Epigenetic modifications such as DNA methylation, histone post-translational modifications, non-coding RNA are reversible, heritable alterations which are induced by environmental stimuli. Major risk factors of diabetes and diabetic complications including hyperglycemia, oxidative stress and advanced glycation end products, can lead to abnormal epigenetic modifications in retinal vascular endothelial cells and retinal pigment epithelium cells. Epigenetic mechanisms are involved in the pathogenesis of macular edema and neovascularization of diabetic retinopathy (DR), as well as diabetic metabolic memory. The heritable nature of epigenetic marks also playsakey role in familial diabetes mellitus. Further elucidation of epigenetic mechanisms in DR can open the way for the discovery of novel therapeutic targets to prevent DR progression.
To perform a meta-analysis of single nucleotide polymorphism needs to calculate gene frequency. This paper employs allele model as an example to introduce how to calculate gene frequency and display the process of a meta-analysis of single nucleotide polymorphism data using Review Manager 5.3 software.
Open-globe injuries (OGI) result in complicated and diverse conditions with different mechanisms and anatomical locations, which lead to completely different outcomes based on when to perform pars plana vitrectomy (PPV) after trauma. The PPV operation time points are generally divided into early (0 - 3 days), delayed (4 - 14 days), and late (> 2 weeks). There are still some controversies about the PPV time points after OGI. Injuries with intraocular foreign bodies or high risk of infection usually need early surgery to reduce the occurrence of endophthalmitis. However corneal edema and vitreous hemorrhage can increase the difficulties for early diagnosis and surgery. If there is choroidal hemorrhage or severe trauma in the back part of the eye, delayed intervention can allow the blood clots to be liquefied and removed easily. But there is higher incidence of postoperative complications. Late surgery can reduce the difficulty of PPV, but the increased incidence of proliferative vitreoretinopathy may lead to severe retinal traction, tears and postoperative scar formation.
Microparticles are small vesicles that are released by budding of the plasma membrane during cellular activation and apoptotic cell breakdown. A spectrum of cell types can release microparticles including endothelial cells, platelets, macrophages, lymphocytes and tumor cells. Biological effects of microparticles mainly include procoagulant activity, inhibition of inflammation and cancer progression. The present study shows that vitreous microparticles isolated from proliferative diabetic retinopathy (PDR) stimulated endothelial cell proliferation and increased new vessel formation, promoting the pathological neovascularization in PDR patients. Oxidative stress induces the formation of retina pigment epithelium-derived microparticles carrying membrane complement regulatory proteins, which is associated with drusen formation and age related macular degeneration. Microparticles from lymphocyte (LMP) play an important role in anti-angiogenesis by altering the gene expression pattern of angiogenesis-related factors in macrophages. Besides, LMP are important proapoptotic regulators for retinoblastoma cells through reduction of spleen tyrosine kinase expression and upregulation of the p53-p21 pathway which ultimately activates caspase-3. However, how to apply the microparticles in the prevention and treatment of retinal diseases is a major challenge, because the study of the microparticles in the fundus diseases is still limited. Further studies conducted would certainly enhance the application of microparticles in the fundus diseases.
The most important difference between systematic review and traditional narrative review lies in their respective quality, namely the degree of bias control. Generally speaking, the sources of bias include the process of literature searching, study selection, data extraction and original studies. A systematic review may greatly reduce bias, as it takes effective steps such as developing search strategies, undertaking funnel plot analysis, using established criteria for study selection, and assessment of the methodology quality of studies. All these help to control, identify and, describe the possible bias.
Retinal degeneration mainly include age-related macular degeneration, retinitispigmentosa and Stargardt’s disease. Although its expression is slightly different, its pathogenesis is photoreceptor cells and/or retinal pigment epithelial (RPE) cel1 damage or degeneration. Because of the 1ack of self-repairing and renewal of retinal photoreceptor cells and RPE cells, cell replacement therapy is one of the most effective methods for treating such diseases.The stem cells currently used for the treatment of retinal degeneration include embryonicstem cells (ESC) and various adult stem cells, such as retinal stem cells (RSC), induced pluripotent stem cells (iPSC). and mesenchyma1 stem cells (MSC). Understanding the currentbasic and clinical application progress of ESC, iPSC, RSC, MSC can provide a new idea for the treatment of retinal degeneration.
