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SiO2@Ag nanocomposite (NC) has been synthesized by the chemical reduction and StÓ§ber method for Metal-enhanced fluorescence (MEF) of Rhodmine 6G (R6G) and Surface-enhanced Raman spectroscopy (SERS) of Malachite green (MG). As-synthesized SiO2@Ag NC indicated SiO2 nanosphere (NS) and Ag nanoparticle (NP) morphologies. The SiO2@Ag NC was high quality with a well-defined crystallite phase with average sizes of 24 nm and 132 nm for Ag NP and SiO2 NC, respectively. By using SiO2@Ag NC, the photoluminescence (PL) intensity of the R6G (at 59.17 ppm) was increased approximately 133 times. The SERS of the MG (at 1.0 ppm) with SiO2@Ag NC as substrate clearly observed vibrational modes in MG dye at 798, 916, 1172, 1394, and 1616 cm-1. As a result, the SERS enhancement factor (EFSERS) at 1172 cm-1 obtained 6.3 × 106. This initial study points to the potential of SiO2@Ag NC as a promising material for MEF and SERS substrates to detect dyes at low concentrations.
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PURPOSE: To investigate the relationship between the macular values of fractal dimension (FD) and lacunarity (LAC) on optical coherence tomography angiography (OCTA) images and the presence of peripheral retina non-perfusion areas (NPAs) on fluorescein angiography (FA) in patients with treatment-naïve diabetic macular edema (DME). METHODS: Fifty patients with treatment-naïve DME underwent a full ophthalmic examination, including best-corrected visual acuity measurement, FA, spectral-domain optical coherence tomography, and OCTA. Specifically, FA was performed to detect the presence of retinal NPAs, whereas fractal OCTA analysis was used to determine macular FD and LAC values at the level of the superficial and deep capillary plexus (SCP and DCP). FA montage frames of the posterior pole and peripheral retina, as well as macular OCTA slabs of the SCP and DCP, were obtained. RESULTS: Thirty (60%) eyes with FA evidence of peripheral retinal NPAs in at least one quadrant showed significantly lower FD and higher LAC in both SCP and DCP, when compared with eyes presenting a well-perfused peripheral retina. Furthermore, macular FD and LAC values were found to be significantly associated with the extent of retinal NPAs. CONCLUSIONS: Macular FD and LAC of both SCP and DCP seem to be strongly associated with the extent of peripheral retinal NPAs, thus suggesting that may be useful predictive biomarkers of peripheral ischemia in treatment-naïve DME eyes.
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Retinopatia Diabética , Angiofluoresceinografia , Fundo de Olho , Isquemia , Edema Macular , Vasos Retinianos , Tomografia de Coerência Óptica , Acuidade Visual , Humanos , Tomografia de Coerência Óptica/métodos , Edema Macular/diagnóstico , Edema Macular/etiologia , Edema Macular/metabolismo , Retinopatia Diabética/diagnóstico , Retinopatia Diabética/metabolismo , Retinopatia Diabética/fisiopatologia , Angiofluoresceinografia/métodos , Masculino , Feminino , Vasos Retinianos/diagnóstico por imagem , Isquemia/diagnóstico , Isquemia/fisiopatologia , Isquemia/metabolismo , Pessoa de Meia-Idade , Macula Lutea , Idoso , Biomarcadores/metabolismo , Fóvea Central , Seguimentos , Estudos ProspectivosRESUMO
BACKGROUND: Although ocular adverse events are frequent in AD patients treated with dupilumab, their characterization remains limited due to a lack of prospective studies with a systematic ophthalmological examination. OBJECTIVE: To examine the incidence, characteristics and risk factors of dupilumab-induced ocular adverse events. METHODS: A prospective, multicenter, and real-life study in adult AD patients treated with dupilumab. RESULTS: At baseline, 27 out of 181 patients (14.9%) had conjunctivitis. At week 16 (W16), 25 out of 27 had improved their conjunctivitis and 2 remained stable and 34 out of 181 patients (18.7%) had dupilumab-induced blepharoconjunctivitis: either de novo (n = 32) or worsening of underlying blepharoconjunctivitis (n = 2). Most events (27/34; 79.4%) were moderate. A multivariate analysis showed that head and neck AD (OR = 7.254; 95%CI [1.938-30.07]; p = 0.004), erythroderma (OR = 5.635; 95%CI [1.635-21.50]; p = 0.007) and the presence of dry eye syndrome at baseline (OR = 3.51; 95%CI [3.158-13.90]; p = 0.031) were independent factors associated with dupilumab-induced blepharoconjunctivitis. LIMITATIONS: Our follow-up period was 16 weeks and some late-onset time effects may still occur. CONCLUSION: This study showed that most dupilumab-induced blepharoconjunctivitis cases are de novo. AD severity and conjunctivitis at baseline were not found to be associated risk factors in this study.
