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Retinal degeneration is one of the prevalent causes of blindness worldwide, for which no effective treatment has yet been identified. Inorganic photovoltaic devices have been investigated for visual restoration in advanced stage Retinitis pigmentosa (RP), although lack of implant flexibility and foreign‐object reactions have limited their application. Organic photoactive retinal prostheses may overcome these limitations, being biomimetic and tissue friendly. Inspired by organic photovoltaic strategies involving graphene, a hybrid retinal prosthesis is recently engineered consisting of a dual poly‐3‐hexylthiophene (P3HT) and graphene layer onto a flexible substrate. Here, this hybrid prosthesis is subretinally implanted in vivo in 5‐month‐old Royal College of Surgeons (RCS) rats, a rodent model of RP. Implanted dystrophic rats restored visual performances at both subcortical and cortical levels in response to light stimuli, in the absence of marked inflammatory responses. Moreover, the analysis of the physical‐mechanical properties after prolonged permanence in the eye showed excellent biocompatibility and robustness of the device. Overall, the results demonstrate that graphene‐enhanced organic photovoltaic devices can be suitably employed for the rescue of retinal dystrophies and supports the translation of the organic strategy into medical practice. [ABSTRACT FROM AUTHOR]

Abstract: BACKGROUND: The present study evaluated a biocompatible material for plant protection with the aim of reducing the amount of active substance applied. We used a synthetic hydroxyapatite (HA) that has been studied extensively as a consequence of its bioactivity and biocompatibility. An aggregation between HA nanoparticles and four Cu(II) compounds applied to Vitis vinifera L. leaves as a pesticide was studied. Formulations were characterized by X‐ray diffraction (XRD), dynamic light scattering (DLS) and electron microscopy and applied in planta to verify particle aggregation and efficiency in controlling the pathogen Plasmopara viticola. RESULTS: The XRD patterns showed different crystalline phases dependig on the Cu(II) compound formulated with HA particles, DLS showed that nanostructured particles are stable as aggregates out of the nanometer range and, in all formulations, transmission electron microscopy (TEM) and environmental scanning electron microscopy (ESEM) microscopy showed large aggregates which were partially nanostructured and were recognized as stable in their micrometric dimensions. Such particles did not show phytotoxic effects after their application in planta. CONCLUSION: A formulation based on HA and a soluble Cu(II) compound showed promising results in the control of the fungal pathogen, confirming the potential role of HA as an innovative delivery system of Cu(II) ions. The present work indicates the possibility of improving the biological activity of a bioactive substance by modifying its structure through an achievable formulation with a biocompatible material. © 2018 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Purpose: Human cord blood serum (CBS) is enriched with neurotrophins endowed of neuroprotective functions. Muller cells orchestrate retinal functioning, but their hyper‐activation can exacerbate retinal damage under oxidative stress, which typically occurs during neurodegenerative diseases. In this study we tested whether CBS could regulate human Muller cell activation under H2O2‐ and IL‐1□‐ induced damage. Methods: Selected neurotrohpins (BDNF, TGF‐□, NGF, GDNF, EGF) were analysed in CBS (Human Magnetic Luminex Screening Assay). The human Muller cell line Moorfields/Institute of Ophtalmology‐Muller 1 (MIO‐M1) was obtained from the UCL Institute of Ophtalmology, London, UK1. MIO‐M1 were seeded in growth media enriched with standard FBS or CBS, both at 5%. After 24 h, MIO‐M1 were exposed to H2O2 and IL‐1□ for 24 h. CBS effects were compared to FBS control cells in terms of cell survival (MTT assay), activation (GFAP mRNA) and inflammation (TNF‐□ and IL‐6 mRNA). Results: Median levels of neurotrophins in CBS were: BDNF 1.5 ng/ml, NGF 3.0 pg/ml, GDNF 1.5 pg/ml, TGF‐□ 36.3 pg/ml, EGF 820 pg/ml. MIO‐M1 pre‐cultured with CBS and exposed to H2O2, underwent a 50% decrease of GFAP mRNA in comparison to FBS control cells. CBS also mitigated the inflammatory activation, as shown by a significant 50% reduction of IL‐6 and TNF‐□ mRNA levels. The CBS ability to modulate the inflammatory pathway was confirmed by the significant decrease of IL‐6 and TNF‐□ genes (6‐ and 4‐ fold lower than FBS, respectively) in MIO‐M1 exposed to IL‐1□ (50 ng/ml). Conclusion: CBS protects retinal Muller cells from damage under in vitro stress conditions. The main targets of this neuroprotecting stretegy are GFAP, marker of Muller cell activation, and the inflammatory cytokines, closely related to the neurodegenerative diseases. Therefore, CBS represents a promising therapeutic agent for the neurodegenerative diseases and further studies are necessary to validate this issue. Reference Limb GA et al. 2002, IOVS, 43; 864–869. [ABSTRACT FROM AUTHOR]