A hybrid silica-liposome nanocapsule system containing insulin has been developed and the encapsulation, protection and release properties are evaluated. The formulation strategy is based on using insulin-loaded 1,2-dipalmitoyl-sn-glycero-3-phosphocholine and cholesterol liposomes as a template for the deposition of inert silica nanoparticles. The ...

Long-circulating liposomes, such as PEG-liposomes, are frequently studied for drug delivery and diagnostic purposes. In our group, poly(amino acid) (PAA)-based coatings for long-circulating liposomes have been developed. These coatings provide liposomes with similar circulation times as compared to ...

Secretory phospholipase A(2) (sPLA(2)) expression is increased in several cancers and has been shown to trigger release from some lipid carriers. This study used electrospray ionization mass spectrometry (ESI-MS) and release of 6-carboxyfluorescein (6-CF) to determine the effects of sPLA(2) on various liposome formulations. Different ...

Neurotensin-degrading enzyme (NTDE) inhibitors hold great potential for treating psychotic disorders. However, brain uptake of such compounds in vivo is generally low due to the presence of the blood-brain barrier. In this study, liposomal formulations of two NTDE inhibitors, named compound 1 (C1) and compound 2 (C2) were prepared. Association of these ...

1. Unique among the phospholipids, phosphatidylserine depresses brain energy metabolism when injected intravenously into mice in the form of sonicated liposomes. The possibility that this effect results from a metabolic transformation of phosphatidylserine is examined in this paper. 2. A strong enhancement of the phosphatidylserine effect is induced by the incubation of ...

Structural requirements of inorganic phosphorus compounds as specific activators or inhibitors for phospholipase A2 and phospholipase B were investigated using orthophosphate, pyrophosphate and polyphosphate. It was observed that orthophosphate and pyrophosphate stimulated the activities of phospholipase A2 from ...

This progress report describes our research in studying the in vivo properties of liposomes as a potential drug carrier for trypanocidal agents. The first section discusses the effect of chemical composition, size, and concentration on the degradation of ...

1. The plasma decay, tissue uptake and biotransformation of radiolabelled phosphatidylserine (PS) liposomes have been investigated in rats following bolus i.v. injection (2 mg kg-1). 2. PS plasma concentration showed a biexponential decay with half-lives of 0.85 and 40 min. The following interpretation of the biphasic decay is proposed: (1) The rapid initial decline is due to ...

1. The plasma decay, tissue uptake and biotransformation of radiolabelled phosphatidylserine (PS) liposomes have been investigated in rats following bolus i.v. injection (2 mg kg-1). 2. PS plasma concentration showed a biexponential decay with half-lives of 0.85 and 40 min. The following interpretation of the biphasic decay is proposed: (1) The rapid initial decline is due to ...

Aging of cattail (Typha latifolia L.) pollen was studied at 24[deg]C under conditions of 40 and 75% relative humidity (RH). The decline of viability coincides with increased leakage at imbibition; both processes develop much faster at the higher humidity condition. During aging phospholipids are deesterified and free fatty acids (FFAs) and lysophospholipids (LPLs) accumulate, again, much more ...

The objective of the present study was to synthesize monomethoxypolyethyleneglycol-5000 cholesteryl ester [PEG-CH] as a cost-effective substitute for polyethyleneglycol-phosphatidylethanolamine and to evaluate the influence of its incorporation in liposomal bilayers for surface modification. PEG-CH was synthesized and characterized by infrared (IR), proton nuclear magnetic ...

The annexin (p35) was isolated from the fruits of green pepper (Capsicum annum). The partial amino acid sequence of p35 was analyzed. p35 had an endonexin fold as annexin consensus sequences. Purified p35 had other annexin like characters such as strongly bind to phosphatidylserine and phosphatidylinositol, phospholipase A2 inhibition and ...

Liposomes have been used as imaging and therapeutic agents in various tissues but only infrequently in the cardiovascular system. We prepared a liposome to target atheromas in a Watanabe heritable hyperlipidemic (WHHL) rabbit model. Liposomes labeled with rhodamine and nanogold were injected intra-arterially into the descending ...

We have recently introduced liposome-supported plasmon resonant gold nanoshells (Troutman et al., Adv. Mater. 2008, 20, 2604�2608). These plasmon resonant gold-coated liposomes are degradable into components of a size compatible with renal clearance, potentially enabling their use as multifunctional agents in applications in ...

