Doxorubicin Intracellular Release Via External UV Irradiation of Dextran-g-poly(o-nitrobenzyl acrylate) Photosensitive Nanoparticles.

In the present study, innovative doxorubicin-loaded nanoparticles (NPs) made of a photosensitive poly(o-nitrobenzyl acrylate) (PNBA) hydrophobic matrix and an hydrophilic dextran (Dex) shell were first formulated by the emulsion-solvent evaporation process. Doxorubicin (DOX), a very well-known anticancer drug, was herein chosen as the model. DOX-loaded NPs were successfully produced by covering the hydrophobic PNBA core with Dex chains either physically adsorbed or covalently linked by changing process parameters as the presence of a catalyst (CuBr or CuSO4/ascorbic acid). It was then proved that the neutralization of DOX optimized drug loading. DOX loading and release were independent of the coverage mechanism if the catalyst used to covalently link the shell to the core was correctly chosen. Second, the kinetics of DOX release were investigated by simple diffusion or light irradiation of the NPs. Experiments showed that less than 20% of DOX was released by simple diffusion after 48 h in PBS or DMEM media when 45% of DOX released after only 30 s of light irradiation of the NPs. Finally, the impact of the phototriggered DOX release on cell viability was investigated on various cell lines [Caco-2, HepG2, HCT-116, and HT-29 cells as well as murine macrophages (RAW 264.7)]. Cellular mortality was evaluated to be dependent on the cell lines tested. Our approach provided an improved DOX release toward the human liver cancer cell line, and a high internalization of the PNBA-based NPs into HepG2 cells was observed using fluorescence microscopy.

Controlled trial evaluation of exposure duration to negative air ions for the treatment of seasonal affective disorder.

This study evaluated the effectiveness of 30 or 60min of daily exposure to high-density or to zero-density (placebo condition) negative air ions over 18 days on the symptoms of seasonal affective disorder (SAD) in 40 participants under controlled laboratory conditions. Exposure to high-density negative air ions was superior to zero-density negative air ions in alleviating depression and the atypical symptoms of SAD. Also, more subjects in the high-density negative air ions groups met two different clinical response criteria than did those in the zero-density groups. Within the high density treatment group, both the short and long daily exposure reduced SAD symptoms. Exposure to negative air ions produced no negative side effects, and no ozone was produced by the ion generators. In both the high-density negative air ions and zero-density negative air ions groups, a significant placebo effect was found for most clinical measures. Finally, for the high-density negative air ion groups, subjects with a morningness chronotype responded better to treatment with high-density negative air ions than did those with an eveningness chronotype.

A randomized, placebo-controlled trial of bright light and high-density negative air ions for treatment of Seasonal Affective Disorder.

This study, conducted over the course of 5 years, assessed the antidepressant efficacy of two active treatments, bright white light and high-density negative ions, and the efficacy of two placebo treatments, dim red light and low-density negative ions, for Seasonal Affective Disorder (SAD). In a controlled laboratory setting, 73 women with SAD were exposed to one of the four treatment conditions over 12 consecutive days. Pretreatment expectation ratings did not significantly differ among the four treatment groups; however, expectation scores and treatment benefits were positively related. Over the course of treatment, subjects in all four groups showed significant score decreases on the Structured Interview Guide for the Hamilton Depression Rating Scale-Seasonal Affective Disorder Version-Self Rating (SIGH-SAD-SR) and on the Beck Depression Inventory (BDI). For raw scale scores, neither main effects of treatment nor interactions between treatment and time were significant. When remission outcome criteria were used, bright white light was significantly more effective than any of the other three treatments, and exposure to high-density negative ions was more effective than either of the two placebo conditions, although the difference was not significant.