Modification of a Selective NTRK2 Agonist and Confirmation of Activity in a Glaucoma-on-a-Chip Model.

Purpose: RNYK is a selective agonist of the neurotrophic tyrosine kinase receptor type 2 (NTRK2) which has been screened from a phage-displayed peptide library. Its sequence is SGVYKVAYDWQH, similar to a native NTRK2 ligand, that is, brain-derived neurotrophic factor (BDNF). The current study was performed to recognize and confirm critical residues for RNYK activity in a glaucoma-on-a-chip model. Methods: We designed a modified RNYK (mRNYK) peptide based on hotspots of the RNYK sequence identified by alanine scanning. The critical residues consisted of tyrosine, valine, aspartic acid, and tryptophan (YVDW); however, lysine and glutamine were also maintained in the final sequence (YKVDWQ) for forming amide bonds and peptide dimerization. The affinity of mRNYK binding was confirmed by testing against NTRK2 receptors on the surface of ATRA-treated SH-SY5Y cells. The neuroprotective effect of mRNYK was also evaluated in cell culture after elevated pressure insult in a glaucoma-on-a-chip model. Results: The primary amine on the lysine side-chain from one sequence (YKVDWQ) reacted with a γ-carboxamide group of glutamine from the other sequence, forming dimeric mRNYK. In silico, molecular dynamic simulations of the mRNYK-NTRK2 complex showed more stable and stronger interactions as compared to the RNYK-NTRK2 complex. In vitro, mRNYK demonstrated a neuroprotective effect on SH-SY5Y cells under normal and elevated pressure comparable to RNYK. The 50% effective concentration (logEC50) for mRNYK was 0.7009, which was better than RNYK with a logEC50 of 0.8318. Conclusion: The modified peptide studied herein showed improved stability over the original peptide (RNYK) and demonstrated potential for use as a BDNF agonist with neuroprotective properties for treatment of neurodegenerative disorders such as glaucoma.

Polymeric Propranolol Nanoparticles for Intraocular Delivery: Formulation, Characterization, and Vitreous Pharmacokinetics.

Purpose: Recent studies have reported the promising effect of intravitreal propranolol on retinal neovascularization. However, rapid clearance and short half-life of the drug in the vitreous are the main drawbacks of this therapeutic approach. This study investigates the extension of the residence time of propranolol in the vitreous by polymeric nanoparticles (NPs) with the prospect of improving choroidal neovascularization treatment. Methods: The poly (lactic-co-glycolic) acid (PLGA) NPs were fabricated by a modified double emulsion solvent evaporation method and the obtained NPs were characterized for their size, poly dispersity index (PDI), and surface image. The in vitro release, cell cytotoxicity, and uptake of NPs were also evaluated. To investigate the effect of the vitreous pharmacokinetic drug loaded NPs versus that of the free propranolol, they were intravitreally injected into the rabbits' eyes and the drug vitreous concentrations in defined intervals were analyzed by high performance liquid chromatography (HPLC). Results: The spherical NPs with about 230 nm size, and almost 10% drug loading were obtained. Based on the 3-(4, 5-Dimethylthiazol-2-Yl)-2, 5-Diphenyltetrazolium Bromide (MTT) outcomes, 30 µg/ml of propranolol was considered as the guide dosage in the intravitreal injection. Confocal microscopy images verified the presence of labeled NPs in the posterior segment after five days of receiving the injection. In vivo assay revealed that the vanishing rate of propranolol in rabbits treated with propranolol NPs was reduced at twice the rate as compared to that of the vanishing rate experienced with only the free drug. Conclusion: PLGA NPs can prolong the existence of propranolol in both vitreous and posterior ocular tissues, and thus, may provide an effective approach in treatment of posterior segment neovascularization.

A registration trend in eyelid skin cancers and associated risk factors in Iran, 2005-2016.

