12 resultados para Aggressiveness in adolescence

em AMS Tesi di Dottorato - Alm@DL - Università di Bologna


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Zyxin is a phosphoprotein localized at the focal adhesions and on the actin stress fibres, where it regulates the cytoskeleton organization. In addition, zyxin can shift into the nucleus and modulates the gene expression, affecting key cellular processes. Consequently, zyxin is as a crucial factor in the malignancy of several cancers, like Ewing sarcoma (EWS). EWS is a rare tumour of the bones, affecting children and adolescents. The main features of EWS are the presence of a chimeric transcriptional factor, EWS-FLI1 and the high expression of CD99, a glycoprotein necessary for the maintenance of the malignant phenotype. Triggering of CD99 with specific antibodies causes massive cell death, an effect that requires zyxin presence. In EWS zyxin is repressed by EWS-FLI1 and its forced re-expression counteracts the malignant phenotype. In this work we decided to deepen our knowledge on how zyxin affects EWS malignancy. We proved that zyxin is a negative regulator of cell migration, survival and growth in anchorage-independent conditions, confirming the tumour suppressor role of zyxin. Then we focused on the relation between CD99 and zyxin. Loss of function of CD99, by engagement with specific antibodies or use of shRNA, increases zyxin levels and promotes its nuclear translocation. Here, we observed that zyxin impairs the transcriptional activity of the Glioma associated oncogene 1 (Gli1), a member of the Hedgehog signalling pathway, which has a relevant oncogenic function in EWS. To support these evidences, we also reported that the loss of function of CD99 inhibits, trough zyxin mediation, the expression of Gli1 up-regulated target genes, such as NKX2-2, PTCH1 and cyclins, whilst enhances the expression of its down-regulated target GAS1. In conclusion, we presented a more accurate depiction of zyxin role in EWS, which in the future could be further developed in hope to offer new therapeutic approaches.

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Glioblastoma is the most malignant brain tumor in adults. The standard care of treatment is tumor resection, radiotherapy, and chemotherapy. Despite these invasive therapeutic approaches, glioblastoma prognosis remains unchanged. Therefore, a better understanding of the molecular mechanisms driving tumor transformation is needed to uncover novel therapeutic strategies. Several studies have shown the significance of lipid signaling and phospholipases (PLCs) in the regulation of different mechanisms in the central nervous system as well as in glioblastoma pathogenesis. This work suggests a potential role of PLCβ1 in the maintenance of a less aggressive phenotype of the tumor. Indeed, it was demonstrated that PLCβ1 gene was relatively less expressed in glioblastoma patients compared to their healthy/low-grade counterparts. Moreover, PLCβ1 silencing, in both immortalized and primary cell lines, led to increased cell migration, invasion, proliferation, cell survival and induced the upregulation of mesenchymal markers and metalloproteinases. Moreover, PLCγ1, another abundant PLC isoform in the brain, has been identified as a key element for the aggressiveness of glioblastoma. Data collected on patients’ biopsies and engineered cell models, suggested a strong correlation between PLCγ1 expression level and the acquisition of a more aggressive tumor phenotype. Finally, this trend was further probed using patient-derived glioblastoma stem cells (GSCs), which are a specific tumor population that drives aggressiveness, resistance, and recurrence in glioblastoma. GSCs analysis on the transcriptomic profiles confirmed that PLCγ1 downregulation modulated positively the activation of pathways that negatively regulate cell motility and migration and led to a decreased expression of genes involved in cancer development and progression. Taken together, these data highlight the importance of further investigating phospholipases as potential prognostic biomarkers and targets in the development of new therapeutic strategies for glioblastoma.

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In the first chapter, we consider the joint estimation of objective and risk-neutral parameters for SV option pricing models. We propose a strategy which exploits the information contained in large heterogeneous panels of options, and we apply it to S&P 500 index and index call options data. Our approach breaks the stochastic singularity between contemporaneous option prices by assuming that every observation is affected by measurement error. We evaluate the likelihood function by using a MC-IS strategy combined with a Particle Filter algorithm. The second chapter examines the impact of different categories of traders on market transactions. We estimate a model which takes into account traders’ identities at the transaction level, and we find that the stock prices follow the direction of institutional trading. These results are carried out with data from an anonymous market. To explain our estimates, we examine the informativeness of a wide set of market variables and we find that most of them are unambiguously significant to infer the identity of traders. The third chapter investigates the relationship between the categories of market traders and three definitions of financial durations. We consider trade, price and volume durations, and we adopt a Log-ACD model where we include information on traders at the transaction level. As to trade durations, we observe an increase of the trading frequency when informed traders and the liquidity provider intensify their presence in the market. For price and volume durations, we find the same effect to depend on the state of the market activity. The fourth chapter proposes a strategy to express order aggressiveness in quantitative terms. We consider a simultaneous equation model to examine price and volume aggressiveness at Euronext Paris, and we analyse the impact of a wide set of order book variables on the price-quantity decision.

