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Mycobacterium avium subsp. paratuberculosis: presencia en los alimentos y su relación con la enfermedad de Crohn
Cirone,K.; Morsella,C.; Romano,M.; Paolicchi,F.;
Revista argentina de microbiolog?-a , 2007,
Abstract: paratuberculosis or johne's disease is a chronic enteritis of the cattle and other small ruminant animals caused by mycobacterium avium subsp. paratuberculosis. in argentina, the strains were characterized in beef and dairy cattle and deer in different genetic patterns by molecular tools. m. avium subsp. paratuberculosis has been linked in men to a chronic inflammation of the intestine, named crohn's disease. there is clinical and experimental evidence to link m. avium subsp. paratuberculosis with crohn's disease by pcr, positive bacteriological culture from mother milk, blood and affected tissues by in situ hybridization. the milk and sub-products might be one of the possible infection sources and it has been suggested that m. avium subsp. paratuberculosis could resist pasteurization. several works showed that this mycobacteria could be present in retail milk of countries such as united kingdom, usa, czech republic, and recently in argentina. m. avium subsp. paratuberculosis was associated with different dairy products and water for human consumption. therefore, it is possible that these food sources may have a role for transmission. new investigations should emphasize the role of contaminated food and water in human infection around the world and determine the possible zoonotic role of m. avium subsp. paratuberculosis.
Localization of proteins in the cell wall of Mycobacterium avium subsp. paratuberculosis K10 by proteomic analysis
Zhiguo He, Jeroen De Buck
Proteome Science , 2010, DOI: 10.1186/1477-5956-8-21
Abstract: Mycobacterium avium subsp. paratuberculosis is a member of the M. avium complex, next to three other subspecies M. avium subsp. hominissuis, Mycobacterium avium subsp. avium and M. avium subsp. silvaticum and the species M. intracellulare. M. avium subspecies hominissuis and M. intracellulare are widely distributed in the environment and also inhabit healthy animal and human intestines, but do not usually cause disease unless the host is debilitated or immunocompromised. M. avium subsp. paratuberculosis, in contrast, is a pathogen which causes a debilitating chronic enteritis in ruminants[1] and has been implicated in Crohn's disease in humans [2]. Unfortunately, the mechanisms of virulence that control M. avium subsp. paratuberculosis persistence during infection are poorly understood and the key steps for developing paratuberculosis remain elusive. The current challenge is to identify elements that are essential for virulence and survival of the bacterium during infection, especially those that influence the immune responses against M. avium subsp. paratuberculosis.A characteristic feature of mycobacteria is the thick, waxy cell wall, a highly impermeable outer surface, which enables mycobacteria to survive in extreme environmental conditions and the presence of antibiotics. This cell wall contains 60% lipid, which confers on it the properties of acid fastness (the ability to resist decolorization by acidified alcohol), hydrophobicity, and increased resistance to chemicals (e.g. chlorine) and physical processes (e.g. pasteurization)[3].Bacterial surface proteins play a fundamental role in the interaction between the bacterial cell and its environment [4-6]. They are involved in adhesion to and invasion of host cells, in sensing the chemical and physical conditions of the external milieu and sending appropriate signals to the cytoplasmic compartment, in mounting defenses against host responses and in toxicity. In this study, we also aimed to identify surface-expose
Mycobacterium avium subsp. paratuberculosis: presencia en los alimentos y su relación con la enfermedad de Crohn Mycobacterium avium subsp. paratuberculosis in food and its relationship with Crohn's disease  [cached]
K. Cirone,C. Morsella,M. Romano,F. Paolicchi
Revista argentina de microbiolog?-a , 2007,
Abstract: La paratuberculosis o enfermedad de Johne es una enteritis crónica producida por Mycobacterium avium subsp. paratuberculosis, que afecta a bovinos y a otras especies. En la Argentina se ha caracterizado en rodeos bovinos y de ciervos, con aislamientos tipificados en distintos patrones genéticos. M. avium subsp. paratuberculosis ha sido vinculado en humanos con una inflamación crónica del intestino, denominada enfermedad de Crohn. Existen evidencias clínicas y experimentales que relacionan a M. avium subsp. paratuberculosis con la enfermedad en el humano, mediante su detección por PCR y por cultivo a partir de biopsias de órganos, de leche materna y de sangre de pacientes afectados. La leche y sus subproductos serían posibles fuentes de infección y se ha sugerido que M. avium subsp. paratuberculosis resistiría las condiciones de pasteurización. Diversos trabajos de investigación demostraron que esta micobacteria podría estar presente en leches comercializadas en diversos países, como Reino Unido, Estados Unidos, República Checa, y también en la Argentina. La presencia de M. avium subsp. paratuberculosis en productos lácteos y agua de consumo ha sido relacionada con la resistencia del microorganismo tanto a los procesos de elaboración como a los factores climáticos adversos, lo que enfatiza el rol de los alimentos y del agua como vías de transmisión al humano. Las investigaciones en curso podrían ratificar el riesgo y las implicancias de la exposición del humano a M. avium subsp. paratuberculosis a través de los alimentos y del agua contaminados, para determinar la importancia de la paratuberculosis como enfermedad zoonótica. Paratuberculosis or Johne's disease is a chronic enteritis of the cattle and other small ruminant animals caused by Mycobacterium avium subsp. paratuberculosis. In Argentina, the strains were characterized in beef and dairy cattle and deer in different genetic patterns by molecular tools. M. avium subsp. paratuberculosis has been linked in men to a chronic inflammation of the intestine, named Crohn's disease. There is clinical and experimental evidence to link M. avium subsp. paratuberculosis with Crohn's disease by PCR, positive bacteriological culture from mother milk, blood and affected tissues by in situ hybridization. The milk and sub-products might be one of the possible infection sources and it has been suggested that M. avium subsp. paratuberculosis could resist pasteurization. Several works showed that this mycobacteria could be present in retail milk of countries such as United Kingdom, USA, Czech Republic, and recently in
