UV radiation from sunlight is the most potent environmental risk factor in skin cancer pathogenesis. In the present study the ability of an algal extract to protect against UVA-induced DNA alterations was examined in human skin fibroblasts (1BR-3), human melanocytes (HEMAc) and human intestinal CaCo-2 cells. The protective effects of the proprietary algal extract, which contained a high level o...

AIM The purpose of this study was to characterise C₆₀-poly(vinylpyrrolidone) (PVP) dispersions, to analyse the cutaneous absorption of fullerenes as well as to evaluate whether UVA radiation (UVA-R) could modify its permeation profile. METHODS Dispersions were characterised according to their pH, particle size, zeta potential, and morphology. Skin absorption studies were performed using porci...

The vocal control system of zebra finches shows auditory gating in which neuronal responses to the individual bird's own song vary with behavioral states such as sleep and wakefulness. However, we know neither the source of gating signals nor the anatomical connections that could link the modulatory centers of the brain with the song system. Two of the song-control nuclei in the forebrain, the ...

Although there are numerous examples of animals having photoreceptors sensitive to UVA (315-400 nm) [1] and relying on UVA-based mate-choice cues [2-5], here we provide the first evidence of an animal using UVB (280-315 nm) for intraspecific communication. An earlier study showed that Phintella vittata, a jumping spider (Salticidae) from China, reflects UVB [6]. By performing six series of bina...

Background. UVA irradiation is one of the most ubiquitous and penetrating environmental stress factor to human skin and it is crucially involved in various forms of skin damages including the photoaging and development of cancer. Mentioned skin damages are connected mainly with imbalance in redox status and consequently with cellular metabolic disturbances including changes in phospholipid medi...

We previously developed a high powered light-emitting diode device capable of discharging germicidal ultraviolet irradiation (UVA-LED) at an approximate wavelength of 365 nm. This study examined the bactericidal activity of UVA-LED in moving air streams. Aerosols of Escherichia coli DH5alpha were exposed to UVA-LED irradiation using a stable current (0.5 A and 1.2 mW/cm(2)) or pulse current (1....

Ultraviolet (UV) irradiation is a major environmental carcinogen involved in the development of skin cancer. To elucidate the initial signaling during UV-induced damage in human keratinocytes, we investigated lysosomal exocytosis and apoptosis induction. UVA, but not UVB, induced plasma membrane damage, which was repaired by Ca(2+)-dependent lysosomal exocytosis. The lysosomal exocytosis result...

High-performance liquid chromatography (HPLC)-size exclusion chromatography (SEC) with ultraviolet absorbance (UVA) and on-line dissolved organic carbon (DOC) detectors has been adapted and optimized under various conditions. An enhanced HPSEC-UVA system employing a modified commercially available DOC detector provides a better understanding of the qualitative and quantitative natural organic m...

Although the biological importance of ultraviolet light (UVR) attenuation has been recognised in marine and freshwater environments, it is not generally considered in in vitro ecotoxicological studies using algal cell suspensions. In this study, UVA and UVB extinction were determined for cultures of algae with varying cell densities, and the data were used to calculate the corresponding extinct...

UV radiation belongs to the non-ionizing part of the electromagnetic spectrum and ranges between 100 nm and 400 nm; 100 nm has been chosen arbitrarily as the boundary between nonionizing and ionizing radiation. UV radiation is conventionally categorized into 3 regions: UVA (>315–400 nm), UVB (>280–315 nm) and UVC (>100–280 nm) (Figure 1). These categories have been confirmed by the Commission I...