[Unilateral Posterior Reversible Encephalopathy Syndrome after Ventriculo-Peritoneal Shunt for Normal Pressure Hydrocephalus Following Subarachnoid Hemorrhage: A Case Report].

The patient, a 79-year-old man, experienced a Hunt & Kosnik grade IV subarachnoid hemorrhage, presenting with sudden-onset coma and severe left hemiplegia. We performed cranial clipping surgery for a ruptured aneurysm on the right middle cerebral artery the same day. Post-operative recovery proceeded smoothly, with gradual improvements in disturbed consciousness and left hemiplegia. Three weeks post-operation, CT revealed low-density areas in the right frontal and temporal lobe, believed to be due to subarachnoid hemorrhage, as well as hydrocephaly. We then performed a lumbo-peritoneal (L-P) shunt for the hydrocephaly. Two months later, the patient experienced shunt occlusion, and we performed a ventriculo-peritoneal (V-P) shunt revision (pressure: 6 cm H(2)O). Headaches, severe decline in cognitive function, and worsened left hemiplegia were observed seven weeks post-shunt revision. Cranial CT revealed widespread low-density areas in right posterior cerebral white matter. We suspected unilateral posterior reversible encephalopathy syndrome (PRES) after performing cranial MRI and cerebral angiography. Increasing the set pressure of the shunt improved the symptoms and radiographic findings. PRES is typically bilateral, and unilateral incidents are rare. This is the first report of unilateral PRES secondary to shunt operation. Its unilaterality appears to have been caused by unilateral brain damage or adhesions to the brain surface from the subarachnoid cerebral hemorrhage. Overdrainage post-shunt can also induce PRES. Diagnosis of PRES is more difficult in unilateral cases;practitioners must keep PRES in mind as a rare complication post-shunt operation.

[CNS primitive neuroectodermal tumor suspected as a secondary recurrence after radiation therapy for medulloblastoma:a case report].

We report a case of a suspected secondary central nervous system(CNS)primitive neuroectodermal tumor(PNET)that developed 25 years after radiation therapy for a medulloblastoma of the cerebellum. At 5 years of age, the patient underwent craniotomy and subsequent radiation therapy of the whole brain(39Gy), whole spinal cord(9Gy), and posterior fossa(49Gy)for the treatment of a medulloblastoma of the cerebellum;the patient did not receive chemotherapy. After radiation therapy, the medulloblastoma completely receded and did not recur. Twenty-five years later, at 30 years of age, the patient visited our institution experiencing right-sided hemiparesis and aphasia that had arisen approximately 1 month prior and had gradually worsened. The patient was subsequently hospitalized after experiencing disturbed consciousness and a generalized convulsion seizure. Gadolinium-enhanced magnetic resonance imaging(MRI)revealed a mass accompanied by a large cyst in the left frontal lobe. Complete tumor resection was achieved via macroscopic surgery, and the histopathological findings were indicative of CNS PNET. Considering the tumor occurred in the same site where radiation therapy had been previously administered to treat a medulloblastoma, additional radiotherapy was avoided in favor of combination chemotherapy with ifosfamide, cisplatin, and etoposide. Tumor recurrence was not observed in a follow-up MRI after 6 courses of ICE therapy, and the patient has resumed a normal life. The present case, a CNS PNET, is suspected as a secondary brain tumor induced by radiation therapy previously used to treat a medulloblastoma, and it represents a rare late-onset complication of radiation therapy. For the treatment of PNET, we believe that maximal safe surgical resection of the tumor and post-operative radiation therapy are typically necessary for long-term survival. However, taking into account the risks of repeated exposure to radiation, we did not perform post-operative radiation therapy for this patient. We have not observed recurrence to date;however, the patient will require a strict follow-up schedule hereafter.

The dipeptide Phe-Phe amide attenuates signs of hyperalgesia, allodynia and nociception in diabetic mice using a mechanism involving the sigma receptor system.

