A football player making a tackle during a game. (© Joe/Fotolia)
What do football superstars Tom Brady, Drew Brees, Philip Rivers, and Adrian Peterson all have in common? Last year they wore helmets that provided the poorest protection against concussions in all the NFL.
"You're only as protected as well as the worst helmet that's out there."
A Dangerous Policy
Football helmets are rated on a one-star to five-star system based on how well they do the job of protecting the player. The league has allowed players to use their favorites, regardless of the star rating.
The Oxford-trained neuroscientist Ray Colello conducted a serious analysis of just how much the protection can vary between each level of star rating. Colello and his team of graduate students sifted through two seasons of game video to identify which players were wearing what helmets. There was "a really good correlation with position, but the correlation is much more significant based on age."
"The average player in the NFL is 26.6 years old, but the average age of a player wearing a one-star helmet is 34. And for anyone who knows football, that's ancient," the brain doc says. "Then for our two-star helmet, it's 32; and for a three-star helmet it's 29." Players were sticking with the helmets they were familiar with in college, despite the fact that equipment had improved considerably in recent years.
"You're only as protected as well as the worst helmet that's out there," Colello explains. Offering an auto analogy, he says, "It's like, if you run into the back of a Pinto, even if you are in a five-star Mercedes, that gas tank may still explode and you are still going to die."
It's one thing for a player to take a risk at scrambling his own brain; it's another matter to put a teammate or opponent at needless risk. Colello published his analysis early last year and the NFL moved quickly to ban the worst performing helmets, starting next season.
Some of the 14 players using the soon-to-be-banned helmets, like Drew Brees and Philip Rivers, made the switch to a five-star helmet at the start of training camp and stayed with it. Adrian Peterson wore a one-star helmet throughout the season.
Tom Brady tried but just couldn't get comfortable with a new bonnet and, after losing a few games, switched back to his old one in the middle of the season; he says he's going to ask the league to "grandfather in" his old helmet so he can continue to use it.
As for Colello, he's only just getting started. The brain doc has a much bigger vision for the future of football safety. He wants to prevent concussions from even occurring in the first place by creating an innovative new helmet that's unlike anything the league has ever seen.
Oxford-trained neuroscientist Ray Colello is on a mission to make football safer.
(Photo credit: VCU public affairs)
"A Force Field" of Protection
His inspiration was serendipitous; he was at home watching a football game on TV when Denver Bronco's receiver Wes Welker was hit, lay flat on the field with a concussion, and was carted off. As a commercial flickered on the screen, he ambled into the kitchen for another beer. "What those guys need is a force field protecting them," he thought to himself.
Like so many households, the refrigerator door was festooned with magnets holding his kids' school work in place. And in that eureka moment the idea popped into his head: "Maybe the repulsive force of magnets can put a break on an impact before it even occurs." Colello has spent the last few years trying to turn his concept into reality.
Newton's laws of physics – mass and speed – play out graphically in a concussion. The sudden stop of a helmet-to-helmet collision can shake the brain back and forth inside the skull like beans in a maraca. Dried beans stand up to the impact, making their distinctive musical sound; living brain tissue is much softer and not nearly so percussive. The resulting damage is a concussion.
The risk of that occurring is greater than you might think. Researchers using accelerometers inside helmets have determined that a typical college football player experiences about 600 helmet-to-helmet contacts during a season of practice and games. Each hit generates a split second peak g-force of 20 to 150 within the helmet and the odds of one causing a concussion increase sharply over 100 gs of force.
By comparison, astronauts typically experience a maximum sustained 3gs during lift off and most humans will black out around 9gs, which is why fighter pilots wear special pressure suits to counter the effects.
"It stretches the time line of impact quite dramatically. In fact in most instances, it doesn't even hit."
The NFL's fastest player, Chris Johnson, can run 19.3 mph. A collision at that speed "produces 120gs worth of force," Colello explains. "But if you can extend that time of impact by just 5 milliseconds (from 12 to 17msec) you'll shift that g-force down to 84. There is a very good chance that he won't suffer a concussion."
