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2.
Sci Rep ; 9(1): 3482, 2019 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-30837658

RESUMO

Injury to retinal ganglion cells (RGC), central nervous system neurons that relay visual information to the brain, often leads to RGC axon degeneration and permanently lost visual function. Herein this study shows matrix-bound nanovesicles (MBV), a distinct class of extracellular nanovesicle localized specifically to the extracellular matrix (ECM) of healthy tissues, can neuroprotect RGCs and preserve visual function after severe, intraocular pressure (IOP) induced ischemia in rat. Intravitreal MBV injections attenuated IOP-induced RGC axon degeneration and death, protected RGC axon connectivity to visual nuclei in the brain, and prevented loss in retinal function as shown by histology, anterograde axon tracing, manganese-enhanced magnetic resonance imaging, and electroretinography. In the optic nerve, MBV also prevented IOP-induced decreases in growth associated protein-43 and IOP-induced increases in glial fibrillary acidic protein. In vitro studies showed MBV suppressed pro-inflammatory signaling by activated microglia and astrocytes, stimulated RGC neurite growth, and neuroprotected RGCs from neurotoxic media conditioned by pro-inflammatory astrocytes. Thus, MBV can positively modulate distinct signaling pathways (e.g., inflammation, cell death, and axon growth) in diverse cell types. Since MBV are naturally derived, bioactive factors present in numerous FDA approved devices, MBV may be readily useful, not only experimentally, but also clinically as immunomodulatory, neuroprotective factors for treating trauma or disease in the retina as well as other CNS tissues.


Assuntos
Apoptose , Axônios/metabolismo , Vesículas Extracelulares/química , Fármacos Neuroprotetores/química , Células Ganglionares da Retina/metabolismo , Animais , Apoptose/efeitos dos fármacos , Modelos Animais de Doenças , Vesículas Extracelulares/transplante , Proteína GAP-43/metabolismo , Proteína Glial Fibrilar Ácida/metabolismo , Interleucina-1beta/metabolismo , Pressão Intraocular/efeitos dos fármacos , Isquemia/metabolismo , Isquemia/patologia , Lipopolissacarídeos/farmacologia , Manganês/química , Microglia/citologia , Microglia/efeitos dos fármacos , Microglia/metabolismo , Crescimento Neuronal/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Nervo Óptico/metabolismo , Nervo Óptico/patologia , Ratos , Ratos Sprague-Dawley , Retina/metabolismo , Retina/patologia , Suínos
3.
J AAPOS ; 18(4): 396-8, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25173906

RESUMO

A 14-year-old African American girl presented with diminished vision in both eyes 1 week after undergoing an oophorectomy for a right ovarian mass. Systemic metastatic work-up was negative. Visual acuity was 20/40 in the right eye and 20/50 in the left eye. Slit-lamp biomicroscopy was unremarkable in both eyes. Fundus examination showed diffuse patchy areas of retinal pigment epithelial atrophy in the macula and peripheral retina bilaterally. Color vision had decreased in each eye. Electroretinography revealed nondetectable rod and cone responses. Both pattern and flash visual evoked potential (VEP) testing showed delayed latency in both eyes. She was treated with pulse intravenous methylprednisolone for 3 days along with intravenous immunoglobulins and rituximab, followed by systemic prednisolone and biweekly intravenous immunoglobulins and rituximab for 3 months. Antiretinal autoantibodies against 48-kDa (arrestin) and 64-kDa and 94-kDa proteins were positive, suggestive of carcinoma-associated retinopathy. After 3 months, visual acuity was 20/40 in each eye with improvement in color vision and VEP findings.


Assuntos
Neoplasias Ovarianas/patologia , Síndromes Paraneoplásicas Oculares/diagnóstico , Teratoma/patologia , Adolescente , Anticorpos Monoclonais Murinos/uso terapêutico , Antineoplásicos/uso terapêutico , Arrestina/imunologia , Autoanticorpos/sangue , Autoantígenos/imunologia , Defeitos da Visão Cromática , Quimioterapia Combinada , Eletrorretinografia , Potenciais Evocados Visuais , Feminino , Angiofluoresceinografia , Glucocorticoides/uso terapêutico , Humanos , Imunoglobulinas Intravenosas/uso terapêutico , Fatores Imunológicos/uso terapêutico , Metilprednisolona/uso terapêutico , Neoplasias Ovarianas/cirurgia , Ovariectomia , Síndromes Paraneoplásicas Oculares/tratamento farmacológico , Prednisolona/uso terapêutico , Rituximab , Teratoma/cirurgia , Tomografia de Coerência Óptica , Acuidade Visual
4.
Invest Ophthalmol Vis Sci ; 52(12): 8724-31, 2011 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-22003105

