Compounds known to modulate P-glycoprotein (P-gp) activity were evaluated in cell monolayers expressing P-gp for their effects on the secretory transport of P-gp substrates paclitaxel, vinblastine, and digoxin. Paclitaxel has been proposed to selectively interact with a binding site on P-gp that is distinct from the vinblastine and digoxin-binding site. Using Madin-Darby canine kidney (MDCK)-mu...

We have examined the expression of P-glycoprotein (P-gp) in adult T-cell leukemia (ATL) samples from 25 patients. Based on immunoblotting with a monoclonal antibody against P-gp, C219, 8 of 20 ATL patients were P-gp positive at the initial presentation. All 6 patients at the relapsed stage were P-gp positive, and refractory to chemotherapy. The expression of MDR1 mRNA in P-gp-positive ATL cells...

Rivaroxaban, an oral, direct factor Xa inhibitor, has a dual mode of elimination in humans, with two-thirds metabolized by the liver and one-third renally excreted unchanged. P-glycoprotein (P-gp) is known to be involved in the absorption, distribution, and excretion of drugs. To investigate whether rivaroxaban is a substrate of P-gp, the bidirectional flux of rivaroxaban across Caco-2, wild-ty...

Let M be a complete non-compact manifold satisfying the volume doubling condition, with index N and reverse n, n≤N, both for large balls. Assume Gaussian upper bound heat kernel, an L2-Poincaré inequality outside compact set. If 2<n, then we show that p∈(2,n), (Rp): Lp-boundedness of Riesz transform, (Gp): gradient semigroup, (RHp): Lp-Hölder harmonic functions, are equivalent to each other. Ou...

P-glycoprotein (P-gp) mediates efflux of xenobiotics and bacterial toxins from the intestinal mucosa into the lumen. Dysregulation of P-gp has been implicated in inflammatory bowel disease. Certain probiotics have been shown to be effective in treating inflammatory bowel disease. However, direct effects of probiotics on P-gp are not known. Current studies examined the effects of Lactobacilli on...

Antrodia cinnamomea is a traditional healthy food that has been demonstrated to possess anti-inflammatory, antioxidative, and anticacer effects. The purpose of this study was to evaluate whether the ethanolic extract of A. cinnamomea (EEAC) can affect the efflux function of P-glycoprotein (P-gp) and the effect of ABCB1 genetic variants on the interaction between EEAC and P-gp. To investigate th...

  Conflicting results have been reported on segmental differences in expression of P-glycoprotein (P-gp) along the small intestine of animals and humans. In this study, we investigated P-gp mRNA and protein levels within each of nine segments of rat small intestine. In addition, P-gp activity in each segment was evaluated in terms of permeability of rhodamine123 (Rho123), a typical P-gp substra...

Previously, we reported that repeated oral administration of etoposide (ETP) increases P-glycoprotein (P-gp) expression in association with activation of ezrin/radixin/moesin (ERM) in the small intestine. Radixin has recently attracted attention for its critical role in the plasma membrane localization of certain drug transporters including P-gp by working as a scaffold protein. However, there ...

The effect of P-glycoprotein (P-gp, ABCB1, MDR1) expression on cell resistance to nilotinib was studied in human leukaemia cells. We used K562/Dox cells overexpressing P-gp and their variants (subclones) with a gradually decreased P-gp expression. These subclones were established by stable transfection of K562/Dox cells with a plasmid vector expressing shRNA targeting the ABCB1 gene. Functional...

Our concern lies in solving the following convex optimization problem: GP : minimizex cTx s.t. Ax = b x ∈ P, where P is a closed convex subset of the n-dimensional vector space X. We bound the complexity of computing an almost-optimal solution of GP in terms of natural geometry-based measures of the feasible region and the level-set of almost-optimal solutions, relative to a given reference poi...