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1.
Langmuir ; 40(35): 18486-18502, 2024 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-39172065

RESUMO

Carbon-based nanostructures are promising eco-friendly multifunctional nanomaterials because of their tunable surface and optoelectronic properties for a variety of energy and environmental applications. The present study focuses on the synthesis of graphene oxide (GO) with particular emphasis on engineering its surface and optical properties for making it an excellent adsorbent as well as a visible light-active photocatalyst. It was achieved by modifying the improved Hummers method through optimizing the synthesis parameters involved in the oxidation process. This controlled synthesis allows for systematic tailoring of structural, optical, and surface functionality, leading to improved adsorption and photocatalytic properties for the sustainable removal of organic pollutants in water treatment. Several spectroscopic and microscopic characterization techniques, such as XRD, SEM, Raman, UV-visible, FTIR, TEM, XPS, BET, etc. were employed to analyze the degree of oxidation, surface chemistry/functionalization, morphological, optical, and structural properties of the synthesized GO nanostructures. The analyses showed excellent surface functionality with surface active sites for better adsorptive removal and a tunable band gap from 2.51 to 2.76 eV exhibiting excellent natural sunlight activity (>99%) for photocatalytic removal of the organic pollutant. Various adsorption isotherms have been studied with excellent adsorption capability (Qmax = 454.54 mg/g) as compared to the literature. The study introduces GO both as a proficient stand-alone (sole) nanoadsorbent as well as a nanophotocatalyst for the efficient removal of organic dye pollutants in water treatment. Additionally, the article highlights the sustainable solar light-induced green chemistry aspects of GO as an excellent recyclable adsorbent as a result of its self-cleaning ability under natural sunlight, demonstrating its potential in real eco-friendly environmental and practical applications.

2.
BMC Med ; 21(1): 28, 2023 01 24.
Artigo em Inglês | MEDLINE | ID: mdl-36691041

RESUMO

BACKGROUND: Currently in the United Kingdom, cardiovascular disease (CVD) risk assessment is based on the QRISK3 score, in which 10% 10-year CVD risk indicates clinical intervention. However, this benchmark has limited efficacy in clinical practice and the need for a more simple, non-invasive risk stratification tool is necessary. Retinal photography is becoming increasingly acceptable as a non-invasive imaging tool for CVD. Previously, we developed a novel CVD risk stratification system based on retinal photographs predicting future CVD risk. This study aims to further validate our biomarker, Reti-CVD, (1) to detect risk group of ≥ 10% in 10-year CVD risk and (2) enhance risk assessment in individuals with QRISK3 of 7.5-10% (termed as borderline-QRISK3 group) using the UK Biobank. METHODS: Reti-CVD scores were calculated and stratified into three risk groups based on optimized cut-off values from the UK Biobank. We used Cox proportional-hazards models to evaluate the ability of Reti-CVD to predict CVD events in the general population. C-statistics was used to assess the prognostic value of adding Reti-CVD to QRISK3 in borderline-QRISK3 group and three vulnerable subgroups. RESULTS: Among 48,260 participants with no history of CVD, 6.3% had CVD events during the 11-year follow-up. Reti-CVD was associated with an increased risk of CVD (adjusted hazard ratio [HR] 1.41; 95% confidence interval [CI], 1.30-1.52) with a 13.1% (95% CI, 11.7-14.6%) 10-year CVD risk in Reti-CVD-high-risk group. The 10-year CVD risk of the borderline-QRISK3 group was greater than 10% in Reti-CVD-high-risk group (11.5% in non-statin cohort [n = 45,473], 11.5% in stage 1 hypertension cohort [n = 11,966], and 14.2% in middle-aged cohort [n = 38,941]). C statistics increased by 0.014 (0.010-0.017) in non-statin cohort, 0.013 (0.007-0.019) in stage 1 hypertension cohort, and 0.023 (0.018-0.029) in middle-aged cohort for CVD event prediction after adding Reti-CVD to QRISK3. CONCLUSIONS: Reti-CVD has the potential to identify individuals with ≥ 10% 10-year CVD risk who are likely to benefit from earlier preventative CVD interventions. For borderline-QRISK3 individuals with 10-year CVD risk between 7.5 and 10%, Reti-CVD could be used as a risk enhancer tool to help improve discernment accuracy, especially in adult groups that may be pre-disposed to CVD.


Assuntos
Doenças Cardiovasculares , Aprendizado Profundo , Hipertensão , Adulto , Pessoa de Meia-Idade , Humanos , Doenças Cardiovasculares/epidemiologia , Bancos de Espécimes Biológicos , Fatores de Risco , Reino Unido/epidemiologia , Hipertensão/complicações , Biomarcadores
3.
Analyst ; 148(11): 2582-2593, 2023 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-37159231

