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Manufacturers' Corner: New Technology
MANUFACTURERS' CORNER: NEW TECHNOLOGY University of Florida researchers prove that arrestin moves inside rods
U
niversity of Florida researchers have obtained the first photographic proof that arrestin, a pro tein crucial to vision, moves inside rods in response to light. Arrestin regulates a chemical reaction responsi ble for vision that begins in the retina. To trace arrestin' s movements in rods, researchers introduced a gene derived from luminous jellyfish into African clawed frog tadpoles. The tadpoles' eyes produced arrestin that glowed bright green when exposed to blue light, making the protein easy to observe and, for the first time, photograph. In low-light conditions arrestin is stored in the inner segment. But in the pres ence of bright light, arrestin moves to the opposite end of the rod, the outer segment, where incoming light is captured. The researchers are particularly interested in targeting proteins involved in directing arrestin to the correct destinations in retinal cells. Defects in those proteins may cause problems in the movement, or translocation, of arrestin and may play a role in some retinal disorders, such as some forms of macular degeneration.
New study highlights role of placental growth factor in angiogenesis
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study by Peter Carmeliet and colleagues (University of Leuven, Belgium) that recently appeared in Nature Medicine provides compelling evidence of the distinct role of placental growth factor (PlGF) in stimulating new blood vessel formation. Professor Carmeliet's laboratory previously reported that PlGF amplifies vascular endothelial growth factor (VEGF)-driven angiogenesis under ischemic condi tions. Unlike VEGF, which binds to both Flkl and Fltl receptors, PlGF binds only to Fltl receptors, leading to a very different and independent effect in terms of both receptor activation and subsequent gene activation. Furthermore, PlGF has been shown to amplify the angiogenic effect of VEGF, thereby tar geting its effect only at sites of hypoxia (where endogenous VEGF is upregulated). VEGF has shown promise in the treatment of ischemic conditions, but its therapeutic potential is hampered by dose-limiting side effects. PlGF, owing to its more specific activity and targeted angiogenic effect at the site of ischemia,
may allow for an improved risk-benefit ratio in the treatment of ischemic conditions, such as ischemic heart disease and peripheral arterial occlusive disease. Anecortave acetate demonstrates significant long-term efficacy in wet age-related macular degeneration
A
Icon, Inc. has reported that long-term use of its investigational new drug, Retaane (anecortave acetate for depot suspension), preserves vision, pre vents severe vision loss and inhibits lesion growth in patients with wet age-related macular degeneration. Data from a 24-month phase II/III study add to and confirm the previously reported 12-month findings, which showed that a 15-mg treatment of Retaane has the potential to safely and effectively preserve sight in patients with this disorder. Retaane works by slowing or stopping the growth of new blood vessels, which leads to less leakage and less retinal damage. Patients received Retaane or placebo every 6 months during an in-office procedure in which the suspension was placed onto the outer surface of the back of the eye directly behind the macula. This method of delivery allows the drug to diffuse across the sclera and choroid into the macula over 6 months. Alcon has launched a phase III trial of the drug involving about 500 patients at more than 50 sites in the United States, Canada, Europe and Australia. University of Florida wound-healing experts host symposium to share new methods of fighting harmful scarring
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ew technologies to prevent harmful scars using genetics, growth-blocking drugs and artificial skin were showcased recently at a symposium entitled "Breakthroughs in Ocular and Non-Ocular Wound Healing" sponsored by the University of Florida's Center for Vision Research. As a result of the sympo sium, two new collaborations have been formed between researchers at the University and at other institutions. One project will focus on sophisticated three-dimensional imaging to investigate possible treatments for scarring in epithelial cells. In the sec ond project, researchers will develop an instrument to measure the amount of corneal haze in patients with vision problems.
CAN J OPHTHALMOL-VOL. 38, NO. 7, 2003
621
U
niversity of Florida researchers have obtained the first photographic proof that arrestin, a pro tein crucial to vision, moves inside rods in response to light. Arrestin regulates a chemical reaction responsi ble for vision that begins in the retina. To trace arrestin' s movements in rods, researchers introduced a gene derived from luminous jellyfish into African clawed frog tadpoles. The tadpoles' eyes produced arrestin that glowed bright green when exposed to blue light, making the protein easy to observe and, for the first time, photograph. In low-light conditions arrestin is stored in the inner segment. But in the pres ence of bright light, arrestin moves to the opposite end of the rod, the outer segment, where incoming light is captured. The researchers are particularly interested in targeting proteins involved in directing arrestin to the correct destinations in retinal cells. Defects in those proteins may cause problems in the movement, or translocation, of arrestin and may play a role in some retinal disorders, such as some forms of macular degeneration.
New study highlights role of placental growth factor in angiogenesis
A
study by Peter Carmeliet and colleagues (University of Leuven, Belgium) that recently appeared in Nature Medicine provides compelling evidence of the distinct role of placental growth factor (PlGF) in stimulating new blood vessel formation. Professor Carmeliet's laboratory previously reported that PlGF amplifies vascular endothelial growth factor (VEGF)-driven angiogenesis under ischemic condi tions. Unlike VEGF, which binds to both Flkl and Fltl receptors, PlGF binds only to Fltl receptors, leading to a very different and independent effect in terms of both receptor activation and subsequent gene activation. Furthermore, PlGF has been shown to amplify the angiogenic effect of VEGF, thereby tar geting its effect only at sites of hypoxia (where endogenous VEGF is upregulated). VEGF has shown promise in the treatment of ischemic conditions, but its therapeutic potential is hampered by dose-limiting side effects. PlGF, owing to its more specific activity and targeted angiogenic effect at the site of ischemia,
may allow for an improved risk-benefit ratio in the treatment of ischemic conditions, such as ischemic heart disease and peripheral arterial occlusive disease. Anecortave acetate demonstrates significant long-term efficacy in wet age-related macular degeneration
A
Icon, Inc. has reported that long-term use of its investigational new drug, Retaane (anecortave acetate for depot suspension), preserves vision, pre vents severe vision loss and inhibits lesion growth in patients with wet age-related macular degeneration. Data from a 24-month phase II/III study add to and confirm the previously reported 12-month findings, which showed that a 15-mg treatment of Retaane has the potential to safely and effectively preserve sight in patients with this disorder. Retaane works by slowing or stopping the growth of new blood vessels, which leads to less leakage and less retinal damage. Patients received Retaane or placebo every 6 months during an in-office procedure in which the suspension was placed onto the outer surface of the back of the eye directly behind the macula. This method of delivery allows the drug to diffuse across the sclera and choroid into the macula over 6 months. Alcon has launched a phase III trial of the drug involving about 500 patients at more than 50 sites in the United States, Canada, Europe and Australia. University of Florida wound-healing experts host symposium to share new methods of fighting harmful scarring
N
ew technologies to prevent harmful scars using genetics, growth-blocking drugs and artificial skin were showcased recently at a symposium entitled "Breakthroughs in Ocular and Non-Ocular Wound Healing" sponsored by the University of Florida's Center for Vision Research. As a result of the sympo sium, two new collaborations have been formed between researchers at the University and at other institutions. One project will focus on sophisticated three-dimensional imaging to investigate possible treatments for scarring in epithelial cells. In the sec ond project, researchers will develop an instrument to measure the amount of corneal haze in patients with vision problems.
CAN J OPHTHALMOL-VOL. 38, NO. 7, 2003
621