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elevated antibody responses in patients with crohn's disease against a 14-kda secreted protein purified from mycobacterium avium subsp. paratuberculosis.patients with crohn's disease (cd) (n = 10) and ulcerative colitis (uc) (n = 10) were tested for immune responses against various antigens from mycobacterium avium subsp. paratuberculosis; alkyl hydroperoxide reductase c (ahpc) and alkyl hydroperoxide reductase d (ahpd), which are constitutively expressed in this species as opposed to other mycobacteria, a 14-kda secreted antigen and ppd-j. the cd patients had significantly elevated antibody levels against the 14 kda protein (p < 0.05) that were ...200111169225
use of short-term culture for identification of mycobacterium avium subsp. paratuberculosis in tissue from crohn's disease patients.to investigate the role of mycobacterium avium subsp. paratuberculosis (map) in crohn's disease (cd), using short-term mycobacterial culture media.200011168138
paratuberculosis in sheep: its possible role in the epidemiology of paratuberculosis in cattle.a total of 50 sheep originating from 15 dutch farms with a known paratuberculosis infection in their cattle herd, but with no history of paratuberculosis infection in their sheep flock, were examined for infection with mycobacterium avium subsp. paratuberculosis (map). the sheep had been grazing on the same pastures as the cattle or on pastures fertilised with manure from these cows. the sheep were screened for paratuberculosis by serum biochemistry, serology and intradermal skin tests. at necro ...200111163701
regulation of expression of major histocompatibility antigens by bovine macrophages infected with mycobacterium avium subsp. paratuberculosis or mycobacterium avium subsp. avium.mycobacterium avium subsp. paratuberculosis and mycobacterium avium subsp. avium are antigenically and genetically very similar organisms; however, they differ markedly in their virulence for cattle. we evaluated the capacity of bovine macrophages infected with m. avium subsp. paratuberculosis or m. avium subsp. avium to express major histocompatibility complex (mhc) class i and class ii antigens on their surface and to interact with primed autologous lymphocytes. our results indicate that infec ...200111159996
looking for mycobacterium paratuberculosis dna by polymerase chain reaction (pcr) in orofacial granulomatosis (ofg) and oral crohn's disease tissue in an irish population. 200011142959
modulation of gammadelta t cells and cd1 in mycobacterium avium subsp. paratuberculosis infection.m.a. paratuberculosis is the causal agent of paratuberculosis (johne's disease). recent work has suggested that gammadelta t cells may play an important role in the early immunological response to mycobacterial diseases, and that cd1 may act as a non-classical mhc molecule in antigen presentation to these gammadelta t cells. experimental infection of neonatal lambs with m.a. paratuberculosis was used to investigate the changes in gammadelta t cells and cd1 molecules in the gut associated lymphoi ...200011137128
in situ hybridization method for studies of cell wall deficient m. paratuberculosis in tissue samples.cell wall deficient forms of mycobacteria may be important in the pathogenesis of crohn's disease and sarcoidosis. however, no method has been available to localize this type of organisms in tissue sections. we developed an in situ hybridization method for the demonstration of mycobacterium paratuberculosis spheroplasts (cell wall deficient forms) in paraffin embedded tissue sections.m. paratuberculosis spheroplasts were prepared by treatment with glycine and lysozyme. pieces of beef were inject ...200011118736
pathogenesis and therapeutic aspects of crohn's disease.crohn's disease is a chronic, relapsing inflammatory condition affecting any part of the human gastrointestinal tract. it is characterised by transmural inflammation with deep ulceration, thickening of the bowel wall and fistula formation. the hallmark is the non-caseating granuloma. clinical presentation depends upon the site of the inflammation. pain and diarrhoea are frequent. extraintestinal manifestations develop in up to 25% of patients and perianal disease is also frequent. the aetiology ...200011118735
specific seroreactivity of crohn's disease patients against p35 and p36 antigens of m. avium subsp. paratuberculosis.crohn's disease (cd) is a chronic inflammatory bowel disease that is similar to johne's disease in ruminants. recent data have strengthened the association of m. avium subsp. paratuberculosis (m. paratuberculosis) with cd. to provide more evidence of an etiological association, antibody reactivities from cd patients were tested by immunoblotting against recombinant antigens that were identified previously from our m. paratuberculosis genomic library. two clones (designated pmptb#40 (3.2-kb inser ...200011118734
lewis rats are not susceptible to oral infection with mycobacterium avium subsp. paratuberculosis.pathogenesis studies of mycobacterium avium subsp. paratuberculosis infection in ruminants are hampered by the long incubation time of the disease. a laboratory animal model with a shorter incubation time would facilitate research in this field. although small rodents are usually considered to be resistant to m.a. paratuberculosis infection, several susceptible murine strains have been found. to our knowledge, there are no detailed reports with regard to susceptibility in rats. the lewis rat is ...200011118733
differences in the immune responses in lambs and kids vaccinated against paratuberculosis, according to the age of vaccination.in order to evaluate and compare the peripheral immune responses induced by the vaccination against paratuberculosis in relation with the age of immunization, two groups of lambs and goat kids were vaccinated at 15 days and 5 months old, respectively. a heat-killed commercial vaccine was inoculated subcutaneously and humoral and cellular immune responses were measured by an elisa and ifn-gamma assay, respectively, at 0, 30, 90, 180, 270 and 360 dpv in the lambs and 0, 30, 90 and 180 dpv in the c ...200011118732
transitions in immune responses to mycobacterium paratuberculosis.the host immune response to infection with mycobacterium paratuberculosis is paradoxical, with strong cell-mediated immune responses during the early, subclinical stages of infection and strong humoral responses during the late clinical stages of the disease. cell-mediated immune responses modulated by various t cell subsets are essential to provide protective immunity and prevent progression of the disease. secretion of cytokines by t cell populations serves to activate macrophages to kill inge ...200011118731
