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T Yuasa

Publications and source records attributed to T Yuasa.

At least 163 records · Page 9Linked to original sources
PubMed1993

[Distribution of nitric oxide synthase activity in rat brain--analysis by high performance liquid chromatography].

As a basic study to investigate the involvement of nitric oxide in the pathogenesis of central nervous system diseases, we have established an assay system to measure nitric oxide synthase (NOS) activity by a high performance liquid chromatography monitoring conversion of arginine into citrulline. NOS activity in the rat brain was calcium-dependent and inhibited by L-nitro-arginine, a specific NOS inhibitor. The activities in the discrete brain regions were in the order cerebellum > olfactory bulb > striatum > hippocampus > cerebral cortex > midbrain > hypothalamus > pons.

Amino Acid Oxidoreductases↗
PubMed1993

Protective actions of YM737, a new glutathione analog, against cerebral ischemia in rats.

Effects of YM737[N-(N-r-L-glutamyl-L-cysteinyl)glycine 1-isopropyl ester sulfate monohydrate], a new glutathione (GSH) analog more readily transported into cells than GSH, on cerebral ischemia were compared with those of GSH and some other drugs in rats subjected to occlusion of the bilateral carotid arteries. YM737 significantly reduced lethality, increased brain-water levels as measured by both dry-wet and NMR methods, and increased malondialdehyde (MDA) levels in the cerebral ischemic rats. On the other hand, pharmacological actions of GSH itself was less than those of YM737. In the ischemic rats used in the present study, there was no significant difference in 31P-NMR signals between the normal and the cerebral ischemic rats. These results suggest that YM737 showed anti-cerebral ischemic effects presumably due, in part, to inhibition of lipid peroxidative responses.

Animals↗
PubMed1993

[A sporadic case of late onset familial amyloidotic polyneuropathy preceded by cardiac involvement].

We report a 65-year-old man with amyloidotic polyneuropathy, who first suffered from heart failure at the age of 57, 3 years before the onset of neurological symptoms. He had no obvious family history. We analysed the transthyretin gene of the patient and 6 asymptomatic family members using polymerase chain reaction (PCR). The single amino acid substitution of a methionine for valine at position 30, which is a common mutation of Japanese type I FAP patients, was found from the patient and his sister of 47 years. Though Type I FAP patients often have cardiac conduction block, they rarely have signs of heart failure until the end stage of the disease. This is the first report of Type I FAP with severe myocardial involvement, in which TTR mutation at position 30 was confirmed. The result revealed the clinical variation of Type I FAP.

Aged↗
PubMed1993

[Visualization of brain function using MRI-MR functional brain imaging].

The effects of photic stimulation on the visual cortex of human brain were studied by means of gradient-echo magnetic resonance imaging (MRI). Fast low-angle shot (FLASH) MRI was used to monitor changes in brain oxygenation in the human visual cortex during photic stimulation (PS). Whole-body 1.5 T clinical MR system was used. Elevation of image intensity up to 2% was observed in primary and associative visual cortex, corresponding to an increase of blood oxygenation in regions of increased neural activity. After the PS was switched off, the MR signal fell below the pre-PS baseline level, which may be understood as an displacement of the oxygen-hemoglobin dissociation curve (the Bohre effect).

Adult↗
PubMed1993

[Hereditary dentatorubro-pallidoluysian atrophy (DRPLA): clinical studies on 45 cases].

