54 research outputs found
Mycobacterium caprae in a dairy farm in northeast italy
No full textCon Decisione 2008/404/CE, la Regione Veneto è stata dichiarata Ufficialmente Indenne (UI) da tubercolosi bovina ai sensi della Direttiva 64/432/CEE. A settembre 2015 è stato identificato un focolaio di tubercolosi bovina in un allevamento di 69 bovini da latte
della provincia di Padova. Sottoposti a controlli ufficiali, 24 di essi (34.78%) hanno reagito positivamente alla prova intradermica. Mycobacterium caprae è stato isolato in campioni appartenenti a 22 capi e identificato attraverso tecniche biomolecolari. Le PCR utilizzate hanno rilevato la presenza del sottotipo Allgäu, e non è stata riscontrata nessuna variazione tra i diversi isolati. L’indagine epidemiologica ha evidenziato che 16 bovine erano state introdotte dall’Austria tra la fine del 2011 e l’inizio del 2015. Tuttavia le analisi biomolecolari hanno evidenziato una stretta correlazione tra il M. caprae isolato in questo studio e il ceppo identificato negli anni 2007-2009 nella Provincia di Trento, sebbene nessun contatto a rischio sia stato individuato. Il M. caprae è un agente zoonotico che rappresenta un grave pericolo per la salute pubblica e risulta indispensabile che i piani di controllo si basino su un’attenta
valutazione del rischio di possibile introduzione anche nei territori dichiarati ufficialmente indenni da tubercolosi bovina .Veneto region, Northeast Italy, has been declared officially free from bovine tuberculosis since 2008, although the disease is sporadically detected in association with cattle trade. In September 2015, bovine tuberculosis was detected in a dairy cattle farm of the region, in a holding with 69 animals. The herd underwent single intradermal tuberculin testing as part of the regional surveillance plan, and 24 animals resulted positive. Mycobacterium caprae was evidenced in 22 samples, further genotyped by PCR-based assays as Allgäu type. Epidemiological investigation reported that sixteen animals were introduced from an officially tuberculosis free Member State in previous years. Nevertheless, spoligotyping and multilocus variable tandem repeat analysis (MLVA) indicated that M. caprae was strictly related to the strain circulating in 2007-2009 in Trento province (Trentino-Alto Adige region, Northeast Italy), although no at-risk contacts were described. M. caprae is a zoonotic pathogen and further analyses are warranted in order to control its spread and impact on public health and animal trade
Rilievo del virus della rinotracheite infettiva del bovino (IBR) mediante sonde di acidi nucleici
No full textLeptospira interrogans serovar sejroe infection in a group of laboratory dogs
No full textInterstitial nephritis was seen histologically in 19 (59%) out of 32 pure-breed beagle dogs (16 males and 16 females) subjected to standard safety tests. In these animals no clinical abnormalities were observed and all the tested parameters (haematology, biochemistry and urine analysis) were within the normal ranges. Leptospiral antibody titres ranging from 1:100 to 1:6400, against a serovar (hardjo) belonging to the Sejroe serogroup, were detected by the microscopic agglutination test (MAT) in the serum of the 19 dogs with interstitial nephritis. All animals without renal lesions were seronegative. Leptospiral antigen was detected immunohistochemically in the kidneys of 4 dogs; leptospires were detected in Warthin-Starry stained sections of one dog. Leptospires were isolated from the kidneys of 3 of the 4 dogs examined by bacterial culture. The isolated strains were typed as serovar sejroe by restriction endonuclease digestion and Southern blot hybridization analysis of their DNA. It was concluded that Leptospira interrogans serovar sejroe, was responsible for an asymptomatic chronic renal infection which was widespread in this group of laboratory dogs
Detection of bovine herpes virus I (BHV-I) semen infections by a dot-blot hybridization assay
No full textDiscontinuous Galerkin Reduced Basis Element methods for parametrized partial differential equations in partitioned domains
No full textIn questa tesi si propone e si analizza un nuovo metodo discontinuous reduced basis element adatto per l'approssimazione di equazioni alle derivate parziali definite su domini partizionati.
Il metodo è suddiviso in due fasi computazionali: una fase "offline" ed una fase "online". Nella fase offline, uno spazio ridotto globale (discontinuo) non-conforme è costruito come somma diretta di funzioni di base locali, generate indipendentemente su ciascun sottodominio.
