Sistema nervoso enterico e scrapie sperimentale in ovini di razza sarda con diversa suscettibilità genetica nei confronti della malattia

Sebbene il sistema nervoso enterico (“enteric nervous system”, ENS) svolga un ruolo cruciale nella patogenesi della Scrapie ovina, non esistono tuttavia in letteratura dati sulle popolazioni cellulari progressivamente coinvolte nel corso dell’infezione, né sugli eventuali danni morfo-funzionali da esse subiti. Il presente studio è stato condotto sui plessi mienterici e sottomucosi dell’ileo di 46 pecore di razza Sarda, recanti diversi polimorfismi del gene Prnp (ARQ/ARQ, ARQ/AHQ, ARQ/ARR, ARR/ARR). I suddetti animali, infettati per os all’età di 8 mesi con un ceppo di Scrapie precedentemente caratterizzato nel topo, sono stati sacrificati mediante eutanasia a determinati intervalli di tempo post-infezione (p.i.). E’ stata quindi valutata, tramite immunoistochimica ed immunofluorescenza indiretta su sezioni tissutali e su preparati “wholemount”, l’immunoreattività (IR) nei confronti della PrPSc, del “marker” panneuronale Hu C/D, dell’ossido-nitrico sintetasi (nNOS), della calbindina (CALB) e della proteina fibrillare acida gliale (GFAP). In 8 pecore con genotipo ARQ/ARQ, clinicamente sane e sacrificate a 12-24 mesi p.i., nonché in 5 ovini clinicamente affetti (2 con genotipo ARQ/ARQ, 3 con genotipo ARQ/AHQ), questi ultimi sacrificati rispettivamente a 24, 36 e 40 mesi p.i., le indagini immunoistochimiche hanno consentito di dimostrare la presenza di PrPSc a livello sia dell’encefalo (obex), sia dell’ENS, in particolar modo nei plessi mienterici. In tali distretti il deposito della PrPSc risultava pienamente compatibile con un interessamento delle cellule enterogliali (“enteroglial cells”, EGCs), mentre occasionalmente si notava un contestuale coinvolgimento della componente neuronale ivi residente. In conclusione, i dati della presente indagine consentono di ipotizzare un verosimile coinvolgimento delle EGCs e dei neuroni residenti a livello dei plessi dell’ENS nella patogenesi della Scrapie sperimentale realizzata per os in ovini di razza Sarda.

Studio di fenomeni d'instabilità gravitativa sui fondali marini, con particolare riferimento all'isola di Stromboli

