425 research outputs found
Analisi della connettività e della dinamica di crescita di cellule di Purkinje tramite imaging in vitro ed algoritmi computazionali
L’obiettivo di questa tesi è lo studio della connettività e della morfologia neuronale in vitro al fine di comprendere come la patologia dell’autismo alteri lo sviluppo cerebrale e cerebellare.
L’autismo è un disturbo neuronale che danneggia la capacità di una persona di pensare, di provare emozioni, di comunicare e di relazionarsi in maniera appropriata al mondo esterno.
Le ricerche su questa patologia sono iniziate negli anni ’60 quando gli studi neurologici hanno dimostrato che il cervello di persone affette da autismo presenta delle anormalità .
I risultati di questi studi si basano su evidenze macroscopiche. Quello che manca nello stato dell’arte è uno studio dell’evoluzione delle anormalità neuro-strutturali su scala microscopica.
Questo lavoro di tesi si colloca nell’ambito di un progetto che ha lo scopo di affrontare il problema del disordine cerebrale che causa l’autismo a livello microscopico cioè a livello di reti e di singoli neuroni.
Gli studi realizzati vengono effettuati in dinamico cioè seguendo lo sviluppo dei neuroni coltivati in vitro nel tempo.
Il lavoro si basa sulla realizzazione di foto di neuroni primari di topo in vitro a diversi intervalli di tempo e sulla successiva analisi di tali immagini attraverso l’utilizzo di appositi algoritmi implementati in Matlab. Lo scopo è quello di estrarre, dallo studio dei dati ottenuti con l’applicazione del Software, delle caratteristiche metriche e topologiche generali e di vedere come esse variano nel tempo.
Il presente lavoro si è articolato in due fasi. Inizialmente ci si è occupati di proseguire un precedente lavoro di tesi in cui è stato messo a punto un modello in vitro per il mappaggio dei circuiti neurali durante le prime fasi dello sviluppo del cervello.
La seconda fase del lavoro, è quella più consistente ed è la parte centrale della tesi. Basandosi sullo stesso principio di estrazione di variabili nel tempo di cellule primarie, sono state seguite due colture di cellule di Purkinje. La scelta di questo tipo di cellule è dovuta al fatto che, come visto sopra, esse risultano essere danneggiate nei soggetti autistici e quindi molto diverse dalla norma.
I dati ottenuti sono stati poi analizzati per cercare di estrarre delle informazioni di carattere generale comuni allo sviluppo di tutte le cellule.
Per il momento sono stati presi in considerazione solamente neuroni normali. Solo dopo sarà effettivamente possibile, esaminando lo sviluppo e la morfologia di neuroni ottenuti da dei modelli animali dell’autismo, sulla base di un confronto con i risultati che otterremo in questa tesi, rilevare quali possano essere le alterazioni morfologiche e di connettività alla base dell’autismo e comprendere come queste influenzino l’iniziale sviluppo anormale del cervello
Olfactory Testing in Frontotemporal Dementia: A Literature Review
Frontotemporal dementia (FTD) is a heterogeneous disorder featuring language impairment, personality changes, and executive defects, often due to the frontotemporal lobar degeneration (FTLD). Both FTD and FTLD are often associated with olfactory impairment, early biomarker for neurodegeneration, which can be evaluated with different techniques, among which low-cost olfactory tests are widely used. Therefore, we conducted a review of the literature focusing on papers published between January 1, 2007, and June 12, 2017, investigating the usefulness of olfactory testing in FTD/FTLD. A general decrease in the olfactory identification ability was seen in most of the articles and, taken together with a preserved odor discrimination, reveals a higher order impairment, possibly linked to cognitive decrease or language impairments, and not to a specific deficit of the olfactory system. This evidence could represent a useful add-on to the current literature, increasing the diagnostic value of olfactory assessment, particularly in cases where differential diagnosis is difficult
Qrs detection based on medical knowledge and cascades of moving average filters
Heartbeat detection is the first step in automatic analysis of the electrocardiogram (ECG). For mobile and wearable devices, the detection process should be both accurate and computationally efficient. In this paper, we present a QRS detection algorithm based on moving average filters, which affords a simple yet robust signal processing technique. The decision logic considers the rhythmic and morphological features of the QRS complex. QRS enhancing is performed with channel-specific moving average cascades selected from a pool of derivative systems we designed. We measured the effectiveness of our algorithm on well-known benchmark databases, reporting F1 scores, sensitivity on abnormal beats and processing time. We also evaluated the performances of other available detectors for a direct comparison with the same criteria. The algorithm we propose achieved satisfying performances on par with or higher than the other QRS detectors. Despite the performances we report are not the highest that have been published so far, our approach to QRS detection enhances computational efficiency while maintaining high accuracy
Multiple approach to identify bacteria into archaeological waterlogged wood
This study was carried out in collaboration with Soprintendenza del Mare (SM) that started, since 2004,
to plan and realize underwater archaeological parks, such as in the Sicilian islands of Pantelleria (Gadir),
Levanzo (Cala Minnola), Ustica (Falconiera), Panarea (Basiluzzo) and Filicudi (Capo Graziano). In situ conservation,
as well as virtual exhibitions of the same topics, can contribute to ensure the protection and
best fruition of underwater cultural heritage. The focus of this study was the identification of bacterial
colonies in waterlogged wood samples from the rostrum of a excellent workmanship, that is very likely
one of the wrecks attributed to Sextus Pompey fleet (36 BC) and discovered in Acqualadroni, Messina,
Sicily, Italy (2008). Samples were analyzed by light and Scanning Electron Microscopy (SEM), in vitro culture
and molecular technique (DNA base techniques). The results, focused on bacterial consortia, allowed
us to reveal the presence of Pseudomonas sp., Sphingomonas sp., Xanthomonas sp. besides Marinobacter sp.
