Correlation between different retinal layers with visual acuity in diabetic retinopathy patients with clinically significant macular edema

Purpose: To study the corelation between outer retinal layer thickness (ORL), outer photoreceptor segment thickness (PROS), and central macular thickness (CMT) with best?corrected visual acuity (BCVA) in patients having clinically significant macular edema (CSME) and compare these parameters with normal patients. Methods: This was a prospective, nonrandomized, observational, comparative study done during the period of January to May 2019. The study included 60 eyes of 36 patients. The patient population was segregated into two Groups: Group ? (30 normal eyes of 15 normal patients) and Group ?? (30 eyes of 21 diabetic patients) with CSME. The comparison between ORL, PROS, and CMT was made between both the groups, and the correlation between ORL thickness, PROS thickness, and CMT with BCVA in Group ?? was studied. Results: The mean age in Group I was 52.6+10.66 years, and 53.42+8.15 years in Group II. The male/ female ratio was 1.1:1 in Group I and 4:3 in Group II. The mean CMT was greater in Group ?? (330.13 ± 37.01) than in Group ? (222.20 ± 12.30). The mean ORL thickness was greater in Group ? (97.73 ± 6.92) than in Group ?? (80.63 ± 9.03). The PROS thickness was statistically significant in Group ? (35.05 ± 3.4) than in Group ?? (28.57 ± 3.53). There was a strong correlation between BCVA and ORL thickness (r = ?0.580, P < 0.001) and more strong correlation between BCVA and PROS thickness in Group ?? (r = ?0.611, P < 0.000). There was a moderate correlation between BCVA and CMT (r = 0.410, P < 0.025), and all results were statistically significant. Conclusion: Both ORL and PROS thickness were greater in healthy normal eyes than in eyes with CSME. BCVA was strongly correlated with PROS and ORL thickness and moderately associated with CMT.

Desprendimiento de la capa bacilar de la retina asociado a enfermedad inflamatoria ocular

El desprendimiento de la capa bacilar de la retina es la separación de los segmentos internos de los fotorreceptores del resto de la retina neurosensorial, o separación entre la zona miode y elipsoide de la retina, que en un hallazgo reciente se puede identificar mediante la tomografía de coherencia óptica de dominio espectral. El objetivo es actualizar los conocimientos sobre el desprendimiento de la capa bacilar de la retina y el uso de la tomografía de coherencia óptica de dominio espectral en las enfermedades oculares que están asociadas con este signo. Se consultaron las fuentes bibliográficas como Google académico, SciELO LAC, Medline y MEDICARIBE. Se limitaron los resultados al idioma español e inglés y a los últimos cinco años. Se recuperaron 54 documentos, de ellos 18 resultaron relevantes a esta investigación. Los autores más mencionados fueron Ramtohul, Metha y Cicinelli. Ellos trabajaron el signo clínico en cuestión y reportaron la experiencia en la atención a los pacientes aquejados con esta enfermedad ocular. El desprendimiento de la capa bacilar de la retina es un signo presente en varias enfermedades asociadas a inflamación del segmento posterior ocular. La tomografía de coherencia óptica de dominio espectral es una técnica efectiva para determinarlo, aunque estos planteamientos aún son escasos en la literatura, lo cual reafirma la importancia científica de continuar los estudios a partir de hipótesis iniciales desde el punto de vista histológico y tomográfico.

Retinal bacillary layer detachment is the separation of the inner segments of the photoreceptors from the rest of the neurosensory retina, or separation between the myode and ellipsoid zone of the retina, which in a recent finding can be identified by spectral-domain optical coherence tomography. The objective is to update the knowledge about the detachment of the bacillary layer of the retina and the use of spectral-domain optical coherence tomography in ocular diseases that are associated with this sign. Bibliographic sources such as academic Google, SciELO LAC, MEDLINE and MEDICARIBE were consulted. Fifty-four documents were retrieved, of which 18 were relevant to this research. The results were limited to the Spanish and English language and to the last five years. The most mentioned authors were Ramtohul, Metha and Cicinelli. They worked on the clinical sign in question and reported the experience in caring for patients afflicted with this ocular disease. Detachment of the bacillary layer of the retina is a sign present in several diseases associated with ocular posterior segment inflammation. Spectral-domain optical coherence tomography is an effective technique to determine it, although it is still scarce in the literature, which reaffirms the scientific validity of continuing studies from initial hypotheses from the histological and tomographic point of view.

Retinal photoreceptor cell damage caused by diabetes through down-regulation of glutathione peroxidase 4 and its mechanism / 中华实验眼科杂志

