14 resultados para Thematic coding of visuals
em AMS Tesi di Dottorato - Alm@DL - Università di Bologna
Resumo:
Many psychophysical studies suggest that target depth and direction during reaches are processed independently, but the neurophysiological support to this view is so far limited. Here, we investigated the representation of reach depth and direction by single neurons in an area of the medial posterior parietal cortex (V6A). Single-unit activity was recorded from V6A in two Macaca fascicularis monkeys performing a fixation-to-reach task to targets at different depths and directions. We found that in a substantial percentage of V6A neurons depth and direction signals jointly influenced fixation, planning and arm movement-related activity in 3D space. While target depth and direction were equally encoded during fixation, depth tuning became stronger during arm movement planning, execution and target holding. The spatial tuning of fixation activity was often maintained across epochs, and this occurred more frequently in depth. These findings support for the first time the existence of a common neural substrate for the encoding of target depth and direction during reaching movements in the posterior parietal cortex. Present results also highlight the presence in V6A of several types of cells that process independently or jointly eye position and arm movement planning and execution signals in order to control reaches in 3D space. It is possible that depth and direction influence also the metrics of the reach action and that this effect on the reach kinematic variables can account for the spatial tuning we found in V6A neural activity. For this reason, we recorded and analyzed behavioral data when one monkey performed reaching movements in 3-D space. We evaluated how the target spatial position, in particular target depth and target direction, affected the kinematic parameters and trajectories describing the motor action properties.
Resumo:
The enteric nervous system regulates autonomously from the central nervous system all the reflex pathways that control blood flow, motility, water and electrolyte transport and acid secretion. The ability of the gut to function in isolation is one of the most intriguing phenomenons in neurogastroenterology. This requires coding of sensory stimuli by cells in the gut wall. Enteric neurons are prominent candidates to relay mechanosensitivity. Surprisingly, the identity of mechanosensitive neurons in the enteric nervous system as well as the appropriate stimulus modality is unknown despite the evidence that enteric neurons respond to sustained distension. Objectives: The aim of our study was to record from mechanosensitive neurons using physiological stimulus modalities. Identification of sensory neurons is of central importance to understand sensory transmission under normal conditions and in gut diseases associated with sensorimotor dysfunctions, such as Irritable Bowel Syndrome. Only then it will be possible to identify novel targets that help to normalise sensory functions. Methods: We used guinea-pig ileum myenteric plexus preparations and recorded responses of all neurons in a given ganglion with a fast neuroimaging technique based on voltage sensitive dyes. To evoke a mechanical response we used two different kinds of stimuli: firstly we applied a local mechanical distortion of the ganglion surface with von Frey hair. Secondarily we mimic the ganglia deformation during physiological movements of myenteric ganglia in a freely contracting ileal preparation. We were able to reliably and reproducibly mimic this distortion by intraganglionic injections of small volumes of oxygenated and buffered Krebs solution using stimulus parameters that correspond to single contractions. We also performed in every ganglion tested, electrical stimulations to evoke fast excitatory postsynaptic potentials. Immunohistochemistry reactions were done with antibodies against Calbindin and NeuN, considered markers for sensory neurons. Results: Recordings were performed in 46 ganglia from 31 guinea pigs. In every ganglion tested we found from 1 to 21 (from 3% to 62%) responding cells with a median value of 7 (24% of the total number of neurons). The response consisted of an almost instantaneous spike discharge that showed adaptation. The median value of the action potential frequency in the responding neurons was 2.0 Hz, with a recording time of 1255 ms. The spike discharge lasted for 302 ± 231 ms and occurred only during the initial deformation phase. During sustained deformation no spike discharge was observed. The response was reproducible and was a direct activation of the enteric neurons since it remained after synaptic blockade with hexamethonium or ω-conotoxin and after long time perfusion with capsaicin. Muscle tone appears not to be required for activation of mechanosensory neurons. Mechanosensory neurons showed a response to mechanical stimulation related to the stimulus strength. All mechanosensory neurons received fast synaptic inputs. There was no correlation between mechanosensitivity and Calbindin-IR and NeuN-IR (44% of mechanosensitive neurones Calb-IR-/NeuN-IR-). Conclusions: We identified mechanosensitive neurons in the myenteric plexus of the guinea pig ileum which responded to brief deformation. These cells appear to be rapidly accommodating neurons which respond to dynamic change. All mechanosensitive neurons received fast synaptic input suggesting that their activity can be highly modulated by other neurons and hence there is a low stimulus fidelity which allows adjusting the gain in a sensory network. Mechanosensitivity appears to be a common feature of many enteric neurons belonging to different functional classes. This supports the existence of multifunctional enteric neurons which may fulfil sensory, integrative and motor functions.