BACKGROUND: Eyelid skin cancers are the most prevalent ophthalmic malignancies. This study aimed to evaluate the association of the Human Development Index (HDI) and lifestyle risk factors with eyelid skin cancers in Iran. METHODS: This ecological study analyzed the data collected from the Iranian National Population-based Cancer Registry (2005-2016). The data on provincial-level eyelid skin cancer risk factors were obtained from national sources. The association between provincial HDI and lifestyle risk factors with the prevalence of eyelid skin cancers was assessed. RESULTS: The mean 12-year age-standardized incidence rate (ASIR) of eyelid skin cancers was 16.22 per 100,000 (9,104 cases). The overall ASIR showed an upward trend with an estimated annual average increase of 0.006 per year. There were positive correlations between the prevalence of overall eyelid skin cancers and provincial HDI, smoking, and obesity (r = 0.32, 0.42, and 0.37, respectively). In multivariate analysis, obesity/overweight remained a positive predictor for high prevalence of total eyelid skin cancers (OR = 1.97, 95%CI = 1.08-3.58, P = 0.026), carcinoma (2.10, 1.15-3.83, P = 0.015), and basal cell carcinoma (1.48, 0.99-2.20, P = 0.054). CONCLUSIONS: An increasing trend in ASIR of eyelid skin cancers was observed in more than a decade in Iran which was positively associated with provincial HDI and prevalence of obesity. The findings of the study highlight the importance of promotional programs for preventing obesity/overweight and appropriate allocation of screening facilities based on the HDI level.

microRNA-96 targets the INS/AKT/GLUT4 signaling axis: Association with and effect on diabetic retinopathy.

Background: miR-96-5p is a highly expressed microRNA in the retina of subjects with diabetes. The INS/AKT/GLUT4 signaling axis is the main cell signaling pathway of glucose uptake in cells. Here, we investigated the role of miR-96-5p in this signaling pathway. Methods: Expression levels of miR-96-5p and its target genes were measured under high glucose conditions, in the retina of streptozotocin-induced diabetic mice, in the retina of AAV-2-eGFP-miR-96 or GFP intravitreal injected mice and in the retina of human donors with diabetic retinopathy (DR). MTT, wound healing, tube formation, Western blot, TUNEL, angiogenesis assays and hematoxylin-eosin staining of the retinal sections were performed. Results: miR-96-5p expression was increased under high glucose conditions in mouse retinal pigment epithelial (mRPE) cells, in the retina of mice receiving AAV-2 carrying miR-96 and STZ-treated mice. Expression of the miR-96-5p target genes related to the INS/AKT/GLUT4 signaling pathway was reduced following miR-96-5p overexpression. mmu-miR-96-5p expression decreased cell proliferation and thicknesses of retinal layers. Cell migration, tube formation, vascular length, angiogenesis, and TUNEL-positive cells were increased. Conclusions: In in vitro and in vivo studies and in human retinal tissues, miR-96-5p regulated the expression of the PIK3R1, PRKCE, AKT1, AKT2, and AKT3 genes in the INS/AKT axis and some genes involved in GLUT4 trafficking, such as Pak1, Snap23, RAB2a, and Ehd1. Because disruption of the INS/AKT/GLUT4 signaling axis causes advanced glycation end product accumulation and inflammatory responses, the inhibition of miR-96-5p expression could ameliorate DR.

Risk of Induction of Corneal Neovascularization with Topical Erythropoietin: An Animal Safety Study.