Objective:To investigate the changes of glutathione peroxidase 4 (GPX4) in retinal photoreceptor cells, and the related mechanism correlated with retinal photoreceptor cell damage.Methods:The posterior segment tissues of 8 age-matched male donors were collected from the Body (Organ) Donation Register and Corneal Receiving Station of Tongji Hospital of Wuhan Red Cross from 2018 to 2021, including 4 non-diabetic donors and 4 diabetic donors.The tissues were divided into diabetes group and control group according to their donors.A total of 14 healthy SPF 8-week-old male C57BL/6 mice were selected and randomly divided into diabetes group and control group by the random number method, with 7 mice in each group.The mice in diabetes group were intraperitoneally injected with streptozotocin at a dose of 50 mg/kg for 5 days, and no intervention was given to mice in control group.Mouse photoreceptor cells 661W were divided into advanced glycation end products (AGEs) group and control group.AGEs group was treated with 100 μg/ml AGEs for 24 hours to simulate diabetic injury, and no intervention was given to control group.The outer segment morphology of retinal photoreceptors in human and mouse retinas was observed by hematoxylin-eosin staining.The expressions of glial fibrillary acidic protein (GFAP), rhodopsin and GPX4 in human and mouse retinas were detected by immunofluorescence staining.The expressions of GFAP, rhodopsin and GPX4 in mouse retina and the expression of GPX4 in 661W cells were determined by Western blot.The activity of 661W cells was detected by cell counting kit-8 (CCK8) method.The concentration of malondialdehyde (MDA) in mouse retina and cells was detected by TBA method.The activity of superoxide dismutase (SOD) in mouse retina and cells was detected by hydroxylamine assay.The use of human tissues was approved by the Ethics Committee of Tongji Hospital, Tongji Medical College of Huazhong University of Science and Technology (No.TJ-C20230301). The animal experiments were conducted with reference to the Standards Guide for the Care and Use of Laboratory Animals of the National Institutes of Health, and the study protocol was approved by the Experimental Animal Ethics Committee of Tongji Hospital, Tongji Medical College of Huazhong University of Science and Technology (No.TJH-2016001).Results:Hematoxylin-eosin staining showed that retinal photoreceptor outer segments were deformed or broken in diabetic donors and diabetic mice compared with control groups.GFAP fluorescent signal mainly appeared in the inner retina of human and mice, and the stained cells were spindle or polygonal, which was consistent with the shape of glial cells.The retinal GFAP fluorescent signal of diabetic tissue and mouse groups was stronger than that of respective control groups.Rhodopsin was only expressed in the outer segment layer of photoreceptors with clear boundaries, and GPX4 was expressed in the whole retina with strong signal in the outer segment layer of photoreceptors.The fluorescent signals of rhodopsin and GPX4 in diabetic tissue and mouse groups were weaker than those in respective control groups.The relative expressions of GFAP were significantly higher and the relative expressions of rhodopsin and GPX4 were significantly lower in diabetic tissue and mouse groups than in respective control groups (all at P<0.05). The cell viability of AGEs group was significantly lower than that of control group ( t=13.490, P<0.001). The relative expression of GPX4 protein in AGEs group was 0.42±0.12, which was significantly lower than 1.00±0.04 in control group ( t=9.041, P<0.001). MDA concentration was higher and SOD activity was lower in retinal tissue of diabetic mice and AGEs group than those in respective control groups, and the differences were statistically significant (all at P<0.05). Conclusions:Diabetes can reduce the GPX4 level in retinal photoreceptor cells and cause the imbalance of oxidation-antioxidant system, which may be the mechanism of the damage to retinal photoreceptor cells caused by diabetes.

Inhibitory effect of blue light intervention on lens-induced myopia development in guinea pigs and the mechanism of cone density change / 中华实验眼科杂志

Objective:To observe the effects of blue light intervention on the development of optical defocus-induced myopia in guinea pigs and investigate its underlying mechanisms.Methods:Forty-eight normal-grade two-week-old tricolor guinea pigs were randomly divided into a blue light group and a white light group, with 24 animals in each group.The right eye of guinea pigs was fitted with a -5.00 D lens to establish an optical defocus model as the experimental eye, while the left eye served as the control without any covering.Before the experiment and after 8-week intervention, the refractive power of guinea pigs was measured by streak retinoscopy.The anterior chamber depth, lens thickness, and axial length were measured by A-scan ultrasonography.Corneal curvature radius was determined using a keratometer.After 8-week intervention, the guinea pigs were euthanized through overanesthesia, and the right eyeballs were enucleated and the retinas were isolated.The density of S and M cone cells of the guinea pig retinal sections were observed via immunofluorescence staining.The expression of retinal retinoic acid was assessed by high-performance liquid chromatography.The expressions of retinoic acid receptor (RAR-β) in the retina and matrix metalloproteinase-2 (MMP-2), tissue inhibitor of metalloproteinase-2 (TIMP-2), and type Ⅰ collagen in the sclera were detected by real-time fluorescence quantitative PCR.Changes in scleral thickness were observed through hematoxylin-eosin staining.The use and care of the animals complied with Regulations for the Administration of Affair Concerning Experimental Animals by State Science and Technology Commission.The study protocol was approved by the Ethics Committee of Eye and ENT Hospital of Fudan University (No.2022ETKLD10032).Results:After 8 weeks of intervention, guinea pigs in the blue light group showed (0.63±0.12)D of relative hyperopia and a deceleration of axial elongation by (0.08±0.00)mm compared with the white light group in the right eye.In the left eye, guinea pigs in the blue light group showed (0.42±0.09)D of relative hyperopia and a deceleration of axial elongation by (0.08±0.00)mm compared with the white light group.The guinea pigs in blue light group showed (1.52±0.09)D of myopia in the right eye compared with the left eye, with an increase in axial elongation of (0.06±0.00)mm.The guinea pigs in white light group showed (1.66±0.07)D of myopia in the right eye compared with the left eye, with an increase in axial elongation of (0.13±0.00)mm, and the differences were statistically significant (all at P<0.05). The density of M cone cells was lower and density of S cone cells was higher in the blue light group in the dorsal and ventral sides of the retinal sections compared with the white light group, showing statistically significant differences ( t=32.33, 52.23, 42.09, 25.02; all at P<0.05). The deceleration of myopia progression in the blue light group was strongly positively correlated with the increase in S cone cell density on the ventral side ( r=0.95, P<0.01). The expression levels of retinoic acid, RAR-β, and MMP-2 were decreased, and expression levels of TIMP-2 and type Ⅰ collagen were increased in blue light group compared with the white light group, showing statistically significant differences ( t=18.73, 7.45, 3.72, 6.19, 9.03; all at P<0.05). The scleral thickness in the blue light group was (125.0±7.8)μm, which was significantly thicker than (102.0±6.3)μm in the white light group ( t=26.93, P<0.05). Conclusions:Blue light intervention can inhibit the progression of defocus-induced myopia in guinea pigs.Refractive power changes in guinea pigs may be influenced by alterations in retinal cone cell density, retinoic acid expression, and scleral collagen expression.

