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Biomedical subjects

Ichiro Yabe

Publications and source records attributed to Ichiro Yabe.

35 records · Page 2Linked to original sources

Positional vertigo and macroscopic downbeat positioning nystagmus in spinocerebellar ataxia type 6 (SCA6).

To investigate the frequency of positioning nystagmus in degenerative ataxic disorders, we examined downbeat positioning nystagmus (DPN) in 25 patients with spinocerebellar ataxia type 6 (SCA6) and 58 patients with other types of degenerative ataxia. DPN was observed in 21 of the 25 patients with SCA6 (84 %) versus only 3 of the 58 patients (5.2 %) with other types of degenerative ataxia, including multiple system atrophy, SCA1, SCA2, SCA3/Machado-Joseph disease, and non-SCA6 late-onset pure cerebellar ataxia. Our findings indicated that DPN is a distinct part of the clinical presentation of SCA6, showing that vestibular cerebellum is more affected in SCA6 than other types of degenerative ataxia.

Adult↗

C-C chemokine receptor 2 gene polymorphism in Japanese patients with multiple sclerosis.

C-C chemokine receptor 2 (CCR2) is a receptor for chemoattractant protein-1 (MCP-1) and associated with infiltrating lymphocytes in chronic active multiple sclerosis (MS) lesions. To study the role of CCR2 gene in the development of MS, we investigated the CCR2-64I polymorphism in 122 MS patients and 112 healthy controls in a Japanese population. We also analysed the influence of CCR2-64I polymorphism on the clinical course, age at disease onset, and severity. The distribution of the CCR2-64I allele was significantly different between patients and controls (p=0.0187), and the 64I/64I homozygote was significantly less common in MS than in control. Logistic analysis, adjusted for HLA-DRB1*1501-positivity, revealed negative association between the CCR2-64I and MS (p=0.0204). There were no significant associations between CCR2 polymorphism and the clinical features of MS. Our results indicate that the presence of CCR2-64I allele seems to provide protection against the development of MS.

Adolescent↗

Genetic polymorphisms of osteopontin in association with multiple sclerosis in Japanese patients.

Osteopontin (OPN) exhibits pleiotropic functions and abundant transcripts for OPN are present in brains of patients with multiple sclerosis (MS). The aim of this study was to investigate the role of OPN genes in the pathogenesis of MS. Polymorphisms at the 8090th, 9250th and 9583rd positions in OPN were detected by PCR-RFLP from DNAs of 116 MS Japanese patients and 124 healthy controls. The C/C genotype at the 8090th position in exon 6 was more prevalent in MS than in control (p<0.0001), and C allele was more prevalent in MS than in control (p<0.0001, OR=2.57, 95% CI=1.65-4.00). For the 9583rd position polymorphism in exon 7, patients with G/G genotype (age; 32.1+/-12.5 years, mean+/-S.D.) showed a later disease onset than G/A (age; 25.9+/-7.8 years, p=0.01) and A/A (age; 25.2+/-8.9 years, p=0.01) genotypes. There were no significant correlations between OPN gene polymorphisms and disease progression. Our results suggest that the 8090th polymorphism might be associated with susceptibility to MS, while the 9583rd polymorphism might be associated with age of onset of MS.

Adult↗

[Susceptibility genes for multiple sclerosis].

Multiple lines of evidence support the role of genetic factors for susceptibility to multiple sclerosis (MS), although unknown environmental factors must play an important role in developing MS. In this paper, we review the reports studied for the possible associations between Japanese MS and candidate genes by using case-control method. As for HLA alleles, HLA-DRB1*1501 and -DPB1*0501 allele have been confirmed to be associated with conventional MS and opticospinal MS, respectively. Some polymorphisms of vitamin D receptor gene, estrogen receptor gene, CTLA-4 gene, and osteopontin gene were reported to be associated with conventional MS. Appropriate case ascertainment and collection as well as proper statistical method are needed to isolate the susceptibility genes for MS.

Alleles↗

An assessment of the association between IL-2 gene polymorphisms and Japanese patients with multiple sclerosis.

