Records 1 - 20 / 319
Technical Limits in Circularity for Plastic Packages
Brouwer, M.T. ; Thoden van Velzen, E.U. ; Ragaert, Kim ; Klooster, Roland ten - \ 2020
Sustainability 12 (2020). - ISSN 2071-1050 - p. 1 - 29.
plastic packaging waste; recycling; recycling targets; polymer purity; quality of recycled plastics; limits
The current Dutch recycling value chain for plastic packaging waste (PPW) has not reached its full circularity potential, as is apparent from two Circular Performance Indicators (CPIs): net packaging recycling rate and average polymer purity of the recycled plastics. The performance of the recycling value chain can be optimised at four stages: packaging design, collection, sorting, and recycling. This study explores the maximally achievable performance of a circular PPW recycling value chain, in case all stakeholders would implement the required radical improvement measures in a concerted action. The effects of the measures were modelled with material flow analysis. For such a utopic scenario, a net plastic packaging recycling rate of 72% can be attained and the produced recycled plastics will have an average polymeric purity of 97%. This is substantially more than the net packaging recycling rate of 37% for 2017 and will exceed the EU target of 50% for 2025. In such an ideal circular value chain more recycled plastics are produced for more demanding applications, such as food packaging, compared to the current recycling value chain. However, all stakeholders would need to implement drastic and coordinated changes, signifying unprecedented investments, to achieve this optimal circular PPW recycling value chain. © 2020 by the authors. Licensee MDPI, Basel, Switzerland.
|Alkyl chain length of antioxidants modulates their activity in spray-dried emulsions
Klooster, Sten ten; Villeneuve, Pierre ; Bourlieu-Lacanal, C. ; Durand, E. ; Schroen, Karin ; Berton-Carabin, Claire - \ 2020
Transdisciplinary innovation in irrigated smallholder agriculture in africa
Froebrich, Jochen ; Ludi, Eva ; Bouarfa, Sami ; Rollin, Dominique ; Jovanovic, Nebo ; Roble, Maria ; Ajmi, Tarek ; Albasha, Rami ; Bah, Sékou ; Bahri, Haithem ; Barberá, Gonzalo ; Beek, Christy van; Cheviron, Bruno ; Chishala, Benson ; Clercq, Willem de; Coulibaly, Yacouba ; Dicko, Mohammed ; Diawara, Bandiougou ; Dolinska, Aleksandra ; Ducrot, Raphaëlle ; Erkossa, Teklu ; Famba, Sebastiao ; Fissahaye, Degol ; Miguel Garcia, Angel De; Habtu, Solomon ; Hanafi, Salia ; Harper, Julia ; Heesmans, Hanneke ; Jamin, Jean Yves ; van't Klooster, Kees ; Mason, Nathaniel ; Mailhol, Jean Claude ; Marlet, Serge ; Mekki, Insaf ; Musvoto, Constansia ; Mosello, Beatrice ; Mweetwa, Alice ; Oates, Naomi ; Phiri, Elijah ; Pradeleix, Ludivine ; Querner, Erik ; Rozanov, Andrei ; Ker Rault, Philippe ; Rougier, Jean Emmanuel ; Shepande, Chizumba ; Sánchez Reparaz, Maite ; Tangara, Bréhima ; Vente, Joris De; Witt, Marlene de; Xueliang, Cai ; Zairi, Abdelaziz - \ 2020
Irrigation and Drainage 69 (2020)S1. - ISSN 1531-0353 - p. 6 - 22.
participatory innovation - smallholder farming, irrigation - transdisciplinary approach
Boosting the productivity of smallholder farming systems continues to be a major need in Africa. Challenges relating to how to improve irrigation are multi-factor and multisectoral, and they involve a broad range of actors who must interact to reach decisions collectively. We provide a systematic reflection on findings from the research project EAU4Food, which adopted a transdisciplinary approach to irrigation for food security research in five case studies in Ethiopia, Mali, Mozambique, South Africa and Tunisia. The EAU4Food experiences emphasize that actual innovation at irrigated smallholder farm level remains limited without sufficient improvement of the enabling environment and taking note of the wider political economy environment. Most project partners felt at the end of the project that the transdisciplinary approach has indeed enriched the research process by providing different and multiple insights from actors outside the academic field. Local capacity to facilitate transdisciplinary research and engagement with practitioners was developed and could support the continuation and scaling up of the approach. Future projects may benefit from a longer time frame to allow for deeper exchange of lessons learned among different stakeholders and a dedicated effort to analyse possible improvements of the enabling environment from the beginning of the research process.
