Library

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    Is the Association Between Helicobacter pylori and Gastric Cancer Confined to CagA-Positive Strains? (2004)
    Oxford, UK : Blackwell Science Ltd
    Helicobacter 9 (2004), S. 0 
    Details
    ISSN: 1523-5378
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: Background.  Infection with Helicobacter pylori is associated with an increased risk of gastric cancer. Several studies have indicated that the association differs with strain type. We aimed to find out if infection with strains lacking the virulence factor CagA is linked to gastric cancer risk.Materials and methods.  In a hospital-based case–control study, we collected sera from 100 case patients with a newly diagnosed gastric adenocarcinoma and 96 control patients with diseases unrelated to H. pylori status. Antibodies to H. pylori were analyzed by enzyme-linked immunosorbent assay (ELISA), and antibodies to CagA were detected by immunoblot. Logistic regression was used to obtain odds ratios (ORs) as estimates of relative risk, adjusted for potential confounding.Results.  Among the case patients, 81% were ELISA positive and 86% had antibodies to CagA. The corresponding numbers among the controls were 58% and 55%, respectively. ELISA positivity was associated with an increased risk of gastric adenocarcinoma compared to ELISA negativity (OR for gastric cancer regardless of site 3.9, 95% CI 1.9–8.2). The OR was 7.4 (95% CI 3.3–16.6) for CagA-positive relative to CagA-negative subjects. Among ELISA-positive subjects the presence of CagA antibodies increased the risk 3.6 times (95% CI 1.2–11.1). ELISA-positive CagA-negative infections were associated with a fourfold increased risk (OR = 4.2, 95% CI 1.0–17.0) compared to no infection (ELISA-negative and CagA-negative).Conclusions.  Although patients with antibodies to CagA have the greatest risk of developing gastric cancer, those with CagA-negative infections run a significantly greater risk than uninfected persons.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1083-4389.2004.00222.x
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Helicobacter pylori Entry into Human Gastric Epithelial Cells: A Potential Determinant of Virulence, Persistence, and Treatment Failures (2000)
    Boston, MA, USA : Blackwell Science Ltd
    Helicobacter 5 (2000), S. 0 
    Details
    ISSN: 1523-5378
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: Background and Objectives. Intracellular location of Helicobacter pylori in human gastric epithelial cells has been observed in biopsies. Whether this reflects an ability to invade host cells and establish an intracellular niche remains to be determined.Methods. The interactions between a clinical isolate of H. pylori and primary cell cultures from human gastric epithelium or the human epithelial cell line HEp-2 were monitored using time-lapse photography. This technique allows studies of the dynamics of host-microbial interactions.Results. H. pylori cells readily approached and established close contacts with epithelial cells followed by uptake of the bacteria into the cellular cytoplasm. Entry into epithelial cells was achieved through an active process of bacterial motility and penetration of the cell membranes. In conventional invasion assays using HEp-2 cells, an increased internalization in a strain producing the vacuolating cytotoxin was observed, compared to the isogenic VacA knockout mutant.Conclusion. Invasion of gastric epithelium represents a hitherto unappreciated trait of H. pylori that could contribute to the bacterium's ability to establish persistent infection that evades the mucosal immune defense and sometimes also antimicrobial therapy. A small number of bacterial cells with a transient intracellular habitat could serve as a seeder population, providing a backup for a constantly challenged and fluctuating luminal population.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1046/j.1523-5378.2000.00023.x
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Combination Treatment with Ranitidine Is Highly Eff icient Against Helicobacter pylori Despite Negative Impact of Macrolide Resistance (1997)
    Cambridge, MA, USA : Blackwell Science, Inc.
