Most targeting strategies of anticancer drug delivery systems (DDSs) rely on the surface functionalization of nanocarriers with specific ligands, which trigger the internalization in cancer cells via receptor-mediated endocytosis. The endocytosis implies the entrapment of DDSs in acidic vesicles (endosomes and lysosomes) and their eventual ejection by exocytosis. This process, intrinsic to eukaryotic cells, is one of the main drawbacks of DDSs because it reduces the drug bioavailability in the intracellular environment. The escape of DDSs from the acidic vesicles is, therefore, crucial to enhance the therapeutic performance at low drug dose. To this end, we developed a multifunctionalized DDS that combines high specificity towards cancer cells with endosomal escape capabilities. Doxorubicin-loaded mesoporous silica nanoparticles were functionalized with polyethylenimine, a polymer commonly used to induce endosomal rupture, and hyaluronic acid, which binds to CD44 receptors, overexpressed in cancer cells. We show irrefutable proof that the developed DDS can escape the endosomal pathway upon polymeric functionalization. Interestingly, the combination of the two polymers resulted in higher endosomal escape efficiency than the polyethylenimine coating alone. Hyaluronic acid additionally provides the system with cancer targeting capability and enzymatically controlled drug release. Thanks to this multifunctionality, the engineered DDS had cytotoxicity comparable to the pure drug whilst displaying high specificity towards cancer cells. The polymeric engineering here developed enhances the performance of DDS at low drug dose, holding great potential for anticancer therapeutic applications.

Neuronal alterations in five cases of multiple system atrophy (MSA) were investigated histologically, immunocytochemically and ultrastructurally. Argentophilic neuronal cytoplasmic inclusions (NCIs) were observed in all cases. They were distributed, in order of decreasing frequency, in the pontine nucleus, striatum, subiculum, amygdala, hippocampus, dentate fascia, substantia nigra and inferior olivary nucleus. Anti-ubiquitin antibodies visualized many thickened neurites in the degenerating gray matter as well as NCIs. Some NCIs were also recognized by anti-phosphorylated neurofilament antibodies. Ultrastructurally, NCIs consisted of a meshwork of granule-associated filaments, the diameter ranging from 18 to 28 nm, that were mixed with neurofilaments. The granule-associated filaments were also present in the axoplasm of myelinated fibers. Our studies demonstrate widespread distribution of NCIs in the central nervous system of MSA. The same pathological process that forms the granule-associated filaments in axons may also be responsible for the formation of ubiquitin-positive thickened neurites. These axonal alterations, as well as neuronal perikaryal changes, may play an important role in the impaired neuronal function in MSA.

A tetraphenylporphyrin based Tb(III) double-decker complex has been synthesized and the crystal structure of both protonated and deprotonated forms has been determined. The ac magnetic susceptibility measurements revealed that the SMM properties of the double-decker complex can be reversibly switched by only a single proton.

Oligodendroglial cytoplasmic inclusions (OCI) in multiple system atrophy were investigated immunocytochemically and ultrastructurally. Among the 17 cases examined, 16 had OCIs. Almost all OCIs were positive for both alpha B-crystallin and ubiquitin. The antibodies against tubulin, paired helical filament and tau stained OCIs to various extents. Ultrastructurally OCIs consisted of meshworks of granule-associated filaments about 25 nm in diameter that sometimes formed flame-shaped tangle-like structures. Immunoelectron microscopy showed that an epitope of alpha B-crystallin was located on the granule-associated filaments composing OCIs. Our studies further support a cooperative role of alpha B-crystallin, ubiquitin and cytoskeletal protein in the formation of some types of intracytoplasmic inclusions.

A simple and fast one-step fabrication method of silver nanoparticles (AgNPs) on a polydimethylsiloxane (PDMS) film and their improvement as highly sensitive surface enhanced Raman scattering (SERS) substrates via atomically thin Au coatings is demonstrated. The thin Au layer provides oxidation resistivity while maintaining the broad spectral range SERS sensitivity of Ag nanoparticles.

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A novel one-step in situ synthesis of gold nanostars (AuNSs) on a pre-cured polydimethylsiloxane (PDMS) film is proposed for the fabrication of highly sensitive surface-enhanced Raman scattering (SERS) substrates. Plasmonic activity of the substrates was investigated by collecting SERS maps of 4-mercaptobenzoic acid (4-MBA). The applicability of these flexible substrates is further demonstrated by SERS-based pesticide detection on fruit skin.

Double-decker complexes based on single-molecule magnets (SMMs) are a class of highly promising molecules for applications in molecular spintronics, wherein control of both the ligand oxidative states and the 2D supramolecular structure on carbon materials is of great importance. This study focuses on the synthesis and study of 2,3,7,8,12,13,17,18-octaethylporphyrin (OEP)-Tb(III) double-decker complexes with different electronic structures comprising protonated, anionic, and radical forms. Magnetic susceptibility measurements revealed that only the anionic and radical forms of the OEP-Tb(III) double-decker complexes exhibited SMM properties. The barrier heights for magnetic moment reversal were estimated to be 207 and 215 cm(-1) for the anionic and radical forms, respectively. Scanning tunneling microscopy (STM) investigations revealed that these OEP-Tb(III) complexes form well-ordered monolayers upon simple dropcasting from dilute dichloromethane solutions. All three complexes form an isomorphic pseudo-hexagonal 2D pattern, regardless of the differences in the electronic structures of their porphyrin-Tb cores. This finding is of interest for SMM technology as ultrathin films of these materials undergoing chemical transformations will not require any detrimental reorganization. Finally, we demonstrate self-assembly of the protonated 5,15-bisdodecylporphyrin (BDP)-Tb(III) double-decker complex as an example of successful supramolecular design to achieve controlled alignment of SMM-active sites.