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The article presents a user interface for web browsing on mobile phones that is optimized for interaction with web 2.0 social media. It uses a combination of tags, tag clouds, virtual buttons and thumbnail images. The interface is designed to overcome the inherent limitations of a handheld device, such as a smart phone, which does not allow for a large keyboard or visual display area. It avoids the hierarchical menu-based design of traditional mobile phones. A test involving undergraduate students is described, which indicated that the interface made it easier to browse or upload user-generated content.

The secretory transport of the H(2)-antagonists, ranitidine and famotidine, across Caco-2 cell monolayers was found to be a saturable process. Both drugs exhibited greater permeability in the basolateral (BL) to apical (AP) direction than in the AP to BL direction, indicating apically directed secretion; BL to AP transport was inhibited by P-glycoprotein (P-gp) inhibitors verapamil and cyclosporin A. The cellular uptake of ranitidine across the BL membrane was saturable and temperature dependent, indicative of carrier-mediated transport. The K(m) and V(max) for the uptake process were estimated to be 66.9 mM and 20.9 nmol/mg of protein/min, respectively. The uptake of [(14)C]ranitidine across the BL membrane was inhibited by unlabeled ranitidine and structurally diverse organic cations. The tetraethylammonium (TEA)-sensitive organic cation transporters are not involved in the uptake of ranitidine and famotidine across the BL membrane of Caco-2. This conclusion was based on the evidence that functionally active TEA-sensitive organic cation transporters did not exist in the BL membranes of the Caco-2 cells, whereas the functionally active TEA-sensitive organic cation transporter(s) in LLC-PK(1) cells did not contribute to the transport of ranitidine or famotidine across the cell monolayers. Thus, we conclude that the secretory transport of ranitidine and famotidine across Caco-2 cell monolayers is mediated by 1) a carrier in the BL membrane that is distinct from the TEA-sensitive organic cation transporter(s) and 2) P-gp in the apical membrane.