Дисертації з теми "Mycobacterium avium subsp. paratublerculosis"
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Bono, Marc Enrico. "Ein Beitrag zur lebensmittelhygienischen Bedeutung von Mycobacterium avium subsp. avium /." [S.l.] : [s.n.], 1994. http://www.ub.unibe.ch/content/bibliotheken_sammlungen/sondersammlungen/dissen_bestellformular/index_ger.html.
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Schulze, Martina. "Untersuchungen zur Stammdifferenzierung von Mycobacterium avium subsp. paratuberculosis /." Berlin : Mbv, Mensch-und-Buch-Verl, 2009. http://d-nb.info/995894671/04.
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Turenne, Christine. "The evolution of the pathogen «Mycobacterium avium» subsp «paratuberculosis»." Thesis, McGill University, 2009. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=32284.
Повний текст джерелаАнотація:
The genus Mycobacterium is best recognized for its pathogens M. tuberculosis and M. leprae, the etiologic agents of Tuberculosis and Leprosy. Sequencing of their genomes has revealed an evolutionary process of reductive genomics. Another common species, the M. avium complex (MAC), consists of both environmental isolates that can cause opportunistic infection in humans as well as pathogenic isolates that cause disease primarily in birds and livestock. The basis of this variation in disease phenotypes is unknown. Two genome sequences representing a pathogen of cattle, M. avium subsp. paratuberculosis (MAP) and an opportunistic isolate from a human (M. avium subsp. hominissuis) have served as the foundation for the comparative genomics of MAC. This is complicated by a level of genetic variability one log greater than found within the M. tuberculosis complex (MTBC), and by the existence of other MAC subsets beyond the two sequenced strains. In this thesis, I set out to define the phylogenetic relationships of the various members of MAC and explore the evolutionary processes that led to the emergence of the pathogenic species MAP. An identification scheme was developed to unambiguously brand subsets of MAC, a tool lacking in the past thus hampering data interpretation. Expansion to a multilocus sequence analysis (MLSA) system revealed that the MAC consists of a highly variable group with most of the genotypes belonging to what is considered to be the environmental subset. However, both the avian and MAP pathogens manifested as two separate clones that have independently evolved from their larger subset. The distribution and directionality (insertion or deletion) of large seLe genre Mycobacterium est mieux reconnu pour ses espèces pathogènes M. tuberculosis et M. leprae, les agents étiologiques de la tuberculose et de la lèpre. Le séquençage de leur génome a indiqué un processus évolutionnaire de réduction génomique. Des autres espèces communes, le complexe M. avium (MAC) est composé de souches environnementales qui peuvent causer des infections opportunistes chez l'homme aussi bien que de souches pathogènes qui causent la maladie principalement chez les oiseaux et le bétail. La base de cette variation phénotypique est inconnue. Deux séquences génomiques représentant le pathogène de bétail M. avium subsp. paratuberculosis (MAP) et un isolat opportuniste d'humain (M. avium subsp. hominissuis) ont servi de base pour la génomique comparative du MAC. Ceci est compliqué par un niveau de variabilité génétique d'un ordre logarithmique plus grand que celui qui se trouve dans le complexe de M. tuberculosis (MTBC), et par l'existence d'autres sous-ensembles de MAC au-delà des deux souches séquençées. Dans cette thèse, je cherche à définir les rapports phylogénétiques des divers membres du MAC et à explorer les processus évolutionnaires qui ont mené à l'apparition de l'espèce pathogène MAP. Une technique d'identification a été développée pour déterminer clairement les sous-ensembles de MAC, un outil dont l'absence par le passé limitait l'analyse des données. La possibilité d'utiliser un système d'analyse par séquençage multi-locus (MLSA) a révélé que le MAC est composé d'un groupe hautement variable avec la plus grande partie des génotypes appartenant à ce que l'on considère comme étant le$
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Mathie, Heather. "Early macrophage response to Mycobacterium avium subspecies paratuberculosis." Thesis, University of Edinburgh, 2018. http://hdl.handle.net/1842/31378.
Повний текст джерелаАнотація:
Mycobacterium avium subsp. paratuberculosis (MAP) is the causative agent of Johne's disease, a chronic enteritis that has a damaging economic and welfare impact on the livestock industry. Johne's disease in cattle is known to reduce milk yield and carcass value, making it of economic concern to both dairy and beef farmers. In addition, there is cause for concern regarding zoonotic transmission, as there is an unconfirmed but potential relationship between MAP infection and human Crohn's disease, which presents similar clinical symptoms. MAP is most often contracted by neonates through the faecal-oral route, but can also be spread through contact with contaminated milk and colostrum, as well as in utero. Once the host receives an oral dose, the bacteria traverse the gut epithelium and are phagocytosed by gut macrophages residing in the lamina propria and Peyer's patches. MAP are able to evade the macrophage response by resisting intracellular degradation within phagosomes. Infected macrophages respond to the infection by secreting several pro-inflammatory cytokines that drive the downstream immune response and granuloma formation. This work aimed to elucidate key early responses of bovine monocyte derived macrophages (MDM) to MAP infection, and determine the reliability of using the reference strain, K10 (which is likely to have undergone lab adaptation) to model the infection in vitro, by comparing the MDM response to K10 with the response to a recent clinical isolate, C49. At a multiplicity of infection of 5 (MOI 5), there was a significant decrease in K10 intracellular survival (~90%), compared to C49 intracellular survival, over a 24 hour infection time-course. This suggests that K10 may have lost some virulence mechanism through lab adaptation. Understanding the mechanisms of how MDM respond to these two strains could be informative for the design of targeted vaccines When further investigating the MDM response to both strains, it was found that, at MOI 5, MDM infected with K10 secreted higher levels of IL-1β and IL-10, compared to MDM infected with C49. Both cytokines are associated with mycobacterial infection and could perhaps indicate that MDM are more responsive to the K10 strain at early time-points. In addition, MDM infected with K10 produced significantly higher levels of reactive nitrogen species (RNS). RNS are antimicrobial products that can destroy invading pathogens, and have been shown to have bactericidal effects on MAP. The production of RNS could, therefore be a potential mechanism by which MDM are able to kill K10 more efficiently than C49. An additional aim of this project was to understand the importance of the route of phagocytosis in determining the outcome of MAP infection. MDM express several phagocytic receptors, including Fc receptors (FcRs), complement receptors (CR), Ctype lectin receptors and scavenger receptors. This project mainly focused on the role of the mannose receptor (MR) on bacterial uptake and downstream immune responses, as past studies have suggested that other species of mycobacteria such as M. tuberculosis, target the mannose receptor in order to regulate macrophage immune responses. Blocking the MR reduced intracellular survival for both strains of MAP; however, the mechanism by which the MR influences intracellular survival remains poorly understood The effect of opsonisation on MAP prior to uptake by phagocytic cells was also investigated, as presence of opsonins, such a complement proteins and antibody, can change the mechanism by which pathogens are phagocytosed. MAP were incubated in serum from either MAP- negative or MAP- positive cattle, prior to infection and the percentage uptake and survival assessed by performing colony counts. Opsonisation in serum from Johne's negative cattle resulted in marked increase in MAP uptake but not intracellular survival, whereas opsonisation in serum from Johne's positive cattle did not increase uptake but decreased the intracellular survival rate by 24 HPI. This finding highlights a potential protective role of antibody early in the infection process, and could significantly impact how the infection is modelled in future, as anti-MAP antibody may be present in contaminated milk at the point of infection. Taken together, the data presented in this thesis show that bacterial strain has a significant impact on MDM response to MAP infection, which may have important implications for the interpretation of previous studies and the design of future studies investigating host-pathogen interactions in the context of paratuberculosis. Additionally, this work has shown that RNS production and the mechanism of uptake can affect intracellular survival rates, and although this needs further investigation, the findings could have implications for the design of future vaccines.
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Schulze, Martina [Verfasser]. "Untersuchungen zur Stammdifferenzierung von Mycobacterium avium subsp. paratuberculosis / Martina Schulze." Berlin : Freie Universität Berlin, 2009. http://d-nb.info/102370840X/34.
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Lahiri, Annesha [Verfasser]. "The genetic diversity of Mycobacterium avium subsp. hominissuis / Annesha Lahiri." Berlin : Freie Universität Berlin, 2014. http://d-nb.info/1051812402/34.
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Martinho, António Pedro Alegre. "Rastreio de mycobacterium avium subsp. paratuberculosis na doença de Crohn." Master's thesis, [s.n.], 2012. http://hdl.handle.net/10284/3571.
Повний текст джерелаАнотація:
Trabalho apresentado à Universidade Fernando Pessoa como parte dos requisitos para obtenção do grau de Mestre em Ciências FarmacêuticasO possível envolvimento de Mycobacterium avium subsp. paratuberculosis (MAP) na etiologia da doença de Crohn tem gerado muita controvérsia ao longo dos anos. A utilização de métodos de identificação por PCR reportou a detecção de MAP em pacientes com doença de Crohn, mas também em indivíduos sem doença. Outros estudos reportam resultados negativos para ambos os grupos. O objectivo deste trabalho foi verificar se na população de doentes estudada se encontrava uma associação entre presença de MAP e DC. Efectuou-se detecção de MAP em 29 amostras de sangue periférico: 11 amostras de pacientes com doença de Crohn e 18 amostras de indivíduos controlos. As amostras foram analisadas por desagregação das células e extracção do DNA tendo sido, de seguida, utilizada a técnica de PCR-nested para amplificação de parte da sequência de inserção IS900, específica do MAP e presente em elevado número de cópias. A análise dos produtos amplificados foi efectuada por electroforese em gel de agarose. DNA de MAP foi detectado em 9 dos 11 pacientes (82%) e 4 dos 18 controlos (22%), o que sugere uma associação entre MAP e DC na população estudada.
