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1.
Exp Eye Res ; 192: 107938, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31972211

RESUMO

Retinal ganglion cell (RGC) degeneration, leading to irreversible blindness in chronic optic neuropathies, commonly begins with dendritic shrinkage followed by axon degeneration. Although limited axon regeneration in the optic nerve is possible with a genetic deletion of PTEN/SOCS3 after optic nerve injury, the roles of PTEN/SOCS3 on dendritic preservation and regeneration remain unclear. This study investigated the effect of PTEN/SOCS3 genetic deletion on the structural integrity of RGC dendrites and axons in the retina following optic nerve crush. Using time-lapse, in vivo confocal scanning laser ophthalmoscopy to serially image dendritic and axonal arborizations of RGCs over six months after injury, RGC dendrites and axons were only preserved in Thy-1-YFP/PTEN-/- and Thy-1-YFP/PTEN-/-SOCS3-/- mice, and axons in the retina regenerated at a rate of 21.1 µm/day and 15.5 µm/day, respectively. By contrast, dendritic complexity significantly decreased in Thy-1-YFP-SOCS3-/- and control mice at a rate of 7.0 %/day and 7.1 %/day, respectively, and no axon regeneration in the retina was observed. RGC survival probability was higher in Thy-1-YFP/PTEN-/- and Thy-1-YFP/PTEN-/-SOCS3-/- mice compared with Thy-1-YFP-SOCS3-/- and control mice. The differential responses between the transgenic mice demonstrate that although a genetic deletion of PTEN, SOCS3, or PTEN/SOCS3 allows partial axon regeneration in the optic nerve after optic nerve crush, a deletion of PTEN, but not SOCS3, ameliorates RGC dendritic shrinkage. This shows that the signaling pathways involved in promoting axon regeneration do not equally contribute to the preservation of dendrites, which is crucial to the translational application of neuroregenerative therapies for visual restoration.


Assuntos
Dendritos/fisiologia , Deleção de Genes , Fibras Nervosas/fisiologia , Traumatismos do Nervo Óptico/fisiopatologia , PTEN Fosfo-Hidrolase/genética , Células Ganglionares da Retina/fisiologia , Proteína 3 Supressora da Sinalização de Citocinas/genética , Animais , Dependovirus/genética , Feminino , Vetores Genéticos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Microscopia Confocal , Compressão Nervosa , Regeneração Nervosa/fisiologia
2.
Gene Ther ; 26(3-4): 109-120, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30692605

RESUMO

Efficient transduction of the retinal ganglion cells (RGCs) is a prerequisite to maximize therapeutic outcomes in any form of gene therapy for optic neuropathies. Whereas subretinal injection of adeno-associated virus 2 (AAV2) has been well-characterized, the serotype, viral load, and promoter combinations that govern RGC transduction efficiency following intravitreal injection remains poorly understood. We evaluated the transduction efficiency of seven AAV2 serotypes (AAV2/1, AAV2/2, AAV2/4, AAV2/5, AAV2/6, AAV2/8, and AAV2/9) for the RGCs at 4 weeks following intravitreal injection in C57BL/6J mice. Intravitreal injection of 1 × 109 vg of AAV2/2 with eGFP driven by the CMV promoter attained a higher transduction efficiency for the RGCs (60.0 ± 4.2%) compared with the six other AAV2 serotypes with eGFP driven by the same promoter injected at the same viral load ( < 3.0%). Reporter driven by the CAG promoter had a lower transduction efficiency (up to 42.0 ± 5.8%) compared with that driven by the CMV reporter (60.0 ± 4.2%, p ≤ 0.024). There was a viral dose-dependent transduction effect of AAV2/2-CMV-eGFP and the transduction efficiency was 40.2 ± 3.9%, 16.6 ± 4.2%, and 2.6 ± 0.2% when the viral load decreased to 5 × 108 vg, 1 × 108 vg, and 1 × 107 vg, respectively. Optimizing viral serotype, viral load, and promoter construct of AAV2 is important to maximize transgene expression in RGC-targeted gene therapy.


