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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
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
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
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
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
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
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
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
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
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
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
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
drug resistance in campylobacter jejuni, c coli, and c lari isolated from humans in north west england and wales, 1997.to test the sensitivity of strains of campylobacter species isolated from humans in england and wales against a range of antimicrobial agents for the purpose of monitoring therapeutic efficacy and as an epidemiological marker.199910690169
antibiotic resistance in campylobacter strains isolated from animals, foods, and humans in spain in 1997-1998.colonization by campylobacter strains was investigated in human, broiler, and pig fecal samples from 1997-1998, as well as in foods of animal origin, and antibiotic susceptibility testing was carried out for these strains. campylobacter strains were isolated in the foods of animal origin (55 of 101 samples; 54.4%), intestinal samples from broilers (85 of 105; 81%), and pigs (40 of 45; 88.9%). a total of 641 campylobacter strains were isolated from 8,636 human fecal samples of clinical origin (7. ...200010639348
flagellin gene polymorphism analysis of campylobacter compared with antigen serotyping.flagellin gene sequence polymorphisms were used to discriminate amongst 53 strains of campylobacter jejuni and c. coli. the campylobacter strains were made up of forty-three strains of campylobacter jejuni and 10 strains of campylobacter coli. the results were analysed in relation to penner serotyping. twenty dna pcr-rflp patterns (genotypes) were identified by analysis of dde i fragment length polymorphisms in flagellin gene (fla a and fla b) polymerase chain reaction (pcr) products. flagellin ...199910627993
virulent strains of helicobacter pylori demonstrate delayed phagocytosis and stimulate homotypic phagosome fusion in macrophages.helicobacter pylori colonizes the gastric epithelium of approximately 50% of the world's population and plays a causative role in the development of gastric and duodenal ulcers. h. pylori is phagocytosed by mononuclear phagocytes, but the internalized bacteria are not killed and the reasons for this host defense defect are unclear. we now show using immunofluorescence and electron microscopy that h. pylori employs an unusual mechanism to avoid phagocytic killing: delayed entry followed by homoty ...200010620610
isolation and characterization of campylobacter jejuni subsp. jejuni from macaroni penguins (eudyptes chrysolophus) in the subantarctic region.on bird island, south georgia, albatrosses (n = 140), penguins (n = 100), and fur seals (n = 206) were sampled for campylobacter jejuni. c. jejuni subsp. jejuni was recovered from three macaroni penguins (eudyptes chrysolophus). these isolates, the first reported for the subantarctic region, showed low genetic diversity and high similarity to northern hemisphere c. jejuni isolates, possibly suggesting recent introduction to the area.200010618265
genotyping of campylobacter spp. 200010618195
prevalence of campylobacter, arcobacter, helicobacter, and sutterella spp. in human fecal samples as estimated by a reevaluation of isolation methods for campylobacters.the aims of this study were to investigate the prevalence of campylobacteria including campylobacter jejuni subsp. jejuni (c. jejuni) and campylobacter coli in human clinical samples and in samples from healthy individuals and to reevaluate the efficacies of conventional selective methods for isolation of campylobacter spp. two charcoal-based selective media, modified charcoal cefoperazone deoxycholate agar (mccda) and cefoperazone-amphotericin-teicoplanin (cat) agar, were compared with skirrow' ...200010618103
localized reversible frameshift mutation in the flha gene confers phase variability to flagellin gene expression in campylobacter coli.phase variation of flagellin gene expression in campylobacter coli ua585 was correlated with high-frequency, reversible insertion and deletion frameshift mutations in a short homopolymeric tract of thymine residues located in the n-terminal coding region of the flha gene. mutation-based phase variation in flha may generate functional diversity in the host and environment.200010613882
cytolethal distending toxin sequence and activity in the enterohepatic pathogen helicobacter hepaticus.little is known about the molecular pathogenesis of hepatitis and enterocolitis caused by enterohepatic helicobacter species. sonicates of the murine pathogen helicobacter hepaticus were found to cause progressive cell distension, accumulation of filamentous actin, and g(2)/m cell cycle arrest in hela cell monolayers. the genes encoding this cytotoxic activity were cloned from h. hepaticus. three open reading frames with closest homology to cdta, cdtb, and cdtc from campylobacter jejuni were ide ...200010603386
a multifunctional atp-binding cassette transporter system from vibrio cholerae transports vibriobactin and enterobactin.vibrio cholerae uses the catechol siderophore vibriobactin for iron transport under iron-limiting conditions. we have identified genes for vibriobactin transport and mapped them within the vibriobactin biosynthetic gene cluster. within this genetic region we have identified four genes, viup, viud, viug and viuc, whose protein products have homology to the periplasmic binding protein, the two integral cytoplasmic membrane proteins, and the atpase component, respectively, of other iron transport s ...199910601218
helicobacter pylori and neutrophils: sialic acid-dependent binding to various isolated glycoconjugates.helicobacter pylori has been shown to agglutinate erythrocytes in a sialic acid-dependent manner. however, very few studies have examined relevant target cells in the human stomach. neutrophils are required for the onset of gastritis, and the inflammatory reaction may be induced on contact between bacteria and neutrophils. in the present work, glycolipids and glycoproteins were isolated from neutrophils and were studied for binding by overlay with radiolabeled bacteria on thin-layer chromatogram ...199910569742