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Ghadiali, Alifiya H. "Studies on Mycobacterium avium subsp. paratuberculosis genotypic and phenotypic variations /." Connect to this title online, 2005. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1110229469.
Повний текст джерелаАнотація:
Thesis (Ph. D.)--Ohio State University, 2005.Document formatted into pages; contains xxi, 216 p. Includes bibliographical references. Abstract available online via OhioLINK's ETD Center; full text release delayed at author's request until 2006 March 9.
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Gray, Patricia Lara-Lynn. "Humoral response to Mycobacterium avium subsp. avium in naturally infected ring-neck doves (Streptopelia risoria)." [College Station, Tex. : Texas A&M University, 2007. http://hdl.handle.net/1969.1/ETD-TAMU-2610.
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Herthnek, David. "Detection and confirmation of Mycobacterium avium subsp. paratuberculosis in clinical samples /." Uppsala : Dept. of Biomedical Sciences and Veterinary Public Health, Swedish University of Agricultural Sciences, 2006. http://epsilon.slu.se/10210535.pdf.
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Gutiérrez, Duprat Ximena Alejandra. "Detección de Mycobacterium avium subsp. paratuberculosis en caprinos de la Región Metropolitana." Tesis, Universidad de Chile, 2005. http://repositorio.uchile.cl/handle/2250/130864.
Повний текст джерелаАнотація:
Memoria para optar al Título
Profesional de Médico VeterinarioLa Paratuberculosis es una enfermedad infecto contagiosa crónica con un largo período de incubación causada por Mycobacterium avium subsp. paratuberculosis (MAP), que afecta principalmente a los rumiantes, generando diarrea en algunas especies, caquexia y debilitamiento progresivo y como consecuencia, perdidas económicas en los rebaños. También infecta a animales silvestres que actuarían como posibles reservorios y se le asocia un posible potencial zoonótico, habiendo sido aislada la bacteria en algunos pacientes con la Enfermedad de Crohn, siendo el posible vehículo de infección la leche, ya que esta bacteria resistiría la pasteurización. En este estudio se trata de detectar la presencia de Mycobacterium paratuberculosis desde heces de caprinos de la región Metropolitana. Se realizaron cultivos bacteriológicos para M. paratuberculosis según recomendaciones del Australian Standard Diagnostic Techniques (ASDT) y con las modificaciones que permiten una mejor eficiencia en la recuperación de la bacteria. El medio de cultivo para aislamiento primario es el medio de Herrold con yema de huevo (HEYM) más mycobactina J. Se tuvo acceso a 10 rebaños donde se seleccionaron el número de animales en múltiplos de cinco, tratando de abarcar el 25% de la población de cada rebaño. Se recolectaron muestras directamente desde el recto, tomando 1 a 2 heces de cada caprino, que se depositaron en bolsas de plástico estéril agrupándose en “pools” de cinco animales. Para tener una mayor probabilidad de detectar rebaños caprinos infectados con MAP, se consideraron hembras mayores de un año, y en lo posible animales que hayan presentado signos de diarrea, debilitamiento, pérdida de peso progresiva, disminución de la producción láctea, etc. Se comprobó la presencia de MAP desde heces de caprinos de la Región Metropolitana en 3 rebaños de los 10 muestreados, encontrándose un 18% de los “pools” positivos a MAP. El medio HEYM más la adición de mycobactina J demostró claramente ser muy efectiva para el aislamiento del MAP a partir de muestras de heces de animales que ya estaban diseminando el microorganismo
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Herthnek, David. "Molecular diagnostic methods for Mycobacterium avium subsp. paratuberculosis : more than a gut feeling /." Uppsala : Department of Biomedical Sciences and Veterinary Public Health, Swedish University of Agricultural Sciences, 2009. http://epsilon.slu.se/200920.pdf.
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Moolji, Jalaluddin. "Transposon mutagenesis of «Mycobacterium avium» subsp. «paratuberculosis» to investigate potential pathogenicity islands." Thesis, McGill University, 2010. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=95051.
Повний текст джерелаАнотація:
Mycobacterium avium subsp. paratuberculosis (MAP) is the causative agent of Johne's disease, a highly prevalent chronic intestinal disease of cattle. It is also the putative cause of Crohn's disease, a chronic inflammatory bowel disease of humans. The MAP genome contains six segments of DNA called large sequence polymorphisms (LSPP) that are not present in its closest evolutionary relatives and were probably acquired through horizontal gene transfer. Together, they comprise 125kb, or 2.5% of the MAP genome, and contain 96 open reading frames. A detailed analysis of MAP evolution led us to hypothesize that the LSPP are pathogenicity islands, encoding genes important for MAP survival or replication in the host. To test this hypothesis, we generated a 5,000-member transposon-mutant library in MAP K-10 and developed a PCR screening method to identify potential mutants of LSPP genes. We succeeded in isolating a mutant of MAP3776c, which encodes a putative zinc siderophore. It is part of a putative five-gene zinc uptake operon that occupies almost the entirety of the insertion sequence, LSPP15. The MAP3776c mutant does not appear to have in vitro growth defects, and it is able to colonize the livers and spleens of C57Bl/6 mice within one week of intraperitoneal infection. Upcoming data from an ongoing, long-term experiment will determine whether the mutant has altered ability to persist in mice. The mutant of MAP3776c and the transposon-mutant library are useful tools for research on MAP genomics and pathogenicity that might ultimately contribute to improvements in vaccines and immunodiagnostics for Johne's disease.Titre de la thèse : La Mutagénèse de Transposon de Mycobacterium avium sous-espèce paratuberculosis pour Investiguer des Zones de Pathogenicité Potentielles. Résumé : Mycobacterium avium sous-espèce paratuberculosis (MAP) est l'agent causal de la maladie de Johne, une maladie chronique intestinale des bétails très répandue. C'est aussi l'agent causal putatif de la maladie de Crohn, une maladie inflammatoire de l'intestin chronique chez l'humain. Le génome de MAP contient six segments d'ADN appelés des grands polymorphismes de séquences (LSPP) qui ne sont pas présents chez les cousins évolutionnaires de cette bactérie et qui furent probablement obtenus par transfert génique horizontal. Ensembles, ils constituent 125kb soit 2,5% du génome de MAP, et contiennent 96 cadres de lecture ouverts. Une analyse approfondie de l'évolution de MAP nous a mené à supposer que les LSPP sont des zones de pathogenicité qui codent des gènes importants pour la survie et la réplication de MAP dans l'hôte. Afin de tester cette hypothèse, nous avons produit une banque de mutants de transposon de MAP de 5 000 membres, et nous avons mis au point des conditions de réaction en chaîne par polymérase (PCR) pour identifier des mutants potentiels des gènes LSPP. Nous avons réussi à isoler un mutant de MAP3776c, qui encode un sidérophore de zinc. Ce dernier fait partie d'un opéron de cinq gènes pour un système de captation zinc qui prend presque la totalité de la séquence d'insertion LSPP15. Le mutant ne semble pas avoir de défauts de croissance in vitro, et il est capable de coloniser les foies et les rates des souris C57Bl/6 en une semaine à la suite d'une infection intrapéritonéalle. Les données d'expériences en cours à long terme détermineront si le mutant a une capacité modifiée à persister dans les souris. Le mutant de MAP3776c et la banque de mutants de transposon sont des outils avantageux pour la recherche sur la génomique e
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Heaslip, Darragh G. "Studies on a 34kDa protein of M. avium subsp. paratuberculosis, a putative virulence factor." Thesis, University of Surrey, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.247997.
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Marcé, Clara. "Modelling the transmission of and effectiveness of control measures for Mycobacterium avium subsp. Paratuberculosis in dairy herds." Rennes 1, 2010. http://www.theses.fr/2010REN1S047.
Повний текст джерелаАнотація:
Paratuberculosis is a worldwide incurable disease of ruminants resulting in a decrease in milk production and slaughter value. The aim of this thesis was to evaluate the epidemiological and economic effectiveness of selected control programmes in infected dairy herds. A stochastic simulation model has been developed to represent both the population dynamics within a dairy herd and the transmission of Mycobacterium avium subsp. Paratuberculosis (Map). It has been coupled to an existing bioeconomic model. The spontaneous within-herd progression of Map infection after the introduction of one infected cattle in an initially susceptible herd was studied in the absence of control measure. The effect of within-herd contacts on Map spread in a persistently infected herd was investigated. The cost-effectiveness of test-and-cull strategies to control Map infection in dairy herds was assessed. Simulation outcomes put forward that, even when no control measure is implemented, fadeout can occur if less than two clinically affected animals are present. In persistently infected herds, the two main transmission routes are transmission via the environment of the farm and in utero transmission. Isolating calves from their herd mates during the first weeks of age has no significant impact on Map transmission. Limiting or delaying calf exposure to adult faeces and early culling of clinically affected adults are thus recommended to decrease Map prevalence in infected dairy herds. Systematic test-and-cull appears cost-effective if implemented from the day one infected cattle is introduced. The tool designed here is flexible and enables studying other control options within a dairy herdLa paratuberculose est une maladie incurable des ruminants entraînant une diminution de la production laitière et de la valeur de carcasse des animaux infectés. L'objectif de ma thèse est d'évaluer l'efficacité épidémiologique et économique d'actions de maîtrise en troupeaux bovins laitiers infectés. Un modèle de simulation stochastique représentant la dynamique de population d'un troupeau bovin laitier et la transmission indirecte de Mycobacterium avium subsp. Paratuberculosis (Map) a été, élaboré puis couplé à un simulateur bioéconomique existant. L'évolution spontanée de l'infection après I'introduction d'un animal infecté dans un troupeau initialement sensible est étudiée en l'absence d'action de maîtrise. L'effet de la structure de contact sur la transmission de Map est exploré. La rentabilité de stratégies de maîtrise de l'infection est évaluée. Une extinction de l'infection peut survenir lorsque moins de deux animaux cliniquement infectés sont présents en cinq ans, en l'absence d'action de maîtrise. Dans les troupeaux infectés persistants, la transmission in utero et via l'environnement contaminé sont les deux principales voies de transmission. Empêcher le contact précoce entre veaux n'a pas d'impact sur la transmission de Map. Il est recommandé de limiter ou retarder l'exposition des veaux aux fèces des adultes et de réformer rapidement les animaux cliniquement infectés pour réduire la prévalence de l'infection. L'utilisation de tests suivis de réformes mis en place systématiquement dès l'introduction d'un animal infecté semble rentable. L'outil développé ici est flexible et permettra d'étudier d'autres actions de maîtrise en troupeau laitier
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Gollnick, Nicole Severine. "Survival of different Mycobacterium avium subsp. paratuberculosis strains in bovine monocyte-derived macrophages." Diss., lmu, 2008. http://nbn-resolving.de/urn:nbn:de:bvb:19-86923.
