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T Yuasa

Publications and source records attributed to T Yuasa.

At least 217 records · Page 12Linked to original sources
PubMed1986

Joseph's disease: clinical and pathological studies in a Japanese family.

Joseph's disease is a hereditary ataxia found among descendants of Portuguese from the Azores Islands. We describe the clinical and pathological features of 4 members of a Japanese family who were diagnosed as having Joseph's disease. The illness began with cerebellar ataxia between the ages of 18 and 45 years. Nystagmus, dysarthria, and pyramidal signs were early manifestations. External ophthalmoplegia, dystonia and/or athetotic movements, and muscular atrophy appeared in the late stages. Neuropathological findings in one patient revealed degeneration of the dentatorubral and pallidoluysian systems, substantia nigra, pontocerebellar system, Clarke's column and spinocerebellar tracts, and anterior horn cells, as well as the cranial nuclei in the brainstem. Neurons in the inferior olivary nuclei, Purkinje's and granule cells, the cerebral cortex, thalamus, and striatum were spared. Involvement of the dentatorubral and pallidoluysian systems seems to be a characteristic feature of this disease in Japan.

Adolescent↗
PubMed1986

31P-NMR studies on an animal model of human defective muscle glycolysis.

Sequential metabolic changes in leg muscles of a model of defective muscle glycolysis that was produced by intraaortic injection of sodium iodoacetate were observed by in vivo 31P-NMR spectroscopy with a surface coil. Spectra obtained from iodoacetate-treated muscles presenting exercise-induced cramp showed decreased levels of phosphocreatinine (PCr) and adenosine triphosphate (ATP) and an accumulation of sugar phosphate. The chemical shift of inorganic phosphate (Pi) resonance, which reflects the intracellular pH of the contracted muscles, showed a milder shift to the acidic condition than those of controls. In vivo 31P-NMR study showed dynamic information on the muscle energetics under defective glycolytic conditions.

Animals↗
PubMed1986

Superoxide in ocular inflammation: human and experimental uveitis.

A possible involvement of superoxide in the pathogenesis of uveal inflammation in man and experimental animals was investigated. Superoxide production by the leukocytes of Behcet patients was significantly higher in the attack phase than in the remission phase. Leukocyte superoxide generation was also enhanced in guinea pigs with S-antigen-induced experimental autoimmune uveoretinitis (EAU). If the animals were treated with superoxide dismutase (SOD) at the onset of EAU, aqueous humor cell count was significantly lower than that of control (i.e., without SOD treatment). Infiltration of the inflammatory cells in the anterior retina was markedly reduced in SOD-treated animals. A similar protective effect of SOD against tissue damage was also observed in a bovine serum albumin-induced passive Arthus type uveitis in rabbits. These results suggest that superoxide may play a role in causing tissue damage in animal models of ocular inflammation and possibly in Behcet disease.

Animals↗
PubMed1985

Antibody to glycolipid in a patient with IgM paraproteinemia and polyradiculoneuropathy.

Serum from a patient with IgM paraproteinemia and polyradiculoneuropathy, diagnosed as malignant lymphoma reacted specifically with a lipid component in a crude ganglioside fraction isolated from human peripheral nerve, but did not react with myelin proteins including myelin-associated glycoprotein (MAG). The reactive glycolipid migrated between GM1 and GD1a gangliosides on TLC, and there was no distinct band corresponding to this glycolipid on examination with resorcinol reagent. Antibody to glycolipid in this case may play a role in the pathogenesis of neuropathy.

Aged↗
PubMed1985

Construction of nondefective adenovirus type 5 bearing a 2.8-kilobase hepatitis B virus DNA near the right end of its genome.

A novel helper-free adenovirus type 5 (Ad5) vector system, which utilizes a cloning site 0.2 kilobase (kb) from the right end of the genome, has been developed. To construct a nondefective Ad5 bearing the 2.8-kb DNA fragment of hepatitis B virus (HBV) at this site, we deleted the 2.1-kb nonessential E3 fragment from cloned DNA covering the right one-fourth of the Ad5 genome (76 to 100 map units), inserted the HBV DNA into this site, ligated the recombinant DNA to the rest of the Ad5 genome, and transfected the ligated DNA into human embryo kidney cells. Most of the recovered virus clones had only the E3 deletion and no HBV insertion, suggesting that a homologous recombination occurs between transfected DNAs in these cells. The isolated Ad5 virus bearing the HBV DNA (Ad5-HBL) grew without helper virus in HeLa cells as efficiently as wild-type Ad5, although the 1.9-kb major E4 transcript was detected only poorly in the early phase in the Ad5-HBL-infected cells, suggesting that the HBV DNA inserted upstream of the E4 promoter reduces the E4 transcript. HBV mRNAs transcribed from the inserted DNA were at least as abundant as Ad5 early mRNAs in the late phase of Ad5-HBL infection, but the HBV surface antigen was barely detectable in the infected-cell lysate and culture medium. This result suggests that HBV mRNAs can be transcribed from the inserted genes but no protein can be translated from the HBV mRNAs, presumably because of the translational suppression of cellular mRNAs caused by adenovirus in its late phase.

