridge; Harvard Business School (M.C.O.), Boston, MA; Institut du Cerveau et de la Moelle Épinière (J.-P.B., S.H.), ICM, Inserm U 1127, CNRS UMR 7225, Sorbonne Université; Cellule Nationale de Référence des Maladies de Creutzfeldt-Jakob (J.-P.B., S.H., J.-L.P.), Assistance Publique-Hôpitaux de Paris, France; National Reference Center for TSE (I.Z., C.P., P.H., T.K.), Georg-August University, Göttingen, Germany; IRCCS-Istituto delle Scienze Neurologiche di Bologna (P.P., S.C.); Departments of Experimental, Diagnostic and Specialty Medicine (P.P.) and Biomedical and Neuromotor Sciences (S.C.), University of Bologna, Italy; National Prion Disease Pathology Surveillance Center (J.S.), Case Western Reserve University, Cleveland, OH; MRC Prion Unit at UCL (J.K., S.M.), Institute of Prion Diseases, University College London, UK; Memory and Aging Center (J.C.F., L.T.T., M.D.G.), University of California San Francisco; Australian National CJD Registry (C.S., S.J.C.), University of Melbourne, Parkville, Australia; Department of Neurological Science (T.K.), Tohoku University Graduate School of Medicine, Sendai; Department of Public Health (R.A., Y.N.), Jichi Medical University, Shimotsuke; Department of Neurology and Neurobiology of Aging (T.H., M.Y.), Kanazawa University Graduate School of Medical Sciences, Kanazawa; Department of Neurology and Neurological Science (N.S.), Tokyo Medical and Dental University; National Center of Neurology and Psychiatry (T.T., H.M.), Kodaira, Japan; Laboratory of Prion Neurobiology (R.C.), Istituto di Ricerche Farmacologiche Mario Negri IRCCS, Milan; AULSS2 Ca' Foncello Hospital (I.R.), Treviso, Italy; Spanish National Reference Center for CJD (J.d.P.-C., M.C.), Instituto de Salud Carlos III and CIBERNED, Madrid, Spain; and NHS National Prion Clinic (S.M.), National Hospital for Neurology and Neurosurgery, UCL Hospitals NHS Foundation Trust, London, WC1N 3BG, UK.

Objective: To determine whether preventive trials in genetic prion disease could be designed to follow presymptomatic mutation carriers to onset of disease.

Methods: We assembled age at onset or death data from 1,094 individuals with high penetrance mutations in the prion protein gene () in order to generate survival and hazard curves and test for genetic modifiers of age at onset. We used formulae and simulations to estimate statistical power for clinical trials.

Results: Genetic prion disease age at onset varies over several decades for the most common mutations and neither sex, parent's age at onset, nor codon 129 genotype provided additional explanatory power to stratify trials. Randomized preventive trials would require hundreds or thousands of at-risk individuals in order to be statistically powered for an endpoint of clinical onset, posing prohibitive cost and delay and likely exceeding the number of individuals available for such trials.

Conclusion: The characterization of biomarkers suitable to serve as surrogate endpoints will be essential for the prevention of genetic prion disease. Parameters such as longer trial duration, increased enrollment, and the use of historical controls in a postmarketing study could provide opportunities for subsequent determination of clinical benefit.
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http://dx.doi.org/10.1212/WNL.0000000000007745DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6656649PMC
July 2019

Prevalence and clinicoradiological features of spinocerebellar ataxia type 34 in a Japanese ataxia cohort.

Parkinsonism Relat Disord 2019 08 13;65:238-242. Epub 2019 May 13.

Department of Neurology and Neurological Science, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo, Tokyo, Japan. Electronic address:

Introduction: Spinocerebellar ataxia (SCA) type 34, a form of autosomal dominantly inherited ataxia, has recently been associated with mutations in the ELOVL4 gene. However, a genetic study of the prevalence of SCA34 in an ataxia cohort has never been reported.

