Simultaneously Monitoring Whole Corneal Injury with Corneal Optical Density and Thickness in Patients Undergoing Cataract Surgery.

To pursue the least corneal implication during cataract surgery, this study aimed to monitor corneal wound injury after cataract surgery with a novel method. The prospective cohort study involved thirty-two patients, who were assessed by a Scheimpflug tomography AxL® (Oculus GmbH, Wetzlar, Germany) via the following two kinds of indices: whole corneal optical density (COD) and corneal thickness (CT), two weeks before and one month after cataract surgery. The results of the COD revealed that corneal annuli 0.0-2.0 mm and 2.0-6.0 mm, and the average and maximal values at the incisional site significantly increased postoperatively. Also, the anterior and central stroma of 0.0-2.0 mm, and all three depths of 2.0-6.0 mm, increased remarkably after the operation. For the CT, all ranges of diameters plus incisional sites showed significant increases postoperatively. Furthermore, we analyzed the differences (delta) of COD and CT between pre- and post-operation, and found significant correlations between the delta of COD and the delta of CT, regarding annuli 0.0-2.0 mm, 2.0-6.0 mm, and 6.0-10.0 mm, but no correlation at the incisional site, with either average density or maximal density, was detected. We concluded that whole COD and CT, especially at the central zones of the cornea (annulus < 6 mm), are both valuable parameters in the assessment of corneal damage post-cataract surgery, and are independent indices at the incisional site.

Oxidative stress enhanced the transforming growth factor-ß2-induced epithelial-mesenchymal transition through chemokine ligand 1 on ARPE-19 cell.

Fibroblast-like transformation of retinal pigment epithelial (RPE) cells is a pathological feature of proliferative vitreoretinopathy (PVR) that may cause blindness. The effect of oxidative stress alone or together with transforming growth factor-beta 2 (TGF-ß2) on epithelial-mesenchymal transformation (EMT) is not fully understood in RPE. TGF-ß2 induced the upregulation EMT markers including α-smooth muscle actin (α-SMA), Snail, and Slug and downregulation of E-cadherin (E-cad) in ARPE-19 cells. Hydrogen peroxide (H2O2) not only upregulated α-SMA but also enhanced the effect of TGF-ß2 on the expression of Snail and Slug. The CXCL family of cytokines could be the mediators of EMT induced by H2O2 and TGF-ß2. H2O2 induced CXCL1, that upregulated α-SMA and fibronectin. Both SB225002, an inhibitor of CXCR2, and antioxidant N-acetylcysteine suppressed the TGF-ß2-induced EMT in ARPE-19 cells. Taken together, the results suggest that oxidative stress enhanced TGF-ß2-induced EMT through the possible autocrine effect of CXCL1 on CXCR2 in ARPE-19 cells.

Macrophages promote a profibrotic phenotype in orbital fibroblasts through increased hyaluronic acid production and cell contractility.

Graves' orbitopathy (GO) is an autoimmune inflammatory disease affecting the orbit. Orbital fibroblasts are a key component in GO pathogenesis, which includes inflammation, adipogenesis, hyaluronic acid (HA) secretion, and fibrosis. Macrophages are thought to participate in the immunological stage of GO, but whether they can directly affect the fibroblasts phenotype and modulate disease progression is unknown. We previously showed that GO adipogenic and fibrotic phenotypes could be modelled in a pseudo-physiological 3D environment in vitro. Here, we introduced macrophages in this 3D culture model to investigate role for macrophages in modulating adipogenesis, HA production, and contractility in orbital fibroblasts. Macrophages had a minimal effect on lipid droplet formation in fibroblasts, but significantly increased HA production and cell contractility, suggesting that they may promote the fibrotic phenotype. This effect was found to be mediated at least in part through phosphatidylinositol-4,5-bisphosphate 3-kinase (PI3K) activation and linked to an increase in actin polymerization and protrusive activity in fibroblasts. Overall our work shows for the first time a direct role for macrophages in modulating the fibroblasts' phenotype in GO, supporting a role for macrophages in the progression of the fibrotic phenotype through induction of HA production and stimulation of the contractile phenotype in orbital fibroblasts.

Myopia Prevention and Outdoor Light Intensity in a School-Based Cluster Randomized Trial.

