| 1. |
- Galichanin, Konstantin, et al.
(författare)
-
Upregulation of GADD45a, TP53 and CASP3 mRNA expression in the rat lens after in vivo exposure to sub-threshold exposure to UVR B
- 2014
-
Ingår i: Journal of Ocular Biology. - 2334-2838. ; 2:1, s. 5-
-
Tidskriftsartikel (refereegranskat)abstract
- Purpose:The objective of the present study was to investigate the evolution of mRNA expression of the stress sensor GADD45α, the apoptosis initiator TP53 and the apoptosis executor CASP3 in the rat lens after in vivo exposure to sub-threshold dose of UVR-B.Methods:Forty six-week-old female albino Sprague-Dawley rats were unilaterally exposed to a sub-threshold dose, 1 kJ/m2 (1.1 W/m2 for 15 min), of UVR (λmax = 300 nm). Anesthetized and dilated eyes were exposed to UVB radiation. The animals were sacrificed at 1, 5, 24 and 120 h post-exposure. mRNA expression of the GADD45α, TP53 and CASP3 genes in the lenses was measured by quantitative RT‑PCR, and fold change in mRNA expression between exposed and unexposed lenses was calculated.Results:mRNA expression for GADD45α increased to a 1.2 fold change at 1 h after exposure and then returned to no change at 120 h. mRNA expression for TP53 increased with a regression coefficient of 0.04 h-1 to a maximum of 1.67 fold change. mRNA expression for CASP3 increased with a regression coefficient of 4.5 x10-3 rel. units/h to a 1.46 fold change at 120 h after exposure.Conclusions:A sub-threshold in vivo exposure to UVR-B causes a transient upregulation of the stress sensor GADD45α at 1 h after exposure, a saturating upregulation of TP53 and a subsequent constant upregulation of CASP3 in the rat lens.
|
|
| 2. |
- Kronschläger, Martin, et al.
(författare)
-
Caffeine eye drops protect against UV-B cataract
- 2013
-
Ingår i: Experimental Eye Research. - : Elsevier BV. - 0014-4835 .- 1096-0007. ; 113, s. 26-31
-
Tidskriftsartikel (refereegranskat)abstract
- The purpose of this study was to investigate if topically applied caffeine protects against in vivo ultraviolet radiation cataract and if so, to estimate the protection factor. Three experiments were carried out. First, two groups of Sprague-Dawley rats were pre-treated with a single application of either placebo or caffeine eye drops in both eyes. All animals were then unilaterally exposed in vivo to 8 kJ/m(2) UV-B radiation for 15 min. One week later, the lens GSH levels were measured and the degree of cataract was quantified by measurement of in vitro lens light scattering. In the second experiment, placebo and caffeine pre-treated rats were divided in five UV-B radiation dose groups, receiving 0.0, 2.6, 3.7, 4.5 or 5.2 kJ/m(2) UV-B radiation in one eye. Lens light scattering was determined after one week. In the third experiment, placebo and caffeine pre-treated rats were UV-B-exposed and the presence of activated caspase-3 was visualized by immunohistochemistry. There was significantly less UV-B radiation cataract in the caffeine group than in the placebo group (95% confidence interval for mean difference in lens light scattering between the groups = 0.10 +/- 0.05 tEDC), and the protection factor for caffeine was 1.23. There was no difference in GSH levels between the placebo- and the caffeine group. There was more caspase-3 staining in UV-B-exposed lenses from the placebo group than in UV-B-exposed lenses from the caffeine group. Topically applied caffeine protects against ultraviolet radiation cataract, reducing lens sensitivity 1.23 times.
|
|
| 3. |
- Kronschläger, Martin, et al.
