11 resultados para after MacLennan et al. (2002)

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


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The organization of the nervous and immune systems is characterized by obvious differences and striking parallels. Both systems need to relay information across very short and very long distances. The nervous system communicates over both long and short ranges primarily by means of more or less hardwired intercellular connections, consisting of axons, dendrites, and synapses. Longrange communication in the immune system occurs mainly via the ordered and guided migration of immune cells and systemically acting soluble factors such as antibodies, cytokines, and chemokines. Its short-range communication either is mediated by locally acting soluble factors or transpires during direct cell–cell contact across specialized areas called “immunological synapses” (Kirschensteiner et al., 2003). These parallels in intercellular communication are complemented by a complex array of factors that induce cell growth and differentiation: these factors in the immune system are called cytokines; in the nervous system, they are called neurotrophic factors. Neither the cytokines nor the neurotrophic factors appear to be completely exclusive to either system (Neumann et al., 2002). In particular, mounting evidence indicates that some of the most potent members of the neurotrophin family, for example, nerve growth factor (NGF) and brainderived neurotrophic factor (BDNF), act on or are produced by immune cells (Kerschensteiner et al., 1999) There are, however, other neurotrophic factors, for example the insulin-like growth factor-1 (IGF-1), that can behave similarly (Kermer et al., 2000). These factors may allow the two systems to “cross-talk” and eventually may provide a molecular explanation for the reports that inflammation after central nervous system (CNS) injury has beneficial effects (Moalem et al., 1999). In order to shed some more light on such a cross-talk, therefore, transcription factors modulating mu-opioid receptor (MOPr) expression in neurons and immune cells are here investigated. More precisely, I focused my attention on IGF-I modulation of MOPr in neurons and T-cell receptor induction of MOPr expression in T-lymphocytes. Three different opioid receptors [mu (MOPr), delta (DOPr), and kappa (KOPr)] belonging to the G-protein coupled receptor super-family have been cloned. They are activated by structurallyrelated exogenous opioids or endogenous opioid peptides, and contribute to the regulation of several functions including pain transmission, respiration, cardiac and gastrointestinal functions, and immune response (Zollner and Stein 2007). MOPr is expressed mainly in the central nervous system where it regulates morphine-induced analgesia, tolerance and dependence (Mayer and Hollt 2006). Recently, induction of MOPr expression in different immune cells induced by cytokines has been reported (Kraus et al., 2001; Kraus et al., 2003). The human mu-opioid receptor gene (OPRM1) promoter is of the TATA-less type and has clusters of potential binding sites for different transcription factors (Law et al. 2004). Several studies, primarily focused on the upstream region of the OPRM1 promoter, have investigated transcriptional regulation of MOPr expression. Presently, however, it is still not completely clear how positive and negative transcription regulators cooperatively coordinate cellor tissue-specific transcription of the OPRM1 gene, and how specific growth factors influence its expression. IGF-I and its receptors are widely distributed throughout the nervous system during development, and their involvement in neurogenesis has been extensively investigated (Arsenijevic et al. 1998; van Golen and Feldman 2000). As previously mentioned, such neurotrophic factors can be also produced and/or act on immune cells (Kerschenseteiner et al., 2003). Most of the physiologic effects of IGF-I are mediated by the type I IGF surface receptor which, after ligand binding-induced autophosphorylation, associates with specific adaptor proteins and activates different second messengers (Bondy and Cheng 2004). These include: phosphatidylinositol 3-kinase, mitogen-activated protein kinase (Vincent and Feldman 2002; Di Toro et al. 2005) and members of the Janus kinase (JAK)/STAT3 signalling pathway (Zong et al. 2000; Yadav et al. 2005). REST plays a complex role in neuronal cells by differentially repressing target gene expression (Lunyak et al. 2004; Coulson 2005; Ballas and Mandel 2005). REST expression decreases during neurogenesis, but has been detected in the adult rat brain (Palm et al. 1998) and is up-regulated in response to global ischemia (Calderone et al. 2003) and induction of epilepsy (Spencer et al. 2006). Thus, the REST concentration seems to influence its function and the expression of neuronal genes, and may have different effects in embryonic and differentiated neurons (Su et al. 2004; Sun et al. 2005). In a previous study, REST was elevated during the early stages of neural induction by IGF-I in neuroblastoma cells. REST may contribute to the down-regulation of genes not yet required by the differentiation program, but its expression decreases after five days of treatment to allow for the acquisition of neural phenotypes. Di Toro et al. proposed a model in which the extent of neurite outgrowth in differentiating neuroblastoma cells was affected by the disappearance of REST (Di Toro et al. 2005). The human mu-opioid receptor gene (OPRM1) promoter contains a DNA sequence binding the repressor element 1 silencing transcription factor (REST) that is implicated in transcriptional repression. Therefore, in the fist part of this thesis, I investigated whether insulin-like growth factor I (IGF-I), which affects various aspects of neuronal induction and maturation, regulates OPRM1 transcription in neuronal cells in the context of the potential influence of REST. A series of OPRM1-luciferase promoter/reporter constructs were transfected into two neuronal cell models, neuroblastoma-derived SH-SY5Y cells and PC12 cells. In the former, endogenous levels of human mu-opioid receptor (hMOPr) mRNA were evaluated by real-time PCR. IGF-I upregulated OPRM1 transcription in: PC12 cells lacking REST, in SH-SY5Y cells transfected with constructs deficient in the REST DNA binding element, or when REST was down-regulated in retinoic acid-differentiated cells. IGF-I activates the signal transducer and activator of transcription-3 (STAT3) signaling pathway and this transcription factor, binding to the STAT1/3 DNA element located in the promoter, increases OPRM1 transcription. T-cell receptor (TCR) recognizes peptide antigens displayed in the context of the major histocompatibility complex (MHC) and gives rise to a potent as well as branched intracellular signalling that convert naïve T-cells in mature effectors, thus significantly contributing to the genesis of a specific immune response. In the second part of my work I exposed wild type Jurkat CD4+ T-cells to a mixture of CD3 and CD28 antigens in order to fully activate TCR and study whether its signalling influence OPRM1 expression. Results were that TCR engagement determined a significant induction of OPRM1 expression through the activation of transcription factors AP-1, NF-kB and NFAT. Eventually, I investigated MOPr turnover once it has been expressed on T-cells outer membrane. It turned out that DAMGO induced MOPr internalisation and recycling, whereas morphine did not. Overall, from the data collected in this thesis we can conclude that that a reduction in REST is a critical switch enabling IGF-I to up-regulate human MOPr, helping these findings clarify how human MOPr expression is regulated in neuronal cells, and that TCR engagement up-regulates OPRM1 transcription in T-cells. My results that neurotrophic factors a and TCR engagement, as well as it is reported for cytokines, seem to up-regulate OPRM1 in both neurons and immune cells suggest an important role for MOPr as a molecular bridge between neurons and immune cells; therefore, MOPr could play a key role in the cross-talk between immune system and nervous system and in particular in the balance between pro-inflammatory and pro-nociceptive stimuli and analgesic and neuroprotective effects.