further studies on the gs element. a novel mycobacterial insertion sequence (is1612), inserted into an acetylase gene (mpa) in mycobacterium avium subsp. silvaticum but not in mycobacterium avium subsp. paratuberculosis.we have recently described the gs element, found in mycobacterium avium subsp. paratuberculosis (map), mycobacterium avium subsp. silvaticum (mas) and some isolates of mycobacterium avium subsp. avium serotype 2 (maas2), which contains a set of genes of low gc% content, putatively associated with the biosynthesis, modification and transference of fucose to cell wall glycopeptidolipids. here we describe a further gene of low gc% content (mpa), within the gs element in map. mpa is a putative acety ...200011118730
progress in national control and assurance programs for bovine johne's disease in australia.cattle strains of mycobacterium paratuberculosis are known to infect cattle, goats and alpaca in southeastern australia, where there are also significant numbers of farmed deer. although sheep strains have recently been identified in some cattle in australia, epidemiological evidence to date supports the distinction (between bovine johne's disease (jd), caused by cattle strains in cattle, goats and alpaca, and ovine jd, caused by sheep strains in sheep and goats) for the purposes of control and ...200011118729
herd testing to control bovine johne's disease.in 1996, the cattle industries and government in the australian state of victoria established a johne's disease (jd) test and control program under which participating farmers are provided with an annual elisa test of their adult herd and advice on disease control that is tailored to their farm. the program is delivered through private veterinarians under contract with the government. there are over 600 herds enrolled in the program and about one third of these have had three or more whole herd ...200011118727
progress in national control and assurance programs for ovine johne's disease in australia.since the detection of ovine johne's disease in australia in 1980, 578 flocks have been diagnosed as infected, with 442 of these still infected. the disease was initially believed to be confined to the central tablelands area of nsw, but has subsequently been shown to be more widely distributed. sheep strains of m. paratuberculosis are known to infect sheep and goats in south-eastern australia. although sheep strains have recently been identified in some cattle in australia, epidemiological evid ...200011118726
elisa and fecal culture for paratuberculosis (johne's disease): sensitivity and specificity of each method.the sensitivity and specificity of the elisa and fecal culture tests for paratuberculosis in dairy cattle are examined. elisa and fecal culture data from seven dairy herds where both fecal cultures and elisa testing was done concurrently are included. a cohort of 954 cattle including 697 parturient adults, cultured every 6 months from 10 herds followed over 4 years served as the basis to determine fecal culture sensitivity. the fecal culture technique utilized a 2g sample with centrifugation and ...200011118724
use of a pcr method on fecal samples for diagnosis of sheep paratuberculosis.the high sensitivity of pcr compared to the difficulties of fecal culture in sheep prompted the development of pcr protocols for detection of mycobacterium avium subsp. paratuberculosis dna in sheep feces. although the pcr itself is well developed, and does not pose large technical problems, concentrating the bacteria from samples that may contain low numbers of bacilli using practical methods is still the main difficulty for the use of this technique. in this study, we describe an extraction pr ...200011118723
improved detection of mycobacterium avium subsp. paratuberculosis in milk by immunomagnetic pcr.the potential use of a novel immunomagnetic pcr (ims-pcr) technique as a rapid method to screen milk samples for the presence of mycobacterium avium subsp. paratuberculosis (m. ptb) was assessed. immunomagnetic separation (ims) for m. ptb, developed at queen's university, belfast, was applied to milk samples prior to is900 pcr in order to selectively concentrate any m. ptb cells present and, at the same time, separate the cells from constituents of milk likely to inhibit subsequent pcr. this inc ...200011118722
comparative sensitivity of various faecal culture methods and elisa in dairy cattle herds with endemic johne's disease.in three new south wales dairy cattle herds with endemic johne's disease, prevalence rates by faecal culture were determined to be 12, 18 and 22%, respectively. whole herd faecal culture was shown to detect markedly more infected cattle than whole herd testing by the emai absorbed elisa, particularly in the two herds with greatest prevalence. in the three study herds, five methods for whole herd faecal culture were compared in each. these included two methods based on primary culture on herrold' ...200011118721
automation of an absorbed enzyme immunoassay for the detection of mycobacterium paratuberculosis antibodies for an eradication program.as part of an ongoing johne's disease eradication program by the state of victoria, australia, the victorian veterinary pathology services (vvps) has been involved in testing over 150000 cattle samples per year for the presence of johne's-specific antibodies. the parachek kit (csl, victoria, australia) has been used throughout the project. this method was automated using a rosys 3300 and a plato 7 (dade/behring diagnostics) to pipette samples and the behring elisa processor 3 (dade/behring diagn ...200011118720
mycobacterium avium subsp. paratuberculosis infection in cattle in austria, diagnosis with culture, pcr and elisa.serum samples from healthy, infected (n=11) and diseased (n=2) cattle as well as positive (n=17) and negative (n=41) reference sera were tested for antibodies to mycobacterium avium subsp. paratuberculosis with two elisa-methods (a-elisa, allied monitors, fayette, usa; h-elisa, institute of microbiology and animal diseases, veterinary university hannover). fecal samples of these animals were examined by pcr and culture. also field serum samples found to be positive (n=664) or inconclusive (n=158 ...200011118719
modification of a bovine elisa to detect camelid antibodies to mycobacterium paratuberculosis.mycobacterium avium subsp. paratuberculosis infection, or johne's disease, reportedly has a low prevalence in south american camelid populations. recently, however, single cases in the united states as well as an outbreak of the disease in australian alpacas (lama pacos) have been described. to provide a rapid and cost-effective method of diagnosing johne's disease in this species, the bovine parachek((r)) johne's absorbed eia (csl, vic., australia) was modified to create a camelid-specific seru ...200011118718
the histopathologic diagnosis of subclinical johne's disease in north american bison (bison bison).the morphologic changes of subclinical johne's disease in north american bison (bison bison) are characterized by microgranulomas composed of epithelioid macrophages and individual multinucleate giant cells of langhans'-type occasionally containing individual cytoplasmic acid-fast bacilli compatible with mycobacterium avium paratuberculosis. the microgranulomas are best visualized in the mesenteric lymph nodes of infected subclinical animals. macrophages that can be confused with infection-assoc ...200011118717
