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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
191

La cardiomiopatia aritmogena come causa di scompenso cardiaco e trapianto di cuore / Arrhythmogenic cardiomyopathy as cause of severe heart failure leading to heart transplantation

Graziosi, Maddalena <1979> 12 May 2014 (has links)
Scopo dello studio: la cardiomiopatia aritmogena (CA) è conosciuta come causa di morte improvvisa, la sua relazione con lo scompenso cardiaco (SC) è stata scarsamente indagata. Scopo dello studio è la definizione della prevalenza e incidenza dello SC, nonché della fisiopatologia e delle basi morfologiche che conducono i pazienti con CA a SC e trapianto di cuore. Metodi: abbiamo analizzato retrospettivamente 64 pazienti con diagnosi di CA e confrontato i dati clinici e strumentali dei pazienti con e senza SC (NYHA III-IV). Abbiamo analizzato i cuori espiantati dei pazienti sottoposti a trapianto presso i centri di Bologna e Padova. Risultati: la prevalenza dello SC alla prima osservazione era del 14% e l’incidenza del 2,3% anno-persona. Sedici pazienti (23%) sono stati sottoposti a trapianto. I pazienti con SC erano più giovani all’esordio dei sintomi (46±16 versus 37±12 anni, p=0.04); il ventricolo destro (VD) era più dilatato e ipocinetico all’ecocardiogramma (RVOT 41±6 versus 37±7 mm, p=0.03; diametro telediastolico VD 38±11 versus 28±8 mm, p=0.0001; frazione di accorciamento 23%±7 versus 32%±11, p= 0.002). Il ventricolo sinistro (VS) era lievemente più dilatato (75±29 ml/m2 versus 60±19, p= 0.0017) e globalmente più ipocinetico (frazione di eiezione = 35%±14 versus 57%±12, p= 0.001). Il profilo emodinamico dei pazienti sottoposti a trapianto era caratterizzato da un basso indice cardiaco (1.8±0.2 l/min/m2) con pressione capillare e polmonare tendenzialmente normale (12±8 mmHg e 26±10 mmHg). L’analisi dettagliata dei 36 cuori dei pazienti trapiantati ha mostrato sostituzione fibro-adiposa transmurale nel VD e aree di fibrosi nel VS. Conclusioni: Nella CA lo SC può essere l’unico sintomo alla presentazione e condurre a trapianto un rilevante sottogruppo di pazienti. Chi sviluppa SC è più giovane, ha un interessamento del VD più severo accanto a un costante interessamento del VS, solo lievemente dilatato e ipocinetico, con sostituzione prevalentemente fibrosa. / Purpose: Arrythmogenic right ventricular cardiomyopathy (ARVC) is predominantly known as a cause of sudden death in the young, whereas the relationship with heart failure (HF) has been scarcely investigated. We aimed this study to evaluate prevalence, incidence, pathophysiology and morphologic basis of ARVC leading to severe HF. Methods: We retrospectively analysed 64 patients with ARVC evaluated at a single referral centre. We compared the clinical and instrumental findings of ARVC patients with/without severe HF (NYHA III-IV) at first evaluation or during follow up. We analysed the explanted hearts of patients who underwent heart transplantation in two referral centre, Bologna and Padua University. Results: Severe HF was present in 9 patients at presentation (prevalence=14%) and occurred in 10 during follow up (incidence=2.3% person-years). Sixteen patients (23%) required heart transplantation. Patients with advanced HF were younger at symptom onset (46±16 versus 37±12 years, p=0.04); right ventricle (RV) was larger and more hypokinetic at echocardiography (RVOT 41±6 versus 37±7 mm, p=0.03; RV end diastolic diameter 38±11 versus 28±8 mm, p=0.0001; fractional shortening area 23%±7 versus 32%±11, p= 0.002). Left ventricle (LV) was slightly more dilated (75±29 ml/m2 versus 60±19, p= 0.0017) and globally hypokinetic (Ejection Fraction = 35%±14 versus 57%±12, p= 0.001). The hemodynamic profile of patients who underwent cardiac transplantation showed low cardiac index (1.8±0.2 l//min/m2) with nearly normal capillary wedge and pulmonary pressure (12±8 mmHg and 26±10 mmHg). A detailed histological analysis of 36 explanted hearts showed extensive fibro-fatty infiltration of the RV and isolated or confluent areas of LV fibrosis. Conclusions: In ARVC, HF can be the only symptom at presentation and leads to heart transplantation in a relevant subset of patients. Patients who develop advanced HF are younger, have more severe RV involvement associated with slight dilation and global hypokinesia of the LV, due to fibrotic infiltration.
192

