TitleAbstractYear(sorted descending)
streptococcus salivarius fimbriae are composed of a glycoprotein containing a repeated motif assembled into a filamentous nondissociable structure.streptococcus salivarius, a gram-positive bacterium found in the human oral cavity, expresses flexible peritrichous fimbriae. in this paper, we report purification and partial characterization of s. salivarius fimbriae. fimbriae were extracted by shearing the cell surface of hyperfimbriated mutant a37 (a spontaneous mutant of s. salivarius atcc 25975) with glass beads. preliminary experiments showed that s. salivarius fimbriae did not dissociate when they were incubated at 100 degrees c in the p ...200111292790
identification of thermophilic campylobacter spp. by phenotypic and molecular methods.the differences between phenotyping and genotyping (polymerase chain reaction- restriction fragment length polymorphism) of campylobacter jejuni, campylobacter coli, campylobacter lari and campylobacter upsaliensis were assessed.200111298244
bacteriophage-bacteriophage interactions in the evolution of pathogenic bacteria.many bacteriophages carry virulence genes encoding proteins that play a major role in bacterial pathogenesis. recently, investigators have identified bacteriophage-bacteriophage interactions in the bacterial host cell that also contribute significantly to the virulence of bacterial pathogens. the relationships between the bacteriophages pertain to one bacteriophage providing a helper function for another, unrelated bacteriophage in the host cell. accordingly, these interactions can involve the m ...200111303502
survival of campylobacter jejuni during stationary phase: evidence for the absence of a phenotypic stationary-phase response.when campylobacter jejuni nctc 11351 was grown microaerobically in rich medium at 39 degrees c, entry into stationary phase was followed by a rapid decline in viable numbers to leave a residual population of 1% of the maximum number or less. loss of viability was preceded by sublethal injury, which was seen as a loss of the ability to grow on media containing 0.1% sodium deoxycholate or 1% sodium chloride. resistance of cells to mild heat stress (50 degrees c) or aeration was greatest in exponen ...200111319108
study of the infectivity of saline-stored campylobacter jejuni for day-old chicks.the culturability of three campylobacter jejuni strains and their infectivity for day-old chicks were assessed following storage of the strains in saline. the potential for colonization of chicks was weakened during the storage period and terminated 3 to 4 weeks before the strains became nonculturable. the results from this study suggest that the role of starved and aged but still culturable campylobacters may be diminutive, but even more, that the role of viable but nonculturable stages in camp ...200111319130
recommendations of the subcommittee on the taxonomy of campylobacter and related bacteria.the icsb subcommittee on the taxonomy of campylobacter and related bacteria has discussed several contemporaneous issues and makes the following recommendations. (i) the reported synonymy between campylobacter coli and campylobacter hyoilei was based on valid taxonomic arguments. the subcommittee therefore discourages the use of the name c. hyoilei. (ii) the revised infrasubspecific nomenclature of campylobacter sputorum is endorsed. c sputorum is subdivided into c. sputorum biovar sputorum (cha ...200111321120
rapid pulsed-field gel electrophoresis protocol for subtyping of campylobacter jejuni.we developed a rapid pulsed-field gel electrophoresis (pfge) protocol for subtyping campylobacter isolates based on the standardized protocols used by pulsenet laboratories for the subtyping of other food-borne bacterial pathogens. various combinations of buffers, reagents, reaction conditions (e.g., cell suspension concentration, lysis time, lysis temperature, and restriction enzyme concentration), and electrophoretic parameters were evaluated in an effort to devise a protocol that is simple, r ...200111326009
comparison of two methods for serotyping campylobacter spp.two serotyping schemes (penner and laboratory of enteric pathogens [lep]) based on soluble heat-stable antigens were used to analyze 3,788 campylobacter sp. isolates. a significant percentage (36.6%) was untypeable using lep serotyping; greater cross-reaction was also observed. the relative discrimination capabilities of the techniques were similar. penner serotyping fulfils more of the requisite criteria for typing methods.200111326013
superoxide dismutase-deficient mutants of helicobacter pylori are hypersensitive to oxidative stress and defective in host colonization.superoxide dismutase (sod) is a nearly ubiquitous enzyme among organisms that are exposed to oxic environments. the single sod of helicobacter pylori, encoded by the sodb gene, has been suspected to be a virulence factor for this pathogenic microaerophile, but mutations in this gene have not been reported previously. we have isolated mutants with interruptions in the sodb gene and have characterized them with respect to their response to oxidative stress and ability to colonize the mouse stomach ...200111349073
changes in the carriage of campylobacter strains by poultry carcasses during processing in abattoirs.the recent development of simple, rapid genotyping techniques for campylobacter species has enabled investigation of the determinative epidemiology of these organisms in a variety of situations. in this study we have used the technique of fla typing (pcr-restriction fragment length polymorphism analysis of the flaa and flab genes) to identify the sources of strains contaminating the carcasses of five campylobacter-positive and two campylobacter-negative broiler flocks during abattoir processing. ...200111375174
evidence that certain clones of campylobacter jejuni persist during successive broiler flock rotations.through the national surveillance program for campylobacter spp., nine broiler chicken farms that were infected with campylobacter jejuni in at least five rotations in 1998 were identified. one additional farm, located at the island of bornholm where divided slaughter is used extensively, was also selected. twelve broiler houses located on 10 farms were included in the study. the c. jejuni isolates collected from the selected houses during the surveillance were typed using fla typing and macrore ...200111375189
etiology of children's diarrhea in montevideo, uruguay: associated pathogens and unusual isolates.we studied microorganisms associated with infant diarrhea in a group of 256 children admitted to a public pediatric hospital in montevideo, uruguay. diagnostic procedures were updated to optimize detection of potential pathogens, which were found in 63.8% of cases, and to be able to define their characteristics down to molecular or antigenic type. coinfection with two or more agents was detected in more than one-third of positive studies. escherichia coli enteric virotypes, especially enteropath ...200111376047
