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The enzyme ataxia-telangiectasia mutated (ATM) kinase is a pluripotent signaling mediator which activates cellular responses to genotoxic and metabolic stress. It has been shown that ATM enables the growth of mammalian adenocarcinoma stem cells, and therefore the potential benefits in cancer chemotherapy of a number of ATM inhibitors, such as KU-55933 (KU), are currently being investigated. We assayed the effects of utilizing a triphenylphosphonium-functionalized nanocarrier delivery system for KU on breast cancer cells grown either as a monolayer or in three-dimensional mammospheres. We observed that the encapsulated KU was effective against chemotherapy-resistant mammospheres of breast cancer cells, while having comparably lower cytotoxicity against adherent cells grown as monolayers. We also noted that the encapsulated KU sensitized the mammospheres to the anthracycline drug doxorubicin significantly, while having only a weak effect on adherent breast cancer cells. Our results suggest that triphenylphosphonium-functionalized drug delivery systems that contain encapsulated KU, or compounds with a similar impact, are a useful addition to chemotherapeutic treatment schemes that target proliferating cancers.

Το παρόν επιστημονικό σύγγραμμα με τίτλο Ειδικά θέματα της Ιστορίας της Τέχνης του 20ού αιώνα απευθύνεται στους φοιτητές που έχουν στο πρόγραμμα σπουδών τους το μάθημα Ιστορία της Τέχνης του 20ού αιώνα [Σχολή Εφαρμοσμένων Τεχνών και Πολιτισμού, Πανεπιστήμιο Δυτικής Αττικής, Α.Σ.Κ.Τ. (Αθήνα), Σχολή Καλών Τεχνών (Α.Π.Θ.), Τμήματα Ιστορίας και Αρχαιολογίας, Τμήματα Θεατρικών Σπουδών]. Στο σύγγραμμα περιλαμβάνονται 12 κεφάλαια, τα οποία παραπέμπουν σε καλλιτεχνικά κινήματα του 20ού αιώνα. Κάθε καλλιτεχνικό κίνημα περιγράφεται μέσω ενός χαρακτηριστικού θέματος που απασχολεί τους καλλιτέχνες και φωτογραφίζει την εποχή άνθισης του κινήματος. Τα κεφάλαια του συγγράμματος είναι τα ακόλουθα: 1. Το πρωτόγονο στη ζωγραφική των Γερμανών εξπρεσιονιστών 2. Μοντέρνα γλυπτική και πρωτογονισμός (Primitivism) 3. Επιστροφή στη λογική: Μια νέα ερμηνεία του κόσμου. Το έργο των κυβιστών ζωγράφων 4. Η μηχανή, σύμβολο των Ιταλών Φουτουριστών 5. Οι αρχαίοι μύθοι στη Μεταφυσική ζωγραφική των αδελφών de Chirico 6. Όνειρα και εφιάλτες στο έργο των Σουρεαλιστών 7. Το παραλογικό στοιχείο στην τέχνη. Παραφράσεις ενός θέματος: Η περίπτωση του Ubu Roi 8. Η «εμψύχωση» του αντικειμένου ως απήχηση της Pop Art 9. Φωτογραφικός ρεαλισμός: Ένα παρεξηγημένο κίνημα 10. Appropriation Art: Δημιουργία ή ακινησία; 11. Street Art: Η τέχνη του εφήμερου 12. Μορφές του Θεάτρου Σκιών στην ελληνική ζωγραφική του 20ού αιώνα Κάθε κεφάλαιο ολοκληρώνεται με χωρία από θεωρητικά κείμενα (διακηρύξεις καλλιτεχνικών ομάδων, κείμενα καλλιτεχνών, κ.ά.), που συμβάλουν στην εμβάθυνση σημαντικών θεμάτων της Ιστορίας της τέχνης του 20ού αιώνα. Τα κείμενα προσφέρονται για περεταίρω μελέτη και καλούν τους φοιτητές να στοχαστούν γύρω από καίρια ζητήματα της Ιστορίας της τέχνης. Κάθε κεφάλαιο αρχίζει με μια σύντομη σύνοψη της ύλης και ολοκληρώνεται με ασκήσεις ανακεφαλαίωσης. Το παρόν σύγγραμμα παρέχει τη δυνατότητα στους φοιτητές να το χρησιμοποιήσουν ως βοήθημα είτε να επιλέξουν μεμονωμένα θέματα και να εμβαθύνουν σε αυτά.

