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1.
Retin Cases Brief Rep ; 16(4): 457-460, 2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32502130

RESUMO

PURPOSE: To present two patients with treatment-naïve posterior segment uveitis with Vogt-Koyanagi-Harada-like features associated with tattoo-related inflammatory skin changes. METHODS: Retrospective report of two cases. RESULTS: Using clinical history and multimodal imaging, a diagnosis of posterior segment uveitis with Vogt-Koyanagi-Harada-like features was made in association with tattoo skin changes in both patients. CONCLUSION: Physicians should be aware that tattoo-associated posterior segment uveitis with Vogt-Koyanagi-Harada-like features can occur.


Assuntos
Tatuagem , Uveíte Posterior , Uveíte , Síndrome Uveomeningoencefálica , Humanos , Estudos Retrospectivos , Tatuagem/efeitos adversos , Síndrome Uveomeningoencefálica/complicações , Síndrome Uveomeningoencefálica/diagnóstico
2.
Clin Exp Ophthalmol ; 49(9): 1048-1059, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34549489

RESUMO

BACKGROUND: Treatment options for severe ocular von Hippel-Lindau (VHL) disease are limited. This trial evaluated preliminary safety and potential efficacy of combination intravitreous injection with ranibizumab, a vascular endothelial growth factor (VEGF) inhibitor, and E10030, a PDGF inhibitor, for eyes with VHL disease-associated retinal hemangioblastoma (RH) not amenable or responsive to thermal laser photocoagulation. METHODS: This was a prospective, single-arm, open-label phase 1/2 study, comprised of three adults with VHL-associated RH and vision loss. Intravitreous injections of ranibizumab (0.5 mg) and E10030 (1.5 mg) were given unilaterally every 4 weeks in the study eye through 16 weeks, then every 8 weeks through 48 weeks. Supplementary standard care therapies were allowed without restriction after 40 weeks. The primary outcome was the ocular and systemic adverse effect profile at 52 weeks. Secondary outcomes included changes in best-corrected visual acuity (BCVA), RH size, exudation, epiretinal proliferation and retinal traction, and need for ablative treatment of RH or ocular surgery at week 52. RESULTS: Three participants each received nine injections prior to week 52 and were followed for 104 weeks. One participant manifested mild episodic ocular hypertension in the study eye. Change in BCVA in the study eye at week 52 for the three participants was -5, -12 and +2 letters. No reduction in RH size was measured at 52 weeks. Variable mild improvements in exudation in two participants at week 16 were not sustained through week 52. CONCLUSIONS: Combination intravitreous injection with ranibizumab and E10030 demonstrated a reasonable preliminary safety profile, but limited treatment effect.


Assuntos
Aptâmeros de Nucleotídeos , Doença de von Hippel-Lindau , Adulto , Inibidores da Angiogênese/uso terapêutico , Aptâmeros de Nucleotídeos/uso terapêutico , Humanos , Injeções Intravítreas , Estudos Prospectivos , Ranibizumab/uso terapêutico , Fator A de Crescimento do Endotélio Vascular , Acuidade Visual , Doença de von Hippel-Lindau/tratamento farmacológico
4.
Ophthalmol Retina ; 5(2): 108-117, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33075546

