Authorship：Lead author   Language：Japanese   Publishing type：Research paper (scientific journal)  

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Authorship：Last author   Language：Japanese  

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File： cted_013_315.pdf

DOI： 10.18926/CTED/65081

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Language：English   Publishing type：Research paper (scientific journal)  

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Language：English   Publisher：(一社)日本てんかん学会  

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Language：Japanese   Publishing type：Research paper (scientific journal)  

File： ●村上：レイアウトpdf 2021.12.14.pdf

CiNii Books

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Authorship：Lead author,　Corresponding author   Language：English   Publisher：Cold Spring Harbor Laboratory  

<title>Abstract</title>Thioredoxin (TXN), encoded by <italic>Txn1</italic>, acts as a critical antioxidant in the defense against oxidative stress by regulating the dithiol/disulfide balance of interacting proteins. The role of TXN in the central nervous system (CNS) is largely unknown. A phenotype-driven study of <italic>N</italic>-ethyl-<italic>N</italic>-nitrosourea-mutated rats with running seizures at around five-week of age revealed the relevance of <italic>Txn1</italic> mutations to CNS disorders. Genetic mapping identified <italic>Txn1</italic>-F54L in epileptic rats. The insulin-reducing activity of <italic>Txn1</italic>-F54L rats was approximately one-third that of the wild-type. Vacuolar degeneration in the midbrain, mainly in the thalamus and the inferior colliculus, was observed in the <italic>Txn1</italic>-F54L rats. The lesions displayed neuronal and oligodendrocyte cell death. Neurons in <italic>Txn1</italic>-F54L rats showed morphological changes in the mitochondria. Vacuolar degeneration began at three weeks of age, and spontaneous repair began at seven weeks; a dramatic change from cell death to repair occurred in the midbrain during a restricted period. In conclusion, <italic>Txn1</italic> is essential for the development of the midbrain in juvenile rats.

File： 2021.10.07.463470v1.full_Txn1.pdf

DOI： 10.1101/2021.10.07.463470

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Language：English   Publisher：Cold Spring Harbor Laboratory  

<title>Abstract</title><italic>CUX2</italic> gene encodes a transcription factor that controls neuronal proliferation, dendrite branching and synapse formation, locating at the epilepsy-associated chromosomal region 12q24 that we previously identified by a genome-wide association study (GWAS) in Japanese population. A <italic>CUX2</italic> recurrent <italic>de novo</italic> variant p.E590K has been described in patients with rare epileptic encephalopathies and the gene is a candidate for the locus, however the mutation may not be enough to generate the genome-wide significance in the GWAS and whether <italic>CUX2</italic> variants appear in other types of epilepsies and physiopathological mechanisms are remained to be investigated. Here in this study, we conducted targeted sequencings of <italic>CUX2</italic>, a paralog <italic>CUX1</italic> and its short isoform <italic>CASP</italic> harboring a unique C-terminus on 271 Japanese patients with a variety of epilepsies, and found that multiple <italic>CUX2</italic> missense variants, other than the p.E590K, and some <italic>CASP</italic> variants including a deletion, predominantly appeared in patients with temporal lobe epilepsy (TLE). Human cell culture and fly dendritic arborization analyses revealed loss-of- function properties for the <italic>CUX2</italic> variants. <italic>Cux2</italic>- and <italic>Casp</italic>-specific knockout mice both showed high susceptibility to kainate, increased excitatory cell number in the entorhinal cortex, and significant enhancement in glutamatergic synaptic transmission to the hippocampus. CASP and CUX2 proteins physiologically bound to each other and co-expressed in excitatory neurons in brain regions including the entorhinal cortex. These results suggest that <italic>CUX2</italic> and <italic>CASP</italic> variants contribute to the TLE pathology through a facilitation of excitatory synaptic transmission from entorhinal cortex to hippocampus.

File： 2021.09.17.460803v1.full_CUX2.pdf

DOI： 10.1101/2021.09.17.460803

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Cold Spring Harbor Laboratory  

CUX2 gene encodes a transcription factor that controls neuronal proliferation, dendrite branching and synapse formation, locating at the epilepsy-associated chromosomal region 12q24 that we previously identified by a genome-wide association study (GWAS) in Japanese population. A CUX2 recurrent de novo variant p.E590K has been described in patients with rare epileptic encephalopathies and the gene is a candidate for the locus, however the mutation may not be enough to generate the genome-wide significance in the GWAS and whether CUX2 variants appear in other types of epilepsies and physiopathological mechanisms are remained to be investigated. Here in this study, we conducted targeted sequencings of CUX2, a paralog CUX1 and its short isoform CASP harboring a unique C-terminus on 271 Japanese patients with a variety of epilepsies, and found that multiple CUX2 missense variants, other than the p.E590K, and some CASP variants including a deletion, predominantly appeared in patients with temporal lobe epilepsy (TLE). The CUX2 variants showed abnormal localization in human cell culture analysis. While wild-type CUX2 enhances dendritic arborization in fly neurons, the effect was compromised by some of the variants. Cux2- and Casp-specific knockout mice both showed high susceptibility to kainate, increased excitatory cell number in the entorhinal cortex, and significant enhancement in glutamatergic synaptic transmission to the hippocampus. CASP and CUX2 proteins physiologically bound to each other and co-expressed in excitatory neurons in brain regions including the entorhinal cortex. These results suggest that CUX2 and CASP variants contribute to the TLE pathology through a facilitation of excitatory synaptic transmission from entorhinal cortex to hippocampus.

DOI： 10.1101/2021.09.17.460803

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Authorship：Last author   Language：Japanese   Publishing type：Research paper (bulletin of university, research institution)  

File： 2021 性的マイノリティに関する授業.pdf

DOI： 10.18926/cted/61566

CiNii Article

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File： 2021 算数障害生徒への学習支援に関する文献レビュー.pdf

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Authorship：Lead author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：Elsevier BV  

This study aimed to examine the effects of Cacna1a mutation on the phenotype of Scn1a-associated epilepsy in rats. We used rats with an N1417H missense mutation in the Scn1a gene and others with an M251K mutation in the Cacna1a gene. Scn1a/Cacna1a double mutant rats were generated by mating both Scn1a and Cacna1a mutants. We investigated general health and the epileptic phenotype in all these genotypes. The onset threshold of hyperthermia-induced seizures was examined at 5 weeks and spontaneous seizures were monitored using video-EEG recordings from 6 to 12 weeks of age. Scn1a/Cacna1a double mutants showed significantly reduced threshold for hyperthermia-sensitive seizures onset compared with the Scn1a mutants and had absence seizures having 6-7 c/s spike-wave bursts with changes in the spike-wave pattern, whereas Cacna1a mutants had regular 6-7 c/s spike-wave bursts. In Scn1a/Cacna1a double mutants, 6-7 c/s spike-wave bursts were accompanied with eyelid myoclonia and continuously shifting generalized clonic seizures, which were not observed in either Scn1a or Cacna1a mutants. Although a curvature of the spine was observed in rats of all these genotypes, the degree of curvature was more pronounced in Scn1a/Cacna1a double mutants, followed by Cacna1a and Scn1a mutants. Our results indicate that Cacna1a and Scn1a mutations mutually alter their original phenotypes in rats. The phenotype of absence seizures with eyelid myoclonia, generalized clonic seizures, and of spine curvature in the Scn1a/Cacna1a double mutants were similar to that observed in patients with Dravet syndrome.

File： 2020 Scn1a and Cacna1a mutations mutually alter their original phenotypes in rats.pdf

DOI： 10.1016/j.neuint.2020.104859

PubMed

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Authorship：Last author   Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：GID(性同一性障害)学会  

本研究の目的は学校教員や心理職になり得る大学生の性的マイノリティへの態度に及ぼす講義の効果を明らかにすることであった。中国地方にあるX国立大学の教育学部特別支援教育講座学生とY私立大学の臨床心理学を学ぶ学部学生を対象に講義を実施し、各態度尺度(因子)を従属変数とする介入を行った。いずれの調査にも回答の不備がなかった102名(受講群59名、非受講群43名)を分析の対象として、各態度尺度(因子)を従属変数とする2要因(群×調査時期)の分散分析を行った。その結果、受講群は非受講群に比べて「社会的不利」の印象が高く維持された。一方、他の態度については講義の効果が認められなかった。大学教員による性的マイノリティに関する講義が受講者の否定的態度に及ぼす効果は限定的であると考えられた。(著者抄録)

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File： 2020 映画「私の中のあなた」から考える終末期小児がんのこどもと家族がより良く生きるための支援.pdf

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Wiley  

OBJECTIVE: Neurodevelopmental disorders (NDDs) often associate with epilepsy or craniofacial malformations. Recent large-scale DNA analyses identified hundreds of candidate genes for NDDs, but a large portion of the cases still remain unexplained. We aimed to identify novel candidate genes for NDDs. METHODS: We performed exome sequencing of 95 patients with NDDs including 51 with trigonocephaly and subsequent targeted sequencing of additional 463 NDD patients, functional analyses of variant in vitro, and evaluations of autism spectrum disorder (ASD)-like phenotypes and seizure-related phenotypes in vivo. RESULTS: We identified de novo truncation variants in nine novel genes; CYP1A1, C14orf119, FLI1, CYB5R4, SEL1L2, RAB11FIP2, ZMYND8, ZNF143, and MSX2. MSX2 variants have been described in patients with cranial malformations, and our present patient with the MSX2 de novo truncation variant showed cranial meningocele and partial epilepsy. MSX2 protein is known to be ubiquitinated by an E3 ubiquitin ligase PJA1, and interestingly we found a PJA1 hemizygous p.Arg376Cys variant recurrently in seven Japanese NDD patients; five with trigonocephaly and one with partial epilepsy, and the variant was absent in 886 Japanese control individuals. Pja1 knock-in mice carrying p.Arg365Cys, which is equivalent to p.Arg376Cys in human, showed a significant decrease in PJA1 protein amount, suggesting a loss-of-function effect of the variant. Pja1 knockout mice displayed moderate deficits in isolation-induced ultrasonic vocalizations and increased seizure susceptibility to pentylenetetrazole. INTERPRETATION: These findings propose novel candidate genes including PJA1 and MSX2 for NDDs associated with craniofacial abnormalities and/or epilepsy.

