From PLoS website: In general, dietary antigens are tolerated by the gut associated immune system. Impairment of this so-called oral tolerance is a serious health risk. We have previously shown that activation of the ligand-dependent transcription factor aryl hydrocarbon receptor (AhR) by the environmental pollutant 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) affects both oral tolerance and food allergy. In this study, we determine whether a common plant-derived, dietary AhR-ligand modulates oral tolerance as well. We therefore fed mice with indole-3-carbinole (I3C), an AhR ligand that is abundant in cruciferous plants. We show that several I3C metabolites were detectable in the serum after feeding, including the high-affinity ligand 3,3´-diindolylmethane (DIM). I3C feeding robustly induced the AhR-target gene CYP4501A1 in the intestine; I3C feeding also induced the aldh1 gene, whose product catalyzes the formation of retinoic acid (RA), an inducer of regulatory T cells. We then measured parameters indicating oral tolerance and severity of peanut-induced food allergy. In contrast to the tolerance-breaking effect of TCDD, feeding mice with chow containing 2 g/kg I3C lowered the serum anti-ovalbumin IgG1 response in an experimental oral tolerance protocol. Moreover, I3C feeding attenuated symptoms of peanut allergy. In conclusion, the dietary compound I3C can positively influence a vital immune function of the gut.
MULTIFILE
Human exposure to polybrominated diphenyl ethers (PBDEs) can occur via ingestion of indoor dust, inhalation of PBDE-contaminated air and dust-bound PBDEs. However, few studies have examined the pulmonary toxicity of particle-bound PBDEs, mainly due to the lack of an appropriate particle-cell exposure system. In this study we developed an in vitro exposure system capable of generating particle-bound PBDEs mimicking dusts containing PBDE congeners (PBDEs 35, 47 and 99) and delivering them directly onto lung cells grown at an air–liquid interface (ALI). The silica particles and particles-coated with PBDEs ranged in diameter from 4.3 to 4.5 μm and were delivered to cells with no apparent aggregation. This experimental set up demonstrated high reproducibility and sensitivity for dosing control and distribution of particles. All exposure of cells to PBDE-bound particles significantly decreased cell viability and induced reactive oxygen species generation in A549 and NCI-H358 cells. In male Sprague-Dawley rats exposed via intratracheal insufflation (0.6 mg/rat), particle-bound PBDE exposures induced inflammatory responses with increased recruitment of neutrophils to the lungs compared to sham-exposed rats. The present study clearly indicates the potential of our exposure system for studying the toxicity of particle-bound compounds.Abstract of the paper published by Elsevier. The whole paper can be obtained via: http://www.sciencedirect.com/science/article/pii/S0300483X14000067#
MULTIFILE
BackgroundIn 2015, Amsterdam became part of the WHO Age Friendly City community, thereby accepting the responsibility to work towards a more age friendly Amsterdam. To study senior citizens’ needs and wishes concerning the age friendliness of their neighbourhood, the municipality asked the Amsterdam University of Applied Science to set up two pilot projects in two neighbourhoods. Aim was to 1) gain insight in seniors’ views and wishes regarding an age friendly city, and 2) reflect on the experiences with working with senior co-researchers. MethodologyThe study followed a Participatory Action Research approach with research teams consisting of seniors as co-researchers and professional researchers. We chose two neighbourhoods with distinct characteristics: the Indische Buurt which is centrally located, vibrant, multicultural, and strongly gentrifying, and Buitenveldert, a suburban and spacious neighbourhood, with less facilities and a dominance of well-to-do senior citizens. In both areas, we recruited senior co-researchers to form the research teams. They generally lived in, or close to, the pilot neighbourhood, and varied in age and ethnical background. The aim was to put the co-researchers in the lead during the entire research process. However, it differed between the neighbourhoods which type of researcher was in the lead. As a team, they formulated the main research question, constructed a topic list for interviews with older citizens, convened the interviews, analysed the data, wrote the report, and presented the results. During the entire process, they were supported by professional researchers.Both research teams interviewed 40 senior citizens, who were recruited through the co-researchers’ networks, professional care organisations, neighbourhood communities, and local media. We intended to gather a sample representative for the neighbourhood population. In the Indische Buurt, this proved to be difficult, since the relatively large Turkish and Moroccan communities were difficult to get into contact with, and it was hard to find co-researchers from those communities who could have provided a way in. Process and outcomesWe will share some of the results, but we will mainly reflect on the research process. ProcessRegarding the process, we found some differences between the two neighbourhoods. In the Indische Buurt, it took much effort to find co-researchers, since the seniors we encountered said to be too busy with other neighbourhood activities. We did recruit a small group of four co-researchers of different ethnical background, but sadly lacking Turkish and Moroccan seniors. They started with a very limited research experience and experienced ownership, which greatly increased during the process. At the finalisation of the project, the group ceased to be, but the outcomes were followed up by existing groups and organisations in the neighbourhood.In Buitenveldert, a large group of co-researchers was recruited in no-time, bearing more resemblance to an action group than a research group. They were generally highly educated and some already had research experience. The group proved to be pro-active, had a strong feeling of ownership, and worked in constant collaboration with the ‘professional’ researchers, respecting each other’s knowledge and skills. At the finalisation of the project, the group remained active as partner of the local government. OutcomesConcerning the content of the outcomes, we found some expected differences and unexpected similarities. For instance, we expected to find different outcomes concerning housing and facilities between the neighbourhoods. Indeed, in Buitenveldert, housing was already age friendly whereas facilities were scarce and geographically far apart. Yet, in the Indische Buurt, housing was poorly equipped for physically impaired seniors, but facilities were abundant and close by.We also found that, in both neighbourhoods, senior citizens were reluctant to share their limitations and ask for support, despite differences in neighbourhood, ethnicity, age etc. Of course, this can be expected of seniors from the ‘silent generation’. However, they seemingly shared these emotions more easily with their peers than with professional researchers. ConclusionThe social-cultural context of the neighbourhood impacts the research process. Overall, co-research appears to be a fruitful method to involve senior citizens in decisions concerning the improvement of their neighbourhood. Aims and content of the workshopWe aim to:• present our reflections on the participative process of working with senior co-researchers in Amsterdam• exchange and discuss with the participants of the workshop the lessons learned on how to facilitate citizens’ participation in the community• discuss similar and future projects and possibilities for collaboration among the participants of the workshopContent of the workshop• Presentation• Exchange and discussion in small groups • Plenary discussion on possible collaboration projects aiming to enhance citizens’ participation in the community
