Over-production of exopolysaccharide by Lacticaseibacillus rhamnosus CNCM I-3690 strain cutbacks its beneficial effect on the host.

Most lactobacilli produce extracellular polysaccharides that are considered to contribute to the probiotic effect of many strains. Lacticaseibacillus rhamnosus CNCM I-3690 is an anti-inflammatory strain able to counterbalance gut barrier dysfunction. In this study ten spontaneous variants of CNCM I-3690 with different EPS-production were generated and characterized by their ropy phenotype, the quantification of the secreted EPS and genetic analysis. Amongst them, two were further analysed in vitro and in vivo: an EPS over-producer (7292) and a low-producer derivative of 7292 (7358, with similar EPS levels than the wild type (WT) strain). Our results showed that 7292 does not have anti-inflammatory profile in vitro, and lost the capacity to adhere to the colonic epithelial cells as well as the protective effect on the permeability. Finally, 7292 lost the protective effects of the WT strain in a murine model of gut dysfunction. Notably, strain 7292 was unable to stimulate goblet cell mucus production and colonic IL-10 production, all key features for the beneficial effect of the WT strain. Furthermore, transcriptome analysis of colonic samples from 7292-treated mice showed a down-regulation of anti-inflammatory genes. Altogether, our results point out that the increase of EPS production in CNCM I-3690 impairs its protective effects and highlight the importance of the correct EPS synthesis for the beneficial effects of this strain.

Improving nutritional therapy of persistent critically ill patients by organisational measures: A before and after study.

BACKGROUND & AIMS: Critically ill patients requiring prolonged intensive care (ICU) treatment are at high risk of malnutrition, which latter contributes to worsening outcome. Having observed that despite the presence of a nutrition protocol and dieticians, the patients with persistent critical illness (PCI) had been underfed during their ICU stay and particularly during the first 10 days, the aim was to analyse the impact of the organisational changes that were proposed to prevent the observed malnutrition. METHODS: Before (Period A) and after (Period B) study enrolling critically ill patients consecutively admitted, requiring >10 days of ICU treatment. The intervention consisted in increasing the early morning interactions between dieticians, nurses, and physicians, while modifying the computer visualisation of the dietician proposals. The primary endpoint was a reduction in the cumulative energy balance in period B. The ICU stay was divided in early ICU stay (first 10 days) and late ICU stay (day 11 to day 30). Other variables: protein, glucose, and prealbumin. RESULTS: Altogether, 205 patients (150 and 55 in period A and B respectively) were enrolled in the PCI program. Patient characteristics were similar over both periods except for lower SAPSII score in period B. There was no difference in nutritional pattern in the first 10 days between periods. The cumulate energy balance was less negative from day 11-30 in period B than in A (-884 vs -1566 kcal; p = 0.033). There was a one-day reduction in the median duration of fasting in period B (p < 0.0001). Overall compliance with nutrition protocol improved in period B with an earlier first indirect calorimetry (p = 0.003) and prealbumin measurement (p < 0.001), the latter increasing significantly more during ICU stay. CONCLUSION: Organizational changes that allowed an early identification of patients at nutritional risk, an increased targeted dieticians intervention and a better inter-disciplinary work was associated with a reduction in undue fasting, and significantly improved energy balances.

Transferability of microsatellite primers developed for stingless bees to four other species of the genus Melipona.

Microsatellite markers are a useful tool for ecological monitoring of natural and managed populations. A technical limitation is the necessity for investment in the development of primers. Heterologous primers can provide an alternative to searching for new loci. In bees, these markers have been used in populational and intracolonial genetic analyses. The genus Melipona has the largest number of species among bee genera, about 70, occurring throughout the Neotropical region. However, only five species of the genus Melipona have specific microsatellite markers. Given the great diversity of this genus, this number is not representative. We analyzed the transferability of 49 microsatellite loci to four other species of the genus Melipona (M. scutellaris, M. mondury, M. mandacaia, and M. quadrifasciata). Four individuals of each species, from different localities, were used in amplification tests. Primer pairs described for five Melipona species and for Trigona carbonaria were tested. Among the 49 loci, 22 gave amplification products for all four species, while three gave nonspecific bands and five showed no amplification products. The remaining loci varied in the pattern of amplification, according to the species examined. The number of alleles ranged from 1 to 6. The results demonstrate the possibility of using these heterologous markers in other Melipona species, increasing the number of loci that can be analyzed and contributing to further genetic analyses of intra- and intercolonial structure, which is required for conservation measure planning, genetic improvement and resolution of taxonomic problems.