scholarly journals Responses of Endoscopy Patients in Ladakh, India, to Helicobacter pylori Whole-Cell and CagA Antigens

2002 ◽  
Vol 9 (6) ◽  
pp. 1313-1317 ◽  
Author(s):  
Judith Romero-Gallo ◽  
Guillermo I. Pérez-Pérez ◽  
Richard P. Novick ◽  
Patrick Kamath ◽  
Tsering Norbu ◽  
...  
Keyword(s):  
Helicobacter Pylori ◽  
Immunoglobulin G ◽  
Human Stomach ◽  
Remote Area ◽  
Serum Immunoglobulin ◽  
Specific Enzyme ◽  
Whole Cell ◽  
Cell Antigen ◽  
The World ◽  
H Pylori

ABSTRACT Although Helicobacter pylori is a cosmopolitan colonizer of the human stomach, the responses among persons in remote populations from whom H. pylori was cultured have not been studied. We report on studies of 189 persons in the Ladakh region of India in whom serum immunoglobulin G responses to H. pylori whole-cell and CagA antigens were measured. H. pylori was isolated from 68 of these patients. An H. pylori whole-cell antigen derived from Ladakhi strains outperformed a similar antigen from U.S. strains, as determined by antigen-specific enzyme-linked immunosorbent assays. In total, 95% of the population was seropositive, including individuals responding only to the CagA antigen. Correlation with culture results showed that these were true positives and, therefore, that the H. pylori whole-cell serology was falsely negative in some cases. In addition to establishing a collection of H. pylori isolates from a remote area in the world, we show that use of H. pylori whole-cell and CagA serology together increases the sensitivity for the detection of colonization.

scholarly journals Mutational Analysis of Metronidazole Resistance in Helicobacter pylori

2005 ◽  
Vol 49 (3) ◽  
pp. 1236-1237 ◽  
Author(s):  
Jill M. Moore ◽  
Nina R. Salama
Keyword(s):  
Helicobacter Pylori ◽  
Mutational Analysis ◽  
Transposon Mutagenesis ◽  
Human Stomach ◽  
Metronidazole Resistance ◽  
H Pylori ◽  
Chromosomal Loci

ABSTRACT Metronidazole is one of a few antibiotics effective in eliminating Helicobacter pylori infection of the human stomach. Several chromosomal loci have been implicated in resistance to this drug. Saturation transposon mutagenesis of the H. pylori genome revealed inactivation of the rdxA gene as uniquely able to confer metronidazole resistance.

scholarly journals Helicobacter pylori is killed by nitrite under acidic conditions

Gut ◽  
1998 ◽  
Vol 42 (3) ◽  
pp. 334-337 ◽  
Author(s):  
R S Dykhuizen ◽  
A Fraser ◽  
H McKenzie ◽  
M Golden ◽  
C Leifert ◽  
...  
Keyword(s):  
Helicobacter Pylori ◽  
Anaerobic Bacteria ◽  
Antimicrobial Effect ◽  
Human Stomach ◽  
Bacterial Survival ◽  
Novel Host ◽  
Potassium Nitrite ◽  
Acidic Conditions ◽  
H Pylori ◽  
Facultative Anaerobic Bacteria

Background—Due to the expression of urease,Helicobacter pylori is able to establish itself in the human stomach under acidic conditions. A novel host defence mechanism was recently proposed, suggesting that the formation of salivary nitrite in symbiosis with facultative anaerobic bacteria in the oropharynx, is aimed at enhancing the antimicrobial activity of gastric juice.Aims—To investigate whether the addition of nitrite in physiological concentrations influences the resistance ofH pylori to acid.Methods—H pylori cultured from fresh gastric biopsy specimens was exposed for 30 minutes to normal saline and to HCl/KCl buffer (0.2M) at pH 2 with urea (5 mM) added. The influence of potassium nitrite (50–1000 μmol/l) on bacterial survival was determined.Results—Addition of nitrite (1 mM) to acidic solutions (pH 2) resulted in complete kill of H pyloriwithin 30 minutes exposure time whereas acid alone allowed the organism to survive (p<0.001). The antimicrobial effect of nitrite at pH 2 against H pylori was dose dependent and complete kill of organisms occurred at concentrations ⩾500 μmol/l.Conclusion—Acidified nitrite has antibacterial activity against H pylori. This should prompt further research into the effect of salivary nitrite on the survival of H pylori in the human stomach.

