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PubMed1998

[Helicobacter pylori infection and socioeconomic factors among adult Danes].

The aim of this study was to examine the relationship between housing conditions, educational level, occupational factors, and serologically diagnosed acute and chronic Helicobacter pylori infection. IgG, IgM, and IgA antibodies against Helicobacter pylori were measured by ELISA techniques in sera obtained from a random sample of 3589 Danes participating in a population study. Poor social status (odds ratio 2.2 [1.7-3.0]), short duration of schooling (odds ratio 2.0 [1.3-2.5]), lack of vocational training/education (odds ratio 1.4 [1.2-1.7]), unskilled work (odds ratio 1.7 [1.2-2.5]), and high work-related energy expenditure (odds ratio 1.4 [1.1-1.9]) increased the likelihood of chronic Helicobacter pylori infection. Chronic Helicobacter pylori infection was frequently found in people with a history of living abroad. Increased levels solely of IgM antibodies to H. pylori, interpreted as a sign of acute infection, were found more often in people who were divorced (odds ratio 2.3 [1.2-4.4]) or unmarried (odds ratio 2.0 [1.1-3.8]) and in people who worked long hours (odds ratio 2.0 [1.1-4.0]). In conclusion, educational and occupational factors relate to the likelihood of chronic Helicobacter pylori infection in adults. The rate of acute Helicobacter pylori infection is probably increased in single adults.

Adult↗
PubMed1998

Helicobacter pylori and diminished growth in children: is it simply a marker of deprivation?

Helicobacter pylori is an accepted gastroduodenal pathogen and has recently been investigated for possible implications in non gastroenterological diseases such as growth impairment coronary heart disease and diabetes. Infection by cytotoxic, i.e., CagA or VacA positive strains seems more likely to lead to more serious gastroduodenal diseases compared to infection by non cytotoxic strains, but the possible role of CagA or VacA positive strains in non gastroenterological diseases has not been investigated. Aim of the present study was to evaluate the prevalence of Helicobacter pylori infection as well as CagA and VacA positivity in three paediatric populations auxologically normal, hyposomic and diabetic children. Sera from a total of 522 children (auxologically normal: 246, hyposomic: 164, diabetic: 112) were analyzed by a novel Recombinant ImmunoBlot Assay-Strip Immunoblot Assay--RIBA SIA--which contain individual band for whole Helicobacter pylori lysate and recombinant CagA and VacA. The overall seroprevalence of reactivities against Helicobacter pylori lysate, CagA and VacA were: 7.3%, 9.3%, 6.9% vs 11.6%, 7.9%, 8.5% vs 14.3%, 13.4%, 8% (p = NS) in auxologically normal, hyposomic and diabetic children, respectively. Summarizing, we found a similar prevalence of reactivity against both whole Helicobacter pylori lysate as well as recombinant CagA and VacA between auxologically normal, hyposomic and diabetic children. Our data do not support a possible role of Helicobacter pylori in diminished growth in children.

Adolescent↗
PubMed1995

Development of a rapid PCR method for identification of Helicobacter pylori in dental plaque and gastric biopsy specimens.

A rapid and simple polymerase chain reaction (PCR) method was developed to detect Helicobacter pylori in gastric biopsy specimens and dental plaque samples. The primers were targeted to the 16S rRNA sequence of Helicobacter pylori strain ATCC 43504. The system was found to have a theoretical detection level of 0.5 to 5 Helicobacter pylori cells in a 5 microliters sample of dental plaque. In the absence of plaque, the detection level was even better: theoretically, 0.05 to 0.5 Helicobacter pylori cells were detected in water suspension. However, this appeared to be due to the presence of free bacterial DNA in the culture used for the sensitivity determination. Thus, the actual sensitivity of the system was found to be fewer than five Helicobacter pylori cells, irrespective of the type of sample used. The method was then used to analyse 29 dental plaque and gastric biopsy specimens collected from patients with a history of recurrent peptic ulcer disease. Fourteen stomach specimens were positive for Helicobacter pylori when tested with the PCR method, while the respective figures with culture, histological examination and the urease test were 11, 12 and 9. No positive dental plaque samples were observed.

