224 research outputs found

    Composite material design of two-dimensional structures using the homogenization design method

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    Composite materials of two-dimensional structures are designed using the homogenization design method. The composite material is made of two or three different material phases. Designing the composite material consists of finding a distribution of material phases that minimizes the mean compliance of the macrostructure subject to volume fraction constraints of the constituent phases, within a unit cell of periodic microstructures. At the start of the computational solution, the material distribution of the microstructure is represented as a pure mixture of the constituent phases. As the iteration procedure unfolds, the component phases separate themselves out to form distinctive interfaces. The effective material properties of the artificially mixed materials are defined by the interpolation of the constituents. The optimization problem is solved using the sequential linear programming method. Both the macrostructure and the microstructures are analysed using the finite element method in each iteration step. Several examples of optimal topology design of composite material are presented to demonstrate the validity of the present numerical algorithm. Copyright © 2001 John Wiley & Sons, Ltd.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/34534/1/105_ftp.pd

    Effects of Gram-negative Rod Blood Stream Infection on Acute GVHD in Allogeneic Hematopoietic Stem Cell Transplantation: A Single-institute Analysis

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    A bloodstream infection (BSI) is the most common serious infectious complication of hematopoietic stem cell transplantation (HSCT). BSI promotes an inflammatory state, which exacerbates acute graft-versus-host disease (GVHD). We investigated whether a Gram-negative rod bloodstream infection (GNR-BSI), which develops early after allo-HSCT, affected the onset or exacerbated acute GVHD in 465 patients who underwent allo-HSCT from 1995 through 2015 at a single institution. Eighty-eight patients (19%) developed BSI during the study period. Among the cultures, 50 (57%) were Gram-positive cocci (GPC) and 31 (35%) were GNR. Of the 465 patients, 187 (40%) developed acute GVHD of grade II or higher within the first 100 days post-allogeneic HSCT: 124 (27%) had acute GVHD grade II, 47 (10%) had grade III, and 16 (3%) had grade IV. Multivariate analysis revealed that GNR-BSI was a significant risk factor for grade II-IV acute GVHD (grade II-IV: hazard ratio [HR] 1.75, 95% confidence interval [CI] 1.03-2.97; grade III-IV: HR 2.37, 95% CI 1.03-5.43). These results suggest that GNR-BSI may predict the onset and exacerbation of acute GVHD

    Tri-condylar形状人工膝関節において後方剥離手技が完全伸展獲得におよぼす影響:新鮮凍結屍体を用いた生体力学的評価

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    Background/objective: The continuous improvement of knee function during deep flexion remains a challenge in total knee arthroplasty. Tri-condylar total knee arthroplasty has been designed to achieve this goal. However, the introduction of a third nonanatomic spherical condyle might prevent the joint from reaching full extension due to posterior soft tissue tightening. This study aimed to address these issues related to soft tissue tightening and full extension limitation. Methods: Biomechanical tests were performed on six cadaveric specimens of the entire lower extremities. The tri-condylar design was compared with a posterior cruciate sacrificing design of the same shape without the ball structure. Knee joint kinematics was measured, including the extension and flexion angles, the extension balance, and the extension gap. The test was repeated after release of the medial and lateral posterior intercondylar soft tissues at a safe distance from the popliteal artery and nerves. Results: Both designs resulted in a knee flexion angle up to ∼130°. The tri-condylar design showed an extension angle of -11.2 ± 5.4°, which was a significantly greater limitation than that obtained with the cruciate sacrificing design (-3.8 ± 4.7°; p = 0.047). Moreover, the extension angle of the tri-condylar design was significantly improved after the release of posterior intercondylar soft tissues (-0.1 ± 6.7°; p = 0.028). Conclusion: The tri-condylar design efficiently allowed the full extension by the release of posterior intercondylar soft tissues at a safe distance from the popliteal artery and nerves.博士(医学)・乙第1499号・令和3年3月15日© 2017 The Authors. Published by Elsevier (Singapore) Pte Ltd on behalf of Chinese Speaking Orthopaedic Society. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/)

    Analysis of Immunity against Measles, Mumps, Rubella, and Varicella Zoster in Adult Recipients of Allogeneic Hematopoietic Stem Cell Transplantation: A Single-Center Experience

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    Vaccine-preventable disease (VPD) infections are more severe in immunocompromised hosts. Vaccination against measles, mumps, rubella, and varicella zoster (VZV) (MMRV) is therefore recommended for hematopoietic stem cell transplantation (HCT) recipients. However, studies on adult HCT recipients with VPD infections are limited. At our institution, we have systematically conducted serological MMRV tests as a part of check-up examinations during long-term follow-up (LTFU) after HCT since 2015. This retrospective study aimed to evaluate changes in the serostatus between before and 2 years after allogeneic HCT. Among 161 patients, the pre-transplant seropositivity was 82.7% for measles, 86.8% for mumps, 84.2% for rubella, and 94.3% for VZV. Among 56 patients who underwent LTFU including serological MMRV tests at 2 years after HCT, the percentages maintaining seroprotective antibody levels for measles, mumps, rubella and VZV were 71.5% (40/56), 51.8% (29/56), 48.2% (27/56), and 60.7% (34/56), respectively. Vaccination was recommended for 22 patients, and 12 were vaccinated. Among the 12 vaccinated patients, rates of seroconversion were examined in 2-6 patients for each of the four viruses. They were 100% (3/3) for measles, 33.3% (1/3) for mumps, 50% (3/6) for rubella, and 0% (0/2) for VZV. Further studies are warranted to clarify the effect of vaccination in adult HCT recipients

