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Israeli researchers zero in on nearsightedness gene

The gene behind nearsightedness has been identified for the first time ever by an Israeli research group.
The team of researchers at Ben-Gurion University of the Negev found a mutation to of a gene called LEPREL1 that cause myopia (nearsightedness) in members of a Bedouin tribe living near the university in southern Israel.

Nearsightedness is the most common human eye disorder, and it can lead to a higher incidence of retinal detachment, macular degeneration and premature glaucoma and cataracts.
Leader of the research team, Prof. Ohad Birk of the National Institute for Biotechnology and the Dayan Clinical Genetics Wing at Soroka Medical Center says LEPREL1 encodes an enzyme essential for the final modification of collagen in the eye.

He explains that if a mutation in the gene harms the activity of this enzyme, the collagen is malformed and the eyeball will be longer than normal. As a consequence, light entering the eye gets focused in front of the retina rather than directly on the retina as it should be. That’s the definition of myopia.

 

Eyes are windows to medical records

Technology is on the rise that scans palm prints, eyes and voices to allow access into rooms or data and to verify identities. Based on biometrics, these systems recognize individuals by analyzing unique characteristics of a person’s body or behavior.

But with recent advances in the technology, new biometric systems are coming onto the scene, such as the full-body scanners used by the U.S. Department of Homeland Security announced. And as more scanning systems roll out, and through which citizens are linked to databases, privacy advocates stress the risks of having personal information in the open.

Other choices to identify patients biometrically are:

  • Photography;  but that was imprecise.
  • Fingerprints;  some patients associated that with the police and crime.
  • Palm readers: that required physical contact because that would easily spread germs.

Far from the sleek European airports, a South Bronx clinic that receives federal funding and operates in one of the most impoverished U.S. areas uses an iris scanning instrument to prevent medical record mishaps. The clinic formed a partnership with the company Eye Controls to develop a more user-friendly model, consisting of a handheld iris camera and software to reduce identification errors. Read the story here on CNN.

The iris, which is the colored ring of the eye, is unique for every human being. The company tested the iris scanner with simulated IDs and found zero errors in 8 million transactions. The abundance of detail in the iris, its variability and lack of genetic dependence, and its accessibility for imaging without physical contact all make the iris an excellent personal identifier.  Each of the three main biometrics has applications where it excels.  However, for patient identification, iris has the edge.  Iris recognition is more accurate than either fingerprints or facial, which is important where the standard is a zero error rate.

Welcome to the new world!

 

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Posted by on November 1, 2011 in Uncategorized

 

Optometrists Enjoy Impact Of Eye Care In People’s Lives.

In a piece exploring the benefits of a career as an optometrist, the Chicago Tribune reports, “An optometrist has one main goal, to help people see well. They test patients for eye diseases and vision problems and prescribe glasses, contacts or other treatments, like vision therapy.”

The article follows Chicago optometrists Robert Steinmetz, OD, and Matthew Gifford, MD. “Both Steinmetz and Gifford love the immediacy of the impact they have on people’s lives through eye care. Unlike other doctors, optometrists do not need to wait to see the effect of medication, which might take months to resolve a problem, Steinmetz says.”

Gifford advises would-be optometrists to research “the business side of the job, so that when they graduate school, they will be able to open their own business.”

 
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Posted by on November 1, 2011 in Uncategorized

 

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Pinkeye Treatment Coming Soon?

Pink eye, or conjunctivitis, is redness and inflammation of the membranes (conjunctiva) covering the whites of the eyes and the membranes on the inner part of the eyelids. These membranes react to a wide range of bacteria, viruses, allergy provoking agents, irritants, and toxic agents, as well as to underlying diseases within the body.

Viral and bacterial forms of conjunctivitis are common in childhood, but they occur in adults as well. There are no recommended antiviral drugs to treat a highly contagious form of viral conjunctivitis called pinkeye.

Outbreaks result in millions of lost school and workdays each year in the U.S. as patients stay home to avoid infecting others while the condition improves.

Now early research from Sweden suggests that an experimental eye drop might stop viral pinkeye in its tracks and keep family members, schoolmates, coworkers, and other close contacts of patients from becoming infected.

The drops have not been studied in humans, but researchers state they are optimistic the treatment will prevent infection by tricking the virus into binding to artificial surfaces in the drops designed to mimic key cells in the eye.

