Mesenchymal stem cells (MSC) are considered to have important value in the treatment of various diseases because of their low immunogenicity, transferability, and strong tissue repair capacity. Stromal cell derived factor-1 (SDF-1) and its receptor CXC chemokine receptor 4 (CXCR4) pathway plays an important role in migration of MSC. The induction of homing of MSC to retina by regulating SDF-1/CXCR4 may exert the curative effect on diabetic retinopathy to greatest exent.
ObjectiveTo investigate the feasibility of electroencephalography (EEG) power spectrum analysis monitoring noninvasive intracranial pressure (ICP). MethodsBetween September 2008 and May 2009, the EEG signals were recorded in 62 patients (70 cases/times) with central nervous system (CNS). By using self-designed software, EEG power spectrum analysis was conducted and pressure index (PI) was calculated automatically. ICP was measured by lumbar puncture (LP). ResultsThe mean ICP was (239.74±116.25) mm H2O (70-500 mm H2O, 1 mm H2O=0.009 8 kPa), and 52.9% of patients had increased ICP. The mean PI was 0.29±0.20 (0.02-0.85). The Spearman rank test showed that there was a significant negative correlation between PI and ICP (rs=-0.849, P<0.01). The data from the patients with diffuse lesions of CNS and focal lesions were analyzed separately; the results showed there were significant negative correlations between PI and ICP in both groups (rs=-0.815, -0.912; P<0.01). ConclusionThe PI obtained from EEG analysis is correlated with ICP. Analysis of specific parameters from EEG power spectrum might reflect the ICP. Further research should be carried out.
Objective To observe the morphological changes of macular capillary in type 2 diabetic mellitus (DM) patients without clinical features of diabetic retinopathy (DR) by optical coherence tomography angiography (OCTA). Methods This is a prospective clinical case-control study. Forty-three eyes of 22 patients with DM without clinical features of DR (case group) and 40 control eyes of 20 age- and sex-matched healthy physical examination subjects (control group) were enrolled in this study. All subjects underwent OCTA examination with mode of retinal blood flow imaging, macular 3 mm×3 mm and 6 mm×6 mm area, signal strength ＞45. Foveal avascular zone (FAZ) area, foveal capillary density, parafovea capillary non-perfusion, and micro-aneurysm in shallow capillary vessel layer were evaluated. Results In case group, the mean FAZ area was (0.397±0.141) mm2 and the mean foveal capillary density was (44.6±0.62) %. In control group, the mean FAZ area was (0.253±0.112) mm2 and the mean foveal capillary density was (48.6±0.58) %. FAZ area of eyes in case group was larger than that in control group (t=1.017,P＜0.05). There was no difference of foveal capillary density between two groups (t=1.499,P＞0.05). The spider web-like FAZ and normal foveolar avascular zone were observed in eyes of control group. The parafovea capillary non-perfusion, abnormal foveolar avascular zone, micro-aneurysm and tortuosity of vessels were observed in eyes of case group. Parafovea capillary non-perfusion (χ2=4.542), micro-aneurysms (χ2=5.183) were seen more often in case group than control group (P＜0.05). Conclusion Type 2 DM patients have abnormal retinal vascular microcirculation before DR using OCTA, including larger FAZ area, parafovea capillary non-perfusion, abnormal foveolar avascular zone, micro-aneurysm and tortuosity of vessels.
ObjectiveTo observe the outcome of scleral buckle and vitrectomy for familial exudative vitreoretinopathy (FEVR) associated rhegmatogenous retinal detachment (RRD) with different stages. MethodsTwenty eyes in 19 patients were included in this study. All the eyes were staged according to the staging system of FEVR. There are 7 eyes at stage 3A, 4 eyes at stage 4A, 6 eyes at stage 4B, and 3 eyes at stage 5. According to classification of retinal detachment (RD) with proliferative vitreoretinopathy (PVR), PVR B was in 5 eyes, PVR C1 in 2 eyes, PVR C2 in 3 eyes, PVR C3 in 7 eyes, PVR D1 in 3eyes. Retinal holes responsible for the RD could be found in every case. Scleral buckle or vitrectomy were chosen according to FEVR staging, PVR classification, location of retinal breaks, extent of RD.Ten eyes (stage 3A in 7 eyes, stage 4A in 3 eyes;PVR B in 5 eyes, PVR C1 in 2 eyes, PVR C2 in 3 eyes) were undergone scleral buckle, the mean preoperative minimum resolution angle in logarithmic (logMAR) best corrected visual acuity (BCVA) is 0.60±0.32.Ten eyes (stage 4A in 1 eyes,stage 4B in 6 eyes,stage 5 in 3 eyes;PVR C2 in 1 eyes,PVR C3 in 6 eyes,PVR D1 in 3 eyes) were undergone vitrectomy, the mean preoperative logMAR BCVA is 1.81±0.53. The mean follow up was(20.20±7.25) months, range 3 to 30 months. Surgical outcome were estimated by the average number of operation, reattachment of retina and BCVA. ResultsFinal retinal attachment was obtained in 100% of all 20 eyes. The mean postoperative logMAR BCVA of scleral buckle group (0.34±0.32) is improved than preoperative BCVA, the difference wan statistically significant (t=2.932, P=0.017). The mean postoperative logMAR BCVA of vitrectomy group (1.42±0.64) is not changed compare with preoperative BCVA (t=1.812,P=0.103).The mean number of operation of scleral buckle group (1.10±0.32) is less than vitrectomy group's (2.20±0.42),the difference wan statistically significant (t=6.588, P=0.000). ConclusionsAmong the patients whose FEVR staging is less than 4A and PVR classification is less than C3,epiretinal membranes or subretinal membranes appears mild, and scleral buckle can achieve high success rate with less number of operations,and the BCVA is improved in most of the cases. For the patients whose FEVR staging is more than 4B and PVR classification is more than C3, proliferative vitreoretinopathy seems to be serious, retina can be effectively reattached via vitrectomy, however, the number of operations required is multiple, and the BCVA is probably unimproved after operation.