scholarly journals Helicobacter pylori–binding nonacid glycosphingolipids in the human stomach

2018 ◽  
Vol 293 (44) ◽  
pp. 17248-17266 ◽  
Author(s):  
Chunsheng Jin ◽  
Angela Barone ◽  
Thomas Borén ◽  
Susann Teneberg
Keyword(s):  
Helicobacter Pylori ◽  
Gastric Mucosa ◽  
Structural Complexity ◽  
Human Stomach ◽  
Carbohydrate Binding ◽  
Human Gastric Mucosa ◽  
H Pylori ◽  
Contrast Information

Helicobacter pylori has a number of well-characterized carbohydrate-binding adhesins (BabA, SabA, and LabA) that promote adhesion to the gastric mucosa. In contrast, information on the glycoconjugates present in the human stomach remains unavailable. Here, we used MS and binding of carbohydrate-recognizing ligands to characterize the glycosphingolipids of three human stomachs from individuals with different blood group phenotypes (O(Rh−)P, A(Rh+)P, and A(Rh+)p), focusing on compounds recognized by H. pylori. We observed a high degree of structural complexity, and the composition of glycosphingolipids differed among individuals with different blood groups. The type 2 chain was the dominating core chain of the complex glycosphingolipids in the human stomach, in contrast to the complex glycosphingolipids in the human small intestine, which have mainly a type 1 core. H. pylori did not bind to the O(Rh−)P stomach glycosphingolipids, whose major complex glycosphingolipids were neolactotetraosylceramide, the Lex, Lea, and H type 2 pentaosylceramides, and the Ley hexaosylceramide. Several H. pylori-binding compounds were present among the A(Rh+)P and A(Rh+)p stomach glycosphingolipids. Ligands for BabA-mediated binding of H. pylori were the Leb hexaosylceramide, the H type 1 pentaosylceramide, and the A type 1/ALeb heptaosylceramide. Additional H. pylori-binding glycosphingolipids recognized by BabA-deficient strains were lactosylceramide, lactotetraosylceramide, the x2 pentaosylceramide, and neolactohexaosylceramide. Our characterization of human gastric receptors required for H. pylori adhesion provides a basis for the development of specific compounds that inhibit the binding of this bacterium to the human gastric mucosa.

scholarly journals Expanding Allelic Diversity of Helicobacter pylori vacA

1998 ◽  
Vol 36 (9) ◽  
pp. 2597-2603 ◽  
Author(s):  
Leen-Jan van Doorn ◽  
Céu Figueiredo ◽  
Ricardo Sanna ◽  
Salvador Pena ◽  
Peter Midolo ◽  
...  
Keyword(s):  
Helicobacter Pylori ◽  
Direct Sequencing ◽  
Allelic Diversity ◽  
Pcr Primers ◽  
Epidemiological Studies ◽  
Sequence Alignments ◽  
Gene Encoding ◽  
The World ◽  
Probe Assay ◽  
H Pylori

The diversity of the gene encoding the vacuolating cytotoxin (vacA) of Helicobacter pylori was analyzed in 98 isolates obtained from different geographic locations. The studies focused on variation in the previously defined s and m regions ofvacA, as determined by PCR and direct sequencing. Phylogenetic analysis revealed the existence of four distinct types of s-region alleles: aside from the previously described s1a, s1b, and s2 allelic types, a novel subtype, designated s1c, was found. Subtype s1c was observed exclusively in isolates from East Asia and appears to be the major s1 allele in that part of the world. Three different allelic forms (m1, m2a, and m2b) were detected in the m region. On the basis of sequence alignments, universal PCR primers that allow effective amplification of the s and m regions from H. pyloriisolates from all over the world were defined. Amplimers were subsequently analyzed by reverse hybridization onto a line probe assay (LiPA) that allows the simultaneous and highly specific hybridization of the different vacA s- and m-region alleles and tests for the presence of the cytotoxin-associated gene (cagA). This PCR-LiPA method permits rapid analysis of the vacA andcagA status of H. pylori strains for clinical and epidemiological studies and will facilitate identification of any further variations.

