construction and characterization of an isogenic urease-negative mutant of helicobacter mustelae.helicobacter mustelae infects the ferret stomach and provides an opportunity to study pathogenic determinants of a helicobacter species in its natural host. we constructed an isogenic urease-negative mutant of h. mustelae which produced no detectable urease and showed a reduced acid tolerance. this mutant provides an opportunity to further evaluate the role of urease in the pathogenesis of helicobacter infection.19957642313
inability of an isogenic urease-negative mutant stain of helicobacter mustelae to colonize the ferret stomach.eight ferrets specific-pathogen-free for helicobacter mustelae were given, per dose, approximately 3.0 x 10(7) cfu of either the wild-type parent strain of h. mustelae (nctc 12032) (two ferrets) the isogenic urease-negative mutant strain of h. mustelae (10::tn3km) (four ferrets), or sterile culture broth (two ferrets). infection status was monitored by endoscopic gastric biopsy for urease activity, histopathology, and culture and by serology at 3, 6, 10, and 21 weeks. all ferrets were necropsied ...19957642314
cellular fatty acid composition of campylobacter pylori from primates and ferrets compared with those of other campylobacters.the cellular fatty acid profiles of newly described campylobacters were determined on a polar, capillary column. six isolates of the gastric spiral organism, campylobacter pylori subsp. mustelae, from ferrets from australia, england, and the united states were all found to have a similar fatty acid profile which was different from that of c. pylori from humans; c. pylori subsp. mustelae did not have 3-hydroxyoctadecanoic acid (3-oh c18:0) and had much less tetradecanoic acid (c14:0) and much mor ...19892745703
characterization of strains of helicobacter pylori: one-dimensional sds-page as a molecular epidemiologic linear sodium dodecyl sulfate-polyacrylamide gel electrophoresis of total proteins, coupled with a computerized numerical analysis, was used to distinguish among strains of helicobacter pylori. one hundred seventy-five clinical strains and five reference strains of h. pylori from humans, four isolates of helicobacter mustelae from ferrets, and three isolates of h. pylori-like organisms (hplos) from miniature swine were examined. intraspecies and interspecies comparisons were made ...19911925314
use of dna restriction endonuclease digest and ribosomal rna gene probe patterns to fingerprint helicobacter pylori and helicobacter mustelae isolated from human and animal hosts.variation amongst strains of helicobacter pylori and helicobacter mustelae was examined by dna restriction endonuclease digestion and rrna gene patterns generated using a non-radioactive probe. chromosomal dna was extracted from 30 cultures of h. pylori from human, rhesus monkey and pig gastric mucosa, and from three h. mustelae isolates from ferret gastric mucosa. dna fingerprinting with hae iii and hind iii showed h. mustelae was relatively homogeneous but revealed genomic heterogeneity within ...19901698260
helicobacter mustelae and helicobacter pylori bind to common lipid receptors in vitro.helicobacter pylori is a recently recognized human pathogen causing chronic-active gastritis in association with duodenal ulcers and gastric cancer. helicobacter mustelae is a closely related bacterium with similar biochemical and morphologic characteristics. h. mustelae infection of antral and fundic mucosa in adult ferrets causes chronic gastritis. an essential virulence property of both helicobacter species is bacterial adhesion to mucosal surfaces. the aim of this study was to determine whet ...19938500901
helicobacter infections in laboratory animals: a model for gastric neoplasias?evidence is rapidly accumulating that helicobacter pylori is a major risk factor for human gastric adenocarcinomas and all low-grade b-cell gastric lymphomas. given this, there is a need to develop animal models with a view to discovering not only how carcinogenesis is initiated, but also how the process can be prevented. the lack of h. pylori animal models suitable for long-term studies means that alternatives are needed. the most productive models are likely to be the helicobacter mustelae-inf ...19958541035
cloning and genetic characterization of the helicobacter pylori and helicobacter mustelae flab flagellin genes and construction of h. pylori flaa- and flab-negative mutants by electroporation-mediated allelic exchange.helicobacter pylori is one of the most common human pathogens. it causes chronic gastritis and is involved in the pathogenesis of gastroduodenal ulcer disease and possibly gastric carcinoma. helicobacter mustelae is a bacterium closely related to h. pylori that causes gastritis and ulcer disease in ferrets and is therefore considered an important animal model of gastric helicobacter infections. motility, even in a viscous environment, is conferred to the bacteria by several sheathed flagella and ...19938501031
