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Tao BKL, Hassanlou M, Ong Tone S. Corneal ulcer as the presenting sign of prolonged contact lens retention over 25 years. Can J Ophthalmol 2024; 59:e272-e274. [PMID: 38154486 DOI: 10.1016/j.jcjo.2023.12.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2023] [Revised: 11/02/2023] [Accepted: 12/03/2023] [Indexed: 12/30/2023]
Affiliation(s)
| | - Mojgan Hassanlou
- Sunnybrook Research Institute, Toronto, ON; Department of Ophthalmology and Vision Sciences, University of Toronto, Toronto, ON
| | - Stephan Ong Tone
- Department of Ophthalmology and Vision Sciences, University of Toronto, Toronto, ON; Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON.
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2
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Yan J, Mehta S, Patel K, Dhupar N, Little N, Ong Tone S. Transcription factor 4 promotes increased corneal endothelial cellular migration by altering microtubules in Fuchs endothelial corneal dystrophy. Sci Rep 2024; 14:10276. [PMID: 38704483 PMCID: PMC11069521 DOI: 10.1038/s41598-024-61170-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2024] [Accepted: 05/02/2024] [Indexed: 05/06/2024] Open
Abstract
Fuchs endothelial corneal dystrophy (FECD) is a complex corneal disease characterized by the progressive decline and morphological changes of corneal endothelial cells (CECs) that leads to corneal edema and vision loss. The most common mutation in FECD is an intronic CTG repeat expansion in transcription factor 4 (TCF4) that leads to its altered expression. Corneal endothelial wound healing occurs primarily through cell enlargement and migration, and FECD CECs have been shown to display increased migration speeds. In this study, we aim to determine whether TCF4 can promote cellular migration in FECD CECs. We generated stable CEC lines derived from FECD patients that overexpressed different TCF4 isoforms and investigated epithelial-to-mesenchymal (EMT) expression, morphological analysis and cellular migration speeds. We found that full length TCF4-B isoform overexpression promotes cellular migration in FECD CECs in an EMT-independent manner. RNA-sequencing identified several pathways including the negative regulation of microtubules, with TUBB4A (tubulin beta 4A class IVa) as the top upregulated gene. TUBB4A expression was increased in FECD ex vivo specimens, and there was altered expression of cytoskeleton proteins, tubulin and actin, compared to normal healthy donor ex vivo specimens. Additionally, there was increased acetylation and detyrosination of microtubules in FECD supporting that microtubule stability is altered in FECD and could promote cellular migration. Future studies could be aimed at investigating if targeting the cytoskeleton and microtubules would have therapeutic potential for FECD by promoting cellular migration and regeneration.
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Affiliation(s)
- Judy Yan
- Sunnybrook Health Sciences Center and Sunnybrook Research Institute, 2075 Bayview Avenue, M-wing, 1st Floor, Toronto, ON, M4N 3M5, Canada
| | - Shanti Mehta
- Sunnybrook Health Sciences Center and Sunnybrook Research Institute, 2075 Bayview Avenue, M-wing, 1st Floor, Toronto, ON, M4N 3M5, Canada
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Canada
| | - Keya Patel
- Sunnybrook Health Sciences Center and Sunnybrook Research Institute, 2075 Bayview Avenue, M-wing, 1st Floor, Toronto, ON, M4N 3M5, Canada
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Canada
| | - Narisa Dhupar
- Sunnybrook Health Sciences Center and Sunnybrook Research Institute, 2075 Bayview Avenue, M-wing, 1st Floor, Toronto, ON, M4N 3M5, Canada
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Canada
| | - Ness Little
- Sunnybrook Health Sciences Center and Sunnybrook Research Institute, 2075 Bayview Avenue, M-wing, 1st Floor, Toronto, ON, M4N 3M5, Canada
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Canada
| | - Stephan Ong Tone
- Sunnybrook Health Sciences Center and Sunnybrook Research Institute, 2075 Bayview Avenue, M-wing, 1st Floor, Toronto, ON, M4N 3M5, Canada.
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Canada.
- Department of Ophthalmology and Vision Sciences, University of Toronto, Toronto, Canada.
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Cohen E, Ong Tone S, Mimouni M, Stein R, Chan CC, Chew HF, Rabinovitch T, Rootman DS, Slomovic AR, Hatch WV, Singal N. Comparison of long-term outcomes of simultaneous accelerated corneal crosslinking combined with intracorneal ring segment or topography-guided PRK. J Cataract Refract Surg 2024; 50:378-384. [PMID: 38015419 DOI: 10.1097/j.jcrs.0000000000001369] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2023] [Accepted: 11/13/2023] [Indexed: 11/29/2023]
Abstract
PURPOSE To compare long-term outcomes of simultaneous accelerated corneal crosslinking (CXL) with intrastromal corneal ring segments (CXL-ICRS) with simultaneous accelerated CXL with topography-guided photorefractive keratectomy (CXL-TG-PRK) in progressive keratoconus (KC). SETTING Kensington Eye Institute and Bochner Eye Institute, Toronto, Canada. DESIGN Prospective nonrandomized interventional study. METHODS The change in visual and topographical outcomes of CXL-ICRS and CXL-TG-PRK 4 to 5 years postoperatively were compared using linear regression models adjusted for preoperative corrected distance visual acuity (CDVA) and maximum keratometry (Kmax). RESULTS 57 eyes of 43 patients with progressive KC who underwent simultaneous accelerated (9 mW/cm 2 , 10 minutes) CXL-ICRS (n = 32) and CXL-TG-PRK (n = 25) were included. Mean follow-up duration was 51.28 (9.58) and 54.57 (5.81) months for the CXL-ICRS and CXL-TG-PRK groups, respectively. Initial mean Kmax was higher in the CXL-ICRS group compared with the CXL-TG-PRK group (60.68 ± 6.81 diopters [D] vs 57.15 ± 4.19 D, P = .02). At the last follow-up, change (improvement) in logMAR uncorrected distance visual acuity (UDVA) compared with that preoperatively was significant with CXL-ICRS (-0.31 ± 0.27, P < .001, which is equivalent to approximately 3 lines) and not significant with CXL-TG-PRK (-0.06 ± 0.42, P = .43). The logMAR CDVA improved significantly with CXL-ICRS (-0.22 ± 0.20, P < .001), but not with CXL-TG-PRK (-0.05 ± 0.22, P = .25). Adjusting for baseline Kmax and CDVA, the improvement in UDVA was significantly greater with CXL-ICRS than with CXL-TG-PRK (-0.27, 95% CI, 0.06-0.47, P = .01). Improvement in CDVA was not significantly different. CONCLUSIONS In this cohort of progressive KC with long-term follow-up, UDVA showed more improvement with accelerated CXL-ICRS than with CXL-TG-PRK.
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Affiliation(s)
- Eyal Cohen
- From the Department of Ophthalmology and Vision Sciences, University of Toronto, Toronto, Canada (Cohen, Tone, Mimouni, Stein, Chan, Chew, Rabinovitch, Rootman, Slomovic, Hatch, Singal); Division of Ophthalmology, Tel Aviv Sourasky Medical Center, Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel (Cohen); Department of Ophthalmology, Rambam Health Care Campus affiliated with the Bruce and Ruth Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa, Israel (Mimouni)
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Dhupar N, AlShaker S, Chai J, Yan J, Little N, Humphreys C, Chan CC, Ong Tone S. Validation of preloaded DMEK donor tissues: a laboratory-based study on endothelial cell viability and comparison of two F-mark inks. Can J Ophthalmol 2024:S0008-4182(24)00062-0. [PMID: 38513716 DOI: 10.1016/j.jcjo.2024.02.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/08/2023] [Revised: 12/24/2023] [Accepted: 02/25/2024] [Indexed: 03/23/2024]
Abstract
OBJECTIVE To investigate endothelial cell loss (ECL) associated with Descemet membrane endothelial keratoplasty (DMEK) donor tissues preloaded in the DMEK RAPID transport system after 1 and 5 days and to compare prestamping with 2 different F-mark inks. METHODS DMEK donor tissues were stripped, marked with gentian violet dye applied as an F-mark, trephined, stained with trypan blue, and then preloaded into the DMEK RAPID transport system by an eye bank technician. Preloaded DMEK tissues were then unfolded and stained with calcein AM after 1 or 5 days of storage. Tissues were imaged, analyzed for total tissue ECL, and immunostained for corneal endothelium markers zonular occludens-1 and xCD166. Additionally, ECL and the intensity of an F-mark caused by 2 different inks were quantified. RESULTS Preloaded DMEK tissues displayed an average ECL of 11.9% ± 4.5% (n = 8) at 1 day and 9.9% ± 4.2% (n = 9) at 5 days. No difference was found between the 2 groups. Zonular occludens-1 and activated leukocyte cell adhesion molecule (ALCAM; also know as CD166) staining showed that the corneal endothelial monolayer remained intact on preloaded tissues. On 5-day preloaded DMEK tissues, the average ECL and mean grayscale caused by the Keir Surgical ink F-mark and the Cardinal Health ink F-mark were 4.3% ± 0.8% and 158.5 ± 13.9% and 5.0% ± 1.1% and 142.9% ± 20.0%, respectively. No difference was found between the F-mark inks. CONCLUSION Preloaded DMEK donor tissues resulted in an acceptable ECL range after 1 and 5 days of storage and were deemed suitable for transplantation. Both F-mark inks are acceptable for prestamping preloaded DMEK tissues prior to surgical transplantation with comparable ECL and intensities.
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Affiliation(s)
- Narisa Dhupar
- Sunnybrook Research Institute, Toronto, ON; Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON
| | - Sara AlShaker
- Department of Ophthalmology and Vision Sciences, University of Toronto, Toronto, ON; Department of Ophthalmology, College of Medicine, King Saud University, Riyadh, Saudi Arabia
| | - Jenny Chai
- Eye Bank of Canada Ontario Division, Toronto, ON
| | - Judy Yan
- Sunnybrook Research Institute, Toronto, ON
| | - Ness Little
- Sunnybrook Research Institute, Toronto, ON; Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON
| | | | - Clara C Chan
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON; Eye Bank of Canada Ontario Division, Toronto, ON
| | - Stephan Ong Tone
- Sunnybrook Research Institute, Toronto, ON; Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON; Department of Ophthalmology and Vision Sciences, University of Toronto, Toronto, ON.
