Faculty Profiles - Ishiura Hiroyuki

Papers - Ishiura Hiroyuki

Division display 101 - 120 of about 229 ／ All the affair displays >>

Expression profile analysis in cells overexpressing <scp>DRPLA cDNA</scp> to explore the roles of <scp>DRPLAp</scp> as a transcriptional coregulator Reviewed

Keiko Hatano, Hidetoshi Date, Hiroyuki Ishiura, Takashi Matsukawa, Masaki Tanaka, Jun Mitsui, Jun Goto, Jun Yoshimura, Koichiro Doi, Shinichi Morishita, Shoji Tsuji

Neurology and Clinical Neuroscience 10 ( 4 ) 210 - 217 2022.7

Comprehensive Genetic Analyses of Inherited Peripheral Neuropathies in Japan: Making Early Diagnosis Possible. Reviewed International journal

Masahiro Ando, Yujiro Higuchi, Junhui Yuan, Akiko Yoshimura, Takaki Taniguchi, Fumikazu Kojima, Yutaka Noguchi, Takahiro Hobara, Mika Takeuchi, Jun Takei, Yu Hiramatsu, Yusuke Sakiyama, Akihiro Hashiguchi, Yuji Okamoto, Jun Mitsui, Hiroyuki Ishiura, Shoji Tsuji, Hiroshi Takashima

Biomedicines 10 ( 7 ) 2022.6

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

Various genomic variants were linked to inherited peripheral neuropathies (IPNs), including large duplication/deletion and repeat expansion, making genetic diagnosis challenging. This large case series aimed to identify the genetic characteristics of Japanese patients with IPNs. We collected data on 2695 IPN cases throughout Japan, in which PMP22 copy number variation (CNV) was pre-excluded. Genetic analyses were performed using DNA microarrays, next-generation sequencing-based gene panel sequencing, whole-exome sequencing, CNV analysis, and RFC1 repeat expansion analysis. The overall diagnostic rate and the genetic spectrum of patients were summarized. We identified 909 cases with suspected IPNs, pathogenic or likely pathogenic variants. The most common causative genes were MFN2, GJB1, MPZ, and MME. MFN2 was the most common cause for early-onset patients, whereas GJB1 and MPZ were the leading causes of middle-onset and late-onset patients, respectively. Meanwhile, GJB1 and MFN2 were leading causes for demyelinating and axonal subtypes, respectively. Additionally, we identified CNVs in MPZ and GJB1 genes and RFC1 repeat expansions. Comprehensive genetic analyses explicitly demonstrated the genetic basis of our IPN case series. A further understanding of the clinical characteristics of IPN and genetic spectrum would assist in developing efficient genetic testing strategies and facilitate early diagnosis.

DOI： 10.3390/biomedicines10071546

PubMed

researchmap

Nonsyndromic arteriopathy and aortopathy and vascular Ehlers–Danlos syndrome <scp> causing COL3A1 </scp> variants Reviewed

Hiroki Yagi, Norifumi Takeda, Eisuke Amiya, Nana Akiyama, Hyangri Chang, Hiroyuki Ishiura, Jiro Sato, Hiroshi Akazawa, Hiroyuki Morita, Issei Komuro

American Journal of Medical Genetics Part A 2022.5

<scp>TDP</scp> ‐43 Proteinopathy Presenting with Typical Symptoms of Parkinson's Disease Reviewed

Rika Yamashita, Goichi Beck, Yuki Yonenobu, Kimiko Inoue, Akihiko Mitsutake, Hiroyuki Ishiura, Masato Hasegawa, Shigeo Murayama, Hideki Mochizuki

Movement Disorders 2022.5

Novel de novo POLR3B mutations responsible for demyelinating Charcot-Marie-Tooth disease in Japan. Reviewed International journal

