Kayoung Yi

Oral alcohol administration disturbs tear film and ocular surface.

PURPOSEnTo investigate whether ethanol administration disturbs the tear film and ocular surface.nnnDESIGNnCase-control study.nnnPARTICIPANTSnTwenty healthy male subjects were recruited. Ethanol was administered to 10 subjects and another 10 subjects served as controls.nnnMETHODSnTwenty healthy male subjects with no ocular disease were recruited. Ethanol (0.75 g/kg) was administered orally at 8 pm for 2 hours to 10 subjects.nnnMAIN OUTCOME MEASURESnThe tear film and ocular surface were evaluated at 6 pm before drinking, at midnight, and immediately (6 am) and 2 hours (8 am) after waking the next morning. Tear osmolarity, ethanol concentration in tears and serum, Schirmers test results, tear film break-up time (TBUT), corneal punctuate erosion, and corneal sensitivity were measured.nnnRESULTSnEthanol was detected in tears and serum at midnight, but it was not detected the next morning. The mean tear osmolarity level increased in the alcohol group at midnight compared with that in the control group (P<0.001). The alcohol group showed a significantly shorter TBUT compared with the control group after drinking alcohol (P<0.001 at 12 am, P<0.001 at 6 am, and P = 0.002 at 8 am). There were significantly higher fluorescein staining scores in the alcohol group compared with those in the control group at 6 am and 8 am (P = 0.001 and P<0.001, respectively). No significant change was shown in corneal sensitivity or Schirmers test results in either group.nnnCONCLUSIONSnOrally administered ethanol was secreted into the tears. Ethanol in tears induced tear hyperosmolarity and shortened TBUT and triggered the development of ocular surface diseases. Similar changes could exacerbate signs and symptoms in patients with ocular surface disease.

Chemical injury-induced corneal opacity and neovascularization reduced by rapamycin via TGF-β1/ERK pathways regulation.

PURPOSEnTo investigate the protective effect of rapamycin against alkali burn-induced corneal damage in mice.nnnMETHODSnBALB/c mice were treated with 0.1 N NaOH to the cornea for 30 seconds. Corneal neovascularization and opacity were clinically evaluated at 1, 2, and 4 weeks after chemical burn injury. Rapamycin was delivered topically to right eyes (1 mg/mL) and injected intraperitoneally (0.2 mg/kg) once a day. Concentrations of interleukin-6 (IL-6) and transforming growth factor-beta1 (TGF-β1) in the cornea were measured by enzyme-linked immunosorbent assay (ELISA). In vitro-cultured human corneal stromal cells were treated with 0 to 500 nM rapamycin for 3 days and then assessed by immunofluorescence staining of vimentin and alpha-smooth muscle actin (α-SMA). Western blotting assays for α-SMA, phosphorylated extracellular signal-regulated kinase (ρ-ERK 1/2), and total ERK 1/2 were also performed.nnnRESULTSnCorneal neovascularization and corneal opacity scores measured 4 weeks after the chemical burn corneal injury were lower in the rapamycin group than in the control group. Two weeks after the chemical burn injury, a significant elevation in the corneal IL-6 levels of the positive control group was observed, compared to the levels in the negative control group or the rapamycin group (P < 0.05). Corneal TGF-β1 levels were lower in the rapamycin-treated group than in the control group at 4 weeks after chemical burn injury (P < 0.05). Moreover, rapamycin inhibited TGF-β1-induced α-SMA expression and augmented ERK 1/2 phosphorylation.nnnCONCLUSIONSnRapamycin treatment reduced corneal opacity and corneal neovascularization in BALB/c mice. Rapamycin protected the cornea from chemical damage via reduction of IL-6 and TGF-β1 expression. Rapamycin reduced α-SMA expression through the ERK 1/2 pathway.

The effects of different culture media on human corneal endothelial cells.