RESUMO

Diethyl cyanophosphonate (DCNP), a simulant of Tabun, is a common pollutant in pharmaceutical waste and poses a high risk to living organisms. Herein, we demonstrate a compartmental ligand-derived trinuclear zinc(II) cluster [Zn3(LH)2(CH3COO)2] as a probe for the selective detection and degradation of DCNP. It consists of two pentacoordinated Zn(II) [4.4.3.01,5]tridecane cages bridged through a hexacoordinated Zn(II) acetate unit. The structure of the cluster has been elucidated by spectrometric, spectroscopic, and single-crystal X-ray diffraction studies. The cluster shows a two-fold increased emission as compared to the compartmental ligand (at λexc = 370 nm and λem = 463 nm) due to the chelation-enhanced fluorescence effect and acts as a turn-off signal in the presence of DCNP. It can detect DCNP at nano levels up to 186 nM (LOD). The direct bond formation between DCNP and Zn(II) via the -CN group degrades it to inorganic phosphates. The mechanism of the interaction and degradation is supported by spectrofluorimetric experiments, NMR titration (1H and 31P), time of flight mass spectrometry and density functional theory calculations. The applicability of the probe has been further tested by the bio-imaging of zebrafish larvae, analysis of high-protein food products (meat and fish) and vapour phase detection by paper strips.


Assuntos
Substâncias para a Guerra Química , Animais , Substâncias para a Guerra Química/análise , Zinco/análise , Peixe-Zebra , Ligantes , Preparações Farmacêuticas
4.
BMC Ophthalmol ; 23(1): 287, 2023 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-37353735

RESUMO

BACKGROUND: To assess the anxiety and depression levels in patients with Posner-Schlossman syndrome (PSS) and to determine the potential risk factors. METHODS: In this cross-sectional study, a total of 195 participants, including 93 PSS patients and 102 healthy controls were recruited. Sociodemographic and clinical information were collected for all participants. Hospital Anxiety and Depression scale (HADS) was administered to evaluate the anxiety and depression levels. Visual function (VF) and quality-of-life (QOL) questionnaires were administered to assess variables potentially associated with anxiety and depression. RESULTS: Increased anxiety level was observed in 22 (23.7%) PSS patients as compared to 10 (9.8%) of controls (P = 0.009). While the frequency of depression between the two groups was not significantly different (P = 0.349). The mean anxiety and depression scores were 6.98 ± 4.20 and 6.44 ± 3.66 in PSS patients as compared to 6.67 ± 3.21 (P = 0.564) and 5.96 ± 2.93 (P = 0.311) in controls. Logistic regression analysis showed mental well-being was significantly associated with anxiety (odds ratio [OR] = 0.920, 95% confidence interval [CI] = 0.881-0.962, P < 0.001) and depression (OR = 0.959, CI = 0.926-0.994, P = 0.023) in PSS patients. CONCLUSION: More patients with PSS may experience anxiety as compared to healthy controls. Mental well-being is an independent risk factor for anxiety and depression. It is important for ophthalmologists to be aware of these factors and should pay more attention on mental health when PSS is managed in clinic.


Assuntos
Depressão , Qualidade de Vida , Humanos , Depressão/diagnóstico , Depressão/etiologia , Estudos Transversais , Ansiedade/diagnóstico , Ansiedade/psicologia , Transtornos de Ansiedade/diagnóstico
5.
Ophthalmology ; 129(3): 285-294, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34592243

RESUMO

PURPOSE: We hypothesized that the effect of blood lipid-related metabolites on primary open-angle glaucoma (POAG) would differ according to specific lipoprotein particles and lipid sub-fractions. We investigated the associations of blood levels of lipoprotein particles and lipid sub-fractions with POAG. DESIGN: Cross-sectional study. PARTICIPANTS: Individuals recruited for the baseline visit of the population-based Singapore Epidemiology of Eye Disease study (n = 8503). METHODS: All participants underwent detailed standardized ocular and systemic examinations. A total of 130 blood lipid-related metabolites were quantified using a nuclear magnetic resonance metabolomics platform. The analyses were conducted in 2 stages. First, we investigated whether and which lipid-related metabolites were directly associated with POAG using regression analyses followed by Bayesian network modeling. Second, we investigated if any causal relationship exists between the identified lipid-related metabolites, if any, and POAG using 2-sample Mendelian randomization (MR) analysis. We performed genome-wide association studies (GWAS) on high-density lipoprotein (HDL) 3 cholesterol (after inverse normal transformation) and used the top variants associated with HLD3 cholesterol as instrumental variables (IVs) in the MR analysis. MAIN OUTCOME MEASURE: Primary open-angle glaucoma. RESULTS: Of the participants, 175 (2.1%) had POAG. First, a logistic regression model showed that total HDL3 cholesterol (negatively) and phospholipids in very large HDL (positively) were associated with POAG. Further analyses using a Bayesian network analysis showed that only total HDL3 cholesterol was directly associated with POAG (odds ratio [OR], 0.72 per 1 standard deviation increase in HDL3 cholesterol; 95% confidence interval [CI], 0.61-0.84), independently of age, gender, intraocular pressure (IOP), body mass index (BMI), education level, systolic blood pressure, axial length, and statin medication. Using 5 IVs identified from the GWAS and with the inverse variance weighted MR method, we found that higher levels of HDL3 cholesterol were associated with a decreased odds of POAG (OR, 0.91; 95% CI, 0.84-0.99, P = 0.021). Other MR methods, including weighted median, mode-based estimator, and contamination mixture methods, derived consistent OR estimates. None of the routine lipids (blood total, HDL, or low-density lipoprotein [LDL] cholesterol) were associated with POAG. CONCLUSIONS: Overall, these results suggest that the relationship between HDL3 cholesterol and POAG might be causal and specific, and that dysregulation of cholesterol transport may play a role in the pathogenesis of POAG.


