Diving as a Scientist: Training, Recognition, Occupation - The “Science Diver” Project

Conducting scientific work underwater is a challenging endeavor. From collecting samples to protecting underwater cultural heritage sites scientific divers need to address issues concerning scientific methodology, diving safety, professional acknowledgement, training, legal implications etc. All of these matters are handled in different ways depending on factors like region, organizations involved, legal framework, diving philosophy etc. producing a diverse framework on scientific diving as a distinct type of underwater work. The ScienceDIVER project’s main objective is to study and analyze this fragmented landscape, in order to provide insight and suggestions towards a commonly accepted framework that will promote scientific diving as a means of forwarding knowledge both within the scientific community and its interaction with the public

Sustained activation of the unfolded protein response induces cell death in Fuchs' endothelial corneal dystrophy

Purpose: The unfolded protein response (UPR) is believed to play a role in the pathogenesis of Fuchs' endothelial corneal dystrophy (FECD). The purpose of this study was to investigate whether unfolded proteins accumulate in the corneal endothelium in FECD and if they are involved in triggering cell death. Methods: Descemet's membranes with corneal endothelial cells (CECs) were obtained during keratoplasty, and expression of aggresomes, type 1 collagen, fibronectin, and agrin was evaluated. Endoplasmic reticulum (ER) stress of immortalized human CECs from non-FECD subjects and from FECD patients (iHCEC and iFECD, respectively) were evaluated. The effect of MG132-mediated aggresome formation on the UPR and intrinsic pathway and the effect of mitochondrial damage on UPR were also examined. The effect of CHOP knockdown on the ER stress–mediated intrinsic pathway was also evaluated. Results: Aggresome formation was higher in iFECD than in iHCEC and was colocalized with type 1 collagen, fibronectin, and agrin. GRP78, phosphorylated IRE1, PERK, and CHOP showed higher activation in iFECD than in iHCEC. MG132-mediated aggresome formation upregulated ER stress sensors, the mitochondrial membrane potential drop, cytochrome c release to the cytoplasm, and activation of caspase-9 and -3. By contrast, staurosporine-mediated mitochondrial damage did not induce ER stress. Knockdown of CHOP attenuated the ER stress-induced cleavage of caspase-9, which is caused by intrinsic pathway activation. Conclusions: Excessive synthesis of extracellular matrix proteins induced unfolded protein accumulation in FECD. Prolonged ER stress–mediated cell death, occurring via the intrinsic apoptotic signaling pathway, therefore might be associated with the pathogenesis of FECD

Preventive Effects of Omega-3 and Omega-6 Fatty Acids on Peroxide Mediated Oxidative Stress Responses in Primary Human Trabecular Meshwork Cells

Pathologic processes in glaucoma include increased apoptosis, accumulation of extracellular material in the trabecular meshwork and optic nerve, condensations of the cytoskeleton and precocious cellular senescence. Oxidative stress was shown to generate these alterations in primary ocular cells. Fatty acids omega-3 and -6 are alleged to constitute a prophylaxis against these deleterious effects. Here, we tested actual preventive effects omega-3 and -6 against peroxide induced stress responses in primary human trabecular meshwork cells. Changes of mitochondrial activity, proliferation, heat shock proteins, extracellular matrix components, and inflammatory markers were evaluated. Alterations of the cytoskeleton were evaluated by phalloidin labeling. Here we report a repressive effect of omega-6 on metabolic activity and proliferation, which was not detected for omega-3. Both agents were able to prevent the anti-proliferative effect of H2O2, but only omega-3 prevented metabolic repression. Expression of heat shock protein 27 was unaltered by both fatty acids, whereas heat shock protein 90 was significantly induced by both. Omega-6 increased fibronectin and connective tissue growth factor synthesis, as well as the amount of secreted fibronectin. Omega-3, instead, induced plasminogen activator inhibitor 1 synthesis. H2O2 further increased fibronectin production in omega-6 supplemented cells, which was not the case in omega-3 treated cells. H2O2 stimulation of plasminogen activator inhibitor 1 and connective tissue growth factor was repressed by both fatty acids. Both fatty acids appeared to abolish H2O2 mediated stimulation of nuclear factor κB and IL-6, but not IL-1α and IL-8. H2O2 induced formation of cross-linked actin networks and stress fibers, which was reduced by preemptive application of omega-3. Omega-6, in contrast, had no protective effect on that, and even seemed to promote condensation. Based on the observed side effects of omega-6, omega-3 appears to be the more beneficial fatty acid in respect of prophylactic intake for prevention of a glaucomatous disease

Effect of trinucleotide repeat expansion on the expression of TCF4 mRNA in Fuchs' endothelial corneal dystrophy

Purpose: CTG trinucleotide repeat (TNR) expansion is frequently found in transcription factor 4 (TCF4) in Fuchs' endothelial corneal dystrophy (FECD), though the effect of TNR expansion on FECD pathophysiology remains unclear. The purpose of this study was to evaluate the effect of TNR expansion on TCF4 expression in corneal endothelium of patients with FECD. Methods: Peripheral blood DNA and Descemet membrane with corneal endothelium were obtained from 203 German patients with FECD. The CTG TNR repeat length in TCF4 was determined by short tandem repeat (STR) assays and Southern blotting using genomic DNA. Genotyping of rs613872 in TCF4 was performed by PCR. TCF4 mRNA levels in corneal endothelium were evaluated by quantitative PCR using three different probes. Control corneal endothelial samples were obtained from 35 non-FECD subjects. Results: The STR assay and Southern blotting showed that 162 of the 203 patients with FECD (80%) harbored CTG trinucleotide repeat lengths larger than 50. Quantitative PCR using all three probes demonstrated that TCF4 mRNA is significantly upregulated in the corneal endothelium of patients with FECD, regardless of the presence of TNR expansion. However, the length of the TNR tended to show a positive correlation with TCF4 expression level. No correlation was shown between the genotype of TCF4 SNP, rs613872, and the level of TCF4 expression. Conclusions: Our findings showed that TCF4 mRNA is upregulated in the corneal endothelium of patients with FECD. Further studies on the effects of TCF4 upregulation on corneal endothelial cell function will aid in understanding the pathophysiology of FECD

