254 research outputs found

    Salvage Surgery for Symptomatic Recurrence of Retro-Odontoid Pseudotumor after a C1 Laminectomy

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    We provide the first report of successful salvage surgery for a post-C1 laminectomy symptomatic recurrence of a retro-odontoid pseudotumor (ROP) that caused myelopathy. The 72-year-old Japanese woman presented with an ROP causing symptomatic cervical myelopathy. With ultrasonography support, we performed the enucleation of the ROP via a transdural approach and fusion surgery for the recurrence of the mass. At the final observation 2-year post-surgery, MRI demonstrated the mass’s regression and spinal cord decompression, and the patient’s symptoms had improved. Our strategy is an effective option for a symptomatic recurrence of ROP

    A novel symmetry in nanocarbons: pre-constant discrete principal curvature structure

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    Since the first-principles calculations in quantum chemistry precisely provide possible configurations of carbon atoms in nanocarbons, we have analyzed the geometrical structure of the possible carbon configurations and found that there exists a novel symmetry in the nanocarbons, i.e., the pre-constant discrete principal curvature (pCDPC) structure. In terms of the discrete principal curvature based on the discrete geometry for trivalent oriented graphs developed by Kotani, Naito, and Omori (Comput. Aided Geom. Design, 58\bf{58}, (2017), 24-54), we numerically investigated discrete principal curvature distribution of the nanocarbons, C60_{60}, carbon nanotubes, C120_{120} (C60_{60} dimer), and C60_{60}-polymers (peanut-shaped fullerene polymers). While the C60_{60} and nanotubes have the constant discrete principal curvature (CDPC) as we expected, it is interesting to note that the C60_{60}-polymers and C60_{60} dimer also have the almost constant discrete principal curvature, i.e., pCDPC, which is surprising. A nontrivial pCDPC structure with revolutionary symmetry is available due to discreteness, though it has been overlooked in geometry. In discrete geometry, there appears a center axisoid which is the discrete analogue of the center axis in the continuum differential geometry but has three-dimensional structure rather than a one-dimensional curve due to its discrete nature. We demonstrated that such pCDPC structure exists in nature, namely in the C60_{60}-polymers. Furthermore, since we found that there is a positive correlation between the degree of the CDPC structure and stability of the configurations for certain class of the C60_{60}-polymers, we also revealed the origin of the pCDPC structure from an aspect of materials science.Comment: 18 page

    Laser-based geometric modeling using cooperative multiple mobile robots

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    Abstract—In order to construct three-dimensional shape models of large-scale architectural structures using a laser range finder, a number of range images are taken from various viewpoints. These images are aligned using post-processing procedures such as the ICP algorithm. However, in general, before applying the ICP algorithm, these range images must be aligned roughly by a human operator in order to converge to precise positions. The present paper proposes a new modeling system using a group of multiple robots and an on-board laser range finder. Each measurement position is identified by a highly precise positioning technique called Cooperative Positioning System (CPS), which utilizes the characteristics of the multiple-robot system. Thus, the proposed system can construct 3D shapes of large-scale architectural structures without any post-processing procedure or manual registration. ICP is applied optionally for a subsequent refinement of the model. Measurement experiments in unknown and large indoor/outdoor environments are carried out successfully using the newly developed measurement system consisting of three mobile robots named CPS-V. Generating a model of Dazaifu Tenmangu, a famous cultural heritage, for its digital archive completes the paper. I

    Hip Fractures after Intramedullary Nailing Fixation for Atypical Femoral Fractures: Three Cases

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    Secondary hip fractures (SHFs) rarely occur after intramedullary nailing (IMN) fixation without femoral neck fixation for atypical femoral fractures (AFFs). We report three cases of older Japanese women who sustained SHFs presumably caused by osteoporosis and peri-implant stress concentration around the femoral neck after undergoing IMN without femoral neck fixation for AFF. All cases were fixed with malalignment. In AFF patients, postoperative changes due to postoperative femoral bone malalignment may affect the peri-implant mechanical environment around the femoral neck, which can result in insufficiency fractures. At the first AFF surgery, we recommend femoral neck fixation after adequate reduction is achieved

