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Circulating ceramides as biomarkers of cardiovascular disease: Evidence from phenotypic and genomic studies.There is a need for new biomarkers of atherosclerotic cardiovascular disease (ACVD), the main cause of death globally. Ceramides, a class of potent bioactive lipid mediators, have signalling roles in apoptosis, cellular stress and inflammation. Recent studies have highlighted circulating ceramides as novel biomarkers of coronary artery disease, type-2 diabetes and insulin resistance. Ceramides are highly regulated by enzymatic reactions throughout the body in terms of their activity and metabolism, including production, degradation and transport. The genetic studies that have been completed to date on the main ceramide species found in circulation are described, highlighting the importance of DNA variants in genes involved in ceramide biosynthesis as key influencers of heritable, circulating ceramide levels. We also review studies of disease associations with ceramides and discuss mechanistic insights deriving from recent genomic studies. The signalling activities of ceramides in vascular inflammation and apoptosis, associations between circulating ceramides and coronary artery disease risk, type-2 diabetes and insulin resistance, and the potential importance of ceramides with regard to ACVD risk factors, such as blood pressure, lipoproteins and lifestyle factors, are also discussed. [Abstract copyright: Copyright © 2021 The Author(s). Published by Elsevier B.V. All rights reserved.]
Reliability and prognostic value of radiomic features are highly dependent on choice of feature extraction platformAbstract: Objective: To investigate the effects of Image Biomarker Standardisation Initiative (IBSI) compliance, harmonisation of calculation settings and platform version on the statistical reliability of radiomic features and their corresponding ability to predict clinical outcome. Methods: The statistical reliability of radiomic features was assessed retrospectively in three clinical datasets (patient numbers: 108 head and neck cancer, 37 small-cell lung cancer, 47 non-small-cell lung cancer). Features were calculated using four platforms (PyRadiomics, LIFEx, CERR and IBEX). PyRadiomics, LIFEx and CERR are IBSI-compliant, whereas IBEX is not. The effects of IBSI compliance, user-defined calculation settings and platform version were assessed by calculating intraclass correlation coefficients and confidence intervals. The influence of platform choice on the relationship between radiomic biomarkers and survival was evaluated using univariable cox regression in the largest dataset. Results: The reliability of radiomic features calculated by the different software platforms was only excellent (ICC > 0.9) for 4/17 radiomic features when comparing all four platforms. Reliability improved to ICC > 0.9 for 15/17 radiomic features when analysis was restricted to the three IBSI-compliant platforms. Failure to harmonise calculation settings resulted in poor reliability, even across the IBSI-compliant platforms. Software platform version also had a marked effect on feature reliability in CERR and LIFEx. Features identified as having significant relationship to survival varied between platforms, as did the direction of hazard ratios. Conclusion: IBSI compliance, user-defined calculation settings and choice of platform version all influence the statistical reliability and corresponding performance of prognostic models in radiomics. Key Points: • Reliability of radiomic features varies between feature calculation platforms and with choice of software version. • Image Biomarker Standardisation Initiative (IBSI) compliance improves reliability of radiomic features across platforms, but only when calculation settings are harmonised. • IBSI compliance, user-defined calculation settings and choice of platform version collectively affect the prognostic value of features.
Shock wave lithotripsy, for the treatment of kidney stones, results in changes to routine blood tests and novel biomarkers: a prospective clinical pilot-studyAbstract: Background: The number of patients undergoing shock wave lithotripsy (SWL) for kidney stones is increasing annually, and as such the development of post-operative complications, such as haematuria and acute kidney injury (AKI) following SWL, is likely to increase. The aim of the study was to evaluate changes in routine blood and novel biomarkers following SWL, for the treatment of kidney stones. Methods: Twelve patients undergoing SWL for solitary unilateral kidney stones were recruited. From patients (8 males and 4 females) aged between 31 and 72 years (median 43 years), venous blood samples were collected pre-operatively (baseline), at 30, 120 and 240 min post-operatively. Routine blood tests were performed using a Sysmex XE-5000, and Beckman Coulter AU5800 and AU680 analysers. NGAL, IL-18, IL-6, TNF-α, IL-10 and IL-8 concentrations were determined using commercially available ELISA kits. Results: Significant (p ≤ 0.05) changes were observed in several blood parameters following SWL. NGAL concentration significantly increased, with values peaking at 30 min post-treatment (p = 0.033). Although IL-18 concentration increased, these changes were not significant (p = 0.116). IL-6 revealed a statistically significant rise from pre-operative up to 4 h post-operatively (p < 0.001), whilst TNF-α significantly increased, peaking at 30 min post-SWL (p = 0.05). There were no significant changes to IL-10 and IL-8 concentrations post-SWL (p > 0.05). Conclusions: Changes to routine blood tests and specific biomarkers, in the future, may be more useful for clinicians. In turn, identification of a panel of biomarkers could provide valuable data on “normal” physiological response after lithotripsy. Ultimately, studies could be expanded to identify or predict those patients at increased risk of developing post-operative complications, such as acute kidney injury or. These studies, however, need validating involving larger cohorts.