The aim of the present study was to determine if human amnion‑derived mesenchymal stem cells (HAMSCs) exert a protective effect on ultraviolet A (UVA) irradiation-induced human dermal fibroblast (HDF) senescence. A senescence model was constructed as follows: HDFs (104‑106 cells/well) were cultured in a six‑well plate in vitro and then exposed to UVA irradiation at 9 J/cm2 for 30 min. Following...

Solar UVB is carcinogenic. Nucleotide excision repair (NER) counteracts the carcinogenicity of UVB by excising potentially mutagenic UVB-induced DNA lesions. Despite this capacity for DNA repair, non-melanoma skin cancers and apparently normal sun-exposed skin contain huge numbers of mutations that are mostly attributable to unrepaired UVB-induced DNA lesions. UVA is about 20-times more abundan...

Radiochromic film is tested for its broad-band response to ultraviolet (UV) B (290-320 nm) and A (320 nm400 nm), visible and infrared radiation produced by a solar simulator and examined for dosimetry in ultraviolet radiation. Results show that MD-55-2 radiochromic film in solar and fluorescent light sources responds almost exclusively to broad-band UVA radiation with negligible colouration fro...

To clarify the mechanism of long-term repetitive UVA irradiation in photoaging of the skin, we evaluated albino hairless (SKH: HR1) mice by the irradiation with UVA (300-420nm) for 12months. The output of irradiated UVA was 30J/cm2/day. Skin samples were taken from each group and examined at 0, 4, 8 and 12months. Morphologically, the structural changes of elastic fibers were observed in the der...

UVA irradiation (320-400 nm) comprises about 95 percent of incident midday solar ultraviolet irradiation. It penetrates skin much deeper than UVB irradiation. The absorption of UVA irradiation in endogenous chromophores frequently leads to the generation of reactive oxygen species such as singlet oxygen ((1)O(2)). (1)O(2) is an important biochemical intermediate in multiple biological processes...

With ultraviolet and visible light exposure, some pharmaceutical substances applied systemically or topically may cause phototoxic skin irritation. The major factor in phototoxicity is the generation of reactive oxygen species (ROS) such as singlet oxygen and superoxide anion that cause oxidative damage to DNA, lipids and proteins. Thus, measuring the generation of ROS can predict the phototoxi...

BACKGROUND Different investigation showed that 5-methoxypsoralen and 8- methoxypsoralen reduce birth rates in the rats. OBJECTIVE In this study we worked out the effect of methoxsalen together with ultraviolent A (UVA) radiation on mature Balb/C mice spermatogenesis. MATERIALS AND METHODS The LD50 standard was determined 160 mg/kg and the UVA dose which causes erythema was calculated 0.046 ...

In contrast to the immunosuppressive potential of UVB (280-320 nm) radiation in experimental animals and humans, UVA (320-400 nm) radiation at environmentally relevant doses appears to be immunologically inert. However, such exposure to UVA radiation has been observed unexpectedly to induce resistance to UVB-induced immunosuppression in mice, by a mechanism resulting in the inactivation of cis-...

purpose : to compare the protection of eyes against visible light (vl) and ultraviolet radiation (uvr) by sunglasses available through the iranian optician trade ::::union:::: (iotu) shops and those provided by miscellaneous vendors. methods : totally, 353 pairs of sunglasses, including 188 pairs from iotu shops and 165 pairs from miscellaneous vendors were selected based on systematic random s...