SciCombinator

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Concept: Streptococcus thermophilus

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BACKGROUND AND AIMS:: Several studies have suggested that probiotics (proB) and/or prebiotics (preB) could reduce the burden of infection in infants and toddlers. We aimed to determine whether follow-up formula supplemented with proB and preB could reduce the risk of acute otitis media (AOM). METHODS:: In this double-blind, placebo-controlled trial from November 2007 to April 2009, 37 pediatricians in France enrolled children 7 to 13 months old with high risk of AOM who were randomly assigned to receive follow-up formula supplemented with proB (Streptococcus thermophilus NCC 2496, Streptococcus salivarius DSM 13084, Lactobacillus rhamnosus LPR CGMCC 1.3724) and preB (Raftilose/Raftiline) or follow-up formula alone (placebo). During 12 months, the 2 groups were compared for number of AOM episodes diagnosed (primary outcome) and secondary outcomes by the Poisson model (incidence rate ratio [IRR]) or logistic regression (odds ratio [OR]; and 95% confidence interval [95% CI]) after adjustment on covariates of interest. RESULTS:: We enrolled 224 children (112 in each group). All children were vaccinated (4 doses) with the 7 valent pneumococcal conjugate vaccine; demographic characteristics were similar in the 2 groups. In total, 486 AOM episodes were reported, 249 and 237 in the treatment and control groups, respectively. The treatment and control groups did not differ in incidence of AOM (IRR 1.0, 95% CI 0.8-1.2), lower respiratory tract infections (IRR 0.9, 0.7-1.2) or number of antibiotic treatment courses (IRR =1.0, (95%CI 0.8-1.2). Treatment was not associated with recurrent AOM (OR 1.0, 95% CI 0.5-1.7). Regarding gastrointestinal disorders, both formulas were well tolerated. CONCLUSION:: The proB and preB included in follow-up formula given to chidren at 7 to 13 months of age did not reduce the risk of AOM, recurrent AOM, antibiotic use or lower respiratory tract infections at 1 year.

Concepts: Streptococcus pneumoniae, Infection, Respiratory system, Upper respiratory tract, Antibiotic, Otitis media, Probiotic, Streptococcus thermophilus

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Background: Streptococcus salivarius K12 has been shown to inhibit the growth of Streptococcus pyogenes due to bacteriocins release. Because of its ability to colonize the oral cavity, we have tested the strain K12 for its efficacy in preventing streptococcal pharyngitis and/or tonsillitis in adults. Methods: Forty adults with a diagnosis of recurrent oral streptococcal pharyngitis were enrolled in the study. Twenty of these subjects took for 90 days a tablet containing Streptococcus salivarius K12 (Bactoblis®). The other 20 subjects served as untreated controls. A 6-month follow-up was included to evaluate any persistent protective role. Results: The 20 adults who completed the 90-day course of Bactoblis® showed a reduction in their episodes of streptococcal pharyngeal infection (about 80%). The 90 days treatment was also associated with an approximately 60% reduction in the incidence of reported pharyngitis in the 6-month period following use of the product. The product was well tolerated by the subjects with no treatment-related side effects or drop-outs reported. Conclusion: Prophylactic administration of Streptococcus salivarius K12 to adults having a history of recurrent oral streptococcal pathology reduced the number of episodes of streptococcal pharyngeal infections and/or tonsillitis.

