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Find video protocols related to scientific articles indexed in Pubmed.
Modulation of the age at onset in spinocerebellar ataxia by CAG tracts in various genes.
Brain
PUBLISHED: 06-26-2014
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Polyglutamine-coding (CAG)n repeat expansions in seven different genes cause spinocerebellar ataxias. Although the size of the expansion is negatively correlated with age at onset, it accounts for only 50-70% of its variability. To find other factors involved in this variability, we performed a regression analysis in 1255 affected individuals with identified expansions (spinocerebellar ataxia types 1, 2, 3, 6 and 7), recruited through the European Consortium on Spinocerebellar Ataxias, to determine whether age at onset is influenced by the size of the normal allele in eight causal (CAG)n-containing genes (ATXN1-3, 6-7, 17, ATN1 and HTT). We confirmed the negative effect of the expanded allele and detected threshold effects reflected by a quadratic association between age at onset and CAG size in spinocerebellar ataxia types 1, 3 and 6. We also evidenced an interaction between the expanded and normal alleles in trans in individuals with spinocerebellar ataxia types 1, 6 and 7. Except for individuals with spinocerebellar ataxia type 1, age at onset was also influenced by other (CAG)n-containing genes: ATXN7 in spinocerebellar ataxia type 2; ATXN2, ATN1 and HTT in spinocerebellar ataxia type 3; ATXN1 and ATXN3 in spinocerebellar ataxia type 6; and ATXN3 and TBP in spinocerebellar ataxia type 7. This suggests that there are biological relationships among these genes. The results were partially replicated in four independent populations representing 460 Caucasians and 216 Asian samples; the differences are possibly explained by ethnic or geographical differences. As the variability in age at onset is not completely explained by the effects of the causative and modifier sister genes, other genetic or environmental factors must also play a role in these diseases.
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Relationship between serum reactive oxidative metabolite level and skin reaction in an irradiated rat model.
Free Radic. Res.
PUBLISHED: 03-17-2014
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Ionizing radiation generates free radicals and reactive oxygen species that induce DNA damage in vivo. This study aimed to determine the relationship between serum reactive oxygen metabolite (ROM) levels and skin reaction after irradiation in a rat model.
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Autosomal-recessive complicated spastic paraplegia with a novel lysosomal trafficking regulator gene mutation.
J. Neurol. Neurosurg. Psychiatr.
PUBLISHED: 02-12-2014
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Autosomal-recessive hereditary spastic paraplegias (AR-HSP) consist of a genetically diverse group of neurodegenerative diseases characterised by pyramidal tracts dysfunction. The causative genes for many types of AR-HSP remain elusive. We tried to identify the gene mutation for AR-HSP with cerebellar ataxia and neuropathy.
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Molecular epidemiology and clinical spectrum of hereditary spastic paraplegia in the Japanese population based on comprehensive mutational analyses.
J. Hum. Genet.
PUBLISHED: 01-23-2014
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Hereditary spastic paraplegia (HSP) is one of the most genetically heterogeneous neurodegenerative disorders characterized by progressive spasticity and pyramidal weakness of lower limbs. Because >30 causative genes have been identified, screening of multiple genes is required for establishing molecular diagnosis of individual patients with HSP. To elucidate molecular epidemiology of HSP in the Japanese population, we have conducted mutational analyses of 16 causative genes of HSP (L1CAM, PLP1, ATL1, SPAST, CYP7B1, NIPA1, SPG7, KIAA0196, KIF5A, HSPD1, BSCL2, SPG11, SPG20, SPG21, REEP1 and ZFYVE27) using resequencing microarrays, array-based comparative genomic hybridization and Sanger sequencing. The mutational analysis of 129 Japanese patients revealed 49 mutations in 46 patients, 32 of which were novel. Molecular diagnosis was accomplished for 67.3% (33/49) of autosomal dominant HSP patients. Even among sporadic HSP patients, mutations were identified in 11.1% (7/63) of them. The present study elucidated the molecular epidemiology of HSP in the Japanese population and further broadened the mutational and clinical spectra of HSP.
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Rapid detection of expanded short tandem repeats in personal genomics using hybrid sequencing.
Bioinformatics
PUBLISHED: 11-08-2013
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Long expansions of short tandem repeats (STRs), i.e. DNA repeats of 2-6 nt, are associated with some genetic diseases. Cost-efficient high-throughput sequencing can quickly produce billions of short reads that would be useful for uncovering disease-associated STRs. However, enumerating STRs in short reads remains largely unexplored because of the difficulty in elucidating STRs much longer than 100 bp, the typical length of short reads.
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Recurrent K3E mutation in Cu/Zn superoxide dismutase gene associated with amyotrophic lateral sclerosis.
Amyotroph Lateral Scler Frontotemporal Degener
PUBLISHED: 07-30-2013
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Cu/Zn superoxide dismutase (SOD1) gene mutations are the most frequently reported genetic causes of amyotrophic lateral sclerosis (ALS). The objective of the study was to describe a clinical phenotype and haplotype background of Polish and Japanese ALS patients harbouring the K3E SOD1 mutation. The K3E mutation was identified by direct sequencing, high resolution melting analysis or high-throughput microarray-based resequencing system. Microsatellite polymorphic markers flanking SOD1 were genotyped in members of six kindreds and two SALS patients. Results demonstrated that the K3E mutation was responsible for classic ALS. The median age of onset was 54 years. The clinical phenotype did not substantially differ between SALS and FALS cases of either ethnic origin, with some intrafamiliar variabilities. There was a limb onset in 92% of patients. In patients with bulbar syndrome, dysphagia predominated over dysarthria. Respiratory insufficiency was found in 61.1% of patients (19-84 months after the first symptoms onset). Median survival was 101 months with age of death ranging from 45 to 77 years. K3E was the most frequent SOD1 mutation among Polish FALS patients. It originated independently, on different haplotype background in the Polish and Japanese populations. In conclusion, recurrent K3E mutation results in a relatively slowly progressing limb onset ALS with classic phenotype.
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ERBB4 mutations that disrupt the neuregulin-ErbB4 pathway cause amyotrophic lateral sclerosis type 19.
Am. J. Hum. Genet.
PUBLISHED: 05-12-2013
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Amyotrophic lateral sclerosis (ALS) is a devastating neurological disorder characterized by the degeneration of motor neurons and typically results in death within 3-5 years from onset. Familial ALS (FALS) comprises 5%-10% of ALS cases, and the identification of genes associated with FALS is indispensable to elucidating the molecular pathogenesis. We identified a Japanese family affected by late-onset, autosomal-dominant ALS in which mutations in genes known to be associated with FALS were excluded. A whole- genome sequencing and parametric linkage analysis under the assumption of an autosomal-dominant mode of inheritance with incomplete penetrance revealed the mutation c.2780G>A (p. Arg927Gln) in ERBB4. An extensive mutational analysis revealed the same mutation in a Canadian individual with familial ALS and a de novo mutation, c.3823C>T (p. Arg1275Trp), in a Japanese simplex case. These amino acid substitutions involve amino acids highly conserved among species, are predicted as probably damaging, and are located within a tyrosine kinase domain (p. Arg927Gln) or a C-terminal domain (p. Arg1275Trp), both of which mediate essential functions of ErbB4 as a receptor tyrosine kinase. Functional analysis revealed that these mutations led to a reduced autophosphorylation of ErbB4 upon neuregulin-1 (NRG-1) stimulation. Clinical presentations of the individuals with mutations were characterized by the involvement of both upper and lower motor neurons, a lack of obvious cognitive dysfunction, and relatively slow progression. This study indicates that disruption of the neuregulin-ErbB4 pathway is involved in the pathogenesis of ALS and potentially paves the way for the development of innovative therapeutic strategies such using NRGs or their agonists to upregulate ErbB4 functions.