E' importante sottolineare che per generare le basi locali vengono risolti solo problemi locali.
Nella fase online, dato un valore del parametro, la soluzione approssimata è ottenuta imponendo (debolmente) le proprietà di continuità della soluzione attraverso le interfacce con un approccio di tipo discontinuous Galerkin. Per questa ragione ci si riferirà al metodo come "metodo discontinuous Galerkin Reduced Basis Element" (DGRBE).
Il metodo DGRBE è dapprima presentato in un contesto astratto, in modo da renderlo applicabile ad una vasta classe di problemi. In questa tesi ci si occupa principalmente di problemi ellittici e di Stokes.
Oltre all'introduzione del metodo e degli algoritmi usati per costruire le basi locali, si effettua anche una dettagliata analisi teorica, nella quale sono indagate le proprietà di stabilità e di approssimazione del metodo.
Inoltre viene proposto uno stimatore a posteriori dell'errore, nel caso di problemi ellittici, che consente di stimare l'errore di approssimazione commesso dal metodo DGRBE rispetto ad una approssimazione high-fidelity. I risultati esposti sono accompagnati e verificati da numerosi esperimenti numerici.In this thesis, a new discontinuous reduced basis element method suitable for the approximation of parametrized elliptic PDEs in partitioned domains is proposed and analysed.
The method is built upon an offline stage (parameter independent) and an online (parameter dependent) one. In the offline stage a non-conforming (discontinuous) global reduced space is built as a direct sum of local basis functions generated independently on each subdomain.
However, only local problems are solved to generate the basis functions.
In the online stage, for any given value of the parameter, the approximate solution is obtained by (weakly) ensuring the continuity properties of the solution across interfaces thanks to a discontinuous Galerkin approach. For this reason, the method is referred to as discontinuous Galerkin Reduced Basis Element method (DGRBE).
At first, the DGRBE method is presented in an abstract setting, by which it becomes effectively applicable to a wide class of differential problems. The focus is in particular on elliptic and Stokes equations.
Besides the introduction of the method and the algorithm used to build the local bases, a detailed theoretical analysis is carried out, in which the stability and the approximation properties of the global reduced space are investigated. An \textit{a posteriori} error estimation strategy is also developed, in the case of elliptic problem, which allow to estimate the error committed by the DGRBE approximation with respect to a high-fidelity approximation. Finally, several numerical experiments are performed to assess the performance of the DGRBE method.DIPARTIMENTO DI MATEMATICA28LUCCHETTI, ROBERTOSABADINI, IRENE MARI
Mycobacterium bovis isolates from humans: genetic profiles comparison with genotype database of animal tuberculosis strains isolated in Italy from 2000 to 2012
No full textSpoligotyping and Variable Number Tandem Repeats (VNTR) analysis of M. bovis and Mycobacterium caprae strains isolated during the national eradication programme of bovine tuberculosis (bTB) in Italy, has been routinely performed since 2000. VNTR typing includes 5 ETRs and 7 QUBs/MIRU markers (QUB11a, QUB11b, QUB26, QUB1895, QUB15, QUB3232, MIRU26) selected for their high genotypic discriminatory power.
This has enabled to obtain a national animal database (ITAN-TB) containing information and genotypes of 4291 M. bovis/M. caprae strains isolated from 2500 TB outbreaks as a supporting tool for epidemiological tracing of TB.
In this study a collection of 141 M. bovis and 2 Mycobacterium caprae recovered from human patients in Lombardy, Tuscany, Piedmont and Emilia-Romagna, from 2000 to 2012, were characterized by the same genotyping method. We identified 45 spoligotypes, 9 of which (involving 12 strains) never described in the international website www.M.bovis.org and 14 (involving 17 strains) not reported in the animal database. The remaining 22 spoligotypes, representing 114 out of the 143 human strains, were already present in the ITAN-TB.
The most frequent spoligotypes were SB0120, SB0134 and SB0841 found respectively in 41%, 7,9% and 5,9% of the human isolates and described as prevalent also in M. bovis population of animal origin (53,6%, 8,9% and 6,2%).