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Conjuntivite , Dermatite Atópica , Adulto , Humanos , Dermatite Atópica/tratamento farmacológico , Dermatite Atópica/diagnóstico , Estudos Prospectivos , Anticorpos Monoclonais Humanizados/efeitos adversos , Conjuntivite/induzido quimicamente , Conjuntivite/epidemiologia , Índice de Gravidade de Doença , Resultado do TratamentoRESUMO
SIGNIFICANCE: Vision is paramount for motor actions directed toward objects. Vision allows not only the identification of objects and their shape and spatial location, but also the adaptation of our movement when it arrives on the object. These findings show that vision deficits, as in age-related macular degeneration (AMD), can lead to reaching and grasping deficits. PURPOSE: Few studies have investigated reaching and grasping in patients with AMD. They showed a deficit in the execution of motor actions in people with AMD, even though these people do not mention difficulties in their daily lives. The purpose of this study was to understand the nature of impairments in motor actions in patients. METHODS: We compared performance in two reach-and-grasp tasks determined by whether the participants (16 people with wet AMD and 17 age-matched control subjects) had time to look at the object before reaching and grasping it. RESULTS: The results show that the kinematic parameters of reach-and-grasp movements do not differ between groups when participants are provided time to look at the object before the movement. In contrast, performance in terms of movement duration, acceleration time, time to reach the maximum grip aperture, and the maximum velocity differ between patients and control subjects when the object is displayed immediately before the movement. CONCLUSIONS: The motor perturbations observed in people with AMD in previous studies seem to result from difficulties in target identification rather than from visuomotor deficits.
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Força da Mão/fisiologia , Desempenho Psicomotor/fisiologia , Degeneração Macular Exsudativa/fisiopatologia , Idoso , Idoso de 80 Anos ou mais , Inibidores da Angiogênese/uso terapêutico , Fenômenos Biomecânicos , Feminino , Humanos , Injeções Intravítreas , Masculino , Pessoa de Meia-Idade , Movimento/fisiologia , Tempo de Reação , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Acuidade Visual/fisiologia , Degeneração Macular Exsudativa/tratamento farmacológicoRESUMO
PURPOSE: In our modern society, many touch screen applications require hand-eye coordination to associate an icon with its specific contextual unit on phones, on computers, or in public transport. We assessed the ability of patients with age-related macular degeneration (AMD) to explore scenes and to associate a target (animal or object) with a unique congruent scene (e.g., to match a fish with the sea) presented between three other distractors on a touch screen computer. METHODS: Twenty-four patients with AMD (64 to 90 years) with best-corrected visual acuity between 20/40 and 20/400 as well as 17 age-matched (60 to 94 years) and 15 young (22 to 34 years) participants with normal visual acuity had to match a target with a congruent scene by moving their index finger on a 22-in touch screen. RESULTS: Patients were as accurate (98.7% correct responses) as the age-matched control (98.9% correct responses) and young participants (99.3% correct responses) at performing the task. The duration of exploration was significantly longer for the AMD patients (mean, 4.13 seconds) compared with the age-matched group (mean, 2.96 seconds). The young participants were also significantly faster than the old group (mean, 0.93 seconds). The movement parameters of the older participants (patients and old control subjects) were affected compared with the young; the peak speed decreased (-8 cm/s) and the movement duration increased (+0.9 seconds) with age compared with the young group. CONCLUSIONS: People with AMD are able to perform a contextual association task on a touch screen with high accuracy. The AMD patients were specifically affected in the "exploration" phase; their accuracy and movement parameters did not differ from the old control group. Our study suggests that the decline associated with AMD is more focused on the duration of exploration than on movement parameters in touch screen use.
