Publications by authors named "Tasuku Miyoshi"

Swimming motions of rays that swim using undulation locomotion are not always symmetrical; there may be a phase difference between the left and right pectoral fins. However, few studies on the swimming of rays have mentioned left and right pectoral fin movements. Moreover, the effects of movements of the left and right pectoral fins on swimming have not been clarified.

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The purpose of this study was to develop a six-degree-of-freedom parallel mechanism moving platform to investigate the effects of multimodal sensory feedback information while standing upright. We constructed a custom-designed disturbance-applying instrument (DAI) consisting of a support surface suspended from eight pneumatic artificial muscles. The posture of the support surface was controlled with a proportional-integral-derivative (PID) feedback system using an infra-red camera-based real-time 3D motion capture system, and was estimated by step and frequency responses.

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Undulatory underwater swimming (UUS) is an important swimming technique after a start and after turns. It was considered that a higher swimming velocity (U) resulted from a higher kick frequency (f), and greater propelling efficiency, i.e.

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Purpose: To develop an aquatic exercise device to facilitate locomotive motor output and achieve repetitive physiological gait patterns to improve movement dysfunctions.

Methods: A custom designed leg movement apparatus (LMA) consisted of closed 4-linkage mechanisms and one-length changeable link using a spring. Three-dimensional motions and electromyographic (EMG) activities were recorded in eight healthy subjects to evaluate the reproducibility of the physiological gait patterns using the LMA with or without a spring apparatus in water.

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Quiet standing posture in humans has often been modeled as a single inverted pendulum pivoting around the ankle joint. However, recent studies have suggested that anti-phase action between leg and trunk segments plays a significant role in stabilizing posture by reducing the acceleration of the center of mass (COM) of the body. The aim of this study is to test the hypothesis that anti-phase action is attenuated in the elderly compared to the young.

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Article Synopsis
  • This study focuses on creating a body weight support gait training system designed for patients with stroke and spinal cord injuries, utilizing a powered orthosis and body weight support equipment.
  • The powered orthosis uses pneumatic McKibben actuators, mimicking human muscle movements, and can be customized for different body sizes.
  • The system includes features to support body weight and limit movement to the sagittal plane, with experiments conducted to evaluate its mechanics and effectiveness in aiding gait training.
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The purpose of this study is to develop a body weight support gait training system for stroke and spinal cord injury. This system consists of a powered orthosis, treadmill and equipment of body weight support. Attachment of the powered orthosis is able to fit subject who has difference of body size.

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Purpose: Muscular co-contraction resulted in corrected elbow and shoulder joint stiffness; however, this correction neither ameliorated endpoint oscillation nor assisted in the execution of smooth two-joint arm movements. We hypothesised that the reacquisition of smooth arm movements became synonymous with the restoration of time-domain reciprocal electromyographic (EMG) activities in biarticular arm muscles. The purpose of this study was to investigate whether or not the restored reciprocal EMG activities in biarticular arm muscles reflected improved smooth motor performance in patients with stroke after 10 days of two-joint arm-movement training.

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The objective of this study was to develop a method of muscle structure measurement based on the automatic analysis of muscle fibers, proximal fascias, and distal aponeurosis movements as revealed by a time-series of ultrasound images. This method was designed to detect changes in the length of muscle fiber movements, and its validity was demonstrated in a time-series of muscle movement, slow ankle dorsiflexion (10 degrees/s), by comparison to manual measurement. The results showed that, when this method was used, the changes in the length of the muscle fiber under slow muscle movement were smaller than those in manual operations by novice individuals.

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Purpose: To develop a robotic gait trainer that can be used in water (RGTW) and achieve repetitive physiological gait patterns to improve the movement dysfunctions.

Method: The RGTW is a hip-knee-ankle-foot orthosis with pneumatic actuators; the control software was developed on the basis of the angular motions of the hip and knee joint of a healthy subject as he walked in water. Three-dimensional motions and electromyographic (EMG) activities were recorded in nine healthy subjects to evaluate the efficacy of using the RGTW while walking on a treadmill in water.

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To investigate the effects of gravity-related somatosensory information on spinal human reflexes, the soleus H-reflex was recorded in ten healthy subjects walking on a treadmill at 2.0 km/h on land and in water. The modulation pattern of the soleus H-reflex was determined in ten different phases of the step cycle.

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We investigated relative activations in the synergistic ankle plantarflexor muscles, the soleus (SOL) and medial gastrocnemius (MG), while subjects were walking in water. Ten healthy volunteers walked in water under three different load- and four different speed-conditions. The depth of water was to the axilla of each subject, which reduced about 80% of his or her body weight.

