| mycobacterium avium subsp. paratuberculosis: pathogen, pathogenesis and diagnosis. | johne's disease, or paratuberculosis, is a chronic intestinal infection caused by mycobacterium avium subsp. paratuberculosis. the usually fatal disease is characterised by cachexia, and in some species diarrhoea, after a long pre-clinical phase. treatment is ineffective and economically impracticable. the infection primarily affects domestic and free-ranging ruminants, but has also been reported in primates, rabbits, stoats and foxes. since paratuberculosis is often subclinical, under-reporting ... | 2001 | 11288509 |
| control of mycobacterium avium subsp. paratuberculosis infection in agricultural species. | paratuberculosis or johne's disease is a chronic intestinal disease caused by mycobacterium avium subsp. paratuberculosis, which continues to spread in agricultural species. control of paratuberculosis is challenging and should not be underestimated. due to the long incubation period of the infection, disease is largely subclinical in domesticated livestock. hence, direct effects on animal productivity and welfare are often masked and may appear insufficient to justify large investments in contr ... | 2001 | 11288510 |
| comparison of two enzyme-linked immunosorbent assays for serologic diagnosis of paratuberculosis (johne's disease) in cattle using different subspecies strains of mycobacterium avium. | serologic diagnosis of bovine paratuberculosis (johne's disease) with currently available tests may give false-positive results due to cross-reactions with avian and bovine tuberculosis viruses and other infectious agents. indirect enzyme-linked immunosorbent assays (elisa) for detection of antibodies against paratuberculosis based on antigens from mycobacterium avium subsp. avium (a-elisa) and m. avium subsp. paratuberculosis (p-elisa) were compared. despite an expected higher specificity for m ... | 2001 | 11289215 |
| presence of mycobacterium avium subspecies paratuberculosis in suspensions of ovine trichostrongylid larvae produced in faecal cultures artificially contaminated with the bacterium. | a reference strain of mycobacterium avium subspecies paratuberculosis was added to faecal larval cultures of haemonchus contortus, ostertagia circumcincta and trichostrongylus colubriformis. samples of the larvae produced were cultured for the presence of the bacterium in modified bactec 12b medium, both before and after exposure to gamma irradiation. the water used to wash the larvae off the faecal cultures was also tested for the presence of the bacterium. positive growth was confirmed as m. a ... | 2001 | 11292085 |
| progress towards a rapid polymerase chain reaction diagnostic test for the identification of mycobacterium avium subsp. paratuberculosis in faeces. | hybridization-capture polymerase chain reaction (hc-pcr), a nucleic acid sequence capture technique, was evaluated on faecal samples pooled from 50 sheep and individual faecal samples as a rapid diagnostic test for mycobacterium avium subsp. paratuberculosis, the causative agent of johne's disease. the status of each of the faecal samples was determined by radiometric culture. a simpler direct-pcr technique was evaluated on the same samples and was found to be more sensitive than hc-pcr. the lac ... | 2001 | 11292329 |
| evaluation of a commercial elisa for diagnosis of paratuberculosis in cattle. | to evaluate sensitivity and specificity of a new elisa for antibodies against mycobacterium avium subsp paratuberculosis. | 2001 | 11318370 |
| sensitive differential detection of genetically related mycobacterial pathogens in archival material. | a polymerase chain reaction (pcr) assay targeted to the immunogenic protein mpb64 gene was used to detect members of the mycobacterium tuberculosis complex, and an outward-primed pcr (oppcr) designed on the is6110 element allowed differentiation between mycobacterium bovis and mycobacterium tuberculosis. additionally, the amplification of is1110 and 16s ribosomal rna sequences combined with a dot blotting assay were able to differentially detect mycobacterium avium, mycobacterium intracellulare, ... | 2000 | 11338484 |
| progress towards understanding the spread, detection and control of mycobacterium avium subsp paratuberculosis in animal populations. | to review and interpret aspects of the pathogenesis and epidemiology of paratuberculosis (johne's disease) for veterinarians involved in current johne's disease control programs. | 2001 | 11349414 |
| the grazing response of cattle to pasture contaminated with rabbit faeces and the implications for the transmission of paratuberculosis. | transmission of mycobacterium avium subspecies paratuberculosis, the organism responsible for paratuberculosis (or johne's disease) in ruminants, occurs through the faecal-oral route. as m. a. paratuberculosis has been isolated from rabbit faeces, cattle grazing rabbit faecal contaminated pasture may thus be at risk.a herd of 57 beef cattle was monitored on a farm in perthshire, throughout the 1999 'grazing year', to investigate whether the cattle avoided rabbit faecal contaminated pasture and t ... | 2001 | 11352488 |
| typing of is 1311 polymorphisms confirms that bison (bison bison) with paratuberculosis in montana are infected with a strain of mycobacterium avium subsp. paratuberculosis distinct from that occurring in cattle and other domesticated livestock. | isolates of mycobacterium avium subsp. paratuberculosis from nine bison (bison bison) from montana, united states of america, were compared with those from other species from the united states of america. all 16 isolates had a novel is 1311 genotype in which all copies of the element possessed a thymidine-cytosine nucleotide variation at base position 223. isolates from bison were termed b strain. thirteen isolates from cattle and goats were polymorphic at this locus, a status previously recogni ... | 2001 | 11352594 |
| an evaluation of a modified interferon-gamma assay for the detection of paratuberculosis in dairy herds. | whole blood samples were obtained from multiple dairy herds in pennsylvannia and in wisconsin which were previously determined to be infected with mycobacterium paratuberculosis (mps) (johne's disease) by fecal culture. blood samples were shipped overnight to the national animal disease center (nadc) in ames, ia for processing and interferon-gamma (ifn-gamma) analysis. blood samples were incubated alone (non-stimulated) or with concanavalin a (cona), a t-cell mitogen used as a positive control i ... | 2001 | 11356251 |
| detection of mycobacterium avium subspecies paratuberculosis in crohn's diseased tissues by in situ hybridization. | reports about the association between crohn's disease (cd) and cell wall-deficient (cwd) forms of mycobacterium avium subspecies paratuberculosis (m. paratuberculosis) are controversial. this may be due to the heterogeneous nature of cd where only about 50% of the patients show granulomatous inflammation. detection of cwd forms of m. paratuberculosis in tissues from patients with cd would support its association with the disease. to help identify these forms in inflamed tissues, a previously dev ... | 2001 | 11374694 |
