Pain is more than a symptom of osteoarthritis; it's a damaging part of the disease itself, says a new study.

Researchers at the University of Rochester Medical Center say they've discovered that pain signals originating in arthritic joints, and the biochemical processing of those signals as they travel to the spinal cord and brain, appear to worsen and expand the disease.

"Until relatively recently, osteoarthritis was believed to be due solely to wear and tear, an inevitable part of aging," said Stephanos Kyrkanides, an associate professor of dentistry who headed the study, which focused on the jaw joint — a common site of arthritic pain.

But Kyrkanides and colleagues found that even before arthritis sufferers consciously feel pain signals from afflicted joints, those traveling signals are inducing biochemical changes that may eventually lead to arthritic inflammation in other joints.

The discovery, however disheartening, may provide a new method for treating arthritis by blocking specific pain receptors, said Kyrkanides.

Osteoarthritis is the most common form of the disease, with an estimated 20 million adult sufferers in the United States.

BODY OF KNOWLEDGE

Roughly 1,000 simple cells can fit on the head of a pin. A typical human cell is about 10 micrometers across, or 0.0003937007874015748 of an inch. So it takes a lot of cells to make a person. Estimates range up to 100 trillion per person, though the majority of these cells are actually bacterial, not human.

NUMBER CRUNCHER

A slice of Papa John's 14-inch thin crust pizza with "the works" (120 grams) contains 280 calories, 126 from fat. That's 14 percent of the recommended total fat intake for a 2,000-calorie daily diet.

It also contains 25 milligrams of cholesterol (8 percent); 670mg of sodium (28 percent); 24 grams of total carbohydrates (8 percent); 2g of dietary fiber (8 percent); 3g of sugar and 12g of protein.

MEDTRONICA

Bluebook for the control of infectious diseases

www.health.vic.gov.au/ideas/bluebook

The other bluebook (about used-car values) is informative. This bluebook, produced by the Australian government, is informative and scary. It's mostly aimed at public health officials, but you can learn many things about diseases such as anthrax, diphtheria and the plague, and what you should do during an outbreak.

STORIES FOR THE WAITING ROOM

The activist group People for the Ethical Treatment of Animals' recent suggestion that Ben & Jerry's replace cow's milk with, um, human breast milk poses questions beyond how the Vermont-based ice cream maker would find the millions of gallons required to make frozen delights like Cherry Garcia and Phish Food.

There's also the issue of potential health risks. Diseases like tuberculosis and HIV can be transmitted through human breast milk, along with some drugs and antibiotics, none of which makes anybody's list of favorite secret ingredients.

PHOBIA OF THE WEEK

Hyelophobia — fear of glass

OBSERVATION

I think scientists should stop wasting valuable resources trying to cure cancer and focus on more important issues, like keeping me from drooling in my sleep.

— Comedian Bill Hewins

To find out more about Scott Lafee and read features by other Creators Syndicate writers and cartoonists, visit the Creators Syndicate website at www.creators.com.

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