From the Los Angeles Time, Dec 29'2010
Nintendo's 3DS video game system might be hazardous to the health of children younger than 6, according to a warning posted Wednesday on the Japanese video game company's website.
"Vision of children under the age of 6 [is in] the developmental stage," Nintendo's warning said, according to a Google translation of the website. "Nintendo 3DS, 3-D, including 3-D movies and television, delivers 3-D images with different left and right eye images," which "has a potential impact on the growth of children's eyes."
The 3DS is the gaming giant's latest version of its DS line of handheld video game consoles. The feature of the 3DS that separates it from Nintendo's popular other DS systems: It can handle 3-D gaming and movies, displaying the depth-adding effect without requiring users to wear 3-D glasses.
Although Nintendo is advising that only the preschool crowd refrain from using the new system's 3-D feature, it also recommends in its note that all players -- children and adults -- should take breaks from its glasses-free 3-D gaming every 30 minutes, or whenever a user feels sick.
The 3DS will also have a "3-D volume" sliding button that will let users tone down the level of depth of 3-D images, the notice said
It also said the 3DS would have a parental control feature that could restrict the console's screens to traditional 2-D images. Games, movies and other media displayed in 2-D will be safe for gamers younger than 6, the Nintendo warning said.
There is "enough for everyone to enjoy," it said.
Nintendo is set to release the 3DS in Japan on Feb. 26 for about $300. The 3DS is to arrive in U.S. stores in March, the company has said; a price hasn't yet been announced.
The 3DS isn't Nintendo's first try at 3-D video games. In 1995 the company released the Virtual Boy, which had two LED screens that displayed black and red 3-D effects in a viewfinder-like device.
The Virtual Boy didn't catch on. It was discontinued in 1996 and is one of Nintendo's few console failures.
Thursday, December 30, 2010
Friday, December 24, 2010
Canadian breakthrough in cataract treatment
Tuesday, Dec 21, 2010
The Canadian company Vision Rejuvenation™ Victoria (British Columbia) has become the first centre in Canada to implant the world’s first light adjustable intraocular lens.
The Calhoun Vision LAL® lens was implanted by Dr. Lawrence Brierley, surgeon and medical director at Vision Rejuvenation. Dr. Brierley is involved in a clinical study through Health Canada to determine the safety and effectiveness of the lens and the light delivery device.
The main problem with cataract surgery is that it is difficult to precisely determine in advance what lens power the patient needs. The patient has to live with the visual problems resulting from any errors or undergo further surgical procedures. The light adjustable lens is the solution to this problem. Once the eye has healed after surgery, the patient’s ability to see near and far is assessed and a light source is applied to change the shape of the lens.
“This breakthrough technology is one of the greatest advances in cataract surgery in years. I have been waiting all my life for the sort of precision that this lens allows me,” says Dr. Brierley. “It is like having an insurance policy that ensures accurate and precise outcomes based on specific patient requirements.”
The Canadian company Vision Rejuvenation™ Victoria (British Columbia) has become the first centre in Canada to implant the world’s first light adjustable intraocular lens.
The Calhoun Vision LAL® lens was implanted by Dr. Lawrence Brierley, surgeon and medical director at Vision Rejuvenation. Dr. Brierley is involved in a clinical study through Health Canada to determine the safety and effectiveness of the lens and the light delivery device.
The main problem with cataract surgery is that it is difficult to precisely determine in advance what lens power the patient needs. The patient has to live with the visual problems resulting from any errors or undergo further surgical procedures. The light adjustable lens is the solution to this problem. Once the eye has healed after surgery, the patient’s ability to see near and far is assessed and a light source is applied to change the shape of the lens.
“This breakthrough technology is one of the greatest advances in cataract surgery in years. I have been waiting all my life for the sort of precision that this lens allows me,” says Dr. Brierley. “It is like having an insurance policy that ensures accurate and precise outcomes based on specific patient requirements.”
Friday, December 17, 2010
Scientists May Have Partially Reversed Age-Related Degeneration In Mice.
SUNDAY, Nov. 28 (HealthDay News) -- U.S. scientists say they have partially reversed age-related degeneration in mice, leading to new brain and testes growth, improved fertility and the return of lost cognitive function, or thinking skills.
The advance in aging science was achieved by working with telomerase genes in the mice, said the team at the Dana-Farber Cancer Institute in Boston.
The researchers developed mice with a controllable telomerase gene. (Telomerase is an enzyme that helps maintain telomeres -- the protective "caps" on the ends of chromosomes.) As people age, low levels of telomerase lead to progressive erosion and shortening of the telomeres, resulting in physical and mental decline, the study authors explained in a news release from the institute.
Creating mice with a controllable telomerase switch enabled the scientists to create prematurely aged mice. The switch also enabled the team to determine that reactivating telomerase in the mice could restore telomeres and reduce the signs and symptoms of aging.
In addition, the mice did not show signs of cancer -- a key concern because cancer cells can use telomerase to make themselves virtually immortal. Researchers noted that this is an important area of study for future investigation.
In the future, it may be possible to use this approach to treat people with conditions such as rare genetic premature aging syndromes, in which shortened telomeres play an important role, said study senior author Dr. Ronald A. DePinho, director of Dana-Farber's Belfer Institute of Applied Cancer Science.
"Whether this would impact on normal aging is a more difficult question," he said in the news release. "But it is notable that telomere loss is associated with age-associated disorders and thus restoration of telomeres could alleviate such decline."
DePinho also said the study may lead to new directions for regenerative medicine because the findings suggest that dormant adult stem cells in extremely aged tissues remain viable and can be reactivated to repair tissue damage.
"If you can remove the underlying damage and stresses that drive the aging process and cause stem cells to go into growth arrest, you may be able to recruit them back into a regenerative response to rejuvenate tissues and maintain health in the aged," he said in the release.
The study was released online in advance of publication in an upcoming print issue of the journal Nature.
The advance in aging science was achieved by working with telomerase genes in the mice, said the team at the Dana-Farber Cancer Institute in Boston.
The researchers developed mice with a controllable telomerase gene. (Telomerase is an enzyme that helps maintain telomeres -- the protective "caps" on the ends of chromosomes.) As people age, low levels of telomerase lead to progressive erosion and shortening of the telomeres, resulting in physical and mental decline, the study authors explained in a news release from the institute.
Creating mice with a controllable telomerase switch enabled the scientists to create prematurely aged mice. The switch also enabled the team to determine that reactivating telomerase in the mice could restore telomeres and reduce the signs and symptoms of aging.
In addition, the mice did not show signs of cancer -- a key concern because cancer cells can use telomerase to make themselves virtually immortal. Researchers noted that this is an important area of study for future investigation.
In the future, it may be possible to use this approach to treat people with conditions such as rare genetic premature aging syndromes, in which shortened telomeres play an important role, said study senior author Dr. Ronald A. DePinho, director of Dana-Farber's Belfer Institute of Applied Cancer Science.
"Whether this would impact on normal aging is a more difficult question," he said in the news release. "But it is notable that telomere loss is associated with age-associated disorders and thus restoration of telomeres could alleviate such decline."
DePinho also said the study may lead to new directions for regenerative medicine because the findings suggest that dormant adult stem cells in extremely aged tissues remain viable and can be reactivated to repair tissue damage.
"If you can remove the underlying damage and stresses that drive the aging process and cause stem cells to go into growth arrest, you may be able to recruit them back into a regenerative response to rejuvenate tissues and maintain health in the aged," he said in the release.
The study was released online in advance of publication in an upcoming print issue of the journal Nature.
Vodka eyeball shots a dangerous way to imbibe
By Elizabeth Weise, USA TODAY
College students have long done crazy things, from swallowing gold fish to jamming themselves into telephone booths. Not all things they try are dangerous, but some are.
Two new cases in point: consumption of controversial alcoholic energy drinks likely to be banned today; and a bizarre method of trying to get plastered by absorbing alcohol through the eyeball.
The eyeball shots don't succeed and definitely fall in the category of risky behaviors, experts say.
"This is an activity that has no upside to it," says David Granet, a professor of ophthalmology at the University of California, San Diego.
The theory among the students seems to be that alcohol can be absorbed through mucous membranes, and the eyeball and inner side of the eyelids are covered in mucous membrane, so, voila!— vodka eyeball shots. There are more than 30 homemade videos of young men doing this on YouTube.
Not only does it fail to get someone drunk, "it hurts and it will cause permanent damage to the surface of the eye," Granet says.
Ophthalmologists have been speaking out against this trend ever since it appeared on U.S. campuses last spring. According to the American Academy of Ophthalmology, it appears to have begun in England.
"There is absolutely, positively nothing that can be construed as fun about this," Granet says.
These kinds of stunts are "a normal reflection of this developmental stage," says Paul Lyons, a professor of community medicine at Temple University School of Medicine in Philadelphia. Drinking pranks are really just experimentation by young adults who are not at full adult decision-making capacity, he says.
Another generally ineffectual means of becoming inebriated is the use of vodka-soaked tampons for both women and men (used as suppositories for males). No videos of this were found on YouTube.
Other less popular, but still Internet-flogged methods, include putting vodka in an asthma atomizer so it can be inhaled (no videos found) and snorting it (more than 300 videos).
What has changed is that the Internet now allows stupid behaviors to be amplified in ways they couldn't easily be before, Lyons says. For example, there's no epidemic of students punching themselves in the face, but there are more than 20 videos of youths doing so online.
Online sources such as Facebook and YouTube can distort social norms.
Research has shown that students overestimate how much their peers are drinking, says Laura Talbott, professor of health education at the University of Alabama-Birmingham.
College and university administrations are working hard to create peer programs to counteract the attention such social media can give to rare and destructive behaviors, says Talbott, who chairs the American College Health Association's Alcohol and Other Drug Coalition.
As the Internet amplifies what might otherwise be a stunt by a few students, marketers are entering the scene, says Peter Lake, a professor of higher education law at Stetson University law school in Gulfport, Fla.
"There are industries now that try to make money on this. They realize this is a susceptible group and they can market to it with products that more mature individuals wouldn't choose," he says.
College students have long done crazy things, from swallowing gold fish to jamming themselves into telephone booths. Not all things they try are dangerous, but some are.
Two new cases in point: consumption of controversial alcoholic energy drinks likely to be banned today; and a bizarre method of trying to get plastered by absorbing alcohol through the eyeball.
The eyeball shots don't succeed and definitely fall in the category of risky behaviors, experts say.
"This is an activity that has no upside to it," says David Granet, a professor of ophthalmology at the University of California, San Diego.
The theory among the students seems to be that alcohol can be absorbed through mucous membranes, and the eyeball and inner side of the eyelids are covered in mucous membrane, so, voila!— vodka eyeball shots. There are more than 30 homemade videos of young men doing this on YouTube.
Not only does it fail to get someone drunk, "it hurts and it will cause permanent damage to the surface of the eye," Granet says.
Ophthalmologists have been speaking out against this trend ever since it appeared on U.S. campuses last spring. According to the American Academy of Ophthalmology, it appears to have begun in England.
"There is absolutely, positively nothing that can be construed as fun about this," Granet says.
These kinds of stunts are "a normal reflection of this developmental stage," says Paul Lyons, a professor of community medicine at Temple University School of Medicine in Philadelphia. Drinking pranks are really just experimentation by young adults who are not at full adult decision-making capacity, he says.
Another generally ineffectual means of becoming inebriated is the use of vodka-soaked tampons for both women and men (used as suppositories for males). No videos of this were found on YouTube.
Other less popular, but still Internet-flogged methods, include putting vodka in an asthma atomizer so it can be inhaled (no videos found) and snorting it (more than 300 videos).
What has changed is that the Internet now allows stupid behaviors to be amplified in ways they couldn't easily be before, Lyons says. For example, there's no epidemic of students punching themselves in the face, but there are more than 20 videos of youths doing so online.
Online sources such as Facebook and YouTube can distort social norms.
Research has shown that students overestimate how much their peers are drinking, says Laura Talbott, professor of health education at the University of Alabama-Birmingham.
College and university administrations are working hard to create peer programs to counteract the attention such social media can give to rare and destructive behaviors, says Talbott, who chairs the American College Health Association's Alcohol and Other Drug Coalition.
As the Internet amplifies what might otherwise be a stunt by a few students, marketers are entering the scene, says Peter Lake, a professor of higher education law at Stetson University law school in Gulfport, Fla.
"There are industries now that try to make money on this. They realize this is a susceptible group and they can market to it with products that more mature individuals wouldn't choose," he says.
Thursday, December 9, 2010
Great-Grandmother Says She Has Some Eyesight Back After Undergoing Stem-Cell Treatment In China.
By Daily Mail Reporter
Last updated at 12:22 AM on 2nd November 2010
'When I got back to Heathrow Airport last Wednesday I could see such a lot. It was unbelievable,' said Dorothy.
'The other day I saw a crow on the fence in my garden and had to check with people that I could actually see it but I did see it. It is amazing.
'The doctors said it could take another six months to a year before my sight gets as good as it will be, but it is much better already. It was definitely worth it.'
Dorothy's plight began when she woke up one morning in February last year to discover she had gone blind.
She was diagnosed with giant cell arteritis, an inflammatory disease of blood vessels.
Doctors in the UK said they could not restore her sight, but the Chinese hospital said it offered pioneering stem cell treatment that could restore her vision.
Stem cells are the very early cells that can develop into almost all other types of cell and tissue.
Dorothy went through a course of daily wave therapy and acupuncture, with weekly stem cell injections, for 43 days before arriving back home to her husband Percival in Springfield, Hardwicke.
Dorothy's main aim is to see her two-year-old great grandson Chris this Christmas.
The mother-of-four, grandmother-of-seven and great-grandmother of two, said: 'I really looking forward to being able to see Chris.
'As soon as his parents can get here to visit I am hoping to see him. They live on the army camp so it might be a little while, but I'm keeping my fingers crossed.'
Well wishers had organised parachute jumps, bingo evenings and fun days to raise the money to send Dorothy on her trip.
Dorothy added: 'I am so pleased that everyone helped to raise this money. It is so wonderful that everybody did it for me. I really couldn't have done it without them.'
Her daughter Vicky, who kept a blog on the experience, said she and her mother went to Qingdao Hospital where her treatment was overseen by Dr Tony Lao.
'The main treatment was a weekly injection of stem cell fluid taken from umbilical cords at a maternity centre in Beijing and flown to Qingdao,' she said.
'Mum had to have two injections of the fluid into her right eye without anaesthetic, one of which was very painful. There were also six injections of fluid into her hand.
'Every day she had wave therapy, which involves electrical impulses to stimulate the parts of the brain involved. And she had acupuncture every day with one needle in the top of her head, two in her wrists, two in her knees and two in her ankles.
'The hospital has become known throughout the world for this treatment that it has been performing since 2004. We met other patients there who had flown in from Brazil, Canada and America for it.
'Mum has good days and bad days with her sight now. She can see shapes and bright lights and on some days much more than that. One day when we were out there she was able to see the writing on a sign quite clearly.
'The doctor said she should hopefully get steadily better over the next six to 12 months. After a year her sight will probably be as good as it's going to get.'
Monday, December 6, 2010
The cheap reading glasses that can damage your sight
By Sean Poulter
Last updated at 1:08 AM on 31st October 2010
They may save you money in the short term but cheap reading glasses could end up costing your eyesight.
The so-called ‘ready readers’, which sell for as little as £1 in high street shops, may leave wearers with eye strain, headaches or even blurred or double vision.
Millions have bought them after baulking at the high cost of buying glasses from an optician.
However, research suggests they could be putting their eyesight and health at risk.
By the age of 50, most adults have problems reading a book or newspaper without spectacles.
So the arrival of the cheap glasses in supermarkets, high street stores and market stalls less than ten years ago has been seen as a saviour for many
A consumer might have to pay more than £100 for a pair of reading glasses from an optician, which might easily be lost or broken.
Instead, many buy several cheap versions to stash around the house so that they can always find a pair.
A researcher at consumer champion Which? checked 14 pairs from seven high street chains.
He found problems with half of them, with those carrying a higher prescription – +3.5 to +4 – considered to cause the most concern. ‘Off-the-peg glasses could cause eye strain, blurred vision, headaches or double vision,’ the Which? researcher said.
‘For people with higher prescriptions, they’re not suitable for walking or other mobile activities.’
They could even ‘cause a nasty accident’, he warned.
The biggest problem is that the centre point of the two lenses might not be aligned.
This means the sight in one eye might be clear while the other is blurred. This was the case in a pair from Poundland – which also had a prescription strength that differed from the +3.5 on the pack – and a £16 pair from fashion eyewear store Sight Station.
‘This could cause eye problems or a head tilt,’ the researcher said.
A £4 pair from Tiger were ‘unwearable’ because the centre point of the lenses did not match, while a £2 pair from Primark had ‘a very large difference’.
A £15 pair from Marks & Spencer were so ‘poorly made’ that the lenses were likely to drop out.
Which? advises people who have a prescription above +2 to test reading glasses for two minutes to check the centre points of each lens are aligned correctly.
Opticians say eye examinations are essential before buying glasses.