File： 2020 A recurrent PJA1 variant in trigonocephaly and neurodevelopmental disorders.pdf

DOI： 10.1002/acn3.51093

PubMed

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Other Link： https://onlinelibrary.wiley.com/doi/full-xml/10.1002/acn3.51093

Authorship：Last author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：Japanese Association for Laboratory Animal Science  

File： 2020 Poor mother-offspring relationships in rats with Cacna1a mutation.pdf

DOI： 10.1538/expanim.19-0086

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Elsevier BV  

DOI： 10.1016/j.braindev.2019.07.006

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File： 2020 ADHD患児とその保護者の服薬アドヒアランス調査.pdf

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Language：English   Publishing type：Research paper (scientific journal)  

PURPOSE: This study was performed to clarify the clinical features of Japanese patients with PRRT2 mutations. METHODS: The PRRT2 gene was analyzed in 135 patients with benign infantile epilepsy (BIE) or paroxysmal kinesigenic dyskinesia (PKD) using a direct sequencing method: 92 patients had BIE alone, 25 had both BIE and PKD, and 18 had PKD alone. Of the cases, 105 were familial, and 30 were sporadic. Clinical information was collected using a structured questionnaire. RESULTS: PRRT2 mutations were identified in 104 patients. Among the familial cases, PRRT2 mutations were found in at least one individual in 21 of 28 families with BIE alone, in 26 of 27 families with infantile convulsions and choreoathetosis, and in 2 of 3 families with PKD alone. Among the sporadic cases, PRRT2 mutations were observed in 7 of 25 patients with BIE alone, in 1 of 1 patient with BIE and PKD, and in 3 of 4 patients with PKD alone. The c.649dupC mutation was the most frequent, followed by the c.981C > G mutation. Among the patients with epilepsy, the median age at BIE onset was 5 months, the median age at the last seizure was 6 months, and the median number of seizures was 5. CONCLUSION: PRRT2 mutations were found in 68% of Japanese probands with BIE or PKD. The phenotypes of BIE associated with PRRT2 mutations were consistent with those of BIE diagnosed clinically.

DOI： 10.1016/j.seizure.2019.05.017

PubMed

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Language：Japanese   Publisher：(一社)日本てんかん学会  

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Language：Japanese   Publisher：(一社)日本腎臓学会  

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Authorship：Last author,　Corresponding author   Publishing type：Research paper (scientific journal)  

File： 2019 性別違和をもつ患者の診療録から見える格好生活場面での困難さ.pdf

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File： 2019 成人期以降の性的マイノリティ当事者.pdf

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Authorship：Last author   Publishing type：Research paper (other academic)  

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Authorship：Lead author,　Corresponding author  

File： 2019 同性婚は日本で容認されるか？.pdf

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Authorship：Last author,　Corresponding author   Publishing type：Research paper (scientific journal)  

File： 2019_性的マイノリティ当事者の語り fulltext20211005-1.pdf

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Authorship：Last author   Language：English   Publishing type：Research paper (bulletin of university, research institution)  

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

We report a female patient with Dravet syndrome (DS) with erratic segmental myoclonus, the origin of which was first identified in the cerebral cortex by the detection of myoclonus-associated cortical discharges. The discharges were disclosed through jerk locked back-averaging of electroencephalogram (EEG) data using the muscle activity of myoclonus as triggers. The detected spikes on the contralateral parieto-central region preceded myoclonic muscle activity in the forearms by 28-46 ms. The patient was six months old at the time of examination, and was developing normally before seizure onset at two months of age. She suffered from recurrent afebrile or febrile generalized tonic clonic seizures that often developed into status epilepticus. Interictal EEG and brain magnetic resonance imaging (MRI) showed no significant findings. The amplitudes of the somatosensory-evoked potentials were not extremely large. She has a chromosomal microdeletion involving SCN1A and adjacent genes. (C) 2016 The Japanese Society of Child Neurology. Published by Elsevier B.V. All rights reserved.

DOI： 10.1016/j.braindev.2016.07.005

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Language：Japanese   Publisher：(一社)日本小児神経学会  

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

Febrile infection-related epilepsy syndrome (FIRES), or acute encephalitis with refractory, repetitive partial seizures (AERRPS), is an epileptic encephalopathy beginning with fever-mediated seizures. The etiology remains unclear. To elucidate the genetic background of FIRES/AERRPS (hereafter FIRES), we recruited 19 Japanese patients, genotyped polymorphisms of the IL1B, IL6, IL10, TNFA, IL1RN, SCN1A and SCN2A genes, and compared their frequency between the patients and controls. For IL1RN, the frequency of a variable number of tandem repeat (VNTR) allele, RN2, was significantly higher in the patients than in controls (p = 0.0067), and A allele at rs4251981 in 5' upstream of IL1RN with borderline significance (p = 0.015). Haplotype containing RN2 was associated with an increased risk of FIRES (OR 3.88, 95%CI 1.40-10.8, p = 0.0057). For SCN1A, no polymorphisms showed a significant association, whereas a missense mutation, R1575C, was found in two patients. For SCN2A, the minor allele frequency of G allele at rs1864885 was higher in patients with borderline significance (p = 0.011).
We demonstrated the association of IL1RN haplotype containing RN2 with FIRES, and showed a possible association of IL1RN rs4251981 G &gt; A and SCN2A rs1864885 A &gt; G, in Japanese patients. These preliminary findings suggest the involvement of multiple genetic factors in FIRES, which needs to be confirmed by future studies in a larger number of FIRES cases. (C) 2016 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.jns.2016.07.040

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Language：English   Publisher：(一社)日本てんかん学会  

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Language：Japanese   Publisher：(一社)日本医療機器学会  

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Language：Japanese   Publisher：Japanese Society of Medical Instrumentation  

DOI： 10.4286/jjmi.86.482

CiNii Article

CiNii Books

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Other Link： http://search.jamas.or.jp/link/ui/2017045190

Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER IRELAND LTD  

Objective: The importance of epileptic high-frequency oscillations (HFOs) in electroencephalogram (EEG) is growing. Action potentials generating some HFOs are observed in the vicinity of neurons in experimental animals. However electrodes that are remote from neurons, as in case of clinical situations, should not record action potentials. We propose to resolve this question by a realistic simulation of epileptic neuronal network.
Methods: The rat dentate gyrus with sclerosis was simulated in silico. We computed the current dipole moment generated by each granule cell and the field potentials in a measurement area far from neurons.
Results: The dentate gyrus was stimulated through synaptic input to evoke discharges resembling interictal epileptiform discharges, which had superimposed HFOs &lt;= 295 Hz that were recordable with remote electrodes and represented bursts of action potentials of granule cells. The increase in power of HFOs was associated with the progression of sclerosis, the reduction of GABAergic inhibition, and the increase in cell connectivity. Spectral frequency of HFOs had similar tendencies.
Conclusions: HFOs recorded with electrodes remote from neurons could actually be generated by clusters of action potentials. Significance: The phenomenon of action potentials recorded with remote electrodes can possibly extend the clinical meaning of EEG. (C) 2014 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.

DOI： 10.1016/j.clinph.2014.08.010

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Authorship：Lead author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：WILEY-BLACKWELL  

ObjectiveDevelopmental disorders including cognitive deficit, hyperkinetic disorder, and autistic behaviors are frequently comorbid in epileptic patients with SCN1A mutations. However, the mechanisms underlying these developmental disorders are poorly understood and treatments are currently unavailable. Using a rodent model with an Scn1a mutation, we aimed to elucidate the pathophysiologic basis and potential therapeutic treatments for developmental disorders stemming from Scn1a mutations.MethodsWe conducted behavioral analyses on rats with the N1417H-Scn1a mutation. With high-performance liquid chromatography, we measured dopamine and its metabolites in the frontal cortex, striatum, nucleus accumbens, and midbrain. Methylphenidate was administered intraperitoneally to examine its effects on developmental disorder-like behaviors and hyperthermia-induced seizures.ResultsBehavioral studies revealed that Scn1a-mutant rats had repetitive behavior, hyperactivity, anxiety-like behavior, spatial learning impairments, and motor imbalance. Dopamine levels in the striatum and nucleus accumbens in Scn1a-mutant rats were significantly lower than those in wild-type rats. In Scn1a-mutant rats, methylphenidate, by increasing dopamine levels in the synaptic cleft, improved hyperactivity, anxiety-like behavior, and spatial learning impairments. Surprisingly, methylphenidate also strongly suppressed hyperthermia-induced seizures.SignificanceDysfunction of the mesolimbic dopamine reward pathway may contribute to the hyperactivity and learning impairments in Scn1a-mutant rats. Methylphenidate was effective for treating hyperactivity, learning impairments, and hyperthermia-induced seizures. We propose that methylphenidate treatment may ameliorate not only developmental disorders but also epileptic seizures in patients with SCN1A mutations.

File： 2014 Methylphenidate improves learning_Epilepsia.pdf

DOI： 10.1111/epi.12750

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCI LTD  

Topical therapy is the most favored form of treatment for whitening against hyper-pigmentation and sunburn because it lends itself to self-administration, patient compliance and an absence of systemic adverse effects. However, high-molecular-weight, hydrophilic chemicals are difficult to use as transdermal delivery drugs and the use of topical drugs has been highly limited. There are now many potent tyrosinase inhibitors, for example, sulfite or kojic acid, but the efficacy of their skin transduction remains a big problem. Furthermore, melanogenesis inhibitors from natural sources have great potential, as they are considered to be safe and largely free from adverse side effects. We applied 11-arginine (11R), a cell-membrane-permeable peptide, as a transdermal delivery system with a skin delivery enhancer, pyrenbutyrate. We performed intracellular screening for melanogenesis inhibitors with 11R fused with several kinds of tyrosinase inhibitory peptides from natural sources. Of 28 tyrosinase peptides, 13 melanin synthesis inhibitory peptides were selected. Peptide No. 10 found in gliadin protein, a wheat component, most strongly inhibited melanin production. This No. 10 peptide, of only 8 amino acids, fused to 11R showed no cytotoxicity and inhibited melanin synthesis as determined through melanin content measured using an absorption spectrometer and observation with a transmission electron microscope. Next, we transduced this 11R-No. 10 into skin with an 11R transdermal delivery system after previous treatment with pyrenbutyrate and performed daily repetitive topical application for two weeks against a UV-induced sun-tanning guinea pig model. We observed a whitening effect in a model skin sample by Masson-Fontana staining and the 11R-No. 10 peptide-applied area showed significant melanogenesis inhibition. These results show that 11R using a transdermal drug delivery system with melanogenesis inhibitory peptide is a very safe and promising method for applications from cosmetics to the pharmaceutical industry. (C) 2014 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.biomaterials.2014.01.052