Purpose: To evaluate the pro-angiogenic effect of topical erythropoietin on cornea in chemical burn-injured rabbit eyes. Methods: The corneal alkali-burn injury was induced in 10 eyes of 10 rabbits using filter paper saturated with 1.0 mol sodium hydroxide. The eyes were categorized into the treatment group (n = 5) that received topical erythropoietin (3000 IU/mL) every 8 hr for one month versus the control group (n = 5) that received normal saline every 8 hr for one month. All eyes were treated with topical ciprofloxacin every 8 hr until corneal re-epithelialization was complete. Corneal epithelial defects, stromal opacity, and neovascularization were evaluated after the injury. At the conclusion of the study, the rabbits were euthanized and their corneas were submitted to histopathological examination. Results: Baseline characteristics including the rabbits' weight and the severity of corneal injury were comparable in two groups. Time to complete corneal re-epithelialization was 37 days in the treatment group and 45 days in the control group (P = 0.83). There was no significant difference between the groups in the rate of epithelial healing or corneal opacification. Clinical and microscopic corneal neovascularization was observed in one eye (20%) in the treatment group and two eyes (40%) in the control group (P = 0.49). Conclusion: Recombinant human erythropoietin administered topically did not induce vessel formation in rabbit corneas after chemical burn.

Thickness Profile of Donated Corneas Preserved in Optisol-GS versus Sinasol: An Ex-vivo Study.

Purpose: This study aimed to compare the thickness profile and the endothelial cell density (ECD) of donated corneas maintained in Optisol-GS with those preserved in Sinasol over seven days. Methods: Twenty paired donor corneas were received from the Central Eye Bank of Iran. After recording the osmolarity of each medium, one of each of the cornea pairs was preserved in either Optisol-GS or Sinasol media. Then, slit-lamp biomicroscopy and specular microscopic examinations were performed at the baseline and on day seven. Visante optical coherence tomography (V-OCT) was also performed at 1 hour (h), 24h, 72h, and one week post-preservation. The specular microscopic and V-OCT values were then compared between the two groups. Results: The mean osmolarity of the Sinasol group was significantly less than the Optisol-GS group (296 vs. 366 mOsm/L, P = 0.0008). The mean central corneal thickness at the measurement points was comparable between the two groups. However, the increase of thickness one week post-preservation in the Sinasol group was remarkably lower than those in the Optisol-GS group (P = 0.027). The mean ECD was comparable between the groups at the baseline and on day seven. However, the mean change of ECD from baseline to day seven was considerably higher in the Optisol-GS group than in the Sinasol group (P = 0.019). Conclusion: Corneal storage in Sinasol over seven days provides better and superior maintenance and preservation of corneal tissue deturgescence and a lower rate of ECD loss over Optisol-GS.

Augmented Expression of NOGO-A and Its Receptors in Human Retinal Pigment Epithelial Cells Following Treatment with Human Amniotic Fluid.

Background: Nogo-A, a myelin-associated inhibitor for neurite outgrowth, has important role in visual system development. Trans-differentiation ability of human amniotic fluid (HAF) on human retinal pigment epithelial cells (hRPEs) towards neural progenitor cells has been observed in several studies. We aimed to investigate the expression of NOGO-A gene and its receptors as a marker of neural differentiation in HAF-treated hRPE cells. Methods: hRPE cells were cultivated and immune characterized via RPE65 and cytokeratin 8/18 protein markers. Also, the cytotoxicity effect of 30% HAF on hRPE cells was evaluated using ELISA cell death assay. Finally, expression of NOGO-A and its receptors, RTN4R and LINGO1 was evaluated in the cells treated with HAF in comparison with FBS-treated cells using quantitative real-time PCR. Results: Harvested cells showed immunoreactivity for cytokeratin 8/18 and RPE65, confirming the hRPE cell identity. Besides, HAF had no cytotoxic effect on hRPE cells compared with FBS-treated cells. Results showed that NOGO-A and its receptors were expressed in cultured hRPE cells. Besides, comparative gene expression analysis revealed significant increased expression of the investigated genes in HAF-treated hRPE cells compared to FBS-treated cells. Conclusion: Augmented expression of NOGO-A and its receptors can support neural differentiation of hRPE when the cells are treated with HAF. Our outcomes provide more evidences on the trans-differentiation ability of HAF on hRPE cells into neural progenitors and retinal neural cells, but further studies are needed to elucidate the exact mechanism.