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Pandey PU, Ballios BG, Christakis PG, Kaplan AJ, Mathew DJ, Ong Tone S, Wan MJ, Micieli JA, Wong JCY. Ensemble of deep convolutional neural networks is more accurate and reliable than board-certified ophthalmologists at detecting multiple diseases in retinal fundus photographs. Br J Ophthalmol 2024; 108:417-423. [PMID: 36720585 PMCID: PMC10894841 DOI: 10.1136/bjo-2022-322183] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2022] [Accepted: 01/11/2023] [Indexed: 02/02/2023]
Abstract
AIMS To develop an algorithm to classify multiple retinal pathologies accurately and reliably from fundus photographs and to validate its performance against human experts. METHODS We trained a deep convolutional ensemble (DCE), an ensemble of five convolutional neural networks (CNNs), to classify retinal fundus photographs into diabetic retinopathy (DR), glaucoma, age-related macular degeneration (AMD) and normal eyes. The CNN architecture was based on the InceptionV3 model, and initial weights were pretrained on the ImageNet dataset. We used 43 055 fundus images from 12 public datasets. Five trained ensembles were then tested on an 'unseen' set of 100 images. Seven board-certified ophthalmologists were asked to classify these test images. RESULTS Board-certified ophthalmologists achieved a mean accuracy of 72.7% over all classes, while the DCE achieved a mean accuracy of 79.2% (p=0.03). The DCE had a statistically significant higher mean F1-score for DR classification compared with the ophthalmologists (76.8% vs 57.5%; p=0.01) and greater but statistically non-significant mean F1-scores for glaucoma (83.9% vs 75.7%; p=0.10), AMD (85.9% vs 85.2%; p=0.69) and normal eyes (73.0% vs 70.5%; p=0.39). The DCE had a greater mean agreement between accuracy and confident of 81.6% vs 70.3% (p<0.001). DISCUSSION We developed a deep learning model and found that it could more accurately and reliably classify four categories of fundus images compared with board-certified ophthalmologists. This work provides proof-of-principle that an algorithm is capable of accurate and reliable recognition of multiple retinal diseases using only fundus photographs.
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Affiliation(s)
- Prashant U Pandey
- School of Biomedical Engineering, The University of British Columbia, Vancouver, British Columbia, Canada
| | - Brian G Ballios
- Department of Ophthalmology and Vision Sciences, University of Toronto, Toronto, Ontario, Canada
- Krembil Research Institute, University Health Network, Toronto, Ontario, Canada
- Kensington Vision and Research Centre and Kensington Research Institute, Toronto, Ontario, Canada
| | - Panos G Christakis
- Department of Ophthalmology and Vision Sciences, University of Toronto, Toronto, Ontario, Canada
- Kensington Vision and Research Centre and Kensington Research Institute, Toronto, Ontario, Canada
| | - Alexander J Kaplan
- Department of Ophthalmology and Vision Sciences, University of Toronto, Toronto, Ontario, Canada
| | - David J Mathew
- Department of Ophthalmology and Vision Sciences, University of Toronto, Toronto, Ontario, Canada
- Krembil Research Institute, University Health Network, Toronto, Ontario, Canada
- Kensington Vision and Research Centre and Kensington Research Institute, Toronto, Ontario, Canada
| | - Stephan Ong Tone
- Department of Ophthalmology and Vision Sciences, University of Toronto, Toronto, Ontario, Canada
- Sunnybrook Research Institute, Toronto, Ontario, Canada
| | - Michael J Wan
- Department of Ophthalmology and Vision Sciences, University of Toronto, Toronto, Ontario, Canada
| | - Jonathan A Micieli
- Department of Ophthalmology and Vision Sciences, University of Toronto, Toronto, Ontario, Canada
- Kensington Vision and Research Centre and Kensington Research Institute, Toronto, Ontario, Canada
- Department of Ophthalmology, St. Michael's Hospital, Unity Health, Toronto, Ontario, Canada
| | - Jovi C Y Wong
- Department of Ophthalmology and Vision Sciences, University of Toronto, Toronto, Ontario, Canada
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Jurkunas UV, Yin J, Johns LK, Li S, Negre H, Shaw KL, Samarakoon L, Ayala AR, Kheirkhah A, Katikireddy K, Gauthier A, Ong Tone S, Kaufman AR, Ellender S, Hernandez Rodriguez DE, Daley H, Dana R, Armant M, Ritz J. Cultivated autologous limbal epithelial cell (CALEC) transplantation: Development of manufacturing process and clinical evaluation of feasibility and safety. Sci Adv 2023; 9:eadg6470. [PMID: 37595035 PMCID: PMC10438443 DOI: 10.1126/sciadv.adg6470] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2023] [Accepted: 07/18/2023] [Indexed: 08/20/2023]
Abstract
To treat unilateral limbal stem cell (LSC) deficiency, we developed cultivated autologous limbal epithelial cells (CALEC) using an innovative xenobiotic-free, serum-free, antibiotic-free, two-step manufacturing process for LSC isolation and expansion onto human amniotic membrane with rigorous quality control in a good manufacturing practices facility. Limbal biopsies were used to generate CALEC constructs, and final grafts were evaluated by noninvasive scanning microscopy and tested for viability and sterility. Cultivated cells maintained epithelial cell phenotype with colony-forming and proliferative capacities. Analysis of LSC biomarkers showed preservation of "stemness." After preclinical development, a phase 1 clinical trial enrolled five patients with unilateral LSC deficiency. Four of these patients received CALEC transplants, establishing preliminary feasibility. Clinical case histories are reported, with no primary safety events. On the basis of these results, a second recruitment phase of the trial was opened to provide longer term safety and efficacy data on more patients.
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Affiliation(s)
- Ula V. Jurkunas
- Department of Ophthalmology, Massachusetts Eye and Ear, Harvard Medical School, Boston, MA, USA
| | - Jia Yin
- Department of Ophthalmology, Massachusetts Eye and Ear, Harvard Medical School, Boston, MA, USA
| | - Lynette K. Johns
- Department of Ophthalmology, Massachusetts Eye and Ear, Harvard Medical School, Boston, MA, USA
| | - Sanming Li
- Department of Ophthalmology, Massachusetts Eye and Ear, Harvard Medical School, Boston, MA, USA
| | - Helene Negre
- Connell and O'Reilly Families Cell Manipulation Core Facility, Dana-Farber Cancer Institute, Boston, MA, USA
| | - Kit L. Shaw
- Connell and O'Reilly Families Cell Manipulation Core Facility, Dana-Farber Cancer Institute, Boston, MA, USA
| | | | | | - Ahmad Kheirkhah
- Department of Ophthalmology, Massachusetts Eye and Ear, Harvard Medical School, Boston, MA, USA
| | - Kishore Katikireddy
- Department of Ophthalmology, Massachusetts Eye and Ear, Harvard Medical School, Boston, MA, USA
| | - Alex Gauthier
- Department of Ophthalmology, Massachusetts Eye and Ear, Harvard Medical School, Boston, MA, USA
| | - Stephan Ong Tone
- Department of Ophthalmology, Massachusetts Eye and Ear, Harvard Medical School, Boston, MA, USA
| | - Aaron R. Kaufman
- Department of Ophthalmology, Massachusetts Eye and Ear, Harvard Medical School, Boston, MA, USA
| | - Stacey Ellender
- Department of Ophthalmology, Massachusetts Eye and Ear, Harvard Medical School, Boston, MA, USA
| | | | - Heather Daley
- Connell and O'Reilly Families Cell Manipulation Core Facility, Dana-Farber Cancer Institute, Boston, MA, USA
| | - Reza Dana
- Department of Ophthalmology, Massachusetts Eye and Ear, Harvard Medical School, Boston, MA, USA
| | - Myriam Armant
- TransLab, Translational Research Program, Boston Children’s Hospital, Boston, MA, USA
| | - Jerome Ritz
- Connell and O'Reilly Families Cell Manipulation Core Facility, Dana-Farber Cancer Institute, Boston, MA, USA
- Department of Medical Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA, USA
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7
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Stein R, Ong Tone S, Lebovic G, Singal N, Hatch W. Subjective and objective evaluation of corneal haze after accelerated corneal crosslinking for corneal ectasias. Acta Ophthalmol 2023. [PMID: 36707973 DOI: 10.1111/aos.15639] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2022] [Revised: 12/12/2022] [Accepted: 01/08/2023] [Indexed: 01/29/2023]
Abstract
PURPOSE To evaluate the relationship between subjective (slit lamp examination [SLE]) and objective (densitometry) measurements of corneal haze after accelerated corneal crosslinking (aCXL), assess the relationship between densitometry and corrected distance visual acuity (CDVA), and determine the effect of baseline characteristics on densitometry after aCXL in eyes with progressive keratoconus and other ectasias. SETTING Kensington Eye Institute and Bochner Eye Institute, Toronto, Canada. DESIGN Retrospective analysis of a prospective interventional cohort study. METHODS Scheimpflug-derived corneal densitometry, CDVA, maximum keratometry (Kmax ), and central corneal thickness were measured preoperatively and up to 1 year after aCXL, and post-operative haze was estimated with SLE (n = 483 eyes). A random effect model was used to examine the relationship between post-operative subjective haze with SLE and densitometry. Linear mixed models were used to examine the relationship between densitometry, pre-operative baseline characteristics, and CDVA. RESULTS There was a significant association between subjective haze with SLE and densitometry (p < 0.001). There was a significant relationship between CDVA and densitometry: for every 10 GSUs of increased densitometry in the 0-2 mm zone, CDVA worsened by approximately half a Snellen line (p < 0.001). Age and pre-operative Kmax were significant predictors of densitometry. For every 10 years of age, densitometry increased by 0.68 GSUs (95% CI [0.27 to 1.07], p < 0.001). For every 10 D of increased preoperative Kmax , densitometry increased by 0.69 GSUs (95% CI [0.41 to 0.98], p < 0.001). CONCLUSIONS Subjective haze after aCXL estimated with SLE, is significantly associated with densitometry. Increased densitometry after aCXL is associated with a reduction in CDVA.
