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Concept

Photorécepteur (biologie)

Publications associées (30)

Ultraviolet Superradiance from Mega-Networks of Tryptophan in Biological Architectures

Majed Chergui, Katrin Elisabeth Oberhofer

Networks of tryptophan (Trp)& horbar;an aromatic amino acid with strong fluorescence response & horbar;are ubiquitous in biological systems, forming diverse architectures in transmembrane proteins, cytoskeletal filaments, subneuronal elements, photorecepto ...

Amer Chemical Soc2024

Neuroprotection in the Retina: From Preventing Inflammatory Cell Death to Promoting Vascular Stability in the Central Nervous System

Bokyoung Kim

Glaucoma is one of the leading causes of irreversible blindness worldwide. Glaucoma is defined clinically as the presence of optic nerve head (ONH) degeneration and progressive loss of retinal ganglion cells (RGCs). Intra-ocular pressure (IOP) has been con ...

EPFL2024

Distinct ultrastructural phenotypes of glial and neuronal alpha-synuclein inclusions in multiple system atrophy

Henning Paul-Julius Stahlberg, Marta Di Fabrizio, Amanda Jennifer Lewis, Domenic Burger

Multiple System Atrophy is characterized pathologically by the accumulation of alpha-synuclein (aSyn) into glial cytoplasmic inclusions (GCIs). The mechanism underlying the formation of GCIs is not well understood. In this study, correlative light and elec ...

2024

Neuronal migration prevents spatial competition in retinal morphogenesis

Martin Weigert

The concomitant occurrence of tissue growth and organization is a hallmark of organismal development(1-3). This often means that proliferating and differentiating cells are found at the same time in a continuously changing tissue environment. How cells ada ...

NATURE PORTFOLIO2023

Colloidal self-assembly of soft neural interfaces from injectable photovoltaic microdevices

Mahmut Selman Sakar, Zhangjun Huang, Murat Kaynak, Haiyan Jia

Biomimetic retinas with a wide field of view and high resolution are in demand for neuroprosthetics and robot vision. Conventional neural prostheses are manufactured outside the application area and implanted as a complete device using invasive surgery. He ...

2023

Continuous Simulation Data Stream: A dynamical timescale-dependent output scheme for simulations

Loïc Hausammann

Exa-scale simulations are on the horizon but almost no new design for the output has been proposed in recent years. In simulations using individual time steps, the traditional snapshots are over resolving particles/cells with large time steps and are under ...

ELSEVIER2022

POLYRETINA restores light responses in vivo in blind Gottingen minipigs

Diego Ghezzi, Marta Jole Ildelfonsa Airaghi Leccardi, Paola Vagni, Elodie Geneviève Zollinger, Charles-Henri Puncho Jérôme Vila, Golnaz Sherafatipour

Retinal prostheses hold potential for artificial vision in blind people. Here, authors show that POLYRETINA, a large and high-density photovoltaic epiretinal device, restores light-evoked cortical responses in blind Gottingen minipigs at safe irradiance le ...

Nature Portfolio2022

Incomplete Recovery of Zebrafish Retina Following Cryoinjury

Dylan Lawless

Zebrafish show an extraordinary potential for regeneration in several organs from fins to central nervous system. Most impressively, the outcome of an injury results in a near perfect regeneration and a full functional recovery. Indeed, among the various i ...

MDPI2022

Molecular profiling of stem cell-derived retinal pigment epithelial cell differentiation established for clinical translation

Gioele La Manno, Irina Khven, Alex Russell Lederer

Human embryonic stem cell-derived retinal pigment epithelial cells (hESC-RPE) are a promising cell source to treat age-related macular degeneration (AMD). Despite several ongoing clinical studies, a detailed mapping of transient cellular states during in v ...

CELL PRESS2022

Three-dimensional multilayer concentric bipolar electrodes restrict spatial activation in optic nerve stimulation

Diego Ghezzi, Marta Jole Ildelfonsa Airaghi Leccardi, Eleonora Borda, Vivien Gaillet, Elodie Geneviève Zollinger

Objective. Intraneural nerve interfaces often operate in a monopolar configuration with a common and distant ground electrode. This configuration leads to a wide spreading of the electric field. Therefore, this approach is suboptimal for intraneural nerve ...