The search for Multiple Myeloma Stem cells: molecular characterization and self-renewal mechanisms involved in the disease persistence

Martello, Marina <1983> 23 January 2014 (has links)
The existence of Multiple Myeloma Stem cells (MMSCs)is supposed to be one of the major causes of MM drug-resistance. However, very little is known about the molecular characteristics of MMSCs, even if some studies suggested that these cells resembles the memory B cells. In order to molecularly characterize MMSCs, we isolated the 138+138- population. For each cell fraction we performed a VDJ rearrangement analysis. The complete set of aberrations were performed by SNP Array 6.0 and HG-U133 Plus 2.0 microarray analyses (Affymetrix). The VDJ rearrangement analyses confirmed the clonal relationship between the 138+ clone and the immature clone. Both BM and PBL 138+ clones showed exactly the same genomic macroalterations. In the BM and PBL 138-19+27+ cell fractions several micro-alterations (range: 1-350 Kb) unique of the memory B cells clone were highlighted. Any micro-alterations detected were located out of any genomic variants region and are presumably associated to the MM pathogenesis, as confirmed by the presence of KRAS, WWOX and XIAP genes among the amplified regions. To get insight into the biology of the clonotypic B cell population, we compared the gene expression profile of 8 MM B cells samples 5 donor B cells vs, thus showing a differential expression of 11480 probes (p-value: <0,05). Among the self-renewal mechanisms, we observed the down-regulation of Hedgehog pathway and the iperactivation of Notch and Wnt signaling. Moreover, these immature cells showed a particular phenotype correlated to resistance to proteasome inhibitors (IRE1α-XBP1: -18.0; -19.96. P<0,05). Data suggested that the MM 138+ clone might resume the end of the complex process of myelomagenesis, whereas the memory B cells have some intriguing micro-alterations and a specific transcriptional program, supporting the idea that these post germinal center cells might be involved in the transforming event that originate and sustain the neoplastic clone.
193

Targeting the p53–MDM2 interaction by the small-molecule MDM2 antagonist Nutlin-3a: a new challenged target therapy in adult Philadelphia positive acute lymphoblastic leukemia patients

Trino, Stefania <1986> 23 January 2014 (has links)
The human p53 tumor suppressor, known as the “guardian of the genome”, is one of the most important molecules in human cancers. One mechanism for suppressing p53 uses its negative regulator, MDM2, which modulates p53 by binding directly to and decreasing p53 stability. In testing novel therapeutic approaches activating p53, we investigated the preclinical activity of the MDM2 antagonist, Nutlin-3a, in Philadelphia positive (Ph+) and negative (Ph-) leukemic cell line models, and primary B-Acute lymphoblastic leukemia (ALL) patient samples. In this study we demonstrated that treatment with Nutlin-3a induced grow arrest and apoptosis mediated by p53 pathway in ALL cells with wild-type p53, in time and dose-dependent manner. Consequently, MDM2 inhibitor caused an increase of pro-apoptotic proteins and key regulators of cell cycle arrest. The dose-dependent reduction in cell viability was confirmed in primary blast cells from Ph+ ALL patients with the T315I Bcr-Abl kinase domain mutation. In order to better elucidate the implications of p53 activation and to identify biomarkers of clinical activity, gene expression profiling analysis in sensitive cell lines was performed. A total of 621 genes were differentially expressed (p < 0.05). We found a strong down-regulation of GAS41 (growth-arrest specific 1 gene) and BMI1 (a polycomb ring-finger oncogene) (fold-change -1.35 and -1.11, respectively; p-value 0.02 and 0.03, respectively) after in vitro treatment as compared to control cells. Both genes are repressors of INK4/ARF and p21. Given the importance of BMI in the control of apoptosis, we investigated its pattern in treated and untreated cells, confirming a marked decrease after exposure to MDM2 inhibitor in ALL cells. Noteworthy, the BMI-1 levels remained constant in resistant cells. Therefore, BMI-1 may be used as a biomarker of response. Our findings provide a strong rational for further clinical investigation of Nutlin-3a in Ph+ and Ph-ALL.
194

