OBJECTIVE Brucine was encapsulated into stealth liposomes using the ammonium sulfate gradient method to improve therapeutic index. MATERIALS AND METHODS Four brucine stealth liposomal formulations were prepared, which were made from different phosphatidylcholines (PCs) with different phase transition temperatures (T(m)). The PCs used were soy phosphatidylcholine (SPC), dipalmitoyl phosphatidy...

The thermotropic properties of binary mixtures of D-erythro-n-palmitoyl-dihydrosphingomyelin (16:0-DHSM), D-erythro-n-palmitoyl-sphingomyelin (16:0-SM), cholesterol, lathosterol, and 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) were studied by differential scanning calorimetry. Addition of sterol to 16:0-DHSM and 16:0-SM bilayers resulted in a progressive decrease in both the T(m) and the...

The effect of high hydrostatic pressure on the lipid bilayer hydration, the mean order parameter, and rotational dynamics of 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) and 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC) cholesterol vesicles has been studied by time-resolved fluorescence spectroscopy up to 1500 bar. Whereas the degree of hydration in the lipid headgroup and inter...

The aqueous extracts of the seeds oat ( Avena sativa L.), horse chestnut Aesculus hippocastanum L . ), soybean Glycine max cowherb Vaccaria hispanica [P. Mill.] Rauschert) and quinoa Chenopodium Willd.), roots soapwort Saponaria officinalis L.) without any preservatives were characterized in terms their surface tension, compression (dilational) rheology, foamability foam stability. saponin cont...

The structure and function of membrane proteins is partly determined by the interaction of these proteins with the lipids of the membrane. Peptides forming single membrane-spanning alpha-helices, such as the WALP peptide (acetyl-GWWL(AL)(n)WWA-amide), are good models for such interactions. This interaction can be studied by investigating the aggregation of peptides. If the peptides remain isola...

Using a novel laser-induced ultrasonic probe, we have examined the bulk viscoelastic properties of fully hydrated dipalmitoylphosphatidylcholine (DPPC) aligned multibilayers in terms of the anisotropic in-plane elastic stiffness (C11) and viscosity (eta 11). Our measurements of C11 are in accord with those reported on Brillouin light scattering on a similar system. Our measurements on viscosity...

The thermotropic behavior of the natural glycosphingolipids galactosylceramide, asialo-Gal beta 1-3GalNAc beta 1-4Gal(3-2 alpha NeuAc)beta 1-4Glc beta 1-Cer (GM1), sulfatide, GM1, NeuAc alpha 2-3Gal beta 1-3GalNAc beta 1-4Gal(3-2 alpha NeuAc)beta 1-4Glc beta 1-1Cer (GD1a), and NeuAc alpha 2-3Gal beta 1-3GalNAc beta 1-4Gal(3-2 alpha NeuAc8-2 alpha NeuAc)beta 1-4Glc beta 1-1 Cer (GT1b), and their...

PURPOSE Gastrointestinal (GI) side effects of the nonsteroidal anti-inflammatory drug (NSAID) diclofenac may be reduced if it is administered as a complex with phospholipid. The upper and lower GI permeability induced by a diclofenac-dipalmitoyl phosphatidyl choline (DPPC) complex were compared with those of diclofenac acid and its sodium salt in rats. METHODS Pharmacokinetic studies were car...

The interactions between a drug and lipids may be critical for the pharmacological activity. We previously showed that the ability of a fluoroquinolone antibiotic, ciprofloxacin, to induce disorder and modify the orientation of the acyl chains is related to its propensity to be expelled from a monolayer upon compression [1]. Here, we compared the binding of ciprofloxacin on DPPC and DPPG liposo...

OBJECTIVES To determine whether dexamethasone 'matures' the phosphatidylcholine (PC) composition of broncheoalveolar fluid in infants at high risk of neonatal chronic lung disease (CLD), either by increasing the proportion of dipalmitoylphosphatidylcholine (DPPC), expressed as a percentage of total PC (%DPPC), or by increasing the ratio of DPPC to palmitoyloleoylphosphatidylcholine (DPPC:POPC r...