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Prognostic role of nuclear factor/IB and bone remodeling proteins in metastatic giant cell tumor of bone: A retrospective study 下载免费PDF全文
Irene Quattrini Serena Pollino Laura Pazzaglia Amalia Conti Chiara Novello Cristina Ferrari Elettra Pignotti Piero Picci Maria Serena Benassi 《Journal of orthopaedic research》2015,33(8):1205-1211
Giant cell tumor of bone (GCTb) represents 5% of bone tumors, and although considered benign, 5% metastasize to the lung. The expression of proteins directly or indirectly associated with osteolysis and tumor growth was studied on 163 samples of GCTb. Of these, 33 patients developed lung metastasis during follow‐up. The impact of tumor–host interaction on clinical aspects was evaluated with the aim of finding specific markers for new biological therapies, thus improving clinical management of GCTb. Protein expression was evaluated by immunohistochemical analysis on Tissue Microarray. The majority of GCTb samples from patients with metastatic disease were strongly positive to RANKL and its receptor RANK as well as to CAII and MMP‐2 and to pro‐survival proteins NFIB and c‐Fos. Kaplan–Meier analysis indicated a significant difference in metastasis free survival curves based on protein staining. Interestingly, the statistical correlation established a strong association between all variables studied with a higher τ coefficient for RANK/RANKL, RANK/NFIB, and RANKL/NFIB pairs. At multivariate analysis co‐overexpression of NFIB, RANK and RANKL significantly increased the risk of metastasis with an odds ratio of 13.59 (95%CI 4.12–44.82; p < 0.0005). In conclusion, the interconnection between matrix remodeling and tumor cell activity may identify tumor–host endpoints for new biological treatments. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 33:1205–1211, 2015. 相似文献
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Engineering N-linked protein glycosylation with diverse O antigen lipopolysaccharide structures in Escherichia coli 下载免费PDF全文
Feldman MF Wacker M Hernandez M Hitchen PG Marolda CL Kowarik M Morris HR Dell A Valvano MA Aebi M 《Proceedings of the National Academy of Sciences of the United States of America》2005,102(8):3016-3021
Campylobacter jejuni has a general N-linked protein glycosylation system that can be functionally transferred to Escherichia coli. In this study, we engineered E. coli cells in a way that two different pathways, protein N-glycosylation and lipopolysaccharide (LPS) biosynthesis, converge at the step in which PglB, the key enzyme of the C. jejuni N-glycosylation system, transfers O polysaccharide from a lipid carrier (undecaprenyl pyrophosphate) to an acceptor protein. PglB was the only protein of the bacterial N-glycosylation machinery both necessary and sufficient for the transfer. The relaxed specificity of the PglB oligosaccharyltransferase toward the glycan structure was exploited to create novel N-glycan structures containing two distinct E. coli or Pseudomonas aeruginosa O antigens. PglB-mediated transfer of polysaccharides might be valuable for in vivo production of O polysaccharides-protein conjugates for use as antibacterial vaccines. 相似文献
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Francine M Ducharme Sharon D Dell Dhenuka Radhakrishnan Roland M Grad Wade TA Watson Connie L Yang Mitchell Zelman 《Paediatrics & child health》2015,20(7):353-361
Asthma often starts before six years of age. However, there remains uncertainty as to when and how a preschool-age child with symptoms suggestive of asthma can be diagnosed with this condition. This delays treatment and contributes to both short- and long-term morbidity. Members of the Canadian Thoracic Society Asthma Clinical Assembly partnered with the Canadian Paediatric Society to develop a joint working group with the mandate to develop a position paper on the diagnosis and management of asthma in preschoolers.In the absence of lung function tests, the diagnosis of asthma should be considered in children one to five years of age with frequent (≥8 days/month) asthma-like symptoms or recurrent (≥2) exacerbations (episodes with asthma-like signs). The diagnosis requires the objective document of signs or convincing parent-reported symptoms of airflow obstruction (improvement in these signs or