Effect of a Very-Low-Calorie Ketogenic Diet on Circulating Myokine Levels Compared with the Effect of Bariatric Surgery or a Low-Calorie Diet in Patients with Obesity

The preservation of muscle mass and muscle function after weight loss therapy is currently a considerable challenge in the fight against obesity. Muscle mass secretes proteins called myokines that have relevant functions in the regulation of metabolism and health. This study was aimed to evaluate whether a very low-calorie ketogenic (VLCK) diet may modulate myokine levels, in addition to changes in body composition, compared to a standard, balanced low-calorie (LC) diet or bariatric surgery in patients with obesity. Body composition, ketosis, insulin sensitivity and myokines were evaluated in 79 patients with overweight/obesity after a therapy to lose weight with a VLCK diet, a LC diet or bariatric surgery. The follow-up was 6 months. The weight loss therapies induced changes in myokine levels in association with changes in body composition and biochemical parameters. The effects on circulating myokine levels compared to those at baseline were stronger after the VLCK diet than LC diet or bariatric surgery. Differences reached statistical significance for IL-8, MMP2 and irisin. In conclusion, nutritional interventions or bariatric surgery to lose weight induces changes in circulating myokine levels, being this effect potentially most notable after following a VLCK dietThis work was supported by the PronoKal Group® and grants from the Fondo de Investigacion Sanitaria, PI17/01287 research projects and CIBERobn (CB06/03/0003, CB12/03/30007, CB12/03/30002, CB06/03/0018) from the Instituto de Salud Carlos III (ISCIII)-Subdireccion General de Evaluacion y Fomento de la Investigación; Fondo Europeo de Desarrollo Regional (FEDER) and the Health Department of the Government of Navarra (48/2009), Spain and Linea Especial “Nutrition, Obesity and Health” (University of Navarra LE/97). Ana B Crujeiras is funded by a research contract “Miguel Servet” (CP17/00088) from the ISCIII, co-financed by the European Regional Development Fund (FEDER)S

Evaluation of contingency plans in the care of patients in intensive care units in the COVID-19 pandemic

La expansión de las áreas de cuidados de intensivos ha sido una de las medidas más significativas en esa obligada adaptación a la evolución de las distintas fases de la pandemia por la COVID-19. El objetivo es evaluar el despliegue de los planes de contingencia en la atención a pacientes ingresados en Unidades de Cuidados Intensivos (UCI) durante el periodo del 19 de marzo al 20 de abril de 2020, en un hospital público, referencia para 300.000 habitantes, perteneciente al Servicio Galego de Saúde.Axencia Galega de Innovación (GAIN, Xunta de Galicia), cofinanciado con fondos FEDER (Unión Europea, «Una manera de hacer Europa» | Ref. IN845D-2020/0

A ubiquitous gammaproteobacterial clade dominates expression of sulfur oxidation genes across the mesopelagic ocean

