|
SCIENCE IN THE NEWS - A Replacement Bladder, Grown in the Lab From Patients' Own CellsBy Caty Weaver and Jill Moss
Broadcast: Tuesday, May 09, 2006
(MUSIC)
VOICE ONE:
This is SCIENCE IN THE NEWS in VOA Special English. I'm Bob Doughty.
VOICE TWO:
And I'm Steve Ember. This week: Human organs grown in a laboratory ...
VOICE ONE:
Health and the power of prayer ...
VOICE TWO:
Tiktaalik: scientists think it was among the first sea creatures to walk on land
And scientists fill a missing link in the fossil record between fish and land animals.
(MUSIC)
VOICE ONE:
Seven young people with diseased bladders have received new organs grown from their own cells. Doctors in the United States have described the experimental treatment in a report published in the Lancet.
The seven children and teenagers were born with incomplete closure of the backbone. This disorder affected their bladder, the small organ that stores the body's liquid wastes. High pressure from bladder disease can damage the kidneys. Also, their bladders leaked urine, as often as every thirty minutes.
VOICE TWO:
Doctor Anthony Atala began work on engineering bladders in nineteen ninety. Nine years later, he operated on the first patient. The seven patients were ages four to nineteen. At the time, he directed a tissue engineering program at Harvard Medical School in Massachusetts.
Dr. Anthony Atala
In two thousand four Doctor Atala moved to the Wake Forest University School of Medicine in North Carolina. He directs the Wake Forest Institute for Regenerative Medicine.
VOICE ONE:
The organs are grown from bladder cells and muscle cells taken from the patient. Through the process of culturing, the cells divide and grow in the laboratory.
Lab Grown Bladders
The cells are placed on a structural form shaped like a bladder. Cells are placed on top of cells on top of other cells. Doctor Atala compares the process to making a layer cake.
The bladder is then warmed. The cells continue to grow until the new organ is ready.
Doctors then remove part of the diseased bladder and attach the new one, still connected to the structure. The form is made of material that breaks down in the body.
The body can reject tissue that comes from another person. In this case, since it grew from the patients' own cells, there was no risk of rejection.
VOICE TWO:
The complete process takes about two months. The doctors report that so far, the engineered bladders have worked well. The seven patients must empty them through a tube. But the leakage problem improved and, most importantly, the dangerous pressure eased.
Doctors for a century have used tissue from the intestines to repair bladders. But problems are common with this method.
Testing of the new bladders will continue. Doctor Atala is now working to produce twenty different tissues and organs, including hearts. He says regenerative medicine could someday be an answer to the shortage of replacement organs around the world.
VOICE ONE:
Sixteen-year-old Kaitlyne McNamara, one of Doctor Atala's patients, has had her new bladder for five years. Before that, her kidneys were close to failure. Now they are working well. And she says her quality of life has improved now that accidental leaks have stopped. She says she no longer has to worry about people making fun of her.
(MUSIC)
You are listening to SCIENCE IN THE NEWS in VOA Special English from Washington.
VOICE TWO:
A study that was supposed to end debate about the power of prayer has instead added to it.
The Study of Therapeutic Effects of Intercessory Prayer, or STEP, is the largest prayer research project ever completed. Intercessory prayer is when a person prays for another person.
STEP began in ninety ninety-nine and involved researchers from six medical centers in the United States. The study cost more than two million dollars. Most of it came from the John Templeton Foundation in Pennsylvania. That private group works on issues of religion and science.
The researchers studied just over one thousand eight hundred hospital patients with heart disease. Each person had a coronary artery bypass graft. Doctors perform this operation when blood flow to the heart muscle is restricted.
VOICE ONE:
One of the study leaders was Jeffrey Dusek of Harvard Medical School. He says the main goal was to learn if intercessory prayer, or the knowledge of receiving it, would influence the patients and their recovery.
The researchers asked members of three Christian groups to say the same prayers for about two-thirds of the patients. No one was asked to pray for the others.
Two of the religious groups were Catholic and the other Protestant. Each member received the name of one patient.
Half of those named in the prayers were told that someone was praying for them. Those in the other half were told that someone might pray for them.
The praying started the day before the operation and continued for fourteen days.
VOICE TWO:
The study noted any medical complications for thirty days after the operations. The researchers say there were problems in fifty-nine percent of the patients who knew they were being prayed for.
That compared to fifty-two percent of the patients who were named in prayers but were not sure if someone was praying for them. And it compared to fifty-one percent of the patients who were not named in prayers.
The scientists say all three groups had similar rates of major complications and death within the thirty days.
They say the findings show that intercessory prayer itself had no effect on a complication-free recovery. But they say people who knew they were receiving it were more likely to have problems.
Some researchers involved with the study say telling patients that someone is praying for them might increase their worries about their condition.
VOICE ONE:
The American Heart Journal published the findings. The researchers say all the patients had similar religious beliefs and most believed in spiritual healing power.
Many of the patients said family and friends would be praying for them. And researchers expected that some patients would pray for themselves.
Researcher Herbert Benson from Harvard Medical School says the study does not mean people should stop praying for others. Doctor Benson says the study raises more questions than answers.
It has also raised criticisms. These include the argument that studies of religious or spiritual effects on health are a waste of time and money. Some say people believe in prayer because it has worked for them or someone they know. Others say research money would be better spent on treatments based on medical science.
(MUSIC)
VOICE TWO:
Scientists have evidence of a fish that lived three hundred seventy-five million years ago. They suspect it was among the first sea creatures to walk on land.
Neil Shubin of the University of Chicago and Edward Daeschler with the Academy of Natural Sciences in Philadelphia reported the discovery. Their team found several fossil remains of the fish on Ellesmere Island in northern Canada.
The fish measured between one and three meters long. The scientists say it had extended fins to help with balance and swimming. But they also note qualities that suggest the beginnings of a land creature.
The fossils have simple, hand-like structures that show the beginnings of fingers. There is also evidence of wrists, elbows and shoulders.
The fish had a flat head, a neck and other similarities to four-legged land animals known as tetrapods. The first tetrapods lived about three hundred sixty-five million years ago.
VOICE ONE:
The scientists call the ancient fish Tiktaalik [tic-TAH-lick] roseae. Tiktaalik is a word known to people native to Canada's Nunavut Territory, where the fossils were discovered. It means a large fish that swims in low water.
The scientists say Tiktaalik was a freshwater fish. At that time, weather on Ellesmere Island was much warmer. The area was then part of a continent near the equator.
The magazine Nature published the discovery. It also published comments by two independent scientists. Both describe Tiktaalik as a clear link between fishes and the first animals to live on land.
(MUSIC)
VOICE TWO:
SCIENCE IN THE NEWS was written by Caty Weaver and Jill Moss. Cynthia Kirk was our producer. I'm Steve Ember.
VOICE ONE:
And I'm Bob Doughty. Read and listen to our shows at www.unsv.com. Join us next week for more news about science, in Special English, on the Voice of America.
|