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Exome analysis reveals a Japanese family with spinocerebellar ataxia, autosomal recessive 1.
J. Neurol. Sci.
PUBLISHED: 04-17-2013
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Spinocerebellar ataxia autosomal recessive 1 (SCAR1/AOA2) is clinically characterized by an early-onset progressive cerebellar ataxia with axonal neuropathy, ocular motor apraxia, and elevation of serum alpha-fetoprotein level. The disorder is caused by mutations in senataxin (SETX) gene. Here, we report a Japanese SCAR1/AOA2 family with a homozygous nonsense mutation (p.Q1441X) of SETX that was identified by exome sequencing. The family was previously reported as early-onset ataxia of undetermined cause. The present study emphasized the role of whole exome-sequence analysis to establish the molecular diagnosis of neurodegenerative disease presenting with diverse clinical presentations.
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An open trial of long-term testosterone suppression in spinal and bulbar muscular atrophy.
Muscle Nerve
PUBLISHED: 03-20-2013
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We investigated the long-term effects of leuprorelin on leg-muscle strength in spinal and bulbar muscular atrophy (SBMA). We hypothesized that testosterone suppression by leuprorelin would prevent the progression of muscle weakness.
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[Home medical care center project for an aging society].
Gan To Kagaku Ryoho
PUBLISHED: 12-23-2011
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We have to create a new paradigm for home medical care system towards a historical increase of elderly population in Japan. Tokyo University and Chiba University have been collaborating to erect a home medical care support center in Kashiwa, Chiba prefecture. We have been constructing a support center as well as a home care doctor system, and also created a teaching course for GPs to learn a home care doctor activity. We have also been constructing a regional network system called IT Net in Chiba, which connects all the entire medical and care staff. We will expand this model in many places and to instruct medical students and residents there in the near future.
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Interactions of household composition and required care level with functional and cognitive status among disabled Japanese elderly living in a suburban apartment complex.
Geriatr Gerontol Int
PUBLISHED: 12-23-2011
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In the forthcoming super-aging society, the appropriate assessment of functional and cognitive conditions of disabled elderly people will become increasingly significant in providing care services. Care level and household composition would be key factors to assess function. There might also be an interaction between the two factors with the function. The present study examined the associations of household composition and care level with functional and cognitive status among the disabled elderly living in a suburban apartment complex with a high rate of aged residents (39% in 2009).
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[Therapeutic trial design issues for future disease-modifying therapy of multiple system atrophy].
Rinsho Shinkeigaku
PUBLISHED: 09-21-2011
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Multiple system atrophy (MSA) is an adult-onset, progressive neurodegenerative disorder which is clinically characterized by various combinations of cerebellar ataxia, Parkinsonism, autonomic dysfunction and pyramidal signs. MSA is known as a sporadic disease, however, multiplex families with MSA suggest a genetic predisposition to MSA. The advanced genome research will clarify the pathogenetic mechanisms of MSA, and the disease-modifying therapy of MSA may be available in the future. To clarify the natural history of MSA for the future therapeutic trials, and to elucidate the molecular pathogenetic mechanisms of MSA, JAMSAC (Japan MSA research consortium), a nationwide consortium, was established in 2003. In the view of the future therapeutic trial for MSA, it is essential to design appropriate end point, sample size, duration of the trial. And inclusion criteria are also important for effective therapeutic trial. We conducted a cross-sectional study on 225 MSA patients using unified multiple system atrophy rating scale (UMSARS). As inclusion criteria, we employed additional criteria based on specific MRI findings to recruit earlier stage patients. Sample size estimation from the longitudinal study suggested we need sensitive outcome measures beside UMSARS. JAMSAC is planning to a longitudinal study for natural history of MSA in Japan.
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Mechanistic basis of bell-shaped dependence of inositol 1,4,5-trisphosphate receptor gating on cytosolic calcium.
Proc. Natl. Acad. Sci. U.S.A.
PUBLISHED: 08-29-2011
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The inositol 1,4,5-trisphosphate (IP(3)) receptor (IP(3)R) is an intracellular Ca(2+) release channel, and its opening is controlled by IP(3) and Ca(2+). A single IP(3) binding site and multiple Ca(2+) binding sites exist on single subunits, but the precise nature of the interplay between these two ligands in regulating biphasic dependence of channel activity on cytosolic Ca(2+) is unknown. In this study, we visualized conformational changes in IP(3)R evoked by various concentrations of ligands by using the FRET between two fluorescent proteins fused to the N terminus of individual subunits. IP(3) and Ca(2+) have opposite effects on the FRET signal change, but the combined effect of these ligands is not a simple summative response. The bell-shaped Ca(2+) dependence of FRET efficiency was observed after the subtraction of the component corresponding to the FRET change evoked by Ca(2+) alone from the FRET changes evoked by both ligands together. A mutant IP(3)R containing a single amino acid substitution at K508, which is critical for IP(3) binding, did not exhibit this bell-shaped Ca(2+) dependence of the subtracted FRET efficiency. Mutation at E2100, which is known as a Ca(2+) sensor, resulted in ?10-fold reduction in the Ca(2+) dependence of the subtracted signal. These results suggest that the subtracted FRET signal reflects IP(3)R activity. We propose a five-state model, which implements a dual-ligand competition response without complex allosteric regulation of Ca(2+) binding affinity, as the mechanism underlying the IP(3)-dependent regulation of the bell-shaped relationship between the IP(3)R activity and cytosolic Ca(2+).
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Comprehensive mutational analysis of LRRK2 reveals variants supporting association with autosomal dominant Parkinsons disease.
J. Hum. Genet.
PUBLISHED: 07-28-2011
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Parkinsons disease (PD) is a neurodegenerative disorder characterized by neurodegeneration, most notably of dopaminergic neurons in the substantia nigra. To date, six causative genes have been identified including LRRK2, whose mutations are the most frequent in autosomal dominant PD (Ad-PD). We conducted a comprehensive mutational analysis of LRRK2 in 30 Ad-PD (11 Japanese and 19 Caucasian) families employing a DNA microarray-based resequencing system and direct nucleotide sequence analysis, and identified 23 variants including two known mutations, p.G2019S and p.I1371V, in three Caucasian families and one Caucasian family, respectively, a novel putative pathogenic mutation, p.N1221K, in one Japanese family, and a known nonsynonymous variant, p.G2385R, in two Japanese families. Detailed analysis of the frequency of p.G2385R among 100 Japanese Ad-PD, 73 sporadic PD (sPD) and 238 controls revealed that the frequency of the p.G2385R variant was significantly higher in Ad-PD than in controls (allele frequency, 9.0 vs 2.1%) (?(2)=16.32, P=5.34 × 10(-5)). The p.G2385R variant, however, did not show complete cosegregation with PD. In addition, the frequency of p.G2385R was also higher in sPD than in controls, although not significant (allele frequency, 3.4 vs 2.1%) (?(2)=0.76, P=0.38). These observations support the possibility that p.G2385R is associated with an increased risk of PD.
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Impaired hippocampal long-term potentiation and failure of learning in ?1,4-N-acetylgalactosaminyltransferase gene transgenic mice.
