Lipid mediators

Autotrophy A unique form of metabolism foimd only in bacteria. Inorganic compounds (e.g., NH3, N02-, S2, and Fe2+) are oxidized directly (without using sunlight) to yield energy. This metabolic mode also requires energy for C02 reduction, like photosynthesis, but no lipid-mediated processes are involved. This metabolic mode has also been called chemotrophy, chemoautotrophy, or chemolithotrophy. 

Baumgartner and coworkers [145,146] study lipid-protein interactions in lipid bilayers. The lipids are modeled as chains of hard spheres with heads tethered to two virtual surfaces, representing the two sides of the bilayer. Within this model, Baumgartner [145] has investigated the influence of membrane curvature on the conformations of a long embedded chain (a protein ). He predicts that the protein spontaneously localizes on the inner side of the membrane, due to the larger fluctuations of lipid density there. Sintes and Baumgartner [146] have calculated the lipid-mediated interactions between cylindrical inclusions ( proteins ). Apart from the... 

CC, and one CX3C and XC chemokine receptors have been cloned so far [2]. Receptor binding initiates a cascade of intracellular events mediated by the receptor-associated heterotrimeric G-proteins. These G-protein subunits trigger various effector enzymes that lead to the activation not only of chemotaxis but also to a wide range of fimctions in different leukocytes such as an increase in the respiratory burst, degranulation, phagocytosis, and lipid mediator synthesis. 

Inflammation. Figure 1 Sequence of events in the recruitment of leukocytes in postcapillary venules adjacent to injured tissue. At the site of lesion, diverse reactive substances stimulate the endothelium to produce inflammatory cytokines, chemoattractants and other inflammatory mediators. The cytokine-activated endothelium expresses adhesion molecules that lead to the low affinity interactions between leukocytes and endothelium, which is mediated by selectins and described as rolling. Subsequently integrins mediate the firm adhesion of leukocytes, which allows emigration of the cells from venules into the interstitial compartment. Activated mast cells, PMNs and macrophages secrete cytokines (TNFa), lipid mediators (LTB4) and other inflammatory players (histamine, NO). 

Alber S., Huang L., Watkins S., Li S. Lipid-mediated delivery of peptide nucleic acids to pulmonary endothelium. 

Preformed Mediators Synthesized by HHMC 101 Lipid Mediators de novo Synthesized by HHMC... 

Prescott SM et al Platelet-activating factor and related lipid mediators. Annu Rev Biochem 2000 69 4l9. 

Endogenous Sources of ROS in the 8. Oxidant Stress and Lipid Mediators 223... 

Randolph GJ. Dendritic cell migration to lymph nodes cytokines, chemokines, and lipid mediators. Semin Immunol 2001 13(5) 267-274. 

Urade, Y., el al. (2002). Iipocalin-type and hematopoietic prostaglandin D synthases as a novel example of functional convergence. Prostaglandins Other Lipid Mediators 68-9, 375 82. 

Volume 187. Arachidonate Related Lipid Mediators Edited by Robert C. Murphy and Frank A. Fitzpatrick... 

Bennett, M.J., Aberle A.M., Balasubramaniam R.P., Malone, J.G., Malone, R.W., and Nantz, M.H., Cationic lipid-mediated gene delivery to murine lung correlation of lipid hydration with in vivo transfection activity, Journal of Medicinal Chemistry, 1997, 40, 4069 1078. 

Several enveloped viruses, and some physical gene transfer techniques such as electroporation, deliver the nucleic acid into the cell by direct crossing of the cell membrane. Lipid-based, enveloped systems can do this by a physiological, selfsealing membrane fusion process, avoiding physical damage of the cell membrane. For cationic lipid-mediated delivery of siRNA, most material is taken up by endo-cytotic processes. Recently, direct transfer into the cytosol has been demonstrated to be the bioactive delivery principle for certain siRNA lipid formulations [151]. 

Lu JJ, Langer R, Chen J (2009) A novel mechanism is involved in cationic lipid-mediated functional siRNA delivery. Mol Pharmaceutics 6 763-771... 

L Tiano, A Kantar, G Falcioni, GP Littarru, V Cherubini, R Fiorini. Prostaglandins Other Lipid Mediat 62 351-366, 2000. 

Once apoptosis is triggered, a stereotyped sequence of premitochondrial events occurs that executes the cell death process. In many cases proteins and/or lipid mediators that induce changes in mitochondrial membrane permeability and calcium regulation are produced or activated. For example, the pro-apoptotic Bcl-2 family members Bax, Bad and Bid may associate with the mitochondrial membrane and modify its permeability. Membrane-derived lipid mediators such as ceramide and 4-hydroxynonenal can also induce mitochondrial membrane alterations that are critical for the execution of apoptosis. 

Poddar-Sarkar M. and Brahmachary, R.L. (1997) Putative semiochemicals in the African Cheetah Acinonyx jubatus). J.Lipid Mediator and Cell Signalling 15, 285-287. 

F. Snyder, PAF and Related Lipid Mediators (Plenum Press, New York, 1987). 

P. Sirois, M. Harczy, C. Robidoux, P. Borgeat and P. Braquet, in Lipid Mediators in Immunology of Burn and Sepsis, eds. M. Paubert-Braquet, P. Braquet, R. Demling, R. Fletcher and M. Foegh (Plenum Press, New York, 1987) pp. 187-196. 

Poddar-Sarkar M (1996) J Lipid Mediators Cell Signaling 15 89... 

A thin film of oil-like material was visible after 28 d on the exterior surfaces of the SPMD membrane. Analysis of this film indicated that the triolein impurities, oleic acid and methyl oleate, were the major constituents. This external lipid film (Petty et al., 1993) appeared to contain imbibed particulates. Although the film was removed from the SPMDs by solvent rinsing and analyzed separately, some lipid-mediated desorption of particle-associated PCBs and subsequent diffusion into the SPMD may have occurred prior to solvent-removal of the film. This observation suggests the potential for SPMD concentrations to reflect both vapor phase concentrations and to a lesser extent, lipid-extracted particulate-associated residues (see Section 3.9.2.). Unfortunately, concentrations of more chlorinated congeners in particulates collected on GFFs from the NIOSH method were often below quantitation limits, because only a small volume of air was sampled (1 m ) using this active method. 

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