The term of dentatorubral and Pallidoluysian atrophy (DRPLA) was first introduced by Smith, who proposed that there was a combination of cerebellar ataxia with choreoathetosis based on DRPL lesions. In 1972, Naito et al. reported two families with progressive myoclonus epilepsy (PME) syndrome with cerebellar ataxia, and hyperactive deep tendon reflexes. In 1977, Oyanagi et al. reported 4 autopsied cases of PME, and pointed out degenerative lesions in the DRPL systems. In 1982, Naito and Oyanagi reported this type of PME to be hereditary DRPLA, with a clinicopathological disease entity. This type of PME with DRPLA has been made a major category, especially in Japan. In this article, clinicopathological features of the hereditary DRPLA will be reviewed on the basis of 45 patients with this disease. The disease was inherited as an autosomal dominant fashion, and induces a wide rage of clinical features depending upon the age of onset, ranging from 3 years to 69 years of age. The initial symptoms were variable according to the age of onset and mental retardation was the most prominent symptom in the patients in which the disease started in the first decade and with an epileptic seizure in the second decade. In the following next two decades, the incidence of epileptic seizure, as initial symptoms was decreased to 23% and gait disturbance and ataxia in 38% of the patients, which increased to 73% in the 5th and 6th decades. The cardinal symptoms of hereditary DRPLA includes mental retardation, epileptic seizure and myoclonus, cerebellar ataxia with gait disturbances, psychological symptoms including clonus, cerebellar ataxia with gait disturbances, psychological symptoms including character changes, and dementia.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1993

[MRI findings of olivopontocerebellar atrophy and Machado-Joseph disease--diagnostic value of transverse pontine fibers].

Olivopontocerebellar atrophy (OPCA) and Machado-Hoseph disease (MJD) occasionally show similar clinical signs and symptoms, which makes differential diagnosis of OPCA and MJD difficult. In 1990, Savoiardo et al. reported that the transverse pontine fibers of OPCA patients had high signal intensity on T2 weighted MR images. To determine if the high signal intensity of the transverse pontine fibers is useful for the differential diagnosis of OPCA and MJD, we examined this abnormal intensity in patients diagnosed as OPCA or MJD. We observed the high intensity of transverse pontine fibers in all of the 18 OPCA patients. This finding, however, was not observed in any of the patients with the MJD. The high signal intensity of the transverse pontine fibers in T2 weighted images is characteristic of OPCA patients. Furthermore the atrophy of pontine tegmentum is characteristic of patients with MJD. These findings correlate well with pathological findings of OPCA and MJD, indicating the usefulness of these MRI findings for the differential diagnosis of OPCA and MJD.

Adult↗
PubMed1993

[A case of allergic bronchopulmonary candidiasis improved with steroid inhalation].

A 49-year-old woman was admitted to hospital because of productive cough and dyspnea. She had been well two months before admission, when she developed an attack of asthma. Chest roentgenogram taken on admission revealed numerous shadows of inhomogeneous density in both lungs. Laboratory findings showed leukocytosis with eosinophilia (25%), high IgE level in serum and positive RAST score to Candida albicans. A diagnosis of allergic bronchopulmonary candidiasis was made by these laboratory data and clinical course. The patient was treated successfully by oral administration of methylprednisolone and inhalation of amphotericin B, but she had a relapse of the disease on cessation of steroid medication. Inhalation of beclomethasone dipropionate and procaterol hydrochloride was commenced. Thereafter, pulmonary infiltration and clinical symptoms improved after three weeks.

Administration, Inhalation↗
PubMed1992

Ca(2+)-dependent protein kinase from the halotolerant green alga Dunaliella tertiolecta: partial purification and Ca(2+)-dependent association of the enzyme to the microsomes.

Ca(2+)-dependent protein kinase (CDPK) was purified 900-fold from the soluble fraction of Dunaliella tertiolecta cells by ammonium sulfate precipitation, DEAE-Toyopearl, phenyl-Sepharose, and hydroxylapatite column chromatography. The CDPK was activated by micromolar concentration of Ca2+ and required neither calmodulin nor phospholipids for its activation. The enzyme phosphorylated casein, myosin light chain, and histone type III-S (histone H-1), but did not phosphorylate protamine and phosvitin. The Km values for ATP and casein were 11 microM and 300 micrograms/ml, respectively. Phosphorylation of casein was inhibited by calmodulin antagonists, calmidazolium, trifluoperazine, and compound 48/80, but not affected by calmodulin. CDPK bound to phenyl-Sepharose in the presence of Ca2+ and was eluted by ethylene glycol bis(beta-aminoethyl ether) N,N'-tetraacetic acid (EGTA). This suggests that hydrophobicity of the enzyme was increased by Ca2+. CDPK was also bound to the microsomes isolated from Dunaliella cells in the presence of micromolar concentration of Ca2+ and released in the presence of EGTA, suggesting the possibility of in vivo Ca(2+)-dependent association of the enzyme. The enzyme phosphorylated many proteins in the microsomes but few in the cytosol, if at all.

