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Fulltext NADPH Oxidase versus Mitochondria-Derived ROS in Glucose-Induced Apoptosis of Pericytes in Early Diabetic Retinopathy

Mustapha NM, Tarr JM, Kohner EM, Chibber R

J Ophthalmol, 2010;2010:746978.
PMID: 20652059 DOI: 10.1155/2010/746978

Objectives. Using apocynin (inhibitor of NADPH oxidase), and Mitoquinol 10 nitrate (MitoQ; mitochondrial-targeted antioxidant), we addressed the importance of mitochondria versus NADPH oxidase-derived ROS in glucose-induced apoptosis of pericytes. Methods. NADPH oxidase was localised using Western blot analysis and cytochrome C reduction assay. Apoptosis was detected by measuring caspase-3 activity. Intracellular glucose concentration, ROS formation and Nepsilon-(carboxymethyl) lysine (CML) content were measured using Amplex Red assay kit, dihydroethidium (DHE), and competitive immunoabsorbant enzyme-linked assay (ELISA), respectively. Results. NADPH oxidase was localised in the cytoplasm of pericytes suggesting ROS production within intracellular compartments. High glucose (25 mM) significantly increased apoptosis, intracellular glucose concentration, and CML content. Apoptosis was associated with increased gp91phox expression, activity of NADPH oxidase, and intracellular ROS production. Apocynin and not MitoQ significantly blunted the generation of ROS, formation of intracellular CML and apoptosis. Conclusions. NADPH oxidase and not mitochondria-derived ROS is responsible for the accelerated apoptosis of pericytes in diabetic retinopathy.
Fulltext Evaluation of Retinal Nerve Fiber Layer Thickness, Electroretinogram and Visual Evoked Potential in Patients with Alzheimer's Disease

Ngoo QZ, Wan Hitam WH, Ab Razak A

J Ophthalmol, 2019;2019:6248185.
PMID: 31949951 DOI: 10.1155/2019/6248185

OBJECTIVE: To study the retinal nerve fibre layer (RNFL) thickness and visual electrophysiology testing in patients with Alzheimer's disease (AD).
METHODS: A cross-sectional, hospital-based study: 25 AD subjects and 25 controls were recruited. Candidates who fulfil the criteria with normal ocular examinations were made to proceed with scanning laser polarimetry, pattern electroretinogram (PERG), and pattern visual evoked potential (PVEP) examinations of the right eye. RNFL thickness, PERG, and PVEP readings were evaluated.
RESULTS: In AD, the mean of average RNFL thickness was 45.28 μm, SD = 3.61, P < 0.001 (P < 0.05), while the superior RNFL thickness was 54.44 μm, SD = 2.85, P < 0.001 (P < 0.05) and inferior RNFL thickness was 47.11 μm, SD = 4.52, P < 0.001 (P < 0.05). For PERG, the mean P50 latency was 63.88 ms, SD = 7.94, P < 0.001 (P < 0.05) and the mean amplitudes of P50 waves were 1.79 μV, SD = 0.64, P < 0.001 (P < 0.05) and N95 waves were 2.43 μV, SD = 0.90, P < 0.001 (P < 0.05). For PVEP, the mean latency of P100 was 119.00 ms, SD = 9.07, P < 0.001 (P < 0.05), while the mean latency of N135 was 145.20 ms, SD = 8.53, P < 0.001 (P < 0.05). The mean amplitude of P100 waves was 3.71 μV, SD = 1.60, P < 0.001 (P < 0.05), whereas the mean amplitude of N135 waves was 3.67 μV, SD = 2.02, P < 0.001 (P < 0.05). RNFL thickness strongly correlates with PERG readings, with P50 latency R = 0.582, R2 = 0.339, P=0.002 (P < 0.05), amplitude of P50 wave at R = 0.749, R2 = 0.561, P ≤ 0.001 (P < 0.05), and amplitude of N95 wave at R = 0.500, R2 = 0.250, P=0.011 (P < 0.05). No significant difference and correlation were observed on PVEP readings.
CONCLUSION: The mean of the average, superior and inferior RNFL thickness were significantly lower in the AD group compared with control. There is also significant difference of PERG and PVEP parameters between AD and controls. Regression analysis showed average RNFL thickness having significantly linear relationship with the PERG parameters.
Fulltext Classification of SD-OCT Volumes Using Local Binary Patterns: Experimental Validation for DME Detection

Lemaître G, Rastgoo M, Massich J, Cheung CY, Wong TY, Lamoureux E, et al.

J Ophthalmol, 2016;2016:3298606.
PMID: 27555965 DOI: 10.1155/2016/3298606

This paper addresses the problem of automatic classification of Spectral Domain OCT (SD-OCT) data for automatic identification of patients with DME versus normal subjects. Optical Coherence Tomography (OCT) has been a valuable diagnostic tool for DME, which is among the most common causes of irreversible vision loss in individuals with diabetes. Here, a classification framework with five distinctive steps is proposed and we present an extensive study of each step. Our method considers combination of various preprocessing steps in conjunction with Local Binary Patterns (LBP) features and different mapping strategies. Using linear and nonlinear classifiers, we tested the developed framework on a balanced cohort of 32 patients. Experimental results show that the proposed method outperforms the previous studies by achieving a Sensitivity (SE) and a Specificity (SP) of 81.2% and 93.7%, respectively. Our study concludes that the 3D features and high-level representation of 2D features using patches achieve the best results. However, the effects of preprocessing are inconsistent with different classifiers and feature configurations.
Fulltext Association between Ocular Pseudoexfoliation and Sensorineural Hearing Loss

