509 research outputs found

    Development of vibration mechanical stimuli loading device for live cell fluorescence microscopy

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    Bone metabolism is regulated by mechanical stimuli such as gravity and exercise. If bone formation can be promoted by artificial mechanical stimulation, the quality of life of the aging society can be improved, such as by reducing the progression of osteoporosis and preventing patients from being bedridden. Micro-vibration stimulation with frequencies of 15 Hz to 90 Hz and acceleration amplitudes of 0.1 g to 0.3 g is effectively promotes bone formation in animal models. However, the mechanism of how these weak vibrations are sensed by bone cells and are used to regulate bone metabolism is unknown. In this study, we developed a device to apply micro-vibration stimuli to osteoblasts cultured on a glass bottom dish and observed the cell response to the stimuli using a confocal laser scanning fluorescence microscope. The device performance was confirmed using driving tests, and the calcium signaling response of osteoblasts to micro-vibration stimuli was observed in real time and in situ. The calcium signaling response characteristics of the cells differed when the cells were subjected to 45 Hz and 90 Hz micro-vibration stimuli, even under a constant acceleration amplitude of 0.2 g

    IoT measurements of the winter environment around Lake Izunuma, Miyagi

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    The Tenth Symposium on Polar Science/Ordinary sessions: [OM] Polar Meteorology and Glaciology, Wed. 4 Dec. / Entrance Hall (1st floor) , National Institute of Polar Researc

    Preference Analysis Method Applying Relationship between Electroencephalogram Activities and Egogram in Prefrontal Cortex Activities : How to collaborate between engineering techniques and psychology

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    This paper introduces a method of preference analysis based on electroencephalogram (EEG) analysis of prefrontal cortex activity. The proposed method applies the relationship between EEG activity and the Egogram. The EEG senses a single point and records readings by means of a dry-type sensor and a small number of electrodes. The EEG analysis adapts the feature mining and the clustering on EEG patterns using a self-organizing map (SOM). EEG activity of the prefrontal cortex displays individual difference. To take the individual difference into account, we construct a feature vector for input modality of the SOM. The input vector for the SOM consists of the extracted EEG feature vector and a human character vector, which is the human character quantified through the ego analysis using psychological testing. In preprocessing, we extract the EEG feature vector by calculating the time average on each frequency band: θ, low-β, and high-β. To prove the effectiveness of the proposed method, we perform experiments using real EEG data. These results show that the accuracy rate of the EEG pattern classification is higher than it was before the improvement of the input vector

    Evaluation of the histological and mechanical features of tendon healing in a rabbit model

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    Objectives This study aimed to evaluate the histological and mechanical features of tendon healing in a rabbit model with second-harmonic-generation (SHG) imaging and tensile testing. Materials and Methods A total of eight male Japanese white rabbits were used for this study. The flexor digitorum tendons in their right leg were sharply transected, and then were repaired by intratendinous stitching. At four weeks post-operatively, the rabbits were killed and the flexor digitorum tendons in both right and left legs were excised and used as specimens for tendon healing (n = 8) and control (n = 8), respectively. Each specimen was examined by SHG imaging, followed by tensile testing, and the results of the two testing modalities were assessed for correlation. Results While the SHG light intensity of the healing tendon samples was significantly lower than that of the uninjured tendon samples, 2D Fourier transform SHG images showed a clear difference in collagen fibre structure between the uninjured and the healing samples, and among the healing samples. The mean intensity of the SHG image showed a moderate correlation (R2 = 0.37) with Young’s modulus obtained from the tensile testing. Conclusion Our results indicate that SHG microscopy may be a potential indicator of tendon healing

    Unconventional internalization mechanisms underlying functional delivery of antisense oligonucleotides via cationic lipoplexes and polyplexes

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    There is mounting interest in developing antisense and siRNA oligonucleotides into therapeutic entities; however, this potential has been limited by poor access of oligonucleotides to their pharmacological targets within cells. Transfection reagents, such as cationic lipids and polymers, are commonly utilized to improve functional delivery of nucleic acids including oligonucleotides. Cellular entry of large plasmid DNA molecules with the assistance of these polycationic carriers is mediated by some form of endocytosis; however, the mechanism for delivery of small oligonucleotide molecules has not been well established. In this study, splice-shifting oligonucleotides have been formulated into cationic lipoplexes and polyplexes, and their internalization mechanisms have been examined by using pharmacological and genetic inhibitors of endocytosis. The results showed that intercellular distribution of the oligonucleotides to the nucleus governs their pharmacological response. A mechanistic study revealed that oligonucleotides delivered by lipoplexes enter the cells partially by membrane fusion and this mechanism accounts for the functional induction of the target gene. In contrast, polyplexes are internalized by unconventional endocytosis pathways that do not require dynamin or caveolin. These studies may help rationally design novel delivery systems with superior transfection efficiency but lower toxicity

    Introduction of Land Use Model to Improve Travel Demand Forecasting in a Metropolitan Area: Case of TRANUS Application to Sapporo

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    Building a GIS Platform for the Quantitative Approach to Regional Studies in Northeast Asi

    Electrochemical Assay for deoxyribonuclease I Activity

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    A thiolated oligonucleotide having three ferrocenes was immobilized on a gold electrode through the sulfur–gold linkage. This electrode showed a current response based on the redox reaction of the ferrocene moieties and this response was decreased after treatment with deoxyribonuclease I (DNase I), suggesting the disappearance of the ferrocene moieties on the electrode by the DNase I digestion. A linear correlation between i0 and i, which are current peaks before and after DNase I treatment, respectively, was observed and this slope was decreased with increase in the amount of DNase I. No current decrease was observed in the presence of EDTA or RNase A instead of DNase I. These results suggested that the current decrease responded specifically to the amount of DNase I and this electrode could be used for an electrochemical DNase I assay. Under the optimum conditions of DNase I digestion at 37 °C for 30 min, a quantitative analysis could be achieved in the range of 10−4–10−2 units/μl of DNase I
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