mnng-induced gastric carcinoma in ferrets infected with helicobacter mustelae.n-methyl-n-nitro-n'-nitrosoguanidine (mnng) is a gastric carcinogen in several animal species and has been used in a number of systems to dissect the co-carcinogenic potential of various compounds in the induction of gastric adenocarcinoma. recent epidemiological evidence suggests that helicobacter pylori may play a role as a co-carcinogen in the etiology of this tumor in humans and we have been interested in developing an animal model to study this possibility. a related organism, h. mustelae, ...19938403224
identification and molecular characterization of a major ring-forming surface protein from the gastric pathogen helicobacter mustelae.the spiral microaerophilic bacterium helicobacter mustelae is linked to gastritis and gastric ulcers in ferrets. electron microscopy of h. mustelae showed the presence of a laterally extensive array of 8.5-nm-diameter rings on the cell surface, which was shown to be composed of a 150kda protein. this protein was purified, and the sequence of 10 amino-terminal residues was determined. polyclonal antibody against the purified 150 kda protein labelled the ring structures on the homologous strain by ...19948170397
helicobacter mustelae-associated hypergastrinemia in ferrets (mustela putorius furo).to determine whether ferrets naturally infected with helicobacter mustelae were hypergastrinemic, compared with ferrets that were specific-pathogen-free (spf) for h mustelae.19968633798
development of a 14c-urea breath test in ferrets colonised with helicobacter mustelae: effects of treatment with bismuth, antibiotics, and urease inhibitors.a 14c-urea breath test analogous to its clinical counterpart is described for use in ferrets naturally or experimentally infected with helicobacter mustelae. the test is performed within a sealed glass metabolism chamber through which air is drawn at a constant rate and expired breath collected into sodium hydroxide. peak 14co2 production occurred approximately 1 hour after substrate administration. both inter- and intra-animal responses were highly reproducible, with mean coefficients of variat ...19938432469
genome conservation in helicobacter mustelae as determined by pulsed-field gel electrophoresis.genomic dna from 15 strains of helicobacter mustelae was subjected to pulsed-field gel electrophoresis (pfge) after digestion with paci and sfii. h. mustelae genome dna appeared very similar in all strains examined, whether isolated from ferrets or mink or from animals bred in either the usa or in the uk. the h. mustelae genome size was estimated to be 1.7 mb, similar in size to that of h. pylori. a minor difference in paci pfge pattern and genome size was observed between rifampicin-resistant a ...19948013879
protein hpn: cloning and characterization of a histidine-rich metal-binding polypeptide in helicobacter pylori and helicobacter mustelae.helicobacter pylori is a human gastrointestinal pathogen involved in gastritis, duodenal ulcers, and gastric neoplasia. this microorganism produces large amounts of a urease which, like all known ureases, has nickel in the active site. we have identified a protein in clinical isolates of h. pylori and an identical protein in the ferret pathogen helicobacter mustelae that strongly binds ni2+ and zn2+. this protein has been named hpn to emphasize its origins in h. pylori and its affinity for nicke ...19957790085
comparison of helicobacter mustelae and helicobacter pylori adhesion to eukaryotic cells in vitro.bacterial adhesion to mucosal surfaces is an important pathogenic mechanism for helicobacter-induced gastritis. the aims of this study were to compare binding of selected helicobacter mustelae and helicobacter pylori strains to lipids extracted from hep-2, chinese hamster ovary, human embryonic lung cells, and ferret gastrointestinal tissues as well as to intact tissue culture cells and to analyze the fatty acids of the receptor.19957657097
effect of helicobacter mustelae infection on ferret gastric epithelial cell proliferation.the effect of helicobacter mustelae infection on gastric epithelial proliferation was studied in ferrets colonized with h.mustelae and specific pathogen-free (spf) ferrets not infected with h.mustelae. thirteen h. mustelae-infected ferrets between the ages of 13 and 32 months and 16 spf ferrets between 6 and 18 months were analyzed. bacterial cultures, urease tests and warthin-starry stains were used to identify h.mustelae. tissues obtained from the antrum and the body regions of the stomach wer ...19957634423
