TUESDAY, July 22 (HealthDay News) -- Adult stem cells that may prove valuable in efforts to develop nonsurgical treatments for spinal cord injuries have been identified by researchers in the United States and Sweden.

They say it may be possible to develop drugs that boost the ability of these stem cells to repair damaged nerve cells.

An adult's spinal cord contains only a small number of stem cells, which proliferate slowly or rarely and don't promote regeneration on their own. But some research has shown that spinal cord stem cells grown in the lab and returned to the injury site can restore some physical function in paralyzed rodents and primates.

In this new study, scientists at MIT's Picower Institute for Learning and Memory in Cambridge, Mass., and at the Karolinska Institute in Stockholm found that neural stem cells in the adult spinal cord are limited to a layer of cells called ependymal cells, which make up the thin membrane lining the inner-brain ventricles and the connecting central column of the spinal cord.

"We have been able to genetically mark this neural stem cell population and then follow their behavior. We find that these cells proliferate upon spinal cord injury, migrate toward the injury site and differentiate over several months," study author Konstantinos Meletis said in an MIT news release.

"The ependymal cells' ability to turn into several different cell types upon injury makes them very interesting from an intervention aspect. Imagine if we could regulate the behavior of this stem cell population to repair damaged nerve cells," Meletis said.

The research was published in the July issue of PLoS Medicine.

More information

The U.S. National Institute of Neurological Disorders and Stroke has more about spinal cord injury.

TUESDAY, July 15 (HealthDay News) -- Children suffering from juvenile arthritis who haven't had luck with other treatments may benefit from a drug called Orencia (abatacept).

The conclusions follow from a randomized trial of 122 patients aged 6 to 17 from 45 centers in Europe and in the United States. All participants had a history of juvenile idiopathic arthritis and had at least five joints with active disease. All had tried and failed at least one previous drug.

Participants were randomly assigned to receive 10 milligrams per kilogram of Orencia at 28-day intervals for six months or until the arthritis flared up, or a placebo given on the same schedule.

Just over half (53 percent) of patients on the placebo and 20 percent of those on Orencia experienced an exacerbation of their condition. The odds of a flare-up in patients on Orencia were only 31 percent of that for patients on the placebo. Side effects were similar.

According to the Arthritis Foundation, juvenile idiopathic arthritis is a family of diseases involving chronic joint inflammation. Current drugs seem to fall short of what's needed, with up to 85 percent of children expected to relapse.

The study was conducted by researchers at the Istituto G Gaslini Pediatria II, Largo Gaslini, in Genova, Italy, and was published online in The Lancet.

An accompanying commentary questioned the design of the study, suggesting that it might overestimate the benefit of the drug while understating its side effects.

More information

The Arthritis Foundation   has more on juvenile arthritis.

(HealthDay News) - Flat feet may pose few or no problems for some adults. But for others, flat feet can cause pain that makes standing or moving difficult.

The American Academy of Orthopaedic Surgeons says you should see your doctor if flat feet are causing any of these conditions:

• Feet that tire easily, or become painful after standing for long periods.
• Problems standing on your toes, or moving your heel or the middle of your foot.
• Pain in the heel or arch, or swelling along the inside of the foot.
• Inability to exercise or play sports because of foot pain.
• Foot pain and rheumatoid arthritis (RA). About half of people with RA develop a worsening flat-foot deformity.