Conception and features of bacillary layer detachment / 中华实验眼科杂志

The separation of outer retinal photoreceptors in patients with toxoplasmosis chorioretinitis was first named bacillary layer detachment (BALAD), which was manifested as a split at the level of the photoreceptor inner segment myoid creating a distinctive intraretinal cavity in optical coherence tomography.Subsequently BALAD has been reported by many researchers in different diseases.In the outer retina, the myoid is a relatively weak structure in photoreceptor inner segment.When the outward force that promotes the attachment of the photoreceptor outer segment to the retinal pigment epithelium exceeds the tensile strength of the photoreceptor inner segment myoid, the myoid zone splits and BALAD occurs.BALAD has its unique multimodal imaging characteristics, and the identification of it can provide a new idea for the diagnosis, detection and treatment of ocular diseases.This paper reviewed the development of BALAD nomenclature, its anatomical structure, pathophysiological mechanism and multimodal image features.

Research progress of autophagy in retinal and eye diseases / 国际眼科杂志(Guoji Yanke Zazhi)

Maintaining the homeostasis of intracellular components degradation and recycling, autophagy is a critical control mechanism of cellular quality. It promotes the degradation of cell components to provide nutrients and energy for cellular metabolism in stress response. The retina is a light-sensitive tissue that transduces and processes visual images in the eye, and it has a high demand for substances and energy. Basal autophagy is essential for holding retinal homeostasis and the normal function of the visual system. Therefore, the latest studies that investigating the participation of autophagy in eye diseases such as glaucoma, age-related macular degeneration, diabetic retinopathy, retinal dystrophies, and retinal detachment were summarized, providing a theoretical basis for the future treatment of eye diseases by regulating autophagy.

Effect of metformin on the polarization status of microglia and photoreceptor cells activity in a high glucose environment / 中华眼底病杂志

Objective:To observe the effect of metformin on the polarization state and photoreceptor cell activity of microglia (BV2 cells) in a high glucose environment.Methods:An experimental study. BV2 cells were divided into a control group, a high glucose group, and a metformin+high glucose group. The cells in the high glucose group were cultured with 75 mmol/L glucose in the medium; the cells in the metformin+high glucose group were pretreated with 2 mmol/L metformin for 12 h and then placed in 75 mmo/L glucose concentration medium. The relative expression of M1 marker inducible nitric oxide synthase (iNOS), CD86 and M2 markers arginase 1 (Arg-1), and CD206 protein were detected by Western blot. Interleukin (IL)-6, tumor necrosis factor (TNF)-α, IL-4 were detected by enzyme-linked immunosorbent assay (ELISA). BV2 cells were co-cultured with mouse retinal photoreceptor cells (661W cells) for 24 h. The proliferation rate of 661W cells in each group was measured by methyl thiazolyl tetrazolium (MTT) colorimetric assay; the apoptosis rate of 661W cells in each group was measured by flow cytometry and terminal-deoxynucleoitidyl transferase mediated nick end labeling (TUNEL). An independent sample t-test was used for comparison between groups. Results:Western blot assay showed that the relative expression of iNOS and CD86 protein was increased and the relative expression of Arg-1 and CD206 protein was decreased in BV2 cells in the high glucose group compared with the control group, and the differences were all statistically significant ( t=-16.783, -11.605, 4.325, 4.649; P<0.05); compared with the high glucose group, the relative expression of iNOS and CD86 protein was decreased and the relative expression of Arg-1 and CD206 protein was increased in BV2 cells in the metformin + high glucose group compared with the high glucose group, and the differences were all statistically significant ( t=7.231, 5.560, -8.035, -8.824; P<0.01). ELISA results showed that compared with the control group, the BV2 cells in the high glucose group had increased IL-6, TNF-α content and IL-4 content was decreased in BV2 cells in the high glucose group compared with the control group, and the differences were all statistically significant ( t=-64.312, -127.147, 71.547; P<0.001); compared with the high glucose group, IL-6 and TNF-α content was significantly decreased and IL-4 content was significantly increased in BV2 cells in the metformin+high glucose group, and the differences were all statistically significant ( t=44.426, 83.232,-143.115; P<0.001). After co-culture of BV2 cells with 661W cells for 24 h, the results of MTT colorimetric assay showed that compared with the control group, the activity of 661W cells in the high glucose group was significantly reduced, and the difference was statistically significant ( t=7.456, P<0.01); compared with the high glucose group, the activity of 661W cells in the metformin+high glucose group was increased ( t=-3.076, P<0.05). TUNEL method and flow cytometry showed that the apoptosis rate of 661W cells in the high glucose group was significantly higher compared with the control group, and the differences were both statistically significant ( t=-22.248, -22.628; P<0.001); compared with the high glucose group, the apoptosis rate of 661W cells in the metformin+high glucose group was significantly decreased, and the difference was statistically significant ( t=11.767, 6.906; P<0.001, 0.01). Conclusion:In the high glucose environment, metformin inhibited the inflammatory response and attenuated the apoptosis of photoreceptor cells by regulating the polarization of microglia toward the M2 type.