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCI LTD  

New anti-cancer therapy with boron neutron capture therapy (BNCT) is based on the nuclear reaction of boron-10 with neutron irradiation. The median survival of BNCT patients with glioblastoma was almost twice as long as those receiving standard therapy in a Japanese BNCT clinical trial. In this clinical trial, two boron compounds, BPA (boronophenylalanine) and BSH (sodium borocaptate), were used for BNCT. BPA is taken up into cells through amino acid transporters that are expressed highly in almost all malignant cells, but BSH cannot pass through the cell membrane and remains outside the cell. We simulated the energy transfer against the nucleus at different locations of boron from outside the cell to the nuclear region with neutron irradiation and concluded that there was a marked difference between inside and outside the cell in boron localization. To overcome this disadvantage of BSH in BNCT, we used a cell-penetrating peptide system for transduction of BSH. CPP (cell-membrane penetrating peptide) is very common peptide domains that transduce many physiologically active substances into cells in vitro and in vivo. BSH-fused CPPs can penetrate the cell membrane and localize inside a cell. To increase the boron ratio in one BSH-peptide molecule, 8BSH fused to 11R with a dendritic lysine structure was synthesized and administrated to malignant glioma cells and a brain tumor mouse model. 8BSH-11R localized at the cell nucleus and showed a very high boron value in ICP results. With neutron irradiation, the 8BSH-11R administrated group showed a significant cancer killing effect compared to the 100 times higher concentration of BSH-administrated group. We concluded that BSH-fused CPPs were one of the most improved and potential boron compounds in the next-stage BNCT trial and 8BSH-11R may be applied in the clinical setting. (C) 2013 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.biomaterials.2013.12.055

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Language：English   Publishing type：Research paper (international conference proceedings)  

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Language：Japanese   Publisher：(一社)日本臨床神経生理学会  

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Authorship：Lead author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

The aim of this study was to assess the anticonvulsant effect of carbon dioxide (CO2) on Scn1a mutation-related febrile seizures. We examined physiological changes in the blood gas levels after the induction of hyperthermia-induced seizures (HISs), which were associated with the Scn1a missense mutation. We determined the efficacy of inhalation of 5% or 10% CO2 to treat HISs. HISs were evoked in Scn1a mutant and wild-type (WT) rats by hot water baths. To determine the anticonvulsant effect of CO2 inhalation, rats were placed in a chamber filled with air or mixed gas containing 5% CO2 or 10% CO2 for 3 min, immediately after the induction of HISs. We also analyzed the blood gas levels at the end of inhalation of CO2. Hot water bathing induced a significant reduction in the partial pressure of CO2 (pCO(2)) and respiratory alkalosis in the WT and Scn1a mutant rats. HISs were evoked in 100% of the Scn1a mutant rats within 5 min, but in none of the WT rats. The Scn1a mutant rats demonstrated a higher HISs susceptibility associated with respiratory alkalosis than the WT rats. Inhalation of 10% CO2 shortened the seizure duration from 62.6 +/- 12.1 s to 15.5 +/- 1.0 s. Blood gas analysis after the inhalation of 10% CO2 demonstrated an elevated pCO(2) level and respiratory acidosis. Inhalation of 10% CO2 demonstrated a potent and fast-acting anticonvulsant effect against HISs. (C) 2013 Elsevier B.V. All rights reserved.

File： 2013 CO2 inhalation 95530ced1260ec360189758b7e073b2a.pdf

DOI： 10.1016/j.eplepsyres.2013.01.003

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Language：Japanese   Publisher：(一社)日本小児神経学会  

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Language：English   Publisher：(一社)日本小児神経学会  

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Language：Japanese   Publisher：(一社)日本小児神経学会  

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Language：Japanese   Publisher：(一社)日本小児神経学会  

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Language：Japanese   Publisher：(一社)日本小児神経学会  

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Authorship：Lead author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：ACADEMIC PRESS INC ELSEVIER SCIENCE  

Dravet syndrome is an intractable epileptic syndrome beginning in the first year of life. De novo mutations of SCN1A, which encode the Na(v)1.1 neuronal voltage-gated sodium channel, are considered the major cause of Dravet syndrome. In this study, we investigated genetic modifiers of this syndrome.
We performed a mutational analysis of all coding exons of CACNA1A in 48 subjects with Dravet syndrome. To assess the effects of CACNA1A variants on the epileptic phenotypes of Dravet syndrome, we compared clinical features in two genotype groups: 1) subjects harboring SCN1A mutations but no CACNA1A variants (n = 20) and 2) subjects with SCN1A mutations plus CACNA1A variants (n = 20). CACNA1A variants detected in patients were studied using heterologous expression of recombinant human Ca(v)2.1 in HEK 293 cells and whole-cell patch-clamp recording.
Nine CACNA1A variants, including six novel ones, were detected in 21 of the 48 subjects (43.8%). Based on the incidence of variants in healthy controls, most of the variants seemed to be common polymorphisms. However, the subjects harboring SCN1A mutations and CACNA1A variants had absence seizures more frequently than the patients with only SCN1A mutations (8/20 vs. 0/20, p = 0.002). Moreover, the former group of subjects exhibited earlier onset of seizures and more frequent prolonged seizures before one year of age, compared to the latter group of subjects. The electrophysiological properties of four of the five novel Ca(v)2.1 variants exhibited biophysical changes consistent with gain-of-function. We conclude that CACNA1A variants in some persons with Dravet syndrome may modify the epileptic phenotypes. (C) 2012 Elsevier Inc. All rights reserved.

File： 2013 CACNA1A variants may modify the epileptic phenotype of Dravet syndrome.pdf

DOI： 10.1016/j.nbd.2012.10.016

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

We examined high-frequency oscillations (HFOs) in the ictal cortical EEGs of hyperthermia-induced seizures in a rat model of febrile seizures with an SCN1A mutation as a means of investigating the pathophysiological mechanisms underlying the generation of febrile seizures. We used 13 male homozygous Scn1a-N1417H mutant rats (F344/NSlc-Scn1a(Kyo811)) and 10 wild-type control rats.
Generalized tonic-clonic seizures were induced in all mutant rats, and HFOs with frequencies ranging from 200 to 400 Hz were found to precede spikes during the clonic phases of these seizures in the ictal EEGs. The proportion of all spikes in each seizure that were associated with HFOs increased with age. In time-frequency spectra of the EEG data, the HFOs had a mean peak frequency of 301.1 +/- 65.4 Hz (range: 156.3-468.8 Hz) and a mean peak power of 24.6 +/- 3.8 dB (range: 11.4-33.4 dB); the peak power increased with age. Regarding the wild-type rats, a brief seizure without unmistakable HFOs was exceptionally induced in only one rat.
The generation mechanism of febrile seizures is still an unanswered question. The detection of HFOs from the ictal EEGs of hyperthermia-induced seizures may provide a cue to answering this open question, although in this research we were unable to provide sufficient evidence to prove that the generation of HFOs depended on the mutation. (C) 2012 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.eplepsyres.2012.07.020

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Language：Japanese   Publisher：(公社)日本小児科学会  

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

Mutations of the neuronal voltage-gated sodium channel alpha subunit type II (SCN2A) cause various epileptic syndromes, but have never been reported in association with acute encephalopathy. To validate the involvement of SCN2A mutations in acute encephalopathy, we screened 25 patients and found a novel missense mutation (Met1128Thr) in a patient With acute encephalitis with refractory, repetitive partial seizures (AERRPS). This finding suggests that SCN2A mutation is a predisposing factor for acute encephalopathy. (C) 2012 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.eplepsyres.2012.04.016

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCI LTD  

Topical therapy is the most favored form of treatment for whitening against hyperpigmentation and sunburn because it lends itself to self-administration, patient compliance, and absence of systemic adverse effects. However, transdermal delivery of hydrophilic chemicals is difficult. The main purpose of this study is to develop a delivering system of hydrophilic drugs and proteins across the skin. Hydroquinone (HQ), a well-known tyrosinase inhibitor and antimelanogenesis compound, and enhanced green fluorescent protein (EGFP) were fused with eleven poly-arginine (11R). Both HQ-11R and EGFP-11R were efficiently delivered in B16 cells, a mouse melanoma cell line. HQ-11R was as effective as HQ alone at inhibiting melanin synthesis in B16 cells. EGFP-11R was efficiently delivered into cells of the epidermis with 4-(1-pyrenyl)-butyric acid (PB), a counteranion bearing an aromatic hydrophobic moiety, in vivo, but EGFP alone or EGFP-11R without PB was not. Finally, topical application of HQ-11R with PB significantly inhibited UV irradiation-induced pigmentation in guinea pigs compared with HQ alone. These results suggest that topical therapy using poly-arginine in combination with PB is useful for the delivery of hydrophilic drugs and proteins by the transdermal route. (c) 2012 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.biomaterials.2012.04.056

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Language：Japanese   Publisher：(一社)日本てんかん学会  

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Language：Japanese   Publishing type：Research paper (scientific journal)  

DOI： 10.4044/joma.124.115

CiNii Article

CiNii Books

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCI LTD  

Protein transduction with cell-penetrating peptides such as poly-arginine and HIV TAT peptides is widely used to deliver proteins, peptides, siRNA and biologically active compounds. It has been thought that poly-arginine peptides transduce proteins in a manner dependent on the number of arginine residues and oligo-peptides such as three arginines (3R) are ineffective. Here we showed that 3R-fused proteins were effectively delivered and functioned in cells co-treated with pyrenebutyrate, a counteranion bearing an aromatic hydrophobic moiety. Little 3R was transduced in glioma cells without pyrenebutyrate whereas the oligo-arginine was effectively delivered with pyrenebutyrate. Enhanced green fluorescence protein (eGFP) fused with 3R was effectively delivered into various kinds of cells including primary cultured cells and suspended cells in the presence of pyrenebutyrate. p53 fused with 3R (3R-p53) was delivered into glioma cells without pyrenebutyrate but could not be translocated into the ncleus. In contrast, 3R-p53 was observed in nuclei of glioma cells when co-applied with pyrenebutyrate. Although 3R-p53 was delivered less effectively than 11R-p53 with pyrenebutyrate, its transcriptional activity was higher than that of 11R-p53. Moreover, a single administration of 3R-p53 with pyrenebutyrate significantly inhibited the growth of cancer cells. These results suggest protein transduction using an oligo-arginine (3R) with pyrenebutyrate to be a good tool for the delivery of functional transcription factors and a promising method of treating cancer. (C) 2012 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.biomaterials.2012.02.049