In the last decade the interest for submarine instability grew up, driven by the increasing exploitation of natural resources (primary hydrocarbons), the emplacement of bottom-lying structures (cables and pipelines) and by the development of coastal areas, whose infrastructures increasingly protrude to the sea. The great interest for this topic promoted a number of international projects such as: STEAM (Sediment Transport on European Atlantic Margins, 93-96), ENAM II (European North Atlantic Margin, 96-99), GITEC (Genesis and Impact of Tsunamis on the European Coast 92-95), STRATAFORM (STRATA FORmation on Margins, 95-01), Seabed Slope Process in Deep Water Continental Margin (Northwest Gulf of Mexico, 96-04), COSTA (Continental slope Stability, 00-05), EUROMARGINS (Slope Stability on Europe’s Passive Continental Margin), SPACOMA (04-07), EUROSTRATAFORM (European Margin Strata Formation), NGI's internal project SIP-8 (Offshore Geohazards), IGCP-511: Submarine Mass Movements and Their Consequences (05-09) and projects indirectly related to instability processes, such as TRANSFER (Tsunami Risk ANd Strategies For the European region, 06-09) or NEAREST (integrated observations from NEAR shore sourcES of Tsunamis: towards an early warning system, 06-09). In Italy, apart from a national project realized within the activities of the National Group of Volcanology during the framework 2000-2003 “Conoscenza delle parti sommerse dei vulcani italiani e valutazione del potenziale rischio vulcanico”, the study of submarine mass-movement has been underestimated until the occurrence of the landslide-tsunami events that affected Stromboli on December 30, 2002. This event made the Italian Institutions and the scientific community more aware of the hazard related to submarine landslides, mainly in light of the growing anthropization of coastal sectors, that increases the vulnerability of these areas to the consequences of such processes. In this regard, two important national projects have been recently funded in order to study coastal instabilities (PRIN 24, 06-08) and to map the main submarine hazard features on continental shelves and upper slopes around the most part of Italian coast (MaGIC Project). The study realized in this Thesis is addressed to the understanding of these processes, with particular reference to Stromboli submerged flanks. These latter represent a natural laboratory in this regard, as several kind of instability phenomena are present on the submerged flanks, affecting about 90% of the entire submerged areal and often (strongly) influencing the morphological evolution of subaerial slopes, as witnessed by the event occurred on 30 December 2002. Furthermore, each phenomenon is characterized by different pre-failure, failure and post-failure mechanisms, ranging from rock-falls, to turbidity currents up to catastrophic sector collapses. The Thesis is divided into three introductive chapters, regarding a brief review of submarine instability phenomena and related hazard (cap. 1), a “bird’s-eye” view on methodologies and available dataset (cap. 2) and a short introduction on the evolution and the morpho-structural setting of the Stromboli edifice (cap. 3). This latter seems to play a major role in the development of largescale sector collapses at Stromboli, as they occurred perpendicular to the orientation of the main volcanic rift axis (oriented in NE-SW direction). The characterization of these events and their relationships with successive erosive-depositional processes represents the main focus of cap.4 (Offshore evidence of large-scale lateral collapses on the eastern flank of Stromboli, Italy, due to structurally-controlled, bilateral flank instability) and cap. 5 (Lateral collapses and active sedimentary processes on the North-western flank of Stromboli Volcano), represented by articles accepted for publication on international papers (Marine Geology). Moreover, these studies highlight the hazard related to these catastrophic events; several calamities (with more than 40000 casualties only in the last two century) have been, in fact, the direct or indirect result of landslides affecting volcanic flanks, as observed at Oshima-Oshima (1741) and Unzen Volcano (1792) in Japan (Satake&Kato, 2001; Brantley&Scott, 1993), Krakatau (1883) in Indonesia (Self&Rampino, 1981), Ritter Island (1888), Sissano in Papua New Guinea (Ward& Day, 2003; Johnson, 1987; Tappin et al., 2001) and Mt St. Augustine (1883) in Alaska (Beget& Kienle, 1992). Flank landslide are also recognized as the most important and efficient mass-wasting process on volcanoes, contributing to the development of the edifices by widening their base and to the growth of a volcaniclastic apron at the foot of a volcano; a number of small and medium-scale erosive processes are also responsible for the carving of Stromboli submarine flanks and the transport of debris towards the deeper areas. The characterization of features associated to these processes is the main focus of cap. 6; it is also important to highlight that some small-scale events are able to create damage to coastal areas, as also witnessed by recent events of Gioia Tauro 1978, Nizza, 1979 and Stromboli 2002. The hazard potential related to these phenomena is, in fact, very high, as they commonly occur at higher frequency with respect to large-scale collapses, therefore being more significant in terms of human timescales. In the last chapter (cap. 7), a brief review and discussion of instability processes identified on Stromboli submerged flanks is presented; they are also compared with respect to analogous processes recognized in other submerged areas in order to shed lights on the main factors involved in their development. Finally, some applications of multibeam data to assess the hazard related to these phenomena are also discussed.

Morphological and physiological responses of apple trees under photoselective colored nets

In recent years and thanks to innovative technological advances in supplemental lighting sources and photo-selective filters, light quality manipulation (i.e. spectral composition of sunlight) have demonstrated positive effects on plant performance in ornamentals and vegetable crops. However, this aspect has been much less studied in fruit trees due to the difficulty of conditioning the light environment of orchards. The aim of the present PhD research was to study the use of different colored nets with selective light transmission in the blue (400 – 500 nm), red (600 – 700 nm) and near infrared (700 – 1100 nm) wavelengths as a tool to the light quality management and its morphological and physiological effects in field-grown apple trees. Chapter I provides a review the current status on physiological and technological advances on light quality management in fruit trees. Chapter II shows the main effect of colored nets on morpho-anatomical (stomata density, mesophyll structure and leaf mass area index) characteristics in apple leaves. Chapter III provides an analysis about the effect of micro-environmental conditions under colored nets on leaf stomatal conductance and leaf photosynthetic capacity. Chapter IV describes a study approach to evaluate the impact of colored nets on fruit growth potential in apples. Summing up results obtained in the present PhD dissertation clearly demonstrate that light quality management through photo-selective colored nets presents an interesting potential for the manipulation of plant morphological and physiological traits in apple trees. Cover orchards with colored nets might be and alternative technology to address many of the most important challenges of modern fruit growing, such as: the need for the efficient use of natural resources (water, soil and nutrients) the reduction of environmental impacts and the mitigation of possible negative effects of global climate change.