rapid identification of campylobacter, arcobacter, and helicobacter isolates by pcr-restriction fragment length polymorphism analysis of the 16s rrna gene.a rapid two-step identification scheme based on pcr-restriction fragment length polymorphism (pcr-rflp) analysis of the 16s rrna gene was developed in order to differentiate isolates belonging to the campylobacter, arcobacter, and helicobacter genera. for 158 isolates (26 reference cultures and 132 clinical isolates), specific rflp patterns were obtained and species were successfully identified by this assay.199910565952
large-scale survey of campylobacter species in human gastroenteritis by pcr and pcr-enzyme-linked immunosorbent assay.a pcr-based study of the incidence of enteropathogenic campylobacter infection in humans was done on the basis of a detection and identification algorithm consisting of screening pcrs and species identification by pcr-enzyme-linked immunosorbent assay. this was applied to dna extracted from 3,738 fecal samples from patients with sporadic cases of acute gastroenteritis, submitted by seven regional public health laboratories in england and wales over a 2-year period. the sending laboratories had c ...199910565897
recovery in embryonated eggs of viable but nonculturable campylobacter jejuni cells and maintenance of ability to adhere to hela cells after resuscitation.the existence of a viable but nonculturable (vbnc) state has been described for campylobacter jejuni as it had been for a number pathogenic bacteria. three c. jejuni human isolates were suspended in surface water and subsequently entered the vbnc state. after starvation for 30 days, vbnc cells were inoculated in the yolk sacs of embryonated eggs. culturable cells were detected in a large proportion of the embryonated eggs inoculated with vbnc c. jejuni cells. recovered cells kept their adhesion ...199910543837
molecular characterization of the locus encoding biosynthesis of the lipopolysaccharide o antigen of escherichia coli serotype o113.shiga toxigenic escherichia coli (stec) strains are a diverse group of organisms capable of causing severe gastrointestinal disease in humans. within the stec family, eae-positive stec strains, particularly those belonging to serogroups o157 and o111, appear to have greater virulence for humans. however, in spite of being eae negative, stec strains belonging to serogroup o113 have frequently been associated with cases of severe stec disease, including hemolytic-uremic syndrome (hus). western blo ...199910531250
evaluation of a truncated recombinant flagellin subunit vaccine against campylobacter jejuni.a recombinant protein comprising the maltose-binding protein (mbp) of escherichia coli fused to amino acids 5 to 337 of the flaa flagellin of campylobacter coli vc167 was evaluated for immunogenicity and protective efficacy against challenge by a heterologous strain of campylobacter, campylobacter jejuni 81-176, in two murine models. the sequence of the flaa gene of strain 81-176 revealed a predicted protein which was 98.1% similar to that of vc167 flaa over the region expressed in the fusion pr ...199910531231
routine identification of campylobacter jejuni and campylobacter coli from human stool samples.correct identification of campylobacter jejuni and campylobacter coli isolates to the species or subspecies level is a cumbersome but nevertheless important task for a routine diagnostic laboratory. the widely used biochemical tests might be often misleading while more sophisticated phenotypic or genotypic methods are not generally available. this investigation was performed to assess the performance of common biochemical identification in comparison with species-specific pcr and gas liquid chro ...199910518720
campylobacter jejuni contains two fur homologs: characterization of iron-responsive regulation of peroxide stress defense genes by the perr repressor.expression of the peroxide stress genes alkyl hydroperoxide reductase (ahpc) and catalase (kata) of the microaerophile campylobacter jejuni is repressed by iron. whereas iron repression in gram-negative bacteria is usually carried out by the fur protein, previous work showed that this is not the case in c. jejuni, as these genes are still iron repressed in a c. jejuni fur mutant. an open reading frame encoding a fur homolog (designated perr for "peroxide stress regulator") was identified in the ...199910515927
viability and dna maintenance in nonculturable spiral campylobacter jejuni cells after long-term exposure to low temperatures.survival of campylobacter jejuni at 4 and 20 degrees c was investigated by using cellular integrity, respiratory activity, two-dimensional (2d) protein profile, and intact dna content as indicators of potential viability of nonculturable cells. intact dna content after 116 days, along with cellular integrity and respiring cells, was detected for up to 7 months at 4 degrees c by pulsed-field gel electrophoresis. most changes in 2d protein profiles involved up- or down-regulation.199910508106
phase variation in helicobacter pylori lipopolysaccharide due to changes in the lengths of poly(c) tracts in alpha3-fucosyltransferase genes.the lipopolysaccharide (lps) of helicobacter pylori expresses the lewis x (lex) and/or ley antigen. we have shown previously that h. pylori lps displays phase variation whereby an lex-positive strain yields variants with different lps serotypes, for example, lex plus ley or nonfucosylated polylactosamine. h. pylori has two alpha3-fucosyltransferase genes that both contain poly(c) tracts. we now demonstrate that these tracts can shorten or lengthen randomly, which results in reversible frameshift ...199910496917
the absence of cecal colonization of chicks by a mutant of campylobacter jejuni not expressing bacterial fibronectin-binding protein.campylobacter jejuni is a common cause of human gastrointestinal illness throughout the world. infections with c. jejuni and campylobacter coli are frequently acquired by eating undercooked chicken. the ability of c. jejuni to become established in the gastrointestinal tract of chickens is believed to involve binding of the bacterium to the gastrointestinal surface. a 37-kd outer membrane protein, termed cadf, has been described that facilitates the binding of campylobacter to fibronectin. this ...199910494431
