- Stem - Cells That Divide: A Second Novel in The University Series (Paperback)
- A Novel Method to Apply Osteogenic Potential of Adipose Derived Stem Cells in Orthopaedic Surgery
- Shop with confidence
- Author information
- Hematopoietic Stem Cell Transplantation
And they argue that scientists can achieve the same results using adult stem cells— immature cells found in bone marrow and other organs in adult human beings, as well as in umbilical cords normally discarded at birth. Advocates counter that adult stem cells, useful as they may be for some diseases, have thus far proved incapable of producing the full range of cell types that embryonic stem cells can. They point out that fertility clinic freezers worldwide are bulging with thousands of unwanted embryos slated for disposal.
Those embryos are each smaller than the period at the end of this sentence. They have no identifying features or hints of a nervous system. If parents agree to donate them, supporters say, it would be unethical not to do so in the quest to cure people of disease. Few question the medical promise of embryonic stem cells. Consider the biggest United States killer of all: heart disease. Embryonic stem cells can be trained to grow into heart muscle cells that, even in a laboratory dish, clump together and pulse in spooky unison.
And when those heart cells have been injected into mice and pigs with heart disease, they've filled in for injured or dead cells and sped recovery.
Similar studies have suggested stem cells' potential for conditions such as diabetes and spinal cord injury. Critics point to worrisome animal research showing that embryonic stem cells sometimes grow into tumors or morph into unwanted kinds of tissues—possibly forming, for example, dangerous bits of bone in those hearts they are supposedly repairing. But supporters respond that such problems are rare and a lot has recently been learned about how to prevent them. The arguments go back and forth, but policymakers and governments aren't waiting for answers.
Some countries, such as Germany, worried about a slippery slope toward unethical human experimentation, have already prohibited some types of stem cell research. Others, like the U. Still others, such as the U. In such varied political climates, scientists around the globe are racing to see which techniques will produce treatments soonest.
Their approaches vary, but on one point, all seem to agree: How humanity handles its control over the mysteries of embryo development will say a lot about who we are and what we're becoming. Now having run out of options, he is about to become a biomedical pioneer—one of about Americans last year to be treated with an umbilical cord blood transplant. Cord blood transplants—considered an adult stem cell therapy because the cells come from infants, not embryos—have been performed since Like bone marrow, which doctors have been transplanting since , cord blood is richly endowed with a kind of stem cell that gives rise to oxygen-carrying red blood cells, disease-fighting white blood cells, and other parts of the blood and immune systems.
Unlike a simple blood transfusion, which provides a batch of cells destined to die in a few months, the stem cells found in bone marrow and cord blood can—if all goes well—burrow into a person's bones, settle there for good, and generate fresh blood and immune cells for a lifetime. Propped on a hospital bed at Duke University Medical Center, Cedric works his thumbs furiously against a pair of joysticks that control a careening vehicle in a Starsky and Hutch video game. Just an hour ago I watched those cells being thawed and spun in a centrifuge—awakening them for the first time since , when they were extracted from the umbilical cord of a newborn and donated by her parents to a cell bank at Duke.
The time has come for those cells to prove their reputed mettle. For days Cedric has endured walloping doses of chemotherapy and radiation in a last-ditch effort to kill every cancer cell in his body. Such powerful therapy has the dangerous side-effect of destroying patients' blood-making stem cells, and so is never applied unless replacement stem cells are available. A search of every bone marrow bank in the country had found no match for Cedric's genetic profile, and it was beginning to look as if he'd run out of time.
Then a computer search turned up the frozen cord blood cells at Duke—not a perfect match, but close enough to justify trying. Mom and dad, who have spent hours in prayer, nod yes, and a line of crimson wends its way down the tube, bringing the first of about million cells into the boy's body. The video game's sound effects seem to fade behind a muffling curtain of suspense.