RESUMO

PURPOSE: To examine whether the rate of geographic atrophy (GA) enlargement is influenced by subsequent exudative neovascular age-related macular degeneration (nAMD) and hence, to explore indirectly whether nonexudative nAMD may slow GA enlargement. DESIGN: Post hoc analysis of a controlled clinical trial cohort. PARTICIPANTS: Age-Related Eye Disease Study 2 participants 50 to 85 years of age. METHODS: Baseline and annual stereoscopic color fundus photographs were evaluated for (1) GA presence and area and (2) exudative nAMD presence. Two cohorts were constructed: eyes with GA at study baseline (prevalent cohort) and eyes in which GA developed during follow-up (incident cohort). Mixed-model regression of the square root of GA area was performed according to the presence or absence of subsequent exudative nAMD. MAIN OUTCOME MEASURES: Change over time in square root of GA area. RESULTS: Of the 757 eyes in the incident GA cohort, over a mean follow-up of 2.3 years (standard deviation [SD], 1.2 years), 73 eyes (9.6%) demonstrated subsequent exudative nAMD. Geographic atrophy enlargement in these eyes was significantly slower (0.20 mm/year; 95% confidence interval [CI], 0.12-0.28 mm/year) compared with the other 684 eyes in which subsequent exudative nAMD did not develop (0.29 mm/year; 95% CI, 0.27-0.30 mm/year; P = 0.037). Of the 456 eyes in the prevalent GA cohort, over a mean follow-up of 4.1 years (SD, 1.4 years), 63 eyes (13.8%) demonstrated subsequent exudative nAMD. Geographic atrophy enlargement in these eyes was similar (0.31 mm/year; 95% CI, 0.24-0.37 mm/year) compared with the other 393 eyes in which subsequent exudative nAMD did not develop (0.28 mm/year; 95% CI, 0.26-0.29 mm/year; P = 0.37). CONCLUSIONS: In eyes with recent GA, GA enlargement before the development of exudative nAMD seems slowed. This association was not observed in eyes with more long-standing GA, which have larger lesion sizes. Hence, perilesional nonexudative choroidal neovascular tissue (presumably present before the development of clinically apparent exudation) may slow enlargement of smaller GA lesions through improved perfusion. This hypothesis warrants further evaluation in prospective studies.


Assuntos
Ácidos Docosa-Hexaenoicos/farmacologia , Ácido Eicosapentaenoico/farmacologia , Atrofia Geográfica/complicações , Luteína/farmacologia , Macula Lutea/patologia , Degeneração Macular Exsudativa/diagnóstico , Zeaxantinas/farmacologia , Idoso , Idoso de 80 Anos ou mais , Diagnóstico por Imagem/métodos , Progressão da Doença , Quimioterapia Combinada , Feminino , Seguimentos , Atrofia Geográfica/diagnóstico , Atrofia Geográfica/tratamento farmacológico , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Resultado do Tratamento , Degeneração Macular Exsudativa/etiologia , Degeneração Macular Exsudativa/prevenção & controle
5.
Am J Ophthalmol Case Rep ; 20: 100866, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32875152

RESUMO

PURPOSE: To describe multimodal imaging findings with focus on retinal and choroidal vascular features in acute macular neuroretinopathy (AMN). OBSERVATIONS: Three eyes from 3 patients (1 man, 2 women) with average age of 31 were included in this retrospective case series at a single institution. Each case showed petaloid hyporeflective areas on infrared images (IR) with variable levels of outer retinal defects on spectral domain optical coherence tomography (OCT). En face OCT angiography (OCT-A) images showed quantifiable reduction in vessel density at levels of the deep capillary plexus (DCP) and choriocapillaris (CC) layers. In 2 of the cases with near-infrared autofluorescence imaging (NIRAF), there were subtle areas of hypoautofluorescence corresponding in location to the lesions seen on IR. In one case, fluorescein angiography (FA) showed a small area of retinal vascular leakage in the area of the IR lesion, and in other 2 cases, there were paracentral areas of hypofluorescence in the area of the IR lesions. En face structural OCT image at the retinal pigment epithelium (RPE) level in each case showed no evidence of projection artifact from the retina. CONCLUSIONS AND IMPORTANCE: The pathogenesis of AMN is suspected to involve a vasogenic insult. However, the precise localization of the vascular insult has been controversial and unclear. Our findings demonstrate that concurrent vascular flow defects in both DCP and CC could be possible in AMN and suggest that an inflammatory and vascular etiology in concert could underlie the pathogenesis of AMN.

