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THE MAGNIFIER - Electronic Newsletter
Issue #5, August 2, 2000
Produced by: Macular Degeneration Foundation
P.O. Box 9752, San Jose, CA 95157
http://www.eyesight.org
CONTENTS
1. ARVO CONFERENCE
2. NEW WEB SITE FEATURES
3. YOUR INPUT
4. INTERNET HINTS
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1. ARVO CONFERENCE
ARVO Presents a Vision of Hope for Improved Sight
Each year in Fort Lauderdale, Florida over 8,000 of the World's top ophthalmologists and
eye researchers gather for the biggest meeting of the year to report new knowledge about the eye and update colleagues on important developments in ophthalmology practice.
It's the Annual Meeting of the venerable Association
for Research in Vision and Ophthalmology (ARVO).
The Macular Degeneration Foundation was there, listening, learning and engaging the best and the brightest researchers in discussion about ways to achieve sight saving
solutions sooner.
While the bulk of papers presented still focussed on eye diseases other than macular degeneration, there was an encouraging increase in the amount of work being done in MD.
The MD research reported fell into three categories:
1. Developing a better understanding of what goes right in the normal macula and what goes wrong in a diseased one.
2. Determining the structure and function of the
newly discovered genes linked to Stargardt and some forms of macular degeneration
3. Looking at ways to stimulate the macula to repair itself using stem cells
New Insights into What Goes Wrong
ARVO Researchers
shared new facts about age-related changes to Bruch's membrane (BM), the fine tissue layer that is sandwiched between the macular blood supply and the retinal pigment epithelium (RPE), the sponge like layer that supplies nutrients
and oxygen to the macular cones (sight sensing cells).
First, scientists at Wilmer Eye Institute announced that they had created a potential mouse model for degeneration of the RPE, and the BM using a breed of mice that
undergo accelerated aging, known as senescence accelerated mice. The mice were induced to show some of the neovascular (new blood vessel) changes that humans with the wet from of macular degeneration have. The implications of this
work for humans with the disease are that we may now have a better animal model to study the disease and test new therapies in an accelerated fashion.
Is drusen the battle-scar from a war you wage with your own macula?
The origin of drusen, remains a complex mystery, but three papers from prominent research groups in Santa Barbara, Iowa and Sydney Australia suggested that some drusen might well be the fallout from an immune attack launched by
your own body against exposed areas of the RPE or BM .
The theory - something disrupts the normal integrity of these structures. Then the body's immune system attacks the tissues in the breached area as if it were a foreign
invader, creating mounds of dead material and immune complexes that appear as drusen. More research is required to further define this process. The hope is that it may be possible to develop and use targeted medicines that control
excessive immune responses to minimize drusen formation in carefully selected cases.
Activated Enzymes show Promise as Primers of Pumps that clear Debris from the Macula
Scientists at St. Thomas Hospital in London
presented tantalizing evidence that a class of human enzymes called matrix metalloproteases (MMP's) could increase flow across the BM. This improved pump function would prevent the build-up of waste products in the BM that are
believed to contribute to drusen.
One specific variant called MMP-9 was more effective that others in the family. MMP's are abundant in younger people but tend to diminish with age. The researchers suggested that MMP-9 may
one day be useful as a medicine to prevent or treat macular degeneration.
The Controversy Continues - are Stargardt and AMD Genes the same?
As more and more geneticists weigh into the fray, conflicting studies were
presented, with Australian researchers reporting no association between the same mutations seen in ABCR gene of Stargardt patients and those of AMD patients.
The ABCR gene is responsible for manufacturing the ABCR
transporter protein previously discovered in rod (black and white) photoreceptors, malfunction of which is implicated in juvenile macular degeneration or Stargardt disease.
However, other studies in China and Canada continue
to demonstrate an association. Several larger studies are now under way hoping to resolve the controversy and provide a more detailed map of areas of the ABCR gene that may be the most appropriate targets for investigation.
Importantly, the Canadian researchers showed that the ABCR transporter protein was also found in color sensing cells or cones (the macula zone of your retina only has cones) as well as the black and white sensing rods found in the
peripheral retina.
Your financial support can assist the MDF Gene Library Project that helps genetic researchers around the Nation recruit suitable family members to share their disease history and provide tissue samples to
accelerate this vital research. (See below)
Regeneration Edges One Step Closer to Reality
For us the most promising work presented at ARVO revolved around the possibility of waking up nests of sleeping neural stem
cells and putting them to work in the macula zone of the retina. Working independently, small groups of US and Chinese scientists reported injecting these cells into the space beneath rat retinas and stimulating them to grow into
macular light sensing cells or photoreceptors. For our full report on this important development click on the following link to our site: http://www.eyesight.org/Research/Regeneration/regeneration.html
What are the
implications of this research for patients with macular degeneration?
First, this work explodes the myth that macular degeneration is irreversible. As the MDF has long held, it clearly is not. These landmark studies
demonstrate that, in adult eyes, one can resurrect vision-related cells like photoreceptors and induce production of critical visual-process-dependent chemicals such as rhodopsin.
Second it emphasizes the critical importance
of more funding for omni-potent cell related research as the best hope yet for a cure for this disease. The MDF is redoubling its efforts to fund additional studies to broaden our understanding of these remarkable cells and develop
the best ways to accelerate application of this new knowledge for humans.
You can help us to help you or someone you love by contributing to the MDF Cells for Sight Initiative. Together we can help better fund the existing
small group of researchers, enabling them to accelerate their work and add new talent and resources to the development of human therapies based upon this exciting discovery.
Please send your tax deductible contribution to:
Macular Degeneration Foundation
P.O. Box 9752
San Jose, CA 95157
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2. NEW WEB SITE FEATURES
Slide Presentation
IRIDEX
Corporation, an innovative ophthalmologic laser company, has made a slide presentation available to the MD Foundation which is now showing our web site. It illustrates the structure of the diseased macula and describes how various
investigational therapies are believed to work.
Search Engine
We have made it easier for visitors to locate specific information. You may now enter key words and let the search engine do the work. A
link to the search engine (called SITE SEARCH) is available from the left-hand navigation bar on most pages.
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3. YOUR INPUT
As conditions like
Macular Degeneration slowly degrade a person's ability to see, people learn to compensate and lead otherwise normal lives. If you are coping with low vision and have found innovative ways of staying productive and
independent, please email your experience in 100 words or less to magnifier@eyesight.org and we will share selected suggestions in future editions of the MAGNIFIER.
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4. INTERNET HINTS
It can be a challenge and time consuming to locate specific information on a web page that contains lots of text. However, if you
know a key word, your browser contains a feature that makes life a little easier. To make use this feature, go to "Edit" on your browser's menu bar and click "Find". Enter a search word and the browser
will highlight that word where ever it appears on that page.
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Note: the above information does not constitute medical advice. Only your physician or licensed ophthalmologist
can dispense medical advice based upon a complete and thorough evaluation of your specific and unique situation.
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The MAGNIFIER is sent without charge. We hope that it will continue
to serve the interests of its subscribers. Contributions to the Macular Degeneration Foundation are appreciated and may be sent to P.O. Box 9752, San Jose, CA 95157
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