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1.
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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Environmental chemical exposure could be an important etiologic factor for geographic differences in breast cancer incidence. In this study, we examined emissions of polycyclic aromatic hydrocarbons (PAHs) and PM2.5 in relation to breast cancer incidence in metro Atlanta and rural Georgia by analyzing data from the Surveillance, Epidemiology, and End Results Program and the Environmental Protection Agency. The results showed that metro Atlanta had a significantly higher age-adjusted annual incidence rate of female breast cancer than rural Georgia (132.6 vs. 113.7 per 100,000) for 1992–2011. Emissions of both PAHs [adjusted β = 0.568 (95 % CI: 0.209, 0.927); p = 0.004] and PM2.5 [adjusted β = 2.964 (95 % CI: 0.468, 5.459); p = 0.023] were significantly associated with breast cancer incidence in metro Atlanta area. This study suggests that ambient air pollution, especially PAHs and PM2.5, could have a significant impact on the increased incidence of female breast cancer in urban areas.  相似文献   
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Introduction: There are at the minimum two major, quite different approaches to advance drug discovery. The first being the target-based drug discovery (TBDD) approach that is commonly referred to as the molecular approach. The second approach is the phenotype-based drug discovery (PBDD), also known as physiology-based drug discovery or empirical approach.

Area covered: The authors discuss, herein, the need for developing radiation countermeasure agents for various sub-syndromes of acute radiation syndromes (ARS) following TBDD and PBDD approaches. With time and continuous advances in radiation countermeasure drug development research, the expectation is to have multiple radiation countermeasure agents for each sub-syndrome made available to radiation exposed victims.

Expert opinion: The majority of the countermeasures currently being developed for ARS employ the PBDD approach, while the TBDD approach is clearly under-utilized. In the future, an improved drug development strategy might be a ‘hybrid’ strategy that is more reliant on TBDD for the initial drug discovery via large-scale screening of potential candidate agents, while utilizing PBDD for secondary screening of those candidates, followed by tertiary analytics phase in order to pinpoint efficacious candidates that target the specific sub-syndromes of ARS.  相似文献   

5.

Background

Physicians treating nonvalvular atrial fibrillation (AF) assess stroke and bleeding risks when deciding on anticoagulation. The agreement between empirical and physician-estimated risks is unclear. Furthermore, the association between patient and physician sex and anticoagulation decision-making is uncertain.

Methods

We pooled data from 2 national primary care physician chart audit databases of patients with AF (Facilitating Review and Education to Optimize Stroke Prevention in Atrial Fibrillation and Coordinated National Network to Engage Physicians in the Care and Treatment of Patients with Atrial Fibrillation Chart Audit) with a combined 1035 physicians (133 female, 902 male) and 10,927 patients (4567 female and 6360 male).

Results

Male physicians underestimated stroke risk in female patients and overestimated risk in male patients. Female physicians estimated stroke risk well in female patients but underestimated the risk in male patients. Risk of bleeding was underestimated in all. Despite differences in risk assessment by physician and patient sex, > 90% of patients received anticoagulation across all subgroups. There was modest agreement between physician estimated and calculated (ie, CHADS2 score) stroke risk: Kappa scores were 0.41 (0.35-0.47) for female physicians and 0.34 (0.32-0.36) for male physicians.

Conclusions

Our study is the first to examine the association between patient and physician sex influences and stroke and bleeding risk estimation in AF. Although there were differences in agreement between physician estimated stroke risk and calculated CHADS2 scores, these differences were small and unlikely to affect clinical practice; further, despite any perceived differences in the accuracy of risk assessment by sex, most patients received anticoagulation.  相似文献   
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Background Beating heart surgery has now become the commonest technique of doing Coronary Artery Bypass Graft Surgery (CABG) in our country. It is being used even in such high risk situations like diffuse coronary disease and Critical Left Main stem Stenosis (LMCS) with good results. The aim of this study is to retrospectively review our results in Off-Pump Coronary Artery Bypass Surgery (OPCAB) in patients with critical left main stem stenosis. Methods This study is a retrospective analysis of the data of patients who underwent primary coronary artery bypass surgery. During the period from April 2003 to September 2005 a total of 64 patients underwent OPCAB procedure for critical LMCS. During the same period 10 patients underwent CABG on Cardio Pulmonary Bypass (CPB). The age range was 36–77yrs. The sex distribution was M: F 53∶10. Ten patients were done as emergency. 2 of them were on Intra Aortic Balloon Pump (IABP) support preoperatively. 10 patients were high risk with a Euro score of ≥5. Results Left Internal Mammary Artery (LIMA) was used in 78% of cases. Average grafts per patient was 2.96. The median ventilation time was 5.91 hrs. New IABP insertion in postoperative period was required in 1 patient. One patient was reexplored for bleeding. There was one perioperative myocardial infarction. 57% of patients did not need any blood transfusion. There was no conversion to CPB. There was no operative mortality. Inotropes were used in ten cases. Conclusions OPCAB is a safe method of revascularization in patients with critical LMCS. Preoperative IABP is useful in patients with cardiogenic shock. However, there is a place for CPB in patients needing additional procedures like Mitral Valve repair (MV repair) or Dor's procedure or when the vessels are very diffusely diseased. Those patients who are unstable despite IABP support may be managed by Beating heart On Pump (BHOP) technique.  相似文献   
8.
CXCL12 and its receptor, CXCR4, are emerging as promising targets for modulating growth, angiogenesis, and metastasis in several human cancers. Indeed, blocking the receptor is sufficient to prevent metastasis and angiogenesis in experimental breast cancer xenografts. Recently, the biological effect of the CXCR4 in pancreatic cancer, one of the most deadly neoplastic diseases, has been reported. However, the molecular mechanism by which CXCR4 contributes to these properties is not completely understood. In this paper, we characterize the signaling pathways activated by CXCR4 in pancreatic cancer. We show that after CXCR4 activation, EGFR becomes tyrosine phosphorylated, and the kinase activity of this receptor, together with the activation of MMPs, Src, and PI3-Kinase, is required for CXCR4-mediated ERK activation. Analysis of this cascade in pancreatic cancer cells revealed that the ERK-mediated pathway regulates genes involved in angiogenesis, such as VEGF, CD44, HIF1α, and IL-8. Furthermore, ERK blockage inhibits the migration and tube formation of endothelial cells induced by CXCL12. Considering that inhibitors for several components of this pathway, including CXCR4 itself, are at different stages of clinical trials, this study provides theoretical justification for the clinical testing of these drugs in pancreatic cancer, thus extending the list of potential targets for treating this dismal disease.  相似文献   
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1. The frequent occurrence of hypothalamo-pituitary dysfunction in patients with eating disorders as well as prior reports that nutritional and endocrine status influence pituitary morphology, led us to hypothesize that pituitary size and shape may be altered in patients with eating disorders. 2. Magnetic resonance imaging (MRI) does not use ionizing radiation and is currently one of the most feasible modalities available to study the pituitary gland in vivo. Using MRI, we have previously reported in a preliminary study that female patients with eating disorders had significantly smaller pituitary glands than controls. In addition MRI excluded any pituitary mass lesions. 3. In this report, we confirm our previous MRI findings and provide further evidence of pituitary abnormalities in an expanded sample of eating disorder patients. Preliminary data on pituitary volume estimates from MRI scans are provided for a subset of patients and controls.  相似文献   
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