Presence of D-aspartate oxidase in rat liver and mouse tissues.

Rat liver D-aspartate oxidase activity, which had been reported to be undetectable, was found to be well detectable in dialyzed liver homogenate. The requirements of the enzyme for activity and its sensitivity to inhibitors were identical with the known properties of the enzyme from other sources. We also demonstrated for the first time the presence of the enzyme activity in mouse tissues and some other rat tissues using dialyzed tissue homogenates.

Characteristic difficulty in rhythmic movement with aging and its relation to Parkinson's disease.

A total of 137 healthy participants aged from 20 to 79 years, including 59 over 60 years, were examined using a finger-tapping test. The test requested the participant to respond synchronously with the right middle finger to a periodic sound train with frequencies of 1, 2, 3, 4, and 5 Hz (cycles/sec). Difficulty keeping the rhythmic movement at a given rate was found to be a characteristic of aging.

Identification of fibroblasts and Schwann cells in iris stroma by ruthenium red staining.

The fine structure of fibroblasts and Schwann cells in the iris stroma was studied by electron microscopy. The basement membrane of Schwann cells was well stained with ruthenium red, although it was discontinuous. In contrast, the iris fibroblasts were almost devoid of the basement membrane.

The relation of integrated EMG of the triceps brachii to force in rapid elbow extension.

The relationships between the integrated EMG (iEMG) of the first burst activity of the triceps brachii muscle and biomechanical variables such as acceleration, velocity and kinetic energy were examined for ballistic elbow extension in five healthy men. The duration of the first burst ceased within 100 msec in every subject. Although the regression analysis of each variable to iEMG was all significant, the correlation coefficient was the largest for mean or peak acceleration and the smallest for kinetic energy.

Timing and rate of development of tension produced by the fast voluntary contraction of the rectus femoris muscle.

Tension produced by isometric contraction of the rectus femoris muscle for rapid knee extension was examined at different levels of force with five normal subjects, using an on-line method to measure the timing and the rate of development of tension. Tension began to rise about 50 msec. after onset of electromyographic activity of the rectus femoris muscle, increased most sharply at about 60 msec.

Motor time of the rectus femoris under loading of different weights.

Motor time (MT) of the rectus femoris was measured for seven normal subjects during rapid extension of the knee joint at 60 degrees flexion in the sitting position with and without external loads on the leg. MT prolonged linearly with external load from 0 to 4 kg. Tangent of this linearity, the rate of tension development (RTD), was significantly different from one another of the subjects and was not related to MT without external load.

Two components of motor time: the tension lag and the tension-developing phase.

Motor time (MT) of the rectus femoris muscle for knee extension under loading on the leg with different weights and latency of isometric tension from the onset of electromyographic activities of the muscle were examined in 7 normal men. MT was linearly related to weights-loaded, indicating that the rate of rapid development of tension was almost linear even in its early phase. MT without a load obtained by calculation using the regression equation and the estimated weight of the leg and foot coincided with latency of isometric tension.

Uridine as an active component of sleep-promoting substance: its effects on nocturnal sleep in rats.

A 10-h intraventricular infusion of 10 pmol of uridine from 19.00 to 05.00 h resulted in significant increases in sleep in otherwise saline-infused male rats (n = 8) during the environmental dark period (20.

Premotor and motor reaction time as a function of force output.

The effects of variation in force output on fractionated reaction times (RTs) in elbow extension for 5 normal adults were examined. Force was manipulated by instructing the subject to respond with much or little force, and force output was measured by an accelerometer. Premotor RT increased with increased force output, indicating that organization of force for movement could affect not only the movement speed but the timing of its initiation.

Motor reaction time as a measure of rapid force generation of a muscle.

Motor reaction time (MT) of the vastus medialis, latency from the EMG onset to initiation of the actual movement of the lower leg, was examined for 19 normal subjects during rapid extension of the knee joint at various angles from 90 degrees to 0 degrees in the sitting posture. Muscular tension produced by maximal voluntary contraction (MVC) was measured at 80 degrees of the knee joint for 19 subjects. Also, EMG activities during period of MT were integrated at each angle of the knee for five subjects.

Finger tapping test as a means to differentiate olivo-ponto-cerebellar atrophy among spinocerebellar degenerations.

A finger tapping test in which the subject was requested to respond synchronously to the periodic sound signal was performed on 10 patients with OPCA, 10 other SCD and five suspected OPCA. The results indicated that the response of the patients with OPCA was specific among SCD. The response did not more synchronize to the signal above 2.

Disturbances of rhythm formation in patients with hemispheric lesion.

A total of 191 patients with hemispheric lesion mainly due to CVD were examined by the finger-tapping test, and their disturbances of rhythm formation, 'hastening phenomenon' (HP), were compared with those of Parkinson's disease. HP was observed in 56% of the right and 49% of the left hemiplegic patients. HP in the intact hand of the patient was highly correlated with that of the affected hand.