Εκφοβισμός, Προσωπικότητα και Δεσμός Προσκόλλησης σε Μαθητές Προεφηβικής Ηλικίας

Η εκφοβιστική συμπεριφορά έχει βρεθεί πως συνδέεται με συγκεκριμένα χαρακτηριστικά της προσωπικότητας και το δεσμό προσκόλλησης. Ωστόσο, η σχέση του εκφοβισμού με τους Μεγάλους Πέντε Παράγοντες της προσωπικότητας δεν έχει περιγραφεί επαρκώς. Σκοπός της παρούσας ερευνητικής μελέτης είναι να εξετάσει τη σχέση ανάμεσα στον εκφοβισμό, την προσωπικότητα (μοντέλο Πέντε Παραγόντων) και το δεσμό σε δείγμα 282 μαθητών (43,3% κορίτσια) των τελευταίων 2 τάξεων του δημοτικού σχολείου μέσω ενός ερωτηματολογίου αυτοαναφοράς. Από τις αναλύσεις διαφάνηκε ότι τα αγόρια εκφοβίζουν πιο συχνά επιλέγοντας περισσότερη άμεση επιθετικότητα σχέσεων, φυσική και λεκτική επιθετικότητα, λιγότερη έμμεση επιθετικότητα σχέσεων και συμπεριφορική επιθετικότητα. Επιπλέον, παρατηρήθηκε ότι οι θύτες σημείωσαν χαμηλότερη βαθμολογία στην Ευσυνειδησία και την Καλή Προαίρεση/Συνεργατικότητα και υψηλότερη στη Συναισθηματική Αστάθεια σε σχέση με τους αμέτοχους. Το μεγαλύτερο ποσοστό τόσο των θυτών όσο και των αμέτοχων δήλωσαν ασφαλή δεσμό προσκόλλησης. Οι συσχετίσεις των μεταβλητών έδειξαν ότι ο εκφοβισμός παρουσίασε θετική συσχέτιση με τη συναισθηματική αστάθεια και αρνητική με την ευσυνειδησία, την καλή προαίρεση/συνεργατικότητα και την πνευματική διαθεσιμότητα, ενώ βρέθηκε πως η χρήση διαφορετικών μορφών εκφοβισμού είναι ανεξάρτητη από τα χαρακτηριστικά της προσωπικότητας. Τα ευρήματα υπογραμμίζουν το ρόλο της προσωπικότητας και του δεσμού προσκόλλησης στην εκδήλωση του φαινομένου και συζητούνται στη βάση της προοπτικής αξιοποίησής τους στην εφαρμογή παρεμβατικών προγραμμάτων που στοχεύουν στην ενίσχυση των θετικών χαρακτηριστικών της προσωπικότητας.Bullying has been recognized as a serious problem in many countries, including Greece, with an increasing number of empirical studies investigating the phenomenon in Greek schools. Bullying has been linked to specific personality traits and attachment style. However, to date, relatively little is known about the association between bullying and the Big Five personality factors. Hence, the purpose of the current study is to examine the relationship among bullying, personality (Five Factor Model) and attachment style in a sample of Greek preadolescents. Furthermore, the present research aims to study the various forms of bullying (physical, direct and indirect relational, verbal, behavioral) in order to investigate whether participation in different forms of bullying is related to the same personality characteristics. Overall, 282 students (43,3% girls) attending the last two grades of Greek public elementary school took part in the study. Participants completed a self-report questionnaire measuring bullying, Big Five personality factors and attachment style. Results indicated that participants reported primarily more indirect relational, physical and verbal aggression. Specifically, approximately one quarter of the sample was classified as bullies, while the rest were uninvolved. Data analysis showed that boys participated more frequently in bullying, reporting more direct relational, physical and verbal aggression, and less indirect relational and behavioral aggression compared to girls. Compared to the uninvolved, bullies scored lower on Conscientiousness, Agreeableness, and higher on Emotional Instability. Of special interest was the finding that a high percentage of both bullies and uninvolved participants reported secure attachment style. Further analyses showed that, in terms of gender, most of the bullies reporting secure attachment were boys. However, no statistically significant gender differences in personality traits were evident for this group. Additionally, results indicated that many uninvolved students reported insecure attachment. Particularly, uninvolved girls with insecure attachment reported more Emotional Instability and Agreeableness compared to boys. Correlation analyses for the total sample showed that all forms of bullying were positively associated with Emotional Instability, and negatively with Conscientiousness, Agreeableness and Openness to Experience. Therefore, involvement in different bullying forms was independent of participants’ personality traits. Findings are discussed in terms of prevention and intervention strategies regarding bullying, with practical suggestions including the reinforcement of positive personality traits in bullies, curricular changes, as well as individualized intervention programs for those involved

