Compound C represents a potentially new therapeutic agent in treating and preventing occlusive vascular disease.”
“Sliding friction between crystal lattices and the physics of cold ion traps are so far non-overlapping fields. Two

sliding lattices may either stick and show static friction or slip with dynamic friction; cold ions are known to form static chains, helices or clusters, depending on the trapping conditions. Here we show, based on simulations, that much could be learnt about friction PF-6463922 in vitro by sliding, through, for example, an electric field, the trapped ion chains over a corrugated potential. Unlike infinite chains, in which the theoretically predicted Aubry transition to free sliding may take place, trapped chains are always pinned. Yet, a properly defined static friction still vanishes Aubry-like at a symmetric-asymmetric structural transition, found for decreasing corrugation in both straight and zig-zag trapped chains. Dynamic friction selleck chemicals is also accessible in ringdown oscillations of the ion trap. Long theorized static and dynamic one-dimensional friction phenomena could thus become accessible in future cold ion tribology.”
“Deposition of amyloid beta (A beta) containing plaques in the brain is one of the neuropathological hallmarks of Alzheimer’s disease (AD). It has been

suggested that modulation of neuronal activity may alter A beta production in the brain. We postulate that these changes in A beta production are due to changes in the rate-limiting step of A beta generation, APP cleavage by gamma-secretase.

By combining biochemical approaches with fluorescence lifetime imaging microscopy, we found that neuronal inhibition decreases endogenous find more APP and PSI interactions, which correlates with reduced A beta production. By contrast, neuronal activation had a two-phase effect: it initially enhanced APP-PS1 interaction leading to increased A beta production, which followed by a decrease in the APP and PS1 proximity/interaction. Accordingly, treatment of neurons with naturally secreted A beta isolated from AD brain or with synthetic A beta resulted in reduced APP and PS1 proximity. Moreover, applying low concentration of A beta(42) to cultured neurons inhibited de novo A beta synthesis. These data provide evidence that neuronal activity regulates endogenous APP-PSI interactions, and suggest a model of a product-enzyme negative feedback. Thus, under normal physiological conditions A beta may impact its own production by modifying gamma-secretase cleavage of APP. Disruption of this negative modulation may cause A beta overproduction leading to neurotoxicity. (C) 2012 Elsevier Inc. All rights reserved.”
“Many of the regulatory processes occurring during plant embryogenesis are still unknown. Relatively few cells are involved, and they are embedded within maternal tissues, making this developmental phase difficult to study.