ObjectiveTo observe the influence of human umbilical cord mesenchymal stem cells (hUCMSC) transplantation into vitreous cavity of diabetic rats on the retinal morphology, and the expression of glial fibrillary acidic protein (GFAP) and rhodopsin (RHO). Methods78 male Sprague-Dawley rats were used. 70 rats were injected with streptozotocin by tail vein injection at a dose of 40 mg/kg to establish the diabetes mellitus model, and another 8 rats were injected with 0.1 mol/L pH 4.0 citric acid buffer at the same dose as the normal control group. After 6 weeks of modeling, 10 rats were taken as the control group of diabetic model. hUCMSC suspension was injected into the right eye vitreous cavity of the remaining 60 rats, and the same volume of Dulbecco's modified Eagle/F12 medium was injected into the left vitreous cavity as control eyes. 1, 2 and 4 weeks after transplantation, follow-up experiments were performed. The experimental eyes were labeled as U1, U2, and U4 groups, while the control eyes were recorded as D1, D2, D4, and each group consisted of 20 eyes. After paraffin section and hematoxylin-eosin staining, the structure of the retina was observed by optical microscopy and the thickness of the outer nuclear layer and the inner nuclear layer (INL) were measured. The distribution and migration of hUCMSC in rat retina were observed by frozen section-tissue immunofluorescence assay. The mRNA and protein expression of GFAP and RHO in the retina were detected by real-time quantitative polymerase chain reaction (PCR) and Western blot assays. ResultsThe results of optical microscope observation showed the normal structure of retina in normal control group. The retinal nerve fiber layer (NFL) was thinned and the number of retinal ganglion cells (RGC) in the control group of diabetic rats was decreased. The decreased number and disorder arrangement of RGC were observed as well in U1, D1 rats. The RGC number of U2, U4, D2, D4 rats was gradually decreased. Compared with D4 group, the thickness of INL in U4 group was significantly increased (P < 0.05). Tissue immunofluorescence assay showed that hUCMSC were distributed along the inner limiting membrane in the retina of the U1 group, while the number of hUCMSC in the U2 group was gradually decreased, mainly in the NFL and ganglion cell layers. Real-time PCR and Western blot data indicated that the relative expression of GFAP mRNA and protein in the diabetic retina was significantly increased, and the relative expression of RHO mRNA and protein decreased gradually in the diabetic model group and the D1, D2, D4 groups. Compared with D2 and D4 groups, the mRNA and protein expression of GFAP in U2 and U4 groups were decreased, and the relative expression of RHO mRNA and protein were all increased (P < 0.01). ConclusionhUCMSC could migrate and integrate into the retina, after the transplantation into the vitreous cavity of diabetic rats, which reduced the expression of GFAP, but enhanced the expression of RHO.
Objective To observe the survival of human umbilical cord derived mesenchymal stem cells (hUC-MSCs) after injection into the vitreous of rabbits,and the animal safety under those procedures.Methods Twentyseven pigmented rabbits were randomly divided into 3 groups (intravitreal injection 1 week group，2 weeks group and 4 weeks group)， each with 9 rabbits.For each animal the right eye was the experimental eye receiving hUCMSCs injection,while the left eye was the control eye receiving culture medium. The rabbit eyes were examined by slitlamp microscope, indirect ophthalmoscopy, fundus photography, fundus fluorescence angiography（FFA）and Tonopen tonometer before and after injection. hUCMSCs were labeled by CMDil in vitro, and their survival status was measured by confocal fluorescence microscopy, light microscope and transmission electron microscope at 4 weeks after injection. Results Four weeks after injection, a large number of the hUCMSCs were still alive in the vitreous cavity. The overall condition of those rabbits was good. The anterior segment and retina of experimental eyes were normal, without hyperfluorescence, hypofluorescence and leakage in the retina at 1,2 and 4 weeks after injection. There was no significant difference on IOP before and after injection at different time points (P＞0.05), and no obvious changes at cornea, anterior chamber angle,lens,retinal structure by.light microscope and transmission electron microscope examination.Conclusion hUC-MSCs can survive in the rabbit vitreous for four weeks；intravitreal injection of hUCMSCs was safe and feasible.
