Disease found in mummy

An Inca girl who lived 500 years ago suffered from a bacterial lung infection just before she died, report scientists who have examined her mummy.

The girl, thought to be 15, was sacrificed by the Andean Inca at the summit of Llullaillaco, a nearly 6,700-meter volcano in the province of Salta, Argentina, said Angelique Corthals, a forensic anthropologist at the City University of New York. The girl had a large sore on one leg, leading Dr. Corthals to believe she may have been unwell when she was buried, alive but unconscious.

Dr. Corthals and her colleagues used a technique called shotgun proteomics to compare proteins in the mummy against large databases of the human genome. The mummy's protein profile fit that of someone with a chronic respiratory infection, said Liliana M. Davalos, an evolutionary biologist at Stony Brook University in New York and another author of the study, which is reported in the journal PLoS One.

"This is the first time it has been done on an ancient mummy," Dr. Davalos said. "It's now done routinely on cancer patients and has many human disease applications, but it hadn't been applied in archaeological work."

Argentine researchers discovered the mummy, along with those of two other sacrificed children, in 1999.

"The girl actually had gray hair, so I think they knew their fate," Dr. Corthals said. The mummies are on view at the Museum of High Mountain Archaeology in Salta.

Sindya N. Bhanoo

A benefit of late pregnancy

The older a woman is when she gives birth, the lower her risk for endometrial cancer, a study reports.

A large team of researchers, led by V. Wendy Setiawan, an assistant professor of preventive medicine at the University of Southern California, pooled data from 17 studies that included 8,671 cases of endometrial cancer and 16,562 controls. After adjusting for known risks, the researchers found that women who had their last babies after age 40 had a 44 percent reduced risk of endometrial cancer, compared with women who had their babies before age 25.

Even later in life, women who gave birth after age 40 remained at decreased risk. By age 70, these women were still 33 percent less likely to have endometrial cancer than those who gave birth before age 25.

The reasons for the finding, published in July in The American Journal of Epidemiology, are unclear. It may be that women who can get pregnant at a later age have a healthier endometrium to begin with, or that pregnancy allows women to shed precancerous cells likelier to be present with increasing age.

"There is some protective mechanism here, at least for this type of cancer," Dr. Setiawan said. "Once we find out what the mechanism is, then we can understand how this develops and we can try to prevent it."

Nicholas Bakalar

French worm goes Irish

An earthworm species rarely seen outside the Aquitaine region of southwestern France is thriving more than 960 kilometers to the north, across the sea in Ireland, a new study reports.

The earthworm's new habitat, on an urban farm in Dublin, was discovered by Olaf Schmidt, a biologist at University College Dublin and an author of the study.

"What is really interesting about these worms is that there are about 25 species restricted to a small area in the southwest of France," he said. "None have moved outside this area, and suddenly we found them in a routine survey of farms in Dublin."

He and his colleague Carol Melody, also of University College Dublin, report their findings in the journal Biology Letters.

The worm may have arrived with imported plants. The species, Prosellodrilus amplisetosus, is coexisting with 30 other earthworm species found in Ireland, Dr. Schmidt said.

"This new worm eats a different carbon and nitrogen fraction in the soil," he said. "It could be that they will contribute to the maintenance of the soil structure and nutrients."

The mean yearly temperature in Aquitaine is about three degrees Celsius higher than that in Dublin. But globally, temperatures are rising.

"It's very tempting to speculate that they only survive here now because of an increase on average of temperatures," Dr. Schmidt said.

Sindya N. Bhanoo

(China Daily 08/12/2012 page11)