Sentences with phrase «of photoreceptor»

The gene product's precise role is not currently understood but it is thought to anchor regulatory complexes at the photoreceptor connecting cilium, which acts as a bridge between the inner and outer segments of photoreceptor cells [43] as well as having functions in disk morphogenesis [42] and in the structure of the ciliary axoneme [44].

The eyes contain two different types of photoreceptor cells that affect the way everyone sees things, and this is true of both dogs and people.

The retina is normal when viewed with an ophthalmoscope, but there is a loss of photoreceptor activity as evidenced by a diminished electroretinogram (ERG).

Although this polymorphism was originally suspected as a cause of Photoreceptor Dysplasia (PD) in the Miniature, further research revealed that the polymorphism appears to be benign and has no association with retinal disease — including PD and PRA (unpublished data).

To describe the course of photoreceptor disease in canine X-linked retinal degeneration.

Researchers have found that another type of photoreceptor is responsible for regulating melatonin production in the retina.

However, the evidence from the past decade or so has revealed a third class of photoreceptor within the eye; intrinsically photosensitive retinal ganglion cells (ipRGCs), which express their own distinct opsin — melanopsin [6,7].

Phagocytosis of photoreceptor outer segments was defined by the inclusion of rhodopsin - labelled material within the TRA -1-85-bordered intracellular compartment of grafted human iPS - RPE cells.

Inset shows higher resolution confocal images of photoreceptor cell nuclear layers (DAPI blue) and rhodopsin expression (red) in the dystrophic control (left inset) and dystrophic with iPS - RPE transplant (right inset) RCS rat.

In addition to this, the gene duplicates in zebrafish display strikingly different expression during the day - night cycle, presumably to allow efficient regulation of photoreceptor cells under dramatically different light conditions.

Light is known to induce nuclear c - Fos expression in the INL of the mouse retina, however this response is reduced in a mouse model of photoreceptor degeneration [34].

This Clinical Statement provides recommendations for patients with inherited retinal degenerations, which comprise a wide range of genetically and phenotypically heterogeneous diseases associated with progressive loss of photoreceptor function and visual loss.

This work, appearing March 23 in Science, also suggests that when the first ancestral primate inherited a new type of photoreceptor more than 40 million years ago, it probably experienced immediate color enhancement, which may have allowed this trait to spread quickly.

Qualitative examination of the host anatomical response to the presence of hNPCctx or hNPCctx - GDNF revealed substantial preservation of the photoreceptor outer nuclear layer (ONL) overlying all subretinal donor cells (Figure 5E and F), with photoreceptor rescue gradually declining outside the distribution of the transplanted cells (Figure 5E and G).

Of note, while vision rescue requires preservation of some functional photoreceptors, the mere presence of photoreceptor cells in the ONL of transplanted RCS rats does not assure function [61].

In order to study rescue effects following surgery, donor cells were introduced at P21, an age preceding major onset of photoreceptor loss.

One can imagine that loss of function of any of the gene products along this complex pathway could lead to severe consequences for the survival of the photoreceptor (PR) cells in the eye.

Photoreceptor inner segments (IS) are visible above the pigmented donor cell layer, demonstrating partial preservation of photoreceptor structure.

While preservation of the ONL is evidence for a neuroprotective role for hNPCctx and GDNF within the retina, maintenance of visual function at the level observed in this study suggests at least partial retention of photoreceptor structure necessary for visual processing, particularly that associated with cones.

Quantitative fine - tuning of photoreceptor cis - regulatory elements through affinity modulation of transcription factor binding sites.

0 Research ArticleRETINAL DISEASES Human ESC — derived retinal epithelial cell sheets potentiate rescue of photoreceptor cell loss in rats with retinal degeneration Karim Ben M'Barek 1,2,3, Walter Habeler1, 2,3, Alexandra Plancheron1, 2,3,

«Many retinal diseases are manifested by the degeneration of photoreceptor cells.»

All of these diseases involve the death of photoreceptor cells and each is caused by a distinct genetic mutation.

