from Health Day. News for Healthier Living.
In study, athletes had 'younger' immune cells than sedentary, healthy adults
By Jennifer Thomas
HealthDay Reporter
MONDAY, Nov. 30 (HealthDay News) -- Studies have shown that exercise can help ward off heart disease and cancer, and now new research shows that the reason why may be found within cells themselves.
Endurance athletes had longer telomeres -- DNA at the tips of chromosomes that protect the cell -- in their white blood cells than healthy, nonsmoking adults who did not exercise regularly, German researchers report.
Telomeres can be thought of as the plastic tips on the end of shoelaces, which prevent the lace from fraying, explained Emmanuel Skordalakes, an assistant professor of gene expression and regulation at The Wistar Institute in Philadelphia.
Over the life span, cells continue to divide. Each time a cell divides, the telomere is shortened. When the telomere gets too short, the cell stops dividing. When this happens, people age -- gradually losing muscle strength, skin elasticity, vision, hearing and mental abilities, and so on, Skordalakes said.
In the study, the researchers measured the length of white blood cell telomeres of endurance athletes and compared them to the telomeres of age-matched healthy nonsmokers who typically exercised less than one hour a week (the control group). Athletic participants included professional runners with an average age of 20 who ran more than 45 miles a week as part of the German National track and field team. A second group of athletes were middle-aged (average age 51) who had done endurance exercise since youth and ran an average of nearly 50 miles a week.
Not surprisingly, the athletes had a slower resting heart rate -- a sign of cardiovascular fitness -- as well as lower blood pressure, lower body mass index and lower cholesterol than those in the control group.
But the athletes also had longer telomeres than those who were of similar age but did not exercise, and the athletes showed increased activity of the enzyme telomerase, which maintains the telomere.
"This is direct evidence of an anti-aging effect of physical exercise," study author Dr. Ulrich Laufs, a professor of clinical and experimental medicine in the department of internal medicine at Saarland University in Homburg, said in a statement.
The study findings were released online Nov. 30 in advance of publication in an upcoming print issue of Circulation.
Until recently, the primary role of white blood cells was thought to be fighting off infections, said Dr. Annabelle Volgman, a cardiologist and director of the Heart Center for Women at Rush University Medical Center in Chicago.
Newer research has shown white blood cells do much more, including continuously seeking out abnormal cell growths, such as those that cause cancer, and clearing them away.
One reason why cancer rates increase with age could be that the white blood cells themselves age, and become less efficient at dealing with the abnormal growths, Volgman said. If exercise maintains the youthfulness of the white blood cells by preventing the shortening of the telomere, it may explain why exercise can protect against developing cancer.
Likewise, with heart disease, aging white blood cells (along with high blood pressure and other factors) may allow plaques to accumulate more quickly. By keeping white blood cells young, exercise may enable them to continue to efficiently clear away plaques, Volgman said.
"We know that any physical activity improves cardiovascular health and helps in preventing cancer," Volgman said. "This study is showing us the molecular basis for this."
The question, of course, is how much exercise is needed to prevent telomere shortening. Must one be a marathon runner? Or is the standard advice of walking for at least 30 minutes, most days of the week enough?
Because no one really knows the answer, Volgman said, the best advice is to do some sort of exercise regularly. Previous research has shown even moderate activity can be beneficial to the telomeres.
Exercise intensity should be guided by fitness level -- in other words, if you're used to doing vigorous exercise, keep it up. If not, do what you can without overdoing it or risking other injury.
"Not everyone has the makeup to be an elite athlete," Volgman said. "The safest thing to say is that people do need that aerobic exercise. But there are so many factors that impact aging and if you are going to get cancer or heart disease."
In addition to testing human white blood cells, researchers also used mice to study the impact of exercise on proteins that have been implicated in heart disease and cancer. The researchers found that the mice with access to a running wheel for three weeks showed increased activity of tumor-suppressing proteins and proteins that play a role in telomere length.
"What these people have shown through this study is that through activity and a healthy lifestyle, you can upregulate the levels of activity of factors that protect or play a role in maintaining the telomeres of humans and mice," Skordalakes said.
More information
The American Academy of Family Physicians has tips for starting an exercise program.
SOURCES: Emmanuel Skordalakes, Ph.D., assistant professor, gene expression and regulation, The Wistar Institute, Philadelphia; Annabelle Volgman, M.D., cardiologist and director, Heart Center for Women, Rush University Medical Center, Chicago; Nov. 30, 2009, Circulation, online
Last Updated: Nov. 30, 2009
Copyright © 2009 ScoutNews, LLC. All rights reserved.