As well as ensuring the correct prescription is used, they can detect serious health issues, such as cataracts and brain tumours.
Last updated at 1:08 AM on 31st October 2010
They may save you money in the short term but cheap reading glasses could end up costing your eyesight.
The so-called ‘ready readers’, which sell for as little as £1 in high street shops, may leave wearers with eye strain, headaches or even blurred or double vision.
Millions have bought them after baulking at the high cost of buying glasses from an optician.
However, research suggests they could be putting their eyesight and health at risk.
By the age of 50, most adults have problems reading a book or newspaper without spectacles.
So the arrival of the cheap glasses in supermarkets, high street stores and market stalls less than ten years ago has been seen as a saviour for many
A consumer might have to pay more than £100 for a pair of reading glasses from an optician, which might easily be lost or broken.
Instead, many buy several cheap versions to stash around the house so that they can always find a pair.
A researcher at consumer champion Which? checked 14 pairs from seven high street chains.
He found problems with half of them, with those carrying a higher prescription – +3.5 to +4 – considered to cause the most concern. ‘Off-the-peg glasses could cause eye strain, blurred vision, headaches or double vision,’ the Which? researcher said.
‘For people with higher prescriptions, they’re not suitable for walking or other mobile activities.’
They could even ‘cause a nasty accident’, he warned.
The biggest problem is that the centre point of the two lenses might not be aligned.
This means the sight in one eye might be clear while the other is blurred. This was the case in a pair from Poundland – which also had a prescription strength that differed from the +3.5 on the pack – and a £16 pair from fashion eyewear store Sight Station.
‘This could cause eye problems or a head tilt,’ the researcher said.
A £4 pair from Tiger were ‘unwearable’ because the centre point of the lenses did not match, while a £2 pair from Primark had ‘a very large difference’.
A £15 pair from Marks & Spencer were so ‘poorly made’ that the lenses were likely to drop out.
Which? advises people who have a prescription above +2 to test reading glasses for two minutes to check the centre points of each lens are aligned correctly.
Opticians say eye examinations are essential before buying glasses.
As well as ensuring the correct prescription is used, they can detect serious health issues, such as cataracts and brain tumours.
Can Boomers Throw Away Their Reading Glasses?
By John Gever, Senior Editor, MedPage Today
Published: October 25, 2010
Reviewed by Robert Jasmer, MD; Associate Clinical Professor of Medicine, University of California, San Francisco and
Dorothy Caputo, MA, RN, BC-ADM, CDE, Nurse Planner
CHICAGO -- With the baby-boom generation now firmly in the age range when near-range vision goes blurry, advances in refractive surgery and implants could allow many of them to do away with reading glasses, researchers said here.
A series of presentations at the American Academy of Ophthalmology's annual meeting indicated that new types of intracorneal implants and LASIK-like procedures show promise for eliminating presbyopia, the progressive deterioration of near vision that afflicts virtually everyone older than 45.
Among the innovations highlighted at the meeting: a doughnut-shaped corrective lens inserted under the cornea; a thin disk that restricts the pupillary opening, improving depth of focus in the same way as a pinhole camera; and a noninvasive, implant-free laser procedure that cuts concentric rings in the corneal stroma to alter its refractive power.
None of these are yet approved by the FDA.
At a press briefing, Gustavo Tamayo, MD, of the Bogota Laser Refractive Institute in Bogota, Colombia, described in broad strokes the procedures that are available in South America and Europe, which can target the cornea, the sclera, the anterior chamber, or the lens itself.
Many procedures are owned and developed by U.S. companies, though, and eventual FDA approval is expected. Several of these were the focus of scientific presentations at the AAO meeting, including a report from one U.S. clinical trial.
Intracorneal lens
Ioannis Pallikaris, MD, of the University of Crete in Greece, discussed a recent one-year clinical study with an intracorneal bifocal lens called Flexivue.
The implant has a hole in the center, not as part of its refractive design but to aid in centering it over the pupil.
Session discussant Karl Stonecipher, MD, of TLC Laser Eye Center in Greensboro, N.C., noted that "centration" is a major issue for all types of refractive alteration intended to assist the natural lens -- vision will be imperfect and sometimes worse than before if the corrective intervention is even slightly out of alignment with the lens.
Pallikaris said the lens is 20 microns thick and 3 mm in diameter and is inserted into a pocket created within the stroma with a femtosecond laser.
He reported data on 15 patients with a mean age of 51 receiving the implant -- one per patient in the nondominant eye.
Mean baseline near-vision acuity was 20/50. Within one week of the implant, it improved to 20/32, settling at 20/25 by the third month where it remained for the full year of follow-up in the study.
The bifocal lens also provides a focal point for distance vision, to compensate for the impairment of distance vision that otherwise would result from an anti-presbyopic change in corneal refraction.
In the implanted eye, mean uncorrected distance-vision acuity dropped from 20/20 at baseline to 20/40 during the first month, and then recovered to 20/30 at six months.
Pallikaris noted, though, that uncorrected binocular distance vision remained perfect throughout the entire study, because the artificial lens is placed only in the nondominant eye.
He reported that all of the patients reported their uncorrected near vision after the procedure was excellent or good, and 92% had stopped all use of reading glasses.
Light-restricting disk
Another approach alters the eye's optics not with a lens but with a small disk that reduces the effective pupillary diameter to create a pinhole effect.
Daniel Durrie, MD, of the University of Kansas Medical Center and DurrieVision in Overland Park, Kan., explained that the concept is similar to the F-stop setting of a camera that opens and closes the lens aperture.
A small aperture setting increases the so-called depth of field, such that objects both near and far are in focus. Consequently, this product does not impair distance vision and could actually improve it.
He is leading U.S. testing of the implant, called AcuFocus, which in its current version (the third to date) cuts the effective pupillary diameter from about 4 mm under indoor artificial light to 1.6 mm. The reduction in light transmission is 95%.
As with the Flexivue lens, it's implanted in only one eye. Durrie told MedPage Today that patients do notice that the reduction in light transmission, but it doesn't diminish their overall binocular vision.
The disk also contains 8,400 tiny holes, 5 to 11 microns each, to allow ocular fluids to pass back and forth across the implant to anterior tissues.
Durrie said the implant can be placed under a corneal flap or in a pocket. He said he prefers a flap because it eases positioning and removal, if necessary.
He reported three-year follow-up data from 163 patients receiving two earlier versions of the implant, which were somewhat thicker, with a larger aperture (restricting light by 89% and 93%) and fewer, larger holes for fluid porosity.
Unlike the Flexivue lens and other approaches that change the cornea's refractive properties, the Acufocus lens had almost no impact on the distance acuity, Durrie said.
Among 44 patients receiving the product's first version, the average uncorrected near-vision grade was J2 and mean uncorrected distance vision was 20/25.
The second version, which had a smaller aperture than the first, produced mean uncorrected distance vision of 20/20 and an uncorrected near-vision grade of J1 in 119 patients.
Durrie said a U.S. clinical trial with the third version is now under way in 504 patients. The product is already marketed in Europe and Asia, he said.
He indicated that the disk, at least currently, is not color-matched to the patient's iris and therefore is visible in some patients, especially those with blue eyes. He indicated that one patient didn't like the cosmetic effect and demanded the implant's removal.
Laser-etched rings
A third approach is somewhat similar to laser keratotomy, except that it uses a femtosecond laser to make concentric circular cuts in the stroma.
Mike Holzer, MD, of the University of Heidelberg in Germany, said that procedure takes just 20 seconds once everything is set up.
The arrangement of the rings and the stromal depth can be adjusted to achieve the desired refractive correction, he said.
He also noted that it does not involve any incisions in eye's surface, virtually eliminating infection risk.
He described results in 25 patients with a mean age of 56 treated in mid-2008, with up to 24 months of follow-up available.
At baseline, the patients had uncorrected near vision of 0.70 logMAR units (SD 0.16), equivalent to about 20/100.
Three months after treatment, their mean near-vision acuity had improved to 0.20 logMAR units, or about 20/30, Holzer said.
At 12 months, the mean value worsened slightly to 0.30 logMAR, but among patients evaluable at 18 and 24 months, it was back to 0.20.
Most patients evaluated at 24 months had gained five to six lines of uncorrected near acuity on a standard chart relative to baseline, Holzer said, allowing them to read newspapers held at a normal distance without reading glasses.
He noted that the procedure does induce a degree of myopia for distance vision. "The ideal patient should be a little bit hyperopic [at baseline]," he said.
However, there was no diminution of middle-distance acuity, he added.
At the press briefing, Richard Lindstrom, MD, of Minnesota Eye Consultants in Bloomington, Minn., discussed still other approaches involving the lens -- either replacing it entirely with a multifocal synthetic lens as part of cataract surgery, or implanting a so-called phakic intraocular lens that rests on top of the natural lens.
These also are largely development-stage products in the U.S., though they are marketed elsewhere in the world.
Lindstrom said a major consideration for all these treatments is the limited reimbursement available from third-party payers.
He noted that Medicare has ruled out payment for surgeries and implants for acuity problems that could be corrected with glasses, and private insurers have largely followed suit.
Consequently, at least for the near future, baby boomers facing combination problems such as cataracts, myopia, and presbyopia will have to pay for these do-it-all procedures out of pocket.
Lindstrom said such patients therefore have a decision to make, regarding how much they're willing to pay for uncorrected perfect vision versus settling for cheaper procedures that correct some problems but still leave them needing glasses or contact lenses for driving or reading restaurant menus.
Published: October 25, 2010
Reviewed by Robert Jasmer, MD; Associate Clinical Professor of Medicine, University of California, San Francisco and
Dorothy Caputo, MA, RN, BC-ADM, CDE, Nurse Planner
CHICAGO -- With the baby-boom generation now firmly in the age range when near-range vision goes blurry, advances in refractive surgery and implants could allow many of them to do away with reading glasses, researchers said here.
A series of presentations at the American Academy of Ophthalmology's annual meeting indicated that new types of intracorneal implants and LASIK-like procedures show promise for eliminating presbyopia, the progressive deterioration of near vision that afflicts virtually everyone older than 45.
Among the innovations highlighted at the meeting: a doughnut-shaped corrective lens inserted under the cornea; a thin disk that restricts the pupillary opening, improving depth of focus in the same way as a pinhole camera; and a noninvasive, implant-free laser procedure that cuts concentric rings in the corneal stroma to alter its refractive power.
None of these are yet approved by the FDA.
At a press briefing, Gustavo Tamayo, MD, of the Bogota Laser Refractive Institute in Bogota, Colombia, described in broad strokes the procedures that are available in South America and Europe, which can target the cornea, the sclera, the anterior chamber, or the lens itself.
Many procedures are owned and developed by U.S. companies, though, and eventual FDA approval is expected. Several of these were the focus of scientific presentations at the AAO meeting, including a report from one U.S. clinical trial.
Intracorneal lens
Ioannis Pallikaris, MD, of the University of Crete in Greece, discussed a recent one-year clinical study with an intracorneal bifocal lens called Flexivue.
The implant has a hole in the center, not as part of its refractive design but to aid in centering it over the pupil.
Session discussant Karl Stonecipher, MD, of TLC Laser Eye Center in Greensboro, N.C., noted that "centration" is a major issue for all types of refractive alteration intended to assist the natural lens -- vision will be imperfect and sometimes worse than before if the corrective intervention is even slightly out of alignment with the lens.
Pallikaris said the lens is 20 microns thick and 3 mm in diameter and is inserted into a pocket created within the stroma with a femtosecond laser.
He reported data on 15 patients with a mean age of 51 receiving the implant -- one per patient in the nondominant eye.
Mean baseline near-vision acuity was 20/50. Within one week of the implant, it improved to 20/32, settling at 20/25 by the third month where it remained for the full year of follow-up in the study.
The bifocal lens also provides a focal point for distance vision, to compensate for the impairment of distance vision that otherwise would result from an anti-presbyopic change in corneal refraction.
In the implanted eye, mean uncorrected distance-vision acuity dropped from 20/20 at baseline to 20/40 during the first month, and then recovered to 20/30 at six months.
Pallikaris noted, though, that uncorrected binocular distance vision remained perfect throughout the entire study, because the artificial lens is placed only in the nondominant eye.
He reported that all of the patients reported their uncorrected near vision after the procedure was excellent or good, and 92% had stopped all use of reading glasses.
Light-restricting disk
Another approach alters the eye's optics not with a lens but with a small disk that reduces the effective pupillary diameter to create a pinhole effect.
Daniel Durrie, MD, of the University of Kansas Medical Center and DurrieVision in Overland Park, Kan., explained that the concept is similar to the F-stop setting of a camera that opens and closes the lens aperture.
A small aperture setting increases the so-called depth of field, such that objects both near and far are in focus. Consequently, this product does not impair distance vision and could actually improve it.
He is leading U.S. testing of the implant, called AcuFocus, which in its current version (the third to date) cuts the effective pupillary diameter from about 4 mm under indoor artificial light to 1.6 mm. The reduction in light transmission is 95%.
As with the Flexivue lens, it's implanted in only one eye. Durrie told MedPage Today that patients do notice that the reduction in light transmission, but it doesn't diminish their overall binocular vision.
The disk also contains 8,400 tiny holes, 5 to 11 microns each, to allow ocular fluids to pass back and forth across the implant to anterior tissues.
Durrie said the implant can be placed under a corneal flap or in a pocket. He said he prefers a flap because it eases positioning and removal, if necessary.
He reported three-year follow-up data from 163 patients receiving two earlier versions of the implant, which were somewhat thicker, with a larger aperture (restricting light by 89% and 93%) and fewer, larger holes for fluid porosity.
Unlike the Flexivue lens and other approaches that change the cornea's refractive properties, the Acufocus lens had almost no impact on the distance acuity, Durrie said.
Among 44 patients receiving the product's first version, the average uncorrected near-vision grade was J2 and mean uncorrected distance vision was 20/25.
The second version, which had a smaller aperture than the first, produced mean uncorrected distance vision of 20/20 and an uncorrected near-vision grade of J1 in 119 patients.
Durrie said a U.S. clinical trial with the third version is now under way in 504 patients. The product is already marketed in Europe and Asia, he said.
He indicated that the disk, at least currently, is not color-matched to the patient's iris and therefore is visible in some patients, especially those with blue eyes. He indicated that one patient didn't like the cosmetic effect and demanded the implant's removal.
Laser-etched rings
A third approach is somewhat similar to laser keratotomy, except that it uses a femtosecond laser to make concentric circular cuts in the stroma.
Mike Holzer, MD, of the University of Heidelberg in Germany, said that procedure takes just 20 seconds once everything is set up.
The arrangement of the rings and the stromal depth can be adjusted to achieve the desired refractive correction, he said.
He also noted that it does not involve any incisions in eye's surface, virtually eliminating infection risk.
He described results in 25 patients with a mean age of 56 treated in mid-2008, with up to 24 months of follow-up available.
At baseline, the patients had uncorrected near vision of 0.70 logMAR units (SD 0.16), equivalent to about 20/100.
Three months after treatment, their mean near-vision acuity had improved to 0.20 logMAR units, or about 20/30, Holzer said.
At 12 months, the mean value worsened slightly to 0.30 logMAR, but among patients evaluable at 18 and 24 months, it was back to 0.20.
Most patients evaluated at 24 months had gained five to six lines of uncorrected near acuity on a standard chart relative to baseline, Holzer said, allowing them to read newspapers held at a normal distance without reading glasses.
He noted that the procedure does induce a degree of myopia for distance vision. "The ideal patient should be a little bit hyperopic [at baseline]," he said.
However, there was no diminution of middle-distance acuity, he added.
At the press briefing, Richard Lindstrom, MD, of Minnesota Eye Consultants in Bloomington, Minn., discussed still other approaches involving the lens -- either replacing it entirely with a multifocal synthetic lens as part of cataract surgery, or implanting a so-called phakic intraocular lens that rests on top of the natural lens.
These also are largely development-stage products in the U.S., though they are marketed elsewhere in the world.
Lindstrom said a major consideration for all these treatments is the limited reimbursement available from third-party payers.
He noted that Medicare has ruled out payment for surgeries and implants for acuity problems that could be corrected with glasses, and private insurers have largely followed suit.
Consequently, at least for the near future, baby boomers facing combination problems such as cataracts, myopia, and presbyopia will have to pay for these do-it-all procedures out of pocket.
Lindstrom said such patients therefore have a decision to make, regarding how much they're willing to pay for uncorrected perfect vision versus settling for cheaper procedures that correct some problems but still leave them needing glasses or contact lenses for driving or reading restaurant menus.
Friday, November 26, 2010
Mayo Clinic guide: Home remedies can do the trick
By Janice Lloyd, USA TODAY
In this age of rising medical costs and growing demands on our time, a trip to the doctor is something we hope to avoid.
But how do you keep yourself healthy enough to stay away? And how do you know what illnesses you can treat at home and which need professional attention?
Enter the Mayo Clinic's Book of Home Remedies, a 200-page guide for treating more than 100 common conditions. Savvy parents looking for quick advice and good bedside manner get both from author Philip Hagen, who discusses alternative and conventional approaches to healing, cautions about when to seek medical help and offers advice about how to stay healthy.
