Publications by authors named "Thomas Chuen Lam"

Age-related macular degeneration (AMD) is a degenerative eye disease leading to central vision loss and is characterized by dysregulated autophagy of the retinal pigment epithelium (RPE) layer. Recent studies have suggested that rho-associated protein kinase (ROCK) inhibitors may enhance autophagy in neurodegenerative diseases and promote the survival of RPE cells. This study investigated the effect of ROCK inhibitors on autophagy gene expression and autophagic vacuole formation in a human RPE (ARPE-19) cell line.

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Aim: To investigate the proliferation regulatory effect of cone-rod homeobox (CRX) in retinal pigment epithelium (RPE) and retinoblastoma (RB) cells to explore the potential application and side effect (oncogenic potential) of CRX-based gene therapy in RPE-based retinopathies.

Methods: Adult human retinal pigment epithelial (ARPE)-19 and human retinal pigment epithelial (RPE)-1 cells and Y79 RB cell were used in the study. Genetic manipulation was performed by lentivirus-based technology.

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The vitreous humor (VH) is a transparent gelatin-like substance that occupies two-thirds of the eyeball and undergoes the most significant changes during eye elongation. Quantitative proteomics on the normal growth period in the VH could provide new insights into understanding its progression mechanism in the early stages of myopia. In this study, a data-independent acquisition (SWATH-MS) was combined with targeted LC-ESI-MS/MS to identify and quantify the relative protein changes in the vitreous during the normal growth period (4, 7, 14, 21 and 28 days old) in the chick model.

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Aims: The relationship between retinal electrophysiological function and myopia progression was evaluated in school-aged children wearing Breath-O-Correct Orthokeratology (OK) lenses compared with those wearing single vision (SV) lenses over 24 months.

Methods: In this randomised, single-blind, parallel controlled trial, children aged 8-12 years with -1.00 to -4.

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Introduction: Multifactorial Eye disorders are a significant public health concern and have a huge impact on quality of life. The pathophysiological mechanisms underlying these eye disorders were not completely understood since functional and low-throughput biological tests were used. By identifying biomarkers linked to eye disorders, metabolomics enables early identification, tracking of the course of the disease, and personalized treatment.

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Purpose: To investigate the tear proteomic and neuromediator profiles, in vivo confocal microscopy (IVCM) imaging features, and clinical manifestations in neuropathic corneal pain (NCP) patients.

Design: Cross-sectional study.

Methods: A total of 20 NCP patients and 20 age-matched controls were recruited.

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Tear fluid is one of the easily accessible biofluids that can be collected non-invasively. Tear proteomics has the potential to discover biomarkers for several ocular diseases and conditions. The suspension trapping column has been reported to be an efficient and user-friendly sample preparation workflow for the broad application of downstream proteomic analysis.

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Traditional Chinese Medicine has a long history in ophthalmology in China. Over 250 kinds of Traditional Chinese Medicine have been recorded in ancient books for the management of eye diseases, which may provide an alternative or supplement to current ocular therapies. However, the core holistic philosophy of Traditional Chinese Medicine that makes it attractive can also hinder its understanding from a scientific perspective - in particular, determining true cause and effect.

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To explore the temporal profile of retinal proteomes specific to primary and secondary retinal ganglion cell (RGC) loss. Unilateral partial optic nerve transection (pONT) was performed on the temporal side of the rat optic nerve. Temporal and nasal retinal samples were collected at 1, 4 and 8 weeks after pONT (n = 4 each) for non-biased profiling with a high-resolution hybrid quadrupole time-of-flight mass spectrometry running on label-free SWATH acquisition (SCIEX).

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Background: In the past decade and during the COVID pandemic, the prevalence of myopia has reached epidemic proportions. To address this issue and reduce the prevalence of myopia and its complications, it is necessary to develop more effective interventions for controlling myopia. In this study, we investigated the combined effects of narrowband lights and competing defocus on eye growth and refraction in chicks, an important step in understanding the potential for these interventions to control myopia.

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Diabetic retinopathy (DR) was identified as a leading cause of blindness and vision impairment in 2020. In addition to vasculopathy, DR has been found to involve retinal neurons, including amacrine cells and retinal ganglion cells. Despite possessing features that are susceptible to diabetic conditions, photoreceptor cells have received relatively little attention with respect to the development of DR.

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Elevated intraocular pressure (IOP) is a major risk factor for glaucoma that results from impeded fluid drainage. The increase in outflow resistance is caused by trabecular meshwork (TM) cell dysfunction and excessive extracellular matrix (ECM) deposition. Baicalein (Ba) is a natural flavonoid and has been shown to regulate cell contraction, fluid secretion, and ECM remodeling in various cell types, suggesting the potential significance of regulating outflow resistance and IOP.

