Semantically Derived Geometric Constraints for {MVS} Reconstruction of Textureless Areas

Conventional multi-view stereo (MVS) approaches based on photo-consistency measures are generally robust, yet often fail in calculating valid depth pixel estimates in low textured areas of the scene. In this study, a novel approach is proposed to tackle this challenge by leveraging semantic priors into a PatchMatch-based MVS in order to increase confidence and support depth and normal map estimation. Semantic class labels on image pixels are used to impose class-specific geometric constraints during multiview stereo, optimising the depth estimation on weakly supported, textureless areas, commonly present in urban scenarios of building facades, indoor scenes, or aerial datasets. Detecting dominant shapes, e.g., planes, with RANSAC, an adjusted cost function is introduced that combines and weighs both photometric and semantic scores propagating, thus, more accurate depth estimates. Being adaptive, it fills in apparent information gaps and smoothing local roughness in problematic regions while at the same time preserves important details. Experiments on benchmark and custom datasets demonstrate the effectiveness of the presented approach

Propolis Extracts Inhibit UV-Induced Photodamage in Human Experimental In Vitro Skin Models

The aim of this study was to assess the antioxidant, photoprotective, and antiaging effects of Greek propolis. Propolis was subjected to n-heptane or methanol extraction. Total phenolic/flavonoid content and antioxidant potential were determined in the extracts. Promising extracts were evaluated for their cytoprotective properties using human immortalized keratinocyte (HaCaT) or reconstituted human skin tissue following exposure to UVB. Assessment of cytotoxicity, DNA damage, oxidative status, and gene/protein expression levels of various matrix metalloproteinases (MMPs) were performed. The propolis methanolic fractions exhibited higher total phenolic and flavonoid contents and significant in vitro antioxidant activity. Incubation of HaCaT cells with certain methanolic extracts significantly decreased the formation of DNA strand breaks following exposure to UVB and attenuated UVB-induced decrease in cell viability. The extracts had no remarkable effect on the total antioxidant status, but significantly lowered total protein carbonyl content used as a marker for protein oxidation in HaCaT cells. MMP-1, -3, -7, and -9, monitored as endpoints of antiaging efficacy, were significantly reduced by propolis following UVB exposure in a model of reconstituted skin tissue. In conclusion, propolis protects against the oxidative and photodamaging effects of UVB and could be further explored as a promising agent for developing natural antiaging strategies

New insights into hydrothermal vent processes in the unique shallow-submarine arc-volcano, Kolumbo (Santorini), Greece

We report on integrated geomorphological, mineralogical, geochemical and biological investigations of the hydrothermal vent field located on the floor of the density-stratified acidic (pH , 5) crater of the Kolumbo shallow-submarine arc-volcano, near Santorini. Kolumbo features rare geodynamic setting at convergent boundaries, where arc-volcanism and seafloor hydrothermal activity are occurring in thinned continental crust. Special focus is given to unique enrichments of polymetallic spires in Sb and Tl (6Hg, As, Au, Ag, Zn) indicating a new hybrid seafloor analogue of epithermal-to-volcanic-hosted-massive-sulphide deposits. Iron microbial-mat analyses reveal dominating ferrihydrite-type phases, and high-proportion of microbial sequences akin to "Nitrosopumilus maritimus", a mesophilic Thaumarchaeota strain capable of chemoautotrophic growth on hydrothermal ammonia and CO2. Our findings highlight that acidic shallow-submarine hydrothermal vents nourish marine ecosystems in which nitrifying Archaea are important and suggest ferrihydrite-type Fe31-(hydrated)-oxyhydroxides in associated low-temperature iron mats are formed by anaerobic Fe21-oxidation, dependent on microbially produced nitrate

Human model of primary carnitine deficiency cardiomyopathy reveals ferroptosis as a novel mechanism

Primary carnitine deficiency (PCD) is an autosomal recessive monogenic disorder caused by mutations in SLC22A5. This gene encodes for OCTN2, which transports the essential metabolite carnitine into the cell. PCD patients suffer from muscular weakness and dilated cardiomyopathy. Two OCTN2-defective human induced pluripotent stem cell lines were generated, carrying a full OCTN2 knockout and a homozygous OCTN2 (N32S) loss-of-function mutation. OCTN2-defective genotypes showed lower force development and resting length in engineered heart tissue format compared with isogenic control. Force was sensitive to fatty acid-based media and associated with lipid accumulation, mitochondrial alteration, higher glucose uptake, and metabolic remodeling, replicating findings in animal models. The concordant results of OCTN2 (N32S) and -knockout emphasizes the relevance of OCTN2 for these findings. Importantly, genome-wide analysis and pharmacological inhibitor experiments identified ferroptosis, an iron- and lipid-dependent cell death pathway associated with fibroblast activation as a novel PCD cardiomyopathy disease mechanism

