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Objective Corneal ulcers are commonly encountered in pinnipeds. Prolonged oral antibiotics and topical ophthalmic solutions may not be practical to administer, and novel treatment techniques are desired. Thermodynamic gels are a potential solution because they hold antimicrobials at the site of injection, slowly releasing drug. This study investigated the clinical efficacy of antibiotic-impregnated poloxamer gel in management of corneal ulceration. Animal studied Twenty-six California sea lions undergoing rehabilitation at The Marine Mammal Center. Procedures A poloxamer gel mixed with 2% enrofloxacin was subconjunctivally injected in the treatment group. Control animals received oral doxycycline. Systemic anti-inflammatories and analgesics were administered as needed. Corneal examinations under general anesthesia were repeated weekly, and included sampling for bacterial culture and corneal cytology, collection of high-quality corneal images, and treatment administration until the ulcers were healed. Results There was no gross or histologic evidence of a localized tissue reaction to the gel administration in the conjunctiva, and no evidence of systemic reaction to therapy in animals that died due to unrelated causes during the study period ( n = 17). In animals that experienced a superficial corneal ulcer involving only epithelium or superficial stroma ( n = 12), all lesions resolved completely, in both treatment and control groups. Of those animals with deeper or more complex ulcers involving keratomalacia or descemetoceles ( n = 15), four demonstrated complete lesion resolution (all four received gel treatment). Conclusions This study demonstrates that subconjunctival antibiotic poloxamer gel administration is a safe and effective alternative therapeutic option to traditional treatments for superficial corneal ulceration in pinnipeds. [ABSTRACT FROM AUTHOR]

Objective Heat-shock proteins, particularly the 70- kDa member (Hsp70), have been implicated in facilitating wound healing in multiple tissues. Expression and localization of three HSPs were assessed in normal and wounded canine corneas to elucidate a role in epithelial healing. Methods Paraffin-embedded normal corneas, acute and repeatedly abraded corneas, and keratectomies of spontaneous chronic corneal epithelial defects ( SCCEDs) were subjected to routine immunohistochemistry for Hsp27, 47, and 70 expression. Ex vivo corneal defects were created and treated with anti- HSPs or IgG controls, and wound healing was monitored. Primary cultures of canine corneal stromal fibroblasts and corneal epithelial cells were treated with exogenous Hsp70, and an artificial wound was created in vitro to monitor restoration of the monolayer. Results Normal canine corneas exhibited constitutive expression of all HSPs evaluated. Inducible expression was demonstrated in acutely wounded tissues, and expression in the chronically abraded corneas was relocalized. All HSP expression was below the limits of detection in the epithelium of SCCED samples. Inhibition of HSPs in culture resulted in delayed wound healing when compared to controls. Hsp70-treated fibroblasts demonstrated significantly ( P < 0.001) increased migration and proliferation compared to the vehicle control; however, there was no significant effect of exogenous Hsp70 on corneal epithelial cells. Conclusions These findings suggest that HSPs are induced in the normal canine cornea during re-epithelialization. Hsp70 expression is likely important for inducing the cytoarchitectural remodeling, migration, and proliferation necessary early in the canine corneal healing response, and suppressed expression may contribute to the pathophysiology of nonhealing defects. [ABSTRACT FROM AUTHOR]

Background The aim of the study was to evaluate ex vivo the effects of using a custom tip to direct a pulsed stream of fluid to remove residual lens epithelial cells ( LECs) and reduce posterior capsule opacification ( PCO) formation following phacoemulsification. Methods Twenty-four canine cadaver eyes were assigned to one of three treatment groups. Six eyes (Control Group) had standard phacoemulsification only, nine eyes (Group 1) had standard phacoemulsification followed by capsular washing using intermediate settings (power = 40%, pulses per second [ PPS] = 50, 30 s washing per capsule hemisphere), and nine eyes (Group 2) had standard phacoemulsification followed by aggressive capsular washing (power = 60%, PPS = 50, 60 s washing per capsule hemisphere). Results Control lens capsules had diffuse LECs remaining following standard phacoemulsification and complete ex vivo PCO formation (confluent LECs on the posterior capsule) within 4 ± 2 days (range 2-8 days). Group 1 lens capsules had focal, equatorial LEC clusters remaining following treatment, and complete PCO formation within 9 ± 2 days (range 5-11 days). Group 2 lens capsules had little to no LECs observed following treatment; 5 of 9 capsules had complete PCO formation within 13 ± 2 days (range 9-14 days), and 4 of 9 capsules had no PCO formation by 24 days post-treatment. Conclusions Pulsed fluid lens capsule washing is capable of removing LECs and delaying PCO formation in canine eyes following phacoemulsification ex vivo. Use of more aggressive capsular washing settings resulted in more effective LEC removal and subsequent delay of ex vivo PCO. [ABSTRACT FROM AUTHOR]