21 pages, 6 figures, supplementary information https://doi.org/10.1038/s41564-023-01374-2.-- Data availability: The sequence data generated in this study have been deposited in the EMBL Nucleotide Sequence Database (ENA) database under Bioproject PRJEB35712 (metagenomic and metatranscriptomic raw reads, metagenomic and metatranscriptomic assemblies, metagenomic assembled genomes and single-cell amplified genomes) and in the NCBI Sequence Read Archive (SRA) under Bioproject PRJNA593264 (16S rRNA amplicon reads).-- Code availability: Scripts available at Zenodo (https://doi.org/10.5281/zenodo.7721930.2023)The deep ocean (>200 m depth) is the largest habitat on Earth. Recent evidence suggests sulfur oxidation could be a major energy source for deep ocean microbes. However, the global relevance and the identity of the major players in sulfur oxidation in the oxygenated deep-water column remain elusive. Here we combined single-cell genomics, community metagenomics, metatranscriptomics and single-cell activity measurements on samples collected beneath the Ross Ice Shelf in Antarctica to characterize a ubiquitous mixotrophic bacterial group (UBA868) that dominates expression of RuBisCO genes and of key sulfur oxidation genes. Further analyses of the gene libraries from the ‘Tara Oceans’ and ‘Malaspina’ expeditions confirmed the ubiquitous distribution and global relevance of this enigmatic group in the expression of sulfur oxidation and dissolved inorganic carbon fixation genes across the global mesopelagic ocean. Our study also underscores the unrecognized importance of mixotrophic microbes in the biogeochemical cycles of the deep oceanThis research was facilitated by the New Zealand Antarctic Research Institute (NZARI)-funded Aotearoa New Zealand Ross Ice Shelf Program. Samples for MICRO-CARD-FISH were collected on several research cruises led by M. Simon (Sonne 248 cruise), B. Quéguiner and I. Obernosterer (MobyDick) and L. J. A. Gerringa (Geotraces-1). F.B. was supported by the Austrian Science Fund (FWF) projects OCEANIDES (P34304-B), ENIGMA (TAI534), EXEBIO (P35248) and OCEANBIOPLAST (P35619-B). G.J.H. was supported by the FWF project ARTEMIS (P28781-B21) and I486-B09 and by the ERC under the European Community’s 7th Framework Programme (FP7/2007-2013)/ERC grant agreement no. 268595 (MEDEA project). R.L. was supported by INTERACTOMICS, CTM2015-69936-P, and J.M.G. by project PID2019-110011RB-C32 (Spanish Ministry of Science and Innovation, Spanish State Research Agency, doi: 10.13039/501100011033)With the institutional support of the ‘Severo Ochoa Centre of Excellence’ accreditation (CEX2019-000928-S)Peer reviewe

Transient Changes in Bacterioplankton Communities Induced by the Submarine Volcanic Eruption of El Hierro (Canary Islands)

Postprint4,411

NKG2D expression in CD4+ T lymphocytes as a marker of senescence in the aged immune system

Human aging is characterized by changes in the immune system which have a profound impact on the T-cell compartment. These changes are more frequently found in CD8+ T cells, and there are not well-defined markers of differentiation in the CD4+ subset. Typical features of cell immunosenescence are characteristics of pathologies in which the aberrant expression of NKG2D in CD4+ T cells has been described. To evaluate a possible age-related expression of NKG2D in CD4+ T cells, we compared their percentage in peripheral blood from 100 elderly and 50 young adults. The median percentage of CD4+ NKG2D+ in elders was 5.3% (interquartile range (IR): 8.74%) versus 1.4% (IR: 1.7%) in young subjects (p < 0.3 × 10−10). CD28 expression distinguished two subsets of CD4+ NKG2D+ cells with distinct functional properties and differentiation status. CD28+ cells showed an immature phenotype associated with high frequencies of CD45RA and CD31. However, most of the NKG2D+ cells belonged to the CD28null compartment and shared their phenotypical properties. NKG2D+ cells represented a more advanced stage of maturation and exhibited greater response to CMV (5.3 ± 3.1% versus 3.4 ± 2%, p = 0.037), higher production of IFN-γ (40.56 ± 13.7% versus 24 ± 8.8%, p = 0.015), lower activation threshold and reduced TREC content. Moreover, the frequency of the CD4+ NKG2D+ subset was clearly related to the status of the T cells. Higher frequencies of the NKG2D+ subset were accompanied with a gradual decrease of NAIVE and central memory cells, but also with a higher level of more differentiated subsets of CD4+ T cells. In conclusion, CD4+ NKG2D+ represent a subset of highly differentiated T cells which characterizes the senescence of the immune system

Synthesis and characterization of nanohybrid materials based on block copolymers and clays

