To improve the transcutaneous fluorescent image of an animal body, we derived a point-spread function (PSF) at a cylindrical surface of a turbid medium. In this technique, distortion problem of the restored shape was remained. For this problem, new scattering suppression technique using the PSFs divided into the symmetric and asymmetric components was developed. The usefulness of the proposed technique was verified in experiment with biological tissue. Figure 1 shows the result of 3D reconstruction. The internal fluorescent object, which is hardly seen in Fig. 1(b), became visible by the proposed technique. Through this analysis, the applicability to the biological tissue was verified.

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To attain high spatial-resolution in transillumination imaging, a new technique was developed to estimate the depth of the absorber in turbid medium by convolving a point spread function (PSF). We choose two wavelengths at which the optical properties of the medium are different. The transillumination image at one of the wavelength is convolved with the PSF of another wavelength. Two images are compared while changing the depth of the PSF. We can obtain the correct depth that gives minimum difference between the two images. The effectiveness of the technique was verified. Figs. 1-2 show the results of the depth estimation and the deconvolution with the PSF of the correct depth, respectively.

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We have introduced an inverse filtering algorithm to suppress undesirable effects of skin circulation in NIRS imaging with multi-distance probing system. We compared the performance of inverse filter by simple regularization (SR), that by sensitivity-adaptive regularization (SAR), and conventional simple back-projection (SBP). For this simulation, observation data contains target signal at 10 mm depth, which corresponds to perfusion change in the brain cortex, and disturbance signal at 2 mm depth, which corresponds to perfusion change in the shallow skin layer with additional Gaussian random noise. We calculate CNR from the filtered and unfiltered back-projection images. SBP method has the best CNR when there is no disturbance signal in the shallow plane but generates serious ghost noise when there is small signal in shallow plane. SR imaging can eliminate the ghost noise but yields worse CNR than the SBP method, whereas SAR imaging eliminates the ghost noise without serious CNR degradation.

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The purpose of this study is to measure the magnitude and direction of the fingertip contact force without any sensors between the object and the finger pad. The authors focus on the color change of each part of the nail from red to white depending on the magnitude and direction of the force applied to the finger pad and measure color distribution of the nail surface by optical sensor on the nail.In this paper, the authors install the sets of LED and photodiode in device and measure nail color distribution. From the distribution of color change of the nail, the direction of fingertip contact force is estimated with the primary calibration result of the relationship between color distribution and direction of the force.

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Stuttering is a developmental disorder of speech fluency. It is known that stuttering speakers can fluently speak when they speak by themselves, but stuttering appears well when they speak under face-to-face condition. This phenomenon is well known but the mechanism is still unclear. In general, vocal communication in the face-to-face condition is under stress in some degree. This stress may have influence on speech motor control. In this study, we attempted to construct the experimental setup for face-to-face communication in MRI condition. There were four conditions; 1) question by another participant in console room, 2) question presented on the screen, 3) look a face of another participant, and 4) a rest condition. Preliminary results showed that there were difference of neural activity between conditions in the fusiform gyrus, motor or sensory areas.

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Evaluation methods of anti-fatigue effects of functional foods are based on animal experiments. We propose a direct and simple method which verifies the anti-fatigue effect of functional food in human subjects. We perform double-blind placebo-controlled trial. This method adopts a simple method which consists of two stages in order to suppress such influences as much as possible. Subjects were 17 healthy male volunteers. They consumed anserine or water which was expected to have an anti-fatigue effect and performed the isometric foot exercise two times in one experiment. MDF were calculated from EMG recorded in the first and second exercise. We compared the difference of the two slopes or the angle between these slopes (AFI). The AFI for water was significantly larger than that for anserine. We think this method is easy and promising in the evaluation of anti-fatigue effect of functional foods.

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The purpose of this study is to identify a mechanomyogram system of the tibialis anterior muscle without electrical stimulation. A subject sat on a chair and his thigh and leg were immobilized with nylon belts. Ag-AgCl electrodes were attached on the skin over common peroneal nerve. An electric condenser microphone was attached on the skin of tibialis anterior muscle to measure a mechanomyogram. The subject was instructed to generate dorsiflexion torque like twitch contraction. The neural action potential and mechanomyogram were measured and the transfer function between them was identified using the subspace state space system identification method. The system was approximated with the third-order model. The natural frequency of the system was around 2 to 3 Hz and agreed with those estimated using electrical stimulation. The proposed technique provided novel method to identify the transfer function without electrical stimulation.