(författare)
-
Evolution of TUNEL-labeling in the Rat Lens After In Vivo Exposure to Just Above Threshold Dose UVB
- 2013
-
Ingår i: Current Eye Research. - : Informa UK Limited. - 0271-3683 .- 1460-2202. ; 38:8, s. 880-885
-
Tidskriftsartikel (refereegranskat)abstract
- Purpose/Aim:To quantitatively analyse the evolution of TUNEL-labeling, after in vivo exposure to UVB.Methods:Altogether, 16 Sprague Dawley rats were unilaterally exposed in vivo for 15 min to close to threshold dose, 5 kJ/m(2), of ultraviolet radiation in the 300nm wavelength region. Animals were sacrificed in groups of 4 at 1, 5, 24 and 120 h after exposure. For each animal, both eye globes were removed and frozen. The frozen eye was cryo-sectioned in 10 mm thick midsagittal sections. From each globe, three midsagittal sections with at least five sections interval in between were mounted on a microscope slide. Sections were TUNEL-labeled and counter stained with DAPI. For quantification of apoptosis, a fluorescence microscope was used. In sections with a continuous epithelial cell surface, the number of lens epithelial cell nuclei and the number of TUNEL-positive epithelial cell nuclei was counted. The total number of TUNEL-positive epithelial cell nuclei for all three sections of one lens in relation to the total number of epithelial cell nuclei for all three sections of the same lens was compared between exposed and contralateral not exposed lens for each animal.Results:The relative difference of the fraction of TUNEL-positive nuclei between exposed and contralateral not exposed lens increased gradually, peaked in the time interval 5-120 h after exposure, and then declined.Conclusions:Close to threshold dose of UVB induces TUNEL-labeling that peaks in the time window 5-120 h after exposure to UVB.
|
|
| 4. |
- Kronschläger, Martin, et al.
(författare)
-
Pharmacokinetics for topically applied caffeine in the rat
- 2014
-
Ingår i: Experimental Eye Research. - : Elsevier BV. - 0014-4835 .- 1096-0007. ; 122, s. 94-101
-
Tidskriftsartikel (refereegranskat)abstract
- Topically applied caffeine was recently identified as a promising candidate molecule for cataract prevention. Little is known about the pharmacokinetics for topically applied caffeine. Potential toxicity of 72 mM caffeine on the ocular surface and the lens was qualitatively monitored and no toxic effects were observed. The concentration of caffeine was measured in the lens and the blood after topical application of 72 mM caffeine to groups of 10 animals sacrificed at 30, 60, 90 and 120 min after topical application. The lens concentration decreased throughout the observation period while the blood concentration increased up to 120 min. Further, the concentration of caffeine in the lens and blood was measured 30 min after topical application of caffeine, the concentration of caffeine being 0.72, 3.34, 15.51 and 72 mM depending on group belonging, in groups of 10 animals. The caffeine concentration in lens and blood, respectively, increased proportionally to the caffeine concentration topically applied. The rat blood concentrations achieved were far below the equivalent threshold dose of FDA recommended daily dose for humans. This information is important for further development of caffeine eye drops for cataract prevention.
|
|
| 5. |
- Kronschläger, Martin, et al.
(författare)
-
Topically applied caffeine induces miosis in the ketamine/xylazine anesthetized rat
- 2014
-
Ingår i: Experimental Eye Research. - : Elsevier BV. - 0014-4835 .- 1096-0007. ; 127, s. 179-183
-
Tidskriftsartikel (refereegranskat)abstract
- The aim of the present study was to examine if topically applied caffeine influences pupil size in ketamine/xylazine anesthetized animals. Two experiments were carried out. In the first experiment, caffeine was topically applied to one of the eyes of 10 ketamine/xylazine anesthetized animals, while vehicle only was topically applied to the contralateral eye. In the second experiment, caffeine was topically applied to both eyes in one group of 10 ketamine/xylazine anesthetized rats, while in another group both eyes vehicle only was topically applied to both eyes. In both experiments pupil diameter was measured at 0, 10, 20, 40 and 60 min after topical application. In three of the animals, the pupil was dilated with tropicamide 5 mg/ml at 60 min after the topical application of caffeine and the pupil diameter was measured. The first experiment showed a relative miosis in caffeine treated eyes as compared to the vehicle treated eye, that changed over time. The second experiment in line with the first experiment, also showed that topically applied caffeine causes a relative miosis as compared to vehicle only that changes over time. Eyes treated with caffeine reacted with quick dilatation after tropicamide application. Topical caffeine antagonizes ketamine/xylazine anesthesia induced mydriasis in a time dependent manner.
|
|
| 6. |
- Steinvall, Ove, et al.