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Affiliation(s)
- Rebecca Stein
- Kensington Eye Institute, Toronto, Ontario, Canada.,Department of Ophthalmology and Vision Sciences, University of Toronto, Toronto, Ontario, Canada
| | - Stephan Ong Tone
- Kensington Eye Institute, Toronto, Ontario, Canada.,Department of Ophthalmology and Vision Sciences, University of Toronto, Toronto, Ontario, Canada.,Kensington Crosslinking Working Group, Toronto, Ontario, Canada.,Sunnybrook Health Sciences Centre and Sunnybrook Research Institute, Toronto, Ontario, Canada
| | | | - Neera Singal
- Kensington Eye Institute, Toronto, Ontario, Canada.,Department of Ophthalmology and Vision Sciences, University of Toronto, Toronto, Ontario, Canada.,Kensington Crosslinking Working Group, Toronto, Ontario, Canada
| | - Wendy Hatch
- Kensington Eye Institute, Toronto, Ontario, Canada.,Department of Ophthalmology and Vision Sciences, University of Toronto, Toronto, Ontario, Canada
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8
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Din N, Cohen E, Popovic M, Mimouni M, Trinh T, Gouvea L, Alshaker S, Ong Tone S, Chan CC, Slomovic AR. Surgical Management of Fuchs Endothelial Corneal Dystrophy: A Treatment Algorithm and Individual Patient Meta-Analysis of Descemet Stripping Only. Cornea 2022; 41:1188-1195. [PMID: 35942547 DOI: 10.1097/ico.0000000000002975] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2021] [Accepted: 11/23/2021] [Indexed: 11/27/2022]
Abstract
PURPOSE This study aims to determine predictive factors for success of Descemet stripping only (DSO) in Fuchs corneal endothelial dystrophy and propose a DSO treatment algorithm. METHODS Ovid MEDLINE, Embase, and Cochrane CENTRAL databases were searched to evaluate DSO case series, including combined phacoemulsification and DSO, and the use of Rho-kinase inhibitors (ROC-i). Our primary outcome was success of corneal clearance. Secondary outcomes included the time to corneal clearance, the postoperative endothelial cell count (ECC), and the impact of ROC-i. RESULTS Sixty-eight cases were evaluated with a mean follow-up of 12.4 months. DSO corneal clearance was achieved in 85% (n = 58) with a mean time of 4.9 weeks for the ROC-i group compared with 10.1 weeks in the observation group (P < 0.0001). The mean central ECC postoperatively was higher in the ROC-i group compared with the observation group 1151 ± 245 versus 765 ± 169 cells/mm2, respectively (P < 0.018). The postoperative best-corrected visual acuity (BCVA) improved in 61 eyes (90%), with mean final BCVA of 0.17 (0.26) logMAR (P = 0.001), which was statistically significant compared with preoperative BCVA. Factors influencing success were 4-mm descemetorhexis size, a clear peripheral ECC with no clinical sequelae of decompensation or guttae, and a low central corneal thickness. No intraoperative complications were noted. The commonest postoperative complication was deep corneal stromal scars noted at the descemetorhexis edge (n = 9). CONCLUSIONS DSO has a role in the treatment of a subset of patients with Fuchs corneal endothelial dystrophy and that adjuvant treatment with ROC-i may lead to faster corneal clearance.
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Affiliation(s)
- Nizar Din
- Department of Ophthalmology and Vision Sciences, University of Toronto, Toronto, Canada
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9
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Bal S, Laíns I, Chiou C, Patel N, Rudnik ND, Kim CB, Ma KK, Tone SO, Begaj T, Lu Y, Armstrong GW. Video-based surgical curriculum for open globe injury repair, IV: corneal wounds. Digit J Ophthalmol 2022; 28:86-99. [PMID: 36660184 PMCID: PMC9838177 DOI: 10.5693/djo.01.2022.08.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
As one of the most severe forms of ocular trauma, open-globe injury (OGI) causes significant vision loss. Timely and meticulous repair of these injuries can improve patient outcomes. This video-based educational curriculum is intended to serve as an efficient, yet comprehensive reference for OGI repair. We hope that these video-based articles help surgeons and trainees from around the world find answers to specific surgical questions in OGI management. The curriculum has been divided into six separate review articles, each authored by a different set of authors, to facilitate a systematic and practical approach to the subject of wound types and repair techniques. This fourth article highlights special considerations in the repair of open-globe injuries affecting the anterior chamber and cornea.
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Affiliation(s)
- Sila Bal
- Department of Ophthalmology, Harvard Medical School, Boston, Massachusetts
- Massachusetts Eye and Ear, Boston, Massachusetts
| | - Inês Laíns
- Department of Ophthalmology, Harvard Medical School, Boston, Massachusetts
- Massachusetts Eye and Ear, Boston, Massachusetts
| | - Carolina Chiou
- Department of Ophthalmology, Harvard Medical School, Boston, Massachusetts
- Massachusetts Eye and Ear, Boston, Massachusetts
| | - Neal Patel
- Department of Ophthalmology, Harvard Medical School, Boston, Massachusetts
- Massachusetts Eye and Ear, Boston, Massachusetts
| | - Noam D. Rudnik
- Department of Ophthalmology, Harvard Medical School, Boston, Massachusetts
- Massachusetts Eye and Ear, Boston, Massachusetts
| | - Clifford B. Kim
- Department of Ophthalmology, Harvard Medical School, Boston, Massachusetts
- Massachusetts Eye and Ear, Boston, Massachusetts
| | - Kevin K. Ma
- Department of Ophthalmology, Harvard Medical School, Boston, Massachusetts
- Massachusetts Eye and Ear, Boston, Massachusetts
| | - Stephan Ong Tone
- Department of Ophthalmology and Vision Sciences, Sunnybrook Health Sciences Centre, Toronto, Ontario
| | | | - Tedi Begaj
- Department of Ophthalmology, Harvard Medical School, Boston, Massachusetts
- Massachusetts Eye and Ear, Boston, Massachusetts
| | - Yifan Lu
- Massachusetts Eye and Ear, Boston, Massachusetts
- Cambridge Health Alliance, Harvard Medical School, Cambridge, Massachusetts
| | - Grayson W. Armstrong
- Department of Ophthalmology, Harvard Medical School, Boston, Massachusetts
- Massachusetts Eye and Ear, Boston, Massachusetts
- Correspondence: Grayson W. Armstrong, MD, MPH, Department of Ophthalmology, Harvard Medical School, Massachusetts Eye and Ear, Boston, MA ()
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10
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Begaj T, Ong Tone S, Ciolino JB. Toxic Keratoconjunctivitis from Coral Reef. Case Rep Ophthalmol 2021; 12:694-698. [PMID: 34594206 PMCID: PMC8436652 DOI: 10.1159/000517350] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2021] [Accepted: 05/11/2021] [Indexed: 11/19/2022] Open
Abstract
A 25-year-old woman presented with right eye pain, lid edema, conjunctival injection and chemosis, and mild corneal epitheliopathy after exposure to fluid content from an aquarium coral reef. Topical moxifloxacin and prednisolone were started 4 times daily, with full clinical resolution after 2 weeks. Toxin-mediated keratoconjunctivitis may occur after exposure to zoanthid coral reef, particularly in aquarium enthusiasts. Topical corticosteroids in tandem with topical antibiotics appear to be effective in mild disease. However, in severe cases that exhibit corneal infiltrates and stromal thinning, close observation is warranted in case of possible keratolysis.
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Affiliation(s)
- Tedi Begaj
- Department of Ophthalmology, Massachusetts Eye and Ear, Harvard Medical School, Boston, Massachusetts, USA
| | - Stephan Ong Tone
- Cornea and External Eye Disease, Sunnybrook Health Sciences Centre and Sunnybrook Research Institute, Department of Ophthalmology and Vision Sciences, University of Toronto, Toronto, Ontario, Canada
| | - Joseph B Ciolino
- Department of Ophthalmology, Massachusetts Eye and Ear, Harvard Medical School, Boston, Massachusetts, USA
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Mantena S, Chandra J, Pecyna E, Zhang A, Garrity D, Ong Tone S, Sastry S, Uddaraju M, Jurkunas UV. Low-Cost, Smartphone-Based Specular Imaging and Automated Analysis of the Corneal Endothelium. Transl Vis Sci Technol 2021; 10:4. [PMID: 34003981 PMCID: PMC8024782 DOI: 10.1167/tvst.10.4.4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Purpose Specular and confocal microscopes are important tools to monitor the health of the corneal endothelium (CE), but their high costs significantly limit accessibility in low-resource environments. We developed and validated a low-cost, fully automated method to quantitatively evaluate the CE using smartphone-based specular microscopy. Methods A OnePlus 7 Pro smartphone attached to a Topcon SL-D701 slit-lamp was used to image the central corneal endothelium of 30 eyes using the specular reflection technique. A novel on-device image processing algorithm automatically computed endothelial cell density (ECD), percentage of hexagonal cells (HEX), and coefficient of variation (CV) values. These values were compared with the ECD, HEX, and CV generated by a Tomey EM-4000 specular microscope used to image the same set of eyes. Results No significant differences were found in ECD (2799 ± 156 cells/mm2 vs. 2779 ± 166 cells/mm2; P = 0.28) and HEX (52 ± 6% vs. 53 ± 6%; P = 0.50) computed by smartphone-based specular imaging and specular microscope, respectively. A statistically significant difference in CV (34 ± 3% vs. 30 ± 3%; P < 0.01) was found between the two methods. The concordance achieved between the smartphone-based method and the Tomey specular microscope is very similar to the concordance between two specular microscopes reported in the literature. Conclusions Smartphone-based specular imaging and automated analysis is a low-cost method to quantitatively evaluate the CE with accuracy comparable to the clinical standard. Translational Relevance This tool can be used to screen the CE in low-resource regions and prompt investigation of suspected corneal endotheliopathies.