Although Cedric's balloon-laden room is buoyant with optimism, success is far from certain. His mom's eyes are misty. I ask what she sees when she looks at the cells trickling into her son. It will be a month before tests reveal whether Cedric's new cells have taken root, but in a way he's lucky. All he needs is a new blood supply and immune system, which are relatively easy to re-create. Countless other patients are desperate to regenerate more than that.
Diabetics need new insulin-producing cells. Heart attack victims could benefit from new cardiac cells. Paraplegics might even walk again if the nerves in their spinal cords could regrow. In a brightly lit laboratory halfway across the country from Cedric's hospital room, three teams of scientists at the University of Wisconsin in Madison are learning how to grow the embryonic stem cells that might make such cures possible. Unlike adult stem cells, which appear to have limited repertoires, embryonic stem cells are pluripotent—they can become virtually every kind of human cell.
The cells being nurtured here are direct descendants of the ones James Thomson isolated seven years ago. For years Thomson and his colleagues have been expanding some of those original stem cells into what are called stem cell lines—colonies of millions of pluripotent cells that keep proliferating without differentiating into specific cell types. The scientists have repeatedly moved each cell's offspring to less crowded laboratory dishes, allowing them to divide again and again.
And while they worked, the nation struggled to get a handle on the morality of what they were doing. It took almost two years for President Bill Clinton's administration to devise ethics guidelines and a system for funding the new field.
Stem - Cells That Divide: A Second Novel in The University Series (Paperback)
George W. Bush's ascension prevented that plan from going into effect, and all eyes turned to the conservative Texan to see what he would do. On August 9, , Bush announced that federal funds could be used to study embryonic stem cells. But to prevent taxpayers from becoming complicit in the destruction of human embryos, that money could be used only to study the stem cell lines already in the works as of that date—a number that, for practical reasons, has resulted in about two dozen usable lines.
Those wishing to work with any of the more than a hundred stem cell lines created after that date can do so only with private funding. Every month scientists from around the world arrive in Madison to take a three-day course in how to grow those approved cells. To watch what they must go through to keep the cells happy is to appreciate why many feel hobbled by the Bush doctrine.
A Novel Method to Apply Osteogenic Potential of Adipose Derived Stem Cells in Orthopaedic Surgery
For one thing—and for reasons not fully understood—the surest way to keep these cells alive is to place them on a layer of other cells taken from mouse embryos, a time-consuming requirement. Hunched over lab benches, deftly handling forceps and pipettes with blue latex gloves, each scientist in Madison spends the better half of a day dissecting a pregnant mouse, removing its uterus, and prying loose a string of embryos that look like little red peas in a pod.
They then wash them, mash them, tease apart their cells, and get them growing in lab dishes. The result is a hormone-rich carpet of mouse cells upon which a few human embryonic stem cells are finally placed. There they live like pampered pashas. If their scientist-servants don't feed them fresh liquid nutrients at least once a day, the cells die of starvation.
- La sentenza (Narrativa) (Italian Edition)!
- Mateo, Marcos y Lucas (Volumen 1) (Light To My Path Devotional Commentary Series) (Spanish Edition)?
- You are here.
- Search form.
If each colony is not split in half each week, it dies from overcrowding. And if a new layer of mouse cells is not prepared and provided every two weeks, the stem cells grow into weird and useless masses that finally die. By contrast, scientists working with private money have been developing embryonic stem cell lines that are hardier, less demanding, and not dependent on mouse cells.
Bypassing the use of mouse cells is not only easier, but it also eliminates the risk that therapeutic stem cells might carry rodent viruses, thereby potentially speeding their approval for testing in humans. Here in the Madison lab, scientists grumble about how fragile the precious colonies are. You can't help it. They're so great. I see so many good things coming from them. A few American scientists are finding it is easier to indulge their enthusiasm for stem cells overseas. Scores of new embryonic stem cell lines have now been created outside the U. Minger could be right. He is one of at least two high-profile stem cell scientists to move from the U.