6.
Ophthalmology ; 127(12): 1674-1687, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32447042

RESUMO

PURPOSE: To develop deep learning models for detecting reticular pseudodrusen (RPD) using fundus autofluorescence (FAF) images or, alternatively, color fundus photographs (CFP) in the context of age-related macular degeneration (AMD). DESIGN: Application of deep learning models to the Age-Related Eye Disease Study 2 (AREDS2) dataset. PARTICIPANTS: FAF and CFP images (n = 11 535) from 2450 AREDS2 participants. Gold standard labels from reading center grading of the FAF images were transferred to the corresponding CFP images. METHODS: A deep learning model was trained to detect RPD in eyes with intermediate to late AMD using FAF images (FAF model). Using label transfer from FAF to CFP images, a deep learning model was trained to detect RPD from CFP (CFP model). Performance was compared with 4 ophthalmologists using a random subset from the full test set. MAIN OUTCOME MEASURES: Area under the receiver operating characteristic curve (AUC), κ value, accuracy, and F1 score. RESULTS: The FAF model had an AUC of 0.939 (95% confidence interval [CI], 0.927-0.950), a κ value of 0.718 (95% CI, 0.685-0.751), and accuracy of 0.899 (95% CI, 0.887-0.911). The CFP model showed equivalent values of 0.832 (95% CI, 0.812-0.851), 0.470 (95% CI, 0.426-0.511), and 0.809 (95% CI, 0.793-0.825), respectively. The FAF model demonstrated superior performance to 4 ophthalmologists, showing a higher κ value of 0.789 (95% CI, 0.675-0.875) versus a range of 0.367 to 0.756 and higher accuracy of 0.937 (95% CI, 0.907-0.963) versus a range of 0.696 to 0.933. The CFP model demonstrated substantially superior performance to 4 ophthalmologists, showing a higher κ value of 0.471 (95% CI, 0.330-0.606) versus a range of 0.105 to 0.180 and higher accuracy of 0.844 (95% CI, 0.798-0.886) versus a range of 0.717 to 0.814. CONCLUSIONS: Deep learning-enabled automated detection of RPD presence from FAF images achieved a high level of accuracy, equal or superior to that of ophthalmologists. Automated RPD detection using CFP achieved a lower accuracy that still surpassed that of ophthalmologists. Deep learning models can assist, and even augment, the detection of this clinically important AMD-associated lesion.


Assuntos
Aprendizado Profundo , Angiofluoresceinografia , Imagem Óptica , Drusas Retinianas/diagnóstico por imagem , Idoso , Idoso de 80 Anos ou mais , Área Sob a Curva , Conjuntos de Dados como Assunto , Feminino , Humanos , Degeneração Macular , Masculino , Pessoa de Meia-Idade , Oftalmologistas , Curva ROC , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
7.
Am J Ophthalmol Case Rep ; 18: 100664, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32211564

RESUMO

PURPOSE: To report the clinical course of two cases with Purtscher-like retinopathy (PLR), associated with peritoneal dialysis (PD), demonstrating disease recurrence and progression to neovascularization and vitreous hemorrhage. OBSERVATIONS: Case 1 (45-year old woman) experienced acute bilateral vision loss. Medical history included hypertension, end-stage renal failure (ESRF), PD, and obstructive sleep apnea. Visual acuity (VA) was 20/100 OD, 20/80 OS. Fundus findings were pathognomonic for PLR and included white streaks within arterioles. Nine months later, repeat imaging demonstrated disease recurrence and progression, including increased ischemia and new retinal neovascularization. The patient was managed with pan-retinal photocoagulation, sleep apnea treatment, and oral corticosteroids. Four months later, VA remained stable without additional progression.Case 2 (74-year old woman) experienced acute bilateral vision loss. Medical history included hypertension, ESRF, and PD, complicated by peritonitis. VA was 20/25 OD, 20/32 OS. Fundus findings were pathognomonic for PLR and included white streaks within arterioles. Three months later, further acute vision loss occurred, coinciding with recurrent peritonitis. Repeat imaging revealed disease recurrence and progression, including severely increased retinal ischemia. The PD catether was removed and the patient converted to hemodialysis. Bilateral vitreous hemorrhage later complicated the course. CONCLUSIONS AND IMPORTANCE: PLR can occur in association with PD, particularly in acute peritonitis. Contrary to classical descriptions, PLR may take a chronic and progressive course, with increasing ischemia and progression to neovascularization or vitreous hemorrhage. Increased surveillance for complications is recommended and treatment of neovascularization may be required.