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Weigoldt, Mathias [Verfasser]. "Antigen expression and metabolism of Mycobacterium avium subsp. paratuberculosis in vivo / Mathias Weigoldt." Hannover : Bibliothek der Tierärztlichen Hochschule Hannover, 2012. http://d-nb.info/1036626369/34.
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O'Brien, Lorna. "Novel detection methods for Mycobacterium avium subsp. paratuberculosis : development, optimisation and field validation." Thesis, Queen's University Belfast, 2016. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.709844.
Повний текст джерелаАнотація:
Mycobacterium avium subsp. paratuberculosis (MAP) is the causative agent of Johne’s disease, a wasting disease that largely affects domestic ruminants such as cattle, sheep and goats. Clinical disease can take up to 5 years to manifest, and therefore identification of subclinically-infected animals (i.e. those which are MAP-infected but are without symptoms) is challenging. Current diagnostic approaches lack detection sensitivity and speed of acquisition of results, so there is an urgent need for the development of a rapid test, which is highly specific and highly sensitive for the detection of viable MAP in naturally-contaminated samples. The peptide-mediated magnetic separation (PMS) phage amplification assay may represent such a test as it allows for the detection of viable MAP cells within 72 hours and has an analytical sensitivity and specificity of >85% and >99%, respectively (Foddai et al., 2010). The primary objective of this research project was to optimise the PMS-phage assay further, through the generation and evaluation of novel MAP binders. Two different MS protocols were successfully developed: (1) a new PMS assay and (2) an immuno-magnetic separation (IMS) assay. Subsequently, the diagnostic potential of each of these MS protocols was evaluated, with the PMS assay successfully combined with a PCR endpoint detection method and the IMS successfully combined with both culture and phage amplification assays for the detection of viable MAP. In order to assess the diagnostic performance of the MS-based assays for the detection of viable MAP from naturally-contaminated bovine milk samples, MS-culture and MS-phage assays were employed. The results generated were compared with those of current diagnostic approaches (faecal culture and serum ELISA). Additionally, an attempt was made to characterise the binding sites of the two novel monoclonal antibodies and the peptide binder by mimotope and computational analysis. Furthermore, an alternative diagnostic application for the novel MAP-specific binders was explored through early-stage experiments to develop a lateral flow immunochromatographic assay for the detection of whole MAP cells.
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Sanchini, Andrea [Verfasser]. "Mycobacterium avium subsp. hominissuis: The importance of genetic and metabolic diversity / Andrea Sanchini." Berlin : Freie Universität Berlin, 2017. http://d-nb.info/1138234443/34.
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Walter, Gudrun [Verfasser]. "Differenzielle Zytokinantwort bei Ziegen nach experimenteller Infektion mit Mycobacterium avium subsp. paratuberculosis / Gudrun Walter." Gießen : Universitätsbibliothek, 2017. http://d-nb.info/113856592X/34.
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Cameron, Rona Mary. "Characterisation of a putative serine protease expressed in vivo by Mycobacterium avium subsp. paratuberculosis." Thesis, University of Edinburgh, 1996. http://hdl.handle.net/1842/13292.
Повний текст джерелаАнотація:
As part of a larger study to identify genes and gene products expressed in vivo by Mycobacterium avium subsp. paratuberculosis, two immunogenic clones designated S4 (1.6 kb) and S8 (3 kb) were extracted from a λgt11 genomic expression library of M.a. paratubeculosis by screening with serum from a sheep with clinical Paratuberculosis (Johne's disease). The clones were shown by antibody elution and DNA sequencing to contain fragments of the same 1.1 kb open reading frame (ORF), which encoded a native protein of approximately 34 kDa in M.a. paratuberculosis. The ORF also encoded a possible signal peptide from amino acids 1-39, suggesting the native protein is secretory. Database searches using the deduced amino acid sequence of the ORF identified a motif 'GDSGG' which displayed 100% homology to the residues surrounding the active serine in a trypsin-like serine protease. An overall homology of approximately 30% was detected with the HtrA proteins of Escherichia coli, Salmonella typhimurium, Bruncella abortus, Rochalimea henselae, and Campylobacter jejuni, which are also thought to be serine proteases. The S8 DNA insert contained the entire 1.1 kb ORF, but due to the presence of the signal peptide, the recombinant could not be expressed as a fusion protein. However the insert was successfully expressed as a free protein by translational coupling, and was found to be secreted into the E. coli periplasm, confirming the presence of a signal sequence. When several species of mycobacteria were screened with the 1.1. kb ORF only members of the M. avium complex (M. avium, M.a. paratuberculosis, M.a. silvaticum, M. intracellulare and M. scrofulaceum were found to contain the gene, although M. malmoense and M. marinum reacted weakly and may therefore contain homologous genes. The native 34 kDa protein encoded by these clones therefore appears to be a novel secretory serine protease specific to the M. avium complex of mycobacteria. However, no proteolytic activity has been demonstrated by either native or recombinant proteins.
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Okafor, Chika Chukwunonso. "Detection of Mycobacterium avium subsp. paratuberculosis IgG by a conductometric biosensor an aid in diagnosis of Johne's disease /." Diss., Connect to online resource - MSU authorized users, 2008.
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Schillinger, Simone [Verfasser]. "Durchflusszytometrischer Nachweis von Mycobacterium avium subsp. paratuberculosis-spezifischen Antikörpern im Blut von Rindern / Simone Schillinger." Gießen : Universitätsbibliothek, 2013. http://d-nb.info/1064991149/34.
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Englund, Stina. "Molecular biology techniques as a tool for detection and characterisation of Mycobacterium avium subsp. paratuberculosis /." Uppsala : Dept. of Veterinary Microbiology, Swedish Univ. of Agricultural Sciences ([Institutionen för veterinärmedicinsk mikrobiologi], Sveriges lantbruksuniv.), 2002. http://epsilon.slu.se/avh/2002/91-576-6366-1.pdf.
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Mayer, Ricarda [Verfasser], and Christina [Akademischer Betreuer] Hölzel. "Molekularbiologischer Nachweis von Mycobacterium avium subsp. paratuberculosis mit Fokus auf Milchproben / Ricarda Mayer ; Betreuer: Christina Hölzel." München : Universitätsbibliothek der Ludwig-Maximilians-Universität, 2018. http://d-nb.info/1167160525/34.
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Naugle, Alecia Larew. "Epidemiologic investigations of mycobacterium avium subspecies paratuberculosis infections in Ohio dairy herds." The Ohio State University, 2003. http://rave.ohiolink.edu/etdc/view?acc_num=osu1054053574.
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Yamasaki, Elise Miyuki. "Aspectos cl?nico-patol?gicos da paratuberculose em rebanho bovino leiteiro no munic?pio de Rio Claro, RJ." Universidade Federal Rural do Rio de Janeiro, 2010. https://tede.ufrrj.br/jspui/handle/tede/880.
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Previous issue date: 2010-01-21The epidemic and clinic-pathological aspects of paratuberculois in a dairy cattle herd in the Rio Claro county, southern Rio de Janeiro region, are described. In the years 2006-2009, eight adult cows presented chronic-intermittent diarrhea, chronic weight loss and normal appetite. At necropsy, the subserosal lymphatics were proeminent and dilated, mesenteric nodes were enlarged, and intestinal mucosa was corrugated, thickened and of microgranular aspect. Especially, in duodenum, was observed polipoids lesions in mucosa surface. Histopathology revealed, from the duodenum to the rectum, severe and diffuse granulomatous inflammation of the lamina propria and submucosa, broadened and distorced villi, marked dilatation of the lymphatic vessels in their apex, lymphangioectasia and granulomatous lymphangitis in the submucosa. Ziehl-Neelsen stain revealed variable amounts of acid-fast bacilli in macrophages, Langhan s giant cells and freely in the musosa and submucosa of the small intestine and colon, and in lymphnodes. Lesions in the lamina propria, particularly in the jejun and ileum, in some animals, were severe hypertrophy; polipoids lesions observed in duodenum mucosa was markedly muscularis mucosa hipertrophy , intestinals and duodenal glands hiperplasia. Mycobacterium avium subsp. paratuberulosis was isolated by bacterial cultivation of samples from feces, intestinal mucosa and milk, and identified through IS900 PCR. From 298 cows, older than three years, the percentage of reactive animals was 40%, in indirect ELISA test. The diagnosis of paratuberculosis was based on clinic-epidemiological data, sorology, bacterial isolation and IS900 PCR. After the adoption of control measures, as slaughter of sick cows and selective slaughter of soropositive animals, was observed reduction of clinical cases in the herd, from six cases to one case per year, in three years of study.
