We evaluated nine semi-transparent plastic window-tinting films for their ability to block ultraviolet A (UVA) and infrared (IR) radiation and transmit therapeutic blue light (400-520 nm) for treating jaundiced newborns. For indoor testing, three light sources (TL/52 special blue fluorescent, Black Light UVA and IR heat lamps) were positioned above each film and measured successively using a th...

UVA irradiation plays a role in premature aging of the skin through triggering oxidative stress-associated stimulation of matrix metalloproteinase-1 (MMP-1) responsible for collagen degradation, a hallmark of photoaged skin. Compounds that can activate nuclear factor E2-related factor 2 (Nrf2), a transcription factor regulating antioxidant gene expression, should therefore serve as effective an...

Many materials in everyday use such as window glass in homes and offices, glass in sunrooms and greenhouses, vehicle glass and some brands of sunscreens act as a barrier to the shorter UVB wavelengths while transmitting some of the longer UVA wavelengths. This paper reports on the erythemal exposures due to the UVA waveband encountered over a 12-month period for a solar zenith angle (SZA) range...

This article reviews the developments of 4⁃thiothymidine analogues, assisted with UVA light, as a novel cancer therapy. First, the key points on synthetic chemistry, photochemistry and cellular toxicity of 4⁃ thiothymidine are summarized. As the chemical structure of 4⁃thiothymidine is very similar to that of its parent thymidine, thus 4⁃thiothymidine can be readily incorporated into cellular D...

A. Environmental factors 1. Non-Ionizing Radiation – Ultraviolet (UVA & UVB) Two wavelength “types” of UV reach the earth’s surface – UVA (320-400nm) and UVB (290-320nm). Most of the UVB and all UVC are filtered by stratospheric ozone. UVA was initially thought to be noncarcinogenic, but is now thought to be a potent co-carcinogen with UVB. Recently, high dose UVA (as found in tanning beds) has...

Exposure to solar UVA (320-400 nm) radiation can damage DNA and lead to skin disorders. Conventional dosimetry using a single piece of polysulfone or diglycol carbonate (CR-39) cannot provide accurate measurement of the biologically effective irradiance for erythema for the UVA waveband. A package employing four dosimeters (polysulfone, nalidixic acid, 8-methoxypsoralen and phenothiazine) has b...

A 41-year-old man presented with a ten-year history of recurrent erythema and swelling of skin that occurred following sun exposure even as little as ten minutes. The lesion affected only on the sun exposed area. A phototesting was carried out and revealed that urticaria was induced following ultraviolet A (UVA) and visible light exposure. Solar urticaria (SU) from UVA and visible light was dia...

background: ultraviolet (uv) radiation is divided into three regions: uva, uvb, and uvc. both the quality and quantity of solar uv radiation vary with various factors including the elevation of the sun above the horizon, as well as absorption and scattering of uv photons by molecules in the atmosphere, notably ozone and clouds. it is clear that whereas a moderate amount of uv exposure is benefi...

During the summer months, from June thru September, in Opatija and island of Rab area, we conducted UVA and UVB measurements using a professional detector: Solar Light Co., Inc. USA. Ordering: PMA2110 UV-A and PMA2101 UV-B detector. We conducted global UVA and UVB measurements in the 2006 to 2011 period. Results of the measurements show June to September daily, 10 am to 3 pm, UVA and UVB variat...

We report that, in human skin, exposure to equally erythemogenic doses of UVA, UVB, and UVC increases immunocytochemically detected p53 in a wavelength-specific pattern. UVC produced immunostaining confined to the upper epidermis. With UVB, staining was seen throughout the epidermis, whereas with UVA staining predominated in the basal layer. The results with UVB and UVC are understandable on th...