coinfection of enteric helicobacter spp. and campylobacter spp. in cats.during a 6-year period, 64 of 227 commercially reared cats had microaerobic bacteria isolated from their feces. all the isolates were initially identified as campylobacter-like organisms based on biochemical and phenotypic characteristics. dna extractions from 51 of these isolates were subjected to pcr using primers specific for helicobacter spp. and campylobacter spp. of the isolates, 92% (47 of 51 isolates) were positive for campylobacter spp., 41% (21 of 51 isolates) were positive for helicob ...200111376052
rapid identification of campylobacter spp. by melting peak analysis of biprobes in real-time pcr.we describe rapid pcr-biprobe identification of campylobacter spp. this is based on real-time pcr with product analysis in the same system. the assay identifies enteropathogenic campylobacters to the species level on the basis of their degree of hybridization to three 16s ribosomal dna (rdna) biprobes. first-round symmetric pcr is performed with genus-specific primers which selectively target and amplify a portion of the 16s rrna gene common to all campylobacter species. second-round asymmetric ...200111376061
comparative study using amplified fragment length polymorphism fingerprinting, pcr genotyping, and phenotyping to differentiate campylobacter fetus strains isolated from animals.a collection of campylobacter fetus strains, including both c. fetus subsp. fetus and c. fetus subsp. venerealis, were phenotypically identified to the subspecies level and genotypically typed by pcr and amplified fragment length polymorphism (aflp) analysis. phenotypic subspecies determination methods were unreliable. genotyping of the strains by pcr and aflp showed a clear discrimination between the two subspecies.200111376071
changes in campylobacter jejuni and campylobacter coli carriage rates in the zenica region [correction of zenica canton] of bosnia and herzegovina in the pre- and postwar periods. 200111388169
differential gene expression from two transcriptional units in the cag pathogenicity island of helicobacter pylori.infection with helicobacter pylori strains containing the cag pathogenicity island (cag pai) is strongly correlated with the development of severe gastric disease, including gastric and duodenal ulceration, mucosa-associated lymphoid tissue lymphoma, and gastric carcinoma. although in vitro studies have demonstrated that the expression of genes within the cag pai leads to the activation of a strong host inflammatory response, the functions of most cag gene products and how they work in concert t ...200111401955
cdta, cdtb, and cdtc form a tripartite complex that is required for cytolethal distending toxin activity.campylobacter jejuni encodes a cytolethal distending toxin (cdt) that causes cells to arrest in the g(2)/m transition phase of the cell cycle. highly related toxins are also produced by other important bacterial pathogens. cdt activity requires the function of three genes: cdta, cdtb, and cdtc. recent studies have established that cdtb is the active subunit of cdt, exerting its effect as a nuclease that damages the dna and triggers cell cycle arrest. microinjection of cdtb into target cells led ...200111401974
differentiation between campylobacter hyoilei and campylobater coli using genotypic and phenotypic analyses.genotypic and phenotypic methods were applied to investigate differences between the closely related species campylobacter hyoilei and campylobacter coli. a unique dna sequence from c. hyoilei was used to design a specific pcr assay that amplified a dna product of 383 bp for all c. hyoilei strains, but not other campylobacter species, including c. coli. the pcr assay could detect 100 fg pure c. hyoilei dna, 2 x 10(2) c.f.u. ml(-1) using cultured cells and 8.3 x 10(3) c.f.u. 0.1 g(-1) in faeces. ...200111411703
serotype and genotype diversity and hatchery transmission of campylobacter jejuni in commercial poultry flocks.we investigated the genotype and serotype diversity of campylobacter coli and c. jejuni in two parent flocks of adult hens and their offspring over two rotations in order to evaluate the role of hatchery mediated transmission and/or vertical transmission of campylobacters in broiler flocks. in total, 314 c. jejuni and 32 c. coli isolates from parent and broiler flocks and from the surroundings of broiler houses were typed by flagellin gene pcr/rflp (fla-typing), and selected isolates were also t ...200111423205
comparison of genotypes and serotypes of campylobacter jejuni isolated from danish wild mammals and birds and from broiler flocks and humans.the incidence of human infection with campylobacter jejuni is increasing in most developed countries and the reason for this is largely unknown. although poultry meat is considered to be a major source, it is evident that other reservoirs exist, possibly common to humans and poultry. environmental sources are believed to be important reservoirs of campylobacter infection in broiler chicken flocks. we investigated the potential importance of wildlife as a source of infection in commercial poultry ...200111425730
evaluation of methods for subtyping campylobacter jejuni during an outbreak involving a food october 1998, the centers for disease control and prevention (cdc) assisted in an investigation of an outbreak of campylobacteriosis at a school in salina, kansas. twenty-two isolates were submitted from the kansas state public health laboratory to cdc, 9 associated with the outbreak and 13 epidemiologically unrelated sporadic isolates. pulsed-field gel electrophoresis (pfge) using smai and sali was initially used to validate the epidemiologic data. we then tested the ability of other subtypi ...200111427543
helicobacter winghamensis sp. nov., a novel helicobacter sp. isolated from patients with gastroenteritis.from 1997 to 1999 seven isolates of campylobacter-like organisms from five patients that were exhibiting symptoms of gastroenteritis, including fever, stomach malaise, and diarrhea, were investigated. the organisms were isolated from stool samples and found to exhibit a diverse colony morphology; hence multiple isolates were submitted from one of the patients. all isolates were found to be identical. the organisms were catalase, urease, alkaline phosphatase, and nitrate negative but oxidase and ...200111427547
genomic heterogeneity and o-antigenic diversity of campylobacter upsaliensis and campylobacter helveticus strains isolated from dogs and cats in germany.a serotyping scheme based on heat-stable surface antigens was established for 101 campylobacter upsaliensis and 10 campylobacter helveticus strains isolated from 261 dogs and 46 cats of different ages originating from two geographically distinct regions in germany. the prevalence of c. upsaliensis varied between 27.8% in juvenile dogs (<12 months of age) and 55.4% in adult dogs (p < 0.05). of the cats, 19.6% harbored c. upsaliensis, whereas 21.7% carried c. helveticus. of the c. upsaliensis isol ...200111427567
development of a ceue-based multiplex polymerase chain reaction (pcr) assay for direct detection and differentiation of campylobacter jejuni and campylobacter coli in thailand.a novel ceue-based multiplex pcr system was developed as an efficient diagnostics test to detect and differentiate c. jejuni and c. coli. there is no cross reactivity between c. jejuni and c. coli. in addition, the assay does not produce a positive signal from other enteric bacteria including salmonella, shigella and escherichia coli strains. campylobacter detection sensitivity was determined to be equivalent to previously reported pcr for other enteric bacteria. we also noticed that silicon dio ...200111448558