Descreve-se os aspectos epidemiol?gicos e cl?nico-patol?gicos da paratuberculose em um rebanho bovino leiteiro no munic?pio de Rio Claro, regi?o Sul-Fluminense, Rio de Janeiro. No per?odo de 2006 a 2009, oito vacas adultas da ra?a Girolanda apresentaram diarreia cr?nico-intermitente, perda de peso progressivo e apetite normal. ? necropsia observou-se vasos linf?ticos subserosos proeminentes, linfonodos mesent?ricos aumentados de volume, ?midos ao corte, serosa do intestino com aspecto anelado e cerebr?ide, mucosa espessada, pregueada e com aspecto microgranular. Em especial, no duodeno havia les?es polip?ides na supef?cie da mucosa. ? microscopia, desde o duodeno at? o intestino grosso, havia acentuada inflama??o granulomatosa difusa, marcada dilata??o dos vasos linf?ticos no ?pice das vilosidades, linfangiectasia e linfangite granulomatosa na submucosa, muscular e serosa, altera??es tamb?m vistas nos linfonodos mesent?ricos. A colora??o de Ziehl-Neelsen revelou, vari?vel quantidade de bacilos ?lcool-?cido resistentes no interior de macr?fagos, c?lulas gigantes de Langhans e livres na mucosa e submucosa do intestino delgado e grosso e em linfonodos mesent?ricos. A l?mina pr?pria da mucosa, principalmente do jejuno e ?leo de alguns animais, apresentava acentuada hipertrofia; as les?es polip?ides correspondiam ? marcada hipertrofia da muscular da mucosa, hiperplasia de gl?ndulas duodenais e intestinais. Mycobacterium avium subsp. paratuberculosis foi isolado em cultivo bacteriano a partir de amostras de fezes, raspado de mucosa intestinal e leite e identificado pela t?cnica de PCR IS900. Atrav?s da avalia??o sorol?gica semestral, foram analisadas 298 vacas, a partir de tr?s anos de idade, e observou-se cerca de 40% de animais reagentes ao teste ELISA indireto no per?odo estudado. O diagn?stico da paratuberculose foi baseado nos dados cl?nicopatol?gicos, sorologia, isolamento e identifica??o do agente em amostras de fezes, raspado de mucosa e leite, atrav?s do cultivo bacteriano e PCR IS900. Ap?s implementa??o de medidas de controle, tais como elimina??o de animais doentes, abate seletivo dos soropositivos, separa??o dos bezerros ao nascer com utiliza??o de banco de colostro, observou-se diminui??o da ocorr?ncia de casos cl?nicos no rebanho, de seis casos por ano para cerca de um caso por ano, em tr?s anos de estudo.
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Strickland, Summer J. "Effects of seasonal heat stress on the diagnosis of Mycobacterium avium subsp. paratuberculosis in Texas dairy cattle." Texas A&M University, 2004. http://hdl.handle.net/1969.1/2728.
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The validity of Johne??s disease herd status programs and on-farm disease control programs that rely on established ??cutpoints?? (e.g., S/P ratios) for ELISA serological tests such as the HerdChek?? (IDEXX Laboratories Inc., Westbrook, Maine) may be susceptible to varied seasonal test accuracy. An observed depression in the proportion of a large central Texas dairy herd classified as ??positive?? during the months of July and August led to our investigation. We hypothesized that there exists a seasonal variability in serological response to Mycobacterium avium subsp. paratuberculosis that is directly related to heat stress. We further hypothesized that a reciprocal response may occur during periods of heat stress that results in a greater risk of fecal shedding in subclinically-infected animals.
Starting in October 2002, we invoked a testing regime that included multiple testing of 720 individual adult cows over each of four seasons including spring, summer, fall, and winter. We collected serum on a cyclic, monthly basis from three random groupings of cows, and, based on the ELISA results, collected fecal samples from the 20% of cows with the highest S/P ratios. We continued to sample in this manner for the period of one year and at the end of that period, analyzed the serum en masse.
The ELISA outcome values were treated both as categorical and continuous variables (e.g., S/P ratio). The potential lagged effects of heat stress on S/P ratio, as well as the potential for a change in test result (negative to positive or vice versa) due to heat stress were assessed. The results for fecal culture were analyzed on a categorical scale and were compared to the ELISA results to explore the possibility of a reciprocal response.
In the present study, we did not observe any of the significant seasonal effects of heat stress on S/P ratios and proportion seropositive to MAP that were observed in the historical (and less valid) cross-sectional time-series data conducted in 2001. In addition, we found no evidence to support a hypothesis linking seasonal heat stress to the risk of fecal culture positivity for the causative bacterium for Johne??s disease.
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Mason, O. G. "The application of novel techniques to detect Mycobacterium avium subsp. Paratuberculosis in bovine and ovine field samples." Thesis, Queen's University Belfast, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.273251.
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Karcher, Elizabeth Leigh. "Evaluation of the host immune response to Mycobacterium avium subsp. paratuberculosis in naturally infected periparturient dairy cows." [Ames, Iowa : Iowa State University], 2007.
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Marcé, Clara L. H. "Modelling the transmission of and effectiveness of control measures for Mycobacterium avium subsp. paratuberculosis in dairy herds." Thesis, Royal Veterinary College (University of London), 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.558974.
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Kimsawatde, Gade Carolyn. "Establishment of a Long Term Cell Culture Model for Testing Anti-Infectives against Mycobacterium avium subsp. paratuberculosis." Diss., Virginia Tech, 2015. http://hdl.handle.net/10919/73329.
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Mycobacterium avium subsp. paratuberculosis (MAP) is a very slow growing bacterium that is the causative agent of Johne's disease (JD) in ruminants and has long been suggested to be associated with complications of Crohn's disease (CD) in humans. Although there is no direct evidence that MAP is the primary etiological agent for CD, most CD patients are found to have MAP in their intestinal tissues. The current control measures for JD in cattle, sheep, and goats have only been minimally effective, and there are only medications to treat the symptoms of mycobacterial infections associated with CD in humans.
Along with not being able to cure MAP infections, there is no established laboratory animal model for testing therapeutics. When mice are infected with MAP they develop systemic infection and do not mimic disease observed in ruminants. J774A.1 murine macrophages typically have a very short lifespan of about 4-6 days, however MAP infected cell cultures can survive up to about 10 days. Using a modified protocol of Estrella et al. (2011), we have been able to establish a 45-60 day long-term MAP infected J774A.1 murine macrophage cell culture model. With the addition of retinoic acid (RA), vitamin D (VD), and phorbol myristate acetate (PMA) in combination in cell culture, we were able to screen novel therapeutics before embarking on in vivo testing in animals. This is a significant step forward in Crohn's and Johne's disease treatment research. We are not only able to test various drugs against specific strains of MAP to determine susceptibility, but we are also able to test a wide variety of drugs at the same time, with relatively minimal cost.
We have evaluated the efficacy of clarithromycin, azithromycin, isoniazid, amikacin, ethambutol, ciprofloxacin, levofloxacin, rifampicin, clofazimine, as well as a combination of clarithromycin, rifampicin, and clofazimine using our MAP infected macrophage cell culture model. We were able to determine the drugs' differential ability to kill intracellular MAP in the early stages of infection, versus chronic stages of infection, and against two different strains of MAP, 43015 and 19698 that affect humans and cattle respectively. The minimal inhibitory concentration (MIC) of each drug was determined as per NCCLS protocol in vitro, and the drugs were tested at the MIC value, along with one concentration above and below the MIC in our cell culture model. The antimicrobials were found to be effective at different stages of cell culture infection and in different strains of MAP. Some drugs were more effective at early stages of MAP infection, whereas others were more effective in chronic or latent stages of infections. It is important to note that although a drug may be effective at a certain stage of infection, it may not necessarily be effective against all strains of MAP. The most promising results were seen with a combination of clarithromycin, clofazimine, and rifampicin, which was effective at all stages of infection with both strains of MAP tested. This long term cell culture model will provide researchers with important screening tools for evaluating new therapeutics before embarking on costly in vivo testing, and allow the assessment of therapeutics at different stages of MAP infection but also against an array of intracellular pathogens.Ph. D.
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Alajmi, Ahmad [Verfasser]. "Occurrence of Mycobacterium avium subsp. paratuberculosis (MAP) in bovine milk and feces samples from Northern Germany / Ahmad Alajmi." Hannover : Bibliothek der Tierärztlichen Hochschule Hannover, 2016. http://d-nb.info/1124560785/34.
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Botsaris, George. "Development and evaluation of a rapid phage-PCR assay to detect mycobacterium avium subsp. paratuberculosis in dairy products." Thesis, University of Nottingham, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.537656.
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Pietralonga, Pricila Aparecida Grasse. "Expressão de citocinas padrão Th1 e Th2 em camundongos C57BL/6 durante infecção de Mycobacterium avium subsp. paratuberculosis." Universidade Federal de Viçosa, 2012. http://locus.ufv.br/handle/123456789/5165.
