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The present work provides a novel contribution to the psychoanalytic literature on criminal tendencies and is based on an experience of group supervision with the staff of professionals in an Itali...

In this work, the potential in drug nanodelivery of micelles made from poly(ϵ-caprolactone) (PCL) and poly (ethyleneoxide) (PEO) copolymers with triblock and star-diblock architectures was explored. Linear and 4-arm star-shaped PCL macromers with two or four OH end groups were prepared by ring-opening polymerization of CL and condensed with α-methoxy-ω-carboxy-PEO. The resulting amphiphilic copolymers were characterized by 1H NMR, size exclusion chromatography, and differential scanning calorimetry. Separate PCL and PEO crystalline phases were observed for both copolymers. Copolymers self-assembled in water giving critical association concentrations in the range 0.010–0.023 mg/mL. Micelles with a size of 32–45 nm were prepared by dialysis and characterized for hydrodynamic diameter and surface charge. Their potential as nanocarriers in drug delivery applications was evaluated too. Micelles were nontoxic to both Red blood cells and HeLa cells. Complement activation experiments indicated that micelles can escape the reticuloendothelial system once intravenously injected. Finally, a different uptake on HeLa cells was found for micelles obtained from triblock and star-shaped copolymers. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res, 2008

The aim of this work was to design injectable nanocarriers for drug delivery based on PCL-PEO amphiphilic block copolymers with linear ABA triblock and 4-armed (BA)(4) star-diblock architectures (A=PEO, B=PCL). The copolymers were obtained by coupling of a monofunctional -COOH end-capped PEO (M(n)=2.0kDa) with linear or 4-armed star-shaped PCL macromers bearing -OH terminal groups and were characterized by (1)H NMR spectroscopy and size exclusion chromatography. DSC and X-ray diffraction experiments showed that separate crystalline phases of PCL and PEO are present in bulk copolymers. Nanoparticles were produced by nanoprecipitation (NP) and by a new melting-sonication procedure (MS) without the use of toxic solvents, and characterized for size, polydispersity, zeta potential and core-shell structure. Nanoparticles were loaded with all-trans-retinoic acid (atRA) as a model drug and their release features assessed. Results demonstrate that both techniques allow the formation of PEO-coated nanoparticles with a hydrodynamic diameter that is larger for nanoparticles prepared by MS. atRA is released from nanoparticles at controlled rates depending on size, loading and, more important, preparation technique, being release rate faster for MS nanoparticles. Some biorelevant properties of the carrier such as complement activation were finally explored to predict their circulation time after intravenous injection. It is demonstrated that nanoparticles prepared by MS do not activate complement and are of great interest for future in vivo applications.