Methods: We performed a mutation screening of ELOVL4 in a cohort of 153 undiagnosed index ataxia patients, selected after excluding for common SCA types, in a series of 506 Japanese index ataxia patients.

Results: Heterozygous mutation c.698C > T (p.T233M) was detected in an index patient with multisystem neurodegeneration including ataxia and erythrokeratodermia skin lesions, an archetypal skin phenotype in SCA34. The patient's father also presented with ataxia but not skin lesions. Although this mutation has been recently reported in a single English-Canadian patient, the present study confirms its cosegregation with the ataxia phenotype in the Japanese kindred. Brain magnetic resonance imaging (MRI) of the patient and his father revealed marked pontine and cerebellar atrophy as well as the hot cross bun sign, that is common in cerebellar type of multiple system atrophy and was also described in SCA34 patients harboring two other mutations: p.L168F and p.W246G.

Conclusion: This represents the first genetic study of the prevalence of SCA34 in an ataxia cohort and demonstrates its low prevalence (0.2%) in ataxia patients. The broad SCA34 clinical spectrum suggests variable multisystem neurodegeneration. Clinicians should be aware of this rare disease entity, particularly if erythrokeratodermia or the hot cross bun sign in MRI are present in undiagnosed degenerative ataxia patients.
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http://dx.doi.org/10.1016/j.parkreldis.2019.05.019DOI Listing
August 2019

Specific amyloid-β42 deposition in the brain of a Gerstmann-Sträussler-Scheinker disease patient with a P105L mutation on the prion protein gene.

Prion 2018 13;12(5-6):315-319. Epub 2018 Nov 13.

a Department of Neurology and Neurological Science , Tokyo Medical and Dental University Graduate School of Medical and Dental Sciences , Yushima Bunkyo-ku , Tokyo , Japan.

Although colocalization of amyloid β (Aβ) with prion protein (PrP) in the kuru plaque has previously been observed in the brain of prion diseases patients, the participating Aβ species has not been identified. Here, we present an immunohistochemical assessment of the brain and spinal cord of a 69-year-old Japanese female patient with Gerstmann-Sträussler-Scheinker disease with a P105L mutation on the PRNP gene (GSS-P105L). Immunohistochemical assessment of serial brain sections was performed using anti-PrP and -Aβ antibodies in the hippocampus, frontal and occipital lobes. She died 69 years after a 21-year clinical course. Immunohistochemistorical examination revealed that ~50% of the kuru plaques in the cerebrum were colocalized with Aβ, and Aβ42 was predominantly observed to be colocalized with PrP-plaques. The Aβ deposition patterns were unique, and distinct from diffuse plaques observed in the normal aging brain or Alzheimer's disease brain. The spinal cord exhibited degeneration in the lateral corticospinal tract, posterior horn, and fasciculus gracilis. We have demonstrated for the first time that Aβ42, rather than Aβ40, is the main Aβ component associated with PrP-plaques, and also the degeneration of the fasciculus gracilis in the spinal cord in GSS-P105L, which could be associated with specific clinical features of GSS-P105L.
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http://dx.doi.org/10.1080/19336896.2018.1541689DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6277180PMC
July 2019

Clinical features of the behavioural variant of frontotemporal dementia that are useful for predicting underlying pathological subtypes of frontotemporal lobar degeneration.

Psychogeriatrics 2018 Jul;18(4):307-312

National Center Hospital, National Center of Neurology and Psychiatry, Tokyo, Japan.

Background: The behavioural variant of frontotemporal dementia (bvFTD) is the most common phenotype of frontotemporal lobar degeneration (FTLD). FTLD is divided into three main pathological subtypes: tau-positive FTLD (FTLD-tau), FTLD-TAR DNA-binding protein (TDP), and FTLD-Fused in sarcoma (FUS). At present, it is difficult to predict the underlying pathological subtypes of sporadic bvFTD before a patient's death.