Assuntos
HDL-Colesterol/sangue , Glaucoma de Ângulo Aberto/sangue , Análise da Randomização Mendeliana , Metabolômica , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Feminino , Estudo de Associação Genômica Ampla , Glaucoma de Ângulo Aberto/diagnóstico , Gonioscopia , Humanos , Espectroscopia de Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Razão de Chances , Polimorfismo de Nucleotídeo Único , Microscopia com Lâmpada de Fenda , Tonometria Ocular
6.
Ophthalmology ; 129(7): 792-802, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35306094

RESUMO

PURPOSE: To determine the incidence and risk factors of primary angle-closure disease (PACD) over 6 years in a multi-ethnic Asian population. DESIGN: Population-based, longitudinal study. PARTICIPANTS: The Singapore Epidemiology of Eye Diseases study is a population-based cohort study conducted among adults aged 40 years or more. The baseline examination was conducted between 2004 and 2010, and the 6-year follow-up visit was conducted between 2011 and 2017. Of 6762 participants who attended the follow-up examination, 5298 at risk for primary angle-closure glaucoma (PACG) and 5060 at risk for PACD were included for analyses. METHODS: Standardized examinations including slit-lamp biomicroscopy, indentation gonioscopy, intraocular pressure (IOP) measurement, and static automated perimetry were performed. In this study, PACD includes primary angle-closure suspect (PACS), primary angle-closure (PAC), and PACG. MAIN OUTCOME MEASURES: The 6-year PACD incidence was evaluated among an at-risk population excluding adults with baseline glaucoma, PACS, PAC, pseudophakia at baseline or follow-up, or laser peripheral iridotomy or iridectomy at baseline visit. Logistic regression analysis adjusting for age, gender, and ethnicity was performed to evaluate associations between PACD development and demographic or ocular characteristics. Forward selection based on the Quasi-likelihood Information Criterion was used in multivariable analysis to reduce potential multicollinearity. RESULTS: The 6-year age-adjusted PACD incidence was 3.50% (95% confidence interval [CI], 2.94-4.16). In multivariable analysis, increasing age per decade (odds ratio [OR], 1.35; 95% CI, 1.15-1.59), higher IOP (OR, 1.04; 95% CI, 1.00-1.08), and shallower anterior chamber depth (OR, 1.11; 95% CI, 1.08-1.14) at baseline were associated with higher odds of PACD, whereas late posterior subcapsular cataract (PSC) (OR, 0.60; 95% CI, 0.48-0.76) was associated with lower odds of PACD. The 6-year age-adjusted incidences of PACG, PAC, and PACS were 0.29% (95% CI, 0.14-0.55), 0.46% (95% CI, 0.29-0.75), and 2.54% (95% CI, 2.07-3.12), respectively. CONCLUSIONS: Our study showed that the 6-year incidence of PACD was 3.50%. Increasing age, higher IOP, and shallower anterior chamber were associated with a higher risk of incident PACD, whereas late PSC was associated with a lower odds of PACD. These findings can aid in future projections and formulation of health care policies for screening of at-risk individuals for timely intervention.


Assuntos
Glaucoma de Ângulo Fechado , Adulto , Estudos de Coortes , Glaucoma de Ângulo Fechado/diagnóstico , Glaucoma de Ângulo Fechado/epidemiologia , Glaucoma de Ângulo Fechado/cirurgia , Gonioscopia , Humanos , Incidência , Pressão Intraocular , Iridectomia/métodos , Estudos Longitudinais , Fatores de Risco , Singapura/epidemiologia
7.
Age Ageing ; 51(4)2022 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-35363255

RESUMO

BACKGROUND: ageing is an important risk factor for a variety of human pathologies. Biological age (BA) may better capture ageing-related physiological changes compared with chronological age (CA). OBJECTIVE: we developed a deep learning (DL) algorithm to predict BA based on retinal photographs and evaluated the performance of our new ageing marker in the risk stratification of mortality and major morbidity in general populations. METHODS: we first trained a DL algorithm using 129,236 retinal photographs from 40,480 participants in the Korean Health Screening study to predict the probability of age being ≥65 years ('RetiAGE') and then evaluated the ability of RetiAGE to stratify the risk of mortality and major morbidity among 56,301 participants in the UK Biobank. Cox proportional hazards model was used to estimate the hazard ratios (HRs). RESULTS: in the UK Biobank, over a 10-year follow up, 2,236 (4.0%) died; of them, 636 (28.4%) were due to cardiovascular diseases (CVDs) and 1,276 (57.1%) due to cancers. Compared with the participants in the RetiAGE first quartile, those in the RetiAGE fourth quartile had a 67% higher risk of 10-year all-cause mortality (HR = 1.67 [1.42-1.95]), a 142% higher risk of CVD mortality (HR = 2.42 [1.69-3.48]) and a 60% higher risk of cancer mortality (HR = 1.60 [1.31-1.96]), independent of CA and established ageing phenotypic biomarkers. Likewise, compared with the first quartile group, the risk of CVD and cancer events in the fourth quartile group increased by 39% (HR = 1.39 [1.14-1.69]) and 18% (HR = 1.18 [1.10-1.26]), respectively. The best discrimination ability for RetiAGE alone was found for CVD mortality (c-index = 0.70, sensitivity = 0.76, specificity = 0.55). Furthermore, adding RetiAGE increased the discrimination ability of the model beyond CA and phenotypic biomarkers (increment in c-index between 1 and 2%). CONCLUSIONS: the DL-derived RetiAGE provides a novel, alternative approach to measure ageing.


