Science Sunday: Crohn’s Disease, Mayan Crops, and Senior Sex

Two primary human inflammatory bowel diseases — Crohn’s disease and ulcerative colitis — are apparently the result of the imbalances of two different microbiotas in small intestine.

Work by Daniel Frank of the University of Colorado-Boulder and colleagues found that while both diseases appear to be caused abnormal states of microbiota, the depleted subsets of the bacteria were different for each.Their paper says:

Patient stratification by gastrointestinal microbiota provides further evidence that Crohn’s disease represents a spectrum of disease states and suggests that treatment of some forms of inflammatory bowel disease may be facilitated by redress of the detected microbiological

The paper appears in the August 21, 2007 Proceedings of the National Academy of Sciences.

CU team finds ancient manioc field
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Digging through volcanic ash in an ancient Central American village, a team of CU researchers found the first evidence of manioc cultivation in the New World, dating from an estimated 1,400 years ago.

Loma Calder volcano erupted in about 600 A.D., burying the town of Ceren in modern-day El Salvador under a thick layer of ash. the well-preserved community, which CU Prof. Payson Sheets has been excavating since 1978, yielded the first evidence of manioc cultivation from an archaeological dig, Sheets says.

Manioc is a cassava, a long root plant that is a still staple of tropical American cooking. It’s the source of tapioca and an alcoholic drink called cassiri. The discovery opens a window into the agricultural technology that helped create the powerful empires of the classic Mayan civilization, which lasted from about 250 to 900 A.D.

Photo by Jim Scott, University of Colorado
CU-Boulder anthropology Professor Payson Sheets maps ancient household at site of Ceren in El Salvador.

“We have long wondered what else the prehistoric Mayan people were growing and eating besides corn and beans, so finding this field was a jackpot of sorts for us,” Sheets says. “Manioc’s extraordinary productivity may help explain how the Classic Maya at huge sites like Tikal in Guatemala and Copan in Honduras supported such dense populations.”

The research was funded by the National Geographic Society.

Senior sex

Sexual activity in older adults declines only slight from the late 50s to the early 70s, according to a British survey of sexual behavior in older people.

Data from the University of Chicago’s National Social Life, Health and Aging Project (NSHAP), presented in the August 23, 2007, issue of the New England Journal of Medicine, showed that many men and women remain sexually active-participating in vaginal intercourse, oral sex and masturbation-well into their 70s and 80s.

The survey also found that sexual activity was closely tied to overall health, which was even more important than age. As health declined steadily after the early 70s, so did the prevalence of sexual activity, particularly for women. Among those who remained sexually active, nearly half reported at least one sexual problem, such as lack of desire (43 percent of women), vaginal dryness (39 percent of women) or erectile dysfunction (37 percent of men).