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Affiliation(s)
- Sreekar Mantena
- Harvard John A. Paulson School of Engineering and Applied Science, Cambridge, MA, USA.,Global Alliance for Medical Innovation, Cambridge, MA, USA
| | - Jay Chandra
- Harvard John A. Paulson School of Engineering and Applied Science, Cambridge, MA, USA.,Global Alliance for Medical Innovation, Cambridge, MA, USA
| | - Eryk Pecyna
- Harvard John A. Paulson School of Engineering and Applied Science, Cambridge, MA, USA.,Global Alliance for Medical Innovation, Cambridge, MA, USA
| | - Andrew Zhang
- Harvard John A. Paulson School of Engineering and Applied Science, Cambridge, MA, USA.,Global Alliance for Medical Innovation, Cambridge, MA, USA
| | - Dominic Garrity
- Harvard John A. Paulson School of Engineering and Applied Science, Cambridge, MA, USA.,Global Alliance for Medical Innovation, Cambridge, MA, USA
| | - Stephan Ong Tone
- Cornea Center of Excellence, Schepens Eye Research Institute, Harvard Medical School, Boston, MA, USA.,Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, MA, USA.,Department of Ophthalmology, Harvard Medical School, Boston, MA, USA.,Sunnybrook Health Sciences Centre and Sunnybrook Research Institute, Department of Ophthalmology and Vision Sciences, University of Toronto, Toronto, Ontario, Canada
| | | | - Madhu Uddaraju
- Sri Kiran Institute of Ophthalmology, Kakinada, Andhra Pradesh, India
| | - Ula V Jurkunas
- Cornea Center of Excellence, Schepens Eye Research Institute, Harvard Medical School, Boston, MA, USA.,Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, MA, USA.,Department of Ophthalmology, Harvard Medical School, Boston, MA, USA
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12
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Ong Tone S, Wylegala A, Böhm M, Melangath G, Deshpande N, Jurkunas UV. Increased Corneal Endothelial Cell Migration in Fuchs Endothelial Corneal Dystrophy: A Live Cell Imaging Study. Ophthalmol Sci 2021; 1:100006. [PMID: 36246012 PMCID: PMC9559113 DOI: 10.1016/j.xops.2021.100006] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/11/2020] [Revised: 02/09/2021] [Accepted: 03/03/2021] [Indexed: 12/13/2022]
Abstract
Purpose To investigate if corneal endothelial cells (CECs) in Fuchs endothelial corneal dystrophy (FECD) have altered cellular migration compared with normal controls. Design Comparative analysis. Materials Descemet's membrane and CECs derived from patients with FECD undergoing endothelial keratoplasty or normal cadaveric donors. Methods Ex vivo specimens were used for live cell imaging and generation of immortalized cell lines. Live imaging was performed on FECD and normal CECs and on ex vivo specimens transfected with green fluorescent protein. Migration speeds were determined as a function of cellular density using automated cell tracking. Ex vivo specimens were classified as either FECD or normal low cell density (nonconfluent) or high cell density (confluent). Scratch assay was performed on CECs seeded at high confluence to determine migration speed. Genetic analysis from blood samples or CECs was performed to detect a CTG repeat expansion in the TCF4 gene. Main Outcome Measures Mean cell migration speed. Results Fuchs endothelial corneal dystrophy CECs in low cell density areas displayed increased mean speed (0.391 ± 0.005 μm/minute vs. 0.364 ± 0.005 μm/minute; P < 0.001) and mean maximum speed (0.961 ± 0.010 μm/minute vs. 0.787 ± 0.011 μm/minute; P < 0.001) compared with normal CECs, and increased mean maximum speed (0.778 ± 0.014 μm/minute vs. 0.680 ± 0.011 μm/minute; P < 0.001) in high cell density areas ex vivo. Similarly, FECD CECs displayed increased mean speed compared with normal CECs (1.958 ± 0.020 μm/minute vs. 2.227 ± 0.021 μm/minute vs. 1.567 ± 0.019 μm/minute; P < 0.001) under nonconfluent conditions in vitro. Moreover, FECD CECs also displayed increased mean speed compared with normal CECs under high confluent conditions as detected by scratch assay (37.2 ± 1.1% vs. 44.3 ± 4.1% vs. 70.7 ± 5.2%; P < 0.001). Morphologic analysis showed that FECD CECs displayed an increased fibroblastic phenotype as detected by filamentous-actin labeling. Conclusions Fuchs endothelial corneal dystrophy CECs demonstrated increased migration speed compared with normal CECs. Further investigation into the mechanisms of heightened cell migration in FECD is needed and may provide insight into its pathogenesis, as well as having implications on descemetorhexis without endothelial keratoplasty.
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Key Words
- CE, corneal endothelium
- CEC, corneal endothelial cell
- Cell migration
- Corneal endothelium
- DM, Descemet’s membrane
- DMEK, Descemet's membrane endothelial keratoplasty
- DWEK, descemetorhexis without endothelial keratoplasty
- Descemetorhexis without endothelial keratoplasty
- Descemet’s stripping only
- ECD, endothelial cell density
- ECM, extracellular matrix
- EMT, endothelial-to-mesenchymal transition
- FECD, Fuchs endothelial corneal dystrophy
- Fuchs endothelial corneal dystrophy
- GFP, green fluorescent protein
- LNP, lipid nanoparticle
- PBS, phosphate-buffered saline
- TCF4, transcription factor 4
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Affiliation(s)
- Stephan Ong Tone
- Cornea Center of Excellence, Schepens Eye Research Institute, Harvard Medical School, Boston, Massachusetts
- Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, Massachusetts
- Department of Ophthalmology, Harvard Medical School, Boston, Massachusetts
- Sunnybrook Health Sciences Centre, Sunnybrook Research Institute, Toronto, Canada
- Department of Ophthalmology, University of Toronto, Toronto, Canada
| | - Adam Wylegala
- Cornea Center of Excellence, Schepens Eye Research Institute, Harvard Medical School, Boston, Massachusetts
- Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, Massachusetts
- Department of Ophthalmology, Harvard Medical School, Boston, Massachusetts
| | - Myriam Böhm
- Cornea Center of Excellence, Schepens Eye Research Institute, Harvard Medical School, Boston, Massachusetts
- Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, Massachusetts
- Department of Ophthalmology, Harvard Medical School, Boston, Massachusetts
| | - Geetha Melangath
- Cornea Center of Excellence, Schepens Eye Research Institute, Harvard Medical School, Boston, Massachusetts
- Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, Massachusetts
- Department of Ophthalmology, Harvard Medical School, Boston, Massachusetts
| | - Neha Deshpande
- Cornea Center of Excellence, Schepens Eye Research Institute, Harvard Medical School, Boston, Massachusetts
- Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, Massachusetts
- Department of Ophthalmology, Harvard Medical School, Boston, Massachusetts
| | - Ula V. Jurkunas
- Cornea Center of Excellence, Schepens Eye Research Institute, Harvard Medical School, Boston, Massachusetts
- Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, Massachusetts
- Department of Ophthalmology, Harvard Medical School, Boston, Massachusetts
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13
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Böhm M, Leon P, Wylęgała A, Ong Tone S, Condron T, Jurkunas U. Cost-effectiveness analysis of preloaded versus non-preloaded Descemet membrane endothelial keratoplasty for the treatment of Fuchs endothelial corneal dystrophy in an academic centre. Br J Ophthalmol 2021; 106:914-922. [PMID: 33637619 DOI: 10.1136/bjophthalmol-2020-317536] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2020] [Revised: 01/19/2021] [Accepted: 02/05/2021] [Indexed: 11/04/2022]
Abstract
AIMS To determine the cost-effectiveness of preloaded Descemet membrane endothelial keratoplasty (pDMEK) versus non-preloaded DMEK (n-pDMEK) for the treatment of Fuchs endothelial corneal dystrophy (FECD). METHODS From a societal and healthcare perspective, this retrospective cost-effectiveness analysis analysed a cohort of 58 patients with FECD receiving pDMEK (n=38) or n-pDMEK (n=30) from 2016 to 2018 in the Department of Ophthalmology, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, USA. Exclusion criteria were previous ocular surgeries (other than uncomplicated cataract surgery), including other keratoplasty procedures, ocular pathological conditions as glaucoma, amblyopia, laser treatments, or any retinal or corneal disease. The main outcome parameters were the incremental cost-utility ratio (ICUR) and net monetary benefit (NMB). RESULTS pDMEK was less costly compared with n-pDMEK (healthcare: $13 886 vs $15 329; societal: $20 805 vs $22 262), with a slighter greater utility (QALY 0.6682 vs QALY 0.6640) over a time horizon of 15 years. pDMEK offered a slightly higher clinical effectiveness (+0.0042 QALY/patient) at a lower cost (healthcare: -$1444 per patient; societal: -$1457 per patient) in improving visual acuity in this cohort of patients with FECD. pDMEK achieved a favourable ICUR and NMB compared with n-pDMEK. Based on sensitivity analyses performed, the economic model was robust. CONCLUSIONS From the societal and healthcare perspective, pDMEK was less costly and generated comparable utility values relative to n-pDMEK. Therefore, pDMEK appears to be cost-effective and cost saving with respect to n-pDMEK. Further long-term follow-up data are needed to confirm these findings.
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Affiliation(s)
- Myriam Böhm
- Department of Ophthalmology, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, Massachusetts, USA.,Department of Ophthalmology, Goethe University Frankfurt, Frankfurt am Main, Germany
| | - Pia Leon
- Department of Ophthalmology, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, Massachusetts, USA
| | - Adam Wylęgała
- Department of Ophthalmology, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, Massachusetts, USA
| | - Stephan Ong Tone
- Department of Ophthalmology, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, Massachusetts, USA
| | - Tracy Condron
- Department of Ophthalmology, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, Massachusetts, USA
| | - Ula Jurkunas
- Department of Ophthalmology, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, Massachusetts, USA
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14
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Ong Tone S, Kocaba V, Böhm M, Wylegala A, White TL, Jurkunas UV. Fuchs endothelial corneal dystrophy: The vicious cycle of Fuchs pathogenesis. Prog Retin Eye Res 2021; 80:100863. [PMID: 32438095 PMCID: PMC7648733 DOI: 10.1016/j.preteyeres.2020.100863] [Citation(s) in RCA: 74] [Impact Index Per Article: 24.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2019] [Revised: 04/05/2020] [Accepted: 04/10/2020] [Indexed: 12/13/2022]
Abstract
Fuchs endothelial corneal dystrophy (FECD) is the most common primary corneal endothelial dystrophy and the leading indication for corneal transplantation worldwide. FECD is characterized by the progressive decline of corneal endothelial cells (CECs) and the formation of extracellular matrix (ECM) excrescences in Descemet's membrane (DM), called guttae, that lead to corneal edema and loss of vision. FECD typically manifests in the fifth decades of life and has a greater incidence in women. FECD is a complex and heterogeneous genetic disease where interaction between genetic and environmental factors results in cellular apoptosis and aberrant ECM deposition. In this review, we will discuss a complex interplay of genetic, epigenetic, and exogenous factors in inciting oxidative stress, auto(mito)phagy, unfolded protein response, and mitochondrial dysfunction during CEC degeneration. Specifically, we explore the factors that influence cellular fate to undergo apoptosis, senescence, and endothelial-to-mesenchymal transition. These findings will highlight the importance of abnormal CEC-DM interactions in triggering the vicious cycle of FECD pathogenesis. We will also review clinical characteristics, diagnostic tools, and current medical and surgical management options for FECD patients. These new paradigms in FECD pathogenesis present an opportunity to develop novel therapeutics for the treatment of FECD.
