International challenge to model the long-range transport of radioxenon released from medical isotope production to six Comprehensive Nuclear-Test-Ban Treaty monitoring stations.

After performing a first multi-model exercise in 2015 a comprehensive and technically more demanding atmospheric transport modelling challenge was organized in 2016. Release data were provided by the Australian Nuclear Science and Technology Organization radiopharmaceutical facility in Sydney (Australia) for a one month period. Measured samples for the same time frame were gathered from six International Monitoring System stations in the Southern Hemisphere with distances to the source ranging between 680 (Melbourne) and about 17,000 km (Tristan da Cunha). Participants were prompted to work with unit emissions in pre-defined emission intervals (daily, half-daily, 3-hourly and hourly emission segment lengths) and in order to perform a blind test actual emission values were not provided to them. Despite the quite different settings of the two atmospheric transport modelling challenges there is common evidence that for long-range atmospheric transport using temporally highly resolved emissions and highly space-resolved meteorological input fields has no significant advantage compared to using lower resolved ones. As well an uncertainty of up to 20% in the daily stack emission data turns out to be acceptable for the purpose of a study like this. Model performance at individual stations is quite diverse depending largely on successfully capturing boundary layer processes. No single model-meteorology combination performs best for all stations. Moreover, the stations statistics do not depend on the distance between the source and the individual stations. Finally, it became more evident how future exercises need to be designed. Set-up parameters like the meteorological driver or the output grid resolution should be pre-scribed in order to enhance diversity as well as comparability among model runs.

Serum levels of the adipokine chemerin are increased in preeclampsia during and 6 months after pregnancy.

UNLABELLED: Preeclampsia is a serious cardiovascular complication in pregnancy which is associated with an increased future metabolic and cardiovascular risk for mother and newborn. Recently, chemerin was introduced as a novel adipokine inducing insulin resistance in vitro and in vivo. In the current study, we investigated serum concentrations of chemerin by ELISA in control and preeclampsia patients during pregnancy ( CONTROL: n=37, preeclampsia: n=37) and 6 months after delivery ( CONTROL: n=35, preeclampsia: n=36). Furthermore, the association between chemerin and markers of renal function, glucose and lipid metabolism, as well as inflammation was studied in pregnant patients. Median maternal chemerin concentrations were significantly elevated in preeclampsia patients (249.5 [range: 123.1-366.9] µg/l) as compared to controls (204.8 [138.5-280.8] µg/l) (p<0.001). Furthermore, chemerin serum levels positively correlated with blood pressure, creatinine, free fatty acids, cholesterol, triglycerides (TG), leptin, adiponectin, and C-reactive protein in univariate analyses. In multivariate analyses, TG and leptin remained independently associated with circulating chemerin. Interestingly, median chemerin concentrations 6 months after delivery remained significantly higher in former preeclampsia patients (196.0 [119.8-368.7] µg/l) as compared to controls (152.2 [102.8-216.4] µg/l). Taken together, maternal chemerin serum concentrations are significantly increased in preeclampsia during and after pregnancy. Furthermore, TG and leptin are independent predictors of circulating chemerin during pregnancy.

Serum levels of the adipokine zinc-α2-glycoprotein are increased in chronic hemodialysis.

Zinc-α2-glycoprotein (ZAG) has recently been proposed as a new adipokine involved in body weight control. In the current study, we investigated renal elimination of this adipokine by comparing circulating ZAG levels in patients on chronic hemodialysis (CD) with controls. Sixty CD patients and 60 controls with a glomerular filtration rate greater than 50 mL/min were included. Serum concentrations of ZAG were determined by enzyme-linked immunosorbent assay; and its relationship with renal function, glucose and lipid metabolism, as well as inflammation was studied in both groups. Median ZAG serum levels were almost 2-fold higher in CD patients (94.4 ± 29.4 mg/L) as compared with controls (48.3 ± 23.5 mg/L) (P < .001). Furthermore, circulating ZAG was negatively correlated with fasting insulin, homeostasis model assessment of insulin resistance, and leptin in controls in univariate analysis. Moreover, CD independently predicted ZAG concentrations in multiple regression analysis. Renal filtration appears to be an important route of ZAG elimination, and markers of renal function should be included in studies on ZAG physiology.