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We report the first case of sepsis with enterocolitis that was caused by a novel urease-positive Helicobacter species in a young man. The isolate was characterized via 16S rRNA gene sequencing and their biochemical properties, and the patient was successfully treated with short-term antimicrobial therapy; no recurrence was observed.  相似文献   
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Pathological diagnosis of dermal melanocytic tumors is often problematic owing to histological resemblance. Recently, cutaneous melanocytoma with CRTC1‐TRIM11 (CMCT) was added to this category. However, only six cases have been reported so far. We herein present a case of a 77‐year‐old Japanese man with CMCT. The patient presented a nodule in the right thigh and underwent surgical resection. Histological examination indicated a well‐demarcated 6 × 5 mm‐sized tumor nodule in the dermis and subcutis. The tumor was amelanotic, consisting of uniform nests and fascicles of spindled, or epithelioid cells. The melanocytic nature was evident by immunohistochemistry. The CRTC1‐TRIM11 fusion was detected by TRIM11 immunostaining, chromogenic in situ hybridization, and RT‐PCR/direct sequencing. He has been free from the tumor for 1 year after additional resection. The main differential diagnosis of CMCT includes primary and metastatic dermal malignant melanomas (MM) and dermal/subcutaneous clear cell sarcoma (CCS). Additionally, histological overlap with paraganglioma‐like dermal melanocytic tumor was considered. Although some investigators argue that CMCT is a variant of CCS, we think it should be separated from CCS, and subcutaneous/dermal CCS should be confined to tumors with EWSR1‐ATF1/ CREB1 fusion. However, longer follow‐up and more case studies are needed for revealing the true prognosis of CMCT.  相似文献   
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Hyaluronan (HA) exists in various living tissues as one of the major matrix macromolecules, and is well known to play an integral role in cell differentiation and proliferation. The present study was conducted to elucidate whether or not the proliferation of periodontal ligament (PDL) cells are affected specifically by the degradation of HA by hyaluronidasze (HAase). Human PDL fibroblasts were isolated and cultured with and without 15-150U/ml bovine testicular HAase from 1 to 11 days after seeding. The cells were also cultured with anti-CD44 antibody of 2 microg/ml. For the control against the anti-CD44 antibody treatment, 2 microg/ml IgG was used. The HA-dependent pericellular matrix was visualized by particle-exclusion assay. The number of cells was counted by MTT assay during the proliferation. The mRNA levels of HA synthases (HASs), HAases (HYALs) and CD44s were examined by a quantitative real-time PCR analysis. The cell proliferation was inhibited by the treatment with HAase and anti-CD44 antibody in cultured PDL fibroblasts. HASs mRNAs were down-regulated, whereas HYALs mRNAs were up-regulated significantly by the treatment with HAase and anti-CD44 antibody. The CD44s mRNA level exhibited no significant changes. These results suggest that HA may contribute to modulate the proliferation of cultured human PDL cells through a CD44-mediated mechanism.  相似文献   
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We have previously synthesized a novel acrylic resin monomer, methacryloyloxyethyl methyl succinate (TA). The aim of this in vitro study, therefore, was to examine its influence on cell viability using L-929 mouse fibroblasts and then compare the results with MMA, EMA, and LMA. Medium containing each monomer was changed every 15 minutes as some monomers were volatile. After one hour of exposure, these mediums were replaced with a normal medium and cells were further incubated for 72 hours. IC50 value for each monomer was determined, and chronological cell viability and cytomorphologic observation were evaluated. Viability was impaired in a dose-dependent manner. All monomers, except TA, tended to correlate between molecular weight and cell viability. On the other hand, TA showed excellent viability and did not impair growth abruptly. These results thus demonstrated that cellular damage by TA was much lower than that by other monomers.  相似文献   
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A morphometric analysis system of digital radiographic images was constructed for the clinical evaluation of bone trabecular structural change. This system consisted of computed radiography, a mathematical morphological filter, skeletal morphometric measurements, star volume analysis, and node-strut analysis. The computed radiographic data were morphologically processed, and the trabecular structure was extracted as binary skeletal images. Analyses were made with regard to the skeletal number, separation, perimeter, complexity, continuity, and connectivity. A trial study of this system was used to evaluate the therapeutic efficacy of vitamin K2 in the osteoporotic patients. The system enabled the quantitative evaluation of bone trabecular structural change. Significant differences were observed in the parameters of the skeletal perimeter, skeletal number, and skeletal connectivity in the femur, and improvements in the trabecular structure were indicated. In the lumbar vertebra, significant differences were observed in nearly the same parameters as the femur, although the trabecular structure had deteriorated. These results suggest that the system for bone morphometric analysis of digital radiographic images is useful for the evaluation of structural change in bone trabeculation. Source of support This work was performed at Kanagawa Dental College, Research Center of Advanced Technology for Craniomandibular Function and was supported by a grant-in-aid for Bioventure Research from the Japanese Ministry of Education, Culture, Sports, Science, and Technology.  相似文献   
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