Stephen R. Clark

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It has been known for many years that neutrophils and platelets participate in the pathogenesis of severe sepsis, but the inter-relationship between these players is completely unknown. We report several cellular events that led to enhanced trapping of bacteria in blood vessels: platelet TLR4 detected TLR4 ligands in blood and induced platelet binding to(More)
To study the mechanisms involved in leukocyte recruitment induced by local bacterial infection within the CNS, we used intravital microscopy to visualize the interaction between leukocytes and the microvasculature in the brain. First, we showed that intracerebroventricular injection of LPS could cause significant rolling and adhesion of leukocytes in the(More)
In this study, murine peritoneal macrophages from naïve lavage were found to generate four phospholipids that contain 12-hydroxyeicosatetraenoic acid (12-HETE). They comprise three plasmalogen and one diacyl phosphatidylethanolamines (PEs) (16:0p, 18:1p, 18:0p, and 18:0a at sn-1) and are absent in macrophages from 12/15-lipoxygenase (12/15-LOX)-deficient(More)
Precursor LC/MS/MS of esterified HETEs. Lipid extracts were separated on a C18 Luna(2), 3 !m, 150 mm x 2 mm column (Phenomenex) using a gradient of 0 to 100 % B over 10 min, then held at 100 % B for 30 min (A, methanol:acetonitrile:water, 60:20:20 containing 1mM ammonium acetate, B, methanol with 1mM ammonium acetate) at 200 !l/min, then analyzed online(More)
Platelet activation represents a key event in normal hemostasis as well as during platelet plug formation related to thrombosis. Nitro-fatty acids are novel endogenously produced signaling mediators exerting pluripotent anti-inflammatory actions in cells and tissues. We have recently shown that nitroarachidonic acid inhibits thromboxane synthesis during(More)
5-Lipoxygenase (5-LOX) plays key roles in infection and allergic responses. Herein, four 5-LOX-derived lipids comprising 5-hydroxyeicosatetraenoic acid (HETE) attached to phospholipids (PLs), either phosphatidylethanolamine (PE) or phosphatidylcholine (18:0p/5-HETE-PE, 18:1p/5-HETE-PE, 16:0p/5-HETE-PE, and 16:0a/5-HETE-PC), were identified in primary human(More)
OBJECTIVE To investigate the role of death receptor 3 (DR-3) and its ligand tumor necrosis factor-like molecule 1A (TL1A) in the early stages of inflammatory arthritis. METHODS Antigen-induced arthritis (AIA) was generated in C57BL/6 mice deficient in the DR-3 gene (DR3(-/-) ) and their DR3(+/+) (wild-type) littermates by priming and intraarticular(More)
We investigate the influence of a Bose-Einstein condensate (BEC) on the properties of immersed impurity atoms, which are trapped in an optical lattice. Assuming a weak coupling of the impurity atoms to the BEC, we derive a quantum master equation for the lattice system. In the special case of fixed impurities with two internal states the atoms represent a(More)
In some cases the state of a quantum system with a large number of subsystems can be approximated efficiently by the density-matrix renormalization group, which makes use of redundancies in the description of the state. Here we show that the achievable efficiency can be much better when performing density-matrix renormalization group calculations in the(More)
Nitration of unsaturated fatty acids such as linoleate by NO-derived reactive species forms novel derivatives (including nitrolinoleate [LNO2]) that can stimulate smooth muscle relaxation and block platelet activation by either NO/cGMP or cAMP-dependent mechanisms. Here, LNO2 was observed to inhibit human neutrophil function. LNO2, but not linoleic acid or(More)