The matricellular "cysteine-rich protein 61" is released from activated platelets and increased in the circulation during experimentally induced sepsis.

Sepsis and sepsis-induced organ dysfunction remain lethal and common conditions among intensive care patients. Accumulating evidence suggests that the matricellular Cyr61/CCN1 (cysteine-rich, angiogenic-inducer, 61) protein is involved in the regulation of inflammatory responses and possesses organ-protective capabilities in diseases of an inflammatory etiology. However, its regulation in sepsis remains largely unexplored. The present study provides a comprehensive description of CCN1 regulation in the circulation and vital organs during experimentally induced sepsis with developing organ dysfunction. Female CD-1 mice served as baseline controls or were subjected to cecal ligation and puncture (CLP) for 18 to 96 h, and CCN1 regulation was analyzed in selected organs and in the circulation. A 5-, 5-, and 3-fold increases in circulating CCN1 protein were observed at 18, 48, and 96 h after CLP, respectively. Hepatic and pulmonary CCN1 mRNA expression was down-regulated by 80%, 60%, and 55% and 85%, 80%, and 65% at 18, 48, and 96 h after CLP and undetectable in circulating white blood cells. To identify a potential source for the circulating protein, mouse and human platelets were explored and revealed to contain CCN1. Human platelets were stimulated by thrombin and a specific PAR1 agonist (SFLLRN) in vitro. Both agonists induced an instant CCN1 release, and the effect of SFLLRN was blocked by the specific antagonist RWJ56110. The current study demonstrates that experimental sepsis is associated with a robust increase in circulating CCN1 protein levels and a paradoxical downregulation of CCN1 mRNA expression in vital organs. It provides evidence that CCN1 is released from activated platelets, suggesting that platelets constitute a novel source for CCN1 release to the circulation during sepsis.

Towards two-dimensional metallic behavior at LaAlO3/SrTiO3 interfaces.

Using a low-temperature conductive-tip atomic force microscope in cross-section geometry we have characterized the local transport properties of the metallic electron gas that forms at the interface between LaAlO3 and SrTiO3. At low temperature, we find that the carriers do not spread away from the interface but are confined within approximately 10 nm, just like at room temperature. Simulations taking into account both the large temperature and electric-field dependence of the permittivity of SrTiO3 predict a confinement over a few nm for sheet carrier densities larger than approximately 6x10(13) cm(-2). We discuss the experimental and simulations results in terms of a multiband carrier system. Remarkably, the Fermi wavelength estimated from Hall measurements is approximately 16 nm, indicating that the electron gas in on the verge of two dimensionality.

Effect of liquid distortion and aperture shape on the quality of bubble chamber photographs.

When a plane wave that has passed through a turbulent liquid is brought to a focus by a lens, the image moves erratically. The distortion produced by the liquid is here defined as the root-mean-square distance of the centroid of the diffraction pattern from its mean position. Expressions have been obtained that enable one to calculate this quantity as a function of liquid conditions and the results have been used to judge the effectiveness of using annular apertures in the photography of propane bubble chamber events.