and Desulforudis audaxviator. A prompt and accurate characterization of bacterial colonization represents
one of the preliminary step in preservation/restoration projects, especially for waterlogged wood since
the metabolic activity of specific bacteria induce and accelerate the deterioration processes. Although it
is reported in a case study, this multiple approach is useful for reveal and identify bacterial colonizing
both organic and inorganic artifacts.This study was carried out in collaboration with Soprintendenza del Mare (SM) that started, since 2004,
to plan and realize underwater archaeological parks, such as in the Sicilian islands of Pantelleria (Gadir),
Levanzo (Cala Minnola), Ustica (Falconiera), Panarea (Basiluzzo) and Filicudi (Capo Graziano). In situ conservation,
as well as virtual exhibitions of the same topics, can contribute to ensure the protection and
best fruition of underwater cultural heritage. The focus of this study was the identification of bacterial
colonies in waterlogged wood samples from the rostrum of a excellent workmanship, that is very likely
one of the wrecks attributed to Sextus Pompey fleet (36 BC) and discovered in Acqualadroni, Messina,
Sicily, Italy (2008). Samples were analyzed by light and Scanning Electron Microscopy (SEM), in vitro culture
and molecular technique (DNA base techniques). The results, focused on bacterial consortia, allowed
us to reveal the presence of Pseudomonas sp., Sphingomonas sp., Xanthomonas sp. besides Marinobacter sp.
and Desulforudis audaxviator. A prompt and accurate characterization of bacterial colonization represents
one of the preliminary step in preservation/restoration projects, especially for waterlogged wood since
the metabolic activity of specific bacteria induce and accelerate the deterioration processes. Although it
is reported in a case study, this multiple approach is useful for reveal and identify bacterial colonizing
both organic and inorganic artifacts
Post-traumatic pituitary apoplexy: Case presentation and review of literature
Abstract Pituitary apoplexy is a dramatic condition that can occur spontaneously or triggered by various precipitating factors. Head trauma is a rare but well-recognized cause of apoplectics events. We present the case of an 81-year-old woman, with negative past medical history and under antiplatelet agents, who experienced an isolated VI cranial nerve palsy 24 h after a mild head trauma. Early brain CT revealed an unknown pituitary lesion without signs of intralesional bleeding. Only late brain MRI imaging revealed pituitary apoplexy together with a subarachnoid hemorrhage. After aggravation of neurological condition the patient, undergo endoscopic transsphenoidal decompression of cranial nerves with rapid deficits improvement. Our aim is to share our experience and to propose the first critical review of all cases of post-traumatic pituitary apoplexy described in literature. We also try to suggest some management advice for post traumatic pituitary apoplexy
Novel methodologies and technologies for the multiscale and multimodal study of Autism Spectrum Disorders (ASDs)
The aim of this PhD thesis was the development of novel bioengineering tools and methodologies that provide a support in the study of ASDs.
ASDs are very heterogeneous disturbs and their abnormalities are present both at local and global level. For this reason a multimodal and multiscale approach was followed.
The analysis of microstructure was executed on single Purkinje neurons in culture and on organotypic slices extracted from cerebella of GFP wild-type mice and animal models of ASDs. A methodology for the non-invasive imaging of neurons during their growth was set up and a software called NEMO (NEuron MOrphological analysis tool) for the automatic analysis of morphology and connectivity was developed.