Friday, December 25, 2009
Friday, December 18, 2009
Multiple sclerosis 'blood blockage theory' tested
By Michelle Roberts
Health reporter, BBC News
US scientists are testing a radical new theory that multiple sclerosis (MS) is caused by blockages in the veins that drain the brain.
The University of Buffalo team were intrigued by the work of Italian researcher Dr Paolo Zamboni who claims 90% of MS is caused by narrowed veins.
He says the restricted drainage, visible on scans, injures the brain leading to MS.
He has already widened the blockages in a handful of patients.
The US team want to replicate his earlier work before treating patients.
Experts welcomed the research saying it was important to confirm the basic science before evaluating any therapy.
MS is a long-term inflammatory condition of the central nervous system which affects the transfer of messages from the nervous system to the rest of the body.
The Buffalo team, led by Dr Robert Zivadinov, plan to recruit 1,100 patients with MS and 600 other volunteers as controls who are either healthy or have neurological diseases other than MS.
Using Doppler ultrasound, they will scan the patients to see if they can find any blockages within the veins of the neck and brain.
If they can prove Dr Zamboni's theory of "chronic cerebrospinal venous insufficiency", they say it will change our understanding of MS.
Health reporter, BBC News
US scientists are testing a radical new theory that multiple sclerosis (MS) is caused by blockages in the veins that drain the brain.
The University of Buffalo team were intrigued by the work of Italian researcher Dr Paolo Zamboni who claims 90% of MS is caused by narrowed veins.
He says the restricted drainage, visible on scans, injures the brain leading to MS.
He has already widened the blockages in a handful of patients.
The US team want to replicate his earlier work before treating patients.
Experts welcomed the research saying it was important to confirm the basic science before evaluating any therapy.
MS is a long-term inflammatory condition of the central nervous system which affects the transfer of messages from the nervous system to the rest of the body.
The Buffalo team, led by Dr Robert Zivadinov, plan to recruit 1,100 patients with MS and 600 other volunteers as controls who are either healthy or have neurological diseases other than MS.
Using Doppler ultrasound, they will scan the patients to see if they can find any blockages within the veins of the neck and brain.
If they can prove Dr Zamboni's theory of "chronic cerebrospinal venous insufficiency", they say it will change our understanding of MS.
Rewriting science
Margaret Paroski, who is chief medical officer at Kaleida Health, where the Buffalo researchers are based, said the work could overturn prevailing wisdom that the damage in MS is predominantly the result of abnormal immune responses.
"When I was in medical school, we thought peptic ulcer disease was due to stress. We now know that 80% of cases are due to a bacterial infection.
"Dr Zivadinov's work may lead to a whole different way of thinking about MS."
Dr Zamboni, of the University of Ferrara, believes the blockages are the cause rather than the consequence of MS and that they allow iron from the blood to leak into the brain tissue, where it causes damage.
He has performed procedures similar to angioplasty to unblock the veins and get the blood flowing normally again.
He claims this "liberation procedure" can alleviate many of the symptoms of MS and is due to publish his findings in the Journal of Vascular Surgery.
In an interview with CTV News in Canada he said: "I found the evidence of narrowing - narrowing of the veins just in MS patients.
"I'm fully convinced that this is very, very important for people."
Early days
Kevin Lipp, an MS patient from the US, has been symptom-free since being treated by Dr Zamboni.
He said: "It's only been 10 months. If nothing happens in the next two to three years, we'll know it's working."
The BBC has heard anecdotally of other surgeons in Europe testing out the same treatment.
The MS Society said more research was needed to see if this was an avenue that should be explored further.
"This is not something patients can expect as a treatment now. This is experimental work and is being tested. We need to know more about its safety and effectiveness."
Helen Yates, of the MS Resource Centre, said: "There is no doubt that this area warrants a great deal more study.
"This could represent a completely novel approach to MS research which, if proven to be relevant, could be a "sea change" in the understanding of the mechanisms involved in the condition."
Friday, December 11, 2009
Cigarettes May Contain Bacteria
Study Shows Cigarettes May Be Contaminated With Hundreds of Types of Bacteria
By Kelli Miller Stacy
WebMD Health NewsReviewed by Elizabeth Klodas, MD, FACC
Nov. 24, 2009 -- Cigarettes are massive germ factories that may expose users and passersby to a swarm of disease-causing bacteria, a study shows.
