Mostrar código-fonte de Stem cells em Portugal

CORTNEY'S WISH: After stem-cell surgery, the wait 

===Temperance teen recovers in Portugal===
January 10, 2005 

BY PATRICIA ANSTETT
FREE PRESS MEDICAL WRITER 

LISBON, Portugal -- A tissue sample no bigger than the tip of her baby finger, taken from high inside Cortney Hoffman's nose, holds hope of her recovery from a paralyzing spinal cord injury. The specimen contained more than 2 million adult stem cells, some of the near-magical components of the human body because of their ability to take on tasks of other cells where they are transplanted. 

Place them in the heart and they help perform blood-pumping functions. 

Put them in a damaged spinal cord like doctors did to Cortney on Saturday and they are believed to take on the Herculean job of sending electrical signals to the brain and back to trigger and to move damaged muscles. 

Inserted into the injury site in Cortney's spinal cord by neurosurgeon Dr. Pratas Vital, the cells become the body's molecular jewelry. They even look like small, uncultured pearls, one powerful clump nestled next to each other. 

"They look brand new," said Dr. Carlos Lima, chief of the spinal cord autograft team at Lisbon's Hospital de Egas Moniz. 

Most important, the cells need to act brand new, creating new nerve cells, neural connections and blood vessels so Cortney, 18, of Temperance can regain some of the sensation and movement she lost two years ago in an auto accident. 

Her wish is to walk again. But it will take at least two years of exhaustive rehabilitation to find out just how much recovery she might get from taking a chance on experimental surgery. 

Most medical leaders in the field are taking a wait-and-see approach until more results are published. But that hasn't deterred hundreds of people with spinal cord injuries, now booked for the surgery through the end of May. 

Cortney's five-hour surgery Saturday was the 37th performed by the team. 

On Friday, 20-year-old Amy Foels of Elkader, Iowa, a student at Kirkwood College, Cedar Rapids, became the 36th person in the world to undergo the procedure. 

She, too, was injured in a 2002 auto accident. 

"It was Senior Skip Day and she and the others took off to go drinking and driving," said her longtime boyfriend Brent Duffy, who joined Foels and her parents for the trip. Foels, a passenger, was paralyzed from just above her hips. The other four escaped with no injuries. 

More than half of all spinal cord injuries occur to people ages 16-30. Four of every five occur in men; nearly 40 percent are caused by motor vehicle accidents. Fittingly, perhaps, the Rehabilitation Institute of Michigan in Detroit, the historic home of the automobile, hopes to offer a new legacy to auto accident survivors and others by becoming the first U.S. center to perform autologous spinal cord autograft procedures, as the Lisbon team calls them. 

The institute is working with the Lisbon team to bring the procedure to Detroit by next year, if federal Food and Drug Administration officials allow a clinical study to proceed. First, the Lisbon team and others in Detroit and elsewhere must provide convincing basic science that the operations are safe and effective. The Rehabilitation Institute is evaluating people interested in going to Lisbon, following up on their results and providing the aggressive therapy required to maximize the benefits of the surgery. (For details, see www.centerforscirecovery.org). 

'''The many phases'''
Up to now, little has been known about the Lisbon operation. There are no published studies on humans, only on small animals. Spinal cord patients are hungry for information about the surgery that costs $47,600, often is uncovered by insurance and requires a difficult overseas flight for someone who uses a wheelchair. They wonder if they should wait for something better or if adult stem cells are their best hope for recovery. 

Hospital administrators allowed a Free Press reporter and photographer unprecedented access to the team and the surgery, from beginning to end. 

The operation has five distinct phases. Seven senior physicians with experience in back and ear, nose and throat procedures, brain and spinal cord pathology and anesthesiology do the surgery. 

Phase one: Vital and Dr. Armando Hasse Ferreira, slowly make a 6-inch incision in Cortney's back to peel or sear away the skin, then layer after layer of paper-thin tissue. Vital calls this the orthopedic phase because it relies on bony landmarks and uses plier-like equipment used to replace hips and knees. 

