Internet Electronic Conference of Molecular Design 2004, November 23 – December 6 Abstract Motivation. Chelatable methacrylates with phosphate groups, such as MDP, have been used as tooth-bonding agents in dentistry [1, 2]. MDP has shown acceptable pulp response and clinical performance. However, the effect of MDP on biological membranes remains unknown. Liposomes have been employed in model sy...

The effects of surfactant-associated protein A (SPA) on lipid adsorption to the air-water interface and accumulation of dipalmitoylphosphatidylcholine (DPPC) in the surface region were investigated at 37%. Dispersions used were bovine pulmonary lipid extract surfactant with or without neutral lipid (NL). Lipid adsorption was examined with the Wilhelmy plate technique and DPPC accumulation by mo...

Pulmonary surfactant is a lipid:protein complex containing dipalmitoyl-phosphatidylcholine (DPPC) as the major component. Recent studies indicate adsorbed surfactant films consist of a surface monolayer and a monolayer-associated reservoir. It has been hypothesized that the monolayer and its functionally contiguous reservoir may be enriched in DPPC relative to bulk phase surfactant. We investig...

We measured the transbilayer diffusion of 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) in large unilamellar vesicles, in both the gel (Lβ') and fluid (Lα) phases. The choline resonance of headgroup-protiated DPPC exchanged into the outer leaflet of headgroup-deuterated DPPC-d13 vesicles was monitored using 1H NMR spectroscopy, coupled with the addition of a paramagnetic shift reagent. Thi...

Due to the inhalation of airborne particles containing bacterial lipopolysaccharide (LPS), these molecules might incorporate into the 1,2-dipalmitoylphosphatidylcholine (DPPC)-rich monolayer and interact with surfactant protein A (SP-A), the major surfactant protein component involved in host defense. In this study, epifluorescence microscopy combined with a surface balance was used to examine ...

Pulmonary surfactant protein A (SP-A) is an oligomeric glycoprotein that binds dipalmitoylphosphatidylcholine (DPPC). Interactions of rat SP-A and recombinant SP-As with pure and binary monolayers of DPPC and cholesterol were studied using a rhomboid surface balance at 37 degrees C. A marked inflection at equilibrium surface tension (23 mN/m) in surface tension-area isotherm of a pure DPPC film...

The study of asymmetric lipid bilayers is of a crucial importance due to the great number of biological process in which they are involved such as exocytosis, intracellular fusion processes, phospholipid-protein interactions, and signal transduction pathway. In addition, the loss of this asymmetry is a hallmark of the early stages of apoptosis. In this regard, a model of an asymmetric lipid bil...

The interaction of L-phenylalanine with a 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) monolayer at the air-water interface was explored using a combination of experimental techniques and molecular dynamics (MD) simulations. By means of Langmuir trough methods and Brewster angle microscopy, L-phenylalanine was shown to significantly alter the interfacial tension and the surface domain mor...

Denna avhandling är skyddad enligt upphovsrättslagen. Alla rättigheter förbehålles. Abstract The principal objective of this thesis was to advance the level of understanding in the field of biolubrication, finding inspiration from the human synovial joints. This was addressed specifically by investigating the synergistic association of key biolubricants and the resulting lubrication performance...

The role of phospholipase A2 (PLA2) enzymes in the degradation of internalized dipalmitoylphospharidylcoline (DPPC) by rat granular pneumocytes was evaluated with cells in 24 h primary culture on microporous membranes. In cell sonicates and rat lung homogenates, the transition state analogue MJ33 inhibited acidic (pH 4), Ca(2+)-independent PLA2 (aiPLA2) while p-bromophenacylbromide (pBPB) inhib...