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Biomedical subjects

K Miyoshi

Publications and source records attributed to K Miyoshi.

At least 235 records · Page 13Linked to original sources
PubMed1980

Solid-phase synthesis of polynucleotides: V. Synthesis of oligodeoxyribonucleotides by the phosphomonotriazolide method.

Synthesis of two oligodeoxyribonucleotides of defined sequences, an undecamer [d(TGCACCATTCT)] and a dodecamer [d(TGGAGCCACTAT)], and tetradecathymidylic acid was described by a simple solid-phase method on a polystyrene resin. The synthesis was performed by the stepwise addition of deoxynucleoside 3'-phosphomonotriazolide to the resin, in the presence of a nucleophilic catalyst, 4-dimethylaminopyridine or N-methylimidazole. Quantitative coupling yield was consistently obtained for each cycle and the desired product was a major peak in the analysis of the final reaction by high performance liquid chromatography on Permaphase AAX.

Base Sequence↗
PubMed1979

Studies of metallobleomycins by electronic spectroscopy, electron spin resonance spectroscopy, and potentiometric titration.

The 1:1 bleomycin-A2-Cu(II) complex shows an absorption maximum at 595 nm (epsilon 120), circular dichroism extrema at 555 nm (delta epsilon + 1.21) and 665 nm (-0.61), and electron spin resonance (ESR) signal with g = 2.211, g = 2.055, and A = 178 x 10(-4) cm-1. The formation constant (log K = 12.630) and deprotonation constant (PKc = 3.585) of the 1:1 bleomycin-Cu(II) complex were determined by computer analysis of potentiometric data. The results of potentiometric titration also indicate that the stability of bleomycin-metal complexes is in the order Fe(II) less than Co(II) less than Ni(II) less than Cu(II) greater than Zn(II) and that these divalent metal complexes have a similar coordination environment. The bleomycin-Cu(II) complex has substantially a square-pyramidal configuration in which the secondary amine nitrogen, pyrimidine(N-1) ring nitrogen, deprotonated peptide nitrogen of histidine residue, and histidine imidazole(N-1) nitrogen coordinate to Cu(II) as planar ligand donors, and the alpha-amino nitrogen as axial donor. The specific Cu(II)-binding site of bleomycin has been compared with that of human serum albumin.

Binding Sites↗
PubMed1978

Rapid, sensitive detection of myoglobulinemia by improved counterimmunoelectrophoresis in cases of acute myocardial infarction.

A counterimmunoelectrophoresis technique for detection of serum myoglobin (Mb) was improved using non-ionic polymer dextran. Precipitin lines were graded according to their strength, which was ascertained by radioimmunoassay data. By this method, serum Mb in concentrations of 500 ng./ml. before stain and of 200 ng./ml. after stain were detected. Electrophoretic time was 60 minutes. Among 32 cases of acute myocardial infarction (AMI) whose blood samples were collected within 24 hours after disease onset, precipitin lines were detected in 25 cases (78%) before stain and 31 cases (97%) after stain. Considering the early peak concentration time (approximately 10 hours) of serum Mb after AMI onset, diagnosis becomes more rapid and exact with this method, especially in severe cases.

Acute Disease↗
PubMed1978

Abnormal expression of a serine protease in human dystrophic muscle.

The activities of serine protease in muscles from normal persons and from patients with progressive muscular and neuromuscular diseases have been determined. A significant increase in the level of serine protease was found in muscle of patients with Duchenne-type muscular dystrophy and with Becker-type muscular dystrophy, but the activity was not increased in muscle of a patient with amyotrophic lateral sclerosis.

Adult↗
PubMed1978

Experimental spongy degeneration of the white matter induced by 6-aminonicotinamide intoxication.

Spongy state and degeneration of the white matter in the 6-aminonicotinamide intoxicated rats were studied neuropathologically and electromicroscopically. Young albino rats, four weeks of age, received 0.1% of 6-aminonicotinamide solution intraperitoneally as a single dose of 10 mg/Kg of body weight. Four hours after the administration, paralysis of the hind limbs occurred in the rats. Neuropathological investigations revealed a characteristic spongy and degenerative change of white matter as well as gray matter of the central nervous system. Corpus callosum, cerebellar cortex, and optic nerves showed edematous and spongy degeneration in the early stage of the experiment. Ultrastructural changes of myelin sheath were initially seen in the vicinity of severely damaged oligodendrocytes. The vacuoles in the myelin, i.e. intramyelinic vacuoles, were formed by splitting between the innermost myelin lamellae and axon. Axons remained usually unchanged in the early stage. The pathogenesis of ultrastructural changes of the white matter in the 6-aminonicotinamide intoxication was discussed.

6-Aminonicotinamide↗
PubMed1978

Radioimmunoassay for human myoglobin: methods and results in patients with skeletal muscle or myocardial disorders.

A sensitive and specific radioimmunoassay has been developed for the measurement of serum Mb. immunization of rabbit with human Mb yielded anti-Mb antibody which was purified by affinity chromatography. Human hemoglobin, CK, and the component of serum per se did not appear to cross-react with the antibody. Mb was radiolabeled by the chloramine T method. The radioimmunoassay method could detect as little as 0.3 ng of Mb and was not affected by hemolysis. Information is also given on precision, recovery, and specimen preservation. Mb levels could be detected in all of 120 normal adults, and the values ranged between 1 and 28 ng/ml (mean, 13.1 +/- 6.1). No sex difference was observed. Levels were markedly elevated in all the patients with progressive muscular dystrophy, especially in the Duchenne type at the level of 40 to 1700 ng/ml. It was also noticed that about 70% of female gene carriers of Duchenne type had a slightly increased Mb level. An elevated serum Mb was also noted in polymyositis. In every case of acute myocardial infarction, serum Mb levels were increased, peak values ranging from 175 to 4400 ng/ml and averaging 1162 +/- 287.9. Mb levels were elevated faster and peaked earlier (within 6 to 12 hr after the attack) than serum CK activity and returned to nearly normal range within 3 to 4 days. The increase in serum Mb was also noticed in shock and surgery. These data indicate that radioimmunoassay of Mb is a useful test for judging the myolytic state of myogenic myopathies and for early detection of myocardial infarction.

Creatine Kinase↗
PubMed1977

Chronic tellurium intoxication in rats.

(1) Accumulation of neuronal lipofuscin was clearly demonstrated in the chronic tellurium intoxication in young rats with histological, fluorescent and electron-microscopical methods; (2) The needle-shaped crystal in the neuronal lysosomes were demostrated to contain the tellurium with electron dispersive spectrophotometry analysis. (3) The vacuolation of the cytoplasm of Schwann cells was the initial pathological change noted in the tellurium peripheral neuropathy.

Animals↗
PubMed1977

Polygraphic study of periodic breathing and hypersomnolence in a patient with severe hypothyroidism.

A 67-year-old woman with primary hypothyroidism, who had Pickwickian syndrome as well, was studied electrophysiologically. A polygraphic study with simultaneous recordings of electroencephalography, actograms of the abdominal walls, the mentum and the anterior neck, and electromyogram of the intercostal muscles revealed a cyclic appearance of apnea in the sleep phase and gasping preceding arousal, which, together with macroglossia and sleep in the sitting position, suggested a cyclic obstruction of the upper airway. The obstruction appeared responsible for both alveolar hypoventilation and disturbance of consciousness.

Aged↗