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.
ObjectiveTo investigate the expression of interleukin-18（IL-18）and signal transducers and activators of transcription 5（STAT5）in retina of 4-24-week-old diabetic rats, and explore the potential molecular mechanisms involved in diabetic retinopathy (DR).MethodsRetinal gene expression profile of healthy and 8-week-old diabetic rats was established with restriction fragment differential displaypolymerase chained reaction (RFDD-PCR), and the differences was analyzed by bioinformatics. IL-18 and STAT5 were filtrated as the candidate genes of DR. The expression of IL-18 and STAT5 in retina of diabetic rats with the age of 4, 8, and 24 weeks was observed by semi-quantitative reverse transcriptase-polymerase chain reaction（RT-PCR）.ResultsThe result of RFDD-PCR showed:expression of IL-18 was higher in healthy retina than that in diabetic one; expression of STAT5 was not found in healthy rats but in diabetic ones. The result of RT-PCR showed：compared with the normal, high expression of IL-18 was found in 4-week diabetic retina, reduced in 8-week one, and decreased to the lowest in 24-week one. The expression of STAT5 was not observed in healthy or 4week diabetic retina, but occurred in 8-week one, and increased in 24-week one. ConclusionThe expression of IL-18 and the activation of STAT5 may relate to the occurrance of DR. The expression of IL-18 doesn′t depend on the activation of STAT5. (Chin J Ocul Fundus Dis, 2005,21:258-260)
早产儿视网膜病变（ROP）是儿童盲的重要致盲原因之一，随着ROP防治指南的颁布以及ROP筛查工作的开展，我国ROP发病率和致盲率有所下降。正确认识和理解ROP分类、筛查标准和治疗指南；建立完善的ROP筛查体系，提高筛查水平；加强ROP临床和基础研究，将有助于进一步降低我国ROP发病率和致盲率
The prevalence of diabetes mellitus in adults of China has reached 12.8%. Diabetic retinopathy (DR) accounts for approximately 1/4-1/3 of the diabetic population. Several millions of people are estimated suffering the advanced stage of DR, including severe non-proliferative DR (NPDR), proliferative DR (PDR) and diabetic macular edema (DME), which seriously threat to the patients’ vision. On the basis of systematic prevention and control of diabetes and its complications, prevention of the moderate and high-risk NPDR from progressing to the advanced stage is the final efforts to avoid diabetic blindness. The implementation of the DR severity scale is helpful to assess the severity, risk factors for its progression, treatment efficacy and prognosis. In the eyes with vision-threatening DR, early application of biotherapy of anti-vascular endothelial growth factor can improve DR with regression of retinal neovascularization, but whether it is possible to induce capillary re-canalization in the non-perfusion area needs more investigation. Laser photocoagulation remains the mainstay treatment for non-center-involved DME and PDR.
Objective To explore the effect of oxygen inhalation on the retinae of newborn rats and its mechanism.Methods We mimicked the retinopathy of prematurity(ROP) by putting the newborn rats in high concentrated oxygen. One-day old rats were put into the oxygen box with the oxygen concentration of 80% for continuous 7 days; then in air condition for 7 days. The arterial blood oxygen pressure, retinal superoxide dismutase (SOD), and malondialdehyde (MDA) of the rats (1,2,4,7,8,9,11,14 days old) were examined. The diameter of retinal vessels′main branch and the coverage rate of peripheral vessels were measured in 7- and 14-day-old rats by ink perfusion. The retinal neovascularization of rats (8,9,11, 14 days old) were observed by HE staining. The rats of the same age fed in air condition were in the control group.Results The differential pressures of blood oxygen of rats (1,2,4,7 days old) in study group were significantly higher than those in the control group (P＜0.01), while the differential pressures of blood oxygen of rats (8,9,11,14 days old) in study group were lower than those in the control group (P＞0.05). The contents of SOD of the retinae in the rats ( 1,2,4,7,8 days old) were significantly lower than those in the control group(P＜0.01, P＜0.05 ), while the contents of MDA were significantly higher than those in the control group (P＜0.01,P＜0.05). The diameter of retinal vessels′main branch in 7-day rats was 75% of the control group, and the coverage rate of peripheral vessels was 22% of the control group; and was 61% and 73% respectively in 14-day-old rats. The neovascularization could be seen in 16.7% of the rats in the study group and nought in the control group.Conclusion The damage of free radical of the retina in high concentrated oxygen and hypoxia situation after oxygen supply may be one of the most important mechanism of ROP. (Chin J Ocul Fundus Dis，2003，19：269-332)
