Searched for: subject:"Biological%5C+Transport"
(1 - 20 of 36)

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Treijtel, N. (author), Eijkeren, J.C.H.v. (author), Nijmeijer, S. (author), van der Greef de - Sandt, I.C.J. (author), Freidig, A.P. (author), TNO Kwaliteit van Leven (author)
The metabolism and active transport of ritonavir and saquinavir were studied using sandwich-cultured rat hepatoyctes and rat liver microsomes. For ritonavir four comparable metabolites were observed in the sandwich-culture and in microsomes. For saquinavir eight metabolites were observed in sandwich-culture and 14 different metabolites in...
article 2009
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Schutte, M.E. (author), Boersma, M.G. (author), Verhallen, D.A.M. (author), Groten, J.P. (author), Rietjens, I.M.C.M. (author), TNO Kwaliteit van Leven (author)
This study describes and kinetically models the effect of flavonoid mixtures on PhIP transport through Caco-2 monolayers. Previously it was shown that quercetin, luteolin, naringenin and myricetin increase the apical to basolateral PhIP transport in Caco-2 monolayers. In this study, apigenin was shown to exert a similar effect with an apparent...
article 2008
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Schutte, M.E. (author), Alink, G.M. (author), Freidig, A.P. (author), Spenkelink, B. (author), Vaessen, J.C.H. (author), van de Sandt, J.J.M. (author), Groten, J.P. (author), Rietjens, I.M.C.M. (author), TNO Kwaliteit van Leven (author), KvL (author)
This study investigates whether the previous observation that quercetin increases the transport of PhIP through Caco-2 monolayers in vitro could be confirmed in an in vivo rat model. Co-administration of 1.45 μmol PhIP/kg bw and 30 μmol quercetin/kg bw significantly increased the blood AUC(0-8 h) of PhIP in rats to 131 ± 14% of the AUC(0-8 h)...
article 2008
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Halter, D. (author), Neumann, S. (author), van Dijk, S.M. (author), Wolthoorn, J. (author), de Mazière, A.M. (author), Vieira, O.V. (author), Mattjus, P. (author), Klumperman, J. (author), van Meer, G. (author), Sprong, H. (author), TNO Kwaliteit van Leven (author)
Glycosphingolipids are controlled by the spatial organization of their metabolism and by transport specificity. Using immunoelectron microscopy, we localize to the Golgi stack the glycosyltransferases that produce glucosylceramide (GlcCer), lactosylceramide (LacCer), and GM3. GlcCer is synthesized on the cytosolic side and must translocate...
article 2007
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Schutte, M.E. (author), Freidig, A.P. (author), van de Sandt, J.J.M. (author), Alink, G.M. (author), Rietjens, I.M.C.M. (author), Groten, J.P. (author), TNO Kwaliteit van Leven (author)
The present study describes the effect of different flavonoids on the absorption of the pro-carcinogen PhIP through Caco-2 monolayers and the development of an in silico model describing this process taking into account passive diffusion and active transport of PhIP. Various flavonoids stimulated the apical to basolateral PhIP transport. Using...
article 2006
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Brand, W. (author), Schutte, M.E. (author), Williamson, G. (author), van Zanden, J.J. (author), Cnubben, N.H.P. (author), Groten, J.P. (author), van Bladeren, P.J. (author), Rietjens, I.M.C.M. (author), TNO Kwaliteit van Leven (author)
The transcellular transport of ingested food ingredients across the intestinal epithelial barrier is an important factor determining bioavailability upon oral intake. This transcellular transport of many chemicals, food ingredients, drugs or toxic compounds over the intestinal epithelium can be highly dependent on the activity of membrane bound...
article 2006
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Rensen, P.C.N. (author), Havekes, L.M. (author), TNO Kwaliteit van Leven (author)
Chemicals / CAS: 2 methylpropanethioic acid s [2 [1 (2 ethylbutyl)cyclohexylcarboxamido]phenyl] ester, 211513-37-0; atorvastatin, 134523-00-5, 134523-03-8; nicotinic acid, 54-86-4, 59-67-6; torcetrapib, 262352-17-0; Carrier Proteins; CETP protein, human; Cholesterol Ester Transfer Proteins; Cholesterol Esters; Cholesterol, HDL; Glycoproteins;...
article 2006
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Cnubben, N.H. (author), Wortelboer, H.M. (author), van Zanden, J.J. (author), Rietjens, I.M. (author), van Bladeren, P.J. (author), TNO Kwaliteit van Leven (author)
Membrane transport proteins belonging to the ATP-binding cassette (ABC) family of transport proteins play a central role in the defence of organisms against toxic compounds, including anticancer drugs. However, for compounds that are designed to display a toxic effect, this defence system diminishes their effectiveness. This is typically the...
article 2005
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Verwei, M. (author), van den Berg, H. (author), Havenaar, R. (author), Groten, J.P. (author), TNO Defensie en Veiligheid TNO Kwaliteit van Leven (author)
Background: Milk products are a potential matrix for fortification with synthetic folic acid or natural 5-methyltetrahydrofolate (5-CH 3-H4folate) to enhance the daily folate intake. In milk, folate occurs bound to folatebinding proteins (FBP). Our previous studies with an in vitro gastrointestinal model showed that 70% of the initial FBP...
article 2005
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Wortelboer, H.M. (author), Usta, M. (author), van Zanden, J.J. (author), van Bladeren, P.J. (author), Rietjens, I.M.C.M. (author), Cnubben, N.H.P. (author), TNO Kwaliteit van Leven (author)
To study the possible interplay between glutathione metabolism of and MRP inhibition by thiol reactive compounds, the interactions of a series of α,β-unsaturated carbonyl compounds with multidrug resistance proteins 1 and 2 (MRP1/ABCC1 and MRP2/ABCC2) were studied. α,β-Unsaturated carbonyl compounds react with glutathione, and therefore either...