Our point was to examine if there exists correlation between reaction time and impulsivity in motor behaviours

The abilities of sub-cellular targeting and stimuli-responsiveness are critical challenges in pharmaceutical nanotechnology. In the present study, glyceryl monooleate (GMO)-based non-lamellar lyotropic liquid crystalline nanoparticles were stabilized by the poly(2-(dimethylamino)ethyl methacrylate)-b-poly(lauryl methacrylate) block copolymer carrying tri-phenyl-phosphine cations (TPP-QPDMAEMA-b-PLMA), either used alone or in combination with other polymers as co-stabilizers. The systems were designed to perform simultaneously sub-cellular targeting, stimuli-responsiveness and to exhibit stealthiness. The physicochemical characteristics and fractal dimensions of the resultant nanosystems were obtained from light scattering techniques, while their micropolarity and microfluidity from fluorescence spectroscopy. Their morphology was assessed by cryo-TEM, while their thermal behavior by microcalorimetry and high-resolution ultrasound spectroscopy. The analyzed properties, including the responsiveness to pH and temperature, were found to be dependent on the combination of the polymeric stabilizers. The subcellular localization was monitored by confocal microscopy, revealing targeting to lysosomes. Subsequently, resveratrol was loaded into the nanosystems, the entrapment efficiency was investigated and in vitro release studies were carried out at different conditions, in which a stimuli-triggered drug release profile was achieved. In conclusion, the proposed multi-functional nanosystems can be considered as potentially stealth, stimuli-responsive drug delivery nanocarriers, with targeting ability to lysosomes and presenting a stimuli-triggered drug release profile.

Agricultural soil (Ap-horizon, 0–20 cm) samples were collected from 33 European countries as part of the GEMAS (GEochemical Mapping of Agricultural and grazing land Soil) soil-mapping project. The Mg data derived from total concentrations (XRF) and two acid digestion methods, aqua regia (AR) and Mobile Metal Ion (MMI®), were used to provide an overview of its spatial distribution in soil at the continental-scale. Magnesium is one of the most abundant elements in the Earth's crust and essential nutrient for plants and animals and its presence in soil is, therefore, important for soil quality evaluation. In this study, the geochemical behaviour of Mg in European agricultural soil was investigated in relation to a variety of soil parent materials, climatic zones, and landscapes. The chemical composition of soil reflects mostly the primary mineralogy of the source bedrock, and the superimposed effects of pre- and post-depositional chemical weathering, controlled by element mobility and formation of secondary phases such as clays. Low Mg concentrations in agricultural soil occur in regions with quartz-rich glacial sediments (Poland, Baltic States, N. Germany), and in soil developed on quartz-rich sandstone parent materials (e.g., central Sweden). High Mg concentrations occur in soil developed over mafic lithologies such as ophiolite belts and in carbonate-rich regions, including karst areas. The maximum extent of the last glaciation is well defined by a Mg concentration break, which is marked by low Mg concentrations in Fennoscandia and north-central Europe, and high Mg concentrations in Mediterranean region. Lithology of parent materials seems to play a key role in the Mg nutritional status of agricultural soil at the European scale. Influence from agricultural practice and use of fertilisers appears to be subordinate. Comparison of the continental-scale spatial distribution of Mg in agricultural soil by using the results from three analytical methods (XRF, AR and MMI®) provides complementary information about Mg mobility and its residence time in soil. Thus, allowing evaluation of soil weathering grade and impact of land use exploitation.

This study demonstrates the use of digital image processing for the spatial pattern recognition and characterisation of Ni concentrations in topsoil in Europe. Moving average smoothing was applied to the TIN-interpolated grid model to suppress small irregularities. Digital image processing was applied then to the grid. Several NE-SW, E-W and NW-SE oriented features were revealed at the continental scale. The dominant NE-SW linear features follow the Variscan and Alpine orogenies. The highest variability zones are in the Alps and the Balkans where mafic and ultramafic rocks outcrop. A single major E-W oriented north-facing feature runs along the last continental glaciation zone. This zone also coincides with a series of local maxima in Ni concentration along the glaciofluvial deposits. The NW-SE elongated features are located in the Pyrenees, northern Italy, Hellas and Fennoscandia. This study demonstrates the advantages of digital image processing analysis in identifying and characterising spatial geochemical patterns unseen before on conventional colour-surface maps.

The purpose of the present paper is to investigate the factors contributing to the sustainability of Social Cooperative enterprises in Greece as these were perceived by the social entrepreneurs the...