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L’obiettivo del presente progetto di ricerca era determinare se l’utilizzo non clinico del simulatore d’alba (un dispositivo che emette luce in graduale aumento prima del risveglio), basato su specifiche conoscenze cronobiologiche, potesse ridurre alcune delle conseguenze del social jetlag, in studenti di scuola secondaria di secondo grado. A tal fine, sono stati valutati gli effetti del simulatore d’alba su tono dell’umore (valutato soggettivamente tramite la Global and Vigor Affect Scale-GVA), livelli di attivazione (valutati soggettivamente tramite la GVA), qualità/quantità di sonno (valutate oggettivamente e soggettivamente tramite attigrafia e Mini Sleep Questionnaire-MSQ), architettura del sonno (valutata oggettivamente tramite Zeo®) ed efficienza dei tre network attentivi (alerting, orienting ed executive), valutata oggettivamente tramite l’Attention Network Test (ANT). In totale, hanno preso parte alla ricerca 56 adolescenti (24 femmine e 32 maschi), frequentanti due istituti di scuola secondaria di secondo grado nella città di Cesena, la cui età media era di 17.68 anni (range d’età 15-20 anni). Ad ogni studente è stata richiesta una partecipazione di 5 settimane consecutive ed il disegno di ricerca prevedeva 3 condizioni sperimentali: baseline, simulatore d’alba e controllo. All’MSQ, in seguito all’utilizzo del simulatore d’alba, sono state osservate una minore percezione di sonnolenza diurna, una frequenza inferiore di risvegli notturni ed una riduzione del numero di partecipanti che presentavano una cattiva qualità della veglia. All’ANT, è stato documentato un significativo miglioramento dell’efficienza del network attentivo dell’alerting, successivo all’impiego del simulatore d’alba, dovuto ad una maggiore reattività dei partecipanti in seguito alla comparsa del double cue, che anticipava la presentazione del target (freccia centrale di cui i partecipanti dovevano giudicare la direzione). Tali risultati convergono nell’evidenziare la capacità del simulatore d’alba di esercitare un effetto attivante/stimolante, mostrando dunque come esso possa essere considerato uno strumento potenzialmente utilizzabile quale contromisura al social jetlag in adolescenza.

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This doctoral thesis presents a project carried out in secondary schools located in the city of Ferrara with the primary objective of demonstrating the effectiveness of an intervention based on Well-Being Therapy (Fava, 2016) in reducing alcohol use and improving lifestyles. In the first part (chapters 1-3), an introduction on risky behaviors and unhealthy lifestyle in adolescence is presented, followed by an examination of the phenomenon of binge drinking and of the concept of psychological well-being. In the second part (chapters 4-6), the experimental study is presented. A three-arm cluster randomized controlled trial including three test periods was implemented. The study involved eleven classes that were randomly assigned to receive well-being intervention (WBI), lifestyle intervention (LI) or not receive intervention (NI). Results were analyzed by linear mixed model and mixed-effects logistic regression with the aim to test the efficacy of WBI in comparison with LI and NI. AUDIT-C total score increased more in NI in comparison with WBI (p=0.008) and LI (p=0.003) at 6-month. The odds to be classified as at-risk drinker was lower in WBI (OR 0.01; 95%CI 0.01–0.14) and LI (OR 0.01; 95%CI 0.01–0.03) than NI at 6-month. The odds to use e-cigarettes at 6-month (OR 0.01; 95%CI 0.01–0.35) and cannabis at post-test (OR 0.01; 95%CI 0.01–0.18) were less in WBI than NI. Sleep hours at night decreased more in NI than in WBI (p = 0.029) and LI (p = 0.006) at 6-month. Internet addiction scores decreased more in WBI (p = 0.003) and LI (p = 0.004) at post-test in comparison with NI. Conclusions about the obtained results, limitations of the study, and future implications are discussed. In the seventh chapter, the data of the project collected during the pandemic are presented and compared with those from recent literature.