PURPOSEnTo investigate the most appropriate media condition for the proliferation and functional maintenance of human corneal endothelial cells (HCECs).nnnMETHODSnWe cultured HCECs in traditional media (medium A or D) and in stem cell media (medium E or N). The morphology of the cells was evaluated by inverted microscopy. Collagen, type VIII, alpha 2 and sodium-potassium adenosine triphosphatase (Na(+)-K(+) ATPase) expression were analyzed as differentiation markers. Octamer-binding transcription factor 3/4, glial fibrillary acidic protein, nestin and β-catenin expression were evaluated as stem cell associated proteins. The cell proliferation rate was evaluated with a cell counting kit-8 assay. Wound healing assays were also performed. The transendothelial electrical potential difference (TEPD) value was used to estimate the endothelial cell permeability in vitro.nnnRESULTSnThe proliferation and morphology analyses demonstrated that there were significant differences between the media. The expression of differentiation markers and stem cell-associated proteins was different between the media. Medium D resulted in higher proliferation rates compared with the other media, while still maintaining the differentiation potential and surface marker expression profile characteristic of HCECs. Compared with other media, TEPD was higher in medium N.nnnCONCLUSIONSnCulture medium D was superior to the other media with regard to the expression of stem cell-associated proteins, proliferation, and cell migration. However, medium N was more appropriate than the other three media with regard to maintaining the proper cell shape and function.

Does intravitreal injections of bevacizumab for age-related macular degeneration affect long-term intraocular pressure?

Purpose:To evaluate the long-term intraocular pressure (IOP) changes after intravitreal injection of bevacizumab for age-related macular degeneration. Patients and Methods:A total of 83 eyes that received intravitreal injections of bevacizumab for age-related macular degeneration were enrolled. IOP measurements at baseline, 6, 12, 18, and 24 months, and at the last follow-up after injection were analyzed. On the basis of the median number of injections, the changes in IOP were compared. Results:The mean number of injections was 3.71±1.62. There was no significantly higher elevation than baseline IOP (14.11±2.76 mm Hg) after multiple intravitreal injections of bevacizumab (P>0.05). In the group which had ≥4 injections, mean IOP measurements were not higher compared with the group which had <4 injections during the follow-up period (P>0.05). In the patients with preexisting glaucoma (3 eyes), there were no significant increases of IOP during the follow-up period. Conclusions:IOP elevation was not observed during the long-term follow-up period. In addition, the numbers of injection and preexisting glaucoma did not affect IOP changes.

Chemically injured keratocytes induce cytokine release by human peripheral mononuclear cells

PURPOSEnTo establish an in vitro model to study the role of keratocytes in corneal chemical burns and to investigate the interaction between chemically injured keratocytes and human peripheral blood mononuclear cells (PBMCs).nnnMETHODSnHuman keratocytes, epithelial cells, and PBMCs were cultured. The PBMC stimulation assay was then performed using cultured human keratocytes, epithelial cells, and NaOH-treated keratocytes. Matrix metalloprotease-9 (MMP-9), transforming growth factor-beta 1 (TGF-β1), and macrophage migration inhibitory factor (MIF) secretion profiles of activated PBMCs stimulated by NaOH-treated keratocytes were determined by ELISA.nnnRESULTSnHuman keratocytes stimulated PBMC proliferation (p=0.016), and keratocytes treated with various concentrations of NaOH further stimulated PBMC proliferation compared to control cells in a dose-dependent manner (p=0.028 and 0.009). MMP-9 and MIF levels were higher than in the negative controls, while TGF-β1 levels did not differ from those of the negative controls.nnnCONCLUSIONnOur results suggest that PBMCs are stimulated by chemically injured keratocytes, and produce inflammatory cytokines in response. This may be a major mechanism underlying the process causing corneal chemical burn injuries. This model can be used as an in vitro model for further studies on corneal chemical burns.

Stemness characteristics of human corneal endothelial cells cultured in various media.

