A Meckel's diverticulum presenting as pyogenic liver abscesses.

Meckel's diverticula are the most common congenital malformation of the small intestine. The condition is rarely symptomatic and is usually an incidental finding during surgery. Bleeding in children and obstruction in adults are the most common symptomatic presentations.

Mechanical force-activated phospholipase D is mediated by Galpha12/13-Rho and calmodulin-dependent kinase in renal epithelial cells.

The renal glomerulus, the site of plasma ultrafiltration, is exposed to mechanical force in vivo arising from capillary blood pressure and fluid flow. Studies of cultured podocytes demonstrate that they respond to stretch by altering the structure of the actin cytoskeleton, but the mechanisms by which physical force triggers this architectural change and the signaling pathways that lead to generation of second messengers are not defined. In the present study, we found that in renal epithelial cells [podocytes and Madin-Darby canine kidney (MDCK) cells], application of mechanical force to the cell surface through fibronectin-coated ferric beads and exposure of the cells to magnetic force lead to Rho translocation and actin cytoskeleton reorganization.

Role of ceramide in Ca2+-sensing receptor-induced apoptosis.

Increased extracellular Ca(2+) ([Ca(2+)](o)) can damage tissues, but the molecular mechanisms by which this occurs are poorly defined. Using HEK 293 cell lines that stably overexpress the Ca(2+)-sensing receptor (CaR), a G protein-coupled receptor, we demonstrate that activation of the CaR leads to apoptosis, which was determined by nuclear condensation, DNA fragmentation, caspase-3 activation, and increased cytosolic cytochrome c. This CaR-induced apoptotic pathway is initiated by CaR-induced accumulation of ceramide which plays an important role in inducing cell death signals by distinct G protein-independent signaling pathways.