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The current studies assessed the role of trait anger and anger expression styles on risk decision-making in adulthood, adolescence and childhood. In the first experiment 158 adults completed the STAXI-2 and an inventory consisting of a battery of hypothetical everyday decision-making scenarios. Participants were also asked to evaluate the perception of risk for each chosen option and some contextual characteristics, that are familiarity and salience for each scenario. The study provides evidence for a relationship between individual differences in the tendency to feel and express anger and risky decisions and for mediation effects of familiarity and salience appraisals. Moreover, results indicated that trait anger was predictive of risk perception and they provide evidence for a positive relationship between risk decision-making and risk perception. In the second study, we examined the relationship between specific components of anger (i.e., cognitive, affective and behavioural) and risk decision-making in adolescents. 101 subjects completed specific tasks, measuring risk decision-making, assessed using hypothetical choice scenarios, and anger, evaluated through the STAXI-CA and the MSAI-R. Results showed that adolescents higher on hostility, anger experience and destructive expression, make more risky decisions in everyday life situations. Moreover, regression analyses indicated that destructive expression of anger and hostility were predictive of adolescents’ risky decisions. In the third experiment, 104 children completed three tasks: the STAXI-CA, the MSAI-R and a task measuring risk decision-making in everyday situations. Subjects were also asked to evaluate the degree of danger, benefit, fun and fear perceived for each risky choice. Analyses indicated that: (a) risk decision-making was predicted by both trait anger and outward expression of anger; (b) destructive expression o anger was predictive of children’s risky decisions; (c) appraisal of danger fully mediated the relation between trait anger and risk; (d) perceptions of benefit, scare and fun partially mediated the relationship between trait anger and risk; and (e) appraisal of danger partially mediated the relationship between outward expression of anger and risk decision-making. The results provide evidence for a relationship between dispositional anger and risk decision-making during childhood, suggesting a possible explanation of the mechanisms below. In particular, risk decision-making can be viewed as the output of cognitive and emotive processes, linked to dispositional anger that leads children to be amused, optimistic and fearless in potentially risky situations. These findings substantiate the importance of incorporating cognitive and emotive factors in theories that seek to explain the relationship between personality traits and risk decision making across a broad range of age.

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Cyclooxygenase-2/Carbonic anhydrase-IX up-regulation promotes invasive potential and hypoxia survival in colorectal cancer cells Purpose: Cyclooxygenase-2 (COX-2) is a major mediator of inflammation, playing a pivotal role in colorectal carcinogenesis. Hypoxia is an universal hallmark of solid tumour in vivo. This investigation was prompted by the observation that in colorectal cancer cells the expression of COX-2 protein is positively correlated with that of the hypoxia survival gene Carbonic Anhydrase-IX (CA-IX). Experimental Design: Since COX-2 gene expression and activity is increased in hypoxia, and that CA-IX is expressed also in normoxia in colorectal cancer cells, we tested the hypothesis that COX-2 activity in normoxia, as well as in hypoxia may be functionally linked to that of CA-IX gene. We investigated the role of COX-2 and CA-IX in colorectal cancer cell lines. In this regard, we performed RNA interference to knockdown COX-2 gene in vitro and immunohistochemistry to evaluate the protein expression of COX-2 and CA-IX in human colon cancer tissue specimens ex vivo. Results: We found that COX-2, by PGE2 production, controls CA-IX gene expression in an ERK dependent manner. In line with this finding, we also showed that the COX-2 inhibition by a specific short harpin COX-2 RNA (shCOX-2) or by a specific drug (SC-236), down-regulated CA-IX expression in colon cancer cells. We then exposed colon cancer cells to hypoxia stimuli and found that COX-2/CA-IX interplay promoted hypoxia survival. Moreover, we also report that COX-2/CA-IX interplay triggers Matrix Metalloproteinase 2/9 (MMP-2/9) activation and enhances the invasiveness of colorectal cancer cells. Thus given our above observations, we found that CA-IX and COX-2 protein expressions correlate with more aggressive stage colorectal cancer tissues ex vivo. Conclusions: Taken together these data indicate that COX-2/CA-IX interplay promotes an aggressive phenotype (hypoxia survival and invasiveness) which can be modulated in vitro by COX-2 selective inhibition and which may play a role in determining the biological aggressiveness of colorectal tumours. Moreover, in vitro and ex vivo data also suggest that the signatures of inflammation (COX-2) and hypoxia (CA-IX) may be difficult to be disentangled in colon cancer, being both responsible for the up-regulation of the same pathways.