Methods: We retrospectively investigated the clinical features of 34 Japanese patients with sporadic bvFTD, with or without motor neuron disease (MND), who had been pathologically diagnosed with FTLD. We examined whether, and how, the clinical features differed among Pick's disease, FTLD-TDP, and FTLD-FUS patients.

Results: Six of the 34 patients developed MND during the course of bvFTD. These six bvFTD-MND patients were all pathologically diagnosed with FTLD-TDP. The other 28 patients were composed of 12 FTLD-tau patients including 11 Pick's disease patients, 8 FTLD-TDP patients, and 8 FTLD-FUS patients. A comparison of the clinical features of the three pathological subtypes of the 33 patients demonstrated that the age at onset was significantly younger in FTLD-FUS patients than in Pick's disease or FTLD-TDP patients. Furthermore, while hyperorality and dietary changes in the early stage of the disease were present in approximately 40% of Pick's disease and FTLD-FUS patients, they were absent in FTLD-TDP patients.

Conclusion: The comorbidity of MND, a younger age at onset, and hyperorality and dietary changes in the early stage may be useful clinical features for predicting underlying pathological subtypes of sporadic bvFTD. The results of our study should be confirmed by prospective studies employing a larger number of cases.
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http://dx.doi.org/10.1111/psyg.12334DOI Listing
July 2018

Progressive Encephalomyelitis with Rigidity and Myoclonus Resolving after Thymectomy with Subsequent Anasarca: An Autopsy Case.

Intern Med 2018 Dec 6;57(23):3451-3458. Epub 2018 Jul 6.

Department of Neurology and Neurological Science, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Japan.

Progressive encephalomyelitis with rigidity and myoclonus (PERM) is an autoimmune disorder involving the brainstem and spinal cord and is sometimes associated with thymoma. We encountered a 75-year-old woman with typical PERM features, glycine receptor antibody, and thymoma. Her neurologic symptoms improved after thymectomy, but she unexpectedly developed anasarca with massive pleural effusions and hypoalbuminemia and finally succumbed to death. The autopsy showed edema and mononuclear infiltration in the pleura but no neuropathological findings typical of PERM. Effective treatment of PERM can reverse the neuropathological signs of encephalomyelitis. The autoimmune nature of anasarca is possible but not proven.
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http://dx.doi.org/10.2169/internalmedicine.1238-18DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6306531PMC
December 2018

Tandem internal models execute motor learning in the cerebellum.

Proc Natl Acad Sci U S A 2018 07 25;115(28):7428-7433. Epub 2018 Jun 25.

Senior Advisor's Office, RIKEN Brain Science Institute, Wako, 351-0198 Saitama, Japan

In performing skillful movement, humans use predictions from internal models formed by repetition learning. However, the computational organization of internal models in the brain remains unknown. Here, we demonstrate that a computational architecture employing a tandem configuration of forward and inverse internal models enables efficient motor learning in the cerebellum. The model predicted learning adaptations observed in hand-reaching experiments in humans wearing a prism lens and explained the kinetic components of these behavioral adaptations. The tandem system also predicted a form of subliminal motor learning that was experimentally validated after training intentional misses of hand targets. Patients with cerebellar degeneration disease showed behavioral impairments consistent with tandemly arranged internal models. These findings validate computational tandemization of internal models in motor control and its potential uses in more complex forms of learning and cognition.
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http://dx.doi.org/10.1073/pnas.1716489115DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6048491PMC
July 2018

Iatrogenic Creutzfeldt-Jakob disease.

Handb Clin Neurol 2018 ;153:207-218

National Center of Neurology and Psychiatry, Kodaira, Japan. Electronic address:

Iatrogenic transmission of Creutzfeldt-Jakob disease (CJD) has occurred through particular medical procedures. Among them, dura mater grafts and pituitary-derived growth hormone obtained from human cadavers undiagnosed as CJD are the most frequent sources of infection. Recent advances in our knowledge about dura mater graft- and human pituitary-derived growth hormone-associated CJD patients have revealed that the combination of the infected CJD strain and the PRNP genotype of the patient determines their clinical, neuropathologic, and biochemical features. In this chapter, we summarize the clinical, neuropathologic, biochemical, and diagnostic features of dura mater graft- and human pituitary-derived growth hormone-associated CJD patients for the appropriate diagnosis of iatrogenic CJD.
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http://dx.doi.org/10.1016/B978-0-444-63945-5.00012-XDOI Listing
September 2018

Analysis of risk factors for mild cognitive impairment based on word list memory test results and questionnaire responses in healthy Japanese individuals registered in an online database.

