Journal of Photochemistry and Photobiology最新文献

Significance: This study investigates the therapeutic potential of photobiomodulation (PBM) using visible and near-infrared (NIR) light on nitric oxide (NO) release from intact human skin. Given NO's critical role in physiological processes such as wound healing, inflammation control, and vasodilation, this research could lead to innovative non-invasive treatments.

Aim: The primary aim was to explore how PBM at different wavelengths affects NO release from human skin. Custom-built airtight sleeves equipped with gas ports were used to measure NO levels, assessing the impact of three specific wavelengths of light (455 nm, 660 nm, and 850 nm).

Approach: Eighteen healthy participants had their forearms enclosed in airtight sleeves. The skin was irradiated with the specified wavelengths at a fluence of 45 J/cm² and an irradiance of 50 mW/cm² for 15 min. NO levels were quantified after irradiation using chemiluminescence detection (CLD), which measures the chemiluminescent reaction of NO with ozone (O3) for real-time analysis.

Results: Significant differences in NO release were observed among the wavelengths tested, indicating that PBM stimulates NO release from intact human skin.

Conclusions: The study provides strong evidence that PBM using visible and NIR light can enhance NO release from human skin, suggesting potential therapeutic applications for conditions involving NO. Further research is needed to understand the mechanisms behind PBM-induced NO release and its clinical implications.

Phototoxicity plays an important role in tattoo toxicology due to the skin's daily exposure to sunlight and the permanent deposition of pigments in skin. Here, we investigated in chemico reactive oxygen species generation using 2′,7′-dichlorodihydrofluorescein diacetate and in vitro phototoxicity towards skin fibroblasts based on the OECD Test Guideline 432.

Proficiency substances, titanium dioxide (TiO₂, anatase 30 nm, anatase 100 nm, rutile 30 nm), pigment red 22 (PR 22) with and without purification and carbon black (CB) were investigated. Phototoxic properties of benzo[a]pyrene (B[a]P) were investigated with and without adsorption to CB. Pigments were characterised by dynamic light scattering.

All proficiency substances except for norfloxacin were predicted successfully and only TiO₂ anatase exhibited phototoxicity in the cell-based approach. B[a]P showed the expected phototoxicity in contrast to B[a]P bound to carbon black. Upon UVA irradiation, only TiO₂ pigment anatase and PR 22 generated ROS in the cell-free assay. DLS measurements showed a high degree of polydispersity/agglomeration.

OECD Test Guideline 432 should be applied with an incubation time of 24 h when testing highly insoluble pigments. The in chemico ROS assay introduced below might serve as a quick screening test but may be further adapted to predict the in vitro outcome.

Metal organic frameworks (MOFs) consist of metal atoms or clusters, coordinated to organic ligands to form macromolecular super structures, with pores large enough to host free drug molecules, including photodynamic therapy (PDT) photosensitizers. This review presents examples of applications in PDT of various types of MOFs. To contextualize the discussions of their PDT applications, general procedures of MOF synthesis are considered. Applications of MOFs in PDT are described using examples of several combination therapy innovations developed for the purpose of solving some of the key challenges in the clinical translation value chain of PDT. The review presents evidence to show that the explosion of research in MOFs is due to their capability for applications as carriers and delivery systems for PDT photosensitizers. It also shows their unique applications as platforms for combination therapies, for stimulus responsive release of photosensitizer and drug molecules, for cancer cell targeting, and for auxiliary enhancement of efficacy. Published literature on MOFs has been on the rise since the eighties. In Scopus, the applications of MOFs in PDT increased from 1 article in 2010, to 169 articles in 2023, whereas published literature on MOFs generally, increased from 878 to 11644 during this period. Research on the applications of MOFs in PDT has therefore increased more than that of MOFs generally. Literature on the applications of MOFs in PDT increased by between 0.7% to 1.45% relative to published literature on MOFs generally. Clearly, MOFs are researched to overcome challenges of and improve PDT efficacy, more than they are generally.

Solar energy is gradually becoming integrated into households, holding the potential to address energy requirements through technologies like PV cells. Ongoing research is actively exploring diverse methods of harnessing solar power, with Photogalvanic cells emerging as a particularly promising alternative to Photovoltaic cells. The advantage lies in the cost-effectiveness and simplified fabrication, coupled with the capability of power storage. The utilization of the economical Dioctyl sulfosuccinate sodium (DOSS) surfactant, widely employed in industry, has yielded impressive electrical performance. The present investigation presents a reliable photogalvanic system composed of the photosensitizer dye Quinoline Yellow, the reductant Cellobiose, and the surfactant Dioctyl sulfosuccinate sodium (DOSS), all in a highly alkaline solution with platinum and graphite electrodes. The platinum electrode employed is notably small, boasting a surface area of 0.03 cm², which enhances the diffusion characteristics of the dye molecules, it is contributing to an enhanced electrical performance of the photogalvanic cell. The resulting photogalvanic cell demonstrates superior electrical performance, featuring a maximum potential of 870 mV, a maximum current of 8000 µA, power at PowerPoint of 695 µW, a fill factor of 0.11, and a conversion efficiency of 13.78 %. Spectrophotometric analysis has confirmed the stability of the dye within the electrolyte solution. Additionally, conductometric analysis has revealed that the surfactant Dioctyl sulfosuccinate sodium (DOSS) enhances the electrical conductivity of the electrolyte solution.

Exposure to Ultraviolet B (UVB) radiation can trigger a diverse array of biological responses that have the potential to contribute to the onset of skin cancer. Natural compounds, such as tea polyphenols, have been shown to protect against UVB-induced damage by modulating oxidative stress, inflammatory response, and cell proliferation. The chemopreventive and anti-inflammatory properties of South African rooibos (Aspalathus linearis) and honeybush (Cyclopia spp.) herbal teas have been shown to mainly target the early stages of cancer development through mechanisms that involve intracellular interleukin-1α (IL-1α) inhibition. Thus, the aim was to investigate the preventive effects of unfermented rooibos and honeybush aqueous extracts against UVB-induced oxidative stress and inflammation in HaCaTs. Honeybush was found to reduce the accumulation of UVB-induced IL-1α while maintaining cell viability and without affecting apoptosis. Furthermore, only honeybush extract was able to decrease the secretion of interleukin-6 (IL-6) caused by UVB exposure. Honeybush and rooibos extracts significantly decreased the secretion of UVB-induced interleukin-8 (IL-8). Except for rooibos extract at a concentration of 0.2 mg/mL, both extracts restored the expression of antioxidant genes to levels observed prior to UVB exposure. The anti-inflammatory effects of these herbal tea extracts are likely attributed to the antioxidant properties of their polyphenolic constituents, which modulate the oxidative stress-induced pathways governing inflammatory responses.