Ramiro Vilchez-Vargas

Background and Aims: Helicobacter pylori (H. pylori) is an obligate pathogen affecting approximately 50% of the world population. With rising antibiotic resistance rates in H. pylori and increasing dropout rates from eradication therapies due to adverse effects, H. pylori treatment is increasingly challenged. Saccharomyces boulardii (S. boulardii), a probiotic yeast, was shown to reduce infection- and therapy-associated adverse events and increase H. pylori eradication rates. Our meta-analysis summarizes the beneficial effects of S. boulardii supplementation on H. pylori eradication and therapy-associated side effects. Methods: We conducted a systematic literature review and meta-analysis on PubMed, Cochrane Library, and Google Scholar from inception (1993) to October 24, 2024. Research and analysis were performed in accordance with the ‘Preferred Reporting Items of Systematic Reviews and Meta-Analyses’ (PRISMA) guidelines. Results: The supplementation of S. boulardii to H. pylori therapy caused a significant increase in overall eradication rates and a significant decrease in overall diarrhea, nausea, and epigastric pain rates. Subgroup analysis showed that S. boulardii supplementation also decreased taste disturbance rates in patients receiving triple therapy. Symptoms, such as meteorism, vomiting, and urticaria/rash, were not significantly reduced through the supplementation of S. boulardii. Conclusions: S. boulardii was shown to be an effective add-on to H. pylori eradication therapy. Significant improvements in eradication and frequency of the most common adverse events were observed. However, more studies are needed to validate those findings for patients receiving bismuth-based quadruple therapy.

Soil microbiota plays an important role in cycling and storage of essential nutrients for plant development. Studies about the interaction between wild pepper (chiltepin) and soil microbiota are scarce. Chiltepin ( Capsicum annuum L. var. glabriusculum ) is considered a progenitor of the cultivated chili peppers with a source of genetic traits for genetic improvement of the cultivated pepper. The aim of this study was to analyze the bacterial composition by identifying the plant growth‐promoting rhizobacteria (PGPR) associated with wild and cultivated chiltepin plants, according to their location and season of the year. Wild pepper (chiltepin) habitat features contrasts throughout the year and could experience severe drought stress with high temperatures (dry season); despite this, the plant grows and yields fruits once the rain comes. These abiotic conditions make wild pepper and the associated microbiota an interesting system to study. Soil samples were collected during three seasons in 2017: dry, rainy, and post‐rainy, in four municipalities of Sonora state. Analyses of pH, temperature, and inorganic nitrogen pool fluxes were performed. The soil pH associated with the cultivated chiltepin remained constant (≈9), whereas a decreasing trend was observed across all wild pepper growing locations as precipitation increased (≈6.0). In addition, the bacterial metabolic characterization was carried out from 14 selected bacterial strains that had activity in indole acetic acid production, phosphate solubilization, and siderophore production. The most predominant genus found belonged to Bacillus sp., followed by Serratia sp., according to the 16S rRNA gene sequencing. Finally, we identified 7 isolated strains that could be considered as potential bacteria to be used in bioremediation processes and a core microbial community as a promising source of native PGPR strains associated to wild pepper chiltepin that did not differ from the geographical area and season of the year.

Anastomotic leakage (AL) is a potentially life-threatening complication following colorectal cancer (CRC) resection. In this study, we aimed to unravel longitudinal changes in microbial structure before, during, and after surgery and to determine if microbial alterations may be predictive for risk assessment between sufficient anastomotic healing (AS) and AL prior surgery. We analysed the microbiota of 134 colon mucosal biopsies with 16S rRNA V1-V2 gene sequencing. Samples were collected from three location sites before, during, and after surgery, and patients received antibiotics after the initial collection and during surgery. The microbial structure showed dynamic surgery-related changes at different time points. Overall bacterial diversity and the abundance of some genera such as Faecalibacterium or Alistipes decreased over time, while the genera Enterococcus and Escherichia_Shigella increased. The distribution of taxa between AS and AL revealed significant differences in the abundance of genera such as Prevotella, Faecalibacterium and Phocaeicola. In addition to Phocaeicola, Ruminococcus2 and Blautia showed significant differences in abundance between preoperative sample types. ROC analysis of the predictive value of these genera for AL revealed an AUC of 0.802 (p = 0.0013). In summary, microbial composition was associated with postoperative outcomes, and the abundance of certain genera may be predictive of postoperative complications.