Objective Toinvestigate the influence of photocoagulation on macular function and morphous in patients with diabetic retinopathy (DR).Methods Forty eyes of thirty patients with severe nonproliferative diabetic retinopathy (NPDR) were examined by multifocal electroretinogram (mfERG) and optical coherence tomography (OCT) before and 2,7, and 14 days after photocoagulation. The results were statistically analyzed by using analysis of variance and t test; the changes of macular function and macular fovea thickness were detected and observed.Results P1 response densities of ring 1,3,and 5 were 131.79plusmn;50.92，37.50plusmn;17.27，24.07plusmn;11.49，respectively,2 days after photocoagulation; and were 212.96plusmn;53.75，46.70plusmn;15.89，and 30.91plusmn;10.78, respectively, before photocoagulation. The densities before and after photocoagulation differed much（t=7.910, 2.174, 2.205; Plt;0.05）. N1 response density of ring 4 was（60.39plusmn;20.69） and the prephotocoagulation corresponding response density was （107.11plusmn;44.63）; the difference was significant（t=5.375，Plt;0.01）. The latency of P1 of ring 4 was（41.83plusmn;3.41），which had significant statistically difference（t=-2.770，Plt;0.05) with that before photocoagulation（39.52plusmn;2.64); there was no significant changes in the latency of N1 (Pgt;0.05). The most significant changes of P1 and N1 response densities occurred in the central macular 5deg; area. Seven days after photocoagulation, the response density of P1 and N1 in the central macular 5deg; area seemed to be recoverd to some extend and increased to （179.70plusmn;47.10）and (81.11plusmn;34.18) respectively until 14 days after photocoagulation, which was still much lower than that before the photocoagulation（t=3.840, 2.746; P＜0.05）; the response densities of other areas had no significant differences (P＞0.05). Seven days after photocoagulation,the latency of P1 in ring 4 was delayed to（41.78plusmn;3.57）, which had significant difference（t=-3.144，P＜0.01）with that before the photocoagulation（39.52plusmn;2.64) ; but there was no significant difference between 14 days after photocoagulation and prephotocoagulation (t=-1.809，P＞0.05). The latency of N1 in ring 1 was（20.67plusmn;3.85）at seven days after photocoagulation, It had no significant difference (t=-1.171,P＞0.05) with that before the phtocoaguation（18.78plusmn;3.29）. Before and 2 days after photocoagulation, the macular fovea thickness were（224.42plusmn;122.88）and（274.85plusmn;108.20）respectively, and the difference was statistically significant（t=-2.420，P＜0.05）. Forteen days after photocoagulation，the macular fovea thickness was（236.29plusmn;70.45），It had no significant difference with that before the photocoagulation（t=-0.578，P＞0.05）. Before and seven days after photocoagulation, P1 response density had obvious negative correlation with corresponding macular fovea thickness（r=-0.755，Plt;0.01; r=-0.594，Plt;0.05）. Conclusions After photocoagulation in patients with DR，the macular function decreased in a certain degree，and the relationship of macular retinal function and macular morphology changes was close; combination of mfERG and OCT can evaluate macular function and macular morphology structure comprehensively and objectively.
ObjectiveTo evaluate the safety and efficacy of 27G micro-incision vitrectomy surgery (MIVS) combined with intravitreal injection of ranibizumab (IVR) in the treatment of retinopathy of prematurity (ROP) with early intervention failure.MethodsRetrospective case series was performed. Fourteen eyes (11 infants) with ROP who underwent 27G MIVS combined with IVR were included from March 2016 to January 2018 in Shenzhen Eye Hospital. Among them, there were 5 males with 7 eyes, 6 females with 7 eyes. The average gestational age of the infants was 28.12±0.90 weeks; the average birth weight was 1 023.64±200.96 g. Before the early clinical intervention, 1 infant (2 eyes) had ROP in zone Ⅰstage 3 with plus disease, 8 infants (10 eyes) had ROP in zone Ⅱ stage 3 with plus disease, and 2 infants had ROP in aggressive posterior ROP. Six eyes underwent laser photocoagulation, while 8 eyes received laser therapy combined with IVR. Six eyes of stage 4A ROP and 8 eyes in stage 4B. Retinal detachment was detected with a mean of 10.44±9.21 weeks. At the time of surgery, the average post-conceptional age was 48.02±8.09 weeks. All the affected eyes were treated with standard sclera with three incisions 27G MIVS. During the operation, only local vitrectomy was performed to release and clear fibroascular proliferation in the optic disc, anterior macular area and pericristal area. After surgery, 10 mg/ml of ranibizumab 0.03 ml was injected into the vitreous cavity. The average follow-up time was 23.36±8.34 months. The primary objectives were the condition of retinal reset, ROP progression control and complications.ResultsAll patients had uneventful surgeries with an average duration of 32.86±9.35 mins. Of the 14 eyes, 12 eyes (85.71%) were controlled, 8 eyes (57.14%) had a good rearrangement of macular structure, while 4 eyes with macular traction. Two eyes had ROP progression, recurrence of retinal detachment, posterior synechia. Complicated cataract was in 1 eye. Proliferative vitreoretinopathy and retinal detachment was in 1 eye after 7 months the operation.Conclusion27G MIVS combined with IVR is a safe and effective treatment for ROP with early clinical intervention failure.