Colin McCann

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Neutrophil recruitment to inflammation sites purportedly depends on sequential waves of chemoattractants. Current models propose that leukotriene B(4) (LTB(4)), a secondary chemoattractant secreted by neutrophils in response to primary chemoattractants such as formyl peptides, is important in initiating the inflammation process. In this study we demonstrate(More)
We observe and quantify wave-like characteristics of amoeboid migration. Using the amoeba Dictyostelium discoideum, a model system for the study of chemotaxis, we demonstrate that cell shape changes in a wave-like manner. Cells have regions of high boundary curvature that propagate from the leading edge toward the back, usually along alternating sides of(More)
Collective migration is a key feature of the social amoebae Dictyostelium discoideum, where the binding of chemoattractants leads to the production and secretion of additional chemoattractant and the relay of the signal to neighboring cells. This then guides cells to migrate collectively in a head-to-tail fashion. We used mutants that were defective in(More)
During cell migration, cell-substrate binding is required for pseudopod anchoring to move the cell forward, yet the interactions with the substrate must be sufficiently weak to allow parts of the cell to de-adhere in a controlled manner during typical protrusion/retraction cycles. Mammalian cells actively control cell-substrate binding and respond to(More)
Neutrophils express a variety of collagen receptors at their surface, yet their functional significance remains unclear. Although integrins are essential for neutrophil adhesion and migration on 2-dimensional (2D) surfaces, neutrophils can compensate for the absence of integrins in 3-dimensional (3D) lattices. In contrast, we demonstrate that the inhibition(More)
This study has redesigned the Rey 15-item Visual Memory Test (1964) by introducing more complex figures and by increasing internal logic and pattern redundancy. Standardized administrative procedures and rules for a simple qualitative scoring system were established. Performance on the original Rey continued to be significantly contaminated by ability(More)
We apply linear stability theory and perform perturbation studies to better characterize, and to generate new experimental predictions from, a model of chemotactic gradient sensing in eukaryotic cells. The model uses reaction-diffusion equations to describe 3(') phosphoinositide signaling and its regulation at the plasma membrane. It demonstrates a range of(More)
This study aims to elucidate the effects of the logical form and geometrical content of an argument on spatial deductive reasoning. We will investigate the effects of these factors by comparing the opposing predictions made by the Formal Rules theory and the Mental Models theory of spatial deductive reasoning. We will also elucidate the effects of(More)
Title of Document: EFFECTS OF MEMBRANE-BINDING PEPTIDES ON THE PHYSICAL PROPERTIES OF LIPID BILAYERS Beatriz Eugenia Burrola Gabilondo Doctor of Philosophy, 2010 Directed By: Professor Wolfgang Losert Department of Physics The physics of lipid bilayers has been studied for varying lipid and protein constituents. The effects of molecules that transiently(More)