Resumo:
The posterior parietal cortex (PPC) of primates represents a remarkable platform that has evolved over time to solve some of the computational challenges that we face in the everyday life, such as sensorimotor integration, spatial attention, and motor planning. With the aim of further investigating the multifaceted functional characteristics of medial PPC, we conducted three studies to explore the visuomotor, somatic, visual, and attention-related properties of two PPC areas: V6A, a visuomotor area part of the dorsomedial visual stream, and PE, an area strongly dominated by somatomotor input, residing mainly on the exposed surface of the superior parietal lobule. In the first study, we tested the impact of visual feedback on V6A grasp-related activity during arm movements towards objects of different shapes. Our results demonstrate that V6A is modulated by both grip type and visual information during grasping preparation and execution, with a predominance of cells influenced by grip type. In the second study, we explored the influence of depth and direction information on reach-related activity of neurons in the so far largely neglected medial part of area PE. We observed a remarkable trend in medial PPC, going from the joint coding of depth and direction signals caudally, in area V6A, to a largely segregated processing of the two signals rostrally, in area PE. In the third study, we used a combined fMRI-electrophysiology experiment to investigate the neuronal mechanisms underlying covert shift of attention processes in area V6A. Our preliminary results reveal that half of the cells showed shift-selective activity when the monkey covertly shifted its attention towards the receptive field. All together these findings highlight the role of the medial PPC in integrating information coming from different sources (vision, somatosensory and motor) and emphasize the involvement of action-related regions of the dorsomedial visual stream in higher level cognitive functions.
Resumo:
Premise: In the literary works of our anthropological and cultural imagination, the various languages and the different discursive practices are not necessarily quoted, expressly alluded to or declared through clear expressive mechanisms; instead, they rather constitute a substratum, a background, now consolidated, which with irony and intertextuality shines through the thematic and formal elements of each text. The various contaminations, hybridizations and promptings that we find in the expressive forms, the rhetorical procedures and the linguistic and thematic choices of post-modern literary texts are shaped as fluid and familiar categories. Exchanges and passages are no longer only allowed but also inevitable; the post-modern imagination is made up of an agglomeration of discourses that are no longer really separable, built up from texts that blend and quote one another, composing, each with its own specificities, the great family of the cultural products of our social scenario. A literary work, therefore, is not only a whole phenomenon, delimited hic et nunc by a beginning and an ending, but is a fragment of that complex, dense and boundless network that is given by the continual interrelations between human forms of communication and symbolization. The research hypothesis: A vision is delineated of comparative literature as a discipline attentive to the social contexts in which texts take shape and move and to the media-type consistency that literary phenomena inevitably take on. Hence literature is seen as an open systematicity that chooses to be contaminated by other languages and other discursive practices of an imagination that is more than ever polymorphic and irregular. Inside this interpretative framework the aim is to focus the analysis on the relationship that postmodern literature establishes with advertising discourse. On one side post-modern literature is inserted in the world of communication, loudly asserting the blending and reciprocal contamination of literary modes with media ones, absorbing their languages and signification practices, translating them now into thematic nuclei, motifs and sub-motifs and now into formal expedients and new narrative choices; on the other side advertising is chosen as a signification practice of the media universe, which since the 1960s has actively contributed to shaping the dynamics