Monodisperse droplet formation by spontaneous and interaction based mechanisms in partitioned EDGE microfluidic device
Klooster, S. ten; Sahin, S. ; Schroën, K. - \ 2019
Scientific Reports 9 (2019). - ISSN 2045-2322
The partitioned EDGE droplet generation device is known for its’ high monodisperse droplet formation frequencies in two distinct pressure ranges, and an interesting candidate for scale up of microfluidic emulsification devices. In the current study, we test various continuous and dispersed phase properties and device geometries to unravel how the device spontaneously forms small monodisperse droplets (6–18 μm) at low pressures, and larger monodisperse droplets (>28 μm) at elevated pressures. For the small droplets, we show that the continuous phase inflow in the droplet formation unit largely determines droplet formation behaviour and the resulting droplet size and blow-up pressure. This effect was not considered as a factor of significance for spontaneous droplet formation devices that are mostly characterised by capillary numbers in literature. We then show for the first time that the formation of larger droplets is caused by physical interaction between neighbouring droplets, and highly dependent on device geometry. The insights obtained here are an essential step toward industrial emulsification based on microfluidic devices.
Herbal bathing: an analysis of variation in plant use among Saramaccan and Aucan Maroons in Suriname
Klooster, Charlotte I.E.A. van 't; Haabo, Vinije ; Vossen, Tessa ; Andel, Tinde van - \ 2018
Leiden University Medical Centre
herbals baths - medicinal plants - Suriname - Maroons - Saramaccan - Aucan - traditional knowledge - traditional medicine
Background Herbal baths play an important role in the traditional health care of Maroons living in the interior of Suriname. However, little is known on the differences in plant ingredients used among and within the Maroon groups. We compared plant use in herbal baths documented for Saramaccan and Aucan Maroons, to see whether similarity in species was related to bath type, ethnic group, or geographical location. We hypothesized that because of their dissimilar cultural background, they used different species for the same type of bath. We assumed, however, that plants used in genital baths were more similar, as certain plant ingredients (e.g., essential oils), are preferred in these baths. Methods We compiled a database from published and unpublished sources on herbal bath ingredients and constructed a presence/absence matrix per bath type and study site. To assess similarity in plant use among and within Saramaccan and Aucan communities, we performed three Detrended Correspondence Analyses on species level and the Jaccard Similarity Index to quantify similarity in bath ingredients. Results We recorded 349 plants used in six commonly used bath types: baby strength, adult strength, skin diseases, respiratory ailments, genital steam baths, and spiritual issues. Our results showed a large variation in plant ingredients among the Saramaccan and Aucans and little similarity between Saramaccans and Aucans, even for the same type of baths. Plant ingredients for baby baths and genital baths shared more species than the others. Even within the Saramaccan community, plant ingredients were stronger associated with location than with bath type. Conclusions Plant use in bathing was strongly influenced by study site and then by ethnicity, but less by bath type. As Maroons escaped from different plantations and developed their ethnomedicinal practices in isolation, there has been little exchange in ethnobotanical knowledge after the seventeenth century between ethnic groups. Care should be taken in extrapolating plant use data collected from one location to a whole ethnic community. Maroon plant use deserves more scientific attention, especially now as there are indications that traditional knowledge is disappearing.