scholarly journals RESISTANCE TO AMOXICILLIN, CLARITHROMYCIN AND CIPROFLOXACIN OF Helicobacter pylori ISOLATED FROM SOUTHERN BRAZIL PATIENTS

2014 ◽  
Vol 56 (3) ◽  
pp. 197-200 ◽  
Author(s):  
Simone Ulrich Picoli ◽  
Luiz Edmundo Mazzoleni ◽  
Heriberto Fernández ◽  
Laura Renata De Bona ◽  
Erli Neuhauss ◽  
...  
Keyword(s):  
Helicobacter Pylori ◽  
Eradication Therapy ◽  
Empirical Therapy ◽  
British Society ◽  
World Population ◽  
Southern Brazil ◽  
First Line ◽  
The World ◽  
Antibiotics Susceptibility ◽  
H Pylori

Introduction: Helicobacter pylori is a bacteria which infects half the world population and is an important cause of gastric cancer. The eradication therapy is not always effective because resistance to antimicrobials may occur. The aim of this study was to determine the susceptibility profile of H. pylori to amoxicillin, clarithromycin and ciprofloxacin in the population of Southern Brazil. Material and methods: Fifty four samples of H. pylori were evaluated. The antibiotics susceptibility was determined according to the guidelines of the British Society for Antimicrobial Chemotherapy and the Comité de l'Antibiogramme de la Société Française de Microbiologie. Results: Six (11.1%) H. pylori isolates were resistant to clarithromycin, one (1.9%) to amoxicillin and three (5.5%) to ciprofloxacin. These indices of resistance are considered satisfactory and show that all of these antibiotics can be used in the empirical therapy. Conclusion: The antibiotics amoxicillin and clarithromycin are still a good option for first line anti-H. pylori treatment in the population of Southern Brazil.

scholarly journals Helicobacter pylori Accumulates Photoactive Porphyrins and Is Killed by Visible Light

2005 ◽  
Vol 49 (7) ◽  
pp. 2822-2827 ◽  
Author(s):  
Michael R. Hamblin ◽  
Jennifer Viveiros ◽  
Changming Yang ◽  
Atosa Ahmadi ◽  
Robert A. Ganz ◽  
...  
Keyword(s):  
Helicobacter Pylori ◽  
Visible Light ◽  
Propionibacterium Acnes ◽  
Protoporphyrin Ix ◽  
Human Stomach ◽  
Drug Resistant ◽  
Violet Light ◽  
Resistant Strains ◽  
H Pylori ◽  
Drug Resistant Strains

ABSTRACT Helicobacter pylori colonizes the mucus layer of the human stomach and duodenum, causes chronic gastritis, gastric ulcer, and is a risk factor for gastric adenocarcinoma. There is a 20% failure rate in antibiotic therapy, which is increasingly due to antibiotic resistance and necessitates the search for alternative antimicrobial methods. We have discovered that H. pylori when cultured in liquid medium, accumulates significant quantities of coproporphyrin and protoporphyrin IX, both in the cells and secreted into the medium. These photoactive porphyrins lead to cell death (up to 5 logs) by photodynamic action upon illumination with low doses of visible light, with blue/violet light being most efficient. The degree of killing increases with the age of the culture and is greater than that found with Propionibacterium acnes (another bacterium known to be photosensitive due to porphyrin accumulation). Both virulent and drug-resistant strains are killed. The data suggest that phototherapy might be used to treat H. pylori infection in the human stomach.

scholarly journals Treatment of Helicobacter pylori infections in the light of the increase of antibiotic resistance

2018 ◽  
Vol 72 ◽  
pp. 143-158
Author(s):  
Eliza Mnich ◽  
Jakub Ibran ◽  
Magdalena Chmiela
Keyword(s):  
Fatty Acids ◽  
Ascorbic Acid ◽  
Helicobacter Pylori ◽  
Antibiotic Resistance ◽  
Eradication Therapy ◽  
The World ◽  
Potential Alternative ◽  
Resistant Strains ◽  
Treatment Mechanisms ◽  
H Pylori