Role of M2 isoform of pyruvate kinase in diabetic retinopathy / 国际眼科杂志(Guoji Yanke Zazhi)

@#Diabetic retinopathy(DR), one of the most common diabetes-specific microvascular complications, is classically described by intraretinal microvascular abnormalities and neovascularization. It is the main reason why visual impairment and blindness in people aged 20-65 years worldwide. Glycolysis can provide energy by converting glucose into pyruvate. Endothelial cells mainly utilize glycolysis to produce ATP to maintain the function, including forming tight junctions and barrier functions. Pyruvate kinase(PK)M2(M2 isoform of pyruvate kinase)is a key enzyme of glycolysis and is widely expressed in most tissues. As major cellular components in the retina, endothelial cells and photoreceptor cells play a crucial role in the occurrence and development of DR. Studies have shown that PKM2 takes part in the development of DR by regulating the function of endothelial cells and photoreceptors in metabolic and non-metabolic ways. Therefore, this article overviews the role of PKM2 in DR from the direction of endothelial cells and photoreceptor cells and provides new insight into the diagnosis and treatment of DR.

Protective Effects of Anthocyanins Extracted from Vaccinium Uliginosum on 661W Cells Against Microwave-Induced Retinal Damage / 中国结合医学杂志

OBJECTIVE@#To study the protective effect of anthocyanins extracted from Vaccinium Uliginosum (VU) on retinal 661W cells against microwave radiation induced retinal injury.@*METHODS@#661W cells were divided into 6 groups, including control, model [661W cells radiated by microwave (30 mW/cm2, 1 h)] and VU groups [661W cells pretreated with anthocyanins extracted from VU (25, 50, 100 and 200 µg/mL, respectively) for 48 h, and radiated by microwave 30 mW/cm2, 1 h]. After treatment with different interventions, the cell apoptosis index (AI) was determined using Heochst staining; contents of malonaldehyde (MDA), glutataione (GSH), and activity of superoxide dismutase (SOD) were measured. mRNA expressions of nuclear factor erythroid 2-related factor 2 (Nrf2) and heme oxygenase 1(HO-1) were detected by real time quantitative polymerase chain reaction, and the expression of HO-1 protein was examined by Western blot analysis. Nucleus and cytoplasm were separated and Nrf2 protein expression was further verified by Western blot analysis.@*RESULTS@#There was significant difference in AI among the groups (F=322.83, P<;0.05). Compared with the control group, AI was significantly higher in the model group and was lower in 4 VU-pretreated groups (P<;0.05). Linear regression analysis showed the decline of AI was in a dose-dependent manner with VU treatment (r=0.8419, P<;0.05). The MDA and GSH contents of 661W cells in VU-treated groups were significantly lower than the model group (P<;0.05). Compared with the model group, the SOD activity in the VU-treated groups (50, 100 and 200 µg/mL) was significantly higher (all P<;0.05). The Nrf2 and HO-1 mRNA expressions were slightly increased after irradiation, and obviously increased in 100 µg/mL VU-treated group. After irradiation, the relative expressions of HO-1 and Nrf2 proteins in nucleus were slightly increased (P<;0.05), and the changes in cytoplasm were not obvious, whereas it was significantly increased in both nucleus and cytoplasm in the VU treatment groups.@*CONCLUSIONS@#Anthocyanins extracted from VU could reduce apoptosis, stabilize cell membrane, and alleviate oxidant injury of mouse retinal photoreceptor 661W cells. The mechanism might be through activating Nrf2/HO-1 signal pathway and inducing HO-1 transcription and translation.

Acute retinal pigment epitheliitis: a case presentation and literature review / Epitelite pigmentar retiniana aguda: apresentação de caso e revisão da literatura

ABSTRACT Acute retinal pigment epitheliitis (ARPE) is an idiopathic, self-limiting inflammatory retinal disorder that particularly affects healthy young individuals. The characteristic fundoscopic appearance of the acute retinal pigment epitheliitis includes a fine pigment stippling surrounded by a yellow-white hypopigmented halos in the macula. Although the exact pathogenesis of the disease remains unknown, some reports have suggested a relationship between a viral infection and acute retinal pigment epitheliitis. Acute retinal pigment epitheliitis is a rare disorder, and only single case reports or case series are found in the literature. The clinical and demographic characteristics of patients with this disease are not fully understood because of its rarity. In this study, we searched the literature to collect clinical and demographic features of the reported cases. We detail the characteristics of acute retinal pigment epitheliitis were pointed and discuss the pathogenesis of the disease.(AU)

