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T Otonari

Publications and source records attributed to T Otonari.

3 recordsLinked to original sources

Two cases of schwannoma with marked cystic changes.

We report two cases of schwannoma displaying marked cystic changes; one in the temporalis muscle and one in the submandibular space. The first patient, a 44-year-old male, presented after complaining of a swelling rapidly increasing in size in the left temporal region. Computed tomography (CT) indicated a low-density area surrounded by soft tissue. Magnetic resonance imaging (MRI) revealed signal hypointensity on T1 weighted imaging and strong signal hyperintensity on T2 weighted imaging. The extirpated tumour specimen measured 58 mm x 58 mm x 30 mm. Histopathological examination identified schwannoma, comprising spindle cell proliferation in a palisading pattern with obvious cystic changes. The second case involved a 46-year-old female who presented with swelling of the right submandibular region. Panoramic radiography and lateral oblique mandible projection, which were used together with conventional sialography of the submandibular gland, revealed the so-called "ball in hand" appearance of the submandibular gland, and contrast-enhanced CT identified a lesion of 30 mm diameter with a well-defined annular margin and homogeneous low-density near the tumour centre. Benign pleomorphic adenoma was suspected, but histopathological examination identified schwannoma, predominantly comprising Antoni B type tissue.

Adult↗

Aging and oxidative stress in neurodegeneration.

The effect of oxidative stress on the function of brain synapse, the difference in susceptibility of synapse to hyperoxia with age, and the changes in vitamin E status by stress and aging were investigated. Synaptic membrane permeability to sucrose was increased with age. When rats were subjected to hyperoxia, the membrane permeability on each age increased significantly. The susceptibility of synapse of 25 month old rats exposed to stress was about 2.5 times higher than unexposed old rats. The synaptic plasma membrane fluidity decreased significantly either in response to hyperoxia or during aging. The thiobarbituric acid reactive substances (TBARS) in the synaptic plasma membranes increased with age, and those in the membranes of oxygen-exposed rats were higher than in the unexposed rats. The cholesterol/phospholipids (C/P) ratio of the membranes increased significantly with age, and the values in the membranes of oxygen-exposed rats increased more significantly than in unexposed rats of each age. In a measurement of fatty acid content in the membranes, the content of docosahexaenoic acid (DHA, C22:6) decreased significantly during aging and by hyperoxia. These results suggest that free radicals derived from oxygen may attack nerve terminals and peroxidize the membrane, resulting in the deterioration of function of brain synapse, and that susceptibility of synapse to oxidative stress was significantly increased with age. Vitamin E content in the synaptic plasma membranes decreased with age. When rats were subjected to oxidative stress, the content was lower in each age than in normal rat membranes. An intraperitoneal administration of vitamin E prior to stress reduced these abnormalities. It is obvious that vitamin E contributes to the protection against nerve terminal dysfunction caused by oxidative stress.

Aging↗

[Clinical studies on netilmicin].

Netilmicin (NTL), a new semisynthesized aminoglycoside, was evaluated in 11 episodes of infection in 10 patients, who had severe underlying diseases, such as acute myocardial infarction, cerebral infarction, malignancy and hepatic cirrhosis. The infection was bacteremia in 3 cases, urinary tract infections in 3 cases and respiratory tract infections in 5 cases. NTL was administered intramuscularly at a dose of 100 mg twice a day for 3 to 14 days. Overall clinical efficacy was only 40%, including excellent in 2 cases, good in 2 cases, fair in 3 cases and poor in 3 cases. Bacteriologically, 2 episodes of E. coli, 2 of S. marcescens and 1 of K. pneumoniae were eradicated, whereas, 2 of P. aeruginosa were decreased, and 1 of K. pneumoniae and 1 of P. rettgeri were persisted. Transient eosinophilia was observed in 1 case, and also nephrotoxicity was encountered in 1 case.

Aged↗