Effectiveness of peripheral defocus spectacle lenses in myopia control: a Meta-analysis and systematic review.

AIM: To evaluate the effectiveness of peripheral defocus spectacle lenses (PDLs) in myopia control. METHODS: Literature retrieval on PubMed, Cochrane Library, Embase, and Web of Science databases, and the search time limit was from the establishment of each database to December 29, 2021 were conducted. Change of spherical equivalent refraction (SER) and axial change (AL) were extracted from the literatures that met the inclusion criteria, and RevMan5.3 software was used for Meta-analysis. RESULTS: A total of 4 randomized controlled trials (RCTs) were included in this Meta-analysis, involving 770 myopic children. The results showed that PDLs could delay the progression of myopia in children with myopia compared with single vision spectacle lenses (SVLs; WMD=0.21 D, 95%CI: 0.01, 0.41, P=0.04). However, there was no significant difference in controlling the growth of axial length (AL) in myopic children (WMD=-0.10 mm, 95%CI: -0.21, 0.01, P=0.07). The results of the effectiveness of myopia control between the two spectacle lenses showed that PDLs were more effective in controlling the progression of myopia (OR=5.73, 95%CI: 2.58, 12.70, P<0.001) and delaying the growth of AL (OR=44.25, 95%CI: 8.84, 221.58, P<0.001) than SVLs, and the differences were statistically significant. CONCLUSION: PDLs can control the progression of myopia compared with SVLs, but cannot delay the growth of AL, and the effectiveness of PDLs in myopia control better than SVLs.

Comparison of intravitreal aflibercept and dexamethasone implant in the treatment of macular edema associated with diabetic retinopathy or retinal vein occlusion: a Meta-analysis and systematic review.

AIM: To compare the efficacy and safety of intravitreal aflibercept with dexamethasone implant in the treatment of macular edema (ME) associated with diabetic retinopathy (DR) or retinal vein occlusion (RVO). METHODS: A comprehensive search of studies comparing dexamethasone and aflibercept in patients with ME was conducted at PubMed, Embase, and Cochrane Central Register of Controlled Trials from the beginning of library to April 16, 2021. Extracting the data including best-corrected visual acuity (BCVA), central retinal thickness (CRT), number of injections and serious adverse events (SAEs) from the final qualified articles. RevMan 5.3 software was used for Meta-analysis of the included studies. RESULTS: Totally 7 studies with 369 eyes were included. The causes of ME in the final screening study included RVO and DR. Compared with the aflibercept treatment group, the BCVA of the dexamethasone implant treatment group showed no significant difference in the follow-up for 3mo [mean difference (MD): -0.05, 95% confidence interval (CI): -0.11, 0.02; P=0.17] and 12mo (MD: -0.01, 95%CI: -0.38, 0.37; P=0.98), but it was slightly worse than the aflibercept group at 6mo (MD: 0.12, 95%CI: 0.03, 0.21; P=0.008). In terms of CRT reduction, there was no significant difference between the two groups at 3mo (MD: -28.14, 95%CI: -79.95, 23.67; P=0.29), 6mo (MD: 27.67, 95%CI: -84.89, 140.24; P=0.63), and 12mo (MD: -59.00, 95%CI: -127.37, 9.37; P=0.09). However, dexamethasone implant had fewer injections, but more adverse events such as elevated intraocular pressure (IOP) and cataract. CONCLUSION: Intravitreal injection of aflibercept and dexamethasone implant can both effectively increase BCVA and reduce CRT. Compared with aflibercept, dexamethasone implant is not inferior in improving vision and reducing CRT in the initial treatment period (3mo) and long-term treatment period (12mo). Besides, it has fewer injections and more likely to cause elevated IOP and cataract.

Activation of formyl peptide receptor-1 enhances restitution of human retinal pigment epithelial cell monolayer under electric fields.

