Staff Publications

Staff Publications

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    'Staff publications' is the digital repository of Wageningen University & Research

    'Staff publications' contains references to publications authored by Wageningen University staff from 1976 onward.

    Publications authored by the staff of the Research Institutes are available from 1995 onwards.

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Dietary supplementation of 11 different plant extracts on the antioxidant capacity of blood and selected tissues in lightweight lambs
Leal, Leonel N. ; Jordán, María J. ; Bello, José M. ; Otal, Julio ; Hartog, Leo A. den; Hendriks, Wouter H. ; Martín-Tereso, Javier - \ 2019
Journal of the Science of Food and Agriculture 99 (2019)9. - ISSN 0022-5142 - p. 4296 - 4303.
kidney - lambs - liver - muscle - plant extracts - plasma

BACKGROUND: Due to the growing public concern regarding the addition of chemical antioxidants to foods, focus has shifted towards natural alternatives. Because of their antioxidant potential, culinary herbs and spices have long been used to extend the shelf-life of foods. However, a better understanding of the fate of these products following intake is required to assess their use in lamb diets. RESULTS: Two hundred and eighty-eight Rasa Aragonesa male lambs (70 days old) were supplemented (5.0 g kg −1 compound feed) with bay, marjoram, oregano, rosemary, thyme, turmeric, cumin, caraway, dill, cinnamon and nutmeg extracts for 14 days before slaughter. Dietary supplementation with plant extracts had no effect on intake, growth performance or antioxidant activity in blood (TEAC values). In muscle, nutmeg supplementation increased (P < 0.05) the radical-scavenging capacity (TEAC), whereas a decrease in the radical-scavenging capacity was found for lambs supplemented with oregano, dill, cinnamon and nutmeg (ORAC values). In liver, nutmeg supplementation increased (P < 0.05) the antioxidant capacity (TEAC), whereas bay (ORAC), turmeric, cinnamon and nutmeg (DPPH values) decreased (P < 0.05) the radical-scavenging capacity of the tissue. In kidney, a lower (P < 0.05) radical-scavenging capacity (TEAC values) was found in lambs supplemented with oregano, cumin and caraway, whereas, turmeric, cumin, caraway, cinnamon and nutmeg increased (P < 0.05) the antioxidant capacity (ORAC values) in kidney. CONCLUSION: Supplementation of lamb diets with plant extracts affected radical-scavenging activity in muscle, liver and kidney. However, due to the divergent results of the different assays for the same tissue, it is not advisable to discriminate plant extracts using this approach.

Plasma and Serum Metabolite Association Networks : Comparability within and between Studies Using NMR and MS Profiling
Suarez-Diez, Maria ; Adam, Jonathan ; Adamski, Jerzy ; Chasapi, Styliani A. ; Luchinat, Claudio ; Peters, Annette ; Prehn, Cornelia ; Santucci, Claudio ; Spyridonidis, Alexandros ; Spyroulias, Georgios A. ; Tenori, Leonardo ; Wang-Sattler, Rui ; Saccenti, Edoardo - \ 2017
Journal of Proteome Research 16 (2017)7. - ISSN 1535-3893 - p. 2547 - 2559.
blood - correlations - differential network analysis - low molecular weight metabolites - mutual information - network inference - network topology - plasma - serum
Blood is one of the most used biofluids in metabolomics studies, and the serum and plasma fractions are routinely used as a proxy for blood itself. Here we investigated the association networks of an array of 29 metabolites identified and quantified via NMR in the plasma and serum samples of two cohorts of ∼1000 healthy blood donors each. A second study of 377 individuals was used to extract plasma and serum samples from the same individual on which a set of 122 metabolites were detected and quantified using FIA-MS/MS. Four different inference algorithms (ARANCE, CLR, CORR, and PCLRC) were used to obtain consensus networks. The plasma and serum networks obtained from different studies showed different topological properties with the serum network being more connected than the plasma network. On a global level, metabolite association networks from plasma and serum fractions obtained from the same blood sample of healthy people show similar topologies, and at a local level, some differences arise like in the case of amino acids.
The assessment of selectivity in different quadrupole-orbitrap mass spectrometry acquisition
Berendsen, B.J.A. ; Wegh, R.S. ; Meijer, T. ; Nielen, M.W.F. - \ 2015
Journal of the American Society for Mass Spectrometry 26 (2015)2. - ISSN 1044-0305 - p. 337 - 346.
