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The influence of microbial metabolites on human intestinal epithelial cells and macrophages in vitro

van Nuenen, M.H.M.C. (author), de Ligt, R.A.F. (author), Doornbos, R.P. (author), van der Woude, J.C.J. (author), Kuipers, E.J. (author), Venema, K. (author), TNO Kwaliteit van Leven (author)

Microbial metabolites may influence the metabolic integrity of intestinal epithelial cells and induce mucosal immune responses. Therefore, we investigated the effects of the microbial metabolites butyrate, iso-valerate, and ammonium on Caco-2 cells and macrophages. Barrier functioning was determined by measuring transepithelial electrical...

article 2005

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The FEMA GRAS assessment of benzyl derivatives used as flavor ingredients

Adams, T.B. (author), Cohen, S.M. (author), Doull, J. (author), Feron, V.J. (author), Goodman, J.I. (author), Marnett, L.J. (author), Munro, I.C. (author), Portoghese, P.S. (author), Smith, R.L. (author), Waddell, W.J. (author), Wagner, B.M. (author), TNO Kwaliteit van Leven (author)

This publication is the eighth in a series of safety evaluations performed by the Expert Panel of the Flavor and Extract Manufacturers Association (FEMA). In 1993, the panel initiated a comprehensive program to re-evaluate the safety of more than 1700 GRAS flavoring substances under conditions of intended use. Elements that are fundamental to...

article 2005

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Low bone mineral density and bone mineral content are associated with low cobalamin status in adolescents

Dhonukshe-Rutten, R.A.M. (author), van Dusseldorp, M. (author), Schneede, J. (author), de Groot, L.C.P.G.M. (author), van Staveren, W.A. (author), TNO Kwaliteit van Leven (author)

Background: Cobalamin deficiency is prevalent in vegetarians and has been associated with increased risk of osteoporosis. Aim of the study: To examine the association between cobalamin status and bone mineral density in adolescents formerly fed a macrobiotic diet and in their counterparts. Methods: In this cross-sectional study bone mineral...

article 2005

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Unravelling the multiple effects of lactic acid stress on Lactobacillus plantarum by transcription profiling

Pieterse, B. (author), Leer, R.J. (author), Schuren, F.H.J. (author), van der Werf, M.J. (author), TNO Kwaliteit van Leven (author)

The organic acid lactate is the predominant fermentation product of Lactobacillus plantarum. The undissociated form of this organic acid is a strong growth inhibitor for the organism. Different theories have been postulated to explain the inhibitory effects of lactic acid: (i) toxicity arising from the dissipation of the membrane potential, (ii)...

article 2005

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Effects of coffee consumption on fasting blood glucose and insulin concentrations: Randomized controlled trials in healthy volunteers

van Dam, R.M. (author), Pasman, W.J. (author), Verhoef, P. (author), TNO Voeding (author)

article 2004

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Dietary serine and cystine attenuate the homocysteine-raising effect of dietary methionine: A randomized crossover trial in humans

Verhoef, P. (author), Steenge, G.R. (author), Boelsma, E. (author), van Vliet, T. (author), Olthof, M.R. (author), Katan, M.B. (author), TNO Voeding (author)

Background: A high plasma total homocysteine (tHcy) concentration is a risk factor for cardiovascular disease. The increase in tHcy induced by methionine, the sole dietary precursor of homocysteine, might be modulated by other amino acids present in dietary proteins. Objectives: Our objectives were to compare the postprandial effect of free and...

article 2004

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Relevance of Ara h1, Ara h2 and Ara h3 in peanut-allergic patients, as determined by immunoglobulin E Western blotting, basophil-histamine release and intracutaneous testing: Ara h2 is the most important peanut allergen

Koppelman, S.J. (author), Wensing, M. (author), Ertmann, M. (author), Knulst, A.C. (author), Knol, E.F. (author), TNO Voeding (author)

Background: A number of allergenic proteins in peanut has been described and the relative importance of these allergens is yet to be determined. Objectives: We have investigated the relevance of previously identified peanut allergens in well-characterized peanut-allergic patients by in vitro, ex vivo and in vivo assays. Methods: Thirty-two adult...

article 2004

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Calcium measurements in living filamentous fungi expressing codon-optimized aequorin