Magma injections and destabilization of basaltic volcanoes: a numerical study. Application to La Reunion (Indian ocean, France) and Stromboli (Tyrrhenian sea, Italy)

Most basaltic volcanoes are affected by recurrent lateral instabilities during their evolution. Numerous factors have been shown to be involved in the process of flank destabilization occurring over long periods of time or by instantaneous failures. However, the role of these factors on the mechanical behaviour and stability of volcanic edifices is poorly-constrained as lateral failure usually results from the combined effects of several parameters. Our study focuses on the morphological and structural comparison of two end-member basaltic systems, La Reunion (Indian ocean, France) and Stromboli (southern Tyrrhenian sea, Italy). We showed that despite major differences on their volumes and geodynamic settings, both systems present some similarities as they are characterized by an intense intrusive activity along well-developed rift zones and recurrent phenomena of flank collapse during their evolution. Among the factors of instability, the examples of la Reunion and Stromboli evidence the major contribution of intrusive complexes to volcano growth and destruction as attested by field observations and the monitoring of these active volcanoes. Classical models consider the relationship between vertical intrusions of magma and flank movements along a preexisting sliding surface. A set of published and new field data from Piton des Neiges volcano (La Reunion) allowed us to recognize the role of subhorizontal intrusions in the process of flank instability and to characterize the geometry of both subvertical and subhorizontal intrusions within basaltic edifices. This study compares the results of numerical modelling of the displacements associated with high-angle and low-angle intrusions within basaltic volcanoes. We use a Mixed Boundary Element Method to investigate the mechanical response of an edifice to the injection of magmatic intrusions in different stress fields. Our results indicate that the anisotropy of the stress field favours the slip along the intrusions due to cointrusive shear stress, generating flank-scale displacements of the edifice, especially in the case of subhorizontal intrusions, capable of triggering large-scale flank collapses on basaltic volcanoes. Applications of our theoretical results to real cases of flank displacements on basaltic volcanoes (such as the 2007 eruptive crisis at La Reunion and Stromboli) revealed that the previous model of subvertical intrusions-related collapse is a likely mechanism affecting small-scale steeply-sloping basaltic volcanoes like Stromboli. Furthermore, our field study combined to modelling results confirms the importance of shallow-dipping intrusions in the morpho-structural evolution of large gently-sloping basaltic volcanoes like Piton de la Fournaise, Etna and Kilauea, with particular regards to flank instability, which can cause catastrophic tsunamis.

La diagnostica sonica nell'arboricoltura ornamentale

Il tomografo sonico è uno strumento di recente applicazione nell’analisi morfo-sintomatica delle alberature. Si tratta di uno strumento che sfrutta la propagazione delle onde sonore nel legno per determinarne la densità e le possibili alterazioni interne. Oltre all’applicazione su larga scala in un parco di Imola, per effettuare una valutazione approfondita di tutti gli esemplari, lo strumento è stato applicato per scopi diversi. In prima analisi è stato utilizzato per valutare stadi precoci di alterazione e l’evoluzione delle patologie interne nel tempo. Successivamente si voleva identificare il percorso di sostanze liquide iniettate con mezzi endoterapici nel tronco, attraverso l’applicazione di tomografia sonica sopra e sotto il punto di iniezione. In ultima analisi è stato effettuato un confronto tra tomografia sonica e risonanza magnetica nucleare per identificare patologie invisibili ai normali strumenti utilizzati nell’analisi della stabilità delle piante.

