Modulation of surface

As stated earlier, activation of endothelial cells by pro-inflammatory stimuli leads to the expression of cell adhesion molecules and cytokines such as IL-6 and IL-8. The expression and hence modulation of surface expressed adhesion molecules by e.g. targeted delivery of inhibitors of NFkB, can be measured using flow cytometric analysis or whole cell ELISA techniques. Cytokine production can be measured in the supernatant of cultured cells or in biological fluids. Furthermore, competitive or quantitative RT-PCR analysis of mRNA levels of cell adhesion molecules or cytokines, allows the transcriptional activity of the genes of interest to be estimated. 

The discussion of the origin of the signal helps in the classification of conduc-tomettic sensors. Chemiresistors (Fig. 8.1a) are normally measured in DC mode and the capacitances in the equivalent circuit can be neglected. Thus, the analytical information is obtained from the modulation of surface (Rs), contact (Rc), or... 

Another interesting modification of glass surfaces was introduced by Beier and Hoheisel.23 They synthesized a flexible, dendritic linker system that enables covalent immobilization of oligonucleotides and PNAs with high loading capacity in a controlled manner. This method facilitates the modulation of surface properties such as hydrophobicity and charge. The synthesis of the linker system involves two consecutive reactions an acylation of surface-bound amine groups with acid chloride (4-nitrophenyl-chloroformate or acryloylchloride) and subsequent reaction with an amine. A bis-amine results in a linker system, while a polyamine produces a dendritic structure (Fig. 14.3). Because polyamines possess primary and secondary amine... 

Despite of hybridization with biological ligands, the general strategy for optimizing protein adsorption on biomaterial surfaces relies on chemical or physicochemical modulation of surface hydrophilicity [38,39]. The common approach is surface immobilization of hydrophilic polymers like polyethylene glycol [PEG] or polysaccharides. Four categories of surface-modification pathways have been developed ... 

Fig. 8.13 (a) Potential dependence of the phenomenological rate constant k,r derived for mechanism I. Note that for a two step mechanism, this rate constant contains terms associated with surface recombination, so that it is not the true rate constant for electron transfer. The influence of the modulation of potential due to surface charging is shown, (b) Potential dependence of the phenomenological rate constant k,t for case /. The influence of the dynamic modulation of surface potential by accumulated reaction intermediates is... 

Gan, Q., Wang,T., Cochrane, C., and McCarron, P. (2005), Modulation of surface charge, particle size and morphological properties of chitosan-TPP nanoparticles intended for gene delivery, Colloids Surf. B. Biointerfaces, 44(2-3), 65-73. 

The cyclonic eddy-like structures, similar to eddies 10 and 15 (Figure la) and 9-11 (Figure 4), are typical of the Kuroshio Current area east of Taiwan. They have been detected on many ERS-1/2 SAR images however, their position is variable. These eddies were observed due to their radar contrast against the background and/or the presence of definite structures (narrow spiral lines), resulting from the modulation of surface roughness by variable currents. Filamentary slicks were much less common here to favour their detection. Estimates of the current velocity for two eddies obtained by the analysis of the oil spill displacements were found to be 0.07-0.08 ms"1 and 0.3 ms"1. 

Fig. 17b. Potential dependence of the phenomenological rate constant k for case I [89]. The influence of the dynamic modulation of surface potential by accumulated reaction intermediates is shown.

Because we believe TNF and NO are important in lesion formation in MS, we have become interested in the modulation of surface and soluble TNF-Rs in the CNS. Here, we have chosen to examine the paradigms previously established in immune cells in human glial cell cultures in an effort to relate the interrelationship and regulation of these entities. 

Aloisi, F., Borsellino, G., Samoggia, P., Testa, U., Chelucci, C., Russo, G., Peschle, C., and Levi, G. (1992a). Astrocyte cultures from human embryonic brain Characterization and modulation of surface molecules by inflammatory cytokines. /. Neurosci. Res. 32, 294-506. 

Yu HF, Shishido A, Ikeda T. 2008b. Subwavelength modulation of surface relief and refractive index in pre irradiated liquid crystalline pol5mer films. Appl Phys Lett 92 103117/1 103117/3. 

Darhuber AA, Troian SM (2005) Principles of microfluidic actuation by modulation of surface stresses. Annu Rev Fluid Mech 37(l) 425-455... 

Daihuber AA, Valentino JP, Davis JM, Troian SM, Wagner S (2003) Microfluidic actuatirai by modulation of surface stresses. Appl Phys Lett 82(4) 657-659... 

Burg KJ, Allan JM, Roweton SL and Shalaby SW, Modulation of surface and bulk properties of biomedical polymers , Anno/s of the New York Academy of Sciences, 831,1997, pp 217-222. 

A. A. Darhuber, Microfluidic actuation by modulation of surface stresses. Appl. Phys. Lett., 2003, 82, 657-659. 

Fig. 10. Subwavelength modulation of surface relief and refractive index in LC polymer films.

Yu, H. F. Shishido, A. Ikeda, T. (2008a). Subwavelength Modulation of Surface Relief and Refractive Index in Pre-Irradiated Liquid-Crystalline Polymer Films. Appl. Phys. Lett, 2008, 92,103117/1-103117/3. 

FAcrr Collagcmous dtnnains interrupted by Modulators of surface properties ... 

The modulation of surface electron density at Hg implied by Eq. (10) is manifested not only through changes of surface tension, but may be indirectly observed in the change of relative specular reflectivity (McIntyre and Peck, 1972 Gottesfeld et al., 1973) with electrode potential at Hg and at other metals under conditions not restricted to liquid state surfaces. 

Elbert J, Mersini J, VUbrandt N, LedCTle C, Kraska M, Gallei M, Stuehn B, Plenio H, Rehahn M (2013) Reversible activity modulation of surface-attached grubbs second generation type catalysts using redox-responsive polymers. Macromolecules 46 4255—4267... 

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