RESUMO A epitelite pigmentar retiniana aguda (EPRA) é uma doença inflamatória idiopática e autolimitada da retina, que afeta especialmente indivíduos jovens e saudáveis. À fundoscopia, a aparência característica dessa entidade é de um pontilhado fino do pigmento, cercado de halos hiperpigmentados branco-amarelados na mácula. A patogênese exata da doença ainda é desconhecida, mas alguns relatos apontam uma relação entre epitelite pigmentar retiniana aguda e infecções virais. A epitelite pigmentar retiniana aguda é uma condição rara e na literatura há apenas relatos de casos individuais ou séries de casos. As características clínicas e demográficas da doença não são totalmente compreendidas, devido à sua raridade. Para este relato, foi feita uma busca na literatura para coletar os dados clínicos e demográficos dos casos relatados. Finalmente, são apontadas as características da epitelite pigmentar retiniana aguda e discute-se a patogênese da doença.(AU)

Alteraciones en la visión cromáticas por agentes neurotóxicos en pacientes de 20 a 40 años / Visual chromatic alteration by neurotoxics in patients of 20 ­ 40 age / Alteracao visual cromática por neurotóxicos em pacientes de 20 a 40 anos

El estudio busca determinar las alteraciones de la visión cromática por gentes neurotóxicos en pacientes de 20 a 40 años en la parroquia Checa ­ Ecuador y cuál de ellas genera mayor vulnerabilidad en las células nerviosas fotorreceptoras de la retina. MATERIALES Y MÉTODOS: se realizó un estudio evaluativo - descriptivo de pruebas en donde participaron 54 personas de edades entre 20 a 40 años que pertenecen al programa social bachillerato acelerado y se les aplicó la historia clínica de detección para determinar si están dentro de los criterios de inclusión. A los 54 pacientes que cumplieron con el requisito, a parte del examen visual completo, se les aplicó el test de Farnsworth que es la prueba más certera y completa para el diagnóstico de las distintas alteraciones de la visión cromática. RESULTADOS: al realizar la tabulación de datos, se observa que la alteración cromática más frecuente es la deuteranomalía, y que el agente más neurotóxico para las células fotorreceptoras retinales, es el alcohol, afectando mayormente, a la población masculina de entre 31 a 35 años, el segundo neurotóxico más agresivo, es el cigarrillo, afectando a la misma población. CONCLUSIONES: se determina que los agentes neurotóxicos inciden directamente en el daño de fotorreceptores especializados al color, el daño puede ser imperceptible al principio, pero puede afectar al paciente principalmente en el desarrollo laboral, que es cuando el paciente cae en cuenta que está presentando una alteración cromática, la disminución de la exposición a los mismos, puede revertir el daño si la frecuencia no ha sido prolongada(AU)

The study seeks to determine the alterations of color vision by neurotoxic people in patients aged 20 to 40 years in the Czech parish - Ecuador and which of them generates greater vulnerability in the photoreceptor nerve cells of the retina. MATERIALS AND METHODS: an evaluative-descriptive study of tests was carried out in which 54 people between the ages of 20 and 40 who belong to the accelerated high school social program participated and the clinical history of detection was applied to them to determine if they were within the inclusion criteria. To the 54 patients who fulfilled the requirement, apart from the complete visual examination, the Farnsworth test was applied, which is the most accurate and complete test for the diagnosis of the different color vision alterations. RESULTS: when performing the data tabulation, it is observed that the most frequent chromatic alteration is deuteranomaly, and that the most neurotoxic agent for retinal photoreceptor cells is alcohol, affecting mainly the male population between 31 and 35 years of age. The second most aggressive neurotoxic is cigarettes, affecting the same population. CONCLUSIONS: it is determined that neurotoxic agents directly affect the damage of specialized photoreceptors to color, the damage may be imperceptible at first, but it can affect the patient mainly in work development, which is when the patient realizes that he is presenting a chromatic alteration, decreasing the exposure to them, can reverse the damage if the frequency has not been prolonged.(AU)

O estudo visa determinar as alterações da visão de cores por pessoas neurotóxicas em pacientes de 20 a 40 anos na freguesia checa-Equador e qual delas gera maior vulnerabilidade nas células nervosas fotorreceptoras da retina. MATERIAIS E MÉTODOS: foi realizado um estudo descritivo-avaliativo de testes em que participaram 54 pessoas entre 20 e 40 anos que pertencem ao programa social do ensino médio acelerado e foi aplicado o histórico clínico de detecção para determinar se estavam dentro dos critérios de inclusão. Aos 54 pacientes que preencheram o requisito, além do exame visual completo, foi aplicado o teste de Farnsworth, que é o teste mais preciso e completo para o diagnóstico das diferentes alterações na visão de cores. RESULTADOS: ao realizar a tabulação dos dados, observa-se que a alteração cromática mais frequente é a deuteranomalia, e que o agente mais neurotóxico para as células fotorreceptoras da retina é o álcool, afetando principalmente a população masculina entre 31 e 35 anos. O segundo neurotóxico mais agressivo é cigarros, afetando a mesma população. CONCLUSÕES: é determinado que os agentes neurotóxicos afetam diretamente o dano dos fotorreceptores especializados à cor, o dano pode ser imperceptível a princípio, mas pode afetar o paciente principalmente no desenvolvimento do trabalho, que é quando o paciente percebe que está apresentando uma alteração cromática, diminuindo a exposição a eles pode reverter o dano se a frequência não for prolongada. (AU)