Masahiro Ando, Yujiro Higuchi, Jun-Hui Yuan, Akiko Yoshimura, Ruriko Kitao, Takehiko Morimoto, Takaki Taniguchi, Mika Takeuchi, Jun Takei, Yu Hiramatsu, Yusuke Sakiyama, Akihiro Hashiguchi, Yuji Okamoto, Jun Mitsui, Hiroyuki Ishiura, Shoji Tsuji, Hiroshi Takashima

Annals of clinical and translational neurology 9 ( 5 ) 747 - 755 2022.5

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

BACKGROUND: Biallelic POLR3B mutations cause a rare hypomyelinating leukodystrophy. De novo POLR3B heterozygous mutations were recently associated with afferent ataxia, spasticity, variable intellectual disability, and epilepsy, and predominantly demyelinating sensorimotor peripheral neuropathy. METHODS: We performed whole-exome sequencing (WES) of DNA samples from 804 Charcot-Marie-Tooth (CMT) cases that could not be genetically diagnosed by DNA-targeted resequencing microarray using next-generation sequencers. Using WES data, we analyzed the POLR3B mutations and confirmed their clinical features. RESULTS: We identified de novo POLR3B heterozygous missense mutations in two patients. These patients presented with early-onset demyelinating sensorimotor neuropathy without ataxia, spasticity, or cognitive impairment. Patient 1 showed mild cerebellar atrophy and spinal cord atrophy on magnetic resonance imaging and eventually died of respiratory failure in her 50s. We classified these mutations as pathogenic based on segregation studies, comparison with control database, and in silico analysis. CONCLUSION: Our study is the third report on patients with demyelinating CMT harboring heterozygous POLR3B mutations and verifies the pathogenicity of POLR3B mutations in CMT. Although extremely rare in our large Japanese case series, POLR3B mutations should be added to the CMT-related gene panel for comprehensive genetic screening, particularly for patients with early-onset demyelinating CMT.

DOI： 10.1002/acn3.51555

PubMed

researchmap

Efficacy of canakinumab on AA amyloidosis in late-onset NLRP3-associated autoinflammatory disease with an I574F somatic mosaic mutation. Reviewed International journal

Takahiro Itamiya, Toshihiko Komai, Hiroko Kanda, Yasuo Nagafuchi, Hyangri Chang, Shota Shibata, Hiroyuki Ishiura, Hirofumi Shoda, Tatsushi Toda, Keishi Fujio

Clinical rheumatology 2022.3

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

There have been hundreds of reports on mutations in the NLRP3 gene related to NLRP3-associated autoinflammatory disease, but few of these mutations have occurred as both germline and somatic mosaic mutations. In this case-based review, we report a 68-year-old man with an NLRP3-associated autoinflammatory disease. He developed secondary amyloidosis, including a renal and colorectal presentation in his 50 s. Sequencing of the NLRP3 gene revealed an I574F somatic mosaic mutation, which has up to now only been reported in germline mutations. The patient was treated with canakinumab, which had great efficacy not only on the NLRP3-mediated inflammation, but also on the chronic renal failure and proteinuria provoked by secondary renal amyloidosis. To evaluate the effectiveness of canakinumab, we conducted a literature research on renal amyloidosis related to NLRP3-associated autoinflammatory disease treated with canakinumab. Although our patient had a relatively long medical history and greater amounts of proteinuria than other reported cases, canakinumab had great efficacy on renal impairment, in similar to other reported cases. Along with the first report of a late-onset I574F somatic mosaic mutation in NLRP3-associated autoinflammatory disease, this report demonstrates the effectiveness of canakinumab on renal amyloidosis, probably through the way that IL-1β blockade minimizes podocyte injury.

