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Ask a Chemist: How does handwashing kill coronavirus?
The physical action of handwashing plus the properties of soap is a one-two punch for the virus.
08 May, 2020
- A common recommendation from experts to help protect against coronavirus is to wash your hands often, but why? It turns out that each time you do it is an effective two-pronged attack.
- As Kate the Chemist explains, the virus has a weak outer membrane. By using the proper handwashing technique, you're actually breaking through that membrane and ripping the virus apart.
- Soap is an important part of the equation because of its two sides: the hydrophobic side (which grabs onto the virus), and the hydrophilic side (which grabs onto the water). Washing your hands with soap for at least 20 seconds allows the virus to be rinsed away.
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Kate the Chemist: Water is a freak substance. Here’s why.
Dr. Kate Biberdorf explains why boiling water makes it safer and how water molecules are unusual and cool.
01 May, 2020
- University of Texas professor and science entertainer Kate the Chemist joined Big Think to talk about water molecules and to answer two interesting and important questions: Why does boiling water make it safe to drink, and what happens to water when you boil or freeze it?
- According to Kate, when water is heated to a certain temperature (100°C/ 212°F) the hydrogen bonds break and it goes from a liquid to a gas state. Boiling for a minimum of 5 minutes kills any viruses and bacteria that were in the water.
- "Water is a freak and so it is one of my favorite molecules ever," Kate says. "It has these unique properties and we are surrounded by it constantly. We also are made of water. We have to drink water to survive...It's a really, really fun molecule to investigate."
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Why does coronavirus kill more men than women? Researchers may have found an important clue.
Men take longer to clear COVID-19 from their systems; a male-only coronavirus repository may be why.
23 April, 2020
(Photo: Dan Kitwood/Getty Images)
- A new study found that women clear coronavirus from their systems much faster than men.
- The researchers hypothesize that high concentrations of ACE2-expressing cells in the testes may store more coronavirus.
- There are many confounding factors to this mystery—some genetic, others social and behavioral.
<p>There's much we don't know about novel coronavirus. We don't know how the virus leaped from bats to humans—though <a href="https://www.sciencedaily.com/releases/2020/03/200326144342.htm" target="_blank">pangolins</a> seem the intermediate hosts. We don't know the <a href="https://www.statnews.com/2020/04/20/everything-we-know-about-coronavirus-immunity-and-antibodies-and-plenty-we-still-dont/" target="_blank">levels of antibodies</a> among recovering individuals or if <a href="https://news.harvard.edu/gazette/story/2020/04/covid-19-may-not-go-away-in-warmer-weather-as-do-colds/" target="_blank">warmer weather</a> will curb the virus's transmission rate.</p><p>One of the more perplexing COVID-19 mysteries is why the disease kills men at roughly twice the rate of women. As of this writing, New York City has suffered 146 COVID-19 deaths for every 100,000 men, according to the <a href="https://www1.nyc.gov/site/doh/covid/covid-19-data.page" target="_blank">city's Health Department data</a>. Conversely, 84 women have died in the city per 100,000. Men have also been hospitalized at a higher rate.</p><p>"More than two-thirds of the intubated patients are men," Dr. Joseph Lowy, a palliative care and hospice doctor at NYU Langone Health, told the <a href="https://www.nytimes.com/2020/04/07/health/coronavirus-new-york-men.html" target="_blank"><em>New York Times</em></a>. "I know of no other disease that has that type of predilection for one gender over another [excluding reproductive diseases]."</p><p>Data have shown <a href="https://www.cnn.com/2020/03/24/health/coronavirus-gender-mortality-intl/index.html" target="_blank">similar patterns</a> in China, Italy, <a href="https://academic.oup.com/cid/article/doi/10.1093/cid/ciaa354/5813861" target="_blank">South Korea</a>, and <a href="https://www.doh.wa.gov/Emergencies/Coronavirus" target="_blank">Washington state</a>.</p><p>But a recent study may have found an important clue in solving this mystery—a potential coronavirus repository found only in men. </p>
Where is coronavirus hiding?
<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yMzE1NTgxNy9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTY0ODY4NzkxMX0.D84W6ZUOhv6Q-Ki7ddiF3zmDLK_Z6vuXtzfB9R8zLAA/img.jpg?width=1245&coordinates=0%2C179%2C0%2C180&height=700" id="1cc38" class="rm-shortcode" data-rm-shortcode-id="b4e083fb45357e1fb56a8571e8cdc553" data-rm-shortcode-name="rebelmouse-image" />A laboratory technician at Queen Elizabeth University Hospital, Glasgow, holds a container of test-tube samples from people tested for novel coronavirus.