article 2005
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van Zanden, J.J. (author), Geraets, L. (author), Wortelboer, H.M. (author), van Bladeren, P.J. (author), Rietjens, I.M.C.M. (author), Cnubben, N.H.P. (author), TNO Voeding (author)
The objective of this study was to investigate the structural requirements necessary for inhibition of glutathione S-transferase P1-1 (GSTP1-1) and GS-X pump (MRP1 and MRP2) activity by structurally related flavonoids, in GSTP1-1 transfected MCF7 cells (pMTG5). The results reveal that GSTP1-1 activity in MCF7 pMTG5 cells can be inhibited by some...
article 2004
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Out, R. (author), Kruijt, J.K. (author), Rensen, P.C.N. (author), Hildebrand, R.B. (author), de Vos, P. (author), van Eck, M. (author), van Berkel, T.J.C. (author), TNO Preventie en Gezondheid (author)
The function of scavenger receptor class B type I (SR-BI) in mediating the selective uptake of high density lipoprotein (HDL) cholesterol esters is well established. However, the potential role of SR-BI in chylomicron and chylomicron remnant metabolism is largely unknown. In the present investigation, we report that the cell association of 160...
article 2004
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Sierksma, A. (author), Vermunt, S.H.F. (author), Lankhuizen, I.M. (author), van der Gaag, M.S. (author), Scheek, L.M. (author), Grobbee, D.E. (author), van Tol, A. (author), Hendriks, H.F.J. (author), TNO Voeding (author)
Background: Alcohol consumption is associated with increased high-density lipoprotein (HDL) cholesterol levels. One of the main antiatherogenic functions of HDL is reverse cholesterol transport. Three early steps of reverse cholesterol transport are (1) cellular cholesterol efflux, (2) plasma cholesterol esterification (EST), and (3) cholesteryl...
article 2004
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Post, S.M. (author), de Crom, R. (author), van Haperen, R. (author), van Tol, A. (author), Princen, H.M.G. (author), Gaubius Instituut TNO (author)
Objective - HDL plays a key role in protection against development of atherosclerosis by promoting reverse cholesterol transport from peripheral tissues to the liver for secretion into bile. Phospholipid transfer protein (PLTP) promotes the transfer of phospholipids between lipoproteins and modulates HDL size and composition, thereby having a...
article 2003
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Sakharov, D.V. (author), Jie, A.F.H. (author), Filippov, D.V. (author), Bekkers, M.E.A. (author), van Boom, J.H. (author), Rijken, D.C. (author), Gaubius Instituut TNO (author)
Extracellular matrix (ECM) of tissues, vascular tissue in particular, contains a high concentration of negatively charged glycosaminoglycans (GAGs), which are involved in the regulation of cell motility, cell proliferation and the regulation of enzyme activities. Previously, we have shown that the vascular ECM is capable of binding an extremely...
article 2003
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Faassen, F. (author), Kelder, J. (author), Lenders, J. (author), Onderwater, R. (author), Vromans, H. (author)
Purpose. The purpose of this work was to study the relevant physicochemical properties for the absorption of steroids. Methods. Various physicochemical properties of steroids were calculated (molecular weight, ClogP, static polar surface area [PSA], etc.). Within this series of steroids, different pharmacological groups were defined. Based on...
article 2003
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van der Gaag, M.S. (author), van Tol, A. (author), Vermunt, S.H.F. (author), Scheek, L.M. (author), Schaafsma, G. (author), Hendriks, H.F.J. (author), Centraal Instituut voor Voedingsonderzoek TNO (author)
Alcohol consumption is associated with increased HDL cholesterol levels, which may indicate stimulated reverse cholesterol transport. The mechanism is, however, not known. The aim of this study was to evaluate the effects of alcohol consumption on the first two steps of the reverse cholesterol pathway: cellular cholesterol efflux and plasma...
article 2001
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Rensen, P.C.N. (author), Jong, M.C. (author), van Vark, L.C. (author), van der Boom, H. (author), Hendriks, W.L. (author), van Berkel, T.J.C. (author), Biessen, E.A.L. (author), Havekes, L.M. (author), Gaubius instituut TNO (author)
Apolipoprotein E (apoE) is an important determinant for the uptake of triglyceride-rich lipoproteins and emulsions by the liver, but the intracellular pathway of apoE following particle internalization is poorly defined. In the present study, we investigated whether retroendocytosis is a unique feature of apoE as compared with apoB by studying...
article 2000
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Chaillou, S. (author), Pouwels, P.H. (author), Postma, P.W. (author), Centraal Instituut voor Voedingsonderzoek TNO (author)
We have identified and characterized the D-xylose transport system of Lactobacillus pentosus. Uptake of D-xylose was not driven by the proton motive force generated by malolactic fermentation and required D-xylose metabolism. The kinetics of D-xylose transport were indicative of a low- affinity facilitated-diffusion system with an apparent K(m)...
article 1999
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Sitter, T. (author), Toet, K. (author), Quax, P. (author), Kooistra, T. (author), Gaubius instituut TNO (author)
Background. Human mesothelial cells (HMCs) have an important role in maintaining an adequately functioning fibrinolytic system in the peritoneal cavity by secreting the fibrinolytic enzymes tissue-type and urokinase-type plasminogen activator (t-PA and u-PA), as well as a specific PA inhibitor, PA inhibitor type 1 (PAI-1). In this study, we...
article 1999
Searched for: subject:"Biological%5C+Transport"
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