It's well known that cigarette smoke harbors hundreds of toxic chemicals that are bad for your health. But a University of Maryland environmental health researcher says that's not the only danger. DNA examination of four cigarette brands shows, for the first time, that cigarettes are "widely contaminated" with hundreds of different types of bacteria. In fact, there appears to be as many bacteria in cigarettes as there are chemicals.
"The commercially available cigarettes that we tested were chock full of bacteria, as we had hypothesized, but we didn't think we'd find so many that are infectious in humans," says researcher Amy R. Sapkota, an assistant professor in the University of Maryland's School of Public Health.
Sapkota and microbial ecologists at the Ecole Centrale de Lyon in France examined the bacteria content in four major cigarette brands: Camel, Kool Filter Kings, Lucky Strike Original Red, and Marlboro Red and found similar types of bacteria in each one.
Previous research has watched for bacterial growth in lab dishes containing small tobacco samples, but this study is the first to scrutinize a cigarette's bacterial genetic makeup.
The testing revealed that cigarettes contain a wide variety of bacteria that are linked to lung, blood, and food-borne-related infections. Among those present were:
Acinetobacter -- associated with certain blood and lung infections
Bacillus -- some types are associated with anthrax and food poisoning
Burkholderia -- some strains can cause respiratory infections
Clostridium -- linked to food poisoning-related illnesses and lung infections
Klebsiella -- associated with many kinds of lung, blood, and other infections
Pseudomonas aeruginosa -- a specific type of bacteria that is responsible for 10% of hospital-acquired infections
"If these organisms can survive the smoking process -- and we believe they can -- then they could possibly go on to contribute to both infectious and chronic illnesses in both smokers and individuals who are exposed to environmental tobacco smoke," Sapkota says.
Although the public health implications of these findings are unclear at present, scientists plan to continue their research to determine if the bacteria can be implicated in tobacco-related diseases. A big question is whether or not cigarette-borne bacteria can survive the burning process and enter the lungs of smokers and grow. Some evidence suggests that some bacteria can spread this way. The bacteria may also be present on, or in, the filter.
The study findings appear online ahead of print in the journal Environmental Health Perspectives.
By Kelli Miller Stacy
WebMD Health NewsReviewed by Elizabeth Klodas, MD, FACC
Nov. 24, 2009 -- Cigarettes are massive germ factories that may expose users and passersby to a swarm of disease-causing bacteria, a study shows.
It's well known that cigarette smoke harbors hundreds of toxic chemicals that are bad for your health. But a University of Maryland environmental health researcher says that's not the only danger. DNA examination of four cigarette brands shows, for the first time, that cigarettes are "widely contaminated" with hundreds of different types of bacteria. In fact, there appears to be as many bacteria in cigarettes as there are chemicals.
"The commercially available cigarettes that we tested were chock full of bacteria, as we had hypothesized, but we didn't think we'd find so many that are infectious in humans," says researcher Amy R. Sapkota, an assistant professor in the University of Maryland's School of Public Health.
Sapkota and microbial ecologists at the Ecole Centrale de Lyon in France examined the bacteria content in four major cigarette brands: Camel, Kool Filter Kings, Lucky Strike Original Red, and Marlboro Red and found similar types of bacteria in each one.
Previous research has watched for bacterial growth in lab dishes containing small tobacco samples, but this study is the first to scrutinize a cigarette's bacterial genetic makeup.
The testing revealed that cigarettes contain a wide variety of bacteria that are linked to lung, blood, and food-borne-related infections. Among those present were:
Acinetobacter -- associated with certain blood and lung infections
Bacillus -- some types are associated with anthrax and food poisoning
Burkholderia -- some strains can cause respiratory infections
Clostridium -- linked to food poisoning-related illnesses and lung infections
Klebsiella -- associated with many kinds of lung, blood, and other infections
Pseudomonas aeruginosa -- a specific type of bacteria that is responsible for 10% of hospital-acquired infections
"If these organisms can survive the smoking process -- and we believe they can -- then they could possibly go on to contribute to both infectious and chronic illnesses in both smokers and individuals who are exposed to environmental tobacco smoke," Sapkota says.
Although the public health implications of these findings are unclear at present, scientists plan to continue their research to determine if the bacteria can be implicated in tobacco-related diseases. A big question is whether or not cigarette-borne bacteria can survive the burning process and enter the lungs of smokers and grow. Some evidence suggests that some bacteria can spread this way. The bacteria may also be present on, or in, the filter.
The study findings appear online ahead of print in the journal Environmental Health Perspectives.