Adult↗
PubMed1994

Helicobacter pylori potentiates histamine release from rat serosal mast cells induced by bile acids.

In the present study we have experimentally addressed the effects of Helicobacter pylori on the bile acid capability of histamine release. Bile acids alone were confirmed to be able to induce in vitro histamine release from rat serosal and mucosal mast cells. On the contrary, no significant histamine release was obtained when incubating any Helicobacter pylori preparations alone with mast cells. However, histamine release induced by bile acids was significantly enhanced, without any significant increase in lactate dehydrogenase activity, when whole washed or formalin-killed bacterial cells or crude cell walls were incubated with mast cells in the presence of cholic (0.3 mM), deoxycholic (0.3 mM), or lithocholic (0.3 mM) acids, chenodeoxycholylglycine (0.3 mM), and deoxycholyltaurine (3 mM). The electron microscopic features of mast cells incubated with Helicobacter pylori were consistent with an exocytotic secretion. The release of histamine induced by 0.3 mM deoxycholic acid in the presence of Helicobacter pylori was inhibited by the preincubation of the cells with dimaprit (an H2 agonist) and potentiated by the H2 antagonist, ranitidine. The current results suggest a link between human Helicobacter pylori infection and histamine release and a possible involvement of gastric mucosal mast cells in the pathogenesis of Helicobacter pylori-associated gastritis.

Animals↗
PubMed2005

Helicobacter genus DNA fragments are commonly detectable in bile from patients with extrahepatic biliary diseases and associated with their pathogenesis.

Several Helicobacter species are known to colonize the biliary tract in animals and have been identified in the gallbladder bile of a high proportion of Chilean patients with gallbladder cancer. In this study, we tried to examine the presence of Helicobacter species in the bile to know their participation in the development of extrahepatic biliary diseases. DNA was extracted from 57 bile samples from 30 patients with benign biliary diseases (cholecystolithiasis and choledochocystolithiasis), 6 malignant biliary diseases (gallbladder cancer and common bile duct cancer), and 21 nonbiliary diseases. The presence of Helicobacter genus-, H. pylori-, H. hepaticus-, and H. bilis-specific 16S rRNA genes, the H. pylori urease A gene, and the H. pylori 26K protein gene in the bile was determined by PCR and sequencing analysis. Helicobacter genus DNA (shorter amplicons, 400 bp) was statistically frequently detected in biles from 53% (16/30) and 86% (5/6) of benign and malignant biliary diseases, compared with 9% (2/21) of nonbiliary diseases, but longer amplicons (1200 bp) were not detectable in any samples. The H. pylori urease A gene (nested amplicon) was also frequently found in bile, whether benign, malignant, or control, though neither H. pylori 16S rRNA nor the 26K protein gene was detectable in any bile samples. H. bilis-16S rRNA genes were detectable in only two cases. H. hepaticus was not detectable in any samples. DNA fragments of Helicobacter species other than H. pylori, H. hepaticus, and H. bilis are commonly detectable in the bile of patients with extrahepatic biliary diseases, whether benign or malignant, implying that the Helicobacter genus may be directly or indirectly involved in the pathogenesis of these diseases.

Bile↗
PubMed2005

Antibacterial activity of Tabebuia impetiginosa Martius ex DC (Taheebo) against Helicobacter pylori.