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The purpose of this study is to clarify the elasticity of the anterior tibial muscle from an evoked mechanomyogram (MMG) and dorsiflex torque in isometric contraction. Electrical stimulation was applied to the common peroneal nerve in a resting state and an isometric contraction (5, 10, 20, 30% MVC). An MMG and dorsiflex torque were measured with an acceleration sensor and strain gauge load cell, respectively. Superimposed MMG and torque were extracted and their systems were identified using a singular value decomposition method. The natural frequency of the system was calculated from the poles of the transfer function.
In conclusion, the transfer function of superimposed MMG and dorsiflex torque were well identified with sixth- and second-order model, respectively. The natural frequency increased as the contraction level increased. It was concluded that the muscle elasticity was revealed by estimating the natural frequency of the MMG system.

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The purpose of this study is to investigate the relation between stiffness and the elbow joint angle. Mechanomyogram (MMG) was recorded from biceps brachii muscle at three different elbow angles: 90, 120 and 150 degree. The biceps brachii muscle was electrically stimulated and its mechanomyogram was measured with an acceleration sensor attached to the skin of the belly of the biceps brachii muscle.The transfer functions from the stimulation to the MMG was identified by the singular value decomposition method, and natural frequency were derived from the transfer function. As a result, MMG was approximated with a fourth-order model. The lowest natural frequency increased as the elbow joint angle increased. It was concluded that biceps brachii muscle stiffness increased as the elbow joint angle increased.

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The purpose of this study was to develop a measurement system for evoked mechanomyogram (MMG) in cycling exercise.
Ergometric cycling was performed under two work-loads (60 W and 90 W) at pedal rate of 60 rpm. When a subject extended his knee to a 80 degree angle, electric stimulus was applied to the vastus lateralis muscle every twice, and an MMG was measured with a condenser microphone. The system of MMG were identified using a singular value decomposition method. The natural frequency of the system was calculated from the poles of the transfer function.
In conclusion, the transfer function of evoked MMG were well identified with the third-order model. The natural frequency increased as the work-load increased. An evoked MMG in cycling exercise could be measured with the developed system.

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A mechanomyogram (MMG) reflects visco-elasticity of the muscle. The MMG evoked with single pulse (SP) stimulation dominantly reflects the mechanical properties of the slow muscle because of around 80% of slow muscle fibers in the anterior tibial muscle. In this study, MMGs of the muscle are evoked with double pulse (DP) stimulation. With the second evoked pulse, fast muscle fibers dominantly contract because contractile velocity of these fibers is faster than that of slow muscle fibers. The MMG system with SP stimulation was approximated with the third-order model. On the other hand, the MMG system with double pulse stimulation was approximated with fifth-order model because the MMG amplitude of the slow muscle was relatively surppressed with the short stimulation interval. It means that the proposed method is a novel technique to estimate the stiffness of the fast muscle.

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In this study, we use SEMG(Surface EMG) that can be derived from the skin surface in order to develop the system which can operate an artificial hand like as a human hand. The new grip power display which uses a manchette in order to display the grip power by air pressure has been experimentally developed. And then based on analyzed results our new grip power display presents grip power of a robot hand as the air pressure of a manchette. In this paper, we will describe about our new developed system and the results of experiments using our new system.

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Our objective of this study is the development of a perfect voice recognition system using multi-SEMG that are measured from the human neck. In order to establish this objective a SEMG analyzing system is experimentally developed. In this paper, we will talk about the voice recognition results using this system. Actually, we conducted experiment which investigated whether this system can distinguish vowel and consonant. In this experiment, we used 4 channel SEMG measured from subject's neck. Positions of electrodes were determined using our developed Monte Carlo method. This method is able to select suitable positions of electrodes to detect pronounced voice. An experiment was carried out to see whether Japanese 50 pronunciations were distinguished each other using our developed method. In this paper we will talk about the results of this experiment.

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EMG measured from the skin surface is widely used as an information source to determine various types of body movements, and there are many research results using forearm EMG to detect hand motions. In this filed, detected results are used in order to control some equipments like as an artifical hand. However most of them only can detect hand motions and cannot detect muscle power for each motion. If the power that is generated from muscle is able to be estimated by measured EMG, estimated results will be useful to control equipments. In this paper, we talk about our developed method that can estimate muscle power of supination and pronation of a hand.