"This book reflects our experience in working with people who come to the doctor when there may be something that they can do at home," says Hagen, who specializes in internal and preventive medicine.
"We looked at conditions that had a broad impact on the population for which there seemed to be some reasonable home remedies. Then we asked the experts at Mayo to see if there might be reasonable scientific explanations for them and to determine that they're safe."
The need for families to stretch dollars wasn't overlooked by Hagen and his colleagues at Mayo. "The timeliness of this book is in no small part brought about by increasing medical costs," Hagen says.
The kinds of remedies addressed are as diverse as gentle stretching for back pain, swallowing a teaspoon of sugar for hiccups, trying ginger for morning sickness and using Tylenol for teething. And there are instructions for performing lifesaving moves such as CPR and the Heimlich maneuver.
Allergies
"The best way to approach managing allergies is to know and avoid your allergy triggers," Hagen says.
The most common allergens are inhaled — such as pollen, dust, mold and pet dander. At this time of year, when weed pollen is at its worst, people sensitive to pollen can be particularly miserable. He advises:
•Close windows and doors.
•Don't hang laundry outdoors.
•Use an allergy-grade filter on your heating system.
•Rinse out your sinuses with a nasal lavage.
Insomnia
Insomnia disturbs more than one-third of adults at some point, Hagen says. He suggests lifestyle changes — including getting exercise and taking a warm bath one to two hours before bedtime — before resolving to find other ways (antihistamines, sleeping pills) to improve sleep.
•Try gentle exercise like stretching to relax.
•Take a warm bath one to two hours before bedtime.
•Limit naps to 20 or 30 minutes.
Heartburn
Prevention is the key. If you can follow the drill, you won't need a remedy. Still get hit with heartburn? Over-the-counter remedies such as antacids and Pepcid will help.
•Maintain a healthy weight.
•Avoid food and drink that can trigger heartburn. These include fatty foods, alcohol, peppermint and tomato products.
•Don't eat two to three hours before bed.
Influenza
If you get the flu, rest, drink plenty of fluids, try chicken soup — which the authors say helps break up sinus congestion — and consider pain relievers, "but remember, they only make you feel better and can have side effects." Best to take preventive steps:
•Get a flu shot in October or November.
•Wash your hands.
•Eat right and sleep tight.
In this age of rising medical costs and growing demands on our time, a trip to the doctor is something we hope to avoid.
But how do you keep yourself healthy enough to stay away? And how do you know what illnesses you can treat at home and which need professional attention?
Enter the Mayo Clinic's Book of Home Remedies, a 200-page guide for treating more than 100 common conditions. Savvy parents looking for quick advice and good bedside manner get both from author Philip Hagen, who discusses alternative and conventional approaches to healing, cautions about when to seek medical help and offers advice about how to stay healthy.
"This book reflects our experience in working with people who come to the doctor when there may be something that they can do at home," says Hagen, who specializes in internal and preventive medicine.
"We looked at conditions that had a broad impact on the population for which there seemed to be some reasonable home remedies. Then we asked the experts at Mayo to see if there might be reasonable scientific explanations for them and to determine that they're safe."
The need for families to stretch dollars wasn't overlooked by Hagen and his colleagues at Mayo. "The timeliness of this book is in no small part brought about by increasing medical costs," Hagen says.
The kinds of remedies addressed are as diverse as gentle stretching for back pain, swallowing a teaspoon of sugar for hiccups, trying ginger for morning sickness and using Tylenol for teething. And there are instructions for performing lifesaving moves such as CPR and the Heimlich maneuver.
Allergies
"The best way to approach managing allergies is to know and avoid your allergy triggers," Hagen says.
The most common allergens are inhaled — such as pollen, dust, mold and pet dander. At this time of year, when weed pollen is at its worst, people sensitive to pollen can be particularly miserable. He advises:
•Close windows and doors.
•Don't hang laundry outdoors.
•Use an allergy-grade filter on your heating system.
•Rinse out your sinuses with a nasal lavage.
Insomnia
Insomnia disturbs more than one-third of adults at some point, Hagen says. He suggests lifestyle changes — including getting exercise and taking a warm bath one to two hours before bedtime — before resolving to find other ways (antihistamines, sleeping pills) to improve sleep.
•Try gentle exercise like stretching to relax.
•Take a warm bath one to two hours before bedtime.
•Limit naps to 20 or 30 minutes.
Heartburn
Prevention is the key. If you can follow the drill, you won't need a remedy. Still get hit with heartburn? Over-the-counter remedies such as antacids and Pepcid will help.
•Maintain a healthy weight.
•Avoid food and drink that can trigger heartburn. These include fatty foods, alcohol, peppermint and tomato products.
•Don't eat two to three hours before bed.
Influenza
If you get the flu, rest, drink plenty of fluids, try chicken soup — which the authors say helps break up sinus congestion — and consider pain relievers, "but remember, they only make you feel better and can have side effects." Best to take preventive steps:
•Get a flu shot in October or November.
•Wash your hands.
•Eat right and sleep tight.
Heavy Smoking Linked to Alzheimer's in Study
Risk soars for those puffing more than two packs a day, researchers say
By Steven Reinberg
HealthDay Reporter
MONDAY, Oct. 25 (HealthDay News) -- Heavy smoking in middle age seems to increase the risk for developing Alzheimer's disease or another dementia, a large new study suggests.
"We found that people who reported heavy smoking in midlife had more than a 100 percent increase in risk of Alzheimer's disease and vascular dementia," said lead researcher Rachel A. Whitmer, a research scientist in Kaiser Permanente's Division of Research in Oakland, Calif.
"We have known that smoking is a risk factor for cancer, stroke and cardiovascular disease," she said. "This adds to the evidence that what is bad for the heart is bad for the brain."
The report is published in the Oct. 25 online edition of the Archives of Internal Medicine.
For the study, Whitmer's group collected data on 21,123 ethnically diverse people in the Kaiser Permanente health care system who were surveyed between 1978 and 1985, when they were 50 to 60 years old.
During an average follow-up of 23 years, the researchers found that 25.4 percent were diagnosed with dementia, including Alzheimer's (1,136 people) or vascular dementia (416 people), which is the second most common form of dementia after Alzheimer's disease. Vascular dementia is caused by damage to the arteries in the brain.
Compared with non-smokers, those who smoked more than two packs of cigarettes a day in midlife had a "dramatic increase" in the incidence of dementia -- more than a 157 percent increased risk of developing Alzheimer's disease and a 172 percent increased risk of developing vascular dementia, Whitmer's team found.
Former smokers and people who smoked less than half a pack a day did not appear to be at increased risk of Alzheimer's or vascular dementia, the researchers note.
The associations between smoking and dementia did not change even after adjusting for race or gender, high blood pressure, high cholesterol or heart attack, stroke or weight, they add.
A link between Alzheimer's and smoking has been shown before, but this new study pinpoints the specific risk for middle-age smokers for developing both Alzheimer's and vascular dementia, the researchers say.
Smoking, an established risk factor for stroke, may contribute to the likelihood of vascular dementia by causing small clots in the brain. Smoking also contributes to oxidative stress and inflammation, which may be linked to the risk of developing Alzheimer's disease, the researchers say.
"The brain is not immune to long-term damage from smoking," Whitmer said.
Two smaller studies of predominantly white participants also suggested that mid-life smoking raised the risk of developing Alzheimer's, researchers noted.
Commenting on the new study, William Thies, chief medical and scientific officer at the Alzheimer's Association, said "this is a sound confirmation of something that's been known for a while."
Another expert, Dr. Samuel E. Gandy, the Mount Sinai Professor of Alzheimer's Disease Research at Mount Sinai School of Medicine in New York City, said the findings are promising.
"Environmental factors in Alzheimer's disease have been long sought, and, until now, only head injury has emerged," Gandy said. "Unlike head injury, a tobacco smoking association is especially important because that is a risk that can be modified."
By Steven Reinberg
HealthDay Reporter
MONDAY, Oct. 25 (HealthDay News) -- Heavy smoking in middle age seems to increase the risk for developing Alzheimer's disease or another dementia, a large new study suggests.
"We found that people who reported heavy smoking in midlife had more than a 100 percent increase in risk of Alzheimer's disease and vascular dementia," said lead researcher Rachel A. Whitmer, a research scientist in Kaiser Permanente's Division of Research in Oakland, Calif.
"We have known that smoking is a risk factor for cancer, stroke and cardiovascular disease," she said. "This adds to the evidence that what is bad for the heart is bad for the brain."
The report is published in the Oct. 25 online edition of the Archives of Internal Medicine.
For the study, Whitmer's group collected data on 21,123 ethnically diverse people in the Kaiser Permanente health care system who were surveyed between 1978 and 1985, when they were 50 to 60 years old.
During an average follow-up of 23 years, the researchers found that 25.4 percent were diagnosed with dementia, including Alzheimer's (1,136 people) or vascular dementia (416 people), which is the second most common form of dementia after Alzheimer's disease. Vascular dementia is caused by damage to the arteries in the brain.
Compared with non-smokers, those who smoked more than two packs of cigarettes a day in midlife had a "dramatic increase" in the incidence of dementia -- more than a 157 percent increased risk of developing Alzheimer's disease and a 172 percent increased risk of developing vascular dementia, Whitmer's team found.
Former smokers and people who smoked less than half a pack a day did not appear to be at increased risk of Alzheimer's or vascular dementia, the researchers note.
The associations between smoking and dementia did not change even after adjusting for race or gender, high blood pressure, high cholesterol or heart attack, stroke or weight, they add.
A link between Alzheimer's and smoking has been shown before, but this new study pinpoints the specific risk for middle-age smokers for developing both Alzheimer's and vascular dementia, the researchers say.
Smoking, an established risk factor for stroke, may contribute to the likelihood of vascular dementia by causing small clots in the brain. Smoking also contributes to oxidative stress and inflammation, which may be linked to the risk of developing Alzheimer's disease, the researchers say.
"The brain is not immune to long-term damage from smoking," Whitmer said.
Two smaller studies of predominantly white participants also suggested that mid-life smoking raised the risk of developing Alzheimer's, researchers noted.
Commenting on the new study, William Thies, chief medical and scientific officer at the Alzheimer's Association, said "this is a sound confirmation of something that's been known for a while."
Another expert, Dr. Samuel E. Gandy, the Mount Sinai Professor of Alzheimer's Disease Research at Mount Sinai School of Medicine in New York City, said the findings are promising.
"Environmental factors in Alzheimer's disease have been long sought, and, until now, only head injury has emerged," Gandy said. "Unlike head injury, a tobacco smoking association is especially important because that is a risk that can be modified."
Saturday, November 20, 2010
Vitamin A pill 'could save the sight of millions as they get older'
By Fiona Macrae
Last updated at 2:07 AM on 18th October 2010
A drug based on vitamin A could prevent millions from going blind as they get older, doctors believe.
The treatment was able to stop the most common cause of blindness in old age during trials.
Researchers behind the drug, fenretinide, found it halted the advance of age-related macular degeneration, for which there is currently no cure.
They targeted the most prevalent form of the condition, known as ‘dry’ AMD, which is caused by the deterioration and death of cells in the macula – the part of the retina used to see straight ahead.
The disease robs sufferers of their sight by creating a blackspot in the centre of their vision.
It can make it impossible to carry out everyday tasks such as reading, driving and watching television.
While the less common ‘wet’ form can be treated, nothing can be done to help the bulk of patients.
The U.S. research studied fenretinide, which is derived from vitamin A, the vitamin found in carrots, and which was originally designed to tackle arthritis.
Almost 250 men and women with dry AMD took a fenretinide pill a day or a placebo.
In the highest dose, the drug halted visual deterioration after a year. This suggests that while it was unable to do anything to stop cells that were already damaged from dying, it protected healthy cells. Although the research is still preliminary, it offers promise of a treatment for the disease.
It affects millions across the world and 300,000 Britons. The number of UK sufferers could more than treble to one million within 25 years as the population ages.
Dr Jason Slakter, of New York University School of Medicine, said: ‘There are currently no effective treatments for dry AMD and the need for finding one is grave.
‘Our study wasn’t designed to give a final answer.
‘It was designed to see if there was a biological effect and if the drug was working in the way we’d expect and to find out if it was well tolerated by patents.
‘I think we answered all of these points favourably. The bottom line is that I am excited about doing more studies.’
Further, larger trials are planned for the end of next year.
If the drug lives up to its initial promise, it could be in widespread use for dry AMD by 2015.
The treatment works because in normal circumstances the eye needs vitamin A to help it see. The retina naturally uses the vitamin and is helped to do so by a compound called retinol binding protein, or RBP.
However in some patients, the vitamin can produce poisons that kill the delicate cells, leading to loss of vision.
Fenretinide acts as a decoy, attaching itself to the RBP and stopping vitamin A from causing harm, the American Academy of Ophthalmology’s annual conference heard.
Wet AMD, in which tiny blood vessels bleed into the retina, is less common, but progresses more rapidly, with central vision being lost within months of diagnosis.
Caught early enough, wet AMD can be stopped in its tracks by a technique called photodynamic therapy, which uses a light-activated dye to destroy abnormal blood vessels. Drug treatments are also available.
Fenretinide also halved the odds of the patients, who already had dry AMD, going on to develop wet AMD.
A spokesman for the research team said: ‘Years of use of fenretinide to treat cancers, rheumatoid arthritis have shown it to be safe and well-tolerated.’
Last updated at 2:07 AM on 18th October 2010
A drug based on vitamin A could prevent millions from going blind as they get older, doctors believe.
The treatment was able to stop the most common cause of blindness in old age during trials.
Researchers behind the drug, fenretinide, found it halted the advance of age-related macular degeneration, for which there is currently no cure.
They targeted the most prevalent form of the condition, known as ‘dry’ AMD, which is caused by the deterioration and death of cells in the macula – the part of the retina used to see straight ahead.
The disease robs sufferers of their sight by creating a blackspot in the centre of their vision.
It can make it impossible to carry out everyday tasks such as reading, driving and watching television.
While the less common ‘wet’ form can be treated, nothing can be done to help the bulk of patients.
The U.S. research studied fenretinide, which is derived from vitamin A, the vitamin found in carrots, and which was originally designed to tackle arthritis.
Almost 250 men and women with dry AMD took a fenretinide pill a day or a placebo.
In the highest dose, the drug halted visual deterioration after a year. This suggests that while it was unable to do anything to stop cells that were already damaged from dying, it protected healthy cells. Although the research is still preliminary, it offers promise of a treatment for the disease.
It affects millions across the world and 300,000 Britons. The number of UK sufferers could more than treble to one million within 25 years as the population ages.
Dr Jason Slakter, of New York University School of Medicine, said: ‘There are currently no effective treatments for dry AMD and the need for finding one is grave.
‘Our study wasn’t designed to give a final answer.
‘It was designed to see if there was a biological effect and if the drug was working in the way we’d expect and to find out if it was well tolerated by patents.
‘I think we answered all of these points favourably. The bottom line is that I am excited about doing more studies.’
Further, larger trials are planned for the end of next year.
If the drug lives up to its initial promise, it could be in widespread use for dry AMD by 2015.
The treatment works because in normal circumstances the eye needs vitamin A to help it see. The retina naturally uses the vitamin and is helped to do so by a compound called retinol binding protein, or RBP.
However in some patients, the vitamin can produce poisons that kill the delicate cells, leading to loss of vision.
Fenretinide acts as a decoy, attaching itself to the RBP and stopping vitamin A from causing harm, the American Academy of Ophthalmology’s annual conference heard.
Wet AMD, in which tiny blood vessels bleed into the retina, is less common, but progresses more rapidly, with central vision being lost within months of diagnosis.
Caught early enough, wet AMD can be stopped in its tracks by a technique called photodynamic therapy, which uses a light-activated dye to destroy abnormal blood vessels. Drug treatments are also available.
Fenretinide also halved the odds of the patients, who already had dry AMD, going on to develop wet AMD.
A spokesman for the research team said: ‘Years of use of fenretinide to treat cancers, rheumatoid arthritis have shown it to be safe and well-tolerated.’
Researchers Say "Poppers" May Damage Eyes.
Not yet clear how widespread these cases might be, experts say
By Alan Mozes
HealthDay Reporter
WEDNESDAY, Oct. 13 (HealthDay News) -- The legal recreational drugs known as "poppers" appear to be linked to light sensitivity and vision loss in at least several healthy individuals, a new French review of cases reveals.
Poppers -- a catch-all term for alkyl nitrites that are often inhaled by partyers for a brief "head rush" and to increase sexual arousal -- may compromise the normal workings of photoreceptor cells found in a key region of the eye's retina, the researchers say.
"We believe that in fact this complication is quite common," said Dr. Michel Paques of the Quinze-Vingts National Hospital in Paris. However, early data suggests that "only a minority of [affected] consumers will show up to the ophthalmologist," he added. That's because popper-related retinal damage may not noticeably affect vision in some cases and may therefore go undiagnosed, he said.
Paques and his colleagues report their observations, based on four patients, in a correspondence to the Oct. 14 issue of the New England Journal of Medicine.