The neuroscientist dived into learning all he could about the physics magnets. It turns out that the most powerful commercially available magnet is an alloy made of neodymium, iron, and boron. The elements can be mixed and glued together in any shape and then an electric current is run through to make it magnetic; the direction of the current establishes the north-south poles.
A 1-pound neodymium magnet can repulse 600 times its own weight, even though the magnetic field extends less than an inch. That means it can push back a magnet inside another helmet but not affect the brain.
Crash Testing the Magnets
Colello couldn't wait to see if his idea panned out. With blessing from his wife to use their credit card, he purchased some neodymium magnets and jury-rigged experiments at home.
The reinforced plastics used in football helmets don't affect the magnetic field. And the small magnets stopped weights on gym equipment that were dropped from various heights. "It stretches the time line of impact quite dramatically. In fact in most instances, it doesn't even hit," says Colello. "We are dramatically shifting the curve" of impact.
Virginia Commonwealth University stepped in with a $50,000 innovation grant to support the next research steps. The professor ordered magnets custom-designed to fit the curvature of space inside the front and sides of existing football helmets. That makes it impossible to install them the wrong way, and ensures the magnets' poles will always repel and not attract. It adds about a pound and a half to the weight of the helmet.
a) The brain in a helmet. b) Placing the magnet. c) Measuring the impact of a helmet-to-helmet collision. d) How magnets reduce the force of impact.
(Courtesy Ray Colello)
Colello rented crash test dummy heads crammed with accelerometers and found that the magnets performed equally well at slowing collisions when fixed to a pendulum in a test that approximated a helmet and head hitting a similarly equipped helmet. It impressively reduced the force of contact.
The NFL was looking for outside-the-box thinking to prevent concussions. It was intrigued by Colello's approach and two years ago invited him to submit materials for review. To be fair to all entrants, the league proposed to subject all entries to the same standard crush test to see how well each performed in lessening impact. The only trouble was, Colello's approach was designed to avoid collisions, not lessen their impact. The test wouldn't have been a valid evaluation and he withdrew from consideration.
But Colello's work caught the attention of Stefan Duma, an engineering professor at Virginia Tech who developed the five-star rating system for football helmets.
"In theory it makes sense to use [the magnets] to slow down or reduce acceleration, that's logical," says Duma. He believes current helmet technology is nearing "the end of the physics barrier; you can only absorb so much energy in so much space," so the field is ripe for new approaches to improve helmet technology.
However, one of Duma's concerns is whether magnets "are feasible from a weight standpoint." Most helmets today weigh between two and four pounds, and a sufficiently powerful magnet might add too much weight. One possibility is using an electromagnet, which potentially could be lighter and more powerful, particularly if the power supply could be carried lower in the body, say in the shoulder pads.
Colello says his lab tests are promising enough that the concept needs to be tried out on the playing field. "We need to make enough helmets for two teams to play each other in a regulation-style game and measure the impact forces that are generated on each, and see if there is a significant reduction." He is waiting to hear from the National Institutes of Health on a grant proposal to take that next step toward dramatically reducing the risk of concussions in the NFL.
Just five milliseconds could do it.
Researchers are looking to engineer chocolate with less oil, which could reduce some of its detriments to health.
Building a 3D tongue
The team began by building a 3D tongue to analyze the physical process by which chocolate breaks down inside the mouth.
As part of the effort, reported earlier this year in the scientific journal ACS Applied Materials and Interfaces, the team studied a large variety of human tongues with the intention to build an “average” 3D model, says Soltanahmadi, a lubrication scientist. When it comes to edible substances, lubrication science looks at how food feels in the mouth and can help design foods that taste better and have more satisfying texture or health benefits.
There are variations in how people enjoy chocolate; some chew it while others “lick it” inside their mouths.
