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Treatment of painful peripheral neuromas by vein implantation

Ryosuke Kakinoki, Ryosuke Ikeguchi, Taiichi Matsumoto, Makoto Shimizu, Takashi Nakamura
2002 International Orthopaedics  
Firstly, we designed a vein-implantation model using the rat femoral nerve and vein to study the morphometric changes in nerve endings inserted into venous lumina. By 4 weeks, nerve fibers had extended from the nerve stump into the lumen of the vein and along the endothelium of the vein. After 8 weeks, the lengths and number of nerve fibres extending into the vein lumen began to decrease. At 12 weeks, the nerve ending had developed a hemispherical shape. In none of the experiments was a neuroma
more » ... formed. Secondly, we treated ten neuromas in ten patients by the vein-implantation method. We obtained excellent results in seven patients.
doi:10.1007/s00264-002-0390-0 pmid:12582812 pmcid:PMC3673692 fatcat:gzdlnxjvmze3tcrazrmqo6tepm

Rare Event Detection using Disentangled Representation Learning [article]

Ryuhei Hamaguchi, Ken Sakurada, Ryosuke Nakamura
2018 arXiv   pre-print
This paper presents a novel method for rare event detection from an image pair with class-imbalanced datasets. A straightforward approach for event detection tasks is to train a detection network from a large-scale dataset in an end-to-end manner. However, in many applications such as building change detection on satellite images, few positive samples are available for the training. Moreover, scene image pairs contain many trivial events, such as in illumination changes or background motions.
more » ... ese many trivial events and the class imbalance problem lead to false alarms for rare event detection. In order to overcome these difficulties, we propose a novel method to learn disentangled representations from only low-cost negative samples. The proposed method disentangles different aspects in a pair of observations: variant and invariant factors that represent trivial events and image contents, respectively. The effectiveness of the proposed approach is verified by the quantitative evaluations on four change detection datasets, and the qualitative analysis shows that the proposed method can acquire the representations that disentangle rare events from trivial ones.
arXiv:1812.01285v1 fatcat:culwl26pffcvjl4s4c25jk5xdu

Surgical Skill Assessment via Video Semantic Aggregation [article]

Zhenqiang Li, Lin Gu, Weimin Wang, Ryosuke Nakamura, Yoichi Sato
2022 arXiv   pre-print
Supplementary Material for Surgical Skill Assessment via Video Semantic Aggregation Zhenqiang Li 1 , Lin Gu 2 , Weimin Wang 3 , Ryosuke Nakamura 4 , and Yoichi Sato 1 1 The University of Tokyo, Tokyo,  ... 
arXiv:2208.02611v1 fatcat:44i4dlyerbawfnad6d3flvhhry

Optimization and Performance Evaluation of Stereo-Matching Software on Many-core Processors

Kenji Iwata, Yoshio Tanaka, Ryosuke Nakamura, Tomoki Masuda, Ryosuke Machida, Isao Kojima, Satoshi Sekiguchi
2011 Procedia Computer Science  
The high-performance Geospatial Information System (GIS) is expected to provide an innovative infrastructure for Earth sciences, enabling near-real-time data and processing services. Stereo-matching software has often been used in generating a Digital Elevation Model (DEM) from a pair of satellite imagery data sets to compute height from a parallax views using two photographic images. There is a need to reduce the computation time required for processing large images. We optimize
more » ... software on multi-core/many-core processors, including Xeon, Cell and GPGPU. We describe optimization approaches of the correlation calculation part which occupied about 55% of the ovarall computation time. After porting and optimizing software for multi-core/many-core processors, we achieved processing time of 4.79 second (Xeon), 2.28 second (Cell) and 0.97 second (GPGPU) on each platform.
doi:10.1016/j.procs.2011.04.167 fatcat:2seasxmxozb35nvskmt7xc3khq

Nerve Regeneration Promoted in a Tube with Vascularity Containing Bone Marrow-Derived Cells