Regulatory effect of edaravone on the photoreceptor autophagy at the early stage of experimental retinal detachment in rats / 中华实验眼科杂志

Objective:To investigate the effect of edaravone, a free radical scavenger, on the regulation of retinal autophagy and the protection of photoreceptor cells at the early stage of experimental retinal detachment (RD) in rats.Methods:Fifty-one adult male Sprague-Dawley rats were used for RD model establishment, and another 24 rats were served as PBS injection group.The RD model was established via subretinal injection of 0.5% sodium hyaluronate into the right eye of the rats and the rats with successful modeling were randomly divided into RD model group and edaravone treatment group.The rats in the edaravone treatment group were given edaravone of 3 mg/kg intraperitoneally, twice a day after modeling, and the rats in the PBS injection group and RD model group were given equal volume of normal saline.Rats were sacrificed on the 1st day, 3rd day and 7th day following modeling.The T-superoxide dismutase (T-SOD) activity and malondialdehyde (MDA) content in the intraocular fluid was detected.The expression levels of superoxide dismutase 2 (SOD2), nuclear factor E2-related factor 2 (Nrf2), autophagy related gene 4 (Atg4), microtubule-associated protein 1 light chain 3B (LC3B) and other proteins in retinal tissue were identified by Western blot analysis.TUNEL staining was performed on paraffin sections of the whole eyeball to analyze the apoptosis of photoreceptor cells.The study protocol was approved by an Ethics Committee of Xi'an Fourth Hospital (No. 2016016). The use and care of animals complied with the Regulations on the Administration of Experimental Animals.Results:The RD area was more than 60% in rat eyes of RD model.There were significant differences in MDA content and T-SOD activity among different groups at various time points (MDA: Fgroup=385.513, P<0.01; Ftime=13.021, P<0.01.T-SOD: Fgroup=48.865, P<0.01; Ftime=7.700, P=0.003). Compared with the PBS injection group, the MDA concentration was significantly increased and the T-SOD activity was significantly decreased in the RD group and edaravone treatment group on the 1st, 3rd and 7th day after modeling (all at P<0.05). The MDA concentration was significantly reduced and the T-SOD activity was significantly elevated in the edaravone treatment group on the 1st, 3rd and 7th day after modeling in comparison with those of the RD group (all at P<0.05). Compared with the PBS injection group, the relative expression levels of SOD2 and Nrf2 proteins were significantly increased in the RD group and edaravone treatment group on the 1st, 3rd and 7th day after modeling (all at P<0.05), and Atg4 and LC3B-Ⅱ/LC3B-Ⅰ were significantly increased on the 1st, 3rd and 7th day after modeling (all at P<0.05). The expression level of SOD2 in the edaravone treatment group was significantly higher than that in the RD group on the 1st, 3rd and 7th day after modeling (all at P<0.05), and the expression level of Nrf2 was significantly increased in the edaravone treatment group on the 1st and 3rd day after modeling compared with that of the RD group (both at P<0.05), and the expression levels of Atg4 and LC3B-Ⅱ/LC3B-Ⅰ were significantly increased in the edaravone treatment group on the 3rd day after modeling in comparison with those of the RD group (both at P<0.05). No significant TUNEL positive cells were observed in PBS injection group at all time points, and TUNEL positive cells were observed on the 1st, 3rd and 7th day after modeling in the RD group, and the expression level of caspase-3 in the RD group was significantly increased in comparison with that of the PBS injection group ( P<0.05). The apoptosis of photoreceptor cells and the expression level of caspase-3 in edaravone treatment group were significantly decreased in comparison with those of the RD group on the 1st, 3rd and 7th day after modeling (all at P<0.05). Conclusions:The intraperitoneal injection of edaravone, twice a day, can significantly improve the antioxidant capacity of the retina after experimental RD in rats, regulate retinal autophagy and reduce the apoptosis of photoreceptor cells in early-stage RD.

Relationship between irradiation time of riboflavin-ultraviolet A scleral collagen cross-linking and retinal injury / 中华实验眼科杂志