specific pcr identification and differentiation of the thermophilic campylobacters, campylobacter jejuni, c. coli, c. lari, and c. upsaliensis.a sensitive pcr assay that detects the thermophilic campylobacters c. jejuni, c. coli, c. lari, and c. upsaliensis is reported. furthermore, by digestion of the pcr products with two restriction enzymes, species differentiation was demonstrated. thus, the present method has the potential to be used for both detection and identification of thermophilic campylobacter species.199910488210
ciprofloxacin resistance in campylobacter jejuni isolates: detection of gyra resistance mutations by mismatch amplification mutation assay pcr and dna sequence analysis.the gyra quinolone resistance determining region was sequenced from 13 ciprofloxacin-resistant and 20 ciprofloxacin-susceptible campylobacter jejuni isolates. all isolates resistant to ciprofloxacin had thr-86-to-ile mutations, a mutation frequently associated with the acquisition of resistance to fluoroquinolones. a mismatch amplification mutation assay (mama) pcr protocol was developed that detects this gyra mutation in quinolone-resistant isolates. the mama pcr provides a means for routine de ...199910488192
amplified-fragment length polymorphism analysis: the state of an art. 199910488158
phage typing of campylobacter jejuni and campylobacter coli and its use as an adjunct to serotyping.campylobacter is the most commonly reported cause of gastro-intestinal infection in england and wales, with over 50,000 reported cases in 1997. the majority of human campylobacter isolates in england and wales are c. jejuni (c. 90%) with most of the remainder being c. coli. we describe the use of phage typing as an extension to serotyping for more detailed characterization within these two species. the scheme was piloted during a study of 2407 c. jejuni and 182 c. coli strains isolated in wales ...199910487641
recombinant single-chain fv antibody fragment-alkaline phosphatase conjugate for one-step immunodetection in molecular hybridization.using phage-display technology, a recombinant single-chain fv antibody fragment (scfv) was rapidly generated from the k16-16 hybridoma secreting mouse monoclonal antibody (mab) that binds to acetylaminofluorene-labeled dna (aaf-dna). the selected a4 phage-scfv specifically bound to aaf-dna. the anti-aaf scfv gene was then recloned into a fusion vector for the production of a hybrid protein comprising the antibody fragment fused to a potent bacterial alkaline phosphatase variant (phoav). the anti ...199910485265
the c-terminal domain of the bordetella pertussis autotransporter brka forms a pore in lipid bilayer membranes.brka is a 103-kda outer membrane protein of bordetella pertussis that mediates resistance to antibody-dependent killing by complement. it is proteolytically processed into a 73-kda n-terminal domain and a 30-kda c-terminal domain as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. brka is also a member of the autotransporter family of proteins. translocation of the n-terminal domain of the protein across the outer membrane is hypothesized to occur through a pore formed by ...199910482528
hp0333, a member of the dpra family, is involved in natural transformation in helicobacter pylori.helicobacter pylori is naturally competent for dna transformation, but the mechanism by which transformation occurs is not known. for haemophilus influenzae, dpra is required for transformation by chromosomal but not plasmid dna, and the complete genomic sequence of h. pylori 26695 revealed a dpra homolog (hp0333). examination of genetic databases indicates that dpra homologs are present in a wide variety of bacterial species. to examine whether hp0333 has a function similar to dpra of h. influe ...199910482496
metabolism and genetics of helicobacter pylori: the genome era.the publication of the complete sequence of helicobacter pylori 26695 in 1997 and more recently that of strain j99 has provided new insight into the biology of this organism. in this review, we attempt to analyze and interpret the information provided by sequence annotations and to compare these data with those provided by experimental analyses. after a brief description of the general features of the genomes of the two sequenced strains, the principal metabolic pathways are analyzed. in particu ...199910477311
sulfonamide resistance in clinical isolates of campylobacter jejuni: mutational changes in the chromosomal dihydropteroate synthase.the characterization of the genetic basis of sulfonamide resistance in campylobacter jejuni was attempted. the resistance determinant from a sulfonamide-resistant strain of c. jejuni was cloned and was found to show 42% identity with the folp gene (which codes for dihydropteroate synthase, the target of sulfonamides) of the related bacterium helicobacter pylori. the sequences of the areas surrounding the folp gene in c. jejuni showed similarity to those of the areas surrounding the corresponding ...199910471557
direct analysis and identification of helicobacter and campylobacter species by maldi-tof mass spectrometry.campylobacter jejuni, campylobacter fetus, and campylobacter coli were compared with helicobacter pylori and helicobacter mustelae by direct analysis of individual cultured colonies in 50% methanol-water with a matrix-assisted laser desorption/ionization time-of-flight mass spectrometer (maldi-tof ms). h. pylori and campylobacter species from blood agar culture produced unique, complex spectra with over 25 different ions in mass/charge (m/z) range from 2,000 to 62,000. a biomarker for h. pylori ...199910464475
an iron-regulated alkyl hydroperoxide reductase (ahpc) confers aerotolerance and oxidative stress resistance to the microaerophilic pathogen campylobacter jejuni.microaerophiles like campylobacter jejuni must resist oxidative stresses during transmission or infection. growth of c. jejuni 81116 under iron limitation greatly increased the expression of two polypeptides of 26 and 55 kda. the identification of these proteins by n-terminal amino acid sequencing showed both to be involved in the defense against oxidative stress. the 55-kda polypeptide was identical to c. jejuni catalase (kata), whereas the n terminus of the 26-kda polypeptide was homologous to ...199910438747
