Monitoring immune modulation by nutrition in the general population: identifying and substantiating effects on human health

Optimal functioning of the immune system is crucial to human health, and nutrition is one of the major exogenous factors modulating different aspects of immune function. Currently, no single marker is available to predict the effect of a dietary intervention on different aspects of immune function. To provide further guidance on the assessment and interpretation of the modulation of immune functions due to nutrition in the general population, International Life Sciences Institute Europe commissioned a group of experts from academia, government and the food industry to prepare a guidance document. A draft of this paper was refined at a workshop involving additional experts. First, the expert group defined criteria to evaluate the usefulness of immune function markers. Over seventy-five markers were scored within the context of three distinct immune system functions: defence against pathogens; avoidance or mitigation of allergy; control of low-grade (metabolic) inflammation. The most useful markers were subsequently classified depending on whether they by themselves signify clinical relevance and/or involvement of immune function. Next, five theoretical scenarios were drafted describing potential changes in the values of markers compared with a relevant reference range. Finally, all elements were combined, providing a framework to aid the design and interpretation of studies assessing the effects of nutrition on immune function. This stepwise approach offers a clear rationale for selecting markers for future trials and provides a framework for the interpretation of outcomes. A similar stepwise approach may also be useful to rationalise the selection and interpretation of markers for other physiological processes critical to the maintenance of health and well-bein

A novel non-digestible, carrot-derived polysaccharide (cRG-I) selectively modulates the human gut microbiota while promoting gut barrier integrity : an integrated in vitro approach

Modulation of the gut microbiome as a means to improve human health has recently gained increasing interest. In this study, it was investigated whether cRG-I, a carrot-derived pectic polysaccharide, enriched in rhamnogalacturonan-I (RG-I) classifies as a potential prebiotic ingredient using novel in vitro models. First, digestion methods involving alpha-amylase/brush border enzymes demonstrated the non-digestibility of cRG-I by host-derived enzymes versus digestible (starch/maltose) and non-digestible controls (inulin). Then, a recently developed short-term (48 h) colonic incubation strategy was applied and revealed that cRG-I fermentation increased levels of health-promoting short-chain fatty acids (SCFA; mainly acetate and propionate) and lactate comparable but not identical to the reference prebiotic inulin. Upon upgrading this fermentation model by inclusion of a simulated mucosal environment while applying quantitative 16S-targeted Illumina sequencing, cRG-I was additionally shown to specifically stimulate operational taxonomic units (OTUs) related to health-associated species such asBifidobacterium longum,Bifidobacterium adolescentis,Bacteroides dorei,Bacteroides ovatus,Roseburia hominis,Faecalibacterium prausnitzii, andEubacterium hallii. Finally, in a novel model to assess host-microbe interactions (Caco-2/peripheral blood mononuclear cells (PBMC) co-culture) fermented cRG-I increased barrier integrity while decreasing markers for inflammation. In conclusion, by using novel in vitro models, cRG-I was identified as a promising prebiotic candidate to proceed to clinical studies

Structure dependent fermentation kinetics of dietary carrot rhamnogalacturonan-I in an in vitro gut model

Plant derived dietary polysaccharides are important for gut health and have the potential to modulate the gut microbial community. Dietary rhamnogalacturonan-I obtained by enzymatic treatment of carrot pomace has shown prebiotic properties. In the present study, fermentability of carrot rhamnogalacturonan-I (cRG-I) by faecal microbiota of four donors was studied in an adapted M-SHIME® intestinal model. Despite its complex structure, cRG-I was degraded rapidly in the proximal colon compartment and fermentation became quicker and more complete during three weeks of repeated supplementation. Tracking the change in the molecular weight distribution pattern of cRG-I during the supplementation showed two main donor-dependent gut microbial fermentation strategies designated as either the general or preferential pathway. In the general fermentation pathway, different cRG-I structures were hydrolysed concomitantly, while in the preferential pathway discrete structures were sequentially fermented in a selective manner. Especially arabinan sidechains were utilized before the RG-I backbone, which correlated with an increase in Bifidobacterium longum absolute abundance over the three weeks period. MALDI-TOF MS confirmed that arabinan-, galactan- and arabinogalactan-sidechains were first to be released and degraded. Donor specific production of all SCFA increased over time with a general trend of higher levels of acetate and propionate than butyrate. Strikingly, although the host's baseline gut microbiota composition led to distinct cRG-I hydrolysis routes, the final RG-I consumption was almost complete for both routes, leading to similar metabolic profiles at the end of the three weeks treatment period

The Memrise Prize, an International Research Competition: A Pragmatic Trial to Compare Methods for Learning Foreign Language Vocabulary

How well do learning techniques work in the real world, and what happens when several techniques are combined? We conducted a competition in which international research teams developed methods to maximize the number of correct translations that learners could acquire in 1 hr and successfully recall 1 week later. Teams initially tested their method for learning 80 Lithuanian–English words pairs against a standardized control method. Five shortlisted methods and the control condition were then compared on a common online platform, using Lakota–English pairs, with retention data collected from over 3,803 users of an online learning tool. The winning entry, which combined a visual mnemonic technique with retrieval practice and an adaptive algorithm for introducing new words, achieved an average of 27.23, 95% CI [26.08, 28.38] out of 80 word pairs recalled. This work highlights the contribution that competitions can play in addressing practical questions about human learning and memory

Crowdsourcing hypothesis tests: Making transparent how design choices shape research results

To what extent are research results influenced by subjective decisions that scientists make as they design studies? Fifteen research teams independently designed studies to answer fiveoriginal research questions related to moral judgments, negotiations, and implicit cognition. Participants from two separate large samples (total N > 15,000) were then randomly assigned to complete one version of each study. Effect sizes varied dramatically across different sets of materials designed to test the same hypothesis: materials from different teams renderedstatistically significant effects in opposite directions for four out of five hypotheses, with the narrowest range in estimates being d = -0.37 to +0.26. Meta-analysis and a Bayesian perspective on the results revealed overall support for two hypotheses, and a lack of support for three hypotheses. Overall, practically none of the variability in effect sizes was attributable to the skill of the research team in designing materials, while considerable variability was attributable to the hypothesis being tested. In a forecasting survey, predictions of other scientists were significantly correlated with study results, both across and within hypotheses. Crowdsourced testing of research hypotheses helps reveal the true consistency of empirical support for a scientific claim.</div

Organisational Culture and Employability of Older Workers; the Influence of the nature of work Analyzing the moderating effect of the nature of work on the relationship between organisational culture and perceived employability.

Summary Master Thesis – Ruud Albers, s1027163 Due to the growing number of 50+ employees within organisations and consequent labor shortages, a need has risen to successfully manage the employability of the older employee. This study focusses on the relationship between the organisational culture and the employability level of older employees in order to provide findings on how to improve the employability of older employees. Organisational culture within this study was measured by the three constructs: ‘Equality of Opportunity’, ‘Image of Age’, and ‘Open & Target-group Specific Communication’. Based on the decreasing mental and physical capacity of the human body due to age, combined with the negative stereotypes towards older employees, the moderating effect of the nature of work was tested to see if the relationship between organisational culture and employability is significantly different for employees performing office work than for employees doing physical work. This study collected quantitative data from a sample of 235 respondents by the usage of a survey. The results showed no significant relationship between organisational culture and the employability level of older employees. In addition, the nature of work does not moderate this relationship. Nevertheless, the results have shown that perceived health has a positively influence on employability, while physical work has a negative influence on employability. This study provides practical recommendations for managers and organisations to improve the accessibility to a healthier employee lifestyle, and to decrease the percentage of the time an older employee spends doing physical work