symptoms with asthma therapy), and no clinical suspicion of an alternative diagnosis. The characteristic feature of airflow obstruction is wheezing, commonly accompanied by difficulty breathing and cough. Reversibility with asthma medications is defined as direct observation of improvement with short-acting ß2-agonists (SABA) (with or without oral corticosteroids) by a trained health care practitioner during an acute exacerbation (preferred method). However, in children with no wheezing (or other signs of airflow obstruction) on presentation, reversibility may be determined by convincing parental report of a symptomatic response to a three-month therapeutic trial of a medium dose of inhaled corticosteroids with as-needed SABA (alternative method), or as-needed SABA alone (weaker alternative method). The authors provide key messages regarding in whom to consider the diagnosis, terms to be abandoned, when to refer to an asthma specialist and the initial management strategy. Finally, dissemination plans and priority areas for research are identified. 相似文献
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Gliddon et al. conducted a randomized, double-blind, multicenter, placebo-controlled study to evaluate the efficacy of the angiotensin-converting enzyme inhibitor quinapril for the management of vascular damage in systemic sclerosis (SSc). The trial comprised 213 patients with limited cutaneous SSc or Raynaud's phenomenon (mean age 54 years, 182 females) who were randomly assigned to receive 80 mg/day, or the maximum tolerated dose, of quinapril (n = 105) or placebo (n = 108) for 2-3 years. Patients were assessed every 3 months. The number of new ischemic digital ulcers was recorded as the primary end point, while the frequency of Raynaud's phenomenon episodes, skin score, health status, pulmonary artery pressure and treatments for ischemia were also monitored as secondary end points. There were no detectable differences between patients treated with quinapril and those receiving placebo; however, although no severe adverse effects were observed, patients taking quinapril experienced significantly more adverse effects. 相似文献
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Hypothalamitis: a diagnostic and therapeutic challenge 总被引:1,自引:0,他引:1
Antonio?BianchiEmail author Marilda?Mormando Francesco?Doglietto Linda?Tartaglione Serena?Piacentini Libero?Lauriola Giulio?Maira Laura?De Marinis 《Pituitary》2014,17(3):197-202
To report an unusual case of biopsy-proven autoimmune hypophysitis with predominant hypothalamic involvement associated with empty sella, panhypopituitarism, visual disturbances and antipituitary antibodies positivity. We present the history, physical findings, hormonal assay results, imaging, surgical findings and pathology at presentation, together with a 2-year follow-up. A literature review on the hypothalamic involvement of autoimmune hypophysitis with empty sella was performed. A 48-year-old woman presented with polyuria, polydipsia, asthenia, diarrhea and vomiting. The magnetic resonance imaging (MRI) revealed a clear suprasellar (hypothalamic) mass, while the pituitary gland appeared atrophic. Hormonal testing showed panhypopituitarism and hyperprolactinemia; visual field examination was normal. Pituitary serum antibodies were positive. Two months later an MRI documented a mild increase of the lesion. The patient underwent biopsy of the lesion via a transsphenoidal approach. Histological diagnosis was lymphocytic “hypothalamitis”. Despite 6 months of corticosteroid therapy, the patient developed bitemporal hemianopia and blurred vision, without radiological evidence of chiasm compression, suggesting autoimmune optic neuritis with uveitis. Immunosuppressive treatment with azathioprine was then instituted. Two months later, an MRI documented a striking reduction of the hypothalamic lesion and visual field examination showed a significant improvement. The lesion is stable at the 2-year follow-up. For the first time we demonstrated that “hypothalamitis” might be the possible evolution of an autoimmune hypophysitis, resulting in pituitary atrophy, secondary empty sella and panhypopituitarism. Although steroid treatment is advisable as a first line therapy, immunosuppressive therapy with azathioprine might be necessary to achieve disease control. 相似文献