Retinal transplants bear threefold fruit

Darkfrog submitted, created time 3 months 4 weeks (www.nature.com)

A formerly clinically blind woman's vision improved from 20/800 to 20/160--from one-fortieth of ordinary vision to one-eighth--after receiving donated retina. Six months after the operation, the started noticing the pendulum in her grandfather clock. For years, she found that she could read large-print books and emails and returned to her hobbies, knitting and sewing. Now, six years after her operation, her vision is fading, but it is still better than it was before the operation

Submit comment | Blog It | Email It | Keywords: age-related macular degeneration opthalmology macular degeneration blindness stem cell research politics bioethics retinitis pigmentosa retina eyes sight vision transplants Vision Problems repair vision

Removal of "superfluous" retina creates (time) blind mice...

Darkfrog submitted, created time 6 months 3 weeks (www.nature.com)

Removing a certain type of retinal cell from lab mice doesn't make them go blind, but it does shake up their body clocks; they quickly slip into a 23.5 hour cycle--the same as unaltered mice in total darkness. They also lost their ability to regulate pupil size, but not their other visual abilities, such as judging how far to jump to make it across a gap. This suggests that these melanopsin-expressing retinal ganglion cells (mRGCs) concern the detection of light, not the processing of visual information.

What I'm curious about now is whether blind humans do or do not have this problem

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Shape encoding may start in the retina

carly submitted, created time 1 year 3 months (www.eurekalert.org)

New evidence from the University of Southern California suggests that there may be dedicated cells in the retina that help compile small bits of information in order to recognize objects. The research was conducted by Ernest Greene, professor of psychology in the area of brain and cognitive sciences at USC. The study is published in the Public Library of Science journal, PLoS ONE.

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Identification of a locus control region for quadruplicated green-sensitive opsin genes in zebrafish

bianjie submitted, created time 1 year 5 months (www.pnas.org)

Duplication of opsin genes has a crucial role in the evolution of visual system. Zebrafish have four green-sensitive (RH2) opsin genes (RH2-1, RH2-2, RH2-3, and RH2-4) arrayed in tandem. They are expressed in the short member of the double cones (SDC) but differ in expression areas in the retina and absorption spectra of their encoding photopigments.

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Color is in the eye of the beholder

bianjie submitted, created time 1 year 6 months (www.springer-sbm.com)

The unique makeup of the cells in our retina, as well as the specific physical properties of substances themselves, explain why we occasionally see things change color before our very eyes! Samo and Marko Kreft from the University of Ljubljana in Slovenia investigated this phenomenon using pumpkin seed oil as an example. They have just published their research online in Springer's journal Naturwissenschaften.

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Synaptic Ca2+ in Darkness Is Lower in Rods than Cones, Causing Slower Tonic Release of Vesicles

fiona submitted, created time 1 year 7 months (www.jneurosci.org)

"Rod and cone photoreceptors use specialized biochemistry to generate light responses that differ in their sensitivity and kinetics. However, it is unclear whether there are also synaptic differences that affect the transmission of visual information. Here, we report that in the dark, rods tonically release synaptic vesicles at a much slower rate than cones, as measured by the release of the fluorescent vesicle indicator FM1-43

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The Rise of Bionic Eyes

fiona submitted, created time 1 year 8 months (sciencenow.sciencemag.org)

"The trick to restoring vision in people blinded by injury or disease may be to bypass the eyes entirely. By establishing a connection between a video device and the part of the brain that receives visual stimuli, researchers have shown that the brain can interpret electronic signals in the same way it interprets light waves."

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Mapping of transcription start sites of human retina expressed genes

freeman submitted, created time 1 year 9 months (www.biomedcentral.com)

The proper assembly of the transcriptional initiation machinery is a key regulatory step in the execution of the correct program of mRNA synthesis. The use of alternative transcription start sites (TSSs) provides a mechanism for cell and tissue specific gene regulation. In silico and experimental analysis of the transcripts proved to be essential for the ultimate mapping of TSSs. The new TSSs and transcribed sequences are essential for further exploration of the promoter and other cis-regulatory sequences at the 5'end of genes.

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Cystine Inhibits Creatine Kinase Activity in Pig Retina

biscuits submitted, created time 1 year 10 months (www.arcmedres.com)

Scientists’s study in UFRGS in Brazil provide a possible mechanism for cystine toxicity and also another beneficial effect for the use of cysteamine in patients with cystinosis.

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Eye disease in diabetics tied to risk of dying

catherine submitted, created time 1 year 10 months (www.sciam.com)

In adults with type 2 diabetes, a common diabetes-related complication of the eye called retinopathy is associated with an increased risk of dying within in a given period of time, a study shows.

Retinopathy arises when diabetes damages the tiny blood vessels of the retina, the light-sensitive tissue at the back of the eye. It can lead to blurred vision and blindness if unchecked. In women, proliferative retinopathy was associated with a 2.9-fold increased risk of death from all causes

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