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specific detection of campylobacter jejuni and campylobacter coli by using polymerase chain reaction.development of a routine detection assay for campylobacter jejuni and campylobacter coli in clinical specimens was undertaken by using the polymerase chain reaction (pcr). an oligonucleotide primer pair from a conserved 5' region of the flaa gene of c. coli vc167 was used to amplify a 450-bp region by pcr. the primer pair specifically detected 4 strains of c. coli and 47 strains of c. jejuni; but it did not detect strains of campylobacter fetus, campylobacter lari, campylobacter upsaliensis, cam ...19921400961
characteristics of helicobacter pylori variants selected for urease deficiency.the urease of helicobacter pylori is suspected to play a role in the pathogenesis of gastritis. although all clinical isolates of h. pylori are urease positive (u+), we have selected and characterized several spontaneously arising urease-negative (u-) variants from wild-type strain 60190. urease-negative variants were identified by growth in medium containing 60 mm urea and arose at a frequency of 10(-5) to 10(-6). the urease activity of the wild-type strain inhibited growth of this strain in th ...19921500174
identification and purification of a cpn60 heat shock protein homolog from helicobacter pylori.helicobacter pylori is associated with gastritis and peptic ulcer disease in humans. we have identified a homolog of the chaperonin cpn60 family of heat shock proteins in h. pylori, referred to as hp54k. hp54k, purified from water-extractable h. pylori proteins, migrated as a single band at 54 kda by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. its native molecular mass was 740 kda; thus, hp54k apparently comprises a 14-mer. the n-terminal 33 residues of hp54k exhibited 60.6, 57.6, ...19921563786
the glycerolipid receptor for helicobacter pylori (and exoenzyme s) is phosphatidylethanolamine.we have previously shown that helicobacter pylori specifically binds to a glycerolipid species preferentially found in the antrum of the human stomach. we now show by high-pressure liquid chromatographic analysis that this species is a form of phosphatidylethanolamine and that h. pylori specifically binds to bona fide phosphatidylethanolamine as detected by a thin-layer chromatogram overlay procedure. considerable variation in the binding of h. pylori to phosphatidylethanolamine from different s ...19921587616
[helicobacter pylori].helicobacter pylori (hp) are gram-negative spiral bacteria which occur in the human stomach. the bacteria were cultured in vitro for the first time in 1983. it is suspected that the bacteria may cause chronic gastritis of type b and may also be a contributory cause of chronic ulceration and cancer of the stomach. the bacteria are accompanied by characteristic inflammatory changes in the gastric mucosa. the significance for gastritis, chronic ulceration, non-ulcer dyspepsia and carcinoma of the s ...19921632004
soluble surface proteins from helicobacter pylori activate monocytes/macrophages by lipopolysaccharide-independent mechanism.the inflammatory lesions associated with helicobacter pylori gastritis and duodenitis contain large numbers of mononuclear cells. the close proximity of h. pylori to gastric mucosa suggests that the organism interacts with mononuclear cells, thereby modulating the inflammatory response. to investigate the role of monocytes/macrophages in this response, we examined the effect of whole h. pylori bacteria, h. pylori surface proteins, and h. pylori lipopolysaccharide (lps) on purified human monocyte ...19911847939
characterization of the helicobacter pylori urease and purification of its subunits.helicobacter pylori (formerly campylobacter pylori) is the causative agent of gastritis in man. helicobacter pylori cells contain a large amount of an extremely active urease (e.c.3.5.1.5). this enzyme is suspected to be a virulence factor since the ammonium ion produced from urea may be responsible for tissue injury and/or survival of h. pylori in the gastric environment. helicobacter pylori urease, native relative molecular mass approximately 600,000, was purified by agarose gel filtration and ...19911857197
new small animal model for human gastric helicobacter pylori infection: success in both nude and euthymic mice.in order to develop an experimental rodent model, we administered 2 ml (10(8) organisms/ml) broth culture of any of four human isolated strains of helicobacter pylori by the oral route on a one-time basis to both balb/c nude and balb/c euthymic mice. after 20-wk examination, we have successfully demonstrated that the gastric mucosa of nude mice was continuously, and that of euthymic mice, temporarily (for 2 wk), colonized by orally administered, freshly isolated strains obtained from humans with ...19911951236
paf-acether synthesis by helicobacter pylori.clinical studies suggest that helicobacter pylori may play a role in the pathogenesis of gastroduodenal ulcers in man but direct evidence of mucosal injury by this microorganism is still lacking. paf-acether (paf) causes a number of disorders including ischaemic bowel necrosis and gastroduodenal ulceration. since paf is produced by escherichia coli, we investigated whether it could be synthesised by h pylori. five h pylori isolates were collected from antral biopsy specimens from patients with g ...19902253906
soluble and cell-associated haemagglutinins of helicobacter (campylobacter) pylori.some plate-grown strains of helicobacter (campylobacter) pylori that were harvested into phosphate-buffered saline and left for 1 h released soluble haemagglutinins. these caused high-titre agglutination of human and guinea-pig erythrocytes, whereas chicken, sheep and bovine erythrocytes were agglutinated at various titres. six of 10 strains which had been subcultured repeatedly did not possess soluble haemagglutinins. slide agglutination of bacterial suspensions demarcated the strains into two ...19902258915
antigenicity of fractions of helicobacter pylori prepared by fast protein liquid chromatography and urease captured by monoclonal antibodies.the antigenicity of helicobacter pylori protein fractions separated by fast protein liquid chromatography size exclusion was investigated by eia with sera from patients of well defined helicobacter pylori status. the antigenic material of helicobacter pylori was confined to fractions 8 and 14 to 21. urease containing fractions (14/15) and flagella containing fractions (17/18) were identified. fraction 8 non-specifically bound human immunoglobulin as demonstrated by the binding of helicobacter py ...19902261918