Eye Bank Records on Pediatric Keratoplasty.

Purpose: To report eye bank records for pediatric keratoplasty in Iran between 2006 and 2019. Methods: In a retrospective study, all electronic records of the Central Eye Bank of Iran for pediatric keratoplasty between April 2006 and March 2019 were analyzed in terms of indications for keratoplasty, surgical techniques, their corresponding trends, and post-transplantation graft clarity. Results: Our database included 2178 eyes from 2050 pediatric cases. The leading indications for keratoplasty included acquired nontraumatic diseases (75.8%), congenital abnormalities (12.7%), corneal regraft (8.3%), and acquired traumatic diseases (3.2%). Keratoconus was the most common acquired nontraumatic cause (58%) and more common in the age group > 12 years than those ≤ 12 years (P < 0.001). Congenital corneal abnormalities and regrafts were more common in the age group ≤ 12 years (both P < 0.001). The most common surgical technique was penetrating keratoplasty (PKP, 90.9%) followed by deep anterior lamellar keratoplasty (DALK, 7.3%), Descemet stripping automated endothelial keratoplasty (DSAEK, 1.1%), anterior lamellar keratoplasty (0.5%), and keratolimbal allograft transplantation (0.2%). DSAEK was more common in the age group ≤ 12 years (P = 0.002), which, unlike PKP and DALK, showed a significant ascending trend over the 14-year period (P = 0.018). Post-transplantation graft clarity was 96.8%. Conclusion: Keratoconus was the leading indication for pediatric keratoplasty in Iran. Although PKP was the predominant keratoplasty procedure for the treatment of pediatric corneal disorders, it showed a significant descending trend over the 14 years.

Mutation Screening of Six Exons of ABCA4 in Iranian Stargardt Disease Patients.

PURPOSE: Stargardt disease type 1 (STGD1) is a recessively inherited retinal disorder that can cause severe visual impairment. ABCA4 mutations are the usual cause of STGD1. ABCA4 codes a transporter protein exclusively expressed in retinal photoreceptor cells. The genecontains 50 exons. Mutations are most frequent in exons 3, 6, 12, and 13, and exons 10 and 42 each contain two common variations. We aimed to screen these exons for mutations in Iranian STGD1 patients. METHODS: Eighteen STGD1 patients were recruited for genetic analysis. Diagnosis by retina specialists was based on standard criteria, including accumulation of lipofuscin. The six ABCA4 exons were PCR amplified and sequenced by the Sanger method. RESULTS: One or more ABCA4-mutated alleles were identified in 5 of the 18 patients (27.8%). Five different mutations including two splice site (c.1356+1G > A and c.5836-2A > G) and three missense mutations (p.Gly1961Glu, p.Gly1961Arg, and p.Gly550Arg) were found. The p.Gly1961Glu mutation was the only mutation observed in two patients. CONCLUSION: As ABCA4 mutations in exons 6, 12, 10, and 42 were identified in approximately 25% of the patients studied, these may be appropriate exons for screening projects. As in other populations, STDG1 causative ABCA4 mutations are heterogeneous among Iranian patients, and p.Gly1961Glu may be relatively frequent.

Comparative culture of human corneal endothelial cells following treatment with human platelet lysate/fibrin hydrogel versus Y-27632 ROCK inhibitor: in vitro and ex vivo study.