performance liquid-chromatography - veterinary drugs - confirmation - metabolites - residues - plasma - food - meat
Selectivity of the confirmation of identity in liquid chromatography (tandem) mass spectrometry using Q-Orbitrap instrumentation was assessed using different acquisition modes based on a representative experimental data set constructed from 108 samples, including six different matrix extracts and containing over 100 analytes each. Single stage full scan, all ion fragmentation, and product ion scanning were applied. By generating reconstructed ion chromatograms using unit mass window in targeted MS(2), selected reaction monitoring (SRM), regularly applied using triple-quadrupole instruments, was mimicked. This facilitated the comparison of single stage full scan, all ion fragmentation, (mimicked) SRM, and product ion scanning applying a mass window down to 1 ppm. Single factor Analysis of Variance was carried out on the variance (s(2)) of the mass error to determine which factors and interactions are significant parameters with respect to selectivity. We conclude that selectivity is related to the target compound (mainly the mass defect), the matrix, sample clean-up, concentration, and mass resolution. Selectivity of the different instrumental configurations was quantified by counting the number of interfering peaks observed in the chromatograms. We conclude that precursor ion selection significantly contributes to selectivity: monitoring of a single product ion at high mass accuracy with a 1 Da precursor ion window proved to be equally selective or better to monitoring two transition products in mimicked SRM. In contrast, monitoring a single fragment in all ion fragmentation mode results in significantly lower selectivity versus mimicked SRM. After a thorough inter-laboratory evaluation study, the results of this study can be used for a critical reassessment of the current identification points system and contribute to the next generation of evidence-based and robust performance criteria in residue analysis and sports doping.
High natural antibody titers of indigenous chickens are related with increased hazard in confinement
Wondmeneh, E. ; Arendonk, J.A.M. van; Waaij, E.H. van der; Ducro, B.J. ; Parmentier, H.K. - \ 2015
Poultry Science 94 (2015)7. - ISSN 0032-5791 - p. 1493 - 1498.
laying hens - responses - survival - immunity - corticosterone - population - strains - stress - innate - plasma
Natural antibody (NAb) levels and survival rates were evaluated in 4 breeds of laying hens in Ethiopia: indigenous, improved indigenous, exotic layer, and crossbred. Titers of NAb isotypes IgG and IgM binding keyhole limpet hemocyanin (KLH) in serum were measured at 20, 26, 35, and 45 wk age. Repeated-measure ANOVA showed that IgG and IgM levels vary with time within each breed (P <0.05). Indigenous chickens had significantly (P <0.05) higher NAb levels at all ages. The Cox proportional hazard analysis showed increased hazard with increased levels of NAbs in the exotic layers (P <0.05). However, the reduced hazards with increased levels of NAbs were not significant in the improved indigenous and crossbred chickens. Indigenous chickens showed increased hazard with increasing levels of NAb (P > 0.05). We concluded that not only the NAb levels but also the effect of Nabs on survival vary between indigenous and improved breeds. The results indicate that NAb levels are associated with survival in elite (improved) breeds, but are associated with increased hazard in indigenous chickens.
Induced lung inflammation and dietary protein supply affect nitrogen retention and amino acid metabolism in growing pigs
Kampman-van de Hoek, E. ; Sakkas, P. ; Gerrits, W.J.J. ; Borne, J.J.G.C. van den; Peet-Schwering, C.M.C. van der; Jansman, A.J.M. - \ 2015
The British journal of nutrition 113 (2015)3. - ISSN 0007-1145 - p. 414 - 425.
immune-system activation - acute-phase proteins - body protein - tryptophan - plasma - growth - piglets - disease - sepsis - rats
It is hypothesised that during immune system activation, there is a competition for amino acids (AA) between body protein deposition and immune system functioning. The aim of the present study was to quantify the effect of immune system activation on N retention and AA metabolism in growing pigs, depending on dietary protein supply. A total of sixteen barrows received an adequate (Ad) or restricted (Res) amount of dietary protein, and were challenged at day 0 with intravenous complete Freund's adjuvant (CFA). At days - 5, 3 and 8, an irreversible loss rate (ILR) of eight AA was determined. CFA successfully activated the immune system, as indicated by a 2- to 4-fold increase in serum concentrations of acute-phase proteins (APP). Pre-challenge C-reactive protein concentrations were lower (P<0·05) and pre- and post-challenge albumin tended to be lower in Res-pigs. These findings indicate that a restricted protein supply can limit the acute-phase response. CFA increased urinary N losses (P= 0·04) and tended to reduce N retention in Ad-pigs, but not in Res-pigs (P= 0·07). The ILR for Val was lower (P= 0·05) at day 8 than at day 3 in the post-challenge period. The ILR of most AA, except for Trp, were strongly affected by dietary protein supply and positively correlated with N retention. The correlations between the ILR and APP indices were absent or negative, indicating that changes in AA utilisation for APP synthesis were either not substantial or more likely outweighed by a decrease in muscle protein synthesis during immune system activation in growing pigs.