Calmodulin↗
PubMed1992

[A hereditary ataxia associated with hypoalbuminemia and hyperlipidemia--a variant form of Friedreich's disease or a new clinical entity?].

The patients belonged to three different families and were products of consanguineous marriage. The neurological symptoms and signs in these patients began in infancy or childhood and included gait disturbance, horizontal nystagmus, distention tremor of the hands, muscular wasting and sensory impairment of the hands and legs. CT-scan and/or MRI showed atrophy of the cerebellum. Serum biochemical analyses revealed hypoalbuminemia with hyperlipidemia. There were no abnormalities in the heart, liver, kidney, gastrointestinal tract, or endocrine systems. The autopsy revealed degenerative changes in the spinal cord including posterior column and lateral pyramidal tract, as well as in the peripheral nerves and cerebellar cortex. Although we have speculated that the disease presented here would be a clinical variants of Friedreich's disease, it would make a new clinical entity because there was no report about the association to hypoalbuminemia and hyperlipidemia with spinocerebellar degeneration.

Adult↗
PubMed1992

[Primary effect of preoperative intra-arterial infusion chemotherapy in cervical cancer].

In order to obtain better prognoses for cervical cancer, we conducted preoperative intra-arterial (i.a.) infusion chemotherapy of CDDP in combination with AT-II pressor. Two courses of i.a. chemotherapy were performed for 67 patients with cervical cancer in stage IIb containing 54 squamous cell carcinomas and 13 adenocarcinomas before operation every 3 weeks. A histologically desirable effect in cervical lesion was obtained. A group given preoperative i.a. chemotherapy had a significantly lower rate of infiltration beyond uterus in comparison with 156 patients with 145 squamous cell carcinomas and 11 adenocarcinomas treated by surgery alone as the control group. Further, the rate of histological infiltration to parametrial edges after i.a. chemotherapy tended to be lower than the control group. From the above, it was considered that preoperative i.a. infusion chemotherapy of CDDP in combination with AT-II pressor for cervical cancer was effective as a neo-adjuvant chemotherapy.

Adenocarcinoma↗
PubMed1992

[Extrapleural approach for patent ductus arteriosus and coarctation of the aorta].

During the period of 1989 to 1990, 6 consecutive children with patent ductus arteriosus or coarctation of the aorta underwent operative therapy. Ligation or division of patent ductus arteriosus or subclavian flap angioplasty for coarctation of the aorta were performed by extrapleural approach with axillary or posterolateral incision. Patients' ages ranged from 9 days to 8 years. Weights ranged from 3 to 30 kg. It was very easy to have better operative field and beneficial to protect the lung against mechanical injury. Extrapleural approach was not so easy in an 8-year-old patient with firm connective tissue. Therefore, this procedure is considered to be suitable for younger children.

Aortic Coarctation↗
PubMed1992

[Hereditary dentatorubropallidoluysian atrophy--clinical variants in a family and degeneration of cerebral white matter in a proband].