Glycobiology
PUBLISHED: 07-06-2011
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Gangliosides (sialic acid-containing glycosphingolipids) play important roles in many physiological functions, including synaptic plasticity in the hippocampus, which is considered as a cellular mechanism of learning and memory. In the present study, three types of synaptic plasticity, long-term potentiation (LTP), long-term depression (LTD) and reversal of LTP (depotentiation, DP), in the field excitatory post-synaptic potential in CA1 hippocampal neurons and learning behavior were examined in ?1,4-N-acetylgalactosaminyltransferase (?1,4 GalNAc-T; GM2/GD2 synthase) gene transgenic (TG) mice, which showed a marked decrease in b-pathway gangliosides (GQ1b, GT1b and GD1b) in the brain and isolated hippocampus compared with wild-type (WT) mice. The magnitude of the LTP induced by tetanus (100 pulses at 100 Hz) in TG mice was significantly smaller than that in control WT mice, whereas there was no difference in the magnitude of the LTD induced by three short trains of low-frequency stimulation (LFS) (200 pulses at 1 Hz) at 20 min intervals between the two groups of mice. The reduction in the LTP produced by delivering three trains of LFS (200 pulses at 1 Hz, 20 min intervals) was significantly greater in the TG mice than in the WT mice. Learning was impaired in the four-pellet taking test (4PTT) in TG mice, with no significant difference in daily activity or activity during the 4PTT between TG and WT mice. These results suggest that the overexpression of ?1,4 GalNAc-T resulted in altered synaptic plasticity of LTP and DP in hippocampal CA1 neurons and learning in the 4PTT, and this is attributable to the shift from b-pathway gangliosides to a-pathway gangliosides.
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Inositol 1,4,5-trisphosphate receptor-mediated calcium release in Purkinje cells: from molecular mechanism to behavior.
Cerebellum
PUBLISHED: 06-25-2011
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The inositol 1,4,5-trisphosphate (IP(3)) receptor is highly expressed in cerebellar Purkinje cells and mediates conspicuous calcium release from intracellular calcium stores. Receptor stimulation, such as through mGluR1, activates the G(q)-PLC pathway, which leads to IP(3)-induced calcium release and subsequent cellular responses, including cerebellar long-term depression in Purkinje cells. Recent studies have demonstrated the regulatory mechanisms of IP(3) receptor, revealing activation via IP(3) and Ca(2+), inactivation via high concentrations of Ca(2+), and modulation by various proteins that bind to the IP(3) receptor. Novel calcium imaging techniques and caged compounds provide analysis of calcium signals at the single spine level in relation to the induction of long-term depression. Genetically encoded indicators for calcium or IP(3) could provide alternate Ca(2+) or IP(3) imaging, in particular, for in vivo observations. IP(3)-induced calcium release participates in early development of dendritic branch formation, and loss-of-function mutations or hyper-activation could result various diseases. The IP(3) receptor plays a central role in calcium signaling in Purkinje cells, affecting a wide variety of cellular functions, including development, plasticity, maintenance of synaptic functions, and cerebellar motor control.
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Evaluating Japanese patients with the Marfan syndrome using high-throughput microarray-based mutational analysis of fibrillin-1 gene.
Am. J. Cardiol.
PUBLISHED: 04-26-2011
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Marfan syndrome (MS) is an inherited connective tissue disorder, and detailed evaluations of multiple organ systems are required for its diagnosis. Genetic testing of the disease-causing fibrillin-1 gene (FBN1) is also important in this diagnostic scheme. The aim of this study was to define the clinical characteristics of Japanese patients with MS and enable the efficient and accurate diagnosis of MS with mutational analysis using a high-throughput microarray-based resequencing system. Fifty-three Japanese probands were recruited, and their clinical characteristics were evaluated using the Ghent criteria. For mutational analysis, an oligonucleotide microarray was designed to interrogate FBN1, and the entire exon and exon-intron boundaries of FBN1 were sequenced. Clinical evaluation revealed more pulmonary phenotypes and fewer skeletal phenotypes in Japanese patients with MS compared to Caucasians. The microarray-based resequencing system detected 35 kinds of mutations, including 23 new mutations. The mutation detection rate for patients who fulfilled the Ghent criteria reached 71%. Of note, splicing mutations accounted for 19% of all mutations, which is more than previously reported. In conclusion, this comprehensive approach successfully detected clinical phenotypes of Japanese patients with MS and demonstrated the usefulness and feasibility of this microarray-based high-throughput resequencing system for mutational analysis of MS.
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Role of inositol 1, 4, 5-trisphosphate receptors in the postsynaptic expression of guinea pig hippocampal mossy fiber depotentiation.
Brain Res.
PUBLISHED: 02-24-2011
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Long-term potentiation (LTP) at hippocampal mossy fiber-CA3 pyramidal neuron synapses was induced in the field excitatory postsynaptic potential (EPSP) by the delivery of HFS (a tetanus of two trains of 100 pulses at 100 Hz with a 10s interval) and was reversed (depotentiated) by a train of LFS of 1000 pulses at 2 Hz applied 60 min later. This depotentiation was triggered by activation of inositol 1, 4, 5-trisphosphate receptors (IP3Rs) during HFS, which may increase the postsynaptic intracellular Ca(2+) concentration, leading to a cellular process responsible for modification of LTP expression at mossy fiber-CA3 synapses. Furthermore, we found that activation of IP3Rs or protein phosphatase during LFS was required for the reversal of LTP expressed at mossy fiber-CA3 synapses. These results suggest that, in hippocampal mossy fiber-CA3 neuron synapses, activation of IP3Rs by a preconditioning HFS results in modulation of IP3R activation and/or postsynaptic protein phosphorylation during a subsequent LFS, leading to a decrease in the field EPSP and the erasure of LTP.
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Posterior column ataxia with retinitis pigmentosa in a Japanese family with a novel mutation in FLVCR1.
Neurogenetics
PUBLISHED: 01-26-2011
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Posterior column ataxia with retinitis pigmentosa (PCARP) is an autosomal recessive neurodegenerative disorder characterized by retinitis pigmentosa and sensory ataxia. Previous studies of PCARP in two families showed a linkage to 1q31-q32. However, detailed investigations on the clinical presentations as well as molecular genetics of PCARP have been limited. Here, we describe a Japanese consanguineous family with PCARP. Two affected siblings suffered from childhood-onset retinitis pigmentosa and slowly progressive sensory ataxia. They also showed mild mental retardation, which has not been described in patients with PCARP. Parametric linkage analysis using high-density single nucleotide polymorphism arrays supported a linkage to the same locus. Target capture and high-throughput sequencing technologies revealed a novel homozygous c.1477G>C (G493R) mutation in FLVCR1, which cosegregated with the disease. A recent study has identified three independent mutations in FLVCR1 in the original and other families. Our results further confirmed that PCARP is caused by mutations in FLVCR1.
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Itraconazole-induced cholestasis: involvement of the inhibition of bile canalicular phospholipid translocator MDR3/ABCB4.
Mol. Pharmacol.