parallel faecal and organ mycobacterium avium subsp. paratuberculosis culture of different productivity types of cattle.faecal (at least 3 months before slaughtering) and organ examinations were carried out in 611 animals (497 dairy, 69 dual-purpose and 44 beef cattle) originating from eight paratuberculosis infected cattle herds. the diagnosis in cattle was established by routine intestinal culture (ileum and the adjacent lymph nodes) after slaughter. in selected 132 animals, post-mortem intensive culture was performed on tissue samples collected from the gastrointestinal tract (duodenum, jejunum, ileum, ileocec ...200011118716
paratuberculosis in sheep: an emerging disease in south africa.during a serological survey for ovine paratuberculosis a total of 145934 ovine serum samples from 2019 farms throughout south africa were tested by means of the agid assay. fifty-two infected farms were identified in the western cape and eastern cape provinces. links between infected farms in the two provinces were established. examination of the distribution of infected farms in the western cape indicated a positive correlation between acid soils and occurrence of infection. in an attempt to in ...200011118715
detection of mycobacterium avium subsp. paratuberculosis in milk from clinically affected cows by pcr and culture.milk and faeces samples from cows with clinical symptoms of paratuberculosis were examined for the presence of mycobacterium avium subsp. paratuberculosis (m. paratuberculosis) by culture and pcr. m. paratuberculosis was cultivated in variable numbers from faeces or intestinal mucosa in eight of 11 animals. in milk from five cows (all faeces culture positive), we cultivated a few colonies of m. paratuberculosis (<100 cfu per ml). milk samples from two cows were pcr positive (both animals were fa ...200011118714
first evidence of johne's disease in farmed red deer (cervus elaphus) in belgium.in a deer farm, chronic diarrhoea was seen in a 4-year-old hind. this animal died in poor condition on the farm and johne's disease was suspected. ziehl-neelsen staining of the faeces of this hind were positive for the presence of clumps of small acid-fast bacilli, but faecal cultures remained negative. direct and indirect tests were performed on 24 hinds and stags (yearlings, 2- and 4-year-old animals). the indirect tests performed were serology (mycobacterium paratuberculosis antibody elisa, h ...200011118713
prevalence of paratuberculosis (johne's disease) in the belgian cattle population.the national bovine paratuberculosis (ptb) seroprevalence (apparent prevalence) in the belgian cattle population was determined by a serological survey that was conducted from december 1997 to march 1998. in a random sample of herds (n=556, 9.5%), all adult cattle of 24 months of age or older (n=13,317, 0.4%) were tested for the presence of antibodies using a commercially available absorbed elisa test kit. the ptb median within-herd seroprevalence (proportion of detected animals within the serop ...200011118712
paratuberculosis in iceland: epidemiology and control measures, past and present.paratuberculosis as well as the slow virus infections maedi/visna and jaagsiekte came to iceland in 1933 when 20 sheep of the karakul breed were imported from halle, germany. at least five of these sheep were subclinical carriers of paratuberculosis. within 16 years paratuberculosis together with the other karakul diseases (maedi/visna and jaagsiekte) almost ruined sheep farming, the main agricultural industry in iceland. the first clinical case of paratuberculosis in sheep was confirmed in 1938 ...200011118711
prevalence and regional distribution of paratuberculosis in dairy herds in the netherlands.in the netherlands a survey was conducted to estimate the prevalence of paratuberculosis in dairy herds. in total 15822 cows of at least 3 years of age, belonging to 378 herds were tested using an absorbed elisa. of these herds, 55% (n=207) had one or more serologically positive cows. of the positive non-vaccinated herds, most had one (n=98) or two (n=49) positive cows. the percentage positive cows per herd was 2.5+/-3.2%.the true prevalences on cow and herd levels, based on a test sensitivity t ...200011118710
epidemiology of paratuberculosis in wild ruminants studied by restriction fragment length polymorphism in the czech republic during the period 1995-1998.in two studies carried out during the period 1995-1998, paratuberculosis was diagnosed in domestic and wild ruminants in the czech republic. the isolated mycobacterium avium subspecies paratuberculosis strains were analysed by standardised restriction fragment length polymorphism (rflp) [pavlik, i., horvathova, a., dvorska, l., bartl, j., svastova, p., du maine, r., rychlik, i., 1999. j. microbiol. methods 38, 155-167]. in december 1992, 19 late pregnant charolais heifers were imported to the cz ...200011118709
culture of strategically pooled bovine fecal samples as a method to screen herds for paratuberculosis.fecal samples from 733 cows in 11 dairy herds with a low prevalence of paratuberculosis were cultured for the presence of mycobacterium avium subsp. paratuberculosis both individually and after combining (pooling) in groups of 5. the culture procedure was the modified jorgensen method, which uses naoh and oxalic acid for decontamination and modified lowenstein-jensen agar slants for cultivation. pooling was performed by mixing fecal samples from 5 animals ordered by age, herein referred to as st ...200011108455
mycobacterium paratuberculosis infection in two free-ranging alpine ibex.the authors report two cases of mycobacterium paratuberculosis infection in free-ranging alpine ibex (capra ibex) from two different herds in the western alps, italy. one ibex, found dead in october 1998, was in poor condition. the second animal died due to trauma following capture with a dart gun. the only gross lesions observed were the enlargement of the mesenteric and iliac lymph nodes. samples from both ibex tested positive to polymerase chain reaction for a primer set specific for the m. p ...200011107630
[first description of concomitant infection with tuberculosis and paratuberculosis in dairy sheep in argentina].the authors present the results of a comparative intradermal tuberculin test performed on dairy sheep to determine rates of reaction to bovine and avian purified protein derivative (ppd). test reactions were interpreted by palpation and measurement with a calliper. results were analysed by plotting the values obtained. agar gel immunodiffusion tests, growth in culture and histopathological examinations were also performed to allow differential diagnosis between tuberculosis and paratuberculosis. ...200011107623