gastric disease in ferrets: effects of helicobacter mustelae, nitrosamines and reconstructive gastric surgery.animal models are being used to study the mechanisms by which helicobacter spp. induce gastric disease. to assess the effects of a natural gastric pathogen, helicobacter mustelae, in the development of chronic gastritis, premalignancy and cancer, the ferret model was studied under natural and experimental conditions.19947735938
long-term supplementation of canthaxanthin does not inhibit gastric epithelial cell proliferation in helicobacter mustelae-infected ferrets.the effect of canthaxanthin (cx), a nonprovitamin a carotenoid, on gastric epithelial proliferation was studied in ferrets colonized with helicobacter mustelae, which causes a chronic gastritis and an increased gastric epithelial cell proliferation. seven spayed female ferrets were dosed by gavage with cx beadlets (50 mg/kg body wt, 5 d/wk) over 2 y, whereas seven control animals were given placebo beadlets. at the end of the 2-y-period, ferrets were killed, and gastric tissues were obtained fro ...19957562083
microbiological aspects of helicobacter pylori (campylobacter pylori).the human gastric pathogen campylobacter pylori has recently been reclassified as helicobacter pylori, and a related spiral bacterium found in the stomach of ferrets has been designated helicobacter mustelae. the general microbiological features of helicobacter pylori are delineated here, with details of phenotypic differences between helicobacter pylori and helicobacter mustelae; comparisons are made with wolinella succinogenes and campylobacter jejuni. the helicobacter organisms possess an ext ...19902406141
gastric colonization by campylobacter pylori subsp. mustelae in ferrets.campylobacter pylori subsp. mustelae was cultured from both normal and inflamed gastric mucosa of ferrets. examination of neonatal, juvenile, and adult ferrets established that the gastric mucosa in the majority of preweanling (age, less than 6 weeks) ferrets sampled were not colonized with c. pylori subsp. mustelae, whereas the gastric mucosa of 100% of adult ferrets were colonized with this gastric organism. c. pylori subsp. mustelae was isolated from the gastric mucosa on a sequential basis f ...19883169994
eradication of helicobacter mustelae from the ferret stomach: an animal model of helicobacter (campylobacter) pylori chemotherapy.colonization of the ferret stomach by helicobacter mustelae has been suggested as a possible animal model for helicobacter pylori-associated gastroduodenal disease of humans. our study was designed to determine whether antimicrobial chemotherapy could eradicate h. mustelae from ferrets. triple antimicrobial therapy combining amoxicillin, metronidazole, and bismuth subsalicylate was successful in eradicating the organism from 5 of 7 (71%) adult ferrets. despite apparent in vitro susceptibility, n ...19902393285
ranitidine bismuth citrate and clarithromycin, alone or in combination, for eradication of helicobacter mustelae infection in determine whether ranitidine bismuth citrate, clarithromycin, or a combination of ranitidine bismuth citrate and clarithromycin would be efficacious in eradication of helicobacter mustelae infection in ferrets.199910791942
helicobacter mustelae-associated gastritis in ferrets. an animal model of helicobacter pylori gastritis in humans.gastric helicobacter mustelae was present in 100% of 11 adult female ferrets (mustela putorius furo). the high immunoglobulin g antibody levels to h. mustelae in all ferrets showed a significant immune response to the organism. urease mapping of the ferret stomach indicated that the bacteria heavily colonized the proximal duodenum and antrum and, to a lesser extent, the corpus. the histological gastritis observed coincided with presence of h. mustelae. superficial gastritis was noted in the oxyn ...19902365188
purification and characterization of helicobacter mustelae urease.helicobacter mustelae is a urease-rich bacterium associated with gastritis in ferrets. the ureases of h. mustelae and helicobacter pylori, a bacterium implicated in human gastritis, share many characteristics. helicobacter sp. ureases appear to be unique among bacterial enzymes in exhibiting submillimolar km values and in being composed of two subunits.19911879950
helicobacter mustelae-induced gastritis and elevated gastric ph in the ferret (mustela putorius furo).helicobacter mustelae has been cultured from the stomachs of ferrets with chronic gastritis; the lesions in the stomach have many of the same histological features seen in h. pylori gastritis in humans. to determine whether h. mustelae-negative ferrets with normal gastric mucosa were susceptible to colonization and whether gastritis developed after infection, four h. mustelae-negative ferrets treated with cimetidine were inoculated orally on two successive days with 3 ml (1.5 x 10(8) cfu) of h. ...19912037349