Protection and management of underwater archaeological sites in Greece: theoretical and methodological approach

The development in the fields of maritime archaeology and management of cultural heritage, yields a creative academic frame, in which several dynamic tendencies have been gaining strength these past few years. International conventions and conferences seek for common prospective in theoretical approaches, while national strategies develop to implement maritime cultural heritage management in various cultural contexts. In Greece, although it seems a paradox, for a long period these tendencies had not kicked in. However, it looks like the right conditions have been formed for the development of this line of thought. Maritime archaeology gains momentum and a variety of developing underwater projects combined with the country’s rich maritime archaeological record provide the ideal environment for the production of this kind of archaeological knowledge. Considering the social and financial advantages of such a development, one can feel certain to achieve a positive result. Since the implementation of such plans has not been yet launched in Greece, it is vital to produce a theoretical frame, through academia, in order to organize the forthcoming development based on a strong cultural and scientific argumentation. These are the data and the main objective of this dissertation. Through the analysis of the nature of the archaeological sites and their context, the discussion of relevant theoretical issues and with the notion of achieving efficient communication between them and the public, I am trying to outline both the restrictions and the opportunities of the topic at hand. This is the first PhD Thesis that discusses this particular subject in Greece. Main objective is to promote scientific debate over the subject of underwater cultural heritage on an academic level and to provide reference in theoretical and methodological aspects in future endeavors.Η εξέλιξη και τα εντυπωσιακά ευρήματα της υποβρύχιας αρχαιολογίας από τη μία και το ολοένα μεγαλύτερο ενδιαφέρον για την ορθότερη και αποτελεσματικότερη διαχείριση της πολιτισμικής κληρονομιάς από την άλλη, διαμορφώνουν ένα ευρύ πλαίσιο, μέσα στο οποίο αναπτύσσονται τα τελευταία χρόνια διάφορες δυναμικές τάσεις για τη διαχείριση της ενάλιας πολιτιστικής κληρονομιάς, τόσο σε τοπικό, όσο και σε παγκόσμιο επίπεδο. Διεθνείς συνθήκες και συνέδρια αναζητούν μία κοινή προοπτική σε θεωρητικό επίπεδο, ενώ σημειώνεται μια αξιόλογη προσπάθεια σε διάφορα σημεία του κόσμου από κρατικούς ή τοπικούς φορείς, ώστε να αξιοποιηθεί στην πράξη το υποβρύχιο πολιτιστικό κεφάλαιο. Στην Ελλάδα για πολλά χρόνια ο τομέας αυτός της πολιτιστικής κληρονομιάς – παραδόξως - δεν είχε δεχθεί τη δέουσα προσοχή. Ωστόσο, τα τελευταία χρόνια αρχίζει σιγά σιγά το θέμα να συζητείται με αξιώσεις, καθώς έχουν δημιουργηθεί οι κατάλληλες συνθήκες για την εξέλιξη του. Το πλήθος των ελληνικών ενάλιων αρχαιοτήτων και η βεβαιότητα για την ύπαρξη μεγάλου αριθμού μελλοντικών ανακαλύψεων, η καθαρότητα των ελληνικών νερών και η ποιότητα του θαλάσσιου περιβάλλοντος και τέλος, η πλούσια ναυτική ιστορία και παράδοση της χώρας, αποτελούν παράγοντες που επιβάλλουν την προσπάθεια προστασίας και αξιοποίησης του ενάλιου πολιτιστικού αποθέματος. Σε συνδυασμό μάλιστα με τις κοινωνικές και οικονομικές συνθήκες η επιλογή αυτή δείχνει να έχει αξιόλογες δυνατότητες. Καθώς λοιπόν, η εκπόνηση σχεδίων σε αυτό τον τομέα έχει ήδη αρχίσει και η εφαρμογή τους αναμένεται στο κοντινό μέλλον, γεννάται η ανάγκη να υπάρξουν αντίστοιχες μελέτες και σε ακαδημαϊκό επίπεδο. Σε αυτό το πλαίσιο εντάσσεται και η εκπόνησης της συγκεκριμένης διδακτορικής διατριβής στο τμήμα Αρχιτεκτόνων της Πολυτεχνικής Σχολής του Α.Π.Θ. Μέσα από την ανάλυση της φύση των ίδιων των αρχαιολογικών θέσεων και ευρημάτων, τη μελέτη θεωρητικών ζητημάτων, αλλά και τους τρόπους επικοινωνίας με το κοινό, προκύπτουν οι παράγοντες, που διαμορφώνουν τόσο τους περιορισμούς, όσο και τις δυνατότητες του θέματος, που απασχολεί την παρούσα μελέτη. Η παρούσα διατριβή αποτελεί την πρώτη συστηματική εργασία στο συγκεκριμένο θέμα στην ελληνική επιστημονική βιβλιογραφία. Στόχος της είναι να συμβάλλει στην ανάπτυξη της επιστημονικής συζήτησης για τη διαχείριση της υδάτινης πολιτιστικής κληρονομιάς στην Ελλάδα σε ακαδημαϊκό επίπεδο, αλλά και να αποτελέσει ένα κείμενο αναφοράς για το θεωρητικό και μεθοδολογικό σχεδιασμό δράσεων προστασίας και ανάδειξης