PLoS One 2018 17;13(5):e0197466. Epub 2018 May 17.

National Center of Neurology and Psychiatry, Tokyo, Japan.

Although the development of effective therapeutic drugs and radical treatment options for dementia and Alzheimer's disease (AD) remains urgent, progress in recent clinical trials of AD drugs has been less than adequate. In order to advance the progress of clinical trials, it is necessary to establish more efficient methods of recruitment. In Japan, there are registration systems stratified by mild cognitive impairment and preclinical and clinical stages of early and advanced stage dementia, but there is no registration system for healthy individuals yet. Therefore, in the present study, we developed a large-scale, internet-based health registry to investigate factors associated with cognitive function among registered participants. A total of 1038 participants completed the initial questionnaire and word list memory test. Among these participants, 353 individuals completed a second questionnaire and memory test. Stepwise multiple regression analysis was performed using IBM SPSS version 23.0 for Windows at a statistical significance level of p<0.05. We found that mood, motivation, and a decreased ability to perform activities of daily living were significantly associated with cognitive function. The results of the present study suggest that maintaining social involvement is important to prevent decreases in physical activity, daily function, mood, and motivation.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0197466PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5957388PMC
November 2018

A diagnostic decision tree for adult cerebellar ataxia based on pontine magnetic resonance imaging.

J Neurol Sci 2018 04 12;387:187-195. Epub 2018 Feb 12.

Department of Neurology and Neurological Science, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8510, Japan.

Cerebellar ataxias (CAs) are heterogeneous conditions often require differential diagnosis. This study aimed to establish a diagnostic decision tree for differentiating CAs based on pontine MRI findings. Two-hundred and two consecutive ataxia patients were clinically classified into 4 groups: (1) spinocerebellar ataxia (SCA) with brainstem involvement (SCA-BSI), (2) Pure cerebellar SCA, (3) cerebellar dominant multiple system atrophy (MSA-c), and (4) Other CA. Signal intensity in pons was graded into 3 types: hot cross bun sign (HCBS), pontine midline linear T2-hyperintensity (PMH), or normal. The distance ratio of pontine base to tegmentum, named "BT-ratio", was measured. The presence of HCBS indicated either MSA-c with a specificity of 97.7%, or SCA2. When PMH was observed, a BT-ratio above 3.54 strongly indicated SCA-BSI, namely Machado-Joseph disease, SCA1, or dentatorubral-pallidoluysian atrophy, whereas a BT-ratio below 3.54 indicated MSA-c or SCA2. When the signal intensity was normal, a BT-ratio above 3.52 indicated SCA-BSI, whereas a BT-ratio below 3.52 suggested Pure cerebellar SCA or Other CA with pure cerebellar type. The decision tree was confirmed useful in a different 30 CA patients. We propose that differential diagnosis of CAs can be supported by combining pontine MRI signal intensity changes and BT-ratio.
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http://dx.doi.org/10.1016/j.jns.2018.02.022DOI Listing
April 2018

Update: Dura Mater Graft-Associated Creutzfeldt-Jakob Disease - Japan, 1975-2017.

MMWR Morb Mortal Wkly Rep 2018 Mar 9;67(9):274-278. Epub 2018 Mar 9.