genetic variation of susceptibility to mycobacterium avium subsp. paratuberculosis infection in dairy cattle.paratuberculosis is an infectious disease that is not easily amenable to classical control methods such as treatment and vaccination. experimental animal models suggest that there could be genetic factors responsible for susceptibility or resistance to infection with the causative agent, mycobacterium avium subsp. paratuberculosis. the aim of this study was to estimate genetic variation in susceptibility to paratuberculosis in dutch dairy cattle. data collected during a vaccination trial, conduc ...200011104291
characterization of is900 loci in mycobacterium avium subsp. paratuberculosis and development of multiplex pcr typing 200011101687
distinct differences in repertoires of low-molecular-mass secreted antigens of mycobacterium avium complex and mycobacterium tuberculosis.antigens in a 4-week-old culture filtrate (cf) of mycobacterium avium subsp. avium were separated in sodium dodecyl sulfate-polyacrylamide gel electrophoresis and identified by western blotting. the culture had minimal lysis of bacilli, giving a cf preparation consisting mainly of secreted proteins. comparison with a similar cf of mycobacterium tuberculosis with almost no contamination with intracellular proteins showed the presence of cross-reactive antigens homologous to the four components of ...200011101579
results of multiple diagnostic tests for mycobacterium avium subsp. paratuberculosis in patients with inflammatory bowel disease and in controls.mycobacterium avium subsp. paratuberculosis has been incriminated as a cause of crohn's disease (cd); however, studies to date have been relatively small and generally only used a single diagnostic assay. the objective of the study was to reexamine the association of m. avium subsp. paratuberculosis and cd using multiple diagnostic tests. five methods were used to detect m. avium subsp. paratuberculosis infections in 439 inflammatory bowel disease (ibd) patients and 324 control subjects in the u ...200011101567
paratuberculosis recognized as a problem at last: a review.this article attempts to review briefly current opinions on johne's disease, or paratuberculosis, in ruminants caused by mycobacterium avium subsp. paratuberculosis. paratuberculosis has been known to be prevalent in domestic livestock, such as cattle, goats, and sheep, for more than a century. despite this knowledge only minor efforts have been made to control the disease and, with the attention being focussed on the eradication of other diseases, the problem of paratuberculosis has been neglec ...200011087130
paratuberculosis in red deer (cervus elaphus hippelaphus) in the western alps.during the hunting seasons 1995-96 to 1997-98, 19 red deer from the upper susa valley (cottian alps) were examined for paratuberculosis (johne's disease). specific dna amplification on mesenteric lymph nodes detected mycobacterium avium paratuberculosis in 17 animals. ten of these red deer were tested for serum antibodies by the agid and elisa tests, nine being negative. three isolates from infected deer were genetically characterized by an arbitrarily primed polymerase chain reaction, and showe ...200011085463
kinetics of il-2 receptor expression on lymphocyte subsets from goats infected with mycobacterium avium subsp. paratuberculosis after specific in vitro stimulation.quantification of surface il-2r expression on activated lymphocytes by flow cytometry have recently been reported to be useful in measuring cellular immunity against mycobacterium avium subsp. paratuberculosis in goats (whist et al., 2000, vet. immunol. immunopathol. 73, 207-218). to characterise the phenotype of the peripheral lymphocytes expressing il-2r after in vitro stimulation with purified protein derivative (ppd) from m. a. paratuberculosis, cells were processed for dual or triple colour ...200011068065
the pathology of spontaneous paratuberculosis in the north american bison (bison bison).gross and histopathologic examinations were performed on 70 north american bison (bison bison) from a mycobacterium avium paratuberculosis culture-positive herd. the bison examined were part of a breeding herd totaling 2,800 animals. eight of 70 (11%) animals had gross findings of intestinal mucosal thickening, and 16 of 70 (23%) of the animals had enlarged mesenteric lymph nodes. histologic lesions compatible with johne's disease were diagnosed in 30 of 70 (43%) bison on the basis of the demons ...200011055866
reduced formation of granulomata in gamma(delta) t cell knockout balb/c mice inoculated with mycobacterium avium subsp. paratuberculosis.the role of gamma(delta) t cells in the bovine immune response to mycobacterium avium subsp. paratuberculosis (m. paratuberculosis) infection is poorly understood. accordingly, using balb/c mice that are innately susceptible to m. paratuberculosis, we compared wild-type and gamma(delta) t cell knockout balb/c mice to study the protective roles of gamma(delta) t cells in m. paratuberculosis infection. ten-week-old mice were inoculated intraperitoneally with either a low dose (4 x 10(6) colony-for ...200011055864
biosecurity on dairy operations: hazards and risks.the objective here was to present a model for considering biosecurity related to infectious diseases on us dairy operations using a risk assessment framework. with the example of an important dairy cattle pathogen (mycobacterium paratuberculosis), i followed risk assessment steps to characterize risks related to the use of certain management practices and possible risk reduction within an infectious disease biosecurity program. biosecurity practices focus on the prevention of introduction of the ...200011049083
use of the polymerase chain reaction assay for the detection of mycobacterium avium subspecies paratuberculosis in blood and liver biopsies from experimentally infected sheep.to evaluate a polymerase chain reaction-based assay for the detection of mycobacterium avium subsp paratuberculosis in blood and liver biopsies from subclinically infected sheep.200011022290
identification of cell wall deficient forms of m. avium subsp. paratuberculosis in paraffin embedded tissues from animals with johne's disease by in situ hybridization.m. avium subsp. paratuberculosis (m. paratuberculosis) is the causative agent of johne's disease (jd) in ruminants leading to enormous economical losses in dairy and meat industries worldwide. during the subclinical stage of the disease, the infected animals are difficult if not impossible to detect by the available diagnostic tests including the pcr based ones. although only considered an animal pathogen, cell wall deficient (cwd) forms of m. paratuberculosis have been isolated from patients wi ...200011018275