The growth-inhibiting activity of Tabebuia impetiginosa Martius ex DC dried inner bark-derived constituents against Helicobacter pylori ATCC 43504 was examined using paper disc diffusion and minimum inhibitory concentration (MIC) bioassays. The activity of the isolated compounds was compared to that of the commercially available anti-Helicobacter pylori agents, amoxicillin, metronidazole, and tetracycline. The biologically active components of Tabebuia impetiginosa dried inner bark (taheebo) were characterized by spectroscopic analysis as 2-(hydroxymethyl)anthraquinone, anthraquinone-2-carboxylic acid, and 2-hydroxy-3-(3-methyl-2-butenyl)-1,4-naphthoquinone (lapachol). With the paper disc diffusion assay 2-(hydroxymethyl)anthraquinone exhibited strong activity against Helicobacter pylori ATCC 43504 at 0.01 mg/disc. Anthraquinone-2-carboxylic acid, lapachol and metronidazole were less effective, exhibiting moderate anti-Helicobacter pylori activity at 0.1 mg/disc. Amoxicillin and tetracycline were the most potent compounds tested, displaying very strong activity at 0.005 mg/disc. 2-(Hydroxymethyl)anthraquinone exhibited moderate activity at this dose. Tetracycline still had strong activity at 0.001 mg/disc while amoxicillin had little activity at this dose. In the MIC bioassay, 2-(hydroxymethyl)anthraquinone (2 microg/mL), anthraquinone-2-carboxylic acid (8 microg/mL), and lapachol (4 microg/mL) were more active than metronidazole (32 microg/mL) but less effective than amoxicillin (0.063 microg/mL) and tetracycline (0.5 microg/mL). The anti-Helicobacter pylori activity of seven 1,4-naphthoquinone derivatives (structurally related to lapachol), 1,4-naphthoquinone, 5,8-dihydroxy-1,4-naphthoquinone (naphthazarin), 2-methyl-1,4-naphthoquinone (menadione), 2-hydroxy-1,4-naphthoquinone (lawsone), 5-hydroxy-2-methyl-1,4-naphthoquinone (plumbagin), 5-hydroxy-1,4-naphthoquinone (juglone), and 2,3-dichloro-1,4-naphthoquinone (dichlone) was also evaluated using the paper disc assay. Menadione and plumbagin were the most potent compounds tested with the later still exhibiting very strong activity at 0.001 mg/disc. Menadione, juglone and tetracycline had strong activity at this low dose while the latter two compounds and amoxicillin had very strong activity at 0.005 mg/disc. Lawsone was unusual in that it had very strong activity at 0.1 and 0.05 mg/disc but weak activity at doses of 0.01 mg/disc and lower. Naphthazalin, lapachol and dichlone had similar activities while metronidazole had the lowest activity of all compounds tested. These results may be an indication of at least one of the pharmacological actions of taheebo. The Tabebuia impetiginosa dried inner bark-derived materials, particularly 2-(hydroxymethyl)anthraquinone, merit further study as potential Helicobacter pylori eradicating agents or lead compounds.

Anti-Bacterial Agents↗
PubMed2002

Helicobacter infection in patients with HCV-related chronic hepatitis, cirrhosis, and hepatocellular carcinoma.

Chronic hepatitis may progress to cirrhosis and hepatocellular carcinoma (HCC). HCC represents one of the most common human cancers. Incidence rates for this tumor vary widely on a worldwide, suggesting that environmental factors such as infectious microorganisms, carcinogens, or nutrition play a role in its pathogenesis. Several Helicobacter spp. colonize the liver of animals and induce hepatitis. The aim of this study was to determine whether Helicobacter infection was associated with HCV-related liver diseases in humans. Liver tissue samples, including biopsy and surgically excised tissues, were collected from patients positive for hepatitis C viruses (HCV) RNA in the serum. Genomic DNA was extracted from sections of formalin-fixed paraffin-embedded tissues by using the QIAamp Tissue Kit and subjected to polymerase chain reaction (PCR) analysis using two sets of Helicobacter-specific 16S ribosomal RNA primers. To identify positive samples for H. pylori, a set of primers specific for a conserved region in the H. pylori vacA gene were also used. The patients' H. pylori status was determined by ELISA. Forty-one patients (mean age 54.9, range 19-78 years; 24 men) were studied. Thirty patients had chronic viral hepatitis (CH) without (N = 18) or with (N = 12) cirrhosis (CIR), and 11 patients had HCC. Anti-H. pylori IgG was detected in 54%. The expected 422- and 210-bp fragments of Helicobacter 16S rRNA were amplified from 27% of liver samples, including 17% of CH-CIR and 55% of HCC (P = 0.004). The vacA sequence was amplified in 10 of 41(24%) samples (27% of those with HCC). These data confirm the presence of H. pylori DNA sequences in human liver and suggest an association of Helicobacter spp. with HCV-related chronic liver diseases. Further studies are needed to ascertain whether Helicobacter spp. infection plays a role in the development of HCC.