Creutzfeldt-Jakob disease (CJD) is a fatal neurodegenerative disorder that, according to the most well accepted hypothesis (1), is caused by replicating, transmissible, abnormal forms of a host-encoded prion protein (prions). Most CJD cases occur spontaneously (sporadic CJD) or are inherited (genetic CJD). Iatrogenic CJD can occur after exposure to prion-contaminated instruments or products in medical/surgical settings. Cadaveric dura mater graft-associated CJD (dCJD) accounts for a common form of iatrogenic CJD. This report summarizes the epidemiologic features of 154 cases of dCJD identified in Japan during 1975-2017; these cases account for >60% of dCJD cases reported worldwide (1,2). The unusually high prevalence of dCJD in Japan was first reported in 1997 (3). In 2008, a single brand of graft (Lyodura [B. Braun Melsungen AG, Melsungen, Germany]), frequently used as a patch in neurosurgical procedures, was identified as the probable vehicle of transmission (4). No international recall of the implicated Lyodura occurred, the product had a relatively long shelf life, and the grafts were used frequently in Japanese patients with non-life-threatening conditions (4,5). Since 2008, additional cases have been ascertained, reflecting the identification of previously missed cases and the occurrence of new cases with longer latency periods (interval from exposure to symptom onset) for dCJD (up to 30 years), underscoring the importance of maintaining surveillance for dCJD.
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http://dx.doi.org/10.15585/mmwr.mm6709a3DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5844283PMC
March 2018

Comprehensive systematic review summary: Treatment of cerebellar motor dysfunction and ataxia: Report of the Guideline Development, Dissemination, and Implementation Subcommittee of the American Academy of Neurology.

Neurology 2018 03 9;90(10):464-471. Epub 2018 Feb 9.

From the Department of Neurology (T.A.Z., J.D. Shaw), University of South Florida, Tampa; Department of Neurology (G.W.), Emory University, Atlanta, GA; Department of Neurology (S.-H.K.), Columbia University, New York, NY; Department of Neurology (S.P.), University of California, Los Angeles; Department of Neurology (P.E.G.), Beth Israel Deaconess Medical Center, Boston, MA; Shire (S.H.Y.), Lexington, MA, and the Johns Hopkins University School of Medicine, Baltimore, MD; Department of Neurology (T.A.), Houston Methodist Research Institute, TX; Department of Neurology (S.H.S., M.J.A.), University of Florida College of Medicine, Gainesville; Department of Neurology (J.D. Schmahmann), Massachusetts General Hospital, and Department of Neurology, Harvard Medical School, Boston, MA; Department of Neurology (K.P.F.), University of Utah, Salt Lake City; National Center of Neurology and Psychiatry (H.M.), Tokyo, Japan; Department of Neurology and Hertie-Institute for Clinical Brain Research (L.S.), Tübingen, Germany; Department of Neurology (R.M.D., G.S.D.), University of Kansas Medical Center, Kansas City; and Jiann-Ping Hsu College of Public Health (K.L.S.), Georgia Southern University, Statesboro.

Objective: To systematically review evidence regarding ataxia treatment.

Methods: A comprehensive systematic review was performed according to American Academy of Neurology methodology.

Conclusions: For patients with episodic ataxia type 2, 4-aminopyridine 15 mg/d probably reduces ataxia attack frequency over 3 months (1 Class I study). For patients with ataxia of mixed etiology, riluzole probably improves ataxia signs at 8 weeks (1 Class I study). For patients with Friedreich ataxia or spinocerebellar ataxia (SCA), riluzole probably improves ataxia signs at 12 months (1 Class I study). For patients with SCA type 3, valproic acid 1,200 mg/d possibly improves ataxia at 12 weeks. For patients with spinocerebellar degeneration, thyrotropin-releasing hormone possibly improves some ataxia signs over 10 to 14 days (1 Class II study). For patients with SCA type 3 who are ambulatory, lithium probably does not improve signs of ataxia over 48 weeks (1 Class I study). For patients with Friedreich ataxia, deferiprone possibly worsens ataxia signs over 6 months (1 Class II study). Data are insufficient to support or refute the use of numerous agents. For nonpharmacologic options, in patients with degenerative ataxias, 4-week inpatient rehabilitation probably improves ataxia and function (1 Class I study); transcranial magnetic stimulation possibly improves cerebellar motor signs at 21 days (1 Class II study). For patients with multiple sclerosis-associated ataxia, the addition of pressure splints possibly has no additional benefit compared with neuromuscular rehabilitation alone (1 Class II study). Data are insufficient to support or refute use of stochastic whole-body vibration therapy (1 Class III study).
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http://dx.doi.org/10.1212/WNL.0000000000005055DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5863491PMC
March 2018