Assuntos
Terapia Genética/métodos , Células Ganglionares da Retina/efeitos dos fármacos , Transdução Genética/métodos , Animais , Dependovirus , Vetores Genéticos/genética , Proteínas de Fluorescência Verde/genética , Injeções Intravítreas , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Parvovirinae/genética , Retina/metabolismo , Células Ganglionares da Retina/metabolismo
3.
Ophthalmology ; 120(12): 2517-2524, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23850092

RESUMO

OBJECTIVE: To measure iris volume and anterior segment parameters using a swept-source anterior segment optical coherence tomography (OCT) and investigate factors associated with iris volume and iris volume change after pupil dilation in eyes with open angles and angle closure. DESIGN: Cross-sectional study. PARTICIPANTS: A total of 86 eyes, including 31 eyes from 21 patients with primary angle closure (PAC) or PAC suspect, 31 eyes from 20 patients with primary open-angle glaucoma (POAG), and 24 eyes from 15 normal subjects, were included. METHODS: The anterior segment parameters and iris were imaged and measured by the Casia SS-1000 OCT (Tomey, Nagoya, Japan) in room light, dark, and after pharmacologic dilation. Linear mixed models were used to examine the association between iris volume and change in iris volume after dilation and each of the following: age, sex, anterior chamber volume (ACV), axial length, pupil diameter, and angle width. MAIN OUTCOME MEASURES: Iris volume. RESULTS: The mean iris volume significantly decreased from light to dark and after pharmacologic dilation in angle closure (40.0 ± 5.2, 38.8 ± 5.4, and 32.5 ± 4.5 mm(3), respectively), POAG (40.2 ± 5.3, 39.4 ± 5.4, and 33.6 ± 4.2 mm(3), respectively), and normal eyes (40.1 ± 4.2, 39.1 ± 3.9, and 33.0 ± 4.4 mm(3), respectively). From room light to dark, the iris volume of 16.7% normal, 19.4% POAG, and 19.4% angle closure eyes increased iris volume (P = 0.960). After pharmacologic dilation, iris volume decreased in all eyes. Iris volume was negatively associated with ACV and positively associated with axial length (P<0.001). The change in iris volume per millimeter change in pupil diameter was 2.11, 2.01, and 1.80 mm(3)/mm in the angle closure, POAG, and normal groups, respectively (P≥0.414). A smaller ACV (P = 0.049) and older age (P = 0.036) were associated with a smaller change in iris volume per millimeter change in pupil diameter. A larger iris volume, smaller ACV, and greater pupil diameter were significant determinants of a smaller angle width (all P≤0.003). CONCLUSIONS: The mean iris volume decreased after pupil dilation in open-angle and angle closure eyes, and the degree of reduction was less in eyes with a smaller ACV. Both iris volume and ACV were important determinants of the anterior chamber angle.


Assuntos
Glaucoma de Ângulo Fechado/patologia , Iris/patologia , Tomografia de Coerência Óptica , Idoso , Segmento Anterior do Olho/patologia , Visão de Cores , Estudos Transversais , Combinação de Medicamentos , Feminino , Glaucoma de Ângulo Aberto/patologia , Humanos , Pressão Intraocular , Masculino , Pessoa de Meia-Idade , Midriáticos/administração & dosagem , Visão Noturna , Variações Dependentes do Observador , Fenilefrina/administração & dosagem , Pupila/efeitos dos fármacos , Reprodutibilidade dos Testes , Tonometria Ocular , Tropicamida/administração & dosagem
4.
Ophthalmology ; 120(6): 1144-9, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23522970

RESUMO

OBJECTIVE: To investigate the use of swept-source optical coherence tomography (OCT) for measuring the area and degree of peripheral anterior synechia (PAS) involvement in patients with angle-closure glaucoma. DESIGN: Cross-sectional study. PARTICIPANTS: Twenty-three eyes with PAS (detected by indentation gonioscopy) from 20 patients with angle-closure glaucoma (20 eyes had primary angle-closure glaucoma and 3 eyes had angle-closure glaucoma secondary to chronic anterior uveitis [n = 2] and Axenfeld-Rieger syndrome [n = 1]). METHODS: The anterior chamber angles were evaluated with indentation gonioscopy and imaged by swept-source OCT (Casia OCT, Tomey, Nagoya, Japan) in room light and in the dark using the "angle analysis" protocol, which was composed of 128 radial B-scans each with 512 A-scans (16-mm scan length). The area and degree of PAS involvement were measured in each eye after manual detection of the scleral spur and the anterior irido-angle adhesion by 2 masked observers. The interobserver variability of the PAS measurements was calculated. MAIN OUTCOME MEASURES: The agreement of PAS assessment by gonioscopy and OCT, the area and the degree of PAS involvement, and the intraclass correlation coefficient (ICC) of interobserver PAS measurements. RESULTS: The area of PAS (mean ± standard deviation) was 20.8 ± 16.9 mm(2) (range, 3.9-74.9 mm(2)), and the degree of PAS involvement was 186.5 ± 79.9 degrees (range, 42-314 degrees). There was no difference in the area of PAS (P = 0.90) and the degree of PAS involvement (P = 0.95) between images obtained in room light and in the dark. The interobserver ICCs were 0.99 (95% confidence interval [CI], 0.98-1.00) for the area of PAS and 0.99 (95% CI, 0.97-1.00) for the degree of PAS involvement. There was good agreement of PAS assessment between gonioscopy and OCT images (kappa = 0.79; 95% CI, 0.67-0.91). CONCLUSIONS: Swept-source OCT allows visualization and reproducible measurements of the area and degree of PAS involvement, providing a new paradigm for evaluation of PAS progression and risk assessment for development of angle-closure glaucoma. FINANCIAL DISCLOSURE(S): The author(s) have no proprietary or commercial interest in any materials discussed in this article.