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Previous issue date: 2012-09-04Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
Mycobacterium avium subspecies paratuberculosis (MAP) is the etiological agent of paratuberculosis, a disease which causes chronic granulomatous enteritis preferably in domestic and wild ruminants. It is considered a disease of economic and social impact, because of losses in livestock and importance in human health, since there is evidence of possible correlation of MAP with Crohn's disease. However, much is still unknown about the developing the pathophysiology and immunopathogenesis this disease, in the sites of infection. Thus, this study has proposed verify the response of cytokines proinflammatory and anti-inflammatory by quantitative PCR and associate the expression of these cytokines with the lesions and the presence of the agent in organs of C57BL/6 mice infected intraperitoneal with strain MAP66115-98. It was applied 250μl of inoculum at 3 x 108 UFC/ml in 20 mice, and it was applied saline phosphate buffers (PBS) in eight control species. The animals were sacrificed at 30, 60, 90 and 120 days post-inoculation. In each period were collected spleen, liver, intestine (ileum and colon) and Peyer's patches of five challenged mice and two controls. It was found in the majority an upregulation in the expression profiles of proinflammatory cytokines IL-2, IFN-, and TNF-α ү, and anti-inflammatory IL-4 and IL-10 analyzed in the organs compared to controls during period of the experiment. It was observed also negative regulations in the fourth week in spleen and colon, twelfth in the spleen, ileum and Peyer's patch and the sixteenth week in the liver, colon and ileum. Statistical differences were only observed at the eighth week after the challenge for IFN-ү in liver, in spleen for expression of IL-2 and IFN-ү and in the ileum for IL-4 and TNF-α. In the fourth week, it was possible to identify increased levels of mRNA transcripts of the cytokines studied. In the liver, ileum and colon IFN-ү showed the highest level of mRNA transcripts compared to the negative control, however at higher levels spleen were observed for IL- 10. Only eight weeks it was possible to observe a statistically significant difference for the cytokine IFN-ү in the liver and spleen samples for TNF-α and IL-4 in the ileum and IL-2 in spleen. The highest levels of mRNA transcript were observed in the liver for IFN- ү, spleen for IL-2, and in the ileum Peyer's patch for IL-4 and colon for IL-10. In the twelfth week, the major mRNA transcript levels were observed in liver for IL-10 in spleen and ileum for IL-2 in colon for TNF-α and Peyer's patch for IL-4. In the sixteenth week, the major mRNA transcript levels were observed in liver and colon for IL-10 in spleen and ileum for IFN-ү and Peyer's patch for TNF-α. The animals showed increased expression of mRNA transcripts of cytokines studied organs after challenge with MAP, although not verified gross and microscopic changes (hematoxylin and eosin staining). However it was possible to observe the presence of alcohol-acid resistant rods in two samples of Peyer's patches (Ziehl-Neelsen) and nested-PCR technique was possible to observe the presence of MAP in every organ analyzed. Thus, these results contribute to a better understanding of the expression of proinflammatory and anti-inflammatory in local infection at different post-inoculation in both organs taken as site specific as MAP intestine (colon and ileum) and Peyer's patch and organs extraintestinal, and thus find a better understanding of the immunopathogenesis of infection in the local.
Mycobacterium avium subespécie paratuberculosis (MAP) é o agente etiológico da paratuberculose, uma enfermidade que causa enterite granulomatosa crônica preferencialmente em ruminantes domésticos e silvestres. É considerada uma doença de impacto econômico e social, devido às perdas no rebanho e na saúde humana, uma vez que se têm indícios da possível relação de MAP com a doença de Crohn. Contudo, muito ainda se desconhece sobre o desenvolvimento da patofisiologia e imunopatogênese desta doença, nos locais da infecção. Desse modo, este estudo propôs verificar a resposta de citocinas pró e anti-inflamatórias por meio da técnica de PCR quantitativo e associar a expressão destas citocinas com as lesões e a presença do agente em órgãos de camundongos C57BL/6 infectados por via intraperitoneal com a cepa MAP66115-98. Em 20 camundongos foram aplicados 250μl de inóculo a 3 x 10 8 UFC/ml e, em oito controles foram aplicados PBS. Os animais foram sacrificados aos 30, 60, 90 e 120 dias pós-inoculação. Em cada período, foram coletado baço, fígado, intestino (cólon e íleo) e placas de Peyer de cinco camundongos desafiados e de dois controles. Verificou-se na maioria, uma regulação positiva nos perfis de expressões das citocinas pró-inflamatórias IL-2, IFN-ү e TNF-α, e anti-inflamatórias IL-4 e IL-10 nos órgãos analisados em relação aos controles durante o período do experimento. Observaram-se também regulações negativas na quarta semana no baço e colón, na décima segunda no baço, íleo e placa de Peyer e na décima sexta semana no fígado, colón e íleo. Diferenças estatísticas foram observadas somente na oitava semana após o desafio no fígado para IFN-ү, no baço para expressão da IL-2 e IFN-ү e no íleo para IL-4 e TNF-α. Na quarta semana, foi possível identificar aumento dos níveis de transcritos de RNAm das citocinas estudadas. No fígado, íleo e colón o IFN-ү apresentou maior nível de transcritos de RNAm em relação ao controle negativo, no entanto no baço os maiores níveis foram observados para a IL-10. Somente na oitava semana foi possível observar diferença estatística significativa para a citocina IFN-ү, em amostras do fígado e baço, para o TNF-α e IL-4 no íleo e para a IL-2 no baço. Os maiores níveis de transcrito de RNAm foram observados no fígado, para o IFN-ү , no baço para a IL-2 , no íleo e placa de Peyer para a IL-4 e no colón para a IL-10. Na décima segunda semana, os maiores níveis de transcrito de RNAm foram observados no fígado para a IL-10, no baço e íleo para a IL-2, no colón para o TNF-α e na placa de Peyer para a IL-4. Na décima sexta semana, os maiores níveis de transcrito de RNAm foram observados no fígado e colón para a IL-10, no baço e íleo para o IFN-ү e na placa de Peyer para o TNF-α. Os animais apresentaram uma maior expressão dos transcritos de RNAm das citocinas estudadas nos órgãos após o desafio com MAP, embora não tenham sido verificadas alterações macro e microscópica (coloração de Hematoxilina e Eosina). No entanto foi possível observar presença de bastonetes álcool ácido resistentes em duas amostras de placas de Peyer, (coloração de Ziehl-Neelsen) e pela técnica de nested-PCR foi possível observar a presença de MAP em todos os órgão analisados. Assim, estes resultados contribuem para a melhor compreensão da expressão de citocinas pró e anti-inflamatória nos locais da infecção em diferentes tempos pós-inoculação tanto em órgãos tidos como sitio específicos de MAP como intestino (colón e íleo) e placa de Peyer e órgãos extra-intestinais, e com isso buscar o melhor entendimento da imunopatogênese nos locais da infecção.
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SÁ, Luenda de Menezes e. "Aspectos epidemiológicos da infecção pelo Mycobacterium avium subsp. paratuberculosis em rebanhos leiteiros da microrregião de Garanhuns - Pernambuco, Brasil." Universidade Federal Rural de Pernambuco, 2012. http://www.tede2.ufrpe.br:8080/tede2/handle/tede2/6271.
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Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq
Paratuberculosis is a disease that can cause a negative impact on national livestock. In cattle cause chronic intractable diarrhea and granulomatous enteritis, these animals become listless and lose weight gradually, decreasing or ceasing milk production. It is caused by Mycobacterium avium subspecies paratuberculosis (MAP), an alcohol-acid resistant bacilli, resistant to many environments. The objective of this study makes an epidemiological investigation of MAP infections in dairy cattle the microregion of Garanhuns, Pernambuco, Brazil. For this study blood samples were collected from 408 animals from 19 herds in 15 counties of the microregion. Serologic testing was performed by indirect enzyme immunoassay (ELISA) for antibodies against the MAP. A questionnaire was applied to all properties for analysis of risk factors, and collected geographical coordinates through a GPS (Global Position System) device to perform the spatial distribution. The prevalence of MAP infection was 2.7% (11/408, I.C. 1.4 – 4.9). The number of foci was 47.4% (9/19). In logistic regression analysis was identified as a risk factor the annual rate of births over 51 calves / year (O.R. 3.8; I.C. 1.1 – 13.1). In conclusion an MAP infection is spread among the cattle’s herds of microregion Garanhuns, Pernambuco, Brazil, and control measures based or risk factors should be implemented to reduce the number of outbreaks and consequently increase the productivity of herds.
A paratuberculose é uma enfermidade que pode causar um impacto negativo para a pecuária nacional. Nos bovinos apresenta-se sob a forma de diarreia crônica intratável que causa uma enterite granulomatosa, onde os animais tornam-se apáticos e emagrecem progressivamente, diminuindo ou até mesmo cessando a produção leiteira. É causada pelo Mycobacterium avium subespécie paratuberculosis (MAP), um pequeno bacilo álcool-ácido-resistente, considerado como um dos menores do gênero, extremamente resistente a diversos ambientes. Objetivou-se com esse trabalho realizar um inquérito epidemiológico da infecção pelo MAP em bovinos leiteiros da microrregião de Garanhuns, Pernambuco, Brasil. Para esse estudo foram coletadas amostras sanguíneas de 408 animais, provenientes de 19 rebanhos localizados em 15 municípios da microrregião. O exame sorológico foi realizado por Ensaio Imunoenzimático (ELISA) indireto para detecção de anticorpos frente ao Mycobacterium avium subsp. paratuberculosis. Em todas as propriedades, um questionário investigativo foi aplicado para análise dos fatores de risco, e as coordenadas geográficas coletadas através de um aparelho de GPS (Global Position System) para realização da distribuição espacial. A prevalência da infecção pelo MAP foi de 2,7% (11/408; I.C. 1,4 – 4,9). O número de focos foi 47,4% (9/19). Na análise de regressão logística foi identificado como fator de risco a taxa anual de nascimentos superior a 51 bezerros/ano (OR 3,8; I.C. 1,1 – 13,1). Concluiu-se que a infecção pelo MAP encontra-se distribuída entre os rebanhos bovinos leiteiros da microrregião estudada e que medidas de controle baseadas nos fatores de risco devem ser implementadas com o objetivo de reduzir o número de focos e consequentemente aumentar a produtividade dos rebanhos, minimizando assim os prejuízos causados pela enfermidade aos produtores.