Once this happens, the entrapped virus should be easily washed from the eye in tears, states researcher Ulf Ellervik, PhD, who is a professor of microbiology at Sweden’s Umea University.

“Pinkeye is a very troublesome condition,” Ellervik says. “If one family member gets it, usually everyone gets it.”

The experimental treatment targets adenoviruses 8, 19, and 37, which cause most viral conjunctivitis.

 
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Posted by on October 3, 2011 in Uncategorized

 

FDA Grants Orphan Drug Status For Keratoconus Treatment

Keratoconus is a degenerative disease of the eye that is characterized by progressive thinning of the cornea and represents the leading cause of corneal transplants in the United States. It affects 1 in every 2000 Americans.

The US Food and Drug Administration (FDA) has granted orphan drug status to a 0.1% riboflavin ophthalmic solution (VibeX) combined with an ultraviolet A (UVA) irradiation system (KXL, Avedro, Inc) to perform corneal cross-linking in the treatment of keratoconus.

The action was based on clinical data from 3 US multicenter phase 3 studies.

Corneal collagen cross-linking using UVA light with riboflavin photosensitizer is the first medical therapy available in the United States to control the progression of keratoconus. Most treatments to date have focused on using contact lenses or glasses to mitigate the refractive error induced by progressive thinning and bulging of the cornea. Other options have included corneal implants and corneal transplantation.

The new treatment works by strengthening the cross-links between fibrils that serve as “natural anchors” within the cornea, thereby reducing the abnormal curvature associated with keratoconus.

Widely used in Europe and Asia over the past 12 years, the procedure is being performed in approximately 450 centers worldwide.

“Avedro’s effort to make this clinically important treatment available to US patients will be applauded by all US ophthalmologists who today lack any approved therapeutic treatment to halt the progression of keratoconus,” said Peter S. Hersh, MD, refractive surgeon and medical monitor for Avedro’s clinical trials, in a company news release.

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Posted by on September 15, 2011 in Uncategorized

 

Another approach to address Dry Eye

Dry eye disease is one of the most common ophthalmic problems, with an estimated 30 million people in North-America suffering from it and a worldwide prevalence closely paralleling that of the United States. Dry eye is a chronic multifactorial disease of the tears, the ocular surface and the adjacent neurological tissue that results in symptoms of discomfort, visual disturbance and tear film instability that may lead to permanent damage and scars to the ocular surface.

A Canadian company Mimetogen Pharmaceuticals Inc. (“Mimetogen”) today announced positive top line data from a Phase II clinical trial with MIM-D3, its lead drug for the treatment of dry eye. The trial demonstrated statistically significant improvements in signs and symptoms with its doses of MIM-D3. Mimetogen is in the process of completing its analysis of the data, and intends to present further details at a future medical conference.

The 150-patient phase II study utilized a controlled adverse environment (CAETM) chamber to measure dry eye patients’ ability to withstand a stressful drying environment on the eye, and patient diaries to measure the severity of their dry eye symptoms over the course of the study. Patients were randomized to receive MIM-D3 low dose, MIM-D3 high dose or placebo twice/day over the course of a 28-day study.

Mimetogen’s lead drug candidate for the treatment of dry eye disease, MIM-D3, is a small molecule mimetic of nerve growth factor (NGF). NGF is a naturally occurring protein in the eyes that is responsible for the maintenance of corneal nerves and epithelium, mucin and tear production. In contrast to most other products in development or on the market, MIM-D3 is designed to quickly and directly improve the quality of the tears produced by the eyes whilst reducing clinical signs and symptoms such as chronic dryness and grittiness. Dry eye disease is estimated to be a $1 billion US market for which there is currently only one FDA-approved treatment.

The Phase II randomized, double-masked, multi-center, placebo-controlled trial was designed to evaluate the safety, tolerability and efficacy of MIM-D3 in improving both the signs and symptoms of dry eye.

 

 
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Posted by on September 15, 2011 in Uncategorized

 

Magnets to Treat Diabetic Retinopathy

Diabetic retinopathy is caused by damage to blood vessels of the retina. The retina is the layer of tissue at the back of the inner eye. It changes light and images that enter the eye into nerve signals that are sent to the brain.

There are two types, or stages of diabetic retinopathy:

  • Nonproliferative develops first
  • Proliferative is the more advanced and severe form of the disease

Diabetic retinopathy is the leading cause of blindness in working-age Americans. People with type 1 diabetes and type 2 diabetes are at risk for this condition.