Friday, December 4, 2009
Hygiene obsession may impair skin's ability to stay healthy.
From the UK's Telegraph:
Children should be allowed to play in the dirt because being too clean can impair the skin’s ability to heal itself, new research suggests.
By Murray Wardrop
Published: 8:00AM GMT 23 Nov 2009
Scientists have discovered that bacteria on the surface of the skin play an important role in combating inflammation when we get hurt.
The bugs dampen down overactive immune responses, which can lead to rashes or cause cuts and bruises to become swollen and painful.
The findings support previous research which suggests that exposure to germs during early childhood can prime the immune system to prevent allergies.
The so-called “hygiene hypothesis” has previously been used to explain why increasing numbers of children suffer allergies such as eczema and hay fever in more developed countries.
Parenting groups yesterday welcomed the findings as “a vindication of common sense” and urged parents to allow their children greater freedom to play outdoors.
Experts at the University of California at San Diego made the discovery by studying mice and human cells cultured in their laboratory.
The team, led by dermatologist Professor Richard Gallo, found that common bacteria called staphylococci, can reduce inflammation after injury, when they are present on the skin's surface.
Prof Gallo said: “These germs are actually good for us.”
He said that his team identified for the first time ever a previously unknown mechanism by which a product of staphylococci prevents inflammation.
The effect occurs because of a molecule called staphylococcal lipoteichoic acid that acts on keratinocytes, the primary cell type found in the epidermis – or outer skin layer.
Prof Gallo, whose findings are published in Nature Medicine, added: "The exciting implication of the work is that it provides a molecular basis to understand the hygiene hypothesis and has uncovered elements of the wound repair response that were previously unknown.
"This may help us devise new therapeutic approaches for inflammatory skin diseases."
Parents Outloud, the pressure group, said the research provides scientific support for its campaign to prevent children being mollycoddled by health and safety regulations.
Its spokeswoman, Margaret Morrissey, said: “Parents have become so paranoid about their children playing outside and getting dirty that today’s youngsters are not enjoying a proper childhood.
“You cannot blame parents for this because they are constantly bombarded with advertising telling them they have to buy antibacterial products to keep their children clean and healthy.
“However, hopefully research like this will help parents realise that it’s natural and healthy for children to get outdoors and get mucky and that it doesn’t do their health any harm.”
Sue Palmer, children’s campaigner and author of the book Toxic Childhood, added: “Clearly parents need to make sure their children are hygienic, but wrapping them up in cotton wool and not allowing them exposure to germs is just as damaging.”
Up to four in 10 people in Britain suffer from allergies, research by the charity Allergy UK has found.
The number of children with food allergies has tripled in the past decade, with millions being diagnosed with severe immune system disorders, some of them potentially life-threatening.
Children should be allowed to play in the dirt because being too clean can impair the skin’s ability to heal itself, new research suggests.
By Murray Wardrop
Published: 8:00AM GMT 23 Nov 2009
Scientists have discovered that bacteria on the surface of the skin play an important role in combating inflammation when we get hurt.
The bugs dampen down overactive immune responses, which can lead to rashes or cause cuts and bruises to become swollen and painful.
The findings support previous research which suggests that exposure to germs during early childhood can prime the immune system to prevent allergies.
The so-called “hygiene hypothesis” has previously been used to explain why increasing numbers of children suffer allergies such as eczema and hay fever in more developed countries.
Parenting groups yesterday welcomed the findings as “a vindication of common sense” and urged parents to allow their children greater freedom to play outdoors.
Experts at the University of California at San Diego made the discovery by studying mice and human cells cultured in their laboratory.
The team, led by dermatologist Professor Richard Gallo, found that common bacteria called staphylococci, can reduce inflammation after injury, when they are present on the skin's surface.
Prof Gallo said: “These germs are actually good for us.”
He said that his team identified for the first time ever a previously unknown mechanism by which a product of staphylococci prevents inflammation.
The effect occurs because of a molecule called staphylococcal lipoteichoic acid that acts on keratinocytes, the primary cell type found in the epidermis – or outer skin layer.
Prof Gallo, whose findings are published in Nature Medicine, added: "The exciting implication of the work is that it provides a molecular basis to understand the hygiene hypothesis and has uncovered elements of the wound repair response that were previously unknown.
"This may help us devise new therapeutic approaches for inflammatory skin diseases."
Parents Outloud, the pressure group, said the research provides scientific support for its campaign to prevent children being mollycoddled by health and safety regulations.
