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.
Idiopathic macular hole (IMH) refers to full thickness defects of retina in macular area with no clear reasons. The management of IMH includes vitrectomy combined with internal limiting membrane (ILM) peeling and pharmacological vitreolysis. But ILM peeling may damage the inner retina; novel techniques, such as inverted ILM flap technique and foveola non-peeling ILM surgery, autologous ILM transplantation had made the method of ILM peeling more diversified with less damage. Pharmacological vitreolysis targeting fibronectin and laminin is considered to work in a two-step mechanism, involving both vitreoretinal separation and vitreous liquefaction. Furthermore, IMH judgment and prognosis indicators like ellipsoid zone, macular hole index, hole formation factor, diameter hole index and tractional hole index based on spectral domain optical coherence tomography enriched the assessment of macular hole diameter, depth and shape. How to make full use of new interventions to reduce the incidence of macular hole and obtain a better visual acuity with closed holes is an important direction for future research.
Noninfectious uveitis refers to a category of inflammatory diseases involving the uvea, with the exception of infectious factors or masquerade syndrome. The diagnosis and follow-up of noninfectious uveitis that involving retina or choroid require fundus imaging techniques. Fundus autofluorescence is a noninvasive imaging technique. Compared with fundus colorized photography, fundus fluorescein angiography and indocyanine green angiography, fundus autofluorescence indicates the functional status of retinal pigment epithelium and photoreceptor cells in a better way, thus playing a role in the pathophysiological mechanisms investigating, early diagnosis, disease progression monitoring and prognosis estimating of noninfectious uveitis, such as Vogt-Koyanagi-Harada disease, Behçet disease, multifocal choroiditis, punctate inner choroidopathy, birdshot chorioretinopathy, multiple evanescent white dot syndrome, acute zonal occult outer retinopathy, acute posterior multifocal placoid pigment epitheliopathy and serpiginous choroiditis.
The suprachoroidal space is a potential space between the sclera and choroid. Suprachoroidal spacedrug delivery is becoming an applicable method to the ocular posterior segment diseases. Because it targets the choroid, retinal pigment epithelium and retina with high bioavailability and safety, while maintaining low levels elsewhere in the eye. In recent years, new discoveries has been carried out in different areas of interest, such as drug delivery methods, pharmacokinetics and clinical trials. Clinical trials with suprachoroidal space injection of triamcinolone acetonide are executed with promising findings for patients with noninfectious uveitis and diabetic macular edema. Suprachoroidal space triamcinolone acetonide injectable suspension is the first and currently the only agent specifically approved for uveitic macular edema by Food and Drug Administration. Nowadays, many clinical trails with suprachoroidal space drug delivery have been explored, although there are still many risks and uncertainties. With the development of technology in the future, suprachoroidal space drug delivery appears to be a promising treatment modality for ocular posterior segment diseases.
Objective To evaluate the effect and safety of Yinzhihuang injection for icteric viral hepatitis. Methods We searched MEDLINE (1966 to 2005), The Cochrane Library (Issue1, 2005), CBMdisk (1978 to 2004), CMCC (1994 to 2005), CMAC (1994 to 2005), CNKI (1994 to 2005), VIP (1989 to 2004). Data were extracted by two reviewers using a designed extraction form. The quality of included trials was critically assessed. RevMan 4.2.7 was used for data analysis. Results Four randomized controlled trials were included. It showed that Yinzhihuang injection could abate jaundice better than or the same as controlled western medicine in patients with hepatitis (WMD 19.70, 95%CI 32.69 to 6.71 and WMD 1.27, 95%CI 3.08 to 0.54, respectively), but less than S-adeanosyl methionine in patients with chronic hepatitis (WMD 106.00, 95%CI 189.05 to 22.95). There may be a dose-effect relationship in Yinzhihuang injection, higher doses had better effect (WMD 11.50, 95%CI 16.53 to 6.47). No fatal side effects were reported.Conclusions It is noted that Yinzhihuang injection can abate jaundice of icteric viral hepatitis. Due to low statistical power and high risk of selection bias, performance bias and measurement bias of the included trials, these conclusions need to be treated cautiously.