Today, non-destructive testing includes diagnostic methods that provide significant information for art historians, conservators and researchers. The quick in situ application, the absence of expensive consumables, the inspection of entire surfaces and the ability for mapping make these methods attractive to users. Additionally, they provide the advantage of examining large areas of work of art, supporting a multidisciplinary approach, documentation, analysis and protection of visual arts’ works. The case studies presented here involve the application of methodology on paintings on wood, canvas and paper substrate, while the constraints and particular requirements that different structures and special conditions dictate are discussed. Through these case studies the authors intend to highlight that the application of modern non-destructive methods offer many possibilities to the end user, making feasible the revelation of the painting technique, the characterization of the materials and supporting the decision making for conservation.

To address the major medical need for effective chemotherapeutics/diagnostics for brain cancer, in this work three cyclopentadienyl M(CO)

Ένα από τα κύρια χαρακτηριστικά της νόσου Alzheimer (ΝΑ) αποτελεί η συσσώρευση του ολιγομερούς Αβ πεπτιδίου (Αβ), το οποίο πιθανώς αποτελεί την κύρια αιτία για τη νευρική δυσλειτουργία που παρατηρείται στη νόσο. Ένα από τα κυτταρικά μονοπάτια που πλήττεται από τη δράση των Αβ ολιγομερών αφορά το μονοπάτι κυτταρικής επιβίωσης της ινσουλίνης. Αντιθέτως, η ορθή κυτταρική σηματοδότηση της ινσουλίνης αποτελεί έναν από τους αμυντικούς μηχανισμούς έναντι της συναπτικής απώλειας. Έχει αποδειχθεί από προηγούμενες μελέτες ότι η μεταλλοπρωτεϊνάση-9 (MMP-9), ένα ένζυμο της εξωκυττάριας ουσίας, στενά συνδεδεμένο με τη συναπτική πλαστικότητα, πιθανόν να έχει νευροπροστατευτικές ιδιότητες στη ΝΑ, καθώς έχει την ιδιότητα να μειώνει τη δημιουργία των Αβ ολιγομερών. Στην παρούσα διατριβή μελετήθηκε ο ρόλος της MMP-9 στο ινσουλινο-εξαρτώμενο μονοπάτι επιβίωσης σε δύο διαφορετικά συστήματα: σε πρωτογενείς νευρώνες ιππόκαμπου και σε ιστούς ιππόκαμπου νεαρών μυών 3 μηνών. Μελετήθηκαν 4 διαφορετικοί γονότυποι: μυς μοντέλα της NA (5XFAD), μυς που υπερεκφράζουν την MMP-9 (TgMMP-9), διπλά διαγονιδιακοί μυς (5XFAD/TgMMP-9) και μυς άγριου τύπου (WT). Από τα αποτελέσματα προκύπτει ότι το ινσουλινο-εξαρτώμενο μονοπάτι επιβίωσης διαταράσσεται στα δείγματα από τους 5XFAD μυς και στα 2 πειραματικά συστήματα σε σύγκριση με τους μυς που υπερεκφράζουν την MMP-9 ή τους μυς άγριου τύπου. Συγκεκριμένα, ανιχνεύθηκε αυξημένη φωσφορυλίωση του IRS1 στη σερίνη 636, η οποία προκαλεί την απενεργοποίηση του και οδηγεί στην αναστολή της σηματοδότησης της ινσουλίνης. Αντιθέτως, το γεγονός αυτό απετράπη στους 5XFAD/TgMMP-9 μυς, λόγω της αυξημένης φωσφορυλίωσης του IRS1 στη τυροσίνη 465, η οποία συνοδεύτηκε από αυξημένα επίπεδα του παράγοντα BDNF και αυξημένη ενεργοποίηση του υποδοχέα TrkB. Παράλληλα, ανιχνεύθηκε αυξημένη φωσφορυλίωση των Akt και GSK-3β κινασών, καθώς και μειωμένη φωσφορυλίωση της JNK κινάσης. Τέλος, στους ίδιους μυς παρατηρήθηκε μικρότερο ποσοστό κυτταρικής απόπτωσης στις πρωτογενείς κυτταροκαλλιέργειες, καθώς και μειωμένα επίπεδα Αβ ολιγομερών στους ενήλικες μυς σε σχέση με τους 5XFAD μυς. Συνολικά, τα ευρήματα της παρούσας μελέτης συνηγορούν στο ότι η υπερέκφραση της MMP-9 επαναφέρει την κυτταρική σηματοδότηση της ινσουλίνης τόσο in vitro, όσο και σε πρώιμα στάδια της νόσου στο 5XFAD μοντέλο της ΝΑ. Συνεπώς, η ενίσχυση της ινσουλινο-εξαρτώμενης οδού επιβίωσης, μέσω της ελεγχόμενης έκφρασης της MMP-9, θα μπορούσε πιθανώς να αποτελέσει μια καινοτόμο και ελπιδοφόρο θεραπευτική στρατηγική.