PUBLISHED: 11-05-2010
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Biliary secretion of bile acids and phospholipids, both of which are essential components of biliary micelles, are mediated by the bile salt export pump (BSEP/ABCB11) and multidrug resistance 3 P-glycoprotein (MDR3/ABCB4), respectively, and their genetic dysfunction leads to the acquisition of severe cholestatic diseases. In the present study, we found two patients with itraconazole (ITZ)-induced cholestatic liver injury with markedly high serum ITZ concentrations. To characterize the effect of ITZ on bile formation in vivo, biliary bile acids and phospholipids were analyzed in ITZ-treated rats, and it was revealed that biliary phospholipids, rather than bile acids, were drastically reduced in the presence of clinically relevant concentrations of ITZ. Moreover, by using MDR3-expressing LLC-PK1 cells, we found that MDR3-mediated efflux of [¹?C]phosphatidylcholine was significantly reduced by ITZ. In contrast, BSEP-mediated transport of [³H]taurocholate was not significantly affected by ITZ, which is consistent with our in vivo observations. In conclusion, this study suggests the involvement of the inhibition of MDR3-mediated biliary phospholipids secretion in ITZ-induced cholestasis. Our approach may be useful for analyzing mechanisms of drug-induced cholestasis and evaluating the cholestatic potential of clinically used drugs and drug candidates.
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A case of atypical amyloid polyneuropathy with predominant upper-limb involvement with the diagnosis unexpectedly found at lung operation.
Intern. Med.
PUBLISHED: 08-02-2010
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We present a patient of familial amyloid polyneuropathy (FAP) with predominant upper-limb involvement, the pattern of which resembled a mononeuropathy multiplex pattern. Sural nerve biopsy failed to diagnose the disorder, but lung partial resection performed later for other diagnostic purposes suggested FAP. A rare mutation in the transthyretin gene (S50R) was subsequently confirmed. Diagnostic challenges of FAP with atypical clinical presentations, including difficulties in pathological diagnosis, are discussed with a review of the literature.
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[Japan spastic paraplegia research consortium (JASPAC)].
Rinsho Shinkeigaku
PUBLISHED: 07-06-2010
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Japan Spastic Paraplegia Research Consortium (JASPAC), a nationwide clinical and genetic survey of patients with HSP in Japan, was started from 2006 as a project of the Research Committee for Ataxic Diseases of the Ministry of Health, Labor and Welfare, Japan. To date (October 4, 2010), 321 index patients with HSP have been registered from 40 prefectures in Japan. We are now performing molecular testing for the HSP patients using direct sequencing (SPG4, SPG31, and ARSACS), comparative genomic hybridization (CGH) array (SPG1/2/3A/4/5/6/7/8/10/11/13/15/17/20/21/31/33/39/42/ABCD1/alsin/SACS), and resequencing microarray (SPG1/2/3A/4/5/6/7/8/10/11/13/17/20/21/31/33/ABCD1). In 144 Japanese ADHSP families, SPG4 was the most common form, accounting for 47%, followed by SPG31 (4%), SPG3A (3%), SPG8 (1%), and SPG10 (1%). The results of molecular testing will be applicable to patients in terms of improved positive diagnosis, follow-up, and genetic counseling. Since approximately 40% of ADHSP remain unknown, we will perform high-throughput linkage analyses using SNP HiTLink (SNP High Throughput Linkage analysis system) for the identification of loci for disease-associated genes. Meanwhile, preliminary data showed that SPG11 and ARSACS were common in Japanese ARHSP families. JASPAC will contribute to elucidate the spectrum of clinical features and mutations, genotype/phenotype correlations, pathophisiology in various HSP phenotypes.
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A mutation database for amyotrophic lateral sclerosis.
Hum. Mutat.
PUBLISHED: 06-18-2010
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An amyotrophic lateral sclerosis (ALS) mutation database has been constructed as a publicly accessible online resource for recording the nucleotide and amino acid variants identified in genes associated with ALS, along with corresponding clinical conditions. The database currently consists of more than 600 entries, including about 180 unique variants found in 25 disease-causative or disease-related genes. In addition to published data collected from literature, novel variants identified by microarray resequencing in our laboratory are incorporated into the database. Every reported gene has a respective page that provides information on its variation positions with various statistics, clinical characteristics, and primary references, as well as gene-sequence and protein-structure information that will assist in assessing variation significance. Users can access a homology search function to find variations in arbitrary sequences of interest and to check if they have already been described in the database. This database is expected to fulfill an essential need in terms of integrating comprehensive information on genetic and clinical data related to ALS, which will subsequently deepen our understanding of the possible mechanisms of the disease, as well as help with the clinical practice and treatment of ALS. The database is accessible at: https://reseq.lifesciencedb.jp/resequence/SearchDisease.do?targetId=1. Data submission is open to all researchers and is highly encouraged.
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Multiplexed resequencing analysis to identify rare variants in pooled DNA with barcode indexing using next-generation sequencer.
J. Hum. Genet.
PUBLISHED: 05-20-2010
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We have recently found that multiple rare variants of the glucocerebrosidase gene (GBA) confer a robust risk for Parkinson disease, supporting the common disease-multiple rare variants hypothesis. To develop an efficient method of identifying rare variants in a large number of samples, we applied multiplexed resequencing using a next-generation sequencer to identification of rare variants of GBA. Sixteen sets of pooled DNAs from six pooled DNA samples were prepared. Each set of pooled DNAs was subjected to polymerase chain reaction to amplify the target gene (GBA) covering 6.5 kb, pooled into one tube with barcode indexing, and then subjected to extensive sequence analysis using the SOLiD System. Individual samples were also subjected to direct nucleotide sequence analysis. With the optimization of data processing, we were able to extract all the variants from 96 samples with acceptable rates of false-positive single-nucleotide variants.
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Identification of novel SNPs of ABCD1, ABCD2, ABCD3, and ABCD4 genes in patients with X-linked adrenoleukodystrophy (ALD) based on comprehensive resequencing and association studies with ALD phenotypes.
Neurogenetics
PUBLISHED: 05-15-2010
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Adrenoleukodystrophy (ALD) is an X-linked disorder affecting primarily the white matter of the central nervous system occasionally accompanied by adrenal insufficiency. Despite the discovery of the causative gene, ABCD1, no clear genotype-phenotype correlations have been established. Association studies based on single nucleotide polymorphisms (SNPs) identified by comprehensive resequencing of genes related to ABCD1 may reveal genes modifying ALD phenotypes. We analyzed 40 Japanese patients with ALD. ABCD1 and ABCD2 were analyzed using a newly developed microarray-based resequencing system. ABCD3 and ABCD4 were analyzed by direct nucleotide sequence analysis. Replication studies were conducted on an independent French ALD cohort with extreme phenotypes. All the mutations of ABCD1 were identified, and there was no correlation between the genotypes and phenotypes of ALD. SNPs identified by the comprehensive resequencing of ABCD2, ABCD3, and ABCD4 were used for association studies. There were no significant associations between these SNPs and ALD phenotypes, except for the five SNPs of ABCD4, which are in complete disequilibrium in the Japanese population. These five SNPs were significantly less frequently represented in patients with adrenomyeloneuropathy (AMN) than in controls in the Japanese population (p=0.0468), whereas there were no significant differences in patients with childhood cerebral ALD (CCALD). The replication study employing these five SNPs on an independent French ALD cohort, however, showed no significant associations with CCALD or pure AMN. This study showed that ABCD2, ABCD3, and ABCD4 are less likely the disease-modifying genes, necessitating further studies to identify genes modifying ALD phenotypes.
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Mechanisms of genomic instabilities underlying two common fragile-site-associated loci, PARK2 and DMD, in germ cell and cancer cell lines.
Am. J. Hum. Genet.