Dynamics of Specific Anti-Mycobacterium avium Subsp. paratuberculosis Antibody Response through Age  [PDF]
S?ren Saxmose Nielsen, Nils Toft, Hisako Okura
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0063009
Abstract: Mycobacterium avium subsp. paratuberculosis (MAP) causes a chronic infection in cattle. MAP infected cattle with humoral immune (HI) reactions with IgG antibodies are usually those where latency of infection has ceased and their infection is progressing towards reduced milk yield, weight loss and significant bacterial excretion in feces. The proportion of detectable infections among all infected animals that will develop disease is often referred to as ‘the tip of the iceberg’. The purpose of this study was to estimate this proportion. Test-records from 18,972 Danish dairy cows with MAP specific IgG antibodies on their final test-record were used to estimate age-specific sensitivities (Se). These cows were the infected ones considered to develop disease in a population with a representative age-distribution and were defined as cases. The specificity (Sp) of the test was estimated based on test-results from 166,905 cows, which had no MAP IgG antibodies in their final four test-records. The Sp, age-specific Se and maximum Se were used to estimate the probability of having HI at a given age resulting in the proportion of infected cows with HI at a given age. For cows 2 years of age, the proportion of detectable cases was 0.33, while it was 0.94 for cows 5 years of age. Thus, there was a significant shift in the tip of the iceberg with aging. This study provided a model for estimating the proportion of latent chronic infections that would progress to disease, and the results can be used to model infection dynamics.
Immunoreactivity of the Mycobacterium avium subsp. paratuberculosis 19-kDa lipoprotein
Jason FJ Huntley, Judith R Stabel, John P Bannantine
BMC Microbiology , 2005, DOI: 10.1186/1471-2180-5-3
Abstract: MAP0261c is conserved in mycobacteria, showing a 95% amino acid identity in M. avium subspecies avium, 84% in M. intracellulare and 76% in M. bovis and M. tuberculosis. MAP0261c was cloned, expressed, and purified as a fusion protein with the maltose-binding protein (MBP-19 kDa) in Escherichia coli. IFN-γ production was measured from 21 naturally infected and 9 control cattle after peripheral blood mononuclear cells (PBMCs) were stimulated with a whole cell lysate (WCL) of M. avium subsp. paratuberculosis or the recombinant MBP-19 kDa. Overall, the mean response to MBP-19 kDa was not as strong as the mean response to the WCL. By comparison, cells from control, non-infected cattle did not produce IFN-γ after stimulation with either WCL or MBP-19 kDa. To assess the humoral immune response to the 19-kDa protein, sera from cattle with clinical Johne's disease were used in immunoblot analysis. Reactivity to MBP-19 kDa protein, but not MBP alone, was observed in 9 of 14 infected cattle. Antibodies to the 19-kDa protein were not observed in 8 of 9 control cows.Collectively, these results demonstrate that while the 19-kDa protein from M. avium subsp. paratuberculosis stimulates a humoral immune response and weak IFN-γ production in infected cattle, the elicited responses are not strong enough to be used in a sensitive diagnostic assay.Paratuberculosis (Johne's disease) is caused by Mycobacterium avium subsp. paratuberculosis (referred to hereafter as M. avium subsp. paratuberculosis) and induces a chronic enteritis in ruminants. The disease signs include weight loss, diarrhea, and decreased milk production. In the United States alone the economic burden of Johne's disease is estimated at over $200 million in lost annual revenue to the dairy industry [1]. Prevalence studies in the United States have estimated that between 20 to 30% of dairy herds are infected with M. avium subsp. paratuberculosis [2,3]. Neonatal calves are most susceptible to infection and are likely to beco
MYCOBACTERIUM AVIUM SUSP. PARATUBERCULOSIS IN DAIRY PRODUCTION  [cached]
G. Marchetti,A. Coccollone,F. Giacometti,R. Riu
Italian Journal of Food Safety , 2012, DOI: 10.4081/ijfs.2012.4.7
Abstract: Mycobacterium avium subsp. paratuberculosis (MAP) is the etiologic agent of paratuberculosis. The disease affects cows and other ruminants and causes high economic losses, mainly for dairy production. MAP may also have a role in the development of Crohn’s disease in humans. Infected animals shed viable MAP with milk and faeces and humans may assume MAP via the consumption of contaminated milk and dairy products. Current methods of milk pasteurization are not sufficient to kill all MAP cells present in milk and MAP has been found in raw or pasteurized milk and isolated from cheese. The aim of this paper is to review the current knowledge about MAP in dairy production. We analyzed studies on milk contamination, effect of pasteurization and methods for identification of MAP that can be applied to dairy products.