Tongue impressions from human participants studied using optical imaging helped the team build a tongue with key characteristics. “Our tongue is not a smooth muscle, it’s got some texture, it has got some roughness,” Soltanahmadi says. From those images, the team came up with a digital design of an average tongue and, using 3D printed molds, built a “mimic tongue.” They also added elastomers—such as silicone or polyurethane—to mimic the roughness, the texture and the mechanical properties of a real tongue. “Wettability" was another key component of the 3D tongue, Soltanahmadi says, referring to whether a surface mixes with water (hydrophilic) or, in the case of oil, resists it (hydrophobic).
Notably, the resulting artificial 3D-tongues looked nothing like the human version, but they were good mimics. The scientists also created “testing kits” that produced data on various physical parameters. One such parameter was viscosity, the measure of how gooey a food or liquid is — honey is more viscous compared to water, for example. Another was tribology, which defines how slippery something is — high fat yogurt is more slippery than low fat yogurt; milk can be more slippery than water. The researchers then mixed chocolate with artificial saliva and spread it on the 3D tongue to measure the tribology and the viscosity. From there they were able to study what happens inside the mouth when we eat chocolate.
The team focused on the stages of lubrication and the location of the fat in the chocolate, a process that has rarely been researched.
The artificial 3D-tongues look nothing like human tongues, but they function well enough to do the job.
Courtesy Anwesha Sarkar and University of Leeds
The oral processing of chocolate
We process food in our mouths in several stages, Soltanahmadi says. And there is variation in these stages depending on the type of food. So, the oral processing of a piece of meat would be different from, say, the processing of jelly or popcorn.
There are variations with chocolate, in particular; some people chew it while others use their tongues to explore it (within their mouths), Soltanahmadi explains. “Usually, from a consumer perspective, what we find is that if you have a luxury kind of a chocolate, then people tend to start with licking the chocolate rather than chewing it.” The researchers used a luxury brand of dark chocolate and focused on the process of licking rather than chewing.
As solid cocoa particles and fat are released, the emulsion envelops the tongue and coats the palette creating a smooth feeling of chocolate all over the mouth. That tactile sensation is part of the chocolate’s hedonistic appeal we crave.
Understanding the make-up of the chocolate was also an important step in the study. “Chocolate is a composite material. So, it has cocoa butter, which is oil, it has some particles in it, which is cocoa solid, and it has sugars," Soltanahmadi says. "Dark chocolate has less oil, for example, and less sugar in it, most of the time."
The researchers determined that the oral processing of chocolate begins as soon as it enters a person’s mouth; it starts melting upon exposure to one’s body temperature, even before the tongue starts moving, Soltanahmadi says. Then, lubrication begins. “[Saliva] mixes with the oily chocolate and it makes an emulsion." An emulsion is a fluid with a watery (or aqueous) phase and an oily phase. As chocolate breaks down in the mouth, that solid piece turns into a smooth emulsion with a fatty film. “The oil from the chocolate becomes droplets in a continuous aqueous phase,” says Soltanahmadi. In other words, as solid cocoa particles and fat are released, the emulsion envelops the tongue and coats the palette, creating a smooth feeling of chocolate all over the mouth. That tactile sensation is part of the chocolate’s hedonistic appeal we crave, says Soltanahmadi.
Finding the sweet spot
After determining how chocolate is orally processed, the research team wanted to find the exact sweet spot of the breakdown of solid cocoa particles and fat as they are released into the mouth. They determined that the epicurean pleasure comes only from the chocolate's outer layer of fat; the secondary fatty layers inside the chocolate don’t add to the sensation. It was this final discovery that helped the team determine that it might be possible to produce healthier chocolate that would contain less oil, says Soltanahmadi. And therefore, less fat.
Rongjia Tao, a physicist at Temple University in Philadelphia, thinks the Leeds study and the concept behind it is “very interesting.” Tao, himself, did a study in 2016 and found he could reduce fat in milk chocolate by 20 percent. He believes that the Leeds researchers’ discovery about the first layer of fat being more important for taste than the other layer can inform future chocolate manufacturing. “As a scientist I consider this significant and an important starting point,” he says.
