Influence of Helicobacter pylori infection on in vitro responsiveness of gastric fundus to agonists and to stimulation of enteric nerves in Mongolian gerbils

2002 ◽  
Vol 37 (8) ◽  
pp. 589-595 ◽  
Author(s):  
Yusuke Takehara ◽  
Yohei Mizuta ◽  
Hajime Isomoto ◽  
Ken Ohnita ◽  
Masaya Yoshimura ◽  
...  
Antibiotics ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 845
Author(s):  
Candace Goodman ◽  
Katrina N. Lyon ◽  
Aitana Scotto ◽  
Cyra Smith ◽  
Thomas A. Sebrell ◽  
...  

Helicobacter pylori infection is commonly treated with a combination of antibiotics and proton pump inhibitors. However, since H. pylori is becoming increasingly resistant to standard antibiotic regimens, novel treatment strategies are needed. Previous studies have demonstrated that black and red berries may have antibacterial properties. Therefore, we analyzed the antibacterial effects of black and red raspberries and blackberries on H. pylori. Freeze-dried powders and organic extracts from black and red raspberries and blackberries were prepared, and high-performance liquid chromatography was used to measure the concentrations of anthocyanins, which are considered the major active ingredients. To monitor antibiotic effects of the berry preparations on H. pylori, a high-throughput metabolic growth assay based on the Biolog system was developed and validated with the antibiotic metronidazole. Biocompatibility was analyzed using human gastric organoids. All berry preparations tested had significant bactericidal effects in vitro, with MIC90 values ranging from 0.49 to 4.17%. Antimicrobial activity was higher for extracts than powders and appeared to be independent of the anthocyanin concentration. Importantly, human gastric epithelial cell viability was not negatively impacted by black raspberry extract applied at the concentration required for complete bacterial growth inhibition. Our data suggest that black and red raspberry and blackberry extracts may have potential applications in the treatment and prevention of H. pylori infection but differ widely in their MICs. Moreover, we demonstrate that the Biolog metabolic assay is suitable for high-throughput antimicrobial susceptibility screening of H. pylori.


2008 ◽  
Vol 43 (1) ◽  
pp. 32-37 ◽  
Author(s):  
Chao-Hung Kuo ◽  
Huang-Ming Hu ◽  
Pei-Yun Tsai ◽  
Sheau-Fang Yang ◽  
Lin-Li Chang ◽  
...  

2020 ◽  
Vol 13 ◽  
pp. 175628482096873
Author(s):  
Javier P. Gisbert

Although susceptibility-guided therapy is frequently recommended for Helicobacter pylori infection, the evidence available to date supporting this strategy is limited. The aim of the present article is to review the advantages and limitations of the susceptibility-guided and the empirical strategies to treat this infection. We performed a bibliographic search to identify studies investigating H. pylori susceptibility-guided therapy. Culture is not the only way to assess antibiotic resistance, as different polymerase chain reaction-based approaches have been developed as alternative methods. For detecting H. pylori antimicrobial resistance, a molecular approach based on a stool sample might enable more convenient, time-saving methods. Unfortunately, the antimicrobial susceptibility cannot be obtained in all cases. Furthermore, antibiotic susceptibility testing in clinical practice yields useful information only for a few antibiotics: clarithromycin, metronidazole, and quinolones. In addition, susceptibility towards clarithromycin and metronidazole in vitro does not necessarily lead to eradication in vivo. In the case of H. pylori therapy failure, we should not re-administer any of the antibiotics against which H. pylori has probably become resistant. Our updated meta-analysis showed that susceptibility-guided treatment is not better than empirical treatment of H. pylori infection in first-line therapy if the most updated quadruple regimens are empirically prescribed, and similar efficacy results were also demonstrated with the two strategies for second-line therapy. Cumulative H. pylori eradication rate with several successive rescue therapies empirically prescribed reaches almost 100%. Finally, the studies that have evaluated the cost-effectiveness of the susceptibility-guided treatment have achieved contradictory results. In summary, we can conclude that the evidence is too limited to support the generalized use of susceptibility-guided therapy for H. pylori treatment in routine clinical practice, either as first-line or as rescue treatment. Nevertheless, it would be recommended that susceptibility tests are performed routinely, even before prescribing first-line treatment, in specialized centers with an interest in H. pylori management.


2005 ◽  
Vol 73 (3) ◽  
pp. 1820-1827 ◽  
Author(s):  
David J. McGee ◽  
Melanie L. Langford ◽  
Emily L. Watson ◽  
J. Elliot Carter ◽  
Yu-Ting Chen ◽  
...  

ABSTRACT Helicobacter pylori causes disease in the human stomach and in mouse and gerbil stomach models. Previous results have shown that motility is critical for H. pylori to colonize mice, gerbils, and other animal models. The role of chemotaxis, however, in colonization and disease is less well understood. Two genes in the H. pylori chemotaxis pathway, cheY and tlpB, which encode the chemotaxis response regulator and a methyl-accepting chemoreceptor, respectively, were disrupted. The cheY mutation was complemented with a wild-type copy of cheY inserted into the chromosomal rdxA gene. The cheY mutant lost chemotaxis but retained motility, while all other strains were motile and chemotactic in vitro. These strains were inoculated into gerbils either alone or in combination with the wild-type strain, and colonization and inflammation were assessed. While the cheY mutant completely failed to colonize gerbil stomachs, the tlpB mutant colonized at levels similar to those of the wild type. With the tlpB mutant, there was a substantial decrease in inflammation in the gerbil stomach compared to that with the wild type. Furthermore, there were differences in the numbers of each immune cell in the tlpB-mutant-infected stomach: the ratio of lymphocytes to neutrophils was about 8 to 1 in the wild type but only about 1 to 1 in the mutant. These results suggest that the TlpB chemoreceptor plays an important role in the inflammatory response while the CheY chemotaxis regulator plays a critical role in initial colonization. Chemotaxis mutants may provide new insights into the steps involved in H. pylori pathogenesis.


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