of our socio-cultural scenarios, in terms which are just as important as those of other discursive practices. Advertising has always been a form of communication and symbolization that draws on the collective imagination – myths, actors and values – turning them into specific narrative programs for its own texts. Hence the aim is to interpret and analyze this relationship both from a strictly thematic perspective – and therefore trying to understand what literature speaks about when it speaks about advertising, and seeking advertising quotations in post-modern fiction – and from a formal perspective, with a search for parallels and discordances between the rhetorical procedures, the languages and the verifiable stylistic choices in the texts of the two different signification practices. The analysis method chosen, for the purpose of constructive multiplication of the perspectives, aims to approach the analytical processes of semiotics, applying, when possible, the instruments of the latter, in order to highlight the thematic and formal relationships between literature and advertising. The corpus: The corpus of the literary texts is made up of various novels and, although attention is focused on the post-modern period, there will also be ineludible quotations from essential authors that with their works prompted various reflections: H. De Balzac, Zola, Fitzgerald, Joyce, Calvino, etc… However, the analysis focuses the corpus on three authors: Don DeLillo, Martin Amis and Aldo Nove, and in particular the followings novels: “Americana” (1971) and “Underworld” (1999) by Don DeLillo, “Money” (1984) by Martin Amis and “Woobinda and other stories without a happy ending” (1996) and “Superwoobinda” (1998) by Aldo Nove. The corpus selection is restricted to these novels for two fundamental reasons: 1. assuming parameters of spatio-temporal evaluation, the texts are representative of different socio-cultural contexts and collective imaginations (from the masterly glimpses of American life by DeLillo, to the examples of contemporary Italian life by Nove, down to the English imagination of Amis) and of different historical moments (the 1970s of DeLillo’s Americana, the 1980s of Amis, down to the 1990s of Nove, decades often used as criteria of division of postmodernism into phases); 2. adopting a perspective of strictly thematic analysis, as mentioned in the research hypothesis, the variations and the constants in the novels (thematic nuclei, topoi, images and narrative developments) frequently speak of advertising and inside the narrative plot they affirm various expressions and realizations of it: value ones, thematic ones, textual ones, urban ones, etc… In these novels the themes and the processes of signification of advertising discourse pervade time, space and the relationships that the narrator character builds around him. We are looking at “particle-characters” whose endless facets attest the influence and contamination of advertising in a large part of the narrative developments of the plot: on everyday life, on the processes of acquisition and encoding of the reality, on ideological and cultural baggage, on the relationships and interchanges with the other characters, etc… Often the characters are victims of the implacable consequentiality of the advertising mechanism, since the latter gets the upper hand over the usual processes of communication, which are overwhelmed by it, wittingly or unwittingly (for example: disturbing openings in which the protagonist kills his or her parents on the basis of a spot, former advertisers that live life codifying it through the commercial mechanisms of products, sons and daughters of advertisers that as children instead of playing outside for whole nights saw tapes of spots.) Hence the analysis arises from the text and aims to show how much the developments and the narrative plots of the novels encode, elaborate and recount the myths, the values and the narrative programs of advertising discourse, transforming them into novel components in their own right. And also starting from the text a socio-cultural reference context is delineated, a collective imagination that is different, now geographically, now historically, and from comparison between them the aim is to deduce the constants, the similarities and the variations in the relationship between literature and advertising.