identification of the carbohydrate moieties and glycosylation motifs in campylobacter jejuni flagellin.flagellins from three strains of campylobacter jejuni and one strain of campylobacter coli were shown to be extensively modified by glycosyl residues, imparting an approximate 6000-da shift from the molecular mass of the protein predicted from the dna sequence. tryptic peptides from c. jejuni 81-176 flagellin were subjected to capillary liquid chromatography-electrospray mass spectrometry with a high/low orifice stepping to identify peptide segments of aberrant masses together with their corresp ...200111461915
iron-dependent transcription of the frpb gene of helicobacter pylori is controlled by the fur repressor protein.we have overexpressed and purified the helicobacter pylori fur protein and analyzed its interaction with the intergenic regions of divergent genes involved in iron uptake (frpb and ceue) and oxygen radical detoxification (kata and tsaa). dnase i footprint analysis showed that fur binds specifically to a high-affinity site overlapping the p(frpb) promoter and to low-affinity sites located upstream from promoters within both the frpb-kata and ceue-tsaa intergenic regions. construction of an isogen ...200111466300
antimicrobial susceptibilities of campylobacter strains isolated from food animals in belgium.campylobacter spp. are a frequent cause of diarrhoea in man, originating mostly from poultry. it has been suggested that the veterinary use of antibiotics is largely responsible for resistance in human isolates, particularly to quinolones. during a 6 month period from june to december 1998, 677 campylobacter isolates were obtained from healthy poultry and pigs. samples were taken at belgian slaughterhouses. species identification was performed by biochemical tests, multiplex pcr and sds-page of ...200111481294
a genomic island in pseudomonas aeruginosa carries the determinants of flagellin glycosylation.protein glycosylation has been long recognized as an important posttranslational modification process in eukaryotic cells. glycoproteins, predominantly secreted or surface localized, have also been identified in bacteria. we have identified a cluster of 14 genes, encoding the determinants of the flagellin glycosylation machinery in pseudomonas aeruginosa pak, which we called the flagellin glycosylation island. flagellin glycosylation can be detected only in bacteria expressing the a-type flagell ...200111481492
thermophilic campylobacters in surface water: a potential risk of campylobacteriosis.campylobacteriosis caused by campylobacter jejuni, campylobacter coli and campylobacter lari is one of the most frequently occurring acute gastroenteritis diseases in humans. an important risk factor is untreated drinking water. thermotolerant campylobacters were isolated from bø river water using 100-ml filtrate samples. campylobacters were isolated from 32 of 60 samples (53.3%). of the 75 strains isolated, 47 (62.7%) were detected using the enrichment procedure and 28 (37.2%) by direct plating ...200111798419
[antagonistic activity of lactobacillus bacteria strains against anaerobic gastrointestinal tract pathogens (helicobacter pylori, campylobacter coli, campylobacter jejuni, clostridium difficile)].antagonistic activity of lactobacillus strains has been known for some time. this property is connected with production of many active substances by lactobacilli e.g., organic acids and bacteriocin-like substances which interfere with other indigenous microorganisms inhabiting the same ecological niche, including also anaerobic gastrointestinal tract pathogens. growing interest of clinical medicine in finding new approaches to treatment and prevention of common inflammatory infections of the dig ...200111757422
single or double mutational alterations of gyra associated with fluoroquinolone resistance in campylobacter jejuni and campylobacter coli.we looked for the presence of gyra mutations in seven fluoroquinolone-resistant french clinical isolates of campylobacter jejuni and campylobacter coli. three of the five isolates of c. jejuni and the two isolates of c. coli had high-level resistance to nalidixic acid (mics 128-256 microg/ml) and ciprofloxacin (mics 32 microg/ml). a gyra mutation was found in all these isolates leading to the following substitutions: thr86-ile in four cases and asp90-tyr for one c. coli strain. one isolate had h ...200111759087
isolation and polymerase chain reaction-based detection of campylobacter jejuni and campylobacter coli from poultry in the philippines.the polymerase chain reaction (pcr) and the conventional culture method of detecting thermophilic campylobacter species in duck and chicken samples from two locations in the province of laguna, philippines, were compared. three campylobacter jejuni and five c. coli strains were isolated from a total of 135 duck and chicken samples from both methods. the pcr technique, however, was found to be more sensitive, accurate and rapid than the conventional culture method. the specificity of two sets of ...200111759758
role of flm locus in mesophilic aeromonas species adherence.the adherence mechanism of aeromonas caviae sch3n to hep-2 cells was initially investigated through four mini-tn5 mutants that showed a 10-fold decrease in adherence. these mutants lost motility, flagella, and their lipopolysaccharide (lps) o antigen (o-ag). three genes, flmb-neua-flmd, were found to be interrupted by the transposon insertions; additionally, two other genes, one lying upstream (flma) and one downstream (neub), were found to be clustered in the same operon. while the flma and flm ...200111119490
investigations of waterborne pathogens in eurasian beaver (castor fiber) from telemark county, southeast norway. 200111957376
prevalence of salmonella, campylobacter and vtec on pig farms.four different pig farms were sampled for the prevalence of salmonella, campylobacter and verotoxigenic e. coli (vtec). pigs of different age groups and pigs of the same age were tested by taking rectal swabs. the farm environment was tested by examining overshoes, and the feed and drinking water in the pens. from a total of 215 rectal samples of individual pigs, 15 rectal samples taken from animals at the same farm were positive for salmonella. the salmonella status of the pigs at this farm dif ...200115954621
campylobacter contamination of raw meat and poultry at retail sale: identification of multiple types and comparison with isolates from human infection.campylobacter species are the major cause of acute bacterial enteritis reported in the united kingdom, nonetheless many aspects of campylobacteriosis epidemiology remain poorly understood. the aim of this study was to determine the prevalence of campylobacter jejuni and campylobacter coli in fresh bovine, ovine, and porcine liver and chicken portions from retail outlets and compare strain subtype distributions with those associated with cases of human campylobacteriosis occurring within the same ...200011131886
