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Components in neural implants, such as the electrode array and stimulator circuit, are often fabricated discretely. This modular fabrication scheme offers flexibility during development but poses difficulties during assembly, as components must be compactly integrated for implantation. It is particularly difficult in cases where the electrode array is required to have a high number of channels, such as in retinal prostheses. This paper presents the development of a parylene C‐based, double‐sided microelectrode array with 294 hemispheric electrodes for subretinal stimulation. The bonding pads on the bottom side of the double‐sided array are connected with electrodes through vias, eliminating the interconnection lines. The array can be integrated with a stimulator circuit through pad‐to‐pad bonding, resulting in a compact implant. The hemispheric electrodes are fabricated using thermally reflowed photoresist infillings, through which the height and width of the hemispheres can be easily controlled. The long‐term stability and biocompatibility of the materials and methods used to fabricate and package the electrodes are demonstrated in in vitro and in vivo environments over months. Finally, subretinal stimulation by the developed electrodes is successfully demonstrated using in vitro retinal patches from mice and monkeys. [ABSTRACT FROM AUTHOR]

Postsynthetic modifications (PSMs) of metal–organic frameworks (MOFs) play a crucial role in enhancing material performance through open metal site (OMS) functionalization or ligand exchange. However, a significant challenge persists in preserving open metal sites during ligand exchange, as these sites are inherently bound by incoming ligands. In this study, for the first time, we introduced alkoxides by exchanging bridging chloride in Ni2Cl2BTDD (BTDD=bis (1H‐1,2,3,–triazolo [4,5‐b],–[4′,5′‐i]) dibenzo[1,4]dioxin) through PSM. Rietveld refinement of synchrotron X‐ray diffraction data indicated that the alkoxide oxygen atom bridges Ni(II) centers while the OMSs of the MOF are preserved. Due to the synergy of the existing OMS and introduced functional group, the alkoxide‐exchanged MOFs showed CO2 uptakes superior to the pristine MOF. Remarkably, the tert‐butoxide‐substituted Ni_T exhibited a nearly threefold and twofold increase in CO2 uptake compared to Ni2Cl2BTDD at 0.15 and 1 bar, respectively, as well as high water stability relative to the other exchanged frameworks. Furthermore, the Grand Canonical Monte Carlo simulations for Ni_T suggested that CO2 interacts with the OMS and the surrounding methyl groups of tert‐butoxide groups, which is responsible for the enhanced CO2 capacity. This work provides a facile and unique synthetic strategy for realizing a desirable OMS‐incorporating MOF platform through bridging ligand exchange. [ABSTRACT FROM AUTHOR]

Objectives: To investigate the characteristics of margin reflex distance 1 (MRD1) asymmetry in congenital lower eyelid epiblepharon and its resolution after surgical correction of epiblepharon. Methods: Among patients who underwent lower eyelid epiblepharon surgery from November 2015 to September 2017, patients with a preoperative MRD1 difference of more than 1.0 mm between the two eyes according to medical photographs were defined as having MRD1 asymmetry. A postoperative MRD1 difference of less than 1.0 mm between the two eyes was regarded as MRD1 asymmetry resolution. The preoperative MRD1 difference was compared between subgroups with resolved or sustained MRD1 asymmetry. Astigmatism and amblyopia were also assessed. Results: Among 432 patients, MRD1 asymmetry was observed in 24 patients (5.6%). MRD1 was always lower in the side with more extensive epiblepharon. At 6 months after surgery, the mean MRD1 difference between the two eyes was significantly decreased (1.8 ± 0.7 mm to 0.5 ± 0.8 mm, p <.001, paired t-test) and MRD1 asymmetry resolution occurred in 19 patients (79%). In the resolved MRD1 asymmetry group, the preoperative MRD1 difference was 2.0 mm or less and was significantly smaller than that in the sustained MRD1 asymmetry group (p =.010, Mann-Whitney U test). Six patients had preoperative aniso-astigmatism ≥ 1.50 D. Unilateral amblyopia presented in nine patients (38%) and improved within 1 year postoperatively. Conclusions: MRD1 asymmetry can be resolved after epiblepharon surgery, especially when the preoperative MRD1 difference is 2.0 mm or less. Unilateral amblyopia was frequent, but the treatment outcome was good. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the toxicity of type I interferons (IFNs) on the ocular surface and assess their efficacy in ocular surface tumors., Methods: We examined the effects of IFN-α2a, IFN-α2b and IFN-β on corneal epithelial cells and stromal fibroblasts in vitro as well as the impact of IFN-α2a on the ocular surface in mice. Additionally, we analyzed the therapeutic and adverse effects of topically administered IFN-α2a and IFN-α2b in patients with ocular surface tumors. Risk factors contributing to side effects were explored., Results: IFN-α2a, IFN-α2b or IFN-β reduced cell viability and induced pro-inflammatory cytokines in corneal epithelial cells and stromal fibroblasts. Furthermore, IFNs enhanced the expression of major histocompatibility complex class II and CD40 in corneal epithelial cells. In mice, subconjunctival IFN-α2a injection did not induce corneal epithelial defects or opacity, nor did it reduce aqueous tears or conjunctival goblet cells. In patients, topical IFN-α2a or IFN-α2b administration decreased tumor size and prevented recurrence; however, it was associated with mild side effects, including corneal epitheliopathy and conjunctival hyperemia. These complications were associated with longer IFN use, the presence of underlying ocular surface disease and concurrent use of mitomycin C or anti-glaucoma eye drops., Conclusion: Although type I IFNs cause direct toxicity on corneal cells, they do not induce significant side effects on the healthy ocular surface. Considering its therapeutic and preventive effects, topical type I IFN is safe and effective for treating ocular surface tumors. The potential for ocular side effects should be considered in eyes with identified risk factors., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Postsynthetic modifications (PSMs) of metal-organic frameworks (MOFs) play a crucial role in enhancing material performance through open metal site (OMS) functionalization or ligand exchange. However, a significant challenge persists in preserving open metal sites during ligand exchange, as these sites are inherently bound by incoming ligands. In this study, for the first time, we introduced alkoxides by exchanging bridging chloride in Ni 2 Cl 2 BTDD (BTDD=bis (1H-1,2,3,-triazolo [4,5-b],-[4',5'-i]) dibenzo[1,4]dioxin) through PSM. Rietveld refinement of synchrotron X-ray diffraction data indicated that the alkoxide oxygen atom bridges Ni(II) centers while the OMSs of the MOF are preserved. Due to the synergy of the existing OMS and introduced functional group, the alkoxide-exchanged MOFs showed CO 2 uptakes superior to the pristine MOF. Remarkably, the tert-butoxide-substituted Ni&#95;T exhibited a nearly threefold and twofold increase in CO 2 uptake compared to Ni 2 Cl 2 BTDD at 0.15 and 1 bar, respectively, as well as high water stability relative to the other exchanged frameworks. Furthermore, the Grand Canonical Monte Carlo simulations for Ni&#95;T suggested that CO 2 interacts with the OMS and the surrounding methyl groups of tert-butoxide groups, which is responsible for the enhanced CO 2 capacity. This work provides a facile and unique synthetic strategy for realizing a desirable OMS-incorporating MOF platform through bridging ligand exchange., (© 2024 Wiley-VCH GmbH.)