Its spokeswoman, Margaret Morrissey, said: “Parents have become so paranoid about their children playing outside and getting dirty that today’s youngsters are not enjoying a proper childhood.
“You cannot blame parents for this because they are constantly bombarded with advertising telling them they have to buy antibacterial products to keep their children clean and healthy.
“However, hopefully research like this will help parents realise that it’s natural and healthy for children to get outdoors and get mucky and that it doesn’t do their health any harm.”
Sue Palmer, children’s campaigner and author of the book Toxic Childhood, added: “Clearly parents need to make sure their children are hygienic, but wrapping them up in cotton wool and not allowing them exposure to germs is just as damaging.”
Up to four in 10 people in Britain suffer from allergies, research by the charity Allergy UK has found.
The number of children with food allergies has tripled in the past decade, with millions being diagnosed with severe immune system disorders, some of them potentially life-threatening.
Friday, November 27, 2009
Advanced Cell Technology seeks to test embryonic stem cells to treat blindness.
From the Los Angeles Times:
November 19, 2009 10:00 am
November 19, 2009 10:00 am
Stem cells could be used to remedy
formerly incurable eye defects which
cause blindness.
Patients with a rare eye disease could be the first to be treated with human embryonic stem cells.
Advanced Cell Technology Inc., a Santa Monica-based biotech company with labs in Massachusetts, announced today that it has asked the U.S. Food and Drug Administration for approval to test retinal cells grown from stem cells in 12 people with Stargardt’s macular dystrophy.
The disease is a childhood version of macular degeneration and affects about one in 10,000 kids. Patients typically begin to lose their central vision between the ages of 6 and 20. As SMD progresses, things may look blurry and distorted, and patients may have trouble adjusting to low light. About half of victims are legally blind by age 50. There is no cure.
Most cases occur when children inherent a faulty version of the ABCA4 gene or the CNGB3 gene from both parents. As a result, the photoreceptor cells in the retina don’t get enough fuel, and they atrophy.
ACT hopes to reverse this by supplying patients with new retinal pigment epithelium cells derived from human embryonic stem cells. The RPE cells have been shown to improve vision in animals, with one study restoring eye function in sick rats and mice to “near-normal” levels. Another study boosted rats’ vision to 70% that of healthy animals. No adverse side effects were found in any of the company’s pre-clinical studies, Dr. Robert Lanza, ACT’s chief scientific officer, said in an interview.
ACT proposes a Phase I/II trial designed to assess the safety and tolerability of its RPE cells. The company and its collaborators would like to recruit a dozen patients with advanced SMD at three sites: the Casey Eye Institute in Portland, Ore.; the University of Massachusetts Memorial Medical Center in Worcester; and the UMDNJ – New Jersey Medical School in Newark.
Amid much fanfare, Geron Corp. received FDA approval in January to use specialized nerve cells made out of human embryonic stem cells to treat a handful of patients paralyzed by spinal cord injuries. Those plans are on hold while the company conducts pre-clinical studies to address some safety concerns about its cells, known as GRNOPC1. Last month, Geron said it expected to initiate its clinical trial in the third quarter of 2010.
Since their creation in 1998, human embryonic stem cells have been a highly controversial area of medical research. The cells are derived from days-old human embryos, which gives them the ability to grow into any type of cell in the body. Some scientists – like those at ACT and Geron – envision using them to grow replacement tissues to treat sick patients. But many people are troubled by the fact that the stem cells are typically made by dismantling and destroying human embryos.
ACT has tried to sidestep the ethical debate by using a different method to create its stem cell lines. Instead of using an entire embryo, the company figured out a way to remove only a single blastomere cell from a three-day-old embryo and turn it into a cell line. Such single-cell biopsies are routinely performed in fertility clinics to screen embryos for devastating genetic diseases, and the procedure leaves the embryo intact. The RPE cells that would be used in the clinical trial were grown from one of the company’s single-blastomere cell lines, Lanza said.
The company is also making and testing RPE cells derived from induced pluripotent stem cells. So-called iPS cells behave like embryonic stem cells but are made by reprogramming mature cells taken from children or adults, not from embryos. However, the reprogramming process currently involves viruses and genetic manipulation techniques that make the cells unsuitable for human therapies.
Lanza said ACT decided to target Stargardt’s macular dystrophy first because it has been designated an “orphan disease” and could benefit from a faster regulatory review. The FDA has 30 days to respond to the company’s filing, made Wednesday, and the clinical trial could begin early next year.