Assuntos
Aprendizado Profundo , Idoso , Envelhecimento/fisiologia , Humanos , Morbidade , Modelos de Riscos Proporcionais , Fatores de Risco
8.
Ophthalmology ; 128(10): 1393-1404, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-33865875

RESUMO

TOPIC: Glaucoma is the leading cause of irreversible blindness, despite having good prognosis with early treatment. We evaluated the global extent of undetected glaucoma and the factors associated with it in this systematic review and meta-analysis. CLINICAL RELEVANCE: Undetected glaucoma increases the risk of vision impairment, which leads to detrimental effects on the quality-of-life and socioeconomic well-being of those affected. Detailed information on the extent and factors associated with undetected glaucoma aid in the development of public health interventions. METHODS: We conducted a systematic review and meta-analysis of population-based studies published between January 1, 1990, and June 1, 2020. Article search was conducted in online databases (PubMED, Web-of-Science), grey literatures (OpenGrey), and nongovernment organization reports. Our outcome measure was the proportion of glaucoma cases that were undetected previously. Manifest glaucoma included any form of glaucoma reported in the original studies and may include primary open-angle glaucoma (POAG), primary angle-closure-glaucoma, secondary glaucoma, or a combination thereof. Undetected glaucoma was defined as glaucoma cases that were undetected prior to diagnosis in the respective study. Random-effect meta-analysis was used to estimate the pooled proportion of undetected glaucoma. We followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses and the Meta-analysis of Observational Studies in Epidemiology guidelines in our study. RESULTS: We identified 61 articles from 55 population-based studies (n = 189 359 participants; n = 6949 manifest glaucoma). Globally, more than half of all glaucoma cases were undetected previously on average in each geographical region. Africa (odds ratio [OR], 12.70; 95% confidence interval [CI], 4.91-32.86) and Asia (OR, 3.41; 95% CI, 1.63-7.16) showed higher odds of undetected glaucoma as compared with Europe. Countries with low Human Development Index (HDI; <0.55) showed a higher proportion of undetected manifest glaucoma as compared with countries of medium to very high HDI (≥0.55; all P < 0.001). In 2020, 43.78 million POAG cases were projected to be undetected, of which 76.7% were in Africa and Asia. DISCUSSION: Undetected glaucoma is highly prevalent across diverse communities worldwide and more common in Africa and Asia. Strategies to improve detection are needed to prevent excess visual disability and blindness resulting from glaucoma.


Assuntos
Glaucoma/diagnóstico , Adulto , Glaucoma/epidemiologia , Saúde Global , Humanos , Prevalência
9.
Ophthalmology ; 128(3): 354-363, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-32738259

RESUMO

PURPOSE: Visual impairment (VI) can have a detrimental impact on vision-related quality of life (VRQoL), but it is still unclear how this relationship varies with age across the VI spectrum. We determined the age-stratified, cross-sectional, and longitudinal associations between VI severity and VRQoL. DESIGN: The baseline and follow-up Singapore Chinese Eye Studies (SCES-1/-2; 2009-2011 and 2015-2017). PARTICIPANTS: A total of 3068 SCES-1 participants (mean age [standard deviation {SD}]: 59.5 [9.8] years; 50.2% female) and 1919 SCES-2 participants (mean age [SD]: 56.8 [8.3] years; 49.9% female). METHODS: Visual impairment was defined as visual acuity (VA) of > 0.3 logarithm of the minimum angle of resolution (logMAR) units; VI severity as mild-moderate (logMAR scores less than the median of all individuals with VI) and severe (logMAR scores median or greater); and VI incidence as VI absence at baseline, but evident at follow-up. Age was stratified into 40 to 49 years, 50 to 64 years, and ≥65 years. MAIN OUTCOME MEASURES: Rasch-transformed scores from the 32-item Impact of Visual Impairment (IVI) questionnaire were used to measure the "Reading," "Mobility," and "Emotional" domains of VRQoL. Multiple linear regression models determined the age-stratified associations of prevalent and incident VI with all 3 VRQoL outcomes, adjusted for potential confounders. RESULTS: Of the 807 persons with prevalent VI, 55.9% had mild-moderate and 44.1% had severe VI. Compared with no VI, age-stratified analyses showed that VRQoL decrements were significant only in the older age groups (mild-moderate VI: 6.2% and 8.1% reduction in Mobility and Reading scores in those aged ≥ 65 years; severe VI: 8.5% to 13.4% reductions in the 3 VRQoL scores in those aged ≥ 50 years). This interaction with older age became more pronounced with incident VI (N = 168), where decrements in all 3 VRQoL domains were evident only in those aged ≥65 years compared with persons without incident VI. CONCLUSIONS: Our results suggest that the VI-VRQoL associations are driven mainly by older individuals aged ≥65 years, highlighting the need for effective regular screening and early intervention modalities to prevent the presence and onset of VI, and subsequent VRQoL declines, in these individuals.