ObjectiveTo observe the effect of exosomes derived from human umbilical cord blood mesenchymal stem cells (hUCMSC) on the expression of vascular endothelial growth factor (VEGF) A in blue light injured human retinal pigment epithelial (RPE) cells. MethodshUCMSC were cultured with exo-free fetal bovine serum for 48 hours, and then the supernatants were collected to isolate and purify exosomes by gradient ultracentrifugation method. Transmission electron microscopy was used to identify the morphology of exosomes. Surface specific maker protein CD63 and CD90 were detected via Western blot. Cultured ARPE-19 cells were divided into normal control group, blue light injured group and hUCMSC exosomes treated group. Cells were exposed to the blue light at the intensity of (2000±500) Lux for 12 hours to establish the light injured models. The cells of hUCMSC exosomes treated group were treated by different concentrations of exosomes for 8, 16, 24 hours. The mRNA and protein of VEGF-A were determined by real time-polymerase chain reaction and Western blot. Immunofluorescence assay were used to detect the expression levels of VEGF-A. ResultshUCMSC exosomes were successfully isolated, they exhibited round or oval shape and their diameter ranged from 50 to 100 nm with membrane structure through electron microscope. hUCMSC exosomes expressed the common surface marker protein CD63 and the surface marker protein CD90 of hUCMSC. The protein and mRNA level of VEGF A in the blue light injured group increased significantly compared to that in normal control group (t=-16.553, -19.456; P < 0.05). After treating with low, middle and high concentration of hUCMSC exosomes for 8, 16 and 24 hours, the protein and mRNA level of VEGF A of injured RPE were significantly decreased (P < 0.05). With the treated time and concentration of hUCMSC exosomes improved, the protein and mRNA level of VEGF A of injured RPE gradually decreased (P < 0.05). Immunofluorescence assay showed the protein level of VEGF-A of injured RPE gradually decreased with the same concentration of hUCMSC exosomes treated over time. ConclusionhUCMSC exosomes can effectively down-regulate the mRNA and protein level of VEGF-A in blue light injured RPE, the effect depends on the concentration and treated time of hUCMSC exosomes.
ObjectiveTo observe the immunological regulation effects of human umbilical cord mesenchymal stem cells (hUCMSC) on glucose-damaged rhesus retinal vascular endothelial cells (RF/6A). MethodshUCMSC and RF/6A were co-culture according to 1:1 ratio in the co-culture system (Transwell plates), hUCMSC cells were added to upper chamber, while the lower chamber containing 25mmol/L glucose and RF/6A. There were three groups including RF/6A blank control group, high glucose treated RF/6A group, and high glucose treated RF/6A with hUCMSC co-culture group. MTT was used to measure the RF/6A cell viability. Western blot was used to to detect protein level of Foxp3. Enzyme-linked immunosorbent assay (ELISA) was used to detect the concentration of interleukin (IL)-17. ResultsMTT assay revealed that at the first day, the survival rate of the three groups had no significant difference (F=0.030, P > 0.05). On day 3 and day 7, the cell viability of the high glucose group was significantly lower than that of the control group (t=36.072, 27.890; P < 0.05), the cell viability of the high glucose treated RF/6A with hUCMSC co-culture group was higher than that of high glucose group (t=36.072, 19.650; P < 0.05).Western blot analysis showed that Foxp3 in high glucose RF/6A group was significantly lower than that in the control group at day 7 after culture (t=7.826, P < 0.05) and high glucose RF/6A with hUCMSC group (t=19.936, P < 0.05). ELISA showed that IL-17 in the high glucose group, high glucose with hUCMSC co-culture group was significantly higher than that of the control group (F=1 267.503, P < 0.05), while IL-17 in the hUCMSC co-culture group was significantly lower than that in high glucose group (t=17.386, P < 0.05). ConclusionhUCMSC can regulate the expression of Foxp3 and IL-17 to increase the proliferative ability of RF/6A, which was suppressed by high glucose.