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Affiliation(s)
- Stephan Ong Tone
- Cornea Center of Excellence, Schepens Eye Research Institute, Harvard Medical School, Boston, MA, United States; Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, MA, United States; Department of Ophthalmology, Harvard Medical School, Boston, MA, United States
| | - Viridiana Kocaba
- Cornea Center of Excellence, Schepens Eye Research Institute, Harvard Medical School, Boston, MA, United States; Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, MA, United States; Department of Ophthalmology, Harvard Medical School, Boston, MA, United States
| | - Myriam Böhm
- Cornea Center of Excellence, Schepens Eye Research Institute, Harvard Medical School, Boston, MA, United States; Department of Ophthalmology, Harvard Medical School, Boston, MA, United States
| | - Adam Wylegala
- Cornea Center of Excellence, Schepens Eye Research Institute, Harvard Medical School, Boston, MA, United States; Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, MA, United States; Department of Ophthalmology, Harvard Medical School, Boston, MA, United States
| | - Tomas L White
- Cornea Center of Excellence, Schepens Eye Research Institute, Harvard Medical School, Boston, MA, United States; Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, MA, United States; Department of Ophthalmology, Harvard Medical School, Boston, MA, United States
| | - Ula V Jurkunas
- Cornea Center of Excellence, Schepens Eye Research Institute, Harvard Medical School, Boston, MA, United States; Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, MA, United States; Department of Ophthalmology, Harvard Medical School, Boston, MA, United States.
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15
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Hatch W, El-Defrawy S, Ong Tone S, Stein R, Slomovic AR, Rootman DS, Rabinovitch T, Kranemann C, Chew HF, Chan CC, Bujak MC, Cohen A, Lebovic G, Jin Y, Singal N. Accelerated Corneal Cross-Linking: Efficacy, Risk of Progression, and Characteristics Affecting Outcomes. A Large, Single-Center Prospective Study. Am J Ophthalmol 2020; 213:76-87. [PMID: 31945333 DOI: 10.1016/j.ajo.2020.01.006] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2019] [Revised: 01/02/2020] [Accepted: 01/03/2020] [Indexed: 10/25/2022]
Abstract
PURPOSE We examined the efficacy and preoperative characteristics that affect outcomes of accelerated (9 mW/cm2 for 10 minutes) corneal cross-linking (CXL). DESIGN Prospective single-center observational cohort study. METHODS We enrolled 612 eyes of 391 subjects with progressive keratoconus (n = 589), pellucid marginal degeneration (n = 11), and laser in situ keratomileusis-induced ectasia (n = 12). We evaluated best spectacle-corrected visual acuity (BSCVA), topography, refraction, endothelial cell density, corneal thickness, haze, intraocular pressure, and visual function before and 12 months after the CXL procedure. We tabulated the proportion of those with progression of maximum keratometry (Kmax). We included participant's race, age, sex, and the presence of preoperative apical scarring and environmental allergies in a multivariable linear regression model to determine the effect of these characteristics on outcomes. RESULTS At 1 year there was no significant change in mean Kmax (n = 569). Progression of Kmax was higher in subgroups with a baseline Kmax >58 diopters (n = 191) and those 14-18 years of age (n = 53). Preoperative BSCVA, Kmax, refraction, corneal cylinder, coma, central corneal thickness, and vision function were statistically and clinically significant predictors of outcomes (P < .001). Preoperative apical scarring led to worsening haze (P = .0001), more astigmatism (P = .002), more central corneal thinning (P = .002), and was protective to the endothelium (P = .008). Race, age, and sex affected some outcomes. CONCLUSION Mean Kmax was stable at 1 year after accelerated CXL. Younger patients and those with a higher preoperative Kmax need to be monitored closely for progression. Preoperative BSCVA, topography, refraction, CCT, and apical scarring were significant predictors of outcomes.
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16
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Liu C, Miyajima T, Melangath G, Miyai T, Vasanth S, Deshpande N, Kumar V, Ong Tone S, Gupta R, Zhu S, Vojnovic D, Chen Y, Rogan EG, Mondal B, Zahid M, Jurkunas UV. Ultraviolet A light induces DNA damage and estrogen-DNA adducts in Fuchs endothelial corneal dystrophy causing females to be more affected. Proc Natl Acad Sci U S A 2020; 117:573-583. [PMID: 31852820 PMCID: PMC6955350 DOI: 10.1073/pnas.1912546116] [Citation(s) in RCA: 60] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Fuchs endothelial corneal dystrophy (FECD) is a leading cause of corneal endothelial (CE) degeneration resulting in impaired visual acuity. It is a genetically complex and age-related disorder, with higher incidence in females. In this study, we established a nongenetic FECD animal model based on the physiologic outcome of CE susceptibility to oxidative stress by demonstrating that corneal exposure to ultraviolet A (UVA) recapitulates the morphological and molecular changes of FECD. Targeted irradiation of mouse corneas with UVA induced reactive oxygen species (ROS) production in the aqueous humor, and caused greater CE cell loss, including loss of ZO-1 junctional contacts and corneal edema, in female than male mice, characteristic of late-onset FECD. UVA irradiation caused greater mitochondrial DNA (mtDNA) and nuclear DNA (nDNA) damage in female mice, indicative of the sex-driven differential response of the CE to UVA, thus accounting for more severe phenotype in females. The sex-dependent effect of UVA was driven by the activation of estrogen-metabolizing enzyme CYP1B1 and formation of reactive estrogen metabolites and estrogen-DNA adducts in female but not male mice. Supplementation of N-acetylcysteine (NAC), a scavenger of reactive oxygen species (ROS), diminished the morphological and molecular changes induced by UVA in vivo. This study investigates the molecular mechanisms of environmental factors in FECD pathogenesis and demonstrates a strong link between UVA-induced estrogen metabolism and increased susceptibility of females for FECD development.
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Affiliation(s)
- Cailing Liu
- Schepens Eye Research Institute of Massachusetts Eye and Ear, Boston, MA 02114
- Department of Ophthalmology, Harvard Medical School, Boston, MA 02115
| | - Taiga Miyajima
- Schepens Eye Research Institute of Massachusetts Eye and Ear, Boston, MA 02114
- Department of Ophthalmology, Harvard Medical School, Boston, MA 02115
| | - Geetha Melangath
- Schepens Eye Research Institute of Massachusetts Eye and Ear, Boston, MA 02114
- Department of Ophthalmology, Harvard Medical School, Boston, MA 02115
| | - Takashi Miyai
- Schepens Eye Research Institute of Massachusetts Eye and Ear, Boston, MA 02114
- Department of Ophthalmology, Harvard Medical School, Boston, MA 02115
| | - Shivakumar Vasanth
- Schepens Eye Research Institute of Massachusetts Eye and Ear, Boston, MA 02114
- Department of Ophthalmology, Harvard Medical School, Boston, MA 02115
| | - Neha Deshpande
- Schepens Eye Research Institute of Massachusetts Eye and Ear, Boston, MA 02114
- Department of Ophthalmology, Harvard Medical School, Boston, MA 02115
| | - Varun Kumar
- Schepens Eye Research Institute of Massachusetts Eye and Ear, Boston, MA 02114
- Department of Ophthalmology, Harvard Medical School, Boston, MA 02115
| | - Stephan Ong Tone
- Schepens Eye Research Institute of Massachusetts Eye and Ear, Boston, MA 02114
- Department of Ophthalmology, Harvard Medical School, Boston, MA 02115
| | - Reena Gupta
- Schepens Eye Research Institute of Massachusetts Eye and Ear, Boston, MA 02114
- Department of Ophthalmology, Harvard Medical School, Boston, MA 02115
| | - Shan Zhu
- Schepens Eye Research Institute of Massachusetts Eye and Ear, Boston, MA 02114
- Department of Ophthalmology, Harvard Medical School, Boston, MA 02115
| | - Dijana Vojnovic
- Schepens Eye Research Institute of Massachusetts Eye and Ear, Boston, MA 02114
- Department of Ophthalmology, Harvard Medical School, Boston, MA 02115
| | - Yuming Chen
- Schepens Eye Research Institute of Massachusetts Eye and Ear, Boston, MA 02114
- Department of Ophthalmology, Harvard Medical School, Boston, MA 02115
| | - Eleanor G Rogan
- Department of Environmental, Agricultural and Occupational Health, College of Public Health, University of Nebraska Medical Center, Omaha, NE 68198-4388
| | - Bodhiswatta Mondal
- Department of Environmental, Agricultural and Occupational Health, College of Public Health, University of Nebraska Medical Center, Omaha, NE 68198-4388
| | - Muhammad Zahid
- Department of Environmental, Agricultural and Occupational Health, College of Public Health, University of Nebraska Medical Center, Omaha, NE 68198-4388
| | - Ula V Jurkunas
- Schepens Eye Research Institute of Massachusetts Eye and Ear, Boston, MA 02114;
- Department of Ophthalmology, Harvard Medical School, Boston, MA 02115
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Abstract
Fuchs endothelial corneal dystrophy (FECD) is characterized by the progressive degeneration of the corneal endothelium (CE). The purpose of this article is to review the diagnostic tools available to image and assess the CE in FECD. Slit-lamp biomicroscopy with specular reflection and retroillumination are important techniques to assess the CE. Objective diagnostic tests, such as retroillumination photographic analysis, specular microscopy, in vivo confocal microscopy (IVCM), and anterior segment optical coherence tomography, are valuable tools to evaluate the CE in FECD. Specular microscopy can be performed rapidly without touching the eye but requires a clear cornea with a smooth CE. In contrast, IVCM can image all layers of the cornea, even in advanced FECD. However, IVCM is contact-based and more technically challenging. It is important to select the appropriate objective diagnostic test to image and assess the CE in managing patients with FECD.