Chocolate is rich in polyphenols, naturally occurring compounds also found in fruits and vegetables, such as grapes, apples and berries. Research found that plant polyphenols can protect against cancer, diabetes and osteoporosis as well as cardiovascular ad neurodegenerative diseases.
Not everyone thinks it’s a good idea, such as chef Michael Antonorsi, founder and owner of Chuao Chocolatier, one of the leading chocolate makers in the U.S. First, he says, “cacao fat is definitely a good fat.” Second, he’s not thrilled that science is trying to interfere with nature. “Every time we've tried to intervene and change nature, we get things out of balance,” says Antonorsi. “There’s a reason cacao is botanically known as food of the gods. The botanical name is the Theobroma cacao: Theobroma in ancient Greek, Theo is God and Brahma is food. So it's a food of the gods,” Antonorsi explains. He’s doubtful that a chocolate made only with a top layer of fat will produce the same epicurean satisfaction. “You're not going to achieve the same sensation because that surface fat is going to dissipate and there is no fat from behind coming to take over,” he says.
Without layers of fat, Antonorsi fears the deeply satisfying experiential part of savoring chocolate will be lost. The University of Leeds team, however, thinks that it may be possible to make chocolate healthier - when consumed in limited amounts - without sacrificing its taste. They believe the concept of less fatty but no less slick chocolate will resonate with at least some chocolate-makers and consumers, too.
Chocolate already contains some healthful compounds. Its cocoa particles have “loads of health benefits,” says Soltanahmadi. Dark chocolate usually has more cocoa than milk chocolate. Some experts recommend that dark chocolate should contain at least 70 percent cocoa in order for it to offer some health benefit. Research has shown that the cocoa in chocolate is rich in polyphenols, naturally occurring compounds also found in fruits and vegetables, such as grapes, apples and berries. Research has shown that consuming plant polyphenols can be protective against cancer, diabetes and osteoporosis as well as cardiovascular and neurodegenerative diseases.
“So keeping the healthy part of it and reducing the oily part of it, which is not healthy, but is giving you that indulgence of it … that was the final aim,” Soltanahmadi says. He adds that the team has been approached by individuals in the chocolate industry about their research. “Everyone wants to have a healthy chocolate, which at the same time tastes brilliant and gives you that self-indulging experience.”
Probiotic bacteria can be engineered to fight antibiotic-resistant superbugs by releasing chemicals that kill them.
In recent years, researchers have been exploring a promising avenue: the use of synthetic biology to engineer new bacteria that may work better than antibiotics. The need continues to grow, as a Lancet study linked antibiotic resistance to over 1.27 million deaths worldwide in 2019, surpassing HIV/AIDS and malaria. The western sub-Saharan Africa region had the highest death rate (27.3 people per 100,000).
Researchers warn that if nothing changes, by 2050, antibiotic resistance could kill 10 million people annually.
To make it worse, our remedy pipelines are drying up. Out of the 18 biggest pharmaceutical companies, 15 abandoned antibiotic development by 2013. According to the AMR Action Fund, venture capital has remained indifferent towards biotech start-ups developing new antibiotics. In 2019, at least two antibiotic start-ups filed for bankruptcy. As of December 2020, there were 43 new antibiotics in clinical development. But because they are based on previously known molecules, scientists say they are inadequate for treating multidrug-resistant bacteria. Researchers warn that if nothing changes, by 2050, antibiotic resistance could kill 10 million people annually.
The rise of synthetic biology
To circumvent this dire future, scientists have been working on alternative solutions using synthetic biology tools, meaning genetically modifying good bacteria to fight the bad ones.
From the time life evolved on earth around 3.8 billion years ago, bacteria have engaged in biological warfare. They constantly strategize new methods to combat each other by synthesizing toxic proteins that kill competition.
For example, Escherichia coli produces bacteriocins or toxins to kill other strains of E.coli that attempt to colonize the same habitat. Microbes like E.coli (which are not all pathogenic) are also naturally present in the human microbiome. The human microbiome harbors up to 100 trillion symbiotic microbial cells. The majority of them are beneficial organisms residing in the gut at different compositions.