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In order to improve the animal welfare, the Council Directive 1999/74/EC (defining minimum standards for the welfare of laying hens) will ban conventional cage systems since 2012, in favour of enriched cages or floor systems. As a consequence an increased risk of bacterial contamination of eggshell is expected (EFSA, 2005). Furthermore egg-associated salmonellosis is an important public health problem throughout the world (Roberts et al., 1994). In this regard the introduction of efficient measures to reduce eggshell contamination by S. Enteritidis or other bacterial pathogens, and thus to prevent any potential or additional food safety risk for Human health, may be envisaged. The hot air pasteurization can be a viable alternative for the decontamination of the surface of the egg shell. Few studies have been performed on the decontamination power of this technique on table eggs (Hou et al, 1996; James et al., 2002). The aim of this study was to develop innovative techniques to remove surface contamination of shell eggs by hot air under natural or forced convection. Initially two simplified finite element models describing the thermal interaction between the air and egg were developed, respectively for the natural and forced convection. The numerical models were validated using an egg simulant equipped by type-K thermocouple (Chromel/Alumel). Once validated, the models allowed the selection of a thermal cycle with an inner temperature always lower than 55°C. Subsequently a specific apparatus composed by two hot air generators, one cold air generator and rolling cylinder support, was built to physically condition the eggs. The decontamination power of the thermal treatments was evaluated on shell eggs experimentally inoculated with either Salmonella Enteritidis, Escherichia coli, Listeria monocytogenes and on shell eggs containing only the indigenous microflora. The applicability of treatments was further evaluated by comparing quality traits of treated and not treated eggs immediately after the treatment and after 28 days of storage at 20°C. The results showed that the treatment characterized by two shots of hot air at 350°C for 8 sec, spaced by a cooling interval of 32 (forced convection), reduce the bacterial population of more than 90% (Salmonella enteritidis and Listeria monocytogenes). No statistically significant results were obtained comparing E. coli treated and not treated eggs as well as indigenous microflora treated and not treated eggs. A reduction of 2.6 log was observed on Salmonella enteritidis load of eggs immediately after the treatment in oven at 200°C for 200 minutes (natural convection). Furthermore no detrimental effects on quality traits of treated eggs were recorded. These results support the hot air techniques for the surface decontamination of table eggs as an effective industrial process.

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It was decided to carry out a morphological and molecular characterization of the Italian Alternaria isolatescollected from apple , and evaluate their pathogenicity and subsequently combining the data collected. The strain collection (174 isolates) was constructed by collecting material (received from extension service personnel) between June and August of 2007, 2008, and 2009. A Preliminary bioassays were performed on detached plant materials (fruit and leaf wounded and unwounded), belonging to the Golden cultivar, with two different kind of inoculation (conidial suspension and conidial filtrate). Symptoms were monitored daily and a value of pathogenicity score (P.S.) was assigned on the basis of the diameter of the necrotic area that developed. On the basis of the bioassays, the number of isolates to undergo further molecular analysis was restricted to a representative set of single spore strains (44 strains). Morphological characteristics of the colony and sporulation pattern were determined according to previous systematic work on small-spored Alternaria spp. (Pryor and Michaelides, 2002 and Hong et al., 2006). Reference strains (Alternaria alternata, Alternaria tenuissima, Alternaria arborescens and four Japanese strains of Alternaria alternata mali pathotype), used in the study were kindly provided by Prof. Barry Pryor, who allows a open access to his own fungal collection. Molecular characterization was performed combining and comparing different data sets obtained from distinct molecular approach: 1) investigation of specific loci and 2) fingerprinting based on diverse randomly selected polymorphic sites of the genome. As concern the single locus analysis, it was chosen to sequence the EndoPG partial gene and three anonymous region (OPA1-3, OPA2- and OPa10-2). These markers has revealed a powerful tool in the latter systematic works on small-spored Alternaria spp. In fact, as reported in literature small-spored Alternaria taxonomy is complicated due to the inability to resolve evolutionary relationships among the taxa because of the lack of variability in the markers commonly used in fungi systematic. The three data set together provided the necessary variation to establish the phylogenetic relationships among the Italian isolates of Alternaria spp. On Italian strains these markers showed a variable number of informative sites (ranging from 7 for EndoPg to 85 for OPA1-3) and the parsimony analysis produced different tree topologies all concordant to define A. arborescens as a mophyletic clade. Fingerprinting analysis (nine ISSR primers and eight AFLP primers combination) led to the same result: a monophyleic A. arborescens clade and one clade containing both A. tenuissima and the A. alternata strains. This first attempt to characterize Italian Alternaria species recovered from apple produced concordant results with what was already described in a similar phylogenetic study on pistachio (Pryor and Michaelides, 2002), on walnut and hazelnut (Hong et al., 2006), apple (Kang et al., 2002) and citurus (Peever et al., 2004). Together with these studies, this research demonstrates that the three morphological groups are widely distributed and occupy similar ecological niches. Furthermore, this research suggest that these Alternaria species exhibit a similar infection pattern despite the taxonomic and pathogenic differences. The molecular characterization of the pathogens is a fundamental step to understanding the disease that is spreading in the apple orchards of the north Italy. At the beginning the causal agent was considered as Alteraria alternata (Marshall and Bertagnoll, 2006). Their preliminary studies purposed a pathogenic system related to the synthesis of toxins. Experimental data of our bioassays suggest an analogous hypothesis, considering that symptoms could be induced after inoculating plant material with solely the filtrate from pathogenic strains. Moreover, positive PCR reactions using AM-toxin gene specific primers, designed for identification of apple infecting Alternaria pathovar, led to a hypothesis that a host specific toxin (toxins) were involved. It remains an intriguing challenge to discover or not if the agent of the “Italian disease” is the same of the one previously typified as Alternaria mali, casual agent of the apple blotch disease.