helicobacter mustelae isolation from feces of ferrets: evidence to support fecal-oral transmission of a gastric helicobacter.helicobacter mustelae has been isolated from stomachs of ferrets with chronic gastritis and ulcers. when h. mustelae is inoculated orally into h. mustelae-negative ferrets, the animals become colonized and develop gastritis, a significant immune response, and a transient hypochlorhydria. all of these features mimic helicobacter pylori-induced gastric disease in humans. because the epidemiology of h. pylori infection is poorly understood and its route of transmission is unknown, the feces of wean ...19921370432
an ultrastructural study of helicobacter mustelae and evidence of a specific association with gastric mucosa.the ultrastructure of helicobacter mustelae, a natural inhabitant of the ferret stomach, has been studied and compared with the human gastroduodenal pathogen h. pylori. h. mustelae is a short, slightly curved rod, 2 microns x 0.5 micron, with four or more sheathed flagella. the most common flagellar configuration is a single flagellum at one terminus, bipolar arrangement at the other end and a lateral flagellum. dense inclusion bodies were observed below the flagellar insertion sites. it is sugg ...19921613782
pyloric adenocarcinoma in a ferret.pyloric adenocarcinoma was diagnosed in a ferret with clinical signs of gastric distention. the development of this tumor may be related to helicobacter mustelae infection in the gastric mucosa of ferrets. pyloric adenocarcinoma has only recently been reported in ferrets and should be considered as a differential diagnosis for gastric distention in this species.19921607319
gastric colonization of the ferret with helicobacter species: natural and experimental infections.helicobacter mustelae, isolated from the stomachs of adult ferrets, appears to have a world-wide distribution. ferrets are colonized with h. mustelae at a young age, usually 5-6 weeks; in our experience 100% of adult ferrets are colonized in both the antrum and the fundus. gastric infection correlates with elevation of serum igg antibodies to h. mustelae. in the oxyntic mucosa the presence of superficial gastritis coincides closely with the presence of h. mustelae. in the distal antrum the organ ...19911833810
gastric bacteria other than helicobacter pylori.since the culture of helicobacter pylori from the human stomach in 1983 there has been renewed interest in other bacteria that had been observed in animal stomachs as early as late in the nineteenth century. many of these bacteria have now been isolated and have been shown to belong to the same genus, helicobacter, which currently contains nine species. study of the gastric helicobacters is important because it provides relevant information about how bacteria can survive in the gastric environme ...19938449568
surface properties of helicobacter mustelae and ferret gastrointestinal mucosa.helicobacter mustelae is a gastric pathogen in ferrets that adheres to epithelial cells both in vitro and in vivo. in this study, the authors examine the role of surface hydrophobic properties in the adhesion of these organisms to eukaryotic cell surfaces. the surface properties of six h. mustelae strains were characterized by hydrophobic interaction chromatography (hic), salt aggregation testing (sat) and contact-angle measurement by axisymmetric drop-shape analysis (adsa). contact angles in mu ...19968697675
animal models and vaccine development.following the demonstration of helicobacter pylori as a major gastroduodenal pathogen there was a need to develop animal models in order to investigate mechanisms of pathogenesis and to be able to test new treatment strategies. helicobacter pylori will only colonize a limited number of hosts including non-human primates, germ-free or barrier raised piglets, germ-free dogs and recently laboratory raised cats. although these models have proved useful there is a need for more convenient small anima ...19958563056
ex-vivo treatment of gastric helicobacter infection by photodynamic therapy.attempts to develop pdt for eradication of helicobacter infection have only been successful in vitro. we have investigated the effect of topical sensitization (except ala) of helicobacter mustelae on explanted ferret gastric mucosa using one of five sensitizers (methylene blue (mb), toluidine blue o (tbo), phthalocyanine, haematoporphyrin derivative and 5-aminolavulinic acid), followed by irradiation with an appropriately tuned copper vapour pumped dye laser. a 90% reduction in counts of bacteri ...19968725054