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Emotional Intelligence (EI) has increasingly gained widespread popularity amongst both lay people and scientists in a wide range of contexts and across several research areas. In spite of rigorous inquiry into its applications in educational, social, health and clinical settings, substantial disagreement exists regarding the definition of EI, with respect to both terminology and operationalizations. Actually, there is a consensus about a conceptual distinction between Trait EI, or trait emotional self-efficacy (Petrides & Furnham, 2001), and Ability EI, or cognitive-emotional ability (Mayer & Salovey, 1997). Trait EI is measured via self-report questionnaires, whereas Ability EI is assessed via maximum performance tests. Moreover, EI is the broadest of the emotional constructs, and it subsumes various constructs, as Emotional Awareness (Lane & Schwartz, 1987). To date, EI research has focused primarily on adults, with fewer studies conducted with child samples. The aim of the present study is to investigate the role of different models of EI in childhood and early adolescence (N = 670; 353 females; Mage= 10.25 years ; SD = 1.57). In addition, a further goal is to evaluate the relationship of each construct with personality, non verbal cognitive intelligence, school performance, peer relationships, and affective disorders (anxiety and depression). Results shows significant correlations between Trait EI and Emotional Awareness, whereas Trait and Ability EI appear as independent constructs. We also found significant positive associations between age and Ablity EI and Emotional Awareness (although with add of verbal productivity), while gender differences emerged in favour of females in all EI-related measures. The results provide evidence that Trait EI is partially determined by all of the Big Five personality dimensions, but independent of cognitive ability. Finally, the present study highlights the role of EI on social interactions, school performance and, especially, a negative relationship between Trait EI and psychopathology.

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For some study cases (the Cathedral of Modena, Italy, XII-XIV century; the Ducal Palace in Mantua, Italy, XVI century; the church of San Francesco in Fano, Italy, XIV-XIX century), considered as representative of the use of natural and artificial stones in historical architecture, the complex interaction between environ-mental aggressiveness, materials’ microstructural characteristics and degradation was investigated. From the results of such analyses, it was found that materials microstructure plays a fundamental role in the actual extent to which weathering mechanisms affect natural and artificial stones. Consequently, the need of taking into account the important role of material microstructure, when evaluating the environmental aggressiveness to natural and artificial stones, was highlighted. Therefore, a possible quantification of the role of microstructure on the resistance to environmental attack was investigated. By exposing stone samples, with significantly different microstructural features, to slightly acidic aqueous solutions, simulating clean and acid rain, a good correlation between weight losses and the product of carbonate content and specific surface area (defined as the “vulnerable specific surface area”) was found. Alongside the evaluation of stone vulnerability, the development of a new consolidant for weathered carbonate stones was undertaken. The use of hydroxya-patite, formed by reacting the calcite of the stone with an aqueous solution of di-ammonium hydrogen phosphate, was found to be a promising consolidating tech-nique for carbonates stones. Indeed, significant increases in the mechanical prop-erties can be achieved after the treatment, which has the advantage of simply con-sisting in a non-hazardous aqueous solution, able to penetrate deeply into the stone (> 2 cm) and bring significant strengthening after just 2 days of reaction. Furthermore, the stone sorptivity is not eliminated after treatment, so that water and water vapor exchanges between the stone and the environment are not com-pletely blocked.

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Scopo del nostro lavoro è stato descrivere ed inquadrare gli aspetti psico-comportamentali e la qualità di vita della narcolessia in età evolutiva. Metodi: Abbiamo pertanto disegnato uno studio caso-controllo comprendente 30 pazienti narcolettici, 39 epilettici, e 39 controlli sani, appaiati per sesso e età. Risultati: La nostra popolazione di bambini e adolescenti affetti da narcolessia mostra un aumento delle problematiche internalizzanti. I due gruppi patologici hanno in comune punteggi più elevati rispetto ai controlli per i disturbi d’ansia, le difficoltà attentive e di socializzazione, i disturbi oppositivo-provocatori. Ciò che distingue, invece, i pazienti narcolettici, sono gli aspetti di ritiro e depressione, la tendenza alla somatizzazione, i problemi del pensiero ed i disturbi affettivi. Fattori di rischio psicopatologici per i giovani narcolettici sono risultati essere l’esordio precoce, il ritardo diagnostico, il sonno notturno disturbato, la minor latenza di sonno all’addormentamento, un maggior numero di SOREMP all’MSLT. Dall’altro lato la terapia farmacologica, un maggior numero di sonnellini spontanei e la durata di malattia, sembrano influenzare positivamente l’evoluzione comportamentale. La salute psicosociale dei giovani narcolettici, inoltre, risulta essere peggiore rispetto ai controlli sani, mentre la salute fisica non mostra differenze. I problemi internalizzanti influenzano negativamente tutti gli ambiti della salute di questi ragazzi, mentre la durata di malattia sembra migliorare il funzionamento scolastico. Conclusioni: Il nostro lavoro conferma che i giovani narcolettici presentano un maggior rischio psicopatologico sia rispetto ai controlli sani sia rispetto un’altra patologia neurologica cronica. Se da un lato alcuni aspetti comportamentali possono essere giustificati come una reazione adattativa verso una patologia neurologica invalidante, dall’altro un quadro distimico caratterizzato da ritiro e lamentele somatiche, sembra essere tipico dei bambini ed adolescenti narcolettici.