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Souza, Marina de Castro Campos de. "Caprinocultura leiteira comercial na região da Zona da Mata de Minas Gerais: organização da produção e ocorrência de Mycobacterium avium subsp. paratuberculosis (Map)." Universidade Federal de Viçosa, 2015. http://www.locus.ufv.br/handle/123456789/6701.
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Conselho Nacional de Desenvolvimento Científico e Tecnológico
Minas Gerais é o principal produtor de leite de cabra na região Sudeste e o terceiro principal estado do país nessa atividade. A paratuberculose é uma enfermidade intestinal crônica, causada por Mycobacterium avium subsp. paratuberculosis (Map), que acomete principalmente ruminantes e é transmitida pela ingestão de alimentos ou água contaminados por fezes de animais acometidos. O objetivo do trabalho foi identificar e caracterizar Mycobacterium avium subsp. paratuberculosis em fazendas de caprinos leiteiros da Zona da Mata de Minas Gerais. Foram estudadas dez propriedades, caracterizadas através da aplicação de um questionário com a pessoa responsável pelo manejo. Foram coletadas amostras de fezes e de leite dos 467 animais amostrados, que foram inoculadas em meio HEYM. As amostras de leite e as colônias suspeitas foram submetidas à PCR e aquelas consideradas positivas foram sequenciadas. Onze (2,36%) animais foram considerados positivos para a presença de Map, em quatro (40%) propriedades. Através das técnicas utilizadas, concluiu-se que Map está presente nas propriedades de caprinos leiteiros da Zona da Mata de Minas Gerais. Com esse estudo, foi possível analisar e caracterizar os diferentes modos de produção de leite de cabra empregados na Zona da Mata. Os produtores têm relativa instrução, mas ainda convivem com a baixa produtividade e o baixo rendimento da produção, o que leva a maioria a necessitar de outras fontes de renda. O incentivo governamental exerce papel fundamental na mudança do cenário atual da caprinocultura leiteira dessa mesorregião e, levando à estruturação da cadeia produtiva, alcança melhores resultados de produção e geração de emprego e renda no meio rural.
The participation of dairy goat in the Brazilian agricultural scenario has increased and has consolidated as profitable. Minas Gerais is the main producer of goat's milk in the Southeast and the third largest state in the country in this activity. The paratuberculosis is a chronic intestinal illness caused by Mycobacterium avium subsp. paratuberculosis (Map), which mainly affects ruminants and is transmitted by ingesting food or water contaminated by feces of affected animals. The objective was to identify and characterize Mycobacterium avium subsp. paratuberculosis in dairy goat farms in the Zona da Mata of Minas Gerais. Ten properties were studied, characterized by applying a questionnaire to the person responsible for the handling. Samples of feces and milk were collected of 467 animals studied, and inoculated in HEYM medium. Samples of milk and suspected colonies were submitted to PCR, and the samples considered positive were sequenced. Eleven (2.36%) animals were considered positive for the presence of Map, in four (40%) properties. Through the techniques used, it was concluded that Map is present in dairy goats properties of Zona da Mata of Minas Gerais. With this study, we analyzed and characterized different types of goat production used in the Zona da Mata. Producers have relative education, but still living with low productivity and low income of their production, which leads most in need of other sources of income. The government incentive plays a fundamental role in changing the current scenario of dairy goat at this region and, leading to the structuring of the production chain, achieves better results of production and generation of employment and income in rural areas.
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MARINO, ROSANNA. "La paratubercolosi bovina causata dal Mycobacterium avium subsp paratuberculosis: un modello in vitro per studiare la risposta precoce all'infezione." Doctoral thesis, Università Cattolica del Sacro Cuore, 2013. http://hdl.handle.net/10280/2052.
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La malattia di Johne o paratubercolosi è un’enterite cronica granulomatosa provocata dal Mycobacterium avium subsp paratubercolosis (MAP), che colpisce i ruminanti ed in particolare i bovini da latte ed ha un grande impatto economico a livello mondiale. Il MAP sembra anche avere un ruolo nella malattia umana di Crohn.
Tale patogeno è capace di sopravvivere molto bene all’interno dei macrofagi dell’ospite dove previene la loro attivazione, blocca l’acidificazione e la maturazione del fagosoma, e interferisce con la presentazione degli antigeni al sistema immunitario.
Al fine di analizzare la complessa interazione tra l’ospite e il patogeno, è stata valutata la risposta dopo 2h, 6h, e 24h di macrofagi derivati da monociti bovini (MDM), coltivati in vitro e infettati con il ceppo L1 di MAP utilizzando un approccio di RNA-Seq.
L’analisi statistica dei dati di sequenza ha mostrato un aumento del numero di geni differenzialmente espressi durante l’esperimento in risposta all’infezione. Inoltre i geni sottoespressi negli MDM infettati sono stati individuati solo a 24h post-infezione.
L’analisi dei pathway ha evidenziato tre network che sono associati alla risposta immunitaria e al processo infiammatorio. Inoltre lo studio dei geni sottoespressi a 24h ha mostrato il ruolo centrale del complemento e del complesso maggiore di istocompatibilità nella patogenesi della malattia.Johne’s disease (paratuberculosis) is a chronic granulomatous enteritis caused by Mycobacterium avium subsp paratubercolosis (MAP), affecting ruminants worldwide with a significant economic impact. MAP has also been speculated as a cause of human Crohn’s disease. MAP is a pathogen highly adapted for survival within host macrophages due to the organism's capacity to prevent macrophage activation, block phagosome acidification and maturation, and attenuate presentation of antigens to the immune system. The consequence is a very long silent infection and subclinical phases. To decipher the complex interaction between host and MAP, the response of in vitro bovine monocyte-derived macrophages (MDM) after 2h, 6h and 24h of infection with L1 strain of MAP was explored using RNA-Seq approach. Statistical analysis of sequence data revealed an increasing number of differentially expressed genes in MDM following infection through the three time points analysed. Furthermore down-regulated genes were only found at 24 h post-infection. Ingenuity Pathways Analysis of differentially expressed genes showed that “cell-mediated immune response” was the most significant network related to 2hpi dataset, “immune cell trafficking” for 6hpi, and “inflammatory response” for 24hpi. Finally the analysis of down-regulated genes at 24hpi confirmed the role of complement and major histocompatibility complex (MHC) in the pathogenesis of MAP in cattle.
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Freitas, Diogo André Andrade de. "Infectious etiology in inflammatory bowel disease – participation of mycobacterium avium subsp. paratuberculosis and adherent-invasive strains of escherichia coli." Bachelor's thesis, [s.n.], 2019. http://hdl.handle.net/10284/8522.
Повний текст джерелаАнотація:
Trabalho Complementar apresentado à Universidade Fernando Pessoa como parte dos requisitos para obtenção do grau de Licenciado em Ciências da NutriçãoInflammatory Bowel Disease (IBD) includes Crohn’s Disease (CD) and Ulcerative Colitis (UC), with its etiology still to be established. IBD has been suggested to be an interaction between genetic susceptible host, microbiome interactions and induction of an abnormal immune response. This study proposes to evaluate the multiple literature present and understand the possible activity of bacteria. There have been identified multiple polymorphisms in CD and UC patients, from multiple agents related with immune response. These polymorphisms also seem to be useful for the colonization of specific bacteria, like Mycobacterium avium. Paratuberculosis (MAP) and Adherent-Invasive Escherichia Coli (AIEC) that seem to be involved in the IBD etiology as a causative agent or as an opportunist pathogen of the genetic susceptibility, however this involvement is still unclear and the studies until now are ambiguous when compared with each other. Moreover, environmental factors like diet seem to be involved in the development of IBD, especially when considered the high prevalence and increase of IBD in western countries and newly westernized countries, respectively. Concluding that a western diet is a participant in the development of IBD. On the other side with the presence of plantbased diet it could be used as a therapeutic agent granting remission in IBD.
A Doença Inflamatória Intestinal (DII) inclui a Doença de Crohn(DC) e a Colite Ulcerosa(CU), estando a sua etiologia por estabelecer. DII encontra-se associada a uma interação entre hospedeiros geneticamente suscetíveis, interações do microbiota e a presença de uma resposta inflamatória exacerbada. Com este estudo pretendeu-se avaliar a literatura existente e estabelecer uma ligação entre a etiologia e a atividade de agentes microbianos. Foram identificados com maior frequência em pacientes com DC e CU, a presença um leque variado de polimorfismos, relacionados com os agentes eretores da resposta imune. Estes apresentam-se com ferramentas uteis para a colonização de bactérias como Mycobacterium avium. Paratuberculosis (MAP) e Adherent-Invasive Escherichia Coli (AIEC), que tem sido ligada à etiologia da DII como agentes causadores ou potenciais patogénios oportunistas. Contudo, a informação existente é ambígua não permitindo concluir a causalidade destes microrganismos. Adicionalmente, a o estudo de fatores ambientais com à dieta apresentam-se envolvidos no desenvolvimento da DII, especialmente quando considera a elevada prevalência e aumento da DII em “Western Countries” e em “Newly-Westernized Countires”, respetivamente. Levando a concluir que uma dieta ocidental é um fator de risco para o desenvolvimento da DII, realçando-se assim a dietas de base-vegetal como potenciais agentes terapêuticos para a remissão da DII.
N/A
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Hobmaier, Bernhard Franz [Verfasser], and Cornelia [Akademischer Betreuer] Deeg. "Charakterisierung von Pflanzenlektinen bezüglich ihrer Eignung zur Anreicherung von Mycobacterium avium subsp. paratuberculosis aus Milch / Bernhard Franz Hobmaier ; Betreuer: Cornelia Deeg." München : Universitätsbibliothek der Ludwig-Maximilians-Universität, 2020. http://d-nb.info/1206878355/34.