Biochemical features of genetic Creutzfeldt-Jakob disease with valine-to-isoleucine substitution at codon 180 on the prion protein gene.

Biochem Biophys Res Commun 2018 02 31;496(4):1055-1061. Epub 2018 Jan 31.

Department of Neurology and Neurological Science, Tokyo Medical and Dental University Graduate School of Medical and Dental Sciences, 1-5-45 Yushima Bunkyo-ku, Tokyo 113-8510, Japan.

Valine-to-isoleucine substitution at codon 180 of the prion protein gene is only observed in patients with Creutzfeldt-Jakob disease and accounts for approximately half of all cases of genetic prion disease in Japan. In the present study, we investigated the biochemical characteristics of valine-to-isoleucine substitution at codon 180 in the prion protein gene, using samples obtained from the autopsied brains of seven patients with genetic Creutzfeldt-Jakob disease exhibiting this mutation (diagnoses confirmed via neuropathological examination). Among these patients, we observed an absence of diglycosylated and monoglycosylated forms of PrP at codon 181. Our findings further indicated that the abnormal prion proteins were composed of at least three components, although smaller carboxyl-terminal fragments were predominant. Western blot analyses revealed large amounts of PrP in the cerebral neocortices, where neuropathological examination revealed marked spongiosis. Relatively smaller amounts of PrP were detected in the hippocampus, where milder spongiosis was observed, than in the cerebral neocortex. These findings indicate that abnormal prion proteins in the neocortex are associated with severe toxicity, resulting in severe spongiosis. Our findings further indicate that the valine-to-isoleucine substitution is not a polymorphism, but rather an authentic pathogenic mutation associated with specific biochemical characteristics that differ from those observed in sporadic Creutzfeldt-Jakob disease.
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http://dx.doi.org/10.1016/j.bbrc.2018.01.119DOI Listing
February 2018

Idiopathic cerebellar ataxia (IDCA): Diagnostic criteria and clinical analyses of 63 Japanese patients.

J Neurol Sci 2018 Jan 7;384:30-35. Epub 2017 Nov 7.

Department of Neurology, The National Center Hospital, National Center of Neurology and Psychiatry, 4-1-1 Ogawa-Higashi, Kodaira, Tokyo 187-8551, Japan.

Cortical cerebellar atrophy (CCA) and multiple system atrophy with predominant cerebellar ataxia (MSA-C) are the two major forms of adult-onset sporadic ataxia. Contrary to MSA-C, there are neither diagnostic criteria nor neuroimaging features pathognomonic for CCA. Therefore, it is assumed that the category of CCA in the Japanese national registry include heterogeneous cerebellar ataxic disorders. To refine this category in more detail, we here used a clinical-based term, "idiopathic cerebellar ataxia (IDCA)", and proposed its diagnostic criteria. We collected 346 consecutive patients with the core features of the criteria (sporadic, insidious-onset and slowly progressive cerebellar ataxia in adults, and cerebellar atrophy on brain imaging). Of these, 212 (61.3%) were diagnosed with probable or possible MSA, and 30, who did not meet the diagnostic criteria for MSA at examination, were also excluded because of MRI findings suggestive of MSA. Twenty two were proven to have hereditary spinocerebellar ataxias by genetic testing, and 19 had secondary ataxias. Finally, the remaining 63 (18.2%) were diagnosed with IDCA. The mean (standard deviation) age at onset was 57.2 (10.8) years. Of these, 25 (39.7%) showed pure cerebellar ataxia, and the remaining 38 (60.3%) had some of extracerebellar features including abnormal tendon reflexes (46.0%), positive Babinski sign (9.5%), sensory disturbance (12.7%), cognitive impairment (9.5%), and involuntary movements (7.9%). Our results show that IDCA refined by the diagnostic criteria still includes clinically and genetically heterogeneous ataxic disorders. More extensive genetic analyses will be of significance for further clarification of this group.
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http://dx.doi.org/10.1016/j.jns.2017.11.008DOI Listing
January 2018

