Changes in Corneal Basal Epithelial Phenotypes in an Altered Basement Membrane

To examine the corneal epithelial phenotype in an altered basement membrane.Corneas from 9 patients with symptoms of continuous unstable corneal curvature (CUCC) were harvested by penetrating keratoplasty and subjected to histology examination and immunohistochemical staining with transactivating and N-terminally truncated pP63 transcript (ΔNp63), cytokeratin 3 (Krt3), ATP-binding cassette sub-family G member 2 (ABCG2), connexin 43 (CX43), p38 mitogen-activated protein kinases (p38MAPK), activating protein 2 (TFAP2), and extracellular signal-regulated kinase (Erk1/2) monoclonal antibodies. Positive immunostaining with ABCG2, p38MAPK, and TFAP2 monoclonal antibodies was observed in the basal epithelial cells of CUCC patients, and CX43 and ΔNp63 were detected in the full-thickness epithelial cells of CUCC patients.Our results indicate that alteration of the corneal basement membrane induces a de-differentiation-like phenotype in corneal basal epithelial cells

Activity Levels Related to Lunar Brightness and Diel Activity Patterns of Tapiridae and Felidae Species Across Neotropical Sites

Tapirs serve important ecological roles (e.g., as seed dispersers) and have serious conservation and management needs due to anthropogenic influences of their habitats. However, details of their ecology are not well understood as tapirs are difficult to study because of the secretive nature and usually low densities over wide areas. I used circular statistics and a null model approach to analyze a set of camera trap records (N= 8,889) from 16 sites in Central and South America. I examined the diel activity patterns and amount of activity along lunar phases for the Lowland tapir (Tapirus terrestris), Mountain tapir (Tapirus pinchaque), and Baird’s tapir (Tapirus bairdii), as well as for their main potential predators Jaguar (Panthera onca) and Puma (Puma concolor). For all species I used a null model approach to evince highly temporal coincident activity patterns among sites, thus allowing the examination of activity using a wider scope, instead of a site based traditional approach. Most species showed trends for nocturnal activity patterns although they had a heterogenous variation. Pairwise comparisons of activity patterns between Tapiridae and Felidae species indicated significant temporal partitioning. Baird’s and Lowland tapirs showed a preference for activity during relatively bright nights (waxing gibbous for both species) whereas Jaguar and Puma showed preference for the brightest nights in the lunar cycle (full moon in both cases). In conclusion, the high degree of temporal partitioning between Tapiridae and Felidae species suggests an avoidance of predators regardless of lunar brightness. Results also reveal strong evidence for similar activity patterns across broad geographical scales that allow for more biologically meaningful inferences to be made in relation to wildlife monitoring and conservation in the Neotropics.Biolog

Using optical coherence tomography to assess corneoscleral morphology after soft contact lens wear

Purpose. To evaluate the use of optical coherence tomography (OCT) to assess the effect of different soft contact lenses on corneoscleral morphology. Methods. Ten subjects had anterior segment OCT B-scans taken in the morning and again after six hours of soft contact lens wear. For each subject, three different contact lenses were used in the right eye on non-consecutive days, including a hydrogel sphere, a silicone hydrogel sphere and a silicone hydrogel toric. After image registration and layer segmentation, analyses were performed of the first hyper-reflective layer (HRL), the epithelial basement membrane (EBL) and the epithelial thickness (HRL to EBL). A root mean square difference (RMSD) of the layer profiles and the thickness change between the morning and afternoon measurements, was used to assess the effect of the contact lens on the corneoscleral morphology. Results. The soft contact lenses had a statistically significant effect on the morphology of the anterior segment layers (p <0.001). The average amounts of change for the three lenses (average RMSD values) for the corneal region were lower (3.93±1.95 µm for the HRL and 4.02±2.14 µm for the EBL) than those measured in the limbal/scleral region (11.24±6.21 µm for the HRL and 12.61±6.42 µm for the EBL). Similarly, averaged across the three lenses, the RMSD in epithelial thickness was lower in the cornea (2.84±0.84 µm) than the limbal/scleral (5.47±1.71 µm) region. Post-hoc analysis showed that ocular surface changes were significantly smaller with the silicone hydrogel sphere lens than both the silicone hydrogel toric (p<0.005) and hydrogel sphere (p<0.02) for the combined HRL and EBL data. Conclusions. In this preliminary study, we have shown that soft contact lenses can produce small but significant changes in the morphology of the limbal/scleral region and that OCT technology is useful in assessing these changes. The clinical significance of these changes is yet to be determined