In the expert consensus published by the Pediatrics in 2013, it was first proposed that anti-VEGF drugs can be considered for retinopathy of prematurity (ROP) with stage 3, zone Ⅰ with plus disease. However, there are many problems worth the attention of ophthalmologists, including the advantages and disadvantages of anti-VEGF therapy compared with traditional laser therapy, systemic and ocular complications after anti-VEGF therapy, and what indicators are the end points of anti-VEGF therapy. Combined with this consensus and numerous research findings, we recommend that the first treatment for anti-VEGF or laser therapy should be considered from disease control effects. For the threshold and pre-threshold lesions, the effect of anti-VEGF therapy for zoneⅡ lesions is better than that for zone Ⅰ lesions and the single-time effective rate is high. So, it is suggested that anti-VEGF therapy should be preferred for the first treatment. The choice of repeat treatment should be considered from the final retinal structure and functional prognosis. Laser therapy is advisable for the abnormal vascular regression slower and abnormalities in the posterior pole. It can reduce the number of reexaminations and prolong the interval between re-examinations. However, the premature use of laser has an inevitable effect on peripheral vision field. Excluding the above problems, supplemental therapy can still choose anti-VEGF therapy again. Most of the children with twice anti-VEGF therapy are sufficient to control the disease. Anti-VEGF therapy should be terminated when there are signs such as plus regression, threshold or pre-threshold lesions controlled without recurrence, peripheral vascularization, etc.
As most patients of central serous retinopathy (CSC), the symptoms of acute onset will alleviate by oneself after 4-6 months. About 30%-50% of patients with CSC experience chronic or recurrent cases. Resulting in persistent neurosensory detachments and subretinal fluid, causing significant vision loss. Mineralocorticoid receptor (MR) is a kind of nuclear hormone receptors, plays a role in theregulation of water and electrolyte balance. Excessive MR signaling is associated with many diseases. Study found that MR antagonists decreased the thickness of the retina and improved in vision, there was no serious adverse reactions during the period of treatment for chronic CSC. Initial dose of MR antagonists was 25 mg per day, 1 week later, dosage was increased to 50 mg per day, and treatment for about 3 months. There is no conclusive effective treatment and the dosage are still unknown. MR antagonists may be a safe and effective way to treat chronic CSC, though evidence is scant. Prospective, multicenter, large-scale trials is required.
Ophthalmic imaging examination is the main basis for early screening, evaluation and diagnosis of eye diseases. In recent years, with the improvement of computer data analysis ability, the deepening of new algorithm research and the popularization of big data platform, artificial intelligence (AI) technology has developed rapidly and become a hot topic in the field of medical assistant diagnosis. The advantage of AI is accurate and efficient, which has great application value in processing image-related data. The application of AI not only helps to promote the development of AI research in ophthalmology, but also helps to establish a new medical service model for ophthalmic diagnosis and promote the process of prevention and treatment of blindness. Future research of ophthalmic AI should use multi-modal imaging data comprehensively to diagnose complex eye diseases, integrate standardized and high-quality data resources, and improve the performance of algorithms.
Angiopoietin-like protein (ANGPTL), a group of secreted glycoproteins, is widely expressed in vivo and is involved in many pathophysiological processes such as glycolipid metabolism, stem cell growth, local inflammation, vascular leakage and angiogenesis. Many kinds of ANGPTL are closely related to the occurrence and development of diabetic retinopathy (DR), especially ANGPTL4, which has gradually become a new hotspot in the field of DR Research. ANGPTL is involved in glucose metabolism and lipid metabolism, promotes increased vascular permeability, pathological angiogenesis, and participates in intraocular inflammation. ANGPTL is a promising molecular target. It can not only be used as a biomarker to predict the occurrence and progression of DR, but also provide new ideas for the treatment of DR by making antibody drugs to interfere with this molecule.