9.
J Med Case Rep ; 12(1): 349, 2018 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-30442199

RESUMO

BACKGROUND: Ibrutinib is a tyrosine kinase inhibitor commonly used in patients with chronic lymphocytic leukemia. Based on the published literature, it has a very sound ophthalmologic safety profile. In the following, we describe a case of anterior chamber fibrinoid syndrome in a patient on ibrutinib for B-cell chronic lymphocytic leukemia after uncomplicated cataract extraction. CASE PRESENTATION: A 75-year-old white man with B-cell chronic lymphocytic leukemia on ibrutinib therapy and without significant past ocular history presented 1 day after uncomplicated phacoemulsification with in-the-bag intraocular lens implantation with multiple, discrete, pigmented cords in the anterior chamber. His vision was 20/100 and intraocular pressure was 43 mmHg. There was no hypopyon, hyphema, or cellular reaction. The dilated fundus examination was unremarkable. He was diagnosed as having fibrinoid syndrome and started on topical prednisolone, brimonidine, timolol-dorzolamide, and orally administered acetazolamide. Within 2 weeks, the fibrin cords disappeared completely, vision improved to 20/30, and the intraocular pressure normalized off all medications. CONCLUSIONS: The precise etiology of fibrinoid syndrome remains unclear. This is the first case of fibrinoid syndrome in a patient on ibrutinib, which is known to cross the blood-brain barrier and induce intraocular changes. It is important to differentiate this syndrome from toxic anterior segment syndrome and endophthalmitis, and to initiate appropriate treatment. The fibrin bands tend to be exquisitely sensitive to topical steroids and to resolve within a few weeks without sequelae.


Assuntos
Câmara Anterior/patologia , Anti-Hipertensivos/administração & dosagem , Antineoplásicos/efeitos adversos , Extração de Catarata/efeitos adversos , Pressão Intraocular/efeitos dos fármacos , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Pirazóis/efeitos adversos , Pirimidinas/efeitos adversos , Adenina/análogos & derivados , Administração Tópica , Idoso , Câmara Anterior/fisiopatologia , Antineoplásicos/administração & dosagem , Tartarato de Brimonidina/administração & dosagem , Humanos , Masculino , Facoemulsificação , Piperidinas , Prednisolona/administração & dosagem , Pirazóis/administração & dosagem , Pirimidinas/administração & dosagem , Sulfonamidas/administração & dosagem , Síndrome , Tiofenos/administração & dosagem , Timolol/administração & dosagem , Resultado do Tratamento , Acuidade Visual
12.
Ophthalmology ; 122(5): 1008-15, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25687024

RESUMO

PURPOSE: To determine the relative effectiveness, major complications, and refractive errors associated with intravitreal bevacizumab (IVB) versus panretinal photocoagulation (PRP) to treat type 1 retinopathy of prematurity (ROP). DESIGN: Retrospective case series. PARTICIPANTS: Consecutive infants with type 1 ROP who received either IVB or PRP and had at least 6 months of follow-up. METHODS: The data from infants treated with either IVB or PRP for type 1 ROP between 2008 and 2012 were recorded from 2 medical centers in Atlanta, Georgia. MAIN OUTCOME MEASURES: Recurrence rate, complication rate, and refractive error. RESULTS: A total of 54 eyes (28 patients) with type 1 ROP were evaluated: 22 eyes (11 patients) received IVB, and 32 eyes (17 patients) received PRP. Among the 22 eyes treated with IVB, 16 eyes had zone I ROP and 6 eyes had posterior zone II ROP. The number of zone I and II ROP eyes treated with PRP were 5 and 27, respectively. Mean gestational age, birth weight, postmenstrual age at initial treatment, and follow-up period for the infants receiving IVB were 24.2 weeks, 668.1 g, 35.1 weeks, and 21.7 weeks, respectively, and for the infants receiving PRP, these were 24.8 weeks, 701.4 g, 36.1 weeks, and 34.5 weeks, respectively. Retinopathy of prematurity recurred in 3 (14%) of 22 IVB-treated eyes and in 1 (3%) of 32 PRP-treated eyes. Neither retinal detachment nor macular ectopia developed in any of the IVB-treated eyes. In PRP-treated eyes, retinal detachment developed in only 1 eye and macular ectopia developed in 5 eyes. Mean spherical equivalent and postgestational age at the last refraction for IVB-treated eyes were -2.4 diopters (D) and 22.4 months, respectively, and for PRP-treated eyes, these were -5.3 D and 37.1 months, respectively. Mean spherical equivalent for zone I ROP eyes treated with IVB and PRP were -3.7 D and -10.1 D, respectively, and for zone II ROP eyes, these were 0.6 D and -4.7 D, respectively. CONCLUSIONS: Both IVB and PRP are effective treatment options for type 1 ROP with low complication rates. IVB was associated with less myopia than PRP, although longer follow-up was available for PRP.