Popular for decades particularly among the gay community, poppers are perceived by many as being relatively safe. They are typically sold over the counter in small bottles.
But nitric oxide is known to affect the metabolism of photoreceptors, the authors note, and can also alter the operation of a key enzyme involved in photoreceptor function.
The authors report on four recent cases, which took place earlier this year within a three-month period.
In one instance, a 27-year old woman experienced eye trouble the day after she inhaled poppers (and drank alcohol) at a party. After 11 days of seeing a "central bright dot" in both of her eyes, she sought medical attention.
An exam turned up no prior history of significant health or eye problems. But her eyesight was found to be less than ideal -- 20/50 in the right eye and 20/40 in the left eye -- and she had a yellow dot on the foveal portion of her eyes, alongside damage to the outer photoreceptor segment of both eyes.
The fovea facilitates the sharp central vision needed for reading, driving, and viewing movies.
One month later, her visual symptoms and physical damage remained unchanged, the research team noted.
Over the following three months, three more patients sought care for similar visual symptoms arising after popper use. Although symptoms did not appear to worsen over time, the researchers noted that just two of the four patients have fully recovered. Meanwhile, the exact underlying mechanics of the apparent poppers-vision risk connection remains unclear.
"Those who did stop taking poppers showed progressive recovery over several months," Paques said.
Before these patients sought treatment, the authors note that only two similar cases had been reported over the prior decade. However, Paques said the occurrence may not be as rare as it seems.
"Since our initial (report) we actively searched for new cases and were surprised to find many of them, sometimes not diagnosed by previous ophthalmologists because the retinal abnormalities are in a small -- yet very important -- area of the retina," he said.
Based on their findings, Paques and colleagues advise eye doctors and potential users of poppers to be aware of the potential risk for popper-related retinal toxicity.
"Even a single dose of poppers may affect the retina," he cautioned. Patients should visit an eye doctor "if there are any symptoms such as bright light in the center of the visual field, or if there is persistent visual loss, for instance, difficulty in reading small letters."
Not all eye specialists are alarmed, however. Dr. Richard Bensinger, a Seattle-based ophthalmologist and spokesman for the American Academy of Ophthalmology, said evidence to date appears to be entirely anecdotal and does not yet suggest a clear cause-and-effect between poppers and vision trouble.
"We have no real detailed history," he noted. "It's just these patients reporting what they had done, and it certainly does sound like there was something in their activity that caused a problem, but it's not necessarily poppers that cause the problem. Because many, many people have taken them all over the planet without any visual incident."
Perhaps the poppers were adulterated in some way, he suggested. "We don't know. So it's worth looking into further," he said.
By Alan Mozes
HealthDay Reporter
WEDNESDAY, Oct. 13 (HealthDay News) -- The legal recreational drugs known as "poppers" appear to be linked to light sensitivity and vision loss in at least several healthy individuals, a new French review of cases reveals.
Poppers -- a catch-all term for alkyl nitrites that are often inhaled by partyers for a brief "head rush" and to increase sexual arousal -- may compromise the normal workings of photoreceptor cells found in a key region of the eye's retina, the researchers say.
"We believe that in fact this complication is quite common," said Dr. Michel Paques of the Quinze-Vingts National Hospital in Paris. However, early data suggests that "only a minority of [affected] consumers will show up to the ophthalmologist," he added. That's because popper-related retinal damage may not noticeably affect vision in some cases and may therefore go undiagnosed, he said.
Paques and his colleagues report their observations, based on four patients, in a correspondence to the Oct. 14 issue of the New England Journal of Medicine.
Popular for decades particularly among the gay community, poppers are perceived by many as being relatively safe. They are typically sold over the counter in small bottles.
But nitric oxide is known to affect the metabolism of photoreceptors, the authors note, and can also alter the operation of a key enzyme involved in photoreceptor function.
The authors report on four recent cases, which took place earlier this year within a three-month period.
In one instance, a 27-year old woman experienced eye trouble the day after she inhaled poppers (and drank alcohol) at a party. After 11 days of seeing a "central bright dot" in both of her eyes, she sought medical attention.
An exam turned up no prior history of significant health or eye problems. But her eyesight was found to be less than ideal -- 20/50 in the right eye and 20/40 in the left eye -- and she had a yellow dot on the foveal portion of her eyes, alongside damage to the outer photoreceptor segment of both eyes.
The fovea facilitates the sharp central vision needed for reading, driving, and viewing movies.
One month later, her visual symptoms and physical damage remained unchanged, the research team noted.
Over the following three months, three more patients sought care for similar visual symptoms arising after popper use. Although symptoms did not appear to worsen over time, the researchers noted that just two of the four patients have fully recovered. Meanwhile, the exact underlying mechanics of the apparent poppers-vision risk connection remains unclear.
"Those who did stop taking poppers showed progressive recovery over several months," Paques said.
Before these patients sought treatment, the authors note that only two similar cases had been reported over the prior decade. However, Paques said the occurrence may not be as rare as it seems.
"Since our initial (report) we actively searched for new cases and were surprised to find many of them, sometimes not diagnosed by previous ophthalmologists because the retinal abnormalities are in a small -- yet very important -- area of the retina," he said.
Based on their findings, Paques and colleagues advise eye doctors and potential users of poppers to be aware of the potential risk for popper-related retinal toxicity.
"Even a single dose of poppers may affect the retina," he cautioned. Patients should visit an eye doctor "if there are any symptoms such as bright light in the center of the visual field, or if there is persistent visual loss, for instance, difficulty in reading small letters."
Not all eye specialists are alarmed, however. Dr. Richard Bensinger, a Seattle-based ophthalmologist and spokesman for the American Academy of Ophthalmology, said evidence to date appears to be entirely anecdotal and does not yet suggest a clear cause-and-effect between poppers and vision trouble.
"We have no real detailed history," he noted. "It's just these patients reporting what they had done, and it certainly does sound like there was something in their activity that caused a problem, but it's not necessarily poppers that cause the problem. Because many, many people have taken them all over the planet without any visual incident."
Perhaps the poppers were adulterated in some way, he suggested. "We don't know. So it's worth looking into further," he said.
Wednesday, November 3, 2010
Kids Playing With Laser Pointers May Be Aiming for Eye Trouble
Teen boy damages retina with Internet-purchased 'toy,' doctors say
By Serena Gordon
HealthDay Reporter
WEDNESDAY, Sept. 8 (HealthDay News) -- A 15-year-old Swiss boy attempted to create his own laser show using a laser pointer he bought on the Internet and a mirror. Instead, he inadvertently beamed the laser into his eyes, creating permanent damage to his vision.
"These high-power laser products are very dangerous," said Dr. Martin Schmid, head of the retina unit in the department of ophthalmology at Lucerne Cantonal Hospital in Switzerland. Schmid is also one of the authors of the case report detailing the young boy's eye damage in a letter in the Sept. 9 issue of the New England Journal of Medicine.
Schmid said that part of the problem is that not all laser pointers are labeled properly, so it's not always easy to know if you have a pointer that could create serious damage. One sure way to know if you have a potentially dangerous laser pointer is if the laser can burn through paper, explained Schmid.
"Every laser pointer which is capable of burning holes into paper or of lighting matches or of popping balloons is highly dangerous for the eye and must not be used by non-professionals," he cautioned.
Those are exactly some of the uses the Swiss youngster was planning for his laser pointer. He told doctors that he purchased the laser pointer so that he could pop balloons from a distance, burn holes in paper cards and burn holes in his sister's sneakers.
While he was attempting his "laser light show," the teen said that the laser beam hit his eyes several times. Although he immediately noticed that his vision was blurry, he was afraid to tell his parents what had happened. He waited two weeks before letting them know that he was still experiencing blurred vision.
The vision in his left eye was so damaged that he couldn't count how many fingers a doctor was holding up until they were just three feet away. His visual acuity in his right eye was 20/50.
Schmid said the boy wasn't sure if the laser was dangerous, and he definitely didn't know it could cause immediate eye injury.
When the teenager's eyes were examined, doctors discovered that there had been significant internal bleeding in the left eye and that there were several small scars in the right eye. Even with treatment, there's still a scar that diminished the boy's vision in his left eye. However, his visual acuity has returned to near normal, according to the report.
The laser used by the boy produced an output of 150 milliwatts (mW), far above the maximal output of 5 mW that's expected from a laser pointer sold to the public. The authors point out that it's possible to purchase laser pointers as strong as 700 mW, although such a device may not look any different than a lower-powered device.
Additionally, Schmid said there are instructions available over the Internet for turning low-power devices into high-powered ones.
And, the authors pointed out, high-powered laser pointers can produce immediate and severe retinal injury -- so severe that even blindness can occur.
Dr. Roy Chuck, chair of ophthalmology and visual sciences at Montefiore Medical Center and the Albert Einstein College of Medicine in New York City, said, "We've seen lots of cases of laser burns, usually from researchers giving presentations, but now we're seeing more cases of people ordering these products over the Internet, though eye injuries in lay people are still pretty rare."
Chuck said that children shouldn't have access to laser pointers. "They're not giving presentations, so why would they need to have them?" He said that when it comes to laser toys -- like those used for laser tag -- buying a well-known name brand may be helpful in this case. "When you're buying off the Internet, it's not as regulated and you just can't tell what the strength of the laser is," noted Chuck.
Schmid added that lasers used in toys will generally be labeled as Class 1, although he said that products aren't always labeled properly.
And, even if you've purchased a "safe" laser toy, it's possible that creative children may turn to the Internet and figure out ways to boost the power of the laser. "By searching YouTube for 'burning laser pointers,' you will find a huge amount of videos showing such dangerous experiments. Moreover, there is an increasing number of homepages and videos demonstrating how to turn legal low-power lasers into burning, high-power lasers," said Schmid.
By Serena Gordon
HealthDay Reporter
WEDNESDAY, Sept. 8 (HealthDay News) -- A 15-year-old Swiss boy attempted to create his own laser show using a laser pointer he bought on the Internet and a mirror. Instead, he inadvertently beamed the laser into his eyes, creating permanent damage to his vision.
"These high-power laser products are very dangerous," said Dr. Martin Schmid, head of the retina unit in the department of ophthalmology at Lucerne Cantonal Hospital in Switzerland. Schmid is also one of the authors of the case report detailing the young boy's eye damage in a letter in the Sept. 9 issue of the New England Journal of Medicine.
Schmid said that part of the problem is that not all laser pointers are labeled properly, so it's not always easy to know if you have a pointer that could create serious damage. One sure way to know if you have a potentially dangerous laser pointer is if the laser can burn through paper, explained Schmid.
"Every laser pointer which is capable of burning holes into paper or of lighting matches or of popping balloons is highly dangerous for the eye and must not be used by non-professionals," he cautioned.
Those are exactly some of the uses the Swiss youngster was planning for his laser pointer. He told doctors that he purchased the laser pointer so that he could pop balloons from a distance, burn holes in paper cards and burn holes in his sister's sneakers.
While he was attempting his "laser light show," the teen said that the laser beam hit his eyes several times. Although he immediately noticed that his vision was blurry, he was afraid to tell his parents what had happened. He waited two weeks before letting them know that he was still experiencing blurred vision.
The vision in his left eye was so damaged that he couldn't count how many fingers a doctor was holding up until they were just three feet away. His visual acuity in his right eye was 20/50.
Schmid said the boy wasn't sure if the laser was dangerous, and he definitely didn't know it could cause immediate eye injury.
When the teenager's eyes were examined, doctors discovered that there had been significant internal bleeding in the left eye and that there were several small scars in the right eye. Even with treatment, there's still a scar that diminished the boy's vision in his left eye. However, his visual acuity has returned to near normal, according to the report.
The laser used by the boy produced an output of 150 milliwatts (mW), far above the maximal output of 5 mW that's expected from a laser pointer sold to the public. The authors point out that it's possible to purchase laser pointers as strong as 700 mW, although such a device may not look any different than a lower-powered device.
Additionally, Schmid said there are instructions available over the Internet for turning low-power devices into high-powered ones.
And, the authors pointed out, high-powered laser pointers can produce immediate and severe retinal injury -- so severe that even blindness can occur.
Dr. Roy Chuck, chair of ophthalmology and visual sciences at Montefiore Medical Center and the Albert Einstein College of Medicine in New York City, said, "We've seen lots of cases of laser burns, usually from researchers giving presentations, but now we're seeing more cases of people ordering these products over the Internet, though eye injuries in lay people are still pretty rare."
Chuck said that children shouldn't have access to laser pointers. "They're not giving presentations, so why would they need to have them?" He said that when it comes to laser toys -- like those used for laser tag -- buying a well-known name brand may be helpful in this case. "When you're buying off the Internet, it's not as regulated and you just can't tell what the strength of the laser is," noted Chuck.
Schmid added that lasers used in toys will generally be labeled as Class 1, although he said that products aren't always labeled properly.
And, even if you've purchased a "safe" laser toy, it's possible that creative children may turn to the Internet and figure out ways to boost the power of the laser. "By searching YouTube for 'burning laser pointers,' you will find a huge amount of videos showing such dangerous experiments. Moreover, there is an increasing number of homepages and videos demonstrating how to turn legal low-power lasers into burning, high-power lasers," said Schmid.
Thursday, October 28, 2010
Experimental Synthetic Cornea May Provide Alternative To Cadaver Corneas.
By Fiona MacRae from the UK Daily Mail
Button-shaped artificial corneas have restored the sight in men and women in danger of going blind.
The man-made corneas were just as good at improving eyesight as those usually obtained from donors.
In time, the transparent implants could help ease the dire shortage of donated corneas.
Around 3,000 transplants are carried out in the UK each year but hundreds more could have benefited from the surgery.
Worldwide, 1.5million people go blind each year because they cannot have corneal transplants.
Damage to the cornea, the collagen-based transparent outermost layer of the eye, is one of the most common causes of blindness. It affects ten million people around the world and can be caused by genetics, surgery, burns, infection or chemotherapy.
Previous attempts to develop synthetic implants have had limited success. To create an implant that is as close as the real thing as possible, the North American and Swedish researchers grew a synthetic form of human collagen in the lab and moulded it into wafer-thin button-like shapes.
Ten men and women with corneal disease had the damaged tissue scraped away from the surface of the eye and replaced with a man-made cornea in a half-hour operation.
Over time, the patients were able to blink and cry and the nerves severed by the surgery mended.
Fitted with contact lenses, the patients were able to see as well as people who had conventional corneal transplants, the journal Science Translational Medicine reports. Two years after the op, the lab- grown corneas were still working well.
Using ' biosynthetic' corneas removes the risks of disease and rejection associated with corneas taken from donors after death.
Dr May Griffith, of the University of Ottawa in Canada and Linkoping University in southern Sweden, said: 'This study is important because it is the first to show that an artificially fabricated cornea can integrate within the human eye and stimulate regeneration.
' With further research, this approach could help restore sight to millions of people who are waiting for a donated cornea for transplantation.
The journal reported: ' The see-through nature of the cornea is easily destroyed by trauma or infection but replacement human corneas can be inserted and reliably restore vision.
'The problem is that the shortage of donated corneas leaves millions of people likely to go blind. An alternative source of corneas could make a big difference.
'These biosynthetic corneas may soon allow patients who need transplants but do not have donors to regain normal sight.'
Barbara McLaughlan, of the Royal National Institute of Blind People, said: 'This is potentially an exciting new development for patients with corneal blindness where currently transplant from a human donor is the only treatment opt ion available.
'The first results of this small scale trial in humans seem very encouraging, however mor e research is needed to determine if this could work for all types of corneal blindness and become a widely available treatment.
'RNIB is committed to reducing the number of people who lose their sight unnecessarily, and will follow developments in the hope that the potential of biosynthetic corneas to save sight can be realised.'
Button-shaped artificial corneas have restored the sight in men and women in danger of going blind.
The man-made corneas were just as good at improving eyesight as those usually obtained from donors.
In time, the transparent implants could help ease the dire shortage of donated corneas.
Around 3,000 transplants are carried out in the UK each year but hundreds more could have benefited from the surgery.
Worldwide, 1.5million people go blind each year because they cannot have corneal transplants.
Damage to the cornea, the collagen-based transparent outermost layer of the eye, is one of the most common causes of blindness. It affects ten million people around the world and can be caused by genetics, surgery, burns, infection or chemotherapy.
Previous attempts to develop synthetic implants have had limited success. To create an implant that is as close as the real thing as possible, the North American and Swedish researchers grew a synthetic form of human collagen in the lab and moulded it into wafer-thin button-like shapes.
Ten men and women with corneal disease had the damaged tissue scraped away from the surface of the eye and replaced with a man-made cornea in a half-hour operation.
Over time, the patients were able to blink and cry and the nerves severed by the surgery mended.
Fitted with contact lenses, the patients were able to see as well as people who had conventional corneal transplants, the journal Science Translational Medicine reports. Two years after the op, the lab- grown corneas were still working well.
Using ' biosynthetic' corneas removes the risks of disease and rejection associated with corneas taken from donors after death.