BACKGROUND: Previous studies have demonstrated that intrathecal administration of the substance P amino-terminal metabolite substance P1-7 (SP1-7) and its C-terminal amidated congener induced antihyperalgesic effects in diabetic mice. In this study, we studied a small synthetic dipeptide related to SP1-7 and endomorphin-2, i.e. Phe-Phe amide, using the tail-flick test and von Frey filament test in diabetic and non-diabetic mice. RESULTS: Intrathecal treatment with the dipeptide increased the tail-flick latency in both diabetic and non-diabetic mice. This effect of Phe-Phe amide was significantly greater in diabetic mice than non-diabetic mice. The Phe-Phe amide-induced antinociceptive effect in both diabetic and non-diabetic mice was reversed by the σ1 receptor agonist (+)-pentazocine. Moreover, Phe-Phe amide attenuated mechanical allodynia in diabetic mice, which was reversible by (+)-pentazocine. The expression of spinal σ1 receptor mRNA and protein did not differ between diabetic mice and non-diabetic mice. On the other hand, the expression of phosphorylated extracellular signal-regulated protein kinase 1 (ERK1) and ERK2 proteins was enhanced in diabetic mice. (+)-Pentazocine caused phosphorylation of ERK1 and ERK2 proteins in non-diabetic mice, but not in diabetic mice. CONCLUSIONS: These results suggest that the spinal σ1 receptor system might contribute to diabetic mechanical allodynia and thermal hyperalgesia, which could be potently attenuated by Phe-Phe amide.

Athermal strength of pure aluminum is significantly decreased by severe plastic deformation and it is markedly augmented by subsequent annealing.

Over the last two decades, it has been considered that fine crystal grains produced by severe plastic deformation (SPD) lead to an extraordinarily high metal strength. The present study reveals that this understanding is basically incorrect. In our uniaxial tensile tests on industrial pure aluminum at an ultralow strain rate of [Formula: see text], we observed that SPD accompanied by grain refining significantly softened the material. The fundamental strength effective for real structures and structural materials should mean an eternal capability to bear stresses caused by external forces, which is independent of time, that is, athermal. We tried to extract quantitatively the athermal (time-independent) strength from the total strength measured in uniaxial tensile tests under the assumption that the total stress can be additively divided into athermal and thermal (time-dependent) components. As a result of systematic experimental investigation, we found that the athermal strength is significantly reduced by SPD and then markedly increased by subsequent low-temperature annealing. In addition, we confirmed that SPD promotes an increase in the time dependence (viscosity) of the material and that subsequent annealing removes most of the viscosity caused by SPD. The material processed by SPD acquires its prominent time-independent strength after low-temperature annealing.

Motion discrimination technique by EMG signals using hyper-sphere model.

This study developed a method of discriminating real-time motion from electromyogram (EMG) signals. We previously proposed a real-time motion discrimination method using hyper-sphere models that discriminated five motions (open, grasp, pinching, wrist extension, and wrist flexion) above 90% and quickly learned EMG signals. Our method prevents elbow motions from interfering with hand motion discrimination. However, we presume in our method that feature quantities do not change with time. Discrimination accuracy might deteriorate over time. Additionally, our method only discriminated three motions (open, grasp, pinching) for finger motions. This paper proposes the effectiveness of our method for changing feature quantities caused by time variation and a real-time motion discrimination method using new hyper-sphere models for four finger motions (open, grasp, pinching, and 2-5th finger flexion). We carried out two experiments and verified the effectiveness of our method for changing feature quantities and four finger motions discrimination using the new hyper-sphere models.

Quantitative evaluation of unrestrained human gait on change in walking velocity.

In human gait motion analysis, which is one useful method for efficient physical rehabilitation to define various quantitative evaluation indices, ground reaction force, joint angle and joint loads are measured during gait. To obtain these data as unrestrained gait measurement, a novel gait motion analysis system using mobile force plates and attitude sensors has been developed. On the other hand, a human maintains a high correlation among the motion of all joints during gait. The analysis of the correlation in the recorded joint motion extracts a few simultaneously activating segmental coordination patterns, and the structure of the intersegmental coordination is attracting attention to an expected relationship with a control strategy. However, when the evaluation method using singular value decomposition has been applied to joint angles of the lower limb as representative kinematic parameters, joint moments related to the rotational motion of the joints have not yet been considered. In this paper, joint moments as kinetic parameters applied on the lower limb during gait of a normal subject and a trans-femoral amputee are analyzed under change in walking velocity by the wearable gait motion analysis system, and the effectiveness for quantitatively evaluate the rotational motion pattern in the joints of the lower limb by using joint moments is validated.