therapeutic immunization against helicobacter mustelae in naturally infected ferrets.helicobacter infection of the gastric antrum is responsible for a number of gastric disorders. antibiotic therapy is lengthy and is not always effective. it has been shown previously that oral immunization against helicobacter felis in mice can prevent colonization after challenge. the aim of this study was to investigate the efficacy of therapeutic immunization in eradicating an established helicobacter infection and in reducing gastritis.19968964402
comparative ultrastructural and functional studies of helicobacter pylori and helicobacter mustelae flagellin mutants: both flagellin subunits, flaa and flab, are necessary for full motility in helicobacter species.helicobacter mustelae causes chronic gastritis and ulcer disease in ferrets. it is therefore considered an important animal model of human helicobacter pylori infection. high motility even in a viscous environment is one of the common virulence determinants of helicobacter species. their sheathed flagella contain a complex filament that is composed of two distinctly different flagellin subunits, flaa and flab, that are coexpressed in different amounts. here, we report the cloning and sequence de ...19957768796
random mutagenesis to identify novel helicobacter mustelae virulence factors.helicobacter mustelae is a gastric pathogen of ferrets, where it causes disorders similar to those caused by helicobacter pylori in humans. the h. mustelae ferret model therefore has potential for the in vivo study of helicobacter pathogenesis in general. in this study a library of 500 individual h. mustelae mutants was generated using an in vitro random insertion mutagenesis technique. mutants were subsequently tested for motility and adherence, and 43 of the 500 mutants tested were found to be ...200717316371
role of gastric ph in isolation of helicobacter mustelae from the feces of ferrets.helicobacter mustelae colonizes the gastric mucosa of ferrets and causes persistent chronic gastritis.19938380398
adherence of helicobacter pylori.helicobacter pylori infects only gastric type epithelium, to which it adheres closely and forms attaching-effacing lesions. similar lesions are also seen in ferrets infected with helicobacter mustelae, the only other host in which peptic ulcer occurs during the course of infection. these observations imply a specific interaction between bacterial adhesin(s) and host receptor(s). they account for the adherence of h. pylori to the gastric epithelium and suggest that adherence is an important virul ...19968730255
characterization of nikr-responsive promoters of urease and metal transport genes of helicobacter mustelae.the nikr protein is a nickel-responsive regulator, which in the gastric pathogen helicobacter pylori controls expression of nickel-transporters and the nickel-cofactored urease acid resistance determinant. although nikr-dna interaction has been well studied, the helicobacter nikr operator site remains poorly defined. in this study we have identified the nikr operators in the promoters of two inversely nickel-regulated urease operons (ureab and urea2b2) in the ferret pathogen helicobacter mustela ...201019894125
infection of the ferret stomach by isogenic flagellar mutant strains of helicobacter mustelae.helicobacter mustelae, like helicobacter pylori, possesses two flagellin proteins, flaa and flab. isogenic mutant strains of h. mustelae have been constructed by disruption of the flaa or flab gene with a kanamycin resistance cassette or by introduction of both a kanamycin and a chloramphenicol resistance gene to produce a double mutant. to determine whether one or both flagellin proteins are necessary for colonization and persistence of infection with h. mustelae, 19 ferrets, specific pathogen ...19979125590
helicobacter mustelae-associated gastric adenocarcinoma in ferrets (mustela putorius furo).helicobacter pylori in humans is associated with active, chronic gastritis, peptic ulcer disease, and most recently has been linked epidemiologically to gastric adenocarcinoma. a related organism, helicobacter mustelae, naturally infects ferrets and also causes a persistent gastritis, a precancerous lesion, and focal glandular atrophy of the proximal antrum. in this report, we document the clinical presentation and histopathologic confirmation of h. mustelae-associated gastric adenocarcinoma in ...19979163879
characterization and therapy for experimental infection by helicobacter mustelae in ferrets.numerous clinical trials evaluating the efficacy of various antimicrobial compounds against helicobacter pylori infection have been performed in humans. a convenient animal model for helicobacter infection would facilitate the evaluation of novel therapies. these experiments were performed to evaluate the use of ferrets as a model of helicobacter infection.19969398912