Conservazione del seme sortato di suino

Gli spermatozoi di suino sottoposti alla procedura di sessaggio mediante citofluorimetria presentano una serie di modificazioni morfo-funzionali che compromettono nel tempo la loro sopravvivenza e la capacità fecondante. Questi spermatozoi, inoltre, a causa della sensibilità ai danni indotti dalla crioconservazione, vengono solitamente conservati allo stato liquido a 15-17°C, con conseguente ulteriore peggioramento nel tempo della qualità delle cellule spermatiche sessate. Lo scopo della ricerca è stato quello di valutare le modificazioni di alcune caratteristiche morfo-funzionali degli spermatozoi in seguito a sex-sorting e conseguente conservazione. Successivamente si è cercato di migliorare i parametri qualitativi del seme sessato mediante l’aggiunta di sostanze antiossidanti e la messa a punto di una nuova metodica di conservazione. I risultati ottenuti hanno evidenziato che la procedura di sessaggio e la conseguente conservazione per 24-26 ore a 15°C hanno indotto un peggioramento significativo delle caratteristiche morfo-funzionali (vitalità, integrità acrosomiale, quantità e distribuzione dell’Hsp70, capacità fecondante). Mentre l’azione degli antiossidanti non si è rivelata efficace nel miglioramento della qualità degli spermatozoi durante le fasi di colorazione e passaggio attraverso il citofluorimetro, l’azione congiunta del plasma seminale e degli antiossidanti superossido-dismutasi ed epigallocatechina-3-gallato ha indotto un miglioramento significativo della vitalità degli spermatozoi. Per la conservazione del seme di suino è stata testata la tecnica di incapsulazione in membrane di alginato di bario che permette, durante l’inseminazione artificiale, un rilascio graduale degli spermatozoi e l’utilizzo di un quantitativo inferiore di materiale seminale. L’applicazione di tale tecnica per la conservazione degli spermatozoi di suino sessati non sembra provocare un calo significativo della vitalità, dell’integrità acrosomiale e dell’efficienza totale di fecondazione rispetto al seme sortato e conservato diluito suggerendo futuri studi in vivo. Una migliore conoscenza dei danni indotti da queste tecnologie e la loro minimizzazione potrà stimolare in futuro l’utilizzo su vasta scala del seme sessato nel suino.

A multiparental cross population for mapping QTL for relevant agronomic traits in durum wheat (Triticum durum Desf.)

Multiparental cross designs for mapping quantitative trait loci (QTL) in crops are efficient alternatives to conventional biparental experimental populations because they exploit a broader genetic basis and higher mapping resolution. We describe the development and deployment of a multiparental recombinant inbred line (RIL) population in durum wheat (Triticum durum Desf.) obtained by crossing four elite cultivars characterized by different traits of agronomic value. A linkage map spanning 2,663 cM and including 7,594 single nucleotide polymorphisms (SNPs) was produced by genotyping 338 RILs with a wheat-dedicated 90k SNP chip. A cluster file was developed for correct allele calling in the framework of the tetraploid durum wheat genome. Based on phenotypic data collected over four field experiments, a multi-trait quantitative trait loci (QTL) analysis was carried out for 18 traits of agronomic relevance (including yield, yield-components, morpho-physiological and seed quality traits). Across environments, a total of 63 QTL were identified and characterized in terms of the four founder haplotypes. We mapped two QTL for grain yield across environments and 23 QTL for grain yield components. A novel major QTL for number of grain per spikelet/ear was mapped on chr 2A and shown to control up to 39% of phenotypic variance in this cross. Functionally different QTL alleles, in terms of direction and size of genetic effect, were distributed among the four parents. Based on the occurrence of QTL-clusters, we characterized the breeding values (in terms of effects on yield) of most of QTL for heading and maturity as well as yield component and quality QTL. This multiparental RIL population provides the wheat community with a highly informative QTL mapping resource enabling the dissection of the genetic architecture of multiple agronomic relevant traits in durum wheat.

Anatomical biomarkers of body composition in oncological population: application and development of artificial intelligences

In the Era of precision medicine and big medical data sharing, it is necessary to solve the work-flow of digital radiological big data in a productive and effective way. In particular, nowadays, it is possible to extract information “hidden” in digital images, in order to create diagnostic algorithms helping clinicians to set up more personalized therapies, which are in particular targets of modern oncological medicine. Digital images generated by the patient have a “texture” structure that is not visible but encrypted; it is “hidden” because it cannot be recognized by sight alone. Thanks to artificial intelligence, pre- and post-processing software and generation of mathematical calculation algorithms, we could perform a classification based on non-visible data contained in radiological images. Being able to calculate the volume of tissue body composition could lead to creating clasterized classes of patients inserted in standard morphological reference tables, based on human anatomy distinguished by gender and age, and maybe in future also by race. Furthermore, the branch of “morpho-radiology" is a useful modality to solve problems regarding personalized therapies, which is particularly needed in the oncological field. Actually oncological therapies are no longer based on generic drugs but on target personalized therapy. The lack of gender and age therapies table could be filled thanks to morpho-radiology data analysis application.