DOI： 10.1007/s10067-022-06130-1

PubMed

researchmap

Complex hereditary peripheral neuropathies caused by novel variants in mitochondrial-related nuclear genes. Reviewed International journal

Yu Hiramatsu, Yuji Okamoto, Akiko Yoshimura, Jun-Hui Yuan, Masahiro Ando, Yujiro Higuchi, Akihiro Hashiguchi, Eiji Matsuura, Fumihito Nozaki, Tomohiro Kumada, Kei Murayama, Mikiya Suzuki, Yuki Yamamoto, Naoko Matsui, Yoshimichi Miyazaki, Masamitsu Yamaguchi, Youji Suzuki, Jun Mitsui, Hiroyuki Ishiura, Masaki Tanaka, Shinichi Morishita, Ichizo Nishino, Shoji Tsuji, Hiroshi Takashima

Journal of neurology 269 ( 8 ) 4129 - 4140 2022.3

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

Mitochondrial disorders are a group of clinically and genetically heterogeneous multisystem disorders and peripheral neuropathy is frequently described in the context of mutations in mitochondrial-related nuclear genes. This study aimed to identify the causative mutations in mitochondrial-related nuclear genes in suspected hereditary peripheral neuropathy patients. We enrolled a large Japanese cohort of clinically suspected hereditary peripheral neuropathy patients who were mutation negative in the prescreening of the known Charcot-Marie-Tooth disease-causing genes. We performed whole-exome sequencing on 247 patients with autosomal recessive or sporadic inheritance for further analysis of 167 mitochondrial-related nuclear genes. We detected novel bi-allelic likely pathogenic/pathogenic variants in four patients, from four mitochondrial-related nuclear genes: pyruvate dehydrogenase beta-polypeptide (PDHB), mitochondrial poly(A) polymerase (MTPAP), hydroxyacyl-CoA dehydrogenase/3-ketoacyl-CoA thiolase/enoyl-CoA hydratase, beta subunit (HADHB), and succinate-CoA ligase ADP-forming beta subunit (SUCLA2). All these patients showed sensory and motor axonal polyneuropathy, combined with central nervous system or multisystem involvements. The pathological analysis of skeletal muscles revealed mild neurogenic changes without significant mitochondrial abnormalities. Targeted screening of mitochondria-related nuclear genes should be considered for patients with complex hereditary axonal polyneuropathy, accompanied by central nervous system dysfunctions, or with unexplainable multisystem disorders.

DOI： 10.1007/s00415-022-11026-w

PubMed

researchmap

Muscle Transcriptomics Shows Overexpression of Cadherin 1 in Inclusion Body Myositis. Reviewed International journal

Chiseko Ikenaga, Hidetoshi Date, Motoi Kanagawa, Jun Mitsui, Hiroyuki Ishiura, Jun Yoshimura, Iago Pinal-Fernandez, Andrew L Mammen, Thomas E Lloyd, Shoji Tsuji, Jun Shimizu, Tatsushi Toda, Jun Goto

Annals of neurology 91 ( 3 ) 317 - 328 2022.3

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

OBJECTIVE: This study aimed to elucidate the molecular features of inclusion body myositis (IBM). METHODS: We performed RNA sequencing analysis of muscle biopsy samples from 67 participants, consisting of 58 myositis patients with the pathological finding of CD8-positive T cells invading non-necrotic muscle fibers expressing major histocompatibility complex class I (43 IBM, 6 polymyositis, and 9 unclassifiable myositis), and 9 controls. RESULTS: Cluster analysis, principal component analysis, and pathway analysis showed that differentially expressed genes and pathways identified in IBM and polymyositis were mostly comparable. However, pathways related to cell adhesion molecules were upregulated in IBM as compared with polymyositis and controls (p < 0.01). Notably, CDH1, which encodes the epidermal cell junction protein cadherin 1, was overexpressed in the muscles of IBM, which was validated by another RNA sequencing dataset from previous publications. Western blotting confirmed the presence of mature cadherin 1 protein in the muscles of IBM. Immunohistochemical staining confirmed the positivity for anti-cadherin 1 antibody in the muscles of IBM, whereas there was no muscle fiber positive for anti-cadherin 1 antibody in immune-mediated necrotizing myopathy, antisynthetase syndrome, and controls. The fibers stained with anti-cadherin 1 antibody did not have rimmed vacuoles or abnormal protein accumulation. Experimental skeletal muscle regeneration and differentiation systems showed that CDH1 is expressed during skeletal muscle regeneration and differentiation. INTERPRETATION: CDH1 was detected as a differentially expressed gene, and immunohistochemistry showed that cadherin 1 exists in the muscles of IBM, whereas it was rarely seen in those of other idiopathic inflammatory myopathies. Cadherin 1 upregulation in muscle could provide a valuable clue to the pathological mechanisms of IBM. ANN NEUROL 2022;91:317-328.