We have recently introduced liposome-supported plasmon resonant gold nanoshells (Troutman et al., Adv. Mater. 2008, 20, 2604-2608). These plasmon resonant gold-coated liposomes are degradable into components of a size compatible with renal clearance, potentially enabling their use as multifunctional agents in applications in ...

The objective of this work has been the microencapsulation of Asiatic Pennywort (AP) extract with lecithin from soybean. The effect of various quantities of non-ionic surfactant (Montanov82) on liposomes upon physicochemical characteristics as well as their in vitro bio-activities was investigated. An addition of surfactant resulted in a decrease in particle size and an ...

Closo-dodecaborate lipid liposomes were developed as new vehicles for boron delivery system (BDS) of neutron capture therapy. The current approach is unique because the liposome shell itself possesses cytocidal potential in combination with neutron irradiation. The liposomes composed of closo-dodecaborate lipids DSBL and DPBL displayed ...

Liposomes can be used to exploit the altered biology of cancer thereby increasing delivery of liposome-associated anti-cancer drugs. In this dissertation, I explore methods that utilize the unique cancer expression of the polymeric glycosaminoglycan hyaluronan (HA) and the HA receptor CD44 to target liposomes to tumors, using ...

The kinetics of hepatic uptake and degradation of sphingomyelin/cholesterol (2:1, M/M) small unilamellar liposomes were investigated in a BALB/c mouse. The tissue distribution of liposomes was determined by scintillation spectrometry. The percentage of intact liposomes in tissues was estimated by the technique of ...

... Liposomes, Carriers, Vaccines, Malaria ... LIPOSOMES AS CARRIERS OF VACCINES: DEVEIOPMENT OF A LIPOSOMAL MALARIA VACCINE ...

We have purified two phospholipase A2 inhibitory proteins (37 and 33 kDa) from peritoneal fluid of dexamethasone-treated rats. The extracellular phospholipase A2 found in inflammatory sites differed from the exocrine phospholipase A2 in susceptibility to these endogenous ...

We have purified two phospholipase A2 inhibitory proteins (37 and 33 kDa) from peritoneal fluid of dexamethasone-treated rats. The extracellular phospholipase A2 found in inflammatory sites differed from the exocrine phospholipase A2 in susceptibility to these endogenous ...

liposomes and their degradation in cells increased intracellular-free DNA.16 We observed that intravenously. This result suggested that degradation of PAGA might increase intracellular- free DNA. Further investigation-7128/00 $15.00 www.nature.com/gt ACQUIRED DISEASES RESEARCH ARTICLE Degradable polymeric carrier

Unilamellar vesicles or �liposomes� are commonly used as simple cell models and as drug delivery vehicles. A major limitation of unilamellar liposomes in these applications has been premature contents release in physiological environments. This premature release is likely due to enzyme degradation or protein insertion into the ...

Proliposomes of ibuprofen were successfully prepared using effervescent granules as solid carriers of dried phospholipids along with other lipids (soyabean lecithin, stearylamine and cholesterol). Liposomes of regular size with uniform size distribution resulted when proliposomal formulations were hydrated under the effervescence produced by the production of carbon dioxide ...

Background:Oral delivery of insulin is challenging and must overcome the barriers of gastric and enzymatic degradation as well as low permeation across the intestinal epithelium. The present study aimed to develop a liposomal delivery system containing glycocholate as an enzyme inhibitor and permeation enhancer for oral insulin ...

We recently demonstrated that liposome-supported plasmon resonant gold nanoshells are degradable into components of a size compatible with renal clearance, potentially enabling their use as multifunctional agents in applications in nanomedicine, including imaging, diagnostics, therapy, and drug delivery (Troutman et al., Adv. Mater. 2008, 20, 2604�2608). ...

We recently demonstrated that liposome-supported plasmon resonant gold nanoshells are degradable into components of a size compatible with renal clearance, potentially enabling their use as multifunctional agents in applications in nanomedicine, including imaging, diagnostics, therapy, and drug delivery (Troutman et al., Adv. Mater. 2008, 20, 2604-2608). ...

Electron paramagnetic resonance imaging (EPRI) allows detection and localization of paramagnetic spin probes in vivo and in real time. We have shown that nitroxide spin probes entrapped in the intracellular milieu can be imaged by EPRI. Therefore, with the development of a tumor-targetable vehicle that can efficiently deliver nitroxides into cells, it should be possible to use nitroxide spin ...