Having more severe diabetes for a longer period of time increases the chance of getting retinopathy. Retinopathy is also more likely to occur earlier and be more severe if your diabetes has been poorly controlled.

Researchers at the University of British Columbia  have developed a novel device that will make drug treatment for diabetic retinopathy safer and more effective. The device, smaller than the head of a pin, consists of a sealed reservoir made of flexible polydimethylsiloxane (now say that quickly 3 times) that is implanted behind the eye. Part of the reservoir’s flexible membrane is magnetic; an electric field applied to the device causes the magnetic membrane to deform and release a controlled amount of drug out of a small hole, much in the same way water is released from a plastic bottle when it’s squeezed.

The novel drug delivery mechanism is detailed in the current issue of Lab on a Chip, a multidisciplinary journal on innovative microfluidic and nanofluidic technologies.

The lead authors are recent PhD mechanical engineering graduate Fatemeh Nazly Pirmoradi, who completed the study for her doctoral thesis, and Mechanical Engineering Assoc. Prof. Mu Chiao, who studies nanoscience and microelectromechanical systems for biological applications.

Pirmoradi says it will be several years before the UBC device is ready for patient use. “There’s a lot of work ahead of us in terms of biocompatibility and performance optimization.”

The team is also working to pinpoint all the possible medical applications for their device so that they can tailor the mechanical design to particular diseases.

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Posted by on September 14, 2011 in Uncategorized

 

Video Games Improve ‘Lazy Eye’ in Adults

Amblyopia is a brain disorder in which vision in one eye does not develop properly. It is the most common cause of permanent visual impairment in childhood, affecting 2 to 3 out of every 100 American children, according to the National Eye Institute. Amblyopia is also the most common cause of one-eye visual impairment among young and middle-age adults.

While amblyopia in children can be successfully treated through occlusion therapy – putting a patch over the “good eye” to force the brain to use the weaker “lazy eye” – few options are available for adults with this condition.

“These new findings are very encouraging because there are currently no accepted treatments for adults with amblyopia,” said study principal investigator Dr. Dennis Levi, UC Berkeley professor and dean of optometry and a researcher at the Helen Wills Neuroscience Institute. “A lot of eye doctors start closing the books on successful treatment after age 8 or so because of the widespread belief that amblyopia can only be reversed during a critical window of development in the visual cortex. If the disorder is not corrected in childhood, the damage was thought to be irreversible.”

But recent studies on perceptual learning, including those authored by Levi and Li, have dispelled the notion that no vision improvements are possible in adult amblyopes. They found that intensive training on a perceptual task, such as getting two horizontal lines aligned, could lead to a 30-40 percent improvement in visual acuity.

In the first experiment, 10 participants played the action video game for a total of 40 hours, two hours at a time, over the course of a month. In a second experiment, three other participants played the non-action video game for the same amount of time. While they were playing video games, participants wore a patch over their good eye.

Both experiments yielded a 30 percent increase in visual acuity, or an average improvement of 1.5 lines on the standard letter chart used by optometrists. In comparison, it can take 120 hours of occlusion therapy to see a one-line improvement on the letter chart in children with amblyopia, the authors said.

Performance was measured after every 10 hours of gaming, the researchers noted, and some subjects started improving earlier than 40 hours.

To verify that the results were specific to video game playing and not due to the use of the eye patch, the researchers conducted a third experiment in which seven participants wore a patch over their good eye for 20 hours during their normal daily activities, such as watching television, reading books and surfing the Internet. At the end of the 20 hours, they showed no improvement on the vision tests. Those same subjects were then asked to wear a patch while playing video games for 40 hours, and when tested, showed the same level of improvement as the other study participants.

Among the 20 study participants, half had strabismic amblyopia, marked by misaligned or crossed eyes. Six had anisometropic amblyopia, in which the two eyes have significantly different prescriptions. Another three had both conditions, and one subject had amblyopia caused by cataracts in one eye.

The study found no significant difference in visual acuity improvement among the different types of amblyopia. However, anisometropic subjects also saw a 50 percent improvement in 3-D depth perception after 40 hours of playing video games.

Li noted that the subjects who started off playing a non-action video game continued to improve after playing the action video game for an additional 40 hours. “It is not clear, yet, when vision improvement might plateau,” he said. “But it’s likely that those who have severe amblyopia will take longer to show improvement, but those patients also have the most room for improvement.”

