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1.
Ophthalmology ; 122(10): 2053-62, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26253372

RESUMEN

PURPOSE: We investigate whether ocular and person-based characteristics were associated with dark adaptation (DA). DESIGN: Cross-sectional, single-center, observational study. PARTICIPANTS: One hundred sixteen participants older than 50 years of age with a range of age-related macular degeneration (AMD) severity. METHODS: Participants underwent best-corrected visual acuity (BCVA) testing, ophthalmoscopic examination, and multimodal imaging. Presence of reticular pseudodrusen (RPD) was assessed by masked grading of fundus images and was confirmed with optical coherence tomography. Eyes also were graded for AMD features (drusen, pigmentary changes, late AMD) to generate person-based AMD severity groups. One eye was designated the study eye for DA testing. Nonparametric statistical testing was performed on all comparisons. MAIN OUTCOME MEASURES: The primary outcome of this study was the rod intercept time (RIT), which is defined as the time for a participant's visual sensitivity to recover to a stimulus intensity of 5×10(-3) cd/m(2) (a decrease of 3 log units), or until a maximum test duration of 40 minutes was reached. RESULTS: A total of 116 study eyes from 116 participants (mean age, 75.4±9.4 years; 58% female) were analyzed. Increased RIT was associated significantly with increasing AMD severity, increasing age (r = 0.34; P = 0.0002), decreasing BCVA (r = -0.54; P < 0.0001), pseudophakia (P = 0.03), and decreasing subfoveal choroidal thickness (r = -0.27; P = 0.003). Study eyes with RPD (15/116 [13%]) had a significantly greater mean RIT compared with eyes without RPD in any AMD severity group (P < 0.02 for all comparisons), with 80% reaching the DA test ceiling. CONCLUSIONS: Impairments in DA increased with age, worse visual acuity, presence of RPD, AMD severity, and decreased subfoveal choroidal thickness. Analysis of covariance found the multivariate model that best fit the data included age, AMD group, and presence of RPD (R(2) = 0.56), with the presence of RPD conferring the largest parameter estimate.


Asunto(s)
Adaptación a la Oscuridad/fisiología , Degeneración Macular/fisiopatología , Drusas Retinianas/fisiopatología , Trastornos de la Visión/fisiopatología , Anciano , Anciano de 80 o más Años , Estudios Transversales , Femenino , Humanos , Degeneración Macular/diagnóstico , Masculino , Persona de Mediana Edad , Imagen Multimodal , Oftalmoscopía , Drusas Retinianas/diagnóstico , Índice de Severidad de la Enfermedad , Trastornos de la Visión/diagnóstico , Agudeza Visual/fisiología
2.
J Ophthalmol ; 2014: 726760, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25143829

RESUMEN

Purpose. To determine the prevalence of certain risk factors for glaucoma in a healthy, young population and to compare these risk factors between Asian Americans and Caucasians. Methods. 120 healthy graduate students (mean age 24.8 ± 3.0 years) underwent a comprehensive ophthalmic examination. Regression analyses controlling for age, sex, and refraction, comparing glaucoma risk factors in Asians (n = 54) and Caucasians (n = 41), were performed. Outcome variables included family history, intraocular pressure (IOP), spherical equivalent, central corneal thickness (CCT), mean deviation (MD) and pattern standard deviation (PSD), and disc and retinal nerve fiber layer (RNFL) parameters. Results. 61% of subjects were female; the mean spherical equivalent was -3.81 ± 3.2 D; and the mean axial length (AL) was 25.1 ± 1.7 mm. Regression analysis showed race affected spherical equivalent (P < 0.001), AL (P = 0.0073), IOP (P < 0.001), and cup to disc area ratio (CDAR) (P = 0.012). Family history, CCT, MD, and PSD did not vary between Asians and Caucasians (P > 0.05). In this study, we found Asian Americans, compared to Caucasians, had 2.95 ± 0.64 D greater myopia; greater IOP by 2.74 ± 0.62 mmHg; and larger CDAR by 0.12 ± 0.046. Conclusions. In our study population, young, healthy Asian Americans had greater myopia, IOP, and CDAR as compared to Caucasians, suggesting that racial variations can be important when diagnosing glaucoma.

4.
Am J Ophthalmol ; 156(6): 1159-1168.e4, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24012100

RESUMEN

PURPOSE: To investigate the frequency and types of systemic findings in patients with apparently isolated uveal coloboma. DESIGN: Cross-sectional observational study. METHODS: setting: Single-center ophthalmic genetics clinic. study population: Ninety-nine patients with uveal coloboma seen at the National Eye Institute. observational procedure: Results of audiology testing, echocardiogram, brain magnetic resonance imaging, renal ultrasound, and total spine radiographs. main outcome measure: Prevalence of abnormal findings on systemic testing. RESULTS: Uveal coloboma affected only the anterior segment in 8 patients, only the posterior segment in 23 patients, and both anterior and posterior segments in 68 patients. Best-corrected visual acuity (BCVA) of eyes with coloboma was ≥20/40 in 45% of eyes; 23% of eyes had BCVA of ≤20/400. The majority of patients (74%) had good vision (>20/60) in at least 1 eye. Ten of the 19 patients (53%) who underwent echocardiography had abnormalities, with ventral septal defects being the most prevalent. Abnormal findings were observed in 5 of 72 patients (7%) who had a renal ultrasound and in 5 of 29 patients (17%) who underwent a brain MRI. Audiology testing revealed abnormalities in 13 of 75 patients (17%), and spine radiographs showed anomalies in 10 of 77 patients (13%). Most findings required no acute intervention. CONCLUSIONS: Although some patients with coloboma had evidence of extraocular abnormalities, the majority of findings on routine clinical examination did not require acute intervention, but some warranted follow-up. Results from the systemic evaluation of patients with coloboma should be interpreted with caution and in view of their clinical context.


