Background: In Covid-19 the virus infects respiratory tract in human. When lung tissue becomes diseased, walls and lining of alveoli capillaries are damaged. At this point compliance ventilation decrease. Pulmonary surfactant that is produced dispersed into alveolar space, has a significant role understanding how heavily covid-19 interferes cells. The importance pulmonary to lower surface tensi...

Phase-sensitive vibrational sum frequency generation is employed to investigate the water structure at phospholipid/water interfaces. Interfacial water molecules are oriented preferentially by the electrostatic potential imposed by the phospholipids and have, on average, their dipole pointing toward the phospholipid tails for all phospholipids studied, dipalmitoyl phosphocholine (DPPC), dipalmi...

The structure of the Lc8 phase exhibited by hydrated dipalmitoylphosphatidylcholine ~DPPC! was recently determined by Raghunathan and Katsaras @Phys. Rev. Lett. 74, 4456 ~1995!# from x-ray diffraction studies on oriented multibilayers. Here, we reanalyze the powder diffraction data reported in the literature on a number of hydrated lipids possessing the phosphatidylcholine headgroup. As in DPPC...

Background: Although initially proposed by von Neergaard in 1929 (14), direct evidence for surface-active material at the air-fluid interface of the lung was first reported by Richard Pattle and John Clements in the 1950s (5, 10). Pattle deduced that microbubbles formed from lung washings could reduce surface tension ( ) to near 0 mN/m. Using his modified Langmuir-Wilhelmy balance, Clements dem...

Polyhydroxyalkanoates (PHA) are polyesters produced intracellularly by many bacterial species as energy storage materials, which used in biomedical applications, including drug delivery systems, due to their biocompatibility and biodegradability. In this study, we evaluated the potential application of nanomaterial a basis inhaled systems. To that end, assessed possible interaction between PHA ...

We implement the replica exchange molecular dynamics algorithm to study the interactions of a model peptide (WALP-16) with an explicitly represented DPPC membrane bilayer. We observe the spontaneous, unbiased insertion of WALP-16 into the DPPC bilayer and its folding into an alpha-helix with a transbilayer orientation. The free energy surface suggests that the insertion of the peptide into the ...

Measurements of normal and shear (frictional) forces between mica surfaces across small unilamellar vesicle (SUV) dispersions of the phosphatidylcholine (PC) lipids DMPC (14:0), DPPC (16:0) and DSPC (18:0) and POPC (16:0, 18:1), at physiologically high pressures, are reported. We have previously studied the normal and shear forces between two opposing surfaces bearing PC vesicles across pure wa...

BACKGROUND Repeated doses of recombinant apolipoprotein A-I(Milano) phospholipid complex (apoA-I(m)) reduce atherosclerosis and favorably change plaque composition in rabbits and mice. In this study, we tested whether a single high dose of recombinant apoA-I(m) could rapidly mobilize tissue cholesterol and reduce plaque lipid and macrophage content in apoE-deficient mice. METHODS AND RESULTS ...

Blood and its components flood the alveoli in adult respiratory distress syndrome (ARDS) and may be responsible for the inhibition of lung surfactant in this syndrome. We have evaluated the surface properties of dipalmitoyl phosphatidylcholine (DPPC) monolayers-the main component of lung surfactant, in the presence of blood and its components. Experiments were performed using a Langmuir-Blodget...