helicobacter pylori urease activity is toxic to human gastric epithelial cells.a human gastric adenocarcinoma cell line was used to evaluate the contribution of urease from helicobacter (formerly campylobacter) pylori to its cytotoxicity. gastric cells cultured in medium supplemented with 20 mm urea were exposed to 5 x 10(6) cfu of h. pylori per ml with or without the addition of a urease inhibitor, acetohydroxamic acid. viabilities of cells exposed to h. pylori for 2, 24, and 48 h, assessed by incorporation of neutral red dye, were 60, 27, and 16%, respectively; however, ...19902341188
tightly spiral shaped bacteria in the human stomach: another cause of active chronic gastritis?tightly spiral shaped gram negative bacteria were seen in the gastric biopsies obtained from two patients undergoing gastroscopy. active chronic gastritis was present in both patients and one patient also had gastric ulceration. attempts to culture the organism by a number of methods were unsuccessful but positive urease results were obtained in both patients. both patients were treated with colloidal bismuth subcitrate. biopsies taken after treatment showed resolution of infection and histologi ...19902311971
characterization of and human serologic response to proteins in helicobacter pylori broth culture supernatants with vacuolizing cytotoxin activity.helicobacter pylori infection is strongly associated with histologic gastritis and peptic ulcer disease. broth culture supernatants from a subset of h. pylori strains induce vacuolization in cultured cells, a phenomenon that has been attributed to cytotoxin activity. concentrated culture supernatants from 15 of 28 (53.6%) h. pylori strains tested induced vacuolization in hela cells in titers ranging from 1:10 to 1:180. sodium dodecyl sulfate-polyacrylamide gel electrophoresis and silver staining ...19902307514
simultaneous streptococcus pneumoniae, giardia lamblia and campylobacter pylori infection: an adult presentation of x-linked hypogammaglobulinaemia.primary x-linked (bruton's) hypogammaglobulinaemia is uncommon. it usually presents clinically within the first two years of life--typically after the age of three months when maternal igg is exhausted. its diagnosis in middle life is exceptional. the presentation of the condition as a triple infection in a middle-aged man therefore seemed worthwhile reporting, as effective and safe prophylactic immunotherapy is now available.19892638574
biochemical changes induced by campylobacter pylori in the gastric juice.the biochemical changes induced in the gastric juice by the presence of campylobacter pylori (cp) were followed up in 151 patients with various gastric and duodenal diseases. the diagnosis of cp infection was made by the urease test. in the presence of cp urea decreased in the gastric juice and ammonia increased. the sialic acid, fucose and hexoses, glucide components of the mucus glycoproteins dissolved in the gastric juice, underwent no change in the presence of cp. the hexosamines in the gast ...19902270423
helicobacter pylori infection in patients with acquired immune deficiency syndrome.a controlled study was conducted on patients with human immunodeficiency virus (hiv) infection referred for upper endoscopy to evaluate the prevalence of helicobacter pylori (h. pylori) infection. four different stains and culture for h. pylori were performed on biopsy specimens from the gastric antrum. sixteen (40%) of 40 patients with acquired immune deficiency syndrome (aids) or aids-related complex (arc) were diagnosed to be infected with h. pylori versus 14 (39%) of 36 age-matched control p ...19902252020
evaluation of two monkey species (macaca mulatta and macaca fascicularis) as possible models for human helicobacter pylori disease.endoscopic, histologic, and microbiologic evaluations of 21 cynomolgus and 34 rhesus monkeys for naturally occurring helicobacter pylori infection were done. h. pylori was never isolated from any cynomolgus monkey, but was found in 12 rhesus monkeys. a general correlation existed between a positive culture and a gastric inflammatory response. inoculation challenges were then undertaken. four cynomolgus and five rhesus monkeys received two different h. pylori strains isolated from humans. five rh ...19902229353
gastrointestinal function and structure in hiv-positive patients.we examined 19 patients (17 men) with human immunodeficiency virus (hiv) infection and gastrointestinal symptoms to determine whether those symptoms were due to either a gastrointestinal tract infection or a defect in mucosal absorption because of an enteropathy. the erythrocyte folate and serum vitamin b12 levels were within normal limits in all of the patients. the serum ferritin level was elevated in 12. the xylose absorption test results were abnormal in 8 of the 13 patients able to complete ...19902207920
[gastritis c, non-a non-b and the sydney system: european unification or tower of babel?].the isolation of helicobacter pylori from the human stomach has changed the insights into the mechanisms of chronic gastritis. the altered concepts are reflected in newly developed classification systems. in 1989 distinction of the types a, b and c of chronic gastritis was proposed as a working formulation. in this classification type a gastritis is an autoimmune disease with antibodies against parietal cells and intrinsic factor. it is limited to the body of the stomach and may be complicated b ...19912030784
characterization of risk factors for helicobacter pylori infection among men attending a sexually transmitted disease clinic: lack of evidence for sexual transmission.the mechanism of transmission of helicobacter pylori is unknown. to investigate the role of sexual behavior and demographic factors in the acquisition of h. pylori infection, we evaluated the seroprevalence of antibody to h. pylori in 370 men attending an urban sexually transmitted diseases clinic. sera from the following three groups were analyzed by enzyme-linked immunosorbent assay for h. pylori-specific immunoglobulin g: 78 human immunodeficiency virus (hiv)-seropositive homosexual men, 102 ...19911939565
effect of age on gastric acid secretion and serum gastrin concentrations in healthy men and women.the effects of age on basal, meal-stimulated, and human gastrin-17-stimulated gastric acid secretion rates and serum pepsinogen concentrations were evaluated in 41 healthy men and women. older subjects (ages 44-71 years; mean, 57 years) had higher mean basal, meal-stimulated, and gastrin-17-stimulated acid secretory rates and basal serum pepsinogen i and ii concentrations than younger subjects (ages 23-42 years; mean, 33 years). age-related differences in acid secretion were especially prominent ...19911889722