| inactivation of mycobacterium paratuberculosis by pulsed electric fields. | the influence of treatment temperature and pulsed electric fields (pef) on the viability of mycobacterium paratuberculosis cells suspended in 0.1% (wt/vol) peptone water and in sterilized cow's milk was assessed by direct viable counts and by transmission electron microscopy (tem). pef treatment at 50 degrees c (2,500 pulses at 30 kv/cm) reduced the level of viable m. paratuberculosis cells by approximately 5.3 and 5.9 log(10) cfu/ml in 0.1% peptone water and in cow's milk, respectively, while p ... | 2001 | 11375202 |
| etiology of crohn's disease: the role of mycobacterium avium paratuberculosis. | crohn's disease is a chronic inflammatory bowel disease characterized by transmural inflammation and granuloma formation. several theories regarding the etiology of crohn's disease have been proposed, one of which is infection with mycobacterium avium subspecies paratuberculosis (m. paratuberculosis), which causes a similar disease in animals, and is present in the human food chain. considerable evidence supports the presence of m. paratuberculosis in the intestinal tissues of many patients with ... | 2001 | 11378513 |
| detection of mycobacterium avium subsp. paratuberculosis in tissue samples by single, fluorescent and nested pcr based on the is900 gene. | the aim of this study was to determine if fluorescent pcr could be used instead of nested pcr, for the detection of mycobacterium avium subsp. paratuberculosis (m. paratuberculosis) in clinical specimens, to improve the sensitivity without increasing the risk for cross-contamination. we investigated and compared the sensitivity of single pcr, fluorescent pcr and nested pcr for the detection of is900, an insertion sequence specific for m. paratuberculosis. a previously described extraction method ... | 2001 | 11390109 |
| recovery of mycobacterium avium subsp. paratuberculosis from nematode larvae cultured from the faeces of sheep with johne's disease. | a study was conducted to determine whether trichostrongylid nematode larvae become contaminated with mycobacterium avium subsp. paratuberculosis when they develop in the faeces of sheep with johne's disease. nematode larvae were hatched from ova in the faecal samples of affected sheep. larval sheaths were removed and these as well as exsheathed larvae were subjected to radiometric culture for m. paratuberculosis. the organism was recovered from washing water used to prepare the larvae, third sta ... | 2001 | 11390110 |
| [integrated disease control in dairy herds. a case study from the veterinarians' viewpoint]. | integrated control of bovine virus diarrhoea virus, bovine herpesvirus-1, leptospira interrogans serovar hardjo subtype hardjobovis, mycobacterium avium subsp. paratuberculosis, and salmonella dublin in dairy herds may provide economic benefits superior to those obtained by sequential disease control, because, among other things, it allows optimization of voluntary culling. however, in practice there are no adequate instruments to establish priorities in voluntary culling. therefore, in this stu ... | 2001 | 11392987 |
| immune reactions in cattle after immunization with a mycobacterium paratuberculosis vaccine and implications for the diagnosis of m. paratuberculosis and m. bovis infections. | after immunization of four calves with a live modified mycobacterium paratuberculosis vaccine the course of the humoral and cell mediated immune reactions was studied during a 2-year clinical investigation. furthermore, the possibility of shedding of the vaccine strain and the influence of the vaccination on the tuberculin skin test was determined. in addition to standard procedures recently developed diagnostic methods (antibody enzyme-linked immunosorbent assay, interferon-gamma test, polymera ... | 2001 | 11393814 |
| ahpc, ahpd, and a secreted 14-kilodalton antigen from mycobacterium avium subsp. paratuberculosis distinguish between paratuberculosis and bovine tuberculosis in an enzyme-linked immunosorbent assay. | sera from cattle naturally infected with mycobacterium avium subsp. paratuberculosis (n = 56) and naturally (n = 4) and experimentally (n = 8) infected with mycobacterium bovis were tested for the presence of antibodies against paratuberculosis antigens. an enzyme-linked immunosorbent assay (elisa) was established based on absorption of m. avium subsp. paratuberculosis antigens on a hyperimmune antiserum against m. avium subsp. avium proteins in order to remove cross-reacting antigens. this abso ... | 2001 | 11427429 |
| mycobacterium avium subsp. paratuberculosis in veterinary medicine. | mycobacterium avium subsp. paratuberculosis (basonym m. paratuberculosis) is the etiologic agent of a severe gastroenteritis in ruminants known as johne's disease. economic losses to the cattle industry in the united states are staggering, reaching $1.5 billion annually. a potential pathogenic role in humans in the etiology of crohn's disease is under investigation. in this article, we review the epidemiology, pathogenesis, diagnostics, and disease control measures of this important veterinary p ... | 2001 | 11432810 |
| natural paratuberculosis infection in rabbits in scotland. | natural paratuberculosis infection of rabbits (oryctolagus cuniculus) was recently diagnosed in scotland, and an investigation into the pathology of the disease in wild rabbits is reported in this paper. evidence of mycobacterium avium subsp. paratuberculosis (m.a. paratuberculosis) infection was detected in 22% of 110 rabbits; the organism was cultured from 17 of 110 rabbits, and histopathological lesions consistent with m.a. paratuberculosis infection were noted in 18 of 98 rabbits examined. n ... | 2001 | 11437505 |
| intracellular trafficking of mycobacterium avium ss. paratuberculosis in macrophages. | the granulomatous enteric lesions of cattle with johne's disease are composed of infected macrophages, and grow by accumulation, re-infection, and expansion of macrophage populations in the intestinal wall. we have examined the growth of bacteria in macrophages to define characteristics of intracellular trafficking for exocytosis, replication, and antigen presentation. using immunocytochemical markers for light, confocal and electron microscopy, we have examined potential pathway tropisms using ... | 2001 | 11449907 |
| subclinical paratuberculosis in goats following experimental infection. an immunological and microbiological study. | an experimental oral infection of goats with a caprine isolate of mycobacterium a. subsp. paratuberculosis was used to investigate immunological and bacteriological events during the subclinical phase of infection. seven goats at 5-8 weeks of age were given a bacterial suspension in milk-replacement three times weekly for 9 weeks. six animals were kept as controls. cellular recall responses against m. a. paratuberculosis were analysed by means of a lymphocyte proliferation test, an ifn-gamma ass ... | 2001 | 11457480 |
