The immunological synapse: a focal point for endocytosis and exocytosis

There are many different cells in the immune system. To mount an effective immune response, they need to communicate with each other. One way in which this is done is by the formation of immunological synapses between cells. Recent developments show that the immune synapse serves as a focal point for exocytosis and endocytosis, directed by centrosomal docking at the plasma membrane. In this respect, formation of the immunological synapse bears striking similarities to cilia formation and cytokinesis. These intriguing observations suggest that the centrosome may play a conserved role in designating a specialized area of membrane for localized endocytosis and exocytosis

A change of colloid from hydroxyethyl starch to gelatin does not reduce rate of renal failure or mortality in surgical critical care patients: Results of a retrospective cohort study.

PURPOSE Hydroxyethyl starch (HES) may compromise renal function in critically ill patients. As an alternative, gelatin (GEL) was suggested. This study investigated whether GEL (4%) may have advantages over HES (6%, 130/0.4) with respect to acute renal failure (ARF), length of intensive care unit /hospital stay, and 30-day mortality and evaluated dose-dependent effects. MATERIAL AND METHODS We performed a retrospective cohort analysis of 1522 surgical intensive care patients in a single university hospital where HES was changed to GEL in June 2006. The year before, 515 patients received HES; the year after, 540 patients received GEL. Within both years, 497 patients received crystalloids (CRY) only. Fluid therapy was performed upon clinical judgment and did not follow a study protocol. RESULTS There was no difference in ARF between HES and GEL (P=.292), but ARF was more frequent in both colloid cohorts compared with CRY (HES/GEL vs CRY, P<.05). Mortality and maximum daily dose of both HES (r=0.93) and GEL (r=0.93) were significantly correlated, but mortality and total amount of CRY or total fluid intake were not significantly correlated. Cumulative amounts of fluids given were significantly higher in both colloid groups compared with CRY only, and GEL was given in higher doses than HES. In both colloid cohorts, the need for renal replacement therapy and 30-day mortality were significantly higher, and intensive care unit and hospital stay was longer, compared with CRY. CONCLUSIONS A change of colloid from HES to GEL did not reduce the rate of ARF or mortality in surgical critical care patients. Both colloids appear to have dose-dependent effects on renal function