incidence of salmonella, campylobacter jejuni, campylobacter coli, and listeria monocytogenes in poultry carcasses and different types of poultry products for sale on the belgian retail market.from january 1997 to may 1998, 772 samples of poultry carcasses and poultry products for sale on the retail market in belgium were analyzed for the presence of salmonella spp., salmonella enteritidis, campylobacter jejuni, c. coli, and listeria monocytogenes per 100 cm2 or 25 g. poultry samples were contaminated with salmonella (36.5%), c. jejuni and c. coli (28.5%), and l. monocytogenes (38.2%). in about 12.3% of the poultry samples, the l. monocytogenes contamination level exceeded 1 cfu per g ...199910419264
occurrence, removal and seasonal variation of thermophilic campylobacters and arcobacter in sewage sludge.the presence of thermophilic campylobacters and arcobacter was investigated in four types of sewage sludge taken from the treatment plant in bologna (italy): primary, activated, thickened and anaerobically digested sludge. campylobacter jejuni and campylobacter coli were more numerous during the march-september period and were found only in primary sludge (22.7%) with mean counts of 278 mpn/g dry matter and 1403 mpn/g dry matter respectively. arcobacter butzleri were found in all types of sludge ...199910418097
campylobacter jejuni 81-176 associates with microtubules and dynein during invasion of human intestinal cells.campylobacter jejuni uptake into cultured int407 cells was analyzed kinetically over a wide range of starting multiplicities of infection (moi; from 0.02 to 20,000 bacteria/epithelial cell). the efficiency of internalization was the highest at moi of 0.02 and decreased steadily at higher mois, presumably due to reported c. jejuni autoagglutination at higher densities. total internalized campylobacter cfu increased gradually from an moi of 0.02 to a peak at an moi of 200 (reaching an average of t ...199910417189
identification of a glycoprotein produced by enterotoxigenic escherichia coli.enterotoxigenic escherichia coli (etec) strain h10407 is capable of invading epithelial cell lines derived from the human ileocecum and colon in vitro. two separate chromosomally encoded invasion loci (tia and tib) have been cloned from this strain. these loci direct nonadherent and noninvasive laboratory strains of e. coli to adhere to and invade cultured human intestinal epithelial cells. the tib locus directs the synthesis of tiba, a 104-kda outer membrane protein that is directly correlated ...199910417177
rapid detection, by pcr and reverse hybridization, of mutations in the helicobacter pylori 23s rrna gene, associated with macrolide resistance.a pcr-based reverse hybridization system (research prototype kit inno-lipa for h. pylori resistance) was developed and evaluated for simultaneous detection of 23s ribosomal dna point mutations, associated with macrolide resistance in helicobacter pylori. fifty-seven h. pylori strains (51 natural, 6 laboratory-derived artificial, 52 resistant, and 5 susceptible strains) were tested by pcr-lipa (detecting mutations a2115-->g, g2141-->a, a2142-->g, a2142-->c, a2143-->g, a2143-->c, and a2143-->t), d ...199910390244
evaluation of the effect of temperature and nutrients on the survival of campylobacter spp. in water microcosms.batch microcosms containing various water types (de-ionized and river water with or without sediment), incubated at a range of temperatures (5-37 degrees c), were used to facilitate a comparative evaluation of the significance of such variables and their interactions upon the collective and individual survival of four species of thermophilic campylobacter. all variables significantly influenced (p < = 0.031) population decay rates. minimal decay for the group was identified at low temperatures ( ...199910389249
in-vitro activity of moxifloxacin against fluoroquinolone-resistant strains of aerobic gram-negative bacilli and enterococcus faecalis.mics of the new fluoroquinolone, moxifloxacin, and those of ciprofloxacin, ofloxacin and sparfloxacin for 19 genetically characterized fluoroquinolone-resistant strains were determined by the agar dilution method. the mics of moxifloxacin for escherichia isolates with one mutation in gyra (corresponding to ser83-->leu or asp87-->gly substitution) were 0.25-0.5 mg/l, while those of ciprofloxacin, ofloxacin and sparfloxacin were 0.06-0.25, 1 and 0.12-0.5 mg/l, respectively. these values were four- ...199910382871
campylobacter coli strains with enlarged flagellin genes isolated from river water.a group of campylobacters isolated from river water were found to possess unusually large flagellin genes. both phenotype and serology were consistent with identification as campylobacter coli. phylogenetic analysis of small (16s, rrs) and large subunit (23s, rrl) rrna genes of a representative strain, nctc 13006, demonstrated high levels of relatedness with c. jejuni and c. coli (99.1 and 98.3% similarity for 16s; 99.3 and 99.4% similarity for 23s). large flagellin proteins were demonstrated by ...199910376486
evaluation of the anaeropack campylo system for growth of microaerophilic bacteria.growth of microaerophilic bacteria in the anaeropack campylo (mitsubishi gas chemical america, inc., new york, n.y.) atmosphere generation system was compared to growth in the campypak plus jar and campypak pouch (becton-dickinson microbiology systems [bdms], cockeysville, md.). growth in the anaeropack campylo system was considered equivalent to or better than growth obtained in the campypak plus and campypak pouch systems for 48 of the 50 helicobacter pylori strains and for all 28 campylobacte ...199910364622
nomenclature for new tetracycline resistance determinants.letters of the english alphabet have heretofore been used to name tetracycline resistance determinants. since all 26 letters have now been used, a nomenclature employing numerals is recommended for future determinants, and one laboratory has offered to coordinate the assignment of numerals.199910348788
generation of a superoxide dismutase (sod)-deficient mutant of campylobacter coli: evidence for the significance of sod in campylobacter survival and colonization.the microaerophilic nature of campylobacter species implies an inherent sensitivity towards oxygen and its reduction products, particularly the superoxide anion. the deleterious effects of exposure to superoxide radicals are counteracted by the activity of superoxide dismutase (sod). we have shown previously that campylobacter coli possesses an iron cofactored sod. the sodb gene of c. coli ua585 was insertionally inactivated by the site-specific insertion of a teto cassette. organisms harboring ...199910347040