Next-Generation Sequencing-Based Mutations Scanning Strategy of the BCR-ABL Kinase Domain in Patients with PhiladelPhia-Chromosome Positive Leukemias Treated with Tyrosine Kinase Inhibitors

De Benedittis, Caterina <1983> 22 January 2015 (has links)
In chronic myeloid leukemia and Philadelphia-positive acute lymphoblastic leukemia patients resistant to tyrosine kinase inhibitors (TKIs), BCR-ABL kinase domain mutation status is an essential component of the therapeutic decision algorithm. The recent development of Ultra-Deep Sequencing approach (UDS) has opened the way to a more accurate characterization of the mutant clones surviving TKIs conjugating assay sensitivity and throughput. We decided to set-up and validated an UDS-based for BCR-ABL KD mutation screening in order to i) resolve qualitatively and quantitatively the complexity and the clonal structure of mutated populations surviving TKIs, ii) study the dynamic of expansion of mutated clones in relation to TKIs therapy, iii) assess whether UDS may allow more sensitive detection of emerging clones, harboring critical 2GTKIs-resistant mutations predicting for an impending relapse, earlier than SS. UDS was performed on a Roche GS Junior instrument, according to an amplicon sequencing design and protocol set up and validated in the framework of the IRON-II (Interlaboratory Robustness of Next-Generation Sequencing) International consortium.Samples from CML and Ph+ ALL patients who had developed resistance to one or multiple TKIs and collected at regular time-points during treatment were selected for this study. Our results indicate the technical feasibility, accuracy and robustness of our UDS-based BCR-ABL KD mutation screening approach. UDS was found to provide a more accurate picture of BCR-ABL KD mutation status, both in terms of presence/absence of mutations and in terms of clonal complexity and showed that BCR-ABL KD mutations detected by SS are only the “tip of iceberg”. In addition UDS may reliably pick 2GTKIs-resistant mutations earlier than SS in a significantly greater proportion of patients.The enhanced sensitivity as well as the possibility to identify low level mutations point the UDS-based approach as an ideal alternative to conventional sequencing for BCR-ABL KD mutation screening in TKIs-resistant Ph+ leukemia patients
195

Histone deacetylase inhibitors in adult patients with diffuse large b-cell lymphoma relapsed/refractory: a phase II study with Panobinostat / Gli inibitori dell'istone deacetilasi nel trattamento del linfoma non hodgkin diffuso a grandi cellule ricaduto/refrattario dell'adulto: studio di fase II con Panobinostat