Assuntos
Câmara Anterior/patologia , Glaucoma de Ângulo Fechado/diagnóstico , Doenças da Íris/diagnóstico , Tomografia de Coerência Óptica/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Segmento Anterior do Olho/anormalidades , Doença Crônica , Estudos Transversais , Anormalidades do Olho/complicações , Oftalmopatias Hereditárias , Feminino , Glaucoma de Ângulo Fechado/etiologia , Gonioscopia , Perda Auditiva Neurossensorial/complicações , Cardiopatias Congênitas/complicações , Humanos , Pressão Intraocular , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Aderências Teciduais/diagnóstico , Uveíte/complicações
5.
Light Sci Appl ; 12(1): 200, 2023 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-37607903

RESUMO

Resolving three-dimensional morphological features in thick specimens remains a significant challenge for label-free imaging. We report a new speckle diffraction tomography (SDT) approach that can image thick biological specimens with ~500 nm lateral resolution and ~1 µm axial resolution in a reflection geometry. In SDT, multiple-scattering background is rejected through spatiotemporal gating provided by dynamic speckle-field interferometry, while depth-resolved refractive index maps are reconstructed by developing a comprehensive inverse-scattering model that also considers specimen-induced aberrations. Benefiting from the high-resolution and full-field quantitative imaging capabilities of SDT, we successfully imaged red blood cells and quantified their membrane fluctuations behind a turbid medium with a thickness of 2.8 scattering mean-free paths. Most importantly, we performed volumetric imaging of cornea inside an ex vivo rat eye and quantified its optical properties, including the mapping of nanoscale topographic features of Dua's and Descemet's membranes that had not been previously visualized.

6.
Front Physiol ; 13: 893783, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35711313

RESUMO

The ideal exercise time of day (ETOD) remains elusive regarding simultaneous effects on health and performance outcomes, especially in women. Purpose: Given known sex differences in response to exercise training, this study quantified health and performance outcomes in separate cohorts of women and men adhering to different ETOD. Methods: Thirty exercise-trained women (BMI = 24 ± 3 kg/m2; 42 ± 8 years) and twenty-six men (BMI = 25.5 ± 3 kg/m2; 45 ± 8 years) were randomized to multimodal ETOD in the morning (0600-0800 h, AM) or evening (1830-2030 h, PM) for 12 weeks and analyzed as separate cohorts. Baseline (week 0) and post (week 12) muscular strength (1-RM bench/leg press), endurance (sit-ups/push-ups) and power (squat jumps, SJ; bench throws, BT), body composition (iDXA; fat mass, FM; abdominal fat, Abfat), systolic/diastolic blood pressure (BP), respiratory exchange ratio (RER), profile of mood states (POMS), and dietary intake were assessed. Results: Twenty-seven women and twenty men completed the 12-week intervention. No differences at baseline existed between groups (AM vs PM) for both women and men cohorts. In women, significant interactions (p < 0.05) existed for 1RM bench (8 ± 2 vs 12 ± 2, ∆kg), pushups (9 ± 1 vs 13 ± 2, ∆reps), BT (10 ± 6 vs 45 ± 28, ∆watts), SJ (135 ± 6 vs 39 ± 8, ∆watts), fat mass (-1.0 ± 0.2 vs -0.3 ± 0.2, ∆kg), Abfat (-2.6 ± 0.3 vs -0.9 ± 0.5, ∆kg), diastolic (-10 ± 1 vs-5 ± 5, ∆mmHg) and systolic (-12.5 ± 2.7 vs 2.3 ± 3, mmHg) BP, AM vs PM, respectively. In men, significant interactions (p < 0.05) existed for systolic BP (-3.5 ± 2.6 vs -14.9 ± 5.1, ∆mmHg), RER (-0.01 ± 0.01 vs -0.06 ± 0.01, ∆VCO2/VO2), and fatigue (-0.8 ± 2 vs -5.9 ± 2, ∆mm), AM vs PM, respectively. Macronutrient intake was similar among AM and PM groups. Conclusion: Morning exercise (AM) reduced abdominal fat and blood pressure and evening exercise (PM) enhanced muscular performance in the women cohort. In the men cohort, PM increased fat oxidation and reduced systolic BP and fatigue. Thus, ETOD may be important to optimize individual exercise-induced health and performance outcomes in physically active individuals and may be independent of macronutrient intake.