Evaluation of the Discriminative Potential of a Novel Biomarker for Estradiol Treatments in Bovine Animals
Regal, P. ; Blokland, M.H. ; Fente, C.A. ; Sterk, S.S. ; Cepeda, A. ; Ginkel, L.A. van - \ 2015
Journal of Agricultural and Food Chemistry 63 (2015)1. - ISSN 0021-8561 - p. 370 - 378.
tandem mass-spectrometry - timed artificial-insemination - beef-cattle - protein biomarkers - gene-expression - hormone abuse - plasma - 17-beta-estradiol - estrogen - detect
The endogenous occurrence of natural hormones obstructs the application of classical targeted methods as confirmatory options. In the case of estradiol, the ultimate confirmation of its exogenous administration relies on gas chromatography coupled to combustion/isotope ratio mass spectrometry (GC-C/IRMS). A serum dipeptide composed of pyroglutamic acid and phenylalanine was identified as a potential biomarker of estradiol treatments in adult cows. To evaluate its potential to pinpoint suspicious samples, samples from prepubertal females under different estrogenic treatments have been analyzed. The results confirmed the up-regulation of the dipeptide in adult bovines. The 2-week-old females exhibited short-lasting responses only in a few animals. The 6-month-old female showed a delayed but clear increase on the biomarker level. The composition of the anabolic preparations, the dose, and/or the administration route are possible additional reasons for the reduced response in young animals. A comparison to previous results reported by various researchers is included.
A metabolic profile is associated with the risk of incident coronary heart disease
Vaarhorst, A. ; Verhoeven, A. ; Weller, C.M. ; Bohringer, S. ; Brandt, P.A. van den; Greevenbroek, M.M. ; Merry, A.H. ; Verschuren, W.M.M. ; Boer, J.M.A. ; Feskens, E.J.M. ; Heijmans, B.T. ; Slagboom, P.E. - \ 2014
American Heart Journal 168 (2014)1. - ISSN 0002-8703 - p. 45 - 52.e7.
artery-disease - cardiovascular events - population - prediction - plasma - phosphatidylcholine - metabonomics - netherlands - mortality - cohort
Background Metabolomics, defined as the comprehensive identification and quantification of low-molecular-weight metabolites to be found in a biological sample, has been put forward as a potential tool for classifying individuals according to their risk of coronary heart disease (CHD). Here, we investigated whether a single-point blood measurement of the metabolome is associated with and predictive for the risk of CHD.
ANGPTL4 is produced by entero-endocrine cells in the human intestinal tract
Alex, S. ; Lichtenstein, L.L. ; Dijk, W. ; Mensink, R.P. ; Tan, N.S. ; Kersten, A.H. - \ 2014
Histochemistry and Cell Biology 141 (2014)4. - ISSN 0948-6143 - p. 383 - 391.
angiopoietin-like protein-4 - activated receptor-gamma - diet-induced obesity - lipoprotein-lipase - chromogranin-a - fatty-acids - enteroendocrine cells - gut microbiota - target gene - plasma
Gut hormones produced by entero-endocrine cells (EEC) located throughout the gastrointestinal tract play a major role in the regulation of glucose and energy homeostasis. Angiopoietin-like 4 (ANGPTL4, also referred to as fasting induced adipose factor) is a secreted factor involved in regulation of lipid homeostasis and has been proposed as circulating mediator between the gut microbiota and fat storage in adipose tissue, although discordant data exist. Currently, little is known about the site and regulation of ANGPTL4 production in the intestine. Here, we show using immunohistochemistry and immunofluorescence that cells positive for ANGPTL4 are scattered along the epithelial layer in the human small and large intestine. ANGPTL4-positive cells exhibit typical features of EEC characterized by large ANGPTL4-positive secretory granules directed towards the basolateral side. In support, extensive overlap was observed between ANGPTL4-positive cells and cells positive for the entero-endocrine marker chromogranin A. Higher resolution images revealed that ANGPTL4 and chromogranin A are partially present in distinct intracellular vesicles. Using entero-endocrine HuTu-80 cells, ANGPTL4 secretion was shown to be induced by short chain fatty acids and reduced by bile acids. Finally, levels of ANGPTL4 in human plasma were significantly decreased following meal consumption. In conclusion, ANGPTL4 is produced by EEC in human intestine and expression may be regulated by short chain fatty acids and bile acids.
Omega-3 long-chain fatty acids strongly induce angiopoietin-like 4 in humans
Brands, M. ; Sauerwein, H.P. ; Ackermans, M.T. ; Kersten, A.H. ; Serlie, M.J. - \ 2013
Journal of Lipid Research 54 (2013)3. - ISSN 0022-2275 - p. 615 - 621.