Herbal bathing : An analysis of variation in plant use among Saramaccan and Aucan Maroons in Suriname
Klooster, Charlotte I.E.A. van 't; Haabo, Vinije ; Ruysschaert, Sofie ; Vossen, Tessa ; Andel, Tinde R. van - \ 2018
Journal of Ethnobiology and Ethnomedicine 14 (2018). - ISSN 1746-4269
Aucan - Herbal baths - Maroons - Medicinal plants - Saramaccan - Suriname - Traditional knowledge - Traditional medicine
Background: Herbal baths play an important role in the traditional health care of Maroons living in the interior of Suriname. However, little is known on the differences in plant ingredients used among and within the Maroon groups. We compared plant use in herbal baths documented for Saramaccan and Aucan Maroons, to see whether similarity in species was related to bath type, ethnic group, or geographical location. We hypothesized that because of their dissimilar cultural background, they used different species for the same type of bath. We assumed, however, that plants used in genital baths were more similar, as certain plant ingredients (e.g., essential oils), are preferred in these baths. Methods: We compiled a database from published and unpublished sources on herbal bath ingredients and constructed a presence/absence matrix per bath type and study site. To assess similarity in plant use among and within Saramaccan and Aucan communities, we performed three Detrended Correspondence Analyses on species level and the Jaccard Similarity Index to quantify similarity in bath ingredients. Results: We recorded 349 plants used in six commonly used bath types: baby strength, adult strength, skin diseases, respiratory ailments, genital steam baths, and spiritual issues. Our results showed a large variation in plant ingredients among the Saramaccan and Aucans and little similarity between Saramaccans and Aucans, even for the same type of baths. Plant ingredients for baby baths and genital baths shared more species than the others. Even within the Saramaccan community, plant ingredients were stronger associated with location than with bath type. Conclusions: Plant use in bathing was strongly influenced by study site and then by ethnicity, but less by bath type. As Maroons escaped from different plantations and developed their ethnomedicinal practices in isolation, there has been little exchange in ethnobotanical knowledge after the seventeenth century between ethnic groups. Care should be taken in extrapolating plant use data collected from one location to a whole ethnic community. Maroon plant use deserves more scientific attention, especially now as there are indications that traditional knowledge is disappearing.
Type 2 diabetes-related proteins derived from an in vitro model of inflamed fat tissue
Klooster, Jean Paul ten; Sotiriou, Alexandros ; Boeren, Sjef ; Vaessen, Stefan ; Vervoort, Jacques ; Pieters, Raymond - \ 2018
Archives of Biochemistry and Biophysics 644 (2018). - ISSN 0003-9861 - p. 81 - 92.
Adipocyte - AdipoQ - AUH - CSNK2A2 - Haptoglobin - IL6 - LPS - Macrophage - NAGK - NNMT - pCYT2 - STK39 - TNFα
Currently, there is a worldwide increase of patients with type 2 diabetes (T2D). During the progression of healthy obese to T2D status, there is an influx of immune cells, in particular macrophages, into visceral adipose tissue, accompanied by an increase of inflammatory cytokines, such as, IL6, TNFα and Hp. To get a better insight in the underlying mechanisms, we performed a quantitative LCMS analysis on a modified in vitro assay, combining 3T3L1 adipocytes and activated RAW264.7 macrophages, thus mimicking inflamed adipose tissue. Clinically known proteins, e.g. IL6, TNFα AdipoQ, complement factor C3, B and D were identified, thus confirming the assay. In addition, we found 54 new proteins that can potentially be used for research into the mechanism of T2D. Comparison of our results to a study on human visceral fat of obese non-diabetic and obese diabetic subjects, indicated that AUH, NAGK, pCYT2, NNMT, STK39 and CSNK2A2 might indeed be linked to insulin resistance in humans. Moreover, the expression of some of these genes was also altered in human blood samples at early or later stages of insulin desensitization. Overall, we conclude that the direct contact co-culture of 3T3L1 adipocytes with activated macrophages could be a mechanistically relevant and partially translational model of inflamed visceral adipose tissue.
Public Health Citizen Science; Perceived Impacts on Citizen Scientists: A Case Study in a Low-Income Neighbourhood in the Netherlands
Broeder, Lea den; Lemmens, Lidwien ; Uysal, Serfanim ; Kauw, Karin ; Weekenborg, Jitske ; Schönenberger, Michaela ; Klooster-Kwakkelstein, Simone ; Schoenmakers, Mieke ; Scharwächter, Willie ; Weerd, Annemarije van de; Baouchi, Samira El; Schuit, Albertine Jantine ; Wagemakers, Annemarie - \ 2017
Citizen Science: Theory and Practice 2 (2017)1. - ISSN 2057-4991 - 17 p.