high-resolution genotyping of campylobacter strains isolated from poultry and humans with amplified fragment length polymorphism fingerprinting.for epidemiological studies of campylobacter infections, molecular typing methods that can differentiate campylobacters at the strain level are needed. in this study we used a recently developed genotyping method, amplified fragment length polymorphism (aflp), which is based on selective amplification of restriction fragments of chromosomal dna, for genetic typing of campylobacter jejuni and campylobacter coli strains derived from humans and poultry. we developed an automated aflp fingerprinting ...199910347015
biotin-streptavidin enzyme-linked immunosorbent assay for the detection of antibodies to campylobacter jejuni and c. coli in chickens.an enzyme-linked immunosorbent assay (elisa) was developed in a homologous system with bacterial ultrasonic-treated proteins as the antigen and antisera from chickens infected orally and subcutaneously with the strain campylobacter jejuni serovar 6 (cj 6). the cut-off level was determined using antisera from non-infected specific-pathogen-free chickens up to the age of 10 weeks. the suitability of the elisa system was verified using antisera taken from chickens orally infected at the age of 4 we ...199910337238
passive immunity against human pathogens using bovine antibodies. 199910337007
septic shock due to helicobacter fennelliae in a non-human immunodeficiency virus-infected heterosexual patient.helicobacter fennelliae (formerly campylobacter fennelliae) has been reported to cause bacteremia in homosexual men with or without human immunodeficiency virus (hiv) infection. we report here a 48-year-old, non-hiv-infected, heterosexual man with diabetes mellitus and cirrhosis of the liver who developed bacteremia and septic shock due to h. fennelliae. the patient was treated successfully initially with intravenous ampicillin-sulbactam and ceftazidime, followed by ampicillin-sulbactam only. th ...199910325388
differentiation of helicobacter pylori isolates based on lectin binding of cell extracts in an agglutination assay.plant and animal lectins with various carbohydrate specificities were used to type 35 irish clinical isolates of helicobacter pylori and the type strain nctc 11637 in a microtiter plate assay. initially, a panel of eight lectins with the indicated primary specificities were used: anguilla anguilla (aaa), lotus tetragonolobus (lotus a), and ulex europaeus i (uea i), specific for alpha-l-fucose; solanum tuberosum (sta) and triticum vulgaris (wga), specific for beta-n-acetylglucosamine; glycine max ...199910325361
rapid identification of thermotolerant campylobacter jejuni, campylobacter coli, campylobacter lari, and campylobacter upsaliensis from various geographic locations by a gtpase-based pcr-reverse hybridization assay.recently, a gene from campylobacter jejuni encoding a putative gtpase was identified. based on two semiconserved gtp-binding sites encoded within this gene, pcr primers were selected that allow amplification of a 153-bp fragment from c. jejuni, c. coli, c. lari, and c. upsaliensis. sequence analysis of these pcr products revealed consistent interspecies variation, which allowed the definition of species-specific probes for each of the four thermotolerant campylobacter species. multiple probes we ...199910325325
study of the presence of campylobacter jejuni and c. coli in sand samples from four swiss chicken farms.chicken farms are frequently infected with campylobacter jejuni and campylobacter coli. the objective of the present study was to investigate environmental samples from chicken farms for the presence of c. jejuni and c. coli. every week between july and november 1997, three sand samples from the runs of four chicken farms were analyzed by culture and directly by polymerase chain reaction (pcr). these two detection methods were compared to each other. a total of 231 samples were tested. eleven sa ...199910229951
identification of virulence genes of helicobacter pylori by random insertion mutagenesis.the complete genome of the gram-negative bacterial pathogen helicobacter pylori, an important etiological agent of gastroduodenal disease in humans, has recently been published. this sequence revealed that the putative products of roughly one-third of the open reading frames (orfs) have no significant homology to any known proteins. to be able to analyze the functions of all orfs, we constructed an integration plasmid for h. pylori and used it to generate a random mutant library in this organism ...199910225906
stability of related human and chicken campylobacter jejuni genotypes after passage through chick intestine studied by pulsed-field gel electrophoresis.the genomic stability of 12 campylobacter jejuni strains consisting of two groups of human and chicken isolates was studied by analysis of their pfge (pulsed-field gel electrophoresis) patterns after passage through newly hatched chicks' intestines. the patterns of smai, sali, and sacii digests remained stable after intestinal passage, except for those of two strains. one originally human strain, fb 6371, changed its genotype from ii/a (smai/sacii) to i/b. another strain, bti, originally isolate ...199910224037
cloning and characterization of polyphosphate kinase and exopolyphosphatase genes from pseudomonas aeruginosa 8830.pseudomonas aeruginosa accumulates polyphosphates in response to nutrient limitations. to elucidate the function of polyphosphate in this microorganism, we have investigated polyphosphate metabolism by isolating from p. aeruginosa 8830 the genes encoding polyphosphate kinase (ppk) and exopolyphosphatase (ppx), which are involved in polyphosphate synthesis and degradation, respectively. the 690- and 506-amino-acid polypeptides encoded by the two genes have been expressed in escherichia coli and p ...199910224002
high-resolution genomic fingerprinting of campylobacter jejuni and campylobacter coli by analysis of amplified fragment length polymorphisms.a method for high-resolution genomic fingerprinting of the enteric pathogens campylobacter jejuni and campylobacter coli, based on the determination of amplified fragment length polymorphism, is described. the potential of this method for molecular epidemiological studies of these species is evaluated with 50 type, reference, and well-characterised field strains. amplified fragment length polymorphism fingerprints comprised over 60 bands detected in the size range 35-500 bp. groups of outbreak s ...199910220884