    Population genetic structure ofYamato-sllijimi clam in Lake Sbinji, Japan

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    Yamato-shijimiclam Corbicula japonica is the best-known bivalve inhabiting ln brackish estuaries and lakes around Japan and one of the most commercially important species in inland fisheries. Althoughthe amotmt of C japonica from Lake Shinji has accotmted for the large part of the domestic catch, itsamolmt has dramatically fallen in recent years・ This study was conducted to verifythe genetic structtue and reproduction mechanism of C・ japonica, both of which are essential to its stock management in Lake Shinji. Weanalyzed sequence polymorphism of the 588 bp portion ofthemitochondrial DNA cytochrome oxidase subunit I (Col) gene to determinethe population genetic structure of C・ japonica in Lake Shinji・Among a total of 177 C・ japonica specimens collected from 4 colonies, 37 haplotypes were obtained, and 2 major haplotypes were apparent withrelatively highabtmdance in all colonies・ Well correspondingmismatch distributions along the Col gene were determined for the data sets of the individual colonies, and the pairwise population estimates FsT among the individual colonies were also generally low, Such small genetic differentiation of C japonica is derived kom highgeneflow in Lake Shinji, and this could be caused by a lake-wide dispersion of its larvae mediated by the water movements・Article信州大学山地水環境教育研究センター研究報告 6: 115-124(2010)departmental bulletin pape

    Minocycline inhibits PDGF-BB-induced human aortic smooth muscle cell proliferation and migration by reversing miR-221- and -222-mediated RECK suppression

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    Minocycline, a tetracycline antibiotic, is known to exert vasculoprotective effects independent of its anti-bacterial properties; however the underlying molecular mechanisms are not completely understood. Reversion Inducing Cysteine Rich Protein with Kazal Motifs (RECK) is a cell surface expressed, membrane anchored protein, and its overexpression inhibits cancer cell migration. We hypothesized that minocycline inhibits platelet-derived growth factor (PDGF)-induced human aortic smooth muscle cell (SMC) proliferation and migration via RECK upregulation. Our data show that the BB homodimer of recombinant PDGF (PDGF-BB) induced SMC migration and proliferation, effects significantly blunted by pre-treatment with minocycline. Further investigations revealed that PDGF-BB induced PI3K-dependent AKT activation, ERK activation, reactive oxygen species generation, Nuclear Factor-κB and Activator Protein-1 activation, microRNA (miR)-221 and miR-222 induction, RECK suppression, and matrix metalloproteinase (MMP2 and 9) activation, effects that were reversed by minocycline. Notably, minocycline induced RECK expression dose-dependently within the therapeutic dose of 1–100 μM, and silencing RECK partially reversed the inhibitory effects of minocycline on PDGF-BB-induced MMP activation, and SMC proliferation and migration. Further, targeting MMP2 and MMP9 blunted PDGF-BB-induced SMC migration. Together, these results demonstrate that minocycline inhibits PDGF-BB-induced SMC proliferation and migration by restoring RECK, an MMP inhibitor. These results indicate that the induction of RECK is one of the mechanisms by which minocycline exerts vasculoprotective effects

    Minocycline inhibits PDGF-BB-induced human aortic smooth muscle cell proliferation and migration by reversing miR-221- and -222-mediated RECK suppression

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    Minocycline, a tetracycline antibiotic, is known to exert vasculoprotective effects independent of its anti-bacterial properties; however the underlying molecular mechanisms are not completely understood. Reversion Inducing Cysteine Rich Protein with Kazal Motifs (RECK) is a cell surface expressed, membrane anchored protein, and its overexpression inhibits cancer cell migration. We hypothesized that minocycline inhibits platelet-derived growth factor (PDGF)-induced human aortic smooth muscle cell (SMC) proliferation and migration via RECK upregulation. Our data show that the BB homodimer of recombinant PDGF (PDGF-BB) induced SMC migration and proliferation, effects significantly blunted by pre-treatment with minocycline. Further investigations revealed that PDGF-BB induced PI3K-dependent AKT activation, ERK activation, reactive oxygen species generation, Nuclear Factor-κB and Activator Protein-1 activation, microRNA (miR)-221 and miR-222 induction, RECK suppression, and matrix metalloproteinase (MMP2 and 9) activation, effects that were reversed by minocycline. Notably, minocycline induced RECK expression dose-dependently within the therapeutic dose of 1–100 μM, and silencing RECK partially reversed the inhibitory effects of minocycline on PDGF-BB-induced MMP activation, and SMC proliferation and migration. Further, targeting MMP2 and MMP9 blunted PDGF-BB-induced SMC migration. Together, these results demonstrate that minocycline inhibits PDGF-BB-induced SMC proliferation and migration by restoring RECK, an MMP inhibitor. These results indicate that the induction of RECK is one of the mechanisms by which minocycline exerts vasculoprotective effects

