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We report on a straightforward strategy to fabricate bioactive glycosylated gold nanoparticles via a combination of RAFT polymerization, carbohydrate ligation through reductive amination and thiol–gold self-assembly. This approach is used for the design of gold nanoparticles decorated with the complex sialylated glycan Neu5Ac-α-2-6-Gal, and we demonstrate multivalent and specific recognition between the nanoparticles, lectins and hemagglutinin on the surface of the influenza virus. [ABSTRACT FROM AUTHOR]

We report on transiently responsive protein–polymer conjugates that temporarily change their protein conformation from the soluble to the particle-like state. ‘Grafting-from’ RAFT polymerization of a dioxolane-containing acrylamide with a protein macroCTA is used to design polymer–protein conjugates that self-assemble into nanoparticles at physiological temperature and pH. Acid triggered hydrolysis of the dioxolane units into diol moeities rendered the conjugates fully water soluble irrespective of temperature. [ABSTRACT FROM AUTHOR]

The aim of this study was to apply an untargeted NMR and LC-MS-based metabolomics approach to detect potential differences between an organically and a conventionally produced feed, which caused statistically significant differences in growth, in the response to an immunological challenge and in the gene expression profiles in the small intestine of laying hens. A fractionation procedure was set up to create multiple fractions of the feed, which were subsequently analysed by NMR and UPLC-TOF/MS operating in positive mode. Comparison of the profiles revealed that the most apparent differences came from the isoflavones in the soy as well as a compound with a molecular mass of 441.202 (M + 1)+, which was identified as N,N′-diferuloylputrescine (DFP) and came from the corn. Whether the observed differences in effects are due to the higher levels of isoflavones and DFP is unclear, as is the fact whether the observed differences are typical for organic or conventional produced corn and soy. However, this study shows that this metabolomics approach is suitable for detecting potential differences between products, even in levels of compounds that would have been overlooked with a more targeted approach. As such, the method is suitable for a more systematic study on differences between conventionally and organically produced food. [ABSTRACT FROM AUTHOR]

High levels of dioxins (PCDD/Fs) in pork were discovered in France and the Netherlands at the end of 2008. The contamination was rapidly traced back to a feed stock in the Republic of Ireland (RoI). Burning oil, used for the drying of bakery waste, appeared to be contaminated with PCBs. Consequently, very high levels up to 500 pg TEQ g−1 fat were found in pork. The congener pattern clearly pointed to PCB-oil as a source, but the ratio between the non-dioxin-like indicator PCBs (PCBs 28, 52, 101, 138, 152 and 180) and PCDD/Fs was much lower than observed during the Belgian incident, thereby limiting the suitability of indicator PCBs as a marker for the presence of dioxins and dioxin-like PCBs. This paper describes the tracking and tracing of the incident, the public–private cooperation, the surveillance activities and its results. A major lesson to be learned from this incident is the importance of good private food safety systems. In this incident, it was the private surveillance systems that identified the origin of contamination within 10 days after the first signal of increased dioxin levels in a product. On the other hand, retrospective analyses showed that signals were missed that could have led to an earlier detection of the incident and the source. Above all, the incident would not have occurred when food safety assurance systems had been effectively implemented in the involved feed chain. It is discussed that besides primary responsibility for effective private food safety systems, the competent authorities have to supervise whether the food safety procedures are capable of coping with these kinds of complex food safety issues, while private food companies need to implement the law, and public authorities should supervise and enforce them. Finally, it is discussed whether the health risks derived from consumption of the contaminated batches of meat may have been underestimated during the incident due to the unusually high intake of dioxins. [ABSTRACT FROM AUTHOR]

Sharing and collaboration relating to progress testing already takes place on a national level and allows for quality control and comparisons of the participating institutions. This study explores the possibilities of international sharing of the progress test after correction for cultural bias and translation problems. Three progress tests were reviewed and administered to 3043 Pretoria and 3001 Maastricht medical students. In total, 16% of the items were potentially biased and removed from the test items administered to the Pretoria students (9% due to translation problems; 7% due to cultural differences). Of the three clusters (basic, clinical and social sciences) the social sciences contained most bias (32%), basic sciences least (11%). The differences that were found, comparing the student results of both schools, seem a reflection of the deliberate accentuations that both curricula pursue. The results suggest that the progress test methodology provides a versatile instrument that can be used to assess medical schools across the world. Sharing of test material is a viable strategy and test outcomes are interesting and can be used in international quality control. [ABSTRACT FROM AUTHOR]

Assessment drives the educational behaviour of students and supervisors. Therefore, an assessment programme targeted at specific competencies may be expected to motivate supervisors and students to pay more attention to those competencies. In-training assessment (ITA) is regarded as a feasible method for assessing a broad range of competencies. Before and after the implementation of an ITA programme in an undergraduate Internal Medicine clerkship we surveyed students on the frequency of unobserved and observed supervision, and the quality of feedback as inferred from the seniority of the person providing it. After the implementation of the ITA programme supervision increased, but the difference was not statistically significant. The quality of feedback showed no significant change either. Inter-student variation in supervision and feedback remained invariably high after the implementation of the ITA programme. Whether these results are attributable to the way the programme was implemented or to the way the results were assessed remains to be clarified. [ABSTRACT FROM AUTHOR]

A qualitative spreadsheet model has been developed for ranking feed ingredients on the basis of the potential risk of exceeding existing guidance or maximum levels in the EU for a certain contaminant, and the potential consequence of the presence of this contaminant on the health of animals and/or humans. The approach was based on the general concept of risk, being frequency times consequences of presence of the contaminant. Contamination of compound feeds due to presence of the contaminant in feed ingredients was estimated, per animal category, by: annual volumes of feed ingredients used for feed production, stratified per country of origin; the portion of each ingredient in compound feed formulations used for various animal categories; and the potential contamination of an ingredient per country of origin. The consequences of the contamination were accounted for by two consequence factors, both estimated per animal category: one for the potential impact of the contaminant on the health of the target animal, and one for the impact on human health, related to the possible formation of residues in animal derived food products. The use of the model was demonstrated by its application to the presence of dioxins and dl-PCBs in compound feed for farm animals produced in the Netherlands in 2013 and 2014. Model results include the relative contribution, based on relative ranking scores, of each feed ingredient to the chance of exceeding limits and potential consequences on animal and human health. Feed ingredients ranking highest were palm oil, other fats and oils, dried products like bakery products, sunflower expeller/extracted, maize, and fish meal. The model can be used by risk managers in feed industry and by governmental bodies for supporting decision making on the optimal allocation of resources for control of ingredients for compound feed production for presence of contaminants. [ABSTRACT FROM AUTHOR]