540 research outputs found

    A Review of Literature on Platform Business and Business Model <Notes>

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    支配力を有するプラットフォームが既に存在する市場において,後発の製品・サービスが事業性を構築し,持続するにはどのようなメカニズムが存在するのかを調査するための分析視角をプラットフォームとビジネスモデルの文献をレビューし検討した。プラットフォーム研究の競争戦略的な視角とビジネスモデル研究の「儲ける仕組み」「提供する価値と価値を届ける仕組みや構造」を示す分析視角を組み合わせることで,プラットフォーム・ビジネスの事業性の構築と持続につながる筋道をより深く理解できると考える

    Formation of hexagonal and cubic fluorescent periodic mesoporous organosilicas in the channels of anodic alumina membranes

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    The synthesis of periodic mesoporous organosilicas (PMOs) in the confinement of porous anodic alumina membranes (AAMs) was successfully achieved through a modified evaporation-induced self-assembly (EISA) process. 1,3,5-Tris(4-triethoxysilylstyryl)benzene, (a three-armed oligo(phenylenevinylene) organosilane compound, abbr. 3a-OPV), the precursor of the first reported charge-conducting PMO, was used as an organosilica source. Triblock-copolymers Pluronic F127 (EO106 PO70 EO106) or F108 (EO132 PO50 EO132) were used as structure directing agents. The block-copolymer F127 led to a 2D-hexagonal circular mesostructure within the AAM channels and the block copolymer Pluronic F108 resulted in a mesophase with a body-centered cubic (Im3 with combining macronm) structure. Compared to the previously reported 3a-OPV-PMO film{,} the resulting hierarchical PMO/AAM systems have improved features{,} that is{,} the synthesized PMOs have a pore size of around 10 nm and the compounds are found to be stable against thermal treatment at temperatures of up to 200 degreeC and they are also stable in the electron beam of the electron microscope. Additionally{,} both of the resulting hierarchical mesoporous composites show fluorescence in the visible region due to the strongly interacting phenylenevinylene chromophores in the PMO frameworks

    Computer simulation of bistable switching in a nematic device containing pear-shaped particles

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    We study the microscopic basis of bistable switching of a confined liquid crystal via Monte Carlo simulations of hard pear-shaped particles. Using both dielectric and dipolar field couplings to this intrinsically flexoelectric fluid, it is shown that pulsed fields of opposing polarity can be used to switch between the vertical and hybrid aligned states. Further, it is shown that the field-susceptibility of the surface polarisation, rather than the bulk flexoelectricity, is the main driver of this switching behaviour.</p

    Involvement of oxidative stress and mucosal addressin cell adhesion molecule-1 (MAdCAM-1) in inflammatory bowel disease

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    The pathophysiology of inflammatory bowel disease involves excessive immune effects of inflammatory cells against gut microbes. In genetically predisposed individuals, these effects are considered to contribute to the initiation and perpetuation of mucosal injury. Oxidative stress is a fundamental tissue-destructive mechanisms that can occur due to the reactive oxygen species and reactive nitrogen metabolites which are released in abundance from numerous inflammatory cells that have extravasated from lymphatics and blood vessels to the lamina propria. This extravasation is mediated by interactions between adhesion molecules including mucosal addressin cell adhesion molecule-1 and vascular cell adhesion molecule-1 on the surface of lymphocytes or neutrophils and their ligands on endothelial cells. Thus, reactive oxygen species and adhesion molecules play an important role in the development of inflammatory bowel disease. The present review focuses on the involvement of oxidative stress and adhesion molecules, in particular mucosal addressin cell adhesion molecule-1, in inflammatory bowel disease

    Changes in 12-Year First-Line Eradication Rate of Helicobacter pylori Based on Triple Therapy with Proton Pump Inhibitor, Amoxicillin and Clarithromycin

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    A triple therapy based on a proton pump inhibitor (PPI), amoxicillin (AMPC), and clarithromycin (CAM) is recommended as a first-line therapy for Helicobacter pylori (H. pylori) eradication and is widely used in Japan. However, a decline in eradication rate associated with an increase in prevalence of CAM resistance is viewed as a problem. We investigated CAM resistance and eradication rates over time retrospectively in 750 patients who had undergone the triple therapy as first-line eradication therapy at Nagoya City University Hospital from 1995 to 2008, divided into four terms (Term 1: 1997–2000, Term 2: 2001–2003, Term 3: 2004–2006, Term 4: 2007–2008). Primary resistance to CAM rose significantly over time from 8.7% to 23.5%, 26.7% and 34.5% while the eradication rate decreased significantly from 90.6% to 80.2%, 76.0% and 74.8%. Based on the PPI type, significant declines in eradication rates were observed with omeprazole or lansoprazole, but not with rabeprazole. A decrease in the H. pylori eradication rate after triple therapy using a PPI + AMPC + CAM has been acknowledged, and an increase in CAM resistance is considered to be a factor. From now on, a first-line eradication regimen that results in a higher eradication rate ought to be investigated

    Nuclear translocation of the cytoplasmic domain of HB-EGF induces gastric cancer invasion

