Here we evaluate the influence of a substrate structures on cell migration in culture. Two types of a substrate were compared: a fibrous and a Skin-Substrate prepared using a spray method. Both types of substrates were made of polyurethane. As a control, cell behavior was also evaluated in a polystyrene dish. The mouse fibroblast cell line NIH-3T3 was used for the experiment. All three types of dish were observed by microscopy at 48-hour intervals over a period of 144hours. The extent of cell migrating was defined as the radius of the area to which the cells attached. These distances were measured from micrographs and the data shown as means±SD. We found that migration distance in the culture with the Fibrous-Substrate was 3571±334.μm compared to 1848±239 μm for the Skin-Substrate and 1490±71μm in the control. We conclude that the micro-sized structure of the Fibrous-Substrate encouraged both rapid and extensive cell migration.

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We were able to develop the anti-thrombogenic surface coating technology “T-NCVC coating” which allows for the continuation of long-term anticoagulation effects. In this study, we focused on the dynamics of blood protein adsorption to the coated surface as well as cell adhesion using cultured fibroblasts and analyzed the antithrombotic mechanisms of T-NCVC coating. As the characteristics of our coating technology with regard to blood, our study showed the inhibitory actions against cell adhesion not affected by proteins adhering and the presence of other plasma proteins on the coated surface. On the other hand, our technology was identified that it has membrane-toxicity against blood cells indicated by the increase in neutrophil activation and hemolytic rate. These actions between the blood and our coating technology were suggested to be one of the causes for the long-term effects of this coating technology. These antithrombotic mechanisms were different from those that had been previously proposed and are important observations in clarifying the process of thrombosis formation on artificial materials coming in contact with blood.

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Cardiac mechanical and electrical activities are interrelated closely. The interrelationships between these are constructed with Mechano-Electric Feedback(MEF), however less is known about cellular mechanisms of it. Recent progress on ventricular assist device therapy for myocardial recovery has been indicated the possibilities to improve the failed heart function normally. As one of the mechanisms to suppress or reverses the remodeling of cardiac myocyte following to heart failure, mechanical unloading has been assumed to be a necessary factor for cardiac function recovery. However, less is known for this mechanism and strategies for effective therapy. To speculate the mechanism of myocardial recovery following to mechanical unloading, the effects of differential contraction manner including isotonic and isometric contraction for action potentials(APs)were evaluated with numerical analysis. The excitation-contraction coupling was modeled with the combination of action potential model(LRd model)and contractile force generation model(NL model). The other pathway for construction of MEF was realized by an incorporation of stretch-activated channels. The differences of action potential duration between isometric or isotonic contraction are very limited on normalion concentration condition, however, the crossover of AP was observed on calcium-overloaded condition. Moreover, arrhythmogenic responses are indicated on isotonic contraction with calcium-overloaded condition.

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A wearable electronic travel aid to guide visually impaired has been developed. Visually impaired are at risk of a lot of accidents on a solo walking. Therefore, it is necessary to support safety walking with the electronic travel aids. The detection of the obstacles is one important factor for the safety. In this paper, the method of detection of the obstacles is proposed. Descending down steps like the platform and down stairs are very dangerous places. Therefore, the obstacles to detect are walls, upstairs, descending down steps and downstairs. An IR range finder and the fuzzy reasoning are used to detect these objects. The production rules used for the fuzzy reasoning are made based on using human being's sense. The experimental results show that the obstacles could be detected and distinguish a type by the coverage of 100% at 750mm in front of the obstacles. The results showed this device is effective as the detection device of the obstacle to support the visually impaired. The researched and developed device was practicable and suitable for the life environment.

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We have developed an instrumental system of wheelchair to analyze human movements while driving wheelchair. So as to measure the driving force and wheel movement, a rotary encoder and a six degree-of-freedom force/moment sensor are equipped at the axle of main wheel. We bind another two position/orientation sensors on upper arm and forearm of the subject. The measurement values for a subject are converted as time series to the joint angles of upper limb, which are used to evaluate the wheelchair propulsion with the driving forces. By using the developed instrumental system, we can obtain the necessary information of three dimensional position/orientation and force/moment which describe the wheelchair propulsion perfectly in the mechanical terms.

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The purpose of this study is to evaluate the physical effects of santalol inhalation on sleep. Salivary amylase activity(sAMY)was used as an index of sympathetic nervous activity. At the same time, results of a subjective evaluation of sleep and sleep duration were used as the indexes of sleep quality. Eighteen Japanese female adults suffering from insomnia were enrolled. The subjects applied 0.5g of santalol cream on their skins each bedtime for 2 weeks. Without cream application was carried out as the control. In the study without cream, the sAMY increased by 37.7% during the day and by 47.5% at night, compared with that in the morning. In the study with cream, the sAMY increased by 35.6% during the day and by 10.0% at night, compared with that in the morning. The diurnal variation of sAMY with the use of santalol cream showed similar to the circadian rhythm of sympathetic nervous activity for normal people. In the subjective evaluation of sleep and sleep duration, there were no significant differences between two studies. However, the subjects who preferred the santalol fragrance slept longer with the use of cream.

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