7.
JAMA Ophthalmol ; 138(5): 490-498, 2020 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-32191274

RESUMO

Importance: Clinical assessment of vision-related disability is hampered by the lack of instruments to assess visual performance in real-world situations. Interactive virtual reality (VR) environments displayed in a binocular stereoscopic VR headset have been designed, presumably simulating day-to-day activities to evaluate vision-related disability. Objective: To investigate the application of VR to identify vision-related disability in patients with glaucoma. Design, Setting, and Participants: In a cross-sectional study, 98 patients with glaucoma and 50 healthy individuals were consecutively recruited from a university eye clinic; all participants were Chinese. The study was conducted between August 30, 2016, and July 31, 2017; data analysis was performed from December 1, 2017, to October 30, 2018. Exposures: Measurements of visual acuity, contrast sensitivity, visual field (VF), National Eye Institute 25-item Visual Function Questionnaire Rasch score, and VR disability scores determined from 5 VR simulations: supermarket shopping, stair and city navigations in daytime, and stair and city navigations in nighttime. Duration required to complete the simulation, number of items incorrectly identified, and number of collisions were measured to compute task-specific and overall VR disability scores. Vision-related disability was identified when the VR disability score was outside the normal age-adjusted 95% confidence region. Main Outcomes and Measures: Virtual reality disability score. Results: In the 98 patients with glaucoma, mean (SD) age was 49.8 (11.6) years and 60 were men (61.2%); in the 50 healthy individuals, mean (SD) age was 48.3 (14.8) years and 16 were men (32.0%). The patients with glaucoma had different degrees of VF loss (122 eyes [62.2%] had moderate or advanced VF defects). The time required to complete the activities by patients with glaucoma vs healthy individuals was longer by 15.2 seconds (95% CI, 5.5-24.9 seconds) or 34.1% (95% CI, 12.4%-55.7%) for the shopping simulation, 72.8 seconds (95% CI, 23.0-122.6 seconds) or 33.8% (95% CI, 10.7%-56.9%) for the nighttime stair navigation, and 38.1 seconds (95% CI, 10.9-65.2 seconds) or 30.8% (95% CI, 8.8%-52.8%) for the nighttime city navigation. The mean (SD) duration was not significantly different between the glaucoma and healthy groups in daytime stair (203.7 [93.7] vs 192.9 [89.1] seconds, P = .52) and city (118.7 [41.5] vs 117.0 [52.3] seconds, P = .85) navigation. For each decibel decrease in binocular VF sensitivity, the risk of collision increased by 15% in nighttime stair (hazard ratio [HR], 1.15; 95% CI, 1.08-1.22) and city (HR, 1.15; 95% CI, 1.08-1.23) navigations. Fifty-eight patients (59.1%) with glaucoma had vision-related disability in at least 1 simulated daily task; a higher proportion of patients had vision-related disability in nighttime city (27 of 88 [30.7%]) and stair (27 of 90 [30.0%]) navigation than in daytime city (7 of 88 [8.0%]) and stair (19 of 96 [19.8%]) navigation. The overall VR disability score was associated with the National Eye Institute 25-item Visual Function Questionnaire Rasch score (R2 = 0.207). Conclusions and Relevance: These findings suggest that vision-related disability is associated with lighting condition and task in patients with glaucoma. Virtual reality may allow eye care professionals to understand the patients' perspectives on how visual impairment imparts disability in daily living and provide a new paradigm to augment the assessment of vision-related disability.


