ObjectiveTo analyze the regulative rule of mRNA of vascular endothelial growth factor (VEGF) in mice with oxygen-induced retinopathy, and to elucidate the possible mechanism of occurrence of neovascularization in retinopathy of prematurity (ROP).MethodsSixty 7-day-old C57BL/6J mice were divided into oxygen-induced retinopathy group and control group. In oxygen-induced retinopathy group, 36 mice were exposed to 75% oxygen for 5 days and then to room air for 5 days; in control group, 24 mice were raised in room air. Vascular perfusion of fluorescein and retinal stretched preparation were used to observe the morphologic changes of retinal vessels. Reversal transcriptionpolymerase chain reaction (RT-PCR) was used to observe changes of VEGF mRNA in each group. ResultsIn oxygen-induced retinopathy group, the morphologic characteristics of retinal vessels were the unperfused area at the center of superficial and deepseated vessels, and the neovascularization appeared at mid-peripheral retina after 2 days in relative hypoxia condition. The results of RT-PCR showed space-time corresponding relation between expression of VEGF and neovascularization, which meant that the transcription of VEGF mRNA decreased in hyperxia conditionand increased in relative hypoxia condition. ConclusionHypoxia is the main reason of occurrence of retinal neovascularization; increased expression of VEGF caused by relative hypoxia after hyperxia might be effective in reducing the occurrence of neovascularization in ROP.(Chin J Ocul Fundus Dis, 2005,21:292-295)
Objective To determine the association between the geneti c polymorp hisms of vascular endothelial growth factor (VEGF) gene and the prognosis for retinopathy of prematurity (ROP) in Chinese. Methods Twenty infants with threshold ROP who had undergone retinal photocoagulation were in the treated group and 20 infants with self-regressed ROP without any treatment were in the control grou p . In the two groups, all the infants had oxygen-breathing history and the sex a n d gestational age were all suitable to be compared, except birth weight. Polymer ase chains reaction-restriction fragment length polymorphism was used to determine the frequencies of VEGF genes in the two groups. Results The frequencies of +405C allele were higher in the treated group than those in the control group (P＜0.05). The frequencies of the VEGF-460T/C and +936C/T ploymorphisms were similar in both groups (P＞0.05). Conclusions The +4 05C/G ge netic polymorphisms of VEGF may correlate to the prognosis of ROP. The carriers of +405CC allele are more susceptible to ROP.
ObjectiveTo explore the risk factors of diabetic retinopathy.
MethodsWe retrospectively analyzed the clinical data of 137 patients with diabetes mellitus (DM) from July 2012 to July 2015. According to the situation of retinopathy, the patients were divided into three groups. Forty-three patients without retinopathy were regarded as the control group, 46 non-proliferative retinopathy patients as the observation group, and 48 patients with proliferative retinopathy as the trial group. DM blood pressure, blood glucose, glycosylated hemoglobin, blood lipid, albumin creatinine ratio and other indicators were collected and analyzed, and multiple-factor non-conditional logistic regression analysis was carried out.
ResultsGlycosylated hemoglobin, total cholesterol, triglyceride, low density lipoproteincholesterol, high density lipoprotein cholesterol, body mass index, postprandial 2-hour blood glucose and fasting blood glucose were not significantly different among the three groups (P ＞ 0.05) , but the duration of diabetes, vascular endothelial growth factor and urinary albumin creatinine ratio were significantly different (P ＜ 0.05) . The diabetic duration, glycosylated hemoglobin, systolic blood pressure, urinary albumin creatinine ratio and vascular endothelial growth factor were independently associated with diabetic retinopathy (P ＜ 0.05) .
ConclusionThe prolonged disease course of diabetic patients, unstable status of blood glucose and blood pressure, and the increase of blood vessel growth factor and vascular endothelial growth factor can cause the development of diabetic retinopathy.