The chemicals that these “good bacteria” produce do not pose any health risks to us, but can be toxic to other bacteria, particularly to human pathogens. For the last three decades, scientists have been manipulating bacteria’s biological warfare tactics to our collective advantage.
In the late 1990s, researchers drew inspiration from electrical and computing engineering principles that involve constructing digital circuits to control devices. In certain ways, every cell in living organisms works like a tiny computer. The cell receives messages in the form of biochemical molecules that cling on to its surface. Those messages get processed within the cells through a series of complex molecular interactions.
Synthetic biologists can harness these living cells’ information processing skills and use them to construct genetic circuits that perform specific instructions—for example, secrete a toxin that kills pathogenic bacteria. “Any synthetic genetic circuit is merely a piece of information that hangs around in the bacteria’s cytoplasm,” explains José Rubén Morones-Ramírez, a professor at the Autonomous University of Nuevo León, Mexico. Then the ribosome, which synthesizes proteins in the cell, processes that new information, making the compounds scientists want bacteria to make. “The genetic circuit remains separated from the living cell’s DNA,” Morones-Ramírez explains. When the engineered bacteria replicates, the genetic circuit doesn’t become part of its genome.
Highly intelligent by bacterial standards, some multidrug resistant V. cholerae strains can also “collaborate” with other intestinal bacterial species to gain advantage and take hold of the gut.
In 2000, Boston-based researchers constructed an E.coli with a genetic switch that toggled between turning genes on and off two. Later, they built some safety checks into their bacteria. “To prevent unintentional or deleterious consequences, in 2009, we built a safety switch in the engineered bacteria’s genetic circuit that gets triggered after it gets exposed to a pathogen," says James Collins, a professor of biological engineering at MIT and faculty member at Harvard University’s Wyss Institute. “After getting rid of the pathogen, the engineered bacteria is designed to switch off and leave the patient's body.”
Overuse and misuse of antibiotics causes resistant strains to evolve
Adobe Stock
Seek and destroy
As the field of synthetic biology developed, scientists began using engineered bacteria to tackle superbugs. They first focused on Vibrio cholerae, which in the 19th and 20th century caused cholera pandemics in India, China, the Middle East, Europe, and Americas. Like many other bacteria, V. cholerae communicate with each other via quorum sensing, a process in which the microorganisms release different signaling molecules, to convey messages to its brethren. Highly intelligent by bacterial standards, some multidrug resistant V. cholerae strains can also “collaborate” with other intestinal bacterial species to gain advantage and take hold of the gut. When untreated, cholera has a mortality rate of 25 to 50 percent and outbreaks frequently occur in developing countries, especially during floods and droughts.
Sometimes, however, V. cholerae makes mistakes. In 2008, researchers at Cornell University observed that when quorum sensing V. cholerae accidentally released high concentrations of a signaling molecule called CAI-1, it had a counterproductive effect—the pathogen couldn’t colonize the gut.
So the group, led by John March, professor of biological and environmental engineering, developed a novel strategy to combat V. cholerae. They genetically engineered E.coli to eavesdrop on V. cholerae communication networks and equipped it with the ability to release the CAI-1 molecules. That interfered with V. cholerae progress. Two years later, the Cornell team showed that V. cholerae-infected mice treated with engineered E.coli had a 92 percent survival rate.
These findings inspired researchers to sic the good bacteria present in foods like yogurt and kimchi onto the drug-resistant ones.
Three years later in 2011, Singapore-based scientists engineered E.coli to detect and destroy Pseudomonas aeruginosa, an often drug-resistant pathogen that causes pneumonia, urinary tract infections, and sepsis. Once the genetically engineered E.coli found its target through its quorum sensing molecules, it then released a peptide, that could eradicate 99 percent of P. aeruginosa cells in a test-tube experiment. The team outlined their work in a Molecular Systems Biology study.
“At the time, we knew that we were entering new, uncharted territory,” says lead author Matthew Chang, an associate professor and synthetic biologist at the National University of Singapore and lead author of the study. “To date, we are still in the process of trying to understand how long these microbes stay in our bodies and how they might continue to evolve.”
