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Hiroyuki Soma

Publications and source records attributed to Hiroyuki Soma.

5 recordsLinked to original sources

MSA-C is the predominant clinical phenotype of MSA in Japan: analysis of 142 patients with probable MSA.

We investigated the clinical features and mode of disease progression in 142 patients with probable multiple system atrophy (MSA) according to the Consensus Criteria. The subjects included 84 men and 58 women with a mean age at onset of 58.2+/-7.1 years (range: 38-79 years). Cerebellar signs were detected in 87.3% of these patients at the time of initial examination, and were found in 95.1% of them at latest follow-up. MSA-C was diagnosed in 83.8% of the patients at their first examination. Parkinsonism was initially detected in 28.9% of the patients, increasing to 51.4% at the latest follow-up. Among all of the subjects, only 16.2% were classified as having MSA-P on initial examination. At the latest follow-up, parkinsonian features had become predominant over cerebellar features in 24.6% of the 65 patients with MSA-C who were followed for more than 3 years. Although parkinsonism usually masked the signs of cerebellar involvement in MSA-C patients, none of the patients with MSA-P at an early stage showed predominance of cerebellar features at the latest follow-up. Parkinsonism is the predominant feature of MSA among Western patients, even at an early stage, but this study showed that cerebellar deficits are the main feature in Japanese patients. This difference of disease manifestations between ethnic groups suggests that genetic factors may influence the clinical phenotype of MSA.

Adult↗

Four mutations of the spastin gene in Japanese families with spastic paraplegia.

Hereditary spastic paraplegia (HSP) is a group of genetically heterogeneous neurodegenerative disorders characterized by slowly progressive spasticity and weakness of the lower limbs. HSP is caused by failure of development or selective degeneration of the corticospinal tracts, which contain the longest axons in humans. The most common form of HSP is caused by mutations of the spastin gene (SPAST), located on chromosome 2p21-p22, which encodes spastin, one of the ATPases associated with diverse cellular activities (AAA). In this study, we detected four causative mutations of SPAST among 14 unrelated patients with spastic paraplegia. Two missense mutations (1447A-->G, 1207C-->G) and two deletion mutations (1465delT, 1475-1476delAA) were located in the AAA cassette region. Three of these four mutations were novel. Previous reports and our results suggest that the frequency of SPAST mutations is higher among Japanese patients with autosomal dominant HSP, although SPAST mutations are also observed in patients with sporadic spastic paraplegia.

Adenosine Triphosphatases↗

Heredity in multiple system atrophy.

We investigated the family histories of 157 Japanese patients with probable or possible multiple system atrophy (MSA). A family history of neurodegenerative disorders was only detected in three MSA patients (1.9%). We evaluated these patients by careful neurological examination, neuroimaging studies, and genetic studies to exclude hereditary spinocerebellar ataxia with a similar clinical phenotype to MSA. The results indicated that one of them had a family history of MSA. Although the familial presence of neurodegenerative disorders is rare in MSA patients, the existence of such cases suggests that MSA may have a genetic background.

Adult↗