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Evidence for immediate hypersensitivity phenomena in experimental autoimmune uveoretinitis.

Evidence is presented for the involvement of immediate hypersensitivity phenomena in experimental autoimmune uveoretinitis, an ocular inflammatory disease induced in Lewis rats by injection of the purified S antigen from bovine retina. Several parameters at various dates after immunization have been studied. In vivo degranulation of choroidal mast cells, in vitro degranulation of peritoneal mast cells in the presence of S antigen and cutaneous anaphylaxis were observed as early as 6-8 days after immunization. Serum antibodies were detected by passive hemagglutination from day 7 on. These pheno…

Experimental macular edema after lens extraction.

Macular edema has been observed frequently in man after cataract extraction, but pathogenic mechanisms remain unclear. Seven eyes of four young adult rhesus monkeys underwent lens extraction. The retinas and maculae of these eyes were examined by ophthalmoscopy fundus photography, fluorescein angiography, light and electron microscopy, and the horseradish peroxidase tracer technique. In the macular region, the blood-retinal barrier at the retinal vasculature was disrupted in three of the seven eyes. All three eyes had had vitreous loss during lens extraction. Horseradish peroxidase was observe…

Experimental validation of the molecular mechanism of phlorizin in the treatment of diabetic retinopathy.

This study conducted an experiment to scrutinize the effect of phlorizin (Phl) on diabetic retinopathy (DR) and to delve into the related molecular mechanisms. Within this investigation, DR was induced in rats with diabetes mellitus (DM) by subjecting them to a regimen involving a high-fat and high-sugar diet, coupled with intraperitoneal administration of streptozotocin (STZ) at a dosage of 45 mg/kg. Retinal damage in DR rats was assessed by means of hematoxylin and eosin (HE) staining. The serum levels of inflammatory and angiogenic factors were also measured. Additionally, the levels of tig…

Intravitreal AAV2 gene delivery to feline retinal ganglion cells.

Effective strategies for the neuroprotection and preservation of retinal ganglion cells (RGCs) remain elusive in the management of glaucoma. A spontaneous genetic model of glaucoma has been identified in cats and extensively characterized as a viable translational model, with eye size and anatomy similar to humans. In this study we sought to establish initial proof of concept for gene delivery to feline RGCs via intravitreal injection of AAV2 in normal cats. Pre-retinal, posterior vitreal injection of AAV2/2-CMV-GFP, was performed overlying the area centralis in 5 adult cats. Immunosuppressive…

CCR7/p-ERK1/2/VEGF signaling promotes retinal neovascularization in a mouse model of oxygen-induced retinopathy.

AIM: To investigate the role of CCR7/p-ERK1/2/VEGF signaling in the mouse model of oxygen-induced retinopathy (OIR). METHODS: Neonatal C57B … of scramble or CCR7 siRNA plasmid on P12 before returning to normoxic conditions for 5d (P12-P17). Retina samples were collected from all mice on P17, stained with adenosine diphosphatase (ADPase), and retinal neovascularization (RNV) was assessed. Retinas were also stained with hematoxylin and eosin (H&E) for RNV quantitation. The distribution and expr …

Valproate promotes survival of retinal ganglion cells in a rat model of optic nerve crush.

Valproate (VPA) is an anticonvulsant and mood-stabilizing drug. It is a broad-spectrum histone deacetylase inhibitor with neuroprotective effects. We investigated whether VPA reduces retinal neuronal death induced by optic nerve crush (ONC). To evaluate further VPA-mediated neuroprotection on retinal ganglion cells (RGCs), another histone deacetylase (HDAC) inhibitor, sodium butyrate (SB) was compared with VPA. Adult male Wistar rats were subjected to ONC injury. VPA and SB were administered subcutaneously 1 day prior to ONC until sacrifice 14 days later. RGC density was counted using hematoxy…

Light-induced exacerbation of retinal degeneration in a rat model of Smith-Lemli-Opitz syndrome.

Potentiation of retinal degeneration by intense light exposure, and its amelioration by an antioxidant, were studied in a rat model of Smith-Lemli-Opitz syndrome (SLOS), in comparison with normal (control) Sprague-Dawley rats. The SLOS model is created by treating rats with AY9944, a selective inhibitor of cholesterol synthesis at the level of 3beta-hydroxysterol-Delta7-reductase. A subset of rats was treated with dimethylthiourea (DMTU), a synthetic antioxidant, 24 and 1 hr prior to light exposure. Half of the animals (+/-DMTU) were exposed to intense, constant, green light (24hr, 1700lx, 490…

Analysis of the Correlations between Relative Peripheral Refraction Errors and Myopia in Children and Adolescents.