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Fusarium Head Blight (FHB) is a worldwide cereal disease responsible of significant yield reduction, inferior grain quality, and mycotoxin accumulation. Fusarium graminearum and F. culmorum are the prevalent causal agents. FHB has been endemic in Italy since 1995, while there are no records about its presence in Syria. Forty-eight and forty-six wheat kernel samples were collected from different localities and analyzed for fungal presence and mycotoxin contamination. Fusarium strains were identified morphologically but the molecular confirmation was performed only for some species. Further differentiation of the chemotypes for trichothecene synthesis by F. graminearum and F. culmorum strains was conducted by PCR assays. Fusarium spp. were present in 62.5% of Syrian samples. 3Acetyl-Deoxynivalenol and nivalenol chemotypes were found in F. culmorum whilst all F. graminearum strains belonged to NIV chemotype. Italian samples were infected with Fusarium spp for 67.4%. 15Ac-DON was the prevalent chemotype in F. graminearum, while 3Ac-DON chemotype was detected in F. culmorum. The 60 Syrian Fusarium strains tested for mycotoxin production by HPLC-MS/MS have shown the prevalence of zearalenone while the emerging mycotoxins were almost absent. The analysis of the different Syrian and Italian samples of wheat kernels for their mycotoxin content showed that Syrian kernels were mainly contaminated with storage mycotoxins, aflatoxins and ochratoxin whilst Italian grains with mainly Fusarium mycotoxins. The aggressiveness of several Syrian F. culmorum isolates was estimated using three different assays: floret inoculation in growth chamber, ear inoculation in the field and a validated new Petri-dish test. The study of the behaviour of different Syrian wheat cultivars, grown under different conditions, has revealed that Jory is a FHB Syrian tolerant cultivar. This is the first study in Syria on Fusarium spp. associated to FHB, Fusarium mycotoxin producers and grain quality.

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Il lavoro svolto in questa tesi si propone di valutare la variabilità della composizione corporea nell’infanzia e nell’adolescenza, con particolare attenzione alla transizione dalla prima alla seconda, in relazione allo stato nutrizionale ed agli stili di vita. Lo studio è stato condotto eseguendo misure antropometriche presso scuole primarie e secondarie di Bologna. Sono stati analizzati inoltre dati acquisiti a partire dal 2004. Il campione analizzato comprende 3546 soggetti di età compresa tra 6 anni e 14 anni. In particolare sono state analizzate le principali misurazioni utili per il calcolo della composizione corporea, evidenziando i parametri antropometrici principali quali BMI, circonferenza vita, WHR, %F e FFM. Questi caratteri sono stati quindi messi in relazione con le informazioni inerenti l’attività sportiva extrascolastica e gli stili di vita dei soggetti esaminati. L’analisi trasversale delle principali caratteristiche antropometriche ha fornito un interessante panorama della situazione italiana e del nord Italia; lo studio longitudinale delle variabili antropometriche permette di ottenere un quadro aggiornato dei principali incrementi delle misure corporee. La valutazione della variabilità della composizione corporea in relazione all’attività sportiva e allo stile di vita durante il processo di accrescimento ha indicato come abitudini sane e propensione all’attività motoria sono sicuramente in grado di apportare miglioramenti nella modificazione della composizione corporea nel processo evolutivo specialmente se somministrate con modalità adeguate all’età e alle esigenze individuali. Questi aspetti sono certamente rilevanti e complessi, sarebbe infatti interessante in prospettiva futura riuscire ad indagare ancora più dettagliatamente sull’interazione tra i fattori che determinano e modificano la composizione corporea in un periodo della vita così particolare come la transizione dall’infanzia all’adolescenza.