Hepatite granulomatosa em bovino causada por Mycobacterium avium subsp. paratuberculosis
Rodrigues, A.B.F;Ristow, P;Santos, A.S.O;Lilenbaum, W;Fonseca, L.S;Carvalho, C.B;Carvalho, E.C.Q;
Arquivo Brasileiro de Medicina Veterinária e Zootecnia , 2010, DOI: 10.1590/S0102-09352010000600029
Abstract: samples from intestines, liver, and lymph nodes were collected from a dairy steer with clinical suspicion of paratuberculosis. the samples were processed for histologic examination with hematoxylin-eosin and zihel-neelsen (zn) staining for the detection of acid-fast bacilli (afb), and submitted to immunohistochemistry (ihc). macroscopic changes were observed in the small intestines, with thickening and corrugation of the mucosa. the main microscopic changes were found in small intestines, lymph vessels in the mesentery, and mesenteric lymph nodes characterized by enteritis, lymphangiectasia, and lymphadenitis. liver presented with granulomatous hepatitis, an uncommon histopathological feature for paratuberculosis. the clinical features associated with positive culture of mycobacterium avium subsp. paratuberculosis and detection of afb by zn and ihc in the cytoplasm of macrophages (epithelioid) in the intestinal mucosa and submucosa, lymph nodes, and liver were important to confirm the diagnosis of paratuberculosis.
Evaluation of Mycobacterium avium subsp. paratuberculosis faecal culture protocols and media
Ristow, Paula;Silva, Marlei Gomes;Fonseca, Leila de Souza;Lilenbaum, Walter;
Pesquisa Veterinária Brasileira , 2006, DOI: 10.1590/S0100-736X2006000100001
Abstract: paratuberculosis is an important enteritis of ruminants caused by mycobacterium avium subsp. paratuberculosis (map). the disease is officially considered exotic in brazil, but recent serological surveys and the isolation of the agent suggest it may occur in our herds. the aim of this study was to evaluate three different formulations of herrold's egg yolk agar with mycobactin j (heym) and four faecal culture protocols considering their ability for map growth as well as cost and ease of application. three formulations of heym were inoculated with two suspensions of map. spiked faeces and naturally contaminated faecal samples were treated by the four faecal culture protocols. centrifugation protocol and heym recommended by oie showed the best results on the recovery of map.
Evaluation of Mycobacterium avium subsp. paratuberculosis faecal culture protocols and media
Ristow Paula,Silva Marlei Gomes,Fonseca Leila de Souza,Lilenbaum Walter
Pesquisa Veterinária Brasileira , 2006,
Abstract: Paratuberculosis is an important enteritis of ruminants caused by Mycobacterium avium subsp. paratuberculosis (Map). The disease is officially considered exotic in Brazil, but recent serological surveys and the isolation of the agent suggest it may occur in our herds. The aim of this study was to evaluate three different formulations of Herrold's egg yolk agar with mycobactin J (HEYM) and four faecal culture protocols considering their ability for Map growth as well as cost and ease of application. Three formulations of HEYM were inoculated with two suspensions of Map. Spiked faeces and naturally contaminated faecal samples were treated by the four faecal culture protocols. Centrifugation protocol and HEYM recommended by OIE showed the best results on the recovery of Map.
Detection of Mycobacterium avium subsp. paratuberculosis in asymptomatic bovines by IS900 Polymerase Chain Reaction
Remya Raveendran,Priya P.M.,Koshy John,Krishnan Nair G
Veterinary World , 2011,
Abstract: Faecal samples were collected from 58 asymptomatic bovines and after DNA extraction IS900 Polymerase Chain Reaction (IS900 PCR) was performed to detect Mycobacterium avium subsp. paratuberculosis (MAP). Ten samples (17.24 %) were positive for MAP. The results indicated that the IS900 PCR assay can be used for the early diagnosis of bovine paratuberculosis. [Vet. World 2011; 4(6.000): 248-249]
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