    Helicobacter 2 (1997), S. 0 
    Details
    ISSN: 1523-5378
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: This double-blind, randomized study evaluated the efficacy of dual and triple therapies including ranitidine for treatment of Helicobacter pylori infection.〈section xml:id="abs1-2"〉〈title type="main"〉Materials and Methods.Dyspeptic patients (n = 105) with a positive rapid urease test formed the intention-to-treat population (ITT). All patients were assigned to 14 days treatment with ranitidine 300 mg b.i.d and clarithromycin 750 mg b.i.d. Group A (n = 53) also received a placebo twice daily, while group B (n = 52) received lymecycline 300 mg b.i.d. Treatment with ranitidine, 150 mg b.i.d, was continued for an additional 30 days. H. pylori infection was verified by culture. Twelve weeks after antibiotic treatment, H. pylori status was investigated by culture and 14C-urea breath test (UBT). The per-protocol (PP) group consisted of 73 patients (A, n = 38; B, n = 35).〈section xml:id="abs1-3"〉〈title type="main"〉Results.Cure rates were 87% (95% C.I. = 72% to 94%) vs. 72% (95% C.I. = 58% to 83%) in the ITT-group and 89% (95% C.I. = 73% to 97%) vs. 87% (95% C.I. = 72% to 96%) in the PP-population (culture and UBT) when triple and dual therapies were compared. In all patients who were not cured, clarithromycin resistance of H. pylori was acquired. Side effects were experienced by 54% of patients.〈section xml:id="abs1-4"〉〈title type="main"〉Conclusions.The difference in efficacy between the two treatment regimens was not significant. However, the cure rates in this study are comparable to combination treatments with omeprazole. Treatment failures were due to acquired clarithromycin resistance.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1523-5378.1997.06085.pp.x
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Egg Passage of Rodshaped and Coccoid Forms of Helicobacter pylori: Preliminary Studies (1996)
    Oxford, UK : Blackwell Publishing Ltd
    Helicobacter 1 (1996), S. 0 
    Details
    ISSN: 1523-5378
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: Background.We used egg passage of bacteria stored in water to evaluate the culturability of the coccoid form of Helicobacter pylori, as a complement to the results obtained from various animal models. Egg passage was performed, as it is a simple, rapid, and well-characterized old method by which to culture and evaluate culturability of bacteria compared to experiments in animal models. Egg passage has been used in such experiments since 1938 for isolation and growth of, for example, Rickettsiae sp. and Chlamydia sp. Materials and Methods.The rod-shaped form of H. pylori was produced by plate cultures for 4 and 7 days. The coccoid form of H. pylori was produced by culture on agar plates for 10 days, followed by storage in water. These preparations then were inoculated into the yolk sac of differently aged fertilized eggs. Results.Positive culture was obtained from 14 of 17 eggs (82%) inoculated with rod-shaped H. pylori compared to 0 of 22 eggs (0%) inoculated with the coccoid form. Conclusion. Culturability of H. pylori is reduced when it converts into the coccoid form produced by starvation and age followed by storage in water for several weeks at room temperature. Egg passage did not raise the culturability of the coccoid form of H. pylori. Our study demonstrates some clear differences between fresh rods and stored cocci forms of H. pylori in terms of culturability when passed through eggs.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1523-5378.1996.tb00036.x
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Rapid Combined Characterization of Microorganism and Host Genotypes using a Single Technology (2004)
    Oxford, UK : Blackwell Science Ltd
    Helicobacter 9 (2004), S. 0 
    Details
    ISSN: 1523-5378
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: Background.  Genetic information is becoming increasingly important in diagnosis and prognosis of infectious diseases. In this study we investigated the possibility of using a single technology, the Pyrosequencing™ technology (Biotage AB, Uppsala, Sweden), to gather several kinds of important genetic information from the human pathogen Helicobacter pylori, as well as from the carrier of the H. pylori infection.Materials and Methods.  DNA from 87 clinical isolates of H. pylori, 50 isolates from H. pylori-infected transgenic mice and nine gastric biopsies from H. pylori-infected patients was analyzed for targets in the 16S rRNA, 23S rRNA and cytotoxin associated gene A (cagA) genes to determine species identity, clarithromycin susceptibility and virulence level, respectively. In addition, three single nucleotide polymorphisms in the human interleukin-1B (IL-1B) gene, reported to affect the risk of developing gastric cancer, were analyzed in the gastric biopsy samples.Results.  All DNA targets were processed and analyzed in parallel, enabling convenient genetic characterization of both pathogen and host. All genotypes were easily and accurately assigned. In the 16S rRNA analysis, 99.83% of the bases were correctly called.Conclusions.  We conclude that genetic analysis using Pyrosequencing™ technology was nonlaborious, and gave highly accurate data for different kinds of target. We therefore believe that this technology has the potential to complement or in the future substitute the time-consuming traditional microbial identification and typing methods, as well as enabling rapid typing of relevant host genetic markers.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1083-4389.2004.00210.x
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    An anthroposophic lifestyle and intestinal microflora in infancy (2002)
    Berlin, Germany : Munksgaard International Publishers
    Pediatric allergy and immunology 13 (2002), S. 0 
    Details
    ISSN: 1399-3038