neutrophil activation by helicobacter pylori.helicobacter pylori infection of the stomach is accompanied by a persistent polymorphonuclear leukocyte (pmnl) infiltrate of the mucosa. the aim of this work was to study the activation of human pmnl by substances produced by h pylori. filtered h pylori conditioned media stimulated a significant pmnl oxidative burst (p less than 0.002). this was equal to 26% of the maximal response stimulated by the pmnl chemotactic peptide n-formyl-methionyl-leucyl-phenylalanine (fmlp, 1 mumol/l). the response ...19911885065
gamma delta t cell receptor-positive cells of the human gastrointestinal mucosa: occurrence and v region gene expression in heliobacter pylori-associated gastritis, coeliac disease and inflammatory bowel disease.t cells expressing the gamma delta heterodimer of the t cell receptor (tcr) were studied with respect to their occurrence and expression of gamma delta tcr variable region (v) genes in the normal gastrointestinal mucosa and in a variety of inflammatory conditions. in controls, gamma delta tcr+ cells were a minority population confined to the epithelial compartment of stomach, small bowel and colonic mucosae. unlike in the periphery, gastro-intestinal gamma delta tcr+ intraepithelial lymphocytes ...19911828397
interaction of campylobacter pyloridis with human immune defence mechanisms.the in-vitro susceptibility to host immune defence mechanisms of campylobacter pyloridis was investigated. c. pyloridis was sensitive to antibody-dependent complement-mediated bactericidal activity of serum. the bacteria were phagocytosed and efficiently killed by polymorphonuclear neutrophils in the presence of serum opsonins. serum opsonin depletion studies indicated that an intact classical complement pathway was required for optimal phagocytic killing.19873585959
in vitro susceptibility of campylobacter pyloridis to cimetidine, sucralfate, bismuth and sixteen antibiotics.the in vitro susceptibility of recent danish human clinical isolates of campylobacter pyloridis to cimetidine, sucralfate, bismuth subsalicylate and sixteen antimicrobial agents was determined by an agar-dilution technique. benzylpenicillin was the most active drug (mic90 = 0.1 microgram/ml); ampicillin, erythromycin, gentamicin and ciprofloxacin were slightly less active. all strains were resistant to 100 micrograms sulfamethizole, and nalidixic acid also had little activity on weight basis. of ...19873591312
spiral organisms: what are they? a microbiologic introduction to helicobacter pylori.the stomach provides a hostile environment to most microorganisms owing to the antibacterial effect of gastric acidity. however, over the period of mammalian evolution a highly specialized group of bacteria has evolved to inhabit the gastric mucosa. the common features of these bacteria that allow survival in the stomach and colonization of their natural ecologic niche, mucus, are a specialized form of motility, microaerophilism, and very high activity of the enzyme urease. other important adapt ...19911775930
genetic organization and enzymatic activity of a superoxide dismutase from the microaerophilic human pathogen, helicobacter pylori.helicobacter pylori (hp) is a microaerobic human pathogen that has been implicated as a factor in the development of chronic type-b gastritis, gastric ulcers and gastric carcinoma. the enzyme superoxide dismutase (sod), a major defense mechanism against oxidative damage, catalyzes the breakdown of superoxide radicals to hydrogen peroxide and dioxygen. a search for sod genes in hp, employing pcr, revealed that this bacterium contained at least one sod gene. we cloned and sequenced a sod from this ...19947515365
ability of bacteria associated with chronic inflammatory disease to stimulate e-selectin expression and promote neutrophil adhesion.porphyromonas gingivalis, pseudomonas aeruginosa, and helicobacter pylori have been shown to be associated with adult periodontal disease, chronic lung infections, and peptic ulcers, respectively. the ability of these bacteria to stimulate e-selectin expression and promote neutrophil adhesion, two components necessary for the recruitment of leukocytes in response to infection, was investigated. little or no stimulation of e-selectin expression was observed with either p. gingivalis or h. pylori ...19957534275
expression of adhesion molecules on human granulocytes after stimulation with helicobacter pylori membrane proteins: comparison with membrane proteins from other bacteria.type b gastritis in its active form is characterized by a dense infiltration of the lamina propria with granulocytes. since the bacterium helicobacter pylori does not invade the epithelial barrier, a signaling pathway chemoattractive for granulocytes must exist across this mucosal boarder. one possible mechanism tested was whether granulocytes are directly activated by water-soluble membrane proteins (wsp) from h. pylori. these findings were compared with the effects of wsp from other bacteria ( ...19957540595
adhesion of helicobacter pylori to human gastric mucosal biopsy specimens cultivated in vitro.the therapeutic advances in helicobacter pylori infection is hampered by the lack of suitable animal model systems. we have previously reported on successful adherence of h. pylori to pig gastric mucosa cultured in vitro. the aim of this study was to verify the technique in human biopsy specimens cultured in vitro. mucosal samples were taken from h. pylori-negative and h. pylori-positive patients undergoing gastric surgery. the non-infected tissue was infected with h. pylori in vitro, and the in ...19911754854
a 35-year-old man with epigastric pain. 19957629961
compositional analysis of helicobacter pylori rough-form lipopolysaccharides.sodium dodecyl sulfate-polyacrylamide gel electrophoresis was used to analyze the macromolecular heterogeneity of lipopolysaccharides (lps) from seven fresh clinical isolates and three culture collection strains of the human pathogen helicobacter pylori. all the clinical isolates produced smooth-form lps with o side chains of relatively homogeneous chain length, whereas the culture collection strains yielded rough-form lps. a better yield of the latter lps was obtained when combined protease pre ...19921735724
direct polymerase chain reaction test for detection of helicobacter pylori in humans and animals.we designed a polymerase chain reaction (pcr) for amplifying the helicobacter pylori gene encoding 16s rrna. primers for the specific detection of h. pylori were designed for areas of the 16s rrna gene in which there is the least sequence homology between h. pylori and its closest relatives. the specificity of detection was confirmed by ensuring that the primers did not amplify dna extracts from the campylobacters h. cinaedi, h. mustelae, and wolinella succinogenes, which are the closest relativ ...19911723072