natural and experimental helicobacter mustelae reinfection following successful antimicrobial eradication in ferrets.recrudescence or reinfection may occur after eradication of helicobacter pylori in humans.19969398911
nonprimate animal models of h. pylori infection.ever since the realization that helicobacter pylori was intimately associated with the development of gastritis and peptic ulcer disease in humans, there has been a need for a simple animal model in which modes of pathogenicity, transmission, immunization, and chemotherapeutic intervention can be evaluated. whereas small animals such as mice and rats are particularly well suited as experimental hosts for many infections, early studies suggested that h. pylori had a very narrow host range that di ...199721351037
promotion of ulcerative duodenitis in young ferrets by oral immunization with helicobacter mustelae and muramyl dipeptide.the purpose of this study was to determine whether oral immunization of ferret kits with a whole-cell sonicate of helicobacter mustelae lysate (hml) and the adjuvant muramyl dipeptide (mdp) would reduce the incidence of natural colonization with h. mustelae and the extent of helicobacter-associated gastritis by enhancing the host mucosal immune response.19979432331
inhibition of helicobacter pylori and helicobacter mustelae binding to lipid receptors by bovine colostrum.helicobacter pylori, the etiologic agent of chronic-active gastritis and duodenal ulcers in humans, and helicobacter mustelae, a gastric pathogen in ferrets, bind to phosphatidylethanolamine (pe), a constituent of host gastric mucosal cells, and to gangliotetraosylceramide (gg4) and gangliotriaosylceramide (gg3). the effect of a bovine colostrum concentrate (bcc) on the interaction of h. pylori and h. mustelae to their lipid receptors was examined. bcc blocked attachment of both species to gg4, ...19989534968
molecular mimicry of ferret gastric epithelial blood group antigen a by helicobacter mustelae.molecular mimicry of lewis blood group antigens by helicobacter pylori may be involved in immune evasion by the bacteria and in the pathogenesis of chronic atrophic gastritis. helicobacter mustelae infects ferrets naturally, causing gastritis, and may be involved in ulcerogenesis. the aim of this study was to determine if h. mustelae shows a similar form of molecular mimicry.19989516389
adherence of isogenic flagellum-negative mutants of helicobacter pylori and helicobacter mustelae to human and ferret gastric epithelial cells.isogenic flagellum-negative mutants of helicobacter pylori and helicobacter mustelae were screened for their ability to adhere to primary human and ferret gastric epithelial cells, respectively. we also evaluated the adherence of an h. pylori strain with a mutation in the flba gene, a homologue of the flbf/lcrd family of genes known to be involved in the regulation of h. pylori flagellar biosynthesis. h. pylori and h. mustelae mutants deficient in production of flaa or flab and mutants deficient ...200010858255
sequence and antigenic variability of the helicobacter mustelae surface ring protein hsr.we have identified an array of more than 500 repetitive sequences flanking the hsr gene, which encodes the major surface protein of the ferret pathogen helicobacter mustelae. the repeats show identity exclusively to the amino-terminal half of hsr. analysis of hsr from three strains indicated variability of exposed epitopes. characterization of an hsr mutant showed that hsr is not an adhesin.200111292773
helicobacter mustelae lipid a structure differs from that of helicobacter pylori.the lipid a structure of the gram-negative bacterium helicobacter mustelae, a ferret gastric pathogen responsible for the onset of gastric diseases in its host, was investigated. two variant lipid a structures were found in the same strain. one structure contained a bisphosphorylated beta-(1-->6)-linked d-glucosamine backbone disaccharide with hydroxytetradecanoic acid in amide linkages. unlike the structure described for the lipid a of the related human helicobacter pylori gastric pathogen, whi ...200111418100
the ferret gastrointestinal tract and helicobacter mustelae infection. 200515817250
an abc transporter and a tonb ortholog contribute to helicobacter mustelae nickel and cobalt acquisition.the genomes of helicobacter species colonizing the mammalian gastric mucosa (like helicobacter pylori) contain a large number of genes annotated as iron acquisition genes but only few nickel acquisition genes, which contrasts with the central position of nickel in the urease-mediated acid resistance of these gastric pathogens. in this study we have investigated the predicted iron and nickel acquisition systems of the ferret pathogen helicobacter mustelae. the expression of the outer membrane pro ...201020643857
