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Ryohji Nakamura

Publications and source records attributed to Ryohji Nakamura.

4 recordsLinked to original sources
PubMed2005

Harmful effects of anti-GalNAc-GD1a antibodies and TNF-alpha on rat dorsal root ganglia.

The clinical characteristics of five (22%) of 23 patients with Guillain-Barré syndrome (GBS), whose serum contained immunoglobulin G (IgG) antibodies to the ganglioside N-acetylgalactosaminyl GD1a (GalNAc-GD1a), included pure motor weakness of the axonal type. These patients had a relatively good prognosis, but displayed higher serum tumor necrosis factor-alpha (TNF-alpha) titers than the other GBS patients. We examined the effect of serum from these patients with IgG anti-GalNAc-GD1a antibodies on neurites from cultured rat dorsal root ganglia (DRG) and found it to damage the myelin in well-elongated DRG neurites and monolayer cultures of Schwann cells and neurons. In the regeneration model, serum from these patients delayed neurite extension and inhibited Schwann cell proliferation. Neurons in cultured monolayers showed vacuolation and decreased rapidly in number. Schwann cells were also vacuolated and readily detached from the substratum. The effects of IgG anti-GalNAc-GD1a antibodies purified from one of the patients, rabbit serum after immunization with GalNAc-GD1a, and recombinant TNF-alpha were also examined. IgG anti-GalNAc-GD1a antibodies mainly inhibited the regeneration and preservation of neurons, while TNF-alpha mainly induced morphological changes in well-proliferated Schwann cells and myelin.

Adolescent↗
PubMed2004

Therapeutic factors causing hallucination in Parkinson's disease patients, especially those given selegiline.

Selegiline protects nigral dopaminergic neurons and is recommended for the treatment of patients in the early stage of Parkinson's disease (PD). We treated 112 PD patients and noted that those given selegiline had a high incidence of hallucination. Our objective was to determine which clinical therapeutic factors cause such hallucinations. The Kruskal-Wallis and chi-square test showed that in 94 patients, the severity of the hallucinations was significantly related to the duration of illness, Hoehn and Yahr stage, doses of levodopa and cabergoline, whether or not selegiline was used, and whether or not medication for constipation was required. In addition, patients who were treated with a low dose of levodopa (< or =300 mg/day), who had a low Hoehn and Yahr stage, and a short duration of illness (< or =8 years) together with a high dose of selegiline or cabergoline also tended to have hallucinations. MRI findings were not related to the incidence of hallucination. When selegiline is given to patients who have PD of long duration and a high Hoehn and Yahr stage, and who already are receiving levodopa and a dopamine agonist, the doses of levodopa and the dopamine agonists given, as well as the presence of constipation, may be related to the incidence of hallucination.

Adult↗
PubMed2002

Motor dominant neuropathy in Sjögren's syndrome: report of two cases.

Most of the peripheral neuropathies in Sjögren's syndrome (SS) are sensory- or autonomic-dominant. In this report, we present two cases of a rare type of neuropathy, motor dominant neuropathy, in SS. One showed signs similar to those of Guillain-Barré syndrome, and the other showed signs characteristic of chronic inflammatory demyelinating polyradiculoneuropathy. These patients received i.v. immunoglobulin therapy. To our knowledge, this is the first report indicating that i.v. immunoglobulin has beneficial effects on motor dominant neuropathy in SS.

Aged↗