PURPOSE: The advancement of tissue engineering and cell therapy research has resulted in innovative therapeutic options for patients with corneal endothelial diseases. The aim of this study was to compare the potential effect of using human platelet lysate (HPL)/Fibrin hydrogel versus using a Y-27632 ROCK inhibitor, on the culture of human corneal endothelial cells (HCECs) under in vitro and ex vivo conditions. METHODS: HCECs were isolated from human donors and treated separately with HPL/Fibrin hydrogel, a Y-27632 ROCK inhibitor, and fetal bovine serum (FBS). MTT viability assay and cell counting were performed on the treated cells. Subsequently, we prepared ex vivo models of human corneal endothelial dysfunction and incubated them with DiI-labeled-HCECs. Specular and fluorescence microscopy were then performed on each of the ex vivo models. RESULTS: In comparison, similar viability results were achieved in the cells treated with HPL/Fibrin hydrogel versus those treated with the Y-27632 ROCK inhibitor, but both treatments showed higher viability than the control group (FBS). More importantly, based on the specular and fluorescence microscopic results, the HPL/Fibrin hydrogel and the Y-27632 ROCK inhibitor treatments showed similar inducible effects on the attachment of the cells to the Descemet membranes of the ex vivo models. CONCLUSION: HPL/Fibrin hydrogel and Y-27632 ROCK inhibitor have similar inducible effects on the viability and attachment of the HCECs. A definite advantage of treating cells with HPL/Fibrin hydrogel is that it serves as a xeno-free and biocompatible material which can have autologous applications in future usage by clinics.

Potential of a novel scaffold composed of human platelet lysate and fibrin for human corneal endothelial cells.

Cell-based therapies have been emerged to find innovative solutions for corneal endothelial dysfunction. The aim of this study is to investigate the suitability of a blended scaffold containing human platelet lysate (HPL) and fibrin not only for cultivating human corneal endothelial cells (HCECs) but also for serving as a scaffold for the respected cells. We isolated HCECs from human donors and encapsulated the cells with three concentrations of HPL/Fibrin scaffold, namely HPL/Fibrin 1, HPL/Fibrin 2 and HPL/Fibrin 3, by adding 28.9, 57.8 and 86.7 mg/dl of fibrinogen to HPL to obtain a final percentage of 10, 20 and 30 % of fibrinogen, respectively. SEM imaging and swelling test were done to characterize the scaffolds. Cell viability assay and cell counting were performed on the cells. HCECs were characterized by morphology and immunocytochemistry. SEM imaging on freeze-dried scaffolds showed higher porosity of HPL/Fibrin 1 and HPL/Fibrin 2 than HPL/Fibrin 3, but larger pores were observed only in HPL/Fibrin 1. Cellular attachment and morphology on HPL/Fibrin 1 were appropriate by SEM imaging. A higher swelling rate was observed in HPL/Fibrin 1. After 3 and 5 days, higher numbers of cells were observed specifically in HPL/Fibrin 1. A higher expression of Na+/K+-ATPase, ZO-1 and vimentin proteins was detected in the HPL/Fibrin 1-cultured HCECs as compared with control (no scaffold). HPL/Fibrin can be used as a suitable scaffold for HCECs while preserving the cells viability. Further investigations are necessitated to approve the beneficial effects of the suggested scaffold for delivering and transplantation of cultivated HCECs into the anterior chamber of the eye.

Rhino-orbital mucormycosis during steroid therapy in COVID-19 patients: A case report.

PURPOSE: To report two cases of COVID-19 under treatment with a corticosteroid; in one case rhino-orbitocerebral mucormycosis and in another one rhino-orbital mucormycosis developed. CASE PRESENTATION: A 40-year old woman and a 54-year old man with severe COVID-19 underwent corticosteroid therapy for immune-related lung injuries. The first case presented with a bilateral visual loss and complete ophthalmoplegia of the right eye. The second case presented with vision loss, proptosis, orbital inflammation, and complete ophthalmoplegia on the left side. Histopathologic, nasal endoscopic examinations, and radiologic findings confirmed mucormycosis in both patients. The patients denied orbital exenteration and were managed with systemic amphotericin B and daily endoscopic sinus debridement and irrigation with diluted amphotericin B. Because of the intracranial space involvement, the first case died. The second case was successfully managed surgically and medically. CONCLUSION: Rhino-orbital/cerebral mucormycosis may be developed in COVID-19 patients under treatment with corticosteroid, and requires prompt diagnosis and management.