triglyceride-metabolism - lipoprotein-lipase - target gene - plasma - angptl4 - protein - increase - insulin - glucose - hyperlipidemia
Angiopoietin-like 4 (ANGPTL4) is a regulator of LPL activity. In this study we examined whether different fatty acids have a differential effect on plasma ANGPTL4 levels during hyperinsulinemia in healthy lean males. In 10 healthy lean males, 3 hyperinsulinemic euglycemic clamps were performed during concomitant 6 h intravenous infusion of soybean oil (Intralipid (R); rich in PUFA), olive oil (Clinoleic (R); rich in MUFA) and control saline. In 10 other healthy lean males, 2 hyperinsulinemic clamps were performed during infusion of a mixed lipid emulsion containing a mixture of fish oil (FO), medium-chain triglycerides (MCTs), and long-chain triglycerides (LCTs) (FO/MCT/LCT; SMOFlipid (R)) or saline. FFA levels of approximately 0.5 mmol/l were reached during each lipid infusion. Plasma ANGPTL4 decreased during hyperinsulinemia by 32% (18-52%) from baseline. This insulin-mediated decrease in ANGPTL4 concentrations was partially reduced during concomitant infusion of olive oil and completely blunted during concomitant infusion of soybean oil and FO/MCT/LCT. The reduction in insulin sensitivity was similar between all lipid infusions. In accordance, incubation of rat hepatoma cells with the polyunsaturated fatty acid C22:6 increased ANGPTL4 expression by 70-fold, compared with 27-fold by the polyunsaturated fatty acid C18:2, and 15-fold by the monounsaturated fatty acid C18:1. These results suggest that ANGPTL4 is strongly regulated by fatty acids in humans, and is also dependent on the type of fatty acid.-Brands, M., H. P. Sauerwein, M. T. Ackermans, S. Kersten, and M. J. Serlie. Omega-3 long-chain fatty acids strongly induce angiopoietin-like 4 in humans. J. Lipid Res. 2013. 54: 615-621.
Validation of the Diet Quality Index for Adolescents by comparison with biomarkers, nutrient and food intakes: the HELENA study
Vyncke, K. ; Cruz Fernandez, E. ; Fajo-Pascual, M. ; Cuenca-Garcia, M. ; Keyzer, W. de; Gonzalez-Gross, M. ; Moreno, L.A. ; Beghin, L. ; Geelen, A. - \ 2013
The British journal of nutrition 109 (2013). - ISSN 0007-1145 - p. 2067 - 2078.
healthy eating index - fatty-acid-composition - life-style - european adolescents - adipose-tissue - great fat - vitamin-d - nutrition - plasma - blood
Food-based dietary guidelines (FBDG) aim to address the nutritional requirements at population level in order to prevent diseases and promote a healthy lifestyle. Diet quality indices can be used to assess the compliance with these FBDG. The present study aimed to investigate whether the newly developed Diet Quality Index for Adolescents (DQI-A) is a good surrogate measure for adherence to FBDG, and whether adherence to these FBDG effectively leads to better nutrient intakes and nutritional biomarkers in adolescents. Participants included 1804 European adolescents who were recruited in the Healthy Lifestyle in Europe by Nutrition in Adolescence (HELENA) Study. Dietary intake was assessed by two, non-consecutive 24 h recalls. A DQI-A score, considering the components' dietary quality, diversity and equilibrium, was calculated. Associations between the DQI-A and food and nutrient intakes and blood concentration biomarkers were investigated using multilevel regression analysis corrected for centre, age and sex. DQI-A scores were associated with food intake in the expected direction: positive associations with nutrient-dense food items, such as fruits and vegetables, and inverse associations with energy-dense and low-nutritious foods. On the nutrient level, the DQI-A was positively related to the intake of water, fibre and most minerals and vitamins. No association was found between the DQI-A and total fat intake. Furthermore, a positive association was observed with 25-hydroxyvitamin D, holo-transcobalamin and n-3 fatty acid serum levels. The present study has shown good validity of the DQI-A by confirming the expected associations with food and nutrient intakes and some biomarkers in blood
Interaction between dietary content of protein and sodium chloride on milk urea concentration, urinary urea excretion, renal recycling of urea, and urea transfer to the gastrointestinal tract in dairy cows
Spek, J.W. ; Bannink, A. ; Gort, G. ; Hendriks, W.H. ; Dijkstra, J. - \ 2013
Journal of Dairy Science 96 (2013)9. - ISSN 0022-0302 - p. 5734 - 5745.
fed grass-silage - ammonia emissions - nitrogen-excretion - holstein cows - cattle - metabolism - sheep - rumen - plasma - degradability
Dietary protein and salt affect the concentration of milk urea nitrogen (MUN; mg of N/dL) and the relationship between MUN and excretion of urea nitrogen in urine (UUN; g of N/d) of dairy cattle. The aim of the present study was to examine the effects of dietary protein and sodium chloride (NaCl) intake separately, and their interaction, on MUN and UUN, on the relationship between UUN and MUN, on renal recycling of urea, and on urea transfer to the gastrointestinal tract. Twelve second-parity cows (body weight of 645±37kg, 146±29d in milk, and a milk production of 34.0±3.28kg/d), of which 8 were previously fitted with a rumen cannula, were fitted with catheters in the urine bladder and jugular vein. The experiment had a split-plot arrangement with dietary crude protein (CP) content as the main plot factor [116 and 154g of CP/kg of dry matter (DM)] and dietary NaCl content as the subplot factor (3.1 and 13.5g of Na/kg of DM). Cows were fed at 95% of the average ad libitum feed intake of cows receiving the low protein diets. Average MUN and UUN were, respectively, 3.90mg of N/dL and 45g of N/d higher for the high protein diets compared with the low protein diets. Compared with the low NaCl diets, MUN was, on average, 1.74mg of N/dL lower for the high NaCl diets, whereas UUN was unaffected. We found no interaction between dietary content of protein and NaCl on performance characteristics or on MUN, UUN, urine production, and renal clearance characteristics. The creatinine clearance rate was not affected by dietary content of protein and NaCl. Urea transfer to the gastrointestinal tract, expressed as a fraction of plasma urea entry rate, was negatively related to dietary protein, whereas it was not affected by dietary NaCl content. We found no interaction between dietary protein and NaCl content on plasma urea entry rate and gastrointestinal urea entry rate or their ratio. The relationship between MUN and UUN was significantly affected by the class variable dietary NaCl content: UUN=-17.7±7.24 + 10.09±1.016 × MUN + 2.26±0.729 × MUN (for high NaCl); R(2)=0.85. Removal of the MUN × NaCl interaction term lowered the coefficient of determination from 0.85 to 0.77. In conclusion, dietary protein content is positively related to MUN and UUN, whereas dietary NaCl content is negatively correlated to MUN but NaCl content is not related to UUN. We found no interaction between dietary protein and NaCl content on performance, MUN, UUN, or renal urea recycling, nor on plasma urea entry rate and urea transfer to the gastrointestinal tract. For a proper interpretation of the relationship between MUN and UUN, the effect of dietary NaCl should be taken into account, but we found no evidence that the effect of dietary NaCl on MUN is dependent on dietary protein content.