Assuntos
Avaliação da Deficiência , Glaucoma de Ângulo Fechado/diagnóstico , Glaucoma de Ângulo Aberto/diagnóstico , Realidade Virtual , Transtornos da Visão/diagnóstico , Atividades Cotidianas , Adulto , Idoso , Simulação por Computador , Estudos Transversais , Feminino , Glaucoma de Ângulo Fechado/fisiopatologia , Glaucoma de Ângulo Aberto/fisiopatologia , Humanos , Pressão Intraocular/fisiologia , Masculino , Pessoa de Meia-Idade , Perfil de Impacto da Doença , Inquéritos e Questionários , Transtornos da Visão/fisiopatologia , Visão Binocular/fisiologia , Acuidade Visual/fisiologia , Campos Visuais/fisiologia
8.
Mol Ther Nucleic Acids ; 21: 251-263, 2020 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-32599451

RESUMO

Irreversible blindness from glaucoma and optic neuropathies is attributed to retinal ganglion cells (RGCs) losing the ability to regenerate axons. While several transcription factors and proteins have demonstrated enhancement of axon regeneration after optic nerve injury, mechanisms contributing to the age-related decline in axon regenerative capacity remain elusive. In this study, we show that microRNAs are differentially expressed during RGC development and identify microRNA-19a (miR-19a) as a heterochronic marker; developmental decline of miR-19a relieves suppression of phosphatase and tensin homolog (PTEN), a key regulator of axon regeneration, and serves as a temporal indicator of decreasing axon regenerative capacity. Intravitreal injection of miR-19a promotes axon regeneration after optic nerve crush in adult mice, and it increases axon extension in RGCs isolated from aged human donors. This study uncovers a previously unrecognized involvement of the miR-19a-PTEN axis in RGC axon regeneration, and it demonstrates therapeutic potential of microRNA-mediated restoration of axon regenerative capacity in optic neuropathies.

9.
Sci Rep ; 9(1): 9057, 2019 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-31227762

RESUMO

Glaucoma is a leading cause of blindness characterized by progressive degeneration of retinal ganglion cells (RGCs). A well-established risk factor for the development and progression of glaucoma is elevation of intraocular pressure (IOP). However, how elevated IOP leads to RGC degeneration remains poorly understood. Here, we fabricate a facile, tunable hydrostatic pressure platform to study the effect of increased hydrostatic pressure on RGC axon and total neurite length, cell body area, dendritic branching, and cell survival. The hydrostatic pressure can be adjusted by varying the height of a liquid reservoir attached to a three-dimensional (3D)-printed adapter. The proposed platform enables long-term monitoring of primary RGCs in response to various pressure levels. Our results showed pressure-dependent changes in the axon length, and the total neurite length. The proportion of RGCs with neurite extensions significantly decreased by an average of 38 ± 2% (mean ± SEM) at pressures 30 mmHg and above (p < 0.05). The axon length and total neurite length decreased at a rate of 1.65 ± 0.18 µm and 4.07 ± 0.34 µm, respectively (p < 0.001), for each mmHg increase in pressure after 72 hours pressure treatment. Dendritic branching increased by 0.20 ± 0.05 intersections/day at pressures below 25 mmHg, and decreased by 0.07 ± 0.01 intersections/day at pressures above 25 mmHg (p < 0.001). There were no significant changes in cell body area under different levels of hydrostatic pressure (p ≥ 0.05). Application of this model will facilitate studies on the biophysical mechanisms that contribute to the pathophysiology of glaucoma and provide a channel for the screening of potential pharmacological agents for neuroprotection.


Assuntos
Células Ganglionares da Retina/fisiologia , Animais , Glaucoma/fisiopatologia , Pressão Hidrostática , Pressão Intraocular , Dispositivos Lab-On-A-Chip , Ratos , Ratos Sprague-Dawley , Tonometria Ocular
10.
Acta Biomater ; 94: 219-231, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31176841

RESUMO

Investigation of neurodegeneration in glaucoma, a leading cause of irreversible blindness worldwide, has been obfuscated by the lack of an efficient model that provides chronic, mild to moderate elevation of intraocular pressure (IOP) with preservation of optical media clarity for long term, in vivo interrogation of the structural and functional integrity of the retinal ganglion cells (RGCs). Here, we designed and formulated an injectable hydrogel based on in situ cross-linking of hyaluronic acid functionalized with vinyl sulfone (HA-VS) and thiol groups (HA-SH). Intracameral injection of HA-VS and HA-SH in C57BL/6J mice exhibited mild to moderate elevation of IOP with daily mean IOP ranged between 14 ±â€¯3 and 24 ±â€¯3 mmHg, which led to progressive, regional loss of RGCs evaluated with in vivo, time-lapse confocal scanning laser ophthalmoscopy; a reduction in fractional anisotropy in the optic nerve and the optic tract projected from the eye with increased IOP in diffusion tensor magnetic resonance imaging; a decrease in positive scotopic threshold response in electroretinography; and a decline in visual acuity measured with an optokinetic virtual reality system. The proportion of RGC loss was positively associated with the age of the animals, and the levels and the duration of IOP elevation. The new glaucoma model recapitulates key characteristics of human glaucoma which is pertinent to the development and pre-clinical testing of neuroprotective and neuroregenerative therapies. STATEMENT OF SIGNIFICANCE: A new model to study chronic neurodegeneration in glaucoma has been developed via intracameral injection of a specifically designed hyaluronic acid functionalized with vinyl sulfone and thiol groups for cross-linking. Intracameral injection of the chemically cross-linked hydrogel generates mild to moderate IOP elevation, resulting in progressive degeneration of the retinal ganglion cells, optic nerve, and optic tract, and a decline in visual function. The model recapitulates the key features of neurodegeneration in human glaucoma, which will facilitate and expedite the development of neuroprotective and neuroregenerative therapies.