DOI： 10.1002/ana.26304

PubMed

researchmap

Family with congenital contractural arachnodactyly due to a novel multiexon deletion of the FBN2 gene. Reviewed International journal

Hiroki Yagi, Hiroshi Takiguchi, Norifumi Takeda, Ryo Inuzuka, Yuki Taniguchi, Kristine Joyce Porto, Hiroyuki Ishiura, Jun Mitsui, Hiroyuki Morita, Issei Komuro

Clinical case reports 10 ( 2 ) e05335 2022.2

An immigrant family with Kii amyotrophic lateral sclerosis/parkinsonism-dementia complex. Reviewed International journal

Yasumasa Kokubo, Satoru Morimoto, Ryogen Sasaki, Masato Hasegawa, Hiroyuki Ishiura, Shoji Tsuji, Mari Yoshida, Naohisa Yamazoe, Mitsukazu Miyazaki, Shigeki Kuzuhara

Neurological sciences : official journal of the Italian Neurological Society and of the Italian Society of Clinical Neurophysiology 43 ( 2 ) 1423 - 1425 2022.2

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

OBJECTIVES: Amyotrophic lateral sclerosis/parkinsonism-dementia complex (ALS/PDC) is a unique endemic on Guam island of the USA, the Kii Peninsula of Japan, and Papua state of Indonesia. The pathomechanism of ALS/PDC remains to be solved, although interaction between some environmental factors and genetic background is plausible. This is the first autopsy-proven immigrant family of ALS/PDC of the Kii Peninsula. METHODS: A daughter and her father immigrated to the high incident area from outside the Kii Peninsula. The father developed ALS 18 years later after immigration, and his daughter also developed ALS 65 years after immigration. They showed pure ALS phenotype without parkinsonism and dementia. RESULTS: The daughter was diagnosed neuropathologically with Kii ALS/PDC with multiple proteinopathies: tauopathy, α-synucleinopathy, and TDP-43 proteinopathy. Gene analysis of familial ALS-related genes, including C9orf72, showed no mutation. DISCUSSION: The findings in an immigrant family established that certain environmental factors play a critical role in the pathogenesis of Kii ALS/PDC.

DOI： 10.1007/s10072-021-05737-7

PubMed

researchmap

An NEFH founder mutation causes broad phenotypic spectrum in multiple Japanese families. Reviewed International journal

Masahiro Ando, Yujiro Higuchi, Yuji Okamoto, Junhui Yuan, Akiko Yoshimura, Jun Takei, Takaki Taniguchi, Yu Hiramatsu, Yusuke Sakiyama, Akihiro Hashiguchi, Eiji Matsuura, Hiroto Nakagawa, Ken Sonoda, Toru Yamashita, Akiko Tamura, Hideo Terasawa, Jun Mitsui, Hiroyuki Ishiura, Shoji Tsuji, Hiroshi Takashima