The paper contributes new information about the Horologion of Andronikos Kyrristos of the Roman Agora of Athens, Greece and its continuous presence in Athens from antiquity until now. The monument is of cultural, historical and astronomical importance. It has undergone conservation work and non-destructive documentation which contribute to its sustainability. The spectral imaging technique, which allows the acquisition of high-resolution images, was applied on the stone surfaces of the monument. The acquisition of images in the visible and infrared regions, combined with the digital tracing reproduction of the graffiti and image processing, is used for the first time in this particularly interesting case study of the aforementioned monument, of which a complete description is provided. New evidence with a clearer recording of the vessels already mentioned in the literature, as well as the detection of new historical data and graffiti, is discussed in comparison with the results of previous studies.

An efficient doxorubicin (DOX) drug delivery system with specificity against tumor cells was developed, based on multi-walled carbon nanotubes (MWCNTs) functionalized with guanidinylated dendritic molecular transporters. Acid-treated MWCNTs (oxCNTs) interacted both electrostatically and through hydrogen bonding and van der Waals attraction forces with guanidinylated derivatives of 5000 and 25,000 Da molecular weight hyperbranched polyethyleneimine (GPEI5K and GPEI25K). Chemical characterization of these GPEI-functionalized oxCNTs revealed successful decoration with GPEIs all over the oxCNTs sidewalls, which, due to the presence of guanidinium groups, gave them aqueous compatibility and, thus, exceptional colloidal stability. These GPEI-functionalized CNTs were subsequently loaded with DOX for selective anticancer activity, yielding systems of high DOX loading, up to 99.5% encapsulation efficiency, while the DOX-loaded systems exhibited pH-triggered release and higher therapeutic efficacy compared to that of free DOX. Most importantly, the oxCNTs@GPEI5K-DOX system caused high and selective toxicity against cancer cells in a non-apoptotic, fast and catastrophic manner that cancer cells cannot recover from. Therefore, the oxCNTs@GPEI5K nanocarrier was found to be a potent and efficient nanoscale DOX delivery system, exhibiting high selectivity against cancerous cells, thus constituting a promising candidate for cancer therapy.

The demand of energy utilization is increasing expressively as fast as the development of countries. Besides being available everywhere and virtual inexhaustible, renewable energy is undoubtedly necessary to avoid depleting the planet’s natural resources and global warming. Even considering the primordially environmental importance, the result of no emissions by renewable energy grant attractive also for political and economics statement. It should be noted the sun is the most abundant primary energy source in the planet and essential for eco-friendly process like photosynthesis, wind action, water cycle as well direct uses as electric and thermal generations. Consequently, nowadays several methodologies have been applied in order to transfer energy between the cycle and its surroundings optimizing for instance the coefficient of performance and heat exchangers. An absorption system is widely applied in these cases due to supply a unique solution for a range of technological problems from solar cooling to steam-driven refrigeration. Alternatively, this article main objective is modulating an absorption refrigeration system (ARS) which uses water-lithium bromide as a working fluid. Therefore, using the software Engineering Equation Solver (EES) is possible to obtain a thermodynamic single effect code that allows elaborating parametric analyses. In other words, performed and verified the influence of some input parameters over other output parameters. First, it was necessary to consider the cycle operating as reversible and steady state. Furthermore, it is assumed that no chemical reactions occur between water and lithium bromide. Thus, in the meantime apply the heat exchangers and a Solar Collector to receive the thermal energy and provide to the refrigeration cycle. Similarly, water from external sources was used to change heat with the fluid water-lithium bromide. Satisfactory results were founded and it enable to calculate and evaluate all system heat transfers rates and coefficient of performance. Almost all of input parameters introduced brought adequate values over output parameters, but the most convenient were: mass balance of water-lithium bromide solution and temperature of cold water from outside source. Clearly, results always can be found but in conclusion this article can be used to verify parameters sensitivity, optimized absorption refrigeration solutions and supply knowledge for future applications.