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PLOS One
PLOS One

Building a Puking Robot—For Science

PLOS One
PLOS One

As the passengers of many a cruise ship can attest, Norovirus is a nasty illness. When people come into contact with it—via someone else who has norovirus; by eating contaminated food or water; or by touching a surface with norovirus particles on it—and are infected, the linings of their stomachs or intestines (or both!) become inflamed in something called acute gastroenteritis. First comes the stomach pain and nausea, and then the projectile vomiting and diarrhea, which bring billions of new noroviruses into the world. That number is staggering considering the fact that just 18 particles of the virus are enough to make a person ill, and the amount of virus particles that can fit on the head of a pin can infect at least 1000 people.

Norovirus, according to Carl Zimmer at National Geographic, has “Olympic-level feats of transmission.” Each year, as many as 21 million people come down with norovirus in the United States, and between 570 and 800 die. So naturally, scientists are very interested in determining just how the virus spreads—and they're building vomiting machines to figure it out.

Vomiting Larry at the Health and Safety Laboratory in Derbyshire, England, is one; another, built by researchers at North Carolina State University, was a key part of a study released this week in PLOS One.

This machine, which was built at one-quarter human size, is equipped with tubes that stand in for the esophagus and mouth; a pressurized simulated stomach; valves, pistons, and pumps to create vomiting; and, of course, a sad clay face that perfectly shows what it’s like to have norovirus. (That’s not all the mask is good for—according to Science News, it “provides weight to bend the throat down, simulating the flexed neck of a heaving human.”)

During projectile vomiting, particles of vomit—and the noroviruses they carry—become aerosolized and land on surfaces, where they’re hard to eradicate (according to Zimmer, norovirus “can survive freezing and heating and cleaning with many chemical disinfectants”). In this study, scientists were interested in both demonstrating the aerosolization and figuring out just how much of the virus was present in those airborne particles—a particularly tough challenge, considering that norovirus can’t be cultivated in a lab. 

The scientists created two “simulated vomitus matrices”—one with high viscosity, for which they used vanilla Jell-O pudding, and one with low viscosity, which was made with pre-gelatinized starch and simulated human saliva—and loaded them up with high and low concentrations of a norovirus stand-in called MS2. The scientists inserted 13.1 mL of the solutions into the vomiting machine’s stomach chamber and expelled it at various pressures that simulated vomiting and coughing.

After running the experiment, the scientists discovered that every vomiting trial led to aerosolization of the virus, ranging from “as few as 36 and as many as over 13,000 virus particles,” according to Science News.

Compared to the amount of virus in the vomit—most of which ended up at the bottom of the puking chamber—“the degree of aerosolization was rather minimal (<0.01 percent),” the scientists write. “However, based on human NoV infectious dose and estimated virus concentrations in vomitus, even these small percentages of aerosolization would likely result in significant disease risk.”

The higher the pressure of the vomit, the more noroviruses were aerosolized—but not always by a statistically significant amount. “This was partially due to the large standard deviations in the measurements, suggesting high variability in degree of virus aerosolization during vomiting,” the scientists write. “This implies that even a relatively minor vomiting event may have public health significance.”

Given all of this information, you might be asking yourself: Is there any way to prevent norovirus? The CDC recommends thoroughly washing not just your hands, but also fruits and vegetables, and thoroughly disinfecting surfaces with a bleach solution (5 to 25 tablespoons of bleach per gallon of water should do the trick). Keep sick people away from your food—and if you’re unlucky enough to get sick, don’t prepare any food yourself.

[h/t Science of Us]

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Emery Smith
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Stones, Bones, and Wrecks
The 'Alien' Mummy Is of Course Human—And Yet, Still Unusual
Emery Smith
Emery Smith

Ata has never been an alien, but she's always been an enigma. Discovered in 2003 in a leather pouch near an abandoned mining town in Chile's Atacama Desert, the tiny, 6-inch mummy's unusual features—including a narrow, sloped head, angled eyes, missing ribs, and oddly dense bones—had both the “It's aliens!” crowd and paleopathologists intrigued. Now, a team of researchers from Stanford University School of Medicine and UC-San Francisco has completed a deep genomic analysis that reveals why Ata looks as she does.

