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Background: Cells have complex network of antioxidant enzymes that protect cells from induced damages by reactive oxygen species (ROS). Catalase and superoxide dismutase are known for their role as primary protection against oxidative stress. Oxidative damage is an important risk factor in age-related macular degeneration disease (AMD). For the first time in this study the impact of genetic polymorphisms of SOD1 and CAT with AMD has been examined. Hence, the association between genetic polymorphisms of catalase (CAT) C-262T, Cu/Zn superoxide dismutase (SOD1) A251G and risk of exudative AMD has been investigated. Methods: This study was carried out on blood samples collected from 112 exudative AMD patients and 112 healthy individuals. Genotyping of CAT C-262T and SOD1A251G was done by polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP) method. Differences in the frequencies were estimated using the χ2 test and risk was estimated with a logistic regression after adjusting for smoking, working place and age status. Results: There was significant difference between CAT CT+TT genotype and AMD disease (P=0.009, OR=0.38, 95%CI=0.18-0.78). Also T-allele has a significant association with risk of AMD and decreases risk of disease (P=0.036, OR=0.59, 95%CI=0.36-0.96), but there was no significant differences between SOD1A251G and variant homozygous and heterozygous frequencies in patients compared to controls (P=0.589, OR=0.77, 95%CI=0.3-1.96). Conclusions: The data presented suggest that the T-allele in CAT genotypes can increase catalase expression and activity, as a result of which generation of reactive oxygen species (ROS) can be decreased. Therefore it is suggested that increased expression of CAT as a result of T-allele in CAT genotypes and existence of T-allele in CAT genotypes is associated with decreased risk of AMD.

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Aims: Age-Related Macular Degeneration (AMD) is one of the biggest causes of vision loss after 50 years of age in the world. AMD disease destroys the retinal pigment cells. Retinal tissue engineering provides a suitable environment for the growth of retinal pigment epithelium cells using different scaffolds. These scaffolds may cause interior pressure changes in eyes and thus, causes disease of the separation of pigment and retinal epithelial cells. Therefore, the purpose of this study was to simulate gelatin, gelatin-chitosan and poly-caprolactone scaffolds in the retina and compare the pressure gradient and the effect of thickness on the pressure gradient.
Materials & Methods: In the present experimental study, in the first stage, three gelatin, gelatin-chitosan and poly-caprolactone scaffolds were simulated to examine the average scaffold pressure using COMSOL 5.1.1 software and Darcy law. In the next step, a gelatin-chitosan scaffold with thicknesses of 10 and 20 micron was simulated with Darcy law, to examine the effect of thickness on average pressure.
Findings: The output pressure of the gelatin scaffold was calculated as 308.800Pa Which was less than the pressure level of the caroid layer And it was less than the output pressure of other scaffolds. The average pressure of gelatin-chitosan scaffold with thicknesses of 10 and 20 micron was 1997.31 and 2003.13 respectively in the last step.
Conclusion: The gelatin scaffold produces a moderate lower pressure than the gelatin-chitosan scaffold and poly-caprolactone in the retina and it is more suitable than other scaffolds. In the simulation of gelatin-chitosan scaffold, increasing the thickness causes increased pressure and retinal impairment.