Uveal Melanoma Patients Have a Distinct Metabolic Phenotype in Peripheral Blood

Uveal melanomas (UM) are detected earlier. Consequently, tumors are smaller, allowing for novel eye-preserving treatments. This reduces tumor tissue available for genomic profiling. Additionally, these small tumors can be hard to differentiate from nevi, creating the need for minimally invasive detection and prognostication. Metabolites show promise as minimally invasive detection by resembling the biological phenotype. In this pilot study, we determined metabolite patterns in the peripheral blood of UM patients (n = 113) and controls (n = 46) using untargeted metabolomics. Using a random forest classifier (RFC) and leave-one-out cross-validation, we confirmed discriminatory metabolite patterns in UM patients compared to controls with an area under the curve of the receiver operating characteristic of 0.99 in both positive and negative ion modes. The RFC and leave-one-out cross-validation did not reveal discriminatory metabolite patterns in high-risk versus low-risk of metastasizing in UM patients. Ten-time repeated analyses of the RFC and LOOCV using 50% randomly distributed samples showed similar results for UM patients versus controls and prognostic groups. Pathway analysis using annotated metabolites indicated dysregulation of several processes associated with malignancies. Consequently, minimally invasive metabolomics could potentially allow for screening as it distinguishes metabolite patterns that are putatively associated with oncogenic processes in the peripheral blood plasma of UM patients from controls at the time of diagnosis.</p

Purification and characterisation of post-consumer plastic pyrolysis oil fractionated by vacuum distillation

Valorisation of post-consumer plastic pyrolysis oil in steam crackers and their application as precursors to chemicals is currently hindered by the complexity of these oils in terms of their boiling range, the risk of fouling by unsaturated compounds, and the presence of contaminations (heteroatoms, metals, and halogens). To gain insights into which of these challenges is actually a potential showstopper, we have studied the vacuum distil-lation of pyrolysis oil derived from two sorted post-consumer waste plastics, i.e. polypropylene (PP) rigids and mixed polyolefins (MPO) rigids, in a batch fractionating column. The crude pyrolysis oil samples were distilled in three fractions i.e., the light fraction (final boiling point 360 degrees C). Subsequently, comprehensive characterisation, such as physicochemical properties, the level of contaminations, and chemical composition, was performed. The suitability of the light and middle fractions for steam cracking and precursors to chemical feedstock was assessed. It was found that the density and viscosity values of light and middle fractions from the two pyrolysis oil samples were comparable to fossil naphtha and diesel, whereas total acid number (TAN) values were notably higher compared to petroleum -based oil fractions (>0.5 mgKOH/g). Analyses via GC-MS and ATR-FTIR revealed predominant concentrations of olefins. ICP-OES analysis showed that distillation removes more than 97.5% of metals in all fractions. The chlorine content (>3 ppm), nitrogen (>0.1%), and oxygen (>0.1%) exceed thresholds. Hence, this study shows that vacuum distillation effectively improved most, but not all, of the properties of the distilled fractions and can thus be an essential downstream process step for the application of post-consumer plastic pyrolysis oils as feedstock in steam crackers and precursors to chemicals