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Uveitis is a group of sight-threatening ocular inflammatory diseases, potentially leading to permanent vision loss in patients. However, it remains largely unknown how uveitis causes retinal malfunction and vision loss. Endotoxin-induced uveitis (EIU) in rodents is a good animal model to study uveitis and associated acute retinal inflammation.

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Gene expression of the chick retina was examined during the early development of lens-induced myopia (LIM) using whole transcriptome sequencing. Monocular treatment of the right eyes with -10 diopter (D) lenses was performed on newly born chicks for one day (LIM-24) or two days (LIM-48), while the contralateral eyes without lenses served as controls. Myopia development was confirmed by demonstrating significant elongation of the optical axis in lens-treated eyes compared to untreated control eyes.

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Atropine, a non-selective muscarinic antagonist, effectively slows down myopia progression in human adolescents and several animal models. However, the underlying molecular mechanism is unclear. The current study investigated retinal protein changes of form-deprived myopic (FDM) guinea pigs in response to topical administration of 1% atropine gel (10 g/L).

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Rho-kinase (ROCK) inhibitors, a novel class of anti-glaucoma agents, act by increasing the aqueous humor outflow through the conventional trabecular meshwork pathway. However, the downstream signaling consequences of the ROCK inhibitor are not completely understood. Our data show that Y39983, a selective ROCK inhibitor, could induce filamentous actin remodeling, reduced cell motility (as measured by cell migration), and transepithelial resistance in primary human TM (hTM) cells.

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Water Gradient Contact Lens (WGCL) is a new generation material that combines the benefits of Silicone hydrogel (SiHy) and traditional hydrogel contact lenses by modifying the materials between the core and the surface. However, its impact on tear proteome has not been explored. Tears were collected on healthy young adults using Schirmer's strip at baseline, 1-week, and 1-month of WGCL lens wear (=15) and age-matched untouched controls (=10).

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Low-dose atropine helps to control myopia progression with few side effects. However, the impact of atropine, a non-selective muscarinic Acetylcholine (ACh) receptor antagonist, on retinal ganglion cells (RGCs) remains unclear. After immersing the cornea and adjacent conjunctiva of enucleated eyes in 0.

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Most of the previous myopic animal studies employed a single-candidate approach and lower resolution proteomics approaches that were difficult to detect minor changes, and generated limited systems-wide biological information. Hence, a complete picture of molecular events in the retina involving myopic development is lacking. Here, to investigate comprehensive retinal protein alternations and underlying molecular events in the early myopic stage, we performed a data-independent Sequential Window Acquisition of all Theoretical Mass Spectra (SWATH) based proteomic analysis coupled with different bioinformatics tools in pigmented guinea pigs after 4-day lens-induced myopia (LIM).

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The tear film is a layer of body fluid that maintains the homeostasis of the ocular surface. The superior accessibility of tears and the presence of a high concentration of functional proteins make tears a potential medium for the discovery of non‑invasive biomarkers in ocular diseases. Recent advances in mass spectrometry (MS) have enabled determination of an in‑depth proteome profile, improved sensitivity, faster acquisition speed, proven variety of acquisition methods, and identification of disease biomarkers previously lacking in the field of ophthalmology.

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Myopia, or short-sightedness, is a highly prevalent refractive disorder in which the eye's focal length is too short for its axial dimension in its relaxed state. High myopia is associated with increased risks of blinding ocular complications and abnormal eye shape. In addition to consistent findings on posterior segment anomalies in high myopia (e.

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The retina is a key sensory tissue composed of multiple layers of cell populations that work coherently to process and decode visual information. Mass spectrometry-based proteomics approach has allowed high-throughput, untargeted protein identification, demonstrating the presence of these proteins in the retina and their involvement in biological signalling cascades. The comprehensive wild-type mouse retina proteome was prepared using a novel sample preparation approach, the suspension trapping (S-Trap) filter, and further fractionated with high-pH reversed phase chromatography involving a total of 28 injections.

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Atropine, a non-selective muscarinic antagonist, is known to slow down myopia progression in human adolescents and in several animal models. However, its underlying molecular mechanism is unclear. The present work built a monocular form-deprivation myopia (FDM) guinea pig model, using facemasks as well as atropine treatment on FDM eyes for 2 and 4 weeks.

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Rho-associated coiled coil-forming protein kinase (ROCK) inhibitors represent a novel class of anti-glaucoma drugs because of their ocular hypotensive effects. However, the underlying mechanisms responsible for lowering intraocular pressure (IOP) are not completely clear. The protein profile changes in primary human trabecular meshwork (TM) cells after two days treatment with a ROCK inhibitor were studied using label-free SWATH acquisition.

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Myopia is the most common refractive error which is estimated to affect half the population of the world by 2050. It has been suggested that it could be determined by multiple factors such as environmental and genetic, but the mechanism behind the cause of myopia is still yet to be identified. Vitreous humor (VH) is a transparent gelatin-like substance that takes up to 80% of the volume of the eye, making it the largest component of the eye.

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