Adult↗
PubMed2005

First report on the occurrence of 'Helicobacter heilmannii' in the stomach of rabbits.

Gastric Helicobacter spp. have been described in a wide range of animal species, including dogs, cats, primates, swine, cattle and rodents. However, in lagomorphs--more specifically rabbits--gastric Helicobacter infections have never been reported. Biopsy specimens were collected from different stomach regions of 23 rabbits, including 10 pet rabbits, 10 industrial animals and 3 research animals. These were subjected to a PCR assay for the detection of Helicobacter DNA. Identification up to the species level was based on 16S rRNA sequence analysis and a recently developed multiplex PCR. Seven rabbits (four pet, one research animal and two industrial animals) tested positive in the Helicobacter genus-specific PCR in the stomach, with the corpus being predominantly positive. H. felis and H. salomonis, hitherto presumed to be naturally hosted by cats and dogs, were detected in three animals and one animal, respectively. One of these animals had been completely devoid of any form of contact with cats or dogs. A H. pullorum/H. rappini-like organism (96% 16S rDNA sequence similarity) was found in an industrially held rabbit. The helicobacters of the two remaining rabbits could not be identified up to the species level. To conclude, this is the first report on the occurrence of Helicobacter spp. in the stomach of rabbits. In view of the fact that H. felis and H. salomonis are put forward as having zoonotic potential, further research is necessary to investigate the implications of these findings not only for the rabbit but also for human health.

Animals↗
PubMed2002

Cloning and characterization of a Helicobacter bizzozeronii urease gene cluster.

The urease gene cluster from Helicobacter bizzozeronii was cloned and sequenced. A genomic library was constructed in a lambda-ZAPII vector using TSP5091-digested H. bizzozeronii chromosomal DNA. Four overlapping recombinant bacteriophages carrying the H. bizzozeronii urease genes were identified by using a fragment of H. bizzozeronii ureB as a probe. Sequence analysis of two clones (pHB1 and pHB3) revealed seven open reading frames encoding proteins with predicted masses of 26.5, 60.3, 21.7, 19.5, 28.6, 21.7 and 29.6 kDa representing the structural genes, Urease A and B and its accessory genes, urease I, E, F, G and H, respectively. In addition, three open reading frames upstream of the ureA gene encoding a putative tRNA transferase, a putative Glucose inhibited division protein B (GidB) and a protein with unknown function were also identified. A clone (pHB5) containing a complete urease gene cluster was constructed. The homologue analysis revealed that UreA polypeptide exhibited 64-90% identity to that of Helicobacter heilmanii, Helicobacter felis, Helicobacter pylori, Helicobacter mustelae and Helicobacter hepaticus. UreB polypeptides exhibited 76.8-96% identity to that of H. heilmanii, H. felis, H. pylori, H. mustelae and H. hepaticus. The UreI, E, F, G and H also showed 44-86% identity to that of H. pylori. Among these accessory genes, UreE had a lowest percentage identity to that of H. pylori.

Amino Acid Sequence↗
PubMed2000

'Flexispira rappini' strains represent at least 10 Helicobacter taxa.