Nelson, G. (author), Kozlova-Zwinderman, O. (author), Collis, A.J. (author), Knight, M.R. (author), Fincham, J.R.S. (author), Stanger, C.P. (author), Renwick, A. (author), Hessing, J.G.M. (author), Punt, P.J. (author), van den Hondel, C.A.M.J.J. (author), Read, N.D. (author), TNO Voeding Centraal Instituut voor Voedingsonderzoek TNO (author)

Calcium signalling is little understood in filamentous fungi largely because easy and routine methods for calcium measurement in living hyphae have previously been unavailable. We have developed the recombinant aequorin method for this purpose. High levels of aequorin expression were obtained in Neurospora crassa, Aspergillus niger and...

article 2004

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Clot penetration and fibrin binding of amediplase, a chimeric plasminogen activator (K2tu-PA)

Rijken, D.C. (author), Barrett-Bergshoeff, M.M. (author), Jie, A.F.H. (author), Criscuoli, M. (author), Sakharov, D.V. (author), Gaubius Instituut TNO (author)

Amediplase (K2tu-PA) is a hybrid plasminogen activator, consisting of the kringle 2 domain of alteplase and the protease domain of urokinase. The objective of this study was to determine the in vitro clot penetration of amediplase in relation to its fibrin binding and to compare the properties with those of alteplase. The clot lysis activity of...

article 2004

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Block of neuronal nicotinic acetylcholine receptors by organophosphate insecticides

Smulders, C.J.G.M. (author), Bueters, T.J.H. (author), Vailati, S. (author), van Kleef, R.G.D.M. (author), Vijvergberg, H.P.M. (author)

Chronic and acute exposure to organophosphate (OP) pesticides may lead to persistent neurological and neurobehavioral effects, which cannot be explained by acetylcholinesterase (AChE) inhibition alone. It is suggested that other brain proteins are involved. Effects of commonly used organophosphate pesticides on rat neuronal α4β2 nicotinic...

article 2004

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Low-level exposure of guinea pigs and marmosets to sarin vapour in air: Lowest-observable-adverse-effect level (LOAEL) for miosis

van Helden, H.P.M. (author), Trap, H.C. (author), Kuijpers, W.C. (author), Oostdijk, J.P. (author), Benschop, H.P. (author), Langenberg, J.P. (author), Prins Maurits Laboratorium TNO (author)

The purpose of this pilot study was to indicate, for low-level exposure of conscious guinea pigs and marmoset monkeys to sarin vapour in air, the lowest-observable-adverse-effect level (LOAEL) of sarin for miosis. This is the concentration × time (C·t) value (t = 5 h) of exposure at which miosis becomes significant. The ratio of pupil and iris...

article 2004

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Retrospective detection of exposure to nerve agents: Analysis of phosphofluoridates originating from fluoride-induced rectivation of phospylated BuChE

Prins Maurits Laboratorium TNO (author), van der Schans, M.J. (author), Polhuijs, M. (author), van Dijk, C. (author), Degenhardt, C.E.A.M. (author), Pleijsier, K. (author), Langenberg, J.P. (author), Benschop, H.P. (author)

The utility was explored of a new approach to detect retrospectively exposure to nerve agents by means of conversion of the inhibitor moiety bound to the active site of the enzyme BuChE in plasma with fluoride ions into a phosphofluoridate which is subsequently analyzed by means of gas chromatography (GC). This quantifies ≥0.01% inhibition of...

article 2004

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Protein Adsorption at Air-Water Interfaces: A Combination of Details

de Jongh, H.H.J. (author), Kosters, H.A. (author), Kudryashova, E. (author), Meinders, M.B.J. (author), Trofimova, D. (author), Wierenga, P.A. (author), TNO Voeding (author)

Using a variety of spectroscopic techniques, a number of molecular functionalities have been studied in relation to the adsorption process of proteins to air-water interfaces. While ellipsometry and drop tensiometry are used to derive information on adsorbed amount and exerted surface pressure, external reflection circular dichroism, infrared,...

article 2004

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MMP profile in paired serum and synovial fluid samples of patients with rheumatoid arthritis