<p>The study, uploaded to <a href="https://www.medrxiv.org/content/10.1101/2020.04.16.20060566v1" target="_blank"><em>MedRxiv</em></a>, found that men take longer to clear the virus from their systems than women. Researchers at Montefiore Health System and Albert Einstein College of Medicine, in collaboration with Kasturba Hospital for Infectious Diseases, Mumbai, nasal swabbed patients to determine an active COVID-19 infection.</p><p>They then retested the individuals every day until the tests turned negative. The women took a median time of four days to clear the virus, while the men's median time was six days.</p><p>"COVID-19 studies worldwide have consistently shown a higher incidence and greater severity of the disease in men compared with <a href="https://medicalxpress.com/tags/women/" target="_blank">women</a>," Aditi Shastri, assistant professor of medicine at Einstein College and lead author of the study, said in the <a href="https://medicalxpress.com/news/2020-04-slower-clearance-coronavirus-infection-men.html" target="_blank">release</a>. "Our collaborative study found that men have more difficulty clearing <a href="https://medicalxpress.com/tags/coronavirus/" target="_blank">coronavirus</a> following infection, which could explain their more serious problems with COVID-19 disease."</p><p>For coronavirus to infect a cell, it must latch onto an angiotensin-converting enzyme II, or <a href="https://en.wikipedia.org/wiki/Angiotensin-converting_enzyme_2" target="_blank">ACE2</a>. These enzymes are attached to the cellular membranes of cells in organs such as the heart, lungs, kidneys, and intestines.</p><p>The researchers theorize that bodily areas with cells sporting high levels of ACE2 would be more susceptible to infection. After consulting three independent RNE expression databases, they found that ACE2 was highly expressed in testicular cells but had little expression in ovarian cells.</p><p>Taking men's slow viral clearance and the ACE2 expression of testicular cells together, they hypothesize that the testes may serve as a repository for the virus, explaining its extended occupancy in men.</p>Further research required
<div class="rm-shortcode" data-media_id="z9vH49bb" data-player_id="FvQKszTI" data-rm-shortcode-id="7ef1ab8ca2f90b28543d580c408ed25f"> <div id="botr_z9vH49bb_FvQKszTI_div" class="jwplayer-media" data-jwplayer-video-src="https://content.jwplatform.com/players/z9vH49bb-FvQKszTI.js"> <img src="https://cdn.jwplayer.com/thumbs/z9vH49bb-1920.jpg" class="jwplayer-media-preview" /> </div> <script src="https://content.jwplatform.com/players/z9vH49bb-FvQKszTI.js"></script> </div> <p>The Montefiore-Einstein study is currently preliminary, and further research will be required before researchers can determine what, if anything, its results illuminate.</p><p>The study is currently published on <em>Medrxiv</em>, a <a href="https://www.aje.com/arc/benefits-of-preprints-for-researchers/" target="_blank">preprint</a> distributor. This means the study has been shared publicly before undergoing the <a href="https://undsci.berkeley.edu/article/howscienceworks_16" target="_blank">peer-review process</a>.</p><p>Preprints allow researchers to communicate their findings before official publication, which can take months if not a year or longer. This pre-publication can lead to early feedback, increased visibility, and new collaborations. It's especially helpful for <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6400415/" target="_blank">early-career researchers</a> trying to establish themselves.</p><p>However, given the speed at which coronavirus is spreading, researchers have leaned on preprints as a means of disseminating data to other experts faster than the peer review allows. As a result, <em>Medrixiv</em> has seen a <a href="https://www.nytimes.com/2020/04/14/science/coronavirus-disinformation.html" target="_blank">surge of preprint studies</a>, but they must be read within the context of their preliminary status.</p><p>The Montefiore-Einstein also has its limitations. The study had an initial sample size of only 68 subjects (48 males, 20 females) and a further examination of three families. And the connection of coronavirus to ACE2 enzymes in the testes came from database research, not direct observation.</p><p>The researchers acknowledge the need for further investigation. In particular, Shastri stresses the need to confirm the coronavirus's ability to infect and multiply in testicular tissue. If other researchers find their data promising, they could move forward with new research to build upon the study and see if this clue fits into the mystery.</p>One clue among many
<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yMzE1NTc5NS9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTYyNTQ3NjEzMX0.G-p4KniVRhsHXoIOyFfzEARdN5nGXWWkkQa85x6_ooM/img.jpg?width=1245&coordinates=0%2C281%2C0%2C298&height=700" id="d50c6" class="rm-shortcode" data-rm-shortcode-id="938d51b21df264aae5e883e5f1f9c894" data-rm-shortcode-name="rebelmouse-image" />Coronavirus protesters in Los Angeles. Men are more likely than women to disregard health warnings from officials.
