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Osric A. Forrest Daniel M. Chopyk Yael Gernez Milton R. Brown Carol K. Conrad Richard B. Moss Vin Tangpricha Limin Peng Rabindra Tirouvanziam 《Journal of cystic fibrosis》2019,18(1):64-70
Background
Resistin is an immunometabolic mediator that is elevated in several inflammatory disorders. A ligand for Toll-like receptor 4, resistin modulates the recruitment and activation of myeloid cells, notably neutrophils. Neutrophils are major drivers of cystic fibrosis (CF) lung disease, in part due to the release of human neutrophil elastase- and myeloperoxidase-rich primary granules, leading to tissue damage. Here we assessed the relationship of resistin to CF lung disease.Methods
Resistin levels were measured in plasma and sputum from three retrospective CF cohorts spanning a wide range of disease. We also assessed the ability of neutrophils to secrete resistin upon activation in vitro. Finally, we constructed a multivariate model assessing the relationship between resistin levels and lung function.Results
Plasma resistin levels were only marginally higher in CF than in healthy control subjects. By contrast, sputum resistin levels were very high in CF, reaching 50–100 fold higher levels than in plasma. Among CF patients, higher plasma resistin levels were associated with allergic bronchopulmonary aspergillosis, and higher sputum resistin levels were associated with CF-related diabetes. Mechanistically, in vitro release of neutrophil primary granules was concomitant with resistin secretion. Overall, sputum resistin levels were negatively correlated with CF lung function, independently of other variables (age, sex, and genotype).Conclusions
Our data establish relationships between resistin levels in the plasma and sputum of CF patients that correlate with disease status, and identify resistin as a novel mechanistic link between neutrophilic inflammation and lung disease in CF. 相似文献105.
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目的 探究高糖饮食对小鼠真菌性角膜炎的影响。方法 选取健康无眼疾的雄性C57BL/6J小鼠78只,随机分为高糖饮食组和模型对照组,每组36只,模型对照组给予正常饮用水,高糖饮食组给予含体积分数10%果糖溶液,每2 d测量两组小鼠体质量及血糖,10 d后建立真菌性角膜炎模型。造模后24 h、36 h、48 h、72 h、96 h、120 h、168 h裂隙灯显微镜下对角膜进行临床评分并拍照。处死小鼠后,取角膜组织进行HE染色和PAS染色;测定角膜内中性粒细胞和巨噬细胞浸润体积。利用酶联免疫吸附实验对小鼠角膜内的白细胞介素-1β含量进行测定。结果 造模后 0~14 d,两组小鼠体质量与血糖差异均无统计学意义(均为P>0.05)。造模后24 h、36 h、48 h、120 h、168 h,高糖饮食组小鼠角膜临床评分均明显高于模型对照组,差异均有统计学意义(均为P<0.05)。高糖饮食组小鼠角膜穿孔率79.5%,高于模型对照组的40.9%,差异有统计学意义(P=0.000)。造模后各时间点,高糖饮食组中性粒细胞浸润体积均高于模型对照组,差异均有统计学意义(均为P=0.000)。造模后72 h、96 h、120 h、168 h,高糖饮食组巨噬细胞浸润体积均高于模型对照组(均为P=0.000)。角膜组织病理学检查结果示,高糖饮食组炎症反应更重,角膜组织破坏更早且更为严重。造模后24 h、48 h高糖饮食组白细胞介素-1β含量均明显高于模型对照组(均为P<0.05)。结论 高糖饮食加重了真菌性角膜炎感染的严重程度,增强了中性粒细胞、巨噬细胞的趋化,促进了IL-1β的分泌。 相似文献
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Usha Patel Manish Pandey Sadhana Kannan Tanuja A. Samant Poonam Gera Neha Mittal Swapnil Rane Asawari Patil Vanita Noronha Amit Joshi Vijay M. Patil Kumar Prabhash Manoj B. Mahimkar 《British journal of cancer》2020,123(12):1757
Background Anti-EGFR-based therapies have limited success in HNSCC patients. Predictive biomarkers are greatly needed to identify the patients likely to be benefited from these targeted therapies. Here, we present the prognostic and predictive association of biomarkers in HPV-negative locally advanced (LA) HNSCC patients.Methods Treatment-naive tumour tissue samples of 404 patients, a subset of randomised Phase 3 trial comparing cisplatin radiation (CRT) versus nimotuzumab plus cisplatin radiation (NCRT) were analysed to evaluate the expression