Citizen science – the active participation of lay people in research – may yield crucial local knowledge and increase research capacity. Recently, there is growing interest to understand benefits for citizen scientists themselves. We studied the perceived impacts of participation in a public health citizen science project on citizen scientists in a disadvantaged neighbourhood in the Netherlands. Local citizen scientists, characterised by low income and low educational level – many of whom were of migrant origin – were trained to interview fellow residents about health-enhancing and health-damaging neighbourhood features. Experiences of these citizen scientists were collected through focus groups and interviews and analysed using a theoretical model of potential citizen science benefits. The results show that the citizen scientists perceived participation in the project as a positive experience. They acquired a broader understanding of health and its determinants and knowledge about healthy lifestyles, and took action to change their own health behaviour. They reported improved self confidence and social skills, and expanded their network across cultural boundaries. Health was perceived as a topic that helped people with different backgrounds to relate to one another. The project also induced joint action to improve the neighbourhood’s health. We conclude that citizen science benefits participants with low educational or literacy level. Moreover, it seems to be a promising approach that can help promote health in underprivileged communities by strengthening personal skills and social capital. However, embedding projects in broader health promotion strategies and long-term engagement of citizen scientists should be pursued to accomplish this.
Patterning of plant cell wall deposition by cortical microtubules
‘t Klooster, Kris Joppe van - \ 2017
Wageningen University. Promotor(en): J. van der Gucht; B.M. Mulder, co-promotor(en): M.J. Ketelaar; J.J.W.A. van Loon. - Wageningen : Wageningen University - ISBN 9789463436229 - 113
Plant cells are surrounded by cell walls. Cell walls provide strength to protect and shape the cells they surround. Structural strength is particularly important in the water conducting tissue of the xylem. Water and nutrient transport is driven by water evaporation at the leaves, generating a negative pressure in the tubular xylem vessels. Patterned cell wall reinforcements are deposited during the development of these cells that function in counteracting the negative pressure. The cell wall reinforcements are deposited in a diverse number of patterns. Secondary cell wall thickenings in the form of rings and spirals provide physical strength, while allowing elongation of the surrounding tissue in the newly grown plant parts. Plant cell walls consist of a mixture of polysaccharides, forming an intricate network with cellulose microfibrils as the main load-bearing component. The cortical microtubule array dictates the direction and location of newly polymerised cellulose microfibrils in primary cell wall deposition. In this thesis, I focus on understanding if and how microtubule dynamics control the patterning of secondary cell wall position. Which self-organizing properties of microtubules change to generate a microtubule pattern and how is this pattern translated to a patterned cell wall deposition during protoxylem formation? We measured the microtubule dynamicity parameters growth velocity, shrink velocity, rescue rate and catastrophe rate which are important for the self-organizational capability of the microtubule array. We show that the rescue and catastrophe rate increases in the microtubule gap area compared to the microtubule band area. Via stochastic computer simulations we show that a 2-fold increase of the catastrophe rate is sufficient to generate microtubule bands and gaps. Furthermore we investigate if gravity is a factor able to influence the reorganization of the microtubule array during protoxylem formation. Altogether, the results indicate that local changes in the rescue and catastrophe rate are responsible for the generation of microtubule bands and gaps over time during protoxylem formation.
N-Docosahexaenoyl Dopamine, an Endocannabinoid-like Conjugate of Dopamine and the n-3 Fatty Acid Docosahexaenoic Acid, Attenuates Lipopolysaccharide-Induced Activation of Microglia and Macrophages via COX-2
Wang, Ya ; Plastina, Pierluigi ; Vincken, Jean Paul ; Jansen, Renate ; Balvers, Michiel ; Klooster, Jean Paul ten; Gruppen, Harry ; Witkamp, Renger ; Meijerink, Jocelijn - \ 2017
ACS Chemical Neuroscience 8 (2017)3. - ISSN 1948-7193 - p. 548 - 557.
