Pathways modelling

The pathway model makes a number of key predictions, including (a) a substantial role for hydrogen bond mediation of tunnelling, (b) a difference in mediation characteristics as a function of secondary and tertiary stmcture, (c) an intrinsically nonexponential decay of rate witlr distance, and (d) patlrway specific Trot and cold spots for electron transfer. These predictions have been tested extensively. The most systematic and critical tests are provided witlr mtlrenium-modified proteins, where a syntlretic ET active group cair be attached to the protein aird tire rate of ET via a specific medium stmcture cair be probed (figure C3.2.5). 

Sugano, K., N. Takata, M. Machida, K. Saitoh, and K. Terada. Prediction of passive intestinal absorption using bio-mimetic artificial membrane permeation assay and the paracellular pathway model, Int. J. Pharm. 2002, 241, 241-251... 

Stice, E., Ziemba, C., Margolis, ]., Flick, P. (1996). The dual pathway model differentiates bulimics, subclinical bulimics, and controls Testing the continuity hypothesis. Behavior Therapy, 27, 531-550. 

Lee AJ, King JR, Rogers TG (1996) A multiple-pathway model for the diffusion of drugs in skin. IMA J Math Appl Med Biol 13 127-150. 

Aaberg RL, Peloquin RA, Strenge DL, et al. 1983. Aquatic-pathway model to predict the fate of phenolic compounds. Prepared for the U S. Dept of Energy, Pacific Northwest Laboratory, Richland, WA. Available through NTIS, order No. DE 83011074, Springfield, VA. 

Figure 10. Kleitz s reaction pathway model for solid-state gas-diffusion electrodes. Traditionally, losses in reversible work at an electrochemical interface can be described as a series of contiguous drops in electrical state along a current pathway, for example. A—E—B. However, if charge transfer at point E is limited by the availability of a neutral electroactive intermediate (in this case ad (b) sorbed oxygen at the interface), a thermodynamic (Nernstian) step in electrical state [d/j) develops, related to the displacement in concentration of that intermediate from equilibrium. In this way it is possible for irreversibilities along a current-independent pathway (in this case formation and transport of electroactive oxygen) to manifest themselves as electrical resistance. This type of chemical valve , as Kleitz calls it, may also involve a significant reservoir of intermediates that appears as a capacitance in transient measurements such as impedance. Portions of this image are adapted from ref 46. (Adapted with permission from ref 46. Copyright 1993 Rise National Laboratory, Denmark.)...

There are no recent improvement in the paracellular pathway permeation models, probably because there is no specific in vitro or in vivo system to measure the paracellular pathway contribution. The paracellular pathway models was constructed using very hydrophilic compounds [107] or subtracting the contribution of transcel-lular pathway from the total passive permeation [78]. Paracellular pathway was modeled as permeation through a charged aqueous pore. A combination of size sieving function and electric field function was found to model the paracellular pathway [78, 87, 88]. 

All three chloroacetic acids (chloroacetic acid [MCA], dichloroacetic acid [DCA], and trichloroacetic acid [TCA]) are naturally occurring (7), with TCA being identified in the environment most frequently (reviews (278, 405 108)). However, these chlorinated acetic acids also have anthropogenic sources. The major source of natural TCA appears to be the enzymatic (chloroperoxidase) or abiotic degradation of humic and fulvic acids, which ultimately leads to chloroform and TCA. Early studies (409) and subsequent work confirm both a biogenic and an abiotic pathway. Model experiments with soil humic and fulvic acids, chloroperoxidase, chloride, and hydrogen peroxide show the formation of TCA, chloroform, and other chlorinated compounds (317, 410-412). Other studies reveal an abiotic source of TCA (412, 413). 

Tezel, A., A. Sens, and S. Mitragotri. 2003. Description of transdermal transport of hydrophilic solutes during low-frequency sonophoresis based on a modified porous pathway model. J Pharm Sci 92 381. 

Fig. 2 Pathways modeled for aerobic and anaerobic degradation of PCE and TCE at Dover Air Force Base (after [19])...

Wnt Signaling, Volume 2 Pathway Models, edited by Elizabeth Vincan, 2008 468. Wnt Signaling, Volume 1 Pathway Methods and MammalianModels, edited by Elizabeth Vincan, 2008... 

Figure 4 Distance dependence of driving-force-optimized electron tunneling times in Ru-labeled P. aeruginosa azurin. The sohd line is the distance decay predicted by the tunneling-pathway model for ET along an ideal 8-strand ( 8 = 1.0 A ). The dashed line is the best fit to the data fi =. A ) ...

Pathway models related to specific cell responses... 

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