Biomedical subjects
Publications and source records attributed to M Akai.
We describe a patient with fibroma of the vulva. The tumor had areas of marked hypointensity consistent with fibrosis on T1 and T2 weighted magnetic resonance (MR) images. The presence of abundant fibrous tissues on MR images enabled us to make a preoperative diagnosis of fibroma.
This study was conducted to determine the effect of footwear modification on patients with neuromusculoskeletal disorders. Two analyses, the center of pressure and the in-shoe plantar pressures, were studied with the help of healthy volunteers so that the effect of shoe modifications could be assessed. The ground force under the sole of the shoe was measured while the subjects were walking, and the plantar pressure at the foot-insole interface and its distribution were measured while the subjects were in both the standing and walking positions, wearing the trial shoes. The trial shoes had three different types of heels-standard heel, Thomas heel, and reverse Thomas heel-and had three different locations for the rocker bar--just under the metatarsophalangeal joint, 1 cm behind the metatarsophalangeal joint, and 1 cm before the metatarsophalangeal joint. The shift change at the center of pressure showed that the Thomas heel generally pushed the center of pressure more laterally and the reverse Thomas heel shifted it medially more than the standard heel did. While the subjects were in a stable standing position wearing the Thomas heel shoes, the medial forefoot and the lateral heel region's pressure showed significant reduction in the plantar pressure and the lateral forefoot and the medial heel showed a tendency to rise, compared with the standard heel condition. When the trial shoes' heels were changed to the reverse Thomas heel, the above changes tended to reverse. Tests at the foot-insole interface showed that the different types of heels and the location of the bar could change not only the pressure distribution but also the duration of the plantar pressure under the lateral area that shifted to the medial area when the subjects walked. This pressure measurement method was very useful for the design and evaluation of such footwear.
To investigate the influence of daily activity on changes in the physical fitness of people with post-stroke (cerebrovascular disorders) hemiplegia, we evaluated the follow-up exercise load test of 30 ambulatory male patients with post-stroke hemiplegia. Between the times of the two tests, patients had no special supervised training. They were advised by their physicians to exercise according to the result of an exercise-loading test. We determined peak oxygen uptake and O2 consumption at the ventilatory threshold point. After 9.4 months, the mean peak oxygen uptake improved significantly from 17.7 to 21.1 ml/min/kg, and ventilatory threshold point also improved significantly from 11.4 to 13.6 ml/min/kg. Among the nine subjects who returned to their jobs, subjects who previously went to their offices by public transportation showed more improvement in ventilatory threshold point level than did subjects who previously walked to their offices. Among the 21 subjects who did not return to work, those who exercised regularly (primarily by walking) showed more improvement of peak oxygen uptake level than did subjects who did not exercise regularly. In conclusion, people with hemiplegia who are living in the community can improve their physical fitness without formal supervised training by simply increasing their daily activities.
A case of soft tissue tumor in the left brachialis muscle of a 49-year-old Japanese female patient was studied by electron microscopy. The tumor was diagnosed as intramuscular myxoma by light microscopy, but electron microscopic observation revealed that the tumor almost entirely consisted of cells similar to normal perineurial cells. The tumor cells possessed long, slender cytoplasmic processes covered by well-developed but discontinuous basal laminae, clusters of pinocytotic vesicles, and infrequent intercellular junctions. Perineurial cells have also been observed in other peripheral nerve lesions: neurofibromas, nerve sheath myxomas, and localized hypertrophic neuropathies. However, the term "perineurioma" or "perineurial cell tumor" should be reserved for discrete tumorous masses that are almost entirely composed of perineurial cells without evidence of residual axons, Schwann cells, fibroblasts, or tactile corpusclelike structures. Perineurioma may represent a third category of peripheral nerve sheath tumors, ultrastructurally distinct from schwannomas and neurofibromas.
The effect of thoracic irradiation on antibiotic penetration into the alveolar space was determined in a hemithoracic irradiation rat model to evaluate radiation-induced acute alveolar injury at various time intervals. The results of this investigation may be summarized as follows: (1) The transfer of ceftazidime (CAZ: Modacin) from blood to lung tissue, that is, the permeability of pulmonary capillary epithelium, and the transfer of ceftazidime from lung tissue to bronchoalveolar lavage fluid, that is, the permeability of the alveolar epithelium, peaked at 4 to 5 weeks after thoracic irradiation; (2) the time course of change in the absolute concentration of ceftazidime in lung tissue showed a significant increase not only in the irradiated lung but also in the contralateral non-irradiated lung 3 days or more after irradiation. The finding that the administration of antibiotics may cause a significant increase in drug concentration in lung tissue even in the contralateral lung at 3 days after irradiation suggests that the change induced at the alveolar level immediately after irradiation affects the non-irradiated lung field through an as yet unknown mechanism.