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Purpose: Unstable tear film characterized by shorting of tear break-up time (BUT) is associated with discomfort and dryness in contact lens wearers. The glycocalyx is thought to be crucial in maintaining the wettability and lubrication of the ocular surface. We evaluated the ocular surface glycocalyx in soft contact lens (SCL) wearers using a fluorescein-labeled wheat germ agglutinin (F-WGA) as a marker to demonstrate the ocular surface glycoconjugatesin vivo. Methods: Twenty experienced SCL wearers and 20 healthy volunteers with no history of CL wearing (controls) were enrolled in the study. After applying a 5% F-WGA solution to the eyes of study individuals, fluorescent intensities in their respective central corneas were measured by fluorophotometry. The relationship between F-WGA intensity in the corneal surface and clinical parameters associated with contact lens wear were analyzed. Results: F-WGA fluorescence intensity in the SCL group was 418.5 ± 103.3, which was significantly lower than that of the controls (825.0 ± 179.8;p < 0.0001, Mann–Whitney test). F-WGA fluorescence intensity was not correlated with Schirmer’s test values or age, whereas a statistically significant correlation between F-WGA fluorescence intensity and tear film BUT was observed (r = 0.77,p < 0.0001). The decrease in F-WGA fluorescence intensity could be reversed by discontinuation of SCL use. Conclusion: Reduction and/or compositional alteration of ocular surface glycocalyx may be one of the causative factors of SCL-induced eye dryness. [ABSTRACT FROM PUBLISHER]

Purpose: This study was undertaken to determine the effect of topical application of diquafosol tetrasodium on proteins and mucin-like substances from tears of clinically healthy subjects. Methods: Tears were collected from both the eyes of 10 healthy volunteers. Diquafosol tetrasodium solution (3%) was applied once to the right eye and 0.9% sodium chloride solution (saline) once to the left eye. Tear samples were collected by Schirmer test strips before application and 5, 15, 30 and 60 min after application. Sialic acid, a marker of mucin-like substances, and major tear proteins including secretory IgA, lactoferrin, lipocalin-1, and lysozyme were measured by high performance liquid chromatography. Results: Levels of total protein, sIgA and lysozyme were transiently decreased in both groups but returned to baseline levels within 15 min after application. The concentration of lactoferrin and lipocalin-1 did not change significantly in both groups. Sialic acid in tears was significantly decreased 5 min after saline application, but significantly increased 5 min after diquafosol application. No significant difference in sialic acid was seen after 15 min in both groups. Conclusions: Topical application of saline and diquafosol resulted in transient decrease of tear proteins possibly due to wash out or dilution effects. In contrast, diquafosol application significantly increased sialic acid, although the effect was transient. This suggests diquafosol stimulates the secretion of mucins from ocular tissues of healthy human subjects. [ABSTRACT FROM PUBLISHER]

PURPOSE. To investigate clinical factors relatedto the aqueous humor levels of vascular endothelial growth factor (VEGF) andhepatocyte growth factor (HGF) in patients with proliferative diabetic retinopathy(PDR). METHODS. Undiluted aqueous humor was obtained during ocular surgery from46 eyes of 46 patients and the levels of growth factors were measured usingenzyme-linked immunosorbent assays. VEGF and HGF levels were compared withthe number of photocoagulation. VEGF and HGF levels in patient groups stratifiedaccording to the existence of vitreous hemorrhage, retinal detachment, andfibrovascular membrane were analyzed. And clinical parameters associated withthe growth factors were determined by multiple regression analysis. RESULTS. The levels of VEGF decreased significantly as the extent of photocoagulationincreased and showed significant positive correlation with the existence ofvitreous hemorrhage. There was no significant correlation between VEGF levelsand the existence of fibrovascular membrane and traction retinal detachment. The levels of HGF also decreased significantly as the extent of photocoagulationincreased, but increased significantly when fibrovascular membrane existed.There were no significant correlations between HGF levels and the existenceof vitreous hemorrhage and traction retinal detachment. Concerning systemic conditions, each growth factor has no significant correlationwith duration and type of diabetes mellitus, the treatment regimen, the controlof hemoglobin A1C, and the existences of hypertension or renal dysfunction. CONCLUSION. The therapeutic effect of panretinal photocoagulation on PDRmight be partly exerted by reduction of the levels of VEGF and HGF in ocularfluid. Since the clinical parameters associated with VEGF were different fromthose associated with HGF, these growth factors might influence the progressionof retinopathy in different ways. [ABSTRACT FROM AUTHOR]