Assuntos
Qualidade de Vida/psicologia , Transtornos da Visão/psicologia , Visão Ocular/fisiologia , Pessoas com Deficiência Visual/estatística & dados numéricos , Fatores Etários , Idoso , Povo Asiático/etnologia , Estudos Transversais , Feminino , Seguimentos , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Prevalência , Perfil de Impacto da Doença , Singapura/epidemiologia , Inquéritos e Questionários , Transtornos da Visão/epidemiologia , Acuidade Visual/fisiologia
10.
Ophthalmology ; 128(3): 393-400, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-32739337

RESUMO

PURPOSE: To evaluate the association between different classes of antihypertensive medication with retinal nerve fiber layer (RNFL) and ganglion cell-inner plexiform layer (GC-IPL) thickness in a nonglaucomatous multiethnic Asian population. DESIGN: Population-based, cross-sectional study. PARTICIPANTS: A total of 9144 eyes for RNFL analysis (2668 Malays, 3554 Indians, and 2922 Chinese) and 8549 eyes for GC-IPL analysis (2460 Malays, 3230 Indians, and 2859 Chinese) aged 44 to 86 years. METHODS: Participants underwent standardized systemic and ocular examinations and interviewer-administered questionnaires for collection of data on medication and other variables. Intraocular pressure (IOP) readings were obtained by Goldmann applanation tonometry before pupil dilation for fundoscopy and OCT imaging. Blood pressure (BP) was measured with an automatic BP monitor. Mean arterial pressure (MAP) was defined as diastolic BP plus 1/3 (systolic BP - diastolic BP). Regression models were used to investigate the association of antihypertensive medication with OCT measurements of RNFL and GC-IPL. MAIN OUTCOME MEASURES: Average and sectoral RNFL and GC-IPL thickness. RESULTS: After adjusting for age, gender, ethnicity, MAP, IOP, body mass index (BMI), and presence of diabetes, we found that participants taking any type of antihypertensive medication (ß = -0.83; 95% confidence interval [CI], -1.46 to -0.02; P = 0.01), specifically angiotensin-converting enzyme inhibitors (ACEIs) (ß = -1.66; 95% CI, -2.57 to -0.75; P < 0.001) or diuretics (ß = -1.38; 95% CI, -2.59 to -0.17; P < 0.05), had thinner average RNFL in comparison with participants who were not receiving antihypertensive treatment. Use of a greater number of antihypertensive medications was significantly associated with thinner average RNFL (P for trend = 0.001). This association was most evident in the inferior RNFL quadrant in participants using ACEIs (ß = -2.44; 95% CI, -3.99 to -0.89; P = 0.002) or diuretics (ß = -2.76; 95% CI, -4.76 to -0.76; P = 0.007). A similar trend was noted in our analysis of macular GC-IPL thickness. CONCLUSIONS: Use of 2 or more antihypertensive medications, ACEI, and diuretics were associated with a loss of structural markers of retinal ganglion cell health in a multiethnic Asian population.


Assuntos
Inibidores da Enzima Conversora de Angiotensina/efeitos adversos , Anti-Hipertensivos/efeitos adversos , Diuréticos/efeitos adversos , Fibras Nervosas/efeitos dos fármacos , Doenças Retinianas/induzido quimicamente , Células Ganglionares da Retina/efeitos dos fármacos , Neurônios Retinianos/efeitos dos fármacos , Adulto , Idoso , Idoso de 80 Anos ou mais , Pressão Arterial/efeitos dos fármacos , Pressão Sanguínea/efeitos dos fármacos , Estudos Transversais , Feminino , Humanos , Pressão Intraocular , Masculino , Pessoa de Meia-Idade , Fibras Nervosas/patologia , Doenças Retinianas/diagnóstico , Células Ganglionares da Retina/patologia , Neurônios Retinianos/patologia , Inquéritos e Questionários , Tomografia de Coerência Óptica , Tonometria Ocular
11.
Int Ophthalmol ; 41(2): 483-490, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33051769

RESUMO

PURPOSE: The current grading systems used for bleb morphology assessment in patients post-trabeculectomy are based on standardized slit-lamp photographs and anterior segment imaging devices. The lack of availability of these expensive and non-portable devices in resource-deficient settings is a significant deterrent in their widespread utilization for proper post-operative management. The rapidly evolving utilization of smartphone photography has significantly benefited diagnostics of posterior segment disorders and is now being increasingly utilized for monitoring anterior segment pathologies as well as post-surgical course. In this study, we study a novel use of smartphones for bleb photography for assessing the morphological characteristics as vascularity and microcysts. METHODS: In this pilot, observational study, we compared the trabeculectomy bleb images of five subjects, obtained by iPhone X (dual lens) and iPhone 6S (single lens). We captured two image sets with both smartphones first with a focussed torchlight and then with a built-in flash video light. RESULTS: The images resulting from the newer iPhone X were substantially superior than those from iPhone 6S. For the 12-megapixel dual-camera set-up on the iPhone X, the 1 × lens resulted in better images than the 2 × lens with contrast and overall clarity of the area of interest. While the macro-lens attachment had promising results at 1 × zoom, there is no added advantage of the macro-lens attachment as it resulted in considerable loss of image quality at twice the zoom. Using a 20 D lens helped attain higher magnification and better framing as it reduced the focussing distance needed to get sharp images. The images obtained from both smartphones were of higher quality when illuminated from an external source when compared to the native iPhone flash due to even exposure and fewer autofocus artefacts. CONCLUSION: Analyses of all image sets showed that the current generation in-built camera app on IOS and newer iPhone camera optics resulted in high-quality images of the ocular surface with high magnification without any loss in clarity.