different effect of helicobacter pylori on the human gastric antral and body mucosal intracellular mucin.to elucidate the role of helicobacter pylori infection in the pathogenesis of gastric ulcer, we investigated the intracellular mucin content by measuring the periodic acid-schiff-alcian blue (pas-ab)-stained substances, by means of computer, in the biopsy sample of gastric mucosa from patients with and without h. pylori infection. in the antral mucosa the intracellular pas-ab-stained mucin content was significantly smaller in patients with infection than in patients without infection, whereas in ...19901702231
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
inhibition of human gastric cyclic amp production by helicobacter pylori protein--possible involvement of mucosal prostaglandin e2.the effect of helicobacter pylori protein on camp and prostaglandin (pge2) production was studied in incubates of human gastric fundic mucosa. at 24 hours, specimens incubated in the control fluid had a median camp value of 81 pmol/mg protein, compared to 28 pmol/mg (p less than 0.05) when incubated in h. pylori protein, 155 pmol/kg (p less than 0.006) in histamine, and 23 pmol/kg (p less than 0.05) in histamine plus h. pylori protein. a similar trend was observed at 48 hours. although h. pylori ...19911663793
adherence of helicobacter pylori to hep-2 cells.the adherence of 25 strains of helicobacter pylori was evaluated in hep-2 cells. these bacterial isolates, obtained from chilean patients with gastric disorders, were also tested for haemagglutination of human red blood cells. adherence of hep-2 cells was expressed as a common property of all strains, irrespective of whether the cultures were grown on semi-solid or in liquid media. previous reports that haemagglutinating activity was present in cells grown only on semi-solid media were confirmed ...19921602147
effect of sucralfate on the degradation of human gastric mucus by helicobacter pylori protease and lipases.among the factors implicated in the weakening of mucus perimeter of gastric mucosal defense is helicobacter pylori, the pathogenic action of which appears to be exerted through the elaborated protease and lipase enzymes. we present evidence that the activities of these enzymes are inhibited by an antiulcer agent, sucralfate. the grown colonies of bacteria were washed with saline, filtered through sterilization filter, and the filtrate used as the enzyme source. in the absence of sucralfate, the ...19921595646
omeprazole therapy for helicobacter pylori infection.to determine whether omeprazole eradicates helicobacter pylori infection of the gastric antrum, six adolescents and one adult with h. pylori colonization of the antrum were entered into a clinical, open trial of medical therapy. histologic evidence of antral gastritis and three complementary methods to document h. pylori colonization of the stomach (silver stain, urease testing, and culture of antrum) were obtained before and after an 8-week course of omeprazole. in vitro susceptibility to omepr ...19921475617
helicobacter pylori, gastritis, and ulcers in pediatrics.hp now appears to be more than a simple commensal organism in patients with gastritis or peptic ulcer disease. microbiologic, serologic, and epidemiologic studies all confirm that hp has an important role in children with abdominal pain. hp is found in the gastric mucosa of children with histologically proven gastritis or peptic ulcer. the organism can be transmitted from human to human with evidence of colonization, appearance of gastritis, and serum antibody response. antimicrobial therapy dir ...19921442315
mechanism of helicobacter pylori pathogenesis: focus on mucus.although the clinical data provide increasingly convincing indications that helicobacter pylori (h. pylori) is a causative factor in gastritis and peptic ulcer, the advances toward the clear understanding of this bacterium's pathogenic action are slow in coming. having a niche bordering two major perimeters of gastric mucosal defense, h. pylori is capable of exerting detrimental effects on the mucus layer, as well as surface cells of the gastric epithelium. to cause such an effect, the bacteria ...19921378466
molecular typing of helicobacter pylori by chromosomal and plasmid dna organization.diverse strains of helicobacter pylori were examined in order to initiate a molecular epidemiological typing scheme for this agent of human gastritis. twelve differently-sized plasmids from 1.8 to 63 kbp were identified in those strains harbouring extrachromosomal dna. recombinant dna probes were cloned randomly from the chromosome of the (plasmid-free) type strain (nctc 11637), and used to probe genomic southern blots for restriction site variation in and around homologous loci. genus-specific ...19921356227
[helicobacter pylori is a globally spread bacterium causing gastritis in man]. 19902362499
effect of a campylobacter pylori protein on acid secretion by parietal cells.the uptake of [14c]-aminopyrine by rabbit gastric epithelial cells was used as an indirect assay for acid secretion from parietal cells. campylobacter pylori strains, isolated from the stomachs of 3 patients with chronic gastritis, duodenal ulcer, and near-normal mucosa, respectively, inhibited acid secretion as effectively as 10(-4) mol/l cimetidine. the inhibition occurred with whole organisms and with sonicates. preliminary characterisation suggested that the inhibition was due to a nondialys ...19892568521
[rapid detection and easy culture of campylobacter pylori from human gastric mucosa].96 gastric mucosal biopsy specimens collected at endoscopy and placed into 3 ml 20% glucose were examined histologically, microscopically (gram staining), by urease test, and by cultivation. the rate of positive findings ws 62.5% by urease test, 34.4% by cultivation, and 27.0% microscopically. by using simple selective solid media, the number of positive cultivations increased to 58.7%. positive microbiological findings were established by one of three microbiological methods at a high percentag ...19892655826
review of the modes of action of colloidal bismuth subcitrate.in recent years considerable progress has been made to elucidate the modes of action of colloidal bismuth subcitrate (cbs). cbs accelerates the healing of experimental chronic ulcers in rats by the formation of occlusive complexes and/or the accumulation of epidermal growth factor (egf) in the ulcer crater. cbs exhibits gastric protection (cytoprotection) against, for example, ethanol lesions. microscopic analysis of these lesions reveals that cbs protects against deep mucosal necrosis but not s ...19892665050
no cultural detection of helicobacter pylori in dental plaque.helicobacter pylori causes human type b gastritis and is involved in the etiology of peptic ulcer disease. the routes of transmission of h. pylori are still unclear. the microorganism may be transmitted orally, since h. pylori has been detected in dental plaques. to confirm the hypothesis that dental plaques are a reservoir of h. pylori, 100 dental plaque specimens from 55 dental surgery patients were incubated on one nonselective and up to four selective agar media for the detection of h. pylor ...19947803925