Pellegrini, Cinzia <1980> 22 January 2015 (has links)
Backgrounds:Treatment of patients with relapsed/refractory (R/R) diffuse large B-cell lymphoma (DLBCL) not eligible to high dose therapy represents an unmet medical need. Panobinostat showed encouraging therapeutic activity in studies conducted in lymphoma cell lines and in vivo in patients with advanced hematologic malignancies.Purpose:FIL-PanAL10 (NCT01523834) is a phase II, prospective multicenter trial of the Fondazione Italiana Linfomi (FIL) to evaluate safety and efficacy of single agent Panobinostat as salvage therapy for R/R DLBCL patients and to evaluate a possible relationships between response and any biological features. Patients and Methods:Patients with R/R DLBCL were included. The treatment plan included 6 induction courses with Panobinostat monotherapy followed by other 6 courses of consolidation. The primary objective was to evaluate Panobinostat activity in terms of overall response (OR); secondary objectives were: CR rate, time to response (TTR), progression-free survival (PFS), safety and feasibility of Panobinostat. We included evaluation of the impact of pharmacogenetics, immunohistochemical patterns and patient’s specific gene expression and mutations as potential predictors of response to Panobinostat as explorative objectives. To this aim a pre-enrollment new tissue biopsy was mandatory. ResultsThirty-five patients, 21 males (60%), were enrolled between June 2011 and March 2014. At the end of induction phase, 7 responses (20%) were observed, including 4 CR (11%), while 28 patients (80%) discontinued treatment due to progressive disease (PD) in 21 (60%) or adverse events in 7 (20%). Median TTR in 9 responders was 2.6 months (range 1.8-12). With a median follow up of 6 months (range 1-34), the estimated 12 months PFS and OS were 27% and 30.5%, respectively. Grade 3-4 thrombocytopenia and neutropenia were the most common toxicities (in 29 (83%) and 12 (34%) patients, respectively. Conclusions The results of this study indicate that Panobinostat might be remarkably active in some patients with R/R DLBCL, showing durable CR
196

Nuovi metodi di diagnosi precoce dei fallimenti di protesi d'anca con accoppiamento articolare ceramica-ceramica / New methods for early diagnosis of ceramic failure in ceramic on ceramic hip prosthesis

Traina, Francesco <1973> 22 January 2015 (has links)
L’accoppiamento articolare in ceramica è sempre più utilizzato in chirurgia protesica dell’anca per le sue eccellenti proprietà tribologiche. Tuttavia la fragilità della ceramica è causa di fallimenti meccanici. Abbiamo quindi condotto una serie di studi al fine di individuare un metodo efficace di diagnosi precoce del fallimento della ceramica. Abbiamo analizzato delle componenti ceramiche espiantate e abbiamo trovato un pattern di usura pre-frattura che faceva supporre una dispersione di particelle di ceramica nello spazio articolare. Per la diagnosi precoce abbiamo validato una metodica basata sulla microanalisi del liquido sinoviale. Per validare la metodica abbiamo eseguito un agoaspirato in 12 protesi ben funzionanti (bianchi) e confrontato i risultati di 39 protesi con segni di rottura con quelli di 7 senza segni di rottura. Per individuare i pazienti a rischio rottura i dati demografici di 26 pazienti con ceramica rotta sono stati confrontati con 49 controlli comparabili in termini demografici, tipo di ceramica e tipo di protesi. Infine è stata condotta una revisione sistematica della letteratura sulla diagnosi della rottura della ceramica. Nell’aspirato la presenza di almeno 11 particelle ceramiche di dimensioni inferiori a 3 micron o di una maggiore di 3 micron per ogni campo di osservazione sono segno di rottura della ceramica. La metodica con agoaspirato ha 100% di sensibilità e 88 % di specificità nel predire rotture della ceramica. Nel gruppo delle ceramiche rotte è stato trovato un maggior numero di malposizionamenti della protesi rispetto ai controlli (p=0,001). Il rumore in protesi con ceramica dovrebbe sollevare il sospetto di fallimento ed indurre ad eseguire una TC e un agoaspirato. Dal confronto con la letteratura la nostra metodica risulta essere la più efficace. / Ceramic is increasingly used in total hip replacement for its excellent tribological properties. However, the brittleness of ceramics is of concern and mechanical failures are reported. We conducted a series of studies in order to identify an effective method of early diagnosis of ceramic failure. We have analyzed 20 ceramic components explanted and found a pattern of wear that would suggest a dispersion of ceramic particles in the joint space. We therefore investigated whether isolation, observation at scanning electron microscopy, and chemical identification with microanalysis of particles from synovial fluid could be predictive of ceramic damage. Firstly, the level of ‘‘physiological wear’’ of well functioning hip prostheses was assessed with this method, then the test was validated as diagnostic method for liner fracture. Twelve asymptomatic patients were enrolled to demonstrate the first aim; 39 cases of noisy hip, and 7 cases of pending failure not related to ceramic were enrolled for the second aim. To detect risk factors for ceramic liner fractures we compared 26 ceramic hips revised because of ceramic liner fracture with 49 well-functioning hips. Finally a systematic review was done to compare our results with those reported in the litterature. In the aspirate the presence of at least 11 ceramic particles of size less than 3 microns or the presence of one greater than 3 microns for each field of observation are a sign of ceramic failure. The method with fine needle aspiration has 100% sensitivity and 88% specificity in predicting breakage of the ceramic. A cup anteversion angle out of the optimal range of 15 ̊+/-10 ̊ was found to be a risk factor for ceramic liner fracture. There are no other diagnostic methodologies described in the literature as specific and sensible as the one we have proposed.
197