A computer-based technique was applied for the optimization of recently described multicomponent protective liposomal formulations. These formulations contain riboflavin in either free form or complexed with gamma-cyclodextrin as a model drug, sensitive to photochemical degradation, as well as various light absorbers and antioxidants incorporated into the ...

Paclitaxel, an antitumoral drug, is poorly soluble in aqueous media. Therefore, in a commercialised formulation (Taxol), paclitaxel (30 mg active compound) is dissolved in polyethoxylated castor oil (Cremophor EL) and ethanol. After dilution of Taxol in aqueous media paclitaxel tends to precipitate. Several side effects, attributed to the surfactant Cremophor EL, occur, e.g. bronchospasm, ...

A nerve growth factor (NGF) was encapsulated into liposomes in order to protect it from the enzyme degradation in vivo and promote it permeability across the blood-brain barrier (BBB). RMP-7, a ligand to the B2 receptor on brain microvascular endothelial cells (BMVEC), was combined with ...

We have shown that platelets are capable of phagocytosing liposomes rather than simply sequestering particles as previously postulated. Incubation of human platelets with small neutral unilamellar liposomes (approximately 74 nm) resulted in uptake of the liposomes and retention of the lipid with rapid release of the aqueous-phase ...

Amphotericin B (AmB) liposome formulations are very successful in the treatment of fungal infections and leishmaniasis. But higher cost limits its widespread use among people in developing countries. Therefore, we have developed a modified ethanol-injection method for the preparation of AmB liposomes. Two liposomal formulations were ...

We hypothesized that constitutive formation of reactive oxygen species by respiratory cells is a barrier to gene transfer when liposome-DNA complexes are used, by contributing to rapid degradation of plasmid DNA. When plasmid DNA is complexed to liposomes it is protected against H(2)O(2)-mediated degradation but ...

To evaluate liposome formulations for use as intracellular sustained-release drug depots, we have compared the uptake and degradation in rat liver and spleen of liposomes of various compositions, containing as their bulk phospholipid an ether-linked phospholipid or one of several ester-linked phospholipids, by perturbed angular ...

To evaluate liposome formulations for use as intracellular sustained-release drug depots, we have compared the uptake and degradation in rat liver and spleen of liposomes of various compositions, containing as their bulk phospholipid an ether-linked phospholipid or one of several ester-linked phospholipids, by perturbed angular ...

There is controversy as to whether the cell entry mechanism of Sindbis virus (SIN) involves direct fusion of the viral envelope with the plasma membrane at neutral pH or uptake by receptor-mediated endocytosis and subsequent low-pH-induced fusion from within acidic endosomes. Here, we studied the membrane fusion activity of SIN in a liposomal model system. Fusion was followed ...

Liposomes are widely investigated for their use as drug delivery systems, where they have to meet strict stability criteria. Hence, it is of common interest to establish appropriate storage conditions to improve the shelf life of liposomes. In general, long-term stability can be achieved by freezing as well as freeze-drying, and different carbohydrates or ...

The present study demonstrates that the nutritional supplement S-adenosyl methionine (SAMe), the primary methyl donor in mammalian cells, is delivered selectively to cells by anionic liposomes, and is, therefore, a liposome dependent drug. Contrary to our expectations, free SAMe chloride was growth inhibitory in cultured cells. The growth inhibitory ...

Natural bioactive compounds have been studied for a long time for their chemopreventive and therapeutic potential in several chronic inflammatory diseases, including cancer. However, their physicochemical properties generally result in poor chemical stability and lack of in vivo bioavailability. Very few human clinical trials have addressed absorption, distribution, metabolism, and excretion of ...

... Accession Number : ADA224014. Title : Liposomes as Carriers of Vaccines: Development of a Liposomal Malaria Vaccine. ...

... Title : Immunologic Aspects of Liposomes: Presentation and Processing of Liposomal Protein and Phospholipid Antigens,. ...

Sphingomyelin and seven glycosphingolipids were labeled with the fluorescent probe pyrene and administered into cultured fibroblasts by receptor-mediated endocytosis. For this purpose pyrene sphingomyelin or mixtures of pyrene glycolipid and unlabeled sphingomyelin were dispersed as small, unilamellar liposomes. Apolipoprotein E was then added and the receptor for this ligand ...