Objective:To investigate the effects of riboflavin-ultraviolet A scleral collagen cross-linking on the retina under different irradiation time, and to determine the safe irradiation time.Methods:Sixty healthy New Zealand white rabbits were randomly divided into control group (0 minute group), 10 minutes group, 20 minutes group, 30 minutes group and 40 minutes irradiation group according to the irradiation time, with 12 rabbits in each group.The left eye was irradiated with riboflavin-ultraviolet A scleral collagen (370 nm, 10 mW/cm 2). The histopathological change of retina was observed by light microscope and transmission electron microscope and compared among different groups.The concentration of MDA and the activities of SOD, CAT and GSH-Px in retinal tissue were detected by corresponding kits.The expression levels of SOD and CAT proteins in retinal tissue were detected by Western blot method.The study protocol was approved by the Binzhou Medical University Laboratory Animal Ethical Committee (No.2017-80). The use and care of animals complied with the statement of ARVO and the Regulation on the Management of Laboratory Animal Quality of China. Results:Under the light microscope, the structure of the retinas in the control group was orderly arranged.Under the transmission electron microscope, the lamellar structure in the inner segment and the mitochondrial structure in the outer segment of the photoreceptor cells were intact, and the mitochondrial ridge was continuous in the control group.There was no obvious difference in retinal morphology between the 10 minutes irradiation group and the control group under both the light microscope and the transmission electron microscope, and the retinal damage became more severe with the prolongation of irradiation time.The concentration of MDA in the retina of each group was elevated gradually with the increase of irradiation time, and the difference was statistically significant ( F=65.25, P<0.05). The concentration of MDA was (11.31±1.84), (14.94±1.04)and (18.25±1.42)nmol/mgprot in the 20 minutes, 30 minutes and 40 minutes irradiation groups respectively, which were significantly higher than (1.13±0.02)nmol/mgprot in the control group (all at P<0.05). The MDA concentration in 20 minutes, 30 minutes and 40 minutes irradiation groups was increased successively, showing statistically significant differences (all at P<0.05). With the prolongation of irradiation time, the activities of SOD, CAT and GSH-Px as well as the expression levels of SOD and CAT proteins were significantly decreased gradually ( F=44.09, 34.18, 35.60, 115.75, 78.86; all at P<0.05). The differences between the control group and 20 minutes, 30 minutes, 40 minutes irradiation groups, and the differences among 20 minutes, 30 minutes, 40 minutes irradiation groups were statistically significant (all at P<0.05). Conclusions:Riboflavin-ultraviolet A 10 mW/cm 2 scleral collagen cross-linking irradiation for 10 minutes is safe.Excessive irradiation time can cause damage to the retina of rabits.

Photoreceptor cell replacement therapy for retinal degeneration diseases / 中国组织工程研究

BACKGROUND: There is no effective treatment for retinal degenerative diseases, among which the loss of photoreceptor cells, dysfunction and loss of photoreceptor cells are the main causes of retinal degenerative diseases. Photoreceptor cell transplantation as a promising cell replacement therapy is the main research direction today. OBJECTIVE: To review the progress of photoreceptor cell replacement in the treatment of retinal degeneration. METHODS: PubMed, CNKI and Wanfang databases were searched. The Chinese keywords were “photoreceptor cells, retina, transplantation” and the English keywords were “photoreceptors, retina, transplantation”. After preliminary screening by reading the titles and abstracts, the articles with low relevance to the subject were excluded, and a total of 62 articles were finally included for review. RESULTS AND CONCLUSION: The transplantation of exogenous cells into the retinal degeneration environment to replace the photoreceptors lost in advanced retinal degeneration has shown great advantages and provided a new therapeutic strategy for the diseases of retinal degeneration. However, standardized cell screening protocols for clinical use are still not perfect, which is an important challenge for future research.

Research progress of photoreceptor transplantation in retinal degenerative diseases / 国际眼科杂志(Guoji Yanke Zazhi)

@#Retinal degenerative disease is a major disease that affects human vision. It damages human photoreceptor cells and damages human vision. And the mammalian retina does not have the ability to regenerate, once the disease will seriously affect people's normal life. At present, there is no clear way to prevent and alleviate these diseases, but the transplantation of photoreceptors to supplement the damaged photoreceptors in the retina can treat retinal diseases. In this paper, we will discuss the current situation and techniques of photoreceptor transplantation to restore vision in retinal degenerative diseases.

Hipertensión ocular asociada al desprendimiento de la retina regmatógeno / Ocular hypertension associated to rhegmatogenous retinal detachment

Objetivo: Describir el comportamiento de la hipertensión ocular asociada al desprendimiento de la retina regmatógeno. Métodos: Se realizó un estudio observacional descriptivo de corte longitudinal retrospectivo de una serie de casos atendidos en la consulta de Vítreo-Retina del Instituto Cubano de Oftalmología "Ramón Pando Ferrer" en el período comprendido de mayo del año 2016 a diciembre de 2019. Se estudiaron 7 ojos de 7 pacientes. Se utilizaron las siguientes variables: edad, sexo, antecedentes patológicos oculares, tiempo de evolución de la disminución de la visión, tensión ocular, tipo de rotura retinal, cirugía de retina realizada y tratamiento antihipertensivo ocular. Resultados: Predominó el sexo masculino, con un promedio de edad de 27,2 años. La mayoría de los pacientes tuvieron rotura retinal en el cuadrante nasal superior y todos en extrema periferia. Todos los pacientes tuvieron la presión intraocular antes de la cirugía por encima de 30 mmHg. A todos se le indicó tratamiento hipotensor tópico y se les realizó cirugía convencional. Con diferentes fluctuaciones de la presión intraocular posterior a la cirugía, todos los pacientes normalizaron la tensión ocular y mantuvieron la retina aplicada. Conclusiones: El diagnóstico correcto de este síndrome puede ofrecer dificultad porque los signos de una condición pueden enmascarar los de otra. El reconocimiento de la entidad puede ser más fácil si el oftalmólogo tiene en mente que estas entidades pueden aparecer juntas. De esta forma, se hace un diagnóstico y un tratamiento certero que evite la discapacidad visual por esta causa(AU)