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L’analisi del movimento umano ha come obiettivo la descrizione del movimento assoluto e relativo dei segmenti ossei del soggetto e, ove richiesto, dei relativi tessuti molli durante l’esecuzione di esercizi fisici. La bioingegneria mette a disposizione dell’analisi del movimento gli strumenti ed i metodi necessari per una valutazione quantitativa di efficacia, funzione e/o qualità del movimento umano, consentendo al clinico l’analisi di aspetti non individuabili con gli esami tradizionali. Tali valutazioni possono essere di ausilio all’analisi clinica di pazienti e, specialmente con riferimento a problemi ortopedici, richiedono una elevata accuratezza e precisione perché il loro uso sia valido. Il miglioramento della affidabilità dell’analisi del movimento ha quindi un impatto positivo sia sulla metodologia utilizzata, sia sulle ricadute cliniche della stessa. Per perseguire gli obiettivi scientifici descritti, è necessario effettuare una stima precisa ed accurata della posizione e orientamento nello spazio dei segmenti ossei in esame durante l’esecuzione di un qualsiasi atto motorio. Tale descrizione può essere ottenuta mediante la definizione di un modello della porzione del corpo sotto analisi e la misura di due tipi di informazione: una relativa al movimento ed una alla morfologia. L’obiettivo è quindi stimare il vettore posizione e la matrice di orientamento necessari a descrivere la collocazione nello spazio virtuale 3D di un osso utilizzando le posizioni di punti, definiti sulla superficie cutanea ottenute attraverso la stereofotogrammetria. Le traiettorie dei marker, così ottenute, vengono utilizzate per la ricostruzione della posizione e dell’orientamento istantaneo di un sistema di assi solidale con il segmento sotto esame (sistema tecnico) (Cappozzo et al. 2005). Tali traiettorie e conseguentemente i sistemi tecnici, sono affetti da due tipi di errore, uno associato allo strumento di misura e l’altro associato alla presenza di tessuti molli interposti tra osso e cute. La propagazione di quest’ultimo ai risultati finali è molto più distruttiva rispetto a quella dell’errore strumentale che è facilmente minimizzabile attraverso semplici tecniche di filtraggio (Chiari et al. 2005). In letteratura è stato evidenziato che l’errore dovuto alla deformabilità dei tessuti molli durante l’analisi del movimento umano provoca inaccuratezze tali da mettere a rischio l’utilizzabilità dei risultati. A tal proposito Andriacchi scrive: “attualmente, uno dei fattori critici che rallentano il progresso negli studi del movimento umano è la misura del movimento scheletrico partendo dai marcatori posti sulla cute” (Andriacchi et al. 2000). Relativamente alla morfologia, essa può essere acquisita, ad esempio, attraverso l’utilizzazione di tecniche per bioimmagini. Queste vengono fornite con riferimento a sistemi di assi locali in generale diversi dai sistemi tecnici. Per integrare i dati relativi al movimento con i dati morfologici occorre determinare l’operatore che consente la trasformazione tra questi due sistemi di assi (matrice di registrazione) e di conseguenza è fondamentale l’individuazione di particolari terne di riferimento, dette terne anatomiche. L’identificazione di queste terne richiede la localizzazione sul segmento osseo di particolari punti notevoli, detti repere anatomici, rispetto ad un sistema di riferimento solidale con l’osso sotto esame. Tale operazione prende il nome di calibrazione anatomica. Nella maggior parte dei laboratori di analisi del movimento viene implementata una calibrazione anatomica a “bassa risoluzione” che prevede la descrizione della morfologia dell’osso a partire dall’informazione relativa alla posizione di alcuni repere corrispondenti a prominenze ossee individuabili tramite palpazione. Attraverso la stereofotogrammetria è quindi possibile registrare la posizione di questi repere rispetto ad un sistema tecnico. Un diverso approccio di calibrazione anatomica può essere realizzato avvalendosi delle tecniche ad “alta risoluzione”, ovvero attraverso l’uso di bioimmagini. In questo caso è necessario disporre di una rappresentazione digitale dell’osso in un sistema di riferimento morfologico e localizzare i repere d’interesse attraverso palpazione in ambiente virtuale (Benedetti et al. 1994 ; Van Sint Jan et al. 2002; Van Sint Jan et al. 2003). Un simile approccio è difficilmente applicabile nella maggior parte dei laboratori di analisi del movimento, in quanto normalmente non si dispone della strumentazione necessaria per ottenere le bioimmagini; inoltre è noto che tale strumentazione in alcuni casi può essere invasiva. Per entrambe le calibrazioni anatomiche rimane da tenere in considerazione che, generalmente, i repere anatomici sono dei punti definiti arbitrariamente all’interno di un’area più vasta e irregolare che i manuali di anatomia definiscono essere il repere anatomico. L’identificazione dei repere attraverso una loro descrizione verbale è quindi povera in precisione e la difficoltà nella loro identificazione tramite palpazione manuale, a causa della presenza dei tessuti molli interposti, genera errori sia in precisione che in accuratezza. Tali errori si propagano alla stima della cinematica e della dinamica articolare (Ramakrishnan et al. 1991; Della Croce et al. 1999). Della Croce (Della Croce et al. 1999) ha inoltre evidenziato che gli errori che influenzano la collocazione nello