Resumo:
L’oggetto dell’analisi si situa all’intersezione di diversi ambiti disciplinari: letteratura, scienze dell’educazione, sociologia, psicologia. Nel presente lavoro, viene privilegiata un’analisi tematica della narrativa e la definizione identitaria delle “infanzie migranti” viene declinata seguendo percorsi di lettura che mettano in risalto alcune prospettive ricorrenti nei romanzi. Il corpus letterario selezionato include alcuni romanzi scritti in lingua inglese da sei scrittrici di origine indiana, in particolare Jamila Gavin, Rachna Gilmore, Anjali Banerjee, Rukhsana Khan, Ravinder Randhawa e Meera Syal. Nel primo capitolo si tracciano le premesse teoriche e metodologiche del lavoro, definendo il genere della letteratura per l’infanzia e interrogandoci sulle sue specificità in un contesto postcoloniale qual è quello indiano. Il secondo capitolo è dedicato alla definizione identitaria delle seconde generazioni, in particolar modo di quelle indo-britanniche e indo-canadesi, cui appartengono i protagonisti dei romanzi presi in esame. Nel terzo capitolo viene posta attenzione agli elementi che concorrono alla definizione identitaria dei giovani protagonisti dei romanzi, i quali si interrogano sul loro essere e sull’appartenenza interculturale. I dialoghi intergenerazionali tra i protagonisti e i nonni - o altre figure di guida - permettono alle scrittrici di raccontare la storia dell’India coloniale e della lotta per l’indipendenza dal punto di vista degli esclusi dalla storiografia ufficiale. Nel capitolo conclusivo si argomenta invece come la definizione identitaria si attui per mezzo dello spazio, tramite l’appartenenza ai luoghi, spazi caricati di significato, e per mezzo del viaggio, che può essere reale, immaginario o iniziatico. In tutti i casi, il viaggio porta alla scoperta del Sé, di un’identità ibrida e molteplice da parte dei personaggi.
Resumo:
Il fulcro tematico e concettuale della tesi consiste nel rapporto complesso, paradossale e spesso anche controverso esistente fra il teatro e la performance (art) – e cioè il rapporto fra i concetti di “teatralità” e di “performatività”. L’attenzione è posta su quelle correnti nelle arti performative contemporanee che tendono allo scioglimento delle nozioni di genere, disciplina, tecnica e autorialità e che mettono in questione lo status stesso dell’opera performativa (lo spettacolo) in quanto prodotto esclusivamente estetico, cioè spettacolare. Vengono esaminate – prelevando rispettivamente dal campo del teatro, della danza e della performance art – le pratiche di Jerzy Grotowski e Thomas Richards, Jérôme Bel e Marina Abramović. Quello che accomuna queste pratiche ben diverse tra loro non è soltanto la problematica del rapporto fra teatralità e performatività ma soprattutto l’aspetto particolarmente radicale e assiduo (e anche paradossale) del loro doppio sforzo, che consiste nello spingere la propria disciplina oltre ogni confine prestabilito e nello stesso tempo nel cercare di ri-definire i suoi codici fondanti e lo statuto ontologico che la distinguerebbero dalle altre discipline performative. Sono esaminate anche diverse teorizzazioni della performance con particolare attenzione a quei contributi che mettono in luce (e in questione) il delicato rapporto fra il teatro e la performance (art) attraverso una (ri)concettualizzazione e comparazione dei termini di teatralità e di performatività. La tesi esamina l’evoluzione della comprensione di quel rapporto all’interno del campo teorico-storico e artistico che inizialmente riflette la tendenza a percepire il rapporto in termini di opposizione e addirittura esclusione per approdare col tempo a una visione più riconciliante e complementare. Le radicali pratiche contemporanee fra il teatro e la performance rappresentano forse una nuova forma-processo performativa specifica e autonoma – che potrebbe essere definita tout court “performance” – e con cui viene definitivamente superato il progetto teatrale modernista?
