Publications by authors named "Hideaki Mashimo"

Anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis in children often requires early immunosuppressive therapy before antibody detection. While various electroencephalogram (EEG) patterns, including extreme delta brushes (EDBs), have been reported in adults, pediatric EEG characteristics remain understudied. This study aims to assist clinicians in identifying severe cases early, potentially improving treatment outcomes through prompt intervention.

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Article Synopsis
  • The report examines the clinical features of supplementary motor area seizures in two patients, both experiencing nocturnal seizures without impaired awareness.
  • The first patient is a 13-year-old boy with a history of hand shaking to alleviate seizure stiffness, while the second is a 43-year-old man who involuntarily moved his hand during seizures.
  • The findings highlight the importance of recognizing these seizures in conjunction with voluntary movements, which can help differentiate them from non-epileptic events like psychogenic seizures.
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Purpose: Cerebellar hypoplasia and atrophy (CBHA) in children is an extremely heterogeneous group of disorders, but few comprehensive genetic studies have been reported. Comprehensive genetic analysis of CBHA patients may help differentiating atrophy and hypoplasia and potentially improve their prognostic aspects.

Methods: Patients with CBHA in 176 families were genetically examined using exome sequencing.

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SGCE myoclonus-dystonia is a monogenic form of dystonia with an autosomal dominant mode of inheritance that co-occurs with a myoclonic jerk. In this study, we present 12 Japanese patients from nine families with this disease. Targeted next-generation sequencing covering major causative genes for monogenic dystonias identified nine distinct SGCE mutations from each of the families: three nonsense, two frameshift, two missense, one in-frame 15 bp deletion, and one splice donor site mutations, of which four were previously unreported.

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Heterozygous variants in TUBB encoding one of β-tubulin isotypes are known to cause two overlapping developmental brain disorders, complex cortical dysplasia with other brain malformations (CDCBM) and congenital symmetric circumferential skin creases (CSCSC). To date, six cases of CSCSC and eight cases of CDCBM caused by nine heterozygous variants have been reported. Here we report two cases with novel de novo missense TUBB variants (NM_178014.

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Epileptic-dyskinetic encephalopathies are rare epilepsies characterized by early-onset epileptic encephalopathies (EOEEs) with involuntary movement. Herein, we investigated the impact of gene variants in epileptic-dyskinetic encephalopathies. Four independent patients from four families who exhibited involuntary movements were recruited from Tokyo Metropolitan Neurological Hospital.

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Pontocerebellar hypoplasia (PCH) is currently classified into 13 subgroups and many gene variants associated with PCH have been identified by next generation sequencing. PCH type 1 is a rare heterogeneous neurodegenerative disorder. The clinical presentation includes early-onset severe developmental delay, progressive motor neuronopathy, and cerebellar and pontine atrophy.

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Aggressive immunosuppressive therapies have been proposed to treat primary angiitis of the central nervous system (PACNS). Here, we report the first successfully stabilized case of childhood, small-vessel PACNS with intravenous immunoglobulin (IVIG) therapy. A 12-year-old boy was admitted to our hospital complaining of recurrent headaches and upper-left homonymous quadrantanopia, since the age of 11 years.

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Background: Ataxia telangiectasia is an autosomal recessive disorder characterized by cerebellar ataxia, telangiectases, immune defects, and a predisposition to malignancy. Quality of life is severely impaired by neurological symptoms. However, curative options for the neurological symptoms are limited.

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Background: Coffin-Lowry syndrome is a rare X-linked disease, caused by loss-of-function mutations in the RPS6KA3 gene. Patients exhibit severe intellectual disability with characteristic dysmorphism. As there are no specific laboratory findings to support the diagnosis of Coffin-Lowry syndrome, it may be difficult to diagnose-especially in young children, where the characteristic craniofacial features are less discernible.

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Background: Mutations in Lysine-Specific Histone Methyltransferase 2B gene (KMT2B) have been reported to be associated with complex early-onset dystonia. Almost all reported KMT2B mutations occurred de novo in the paternal germline or in the early development of the patient. We describe clinico-genetic features on four Japanese patients with novel de novo mutations and demonstrate the phenotypic spectrum of KMT2B mutations.

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[Purpose] In patients with parkinsonism, the precise mechanism of impaired voluntary cough remains poorly understood. This study used the flow-volume curve to clarify whether disordered voluntary cough reflects the freezing phenomenon. [Subjects and Methods] Case 1 was a 58-year-old female who had been suffering from progressive supranuclear palsy-pure akinesia with gait freezing.

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[Purpose] This study used an accelerometer placed close to the center of gravity to quantitatively investigate whether unexpected gait initiation aggravates start hesitation (freezing of gait in gait initiation). [Subject and Methods] The subject was a 53-year-old female who had been suffering from juvenile parkinsonism since she was aged 21 years. An alternating-treatment design was used to compare acceleration characteristics under two gait initiation conditions, which were 1) deliberate gait initiation and 2) gait initiation on a sudden "go" verbal command (sudden gait initiation), in the "on" state of the medication cycle.

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We aimed to investigate the characteristics of Parkinsonian features assessed by the unified Parkinson's disease rating scale (UPDRS) and determine their correlations with the computed tomography (CT) findings in patients with idiopathic normal pressure hydrocephalus (iNPH). The total score and the scores for arising from chair, gait, postural stability, and body hypokinesia in the motor examination section of UPDRS were significantly improved after shunt operations. Stepwise multiple regression analysis revealed that postural stability was the determinant of the gait domain score of the iNPH grading scale.

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