Interleukin-2 (IL-2) is a cytokine intimately involved with both the function and regulation of the immune system. Genetic analysis of experimental autoimmune encephalomyelitis (EAE) provides strong evidence supporting the candidacy of IL-2 as a susceptibility gene. We investigated the association of two single nucleotide polymorphisms (SNPs) at position -384 in the promoter region and +114 in the first exon of the IL-2 gene through a case-control study involving 113 Japanese patients with multiple sclerosis (MS) and 118 healthy controls. Our results showed no significant differences in the distribution of the two polymorphisms between MS patients and controls. Furthermore, no association was observed between IL-2 gene polymorphisms and clinical characteristics, such as clinical course and age at disease onset. Together, our findings suggest that IL-2 gene polymorphisms do not influence the susceptibility to MS or the clinical characteristics of MS in Japanese patients.

Adult↗

An examination of the Apo-1/Fas promoter Mva I polymorphism in Japanese patients with multiple sclerosis.

BACKGROUND: The Apo-1/Fas (CD95) molecule is an apoptosis-signaling cell surface receptor belonging to the tumor necrosis factor (TNF) receptor family. Both Fas and Fas ligand (FasL) are expressed in activated mature T cells, and prolonged cell activation induces susceptibility to Fas-mediated apoptosis. The Apo-1/Fas gene is located in a chromosomal region that shows linkage in multiple sclerosis (MS) genome screens, and studies indicate that there is aberrant expression of the Apo-1/Fas molecule in MS. METHODS: Mva I polymorphism on the Apo-1/Fas promoter gene was detected by PCR-RFLP from the DNA of 114 Japanese patients with conventional MS and 121 healthy controls. We investigated the association of the Mva I polymorphism in Japanese MS patients using a case-control association study design. RESULTS: We found no evidence that the polymorphism contributes to susceptibility to MS. Furthermore, there was no association between Apo-1/Fas gene polymorphisms and clinical course (relapsing-remitting course or secondary-progressive course). No significant association was observed between Apo-1/Fas gene polymorphisms and the age at disease onset. CONCLUSIONS: Overall, our findings suggest that Apo-1/Fas promoter gene polymorphisms are not conclusively related to susceptibility to MS or the clinical characteristics of Japanese patients with MS.

Adult↗

Effect of geranylgeranylaceton on cellular damage induced by proteasome inhibition in cultured spinal neurons.

We investigated the effect of two proteasome inhibitors, lactacystin and epoxomicin, on cultured spinal cord neurons. The incubation of spinal neurons with proteasome inhibitors for 24 hr induced neurotoxicity in a dose-dependent manner. We found motor neurons to be more vulnerable to proteasome-induced neurotoxicity than nonmotor neurons. The staining of cell bodies in treated motor neurons was markedly disrupted and showed characteristic granular patterns. Proteasome-induced neurotoxicity is accompanied by apoptotic nuclear changes, posttranslational modification of the cellular proteins, generation of intracellular free radicals, reduction in the amount of reduced glutathione, and mitochondrial dysfunction. Neurotoxicity was reduced by the administration of low concentrations (1-100 nM) of geranylgeranylacetone (GGA), which is widely used as an antiulcer drug, although higher concentrations of this drug produced neurotoxicity in spinal cord neurons. GGA was found to induce the expression of heat shock protein 70 as well as thioredoxin, which may partly contribute to the protective effect of GGA. These data suggest that the inhibition of proteasome may play a role in the mechanism of neurodegenerative diseases of the spinal cord, such as amyotrophic lateral sclerosis, and that the use of GGA may be effective in the treatment of these conditions.

Acetylcysteine↗

Late onset ataxia phenotype in dentatorubro-pallidoluysian atrophy (DRPLA).

ABSTRACT We clinically and genetically studied three patients in a family with dentatorubro-pallidoluysian atrophy (DRPLA). The proband patient had 58/24 CAG repeat alleles of the DRPLA gene (normal < or = 34 repeats). Cerebellar ataxia first developed in the 6-7th decades and was the predominant feature for more than 10 years in all three, after which two of them manifested dementia and choreiform movements in the advanced stage. Atrophy of the cerebellum and brain stem an CT or MRI had suggested dominant spinocerebellar ataxia as a diagnosis in their ataxia-predominant stage, with a diagnosis of DRPLA being impossible based on the clinical findings alone. Our experience implies that DRPLA must be taken into account in the differential diagnosis of late onset ataxic disorders, since it can easily be overlooked.

Aged↗

No association of vitamin D-binding protein gene polymorphisms in Japanese patients with MS.