cyclooxygenase-2 - Endocannabinoids - interleukin-6 - N-arachidonoyl dopamine - N-docosahexaenoyl dopamine - prostaglandin E
Several studies indicate that the n-3 long-chain polyunsaturated fatty acid docosahexaenoic acid (DHA) contributes to an attenuated inflammatory status in the development of neurodegenerative disorders, such as Alzheimer’s and Parkinson’s disease. To explain these effects, different mechanisms are being proposed, including those involving endocannabinoids and related signaling molecules. Many of these compounds belong to the fatty acid amides, conjugates of fatty acids with biogenic amines. Conjugates of DHA with ethanolamine or serotonin have previously been shown to possess anti-inflammatory and potentially neuroprotective properties. Here, we synthesized another amine conjugate of DHA, N-docosahexaenoyl dopamine (DHDA), and tested its immune-modulatory properties in both RAW 264.7 macrophages and BV-2 microglial cells. N-Docosahexaenoyl dopamine significantly suppressed the production of nitric oxide (NO), the cytokine interleukin-6 (IL-6), and the chemokines macrophage-inflammatory protein-3α (CCL20) and monocyte chemoattractant protein-1 (MCP-1), whereas its parent compounds, dopamine and DHA, were ineffective. Further exploration of potential effects of DHDA on key inflammatory mediators revealed that cyclooxygenase-2 (COX-2) mRNA level and production of prostaglandin E2 (PGE2) were concentration-dependently inhibited in macrophages. In activated BV-2 cells, PGE2 production was also reduced, without changes in COX-2 mRNA levels. In addition, DHDA did not affect NF-kB activity in a reporter cell line. Finally, the immune-modulatory activities of DHDA were compared with those of N-arachidonoyl dopamine (NADA) and similar potencies were found in both cell types. Taken together, our data suggest that DHDA, a potentially endogenous endocannabinoid, may be an additional member of the group of immune-modulating n-3 fatty acid-derived lipid mediators.
Docosahexaenoyl Serotonin, an endogenously formed n-3 fatty acid-serotonin conjugate, has anti-inflammatory properties by attenuating IL23–IL17 signalling in macrophages
Poland, M.C.R. ; Klooster, Jean Paul ten; Wang, Zheng ; Pieters, Raymond ; Boekschoten, M.V. ; Witkamp, R.F. ; Meijerink, J. - \ 2016
Mus musculus - GSE87369 - PRJNA344499
Conjugates of fatty acids and amines, including endocannabinoids, are known to play important roles as endogenous signalling molecules. Among these, the ethanolamine conjugate of the n-3 poly unsaturated long chain fatty acid (PUFA) docosahexaenoic acid (22:6n-3) (DHA) was shown to possess strong anti-inflammatory properties. Previously, we identified the serotonin conjugate of DHA, docosahexaenoyl serotonin (DHA-5-HT), in intestinal tissues and showed that its levels are markedly influenced by intake of n-3 PUFAs. However, its biological roles remain to be elucidated. Here, we show that DHA-5-HT possesses potent anti-inflammatory properties by attenuating the IL-23-IL-17 signalling cascade in lipopolysaccharide (LPS)-stimulated RAW264.7 macrophages. Transcriptome analysis revealed that DHA-5-HT down-regulates LPS-induced genes, particularly those involved in generating a CD4 + Th17 response. Hence, levels of PGE2, IL-6, IL-1β, and IL-23, all pivotal macrophage-produced mediators driving the activation of pathogenic Th17 cells in a concerted way, were found to be significantly suppressed by concentrations as low as 100–500 nM DHA-5-HT. Furthermore, DHA-5-HT inhibited the ability of RAW264.7 cells to migrate and downregulated chemokines like MCP-1, CCL-20, and gene-expression of CCL-22 and of several metalloproteinases. Gene set enrichment analysis (GSEA) suggested negative overlap with gene sets linked to inflammatory bowel disease (IBD) and positive overlap with gene sets related to the Nrf2 pathway. The specific formation of DHA-5-HT in the gut, combined with increasing data underlining the importance of the IL-23-IL-17 signalling pathway in the aetiology of many chronic inflammatory diseases merits further investigation into its potential as therapeutic compound in e.g. IBD or intestinal tumorigenesis.
The Health Embassy : Resident benefits of Citizen Science in a low SES Dutch neighbourhood Lea Den Broeder
Broeder, L. den; Kauw, K. ; Uysal, S. ; Schönenberger, M. ; Kwakkelstein-Klooster, S. ; Schoenmakers, M. ; Scharwächter, W. ; Schuit, A.J. ; Wagemakers, A. - \ 2016
European Journal of Public Health 26 (2016)1. - ISSN 1101-1262 - p. 244 - 245.
Slotermeer is a disadvantaged neighbourhood in Amsterdam, the Netherlands. Local policy makers want to collect information about resident views as a basis for health enhancing policies. A Citizen Science approach where residents interview people in the neighbourhood was applied to collect such information. But how does this approach affect these residents themselves?
The noncaloric sweetener rebaudioside a stimulates glucagon-like peptide 1 release and increases enteroendocrine cell numbers in 2-dimensional mouse organoids derived from different locations of the intestine
Wielen, Nikkie van der; Klooster, Jean Paul ten; Muckenschnabl, Susanne ; Pieters, Raymond ; Hendriks, Henk F.J. ; Witkamp, Renger F. ; Meijerink, Jocelijn - \ 2016
The Journal of Nutrition 146 (2016)12. - ISSN 0022-3166 - p. 2429 - 2435.