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We developed an unsupervised classification algorithm of Steady-State Visual Evoked Potential-based-Brain Computer Interface. The algorithm consists of (1) Spectrum Method, (2) Averaging Method, and (3) Combined Method of (1) and (2). Spectrum Method detects the frequency which gives the maximum difference of spectrum power between maximum (±0.1Hz) and median (±0.3Hz) of each frequency band corresponding to the flickering light stimuli. Averaging Method uses the peak-to-peak amplitude of visual evoked potential by dividing and averaging the raw EEG data with different cycles corresponding to the flicker frequencies. Combined Method adopts Spectrum Method in case that signal-to-noise ratio of the spectrum power is large enough, and otherwise adopts Averaging Method. The mean accuracy of the developed algorithms in 3-class classification with 32 subjects were 63.6%, 74.2%, and 74.3% with Spectrum Method, Averaging Method, and Combined Method, respectively, which were significantly larger than that using conventional Linear Discriminant Analysis (51.3%).

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Event-related potential (ERP) measured at 14 electrodes was discussed to quantify subjective evaluation, when judging the degree of preference for 5 pictures of different animals with 3 opinions; 1st preference, 2nd preference, and Others. Eleven subjects participated. P300 area surrounded by an ERP waveform of 250-600 ms is calculated, and normalized by maximum value for each subject. The result at Pz is shown in Figure. P1 to P5 indicate the order of subject's preference by questionnaire after the experiment. P300 area for P1 and P2 (the cases of animal which a subject likes) is larger. But the area for P4 and P5 is also large, indicating a response for animals which a subject dislikes.

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Recently, Brain-Computer Interface (BCI) research for Character input interface by using electroencephalography (EEG) has been actively conducted. P300 evoked by visual stimuli is generally used for character discrimination. However, P300 is mostly buried in spontaneous EEG and the component is usually estimated by summing up a large number of responses to reduce spontaneous EEG. In this research, we tried to extract P300 from a single response. Assuming that observed waveform is composed of three components: evoked component including P300, spontaneous EEG and noise, we estimated them by particle filter. Here, we constructed state space model by approximating evoked and spontaneous EEGs as second order trend model and autoregressive (AR) model, respectively. To evaluate our method, we performed the simulation experiment. As a result, on the error of estimated P300 and its peak amplitude, our method showed higher performance compared to conventional averaging method in small number of averaging times.

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Recognition of the environment causes insensible and conscious responses, and finally it changes our body resulting in a certain output to the world. However, little is known about its process in brain. This paper studied the influence of the gustatory stimulation on brain activity by an auditory oddball task. Subjects were healthy university students (n=6) with healthy sense of taste. Erythritol (60vol%) was used as a sweet taste and turmeric as a bitter one (2.9vol%). The latency of P300 component was shorter in bitter taste than that in sweet one (p< 0.05, paired t-test). We think that the better taste raises the alert level and accelerates the information processing of sound in brain.

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Our final Goal is to develop brain computer interfaces (BCIs) by the steady-state visual evoked potential (SSVEP).The BCI on SSVEP is used as a switching device. Therefore, many researchers do not focus on the SSVEP in long-term recordings. However, the SSVEP is not always generated in watching flashing visual stimuli. In this research, we focus on the SSVEP in long-term recordings and relationship between SSVEP and eye blink.In this research, we showed flashing visual stimuli. Frequencies of these stimuli are 15 and 20 Hz. Subjects are 3 males. The visual stimuli are shown during 60 [sec].As results, we confirmed that SSVEPs is not always generated and the power of SSVEPs has fluctuation. Next, we confirmed relationship between powers of SSVEPs and eye blink. In 1 [sec] later from eye blink, powers of SSVEPs increased more than the power before eye blink.

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In present study we investigate the EEG response of patient with Severe Motor and Intellectual Disabilities. Patients with Severe Motor and Intellectual Disabilities (SMID) is a term of a heterogeneous group of disorders with severe physical disabilities and profound mental retardation which is caused by a disturbance of central nervous systems. Their caregivers have problems understanding patients' responses and catching their attention because it is difficult to communicate verbally with patients. When caregivers called their own name, some patients with SMID show a smiling, eye blinking and so on. It seems to suggest that these patients recognize their own names from their response however, there is no scientific evidence. To understand their response activities, we investigate their brain activity by measuring and analyzing EEG. We measured EEG of patients with SMID during hearing their own names and analyzed to compare their response with that of normal subject group.

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In standard finite element analysis in structural dynamics, meshing can affect computation results. However, there have been no detailed report about effects of meshing on results of coupling simulation of left ventricular wall motion which involves myocardial spontaneous contractile force and fiber orientation. In this study, we examined an effect of meshing on simulation of left ventricular wall motion, which couples precise ventricular myocyte model and myocardial fiber orientation. We compared two shape models; spheroid mesh divided along graticule and spheroid mesh subdivided from a semi-regular polyhedron. The comparison results show significant differences between two models around the ventricular apex, which are mainly caused by the contractile force and the fiber orientation.