Η ανάμειξη ανόργανων υλικών με πολυμερή οδηγεί στην παρασκευή σύνθετων υλικών τα οποία παρουσιάζουν βελτιωμένες ιδιότητες σε σχέση με τα αρχικά συστατικά. Μια σημαντική κατηγορία τέτοιων σύνθετων υλικών αποτελούν τα νανοσύνθετα υλικά στα οποία το ανόργανο πρόσθετο έχει τουλάχιστον μια διάσταση της τάξης του νανομέτρου. Σε αυτήν την κατηγορία ανήκουν τα υβρίδια που προκύπτουν από την ανάμειξη πολυμερών με πολυστρωματικούς πυριτιούχους πηλούς. Τα υλικά αυτά εμφανίζουν ανάλογα με τη δομή του σύνθετου υλικού υψηλότερη θερμική αντοχή και καλύτερες μηχανικές ιδιότητες ενώ συγχρόνως διατηρούν πλεονεκτήματα των αρχικών πολυμερών, όπως η διαφάνεια ή η ευκολία στην κατεργασία . Αντικείμενο της παρούσας εργασίας είναι η σύνθεση και η μελέτη των αλληλεπιδράσεων και των ιδιοτήτων νανοσύνθετων υλικών που αποτελούνται από πολυστρωματικούς πυριτιούχους πηλούς και δισυσταδικά συμπολυμερή πολυαιθυλενοξειδίου-πολυστυρενίου (PEO-b-PS). Ο πηλός που χρησιμοποιήθηκε ήταν ο φυσικός υδρόφιλος μοντμοριλλονίτης νατρίου (Na+) ενώ τα συμπολυμερή συντέθηκαν στο εργαστήριο με τη χρήση ελεγχόμενου ριζικού πολυμερισμού. Από την βιβλιογραφία είναι γνωστό ότι το ομοπολυμερές του PEO έχει την δυνατότητα παρεμβολής ανάμεσα στα στρώματα του μοντμοριλλονίτη Νa+καθώς είναι υδρόφιλο μόριο και επομένως οι αλληλεπιδράσεις του με την επιφάνεια του πηλού είναι ευνοϊκές. Αντίθετα το ομοπολυμερές του PS είναι υδρόφοβο με αποτέλεσμα οι αλληλεπιδράσεις του με τον πηλό να είναι μη ευνοϊκές και επομένως δεν δίνει δομές παρεμβολής αλλά φασικά διαχωρισμένες δομές. Σκοπός της εργασίας αυτής είναι να μελετήσει τι συμβαίνει στην περίπτωση των αμφίφιλων συμπολυμερών PEO-b-PS. Ποιες είναι οι συνολικές αλληλεπιδράσεις των συμπολυμερών με τον φυσικό υδρόφιλο μοντμοριλλονίτη και ποια η δομή των νανοσύνθετων υλικών που προκύπτουν. Ειδικότερα εξετάστηκε η επίδραση του μοριακού βάρους και της σύστασης των συμπολυμερών στην τελική δομή των νανοσύνθετων υλικών. Για τον σκοπό αυτό αρχικά συντέθηκαν επτά συμπολυμερή PEO-b-PS με ελεγχόμενο ριζικό πολυμερισμό μεταφοράς ατόμου (Atom Transfer Radical Polymerization, ATRP) και στην συνέχεια τα πολυμερή χαρακτηρίσθηκαν ως προς το μοριακό βάρος, την κατανομή μοριακών βαρών και την σύστασή τους. Μελετήθηκαν επίσης οι θερμικές ιδιότητες των πολυμερών και η θερμοδυναμική τους κατάσταση. Για την παρασκευή των νανοσύνθετων υλικών χρησιμοποιήθηκε η μέθοδος παρεμβολής τήγματος πολυμερούς. Στην συνέχεια χρησιμοποιήθηκε περίθλαση ακτίνων Χ για την μελέτη της δομής τους και για την εύρεση της διαστρωματικής τους απόστασης. Βρέθηκε ότι η δομή που εμφανίζουν τα νανοϋβρίδια είναι δομή παρεμβολής με διαστρωματικές αποστάσεις που μοιάζουν με αυτές που εμφανίζει το ομοπολυμερές PEO όταν αναμειγνύεται με το ίδιο ανόργανο υλικό και φαίνεται ότι ο λόγος που καθορίζει την τελική δομή σε όλες τις περιπτώσεις είναι η σύσταση PEO ως προς Na+. Για να ερευνηθεί ο ρόλος που παίζει η συστάδα του PS σε όλη την διαδικασία μελετήθηκαν οι αλληλεπιδράσεις που αναπτύσσονται ανάμεσα στις συστάδες του συμπολυμερούς και της ανόργανης επιφάνειας με την βοήθεια φασματοσκοπίας υπερύθρου. Τέλος, μελετήθηκε ο φθορισμός της συστάδας του πολυστυρενίου και η επίδραση που έχει σε αυτόν η θέση του πολυστυρενίου στο σύστημα. Η τεχνική που χρησιμοποιήθηκε για τον σκοπό αυτό είναι η φθορισμομετρία η οποία έδειξε ότι ο εγγενής φθορισμός του πολυστυρενίου χάνεται όταν αυτό βρίσκεται περιορισμένο μεταξύ των στρωμάτων του ανόργανου υλικού. Στην περίπτωση των νανοσύνθετων υλικών Na+/PEO-b-PS ο φθορισμός του PS είναι μετρήσιμος, γεγονός που αποδεικνύει ότι η συστάδα του PS βρίσκεται έξω από τις γαλαρίες.Mixing polymers with inorganic materials