Concepts: Streptococcus pyogenes, Rheumatic fever, Streptococcus, Gram positive bacteria, Streptococcaceae, Group A streptococcal infection, Streptococcus thermophilus, Streptococcus salivarius

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The focus of this study was to coculture probiotic Bacillus spp. with dairy starter cultures namely, Streptococcus thermophilus and Lactobacillus bulgaricus for enhanced nutritional properties of soy-curd. Subsequently, rheological, sensory, and antioxidant properties of soy-curd along with mineral as well as fatty acid composition were analyzed. Data revealed an increase in the cell viability of probiotic Bacillus spp. on coculturing rather than as mono-culture. Proximate analysis showed higher nutritional value along with increased trace elements. UFA/SFA ratio, rheology, and sensory properties of probiotic soy-curd were in the acceptable range. Probiotic soy-curd showed higher antioxidant activity as measured by the ability to scavenge free radicals. No significant difference in the overall quality within the probiotic products was observed. However, B. flexus MCC2427 cocultured product displayed slightly better attributes than other samples. In general, the results suggest that soy-curd can be a suitable carrier for probiotic Bacillus spp. and the enhanced nutritional and antioxidant properties could be of additional advantage to combat malnutrition problem.

Concepts: Bacteria, Gut flora, Nutrition, Fatty acid, Microbiology, Antioxidant, Probiotic, Streptococcus thermophilus

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Probiotics have immunomodulatory effects. However, little is known about the potential benefit of probiotics on the inflammation subsequent to strenuous exercise. In a double-blind, randomized, placebo controlled, crossover design separated by a 21-day washout, 15 healthy resistance-trained men ingested an encapsulated probiotic Streptococcus (S.) thermophilus FP4 and Bifidobacterium (B.) breve BR03 at 5 bn live cells (AFU) concentration each, or a placebo, daily for 3 weeks prior to muscle-damaging exercise (ClinicalTrials.gov NCT02520583). Isometric strength, muscle soreness, range of motion and girth, and blood interleukin-6 (IL-6) and creatine kinase (CK) concentrations were measured from pre- to 72 h post-exercise. Statistical analysis was via mixed models and magnitude-based inference to the standardized difference. Probiotic supplementation resulted in an overall decrease in circulating IL-6, which was sustained to 48 h post-exercise. In addition, probiotic supplementation likely enhanced isometric average peak torque production at 24 to 72 h into the recovery period following exercise (probiotic-placebo point effect ±90% CI: 24 h, 11% ± 7%; 48 h, 12% ± 18%; 72 h, 8% ± 8%). Probiotics also likely moderately increased resting arm angle at 24 h (2.4% ± 2.0%) and 48 h (1.9% ± 1.9%) following exercise, but effects on soreness and flexed arm angle and CK were unclear. These data suggest that dietary supplementation with probiotic strains S. thermophilus FP4 and B. breve BR03 attenuates performance decrements and muscle tension in the days following muscle-damaging exercise.

Concepts: Clinical trial, Gut flora, Streptococcus, Muscle, Probiotic, Streptococcaceae, Streptococcus thermophilus, Stretching

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The lactic acid bacterium Lactobacillus rhamnosus GG is the most studied probiotic bacterium with proven health benefits upon oral intake, including the alleviation of diarrhea. The mission of the Yoba for Life foundation is to provide impoverished communities in Africa increased access to Lactobacillus rhamnosus GG under the name Lactobacillus rhamnosus yoba 2012, world’s first generic probiotic strain. We have been able to overcome the strain’s limitations to grow in food matrices like milk, by formulating a dried starter consortium with Streptococcus thermophilus that enables the propagation of both strains in milk and other food matrices. The affordable seed culture is used by people in resource-poor communities.

Concepts: Bacteria, Microbiology, Streptococcus, Lactic acid, Probiotic, Lactobacillus, Streptococcus thermophilus, Lactobacillus rhamnosus

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To expand the repertoire of Cas9s available for genome targeting, we present a new in vitro method for the simultaneous examination of guide RNA and protospacer adjacent motif (PAM) requirements. The method relies on the in vitro cleavage of plasmid libraries containing a randomized PAM as a function of Cas9-guide RNA complex concentration. Using this method, we accurately reproduce the canonical PAM preferences for Streptococcus pyogenes, Streptococcus thermophilus CRISPR3 (Sth3), and CRISPR1 (Sth1). Additionally, PAM and sgRNA solutions for a novel Cas9 protein from Brevibacillus laterosporus are provided by the assay and are demonstrated to support functional activity in vitro and in plants.