examination of human stomach biopsies, saliva, and dental plaque for campylobacter pylori.to examine possible sources of campylobacter pylori and to determine the routes by which it is transmitted to the human stomach, samples of dental plaque and saliva from 71 patients undergoing endoscopy in addition to stomach biopsies were collected and cultured on selective noninhibitory skirrow medium. a total of 29 (40.8%) of the stomach biopsies yielded c. pylori. none of the saliva samples and only one of the dental plaque samples was found positive for c. pylori, and thus neither saliva no ...19892754008
non campylobacter pylori spiral organisms in the gastric antrum.colonisation of the human gastric antrum with non campylobacter pylori spiral organisms is described. a moderately severe histological gastritis was present despite the fact that these organisms, in contrast to c. pylori, were not closely associated with the epithelial cell surface. although in vitro culture of the organisms was unsuccessful, in vivo culture was achieved in the mouse stomach. further study of these spiral organisms should provide important clues to the role of bacteria in upper ...19892764819
monotherapy or polychemotherapy in the treatment of campylobacter pylori-related gastroduodenal disease.three pilot studies were performed to evaluate the efficacy of bismuth subsalicylate (bss) and nitrofurantoin to eradicate campylobacter pylori colonization in man. nitrofurantoin 3 x 100 mg capsules for 10 days did not clear c. pylori in any of 13 patients, and neither did the combination of bss and nitrofurantoin suspension (0/6 patients). immediately after high dose bss therapy 3 x 900 mg for 28 days, 8/17 patients (47%) had negative cultures and rapid urease tests. there was recrudescence in ...19883166527
[campylobacter pylori-associated chronic gastritis: a new entity in gastroduodenal diseases?].clinical, morphological and immunological data in addition to animal studies clearly support the conclusion, that campylobacter pylori infection is a direct cause (sufficient condition) for chronic type b gastritic in man. c. pylori gastritis is primarily a histologic entity defined by the presence of a gastric mucosal cellular infiltrate and the histologic demonstration of typical curved bacilli. preliminary findings indicate, that this infection is not associated with a specific combination of ...19883280934
gastric campylobacter-like organisms, gastritis, and peptic ulcer disease.although the presence of gastric bacteria has been long established, the recognition and isolation of campylobacter pylori and similar organisms has opened a new era in the understanding of inflammatory gastroduodenal conditions. visualization or isolation of gastric campylobacter-like organisms (gclos) is significantly associated with histologic evidence of gastritis, especially of the antrum. correlation with peptic ulceration also exists but probably is due to concurrent antral gastritis. out ...19873297911
iatrogenic campylobacter pylori infection is a cause of epidemic achlorhydria.on a number of occasions, there have been descriptions of epidemic achlorhydria in subjects undergoing repeated gastric secretory studies, typically as part of research protocols. we observed a case in a 37-yr-old healthy man undergoing weekly gastric analyses, along with endoscopy and gastric biopsy, as part of a research protocol studying gastric adaptation to aspirin. in the middle of the 2nd wk of aspirin administration, he developed severe nausea and epigastric discomfort. aspirin administr ...19883414650
campylobacter pyloridis gastritis: the past, the present, and speculations about the future.campylobacter pyloridis infection of the stomach has been associated with gastric ulcer, duodenal ulcer, nonulcer dyspepsia, and gastritis. the etiological role of c. pyloridis in most of those conditions remains unclear. we reviewed what is known about c. pyloridis infections in man. considerable clinical data on c. pyloridis infections was available in older literature concerning gastritis and gastric urease. c. pyloridis causes a form of type b gastritis. in some individuals the acute infecti ...19873551584
primary non-hodgkin lymphoma of the gastric stump.patients with a history of gastroduodenal surgery for benign lesions are at increased risk of developing cancer of the gastric stump. the majority of malignant tumors arising in gastric remnants are adenocarcinomas, but a few of cases of malignant lymphoma have been reported as well. some recent studies have suggested that helicobacter pylori-associated gastritis may play a role in the pathogenesis of primary gastric lymphoma. we report a case of primary high grade polymorphic b-cell lymphoma (h ...19957479373
royal society of tropical medicine and hygiene meeting at manson house, london, 16 february 1995. aspects of helicobacter pylori infection in the developing and developed world. helicobacter pylori infection, nutrition and growth of west african infants.helicobacter pylori is probably the commonest bacterial infection of humankind. in adults, colonization of the stomach is associated with chronic gastritis and duodenal ulcer disease. however, children in the developing world acquire h. pylori soon after birth, and there is evidence that it plays a part, through suppression of the gastric acid barrier, in the pathogenesis of the syndrome of diarrhoea, malnutrition and growth failure. infants born of mothers who secrete milk with high levels of a ...19957570858
[helicobacter pylori infection in children].helicobacter pylori (hp) is a pathogen of human gastric mucosa and is considered as the major cause of chronic gastritis and duodenal ulcer disease recurrence. the prevalence rate of hp infection increases with age and is related to low socioeconomic status in childhood. childhood appears to be a high-risk period for hp infection. clinical and histological features of hp infection are variable and often moderate in children. this is probably due to both genetic and environmental factors. abdomin ...19957640761
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
prevalence of helicobacter pylori infection in subtypes of gastric cancer.although helicobacter pylori has already been declared a human carcinogen, the exact nature of the association with gastric cancer remains to be explored. the aim of this study was to determine if the association is confined to specific types of gastric cancer.19957657118