hspx is present within mycobacterium paratuberculosis-infected macrophages and is recognized by sera from some infected cattle.a portion of the gene encoding hspx has been previously identified as a sequence specific to mycobacterium avium subspecies paratuberculosis (hereafter referred to as m. paratuberculosis) based on dna hybridization experiments. in this study, rabbit antisera were raised against a recombinant protein of hspx fused to the escherichia coli maltose binding protein (mbp/hspx). immunoblots of lysates of m. paratuberculosis-infected macrophages probed with the rabbit antisera showed that hspx was prese ...200011000531
presence of bacterial 16s ribosomal rna gene segments in human intestinal lymph follicles.there is currently no information regarding microbial agents inside the intestinal lymph follicles.200010994621
vaccination against paratuberculosis of lambs already infected experimentally with mycobacterium avium subspecies paratuberculosis.to assess the protective value of a live-attenuated vaccine in sheep already exposed to mycobacterium avium subsp paratuberculosis and to investigate the progression of a systemic immune response in experimentally infected sheep.200010979513
characterization of is900 loci in mycobacterium avium subsp. paratuberculosis and development of multiplex pcr typing.mycobacterium avium subsp. paratuberculosis is a pathogen that causes chronic inflammation of the intestine in many animals, including primates, and is implicated in crohn's disease in humans. it differs from other members of the m. avium complex in having 14-18 copies of is900 inserted into conserved loci in its genome. in the present study, genomic dna flanking 14 of these insertions was characterized and homologues in the mycobacterium tuberculosis and m. avium subsp. avium genomes were ident ...200010974106
heat resistance of mycobacterium paratuberculosis. 200010972725
quality control and optimized procedure of hybridization capture-pcr for the identification of mycobacterium avium subsp. paratuberculosis in faeces.nucleic acid sequence capture techniques are used to improve both the sensitivity and specificity of pcr for the diagnosis of plant, animal and human diseases. hybridization capture-pcr (hc-pcr) was first reported as a method for the detection of mycobacterium avium subsp. paratuberculosis in 1995 and was successfully trialed on a small number of faecal samples from cattle with johne's disease. a locally optimized hc-pcr method was evaluated on faeces from infected and non-infected animals. howe ...200010970726
molecular epidemiology of mycobacterium avium subsp. paratuberculosis: is900 restriction fragment length polymorphism and is1311 polymorphism analyses of isolates from animals and a human in australia.the distribution and prevalence of strains of mycobacterium avium subsp. paratuberculosis were determined among sheep, cattle, and other species with johne's disease in australia. a total of 328 isolates were evaluated from numerous farms in new south wales, victoria, tasmania, and south australia, australia. restriction fragment length polymorphism (rflp) analysis of genomic dna using bsteii and an is900 probe and is1311 polymorphism analysis using pcr and restriction endonuclease analysis (pcr ...200010970365
in situ-pcr for the detection of mycobacterium paratuberculosis dna in paraffin-embedded tissues.molecular biological techniques have permitted the rapid and sensitive detection of the mycobacterium paratuberculosis genome in infected tissues, most commonly by polymerase chain reaction amplification of sequences in the is900 dna insertion sequence. the aim of this work was the detection of m. paratuberculosis dna in ovine tissues by in situ-polymerase chain reaction, which is sensitive and localises the signal within the tissue sample. paraffin embedded tissues from three acid-fast positive ...200010968366
duplex pcr for differential identification of mycobacterium bovis, m. avium, and m. avium subsp. paratuberculosis in formalin- fixed paraffin-embedded tissues from cattle.we previously isolated and sequenced two genomic segments of mycobacterium avium subsp. paratuberculosis, namely, f57, a species-specific sequence, and the p34 gene, coding for a 34-kda antigenic protein. comparison of sequences upstream of the p34 open reading frame (us-p34) from m. avium subsp. paratuberculosis and m. tuberculosis showed a 79-base deletion in m. tuberculosis. sequence analysis of the p34 genes in another two species, m. bovis (strain bcg) and m. avium (strain d4), confirmed th ...200010921976
the effect of subclinical mycobacterium paratuberculosis infection on days open in michigan, usa, dairy cows.a prospective cohort study design was used to evaluate the impact of subclinical mycobacterium paratuberculosis infection on days open in a sample of michigan dairy herds with a history of cows positive for m. paratuberculosis diagnosed by fecal culture. participating herds were tested and productivity and reproduction records were monitored for 18 months. all cows > or = 24 months old were tested for m. paratuberculosis infection using the elisa and radiometric fecal-culture (rfc) techniques. t ...200010913802
biosecurity practices of beef cow-calf producers.to evaluate biosecurity practices of cow-calf producers.200010909456
johne's disease and milk: do consumers need to worry?mycobacterium paratuberculosis, an acid-fast bacillus that causes enteritis in ruminants, has been suggested as an etiological agent of crohn's disease in humans. the mode of transmission is unclear; however, some evidence suggests that humans may become infected via contaminated milk. currently, it is not known whether commercial pasteurization effectively kills m. paratuberculosis in contaminated raw milk. using a laboratory-scale pasteurizer unit designed to simulate the high-temperature, sho ...200010908069
specificity of four serologic assays for mycobacterium avium ss paratuberculosis in llamas and alpacas: a single herd study.an investigation was conducted for mycobacterium avium ss paratuberculosis infections in a research herd of llamas and alpacas. herd culture-negative status was established over a 23-month period by screening any individuals with any signs compatible with paratuberculosis (n = 1), high serology values (n = 8), or other health and research related reasons (n = 24). there were no m. avium ss paratuberculosis isolates from radiometric cultures of multiple tissue and fecal samples from these individ ...200010907864
cytokine secretion by peripheral blood mononuclear cells from cows infected with mycobacterium paratuberculosis.to compare cytokine secretion patterns of peripheral blood mononuclear cells (pbmc) from healthy cows and cows subclinically and clinically infected with mycobacterium paratuberculosis.200010895895
causation of crohn's disease by mycobacterium avium subspecies paratuberculosis.mycobacterium avium subspecies paratuberculosis (map) is a member of the m avium complex (mac). it differs genetically from other mac in having 14 to 18 copies of is900 and a single cassette of dna involved in the biosynthesis of surface carbohydrate. unlike other mac, map is a specific cause of chronic inflammation of the intestine in many animal species, including primates. the disease ranges from pluribacillary to paucimicrobial, with chronic granulomatous inflammation like leprosy in humans. ...200010888733