PURPOSE. To investigate corneal deposits associatedwith kerato-epithelin (KE) in three corneal dystrophies harboring mutationsat Arg-124 in the BIGH3 gene. METHODS. Six patients with Avellino corneal dystrophy (ACD) associatedwith R124H, one patient with superficial granular corneal dystrophy (SGCD)associated with R124L, and seven patients with lattice corneal dystrophy type1 (CDL1) associated with R124C were examined. Corneal buttons obtained duringkeratoplasties were stained with Masson's trichrome and with Congo red, andimmunostained with antibodies specific for N-terminal and C-terminal portionsof KE (KE-15 and KE-2, respectively). RESULTS. In all corneas with ACD, subepithelial to midstromal depositsof granular material stained with KE-2 and KE-15. However, deep stromal depositscontaining amyloid reacted with KE-2, but not KE-15. Granular deposits inthe subepithelial layer observed in SGCD stained intensely with KE-2 and KE-15.In all corneas with CDL1, subepithelial and midstromal amyloid deposits stainedwith KE-2; these deposits did not stain with KE-15. Deposits between the epitheliallayer and Bowman's layer stained with Masson's trichrome but not with Congored in five of the seven corneas; these deposits were stained with both KE-2and KE-15. CONCLUSIONS. Deposits in corneal buttons involved by ACD, SGCD, and CDL1included forms of the BIGH3 gene product, KE. An N-terminal sequenceof KE may be related to formation of amyloid associated with R124 mutations. [ABSTRACT FROM AUTHOR]

PURPOSE. Eicosanoids that are present in inflamedtissues are thought to play a significant role in angiogenesis. Cyclooxygenase,a key enzyme in eicosanoid synthesis, has recently been shown to exist intwo isoforms: the constitutive COX-1 and the inducible COX-2. This study wasundertaken to determine the role of COX-2 in the corneal angiogenic response. METHODS. Angiogenesis in the rat cornea was provoked by chemical cautery.Either NS-398, a selective COX-2 inhibitor, or indomethacin, a non-selectiveCOX inhibitor, was applied topically 3 times daily for 4 days. Neovascularizationwas quantitated by digital image analysis in corneal flat preparations. Totest their inhibitory effects on eicosanoid synthesis, normal or cauterizedcorneas were incubated in the culture medium with the inhibitor. ProstaglandinE2 in the medium was assayed using an enzyme-linked immunosorbent assay. RESULTS. Both NS-398 and indomethacin significantly inhibited corneal neovascularizationwith the % inhibition of 36.4 ± 9.6%, and 38.5 ± 9.0%, respectively,when applied topically at a concentration of 0.1% (p < .001). Neither reducedthe angiogenic response at a concentration of 0.01% or below. PGE[sub 2] production in the cauterized cornea was 2.0 times higher than that in thecontrols. In normal corneas, indomethacin inhibited PGE[sub 2] synthesisby 80%, whereas NS-398 inhibited it by no more than 20%. In contrast, in injuredcorneas, both indomethacin and NS-398 inhibited PGE[sub 2] synthesisin a similar fashion, with a maximal inhibition rate of 75 to 80%. CONCLUSIONS. Our results suggest that COX-2 induction in cauterized corneasincreases the level of eicosanoids, which result in corneal angiogenesis. [ABSTRACT FROM AUTHOR]