Circulating bacterial lipopolysaccharide-induced inflammation reduces flow in brain-irrigating arteries independently from cerebrovascular prostaglandin production

International audienceBrain dysfunction is a frequent complication of the systemic inflammatory response to bacterial infection or sepsis. In the present work, the effects of intravenous bacterial lipopolysaccharide (LPS) administration on cere-bral arterial blood flow were assessed with time-of-flight (TOF)-based magnetic resonance angiography (MRA) in mice. Cerebral expression of the transcription factors nuclear factor-kappaB (NF-jB) and c-Fos and that of enzymes synthesizing vasoactive mediators, such as pros-taglandins and nitric oxide, known to be increased under inflammatory conditions, were studied in the same animals. Time-resolved TOF MRA revealed no differences in blood flow in the internal carotids upstream of the circle of Willis, but indicated lower flow in its lateral parts as well as in the middle and anterior cerebral arteries after intravenous LPS injection as compared to saline administration. Although LPS did not increase c-Fos expression in ventral forebrain structures of these animals, it did induce NF-jB in meningeal blood vessels. LPS also increased cerebral expression of cyclooxygenase-2 and prostaglandin E syn-thase mRNAs, but de novo expression occurred in veins rather than in arteries. In conclusion, our work indicates that LPS-induced systemic inflammation does not necessarily affect filling of the circle of the Willis from the periphery, but that circulating LPS alters outflow from the circle of Willis to the middle and anterior cerebral arteries. These modifications in arterial flow were not related to increased cerebral synthesis of prostaglandins, but may instead be the consequence of the action of circulating prostaglandins and other vasoactive mediators on brain-irrigating arteries during systemic inflammation

Development of a preclinical model of donation after circulatory determination of death for translational application

BACKGROUND: Extracorporeal membranous oxygenation is proposed for abdominal organ procurement from donation after circulatory determination of death (DCD). In France, the national Agency of Biomedicine supervises the procurement of kidneys from DCD, specifying the durations of tolerated warm and cold ischemia. However, no study has determined the optimal conditions of this technique. The aim of this work was to develop a preclinical model of DCD using abdominal normothermic oxygenated recirculation (ANOR). In short, our objectives are to characterize the mechanisms involved during ANOR and its impact on abdominal organs. METHODS: We used Large White pigs weighing between 45 and 55 kg. After 30 minutes of potassium-induced cardiac arrest, the descending thoracic aorta was clamped and ANOR set up between the inferior vena cava and the abdominal aorta for 4 hours. Hemodynamic, respiratory and biochemical parameters were collected. Blood gasometry and biochemistry analysis were performed during the ANOR procedure. RESULTS: Six ANOR procedures were performed. The surgical procedure is described and intraoperative parameters and biological data are presented. Pump flow rates were between 2.5 and 3 l/min. Hemodynamic, respiratory, and biochemical objectives were achieved under reproducible conditions. Interestingly, animals remained hemodynamically stable following the targeted protocol. Arterial pH was controlled, and natremia and renal function remained stable 4 hours after the procedure was started. Decreased hemoglobin and serum proteins levels, concomitant with increased lactate dehydrogenase activity, were observed as a consequence of the surgery. The serum potassium level was increased, owing to the extracorporeal circulation circuit. CONCLUSIONS: Our ANOR model is the closest to clinical conditions reported in the literature and will allow the study of the systemic and abdominal organ impact of this technique. The translational relevance of the pig will permit the determination of new biomarkers and protocols to improve DCD donor management

Indices d’exploitation minière protohistorique dans les Vosges du Sud :

Les recherches récentes menées dans les anciennes mines de cuivre moderne du massif alpin (Val Grigna) au nord du Pays de Galles (Pary’s Mountain) au Royaume-Uni, ou encore en Grèce (mine de Thoricos, dans le district du Laurion), ont apporté de nouveaux indices d’exploitations minières antérieures à l’Âge du Fer. En France, dans le massif vosgien, les recherches se sont concentrées sur la mine de cuivre de la Grande Montagne de Château-Lambert. Plusieurs outils de mineurs macrolithiques ont été découverts dans les parties les plus anciennes de la mine. Ces outils, typiques de l’Âge du Bronze, ont été conçus à partir de galets locaux en granite ou en grauwacke. Cette découverte élargit les connaissances sur les premières mines de cuivre dans cette partie du massif vosgien. Elle pose aussi de nouveaux jalons pour une approche méthodologique multiscalaire des premières exploitations métalliques en Europe (5e au 1er millénaire BC).Recent research exploring ancient modern copper mines in the Alps mountains (Valle Camonica), North Wales (Pary’s mountain), Unitited Kingdom, and Greece (Thorikos mine, Laurion district), provides new evidence of Bronze Age mining. In the Vosges Massif in France, the research focused on one of the largest copper mines in the area : the Château-Lambert Great Mountain Mine. On top of the lode, the assemblage of finds from the survey consists of eight macrolithic mining tools found in the oldest part of the mine. These typical Bronze Age mining tools were made using local granite or grauwacke pebbles found in fluvial or glacial sediments. This discovery greatly expands our knowledge of the first copper mining in this part of Europe. It also sets new standards for a multiscale methodological approach to the first metal mines in Europe (5th to 1st millennium BC).Die neueren Untersuchungen in alten Kupferminen in Val Grigna in den Alpen, in Pary‘s Mountain im Norden von Wales in Großbritannien und in Thorikos im Distrikt von Laurion in Griechenland haben neue Informationen zu den voreisenzeitlichen Bergwerken geliefert. In Frankreich konzentrierten sich die Recherchen auf die Kupfermine von la Grande Montagne in Château-Lambert in den Vogesen. In den ältesten Sektoren des Bergwerks wurden mehrere makrolithische Werkzeuge für den Kupferabbau entdeckt. Die typisch bronzezeitlichen Geräte waren aus lokalem Granit oder Grauwacke gefertigt. Diese Entdeckung bereichert unsere Kenntnis der ersten Kupferminen in diesem Teil der Vogesen. Sie setzt auch neue Maßstäbe für eine methodische, auf mehreren Ebenen basierende Betrachtung der ersten Metallgewinnung in Europa (5. bis 1. Jt. v. Chr.)

Report of the Working Group on the Effects of Extraction of Marine Sediments on the Marine Ecosystem, WGEXT, 31 May-4 June 2010, Djurönäset, Sweden

ICES WGEXT Report 201

Report of the Working Group on the Effects of Extraction of Marine Sediments on the Marine Ecosystem, WGEXT, 11-15 April 2011, Delft, the Netherlands

ICES WGEXT Report 201