Helicobacter species binding to the human gastric mucosa

Helicobacter pylori infects half of the world population, being associated with several gastric disorders, such as chronic gastritis and gastric carcinoma. The Helicobacter genus also includes other gastric helicobacters, such as H. heilmannii¸ H. ailurogastricus, H. suis, H. felis, H. bizzozeronii, and H. salomonis. These gastric helicobacters colonize both the human and animal stomach. The prevalence of gastric non-Helicobacter pylori Helicobacter (NHPH) species in humans has been described as low, and the in vitro binding to the human gastric mucosa was never assessed. Herein, human gastric tissue sections were used for the evaluation of the tissue glycophenotype and for the binding of gastric NHPH strains belonging to different species. Histopathological evaluation showed that 37.5% of the patients enrolled in our cohort presented chronic gastritis, while the presence of neutrophil or eosinophilic activity (chronic active gastritis) was observed in 62.5% of the patients. The secretor phenotype was observed in 68.8% of the individuals, based on the expression of Lewis B antigen and binding of the UleX lectin. The in vitro binding assay showed that all the NHPH strains evaluated were able to bind, albeit in low frequency, to the human gastric mucosa. The H. heilmannii, H. bizzozeronii, and H. salomonis strains displayed the highest binding ability both to the gastric superficial epithelium and to the deep glands. Interestingly, we observed binding of NHPH to the gastric mucosa of individuals with severe chronic inflammation and intestinal metaplasia, suggesting that NHPH binding may not be restricted to the healthy gastric mucosa or slight chronic gastritis. Furthermore, the in vitro binding of NHPH strains was observed both in secretor and non-secretor individuals in a similar frequency. In conclusion, this study is the first report of the in vitro binding ability of gastric NHPH species to the human gastric mucosa. The results suggest that other glycans, besides the Lewis antigens, could be involved in the bacterial adhesion mechanism; however, the molecular intervenients remain unknown.

How Far Can Our Expectations Go on Revisional Bariatric Surgery After Failed Adjustable Gastric Banding?

PURPOSE

Bariatric surgery has proven its effectiveness in the treatment of obesity and related comorbidities. However, several procedures may be required to treat this chronic disease and/or complications after bariatric surgery. The most frequent revisional surgeries performed after failed laparoscopic adjustable gastric banding (AGB) have been Roux-en-Y gastric bypass (RYGB) and sleeve gastrectomy (SG). The aim of this study is to compare medium-term outcomes of primary and revisional bariatric procedures.

MATERIAL AND METHODS

Single institution, matched case-control study of obese patients submitted to bariatric surgery, divided into four groups of 50 patients: (A) primary RYGB; (B) primary SG; (C) revisional Roux-en-Y gastric bypass (rRYGB) after failed laparoscopic AGB; (D) revisional sleeve gastrectomy (rSG) after failed laparoscopic AGB. Demographic variables, surgical procedures characteristics and complications, weight loss outcomes and resolution of comorbidities were compared.

RESULTS

Mortality and morbidity were comparable between primary and revisional procedures. Weight loss outcomes were inferior in patients submitted to rRYGB when compared to those submitted to RYGB, with no significant differences found when comparing the other groups. Regarding comorbidities' outcomes, only patients submitted to rSG had lower odds of comorbidities' improvement. Patients submitted to rRYGB had an odd 7 times higher of comorbidities' improvement than those submitted to rSG, independent of weight loss outcomes.

CONCLUSION

Revisional surgeries are safe procedures with adequate weight loss outcomes in this difficult set of patients. The choice of revisional procedure may not influence weight loss outcomes, but rRYGB seems to be a better option regarding comorbidities' resolution.

Phase diagram and re-entrant fermionic entanglement in a hybrid Ising-Hubbard ladder

The degree of fermionic entanglement is examined in an exactly solvable Ising-Hubbard ladder, which involves interacting electrons on the ladder's rungs described by Hubbard dimers at half-filling on each rung, accounting for intrarung hopping and Coulomb terms. The coupling between neighboring Hubbard dimers is assumed to have an Ising-like nature. The ground-state phase diagram consists of four distinct regions corresponding to the saturated paramagnetic, the classical antiferromagnetic, the quantum antiferromagnetic, and the mixed classical-quantum phase. We have exactly computed the fermionic concurrence, which measures the degree of quantum entanglement between the pair of electrons on the ladder rungs. The effects of the hopping amplitude, the Coulomb term, temperature, and magnetic fields on the fermionic entanglement are explored in detail. It is shown that the fermionic concurrence displays a re-entrant behavior when quantum entanglement is being generated at moderate temperatures above the classical saturated paramagnetic ground state.

Spotlight on esophageal perforation: A multinational study using the Pittsburgh esophageal perforation severity scoring system

OBJECTIVE

The Pittsburgh group has suggested a perforation severity score (PSS) for better decision making in the management of esophageal perforation. Our study aim was to determine whether the PSS can be used to stratify patients with esophageal perforation into distinct subgroups with differential outcomes in an independent study population.

METHODS

In a retrospective study cases of esophageal perforation were collected (study-period, 1990-2014). The PSS was analyzed using logistic regression as a continuous variable and stratified into low, intermediate, and high score groups.

RESULTS

Data for 288 patients (mean age, 59.9 years) presenting with esophageal perforation (during the period 1990-2014) were abstracted. Etiology was spontaneous (Boerhaave; n = 119), iatrogenic (instrumentation; n = 85), and traumatic perforation (n = 84). Forty-three patients had coexisting esophageal cancer. The mean PSS was 5.82, and was significantly higher in patients with fatal outcome (n = 57; 19.8%; mean PSS, 9.79 vs 4.84; P < .001). Mean PSS was also significantly higher in patients receiving operative management (n = 200; 69%; mean PSS, 6.44 vs 4.40; P < .001). Using the Pittsburgh strata, patients were assigned to low PSS (≤2; n = 63), intermediate PSS (3-5; n = 86), and high PSS (>5; n = 120) groups. Perforation-related morbidity, length of stay, frequency of operative treatment, and mortality increased with increasing PSS strata. Patients with high PSS were 3.37 times more likely to have operative management compared with low PSS.

CONCLUSIONS

The Pittsburgh PSS reliably reflects the seriousness of esophageal perforation and stratifies patients into low-, intermediate-, and high-risk groups with differential morbidity and mortality outcomes.