Tomoyuki Yamakawa, Ryosuke Kakinoki, Ryosuke Ikeguchi, Ken Nakayama, Yoshihide Morimoto, Takashi Nakamura
2007 Cell Transplantation  
INTRODUCTION: Artificial nerves have been considered as an alternative to nerve grafting, so as to bridge the interstump gap of peripheral nerves. Schwann cells are known to support nerve regeneration, but the difficulty is to obtain sufficiently large numbers of cells for clinical use. In order to circumvent this difficulty, there is the alternative of artificially inducing other cells to turn into Schwann cell-like phenotypes. Bone-marrow-derived cells (BMCs) are multipotent cells that have
more » ... e potential to differentiate into bone, cartilage, fat, muscle and neuronal lineage, including both neurons and glial cells depending on the environment in which the BMCs are cultured. BMCs transplanted into the intratubular space between nerve stumps are nourished by the capillaries. So, when the interstump gap is long, the intrachamber BMCs tend to be ischemic. The vascularity of the tubular lumen depends on capillaries extending from both nerve stumps to either end of the tube; in association with axon extension in tubulation, BMCs transplanted into the intratubular space are nourished by the capillaries. So, when the interstump gap is long, the intrachamber BMCs tend to be ischemic. In the present study, we focused our attention on the vascular as well as neurochemical environment within a tube. We created a silicone tube model containing BMCs and pedicled sural vessels with a 15 mm interstump gap in rat sciatic nerves. We investigated whether BMCs could survive within the silicone tube by obtaining oxygen and nutrients from the preinserted sural vessels and differentiate into cells expressing Schwann cell phenotypes, which would improve axon regeneration within the tube. METHODS: Primary BMCs were isolated from bone marrow of the femurs of inbred male Lewis (RT-1 l ) rats. Fibroblasts were isolated from skin dermis using collagenase and cultured. To confirm the differentiation potential of the BMCs obtained from donor Lewis rats, cells were cultured under conditions suited for either adipogenic, chondrogenic, or osteogenic differentiation. After 1 to 3 weeks in lineage-specific culture conditions, the BMCs were highly differentiated to cells with adipogenic, chondrogenic and osteogenic phenotypes. A silicone tube model containing reverse-pedicled sural vessels was created in the sciatic nerve of Lewis rats. About 1 × 10 7 BMCs, and fibroblasts were transplanted into a 15 mm long chamber of the silicone tube. BMC group: About 1 × 10 7 BMCs were injected into the lumen of each tube with a vascular pedicle using a micro syringe injection. BMCs of male origin were transplanted into a tube in the sciatic nerve in male rats for electrophysiological, histological and morphological studies. Male BMCs were transplanted into vessel-containing tubes in the sciatic nerves of female rats for genomic analysis using PCR or in situ hybridization. FIB group: About 1 × 10 7 skin fibroblasts were injected into the lumen of each tube with vascular pedicle insertion. Male BMCs were transplanted into the vascularized tubes of female rats for genomic analysis using PCR. VCT group: No cells were injected into the vessel-containing tube. At 12 and 24 week after transplantation, electrophysiological and morphological examinations were performed on each rat. Schwann cells derived from the BMCs inserted into the vessel-containing tube were quantified genetically using a polymerase chain reaction (PCR) specific to the sex-determining region of the Y-chromosome, Sry. To confirm the differentiation of the BMCs into Schwann cell-like phenotypes, the fluorescent in situ hybridization study with the paint-probe for Y-chromosome was performed on the adjacent slice to the one on which the immunohistochemical-staining study specific to the S-100 and GFAP proteins was performed. RESULTS SECTION: Electrophysiological studies were performed at 12 and 24 weeks. At 12 weeks, the action potential evoked in the pedal adductor muscle of the BMC, FIB and VCT groups was observed in 9 out of 12, 2 out of 12, and 3 out of 12 specimens, respectively. The mean values of the pedal adductor muscle amplitude (%) of the BMC, FIB and VCT groups were 14.9 ± 4.6, 2.2 ± 1.3 and 3.1 ± 1.2, respectively (the statistical comparison was not done). At 24 weeks, the mean values of the pedal adductor muscle amplitude (%) of the BMC, FIB and VCT groups were 55.2 ± 6.1, 5.9 ± 5.3 and 30.1 ± 9.6, respectively. The mean amplitude of the BMC group was significantly greater than those of the FIB and VCT groups (P < 0.001). The mean amplitude of the VCT group was significantly greater than that of the FIB group (P < 0.001). Morphological studies were subsequently performed at 12 and 24 weeks. At 12 weeks, the mean total number of myelinated axons and the standard variations in the BMC, FIB and VCT groups were 12658 ± 2071, 1805 ± 696 and 5901 ± 1054, respectively. The mean value of the BMC group was significantly greater than those of the FIB and VCT groups (both P < 0.001). The mean value of the VCT group was significantly greater than that of the FIB group (P < 0.001). At 24 weeks, the mean total myelinated axon numbers and the standard variations of the three groups were 12629 ± 1818 in the BMC group, 2292 ± 1209 in the FIB group and 6476 ± 1011 in the VCT group. The 24-week mean value of the BMC group was significantly greater than those of the FIB and VCT groups (both P <0.001). The mean value of the VCT group was significantly greater than that of the FIB group (P < 0.001). At 12 weeks, the mean diameters of myelinated axons and the standard variations of the BMC, FIB and VCT groups were 0.97 ± 0.10, 0.81 ± 0.06 and 0.90 ± 0.05 µm, respectively. The mean axon diameter of the BMC group was significantly greater than that of the FIB group (P = 0.004) and the mean value of the VCT group was significantly greater than that of the FIB group (P = 0.015), but no significant difference was found between the BMC and VCT groups. At 24 weeks, the mean myelinated axon diameters and the standard variations were 1.02 ± 0.06 µm in the BMC group, 0.92 ± 0.02 µm in the FIB group and 0.93 ± 0.03 µm in the VCT group. The values of the BMC group were significantly greater than those of the FIB and VCT groups (both P < 0.001). No significant difference was found between the FIB and VCT groups. In the vessel-containing tube with transplanted BMCs, the mean ratio of Sry to β-actin in the BMC group was 0.294 ± 0.151 and 0.134 ± 0.060 in the FIB group. PCR studies revealed that about 29% of cells in the regenerated nerve originated from the BMCs. Cells identified as having BMC origin via in situ hybridization were positively stained by anti-S100 and anti-GFAP antibodies.
doi:10.3727/000000007783465226 pmid:18088001 fatcat:lzotuvsduzajpmxdd7foyw57iq

