Effects of ultraviolet irradiation on corneal epithelium: Mitosis, nuclear fragmentation, post‐traumatic cell movements, loss of tissue cohesion

Use of Ultraviolet Radiation in Microbiological Laboratories

“…Aerosols of S. indica. or S. marcescens were produced 'from 24-hour broth cultures by 1 D*VMI's Co. 40 To evaluate the effectiveness of UV air locks, air wasa'ampled for bacterial content by sieve-type air samplers (Figure 37) with the UV lamps off and on. In some instances liquid impinger samplers were used for the UV off air samples, The comparative number of organisms recovered and the per cent reduction allowed an estimation of the effectiveness of the germicidal radiation.…”

“…Four-animals were exposed in a series, four times 24 hours apart, and the other two animals were exposed 40 times over a two month period, the minim~mi interval being 24 hours. Following exposure the eyes and ears of each animal were carefully examined at appropriate intervals for asustained period of time.…”

UVB‐induced formation of (6–4) photoproducts in the rat corneal epithelium

“…Several studies indicate that the (6-4) photoproduct is more mutagenic than the cyclobutane dimer (Franklin & Haseltine 1986;Glickman et al 1986;Tang et al 1986;Brash 1988;Mitchell et al 1990a). Polycromatic UV light inhibits the mitotic activity and leads to superficial nuclear fragmentation of the rat corneal epithelium (Buschke et al 1945). The mitotic rate and the DNA synthesis in the rat corneal epithelium are reduced after irradiation with UVB at 297 nm (Haaskjold et al 1993).…”

Sensitivity of the Cornea after Exposure to Ultraviolet Light

“…and the nucleic acids [12]. In addition, the deleterious effect of UV radiation is to (1) inhibit mitosis, (2) produce nuclear frag mentation, and (3) cause a loosening of the epithelial layer [1,13]. Obviously, the abio tic change may stop at any stage if the expo sure is mild, and in the present experiment it must have stopped at stage 2 and returned to normal.…”