ferric enterobactin binding and utilization by neisseria gonorrhoeae.feta, formerly designated frpb, an iron-regulated, 76-kda neisserial outer membrane protein, shows sequence homology to the tonb-dependent family of receptors that transport iron into gram-negative bacteria. although feta is commonly expressed by most neisserial strains and is a potential vaccine candidate for both neisseria gonorrhoeae and neisseria meningitidis, its function in cell physiology was previously undefined. we now report that feta functions as an enterobactin receptor. n. gonorrhoe ...199910217784
survival times of campylobacter coli in sterilized buffalo milk.the survival level of five campylobacter coli strains isolated from bovine faeces was studied in sterilized buffalo milk kept at 4 degrees c under aerobic conditions. all strains died between 21 and 30 h of storage.199910216458
the use of hipo, encoding benzoylglycine amidohydrolase (hippuricase), as a reporter of gene expression in campylobacter coli.a novel integrative promoter probe vector which utilizes the campylobacter jejuni hipo gene as a reporter of gene expression was developed as a genetic tool in campylobacter coli. the utility of the system was demonstrated by coupling expression of the hipo reporter to the promoters of flaa, flab and kata. subsequently, expression of these genes could be monitored accurately from chromosomally-borne transcriptional fusions using a simple non-destructive colorimetric assay. the system should serv ...199910212441
differentiation of campylobacter coli and c. jejuni by length and dna sequence of the 16s-23s rrna internal spacer region.the internal spacer region (isr) between the 16s and 23s rrna genes of campylobacter was investigated by pcr fragment length typing and dna sequencing of clinical and chicken wild-type isolates. pcr fragment length typing showed one fragment of 859 nt in length for the 12 strains of campylobacter coli investigated. thirty-six of the campylobacter jejuni subsp. jejuni strains possessed one fragment, which varied in size between 727 and 802 nt. three strains showed two fragments between 501 and 92 ...199910206715
cytolethal distending toxin genes in campylobacter jejuni and campylobacter coli isolates: detection and analysis by pcr.campylobacter jejuni produces a toxin called cytolethal distending toxin (cdt). knowledge of the prevalence and homogeneity of campylobacter sp. cdt genes is incomplete. in this work, we identified four pcr primer pairs that collectively amplified cdt genes in all of the c. jejuni and campylobacter coli strains tested. restriction analyses of the cdt pcr products showed clear differences between the cdt genes of these two species, yet there were few heterogeneities noted between members of the s ...199910203548
detection of small numbers of campylobacter jejuni and campylobacter coli cells in environmental water, sewage, and food samples by a seminested pcr assay.a rapid and sensitive assay was developed for detection of small numbers of campylobacter jejuni and campylobacter coli cells in environmental water, sewage, and food samples. water and sewage samples were filtered, and the filters were enriched overnight in a nonselective medium. the enrichment cultures were prepared for pcr by a rapid and simple procedure consisting of centrifugation, proteinase k treatment, and boiling. a seminested pcr based on specific amplification of the intergenic sequen ...199910103261
detection of cytolethal distending toxin activity and cdt genes in campylobacter spp. isolated from chicken carcasses.this study was designed to determine whether isolates from chicken carcasses, the primary source of campylobacter jejuni and campylobacter coli in human infections, commonly carry the cdt genes and also whether active cytolethal distending toxin (cdt) is produced by these isolates. campylobacter spp. were isolated from all 91 fresh chicken carcasses purchased from local supermarkets. campylobacter spp. were identified on the basis of both biochemical and pcr tests. of the 105 isolates, 70 (67%) ...199910103243
fluoroquinolone resistance in salmonellas and campylobacters from humans. 199910102879
serotypes and typability of campylobacter jejuni and campylobacter coli isolated from poultry products.campylobacter infection is one of the most common bacterial enteric pathogens. campylobacter jejuni and campylobacter coli infections are mostly food- and waterborne and especially poultry is often assumed to be an important source. the heat-stable serotyping system (the 'penner' scheme) was used to study the serotype distribution of c. jejuni and c. coli isolated from different food products of poultry origin sampled from retail outlets in denmark. a total of 156 isolates were serotyped, 85% of ...199910100900
mutational analysis of the vaca promoter provides insight into gene transcription in helicobacter pylori.analysis of 12 helicobacter pylori promoters indicates the existence of a consensus -10 hexamer (tataat) but little conservation of -35 sequences. in this study, mutations in either the h. pylori vaca -10 region or the -35 region resulted in decreased vaca transcription and suggested that an extended -10 motif is utilized. thus, despite the lack of a -35 consensus sequence for h. pylori promoters, the -35 region plays a functional role in vaca transcription.199910094707
evaluation of accuracy and repeatability of identification of food-borne pathogens by automated bacterial identification systems.the performances of five automated microbial identification systems, relative to that of a reference identification system, for their ability to accurately and repeatedly identify six common food-borne pathogens were assessed. the systems assessed were the microlog system (biolog inc., hayward, calif.), the microbial identification system (mis; midi inc., newark, del.), the vitek system (biomérieux vitek, hazelwood, mo.), the microscan walkaway 40 system (dade-microscan international, west sacra ...199910074506