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Human induced pluripotent stem cell (hiPSC)-derived neurons may be effectively used for drug discovery and cell-based therapy. However, the immaturity of cultured human iPSC-derived neurons and the lack of established functional evaluation methods are problematic. We here used a multi-electrode array (MEA) system to investigate the effects of the co-culture of rat astrocytes with hiPSC-derived neurons. The co-culture facilitated the long-term culture of hiPSC-derived neurons for >3 months and long-term spontaneous firing activity was also observed. After >3 months of culture, we observed synapse transmission. Compared with rat neurons, hiPSC-derived neurons required longer time to mature functionally. Furthermore, addition of the synapse antagonists induced significant changes in the firing rate. In conclusion, we used a MEA system to demonstrate that the co-culture of hiPSC-derived neurons with rat astrocytes is an effective method for studying the function of human neuronal cells, which could be used for drug screening.

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Neuronal cells can be generated from Human induced pluripotent stem cells (hiPSCs), providing a very important alternative to studies of humans and model organisms, to facilitate a better understanding of the mechanisms of neurological diseases and identifying novel therapeutic avenues. However, the functional assays of cultured human iPSC-derived neurons have not been established. Here, we have developed the noninvasive and real-time cell sensing techniques of three fundamental function (1) action potential, (2) neurotransmitter release, and (3) post synaptic potentials. These techniques may be beneficial for clarifying the functions of human neuronal circuits and for drug screening applications.

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Cell delivery is a critical step in the process of repairing damaged tissues. Age-related macular degeneration (AMD) is the leading cause of visual impairment and blindness in the elderly population, whose main complication is the development of subretinal choroidal neovascularization. Sbretinal transplantation of RPE cells to the degenerated and damaged site has attracted a great deal of attention as a relatively new approach for treating AMD. However, poor survival, distribution and integration of transplanted RPE cells to the subretinal space have limited this approach. In the meantime, development of a minimally invasive surgical procedure would bring significant benefits both to surgeons and patients. In this study we developed a micropatterned biodegradable nanosheet as a supporting material for culturing and transplanting RPE cells to the subretinal space.

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Solubilized liver-specific extracellular matrix (ECM) as a functional culture substratum was evaluated in this study. Briefly, the various types of solubilized ECMs were prepared from decellularized liver with HCl of various concentrations. The concentration of HCl affected the molecular structure of the solubilized ECMs. On the other hand, the level of albumin production from hepatocytes cultured on the solubilized ECMs films were higher than that of type I collagen film. However, the differences of cell adhesive tendency and albumin production of hepatocytes were could not be observed among various ECMs. Therefore, liver ECM composition is effective as a hepatocyte culture substratum.

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This paper reports the development of a palm-size device called "i-PASMA (integrated Pressure Actuated Shapable Microwell Array)" for formation, evaluation and collection of embryonic bodies (EBs). By incorporating a transparent heat film, water evaporation chamber and CO2 generation reagents, i-PASMA realized miniaturization of the whole process of EB experiments in one chip without a conventional big incubator. By putting this system under the microscope, EB fabrication process from human induced pluripotent stem cells (hiPS cells) were successfully observed. The massively parallel analysis system "i-PASMA" should accelerate the regenerative medicine as a total EB research platform.

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We found a unique cell membrane perforation method which is applying photochemical oxidation on a limited area of cell membrane, with high survival rate. We recently developed a photosensitizer included nano needle array perforator for mass cell processing and the robotic processing system. The system had still some instability but in this study, we modified the whole system to improve the mechanical accurancy.The perforator is processed by nanoimprint, with a novel fine mold. The material is silicone polymer including photosensitizer Hematoporphyrin and iron oxide for magnetic connect to the processor. The dimensions of the needle are follows: diameter and hight 1.7μm, pitch 3.0μm. Excitation light is blue bandpass filtered 100W mercury lamp beam. With the system, we could inject membrane impermeable fluorescent dye AlexaFluor594 to rat PC12 cells and Human coronary artery endothelial cells. We will improve the system for various applications, e.g. transgenic process etc.