Intake of whole-grain and fiber-rich rye bread versus refined wheat bread does not differentiate intestinal microbiota composition in Finnish adults with metabolic syndrome
Lappi, J. ; Salojärvi, J. ; Kolehmainen, M. ; Mykkänen, H. ; Poutanen, K. ; Vos, W.M. de; Salonen, A. - \ 2013
The Journal of Nutrition 143 (2013)5. - ISSN 0022-3166 - p. 648 - 655.
resistant starch content - insulin sensitivity - gut microbiota - dietary fiber - cereal-fiber - fermentation - plasma - alkylresorcinols - individuals - bacterial
Whole-grain (WG) foods rich in indigestible carbohydrates are thought to modulate the composition of the intestinal microbiota. We investigated in a randomized, parallel, 2-arm 12-wk intervention whether consumption of WG and fiber-rich rye breads compared with refined wheat breads affected the microbiota composition in Finnish individuals aged 60 ± 6 y with metabolic syndrome. Fecal samples from 51 participants (25 males, 26 females) before and after the intervention were processed for the microbiota analysis using a phylogenetic microarray and quantitative polymerase chain reactions targeting the 16S rRNA gene. The intake of whole grains calculated from food records was higher in the group consuming rye breads (75 g) than in that consuming refined wheat breads (4 g; P <0.001), confirmed by fasting plasma alkylrecorsinol concentrations, a biomarker of whole grain intake. The intestinal microbiota composition did not significantly differ between the groups after the intervention. However, we detected a 37% decrease of Bacteroidetes (P <0.05) in parallel to a 53% decrease in the alkylrecorsinol concentration (P <0.001) in the group consuming refined wheat breads. In this group, the abundance of bacteria related to Bacteroides vulgatus, B. plebeius, and Prevotella tannerae decreased, whereas that of bacteria related to Collinsella and members of the Clostridium clusters IV and XI increased. In a multivariate regression analysis, the abundance of Bacteroides spp. was best explained by different fat compounds among dietary variables, whereas the main sugar-converting butyrate-producers were mostly associated with the intake of whole- and refined-grain bread and fiber. Our results indicate that the quality of grains has a minor effect on the intestinal microbiota composition in participants with metabolic syndrome and suggest that the dietary influence on the microbiota involves other dietary components such as fat
Total and high-molecular weight adiponectin and risk of colorectal cancer: the European Prospective Investigation into Cancer and Nutrition Study
Aleksandrova, K. ; Boeing, H. ; Jenab, M. ; Bueno de Mesquita, H.B. ; Jansen, E. ; Duijnhoven, F.J.B. van; Fedirko, V. ; Rinaldi, S. ; Romieu, I. ; Riboli, E. - \ 2012
Carcinogenesis 33 (2012)6. - ISSN 0143-3334 - p. 1211 - 1218.
