Search results for "LIPOSOMES"
showing 10 items of 221 documents
Janus -faced liposomes enhance antimicrobial innate immune response in Mycobacterium tuberculosis infection
2012
We have generated unique asymmetric liposomes with phosphatidylserine (PS) distributed at the outer membrane surface to resemble apoptotic bodies and phosphatidic acid (PA) at the inner layer as a strategy to enhance innate antimycobacterial activity in phagocytes while limiting the inflammatory response. Results show that these apoptotic body-like liposomes carrying PA (ABL/PA) ( i ) are more efficiently internalized by human macrophages than by nonprofessional phagocytes, ( ii ) induce cytosolic Ca 2+ influx, ( iii ) promote Ca 2+ -dependent maturation of phagolysosomes containing Mycobacterium tuberculosis (MTB), ( iv ) induce Ca 2+ -dependent reactive oxygen species (ROS) production, (…
Effect of the surface charge of liposomes on their uptake by angiogenic tumor vessels
2003
Recently, cationic liposomes have been shown to preferentially target the angiogenic endothelium of tumors. It was the aim of our study to investigate the influence of liposomal surface charge on the uptake and kinetics of liposomes into solid tumors and tumor vasculature. Experiments were performed in the amelanotic hamster melanoma A-Mel-3 growing in the dorsal skinfold chamber preparation of male Syrian golden hamsters. Fluorescently labeled liposomes with different surface charge were prepared. Accumulation of i.v. injected liposomes was assessed by quantitative intravital fluorescence microscopy of tumor and surrounding host tissue. The histological distribution of liposomes was analyz…
Gene therapy with iNOS enhances regional contractility and reduces delayed contrast enhancement in a model of postischemic congestive heart failure
2012
Aims: The purpose of this study was to evaluate the effect of transient local myocardial gene transfer of iNOS on cardiac function in a large mammal animal model of heart failure induced by chronic ischemia. Methods: Chronic myocardial ischemia was induced using a minimally invasive model in 16 landrace pigs. Upon demonstration of heart failure, eight animals were treated with liposome-mediated iNOS-gene-transfer by local intramyocardial injection; eight animals received a sham procedure to serve as control. Results: The transmurality of late enhancement (control: 46.4%, iNOS: 35.9%; p < 0.05) was significantly decreased in the ischemic area in the iNOS-treated group. Wall thickness at end-…
Freeze-dried eudragit-hyaluronan multicompartment liposomes to improve the intestinal bioavailability of curcumin.
2016
This work aimed at finding an innovative vesicle-type formulation able to improve the bioavailability of curcumin upon oral administration. To this purpose, phospholipid, Eudragit® S100 and hyaluronan sodium salt were combined to obtain eudragit-hyaluronan immobilized vesicles using an easy and environmentally-friendly method. For the first time, the two polymers were combined in a system intended for oral delivery, to enhance curcumin stability when facing the harsh environment of the gastrointestinal tract. Four different formulations were prepared, keeping constant the amount of the phospholipid and varying the eudragit-hyaluronan ratio. The freeze-drying of the samples, performed to inc…
Fate of Linear and Branched Polyether-Lipids In Vivo in Comparison to Their Liposomal Formulations by 18F-Radiolabeling and Positron Emission Tomogra…
2015
In this study, linear poly(ethylene glycol) (PEG) and novel linear-hyperbranched, amphiphilic polyglycerol (hbPG) polymers with cholesterol (Ch) as a lipid anchor moiety were radiolabeled with fluorine-18 via copper-catalyzed click chemistry. In vivo investigations via positron emission tomography (PET) and ex vivo biodistribution in mice were conducted. A systematic comparison to the liposomal formulations with and without the polymers with respect to their initial pharmacokinetic properties during the first hour was carried out, revealing remarkable differences. Additionally, cholesterol was directly labeled with fluorine-18 and examined likewise. Both polymers, Ch-PEG27-CH2-triazole-TEG-…