PUBLISHED: 03-23-2010
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Common fragile sites (CFSs) are specific chromosome regions that exhibit an increased frequency of breaks when cells are exposed to a DNA-replication inhibitor such as aphidicolin. PARK2 and DMD, the causative genes for autosomal-recessive juvenile Parkinsonism and Duchenne and Becker muscular dystrophy, respectively, are two very large genes that are located within aphidicolin-induced CFSs. Gross rearrangements within these two genes are frequently observed as the causative mutations for these diseases, and similar alterations within the large fragile sites that surround these genes are frequently observed in cancer cells. To elucidate the molecular mechanisms underlying this fragility, we performed a custom-designed high-density comparative genomic hybridization analysis to determine the junction sequences of approximately 500 breakpoints in germ cell lines and cancer cell lines involving PARK2 or DMD. The sequence signatures where these breakpoints occur share some similar features both in germ cell lines and in cancer cell lines. Detailed analyses of these structures revealed that microhomologies are predominantly involved in rearrangement processes. Furthermore, breakpoint-clustering regions coincide with the latest-replicating region and with large nuclear-lamina-associated domains and are flanked by the highest-flexibility peaks and R/G band boundaries, suggesting that factors affecting replication timing collectively contribute to the vulnerability for rearrangement in both germ cell and somatic cell lines.
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Changes in saliva interleukin-6 levels in patients with oral squamous cell carcinoma.
Oral Surg Oral Med Oral Pathol Oral Radiol Endod
PUBLISHED: 03-21-2010
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The aim of this study was to elucidate changes in interleukin-6 (IL-6) levels in whole saliva during the treatment of patients with oral squamous cell carcinoma (OSCC).
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Oral health care reduces the risk of postoperative surgical site infection in inpatients with oral squamous cell carcinoma.
Support Care Cancer
PUBLISHED: 02-23-2010
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Postoperative wound infection (WI) is a main complication after head and neck surgery. Poor oral health may be a risk factor for WI. We therefore assessed the contribution of oral health care in preventing postoperative WI in patients with oral squamous cell carcinoma (OSCC).
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TDP-43 M337V mutation in familial amyotrophic lateral sclerosis in Japan.
Intern. Med.
PUBLISHED: 02-15-2010
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The clinical features of a Japanese family with autosomal dominant adult-onset amyotrophic lateral sclerosis (ALS) are reported. Weakness initially affected the bulbar musculature, with later involvement of the extremities. Genetic studies failed to detect any mutations of the Cu/Zn superoxide dismutase-1 (SOD1) and Dynactin1 (DCTN1) genes, but revealed a single base pair change from wild-type adenine to guanine at position 1009 in TAR-DNA-binding protein (TDP-43), resulting in a methionine-to-valine substitution at position 337. The immunohistochemical study on autopsied brain of the probands aunt showed TDP-43-positive cytoplasmic inclusions in the anterior horn cells of the spinal cord and in the hypoglossal nucleus, as well as glial cytoplasmic inclusions in the precentral gyrus, suggesting that a neuroglial proteinopathy was related to TDP-43. In conclusion, a characteristic clinical phenotype of familial ALS with initial bulbar symptoms occurred in this family with TDP-43 M337V substitution, the pathomechanism of which should be elucidated.
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Synthesis of bisboron compounds and their strong inhibitory activity on store-operated calcium entry.
Bioorg. Med. Chem. Lett.
PUBLISHED: 01-11-2010
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Store-operated calcium entry (SOCE) is an important mechanism for replenishing intracellular calcium stores and for sustaining calcium signaling. We developed a method for synthesis of bisboron compounds that have two borinic acids or their esters in one molecule. These compounds are analogues of 2-APB, which is widely used as a membrane-permeable SOCE inhibitor. Further, we examined the effect of the newly synthesized bisboron compounds on SOCE in Jurkat T cells. All the bisboron compounds showed strong inhibitory activity on SOCE, with IC50 values of less than 1 microM, which were 20-45 times lower than observed with 2-APB.
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Potent transglutaminase inhibitors, aryl beta-aminoethyl ketones.
Bioorg. Med. Chem. Lett.
PUBLISHED: 10-20-2009
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Aryl beta-aminoethyl ketones were discovered as potent inhibitors of tissue transglutaminase. Heteroaryl-like thiophene groups and N-benzyl N-t-butyl aminoethyl group are critical to the strong inhibitory activity of aryl beta-aminoethyl ketones.
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Motor cortical epilepsia partialis continua in a patient with a localized sensory cortical lesion.
Clin Neurol Neurosurg
PUBLISHED: 06-17-2009
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We describe a 33-year-old man with cyclosporine encephalopathy who showed continuous jerking in the left upper limb due to epilepsia partialis continua. Jerk-locked back averaging (JLA) of magnetoencephalogram disclosed a spike preceding the jerk localized at the hand motor area, whereas JLA of electroencephalogram revealed no premyoclonus spikes. The paired-pulse motor cortical transcranial magnetic stimulation revealed motor cortical hyperexcitability, while the paired-pulse somatosensory evoked potential showed no sensory cortical hyperexcitability. The brain MRI showed a high intensity lesion localized at the hand sensory area. These results suggest that the jerks were produced by discharges at the motor cortex probably disinhibited by the sensory cortical lesion.
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[Neurodegenerative disease].
Nippon Rinsho
PUBLISHED: 06-11-2009
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Cloning of responsible genes for hereditary neurological diseases has been one of the most important fields in disease genome research since early days. To date, over two hundred genes for degenerative diseases have been identified. The accomplishment of the Human Genome Project and the development of DNA chip technology enabled man to conduct genome-wide association study(GWAS) of large scale sample sets, opening the way to elucidate genetic factors of sporadic diseases. Several results have been reported, including GWAS for amyotrophic lateral sclerosis and multiple sclerosis. Now new sequencing technology is emerging, which makes personal genome resequencing possible. Deep resequencing or personal genome would change revolutionarily the paradigm of genome research and medicine.
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Two novel 2-aminoethyl diphenylborinate (2-APB) analogues differentially activate and inhibit store-operated Ca(2+) entry via STIM proteins.
Cell Calcium
PUBLISHED: 05-27-2009
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Store-operated calcium entry (SOCE) or calcium release-activated calcium current (I(CRAC)) is a critical pathway to replenish intracellular calcium stores, and plays indispensable roles in cellular functions such as antigen-induced T lymphocyte activation. Despite the importance of I(CRAC) in cellular functions, lack of potent and specific inhibitor has limited the approaches to the function of I(CRAC) in native cells. 2-Aminoethyl diphenylborinate (2-APB) is a widely used SOCE/I(CRAC) inhibitor, while its effect is rather unspecific. In the attempt to develop more potent and selective compounds here we identified two structurally isomeric 2-APB analogues that are 100-fold more potent than 2-APB itself. One of the 2-APB analogues activates and inhibits endogenous SOCE depending on the concentration while the other only inhibits it. The 2-APB analogue inhibits store depletion-mediated STIM1 clustering as well as heterologously expressed CRAC current. Together with the observation that, unlike 2-APB, the analogue compounds failed to activate CRACM3/Orai3 current in the absence of STIM, our results suggest that inhibition and activation of SOCE/I(CRAC) by the 2-APB analogues is mediated by STIM.
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Mutations for Gaucher disease confer high susceptibility to Parkinson disease.
Arch. Neurol.
PUBLISHED: 05-13-2009
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Increased frequency of pathogenic variants in GBA, the causative gene for Gaucher disease, has been suggested to be associated with Parkinson disease (PD).
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Morphometric and functional correlation of human neuronal somata: pyramidal motor, special sensory and general sensory systems.
