We show for the first time that preferential damage of MRT to tumor vessels versus preservation of radioresistant normal brain vessels contributes to the efficient palliation of 9L gliosarcomas in rats. Molecular pathways of repair mechanisms in normal and tumoral vascular networks after MRT may be essential for the improvement of such differential effects on the vasculature.

Ultrasmall gadolinium-based nanoparticles (GBNs) induce both a positive contrast for magnetic resonance imaging and a radiosentizing effect. The exploitation of these characteristics leads to a greater increase in lifespan of rats bearing brain tumors since the radiosensitizing effect of GBNs can be activated by X-ray microbeams when the gadolinium content is, at the same time, sufficiently high in the tumor and low in the surrounding healthy tissue. GBNs exhibit therefore an interesting potential for image-guided radiotherapy.

Microemulsions are physically stable oil/water systems that have potential use as delivery systems for many pharmaceuticals which are normally of limited use due to their hydrophobicity, toxicity or inability to access the site of action. It has been suggested that microemulsions are self‐preserving antimicrobials in their own right, although there is little evidence to support this. In this experiment, microemulsions of various compositions were formulated and tested for their stability and antimicrobial action. The physical stability of the different microemulsions was assessed by centrifugation at 4000 g and by storage in a water bath at 37 °C for one month, during which no phase separation was observed. The antimicrobial activity of the microemulsions was tested using the compendial method, observation of the kinetics of killing, and transmission electron microscopy (TEM) of microemulsion‐exposed cultures of Pseudomonas aeruginosa PA01. These latter experiments on Ps. aeruginosa indicated distinct signs of membrane disruption. The results indicated that the microemulsions are self‐preserved, and that their killing of microbial cultures is very rapid and may be the result of membrane activity.

Herein, a library of gold nanorods (GNR) decorated with polyethylene glycol-thiol (PEG-SH) containing different functionalities were synthesized and characterized by optical absorption spectroscopy, zeta potential, dynamic light scattering (DLS), transmission electron microscope (TEM) and proton nuclear magnetic resonance ( 1 H-NMR). The colloidal stability of GNR when exposed to skin, and their preferential accumulation into excised human skin layers were investigated. Confocal laser scanning microscopy, transmission electron microscope (TEM) and inductively coupled plasma-optical emission spectroscopy (ICP-OES) were utilized to track the penetration of GNR into different skin layers. The results demonstrated that cholesterol-PEG coated GNR were preferentially loaded up in the upper layers of skin (stratum corneum), while phospholipid-PEG coated counterparts were drastically deposited in skin dermis. Neutral methoxy-PEG-coated GNR were distributed in both SC and dermis skin layers, while charged GNR (anionic-carboxylic acid-PEG-GNR and cationic-amine-PEG-GNR) revealed a minimal accumulation into skin. DSPE-PEG-GNR and Chol-PEG-GNR demonstrated antibacterial activities against Staphylococcus aureus ( S aureus ) at MIC values of 0.011 nM and 0.75 nM, respectively. Photothermal treatment for S. aureus at sub-MIC concentrations resulted in a significant bactericidal effect when using Chol-PEG-GNR but not DSPE-PEG-GNR. Gold-based nanoscale systems have great value as a promising platform for skin diseases therapy.

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