INTRODUCTION: This study aimed to characterize relative peripheral refractive error (RPRE) using multispectral refraction topography (MRT) a … nt regions of children's eyes, summed to obtain its average value, and recorded separately based on retinal eccentricity and quadrants: 0°-53° retina (TRDV), eccentricity-specific defocus, and quadrant-based indices. Statistical analyses were performed using one-way analysis of variance (ANOVA) and multiple linear regression analysis. RESULTS: The TRDV …

Ultra-Widefield Optical Coherence Tomography Beyond the Ora Serrata in Retinopathy of Prematurity.

IMPORTANCE: Capturing high-quality images of the entire peripheral retina while minimizing the use of scleral depression could increase the quality of examinations for retinopathy of prematurity (ROP) while reducing neonatal stress. OBJECTIVE: To evaluate whether an investigational handheld ultra-widefield optical coherence tomography (UWF-OCT) device without scleral depression can be used to document high-quality images of the peripheral retina for use in ROP examinations. DESIGN, SETTING, AND PARTICIPANTS: This was a prospective, cross-sectional study in the neonatal intensive care unit at…

Interferons and Toxoplasma gondii shape PD-L1 regulation in retinal barrier cells: the critical role of proteases.

INTRODUCTION: The apicomplexan parasite Toxoplasma gondii establishes chronic infection in the central nervous system, including the retina, causing ocular toxoplasmosis (OT). This persistence relies on a fine balance between inflammatory and immunomodulatory mechanisms, especially in the immune-privileged ocular environment. We previously described the immunologic interactions between retinal cells, and particularly the roles of type I and III interferons. In this study, we investigated the regulatory dynamics of PD-L1, a central immunomodulatory receptor on immune cells. METHODS: We first i…

Thioredoxin-interacting protein (TXNIP) inhibition promotes retinal ganglion cell survival and facilitates M1-like microglial transformation via the PI3K/Akt pathway in glaucoma.

BACKGROUND: Glaucoma is a group of heterogeneous neurodegenerative diseases with abnormal energy metabolism and imbalanced neuroinflammation in the retina. Thioredoxin-interacting protein (TXNIP) is involved in glucose and lipid metabolism, and associated with oxidative stress and inflammation, however, not known whether to be involved in glaucoma neuropathy and its underlying mechanisms. METHODS: To establish the chronic ocular hypertension (COH) mice model. Western blot, RT-PCR, immunofluorescence and F-VEP were used to detect neuroinflammation level, glial activation and RGCs survival in r…

EyeArt artificial intelligence analysis of diabetic retinopathy in retinal screening events.

PURPOSE: Early detection and treatment of diabetic retinopathy (DR) are critical for decreasing the risk of vision loss and preventing blindness. Community vision screenings may play an important role, especially in communities at higher risk for diabetes. To address the need for increased DR detection and referrals, we evaluated the use of artificial intelligence (AI) for screening DR. METHODS: Patient images of 124 eyes were obtained using a 45° Canon Non-Mydriatic CR-2 Plus AF retinal camera in the Department of Endocrinology Clinic (Newark, NJ) and in a community screening event (Newark, …

Выявление маркеров оптической согласованности для многоразового диагностирования склероза и управления

Множественный склероз (MS) является распространенным неврологическим заболеванием, которое прямо или косвенно влияет на зрительный нерв в результате транссинаптического аксонаального дегенерации вдоль визуального пути. Новые офтальмологические инструменты, которые, возможно, являются наиболее важными в томографии оптической согласованности (OCT), могут сыграть важнейшую роль в пересмотре диагнозов MS и формировании их последующих протоколов, даже если в ней не участвует оптический нерв. МЕТОДЫ: Было проведено перспективное клиническое исследование. Всего, 158 Глаза пациентов, у которых ранее б

Совпадение в аннотации оригинала
BACKGROUND: Multiple sclerosis (MS) is a common neurological disease affecting the optic nerve, directly or indirectly, through transsynapti … ole analysis (PPA) and the optic nerve head radial circle protocol (ONH-RC)). RESULTS: The macular retinal thickness (the 4 × 4, respectively, 2 × 2 grid) and thickness of the peripapillary retinal nerve fiber layer (pRNFL) were investigated. Various layers of the retina were also compared. Our study observed significant pRNFL thinning in the RRMS eyes …

Central retinal artery occlusion without cherry-red spots.