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Affiliation(s)
- Stephan Ong Tone
- Schepens Eye Research Institute, Massachusetts Eye and Ear, Harvard Medical School, Boston, MA USA
| | - Ula Jurkunas
- Schepens Eye Research Institute, Massachusetts Eye and Ear, Harvard Medical School, Boston, MA USA
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18
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Ong Tone S, Bruha MJ, Böhm M, Prescott C, Jurkunas U. Regional variability in corneal endothelial cell density between guttae and non-guttae areas in Fuchs endothelial corneal dystrophy. Can J Ophthalmol 2019; 54:570-576. [PMID: 31564347 DOI: 10.1016/j.jcjo.2018.12.009] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2018] [Revised: 12/07/2018] [Accepted: 12/31/2018] [Indexed: 10/26/2022]
Abstract
OBJECTIVE To assess the regional variability of corneal endothelial cell density (ECD) between guttae and non-guttae areas in subjects with Fuchs endothelial corneal dystrophy (FECD) using non-contact specular microscopy and confocal microscopy. DESIGN Retrospective chart review from 2009 to 2014 at the Massachusetts Eye and Ear Infirmary. PARTICIPANTS One hundred fifteen eyes of 73 subjects with FECD. METHODS Subjects with FECD underwent same-day specular and confocal microscopy in the same eye. Clinical stage of disease was documented on the day of image acquisition. Regional variability of ECD associated with guttae and non-guttae areas was assessed. Manual endothelial cell counts were performed. RESULTS Thirty-two percent of subjects had high quality endothelial images by both specular and confocal microscopy. Of these subjects, 83% were classified clinically as early-stage FECD. There was a significant association between stage of disease and the ability to obtain high quality specular images (χ2; p = 0.0012). There was no difference in mean ECD derived from specular (1363 ± 594 cells/mm2) or confocal (1391 ± 493 cells/mm2; p = 0.75) images. There was a statistically significant decrease of 31.8 ± 21.7% in mean ECD in areas surrounding guttae (1296 ± 560 cells/mm2) compared to non-guttae areas (1926 ± 674 cells/mm2; p < 0.0001) as determined by confocal microscopy. CONCLUSION These findings support confocal microscopy as an alternative to specular microscopy for evaluating the corneal endothelium of patients with FECD, especially those with advanced disease. Confocal microscopy also revealed regional differences in ECD in guttae and non-guttae areas in patients with FECD.
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Affiliation(s)
- Stephan Ong Tone
- Schepens Eye Research Institute, Massachusetts Eye and Ear, Boston, Mass
| | | | - Myriam Böhm
- Schepens Eye Research Institute, Massachusetts Eye and Ear, Boston, Mass
| | | | - Ula Jurkunas
- Schepens Eye Research Institute, Massachusetts Eye and Ear, Boston, Mass.
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19
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Grzybowski A, Schwartz SG, Matsuura K, Ong Tone S, Arshinoff S, Ng JQ, Meyer JJ, Liu W, Jacob S, Packer M, Lutfiamida R, Tahija S, Roux P, Malyugin B, Urrets-Zavalia JA, Crim N, Esposito E, Daponte P, Pellegrino F, Graue-Hernandez EO, Jimenez-Corona A, Valdez-Garcia JE, Hernandez-Camarena JC, Relhan N, Flynn HW, Ravindran RD, Behnding A. Endophthalmitis Prophylaxis in Cataract Surgery: Overview of Current Practice Patterns Around the World. Curr Pharm Des 2017; 23:565-573. [PMID: 27981903 DOI: 10.2174/1381612822666161216122230] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2016] [Accepted: 12/08/2016] [Indexed: 11/22/2022]
Abstract
BACKGROUND Acute-onset postoperative endophthalmitis after cataract surgery remains a rare but important cause of visual loss. There is no global consensus regarding the optimal strategies for prophylaxis of endophthalmitis and practices vary substantially around the world, especially with respect to the use of intracameral antibiotics. The European Society of Cataract & Refractive Surgeons in a randomized clinical trial (2007) reported an approximately 5-fold reduction in endophthalmitis rates associated with the use of intracameral cefuroxime. Despite this report, the use of intracameral antibiotics has not been universally adopted. METHODS Various endophthalmitis prophylaxis patterns around the world (including the United States, Canada, Australia/New Zealand, Japan, China, India, Indonesia, South Africa, Argentina, Russia, Sweden and Mexico) are compared. Each contributing author was asked to provide similar information, including endophthalmitis rates based on published studies, current practice patterns, and in some cases original survey data. Various methods were used to obtain this information, including literature reviews, expert commentary, and some new survey data not previously published. RESULTS Many different practice patterns were reported from around the world, specifically with respect to the use of intracameral antibiotics. CONCLUSION There is no worldwide consensus regarding endophthalmitis prophylaxis with cataract surgery.
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Affiliation(s)
- Andrzej Grzybowski
- Professor of Ophthalmology, Department of Ophthalmology Poznan City Hospital, Ul. Szwajcarska 3, 60- 285, Poznan. Poland
| | - Stephen G Schwartz
- Department of Ophthalmology, University of Warmia and Mazury, Olsztyn. Poland
| | - Kazuki Matsuura
- Department of Ophthalmology, Nojima Hospital, Tottori. Japan
| | - Stephan Ong Tone
- Department of Ophthalmology and Vision Sciences, University of Toronto, Toronto, ON. United States
| | - Steve Arshinoff
- Division of Ophthalmology, McMaster University, Hamilton, ON. Canada
| | - Jonathon Q Ng
- Eye and Vision Epidemiology Research Group, The University of Western Australia Perth. Australia
| | - Jay J Meyer
- Department of Ophthalmology, University of Auckland. New Zealand
| | - Wu Liu
- Department of Ophthalmology, Beijing Tongren Hospital Eye Center, Capital Medical University Beijing. China
| | | | - Mark Packer
- Department of Ophthalmology, Oregon Health & Science University, Portland, Oregon. United States
| | | | | | - Paul Roux
- Visionmed Eye and Laser Clinic, Johannesburg. South Africa
| | - Boris Malyugin
- S. Fyodorov Eye Microsurgery State Institution, Moscow. Russian Federation
| | - Julio A Urrets-Zavalia
- Department of Ophthalmology, University Clinic Reina Fabiola, Catholic University of Cordoba. Argentina
| | - Nicolas Crim
- Department of Ophthalmology, University Clinic Reina Fabiola, Catholic University of Cordoba. Argentina
| | - Evangelina Esposito
- Department of Ophthalmology, University Clinic Reina Fabiola, Catholic University of Cordoba. Argentina
| | - Pablo Daponte
- Argentine Council of Ophthalmology, Buenos Aires. Argentina
| | - Fernando Pellegrino
- Department of Ophthalmology, Santa Lucia Hospital, University of Buenos Aires. Argentina
| | | | - Aida Jimenez-Corona
- Instituto de Oftalmologia Fundacion Conde de Valenciana, Mexico City. Mexico
| | | | | | - Nidhi Relhan
- Department of Ophthalmology, Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, FL. United States
| | - Harry W Flynn
- Department of Ophthalmology, Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, FL. United States
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Ong Tone S, DeAngelis D, Monteiro E, Witterick I. Nasopharyngeal carcinoma presenting with no light perception vision. Can J Ophthalmol 2016; 51:e39-40. [PMID: 27085271 DOI: 10.1016/j.jcjo.2015.10.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2015] [Revised: 09/22/2015] [Accepted: 10/04/2015] [Indexed: 11/16/2022]
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Kaplan A, Ong Tone S, Fournier AE. Extrinsic and intrinsic regulation of axon regeneration at a crossroads. Front Mol Neurosci 2015; 8:27. [PMID: 26136657 PMCID: PMC4470051 DOI: 10.3389/fnmol.2015.00027] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2015] [Accepted: 06/03/2015] [Indexed: 11/16/2022] Open
Abstract
Repair of the injured spinal cord is a major challenge in medicine. The limited intrinsic regenerative response mounted by adult central nervous system (CNS) neurons is further hampered by astrogliosis, myelin debris and scar tissue that characterize the damaged CNS. Improved axon regeneration and recovery can be elicited by targeting extrinsic factors as well as by boosting neuron-intrinsic growth regulators. Our knowledge of the molecular basis of intrinsic and extrinsic regulators of regeneration has expanded rapidly, resulting in promising new targets to promote repair. Intriguingly certain neuron-intrinsic growth regulators are emerging as promising targets to both stimulate growth and relieve extrinsic inhibition of regeneration. This crossroads between the intrinsic and extrinsic aspects of spinal cord injury is a promising target for effective therapies for this unmet need.