(författare)
-
Laser dazzling impacts on car driver performance
- 2013
-
Konferensbidrag (refereegranskat)abstract
- A growing problem for the Police and Security Forces has been to prevent potentially hostile individuals to pass a checkpoint, without using lethatl violence. Therefore the question has been if there is a laser or any other strong light source that could be used as a warning and dazzling device, without lethal or long term effects. To investigate the possibilities a field trial has been performed at a motor-racing track. A green CW laser with an irradiance on the eye of maximum 0.5 MPE, as defined by ICNIRP [1] and the ANZI standard [2], was used as a dazzle source. Ten drivers have been driving with dipped headlights through a course of three lines with orange cones. In every line there has been only one gate wide enough to pass without hitting the cones. The time through the course, the choice of gates and the number of cones hit have been measured. For every second trial drive through the track, the driver was exposed to the laser dazzler. The background illuminances ranged from a thousand lux in daylight to about ten millilux in darkness. The protective effect of the sun-visor of the car was investigated. The drives visual system was carefully examined before and after experimental driving and a few weeks after the experimental driving to verify that no pathological effects, that could potentially be induced by the laser exposure, pre-existed or occurred after the laser exposure. An analysis of variance for a within subjects design has been used for evaluation. It was found that green laser light can have an obvious warning effect in daylight. Dazzling does reduce the drivers ability to make judgments and manouver the car in twilight and darkness. A sun-visor can reduce the glare and give the driver an improved control, but that perception can be unjustified. No damage to the visual system was observed.
|
|
| 7. |
- Talebizadeh, Nooshin, 1977-, et al.
(författare)
-
Modelling the time evolution of active caspase-3 protein in the rat lens after in vivo exposure to Ultraviolet radiation-B : Model for active caspase-3 expression after in vivo exposure to UVR-300 nm
- 2014
-
Ingår i: PLOS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 9:9, s. e106926-
-
Tidskriftsartikel (refereegranskat)abstract
- Purpose: To introduce a model for the time evolution of active caspase-3 protein expression in albino rat lens up to 24 hours after in vivo exposure to low dose UVR in the 300 nm wavelength region (UVR-300 nm).Methods: Forty Sprague-Dawley rats were unilaterally exposed in vivo to 1 kJ/m2 UVR-300 nm for 15 minutes. At 0.5, 8, 16, and 24 hours after the UVR exposure, the exposed and contralateral not-exposed lenses were removed and processed for immunohistochemistry. The differences in the probability of active caspase-3 expression at four different time points after exposure were used to determine the time evolution of active caspase-3 expression. A logistic model was introduced for the expression of active caspase-3. The parameters for the exposed and the not exposed lenses were estimated for the observation time points.Results: The exposure to UVR-300 nm impacted on the parameters of the logistic model. Further, the parameters of the model varied with time after exposure to UVR-300 nm.Conclusion: The logistic model predicts the impact of exposure to UVR-300 nm on the spatial distribution of probability of active caspase-3 protein expression, depending on time.
|
|
| 8. |
- Talebizadeh, Nooshin, 1977-, et al.
(författare)
-
Specific spatial distribution of caspase-3 in normal lenses
- 2014
-
Ingår i: Acta Ophthalmologica. - : Wiley. - 1755-375X .- 1755-3768. ; 93:3, s. 289-292
-
Tidskriftsartikel (refereegranskat)abstract
- PurposeTo determine the distribution of active caspase-3 in rat eye lens epithelium.MethodsIn total, 120 sagittal sections from forty rats were assessed for active caspase-3 labelling using immunohistochemistry. Lens epithelial cells were counted, and the fraction of active caspase-3 labelled cells and their relative positions were identified in each section.ResultsActive caspase-3 is present in normal lens epithelium. The active caspase-3 expression was higher in the anterior pole of the lens. Probability of radial spatial distribution of labelling was fitted with a logistic model. The increase rate and the inflection point were estimated as CI (0.95) to 23 ± 3 cells and 114 ± 3 cells, respectively.ConclusionThe gradually decreasing active caspase-3 labelling from the anterior pole to the periphery suggests that active caspase-3 may be involved in normal protein turnover caused by, for example, incident light.
|
|
| 9. |
- Talebizadeh, Nooshin, et al.