BACKGROUND: Cherry-red spots are a very important sign for the clinical diagnosis of central retinal artery occlusion (CRAO). We retrospectively summarized the clinical manifestations of CRAO and analysed the causes and characteristics of CRAO without cherry-red spots. In this study, we explored a diagnostic method for CRAO without cherry red spots. METHODS: Seventy patients (70 eyes) with CRAO were examined retrospectively. Corrected distance visual acuity, fundus photos, FA and OCT images were collected at the first outpatient visit. The causes of CRAO without cherry-red spots were analysed…

Optimizing Retinal Thermofusion in Retinal Detachment Repair: Achieving Instant Adhesion without Air Tamponade.

PURPOSE: Rhegmatogenous retinal detachment repair by intraoperative sealing of the tear without a tamponade agent should enable faster restoration of vision and resumption of normal activities. It avoids the need for further surgery in the case of silicone oil endotamponade. This study evaluated the retinal thermofusion (RTF) retinopexy method of subretinal space dehydration before photocoagulation to create an instantaneous intraoperative retina reattachment in a preclinical model. DESIGN: Preclinical study. PARTICIPANTS: Twenty Dutch Belt, pigmented rabbits that underwent RTF repair after …

Intravitreal methotrexate infusion for prophylaxis of proliferative vitreoretinopathy after pars plana vitrectomy for rhegmatogenous retinal detachment.

BACKGROUND: Proliferative vitreoretinopathy (PVR) is the leading cause of recurrent retinal detachment after surgical repair of rhegmatogenous retinal detachment (RRD). Our study aimed to assess the efficacy and safety of intravitreal methotrexate infusion (IMI) for the prevention of PVR after pars plana vitrectomy (PPV) in eyes with RRD. METHODS: This prospective comparative interventional study was conducted from September 2020 to November 2021 at Ain Shams University Hospitals, Egypt. We recruited a consecutive, non-randomized sample of 47 eyes of 47 patients with RRD undergoing PPV. Parti…

The cytokine IL-27 reduces inflammation and protects photoreceptors in a mouse model of retinal degeneration.

BACKGROUND: Retinal degenerative diseases are a group of conditions characterized by photoreceptor death and vision loss. Excessive inflammation and microglial activation contribute to the pathology of retinal degenerations and a major focus in the field is identifying more effective anti-inflammatory therapeutic strategies that promote photoreceptor survival. A major challenge to developing anti-inflammatory treatments is to selectively suppress detrimental inflammation while maintaining beneficial inflammatory responses. We recently demonstrated that endogenous levels of the IL-27 cytokine w…

Changes in macrophage-like cells characterized by en face optical coherence tomography after retinal stroke.

PURPOSE: The retina could serve as a window of neuroinflammation, but the in vivo changes in macrophage-like cell (MLC), such as microglia, in acute ischemic retinal stroke remain unclear. Thus, the current study aimed to investigate the in vivo changes in MLC characterized by en face optical coherence tomography (OCT) after acute ischemic retinal stroke. METHODS: Twenty patients with unilateral acute nonarteritic reperfused central retinal artery occlusion (CRAO) were participated in this study, and their contralateral eyes served as control group. A 3 μm en face OCT slab on the inner limiti…

In vivo Retinal Fluorescence Imaging With Curcumin in an Alzheimer Mouse Model.

Alzheimer's disease (AD) is characterized by amyloid beta (Aβ) plaques in the brain detectable by highly invasive in vivo brain imaging or in post-mortem tissues. A non-invasive and inexpensive screening method is needed for early diagnosis of asymptomatic AD patients. The shared developmental origin and similarities with the brain make the retina a suitable surrogate tissue to assess Aβ load in AD. Using curcumin, a FluoroProbe that binds to Aβ, we labeled and measured the retinal fluorescence in vivo and compared with the immunohistochemical measurements of the brain and retinal Aβ load in t…

Treatment outcomes of zone 1 retinopathy of prematurity: A study from a tertiary eye care center in South India.

PURPOSE: The main purpose is to study the treatment outcomes of zone 1 retinopathy of prematurity (ROP). MATERIALS AND METHODS: A retrospective analysis was done of infants diagnosed with zone 1 ROP with any stage with or without plus disease who were treated with either laser photocoagulation and/or intravitreal injection of antivascular endothelial growth factor (anti-VEGF) agents and/or underwent surgery according to their stage at presentation. The retinal outcome at the final visit was analyzed. A favorable outcome was characterized by an attached retina at the posterior pole with regres…