<p><a href="https://www.vox.com/2020/4/9/21215063/coronavirus-covid-19-deaths-men-women-sex-dying-why" target="_blank">Men's severe response to COVID-19</a> could be due to several factors, of which a viral repository is just one. Another could simply be the fact that men are, well, men.</p><p>"We see that even among individuals without known health issues and in children, males have worse outcomes," Ryan Steele, an assistant professor of clinical medicine in rheumatology, allergy, and immunology at Yale School of Medicine, told <a href="https://www.health.com/condition/infectious-diseases/coronavirus/why-coronavirus-kills-more-men-than-women" target="_blank"><em>Health</em></a>. "This would indicate that the underlying differences in the immune response among genders may play a larger role than we have appreciated so far."</p><p>Women have a far stronger immune system response, which researchers think may stem from their second X chromosome. Since the largest number of immune-related genes are X-linked, women may get a boost in immune expression—though, they are more at risk of <a href="https://www.sciencedirect.com/science/article/pii/S0896841111001259" target="_blank">autoimmune diseases</a>. Hormones may play a role, too. Estrogen has been shown to activate the cells involved in antiviral responses, while testosterone suppresses inflammation.</p><p>Scientists can't rule out behavioral factors either. In the United States, <a href="https://www.cdc.gov/tobacco/data_statistics/fact_sheets/adult_data/cig_smoking/index.htm" target="_blank">men are more likely to be smokers</a> than women and more likely to suffer from <a href="https://www.niaaa.nih.gov/publications/brochures-and-fact-sheets/alcohol-facts-and-statistics" target="_blank">alcohol use disorder</a>. Smokers are in the high-risk group for COVID-19, while <a href="https://bigthink.com/mind-brain/how-alcohol-affects-your-brain" target="_self">heavy alcohol use</a> has been shown to <a href="https://www.ncbi.nlm.nih.gov/pubmed/17922947" target="_blank">suppress a wide range of immune responses</a>.</p><p>Men have also been shown to delay seeking medical care, wash their hands less frequently, and be more <a href="https://www.reuters.com/article/us-health-coronavirus-gender-poll/u-s-men-less-likely-to-heed-health-warnings-as-coronavirus-death-toll-mounts-reuters-poll-idUSKBN21E1C9" target="_blank">disregarding of health warnings</a> about the coronavirus.</p><p>"There are profound sex differences in immune systems, and this pandemic is revealing them," Marcia Stefanick, professor of medicine at Stanford University School of Medicine, told <a href="https://www.wsj.com/articles/coronavirus-seems-to-be-infecting-and-killing-more-men-than-women-11585819801" target="_blank">the <em>Wall Street Journal</em></a>. "What is biology versus what are our social norms and gender behaviors confounds our ability to understand what's going on."</p><p>While we wait for researchers to separate the clues from the red herrings, men can do their part: Listen to the experts, seek care when necessary, and washing your hands.</p>
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Stanford scientists engineer a ‘smart toilet' that checks your health
The smart toilet can analyze urine and stool samples for disease markers and can even recognize an individual user's "analprint".
10 April, 2020
- The toilet has played an important role in the history of sanitation and health.
- Stanford scientists have developed a "smart toilet" technology that analyzes a person's urine and stool samples for disease markers.
- The toilet could assist health care professionals by collecting valuable data that is typically flushed down the drain.