Human Aldehyde Dehydrogenase 3A1 (ALDH3A1) Exhibits Chaperone-Like Function

Aldehyde dehydrogenase 3A1 (ALDH3A1) is a metabolic enzyme that catalyzes the oxidation of various aldehydes. Certain types of epithelial tissues in mammals, especially those continually exposed to environmental stress (e.g., corneal epithelium), express ALDH3A1 at high levels and its abundance in such tissues is perceived to help to maintain cellular homeostasis under conditions of oxidative stress. Metabolic as well as non-metabolic roles for ALDH3A1 have been associated with its mediated resistance to cellular oxidative stress. In this study, we provide evidence that ALDH3A1 exhibits molecular chaperone-like activity further supporting its multifunctional role. Specifically, we expressed and purified the human ALDH3A1 in E. coli and used the recombinant protein to investigate its in vitro ability to protect SmaI and citrate synthase (from precipitation and/or deactivation) under thermal stress conditions. Our results indicate that recombinant ALDH3A1 exhibits significant chaperone function in vitro. Furthermore, over-expression of the fused histidine-tagged ALDH3A1 confers host E. coli cells with enhanced resistance to thermal shock, while ALDH3A1 over-expression in the human corneal cell line HCE-2 was sufficient for protecting them from the cytotoxic effects of both hydrogen peroxide and tert-butyl hydroperoxide. These results further support the chaperone-like function of human ALDH3A1. Taken together, ALDH3A1, in addition to its primary metabolic role in fundamental cellular detoxification processes, appears to play an essential role in protecting cellular proteins against aggregation under stress conditions

Εκφοβισμός, Προσωπικότητα και Δεσμός Προσκόλλησης σε Μαθητές Προεφηβικής Ηλικίας

Η εκφοβιστική συμπεριφορά έχει βρεθεί πως συνδέεται με συγκεκριμένα χαρακτηριστικά της προσωπικότητας και το δεσμό προσκόλλησης. Ωστόσο, η σχέση του εκφοβισμού με τους Μεγάλους Πέντε Παράγοντες της προσωπικότητας δεν έχει περιγραφεί επαρκώς. Σκοπός της παρούσας ερευνητικής μελέτης είναι να εξετάσει τη σχέση ανάμεσα στον εκφοβισμό, την προσωπικότητα (μοντέλο Πέντε Παραγόντων) και το δεσμό σε δείγμα 282 μαθητών (43,3% κορίτσια) των τελευταίων 2 τάξεων του δημοτικού σχολείου μέσω ενός ερωτηματολογίου αυτοαναφοράς. Από τις αναλύσεις διαφάνηκε ότι τα αγόρια εκφοβίζουν πιο συχνά επιλέγοντας περισσότερη άμεση επιθετικότητα σχέσεων, φυσική και λεκτική επιθετικότητα, λιγότερη έμμεση επιθετικότητα σχέσεων και συμπεριφορική επιθετικότητα. Επιπλέον, παρατηρήθηκε ότι οι θύτες σημείωσαν χαμηλότερη βαθμολογία στην Ευσυνειδησία και την Καλή Προαίρεση/Συνεργατικότητα και υψηλότερη στη Συναισθηματική Αστάθεια σε σχέση με τους αμέτοχους. Το μεγαλύτερο ποσοστό τόσο των θυτών όσο και των αμέτοχων δήλωσαν ασφαλή δεσμό προσκόλλησης. Οι συσχετίσεις των μεταβλητών έδειξαν ότι ο εκφοβισμός παρουσίασε θετική συσχέτιση με τη συναισθηματική αστάθεια και αρνητική με την ευσυνειδησία, την καλή προαίρεση/συνεργατικότητα και την πνευματική διαθεσιμότητα, ενώ βρέθηκε πως η χρήση διαφορετικών μορφών εκφοβισμού είναι ανεξάρτητη από τα χαρακτηριστικά της προσωπικότητας. Τα ευρήματα υπογραμμίζουν το ρόλο της προσωπικότητας και του δεσμού προσκόλλησης στην εκδήλωση του φαινομένου και συζητούνται στη βάση της προοπτικής αξιοποίησής τους στην εφαρμογή παρεμβατικών προγραμμάτων που στοχεύουν στην ενίσχυση των θετικών χαρακτηριστικών της προσωπικότητας.Bullying has been recognized as a serious problem in many countries, including Greece, with an increasing number of empirical studies investigating the phenomenon in Greek schools. Bullying has been linked to specific personality traits and attachment style. However, to date, relatively little is known about the association between bullying and the Big Five personality factors. Hence, the purpose of the current study is to examine the relationship among bullying, personality (Five Factor Model) and attachment style in a sample of Greek preadolescents. Furthermore, the present research aims to study the various forms of bullying (physical, direct and indirect relational, verbal, behavioral) in order to investigate whether participation in different forms of bullying is related to the same personality characteristics. Overall, 282 students (43,3% girls) attending the last two grades of Greek public elementary school took part in the study. Participants completed a self-report questionnaire measuring bullying, Big Five personality factors and attachment style. Results indicated that participants reported primarily more indirect relational, physical and verbal aggression. Specifically, approximately one quarter of the sample was classified as bullies, while the rest were uninvolved. Data analysis showed that boys participated more frequently in bullying, reporting more direct relational, physical and verbal aggression, and less indirect relational and behavioral aggression compared to girls. Compared to the uninvolved, bullies scored lower on Conscientiousness, Agreeableness, and higher on Emotional Instability. Of special interest was the finding that a high percentage of both bullies and uninvolved participants reported secure attachment style. Further analyses showed that, in terms of gender, most of the bullies reporting secure attachment were boys. However, no statistically significant gender differences in personality traits were evident for this group. Additionally, results indicated that many uninvolved students reported insecure attachment. Particularly, uninvolved girls with insecure attachment reported more Emotional Instability and Agreeableness compared to boys. Correlation analyses for the total sample showed that all forms of bullying were positively associated with Emotional Instability, and negatively with Conscientiousness, Agreeableness and Openness to Experience. Therefore, involvement in different bullying forms was independent of participants’ personality traits. Findings are discussed in terms of prevention and intervention strategies regarding bullying, with practical suggestions including the reinforcement of positive personality traits in bullies, curricular changes, as well as individualized intervention programs for those involved