PURPOSE: To investigate the effectiveness of a school-based program promoting outdoor activities in Taiwan for myopia prevention and to identify protective light intensities. DESIGN: Multi-area, cluster-randomized intervention controlled trial. PARTICIPANTS: A total 693 grade 1 schoolchildren in 16 schools participated. Two hundred sixty-seven schoolchildren were in the intervention group and 426 were in the control group. METHODS: Initially, 24 schools were randomized into the intervention and control groups, but 5 and 3 schools in the intervention and control groups, respectively, withdrew before enrollment. A school-based Recess Outside Classroom Trial was implemented in the intervention group, in which schoolchildren were encouraged to go outdoors for up to 11 hours weekly. Data collection included eye examinations, cycloplegic refraction, noncontact axial length measurements, light meter recorders, diary logs, and questionnaires. MAIN OUTCOME MEASURES: Change in spherical equivalent and axial length after 1 year and the intensity and duration of outdoor light exposures. RESULTS: The intervention group showed significantly less myopic shift and axial elongation compared with the control group (0.35 diopter [D] vs. 0.47 D; 0.28 vs. 0.33 mm; P = 0.002 and P = 0.003) and a 54% lower risk of rapid myopia progression (odds ratio, 0.46; 95% confidence interval [CI], 0.28-0.77; P = 0.003). The myopic protective effects were significant in both nonmyopic and myopic children compared with controls. Regarding spending outdoor time of at least 11 hours weekly with exposure to 1000 lux or more of light, the intervention group had significantly more participants compared with the control group (49.79% vs. 22.73%; P < 0.001). Schoolchildren with longer outdoor time in school (≥200 minutes) showed significantly less myopic shift (measured by light meters; ≥1000 lux: 0.14 D; 95% CI, 0.02-0.27; P = 0.02; ≥3000 lux: 0.16 D; 95% CI, 0.002-0.32; P = 0.048). CONCLUSIONS: The school-based outdoor promotion program effectively reduced the myopia change in both nonmyopic and myopic children. Outdoor activities with strong sunlight exposure may not be necessary for myopia prevention. Relatively lower outdoor light intensity activity with longer time outdoors, such as in hallways or under trees, also can be considered.

Isolates and antibiotic susceptibilities of endophthalmitis in postcataract surgery: a 12-year review of culture-proven cases.

The purpose of this study was to investigate the spectrum of organisms causing endophthalmitis after cataract surgery in a tertiary medical center in Taiwan and the antibiotic susceptibilities. This was a retrospective case series study. Patients with endophthalmitis after cataract surgery from January 2004 to July 2015 were reviewed. The outcome measures included the identification of isolates, antibiotic susceptibilities, and final visual outcomes. Twenty-one organisms were isolated from 19 cases. The most common organisms were Enterococcus in 38.1 %, especially Enterococcus faecalis, followed by Staphylococcus epidermidis in 28.6 % and Staphylococcus aureus in 9.5 %. All of the Gram-positive isolates tested were susceptible to vancomycin (100 %), and ceftazidime and amikacin were susceptible for Gram-negative organisms. The Gram-positive organisms remain to be the predominant cause of postoperative endophthalmitis, and Enterococcus species has had an increasing incidence. Vancomycin is still the most powerful antibiotic for Gram-positive organisms, while ceftazidime and amikacin are effective for Gram-negative bacteria.

High-fat diet induces toll-like receptor 4-dependent macrophage/microglial cell activation and retinal impairment.

PURPOSE: The toll-like receptor 4 (TLR4) signaling pathway is involved in chronic inflammation and insulin resistance, which are associated with obesity and diabetes mellitus. In the present study, a model of high-fat diet (HFD) feeding of mice was used to investigate the role of TLR4 in overnutrition- and obesity-associated inflammation and infiltration of macrophages and microglia in the retina. METHODS: Wild-type C57BL/6 and TLR4 knockout (TLR4KO; B6.B10ScN-Tlr4(lps-del)/JthJ) mice were fed a HFD or control chow diet (CD) for 6 months. The TLR4 expression, the relative increase in macrophages/microglia (CD11b(+) and CD45(+) cells), the presence of markers of oxidative stress (gp91phox and malondialdehyde; MDA), and DNA damage (phosphorylated histone H2AX; γH2AX) were assessed by real-time PCR and immunofluorescence studies. RESULTS: The HFD for 6 months showed increased obesity, glucose intolerance, and insulin resistance in mice. Toll-like receptor 4 expression was found in vascular pericytes at the inner retina. Increased CD11b(+) and CD45(+) cells, phosphorylated NF-κB, interleukin-6, gp91phox, MDA, and γH2AX were observed in the retina of mice fed a HFD compared to CD counterparts. TLR4KO mice did not show the adverse effects of HFD. CONCLUSIONS: Our results indicate that HFD-induced macrophage/microglial cell activation and retinal impairment were reduced in the absence of TLR4. The findings suggest that TLR4 is implicated in the pathogenesis of retinal diseases caused by metabolic disorders.

Posterior choroidal leiomyoma: a rare case report and literature review.

