Novel insights into an old controversy: Is coronary artery ectasia a variant of coronary atherosclerosis?

Coronary artery ectasia (CAE) is defined as a localized or diffuse non-obstructive lesion of the epicardial coronary arteries with a luminal dilation exceeding 1.5-fold the diameter of the normal adjacent arterial segment. The incidence of CAE has been reported to range between 2% and 4%, which might be an overestimation of the true frequency. The coincidence of CAE with other systemic vascular dilatations has suggested that the mechanism underlying CAE is not only localized to coronary arteries, but also to other vascular compartments such as aorta or peripheral veins. Although the pathophysiology of CAE remains largely unknown, it was supposed to represent a variant of coronary atherosclerosis. This review focuses on this controversy of whether CAE and coronary artery disease (CAD) are two manifestations of the same underlying process. There are clear differences between CAD and CAE with respect to cardiovascular risk factors such as diabetes mellitus, and pathogenic steps in disease progress such as inflammation or extracellular matrix remodeling. As this review will underscore, the current knowledge of the field is insufficient to finally clarify the causative interrelation between CAE and CAD. The clinical course and treatment of CAE mainly depends on its coexistence with CAD. When coexisting with CAD, the prognosis and treatment of CAE are the same as for CAD alone. In isolated CAE, prognosis is better and anti-platelet drugs are the mainstay of treatment. Surgical treatment can be considered in selected patients. For clarifying the mechanism underlying CAE, additional clinical, histopathological and pathophysiological investigations are required. In fact, every patient with CAE should be evaluated systematically for pathological changes in other vascular territories, both in the arterial system as well as in the venous system, which might occur in the disease process

Polypyridyl Ru(II) complexes conjugated with amino acids: Synthesis, characterization and DNA interactions

Diastereomeric oligopyridine-Ruthenium(II)-amino acid conjugated complexes of the general formulas Λ- and Δ-[Ru(bpy)₂(4,4'-(CΟ₂Y)2- bpy)]²⁺, where Y = L-AlaCONH₂, L-LysCONH₂, L-HisCONH₂, L-TyrCONH₂) were synthesized and characterized. Their binding properties with ct-DNA and the oligonucleotide duplex d(5'-CGCGCG-3’)₂, by means of circular dichroism (CD), NMR spectroscopy and DNA thermal denaturation (Tm) curves were studied. CD and Tm data indicate that all diastereomeric complexes bind to the DNA major groove, Δ-diastereomers in a similar manner, while Λ-ones in dependence of the nature of the amino acid. NMR studies of the d(5'-CGCGCG-3’)₂, and the complexes Δ-1, Δ-2, Λ-1 and Λ-2 indicate that Δ-1 and Δ-2 were bound having the ancillary bpy ligands towards the DNA groove, while the corresponding Λ-l and Λ-2 were orientated in a similar way, facing the ligand 4,4'-(CO₂Y)₂bpy towards the DNA major groove. Photo induced DNA cleavage was observed in all cases studied, which take place through singlet oxygen production. The complex [Ru(terpy)₂(4,4'-(CO₂LysCONH₂)₂- bpy)]²⁺ were spectroscopically characterized and its DNA-binding properties were studied with the oligonucleotide duplex d(5'-CGCGCG-3’)₂ and the d(5’-CGCGCG-3’)₂, CT-DNA and plasmid DNA. The results show that the complex interacts by coordination to the DNA bases preferring the bases guanine with the conjugated amino acid able to provide an additional interaction with the DNA helix. In addition, electrostatic interactions between the studied complex and the DNA polyanion were observed.Στην παρούσα διατριβή παρουσιάζονται τα αποτελέσματα της σύνθεσης πολυπυριδινικών συμπλοκών του Ru(II), του τύπου Λ- and Δ-[Ru(bpy)₂(4,4'-(CΟ₂Y)2- bpy)]²⁺, όπου Y = L-AlaCONH₂, L-LysCONH₂, L-HisCONH₂, L-TyrCONH₂, τα οποία χαρακτηρίστηκαν πλήρως με διάφορες φασματοσκοπικές και αναλυτικές τεχνικές. Μελετήθηκαν οι αλληλεπιδράσεις των συμπλόκων αυτών με ct-DNA και με το ολιγονουκλεοτίδιο d(5'-CGCGCG-3’)₂, με φασματοσκοπία κυκλικού διχρωισμού (CD), με φασματοσκοπία πυρηνικού μαγνητικού συντονισμού (NMR) και με την μέθοδο μέτρησης της θερμοκρασίας τήξης τον DNA (Tm). Τα αποτελέσματα από το CD και το Tm έδειξαν ότι τα σύμπλοκα δεσμεύονται στην κύρια αύλακα. Τα Δ διαστερεομερή αλληλεπιδρούν με την διπλή έλικα από την πλευρά των διπυριδιλίων με ανάλογο τρόπο, ενώ τα Λ βρέθηκε να αλληλεπιδρούν μέσω ηλεκτροστατικών αλληλεπιδράσεων λόγω του κατάλληλου προσανατολισμού της πλευρικής ομάδας των αμινοξέων του υποκαταστάτη. Επίσης βρέθηκε ότι, η νουκλεολυτική δραστικότητα των συμπλοκών εξαρτάται από την φύση του συζευγμένου αμινοξέος και η διάσπαση του DNA πραγματοποιείται μέσω ¹O₂. Συντέθηκε και χαρακτηρίστηκε το σύμπλοκο [Ru(terpy)₂(4,4'-(CO₂LysCONH₂)₂- bpy)]²⁺ και μελετήθηκαν οι αλληλεπιδράσεις του με τα ολιγονοκλεοτίδια d(5'-CGCGCG-3’)₂ και d(5’-CGCGCG-3’)₂, με CT-DNA και πλασμιδιακό DNA. Τα αποτελέσματα έδειξαν ότι το σύμπλοκο δεσμεύεται εκλεκτικά στις βάσεις της γουανίνης έχοντας μια επιπλέον αλληλεπίδραση των δύο συζευγμένων λυσινών κατά την δέσμευση του συμπλόκου στο DNA

Identification of Contributory Factors That Affect the Willingness to Use Shared Autonomous Vehicles

Shared autonomous vehicles (SAVs) aspire to change not only vehicles but also the way people and goods move in urban areas. However, the promotion of such services, that is, whether travelers are willing to share their trips with other service users, is still a challenge. This study aims to examine the contributory factors that influence the willingness of individuals to use shared autonomous vehicles by simultaneously identifying the differences in terms of preferences with conventional competitive transport modes, namely, private cars and public transport. A stated preference experiment combined with perception ratings was designed and conducted in Athens, Greece. Based on the collected responses, a multinomial logit model was estimated. The results show that the flexibility of SAVs and, particularly, the possibility of performing door-to-door trips has a serious added value that travelers are willing to pay. Compared with public transport, additional waiting time does not increase the disutility. Furthermore, people who belong to high-education and -income groups expressed a higher willingness to use SAVs and socialize while traveling. The familiarity of each potential user with technology is a necessary precondition. Lastly, it is confirmed that environmentally conscious people are more positive about using these new services