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

The neuropeptide oxytocin (OT) has been shown to exert multiple functions in both males and females, and to play a key role in the regulation of emotionality in the central nervous system (CNS). OT has an anxiolytic effect in the CNS of rodents and humans. However, the molecular mechanisms of this effect are unclear. Here we show that OT induced the expression of regulator of G-protein signaling 2 (RGS2), a regulatory factor for anxiety, in the central amygdala (CeA) of female mice. Bath application of OT increased RGS2 levels in slices of the amygdala of virgin mice. RGS2 levels in the CeA were higher in lactating mice than in virgin mice. In contrast, RGS2 levels in mice that had given birth did not increase when the pups were removed. Acute restraint stress for 4 h induced RGS2 expression within the CeA, and local administration of an OT receptor antagonist inhibited this expression. Behavioral experiments revealed that transient restraint stress had an anxiolytic effect in wild-type females, and RGS2 levels in the CeA correlated with the anxiolytic behavior. By contrast, in the OT receptor-deficient mice, restraint stress neither increased RGS2 levels in the CeA nor had an anxiolytic effect. These results suggest that OT displays an anxiolytic effect through the induction of RGS2 expression in the CNS. (C) 2012 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.brainres.2012.03.012

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Language：Japanese   Publisher：(一社)日本小児神経学会  

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Language：Japanese   Publisher：(一社)日本小児神経学会  

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Language：Japanese   Publisher：(一社)日本小児神経学会  

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Authorship：Last author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：MOSBY-ELSEVIER  

DOI： 10.1016/j.jpeds.2011.11.058

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ACADEMIC PRESS INC ELSEVIER SCIENCE  

Although synaptotagmin I, which is a calcium (Ca2+)-binding synaptic vesicle protein, may trigger soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE)-mediated synaptic vesicle exocytosis, the mechanisms underlying the interaction between these proteins remain controversial, especially with respect to the identity of the protein(s) in the SNARE complex that bind(s) to synaptotagmin and whether Ca2+ is required for their highly effective binding. To address these questions, native proteins were solubilized, immunoprecipitated from rat brain extracts, and analyzed by immunoblotting. SNARE complexes comprising syntaxin 1, 25-kDa synaptosomal-associated protein (SNAP-25), and synaptobrevin 2 were coprecipitzted with synaptotagmin I in the presence of ethylene glycol tetraacetic acid. The amount of cop recipitated proteins was significantly unaltered by the addition of Ca2+ to the brain extract. To identify the component of the SNARE complex that bound to synaptotagmin, SNARE was coexpressed with synaptotagmin in HEK293 cells and immunoprecipitated. Syntaxin, but not SNAP-25 and synaptobrevin, bound to synaptotagmin in a Ca2+-independent manner, and the binding was abolished in the presence of 1 M NaCl. Synaptotagmin contains 2 Ca2+-binding domains (C(2)A, C2B). Mutating the positively charged lysine residues in the putative effector-binding region of the C2B domain, which are critical for transmitter release, markedly inhibited synaptotagmin-syntaxin binding, while similar mutations in the C(2)A domain had no effect on binding. Synaptotagmin-syntaxin binding was reduced by mutating multiple negatively charged glutamate residues in the amino-terminal half of the syntaxin SNARE motif. These results indicate that synaptotagmin I binds to syntaxin 1 electrostatically through its C2B domain effector region in a Ca2+-independent fashion, providing biochemical evidence that synaptotagmin I binds SNARE complexes before Ca2+ influx into presynaptic nerve terminals. (C) 2011 Elsevier Inc. All rights reserved.

DOI： 10.1016/j.mcn.2011.09.007

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：WILEY-BLACKWELL  

Purpose: The occurrence of acute encephalopathy in children with Dravet syndrome has been reported sporadically. This study clarified the features of acute encephalopathy in children with Dravet syndrome.
Methods: Through the mailing list of the Annual Zao Conference on Pediatric Neurology, we collected 15 patients with clinically diagnosed Dravet syndrome, who had acute encephalopathy, defined as a condition with decreased consciousness with or without other neurologic symptoms, such as seizures, lasting for &gt; 24 h in association with infectious symptoms. Key
Findings: There were seven boys and eight girls. A mutation of the SCN1A gene was present in nine (truncation in six and missense in three). The frequency of seizures during the 3 months before the onset of acute encephalopathy was monthly in seven children and none in three. The median age at the onset of acute encephalopathy was 44 months ( range 8-184 months). All children had status epilepticus followed by coma as the initial manifestation. Two different distributions of brain lesions were observed on diffusion-weighted images during the acute phase: cerebral cortex-dominant lesions with or without deep gray matter involvement and subcortical- dominant lesions. Four children died; nine survived with severe sequelae, and two had moderate sequelae.
Significance: We must be aware that acute encephalopathy is an important complication in children with Dravet syndrome, and associated with fulminant clinical manifestations and a poor outcome.

DOI： 10.1111/j.1528-1167.2011.03311.x

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

Oxytocin (OT) levels in plasma increase during sexual response and are significantly lower in patients with depression. A drug for the treatment of sexual dysfunction, sildenafil, enhances the electrically evoked release of OT from the posterior pituitary. In this study, we showed that sildenafil had an antidepressant-like effect through activation of an OT signaling pathway. Application of sildenafil reduced depression-related behavior in male mice. The antidepressant-like effect was blocked by an OT receptor (OTR) antagonist and was absent in OTR knockout (KO) mice. Sildenafil increased the phosphorylation of cAMP response element-binding protein (CREB) in the hippocampus. The OTR antagonist inhibited sildenafil-induced CREB phosphorylation and sildenafil had no effect on CREB phosphorylation in OTR KO mice. These results suggest sildenafil to have an antidepressant-like effect through the activation of OT signaling and to be a promising drug for the treatment of depression. (C) 2011 IBRO. Published by Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.neuroscience.2011.11.001

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：JOHN LIBBEY EUROTEXT LTD  

We present two children who exhibited the characteristics of Dravet syndrome during infancy and young childhood, with SCN1A mutation, but nevertheless achieved seizure freedom for at least four years during adolescence. These patients had no episodes of convulsive status epilepticus with a duration of more than 30 minutes and their overall favourable seizure outcome may be related to the prevention of convulsive status epilepticus.

DOI： 10.1684/epd.2011.0453

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Language：Japanese   Publisher：(一社)日本てんかん学会  

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Language：Japanese   Publisher：(一社)日本てんかん学会  

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Language：Japanese   Publisher：(一社)日本てんかん学会  

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Authorship：Last author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：WILEY-BLACKWELL  

Purpose: Mutations in the SCN1A gene, which encodes the alpha 1 subunit of voltage-gated sodium channels, cause generalized epilepsy with febrile seizures plus (GEFS+) and severe myoclonic epilepsy of infancy (SMEI). N1417H-Scn1a mutant rats are considered to be an animal model of human FS+ or GEFS+. To assess the pharmacologic validity of this model, we compared the efficacies of eight different antiepileptic drugs (AEDs) for the treatment of hyperthermia-induced seizures using N1417H-Scn1a mutant rats.
Methods: AEDs used in this study included valproate, carbamazepine (CBZ), phenobarbital, gabapentin, acetazolamide, diazepam (DZP), topiramate, and potassium bromide (KBr). The effects of these AEDs were evaluated using the hot water model, which is a model of experimental FS. Five-week-old rats were pretreated with each AED and immersed in water at 45 degrees C to induce hyperthermia-induced seizures. The seizure manifestations and video-electroencephalographic recordings were evaluated. Furthermore, the effects of each AED on motor coordination and balance were assessed using the balance-beam test.
Key Findings: KBr significantly reduced seizure durations, and its anticonvulsant effects were comparable to those of DZP. On the other hand, CBZ decreased the seizure threshold. In addition, DZP and not KBr showed significant impairment in motor coordination and balance.
Significance: DZP and KBr showed potent inhibitory effects against hyperthermia-induced seizures in the Scn1a mutant rats, whereas CBZ exhibited adverse effects. These responses to hyperthermia-induced seizures were similar to those in patients with GEFS+ and SMEI. N1417H-Scn1a mutant rats may, therefore, be useful for testing the efficacy of new AEDs against FS in GEFS+ and SMEI patients.

DOI： 10.1111/j.1528-1167.2011.03046.x

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：PUBLIC LIBRARY SCIENCE  

Hair growth is a highly regulated cyclical process. Immunosuppressive immunophilin ligands such as cyclosporin A (CsA) and FK506 are known as potent hair growth modulatory agents in rodents and humans that induce active hair growth and inhibit hair follicle regression. The immunosuppressive effectiveness of these drugs has been generally attributed to inhibition of T cell activation through well-characterized pathways. Specifically, CsA and FK506 bind to intracellular proteins, principally cyclophilin A and FKBP12, respectively, and thereby inhibit the phosphatase calcineurin (Cn). The calcineurin (Cn)/NFAT pathway has an important, but poorly understood, role in the regulation of hair follicle development. Here we show that a novel-splicing variant of calcineurin A beta CnA beta-FK, which is encoded by an intron-retaining mRNA and is deficient in the autoinhibitory domain, is predominantly expressed in mature follicular keratinocytes but not in the proliferating keratinocytes of rodents. CnA beta-FK was weakly sensitive to Ca(2+) and dephosphorylated NFATc2 under low Ca(2+) levels in keratinocytes. Inhibition of Cn/NFAT induced hair growth in nude mice. Cyclin G2 was identified as a novel target of the Cn/NFATc2 pathway and its expression in follicular keratinocytes was reduced by inhibition of Cn/NFAT. Overexpression of cyclin G2 arrested the cell cycle in follicular keratinocytes in vitro and the Cn inhibitor, cyclosporin A, inhibited nuclear localization of NFATc2, resulting in decreased cyclin G2 expression in follicular keratinocytes of rats in vivo. We therefore suggest that the calcineurin/NFAT pathway has a unique regulatory role in hair follicle development.