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Desempenho Psicomotor/fisiologia , Análise e Desempenho de Tarefas , Interface Usuário-Computador , Baixa Visão/fisiopatologia , Degeneração Macular Exsudativa/fisiopatologia , Idoso , Idoso de 80 Anos ou mais , Feminino , Angiofluoresceinografia , Humanos , Masculino , Pessoa de Meia-Idade , Reconhecimento Visual de Modelos/fisiologia , Tomografia de Coerência Óptica , Tato , Acuidade Visual/fisiologia , Degeneração Macular Exsudativa/diagnósticoRESUMO
PURPOSE: Previous studies showed that people with age-related macular degeneration (AMD) can categorise a pre-defined target object or scene with high accuracy (above 80%). In these studies participants were asked to detect the target (e.g. an animal) in serial visual presentation. People with AMD must rely on peripheral vision which is more adapted to the low resolution required for detection than for the higher resolution required to identify a specific exemplar. We investigated the ability of people with central vision loss to identify photographs of objects and scenes. METHODS: Photographs of isolated objects, natural scenes and objects in scenes were centrally displayed for 2 s each. Participants were asked to name the stimuli. We measured accuracy and naming times in 20 patients with AMD, 15 age-matched and 12 young controls. RESULTS: Accuracy was lower (by about 30%) and naming times were longer (by about 300 ms) in people with AMD than in age-matched controls in the three categories of images. Correct identification occurred in 62-66% of the stimuli for patients. More than 20% of the misidentifications resulted from a structural and/or semantic similarity between the object and the name (e.g. spectacles for dog plates or dolphin for shark). Accuracy and naming times did not differ significantly between young and older normally sighted participants indicating that the deficits resulted from pathology rather than to normal ageing. CONCLUSIONS: These results show that, in contrast to performance for categorisation of a single pre-defined target, people with central vision loss are impaired at identifying various objects and scenes. The decrease in accuracy and the increase in response times in patients with AMD indicate that peripheral vision might be sufficient for object and scene categorisation but not for precise scene or object identification.
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Degeneração Macular/psicologia , Reconhecimento Visual de Modelos/fisiologia , Transtornos da Percepção/etiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Feminino , Humanos , Degeneração Macular/complicações , Degeneração Macular/fisiopatologia , Masculino , Pessoa de Meia-Idade , Transtornos da Percepção/fisiopatologia , Estimulação Luminosa/métodos , Fotografação , Psicofísica , Baixa Visão/etiologia , Baixa Visão/fisiopatologia , Baixa Visão/psicologia , Acuidade Visual/fisiologia , Campos Visuais/fisiologia , Adulto JovemRESUMO
PURPOSE: To investigate the effect of age-related macular degeneration (AMD) on memory for spatial representations in realistic environments. METHODS: Participants were 19 patients with AMD and 13 age-matched observers. In a short-term spatial memory task, observers were first presented with one view of a scene (the prime view), and their task was to change the viewpoint forward or backward to match the prime view. Memory performance was measured as the number of snapshots between the selected view and the prime view. RESULTS: When selecting a match to the prime view, both people with AMD and those in the control group showed systematic biases toward the middle view of the range of snapshots. People with AMD exhibited a stronger middle bias after presentation of close and far prime views while navigating accurately after a middle prime view. No relation was found between visual acuity, visual field defect, or lesion size and the memory performance. CONCLUSIONS: Memory tasks using indoor scenes can be accomplished when central vision is impoverished, as with AMD. Stronger center bias for a scene location suggests that people with AMD rely more on their memory of a canonical view.
