Take a bite of chitin
Chitin is a dietary fiber found abundantly in the exoskeletons of insects and crustaceans; the shells of crabs and lobsters, for example. New research suggests that chomping down on chitin (crustaceans, if not insects) may be good for digestion, triggering an immune response that is linked to less weight gain, reduced body fat and resistance to obesity.
Researchers found that a particular arm of the immune system is involved in chitin digestion. Stomach distention after chitin ingestion activates an innate immune response that triggers stomach cells to ramp up production of enzymes, known as chitinases, that break down chitin. One benefit: Increased metabolic activity and reduced calorie consumption.
Of course, the prospect of eating the exoskeletons of creatures is probably going to reduce calorie consumption before the first bite.
Vaccine hesitancy goes to the dogs
Researchers analyzed a nationally representative sample of adults in the United States and found that more than half of people who own dogs expressed some level of canine vaccine hesitancy. In other words, they were skeptical about vaccinating their pets against rabies and other diseases.
Specifically, an estimated 45 percent of U.S. households own a dog; according to the survey results, nearly 40 percent of dog owners believe that canine vaccines are unsafe, more than 20 percent believe these vaccines are ineffective and 30 percent consider them to be medically unnecessary.
Approximately 37 percent of dog owners also believe that canine vaccination could cause their dogs to develop autism spectrum disorder, even though there is no scientific data that validates this risk for animals or humans. ASD can occur in dogs, but it’s called canine dysfunctional behavior and its cause is unknown.
Body of knowledge
There are an estimated 480 million alveoli in an average pair of adult human lungs. These tiny air sacs take in oxygen and expel carbon dioxide. They are where oxygen is transferred from the lungs to the bloodstream.
Doc talk
Counts
Get me that. Stat!
More than one-third of U.S. households with teens own firearms and more than two-thirds of these owners store at least one gun unlocked and/or loaded, according to a University of Michigan study.
Best medicine
Recent studies show that patients who have a cold feel better on Saturdays and Sundays. Evidence suggests a weekend immune system.
Observation
“Many a health has been ruined by drinking to the health of others.”
Medical history
This week in 1997, American biology professor Stanley B. Prusiner won the Nobel Prize for medicine for discovering “prions,” described as “an entirely new genre of disease-causing agents.” The name means “proteinaceous infectious particle.” Prions cause brain diseases such as bovine spongiform encephalopathy (“mad cow disease”); the human variant of the disease, called Creutzfeldt–Jakob disease; kuru among some peoples in New Guinea; and scrapie in sheep and goats. Prions are too small to be seen with normal microscopy. They are self-replicating but contain no nucleic acid. Prions are highly resistant to destruction or denaturation by common chemical and physical agents such as disinfectants, formalin, heat, UV or ionizing radiation. Incineration of infected tissues requires a temperature of at least 900 degrees Fahrenheit for four hours.
Phobia of the week
Self-exam
Q: What are the three layers of skin?
A: From outer to inner: epidermis, dermis and hypodermis.
Bonus question: What do you call the outer layer of an animal or plant?
A: Integument, which encomes not just skin, but hair, nails and glands.
Epitaphs
“Leave for her a red young rose.Go your way, and save your pity;She is happy, for she knowsThat her dust is very pretty.”
LaFee is vice president of communications for the Sanford Burnham Prebys research institute.