Concepts: DNA, Gene, Bacteria, Genome, RNA, Streptococcus pyogenes, Streptococcus, Streptococcus thermophilus

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Proton-dependent oligopeptide transporters (POTs) are important for uptake of dietary di- and tripeptides in many organisms, and in humans are also involved in drug absorption. These transporters accept a wide range of substrates, but the structural basis for how different peptide side chains are accommodated has so far remained obscure. Twenty-eight peptides were screened for binding to PepTSt from Streptococcus thermophilus, and structures were determined of PepTSt in complex with four physicochemically diverse dipeptides, which bind with millimolar affinity: Ala-Leu, Phe-Ala, Ala-Gln, and Asp-Glu. The structures show that PepTSt can adapt to different peptide side chains through movement of binding site residues and water molecules, and that a good fit can be further aided by adjustment of the position of the peptide itself. Finally, structures were also determined in complex with adventitiously bound HEPES, polyethylene glycol, and phosphate molecules, which further underline the adaptability of the binding site.

Concepts: DNA, Protein, Human, Amino acid, Water, System, Peptides, Streptococcus thermophilus

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CRISPR-Cas adaptive immune systems in prokaryotes boast a diversity of protein families and mechanisms of action, where most systems rely on protospacer-adjacent motifs (PAMs) for DNA target recognition. Here, we developed an in vivo, positive, and tunable screen termed PAM-SCANR (PAM screen achieved by NOT-gate repression) to elucidate functional PAMs as well as an interactive visualization scheme termed the PAM wheel to convey individual PAM sequences and their activities. PAM-SCANR and the PAM wheel identified known functional PAMs while revealing complex sequence-activity landscapes for the Bacillus halodurans I-C (Cascade), Escherichia coli I-E (Cascade), Streptococcus thermophilus II-A CRISPR1 (Cas9), and Francisella novicida V-A (Cpf1) systems. The PAM wheel was also readily applicable to existing high-throughput screens and garnered insights into SpyCas9 and SauCas9 PAM diversity. These tools offer powerful means of elucidating and visualizing functional PAMs toward accelerating our ability to understand and exploit the multitude of CRISPR-Cas systems in nature.

Concepts: DNA, Protein, Bacteria, Gut flora, Evolution, Escherichia coli, Adaptive immune system, Streptococcus thermophilus

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Secretory otitis media (SOM) remains a common disease among children. Although its cause is not yet perfectly established, the pathology, often a sequel of acute otitis media (AOM), is mainly characterized by persistent fluid in the middle ear cavity. Twenty-two children with a diagnosis of SOM were treated daily for 90 days with an oral formulation containing the oral probiotic Streptococcus salivarius K12 (Bactoblis(®)). After treatment, the children were evaluated for AOM episodes and subjected to tone audiometry, tympanometry, endonasal endoscopy, otoscopy, and tonsillar examination. Subject compliance and probiotic tolerability and side effects have also been evaluated. Our results indicate a good safety profile, a substantial reduction of AOM episodes, and a positive outcome from the treatment for all of the clinical outcomes tested. We conclude that strain K12 may have a role in reducing the occurrence and/or severity of SOM in children. From our perspective, this study constitutes a starting point toward the organization of a more extensive placebo-controlled study aimed at critically appraising our preliminary observations.

Concepts: Streptococcus pneumoniae, Middle ear, Eustachian tube, Otitis media, Otitis externa, Streptococcus thermophilus, Otoscope, Streptococcus salivarius

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To investigate the effects of four strains, generally used in clinic, including Bifidobacterium longum, Lactobacillus acidophilus, Streptococcus thermophilus and Enterococcus faecalis, and their related products on human colonic smooth muscle in vitro.

Concepts: Streptococcus, Probiotic, Enterococcus, Lactobacillus acidophilus, Streptococcus thermophilus, Firmicutes, Enterococcus faecalis, Lactobacillales