RESUMEN
This work reports the fabrication of iron oxide mesoporous magnetic nanostructures (IO-MMNs) via the nano-replication method using acid-prepared mesoporous spheres (APMS) as the rigid silica host and iron (III) nitrate as the iron precursor. The obtained nanosized mesostructures were fully characterized by SEM, TEM, DLS, FTIR, XRD, VSM, and nitrogen physisorption. IO-MMNs exhibited relatively high surface areas and large pore volumes (SBET = 70-120 m2/g and Vpore = 0.25-0.45 cm3/g), small sizes (~300 nm), good crystallinity and magnetization, and excellent biocompatibility. With their intrinsic porosities, high drug loading efficiencies (up to 70%) were achieved and the drug release rates were found to be pH-dependent. Cytotoxicity, confocal microscopy, and flow cytometry experiments against different types of cancerous cells indicated that Dox-loaded IO-MMNs reduced the viability of metastatic MCF-7 and KAIMRC-1 breast as well as HT-29 colon cancer cells, with the least uptake and toxicity towards normal primary cells (up to 4-fold enhancement). These results strongly suggest the potential use of IO-MMNs as promising agents for enhanced and effective drug delivery in cancer theranostics.
RESUMEN
PURPOSE: To determine whether the optical coherence tomography location of a subfoveal fibrovascular scar is correlated with visual outcome in eyes successfully treated with antivascular endothelial growth factor agents for neovascular age-related macular degeneration. METHODS: Fifty-six eyes from 56 patients with a subfoveal disciform scar after antivascular endothelial growth factor treatment were included. The initial and final visual acuity, fluorescein angiography, and spectral domain optical coherence tomography scar characteristics were retrospectively reviewed. RESULTS: Thirty-five of 56 eyes (62.5%) were classified as having entirely subretinal pigment epithelial (sub-RPE) scars, and 21 eyes (37.5%) had subretinal component scars. Mean initial visual acuity was similar between sub-RPE and subretinal scars (20/100 vs. 20/125, P = 0.517); mean final visual acuity was better in the sub-RPE scar group (20/60 vs. 20/200, P = 0.001). Eyes with sub-RPE scar had better preservation of the external limiting membrane, ellipsoid layer, and retinal thickness (P < 0.001, P = 0.017, P = 0.004, respectively) than subretinal component scar eyes. There was no difference between the groups in scar thickness or scar area (P = 0.707, P = 0.186, respectively). CONCLUSION: Sub-RPE location of subfoveal scarring in eyes treated for neovascular age-related macular degeneration is associated with better preservation of outer retinal structures and better vision, when compared with a subretinal scar.