Assuntos
Smartphone , Trabeculectomia , Humanos , Fotografação , Projetos Piloto
12.
Ophthalmology ; 127(9): 1145-1151, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32222400

RESUMO

PURPOSE: Although the impact of vision-related quality of life (VRQoL) is assessed optimally using binocular visual acuity (VA), uniocular VA remains the preferred measurement method in clinic-based and epidemiologic studies. We compared the impact of distance presenting binocular VA and uniocular VA in the better-seeing (better-eye VA) and worse-seeing (worse-eye VA) eye on VRQoL. DESIGN: The Singapore Chinese Eye Study 2 (2015-2017), a population-based, cross-sectional study. PARTICIPANTS: One thousand eight hundred twenty-two individuals (mean age, 66.2 years [standard deviation, 8.9 years]; 51.1% women) were included. METHODS: Presenting uniocular VA and binocular VA were assessed using a logarithm of the minimum angle of resolution number chart at a distance of 4 m under standard lighting by trained and certified study optometrists. Multiple linear regression models were constructed to determine the independent associations between binocular VA, better-eye VA, and worse-eye VA and the outcome (VRQoL), adjusted for potential confounders, including age, gender, socioeconomic status, and presence of comorbidities. In addition, a cluster sandwich estimator was used to determine if any differences in ß estimates between the associations were statistically significant. MAIN OUTCOME MEASURES: Vision-related quality of life was measured using Rasch-transformed scores from the emotional, mobility, and reading domains of the Impact of Visual Impairment (IVI) questionnaire. RESULTS: Although every 2-line increase (worsening) in binocular VA and uniocular VA was associated independently with decrements in emotional, mobility, and reading IVI scores (P < 0.05 for all), the reductions in all VRQoL domains were substantially lower (P < 0.1) when using either the better-eye VA (compared with binocular VA ß-estimates, -27.8%, -19.4%, and -24.2% difference in emotional, mobility, and reading IVI scores, respectively) or worse-eye VA (compared with binocular VA ß estimates, -38.9%, -58.1%, and -57.5% reduction in emotional, mobility, and reading IVI scores, respectively) to quantify vision loss. CONCLUSIONS: Uniocular VA seems to underestimate the impact of vision loss on VRQoL indices compared with binocular VA. Our data suggest that researchers, clinicians, and policy planners should consider using binocular instead of uniocular measures of VA in patient-reported outcome evaluation of vision loss because it may better reflect its impact on VRQoL.


Assuntos
Qualidade de Vida/psicologia , Transtornos da Visão/fisiopatologia , Visão Binocular/fisiologia , Visão Monocular/fisiologia , Acuidade Visual/fisiologia , Adulto , Idoso , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Medidas de Resultados Relatados pelo Paciente , Estudos Prospectivos , Perfil de Impacto da Doença , Singapura , Inquéritos e Questionários , Transtornos da Visão/psicologia , Testes de Campo Visual , Campos Visuais/fisiologia
13.
Ophthalmology ; 127(8): 1064-1076, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32197910

RESUMO

PURPOSE: To examine the normative profile and determinants of macular ganglion cell-inner plexiform layer (GCIPL) thickness based on spectral-domain OCT (SD-OCT) in a nonglaucoma, multi-ethnic Asian population. DESIGN: Population-based, cross-sectional study. PARTICIPANTS: Ethnic Chinese, Malay, and Indian adults aged ≥40 years recruited from the Singapore Epidemiology of Eye Diseases Study. METHODS: All participants underwent standardized examinations. The GCIPL thickness was measured using Cirrus HD-OCT (Carl Zeiss Meditec, Dublin, CA). Participants with glaucoma or poor-quality scans were excluded. Eye-specific data were used. Associations of ocular and systemic factors with GCIPL thickness parameters were investigated using multivariable linear regression with generalized estimating equation models to account for correlation between both eyes. MAIN OUTCOME MEASURES: GCIPL thickness. RESULTS: A total of 4464 participants (7520 eyes) consisting of 1625 Chinese, 1212 Malay, and 1627 Indian adults contributed to this analysis. Average GCIPL thickness was 82.6±6.1 µm in Chinese, 81.5±6.8 µm in Malays, and 78.0±6.9 µm in Indians (P < 0.001 by analysis of variance). The 5th percentile limit of average GCIPL thickness was 72 µm in Chinese, 70 µm in Malays, and 67 µm in Indians. In multivariable analysis adjusting for age, gender, axial length, presence of cataract, OCT signal strength, disc area, hypertension, diabetes, and hyperlipidemia, eyes of Indians were observed to have 3.43 µm thinner GCIPL on average compared with Chinese (P < 0.001) and 3.36 µm thinner GCIPL compared with Malays (P < 0.001). In addition, older age (per decade; ß = -2.51), female (ß = -1.57), longer axial length (per mm; ß = -1.54), and presence of chronic kidney disease (ß = -1.49) were significantly associated with thinner average GCIPL (all P ≤ 0.008). Larger optic disc area (per mm2; ß = 0.78; P < 0.001) was associated with thicker GCIPL. These factors were consistently observed to be significant for superior and inferior hemisphere GCIPL thickness. CONCLUSIONS: GCIPL thickness profiles were significantly thinner in Indians compared with Chinese and Malays. Our findings further highlight the need of a more refined, ethnic-specific normative database for GCIPL thickness, which in turn may improve the detection and diagnosis of glaucoma in Asians.