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Affiliation(s)
- Andrew Kaplan
- Department of Neurology/Neurosurgery, Montréal Neurological Institute, McGill University Montréal, QC, Canada
| | - Stephan Ong Tone
- Department of Neurology/Neurosurgery, Montréal Neurological Institute, McGill University Montréal, QC, Canada
| | - Alyson E Fournier
- Department of Neurology/Neurosurgery, Montréal Neurological Institute, McGill University Montréal, QC, Canada
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Khazaei MR, Girouard MP, Alchini R, Ong Tone S, Shimada T, Bechstedt S, Cowan M, Guillet D, Wiseman PW, Brouhard G, Cloutier JF, Fournier AE. Collapsin response mediator protein 4 regulates growth cone dynamics through the actin and microtubule cytoskeleton. J Biol Chem 2014; 289:30133-43. [PMID: 25225289 PMCID: PMC4208019 DOI: 10.1074/jbc.m114.570440] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2014] [Revised: 09/10/2014] [Indexed: 12/22/2022] Open
Abstract
Coordinated control of the growth cone cytoskeleton underlies axon extension and guidance. Members of the collapsin response mediator protein (CRMP) family of cytosolic phosphoproteins regulate the microtubule and actin cytoskeleton, but their roles in regulating growth cone dynamics remain largely unexplored. Here, we examine how CRMP4 regulates the growth cone cytoskeleton. Hippocampal neurons from CRMP4-/- mice exhibited a selective decrease in axon extension and reduced growth cone area, whereas overexpression of CRMP4 enhanced the formation and length of growth cone filopodia. Biochemically, CRMP4 can impact both microtubule assembly and F-actin bundling in vitro. Through a structure function analysis of CRMP4, we found that the effects of CRMP4 on axon growth and growth cone morphology were dependent on microtubule assembly, whereas filopodial extension relied on actin bundling. Intriguingly, anterograde movement of EB3 comets, which track microtubule protrusion, slowed significantly in neurons derived from CRMP4-/- mice, and rescue of microtubule dynamics required CRMP4 activity toward both the actin and microtubule cytoskeleton. Together, this study identified a dual role for CRMP4 in regulating the actin and microtubule growth cone cytoskeleton.
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Affiliation(s)
- Mohamad R Khazaei
- From the Department of Neurology and Neurosurgery, Montréal Neurological Institute, 3801 Rue University, Montréal, Québec H3A 2B4, Canada
| | - Marie-Pier Girouard
- From the Department of Neurology and Neurosurgery, Montréal Neurological Institute, 3801 Rue University, Montréal, Québec H3A 2B4, Canada
| | - Ricardo Alchini
- From the Department of Neurology and Neurosurgery, Montréal Neurological Institute, 3801 Rue University, Montréal, Québec H3A 2B4, Canada
| | - Stephan Ong Tone
- From the Department of Neurology and Neurosurgery, Montréal Neurological Institute, 3801 Rue University, Montréal, Québec H3A 2B4, Canada
| | - Tadayuki Shimada
- Neural Plasticity Project, Tokyo Metropolitan Institute of Medical Science, 2-1-6 Kamikitazawa, Setagaya-ku, Tokyo 156-8506, Japan
| | | | - Mitra Cowan
- Centre de recherche du Centre hospitalier de l'Université de Montréal, Montréal H2X 0A9, Canada
| | | | - Paul W Wiseman
- Department of Physics, McGill University, Montréal H3A 2T8, Canada, Department of Chemistry, McGill University, Montréal H3A 2K6, Canada, and
| | - Gary Brouhard
- Department of Biology, McGill University, Montréal H3G 0B1, Canada
| | - Jean Francois Cloutier
- From the Department of Neurology and Neurosurgery, Montréal Neurological Institute, 3801 Rue University, Montréal, Québec H3A 2B4, Canada
| | - Alyson E Fournier
- From the Department of Neurology and Neurosurgery, Montréal Neurological Institute, 3801 Rue University, Montréal, Québec H3A 2B4, Canada,
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Khazaei MR, Montcalm S, Di Polo A, Fournier AE, Durocher Y, Ong Tone S. Development of a cell permeable competitive antagonist of RhoA and CRMP4 binding, TAT-C4RIP, to promote neurite outgrowth. J Mol Neurosci 2014; 55:406-15. [PMID: 25015230 DOI: 10.1007/s12031-014-0350-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2013] [Accepted: 06/05/2014] [Indexed: 11/24/2022]
Abstract
Neurons fail to re-extend their processes within the central nervous system environment in vivo, and this is partly because of inhibitory proteins expressed within myelin debris and reactive astrocytes that actively signal to the injured nerve cells to limit their growth. The ability of the trans-acting activator of transcription (TAT) protein transduction domain (PTD) to transport macromolecules across biological membranes raises the possibility of developing it as a therapeutic delivery tool for nerve regeneration. Most studies have produced TAT PTD fusion protein in bacteria, which can result in problems such as protein solubility, the formation of inclusion bodies and the lack of eukaryotic posttranslational modifications. While some groups have investigated the production of TAT PTD fusion protein in mammalian cells, these strategies are focused on generating TAT PTD fusions that are targeted to the secretory pathway, where furin protease as well as other proteases can cleave the TAT PTD. As an alternative to mutating the furin cleavage site in the TAT PTD, we describe a novel method to generate cytosolic TAT PTD fusion proteins and purify them from cell lysates. Here, we use this method to generate TAT-C4RIP, a cell permeable competitive antagonist of binding between the small GTPase RhoA and the cytosolic phosphoprotein Collapsin response mediator protein 4 (CRMP4). We demonstrate that TAT-C4RIP transduces cells in vitro and in vivo and retains its biological activity to attenuate myelin inhibition in an in vitro neurite outgrowth assay.
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Ong Tone S, Godra A, Ing E. Polyangiitis overlap syndrome with granulomatosis with polyangiitis (Wegener’s) and giant cell arteritis. Can J Ophthalmol 2013; 48:e6-8. [DOI: 10.1016/j.jcjo.2012.08.018] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2012] [Revised: 07/23/2012] [Accepted: 08/28/2012] [Indexed: 11/16/2022]
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Abstract
The Clinician Investigator Trainee Association of Canada – Association des cliniciens-chercheurs en formation du Canada (CITAC-ACCFC) is a national organization composed of MD+ trainees enrolled in MD/MSc, MD/PhD, and Clinician Investigator Programs (CIP) across Canada. In less than three years since its conception, CITAC-ACCFC has become an established organization with over 200 members from fifteen academic institutions. The mission of the CITAC-ACCFC is to organize and promote activities that support clinician investigator trainees in Canada, with the intention to improve academic and post-graduate career opportunities, expand institutional and public awareness of clinician investigator programs, and develop a nationally accessible information database of student and program development. The CITAC-ACCFC aims to improve the early-career conditions of clinician investigators in order to expand and advance innovative research initiatives within Canada. Throughout its development, CITAC-ACCFC has relied on the Canadian Society for Clinical Investigation (CSCI) for mentorship and guidance. In an exciting development, the relationship between CITAC-ACCFC and CSCI has enabled an innovative opportunity for early career development through a new collaboration- the creation of a Trainee Section in the Clinical and Investigative Medicine (CIM) journal.
As a forum through which work on diverse topics can be shared with the global community, the CIM Trainee Section will create unique opportunities for professional development. Trainees in MD+ programs represent the next generation of clinical-investigators, who will integrate cutting edge research and compassionate patient care throughout their careers. Both professions require excellent communication skills, and through the Trainee Section, MD+ trainees, their supervisors, and MD+ Program Directors, will be able to focus on mentorship, academic training, financial planning, and career development, among other topics devoted to MD+ trainees. In addition to articles highlighting the research activities of trainees, the Trainee Section will feature clinical work, review articles, first chapter of theses, book reviews, and opinion pieces. This focus of the Trainee Section will complement CIM’s current focus on original research and issues of interest to the CSCI. It is therefore fitting to establish a Trainee Section that is dedicated to addressing issues arising at an earlier stage of training. As MD+ organizations are being established globally, the Trainee Section will strive to become an international forum that focuses on MD+ training. By increasing the international readership of CIM through the CITAC website, we will aim to engage MD+ trainees, program directors, university administration, and other leaders in education, to advocate for issues of national and global relevance.
As trainees will be responsible for overseeing the editorial and peer-review process of the Trainee Section, we anticipate that this will provide an avenue by which to foster stronger interactions and collaborations among trainees on our Editorial Board, junior investigators, and senior faculty, while providing critical editorial experience for board members. Our team of Editors will ensure that articles are reviewed in a fair and timely manner, respecting the need to promptly publish articles of immediate relevance. We encourage all MD+ trainees to participate in the Trainee Section editorial and/or peer-review process. Additional details can be found on our website at:
http://www.citac-accfc.org/portal/
As MD+ trainees, we are optimistic about the future of both basic science and clinical research. This is an exciting time to be an MD+ trainee, and we are confident that the creation of a Trainee Section will only augment this positive experience. We strongly encourage you to publish your work in the Trainee Section and become part of an emerging global community of MD+ trainees, who are keen on tackling health issues that affect us irrespective of our geographic, cultural, or racial borders.
We look forward to receiving your articles.
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Ong Tone S, Dugani S, Marshall H, Shamji MF, Murray JC, Bossé D. Survol du programme scientifique du congrès annuel de la SCRC-ACCFC 2009. CLIN INVEST MED 2010. [DOI: 10.25011/cim.v33i1.11841] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Du 21 au 23 septembre 2009 a eu lieu à Ottawa le congrès annuel de l’Association des cliniciens-chercheurs en formation du Canada – Clinical Investigator Trainee Association of Canada (ACCFC-CITAC) et de la Société canadienne de recherche clinique (SCRC). Parmi les participants se trouvaient des cliniciens-chercheurs et des étudiants en provenance des quatre coins du pays.
Cette conférence mettait à l’avant-plan des invités de marque, dont le récipiendaire actuel du Prix international de la recherche en santé Henry G. Friesen, Sir John Bell. Plusieurs tables rondes entourant le développement professionnel s’y tenaient, avec des sujets tels que « le support des cliniciens-chercheurs canadiens », « le succès des cliniciens-chercheurs » et « la collaboration internationale des MD+ en formation », tout en donnant l’opportunité d’établir des liens avec des mentors et collaborateurs potentiels. De plus, le congrès annuel de l’ACCFC-CITAC mettait en vedette plusieurs recherches impliquant des MD+ en formation à travers tout le Canada, dans le cadre de la séance de présentation par affiches du Forum des jeunes chercheurs ou lors de la séance plénière.
Ce survol vise à mettre en évidence certaines des recherches présentées par les chercheurs en formation lors de la conférence annuelle, autant sur le plan de la recherche fondamentale que de la recherche clinique. Dans cet article, nous résumons les principales questions de recherche abordées par ces cliniciens-chercheurs en formation dans les disciplines suivantes : neurosciences, biologie cellulaire, médecine, immunologie, obstétrique, gynécologie, néonatalogie, orthopédie, rhumatologie et santé publique.
