Rett syndrome (RTT) is a neurodevelopmetal disorder associated with mutations in the methyl-CpG-binding protein 2 (MeCP2) gene. MeCP2-deficient mice recapitulate the neurological degeneration observed in RTT patients. Recent studies indicated a role of not only neurons but also glial cells in neuronal dysfunction in RTT. We cultured astrocytes from MeCP2-null mouse brain and examined astroglial gene expression, growth rate, cytotoxic effects, and glutamate (Glu) clearance. Semi-quantitative RT-PCR analysis revealed that expression of astroglial marker genes, including GFAP and S100β, was significantly higher in MeCP2-null astrocytes than in control astrocytes. Loss of MeCP2 did not affect astroglial cell morphology, growth, or cytotoxic effects, but did alter Glu clearance in astrocytes. When high extracellular Glu was added to the astrocyte cultures and incubated, a time-dependent decrease of extracellular Glu concentration occurred due to Glu clearance by astrocytes. Although the shapes of the profiles of Glu concentration versus time for each strain of astrocytes were grossly similar, Glu concentration in the medium of MeCP2-null astrocytes were lower than those of control astrocytes at 12 and 18 h. In addition, MeCP2 deficiency impaired downregulation of excitatory amino acid transporter 1 and 2 (EAAT1/2) transcripts, but not induction of glutamine synthetase (GS) transcripts, upon high Glu exposure. In contrast, GS protein was significantly higher in MeCP2-null astrocytes than in control astrocytes. These findings suggest that MeCP2 affects astroglial genes expression in cultured astrocytes, and that abnormal Glu clearance in MeCP2-deficient astrocytes may influence the onset and progression of RTT.
We herein describe the first known case of pleuritis caused by Mycobacterium kyorinense without pulmonary involvement. A 48-year-old man undergoing immunosuppressant therapy presented with cough and dyspnea. An accumulation of pleural fluid was noted; however, computed tomography revealed no pulmonary lesions. Cultures of the fluid yielded non-tuberculous mycobacteria, which was identified as Mycobacterium kyorinense. The patient recovered after 6 months of therapy with clarithromycin and moxifloxacin. Clinicians should be aware that Mycobacterium kyorinense can cause pleuritis without pulmonary involvement. When mycobacterial species are isolated from the pleural fluid, precise identification and drug susceptibility testing are warranted.
Walking is the most important activity both for elderly people and rehabilitants to spend their daily life safely, comfortably and independently. Walking is the most fundamental movement and athletic ability. For the elderly people, walking especially contributes to improving and maintaining the muscle power, the respiratory and circulatory organ systems, and further walking is a valuable activity to prevent a bedridden condition. This paper proposes a walking assist machine for the elderly people, which use a new active-ankle-foot support machine. Its machine matched to the movement of foot joint. The prototype was developed, and the performance was evaluated.
With the percentage of elderly people increasing every year, we proposed a walking assistance apparatus for disabled and elderly person, which is used for gait training and rehabilitation. We used zero-moment point (ZMP) control method to ensure stability of the walking assistance apparatus. Since users need to walk on stairs and the distance of every two stairs is invariable, the stride length of the apparatus is supposed to be constant. We compensated ZMP of the apparatus by adjusting the posture and the position of center of gravity (CoG). Thereby, the projection of gravity and inertia force can be maintained in the support polygon. From simulations and experiments, we can adjust the posture of the apparatus and user when instability occurs to prevent the user from stumbling. This method is suitable for walking on flat ground and stairs.
Proper exercise is suggested to the elderly for the prevention of a stroke. However, when the elderly do exercise, they are easy to feel mental and physical fatigue, such as weak emotion and muscle fatigue. These reasons make them the reduction of willingness for exercise and further cause a stroke. Thus, it is necessary to study the emotion and body condition of the elderly. The goal of this study is to make the elderly who can have positive emotion and better body condition for maintaining motivation during exercise. A new method considering emotion and muscle fatigue evaluation combined with a walking assistive device was proposed. We respectively studied the emotion-walking relationship, emotion promotion method, and muscle fatigue evaluation. In our previous studies, the emotion-walking relationship was confirmed. The emotion promotion method is proposed using walking strategies in this study. The findings exhibited that the emotion could be promoted to the positive area of the 2D emotion map. Furthermore, a new muscle fatigue evaluation method based on near-infrared spectroscopy (NIRS) is proposed. The findings indicated that the muscle fatigue condition is observed by the difference between the concentration of oxygenated hemoglobin and the concentration of deoxygenated hemoglobin. After that, combining emotion recognition and muscle fatigue evaluation, the new three-dimension (3D) emotion-fatigue model was created to display the mental and physical conditions. Finally, this proposal can be used for various applications for the promotion of exercise and rehabilitation.
Background:There are few reports on the current awareness and status of venous ultrasonography, including the number of specialists who perform this procedure, in a specific regional area in Japan.
Due to the growing elderly population in many developed countries like Japan, assistive devices are increasingly needed to overcome the difficulties of their activities of daily living (ADL). The motion of standing up places a particular burden on the ankle and knee joints and connects static motions (e.g., sitting and lying) and kinetic motions (e.g., walking and climbing up/down the stairs). In our previous research, two types of standing-up assistance apparatuses were introduced according to the suitable standing-up motions. However, these devices are bulky and cannot be widely used in practical settings such as bus terminals. Regarding the suitable standing-up motions of the elderly in the previous literature, a standing-up apparatus with a pantograph mechanism is introduced to diminish the size of the mechanism based on three design principles: (1) the trajectory of the user's COG is an arc; (2) the trajectory of the user's hip joint while standing up is a straight line at an angle of 45 [deg] from the horizon; and (3) the user is supported until the knee angle reaches 60 [deg]. Simulations showed that the load on knee and ankle joint is decreased, and user may stand up easily with our proposed apparatus. A prototype of the apparatus that may be installed on various chairs in public was fabricated. Considering that the apparatus may be used in places without electric power supply, the apparatus is made simply with links and a gas spring instead of electric actuators. Experimental measurements of the trajectories of the center of gravity (COG) and hip joints show that the proposed apparatus may help users to stand in a way that minimizes stress on their lower-body joints.
To enable the user move freely and stably without operating any control interfaces, we developed a motion prediction system based on logistic regression method for Kinect-based upper-limb assistive device. A probabilistic output is provided by classifying spatial vectors and performing the pre-trajectory with the highest probability, 85% of classification accuracy can be achieved.
To provide better guidance for patients or the elderly during the self-rehabilitation, a haptic system based on the asymmetric vibration was proposed. Due to the Non-linearity of Perception asymmetric vibration periodic movement can provide a sense of pushing and pulling. In order to better support human motion, we evaluated the sensitivity of different parts of the human body to this haptic assist. And by combining with the gyro-sensor through the contrast experiment, we compared the accuracy of motion learning with or without the haptic assist. The results of three subjects showed that the accuracy of motion learning was improved compared to without haptic assist. Therefore, the system has great potential in the guidance of patients' self-rehabilitation.
