Stem cell breakthrough defuses debate
Wed, 21 Nov 2007 07:19:01 GMTBy MALCOLM RITTER, AP Science Writer
NEW YORK - Scientists have created the equivalent of embryonic stem cells from ordinary skin cells, a breakthrough that could someday produce new treatments for disease without the explosive moral questions of embyro cloning.
Research teams in the United States and Japan showed that a simple lab technique can rival the complex and highly controversial idea of extracting stem cells from cloned embryos.
It was a landmark achievement on all fronts, defusing one of the most divisive debates in modern medicine and religion. It was lauded by scientists, ethicists and religious groups.
"This work represents a tremendous scientific milestone — the biological equivalent of the Wright Brothers' first airplane," said Dr. Robert Lanza, whose company, Advanced Cell Technology, has been trying to extract stem cells from cloned human embryos.
"It redefines the ethical terrain," said Laurie Zoloth, a bioethicist at Northwestern University.
"It's a win-win for everyone involved," said the Rev. Thomas Berg of the Westchester Institute, a Roman Catholic think tank. "We have a way to move forward which ... brings the kind of painful national debate over this controversial research to very much a peaceful and promising resolution."
At the White House, President Bush, who vetoed two bills to allow federal funding for stem-cell research, was described as "very pleased."
"The president believes medical problems can be solved without compromising either the high aims of science or the sanctity of human life," said a statement from his press secretary.
The new technique reprograms cells, giving them the chameleon-like qualities of embryonic stem cells, which can morph into all kinds of tissue, such as heart, nerve and brain. As with embryonic cells, the hope is to speed medical research. For example, one day an ailing patient might benefit from genetically matched healthy tissue that would replace damaged cells.
The research was published online Tuesday by two journals, Cell and Science. The Cell paper is from a team led by Dr. Shinya Yamanaka of Kyoto University; the team published by Science was led by Junying Yu, working in the lab of stem-cell pioneer James Thomson of the University of Wisconsin-Madison.
Both groups reported that the reprogrammed cells behaved like stem cells in a series of lab tests. Their papers ended a scientific race that broke into wide view just this summer, when the achievement was reported in mice.
The scientists themselves were startled by their success.
"I was surprised when we achieved our results with the mouse," Yamanaka said. "But proving what we could do with human cells really bowled me over."
Thomson said he was surprised it didn't take longer to discover how to reprogram ordinary cells. The technique, he said, is so simple that "thousands of labs in the United States can do this, basically tomorrow."
In contrast, the cloning approach is so complex and expensive that many scientists say it couldn't be used routinely to supply stem cells for therapy.
While the discovery seems likely to shift the direction of research, Thomson and others said it's too soon to give up on studying embryonic stem cells.
He said he believes the ethical turmoil surrounding the embryonic cells set the field back four or five years. The new results are "probably the beginning of the end for that controversy," he said.
But he said his team wasn't trying to find a way around the ethical debate by pursuing the new technique. "We just thought this was a more practical approach," he said.
An official of one group fiercely opposed to destroying embryos saw things differently, saying scientists should thank "pro-life voices" for pushing them to find alternatives.
"The results are groundbreaking studies like these," said Carrie Gordon Earll, bioethics analyst for Focus on the Family, a conservative Christian group.
The controversy over embryonic stem cells has been a touchstone of national politics. It inspired impassioned pleas by Nancy Reagan, the actor Michael J. Fox, who suffers from Parkinson's disease, and countless ordinary citizens arguing in favor of the potential medical benefits.
Equally heartfelt were objections that destroying embryos to extract the stem cells meant destroying human life.
No federal money was available for embryonic stem cell research until 2001, when President Bush allowed very limited funding. Some states like California and Connecticut responded to his restrictions by setting up their own programs to pay for it.
The new work shows that like cloning, "direct reprogramming" can also use ordinary body cells to create versatile cells that are genetically matched.
"It's a bit like learning how to turn lead into gold," said Lanza, while cautioning that the work is far from providing medical payoffs.