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Degeneração Macular/fisiopatologia , Memória de Curto Prazo/fisiologia , Reconhecimento Visual de Modelos/fisiologia , Percepção Espacial/fisiologia , Baixa Visão/fisiopatologia , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Testes de Inteligência , Masculino , Pessoa de Meia-Idade , Acuidade Visual/fisiologia , Campos Visuais/fisiologiaRESUMO
The aim of this study is to access the perifoveolar and peripapillary vascular density (VD) using optical coherence tomography-angiography (OCT-A) in eyes with optic neuritis (ON) and in fellow eyes, then compare that to healthy controls. METHOD: This is a cross-sectional study including 22 patients with unilateral ON and 20 control eyes of healthy subjects. A complete clinical examination and OCT-A were performed at least 6 months after the acute episode of optic neuritis. Vascular plexuses of the peripapillary and perifoveolar images obtained from OCT-A were used to calculate the VD in each plexus: superficial, deep, and peripapillary capillaries for each group (ON eyes, fellow eyes, healthy eyes). RESULTS: Compared to healthy control eyes, in the peripapillary area, we found a significant decrease in VD not only in ON eyes but also in fellow eyes in average (p ≤ 0.05) and in the temporal sector (p < 0.001). In the perifoveolar area, the VD of the superficial capillary plexus is decreased in all sectors (p < 0.001) in ON eyes and only in the upper sector (p = 0.037) of fellow eyes compared to control eyes. VD correlates with ganglion cell layer (GCL) thickness in ON and in fellow eyes. CONCLUSION: Peripapillary vascular density is decreased in both affected eyes and fellow eyes after a unilateral episode of optic neuritis, suggesting a subclinical involvement of the disease. Further studies are needed to clarify the mechanism and clinical implications of these data.
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PURPOSE: The purpose is to study the 5-year results of aflibercept monotherapy using an individualized regimen in naïve patients with neovascular AMD (nAMD). MATERIALS AND METHODS: This is a prospective observational study including naïve nAMD patients who underwent aflibercept injections with at least 5 years of follow-up. All of them received 3 monthly injections at the loading phase, followed by an observation period, then treated with an individualized treat-and-extend regimen. Visual acuity (VA) measurement and optical coherence tomography were performed at each visit. RESULTS: Forty-eight eyes were included. Of these, 30 were followed up for 5 years. The mean follow-up was 61.7 ± 2.3 months. The mean age was 81 ± 8 years. The visual gain was 7.3 ± 12.7 letters at 1 year, 6.5 ± 12.5 letters at 2 years, 5.2 ± 17 letters at 3 years, 6.2 ± 18.6 letters at 4 years, and 5.6 ± 20 letters at 5 years. At the last observation, 53% of eyes had VA > 70 letters. A complete fluid resolution was obtained in 53% of the eyes. At the 5-year endpoint, the total number of injections was 21.6 ± 13.4. Macular atrophy was observed in 18 eyes (60%) and subretinal fibrosis in 14 eyes (46%). CONCLUSION: Patients with exudative AMD can maintain their visual function at 5 years with aflibercept using an individualized treatment. The loss of visual gain beyond 2 years could be related to the natural progression of the disease than the direct effect of anti-vascular endothelial growth injections.
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Diabetic macular edema (DME) is a common cause of vision impairment in diabetic retinopathy. The aim of this study was to analyze the relationship between visual outcome and anatomic changes detected by traditional multimodal retinal imaging and optical coherence tomography angiography (OCTA) in DME eyes under treatment with Aflibercept. METHODS: Sixty-six DME eyes of 62 patients under treatment with intravitreal Aflibercept and with one-year follow-up were enrolled. All participants underwent a full ophthalmic evaluation, including best correct visual acuity (BCVA) measurement, spectral-domain optical coherence tomography, fluorescein angiography and OCTA, both at baseline and final examination. Fractal OCTA analysis of the superficial and deep capillary plexus (SCP and DCP) was performed to estimate vascular perfusion density and lacunarity (LAC). RESULTS: At the final examination, there was a significant improvement in terms of BCVA and central macular thickness (CMT). Furthermore, eyes with CMT <373 µm at baseline reached the higher BCVA at the last follow-up. Eyes with CMT ≥373 µm and DCP LAC <0.41 reached a higher final BCVA, if compared with eyes showing the same CMT but higher initial LAC. CONCLUSION: A 12-month treatment with intravitreal Aflibercept for DME resulted in significant visual and anatomic improvement. Multimodal retinal imaging, together with fractal OCTA analysis, may provide useful biomarkers, predictive of visual outcome in DME.