Assuntos
Inibidores da Angiogênese/uso terapêutico , Anticorpos Monoclonais Humanizados/uso terapêutico , Fotocoagulação a Laser , Retinopatia da Prematuridade/terapia , Bevacizumab , Peso ao Nascer , Feminino , Seguimentos , Idade Gestacional , Humanos , Recém-Nascido , Complicações Intraoperatórias , Injeções Intravítreas , Masculino , Complicações Pós-Operatórias , Erros de Refração/fisiopatologia , Retinopatia da Prematuridade/tratamento farmacológico , Retinopatia da Prematuridade/cirurgia , Estudos Retrospectivos , Resultado do Tratamento , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores
13.
PLoS One ; 9(2): e88217, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24558381

RESUMO

The purpose of this study was to expand our knowledge of small RNAs, which are known to function within protein complexes to modulate the transcriptional output of the cell. Here we describe two previously unrecognized, small RNAs, termed pY RNA1-s1 and pY RNA1-s2 (processed Y RNA1-stem -1 and -2), thereby expanding the list of known small RNAs. pY RNA1-s1 and pY RNA1-s2 were discovered by RNA sequencing and found to be 20-fold more abundant in the retina than in 14 other rat tissues. Retinal expression of pY RNAs is highly conserved, including expression in the human retina, and occurs in all retinal cell layers. Mass spectrometric analysis of pY RNA1-S2 binding proteins in retina indicates that pY RNA1-s2 selectively binds the nuclear matrix protein Matrin 3 (Matr3) and to a lesser degree to hnrpul1 (heterogeneous nuclear ribonucleoprotein U-like protein). In contrast, pY RNA1-s1 does not bind these proteins. Accordingly, the molecular mechanism of action of pY RNA1-s2 is likely be through an action involving Matr3; this 95 kDa protein has two RNA recognition motifs (RRMs) and is implicated in transcription and RNA-editing. The high affinity binding of pY RNA1-s2 to Matr3 is strongly dependent on the sequence of the RNA and both RRMs of Matr3. Related studies also indicate that elements outside of the RRM region contribute to binding specificity and that phosphorylation enhances pY RNA-s2/Matr3 binding. These observations are of significance because they reveal that a previously unrecognized small RNA, pY RNA1-s2, binds selectively to Matr3. Hypothetically, pY RNA1-S2 might act to modulate cellular function through this molecular mechanism. The retinal enrichment of pY RNA1-s2 provides reason to suspect that the pY RNA1-s2/Matr3 interaction could play a role in vision.


Assuntos
Proteínas Associadas à Matriz Nuclear/genética , Proteínas Associadas à Matriz Nuclear/metabolismo , Proteínas Nucleares/metabolismo , Pequeno RNA não Traduzido/metabolismo , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Retina/metabolismo , Adulto , Motivos de Aminoácidos , Animais , Sequência de Bases , Bovinos , Galinhas , Feminino , Ribonucleoproteínas Nucleares Heterogêneas/metabolismo , Humanos , Macaca mulatta , Masculino , Espectrometria de Massas , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade , Dados de Sequência Molecular , Conformação de Ácido Nucleico , Fosforilação , Glândula Pineal/metabolismo , Ligação Proteica , Estrutura Terciária de Proteína , Interferência de RNA , Ratos Sprague-Dawley , Ovinos , Distribuição Tecidual
14.
Diabetes Res Clin Pract ; 104(2): 206-13, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24507869

RESUMO

AIM: To investigate diabetes prevalence in rural areas globally and how it has changed over time in high-income countries (HIC) and low-middle income countries (LMIC). METHODS: We systematically searched four electronic databases (MEDLINE, EMBASE, Cochrane Library, and CINAHL) for studies reporting rural prevalence of diabetes between January 1990 and January 2012. We used random effect meta-analysis to estimate pooled prevalence and metaregression to identify factors that may be associated with our estimates. FINDINGS: We included 109 population-based surveys involving 1,100,746 individuals. Pooled global rural prevalence of diabetes was 6.8% (95% confidence intervals: 6.1-7.6) with no gender difference. Considering five-year increments between 1985 and 2011, when studies were conducted, global rural prevalence was 5.7% (3.5-7.9) during 1985-1989 and 8.7% (6.8-10.7) during 2005-2011. In LMICs, rural diabetes prevalence was 1.8% (1.0-2.6) during 1985-1989 and 7.5% (5.6-9.5) during 2005-2011. In HICs, rural diabetes prevalence was 8.2% (6.0-10.4) during 1985-1989 and 14.3% (8.7-20) in the most recent period. CONCLUSION: Diabetes prevalence has increased in all rural areas globally but relative growth was faster in LMIC than HIC rural areas. These data suggest a need to expand diabetes surveillance to rural areas using standardized measures, as well as the need to devise and deploy appropriate prevention and control interventions.