Duodenum - GLP-1 - Glucagon-like peptide 1 - Gut hormone - Ileum - Jejunum - Minigut - Organoids - Peptide YY - Stevia
Background: Glucagon-like peptide 1 (GLP-1) contributes to satiety and plays a pivotal role in insulin secretion and glucose homeostasis. Similar to GLP-1, peptide YY (PYY) and cholecystokinin also influence food intake. The secretion of these hormones by enteroendocrine cells along the intestine is modulated by nutrients. Preparations from the Stevia rebaudiana plant, including rebaudioside A, are increasingly being used as noncaloric sweeteners. Objective: We investigated the effects of rebaudioside A on enteroendocrine cells by assessing both cell numbers as well as their secretory capacity in an organoid model. Methods: A 2-dimensional organoid model derived from duodenal, jejunal, and ileal crypts of a C57BL/6J mouse was developed and characterized with the use of gene expression and immunofluorescence. We stimulated these organoids with 10 mmol/L rebaudioside A for 1 h and measured their GLP-1, PYY, and cholecystokinin release. We also analyzed the effects of rebaudioside A on gene expression in enteroendocrine cells after an 18-h incubation. Results: The 2-dimensional organoids contained crypt cells and differentiated villus cells, including enterocytes and goblet and enteroendocrine cells. These enteroendocrine cells stained positive for GLP-1, PYY, and serotonin. The cultured 2-dimensional organoids maintained their location-specific gene expression patterns. Compared with the control, rebaudioside A induced GLP-1 secretion 1.7-fold in the duodenum (P <0.01), 2.2-fold in the jejunum (P <0.01), and 4.3-fold in the ileum (P <0.001). PYY release was increased by rebaudioside A 3-fold in the ileumcompared with the control (P <0.05). Long-term (18-h) stimulation with the sweetener induced the expression of the enteroendocrine-specific markers chromogranin A, glucagon, Pyy, and cholecystokinin 3.5- (P <0.001), 3.5- (P <0.001), 3.8- (P <0.05), and 6.5-fold (P <0.001), respectively. Conclusions: These results show novel ex vivo effects of rebaudioside A on enteroendocrine cells of the mouse small intestine and highlight potentially new applications for rebaudioside A in metabolic diseases.
Docosahexaenoyl serotonin, an endogenously formed n-3 fatty acid-serotonin conjugate has anti-inflammatory properties by attenuating IL-23–IL-17 signaling in macrophages
Poland, Mieke ; Klooster, Jean Paul ten; Wang, Zheng ; Pieters, Raymond ; Boekschoten, Mark ; Witkamp, Renger ; Meijerink, Jocelijn - \ 2016
Biochimica et Biophysica Acta. Molecular and Cell Biology of Lipids 1861 (2016)12. - ISSN 1388-1981 - p. 2020 - 2028.
Acyl serotonines - DHA - DHA-5-HT - Endocannabinoids - Intestine - Nrf2
Conjugates of fatty acids and amines, including endocannabinoids, are known to play important roles as endogenous signaling molecules. Among these, the ethanolamine conjugate of the n-3 poly unsaturated long chain fatty acid (PUFA) docosahexaenoic acid (22:6n-3) (DHA) was shown to possess strong anti-inflammatory properties. Previously, we identified the serotonin conjugate of DHA, docosahexaenoyl serotonin (DHA-5-HT), in intestinal tissues and showed that its levels are markedly influenced by intake of n-3 PUFAs. However, its biological roles remain to be elucidated. Here, we show that DHA-5-HT possesses potent anti-inflammatory properties by attenuating the IL-23-IL-17 signaling cascade in lipopolysaccharide (LPS)-stimulated RAW264.7 macrophages. Transcriptome analysis revealed that DHA-5-HT down-regulates LPS-induced genes, particularly those involved in generating a CD4+ Th17 response. Hence, levels of PGE2, IL-6, IL-1β, and IL-23, all pivotal macrophage-produced mediators driving the activation of pathogenic Th17 cells in a concerted way, were found to be significantly suppressed by concentrations as low as 100–500 nM DHA-5-HT. Furthermore, DHA-5-HT inhibited the ability of RAW264.7 cells to migrate and downregulated chemokines like MCP-1, CCL-20, and gene-expression of CCL-22 and of several metalloproteinases. Gene set enrichment analysis (GSEA) suggested negative overlap with gene sets linked to inflammatory bowel disease (IBD) and positive overlap with gene sets related to the Nrf2 pathway. The specific formation of DHA-5-HT in the gut, combined with increasing data underlining the importance of the IL-23-IL-17 signaling pathway in the etiology of many chronic inflammatory diseases merits further investigation into its potential as therapeutic compound in e.g. IBD or intestinal tumorigenesis.