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We have developed the blood contacting surface materials based on the titanium(Ti) micro-porous structure for promoting neointimal growth. The purpose of this study is the evaluation of micro porous structure and materials' properties.Ti powders were mixed with the thermoplastic wax and adjusted in 50 degC for making the injectable paste into the mold. The green specimens were sintered at 1,100 degC. These specimens were studied on mechanical strength tests and the cell adhesion evaluation. And these were also implanted around connective tissues and muscular in rat.The value of porosity and pore size were similar just the estimated value in design. The mechanical strengths and cell adhesion showed the adequate results for applying as the blood contacting surface materials. The tissue adhesion on animal experiments showed the advantages compared to bulk Ti after several weeks. These results indicated the possibility for promoting neointimal growth as the blood-contacting applications.

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Diamond-Like Carbon (DLC) films have excellent properties such as hemocompatibility, biocompatibility, and in-vivo stability. However, the properties of DLC films strongly depend on deposition conditions, fabrication equipments and deposition methods. To produce a required film, it has to be carefully selected a manufacture method and a preparation condition. In this study, biocompatibility of DLC films deposited by several kinds of equipments was estimated by the cell culture, and the correlation with DLC film surface state was investigated.By several kind of equipment, 19 types of DLC films were deposited on PS dish. We estimated biocompatibility and surface state about these DLC films.We found that there was no correlation between biocompatibility of DLC films and the result of XPS, or that of contact angle measurement. However, there was strong correlation between biocompatibility and hardness test. This result shows hardness test assesses biocompatibility of DLC films.

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Hydrogenated amorphous carbon films (a-C:H) have electrical, mechanical, and chemical properties. The combination of these properties makes many applications available for a-C:H film coatings as a medical devices. In this study, in order to investigate blood compatibility of a-C:H film coating (cytocompatibility type), a-C:H film coating segmented polyurethane scaffold fiber sheet (a-C:H-Scaffold) was implanted at partial aorta descendens of a goat for 35 days. The scaffold sheet was fabricated by electronspinning method, and the a-C:H film was deposited on the scaffold sheet by r.f. plasma chemical vapor deposition (CVD) method. In the in-vivo test, it was observed that the a-C:H film coating surface was uniformly covered by neointima. Additionally, the surface had no thrombus formation as an inflammatory reaction and it was shown that the a-C:H film coating had a good blood compatibility. These results suggest that a-C:H film coating has emerged as a potential technique for blood interfacing applications.

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Chitin nanofibers (CNF) are nontoxic biomaterials, biodegradable and large surface-to-mass ratio. Thus they are widely applied as pharmaceutical composite materials. This study aimed to develope a composite of CNF and silver nanoparticles (Ag NPs) as the antimicrobial materials for wound dressing applications. The chitin sheets contained nano-scale fiber on suface structure were used to make composites with Ag NPs (size: ~5.17 nm). The composites were characterized by transmission electron microscope (TEM) and then tested against Escherichia coli and Pseudomonas aeruginosa, the most widespread infectious wound bacteria. The ultrathin sectioning of bacterial cells was also carried out to observe the batericidal mechanism of Ag NPs. The TEM images indicated that the Ag NPs are dispersed and tightly absorbed onto CNF sheet. The composites sheet with Ag NPs showed strong antimicrobial properties. The current results suggest that it is possible to apply CNF sheet with Ag NPs as an anti-infectious wound dressing.

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Orthodontic tooth movement is achieved by the process of repeated alveolar bone resorption by osteoclast. On the other hand, orthodontic force-induced root resorption by odontoclast leads to serious problem. We established mechanical loading induced tooth movement mouse model in which a Ni-Ti coil spring was inserted between the upper incisors and the upper first molar. Macrophage colony-stimulating factor (M-CSF) is essential for osteoclastogenesis and odontoclastogenesis. We examined the effect of neutralization of M-CSF on the mechanical loading induced osteoclastogenesis and odontoclastogenesis in the mouse model. Mice were injected locally with M-CSF neutralization antibody during mechanical loading induced tooth movement. The number of osteoclasts and odontoclasts was counted in the horizontal sections of the upper first molar after staining with TRAP. The neutralization of M-CSF significantly inhibited osteoclastogenesis and odontoclastogenesis. These results suggested that the neutralization of M-CSF might be useful for controlling orthodontic tooth movement and root resorption.

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While embryonic cardiomyocytes actively proliferate, this activity is lost shortly after birth in mammals, the mechanisms of which are unknown. At birth, cardiomyocytes are exposed to dramatic changes, including 1) abrupt elevation of oxygen tension by the onset of breathing (PaO₂: 20mmHg to 100mmHg), 2) temporary starvation due to the loss of maternal blood supply, and 3) drastic hemodynamic changes. Here we focused on the effect of 1). The exposure of fetal mouse cardiomyocytes to atmospheric O₂ (20%) inhibited cell proliferation which was evaluated by cell counting and Ki67 expression, suggesting increased O₂ exposure at birth is fundamental for cell cycle exit. To identify the critical genes, microarray was performed with two sample sets, i.e. fetus vs neonate, and fetal cardiomyocytes cultured under 3% vs 20% O₂. We identified 53 genes showing the common expression profile in the two arrays, and are now exploring each phenotype by knock-down experiments.