spazio delle terne anatomiche non dipendono soltanto dalla precisione con cui vengono identificati i repere anatomici, ma anche dalle regole che si utilizzano per definire le terne. E’ infine necessario evidenziare che la palpazione manuale richiede tempo e può essere effettuata esclusivamente da personale altamente specializzato, risultando quindi molto onerosa (Simon 2004). La presente tesi prende lo spunto dai problemi sopra elencati e ha come obiettivo quello di migliorare la qualità delle informazioni necessarie alla ricostruzione della cinematica 3D dei segmenti ossei in esame affrontando i problemi posti dall’artefatto di tessuto molle e le limitazioni intrinseche nelle attuali procedure di calibrazione anatomica. I problemi sono stati affrontati sia mediante procedure di elaborazione dei dati, sia apportando modifiche ai protocolli sperimentali che consentano di conseguire tale obiettivo. Per quanto riguarda l’artefatto da tessuto molle, si è affrontato l’obiettivo di sviluppare un metodo di stima che fosse specifico per il soggetto e per l’atto motorio in esame e, conseguentemente, di elaborare un metodo che ne consentisse la minimizzazione. Il metodo di stima è non invasivo, non impone restrizione al movimento dei tessuti molli, utilizza la sola misura stereofotogrammetrica ed è basato sul principio della media correlata. Le prestazioni del metodo sono state valutate su dati ottenuti mediante una misura 3D stereofotogrammetrica e fluoroscopica sincrona (Stagni et al. 2005), (Stagni et al. 2005). La coerenza dei risultati raggiunti attraverso i due differenti metodi permette di considerare ragionevoli le stime dell’artefatto ottenute con il nuovo metodo. Tale metodo fornisce informazioni sull’artefatto di pelle in differenti porzioni della coscia del soggetto e durante diversi compiti motori, può quindi essere utilizzato come base per un piazzamento ottimo dei marcatori. Lo si è quindi utilizzato come punto di partenza per elaborare un metodo di compensazione dell’errore dovuto all’artefatto di pelle che lo modella come combinazione lineare degli angoli articolari di anca e ginocchio. Il metodo di compensazione è stato validato attraverso una procedura di simulazione sviluppata ad-hoc. Relativamente alla calibrazione anatomica si è ritenuto prioritario affrontare il problema associato all’identificazione dei repere anatomici perseguendo i seguenti obiettivi: 1. migliorare la precisione nell’identificazione dei repere e, di conseguenza, la ripetibilità dell’identificazione delle terne anatomiche e della cinematica articolare, 2. diminuire il tempo richiesto, 3. permettere che la procedura di identificazione possa essere eseguita anche da personale non specializzato. Il perseguimento di tali obiettivi ha portato alla implementazione dei seguenti metodi: • Inizialmente è stata sviluppata una procedura di palpazione virtuale automatica. Dato un osso digitale, la procedura identifica automaticamente i punti di repere più significativi, nella maniera più precisa possibile e senza l'ausilio di un operatore esperto, sulla base delle informazioni ricavabili da un osso digitale di riferimento (template), preliminarmente palpato manualmente. • E’ stato poi condotto uno studio volto ad indagare i fattori metodologici che influenzano le prestazioni del metodo funzionale nell’individuazione del centro articolare d’anca, come prerequisito fondamentale per migliorare la procedura di calibrazione anatomica. A tale scopo sono stati confrontati diversi algoritmi, diversi cluster di marcatori ed è stata valutata la prestazione del metodo in presenza di compensazione dell’artefatto di pelle. • E’stato infine proposto un metodo alternativo di calibrazione anatomica basato sull’individuazione di un insieme di punti non etichettati, giacenti sulla superficie dell’osso e ricostruiti rispetto ad un TF (UP-CAST). A partire dalla posizione di questi punti, misurati su pelvi coscia e gamba, la morfologia del relativo segmento osseo è stata stimata senza identificare i repere, bensì effettuando un’operazione di matching dei punti misurati con un modello digitale dell’osso in esame. La procedura di individuazione dei punti è stata eseguita da personale non specializzato nell’individuazione dei repere anatomici. Ai soggetti in esame è stato richiesto di effettuare dei cicli di cammino in modo tale da poter indagare gli effetti della nuova procedura di calibrazione anatomica sulla determinazione della cinematica articolare. I risultati ottenuti hanno mostrato, per quel che riguarda la identificazione dei repere, che il metodo proposto migliora sia la precisione inter- che intraoperatore, rispetto alla palpazione convenzionale (Della Croce et al. 1999). E’ stato inoltre riscontrato un notevole miglioramento, rispetto ad altri protocolli (Charlton et al. 2004; Schwartz et al. 2004), nella ripetibilità della cinematica 3D di anca e ginocchio. Bisogna inoltre evidenziare che il protocollo è stato applicato da operatori non specializzati nell’identificazione dei repere anatomici. Grazie a questo miglioramento, la presenza di diversi operatori nel laboratorio non genera una riduzione di ripetibilità. Infine, il tempo richiesto per la procedura è drasticamente diminuito. Per una analisi che include la pelvi e i due arti inferiori, ad esempio, l’identificazione dei 16 repere caratteristici usando la calibrazione convenzionale richiede circa 15 minuti, mentre col nuovo metodo tra i 5 e i 10 minuti.