leads to the synthesis of composites, which have improved properties with respect to the original materials. An important category among them, are the nanohybrids in which the inorganic component has at least one dimension at the nanometer scale. This category includes hybrids that are formed by mixing polymers with layered silicate clays. Such materials exhibit (depending on their structure) high thermal resistance and improved mechanical properties, whereas they retain the advantages of the initial polymers, such as the transparency or the easy processability. The purpose of the present project is the synthesis and the study of the interactions and the properties of nanocomposite materials which consist of layered silicate clays and poly(ethylene oxide)-b-poly(styrene) (PEO-b-PS) diblock copolymers. The clay used is a natural hydrophilic sodium montmorillonite (Na+) whereas the copolymers were synthesized in the lab, in the framework of this work, utilizing controlled radical polymerization. It is well known from the literature that the PEO homopolymer has the ability to intercalate between the layers of the clay, as it is hydrophilic molecule, therefore has favorable interactions with the surface of the clay. On the other hand, the PS homopolymer is hydrophobic molecule and has unfavorable interactions with the clay, leading to phase separated structures. This study is focalized in the case of PEO-b-PS amphiphilic copolymers. The total interactions of the copolymers with the natural montmorillonite as well as the structure of the resulted nanocomposite materials are investigated. Especially, the influence of the molecular weight and the concentration of the copolymers to the final structure of the nanocomposite materials is examined in detail. Seven PEO-b-PS copolymers with varying molecular weight and composition were synthesized utilizing controlled Atom Transfer Radical Polymerization (ATRP). Their molecular weight and their polydispersity were evaluated with Size Exclusion Chromatography (SEC) whereas their composition was measured with 1H Nuclear Magnetic Resonance (1H NMR). The thermal properties and the thermodynamic condition of the polymers were also studied with Differential Scanning Calorimetry (DSC) and Small Angle X-ray Scattering (SAXS) respectively. For the preparation of the nanocomposite materials, the polymer melt intercalation method was used and hybrids with composition that varied from pure polymer to pure clay were synthesized. Following the synthesis, X-ray diffraction (XRD) was utilized to study the structure and to determine the interlayer distance. It was found that all nanohybrids have intercalated structure with interlayer distances that are similar to the ones that correspond to the respective of PEO homopolymer when it is mixed with the same inorganic material. There is, thus, a strong indication that in every case the final structure is determined by just the Na+/PEO ratio in the copolymer hybrids. In order to investigate the role of the PS block in the system, the interactions between the blocks of the copolymer and the inorganic surface were studied by infrared spectroscopy (FTIR). Finally, the fluorescence of the PS block as well as the way it is affected by whether the polystyrene is intercalated or not was studied. It was proved that the intrinsic fluorescence of PS is vanished when it is intercalated between the inorganic layers. In the case of the Na+/PEO-b-PS nanocomposites the PS fluorescence is measurable, evidencing that the PS block is outside of the inorganic galleries and only the PEO block of the copolymer intercalates