Singham NV, Zahari M, Peyman M, Prepageran N, Subrayan V

J Ophthalmol, 2014;2014:825936.
PMID: 24864196 DOI: 10.1155/2014/825936

Background. Our study aimed to investigate an association between ocular pseudoexfoliation (PXF) and sensorineural hearing loss (SNHL) and to compare them with age and sex matched controls without pseudoexfoliation. Method. This was a case-control study of 123 patients which included 68 cases with PXF (at least one eye) and 55 controls without pseudoexfoliation. Pure-tone audiometry (PTA) was done for these patients at sound frequencies taken as important for speech comprehension, that is, 250 Hertz (Hz), 500 Hz, 1000 Hz, and 2000 Hz. Results. There were 41 patients with pseudoexfoliation syndrome (PXE) and 27 with pseudoexfoliative glaucoma (PXEG). The majority of patients with hearing loss (60%; n = 51) were PXF patients and the remaining 40% (n = 34) were controls. Below average hearing thresholds were significantly higher in the pseudoexfoliation group compared to the control group (P = 0.01; odds ratio (OR), 3.00; 95% confidence interval (CI), 1.25-7.19). However, there was no significant difference in the mean hearing threshold levels between the three groups (PXE, PXEG, and controls) in either ear (ANOVA, right ear: P = 0.46 and left ear P = 0.36). Conclusion. Our study found an association between PXF and SNHL, confirming that PXF can involve organs in the body other than the eye.
Fulltext Current Advances in Pharmacotherapy and Technology for Diabetic Retinopathy: A Systematic Review

Lu L, Jiang Y, Jaganathan R, Hao Y

J Ophthalmol, 2018;2018:1694187.
PMID: 29576875 DOI: 10.1155/2018/1694187

Diabetic retinopathy (DR) is classically defined by its vascular lesions and damage in the neurons of the retina. The cellular and clinical elements of DR have many features of chronic inflammation. Understanding the individual cell-specific inflammatory changes in the retina may lead to novel therapeutic approaches to prevent vision loss. The systematic use of available pharmacotherapy has been reported as a useful adjunct tool to laser photocoagulation, a gold standard therapy for DR. Direct injections or intravitreal anti-inflammatory and antiangiogenesis agents are widely used pharmacotherapy to effectively treat DR and diabetic macular edema (DME). However, their effectiveness is short term, and the delivery system is often associated with adverse effects, such as cataract and increased intraocular pressure. Further, systemic agents (particularly hypoglycemic, hypolipidemic, and antihypertensive agents) and plants-based drugs have also provided promising treatment in the progression of DR. Recently, advancements in pluripotent stem cells technology enable restoration of retinal functionalities after transplantation of these cells into animals with retinal degeneration. This review paper summarizes the developments in the current and potential pharmacotherapy and therapeutic technology of DR. Literature search was done on online databases, PubMed, Google Scholar, clinitrials.gov, and browsing through individual ophthalmology journals and leading pharmaceutical company websites.
Fulltext Corrigendum to "Current Advances in Pharmacotherapy and Technology for Diabetic Retinopathy: A Systematic Review"

Lu L, Jiang Y, Jaganathan R, Hao Y

J Ophthalmol, 2018;2018:5047142.
PMID: 30622819 DOI: 10.1155/2018/5047142

[This corrects the article DOI: 10.1155/2018/1694187.].
Fulltext Prevalence and Factors Associated with Self-Reported Vision Disability among the Elderly in Malaysia: Findings from National Health and Morbidity Survey (NHMS) 2018

Rezali MS, Ab Wahab NA, Sahril N, Ramli MHT, Shahein NA, Chan YY, et al.

J Ophthalmol, 2021;2021:7564827.
PMID: 34007483 DOI: 10.1155/2021/7564827

Introduction: Disability has adverse effects on health, wellbeing, and life quality. Vision disorder is one of the top-ranked causes of disability in the elderly population. This study aims to determine the prevalence and factors associated with vision disability among the elderly in Malaysia. Methodology. Data collection from National Health and Morbidity Survey (NHMS) 2018 was obtained. This survey focused on elderly health by using two-stage stratified cluster sampling design. The Washington Group Extended Question Set on Functioning (WG ES-F) was used to determine the vision disability. The data were analyzed using SPSS version 21.0 utilizing a complex sample design with multivariable logistic regression analysis to determine the prevalence and associated factors to vision disability.
Results: A total of 3,977 elderly completed the vision disability questionnaire. The overall prevalence of vision disability among those who were 60 years old and above was 4.5%. Multiple logistic regression revealed that no formal education (AOR: 6.69, 95% CI: 1.52, 29.49), only primary education (AOR: 4.26, 95% CI: 1.01, 18.03), unemployed/retiree or homemaker (AOR: 3.25, 95% CI: 1.79, 5.89), hypertension (AOR: 1.45, 95% CI: 1.00, 2.09), and malnourished elderly (AOR: 2.84, 95% CI: 1.76, 461) had higher odds for having vision disability.
Conclusion: The findings suggest that a low education level, unemployment, hypertension, and malnourishment are significant risk factors for VD among Malaysia's elderly. Strengthening awareness campaigns to increase VD awareness and provide high-quality rehabilitation services must target specific groups, such as the elderly with a low level of education and the unemployed. Empower primary healthcare providers with the knowledge and skills necessary to improve the quality of eye care delivery and expand eye screening in settling VD issues nationally.