Patterns in medicinal plant knowledge and use in a Maroon village in Suriname
Klooster, Charlotte van 't; Andel, Tinde van; Reis, Ria - \ 2016
Journal of Ethnopharmacology 189 (2016). - ISSN 0378-8741 - p. 319 - 330.
Maroons - Medicinal plants - Saramaccan - Suriname - Traditional knowledge - Traditional medicines
Ethnopharmacological relevance Traditional medicine plays an important role in the primary health care practices of Maroons living in the interior of Suriname. Large numbers of medicinal plants are employed to maintain general health and cure illnesses. Little is known, however, on how knowledge of herbal medicine varies within the community and whether plant use remains important when modern health care becomes available. Aim of the study To document the diversity in medicinal plant knowledge and use in a remote Saramaccan Maroon community and to assess the importance of medicinal plants vis a vis locally available modern healthcare. We hypothesized that ailments which could be treated by the village health center would be less salient in herbal medicine reports. Methods During three months fieldwork in the Saramaccan village of Pikin Slee, ethnobotanical data were collected by means of participant observations, voucher collections and 27 semi-structured interviews and informal discussions with 20 respondents. To test whether knowledge of medicinal plant species was kept within families, we performed a Detrended Correspondence Analysis. Results In total, 110 medicinal plant species were recorded, with 302 health use reports and 72 uses, mostly related to general health concerns (42%), diseases of the digestive system (10%), musculoskeletal system and fever (each 7%). Bathing was the most important mode of application. Most health use reports related to cure (58%) and health promotion (39%), while disease prevention played a minor role. Traditional medicine not only treated cultural illnesses, but also health concerns that could be treated with locally available modern medicines. Knowledge of medicinal plant species is not strictly kept within families, but also shared with friends. Certain recipes and applications, however, may be specific family knowledge. Conclusion Medicinal plants play a very important role in the daily lives of the Pikin Slee villagers. Plant use reflects actual health concerns, but as modern medicines are available for most of these concerns, the use of herbal medicines seems to be a deep rooted cultural preference, especially when concerned with cultural illnesses and health promotion. Locally provided healthcare could be enriched if traditional knowledge, illness concepts, and medicinal plant uses could fit into a larger, community-oriented framework.
Transition-state theory predicts clogging at the microscale
Laar, T. van de; Klooster, S. ten; Schroën, K. ; Sprakel, J. - \ 2016
Scientific Reports 6 (2016). - ISSN 2045-2322
Clogging is one of the main failure mechanisms encountered in industrial processes such as membrane filtration. Our understanding of the factors that govern the build-up of fouling layers and the emergence of clogs is largely incomplete, so that prevention of clogging remains an immense and costly challenge. In this paper we use a microfluidic model combined with quantitative real-time imaging to explore the influence of pore geometry and particle interactions on suspension clogging in constrictions, two crucial factors which remain relatively unexplored. We find a distinct dependence of the clogging rate on the entrance angle to a membrane pore which we explain quantitatively by deriving a model, based on transition-state theory, which describes the effect of viscous forces on the rate with which particles accumulate at the channel walls. With the same model we can also predict the effect of the particle interaction potential on the clogging rate. In both cases we find excellent agreement between our experimental data and theory. A better understanding of these clogging mechanisms and the influence of design parameters could form a stepping stone to delay or prevent clogging by rational membrane design.
Payyappallimana, U. ; Subramanian, M. ; Timoshyna, A. ; Graz, B. ; Leaman, D. ; Bussmann, R.W. ; Hariramamurthi, G. ; Shankar, D. ; Klooster, C.I.E.A. van 't; Bodeker, G. ; Sekagya, Y. ; Hemstra, W. ; Gomez, F. ; Verschuuren, B. ; Ravin, E. de; Ligare, J. ; Reid, A.M. ; Petersen, L.M. - \ 2015
In: Connecting Global Priorities: Biodiversity and Human Health World Health Organization - ISBN 9789241508537 - p. 180 - 199.