comparison of flagellin genes from clinical and environmental pseudomonas aeruginosa isolates.pseudomonas aeruginosa, an important opportunistic pathogen, was isolated from environmental samples and compared to clinically derived strains. while p. aeruginosa was isolated readily from an experimental mushroom-growing unit, it was found only rarely in other environmental samples. a flagellin gene pcr-restriction fragment length polymorphism analysis of the isolates revealed that environmental and clinical p. aeruginosa strains are not readily distinguishable. the variation in the central r ...199910049879
inducing enterotoxigenic properties in campylobacter jejuni and campylobacter coli by serial intraperitoneal passage in mice. 199910029919
characterization of human bactericidal antibodies to bordetella pertussis.the bordetella pertussis brka protein protects against the bactericidal activity of complement and antibody; however, some individuals mount an immune response that overcomes this bacterial defense. to further characterize this process, the bactericidal activities of sera from 13 adults with different modes of exposure to b. pertussis (infected as adults, occupational exposure, immunized with an acellular vaccine, or no identified exposure) against a wild-type strain and a brka complement-sensit ...199910024590
rapid detection of the chlamydiaceae and other families in the order chlamydiales: three pcr tests.few identification methods will rapidly or specifically detect all bacteria in the order chlamydiales, family chlamydiaceae. in this study, three pcr tests based on sequence data from over 48 chlamydial strains were developed for identification of these bacteria. two tests exclusively recognized the chlamydiaceae: a multiplex test targeting the ompa gene and the rrna intergenic spacer and a taqman test targeting the 23s ribosomal dna. the multiplex test was able to detect as few as 200 inclusion ...19999986815
identification of the enteropathogens campylobacter jejuni and campylobacter coli based on the cadf virulence gene and its product.campylobacter jejuni and campylobacter coli are common causes of gastroenteritis in humans. infection with c. jejuni or c. coli is commonly acquired by eating undercooked chicken. the goal of this study was to develop specific detection assays for c. jejuni and c. coli isolates based on the cadf virulence gene and its product. the cadf gene from c. jejuni and c. coli encodes a 37-kda outer membrane protein that promotes the binding of these pathogens to intestinal epithelial cells. a fragment of ...19999986804
pcr-enzyme-linked immunosorbent assay for detection and identification of campylobacter species: application to isolates and stool samples.we report a pcr-enzyme-linked immunosorbent assay which identifies campylobacter species by capture hybridization of a single-stranded 16s rrna gene amplicon with species-specific probes in a microtiter plate format. specificities were confirmed for both reference and field strains, but the type strain of campylobacter coli was atypical. the assay was rapid, informative, and usable with stool-extracted dna.19999889235
motility of helicobacter pylori is coordinately regulated by the transcriptional activator flgr, an ntrc homolog.sigma54 is the subunit of bacterial rna polymerase that transcribes from promoters with enhancer elements bound by enhancer-binding proteins. by computer searches of helicobacter pylori genomic sequences, chromosomal gene disruption, and rna analyses, we have identified sigma54-recognized promoters that regulate transcription of flagellar basal body and hook genes, as well as the enhancer-binding protein flgr (flagellum regulator), a transactivating protein of the ntrc family. we demonstrate tha ...19999882675
antiseptics and disinfectants: activity, action, and resistance.antiseptics and disinfectants are extensively used in hospitals and other health care settings for a variety of topical and hard-surface applications. a wide variety of active chemical agents (biocides) are found in these products, many of which have been used for hundreds of years, including alcohols, phenols, iodine, and chlorine. most of these active agents demonstrate broad-spectrum antimicrobial activity; however, little is known about the mode of action of these agents in comparison to ant ...19999880479
a case control study of potential enteric pathogens for calves raised in cow-calf herds.a matched case control study was performed to describe the epidemiological features of potential enteric pathogens for calves reared in 53 cow-calf herds located in western switzerland. a total of 106 diarrhoeic calves and 126 healthy control calves were collected, all calves were less than 4 months old. faecal samples were analysed for presence of infectious agents related to calf diarrhoea including enterotoxigenic e. coli, verotoxin producing e. coli (vtec), campylobacter sp., yersinia sp., s ...19989852767
effect of low-osmolality nutrient media on growth and culturability of campylobacter species.the growth and culturability of campylobacter jejuni nctc 11351 and other campylobacters were examined in media having different osmolalities at a range of temperatures (4, 25, and 42 degreesc). the medium osmolalities used ranged from the osmolality of full-strength nutrient medium (modified campylobacter broth having an osmolality of around 254 mosmol) down to 96 mosmol. the following two methods were used to produce media having different osmolalities: dilution of the nutrient medium with dis ...19989835543
rapid emergence of high-level resistance to quinolones in campylobacter jejuni associated with mutational changes in gyra and parc.quinolone resistance in clinical isolates of campylobacter jejuni in sweden increased more than 20-fold at the beginning of the 1990s. resistance to 125 microgram of ciprofloxacin per ml in clinical isolates was associated with chromosomal mutations in c. jejuni leading to a thr-86-ile substitution in the gyra product and a arg-139-gln substitution in the parc product.19989835526
high-level resistance to trimethoprim in clinical isolates of campylobacter jejuni by acquisition of foreign genes (dfr1 and dfr9) expressing drug-insensitive dihydrofolate reductases.the pathogenic bacterium campylobacter jejuni has been regarded as endogenously resistant to trimethoprim. the genetic basis of this resistance was characterized in two collections of clinical isolates of c. jejuni obtained from two different parts of sweden. the majority of these isolates were found to carry foreign dfr genes coding for resistant variants of the dihydrofolate reductase enzyme, the target of trimethoprim. the resistance genes, found on the chromosome, were dfr1 and dfr9. in abou ...19989835491