agglutination of helicobacter pylori coccoids by lectins.aim:to study the agglutination pattern of helicobacter pylori coccoid andspiral forms.methods:assays of agglutination and agglu-tination inhibition were applied using fifteen commercial lectins.results:strong agglutination was observed with mannose specific concanavalin a(con a), fucose specific tetragonolobus purpureas(lotus a) and n-acetyl glucosamine-specific triticum vulgaris (wga) lectins. mannose and fucose specific lectins were reactive with all strains of h. pylori coccoids as compared t ...200011819557
thermophilic campylobacter spp. in danish broiler production: a cross-sectional survey and a retrospective analysis of risk factors for occurrence in broiler order to elucidate the rate of thermophilic campylobacter spp. carriage in danish broiler production and to identify risk factors for occurrence of campylobacter in broiler flocks, a total of 88 randomly selected broiler flocks were tested for campylobacter infection, and a subsequent study of risk factors based on a questionnaire was conducted. the sample material comprised cloacal swabs from live birds before slaughter, and neck skin samples from carcasses at the end of the processing line. ...200019184798
a campylobacter coli foodborne outbreak in may 1995, the scientific institute of public health was informed of an outbreak of gastrointestinal illness in a congregational school in the brussels area. the field investigation identified 24 cases with mild to severe gastrointestinal and general symptoms of acute bacterial enterocolitis. campylobacter coli was detected in the stools of 5 patients. a retrospective cohort study suggested that a mixed salad (containing ham and feta cheese) was the probable source of infection, but the route ...200011484421
report a case of campylobacter coli bacteremia in a patient with gastro-enteritis. 200011484426
improved repetitive-element pcr fingerprinting of salmonella enterica with the use of extremely elevated annealing temperatures.modified thermal cycling conditions were explored in an effort to improve the reproducibility and resolving power of repetitive-element pcr (rep-pcr) fingerprinting. assay performance was rigorously evaluated under standard and modified cycling conditions, using as a test set 12 strains putatively representing 12 serovars of salmonella enterica. for all three fingerprint types (eric2, boxa1r, and composite fingerprints), the use of extremely elevated annealing temperatures plus an initial "touch ...200010702502
serum amyloid p component bound to gram-negative bacteria prevents lipopolysaccharide-mediated classical pathway complement activation.although serum amyloid p component (sap) is known to bind many ligands, its biological function is not yet clear. recently, it was demonstrated that sap binds to lipopolysaccharide (lps). in the present study, sap was shown to bind to gram-negative bacteria expressing short types of lps or lipo-oligosaccharide (los), such as salmonella enterica serovar copenhagen re and escherichia coli j5, and also to clinical isolates of haemophilus influenzae. it was hypothesized that sap binds to the bacteri ...200010722560
chronic atrophic gastritis in scid mice experimentally infected with campylobacter fetus.campylobacter fetus is a cause of enteritis and invasive extraintestinal disease in humans. in order to develop an animal model of c. fetus infection, outbred icr scid mice were orally challenged with a clinical isolate of c. fetus. the stomachs of scid mice were heavily colonized with c. fetus, and colonization was associated with the development of chronic atrophic gastritis. this lesion was characterized by an inflammatory infiltrate of granulocytes and macrophages that over time resulted in ...200010722608
detection and differentiation of campylobacter jejuni and campylobacter coli in broiler chicken samples using a pcr/dna probe membrane based colorimetric detection assay.campylobacter enteritis in humans has been linked to consumption of poultry meat. surveys show that 30-100% of poultry harbour campylobacter as normal flora of the digestive tract which indicates a need to identify prevalent organism types in flocks and trace their epidemiology. in this study we describe a campylobacter genus specific polymerase chain reaction (pcr) assay, amplifying the 16 s-23 s rrna intergenic spacer region with an internal campylobacter genus specific dna probe and species s ...200010725058
lipopolysaccharides of a campylobacter coli isolate from a patient with guillain-barré syndrome display ganglioside mimicry.campylobacter coli was isolated from a patient with severe, axonal type guillain-barré syndrome (gbs). the patient's serum was tested by elisa for glycolipid antibodies and showed a high titer of igg antibodies to asialo-gm1 (ga1) and gd3. campylobacter coli lipopolysaccharide (lps) was extracted and analyzed by elisa, immunoblot binding and blocking studies, and found to avidly bind cholera toxin and peanut agglutinin. the lps from the patient's isolate also induced anti-ga1 antibodies in a rat ...200010734265
molecular characterization of two-component systems of helicobacter pylori.two-component systems are frequently involved in the adaptation of bacteria to changing environmental conditions at the level of transcriptional regulation. here we report the characterization of members of the two-component systems of the gastric pathogen helicobacter pylori deduced from the genome sequence of strain 26695. we demonstrate that the response regulators hp166, hp1043, and hp1021 have essential functions, as disruption of the corresponding genes is lethal for the bacteria, irrespec ...200010735847
identification of campylobacter jejuni, c. coli, c. lari, c. upsaliensis, arcobacter butzleri, and a. butzleri-like species based on the glya gene.currently, the detection and identification of campylobacter and arcobacter species remains arduous, largely due to cross-species phenotypic similarities and a relatively narrow spectrum of biochemical reactivity. we have developed a pcr-hybridization strategy, wherein degenerate primers are used to amplify glya fragments from samples, which are then subjected to species-specific oligodeoxyribonucleotide probe hybridizations, to identify and distinguish between campylobacter jejuni, c. coli, c. ...200010747131
restriction fragment length polymorphism analysis using random chromosomal gene probes for epidemiological analysis of campylobacter jejuni infections.we have evaluated the ability of a new genotyping method for campylobacter jejuni based on restriction fragment length polymorphisms using random chromosomal gene probes. dnas from c. jejuni strains digested with each of three restriction enzymes, hhai, haeiii, and hpaii, were analyzed by southern hybridization using each of two unrelated cosmid clones, p14 and p15 (respectively containing 30- and 35-kb genomic dna fragments of c. jejuni strain oh4384). the method reported provides a stable and ...200010747164
a field-suitable, semisolid aerobic enrichment medium for isolation of campylobacter jejuni in small numbers.the objective of this study was to produce an economical, easy to prepare, field-suitable enrichment medium for detection of campylobacter jejuni in small numbers. a semisolid aerobic enrichment medium was developed. rates of recovery from inoculated medium, sterile swabs, and mixed cultures of c. jejuni and coliform bacteria were tested.200010747165