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La variabilità genetica è un importante strumento per lo studio e la conservazione della biodiversità in specie rare e minacciate di estinzione. Durante il mio dottorato mi sono quindi occupata di mettere a punto diverse metodologie molecolari al fine di valutare la diversità genetica in due specie rare della flora italiana che presentano problematiche diverse e specifiche. I marcatori arbitrari RAPD e i marcatori semi-arbitrari ISSR sono stati utilizzati per valutare la diversità genetica in Quercus crenata Lam. e per confermare l’ipotesi della sua origine ibridogena dalle due specie presunte parentali Quercus cerris L. e Quercus suber L., essendo Q. crenata presente in Italia settentrionale dove Q. suber è attualmente assente. I marcatori SSR o microsatelliti sono invece stati messi a punto su una specie a rischio di estinzione, endemica dell’Appennino Tosco-Emiliano, Primula apennina Widmer, applicando una metodologia specifica, basata sulla costruzione di una libreria genomica arricchita per l’isolamento di primer specifici. I marcatori RAPD e ISSR, utilizzati su un totale di 85 campioni, hanno mostrato alti livelli di diversità molecolare entro le specie studiate, eccetto per Q. suber le cui popolazioni rappresentano il margine orientale di distribuzione della specie, per questo più sottoposte ad impoverimento genetico. Oltre alla cluster analysis (UPGMA) e alla Analisi delle Componenti Principali effettuate per entrambi i marcatori, che confermano l’ipotesi dell’origine ibrida degli individui di Q. crenata diffusi in Italia Settentrionale, sono stati calcolati l’indice di ibridità basato sul maximum likelihood, che dimostra una introgressione asimmetrica di Q. crenata verso il parentale caratterizzato da superiorità demografica (Q. cerris) e il test di Mantel. Quest’ultimo ha permesso di confrontare i due marcatori RAPD e ISSR utilizzati ottenendo una bassa correlazione, a conferma del fatto che, amplificando tratti differenti del DNA nucleare, i dati non sono sovrapponibili, sebbene forniscano risultati analoghi. Per l’isolamento di loci microsatelliti ipervariabili ho utilizzato il protocolllo FIASCO (Fast isolation by AFLP of sequences containing repeats- Zane et al. 2002) che permette di costruire una libreria genomica arricchita partendo dal DNA estratto da P. apennina. Tale procedura ha previsto la digestione del DNA genomico per la produzione di una miscela di frammenti di DNA. Tramite ibridazione con opportune sonde sono stati isolati i frammenti contenenti i microsatelliti. Sequenziando i cloni ricombinanti, ho ottenuto sequenze contenenti repeats sulle cui regioni fiancheggianti sono stati costruiti 15 coppie di primer che potranno, in seguito, essere utilizzate per definire la quota di riproduzione clonale in P. apennina e per valutare la diversità genetica delle popolazioni che coprono l’areale di distribuzione della specie. Data la loro natura altamente variabile e la loro abbondanza nel DNA, gli SSR saranno, come i marcatori RAPD e gli ISSR, ugualmente validi per lo studio della variabilità genetica e per l’analisi di problematiche specifiche legate alle specie rare.

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By the end of the 19th century, geodesy has contributed greatly to the knowledge of regional tectonics and fault movement through its ability to measure, at sub-centimetre precision, the relative positions of points on the Earth’s surface. Nowadays the systematic analysis of geodetic measurements in active deformation regions represents therefore one of the most important tool in the study of crustal deformation over different temporal scales [e.g., Dixon, 1991]. This dissertation focuses on motion that can be observed geodetically with classical terrestrial position measurements, particularly triangulation and leveling observations. The work is divided into two sections: an overview of the principal methods for estimating longterm accumulation of elastic strain from terrestrial observations, and an overview of the principal methods for rigorously inverting surface coseismic deformation fields for source geometry with tests on synthetic deformation data sets and applications in two different tectonically active regions of the Italian peninsula. For the long-term accumulation of elastic strain analysis, triangulation data were available from a geodetic network across the Messina Straits area (southern Italy) for the period 1971 – 2004. From resulting angle changes, the shear strain rates as well as the orientation of the principal axes of the strain rate tensor were estimated. The computed average annual shear strain rates for the time period between 1971 and 2004 are γ˙1 = 113.89 ± 54.96 nanostrain/yr and γ˙2 = -23.38 ± 48.71 nanostrain/yr, with the orientation of the most extensional strain (θ) at N140.80° ± 19.55°E. These results suggests that the first-order strain field of the area is dominated by extension in the direction perpendicular to the trend of the Straits, sustaining the hypothesis that the Messina Straits could represents an area of active concentrated deformation. The orientation of θ agree well with GPS deformation estimates, calculated over shorter time interval, and is consistent with previous preliminary GPS estimates [D’Agostino and Selvaggi, 2004; Serpelloni et al., 2005] and is also similar to the direction of the 1908 (MW 7.1) earthquake slip vector [e.g., Boschi et al., 1989; Valensise and Pantosti, 1992; Pino et al., 2000; Amoruso et al., 2002]. Thus, the measured strain rate can be attributed to an active extension across the Messina Straits, corresponding to a relative extension rate ranges between < 1mm/yr and up to ~ 2 mm/yr, within the portion of the Straits covered by the triangulation network. These results