failure of surface ring mutant strains of helicobacter mustelae to persistently infect the ferret stomach.helicobacter mustelae, the gastric pathogen of ferrets, produces an array of surface ring structures which have not been described for any other member of the genus helicobacter, including h. pylori. the unique ring structures are composed of a protein named hsr. to investigate whether the hsr rings are important for colonization of the ferret stomach, ferrets specific pathogen free for h. mustelae were inoculated with an hsr-deficient mutant strain or the wild-type h. mustelae strain. quantitat ...200312704104
molecular identification of helicobacter dna present in human colorectal adenocarcinomas by 16s rdna pcr amplification and pyrosequencing analysis.seroepidemiological studies have indicated that helicobacter pylori infection might be a possible risk factor for colorectal adenocarcinoma (crc) development. however, limited information is available as to whether or not helicobacter species are present in crc tissues. in this study the presence of helicobacter dna in 77 crc biopsies was investigated by means of a helicobacter species-specific 16s rdna pcr assay and real-time dna pyrosequencing of the 16s rdna variable v3 region. pyrosequencing ...200516192433
helicobacter mustelae-associated gastric malt lymphoma in ferrets.gastric lymphoma resembling gastric mucosa-associated lymphoid tissue (malt) lymphoma linked with helicobacter pylori infection in humans was observed in ferrets infected with h. mustelae. four ferrets with ante- or postmortem evidence of primary gastric lymphoma were described. lymphoma was diagnosed in the wall of the lesser curvature of the pyloric antrum, corresponding to the predominant focus of h. mustelae induced gastritis in ferrets. two ferrets had low-grade small-cell lymphoma and two ...19979212752
antigastric autoantibodies in ferrets naturally infected with helicobacter mustelae.infection with helicobacter pylori has been associated with induction of autoantibodies that cross-react with the gastric mucosa. there have been discordant reports as to whether or not these autoantibodies arise due to molecular mimicry between h. pylori and host cell antigens on parietal cells. in this study, we investigated whether molecular mimicry by h. mustelae causes autoantibodies in infected ferrets. serum from h. mustelae-infected ferrets reacted with parietal cells in the ferret gastr ...200111254638
comparative genomics and proteomics of helicobacter mustelae, an ulcerogenic and carcinogenic gastric pathogen.helicobacter mustelae causes gastritis, ulcers and gastric cancer in ferrets and other mustelids. h. mustelae remains the only helicobacter other than h. pylori that causes gastric ulceration and cancer in its natural host. to improve understanding of h. mustelae pathogenesis, and the ulcerogenic and carcinogenic potential of helicobacters in general, we sequenced the h. mustelae genome, and identified 425 expressed proteins in the envelope and cytosolic proteome.201020219135
isolation of helicobacter mustelae from ferrets in new zealand.the bacterial genus helicobacter contains over 20 species, including the human gastric pathogen h. pylori, and the mustelid-specific h. mustelae. a previous study in this country failed to isolate h. mustelae from a captive breeding colony of ferrets. we sought to confirm whether or not h. mustelae was present in this country.200016032121
metal-responsive gene regulation and metal transport in helicobacter species.helicobacter species are among the most successful colonizers of the mammalian gastrointestinal and hepatobiliary tract. colonization is usually lifelong, indicating that helicobacter species have evolved intricate mechanisms of dealing with stresses encountered during colonization of host tissues, like restriction of essential metal ions. the recent availability of genome sequences of the human gastric pathogen helicobacter pylori, the murine enterohepatic pathogen helicobacter hepaticus and th ...200717294126
iron-containing urease in a pathogenic bacterium.helicobacter mustelae, a gastric pathogen of ferrets, synthesizes a distinct iron-dependent urease in addition to its archetypical nickel-containing enzyme. the iron-urease is oxygen-labile, with the inactive protein exhibiting a methemerythrin-like electronic spectrum. significantly, incubation of the oxidized protein with dithionite under anaerobic conditions leads to restoration of activity and bleaching of the spectrum. structural analysis of the oxidized species reveals a dinuclear iron met ...201121788478
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