| characterization of the intracellular survival of mycobacterium avium ssp. paratuberculosis: phagosomal ph and fusogenicity in j774 macrophages compared with other mycobacteria. | the phagosomes containing viable pathogenic mycobacteria, such as mycobacterium (m.) tuberculosis and mycobacterium avium ssp. avium (m. avium), are known to be limited in their ability to both acidify and fuse with late (but not early) endocytic organelles. here, we analysed the ph and fusogenicity of phagosomes containing m. avium ssp. paratuberculosis (m. ptb), the causative agent of paratuberculosis in ruminants. using the murine j774 macrophage cell line, we compared viable and heat-killed ... | 2001 | 11488816 |
| health protocol for translocation of free-ranging elk. | when considering an elk (cervus elaphus) restoration program, wildlife managers must evaluate the positive and negative elements of translocation. we prepared this protocol to give an overview of health considerations associated with translocation of elk, with an emphasis on movement of free-ranging elk from western north america to the southeastern usa. we evaluated infectious agents and ectoparasites reported in elk from two perspectives. first, we made a qualitative estimate of the ability of ... | 2001 | 11504216 |
| [eradication of paratuberculosis in dairy herds: determination of the initial herd prevalence and modelling of prevalence development]. | a prerequisite for the success of any eradication programme is the accurate determination of the initial herd prevalence as well as a herd-specific prediction of prevalence development. this prerequisite is not currently given for the eradication of paratuberculosis in infected herds. in the work presented a method to predict the initial paratuberculosis prevalence in infected herds is presented; it is based on the formation of two groups (elisa-positive and negative) and the determination of ge ... | 2001 | 11505846 |
| prevalence of antibodies against mycobacterium avium subsp paratuberculosis among beef cow-calf herds. | to estimate the prevalence of mycobacterium avium subsp paratuberculosis infection among cows on beef operations in the united states. | 2001 | 11518178 |
| identification of a secreted superoxide dismutase in mycobacterium avium ssp. paratuberculosis. | mycobacterium avium ssp. paratuberculosis (m. paratuberculosis), the causative agent of johne's disease, is an important animal pathogen that has also been implicated in human disease. the major proteins expressed by m. paratuberculosis were analyzed by two-dimensional gel electrophoresis, and a superoxide dismutase (sod) was identified from this protein profile. the m. paratuberculosis sod has a molecular mass of 23 kda and an isoelectric point of 6.1. sequence analysis of the corresponding sod ... | 2001 | 11520620 |
| effect of turbulent-flow pasteurization on survival of mycobacterium avium subsp. paratuberculosis added to raw milk. | a pilot-scale pasteurizer operating under validated turbulent flow (reynolds number, 11,050) was used to study the heat sensitivity of mycobacterium avium subsp. paratuberculosis added to raw milk. the atcc 19698 type strain, atcc 43015 (linda, human isolate), and three bovine isolates were heated in raw whole milk for 15 s at 63, 66, 69, and 72 degrees c in duplicate trials. no strains survived at 72 degrees c for 15 s; and only one strain survived at 69 degrees c. means of pooled d values (dec ... | 2001 | 11525992 |
| fate of mycobacterium avium subsp. paratuberculosis in swiss hard and semihard cheese manufactured from raw milk. | raw milk was artificially contaminated with declumped cells of mycobacterium avium subsp. paratuberculosis at a concentration of 10(4) to 10(5) cfu/ml and was used to manufacture model hard (swiss emmentaler) and semihard (swiss tisliter) cheese. two different strains of m. avium subsp. paratuberculosis were tested, and for each strain, two model hard and semihard cheeses were produced. the survival of m. avium subsp. paratuberculosis cells was monitored over a ripening period of 120 days by pla ... | 2001 | 11526024 |
| experimental paratuberculosis in calves following inoculation with a rabbit isolate of mycobacterium avium subsp. paratuberculosis. | the role of wildlife species in the epidemiology of paratuberculosis has been the subject of increased research efforts following the discovery of natural paratuberculosis in free-living rabbits from farms in east scotland. this paper describes the experimental inoculation of young calves with an isolate of mycobacterium avium subsp. paratuberculosis recovered from a free-living rabbit. after a 6-month incubation period, all eight calves inoculated with the rabbit isolate had developed histopath ... | 2001 | 11526132 |
| [current paratuberculosis management by the health department]. | | 2001 | 11544930 |
| comparison of immunomagnetic bead separation-polymerase chain reaction and faecal culture for the detection of mycobacterium avium subsp paratuberculosis in sheep faeces. | | 2001 | 11549050 |
| identification of two mycobacterium avium subspecies paratuberculosis gene products differentially recognised by sera from rabbits immunised with live mycobacteria but not heat-killed mycobacteria. | the investigation of environmentally regulated proteins has led to a better understanding of host-pathogen interactions and identified novel vaccine candidate antigens for several bacterial pathogens. in an effort to identify such proteins in mycobacterium avium subsp. paratuberculosis (m. paratuberculosis), a genomic expression library was differentially screened with sera from rabbits that had been immunised with live m. paratuberculosis (alpha-live) as well as sera from rabbits immunised with ... | 2001 | 11549181 |
| identification, cloning and expression of sodc from an alkaline phosphatase gene fusion library of mycobacterium avium subspecies paratuberculosis. | the phoa gene technology was used to investigate secreted proteins of the intracellular pathogen mycobacteriumn avium subspecies paratuberculosis. this led to the identification of sodc, a gene which codes for a copper and zinc cofactored superoxide dismutase (cu,znsod) which has been implicated as a virulence factor for some pathogens. the predicted protein possessed a 76% identity with cu,znsod of mycobacterium tuberculosis. to characterize cu,znsod from m. avium subspecies paratuberculosis, t ... | 2001 | 11549243 |
| comparative evaluation of four decontamination protocols for the isolation of mycobacterium avium subsp. paratuberculosis from milk. | four chemical decontamination protocols for milk were compared with respect to mean percentage recovery of spiked mycobacterium avium subsp. paratuberculosis, minimum detection limit and ease of application. | 2001 | 11555198 |
| bactericidal effect of chlorine on mycobacterium paratuberculosis in drinking water. | one possible route of transmission of mycobacterium paratuberculosis from cattle to humans is via contaminated water supplies. the aim of this work was to determine whether this organism can survive standard water treatment processes. | 2001 | 11555209 |
