Research

Bad link: Leptin, the so-called "fat hormone," promotes growth of breast cancer cells, according to a new study in the November issue of the Journal of the National Cancer Institute.

Obesity long has been identified as a risk factor for breast cancer, but scientists don't know what linked the two conditions. Researchers at the University of Minnesota identified leptin as the link.

"These findings may explain why weight gain, which is accompanied by higher than expected leptin concentrations, also has been associated with increased breast cancer risk," said Dr. Margot Cleary, lead author.

Researchers found that cancerous breast cells increased 150 percent when leptin was present, compared with 50 percent for normal breast cells.

It was also found that only breast cancer cells exposed to leptin formed tumors, supporting the idea that the hormone promotes tumor growth and development and the link between obesity and breast cancer.

Lack of leptin or its receptors was associated with lack of breast tissue development in mice.

Hot news<p> Barriers: Researchers at the University of Michigan Health System are looking for ways to reduce heart disease and diabetes deaths among people with spinal cord injuries.

Nutrition and exercise would go a long way toward reducing risks, researchers say, but health care providers need to find a way to guide patients past physical and psychological barriers.

A survey of patients with spinal cord injuries showed that while three-quarters of respondents want to exercise, less than half do.

Many respondents cited lack of motivation and energy for their inactivity, the same reasons cited by adults without spinal cord injuries.

But about half cited concerns that staff at fitness centers wouldn't know how to work with people with spinal cord injuries and a sizable minority felt their physical condition prevented them from exercising or that exercise would make their condition worse.

And fewer than half had been encouraged by their doctors to exercise.

Tips

Safety: If you're getting out the ladder to hang holiday lights, remember these safety tips from the American Academy of Orthopaedic Surgeons:

• Inspect the ladder for loose screws, broken rungs, slick spots, etc., before using it.

• Set the ladder on a firm, stable surface. Make sure it won't hit electrical wires, tree limbs or other hazards.

• Don't use the top step or pail shelf as a seat.

• Move the ladder closer to your work; stretching could result in loss of balance and falls.

• Wear proper shoes.

• Ask someone to hold the ladder while you work.

Siting

Calculated: Check out www.caloriecontrol.org for a variety of online calorie counters.

Contact Peggy O'Farrell by phone, 768-8510; fax, 768-8330, or e-mail, pofarrell@enquirer.com