Journal of human genetics 67 ( 7 ) 399 - 403 2022.1

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

BACKGROUND AND AIMS: Mutations in neurofilament genes have been linked to several neuromuscular disorders. The neurofilament heavy (NEFH) gene was identified as the causative gene of Charcot-Marie-Tooth disease type 2CC (CMT2CC) in 2016, with a toxic gain of function mechanism caused by the translation and aggregation of cryptic amyloidogenic element (CAE) in the 3' untranslated region (UTR). But the NEFH-related clinical and genetic spectrums are still unclear in Japan. METHODS: We analyzed all variants in the NEFH gene from our in-house whole-exome sequencing data, established from Japanese nationwide patients with neuromuscular disorders, including Charcot-Marie-Tooth (CMT) disease and spinal muscular atrophy (SMA). RESULTS: We identified a c.3017dup (p.Pro1007Alafs*56) variant in NEFH from three families clinically diagnosed with CMT, and one family with SMA. In addition to the patients presented with typical peripheral neuropathies, pyramidal signs were observed from one CMT patient. Whereas the SMA patients showed severe characteristic weakness of triceps brachii and quadriceps femoris. All of these four families reside in Kagoshima Prefecture of Japan, and a following haplotype analysis strongly suggests a founder effect. INTERPRETATION: This is the original report referring to a founder mutation in NEFH. The clinical diversity in our study, comprising CMT, with or without pyramidal signs, and SMA, suggest an extensive involvement of peripheral nerve, anterior horn cells, or both. Our findings broaden the phenotypic spectrum of NEFH-related disorders.

DOI： 10.1038/s10038-022-01019-y

PubMed

researchmap

Elderly patients with suspected Charcot-Marie-Tooth disease should be tested for the TTR gene for effective treatments. Reviewed International journal

Takaki Taniguchi, Masahiro Ando, Yuji Okamoto, Akiko Yoshimura, Yujiro Higuchi, Akihiro Hashiguchi, Nozomu Matsuda, Mamoru Yamamoto, Eisuke Dohi, Makoto Takahashi, Masanao Yoshino, Taichi Nomura, Masaaki Matsushima, Ichiro Yabe, Yui Sanpei, Hiroyuki Ishiura, Jun Mitsui, Masanori Nakagawa, Shoji Tsuji, Hiroshi Takashima

Journal of human genetics 67 ( 6 ) 353 - 362 2022.1

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

BACKGROUND AND AIMS: Some hereditary transthyretin (ATTRv) amyloidosis patients are misdiagnosed as Charcot-Marie-Tooth disease (CMT) at onset. We assess the findings to identify ATTRv amyloidosis among patients with suspected CMT to screen transthyretin gene variants for treatments. METHODS: We assessed clinical, cerebrospinal fluid, and electrophysiological findings by comparing ATTRv amyloidosis patients with suspected CMT (n = 10) and CMT patients (n = 489). RESULTS: The median (interquartile range) age at onset of neurological symptoms was 69 (64.2-70) years in the ATTRv amyloidosis vs 12 (5-37.2) years in CMT group (Mann-Whitney U, p < 0.01). The proportion of patients with initial sensory symptoms was 70% in the ATTRv amyloidosis group vs 7.1% in CMT group (Fisher's exact, p < 0.01). The proportion of patients with histories of suspected chronic inflammatory demyelinating polyneuropathy (CIDP) were 50% in the ATTRv amyloidosis group vs 8.7% in CMT group (Fisher's exact, p < .01). Other measures and outcomes were not different between the two groups. Five of the six patients with ATTRv amyloidosis received treatment and survived. INTERPRETATION: For effective treatments, the transthyretin gene should be screened in patients with suspected CMT with old age at onset of neurological symptoms, initial sensory symptoms, and histories of suspected CIDP.