PURPOSE: This study aimed at identifying the expression of functional formyl peptide receptor (FPR)-1 in human retinal pigment epithelium (hRPE) cells and to evaluate the role of FPR in regulation of wound closure of the hRPE monolayer under electric fields (EFs). METHODS: The expression of FPR in hRPE cells was analyzed with an immunofluoresence labeling assay and RT-PCR. Cultured wounded hRPE monolayers were exposed to EFs with free serum, 20%, serum, and a classical FPR agonist, N-formyl-Met-Leu-Phe (fMLF), respectively, for 3 hours. Cell monolayer migrations were traced using an image analyzer. Expressions of cell junction molecules were measured by RT-PCR, and the ultrastructure of cell junctions was observed with transmission electron microscopy (TEM). RESULTS: The expression of functional FPR was observed and localized along actin filaments in cellular lamellipodia and filopodia. EFs and fMLF significantly increased the migration rates of the wounded RPE monolayer. The migrating distances of monolayers were 24.262 ± 6.82 µm, 40.243 ± 5.069 µm, and 56.926 ± 7.821 µm in cells with free serum, 20% serum, and fMLF under EFs at 3 hours, respectively (P < 0.01). The mRNA expressions of connexin 43(Cx43) and zonula occludens (ZO)-1 were detected in hRPE cells. TEM revealed that cell junctions formed between hRPE cells in the monolayer. CONCLUSIONS: These results showed for the first time that functional FPR expresses in hRPE cells and that activation of FPR enhances migration of the wounded hRPE monolayer. The mRNA expressions and ultrastructures of cell junctions further demonstrated the RPE sheet as a monolayer migrating under EFs.

Inhibition of migration but stimulation of proliferation of human retinal pigment epithelial cells cultured with uniform vesicles of silicone oil.

BACKGROUND: It has been hypothesized that emulsification of silicone oil might stimulate preretinal membrane formation and proliferative vitreoretinopathy. This study aimed to test the effects of vesicles of silicone oil (VSO), which were prepared by a novel membrane emulsification technique, on the migration and proliferation of human retinal pigment epithelial (hRPE) cells in vitro. METHODS: VSO were produced by extrusion of the oil through a Supor membrane (Pall Life Sciences, Port Washington, NY, USA) with 0.45 microm pore size under a pressure of 0.1 MPa. hRPE cells were incubated with stained 25% VSO for 24 h to assess whether hRPE cells could phagocytize VSO. A wound-healing model was used by denuding cells from a glass slide to assess the migration of hRPE cells. The cells were then incubated with 25%, 50% and 100% VSO with or without serum for up to 72 h. The number of cells that had entered the denuded area was counted under a microscope. To assess the proliferative activity, the cells were incubated with 25%, 50% and 100% VSO, with or without serum, for 24 h. A total of 100 nuclei were examined for each slide, and the numbers of stained argyrophilic nucleolar organizer regions (AgNORs) in the nuclei were measured. RESULTS: The mean vesicle diameter of VSO prepared was 4.25 +/- 0.77 microm. The stained 25% VSO were phagocytized by hRPE cells. After the cells cultured with serum-free Dulbecco's Modified Eagle Medium (DMEM) were incubated with VSO, the numbers of migratory cells at higher concentrations (50% and 100%) of VSO were significantly decreased (48.9 +/- 5.37 and 10.6 +/- 3.03 respectively) compared to controls (69.9 +/- 9.88; P < 0.01). After the cells cultured with serum-free DMEM were incubated with VSO, the number of AgNORs in nucleus at 100% VSO was significantly increased compared to controls (3.1 +/- 0.72 vs 1.6 +/- 0.6; P < 0.01). CONCLUSION: The result indicated that VSO inhibited the migration but stimulated the proliferation of hRPE cells.

[A simple strategy for the rapid selection of effective antisense fragments targeting human genes].

Antisense RNAs have often been used to study functions of human genes. In order to obtain the effective antisense fragments, researchers always have to face repeated works including cell culture and transfection etc. Here we chose yeast, Saccharomyces cerevisiae, as a model organism to explore the simple and effective way to obtain antisense fragments targeting human genes. This single-cell eucaryote divides rapidly, can be cultured easily just as E. coli, and possesses many biological processes similar to mammalian. Thus, it is the best choice for the study focus on human gene transcription and other biological processes. Human Elongator complex was found to be very similar to the yeast Elongator both in composition and its interaction with RNA polymerase II. The elp3 subunit of human Elongator can significantly complement the growth defects of Yeast elp3 Delta Strain. So we used yeast complementation systems to select the antisense fragment targeting help3. Three different fragments including full length (a1 644), HAT-deletion (a1 107) and HAT(a450) sequence of help3 were amplified and inserted into pRS313 or pRS314 to construct antisense plasmids pRS313a1 644, pRS314a1 107 and pRS314a450. Through the sensitive assay and RT-PCR detection of help3 and ssa3 expression in yeast, we approved that the HAT-deletion fragment (a1 107) repressed the expression of cotransformed help3 significantly and reduced the complementation ability of help3 dramatically in yeast. Then the a1 107 antisense mammalian expressing plasmid was constructed and transfected into Hela cells. Northern blot assay indicated that a1 107 significantly reduced the expression of help3 in HeLa cells. So we regard that cotransforming targeting human gene and its antisense fragments into yeast and obtaining the significant reduction expression of targeting human gene is a simple strategy for the selection of antisense fragment targeting human genes.

