46 research outputs found
The role of protamine amount in the transfection performance of cationic SLN designed as a gene nanocarrier
Cationic solid lipid nanoparticles (SLN) have been recently proposed as non-viral vectors in systemic gene therapy. The aim of this study was to evaluate the effect of the protamine amount used as the transfection promoter in SLN-mediated gene delivery. Three protamine-SLN samples (Pro25, Pro100, and Pro200) prepared by adding increasing amounts of protamine were characterized for their size, zeta potential, and protamine loading level. The samples were evaluated for pDNA complexation ability by gel-electrophoresis analysis and for cytotoxicity and transfection efficiency by using different cell lines (COS-I, HepG2, and Na1300). The size of SLN was ~230 nm and only Pro200 showed few particle aggregates. Unlike the Pro25 sample with the lowest protamine loading level, the others SLN samples (Pro100 and Pro200) exhibited a good ability in complexing pDNA. A cell-line dependent cytotoxicity lower than that of the positive control PEI (polyethilenimmine) was observed for all the SLN. Among these, only Pro100, having an intermediate amount of protamine, appeared able to promote pDNA cell transfer, especially in a neuronal cell line (Na1300). In conclusion, the amount of protamine as the transfection promoter in SLN affects not only the gene delivery ability of SLN but also their capacity to transfer genes efficiently to specific cell types
Complete aromatase deficiency in four adult men: detection of a novel mutation and two known mutations in the CYP19A1 gene
The abstracts descibes four new cases of patients with aromatase deficiency. Both the clinical features and the results of the molecular studies are reported
Studying the in vitro behaviour of cationic solid lipid nanoparticles as a nonviral vector
SLNs are basically composed of a solid lipid core in nanometer ranges stabilized by a layer of emulsifier; they can be prepared by using lipids with a relatively high melting point (i.e., triglycerides, hard fat types, partial glycerides, steroids and waxes). Among these lipids, glycerides, which are composed of fatty acids, can be employed in injection form since they are already used in parenteral nutritio
Influence of secondary preparative and aging effects on PLGA particle size distribution: a sedimentation field-flow fractionation investigation
Poly(lactic-co-glycolic acid) (PLGA) is a well-characterized polymer from the ester family, widely used in the biomedical industry since its degradation byproducts are non toxic. As biodegradable colloidal particle, PLGA is an excellent delivery carrier for drugs, genes, proteins and various other macromolecules because it shows high stability, has high carrier capacity, can feasibly incorporate both hydrophilic and hydrophobic substances, and offers various feasibly routes of administration. Several methods are currently employed to formulate PLGA particles with the smallest possible sizes and maximum stability for pharmaceutical applications
In this project PLGA particles, in the 200-400 nm size range, were prepared by nanoprecipitation and single emulsion (or solvent evaporation) methods in order to achieve particles which can be stable in the long run, that have appropriate dimensions for injectable uses and that disperse themselves well in aqueous media, a key requirement for uses as vehicles to induce in vivo drug targeting. Different concentrations of polymer and stabilizing (Pluronic® F68) were tested in order to identify the best conditions for making PLGA particles of suitable size, stable in time, to be used as carriers for brain targeting drugs.
The particles with the best characteristics for delivery system design were those formulated by nanoprecipitation with an organic/water phase ratio of 2/30, a polymer concentration of 25 mg/mL and a surfactant concentration of 0.83 mg/mL; their surface charge was reasonably negative (~ -27 mV) and the average size of the almost monodisperse population was roughly 250 nm.
Particle characterization was accomplished by using SEM to check the morphology, calculating the surface charge through -potential measurements and determining the average sizes and particle size distributions (PSDs), the latter achieved by both PCS (photon correlation spectroscopy) and SdFFF (sedimentation field flow fractionation). SdFFF, the technique considered more reliable than PCS in describing the possible PSD modifications was used to investigate the effects three months of storage at 4 °C had on the lyophilized particles
In vitro behaviour of multicomposite cationic SLN as new platform for pDNA delivery
The enhancement of non viral vectors is a priority in the field of gene therapy, in order to manage effective and safe vectorsi. Among non viral vectors, solid lipid nanoparticles (SLN) have emerged in the last years as an alternative to liposomes and PEI (poly-ethylene-imine) and many efforts have been spent in order to improve their performanceii. The present study aims to design and characterize in vitro multicomposite SLN as a novel platform for pDNA delivery: SLN matrix composition was modified by assembling several components able to optimize the carrier in terms of transfection efficieny and safety. In details, stearic acid was selected as the main lipid component along with stearylamine as its analogous cationic compound. Protamine and Pluronic F68 were included in the formulation as transfection promoter and surfactant, respectively. Cholesterol (Chol) and phosphatidylcholine (PC) were added to improve biocompatibility and plasticity of the carriers
Development of new formulations of cationic solid lipid nanoparticles (SLNs) for the drug delivery to the brain
Development of new formulations of cationic solid lipid nanoparticles (SLNs) for the drug delivery to the brai
Formulazione e caratterizzazione di nanoparticelle polimeriche per la somministrazione orale di eparina
Nanoparticelle polimeriche per la somministrazione di eparina. studi di caratterizzazione tecnologica ed uptake in CACO-
Preparation and physical stability evaluation of cationic solid lipid nanoparticles
Preparation and physical stability evaluation of cationic solid lipid nanoparticle
Central Hypogonadotropic Hypogonadism: Genetic Complexity of a Complex Disease
Central hypogonadotropic hypogonadism (CHH) is an emerging pathological condition frequently associated with overweight, metabolic syndrome, diabetes, and midline defects. The genetic mechanisms involve mutations in at least twenty-four genes regulating GnRH neuronal migration, secretion, and activity. So far, the mechanisms underlying CHH, both in prepubertal and in adulthood onset forms, remain unknown in most of the cases. Indeed, all detected gene variants may explain a small proportion of the affected patients (43%), indicating that other genes or epigenetic mechanisms are involved in the onset of CHH. The aim of this review is to summarize the current knowledge on genetic background of CHH, organizing the large amount of data present in the literature in a clear and concise manner, to produce a useful guide available for researchers and clinicians