Εφαρμογή της Ιατρικής Ακριβείας (Precision Medicine) στη διαχείριση και θεραπευτική αντιμετώπιση ασθενών με ημικρανία

Η ημικρανία αποτελεί συχνή διαταραχή που επηρεάζει αρνητικά σημαντικό ποσοστό ασθενών, με αντίστοιχο κοινωνικό και οικονομικό κόστος. Πρόκειται για μία νευροαγγειακή νόσο, της οποίας οι παθοφυσιολογικοί μηχανισμοί διερευνώνται μέχρι σήμερα. Και ενώ η φλοιώδης μετακινούμενη καταστολή (CSD) και η δυσλειτουργία του τριδυμοαγγειακού συστήματος φαίνεται ότι διαδραματίζουν βασικό ρόλο στην εμφάνιση της αύρας και του πόνου που χαρακτηρίζει την ημικρανία, η μελέτη του ανθρώπινου γονιδιώματος κατέδειξε τη συμμετοχή αρκετών γονιδίων και νευροπεπτιδίων στην παθογένειά της. Τα νέα δεδομένα καθιστούν αναγκαία την αναζήτηση στοχευμένων μεθόδων στη διάγνωση και θεραπεία της νόσου, δεδομένου ότι οι τρέχουσες θεραπευτικές προσεγγίσεις σε αρκετές περιπτώσεις εμφανίζουν μικρή αποτελεσματικότητα και σημαντική ανεπιθύμητη δράση. Σήμερα, η ταχεία ανάπτυξη της γενετικής ανοίγει νέους ορίζοντες στην προσέγγιση της ημικρανίας μέσα από το πρίσμα της Ιατρικής Ακριβείας (Precision Medicine, PM). Η Ιατρική Ακριβείας αποτελεί μία νέα προσέγγιση της θεραπείας και της πρόληψης της νόσου, η οποία συνδυάζει την εξατομικευμένη προσέγγιση του ασθενούς με το σχεδιασμό και εφαρμογή της κατάλληλης θεραπείας. Διαφέρει ριζικά από την προσέγγιση του “ one size fits all”, οδηγώντας στην καλύτερη κατανόηση των παθοφυσιολογικών μηχανισμών των ασθενειών και στην ανάπτυξη καινοτόμων διαγνωστικών και θεραπευτικών επιλογών. Συνδυάζει την αποκωδικοποίηση του γονιδιώματος και τη συσχέτιση της επιστήμης της Βιοχημείας με τη συννοσηρότητα του ασθενούς, προκειμένου να επιτευχθεί το βέλτιστο κλινικό αποτέλεσμα. Σκοπός της εργασίας είναι η παρουσίαση των θεραπευτικών οδηγιών για την αντιμετώπιση της ημικρανίας και η διερεύνηση της δυνατότητας εφαρμογής τους, σύμφωνα με τα νέα δεδομένα της Ιατρικής Ακριβείας (Precision Medicine, PM). Η διερεύνηση και ταυτοποίηση νέων γενετικών, επιγενετικών, βιοχημικών και άλλων βιοδεικτών θα προσδώσει τη δυνατότητα καλύτερης προσέγγισης του ασθενούς, πιο στοχευμένης θεραπείας και μείωσης του κόστους διαχείρισης της νόσουMigraine is a common disorder that negatively affects a significant percentage of patients, with corresponding social and economic costs. It is a neurovascular disease whose pathophysiological mechanisms are still being examined. While cortical spreading depression (CSD) and dysfunction of the trigeminovascular system appear to play a key role in the onset of migraine aura and pain, the study of human genome has shown the involvement of several genes and neuropeptides in its pathogenesis. New data make it necessary to search for targeted methods in the diagnosis and treatment of the disease, as current therapeutic approaches in many cases show little effectiveness and significant side effects. Nowadays, the rapid development of genetics opens new horizons in the approach of migraine through the prism of Medical Precision. Precision Medicine (PM) is a new approach to the treatment and prevention of the disease, which combines the individualized approach of the patient with the design and implementation of appropriate treatment. It differs radically from the "one size fits all" approach, leading to a better understanding of the pathophysiological mechanisms of the disease and the development of innovative diagnostic and treatment options. It combines the expression of genome and the correlation of science of Biochemistry with the comorbidity of the patient, in order to achieve the optimal clinical result. The purpose of this essay is to present the current therapeutic approaches for migraine treatment and to investigate their applicability, according to the new data of Medical Precision. The investigation and identification of new genetic, epigenetic, biochemical and other biomarkers will enable the patient to be better approached, more targeted treatment and reduced disease’s management costs

Acoustic emission behavior of steel fibre reinforced concrete under bending

The present paper describes the acoustic emission (AE) behavior of concrete under four-point bending. Steel fibres of varying content were used as reinforcement in concrete slabs and their influence on the fracture process and the acoustic activity was investigated. The total acoustic emission (AE) activity was found to be directly proportional to the fibre content. Analysis revealed that particular AE parameters change monotonically with the progress of damage and can be used for the characterization of the failure process

Acoustic emission behavior of steel fibre reinforced concrete under bending

a b s t r a c t The present paper describes the acoustic emission (AE) behavior of concrete under four-point bending. Steel fibres of varying content were used as reinforcement in concrete slabs and their influence on the fracture process and the acoustic activity was investigated. The total acoustic emission (AE) activity was found to be directly proportional to the fibre content. Analysis revealed that particular AE parameters change monotonically with the progress of damage and can be used for the characterization of the failure process

Injection moulded all-polypropylene composites composed of polypropylene fibre and polypropylene based thermoplastic elastomer