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Stau, Angelika [Verfasser]. "Untersuchungen zur Seroprävalenz von Mycobacterium avium subsp. paratuberculosis beim kleinen Wiederkäuer in Deutschland und zur Impfung gegen Paratuberkulose bei Milchziegen / Angelika Stau." Hannover : Bibliothek der Tierärztlichen Hochschule Hannover, 2013. http://d-nb.info/1037883470/34.
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Khattak, Faisal Asghar [Verfasser]. "An efficient method for random mutagenesis in Mycobacterium avium subsp. hominissuis and for screening of mutants affected in virulence / Faisal Asghar Khattak." Berlin : Freie Universität Berlin, 2012. http://d-nb.info/1027309585/34.
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Schwarz, David Germano Gonçalves. "Studies on the interaction between Mycobacterium avium subsp. paratuberculosis and bovine mastitis associated Escherichia coli in a mammary epithelial cell model and identification of passive shedding in small ruminants." Universidade Federal de Viçosa, 2016. http://www.locus.ufv.br/handle/123456789/9794.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
Mastite causada por Escherichia coli tem a capacidade de estimular intensamente o sistema imunológico e desencadear rapida inflamação na glândula mamária. Em contraste, Mycobacterium avium subsp. paratuberculosis (MAP), agente etiológico da paratuberculose, caracterizada por enterite granulomatosa crônica, pode infectar a glândula mamária sem estimular intensamente a resposta inflamatória. A interação dessas duas bactérias na glândula mamária ainda é desconhecida. Em alguns casos, tanto a eliminação de MAP pelo leite como pelas fezes podem ocorrer de forma passiva, após a infecção ascendente da glândula mamária ou após ingestão de MAP, respectivamente. Estes animais, chamados passive-shedders, são importantes como uma fonte de infecção a animais suscetíveis no rebanho. O objetivo deste estudo foi investigar a relação entre MAP e E. coli em células de glândula mamária sob condições experimentais e verificar a presença de animais passive-shedders. A relação entre uma cepa K-10 de MAP e E. coli isolada de leite mastítico em linhagem de células epiteliais mamárias (MAC-T) foi avaliada. As células previamente infectadas com MAP diminuíram a invasão de E. coli durante 120 min de experimentação. Contudo, a eficiência da translocação de E. coli e a viabilidade das células MAC-T não foram comprometidas. Ao contrário, células previamente infectadas por E. coli aumentaram a capacidade de translocação baso-apical de MAP até os 30 min e diminuiu aos 120min pós-infecção. A quantificação de citocinas relevou que a expressão de IL-1β aos 120min foi significativa (P<0.05) para células infectadas por MAP + E. coli e E. coli apenas. As expressões de MAPKp 38 e IL-10 não foram significativas, independente do tempo pós-infecção. Para detectar a ocorrência de animais passive-shedders, 10 propriedades foram previamente investigadas para a presença de MAP. Treze cabras foram positivas por cultura de fezes e/ou PCR de leite. Dentre os animais positivos, quatro (4/13) foram adquiridas e avaliados por IS900-PCR, cultura de fezes, de leite e de tecido, e sorologia (ELISA). Todos os resultados foram negativos no período de um ano, demonstrando que os animais realizaram o fenômeno pass-through e a contaminação ascendente da glândula mamária, sem tornarem-se infectados. No geral, esses resultados indicam que a presença de MAP nas células mamárias pode dificultar a capacidade de invasão de E. coli, mas quando no interior da célula mamária, translocam-se mais eficientemente. No entanto, quando as células são previamente infectadas por E. coli, MAP é rapidamente atraído da região subepitelial para a superfície celular. A produção de IL-1β intensifica a atração de macrófagos para o sítio de infecção, onde MAP se beneficia, infectando-os.
Mastitis caused by Escherichia coli can intensely stimulate the immune system and rapidly trigger inflammation in the mammary gland. In contrast, Mycobacterium avium subsp. paratuberculosis (MAP), the etiological agent of paratuberculosis, characterized by chronic granulomatous enteritis, can infect the mammary gland without intensely stimulating the inflammatory response. The interaction of these two species in the mammary gland is still unknown. In some cases, both the elimination of MAP by milk and faeces may occur passively, either through ascending infection of the mammary gland or through ingestion of MAP, respectively. These animals are called passive- shedders and are important as a source of infection to susceptible animals in the herd. The aim of this study was to investigate the relationship between MAP and E. coli in mammary gland cells under experimental conditions and verify the presence of passive- shedder animals. The relationship between a K-10 strain of MAP and E. coli isolated from mastitic milk in mammary epithelial cell lines was evaluated. Cells previously infected by MAP decreased E. coli invasiveness during 120min experimentation. However, the efficiency of E. coli translocation was not compromised, nor was the viability of the MAC-T cells. In contrast, cells previously infected by E. coli showed increased basal-apical translocation capacity of MAP up to 30 min and decreased at 120 min postinfection. Quantification of cytokines showed that IL-1β expression at 120 min was significantly increased in cells infected by MAP + E. coli and E. coli only. Expression of MAPKp 38 and IL-10 were not significant, regardless of time postinfection. To determine the occurrence of passive-shedders, 10 properties were previously investigated for MAP detection. Thirteen goats were positive by faeces culture and/or milk PCR. Among the positive animals, four (4/13) were evaluated by IS900-PCR, feces culture, milk and tissue culture and serology (ELISA). All the results were negative over a one-year period, demonstrating that the animals performed pass- through phenomenon and upward contamination of the mammary gland without becoming infected. Together, these results indicate that the presence of MAP in mammary cells may hamper capacity of E. coli invasion, but when within the mammary cell, the bacteria evade more efficiently. However, when the cells are pre-infected by E. coli, MAP is rapidly attracted from the subepithelial region to the cell surface. IL-1β production enhances the attraction of macrophages to the site of infection, where MAP benefits by infecting them.
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Krüger, Christin [Verfasser]. "Wirt-Erreger-Interaktionen in der klinisch inapparenten Phase nach oraler Inokulation von Ziegenlämmern mit Mycobacterium avium subsp. paratuberculosis: makroskopische, histologische und immunhistologische Befunde im zeitlichen Verlauf / Christin Krüger." Hannover : Bibliothek der Tierärztlichen Hochschule Hannover, 2014. http://d-nb.info/105438701X/34.
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Lefrançois, Louise. "Etude des adhésines HBHA et LBP impliquées dans l'interaction de Mycobacterium avium ssp. paratuberculosis avec les cellules épithéliales intestinales, cibles privilégiées de la bactérie in vivo." Thesis, Tours, 2012. http://www.theses.fr/2012TOUR4020/document.
Повний текст джерелаАнотація:
Mycobacterium avium ssp. paratuberculosis (Map), agent étiologique de la paratuberculose, a évolué en deuxtypes dénommés, S pour« Sheep » et C pour « Cattle ». L’intestin grêle est le site primaire de l’infection à Map mais les mécanismes moléculaires impliqués dans l’implantation du bacille restent largement méconnus. L’objectif de mon projet de thèse visait à identifier et caractériser les adhésines exprimées par Map par des approches génétiques et biochimiques. J’ai ainsi purifié la HBHA et la LBP par chromatographie d’affinité puis les ai identifiés en spectrométrie de masse. L’originalité de ce travail repose sur le polymorphisme de ces adhésines observé entre les souches de type C et S. Cette variabilité a été mise en évidence sur le domaine d’interaction avec les sucres sulfatés de la cellule hôte influençant l’affinité des adhésines pour l’héparine. Ce travail de thèse a permis de caractériser pour la première fois ces deux adhésines produites par Map. Le polymorphisme de la HBHA et de la LBP, discriminant les types C et S, ouvre de nombreuses perspectives sur l’évolution de l’espèce M. avium et le rôle de ces adhésines sur le tropisme intestinal, la préférence d’hôte de Map ou encore leur potentiel diagnosticMycobacterium avium subsp. paratuberculosis (Map), the etiological agent of paratuberculosis, has evolved into two types called, S for "Sheep" and C for "Cattle." The small intestine is the primary site of Map infection but the molecular mechanisms involved in the establishment of bacilli are still unknown. The aim of my thesis was to identify and characterize the adhesins expressed by Map by genetic and biochemical approaches. I purified HBHA and LBP by affinity chromatography then identified them by mass spectrometry. The originality of this work is based on the polymorphism of these adhesins observed between strains of type C and S. This variability has been demonstrated in the binding domain involved in interaction with sulfated sugars of host cell influences adhesins affinity for heparin. This thesis has characterized for the first time these two adhesins produced by Map. Specific polymorphism highlighted related to the evolution of the species avium, opens large number questions on their role on the pathogenesis of Map including the cellular tropism, host preference or interest of these antigens to improve diagnostic
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Schinköthe, Jan [Verfasser]. "Experimental oral infection of goats with Mycobacterium avium subsp. hominissuis: Pathomorphological characterization of lesions in different courses of disease with special focus on cellular composition of granulomas / Jan Schinköthe." Hannover : Bibliothek der Tierärztlichen Hochschule Hannover, 2015. http://d-nb.info/1080867880/34.
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Roller, Marco [Verfasser], Ralph [Akademischer Betreuer] Goethe, Claus-Peter [Akademischer Betreuer] Czerny, Ralph [Gutachter] Goethe, and Ursula [Gutachter] Siebert. "Vorkommen und Bedeutung von Mycobacterium avium subsp. paratuberculosis Infektionen in zoologischen Gärten : Literaturübersicht und Untersuchungen im Zoologisch-Botanischen Garten Wilhelma / Marco Roller ; Gutachter: Ralph Goethe, Ursula Siebert ; Ralph Goethe, Claus-Peter Czerny." Hannover : Stiftung Tierärztliche Hochschule Hannover, 2020. http://d-nb.info/1237685222/34.