the gale gene of campylobacter jejuni is involved in lipopolysaccharide synthesis and virulence.lipopolysaccharide (lps) is one of the main virulence factors of gram-negative bacteria. the lps from campylobacter spp. has endotoxic properties and has been shown to play a role in adhesion. we previously cloned a gene cluster (wla) which is involved in the synthesis of the campylobacter jejuni 81116 lps molecule. sequence alignment of the first gene in this cluster indicated similarity with gale genes. these genes encode a udp-glucose 4-epimerase, which catalyzes the interconversion of udp-ga ...200010768949
antibiotic resistance trends in enteropathogenic bacteria isolated in 1985-1987 and 1995-1998 in barcelona.trends in resistance to antimicrobial agents used for therapy have been evaluated with 3,797 enteropathogenic bacteria, campylobacter, salmonella, shigella, and yersinia, between 1985-1987 and 1995-1998. the greater increase in the rate of resistance was observed in campylobacter jejuni for quinolones (from 1 to 82%) and tetracycline (from 23 to 72%) and in gastroenteric salmonellae for ampicillin (from 8 to 44%), chloramphenicol (from 1.7 to 26%), and trimethoprim-sulfamethoxazole and nalidixic ...200010770742
rapid and specific enzyme immunoassay on hydrophobic grid membrane filter for detection and enumeration of thermophilic campylobacter spp. from milk and chicken rinses.six commercially available anti-campylobacter antibodies were examined for their applicability in an enzyme immunoassay on hydrophobic grid membrane filters, both for the detection and enumeration of campylobacter spp. when a panel of nine campylobacter (seven campylobacter jejuni and two campylobacter coli) and eight non-campylobacter strains were used in a dot-blot format enzyme immunoassay to test the specificity of these antibodies, only one polyclonal antibody (biodesign) detected all campy ...200010772214
immobilization with metal hydroxides as a means to concentrate food-borne bacteria for detection by cultural and molecular methods.the application of nucleic acid amplification methods to the detection of food-borne pathogens could be facilitated by concentrating the organisms from the food matrix before detection. this study evaluated the utility of metal hydroxide immobilization for the concentration of bacterial cells from dairy foods prior to detection by cultural and molecular methods. using reconstituted nonfat dry milk (nfdm) as a model, two food-borne pathogens (listeria monocytogenes and salmonella enterica serovar ...200010788338
fecal shedding of campylobacter and arcobacter spp. in dairy cattle.campylobacter jejuni, campylobacter coli, and arcobacter spp. were detected in feces of healthy dairy cows by highly specific multiplex-pcr assays. for c. jejuni, at this one-time sampling, cows from 80.6% of farm operations (n = 31) and 37.7% of individual dairy cattle fecal samples (n = 2,085) were positive. farm management factors were correlated with prevalence in herds in which >25% of cows were positive for c. jejuni. statistical significance was set at a p of 0.20. using these criteria, a ...200010788372
helicobacter mesocricetorum sp. nov., a novel helicobacter isolated from the feces of syrian hamsters.a spiral-shaped bacterium with bipolar, single, nonsheathed flagella was isolated from the feces of syrian hamsters. the bacterium grew as a thin spreading film at 37 degrees c under microaerobic conditions, did not hydrolyze urea, was positive for catalase and alkaline phosphatase, reduced nitrate to nitrite, did not hydrolyze hippurate, and was sensitive to nalidixic acid but resistant to cephalothin. sequence analysis of the 16s rrna gene and biochemical and phenotypic criteria indicate that ...200010790105
computer-assisted analysis and epidemiological value of genotyping methods for campylobacter jejuni and campylobacter coli.for epidemiological tracing of the thermotolerant campylobacter species c. jejuni and c. coli, reliable and highly discriminatory typing techniques are necessary. in this study the genotyping techniques of flagellin typing (flaa typing), pulsed-field gel electrophoresis (pfge), automated ribotyping, and amplified fragment length polymorphism (aflp) fingerprinting were compared. the following aspects were compared: computer-assisted analysis, discriminatory power, and use for epidemiological typi ...200010790125
intercellular communication in helicobacter pylori: luxs is essential for the production of an extracellular signaling molecule.individual bacteria of numerous species can communicate and coordinate their actions via the production, release, and detection of extracellular signaling molecules. in this study, we used the vibrio harveyi luminescence bioassay to determine whether helicobacter pylori produces such a factor. cell-free conditioned media from h. pylori strains 60190 and 26695 each induced >100-fold-greater luminescence in v. harveyi than did sterile culture medium. the h. pylori signaling molecule had a molecula ...200010816463
molecular characterization of campylobacter jejuni from patients with guillain-barré and miller fisher syndromes.campylobacter jejuni has been identified as the predominant cause of antecedent infection in guillain-barré syndrome (gbs) and miller fisher syndrome (mfs). the risk of developing gbs or mfs may be higher after infection with specific c. jejuni types. to investigate the putative clonality, 18 gbs- or mfs-related c. jejuni strains from the netherlands and belgium and 17 control strains were analyzed by serotyping (penner and lior), restriction fragment length polymorphism analysis of pcr products ...200010834992
[campylobacter coli-related meningitis in an adult male]. 200010846879
roles of fe superoxide dismutase and catalase in resistance of campylobacter coli to freeze-thaw stress.we demonstrated that oxidative stress plays a role in freeze-thaw-induced killing of campylobacter coli following analysis of mutants deficient in key antioxidant functions. superoxide anions, but not h(2)o(2), were formed during the freeze-thaw process. however, a failure to detoxify superoxide anions may lead to spontaneous disproportionation of the radicals to h(2)o(2).200010877815
helicobacter canadensis sp. nov. isolated from humans with diarrhea as an example of an emerging pathogen.we recently analyzed 11 helicobacter isolates cultured from diarrhea patients in canada. these isolates had been characterized biochemically by restriction fragment length polymorphism (rflp; alui, hhai) analysis and by fatty-acid analysis as helicobacter pullorum. however, four of the isolates differed biochemically from h. pullorum by their inability to hydrolyze indoxyl acetate and their resistance to nalidixic acid. using complete 16s rrna analysis, we determined that these four strains clus ...200010878041
slaughter pigs are commonly infected by closely related but distinct gastric ulcerative lesion-inducing association between (unculturable) gastrospirillum-like organisms (glo) and ulcerative lesions in the pars oesophagea in stomachs of swine has been claimed. in dogs glo detected by microscopy may represent several helicobacter species or subspecies. therefore we investigated which helicobacter spp. are present in stomachs of swine and their possible association with ulcerative lesions of the pars oesophagea. the presence of helicobacter spp. in the antrum and pars oesophagea in 122 stomachs o ...200010878060