Abstracts from the 8th International Conference on cGMP Generators, Effectors and Therapeutic Implications

This work was supported by a restricted research grant of Bayer AG

Chemical analysis of selected natural dyestuffs: study of their potentional biological activity

The knowledge of the isolation and identification of natural organic dyestuffs constitutes a very important element of the natural and cultural heritage of the Mediterranean. The identification of the natural organic dyestuffs that have been used in artworks of cultural heritage is considered essential for the contribution in the certification of the work’s authenticity, for the work’s correct maintenance and for the determination of the time period that the work was created. Finally, the study of their potential biological activity offers greater interest in these dyes.The aim of the present doctoral thesis was the collection and the chemical analysis of natural organic colourants, the identification of the structure of the isolated components as well as the study of their biological activity.In the first part, dyestuffs of historical interest were studied. Thus, Cotinus coggygria Scop., Dactylopius coccus Costa, and Caesalpinia sappan L were studied. 11 colouring compounds were isolated from C. coggygria, 7 of which are reported for the first time as components of C. coggygria. 4 colouring components were isolated from C. sappan. 7 colouring components were isolated from Dactylopius coccus. 4 of them are new natural products, 3 of which are known as dcIII, dcIV, dcVII.In the second part, natural dyes of microbial origin were studied. Secondary metabolites of Malasseziz furfur strains were isolated when L-tryptophan was used as the single nitrogen source in the culture medium. The production of indole derivatives using HPLC from multiple and independent extracts of M. furfur strains that come from different skin regions and diseases, as well as the statistical analysis for the comparison of indole derivatives that were isolated by various strains of M. furfur, was investigated. Then, indirubin was isolated and quantified in various M. furfur strains. 8 metabolites were isolated, 2 of which were isolated for first time. It was also proved that:• The production of indole metabolites is regulated by factors related with the origin of each strain.• The indole derivatives were produced at statistically significant quantities by all M. furfur strains isolated from pathogenic skin compared to strains isolated from healthy skin. • The quantity of metabolites is statistically connected with the severity of the illness: Seborrhoeic dermatitis > pityriasis versicolor> dandruff >healthy.• Indolo[3,2-b]carbazole and indirubin are described for the first time as M. furfur metabolites. Both of them are potent ligands of the aryl hydrocarbon receptor (AhR).• The extractions of M. furfur are AhR activators

Signalling mechanisms that are involved in the physiological responses of cardiac cells to pH changes