are consistent with the hypothesis that the Messina Straits is an important active geological boundary between the Sicilian and the Calabrian domains and support previous preliminary GPS-based estimates of strain rates across the Straits, which show that the active deformation is distributed along a greater area. Finally, the preliminary dislocation modelling has shown that, although the current geodetic measurements do not resolve the geometry of the dislocation models, they solve well the rate of interseismic strain accumulation across the Messina Straits and give useful information about the locking the depth of the shear zone. Geodetic data, triangulation and leveling measurements of the 1976 Friuli (NE Italy) earthquake, were available for the inversion of coseismic source parameters. From observed angle and elevation changes, the source parameters of the seismic sequence were estimated in a join inversion using an algorithm called “simulated annealing”. The computed optimal uniform–slip elastic dislocation model consists of a 30° north-dipping shallow (depth 1.30 ± 0.75 km) fault plane with azimuth of 273° and accommodating reverse dextral slip of about 1.8 m. The hypocentral location and inferred fault plane of the main event are then consistent with the activation of Periadriatic overthrusts or other related thrust faults as the Gemona- Kobarid thrust. Then, the geodetic data set exclude the source solution of Aoudia et al. [2000], Peruzza et al. [2002] and Poli et al. [2002] that considers the Susans-Tricesimo thrust as the May 6 event. The best-fit source model is then more consistent with the solution of Pondrelli et al. [2001], which proposed the activation of other thrusts located more to the North of the Susans-Tricesimo thrust, probably on Periadriatic related thrust faults. The main characteristics of the leveling and triangulation data are then fit by the optimal single fault model, that is, these results are consistent with a first-order rupture process characterized by a progressive rupture of a single fault system. A single uniform-slip fault model seems to not reproduce some minor complexities of the observations, and some residual signals that are not modelled by the optimal single-fault plane solution, were observed. In fact, the single fault plane model does not reproduce some minor features of the leveling deformation field along the route 36 south of the main uplift peak, that is, a second fault seems to be necessary to reproduce these residual signals. By assuming movements along some mapped thrust located southward of the inferred optimal single-plane solution, the residual signal has been successfully modelled. In summary, the inversion results presented in this Thesis, are consistent with the activation of some Periadriatic related thrust for the main events of the sequence, and with a minor importance of the southward thrust systems of the middle Tagliamento plain.

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Crowding is defined as the negative effect obtained by adding visual distractors around a central target which has to be identified. Some studies have suggested the presence of a marked crowding effect in developmental dyslexia (e.g. Atkinson, 1991; Spinelli et al., 2002). Inspired by Spinelli’s (2002) experimental design, we explored the hypothesis that the crowding effect may affect dyslexics’ response times (RTs) and accuracy in identification tasks dealing with words, pseudowords, illegal non-words and symbolstrings. Moreover, our study aimed to clarify the relationship between the crowding phenomenon and the word-reading process, in an inter-language comparison perspective. For this purpose we studied twenty-two French dyslexics and twenty-two Italian dyslexics (total forty-four dyslexics), compared to forty-four subjects matched for reading level (22 French and 22 Italians) and forty-four chronological age-matched subjects (22 French and 22 Italians). Children were all tested on reading and cognitive abilities. Results showed no differences between French and Italian participants suggesting that performances were homogenous. Dyslexic children were all significantly impaired in words and pseudowords reading compared to their normal reading controls. Regarding the identification task with which we assessed crowding effect, both accuracy and RTs showed a lexicality effect which meant that the recognition of words was more accurate and faster in words than pseudowords, non-words and symbolstrings. Moreover, compared to normal readers, dyslexics’ RTs and accuracy were impaired only for verbal materials but not for non-verbal material; these results are in line with the phonological hypothesis (Griffiths & Snowling, 2002; Snowling, 2000; 2006) . RTs revealed a general crowding effect (RTs in the crowding condition were slower than those recorded in the isolated condition) affecting all the subjects’ performances. This effect, however, emerged to be not specific for dyslexics. Data didn’t reveal a significant effect of language, allowing the generalization of the obtained results. We also analyzed the performance of two subgroups of dyslexics, categorized according to their reading abilities. The two subgroups produced different results regarding the crowding effect and type of material, suggesting that it is meaningful to take into account also the heterogeneity of the dyslexia disorder. Finally, we also analyzed the relationship of the identification task with both reading and cognitive abilities. In conclusion, this study points out the importance of comparing visual tasks performances of dyslexic participants with those of their reading level-matched controls. This approach may improve our comprehension of the potential causal link between crowding and reading (Goswami, 2003).