"It's a huge deal," agreed Rudolf Jaenisch, a prominent stem cell scientist at the Whitehead Institute in Cambridge, Mass. "You have the proof of principle that you can do it."
There is a catch. At this point, the technique disrupts the DNA of the skin cells, and that creates the potential for developing cancer. So it would be unacceptable for transplanting into a patient.
But the DNA disruption is just a byproduct of the technique, and experts said they believe it can be avoided.
For the new work, the two scientific teams chose different cell types from a tissue supplier. Yamanaka reprogrammed skin cells from the face of an unidentified 36-year-old woman, and Thomson's team worked with foreskin cells from a newborn. Thomson's team, which was working its way from embryonic to fetal to adult cells, is still analyzing its results with adult cells.
Both labs did basically the same thing. Each used viruses to ferry four genes into the skin cells. These particular genes were known to turn other genes on and off, but just how they produced cells that mimic embryonic stem cells is a mystery.
Both Thomson, 48, and Yamanaka, 45, had already produced notable achievements. Thomson made headlines in 1998 when he announced that his team had isolated human embryonic stem cells.
And Yamanaka gained scientific notice in 2006 by reporting that direct reprogramming in mice had produced cells resembling embryonic stem cells, although with significant differences. In June, his group and two others announced they'd created mouse cells that were virtually indistinguishable from stem cells.
Zoloth, the ethicist at Northwestern, noted that direct reprogramming avoids not only embryo destruction, but also the need for unfertilized human eggs to create embryos. Eggs are hard to obtain for research, and collecting them subjects women to drug treatment and surgery. Using eggs also raises the ethical question of whether women should be paid for them.
The embryo and egg issues were "show-stopping ethical problems," she said.
Another advantage of direct reprogramming is that it would qualify for federal research funding, unlike projects that seek to extract stem cells from human embryos, noted Doug Melton, co-director of the Harvard Stem Cell Institute.
Still, scientific questions remain about the cells produced by direct reprogramming, called "iPS" cells. One is how the cells compare to embryonic stem cells in their behavior and potential. Eventually, iPS cells might prove better for some scientific uses and cloned stem cells preferable for other uses. For example, scientists want to study the roots of genetic disease and screen potential drug treatments in their laboratories.
Scottish researcher Ian Wilmut, famous for his role in cloning Dolly the sheep a decade ago, has said he is giving up the cloning approach to produce stem cells and plans to pursue direct reprogramming instead.
Other scientists said it's too early for the field to give up studying stem cells from embryos.
Dr. George Daley of the Harvard institute, who said his own lab has also achieved direct reprogramming of human cells, said it's not clear how long it will take to get around the cancer risk problem.
His lab is pursuing both the reprogramming and cloning strategies.
"We'll see, ultimately, which one works and which one is more practical," he said,
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On the Net:
Journal Cell: http://www.cell.com
Journal Science: http://www.sciencemag.org
Heart disease kills more women under 45
Tue, 20 Nov 2007 22:31:49 GMTBy MIKE STOBBE, AP Medical Writer
ATLANTA - For decades, heart disease death rates have been falling. But a new study shows a troubling turn — more women under 45 are dying of heart disease due to clogged arteries, and the death rate for men that age has leveled off.
Heart experts aren't sure what went wrong, but they think increasing rates of obesity and other risk factors are to blame.
The rates will have to be monitored to see if this is the beginning of a real trend. But if the data holds, the new study may be an early glimpse of the impact of escalating obesity and diabetes on U.S. deaths, said Wayne Rosamond, a University of North Carolina epidemiology professor and expert on heart disease statistics.
"This could be a harbinger of things to come," Rosamond said.
To be sure, the overall trend is still positive: From 1980 through 2002, the death rate from blocked heart arteries was cut in half for men and women over 35. Improvements in treatment and preventive measures, including cholesterol-lowering medications, get the credit.
But what's going on with younger adults is startling, said Dr. Anthony DeMaria, editor of the Journal of the American College of Cardiology, which is publishing the study and released it Monday.