We report a literature review and detailed evaluation of a rare case of posterior choroidal leiomyoma to emphasize the importance of differentiating this from other choroidal tumors. A 30-year-old male presented with variable blurred vision in his right eye secondary to a choroidal tumor. Clinical examinations were performed including fundus photography, optical coherence tomography, B scans, fluorescein and indocyanine green angiography, computed tomography, and magnetic resonance imaging. Preoperative examination revealed a suspected choroidal melanoma and enucleation was performed. However, a definitive diagnosis of choroidal leiomyoma was made following postoperative pathological light microscopy and immunohistochemical studies. Published case reports were collected and the common characteristics and distinctive features were compared with the current case. Posterior choroidal leiomyoma was summarized from the literature, and beneficial information for diagnosis and treatment was obtained. In conclusion, posterior choroidal leiomyoma is rare and should be differentiated from amelanotic melanomas. Despite the benign nature, an explanation regarding the rare incidence and difficult diagnosis of posterior choroidal leiomyoma must be provided to patients, prior to enucleation or detrimental treatment.

Amyloid-beta mediates the receptor of advanced glycation end product-induced pro-inflammatory response via toll-like receptor 4 signaling pathway in retinal ganglion cell line RGC-5.

Patients with diabetes mellitus have an increased risk of developing Alzheimer's disease. Amyloid-ß, a product of amyloid precursor protein, is associated with neuro-inflammation in patients with Alzheimer's diseases. The correlation between amyloid-beta and advanced glycation end products, which accumulate in tissue of diabetic patients, is not clear. The aims of this study were to determine the effect of advanced glycation end product on the expression of amyloid precursor protein/amyloid-beta and associated pro-inflammatory responses in retinal ganglion cell line RGC-5. Treatment with advanced glycation end product produced upregulation of amyloid precursor protein and increased secretion of amyloid-ß(1-40). Additionally, amyloid-ß(1-40) induced toll-like receptor 4-dependent phosphorylation of tyrosine in myeloid differentiation primary response gene (88). We found that N-[N-(3,5-Difluorophenacetyl)-l-alanyl]-S-phenylglycine t-butyl ester, a γ-secretase inhibitor, reduced the secretion of amyloid-ß(1-40) and inhibited the advanced glycation end product-induced activation of myeloid differentiation primary response gene (88). Amyloid-ß(1-40) induced the activation of NF-κB and the expression of TNFα mRNA. Knockdown of toll-like receptor 4 inhibited the amyloid-ß(1-40)-induced phosphorylation of p65 in NF-κB. Additionally, the nuclear translocation of p65 and transcriptions of TNFα were inhibited by siRNA knockdown of receptor of advanced glycation end product or toll-like receptor 4. The advanced glycation end product-induced secretion of VEGF-A was also reduced by knockdown of toll-like receptor 4. Taken together, our data suggested that amyloid-ß(1-40) mediates the interaction between receptor of advanced glycation end product and toll-like receptor 4. Inhibition of the toll-like receptor 4 is an effective method for suppressing the amyloid-ß(1-40)-induced pro-inflammatory responses in RGC-5 cells.

Involvement of STIM1 and Orai1 in EGF-mediated cell growth in retinal pigment epithelial cells.

BACKGROUND: In non-excitable cells, one major route for calcium entry is through store-operated calcium (SOC) channels in the plasma membrane. These channels are activated by the emptying of intracellular Ca²âº store. STIM1 and Orai1 are major regulators of SOC channels. In this study, we explored the functions of STIM1 and Orai1 in epidermal growth factor (EGF)-induced cell proliferation and migration in retinal pigment epithelial cells (ARPE-19 cell line). RESULTS: EGF triggers cell proliferation and migration in ARPE-19 cells. Cell proliferation and migration involve STIM1 and Orai1, as well as phosphorylation of extracellular signal-regulated protein kinase (ERK) 1/2, and Akt. Pharmacological inhibitors of SOC channels and siRNA of Orai1 and STIM1 suppress cell proliferation and migration. Pre-treatment of mitogen-activated protein kinase kinase (MEK) inhibitors and a phosphatidylinositol 3 kinases (PI3K) inhibitor attenuated cell proliferation and migration. However, inhibition of the SOC channels failed to prevent EGF-mediated ERK 1/2 and Akt phosphorylation. CONCLUSIONS: Our results showed that STIM1, Orai1, ERK 1/2, and Akt are key determinants of EGF-mediated cell growth in ARPE-19 cells. EGF is a potent growth molecule that has been linked to the development of PVR, and therefore, STIM1, Orai1, as well as the MEK/ERK 1/2 and PI3K/Akt pathways, might be potential therapeutic targets for drugs aimed at treating such disorders.

High-mobility group box 1 protein is implicated in advanced glycation end products-induced vascular endothelial growth factor A production in the rat retinal ganglion cell line RGC-5.

