Astaxanthin and peridinin, two typical carotenoids of marine microalgae, and lycopene were incorporated in phosphatidylcholine multilamellar liposomes and tested as inhibitors of lipid oxidation. Contrarily to peridinin results, astaxanthin strongly reduced lipid damage when the lipoperoxidation promoters-H(2)O(2), tert-butyl hydroperoxide (t-ButOOH) or ascorbate-and Fe(2+):EDTA were added simu...

To advance our understanding of the organization of cholesterol within cell membranes, we used digitonin in freeze-fracture investigations of model lipid vesicles and tissues. Cholesterol suspensions or multilamellar liposomes composed of phosphatidylcholine with and without cholesterol were exposed to digitonin. Freeze-fracture replicas of those multilamellar liposomes containing cholesterol d...

A microfluidic process has been newly proposed to synthesize highly unique micrometer-size hybrid liposomes having multi-lamellae structure. The process includes (1) formation of monodisperse droplets of a polar solvent containing phospholipids at a microchannel confluence, (2) dissolution of the solvent into the continuous water phase, and (3) simultaneous reconstitution of large multilayer me...

Monocyte-mediated cytotoxicity (determined in a 72-h111In release assay) and the circulating levels of tumor necrosis factor alpha (TNF-alpha), interleukin (IL) 1beta, IL-6, IFN-gamma, C-reactive protein, and beta2-microglobulin were determined in 14 melanoma patients treated with multilamellar vesicle liposomes containing muramyl tripeptide phosphatidylethanolamine, 4 mg twice a week for 12 we...

Formulation of local anesthetics in liposomal topical drug delivery system could provide a sustained and localized anesthesia. The aim of this study was to develop a liposomal dibucaine base (DB) local anesthetic delivery system. DB-loaded multilamellar vesicles (MLVs) were prepared through varying lipid composition, induced charge and pH of the hydration medium. Liposomes were characterized fo...

To advance our understanding of the organization of cholesterol within cell membranes, we used digitonin in freeze-fracture investigations of model lipid vesicles and tissues. Cholesterol suspensions or multilamellar liposomes composed of phosphatidylcholine with and without cholesterol were exposed to digitonin. Freeze-fracture replicas of those multilamellar liposomes containing cholesterol d...

A role of carotenoids as modulators of physical properties of model and biological membranes has been already postulated. However, there is a lack of information on the influence of these pigments on interactions between the lipids which form such membranes. This paper applies atomic force microscopy (AFM) in to study the effects of β-carotene on the adhesion properties of DPPC multilamellar li...

The purified major intrinsic protein of the lens fiber plasma membrane (MP26) reconstituted into liposomes favored membrane-to-membrane close contacts as visualized by freeze fracture and immunoelectron microscopy. Reconstituted apposed unilamellar vesicles formed pentalaminar profiles, and multilamellar liposomes showed regions of stacked bilayers. Immunogold labeling, using antibody directed ...

Functional and ultrastructural studies of liposomes injected i.v. into inbred C57BL/6N mice were performed to determine whether free liposomes can traverse capillaries. In the liver and spleen, organs with discontinuous (sinusoidal) capillaries, ultrastructural and cell fractionation studies revealed that small (300- to 800-A diameter), sonicated, unilamellar liposomes were more efficient in pe...

Most subunit vaccines require adjuvants in order to induce protective immune responses to the targeted pathogen. However, many of the potent immunogenic adjuvants display unacceptable local or systemic reactogenicity. Liposomes are spherical vesicles consisting of single (unilamellar) or multiple (multilamellar) phospholipid bi-layers. The lipid membranes are interleaved with an aqueous buffer,...