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Dugani S, Ong Tone S. La création d'une Section étudiante dans le CIM. CLIN INVEST MED 2010. [DOI: 10.25011/cim.v33i1.11831] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
L’Association des cliniciens-chercheurs en formation du Canada – the Clinician Investigator Trainee Association of Canada (ACCFC-CITAC) est une organisation nationale composée de MD+ en formation, inscrits dans un programme MD/MSc, MD/PhD ou clinicien-chercheur (PCC) à travers le Canada. Depuis sa création il y a moins de trois ans, l’ACCFC-CITAC est devenue une organisation bien établie comptant plus de 200 membres appartenant à quinze institutions académiques. La mission de l’ACCFC-CITAC est d’organiser et de promouvoir des activités qui soutiennent les cliniciens-chercheurs en formation au Canada, dans l’intention d’améliorer les opportunités de carrières académiques et post-graduées, d’augmenter la visibilité institutionnelle et publique des programmes cliniciens-chercheurs et de développer une base de donnée accessible à l’échelle nationale, des étudiants et des programmes en développement. L’ACCFC-CITAC vise également à améliorer les conditions des cliniciens-chercheurs en début de carrière, dans le but d’élargir et de faire progresser les initiatives de recherche novatrices à l’intérieur du Canada. Au cours de son développement, l’ACCFC-CITAC a pu compter sur le mentorat et les conseils de la Société canadienne de recherche clinique (SCRC). Les relations en pleine croissance entre l’ACCFC-CITAC et la SCRC ont permis, à travers une nouvelle collaboration, la création d’une opportunité innovatrice pour les cliniciens-chercheurs en formation, soit la mise sur pied d’une section dédiée (Section étudiante) dans le journal officiel de la SCRC, le « Clinical and Investigative Medicine (CIM) Journal ».
En tant que forum par lequel des travaux portant sur divers sujets seront partagés, la Section étudiante du CIM constituera une belle opportunité en rapport au développement professionnel. Les étudiants en formation au sein des programmes MD+ représentent la prochaine génération de cliniciens-chercheurs qui seront appelés à intégrer la recherche dans des domaines de pointe au sein de leur pratique ainsi que dans les soins aux patients. Ces deux professions exigent d’excellentes habiletés de communication et c’est donc par le biais de la Section étudiante du CIM que les étudiants MD+, leurs superviseurs ainsi que les responsables de programmes MD+ seront en mesure de mettre en valeur des sujets touchant les étudiants MD+ tels que le mentorat, l’enseignement académique, la planification financière et le développement professionnel. En plus d’articles soulignant les activités de recherche des étudiants, la Section étudiante mettra en valeur des travaux cliniques, des articles de synthèse, des résumés de thèses, des comptes-rendus de livres ainsi que des lettres d’opinion. L’orientation de cette section complémentera l’orientation actuelle de la revue CIM qui met à l’avant-plan les articles originaux et les sujets d’intérêts à la SCRC. Il est donc tout à fait pertinent de mettre en place une Section étudiante dédiée à des sujets qui émergent rapidement au cours de la formation d’un clinicien-chercheur. Étant donné que les programmes MD+ se répandent à travers le monde, la Section étudiante favorisera la mise en place d’un forum international encadrant la formation des MD+. En augmentant la portée internationale de la revue CIM par le biais du site web de l’ACCFC-CITAC, nous souhaitons inciter les étudiants MD+, les responsables des programmes, les instances universitaires et autres leaders de l’éducation à s’impliquer et prendre position sur des questions importantes sur le plan national et international.
Comme les cliniciens-chercheurs en formation seront responsables de surveiller le processus d’édition et de révision par les pairs de la Section étudiante, nous prévoyons que cela ouvre la voie vers la consolidation des collaborations entre les cliniciens-chercheurs en formation sur notre comité de rédaction, les chercheurs juniors et les professeurs séniors, tout en apportant une expérience éditoriale critique aux membres du comité. Notre équipe d’éditeurs s’assurera que les articles soient révisés de façon équitable et convenable, en respectant la nécessité de publier rapidement les articles de pertinence immédiate. Nous encourageons tous les MD+ en formation à participer au processus d’édition et/ou de révision par les pairs. Des détails additionnels sont disponibles sur notre site internet à l’adresse suivante:
http://www.citac-accfc.org/portal/
En tant qu’étudiants MD+, nous sommes optimistes quant à l’avenir des sciences fondamentales et de la recherche clinique. Les temps actuels sont stimulants pour les étudiants MD+ et nous avons bon espoir que la création de la Section étudiante promouvra de surcroît cette expérience. Nous vous encourageons fortement à publier vos travaux de recherche dans la Section étudiante et ainsi prendre part à une communauté émergente d’étudiants MD+ intéressés par les enjeux du domaine de la santé qui nous affectent, peu importe notre lieu géographique, notre culture ou notre origine.
Nous attendons donc vos articles.
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Ong Tone S, Dugani S, Marshall H, Shamji MF, Murray JC, Bossé D. Scientific overview of the CSCI-CITAC 2009 conference. CLIN INVEST MED 2010; 33:E69-72, E73-7. [PMID: 20144273 DOI: 10.25011/cim.v33i1.11840] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2010] [Indexed: 11/03/2022]
Abstract
From September 21st-23rd 2009, the Clinical Investigator Trainee Association of Canada - Association des cliniciens-chercheurs en formation du Canada (CITAC-ACCFC) and the Canadian Society for Clinician Investigators (CSCI), held their annual conference in Ottawa. Participants included clinician investigators and trainees from across the country. The conference featured many excellent guest speakers including this year's recipient of the Henry G. Friesen International Prize in Health Research, Sir John Bell. There were several forums focusing on professional development, with topics such as "sustaining the clinician investigator in Canada", "succeeding as a clinician investigator", and "collaborating internationally with MD+ trainees", alongside networking opportunities to help establish relationships with potential mentors and collaborators. Further, the CSCI-CITAC annual conference featured some of the cutting edge research that MD+ trainees throughout Canada are engaged in. Trainees presented their research either at the Young Investigators Forum poster session or at the oral plenary. This scientific overview aims to highlight some of the research presented by trainees at the annual conference. The broad themes of scientific interest included topics from both basic science and clinical research. In this article, we summarize some of the major research questions that are being investigated by clinician-investigator trainees in the following areas: neurological sciences, cell biology, medicine, immunology, obstetrics, gynecology, neonatology, orthopedics, rheumatology, and public health.
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Affiliation(s)
- Stephan Ong Tone
- Department of Neurology and Neurosurgery, Montreal Neurological Institute, 3801 Rue University, Montreal, Quebec H3A 2B4.
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Tone SO, Alabed YZ, Fournier AE. The role of CRMP4 in nerve regenerations. CLIN INVEST MED 2007. [DOI: 10.25011/cim.v30i4.2869] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
The inability of CNS neurons to regenerate and reform functional connections following spinal cord injury has devastating clinical consequences. The failure of CNS neurons to spontaneously regenerate following injury can be partially attributed to the expression of neurite outgrowth inhibitory myelin associated inhibitors (MAIs). MAIs signal through a tripartite receptor complex to activate the cytosolic protein RhoA and influence cytoskeletal dynamics. RhoA antagonists promote neuronal survival and regeneration in animal models of nerve injury. However, RhoA's potential as a therapeutic target may be limited by its widespread roles in multiples cellular processes and cell types. In an attempt to discover more specific therapeutic targets to promote nerve regeneration, our lab identified the cytosolic phosphoprotein CRMP4b (Collapsin Response Mediator Protein 4b) as a protein that functionally interacts with RhoA to mediate neurite outgrowth inhibition. siRNA-mediated knockdown of CRMP4 and blockade of the RhoA-CRMP4b interaction with a competitive peptide (C4RIP) attenuates myelin-dependent neurite outgrowth inhibition. Analysis of the proximal tip of extending axons (growth cones) by time lapse video microscopy reveals that C4RIP regulates filopodial dynamics indicating that C4RIP modulates the actin cytoskeleton. We are currently investigating the in vivo roles of CRMP4 in regeneration in an optic nerve injury model by developing readily deliverable C4RIP and a CRMP4 knockout mouse. Elucidating the role of CRMP4 in nerve regeneration may provide insight into the molecular mechanisms following nervous system injury.
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Abstract
Myelin-associated inhibitors (MAIs) and chondroitin sulfate proteoglycans (CSPGs) contribute to failed regeneration after neuronal injury. MAIs and CSPGs stimulate intracellular signals including the activation of RhoA and Rho kinase to block axonal extension through targeted modifications to the cytoskeleton. RhoA and ROCK are promising targets for therapeutic intervention to promote CNS repair; however, their ubiquitous expression will limit the specificity of drugs targeted to these molecules. We have identified the cytosolic phosphoprotein CRMP4b (collapsin-response mediator protein 4b) as a protein that physically and functionally interacts with RhoA to mediate neurite outgrowth inhibition. Short interfering RNA-mediated knockdown of CRMP4 promotes neurite outgrowth on myelin substrates, indicating a critical role for CRMP4 in neurite outgrowth inhibition. Disruption of CRMP4b-RhoA binding with a competitive inhibitor attenuates neurite outgrowth inhibition on myelin and aggrecan substrates. Stimulation of neuronal growth cones with Nogo leads to colocalization of CRMP4b and RhoA at discrete regions within the actin-rich central and peripheral domains of the growth cone, indicative of a potential function in cytoskeletal rearrangements during neurite outgrowth inhibition. Together, these data indicate that a RhoA-CRMP4b complex forms in response to inhibitory challenges in the growth cone environment and regulates cytoskeletal dynamics at distinct sites necessary for axon outgrowth inhibition. Competitive inhibition of CRMP4b-RhoA binding suggests a novel, highly specific therapeutic avenue for promoting regeneration after CNS injury.
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Affiliation(s)
- Yazan Z. Alabed
- Department of Neurology and Neurosurgery, Montreal Neurological Institute, Montreal, Quebec, Canada H3A 2B4
| | - Madeline Pool
- Department of Neurology and Neurosurgery, Montreal Neurological Institute, Montreal, Quebec, Canada H3A 2B4
| | - Stephan Ong Tone
- Department of Neurology and Neurosurgery, Montreal Neurological Institute, Montreal, Quebec, Canada H3A 2B4
| | - Alyson E. Fournier
- Department of Neurology and Neurosurgery, Montreal Neurological Institute, Montreal, Quebec, Canada H3A 2B4
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