Objective To investigate the degree of retinal development in preterm infants.MethodsFlash electroretinography (ERG) was performed on 25 healthy preterm infants and 25 full-term ones, and the response of rod cells and cone cells and maximal mixed responses were recorded. The delitescence and amplitudes of a-and b-waves and the ratio of amplitudes of b-/a-wave of maximal responses were analyzed. ResultsCompared with the full-term infants, The delitescence of responses of rod cells in preterm infants was statistically longer（t=11.007，P=0.000）but without any significant changes of amplitudes （t=1.836，P=0.069）; statistically longer delitescence (t=2.44, P=0.010; t=10.800, P=0.000) and lower amplitude (t=5804，P=0.000; t=5.809,P=0.000) of a-and b-wave of maximal response were found in preterm infants group. In the response of cone cells, there were significant differences of the delitescence （t=4.444，P=0.000）and amplitude （t=3.819，P=0.000）of a-wave and delitescence of b-wave（t=2.850，P=0.005） between the two groups, and no statistical difference of amplitude of b-wave （t=0.486，P=0.628） between the two groups. The ratio of amplitudes of b-/a-wave of the maximal mixed response was not significantly different between the two groups （t=1.142，P=0.256）.ConclusionsThe development of retinal function is slower in preterm infants than that in full-term ones.(Chin J Ocul Fundus Dis, 2005,21:285-287)
Objective To investigate the incidence of retinopathy of prematuri ty (ROP) in the area of Shanghai, and to provide the preliminary data for the ev aluation of present criteria for ROP screening. Methods Record s of 289 prematur e infants who had undergone ROP screening from the four NICU in Shanghai between February 2004 and January 2005 were analyzed. Screening criteria included prete rm infants or low birth weight (LBW) infants with BW of 2000g or less. The first examination starts at 4 to 6 weeks chronologic age or 32 weeks post conceptual age. Results In the 289 screened infants, 19 had developed acu te ROP. There we re 3 threshold ROP, 7 prethreshold ROP and 9 developed ROP less than prethreshol d. The incidence of ROP was 6.6%. According to the British recommended guideline s（BWle;1500 g or GAle;31 weeks）, only 119 out of 289 needed screening and one ca se of stage 1 ROP was missed; the incidence of ROP was 15.1% (18/119). When lowered sc reening criteria to the American guidelines（BWle;1500g or GAle;28 weeks）, t here were only 83 infants needed screening, and we missed 2 stage 1 and 1 prethreshold ROP and the incidence of ROP was 19.3% (16/83). Conclusions The i ncidence of ROP i s 6.6% according to our study. It is lower than other reports and it has somethi ng to do with our present screening guideline. Further epidemiological data are needed to modify the guideline accordingly.
ObjectiveTo detect the development of retinal neovascularization (NV) induced by metabolic acidosis in neonatal rats and investigate the relationship between the occurrence of NV and vascular endothelial growth factor (VEGF).
MethodsA total of 425 newborn Sprague-Dawley rats in experimental group underwent tubal feeding of NH4Cl (535 mg/kg) with the concentration of (50 mg/ml) (twice per day) from the 2nd day after the birth for 6 days and followed by a period of recovery. Additional 150 neonatal rats were in the control group without the tubal feeding. The rats were executed at the 3rd, 5th, 8th, 10th, 13th, 20th day after birth respectively. The retinal vessels were evaluated through retinal stretched preparation andadenosine diphosphatase (ADPase) staining; VEGF in retina was detected by enzymelinked immunosorbent assay(ELISA).ResultsIn the experimental group, the incidence of retinal NV at the 3rd, 5th, 8th, 10th, 13th, 20th day after birth was 0%，9%，26%，55%，19%, and 0% respectively. At the 3rd day, the expression of VEGF protein was lower in experimental group ［（101.1±14.2 ）pg/mg］ than that in the control group ［（133.2±15.9） pg/mg］（P＝0.004）, while at the 8th day it was higher in experimental group［(98.4±19.2) pg/mg］than that in the control group［（78.1±8.7） pg/mg］（P=0.028). There was no significant difference between the two groups at the 5th, 10th, 13th, and 20th day (Pgt;0.05). ConclusionsMetabolic acidosis may induce NV by injuring the developing retinal vessels. Retinal NV induced by acidosis relates to VEGF. (Chin J Ocul Fundus Dis, 2005,21:296-299)
ObjectiveTo compare the therapeutic effects of 577 nm laser panretinal photocoagulation (PRP) between one time multi-point scanning mode and multiple time single-point mode in the treatment of eyes with non-proliferative diabetic retinopathy (NPDR).
MethodsThis is a prospective controlled study from August 2013 to February 2014. A total of 29 patients (46 eyes) with clinically diagnosed severe NPDR were randomly divided into two groups including the treatment group (12 patients, 22 eyes) and the control group (17 patients, 224 eyes). The treatment group received one time PRP of multi-point scanning mode, and the control group received 3-4 times of PRP with single-point mode. In order to evaluate its efficacy, the best corrected visual acuity was measured before treatment, and 1 day, 1, 2, 6 and 12 months after treatment. The average threshold sensitivity, a/b-wave amplitude of flash ERG (F-ERG) in the 30°-60° visual field, and fundus fluorescein angiography (FFA) of the change were also compared between the 2 groups. The laser energy and the number of laser spots were compared, and the laser energy density was calculated.
ResultsThe response rate was 86.4% and 79.2%, respectively in the treatment and control group, the difference was not statistically significant (χ2=0.414, P > 0.05). Compare to the pre-treatment measurement, the average threshold sensitivity, a/b-wave amplitude of F-ERG in the 30°-60° visual field were reduced at 1 day after treatment both in treatment and control group, the differences were statistically significant (P < 0.05). The average threshold sensitivity, a/b-wave amplitude of F-ERG were no difference between treatment and control group at 2m, 6m and 12m after treatment (P > 0.05). The average laser power, number of laser spots and energy density were (537.50±64.69) mW and (339.09±132.09) mW, (1934.32±426.38) points and (2061.42±375.49) points, (0.35±0.12) mW o ms/μm2 and (1.95±0.86) mW·ms/μm2 in the treatment group and the control group, respectively. The average laser power and energy density was statistically different between the 2 groups (P < 0.05), while the number of laser spots was no difference (P > 0.05).