Assuntos
Reagentes de Ligações Cruzadas/química , Glaucoma/metabolismo , Ácido Hialurônico/química , Hidrogéis/química , Doenças Neurodegenerativas/metabolismo , Fatores Etários , Animais , Modelos Animais de Doenças , Elasticidade , Eletrorretinografia , Hidrogéis/administração & dosagem , Hidrogéis/metabolismo , Injeções , Injeções Intraoculares , Pressão Intraocular/efeitos dos fármacos , Cinética , Imageamento por Ressonância Magnética , Camundongos Endogâmicos C57BL , Doenças Neurodegenerativas/complicações , Nervo Óptico/efeitos dos fármacos , Células Ganglionares da Retina/efeitos dos fármacos , Compostos de Sulfidrila/química , Sulfonas/química , Viscosidade
11.
Stem Cells Dev ; 28(20): 1365-1375, 2019 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-31580778

RESUMO

Glaucoma is characterized by retinal ganglion cell (RGC) degeneration and is the second leading cause of blindness worldwide. However, current treatments such as eye drop or surgery have limitations and do not target the loss of RGC. Regenerative therapy using embryonic stem cells (ESCs) holds a promising option, but ethical concern hinders clinical applications on human subjects. In this study, we employed spermatogonial stem cells (SSCs) as an alternative source of ESCs for cell-based regenerative therapy in mouse glaucoma model. We generated functional RGCs from SSCs with a two-step protocol without applying viral transfection or chemical induction. SSCs were first dedifferentiated to embryonic stem-like cells (SSC-ESCs) that resemble ESCs in morphology, gene expression signatures, and stem cell properties. The SSC-ESCs then differentiated toward retinal lineages. We showed SSC-ESC-derived retinal cells expressed RGC-specific marker Brn3b and functioned as bona fide RGCs. To allow in vivo RGC tracing, Brn3b-EGFP reporter SSC-ESCs were generated and the derived RGCs were subsequently transplanted into the retina of glaucoma mouse models by intravitreal injection. We demonstrated that the transplanted RGCs could survive in host retina for at least 10 days after transplantation. SSC-ESC-derived RGCs can thus potentially be a novel alternative to replace the damaged RGCs in glaucomatous retina.


Assuntos
Células-Tronco Germinativas Adultas/citologia , Terapia Baseada em Transplante de Células e Tecidos/métodos , Glaucoma/terapia , Células Ganglionares da Retina/transplante , Células-Tronco Germinativas Adultas/metabolismo , Animais , Biomarcadores/metabolismo , Diferenciação Celular , Modelos Animais de Doenças , Células-Tronco Embrionárias/citologia , Células-Tronco Embrionárias/metabolismo , Expressão Gênica , Genes Reporter , Glaucoma/induzido quimicamente , Glaucoma/genética , Glaucoma/patologia , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Injeções Intravítreas , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , N-Metilaspartato/administração & dosagem , Fator 3 de Transcrição de Octâmero/genética , Fator 3 de Transcrição de Octâmero/metabolismo , Cultura Primária de Células , Retina/efeitos dos fármacos , Retina/metabolismo , Retina/patologia , Células Ganglionares da Retina/citologia , Células Ganglionares da Retina/metabolismo , Testículo/citologia , Testículo/metabolismo , Fator de Transcrição Brn-3B/genética , Fator de Transcrição Brn-3B/metabolismo
12.
JAMA Ophthalmol ; 135(3): 189-195, 2017 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-28152147