Purpose: To investigate stemness characteristics of human corneal endothelial cells (HCECs) cultured in various media. Methods: Human corneal endothelial cells were isolated using a sphere-forming assay. Cells were allowed to attach to the bottom of culture plates and were cultured in different media designated as medium A (Opti-MEM I with 8% fetal bovine serum), medium B (DMEM/F12 with B27 supplement), medium E (DMEM/F12 with epidermal growth factor [EGF]), and medium BE (DMEM/F12 with B27 supplement and EGF), respectively. Cell morphology was evaluated with an phase-contrast inverted microscope. Immunofluorescence staining and western blotting of nestin, octamer-binding transcription factor (OCT3/4), glial fibrillary acidic protein (GFAP), zonula occludens-1 (ZO-1), collagen VIII alpha2, and Na+-K+ ATPase was performed. Cell proliferation was assessed with a cell counting kit-8 assay. Results: A few cultured cells stained with nestin. The cells cultured in medium A expressed high levels of GFAP, OCT3/4, and nestin, and higher levels of ZO-1 were expressed in the cells cultured in medium A and medium B compared with cells cultured in the other media. The cells cultured in medium A assumed a fibroblast-like shape, whereas the cells cultured in medium B and medium BE appeared as mosaics. Cell proliferation was highest in medium A compared with those cultured in the other media. Conclusions: Cultured HCECs expressed stem cell markers, including nestin, OCT3/4, and GFAP. The expression of stem cell markers differed according to the culture media and associated proliferation rate.

Utility of the optical quality analysis system for decision-making in cataract surgery

BackgroundA cataract is a common cause of vision impairment that requires surgery in older subjects. The Optical Quality Analysis System (OQAS, Visiometrics SL, Terrassa, Spain) assesses the optical quality of the eye in cataract patients. This study shows the role of the optical quality evaluation system for decision-making in cataract surgery. We investigated the clinical utility of the OQAS for decision-making in cataract surgery.MethodsSixty-seven eyes from 67 patients undergoing cataract surgery and 109 eyes from 109 control subjects were compared. The best corrected visual acuity (BCVA) was measured. The objective scatter index (OSI), modulation transfer function (MTF), Strehl ratio, predicted visual acuity (PVA) 100%, PVA 20%, and PVA 10% were measured using the OQAS. The sensitivity and specificity of the different parameters were analyzed using the receiver operating characteristic (ROC) curve. The main parameters measured were sensitivity and specificity.ResultsThe BCVA, OSI, PVA 100%, PVA 20%, and PVA 10% were higher in the cataract group compared to those in the control group, while the MTF and Strehl ratios were lower (pu2009<u2009xa00.001 for all). ROC analysis showed that the OSI had the largest area under the curve and that the sensitivity and specificity of the OSI were 83.9 and 84.6%, respectively, at the optimal cut-off point of 2.35.ConclusionThe MTF, OSI, Strehl ratio, PVA 100%, PVA 20% and PVA 10% may be useful parameters for preoperative decision-making in cataract surgery. The OSI appears to be the most effective parameter for this purpose.

Are ocular complications of a high-dose glucocorticoid treatment appropriately monitored in patients with rheumatic diseases?

Glucocorticoid is frequently used in treating various rheumatic conditions. However it is known to cause multiple toxicities including cataract or glaucoma. In this study, we examined whether patients with rheumatic diseases had appropriate ocular monitoring for glucocorticoid toxicities. From rheumatology clinics in South New Jersey of the USA, we retrospectively identified patients with ages between 18 and 60 years old who received a high accumulative dose of glucocorticoid, which was defined as glucocorticoid dose greater than prednisone 7.5mg/day × 6 months = 1,350 mg. We observed rheumatologists recommended eye examinations only in 14/37 (37.8 %) of patients. Family history was present for cataract in 13/37 (35.1 %) patients and for glaucoma in 6/37 (16.2 %) patients. Rheumatologists recommended eye examinations in 4/13 (30.7 %) and 0/6 (0 %) patients in each group. This study suggested that rheumatologists did not appropriately monitor ocular complications of a high dose glucocorticoid, even in patients with a positive family history.