Microstructure properties can be inferred also in vivo through the quite recent technique of Diffusion Tensor Imaging (DTI). DTI studies in ASDs are based on the hypothesis that the disorder involves aberrant brain connectivity and disruption of white matter tracts between regions implicated in social functioning. In this study DTI was used to investigate structural abnormalities in the white matter structure of young children with ASDs. Moreover the neurostructural bases of echolalia were investigated.
The functionality of the brain was analyzed through Functional Magnetic Resonance Imaging (fMRI) using a novel task based on face processing of human, android and robotic faces. A case-control study was performed in order to study how the face processing network is altered in ASDs and how robots are differently processed in ASDs and control groups.
Measurements characterizing physiology and behavior of ASD children were also collected using an innovative platform called FACE-T (FACE-Therapy). FACE-T consists of a specially equipped room in which the child, wearing unobtrusive devices for recording physiological and behavioral data as well as gaze information, can interact with an android (FACE, Facial Automaton for Conveying Emotions) and a therapist.
The focus was on ECG, as from the analysis of power spectrum density of ECG it is possible to extract features related to the autonomic nervous system that is correlated with brain functionality.
These studies give new insights in the study of ASDs exploring aspects not yet addressed. Moreover the methodologies and tools developed could help in the objective characterization of ASD subjects and in the definition of a personalized therapeutic protocol for each child
EXOTIC INSECT PESTS: THE IMPACT OF THE RED PALM WEEVIL ON NATURAL AND CULTURAL HERITAGE IN PALERMO (ITALY)
The impact of invasive exotic pests is increasingly recognised as a global issue. A global strategy to address the exotic pest problem is beginning to evolve, albeit slowly. The International Plant Protection Convention (FAO) has begun the process of harmonizing standards for pest risk analysis to minimise the spread of exotic pests without adversely impacting global trade. However if the impacts of insect invasive species on human health and on agriculture have attracted worldwide attention, researchers and policymakers address directly the connection between invasive species and damage to natural and cultural heritages. The cost of these losses is generally neglected or underestimated. Various attempts have been made to treat the plants or the wood that affected by invasive species. But studies of the links between these pests and their effects on natural biodiversity and heritage, in botanical and historical gardens, are largely lacking in the literature. This paper examines categories of pest risk threatening the Mediterranean, with special emphasis on the author’s homeland. We report the case of the invasive species Rhynchophorus ferrugineus (Red Palm Weevil, RPW) recently introduced into Europe. With an interdisciplinary approach, and by focusing on he situation in Sicily, we analyse how the RPW could be considered not only a pest impacting palm trees, but also natural and cultural assets and heritage
UN CIMITERO RUPESTRE DI EPOCA TARDOANTICA IN SICILIA: STUDIO INTERDISCIPLINARE DELL’AMBIENTE E DEI REPERTI ARCHEOLOGICI.
Catalysis in Supramolecular Systems: the Case of Gel Phases
Supramolecular gels are a fascinating class of materials, originated by the self-assembly of low molecular weight molecules. Underpinned by non-covalent interactions, they find application in a diverse range of fields. Among these, supramolecular gels can be considered as organized, non-conventional reaction media, able to influence reactivity in a radically different way, compared with what happens in solution. This short review will focus on this aspect, covering literature from 2010 onwards, addressing the application of supramolecular gels as reaction media. In particular, in the first section we explore organocatalytic reactions in gel phase, with wide synthetic relevance, such as aldol and Mannich reactions as well as Friedel Crafts or ester hydrolysis processes. Subsequently, focus is laid on metal-catalysed reactions, among which relevance is given to widely used reactions like cross-coupling and click reactions. Then, the final sections describe the use of supramolecular gels as reaction media for photo- and biocatalysed processes
IMPOVERISHMENT OF SICILIAN (ITALY) HISTORICAL AND CULTURAL ASSETS BY AN ALIEN INSECT SPECIES: THE CASE OF THE RED PALM WEEVIL.
Alien invasive species (IAS) have a disastrous impact on the biodiversity, cultural heritage and economy of a geographic area. The case of the Red Palm Weevil (RPW), an IAS that attacks the non-native palm species Phoenix canariensis, but also native species Chaemerops humilis, especially in urban and peri-urban areas, is reported. These palm trees have played an important role in Sicilian history and cultural heritage since the period of the Arab invasion. The accidental introduction of the RPW has remarkably changed the Sicilian panorama. In this study the chronology and the severity of the effects of RPW on palms so far detected, is reported. In only 7 years the RPW has drastically changed the aesthetic value and perception of the natural and cultural heritage in Sicily. Results suggest that the Precautionary Principle should be applied when IAS may impact on natural and cultural heritage
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