Asunto(s)
Anomalías Múltiples , Segmento Anterior del Ojo/anomalías , Coloboma/diagnóstico , Segmento Posterior del Ojo/anomalías , Anomalías Múltiples/diagnóstico , Adolescente , Adulto , Segmento Anterior del Ojo/patología , Encéfalo/anomalías , Niño , Preescolar , Estudios Transversales , Electrocardiografía , Femenino , Trastornos de la Audición/diagnóstico , Pruebas Auditivas , Cardiopatías Congénitas/diagnóstico , Humanos , Lactante , Riñón/anomalías , Imagen por Resonancia Magnética , Masculino , Microftalmía/diagnóstico , Fenotipo , Segmento Posterior del Ojo/patología , Columna Vertebral/anomalías , Agudeza Visual/fisiología , Adulto Joven
5.
Cornea ; 31(8): 959-62, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22406947

RESUMEN

PURPOSE: To describe a new surgical technique for the repair of conjunctivochalasis (CCh) using subconjunctival injection of fibrin sealant followed by conjunctival resection and to present a case series demonstrating our experience with the paste-pinch-cut technique. METHODS: A total of 139 eyes of 70 patients (43 women, 27 men) with CCh unresponsive to medical therapy received the described surgical treatment. The procedure consists of 3 primary steps-paste: fibrin sealant is injected subconjunctivally in a line inferior to the limbus; pinch: the conjunctiva is grasped with curved ptosis forceps, gathering the excess conjunctiva into a ridge, which is held, allowing the sealant to polymerize; and cut: the ridge of excess conjunctiva and sealant is resected. Subjective symptoms were assessed after surgery. RESULTS: Conjunctival redundancy was absent postoperatively in all eyes, resulting in a smooth conjunctival surface and restored tear meniscus. At the 3-month follow-up visit, 91.4% of patients reported improvement in symptoms. There were no recurrences or significant complications. CONCLUSIONS: The present retrospective, noncomparative, consecutive, interventional case series study introduces paste-pinch-cut conjunctivoplasty as a simple and an effective surgical treatment for the repair of CCh in symptomatic patients.


Asunto(s)
Conjuntiva/cirugía , Enfermedades de la Conjuntiva/cirugía , Adhesivo de Tejido de Fibrina/administración & dosificación , Procedimientos Quirúrgicos Oftalmológicos , Adhesivos Tisulares/administración & dosificación , Anciano , Anciano de 80 o más Años , Conjuntiva/efectos de los fármacos , Femenino , Humanos , Inyecciones Intraoculares , Masculino , Estudios Retrospectivos , Resultado del Tratamiento
6.
Stem Cells Dev ; 19(8): 1231-40, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19811096

RESUMEN

Human induced pluripotent stem cells (iPSCs) hold promise as a source of adult-derived, patient-specific pluripotent cells for use in cell-based regenerative therapies. However, current methods of cell culture are tedious and expensive, and the mechanisms underlying cell proliferation are not understood. In this study, we investigated expression and function of iPSC integrin extracellular matrix receptors to better understand the molecular mechanisms of cell adhesion, survival, and proliferation. We show that iPSC lines generated using Oct-3/4, Sox-2, Nanog, and Lin-28 express a repertoire of integrins similar to that of hESCs, with prominent expression of subunits alpha5, alpha6, alphav, beta1, and beta5. Integrin function was investigated in iPSCs cultured without feeder layers on Matrigel or vitronectin, in comparison to human embryonic stem cells. beta1 integrins were required for adhesion and proliferation on Matrigel, as shown by immunological blockade experiments. On vitronectin, the integrin alphavbeta5 was required for initial attachment, but inhibition of both alphavbeta5 and beta1 was required to significantly decrease iPSC proliferation. Furthermore, iPSCs cultured on vitronectin for 9 passages retained normal karyotype, pluripotency marker expression, and capacity to differentiate in vitro. These studies suggest that vitronectin, or derivatives thereof, might substitute for Matrigel in a more defined system for iPSC culture.


Asunto(s)
Proliferación Celular , Células Madre Pluripotentes Inducidas/citología , Células Madre Pluripotentes Inducidas/metabolismo , Integrinas/metabolismo , Anticuerpos Monoclonales/inmunología , Anticuerpos Monoclonales/farmacología , Antígenos de Diferenciación/metabolismo , Adhesión Celular/efectos de los fármacos , Adhesión Celular/fisiología , Técnicas de Cultivo de Célula , Diferenciación Celular/fisiología , Línea Celular , Colágeno/metabolismo , Combinación de Medicamentos , Células Madre Embrionarias/citología , Células Madre Embrionarias/metabolismo , Humanos , Integrina beta1/inmunología , Integrina beta1/metabolismo , Integrinas/genética , Cariotipificación , Laminina/metabolismo , Proteoglicanos/metabolismo , Receptores de Vitronectina/inmunología , Receptores de Vitronectina/metabolismo , Vitronectina/metabolismo
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