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991.
Objective: We report two cases of atypical femoral fracture (AFF) in patients with cancer.Patients: Two patients, a 53-year-old woman with breast cancer and a 77-year-old man with prostate cancer, could not walk after being injured in a fall. They used bone-modifying agents (BMA) for the prevention of bone metastasis for three and four years, respectively.Results: Intramedullary nails were placed to fix the femoral fractures in each patient. Neither of them had pathological metastatic femoral fractures based on fracture site specimens; however, severe suppression of bone turnover at the fracture site was suspected. Both patients could ambulate with a T-cane and were free of hip pain after surgery. Radiographs showed no callus formation at the fracture site.Conclusion: Based on the two cases of AFF in patients with cancer related to BMA use, we should consider that the incidence of AFF may be associated with long-term BMA use.  相似文献   
992.
A 63-year-old man was admitted to our hospital in March 2017 with dysphagia and right homonymous hemianopsia. We diagnosed him with esophagogastric junction cancer (adenocarcinoma) with metastases to the cerebral occipital lobe, bone, and lymph nodes. After one cycle of 5FU + cisplatin (FP), the brain metastasis was resected because of the hemiplegic symptoms he developed. Histology of the resected tissue showed no viable tumor cells. After three cycles of FP, the primary lesion and metastases were resolved. Upper gastrointestinal endoscopy revealed a scar at the primary site. This was considered a complete response (CR). In April 2018, CT revealed a mass at the cardia, which was considered as lymph node metastases with gastric wall invasion. Although two additional cycles of FP were administered for recurrent tumors, the efficacy was progressive. In August 2018, proximal gastrectomy and D1 + lymph node dissection were performed. The pathological diagnosis was gastric intramural metastases and lymph node metastases (ypN1 [2/22]). Weekly paclitaxel therapy was administered for three months after surgery. Two years have passed since the last surgery without recurrence. We report a rare case of esophagogastric junction cancer with brain, bone, and gastric intramural metastases that responded to combined modality therapy.  相似文献   
993.
Epithelial injury is a central finding in pulmonary disease and is accompanied by disruption of epithelial barrier function, leading to pulmonary oedema and inflammation. Injured epithelial cells lose their properties and gain mesenchymal characteristics, a phenotypic switch that contributes to lung remodelling after injury. Here we studied bone morphogenetic protein (BMP) signalling and, in particular, the role of BMP2 and the BMP modulator BMPER in injured lung epithelium. Increased BMP activity, reflected by up‐regulation of the Smad1/5–Id1 axis, is detected after injury of lung epithelium in vitro and in vivo. Two members of the BMP family, BMP2 and BMPER, have opposing effects. BMP2 is up‐regulated after epithelial injury and causes epithelial dysfunction and hyperpermeability, mediated by the Smad1/5–Id1‐dependent down‐regulation of E‐cadherin. In contrast, BMPER expression is decreased following injury, which in turn impairs epithelial integrity, characterized by reduction of E‐cadherin and epithelial leakage in vitro and in vivo. High levels of BMPER antagonized BMP2‐Smad5–Id1 signalling and prevented BMP2‐mediated decrease of E‐cadherin and hyperpermeability, suggesting that BMPER restores epithelial homeostasis. Supporting this notion, pharmacological inhibition of BMP signalling by LDN193189 prevented reduction of E‐cadherin and disruption of epithelial barrier function. Inhibition of excessive BMP activation could be a new approach to restore epithelial integrity and prevent disruption of epithelial barrier function after lung injury. Copyright © 2013 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.  相似文献   
994.
Intradural petrous bone drilling has become a widespread practice, providing extended exposure in the removal of cerebellopontine angle (CPA) or petroclival tumors. Adjacent neurovascular structures are at risk, however, when drilling is performed in this deep and narrow area. Hence, this study evaluates the use of Piezosurgery (PS) as a non-rotating tool for selective bone cutting in CPA surgery.A Piezosurgery® device was used in 36 patients who underwent microsurgery for extra-axial CPA or petroclival tumors in our Neurosurgical Department between 2013 and 2019. The clinical and radiological data were retrospectively analyzed. The use of PS was evaluated with respect to the intraoperative applicability and limitations as well as efficacy and safety of the procedure.Piezosurgical petrous bone cutting was successfully performed in the removal of meningiomas or extra-axial metastases arising from the dura of the petroclival region (21 patients) or petrous bone (15 patients). PS proved to be very helpful in the deep and narrow CPA region, considerably reducing the surgeon’s distress toward bone removal in close proximity to cranial nerves and vessels in comparison to common rotating drills. The use of PS was safe without injuries to neurovascular structures. Gross total resection was achieved in 67% of petroclival and 100% of petrous bone tumors.Piezosurgery proved to be an effective and safe method for selective petrous bone cutting in CPA surgery avoiding rotating power and associated risks. This technique can particularly be recommended for bone cutting in close vicinity to critical neurovascular structures.  相似文献   
995.