A 6 day course of liposomal amphotericin B in the treatment of infantile visceral leishmaniasis: the Italian experience
2004
Objectives To evaluate in a retrospective analysis the efficacy and safety of a 6 day course of liposomal amphotericin B (L-AmB) in infantile cases of Mediterranean visceral leishmaniasis (VL) diagnosed over a 10 year period in Italy. Patients and methods Patients included were diagnosed as having VL consecutively admitted from December 1992 to December 2001 at four main referral children's hospitals in Italy and treated with six intravenous doses of 3 mg/kg L-AmB given on days 1-5 and 10 (a total dose of 18 mg/kg). Demographic data, nutritional status, underlying diseases, clinical and laboratory findings, and therapy outcome were considered. Results A total of 164 HIV-negative children (m…
Antimetastatic Effect of Immunization with Liposome-Encapsulated Tumor Cell-Membrane Proteins Obtained from Experimental Tumors
1995
Immunization of C57BL/6 mice with tumor-derived membrane-proteins encapsulated in sized liposomes (0.2 microgram/mouse) and composed by phosphatidylcholine or sphingomyelin, significantly reduced the mean values of spontaneous lung metastasis from both B16 (0.7 +/- 0.5 and 1.2 +/- 0.6, respectively) and 3LL (4.8 +/- 2.5 and 7.2 +/- 4.1, respectively) tumors, with respect to control (HEPES) groups (4.8 +/- 1.1 and 19.0 +/- 4.4, respectively). However, no significant antimetastatic effect was observed using free tumor-derived proteins (2 micrograms/mouse) or liposome vehicle alone. Specific humoral immune response after the vaccination was studied by flow cytometry of tumor cells incubated wi…
EARLY EFFICACY OF LIPOSOMAL AMPHOTERICIN B IN THE TREATMENT OF VISCERAL LEISHMANIASIS
1996
The rapidity and efficacy of a short course of liposomal amphotericin B was evaluated in 29 children affected by visceral leishmaniasis (Leishmania infantum). Their overall health status was assessed using the prognostic inflammatory and nutritional index (PINI), and their haematological status by the reticulocyte count and haemoglobin blood levels. All these quantities were measured on day 0, and 3 and 10 d after starting therapy. A significant decrease of inflammatory signs, associated with an improved reticulocyte count, was recorded after 3 d of therapy. A significant increase of haemoglobin levels was also observed 10 d after the start of treatment. The early reduction of inflammatory …
Immuno-toxicological Evaluation of the Adjuvant Formulations for Experimental Anti-meningococcal Vaccines without Aluminium Hydroxide
2019
International audience; The proteoliposomes and cochleates are used as adjuvants for vaccines since they are potent immune stimulators. However, the hyper stimulation of the immune system provoked by adjuvants can cause immunetoxicological side effects. The present study was carried out to evaluate the toxic and immuno-toxicological effects of new adjuvants for anti-meningococci vaccines based on neo-proteoliposomes (nPL) and neocochleates (nCh), in Balb/c mice that were administered doses of 15 µg each, over periods of 14 days through intramuscular route and three inoculations with the same doses through intranasal route, every 7 days. The Scanning and Transmission Electron Microscopy show…
Influence of different parameters on drug release from hydrogel systems to a biomembrane model. Evaluation by differential scanning calorimetry techn…
2000
A comparative study on the drug release capacity of four water swellable polymeric systems was carried out by differential scanning calorimetry (DSC). The polymeric systems chosen were alpha,beta-polyaspartahydrazide (PAHy) crosslinked by glutaraldehyde (GLU) (PAHy-GLU) or by ethyleneglycoldiglycidylether (EGDGE), (PAHy-EGDGE), polyvinylalcohol (PVA) crosslinked by glutaraldehyde (PVA-GLU) and alpha,beta-poly(N-hydroxyethyl)-DL-aspartamide (PHEA) by gamma irradiation (PHEA-gamma matrices). The degree of crosslinking for PAHy-GLU, PAHy-EGDGE and PVA-GLU samples was about 0.4 and 0.8. These hydrogels were characterized as free of drugs and were loaded with diflunisal (DFN) (approximately 2.5%…