Gaubius Instituut TNO (author), Tchetverikov, I. (author), Ronday, H.K. (author), van El, B. (author), Kiers, G.H. (author), Verzijl, N. (author), TeKoppele, J.M. (author), Huizinga, T.W.J. (author), de Groot, J. (author), Hanemaaijer, R. (author)

Objective: To analyse matrix metalloproteinases (MMPs) and tissue inhibitor-1 of MMPs (TIMP-1) levels in the systemic circulation and synovial fluid (SF) of patients with RA and to compare these levels with inflammatory and collagen degradation markers. Methods: ProMMP-1, -2, -3, -8, -9, TIMP-1, levels of MMP/ α2-macroglobulin complexes, and...

article 2004

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Aminopeptidase inhibitor bestatin stimulates microvascular endothelial cell invasion in a fibrin matrix

van Hensbergen, Y. (author), Broxterman, H.J. (author), Peters, E. (author), Rana, S. (author), Elderkamp, Y.W. (author), van Hinsbergh, V.W.M. (author), Koolwijk, P. (author), Gaubius Instituut TNO (author)

The aminopeptidase inhibitor bestatin has been shown to have anti-angiogenic effects in a number of model systems. These effects are thought to result from inhibition of CD13 activity. Because tumor angiogenesis can evolve in a fibrin-rich stroma matrix we have studied for the first time the effects of bestatin on microvascular endothelial...

article 2003

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How accurate and safe is the diagnosis of hazelnut allergy by means of commercial skin prick test reagents?

Akkerdaas, J.H. (author), Wensing, M. (author), Knulst, A.C. (author), Krebitz, M. (author), Breiteneder, H. (author), de Vries, S. (author), Penninks, A.H. (author), Aalberse, R.C. (author), Hefle, S.L. (author), van Ree, R. (author)

Background: Allergy to tree nuts, like hazelnuts, ranks among the most frequently observed food allergies. These allergies can start at early childhood and are, in contrast to other food allergies, not always outgrown by the patient. Tree nut allergy is frequently associated with severe reactions. Diagnosis partially relies on in vivo testing by...

article 2003

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Evaluating the migration of ingredients from active packaging and development of dedicated methods: A study of two iron-based oxygen absorbers

López-Cervantes, L. (author), Sánchez-Machado, D.I. (author), Pastorelli, S. (author), Rijk, R. (author), Paseiro-Losada, P. (author), TNO Voeding (author)

The behaviour of two commercial oxygen-scavenging products with respect to migration of active ingredients into foodstuffs was investigated. Migrants were identified, and by using appropriate analytical methods, migration was determined in a variety of liquid, solid or gelled food simulants and foods. Simulants were chosen to cover a range of...

article 2003

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Removal of two polycyclic musks in sewage treatment plants: Freely dissolved and total concentrations

Artola-Garicano, E. (author), Borkent, I. (author), Hermens, J.L.M. (author), Vaes, W.H.J. (author)

In the current study, the removal of slowly degradable hydrophobic chemicals in sewage treatment plants (STPs) has been evaluated with emphasis on the combination of free and total concentration data. Free and total concentrations of two polycyclic musks were determined in each compartment of four STPs. The free concentration of the polycyclic...

article 2003

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Comparison of on-line flow-cell and off-line solvent-elimination interfaces for size-exclusion chromatography and Fourier-transform infrared spectroscopy in polymer analysis

Kok, S.J. (author), Wold, C.A. (author), Hankemeier, Th. (author), Schoenmakers, P.J. (author)

Two commercial liquid chromatography-Fourier-transform infrared spectroscopy interfaces (LC-FTIR), viz. a flow cell and a solvent-elimination interface have been assessed for use in size-exclusion chromatography (SEC) with respect to their chromatographic integrity (i.e. peak asymmetry, chromatographic resolution), quantitative and qualitative...

article 2003

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Biosensors and multiple mycotoxin analysis

van der Gaag, B. (author), Spath, S. (author), Dietrich, H. (author), Stigter, E. (author), Boonzaaijer, G. (author), van Osenbruggen, T. (author), Koopal, K. (author)

An immunochemical biosensor assay for the detection of multiple mycotoxins in a sample is described.The inhibition assay is designed to measure four different mycotoxins in a single measurement, following extraction, sample clean-up and incubation with an appropriate cocktail of anti-mycotoxin antibodies.The different mycotoxins could be...

article 2003