Assuntos
Etnicidade , Glaucoma/etnologia , Vigilância da População , Células Ganglionares da Retina/patologia , Estudos Transversais , Feminino , Glaucoma/diagnóstico , Humanos , Masculino , Pessoa de Meia-Idade , Fibras Nervosas , Disco Óptico , Singapura/epidemiologia , Tomografia de Coerência Óptica
14.
Clin Exp Ophthalmol ; 48(9): 1210-1218, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32734654

RESUMO

IMPORTANCE: Evidence-based guidelines are essential for glaucoma screening to work effectively. BACKGROUND: To derive a vertical cup-to-disc ratio (VCDR) cut-off for glaucoma screening in a multi-ethnic Asian population. DESIGN: The Singapore Epidemiology of Eye Diseases (SEED) study is a population-based study conducted from 2004 to 2011 in a single tertiary care research institute. PARTICIPANTS: SEED comprised of 10 033 Chinese, Malay and Indian adults aged ≥40 (response rate 75.6%). After excluding participants with a history of glaucoma medication or surgery, 9673 participants were included for analysis. METHODS: A systematic eye examination, which included applanation tonometry, visual field testing, gonioscopy and dilated fundus examination was conducted. MAIN OUTCOME MEASURE: Diagnosis of glaucoma. RESULTS: The distribution of VCDR and VCDR asymmetry were relatively homogenous in this multi-ethnic Asian population, with a 97.5th percentile value of 0.67 and 0.17, respectively. In the absence of more definite signs of glaucoma, VCDR ≥0.60 and VCDR asymmetry ≥0.20 provided the best balance between sensitivity (95.1%) and specificity (90.9%) in detecting glaucoma. For larger optic disc (≥2.0 mm), VCDR ≥0.65 with VCDR asymmetry ≥0.20 provided the best balance between sensitivity (84.8%) and specificity (93.2%). CONCLUSION AND RELEVANCE: Overall, VCDR ≥0.60 with VCDR ≥0.20 asymmetry provides a good balance between sensitivity and specificity in detecting glaucoma. For larger optic disc, VCDR ≥0.65 should be considered instead to mitigate against false-referrals due to larger physiological disc cupping. Our findings may act as a reference to populations with similar VCDR distribution.


Assuntos
Glaucoma , Disco Óptico , Adulto , Técnicas de Diagnóstico Oftalmológico , Humanos , Pressão Intraocular , Tonometria Ocular , Testes de Campo Visual
15.
Int Ophthalmol ; 40(11): 3187-3207, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32617804

RESUMO

PURPOSE: To review the current regimens and novel therapeutic modalities in various stages of research and development for the management of non-infectious posterior uveitis (NIPU). METHODS: We performed a thorough review of current literature using PubMed, Google Scholar and Clinicaltrials.gov to identify the published literature about the available therapeutics and novel drugs/therapies in different stages of clinical trials. RESULTS: The current management regimen for non-infectious posterior uveitis includes corticosteroids, immunomodulatory therapies and anti-metabolites. However, NIPU requires long-term management for efficacious remission of the disease and to prevent disease relapse. Long-term safety issues associated with steroids have led to efforts to develop novel therapeutic agents including biological response modulators and immunosuppressants. The current therapeutic agents in various stages of development include calcineurin inhibitors, biologic response modifiers and a more a comprehensive modalities like ocular gene therapy as well as novel drug delivery mechanisms for higher bioavailability to the target tissues, with minimal systemic effects. CONCLUSION: Novel efficacious therapeutic modalities under development will help overcome the challenges associated with the traditional therapeutic agents.


Assuntos
Uveíte Posterior , Uveíte , Corticosteroides/uso terapêutico , Humanos , Imunossupressores/uso terapêutico
16.
BMC Ophthalmol ; 19(1): 76, 2019 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-30866885

RESUMO

PURPOSE: To evaluate the use of digital devices, reading habits and the prevalence of eyestrain among urban Indian school children, aged 11-17 years. METHODS: The study included 576 adolescents attending urban schools who were surveyed regarding their electronic device usage. Additional information on the factors that may have an effect on ocular symptoms was collected. RESULTS: Twenty percent of students aged 11 in the study population use digital devices on a daily basis, in comparison with 50% of students aged 17. In addition to using these devices as homework aids, one third of study participants reported using digital devices for reading instead of conventional textbooks. The majority of students preferred sitting on a chair while reading (77%; 445 students), with only 21% (123 students) preferring to lie on the bed and 8 students alternating between chair and bed. There was a significant association between the students who preferred to lie down and those who experienced eyestrain, as reported by a little over one fourth of the student population (27%). Out of 576 students, 18% (103) experienced eyestrain at the end of the day after working on digital devices. CONCLUSIONS: The increased use of digital devices by adolescents brings a new challenge of digital eyestrain at an early age. Our study reports the patterns of electronic device usage by school children, evaluates factors associated with eyestrain and highlights the need for further investigation of these issues.