| innate ifn-gamma production in cattle in response to mpp14, a secreted protein from mycobacterium avium subsp. paratuberculosis. | calves experimentally infected with mycobacterium avium subsp. paratuberculosis and uninfected calves were tested for interferon(ifn)-gamma production after stimulation with purified protein derivative from m. avium subsp. paratuberculosis (ppdp) or a secreted 14 kda protein (mpp14) specific for the m. avium-intracellulare-scrofulaceum (mais) complex. several calves in both groups responded strongly up to about 5 months to both antigens. two uninfected calves responded repeatedly, but not always ... | 2001 | 11555395 |
| cytokine gene expression in ileal tissues of cattle infected with mycobacterium paratuberculosis. | cytokine gene expression in ileal tissues of cattle infected with mycobacterium paratuberculosis was evaluated. the effects of infection with m. paratuberculosis on cytokine production may influence immune regulation at the site of colonization, resulting in the chronic inflammatory state associated with the latter stages of this disease. ileal samples were obtained at necropsy from noninfected control cows (n=8) and clinically infected cows (n=7) and processed for immunohistochemistry and in si ... | 2001 | 11557295 |
| heat inactivation data for mycobacterium avium subsp. paratuberculosis: implications for interpretation. | we discuss several factors that are critical for heat inactivation experiments and which should be taken into account for future research. | 2001 | 11576307 |
| t cell-dependent inducible nitric oxide synthase production and ultrastructural morphology in balb/c mice infected with mycobacterium avium subspecies paratuberculosis. | euthymic balb/c and athymic nude balb/c mice aged 3-8 days were infected intraperitoneally with mycobacterium avium subspecies paratuberculosis (atcc strain 19698). after euthanasia at 5 months post-inoculation, hepatic granulomas were evaluated by morphometric analysis of digital images captured from light microscopy sections, by electron microscopy and by immunohistochemical methods. euthymic mice differed from athymic mice in that (1) their hepatic granulomas were smaller, contained fewer bac ... | 2001 | 11578129 |
| an enzyme-linked immunosorbent assay using immonoaffinity-purified antigen in the diagnosis of caprine paratuberculosis and its comparison with conventional elisas. | an enzyme-linked immunosorbent assay (apa-elisa) using an immunoaffinity-purified antigen was developed and compared with the unabsorbed and absorbed elisa procedures, using a crude antigenic preparation, for its efficacy in detecting antibodies in goat sera against mycobacterium ovium paratuberculosis. serum samples from 89 goats belonging to three different flocks, two with a history and evidence of paratuberculosis and one without it, were subjected to each elisa, which had been standardized ... | 2001 | 11583377 |
| the esat-6 gene cluster of mycobacterium tuberculosis and other high g+c gram-positive bacteria. | the genome of mycobacterium tuberculosis h37rv has five copies of a cluster of genes known as the esat-6 loci. these clusters contain members of the cfp-10 (lhp) and esat-6 (esat-6) gene families (encoding secreted t-cell antigens that lack detectable secretion signals) as well as genes encoding secreted, cell-wall-associated subtilisin-like serine proteases, putative abc transporters, atp-binding proteins and other membrane-associated proteins. these membrane-associated and energy-providing pro ... | 2001 | 11597336 |
| [modelling of prevalence development in a paratuberculosis control program in a dairy herd]. | a modelling approach to calculate the success of a paratuberculosis control programme in dairy herds is presented. the essential parameters of the model are the prevalence at the beginning of the programme, diagnostic sensitivity and specificity of the tests used, discipline in culling test-positive animals, turnover in the herd, percentage of replacement with own stock and paratuberculosis prevalence in animals bought into the herd from outside, and a general hygiene-based factor. diagnostic me ... | 2001 | 11599437 |
| dietary effects on the microbiological safety of food. | the high mortality rate associated with human infections caused by escherichia coli strains of the serotype o157:h7 has brought to public attention the importance of ruminants as reservoirs of food-borne pathogens. in addition to established examples such as salmonella, campylobacter and listeria, recent evidence is emerging of the role of food in the transmission of helicobacter pylori and mycobacterium paratuberculosis. food-borne pathogens harboured by ruminants are spread through shedding in ... | 2001 | 11681640 |
| the effect of subclinical mycobacterium paratuberculosis infection on milk production in michigan dairy cows. | the objective of this study was to determine the effect of subclinical mycobacterium paratuberculosis infection on mature equivalent milk, protein, and fat production in a sample of michigan dairy herds with a history of cows positive for m. paratuberculosis diagnosed by fecal culture. a prospective two-group cohort study was conducted. participating herds were tested, and productivity and reproduction records were monitored for 18 mo. all cows aged 24 mo and greater were tested for m. paratuber ... | 2001 | 11699450 |
| protagonist. mycobacterium avium subspecies paratuberculosis is a cause of crohn's disease. | | 2001 | 11709506 |
| antagonist. mycobacterium avium subspecies paratuberculosis is a cause of crohn's disease. | | 2001 | 11709507 |
| survival of mycobacterium avium subsp paratuberculosis in amitraz cattle dip fluid. | to determine the survival time of mycobacterium avium subsp paratuberculosis in amitraz-based cattle dip fluid derived from an active dip site in northern new south wales. | 2001 | 11712711 |
| identification of mycobacterium avium subsp. paratuberculosis in biopsy specimens from patients with crohn's disease identified by in situ hybridization. | crohn's disease is a chronic inflammatory disease of the gastrointestinal tract of unknown etiology. we report on the presence of cell wall-deficient mycobacterium avium subsp. paratuberculosis in 35 of 48 paraffin-embedded tissue specimens from 33 patients with crohn's disease by in situ hybridization with is900 as a probe. | 2001 | 11724871 |
| antigen-induced production of interferon-gamma in samples of peripheral lymph nodes from sheep experimentally inoculated with mycobacterium avium subsp. paratuberculosis. | the production of interferon-gamma (ifn-gamma) in response to johnin purified protein derivate was measured in samples of the prescapular lymph node (pln) from 10 sheep, aged 2 years, and nine sheep, aged 1 year that had been inoculated orally with mycobacterium avium subsp. paratuberculosis within their first month of life. ten non-inoculated sheep, aged 1 year, constituted the negative control group. the results obtained in the pln ifn-gamma assay were compared with those derived from serologi ... | 2002 | 11731176 |