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INTRODUCTION – In human medicine, diabetes mellitus (DM), hypertension, proteinuria and nephropathy are often associated although it is still not clear whether hypertension is the consequence or the cause of nephropathy and albuminuria. Microalbuminuria, in humans, is an early and sensitive marker which permits timely and effective therapy in the early phase of renal damage. Conversely, in dogs, these relationships were not fully investigated, even though hypertension has been associated with many diseases (Bodey and Michell, 1996). In a previous study, 20% of diabetic dogs were found proteinuric based on a U:P/C > 1 and 46% were hypertensive; this latter finding is similar to the prevalence of hypertension in diabetic people (40-80%) (Struble et al., 1998). In the same canine study, hypertension was also positively correlated with the duration of the disease, as is the case in human beings. Hypertension was also found to be a common complication of hypercortisolism (HC) in dogs, with a prevalence which varies from 50 (Goy-Thollot et al., 2002) to 80% (Danese and Aron, 1994).The aim of our study was to evaluate the urinary albumin to creatinine ratio (U:A/C) in dogs affected by Diabetes Mellitus and HC in order to ascertain if, as in human beings, it could represent an early and more sensitive marker of renal damage than U:P/C. Furthermore, the relationship between proteinuria and hypertension in DM and HC was also investigated. MATERIALS AND METHODS – Twenty dogs with DM, 14 with HC and 21 healthy dogs (control group) were included in the prospective case-control study. Inclusion criteria were hyperglycaemia, glicosuria and serum fructosamine above the reference range for DM dogs and a positive ACTH stimulation test and/or low-dose dexamethasone test and consistent findings of HC on abdominal ultrasonography in HC dogs. Dogs were excluded if affected by urinary tract infections and if the serum creatinine or urea values were above the reference range. At the moment of inclusion, an appropriate therapy had already been instituted less than 1 month earlier in 12 diabetic dogs. The control dogs were considered healthy based on clinical exam and clinicopathological findings. All dogs underwent urine sample collection by cystocentesis and systemic blood pressure measurement by means of either an oscillometric device (BP-88 Next, Colin Corporation, Japan) or by Doppler ultrasonic traducer (Minidop ES-100VX, Hadeco, Japan). The choice of method depended on the dog’s body weight: Doppler ultrasonography was employed in dogs < 20 kg of body weight and the oscillometric method in the other subjects. Dogs were considered hypertensive whenever systemic blood pressure was found ≥ 160 mmHg. The urine was assayed for U:P/C and U:A/C (Gentilini et al., 2005). The data between groups were compared using the Mann-Whitney U test. The reference ranges for U:P/C and U:A/C had already been established by our laboratory as 0.6 and 0.05, respectively. U:P/C and U:A/C findings were correlated to systemic blood pressure and Spearman R correlation coefficients were calculated. In all cases, p < 0.05 was considered statistically significant. RESULTS – The mean ± sd urinary albumin concentration in the three groups was 1.79 mg/dl ± 2.18; 20.02 mg/dl ± 43.25; 52.02 mg/dl ± 98.27, in healthy, diabetic and hypercortisolemic dogs, respectively. The urine albumin concentration differed significantly between healthy and diabetic dogs (p = 0.008) and between healthy and HC dogs (p = 0.011). U:A/C values ranged from 0.00 to 0.34 (mean ± sd 0.02 ± 0.07), 0.00 to 6.72 (mean ± sd 0.62 ± 1.52) and 0.00 to 5.52 (mean ± sd 1.27 ± 1.70) in the control, DM and HC groups, respectively; U:P/C values ranged from 0.1 to 0.6 (mean ± sd 0.17 ± 0.15) 0.1 to 6.6 (mean ± sd 0.93 ± 1.15) and 0.2 to 7.1 (mean ± sd 1.90 ± 2.11) in the control, DM and HC groups, respectively. In diabetic dogs, U:A/C was above the reference range in 11 out of 20 dogs (55%). Among these, 5/20 (25%) showed an increase only in the U:A/C ratio while, in 6/20 (30%), both the U:P/C and the U:A/C were abnormal. Among the latter, 4 dogs had already undergone therapy. In subjects affected with HC, U:P/C and U:A/C were both increased in 10/14 (71%) while in 2/14 (14%) only U:A/C was above the reference range. Overall, by comparing U:P/C and U:A/C in the various groups, a significant increase in protein excretion in disease-affected animals compared to healthy dogs was found. Blood pressure (BP) in diabetic subjects ranged from 88 to 203 mmHg (mean ± sd 143 ± 33 mmHg) and 7/20 (35%) dogs were found to be hypertensive. In HC dogs, BP ranged from 116 to 200 mmHg (mean ± sd 167 ± 26 mmHg) and 9/14 (64%) dogs were hypertensive. Blood pressure and proteinuria were not significantly correlated. Furthermore, in the DM group, U:P/C and U:A/C were both increased in 3 hypertensive dogs and 2 normotensive dogs while the only increase of U:A/C was observed in 2 hypertensive and 3 normotensive dogs. In the HC group, the U:P/C and the U:A/C were both increased in 6 hypertensive and 2 normotensive dogs; the U:A/C was the sole increased parameter in 1 hypertensive dog and in 1 dog with normal pressure. DISCUSSION AND CONCLUSION- The findings of this study suggest that, in dogs affected by DM and HC, an increase in U:P/C, U:A/C and systemic hypertension is frequently present. Remarkably, some dogs affected by both DM and HC showed an U:A/C but not U:P/C above the reference range. In diabetic dogs, albuminuria was observed in 25% of the subjects, suggesting the possibility that this parameter could be employed for detecting renal damage at an early phase when common semiquantiative tests and even U:P/C fall inside the reference range. In HC dogs, a higher number of subjects with overt proteinuria was found while only 14% presented an increase only in the U:A/C. This fact, associated with a greater number of hypertensive dogs having HC rather than DM, could suggest a greater influence on renal function by the mechanisms involved in hypertension secondary to hypercortisolemia. Furthermore, it is possible that, in HC dogs, the diagnosis was more delayed than in DM dogs. However, the lack of a statistically significant correlation between hypertension and increased protein excretion as well as the apparently random distribution of proteinuric subjects in normotensive and hypertensive cases, imply that other factors besides hypertension are involved in causing proteinuria. Longitudinal studies are needed to further investigate the relationship between hypertension and proteinuria.