a causal role for mycobacterium avium subspecies paratuberculosis in crohn's disease? 200010888725
use of pooled fecal culture for sensitive and economic detection of mycobacterium avium subsp. paratuberculosis infection in flocks of sheep.ovine johne's disease, or paratuberculosis, occurs in many countries. in australia, surveillance using serology is used as part of a control program, but the testing regime is costly relative to its sensitivity. for this reason, culturing of mycobacterium avium subsp. paratuberculosis in fecal samples pooled from a number of sheep was evaluated. initially, the effect of pooling on the sensitivity of fecal culture was evaluated using samples from 20 sheep with multibacillary paratuberculosis and ...200010878042
evaluation of the accuracy and reproducibility of a practical pcr panel assay for rapid detection and differentiation of mycobacterium avium subspecies.the mycobacterium avium subspecies (mas) include the closely related mas avium and mas paratuberculosis. this study was conducted to evaluate the performance of a pcr panel assay as a diagnostic tool to detect and differentiate mas avium and mas paratuberculosis infection. specific oligonucleotides primers derived from the 16 s rrna (mas) sequence, insertion elements is 901 (mas avium), is 1245 mycobacterium avium complex (mac), is 900 (mas paratuberculosis), and the hspx (mas paratuberculosis) ...200010860713
dna fingerprinting of australian isolates of mycobacterium avium subsp paratuberculosis using is900 rflp.to evaluate additional restriction enzymes for is900 rflp of mycobacterium avium subsp paratuberculosis and examine the genetic diversity among australian isolates for epidemiological studies of johne's disease.200010860159
binding of bovine growth hormone to. mycobacterium avium ss paratuberculosis.mycobacterium avium ss paratuberculosis causes a chronic progressive enteritis in cattle and other ruminants referred to as johne's disease. it also has been suggested by some as possibly being associated with crohn's disease in humans. in a previous study we observed that incubation of bovine monocytes with recombinant bovine growth hormone (bgh) altered the ingestion and intracellular growth of m. avium ss paratuberculosis in vitro. this led us to investigate whether bgh also has a direct effe ...200010855661
a cross-sectional study of paratuberculosis in 1155 danish dairy cows.in a cross-sectional study on milk samples from 1155 cows from 22 danish dairy herds, selected risk factors for paratuberculosis were identified. the diagnostic procedure used was an indirect enzyme-linked immuno-sorbent assay (elisa) to detect antibodies against mycobacterium avium subsp. paratuberculosis. a sample was considered test-positive if it had a corrected optical density >/=0. 025 (test sensitivity 71.4% and test specificity 89.7%). of the 1155 samples, 8.8% (102/1155) were test-posit ...200010854933
detection of mycobacterium avium subsp paratuberculosis in formalin-fixed paraffin-embedded intestinal tissue by is900 polymerase chain reaction.to evaluate and compare methods for dna extraction from formalin-fixed, paraffin-embedded tissues and methods for detection of mycobacterium avium subsp paratuberculosis by is900 pcr for confirmation of johne's disease in ruminants.199910812407
herd-level risk factors for infection with mycobacterium paratuberculosis in us dairies and association between familiarity of the herd manager with the disease or prior diagnosis of the disease in that herd and use of preventive measures.to evaluate associations among herd infection status, herd management practices, and familiarity of the herd manager with mycobacterium paratuberculosis (johne's disease) or prior disease diagnosis in that herd to support development of johne's disease-control programs.200010800519
mycobacterium paratuberculosis heat resistance. 200010792659
isolation of mycobacterium avium subsp paratuberculosis from breast milk of crohn's disease patients. 200010763975
construction and screening of mycobacterium paratuberculosis insertional mutant libraries.mycobacterium paratuberculosis causes johne's disease, a common wasting disease in ruminants. as a first step in studying virulence mechanisms, libraries of random mutants were produced in two m. paratuberculosis strains by using the conditionally replicating shuttle phasmid phae94 which contains the transposon tn5367. two thousand mutants were screened for auxotrophy, carbon source preference, and altered cell wall. genes interrupted by insertion were identified for seven mutants isolated from ...200010763756
effect of three factors in cheese production (ph, salt, and heat) on mycobacterium avium subsp. paratuberculosis viability.low ph and salt are two factors contributing to the inactivation of bacterial pathogens during a 60-day curing period for cheese. the kinetics of inactivation for mycobacterium avium subsp. paratuberculosis strains atcc 19698 and dominic were measured at 20 degrees c under different ph and nacl conditions commonly used in processing cheese. the corresponding d values (decimal reduction times; the time required to kill 1 log(10) concentration of bacteria) were measured. also measured were the d v ...200010742208
temporal patterns and quantification of excretion of mycobacterium avium subsp paratuberculosis in sheep with johne's disease.to determine the frequency of excretion of mycobacterium avium subsp paratuberculosis in merino sheep with johne's disease and to quantify excretion in a group of merino sheep.200010736683
bulk-tank milk elisa antibodies for estimating the prevalence of paratuberculosis in danish dairy herds.paratuberculosis (johne's disease) has been widespread in danish dairy herds for a long time but the herd-level prevalence has never been determined precisely. to evaluate the prevalence of paratuberculosis in danish dairy herds in various regions, an elisa based on a commercially available antigen was adapted for testing bulk-tank milk for the presence of antibodies to mycobacterium avium subsp. paratuberculosis. bulk-tank milk samples were collected from six milk-collecting centres from six di ...200010727740
the use of interleukin-2 receptor expression as a marker of cell-mediated immunity in goats experimentally infected with mycobacterium avium ssp. paratuberculosis.the purpose of the present work was to demonstrate cell-mediated immune response to paratuberculosis in experimentally infected animals, using quantification of interleukin-2 receptor (il-2r) expression on activated lymphocytes by means of in vitro stimulation with mycobacterium avium ssp. paratuberculosis-derived purified protein derivative (ppdp). a whole-blood technique was developed, and optimal conditions for quantification of il-2r expression on caprine lymphocytes, using monoclonal antibo ...200010713335