Prenatal diagnosis of primary congenital glaucoma and histopathological features in a fetal globe with cytochrome p4501B1 mutations.

BACKGROUND/OBJECTIVES: This study aims to report the developmental and histopathological features of ocular tissues from an electively aborted human fetus with mutations in cytochrome p4501B1, and thus predisposed to primary congenital glaucoma in comparison to an age-matched healthy fetal globe. SUBJECTS/METHODS: Both eyes of two 17-week gestational aged fetuses, the first with CYP1B1 mutations and the second as healthy control fetus, were studied. Hematoxylin and eosin, Periodic acid-Schiff, Gomori's trichrome, and Verhoeff-Van Gieson staining protocols in addition to immunohistochemistry staining using anti-cytochrome p4501B1, anti-fibrillin-1, and anti-4-hydroxy-2-nonenal antibodies, as primary antibodies, were performed to assess the effect of the mutations on tissue development, cytochrome p4501B1 protein expression, extracellular matrix structure, and oxidative stress in the developing fetus eye. Quantitative analyses were performed using ImageJ software. Student's t-test was used for statistical analysis and P-values <0.05 were considered as significant. RESULTS: Delayed development in ocular tissues, decreased expression of cytochrome p4501B1 protein, irregular extracellular matrix structure, and increased oxidative stress biomarker were evident in the ocular tissues of the fetus with cytochrome p4501B1 mutations as compared to a normal globe from an age-matched fetus. CONCLUSION: To the best of our knowledge, this is the first report of prenatal diagnosis of primary congenital glaucoma. We also describe histopathological changes in the primary congenital glaucoma-affected globes revealing the effect of cytochrome p4501B1 deficiency on ocular tissues during early fetal development contributing to the glaucoma phenotype.

Sinasol versus Optisol-GS for cold preservation of human cornea: a prospective ex vivo and clinical study.

To compare ex vivo results of donor corneas maintained in Sinasol with those stored in Optisol-GS and reporting clinical outcomes of grafted Sinasol-versus Optisol-GS-stored corneas. In phase I, paired donor corneas were maintained in Sinasol or Optisol-GS. Afterward, the corneas were subjected to slit-lamp biomicroscopic and specular microscopic examinations on days 1 and 7, and then to trypan blue staining on day 7. The same examinations were performed on the corneas that were kept in Sinasol or Optisol-GS for 14 days. In phase II, the post-operative reports of 72 consecutive corneal transplantations were recorded using Sinasol- or Optisol-GS-preserved corneas. In phase I, 128 corneas from 64 donors and 59 corneas from 33 donors were investigated for 7 and 14 days, respectively. The EC indices were comparable between the groups at the measurement periods. The EC losses over 7 and 14 days were 3.7% and 19.9% in Sinasol against 4.6% and 20.8% in Optisol-GS. Although fair quality corneas were more common in Optisol-GS group after 7 (P = 0.04) and 14 days (P = 0.034), changes of stromal edema, Descemet's fold, and other quality ratings during 14 days were not different between the groups. In phase II, all the transplanted corneas were postoperatively clear with no adverse reactions. The overall results indicate that Sinasol is a safe, effective, and affordable intermediate cold storage medium for preservation of corneas.

MicroRNAs may provide new strategies in the treatment and diagnosis of diabetic retinopathy: Importance of VEGF.

Diabetic retinopathy (DR) is ocular microvascular complications of diabetes mellitus. Along with the increasing prevalence of diabetes worldwide, DR has come into the major cause of human blindness. Several studies have demonstrated the important roles of the expression alteration in the proteins contributed to vascular dysfunction during DR, especially vascular endothelial growth factor (VEGF). However, there is a need for further mechanistic research in this context to design new therapeutic and diagnostic programs. MicroRNAs (miRNAs, miRs) have been introduced as key controllers of gene expression in a variety of biological processes including differentiation, proliferation, and metabolism. Altered expression of miRNAs during DR development indicates a close relationship between these regulatory molecules and DR through regulating gene expressions. This review discusses and updates the functions of miRNA-dependent pathways and key roles of VEGF in the DR, which may increase our understanding and ability to target these small but important molecules to efficiently improve therapeutic and diagnostic approaches.