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BACKGROUND: To investigate changes in indocyanine green angiography (ICGA) features of occult choroidal neovascularization (CNV) after intravitreal ranibizumab injections. METHODS: We reviewed the charts of all consecutive patients with newly diagnosed occult CNV secondary to age-related macular degeneration (AMD) treated by intravitreal ranibizumab. In all patients, optical coherence tomography (OCT) and ICGA were performed at baseline, after 3 months and 12 months. RESULTS: Fifty-one eyes of 44 patients (ten males, 34 females, mean age 77.8 ± 7.3 years) were included. Mean follow-up was 20.3 ± 6.2 months. During the first 12 months, patients received 5.5 ± 2.7 intravitreal ranibizumab injections. When compared with baseline, best-corrected visual acuity (BCVA) significantly improved at the 3-month follow-up visit (60.5 ±22.0 vs 50.9 ±20.7 letters, p = 0.04), and stabilized at 12-month visit (55.7 ±18.2 letters; p = 0.05). Central macular thickness (CMT) significantly improved during follow-up (229.0 ±54.7 µm vs 281.0 ±61.3 µm at baseline, p = 0.003). An overall stabilization was observed on ICGA in both the lesion area (5.27 ± 3.9 mm(2) at baseline vs 4.60 ± 3.5 mm(2) at month 12, p = 0.4), and greatest linear dimension (GLD 2.66 ± 1.2 mm at baseline vs 2.55 ± 1.0 mm at month 12, p = 0.3). Eight eyes (15.7%) showed CNV growth on ICGA (lesion area 3.98 ± 3.2 mm2 at baseline vs 4.3 ± 2.7 mm2 at month-12, p = 0.6; GLD 2.11 ± 1.0 mm at baseline vs 2.70 ± 0.8 mm at month-12, p = 0.05). CONCLUSION: ICGA suggests that functional outcomes after intravitreal ranibizumab is related to CMT reduction rather than CNV regression.
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Inibidores da Angiogênese/administração & dosagem , Anticorpos Monoclonais Humanizados/administração & dosagem , Neovascularização de Coroide/diagnóstico , Neovascularização de Coroide/tratamento farmacológico , Corantes , Angiofluoresceinografia , Verde de Indocianina , Idoso , Neovascularização de Coroide/fisiopatologia , Feminino , Humanos , Injeções Intravítreas , Masculino , Ranibizumab , Tomografia de Coerência Óptica , Acuidade Visual/fisiologiaRESUMO
PURPOSE: To investigate the effect of contrast on scene perception in people with age-related macular degeneration (AMD) and to examine the relationship between task performance and macular function. METHODS: Nineteen patients with AMD and visual acuity below 20/50 were compared with 16 normally sighted, age-matched controls. Complete ophthalmologic examination (visual acuity, intraocular pressure measurement, and funduscopy) was performed in both patients and controls. In addition, Pelli-Robson contrast sensitivity, fluorescein angiography, and visual field size were assessed in the AMD study patients. The stimuli were photographs of natural scenes containing or lacking an animal (the target). For each scene, the contrast of the original photograph was divided by 2, 4, and 8 to yield versions with a residual contrast of 50, 25, and 12.5%, respectively. The four levels of contrast were presented randomly and participants were asked to press a key when they saw an animal. RESULTS: AMD patients exhibited a larger drop in target detection performance with the decrease in contrast than controls. We found a correlation between visual acuity and performance when the contrast was reduced to 50, 25, and 12.5% of the original value but not in the normal contrast condition. There were no correlations between letter contrast sensitivity, visual field lesion size, and performance. CONCLUSIONS: Our results suggest that optimal, stable contrast conditions would facilitate object recognition in everyday life for people with AMD.
