171 results about "Photoreceptor cell" patented technology

Disclosed is a system for maintaining normal health of photoreceptor cells and promoting regeneration of photoreceptor cells, and methods thereof. The system comprises: an implant capable of being implanted in a region in proximity to retina of an eye; and an electrical stimulation unit disposed in a region around the eye. The electrical stimulation unit induces an electrical current in the implant for electrical stimulation of the retina of the eye, thereby maintaining normal health of photoreceptor cells and promoting regeneration of photoreceptor cells in the retina.

The present study demonstrates that brimonidine tartrate, an alpha-2 adrenergic receptor agonist, can prevent photoreceptor cell degeneration and the associated Muller cell degenerative signs in an in vitro model of retinal degeneration and retinal detachment (separation of the neuroretina from the retinal pigment epithelium). Similar to control conditions, brimonidine allowed for the formation of highly structured photoreceptor outer segments, prevented the expression of stress markers in Müller cells and preserved the expression patterns of Muller cell markers of proper cell-cell contact and differentiation. Ultrastructural studies also indicated that brimonidine favored the formation of cell-cell junctions between photoreceptor cells and Müller cells, indicating that this phenomenon is associated with the exertion of the neuroprotective effect. The results suggest that brimonidine compounds may be utilized as an effective therapeutic agent for early and late onset retinal degenerations caused by defects in photoreceptor cells, Müller cells or both, and as an adjuvant to therapeutic success in retinal detachment surgery or macular translocation surgery for age-related macular degeneration.

The present invention is directed to VEGF-2 polynucleotides and polypeptides and methods of using such polynucleotides and polypeptides. In particular, provided are methods of treating retinal disorders with VEGF-2 polynucleotides and polypeptides.

The invention provides a human visual perception simulation-based self-adaptive low-illumination image enhancement method. The method is put forwards based on characteristics of low brightness and low contrast of a low-illumination color image and through researching an automatic adjustment process of pupils and photoreceptor cells for an environment. The method includes the following steps that: the adjustment process of the pupils for light is simulated, and the total brightness level of the image is improved; and the self-adaptive adjustment and control ability of eye vision for a low-illumination environment is simulated, and a nonlinear mapping model is designed to simulate the adjustment process of rod cells and cone cells, so that a bright and dark self-adaptation function can be obtained, and a bright and dark information fusing function is determined according to illumination distribution, and global self-adaptive adjustment is performed on brightness components; and the local contrast of the enhanced brightness image will be decreased, so that local self-adaptive contrast enforcement is performed on the image through adopting an exponential function; and finally, and color restoration is performed on the enhanced image. With the human visual perception simulation-based self-adaptive low-illumination image enhancement method of the invention adopted, the brightness, local contrast and detail information of the low-illumination color image can be effectively improved, and especially, the method has obvious effects in dark area and highlight area enhancement.

The invention provides a labeling composition for an intraocular tissue of a living individual, which specifically labels the intraocular tissue without need of an invasive operation such as exposure of an ocular tissue or injection of a staining agent into the ocular tissue or a nerve tissue linking to the ocular tissue, a method of noninvasively labeling an intraocular tissue of a living individual, and a screening method using the labeling composition for the intraocular tissues. The composition contains a compound capable of labeling at least a photoreceptor cell layer of a retina, wherein the compound is a staining compound having a particular structure as a partial structure thereof.

The invention relates to methods, cells and nucleic acids for making transgenic animals. The methods generally comprise introducing into a genome of an animal a genetic construct comprising a transcriptional regulatory element operably linked to a heterologous marker gene encoding a marker, wherein the element drives expression of the marker across genera transgenic in the construct sufficient to visually detect the marker in photoreceptive cells or organs, and selecting for transgenesis by visually detecting the marker in a photoreceptive cell or organ of the animal.

Disclosed is a composition for inducing the proliferation of retinal cells or the differentiation of retinal progenitor cells into retinal cells. The composition, similar to in vivo conditions for development during embryogenesis, induces stem cells to differentiate into a multitude of photoreceptor cells at high yield within a short period of time, without an additional gene transfer. In addition, the differentiated photoreceptor cells are useful in cellular therapy because they, when transplanted into degenerated or injured retinas, can be engrafted and fused within the retinas to prevent or cure retinal degeneration.

Methods are provided for the production of photoreceptor cells and photoreceptor progenitor cells from pluripotent stem cells. Additionally provided are compositions of photoreceptor cells and photoreceptor cells, as well as methods for the therapeutic use thereof. Exemplary methods may produce substantially pure cultures of photoreceptor cells and / or photoreceptor cells.

The invention discloses a construction method for a model of animals with retinitis pigmentosa diseases and application and relates to the technical field of medical engineering. According to the construction method for the model of the animals with the retinitis pigmentosa diseases, Hkdcl gene sequences on genomes of target animals are knocked out, the model of the animals with the retinitis pigmentosa diseases is obtained, the model of the animals presents typical characteristics, such as retina function damage and gradualness apoptosis of photoreceptor cells, of retinitis pigmentosa, the model of the animals can be applied to research of the retinitis pigmentosa diseases and medicine for screening treatment of the retinitis pigmentosa diseases, and the method has wide application prospects.

The invention relates to imparting photoreactivity to target cells, e.g., retinal cells, by introducing photoresponsive functional abiotic nanosystems (FANs), nanometer-scale semiconductor / metal or semiconductor / semiconductor hetero-junctions that in this case include a photovoltaic effect. The invention further provides methods of making and using FANs, where the hetero-junctions bear surface functionalization that localizes them in cell membranes. Illumination of these hetero-junctions incorporated in cell membranes generates photovoltages that depolarize the membranes, such as those of nerve cells, in which FANs photogenerate action potentials. Incorporating FANs into the cells of a retina with damaged photoreceptor cells reintroduces photoresponsiveness to the retina, so that light creates action potentials that the brain interprets as sight.

Disclosed are novel methods of treatment for retinal diseases and conditions including age-related macular degeneration, genetic-based retinal degenerations and retinal detachment. A novel glycan binding protein thought to be a cell surface receptor has been discovered in the retina. The retinal glycan binding receptor is shown to play an important role in promoting assembly of outer segment (OS) membranes by the photoreceptor cells of the eye, a process that is essential for vision. Based on the finding that certain sugars can bind with very high affinity to the retinal glycan receptor and stimulate its function, the invention provides novel therapeutic agents for treatment of retinal diseases that are multivalent N-linked glycans. Preferred pharmaceutical compositions in accordance with the present invention comprise active agents having the general formula: (Gal-GlcNAc)n-Man3-GlcNAc2, where n is 1-4. Particularly preferred multivalent glycans are galactosylated, biantennary (NA2), and asialo, galactosylated, triantennary (NA3) oligosaccharides.

Described herein are methods of preventing, arresting progression of or ameliorating vision loss and other conditions associated with retinitis pigmentosa and x-linked retinitis pigmentosa in a subject. The methods include administering to a subject an effective concentration of a composition comprising a recombinant adeno-associated virus (AAV) carrying a nucleic acid sequence encoding a normal retinitis pigmentosa GTPase regulator (RPGR gene), or fragment thereof, under the control of regulatory sequences which express the product of the gene in the photoreceptor cells of the subject, and a pharmaceutically acceptable carrier.