Combination of the 22 spoligotypes present in the ITAN-TB, with VNTR analysis discriminated the 114 strains into 46 different genotypes, 31 of which unique in humans (differ by at least 2 VNTR markers compared to animal genotypes) and 15 identical or almost identical (single locus variation) to genotypes described in TB positive cattle/buffalo herds localized mainly in Southern Italy. In particular two genotypes were widespread both in human patients than in animal database: SB0134-ETR54534-VNTR 10, 4, 5, 4. 3, 5/6, 5 and SB120-ETR45533-VNTR 10, 4, 4, 4, 3, 6, 5/6 (order of markers as described above), found respectively in 4 and 6 patients and in 42 and 97 TB outbreaks.
Interestingly most of M. bovis human isolates which showed a correspondence with animal genotype database were recovered from Italian-born patients
Sterol Biomarker Discovery In Neurodegenerative Diseases
No full textNeurodegenerative diseases (ND) are age-related heterogeneous disorders leading to uncontrollable neuroneal cell death. Nowadays, there is no cure or specific diagnostic biomarkers for ND. However, much evidence links disrupted brain cholesterol metabolism with the development of Alzheimer’s (AD) and Parkinson’s (PD) diseases, the two most common ND. Cholesterol is the most abundant sterol lipid in the human brain, the main component of myelin and a modulator of many neuroneal pivotal pathways. Several attempts have been made to understand the role and the entity of the sterol variations over PD and AD, highlighting modifications in the plasma and CSF content of the main brain cholesterol metabolite (24S)-hydroxycholesterol, (24S)-HC, and cholesterol itself but no conclusive results are yet reported. This thesis has been designed to study the plasma and CSF cholesterol and cholesterol metabolite variations in AD and PD, evaluating the ability of the discriminating sterols to be putative biomarkers. Our findings report a complete sterolome profile for AD CSF and PD plasma/CSF, identifying up to 21 different sterols. The results show an increase in the plasma levels of (24S)-HC and of 7α-hydroxy-3-ketone-cholestenoic acids in PD patients with respect to healthy controls. A decrease in plasma cholesterol is also observed in the PD group. However, (24S)-HC is the only sterol to also discriminate between males and females affected by PD and to demonstrate a diagnostic ability to predict PD. CSF and plasma sterols have also been screened in progressive PD, resulting in no significant variation, making them unsuitable prognostic biomarkers. In AD CSF, a positive correlation between the level of extracerebral 26-hydroxycholesterol, (24S)-HC and disease severity is reported. In conclusion, the results reported in this thesis support the use of cholesterol metabolites as diagnostic biomarkers for ND. However, validation studies on different cohorts of patients are needed
Persistent replication of severe acute respiratory syndrome coronavirus in human tubular kidney cells selects for adaptive mutations in the membrane protein.
No full textSevere acute respiratory syndrome (SARS) is a systemic disease characterized by both lung pathology and widespread extrapulmonary virus dissemination causing multiple organ injuries. In this regard, renal dysfunction is an ominous sign in patients with SARS. Indeed, clusters of SARS coronavirus (SARS-CoV) particles have been detected in the cytoplasm of renal tubular epithelial cells in postmortem studies, explaining the presence of infectious virus in the urine of SARS patients. In order to investigate the potential SARS-CoV kidney tropism, we have evaluated the susceptibility of human renal cells of tubular and glomerular origin to in vitro SARS-CoV infection. Immortalized cultures of differentiated proximal tubular epithelial cells (PTEC), glomerular mesangial cells (MC), and glomerular epithelial cells (podocytes) were found to express the SARS-CoV receptor angiotensin-converting enzyme 2 on their surface. Productive infection, however, occurred only in PTEC but not in glomerular cells. A transient infection with poor virus production was observed in MC, whereas podocytes were not permissive to SARS-CoV infection. In contrast to the cytopathic infection of the Vero E6 cell line, SARS-CoV did not cause overt cytopathic effects in PTEC or MC. Of interest, PTEC, but not MC, maintained stable levels of SARS-CoV production in serial subcultures, suggesting a persistent state of infection. In this regard, a SARS-CoV variant with increased replication capacity in PTEC was selected after four serial subculture passages. This SARS-CoV variant acquired a single nonconservative amino acid change from glutamic acid (E) to alanine (A) at position 11 in the viral membrane (M) protein. The E11A point mutation was sufficient for enhanced SARS-CoV replication and persistence in PTEC when introduced in a SARS-CoV recombinant infectious clone. These findings indicate that human PTEC may represent a site of SARS-CoV productive and persistent replication favoring the emergence of viral variants with increased replication capacity, at least in these kidney cells
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