ArticleAlimentary pharmacology & therapeutics2012
The effects of varying acidity on Helicobacter pylori growth and the bactericidal efficacy of ampicillin.
Article in Alimentary pharmacology & therapeutics, 2012. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 49 papers, 1 of them a synthesis that pooled it.
What it found
Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.
The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.
Who cites it
49 citing papers in PubMed, 1 synthesis or guideline pooled it, 103 citations in OpenAlex.
- Efficacy of second-line regimens forBMJ open gastroenterology · 2020Pooled it
- Randomized Trial Comparing Esomeprazole and Rabeprazole in First-line Eradication Therapy for Helicobacter pylori Infection based on the Serum Levels of Pepsinogens.Internal medicine (Tokyo, Japan) · 2017Trial
- One-day front-loading with four doses of rabeprazole followed by a standard twice-daily regimen provides sufficient acid inhibition in extensive metabolizers of CYP2C19.European journal of clinical pharmacology · 2015Trial
- Trial
- Trial
- Vonoprazan-Containing Triple Therapy Based on Clarithromycin Susceptibility May Be Definitive Treatment Strategy for Eradication ofJGH open : an open access journal of gastroenterology and hepatology · 2026Article
- Role of Vonoprazan-Amoxicillin Dual Therapy in Pediatric RefractoryACG case reports journal · 2025Article
- Vonoprazan in Helicobacter pylori treatment regimens in India: Dawn of a New Era.Indian journal of gastroenterology : official journal of the Indian Society of Gastroenterology · 2025Article
- Comparative efficacy and safety of vonoprazan versus esomeprazole-based high-dose dual therapies for first-lineTherapeutic advances in gastroenterology · 2025Article
- Nanomaterials: A Prospective Strategy for Biofilm-FormingInternational journal of nanomedicine · 2025Review
- In Vitro Susceptibility and Synergistic Effect of Bismuth AgainstAntibiotics (Basel, Switzerland) · 2024Article
- Article
- Review
- Evolving Concepts in Helicobacter pylori Management.Gastroenterology · 2024Review
- GERD: Latest update on acid-suppressant drugs.Current research in pharmacology and drug discovery · 2024Article
- Biofilm ofAntibiotics (Basel, Switzerland) · 2023Review
- Expectations for the Dual Therapy with Vonoprazan and Amoxicillin for the Eradication ofJournal of clinical medicine · 2023Review
- Intraluminal Therapy forBiomedicines · 2023Article
- 14-day pantoprazole- and amoxicillin-containing high-dose dual therapy forFrontiers in pharmacology · 2023Article
- Implications of the paradigm shift in management ofTherapeutic advances in gastroenterology · 2023Review
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
5 authors at 3 institutions in 2 countries.
Funding
Abstract
backgroundPenicillins inhibit cell wall synthesis; therefore, Helicobacter pylori must be dividing for this class of antibiotics to be effective in eradication therapy. Identifying growth responses to varying medium pH may allow design of more effective treatment regimens.
aimTo determine the effects of acidity on bacterial growth and the bactericidal efficacy of ampicillin.
methodsH. pylori were incubated in dialysis chambers suspended in 1.5-L of media at various pHs with 5 mM urea, with or without ampicillin, for 4, 8 or 16 h, thus mimicking unbuffered gastric juice. Changes in gene expression, viability and survival were determined.
resultsAt pH 3.0, but not at pH 4.5 or 7.4, there was decreased expression of ~400 genes, including many cell envelope biosynthesis, cell division and penicillin-binding protein genes. Ampicillin was bactericidal at pH 4.5 and 7.4, but not at pH 3.0.
conclusionsAmpicillin is bactericidal at pH 4.5 and 7.4, but not at pH 3.0, due to decreased expression of cell envelope and division genes with loss of cell division at pH 3.0. Therefore, at pH 3.0, the likely pH at the gastric surface, the bacteria are nondividing and persist with ampicillin treatment. A more effective inhibitor of acid secretion that maintains gastric pH near neutrality for 24 h/day should enhance the efficacy of amoxicillin, improving triple therapy and likely even allowing dual amoxicillin-based therapy for H. pylori eradication.
Indexed as
Identifiers
What OpenQuestion holds
Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.