Lipopolysaccharides (LPSs) are bacterial surface glycolipids, produced by Gram-negative bacteria. LPS is known to determine acute inflammatory reactions, particularly in the context of sepsis. However, LPS can also trigger chronic inflammation. In this case, the source of LPS is not an external infection, but rather an increase in endogenous production, which is usually sustained by gut microbiota (GM), and LPS contained in food. The first site in which LPS can exert its inflammatory action is the gut: both GM and gut-associated lymphoid tissue (GALT) are influenced by LPS and shift towards an inflammatory pattern. The changes in GM and GALT induced by LPS are quite similar to the ones seen in IBD: GM loses diversity, while GALT T regulatory (Tregs) lymphocytes are reduced in number, with an increase in Th17 and Th1 lymphocytes. Additionally, the innate immune system is triggered, through the activation of toll-like receptor (TLR)-4, while the epithelium is directly damaged, further triggering inflammation. In this review, we will discuss the importance of the crosstalk between LPS, GM, and GALT, and discuss the possible implications.

Summary: Background : Helicobacter pylori eradication fails in about 10% of patients, particularly because of the occurrence of resistance to antibiotics and side‐effects. During anti‐H. pylori therapy, probiotics have been successfully used to reduce the incidence of side‐effects.Aim : To evaluate the effect of Bacillus clausii, a probiotic, on incidence (primary variable) and severity of antibiotic‐associated side‐effects during anti‐H. pylori therapy.Methods : One hundred and twenty H. pylori‐positive patients were randomly screened to receive: (i) a standard 7 days triple therapy with rabeprazole 20 mg b.d., clarithromycin 500 mg b.d. and amoxicillin 1 g b.d. and B. clausii t.d.s. (each preparation containing 2 × 10⁹ spores) for 14 days starting from the first day of treatment. (ii) The same 7 days triple therapy and placebo t.d.s. for 14 days starting from the first day of treatment. Side‐effects were assessed using a validated questionnaire and were recorded for 4 weeks from the start of therapy.Results : The incidences of nausea, diarrhoea and epigastric pain in patients treated with B. clausii were significantly lower than in placebo group, in both PP and ITT analysis. Equally, intensity of nausea and diarrhoea in patients treated with B. clausii was significantly lower than in placebo group. There were no differences in adherence to treatment and H. pylori eradication rates between groups.Conclusion : In symptom‐free, H. pylori‐positive subjects B. clausii bacteriotherapy reduces the incidence of the most common side‐effects related to anti‐H. pylori antibiotic therapy compared with placebo.

Sepsis is a serious organ dysfunction caused by a dysregulated immune host reaction to a pathogen. The innate immunity is programmed to react immediately to conserved molecules, released by the pathogens (PAMPs), and the host (DAMPs). We aimed to review the molecular mechanisms of the early phases of sepsis, focusing on PAMPs, DAMPs, and their related pathways, to identify potential biomarkers. We included studies published in English and searched on PubMed^® and Cochrane^®. After a detailed discussion on the actual knowledge of PAMPs/DAMPs, we analyzed their role in the different organs affected by sepsis, trying to elucidate the molecular basis of some of the most-used prognostic scores for sepsis. Furthermore, we described a chronological trend for the release of PAMPs/DAMPs that may be useful to identify different subsets of septic patients, who may benefit from targeted therapies. These findings are preliminary since these pathways seem to be strongly influenced by the peculiar characteristics of different pathogens and host features. Due to these reasons, while initial findings are promising, additional studies are necessary to clarify the potential involvement of these molecular patterns in the natural evolution of sepsis and to facilitate their transition into the clinical setting.

Background: One-week triple therapy is currently regarded as the reference of anti-Helicobacter pylori treatment. However, antibiotic-associated gastrointestinal side effects are among the major pitfalls of such regimens. Probiotic supplementation may be regarded as a therapeutic tool to prevent or reduce these troublesome drug-related manifestations. Aim: To determine whether the addition of the probiotic Lactobacillus GG to an anti-H. pylori standard triple therapy could help to prevent or minimize the occurrence of gastrointestinal side effects. Methods: One hundred and twenty healthy asymptomatic subjects screened positive for H. pylori infection and deciding to receive eradication therapy were randomized either to 1-week pantoprazole (40 mg b.i.d.), clarithromycin (500 mg b.i.d.), tinidazole (500 mg b.i.d.) or to the same regimen supplemented with Lactobacillus GG for 14 days. Patients filled in validated questionnaires during follow-up to determine the type and severity of side effects and to judge overall tolerability. Results: Bloating, diarrhea and taste disturbances were the most frequent side effects during the eradication week and were significantly reduced in the Lactobacillus GG-supplemented group (RR = 0.4, CI 0.2–0.8; RR = 0.3, CI 0.1–0.8; RR = 0.3, CI 0.1–0.7, respectively). The same pattern was observed throughout the follow-up period. Overall assessment of treatment tolerability showed a significant trend in favor of the Lactobacillus GG-supplemented group (p = 0.03). Conclusions:Lactobacillus GG supplementation beneficially affects H. pylori therapy-related side effects and overall treatment tolerance.