| how does mycobacterium avium subsp. paratuberculosis resist intracellular degradation? | paratuberculosis is a chronic, progressive disease of mainly ruminants caused by the facultative intracellular bacterium, mycobacterium avium subsp. paratuberculosis. infection usually occurs in young animals through oral uptake of food contaminated with the organisms. the ingested bacteria are transcytosed through m-cells overlying the peyer's patches and are released in the stroma, where they are taken up by macrophages. inside the macrophage, the mycobacteria resist enzymatic and toxic degrad ... | 2001 | 11765232 |
| use of the bead beater for preparation of mycobacterium paratuberculosis template dna in milk. | mycobacterium paratuberculosis is a recognized chronic enteric pathogen that can affect many different species of animals, including primates. it has been suggested that this organism is associated with crohn's disease in humans, and that milk is a potential source of human exposure to this organism. the limit of the detection of m. paratuberculosis in milk samples by direct pcr was 10(5) cfu/ml if the traditional boiling method was used for template dna preparation. in this study, an improved m ... | 2001 | 11768125 |
| crohn's disease and mycobacterium avium subsp. paratuberculosis: current issues. | crohn's disease is a chronic debilitating inflammatory bowel disease of unknown etiology. proposed causes include bacterial or viral infection, diet or exposure to tobacco smoke, genetic abnormality, and immune dysfunction. the bacterium mycobacterium avium subsp. paratuberculosis (map) has received much research attention as a potential cause of the disease. map causes johne's disease in ruminants. the pathology of johne's disease superficially resembles that of crohn's disease in humans. some ... | 2001 | 11770646 |
| quantitative analysis of mycobacterial and propionibacterial dna in lymph nodes of japanese and european patients with sarcoidosis. | the cause(s) of sarcoidosis is unknown. mycobacterium spp. are suspected in europe and propionibacterium spp. are suspected in japan. the present international collaboration evaluated the possible etiological links between sarcoidosis and the suspected bacterial species. formalin-fixed and paraffin-embedded sections of biopsy samples of lymph nodes, one from each of 108 patients with sarcoidosis and 65 patients with tuberculosis, together with 86 control samples, were collected from two institut ... | 2002 | 11773116 |
| comparison of real-time, quantitative pcr with molecular beacons to nested pcr and culture methods for detection of mycobacterium avium subsp. paratuberculosis in bovine fecal samples. | an automated pcr with fluorescent probes (molecular beacons) detected mycobacterium avium subsp. paratuberculosis in bovine feces. when the pcr was compared with culture in testing 41 fecal samples, kappa scores of 0.94 to 0.96, a sensitivity of 93 to 96%, and a specificity of 92% were obtained. results were quantitated by using a standard curve derived from a plasmid containing is900. a minimum quantity of 1.7 x 10(-4) pg of dna, correlating to 1 to 8 cfu, was detected. | 2002 | 11773135 |
| isolation of mycobacterium avium subsp paratuberculosis from the semen of rams with clinical johne's disease. | | 2001 | 11789915 |
| crohn's disease caused by mycobacterium avium subspecies paratuberculosis: a public health tragedy whose resolution is long overdue. | | 2002 | 11800469 |
| effect of commercial-scale high-temperature, short-time pasteurization on the viability of mycobacterium paratuberculosis in naturally infected cows' milk. | raw cows' milk naturally infected with mycobacterium paratuberculosis was pasteurized with an apv hxp commercial-scale pasteurizer (capacity 2,000 liters/h) on 12 separate occasions. on each processing occasion, milk was subjected to four different pasteurization treatments, viz., 73 degrees c for 15 s or 25 s with and without prior homogenization (2,500 lb/in(2) in two stages), in an apv manton gaulin kf6 homogenizer. raw and pasteurized milk samples were tested for m. paratuberculosis by immun ... | 2002 | 11823197 |
| maximum-likelihood estimation of sensitivity and specificity of elisas and faecal culture for diagnosis of paratuberculosis. | the accuracy of three diagnostic tests for paratuberculosis was evaluated using maximum-likelihood estimation of sensitivity and specificity. we also explored the variety of estimates that can be obtained if the tests are to be used in populations of different composition with regard to infection and disease states. two enzyme-linked immunosorbent assays (elisas) were evaluated separately with the faecal culture (fc). the study was carried out as a cross-sectional field study to cover all likely ... | 2002 | 11830293 |
| mycobacterium paratuberculosis and the bovine immune system. | mycobacterium avium subspecies paratuberculosis (m. paratuberculosis) is the causative agent of johne's disease, a deadly intestinal ailment of ruminants. johne's disease is of tremendous economic importance to the worldwide dairy industry, causing major losses due to reduced production and early culling of animals. a highly controversial but developing link between exposure to m. paratuberculosis and human crohn's disease in some individuals has led to the suggestion that m. paratuberculosis is ... | 2001 | 11831436 |
| sensitivity and specificity of pooled faecal culture and serology as flock-screening tests for detection of ovine paratuberculosis in australia. | the flock-level sensitivity of pooled faecal culture and serological testing using agid for the detection of ovine johne's disease-infected flocks were estimated using non-gold-standard methods. the two tests were compared in an extensive field trial in 296 flocks in new south wales during 1998. in each flock, a sample of sheep was selected and tested for ovine johne's disease using both the agid and pooled faecal culture. the flock-specificity of pooled faecal culture also was estimated from re ... | 2002 | 11849717 |
| killing of mycobacterium avium subspecies paratuberculosis within macrophages. | mycobacterium avium subspecies paratuberculosis (m. paratuberculosis) is a facultative intracellular pathogen that resides within host macrophages during infection of ruminant animals. we examined survival of m. paratuberculosis infections within cultured macrophages to better understand the interplay between bacterium and host. | 2002 | 11860602 |
| economic aspects of disease monitoring with special reference to bovine paratuberculosis. | monte carlo simulation models were used to evaluate the feasibility and potential results of a proposed national survey of the prevalence of bovine paratuberculosis (ptb) in dairy herds in norway. the expected herd prevalence was assumed to be 0.2% in the simulations. infected herds were classified as detected if 1 animal was sero-positive. with a sample size of 6000 herds at least 1 truly infected herd was detected in 99% of the iterations. the low sensitivity of the elisa test, the assumed low ... | 2001 | 11875849 |