RESUMO

IMPORTANCE: Measurement of the rates of retinal nerve fiber layer (RNFL) thinning has consisted primarily of the circumpapillary RNFL profile. This study reports the rates of RNFL thinning over the 6 × 6 mm2 RNFL thickness map and their application for indication of visual field (VF) worsening in patients with glaucoma. OBJECTIVE: To investigate the association between the rates of RNFL thinning and the risk of VF worsening in patients with glaucoma. DESIGN, SETTING, AND PARTICIPANTS: This prospective study included 117 eyes of 89 Chinese patients with primary open-angle glaucoma followed up at approximate 4-month intervals for 5 or more years between July 1, 2007, and October 30, 2015, with progressive RNFL thinning detected by optical coherence tomography trend-based progression analysis (TPA). The mean and the peak rates of RNFL thinning and the area of progressive RNFL thinning were measured by the rates of change of RNFL thickness map. Visual field worsening was determined by the Early Manifest Glaucoma Trial and pointwise linear regression criteria. MAIN OUTCOMES AND MEASURES: Hazard ratios (HRs) for indication of VF worsening determined by time-varying Weibull survival models. RESULTS: Of 89 patients (117 eyes) included in the study, 53 (59.6%) were men; mean (SD) age was 54.0 (13.8) years. At the time that progressive RNFL thinning was confirmed by TPA, the mean and the peak rates of RNFL thinning were 9.06 (8.05) µm/y and 4.52 (3.19) µm/y, respectively, and the area of progressive RNFL thinning was 1.54 (1.83) mm2. The inferotemporal meridians at 268° to 288° and the superotemporal meridians at 40° to 60° were the most frequent locations where progressive RNFL thinning was observed; 41.9% of the eyes had progressive RNFL thinning at these locations. After controlling for baseline covariates, the peak and the mean rates of RNFL thinning, but not the area of progressive RNFL thinning, were indicative of VF worsening. For each micrometer-per-year increase in the peak and the mean rates of RNFL thinning, the hazard ratios were 1.12 (95% CI, 1.04-1.19) for the peak rate and 1.39 (95% CI, 1.19-1.62) for the mean rate by the Early Manifest Glaucoma Trial criteria, and 1.07 (95% CI, 1.03-1.10) for the peak rate and 1.18 (95% CI, 1.09-1.28) for the mean rate by the pointwise linear regression criteria. CONCLUSIONS AND RELEVANCE: Topographic measurement of the rates of RNFL thinning by optical coherence tomography TPA is informative for risk assessment of VF loss in glaucoma. Although progressive RNFL thinning may not necessarily be associated with VF worsening, faster rates of RNFL thinning were associated with a higher risk of subsequent decline in VF.


Assuntos
Glaucoma de Ângulo Aberto/diagnóstico , Fibras Nervosas/patologia , Células Ganglionares da Retina/patologia , Tomografia de Coerência Óptica/métodos , Campos Visuais/fisiologia , Progressão da Doença , Feminino , Seguimentos , Glaucoma de Ângulo Aberto/complicações , Glaucoma de Ângulo Aberto/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Oligopeptídeos , Disco Óptico/patologia , Estudos Prospectivos , Escotoma/diagnóstico , Escotoma/etiologia , Escotoma/fisiopatologia , Fatores de Tempo
13.
Invest Ophthalmol Vis Sci ; 58(3): 1825-1833, 2017 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-28353690

RESUMO

Purpose: To investigate the impact of the rates of change of anterior lamina cribrosa surface depth (ALCSD) and optic nerve head surface depth (ONHSD) on visual field (VF) progression in glaucoma. Methods: One hundred forty-six eyes of 95 glaucoma patients had optical coherence tomography ONH imaging and VF testing at approximately 4-month intervals for greater than or equal to 5 years. Anterior lamina cribrosa surface depth and ONHSD were measured with reference to (1) Bruch's membrane opening (BMO), and (2) choroid-sclera interface (CSI). The rates of change of ALCSD and ONHSD of individual eyes were measured with linear regression analysis. The hazard ratios (HRs) of the rates of change of ALCSD/ONHSD for prediction of VF progression as per Early Manifest Glaucoma Trial criteria were determined by joint longitudinal and survival models. Results: Using the BMO reference, 23.3% and 28.1% of eyes showed a significant positive trend (posterior displacement), whereas 29.5% and 24.0% showed a significant negative trend (anterior displacement) of ALCSD and ONHSD, respectively. Using the CSI reference, the proportions with a significant negative trend decreased to 11.6% and 14.4%, respectively; and the proportions with a significant positive trend increased to 37.7% and 38.4%, respectively. The HRs of VF progression were 1.06 and 1.11 for each micrometer per year increase in the rates of change of ALCSDBMO and ONHSDBMO, respectively; and 1.07 and 1.09 for each micrometer per year increase in the rates of change of ALCSDCSI and ONHSDCSI, respectively. Conclusions: Identifying fast progressors of posterior ALCS/ONHS displacement is relevant to the management of glaucoma patients as they have a higher risk of VF progression.