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Objective: To clarify the functional roles of lower-limb joint moments and their contribution to support and propulsion tasks while walking in water compared with that on land.

Design: Sixteen healthy, young subjects walked on land and in water at several different speeds with and without additional loads.

Background: Walking in water is a major rehabilitation therapy for patients with orthopedic disorders.

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We report a 73-year-old woman with meningitis-type neurosyphilis presenting the main symptom of the left total ophthalmoplegia. Three months after the appearance of the deviation of the eyeball to the inside and ptosis of the left eyelid, the left eyelid was completely closed. On admission, about four months after the appearance of neurosyphilis, she showed paralysis of the left oculomotor nerve, trochlearis nerve and abducens nerve, and the right mydriasis and absent light reflex.

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Purpose: The purpose of this study was to compare the changes in ground reaction forces (GRF), joint angular displacements (JAD), joint moments (JM) and electromyographic (EMG) activities that occur during walking at various speeds in water and on land.

Method: Fifteen healthy adults participated in this study. In the water experiments, the water depth was adjusted so that body weight was reduced by 80%.

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Objective: To investigate the effects of loading and unloading of the lower limb joints on the soleus H-reflex in standing humans.

Methods: H-reflexes were elicited in the soleus muscle in subjects standing on a force platform in a water tank under the following loading conditions of the ankle and knee joints: control condition; reduced loads of -10 and -20 N; imposed loads of 10 and 20 N. The joint loading was altered by changing the combinations of buoys and weights attached to the lower limb segments, while total body weight was kept constant.

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The purpose of this study was to investigate how gravity level affects the excitability of the soleus muscle (SOL) motoneuron pool to la afferent input while erect posture is maintained in humans. Three healthy male subjects participated in an experiment whereby three different gravity conditions (micro gravity (MG), normal gravity (NG), and hyper gravity) were imposed using a parabolic flight procedure. The SOL H-reflex was evoked every 2 seconds while the subjects kept an erect posture.

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The purpose of this study was to investigate that considers the influence of the moderate exercise has on the upper limbs and the legs during 21 days head down bed rest. Therefore motor evoked potential (MEP) induced by transcranial magnetic stimulation (TMS) in lower leg muscles of four healthy subjects were investigated before/after and during bed rest. There were no significant differences statistically between soleus MEPs before and after bed rest in all subjects.

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Purpose: Walking in water is a widely used rehabilitation method for patients with orthopedic disorders or arthritis, based on the belief that the reduction of weight in water makes it a safer medium and prevents secondary injuries of the lower-limb joints. To our knowledge, however, no experimental data on lower-limb joint moment during walking in water is available. The aim of this study was to quantify the joint moments of the ankle, knee, and hip during walking in water in comparison with those on land.

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A 66-year-old man developed paresthesia of the distal parts of the bilateral lower limbs a week after his upper respiratory infection, followed by the weakness with the legs and paresthesia with the lip area, tongue and finger tips. Those symptoms gradually became worse to the point that he was unable to walk 10 days later. Although skin pigmentation, edema, and lymph node swelling were not found, we made a diagnosis of Crow-Fukase syndrome (CFS) because of clinical features of polyneuropathy, IgG-lambda type M proteinemia, endocrinological abnormality, elevated plasma level of vascular endothelial growth factor (VEGF) and extramedullary plasmacytoma in his abdomen.

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Many studies have demonstrated that the firing behavior of single motor units varies in a nonlinear manner to the exerted torque during gradual muscle contraction and relaxation. However, it is unclear whether corticospinal excitability has such a hysteresis-like feature. In this study, we examined corticospinal excitability using transcranial magnetic stimulation (TMS) during gradual muscle contraction and relaxation for torque regulation in elbow flexor muscles.

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The purpose of the present study was to ascertain the contribution of peripheral sensory inputs to posture-related Hoffman reflex (H-reflex) modulation in the human soleus muscle. The soleus H-reflexes were elicited in the sitting (SI) and passive standing (ST) conditions in patients with clinically complete spinal cord injuries (SCI) and in neurologically normal subjects. The results clearly showed suppression of the H-reflex amplitude during the ST compared with the SI condition especially in the SCI group.

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The purpose of this study was to investigate how gravity level affects the excitability of the soleus muscle (SOL) motoneuron pool to Ia afferent input while erect posture is maintained in humans. Three healthy male subjects participated in an experiment whereby three different gravity conditions [microgravity (MG), normal gravity (NG), and hypergravity (HG)] were imposed using a parabolic flight procedure. The SOL H-reflex was evoked every 2 s while the subjects kept an erect posture.

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