antibody to heat shock protein can be used for early serological monitoring of helicobacter pylori eradication treatment.infection with helicobacter pylori induces humoral immune responses against various antigens of the bacterium. heat shock proteins (hsps) are immunodominant antigens in various diseases including h. pylori infection. in the present study, we measured the anti-hsp antibody titers in 42 patients with h. pylori-infected peptic ulcers during a bacterial eradication study. the patients were treated with a proton pump inhibitor and antimicrobial agents to eradicate the organism. their sera were obtain ...200010882654
involvement of a plasmid in virulence of campylobacter jejuni 81-176.campylobacter jejuni strain 81-176 contains two, previously undescribed plasmids, each of which is approximately 35 kb in size. although one of the plasmids, termed ptet, carries a teto gene, conjugative transfer of tetracycline resistance to another strain of c. jejuni could not be demonstrated. partial sequence analysis of the second plasmid, pvir, revealed the presence of four open reading frames which encode proteins with significant sequence similarity to helicobacter pylori proteins, inclu ...200010899834
switching of flagellar motility in helicobacter pylori by reversible length variation of a short homopolymeric sequence repeat in flip, a gene encoding a basal body protein.the genome of helicobacter pylori contains numerous simple nucleotide repeats that have been proposed to have regulatory functions and to compensate for the conspicuous dearth of master regulatory pathways in this highly host-adapted bacterium. h. pylori strain 26695, whose genomic sequence was determined by the institute for genomic research (tigr), contains a repeat of nine cytidines in the flip flagellar basal body gene that splits the open reading frame in two parts. in this work, we demonst ...200010899861
rapid detection of campylobacter jejuni in stool specimens by an enzyme immunoassay and surveillance for campylobacter upsaliensis in the greater salt lake city area.the alexon-trend, inc. (ramsey, minn.), prospect campylobacter microplate assay was compared with culture on a campy-cva plate (remel, lenexa, kans.) and blood-free campylobacter agar with cefoperazone (20 microg/ml), amphotericin b (10 microg/ml), and teicoplanin (4 microg/ml) (cat medium; oxoid limited, hampshire, england) with 631 patient stool samples. the cat medium was used to isolate campylobacter upsaliensis. the enzyme immunoassay (eia) had a sensitivity and a specificity of 89 and 99%, ...200010921981
development of a fluorogenic 5' nuclease pcr assay for detection of the ail gene of pathogenic yersinia this report we describe the development and evaluation of a fluorogenic pcr assay for the detection of pathogenic yersinia enterocolitica. the assay targets the chromosomally encoded attachment and invasion gene, ail. three primer-probe sets (tm1, tm2, and tm3) amplifying different, yet overlapping, regions of ail were examined for their specificity and sensitivity. all three primer-probe sets were able to detect between 0.25 and 0.5 pg of purified y. enterocolitica dna. tm1 identified all 26 ...200010966386
amplified fragment length polymorphism analysis of campylobacter jejuni strains isolated from chickens and from patients with gastroenteritis or guillain-barré or miller fisher syndrome.the high-resolution genotyping method of amplified fragment length polymorphism (aflp) analysis was used to study the genetic relationships between campylobacter jejuni strains infecting chickens (n = 54) and those causing gastroenteritis in humans (n = 53). in addition, c. jejuni strains associated with the development of guillain-barré syndrome (gbs) (n = 14) and miller fisher syndrome (mfs) (n = 4), two related acute paralytic syndromes in human, were included. strains were isolated between 1 ...200010966409
application of the 5'-nuclease pcr assay in evaluation and development of methods for quantitative detection of campylobacter jejuni.campylobacter jejuni is recognized as a leading human food-borne pathogen. traditional diagnostic testing for c. jejuni is not reliable due to special growth requirements and the possibility that this bacterium can enter a viable but nonculturable state. nucleic acid-based tests have emerged as a useful alternative to traditional enrichment testing. in this article, we present a 5'-nuclease pcr assay for quantitative detection of c. jejuni and describe its evaluation. a probe including positions ...200010966425
quantitative immunocapture pcr assay for detection of campylobacter jejuni in foods.the rapid detection of food-borne bacterial pathogens as part of a quality control program is necessary for the maintenance of a safe food supply. in this report, we present our findings for an immunocapture pcr method for the detection of campylobacter jejuni in foods. the method permits direct detection of the pathogen without an enrichment step and can be performed in approximately 8 h. assay results are quantitative, and one cell in a milliliter sample can be detected. application of the met ...200010966437
phenotypic and genotypic diversity of the flagellin gene (flic) among clostridium difficile isolates from different serogroups.phenotypic and genotypic diversity of the flagellin gene (flic) of clostridium difficile was studied in 47 isolates from various origins belonging to the serogroups a, b, c, d, f, g, h, i, k, x, and s3. electron microscopy revealed 17 nonflagellated strains and 30 flagellated strains. pcr and reverse transcription-pcr demonstrated that the flagellin gene was present in all strains and that the flic gene was expressed in both flagellated and nonflagellated strains. southern blotting showed the pr ...200010970353
comparative fingerprinting analysis of campylobacter jejuni subsp. jejuni strains by amplified-fragment length polymorphism genotyping.amplified-fragment length polymorphism (aflp) analysis with the endonucleases bglii and mfei was used to genotype 91 campylobacter jejuni subsp. jejuni strains from outbreaks and sporadic cases. aflp-generated fragments were labeled with fluorescent dye and separated by capillary electrophoresis. the software packages genescan and gelcompar ii were used to calculate aflp pattern similarities and to investigate phylogenetic relationships among the genotyped strains. the aflp method was compared w ...200010970387
automated 5' nuclease pcr assay for identification of salmonella enterica.a simple and ready-to-go test based on a 5' nuclease (taqman) pcr technique was developed for identification of presumptive salmonella enterica isolates. the results were compared with those of conventional methods. the taqman assay was evaluated for its ability to accurately detect 210 s. enterica isolates, including 100 problematic "rough" isolates. an internal positive control was designed to use the same salmonella primers for amplification of a spiked nonrelevant template (116 bp) in the sa ...200010970396
differentiation of clinical helicobacter pullorum isolates from related helicobacter and campylobacter species.helicobacter pullorum, first detected in the liver and intestinal contents of poultry, was defined as a new species in 1994. this organism has since been isolated from humans with gastroenteritis. phenotypic as well as genotypic methods have been used to identify h. pullorum associated with cases of human disease.200010971678