Impression cytology for detection of clinically suspected ocular surface disorders: A cross-sectional study.

PURPOSE: Investigating impression cytology (IC) results of various types of clinically suspected ocular surface lesions over a 14-year period in a referral center in Iran. METHODS: IC findings obtained from patients with different types of ocular surface disorders between 2005 and 2018 were reviewed. Agreement between clinical suspicions and IC results was evaluated by calculating Cohen's Kappa coefficient (CKC). RESULTS: Clinical suspicions in 688 surveyed eyes were ocular surface squamous neoplasia (OSSN, 42.0%), limbal stem cell deficiency (LSCD, 36.3%), dry eye-related disorders (DERD, 11.5%), Acanthamoeba keratitis (AK, 7.2%), benign pigmented lesions (BPL, 1.9%), immune-related conjunctivitis (IRC, 0.7%), and malignant pigmented lesions (MPL, 0.4%). General agreement between clinical suspicions and IC results was 0.68 for all groups. This agreement was almost perfect in AK (CKC = 0.966) and BPLs (CKC = 0.843), and was substantial in MPLs (CKC = 0.749), OSSNs (CKC = 0.684), and LSCD (CKC = 0.612). CKC in IRC (0.567) and DERDs (0.443) was moderate. Histopathologic results were available in 22 eyes and were well-correlated with corresponding IC results (CKC = 0.86). Multiple post-treatment follow-up sessions of IC were performed in 51 eyes (11.4%) that had diagnosis of LSCD (31), OSSN (17), and MPL (3) at the first IC session. CONCLUSION: Our survey not only demonstrated an overall substantial agreement between IC results and primary clinical suspicions, but also showed an almost perfect correlation between IC results and existent histopathologic data. Therefore, IC as a non-invasive diagnostic modality can be of great importance in proper diagnosis of various ocular surface diseases especially when distinguishing malignant from benign lesions is required.

In Vivo Effect of RSH-12, a Novel Selective MMP-9 Inhibitor Peptide, in the Treatment of Experimentally Induced Dry Eye Model.

PURPOSE: To investigate the efficacy of RSH-12, a novel selective matrix metalloproteinase 9 (MMP-9) inhibitor peptide in rabbit models of dry eye syndrome (DES). METHODS: In vitro toxicity of RSH-12 on cultured human corneal fibroblasts was investigated with MTT. Ocular toxicity of RSH-12 was investigated by clinical examinations, histology, and TUNEL assay. Experimental model of dry eye was induced by 1.0% atropine sulfate administration followed after 15 min by treatment with PBS, RSH-12, and Restasis in individual groups, three times a day for 7 days. In addition to performing Schirmer's test for evaluating basic tear secretion and tear break-up time test for investigating tear stability, the occurrence of superficial punctate keratopathy was also investigated in the study groups. RESULTS: MTT assay demonstrated that RSH-12 was not toxic to human corneal fibroblasts in different concentrations. During the administration of atropine, TBUT values and tear volume were decreased in vehicle group while these indices improved significantly in groups treated with RSH-12 in a promising manner. RSH-12 increased the mean value of tear volume from 4.85 to 10.75 mm (P = .0001) and mean of TBUT values from 20.3 s to 34.5 s (P = .0001) compared with the vehicle. In contrast to the presence of severe superficial punctate keratopathy in the controls, no significant dotted staining was observed in the RSH-12 and Restasis groups. CONCLUSIONS: These outcomes propose that RSH-12 has a therapeutic effect in the rabbit model of dry eye and might be a potential treatment for severe DES.

A mutation in DOP1B identified as a probable cause for autosomal recessive Peters anomaly in a consanguineous family.

