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International audience; BACKGROUND: Sodium-23 magnetic resonance imaging ((23)Na MRI) allows non-invasive assessment of tissue sodium concentration ([Na(+)]). Age and chronic kidney disease (CKD) are associated with increased tissue [Na(+)] in adults, but limited information is available pertaining to children and adolescents. We hypothesized that pediatric CKD is associated with altered tissue [Na(+)] compared to healthy controls. METHODS: This was a case-control exploratory study on healthy children and adults and pediatric CKD patients. Study participants underwent an investigational visit, blood/urine biochemistry, and leg (23)Na MRI for tissue [Na(+)] quantification (whole leg, skin, soleus muscle). CKD was stratified by etiology and patients' tissue [Na(+)] was compared against healthy controls by computing individual Z-scores. An absolute Z-score \textgreater 1.96 was deemed to deviate significantly from the mean of healthy controls. Pearson correlation was used to compute the associations between tissue [Na(+)] and kidney function. RESULTS: A total of 36 pediatric participants (17 healthy, 19 CKD) and 19 healthy adults completed the study. Healthy adults had significantly higher tissue [Na(+)] compared with pediatric groups; conversely, no significant differences were found between healthy children/adolescents and CKD patients. Four patients with glomerular disease and one kidney transplant recipient due to atypical hemolytic-uremic syndrome had elevated whole-leg [Na(+)] Z-scores. Reduced whole-leg [Na(+)] Z-scores were found in two patients with tubular disorders (Fanconi syndrome, proximal-distal renal tubular acidosis). All tissue [Na(+)] measures were significantly associated with proteinuria and hypoalbuminemia. CONCLUSIONS: Depending on etiology, pediatric CKD was associated with either increased (glomerular disease) or reduced (tubular disorders) tissue [Na(+)] compared with healthy controls. A higher resolution version of the Graphical abstract is available as Supplementary information.

Die Preisvolatilität hat in Deutschland im Zeitraum 1993-2008 für wichtige Agrarprodukte (Weizen, Gerste und Milch) vor allem aufgrund der Deregulierung der EU-Märkte zugenommen. Für andere Produkte hat sich die Preisvolatilität in diesem Zeitraum wenig geändert, was vor allem daran liegt, dass das Ausmaß der Marktregulierung über diesen Zeitraum stabil war. Im Rahmen von Simulationen mit dem Agrarsektormodell ESIM wurde gezeigt, dass es aufgrund der starken Weltmarktintegration bei Weizen, Gerste und Raps keinen erlösstabilisierenden Zusammenhang zwischen den Ertrags- und den Preisschwankungen in Deutschland gibt, da das auch in Deutschland maßgebliche Weltmarktpreisniveau nicht wesentlich durch das Ertragsniveau in Deutschland determiniert wird. Ein potenzieller Anstieg der globalen Ertragsvariabilität, der sich langfristig in Folge des globalen Klimawandels einstellen könnte, würde zu einem Anstieg der Preisvolatilität führen. Forderungen nach einer staatlichen Subventionierung von Ernteversicherungen aufgrund des hohen systemischen Risikos und daraus resultierenden Marktversagens haben in den letzten Jahren zugenommen. Bisher fehlt allerdings der empirische Nachweis dafür, dass das systemische Risiko in seiner Höhe nicht durch marktwirtschaftliche Instrumente und ohne Subventionierung beherrschbar ist., C2_2