Resumo:
Ce travail est une analyse de la représentation du pathétique masculin dans le roman dit sentimental dans la deuxième moitié du dix-huitième siècle en Europe, ou plutôt dans les littératures anglaise, française, allemande et italienne. La thèse soutenue est celle de la dérivation du pathétique romanesque de l’âge des Lumières des pratiques de prédication religieuse du siècle précédent et donc de la valeur normative du roman sentimental à ses débuts : celui-ci aurait relayé le rôle des manuels de conduite des siècles précédents et se serait posé comme un répertoire d’exempla comportementaux adaptés aux différentes situations de la vie. Nous avons suivi les évolutions historiques du genre à travers l’analyse thématique du motif des larmes masculines. Pour ce faire, nous avons examiné la complexe proxémique de représentation de l’émotion et la diégèse qui en résulte, qui peut être nuancée, selon une terminologie récente, en pathétique attendrissant, sentimental et spectaculaire. Cela a entraîne la prise en compte de diverses formes artistiques, de la peinture au théâtre. La méthodologie utilisé conjugue l’histoire des idées et l’étude des formes de l’imaginaire, le pathétique appartenant au domaine de la philosophie autant qu’à celui de la représentation artistique : le concept glisse au dix-huitième siècle du champ rhétorique et stylistique à une dimension esthétique et anthropologique. Le travail a donc été divisé en trois grandes parties qui analysent les trois dimensions anthropologiques fondamentales : l’imaginaire religieux et l’héritage des anciens, c’est–à-dire le rapport que l’époque établit avec la tradition culturelle qui la précède ; l’imaginaire amoureux, qui se concentre sur les rapports entre les deux sexes et sur la « féminisation » du héros romanesque sentimental ; l’imaginaire familial, qui aborde les conséquences de ce changement dans la représentation de la masculinité au sein de la représentation de la famille et des rapports intergénérationnels.
Resumo:
INTRODUZIONE - La presente ricerca è incentrata sul monitoraggio dell’efficacia dei progetti di Educazione Avventura con adolescenti difficili, in particolare del progetto “Lunghi cammini educativi”. A partire da un’analisi della letteratura sull’educazione esperienziale nature-based e in particolare sull’Adventure Education con adolescenti difficili, è stata progettata una rilevazione empirica attraverso cui sperimentare un metodo di monitoraggio finalizzato a cogliere la dimensione processuale (che nella ricerca nell’ambito resta spesso inesplorata, poiché sono maggiormente diffusi i metodi di monitoraggio cosiddetti “black-box”), utilizzando un sistema integrato di diverse tecniche di rilevazione. Le due principali domande che hanno guidato la ricerca sono state: 1.Quali processi educativi significativi si innescano e possono essere osservati durante l’esperienza? 2.Il metodo dell’intervista camminata, integrato ad altri metodi, è utile per individuare e monitorare questi processi? METODO - Collocandosi all’interno di un framework metodologico qualitativo (influenzato da riflessioni post-qualitative, paradigma delle mobilità e sguardo fenomenologico), la ricerca prende la forma di uno studio di caso singolo con due unità di analisi, e prevede la triangolazione di diversi metodi di raccolta dei dati: analisi documentale; osservazione partecipante nei cammini e nelle riunioni di équipe; interviste (prima, durante, dopo il cammino) con differenti tecniche: camminata, “image-elicited”, tradizionale, online. RISULTATI - L’analisi tematica abduttiva delle interviste e delle osservazioni conferma quanto già evidenziato dalla letteratura circa la centralità della dilatazione del campo d’esperienza e del lavoro su alcune life skills (in particolare, competenze personali e growth mindset). Emergono anche alcuni key findings inattesi: il notevole “peso” dello stile educativo dell’accompagnatore; la “scoperta” del ruolo della quotidianità all’interno dell’esperienza straordinaria; la necessità di consapevolezza riguardo al potenziale educativo dell’ambiente (naturale e/o antropizzato), per una maggiore intenzionalità nelle scelte strategiche di cammino. L’intervista camminata, nonostante alcuni limiti, si conferma come metodo effettivamente utile a cogliere la dimensione processuale, e coerente con il contesto indagato.