Objective: Describe the behavior of ocular hypertension associated to rhegmatogenous retinal detachment. Methods: An observational retrospective longitudinal descriptive study was conducted of 7 eyes of 7 patients attending the Vitreous-Retina Service at Ramón Pando Ferrer Cuban Institute of Ophthalmology from May 2016 to December 2019. The variables considered were age, sex, ocular pathological antecedents, time of evolution of vision reduction, ocular tension, type of retinal tear, retinal surgery performed and ocular hypertension treatment. Results: A predominance was found of the male sex, with a mean age of 27.2 years. Most of the patients had retinal tear in the upper nasal quadrant, and all in the extreme periphery. In all cases, intraocular pressure was above 30 mmHg before surgery. All patients were indicated topical hypotensive treatment and underwent conventional surgery. With different intraocular pressure fluctuations after surgery, all patients normalized their ocular tension and retained the retina applied. Conclusions: Correct diagnosis of this syndrome may be difficult to achieve, since the signs of one condition may mask those of another. Identification may be easier if the ophthalmologist bears in mind that these diseases may occur together. An accurate diagnosis may thus be made and an effective treatment indicated which will prevent visual disability due to this cause(AU)

Flavonoid Luteolin Enhances Calcium Overload in Mouse Photoreceptors

Background Calcium overload is one of the main reasons that cause photoreceptor apoptosis during theirdegeneration. Our recent data show that flavonoid luteolin protects mouse retinal photoreceptors in diseasedmodel. Aim To explore how luteolin affects the calcium overload in mouse retinal photoreceptors. Methods Fluo4 AM was loaded into retinal slices of wild type mice. Fluorescent images were taken every 5s to monitor thechanges of calcium signal in the soma of photoreceptor. Tissue was perfused with Ringer’s solution as control,then luteolin for 10 min and then Ringer’s as washout. During the perfusion of each solution, high K+ solution wasapplied to elicit calcium overload in photoreceptors. Fluorescent intensity of the photoreceptor soma wasmeasured and compared between control and luteolin solution. Results The high K+ induced-peak fluorescentintensity of Fluo-4 after luteolin treatment was significant higher than that perfused with control solution.Conclusion Luteolin enhances calcium overload in mouse retinal photoreceptors.

Spontaneous outer retinal layer recovery in a case of hypertensive choroidopathy secondary to pre-eclampsia: a multimodal evaluation / Recuperação espontânea das camadas externas da retina em um caso de coroidopatia hipertensiva secundária a pré-eclâmpsia: avaliação multimodal

ABSTRACT A 26-year-old woman presented at 28 weeks gestation with hypertensive choroidopathy associated with pre-eclampsia. Fundus photography, fundus autofluorescence, spectral-domain optical coherence tomography (SD-OCT), fluorescein angiography, and indocyanine green angiography were performed in both eyes in the immediate postoperative period. SD-OCT images were obtained before delivery and during a 3-month follow-up. Fundus autofluorescence exhibited patchy hyper- and hypoautofluorescent lesions; fluorescein and indocyanine green angiography revealed areas of choroidal ischemia; and SD-OCT showed disorganization of the outer retinal layers and disruption of the ellipsoid zone. After her blood pressure was stabilized, progressive recovery of the outer retinal layer was monitored on SD-OCT.

RESUMO Uma mulher de 26 anos de idade, com 28 semanas de gestação apresentando coroidopatia hipertensiva associada à pré-eclâmpsia. Retinografia, autofluorescência, tomografia de coerência óptica de domínio espectral, angiofluoresceínografia e angiografia com indocianina verde foram realizadas em ambos os olhos no período pós-operatório imediato do parto. Imagens da tomografia de coerência óptica de domínio espectral foram obtidas antes do parto e durante o seguimento de 3 meses. A autofluorescência apresentou lesões heterogêneas hiper e hipoautofluorescentes, a angiofluoresceínografia e angiografia com indocianina verde revelaram áreas de isquemia de coroide, e a tomografia de coerência óptica de domínio espectral apresentou desorganização das camadas externas da retina e interrupção da zona elipsóide. Após a estabilização da pressão sanguínea, a recuperação progressiva da camada externa da retina foi monitorada pela tomografia de coerência óptica de domínio espectral.

Focus on stem cell-based therapy for retinal degenerative diseases / 中华实验眼科杂志

Retinal degenerative diseases are the common cause of blindness for all ages.Cell replacement therapy is the main strategy for treating retinal degenerative diseases.Recently, several retinal pigment epithelium(RPE) transplantation clinical trials have taken place worldwide and greatly enhanced the visual function of patients.However, irreversible loss of photoreceptors has been found in the late stage of diseases.Thus, photoreceptor transplantation is essential for the treatment of late-stage retinal degenerative diseases.How to obtain the clinical-grade amount of human cone photoreceptors remains to be one of the technical obstacles.This review introduced the present clinical trials of RPE transplantation and research achievements of photoreceptor transplantation.Furthermore, we will focus on the studies of stem cell-derived human photoreceptor differentiation.Lastly, the difficulties and future directions of stem cell-based therapy for retinal degenerative diseases will be discussed.

Mechanism and protection of retina injured by blue light / 国际眼科杂志(Guoji Yanke Zazhi)

@#Blue light is an important part of natural light.The wavelength is mainly between 400nm and 500nm, which is a kind of short-wavelength light and a part of the high-energy visible spectrum. The damage of blue light refers to the photochemical action caused by radiation of this wavelength, resulting in damage to the retina. In the visible light, blue light has the highest sensitivity to the retina and the strongest penetrating power, so the photochemical damage is the strongest. The primary harm is to damage retinal pigment epithelium(RPE)and retinal photoreceptor cells. The research on the protection against the damage of blue light has been gradually carried out. In this paper, the research progress of its protective mechanism is discussed based on the currently study.