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Biology subjects

Vagni, P.

Publications and source records attributed to Vagni, P..

3 recordsLinked to original sources

All-polymeric transient neural probe for prolonged in-vivo electrophysiological recordings

Transient bioelectronics has grown fast, opening possibilities never thought before. In medicine, transient implantable devices are interesting because they could eliminate the risks related to surgical retrieval and reduce the chronic foreign body reaction. However, despite recent progress in this area, the short functional lifetime of devices due to short-lived transient metals, which is typically a few days or weeks, still limits the potential of transient medical devices. We report that a switch from transient metals to an entirely polymer-based approach allows for a slower degradation process and a longer lifetime of the transient probe, thus opening new possibilities for transient medical devices. As a proof-of-concept, we fabricated all-polymeric transient neural probes that can monitor brain activity in mice for a few months rather than a few days or weeks. Also, we extensively evaluated the foreign body reaction around the implant during the probes degradation. This kind of devices might pave the way for several applications in neuroprosthetics.

bioengineering↗

Gene editing preserves visual function in a mouse model of retinal degeneration

Inherited retinal dystrophies are a large and heterogeneous group of degenerative diseases caused by mutations in various genes. Given the favourable anatomical and immunological characteristics of the eye, gene therapy holds great potential for their treatment. We used a tailored CRISPR/Cas9-based gene editing system to prevent retinal photoreceptor death in the Rd10 mouse model of retinitis pigmentosa. We tested the gene editing tool in vitro and then used in vivo subretinal electroporation to deliver it to one of the retinas of mouse pups at different stages of photoreceptor differentiation. Three months after gene editing, the treated eye exhibited a higher visual acuity compared to the untreated eye. Moreover, we observed preservation of light-evoked responses both in explanted retinas and in the visual cortex of treated animals. Our study validates a CRISPR/Cas9-based therapy as a valuable new approach for the treatment of retinitis pigmentosa caused by autosomal recessive loss-of-function point mutations.

neuroscience↗

Optic nerve intraneural stimulation allows selective visual cortex activation

Retinal prostheses have been developed to restore a functional form of vision in patients affected by outer retinal layer dystrophies. Other approaches, namely optic nerve, thalamic, and cortical prostheses are under investigation to expand this toolbox both as clinical devices and as tools for fundamental research. Optic nerve stimulation is attractive since it bypasses the entire retinal network and directly activates nerve fibers. At the same time, it still takes advantage of the high-level information processing occurring downstream in the visual cortex. Here we show that a new intraneural electrode array (OpticSELINE) is effective in inducing the activation of the visual cortex upon electrical stimulation of the optic nerve. We also demonstrate that intraneural optic nerve stimulation induces selective cortical activation patterns depending on the stimulating electrode, thus suggesting that the OpticSELINE possesses spatial selectivity in fiber stimulation. In conclusion, the OpticSELINE can be used both as visual prosthesis for blind patients and as tool to further investigate the effect of the electrical stimulation in the visual system.

bioengineering↗