0000000001072583
AUTHOR
C. Martino
Developmental defects induced by gadolinium ions in sea urchin embryos of phylogenetically distant species
Gadolinium (Gd) is nowadays an emergent environmental pollutant: it is a metal of the lanthanide series of the elements whose chelates are commonly employed as contrast agents for magnetic resonance imaging and subsequently released into the aquatic environment. Sea urchin embryos are highly sensitive to several kinds of stressors and able to activate different defense strategies. The aim of this study was to analyze the consequences of embryo exposure to sublethal Gd concentrations. We compared the effects of Gd on the development of four phylogenetically distant sea urchin species: two Mediterranean species, Paracentrotus lividus and Arbacia lixula, and two species living in the East coas…
Cellular and molecular bases of biomineralization in sea urchin embryos
Sea urchin embryos construct their skeleton following a precise gene-regulated time- and space-dependent programme, in concert with factors promoting cell adhesion and differentiation. The biomineral is deposited in a privileged extracellular space produced by the fused filopodia processes of the primary mesenchyme cells, the only cells producing a set of necessary matrix proteins. More than ten years ago we showed for the first time that signals from ectoderm cells promoted the expression of one of the major skeleton matrix genes by the primary mesenchyme cells. Since then, many of the crucial steps of this complex activation cascade, from ectoderm cells to embryonic spicules, have been el…
APOPTOSIS RATE IN CUMULUS CELLS AS POSSIBLE MOLECULAR BIOMARKER FOR OOCYTE COMPETENCE.
Several lines of evidence showed that apoptosis rate of cumulus cells in oocytes derived by assisted reproductive technologies could be used as an indicator of fertilizing gamete quality. Aim of the study was to investigate the effects of three different ovarian stimulation protocols on the biological and clinical outcome in hyporesponder patients. Collected data showed a higher significant rate of DNA fragmentation index (DFI) in U group (patients treated with Highly Purified human Menopausal Gonadotrophin) than in P group (treated with recombinant human Follicle Stimulating Hormone (r-hFSH) combined with recombinant human Luteinizing Hormone (r-hLH)). Both groups R (treated with r-hFSH al…
Magnesium deprivation affects development and biomineralization in the sea urchin arba-cia lixula
Skeletogenesis is a key morphogenetic event in the life of marine invertebrates. Marine calcifiers secrete their calcareous skeletons taking up ions from seawater. Marine biominerals include aragonite and calcite, the latter of which in some taxa (e.g. echinoderms, coralline algae) can have a substantial magnesium (Mg) component. Echinoderms have an extensive endoskeleton composed of high magnesian calcite and occluded matrix proteins1. As biomineralization in sea urchin larvae is sensitive to the Magnesium:Calcium ratio of sea water, we investigated the effects of magnesium deprivation on development and skeletogenesis in the Mediterranean sea urchin Arbacia lixula. Microscopic inspection …