production of acute gastric erosions in the cat by individual human pepsins.1. differing amounts of human pepsins 1, 3 (pepsin a) and 5 (pepsin c or gastriscin) in aqueous hcl/nacl at ph 1.3 were placed in perspex rings on the exposed luminal surface of the perfused cat stomach to test for mucolytic and erosive activity in vivo, with the acid medium in control rings. 2. after incubation at 37 degrees c for 60 or 120 min, the test and control solutions were replaced by the same volume of each test or control solution containing 18 mg of aspirin and incubated for a furthe ...19957705000
early gastric cancer in a patient with menetrier's disease, lymphocytic gastritis and helicobacter pylori.to describe a patient with early gastric cancer, menetrier's disease, lymphocytic gastritis and helicobacter pylori infection.19957712313
helicobacter pylori: human pathogen or simply an opportunist? 19957715345
interleukin-8 response of gastric epithelial cell lines to helicobacter pylori stimulation in vitro.gastric infection with helicobacter pylori activates a mucosal inflammatory response by mononuclear cells and neutrophils that includes expression of cytokines interleukin-1 beta (il-1 beta), il-6, tumor necrosis factor alpha, and il-8. in this study, we analyzed the il-8 response of human gastric cancer cell lines (kato iii, ags, and mkn28) to h. pylori infection in vitro. il-8 mrna expression was detected by reverse transcription-pcr amplification of rna extracted from epithelial cells after i ...19957729872
treatment of helicobacter pylori infection.helicobacter pylori infects the human stomach and is associated with chronic gastritis, peptic ulcer disease and gastric cancer. most patients with peptic ulcers are infected with h pylori. these patients suffer a high relapse rate following initial healing of the ulcer with anti-secretory agents. the rate of relapse can be greatly diminished following successful eradication of the organism. although experience is still being accumulated, it is reasonable to use eradication therapy in any patien ...19957749079
electron microscopic study on the regenerating epithelium of the chronic gastric ulcer.specimens from 31 cases of human gastric ulcers and 3 ulcer scars obtained at surgery were studied by transmission and scanning electron microscopy. a layer of simple cuboidal epithelial cells arising at the margin of the gastric ulcer migrated toward the ulcer base. two types of regenerating epithelium (re) were found: gastric and intestinal cell types. the gastric cell type re originated from the gastric epithelium and was composed of immature cells which later matured to form primitive gastri ...19957757944
uptake site of lansoprazole, a proton pump inhibitor, in human fundic mucosa: possible relevance with fibroblast and helicobacter pylori.to clarify the mechanism of the effect of lansoprazole in the healing of human gastric ulcer, the uptake sites of lansoprazole were studied using endoscopically biopsied specimens from the margin of the gastric ulcer. the specimens were incubated in a medium containing 3h-lansoprazole for 5 or 15 min., postfixed with 1% osmic acid and embedded in epon. the semithin or ultrathin sections were made and radioautographic emulsion films were applied by the wire-loop method. 30 days after the incubati ...19957773126
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
helicobacter pylori: a human pathogen. 19957791469
interaction between helicobacter pylori and human gastric epithelial cells in culture: effect of antiulcer drugs.a human in vitro model to study the interaction between helicobacter pylori and gastric epithelial cells was developed using primary cultures of gastric mucosal cells (isolated from gastric biopsies or operative specimen and maintained in culture for 2 weeks) as well as the well-differentiated human gastric carcinoma cell line hm02, the undifferentiated gastric tumour cell line hm51, and the laryngeal epithelial cell line hep-2. primary cultures and all cell lines were exposed to seven isolates ...19947831386
positive correlation between h,k-adenosine triphosphatase autoantibodies and helicobacter pylori antibodies in patients with pernicious anemia.helicobacter pylori is a major cause of gastritis, and the parietal cell h,k-adenosine triphosphatase (atpase) is a major autoantigen in autoimmune atrophic corpus gastritis, which may eventually lead to pernicious anemia and/or neuropathy. whether the bacterium induces the autoimmune response is unknown.19947871374
the prevalence of helicobacter pylori positivity in human immunodeficiency virus-infected children.to investigate the prevalence of helicobacter pylori infection in pediatric patients infected with the human immunodeficiency virus, we sought to detect the presence of antibodies against this organism in 23 human immunodeficiency virus-infected children of central african ethnic origin by means of a second-generation enzyme-linked immunoassay (elisa) test for the detection of immunoglobulin g (igg) antibodies to helicobacter pylori (malakit helicobacter pylori, biolab, limal, belgium). they wer ...19947876996
micronutrients and cancer aetiology: the epidemiological evidence.micronutrient deficiencies occur most commonly in poor countries and, therefore, are most likely to be associated with cancers common in these countries. epidemiological studies are hampered by inaccurate measurement of micronutrient intake and by the correlations between intakes of many nutrients. the strongest evidence for a protective effect of micronutrients is for oesophageal cancer. the identity of the micronutrients is not certain, but may include retinol, riboflavin, ascorbic acid and zn ...19947886059
activation of human thp-1 cells and rat bone marrow-derived macrophages by helicobacter pylori lipopolysaccharide.the mechanism by which helicobacter pylori, which has little or no invasive activity, induces gastric-tissue inflammation and injury has not been well characterized. we have previously demonstrated that water-extracted proteins of h. pylori are capable of activating human monocytes by a lipopolysaccharide (lps)-independent mechanism. we have now compared activation of macrophages by purified lps from h. pylori and from escherichia coli. lps was prepared by phenol-water extraction from h. pylori ...19957890370
serum levels of pepsinogen i in healthy volunteers and patients with gastric ulcers and gastric carcinoma in taiwan.in order to investigate the clinical usefulness of human pepsinogen i (pgi) as a noninvasive diagnostic tool for gastric lesions, 92 healthy volunteers, 87 patients with a gastric ulcer and 94 patients with gastric carcinoma, verified by histologic examinations, were enrolled. the serum level of pgi in each patient was measured by radioimmunoassay. mean serum pgi levels were 95.4 +/- 39.4 ng/ml in patients with gastric ulcers, 77.6 +/- 29.3 ng/ml in healthy volunteers, and 52.1 +/- 26.5 ng/ml in ...19937904845