IOP Publishing Ltd2022

Homogeneous light stimulation of melanopsin and cones with a Maxwellian view device for the human eye

Patrick Robert Flückiger, Gilles Evéquoz

We designed and tested a device to stimulate specifically one photoreceptor type, or a combination of some of them, of the human eye by using up to six primaries. The device produces a homogeneous light field over 40 degrees which is projected onto the ret ...

IEEE2021

Features integrate along a motion trajectory when object integrity is preserved

Michael Herzog, Leila Drissi Daoudi - Kleinbauer

Information about a moving object is usually poor at each retinotopic location because photoreceptor activation is short, noisy, and affected by shadows, reflections of other objects, and so on. Integration across the motion trajectory may yield a much bet ...

Association for Research in Vision and Ophthalmology (ARVO)2021

Organic semiconductors for light-mediated neuromodulation

Diego Ghezzi, Danashi Imani Medagoda

There is growing interest in organic semiconductor devices for light-mediated neuromodulation, such as for retinal stimulation. Here, the key working principles of these devices are discussed, as well as promising applications and outstanding challenges fo ...

SPRINGERNATURE2021

Photovoltaic stimulation of retinal microcircuit for vision restoration

Naïg Aurelia Ludmilla Chenais

Sight restoration through retinal prostheses was still a mere dream a century ago. Current challenges are even greater: providing a quantitatively and qualitatively useful artificial vision to late blind patients. Existing approaches all face engineering a ...

EPFL2021

Photovoltaic retinal prosthesis restores high-resolution responses to single-pixel stimulation in blind retinas

Diego Ghezzi, Marta Jole Ildelfonsa Airaghi Leccardi, Naïg Aurelia Ludmilla Chenais

Retinal prostheses hold the promise of restoring vision in totally blind people. However, a decade of clinical trials highlighted quantitative limitations hampering the possibility of reaching this goal. A key challenge in retinal stimulation is to indepen ...

2021

Development of a new visual prosthesis for preclinical studies on artificial vision

Marta Jole Ildelfonsa Airaghi Leccardi

The technological evolution in materials science and microengineering favored the production of advanced visual prostheses useful for fighting blindness and to improve patients quality of life. Visual prostheses aim at replacing lost visual functions by ar ...

EPFL2020

Naturalistic spatiotemporal modulation of epiretinal stimulation increases the response persistence of retinal ganglion cell

Diego Ghezzi, Marta Jole Ildelfonsa Airaghi Leccardi, Naïg Aurelia Ludmilla Chenais

Objective. Retinal stimulation in blind patients evokes the sensation of discrete points of light called phosphenes, which allows them to perform visually guided tasks, such as orientation, navigation, object recognition, object manipulation and reading. H ...

2021

Single particle cryo‐EM of the complex between interphotoreceptor retinoid‐binding protein and a monoclonal antibody

Henning Paul-Julius Stahlberg

Interphotoreceptor retinoid‐binding protein (IRBP) is a highly expressed protein secreted by rod and cone photoreceptors that has major roles in photoreceptor homeostasis as well as retinoid and polyunsaturated fatty acid transport between the neural retin ...

2020

In vivo evaluation of gene editing and prosthetic strategies to restore vision in small and large animal models of retinal degeneration

Paola Vagni

Inherited retinal diseases (IRDs) form a group of diverse disorders that lead to the degeneration of the light-sensing cells of the retina: the photoreceptors. IRDs are among the leading causes of blindness in working-age adults living in industrialized co ...

EPFL2020

Optical phase contrast imaging of human retinal cells by changing the tissue refractive index

Christophe Moser, Timothé Laforest, Laura Emmanuelle Kowalczuk, Mathieu Künzi

Purpose : Based on oblique partially coherent illumination of transparent samples, we developed a simple custom Optical Phase Imaging (OPI) microscope providing a label-free, semi-quantitative phase contrast imaging. The aim of this study was to explore th ...

ASSOC RESEARCH VISION OPHTHALMOLOGY INC2020