Espressione dell'Enzima ad Azione Immunoregolatoria Indoleamina 2,3-Diossigenasi nella Leucemia Mieloide Acuta dell'Adulto: correlazioni Clinico-Biologiche / Expression of the Immunoregulatory Enzyme Indoleamine 2,3-Dioxygenase in Adult Acute Myeloid Leukemia: Clinical and Biologycal Correlations

Parisi, Sarah <1983> 10 May 2012 (has links)
L’enzima IDO interviene nella via di degradazione del triptofano, essenziale per la vita cellulare; l’iperespressione di IDO favorisce la creazione di un microambiente immunotollerante. Nelle LAM IDO è funzionalmente attivo nelle cellule blastiche e determina l’acquisizione di un fenotipo regolatorio da parte delle cellule T alloreattive; l’espressione della proteina aumenta in modo consensuale con l’evoluzione clinica della patologia. Scopo della Tesi è indagare l’esistenza di una correlazione tra l’iperespressione di IDO da parte delle cellule leucemiche, le caratteristiche di rischio alla diagnosi e l’outcome dei pazienti. Sono stati esaminati 45 pazienti adulti affetti da LAM afferiti all’Istituto di Ematologia di Bologna. I pazienti sono stati stratificati a seconda di: età di insorgenza della leucemia, secondarietà a Mielodisplasia o radio chemioterapia, iperleucocitosi, citogenetica, biologia molecolare (sono state valutate le alterazioni a carico dei geni FLT3 ed NPM). I pazienti sono stati analizzati per l’espressione del gene IDO mediante RT-PCR, seguita da Western Blot, allo scopo di stabilire la presenza di una proteina attiva; successivamente si è proceduto a verificare l’esistenza di una correlazione tra l’espressione di IDO e le caratteristiche di rischio alla diagnosi per identificare una relazione tra l’espressione del gene ed un subset di pazienti a prognosi favorevole o sfavorevole. Dei 45 pazienti adulti affetti da LAM il 28,9% è risultato negativo per l’espressione di IDO, mentre il rimanente 71,1% è risultato positivo ed è stato suddiviso in tre ulteriori categorie, in base ai livelli di espressione. I dati non sembrano al momento suggerire l’esistenza di una correlazione tra l’espressione di IDO e le caratteristiche di rischio alla diagnosi. Nel gruppo di pazienti ad elevata espressione di IDO si riscontra un rate di resistenza alla chemioterapia di induzione più elevato, con una quota di pazienti resistenti pari al 71,4%, contro il 23,1% nel gruppo di pazienti IDO-negativi. / Tryptophan is an essential amino-acid required for protein synthesis and for cell proliferation. IDO is an eme-containing enzyme that catalyzes the rate-limiting step in tryptophan degradation along the kynurenine pathway and its overexpression is known to be involved in immune tolerance induction. IDO is functionally active in Acute Myeloid Leukemia tumor cells and it acts by inducing the transformation of T-cells into regulatory T-cells. Several observations demonstrated that IDO expression increases along with disease progression. The object of the work is to establish a correlation between IDO expression by leukemic cells, risk factors at diagnosis and patients’ outcome. Adult AML patients from the Hematology Institute “L. and A. Seràgnoli” in Bologna were analyzed for risk characteristics at diagnosis and for IDO expression. Patients were stratified according to: age at diagnosis, de novo or secondary disease (pre-existing myelodysplastic syndrome or radio-chemotherapy), hyperleucocytosis, cytogenetics (on the basis of cytogenetic characteristics patients were divided into low, intermediate or high risk group), molecular biology (the presence of FLT3 and NPM alterations was studied). These patients were analyzed for IDO expression by RT-PCR and the presence of a functionally active IDO protein was established by Western Blotting analysis. Eventually the correlation between IDO expression, risk factors at diagnosis and patients’ outcome was evaluated. Thirteen out of the 45 analyzed patients (28,9%) resulted to be IDO-negative, 71,1% being IDO-positive. Positive patients were divided into three different subgroups according to the IDO level. No significant differences in the recurrence of prognostic characteristics at diagnosis between IDO-negative and IDO-positive patients were experienced. Intriguingly, it has been found that refractory patients were 71,4% among patients who express IDO at high level and 23,1% among IDO-negative patients.
198