DOI： 10.1038/s10038-021-01005-w

PubMed

researchmap

Multi-type RFC1 repeat expansions as the most common cause of hereditary sensory and autonomic neuropathy. Reviewed International journal

Jun-Hui Yuan, Yujiro Higuchi, Masahiro Ando, Eiji Matsuura, Akihiro Hashiguchi, Akiko Yoshimura, Tomonori Nakamura, Yusuke Sakiyama, Jun Mitsui, Hiroyuki Ishiura, Shoji Tsuji, Hiroshi Takashima

Frontiers in neurology 13 986504 - 986504 2022

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

Non-coding repeat expansions within RFC1 and NOTCH2NLC genes have lately been linked to multisystem neurodegenerative diseases, which also shed light on yet undiagnosed patients with inherited peripheral neuropathies. The aim of this study was to identify the genetic basis of patients with hereditary sensory and autonomic neuropathy (HSAN). We collected 79 unrelated DNA samples clinically suspected with HSAN from multiple regions of Japan. Mutation screening was first performed using gene panel sequencing and whole-exome sequencing. Pathogenic/likely pathogenic variants were identified from genes of WNK1/HSN2 (6 cases), SCN9A (3 cases), NTRK1 (3 cases), and DNMT1 (2 cases). Subsequently, long-range flanking PCR and repeat-primed PCR were applied to analyze repeat expansions in RFC1 and NOTCH2NLC. Bi-allelic RFC1 repeat expansions were detected from 20 adult-onset HSAN patients, consisting of [(AAGGG)exp/(AAGGG)exp] (8 cases), [(ACAGG)exp/(ACAGG)exp] (8 cases), and [(AAGGG)exp/(ACAGG)exp] (4 cases). GGC repeat expansion in NOTCH2NLC was found in 1 case. Single-nucleotide variant-based haplotype analysis of patients harboring disease-associated repeat expansions in RFC1 revealed distinguishable haplotypes among subgroups with different repeat genotypes. These findings substantially redefine the genetic spectrum of HSAN, where multi-type RFC1 repeat expansions account for 25.3% of all patients, highlighting the necessity of genetic screening, particularly for adult-onset patients.

DOI： 10.3389/fneur.2022.986504

PubMed

researchmap

DMD exon 2 duplication due to a complex genomic rearrangement is associated with a somatic mosaicism. Reviewed International journal

Akatsuki Kubota, Hiroyuki Ishiura, Kristine Joyce Linay Porto, Masaki Tanaka, Jun Mitsui, Atsushi Unuma, Hisataka Maki, Issei Komuro, Shoji Tsuji, Jun Shimizu, Tatsushi Toda

Neuromuscular disorders : NMD 32 ( 3 ) 263 - 269 2021.12

Language：English

We report the case of a patient with dystrophinopathy caused by DMD exon 2 duplication, showing marked asymmetric muscle atrophy. Immunostaining of the biopsied muscle tissue showed a mosaic staining, suggesting a somatic mosaicism. Polymerase chain reaction (PCR) analysis showed only one breakpoint, and long-read whole-genome sequencing revealed the entire structure of the rearranged sequence. The complex rearrangement was composed of two tandem duplications: one showed a microhomology near the breakpoint, suggesting a microhomology-mediated mechanism, whereas the other was associated with flanking short tandem repeats. The long-read sequencing also suggested the presence of a wild-type nonduplicated sequence, supporting somatic mosaicism. Whereas complementary DNA and western blot analyses were not useful, droplet digital PCR (ddPCR) analysis showed an average copy number of 1.61, enabling accurate estimation of the proportion of cells containing the duplication. Long-read sequencing and ddPCR analysis were useful for revealing the rearrangements and the precise copy number.

