Strength of the trunk muscles is a key of motor control but it declines easily with the process of aging and/or disuse. In the present study we applied electrical stimulation (ES) to the abdominal muscles of the inactive elderly and investigated its local and general effects. We also intended to develop a new care preventive action for the inactive elderly. Eleven elderly people being admitted to an institute for nursing care participated to this study. Due to chronic disuse they could not walk independently during 3 months before start of ES despite intervention with common physical therapy. ES was performed twice a day during 2 months adding to physical therapy. Surface electrodes were put on the area of the bilateral abdominal oblique muscles. Before ES and 1month and 2 months after ES, we measured grip strength, maximum walking speed, time of getting up, flexibility of the trunk, standing balance, score of Functional Independence Measure (FIM) and cross sectional area of the abdominal muscles examined by Magnetic Resonance Imaging (MRI). After ES, walking speed, getting up time and the score of FIM improved significantly. Though MRI was examined in only one case remarkable increase of muscle volume was observed. As a result of ES, motor performance like walking and getting up improved. Furthermore, the level of ADL was elevated after ES because the score of FIM had been stable during 3 months before ES. The relationship between the change of abdominal soft tissue composition and the improvement of motor performance is unclear but the local change induced by ES may be one of triggers to improve general motor function.
Inspection by the MRI is also thought to be promising as well as the supersonic catheter and so on for the details inspection of the plaque inside the blood vessel wall. MR probe that can detect MR signal in just near the lesion site is necessary to observe it about 2 mm deep with high resolution. In this research, we have developed MR microprobes that have a shielded-loop type coil of which change in Q-value by the load is small. The shielded-loop was made by using strip line. It is flexible because it is made by stacking the thin films on which the wiring is formed. The coil part of this microprobe can be rolled into compact size and can be inserted into a catheter. Its coil expands outside of the catheter and can be used for imaging large area. We designed and made the microprobes and measured their fundamental electrical characteristics. Then, they were tested by using MR scanner and the resolution of MR images were evaluated. The thin microprobe that could be inserted into the 6 Fr (1 Fr = Ø0.33 mm) catheter was made and evaluated. Its Q-value was 22.7, and the resolution of MR image was 160 μm when sample was kiwi fruit.
Near-infrared differential absorbance spectra from pure water have been measured for phosphate buffer solutions (pH = 7.4) of human serum albumin (HSA) in the wavelength range of 750-2500nm. The peaks that follow HSA concentration can be observed in near-infrared differential absorbance spectra; in the 1650-1750nm and 2150-2350nm region. The near-infrared spectra in the 750-1350nm, 1550-1850nm and 2052-2500nm regions of the solutions have been subjected to partial least squares (PLS) regression analysis to make calibration models predicting the concentrations of the HSA. The calibration in the concentration range of 0-5g/dl has yielded a correlation coefficient of 0.999 and a standard error of prediction of 0.0283g/dl with latent variable of seven. This result suggests that the near-infrared differential spectra of HSA from pure water reference and its calibration model constructed by using PLS regression can pick up effectively the information about albumin contained in phosphate buffer solutions. This result can be a base of reagentless measurement of HSA in human serum and in vivo HSA measurement.
Motor racing drivers may be exposed to thermal stress, which can influence their performance and put them at risk of heat stroke. The aim of the work described here was to monitor core body temperature and other physiological and environmental variables continuously in racing kart drivers and to investigate the relationship between core body temperature and lap-time/lap-time-variability, the latter being an indication of driver performance. As an indication of core temperature we used the eardrum temperature, Teardrum, measured with a modified, extremely-compact radiation thermometer. We also measured instantaneous heart rate, the vector magnitude of acceleration, G, sweat weight, ambient temperature and relative humidity in the racing suit and full-face helmet, Ta(suit)/RHsuit/Ta(met)/RHmet, road temperature, and lap-time. The measuring instruments functioned satisfactorily during karting performed on a racing circuit. In all participants (n = 15:30.9 ± 6.4 S.D.yrs) during driving, we found that Teardrum gradually increased from 36.8°C to 38.2°C. It is suggested that the observed rise in Teardrum could be due to the G stresses to which the driver's were subjected, as heat production of the body was increased due to the increased muscle activity against G during driving. In addition, we found that the degradation of the local environment around the body (Ta(suit)/max = 41.0°C, RHsuit/max = 96.6%, Ta(met)/max = 41.0°C, RHmet/max = 93.5%) could be also be one of the major factors. We also found a statistically significant correlation between Teardrum and lap-time/lap-time-variability. These results suggest that monitoring of Teardrum could be of considerable importance in protecting racing driver's from heat stroke and assessing their performance during motor racing.
Neuronal cells in the human brain has minute and intricate structures in which a lot of water molecules diffuse restrictedly. In recent years, DWI has been focusd on as a method which can detect restricted diffusion of water molecules and visualize the structures containing water molecules. This approach is mainly used for diagnosis of pathology such as acute stroke. In addition, lately it has been suggested that this approach can be applied to fMRI with the fact that neuronal cells in the brain change their volumes during their activation. In the present study, with the Monte-Calro method we simulated the motions of water molecules in the restricted structures whose sizes were similar to those of neurons to find appropriate imaging parametrs for DW-fMRI. Simulation results demonstrated that imaging parameters and the size of restricted areas may change signal intensities. Furthermore, it was found that the difference of signal intensities due to the change in the size of restricted areas largely depends on the q-value which is one of imaging parameters. These results indicate that the present simulation can estimate the imaging parameters which emphasize the difference of signal intensities in DWI between before and after the sizes of cells change. In addition, we should choose appropriate q-value more carefully than b-value for the measurements of brain activations with DWI.