RESUMO
PURPOSE: This study aimed to determine the effect of serum G receptor-mediated protein-1 levels on the development of retinopathy in patients with diabetes in comparison with healthy individuals. METHODS: The study enrolled patients with diabetic retinopathy (Group 1), patients without diabetic retinopathy (Group 2), and healthy individuals (Group 3). Levels of serum progesterone, serum G receptor-mediated protein-1, estradiol, oxidant/antioxidants, and thyroid-releasing hormones were analyzed and compared among the groups. Post-hoc analysis was performed to compare the subgroups in which significant differences were found. RESULTS: Groups 1, 2, and 3 each included 40 patients. A significant difference was found among all groups in terms of serum G receptor-mediated protein-1, oxidant/antioxidant, and estradiol levels (p<0.01), but no significant difference was found in terms of thyroid-releasing hormone or progesterone (p=0.496, p=0.220, respectively). In the post-hoc analysis of the groups with significant differences, another significant difference was found among all groups for serum G receptor-mediated protein-1 and oxidant/antioxidant levels (p<0.05). Serum G receptor-mediated protein-1 and oxidant levels were positively correlated, whereas serum G receptor-mediated protein-1 and antioxidant levels were negatively correlated (r=0.622/p<0.01, r=0.453/p<0.01, r=0.460/p<0.01, respectively). The multiple regression analysis showed that increased levels of serum G receptor-mediated protein-1 may help prevent diabetic retinopathy. CONCLUSIONS: Serum G receptor-mediated protein-1 levels, which were the highest in the diabetic retinopathy Group, increased as the oxidant/antioxidant balance changed in favor of oxidative stress. This appears to be a defense mechanism for preventing neuronal damage.
RESUMO
ABSRTACT: PURPOSE: To investigate the acute and chronic effects of the use of smokeless tobacco (Maras powder) on macular and choroidal blood flow, via optical coherence tomography angiography (OCTA). METHODS: The study included 30 eyes of 30 patients using smokeless tobacco (ST) as the study group and 30 eyes of 30 healthy individuals as the control group. All subjects underwent a full ophthalmological examination, and baseline OCTA measurements were taken. Flow area in superficial capillary plexus (SCP), in deep capillary plexus (DCP), in choriocapillaris (mm2) and mean vascular density (VD) and foveal avascular zone in SCP and in DCP were assessed. Subfoveal choroidal thickness (SFCT) and central macular thickness were measured as well. RESULTS: The SFCT measurements were determined to be significantly low in the study group (p < 0.001). In the comparison of the study group measurements at 5 m, 30 m and 1 h after using ST compared to the baseline measurements, SCP and DCP flow area, VD, CC flow area and SFCT were determined to have significantly decreased, statistically (p < 0.001). CONCLUSION: OCTA could be important in showing that choroidal microvascular structures have been affected before occurence of the apparent clinical signs associated with acute and chronic ST use.