Adenoviridae↗
PubMed1985

Potency test of hepatitis B vaccines by the parallel line assay method in mice.

Adequate conditions for the potency test of hepatitis B (HB) vaccines in mice were looked for. Preliminary tests showed that BALB/c female mice of 5 weeks of age are adequate for the test. An immunization period of 5 weeks was found satisfactory for the test. Under these conditions, mice were immunized with each of serial dilutions of the test vaccine and a reference vaccine. The use of the parallel line assay method and the expression of the potency relative to that of the reference vaccine gave a reliable estimate of the potency of HB vaccine.

Animals↗
PubMed1985

31P-NMR studies on the energy metabolism of the living rat brain using a surface coil method.

We have examined the changes of the energetic metabolic state of rat and mouse brains under hypoxic hypoxia or ischemia using a 31P-NMR spectrometer with a surface coil. The NMR spectrometer has a super-conducting magnet providing a homogeneous magnetic field of 6.3 tesla. A probe was remodelled to accommodate an experimental animal in it. The animals were anesthetized with 1.0% or 1.5% halothane throughout the experiments. The optimal measurement conditions were a 90 degrees pulse width of 20 microsecond, and a 2 sec pulse repetition time. 200 acquisitions of FIDs was required for high spatially resolved signals. The Pcr/ATP ratio of the live, anesthetized rat brains was 1.76 +/- 0.46 (n = 8) for cerebra and 1.63 +/- 0.11 (n = 4) for cerebella. That of gerbil brains was 1.23 +/- 0.09 (n = 4). The Pcr/ATP ratio did not show any significant changes under both the conditions of hypoxic hypoxia or ischemia. The value of Pcr/Pi ratio decreased in the hypoxic conditions. The level of Pcr. of rat cerebrum decreased by 76.8 +/- 10.5% at 10% oxygen and by 57.3 +/- 15.7% at 5% oxygen compared with the value of 20% oxygen. The ATP level in the rat brain also decreased according to the degree of hypoxia. Cerebral ischemia was produced in the gerbil by ligation of the common carotid artery. The levels of Pcr. and ATP were severely depressed in the ischemic hemisphere but those of the intact side remained normal.

Adenosine Triphosphate↗
PubMed1984

Adrenoleukodystrophy: a clinical variant presenting as olivopontocerebellar atrophy.

A case of adrenoleukodystrophy showing neurological features of olivopontocerebellar atrophy is described. A CT scan demonstrated marked atrophy in both cerebellum and pons. ACTH stimulation produced no rise in the plasma cortisol level but a significant rise in the plasma aldosterone level. The ratios of C26:0 to C22:0 in fatty acids of sphingomyelin from erythrocyte membrane and plasma were increased.

Adrenocorticotropic Hormone↗
PubMed1984

Determination of hepatitis B virus DNA in serum by molecular hybridization.

Hepatitis B virus (HBV) DNA was detected by direct spotting of alkali-denatured serum on a nitrocellulose filter and molecular hybridization with cloned HBV DNA as the probe. Measurement of the autoradiographic signals as the intensity of hybridization allowed the quantitation of HBV DNA content in serum specimens in reference to cloned HBV DNA. Direct spotting of denatured serum was approximately three times as sensitive as the conventional method in which proteinase-treated serum was extracted with phenol-chloroform. The intensity of hybridization with 25 specimens of HB virion concentrates correlated well with DNA polymerase activity (r = 0.89, P less than 0.01).

Cloning, Molecular↗
PubMed1984

Neutrophil collagenolytic activity in patients with Behçet disease.

Studies were made on neutrophil dysfunction in Behçet disease by examining collagenolytic activity in neutrophils. The collagenolytic activity of neutrophil was found to be significantly higher in patients during the attack phase of this disease than in patients during the remission phase, in patients with other forms of uveitis and in normal controls. Collagenase was present in the collagenolytic enzyme, which showed high activity in the attack phase. The molecular weight of this enzyme was similar to that of mammalian neutrophil collagenase.

Adult↗