<p>The toilet holds a special place in the history of health. For most of that history, people collected their waste in cesspits, chamber pots, or the occasional <a href="https://en.wikipedia.org/wiki/Pig_toilet" target="_blank">pigsty</a>, all precariously close to where they lived and what they ate. This meant our ancestors were never far from whipworm, cholera, typhoid, giardia, and the cavalcade of other pathogens that call feces home.</p><p><a href="https://www.discovermagazine.com/planet-earth/what-the-earliest-toilets-say-about-how-human-civilization-has-evolved" target="_blank">The earliest flushing toilets</a> only appeared around 4,000 years ago, courtesy of the Minoan and Indus Valley civilizations. And while much is made today of ancient <a href="https://www.theatlantic.com/health/archive/2016/01/ancient-roman-toilets-gross/423072/" target="_blank">Rome's plumbing prowess</a>, the Romans were no strangers to the micro-nasties mentioned above. May have had something to do with the sponge on a stick used for wiping in public latrines—which, yes, was also for public use.</p><p>By the mid-18<sup>th</sup> century, inventors began crafting the mechanisms that would make <a href="https://www.history.com/news/who-invented-the-flush-toilet" target="_blank">the modern toilet</a> possible. After that, a businessman named Thomas Crapper—his real name, though he is not the namesake of the <a href="https://www.etymonline.com/search?q=crapper" target="_blank">euphemism</a>—promoted and popularized the indoor water closet.</p><p>Since then, most of the advances in toilet technology have occurred downstream, erm, flush. Granted, the <a href="https://www.youtube.com/watch?v=s0tCO4NdKeU" target="_blank">Japanese have stepped up the toilet game</a>, incorporating heated seats, app functionality, and Bach string quartets into the experience. But these are chic accouterments to an otherwise set porcelain blueprint. </p><p>That changed with a new study out of Stanford.</p>
Going to see a doctor about a horse
<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yMjkyNjgyNS9vcmlnaW4ucG5nIiwiZXhwaXJlc19hdCI6MTY1MTIyNjIzNn0.6su7Ou7t5rgb2lN8NNb-DiocNrJPXEK_den4l3XFO-4/img.png?width=1245&coordinates=0%2C0%2C0%2C1&height=700" id="67d14" class="rm-shortcode" data-rm-shortcode-id="252269ad9326148a3fa1733dbd3487ba" data-rm-shortcode-name="rebelmouse-image" />An image and diagram showing where the smart toilet's pressure sensor and stool camera are located.
<p>Stanford researchers have completed a pilot study of their new "smart toilet" technology. The technology monitors user health through a suite of gadgets that evaluate urine and stool, well, samples. </p><p>The researchers <a href="https://www.nature.com/articles/s41551-020-0534-9" target="_blank">published their findings</a> in <em>Nature Biomedical Engineering</em> earlier this month.</p><p>"Our concept dates back well over 15 years," Sanjiv Gambhir, professor of radiology at Stanford and the study's senior author, said in <a href="http://med.stanford.edu/news/all-news/2020/04/smart-toilet-monitors-for-signs-of-disease.html" target="_blank">a release</a>. "When I'd bring it up, people would sort of laugh because it seemed like an interesting idea, but also a bit odd."</p><p>In truth, the researchers haven't designed a new toilet. They've outfitted a classic porcelain seat with an assortment of automated sensors and cameras to record the powder room happenings.</p><p>"It's sort of like buying a bidet add-on that can be mounted right into your existing toilet," Gambhir said. "And like a bidet, it has little extensions that can carry out different purposes."</p><p>The smart toilet uses pressure and motion sensors to track the frequency and duration of a user's restroom visits. A set of cameras then capture the deposits on video, while algorithms process the imagery to distinguish between healthy bowel movements and those showing signs of disease. </p><p>Urine is analyzed through <a href="https://www.urologyhealth.org/urologic-conditions/urodynamics" target="_blank">urodynamics</a>, which looks at the flow, rate, and magnitude of the stream. The stool is analyzed with the <a href="https://en.wikipedia.org/wiki/Bristol_stool_scale" target="_blank">Bristol stool scale</a>, which reviews consistency.</p><p>The toilet is also equipped with a urinalysis stick. This "dipstick test" can analyze urine for acidity, protein levels, white blood cell count, blood contamination, and other biomarkers.</p><p>The algorithms then compile the data for a preliminary diagnosis and send them directly to a health care provider's record-keeping system. These data could recognize the early signs for a host of diseases, such as kidney failure, irritable bowel syndrome, and colorectal cancer, much sooner than with traditional doctor visits.</p><p>And a major advantage to such a biometric device, Gambhir points out, is that it can't be duped by human interference or lack of commitment. Because everyone poops, it provides continuous health monitoring.<br></p><p>"The thing about a smart toilet, though, is that unlike wearables, you can't take it off," he said. "Everyone uses the bathroom—there's really no avoiding it—and that enhances its value as a disease-detecting device."</p>Yes, but does it have butt-recognition technology?