Comparative study of nitrate leaching models on a regional scale
Roelsma, J. ; Hendriks, R.F.A. - \ 2014
Science of the Total Environment 499 (2014). - ISSN 0048-9697 - p. 481 - 496.
agricultural land-use - soil-crop model - groundwater nitrate - sandy soils - drinking-water - system stone - netherlands - nitrogen - losses - simulation
In Europe and North America the application of high levels of manure and fertilisers on agricultural land has led to high levels of nitrate concentrations in groundwater, in particular on sandy soils. For the evaluation of the development of the quality of groundwater a sound quantitative basis is needed. In this paper a comparison has been made between observations of nitrate concentrations in the upper groundwater and predictions of nitrate leaching models. Observations of nitrate concentrations in the upper groundwater at three different locations in regions with mainly sandy soils in the eastern and northern part of the Netherlands were used to test the performance of the simulation models to predict nitrate leaching to the upper groundwater. Four different types of simulation models of different levels of complexity and input data requirement were tested. These models are ANIMO (dynamic complex process oriented model), MM-WSV (meta-model), WOG (simple process oriented model) and NURP (semi-empiric model). The performance of the different simulation models was evaluated using statistical criteria. The dynamic complex process oriented ANIMO model showed the best model performance. The MM-WSV meta-model was the second best model, whilst the simple process oriented WOG model produced the worst model performance. The best model performance showed the dynamic complex process oriented ANIMO model in predicting the nitrate concentrations in the upper groundwater of the Klooster catchment. The good performance of the ANIMO model for this catchment can be explained by the additional information about the use of manure and fertilisers at farm level in this study area. The ANIMO model may be a good tool to predict nitrate concentrations in the upper groundwater on a regional scale. However, the use of a detailed process oriented simulation model requires a comprehensive set of input data. If such a comprehensive data-set is not available the MM-WSV model (meta-model) proves to be a good alternative. The WOG and NURP models are suitable for long term (>8 years) predictions of average nitrate concentrations in the upper groundwater on a regional scale. (C) 2014 Elsevier B.V. All rights reserved.
Local plant names reveal that enslaved Africans recognized substantial parts of the New World flora
Andel, T.R. van; Klooster, E.A. van 't; Quiroz Villarreal, D.K. ; Towns, A.M. ; Ruysschaert, S. ; Berg, M. van den - \ 2014
Proceedings of the National Academy of Sciences of the United States of America 111 (2014)50. - ISSN 0027-8424 - p. E5346 - E5353.
surinamese creoles - west-africa - medicine - market - benin
How did the forced migration of nearly 11 million enslaved Africans to the Americas influence their knowledge of plants? Vernacular plant names give insight into the process of species recognition, acquisition of new knowledge, and replacement of African species with American ones. This study traces the origin of 2,350 Afro-Surinamese (Sranantongo and Maroon) plant names to those plant names used by local Amerindians, Europeans, and related groups in West and Central Africa. We compared vernacular names from herbarium collections, literature, and recent ethnobotanical fieldwork in Suriname, Ghana, Benin, and Gabon. A strong correspondence in sound, structure, and meaning among Afro-Surinamese vernaculars and their equivalents in other languages for botanically related taxa was considered as evidence for a shared origin. Although 65% of the Afro-Surinamese plant names contained European lexical items, enslaved Africans have recognized a substantial part of the neotropical flora. Twenty percent of the Sranantongo and 43% of the Maroon plant names strongly resemble names currently used in diverse African languages for related taxa, represent translations of African ones, or directly refer to an Old World origin. The acquisition of new ethnobotanical knowledge is captured in vernaculars derived from Amerindian languages and the invention of new names for neotropical plants from African lexical terms. Plant names that combine African, Amerindian, and European words reflect a creolization process that merged ethnobotanical skills from diverse geographical and cultural sources into new Afro-American knowledge systems. Our study confirms the role of Africans as significant agents of environmental knowledge in the New World.
Hope for the redshank : Agricultural nature management on a large scale
Berendse, F. ; Klooster, C.E. van 't - \ 2013