More teams followed the same path. In a 2013 study, MIT researchers also genetically engineered E.coli to detect P. aeruginosa via the pathogen’s quorum-sensing molecules. It then destroyed the pathogen by secreting a lab-made toxin.
Probiotics that fight
A year later in 2014, a Nature study found that the abundance of Ruminococcus obeum, a probiotic bacteria naturally occurring in the human microbiome, interrupts and reduces V.cholerae’s colonization— by detecting the pathogen’s quorum sensing molecules. The natural accumulation of R. obeum in Bangladeshi adults helped them recover from cholera despite living in an area with frequent outbreaks.
The findings from 2008 to 2014 inspired Collins and his team to delve into how good bacteria present in foods like yogurt and kimchi can attack drug-resistant bacteria. In 2018, Collins and his team developed the engineered probiotic strategy. They tweaked a bacteria commonly found in yogurt called Lactococcus lactis to treat cholera.
Engineered bacteria can be trained to target pathogens when they are at their most vulnerable metabolic stage in the human gut. --José Rubén Morones-Ramírez.
More scientists followed with more experiments. So far, researchers have engineered various probiotic organisms to fight pathogenic bacteria like Staphylococcus aureus (leading cause of skin, tissue, bone, joint and blood infections) and Clostridium perfringens (which causes watery diarrhea) in test-tube and animal experiments. In 2020, Russian scientists engineered a probiotic called Pichia pastoris to produce an enzyme called lysostaphin that eradicated S. aureus in vitro. Another 2020 study from China used an engineered probiotic bacteria Lactobacilli casei as a vaccine to prevent C. perfringens infection in rabbits.
In a study last year, Ramírez’s group at the Autonomous University of Nuevo León, engineered E. coli to detect quorum-sensing molecules from Methicillin-resistant Staphylococcus aureus or MRSA, a notorious superbug. The E. coli then releases a bacteriocin that kills MRSA. “An antibiotic is just a molecule that is not intelligent,” says Ramírez. “On the other hand, engineered bacteria can be trained to target pathogens when they are at their most vulnerable metabolic stage in the human gut.”
Collins and Timothy Lu, an associate professor of biological engineering at MIT, found that engineered E. coli can help treat other conditions—such as phenylketonuria, a rare metabolic disorder, that causes the build-up of an amino acid phenylalanine. Their start-up Synlogic aims to commercialize the technology, and has completed a phase 2 clinical trial.
Circumventing the challenges
The bacteria-engineering technique is not without pitfalls. One major challenge is that beneficial gut bacteria produce their own quorum-sensing molecules that can be similar to those that pathogens secrete. If an engineered bacteria’s biosensor is not specific enough, it will be ineffective.
Another concern is whether engineered bacteria might mutate after entering the gut. “As with any technology, there are risks where bad actors could have the capability to engineer a microbe to act quite nastily,” says Collins of MIT. But Collins and Ramírez both insist that the chances of the engineered bacteria mutating on its own are virtually non-existent. “It is extremely unlikely for the engineered bacteria to mutate,” Ramírez says. “Coaxing a living cell to do anything on command is immensely challenging. Usually, the greater risk is that the engineered bacteria entirely lose its functionality.”
However, the biggest challenge is bringing the curative bacteria to consumers. Pharmaceutical companies aren’t interested in antibiotics or their alternatives because it’s less profitable than developing new medicines for non-infectious diseases. Unlike the more chronic conditions like diabetes or cancer that require long-term medications, infectious diseases are usually treated much quicker. Running clinical trials are expensive and antibiotic-alternatives aren’t lucrative enough.
“Unfortunately, new medications for antibiotic resistant infections have been pushed to the bottom of the field,” says Lu of MIT. “It's not because the technology does not work. This is more of a market issue. Because clinical trials cost hundreds of millions of dollars, the only solution is that governments will need to fund them.” Lu stresses that societies must lobby to change how the modern healthcare industry works. “The whole world needs better treatments for antibiotic resistance.”