cloning, sequencing, and characterization of the lipopolysaccharide biosynthetic enzyme heptosyltransferase i gene (waac) from campylobacter jejuni and campylobacter coli.campylobacter jejuni and campylobacter coli are common causes of gastrointestinal disease and a proportion of c. jejuni infections have been shown to be associated with the guillain-barré syndrome. the waac gene from campylobacter coli, involved in lipopolysaccharide core biosynthesis, was cloned by complementation of a heptose-deficient strain of salmonella typhimurium, as judged by novobiocin sensitivity, lipopolysaccharide (lps)-specific phage sensitivity, and polyacrylamide-resolved lipopoly ...19989831648
deletion of the major proteolytic site of the helicobacter pylori cytotoxin does not influence toxin activity but favors assembly of the toxin into hexameric structures.the helicobacter pylori cytotoxin is proteolytically cleaved at a flexible hydrophilic loop into two subunits. deletion of the loop sequences had no effect on biological activity of the toxin in the hela cell vacuolation assay but favored the organization of the protein into hexameric rather than heptameric structures.19989784571
a reverse transcriptase polymerase chain reaction assay for the detection of thermophilic campylobacter spp.a novel method was developed for the detection of thermophilic enteropathogenic campylobacters based on the detection of mrna using the reverse transcriptase polymerase chain reaction (rt-pcr). the rna extraction method, dnase treatment and rt-pcr assay were shown to be specific for mrna. the assay is specific for the thermophilic campylobacters campylobacter jejuni, campylobacter coli and campylobacter upsaliensis and restriction fragment length polymorphism (rflp) analysis of the 256 bp amplif ...19989778457
detection of point mutations associated with resistance of helicobacter pylori to clarithromycin by hybridization in liquid phase.when the standard procedure for determining antibiotic susceptibility of bacteria is used, the results are delayed, especially for bacteria that grow slowly, such as helicobacter pylori. treatment for this bacterium may involve clarithromycin, a compound for which resistance has been associated with point mutations on the 23s rrna gene. this resistance is currently found in organisms isolated from 0 to 15% of patients and jeopardizes the success of the treatment. we have designed a test involvin ...19989774580
[relapsing campylobacter coli bacteremia in a hypogammaglobulinemic patient]. 19989767813
iron-responsive gene regulation in a campylobacter jejuni fur mutant.the expression of iron-regulated systems in gram-negative bacteria is generally controlled by the fur protein, which represses the transcription of iron-regulated promoters by using fe2+ as a cofactor. mutational analysis of the campylobacter jejuni fur gene was carried out by generation of a set of mutant copies of fur which had a kanamycin or chloramphenicol resistance gene introduced into the regions encoding the n and c termini of the fur protein. the mutated genes were recombined into the c ...19989765558
use of a selective medium and a membrane filter method for isolation of campylobacter species from spanish paediatric patients.a study was conducted to assess the value of a combination of two culture methods for isolation of campylobacter spp. from spanish children. seven hundred twenty-nine diarrhoeal stool specimens from 599 patients were examined for campylobacter spp. by culturing them on charcoal cefoperazone deoxycholate agar and on blood agar with a membrane filter. one hundred sixteen campylobacter strains were isolated from a total of 108 specimens; 75 (64.6%) were campylobacter jejuni, 32 (27.5%) were campylo ...19989764551
effective recovery of bacterial dna and percent-guanine-plus-cytosine-based analysis of community structure in the gastrointestinal tract of broiler chickens.a dna-based, direct method for initial characterization of the total bacterial community in ileum and cecum of the chicken gastrointestinal (gi) tract was developed. the efficiencies of bacterial extraction and lysis were >95 and >99%, respectively, and therefore the dna recovered should accurately reflect the bacterial communities of the ileal and cecal digesta. total bacterial dna samples were fractionated according to their percent g+c content. the profiles reflecting the composition of the b ...19989758849
physiological activity of campylobacter jejuni far below the minimal growth temperature.the behavior of campylobacter jejuni at environmental temperatures was examined by determining the physiological activities of this human pathogen. the minimal growth temperatures were found to be 32 and 31 degrees c for strains 104 and atcc 33560, respectively. both strains exhibited a sudden decrease in growth rate from the maximum to zero within a few degrees not only near the maximal growth temperature but also near the minimal growth temperature. this could be an indication that a temperatu ...19989758819
identification of a gene encoding a methyl-accepting chemotaxis-like protein form campylobacter coli and its use in a molecular typing scheme for campylobacters.using pcr amplification with degenerate primers, a gene (tlpa) form campylobacter coli encoding a putative 63x0 kda polypeptide which exhibited significant identity with bacterial methyl-accepting chemotaxis proteins (mcps) was identified. a mutant containing an inactivated copy of the tlpa a gene showed a wild-type chemotactic response to all of the chemo-attractants tested. a dna probe based on the highly conserved domain (hcd) of tlpa revealed the presence of multiple copies of genes encoding ...19989750306
nucleotide sequence and characterization of cdra, a cell division-related gene of helicobacter pylori.we identified cell division-related gene cdra in helicobacter pylori hpk5. the putative gene product, cdra, is a 367-amino-acid polypeptide that exhibited a high level of homology to conserved hypothetical atp-binding protein hp0066 of h. pylori 26695, except in the n-terminal region, and showed some similarity to the ftsk/spoiiie family proteins. we isolated a cdra-disrupted mutant by allelic exchange mutagenesis. because of the low transformation frequency, the possibility that a suppressing m ...19989748467
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