We report on the preparation and characterization of poly(D, L-lactide-co-glycolide) (PLGA) microparticles with surface-conjugated polyamidoamine (PAMAM) dendrimers of varying generations. The buffering capacity and zeta-potential of the PLGA PAMAM microparticles increased with increasing generation level of the PAMAM dendrimer conjugated. Conjugation of the PAMAM dendrimer to the surface of th...

The effect of natural killer (NK) cells and lymphokine activated killer ( LAK) cells was studied on a group of human melanoma cell lines. Peripheral blood from healthy volunteers was utilized as a fresh source of natural killer cells and rhI L-2 for producing LAK cells. The cytotoxicity of effector cells was quantified using a 4 hour SI determining the density of antigen expression on tumor...

Magnetic mesoporous amorphous calcium phosphate nanoparticles with a size of 62 nm and abundant -COOH groups on the surface have been prepared by a simple method. The particles show excellent aqueous dispersion stability in physiological pH without any deterioration in hydrodynamic size and zetapotential. By virtue of the carboxylate groups on the surface, the platinum pharmacophore cis-diaquad...

objective(s): pei based nanoparticle (np) due to dual capabilities of proton sponge and dna binding is known as powerful tool for nucleic acid delivery to cells. however, serious cytotoxicity and complicated conditions, which govern nps properties and its interactions with cells practically, hindered achievement to high transfection efficiency. here, we have tried to optimize the properties of ...

Direct cytotoxicity of black-pigmented anaerobic rods was studied on the confluent monolayer of human gingival fibroblasts in vitro. Only strains of Porphyromonas gingivalis caused morphological alteration (cell-rounding) and notable depression of viability of fibroblasts. To determine the location of the cytotoxicity, bacterial surface components, i.e., outer membrane, lipopolysaccharide, fimb...

Titania-supported palladium, gold and bimetallic nanoparticles (second-generation nanoparticles) demonstrate promising photocatalytic properties. However, due to unusual reactivity, second-generation nanoparticles can be hazardous for living organisms. Considering the ever-growing number of new types of nanoparticles that can potentially contaminate the environment, a determination of their tox...

objective(s): although viral vectors are considered efficient gene transfer agents, their board application has been limited by toxicity, immunogenicity, mutagenicity and small gene carrying capacity. non-viral vectors are safe but they suffer from low transfection efficiency. in the present study, polyallylamine (paa) in two molecular weights (15 and 65 kda) was modified by alkane derivatives ...

objective(s): lipid-based nanoparticles (nlp) are pegylated carriers composed of lipids and encapsulated nucleic acids with a diameter less than 100 nm. the presence of peg in the nlp formulation improves the particle pharmacokinetic behavior. the purpose of this study was to prepare and characterize nlps containing mdr1 sirna and evaluate their cytotoxicity and cellular uptake. mdr1 sirna coul...

The cytotoxicity and time-dependent membrane disruption by polypropylenimine dendrimer conjugates on cultured human umbilical vein endothelial cells (HUVEC) is reported. Fluorescently labeled derivatives of generation 5 polypropylenimine dendrimers were prepared via conversion of amines to acetamides or through the covalent attachment of high molecular weight poly(ethylene glycol) (PEG) chains....

Concanavalin A stimulation of T-cell cytotoxicity has been shown to be absolutely dependent on helper T-cell collaboration. Thymocytes stimulated with ConA do not differentiate to yield cytotoxic effector cells. However, thymocytes cocultured with irradiated spleen cells as helpers and ConA yield high levels of cytotoxicity. The helper cell bears theta antigens on its surface, is not an adheren...