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Biomedical subjects

T Tsubaki

Publications and source records attributed to T Tsubaki.

At least 91 records · Page 5Linked to original sources
PubMed1980

Rimmed vacuoles.

Rimmed vacuoles (Dubowitz and Brooke 1973) have been found in 12 cases with various neuromuscular diseases and are considered to be autophagic in nature. They consisted of multilaminated membranous structures accompanied by glycogen granules, dense bodies, and amorphous, granular, and fibrillar material. The contents of the vacuoles were regarded as having partially dissolved out of the vacuoles in cryostat sections but some were plastered along the walls of the vacuoles and were depicted by the staining procedures for light microscopy. The "lined vacuoles" described by Carpenter et al. (1978) in inclusion body myositis closely agree with the rimmed vacuoles in respect of histochemical and ultrastructural features.

Adolescent↗
PubMed1980

Myoclonus epilepsy associated with ragged-red fibres (mitochondrial abnormalities ): disease entity or a syndrome? Light-and electron-microscopic studies of two cases and review of literature.

A report is given of an association of dyssynergia cerebellaris myoclonica associated with Friedreich's ataxia and mitochondrial myopathy in 2 patients. They had suffered from gradually increasing bursts of myoclonus since the wage of 14 and childhood, respectively. The other striking clinical features included generalized convulsions, mental deterioration, intention tremor, ataxia, muscular atrophy and deformity of feet. Muscle biopsies revealed ragged-red fibres in both cases. On electron microscopy these fibres contained subsarcolemnal aggregations of abundant abnormal mitochondria with proliferation of inner membranes or paracrystalline inclusions. One of these patients showed elevated blood lactate and pyruvate with an increased lactate/pyruvate ration, apparently of primary origin. These 2 cases resemble those reported briefly by Tsairis et al. (1974). An association of dyssynergia cerebellaris myoclonica associated with Friedreich's ataxia and mitochondrial myopathy in these 2 patients is unlikely to be coincidental but may represent one nosological entity. This myoclonus epilepsy syndrome associated with ragged-red fibres is compared with other possibly related mitochondrial encephalomyopathies.

Adult↗
PubMed1979

Endocrinologic regulation of carbohydrate metabolism. Amyotrophic lateral sclerosis and Parkinsonism-dementia on Guam.

Studies of the endocrinologic control of carbohydrate metabolism were conducted in Guamanians with parkinsonism-dementia (PD) or amyotrophic lateral sclerosis (ALS) and in Guamanian control patients who had various other neuromuscular disorders. Intravenously infused arginine tended to produce a more prolonged elevation in serum glucose levels in PD and ALS patients than in control subjects. On the other hand, the serum insulin response to arginine was significantly less in both PD and ALS patients than in controls. Arginine stimulated the release of growth hormone to a similar degree in all three patient groups. These observations support and extend previous reports of endocrinologic abnormalities in parkinsonism and ALS and might suggest that a defect in pancreatic islet cell function attends these disorders.

Adult↗
PubMed1979

Slow cord dorsum potentials elicited by descending volleys in man.

Human cord dorsum potential (CDP) was recorded from the posterior epidural space at the levels of cervical and lumbar enlargements, using epidural catheters as the recording electrodes, in 15 normal volunteers and six patients suffering from amyotrophic lateral sclerosis. In normal subjects the CDP elicited by descending volleys consisted of spike potentials followed by sharp negative and slow positive waves which were very similar to the P1, N1, and P2 potentials, respectively, of the CDP evoked segmentally. By contrast, in all patients with amyotrophic lateral sclerosis both the sharp negative and slow positive waves were absent in the CDP elicited by descending volleys, while the pattern of each component of the segmentally evoked CDP remained unchanged. Thus, the sharp negative and slow positive waves of human CDP elicited by descending volleys might reflect the activity of interneurones and primary afferent depolarisation respectively, produced by impulses through the corticospinal tract.

Adult↗
PubMed1978

Nemaline myopathy: histological, histochemical and ultrastructural studies.

Histological, histochemical and ultrastructural studies were performed on muscle biopsies from three siblings with congenital nemaline myopathy. Histological studies revealed type I fibre atrophy and type II fibre paucity. Ultrastructural studies of intramuscular nerves showed that the axonal diameters were very narrow compared with the width of myelin lamellae. Granular or membranous osmiophilic material occurred in the adaxonal Schwann cell cytoplasm and had a periodicity of 33--38 A. The neuromuscular junctions showed degenerative features such as glycogen granules or myelin figures in 27.1% of total terminal axons. The secondary synaptic clefts were markedly decreased in number and short in length. Myotendinous junction-like structures were found in 5.5% of the muscle fibres near the neuromuscular junctions, and often near sites of fibre-splitting. Rods in nemaline myopathy might be caused as a result of longitudinal splitting and disruption of fibres due to deficient regeneration of the muscle fibres associated with neurotrophic abnormalities.

Adolescent↗
PubMed1978

Binding of iodine 125 alpha-bungarotoxin to the thymus of mice.

alpha-Bungarotoxin is known to bind with nicotinic acetylcholine receptors of skeletal muscle. Binding of iodine 125-labeled alpha bungarotoxin to the murine thymus, muscle, and liver was estimated. The toxin was bound to the muscle. The thymus was also capable of binding a considerable amount of the toxin, and the binding was obviously blocked by tubocurarine chloride. Binding to the liver, an organ containing no nicotinic acetylcholine receptor, was very slight. These results may indicate the presence of nicotinic acetylcholine receptors in the thymus, which could have implications in the pathogenesis of myasthenia gravis. Degenerating myoid cells and their receptors may represent autoantigens that induce an immunological cross-reaction with the receptors of skeletal muscles, giving rise to myasthenia gravis.

Acetylcholine↗
PubMed1978

HLA and Japanese MS.

Determination of HLA-A, -B and -C types in 43 Japanese patients with multiple sclerosis (MS) and of DR type in 25 MS patients was carried out using antisera from the 7th International Histocompatibility Workshop. The results were compared with 46 controls typed simultaneously. Twenty-three patients were also tested for HLA-Dw2. The conclusions were: 1) There were no significantly higher occurrences of HLA-A3, B7, Dw2 or DRw2 in Japanese MS. 2) Japanese MS might nevertheless be associated with the human major histocompatibility complex, because HLA-B40 was significantly less frequent in MS and two anti HLA-DRw sera, 7w008 and 034, reacted positively more often against lymphocytes from MS patients.

Epitopes↗
PubMed1977

Changing mortality patterns of motor neuron disease in Japan.

The age-adjusted female death rate from motor neuron disease in Japan was noted to rise after 1952 and to fall rapidly since about 1960. A similar trend was also noticed in the males. Further study will show whether this was a part of a cyclical change or whether the mortality of the disease has entered a period of prolonged decline in that country. Death rates for neurological diseases in various countries were reported previously for 1953-58. Updating this study for 1966-71, a rising trend of deaths from motor neuron disease was identified in European countries, but the rate has been stationary in the United States. The rapidly changing patterns of the mortality seemed incompatible with a purely genetic causation of the disease. This indicates the need for extensive epidemiological studies to identify the extrinsic factors which induced such a trend, and were thus possibly the cause of the disease. In view of the results of the re-evaluation of the diagnosis in death certificates, mortality figures of motor neuron disease in females appeared reasonably reliable for an epidemiological study.

Adolescent↗