Okajimas Folia Anat Jpn
PUBLISHED: 05-05-2009
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Using an ideal tissue preparation method, we found a definite correlation between various human neuronal somata from the view point of accurate morphometry and functional evaluations. We believe this study may be of value, or even indispensable in the correct understanding of neurological symptomatology and phenomenology.
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Morphological evaluation of the human pyramidal tract: tapering of axons.
Okajimas Folia Anat Jpn
PUBLISHED: 05-05-2009
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It is generally accepted that nerve fiber conduction velocity is directly proportional to the fiber diameter under the condition, based on a supposition, that the transverse area of axons is normally maintained constant. Using an ideal preparation method for the purpose of axonal discrimination, we examined 43 human spinal cords after making transverse sections at the cervical, thoracic, lumbar and sacral levels and found a tapering of the axons in the lateral pyramidal tract, as the cross-sectional area of the pyramidal axons showed a definite decrease from the cervical to the sacral levels. Our results contradict the supposition that the transverse area of axons is normally maintained constant, which has for a long time been believed to be true without any evidence for it.
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SNP haplotype mapping in a small ALS family.
PLoS ONE
PUBLISHED: 04-27-2009
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The identification of genes for monogenic disorders has proven to be highly effective for understanding disease mechanisms, pathways and gene function in humans. Nevertheless, while thousands of Mendelian disorders have not yet been mapped there has been a trend away from studying single-gene disorders. In part, this is due to the fact that many of the remaining single-gene families are not large enough to map the disease locus to a single site in the genome. New tools and approaches are needed to allow researchers to effectively tap into this genetic gold-mine. Towards this goal, we have used haploid cell lines to experimentally validate the use of high-density single nucleotide polymorphism (SNP) arrays to define genome-wide haplotypes and candidate regions, using a small amyotrophic lateral sclerosis (ALS) family as a prototype. Specifically, we used haploid-cell lines to determine if high-density SNP arrays accurately predict haplotypes across entire chromosomes and show that haplotype information significantly enhances the genetic information in small families. Panels of haploid-cell lines were generated and a 5 centimorgan (cM) short tandem repeat polymorphism (STRP) genome scan was performed. Experimentally derived haplotypes for entire chromosomes were used to directly identify regions of the genome identical-by-descent in 5 affected individuals. Comparisons between experimentally determined and in silico haplotypes predicted from SNP arrays demonstrate that SNP analysis of diploid DNA accurately predicted chromosomal haplotypes. These methods precisely identified 12 candidate intervals, which are shared by all 5 affected individuals. Our study illustrates how genetic information can be maximized using readily available tools as a first step in mapping single-gene disorders in small families.
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SNP HiTLink: a high-throughput linkage analysis system employing dense SNP data.
BMC Bioinformatics
PUBLISHED: 04-24-2009
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During this recent decade, microarray-based single nucleotide polymorphism (SNP) data are becoming more widely used as markers for linkage analysis in the identification of loci for disease-associated genes. Although microarray-based SNP analyses have markedly reduced genotyping time and cost compared with microsatellite-based analyses, applying these enormous data to linkage analysis programs is a time-consuming step, thus, necessitating a high-throughput platform.
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Mitochondrial ND3 as the novel causative gene for Leber hereditary optic neuropathy and dystonia.
Neurogenetics
PUBLISHED: 04-17-2009
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Leber hereditary optic neuropathy and dystonia (LDYT) is a mitochondrial disorder associated with variable combinations of vision loss and progressive generalized dystonia. LDYT is a unique oxidative phosphorylation disorder caused by mutations in mitochondrial ND6 or ND4 gene. In this paper, we describe a Chinese family with 18 LDYT patients. The comprehensive nucleotide sequence analysis of the entire mitochondrial genome using resequencing microarray revealed a mutation (mtND3*10197A (m.10197G>A)) substituting a threonine for a highly conserved alanine at codon 47 of MTND3 on the background of haplogroup D4b. Quantitative analysis of the heteroplasmy of the mutation revealed a homoplasmy in the leukocytes of all the affected individuals on the maternal side. This is the first description of the ND3 mutation causing LDYT. The mtND3*10197A (m.10197G>A) mutation has recently been described in French and Korean patients with Leigh syndrome. These findings suggest that the clinical presentations associated with the mtND3*10197A (m.10197G>A) mutation (ND3) are much wider, encompassing those of LDYT and Leigh syndrome.
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Efferent and afferent evoked potentials in patients with adrenomyeloneuropathy.
Clin Neurol Neurosurg
PUBLISHED: 04-08-2009
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This paper investigates efferent and afferent conductions of the central nervous system by various evoked potentials in patients with adrenomyeloneuropathy (AMN).
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[Alien hand sign observed at the initial stage of a case of Creutzfeldt-Jakob disease].
Rinsho Shinkeigaku
PUBLISHED: 04-08-2009
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A 68-year-old man was admitted to our hospital in the mid-October of 2006 because of a one-month history of peculiar movements of the left hand, which had been preceded by one month by awkward motions in the left leg. Upon neurological examination, spontaneous involuntary movement of the left hand was found. His left hand with his index finger stretched moved toward his right side spontaneously. He could not control his left leg freely. Although he showed mild ataxia in his left hand, there was no weakness, no dystonia, and no apraxia. No sensory abnormality was detected except for mild deep-sensation impairment in his left foot. The results of magnetic resonance imaging (MRI) including diffusion-weighted imaging (DWI) were normal; however, single-photon emission computed tomography (SPECT) showed hypoperfusion in the right hemisphere. At the time of admission, although a clinical diagnosis could not be made, we considered that the involuntary movements of his left hand were consistent with alien hand sign (AHS). Two and a half months after its onset, with the development of rapidly progressive dementia and generalized myoclonus, AHS gradually disappeared. Three months after the AHS onset, MRI with DWI showed restricted diffusion within the cortex involving the cingulated gyrus and bilateral temporal lobes, which was more prominent on the right than on the left side. Four months after the AHS onset, 14-3-3 protein level of the cerebrospinal fluid was elevated, and EEG recordings showed diffuse slowing of basic activity with periodic complexes. The patient was clinically diagnosed as having CJD. The patient died of pneumonia four and a half months after the AHS onset. AHS has rarely been reported in patients with CJD. Our case illustrates the importance of considering CJD in the differential diagnosis, if the patient showed AHS, even with normal MRI findings.
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Metastatic CNS lymphoma presenting with periventricular dissemination - MRI and neuropathological findings in an autopsy case.
J. Neurol. Sci.
PUBLISHED: 04-03-2009
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Metastatic CNS lymphoma usually manifests as pachymeningeal or leptomeningeal infiltrates, and periventricular dissemination is rare. A 70-year old man first noticed a mass in the left supraclavicular fossa, and then presented with bilateral parkinsonism, followed by consciousness disturbance. Fluid attenuated inversion recovery (FLAIR) image of brain MRI demonstrated hyperintensities at the parenchyma around the lateral ventricle, third ventricle, and fourth ventricle. Gadolinium-enhanced T1-weighted image demonstrated enhancement along the whole wall of the ventricle. Biopsy of the left supraclavicular lymph nodes established a diagnosis of diffuse large B-cell lymphoma. The patient died of multiple organ failure about 5 months after the onset. Autopsy disclosed periventricular dissemination of lymphoma cells that was most severe around the lateral ventricle. We considered that the lymphoma cells entered the ventricular system through the choroid plexus of the lateral ventricle, followed by dissemination of the periventricular parenchyma.
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A novel ferritin light chain gene mutation in a Japanese family with neuroferritinopathy: description of clinical features and implications for genotype-phenotype correlations.