As they lay out in a paper published this week in Genome Research, the researchers found a host of genetic mutations that doomed the fetus—some of which have never been seen before.

Stanford professor of microbiology and immunology Garry Nolan first analyzed Ata back in 2012; the mummy had been purchased by a Spanish businessman and studied by a doctor named Steven Greer, who made her a star of his UFO/ET conspiracy movie Sirius. Nolan was also given a sample of her bone marrow; his DNA analysis confirmed she was, of course, human. But Nolan's study, published in the journal Science, also found something very odd: Though she was just 6 inches long when she died—a typical size for a midterm fetus—her bones appeared to be 6 to 8 years old. This did not lead Nolan to hypothesize an alien origin for Ata, but to infer that she may have had a rare bone disorder.

The current analysis confirmed that interpretation. The researchers found 40 mutations in several genes that govern bone development; these mutations have been linked to "diseases of small stature, rib anomalies, cranial malformations, premature joint fusion, and osteochondrodysplasia (also known as skeletal dysplasia)," they write. The latter is commonly known as dwarfism. Some of these mutations are linked to conditions including Ehlers-Danlos syndrome, which affects connective tissue, and Kabuki syndrome, which causes a range of physical deformities and cognitive issues. Other mutations known to cause disease had never before been associated with bone growth or developmental disorders until being discovered in Ata.

scientist measures the the 6-inch-long mummy called Ata, which is not an alien
Emery Smith

"Given the size of the specimen and the severity of the mutations … it seems likely the specimen was a pre-term birth," they write. "While we can only speculate as to the cause for multiple mutations in Ata's genome, the specimen was found in La Noria, one of the Atacama Desert's many abandoned nitrate mining towns, which suggests a possible role for prenatal nitrate exposure leading to DNA damage."

Though the researchers haven't identified the exact age of Ata's remains, they're estimated to be less than 500 years old (and potentially as young as 40 years old). Genomic analysis also confirms that Ata is very much not only an Earthling, but a local; her DNA is a nearest match to three individuals from the Chilote people of Chile.

In a press statement, study co-lead Atul Butte, director of the Institute for Computational Health Sciences at UC-San Francisco, stressed the potential applications of the study to genetic disorders. "For me, what really came of this study was the idea that we shouldn't stop investigating when we find one gene that might explain a symptom. It could be multiple things going wrong, and it's worth getting a full explanation, especially as we head closer and closer to gene therapy," Butte said. "We could presumably one day fix some of these disorders."

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iStock
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Health
Just Two Cans of Soda a Day May Double Your Risk of Death From Heart Disease
iStock
iStock

If you've been stocking your refrigerator full of carbonated corn syrup in anticipation of warmer weather, the American Heart Association has some bad news. The advocacy group on Wednesday released results of research that demonstrate a link between consumption of sugary drinks—including soda, fruit juices, and other sweetened beverages—and an increased risk of dying from heart disease.

Study participants who reported consuming 24 ounces or more of sugary drinks per day had twice the risk of death from coronary artery disease of those who averaged less than 1 ounce daily. There was also an increased risk of death overall, including from other cardiovascular conditions.

The study, led by Emory University professor Jean Welsh, examined data taken from a longitudinal study of 17,930 adults over the age of 45 with no previous history of heart disease, stroke, or diabetes. Researchers followed participants for six years, and examined death records to determine causes. They observed a greater risk of death associated with sugary drinks even when they controlled for other factors, including race, income, education, smoking habits, and physical activity. The study does not show cause and effect, the researchers said, but does illuminate a trend.

The study also noted that while it showed an increased risk of death from heart disease, consumption of sugary foods was not shown to carry similar risk. One possible explanation is that the body metabolizes the sugars differently: Solid foods carry other nutrients, like fat and protein, that slow metabolism, while sugary drinks provide an undiluted influx of carbohydrates that the body must process.

The news will likely prove troublesome for the beverage industry, which has long contended with concerns that sugary drinks contribute to type 2 diabetes and tooth decay. Some cities, including Seattle, have introduced controversial "soda tax" plans that raise the sales tax on the drinks in an effort to discourage consumption.

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