Purpose: Peters anomaly (PA) is a heterogeneous developmental disorder characterized by central corneal opacity and iridocorneal or corneolenticular adhesions. Although many causative genes have been identified, most screened patients do not have mutations in the known genes. We aimed to identify the genetic cause of Peters anomaly in a pedigree with three affected individuals. Methods: Slit-lamp biomicroscopy and ultrasound biomicroscopy were performed for definitive diagnosis. Exome sequencing was conducted on the DNA of all three patients. After identification of a candidate causative gene, expression of the gene was assessed with real-time PCR in various ocular tissues of three human embryos and three adults. Results: The patients were affected with isolated PA. The parents of the patients were related to one another. Inheritance of PA was autosomal recessive. After appropriate filtering of the exome data, a homozygous variation in DOP1B remained as the only candidate genetic cause of PA in the pedigree. The variant segregated with disease status in the pedigree and was absent among 800 control Iranians. The variant has been reported in various databases at frequencies of 0.006 or less only in the heterozygous state in some cohorts of African origin. The p.Val1660 amino acid affected by the mutation is completely conserved in mammals and birds during evolution. Expression of DOP1B was shown in all adult and embryonic lens, iris, cornea, sclera, and retina tissues that were tested. Conclusions: DOP1B that encodes DOP1 leucine zipper like protein B was identified as the putative PA-causing gene in pedigree PA-101. As DOP1B is positioned within the Down syndrome chromosomal region on chromosome 21, until now this gene has mostly been studied with respect to brain functions. However, members of the Dopey gene family have been shown to have roles in development in other organisms. Evidence of the expression of DOP1B in various PA-relevant eye tissues, which, to the best of our knowledge, is shown here for the first time, is to be noted. However, this finding does not necessarily implicate a specific role for DOP1B in eye development as the gene is expressed in many tissues. Ultimately, definitive assessment of the contribution of DOP1B to PA pathology awaits identification of mutations in the gene in unrelated patients with PA and functional studies.

Preparation of endothelial keratoplasty lenticules with Gebauer SLc Original versus Moria CBm Carriazo-Barraquer and Moria One-Use Plus microkeratomes.

Purpose: To investigate endothelial keratoplasty lenticules prepared from fresh whole eyes via Gebauer SLc Original (SLc) versus Moria CBm Carriazo-Barraquer (CBm), and those prepared from corneoscleral buttons via SLc versus Moria One-Use Plus (OUP) in terms of eye bank preparation criteria. Methods: Fresh whole eyes-dissected endothelial keratoplasty lenticules with SLc were compared with CBm in terms of thickness profile measurements, over/under dissection values, endothelial cell loss, and postoperative graft failures. A similar comparison was made between corneoscleral buttons-dissected endothelial keratoplasty lenticules with SLc and OUP. Results: Means of central thicknesses and increase of thickness toward periphery were not significantly different between 33 fresh whole eyes-dissected endothelial keratoplasty lenticules with SLc and 33 fresh whole eyes-dissected ones with CBm. There was no significant difference between 19 corneoscleral buttons-dissected endothelial keratoplasty lenticules with SLc and 19 corneoscleral buttons-dissected ones with OUP in terms of mean central thickness and post-cut endothelial cell loss. However, in the corneoscleral buttons-dissected endothelial keratoplasty lenticules, a mean increase of thickness was significantly different from central to two pericentral locations with OUP (P = 0.001) and from central to two peripheral parts with SLc (P = 0.011). Both CBm and OUP systems showed deeper dissection depths than head descriptions as compared to SLc (P < 0.001). Conclusion: Unlike fresh whole eyes-dissected endothelial keratoplasty lenticules with SLc or CBm, thickness profiles of corneoscleral buttons-dissected endothelial keratoplasty lenticules with both SLc and OUP systems showed a partial asymmetric increase of thickness toward the periphery. A high agreement was observed between endothelial keratoplasty lenticules thicknesses and SLc nomograms.