If all goes well, the company plans to seek permission to use its RPE cells to treat age-related macular degeneration, Lanza said. That disorder is much more common, and it destroys the central vision of an estimated 1.75 million Americans.
-- Karen Kaplan
Photo: Scientists from Advanced Cell Technology remove a single cell from a days-old embryo, which was used to create a line of human embryonic stem cells. Stem cells made this way were grown into eye cells that the company hopes will treat patients with Stargardt's macular dystrophy. Credit: Associated Press photo/Advanced Cell Technology
Advanced Cell Technology Inc., a Santa Monica-based biotech company with labs in Massachusetts, announced today that it has asked the U.S. Food and Drug Administration for approval to test retinal cells grown from stem cells in 12 people with Stargardt’s macular dystrophy.
The disease is a childhood version of macular degeneration and affects about one in 10,000 kids. Patients typically begin to lose their central vision between the ages of 6 and 20. As SMD progresses, things may look blurry and distorted, and patients may have trouble adjusting to low light. About half of victims are legally blind by age 50. There is no cure.
Most cases occur when children inherent a faulty version of the ABCA4 gene or the CNGB3 gene from both parents. As a result, the photoreceptor cells in the retina don’t get enough fuel, and they atrophy.
ACT hopes to reverse this by supplying patients with new retinal pigment epithelium cells derived from human embryonic stem cells. The RPE cells have been shown to improve vision in animals, with one study restoring eye function in sick rats and mice to “near-normal” levels. Another study boosted rats’ vision to 70% that of healthy animals. No adverse side effects were found in any of the company’s pre-clinical studies, Dr. Robert Lanza, ACT’s chief scientific officer, said in an interview.
ACT proposes a Phase I/II trial designed to assess the safety and tolerability of its RPE cells. The company and its collaborators would like to recruit a dozen patients with advanced SMD at three sites: the Casey Eye Institute in Portland, Ore.; the University of Massachusetts Memorial Medical Center in Worcester; and the UMDNJ – New Jersey Medical School in Newark.
Amid much fanfare, Geron Corp. received FDA approval in January to use specialized nerve cells made out of human embryonic stem cells to treat a handful of patients paralyzed by spinal cord injuries. Those plans are on hold while the company conducts pre-clinical studies to address some safety concerns about its cells, known as GRNOPC1. Last month, Geron said it expected to initiate its clinical trial in the third quarter of 2010.
Since their creation in 1998, human embryonic stem cells have been a highly controversial area of medical research. The cells are derived from days-old human embryos, which gives them the ability to grow into any type of cell in the body. Some scientists – like those at ACT and Geron – envision using them to grow replacement tissues to treat sick patients. But many people are troubled by the fact that the stem cells are typically made by dismantling and destroying human embryos.
ACT has tried to sidestep the ethical debate by using a different method to create its stem cell lines. Instead of using an entire embryo, the company figured out a way to remove only a single blastomere cell from a three-day-old embryo and turn it into a cell line. Such single-cell biopsies are routinely performed in fertility clinics to screen embryos for devastating genetic diseases, and the procedure leaves the embryo intact. The RPE cells that would be used in the clinical trial were grown from one of the company’s single-blastomere cell lines, Lanza said.
The company is also making and testing RPE cells derived from induced pluripotent stem cells. So-called iPS cells behave like embryonic stem cells but are made by reprogramming mature cells taken from children or adults, not from embryos. However, the reprogramming process currently involves viruses and genetic manipulation techniques that make the cells unsuitable for human therapies.
Lanza said ACT decided to target Stargardt’s macular dystrophy first because it has been designated an “orphan disease” and could benefit from a faster regulatory review. The FDA has 30 days to respond to the company’s filing, made Wednesday, and the clinical trial could begin early next year.
If all goes well, the company plans to seek permission to use its RPE cells to treat age-related macular degeneration, Lanza said. That disorder is much more common, and it destroys the central vision of an estimated 1.75 million Americans.
-- Karen Kaplan
Photo: Scientists from Advanced Cell Technology remove a single cell from a days-old embryo, which was used to create a line of human embryonic stem cells. Stem cells made this way were grown into eye cells that the company hopes will treat patients with Stargardt's macular dystrophy. Credit: Associated Press photo/Advanced Cell Technology
Tuesday, November 17, 2009
Fructose May Raise Blood Pressure
Drinking more than two sweetened sodas a day boosts risk of hypertension, study finds
FRIDAY, Oct. 30 (HealthDay News) -- Here's a new reason to put down that sugary soft drink: Research suggests that a diet high in fructose, a common sweetener, boosts the risk of high blood pressure.