Stimolazione precoce della consolidazione ossea in pazienti con frattura di gamba attraverso campi elettromagnetici pulsati basata su un algoritmo predittivo del rischio diritardo di consolidazione ossea (ARRCO – Algoritmo Rischio Ritardo Consolidazione Ossea – IGEA®). / Early electromagnetic bone growth stimulation (Pulsing Low-frequency Electromagnetic Fields - PEMF) in patients with leg fracture based on predictive score for risk of delayed healing (ARRCO – Algoritmo Rischio Ritardo Consolidazione Ossea).

Nanni, Matteo <1979> 23 January 2014 (has links)
E' stato sviluppato un algoritmo predittivo del rischio di consolidazione ossea (ARRCO – Algoritmo Rischio Ritardo Consolidazione Ossea - IGEA, Carpi, Italy) che combina diversi fattori correlati al rischio di ritardata o mancata guarigione di una frattura. Questo algoritmo ha permesso di idntificare una popolazione di pazienti affetti da fratture con aumentato rischio di ritardo di consolidazione o mancata guarigione. Questi pazienti sono stati sottoposti precocemente a stimolazione biofisica precoce mediante Campi Elettromagnetici Pulsati a bassa frequenza (CEMP), ottenendo la guarigione della frattura nella maggior parte dei casi e in tempi considerati fisiologici. Pertanto in un gruppo selezionato di pazienti, il trattamento può essere indirizzato all'applicazione precoce di CEMP, al fine di promuovere la consolidazione ossea di una frattura "a richio", il cui trattamento richiederebbe altrimenti tempi più prolungati e un costo virtuale maggiore dell'intero trattamento sanitario. / A predictive score for risk of delayed healing (ARRCO – Algoritmo Rischio Ritardo Consolidazione Ossea - IGEA, Carpi, Italy) has been developed in order to consider and combine different risk factors influencing the healing of a fracture, calculating a score correlated with healing potential, time of healing and risk of delayed healing or non-union. The ARRCO score provided a simple and effective tool for the orthopaedic surgeons to early identify fractures presenting risk of delayed healing. In these cases early application of Pulsing Low-frequency Electromagnetic Fields (PEMF) was performed, obtaining bone healing in most of cases reducing the time of healing. Therefore in a selected group of patients affected by "fractures at risk", the treatment may be directed to early application of electromagnetic bone growth stimulation with PEMF, in order to promote healing of the fracture, reducing consequently the time and the virtual cost of the treatment.
199

Reconstructive Microsurgery and Tissue Engineering in Musculo-Skeletal Oncology - Innovative Techniques