Assuntos
Glaucoma/diagnóstico , Disco Óptico/patologia , Doenças do Nervo Óptico/diagnóstico , Tomografia de Coerência Óptica/métodos , Campos Visuais , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Progressão da Doença , Seguimentos , Glaucoma/complicações , Glaucoma/fisiopatologia , Humanos , Pressão Intraocular , Pessoa de Meia-Idade , Doenças do Nervo Óptico/etiologia , Doenças do Nervo Óptico/fisiopatologia , Estudos Prospectivos , Fatores de Tempo , Testes de Campo Visual , Adulto Jovem
15.
Mil Med ; 181(2): 136-42, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26837082

RESUMO

OBJECTIVE: Provider burnout can impact efficiency, empathy, and medical errors. Our study examines burnout in a military medical center during a period of war. METHODS: A survey including the Maslach Burnout Inventory (MBI), deployment history, and work variables was distributed to health care providers. MBI subscale means were calculated and associations between variables were analyzed. RESULTS: Approximately 60% of 523 respondents were active duty and 34% had deployed. MBI subscale means were 19.99 emotional exhaustion, 4.84 depersonalization, and 40.56 personal accomplishment. Frustration over administrative support was associated with high emotional exhaustion and depersonalization; frustration over life/work balance was associated with high emotional exhaustion. CONCLUSIONS: Levels of burnout in our sample were similar to civilian medical centers. Sources of frustration were related to administrative support and life/work balance. Deployment had no effect on burnout levels.


Assuntos
Esgotamento Profissional/epidemiologia , Pessoal de Saúde/psicologia , Guerra do Iraque 2003-2011 , Militares/psicologia , Estresse Psicológico , Adulto , Conflitos Armados/psicologia , Estudos Transversais , Feminino , Pessoal de Saúde/estatística & dados numéricos , Hospitais Militares , Humanos , Satisfação no Emprego , Masculino , Pessoa de Meia-Idade , Militares/estatística & dados numéricos , Inquéritos e Questionários , Estados Unidos/epidemiologia , Carga de Trabalho/psicologia , Carga de Trabalho/estatística & dados numéricos
16.
Invest Ophthalmol Vis Sci ; 53(11): 7194-200, 2012 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-22997288

RESUMO

PURPOSE: To investigate the association between the distribution profile of the retinal nerve fiber layer (RNFL) bundles and myopia and its impact on interpretation of the RNFL map imaged by a spectral-domain optical coherence tomography (SD-OCT). METHODS: the RNFL of 189 myopic eyes from 103 normal healthy myopic participants was imaged by an SD-OCT. The angle between the long axes of the superotemporal and inferotemporal RNFL bundles determined in the RNFL thickness map (the RNFL distribution angle) and the abnormal area in the RNFL thickness deviation map were measured. The associations between the RNFL distribution angle and the axial length/spherical error, and between the area of abnormal RNFL measurement and each of the following: axial length, spherical error, RNFL distribution angle, average RNFL thickness, optic disc area, and signal strength were analyzed with linear mixed models. RESULTS: The RNFL distribution angle decreased with the axial length (P < 0.011). In the univariate analysis, the area of abnormal RNFL measurement was positively associated with the axial length (P = 0.001); and negatively associated with the RNFL distribution angle (P < 0.001), average RNFL thickness (P < 0.001), optic disc area (P ≤ 0.001), and signal strength (P = 0.026). In the multivariate analysis, the area of abnormal RNFL measurement was negatively associated with the RNFL distribution angle independent of other covariates. CONCLUSIONS: The superotemporal and inferotemporal RNFL bundles converged temporally with increasing myopia, which was associated with an increase in area of abnormal RNFL measurement. The interpretation of the RNFL thickness map in myopic eyes requires careful consideration of the distribution pattern of the RNFL bundles.


Assuntos
Miopia/patologia , Disco Óptico/patologia , Células Ganglionares da Retina/patologia , Tomografia de Coerência Óptica/métodos , Adulto , Seguimentos , Humanos , Pessoa de Meia-Idade , Refração Ocular , Estudos Retrospectivos , Adulto Jovem
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