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    BACKGROUND: Membrane-anchored heparin-binding epidermal growth factor-like growth factor (proHB-EGF) yields soluble HB-EGF, which is an epidermal growth factor receptor (EGFR) ligand, and a carboxy-terminal fragment of HB-EGF (HB-EGF-CTF) after ectodomain shedding. We previously reported that HB-EGF-CTF and unshed proHB-EGF which has the cytoplasmic domain of proHB-EGF (HB-EGF-C), translocate from the plasma membrane to the nucleus and regulate cell cycle after shedding stimuli. However, the significance of nuclear exported HB-EGF-C in human gastric cancer is unclear. METHODS: We investigated the relationship between intracellular localization of HB-EGF-C and clinical outcome in 96 gastric cancer patients treated with gastrectomy. Moreover, we established stable gastric cancer cell lines overexpressing wild-type HB-EGF (wt-HB-EGF) and mutated HB-EGF (HB-EGF-mC), which prevented HB-EGF-C nuclear translocation after shedding. Cell motility between these 2 gastric cancer cell lines was investigated using a transwell invasion assay and a wound healing assay. RESULTS: Of the 96 gastric cancer cases, HB-EGF-C immunoreactivity was detected in both the nucleus and cytoplasm in 19 cases (19.8 %) and in the cytoplasm only in 25 cases (26.0 %). The nuclear immunoreactivity of HB-EGF-C was significantly increased in stage pT3/4 tumors compared with pT1/2 tumors (T1/2 vs. T3/4: 11.1 % vs. 36.4 %, P < 0.01). The growth of wt-HB-EGF- and HB-EGF-mC-expressing cells significantly increased compared with control cells, but the growth of HB-EGF-mC-expressing cells was significantly decreased compared with wt-HB-EGF-expressing cells. Gastric cancer cell invasion obviously increased in wt-HB-EGF-expressing cells, but invasion in HB-EGF-mC-expressing cells showed a slight increase compared with control cells. Moreover, wt-HB-EGF overexpression increased the effectiveness of wound healing, but had no significant effect in HB-EGF-mC-expressing cells. CONCLUSIONS: Both the function of HB-EGF as an EGFR ligand and a novel signal for HB-EGF-C nuclear translocation induce gastric cancer growth, whereas HB-EGF-C nuclear translocation independently plays a critical role in gastric cancer invasion. The present study demonstrated that HB-EGF-C nuclear translocation might be crucial in gastric cancer invasion. HB-EGF-C nuclear translocation may offer a prognostic marker and a new molecular target for gastric cancer therapy

    A Complicated Case of Tacrolimus-Induced Rapid Remission after Cesarean Section in the Early Third Trimester for Refractory Severe Ulcerative Colitis Flaring in the Initial Period of Gestation

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    A 36-year-old woman who had been diagnosed with ulcerative colitis at the age of 17 years was referred to our hospital because of severe abdominal pain and repeated bloody diarrhea that persisted during pregnancy despite combination therapy with high-dose corticosteroids and weekly granulocyte and monocyte adsorptive apheresis (GMA). She underwent combination therapy consisting of high-dose corticosteroids, intensive GMA (two sessions per week) and vancomycin, which was used to eradicate Clostridium difficile, under total parenteral nutrition control until the estimated weight of her fetus reached 1,000 g. This combination therapy was partially successful, resulting in almost complete disappearance of abdominal pain and a marked decrease in stool frequency. However bloody diarrhea persisted and the patient developed anemia and hypoalbuminemia and was unable to prolong her gestation time. Cesarean section was conducted at 28 weeks of gestation without any congenital abnormalities or neurological defects. Oral administration of tacrolimus was begun 7 days after cesarean section, which was followed by rapid induction of remission. Corticosteroids were then gradually tapered off. Tacrolimus is one therapeutic option after cesarean section in pregnant patients who do not respond well to GMA and high-dose corticosteroids for persistent active ulcerative colitis

    CDX1 and CDX2 Expression in Intestinal Metaplasia, Dysplasia and Gastric Cancer

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    Intestinal metaplasia (IM) has been regarded as a premalignant condition. However, the pathogenesis of IM is not fully understood. The aim of this study was to evaluate the role of CDX1 and CDX2 in the formation of IM and the progression to dysplasia and gastric cancer (GC). A total of 270 subjects included 90 with GC, dysplasia and age- and sex-matched controls. Real-time PCR (RT-PCR) was performed with body specimens for CDX1 and CDX2. The expression of CDX2 was significantly higher in H. pylori positive group than H. pylori negative group (P = 0.045). CDX1 and CDX2 expression increased proportional to the IM grade of the body (P < 0.001). CDX2 expression was significantly higher in incomplete type of IM than in complete type (P = 0.045). The expression of CDX1 in dysplasia group was significantly higher than in the control group (P = 0.001); in addition, CDX1 and CDX2 in cancer group was significantly higher than control group (P < 0.001, and P < 0.001, respectively). Aberrant expression of CDX1 and CDX2 correlated with H. pylori infection and grade of IM in the body. Furthermore, the results suggest that CDX1 and CDX2 play a role in the progression to GC and dysplasia
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