PURPOSE: High-mobility group box 1 protein (HMGB1) has been reported to be a potent proangiogenic factor induced by inflammatory stress. In this study, we explore the role of HMGB1 in advanced glycation end products (AGEs)-induced vascular endothelial growth factor A (VEGF-A) production in rat retinal ganglion cell line 5 (RGC-5) cells. METHODS: The VEGF-A protein and mRNA levels in conditioned medium of RGC-5 cells incubated with AGE-modified BSA (AGE-BSA) were examined with real-time PCR and enzyme-linked immunosorbent assay (ELISA), and BSA-treated cells were used as controls. The expression of HMGB1, c-Jun N-terminal kinase (JNK), extracellular-signal-regulated kinase (ERK), and p38 mitogen-activated protein kinase (p38 MAPK) was assessed with immunofluorescence and western blot analysis. Reactive oxidative species (ROS) were detected with flow cytometry measurements of peroxide-dependent oxidation of 2'-7'-dichlorofluorescein-diacetate (DCFH-DA). N-Acetyl-L-cysteine (NAC), glycyrrhizin (GZ), and SP600125 were used to block ROS, HMGB1, and JNK, respectively. RESULTS: Compared with the BSA controls, the RGC-5 cells incubated with AGE-BSA showed a dose- and time-dependent increase in VEGF-A mRNA and VEGF-A protein secretion in the supernatant, with the highest levels achieved at 24 h. AGE-BSA stimulated a significant release of HMGB1 in the supernatant and a significant increase of intracellular ROS production at 3 h. NAC blocked HMGB1 production in a dose-dependent manner. Blocking with GZ, NAC, and JNK significantly suppressed AGE-induced VEGF-A production. CONCLUSIONS: HMGB1 is implicated in the production of VEGF-A in retinal ganglion cell line-5 (RGC-5). Blocking HMGB1, ROS, or the JNK pathway may attenuate VEGF-A production, suggesting HMGB1 and related signaling molecules play a role in diabetic retinopathy.

Isodesacetyluvaricin, an Annonaceous acetogenin, specifically inhibits gene expression of cyclooxygenase-2.

Cyclooxygenase-2 (COX-2) is an inducible isoform of the enzyme responsible for the synthesis of several inflammatory mediators. In a search for phytochemicals with anti-inflammatory activity, the COX-2 inhibitory activity of 15 typical Annonaceous acetogenins was examined. Isodesacetyluvaricin (1), from the Formosan tropical fruit tree Annona glabra, exhibited the most potent activity. Reverse transcription PCR was used to test the effect of 1 on epidermal growth factor-stimulated expression of COX-2 in cultures of A431 human epidermoid carcinoma cells. Three hours after exposure to 1 (5 µM), A431 cells had barely detectable levels of COX-2 mRNA. A corresponding but smaller decline in the COX-2 protein appeared on using Western blots. Lipopolysaccharide-stimulated expression of COX-2 in Raw 264.7 mouse leukemic monocyte-macrophages showed a similar decrease. Luciferase assays revealed that cells exposed to 1 had reduced activities of two COX-2 promoter-transcription factors: cAMP response element-binding factor and nuclear factor of activated T-cells. Compound 1 did not affect cell proliferation, as measured by a colorimetric assay, or intracellular store-operated calcium influx, as determined by fluorescence imaging. Thus, 1 may serve as a lead compound for targeting inflammatory diseases as well as angiogenesis and cancer metastasis.

Review of 20 years' clinical experience with retinoblastomas in southern Taiwan.

BACKGROUND: Retinoblastomas are the most common malignant intraocular tumor of childhood. We describe the survival outcomes and prognostic factors of patients with a retinoblastoma receiving primary treatment at our hospital over the last 20 years. METHODS: A retrospective series study of 30 retinoblastoma cases treated from January 1, 1987 to August 31, 2006 was conducted from a review of medical records and histopathological sections. Variables, including age at onset, laterality, treatment modalities, treatment delay, and optic nerve invasion, were analyzed to elucidate the prognostic factors associated with cumulative survival. RESULTS: Most of the cases had an advanced retinoblastoma, and 23 patients received enucleation treatment. The average period of delay for treatment was 5.37 months after discovery of the disease. The overall cumulative survival rate was 83.08%. Patients with optic nerve invasion had a significantly lower survival rate (60.0%) than those without optic nerve involvement (94.75%). Treatment delay in excess of 6 months was correlated with tumor invasion of the optic nerve. CONCLUSIONS: Tumor invasion of the optic nerve is the most significant prognostic factor for surviving a retinoblastoma. Delayed treatment increases the risk of optic nerve invasion. Parental awareness of both the risk of this consequence and the significance of early treatment is vital to achieving improved survival rates.