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: The intestinal flora is considered to have an impact on the development of the immune system. In the anthroposophic lifestyle, a diet comprising vegetables spontaneously fermented by lactobacilli, and a restrictive use of antibiotics, anti-pyretics and vaccinations, is typical. The aim of this study was to assess the gut flora in infants in relation to certain lifestyle characteristics associated with anthroposophy. Sixty-nine children 〈 2 years of age with an anthroposophic lifestyle, and 59 infants of a similar age with a traditional lifestyle, were clinically examined and questionnaire replies assessed. Fecal samples were analyzed by bacterial enumeration, bacterial typing through biochemical fingerprinting and by measuring microflora-associated characteristics (MACs). The numbers of colony-forming units (CFU)/g of feces were significantly higher for enterococci and lactic acid bacteria in children who had never been exposed to antibiotics (5.5 × 107 vs. 2.1 × 107; p 〈 0.001 and 10 × 107 vs. 4.1 × 107; p 〈 0.01, respectively). Furthermore, the number of enterococci was significantly higher in breastfed and vegetarian infants (p 〈 0.01). The diversity (Simpson's diversity index) of lactobacilli, as determined by biochemical fingerprinting, was higher in infants born at home than in those born in hospital (p 〈 0.01). Several MACs were related to specific lifestyle features, and infants with an anthroposophic lifestyle had a higher proportion of acetic acid and a lower proportion of propionic acid in their stool as compared to the control children. In conclusion, lifestyle factors related to the anthroposophic way of life influenced the composition of the gut flora in the infants. These differences may contribute to the lower prevalence of atopic disease previously observed in children in anthroposophic families.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1034/j.1399-3038.2002.01062.x
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    In Vitro Aging of Helicobacter pylori: Changes in Morphology, Intracellular Composition and Surface Properties (1999)
    Boston, MA, USA : Blackwell Science Ltd
    Helicobacter 4 (1999), S. 0 
    Details
    ISSN: 1523-5378
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: During the conversion from the bacillary into the coccoid form, Helicobacter pylori organisms are known to change extensively. The aim of this study was to determine some of the changes that occur regarding morphology, intracellular composition and surface properties during the aging of bacteria in vitro.〈section xml:id="abs1-2"〉〈title type="main"〉Materials and Methods. H. pylori from agar plate cultures of different ages was used in this study. The intracellular composition of the two morphological forms of the bacteria was tested by density centrifugation, DNA extraction and quantitative OD, mRNA and ATP measurements. Immunoblotting was used to observe changes in secreted/superficial protein patterns, and hydrophobicity measurements were used to observe changes in surface properties.〈section xml:id="abs1-3"〉〈title type="main"〉Results.All bacillary H. pylori organisms changed morphology gradually over 10 days of culture. Rods had a higher density than cocci; bacteria stored in PBS had the highest density and bacteria stored in water had the lowest. The quantitative DNA, RNA and ATP content were reduced in the aging bacteria. Fewer immunogenic proteins were expressed, and an increased surface hydrophobicity was observed in the older cultures.〈section xml:id="abs1-4"〉〈title type="main"〉Conclusion.This study highlights several aspects of H. pylori aging in vitro and shows some of the differences that exist between bacillary and coccoid forms. This information is important for understanding the transmission and survival of H. pylori outside the human host, as the degradative changes in the intracellular composition and the surface properties shown here point to dead bacteria, and not to a viable but nonculturable form.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1046/j.1523-5378.1999.09034.x
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Bacterium–host interactions monitored by time-lapse photography (1997)
    [s.l.] : Nature Publishing Group
    Nature medicine 3 (1997), S. 930-931 
    Details
    ISSN: 1546-170X
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Medicine
    Notes: [Auszug] Any experimental system for measuring bacterial virulence has two parts: The bacterium itself and the host analog. Although animal models are the gold standard of research on bacterial virulence mechanisms, animals present a complex system in which many variables cannot be controlled. To study ...
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1038/nm0897-930
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    13C-urea breath test results in pigs challenged with Helicobacter pylori or other urease producing bacteria (1999)
    Oxford, UK : Blackwell Publishing Ltd
    FEMS immunology and medical microbiology 23 (1999), S. 0 
    Details
    ISSN: 1574-695X
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology , Medicine
    Notes: The gastric bacterial flora and its influence on the 13C-urea breath test (UBT) for detection of Helicobacter pylori infection was studied in a pig model. Seven SPF minipigs were used. H. pylori or a mix of other urease positive bacteria were administered orally. UBT, serum and biopsies for histology and culture were collected. Our results show that UBT is not specific for H. pylori in pigs as the gastric bacterial flora is responsible for the high UBT values observed. Furthermore, the Ellegaard Göttingen SPF minipigs are not useful in an animal model for H. pylori studies.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1574-695X.1999.tb01246.x
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    pH-dependent binding of Helicobacter pylori to pig gastric mucins (1999)
    Oxford, UK : Blackwell Publishing Ltd
    FEMS immunology and medical microbiology 24 (1999), S. 0 
    Details
    ISSN: 1574-695X
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology , Medicine
    Notes: A microtiter-based assay was developed to study the binding of Helicobacter pylori to pig gastric mucins purified by density-gradient centrifugation in CsCl/4 M guanidinium chloride. Binding of H. pylori was observed over the ‘mucin’ band as well as with ‘low-density’ components in the gradients, and binding to the latter was more pronounced when incubations were performed at 37°C as compared to 20°C. At a lower pH, binding of H. pylori (strain SVA 40) to the ‘high-density’ mucins from pig antrum was increased but binding to the ‘low-density’ ones was decreased. Binding of the P466 strain (Leb-specific) was mainly associated with the ‘mucin’ band, whereas the MO19 strain reacted preferentially with the ‘low-density’ components. In summary, H. pylori may bind to gastric mucins and the binding is influenced by temperature, pH and the repertoire of bacterial adhesins.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1574-695X.1999.tb01279.x
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...