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It is well known that the best grape quality can occur only through the achievement of optimal source/sink ratio. Vine balance is in fact a key parameter in controlling berry sugar, acidity and secondary metabolites content (Howell, 2001; Vanden Heuvel et al., 2004). Despite yield reduction and quality improvement are not always strictly related, cluster thinning is considered a technique which could lead to improvement in grape sugar and anthocyanin composition (Dokoozlian and Hirschfelt, 1995; Guidoni et al., 2002). Among several microclimatic variables which may impact grape composition, the effect of cluster light exposure and temperature, which probably act in synergistic and complex way, has been widely explored showing positive even sometimes contradictory results (Spayd et al., 2001; Tarara et al., 2008). Pre-bloom and véraison defoliation are very efficient techniques in inducing cluster microclimatic modification. Furthermore pre-bloom defoliation inducing a lower berry set percentage On these basis the aim of the first experiment of the thesis was to verify in cv Sangiovese the effects on ripening and berry composition of management techniques which may increase source/sink ratio and /or promote light incidence on berries throughout grape ripening. An integrated agronomic, biochemical and microarray approach, aims to understand which mechanisms are involved in berry composition and may be conditioned in the berries during ripening in vines submitted to three treatments. In particular the treatments compared were: a) cluster thinning (increasing in source/sink ratio) b) leaf removal at véraison (increasing cluster light exposure) c) pre-bloom defoliation (increasing source sink ratio and cluster light exposure). Vine response to leaf removal at véraison was further evaluated in the second experiment on three different varieties (Cabernet Sauvignon, Nero d’Avola, Raboso Piave) chosen for their different genetic traits in terms of anthocyanin amount and composition. The integrated agronomic, biochemical and microarray approach, employed in order to understand those mechanisms involved in berry composition of Sangiovese vines submitted to management techniques which may increase source/sink ratio and induce microclimatic changes, bring to interesting results. This research confirmed the main role of source/sink ratio in conditioning sugars metabolism and revealed also that carbohydrates availability is a crucial issue in triggering anthocyanin biosynthesis. More complex is the situation of pre-bloom defoliation, where source/sink and cluster light increase effects are associated to determine final berry composition. It results that the application of pre-bloom defoliation may be risky, as too much dependent on seasonal conditions (rain and temperature) and physiological vine response (leaf area recovery, photosynthetic compensation, laterals regrowth). Early induced stress conditions could bring cluster at véraison in disadvantage to trigger optimal berry ripening processes compared to untreated vines. This conditions could be maintained until harvest, if no previously described physiological recovery occurs. Certainly, light exposure increase linked to defoliation treatments, showed a positive and solid effect on flavonol biosynthesis, as in our conditions temperature was not so different among treatments. Except the last aspects, that could be confirmed also for véraison defoliation, microclimatic changes by themselves seemed not able to induce any modification in berry composition. Further studies are necessary to understand if the peculiar anthocyanic and flavonols composition detected in véraison defoliation could play important role in both color intensity and stability of wines.

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Several studies showed that sleep loss/fragmentation may have a negative impact on cognitive performance, mood and autonomic activity. Specific neurocognitive domains, such as executive function (i.e.,prefrontal cortex), seems to be particularly vulnerable to sleep loss. Pearson et al.(2006) evaluated 16 RLS patients compared to controls by cognitive tests, including those particularly sensitive to prefrontal cortical (PFC) functioning and sleep loss. RLS patients showed significant deficits on two of the three PFC tests. It has been recently reported that RLS is associated with psychiatric manifestations. A high prevalence of depressive symptoms has been found in patients with RLS(Rothdach AJ et al., 2000). RLS could cause depression through its adverse influences on sleep and energy. On the other hand, symptoms of depression such as sleep deprivation, poor nutrition or lack of exercise may predispose an individual to the development of RLS. Moreover, depressed patients may amplify mild RLS, making occasional RLS symptoms appear to meet threshold criteria. The specific treatment of depression could be also implicated, since antidepressant compounds may worsen RLS and PLMD(Picchietti D et al., 2005; Damsa C et al., 2004). Interestingly, treatments used to relieve RLS symptoms (dopamine agonists) seem to have an antidepressant effects in RLS depressed patients(Saletu M et al., 2002&2003). During normal sleep there is a well-regulated pattern of the autonomic function, modulated by changes in sleep stages. It has been reported that chronic sleep deprivation is associated with cardiovascular events. In patients with sleep fragmentation increased number of arousals and increased cyclic alternating pattern rate is associated with an increase in sympathetic activity. It has been demonstrated that PLMS occurrence is associated with a shift to increased sympathetic activity without significant changes in cardiac parasympathetic activity (Sforza E et al., 2005). An increased association of RLS with hypertension and heart disease has been documented in several studies(Ulfberg J et al., 2001; Ohayon MM et al., 2002).

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Questa tesi di dottorato è inserita nell’ambito della convenzione tra ARPA_SIMC (che è l’Ente finanziatore), l’Agenzia Regionale di Protezione Civile ed il Dipartimento di Scienze della Terra e Geologico - Ambientali dell’Ateneo di Bologna. L’obiettivo principale è la determinazione di possibili soglie pluviometriche di innesco per i fenomeni franosi in Emilia Romagna che possano essere utilizzate come strumento di supporto previsionale in sala operativa di Protezione Civile. In un contesto geologico così complesso, un approccio empirico tradizionale non è sufficiente per discriminare in modo univoco tra eventi meteo innescanti e non, ed in generale la distribuzione dei dati appare troppo dispersa per poter tracciare una soglia statisticamente significativa. È stato quindi deciso di applicare il rigoroso approccio statistico Bayesiano, innovativo poiché calcola la probabilità di frana dato un certo evento di pioggia (P(A|B)) , considerando non solo le precipitazioni innescanti frane (quindi la probabilità condizionata di avere un certo evento di precipitazione data l’occorrenza di frana, P(B|A)), ma anche le precipitazioni non innescanti (quindi la probabilità a priori di un evento di pioggia, P(A)). L’approccio Bayesiano è stato applicato all’intervallo temporale compreso tra il 1939 ed il 2009. Le isolinee di probabilità ottenute minimizzano i falsi allarmi e sono facilmente implementabili in un sistema di allertamento regionale, ma possono presentare limiti previsionali per fenomeni non rappresentati nel dataset storico o che avvengono in condizioni anomale. Ne sono esempio le frane superficiali con evoluzione in debris flows, estremamente rare negli ultimi 70 anni, ma con frequenza recentemente in aumento. Si è cercato di affrontare questo problema testando la variabilità previsionale di alcuni modelli fisicamente basati appositamente sviluppati a questo scopo, tra cui X – SLIP (Montrasio et al., 1998), SHALSTAB (SHALlow STABility model, Montgomery & Dietrich, 1994), Iverson (2000), TRIGRS 1.0 (Baum et al., 2002), TRIGRS 2.0 (Baum et al., 2008).