Improved microbubble (MB) Localisation Using Particle Detecting algorithm:Evaluation of Algorithm Performance for Different Beamforming Methods

International audienceThe performance of image analysis techniques (particle detection) on contrast enhanced ultrasound (CEUS) images could be enhanced by using it in combination with the right beamformer (BF). The current study investigates the best performing combination of a particle detecting algorithm (Kanoulas et al. 2019) with four beamformers (BFs), classical and adaptive. In a series of in silico experiments, adjacent MBs are placed in distances comparable to the lateral resolution limit, the CEUS images of the MBs were simulated in FieldII, and finally beamformed with the four methods. The images were processed with the MB detection algorithm and the results were evaluated by the true detections (TD), missed MBs, spurious detections, and localisation uncertainty (LU). For the smallest distances all methods deteriorate but the MV methods provided 4-12% more TD. For the intermediate distances the TD were comparable for all BFs but the adaptive methods provided lower LU. When a set of evaluation metrics is used, the adaptive methods provide marginally but systematically improved results which suggests that, under the appropriate imaging conditions, they could be used to enhance vessel mapping

Aldehyde dehydrogenase 3A1 promotes multi-modality resistance and alters gene expression profile in human breast adenocarcinoma MCF-7 cells

Aldehyde dehydrogenases participate in a variety of cellular homeostatic mechanisms like metabolism, proliferation, differentiation, apoptosis, whereas recently, they have been implicated in normal and cancer cell stemness. We explored roles for ALDH3A1 in conferring resistance to chemotherapeutics/radiation/oxidative stress and whether ectopic overexpression of ALDH3A1 could lead to alterations of gene expression profile associated with cancer stem cell-like phenotype. MCF-7 cells were stably transfected either with an empty vector (mock) or human aldehyde dehydrogenase 3A1 cDNA. The expression of aldehyde dehydrogenase 3A1 in MCF-7 cells was associated with altered cell proliferation rate and enhanced cell resistance against various chemotherapeutic drugs (4-hydroxyperoxycyclophosphamide, doxorubicin, etoposide, and 5-fluorouracil). Aldehyde dehydrogenase 3A1 expression also led to increased tolerance of MCF-7 cells to gamma radiation and hydrogen peroxide-induced stress. Furthermore, aldehyde dehydrogenase 3A1-expressing MCF-7 cells exhibited gene up-regulation of cyclins A, B1, B2, and down-regulation of cyclin D1 as well as transcription factors p21, CXR4, Notch1, SOX2, SOX4, OCT4, and JAG1. When compared to mock cells, no changes were observed in mRNA levels of ABCA2 and ABCB1 protein pumps with only a minor decrease of the ABCG2 pump in the aldehyde dehydrogenase 3A1-expressing cells. Also, the adhesion molecules EpCAM and CD49F were also found to be up-regulated in aldehyde dehydrogenase 3A1expressing cells. Taken together, ALDH3A1 confers a multi-modality resistance phenotype in MCF-7 cells associated with slower growth rate, increased clonogenic capacity, and altered gene expression profile, underlining its significance in cell homeostasis