DOI： 10.1371/journal.pone.0017685

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：OKAYAMA UNIV MED SCHOOL  

Mitochondria are important cellular organelles in most metabolic processes and have a highly dynamic nature, undergoing frequent fission and fusion. The dynamic balance between fission and fusion plays critical roles in mitochondrial functions. In recent studies, several large GTPases have been identified as key molecular factors in mitochondrial fission and fusion. Moreover, the posttranslational modifications of these large GTPases, including phosphorylation, ubiquitination and SUMOylation, have been shown to be involved in the regulation of mitochondrial dynamics. Neurons are particularly sensitive and vulnerable to any abnormalities in mitochondrial dynamics, due to their large energy demand and long extended processes. Emerging evidences have thus indicated a strong linkage between mitochondria and neurodegenerative diseases, including Alzheimer's disease, Parkinson's disease and Huntington's disease. In this review, we will describe the regulation of mitochondrial dynamics and its role in neurodegenerative diseases.

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Language：Japanese   Publisher：(公社)日本小児科学会  

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER IRELAND LTD  

A significant association between plasma oxytocin (OT) levels and depression has been demonstrated. A recent study found that sexual activity and mating with a female induced the release of OT in the central nervous system of male rats. Here we examined the effect of mating behavior on depression-related behavior in wild-type (WT) and OT receptor-deficient (OTR KO) male mice. The WT males showed a reduction in depression-related behavior after mating behavior, but the OTR KO mice did not. Application of an OTR antagonist inhibited mating behavior-induced antidepressant effect in WT males. OT may mediate the antidepressant effects of mating behavior. (C) 2010 Elsevier Ireland Ltd and the Japan Neuroscience Society. All rights reserved.

DOI： 10.1016/j.neures.2010.06.007

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Authorship：Last author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

We herein investigated risk factors of pediatric acute encephalopathy (AE) regarding the hitherto uncharacterized genetic background of seizure susceptibility underlying the pathogenesis of AE. The study included 15 patients with a history of various types of AE in childhood. We undertook the mutational analysis of the neuronal sodium channel alpha 1 subunit (SCN1A) gene which is the most representative gene for hyperthermia-induced seizure susceptibility.
Six patients (40%) had a positive family history of seizures or AE, especially febrile seizures, in first- or second-degree relatives. The SCN1A-R1575C mutation was detected in a patient with a history of acute encephalitis with refractory, repetitive partial seizures (AERRPS) and also in the patient&apos;s apparently healthy father.
In the present study, dense familial seizure predisposition was present in the patients with AE. Although the presence of seizure susceptibility alone is insufficient to cause AE, it can exacerbate seizures and the subsequent development of inflammatory reactions in the brain when environmental factors are included. Genetic seizure susceptibility may contribute to some types of AE in childhood. Crown Copyright (C) 2010 Published by Elsevier B.V. All rights reserved.

DOI： 10.1016/j.eplepsyres.2010.07.005

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

Purpose: Rasmussen&apos;s encephalitis (RE) is a progressive and catastrophic epileptic disorder caused by chronic localized encephalitis. We performed a nationwide survey of RE to assess the clinical picture, treatment effect, and prognosis of Japanese RE patients. Subjects & methods: The subjects were 27 patients (male:1 2; female: IS) from 13 medical facilities. All of them satisfied the clinical and neuroimaging criteria for RE, including 14 pathologically proven cases. Results: They were divided into the childhood-onset rapidly progressive type (CORP, n = 19), and late-onset slowly progressive type (LOSP, n = 8). The mean age at epilepsy onset was 4 years and 4 months in CORP, and 16 years in LOSP. The mean period between the onset age of epilepsy and development of frequent seizures was 1 year and 4 months in the former, and 3 years and 4 months in the latter. The immunomodulatory treatment including high-dose steroid (n = 14) and high-dose intravenous immunoglobulin therapies (IVIgG, n = 12) achieved more than a 50% reduction in the seizure frequency in 5 (36%) and 4 (33%) patients, respectively. Eight and seven patients underwent focal cortical resection and functional hemispherectomy, leading to significant improvement in 5 of the 8 patients and excellent seizure control in all 7 patients, respectively. Conclusion: Although the high-dose steroid and IVIG therapies may have alleviated the exacerbation of seizures in those with RE, they could not halt the disease progression. Functional hemispherectomy is still the only curative therapy for RE, despite the fact that the early introduction of this procedure remains controversial. (C) 2009 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.braindev.2009.10.004

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：SOC NEUROSCIENCE  

Although febrile seizures (FSs) are the most common convulsive syndrome in infants and childhood, the etiology of FSs has remained unclarified. Several missense mutations of the Na(v)1.1 channel (SCN1A), which alter channel properties, have been reported in a familial syndrome of GEFS+ (generalized epilepsy with febrile seizures plus). Here, we generated Scn1a-targeted rats carrying a missense mutation (N1417H) in the third pore region of the sodium channel by gene-driven ENU (N-ethyl-N-nitrosourea) mutagenesis. Despite their normal appearance under ordinary circumstances, Scn1a mutant rats exhibited remarkably high susceptibility to hyperthermia-induced seizures, which involve generalized clonic and/or tonic-clonic convulsions with paroxysmal epileptiform discharges. Whole-cell patch-clamp recordings from HEK cells expressing N1417H mutant channels and from hippocampal GABAergic interneurons of N1417H mutant rats revealed a significant shift of the inactivation curve in the hyperpolarizing direction. In addition, clamp recordings clearly showed the reduction in action potential amplitude in the hippocampal interneurons of these rats. These findings suggest that a missense mutation (N1417H) of the Na(v)1.1 channel confers susceptibility to FS and the impaired biophysical properties of inhibitory GABAergic neurons underlie one of the mechanisms of FS.

DOI： 10.1523/JNEUROSCI.3360-09.2010

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Authorship：Lead author,　Corresponding author   Language：Japanese   Publishing type：Research paper (conference, symposium, etc.)  

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Language：Japanese   Publisher：(一社)日本小児神経学会  

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：SPRINGER TOKYO  

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER IRELAND LTD  

DOI： 10.1016/j.neures.2009.09.084

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ACADEMIC PRESS INC ELSEVIER SCIENCE  

Mutations of SCN1A, encoding the voltage-gated sodium channel alpha l subunit, represent the most frequent genetic cause of severe myoclonic epilepsy in infancy (SMEI). The purpose of this study was to determine if mutations in other seizure susceptibility genes are also present and could modify the disease severity. All coding exons of SCN1B, GABRG2, and CACNB4 genes were screened for mutations in 38 SCN1A-mutation-positive SMEI probands. We identified one proband who was heterozygous for a de novo SCN1A nonsense mutation (R568X) and another missense mutation (R468Q) of the CACNB4 gene. The latter mutation was inherited from his father who had a history of febrile seizures. An electrophysiological analysis of heterologous expression system exhibited that R468Q-CACNB4 showed greater Ba(2+) current density compared with the wild-type CACNB4. The greater Ca(v)2.1 currents caused by the R468Q-CACNB4 mutation may increase the neurotransmitter release in the excitatory neurons under the condition of insufficient inhibitory neurons caused primarily by the SCN1A mutation. (C) 2008 Elsevier Inc. All rights reserved.

DOI： 10.1016/j.nbd.2008.07.017

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Language：English   Publisher：LIPPINCOTT WILLIAMS & WILKINS  

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Language：Japanese   Publisher：(一社)日本小児神経学会  

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：WILEY  

Purpose: Our aim was to develop a screening test to predict Dravet syndrome before the first birthday based on the clinical characteristics of infants and the SCN1A mutation analysis.
Methods: Ninety-six patients who experienced febrile seizures before the age of one were enrolled. The patients were divided into two groups-the Dravet syndrome group (n = 46) and the non-Dravet syndrome group (n = 50). We compared the clinical characteristics before one year of age of the two groups. We analyzed all coding exons of the SCN1A gene by the direct sequencing method. Scores from 0 to 3 were assigned to each risk factor based on the odds ratio and p-value.
Results: An age of onset of febrile seizure &lt;= 7 months, a total number of seizures &gt;= 5, and prolonged seizures lasting more than 10 min. were regarded as significant risk factors for Dravet syndrome. Other factors highly predictive of this syndrome were hemiconvulsions, partial seizures, myoclonic seizures, and hot water-induced seizures. A total clinical score of six or above was the cutoff value indicating a high risk of Dravet syndrome. SCN1A missense and truncated mutations were detected significantly more often in the Dravet syndrome group than in the non-Dravet syndrome group.
Discussion: This simple screening test was designed to be used by general pediatricians. It could help to predict Dravet syndrome before one year of age. If the sum of the clinical risk score is &gt;= 6, then the performance of an SCN1A mutation analysis is recommended.

DOI： 10.1111/j.1528-1167.2007.01475.x

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：BLACKWELL PUBLISHING  

Mutations in the SCN1A gene, encoding the neuronal voltage-gated sodium channel alpha 1 subunit, cause SMEI, GEFS+, and related epileptic syndromes. We herein report the R1575C-SCN1A mutation identified in a patient with Rasmussen encephalitis. R1575C were constructed in a recombinant human SCN1A and then heterologously expressed in HEK293 cells along with the human beta 1 and beta 2 sodium channel accessory subunits. Whole-cell patch-clamp recording was used to define biophysical properties. The R1575C channels exhibited increased channel availability and an increased persistent sodium current in comparison to the wild-type. These defects of electrophysiological properties can result in neuronal hyperexitability. The seizure susceptibility allele may influence the pathogenesis of Rasmussen encephalitis in this case.

DOI： 10.1111/j.1528-1167.2007.01411.x

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER  

Bionanocapsules (BNCs) are hollow nanoparticles that are composed of L protein (the hepatitis B virus surface antigen) and show specific affinity for human hepatocytes. The pre-S1 peptide displayed on the surface of BNCs is the specific ligand for binding to the receptor on human hepatocytes. Therefore, BNCs are not delivered to other tissues, such as the brain. The aim of the present study was to develop a novel drug delivery system (DIDS) targeting brain tumors using BNCs that selectively targeted brain tumors. Epidermal growth factor receptor (EGFR), especially a constitutively active genomic sequence deletion variant of EGFR (EGFRvIII), is overexpressed in human glioblastoma. In the present study, we replaced the pre-S1 peptide with the antibody affinity motif of protein A and made hybrid BNCs conjugated with anti-human EGFR antibody recognizing EGFRvIII. The hybrid BNCs were efficiently delivered to glioma cells but not normal glial cells. Moreover, we confirmed the specific delivery of the hybrid BNCs to brain tumors in an in vivo brain tumor model. These results suggest that this new approach using BNCs is a promising system for brain tumor-targeted drug delivery. (C) 2007 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.jconrel.2007.06.019

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：PHYSIOLOGICAL SOC JAPAN  

Exendin-4 (Ex4) is a peptide found in the lizard Heloderma suspectum, and it has a high similarity to glucagon-like peptide 1 (GLP-1). It induces insulin secretion without the risk of hypoglycemic episodes. Cyclin-dependent kinase 5 (Cdk5) is a serine/threonine kinase that is predominantly expressed in neurons. Recent studies have shown that this kinase regulates glucose-stimulated insulin secretion. Cdk5 inhibition enhances insulin secretion under conditions of stimulation by high glucose, but not low glucose. In the present study, we examined whether R-roscovitine (R-ros), a Cdk5 inhibitor, enhances insulin secretion induced by Ex4. R-ros induced Ex4-dependent insulin secretion under conditions of high glucose, but not low glucose in MIN6B1 cells. The enhancement by R-ros was also observed in db/db mice, a mouse model of type 2 diabetes. Moreover, long-term treatment with Ex4 and R-ros significantly improved HbA1c compared with treatment using only Ex4. These results suggest that a co-application of R-ros and Ex4 may become a promising therapy for the treatment of type 2 diabetes.