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Atividades Cotidianas , Sensibilidades de Contraste , Iluminação/normas , Macula Lutea/fisiopatologia , Degeneração Macular/fisiopatologia , Reconhecimento Visual de Modelos/fisiologia , Idoso , Idoso de 80 Anos ou mais , Feminino , Angiofluoresceinografia , Seguimentos , Fundo de Olho , Humanos , Macula Lutea/patologia , Degeneração Macular/diagnóstico , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Campos VisuaisRESUMO
Human vision requires us to analyze the visual periphery to decide where to fixate next. In the present study, we investigated this process in people with age-related macular degeneration (AMD). In particular, we examined viewing biases and the extent to which visual salience guides fixation selection during free-viewing of naturalistic scenes. We used an approach combining generalized linear mixed modeling (GLMM) with a-priori scene parcellation. This method allows one to investigate group differences in terms of scene coverage and observers' well-known tendency to look at the center of scene images. Moreover, it allows for testing whether image salience influences fixation probability above and beyond what can be accounted for by the central bias. Compared with age-matched normally sighted control subjects (and young subjects), AMD patients' viewing behavior was less exploratory, with a stronger central fixation bias. All three subject groups showed a salience effect on fixation selection-higher-salience scene patches were more likely to be fixated. Importantly, the salience effect for the AMD group was of similar size as the salience effect for the control group, suggesting that guidance by visual salience was still intact. The variances for by-subject random effects in the GLMM indicated substantial individual differences. A separate model exclusively considered the AMD data and included fixation stability as a covariate, with the results suggesting that reduced fixation stability was associated with a reduced impact of visual salience on fixation selection.
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Fixação Ocular , Degeneração Macular , Humanos , Percepção Visual , Atenção , ViésRESUMO
Purpose: To evaluate the efficacy of intravitreal aflibercept injection (IAI) for vitrectomized eyes with diabetic macular edema (DME) at two years. Methods: This is a prospective, non-comparative, multicenter observational study including diabetic patients with visual acuity between 20/400 to 20/40 due to DME, who have undergone vitrectomy at least 3 months before the first aflibercept injection. Treatment protocol included 5 monthly aflibercept injection followed by a ProReNata regimen during the first year. Participants were managed at clinicians' discretion using Treat and Extend or Observe and Plan regimen during the second year. Visual acuity, OCT findings and number of IAI were assessed at two years. Results: Available data for 28 eyes with DME previously vitrectomized treated with aflibercept intravitreal injection during at least 2 years were collected. Visual gain was +5.4 letters (p = 0.01), and central macular thickness decreased significantly -62µm, p < 0.001) at 2 years. Resolution of macular edema allowing discontinuation of aflibercept was observed in 7 eyes (15%). Mean number of injections was 14.6, and mean interval injection was 6.4 weeks for 2 years. Conclusion: These results suggest that IAI is beneficial in vitrectomized eyes leading to improvement of visual and anatomical outcome which was maintained for 2 years.
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AIM: To evaluate the efficacy of intravitreal Aflibercept injection (IAI) for vitrectomized eyes with diabetic macular edema (DME) at one year. METHODS: This is a prospective, non-comparative, multicenter observational study including diabetic patients whose HbA1c is < 9%, with visual acuity between 20/400 to 20/40 due to DME, who have undergone vitrectomy since at least 3 months before the first aflibercept injection. Treatment protocol included 5 monthly aflibercept injection followed by a ProReNata regimen during the first year. Visual acuity, OCT findings and number of IAI were assessed at 6 months and one year. RESULTS: Forty-six eyes were included. Indications for vitrectomy were epiretinal membrane (58.7%), intravitreal hemorrhage (26.1%), and vitreomacular traction (8.7%), retinal detachment (4.3%), and other cause (4.3%). Median duration of macular edema was 3 years. Median interval between vitrectomy and first visit was 9 months. Thirty eyes were non-naïve and received previously thermal laser (44.3%), intravitreal injection of triamcinolone (26.7%), of ranibizumab (70%), of dexamethasone implant (36.7%), or bevacizumab (6.7%). Data was available for 35 eyes at 1 year. Visual gain was significant, +6 letters (p <0.001) and central subfield thickness (CST) decreased significantly (-108µm, p < 0.001) at 1 year. Mean number of injections was 9.3 and mean interval injection was 5.8 weeks. CONCLUSION: These results suggest that IAI may be beneficial in vitrectomized eyes with refractory DME which require frequent injections to obtain visual and anatomical improvement. CLINICAL TRIAL REGISTRATION: http://www.clinicaltrials.gov, registration Number NCT02874859.