gastrin and somatostatin in helicobacter pylori infected antral mucosa.helicobacter pylori infection is associated with increased meal stimulated gastrin secretion, but the reason for this is unknown. sequence specific radioimmunoassays were used to measure the concentration of alpha-amidated gastrin, the total progastrin product, and somatostatin in biopsy specimens of human antral mucosa. the antral concentrations of alpha-amidated gastrin and of total progastrin products were significantly higher in h pylori infected patients than in those not infected by this o ...19947911115
helicobacter and human cancer. 19947932804
[helicobacter pylori and gastroduodenal disease].gastroduodenal infection by helicobacter pylori is a known cause of many gastric and duodenal disorders. infection by h. pylori is very frequent ant its prevalence increases with age by about 1% per year. human-to-human transmission appears probable. h. pylori lives under the mucous layer of gastric-type epithelium. it is the main causal agent of chronic diffuse superficial gastritis (type b). after several decades lesions of superficial gastritis can evolve to atrophic gastritis. spontaneous sh ...19947939299
helicobacter pylori prevalence in endoscopy and medical staff.the epidemiology and mode of transmission of helicobacter pylori is currently unclear; it is postulated that the human stomach is the natural reservoir and that spread occurs by faecal-oral or oral-oral transmission. the aim of this study was to assess the prevalence of h. pylori in gastroenterologists and gastroenterology nurses compared with internists, general nurses and the normal population. an enzyme-linked immunosorbent assay technique (sensitivity 96%, specificity 88%) was used to detect ...19947948812
rebamipide, a novel antiulcer agent, attenuates helicobacter pylori induced gastric mucosal cell injury associated with neutrophil derived oxidants.the effect of rebamipide, a novel antiulcer compound, on helicobacter pylori activated neutrophil dependent in vitro gastric epithelial cell injury was investigated. luminol dependent chemiluminescence (chl), which detects toxic oxidants from neutrophils exhibited a 12-fold increase when the bacterial suspension of h pylori was added to the isolated human neutrophils. this change was significantly attenuated by rebamipide at a concentration less than 1 mm, showing that rebamipide may inhibit oxi ...19947959190
[helicobacter pylori: pathogens, pathomechanisms and epidemiology].h. pylori organisms are microaerophilic gram-negative curved or spiral bacteria that live in the mucus layer of the gastric epithelium. since the discovery of h. pylori similar organisms have been found in humans (h. cinaedi, h. fennelliae, h. heilmanii) and animals. h. pylori causes chronic active gastritis and is an important factor in the development of peptic ulceration and gastric cancer. narrow host range, tissue specificity and chronic inflammation are characteristic features. putative vi ...19947975667
genetic diversity of the helicobacter pylori haemagglutinin/protease (hap) gene.helicobacter pylori has been associated with the etiology of gastritis, gastric and duodenal ulcers and gastric cancer in man. in this study we confirm the presence of the haemagglutinin/protease (hap) gene in ten geographically diverse strains of h. pylori, but the southern analysis of genomic dna suggested that the location of the hap gene was different in each strain. we suggest that the hap gene is subject to a high rate of mutation and subsequent polymorphisms by virtue of a mobile, genetic ...19947988885
gastrospirillum hominis-associated gastritis: the first reported case in japan.tightly coiled spiral micro-organisms (gastrospirillum hominis), distinct from helicobacter pylori, were found in the gastric mucosa of a 66-year-old man with a 4-month history of intermittent epigastric pain. the organisms were distributed in the antral mucosa, which showed erosive gastritis; histologically, the affected mucosa presented moderate to severe chronic gastritis with focal neutrophil infiltration. after a 2-week administration of cimetidine, his symptoms resolved and the active infl ...19948012509
more convenient 13c-urea breath test modifications still meet the criteria for valid diagnosis of helicobacter pylori infection.13c-urea breath tests (ubt) were performed in 217 patients with epigastric symptoms to assess (a) the validity of shorter intervals of breath sample collection and (b) of the non-fasting state on diagnosing h. pylori infection and to evaluate (c) a more simple sampling method. (a) in 186 patients, breath samples were taken before and at 10, 20, 30, 40, 50, 60, 90, and 120 minutes after ingestion of 75 mg 13c-urea. 13c-enrichment was measured by isotope ratio mass spectrometry [delta/1000] and th ...19948017093
humoral and cellular immune recognition of helicobacter pylori proteins are not concordant.helicobacter pylori is a major cause of chronic antral gastritis and peptic ulcer disease. further definition is needed of the factors that determine whether infected individuals remain asymptomatic, or ultimately develop ulceration of the mucosa or transformation to malignancy. to explore the possibility that host response to h. pylori may play a role in the outcome of this infection, we have examined humoral and cellular recognition of several h. pylori proteins by seropositive and seronegativ ...19948033409
effect of helicobacter pylori on dbc-amp stimulated acid secretion by human parietal cells.this study examines the effect of different h.p. strains (a-d) on dbc-amp stimulated acid secretion by human parietal cells in vitro. h.p. strains a and d reduced acid secretion dose-dependently between 20 and 80%. in contrast, h.p. strains b and c had little or no effect. we conclude that h.p. strains vary in their ability to suppress acid secretion, and that the site of inhibition lies beyond the c-amp level, possibly involving the k+h(+)-atpase of the parietal cell. interference with acid sec ...19947721241
adhesion to and invasion of hela cells by helicobacter pylori.eight clinical isolates and two reference strains of helicobacter pylori were studied with regard to their interactions with hela cells. all the isolates adhered poorly to hela cells and the number of invasive bacteria was very low. no correlation was found between the adherence and invasiveness of the isolates on one hand, and the corresponding patients having ulcer or non-ulcer disease, or the ability of the strains to produce cytotoxin and to induce an oxidative burst of human polymorphonucle ...19957734829