Disruption of endogenous perlecan function improves differentiation of rat articular chondrocytesin vitro

Ryosuke Nakamura, Fumio Nakamura, Shigeharu Fukunaga
2014 Animal Science Journal  
2 Heparan sulfate (HS) and heparan sulfate proteoglycans (HSPG) are 3 necessary for normal cartilage development and chondrocyte differentiation. 4 However, recent studies demonstrated that HSPG accelerate 5 dedifferentiation and catabolism in chondrocytes from degenerative cartilage. 6 In this study, we investigated the inhibitory effect of HSPG on chondrocyte 7 differentiation in vitro. Rat articular chondrocytes were cultured at low (0.3 8 × 10 4 cells/cm 2 ) and high (1.5 × 10 5 cells/cm 2
more » ... density in the presence or 9 absence of heparitinase I, an HS degrading enzyme. Cells cultured at low 10 density dedifferentiated and exhibited an elongated morphology, and 11 treatment with heparitinase I precluded cell elongation. Conversely, 12 populations of chondrocytes cultured at high density exhibited either a 13 dedifferentiated or differentiated phenotype. Glycosaminoglycan 14 accumulation increased in heparitinase I-treated cells. To determine the 15 function of perlecan, an important HSPG for cartilage development, in 16 chondrocyte differentiation, rat chondrocyte cultures were exposed to an 17 anti-perlecan antiserum to inhibit perlecan function. Western blotting 18 analysis indicated that preventing perlecan activity increased type II 19 collagen synthesis. Our results suggest that HSPG are negative regulators of 20 chondrocyte differentiation in vitro and that perlecan contributes to 21 chondrocyte dedifferentiation in vitro. 22 23
doi:10.1111/asj.12309 pmid:25410015 fatcat:czd2hvnezncqfjni63zdfaoqj4

Human Sensing in Crowd Using Laser Scanners [chapter]

Katsuyuki Nakamura, Huijing Zhao, Xiaowei Shao, Ryosuke Shibasaki
2012 Laser Scanner Technology  
Laser Scanner Technology How to reference In order to correctly reference this scholarly work, feel free to copy and paste the following: Katsuyuki Nakamura, Huijing Zhao, Xiaowei Shao and Ryosuke Shibasaki  ...  Nakamura et al. used the mean shift visual tracker to support laser-based tracking (Nakamura et al., 2005) .  ... 
doi:10.5772/33276 fatcat:ogboezs3xjamphb5rx27dinpbu

Triangular-shaped lingual osteotomy using a bone saw in sagittal split ramus osteotomy

Ryosuke Kita, Aya Yoshino, Ryosuke Mano, Shinsuke Nakamura, Seiji Kondo
2021 Advances in Oral and Maxillofacial Surgery  
doi:10.1016/j.adoms.2021.100132 fatcat:ezm7ph4vpjfsjf6ftaqybrbs4y

