BOSTON, Oct. 14 (UPI) -- Harvard University scientists have asked the school for permission to clone human embryos to create stem cells for medical research.

If approved, they would be the first researchers at a U.S. university to attempt the procedure, USA Today said Thursday.

Dr. Doug Nelton, a molecular embryologist, and his colleagues at the Harvard Stem Cell Institute said they hope to create stem cells for use in studying juvenile diabetes and diseases such as Alzheimer's and Parkinson's.

Another group at the Harvard-affiliated Children's Hospital, working on blood diseases such as leukemia, also plans to attempt the creation of stem cell lines from cloned human embryos but has not yet applied for permission.

A U.S.-based company, Advanced Cell Technology, announced it had created the first cloned human embryo in late 2001, but the effort was seen as only partially successful.

Nerve damage possible in weight surgery

ROCHESTER, Minn., Oct. 14 (UPI) -- So-called "stomach stapling" or gastric bypass surgery for weight reduction can lead to nerve damage, researchers say.

A "significant" number of patients who undergo the procedure develop peripheral neuropathy, damage to the body's nerves outside of the brain and spinal cord, researchers at the Mayo Clinic say in a report.

The Mayo investigators found that 16 percent of weight-reduction surgery patients they studied developed a peripheral neuropathy.

The development of nerve damage is associated with malnutrition, the report says, and therefore largely preventable with proper nutritional care.

"Surgeons who do weight-reduction surgery and the general public should be aware that nerve damage is a frequent consequence of the surgery," says Dr. James Dyck, Mayo Clinic neurologist and lead investigator in this study.

The report will be presented at the American Medical Association Science Reporters Conference on Oct. 14 and published in the Oct. 26 issue of the journal Neurology.

'Portion control' seen key to weight loss

AKRON, Ohio, Oct. 14 (UPI) -- The greatest factor leading to weight loss in an obesity study was not what one ate but how much -- the key being "portion control."

That was the deduction of a 24-month federally-funded study led by Summa Health System researchers in Akron, Ohio, and published in the journal Obesity Research.

"Although we saw similar patterns of weight loss related to reduced dietary fat consumption, increased fruit and vegetable consumption, increased physical activity and increased planned exercise, the target behavior that induced the greatest weight loss was portion control," said Dr. Everett E. Logue, the lead researcher.

The study found that 38 percent of obese patients who consistently spent two years practicing food portion control lost 5 percent or more of their baseline weight.

Conversely, they concluded that 33 percent of patients who did not consistently practice portion control gained 5 percent or more of their baseline weight.

Double sun risk for blondes, redheads

NEW HAVEN, Conn., Oct. 14 (UPI) -- The pigment-producing melanin in blond and redheaded people magnifies ultraviolet rays, heightening the risk of skin cancer in the already susceptible group.

Douglas Brash, principal investigator and professor of therapeutic radiology, genetics and dermatology at Yale School of Medicine said he had been curious why people with dark hair and fair skin were not as vulnerable to skin cancer as fair skinned blondes and redheads.

Melanin filters out UV radiation, but the melanin in hair follicles, particularly in light hair, actually increases the sun damaging effects of UV rays and causes cell death in the hair follicle, Brash said.

Using mice engineered with pigmentation for yellow or black hair, as well as albino mice with no pigment at all, researchers irradiated the mice with UV rays that are about the same as what reaches humans.

The cell death was concentrated around the hair follicles, which are the only location of melanin in mice. Dying cells were particularly pronounced in the yellow-haired mice and was absent in albinos.