Sequence configuration of spinocerebellar ataxia type 8 repeat expansions in a Japanese cohort of 797 ataxia subjects.

J Neurol Sci 2017 Nov 31;382:87-90. Epub 2017 Aug 31.

Department of Neurology and Neurological Science, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8519, Japan.

Spinocerebellar ataxia type 8 (SCA8), an autosomal dominant neurodegenerative disorder showing slowly progressive cerebellar ataxia, is caused by a tri-nucleotide CTG repeat expansion (CTGexp) in the SCA8 gene. As the CTGexp is not fully penetrant, the significance of screening CTGexp in ataxia subjects remains obscure. We tested SCA8 CTGexp in a cohort of 797 ataxia subjects, and if present, its sequence configuration was analyzed. CTGexp was found in 16 alleles from 14 individuals, 2 of which was homozygous for CTGexp. Nucleotide sequencing disclosed 3 types of CTGexp sequence configurations: uninterrupted CTGexp, tri-nucleotide CTA interruption and CCG interruption. The 2 individuals with homozygous expansions were both sporadic cases with clinical features compatible with SCA8, supporting gene dosage effect. Seven out of 14 CTGexp-positive subjects were also carriers of other SCA expansions [Machado-Joseph disease (n=1), SCA6 (n=3) and SCA31 (n=3)], whereas 7 others were not complicated with such major SCAs. Ages of onset in subjects with pure CTGexp tended to be earlier than those with interrupted CTGexp among the 7 subjects not complicated by major SCAs, suggesting that pure CTGexp have stronger pathogenic effect than interrupted CTGexps. The present study underscores importance of disclosing sequence configuration when testing SCA8.
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http://dx.doi.org/10.1016/j.jns.2017.08.3256DOI Listing
November 2017

The professional practice and training of neurology in the Asian and Oceanian Region: A cross-sectional survey by the Asian and Oceanian Association of Neurology (AOAN).

J Neurol Sci 2017 Nov 20;382:108-115. Epub 2017 Sep 20.

Stroke Consultant, The People 's 115 hospital - Pham Ngoc Thach School of Medicine, 527 Thanh Thai street, Dist. 10, HCM City, Vietnam. Electronic address:

Objective: To survey AOAN member countries regarding their organizational structure, postgraduate neurology training program, and resources for neurological care provision.

Methodology: A cross-sectional survey using a 36-item questionnaire was conducted among country representatives to AOAN from August 2015 to August 2016.

Results: A total of 18/20 AOAN member countries participated in the survey. All the countries have organized association with regular meetings, election of officers and neurology training program. In 9/18 countries, professionals other than neurologists were eligible for affiliation. In 11/18 countries, prior Internal medicine training (or equivalent postgraduate housemanship) is prerequisite to neurology program. Recertification examination is not a practice, but submission of CME is required in 7/18 countries to maintain membership. 12/18 countries publish peer-reviewed journals with at least 1 issue per year. Subspecialty training is offered in 14/18 countries. The ratio of neurologist to population ranges from 1:14,000 to as low as 1:32 million with 9/18 having <1 neurologist per 100,000 population. 6/18 countries have at least 1 specialized center solely for neurological diseases. In government-funded hospitals, the lag time to be seen by a neurologist and/or obtain neuroimaging scan ranges from 1day to 3months. All except one country have several medical- and lay- advocacy or support groups for different neurological conditions.