    人工膝関節置換術後の関節周囲感染が疑われる症例の発生頻度は、術中麻酔維持使用薬剤の選択と関連するか(プロポフォールによる全静脈麻酔と、セボフルランでの麻酔維持での比較):後ろ向きコホート研究

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    PURPOSE: Periprosthetic joint infection is a serious complication of total knee arthroplasty. Though there are many factors that might increase its risk, the use of propofol for maintaining general anesthesia could theoretically increase the incidence of infection because of its lipid component that supports bacterial growth. Nevertheless, the relationship between anesthetic maintenance agents and the occurrence of periprosthetic joint infection remains uncertain. The purpose of this study was to compare the incidence of suspected early-onset periprosthetic joint infection between patients undergoing total knee arthroplasty under propofol vs sevoflurane anesthesia. METHODS: We conducted a retrospective cohort study of patients in the national inpatient Diagnosis Procedure Combination database in Japan who underwent total knee arthroplasty. Suspected periprosthetic joint infection was surrogately defined as the need for arthrocentesis or debridement within 30 days of surgery. Propensity score matching was performed between patients who received either propofol or sevoflurane for anesthetic maintenance to determine the proportion of those with infection. RESULTS: Eligible patients (n = 21,899) were categorized into either the propofol (n = 7,439) or sevoflurane (n = 14,460) groups. In the 5,140 propensity-matched patient pairs, there was no significant difference in the proportion of arthrocentesis or debridement [1.3% propofol vs 1.7% sevoflurane; respectively (relative risk, 0.76; 95% CI, 0.55 to 1.04; P = 0.10)] between the groups. The mean (SD) length of stay in the propofol group was significantly longer than in the sevoflurane group [32.5 (18.4) days vs 31.4 (14.4) days, respectively; mean difference, 1.1; 95% CI, 0.5 to 1.8; P < 0.001]. CONCLUSION: Propensity score analysis suggested no significant association between the choice of anesthetic maintenance agent and the occurrence of suspected early-onset periprosthetic joint infection in patients undergoing total knee arthroplasty.博士(医学)・甲第700号・平成31年3月15日© Canadian Anesthesiologists' Society 2018This is a post-peer-review, pre-copyedit version of an article published in Canadian journal of anaesthesia. The final authenticated version is available online at: http://dx.doi.org/10.1007/s12630-018-1139-6

    Usefulness of Non-Uniform Heating and Quenching Method for Residual Stress of Bimetallic Roll: FEM Simulation Considering Creep Behavior

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    Bimetallic rolls are widely used in steel rolling industries because of the excellent hardness, wear resistance and high temperature properties. Controlling the residual stress distribution is important to improve the roll fatigue life due to the compressive residual stress at the roll surface. Recently, to reduce the tensile residual stress appearing at the roll center, quenching heat treatment is performed just after heating the roll non-uniformly instead of heating the roll uniformly with enough time. In this paper, therefore, the residual stresses are compared after between the uniform heating quenching and the non-uniform heating quenching on the basis of the FEM simulation. The results show that tensile stresses at the roll center for non-uniform heating are smaller than that for uniform heating by 400MPa although the same compressive stresses appear at the surface. The effect of creep on stress relaxation is also considered in this study. By considering creep, the maximum tensile residual stress decreases by 8% for uniform heating and by 15% for non-uniform heating
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