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Na⁺/Ca²⁺ exchanger (NCX1) is essential Ca²⁺ regulator of myocyte Ca²⁺ homeostasis and specially localized at transverse tubules (T-tubules) membrane. T-tubules are invaginations of the sarcolemma and critical for myocyte contraction, especially as the main site of excitation-contraction coupling. Therefore, T-tubule disorganization is linked to decreased contractility in heart failure, but the molecular mechanism is not clear. We analyzed the alteration of T-tubule structure and Ca2+ handling during the progression of heart failure after transverse aortic constriction (TAC)-surgery, using cardiac-specific and inducible NCX1 transgenic mice. In progression of cardiac dysfunction, sarcoplasmic reticulum Ca²⁺ ATPase and NCX1 activity were down-regulated before T-tubule disorganization. The inducing NCX1 overexpression after TAC-surgery prevented T-tubule disorganization and contractile dysfunction under prolonged pressure-overload, with improvement of myocyte Ca²⁺ handling. These results suggest that local Ca²⁺ control beneath the T-tubule membrane is crucial for the maintenance of myocyte structure and function, in which NCX1 has a pivotal role.

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We recently reported that stimulation of a peripheral sympathetic nerve fascicle via a microelectrode, i.e. microstimulation, transiently reduced blood glucose (BG) in rats in case that its intensity was set to induce small muscle contraction (MC). The reduction could be attributed to the enhancement of peripheral glucose uptake (GU). We then found that the peripheral sympathetic nerve activity can be enhanced with microstimulation intensity lower than the MC threshold (MCT). In the present study, therefore, effects of the microstimulation on BG and plasma insulin (PI) were evaluated with intensity lower than or equal to (MCT-0.05) V. The results showed that BG successfully decreased in 30 s and returned toward the baseline thereafter, as seen in the previous study shown above, with little change in PI. They suggest that the microstimulation could increase peripheral GU to reduce BG without MC, and that the function could be non-insulin dependent.

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MDPC-23 cells were incubated with ZnCl₂ and the levels of HO-1 protein, phosphorylated forms of mitogen-activated protein kinases (MAPKs), including extracellular signal-regulated protein kinase (ERK), c-Jun NH₂-terminal kinase (JNK), and p38 were determined with western immunoblotting.The level of HO-1 mRNA was determined with RT-PCR analysis.After pretreatment with inhibitors of MAPKs, HO-1 protein level was determined in MDPC-23 cells exposed to ZnCl₂.Following exposure to 500μM ZnCl₂, the levels of both HO-1 mRNA and protein were markedly increased.The phosphorylated forms of MAPKs increased after ZnCl₂ exposure.Furthermore, the expression of HO-1 was markedly suppressed by treatment with the p38 inhibitor, SB203580, and mildly suppressed by the MAPK/ERK kinase inhibitor, U0126.However, treatment with the JNK inhibitor, SP600125, did not suppress ZnCl₂-induced HO-1 expression.These results suggest that ZnCl₂ exposure induces HO-1 expression via multiple intracellular signalling pathways,including p38,ERK in this odontoblast-like cell lines.

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Recently, though treatment to inject activated cells to a patient is popular, there're some side effects and limitation of accumulation efficiency, because the cells spread in bloodstream. Therefore, we have previously reported our attempts for active control of microbubbles (MBs) by using Bjerknes force. In this study, we examined the method to form aggregations including cells (lymphocyte) derived from a rat. After the injection of the MBs and cells, we emitted ultrasound with frequency of 5 MHz and sound pressure of 300 kPa-pp. Figure shows the comparison of aggregations without cells. We estimate cells were included in aggregations, which can be predicted the controllability of cells.

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We have studied control of microbubbles(MBs) using ultrasound for medical applications. In trials for inducement of MBs, the tolerance of radiating point was as small as 1.5 mm. Considering the motions of the human body, to apply in vivo may be difficult. Thus, using 2D-array transducer, we tried design and examination of acoustic fields which have wider MBs control region. We used Y-shaped channel and radiated 4 patterns of single-focus acoustic field, aims each of the 2 x 2 points with pitch of 2.5 mm, by time division with 1 ms intervals. Result, designed acoustic field could have the tolerance of radiating point of 6 mm. MBs control region might be expanded by time division method.