'Flexispira rappini' is a provisional name given to gram-negative, microaerophilic, motile, spindle-shaped micro-organisms with spiral periplasmic fibres and bipolar tufts of sheathed flagella. Several investigators, including Kirkbride, Romero, and Archer isolated strains possessing this morphology. Previously, the phylogenetic position of three 'Flexispira rappini' strains was determined by 165 rRNA sequencing, which indicated that flexispira were members of the genus Helicobacter. As more organisms with 'F. rappini' morphology were isolated, it became apparent that there were multiple Helicobacter taxa with this distinctive morphology. The purpose of this study was to examine a collection of 36 'F. rappini' strains from diverse habitats by using 165 rRNA sequence analysis. The strains fell into 10 taxa, each possibly representing a novel Helicobacter species. Two of these flexispira taxa were previously named, by us, Helicobacter bilis and Helicobacter trogontum. Currently, none of the flexispira taxa contains enough phenotypically and genotypically characterized strains to be formally named 'Helicobacter rappinii'.

Animals↗
PubMed2000

Identification of cdtB homologues and cytolethal distending toxin activity in enterohepatic Helicobacter spp.

A bacterial toxin that causes progressive distension and death of Chinese hamster ovary (CHO) cells and HeLa cells, termed cytolethal distending toxin (Cdt), has been identified in several diarrhoeagenic bacteria, including Campylobacter spp. (C. jejuni and Cq coli), some pathogenic strains of Escherichia coli and Shigella spp. Genes encoding this toxin were identified as a cluster of three adjacent genes cdtA, cdtB and cdtC. Homologues of cdtB from five species of enterohepatic helicobacters (Helicobacter hepaticus, H. bilis, H. canis and two novel Helicobacter spp. isolated from mice and woodchuck, respectively) were identified by means of degenerative PCR primers, cloned and sequenced. The similarities of these partial cdtB nucleotide sequences from these Helicobacter spp. to those of cdtB genes known to be present in other bacteria were: C. jejuni, 58.3-64.8%; E. coli, 52.3-57.8%, Haemophilus ducreyi, 53.4-58.4% and Actinobacillus actinomycetemcomitans, 52.7-58.1%. Bacterial lysates from four of these helicobacters caused characteristic cytolethal distension of HeLa cells. Cdt caused cell cycle arrest at G2/M phase as measured by flow cytometry. The results demonstrated the presence of a toxin in these Helicobacter spp. belonging to the family of Cdt.

Amino Acid Sequence↗
PubMed1993

Helicobacter canis sp. nov., a new species from dogs: an integrated study of phenotype and genotype.

A group of Campylobacter-like organisms (CLOs) were isolated from the faeces of diarrhoeic or healthy dogs, constituting 4% of all CLOs from this source. Since they formed a unique DNA homology group within the genus Helicobacter, and exhibited distinctive phenotypic properties, they were collectively termed the HC group. A polyphasic taxonomic analysis was made of this group. The phenotype of four dog isolates and a single human isolate was unique and could be distinguished bacteriologically from other helicobacters. Electron microscopic ultrastructure revealed defining characteristics of Helicobacter. The 16S rRNA gene of the nominated type strain NCTC 12739T was sequenced, and its analysis delineated the group as a new species of Helicobacter. This conclusion was supported by relative DNA homology and whole-cell protein electrophoretic patterns. We therefore propose the name Helicobacter canis sp. nov. for this group. The species most closely related to H. canis sp. nov. were H. cinaedi, 'Flexispira rappini' and H. fennelliae. A species-specific recombinant DNA probe was cloned from NCTC 12739T for use in routine laboratory identification and epidemiological studies. The faecal source, bile tolerance and lack of urease activity of H. canis sp. nov. suggest that this new Helicobacter species colonizes the lower bowel rather than the stomach.

Animals↗
PubMed2004

Detection of Helicobacter pylori by PCR but not culture in water and biofilm samples from drinking water distribution systems in England.