Calculation of joint reaction force and joint moments using by wearable walking analysis system.

In gait analysis, which is one useful method for efficient physical rehabilitation, the ground reaction force, the center of pressure, and the body orientation data are measured during walking. In the past, these data were measured by a 3D motion analysis system consisting of high-speed cameras and force plates, which must be installed in the floor. However, a conventional 3D motion analysis system can measure the ground reaction force and the center of pressure just on force plates during a few steps. In addition, the subjects' stride lengths are limited because they have to walk on the center of the force plate. These problems can be resolved by converting conventional devices into wearable devices. We used a measuring device consisting of portable force plates and motion sensors. We developed a walking analysis system that calculates the ground reaction force, the center of pressure, and the body orientations and measured a walking subject to estimate this system. We simultaneously used a conventional 3D motion analysis system to compare with our development system and showed its validity for measurements of ground reaction force and the center of pressure. Moreover we calculated joint reactions and joint moment of each joint.

Gait motion analysis in the unrestrained condition of trans-femoral amputee with a prosthetic limb.

Trans-femoral amputees must regain moving pattern by refined rehabilitation program using ground reaction forces, joint angles and joint moments applied on a prosthetic limb. On the other hand, understanding those loads and kinematic variables is indispensable for gait analysis based on the biomechanical consideration of trans-femoral amputees. However, conventional prosthetic gait training systems cannot measure long continuous walking motions. In this paper, ground reaction forces and kinematic parameters applied on trans-femoral prosthesis are measured by the prosthetic gait motion analysis system using mobile force plate and attitude sensor for the unrestrained gait measurement. As a result of the experiments, the patterns of antero-posterior axis ground reaction forces and joint moments about the medio-lateral axis are remarkably different among the five activities. Finally, the effectiveness of the developed prosthetic gait training system to consider biomechanics and kinematics in trans-femoral prosthesis is validated.

Forearm motion discrimination technique using real-time EMG signals.

The objective of this study is to develop a method of discriminating real-time motion from electromyogram (EMG) signals. We previously proposed a motion discrimination method. This method could discriminate five motions (hand opening, hand closing, hand chucking, wrist extension, and wrist flexion) at a rate of above 90 percent from four channel EMG signals in the forearm. The method prevents elbow motions from interfering with hand motion discrimination. However, discrimination processing time of this method is more than 300 ms, and the shortest delay time that is perceivable by the user is generally regarded to be roughly 300 ms. Furthermore, a robot hand has a mechanical delay time. Thus, the discrimination time should be less than 300 ms. Here, we propose a real-time motion discrimination method using a hyper-sphere model. In comparison with the old model, the hyper-sphere models can make more complex decision regions which can discriminate at the state of the motion. Furthermore, this model can learn EMG signals in real-time. We experimentally verified that the discrimination accuracies of this method were above 90 percent. Moreover, elbow motions did not interfere with the hand motion discrimination. The discrimination processing time was less than 300 ms, and was about 30 percent shorter than that of the old method.

Biomechanical consideration based on the unrestrained gait measurement of trans-femoral amputee with a prosthetic limb.

Trans-femoral amputees must regain moving pattern by refined rehabilitation program using loads applied on a prosthetic limb. On the other hand, understanding those loads is indispensable for biomechanical consideration of trans-femoral amputees. However, conventional prosthetic gait training systems cannot measure long continuous walking motions. In this paper, loads applied on trans-femoral prosthesis are measured by the prosthetic gait training system for the unrestrained gait measurement. As a result of the experiments, the patterns of moments about the medio-lateral axis are remarkably different among the six activities. Finally, the effectiveness of the developed prosthetic gait training system to analyze biomechanics in trans-femoral prosthesis is validated.

Development of a novel six-axis force/moment sensor attached to a prosthetic limb for the unrestrained gait measurement.

Since the number of trans-femoral amputees has increased by industrial or traffic accidents in modern society, a prosthetic limb has been required. In this case, those amputees must regain moving pattern by efficient gait training using load conditions on a prosthetic limb as quantitative evaluation indices. However, conventional gait training systems cannot measure long continuous walking motions. In this paper, a novel six-axis force/moment sensor, which is attached to a prosthetic limb for the unrestrained gait measurement, is developed. As a result of applying response surface method and desirability function, optimum design variables to reduce interference components are obtained. Finally, characteristics test by applying optimum design variables is performed and the effectiveness of the developed sensor is validated.