efficient isolation of campylobacteria from stools. 200010979752
characterization of gyra mutations associated with fluoroquinolone resistance in campylobacter coli by dna sequence analysis and mama pcr.increasing numbers of fluoroquinolone-resistant campylobacter coli isolates received at the minnesota state public health laboratory and at the centers for disease control and prevention have been a cause for concern. the gyra quinolone resistance-determining regions of several fluoroquinolone-resistant isolates were sequenced to examine the mechanism of resistance. ciprofloxacin-resistant c. coli isolates examined by dna sequencing had a thr-86 to ile (act-->att) gyra mutation, leading to resis ...200010981681
susceptibility to secondary bacterial infections in growing pigs as an early response in ochratoxicosis.mycotoxic nephropathy was induced in twelve 14 kg pigs fed a dietary component, moulded by aspergillus ochraceus and contributing ochratoxin a at 1 or 3 ppm for up to 3 weeks. concurrently, salmonellosis arose spontaneously in all six animals treated at 3 ppm and all died between days 15 and 17. two of the six pigs in the 1 ppm group died similarly but the rest, and all of six control animals, were unaffected. clinical biochemistry and histology revealed changes typical of renal ochratoxicosis i ...200010987179
sequence polymorphism, predicted secondary structures, and surface-exposed conformational epitopes of campylobacter major outer membrane protein.the major outer membrane protein (momp), a putative porin and a multifunction surface protein of campylobacter jejuni, may play an important role in the adaptation of the organism to various host environments. to begin to dissect the biological functions and antigenic features of this protein, the gene (designated cmp) encoding momp was identified and characterized from 22 strains of c. jejuni and one strain of c. coli. it was shown that the single-copy cmp locus encoded a protein with character ...200010992471
characterization and expression of hmur, a tonb-dependent hemoglobin receptor of porphyromonas gingivalis.the gram-negative pathogen porphyromonas gingivalis requires hemin for growth. hemoglobin bound to haptoglobin and hemin complexed to hemopexin can be used as heme sources, indicating that p. gingivalis must have a means to remove the hemin from these host iron-binding proteins. however, the specific mechanisms utilized by p. gingivalis for the extraction of heme from heme-binding proteins and for iron transport are poorly understood. in this study we have determined that a newly identified tonb ...200011004172
antibodies, directed towards campylobacter jejuni antigens, in sera from poultry abattoir workers.occupational exposure of susceptible humans to campylobacter jejuni appears to result in resistance to disease. this is believed to be due to acquired protective immunity. to support this hypothesis the levels of c. jejuni-specific igg and igm antibodies were determined in sera from poultry abattoir workers. such individuals are persistently exposed to c. jejuni, but apparently rarely acquire campylobacteriosis. sera from 43 short-term workers (employed < or = 1 month), 78 long-term workers and ...200011012618
evaluation of a pcr primer based on the isocitrate dehydrogenase gene for detection of helicobacter pylori in order to improve detection and identification of helicobacter pylori in highly contaminated samples, we evaluated new specific primers based on the dna base sequence within the isocitrate dehydrogenase (icd) gene to amplify a 1,200-bp dna segment. the specificity of the icd primer was tested against dna derived from various bacteria, including 7 helicobacter species and a panel of 1 gram-variable, 2 gram-positive, and 16 gram-negative bacteria, as well as dna from houseflies and feces from h. ...200011015397
evaluation of phenotypic and genotypic methods for subtyping campylobacter jejuni isolates from humans, poultry, and cattle.six methods for subtyping of campylobacter jejuni were compared and evaluated with a collection of 90 isolates from poultry, cattle, and sporadic human clinical cases as well as from a waterborne outbreak. the applied methods were penner heat-stable serotyping; automated ribotyping (riboprinting); random amplified polymorphic dna typing (rapd); pulsed-field gel electrophoresis (pfge); restriction fragment length polymorphisms of the flagellin gene, flaa (fla-rflp); and denaturing gradient gel el ...200011015406
evaluation of the alexon-trend prospect campylobacter microplate assay.we evaluated stool specimens known to contain or be free of campylobacter by traditional culture, using the prospect campylobacter microplate assay (alexon-trend, ramsey, minn.). this rapid enzyme immunoassay for the detection of campylobacter-specific antigens demonstrated 96% sensitivity and 99% specificity and is an acceptable alternative method of campylobacter detection.200011015419
detection and characterization of autoagglutination activity by campylobacter several gram-negative bacterial pathogens, autoagglutination (aag) activity is a marker for interaction with host cells and virulence. campylobacter jejuni strains also show aag, but this property varies considerably among strains. to examine the characteristics of c. jejuni aag, we developed a quantitative in vitro assay. for strain 81-176, which shows high aag, activity was optimal for cells grown for < or = 24 h, was independent of growth temperature, and was best measured for cells suspen ...200011035721
role of catalase in campylobacter jejuni intracellular survival.the ability of campylobacter jejuni to penetrate normally nonphagocytic host cells is believed to be a key virulence determinant. recently, kinetics of c. jejuni intracellular survival have been described and indicate that the bacterium can persist and multiply within epithelial cells and macrophages in vitro. studies conducted by pesci et al. indicate that superoxide dismutase contributes to intraepithelial cell survival, as isogenic sod mutants are 12-fold more sensitive to intracellular killi ...200011035743
a novel action of the proton pump inhibitor rabeprazole and its thioether derivative against the motility of helicobacter pylori.the motility of helicobacter pylori was maximum at 37 degrees c and at ph 6. a newly developed proton pump inhibitor, rabeprazole (rpz), and its thioether derivative (rpz-th) markedly inhibited the motility of h. pylori. the concentrations of the drug necessary to inhibit 50% of the motility were 0.25, 16, 16, and >64 microgram/ml for rpz-th, rpz, lansoprazole, and omeprazole, respectively. no such inhibitory effects were observed with h(2) blockers or anti-h. pylori agents. the motilities of ca ...200011036024
milkborne campylobacter infection in april 1998, an annual 2-day animal farm sale was held in hódmezóvásárhely, where 500 to 600 visitors consumed unpasteurized milk. the first signs of disease began 2 days after the end of the sale. fifty-two people from a wide age range fell ill, primarily with inflammatory enteritis. these cases included 34 with campylobacter positivity: 30 with campylobacter jejuni and 4 with campylobacter coli. environmental samples (raw milk, udder swabs, and rectal swabs from 12 cows in the suspected herd ...200011041145