Mov. Disord.
PUBLISHED: 01-02-2009
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Neuroferritinopathy is a hereditary neurodegenerative disorder caused by mutations in the ferritin light chain gene (FTL1). The cardinal features are progressive movement disturbance, hypoferritinemia, and iron deposition in the brain. To date, five mutations have been described in Caucasian and Japanese families, but the genotype-phenotype correlations remain to be established. We identified a novel FTL1 mutation (exon 4, c.641/642, 4-nucletotide duplication) in a Japanese family and compared the clinical traits with those previously reported. All mutations but one are insertions in exon 4, resulting in frameshifts. Clinical features are similar among patients with the same mutations. Middle-age onset chorea is common in patients with insertions in the 5 portion of exon 4 including our cases, whereas patients with insertions in the 3 portion of exon 4 develop early-onset tremor, suggesting genotype-phenotype correlations. In this family, male predominance and normal serum ferritin levels are characteristic.
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A novel monoclonal antibody reveals a conformational alteration shared by amyotrophic lateral sclerosis-linked SOD1 mutants.
Ann. Neurol.
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Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease that is characterized by the selective loss of upper and lower motoneurons. Although >100 different Cu, Zn superoxide dismutase (SOD1) mutations have been identified in ALS patients, it remains controversial whether all of them are disease-causative mutations. Therefore, it is necessary to develop molecular mechanism-based diagnosis and treatment of ALS caused by SOD1 mutations.
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[A new attempt to promote home medical care in Kashiwa city-usefulness of information and communication technology with seamless multidisciplinary cooperation].
Gan To Kagaku Ryoho
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Due to the rapidly increasing super-aging society, medical policy in Japan should be redefined. Therefore, the medical and nursing home care system should now be revised greatly. We need to change the current principle that is based on cure only. The patients should receive hospitable care closely connected with their life in their home-town(region)throughout their lifetime. This is termed as "home medical care system". Here, we promote patient-centered medical home care, which implements the chronic and/or End-Of-Life care models, in Kashiwa city, Chiba prefecture. This system is a promising framework for primary care transformation. There is a need for a multidisciplinary team-based care system using information and communication technology(ICT)with smooth and seamless cooperation. However, increased awareness among the workers engaged in home medical care is first required.
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A homozygous mutation of C12orf65 causes spastic paraplegia with optic atrophy and neuropathy (SPG55).
J. Med. Genet.
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Autosomal recessive hereditary spastic paraplegias (AR-HSP) constitute a heterogeneous group of neurodegenerative diseases involving pyramidal tracts dysfunction. The genes responsible for many types of AR-HSPs remain unknown. We attempted to identify the gene responsible for AR-HSP with optic atrophy and neuropathy.
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Impairment of hippocampal long-term potentiation and failure of learning in mice treated with d-threo-1-phenyl-2-decanoylamino-3-morpholino-1-propanol.
Biomed. Res.
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Gangliosides (sialic acid-containing glycosphingolipids) play important roles in many physiological functions, including synaptic plasticity in the hippocampus, which has been suggested as the basal cellular process of learning and memory in the brain. In the present study, long-term potentiation (LTP) and long-term depression (LTD) in CA1 hippocampal neurons and learning behavior were examined in mice treated with (D)-threo-1-phenyl-2-decanoylamino-3-morpholino-1-propanol ((D)-PDMP), an inhibitor of ganglioside biosynthesis. Mice treated with (D)-PDMP, but not those treated with (L)-PDMP, showed impairment of LTP induction in hippocampal CA1 neurons without any significant change in LTD formation and also showed a failure of learning in the 4-pellet taking test. These results indicate that de novo synthesis of gangliosides in the brain is involved in synaptic plasticity of LTP in mouse hippocampal CA1 neurons and plays important roles in learning and memory.
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CSF1R mutations identified in three families with autosomal dominantly inherited leukoencephalopathy.
Am. J. Med. Genet. B Neuropsychiatr. Genet.
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Genetic and phenotypic heterogeneities are considerably high in adult-onset leukoencephalopathy, in which comprehensive mutational analyses of the candidate genes by conventional methods are too laborious. We applied exome sequencing to conduct a comprehensive mutational analysis of genes for autosomal dominant leukoencephalopathies. Genomic DNA samples from four patients of three families with autosomal dominantly inherited adult-onset leukodystrophy were subjected to exome sequencing. On the basis of the results, 21 patients with adult-onset sporadic leukodystrophy and one patient with pathologically proven HDLS were additionally screened for CSF1R mutations. Exome sequencing identified heterozygous CSF1R mutations (p.I794T and p.R777W) in two families. I794T has recently been reported as a causative mutation for hereditary diffuse leukoencephalopathy with spheroids (HDLS), and R777W is a novel mutation. Although mutational analysis of CSF1R in 21 sporadic cases revealed no mutations, another novel CSF1R mutation, p.C653Y, was identified in one patient with autopsy-proven HDSL. These variants were located in the PTK domain where the causative mutations cluster. Functional prediction of the mutant CSF1R as well as cross-species conservation of the affected amino acids supports the notion that these variants are pathogenic for HDLS. Exome sequencing is useful for a comprehensive mutational analysis of causative genes for hereditary leukoencephalopathies, and CSF1R should be considered a candidate gene for patients with autosomal dominant leukoencephalopathies.
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Evaluation of the spinal cord white matter.
Okajimas Folia Anat Jpn
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Morphological findings or evaluations of the nervous system have traditionally concentrated on cell somata; evaluations of the white matter have not been put forward up to now. This study was conducted to evaluate the white matter in the spinal cord with the LPH discriminative staining method which was proposed by Goto. Thanks to the minimum shrinkage ratio (10 ± 0% in length) which this technique allows, it is possible to evaluate the sizes of nerve axons, and to compare the arrangement of nerve fibers in various parts of the spinal white matter. As the axonal sizes reflect nerve conduction velocities, we would like to emphasize that these sizes or the differences in the arrangement of axons may be important for a better understanding of neurosymptomatology.
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Nuclei of the human raphe.
Okajimas Folia Anat Jpn
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Along the raphe of the brain stem, a series of small neuronal groups can be observed in the medulla oblongata, the pons and the mesencephalon. The neurons located in and adjacent to the raphe are considered to produce mainly serotonin (5-HT). The groups of nuclei containing 5-HT were first reported in experimental animals in the early 1960s. The presence of such nuclei, however, has not yet been brought to light in the human brainstem except the few atlases, although in several neuroanatomy textbooks, extrapolated data are shown in the form of drawings as if they were the data from the human brain. The aim of this study is to present microscopic photos of such raphe nuclei made from serial sections of the human brainstem, and to clarify the differences between findings in human and textbook drawings from animal data.
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The TRK-fused gene is mutated in hereditary motor and sensory neuropathy with proximal dominant involvement.
Am. J. Hum. Genet.