Di Bella, Claudia <1978> 03 May 2012 (has links)
Tumors involving bone and soft tissues are extremely challenging situations. With the recent advances of multi-modal treatment, not only the type of surgery has moved from amputation to limb-sparing procedures, but also the survivorship has improved considerably and reconstructive techniques have the goal to allow a considerably higher quality of life. In bone reconstruction, tissue engineering strategies are the main area of research. Re-vascularization and re-vitalisation of a massive allograft would considerably improve the outcome of biological reconstructions. Using a rabbit animal model, in this study we showed that, by implanting a vascular pedicle inside a weight bearing massive cortical allograft, the bone regeneration inside the allograft was higher compared to the non-vascularized implants, given the patency of the vascular pedicle. Improvement in the animal model and the addition of Stem Cells and Growth factors will allow a further improvement in the results. In soft tissue tumors, free and pedicled flaps have been proven to be of great help as reconstruction strategies. In this study we analyzed the functional and overall outcome of 14 patients who received a re-innervated vascularized flap. We have demonstrated that the use of the innovative technique of motor re-innervated muscular flaps is effective when the resection involves important functional compartments of the upper or lower limb, with no increase of post-operative complications. Although there was no direct comparison between this type of reconstruction and the standard non-innervated reconstruction, we underlined the remarkable high overall functional scores and patient satisfaction following this procedure.
200

Caratterizzazione genomica di virus influenzali suini in Italia mediante next generation sequencing / Genomic characterization of swine influenza viruses in Italy using NGS technology

Zaccaria, Guendalina <1985> 17 April 2015 (has links)
I sottotipi H1N1, H1N2 e H3N2 di influenza A virus sono largamente diffusi nella popolazione suina di tutto il mondo. Nel presente lavoro è stato sviluppato un protocollo di sequenziamento di c.d. nuova generazione, su piattaforma Ion Torrent PGM, idoneo per l’analisi di tutti i virus influenzali suini (SIV). Per valutare l’evoluzione molecolare dei SIV italiani, sono stati sequenziati ed analizzati mediante analisi genomica e filogenetica un totale di sessantadue ceppi di SIV appartenenti ai sottotipi H1N1, H1N2 e H3N2, isolati in Italia dal 1998 al 2014. Sono stati evidenziati in sei campioni due fenomeni di riassortimento: tutti i SIV H1N2 esaminati presentavano una neuraminidasi di derivazione umana, diversa da quella dei SIV H1N2 circolanti in Europa, inoltre l’emoagglutinina (HA) di due isolati H1N2 era originata dal riassortimento con un SIV H1N1 avian-like. L’analisi molecolare dell’HA ha permesso di rivelare un’inserzione di due amminoacidi in quattro SIV H1N1 pandemici e una delezione di due aminoacidi in quattro SIV H1N2, entrambe a livello del sito di legame con il recettore cellulare. E’ stata inoltre evidenziata un’elevata omologia di un SIV H1N1 con ceppi europei isolati negli anni ’80, suggerendo la possibile origine vaccinale di questo virus. E’ stato possibile, in aggiunta, applicare il nuovo protocollo sviluppato per sequenziare un virus influenzale aviare altamente patogeno trasmesso all’uomo, direttamente da campione biologico. La diversità genetica nei SIV esaminati in questo studio conferma l’importanza di un continuo monitoraggio della costellazione genomica dei virus influenzali nella popolazione suina. / Three major swine influenza virus (SIV) subtypes (H1N1, H1N2, and H3N2) are currently identified in pigs worldwide. In this study, a protocol able to sequence all SIV subtypes using the Ion Torrent next generation sequencing technology was developed. Moreover, to investigate the genetic characteristics and the molecular evolution of Italian SIV circulating strains, we conducted genomic and phylogenetic analysis for each segment of sixty-two SIVs isolated in Italy between 1998 and 2014 comprising H1N1, H1N2 and H3N2 strains. Two independent reassortment events in six SIV strains were detected. H1N2 SIVs showed the introduction of a human-like neuraminidase, different from the homologous of circulating H1N2 detected in Europe from swine. Two of these reassortant H1N2 strains contained an avian-like hemagglutinin (HA). Analysis of HA revealed a two-amino acid insertion in four H1N1 pandemic strains and a two-amino acid deletion in four H1N2 strains, both at the HA receptor binding site. High nucleotide identity between an H1N1 of this study and European field strains isolated in the 80s was revealed, suggesting a probable vaccine origin for this strain. Translational benefit of the newly developed protocol was immediately achieved by sequencing a H7N7 high pathogenic avian influenza virus, which caused disease in humans. The genetic diversity of SIVs demonstrated in our investigation confirms the importance of continuous monitoring of SIV genomic constellation.

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