RESUMO

PURPOSE: Nystagmus eye movement data from infants and young children are often not suitable for advanced quantitative analysis. A method was developed to capture useful information from noisy data and validate the technique by showing meaningful relationships with visual functioning. METHODS: Horizontal eye movements from patients (age 5 months-8 years) with idiopathic infantile nystagmus syndrome (INS) were used to develop a quantitative outcome measure that allowed for head and body movement during the recording. The validity of this outcome was assessed by evaluating its relation to visual acuity deficit in 130 subjects, its relation to actual fixation as assessed under simultaneous fundus imaging, its correlation with the established expanded nystagmus acuity function (NAFX), and its test-retest variability. RESULTS: The nystagmus optimal fixation function (NOFF) was defined as the logit transform of the fraction of data points meeting position and velocity criteria within a moving window. A decreasing exponential relationship was found between visual acuity deficit and the NOFF, yielding a 0.75 logMAR deficit for the poorest NOFF and diminishing deficits with improving foveation. As much as 96% of the points identified as foveation events fell within 0.25° of the actual target. Good correlation (r = 0.96) was found between NOFF and NAFX. Test-retest variability was 0.49 logit units. CONCLUSIONS: The NOFF is a feasible method to quantify noisy nystagmus eye movement data. Its validation makes it a promising outcome measure for the progression and treatment of nystagmus during early childhood.


Assuntos
Técnicas de Diagnóstico Oftalmológico/normas , Nistagmo Congênito/diagnóstico , Nistagmo Congênito/fisiopatologia , Índice de Gravidade de Doença , Transtornos da Visão/diagnóstico , Acuidade Visual/fisiologia , Adolescente , Adulto , Algoritmos , Criança , Pré-Escolar , Progressão da Doença , Estudos de Viabilidade , Feminino , Fixação Ocular/fisiologia , Fóvea Central/fisiopatologia , Humanos , Lactente , Masculino , Modelos Biológicos , Transtornos da Visão/fisiopatologia , Adulto Jovem
5.
Invest Ophthalmol Vis Sci ; 52(3): 1404-11, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21071734

RESUMO

PURPOSE: Infantile nystagmus syndrome (INS) can be idiopathic or associated with ocular or systemic disease. The ocular oscillation of INS directly contributes to loss of visual acuity. In this study, visual acuity development in patients with INS was examined. METHODS: Children with INS were classified as having idiopathic INS (n = 84) or INS with an associated sensory deficit: INS and albinism (n = 71), bilateral optic nerve hypoplasia (ONH; n = 23), or congenital retinal disorder (n = 36). Visual acuity was assessed with Teller cards and/or optotypes, and the data were analyzed for three age groups (<24 months, 24-48 months, and >48 months). RESULTS: Patients with idiopathic INS showed mildly reduced visual acuity early in life and gradual maturation with age that paralleled a normative curve. Patients with albinism also showed a mild visual deficit early in life but failed to keep pace with the normative curve, showing a gradual increase in visual acuity deficit. Patients with ONH and congenital retinal disorders exhibited more severe visual acuity deficits during infancy. The ONH group displayed slow improvement of visual acuity with a plateau at 24 months through >48 months, with a small increase in visual acuity deficit. The congenital retinal disorder group had no significant change in visual acuity across age and had a rapid increase in visual acuity deficit. CONCLUSIONS: The pattern of visual acuity development differs among children with INS, depending on the presence or absence of associated sensory system deficits. Careful characterization of visual system differences in patients with INS is important if visual acuity is an outcome in clinical trials.


Assuntos
Nistagmo Congênito/fisiopatologia , Transtornos da Visão/fisiopatologia , Acuidade Visual/fisiologia , Criança , Pré-Escolar , Estudos Transversais , Humanos , Lactente , Síndrome , Testes Visuais
6.
Am J Clin Nutr ; 91(4): 848-59, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20130095

RESUMO

BACKGROUND: The range of human milk docosahexaenoic acid (DHA) concentrations worldwide is much broader than the range explored in randomized clinical trials to date. OBJECTIVE: The primary objective was to determine the effect of 4 amounts of DHA supplementation on the visual acuity of formula-fed infants at 12 mo of age. Secondary objectives were to evaluate visual acuity maturation, red blood cell fatty acids, tolerance, anthropometric measures, and adverse events. DESIGN: This double-masked, randomized trial was conducted at 2 sites (Dallas and Kansas City). Three hundred forty-three healthy, term, formula-fed infants were enrolled at 1-9 d of age and were randomly assigned to be fed 1 of the following 4 infant formulas containing equivalent nutrient amounts, except for long-chain polyunsaturated fatty acids: control (0% DHA), 0.32% DHA, 0.64% DHA, or 0.96% DHA; DHA-supplemented formulas also provided 0.64% arachidonic acid. Visual acuity was measured by visual evoked potentials in 244 infants who completed the 12-mo primary outcome examination. RESULTS: Infants fed control formula had significantly poorer visual evoked potential visual acuity at 12 mo of age than did infants who received any of the DHA-supplemented formulas (P < 0.001). There were no significant differences in visual evoked potential visual acuity between the 3 amounts of DHA supplementation for either site at any age tested. CONCLUSIONS: DHA supplementation of infant formula at 0.32% of total fatty acids improves visual acuity. Higher amounts of DHA supplementation were not associated with additional improvement of visual acuity. This trial was registered at clinicaltrials.gov as NCT00753818.