genetics of swarming motility in salmonella enterica serovar typhimurium: critical role for lipopolysaccharide.salmonella enterica serovar typhimurium can differentiate into hyperflagellated swarmer cells on agar of an appropriate consistency (0.5 to 0.8%), allowing efficient colonization of the growth surface. flagella are essential for this form of motility. in order to identify genes involved in swarming, we carried out extensive transposon mutagenesis of serovar typhimurium, screening for those that had functional flagella yet were unable to swarm. a majority of these mutants were defective in lipopo ...200011053374
characterization of a novel outer membrane hemin-binding protein of porphyromonas gingivalis.porphyromonas gingivalis is a gram-negative, anaerobic coccobacillus that has been implicated as a major etiological agent in the development of chronic periodontitis. in this paper, we report the characterization of a protein, ihtb (iron heme transport; formerly designated pga30), that is an outer membrane hemin-binding protein potentially involved in iron assimilation by p. gingivalis. ihtb was localized to the cell surface of p. gingivalis by western blot analysis of a sarkosyl-insoluble oute ...200011053391
identification of ciprofloxacin-resistant campylobacter jejuni by use of a fluorogenic pcr assay.fluoroquinolones are one class of antimicrobial agents commonly used to treat severe campylobacter jejuni infection. c. jejuni strains resistant to high levels of the fluoroquinolone ciprofloxacin (mic >/=16 microg/ml) have been predominantly characterized with a c-->t transition in codon 86 of gyra. the gyra gene encodes one subunit of dna gyrase, which is a primary target for fluoroquinolone antibiotics. this study establishes a rapid pcr-based taqman method for identifying ciprofloxacin-resis ...200011060054
genotyping of clinical and chicken isolates of campylobacter jejuni and campylobacter coli.genomic dna from 58 strains of campylobacter made up of 48 campylobacter jejuni and ten campylobacter coli were digested with sma i and analysed by pulsed-field gel electrophoresis (pfge). the cleavage of dna by sma i gave 22 distinct hybridization patterns. the two campylobacter species were subtyped by pfge. the average genomic size for c. jejuni by sma i digestion was 1.73 mb, while that of c. coli gave 1.7 mb. results from this study indicate that pfge analysis by sma i digested genomic dna ...200011077971
campylobacter jejuni cytolethal distending toxin mediates release of interleukin-8 from intestinal epithelial cells of campylobacter jejuni and campylobacter coli can induce release of interleukin-8 (il-8) from int407 cells. additionally, membrane fractions of c. jejuni 81-176, but not membrane fractions of c. coli strains, can also induce release of il-8. membrane preparations from 81-176 mutants defective in any of the three membrane-associated protein subunits of cytolethal distending toxin (cdt) were unable to induce il-8. the presence of the three cdt genes on a shuttle plasmid in trans restor ...200011083762
sialylation of lipooligosaccharide cores affects immunogenicity and serum resistance of campylobacter jejuni.three genes involved in biosynthesis of the lipooligosaccharide (los) core of campylobacter jejuni msc57360, the type strain of the hs:1 serotype, whose structure mimics gm(2) ganglioside, have been cloned and characterized. mutation of genes encoding proteins with homology to a sialyl transferase (cstii) and a putative n-acetylmannosamine synthetase (neuc1), part of the biosynthetic pathway of n-acetylneuraminic acid (neunac), have identical phenotypes. the los cores of these mutants display id ...200011083778
identification of taxonomic and epidemiological relationships among campylobacter species by numerical analysis of aflp profiles.amplified fragment length polymorphism (aflp)-based profiling was performed on 138 strains representing all named campylobacter species and subspecies. profiles of 15/16 species comprised 6 to greater than 100 fragments and were subjected to numerical analysis. the mean similarity of 48 duplicate, outbreak and/or 'identical' strain profiles exceeded 94%. species were clearly distinguished at the 17.90% similarity (s-) level in the dendrogram. subspecies of campylobacter jejuni and campylobacter ...200011094296
detection on surfaces and in caco-2 cells of campylobacter jejuni cells transformed with new gfp, yfp, and cfp marker plasmids.we have developed two sets of campylobacter shuttle vectors containing either the gfp (green fluorescent protein), yfp (yellow fluorescent protein), or cfp (cyan fluorescent protein) reporter gene. in one set, the reporter gene is fused to a consensus campylobacter promoter sequence (p(c)). the other set contains a puc18 multicloning site upstream of the reporter gene, allowing the construction of transcriptional fusions using known promoters or random genomic fragments. c. jejuni cells transfor ...200011097924
purification, characterization and sequence analysis of omp50,a new porin isolated from campylobacter jejuni.a novel pore-forming protein identified in campylobacter was purified by ion-exchange chromatography and named omp50 according to both its molecular mass and its outer membrane localization. we observed a pore-forming ability of omp50 after re-incorporation into artificial membranes. the protein induced cation-selective channels with major conductance values of 50-60 ps in 1 m nacl. n-terminal sequencing allowed us to identify the predicted coding sequence cj1170c from the campylobacter jejuni g ...200011104668
evaluation of a new commercial immunoassay for rapid detection of campylobacter jejuni in stool order to evaluate a new commercial enzyme immunoassay (prospect campylobacter microplate assay; alexon-trend, usa) for the detection of campylobacter jejuni and campylobacter coli in stool samples, 30 faecal specimens known to be culture-positive for campylobacter jejuni were tested with the new assay. the detection limit was approximately 3 x 10(6)/ml in faecal suspensions. the sensitivity relative to culture was 80% (24/30). all of the 24 positive samples, except for one, remained positive ...200011117647
the effect of thermal stress on campylobacter coli.enteropathogenic campylobacter jejuni, camp. coli and camp. lari are currently the most common cause of acute infectious diarrhoeal illness in the uk. many domestic animals, including pigs, act as natural reservoirs for these organisms and infection may occur through the ingestion of contaminated foodstuffs. the safety of locally produced porcine liver was assessed in relation to the heat susceptibility of campylobacter spp. present in eviscerated product.200011119166
comparison of basal broth media for the optimal laboratory recovery of campylobacter jejuni and campylobacter coli.campylobacter species are the most common known bacterial cause of acute diarrhoeal disease and incidences are increasing yearly in ireland. concern is expressed that this increase may be due to poor laboratory techniques in recognising these organisms as they are fastidious and technically demanding to culture.200011272874
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