We describe a family with hereditary dentatorubropallidoluysian atrophy (DRPLA). 4 patients through 3 successive generations showed a wide clinical variety. The female proband with onset in the elderly developed choreiform involuntary movement, dementia, hyperreflexia and, at the progressive stage, mild ataxia. However she had never displayed epilepsy and myoclonus. The 2 sons showed dementia, choreoathetoid movement and ataxia. The grandson developed typical signs and symptoms of progressive myoclonus epilepsy. The brain CT in the proband showed severe cerebellar and brain stem atrophy, moderate cerebral cortical atrophy and diffuse low density lesions in the deep cerebral white matter. Her neuropathological examination revealed the atrophy and gliosis of cerebral and cerebellar white matter concomitant with both dentatorubral and pallidoluysian system degeneration. The present study indicates that hereditary DRPLA can include multiple clinical variants even in the same family and the degeneration of cerebral and cerebellar white matter besides dentatorubral and pallidoluysian system.

Adolescent↗
PubMed1992

[Staged sternal closure for the case of postoperative severe cardiac failure: a convenient method in the intensive care unit].

A convenient method of staged sternal closure in the intensive care unit for a patient with severe cardiac failure was reported. According to the patient's cardiac function, optimal intersternal space can be adjusted. When using this method on a infant, the adjustment has shown to be very easy and take only a short time. However we have no experience on adults with stronger sternum.

Cardiac Output, Low↗
PubMed1992

[Carpentier's procedure for Ebstein's anomaly: successful and failed cases].

Two adult cases of Ebstein's anomaly underwent Carpentier's procedure. In the first case longitudinal plication limited to free wall of atrialized ventricle was performed and postoperative course was uneventful. In the second case preoperative echocardiography showed apparently restricted movement of anterior leaflet of the tricuspid valve which was compatible with intraoperative findings. That is, inferior edge of anterior leaflet was partly adherent to ventricular wall and systolic bulging of leaflet was significantly impaired which was left untouched but should be repaired by additional procedure. Six days after operation the tricuspid valve replacement was required for persistent right heart failure due to residual tricuspid regurgitation. In the same case longitudinal plication of atrialized ventricle reported by Carpentier and colleagues resulted in excessively small annulus. Therefore we had to reduce the plication and did not perform following atrial plication to avoid direct injury to conduction system or disturbing coronary venous return. In conclusion exact preoperative evaluation of anterior leaflet of the tricuspid valve especially subvalvular anatomy is essential to Carpentier's procedure, as Carpentier and colleagues emphasized, and conservative longitudinal plication of the atrialized ventricle limited to free wall is favorable when excessively small annulus might be concerned.

Cardiac Surgical Procedures↗
PubMed1992

[An acute axonal polyneuropathy affecting intrinsic hand muscles following Campylobacter infection--a case report].

A 24-year-old carpenter had the shakes and fever on March 13, 1990. He suffered from watery diarrhea on March 14 and 15. He left muscle weakness in his thumbs and fingers when he drove nails with a hammer on March 24. The weakness reached maximum by the 3rd day of illness. He was admitted to our hospital on day 4. Neurological examination revealed symmetrical weakness localized in the intrinsic hand muscles (MRC grade 2-4). The deep tendon reflexes were preserved. Sensation was intact except for mild disturbance of superficial sense on both plantar areas. Campylobacter jejuni was cultured from his stool. A complement fixation test indicated serologically preceding C. jejuni infection. Whereas maximum motor nerve conduction velocities were not reduced and distal latencies were not prolonged, compound muscle action potential recorded in the thenar and hypothenar muscles were remarkably reduced on day 5. Needle EMG showed neuropathic changes in four limbs. Sensory nerve conduction velocities and action potentials were normal. The weakness gradually improved in association with increased compound muscle action potentials in the thenar and hypothenar muscles. His muscle symptom fully resolved 2 months after the onset of his illness. Thin-layer chromatogram with immunostaining revealed that serum IgG from this patient reacted with GM1, GD1a, GD1b, but did not react with GM2 and GT1b. Enzyme-linked immunosorbent assay showed that anti-GM1, GD1a, GD1b antibodies titer (IgG) decreased concurrently with the clinical improvement.

Acute Disease↗