The aim of the present study was the investigation of the effects of extracellular pH changes and conditions that are associated with alterations of intracellular pH, like the effect of growth factors and oxidative stress, in the activation of the MAPK signalling pathways in heart experimental models. The biological material used included the isolated perfused heart of the amphibian Rana ndibunda, the H9c2 rat cardiac myoblasts and the isolated neonatal rat ventricular myocytes. For the purposes of the study biochemical, immunological, histochemical, molecular and radiochemical methods were used. The results showed that alkalosis, acidosis and the system of xanthine/xanthine oxidase activate p38-MAPK in the amphibian heart, the last through the production of superoxide anion The alkalosisinduced p38-MAPK activation depends on the function of NHE1 and Na⁺/K⁺-ATPase, whereas both this stimulus and the xanthine/xanthine oxidase system increase the phosphorylation levels of two proteins that exist downstream of p38-MAPK, MAPKAPK2 and HSP27. From the experiments in H9c2 cells it was found that extracellular alkalosis induces an increase in intracellular pH which depends on both NHE1 and ERKs Incubation of cells with a medium of pH value pH 8,5 activates p38-MAPK, JNKs and ERKs which, as it was shown in the case of the amphibian, it depends on NHE1. Activation of ERKs as well as of the kinase PKB is also observed in isolated neonatal rat ventricular cardiomyocytes during the action of growth factors and peptide hormones. In H9c2 cells and during alkalosis (pH 8,5), JNKs phosphorylate the transcription factor AP-1 subunit c-Jun and the antiapoptotic protein Bcl-2, results suggesting that these kinases control gene expression and cell survival. On the other hand, ERKs and p38-MAPK converge at the level of the kinase MSK1 implying that through it, they mutually regulate some of the physiological responses of cells under alkaline conditions. Finally, it seems that all these reactions contribute to H9c2 cell survival since inhibition of all three MAPKs studied increases massively the number of dead cells.Σκοπός της παρούσας εργασίας ήταν η διερεύνηση των επιπτώσεων των μεταβολών του εξωκυτταρικού pH και συνθηκών που σχετίζονται με μεταβολές του ενδοκυτταρικού pH, όπως είναι η επίδραση αυξητικών παραγόντων και οξειδωτικού στρες, στην ενεργοποίηση των σηματοδοτικών μονοπατιών των MAPKs σε πειραματικά μοντέλα καρδιακών κυττάρων. Τα βιολογικά υλικά που χρησιμοποιήθηκαν ήταν η απομονωμένη εμποτισμένη καρδιά του αμφιβίου Rana ridibunda, οι H9c2 καρδιακοί μυοβλάστες αρουραίου και τα απομονωμένα καρδιακά κοιλιακά μυοκύτταρα νεογνού αρουραίου. Για τους σκοπούς της μελέτης χρησιμοποιήθηκαν βιοχημικές, ανοσολογικές, ιστοχημικές, μοριακές και ραδιοχημικές μέθοδοι. Τα αποτελέσματα έδειξαν ότι η αλκάλωση, η οξέωση και το σύστημα της ξανθίνης/οξειδάσης της ξανθίνης ενεργοποιούν την p38-ΜΑΡΚ στην καρδιά του αμφιβίου, το τελευταίο μέσω της παραγωγής του ανιόντος του υπεροξειδίου. Η επαγόμενη από την αλκάλωση ενεργοποίηση της p38-ΜΑΡΚ εξαρτάται από τη λειτουργία του ΝΗΕ1 και της Νa⁺/Κ⁺-ΑΤΡάσης, ενώ τόσο αυτό το ερέθισμα όσο και το σύστημα της ξανθίνης/οξειδάσης της ξανθίνης αυξάνουν τα επίπεδα φωσφορυλίωσης δύο πρωτεϊνών που βρίσκονται καταρροϊκά της p38-ΜΑΡΚ, της ΜΑΡΚΑΡΚ2 και της HSP27. Από πειράματα στα H9c2 κύτταρα βρέθηκε ότι η εξωκυτταρική αλκάλωση προκαλεί αύξηση του ενδοκυτταρικού pH και αυτό εξαρτάται τόσο από τον ΝΗΕ1 όσο και από τις ERKs. Η επώαση των κυττάρων με μέσο τιμής pH 8,5 ενεργοποιεί την p38-ΜΑΡΚ, τις JNKs και τις ERKs και, όπως στην περίπτωση του αμφιβίου, έτσι και στα H9c2 κύτταρα αυτό εξαρτάται από τον ΝΗΕ1. Ενεργοποίηση των ERKs αλλά και της κινάσης ΡΚΒ παρατηρείται επίσης και σε απομονωμένα καρδιακά κοιλιακά μυοκύτταρα νεογνού αρουραίου κατά την επίδραση αυξητικών παραγόντων και πεπτιδικών ορμονών. Στα H9c2 κύτταρα, και σε συνθήκες αλκάλωσης (pH 8,5), οι JNKs φωσφορυλιώνουν την υπομονάδα του μεταγραφικού παράγοντα ΑΡ-1 c-Jun και την αντιαποπτωτική πρωτεΐνη Bcl-2, γεγονός που υποδεικνύει ότι οι κινάσες αυτές ελέγχουν τη γονιδιακή έκφραση και την επιβίωση των κυττάρων. Από την άλλη πλευρά, οι ERKs και η p38-ΜΑΡΚ συγκλίνουν στο επίπεδο της κινάσης MSK-1 υποδεικνύοντας ότι μέσω αυτής πιθανώς ρυθμίζουν από κοινού κάποιες από τις φυσιολογικές αποκρίσεις των κυττάρων σε αυτές τις συνθήκες. Τελικά, όλες αυτές οι αντιδράσεις φαίνεται ότι συμβάλλουν στην επιβίωση των H9c2 κυττάρων σε συνθήκες αλκάλωσης αφού η αναστολή και των τριών MAPKs που εξετάστηκαν αυξάνει μαζικά τον αριθμό των νεκρών κυττάρων

Multi-view stereo with semantic priors

Patch-based stereo is nowadays a commonly used image-based technique for dense 3D reconstruction in large scale multi-view applications. The typical steps of such a pipeline can be summarized in stereo pair selection, depth map computation, depth map refinement and, finally, fusion in order to generate a complete and accurate representation of the scene in 3D. In this study, we aim to support the standard dense 3D reconstruction of scenes as implemented in the open source library OpenMVS by using semantic priors. To this end, during the depth map fusion step, along with the depth consistency check between depth maps of neighbouring views referring to the same part of the 3D scene, we impose extra semantic constraints in order to remove possible errors and selectively obtain segmented point clouds per label, boosting automation towards this direction. In order to reassure semantic coherence between neighbouring views, additional semantic criterions can be considered, aiming to eliminate mismatches of pixels belonging in different classes