DOI： 10.1016/j.nmd.2021.12.004

PubMed

researchmap

Randomized, double-blind, placebo-controlled phase 1 study to evaluate the safety and pharmacokinetics of high doses of ubiquinol in healthy adults Reviewed

Jun Mitsui, Takashi Matsukawa, Masaki Tanaka, Naoko Saito-Sato, Fumiko Kusunoki Nakamoto, Tsutomu Yasuda, Hiroya Naruse, Miho Kawabe Matsukawa, Hiroyuki Ishiura, Midori Nagase, Yorihiro Yamamoto, Haruko Kuzuyama, Ikue Wada, Toshio Ga, Tsutomu Yamazaki, Takashi Moritoyo, Shoji Tsuji

NEUROLOGY AND CLINICAL NEUROSCIENCE 2021.12

Frequency of FMR1 Premutation Alleles in Patients with Undiagnosed Cerebellar Ataxia and Multiple System Atrophy in the Japanese Population. Reviewed International journal

Asem Almansour, Hiroyuki Ishiura, Jun Mitsui, Takashi Matsukawa, Miho Kawabe Matsukawa, Hideaki Shimizu, Atsuhiko Sugiyama, Tatsushi Toda, Shoji Tsuji

Cerebellum (London, England) 2021.11

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

Fragile X-associated tremor/ataxia syndrome (FXTAS) is an adult-onset neurodegenerative disorder caused by FMR1 premutation expansion of CGG repeats. FXTAS can be misdiagnosed with many neurodegenerative disorders manifesting with cerebellar ataxias owing to their overlapping clinical and radiological features. The frequency of the FMR1 premutation allele in Japan has not been fully determined. Herein, we aimed to determine the frequency of FMR1 premutation alleles in Japanese patients with undiagnosed cerebellar ataxia and multiple system atrophy, using repeat-primed PCR in 186 patients with adult onset of undiagnosed cerebellar ataxia and 668 patients with multiple system atrophy, to identify expanded CGG repeats as well as to detect AGG interruptions within the expanded alleles. The size of expansions was estimated using fragment length analysis of PCR products obtained by conventional PCR employing a pair of unique primers flanking the repeat sequence. We identified FMR1 premutation alleles in three male patients. One patient revealed 84 repeat units with one AGG interruption and another patient showed 103 repeat units. Both had presented with sporadic cerebellar ataxia, giving an estimated frequency of 3.7% among Japanese male patients with sporadic cerebellar ataxia with age at onset above 50 years. One patient with the clinical diagnosis of multiple system atrophy harbored 60 repeat units with four AGG interruptions. FMR1 intermediate alleles were observed in two males and one female among the multiple system atrophy patients. We found that genetic tests for FMR1 premutation should be considered in Japanese male patients with cerebellar ataxia with the age at onset above 50 years.

DOI： 10.1007/s12311-021-01329-5

PubMed

researchmap

Diagnostic Values of Venous Peak Lactate, Lactate-to-pyruvate Ratio, and fold Increase in Lactate from Baseline in Aerobic Exercise Tests in Patients with Mitochondrial Diseases.

Masanori Kurihara, Yusuke Sugiyama, Masaki Tanaka, Kenichiro Sato, Akihiko Mitsutake, Hiroyuki Ishiura, Akatsuki Kubota, Kaori Sakuishi, Toshihiro Hayashi, Atsushi Iwata, Jun Shimizu, Kei Murayama, Shoji Tsuji, Tatsushi Toda

Internal medicine (Tokyo, Japan) 61 ( 13 ) 1939 - 1946 2021.11

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

Objective Although aerobic exercise tests on cycle ergometry have long been used for initial assessments of cases of suspected mitochondrial disease, the test parameters in patients with final diagnoses of other diseases via the widely used 15 W for 15 min exercise protocol have not been fully characterized. Methods and Patients We retrospectively reviewed all patients who underwent the test at our institution. We classified the patients with genetic diagnoses or those who met previously reported clinical criteria as having mitochondrial diseases and those with a final diagnosis of another disease as having other diseases. Results were available from 6 patients with mitochondrial disease and 15 with other diseases. Results During the test, elevated venous peak lactate above the upper normal limit of healthy controls at rest (19.2 mg/dL [2.13 mM]) was observed in 3 patients with mitochondrial diseases (50.0%) and 5 with other diseases (33.3%). In the group of patients with elevated venous peak lactate, a lactate-to-pyruvate ratio of >20 was observed in all 3 patients with mitochondrial disease but in only 1 of the 5 with other diseases. More than a 2-fold increase in venous lactate from baseline was observed in 4 patients with mitochondrial disease (66.7%) and 1 with another disease (6.7%). Conclusion Elevated venous peak lactate levels were observed in patients with final diagnoses of other diseases, even under a low 15-min workload at 15 W. The lactate-to-pyruvate ratio and increase in lactate level from baseline may add diagnostic value to venous peak lactate levels alone.