Li also cautioned that the research on video game therapy for amblyopia is still in its early stages, and that patients should not attempt to “self-treat” their amblyopia. “People definitely need to work with their eye doctors,” he said.

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Posted by on September 12, 2011 in Uncategorized

 

FDA Delays Approval Decision On Eylea

Regeneron Pharmaceuticals announced yesterday that US regulators delayed a decision on whether to approve the company’s treatment for wet age-related macular degeneration (AMD), saying that the Food and Drug Administration extended its target date to complete its review of the medicine by three months to Nov. 18.

 

 

Regeneron Pharmaceuticals Inc. (REGN) declined as much as 13 percent in extended trading after U.S. regulators announced this decision. The drug, known as Eylea, would compete with Lucentis from Basel, Switzerland-based Roche Holding AG. (ROG).

EYLEA is a fully human fusion protein, consisting of portions of VEGF receptors 1 and 2, that binds all forms of VEGF-A along with the related Placental Growth Factor (PlGF).  EYLEA is a specific and highly potent blocker of these growth factors.  EYLEA is specially purified and contains iso-osmotic buffer concentrations, allowing for injection into the eye.

Regeneron and Bayer HealthCare are collaborating on the global development of EYLEA for the treatment of wet AMD, central retinal vein occlusion (CRVO), diabetic macular edema (DME), and myopic choroidal neovascularization (mCNV).

Eylea is injected every eight weeks, half as often as Lucentis. The less frequent dosing would help Regeneron capture 25 percent of the U.S. market from Lucentis, Edward Tenthoff, a senior research analyst with Piper Jaffray & Co. in NY, said yesterday in a note to investors.

Approval for Eylea in other countries outside of US were based on positive results from two Phase 3 trials, the VIEW 1 study conducted in North America and the VIEW 2 study conducted in Japan, Europe, and other countries.  In these trials, all regimens of EYLEA, including 2 milligrams (mg) dosed every two months (following three initial monthly doses), successfully met the primary endpoint of statistical non-inferiority compared to the current standard of care, ranibizumab 0.5 mg dosed every month, in the proportion of patients who maintained (or improved) vision over 52 weeks.  A generally favorable safety profile was observed for both EYLEA and ranibizumab. The most frequent ocular adverse events were conjunctival hemorrhage, macular degeneration, eye pain, retinal hemorrhage, and vitreous floaters, which were balanced across all treatment groups in both studies.  There were no notable differences in non-ocular adverse events among the study arms.

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Posted by on August 17, 2011 in Uncategorized

 

Retinal Photographs May Help Diagnose Alzheimer’s

PET scan of a normal human brain

Image via Wikipedia

Investigators claim to have discovered a possible way of detecting Alzheimer’s disease by examining retinal photographs to ascertain the width of certain blood vessels. This data was presented Sunday at the Alzheimer’s Association International Conference on Alzheimer’s Disease.

Among the possible advances in early detection are chemical tracers, some of which tag clumps of a sticky substance in the brain called amyloid, and others that mark amyloid and a protein called tau—both thought to contribute to the disease.

These tracers make Alzheimer’s pathology visible in a living brain, which until now could only be seen upon autopsy. The new findings show the presence of amyloid on a PET scan might lead to greater memory loss or other cognitive troubles.

In the study, researchers examined 31 Alzheimer’s patients, 51 with mild cognitive impairment and 69 said to be healthy, using Eli Lilly & Co.’s florbetapir, one of several tracers under development, with a PET scan. They found that patients who had more amyloid in the brain on the PET scan exhibited a steeper decline in cognitive symptoms than people who had none over an 18-month period.

Another study presented Sunday examined the potential of identifying characteristics of the eye as a quick and noninvasive way of detecting the disease. Because the eye is closely linked to the brain, some Alzheimer’s pathology also affects the eye.

In a preliminary study, Australian researchers examined the photographs of the light-sensitive part of the eye called the retina in 13 people with Alzheimer’s, 13 with mild cognitive impairment and 110 healthy individuals. They found that the width of some blood vessels in the retina of people with Alzheimer’s was greater than in those who were healthy, according to study author Shaun Frost, of Australia’s national science agency, CSIRO. This was also was linked to the presence of amyloid plaques in the brain as measured by a PET scan, he said.

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Posted by on July 18, 2011 in Uncategorized

 
 
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