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The purpose of this research is to demonstrate a new design for a mass sensor with a circular resonator that is free of power supply lines. A line-free mass sensor comprises a resonator and a piezoelectric element for vibrating it. Since electric power is used to actuate the piezoelectric element, the resonator is free from power lines. Target molecules become attached to the resonator changing its resonant frequency. The geometric shape and dimensions of the resonator were designed by the finite element method. The resonator was fabricated with the shape of circular plate of diameter 4 mm by photolithography, so that the radial directional oscillation primary mode of vibration would be 3.68 MHz. The concentrations of glucose solution were measured using the line-free mass sensor. The sensitivity of the line-free mass sensor was estimated to be 8 fg when a frequency resolution of 0.1 Hz was used.

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Immunosensor is one of the most expected devices for diagnosis. In spite of the intensive efforts, however, practical use of immunosensor is yet to be realized. The largest prevention is the surface adsorption of non-specific molecules. Especially in case of biological specimen, contamination is inevitable. Because of the high background noise, many kinds of sensing scheme have failed to detect antigen-antibody reaction. In this study, fluorescence anisotropy measurement was employed to detect the antigen- antibody binding without disturbance of contamination. With this method, molecular motion change of a molecule can be measured free from the surface adsorption. Sensor substrates were fabricated by immobilizing fluorescent labeled antibody. Anisotropy change by the administration of antigen was measured. Fluorescence anisotropy changes of 9 specimen were 0.03-0.06, while the original anisotropies were scattered over 0.1-0.3. Antigen binding was also confirmed even with existence of 10μg/mL BSA. These results suggest the possibility of this sensor.

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We formed 64 microelectrodes and multiple microholes on a transparent SiN (silicon nitride) diaphragm, and developed a microdevice for measuring extracellular potentials of cultured cells and tissues. The microholes permits supply of nutrients and release of stimulating factors for various cell analyses. The 8 x 8 square-shaped microelectrodes which measure 54 µm on a side and are made of Pt black were located at the center of culture well bottom made of a SiN diaphragm of 2 µm in thickness. Also, transparent leads made of ITO were buried in the SiN diaphragm in order to connect the microelectrodes and bonding pads located at the device edge. Moreover, the microholes of 5 µm in diameter were opened in the spaces where neither electrodes nor leads exist on the SiN diaphragm. Using the device, we succeeded in detecting electrical signals from a rat hippocampal slice by chemical stimulation through the microholes.

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We have developed optically driven nano-beam for sense cellular proteins elasticity. It has a movable plate attached to end of thin beam extended from base. The plate can be move to and fro by optical tweezers. Additionally, the nano-beam has a fixed wall. When proteins are attached between the plate and wall, the nano-beam can analyze protein elasticity. In this report, we performed quasi-static experiment for measuring actin proteins elasticity using optically driven nano-beam capable of bonding cellular proteins only to its wall and plate realized by chemical cross-linker and silane coupling agent. According to this, we could indicate capability of mechanical analysis using the nano-beam.

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There is several way to measure biological osmotic pressure. These methods measure the average, pin point discrete osmotic pressure. The microscopic method using cellular images, but it is the average osmotic pressure inside of the cell. The measurement of optical spectroscopy which is good accuracy, however it is not expected time series and two-dimensional information. It is possible for the optical method according to the image to measure the continuous and changes the two-dimensional osmotic pressure difference. When the sealed vessel fixed the semi-permeable membrane is filled with the albumin solution stained with Bullet, the solvent moves into the vessel. As a result, the change of concentration of this solution in the vessel taken by a digital camera with liquid crystal tunable filter. We found that this brightness change with the law of Lambert-Beer, so we thought that it is possible to measure osmotic pressure in a small region.

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We present a newly developed microfluidic device which enables to measure ion concentrations even if the flow rate is small. A trial device was designed 2-inlets and 1-outlet Y-shaped channel. The external form was 25x55x5 mm. The device was fabricated using photolithography, PDMS, and glass plate. The differential sensor system which consists of two ion-sensitive field-effect transistors (ISFETs) for pH was inserted into the channel. The device was calibrated using three standard solutions (4.01, 6.86, 9.18). We evaluated the measurement error using same solutions and two diluted solutions. The measuring time was 150 sec and the sample solution was consumed 2.0 ml. The maximum measurement error of the standard solutions and diluted solutions were 0.04 and 0.16, respectively. These results indicate that the new device has a potential that several practical applications in medicine and biology are realized soon.

