Early handling modulates outcome of neonatal dexamethasone exposure

Synthetic glucocorticoids such as dexamethasone (DEX) are used to prevent or treat respiratory disorders in prematurely born infants. Besides the short-term benefit on lung development, numerous human and animal studies have reported adverse neurodevelopmental side effects. In contrast, maternal care is known to exert a positive influence on neurodevelopmental outcome in rodents. The aim of the current study was therefore to investigate whether neonatal handling (days 1–21), known to induce maternal care, might serve as an intervention strategy modulating the adverse effects of DEX treatment (days 1–3). For this purpose we have measured the outcome of these early-life manipulations on development as well as adult endocrine and behavioral phenotype of male rats. Maternal care was observed during the first week of life and indeed enhanced in response to handling. Eye opening was accelerated and body weight reduced in DEX-treated animals. In adulthood, we report that handling ameliorated impaired spatial learning observed in DEX treated non-handled animals in the T-maze. Additionally, handling reduced susceptibility to the impact of DEX treatment in the water maze. Although DEX treatment and handling both resulted in enhanced negative feedback of the stress-induced corticosterone response and both reduced startle reactivity, the acquisition of fear was only reduced by handling, without effect of DEX. Interestingly, handling had a beneficial effect on pre-pulse inhibition, which was diminished after DEX treatment. In conclusion, these findings indicate that handling of the neonate enhances maternal care and attenuates specific DEX-induced alterations in the adult behavioral phenotype.     

Increase in Phytase Activity and Decrease in Phytate During Germination of Four Common Legumes

Maximum phytase activity in four legume species, lentils, chick peas, broad beans and runner beans, was reached after 6 days of germination for chick peas and 8 days for the rest of them. In all legumes, the increase in phytase activity was accompanied by a concomitant decrease in phytate content. After 10 days of germination the decrease in phytate varied from 83% in broad beans up to 64% in runner beans.     

Deep-sea nematode biodiversity in the Mediterranean basin: testing for longitudinal, bathymetric and energetic gradients

The knowledge of the processes controlling the spatial distribution of species diversity is one of the main challenges of the present ecological research. Spatial patterns of benthic biodiversity in the deep sea are poorly known in comparison with other ecosystems and this limits our understanding of the mechanisms controlling the distribution and maintenance of high biodiversity in the largest ecosystems of our biosphere. Although the Mediterranean basin covers <1% of the world ocean surface, none the less it hosts >7.5% of the global biodiversity. The high biogeographic complexity and the presence of steep ecological gradients contribute in making the Mediterranean a region of very high diversity. Here we report the results of an investigation on the patterns of nematode biodiversity in the deep-Mediterranean Sea, in relation with bathymetric, longitudinal and energetic gradients. Our results indicate that benthic biodiversity in the deep-Mediterranean decreases significantly with increasing depth. Moreover, at equally deep sites, nematode diversity decreased from the western to the eastern basin and longitudinal gradients were evident when comparing sites at 4000-m depth, with 3000-m depth. The analysis of the available energy (measured as labile organic matter content of the sediments) suggests that biodiversity patterns are not controlled by the amounts of food resources, but instead bio-availability is the key factor. A more detailed analysis revealed an extremely high deep-sea beta-diversity (turnover diversity), both among sites at different depths as well as at similar depths of different longitude or within the same basin. This new finding has not only important implications on the estimates of the overall regional diversity (gamma diversity), but also suggests the presence of high biogeographic complexity in the deep benthic domain of the Mediterranean Sea.     

Nutrient and oxygen redistribution during destratification in the Elefsis Bay,an anoxic basin

Destratification in Elefsis Bay due to winter cooling, heavy water formation and mechanical mixing produces homogenous water column that is moderately stratified during the summer as a result of surface heating and reduced mechanical mixing. In the Elefsis Bay, this destratification redistributes ammonia, phosphate and silicate regenerated by the organic matter as well as oxygen from the surface. This redistribution has significant implications for nutrient cycles and organism distribution in the Bay. Reasons for the increase of the phosphate concentrations through release of P from the sediments and the conversion of nitrate to nitrogen gas in oxygen-deficient water have been confirmed. The relation between the accumulation of phosphate, silicate and ammonia are discussed.     

The pyruvate-lactate axis modulates cardiac hypertrophy and heart failure

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Usefulness of F2-isoprostanes in early prognostication after cardiac arrest: a topical review of the literature and meta-analysis of preclinical data

Abstract

Prognostication after cardiac arrest (CA) represents a challenging issue, and several biomarkers have been proposed in the attempt to predict outcome. Among these, F2-isoprostanes stand out as potential biomarkers for early prognostication, providing information on the magnitude of global oxidative injury after return of spontaneous circulation (ROSC). We performed a topical review searching PubMed and Scopus databases to identify studies evaluating the modifications of F2-isoprostanes in the early period after CA, and a meta-analysis of studies providing curves of F2-isoprostanes plasma levels seeking to describe the biomarker’s kinetics after CA. Evidence suggests that plasma levels of F2-isoprostanes increase in the early post-resuscitation period and seem well correlated with the burden of ischaemia-reperfusion injury. Our meta-analysis shows a possible increase as early as 5?minutes after ROSC, which persists at 2?hours and is attenuated at 4?hours. Clinical studies are warranted to evaluate the utility of this biomarker for prognostication purposes in CA survivors.     

Proteostasis failure and mitochondrial dysfunction leads to aneuploidy-induced senescence

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