DOI： 10.2170/physiolsci.RP006607

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：NATURE PUBLISHING GROUP  

Under normal physiological conditions, synaptic vesicle endocytosis is regulated by phosphorylation and Ca2+-dependent dephosphorylation of endocytic proteins such as amphiphysin and dynamin. To investigate the regulatory mechanisms that may occur under the conditions of excessive presynaptic Ca2+ influx observed preceding neural hyperexcitation, we examined hippocampal slices following high-potassium or high-frequency electrical stimulation (HFS). In both cases, three truncated forms of amphiphysin I resulted from cleavage by the protease calpain. In vitro, the binding of truncated amphiphysin I to dynamin I and copolymerization into rings with dynamin I were inhibited, but its interaction with liposomes was not affected. Moreover, overexpression of the truncated form of amphiphysin I inhibited endocytosis of transferrin and synaptic vesicles. Inhibiting calpain prevented HFS-induced depression of presynaptic transmission. Finally, calpain-dependent amphiphysin I cleavage attenuated kainate-induced seizures. These results suggest that calpain-dependent cleavage of amphiphysin I inhibits synaptic vesicle endocytosis during neural hyperexcitation and demonstrate a novel post-translational regulation of endocytosis.

DOI： 10.1038/sj.emboj.7601741

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Language：Japanese   Publisher：(一社)日本小児神経学会  

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Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：BLACKWELL PUBLISHING  

Purpose: Mutations in SCN1A, encoding the human Na(V)1.1 neuronal voltage-gated sodium channel, cause the syndrome of severe myoclonic epilepsy of infancy (SMEI). Most SMEI-associated mutations are predicted to truncate the SCN1A protein, likely causing a loss of sodium channel function. However, many missense or in-frame deletion SCN1A mutations have also been reported in this disorder, but their functional impact is largely unknown. Here we report the functional characterization of eight SCN1A mutations (G177E, I227S, R393H, Y426N, H939Q, C959R, delF1289, and T1909I) previously identified in SMEI probands.
Methods: SCN1A mutants were constructed in a recombinant human SCN1A and then heterologously expressed in human tsA201 cells along with the human beta(1) and beta(2) sodium channel accessory subunits. Whole-cell patch-clamp recording was used to define biophysical properties of each mutant and for comparison with the wild-type (WT) channel.
Results: Six of the mutants were nonfunctional, but Y426N and T1909I generated measurable sodium channel activity. Cells expressing Y426N and T1909I had significantly lower current densities compared with WT-SCN1A. In addition, other biophysical abnormalities were observed for the two functional mutants including decreased channel availability (Y426N) and increased persistent sodium current (T1909I).
Conclusions: We conclude that SMEI is caused either by complete loss of SCN1A function, or by dysfunctional sodium channels exhibiting mixed biophysical properties. This wide spectrum of functional defects observed among SCN1A mutations suggests that SMEI may result from more than a single molecular or cellular mechanism, or require other factors for pathogenesis.

DOI： 10.1111/j.1528-1167.2006.00643.x

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Mutations in SCN1A, the gene encoding the brain voltage-gated sodium channel alpha(1) subunit (Na(V)1.1), are associated with genetic forms of epilepsy, including generalized epilepsy with febrile seizures plus (GEFS+ type 2), severe myoclonic epilepsy of infancy (SMEI) and related conditions. Several missense SCN1A mutations have been identified in probands affected by the syndrome of intractable childhood epilepsy with generalized tonic-clonic seizures (ICEGTC), which bears similarity to SMEI. To test whether ICEGTC arises from molecular mechanisms similar to those involved in SMEI, we characterized eight ICEGTC missense mutations by whole-cell patch clamp recording of recombinant human SCN1A heterologously expressed in cultured mammalian cells. Two mutations (G979R and T1709I) were non-functional. The remaining alleles (T808S, V983A, N1011I, V1611F, P1632S and F1808L) exhibited measurable sodium current, but had heterogeneous biophysical phenotypes. Mutant channels exhibited lower (V983A, N1011I and F1808L), greater (T808S) or similar (V1611F and P1632S) peak sodium current densities compared with wild-type (WT) SCN1A. Three mutations (V1611F, P1632S and F1808L) displayed hyperpolarized conductance-voltage relationships, while V983A exhibited a strong depolarizing shift in the voltage dependence of activation. All mutants except T808S had hyperpolarized shifts in the voltage dependence of steady-state channel availability. Three mutants (V1611F, P1632S and F1808L) exhibited persistent sodium current ranging from similar to 1-3% of peak current amplitude that was significantly greater than WT-SCN1A. Several mutants had impaired slow inactivation, with V983A showing the most prominent effect. Finally, all of the functional alleles exhibited reduced use-dependent channel inhibition. In summary, SCN1A mutations associated with ICEGTC result in a wide spectrum of biophysical defects, including mild-to-moderate gating impairments, shifted voltage dependence and reduced use dependence. The constellation of biophysical abnormalities for some mutants is distinct from those previously observed for GEFS+ and SMEI, suggesting possible, but complex, genotype-phenotype correlations.

DOI： 10.1113/jphysiol.2005.094326

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Absence seizures are classified into typical and atypical absences according to clinical and EEG characteristics. Although missense mutations in the GABA(A) receptor gamma 2 subunits (GABRG2) gene have recently been detected in two families with typical absence seizures, no study has been carried out to clarify the relationship between atypical absence and GABA(A) receptors. We performed mutation analysis of all the coding exons of GABA(A) receptor alpha 1, beta 2 and gamma 2 subunit (GABRA1, GABRB2 and GABRG2) genes by direct sequencing to clarify whether there was common molecular biological mechanism underlying both typical and atypical absences. We recruited 52 unrelated Japanese patients, thirty-eight with typical absences and 14 with atypical absences. They consisted of 38 with childhood absence epilepsy, three with Lennox-Gastaut syndrome, two with epilepsy with myoclonic-astatic seizures and nine with epilepsy with continuous spike-waves during slow wave sleep. All of the subjects were idiopathic or cryptogenic cases without any organic brain lesions or underlying diseases. We detected five polymorphisms (T156C in GABRA1, C1194T in GABRB2, and C315T, T588C and C1230T in GABRG2), and they are silent mutations. In conclusion, mutations in GABRA1, GABRB2 and GABRG2 do not seem to be a major genetic cause of epilepsy with typical and atypical absences in Japanese subjects. (c) 2005 Elsevier Ireland Ltd. All fights reserved.

DOI： 10.1016/j.neulet.2005.04.017

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A total of 45 different mutations of methyl-CpG-binding protein 2 gene (MECP2) were identified in 145 of 219 Japanese patients with typical or atypical Rett syndrome (RTT) (66.2%). A missense mutation, T158M was the most common mutation of MECP2, identified in 22 (19.1%) patients, followed by four nonsense mutations, R168X (14.8%), R270X (13.0%), R255X (9.6%), and R294X (6.1%) in 115 patients with classical RTT. Two missense mutations, R133C (33.3%) and R306C (23.3%), and a nonsense mutation, R294X (13.3%), were common in 30 patients with atypical RTT, including the preserved speech variant (PSV). Frameshift mutations due to nucleotide deletion or insertion were identified in 22 patients with MECP2 mutations, and one of them had a 3.6 kb deletion encompassing exons 3 and 4. Three patients with classical RTT had a splicing anomaly. The wide spectrum of phenotypic variability in patients with RTT has been considered to be correlated with the mutation type and location in MECP2, and X-inactivation. However, most patients showed a random X-inactivation pattern evaluated by an androgen receptor gene polymorphism in this study, suggesting that a skewed X-inactivation might not be a main modification factor on clinical phenotypes of RTT. In addition, three new missense mutations, P176R, A378V and T479M, were identified in patients with RTT, but also in healthy Japanese, indicating that these mutations are non-pathogenic in Japanese. Information about rare polymorphic variations is very important for the molecular diagnosis of RTT, although rare polymorphic variants might differ among ethnic groups. (c) 2004 Elsevier B.V. All tights reserved.

DOI： 10.1016/j.braindev.2004.06.003

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To clarify the relationship between the degree of developmental disturbance and the severity of epilepsy in Angelman syndrome, we investigated 11 patients and measured both clinical outcomes and EEG parameters. Seven patients were followed up until after 8 years of age. Eight patients were found to have 15q11-q13 deletions.
All patients experienced epileptic seizures and all but one displayed nonconvulsive status epilepticus (NCSE) during the period of observation. Epileptic seizures, including NCSE, disappeared by around 8 years of age. In addition, specific epileptic discharges, as measured by EEG, tended to subside with age. Although development seemed almost normal or only slightly delayed during the first 6 months of life, all patients eventually developed severe retardation. Two patients displayed very severe retardation and were unable to comprehend language or walk independently at the last follow-up. Only one patient was able to speak a few meaningful words. In one of the most severely affected patients, who showed the earliest onset of seizures and NCSE, it is possible that the repetitive bouts of NCSE might be responsible for the severe developmental outcome. However, the other patient with particularly severe retardation did not experience NCSE, while the patient with the most favorable outcome had repetitive episodes of NCSE.
Therefore, we conclude that the severity of developmental disturbance in Angelman syndrome is not necessarily related to the degree of epilepsy. However, intensive therapy for NOSE might still be justified because there are some patients in whom NOSE results in a transient and sometimes permanent decline in mental and motor functioning.
(C) 2004 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.braindev.2003.09.015

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：BLACKWELL PUBLISHING INC  

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：W B SAUNDERS CO LTD  

We performed a longitudinal clinico-electroencephalographic study of 23 children who were diagnosed as having absence epilepsy on their initial visits to our facility and we analysed those factors which lead to an unfavourable prognosis. Subjects and methods: We divided the 23 patients into three groups according to their clinical courses: Group A: eight patients who responded well to the therapy and became seizure free without relapse of epileptic discharges on EEGs; Group B: thirteen patients who suffered from relapse of epileptic discharges on EEGs despite clinical seizure cessation; Group C: two patients who continued to suffer from seizures. Results: (1) Fifty-six percent of all patients had focal epileptic discharges, including a surprising 63% of patients in Group A. (2) 'Lead in' in the ictal EEGs and automatisms during seizures were most commonly observed in patients in Group B, although there were no significant differences between the three groups. (3) The epilepsy of one patient in Group C evolved into complex partial seizures or absence status during her clinical course. She seemed to suffer from so-called 'frontal absence', despite the fact that her initial EEG did not show any focal abnormalities. (4) Patients in Group B were treated with tower AED dosages than those in Group A. In addition, one patient in Group C was treated irregularly. Conclusion: We conclude that it is not uncommon for patients with absence epilepsy to show focal abnormalities on EEGs and clinical ictal automatisms. Thus, the existence of clinical ictal automatisms and focal signs in electroencephalographic features are not sufficient indicators of the final outcome. Furthermore, it appears that regular and adequate drug therapy is important for a favourable prognosis. (C) 2003 BEA Trading Ltd. Published by Elsevier Ltd. All rights reserved.