Evaluating the Relationship between Circadian Rhythms and Sleep, Metabolic and Cardiovascular Disorders: Current Clinical Evidence in Human Studies

Circadian rhythms are generated by the circadian clock, a self-sustained internal timing system that exhibits 24-h rhythms in the body. Many metabolic, cellular, behavioral and physiological processes are regulated by the circadian clock in coordination with environmental cues. The present study is a comprehensive review of the currently existing evidence concerning the relationship between circadian rhythms and sleep, metabolic, and cardiovascular disorders. We thoroughly searched the online databases PubMed, Scopus, and Web of Science to find the existing clinical studies from the last twenty-three years (2000–2023). Circadian misalignment was found to be associated with an increase in the risk of metabolic disorders, cardiovascular diseases, and obesity, as well as inadequate sleep quality. In this review article, all the included studies had a strength protocol design and all of them were conducted on humans. However, the most common limitations of them were the small sample size and the short time of the intervention. In conclusion, managing the factors that disrupt the optimal function of central and peripheral clocks can help to reduce the risk of metabolic and cardiovascular diseases, improving also sleep quality. Future studies should further explore the underlying mechanisms of the interconnections between circadian clocks and sleep, metabolic, and cardiovascular disorders. This may provide new opportunities for advance chronotherapy 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

Super-Resolution Contrast Enhanced Ultrasound Methodology for the Identification of in-Vivo Vascular Dynamics in 2D

\u3cp\u3eObjectives The aim of this study was to provide an ultrasound-based super-resolution methodology that can be implemented using clinical 2-dimensional ultrasound equipment and standard contrast-enhanced ultrasound modes. In addition, the aim is to achieve this for true-to-life patient imaging conditions, including realistic examination times of a few minutes and adequate image penetration depths that can be used to scan entire organs without sacrificing current super-resolution ultrasound imaging performance. Methods Standard contrast-enhanced ultrasound was used along with bolus or infusion injections of SonoVue (Bracco, Geneva, Switzerland) microbubble (MB) suspensions. An image analysis methodology, translated from light microscopy algorithms, was developed for use with ultrasound contrast imaging video data. New features that are tailored for ultrasound contrast image data were developed for MB detection and segmentation, so that the algorithm can deal with single and overlapping MBs. The method was tested initially on synthetic data, then with a simple microvessel phantom, and then with in vivo ultrasound contrast video loops from sheep ovaries. Tracks detailing the vascular structure and corresponding velocity map of the sheep ovary were reconstructed. Images acquired from light microscopy, optical projection tomography, and optical coherence tomography were compared with the vasculature network that was revealed in the ultrasound contrast data. The final method was applied to clinical prostate data as a proof of principle. Results Features of the ovary identified in optical modalities mentioned previously were also identified in the ultrasound super-resolution density maps. Follicular areas, follicle wall, vessel diameter, and tissue dimensions were very similar. An approximately 8.5-fold resolution gain was demonstrated in vessel width, as vessels of width down to 60 μm were detected and verified (λ = 514 μm). Best agreement was found between ultrasound measurements and optical coherence tomography with 10% difference in the measured vessel widths, whereas ex vivo microscopy measurements were significantly lower by 43% on average. The results were mostly achieved using video loops of under 2-minute duration that included respiratory motion. A feasibility study on a human prostate showed good agreement between density and velocity ultrasound maps with the histological evaluation of the location of a tumor. Conclusions The feasibility of a 2-dimensional contrast-enhanced ultrasound-based super-resolution method was demonstrated using in vitro, synthetic and in vivo animal data. The method reduces the examination times to a few minutes using state-of-the-art ultrasound equipment and can provide super-resolution maps for an entire prostate with similar resolution to that achieved in other studies.\u3c/p\u3