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Zinc oxide (ZnO) is a well-known semiconductor with valuable characteristics: wide direct band gap of Ë3.3 eV, large exciton binding energy of 60 meV at room temperature, high efficient photocatalyst, etc. which have been applied in many fields such as optical devices (LEDs, laser), solar cells and sensors. Besides, various low dimensional structures of ZnO in terms of nanoparticles, nanorods, nanoneedles, nanotetrapods find applications in technology and life. This material is also appealing due to the diversity of available processing methods including both chemical and physical approaches such as: hydrothermal, sol-gel, chemical vapor deposition and sputtering. In this report, ZnO nanorods are prepared by hydrothermal method assisted with galvanic-cell effect. The effect of counter electrode materials on the morphology and structure of obtained product was studied. Scanning electron microscopy (SEM) images of the product showed that counter electrodes made of aluminum offers nanorods of higher quality than other materials in terms of uniform size, high density and good preferred orientation. The as-prepared nanorods were then sputtered with gold (Au). ZnO/Au nanostructures show excellent photocatalyst activities which were demonstrated by complete photodegradation of methylene blue (Mb) under UV irradiation and high decomposition rate k of 0.011 min-1.
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Relationships between social support characteristics with blood pressure control and recommended behaviors in Vietnamese hypertensive patients have not been investigated. This study is aimed at examining the role of social support characteristics in hypertension control and behaviors. Patients with hypertension (n = 220) in Hanoi, Vietnam, were recruited into a cross-sectional study. Both functional and structural characteristics of social support and network were examined. Results showed that increasing total network size was related to 52% higher odds of uncontrolled hypertension (adjusted OR = 1.52, 95%CI = 1.22 - 1.89). Higher network sizes on the provision of information support related to advice, emotional support related to decisions, and practical support related to sickness were associated with lower odds of uncontrolled hypertension. Every additional 1% of the percentage of network members having hypertension decreased 2% the odds of uncontrolled hypertension (adjusted OR = 0.98, 95%CI = 0.96 - 1.00). A 1% additional network members who were living in the same household was associated with a decrease of 0.08 point of behavioral adherence score (coef. = -0.08; 95%CI = -0.12 - 0.03). Meanwhile, a 1% increase of network members who were friends on the provision of practical support related to sickness and jobs was related to an increase of 0.10 point and 0.19 point of behavioral adherence score (coef. = 0.10; 95%CI = 0.04 - 0.17 and coef. = 0.19; 95%CI = 0.06 - 0.32, respectively). The current study suggested that further interventions to improve hypertension management should address the potential effects of social network characteristics.
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Pressão Sanguínea/fisiologia , Países em Desenvolvimento , Hipertensão/fisiopatologia , Pacientes Ambulatoriais , Apoio Social , Comportamento , Humanos , Pessoa de Meia-Idade , Rede SocialRESUMO
Type 2 diabetes (T2DM) epidemic is rising in Vietnam. Identifying associated factors with glycaemic control in patients with T2DM is vital to improve treatment outcomes. This study is aimed at examining the uncontrolled glycaemic level of patients with type 2 diabetes (T2DM) at an urban hospital in Hanoi, Vietnam, and determining associated factors. An observational longitudinal cohort survey was performed among T2DM patients. Glycaemic control was evaluated by using the HbA1c level ≥ 6.5% or fasting blood glucose level ≥ 7.5 g/mmol. Information about sociodemographic, clinical, and behavioral characteristics was collected. Multivariate mixed-effects logistic regression was employed to identify associated factors with control glycaemic level conditions. Among 189 T2DM patients, 70.4% had an uncontrolled glycaemic level. A higher number of comorbidities were associated with a lower likelihood of having uncontrolled glycaemic levels (OR = 0.71, p < 0.001, 95%CI = 0.52 - 0.98). Meanwhile, a higher body mass index (OR = 1.15, p < 0.05, 95%CI = 1.02 - 1.29), higher initial HbA1C (OR = 3.75, p < 0.01, 95%CI = 2.59 - 5.44), and higher initial fasting blood glucose levels (OR = 1.57, p < 0.01, 95%CI = 1.29 - 1.90) were positively associated with a higher risk of uncontrolled glycaemic levels. This study reveals that poor glycaemic control was common among T2DM patients in the urban hospital in Vietnam. Findings underlined the need for appropriate management strategies to control glycaemic levels and weight in this population.
