The static and dynamical properties of L-lysine adsorbed onto a hydroxylated quartz surface were modeled by using semiempirical quantum mechanics and force field techniques. Both semiempirical and force field calculations indicate that a strong interaction occurs between the -protonated amino group of L-lysine with the surface. Furthermore, the amino acid molecule has a preferred end-on orientation, with the -protonated amino group pointing toward the surface. The statistical analysis of the system trajectories reveals that the relatively ordered water-shell structure of the amino acid molecule in the "bulk" solution is broken when the molecule approaches the surface because of the reciprocal perturbation of the molecule and surface solvation shells.

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We developed a nanosized perfluorocarbon-based system with incorporated paramagnetic Gd(III) chelates, able to generate a quantitative 19F MRI signal, while in parallel capable of modulating the 1H MRI signal in...

Interferon (IFN)-gamma, interleukin (IL)-10, IL-6, and tumor necrosis factor (TNF)-alpha were significantly increased in sera from Sicilian patients with acute boutonneuse fever (BF) compared with those of healthy controls. IFN-gamma levels dropped sharply within the second week after infection. IL-6, IL-10, and TNF-alpha levels gradually declined; in convalescent patients only were they in the normal range. In contrast, peripheral blood mononuclear cells (PBMC) stimulated in vitro with phytohemagglutinin (PHA) produced low levels of IL-10 and IFN-gamma in acute BF that were compatible with the reduction in the levels of CD4+, CD4+/CD45RO+, and CD4+/CD45RA+ cells. In vitro production of TNF-alpha and IL-6 from PBMC stimulated with PHA was not significantly modified during the various phases of the infection compared with control PBMC, which could be due to the persistence of high levels of CD14+ monocytes compensating for the decrease in CD20+ B cells.