| evaluation of the long-term immune response in cattle after vaccination against paratuberculosis in two dutch dairy herds. | in the past decades, vaccination against paratuberculosis in cattle was performed in the netherlands only on a limited scale. because of its interference with the diagnosis of bovine tuberculosis, vaccination was restricted to herds with a high prevalence of clinical cases of paratuberculosis and was meant to aid in the economical survival of the farm. recently, a voluntary paratuberculosis certification program has started, based in part on serological screening of cattle of at least 3 years of ... | 2002 | 11900960 |
| cell sorting of formalin-treated pathogenic mycobacterium paratuberculosis expressing gfp. | gfp is widely used as a molecular tool for the study of microbial pathogens. however, the manipulation of these pathogenic microorganisms poses a health threat to the laboratory worker, requiring biosafety level ii or iii containment. although the gfpfluorophore is tolerant toformalin, a thorough analysis of this treatment on fluorescent output in prokaryotic systems has not been described. in addition, the analysis of microorganisms expressing gfp often depends on specialized equipment, which m ... | 2002 | 11911654 |
| paratuberculosis with special reference to cattle. a review. | paratuberculosis is a chronic, granulomatous enteritis caused by mycobacterium avium subspecies paratuberculosis affecting domestic and wild ruminants. the symptoms of clinical paratuberculosis are chronic diarrhoea and progressive weight loss while subclinically infected animals mainly have decreased production. the infection is widespread throughout the world and causes substantial financial losses for the farming industry. one of the major obstacles in the control of this disease, is the diff ... | 2002 | 11918176 |
| genome scale comparison of mycobacterium avium subsp. paratuberculosis with mycobacterium avium subsp. avium reveals potential diagnostic sequences. | the genetic similarity between mycobacterium avium subsp. paratuberculosis and other mycobacterial species has confounded the development of m. avium subsp. paratuberculosis-specific diagnostic reagents. random shotgun sequencing of the m. avium subsp. paratuberculosis genome in our laboratories has shown >98% sequence identity with mycobacterium avium subsp. avium in some regions. however, an in silico comparison of the largest annotated m. avium subsp. paratuberculosis contigs, totaling 2,658, ... | 2002 | 11923349 |
| treatment of severe crohn's disease using antimycobacterial triple therapy--approaching a cure? | mycobacterium avium subspecies paratuberculosis is probably the best candidate for a microbial cause of crohn's disease although arguments to the contrary can be equally convincing. growing evidence suggests that prolonged antimycobacterial combination therapy can improve crohn's disease in some patients. | 2002 | 11926571 |
| treatment with drugs active against mycobacterium avium subspecies paratuberculosis can heal crohn's disease: more evidence for a neglected public health tragedy. | | 2002 | 11926580 |
| open clinical trial of rifabutin and clarithromycin therapy in crohn's disease. | crohn's disease, an inflammatory bowel disease in humans, has a suspected aetiology of mycobacterium avium subsp. paratuberculosis. | 2002 | 11930899 |
| development and application of quantitative polymerase chain reaction assay based on the abi 7700 system (taqman) for detection and quantification of mycobacterium avium subsp. paratuberculosis. | numerous reports have described diagnostic methods based on the polymerase chain reaction (pcr) used to detect mycobacterium avium subsp. paratuberculosis, the causative agent of johne's disease. the result of conventional pcr tests has been only qualitative, either positive or negative; it does not present any quantitative information about the number of the agents in the specimen. a quantitative pcr method (is900 taqman) was developed to measure the number of m. a. paratuberculosis organisms p ... | 2002 | 11939333 |
| relationships between fecal culture, elisa, and bulk tank milk test results for johne's disease in us dairy herds. | objectives were to estimate percentages of seropositive herds with cows shedding mycobacterium paratuberculosis in feces and milk, and to estimate sensitivity, specificity, and predictive value of an elisa relative to fecal culture. dairy cows (n = 712) were randomly selected from 61 herds previously identified by elisa as positive for johne's disease. fecal and bulk tank milk samples (n = 52 of 61 herds) were obtained from 10 states in the united states. fecal samples were processed by a double ... | 2002 | 11949855 |
| fibronectin attachment protein is necessary for efficient attachment and invasion of epithelial cells by mycobacterium avium subsp. paratuberculosis. | attachment and ingestion of mycobacterium avium subsp. paratuberculosis by two epithelial cell lines were enhanced by soluble fibronectin (fn). peptide blocking of the fn attachment protein (fap-p) inhibited the internalization of m. avium subsp. paratuberculosis. disruption of fap-p expression significantly reduced attachment and ingestion of m. avium subsp. paratuberculosis by t-24 and caco-2 cells. the results indicate that the interaction between fn and fap-p facilitates attachment and inter ... | 2002 | 11953410 |
| incidence of mycobacterium paratuberculosis in bulk raw and commercially pasteurized cows' milk from approved dairy processing establishments in the united kingdom. | over a 17-month period (march 1999 to july 2000), a total of 814 cows' milk samples, 244 bulk raw and 567 commercially pasteurized (228 whole, 179 semi-skim, and 160 skim), from 241 approved dairy processing establishments throughout the united kingdom were tested for the presence of mycobacterium paratuberculosis by immunomagnetic pcr (to detect all cells living and dead) and culture (to detect viable cells). overall, m. paratuberculosis dna was detected by immunomagnetic pcr in 19 (7.8%; 95% c ... | 2002 | 11976118 |
| application of the c(18)-carboxypropylbetaine specimen processing method to recovery of mycobacterium avium subsp. paratuberculosis from ruminant tissue specimens. | the causative agent of johne's disease is mycobacterium avium subsp. paratuberculosis. this is a chronic, debilitating gastrointestinal disorder that affects ruminants and is responsible for significant economic loss. the specimen processing method that combines c(18)-carboxypropylbetaine (cb-18) treatment and lytic enzyme decontamination has been shown to improve the diagnosis of mycobacterioses. this processing method was applied to the isolation of m. avium subsp. paratuberculosis from rumina ... | 2002 | 11980960 |
| molecular characterization of pigmented and nonpigmented isolates of mycobacterium avium subsp. paratuberculosis. | five pigmented isolates of mycobacterium avium subsp. paratuberculosis were examined by pulsed-field gel electrophoresis (pfge), is900 restriction fragment length polymorphism (is900-rflp), and is1311 polymorphism analysis using pcr. all of the pigmented isolates exhibited one of three distinct pfge profiles with snabi, designated 9, 10, and 11, and with spei, designated 7, 8, and 9, which generated three multiplex profiles designated [9-7], [10-8], and [11-9]. all of the pigmented isolates had ... | 2002 | 11980962 |