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Diabetes Mellitus Tipo 2 , Controle Glicêmico , Hospitais Urbanos , Adulto , Idoso , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/terapia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , VietnãRESUMO
BACKGROUND: Visual search, an activity that relies on central vision, is frequent in daily life. This study investigates the effect of spacing between items in an object search task in participants with central vision loss. METHODS: Patients with neovascular age-related macular degeneration (AMD), age-matched controls, and young controls were included. The stimuli were displays of four, six and nine objects randomly presented in a 'crowded' (spacing 1.5°) or 'uncrowded' (spacing 6°) condition. For each of 96 trials, participants were asked to search for a predefined target that remained on the screen until the response was recorded. Accuracy, search time, and eye movements (number of fixations and scan path ratio) were recorded. RESULTS: Compared to older controls, accuracy decreased by 31 per cent and search time increased by 61 per cent in AMD participants. Ageing also affected performance with a lower accuracy by 13.5 per cent and longer search times by 46 per cent in older compared to younger controls. Increasing the spacing between elements increased accuracy by 21 per cent in AMD participants but it had no effect in older and younger controls. Performance was not related to visual acuity or to duration of neovascular AMD, but search time was correlated to the lesion size in the 'crowded' condition. CONCLUSIONS: Object search is ubiquitous in daily life activities. When visual acuity is irrevocably reduced, increasing the spacing between elements can reliably improve object search performance in patients.
Assuntos
Movimentos Oculares/fisiologia , Reconhecimento Visual de Modelos/fisiologia , Escotoma/fisiopatologia , Acuidade Visual , Campos Visuais/fisiologia , Degeneração Macular Exsudativa/fisiopatologia , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Escotoma/etiologia , Degeneração Macular Exsudativa/complicaçõesRESUMO
INTRODUCTION: The objective of the study is to report 4-year treatment outcome with intravitreal Aflibercept injections for neovascular age-related macular degeneration (nAMD) as first life therapy in real-life. Patients and Methods. This is a prospective, monocenter, observational case series analysis. Data from treatment-naïve patients with nAMD with at least 4 years of follow-up were included in the analysis. Data including age, gender, and visual acuity measured on Early Treatment of Diabetic Retinopathy Study charts (ETDRS) and injection numbers were recorded. Spectral domain optical coherence tomography (SD-OCT) data at baseline, month 3, month 6, month 12, year 2, 3, and 4 were also recorded. Patients were treated with a modified treat and extend (T&E) regimen. RESULTS: Of the 48 eyes with nAMD treated, only 31 eyes were available at the 4-year follow-up. The mean age was 81 ± 8 years. The VA gain was 7.3 ± 12.7 letters at 1 year 6.5 ± 12.5 letters at 2 years, VA gain 5.2 ± 17 letters at 3 years, and 6.2 ± 18.6 letters at 4 years. The reduction of central retinal thickness was 118 ± 187 µm at 4 years. Complete resolution of fluid was obtained in 18/31 eyes. The total number of injections was 5.7 ± 2.0 during the first year, 2.9 ± 2.9 during the second year, 3.5 ± 3.3 during the third year, and 4.0 ± 3.4 during the fourth year. The total number of injections was 16 ± 10.6, ranging from 3 to 52 injections. Ten eyes developed macular atrophy over the 4-year period. CONCLUSION: The results suggest that good long-term morphological and functional outcome can be achieved using Aflibercept in clinical setting.