immunohistochemical detection of mycobacterium paratuberculosis in formalin-fixed, paraffin-embedded bovine tissue sections. 200010690778
etiology and pathophysiology of inflammatory bowel disease--environmental factors.environmental factors play an important role in the pathophysiology of inflammatory bowel disease. there is a strong and consistent association between smoking and crohn's disease, and between nonsmoking and ulcerative colitis. despite extensive research, the exact pathophysiological mechanisms for these associations remain unclear. in spite of this, some clinical trials with nicotine-patches showed beneficial effects for the treatment of ulcerative colitis. associations of crohn's disease and u ...200010690583
use of macroporous polypropylene filter to allow identification of bacteria by pcr in human fecal samples.the detection of pathogenic bacteria directly in human fecal specimens by pcr, requires removal of pcr-inhibitory substances. to investigate whether five different macroporous filters (polypropylene, nylon, polyester, polyethylene, fluorocarbon) could retain polysaccharides, major pcr inhibitors, an in vitro model and human fecal samples were used. the in vitro model consisted of xanthum gum solutions (3 mg/ml pbs), a bacterial polysaccharide, to which helicobacter pylori cells were added. fecal ...200010670772
mycobacteria distenct from mycobacterium avium subsp. paratuberculosis isolated from the faeces of ruminants possess is900-like sequences detectable is900 polymerase chain reaction: implications for diagnosis.pcr targeting the 5' end of is 900 has been considered specific for identification of mycobacterium avium subsp. paratuberculosis and is frequently applied to confirm the presence of this organism in the diagnosis of johne's disease. is 900 pcr has also been applied to studies of the aetiology of crohn's disease. mycobacterium spp. isolated from the faeces of 3 clinically normal animals in 2 australian states appeared not to be m. paratuberculosis but were positive by is 900 pcr. the isolates we ...199910657148
alkyl hydroperoxide reductases c and d are major antigens constitutively expressed by mycobacterium avium subsp. paratuberculosis.antigens characteristic for mycobacterium avium subspecies paratuberculosis were identified by crossed immunoelectrophoresis (cie) and by absorbing out cross-reactive antigens by using a polyclonal and polyvalent mycobacterium avium subspecies avium antiserum. two antigens were present in m. avium subsp. paratuberculosis and not detected in mycobacterium avium subsp. avium. they were identified as antigens 17 and 20 in a cie reference system for m. avium subsp. paratuberculosis antigens. purifie ...200010639449
distribution of is900 restriction fragment length polymorphism types among animal mycobacterium avium subsp. paratuberculosis isolates from argentina and europe.sixty-one mycobacterium avium subsp. paratuberculosis isolates from cattle and deer from the buenos aires province, an important livestock region in argentina, were typed by restriction fragment length polymorphisms (rflp) analysis based on is900. four different rflp patterns (designated 'a', 'b', 'c' and 'e') were identified in bsteii digests of genomic dna. the most frequently observed type, pattern 'a', was found in 46 isolates (75%). the second, pattern 'e', included 8 isolates (13%), while ...199910596808
is1626, a new is900-related mycobacterium avium insertion sequence.an insertion sequence designated is1626 was isolated and characterized from a mycobacterium avium clinical strain. is1626 was detected by high-stringency hybridization with the pmb22/s12 probe from is900 of mycobacterium paratuberculosis. is1626 is 1418 bp in size and has a g+c content of 65 mol%. it has neither terminal inverted repeats nor flanking direct repeats. analysis of three is1626 insertion sites in the m. avium strain and the corresponding potential insertion sites in two is1626-free ...199910589724
pathogenesis of mycobacterium avium subspecies paratuberculosis infections in ruminants: still more questions than answers.mycobacterium avium subspecies paratuberculosis is the etiologic agent of paratuberculosis (johnes disease), a chronic enteritis in ruminants, which is one of the most widespread bacterial diseases of domestic animals, causing enormous economic losses worldwide. though the disease was first described more than a century ago, the biology of the infecting organism and the mechanisms of its interactions with the host still remain a mystery. in this review, recent advances made on pathogenesis of pa ...199910572316
bacterial isolation, immunological response, and histopathological lesions during the early subclinical phase of experimental infection of goat kids with mycobacterium avium subsp. paratuberculosis.the diagnosis of mycobacterium avium subsp. paratuberculosis infection is difficult, especially in the early stages of disease. this is due to the long incubation period, the variable lag phase associated with bacterial proliferation, and the multifocal distribution of slowly developing lesions. there are few previous studies of the early stages of experimental paratuberculosis in goats. in the present study, the ability of conventional diagnostic methods to detect m. a. paratuberculosis infecti ...199910568435
effects of subclinical bovine paratuberculosis on in-vitro polymorphonuclear neutrophil migration.migration of polymorphonuclear neutrophils (pmns) [unstimulated or stimulated with zymosan-activated serum (zas)] from 18 cows was measured in a microwell filter assay. of these animals, 10 were subclinically infected with mycobacterium paratuberculosis and shown by culture to be excreting the organism in the faeces; the remaining eight were clinically normal and negative for m. paratuberculosis on faecal culture. pmn "net migration" (stimulated minus unstimulated cells) of the infected cows was ...199910541483
serological cross-sectional study of paratuberculosis in cattle in austria.from 1995 to 1997, the prevalence of serum antibodies against mycobacterium avium subspecies paratuberculosis (m. av. ssp. ptbc.)--the causal agent of paratuberculosis (johne's disease)--was examined in 11,028 austrian cattle. samples from the four oldest cattle on 2757 farms were collected according to a specific sampling schedule for this epidemiological study. district, age and breed of animals were included as variables in this study. for antibody screening against m. avium subspecies paratu ...199910528542
standardisation of restriction fragment length polymorphism analysis for mycobacterium avium subspecies paratuberculosis.dna from 1008 strains of mycobacterium avium subspecies paratuberculosis, digested by restriction endonucleases psti and bsteii, was hybridised with a standard is900 probe prepared by pcr and labelled non-radioactively by ecl. dna fingerprints were scanned by ccd camera and analysed using the software gel compar (applied maths, kortrijk, belgium). thirteen restriction fragment length polymorphism (rflp) (psti) types were detected, which where designated as a, b, c, d, e, f, g, h, i, j, k, l and ...199910520596