of HIF1α, EGFR and pEGFR by immunohistochemistry and EGFR gene copy change by FISH. Progression-free survival (PFS), locoregional control (LRC) and overall survival (OS) were estimated by Kaplan–Meier method. Hazard ratios were estimated by Cox proportional hazard models.Results Baseline characteristics of the patients were balanced between two treatment groups (CRT vs NCRT) and were representative of the trial cohort. The median follow-up was of 39.13 months. Low HIF1α was associated with better PFS [HR (95% CI) = 0.62 (0.42–0.93)], LRC [HR (95% CI) = 0.56 (0.37–0.86)] and OS [HR (95% CI) = 0.63 (0.43–0.93)] in the CRT group. Multivariable analysis revealed HIF1α as an independent negative prognostic biomarker. For patients with high HIF1α, NCRT significantly improved the outcomes [PFS:HR (95% CI) = 0.55 (0.37–0.82), LRC:HR (95% CI) = 0.55 (0.36–0.85) and OS:HR (95% CI) = 0.54 (0.36–0.81)] compared to CRT. While in patients with low HIF1α, no difference in the clinical outcomes was observed between treatments. Interaction test suggested a predictive value of HIF1α for OS (P = 0.008).Conclusions High HIF1α expression is a predictor of poor clinical response to CRT in HPV-negative LA-HNSCC patients. These patients with high HIF1α significantly benefited with the addition of nimotuzumab to CRT.Clinical trial registration Registered with the Clinical Trial Registry of India (Trial registration identifier—CTRI/2014/09/004980).Subject terms: Tumour biomarkers, Head and neck cancer, Tumour biomarkers, Head and neck cancer, Predictive markers 相似文献
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Susan E. Hickman Alexia M. Torke Greg A. Sachs Rebecca L. Sudore Anne L. Myers Qing Tang Giorgos Bakoyannis Bernard J. Hammes 《Journal of pain and symptom management》2019,57(6):1143-1150.e5
ContextIt is especially important that patients are well informed when making high-stakes, preference-sensitive decisions like those on the Physician Orders for Life-Sustaining Treatment (POLST) form. However, there is currently no way to easily evaluate whether patients understand key concepts when making these important decisions.ObjectivesTo develop a POLST knowledge survey.MethodsExpert (n = 62) ratings of key POLST facts were used to select items for a POLST knowledge survey. The survey was administered to nursing facility residents (n = 97) and surrogate decision-makers (n = 112). A subset (n = 135) were re-administered the survey after a standardized advance care planning discussion to assess the scale's responsiveness to change.ResultsThe 19-item survey demonstrated adequate reliability (α = 0.72.). Residents' scores (x = 11.4, standard deviation 3.3) were significantly lower than surrogate scores (x = 14.7, standard deviation 2.5) (P < 0.001). Scores for both groups increased significantly after administration of a standardized advance care planning discussion (P < 0.001). Although being a surrogate, age, race, education, cognitive functioning, and health literacy were significantly associated with higher POLST Knowledge Survey scores in univariate analyses, only being a surrogate (P < 0.001) and being white (P = 0.028) remained significantly associated with higher scores in multivariate analyses.ConclusionThe 19-item POLST Knowledge Survey demonstrated adequate reliability and responsiveness to change. Findings suggest the survey could be used to identify knowledge deficits and provide targeted education to ensure adequate understanding of key clinical decisions when completing POLST. 相似文献