Vitamin D-binding protein (DBP) is known to function as an immunomodulatory factor, as well as the main carrier of vitamin D. We analyzed the frequencies of two polymorphisms (codon 416 and codon 420) in the DBP gene through a case-control study involving 107 Japanese patients with multiple sclerosis (MS) and 109 healthy controls. None of these polymorphisms showed any association with the occurrence of MS. Furthermore, no association was observed between the DBP polymorphisms and the age at disease onset. These results suggest that DBP does not contribute to the development of MS in Japanese.

Adjuvants, Immunologic↗

Estrogen receptor gene polymorphism and multiple sclerosis in Japanese patients: interaction with HLA-DRB1*1501 and disease modulation.

We investigated PvuII and XbaI polymorphism in the estrogen receptor gene (ERG) and HLA-DRB1*1501 positivity in 116 conventional multiple sclerosis (MS) patients and 101 healthy controls in a Japanese population. Logistic analysis revealed independent associations of [P] allele in the profiles for PvuII (p=0.0005, adjusted odds ratio (aOR)=3.17) and DRB1*1501 (p=0.0089, aOR=2.61) with conventional MS. Synergistic elevated risk of MS due to interaction between the [P] allele and HLA-DRB1*1501 allele was found among female patients (odds ratio=16.0; 95% CI=3.99-63.8, p<0.0001). The [P] allele-positive patients with disease duration of more than 5 years had a significantly higher progression index (PI) of disability (p=0.0230) and a worse ranked MS severity score (p=0.0152) than their non-[P] counterparts.

Adolescent↗

Familial syringomyelia: the first Japanese case and review of the literature.

We reported on syringomyelia in a mother and her son. The mother was 74-year-old, who developed gait difficulty at the age of 54. The son, 47-year-old, developed the same symptoms at the age of 35. In the both cases, MRI revealed syringomyelia with Chiari malformation. Twenty-one families with syringomyelia have been reported. The existence of these families indicates that genetic factors may play in role to the pathogenesis of this disorder.

Aged↗

Beneficial effects of tandospirone on ataxia of a patient with Machado-Joseph disease.

Tandospirone citrate (tandospirone) is an anti-anxiety drug that acts by combining with serotonin receptor (5-hydroxytryptamine-1 A [5-HT1A]). Recently, there have been a few reports of its potential role in the treatment of cerebellar ataxia. We report the first case of a patient with Machado-Joseph disease in which we successfully treated cerebellar ataxia. In addition, his leg pain, insomnia, anorexia, and depression, which are thought to be related to 5-HT1A receptors, were also remarkably alleviated by treatment with tandospirone.

Anti-Anxiety Agents↗

Effects of tandospirone on "5-HT1A receptor-associated symptoms" in patients with Machado-Josephe disease: an open-label study.

BACKGROUND: We investigated the frequencies of the symptoms such as "ataxia, depression, insomnia, anorexia, and pain," that have been reported to be associated with 5-HT1A receptor, and the effect of tandospirone citrate (tandospirone: 5-HT1A agonist) in patients with Machado-Joseph disease (MJD). METHODS: Ten MJD patients received tandospirone (15-30 mg/d) for seven weeks. During that time, they were evaluated weekly using the Ataxia Rating Scale (ARS) and Total Length Traveled (TLT) by Stabilimetry tests, the Self-rating Depression Scale (SDS), which in addition to evaluating their level of depression, also evaluated their degree of insomnia and anorexia, and a pain questionnaire. RESULTS: Before tandospirone therapy, all patients displayed cerebellar ataxia, while insomnia, and leg pain was observed in 7 patients, depression in 6 patients, and anorexia was observed in 2 patients. In response to treatment, 7 of the 10 patients who were ataxic showed a reduction in their ARS, while 3 of 6 patients showed a reduction in their SDS, and 5 of 7 patients showed an alleviation of their insomnia and leg pain. Both of the affected patients showed a marked improvement in their anorexia. A stabilimetry test could be performed in 7 patients, 5 of whom showed a reduction in TLT. CONCLUSIONS: Our data indicate that the patients with MJD are prone to manifest 5-HT1A receptor-associated symptoms, and tandospirone is a useful drug for these symptoms in patients with MJD, though a double-blind study is needed.

Adult↗