The aim of this study was to present the risks associated with the occurrence of Helicobacter pylori (H. pylori) infection in humans and the problems related to eradication procedures with the use of antibiotic treatment. The content provides an overview of the available methods of infection diagnosis and recommended therapeutic schemes as well as potential alternative schedules of treatment. Mechanisms of H. pylori resistance to commonly used antibiotics including the mutations in the genome leading to resistance and the incidence of resistant strains in the world has been described. Finally, we introduced substances with some potential in eradication therapy, including probiotics, plant formulations as well as polyunsaturated fatty acids and ascorbic acid.

scholarly journals Role of Helicobacter pylori and Other Environmental Factors in the Development of Gastric Dysbiosis

Pathogens ◽  
2021 ◽  
Vol 10 (9) ◽  
pp. 1203
Author(s):  
Uriel Gomez-Ramirez ◽  
Pedro Valencia-Mayoral ◽  
Sandra Mendoza-Elizalde ◽  
Juan Rafael Murillo-Eliosa ◽  
Fortino Solórzano Santos ◽  
...  
Keyword(s):  
Environmental Factors ◽  
Microbial Communities ◽  
Optimal Growth ◽  
Human Stomach ◽  
Physiological Changes ◽  
Heterogeneous Habitat ◽  
The World ◽  
H Pylori ◽  
Gastric Microbiota

Microbiomes are defined as complex microbial communities, which are mainly composed of bacteria, fungi, and viruses residing in diverse regions of the human body. The human stomach consists of a unique and heterogeneous habitat of microbial communities owing to its anatomical and functional characteristics, that allow the optimal growth of characteristic bacteria in this environment. Gastric dysbiosis, which is defined as compositional and functional alterations of the gastric microbiota, can be induced by multiple environmental factors, such as age, diet, multiple antibiotic therapies, proton pump inhibitor abuse, H. pylori status, among others. Although H. pylori colonization has been reported across the world, chronic H. pylori infection may lead to serious consequences; therefore, the infection must be treated. Multiple antibiotic therapy improvements are not always successful because of the lack of adherence to the prescribed antibiotic treatment. However, the abuse of eradication treatments can generate gastric dysbiotic states. Dysbiosis of the gastric microenvironment induces microbial resilience, due to the loss of relevant commensal bacteria and simultaneous colonization by other pathobiont bacteria, which can generate metabolic and physiological changes or even initiate and develop other gastric disorders by non-H. pylori bacteria. This systematic review opens a discussion on the effects of multiple environmental factors on gastric microbial communities.

scholarly journals Effect of Helicobacter pylori infection on the course of nonalcoholic fatty liver disease

2019 ◽  
pp. 90-94
Author(s):  
L. B. Lazebnik ◽  
L. V. Tarasova ◽  
E. A. Komarova ◽  
E. I. Busalayeva
Keyword(s):  
Helicobacter Pylori ◽  
Liver Disease ◽  
Fatty Liver ◽  
Nonalcoholic Fatty Liver Disease ◽  
Fatty Liver Disease ◽  
Helicobacter Pylori Infection ◽  
Course Of Disease ◽  
Nonalcoholic Fatty Liver ◽  
The World ◽  
H Pylori

The prevalence of nonalcoholic fatty liver disease (NAFLD) in the world steadily increasеs, turning it into a most prevalent liver disease in the last decade. NAFLD is a multidisciplinary problem, it attracts the attention of specialists of different specialities. Especially interesting is the clarification of the main links of the pathogenesis of nonalcoholic fatty liver disease, including the effect of endogenous microflora on the occurrence and course of disease. Modern information is represented in the review, it confirm the association between Helicobacter pylori infection (H. pylori) and NAFLD. It has been proven that successful eradication of H. pylori detaines the fibrosis in the liver, reduces the level of proinflammatory markers, and improves insulin resistance.

Sign in / Sign up

Export Citation Format

Share Document