coronary-heart-disease - metabolic syndrome - adipose-tissue - rectal-cancer - colon-cancer - women - metaanalysis - obesity - plasma - genes
Adiponectin-an adipose tissue-derived protein-may provide a molecular link between obesity and colorectal cancer (CRC), but evidence from large prospective studies is limited. In particular, no epidemiological study explored high-molecular weight (HMW) and non-HMW adiponectin fractions in relation to CRC risk, despite them being hypothesized to have differential biological activities, i.e. regulating insulin sensitivity (HMW adiponectin) versus inflammatory response (non-HMW adiponectin). In a prospective, nested case-control study, we investigated whether prediagnostic serum concentrations of total, HMW and non-HMW adiponectin are associated with risk of CRC, independent of obesity and other known CRC risk factors. A total of 1206 incident cases (755 colon and 451 rectal) were matched to 1206 controls using incidence-density sampling. In conditional logistic regression, adjusted for dietary and lifestyle factors, total adiponectin and non-HMW adiponectin concentrations were inversely associated with risk of CRC [relative risk (RR) comparing highest versus lowest quintile = 0.71, 95% confidence interval (CI) = 0.53-0.95, P(trend) = 0.03 for total adiponectin and RR = 0.45, 95% CI = 0.34-0.61, P(trend) <0.0001 for non-HMW adiponectin]. HMW adiponectin concentrations were not associated with CRC risk (RR = 0.91, 95% CI = 0.68-1.22, P(trend) = 0.55). Non-HMW adiponectin was associated with CRC risk even after adjustment for body mass index and waist circumference (RR = 0.39, 95% CI = 0.26-0.60, P(trend) <0.0001), whereas the association with total adiponectin was no longer significant (RR = 0.81, 95% CI = 0.60-1.09, P(trend) = 0.23). When stratified by cancer site, non-HMW adiponectin was inversely associated with both colon and rectal cancer. These findings suggest an important role of the relative proportion of non-HMW adiponectin in CRC pathogenesis. Future studies are warranted to confirm these results and to elucidate the underlying mechanisms
Bioconjugation of Protein-Repellent Zwitterionic Polymer Brushes Grafted from Silicone Nitride
Nguyen, A.T. ; Baggerman, J. ; Paulusse, J.M.J. ; Zuilhof, H. ; Rijn, C.J.M. van - \ 2012
Langmuir 28 (2012)1. - ISSN 0743-7463 - p. 604 - 610.
biosensor applications - poly(ethylene glycol) - antibody microarrays - surface - adsorption - well - membranes - plasma - immobilization - strategies
A new method for attaching antibodies to protein-repellent zwitterionic polymer brushes aimed at recognizing microorganisms while preventing the nonspecific adsorption of proteins is presented. The poly(sulfobetaine methacrylate) (SBMA) brushes were grafted from a-bromo isobutyryl initiator-functionalized silicon nitride (SixN4, x = 3) surfaces via controlled atom-transfer radical polymerization (ATRP). A trifunctional tris(2-aminoethyl)amine linker was reacted with the terminal alkylbromide of polySBMA chains. N-Hydroxysuccinimide (NHS) functionalization was achieved by reacting the resultant amine-terminated polySBMA brush with bifunctional suberic acid bis(N-hydroxysuccinimide ester). Anti-Salmonella antibodies were subsequently immobilized onto polySBMA-grafted SixN4 surfaces through these NHS linkers. The protein-repellent properties of the polySBMA-grafted surface after antibody attachment were evaluated by exposing the surfaces to Alexa Fluor 488-labeled fibrinogen (FIB) solution (0.1 g·L–1) for 1 h at room temperature. Confocal laser scanning microscopy (CLSM) images revealed the minimal adsorption of FIB onto the antibody-coated polySBMA in comparison with that of antibody-coated epoxide monolayers and also bare SixN4 surfaces. Subsequently, the interaction of antibodies immobilized onto polySBMA with SYTO9-stained Salmonella solution without using blocking solution was examined by CLSM. The fluorescent images showed that antibody-coated polySBMA efficiently captured Salmonella with only low background noise as compared to antibody-coated monolayers lacking the polymer brush. Finally, the antibody-coated polySBMA surfaces were exposed to a mixture of Alexa Fluor 647-labeled FIB and Salmonella without the prior use of a blocking solution to evaluate the ability of the surfaces to capture bacteria while simultaneously repelling proteins. The fluorescent images showed the capture of Salmonella with no adsorption of FIB as compared to antibody-coated epoxide surfaces, demonstrating the potential of the zwitterionic layer in preventing the nonspecific adsorption of the proteins during the detection of bacteria in complex matrices.
Sulphur levels in saliva as an estimation of sulphur status in cattle: a validation study
Dermauw, V. ; Froidmont, E. ; Dijkstra, J. ; Boever, J.L. de; Vyverman, W. ; Debeer, A.E. ; Janssens, G.P.J. - \ 2012
Archives of Animal Nutrition 66 (2012)6. - ISSN 1745-039X - p. 507 - 513.
rumen fluid - sheep - metabolism - sulfate - plasma - roughage - blood - feed - urea - cows
Effective assessment of sulphur (S) status in cattle is important for optimal health, yet remains difficult. Rumen fluid S concentrations are preferred, but difficult to sample under practical conditions. This study aimed to evaluate salivary S concentration as estimator of S status in cattle. Saliva and rumen fluid samples were collected from dairy cows (n = 16) as well as samples of different feedstuffs offered to the animals. The N and S concentrations were determined using the Dumas technique. The average dietary N and S content were calculated as well as N:S ratio of saliva, rumen fluid and diet. Salivary S concentrations could not predict rumen fluid or dietary S concentrations (p > 0.05). The log transformed salivary N:S ratio (x) could predict the rumen fluid N:S ratio (y) with a linear equation of y = 9.83 (±4.59) x + 0.39 (±4.56) (r = 0.497, p = 0.05), but left too much residual variation to serve as reliable predictor. Further research should investigate this relationship in the search for an S status estimator.