Dr May Griffith, of the University of Ottawa in Canada and Linkoping University in southern Sweden, said: 'This study is important because it is the first to show that an artificially fabricated cornea can integrate within the human eye and stimulate regeneration.
' With further research, this approach could help restore sight to millions of people who are waiting for a donated cornea for transplantation.
The journal reported: ' The see-through nature of the cornea is easily destroyed by trauma or infection but replacement human corneas can be inserted and reliably restore vision.
'The problem is that the shortage of donated corneas leaves millions of people likely to go blind. An alternative source of corneas could make a big difference.
'These biosynthetic corneas may soon allow patients who need transplants but do not have donors to regain normal sight.'
Barbara McLaughlan, of the Royal National Institute of Blind People, said: 'This is potentially an exciting new development for patients with corneal blindness where currently transplant from a human donor is the only treatment opt ion available.
'The first results of this small scale trial in humans seem very encouraging, however mor e research is needed to determine if this could work for all types of corneal blindness and become a widely available treatment.
'RNIB is committed to reducing the number of people who lose their sight unnecessarily, and will follow developments in the hope that the potential of biosynthetic corneas to save sight can be realised.'
Friday, October 22, 2010
Sunglasses Rival Lotions as Vital for Safety
UV rays threaten the eyes as much as the skin, experts warn
By Dennis Thompson
HealthDay Reporter
FRIDAY, Aug. 20 (HealthDay News) -- Folks have been taught to slather on sunscreen, slip on a shirt and clap a hat on their heads to protect their skin from the sun's harmful ultraviolet rays.
That's all good. But not adding a pair of good sunglasses to the ensemble still leaves people at risk, eye doctors say.
Ultraviolet, or UV, rays can cause significant damage to unprotected eyes, resulting in a number of illnesses and disorders that can rob people of their sight.
"People are more aware of skin cancer. There's more awareness of exposing your skin to the sun," said Dr. J. Alberto Martinez, a practicing ophthalmologist in Bethesda, Md., and a clinical professor of ophthalmology at Georgetown University Medical School. "But at the same time, the eyes suffer dramatically from ultraviolet exposure. UV exposure is a public health problem, and, as an ophthalmologist, I see the continuous, serious problems that are caused by UV."
Both short- and long-term exposure to UV rays can cause vision problems and eye damage, according to the U.S. Environmental Protection Agency's Office of Air and Radiation.
People exposed to bright sunlight for even short periods can develop a "sunburn of the eye" in the form of either photokeratitis or photoconjunctivitis.
Photokeratitis is an inflammation of the cornea, the transparent front part of the eye that covers the iris, pupil and lens, according to the World Health Organization. "The sun can cause superficial cells on the front of the cornea to become damaged and die off," said Dr. Lee Duffner, an ophthalmologist in Hollywood, Fla. Photoconjunctivitis is a similar inflammation that affects the conjunctiva, the membrane lining the inside of the eyelids and the eye socket. Both conditions can be very painful, but people tend to recover quickly from them with no long-term damage to their vision.
Long-term UV exposure can do cumulative eye damage over time, causing more insidious and dangerous threats to a person's vision, including:
Pterygium. An abnormal growth of the conjunctiva caused by sun damage that can become so large it grows over and obstructs the cornea, partially blocking vision. Surgery may be required to restore vision. "The bad ones have a tendency to come back, even after they're removed surgically," Duffner said. "They're a real nuisance."
Cataracts. These involve clouding of the eye's lens. Ultraviolet rays are believed to play a part in the process.
Macular degeneration. UV rays that penetrate deep into the eyeball are believed to do damage to the retina, the sheet of nerves along the back wall of the eye that perceive light. The macula, at the center of the retina, is responsible for perception of fine details and a person's central field of vision. "Chesapeake Bay sailors who wear sunglasses and a hat have a much lower incidence of cataracts and macular degeneration than those who don't," Martinez said, citing research.
Cancer. People can develop skin cancer of the eyes as a result of UV damage, according to the WHO. The eye tends to develop melanoma, while the eyelids usually are inflicted with basal cell carcinoma. In both cases, surgery may be necessary.
Of course, such damage doesn't occur just in the summer, or even just when you're standing in sunshine. Bright reflected sunlight from sidewalks, aluminum, snow and other surfaces can cause UV damage just as easily as direct sunlight. In fact, one of the more well-known forms of photokeratitis is snow blindness, which occurs when skiers and climbers are exposed to high levels of UV radiation from light reflected off snow.
So how to protect yourself? Sunglasses. It's that simple, the experts say. A wide-brimmed hat wouldn't hurt, but sunglasses are key.
The sunglasses should be rated to absorb 99 to 100 percent of both UV-A and UV-B radiation. Read the labels. And keep in mind that how much you pay may not guarantee protection.
"It's not really price-related," Duffner said. "I've seen very expensive sunglasses that are not good ultraviolet absorbers, and I've seen cheap sunglasses that were great ultraviolet absorbers."
Also, toss fashion sense out the window, the eye experts say. Small, stylish sunglasses will allow UV radiation to reach the eyes. "If possible, buy wrap-around sunglasses," Duffner said. "With a standard pair of glasses, a fair amount of sunlight still strikes the eye from the side."
The worst forms of UV-related eye disease come from accumulated damage, making it important to start protecting kids' eyes so they will have a better chance of maintaining their vision in their old age.
The bulk of exposure occurs in the first 18 years of life," Martinez said. "The more sun damage you have, the more sensitive you are to later exposure. The trick is to try to get kids to wear sunglasses. It's difficult, but you must try."
By Dennis Thompson
HealthDay Reporter
FRIDAY, Aug. 20 (HealthDay News) -- Folks have been taught to slather on sunscreen, slip on a shirt and clap a hat on their heads to protect their skin from the sun's harmful ultraviolet rays.
That's all good. But not adding a pair of good sunglasses to the ensemble still leaves people at risk, eye doctors say.
Ultraviolet, or UV, rays can cause significant damage to unprotected eyes, resulting in a number of illnesses and disorders that can rob people of their sight.
"People are more aware of skin cancer. There's more awareness of exposing your skin to the sun," said Dr. J. Alberto Martinez, a practicing ophthalmologist in Bethesda, Md., and a clinical professor of ophthalmology at Georgetown University Medical School. "But at the same time, the eyes suffer dramatically from ultraviolet exposure. UV exposure is a public health problem, and, as an ophthalmologist, I see the continuous, serious problems that are caused by UV."
Both short- and long-term exposure to UV rays can cause vision problems and eye damage, according to the U.S. Environmental Protection Agency's Office of Air and Radiation.
People exposed to bright sunlight for even short periods can develop a "sunburn of the eye" in the form of either photokeratitis or photoconjunctivitis.
Photokeratitis is an inflammation of the cornea, the transparent front part of the eye that covers the iris, pupil and lens, according to the World Health Organization. "The sun can cause superficial cells on the front of the cornea to become damaged and die off," said Dr. Lee Duffner, an ophthalmologist in Hollywood, Fla. Photoconjunctivitis is a similar inflammation that affects the conjunctiva, the membrane lining the inside of the eyelids and the eye socket. Both conditions can be very painful, but people tend to recover quickly from them with no long-term damage to their vision.
Long-term UV exposure can do cumulative eye damage over time, causing more insidious and dangerous threats to a person's vision, including:
Pterygium. An abnormal growth of the conjunctiva caused by sun damage that can become so large it grows over and obstructs the cornea, partially blocking vision. Surgery may be required to restore vision. "The bad ones have a tendency to come back, even after they're removed surgically," Duffner said. "They're a real nuisance."
Cataracts. These involve clouding of the eye's lens. Ultraviolet rays are believed to play a part in the process.
Macular degeneration. UV rays that penetrate deep into the eyeball are believed to do damage to the retina, the sheet of nerves along the back wall of the eye that perceive light. The macula, at the center of the retina, is responsible for perception of fine details and a person's central field of vision. "Chesapeake Bay sailors who wear sunglasses and a hat have a much lower incidence of cataracts and macular degeneration than those who don't," Martinez said, citing research.
Cancer. People can develop skin cancer of the eyes as a result of UV damage, according to the WHO. The eye tends to develop melanoma, while the eyelids usually are inflicted with basal cell carcinoma. In both cases, surgery may be necessary.
Of course, such damage doesn't occur just in the summer, or even just when you're standing in sunshine. Bright reflected sunlight from sidewalks, aluminum, snow and other surfaces can cause UV damage just as easily as direct sunlight. In fact, one of the more well-known forms of photokeratitis is snow blindness, which occurs when skiers and climbers are exposed to high levels of UV radiation from light reflected off snow.
So how to protect yourself? Sunglasses. It's that simple, the experts say. A wide-brimmed hat wouldn't hurt, but sunglasses are key.
The sunglasses should be rated to absorb 99 to 100 percent of both UV-A and UV-B radiation. Read the labels. And keep in mind that how much you pay may not guarantee protection.
"It's not really price-related," Duffner said. "I've seen very expensive sunglasses that are not good ultraviolet absorbers, and I've seen cheap sunglasses that were great ultraviolet absorbers."
Also, toss fashion sense out the window, the eye experts say. Small, stylish sunglasses will allow UV radiation to reach the eyes. "If possible, buy wrap-around sunglasses," Duffner said. "With a standard pair of glasses, a fair amount of sunlight still strikes the eye from the side."
The worst forms of UV-related eye disease come from accumulated damage, making it important to start protecting kids' eyes so they will have a better chance of maintaining their vision in their old age.
The bulk of exposure occurs in the first 18 years of life," Martinez said. "The more sun damage you have, the more sensitive you are to later exposure. The trick is to try to get kids to wear sunglasses. It's difficult, but you must try."
Thursday, October 14, 2010
New Gel May Help Speed Healing Of Chronic Wounds, Serious Eye Injuries.
From the Huffington Post:
LONDON — For three years, Connie McPherson had debilitating leg ulcers that were so painful she sometimes couldn't sleep. Despite repeated surgery, antibiotics, steroids and other treatments, nothing helped.
Then last year, she took part in a trial for a new gel aimed at chronic wounds.
"It was the answer to my prayers," said McPherson, 58, a real estate agent in Tulsa, Oklahoma. Within weeks, McPherson said the ulcer treated was completely healed. "I tried everything possible and this is the only thing that worked."
The gel used to treat McPherson was developed by a team led by David Becker, a professor of cell and developmental biology at University College London. The gel, named Nexagon, works by interrupting how cells communicate and prevents the production of a protein that blocks healing. That allows cells to move faster to the wound to begin healing it.
Though it has only been tested on about 100 people so far, experts say if it proves successful, the gel could have a major impact on treating chronic wounds, like leg or diabetes ulcers, and even common scrapes or injuries from accidents.
In most chronic wounds, Becker said there is an abnormal amount of a protein involved in inflammation.
To reduce its amount, Becker and colleagues made Nexagon from bits of DNA that can block the protein's production. "As that protein is turned off, cells move in to close the wound," Becker said. The gel is clear and has the consistency of toothpaste.
In an early study on leg ulcers, scientists at the company Becker co-founded to develop the gel found that after four weeks, the number of people with completely healed ulcers was five times higher in patients who got the gel versus those who didn't. The average leg ulcer takes up to six months to heal and 60 percent of patients get repeated ulcers.
Other experts said the gel appeared promising. "It looks like the gel has a good effect in getting the outer layer (of skin) to restore itself," said Phil Stephens, head of tissue engineering and repair at Cardiff University. Stephens is not linked to Becker's research.
Care in Pennsylvania. Serena has no financial ties to Nexagon, but is one of the primary investigators for a U.S. trial of the product.
Another study is planned soon which experts said should answer more questions like the right dosage of the gel and any side effects.
In the U.S., there are 70 million people with chronic wounds. With increasing rates of obesity, experts predict there will soon be many more people suffering from diabetic ulcers.
Other gels are on the market, but don't work for everyone. Bioengineered skin, a protein that regulates cell growth and division, and even maggots are among the few other treatments that have been found to speed up healing.
Brad Duft, president of CoDa Therapeutics, which is developing the new gel, would not say how much Nexagon currently costs to make, for proprietary reasons.
He said the gel is still a couple of years away from being on the market and the price will drop significantly when that happens. Some leg ulcer patients spend about $30,000 a year or more on treatment. Duft said the new gel would cost a fraction of that.
For McPherson, the experience of being treated with Nexagon was so positive she asked to be included in the gel's next trial, to treat an even larger ulcer that wasn't eligible for the first study.
"To have something that works would change my life," she said.
LONDON — For three years, Connie McPherson had debilitating leg ulcers that were so painful she sometimes couldn't sleep. Despite repeated surgery, antibiotics, steroids and other treatments, nothing helped.
Then last year, she took part in a trial for a new gel aimed at chronic wounds.
"It was the answer to my prayers," said McPherson, 58, a real estate agent in Tulsa, Oklahoma. Within weeks, McPherson said the ulcer treated was completely healed. "I tried everything possible and this is the only thing that worked."
The gel used to treat McPherson was developed by a team led by David Becker, a professor of cell and developmental biology at University College London. The gel, named Nexagon, works by interrupting how cells communicate and prevents the production of a protein that blocks healing. That allows cells to move faster to the wound to begin healing it.
Though it has only been tested on about 100 people so far, experts say if it proves successful, the gel could have a major impact on treating chronic wounds, like leg or diabetes ulcers, and even common scrapes or injuries from accidents.
In most chronic wounds, Becker said there is an abnormal amount of a protein involved in inflammation.
To reduce its amount, Becker and colleagues made Nexagon from bits of DNA that can block the protein's production. "As that protein is turned off, cells move in to close the wound," Becker said. The gel is clear and has the consistency of toothpaste.
In an early study on leg ulcers, scientists at the company Becker co-founded to develop the gel found that after four weeks, the number of people with completely healed ulcers was five times higher in patients who got the gel versus those who didn't. The average leg ulcer takes up to six months to heal and 60 percent of patients get repeated ulcers.
Other experts said the gel appeared promising. "It looks like the gel has a good effect in getting the outer layer (of skin) to restore itself," said Phil Stephens, head of tissue engineering and repair at Cardiff University. Stephens is not linked to Becker's research.
Care in Pennsylvania. Serena has no financial ties to Nexagon, but is one of the primary investigators for a U.S. trial of the product.
Another study is planned soon which experts said should answer more questions like the right dosage of the gel and any side effects.
In the U.S., there are 70 million people with chronic wounds. With increasing rates of obesity, experts predict there will soon be many more people suffering from diabetic ulcers.
Other gels are on the market, but don't work for everyone. Bioengineered skin, a protein that regulates cell growth and division, and even maggots are among the few other treatments that have been found to speed up healing.
Brad Duft, president of CoDa Therapeutics, which is developing the new gel, would not say how much Nexagon currently costs to make, for proprietary reasons.
He said the gel is still a couple of years away from being on the market and the price will drop significantly when that happens. Some leg ulcer patients spend about $30,000 a year or more on treatment. Duft said the new gel would cost a fraction of that.
For McPherson, the experience of being treated with Nexagon was so positive she asked to be included in the gel's next trial, to treat an even larger ulcer that wasn't eligible for the first study.
"To have something that works would change my life," she said.
Friday, October 8, 2010
Epilepsy drug valproic acid could help in retinitis pigmentosa, study finds
A small preliminary study has found that valproic acid--a drug already used to treat epileptic seizures, migraines and bipolar disorder--may halt or even reverse the loss of vision produced by retinitis pigmentosa, researchers said Thursday. A team from the University of Massachusetts Medical School in Worchester is now organizing a clinical trial to confirm its observations.
Retinitis pigmentosa, commonly known as RP, is a group of eye diseases marked by degeneration of the retina, the part of the eye that captures images, leading to loss of peripheral vision and night vision. At least 40 genes have been linked to the condition and the particular manifestation of the disease depends on which genes are involved. The only effective treatment involves high levels of vitamin A palmitate, which can slow the progression of the disorder but not halt it. About one in 4,000 people is affected by RP, with many going blind by the age of 40.
Virtually all forms of the disease are characterized by inflammation and cell death. Dr. Shalesh Kaushal, a professor of ophthalmology and cell biology at the university, reasoned that valproic acid, which is known to affect both conditions, might slow the progression of RP, and tissue culture experiments suggested that was the case.
Kaushal and his colleagues then treated seven patients with an early stage of RP with 500 to 750 milligrams of valproic acid per day over the course of two to six months. The team reported in the British Journal of Ophthalmology that vision improved in five of the patients even though they were at a stage when vision loss normally progressed rapidly.
Kaushal is now organizing a three-year, $2.1-million clinical trial of the approach to test it against a placebo. The trial will be funded by the Foundation Fighting Blindness and the National Neurovision Research Institute. The clinical trials will be easier that they would be with an experimental compound because the safety of the drug has already been demonstrated.
Thomas H. Maugh II / Los Angeles Times
Retinitis pigmentosa, commonly known as RP, is a group of eye diseases marked by degeneration of the retina, the part of the eye that captures images, leading to loss of peripheral vision and night vision. At least 40 genes have been linked to the condition and the particular manifestation of the disease depends on which genes are involved. The only effective treatment involves high levels of vitamin A palmitate, which can slow the progression of the disorder but not halt it. About one in 4,000 people is affected by RP, with many going blind by the age of 40.