Purpose To clarify the relationship between diabetic retinopathy (DR) and maculopathy (DM) and explore the clinical implication of independent graduation of DM. Methods Fundus fluorescein angiography and routine ophthalmological examination were performed on 582 cases of diabetes.Their ocular fundi and macular impairments were graded. Results In general,the severity of diabetic macular impairment was accompanied by retinal involvement,but discrepancy existed between DM and DR.Degree I DM occurred in 5.4% (16/294) among cases without DR,in stage IV DR,degree Ⅲ DM accounted for the most part ,54.5% (116/213).There were still 5.1% (2/39) cases without DM in stage Ⅴ DR. Conclusion The degree of the macular lesions in DM is often not in parallel with the gradation of general affections in retinal tissue other than in macular region in DR,therefore,independentg radation of diabetic maculopathy has its clinical significance for choosing the optimal period of treating maculopathy and preserving the macular function. (Chin J Ocul Fundus Dis,2000,16:153-154)
ObjectiveTo investigate the clinical risk factors of preterm infants and its severity in premature infants with bronchopulmonary dysplasia (BPD) with retinopathy of prematurity (ROP).MethodsRetrospective clinical study was performed. A total of 126 preterm infants with BPD in the Neonatal Department of the Affiliated Hospital of Qingdao University from January 2016 to December 2018 were enrolled in the study. Among them, 69 were males and 57 were females, whose gestational age＜32 weeks and birth weight＜1500 g. BPD grades Ⅰ, Ⅱ, and Ⅲ were 63, 40, and 23 cases respectively. According to the presence or absence of ROP, children were divided into ROP group and non-ROP group, with 48 (38.1%) and 78 (61.9%) cases respectively. The differences of clinical data between the two groups were compared and analyzed. Quantitative data comparison between groups was performed by t test, and count data comparison was performed by χ2 test. The risk factors of ROP in BPD premature infants were analyzed by multi-factor logistics regression. The correlation between BPD severity and ROP severity was tested by Spearman rank correlation test.ResultsCompared with the non-ROP group, the ROP group had a smaller gestational age (t=5.988), lower birth weight (t=7.371), higher the application rate of oxygen concentration＞30% (duration of service＞24 h), high rate (χ2=17.244) and longer noninvasive ventilation time (t=－7.139), the differences were statistically significant (P＜0.05). In the logistic regression model, the noninvasive ventilation time was the risk factor for ROP in preterm infants with BPD (OR≈1.054, P＜0.05), while gestational age and birth weight were importantly protective factors for ROP in preterm infants with BPD (OR≈0.938, 0.996; P＜0.05). The results of the correlation analysis found that the severity of BPD was significantly positively correlated with the severity of ROP. As the severity of BPD increased, the severity of ROP increased, and the difference was statistically significant (rs=0.306, P＜0.035).ConclusionsFetal gestational age, low birth weight, hyperoxia, and long-term non-invasive mechanical ventilation are the main risk factors for ROP in preterm infants with BPD. The severity of BPD is positively correlated with the incidence and severity of ROP.
ObjectiveTo investigate relationship between ultrastructural changes and expression of basic fibroblast growth factor of diabetic retinopathy in rats.MethodsDiabetes was induced in rats with a single injection of streptozotocin (STZ) and divided into normal control group and 1- , 3- and 5- month diabetes group. The paraffin slide was observed by in-situ hybridization and immunohistochemistry, and retinal ultrastructure was examined by transmission electron microscopy.ResultsNo change of retinal ultrastructure was found in the control group. Different degrees of ultrastructure lesion were found in 1-month diabetic rats with fragmental increase of thickness of basement membrane, swelling of endothelial cells and obvions fingerlike processes in the capillary cavity, disconcentration of heterochromatin both in endothelium and pericyte, and swelling and degeneration of mitochondrion. The edema of endothelial cells of 3-month diabetic rats was more serious than that of 1month ones, and the capillary cavity was nearly occluded. In 5-month diabetic rats, the basement membrane was unevenly thickened, or obviously split. The positive rate of in-situ hybridization in 3-month diabetic rats was 77.8% while the positive rate of immunohistochemical stain was 55.6%, which increased to 88.9% in 5-month diabetic rats.ConclusionsThe occurrence of the ultrastructural changes in STZ rats with diabetic retinopathy is earlier than that of the expression of bFGF.(Chin J Ocul Fundus Dis, 2003,19:348-351)