Functional properties of Lactobacillus plantarum strains: A multivariate screening study

Thirty-two Lactobacillus plantarum strains isolated from different sources were genetically characterized at subspecies level with recA gene based multiplex PCR and pulsed-field electrophoresis. All the strains were tested in vitro for functional properties (ability to form biofilms, agglutination of yeast cells, bile salt hydrolase activity, β-galactosidase activity, surface hydrophobicity, resistance to lysozyme, gastric juice and bile salts), for antimicrobial activity and for antibiotic resistance. The presence of bsh and msa genes and of the pln bacteriocin loci were also evaluated. Hierarchical cluster analysis was used to identify eight different plantaritypes sharing similar patterns of pln loci. A global functional score was calculated by transforming values for continuous in vitro functional properties in an ordinal scale by cluster analysis, while a nominal scale was used for the other properties. Multidimensional scaling was used to evaluate the similarity in functional properties among the isolates and to evaluate the relationships between source of isolation and functional properties. Nine strains showed the best in vitro functional potential and a significant relationship was found between source of isolation and functional score. This study confirmed a high heterogeneity in functional properties among L. plantarum strains and provides insight for optimal screening strategie

Polymorphisms in stress response genes in Lactobacillus plantarum: implications for classification and heat stress response

The polymorphism of 5 stress response genes (hrcA, ctsR, clpP, ftsH, dnaK) in 32 Lactobacillus plantarum strains was evaluated by multilocus restriction typing (MLRT) and by sequence analysis of ctsR, hrcA and clpP genes. Both these approaches allowed the discrimination of the subspecies L. plantarum ssp. plantarum and L. plantarum ssp. argentoratensis. HrcA sequence analysis also allowed discrimination at the species and subspecies level of several species of lactic acid bacteria, thus confirming that it can be used as a valuable taxonomic marker. No significant relationship was found between stress response gene polymorphism and resistance to heat treatments. The effect of temperature on growth kinetics and the protein expression were investigated for selected strains carrying different mutations in hrcA. L. plantarum ssp. argentoratensis NCIMB12120 and L. plantarum ssp. plantarum DPC2159, both of which had mutations in domains of HrcA which are important for the repressor functionality, had a reduced growth rate at all temperatures tested (25, 30, 37, 40, and 42 °C) compared to L. plantarum WCFS1. In L. plantarum DPC2159, protein expression upon temperature shifts from 25 to 40 °C or growth at 40 °C was altered compared to L. plantarum WCFS1, but further study is needed to unequivocally confirm the relationship with mutations in hrcA

Distribution of Plasmodium falciparum gametocytes and malaria-attributable fraction of fever episodes along an altitudinal transect in Western Cameroon

Background: Highland areas are hypoendemic zones of malaria and are therefore prone to epidemics, due to lack of protective immunity. So far, Cameroon has not succeeded in implementing a convenient and effective method to detect, prevent and forecast malaria epidemic in these peculiar zones. This monitoring and evaluation study aims to assess the operational feasibility of using the human malaria infectious reservoir (HMIR) and the malaria-attributable fraction of fever episodes (MAFE) as indicators, in designing a malaria epidemic early warning system (MEWS). Methods: Longitudinal parasitological surveys were conducted in sentinel health centres installed in three localities, located along an altitudinal transect in Western Cameroon: Santchou (750 m), Dschang (1,400 m) and Djuttitsa (1,965 m). The syndromes of outpatients with malaria-like complaints were recorded and their blood samples examined. The HMIR and the MAFE were estimated and their spatial-temporal variations described. Results: The prevalence of asexual Plasmodium infection in outpatients decreased with increasing altitude; meanwhile the HMIR remained fairly constant, indicating that scarcity of malaria disease in highlands is likely due to absence of vectors and not parasites. In lowland, children carried the heaviest malaria burden in the form of febrile episodes, and asexual parasites decreased with age, after an initial peak in the 0-5 year's age group; however, they were similar for all age groups in highland. The HMIR did not show any variation with age in the plain; but some discrepancies were observed in the highland with extreme age groups, and migration of populations between lowland and highland was suspected to be the cause. Plasmodium infection was perennial in the lowland and seasonal uphill, with malaria disease occurring here mostly during the short dry season. The MAFE was high and did not change with altitude. Conclusion: It is obvious that a malaria outbreak will cause the sudden rise of HMIR and MAFE in highland, prior to the malaria season; the discrepancy with lowland would then help detecting an incipient malaria epidemic. It is recommended that in designing the MEWS, the National Malaria Control Programme should include these parameters and put special emphasis on: altitude, age groups and seasons