Virtually all forms of the disease are characterized by inflammation and cell death. Dr. Shalesh Kaushal, a professor of ophthalmology and cell biology at the university, reasoned that valproic acid, which is known to affect both conditions, might slow the progression of RP, and tissue culture experiments suggested that was the case.
Kaushal and his colleagues then treated seven patients with an early stage of RP with 500 to 750 milligrams of valproic acid per day over the course of two to six months. The team reported in the British Journal of Ophthalmology that vision improved in five of the patients even though they were at a stage when vision loss normally progressed rapidly.
Kaushal is now organizing a three-year, $2.1-million clinical trial of the approach to test it against a placebo. The trial will be funded by the Foundation Fighting Blindness and the National Neurovision Research Institute. The clinical trials will be easier that they would be with an experimental compound because the safety of the drug has already been demonstrated.
Thomas H. Maugh II / Los Angeles Times
Friday, October 1, 2010
What's Lurking in Those Supplements?
Jeannine Stein
Los Angeles Times
August 3, 2010
Do you really know what's in the dietary supplements you're taking? Consumer Reports tells what might be in those pills and powders in a new report. They focus on the less-than-desirable ingredients that could be lurking in the supplements people often take as part of their diet and exercise regimen or for sexual enhancement.
Consumer Reports worked with experts from the independent research group Natural Medicines Comprehensive Database to identify 12 ingredients in supplements that may have potential health risks, possibly leading to problems with cardiovascular, kidney or liver health. Those ingredients are: aconite, bitter orange, chaparral, colloidal silver, coltsfoot, comfrey, country mallow, germanium, greater celandine, kava, lobelia, and yohimbe. Some of the ingredients, according to the report, have had a previous FDA warning.
The Food and Drug Administration is taken to task by the report for what they say is the agency's lack of oversight in making sure supplements are safe. The report also argues that the FDA has not fully used its limited authority granted by the Dietary Supplement Health and Education Act to ban supplement ingredients that may be dangerous.
"Supplements are marketed with very seductive and sometimes overblown sales pitches for increasing your performance in the bedroom, slimming down or boosting your athletic prowess," said Nancy Metcalf, senior program editor for Consumer Reports, in a news release. "And consumers are easily lulled into believing that supplements can do no harm because they're ‘natural.' However, some natural ingredients can be hazardous, and on top of that the FDA has repeatedly found hazardous ingredients, including synthetic prescription drugs, in supplements."
The FDA also got dinged for not inspecting Chinese factories where many of the raw materials for supplements originate.
Consumers are cautioned to check with their doctor or pharmacist before taking any supplements, to be especially careful with weight-loss, sexual-enhancement and strength-building supplements, not to overdo supplements and to report any symptoms or side effects to a physician. The "USP Verified" mark on products indicates that the manufacturer has had U.S. Pharmacopeia verify the ingredients. USP is a nonprofit, private company that sets standards for prescription and over the counter medication and healthcare products manufactured or sold in the U.S.
The report also suggests not believing everything you hear or read about a product. "If a claim sounds too good to be true," it says, "it probably is."
Los Angeles Times
August 3, 2010
Do you really know what's in the dietary supplements you're taking? Consumer Reports tells what might be in those pills and powders in a new report. They focus on the less-than-desirable ingredients that could be lurking in the supplements people often take as part of their diet and exercise regimen or for sexual enhancement.
Consumer Reports worked with experts from the independent research group Natural Medicines Comprehensive Database to identify 12 ingredients in supplements that may have potential health risks, possibly leading to problems with cardiovascular, kidney or liver health. Those ingredients are: aconite, bitter orange, chaparral, colloidal silver, coltsfoot, comfrey, country mallow, germanium, greater celandine, kava, lobelia, and yohimbe. Some of the ingredients, according to the report, have had a previous FDA warning.
The Food and Drug Administration is taken to task by the report for what they say is the agency's lack of oversight in making sure supplements are safe. The report also argues that the FDA has not fully used its limited authority granted by the Dietary Supplement Health and Education Act to ban supplement ingredients that may be dangerous.
"Supplements are marketed with very seductive and sometimes overblown sales pitches for increasing your performance in the bedroom, slimming down or boosting your athletic prowess," said Nancy Metcalf, senior program editor for Consumer Reports, in a news release. "And consumers are easily lulled into believing that supplements can do no harm because they're ‘natural.' However, some natural ingredients can be hazardous, and on top of that the FDA has repeatedly found hazardous ingredients, including synthetic prescription drugs, in supplements."
The FDA also got dinged for not inspecting Chinese factories where many of the raw materials for supplements originate.
Consumers are cautioned to check with their doctor or pharmacist before taking any supplements, to be especially careful with weight-loss, sexual-enhancement and strength-building supplements, not to overdo supplements and to report any symptoms or side effects to a physician. The "USP Verified" mark on products indicates that the manufacturer has had U.S. Pharmacopeia verify the ingredients. USP is a nonprofit, private company that sets standards for prescription and over the counter medication and healthcare products manufactured or sold in the U.S.
The report also suggests not believing everything you hear or read about a product. "If a claim sounds too good to be true," it says, "it probably is."
Thursday, September 23, 2010
VisionCare's eye telescope wins approval
By Steve Johnson
sjohnson@mercurynews.com
Posted: 07/06/2010 09:16:55 PM PDT
Updated: 07/07/2010 08:32:51 AM PDT
In a decision cheered by advocates for the visually impaired, federal regulators Tuesday approved a Saratoga company's first-of-a-kind implantable eye telescope for elderly people with an advanced form of age-related macular degeneration.
The device made by VisionCare Ophthalmic Technologies is aimed at about 750,000 people in the United States who have the most severe and untreatable form of the disease, which causes a blind spot in the center of their vision.
"This innovation has the potential to provide many people with an improved quality of life," said Dr. Jeffrey Shuren, director of the Center for Devices and Radiological Health at the U.S. Food and Drug Administration, which approved VisionCare's device.
Getting the FDA's approval is a big moment for privately held VisionCare, which has been developing the telescope for more than a decade. In 2006, an FDA advisory panel recommended the telescope not be approved because of concerns about its usefulness and safety. But after VisionCare did more studies, the panel unanimously gave the device its blessing.
Although VisionCare has raised $59 million since it was founded in 1997, it has no other products on the market and has consistently lost money. Now the company is planning to roughly double its work force of 23, and "we hope to turn a profit after we launch the product," said Chet Kumar, VisionCare's
vice president for business and market development.
Even though most of the approximately 8 million people suffering from the disease in this country won't qualify to be treated with the device, advocates for patients suffering from the ailment hailed the FDA's approval.
"It's very exciting," said Dan Roberts, founding director of Macular Degeneration Support, a group he founded after he was diagnosed with the illness. "The product needs to be given a chance — anything that is going to give the patients better sight until we have a cure, anything that's going to give hope."
Dziem Nguyen, a supervisor at the Santa Clara Valley Blind Center, also was enthusiastic.
Noting that most of the center's patients suffer from age-related macular degeneration, she called the FDA's action "really good news to our folks here."
The ailment, which primarily afflicts the elderly, damages the center of the retina — or macula — which is the light-sensitive tissue at the back of the eye. The result is deteriorated sight in the center of the visual field, causing blurriness and eventually an inability to recognize faces, read or watch television.
The FDA limited VisionCare's telescope to people 75 or older, whose disease has progressed to a severe state. The device — which is about the size of a pea — is implanted in an outpatient procedure behind the colored portion of the eye known as the iris after the patient's own lens is removed.
By magnifying vision by 2.2 times to 2.7 times, depending on which model is used, the device projects visual images away from the damaged macula and onto the surrounding healthy retinal tissue. It is placed in only one eye, since the patient's other eye is needed for peripheral vision.
In a study involving more than 200 patients implanted with the device, the FDA said, 75 percent "improved their level of vision from severe or profound impairment to moderate impairment."
Although the device is approved for people with advanced wet or dry age-related macular degeneration, patients need to consult with a specialist and be tested to determine whether they are good candidates for the surgery.
In some cases, the implantation can distort the cornea's clarity, the FDA said. As a result, the federal agency is requiring VisionCare to conduct follow-up studies on patents outfitted with the telescope.
Kumar said the company has not set a price for the device because that will depend on how much Medicare will agree to cover. When those details are worked out over the next couple of months, patients can start getting implanted with the telescope, he said, noting that details about when the device will be available will be posted on www.centrasight.com.
Friday, September 17, 2010
What Big Eyes You Have, Dear, but Are Those Contacts Risky?
From the New York Times.
By CATHERINE SAINT LOUIS
Published: July 3, 2010
Of all the strange outfits and accessories Lady Gaga wore in her “Bad Romance” video, who would have guessed that the look that would catch fire would be the huge anime-style eyes she flashed in the bathtub?
Lady Gaga’s wider-than-life eyes were most likely generated by a computer, but teenagers and young women nationwide have been copying them with special contact lenses imported from Asia. Known as circle lenses, these are colored contacts — sometimes in weird shades like violet and pink — that make the eyes appear larger because they cover not just the iris, as normal lenses do, but also part of the whites.
“I’ve noticed a lot of girls in my town have started to wear them a lot,” said Melody Vue, a 16-year-old in Morganton, N.C., who owns 22 pairs and wears them regularly. She said her friends tended to wear circle lenses for their Facebook photos.
These lenses might be just another beauty fad if not for the facts that they are contraband and that eye doctors express grave concern over them. It is illegal in the United States to sell any contact lenses — corrective or cosmetic — without a prescription, and no major maker of contact lenses in the United States currently sells circle lenses.
Yet the lenses are widely available online, typically for $20 to $30 a pair, both in prescription strengths and purely decorative. On message boards and in YouTube videos, young women and teenage girls have been spreading the word about where to buy them.
The lenses give wearers a childlike, doe-eyed appearance. The look is characteristic of Japanese anime and is also popular in Korea. Fame-seekers there called “ulzzang girls” post cute but sexy head shots of themselves online, nearly always wearing circle lenses to accentuate their eyes. (“Ulzzang” means “best face” in Korean, but it is also shorthand for “pretty.”)
Now that circle lenses have gone mainstream in Japan, Singapore and South Korea, they are turning up in American high schools and on college campuses. “In the past year, there’s been a sharp increase in interest here in the U.S.,” said Joyce Kim, a founder of Soompi.com, an Asian pop fan site with a forum devoted to circle lenses. “Once early adopters have adequately posted about it, discussed it and reviewed them, it’s now available to everyone.”
Ms. Kim, who lives in San Francisco and is 31, said that some friends her age wear circle lenses almost every day. “It’s like wearing mascara or eyeliner,” she said.
Sites that sell contact lenses approved by the Food and Drug Administration are supposed to verify customers’ prescriptions with their eye doctors. By contrast, circle lens Web sites allow customers to choose the strength of their lenses as freely as their color.
Kristin Rowland, a college senior from Shirley, N.Y., has several pairs of circle lenses, including purple ones that are prescription strength and lime green ones that she wears behind her glasses. Without them, she said, her eyes look “really tiny”; the lenses “make them look like they exist.”
Ms. Rowland has a part-time job at a Waldbaum’s supermarket, where customers sometimes tell her, “Your eyes look huge today,” she said. Even her manager expressed curiosity, asking, “Where did you get those things?” she said.
Karen Riley, a spokeswoman for the F.D.A., was a bit surprised, too. When first contacted last month, she did not know what circle lenses were or the extent to which they had caught on. Soon after, she wrote in an e-mail message, “Consumers risk significant eye injuries — even blindness” when they buy contact lenses without a valid prescription or help from an eye professional.
Dr. S. Barry Eiden, an optometrist in Deerfield, Ill., who is chairman of the contact lens and cornea section of the American Optometric Association, said that people selling circle lenses online “are encouraging the avoidance of professional care.” He warned that ill-fitting contact lenses could deprive the eye of oxygen and cause serious vision problems.
Nina Nguyen, a 19-year-old Rutgers student from Bridgewater, N.J., said she was wary at first. “Our eyes are precious,” she said. “I wasn’t going to put any type of thing in my eyes.”
But after she saw how many students at Rutgers had circle lenses — and the groundswell of users online — she relented. Now she describes herself as “a circle lens addict.”
“What made me comfortable is so many girls out there wearing them,” Ms. Nguyen said.
A makeup artist named Michelle Phan introduced many Americans to circle lenses through a video tutorial on YouTube, where she demonstrates how to get “crazy, googly Lady Gaga eyes.” Ms. Phan’s video, called “Lady Gaga Bad Romance Look,” has been viewed more than 9.4 million times.
“In Asia, it’s all about the eyes in makeup,” said Ms. Phan, a Vietnamese-American blogger who is now Lancôme’s first video makeup artist. “They like the whole innocent doll-like look, almost like anime.”
These days girls of many races are embracing the look. “Circle lenses are not just for Asian people,” said Crystal Ezeoke, 17, a second-generation Nigerian from Lewisville, Tex. In videos she posts to YouTube, Ms. Ezeoke’s gray lenses make her eyes look an otherworldly blue.
At Lenscircle.com, which is based in Toronto, most of the customers are Americans, ages 15 to 25, who heard about circle lenses through YouTube reviewers, said Alfred Wong, 25, the site’s founder. “A lot of people like the dolly-eyed look, because it’s cute,” he said. “It’s still an emerging trend” in America, he added, but “it’s getting more and more popular.”
Jason Aw, an owner of PinkyParadise.com, a site based in Malaysia, is well aware that his shipments to the United States are illegal. But he is convinced that his circle lenses are “safe; that is why a lot of customers will recommend” them to others.
His “job,” he wrote in an e-mail message, is “to provide a platform” for people who want to buy the lenses but cannot do so locally.
Girls like Ms. Vue, the 16-year-old in North Carolina, help steer customers to sites where circle lenses are sold. She has posted 13 reviews of circle lenses on YouTube, enough to merit her a coupon code at tokioshine.com, which gives her viewers 10 percent off. “I have been getting tons of messages asking where to get circle lenses, so this is finally a legitimate answer for you,” she said in a recent video.
Ms. Vue was 14 when she begged her parents to get her first pair, she said. These days, however, she is having second thoughts about them — but not for health or safety reasons.
Circle lenses have just grown too popular, Ms. Vue said. “It kind of makes me not want to wear them anymore, because everyone is wearing them,” she said.
Wednesday, September 8, 2010
Study: The secret to long life is having the right genes
By Elizabeth Weise, USA TODAY
People who live to 100 and beyond have a unique set of genetic variations that seems to help them live 20 years longer than the rest of the population, researchers have found.
The gene clusters seem to trump disease-causing genes that would otherwise cause common problems of aging. Winning this genetic lottery, though, is no free pass: Exercise and healthy living still play a big role, scientists say.
The paper, in Thursday's online version of the journal Science, describes how scientists scanned the genomes of more than 1,000 centenarians, all Caucasians, from the New England Centenarian Study and found a cluster of 150 genetic markers that are highly predictive of extreme long life.
The older a subject got, the "stronger and stronger the correlation," says Thomas Perls, a professor of medicine at the Boston University School of Medicine and senior author on the paper.
Scientists have always known that long life runs in families, but this is the first time they have had proof that it's a genetic trait. Looking at his or her genes, "we can predict with about 77% accuracy" the probability of a person living to 100, Perls says.
There isn't a publicly available genetic test for this cluster of genes, though Perls says someone probably will start selling one soon. A good surrogate is to look at how long people in your family live.
Genes clearly don't tell the whole story: 23% of those who lived to be 100 or older didn't have the particular set of variants, the researcher found.
What they also don't yet know is what the genes actually are doing to make people live longer.
The study found that centenarians can be divided into 19 different groups of "genetic signatures" that correlate with different patterns of exceptional longevity. "Some signatures correlate with longer survival, others with the most delayed onset of age-related disease such as dementia ... or hypertension," says Paola Sebastiani, a biostatistician at Boston University and lead author on the paper.
The good news, Perls says, is that most humans have genetic variations "to allow us to get to 88, which is eight years longer than average." The catch: To achieve that age, he says, you still have to live a healthy life — exercise, avoid obesity, don't smoke, don't drink too much.
People who live to 100 and beyond have a unique set of genetic variations that seems to help them live 20 years longer than the rest of the population, researchers have found.
The gene clusters seem to trump disease-causing genes that would otherwise cause common problems of aging. Winning this genetic lottery, though, is no free pass: Exercise and healthy living still play a big role, scientists say.
The paper, in Thursday's online version of the journal Science, describes how scientists scanned the genomes of more than 1,000 centenarians, all Caucasians, from the New England Centenarian Study and found a cluster of 150 genetic markers that are highly predictive of extreme long life.
The older a subject got, the "stronger and stronger the correlation," says Thomas Perls, a professor of medicine at the Boston University School of Medicine and senior author on the paper.
Scientists have always known that long life runs in families, but this is the first time they have had proof that it's a genetic trait. Looking at his or her genes, "we can predict with about 77% accuracy" the probability of a person living to 100, Perls says.