High-fructose corn syrup is found in many processed foods and beverages. Americans consume 30 percent more fructose now than 20 years ago, and researchers have linked higher fructose consumption to the growing obesity epidemic. But scientists weren't sure if a connection existed between fructose consumption and high blood pressure.
In a new study, Dr. Diana Jalal, of the University of Colorado Denver Health Sciences Center, and colleagues studied 4,528 adults without a history of high blood pressure. They examined their fructose intake and found that those who consumed more than 74 grams of fructose per day -- that's the equivalent of the amount in 2.5 sweetened soft drinks -- boosted their risk of high blood pressure by 28 percent to 87 percent, depending on the level of hypertension.
"These results indicate that high fructose intake in the form of added sugars is significantly and independently associated with higher blood pressure levels in the U.S. adult population with no previous history of hypertension," the study authors wrote, adding that future research is needed to determine if lowering fructose intake will also lower blood pressure.
The study findings were scheduled to be presented at the American Society of Nephrology's annual meeting, held Oct. 27 to Nov. 1 in San Diego.
More information
Learn about high blood pressure from the American Heart Association.
-- Randy Dotinga
SOURCE: American Society of Nephrology, news release, Oct. 29, 2009
Last Updated: Oct. 30, 2009
Copyright © 2009 ScoutNews, LLC. All rights reserved.
Tuesday, November 3, 2009
Significant arterial damage may occur after first cigarette, research suggests.
Smoking's Damage Swift, Irreversible
Just 1 Cigarette Can Stiffen Arteries in Young Smokers, Study Shows
By Bill Hendrick
WebMD Health News
Reviewed by Louise Chang, MD
Oct. 27, 2009 -- Cigarette smoking starts inflicting “very significant” damage on the arteries with the very first puffs taken by otherwise healthy young smokers, new research shows.
The damage worsens as time passes and is impossible to reverse, says researcher Stella Daskalopoulou, MD, of the McGill University Health Centre.
The study found that smoking just one cigarette increases the stiffness of the arteries in 18- to 30-year-old smokers by 25% after a treadmill exercise test. It was presented at the Canadian Cardiovascular Congress 2009 in Edmonton, Alberta.
As arteries stiffen, she says, the heart must work harder, increasing the risk for heart disease or stroke.
“Our results are significant because they suggest that smoking just a few cigarettes a day impacts the health of the arteries,” Daskalopoulou says in a news release. “This was revealed very clearly when these young people were placed under physical stress, such as exercise.”
She tells WebMD that the study compared the arterial stiffness of 10 young smokers, who puffed five to six cigarettes a day, to 10 nonsmokers. The median age of the participants was 21 years. Researchers, who included R.J. Doonan and other medical students under her supervision, measured arterial stiffness at rest and after exercise.
Arterial stiffness in all participants was measured using a method called applanation tonometry.
An initial arterial stiffness measurement was performed at rest for each subject to establish a baseline measure for all the participants. Smokers were instructed not to smoke for 12 hours prior to the test.
After the first meeting, the smokers completed two more tests on different days. For one test, they smoked a single cigarette and then repeated a treadmill exercise test. For the other test, smokers were asked to chew a piece of nicotine gum prior to the exercise test. Daskalopoulou found that after exercise:
• Arterial stiffness levels in nonsmokers dropped by 3.6%.
• Arterial stiffness in smokers increased by 2.2%.
• After one cigarette, it increased by 24.5% in the smokers.
• After nicotine gum, stiffness increased by 12.6% in the smokers.
What the study means, she tells WebMD, is that even light smoking in otherwise healthy people damages the arteries, compromising the ability to cope with physical stress, such as climbing stairs.
“The people tested were young and healthy,” she tells WebMD. “We found there was no significant difference at rest between smokers and nonsmokers, but then we got them to exercise, and the difference was clear.”
Cherry Wongtrakool, a pulmonary specialist at the Emory University School of Medicine in Atlanta, tells WebMD there’s no doubt that even one or two cigarettes impairs blood vessel function.
The question is, “how much of that change is going to be persistent,” which she says isn’t answered by the study.
“We know if you have any smoking in your personal history, that puts you at risk for a number of diseases, even if you are a former smoker,” Wongtrakool says.
Daskaloupoulou is working on another study now examining whether former smokers who recently stopped can recover some lung function, and if so, how long it takes.