AIMS: To investigate treated water distribution systems in England as a source of Helicobacter pylori. METHODS AND RESULTS: Water and biofilms were obtained from 11 domestic and seven educational properties and from hydrants, reservoirs and water meters supplied by three water utilities. Samples were cultured on nonselective and antibiotic containing media combined with immunomagnetic separation concentration. Viable helicobacters were not detected in any of the 151 samples but Helicobacter-specific PCR assays detected DNA in 26% of samples from domestic properties, schools and hydrants with the highest frequency in biofilms (42%). Direct sequencing of six selected amplicons confirmed >95% sequence homology to H. pylori. CONCLUSIONS: While viable helicobacters were not isolated, evidence was obtained for the presence of Helicobacter DNA, including that of H. pylori. Biofilms on surfaces within water distribution systems may act either as sites for the passive accumulation of helicobacters or as potentially important reservoirs of infection. SIGNIFICANCE AND IMPACT OF THE STUDY: Our findings strengthen evidence that H. pylori may be transmitted through drinking water. However, there is currently no evidence that viable cells can survive the disinfection levels used in UK mains supplies and the health risk from this source remains unclear.

Base Sequence↗
PubMed2002

Production and application of new monoclonal antibodies specific for a fecal Helicobacter pylori antigen.

The aim of the present study was to establish monoclonal antibodies that could be used to produce a diagnostic test composed of one kind of monoclonal antibody recognizing a fecal Helicobacter pylori antigen. The need to develop such a test arose from disadvantages of the diagnostic test that uses a polyclonal antibody or plural kinds of monoclonal antibodies, such as the lower specificity for H. pylori antigen and the difficulty of reproduction with consistent quality. Mice were immunized with sonicated cells of the coccoid form of H. pylori, and fecal samples from H. pylori-positive subjects were screened by a direct sandwich enzyme immunoassay (EIA) for antibody production from 32 hybridoma clones. The three stable clones produced antibodies (21G2, 41A5, and 82B9) that reacted with the same soluble antigen. Gel filtration chromatography showed that the molecular masses of the cellular antigen and the fecal antigen were the same, 260 kDa. The antigen was labile in response to sodium dodecyl sulfate and heat treatments. A single-step direct sandwich EIA using a single monoclonal antibody, 21G2, was developed. The EIA could detect the antigen in 41 H. pylori clinical isolates and in fecal samples from seven H. pylori-positive subjects. Several kinds of Helicobacter species (Helicobacter felis, Helicobacter hepaticus, Helicobacter mustelae, and Helicobacter cinaedi) except H. pylori, major bacteria in feces (Campylobacter jejuni, Bacteroides vulgatus, Bifidobacterium breve, Bifidobacterium infantis, and Escherichia coli), and fecal samples from six H. pylori-negative subjects showed negative results. These results indicate that the new monoclonal antibodies and the new specific EIA would be useful as a noninvasive method of diagnosis of H. pylori infection.

Animals↗
PubMed1996

Role of the host in pathogenesis of Helicobacter-associated gastritis: H. felis infection of inbred and congenic mouse strains.

In humans, Helicobacter pylori establishes a chronic infection which can result in various degrees of gastric inflammation, peptic ulcer disease, and a predisposition to gastric cancer. It has been suggested that bacterial virulence factors such as the vacuolating toxin (VacA) and the cytotoxin-associated gene product (CagA) may play a major role in determining the clinical outcome of Helicobacter infections. The role of host responses in these varied outcomes has received little attention. Helicobacter felis, which does not express CagA or VacA, causes chronic infection and inflammation in a well-characterized mouse model. We have used this model to evaluate the role of host responses in Helicobacter infections. BALB/c, C3H, and C57BL/6 mice were orally infected with a single strain of H. felis, and 2 and 11 weeks after infection, the mice were sacrificed and evaluated histologically for magnitude of H. felis infection. Intensity and extent of inflammation, and cellular composition of the inflammatory infiltrate. All three strains of mice demonstrated comparable levels of infection at 11 weeks, but the pattern and intensity of inflammation varied from minimal in BALB/c mice to severe in C57BL/6 mice. Gastric epithelial erosions were noted in C3H mice, and mucous cell hyperplasia was observed in C3H and C57BL/6 mice. Abundant mucosal mast cells were observed in the gastric tissues of all three mouse strains. Studies using major histocompatibility complex (MHC)-congenic mice revealed probable contributions by both MHC and non-MHC genes to Helicobacter-induced inflammation. Thus, large variations in the severity of disease were observed after infection of different inbred strains and congenic mice with a single isolate of H. felis. These results demonstrate the importance of the host response in disease outcome following gastric Helicobacter infection.