The hallmark lesions of age-related macular degeneration (AMD) are drusen and basal linear deposit which are lipid substances deposited in Bruch membrane or the compartment on the Bruch membrane. There is a prevailing hypothesis that lipid and its oxidized derivant deposited in retina may have important roles in the pathogenesis of AMD. Lipid oxidation products are toxic, may affect the adjacent cells, induce inflammation, and trigger neovascularization.7-ketocholestoral (7KCh), a naturally occurring oxidized form of cholesterol, had been found to be toxic to retinal cells and able to induce chronic inflammation, which may play a critical role in the development of AMD. However the precise mechanism remains to be elucidated. Thus we will make a brief review of 7KCh and its association with AMD.
FLASH radiotherapy is a hotspot in the domain of tumor radiotherapy in recent years, which delivers at ultra-high dose rate (usually > 100 Gy/s) in an ultra-short time (1−50 ms) to the target volume. The FLASH effect will be generated after the organism is treated with FLASH radiotherapy, which makes the tumor more easy to be killed and the normal tissue is protected after radiotherapy. Because of the differences in sensitivity to FLASH radiotherapy between tumor tissues and normal tissues, FLASH radiotherapy has a subversive advantage in the treatment of tumors. In this paper, several studies since 1959 on the effects of ultra-high dose rate rays and FLASH radiation on cells and organisms are summarized. As the predecessor of FLASH radiotherapy, ultra-high dose rate radiotherapy has laid a very important foundation for the development of FLASH radiotherapy.
Choroidal nevus is one of the most common benign melanocytic tumor. The prevalence rate of choroidal nevi is 0.15% - 10.00%, which is high among whites and low among colored people, and is obvious higher in male than that in female. Secondary changes in the surrounding retina of the benign tumor, such as subretinal fluid and choroidal neovascularization, may result in vision loss. This benign tumor carries risks for transformation into malignant melanoma. The factors predictive of transformation into melanoma included greater thickness, subretinal fluid, visual symptoms, orange lipofuscin pigment, tumor location (tumor margin near optic disc), ultrasonography hollowness and absence of halo. Early identification of the related features which impair visual acuity is important for early treatment and better prognosis, and it is especially important to monitor the tendency of malignant transformation. Optical coherence tomography (OCT) could provide detailed information which aid in diagnosing, differentiating and monitoring of choroidal nevi. OCT and optical coherence tomography angiography are emerging as excellent techniques to investigate choroidal melanocytic lesions. The treatment modalities, such as laser photocoagulation, photodynamic therapy and intravitreal anti-vascular endothelium growth factor, have been proved to be effective for choroidal nevi with secondary changes. In the future, the relevant researches should be imposed to provide more detailed information in order to explore the nature and characteristics of this disease.
Atopic dermatitis (AD) is a chronic inflammatory skin disease characterized by severe itching and recurrent eczema-like lesions. With the increase in the global incidence of AD, the incidence of ocular complications in patients also increases. Retinal detachment (RD) seriously affects the vision of patients, and is more common in young and middle-aged people, often involving both eyes with poor prognosis. What’s more, there are many similarities between RD associated with AD and traumatic RD, such as peripheral retinal breaks, giant retinal tears and retinal dialysis. Regarding the mechanism of AD complicated with RD, the trauma theory is widely accepted. Scholars have also reported on the theory of anterior eye developmental abnormalities, inflammation-traction theory, and ectodermal origin theory. On AD complicated with RD, regardless of scleral buckling surgery or vitrectomy surgery, the rate of first retinal reattachment is low with severe proliferative vitreoretinopathy or chronic uveolar inflammation after surgery, which cause traction on the ciliary body and the retina separation appearance again or new cracks appearance. Combination of behavioral therapy, drug therapy and psychotherapy can effectively reduce the occurrence of RD; prevention of eye rubbing, reduction of traumatic exercise, rational use of glucocorticoids or immunosuppressants under the guidance of dermatologists are effective ways for AD patients to prevent RD occurrence. Regular eye examinations can help patients find RD as soon as possible so that they can be treated in time.