The research climate is good here, says Minger. In his team became the first in the U.
- Sicheres Auftreten bei völliger Ahnungslosigkeit (German Edition)!
- Sauvez votre retraite ! (French Edition)!
- World of Warcraft : Le déferlement (Gamers) (French Edition).
- 1. Introduction.
- The Beginners Guide to Dutch Oven Cooking.
- In 7 Tagen fit fürs Assessment Center (German Edition)?
He's developing new growth culture systems that won't rely on potentially infectious mouse cells. He's also figuring out how to make stem cells morph into cardiac, neural, pancreatic, and retinal cells and preparing to test those cells in animals. And in stark contrast to how things are done in the U. In closed-door meetings a committee of 18 people appointed by the National Health Service considers all requests to conduct research using embryos.
Shop with confidence
The committee includes scientists, ethicists, lawyers, and clergy, but the majority are lay people representing the public. To an American accustomed to high security and protesters at venues dealing regularly with embryo research, the most striking thing about the HFEA's headquarters in downtown London is its ordinariness. The office, a standard-issue warren of cubicles and metal filing cabinets, is on the second floor of a building that also houses the agency that deals with bankruptcy. I ask Ross Thacker, a research officer at the authority, whether the HFEA is regularly in need of yellow police tape to keep protesters at bay.
Thacker politely refrains from criticizing U. The committee has approved about a dozen requests to create stem cell lines in the past 18 months, increasing the number of projects to Most were relatively routine—until a strong-willed fertility doctor named Alison Murdoch decided to ask for permission to do something nobody had done before: create cloned human embryos as sources of stem cells.
As controversial as embryonic stem cell research can be, cloning embryos to produce those stem cells is even thornier. Much of the world became familiar with cloning in , when scientists announced they'd cloned a sheep named Dolly. The process involves creating an animal not from egg and sperm but by placing the nucleus of a cell inside an egg that's had its nucleus removed.
It's since been used to replicate mice, rabbits, cats, and cattle, among others. As in many other countries and a few U. In the British Parliament made it legal to create cloned human embryos—as opposed to babies—for use in medical research called therapeutic cloning. Still, no one on the HFEA was completely comfortable with the idea.
The fear was that some rogue scientist would take the work a step further, gestate the embryo in a woman's womb, and make the birth announcement that no one wanted to hear. But Murdoch, of the University of Newcastle upon Tyne, made a compelling case.
If replacement tissues grown from stem cells bore the patient's exact genetic fingerprint, they would be less likely to be rejected by a patient's immune system, she told the committee. And what better way to get such a match than to derive the cells from an embryo cloned from the patient's own DNA? Disease research could also benefit, she said. Imagine an embryo—and its stem cells—cloned from a person with Lou Gehrig's disease, a fatal genetic disorder that affects nerves and muscles.
Scientists might learn quite a bit, she argued, by watching how the disease damages nerve and muscle cells grown from those stem cells, and then testing various drugs on them. It's the kind of experiment that could never be done in a person with the disease.
Hematopoietic Stem Cell Transplantation
The HFEA deliberated for five months before giving Murdoch permission to make human embryo clones in her lab at the Centre for Life in Newcastle, a sprawling neon-illuminated complex of buildings that strikes a decidedly modern note in the aging industrial hub. But there was a catch: It takes an egg to make a clone. Could be, or is there a hidden truth? Anti-stem cell demonstrators occupy the Free Forum area across from Mike's office. They plague him, but that, too, is not the whole truth.
Is there a connection between Mike and their leader, and does a connection emerge between Mike and the woman he thinks of as "Eyes? Then again, it is just possible you may catch a glimpse into the future.
Review This Product No reviews yet - be the first to create one! Need help? Partners MySchool Discovery. Subscribe to our newsletter Some error text Name. Email address subscribed successfully. A activation email has been sent to you. Please click the link in that email to activate your subscription. Sitemap Index. General Imprint:.