They assessed gene activity at time points known to correspond with key phases of disease: the «induction phase,» the time before the peak level of photoreceptor cell death; the «execution phase,» when the highest rates of photoreceptor cell death occur; and the «chronic phase,» during which photoreceptor cell death continues at somewhat reduced levels.

However, by the time these mice reached adulthood, around 8 months old, the level of photoreceptor cells in these knockout mice was less than half the normal level.

«But in this case, the photoreceptor cells are fine in the beginning, so the death of the photoreceptor cells is a secondary affair that is somehow driven by the deficiency in horizontal cells,» he says.

But what scientists did not know is how the mutations trigger a molecular signaling pathway that leads to the death of photoreceptor cells.

If a new kind of photoreceptor appeared in the retina but the brain didn't process anything differently, «how could that new mutation get propagated through the population?»

This implant makes use of bipolar cells, as these form the second layer downstream of photoreceptor cells lost to the progress of disease.

What are the energy implications of photoreceptor genes?

«This is important because the death of photoreceptor cells is known to cause retinal degenerative diseases in humans that lead to blindness.

Rods and cones [photoreceptors in the eye] could not account for this differential regulation of melatonin production, so we postulated another type of photoreceptor was responsible for mediating such physiological responses.

Their findings suggest that even the earliest animals had the makings of both vertebrate and invertebrate visual systems, and that some of the photoreceptor cells in the invertebrate brain were transformed through a series of steps into vertebrate eyes.

In the centre of your retina is a dense patch of photoreceptor cells about 1 millimetre across.

«If we could perhaps modulate these pathways and prolong survival of photoreceptor cells, we might be able to delay any further degeneration even when intervening at these later stages of disease.»

Mutations in at least 60 genes are known to cause the disease, and many people are not diagnosed until after a a substantial proportion of photoreceptor cells, the eye's rods and cones, have already degenerated and died.

Tamoxifen provides structural and functional rescue in murine models of photoreceptor degeneration.

The six previously known fly rhodopsins account for the full function of photoreceptor cells in the fly's eyes, so although the fruit fly genome contained the sequence of a seventh rhodopsin, the role of Rh7 was unclear.

Color vision is generally carried out through the number of photoreceptor types found in the retina.

«The goal is to halt the rate of photoreceptor loss,» says Robert Lanza, chief scientist at Advanced Cell Technology (ACT) of Worcester, Massachusetts, the company that has been developing the treatment since first turning hESCs into RPEs in 2004.

Ironically, Neitz had once rejected this idea because it failed to explain why people lacking a certain type of photoreceptor still showed normal sensitivity when exposed to that shade of light.

It took nearly eight decades for scientists to investigate his claim and prove him right: The eye really does contain a third type of photoreceptor cells that sense light intensity without detecting images.

PRA is caused by the degeneration of the photoreceptor cells, rods and cones, which are needed for dark and day light vision, respectively.

«The loss of photoreceptor cells affects virtually all of us.»

Among the disorders that Balasubramanian has targeted is retinitis pigmentosa, a group of inherited diseases that cause degeneration of the retina (in the back of the eye where millions of photoreceptors capture light rays that the brain turns into images).

The answer, says a report in the 1 November issue of Science, lies in the genetic makeup of persons suffering from a partial loss of photoreceptors.

Right now scientists can only speculate what it might be like to wear an artificial retina with millions of photoreceptors in a regular grid, but such a device would not restore the experience of vision — no matter how many electrodes it contains.

Like many animals, humans have three kinds of photoreceptors in their eyes, each sensitive to a different colour.

«By putting in healthy cells, we can basically stop and prevent the degeneration of the photoreceptors,» says Sally Temple, the co-founder and scientific director of the Neural Stem Cell Institute in Rensselaer, N.Y.

Part of the process of seeing color is that three different kinds of photoreceptors in the eye are tuned to three overlapping families of color: red, green and blue (which are activated by visible light of long, medium and short wavelengths).