“This study is very exciting,” Daskalopoulou tells WebMD. “The earlier you stop, my belief is, the faster some recovery will be, but I don’t believe the [arterial] system ever goes back to normal. If you stop early, the damage will be much smaller, but there will still be damage.”
She also says that young people who believe that a little smoking doesn’t hurt are wrong.
Beth Abramson, MD, spokeswoman for the Heart and Stroke Foundation of Canada and director of the Cardiac Prevention Center at St. Michael’s Hospital in Toronto, tells WebMD the study is stunning in that it shows clearly that “harmful effects of smoking show up immediately. This is more evidence to prove that smoking is horrendous to one’s health.”
Any smoking is bad, she says, because “it does the opposite of what nitroglycerin does, which is helps increase blood flow to the heart.”
She says even people who’ve smoked for decades can benefit from quitting, though “it’s going to take longer to take your risk down.”
Just 1 Cigarette Can Stiffen Arteries in Young Smokers, Study Shows
By Bill Hendrick
WebMD Health News
Reviewed by Louise Chang, MD
Oct. 27, 2009 -- Cigarette smoking starts inflicting “very significant” damage on the arteries with the very first puffs taken by otherwise healthy young smokers, new research shows.
The damage worsens as time passes and is impossible to reverse, says researcher Stella Daskalopoulou, MD, of the McGill University Health Centre.
The study found that smoking just one cigarette increases the stiffness of the arteries in 18- to 30-year-old smokers by 25% after a treadmill exercise test. It was presented at the Canadian Cardiovascular Congress 2009 in Edmonton, Alberta.
As arteries stiffen, she says, the heart must work harder, increasing the risk for heart disease or stroke.
“Our results are significant because they suggest that smoking just a few cigarettes a day impacts the health of the arteries,” Daskalopoulou says in a news release. “This was revealed very clearly when these young people were placed under physical stress, such as exercise.”
She tells WebMD that the study compared the arterial stiffness of 10 young smokers, who puffed five to six cigarettes a day, to 10 nonsmokers. The median age of the participants was 21 years. Researchers, who included R.J. Doonan and other medical students under her supervision, measured arterial stiffness at rest and after exercise.
Arterial stiffness in all participants was measured using a method called applanation tonometry.
An initial arterial stiffness measurement was performed at rest for each subject to establish a baseline measure for all the participants. Smokers were instructed not to smoke for 12 hours prior to the test.
After the first meeting, the smokers completed two more tests on different days. For one test, they smoked a single cigarette and then repeated a treadmill exercise test. For the other test, smokers were asked to chew a piece of nicotine gum prior to the exercise test. Daskalopoulou found that after exercise:
• Arterial stiffness levels in nonsmokers dropped by 3.6%.
• Arterial stiffness in smokers increased by 2.2%.
• After one cigarette, it increased by 24.5% in the smokers.
• After nicotine gum, stiffness increased by 12.6% in the smokers.
What the study means, she tells WebMD, is that even light smoking in otherwise healthy people damages the arteries, compromising the ability to cope with physical stress, such as climbing stairs.
“The people tested were young and healthy,” she tells WebMD. “We found there was no significant difference at rest between smokers and nonsmokers, but then we got them to exercise, and the difference was clear.”
Cherry Wongtrakool, a pulmonary specialist at the Emory University School of Medicine in Atlanta, tells WebMD there’s no doubt that even one or two cigarettes impairs blood vessel function.
The question is, “how much of that change is going to be persistent,” which she says isn’t answered by the study.
“We know if you have any smoking in your personal history, that puts you at risk for a number of diseases, even if you are a former smoker,” Wongtrakool says.
Daskaloupoulou is working on another study now examining whether former smokers who recently stopped can recover some lung function, and if so, how long it takes.
“This study is very exciting,” Daskalopoulou tells WebMD. “The earlier you stop, my belief is, the faster some recovery will be, but I don’t believe the [arterial] system ever goes back to normal. If you stop early, the damage will be much smaller, but there will still be damage.”
She also says that young people who believe that a little smoking doesn’t hurt are wrong.
Beth Abramson, MD, spokeswoman for the Heart and Stroke Foundation of Canada and director of the Cardiac Prevention Center at St. Michael’s Hospital in Toronto, tells WebMD the study is stunning in that it shows clearly that “harmful effects of smoking show up immediately. This is more evidence to prove that smoking is horrendous to one’s health.”
Any smoking is bad, she says, because “it does the opposite of what nitroglycerin does, which is helps increase blood flow to the heart.”
She says even people who’ve smoked for decades can benefit from quitting, though “it’s going to take longer to take your risk down.”
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