36 research outputs found
Antioxidant vitamins and prebiotic FOS and XOS differentially shift microbiota composition and function and improve intestinal epithelial barrier in vitro
Human gut microbiota (HGM) play a significant role in health and disease. Dietary components, including fiber, fat, proteins and micronutrients, can modulate HGM. Much research has been performed on conventional prebiotics such as fructooligosaccharides (FOS) and galactooligosaccharides (GOS), however, novel prebiotics or micronutrients still require further validation. We assessed the effect of FOS, xylooligosaccharides (XOS) and a mixture of an antioxidant vitamin blend (AOB) on gut microbiota composition and activity, and intestinal barrier in vitro. We used batch fermentations and tested the short-term effect of different products on microbial activity in six donors. Next, fecal inocula from two donors were used to inoculate the simulator of the human microbial ecosystem (SHIME) and after long-term exposure of FOS, XOS and AOB, microbial activity (short- and branched-chain fatty acids and lactate) and HGM composition were evaluated. Finally, in vitro assessment of intestinal barrier was performed in a Transwell setup of differentiated Caco-2 and HT29-MTX-E12 cells exposed to fermentation supernatants. Despite some donor-dependent differences, all three tested products showed beneficial modulatory effects on microbial activity represented by an increase in lactate and SCFA levels (acetate, butyrate and to a lesser extent also propionate), while decreasing proteolytic markers. Bifidogenic effect of XOS was consistent, while AOB supplementation appears to exert a specific impact on reducing F. nucleatum and increasing butyrate-producing B. wexlerae. Functional and compositional microbial changes were translated to an in vitro host response by increases of the intestinal barrier integrity by all the products and a decrease of the redox potential by AOB supplementation
Non-consensual sex and help-seeking behavior among PrEP users in Belgium : findings from an online survey
Absorption strengths in the far-IR spectrum of shallow donors and acceptors in germanium
Dynamical magnetostructural properties of Anabaena ferredoxin
A mixed quantum/classical investigation of the dynamical magnetostructural properties, that is, “magnetodynamics,” of oxidized Anabaena PCC7119 ferredoxin is carried out at room temperature in two distinct conformational states. This protein hosts a [2Fe–2S] cluster in which two iron centers are antiferromagnetically coupled to an overall low-spin electronic ground state that has a genuine multireference character. To study the magnetodynamics of this prosthetic group, an approximate spin projection method is formulated in the framework of density functional theory that allows for multideterminant ab initio molecular dynamics simulations to be carried out efficiently. By using this scheme, the influence of both thermal fluctuations and conformational motion on the structure of the [2Fe–2S] cluster and on the dynamics of the antiferromagnetic coupling constant, J(t), has been investigated. In addition to demonstrating how sensitively the shape of the [2Fe–2S] core itself is affected by hydrogen bonding, the analyses reveal a complex dynamical coupling of J to both local vibrations and large-amplitude motion. It is shown that this interplay can be understood in terms of specific vibrational modes and distinct hydrogen-bonding patterns between the iron–sulfur cluster and the protein backbone, respectively. This implies going beyond the Goodenough–Kanamori rules for angular magnetostructural correlations of oxidized iron–sulfur prosthetic groups
Antifungal Spectrum, In Vivo Efficacy, and Structure–Activity Relationship of Ilicicolin H
Giving Feedback on Peers’ Concept Maps in an Inquiry Learning Context: The Effect of Providing Assessment Criteria
“Now you know what you’re doing right and wrong!” Peer feedback quality in synchronous peer assessment in secondary education
Site-directed mutagenesis of selected residues at the active site of aryl-alcohol oxidase, an H 2
Catering for diversity in the digital age: Reconsidering equity in assessment practices
While the affordance of the digital age certainly enable more diver e students to access higher education, higher education assessment is often under-Âpinned by notion of equality rather than equity. Drawing together key literature and data from interviews with 53 first year undergraduate student from low socioÂeconomic status background, this chapter identifies three potential causes of assessment inequity which appear to persist into the digital age: student assessment
elf-efficacy, prior preparation. and external pressures. It then identifies how the affordance of modern technology can be used to help combat these challenges