| infection and disease caused by environmental mycobacteria. | many species of mycobacteria that normally live as environmental saprophytes, the environmental mycobacteria (em), are opportunist causes of disease in humans and animals. many, but not all, cases are associated with some form of immune deficiency. an increasing number of species and clinical presentations are being described, and advances are being made in the understanding of the underlying predisposing factors. in recent years, four aspects of em disease have become particularly relevant to h ... | 2002 | 11981303 |
| synthesis and biological evaluation of new citrate-based siderophores as potential probes for the mechanism of iron uptake in mycobacteria. | several iron chelators containing alpha,beta-unsaturated hydroxamic acid motifs appended to a citric acid platform were synthesized. mycobacterium paratuberculosis was then challenged to grow in the presence of a panel of siderophores (mycobactin j, deferrioxamine b, acinetoferrin, and nannochelin a) and the new synthetic agents. of the structures tested, those containing the trans 2-octenoyl motif were preferred over those with trans cinnamoyl groups. in addition, derivatives containing longer ... | 2002 | 11985473 |
| the immunogenicity of mycobacterium paratuberculosis 85b antigen. | mycobacterium paratuberculosis (mpt) is the etiological agent of paratuberculosis. the disease is prevalent throughout the world, and exacts a heavy financial toll. at present, the only means of controlling this disease are culling or vaccination. the existing vaccines are not very efficient and produce a long-lasting local reaction at the point of injection and induce anti-bodies/delayed-type hypersensitivity (dth) reaction that cannot be differentiated from those of naturally infected animals. ... | 2002 | 12005331 |
| in situ identification of mycobacteria in crohn's disease patient tissue using confocal scanning laser microscopy. | the diversity in the methodology employed to investigate crohn's disease (cd) etiology has added significantly to the controversy of the mycobacterial role in this chronic inflammatory bowel disease. mycobacterium avium subsp paratuberculosis (map), a proposed and suspected agent in many cd patients, is a fastidious and very slow grower bacillus, which causes johne's disease (jd) in cattle. the methodology that has been widely and successfully used for isolation and identification of map from an ... | 2002 | 12005446 |
| an is900-like sequence found in a mycobacterium sp. other than mycobacterium avium subsp. paratuberculosis. | the insertion sequence is900 has been considered specific for mycobacterium avium subsp. paratuberculosis (m. paratuberculosis) and has, therefore, been used as the target gene for diagnostic pcr of m. paratuberculosis. from a healthy dairy cow we have isolated and characterised a mycobacterium harbouring one copy of a sequence with 94% identity to is900 at the nucleic acid level. the isolate was shown to be related to mycobacterium cookii, as assessed by 16s rrna sequencing. strong amplificatio ... | 2002 | 12007816 |
| diagnosis of paratuberculosis in naturally infected goats. | a survey was carried out to verify if an immunohistochemical method associated with agar gel immunodiffusion (agid) will establish a firm diagnosis of caprine paratuberculosis. one hundred and thirty-six goats were tested by agid for antibodies against mycobacterium avium subsp. paratuberculosis at two different times: the first time 22 (19.1%) were positive and the second time 25 (18%). one seronegative goat with severe diarrhea and 5 seropositive goats, two of which showing similar clinical si ... | 2002 | 12019718 |
| evaluation of two absorbed enzyme-linked immunosorbent assays and a complement fixation test as replacements for fecal culture in the detection of cows shedding mycobacterium avium subspecies paratuberculosis. | control of paratuberculosis in dairy herds is based on preventing the transmission of mycobacterium avium subsp. paratuberculosis (mptb) from cows to calves by management measures, supported by removal of cows excreting these bacteria by the fecal route (mptb shedders). fecal culture is the most accurate test for identifying mptb shedders, but this technique is expensive and takes up to 16 weeks for results to be available. serologic tests are inexpensive, rapid, and easy to perform. of serologi ... | 2002 | 12033677 |
| a fluorescence polarization assay for the detection of antibodies to mycobacterium bovis in cattle sera. | a fluorescence polarization assay (fpa) utilizing fluorescein-labelled mpb70 protein as the antigen was developed and evaluated for its ability to detect antibodies to mycobacterium bovis in cattle sera. three panels of sera were examined in this study. these included: (a) sera (n=28) obtained from cattle from which m. bovis was cultured; (b) sera (n=5666) from canadian field cattle which were presumed to be free from m. bovis; (c) sera (n=10) from cattle infected with mycobacterium paratubercul ... | 2002 | 12034543 |
| analysis of mitogen-stimulated lymphocyte subset proliferation and nitric oxide production by peripheral blood mononuclear cells of captive elk (cervus elaphus). | elk (cervus claphus) are reservoirs for brucella abortus, mycobacterium bovis, and mycobacterium avium subsp. paratuberculosis, each a serious pathogen of domestic livestock. an understanding of the basic immune responsiveness of elk would aid efforts to develop methods to diagnose and prevent these diseases of elk. peripheral blood mononuclear cells (pbmc) isolated from captive elk were examined for phenotype, lymphocyte subset proliferative capacity, and ability to produce nitric oxide (no) up ... | 2002 | 12038134 |
| survey of johne's disease in imported animals in the republic of ireland. | | 2002 | 12046789 |
| assessment of test results when using a commercial enzyme-linked immunosorbent assay for diagnosis of paratuberculosis in repeated samples collected from adult dairy cattle. | to determine the proportion of adult cattle that change test status when an elisa for antibodies against mycobacterium avium subsp paratuberculosis (map) is used to assay samples collected twice at variable intervals and to determine whether cows with an initial strong positive result were more likely to maintain positive status, compared with all cows with an initial positive result. | 2002 | 12051511 |
| the mycobacterium avium subsp. paratuberculosis elisa response by parity and stage of lactation. | two cross-sectional studies were carried out to determine the enzyme-linked immunosorbent assay (elisa) response to mycobacterium avium subsp. paratuberculosis (map) by cow characteristics and stage of lactation. one of the studies (referred to as "milk-group") used milk samples from all lactating cows (n=7994) in 108 danish dairy herds. the other study (referred to as "serum-group") used serum samples collected from all cows (n=5323) in a subset of 72 herds from the 108 herds. these samples wer ... | 2002 | 12062515 |