DOI： 10.1016/S1059-1311(03)00196-1

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Objectives: Febrile seizures plus (FS +) are attracting attention for their corresponding genetic abnormalities, and are defined as febrile seizures (FS) continuing beyond 6 years of age (late FS) or those associated with afebrile seizures. We tried to elucidate their clinical and EEG characteristics as compared with those of children having only FS. Subjects and methods: We reviewed clinical records in a pediatric neurology clinic to identify 31 patients with FS + (group FS +) and 51 with only FS (group FS). Their family history of seizures, clinical features and EEG findings were compared. Results: A family history of seizures was noted in 14 patients (45.2%) of group FS + and in 24 (47.1%) of group FS. In group FS +, 19 patients had late FS, 11 had afebrile seizures, and the remaining one had both types of seizures. Two patients had seizures induced by TV/video-game as well, and another suffered from absences. Epileptic EEG abnormalities, which included diffuse spike-waves and focal spikes, were noted in 13 patients (41.9%) of group FS + and 12 (23.5%) of group FS. Conclusions: The clinical and EEG characteristics of the children having FS + were diverse, without significant differences from those with FS except for the seizures types. (C) 2003 Elsevier B.V. All rights reserved.

DOI： 10.1016/S0387-7604(03)00134-7

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：WILEY-BLACKWELL  

Purpose: A retrospective study was carried out on 53 cases with childhood epilepsy to evaluate the validity of the initial selection of antiepileptic drug (AED).
Methods: We investigated the AEDs selected at the beginning of the treatment from the medical records of 53 untreated cases. A follow-up study was undertaken to evaluate the effects of the AEDs. In the second study, we investigated the AEDs of 10 cases with atypical benign partial epilepsy (ABPE), to clarify whether the initial AEDs selected for rolandic epilepsy were related to the appearance of ABPE.
Results: The AEDs used at the initial stage consisted of carbamazepine (CBZ), valproic acid (VPA), phenobarbital (PB), and vitamin B-6. The main AEDs were CBZ and VPA for localization-related epilepsy, and VPA for generalized epilepsy. The initial selection of AEDs in 41 (85.4%) of 48 cases treated with AEDs were considered to be correct from the results of follow-up. We could not specify any AEDs that related to the appearance of ABPE.
Conclusions: The selection of AED in this series was considered to be most appropriate. We proposed a criterion to determine whether to begin the AED treatment immediately at the initial seizure.

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Authorship：Lead author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

We classified 28 patients with severe myoclonic epilepsy in infancy (SME) according to the presence or absence of myoclonic seizures and/or atypical absences. Eleven of the patients had myoclonic seizures and/or atypical absences, and we refer to this condition as 'typical SME (TSME)'. Seventeen of the patients had only segmental myoclonias, and we refer to this condition as 'borderline SME (BSME)'. We then analyzed the electroclinical and genetic characteristics of these two groups. Ten of the 11 TSME patients had a photoparoxysmal response at some time during their clinical course, while none of the BSME patients showed this response. TSME and BSME showed a significant difference in regard to gender ratio: female dominance in TSME and male dominance in BSME (P = 0.008). The detection rate of the voltage-gated sodium channel alpha1-subunit (SCN1A) gene mutations was 72.7 and 88.2% in TSME and BSME, respectively. There was no difference in the type or rate of mutation between TSME and BSME. We conclude that TSME and BSME show distinct differences in photoparoxysmal response and gender, which might be caused by some genetic mechanism(s) other than the SCN1A gene mutation. (C) 2003 Elsevier Science B.V. All rights reserved.

DOI： 10.1016/S0387-7604(03)00038-X

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We report on the electroclinical findings and the results of a molecular genetic study of a patient with typical severe myoclonic epilepsy ill infancy (TSME) and three with borderline SME (BSME) who showed paroxysmal movement disorders, such as choreoathetosis, dystonia and ballismus, during their clinical course. BSME was defined as a clinical entity that shares common characteristics with TSME but lacks myoclonic seizures associated with ictal EEG changes. When the paroxysmal movement disorders were first observed, all the patients in this study were being treated with polytherapy including phenytoin (PHT), and these abnormal movements disappeared when PHT was discontinued or reduced. However, on other occasions, two of our cases also showed the same abnormal movements even when not being treated with PHT. One patient with TSME and two of the three patients with BSME had SCN1A gene mutations that lead to truncation of the associated protein. We conclude that paroxysmal movement disorders seen in SME patients were closely related to their AED therapy, especially the use of PHT. It is thought that patients with both TSME and BSME have some predisposition toward paroxysmal movement disorders, and that this predisposition is partly related to sodium channel dysfunction, although some other factors might influence the occurrence of this phenomenon. (C) 2003 Elsevier Science B.V. All rights reserved.

DOI： 10.1016/S0387-7604(03)00025-1

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Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：ACADEMIC PRESS INC ELSEVIER SCIENCE  

To investigate the possible correlation between genotype and phenotype of epilepsy, we analyzed the voltage-gated sodium channel alpha1-subunit (SCNIA) gene, beta1-subunit (SCN1B) gene, and gamma-aminobutyric acidA receptor gamma2-subunit (GABRG2) gene in DNAs from peripheral blood cells of 29 patients with severe myoclonic epilepsy in infancy (SME) and 11 patients with other types of epilepsy. Mutations of the SCNIA gene were detected in 24 of the 29 patients (82.7%) with SME, although none with other types of epilepsy. The mutations included deletion, insertion, missense, and nonsense mutations. We could not find any mutations of the SCN1B and GABRG2 genes in all patients. Our data suggested that the SCNIA mutations were significantly correlated with SME (p &lt; .0001). As we could not find SCNIA mutations in their parents, one of critical causes of SME may be de novo mutation of the SCNIA gene occurred in the course of meiosis in the parents. (C) 2002 Elsevier Science (USA). All rights reserved.

DOI： 10.1016/S0006-291X(02)00617-4

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：GEORG THIEME VERLAG KG  

Purpose: To clarify the relationship between paroxysmal kinesigenic choreoathetosis (PKC) and epilepsy, we investigated the clinical and electroencephalographic (EEG) findings of patients with familial PKC and epilepsy, as well as sporadic cases with both PKC and epilepsy.
Patients and Methods: Patients consisted of 12 familial cases from seven families and three sporadic cases. The period of follow-up ranged from 17 months to 33 years, 7 months (average: 16 years, 8 months). During the follow-up, a total of 163 EEGs (11 EEGs per subject) were studied, including interictal and ictal EEGs.
Results: Transient epileptic discharges were found in ten of the 15 patients (66.7%) during the clinical course. As for focus, centro-midtemporal and frontal spikes were most often observed. The ictal EEG of an afebrile convulsion in one patient showed a partial seizure with secondary generalization which originated from the frontal area.
Conclusions: It appears that patients who suffer from both PKC and epilepsy have a functional abnormality of the cerebral cortex, particularly in the perirolandic and frontal regions.

DOI： 10.1055/s-2002-23594

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Authorship：Lead author   Language：Japanese  

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

It is important for the fields of child neurology and child public health to clarify the prevalence and incidence rates of West syndrome because this syndrome is a major cause of developmental disorders.
However, there have been few reports in Japan on the prevalence rate of West syndrome in the general population.
We carried out a population-based survey in Okayama Prefecture, in western Japan in 1994. The Population under 2 years of age in Okayama Prefecture in 1994 was 37,085. Six cases of West syndrome were identified. The prevalence rate was 0.16 per 1000. (C) 2001 Elsevier Science BN. All rights reserved.

DOI： 10.1016/S0387-7604(01)00273-X

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：GEORG THIEME VERLAG KG  

sThe spectrum of clinico-electrical characteristics of epileptic spasms associated with cortical malformation was studied in detail. The subjects were 15 patients suffering from spasms and cortical malformation demonstrated by MRI. The types of cortical malformation causing spasms were various, including hemimegalencephaly, diffuse pachygyria, focal cortical dysplasia, and polymicrogyria. Ohtahara syndrome was diagnosed in 3 patients, and West syndrome in 8. Symptomatic localization-related epilepsy preceded West syndrome in 4 patients, and a transition from Ohtahara syndrome to West syndrome was observed in one. West syndrome was followed by symptomatic generalized epilepsy including Lennox-Gastaut syndrome in 4 patients. Nine patients showed a condition which was labeled "epilepsy with partial seizures and spasms" (EPS) and characterized by the coexistence of partial seizures and spasms, and multifocal epileptic discharges on EEG. Spasms occurred only as EPS in 5 patients. EPS appeared following Ohtahara syndrome or West syndrome in 4 patients, and showed a transition to symptomatic localization-related epilepsy in 4. However, EPS did not evolve into generalized epilepsy, and persisted until the time of last follow-up in 5 patients. Therefore, the clinico-electrical pictures of patients with spasms and cortical malformation were diverse and not always limited within those of typical generalized epilepsy.

