Characterization of carbonate fraction of the Atlantic bluefin tuna fin spine bone matrix for stable isotope analysis.

The mineral component of fish otoliths (ear bones), which is aragonitic calcium carbonate (CaCO3), makes this structure the preferred sample choice for measuring biological carbon and oxygen-stable isotopes in order to address fundamental questions in fish ecology and fisheries science. The main drawback is that the removal of otoliths requires sacrificing the specimen, which is particularly impractical for endangered and commercially valuable species such as Atlantic bluefin tuna (Thunnus thynnus) (ABFT). This study explores the suitability of using the first dorsal fin spine bone of ABFT as a non-lethal alternative to otolith analysis or as a complementary hard structure. The fin spines of freshly caught ABFT were collected to identify carbonate ions within the mineral matrix (i.e., hydroxyapatite) and to determine the nature of the carbonate substitution within the crystal lattice, knowledge which is crucial for correct measurement and ecological interpretation of oxygen and carbon stable isotopes of carbonates. Fin spine sections were analyzed via X-ray Photoelectron Spectroscopy (XPS), Raman Spectroscopy, and Fourier Transform InfraRed (FTIR). The XPS survey analysis showed signals of Ca, O, and P (three compositional elements that comprise hydroxyapatite). The Raman and FTIR techniques showed evidence of carbonate ions within the hydroxyapatite matrix, with the IR spectra being the most powerful for identifying the type B carbonate substitution as shown by the carbonate band in the v 2 CO3 2- domain at ∼872 cm-1. The results of this study confirmed the presence of carbonate ions within the mineral matrix of the fin spine bone of ABFT, showing the feasibility of using this calcified structure for analysis of stable isotopes. Overall, our findings will facilitate new approaches to safeguarding commercially valuable and endangered/protected fish species and will open new research avenues to improve fisheries management and species conservation strategies.

Detection of non-coloured anthocyanin-flavanol derivatives in Rioja aged red wines by liquid chromatography-mass spectrometry.

Anthocyanins, responsible for wine colour, are involved in many reactions during wine ageing. Anthocyanin-flavanol associations give rise to derivatives in flavylium form that provide blue hues, but also derivatives that do not directly influence wine colour. These colourless derivatives remain mostly unknown but their roles during wine ageing are important for controlling wine quality. Colourless anthocyanin-flavanol derivatives formed during wine ageing have been studied in three aged red wines from Rioja using a combined method with Column Chromatography (CC) and High Performance Liquid Chromatography with Diode Array and Mass Spectrometric detections (HPLC-DADMS). Twenty-six compounds have been detected: 17 dimers with the anthocyanin in flavene form with possible anthocyanin-flavanol (type 1) and flavanol-anthocyanin (type 2) structures, and 9 with an A-type bicyclic anthocyanin-flavanol structure (type 3). Although some of malvidin derivatives have been previously reported, this is the first time that these derivatives (including different isomers) have also been detected for delphinidin, petunidin and peonidin.

Time-dependent release of growth factors from implant surfaces treated with plasma rich in growth factors.

Plasma rich in growth factors (PRGFs) technology is an autologous platelet-rich plasma approach that provides a pool of growth factors and cytokines that have been shown to increase tissue regeneration and accelerate dental implant osseointegration. In this framework, the spatiotemporal release of growth factors and the establishment of a provisional fibrin matrix are likely to be key aspects governing the stimulation of the early phases of tissue regeneration around implants. We investigated the kinetics of growth factor release at implant surfaces functionalized either with PRGFs or platelet-poor plasma and correlated the results obtained with the morphology of the resulting interfaces. Our main finding is that activation and clot formation favors longer residence times of the growth factors at the interfaces studied, probably due to their retention in the adsorbed fibrin matrix. The concentration of the platelet-derived growth factors above the interfaces becomes negligible after 2-4 days and is significantly higher in the case of activated interfaces than in the case of nonactivated ones, whereas that of the plasmatic hepatocyte growth factor is independent of platelet concentration and activation, and remains significant for up to 9 days. Platelet-rich plasma preparations should be activated to permit growth factor release and thereby facilitate implant surface osseointegration.