A dual generalization of convex functions

As it is well known, the convexity property of a function may be described by the quasiconvexity property of all "the dual perturbations" of this function. If we consider the "dual perturbation" only in a subset $M\subset X^{\ast}$ we obtain a general class of functions called $M$-convex. In this paper we establish some special properties and a continuity theorem of this new type of functions

Clinical and genetic characterization of FIPA (familial isolated pituitary adenomas)

peer reviewedPituitary adenomas are common brain tumours at autopsy and radiological series of unselected population. Historically, few epidemiologic data regarding the prevalence of clinically apparent pituitary adenomas have been available. Recently, a cross-sectional study conducted in Liege, Belgium, noted that clinically-apparent pituitary adenomas occurred with a prevalence of 1:1064 inhabitants, which is 3.5-5 times the previously reported prevalence. Pituitary adenomas occur predominantly as sporadic tumors, but also in a familial setting or associated to some familial/isolated tumoral syndromes. The recent characterization of the novel clinical entity FIPA (Familial Isolated Pituitary Adenomas) increased the prevalence of familial pituitary adenomas which account now for about 5% of pituitary tumors. Distinct genetic mechanisms are continuously identified and increase our understanding of the complex clinical presentation and sometimes unpredictable evolution of pituitary adenomas.Les adénomes hypophysaires représentent une pathologie fréquente parmi les tumeurs cérébrales. Une étude liégeoise récente a montré une prévalence des adénomes hypophysaires cliniquement actifs de 1: 1.064 habitants, nettement supérieure aux données antérieures. Tant dans les séries cliniques qu'autopsiques, les microadénomes à prolactine sont les adénomes prédominants. Les adénomes hypophysaires sont le plus souvent de présentation sporadique, mais des adénomes familiaux dans des formes isolées ou syndromiques sont également décrits. Les adénomes hypophysaires familiaux représentent environ 5% des adénomes hypophysaires et leur caractérisation clinique et génétique a été récemment enrichie par la description de la nouvelle entité FIPA (Familial Isolated Pituitary Adenomas) et des mutations du gène AIP (Aryl hydrocarbon receptor-Interacting Protein). Bien que d'évolution habituellement bénigne, les adénomes hypophysaires sont caractérisés par une grande diversité clinique et génétique qui réclame des moyens diagnostiques et thérapeutiques spécifiques

Magnesium-based interventions for normal kidney function and chronic kidney disease

Magnesium (Mg) is one of the most important cations in the body, playing an essential role in biological systems as co-factor for more than 300 essential enzymatic reactions. In the general population, low levels of Mg are associated with a high risk of cardio-vascular disease (CVD). Despite the accumulating literature data, the effect of Mg administration on mortality in chronic kidney disease (CKD) patients has never been investigated as a primary end-point. We conducted a systematic search of studies assessing the benefits and harms of Mg in CKD (stages 1 to 5 and 5D), and considered all randomized controlled trials (RCTs) and quasi-RCTs evaluating Mg-based interventions in CKD. As a phosphate binder, Mg salts offer a plausible opportunity for doubly favorable effects via reduction of intestinal phosphate absorption and addition of potentially beneficial effects via increasing circulating Mg levels. Mg supplementation might have a favorable effect on vascular calcification, although evidence for this is very slight. Although longitudinal data describe an association between low serum Mg levels and increased total and cardiovascular mortality, in patients with CKD, the existing RCTs reporting the effect of Mg supplementation on mortality failed to demonstrate any favorable effect. As with many other variables that influence hard end-points in nephrology, the role of Mg in CKD patients needs to be investigated in more depth. Additional research that is well-designed and directly targeting the role of Mg is needed as a consequence of limited existing evidence.status: publishe