 目的:探讨侧壁开窗法上颌窦底提升术这种特殊的引导性骨再生(guided bone regeneration, GBR)过程的转录组特点。方法:3只Beagle犬,随机选择一侧经侧壁开窗行上颌窦底提升术,同时植入Bio-Oss骨粉,术后2周,对另一侧用相同的方法行上颌窦底提升术。第2次术后2周,收集植入的Bio-Oss骨粉组织块,提取总RNA,全基因组表达谱芯片检测分析上颌窦底提升后2周和4周时的差异表达基因。利用基因本体论(gene ontology, GO)对差异表达的基因进行功能分类,以及京都基因与基因组百科全书(Kyoto Encyclopedia of Genes and Genomes, KEGG)进行信号通路分析。结果:在2周时表达升高的基因与刺激反应、免疫-炎症反应和细胞增殖有关,同时,与神经元分化、破骨细胞分化和早期血管化过程相关的基因也高表达。在4周时,与细胞代谢和发育相关的基因表达升高,重要的是,与血管生成和骨骼发育相关的基因都高表达,与骨骼发育相关的基因包括骨生成相关的生长和分化因子[转化生成因子β1(transforming growth factor beta 1, TGFB1)和骨形态发生蛋白4(bone morphogenetic protein 4, BMP4)]、软骨和骨胞外基质[软骨黏附素(chondroadherin, CHAD)、Ⅰ型胶原α1链(collagen type I, alpha 1 chain, COL1A1)、Ⅰ型胶原α2链(collagen type I, alpha 2 chain, COL1A2)、Ⅴ型胶原α2链(collagen type Ⅴ, alpha 2 chain, COL5A2)、核心蛋白聚糖(decorin, DCN)、骨连接蛋白(osteonectin, SPARC)和骨钙素(osteocalcin, BGLAP)]等相关的基因。信号通路分析显示4周时表达升高的基因与转化生长因子β/骨形态发生蛋白(transforming growth factor beta/bone morphogenetic protein, TGF-β/BMP)信号通路有关。无翅型MMTV整合位点家族(wingless-type MMTV integration site family, WNT)信号通路中的关键基因WNT5A和卷曲蛋白受体9(frizzled receptor 9, FZD9)在2周时表达升高,而连环蛋白β1(catenin beta 1, CTNNB1)在4周时表达升高。结论:侧壁开窗法上颌窦底提升术2周后转录表达谱变化以免疫-炎症反应和破骨反应下调、骨生成相关基因表达升高为特点,骨再生的过程还与神经生成和血管生成过程相关。在骨再生的过程中,TGF-β/BMP和WNT信号通路起重要作用,WNT信号通路的作用复杂。  相似文献   
996.
997.
998.
Background and PurposeWe investigated 18F-fluorodeoxyglucose (FDG) uptake levels in the lumbar vertebrae, liver, and spleen of stroke patients with carotid atherosclerosis.MethodsThis study analyzed acute ischemic stroke patients with carotid atherosclerosis who underwent whole-body FDG positron-emission tomography between October 2015 and January 2017. FDG uptake in the lumbar vertebrae, liver, and spleen was measured and compared between stroke patients and control subjects without stroke history. Multivariate linear regression analysis was performed to identify independent factors related to FDG uptake in the proximal internal carotid artery (ICA).ResultsTwenty stroke patients aged 75.1±9.0 years (mean±standard deviation; 10 females) and 20 control subjects aged 62.9±10.7 years (6 females) were included. In comparison with the control group, the stroke group showed significantly higher FDG uptake in the proximal ICA (1.16±0.26 vs. 0.87±0.19, p<0.01), but significantly lower FDG uptake in the lumbar vertebrae (1.09±0.26 vs. 1.38±0.38, p=0.007) and liver (1.71±0.30 vs. 2.01±0.34, p=0.005). Multivariate linear regression analysis showed that the lumbar FDG uptake was negatively correlated with FDG uptake in the proximal ICA (standardized coefficient=-0.367, p=0.013) after adjusting for age and hypertension.ConclusionsStroke patients showed decreased FDG uptake in the lumbar vertebrae. Further studies are warranted to evaluate the pathophysiological link between cerebral atherosclerosis and bone.  相似文献   
999.
1000.
The distal papilla around tooth-bound implant-supported restorations in maxillary central incisor sites tends to exhibit an atrophied aspect after tissue maturation following the delivery of the final prosthesis. This article provides an explanation to this phenomenon, as well as a set of therapeutic considerations to minimize its occurrence and optimize the outcomes of tooth replacement therapy with dental implants in this specific anatomic location.  相似文献   
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