The effect of substance P1-7 amide on nociceptive threshold in diabetic mice.

We previously demonstrated that intrathecal treatment with substance P metabolite substance P(1-7) induced anti-hyperalgesia in diabetic mice. In the present study, we have used a synthetic analog of this peptide, the substance P(1-7) amide, showing higher binding affinity than the native heptapeptide, for studies of the tail-flick response in diabetic and non-diabetic mice. Intrathecal injection of substance P(1-7) amide produced prolongation of the tail-flick latency in both diabetic and non-diabetic mice, an effect that was more pronounced in diabetic mice than non-diabetic mice. Moreover, the observed antinociceptive potency of the substance P(1-7) amide was higher in both diabetic and non-diabetic mice in comparison with the native substance P(1-7). The antinociceptive effect of substance P(1-7) amide was reversed by naloxone but not by the selective opioid receptor antagonist ß-funaltrexamine, naltrindole or nor-binaltorphimine, selective for the µ-, δ- or κ-opioid receptor, respectively. In addition, the antinociceptive effect induced by substance P(1-7) amide was partly reversed by the σ(1) receptor agonist (+)-pentazocine, suggesting a possible involvement of the σ(1) receptor for the action of this peptide. These results suggest that the actions of substance P(1-7) amide mimic the effects of the native substance P fragment but with higher potency and that the mechanisms for its action may involve the σ(1) receptor system.

Development of walking analysis system consisting of mobile force plate and motion sensor.

In walking analysis, which is one useful method for efficient physical rehabilitation, the ground reaction force, the center of pressure, and the body orientation data are measured during walking. In the past, these data were measured by a 3D motion analysis system consisting of high-speed cameras and force plates, which must be installed in the floor. However, a conventional 3D motion analysis system can measure the ground reaction force and the center of pressure just on force plates during a few steps. In addition, the subjects' stride lengths are limited because they have to walk on the center of the force plate. These problems can be resolved by converting conventional devices into wearable devices. We used a measuring device consisting of portable force plates and motion sensors. We developed a walking analysis system that calculates the ground reaction force, the center of pressure, and the body orientations and measured a walking subject to estimate this system. We simultaneously used a conventional 3D motion analysis system to compare with our development system and showed its validity for measurements of ground reaction force and the center of pressure.

Prosthetic hand control using motion discrimination from EMG signals.

In this report, we improve the motion discrimination method from electromyogram (EMG) for a prosthetic hand and propose prosthetic hand control. In the past, we proved that a motion discrimination method using conic models could discriminate three hand motions without the incorrect discriminations that the elbow motions cause. In this research, to increase discrimination accuracy of motion discrimination using conic models, we propose a feature extraction method using quadratic polynomials. Additionally, because many prosthetic hands using motion discrimination have constant motion speed that can't be controlled, we propose an angular velocity generation method using multiple regression models. We verified these methods by controlling the 3D hand model. In the experiment, the proposed method could discriminate five motions at a rate of above 90 percent without the incorrect discriminations that elbow motions cause. Moreover, the wrist joint angle of the 3D hand model could be controlled by standard variation of 3[deg] or less.

Development of prosthetic arm with pneumatic prosthetic hand and tendon-driven wrist.

Recently, various prosthetic arms have been developed, but few are both attractive and functional. Considering human coexistence, prosthetic arms must be both safe and flexible. In this research, we developed a novel prosthetic arm with a five-fingered prosthetic hand using our original pneumatic actuators and a slender tendon-driven wrist using a wire drive and two small motors. Because the prosthetic hand's driving source is comprised of small pneumatic actuators, the prosthetic hand is safe when it makes contact with people; it can also operate flexibly. In addition, the arm has a tendon-driven wrist to expand its motion space and to perform many operations. First, we explain the pneumatic hand's drive mechanism and its tendon-driven wrist. Next, we identify the characteristics of the hand and the wrist and construct a control system for this arm and verify its control performance.

