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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
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
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
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
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
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
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
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
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
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
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
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
characterization of is900 loci in mycobacterium avium subsp. paratuberculosis and development of multiplex pcr typing 200011101687
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
[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
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
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
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
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
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 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
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
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
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
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
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
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
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
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
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
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
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
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
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
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 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
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
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
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
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
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
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
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
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
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
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
sensitivity and specificity of two serological tests for the detection of ovine paratuberculosis.to determine the sensitivity and specificity of an absorbed elisa and an agid test for the detection of clinical and subclinical paratuberculosis in sheep.200011194475
comparison of three serological tests and an interferon-gamma assay for the diagnosis of paratuberculosis in experimentally infected sheep.to compare the diagnostic performance of a complement fixation test, an agar gel immunodiffusion test, an enzyme-linked immunosorbent assay, and a whole-blood interferon-gamma assay for paratuberculosis in 14 sheep experimentally infected with mycobacterium avium subsp paratuberculosis.200011194726
experimental inoculation of laboratory animals with samples collected from sarcoidal patients and molecular diagnostic evaluation of the results.studies on the implication of mycobacteria in the pathogenesis of sarcoidosis have generated conflicting results. in an attempt to further elucidate the etiology of the disease, we obtained broncho-alveolar lavage (bal) samples from sarcoidal patients, which were subsequently used for intra-tracheal inoculation of a group of rabbits. patients were characterized as sarcoidal on the grounds of clinical, radiographic, histological and microbiological testing. four months following inoculation, lung ...200011204496
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, ...200011338484
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
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
immunohistochemical detection of mycobacterium paratuberculosis in formalin-fixed, paraffin-embedded bovine tissue sections. 200010690778
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
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
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
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
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
isolation of mycobacterium avium subsp paratuberculosis from breast milk of crohn's disease patients. 200010763975
mycobacterium paratuberculosis heat resistance. 200010792659
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
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
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
differential changes in heat shock protein-, lipoarabinomannan-, and purified protein derivative-specific immunoglobulin g1 and g2 isotype responses during bovine mycobacterium avium subsp. paratuberculosis infection.bovine paratuberculosis is caused by infection of young calves with mycobacterium avium subsp. paratuberculosis. in some of the chronically infected cows the long asymptomatic stage (2 to 4 years) is followed by a rapid progression to a clinical stage due to protein-losing enteropathy, which will ultimately be fatal. the current dogma is that in early stages of disease the cell-mediated responses predominate, whereas in the clinical stage of the disease the humoral responses prevail, possibly si ...200111179318
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 ...200111765232
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 ...200111768125
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 ...200111770646
isolation of mycobacterium avium subsp paratuberculosis from the semen of rams with clinical johne's disease. 200111789915
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 ...200111831436
mycobacterium avium subspecies paratuberculosis: a review of current knowledge.although mycobacterium avium subsp. paratuberculosis infection has had its greatest effect on domestic agricultural animal species, it can also have a significant impact on wildlife species. more cases of infection are being reported, and because of its ability to elude immunologic control and to persist in the environment, m. paratuberculosis may spread within and among captive and free-ranging wildlife populations in the absence of organized control programs. studies to improve our ability to ...200112785677
rapid detection of mycobacterium avium subsp. paratuberculosis from cattle and zoo animals by nested pcr.paratuberculosis, caused by mycobacterium avium subsp. paratuberculosis, a suspect causative agent of crohn's disease in man, is an emerging disease of international proportions affecting all ruminants. early stage detection of mycobacterium avium subsp. paratuberculosis infection would accelerate progress in control programmes. despite new molecular approaches the standard diagnostic test for this disease is at present still the time consuming classic isolation procedure. therefore, alternative ...200112789121
mycobacterium avium infection in an ostrich (struthio camelus).acid-fast organisms were identified by histopathology of granulomatous lesions in an ostrich (struthio camelus). the organisms were grown in herrold's egg media with and without mycobactin and identified as mycobacterium avium. an agar gel immunodiffusion (agid) test for mycobacterium avium paratuberculosis was performed for detection of antibody for m. avium in this infected ostrich and seven other ostriches that were in contact. the results of the agid were consistent with the pathologic diagn ...200112790402
mycobacterium avium subsp. paratuberculosis infection in an addax (addax nasomaculatus).mycobacterium avium subsp. paratuberculosis was cultured from a single fecal sample collected from a 10-yr-old, captive-bred male addax (addax nasomaculatus). attempts to confirm infection with additional fecal cultures, serology, semen culture, and tissue biopsy were unsuccessful. there were no gross lesions on necropsy. on histopathology there were neither acid-fast organisms nor microscopic changes suggestive of active or clinical johne's disease. mycobacterium avium subsp. paratuberculosis w ...200112790428
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.200111349414
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 ...200111352488
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 ...200111352594
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 ...200111356251
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 ...200111374694
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 ...200111375202
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 ...200111378513
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 ...200111390109
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 ...200111390110
[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 ...200111392987
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 ...200111393814
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 ...200111427429
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 ...200111432810
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 ...200111437505
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 ...200111449907
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 ...200111457480
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 ...200111488816
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 ...200111504216
[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 ...200111505846
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.200111518178
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 ...200111520620
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 ...200111525992
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 ...200111526024
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 ...200111526132
[current paratuberculosis management by the health department]. 200111544930
comparison of immunomagnetic bead separation-polymerase chain reaction and faecal culture for the detection of mycobacterium avium subsp paratuberculosis in sheep faeces. 200111549050
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 ...200111549181
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