Aqueous Humor Stimulates the Migration of Human Trabecular Meshwork Cells In Vitro

PURPOSE. Depletion of trabecular meshwork cell numbers is a feature of the outflow system in aging and in primary open-angle glaucoma. It is possible that migration stimulated by factors present in aqueous humor may contribute to the cell loss. This investigation assessed the chemoattractant potential of glaucomatous and nonglaucomatous human aqueous humor and fibronectin, one of its constituents, on a range of cultured trabecular meshwork cell lines. METHODS. Migration was assessed in 48-well modified Boyden chambers. The potential migratory stimulants were soluble fibronectin and glaucomatous and nonglaucomatous aqueous humor. The glaucomatous aqueous samples were collected from patients undergoing trabeculotomy for primary open-angle glaucoma and the normal aqueous from normal bovine eyes and patients undergoing cataract surgery. The target cell types were normal human and bovine meshwork cells grown from explants and two human transformed meshwork cell lines from a normal (HTM-5) and a glaucomatous (HTM-3) source

Bandage contact lens and topical steroids are risk factors for the development of microbial keratitis after epithelium-off CXL

Objective:To investigate the role of bandage contact lenses (BCL) and topical steroids as risk factors for the development of microbial keratitis after epithelium-off corneal collagen cross-linking (CXL). Methods and Analysis:Patients undergoing CXL between February 2011 and July 2017 were included. Patients were divided into two groups: those who were treated postoperatively with a BCL, topical antimicrobial and steroids (group 1) and those who received only a topical antimicrobial until healing of the epithelial defect before introduction of topical steroids (group 2). Results:1273 eyes of 964 patients were included. Group 1 comprised 316 eyes and group 2 comprised 957 eyes. There were no significant differences in the presence of persisting corneal haze or scarring between the two groups (p=0.57). Microbial keratitis occurred in nine eyes (0.71% of eyes) of eight (0.83%) patients (one case was bilateral) out of 1273 eyes. Staphylococcus aureus was cultured from corneal scrapes in seven out of nine (77.8%) cases and from contiguous sites in the two cases. All cases occurred in group 1 (incidence=2.85%) and none in group 2 (p<0.0001). A greater proportion of patients who developed microbial keratitis were atopic (75%, p=0.4). Conclusion:The use of BCL and topical steroids prior to healing of the epithelium is a significant risk factor for microbial keratitis. S. aureus is the most common micro-organism and is likely to originate from an endogenous site. Not using a BCL and delaying the introduction of topical steroids until epithelial healing significantly reduce the risk of developing microbial keratitis without increasing the risk of persistent corneal haze

Refractive outcomes following cataract surgery in patients who have had myopic laser vision correction.

ObjectivePrediction errors are increased among patients presenting for cataract surgery post laser vision correction (LVC) as biometric relationships are altered. We investigated the prediction errors of five formulae among these patients.Methods and analysisThe intended refractive error was calculated as a sphero-cylinder and as a spherical equivalent for analysis. For determining the difference between the intended and postoperative refractive error, data were transformed into components of Long's formalism, before changing into sphero-cylinder notation. These differences in refractive errors were compared between the five formulae and to that of a control group using a Kruskal-Wallis test. An F-test was used to compare the variances of the difference distributions.Results22 eyes post LVC and 19 control eyes were included for analysis. Comparing both groups, there were significant differences in the postoperative refractive error (p=0.038). The differences between the intended and postoperative refractive error were greater in post LVC eyes than control eyes (p=0.012), irrespective of the calculation method for the intended refractive error (pConclusionBiometry calculations were less precise for patients who had LVC than patients without LVC. No particular biometry formula appears to be superior among patients post LVC

Experiments in Globalisation, Food Security and Land Use Decision Making

The globalisation of trade affects land use, food production and environmentsaround the world. In principle, globalisation can maximise productivity andefficiency if competition prompts specialisation on the basis of productive capacity.In reality, however, such specialisation is often constrained by practical or politicalbarriers, including those intended to ensure national or regional food security.These are likely to produce globally sub-optimal distributions of land uses. Bothoutcomes are subject to the responses of individual land managers to economicand environmental stimuli, and these responses are known to be variable and often(economically) irrational. We investigate the consequences of stylised food securitypolicies and globalisation of agricultural markets on land use patterns under avariety of modelled forms of land manager behaviour, including variation inproduction levels, tenacity, land use intensity and multi-functionality. We find that asystem entirely dedicated to regional food security is inferior to an entirelyglobalised system in terms of overall production levels, but that several forms ofbehaviour limit the difference between the two, and that variations in land useintensity and functionality can substantially increase the provision of food and otherecosystem services in both cases. We also find emergent behaviour that results inthe abandonment of productive land, the slowing of rates of land use change andthe fragmentation or, conversely, concentration of land uses following changes indemand levels

Ophthalmology An Illustrated Colour Text

125 hal.;ill.; 28 c