(S)-[6]-Gingerol inhibits TGF-b-stimulated biglycan synthesis but not glycosaminoglycan hyperelongation in human vascular smooth muscle cells

Objectives (S)-[6]-Gingerol is under investigation for a variety of therapeutic uses. Transforming growth factor (TGF)-b stimulates proteoglycan synthesis, leading to increased binding of low-density lipoproteins, which is the initiating step in atherosclerosis.We evaluated the effects of (S)-[6]-gingerol on these TGFb- mediated proteoglycan changes to explore its potential as an anti-atherosclerotic agent. Methods Purified (S)-[6]-gingerol was assessed for its effects on proteoglycan synthesis by [35S]-sulfate incorporation into glycosaminoglycan chains and [35S]-Met/Cys incorporation into proteoglycans and total proteins in human vascular smooth muscle cells. Biglycan level was assessed by real-time quantitative polymerase chain reactions and the effects of (S)-[6]-gingerol on TGF-b signalling by assessment of the phosphorylation of Smads and Akt by western blotting. Key findings (S)-[6]-Gingerol concentration-dependently inhibited TGF-bstimulated proteoglycan core protein synthesis, and this was not secondary to inhibition of total protein synthesis. (S)-[6]-Gingerol inhibited biglycan mRNA expression. (S)-[6]-Gingerol did not inhibit TGF-b-stimulated glycosaminoglycan hyperelongation or phosphorylation of Smad 2, in either the carboxy terminal or linker region, or Akt phosphorylation. Conclusions The activity of (S)-[6]-gingerol to inhibit TGF-b-stimulated biglycan synthesis suggests a potential role for ginger in the prevention of atherosclerosis or other lipid-binding diseases. The signalling studies indicate a novel site of action of (S)-[6]-gingerol in inhibiting TGF-b responses

Effects of transoral gastroplasty on glucose homeostasis in obese subjects

Transoral gastroplasty (TOGA) is a safe and less invasive procedure than traditional bariatric surgery. We studied the effects of TOGA on the risk of progression from prediabetes to overt type 2 diabetes mellitus (T2DM) or on regression from diabetes or prediabetes to a lower risk category

Effect of single anastomosis duodenal-ileal bypass with sleeve gastrectomy on glucose tolerance test: comparison with other bariatric procedures

Background: No data have been reported regarding the risk of hyperinsulinemic response and reactive hypoglycemia after single anastomosis duodenal-ileal bypass with sleeve gastrectomy (SADI-S). Furthermore, comparative studies with other bariatric procedures are lacking. Objectives: To compare response to oral glucose tolerance test (OGTT) in patients who underwent SADI-S, Roux-en-Y gastric bypass (RYGB), sleeve gastrectomy (SG), and biliopancreatic diversion (BPD). Setting: Fondazione Policlinico Universitario \u201cA. Gemelli\u201d IRCCS, Universit\ue0 Cattolica del Sacro Cuore, Rome. Methods: Consenting, nondiabetic patients matched for age, sex, and preoperative body mass index, who underwent SADI-S, RYGB, SG, and BPD, were recruited. A 75 g OGTT was performed pre and postoperatively. Plasma insulin and glucose (pGlu\u2013mg/dL) were measured at baseline, and at +30, +60, +90, +120, +150, and +180 minutes. Severe hypoglycemia was defined as pGlu concentration <55 mg/dL. Results: Thirty-five patients were recruited: 9 SADI-S, 11 RYGB, 7 SG, and 8 BPD. Comparing preoperative and postoperative responses to OGTT, all procedures improved the glycemic control with better early results after SADI-S and BPD compared with RYGB and SG. No patients showed severe hypoglycemia. Significantly more patients who underwent RYGB and SG showed asymptomatic pGlu <70 mg/dL during OGTT compared with SADI-S and BPD (63.6% and 57.1% vs 22.2% and 12.5%, respectively, P <.05). Conclusions: Similar to BPD, SADI-S seems to be associated to insulin sensitivity and glucose homeostasis improvement, together with a reduced risk of hyperinsulinemia and, consequently, to hypoglycemia, often associated with RYGB and SG