[Photodynamic therapy with verteporfin combined with intravitreal injection of bevacizumab for occult and classic CNV in AMD]

Comparison of conbercept and ranibizumab for the treatment efficacy of diabetic macular edema: a Meta-analysis and systematic review

AIM

To evaluate the efficacy of intravitreal injection of conbercept (IVC) and ranibizumab (IVR) in patients with diabetic macular edema.

METHODS

Reviewers have searched 12 databases, including PubMed, Medline, EMBASE, Web of Science, Springer, ScienceDirect, OVID, Cochrane Library, ClinicalTrials.gov, cqVIP, WanFangdata and China National Knowledge Infrastructure (CNKI), up to December 28, 2018. RevMan 5.3 (Cochrane Library Software, Oxford, UK) was employed for statistical analysis. Fixed and random effects models were applied to assess heterogeneity. Odds ratio (OR) was applied for dichotomous variables; weighted mean difference (WMD) was applied for continuous variables. The confidence interval (CI) was set at 95%. Central macular thickness (CMT) and best-corrected visual acuity (BCVA) were employed to analyze the improvement of DME patients. Inclusion criteria for picking out studies were retrospective studies and randomized controlled trials (RCTs) that compared IVC and IVR for the treatment of diabetic macular edema.

RESULTS

Four retrospective studies and five RCTs were included with a total of 609 patients. No statistically significant difference was observed in mean CMT and mean BCVA in the baseline parameters [BCVA (WMD: -0.48; 95%CI: -1.06 to 0.10; P=0.1), CMT (WMD: -0.83; 95%CI: -15.15 to 13.49; P=0.91). No significant difference was found in the improvement of BCVA and adverse event (AE) in IVC group, compared with IVR group after treatment of loading dosage [the 1^st month BCVA (WMD: 0.01; 95%CI: -0.26 to 0.27; P=0.96), the 3^rd month BCVA (WMD: -0.04; 95%CI: -0.14 to 0.06; P=0.46); the 6^th month BCVA (WMD: -0.24; 95%CI: -1.62 to 1.14; P=0.73)], AE (OR: 0.84; 95%CI: 0.38 to 1.84; P=0.66)]. A slight difference was found in the effectiveness rate (OR: 1.70; 95%CI: 0.97 to 2.96; P=0.06), There were statistically significant differences between IVC and IVR treatment in terms of CMT [1^st month CMT (WMD: -19.88; 95%CI: -27.94 to -11.82; P<0.001), 3^rd month CMT (WMD: -23.31; 95%CI: -43.30 to -3.33; P=0.02), 6^th month CMT (WMD: -74.74; 95%CI: -106.22 to -43.26; P<0.001)].

CONCLUSION

Pooled evidence suggests that both IVC and IVR are effective in the therapy of diabetic macular edema and affirms that IVC presents superiority over IVR therapy in regard of CMT in patients with diabetic macular edema, but no statistically significant difference with regard to visual improvement. Relevant RCTs with longer-term follow-up are necessary to back up our conclusion.

Magnetic nanoparticles conjugated with "RPE cell -MCP-1 antibody -VEGF antibody" compounds for the targeted therapy of age-related macular degeneration: a hypothesis

Age-related macular degeneration (AMD) is the leading cause of vision loss in the elderly throughout the world. Treatment of AMD utilizing retinal pigment epithelium (RPE) transplantation represents a promising therapy. However, simplex RPE transplantation can only replace the diseased RPE cells, but has no abilities to stop the development of AMD. It has been indicated that oxidization triggers the development of AMD by inducing the dysfunction and degeneration of RPE cells, which results in the upregulation of local monocyte chemotactic protein-1 (MCP-1) expression. MCP-1 induces macrophage recruiment which triggers local inflammation. As a result, the expression of vascular endothelial growth factor (VEGF) is upregulated by MCP-1 mediated inflammation and results in the formation of choroidal neovascularization (CNV). We accordingly propose a targeted therapy of AMD by subretinal transplanting the compound of RPE cell, MCP-1 antibody, and VEGF antibody and using a magnetic system to guide RPE cell compounds conjugated with superparamagnetic iron oxide nanoparticles (SPIONs). Furthermore, SPION-labelled RPE cells can be tracked and detected in vivo by non-invasive magnetic resonance imaging (MRI). This novel RPE cell transplantation methodology seems very promising to provide a new therapeutic approach for the treatment of AMD.

Cellular localization of Visudyne as a function of time after local injection in an in vivo model of squamous cell carcinoma: an investigation into tumor cell death

OBJECTIVE

To evaluate the effects of time on cellular localization of Visudyne after local injection.

ANIMALS

Twenty athymic nude mice.

PROCEDURES

A squamous cell carcinoma (SCC) cell line (A-431) was injected into right and left dorsolumbar subcutaneous tissue of each mouse, representing treatment (T) and control (C) tumors. In experiment 1 (Exp 1; n = 10) and 2 (Exp 2; n = 10), the T tumors received a local injection of Visudyne (0.1 mg/cm(3)), and C tumors received an equal dose of 5% dextrose in water (D5W). Mice were randomly subdivided into two groups (A and B; n = 5 per group). Mice in Exp 1A and B were sacrificed 1 and 30 min after local injection, respectively. Experiment 1A and B tumors were evaluated by fluorescence microscopy to determine drug localization. Experiment 2A and B tumors were exposed to LED illumination 1 and 30 min after injection, respectively, and evaluated by transmission electron microscopy (TEM) to determine ultrastructural tumor cell damage.

RESULTS

Fluorescence was detected within the cytoplasm of T tumors in both Exp 1A and B. Significance was detected in fluorescence intensity between T1 min vs. T30 min (P = 0.03) and between T1 min and C1 min tumors (P = 0.01), respectively. Tumors in Exp 2A and B demonstrated evidence of apoptotic cell death.

CONCLUSIONS

Fluorescence microscopy demonstrated higher Visudyne concentration within SCC cytoplasm of 1 min compared with 30-min tumors. Transmission electron microscopy results revealed that tumors treated by photodynamic therapy (PDT) within 30 min of local injection undergo cellular apoptosis.