Implications: The data generated can be used for benchmarking to improve neurological care, training, collaborative work and research in the field of neurosciences among the AOAN member countries. The paper presented several strategies used by the different organizations to increase their number of neurologists and improve the quality of training. Sharing of best practices, academic networking, exchange programs and use of telemedicine have been suggested.
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http://dx.doi.org/10.1016/j.jns.2017.09.022DOI Listing
November 2017

Re-evaluation of soluble APP-α and APP-β in cerebrospinal fluid as potential biomarkers for early diagnosis of dementia disorders.

Biomark Res 2017 22;5:28. Epub 2017 Sep 22.

National Center Hospital, NCNP, Tokyo, Japan.

Background: Because soluble (or secreted) amyloid precursor protein-β (sAPPβ) and -α (sAPPα) possibly reflect pathological features of Alzheimer's disease (AD), they are potential biomarker candidates for dementia disorders, including AD and mild cognitive impairment (MCI) due to AD (MCI-AD). However, controversial results have been reported regarding their alterations in the cerebrospinal fluid (CSF) of AD and MCI-AD patients. In this study, we re-assessed the utility of sAPPα and sAPPβ in CSF as diagnostic biomarkers of dementia disorders.

Methods: We used a modified and sensitive detection method to analyze sAPPs levels in CSF in four groups of patients: AD ( = 33), MCI-AD ( = 17), non-AD dementia ( = 27), and disease controls ( = 19). Phosphorylated tau (p-tau), total tau, and Aβ42 were also analyzed using standard methods.

Results: A strong correlation was observed between sAPPα and sAPPβ, consistent with previous reports. Both sAPPα and sAPPβ were highly correlated with p-tau and total tau, suggesting that sAPPs possibly reflect neuropathological changes in the brain. Levels of sAPPα were significantly higher in MCI-AD cases compared with non-AD and disease control cases, and those of sAPPβ were also significantly higher in MCI-AD and AD cases relative to other cases. A logistic regression analysis indicated that sAPPα and sAPPβ have good discriminative power for the diagnosis of MCI-AD.

Conclusions: Our findings collectively suggest that both sAPPs are pathologically relevant and potentially useful biomarkers for early and accurate diagnosis of dementia disorders. We also suggest that careful measurement is important in assessing the diagnostic utility of CSF sAPPs.
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http://dx.doi.org/10.1186/s40364-017-0108-5DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5610422PMC
September 2017

Subacute Supranuclear Palsy in anti-Hu Paraneoplastic Encephalitis.

Can J Neurol Sci 2017 Jul;44(4):444-446

3Department of Ophthalmology and Visual ScienceTokyo Medical and Dental UniversityBunkyo-ku,Tokyo,Japan.

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http://dx.doi.org/10.1017/cjn.2016.430DOI Listing
July 2017

Long-term Effects of Intravenous Cyclophosphamide in Combination with Mesna Provided Intravenously and via Bladder Perfusion in a Patient with Severe Multifocal Motor Neuropathy.

Intern Med 2017 15;56(14):1893-1896. Epub 2017 Jul 15.

Department of Neurology and Neurological Science, Graduate School of Medicine, Tokyo Medical and Dental University, Japan.

A 25-year-old woman presenting with progressive muscle weakness in the distal extremities in the absence of sensory involvement for 2 years was diagnosed with multifocal motor neuropathy (MMN). Her disease was difficult to manage with various immunosuppressants, and the muscle weakness eventually progressed to involve the respiratory muscles, necessitating mechanical ventilation. Intravenous cyclophosphamide (CY) dramatically improved her symptoms, and she has since maintained her ambulatory status for 18 years with intermittent CY therapy. Because the patient presented with hemorrhagic cystitis due to CY, we also implemented mesna administration by bladder perfusion. The administration of CY should therefore be considered in patients with severe MMN that is unresponsive to standard therapy.
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http://dx.doi.org/10.2169/internalmedicine.56.8157DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5548685PMC
January 2018