There isn't a publicly available genetic test for this cluster of genes, though Perls says someone probably will start selling one soon. A good surrogate is to look at how long people in your family live.
Genes clearly don't tell the whole story: 23% of those who lived to be 100 or older didn't have the particular set of variants, the researcher found.
What they also don't yet know is what the genes actually are doing to make people live longer.
The study found that centenarians can be divided into 19 different groups of "genetic signatures" that correlate with different patterns of exceptional longevity. "Some signatures correlate with longer survival, others with the most delayed onset of age-related disease such as dementia ... or hypertension," says Paola Sebastiani, a biostatistician at Boston University and lead author on the paper.
The good news, Perls says, is that most humans have genetic variations "to allow us to get to 88, which is eight years longer than average." The catch: To achieve that age, he says, you still have to live a healthy life — exercise, avoid obesity, don't smoke, don't drink too much.
Saturday, September 4, 2010
Study: The secret to long life is having the right genes
By Elizabeth Weise, USA TODAY
People who live to 100 and beyond have a unique set of genetic variations that seems to help them live 20 years longer than the rest of the population, researchers have found.
The gene clusters seem to trump disease-causing genes that would otherwise cause common problems of aging. Winning this genetic lottery, though, is no free pass: Exercise and healthy living still play a big role, scientists say.
The paper, in Thursday's online version of the journal Science, describes how scientists scanned the genomes of more than 1,000 centenarians, all Caucasians, from the New England Centenarian Study and found a cluster of 150 genetic markers that are highly predictive of extreme long life.
The older a subject got, the "stronger and stronger the correlation," says Thomas Perls, a professor of medicine at the Boston University School of Medicine and senior author on the paper.
Scientists have always known that long life runs in families, but this is the first time they have had proof that it's a genetic trait. Looking at his or her genes, "we can predict with about 77% accuracy" the probability of a person living to 100, Perls says.
There isn't a publicly available genetic test for this cluster of genes, though Perls says someone probably will start selling one soon. A good surrogate is to look at how long people in your family live.
Genes clearly don't tell the whole story: 23% of those who lived to be 100 or older didn't have the particular set of variants, the researcher found.
What they also don't yet know is what the genes actually are doing to make people live longer.
The study found that centenarians can be divided into 19 different groups of "genetic signatures" that correlate with different patterns of exceptional longevity. "Some signatures correlate with longer survival, others with the most delayed onset of age-related disease such as dementia ... or hypertension," says Paola Sebastiani, a biostatistician at Boston University and lead author on the paper.
The good news, Perls says, is that most humans have genetic variations "to allow us to get to 88, which is eight years longer than average." The catch: To achieve that age, he says, you still have to live a healthy life — exercise, avoid obesity, don't smoke, don't drink too much.
People who live to 100 and beyond have a unique set of genetic variations that seems to help them live 20 years longer than the rest of the population, researchers have found.
The gene clusters seem to trump disease-causing genes that would otherwise cause common problems of aging. Winning this genetic lottery, though, is no free pass: Exercise and healthy living still play a big role, scientists say.
The paper, in Thursday's online version of the journal Science, describes how scientists scanned the genomes of more than 1,000 centenarians, all Caucasians, from the New England Centenarian Study and found a cluster of 150 genetic markers that are highly predictive of extreme long life.
The older a subject got, the "stronger and stronger the correlation," says Thomas Perls, a professor of medicine at the Boston University School of Medicine and senior author on the paper.
Scientists have always known that long life runs in families, but this is the first time they have had proof that it's a genetic trait. Looking at his or her genes, "we can predict with about 77% accuracy" the probability of a person living to 100, Perls says.
There isn't a publicly available genetic test for this cluster of genes, though Perls says someone probably will start selling one soon. A good surrogate is to look at how long people in your family live.
Genes clearly don't tell the whole story: 23% of those who lived to be 100 or older didn't have the particular set of variants, the researcher found.
What they also don't yet know is what the genes actually are doing to make people live longer.
The study found that centenarians can be divided into 19 different groups of "genetic signatures" that correlate with different patterns of exceptional longevity. "Some signatures correlate with longer survival, others with the most delayed onset of age-related disease such as dementia ... or hypertension," says Paola Sebastiani, a biostatistician at Boston University and lead author on the paper.
The good news, Perls says, is that most humans have genetic variations "to allow us to get to 88, which is eight years longer than average." The catch: To achieve that age, he says, you still have to live a healthy life — exercise, avoid obesity, don't smoke, don't drink too much.
Friday, August 27, 2010
Diet, Meds and Smoking Linked to Eye Disease Risks
Good nutrition staved off cataracts; some drugs, smoking increased vision problems, studies found
MONDAY, June 14 (HealthDay News) -- A healthy diet helps guard against cataracts, while certain medications raise the risks of this common cause of vision loss, two new studies suggest.
And a third study finds that smoking increases the risk of age-related macular degeneration, another disease that robs people of their sight.
The first study found that women who eat foods that contain high levels of a variety of vitamins and minerals may be less likely to develop nuclear cataract, which is the most common type of age-related cataract in the United States.
The study is published in the June issue of the Archives of Ophthalmology.
The researchers looked at 1,808 women in Iowa, Oregon and Wisconsin who took part in a study about age-related eye disease. Overall, 736 (41 percent) of the women had either nuclear cataracts evident from lens photographs or reported having undergone cataract extraction.
"Results from this study indicate that healthy diets, which reflect adherence to the U.S. dietary guidelines . . . are more strongly related to the lower occurrence of nuclear cataracts than any other modifiable risk factor or protective factor studied in this sample of women," Julie A. Mares, of the University of Wisconsin, Madison, and colleagues said in a news release from the journal.
The second study found that medications that increase sensitivity to the sun -- including antidepressants, diuretics, antibiotics and the pain reliever naproxen sodium (commonly sold over-the-counter as Aleve) -- increase the risk of age-related cataract.
Researchers followed-up with 4,926 participants over a 15-year period and concluded that an interaction between sun-sensitizing medications and sunlight (ultraviolet-B) exposure was associated with the development of cortical cataract.
"The medications [active ingredients] represent a broad range of chemical compounds, and the specific mechanism for the interaction is unclear," Dr. Barbara E.K. Klein and colleagues at the University of Wisconsin, Madison, said in the news release. Their report was released online in advance of publication in the August print issue of the Archives of Ophthalmology.
Because the lens of the eye develops from the same tissue layer as the skin, sun-sensitizing medications may affect the eyes as well as the skin, the researchers explained.
"Our results need to be evaluated in other populations, especially in view of the increasing frequency of sun-sensitizing medications," they concluded. "If our findings are confirmed, it would be important to examine whether the effect is greater in those with higher levels of ambient sunlight (UV-B) exposure and if dose or duration of medication use is also important."
The third study, also published online and in the August print issue of Archives of Ophthalmology, found that smoking and cholesterol levels affect the risk for early-stage age-related macular degeneration (AMD).
AMD is uncommon before age 55 but the risk increases after that age, therefore most studies focus on AMD in middle-aged and older adults, according to background information in the report.
"To our knowledge, accurate estimates of prevalence of AMD among adults younger than 40 years are lacking. Such information is important for understanding the relationships of risk factors to AMD across the age spectrum and for identifying factors that might affect this disease earlier in life," Dr. Ronald Klein, of the University of Wisconsin, Madison, and colleagues said in the news release.
The study included 2,810 people, aged 21 to 84, who were assessed for the presence and severity of drusen. These yellow or white deposits in the retina are an early sign of AMD.
Overall, early AMD was detected in 3.4 percent of the participants, with rates ranging from 2.4 percent among those aged 21 to 34 to 9.8 percent for those aged 65 and older. Besides age, additional risk factors associated with increased risk for AMD included being male, heavy smoking for a long period of time, and being hearing impaired. Elevated levels of HDL ("good") cholesterol were associated with a lower risk for AMD, the study authors noted.
The findings "demonstrate that early AMD onset may occur in midlife. Some modifiable factors [smoking status and serum HDL cholesterol level] associated with AMD in older cohorts were associated with early AMD in this cohort of middle-aged adults," the researchers concluded.
MONDAY, June 14 (HealthDay News) -- A healthy diet helps guard against cataracts, while certain medications raise the risks of this common cause of vision loss, two new studies suggest.
And a third study finds that smoking increases the risk of age-related macular degeneration, another disease that robs people of their sight.
The first study found that women who eat foods that contain high levels of a variety of vitamins and minerals may be less likely to develop nuclear cataract, which is the most common type of age-related cataract in the United States.
The study is published in the June issue of the Archives of Ophthalmology.
The researchers looked at 1,808 women in Iowa, Oregon and Wisconsin who took part in a study about age-related eye disease. Overall, 736 (41 percent) of the women had either nuclear cataracts evident from lens photographs or reported having undergone cataract extraction.
"Results from this study indicate that healthy diets, which reflect adherence to the U.S. dietary guidelines . . . are more strongly related to the lower occurrence of nuclear cataracts than any other modifiable risk factor or protective factor studied in this sample of women," Julie A. Mares, of the University of Wisconsin, Madison, and colleagues said in a news release from the journal.
The second study found that medications that increase sensitivity to the sun -- including antidepressants, diuretics, antibiotics and the pain reliever naproxen sodium (commonly sold over-the-counter as Aleve) -- increase the risk of age-related cataract.
Researchers followed-up with 4,926 participants over a 15-year period and concluded that an interaction between sun-sensitizing medications and sunlight (ultraviolet-B) exposure was associated with the development of cortical cataract.
"The medications [active ingredients] represent a broad range of chemical compounds, and the specific mechanism for the interaction is unclear," Dr. Barbara E.K. Klein and colleagues at the University of Wisconsin, Madison, said in the news release. Their report was released online in advance of publication in the August print issue of the Archives of Ophthalmology.
Because the lens of the eye develops from the same tissue layer as the skin, sun-sensitizing medications may affect the eyes as well as the skin, the researchers explained.
"Our results need to be evaluated in other populations, especially in view of the increasing frequency of sun-sensitizing medications," they concluded. "If our findings are confirmed, it would be important to examine whether the effect is greater in those with higher levels of ambient sunlight (UV-B) exposure and if dose or duration of medication use is also important."
The third study, also published online and in the August print issue of Archives of Ophthalmology, found that smoking and cholesterol levels affect the risk for early-stage age-related macular degeneration (AMD).
AMD is uncommon before age 55 but the risk increases after that age, therefore most studies focus on AMD in middle-aged and older adults, according to background information in the report.
"To our knowledge, accurate estimates of prevalence of AMD among adults younger than 40 years are lacking. Such information is important for understanding the relationships of risk factors to AMD across the age spectrum and for identifying factors that might affect this disease earlier in life," Dr. Ronald Klein, of the University of Wisconsin, Madison, and colleagues said in the news release.
The study included 2,810 people, aged 21 to 84, who were assessed for the presence and severity of drusen. These yellow or white deposits in the retina are an early sign of AMD.
Overall, early AMD was detected in 3.4 percent of the participants, with rates ranging from 2.4 percent among those aged 21 to 34 to 9.8 percent for those aged 65 and older. Besides age, additional risk factors associated with increased risk for AMD included being male, heavy smoking for a long period of time, and being hearing impaired. Elevated levels of HDL ("good") cholesterol were associated with a lower risk for AMD, the study authors noted.
The findings "demonstrate that early AMD onset may occur in midlife. Some modifiable factors [smoking status and serum HDL cholesterol level] associated with AMD in older cohorts were associated with early AMD in this cohort of middle-aged adults," the researchers concluded.
Friday, August 20, 2010
Retina Transplants from Stem Cells
Human embryonic stem cells can be coaxed into three-dimensional structures of retinal cells.
By Courtney Humphries
From Technology Review (published by MIT)
Scientists have created a three-dimensional, retina-like structure out of human embryonic stem cells that they hope could someday serve as a retinal transplant for people with macular degeneration and other diseases of the retina. Their method, published recently in Journal of Neuroscience Methods, offers a potential new source of cells for retinal transplants.
Hans Keirstead, lead author of the paper and a stem cell biologist at University of California, Irvine, says that the method is designed to provide an alternative to human fetal tissue transplants, which have been conducted on a small group of patients and have resulted in improved vision. Fetal cells are difficult to obtain and raise ethical issues. "We really wanted to build upon that technique by creating a renewable source of tissue," he says.
In this study, the researchers first created two types of cells from the human embryonic stem cells: early-stage retinal cells, and retinal pigment epithelium (RPE) cells, which provide nourishment to the cells responsible for vision in the retina. The researchers then grew these two types of cells together in a chamber designed to expose them to a gradient of concentrations of solutes and growth-promoting chemicals. The cells could form three-dimensional structures, a feat rarely achieved with stem cells.
Keirstead believes that the study points to two important strategies for creating retinal transplants: growing early retinal cells along with RPE cells, and bathing the cells in a gradually changing solution that encourages the development of three-dimensional layers of cells. His team found that this approach generated early-stage retinal cells that were on the path of differentiating into all of the various cell types in the retina.
Keirstead believes that a retinal transplant will work best when made of cells that have not fully developed. "The three-dimensional layer is purposefully young," he says. Previous studies have found that younger cells are more likely to integrate with existing tissue after transplantation, rather than die.
Robert Lanza, chief scientific officer at Advanced Cell Technologies, who was not involved in the study, says that his team discovered several years ago that, when turning human embryonic stem cells into RPE cells, other stem cells would spontaneously form layers, including patches of photoreceptors. "This paper shows that you can take advantage of this natural process, and for the first time use tissue engineering techniques to generate three-dimensional retina-like structures," he says.
But Lanza is skeptical about the clinical usefulness of such structures. "You can't just transplant a retina and restore sight," he says, because it requires making a series of complex connections with the brain. Although he says there could prove to be some advantage to using three constructs of cells, "for the moment, replacing individual cell types might be the best approach for helping patients suffering from eye disease."
Scientists have been working on several approaches to retinal transplants. One approach, led by Advanced Cell Technologies, is to turn human embryonic stem cells into RPE cells and transplant them into the retina. The therapy would work best in the early stages of degeneration to halt further progress, rather than to restore vision that is already lost. Another approach is to transplant stem cells that are in the early stages of becoming light-sensitive photoreceptors, which has demonstrated efficacy in mice.
Yet another strategy is to use young tissue instead of individual cells. Fetal tissue transplants have shown some success in animals as well as a small group of humans. A study published in 2008 found that seven out of 10 patients who received the transplants had improved vision. However, there has been debate about whether these transplants actually integrate into the existing tissue. Keirstead has conducted a series of studies in animals that he says demonstrates that transplanted tissue is functioning in the eye. If so, the strategy could be useful for later-stage degeneration, when the existing retina has lost much of its function.
For Keirstead's team, the next step is to show that tissue derived from stem cells can function properly. His lab is currently transplanting the tissue into rats to determine whether the transplants can survive and incorporate into the eye, and whether they improve the animals' vision.
By Courtney Humphries
From Technology Review (published by MIT)
Scientists have created a three-dimensional, retina-like structure out of human embryonic stem cells that they hope could someday serve as a retinal transplant for people with macular degeneration and other diseases of the retina. Their method, published recently in Journal of Neuroscience Methods, offers a potential new source of cells for retinal transplants.
Hans Keirstead, lead author of the paper and a stem cell biologist at University of California, Irvine, says that the method is designed to provide an alternative to human fetal tissue transplants, which have been conducted on a small group of patients and have resulted in improved vision. Fetal cells are difficult to obtain and raise ethical issues. "We really wanted to build upon that technique by creating a renewable source of tissue," he says.
In this study, the researchers first created two types of cells from the human embryonic stem cells: early-stage retinal cells, and retinal pigment epithelium (RPE) cells, which provide nourishment to the cells responsible for vision in the retina. The researchers then grew these two types of cells together in a chamber designed to expose them to a gradient of concentrations of solutes and growth-promoting chemicals. The cells could form three-dimensional structures, a feat rarely achieved with stem cells.
Keirstead believes that the study points to two important strategies for creating retinal transplants: growing early retinal cells along with RPE cells, and bathing the cells in a gradually changing solution that encourages the development of three-dimensional layers of cells. His team found that this approach generated early-stage retinal cells that were on the path of differentiating into all of the various cell types in the retina.
Keirstead believes that a retinal transplant will work best when made of cells that have not fully developed. "The three-dimensional layer is purposefully young," he says. Previous studies have found that younger cells are more likely to integrate with existing tissue after transplantation, rather than die.
Robert Lanza, chief scientific officer at Advanced Cell Technologies, who was not involved in the study, says that his team discovered several years ago that, when turning human embryonic stem cells into RPE cells, other stem cells would spontaneously form layers, including patches of photoreceptors. "This paper shows that you can take advantage of this natural process, and for the first time use tissue engineering techniques to generate three-dimensional retina-like structures," he says.
But Lanza is skeptical about the clinical usefulness of such structures. "You can't just transplant a retina and restore sight," he says, because it requires making a series of complex connections with the brain. Although he says there could prove to be some advantage to using three constructs of cells, "for the moment, replacing individual cell types might be the best approach for helping patients suffering from eye disease."