SOIC: Semantic Online Initialization and Calibration for LiDAR and Camera [article]

Weimin Wang, Shohei Nobuhara, Ryosuke Nakamura, Ken Sakurada
2020 arXiv   pre-print
Nakamura and K.  ... 
arXiv:2003.04260v1 fatcat:co7nubfmkrfyrou2ahuaf7dyua

Triangular-shaped lingual osteotomy using a bone saw in sagittal split ramus osteotomy

Ryosuke Kita, Aya Yoshino, Ryosuke Mano, Shinsuke Nakamura, Seiji Kondo
2021 Advances in Oral and Maxillofacial Surgery  
doi:10.1016/j.adoms.2021.100133 fatcat:rzmbtdm7vffc7p6zlrsszwyo7i

Synthesis of Flavanones. VI

Shin-ichiro Fujise, Ryosuke Fujii, Toshihiro Maeda, Kunihiko Takagi, Shotaro Nakamura
1953 Nippon kagaku zassi  
doi:10.1246/nikkashi1948.74.827 fatcat:nqyrt5j33rcejlnqmispd7iruy

Scale Estimation of Monocular SfM for a Multi-modal Stereo Camera [article]

Shinya Sumikura, Ken Sakurada, Nobuo Kawaguchi, Ryosuke Nakamura
2018 arXiv   pre-print
This paper proposes a novel method of estimating the absolute scale of monocular SfM for a multi-modal stereo camera. In the fields of computer vision and robotics, scale estimation for monocular SfM has been widely investigated in order to simplify systems. This paper addresses the scale estimation problem for a stereo camera system in which two cameras capture different spectral images (e.g., RGB and FIR), whose feature points are difficult to directly match using descriptors. Furthermore,
more » ... number of matching points between FIR images can be comparatively small, owing to the low resolution and lack of thermal scene texture. To cope with these difficulties, the proposed method estimates the scale parameter using batch optimization, based on the epipolar constraint of a small number of feature correspondences between the invisible light images. The accuracy and numerical stability of the proposed method are verified by synthetic and real image experiments.
arXiv:1810.11856v1 fatcat:2bht26id6bbx5boeurumgea3fy

Fabchain: Managing Audit-able 3D Print Job over Blockchain [article]

Ryosuke Abe, Shigeya Suzuki, Kenji Saito, Hiroya Tanaka, Osamu Nakamura, Jun Murai
2022 arXiv   pre-print
Improvements in fabrication devices such as 3D printers are becoming possible for personal fabrication to freely fabricate any products. To clarify who is liable for the product, the fabricator should keep the fabrication history in an immutable and sustainably accessible manner. In this paper, we propose a new scheme, "Fabchain," that can record the fabrication history in such a manner. By utilizing a scheme that employs a blockchain as an audit-able communication channel, Fabchain manages
more » ... t jobs for the fabricator's 3D printer over the blockchain, while maintaining a history of a print job. We implemented Fabchain on Ethereum and evaluated the performance for recording a print job. Our results demonstrate that Fabchain can complete communication of a print job sequence in less than 1 minute on the Ethereum test network. We conclude that Fabchain can manage a print job in a reasonable duration for 3D printing, while satisfying the requirements for immutability and sustainability.
arXiv:2203.03119v1 fatcat:h6y4mpojjfaqxnpsh5huit46ou

Multi-band imaging camera and its sciences for the Japanese near-earth asteroid mission MUSES-C

Tsuko Nakamura, Akiko M Nakamura, Jun Saito, Sho Sasaki, Ryosuke Nakamura, Hirohide Demura, Hiroaki Akiyama, David Tholen
2001 Earth, Planets and Space  
One of the authors (T.N.) also had similar experience in comet polarimetry (Nakamura et al., 1991) .  ...  Considering that a greater impact meteoroid flux necessarily implies production of a higher cloud density and a higher chance of its detection, Nakamura (1998) proposed an in-situ exploration of dust  ... 
doi:10.1186/bf03351703 fatcat:momk4nbz4ne3hju2hrn6x7ykfq

Allergy of Hydrolyzed Wheat Protein via Cutaneous Sensitization
加水分解コムギの経皮感作によるアレルギー

Shinobu SAKAI, Rika NAKAMURA, Ryosuke NAKAMURA, Reiko ADACHI, Reiko TESHIMA
2014 KAGAKU TO SEIBUTSU  
doi:10.1271/kagakutoseibutsu.52.431 fatcat:jwgfce7ovrairjm5wys2alvcse
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