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This study aimed to minimize the external hip adduction and flexion torques by gait modifications. Since internal hip joint forces cannot be measured directly, the external torques at the hip were used to predict the internal joint forces. Despite the need for early treatment of the hip osteoarthritis, few clinical or physiological interventions slow the progression of the hip osteoarthritis. In this study, a commercially available three-dimensional musculoskeletal computer model and a normal gait data including kinematics and ground reaction forces were used. We used an inverse dynamics approach to calculate the hip adduction and flexion moment during gait. And a dynamic optimization approach was used to reduce these torques during gait by changing kinematics variables from the normal gait pattern. We got an acceptable gait modification that reduces peak adduction moment during gait compared to the normal gait.

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In order to evaluate the contraction performance of muscle, it is necessary to measure MMG and EMG signals simultaneously, because they are input and output signal for muscle contraction, respectively. In this study, we proposed a new evaluation method of isometric contraction of the quadriceps muscle by the MMG / EMG hybrid transducer which could measure MMG and EMG signal simultaneously. When we applied this transducer on the skin surface of the right leg of two subjects, they performed two types of knee extension isometric contraction with open kinetic chain. One was knee extension movement more than 600 [N] and the other was maximum voluntary contraction. The proposed muscle performance index (MMG/EMG) hardly changed in the former case, but gradually increased in the latter case because of muscle fatigue. Thus the new index was able to evaluate the muscle contraction and muscle fatigue numerically.

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Osteocytes produce various factors in response to mechanical stimuli. One such factor, CCN2 is thought to play a significant role in osteocyte responses to mechanical stimuli, but its function in osteocytes is not well understood. We analyzed chick osteocyte response to compressive force focusing on apoptosis and CCN2 by using our original culture device that can apply quantitative mechanical stimuli. Compressive force increased CCN2 gene expression and protein production, and induced apoptosis in osteocytes. Application of exogenous CCN2 protein induced apoptosis, and a neutralizing CCN2 antibody blocked loading-induced apoptosis. We further examined how CCN2 induce apoptosis in loaded osteocytes. In loaded osteocytes, ERK1/2 was phosphorylated, and an ERK1/2 inhibitor blocked loading-induced apoptosis. Application of exogenous CCN2 protein caused ERK1/2 phosphorylation, and the neutralizing CCN2 antibody inhibited loading-induced ERK1/2 phosphorylation. These results demonstrated that enhanced production of CCN2 in osteocytes under compressive force loading induces apoptosis through ERK1/2 pathway.

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Amniotic membrane (AM) is utilized in tissue engineering due to its advantages such as immune tolerance.However its mechanical characteristics has not been thoroughly investigated. In this study, we employed uniaxial tensile apparatus to investigate the directionality, viscoelasticity, and strength of porcine AM. The experimental results show that AM is isotropic but heterogeneous. The strength of the AM near placenta is 2.3± 1.0 [MPa], higher than those of all other portions. The coefficients of stress relaxation of the AM near placenta (λ₁=14.7± 4.7[s]; λ₂=37.3± 5.7[s]) is also the largest.

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In the 3D cell culture, it is necessary to construct optimum capillaries, which supply oxygen and nutrients for the cells. As we already reported the blood capillaries had been found that formed 5-20μm length in 3D scaffolds in optimum flow rate culture condition. The purpose of this study is the visualizing culture medium flow in 3D scaffold to recognize the process of the capillary network constructions in 3D scaffold. A small vascular graft that created 0.4mm holes at 5mm intervals in wall was sandwiched between the fibrous scaffold sheets. The visualizing particles were flowed to scaffold. The culture medium flow were captured as visualizing particle flow using high speed video camera(Hurricane-40/Photon focus, 640x480pixels, 100fps). The captured flow images were processed as Isochronal Map in offline and were compared with cultured capillary image measured by phase contrast microscope.

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The real time monitoring system of cell population behavior is required to noninvasively evaluate the cellular potential and the quality of the cell culture process. Cell tissues have been observed by using the phase-contrast image. However, the image processing has difficulty to extract individual cells in cell tissue with thickness. In this study, the observation system was developed for visualizing and measuring individual cells. The observation system was constructed with four white LED and CMOS camera. NIH3T3 cells inoculated at 0.8 × 10⁴ cells/cm² in 35mm dish were captured every 24 hour by using development system. Cell images were synthesized by using four cell images captured at each LED. The synthesis image could be enhanced contrast. In conclusion, the cell that was difficult to detect with one direction lighting was possible to observe on a clear cell image with four directions lighting.

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