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Objectives Aldosterone and renin determinations play an important role in the etiological diagnosis of secondary hypertension. The analytical performances of new aldosterone and renin immunoassays on the Lumipulse G600II® system (Fujierbio) were investigated and compared with those of the iSYS® system (IDS) on patients concerned by medical investigations in a context of suspected or proven Primary aldosteronism. Methods By using the Lumipulse® G Aldosterone and Renin assays we performed imprecision study, linearity and method comparison (n=107). Accuracy of this new renin assay was tested using the International Standard (WHO IS 68/356). We also assessed the equivalence of the different samples types (n=29). Results The imprecision evaluation showed all CVs ® G Aldosterone and Renin assays respectively. The linearity was excellent over the clinical range and the comparison with the iSYS® assays (n=79) showed a strong correlation (R2=1) despite a slight tendency to underestimation (bias of −17.53 pg/mL or 48.56 pmol/L for aldosterone and −15.395 pg/mL for renin). Moreover, the contingency studies based on diagnostic criteria showed that Lumipulse® G results lead to the same clinical diagnosis that iSYS® results. A clear correlation was obtained between EDTA and heparin plasma as well as with the serum for all range of measures. Conclusions The Lumipulse® G Aldosterone and Renin assays present performances compatible with a routine use in medical laboratories. The precise quantification in the low range can be of interest in some clinical contexts especially standing/laying tests. However, the standardisation against the WHO International Standard Renin would be advisable.

BACKGROUND AND AIMS In healthy subjects, normal values of magnesium (Mg) are in the range 0.75–0.95 mmol/L. In the circulation, 65–70% of the Mg is present in the free, ionized and dialyzable form (i.e. 0.45– 0.60 mmol/L), 20% is bound to proteins and 15% is complexed. In chronic kidney disease (CKD) dialysis patients, the dialysate Mg concentration is a major determinant of Mg balance. The aim of this study was to assess the systemic variations of ionized Mg (iMg), as well as that of ionized calcium (iCa), before and after a dialysis session. METHOD A total of 121 dialysis patients [median age = 70 (62.5–78.2) years; 74 male/46 female] in maintenance haemodialysis three times per week, for at least 6 months and with no residual function, were included. Patients were assigned to a single dialysis session with either control fluid (group 1: 3 mM acetate, 1.5 mM Ca, 0.5 mM Mg), or citrate dialysis fluid containing 0.5 mM Mg (group 2: 0.8 mM citrate, 0.3 mM acetate, 1.65 mM Ca) or 0.75 mM Mg (group 3: 0.8 mM citrate, 0.3 mM acetate, 1.65 mM Ca). Blood samples were drawn before and after the midweek dialysis sessions as part of the routine patient follow-up and quality assurance process. iMg and iCa concentrations were measured by direct ion-selective electrode on Nova Stat Profile Prime Plus® (Nova Biomedical). Total Mg (tMg) and Ca (tCa) were assessed by colorimetric method c702/Cobas 8000 analyzer (Roche). Dialytic balance was assessed by the median intra-dialytic difference between pre-dialysis and post-dialysis. RESULTS The use of all types of dialysates (whatever their composition was) was associated with a calcium load during the session (Table). In addition, an Mg loss was observed in both control and citrate dialysis fluid groups containing 0.5 mM Mg. The dialysis session induced a significant decrease in iMg (13 and 22% in group1 and group 2 respectively). By contrast, the use of citrate dialysis fluid with 0.75 mM Mg led to a positive balance with a median intra-dialytic increase of 0.08 and 0.02 mmol/L in tMg and iMg respectively (Table), corresponding to a median increase of 8 and 3% in tMg and iMg respectively. CONCLUSION The iMg fraction represents 70% of tMg in CKD stage 5D patients. While a dialysate Mg concentration at 0.5 mM leads to a negative balance, increasing the concentration to 0.75 mM significantly raises post-dialysis circulating Mg levels in these patients. Therefore, monitoring of iMg should allow a personalized prescription in dialysate Mg composition.

L’agriculture irriguee produit plus de 40 % de l’alimentation mondiale sur moins de 20 % des terres cultivees. L’irrigation, qui consiste a agir sur le cycle naturel de l’eau pour conduire et securiser les cultures dans des contextes geographiques ou les pluies sont soit insuffisantes soit aleatoires, est indispensable a la securite alimentaire mondiale sujette au defi demographique. Pour autant, les enjeux d’une agriculture irriguee durable sont multiples pour repondre aux necessites actuelles et futures : gestion integree de la ressource en eau, equite sociale pour les agriculteurs par rapport a l’allocation des terres et de l’eau, viabilite economique et financiere des systemes irrigues, gouvernance de l’eau et institutions adaptees, economie d’eau et valorisation des eaux usees, pratiques agroecologiques pour concilier productivite et defis environnementaux et climatiques, et preservation de la biodiversite, sont autant de dimensions dont il est necessaire de tenir compte. Cet ouvrage apporte des eclairages sur ces differents defis, a partir de retours d’experiences issus de plusieurs decennies d’actions de developpement de l’agriculture irriguee a l’international, conduites en particulier dans le cadre du projet COSTEA (comite scientifique et technique de l’Eau agricole). Il interessera les decideurs en charge des politiques agricoles et d’irrigation, les operateurs du developpement et toute personne concernee par la pluralite des enjeux de l’agriculture irriguee. Cet ouvrage a ete realise par un collectif d’auteurs engages dans le projet COSTEA, et coordonne par S. Bouarfa, F. Brelle et C. Coulon.