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Sange, Marie Daniéle [Verfasser], Amir [Akademischer Betreuer] Abdulmawjood, Ursula [Akademischer Betreuer] Siebert, and Jochen [Akademischer Betreuer] Schulz. "Entwicklung, Validierung und Anwendung eines isothermalen Amplifikationssystems (LAMP) für die Detektion von Mycobacterium avium subsp. paratuberculosis (MAP) in kleinen Wiederkäuern und Genotypisierung mit MIRU-VNTR / Marie Daniéle Sange ; Amir Abdulmawjood, Ursula Siebert, Jochen Schulz." Hannover : Stiftung Tierärztliche Hochschule Hannover, 2019. http://d-nb.info/1202272436/34.
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Fiss, Letícia. "Paratuberculose em bovinos de corte na região Sul do Rio Grande do Sul: ocorrência e diagnóstico diferencial." Universidade Federal de Pelotas, 2015. http://repositorio.ufpel.edu.br:8080/handle/prefix/3269.
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Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq
Esta tese relata um surto de paratuberculose diagnosticado em bovinos de corte em uma propriedade na região Sul do Rio Grande do Sul. Foram descritos os aspectos epidemiológicos e clínico-patológicos da doença. Os animais eram criados extensivamente e apresentaram quadro de emagrecimento progressivo e diarreia crônica. O diagnóstico foi realizado pelas lesões macroscópicas e pela histopatologia. Fragmentos dos órgãos foram fixados em formalina 10%, incluídos em parafina, cortados com 5 μm de espessura e corados pela técnica de hematoxilina e eosina (HE) e Ziehl-Neelsen (ZN). Fezes foram encaminhadas ao Departamento de Medicina Veterinária, Área de Medicina Veterinária Preventiva da Universidade Federal Rural de Pernambuco para o cultivo de Mycobacterium avium subsp. paratuberculosis em meio Löwenstein Jensen com micobactina e para realização da PCR. Histologicamente havia enterite granulomatosa principalmente no dudeno, jejuno, íleo, ceco, colon e reto. Havia, ainda, linfangite e linfaadenite granulomatosa. Pela coloração de ZN foram observados numerosos bacilos álcool-ácido resistentes (BAAR) no interior de macrófagos, células gigantes de Langhans e nos linfonodos mesentéricos no duodeno, jejuno, íleo ceco e reto. Não houve crescimento bacteriano nas amostras de fezes e cinco amostras amplificaram a sequência genética IS900 específica do Mycobacterium avium subesp. paratuberculosis. Concluiu-se que a paratuberculose ocorre, também, em bovinos de corte criados extensivamente no sul do Rio Grande do Sul e pode ter uma prevalência maior do que se supõe na região, sendo necessárias medidas efetivas de controle desta doença que, por vezes, ainda é considerada exótica no Brasil. Por ser uma doença ainda pouco diagnosticada e pouco conhecida na região e que apresenta sinais clínicos inespecíficos, um segundo trabalho foi realizado visando determinar as principais doenças que ocorrem na região Sul do Rio Grande do Sul, que cursam com diarreia e afetam bovinos de corte maiores de dois anos de idade. Para isso realizou-se um levantamento nos arquivos do Laboratório Regional de Diagnóstico identificando-se os protocolos de necropsia nos quais era mencionada a diarreia como um sinal clínico relevante. Observou-se que as causas de diarreia em bovinos com dois anos ou mais de idade são poucas e bem conhecidas na região, sendo de fácil diagnóstico. Destaca-se a intoxicação por Senecio spp., em bovinos maiores de três anos, que causa prejuízos econômicos relevantes devido a sua ampla distribuição na região do estudo e ao seu difícil controle. Com relação aos bovinos entre dois e três anos as parasitoses de modo geral foram as mais importantes causas de diarreia representando 70% dos casos.
This thesis reports an outbreak of paratuberculosis diagnosed in beef cattle at a farm in the southern region of Rio Grande do Sul.
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Chandrakash, Saravanan. "A FR 13 microbiological global risk model: demonstrated for pasteurization of raw milk with viable Mycobacterium avium subsp. paratuberculosis." Thesis, 2017. http://hdl.handle.net/2440/111467.
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Steady-state unit-operations are used globally in chemical engineering processing. Importantly however, there are naturally occurring (random) fluctuations in parameter values about a ‘set’ mean. These are not sufficient to be considered transient and a random change in one is often off-set by a change in another - with the result that the output remains seemingly steady. Significantly, traditional chemical engineering does not address these random fluctuations explicitly. Davey and co-workers (e.g. Abdul Halim and Davey, 2015; Zou and Davey, 2016) have shown that these natural fluctuations can combine and accumulate in one direction and leverage unexpected and surprise behaviour across a ‘failure - not failure’ boundary. Their hypothesis they titled Fr 13 (Friday 13th) to underscore the surprise element of the failure event. Their probabilistic Fr 13 framework has been usefully applied to a number of 1-step unit-operations including failure in: UV irradiation for potable water (Abdul-Halim and Davey, 2015; 2016); thermal efficiency of a commercial coal-fired boiler (Davey, 2015), metals pitting (Davey et al., 2016), and; failure to remove whey protein deposits in Clean-In-Place milk processing (Davey et al., 2015). A significant advantage is that the framework can be used in quantitative ‘second-tier’ studies (Abdul-Halim and Davey, 2016) to improve design and safety of unit-operations. A limitation however is that the framework had been applied to only 1-step (single) unit-operations until very recently when Zou and Davey (2016) demonstrated its applicability to integrated 2-step membranes processing. Generally however, it is not known if there is any benefit in developing the framework as a useful tool for integrated, greater multi-step unit-operations and its possible combination (Davey et al., 2013) with existing software to enhance design capability. Davey (2011) had suggested these integrated multi-step analyses be termed ‘global’ models. A research program is therefore undertaken with the aim to advance the Fr 13 framework to gain unique insight into how naturally occurring fluctuations in apparent steady-state plant parameters can be transmitted and impact in progressively complex (in the context of ‘integrated’ not ‘complicated’) multi-step processes, and to assess the framework as a new design tool. A logical and stepwise approach is implemented as a research strategy. Because foods processing is globally the largest manufacturing sector, and within it, pasteurization is the most widely used unit-operation, a typical 3-step pasteurization unit operation, consisting of individual 1) heat-up, 2) holding and 3) cool-down, unit-operations is selected as a prudent and stringent test of the Fr 13 risk thesis to multi-step unit-operations. An initial assessment, based on typical commercial pasteurization equipment for raw milk (plate heat exchangers and an external-coil holding tube) is synthesized for the first time (Chandrakash et al., 2015; 2014; Davey et al., 2014) and a generalized method of notation for the Fr 13 risk framework is developed to unambiguously identify particular unit-operations in integrated multi-step processes. Failure is defined in terms of not meeting a globally used Regulatory combination of temperature (T) - time (t) (72 °C, 15 s). Results revealed that pasteurization of raw milk is vulnerable to failure in 12.5 % of all cases over the long-term as a result of with-in system fluctuations in flows, and thermal conditions. If each simulation is (reasonably) considered a daily process this translated to some 46 failures each year with a 2 % design tolerance 2 to meet the required T - t pasteurization criteria. Results highlighted that apparent steady-state pasteurization is actually a combination of successful and (potential) failed operations. This insight could not be obtained from existing traditional risk and hazard approaches, with or without sensitivity analyses. A drawback soon acknowledged however, is that this equipment model did not explicitly address the reduction in unwanted levels of survival of potential contaminant microorganisms in the treated milk. To overcome this, a microbiological global risk model is developed for the first time for the 3-step pasteurization. The logarithmic reduction of viable Mycobacterium avium subsp. paratuberculosis (MAP), a common bacterial contaminant and pathogen, is selected as an indicator of efficacy of process, and an inactivation model is then synthesized (Chandrakash and Davey, 2017 a). Results showed that for a design Regulatory reduction of log₁₀ = 5.5 in viable MAP the 3-step pasteurization is vulnerable to failure in 5.75 % of cases with a 2 % design tolerance averaged over the long term. This equated to ~ 21 failures with viable MAP each year based on a daily operation. To further test applicability of the risk framework to multi-step processing, a fourth integrated step, the storage of the pasteurized milk, is added for the first time (Chandrakash and Davey, 2017 b). A justification is that this simulated commercial practice more closely. Results of simulation of this 4-step model showed that with a design tolerance of 2 % for a Regulatory design reduction of log₁₀ = 5.5 in viable MAP on heat-up to 72 °C with 15 s holding in commercial plate equipment, there would be no further failures i.e. the rate of vulnerability to failure in a 4-step microbiological model for pasteurizing and storing milk remained 5.75 %, averaged over the long term. Results from investigative second-tier studies with the new 4-step Fr 13 model to improve design and safety, revealed vulnerability to microbiological failure can be readily mitigated by installing precise safety-integrity-level (SIL) mass flow control on the raw milk in existing plant to ensure a holding time of ≥ 15 s. It is concluded the Fr 13 framework appears generalizable to integrated multi-step steady-state processes without methodological problems and an advance over current existing risk/hazard methodologies. If properly developed, it is believed that this novel framework could be adopted as a new design tool for steady-state processing at both design and synthesis stages. Research findings will aid a detailed understanding of factors that contribute to failures, and to increased confidence in steady-state unit-operations processing. This research work is original and not incremental work. Findings will be of direct interest to risk analysts, milk processors and manufacturers of pasteurizer equipment.Thesis (Ph.D.) -- University of Adelaide, School of Chemical Engineering, 2017.