Zanthoxylum tinguassuiba essential oil (ZtEO) contains ?-bisabolol, a known antiglioma sesquiterpene, among other potentially active substances. Medical applications of this essential oil require advances in the design of distinctive carriers due to its low water solubility and easy degradation by heat, light, and oxygen. The aim of this work was to evaluate enhancement in ...

Two new ?-phenyl polyketide peroxides, plakinic acids K and L, were isolated from a two-sponge association of Plakortis halichondroides and Xestospongia deweerdtae. The absolute configurations of the remote dimethyl-branched stereocenters in plakinic acid K were assigned by degradation of plakinic acid K to a long-chain naphthamide and analysis by ...

Uptake, degradation and reutilization of surfactant phospholipids was investigated by incubating granular pneumocytes in primary culture with 0.2 mM liposomal phosphatidylcholine containing (/sup 3/H-methyl)choline labeled dipalmitoyl PC. Trypsin-resistant cell associated liposome radioactivity in PC declined steadily with time of ...

To investigate the influence of the interfacial area and the emulsifier lecithin on the degradation rate of drugs prone to hydrolysis in parenteral lipid O/W emulsions we measured the degradation kinetics of phenyl salicylate in systems consisting of Miglyol as oil, buffered and isotonized aqueous phase and lecithin as emulsifier. Two-layer oil over water ...

Mutations in ATP13A2 (PARK9) have been linked to juvenile parkinsonism with dementia or Kufor-Rakeb syndrome (KRS). The ATP13A2 gene encodes at least three protein isoforms that arise by alternate splicing. A previous study indicated the Atp13a2(Isoform-1) protein is localized to lysosomes, whereas three separate mutations involved in disease cause retention of the protein in the ER. One ...

This article summarizes the development of an analytical method for the determination of proanthocyanidin (PAC) A2 in phenolic polymer isolates following acid-catalyzed degradation in the presence of excess phloroglucinol. Isolates from cranberry juice concentrate (CJC) were extensively characterize...

Annexin A2 is a calcium-dependent, phospholipid-binding protein found on various cell types. It is up-regulated in various tumor types and plays multiple roles in regulating cellular functions, including angiogenesis, proliferation, apoptosis, cell migration, invasion and adhesion. Annexin A2 binds with plasminogen ...

These studies are focused on antagonizing organophosphorous (OP) intoxications by a new conceptual approach using recombinant enzymes encapsulated within sterically stabilized liposomes to enhance diisopropylfluorophosphate (DFP) degradation. The OP hydrolyzing enzyme, organophosphorous acid anhydrolase (OPAA), encapsulated within the ...

This work reports the development of an automatic methodology based on the use of 1-anilinonaphthalene-8-sulfonate (ANS) as an interfacial fluorescent probe for detecting the hydrophobic environment shift around the probe, caused by the hydrolytic action of PLA(2) on the liposomes. The implementation of this reaction in a sequential injection analysis (SIA) system along with ...

P₄-ATPases comprise a relatively new subfamily of P-type ATPases implicated in the energy-dependent translocation of aminophospholipids across cell membranes. In this study, we report on the localization and functional properties of Atp8a2, a member of the P₄-ATPase subfamily that has not been studied previously. Reverse transcription-PCR revealed high ...

The antioxidant and membrane effects of dimer (Dim) and trimer (Trim) procyanidins isolated from cocoa (Theobroma cacao) (B- and C-bonded) and peanut (Arachis hypogea L.) skin (A-bonded) were evaluated in phosphatidyl choline liposomes. When liposomes were oxidized with a steady source of oxidants, the above dimers and trimers inhibited to a similar extent ...

... Title : Lipid A and Liposomes Containing Lipid A as Adjuvants ... Descriptors : *LIPIDS, *LIPOSOMES, *VACCINES, STRATEGY, IN VITRO ANALYSIS ...

... Monoclonal antibodies to liposomes and liposomal cons tuents, particularly phosphatidylinositol phosphate,, h been induced by immunizing ... 42 AM ...

The effects of gamma irradiation (25 kGy) as a sterilisation method for phospholipids (distearoylphosphatidylcholine and distearoylphosphatidylglycerol) were investigated. 31P-NMR revealed minor chemical degradation of the phospholipids but lower dynamic viscosity and pseudoplasticity, lower turbidity, higher diffusion constant, smaller size, more negative zeta potential and ...