Assuntos
Gorduras na Dieta/administração & dosagem , Ácidos Docosa-Hexaenoicos/farmacologia , Potenciais Evocados Visuais/efeitos dos fármacos , Recém-Nascido/crescimento & desenvolvimento , Neurogênese/efeitos dos fármacos , Visão Ocular/efeitos dos fármacos , Acuidade Visual/efeitos dos fármacos , Ácido Araquidônico/administração & dosagem , Dieta , Ácidos Docosa-Hexaenoicos/administração & dosagem , Método Duplo-Cego , Feminino , Humanos , Fórmulas Infantis , Recém-Nascido/fisiologia , Masculino , Estados Unidos , Visão Ocular/fisiologia , Acuidade Visual/fisiologia
7.
Invest Ophthalmol Vis Sci ; 48(2): 661-4, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17251463

RESUMO

PURPOSE: Esotropia (ET) in infancy may initially manifest as a small-angle, variable-angle, or intermittent deviation. Some patients experience spontaneous resolution and become orthophoric. Others progress to constant large-angle ET and require surgery. The authors examined factors that may be associated with risk for progression to constant large-angle ET. METHODS: Seventy-seven infants who initially presented with intermittent, small (<20 prism diopter [pd]) or variable-angle ET at 2 to 12 months of age were followed up until the ET was resolved, the infants had surgery, or the parents or guardians refused surgery. All infants with refractive correction >/=+3.50 D were treated initially with glasses. Four risk factors were examined: prescription of occlusion therapy, initial visit before 6 months of age, presence of amblyopia, and abnormal stereoacuity. RESULTS: All 12 infants with small or variable angles progressed to constant large-angle ET and surgery. ET resolved spontaneously in 44.6% (29/65) infants in whom it was intermittent. Infants with intermittent ET who received patches as initial treatment and who had abnormal stereoacuity had 3.4x (95% confidence interval [CI], 1.83-6.29) and 3.4x (95% CI, 1.66-6.78) higher risk for progression to constant large-angle ET, respectively. Neither age at initial visit nor amblyopia presented risk for progression. CONCLUSIONS: Abnormal stereoacuity and occlusion therapy pose significant risks for progression from intermittent to constant large-angle ET. Intermittent ET that develops during the first year of life has a high likelihood of spontaneous resolution, whereas constant small-angle or variable-angle ET seldom resolves.


Assuntos
Esotropia/fisiopatologia , Músculos Oculomotores/fisiopatologia , Progressão da Doença , Esotropia/terapia , Óculos , Seguimentos , Humanos , Lactente , Procedimentos Cirúrgicos Oftalmológicos , Remissão Espontânea , Fatores de Risco , Privação Sensorial , Acuidade Visual
8.
J AAPOS ; 10(5): 419-23, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17070476

RESUMO

PURPOSE: We sought to develop a new "Distance Randot" test, establish a normative data set for children and adults, and compare with established measures of stereoacuity. METHODS: Distance Randot, distance Frisby-Davis 2 (FD2), and near Preschool Randot stereoacuity (Stereo Optical Co., Inc., Chicago, IL) were assessed in 23 normal children (ages 4-14 years), 21 normal adults (ages 20-36 years), and 131 patients with a variety of strabismic conditions (ages 4-85 years). For each test, stereoacuity was defined as the smallest disparity in which 2 targets were correctly identified. The simultaneous prism and cover test (SPCT) and the alternate prism and cover test (APCT) were used to assess misalignment. RESULTS: For the new Distance Randot test, normative results were similar to published data obtained with established near and distance stereoacuity tests. In the patient cohort, comparing stereoacuity data obtained from Distance Randot stereoacuity test and the Near Preschool Randot stereoacuity test, most of the patients with discordant scores had poorer distance than near stereoacuity. Comparing the Distance Randot stereoacuity test and the Distance FD2, all of the patients with discordant scores had poorer Distance Randot than FD2 scores. CONCLUSIONS: Distance Randot test is more likely to detect abnormalities in distance stereopsis and may provide a useful tool in measuring distance stereoacuity in patients with and without strabismus. However, further studies are needed to define the efficacy of the Distance Randot test in monitoring progression specific conditions such as intermittent exotropia, where it may prove useful as a guide to the timing of intervention.


Assuntos
Percepção de Profundidade/fisiologia , Testes Visuais/instrumentação , Acuidade Visual/fisiologia , Adolescente , Adulto , Criança , Pré-Escolar , Humanos , Valores de Referência , Sensibilidade e Especificidade , Estrabismo/fisiopatologia , Visão Binocular/fisiologia
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