DOI： 10.2169/internalmedicine.8629-21

PubMed

researchmap

COQ2 V393A confers high risk susceptibility for multiple system atrophy in East Asian population. International journal

Kristine Joyce Porto, Makito Hirano, Jun Mitsui, Ayaka Chikada, Takashi Matsukawa, Hiroyuki Ishiura, Tatsushi Toda, Susumu Kusunoki, Shoji Tsuji

Journal of the neurological sciences 429 117623 - 117623 2021.10

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

Multiple system atrophy (MSA) is a rare, late-onset, and devastating neurodegenerative disease characterized by autonomic failure, alongside with various combination of parkinsonism, cerebellar ataxia, and pyramidal dysfunction. Since we first identified biallelic mutations in the COQ2 gene in two multiplex MSA families and further reported that heterozygous COQ2 V393A variant confers a susceptibility to sporadic MSA, the results of nearly a decade of investigating this association globally were quite remarkable. COQ2 V393A was virtually absent in the American and European populations but was shown to have varying associations with sporadic MSA in the East Asian populations. In our attempt to clarify the latter and provide a coherent regional conclusion, we conducted two independent case-control series which showed clear association of the V393A variant with sporadic MSA in the Japanese population. We then pooled the results with other studies from the East Asian population and conducted a meta-analysis which broadened and established the association regionally (pooled OR 2.12, 95% CI: 1.35-3.31, PI: 0.63-7.15, p = 0.0047). The subgroup analysis identified a strong association of V393A with MSA-C (pooled OR 2.57, 95% CI: 1.98-3.35; p = 2.56 × 10-12) but not with MSA-P (pooled OR 1.41, 95% CI: 0.88-2.26; p = 0.16). Our results highlighted the importance of investigating region-specific and pan-regional genetic variants that may potentially underlie the pathomechanisms of neurodegenerative diseases. COQ2 V393A variant remains a susceptibility variant rather than causative for MSA particularly, MSA-C subtype, in the East Asian population.

DOI： 10.1016/j.jns.2021.117623

PubMed

researchmap

Severe dilated cardiomyopathy and ventricular arrhythmia in a patient with Emery‐Dreifuss muscular dystrophy harboring a novel frameshift mutation in EMD

Akihiko Mitsutake, Atsushi Unuma, Mizuho Kawai, Akatsuki Kubota, Hiroyuki Ishiura, Kaori Sakuishi, Jun Shimizu, Hisataka Maki, Eisuke Amiya, Masaru Hatano, Issei Komuro, Shoji Tsuji, Tatsushi Toda

Neurology and Clinical Neuroscience 9 ( 6 ) 490 - 493 2021.10

Clinical Impact of Copy Number Variation on the Genetic Diagnosis of Syndromic Aortopathies. International journal

Norifumi Takeda, Ryo Inuzuka, Hiroki Yagi, Hiroyuki Morita, Masahiko Ando, Haruo Yamauchi, Yuki Taniguchi, Kristine Joyce Porto, Tsubasa Kanaya, Hiroyuki Ishiura, Jun Mitsui, Shoji Tsuji, Tatsushi Toda, Minoru Ono, Issei Komuro

Circulation. Genomic and precision medicine 14 ( 4 ) CIRCGEN121003458 2021.7

　 PREV - NEXT 　

< Ishiura Hiroyuki >

Papers - Ishiura Hiroyuki