"We have a pretty rosy view of how things are going in the war against cardiovascular disease," DeMaria said. "I view this paper as a wake-up call that says there is a very important segment of our population that needs some attention."
Heart disease is the leading cause of death in the United States, killing almost 700,000 Americans each year.
Nearly 500,000 of those deaths are attributed to coronary heart disease, in which fat and plaque clog the arteries feeding blood to the heart, sometimes called hardening of the arteries. Heart attacks are a common result.
It can take many years for arteries to get dangerously blocked. About 93 percent of deaths occur in people 55 and older.
But a combination of factors — including genetics, obesity and high cholesterol — are sometimes fatal for younger adults. In 2002, about 25,000 men and 8,000 women ages 35 to 54 died of coronary heart disease.
The study was done by researchers at the U.S. Centers for Disease Control and Control and Prevention and Britain's University of Liverpool. They looked at U.S. vital statistics for artery-related deaths in adults ages 35 and older for the years 1980 through 2002, the most recent year for which data was available when the analysis was done.
When they compared age groups, they detected the worrisome difference. The study found the death rate for women ages 35 to 44 rose from 1997 to 2002, when the rate was 8.2 per 100,000 women, the highest it's been since 1987.
In actual numbers, the increase amounts to roughly 100 added deaths a year of women in that age group. That's a relatively small impact in the entire U.S. population.
Still, the results are statistically significant and a legitimate cause for concern, said Dr. Wayne Giles, director of the CDC's division of adult and community health.
"That's like an MD-88 crashing every year," he said, referring to a medium-size commuter jet plane.
The rates for men age 35 to 44 were relatively stable in the last few years of the study period. The rate was 26 deaths per 100,000 men in that age group in 2002.
The fact the male rate didn't worsen may indicate doctors are more likely to suspect heart disease in men that age than in women, said the CDC's Dr. Earl Ford, a study co-author.
For all ages, the female death rate fell to 261 from 514 per 100,000; the male rate fell to 430 from 898 per 100,000.
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On the Net:
Journal of the American College of Cardiology: http:// http://www.acc.org/JACC/Ford.pdf
Principal to donate a kidney to student
Tue, 20 Nov 2007 22:32:06 GMTFRANKLIN, N.H. - School principals like to leave a lasting impression on students, and Franklin Middle School's Jim Friel is going the extra mile. Friel is donating a kidney to a 13-year-old eighth-grader.
"I've spent 24 years in education trying to make a difference," said Friel, the father of two adult boys. "This is the best opportunity I've had so far."
When Friel heard that Morgan Corliss needed a kidney and that his blood type was a match, he joined others who went to Boston Children's Hospital to see if his kidney would be a match.
He said he was notified last week by Morgan's mother that he was one of two possible matches and that the family had chosen him.
Friel said he had a heart-to-heart conversation with his wife, Cathy, and their two sons, who, though concerned for his health, support his decision.
"My youngest son is a teacher's aide here at school and he looked at me and said 'You're a good man, Charlie Brown,'" said Friel.
Morgan was diagnosed with FSGS when she was 4 years old. It prevents her kidneys from filtering out impurities.
Morgan's aunt, Christine McAllister, said the teen was relatively healthy until she needed spleen and gall blader surgery last January.
"She's lost about 85 percent of her kidney function in the past year," said McAllister who said the goal is to get Morgan a new kidney before she needs dialysis, which would keep her on a machine for up to 12 hours a day.
"Things for Morgan have been going downhill fast during the past three months," said Friel, who said he is scheduling physicals and doctor appointments in preparation for surgery.
"There is an extensive screening process at any time if any doctor has any doubts about this, he or she could say no," said Friel. "Just because I'm committed it doesn't mean it's a sure thing."
Friel said he is nervous about the surgery, which could come in January.
"But when I talk to Morgan and I see the smile on her face when she sees the possibility of what her life will be like after this, it makes me know I'm doing the right thing," he said.
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Information from: Citizen, http://www.citizen.com