DOI： 10.1055/s-2001-19117

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Authorship：Lead author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：LIPPINCOTT WILLIAMS & WILKINS  

Purpose: To investigate the significance of cortical pathology of tonic spasms in patients with tuberous sclerosis.
Methods: The subjects were 38 patients with epilepsy associated with tuberous sclerosis. We analyzed ictal EEGs of tonic spasms and partial seizures by means of video-EEG monitoring for a total of 763 tonic spasms in 20 patients and 107 partial seizures in 15 patients. We also investigated the relation between partial seizures and magnetic resonance imaging (MRI) findings of these patients.
Results: Ictal EEG patterns of tonic spasms were divided into generalized and focal patterns. Thirteen patients had only generalized patterns, whereas seven had both patterns. In five patients who had focal ictal patterns of tonic spasms and partial seizures, the location of focal patterns corresponded with the location of onset of partial seizures. Focal discharges were seen immediately before, after, and in the middle of tonic spasms in series in 13 patients. The location of focal discharges also corresponded with the location of the onset of partial seizures in 10 of the 13 patients. Regarding partial seizures, four patients had multiple active epileptogenic foci during the same period, and two others had shifting epileptogenic foci with increasing age.
Conclusions: These findings indicate that cortical pathology plays an important role in the occurrence not only of partial seizures but also of tonic spasms in patients with tuberous sclerosis.

DOI： 10.1111/j.1528-1157.1998.tb01325.x

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：LIPPINCOTT WILLIAMS & WILKINS  

Purpose: To study the clinical and electroencephalographic (EEG) characteristics of patients whose epilepsy is associated with tuberous sclerosis, with special reference to their clinical course.
Methods: We investigated the electroclinical and radiologic features of 38 patients with epilepsy associated with tuberous sclerosis.
Results: Eleven patients showed only generalized epilepsy, and 10 showed only localization-related epilepsy throughout their clinical course. Among the other 17 cases, the nature of the epilepsy changed between generalized and localization-related epilepsies during the clinical course. A shift from generalized to localization-related epilepsies was more common than the reverse. Seventeen had West syndrome (WS), three had Lennox-Gastaut syndrome (LGS), and eight had epilepsies that evolved from WS to LGS. Tonic spasms, mostly in series, were seen in all 28 patients with generalized epilepsy. Eleven of the 28 patients had partial seizures and tonic spasms in the same period. Six of them showed "simultaneous seizures," consisting of tonic spasms in series and a partial seizure. Partial seizures were the main seizure type in 27 patients with localization-related epilepsy, but three of them also showed tonic spasms that included "simultaneous seizures." Ictal EEGs revealed multiple active foci in the same period that could shift during the clinical course. Neither the location nor number of tubers was related to the clinical course. As for seizure outcome, 12 (32%) of 38 patients were free from seizures at follow-up.
Conclusions: In epilepsies associated with tuberous sclerosis, there may be an interrelation between generalized and localization-related epilepsies, as well as one between generalized and partial seizures.

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Authorship：Lead author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE INC  

To clarify the characteristics of localization-related epilepsies in early infancy, we performed an electroclinical study of 28 epileptic patients whose first seizures occurred before 6 months of age. The patients were retrospectively divided into two groups: the seizure-controlled group (8 patients) and the refractory group (20 patients). The seizure-controlled group included the patients whose seizures were suppressed within 1 year after onset; the refractory group included all other patients. The characteristics of the refractory group were as follows: (1) most patients had serious underlying pathologies; (2) the seizure type in most cases was simple partial seizure or complex partial seizure without secondary generalization; (3) the interictal EEG showed focal abnormalities and severe dysrhythmia on the basic pattern associated with multifocal spikes in most cases; and (4) in some patients, West syndrome developed after localization- related epilepsies and generalized seizures appeared later in some cases. (C) 1997 by Elsevier Science Inc.

DOI： 10.1016/S0887-8994(96)00296-2

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We have produced a method to estimate ictal localized epileptic activity hidden among the background in scalp EEGs. When the visually completely different waveforms of the epileptic and background activities are nearly orthogonal, epileptic activity may be approximately extracted from the EEG data matrix by singular value decomposition with subsequent orthogonal rotation to match the distribution of one component with that of the epileptic source. A simulation study was carried out using a matrix mimicking the scalp EEG with an inconspicuous ictal epileptic activity from a dipole source. This hidden epileptic activity was approximately recovered by matching the dipole of interest with the epileptic dipole, even when the simulated waveforms of the epileptic and background activities were not exactly orthogonal. High linear correlation between these two types of waveforms hampered the recovery of the epileptic activity. In another simulation study employing two epileptic dipoles producing activities with the same waveform and a brief time lag, it was indicated that the temporal relationship between the epileptic activities could be also estimated using the cross-correlation function. In the preliminary clinical application of this method to the ictal EEGs of complex partial seizures, rhythmic activities with seemingly epileptic waveforms were estimated at the dipoles which were located in the vicinity of cortical lesions revealed by neuroimaging studies. These activities were indicated to appear before any change in the scalp EEG. We hope for the clinical application of this method for noninvasive estimation of inconspicuous ictal epileptic activity.

DOI： 10.1007/BF01200712

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Language：English   Publisher：(一社)日本てんかん学会  

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DOI： 10.1016/j.neures.2011.07.592

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DOI： 10.1016/j.neures.2011.07.1372

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DOI： 10.1016/j.neures.2011.07.1284

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DOI： 10.1016/j.neures.2011.07.1317

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DOI： 10.1016/j.neures.2011.07.1293

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Language：English   Publisher：日本神経化学会  

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DOI： 10.1016/j.neures.2010.07.1007

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DOI： 10.1016/j.neures.2010.07.1398

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Language：English   Publishing type：Research paper, summary (international conference)   Publisher：SPRINGER TOKYO  

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Language：Japanese   Publisher：岡山医学会  

Dravet症候群患者に認められたカルシウムチャネル機能異常を引き起こすCACNB4遺伝子変異について検討した。SCN1A遺伝子解析で変異を認めたDravet症候群患者38例を対象とした。健常者200例を対照とした。Dravet症候群患者で、SCN1B遺伝子とGABRG2遺伝子に変異を持つ症例はなかったが、CACNB4遺伝子変異を持つ症例を1例見出した。全細胞記録では、R568X変異からは背景電流異常のナトリウム電流は認めなかった。変異チャネルが野生型に比し有意にBa2+電流が増大した。ピーク電圧、細胞キャパシタンス、電流密度も変異型が野生型よりも有意に高値であった。

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Language：Japanese   Publisher：(一社)日本生理学会  

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Language：English   Publishing type：Research paper, summary (international conference)   Publisher：SPRINGER TOKYO  

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Language：English   Publishing type：Research paper, summary (international conference)   Publisher：SPRINGER TOKYO  

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Language：English   Publishing type：Research paper, summary (international conference)   Publisher：ELSEVIER IRELAND LTD  

DOI： 10.1016/j.neures.2009.09.1444

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Language：Japanese   Publisher：Japan Epilepsy Society  

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Language：Japanese   Publisher：(一社)日本生理学会  

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Language：Japanese   Publisher：Japan Epilepsy Society  

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Language：Japanese   Publisher：(一社)日本生理学会  

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Language：English   Publishing type：Research paper, summary (international conference)   Publisher：ELSEVIER IRELAND LTD  

DOI： 10.1016/j.neures.2007.06.824

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Language：Japanese   Publisher：(一社)日本生理学会  

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Language：Japanese   Publisher：(一社)日本生理学会  

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Language：English   Publishing type：Research paper, summary (international conference)   Publisher：ELSEVIER IRELAND LTD  

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Language：English   Publishing type：Research paper, summary (international conference)   Publisher：ELSEVIER IRELAND LTD  

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Language：English   Publishing type：Research paper, summary (international conference)   Publisher：BLACKWELL PUBLISHING  

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Language：Japanese  

DOI： 10.11477/mf.1405100547

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Language：English   Publishing type：Research paper, summary (international conference)   Publisher：UNIV CHICAGO PRESS  

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Language：Japanese   Publisher：日本てんかん学会  

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Language：Japanese   Publisher：診断と治療社  

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Other Link： http://search.jamas.or.jp/link/ui/2004069174

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Language：English   Publishing type：Research paper, summary (international conference)   Publisher：UNIV CHICAGO PRESS  

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Language：Japanese   Publisher：日本てんかん学会  

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Language：Japanese  

Twenty-four patients with refractory epilepsy were treated with mexiletine as an additional antiepileptic drug. As the initial responses, seizures were decreased by 50% or more in 7 (46.7%) of 15 patients with symptomatic partial epilepsy (SPE), in none of 7 with symptomatic generalized-epilepsy (SGE), and in 1 of 2 with undetermined epilepsy. Seizures increased in 3 patients (20.0%) with SPE, and in 3 (42.9%) with SGE. Concerning seizure types, mexiletine had significant effects on 1 of 2 patients with simple partial seizures, on 7 of 13 with complex partial seizures, on 1 of 5 with secondarily generalized seizures, and on 1 of 8 with tonic seizures. No patients with a myoclonic seizure or atypical absence improved. Exacerbation of the seizures was observed in 2 of 13 patients with complex partial seizures, in 1 of 5 with secondarily generalized seizures, in 3 of 8 with tonic seizures, and in 2 of 3 with myoclonic seizures. Partial seizures were controlled well, whereas generalized seizures sometimes worsened. EEG improved in 3 patients with SPE
decrease of focal spikes in 2 patients and disappearance of secondary generalization in 1. Follow-up for more than 3 months showed seizures to be lessened in 2 patients. Mexiletine is useful for the treatment of refractory epilepsies, especially SPE.

DOI： 10.11251/ojjscn1969.32.29

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Language：Japanese   Publisher：日本てんかん学会  

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Language：Japanese   Publisher：日本てんかん学会  

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Language：English   Publishing type：Research paper, summary (international conference)   Publisher：LIPPINCOTT WILLIAMS & WILKINS  

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Language：English   Publishing type：Research paper, summary (international conference)   Publisher：LIPPINCOTT WILLIAMS & WILKINS  

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Language：Japanese   Publisher：日本てんかん学会  

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Language：Japanese   Publisher：岡山大学  

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Language：Japanese  

DOI： 10.4044/joma1947.107.7-8_99

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Language：English   Publishing type：Research paper, summary (international conference)   Publisher：LIPPINCOTT-RAVEN PUBL  

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Language：Japanese   Publisher：日本てんかん学会  

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Language：Japanese   Presentation type：Symposium, workshop panel (nominated)  

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Applicant：国立大学法人 岡山大学

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