Precise parallel volumetric comparison of molecular surfaces and electrostatic isopotentials.

Geometric comparisons of binding sites and their electrostatic properties can identify subtle variations that select different binding partners and subtle similarities that accommodate similar partners. Because subtle features are central for explaining how proteins achieve specificity, algorithmic efficiency and geometric precision are central to algorithmic design. To address these concerns, this paper presents pClay, the first algorithm to perform parallel and arbitrarily precise comparisons of molecular surfaces and electrostatic isopotentials as geometric solids.

Interaction of gentamicin with phosphatidylserine/phosphatidylcholine mixtures in adsorption monolayers and thin liquid films: morphology and thermodynamic properties.

Gentamicin possesses strong adverse actions like oto and nephrotoxicity. The latter is a result of strong gentamicin-acid phospholipid interactions, resulting in cell fusion, fission, etc., ions as calcium interact with gentamicin and effectively deter its toxicity.

Influence of steroid hormone progesterone on the properties of phosphatidyl serine monolayers and thin liquid films.

In this work the capability of Progesterone (Prog) to penetrate to phosphatidyl serine (PS) monolayers (detected by equilibrium and dynamic surface tensions) and to induce rupture of PS thin liquid films (TLFs, known as foam films) in presence of Ca(2+) ions is studied. TLF studies reveal that the presence of Ca(2+) ions changes the type of PS films from thicker common black films to bilayer Newton black films and that the addition of Prog results in film destabilization and rupture. The effects of Prog in presence of Ca(2+) ions were observed with the films consisting of negatively charged PS but not of neutral phospholipids.

Effects of poly (ethylene glycol) chains conformational transition on the properties of mixed DMPC/DMPE-PEG thin liquid films and monolayers.

Foam thin liquid films (TLF) and monolayers at the air-water interface formed by DMPC mixed with DMPE-bonded poly (ethylene glycol)s (DMPE-PEG(550), DMPE-PEG(2000) and DMPE-PEG(5000)) were obtained. The influence of both (i) PEG chain size (evaluated in terms of Mw) and mushroom-to-brush conformational transition and (ii) of the liposome/micelle ratio in the film-forming dispersions, on the interfacial properties of mixed DMPC/DMPE-PEG films was compared. Foam film studies demonstrated that DMPE-PEG addition to foam TLFs caused (i) delayed kinetics of film thinning and black spot expansion and (ii) film stabilization.

Thin liquid films and monolayers of DMPC mixed with PEG and phospholipid linked PEG.

In this work thin liquid films (TLFs) and monolayers at the air/water interface formed by dimyristoylphosphatidylcholine (DMPC) and by DMPC mixed with poly ethylene glycols (PEGs) and dimyristoylphosphatidylethanolamine (DMPE) linked PEGs were studied. Film forming dispersions were composed of two types of particles: liposomes and micelles. TLFs stability, threshold concentration C(t) (i.