Animals↗
PubMed2000

Expression of the Helicobacter pylori ureI gene is required for acidic pH activation of cytoplasmic urease.

ureI encodes an integral cytoplasmic membrane protein. It is present in the urease gene cluster of Helicobacter pylori and is essential for infection and acid survival, but its role is unknown. To determine the function of UreI protein, we produced H. pylori ureI deletion mutants and measured the pH dependence of urease activity of intact and lysed bacteria and the effect of urea on the membrane potential. We also determined ureI expression, urease activity, and the effect of urea on membrane potential of several gastric and nongastric Helicobacter species. ureI was found to be present in the genome of the gastric Helicobacter species and absent in the nongastric Helicobacter species studied, as determined by PCR. Likewise, Western blot analysis confirmed that UreI was expressed only in the gastric Helicobacter species. When UreI is present, acidic medium pH activation of cytoplasmic urease is found, and urea addition increases membrane potential at acidic pH. The addition of a low concentration of detergent raised urease activity of intact bacteria at neutral pH to that of their homogenates, showing that urease activity was membrane limited. No acidic pH activation or urea induced membrane potential changes were found in the nongastric Helicobacter species. The ureI gene product is probably a pH activated urea transporter or perhaps regulates such a transporter as a function of periplasmic pH.

Bacterial Proteins↗
PubMed2003

Glycoconjugate binding of gastric and enterohepatic Helicobacter spp.

Helicobacter pylori is able to utilize several lectin-like, protein-carbohydrate interactions for binding to mucins, cell surfaces, and extracellular matrix proteins. As determined by hemagglutination assays and binding of radiolabeled bacteria to glycosphingolipids on thin-layer chromatograms, strains of gastric helicobacters and enterohepatic helicobacters, including Helicobacter canis, Helicobacter hepaticus, and Helicobacter bilis, also demonstrated evidence for the presence of lectin-hemagglutinin adhesins. In addition, in H. hepaticus and H. bilis, binding may be sialic acid dependent. The presence or absence and differences in the levels of activity of lectin adhesins may reflect the species' ecological niche.

Animals↗
PubMed1996

Prevalence and varieties of Helicobacter species in dogs from random sources and pet dogs: animal and public health implications.

Gastric bacteria of a variety of ultrastructural morphologies have been identified in or isolated from domestic carnivores, but their prevalence in different populations of animals and their clinical significance are still unknown. The purposes of this study were (i) to evaluate the prevalence and morphologic types of gastric bacterial in three different populations of dogs; (ii) to determine which of the organisms were culturable, and if the cultured organisms were morphologically similar to the organisms seen in situ; (iii) to identify the isolated organisms; and (iv) to determine if gastric bacteria were associated with gastritis. Three groups of dogs were examined: healthy laboratory dogs, healthy dogs from an animal shelter, and pet dogs with various nongastric illnesses. Of these, 100% of laboratory and shelter dogs and 67% of pet dogs were colonized by large, tightly coiled gastric spiral bacteria morphologically similar to Gastrospirillum hominis or Helicobacter felis (referred to as gastrospirilla). Regardless of the presence or density of gastric bacteria, all of the dogs in the study except one had mild to moderate gastritis. Helicobacter spp. were isolated from only 6 of 39 stomachs cultured, and only three of the organisms isolated were morphologically similar to the bacteria seen in situ. Five helicobacters were identified by 16S rDNA (genes coding for rRNA) sequence analysis. Three were strains of H. felis, one was H. bilis, and one was a novel helicobacter morphologically similar to "Flexispira rappini." Gastrospirilla are almost universal in the stomachs of domestic dogs, and in most infected dogs, they do not appear to be associated with clinical signs or histologic lesions compared with uninfected dogs. Nongastrospirillum helicobacters are rare in dogs and are not histologically detectable. Helicobacter pylori was not isolated from domestic dogs.

Animals↗