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G Protein-Coupled Receptors (GPCRs) are the most targeted group of proteins for the development of therapeutic drugs. Until the last decade, structural information about this family of membrane proteins was relatively scarce, and their mechanisms of ligand binding and signal transduction were modeled on the assumption that GPCRs existed and functioned as monomeric entities. New crystal structures of native and engineered GPCRs, together with important biochemical and biophysical data that reveal structural details of the activation mechanism(s) of this receptor family, provide a valuable framework to improve dynamic molecular models of GPCRs with the ultimate goal of elucidating their allostery and functional selectivity. Since the dynamic movements of single GPCR protomers are likely to be affected by the presence of neighboring interacting subunits, oligomeric arrangements should be taken into account to improve the predictive ability of computer-assisted structural models of GPCRs for effective use in drug design.

We present an ab initiocalculation of the line shape of the photoabsorption spectrum of Na8and Na+9clusters at zero temperature, including the polarization effect driven by the electron-plasmon coupling, together with the electron-phonon coupling. The electron-plasmon coupling is found to yield a significant lowering of the energy centroid of the plasmons, whereas the main effect the electron-phonon coupling has is to smooth the spectrum.

Modern formulation bases the appropriate selection of excipients on technological determinations. Due to negative effects on mechanical and biopharmaceutical properties of tablets, the amount of lubricant to be used requires optimization. Lubricants are difficult to evaluate in terms of effectiveness. The number of references existing in literature on this topic substantiates the necessity still remaining in pharmaceutics for lubricant testing (1, 2, 3, 4, 5).