Micro-computed tomography imaging of composite nanoparticle distribution in the lung.

Nanomedicine comprises a significant potential to approach the therapy of severe diseases. Knowledge of nanoparticle behavior at the target site would contribute to the development of specialized tools for respiratory medicine. Here, we were interested in the potential of micro-computed tomography (μCT) imaging to monitor the pulmonary distribution of polymeric nanoparticles.

Synthesis of a new potential biodegradable disulfide containing poly(ethylene imine)-poly(ethylene glycol) copolymer cross-linked with click cluster for gene delivery.

Poly(ethylene glycol)-grafted-polyethylenimine (PEG-PEI) are promising non-viral gene delivery systems. Herein, we aimed to synthesize a biodegradable disulfide containing PEGylated PEI to attempt to reduce its cytotoxicity and enhance the gene transfer activity. Using click chemistry, low Mw PEI (br.

Amphiphilic, low molecular weight poly(ethylene imine) derivatives with enhanced stability for efficient pulmonary gene delivery.

Background: Poly(ethylene imine) (PEI) is a widely used transfection reagent for mammalian cells, but in vivo application of PEI 25 kDa is restricted by its toxicity. Low molecular weight (LMW) PEI is less toxic, but also less efficient than its high molecular weight equivalent, and prone to aggregation.

Method: A set of polymers was synthesized by coupling poly(ethylene glycol) (PEG) that contained either C(16/18) -chains (Cx-EO) or butyl-poly(propylene oxide)-co-poly(ethylene glycol) (ButPP).

Surfactant-free redispersible nanoparticles in fast-dissolving composite microcarriers for dry-powder inhalation.

Spray-drying was investigated for the stabilization of surfactant-free nanoparticles as carriers for dry-powder inhalers. The microparticles rapidly dissolve after inhalation yielding dispersed nanoparticles. Nanoparticles were prepared by a solvent displacement technique avoiding any surfactants.

Amine-modified poly(vinyl alcohol)s as non-viral vectors for siRNA delivery: effects of the degree of amine substitution on physicochemical properties and knockdown efficiency.

Purpose: The objective of this study was to investigate how the degree of amine substitution of amine-modified poly(vinyl alcohol) (PVA) affects complexation of siRNA, protection of siRNA against degrading enzymes, intracellular uptake and gene silencing.

Methods: A series of DEAPA-PVA polymers with increasing amine density was synthesized by modifying the hydroxyl groups in the PVA backbone with diethylamino propylamine groups using CDI chemistry. These polymers were characterized with regard to their ability to complex and protect siRNA against RNase.

Enhanced gene expression and reduced toxicity in mice using polyplexes of low-molecular-weight poly(ethylene imine) for pulmonary gene delivery.

The aim of this study was to elicit improved gene expression and decreased cytotoxicity for pulmonary gene therapy by replacing the commonly used carrier 25 kDa branched poly(ethylene imine) (BPEI) by two PEI derivatives, low-molecular-weight PEI (LMWPEI) and polyethylene glycol-grafted PEI (PEGPEI). All polymers were shown to condense DNA to spherical particles of approximately 100 nm. Biocompatibility was investigated in vitro and in vivo.

Diagnostic value of calculated testosterone indices in the assessment of polycystic ovary syndrome.

Background: One of the main criteria to establish a diagnosis of polycystic ovary syndrome (PCOS) is hyperandrogenemia. Recent observations suggest that total testosterone may not be a sensitive marker for the detection of androgen excess. The aim of the present study was to compare the value of different androgen determinations for diagnosis of PCOS.