They stop first at a bony protrusion on the vertebrae, 33 structures that ring the back like a chain, separated by spongy discs, the shock absorbers of the back. Then, they count from the highest bone in the neck to the injury site identified in Cortney's X-rays and magnetic resonance imaging tests (MRI). 

But the two experienced neurosurgeons don't find the hallmark sign of many spinal cord injuries: a fluid-filled cyst, or cavity, where the images suggest it would be. This forces them to remove more tissue and bony protrusions that stick out like wings from the vertebrae, a half-inch higher up. It increases the risk of the surgery because it involves vital areas that control breathing. The surgeons use a high-powered microscope in the operating room to find a two-inch cyst. They clear away scar tissue, particularly at each end of the cavity to help any regenerated nerve signals fire more rapidly through the cord. Then they carefully open a hard layer called the dura mater over the spinal cord. 

The cord is surprisingly soft and jelly-like, one of the body's softer, more vulnerable tissues, not the tough column many people might envision. 

Phase Two: Two hours after the start of the surgery, ear, nose and throat specialists Dr. Pedro Escada and Dr. Clara Capucho, enter the OR to perform their vital part of the operation while the two neurosurgeons escape to the staff lounge below for an hour of sleep on a few short sofas. 

Escada and Capucho's job is to extract a tissue sample from the upper reaches of Cortney's nose. There, olfactory mucosal cells that provide the sense of smell and breathing contain neural stem cells capable of regrowing elsewhere. Escada inserts a thin tube a foot long with a lighted tip to guide him while inserting another instrument up the nostril to get the cells. 

The instrument lights up Courtney's nose like a little night-light, casting a red glow, and projects an image onto a TV screen in front of the surgical team. They squirt drugs into her nose to reduce bleeding, before slowing moving in a tool to carefully remove tissue. The region is just a few inches from the brain, so Escada proceeds slowly before he takes the tissue sample and places it in a small metal bowl that contains cerebrospinal fluid extracted from the space around Cortney's spinal cord. 

The team doesn't try to separate the stem cells, Lima says, because the tissue contains other types of cells the spinal cord needs. "One type of cell can't do the whole job," he said of stem cells. "It's like all the people you need to build a house." 

The olfactory mucosal tissue is one of the first structures in embryonic development to appear, even before the spinal cord, Lima said. "It shows it's capable of differentiating" or becoming another type of cell, he said. 

Escada and Capucho pack the nose with biodegradable materials to stop any bleeding then exit the room. 

Phase Three: Now it's Lima's turn. Though he's the team's chief, he has been largely standing on the sidelines up to now, watching the troops and making himself available for consultation about the site of the spinal cord injury. He's now gowned and gloved, sitting at a table with a small block, like a jeweler examining a gem with a magnifying eyepiece, only this time, it's a high-power microscope. He examines the tissue, sends off two small samples for analysis and research, and prepares it for the neurosurgeons. 

Phase Four and Five: Refreshed, Vital and Ferreira reenter the room for the fourth transplant phase. They take the clumps of tissue Lima prepared and place them a few pieces at a time over the spinal cord cavity. It's covered with a glue-like substance before the pocket is closed. 

The final phase uses standard surgical finishing techniques to close the incision. Vital and Ferreira use multiple stitches and knots to sew each layer back into place, like tailors finishing a fine garment. 

A team of veteran nurses and anesthesiologist Dr. Cristina Ferreira remove breathing and other tubes and help Cortney awake from her deep slumber. They pat her face, arms and legs and tell her she's waking up. When someone utters her name, Cortney's eyes bounce wide open for the first time. She tries to talk but can't for a few minutes until her mother and father greet her in the intensive care unit. 

"My head's kinda pounding," she tells her mother Tammi Roe. 

"You didn't think it was going to be a breeze, did you?" her mother replies. 

Cortney goes back to sleep, sleeping through the night, hoping to experience the new sensations and tingling feelings in the next few days which would signal the start of her wish to recover. 

==Autor==
PATRICIA ANSTETT at anstett@freepress.com.
 

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