Resumo:
Il progetto del dottorato di ricerca ha permesso di estendere il lavoro svolto sul Sistema Informativo 3D del Cantiere della Fontana del Nettuno al fine di definire la struttura concettuale e i relativi contenuti tematici di una piattaforma open source in grado di sviluppare la documentazione di restauro, sia per opere complesse caratterizzate dalla presenza di molti materiali costitutivi, sia per interventi più semplici nel quale preservare memoria e fornire libero accesso ai dati. Il confronto tra il SI del Cantiere della Fontana del Nettuno con le attuali metodologie utilizzate in campo nazionale ed internazionale ha permesso di ampliare i lessici necessari per la documentazione grafica e testuale da effettuare su diverse classi di materiali, creando delle cartelle integrate da combinare in base ai materiali costitutivi delle opere da restaurare. Il lavoro ha permesso la redazione di un lessico specifico per i diversi materiali costitutivi fornendo una banca dati informatizzata di facile consultazione.
Resumo:
This study aims to explore the Italian students’ perspectives on using English in English-medium instruction (EMI) programs in light of the practices of internationalization at home (IaH) at the University of Bologna (UNIBO) in Italy and further investigates whether these attitudes affect their language identity as English as lingua franca (ELF) users. To serve this aim, a mixed-method approach was adopted to collect quantitative and in-depth qualitative data in two phases through an online survey and a semi-structured interview. A total number of 78 Italian students participated in the survey, out of which 14 participants were interviewed. The findings of the online survey indicated that most participants (92%) held a positive perspective toward the use of English in EMI programs and the findings from the interviews were in line with the results of the survey. However, the purpose of the interviews was to explore the participants’ views on their language identity as ELF users. Thematic analysis of the interviews revealed that students experience emotional, cognitive, and social transitions in EMI programs in response to their shift from a non-EMI to an EMI academic setting. Overall, all the above-mentioned transitions were positive and could lead to personal development. However, it can be concluded that the EMI context provides few opportunities for the emergence of significant new subject positions mediated by English in this study. The focus on students’ perspectives on the use of English in EMI programs can contribute to the improvement in language policy planning and internationalized curriculum design by policymakers and alleviate tensions over the controversial issue of the Englishization of higher education by considering how EMI students perceive their use of English as ELF users not superior standard English users.
Resumo:
Die Arbeit schlägt eine systematische Studie der Rezeption des antiken Rom in den Werken von Heiner Müller vor. Die Analyse von Dramen, Gedichten und Essays, sowie von Interviews und Manuskripten, liefert ein umfassendes Bild wiederholter und vielschichtiger Begegnungen mit der römischen Geschichte und Literatur, die bisher weitgehend im kritischen Diskurs im Schatten standen. Der Schwerpunkt der Analyse liegt einerseits auf dem philologisch-literarischen Vergleich mit diesen Quellen und andererseits auf der darauf basierenden Rekonstruktion des umfassenden Bildes eines Imperiums, das seine historischen Grenzen überschreitet, um zu einem zivilisatorischen Prinzip zu werden, so allgegenwärtig wie ambivalent – das "Urbild" einer unauflöslichen Verschränkung von Staat und Gewalt, Kultur und Barbarei, Gesetz und Terror. Diese kulturelle Prägung zeigt sich nicht nur in Werken mit römischem Thema, sondern auch in nachfolgenden historischen Konstellationen, die Müller inszenierte, vom Elisabethanischen England über das Preußen Friedrichs II. bis hin zu den Blöcken des 20. Jahrhunderts. Besondere Aufmerksamkeit wird der Untersuchung literarischer Einflüsse und philosophischer Vorgänger dieser zivilisationskritischen Vision Roms gewidmet – eine Untersuchung, die bestehende Interpretationen korrigiert und neue einführt. Im Lichte des thematischen Komplexes "Rom" wird so ein beträchtlicher Teil von Müllers Produktion neu interpretiert, wodurch ein neues hermeneutisches Paradigma ebenso wie bisher übersehene Einflüsse und intertextuelle Beziehungen bei der Untersuchung von Dramen und Lyrik hervortreten.
