The James Webb Space Telescope mission

Instrumentatio

External validation of the diffuse intrinsic pontine glioma survival prediction model: a collaborative report from the International DIPG Registry and the SIOPE DIPG Registry

We aimed to perform external validation of the recently developed survival prediction model for diffuse intrinsic pontine glioma (DIPG), and discuss its utility. The DIPG survival prediction model was developed in a cohort of patients from the Netherlands, United Kingdom and Germany, registered in the SIOPE DIPG Registry, and includes age <3 years, longer symptom duration and receipt of chemotherapy as favorable predictors, and presence of ring-enhancement on MRI as unfavorable predictor. Model performance was evaluated by analyzing the discrimination and calibration abilities. External validation was performed using an unselected cohort from the International DIPG Registry, including patients from United States, Canada, Australia and New Zealand. Basic comparison with the results of the original study was performed using descriptive statistics, and univariate- and multivariable regression analyses in the validation cohort. External validation was assessed following a variety of analyses described previously. Baseline patient characteristics and results from the regression analyses were largely comparable. Kaplan–Meier curves of the validation cohort reproduced separated groups of standard (n = 39), intermediate (n = 125), and high-risk (n = 78) patients. This discriminative ability was confirmed by similar values for the hazard ratios across these risk groups. The calibration curve in the validation cohort showed a symmetric underestimation of the predicted survival probabilities. In this external validation study, we demonstrate that the DIPG survival prediction model has acceptable cross-cohort calibration and is able to discriminate patients with short, average, and increased survival. We discuss how this clinico-radiological model may serve a useful role in current clinical practice

Metal uptake by homegrown vegetables – The relative importance in human health risk assessments at contaminated sites

Risk assessments of contaminated land often involve the use of generic bioconcentration factors (BCFs),which express contaminant concentrations in edible plant parts as a function of the concentration in soil,in order to assess the risks associated with consumption of homegrown vegetables. This study aimed toquantify variability in BCFs and evaluate the implications of this variability for human exposure as-sessments, focusing on cadmium (Cd) and lead (Pb) in lettuce and potatoes sampled around 22 con-taminated glassworks sites. In addition, risks associated with measured Cd and Pb concentrations in soiland vegetable samples were characterized and a probabilistic exposure assessment was conducted toestimate the likelihood of local residents exceeding tolerable daily intakes. The results show that con-centrations in vegetables were only moderately elevated despite high concentrations in soil, and mostsamples complied with applicable foodstuff legislation. Still, the daily intake of Cd (but not Pb) wasassessed to exceed toxicological thresholds for about afifth of the study population. Bioconcentrationfactors were found to vary more than indicated by previous studies, but decreasing BCFs with increasingmetal concentrations in the soil can explain why the calculated exposure is only moderately affected bythe choice of BCF value when generic soil guideline values are exceeded and the risk may be un-acceptable.</p