Conclusions577 nm multi-point scanning laser can complete the PRP at one time, and achieve the same therapeutic outcomes with the single-point mode which need several times to complete the PRP in the eyes with severe NPDR, and have lower energy density, and thus relative minor function damage.
Intravitreal injection of anti-VEGF drugs for the treatment of retinopathy of prematurity (ROP) is a hot topic of research, and it can be used to treat the ROP (Ⅰzone). The current anti-VEGF drugs include bevacizumab, ranibizumab, aflibercept and conbercept, etc. However, in recent years, several studies have confirmed that anti-VEGF drugs have an increased recurrence rate and a longer recurrence time than conventional laser photocoagulation therapy. The follow-up period should be extended and repeated injections may be required. Due to the lack of large-scale prospective clinical studies, the recurrence rate, time window of recurrence, risk factors and treatment methods of various anti-VEGF drugs for ROP are still unclear. Anti-VEGF drugs in the treatment of ROP needs to accumulate more evidence-based medical evidence.
ObjectiveTo evaluate the efficacy and safety of intravitreal ranibizumab (IVR) for the treatment of retinopathy of prematurity(ROP).
MethodsA total of 57 eyes of 29 premature infants with diagnosis of high-risk pre-threshold, threshold ROP, or aggressive posterior ROP were reviewed and analyzed in the study. The lesions of 18 eyes were located in zoneⅠ, 39 eyes were located in zoneⅡ. All infants in the study received IVR (10 mg/ml, 0.025 ml) as the initial treatment within 24 hours after diagnosis. Follow-up examinations were performed after treatment, every week at the first month, every 2 weeks at the second and third month, every month afterward, until vascularization of zoneⅢwas observed. Follow-up ranged from 16 weeks to 52 weeks, and the average follow-up time was (28.1±11.7) weeks. If the infants didn't respond positively to the treatment or the disease recurred, the additional treatments were applied. 36 eyes (63.2%) received a single injection, whereas 21 eyes (36.8%) received additional treatments. The follow-up examinations included the development of retinal vessels, the ocular or systemic adverse events.
ResultsAmong the eyes, the development of peripheral retinal vessels could be observed in 36 eyes (63.2%) which received a single injection; clinical improvement in 11 eye (19.3%) which received repeat injection; stable disease in 10 eyes (17.5%) which received laser therapy. Among the eyes, 18 eyes (31.6%) recurred, including ggressive posterior ROP (14 eyes), threshold ROP (2 eyes) and high-risk pre-threshold ROP (2 eyes). The mean time of recurrence was (5.7±2.1) weeks (range 2.0-8.0 weeks). Three eyes (5.3%) of high-risk pre-threshold, threshold ROP lacked a positive response to the treatment. The lesions were controlled after additional laser given in these eyes. No serious ocular or systemic adverse events associated with the drug or the injection was observed during the follow-up period.
ConclusionIVR is safe and effective for most ROP infants. In cases of recurrence or no response, conventional laser treatment or an additional IVR injection were needed.
ObjectiveTo observe the expression of CD147, matrix metalloproteinases-2 (MMP-2) and vascular endothelial growth factor (VEGF) in a rat model of oxygen induced retinopathy (OIR).
MethodsEighty-four neonatal Wistar rats were divided into two groups randomly, the hyperoxia group (n=42) and the control group (n=42). Oxygen induced retinopathy was established in the hyperoxia group, the control group was raised in room air. Wholemonts were prepared from postnatal day (p) 7 and 14 rat retina to observe retinal vascular morphology. The number of endothelial cells to break through the internal limiting membrane was counted from p14 retinal paraffin sections. Expression of CD147, MMP-2 and VEGF protein levels was analyzed by immunohistochemistry on p12, p14, and p16 retinal sections. At the meantime, correlation between CD147 and MMP-2, VEGF was analyzed by two-way analysis of variance (ANOVA) test.
ResultsAt p7, the retinal vasculature of the control group was radial distributed with large caliber. In OIR group, there were vasoconstriction, large area of avascular zone and a few small areas of vascular network. At p14, the normal untreated rat had interwoven retinal vasculature, but in OIR group, the retinal vasculature was expanded and tortuous, and forming lots of neovascular cluster in the boundary of the perfusion and non-perfusion regions resulting exudation and hemorrhage. At p14, the endothelial cell nuclei breakthrough the internal limiting membrane was (1.30±1.26) and (19.70±3.56) respectively in control and OIR group, the difference was statistically significant (t=21.813, P<0.01). Immunohistochemical staining showed that CD147, MMP-2, VEGF expression was low in control group but high in OIR group. From p12 to p16, CD147, MMP-2 and VEGF protein expression increased in OIR retinas compared with control samples(p12:t=5.612, 4.122, 4.955; P<0.01. p14:t=11.390, 8.047, 12.176; P<0.01. p16:t=6.355, 4.422, 5.110; P<0.01).
ConclusionCD147, MMP-2 and VEGF were highly expressed in the rat model of oxygen induced retinopathy.