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The transcribed ultraconserved regions (T-UCRs) are a group of long non-coding RNAs involved in human carcinogenesis. The factors regulating the expression of T-UCRs and their mechanism of action in human cancers are unknown. In this work it was shown that high expression of uc.339 associates with lower survival in 204 non-small cell lung cancer (NSCLC) patients. Moreover, it was shown that uc.339 found up-regulated in archival NSCLC samples, acts as a decoy RNA for miR-339-3p, -663-3p and -95-5p. So, Cyclin E2, a direct target of three microRNAs is up-regulated, inducing cancer growth and migration. Evidence of this mechanism was provided from cell lines and primary samples confirming that TP53 directly regulates uc.339. These results support a key role for uc.339 in lung cancer.
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Cutaneous melanoma (CM) is a potentially lethal form of skin cancer and its most important histopathologic factor for staging is Breslow thickness (BT). Its correct determination is fundamental for pathologists. A deeper understanding of the molecular processes guiding CM pathogenesis could improve diagnosis, treatment and prognosis. MicroRNAs (miRNAs) play a key role in CM biology. The firs aim was to investigate miRNA expression in reference to BT assessment. We found that the combined miRNA expression of miR-21-5p and miR-146a-5p above or below 1.5 was significantly associated with overall survival and successfully identified all superficially spreading melanoma (SSM) patients with relapsing suggesting that the combined assessment of these miRNAs expression could aid in SSM staging. Secondly, we focus on multiple primary melanoma (MPM) patients, which develop multiple primary melanomas in their lifetime, and represent a model of high-risk CM occurrence. We explored the miRNome of single CM and MPM: CM and MPM present several dysregulated miRNAs, including key miRNAs involved in epithelial-mesenchymal transition. A different miRNA profile was observed between 1st and 2nd melanoma from the same patient. MiRNA target analysis revealed a more differentiated and less invasive status of MPMs compared to CMs. This characterization of the miRNA regulatory network of MPMs highlights molecular features differentiating this subtype from CM. Recently, NGS experiments revealed the existence of miRNA variants (isomiRs) with different length and sequence. We identified a shorter 3’isoform as tenfold over-represented compared to the canonical form of miR-125a-5p. Target analysis revealed that miRNA shortening could change the pattern of target gene regulation. Finally, we study miRNA and isomiR dysregulation in benign nevi (BN) and CM and in CM and melanoma metastasis. The reported non-random dysregulation of specific isomiRs contributes to the understanding of the complex melanoma pathogenesis and serves as the basis for further functional studies.
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The importance of Helicobacter pylori as a human pathogen is underlined by the plethora of diseases it is responsible for. The capacity of H. pylori to adapt to the restricted host-associated environment andto evade the host immune response largely depends on a streamlined signalling network. The peculiar H. pylori small genome size combined with its paucity of transcriptional regulators highlights the relevance of post-transcriptional regulatory mechanisms as small non-coding RNAs (sRNAs). However, among the 8 RNases represented in H. pylori genome, a regulator guiding sRNAs metabolism is still not well studied. We investigated for the first time the physiological role in H. pylori G27 strain of the RNase Y enzyme. In the first line of research we provide a comprehensive characterization of the RNase Y activity by analysing its genomic organization and the factors that orchestrate its expression. Then, based on bioinformatic prediction models, we depict the most relevant determinants of RNase Y function, demonstrating a correlation of both structure and domain organization with orthologues represented in Gram-positive bacteria. To unveil the post-transcriptional regulatory effect exerted by the RNase Y, we compared the transcriptome of an RNase Y knock-out mutant to the parental wild type strain by RNA-seq approach. In the second line of research we characterized the activity of this single strand specific endoribonuclease on cag-PAI non coding RNA 1 (CncR1) sRNA. We found that deletion or inactivation of RNase Y led to the accumulation of a 3’-extended CncR1 (CncR1-L) transcript over time. Moreover, beneath its increased half-life, CncR1-L resembled a CncR1 inactive phenotype. Finally, we focused on the characterization of the in vivo interactome of CncR1. We set up a preliminary MS2-affinity purification coupled with RNA-sequencing (MAPS) approach and we evaluated the enrichment of specific targets, demonstrating the suitability of the technique in the H. pylori G27 strain.