Assuntos
Astenopia/epidemiologia , Computadores de Mão , Leitura , Instituições Acadêmicas/estatística & dados numéricos , Adolescente , Criança , Estudos Transversais , Feminino , Humanos , Índia/epidemiologia , Projetos Piloto , Prevalência
18.
Indian J Ophthalmol ; 72(3): 312-319, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38421290

RESUMO

Selective laser trabeculoplasty (SLT) has experienced a resurgence in interest, primarily driven by promising findings from the Laser in Glaucoma and Ocular Hypertension Trial. By offering SLT as an initial drug-free treatment option, we may be able to thwart issues such as adherence and persistence that plague our current medical management protocols. In this comprehensive narrative review, we delve into the current body of literature that explores the utility of SLT across a wide spectrum of scenarios and glaucoma subtypes. We present evidence that provides valuable insight into the efficacy and benefits of SLT, positioning it as a viable option in the management of glaucoma. Careful consideration of the associated risks and challenges is also necessary for successful adoption into clinical practice. Despite the ample evidence supporting SLT's efficacy, some questions remain regarding its long-term effects and the potential need for retreatment. This review aims to shed light on these aspects to guide clinicians in making informed decisions and tailoring treatment plans to individual patient needs. This review also provides the readers with a bird's eye view of the potential impact of SLT and adds clarity to the various therapeutic protocols that one can follow to ensure optimal clinical outcomes for our patients.


Assuntos
Glaucoma , Terapia a Laser , Trabeculectomia , Humanos , Glaucoma/cirurgia , Tomada de Decisões , Ácido Láctico
19.
Dalton Trans ; 2024 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-39446127

RESUMO

This work is based on probing photosensitization in carbon nanotubes (CNTs) by organotin(IV) compounds to fabricate a hybrid material with excellent photocatalytic activity and generation of reactive oxygen species. Two organotin(IV) compounds (compounds 1 and 2) were synthesized and characterized by spectroscopic and spectrometric studies, elemental analysis and single crystal X-ray diffraction followed by their impregnation inside the CNTs. The so obtained hybrid materials (1@CNT and 2@CNT) were characterized by FTIR, TGA, FE-SEM, HR-TEM, PXRD and XPS analysis, and assessed for photosensitization and generation of reactive oxygen species. The enhanced photocatalytic activity of the fabricated materials in comparison to bare CNTs is attributed to the reduction of band gap and suppression of rapid recombination rates due to the encapsulation of photogenerated electrons. The generation of reactive species in photocatalyst 1@CNT was validated by the degradation of Amoxicillin (AMX) under optimized conditions for catalytic dosage, H2O2 concentration, response time and pH. The material 1@CNT could degrade ca. 83% of AMX by generating free radicals (˙OH and ˙O2-) under visible light irradiation at pH 6 as investigated by UV-visible spectroscopy and supported by EPR and DFT studies. Furthermore, the structural stability and sustained photocatalytic properties of 1@CNT over four cycles highlight its potential as an eco-friendly solution for degrading environmental toxins.

20.
Chemosphere ; 352: 141483, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38378052

RESUMO

Contaminants of emerging concern (CEC) contain a wide range of compounds, such as pharmaceutical waste, pesticides, herbicides, industrial chemicals, organic dyes, etc. Their presence in the surrounding has extensive and multifaceted effects on human health as they have the potential to persist in the environment, accumulate in biota, and disrupt ecosystems. In this regard, various remediation methods involving different kind of functional nanomaterials with unique properties have been developed. The functional nanomaterials can provide several mechanisms for water pollutant removal, such as adsorption, catalysis, and disinfection, in a single platform. Graphene oxide (GO) is a two-dimensional carbon-based material that has an extremely large surface area and a large number of active sites. Recent advances in synthesising GO have shown great progress in tailoring its various physiochemical, optical, surface, structural properties etc., making it better adsorbent and photocatalysts. In this review, sole adsorbent and standalone photocatalytic performances of GO for the removal of CEC have been discussed in light of tailoring its adsorption and photocatalytic properties through novel synthesis routes and optimizing synthesis parameters. This review also examines various models describing the structure of GO and its surface/structural modifications for improved adsorption and photocatalytic properties. The article provides valuable information for the production of efficient and cost-effective GO-based sole adsorbents and photocatalysts as compared to the traditional materials. Furthermore, future prospective and challenges for sole GO nanostructures to compete with traditional adsorbents and photocatalysts have been discussed providing interesting avenues for future research.


Assuntos
Grafite , Nanoestruturas , Humanos , Ecossistema , Grafite/química , Carbono , Adsorção
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