A lipidomic analysis approach to evaluate the response to cholesterol-lowering food intake
Szymanska, E. ; Dorsten, F.A. van; Troost, J. ; Paliukhovich, I. ; Velzen, E.J.J. van; Hendriks, M.M.W.B. ; Trautwein, E.A. ; Duynhoven, J.P.M. van; Vreeken, R.J. ; Smilde, A.K. - \ 2012
Metabolomics 8 (2012)5. - ISSN 1573-3882 - p. 894 - 906.
coronary-artery-disease - plant sterols - mass-spectrometry - risk-factor - plasma - sphingomyelin - profiles - intervention - inflammation - metabolism
Plant sterols (PS) are well known to reduce serum levels of total cholesterol and LDL-cholesterol. Lipidomics potentially provides detailed information on a wide range of individual serum lipid metabolites, which may further add to our understanding of the biological effects of PS. In this study, lipidomics analysis was applied to serum samples from a placebo-controlled, parallel human intervention study (n = 97) of 4-week consumption of two PS-enriched, yoghurt drinks differing in fat content (based on 0.1% vs. 1.5% dairy fat). A comprehensive data analysis strategy was developed and implemented to assess and compare effects of two different PS-treatments and placebo treatment. The combination of univariate and multivariate data analysis approaches allowed to show significant effects of PS intake on the serum lipidome, and helped to distinguish them from fat content and non-specific effects. The PS-enriched 0.1% dairy fat yoghurt drink had a stronger impact on the lipidome than the 1.5% dairy fat yoghurt drink, despite similar LDL-cholesterol lowering effects. The PS-enriched 0.1% dairy fat yoghurt drink reduced levels of several sphingomyelins which correlated well with the reduction in LDL-cholesterol and can be explained by co-localization of sphingomyelins and cholesterol on the surface of LDL lipoprotein. Statistically significant reductions in serum levels of two lysophosphatidylcholines (LPC(16:1), LPC(20:1)) and cholesteryl arachidonate may suggest reduced inflammation and atherogenic potential. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s11306-011-0384-2) contains supplementary material, which is available to authorized users.
Angiopoietin-like protein 4 is differentially regulated by glococorticoids and insulin in vitro and in vivo in healthy humans
Raalte, D.H. ; Brands, M. ; Serlie, M.J. ; Mudde, C.M. ; Stienstra, R. ; Sauerwein, H.P. ; Kersten, A.H. ; Diamant, M. - \ 2012
Experimental and Clinical Endocrinologie and Diabetes 120 (2012)10. - ISSN 0947-7349 - p. 598 - 603.
lipoprotein-lipase - fatty-acids - adipose-tissue - target gene - plasma - angptl4 - glucose - hyperlipidemia - mice
Objective: Angiopoietin-like protein 4 (Angptl4) is a circulating inhibitor of plasma triglyceride clearance via inhibition of lipoprotein lipase. The aim of the present study was to examine the regulation of Angptl4 by glucocorticoids and insulin in vivo in humans, since these factors regulate Angptl4 expression in vitro. Research design and methods: In a randomized, placebo-controlled, double-blind, dose-response intervention study, 32 healthy males (age: 22 +/- 3 years; BMI 22.4 +/- 1.7 kg m(-2)) were allocated to prednisolone 30 mg once daily (n = 12), prednisolone 7.5 mg once daily (n = 12), or placebo (n = 8) for 2 weeks. Angptl4 levels and lipid metabolism were measured before and at 2 weeks of treatment, in the fasted state and during a 2-step hyperinsulinemic clamp. Additionally, human hepatoma cells were treated with dexamethasone and/or insulin. Results: Compared to placebo, prednisolone treatment tended to lower fasting Angptl4 levels (P = 0.073), raised fasting insulin levels (P = 0.0004) and decreased fasting nonesterified fatty acid concentrations (NEFA) (P = 0.017). Insulin infusion reduced Angptl4 levels by 6 % (plasma insulin similar to 200 pmol/l, P = 0.006) and 22 % (plasma insulin similar to 600 pmol/l, P <0.0001), which was attenuated by prednisolone treatment (P = 0.03). Prednisolone 7.5 mg and 30 mg dose-dependently decreased insulin-mediated suppression of lipolysis (by 11 +/- 5 % and 34 +/- 6 % respectively). Prednisolone 30 mg enhanced fasting triglyceride levels (P = 0.028). Plasma Angptl4 was not related to prednisolone-induced changes in lipid metabolism. In human hepatoma cells, dexamethasone increased Angptl4 mRNA expression and protein secretion, whereas insulin had the opposite effect. Conclusions: Insulin lowers plasma Angptl4 levels in humans by lowering NEFA and by inhibiting Angptl4 expression and release. Glucocorticoids counteract insulin-mediated suppression of Angptl4.