characterization of a helicobacter pylori neutrophil-activating protein.helicobacter pylori-associated gastritis is mainly an inflammatory cell response. in earlier work we showed that activation of human neutrophils by a cell-free water extract of h. pylori is characterized by increased expression of neutrophil cd11b/cd18 and increased adhesiveness to endothelial cells. the work reported here indicates that the neutrophil-activating factor is a 150,000-molecular-weight protein (150k protein). neutrophil proadhesive activity copurified with this protein, which is a ...19957768601
protection by human milk iga against helicobacter pylori infection in infancy. 19938100892
animal model of human disease: lymphocytic gastritis.gastric specimens from 102 belonging to 11 different species were reviewed. of the 11 species, only the gastric mucosa of pigs contained a large number of lymphocytes in the surface and in the foveolar epithelium (mean 82 lymphocytes/1000 epithelial cells, range 62-128 lymphocytes. the gastric specimens of the remaining 10 species revealed none or occasional lymphocytes in the surface or the foveolar epithelium. the occurrence of intraepithelial lymphocytes in the gastric mucosa of pigs mimics t ...19938110991
glucose utilization and lactate production by helicobacter pylori.the transport and incorporation of d-glucose into the human pathogen helicobacter pylori was investigated employing radioactive tracer analysis and 1h and 13c nuclear magnetic resonance spectroscopy. the bacterium was found to utilize d-glucose contrary to the accepted view that it cannot catabolize carbohydrates. under the experimental conditions employed, the rate of transport of [14c]glucose was 3.24 mmol min-1 (g protein)-1, and the rate of incorporation into the cellular mass was 1.06 mumol ...19938126428
acute gastritis associated with spiral organisms from cats.numerous studies implicated helicobacter pylori as one causative agent producing gastritis and dyspepsia. recent reports focus on another bacterium, gastrospirillum hominis, as a possible pathogen producing gastritis. we report a 30-year-old researcher who became acutely ill with epigastric pain indicative of esophagitis or peptic ulcer disease. gastritis and a gastric ulcer were observed endoscopically. histological examination of the gastric mucosa revealed an acute gastritis and large spiral- ...19948149839
nonopsonic activation of neutrophils and cytotoxin production by helicobacter pylori: ulcerogenic markers.fifty-four clinical isolates of helicobacter pylori from human gastric biopsy specimens were tested for cytotoxin production, as determined by intracellular vacuolization of hela cells, and for the induction of oxidative burst in human polymorphonuclear leukocytes (pmnls), as measured by luminol-enhanced chemiluminescence (cl). nonopsonized, 20 of the h. pylori strains induced a rapid and strong cl response, in contrast to 30 other strains, which showed only weak and slow responses. another four ...19948171279
na+,k(+)-atpase of gastric cells. a target of helicobacter pylori cytotoxic activity.the present study shows a direct impairing action of a cytotoxin-producing helicobacter pylori strain on the na+,k(+)-atpase (evaluated as k(+)-dependent phosphatase activity) of human gastric epithelial cells in culture. the toxin itself is likely involved in this action which may also account for the cell edema found in vivo in helicobacter pylori-colonized stomach.19938224240
effects of cations on helicobacter pylori urease activity, release, and stability.the urease of helicobacter pylori is an important antigen and appears critical for colonization and virulence. several studies have indicated a superficial localization for the h. pylori urease, and the purpose of this study was to determine the effects of cations on the release and stability of urease activity from h. pylori cells. incubation of partially purified h. pylori urease in water containing 1, 5, or 10 mm ca2+, mg2+, k+, na+, edta, or egta [ethylene glycol-bis(beta-aminoethyl ether)-n ...19948262643
high prevalence of neutralizing activity to helicobacter pylori cytotoxin in serum of gastric-carcinoma patients.helicobacter pylori infection is causally related to chronic type-b gastritis, and may also be associated with an increased risk of gastric carcinoma. vacuolating cytotoxin, which is an 87-kda protein secreted by h. pylori, induces eukaryotic cell vacuolation in vitro. to determine whether there is an association between h. pylori vacuolating cytotoxin and gastric carcinoma, we investigated several characteristics of h. pylori infection, i.e., isolation of h. pylori from gastric biopsies, antibo ...19948262677
adherence of haemagglutinating helicobacter pylori to five cell lines.helicobacter pylori causes gastritis and is an important factor for the development of peptic ulcer disease in man. we used two different methods to examine the adhesion of nine h. pylori strains, with different haemagglutinating properties, to five cell lines, hela s3, hfi, vero, sw1222 and wehi cells. the adhesion studies were performed a) as bacterial adhesion to a monolayer of tissue culture cells, visualizing bacteria with fluorescein-isothiocyanate-labelled antibodies, b) as cell agglutina ...19938280930
serial change of gastric mucosa after challenging with helicobacter pylori in the cynomolgus monkey.the aim of this study was to clarify the change of the gastric mucosa following inoculation with helicobacter pylori (h. pylori). two pairs of cynomolgus monkeys received either h. pylori of human origin (group a) or h. pylori of monkey origin (group b) by intragastric inoculation at a dose of 10(9) cfu. after inoculation, endoscopical observation and biopsies were done every 7 days for one month. the bacteria in the biopsy samples were cultured quantitatively. the content of intracellular pas-a ...19938280957
chronic gastritis and helicobacter pylori in digestive form of chagas' disease.patients with the digestive form of chagas' disease frequently present chronic gastritis. as the microorganism helicobacter pylori is now accepted as the most common cause of human chronic gastritis, the present work was undertaken to verify a possible relationship between the presence of this bacterium and inflammatory changes of antral mucosa in chagasic patients. seventeen chagasics, with megaesophagus and or megacolon were studied. fragments from two different regions of antral mucosa were o ...19938284595
helicobacter pylori: isolation from gastric biopsy specimens.forty-two gastric biopsies, in two transport media, were homogenized and cultured on three media under micro-aerophilic conditions. brain-heart infusion agar with a commercial antibiotic supplement (giving 10 mg vancomycin, 5 mg trimethoprim and 2500 i.u. polymixin per litre) yielded the best results. ordinary chocolate (heated) human blood agar could be used in laboratories with limited resources. growth was obtained in 4-6 days at 37 degrees c. all isolates were sensitive to metronidazole. the ...19938311573
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