    子宮筋層の内外層に発生する子宮腺筋症おける、それぞれの組織学的特徴

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    OBJECTIVE: To estimate the phenotypic characterization of fibrotic process in adenomyosis occurring at the inner or the outer myometrium. METHODS: Eight cases of adenomyosis occurring at the inner myometrium (Subtype I) and 10 cases of adenomyosis occurring at the outer myometrium (Subtype II), and 10 normal counterparts were used in this study. A immunohistochemical study for smooth muscle cells (SMCs) was performed using cytoskeletal proteins, Type I and III collagen, TGF-β and its signaling molecules. RESULTS: An increased expression of Type I collagen was observed in the extracellular matrix of adenomyotic foci. In normal uteri, immunostaining of SMC differentiation marker proteins (Desmin, Smoothelin, Myosin heavy chain (MHC)) were absent or only found in low numbers at the inner myometrium, while all of these marker proteins were clearly stained at the outer myometrium. In both types of adenomyotic foci, Desmin, Smoothelin, and MHC commonly showed a negative staining at the adjacent area to the glands. A significant staining of Non-muscle myosin IIB, TGF-β, and phosphorylated TGF-β type I receptors were found only at the SMCs of Subtype II adenomyosis. The Smad3/2 ratio of Subtype II adenomyosis was significantly higher than that of Subtype I. CONCLUSIONS: The inner myometrium of normal uteri was composed of undifferentiated phenotypes of SMCs, while the outer myometrium was composed of terminally differentiated SMCs. Various fibrotic processes have been suggested in the development of uterine adenomyosis. Distinct expression patterns of fibrosis related proteins have been shown to be implicated with differences in the subtypes of adenomyosis.博士(医学)・甲第681号・平成30年3月15日Copyright: © 2017 Kishi et al. This is an open access article distributed under the terms of the Creative Commons Attribution License(http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited

    Combination of reduced post-transplant cyclophosphamide and early tacrolimus initiation increases the incidence of chronic graft-versus-host disease in human leukocyte antigen-haploidentical peripheral blood stem-cell transplantation

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    We evaluated the clinical impacts of the concurrent modification of post-transplant cyclophosphamide (PTCy) dose and tacrolimus (Tac)-initiation timing in 61 patients with human leukocyte antigen-haploidentical transplantation. Reduced-dose PTCy (80 mg/kg) was associated with a higher incidence of moderate-to-severe chronic graft-versus-host disease (GVHD) than standard-dose PTCy (100 mg/kg) (35.0% vs. 26.6%, p = 0.053). Notably, early-initiation Tac (day -1) increased moderate-to-severe chronic GVHD than standard-initiation Tac (day 5) in the reduced-dose PTCy group (p = 0.032), whereas Tac-initiation timing did not impact chronic GVHD in the standard-dose PTCy group. These data indicate that the combination of reduced-dose PTCy and early-initiation Tac can amplify chronic GVHD

    浸潤および血管新生を通しての人肝細胞癌の進行におけるケラチン19分子の役割

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    BACKGROUND: Keratin (K) 19-positive hepatocellular carcinoma (HCC) is well known to have a higher malignant potential than K19-negative HCC: However, the molecular mechanisms involved in K19-mediated progression of HCC remain unclear. We attempted to clarify whether K19 directly affects cell survival and invasiveness in association with cellular senescence or epithelial-mesenchymal transition (EMT) in K19-positive HCC. METHODS: K19 expression was analysed in 136 HCC surgical specimens. The relationship of K19 with clinicopathological factors and survival was analysed. Further, the effect of K19 on cell proliferation, invasion, and angiogenesis was examined by silencing K19 in the human HCC cell lines, HepG2, HuH-7, and PLC/PRF/5. Finally, we investigated HCC invasion, proliferation, and angiogenesis using K19-positive HCC specimens. RESULTS: Analysis of HCC surgical specimens revealed that K19-positive HCC exhibited higher invasiveness, metastatic potential, and poorer prognosis. In vitro experiments using the human HCC cell lines revealed that K19 silencing suppressed cell growth by inducting apoptosis or upregulating p16 and p27, resulting in cellular senescence. In addition, transfection with K19 siRNA upregulated E-cadherin gene expression, significantly inhibited the invasive capacity of the cells, downregulated angiogenesis-related molecules such as vasohibin-1 (VASH1) and fibroblast growth factor 1 (FGFR1), and upregulated vasohibin-2 (VASH2). K19-positive HCC specimens exhibited a high MIB-1 labelling index, decreased E-cadherin expression, and high microvessel density around cancer foci. CONCLUSION: K19 directly promotes cancer cell survival, invasion, and angiogenesis, resulting in HCC progression and poor clinical outcome. K19 may therefore be a novel drug target for the treatment of K19-positive HCC.博士(医学)・乙第1399号・平成29年3月15日© The Author(s). 2016 Open Access This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated

    Patient's Self-monitoring of Transurethral Surgical Images Using a Head-mounted Display

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    AbstractWe present an application of head-mounted display (HMD) to patient's self-monitoring of transurethral resection of bladder tumor (TURB). Six patients wore the HMD as an imaging monitor to view the operation in real-time during their TURB. Following the operation, the patients completed a questionnaire that evaluates understanding of the state of their disease and satisfaction with the HMD. As a result, monitoring the operation in real time through the HMD helped to increase patients' understanding of the state of their disease and satisfaction. For selected patients, the use of HMD could help to increase the patient's understanding of their disease
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