Purpose: To confirm that lens epithelial cells (LEC) synthesize 17β-estradiol, active estrogen, and to identify the pathway(s) by which normal and cataractous LEC synthesize 17β-estradiol. Methods: ELISA was used to measure estradiol in aqueous humor; immunohistochemical staining was used to localize estradiol, testosterone and sulfatase; tritiated water release assay was used to measure aromatase activity; and qRT-PCR was used to quantify expression of aromatase and sulfatase in normal and cataractous canine and human LEC. Results: Canine eyes with and without cataracts had no differences in aqueous humor estradiol levels; however, cataractous LEC had more intense immunoreactivity for estradiol than normal LEC. There were little to no differences in canine sulfatase protein and mRNA expression when normal and cataractous LEC were compared. qRT-PCR demonstrated that canine cataractous LEC had significantly higher expression of aromatase; this was confirmed with the tritiated water release assay. Similar to dogs, human cataracts had both sulfatase and aromatase mRNA expression. Conclusions: Normal and cataractous LEC can synthesize estradiol by the sulfatase pathway; however, cataractous LEC appear to use the aromatase pathway as well. Because no differences in aqueous humor estradiol levels were detected, we suspect that estradiol synthesized by the sulfatase pathway is secreted into the aqueous humor; whereas, estradiol synthesized by the aromatase pathway is used for, as yet unknown, intracrine purposes. [ABSTRACT FROM AUTHOR]

Purpose To evaluate the in vitro effects of an aloe vera solution on (i) the viability and wound healing response of corneal cells and (ii) the ability to alter collagenase and gelatinase activities. Methods Primary cultures of corneal epithelial cells and fibroblasts were prepared from grossly normal enucleated canine globes and treated with an aloe solution (doses ranging from 0.0-2 mg/mL). Cellular viability was evaluated using a colorimetric assay. A corneal wound healing model was used to quantify cellular ingrowth across a defect made on the confluent surface. Anticollagenase and antigelatinase activities were evaluated by incubating a bacterial collagenase/gelatinase with aloe solution (doses ranging from 0.0-500 μg/mL) and comparing outcome measures to a general metalloproteinase inhibitor, 1, 10-phenanthroline, and canine serum (doses ranging from 0.0-100%). Results None of the concentrations of aloe solution tested significantly affected the viability of corneal epithelial cells or fibroblasts. Concentrations ≤175 μg/mL slightly accelerated corneal epithelial cell wound closure; this change was not significant. Concentrations ≥175 μg/mL significantly ( P ≤ 0.001) slowed the rate of corneal fibroblast wound closure, while aloe concentrations <175 μg/mL did not significantly alter fibroblast wound closure. Aloe solution did not alter the ability for collagenase to degrade gelatin or collagen Type I but increased the ability for collagenase to degrade Type IV collagen. Conclusions Although additional experiments are required, lower concentrations of aloe solution may be beneficial in healing of superficial corneal wounds to help decrease fibrosis and speed epithelialization. An increase in collagenase activity with aloe vera warrants further testing before considering in vivo studies. [ABSTRACT FROM AUTHOR]

Purpose To characterize and describe the histopathologic findings in equine globes enucleated due to glaucoma. Methods Medical records at The Ohio State University from 1999 to 2012 were reviewed retrospectively. Signalment, history, and treatment data were collected, and histologic slides of enucleated globes were examined and lesions recorded. Twenty-three eyes from 23 horses were eligible for inclusion in this study. Results The majority of affected horses were > 15 years of age (65%). The ages ranged from 5 to 35 years (mean = 17.4 years). The left eye was affected in 10 cases (43%) and the right eye in 13 cases (57%). There were 13 mares (56%) and 10 geldings (44%). Quarter Horses (30%), Appaloosas (26%), and Thoroughbreds (22%) were the most common breeds in the study population. The most common histopathologic changes included hypercellularity of the optic nerve (93%), retinal atrophy (89%), corneal vascularization (83%), descemetization of pectinate ligaments (83%), hypercellularity of the anterior corneal stroma (75%), posterior bowing of the iris base (74%), ciliary body atrophy (74%), corneal striae (70%), pars plana elongation (60%), cataract (53%), and collapsed ciliary cleft/trabecular meshwork (52%). Evidence of uveitis (cataract, lymphoplasmacytic infiltration of the uvea, and/or anterior or posterior synechiae) was present in 20/23 eyes (87%). Conclusions Equine glaucoma most commonly occurs secondary to uveitis with Appaloosas and older horses predisposed. Histologic changes are comparable to prior reports of chronic glaucoma; notable findings not previously described in the horse were posterior bowing of the iris base and relative sparing of the superior retina from atrophy associated with elevated IOP. [ABSTRACT FROM AUTHOR]