Hand motion discrimination by EMG signals without incorrect discriminations that elbow motions cause.

The objective of this research is to develop a hand motion discrimination method that uses electromyogram (EMG) signals for controlling myoelectric prosthetic hands without the incorrect discriminations that elbow motions cause. We proposed a method that can discriminate hand motions using linear multiple regression models in the past. However, this method incorrectly discriminates hand motions when elbow motions are performed. The incorrect discriminations hamper myoelectric prosthetic hand use. To solve this problem, we propose a hand discrimination method using conic models. In the experiment, we prove that the proposed method can discriminate hand motions without the incorrect discriminations.

Development of robot hand with pneumatic actuator and construct of master-slave system.

Recently, research has concentrated on robots that can coexist with people and be of use to them. Such a robot needs to be both safe and flexible. Here, we use a pneumatic actuator as the driving source of a robot hand. We develop a pneumatic actuator driven by low pressure because we consider that the conventional pneumatic actuator is inadequate for the driving source of a robot hand. First, we examine the characteristics of our new pneumatic actuator. Next, we develop a five-fingered robot hand using this pneumatic actuator. The robot hand produced is both safe and flexible. We construct a master-slave system to enable the robot hand to perform the same operations as a human hand. Next, we make a joint model that has one degree of freedom using a pneumatic actuator. We construct a control system for the joint model and verify its control performance.

Hand motion estimation by EMG signals using linear multiple regression models.

The purpose of this research is to construct an intelligent upper limb prosthesis control system that uses electromyogram (EMG) signals. The signal processing of EMG signals is performed using a linear multiple regression model that can learn parameters in a short time. Using this model, joint angles are predicted, and the motion pattern discrimination is conducted. Discriminated motions were grip, open, and chuck of a hand. Predicted joint angles were multi-finger angles corresponding to these three motions. In several experiments we proved the usefulness of processing EMG signals with a linear multiple regression model.

Development of measuring system to measure standing pose of the foot using distributed triaxial force sensor.

The bottom of a person's foot grips the floor for balance, and the action force and action moment work at the foot bottom when he maintains posture and when he moves. They are important indices in the evaluation and the medical attention of standing pose balance and gait disturbances. A lot of equipments to measure the floor reaction force have been researched. However, no floor reaction force meter exists that can measure distribution information force in three directions. This paper aims at the development of a system that can measure the standing pose of the foot that exists from a measuring instrument and that can measure the standing pose of foot distributed 6times4 three axis force sensors and software that displays and preserves the output of the sensor element. A time change of force that worked at the foot bottom is sought as a vector by outputting each sensor element. Moreover, an action vector is three dimensionally displayed whose data can be intuitively understood. The results of experiments show that the measuring system can measure the action force of the foot bottom as distribution information on force in three directions.

Metronomic scheduling of a cyclic hexapeptide Ra-VII for anti-angiogenesis, tumor vessel maturation and anti-tumor activity.

RA-VII, a cyclic hexapeptide isolated from Rubiae radix, binds to actin, causing a conformational change in the actin molecule and inducing G2 arrest by inhibiting cytokinesis. Here we examined the effect of RA-VII, its water-soluble derivative, and related RA-III and RA-V on endothelial cells. Among the four compounds tested, RA-VII most potently inhibited angiogenesis-related properties of endothelial cells (i.e. migration and proliferation) in vitro. We confirmed the anti-angiogenic activity of RA-VII in vivo by using a mouse corneal model. We then applied RA-VII for the treatment of tumors in mice. Daily intraperitoneal injection of RA-VII (1.5 or 3 mg/kg/day) exhibited no toxic effect on the animals, but significantly and dose dependently inhibited the growth of Lewis lung carcinoma cells previously inoculated into the mice. Interestingly, although two doses of RA-VII decreased the tumor vascular area to a similar extent, a higher dose of RA-VII led to tumor vessel maturation together with a significant increase in tumor cell apoptosis. Also, RA-VII showed a cytotoxic effect on Lewis lung carcinoma cells. These results indicate that metronomic scheduling of RA-VII is efficient for cancer treatment. A careful dose setting of RA-VII is crucial to obtain therapeutic superiority, possibly through tumor vessel maturation and a better distribution of the compound in the tumor tissue.