[Cytoskeleton changes of cultured human retinal pigment epithelial cells in a mechanical stress model].

OBJECTIVE: To observe changes of the cytoskeleton of cultured human retinal pigment epithelium (hRPE) cells in a mechanical stress model in vitro. METHODS: Ferric oxide beads, coated with collagen, were added to dishes containing substrate-attached hRPE cells. After incubation, the cells were washed to remove unbound beads. The cells were pretreated by actin polymerization inhibitor cytochalasin D (0.05 mmol/L, 25 min). Before and 4, 8, 12 and 24 h after vertical magnetic force application the cells were stained for actin and vimentin using immunity fluorescence double labelled technique and analyzed with confocal microscopy. RESULTS: Four hours after force application, the polarity of hRPE cells was changed, and actin was polymerized into filaments in array of them along with the direction of the force. Cytoskeleton filaments were located mainly around the nucleus and the ferric oxide beads. Pretreatment with cytochalasin D, the same changes as described above occurred 8 h after magnetic force application. CONCLUSIONS: Mechanical force could induce changes of distribution of cytoskeleton in hRPE cells, which are some biological characteristics of muscle cells, and this may facilitate the cellular migration and proliferation.

[Effects of mechanical stress on expressions of monocyte chemoattractant protein-1 and interleukin-8 of cultured human retinal pigment epithelial cells].

OBJECTIVE: To investigate the expressions of monocyte chemoattractant protein-1 (MCP-1) and interleukin-8 (IL-8) of cultured human retinal pigment epithelial (hRPE) cells under mechanical stress in vitro, so as to mimic and understand the role of these 2 inflammatory cytokines in the early stage of development of primary retinal detachment. METHODS: Ferric oxide beads coated with collagen were added to the culture plate containing wall-attaching hRPE cells and then the cells were incubated and washed to remove the unbound beads. A magnet was put to the culture plate to provide vertical magnetic force. Cytochalasin D (CD) was added to the culture fluid to inhibit the phagocytizing, secreting, and moving functions of the hRPE. Before the experiment and 15 min, 0.5 h, 1 h, 4 h, and 8 h the beginning of experiment, the MCP-1 mRNA and IL-8 mRNA in the hRPE cells were measured with reverse transcriptase polymerse chain reaction (RT-PCR), and the MCP-1 and IL-8 protein expression in the supernatants was tested with enzyme-linked immunosorbent assay (ELISA) kits. RESULTS: MCP-1 and IL-8 mRNA were expressed at very low levels in the RPE cells and supernatant not exposed to magnetic force. After exposure to magnetic force, both MCP-1 and IL-8 mRNA demonstrated "double peaks" expression. Their first peak levels appeared within 0.5 h, being 3.30 ng/L +/- 0.12 ng/L and 1.88 ng/L +/- 0.08 ng/L respectively. The first peaks of MCP-1 and IL-8 protein expression were within 1 h, being 552.05 ng/L +/- 7.64 ng/Land 236.67 ng/L +/- 14.30 ng/L respectively, and the second peaks appeared about 4 hours later. After cytochalasin D pretreated, the expression and secretion of both MCP-1 and IL-8 of the hRPE cells were significantly decreased to the levels of 2.36 ng/L +/- 0.27 ng/L and 1.64 ng/L +/- 0.08 ng/L, and 353.80 ng/L +/- 16.68 ng/L and 101.86 ng/L +/- 15.92 ng/L respectively. CONCLUSION: Mechanical stress induces the RPE cells to express MCP-1 and IL-8, and this effect was inhibited in part by pretreatment of CD, indicating that the cytoskeleton may be involved in the effect and that these two inflammatory cytokines take a part in the early stage of development of primary retinal detachment.

[Expression of adrenomedullin and adrenomedullin receptor in the epiretinal membranes of proliferative vitreoretinopathy].

OBJECTIVE: To investigate the expression of adrenomedullin (ADM) and ADM receptor (ADMR) in epiretinal membranes (ERM) of proliferative vitreoretinopathy (PVR). METHODS: The expression of ADM and ADMR in 10 ERM were studied by in situ hybridization analysis (ISH). RESULTS: ADM and ADMR mRNAs were expressed in 7 of 10 specimens. The positive signals were distributed unevenly in positive cells. Some cells expressed mainly in the cytoplasm and the others expressed mainly in the nucleus. CONCLUSION: ADM and ADMR are expressed in the ERM of PVR, indicating that ADM and ADMR may play a role in the pathogenesis of PVR.