Around the Nation

Around the Nation

Researchers develop cell for bones

The researchers at Osiris Therapeutics in Baltimore report in the journal Science that they isolated a single cell, called a mesenchymal stem cell, and then grew it into a colony of more than a million cells that could be induced to produce bone, cartilage or fat.

Other experts in the rapidly expanding field of stem cell research applauded the achievement.

''The fact that they can (isolate) a precursor cell like that, and direct it to produce specific cell types, is quite an advance,'' said James Thomson of the University of Wisconsin, a noted pioneer in stem cell research. ''It may be that such cells can eventually be used for therapy and that would be quite exciting.''

Stem cells are the body's building blocks. Some, such as pluripotent stem cells, come only from embryos and their use in research is opposed by many people. Other stem cells, such as the mesenchymal cells used by Osiris, are produced in adults.

But only the pluripotent stem cells from embryos are thought to be capable of growing into any tissue in the body. The mesenchymal stem cells are the parent lines for bone, cartilage, fat, tendon and muscle.

The Osiris work helps move stem cell research from the laboratory toward the clinic, said Dr. David Anderson, a Howard Hughes Medical Institute stem cell researcher at the California Institute of Technology.

''If you want to use stem cells to replace damaged tissue, you have to first know how to differentiate those cells in the lab dish before you put them into a patient,'' he said.

In their work, Osiris researchers led by Dr. Mark Pittenger grew a single mesenchymal stem cell through more than 20 generations to create about a million cells.

The researchers then altered the culture medium and added proteins that caused the specimens to grow into cell families, or lineages, that would produce bone, tendon or fat, Pittenger said. Other work underway may lead to producing muscle cell lines.

''We've arrived at conditions that allow us a very strong degree of control,'' said Pittenger. ''When we direct these cells to the (cartilage) lineage, almost all of the cells grow to that lineage.''

That means it's very likely that researchers will eventually be able to inject specific types of cells into patients, which then would grow into replacement bone, tendon or muscle, he said.

Laboratory research on animals is already underway and human studies may be possible in three years, he said.

If the technique proves successful, researchers predict that precursor cells for bone could be used to replace tissue lost to cancer, osteoporosis, injury or dental disease.

Research in rabbits and dogs already has shown that gaps in leg bone caused by surgery, such as for cancer, can be filled in with tissue grown in the body from stem cells.

Animal studies also are underway to determine if stem cells injected into the heart can replace scar tissue caused by heart attack.

The study using adult stem cells is important also because it avoids the controversy of using stem cells from embryos, Pittenger said.

Congress has banned federal financing of research using human embryos, and some lawmakeppose a National Institutes of Health plan to possibly pay for embryonic stem cell research.

But Thomson, one of the first to isolate stem cells from human embryos, said that although researchers have proven that some types of stem cells can be obtained from adults, there is still a scientific need for embryonic stem cell research.

There are no known adult stem cells for some critical organs, such as kidney, heart and lung, he noted. If replacements are to be grown for these parts, Thomson said, it would require embryonic stem cell research.

Aviator: Destorying tape was big mistake

"I wish I had left it there. The videotape didn't have anything to do with the mishap," Capt. Joseph Schweitzer, who was the jet's navigator, testified at his sentencing hearing.

Schweitzer could receive up to 10 years in prison after pleading guilty to obstruction of justice and conspiracy charges Monday, telling a judge he threw the videotape into a bonfire. A nine-member military jury is hearing testimony before recommending a sentence.

The defense rested its case following Schweitzer's testimony. Court was to resume today with closing arguments.

The Marine EA-6B Prowler was on a low-level training flight near Cavalese, Italy, on Feb. 3, 1998, when it severed the ski gondola cable, sending it hurtling 370 feet to the ground and killing everyone aboard. The jet limped back to the air base at Aviano, Italy.

"What I pleaded to was a big mistake, a big mistake," Schweitzer said. "I will live with it the rest of my life. It doesn't change my core. I'm taking responsibility for that today."

Schweitzer choked up while describing when he learned people in the ski gondola had died.

"It was the worst moment I ever had in my life," he said. "Every thought of happiness and joy seeped out of my body."

A backseat crewman testified earlier yesterday that he advised Schweitzer and the jet's pilot, Capt. Richard Ashby, to destroy the videotape because he felt abandoned by higher-ups and was concerned about the hostility of the Italian news media.

"It surprises me that I made that decision," said Capt. Chandler Seagraves. "It's wrong as a Marine Corps officer. Two fellow Marines were asking my advice as a Marine Corps officer, and I steered them in the wrong direction."

After the accident, the crew was removed from the air base to answer questions by Italian investigators, Seagraves said. When they came outside there was no one to take them back to the base, he said.

"It seemed like nobody actually cared what happened," Seagraves said. "That started scaring all of us."

Seagraves was granted immunity to testify. Charges against him and the other backseat crewman, Capt. William Raney of Englewood, Colo., were dropped last year.

Ashby, 32, of Mission Viejo, Calif., was acquitted last month by a separate jury of manslaughter charges. He still faces trial on obstruction charges.

$180 million pooled for school programs

The departments of Education, Justice and Health and Human Services are pooling money granted by Congress, agency officials announced yesterday. Applications for the Safe Schools/Healthy Students program are due June 1.

''There so many components that go into making schools safe,'' said George Raiss, lobbyist for the 37,000-student Norfolk, Va., school district. ''If the grants enable us to put all of our efforts under one umbrella, then this is something we'd definitely go after.''

The Justice Department's share this year includes $80 million from a program to hire community police officers. But officials stressed that putting more police in schools isn't the plan's focus.

''No one group can do it by themselves,'' Attorney General Janet Reno said. ''Police chiefs and officers tell me ... we've got to do more in terms of prevention. Schools ... can't teach their children unless they feel that children are safe.''

Reno said the medical community must address the mental health issues that bring about some violence.

In Anaheim, Calif., police officers work in the schools to build a rapport with students, so if they get into trouble with the law, they deal with officers they know and trust. But when it is time for counseling, the 30,000-student district has trouble finding affordable mental health services.

''They don't do a lot of volunteer work,'' said Bob Montenegro, safe schools coordinator for the Anaheim Union High School District, which covers Anaheim, Buena Park and other cities. ''That's the area we really need help in.''

The grants come out of last fall's White House conference on school safety where President Clinton called for a stronger federal role in violence prevention.

The administration hopes Congress will approve $120 million more over the next two years.

After highly publicized shootings in the 1997-98 school year in towns such as West Paducah, Ky., Jonesboro, Ark., and Springfield, Ore., schools were forced to examine how to guarantee children's safety and address public thinking that deadly youth violence is on the rise.

''Those tragic incidences ... really focused the nation on school violence,'' Education Secretary Richard Riley said.

The latest figures available, from the 1996-97 school year, show 10 percent of the nation's public schools reported violent crimes. Most incidents were concentrated in larger and urban districts.

Reno said the grants would be available to communities of all sizes: ''This type of tragedy happens everywhere.''

04-02-99