| progressive bovine paratuberculosis is associated with local loss of cd4(+) t cells, increased frequency of gamma delta t cells, and related changes in t-cell function. | bovine paratuberculosis is caused by the infection of young calves with mycobacterium avium subsp. paratuberculosis, resulting in a chronic granulomatous infection of predominantly the ileum. after an incubation period of 2 to 5 years, the disease becomes progressive in some of the chronically infected, but asymptomatic cows. this results in a protein-losing enteropathy that will ultimately be fatal. a loss of cell-mediated immune responses in symptomatic animals has been described, but no infor ... | 2002 | 12065529 |
| detection of mycobacterium avium subsp. paratuberculosis by buoyant density centrifugation, sequence capture pcr and dot blot hybridisation. | detection of mycobacterium avium subsp. paratuberculosis (m. paratuberculosis) by polymerase chain reaction (pcr) is often hampered by the lack of efficient methods for sample treatment. we report a protocol for analysis of faecal samples based on buoyant density centrifugation in percoll and is900 sequence capture pcr combined with a dot blot assay for detection of low-grade infection of m. paratuberculosis. serial dilutions of m. paratuberculosis genomic dna and m. paratuberculosis bacteria we ... | 2002 | 12069770 |
| mycobacterium paratuberculosis heat shock protein 70 as a tool in control of paratuberculosis. | paratuberculosis in cattle is a chronic intestinal disease in which a distinctive cellular reactivity of a th1-type preceeds the phase in which antibody titers are easily detectable and the animal becomes clinically ill. during infection with mycobacterium avium ssp. paratuberculosis (m.a.p), a decrease in cd4 t-helper cells has been observed in the clinical phase. our ultimate aim is to elicit a cytotoxic reaction against infected macrophages, using recombinant hsp70 (rhsp70) of m.a.p. as a too ... | 2002 | 12072241 |
| ifn-gamma diagnostic tests in the context of bovine mycobacterial infections in belgium. | in countries where cattle tuberculosis caused by mycobacterium bovis (mbov) and paratuberculosis caused by mycobacterium avium subsp. paratuberculosis (mptb) are present, testing strategies for the mbov eradication have to discriminate between these two infections. present indirect tests are based on the analysis of the specific cellular immune response (dth, ifn-gamma) against crude mycobacterial antigens (avian and bovine ppd). in this study, we compared the evolution of the ifn-gamma response ... | 2002 | 12072265 |
| survival tactics of m. paratuberculosis in bovine macrophage cells. | mycobacterium paratuberculosis (m. paratuberculosis) is a facultative intracellular bacterium with the ability to survive and proliferate inside the vesicles of macrophage cells. how m. paratuberculosis and other mycobacteria survive in this hostile environment is not well understood. present research findings can be divided into three possibilities: (1) mycobacteria may interfere with host protein expression and trafficking to stop vesicle maturation, (2) mycobacteria may express proteins that ... | 2002 | 12072269 |
| [establishment and evaluation of an elisa for the detection of antibodies in milk against mycobacterium avium subspecies paratuberculosis]. | mycobacterium avium ssp. paratuberculosis (m. paratuberculosis) is the etiological agent of paratuberculosis (johne's disease), a chronic granulomatous enteritis of ruminants occurring worldwide with increasing frequency and leading to growing economic losses. continuous surveillance of dairy farms would be advisable, particularly with respect to the increasing economic importance of paratuberculosis and the high tenacity of the pathogen, which can persist in the environment for many months. so ... | 2002 | 12073496 |
| pasteurization of milk and the heat resistance of mycobacterium avium subsp. paratuberculosis: a critical review of the data. | mycobacterium avium subsp. paratuberculosis (m. paratuberculosis) causes johne's disease in ruminants (including cattle, sheep and goats) and other animals, and may contribute to crohn's disease in humans. this possibility, and the fact that m. paratuberculosis may be present in raw milk, make it important to ensure that the heat treatment specified for pasteurization of milk will give acceptable inactivation of this bacterium, with an adequate margin of safety. published studies of the heat res ... | 2002 | 12076031 |
| application of is900 pcr for detection of mycobacterium avium subsp. paratuberculosis directly from raw milk. | a polymerase chain reaction (pcr)-based assay was developed for detection of insertion sequence 900 (is900) of mycobacterium avium subsp. paratuberculosis in raw milk. this is900 pcr assay included dna extraction and pcr assay using commercially available kits. the dna extraction and pcr assay were optimized to detect the is900 sequence directly from raw milk. the is900 pcr assay was evaluated by inoculating raw bulk milk and middlebrook's 7h9 broth with 0 to 10(8) cfu/ml of each of four america ... | 2002 | 12086038 |
| mycobacterium avium subsp. paratuberculosis infection in a patient with hiv, germany. | mycobacterium avium subsp. paratuberculosis (map), the causative agent of johne disease in ruminants, has been incriminated as the cause of crohn disease in humans. we report the first case of human infection with map in a patient with hiv; infection was confirmed by obtaining isolates from several different specimen types. | 2002 | 12095444 |
| detection of mycobacterium avium subspecies paratuberculosis specific is900 insertion sequences in bulk-tank milk samples obtained from different regions throughout switzerland. | since mycobacterium avium subspecies paratuberculosis (map) was isolated from intestinal tissue of a human patient suffering crohn's disease, a controversial discussion exists whether map have a role in the etiology of crohn's disease or not. raw milk may be a potential vehicle for the transmission of map to human population. in a previous paper, we have demonstrated that map are found in raw milk samples obtained from a defined region in switzerland. the aim of this work is to collect data abou ... | 2002 | 12097144 |
| survey of mycobacterium avium subspecies paratuberculosis serological status in beef herds on community pastures in saskatchewan. | johne's disease is a well recognized problem in dairy herds. relatively little information is available on either the prevalence or the control of johne's disease in commercial cow-calf operations. in the fall of 1999, blood samples were collected during pregnancy testing from cows on community pastures in saskatchewan. sera from these cows were analyzed using a commercial elisa for antibodies to mycoplasma avium subspecies paratuberculosis. all cows from each herd examined at the community past ... | 2002 | 12125186 |