(författare)
-
Time evolution of active caspase-3 labelling after in vivo exposure to UVR-300 nm
- 2014
-
Ingår i: Acta Ophthalmologica. - : Wiley. - 1755-375X .- 1755-3768. ; 92:8, s. 769-773
-
Tidskriftsartikel (refereegranskat)abstract
- PURPOSE:To determine the time evolution of active caspase-3 protein expression in albino rat lens after in vivo exposure to low-dose UVR-300 nm, as detected by immunofluorescence.METHODS:Forty Sprague-Dawley rats were unilaterally exposed in vivo to 1 kJ/m2 UVR-300 nm for 15 min. At 0.5, 8, 16 and 24 hr after the UVR exposure, the exposed and contralateral nonexposed lenses were removed and processed for immunohistochemistry. Three mid-sagittal sections from each lens were stained. The cells labelled for active caspase-3 in each section of both the exposed and nonexposed lenses were counted and recorded three times. The difference of the proportion of labelling between the exposed and contralateral nonexposed lenses within each animal was calculated. The differences of active caspase-3 labelling at four different time-points after exposure were used to determine the time evolution of active caspase-3 expression.RESULTS:Caspase-3 expression was higher in the exposed than in contralateral nonexposed lenses. The mean difference between the exposed and contralateral nonexposed lenses, including all lenses from all time intervals, was 0.12 ± 0.01 (= CI 95%). The mean differences between the exposed and contralateral nonexposed lenses were 0.11 ± 0.02, 0.13 ± 0.02, 0.14 ± 0.01 and 0.09 ± 0.03 (= CI 95%) for the 0.5-, 8-, 16- and 24-hr time groups, respectively. The orthogonal comparison showed no difference in the expression of active caspase-3 between the 0.5- and the 24-hr groups (Test statistic 1.50, F1,36 = 4.11, p < 0.05) or between the 8- and the 16-hr groups (test statistic 0.05, F1,36 = 4.11, p < 0.05). There was a difference when comparing the 0.5- and 24-hr groups to the 8- and 16-hr groups (test statistic 7.01, F1,36 = 4.11, p < 0.05).CONCLUSION:The expression of active caspase-3 in the lens epithelium increases after UVR exposure. There is a peak of expression approximately 16 hr after the exposure.
|
|
| 10. |
- Yu, Zhaohua, 1983-, et al.
(författare)
-
Green light laser exposure at 532nm near the exposure limit during a human volunteer vehicle driving task does not alter structure or function in the visual system
- 2014
-
Ingår i: Journal of laser applications. - Melville : Laser Institute of America. - 1042-346X .- 1938-1387. ; 26:2, s. 022009-1-022009-7
-
Tidskriftsartikel (refereegranskat)abstract
- This study aimed to verify nonexistence of clinically important pathological effects to the visual system after exposure to 532 nm green laser light close to the exposure limit. The present medical surveillance of vision and visual health reported in this paper is the conjunction with a study of driver performance in the presence of 532 nm laser induced glare. The driving time varied between 25 and 55 s, depending on background luminance. The laser was on during the complete test drive. The peak corneal irradiance typically was 3.5Wm2 in one test drive. Considering a typical test drive, the typical time integrated corneal radiant exposure for one test drive was estimated to be 53 J/m2. The number of test drives varied among drivers but was typically 50, thus resulting in a cumulative corneal exposure dose of approximately 2.7 kJ/m2. Altogether, ten subjects were recruited according to inclusion and exclusion criteria. All ten subjects were examined for visual acuity, intraocular pressure, contrast sensitivity, color vision, monocular reading speed, and eye structure with clinical slit-lamp microscopy examination and indirect retinoscopy. All subjects were examined before exposure, immediately after exposure, and finally within an interval between 1 week and 4 weeks after exposure. There was no significant change of visual acuity, intraocular pressure, contrast sensitivity, color vision, or monocular reading speed between before and after exposure. No abnormal ocular structure was detected after exposure. This study demonstrates that close to exposure limit, exposure to 532 nm green laser light during a vehicle driving task does not induce structural or functional damage to the human visual system as observed in the interval minutes to weeks after exposure.
|
|