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Hereditary motor and sensory neuropathy with proximal dominant involvement (HMSN-P) is an autosomal-dominant neurodegenerative disorder characterized by widespread fasciculations, proximal-predominant muscle weakness, and atrophy followed by distal sensory involvement. To date, large families affected by HMSN-P have been reported from two different regions in Japan. Linkage and haplotype analyses of two previously reported families and two new families with the use of high-density SNP arrays further defined the minimum candidate region of 3.3 Mb in chromosomal region 3q12. Exome sequencing showed an identical c.854C>T (p.Pro285Leu) mutation in the TRK-fused gene (TFG) in the four families. Detailed haplotype analysis suggested two independent origins of the mutation. Pathological studies of an autopsied patient revealed TFG- and ubiquitin-immunopositive cytoplasmic inclusions in the spinal and cortical motor neurons. Fragmentation of the Golgi apparatus, a frequent finding in amyotrophic lateral sclerosis, was also observed in the motor neurons with inclusion bodies. Moreover, TAR DNA-binding protein 43 kDa (TDP-43)-positive cytoplasmic inclusions were also demonstrated. In cultured cells expressing mutant TFG, cytoplasmic aggregation of TDP-43 was demonstrated. These findings indicate that formation of TFG-containing cytoplasmic inclusions and concomitant mislocalization of TDP-43 underlie motor neuron degeneration in HMSN-P. Pathological overlap of proteinopathies involving TFG and TDP-43 highlights a new pathway leading to motor neuron degeneration.
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Mutational analysis of familial and sporadic amyotrophic lateral sclerosis with OPTN mutations in Japanese population.
Amyotroph Lateral Scler
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Our objective was to elucidate the genetic epidemiology of familial amyotrophic lateral sclerosis (FALS) and sporadic ALS (SALS) with OPTN mutations in the Japanese population. Mutational analysis of OPTN was conducted in 18 FALS pedigrees in whom mutations in other causative genes have been excluded and in 218 SALS patients by direct nucleotide sequence analysis. Novel non-synonymous variants identified in ALS patients were further screened in 271 controls. Results showed that although no mutations were identified in the FALS pedigrees, a novel heterozygous non-synonymous variant c.481G > A (p.V161M) was identified in one SALS patient, who originated from the southernmost part of the Kii Peninsula. The mutation was not present in 271 controls. As the clinical feature, the patient carrying V161M showed predominantly upper motor neuron signs with slow progression. This study suggests that mutations in OPTN are not the main cause of ALS in the Japanese population.
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C9ORF72 repeat expansion in amyotrophic lateral sclerosis in the Kii peninsula of Japan.
Arch. Neurol.
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In the Kii peninsula of Japan, high prevalences of amyotrophic lateral sclerosis (ALS) and parkinsonism-dementia complex have been reported. There are 2 major foci with a high prevalence, which include the southernmost region neighboring the Koza River (Kozagawa and Kushimoto towns in Wakayama prefecture) and the Hohara district (Mie prefecture).
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Clinical features and haplotype analysis of newly identified Japanese patients with gelsolin-related familial amyloidosis of Finnish type.
Neurogenetics
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Familial amyloidosis of the Finnish type (FAF) is an autosomal dominant form of systematic amyloidosis characterized by lattice corneal dystrophy, cranial neuropathy, and cutis laxa. Although FAF has been frequently found in the Finnish population, FAF is a considerably rare disorder in other regions. In this study, we examined the clinical characteristics as well as the haplotypes of six Japanese patients with FAF from five families. They showed the typical clinical presentations of FAF, but we found a broad range of ages at onset of neurological symptoms. All members had the c.654G>A mutation in GSN. To evaluate the disease haplotypes, high-density single-nucleotide polymorphism (SNP) arrays were used and disease-relevant haplotypes were reconstructed. Haplotype analysis in the four apparently unrelated families suggested a common founder haplotype. In a sporadic FAF patient, however, the haplotype was dissimilar to the founder haplotype. The present study demonstrated that a founder mutation in most of the Japanese families with FAF, except for a sporadic patient in whom a de novo mutation event was suggested as the origin of the mutation.
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Suppressive effect of preconditioning low-frequency stimulation on subsequent induction of long-term potentiation by high frequency stimulation in hippocampal CA3 neurons.
Brain Res.
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We investigated the role of inositol 1, 4, 5-trisphosphate receptors (IP3Rs), activated during preconditioning low-frequency afferent stimulation (LFS), in the subsequent induction of long-term potentiation (LTP) in CA3 neurons in hippocampal slices from mature guinea pigs. Induction of LTP in the field excitatory postsynaptic potential (EPSP) by the delivery of high-frequency stimulation (HFS, a tetanus of two trains of 100 pulses at 100Hz with a 10s interval) to mossy fiber-CA3 neuron synapses was suppressed when CA3 synapses were preconditioned by the LFS of 1000 pulses at 2Hz and this effect was inhibited when the LFS preconditioning was performed in the presence of an IP3R antagonist or a protein phosphatase inhibitor. Furthermore, activation of group 1 metabotropic glutamate receptors (mGluRs) during HFS canceled the effects of an IP3R antagonist given during preconditioning LFS on the subsequent LTP induction at mossy fiber-CA3 synapses. These results suggest that, in hippocampal mossy fiber-CA3 neuron synapses, activation of IP3Rs during a preconditioning LFS results in dephosphorylation events that lead to failure of the HFS to induce subsequent LTP.
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DRPLA transgenic mouse substrains carrying single copy of full-length mutant human DRPLA gene with variable sizes of expanded CAG repeats exhibit CAG repeat length- and age-dependent changes in behavioral abnormalities and gene expression profiles.
Neurobiol. Dis.
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Dentatorubral-pallidoluysian atrophy (DRPLA) is an autosomal dominant progressive neurodegenerative disorder with intellectual deterioration and various motor deficits including ataxia, choreoathetosis, and myoclonus, caused by an abnormal expansion of CAG repeats in the DRPLA gene. Longer expanded CAG repeats contribute to an earlier age of onset, faster progression, and more severe neurological symptoms in DRPLA patients. In this study, we have established DRPLA transgenic mouse lines (sublines) harboring a single copy of the full-length mutant human DRPLA gene carrying various lengths of expanded CAG repeats (Q76, Q96, Q113, and Q129), which have clearly shown motor deficits and memory disturbance whose severity increases with the length of expanded CAG repeats and age, and successfully replicated the CAG repeat length- and age-dependent features of DRPLA patients. Neuronal intranuclear accumulation of the mutant DRPLA protein has been suggested to cause transcriptional dysregulation, leading to alteration in gene expression and neuronal dysfunction. In this study, we have conducted a comprehensive analysis of gene expression profiles in the cerebrum and cerebellum of transgenic mouse lines at 4, 8, and 12 weeks using multiple microarray platforms, and demonstrated that both the number and expression levels of the altered genes are highly dependent on CAG repeat length and age in both brain regions. Specific groups of genes and their function categories were identified by further agglomerative cluster analysis and gene functional annotation analysis. Calcium signaling and neuropeptide signaling, among others, were implicated in the pathophysiology of DRPLA. Our study provides unprecedented CAG-repeat-length-dependent mouse models of DRPLA, which are highly valuable not only for elucidating the CAG-repeat-length-dependent pathophysiology of DRPLA but also for developing therapeutic strategies for DRPLA.
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Increased gene dosage of myelin protein zero causes Charcot-Marie-Tooth disease.
Ann. Neurol.
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On the basis of the hypothesis that copy number mutations of the genes encoding myelin compact proteins are responsible for myelin disorders in humans, we have explored the possibility of copy number mutations in patients with Charcot-Marie-Tooth disease (CMT) whose responsible genes remain undefined.
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JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

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In developing our video relationships, we compare around 5 million PubMed articles to our library of over 4,500 methods videos. In some cases the language used in the PubMed abstracts makes matching that content to a JoVE video difficult. In other cases, there happens not to be any content in our video library that is relevant to the topic of a given abstract. In these cases, our algorithms are trying their best to display videos with relevant content, which can sometimes result in matched videos with only a slight relation.