Assuntos
Países em Desenvolvimento , Diabetes Mellitus/epidemiologia , Previsões , População Rural , Humanos , Pobreza , Prevalência
15.
Ocul Oncol Pathol ; 1(1): 34-8, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27175360

RESUMO

BACKGROUND/AIMS: To report a case of subretinal bone formation after the treatment with denosumab for a giant cell tumor of the sphenoid, which had recurred after surgical resection. METHODS: The clinical history and fundus findings including imaging, histologic and immunohistochemical features of the primary tumor and subretinal lesion were reviewed. RESULTS: A 14-year-old boy was evaluated for a suprasellar mass. Resection of the lesion showed giant cell tumor of bone (GCT). An MRI study at the 1-month follow-up appointment showed tumor progression, and denosumab was initiated. Two months after the initial presentation, the patient developed a worsening scotoma of the right eye. Dilated fundus examination showed a yellow-tan-colored subretinal mass temporal to the fovea. The subretinal lesion was removed and showed lamellar bone with associated fibrocellular tissue. CONCLUSION: Denosumab therapy for GCT of the sphenoid may be associated with subretinal bone formation.

16.
J Neurosci ; 33(38): 14989-97, 2013 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-24048828

RESUMO

Spatial variation in light intensity, called spatial contrast, comprises much of the visual information perceived by mammals, and the relative ability to detect contrast is referred to as contrast sensitivity (Purves et al., 2012). Recently, retinal dopamine D4 receptors (D4Rs) have been implicated in modulating contrast sensitivity (Jackson et al., 2012); however, the cellular and molecular mechanisms have not been elucidated. Our study demonstrates a circadian rhythm of contrast sensitivity that peaks during the daytime, and that its regulation involves interactions of D4Rs, the clock gene Npas2, and the clock-controlled gene adenylyl cyclase 1 (Adcy1) in a subset of retinal ganglion cells (RGCs). Targeted disruption of the gene encoding D4Rs reduces the amplitude of the contrast sensitivity rhythm by reducing daytime sensitivity and abolishes the rhythmic expression of Npas2 and Adcy1 mRNA in the ganglion cell layer (GCL) of the retina. Npas2(-/-) and Adcy1(-/-) mice show strikingly similar reductions in the contrast sensitivity rhythm to that in mice lacking D4Rs. Moreover, Adcy1 transcript rhythms were abolished in the GCL of Npas2(-/-) mice. Luciferase reporter assays demonstrated that the Adcy1 promoter is selectively activated by neuronal PAS-domain protein 2 (NPAS2)/BMAL1. Our results indicate that the contrast sensitivity rhythm is modulated by D4Rs via a signaling pathway that involves NPAS2-mediated circadian regulation of Adcy1. Hence, we have identified a circadian clock mechanism in a subset of RGCs that modulates an important aspect of retinal physiology and visual processing.


Assuntos
Ritmo Circadiano/fisiologia , Sensibilidades de Contraste/fisiologia , Dopamina/metabolismo , Células Ganglionares da Retina/metabolismo , Transdução de Sinais/fisiologia , Fatores de Transcrição ARNTL/metabolismo , Adenilil Ciclases/deficiência , Adenilil Ciclases/genética , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Linhagem Celular Transformada , Ritmo Circadiano/genética , Sensibilidades de Contraste/genética , Regulação da Expressão Gênica/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Mutação/genética , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Estimulação Luminosa , Receptores de Dopamina D4/genética , Receptores de Dopamina D4/metabolismo , Retina , Transfecção , Acuidade Visual , Vias Visuais/fisiologia , beta-Galactosidase/genética , beta-Galactosidase/metabolismo
17.
Mol Vis ; 19: 1122-4, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23734080

