Cocoa may boost memory in older adults
A new study has determined that certain compounds found in cocoa may help reverse memory decline in older adults.
Previous animal studies have found that flavanols–a kind of antioxidant–found in cocoa beans may improve connections made in the brain region called the dentate gyrus, which plays a critical role in learning and memory.
In the new study, scientists from Columbia University Medical Center focused on whether cocoa flavanols could have a similar effect in humans and help improve age-related memory decline. They recruited 37 healthy adults between the ages 50 and 69, who took part in a three-month study. Some of the adults were asked to follow a low-flavanol diet, consuming 10 mg of flavanols a day. The other adults were asked to follow a high-flavanol diet, consuming 900 mg of flavanols a day. All participants received their dose of flavanols by drinking the same cocoa drink.
The researchers also assessed the participants’ brain function at the beginning and at the end of the study, through the use of a brain imaging technique as well as through memory tests.
The results of the study, published in Nature Neuroscience, showed that the participants who followed the high-flavanol diet performed better on the memory tests than did the participants who followed the low-flavanol diet. The high-flavanol group also showed improved function of their dentate gyrus.
The study’s findings suggest that cocoa flavanols may help improve memory in older adults, although researchers warned that consuming chocolate will not lead to the same effects found in the study, as chocolate is processed and does not contain the same levels of cocoa flavanols found in the drink used for the research. The researchers said they will conduct larger studies to determine whether their findings can be replicated.
A killer smog: Oct. 27, 1948
The residents of Donora, a small mill town along the Monongahela River in western Pennsylvania, aren’t much worried when a thick fog traps air pollution from the local zinc smelting plant and steel mills over the city. They’re used to polluted air, and while the acrid yellow smoke burns eyes and throats, people go to work and kids head off to school.
But the pollution, which contains unusually high levels of sulphuric acid, carbon monoxide and fluorine, never dissipates, and by the next day, doctors and health officials are warning anyone with respiratory conditions to get out of town. Unfortunately, the smoke is so thick that it’s nearly impossible to drive.
Not only are the hospitals soon overflowing, but firefighters with oxygen tanks begin going door to door. Many residents make a point of calling every one of Donora’s eight physicians, hoping that will get a doctor to their houses sooner.
People start getting very sick. Over the next few days, 20 will die and almost half the town’s 14,000 residents will need treatment. Almost 800 animals also die. Still, it takes four days for local doctors to convince the owners of the smelting plant to shut it down temporarily. As it turns out, that same day, Halloween morning, a rainstorm finally clears the air.
Eventually, a local group called the Society for Better Living sued the Zinc Works. Its owners agreed to make a relatively small cash payment, but according to the agreement, the company was absolved off all responsibility for the deaths and illnesses caused by the smog.
The U.S. Public Health Service released its own findings in 1949. It concluded that a temperature inversion—where cold air is held close to the Earth’s surface by warmer air above it—was responsible. The incident, it said, was a “freak of nature” and an “act of God.”
Still, the disaster, for the first time, made Americans aware of just how dangerous air pollution could be. In 1955, Congress passed the Air Pollution Control Act, the first federal legislation that recognized pollution as a problem. That was followed by the Clean Air Act in 1963, the first federal law to set standards for air quality. And then, in 1970, President Richard Nixon signed an even tougher Clean Air Act, one that established the Environmental Protection Agency and gave it the authority to enforce air quality standards.
By then, though, Donora’s smelting plant had closed. So had two mills operated by U.S. Steel. Property values plummeted and people moved away. Donora’s population is now less than half of what it was that grim late October week back in 1948.
Six years ago, to commemorate the 60th anniversary of the tragedy, the Donora Smog Museum opened in a storefront on a downtown street. The sign out front carried the phrase, “Clean air started here.”
More slices of history
Sun exposure helps prevent obesity, diabetes in mice
Moderate sun exposure may help prevent the development of obesity and diabetes, according to new animal research.
Scientists from Telethon Kids Institute in Perth, Australia tested the effects of sunlight on mice after feeding them a high-fat diet in order to trigger obesity and diabetes. The mice were then exposed to moderate levels of UV radiation.
The researchers found that after the UV exposure, the mice showed reduced weight gain and fewer indications of diabetes, such as high blood sugar levels and insulin resistance.
The researchers then analyzed whether the effects of UV exposure were due to vitamin D. However, they found that the results of the study was actually due to nitric oxide, which is a compound that the skin releases after being exposed to the sun.
The study’s findings, published in the journal Diabetes, suggest that moderate exposure to sunlight, in addition to a healthy diet and exercise, may help prevent obesity and diabetes, which have beengrowing problems for American children in recent years. Researchers noted, however, that human studies are needed before any clear conclusions can be reached about the effect of sunlight in fighting obesity.
Cancer-killing cells made in lab
Scientists from Harvard Medical School have found a way to fight brain cancer cells using genetically engineered stem cells, a discovery which they say could eventually lead to a new line of cancer therapies and increased cancer survival rates.
In previous trials, researchers have tested stem-cell-based therapy for cancer but were unable to target cancer cells without also harming normal, healthy cells.
In the new study, the researchers tested a different approach, using mice with brain tumors. First, they genetically engineered stem cells that were capable of secreting cancer-killing toxins. Next, they removed the tumors from the mice, surrounded the stem cells in gel and placed them at the site where the tumors had been.
Researchers found that the method was successful in killing the cancer cells. Additionally, neither the stem cells nor normal, healthy cells were harmed.
The findings of the study, published in the journal Stem Cells, could signify the beginning of a new line of research into stem-cell-based cancer therapies, the researchers said. They said they plan to conduct further animal studies before testing the therapies in human clinical trials.