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The mutagenic potential of selected widely used pesticides: p,p'-dichlorodiphenyltrichloroethane (DDT); fenitrothion; propoxur; deltamethrin, bifenthrin; imidacloprid and thiametoxam was assessed using the wing spot test. Third-instar larvae of standard Drosophila melanogaster cross (ST), transheterozygous for the third chromosome recessive markers, multiple wing hairs (mwh) and flare (flr3) were chronically exposed to test compounds. Feeding ended with pupation of the surviving larvae. Genetic changes induced in somatic cells of the wing's imaginal discs, mutant spots observed in marker-heterozygous (MH) and balancer-heterozygous (BH) flies were compared using the wing spot test, to estimate the genotoxic effects of these pesticides. In conclusion, exposure to 30 mg/mL deltamethrin, 40 mg/mL imidacloprid, 100 μg/mL DDT showed mutagenic and recombinagenic effects in the Drosophila wing spot test. In addition the results of chronic treatments performed at high doses showed mutagenic and recombinagenic effects in both genotypes. [ABSTRACT FROM AUTHOR]

Refractive error is becoming a significant public health issue. Photorefractive Keratectomy (PRK) is a corneal surface surgical technique that removes the corneal epithelium before stromal photoablation by ultraviolet radiation from the Excimer laser. We designed a retrospective study to characterize corneal remodeling after myopic Photorefractive Keratectomy and assess the accuracy of laser-predicted ablation depth (AD). This study took place in 15-20 National Ophthalmology Hospital, Paris, France. 150 eyes with preoperative manifest spherical equivalent between - 10.00D and - 0.25D and cylinder < 3D, treated with the WaveLight® EX500 laser between 01/2019 and 01/2023, were followed for at least three months. The main outcome measurements were postoperative changes in epithelial (ET) and stromal (ST) thicknesses measured with spectral domain optical coherence tomography and mean simulated keratometry (SimK) assessed with corneal topography. The central ET significantly decreased at M1, increased over the preoperative value from M1 to M6, and stabilized after M6. The increase in central ET after M1 was associated with an increase in mean SimK (r = 0.34). The achieved AD was 7.9 ± 8.0 µm greater than the laser-predicted AD. Stromal over-ablation was significantly and independently associated with myopia > 6D preoperative mean SimK > 44D and transepithelial procedures., (© 2024. The Author(s).)

The aim of this study was to assess Corvis ST biomechanical indices in reference to corneal enantiomorphism. In a prospective observational cohort study, 117 eyes from 63 patients with normal or keratoconus corneas were assessed by three independent observers. In the control group (n = 62), no significant differences were observed between the three observers for all indices. The best reproducibility was obtained with pachymetry and the weakest with CBI. All indices but CBI and arc length featured COV < 10%. All indices except the PD and SSI correlated with pachymetry; all but Rad correlated with IOP. The comparison of the thinnest with the thickest corneas showed no significant differences for any index except pachymetry. In the keratoconus group (n = 55), loss of corneal enantiomorphism was confirmed for all indices except the arc length, velocity, and PD. Significant differences between both groups were found for all indices, even after adjustment for pachymetry and intraocular pressure. The CBI featured the best accuracy (92%), sensitivity (91%), and graphical relevance for keratoconus diagnosis. However, its reproducibility was weak in normal corneas and was strongly dependent on corneal thickness. The SSI was independent of corneal thickness, highly reproducible, and provided the expected enantiomorphism characteristics in both groups, making it a relevant biomarker of biomechanical corneal behavior.