the mycobacterium tuberculosis katg promoter region contains a novel upstream activator.an escherichia coli-mycobacterial shuttle vector, pjcluc, containing a luciferase reporter gene, was constructed and used to analyse the mycobacterium tuberculosis katg promoter. a 1.9 kb region immediately upstream of katg promoted expression of the luciferase gene in e. coli and mycobacterium smegmatis. a smaller promoter fragment (559 bp) promoted expression with equal efficiency, and was used in all further studies. two transcription start sites were mapped by primer extension analysis to 47 ...199910517603
[detection of mycobacterium avium subspecies paratuberculosis (m. p.) by the polymerase chain reaction (pcr) and culture experiments in animals in austria].the polymerase chain reaction and cultural method was applied to detect mycobacterium avium subspecies paratuberculosis (m. p.) in fecal samples of 165 suspected and of 35 diseased cattle, 18 intestinal tissues and 14 lymph nodes of diseased ruminants as well as organ material (n = 10) were also tested. an agreement (+/+, -/-) in the results between both methods was found in 89.7% of all cases examined. 12.7% of samples of suspected and 9.1% of diseased animals were only positive by pcr. in case ...199910472716
lack of support for a common etiology in johne's disease of animals and crohn's disease in humans.the superficial similarity of johne's disease to crohn's disease led to the hypothesis that, like the former. crohn's disease was caused by mycobacterium paratuberculosis. detailed pathologic comparisons, however, reveal little similarity between these two entities, including the lack of important extraintestinal manifestations. attempts to recover m. paratuberculosis by culture have only rarely succeeded and the significance of spheroplasts that appear more frequently on culture is seriously in ...199910453375
a novel polymorphic genetic locus in members of the mycobacterium tuberculosis complex.it has previously been shown that the pan promoter from mycobacterium paratuberculosis can be used as a dna probe to identify an rflp between wild-type mycobacterium bovis and the vaccine strain mycobacterium bovis bcg. to investigate the genetic basis of this phenomenon, dna fragments from a new zealand m. bovis cattle strain and m. bovis bcg pasteur, containing the pan-binding region, were isolated from gene libraries, sequenced and characterized. sequence analysis and comparison with database ...199910439408
factors influencing the isolation of mycobacterium avium subsp. paratuberculosis from bovine fecal samples.a modified procedure was used for culture of mycobacterium paratuberculosis (mptb) from bovine feces. bovine fecal samples were decontaminated with naoh, exposed to a mixture of oxalic acid and malachite green, incubated in a mixture of neomycin and amphotericin b. decontaminated specimens were inoculated onto modified löwenstein-jensen medium. specimens processed by high-speed centrifugation showed growth earlier than specimens prepared by low-speed centrifugation. however, the overall number o ...199910424651
herd-level economic losses associated with johne's disease on us dairy operations.johne's disease ('paratuberculosis') is a chronic, infectious, wasting disease that affects dairy cattle. estimation of its impact on herd productivity and corresponding economic loss on us dairy operations was part of the usda national animal health monitoring system's (nahms) 1996 national dairy study. johne's-positive herds experience an economic loss of almost us$ 100 per cow when compared to johne's-negative herds due to reduced milk production and increased cow-replacement costs. for johne ...199910423773
hepatic encephalopathy associated with paratuberculosis in a goat.a 3-year-old pregnant nubian goat that was examined because of weight loss, weakness, and change in attitude was determined to be infected with mycobacterium paratuberculosis. signs of depressed attitude, trembling, and ataxia were consistent with hepatic encephalopathy, which was confirmed by detection of hyperammonemia. these signs were consistent with histopathologic lesions in the liver and brain. changes in energy balance and the hypoproteinemia that often develop in goats with paratubercul ...199910416479
characterization of mycobacterium paratuberculosis p36 antigen and its seroreactivities in crohn's disease.recent data using improved cultural, molecular, and serological techniques have strengthened the association of mycobacterium paratuberculosis with crohn's disease, an inflammatory bowel disease (ibd) with unknown etiology. to provide more evidence of an etiological association, antibody reactivities of crohn's disease patients were tested by immunoblotting against m. paratuberculosis-recombinant antigens. a clone containing a 1,402-bp insert and expressing a 36k-antigen (p36) was analyzed. no h ...199910398839
the groes antigens of mycobacterium avium and mycobacterium paratuberculosis.the groes antigen provokes a strong immune response in human beings with tuberculosis or leprosy. we cloned and sequenced the mycobacterium avium and mycobacterium paratuberculosis groes genes. m. avium and m. paratuberculosis have identical groes sequences which differ from other mycobacterial species. this supports the current formal designation of m. paratuberculosis as m. avium subsp. paratuberculosis. immunodominant epitopes from mycobacterium tuberculosis groes are conserved in m. avium, b ...199910392775
serum antibodies to mycobacterium paratuberculosis in patients with crohn's disease.mycobacterium paratuberculosis has been suggested as a causative organism of crohn's disease. despite a long-term debate to prove this possibility, the role of this bacteria in the pathogenesis of crohn's disease is still a subject of controversy. in the present study, serum antibodies (igg, iga, and igm) to the protoplasmic antigen of m. paratuberculosis were quantified in patients with crohn's disease and in control subjects by using an enzyme-linked immunosorbent assay whose specificity was i ...199910389697
effect of higher pasteurization temperatures, and longer holding times at 72 degrees c, on the inactivation of mycobacterium paratuberculosis in milk.raw cow's milk spiked with 10(6) cfu ml-1 of mycobacterium paratuberculosis was subjected to heat treatments of 72, 75, 78, 80, 85 or 90 degrees c for 15 s, and 72 degrees c for 20 and 25 s, using laboratory pasteurizing units. three bovine strains of myco. paratuberculosis were studied (nctc 8578, b2 and dvl 943). each strain was subjected to all the heat treatments indicated on three separate occasions. although each of the heat treatments achieved a substantial (5-6 log10) reduction in number ...199910389265
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