All-polypropylene composites comprising of polypropylene based thermoplastic elastomer (TPE) matrix and homo-polypropylene (hPP) fibre reinforcement were prepared and processed by injection moulding. For the injection moulding of plaque specimens pre-impregnated pellets, prepared by combined filament winding and film stacking were used. The processing-structure-property relationships of the all-PP composites were studied on specimens cut from the plaques produced at different melt temperatures (120, 140, 160°C). The properties determined covered the mouldinginduced shrinkage, flexural stiffness via dynamic mechanical analysis, static tensile and high-speed perforation impact behaviours. It was demonstrated that by using TPE as matrix the processing window of this novel all-PP composite could be significantly increased. The static tests demonstrated that the yield stress and tensile modulus of the all-PP composites were prominently increased. Optical micrographs taken from polished sections of the composites confirmed good interfacial adhesion between the matrix and the fibres. It was established that the shrinkage behaviour of the TPE based all-polypropylene composites is similar to that of conventional polypropylene

Preparation and characterization of compression-molded green composite sheets made of poly(3-hydroxybutyrate) reinforced with long pita fibers

[EN] Novel green composites were successfully prepared from bacterial poly(3-hydroxybutyrate) (PHB) and pita fibers derived from the agave plant (Agave americana). Various weight contents (10, 20, 30, and 40 wt.-%) of pita fibers at different lengths (5, 15, and 20 mm) were successfully incorporated into PHB by compression molding. The newly prepared PHB/pita fibers composite sheets were characterized in terms of their mechanical and thermomechanical properties and then related to their morphology after fracture. Attained results indicated that the mechanical stiffness of PHB significantly improved with both the content and length of pita fibers, although ductile properties were reduced. In particular, the elastic modulus of the 40 wt.-% PHB composite sheets containing 20-mm-long pita fibers was approximately 55% higher than the unfilled PHB sheet. Shore D hardness also improved, achieving the shortest pita fibers the highest improvement. Pita fibers with lengths of 15 and 20 mm also increased the Vicat softening point and heat deflection temperature (HDT) by 38 and 21°C, respectively. Due to their optimal shape, it is concluded that pita fibers with lengths above 15 mm can potentially reinforce and improve the performance of PHB biopolymer. In addition, the compression-molding methodology described in this research work represents a cost-effective pathway to feasibly prepare long-fiber- reinforced thermoplastics (LFRTs) fully based on renewable raw materials. Resultant green composite sheets can be of interest for the development of sustainable parts in the automotive industry and other advanced applications in polymer technology.This research was supported by the Spanish Ministry of Economy and Competitiveness (project MAT2014-59242- C2-1-R). The authors also thank “Conselleria d’Educació, Cultura i Esport—Generalitat Valenciana” (grant number GV/2014/008) for financial support.Torres-Giner, S.; Montanes, N.; Fombuena, V.; Boronat, T.; Sanchez-Nacher, L. (2016). Preparation and characterization of compression-molded green composite sheets made of poly(3-hydroxybutyrate) reinforced with long pita fibers. Advances in Polymer Technology. 1-11. https://doi.org/10.1002/adv.21789S11

Single-Polymer Composites (SPCs) : Status and Future Trends

Preparation, properties and applications of single-polymer composites (SPCs), representing an emerging family within the polymeric composite materials, have been surveyed. SPCs were classified in respect to their composition (one- and two-constituents), and preforms (non-consolidated and consolidated). SPCs composed of amorphous or semicrystalline matrices and semicrystalline reinforcements were considered. Methods to widen the temperature difference between the matrix- and reinforcement-giving materials of the same polymer (one-constituent) or same polymer type (two-constituent approach) have been introduced and discussed. Special attention was paid to the unsolved questions related to the interface/interphase in SPCs. It was emphasized that the development of SPCs is fuelled by the need of engineering parts in different applications which have low density and “ultimate” recyclability (i.e. reprocessing via remelting). Recent development of SPCs is supported by novel preform preparation, consolidation and production possibilities

On the fatigue life prediction of CFRP laminates using the Electrical Resistance Change method

International audienceThe electromechanical response (Electrical Resistance Change method) as a damage index of quasi-isotropic Carbon Fiber Reinforced (CFRPs) laminates under fatigue loading was investigated. The effect of dispersed Multi-Wall Carbon Nanotubes (MWCNT) into the epoxy matrix was additionally evaluated and compared with neat epoxy CFRPs. The longitudinal resistance change of the specimens was monitored throughout the fatigue experiment. Three different stress levels were tested. The frequency and the ratio (R) of the minimum applied load (stress) to the maximum applied load (stress) were kept constant for the different stress levels. The temperature of the specimen was also monitored throughout the process in order to deduce its effect on the electrical resistance of the specimen. The electrical behavior of the quasi-isotropic CFRP deviated from the commonly observed electrical response of unidirectional or cross-ply CFRPs due to the presence of the 45 layers. During initial stages of loading the resistance drops and afterwards it follows a positive slope up to final fracture. This repeatable pattern was observed for both the neat and the CNT-doped specimens, with the latter having smoother electrical recordings. The effect of temperature was calculated to be limited for the specific material and test/measurement configuration. The electromechanical response was correlated to stiffness degradation and acoustic emission findings enabling the identification of the specific regions during the fatigue life referring to specific mechanisms of damage accumulation. More specifically the experimental results revealed that the occurrence of the initial drop of the electrical resistance is linked with the occurrence of the Characteristic Damage State (CDS), associated with a specific percentage of stiffness reduction. This finding was used in order to predict the remaining life independently from the applied stress level with a high degree of confidence, assuming a constant stress level throughout the whole lifetime. The remaining life prediction for the CNT-doped specimens had higher coefficient of confidence (R)