Ovine Fetal Thymus Response to Lipopolysaccharide-Induced Chorioamnionitis and Antenatal Corticosteroids

RATIONALE: Chorioamnionitis is associated with preterm delivery and involution of the fetal thymus. Women at risk of preterm delivery receive antenatal corticosteroids which accelerate fetal lung maturation and improve neonatal outcome. However, the effects of antenatal corticosteroids on the fetal thymus in the settings of chorioamnionitis are largely unknown. We hypothesized that intra-amniotic exposure to lipopolysaccharide (LPS) causes involution of the fetal thymus resulting in persistent effects on thymic structure and cell populations. We also hypothesized that antenatal corticosteroids may modulate the effects of LPS on thymic development. METHODS: Time-mated ewes with singleton fetuses received an intra-amniotic injection of LPS 7 or 14 days before preterm delivery at 120 days gestational age (term = 150 days). LPS and corticosteroid treatment groups received intra-amniotic LPS either preceding or following maternal intra-muscular betamethasone. Gestation matched controls received intra-amniotic and maternal intra-muscular saline. The fetal intra-thoracic thymus was evaluated. RESULTS: Intra-amniotic LPS decreased the cortico-medullary (C/M) ratio of the thymus and increased Toll-like receptor (TLR) 4 mRNA and CD3 expression indicating involution and activation of the fetal thymus. Increased TLR4 and CD3 expression persisted for 14 days but Foxp3 expression decreased suggesting a change in regulatory T-cells. Sonic hedgehog and bone morphogenetic protein 4 mRNA, which are negative regulators of T-cell development, decreased in response to intra-amniotic LPS. Betamethasone treatment before LPS exposure attenuated some of the LPS-induced thymic responses but increased cleaved caspase-3 expression and decreased the C/M ratio. Betamethasone treatment after LPS exposure did not prevent the LPS-induced thymic changes. CONCLUSION: Intra-amniotic exposure to LPS activated the fetal thymus which was accompanied by structural changes. Treatment with antenatal corticosteroids before LPS partially attenuated the LPS-induced effects but increased apoptosis in the fetal thymus. Corticosteroid administration after the inflammatory stimulus did not inhibit the LPS effects on the fetal thymus

Électrode à électrocatalyseur lamellaire poreux en alliage métallique exempt d'ionomère

[EN] The invention relates to a new kind of electrocatalyst to be incorporated as part of the electrodes, anode and cathode, in water electrolysers aimed for hydrogen production through the electrochemical splitting of water into oxygen and hydrogen. The electrocatalyst is characterized by a layered and porous structure that provides a high performance towards the oxygen evolution reaction in the absence of added ionomer. The object of the invention is framed in the field of energy.[FR] L'invention concerne un nouveau type d'électrocatalyseur destiné à être incorporé en tant que partie dans les électrodes, anode et cathode, dans des électrolyseurs d'eau destinés à la production d'hydrogène par fractionnement électrochimique de l'eau en oxygène et en hydrogène. L'électrocatalyseur est caractérisé par une structure lamellaire et poreuse qui assure une performance élevée pour ce qui est de la réaction de dégagement d'oxygène en l'absence d'ionomère ajouté. L'objet de l'invention relève du domaine de l'énergie.Peer reviewedConsejo Superior de Investigaciones Científicas, Universidad de Castilla-La Mancha, Fundación Domingo MartínezA1 Solicitud de patente con informe sobre el estado de la técnic

Électrode électrocatalyseur en alliage métallique à couches sans ionomères poreux

The invention relates to a new kind of electrocatalyst to be incorporated as part of the electrodes, anode and cathode, in water electrolysers aimed for hydrogen production through the electrochemical splitting of water into oxygen and hydrogen. The electrocatalyst is characterized by a layered and porous structure that provides a high performance towards the oxygen evolution reaction in the absence of added ionomer. The object of the invention is framed in the field of energy.Peer reviewedConsejo Superior de Investigaciones Científicas, Universidad de Castilla-La Mancha, Fundación Domingo MartínezA1 Solicitud de patente con informe sobre el estado de la técnic

Recent Advances in Alkaline Exchange Membrane Water Electrolysis and Electrode Manufacturing

Water electrolysis to obtain hydrogen in combination with intermittent renewable energy resources is an emerging sustainable alternative to fossil fuels. Among the available electrolyzer technologies, anion exchange membrane water electrolysis (AEMWE) has been paid much attention because of its advantageous behavior compared to other more traditional approaches such as solid oxide electrolyzer cells, and alkaline or proton exchange membrane water electrolyzers. Recently, very promising results have been obtained in the AEMWE technology. This review paper is focused on recent advances in membrane electrode assembly components, paying particular attention to the preparation methods for catalyst coated on gas diffusion layers, which has not been previously reported in the literature for this type of electrolyzers. The most successful methodologies utilized for the preparation of catalysts, including co-precipitation, electrodeposition, sol–gel, hydrothermal, chemical vapor deposition, atomic layer deposition, ion beam sputtering, and magnetron sputtering deposition techniques, have been detailed. Besides a description of these procedures, in this review, we also present a critical appraisal of the efficiency of the water electrolysis carried out with cells fitted with electrodes prepared with these procedures. Based on this analysis, a critical comparison of cell performance is carried out, and future prospects and expected developments of the AEMWE are discussed.Peer reviewe