Scientists have been working on several approaches to retinal transplants. One approach, led by Advanced Cell Technologies, is to turn human embryonic stem cells into RPE cells and transplant them into the retina. The therapy would work best in the early stages of degeneration to halt further progress, rather than to restore vision that is already lost. Another approach is to transplant stem cells that are in the early stages of becoming light-sensitive photoreceptors, which has demonstrated efficacy in mice.
Yet another strategy is to use young tissue instead of individual cells. Fetal tissue transplants have shown some success in animals as well as a small group of humans. A study published in 2008 found that seven out of 10 patients who received the transplants had improved vision. However, there has been debate about whether these transplants actually integrate into the existing tissue. Keirstead has conducted a series of studies in animals that he says demonstrates that transplanted tissue is functioning in the eye. If so, the strategy could be useful for later-stage degeneration, when the existing retina has lost much of its function.
For Keirstead's team, the next step is to show that tissue derived from stem cells can function properly. His lab is currently transplanting the tissue into rats to determine whether the transplants can survive and incorporate into the eye, and whether they improve the animals' vision.
Friday, August 13, 2010
Researchers Say They Created a ‘Synthetic Cell’
By NICHOLAS WADE
Published: May 20, 2010
New York Times
The genome pioneer J. Craig Venter has taken another step in his quest to create synthetic life, by synthesizing an entire bacterial genome and using it to take over a cell.
Dr. Venter calls the result a “synthetic cell” and is presenting the research as a landmark achievement that will open the way to creating useful microbes from scratch to make products like vaccines and biofuels. At a press conference Thursday, Dr. Venter described the converted cell as “the first self-replicating species we’ve had on the planet whose parent is a computer.”
“This is a philosophical advance as much as a technical advance,” he said, suggesting that the “synthetic cell” raised new questions about the nature of life.
Other scientists agree that he has achieved a technical feat in synthesizing the largest piece of DNA so far — a million units in length — and in making it accurate enough to substitute for the cell’s own DNA.
But some regard this approach as unpromising because it will take years to design new organisms, and meanwhile progress toward making biofuels is already being achieved with conventional genetic engineering approaches in which existing organisms are modified a few genes at a time.
Dr. Venter’s aim is to achieve total control over a bacterium’s genome, first by synthesizing its DNA in a laboratory and then by designing a new genome stripped of many natural functions and equipped with new genes that govern production of useful chemicals.
“It’s very powerful to be able to reconstruct and own every letter in a genome because that means you can put in different genes,” said Gerald Joyce, a biologist at the Scripps Research Institute in La Jolla, Calif.
In response to the scientific report, President Obama asked the White House bioethics commission on Thursday to complete a study of the issues raised by synthetic biology within six months and report back to him on its findings. He said the new development raised “genuine concerns,” though he did not specify them further.
Dr. Venter took a first step toward this goal three years ago, showing that the natural DNA from one bacterium could be inserted into another and that it would take over the host cell’s operation. Last year, his team synthesized a piece of DNA with 1,080,000 bases, the chemical units of which DNA is composed.
In a final step, a team led by Daniel G. Gibson, Hamilton O. Smith and Dr. Venter report in Thursday’s issue of the journal Science that the synthetic DNA takes over a bacterial cell just as the natural DNA did, making the cell generate the proteins specified by the new DNA’s genetic information in preference to those of its own genome.
The team ordered pieces of DNA 1,000 units in length from Blue Heron, a company that specializes in synthesizing DNA, and developed a technique for assembling the shorter lengths into a complete genome. The cost of the project was $40 million, most of it paid for by Synthetic Genomics, a company Dr. Venter founded.
But the bacterium used by the Venter group is unsuitable for biofuel production, and Dr. Venter said he would move to different organisms. Synthetic Genomics has a contract from Exxon to generate biofuels from algae. Exxon is prepared to spend up to $600 million if all its milestones are met. Dr. Venter said he would try to build “an entire algae genome so we can vary the 50 to 60 different parameters for algae growth to make superproductive organisms.”
On his yacht trips round the world, Dr. Venter has analyzed the DNA of the many microbes in seawater and now has a library of about 40 million genes, mostly from algae. These genes will be a resource to make captive algae produce useful chemicals, he said.
Some other scientists said that aside from assembling a large piece of DNA, Dr. Venter has not broken new ground. “To my mind Craig has somewhat overplayed the importance of this,” said David Baltimore, a geneticist at Caltech. He described the result as “a technical tour de force,” a matter of scale rather than a scientific breakthrough.
“He has not created life, only mimicked it,” Dr. Baltimore said.
Dr. Venter’s approach “is not necessarily on the path” to produce useful microorganisms, said George Church, a genome researcher at Harvard Medical School. Leroy Hood, of the Institute for Systems Biology in Seattle, described Dr. Venter’s report as “glitzy” but said lower-level genes and networks had to be understood first before it would be worth trying to design whole organisms from scratch.
In 2002 Eckard Wimmer, of the State University of New York at Stony Brook, synthesized the genome of the polio virus. The genome constructed a live polio virus that infected and killed mice. Dr. Venter’s work on the bacterium is similar in principle, except that the polio virus genome is only 7,500 units in length, and the bacteria’s genome is more than 100 times longer.
Friends of the Earth, an environmental group, denounced the synthetic genome as “dangerous new technology,” saying that “Mr. Venter should stop all further research until sufficient regulations are in place.”
The genome Dr. Venter synthesized is copied from a natural bacterium that infects goats. He said that before copying the DNA, he excised 14 genes likely to be pathogenic, so the new bacterium, even if it escaped, would be unlikely to cause goats harm.
Dr. Venter’s assertion that he has created a “synthetic cell” has alarmed people who think that means he has created a new life form or an artificial cell. “Of course that’s not right — its ancestor is a biological life form,” said Dr. Joyce of Scripps.
Dr. Venter copied the DNA from one species of bacteria and inserted it into another. The second bacteria made all the proteins and organelles in the so-called “synthetic cell,” by following the specifications implicit in the structure of the inserted DNA.
“My worry is that some people are going to draw the conclusion that they have created a new life form,” said Jim Collins, a bioengineer at Boston University. “What they have created is an organism with a synthesized natural genome. But it doesn’t represent the creation of life from scratch or the creation of a new life form,” he said.
Published: May 20, 2010
New York Times
The genome pioneer J. Craig Venter has taken another step in his quest to create synthetic life, by synthesizing an entire bacterial genome and using it to take over a cell.
Dr. Venter calls the result a “synthetic cell” and is presenting the research as a landmark achievement that will open the way to creating useful microbes from scratch to make products like vaccines and biofuels. At a press conference Thursday, Dr. Venter described the converted cell as “the first self-replicating species we’ve had on the planet whose parent is a computer.”
“This is a philosophical advance as much as a technical advance,” he said, suggesting that the “synthetic cell” raised new questions about the nature of life.
Other scientists agree that he has achieved a technical feat in synthesizing the largest piece of DNA so far — a million units in length — and in making it accurate enough to substitute for the cell’s own DNA.
But some regard this approach as unpromising because it will take years to design new organisms, and meanwhile progress toward making biofuels is already being achieved with conventional genetic engineering approaches in which existing organisms are modified a few genes at a time.
Dr. Venter’s aim is to achieve total control over a bacterium’s genome, first by synthesizing its DNA in a laboratory and then by designing a new genome stripped of many natural functions and equipped with new genes that govern production of useful chemicals.
“It’s very powerful to be able to reconstruct and own every letter in a genome because that means you can put in different genes,” said Gerald Joyce, a biologist at the Scripps Research Institute in La Jolla, Calif.
In response to the scientific report, President Obama asked the White House bioethics commission on Thursday to complete a study of the issues raised by synthetic biology within six months and report back to him on its findings. He said the new development raised “genuine concerns,” though he did not specify them further.
Dr. Venter took a first step toward this goal three years ago, showing that the natural DNA from one bacterium could be inserted into another and that it would take over the host cell’s operation. Last year, his team synthesized a piece of DNA with 1,080,000 bases, the chemical units of which DNA is composed.
In a final step, a team led by Daniel G. Gibson, Hamilton O. Smith and Dr. Venter report in Thursday’s issue of the journal Science that the synthetic DNA takes over a bacterial cell just as the natural DNA did, making the cell generate the proteins specified by the new DNA’s genetic information in preference to those of its own genome.
The team ordered pieces of DNA 1,000 units in length from Blue Heron, a company that specializes in synthesizing DNA, and developed a technique for assembling the shorter lengths into a complete genome. The cost of the project was $40 million, most of it paid for by Synthetic Genomics, a company Dr. Venter founded.
But the bacterium used by the Venter group is unsuitable for biofuel production, and Dr. Venter said he would move to different organisms. Synthetic Genomics has a contract from Exxon to generate biofuels from algae. Exxon is prepared to spend up to $600 million if all its milestones are met. Dr. Venter said he would try to build “an entire algae genome so we can vary the 50 to 60 different parameters for algae growth to make superproductive organisms.”
On his yacht trips round the world, Dr. Venter has analyzed the DNA of the many microbes in seawater and now has a library of about 40 million genes, mostly from algae. These genes will be a resource to make captive algae produce useful chemicals, he said.
Some other scientists said that aside from assembling a large piece of DNA, Dr. Venter has not broken new ground. “To my mind Craig has somewhat overplayed the importance of this,” said David Baltimore, a geneticist at Caltech. He described the result as “a technical tour de force,” a matter of scale rather than a scientific breakthrough.
“He has not created life, only mimicked it,” Dr. Baltimore said.
Dr. Venter’s approach “is not necessarily on the path” to produce useful microorganisms, said George Church, a genome researcher at Harvard Medical School. Leroy Hood, of the Institute for Systems Biology in Seattle, described Dr. Venter’s report as “glitzy” but said lower-level genes and networks had to be understood first before it would be worth trying to design whole organisms from scratch.
In 2002 Eckard Wimmer, of the State University of New York at Stony Brook, synthesized the genome of the polio virus. The genome constructed a live polio virus that infected and killed mice. Dr. Venter’s work on the bacterium is similar in principle, except that the polio virus genome is only 7,500 units in length, and the bacteria’s genome is more than 100 times longer.
Friends of the Earth, an environmental group, denounced the synthetic genome as “dangerous new technology,” saying that “Mr. Venter should stop all further research until sufficient regulations are in place.”
The genome Dr. Venter synthesized is copied from a natural bacterium that infects goats. He said that before copying the DNA, he excised 14 genes likely to be pathogenic, so the new bacterium, even if it escaped, would be unlikely to cause goats harm.
Dr. Venter’s assertion that he has created a “synthetic cell” has alarmed people who think that means he has created a new life form or an artificial cell. “Of course that’s not right — its ancestor is a biological life form,” said Dr. Joyce of Scripps.
Dr. Venter copied the DNA from one species of bacteria and inserted it into another. The second bacteria made all the proteins and organelles in the so-called “synthetic cell,” by following the specifications implicit in the structure of the inserted DNA.
“My worry is that some people are going to draw the conclusion that they have created a new life form,” said Jim Collins, a bioengineer at Boston University. “What they have created is an organism with a synthesized natural genome. But it doesn’t represent the creation of life from scratch or the creation of a new life form,” he said.
Friday, July 30, 2010
Eating Nuts May Help Cholesterol Levels
By Ed Edelson
HealthDay Reporter
MONDAY, May 10 (HealthDay News) -- An analysis of studies has produced what its authors describe as a precise description of the beneficial effects of nut consumption on cholesterol and other heart-related fats.
It provides "the best evidence yet that eating nuts reduces LDL cholesterol and improves the blood lipids profile," said Dr. Joan Sabate, who chairs the nutrition department at the Loma Linda University School of Public Health in California and was a co-author of the report, published May 10 in Archives of Internal Medicine.
Sabate and fellow researchers at the university pooled data on 583 men and women who had participated in 25 nut consumption trials. The results showed that eating about 2.3 ounces of nuts a day -- a third of a cupful -- reduced total cholesterol levels by 5.1 percent and "bad" LDL cholesterol by 7.4 percent.
That amount of nut eating also improved the ratio of LDL cholesterol to "good" HDL cholesterol by 8.3 percent and caused a decrease of 10.2 percent in triglyceride levels among people with high levels of those blood fats.
Sabate is a leading figure in the somewhat limited field of nut nutrition. His first report on the beneficial effects, published in 1993, led to other studies that eventually prompted the U.S. Food and Drug Administration to issue a qualified health claim for nuts a decade later.
The 2003 FDA statement said that "scientific evidence suggests but does not prove that eating 1.5 ounces of most nuts per day, as part of a diet low in saturated fat and cholesterol, may reduce the risk of heart disease."
On food labels, that claim is followed by a caution: "See nutrition information for fat content."
The FDA statement was issued in response to a petition filed by the International Tree Nut Council Research and Education Foundation, which supports the work done by Sabate and other nut nutrition researchers. The foundation helped fund the latest report.
The new study found that the benefits from eating nuts was greatest among thin people, those with high LDL cholesterol and those consuming a fat-rich diet.
But enthusiasm for nuts should be restrained, Sabate said. They are highly caloric, and thus can contribute to obesity. A 3-ounce-a-day limit was recommended.
Jeannie Gazzaniga-Moloo, a spokeswoman for the American Dietetic Association who is in private practice in Sacramento, Calif., said that "nuts can be a very healthy addition to any diet," but she recommends eating somewhat less of them.
She said she suggests that her clients consume about an ounce a day of nuts -- about 22 walnuts, for example, providing about 150 calories -- as part of their daily diet. "They are rich in protein and dietary fiber as well as numerous proteins and in various vitamins," Gazzaniga-Moloo said.
"They should eat the nuts they enjoy," she said. "They can try a variety."
Sabata said that the type of nuts eaten doesn't seem to matter. The study found essentially the same results for walnuts, almonds, peanuts, pecans, hazelnuts, macadamias and pistachios.
"Nuts are a matrix of healthy nutrients, and the most obvious reason for the cholesterol-lowering effect is their unsaturated fat content," Sabate said. "Nuts also contain fiber, vegetable protein, phytoesterols and other antioxidants."
The best evidence for the beneficial effect of nuts, though, has come from studies of walnuts and almonds, he added.
HealthDay Reporter
MONDAY, May 10 (HealthDay News) -- An analysis of studies has produced what its authors describe as a precise description of the beneficial effects of nut consumption on cholesterol and other heart-related fats.
It provides "the best evidence yet that eating nuts reduces LDL cholesterol and improves the blood lipids profile," said Dr. Joan Sabate, who chairs the nutrition department at the Loma Linda University School of Public Health in California and was a co-author of the report, published May 10 in Archives of Internal Medicine.
Sabate and fellow researchers at the university pooled data on 583 men and women who had participated in 25 nut consumption trials. The results showed that eating about 2.3 ounces of nuts a day -- a third of a cupful -- reduced total cholesterol levels by 5.1 percent and "bad" LDL cholesterol by 7.4 percent.
That amount of nut eating also improved the ratio of LDL cholesterol to "good" HDL cholesterol by 8.3 percent and caused a decrease of 10.2 percent in triglyceride levels among people with high levels of those blood fats.
Sabate is a leading figure in the somewhat limited field of nut nutrition. His first report on the beneficial effects, published in 1993, led to other studies that eventually prompted the U.S. Food and Drug Administration to issue a qualified health claim for nuts a decade later.
The 2003 FDA statement said that "scientific evidence suggests but does not prove that eating 1.5 ounces of most nuts per day, as part of a diet low in saturated fat and cholesterol, may reduce the risk of heart disease."
On food labels, that claim is followed by a caution: "See nutrition information for fat content."
The FDA statement was issued in response to a petition filed by the International Tree Nut Council Research and Education Foundation, which supports the work done by Sabate and other nut nutrition researchers. The foundation helped fund the latest report.
The new study found that the benefits from eating nuts was greatest among thin people, those with high LDL cholesterol and those consuming a fat-rich diet.
But enthusiasm for nuts should be restrained, Sabate said. They are highly caloric, and thus can contribute to obesity. A 3-ounce-a-day limit was recommended.
Jeannie Gazzaniga-Moloo, a spokeswoman for the American Dietetic Association who is in private practice in Sacramento, Calif., said that "nuts can be a very healthy addition to any diet," but she recommends eating somewhat less of them.
She said she suggests that her clients consume about an ounce a day of nuts -- about 22 walnuts, for example, providing about 150 calories -- as part of their daily diet. "They are rich in protein and dietary fiber as well as numerous proteins and in various vitamins," Gazzaniga-Moloo said.
"They should eat the nuts they enjoy," she said. "They can try a variety."
Sabata said that the type of nuts eaten doesn't seem to matter. The study found essentially the same results for walnuts, almonds, peanuts, pecans, hazelnuts, macadamias and pistachios.
"Nuts are a matrix of healthy nutrients, and the most obvious reason for the cholesterol-lowering effect is their unsaturated fat content," Sabate said. "Nuts also contain fiber, vegetable protein, phytoesterols and other antioxidants."
The best evidence for the beneficial effect of nuts, though, has come from studies of walnuts and almonds, he added.
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