A Boise State University study has shed new light on how proteins interact, or bind, with one another in tissues. The new information could help scientists with tissue engineering and strengthening efforts to treat cartilage damage and degeneration by diseases such as osteoarthritis, which affects more than 20 million Americans and is the most common type of arthritis.

Cartilage is central to proper growth and articulation of the joint. The cartilage tissue is composed of chondrocytes and a dense extracellular matrix, which in turn is composed of water, proteoglycans and collagens.

The Boise State biologists found that a protein called collagen XI interacts with specific proteins in the part of the tissue that provides structural support to the cell. Collagen XI is one of the few proteins that is known to prevent arthritis, and when it is mutated or absent, the individual will develop arthritis early in life. Even knowing this, the progression of the disease is still poorly understood by scientists. This lack of understanding prevents the development of effective treatments.

"Knowing which proteins collagen XI binds to could have significant implications in helping clinicians monitor cartilage health as well as diagnose and treat debilitating diseases like arthritis," said study coauthor Julia Oxford, biology professor and director of the Biomolecular Research Center. "Understanding these complex gene families will make major improvements in the quality of life for those dealing with a broad spectrum of arthritic syndromes. If we know what the structure should look like, we can look for changes caused by disease and figure out ways to stop and treat it."

The study appears online in the journal Proteomics.

To conduct the research, Boise State scientists studied tissue and used affinity chromatography and mass spectrometry to identify proteins that can interact with collagen XI. They found several molecules and cellular proteins that interact with it directly or indirectly, including proteoglycans and matricellular molecules, both of which play a significant role in tissue integrity and tissue development.

Oxford said based on their findings, collagen XI has the potential to be used as a diagnostic tool to predict which individuals are predisposed to the development of osteoarthritis.

Suggestions for easing the discomfort :

(HealthDay News) -- Sitting at a desk and working at a computer all day can be painful for someone with arthritis.

The Arthritis Foundation offers these suggestions to ease arthritis pain and stiffness while you're at work:

• Take regular breaks every 20 minutes to 30 minutes, getting up to stretch and move around.
• Make sure your desk chair fits you well, and sit with your feet flat on the floor.
• Set up your computer screen so it's level with your eyes.
• Place papers in a document holder so they're easier to see without straining.
• If your chair lacks lumbar support, use a rolled-up towel or small pillow to provide better support for your lower back.

Liz Smith has six kids, and her fifth child has juvenile arthritis.

The first signs of arthritis in Emily, now 18, appeared when she was just 2½ years old, said Smith, who lives in Burke, Va. "She slipped in a swimming pool and had a swollen ankle that never got better," her mother said. "That was the beginning of all of it."

For several months, the family agonized over whether Emily's ankle was sprained or broken, but then other joints started swelling. Her middle finger on one hand swelled to the point that her older brothers teased her about flipping them off.

Emily underwent a series of bone scans and blood tests to look for leukemia, bone infection or bone cancer -- "fun stuff like that," Smith said. "Once all of that was ruled out, the folks at the hospital said, 'We think she needs to see a rheumatologist.'"

The specialist checked Emily's health records and gave her an examination, and in short order determined that the young girl had juvenile arthritis. Her family received the diagnosis just before her third birthday.

"For us, the diagnosis was a relief," Smith recalled. "We didn't quite understand we were in this for the long haul. It took some time for us to come to grips with that. The dream changes from the hope that one day this will all be gone and you can forget about it, to hoping that she is able to live a full and productive life doing all of the things she wants to do."

Emily has taken arthritis medication ever since the diagnosis. "The one attempt to get her off meds was disastrous," Smith said of the effort about a month before Emily's seventh birthday. "It lasted three weeks. We had these three wonderful, medication-free weeks, and then she woke up one morning and couldn't get out of bed on her own. And then it got worse. It got a lot worse before it got better. It took a stronger medication cocktail and several years for her to get where she is today."

Emily currently takes a combination of the gold-standard arthritis drug methotrexate, a newer biologic drug (Orencia) and a prescription non-steroidal anti-inflammatory drug. "She's been fairly lucky," her mother said. "She's done pretty well for the last few years, in terms of not having any side effects."

And Emily has not let arthritis deter her passions, her mother added. "She has been able to try everything she's wanted to do," Smith said. "When she was a very little girl, she was enthralled by the summer Olympics, and she decided she was going to be a gymnast. That fell by the wayside for a while, but eventually she was able to take gymnastic classes. At least she got to participate in it."

Smith recalled another time, during Emily's freshman year in high school, when she came to her parents and declared that she was joining the track team. "I said, 'A couple days ago you couldn't get down the stairs. How are you going to run?' She said, 'I'm not going to be a runner,'" Smith recalled. "She was going to pole vault."

Emily's parents said she could if her doctor allowed it, and then were flabbergasted when he gave it the OK.

"She pole vaulted through high school," Smith said. "She did OK. She cleared six feet, and she had fun and she was able to participate on the team."

Pole vaulting and arthritis collided only when doctors wanted to install a port to make her biologic treatments easier to deliver.

"She told the surgeon if she couldn't pole vault with the port, then the port would have to wait," Smith said. The doctors said the port would not interfere with her pole vaulting, so she went ahead with the procedure.

"She has amazing spirit," her mother said. "She's a very strong and confident and determined young lady. She still has bad days, but she's doing really well. When I stop and think what her life would be without the benefit of these newer medications, those bad days don't seem so bad."

Now in her freshman year in college, Emily wants to pursue a bachelor's degree in nursing. "It's because of the nurses who helped care for her that she was able to make this decision," Smith said.

"I think there are days, but they are few and far between, where her arthritis might weigh on her," Smith concluded. "But for most of the time, it is what it is."

In the largest study to date of the Arthritis Foundation's Tai Chi program, participants showed improvement in pain, fatigue, stiffness and sense of well-being.

Their ability to reach while maintaining balance also improved, said Leigh Callahan, PhD, the study's lead author, associate professor in the University of North Carolina at Chapel Hill School of Medicine and a member of UNC's Thurston Arthritis Research Center.

"Our study shows that there are significant benefits of the Tai Chi course for individuals with all types of arthritis, including fibromyalgia, rheumatoid arthritis and osteoarthritis," Callahan said. "We found this in both rural and urban settings across a southeastern state and a northeastern state."

Callahan will present these results on Nov. 8, at the annual scientific meeting of the American College of Rheumatology in Atlanta.

In the study, 354 participants were recruited from 20 sites in North Carolina and New Jersey. They were randomly assigned to two groups. The intervention group received the 8-week, twice-weekly Tai Chi course immediately while the other group was a delayed control group. All participants received baseline and 8-week follow-up evaluations, after which the control group also received the Tai Chi course.

To be eligible for study, participants had to have any type of self-reported, doctor-diagnosed arthritis, be 18 years old or older and able to move independently without assistance. However, they did not have to be able to perform Tai Chi standing. They were eligible for the study if they could perform Tai Chi seated, Callahan said.

Self-reports of pain, fatigue and stiffness and physical function performance measures were collected at baseline and at the eight-week evaluation. Participants were asked questions about their ability to perform activities of daily living, their overall general health and psychosocial measures such as their perceived helplessness and self-efficacy. The physical performance measures recorded were timed chair stands (which are a measure of lower extremity strength), gait speed (both normal and fast) and two measures of balance: a single leg stance and a reach test.

At the end of eight weeks the individuals who had received the intervention showed moderate improvements in pain, fatigue and stiffness. They also had an increased sense of well being, as measured by the psychosocial variables, and they had improved reach or balance, Callahan said.