RESUMO

PURPOSE: Mice are commonly used in biomedical research, and euthanasia is an important part of mouse husbandry. Approved, humane methods of euthanasia are designed to minimize the potential for pain or discomfort, but may also influence the measurement of experimental variables. METHODS: We compared the effects of two approved methods of mouse euthanasia on the levels of retinal dopamine. We examined the level of retinal dopamine, a commonly studied neuromodulator, following euthanasia by carbon dioxide (CO2)-induced asphyxiation or by cervical dislocation. RESULTS: We found that the level of retinal dopamine in mice euthanized through CO2 overdose substantially differed from that in mice euthanized through cervical dislocation. CONCLUSIONS: The use of CO2 as a method of euthanasia could result in an experimental artifact that could compromise results when studying labile biologic processes.


Assuntos
Dopamina/metabolismo , Eutanásia Animal/métodos , Retina/metabolismo , Ácido 3,4-Di-Hidroxifenilacético/metabolismo , Animais , Masculino , Camundongos
18.
Exp Eye Res ; 103: 82-9, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22960156

RESUMO

In the vertebrate retina, melatonin is synthesized by the photoreceptors with high levels of melatonin at night and lower levels during the day. Melatonin exerts its influence by interacting with a family of G-protein-coupled receptors that are negatively coupled with adenylyl cyclase. Melatonin receptors belonging to the subtypes MT(1) and MT(2) have been identified in the mammalian retina. MT(1) and MT(2) receptors are found in all layers of the neural retina and in the retinal pigmented epithelium. Melatonin in the eye is believed to be involved in the modulation of many important retinal functions; it can modulate the electroretinogram (ERG), and administration of exogenous melatonin increases light-induced photoreceptor degeneration. Melatonin may also have protective effects on retinal pigment epithelial cells, photoreceptors and ganglion cells. A series of studies have implicated melatonin in the pathogenesis of age-related macular degeneration, and melatonin administration may represent a useful approach to prevent and treat glaucoma. Melatonin is used by millions of people around the world to retard aging, improve sleep performance, mitigate jet lag symptoms, and treat depression. Administration of exogenous melatonin at night may also be beneficial for ocular health, but additional investigation is needed to establish its potential.


Assuntos
Melatonina/fisiologia , Retina/fisiologia , Retina/fisiopatologia , Ritmo Circadiano/fisiologia , Humanos , Receptores de Melatonina/metabolismo , Degeneração Retiniana/fisiopatologia
20.
Diabetes Res Clin Pract ; 96(3): 271-85, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22261096

RESUMO

AIMS: To verify the assertions that diabetes pandemic may be spreading across rural parts of low- and middle-income countries (LMICs), we performed a systematic review of published studies reporting diabetes prevalence in rural parts of LMICs. METHODS: Electronic databases (EMBASE and MEDLINE) were searched for papers published from 1990 to 2011. Two independent reviewers screened the articles using structured criteria for inclusion and performed full-text reviews. Pooled prevalence of diabetes was estimated using meta-analysis. Potential factors influencing the estimates were identified by meta-regression and used for sensitivity analyses. RESULTS: Rural prevalence of diabetes of LMICs was 5.6% (95% CI=4.6-6.6), and similar between men and women. This estimate remained robust in separate sensitivity analyses accounting for study quality, level of heterogeneity, age, and sex. In a multivariate meta-regression analysis, pooled prevalence varied by study year and region. Diabetes prevalence increased over time, from 1.8% (1.0-2.6) in 1985-1989, 5.0% (3.8-6.3) in 1990-1994, 5.2% (4.1-6.2) in 1995-1999, 6.4% (5.1-7.7) in 2000-2004, and to 8.6% (6.4-10.7) for 2005-2010 (p=0.001 for secular trend). CONCLUSIONS: Prevalence of diabetes in rural parts of LMICs has risen dramatically. As 55% of LMIC populations live in rural areas, this trend has enormous implications for the global burden of diabetes.


Assuntos
Países em Desenvolvimento/estatística & dados numéricos , Diabetes Mellitus/epidemiologia , População Rural/estatística & dados numéricos , Adulto , Distribuição por Idade , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Prevalência , Medição de Risco , Distribuição por Sexo , Fatores Socioeconômicos
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