Tea consumption and incidence of type 2 diabetes in Europe: the EPIC-InterAct case-cohort study
Feskens, E.J.M. ; Groenendijk-van Woudenbergh, G.J. ; Kuijsten, A. - \ 2012
PLoS ONE 7 (2012)5. - ISSN 1932-6203 - 8 p.
black tea - green tea - oolong tea - coffee - risk - obesity - plasma - cancer - milk - metaanalysis
Background In previous meta-analyses, tea consumption has been associated with lower incidence of type 2 diabetes. It is unclear, however, if tea is associated inversely over the entire range of intake. Therefore, we investigated the association between tea consumption and incidence of type 2 diabetes in a European population. Methodology/Principal Findings The EPIC-InterAct case-cohort study was conducted in 26 centers in 8 European countries and consists of a total of 12,403 incident type 2 diabetes cases and a stratified subcohort of 16,835 individuals from a total cohort of 340,234 participants with 3.99 million person-years of follow-up. Country-specific Hazard Ratios (HR) for incidence of type 2 diabetes were obtained after adjustment for lifestyle and dietary factors using a Cox regression adapted for a case-cohort design. Subsequently, country-specific HR were combined using a random effects meta-analysis. Tea consumption was studied as categorical variable (0, >0-
Tolerance and safety evaluation of N, N-dimethylglycine, a naturally occurring organic compound, as a feed additive in broiler diets
Kalmar, I.D. ; Verstegen, M.W.A. ; Maenner, K. ; Zentek, J. ; Meulemans, G. ; Janssens, G.P.J. - \ 2012
The British journal of nutrition 107 (2012)11. - ISSN 0007-1145 - p. 1635 - 1644.
n,n dimethylglycine - performance - betaine - nutrition - chickens - carcass - stress - plasma - foods - fat
N, N-dimethylglycine (DMG) is a tertiary amino acid that naturally occurs as an intermediate metabolite in choline-to-glycine metabolism. The objective of the present trial was to evaluate tolerance, safety and bioaccumulation of dietary DMG in broilers when supplemented at 1 g and 10 g Na-DMG/kg. A feeding trial was conducted using 480 1-d-old broiler chicks that were randomly allocated to twenty-four pens and fed one of three test diets added with 0, 1 or 10 g Na-DMG/kg during a 39 d growth period. Production performance was recorded to assess tolerance and efficacy of the supplement. At the end of the trial, toxicity was evaluated by means of haematology, plasma biochemistry and histopathology of liver, kidney and heart (n 12), whereas bioaccumulation was assessed on breast meat, liver, blood, kidney and adipose tissue (n 8). Carcass traits were similar between the control and 1 g Na-DMG/kg feed groups (P>0·05), but the feed:gain ratio was significantly improved at 1 g Na-DMG/kg feed compared with the control or the 10-fold dose (P = 0·008). Histological examinations showed no pathological effects and results of haematology and plasma biochemistry revealed similar values between the test groups (P>0·05). Bioaccumulation occurred at the 10-fold dose, but the resulting DMG content in breast meat was comparable with, for instance, wheat bran and much lower than uncooked spinach. In conclusion, DMG at 1 g Na-DMG/kg improved the feed:gain ratio in broilers without DMG being accumulated in consumer parts. Furthermore, dietary supplementation with DMG up to 10 g Na-DMG/kg did not induce toxicity or impaired performance in broilers.
Assessment of liquid chromatography-tandem mass spectrometry approaches for the analysis of ceftiofur metabolites in poultry muscle
Berendsen, B.J.A. ; Stolker, A.A.M. ; Nielen, M.W.F. - \ 2012
Food Additives & Contaminants. Pt. A, Chemistry, Analysis, Control, Exposure & Risk Assessment 29 (2012)2. - ISSN 1944-0049 - p. 197 - 207.
beta-lactam antibiotics - escherichia-coli - bacterial pathogens - kidney tissue - bovine - swine - plasma - desfuroylceftiofur - cattle - milk
The use of cephalosporin antibiotics in veterinary practice is likely to play an important role in the development of ß-lactam-resistant bacteria. To detect off-label cephalosporin antibiotic usage, an analytical method is needed that, besides the native compound, also detects their active metabolites. In this paper, the applicability of three approaches for the quantitative analysis of ceftiofur using LC–MS/MS is assessed, viz. (A) analysis of ceftiofur, desfuroylceftiofur and/or desfuroylceftiofur cystein disulfide, (B) derivatisation of ceftiofur metabolites to desfuroylceftiofur acetamide and (C) chemical hydrolysis using ammonia, to produce a marker compound for ceftiofur. We found that approach A was not suited for quantitative analysis of total ceftiofur concentration or for effectively detecting off-label use of ceftiofur. Approach B resulted in adequate quantitative results, but was considered a single compound method because it depends on cleavage of a thioester group, which is present in only a limited number of cephalosporin antibiotics. Approach C showed adequate quantitative results but, in contrast to approach B, it is applicable to a range of cephalosporin antibiotics. Therefore, it is applicable as a broad quantitative screening of cephalosporin compounds in poultry tissue samples to indicate off-label use of cephalosporins in poultry breeding. Based on this study, it was concluded that approach C is the most suitable to detect off-label use of a range of cephalosporin antibiotics.
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