<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yMjkyNjgzOC9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTYxOTkxMDc2Nn0.M11ETl3hcr-RLYmdMuIeCbUV624HI-EzX-xmtiscxSE/img.jpg?width=1245&coordinates=0%2C155%2C0%2C153&height=700" id="d5103" class="rm-shortcode" data-rm-shortcode-id="f794c4dc7499f54c829ea0c5b159e828" data-rm-shortcode-name="rebelmouse-image" />A mascot for the 2014 "Toilet!? Human Waste and Earth's Future" exhibition in Tokyo.
<p>Obviously! There wouldn't be much point otherwise. </p><p>Since a house toilet will be used by a variety of people, Gambhir and his team had to devise a way for the technology to keep medical profiles distinct. They first added a fingerprint scanner to the flushing lever, and while it remains in the final design, they soon realized it wasn't enough. After all, if someone forgets to flush and another person flushes for them? Or the toilet has an automatic flush? That's valuable data down the drain.</p><p>So Gambhir and his team did the logical thing: They added a camera to the smart toilet that scans a user's anus to ensure health data is matched to the proper derriere.</p><p>Turns out a person's anal creases are as unique to them as the whorls on their fingerprints. That's because the pattern and number of creases are genetically determined, meaning only identical twins will have the same "analprint."<span></span></p><p>To assuage privacy concerns, the team secures all data transmission with end-to-end encryption that is HIPAA-compliant. Another approach is to use an infrared camera or low-intensity laser scanner, which allows the algorithm to produce an ID but does not produce a conventional image.</p><p>Interestingly, the idea of identifying people based on their analprint was not original to the team. According to <a href="https://bioengineeringcommunity.nature.com/users/384037-seung-min-park/posts/65145-precision-health-toilet-an-upgraded-smart-toilet" target="_blank">study author Seung-min Park</a>, the idea was borrowed from painter Salvador Dali, who studied anal creases for his <a href="http://www.all-art.org/art_20th_century/dali-6-7.html" target="_blank">unconventional erotic art</a>.</p>Waste not
<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yMjkyNjgzNi9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTYxMDAxMDczNn0.3pdaNrsYcNtYyLJEXNVZdrUSCASEQOVr0WQO-Kx8GO4/img.jpg?width=1245&coordinates=0%2C22%2C0%2C23&height=700" id="59886" class="rm-shortcode" data-rm-shortcode-id="32d95cdea4606175bf4589a0ef489b6b" data-rm-shortcode-name="rebelmouse-image" />We've come a long way since the hydraulic sewage system of the ancient Indus Valley civilizations.
<p>All told, 21 participants used the smart toilet during the pilot run. For the next study, Gambhir and his team are hoping to increase number of participants, add new stool analysis features, and improve existing ones.</p><p>"The smart toilet is the perfect way to harness a source of data that's typically ignored – and the user doesn't have to do anything differently," Gambhir said.</p>
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The growth of an organism rides on a pattern of waves
Study shows ripples across a newly fertilized egg are similar to ocean and atmospheric circulations.
25 March, 2020
Getty Images / Handout
When an egg cell of almost any sexually reproducing species is fertilized, it sets off a series of waves that ripple across the egg's surface.
<p> These waves are produced by billions of activated proteins that surge through the egg's membrane like streams of tiny burrowing sentinels, signaling the egg to start dividing, folding, and dividing again, to form the first cellular seeds of an organism.</p><p>Now MIT scientists have taken a detailed look at the pattern of these waves, produced on the surface of starfish eggs. These eggs are large and therefore easy to observe, and scientists consider starfish eggs to be representative of the eggs of many other animal species.</p><p>In each egg, the team introduced a protein to mimic the onset of fertilization, and recorded the pattern of waves that rippled across their surfaces in response. They observed that each wave emerged in a spiral pattern, and that multiple spirals whirled across an egg's surface at a time. Some spirals spontaneously appeared and swirled away in opposite directions, while others collided head-on and immediately disappeared.</p>
<p>The behavior of these swirling waves, the researchers realized, is similar to the waves generated in other, seemingly unrelated systems, such as the vortices in quantum fluids, the circulations in the atmosphere and oceans, and the electrical signals that propagate through the heart and brain.</p><p>"Not much was known about the dynamics of these surface waves in eggs, and after we started analyzing and modeling these waves, we found these same patterns show up in all these other systems," says physicist Nikta Fakhri, the Thomas D. and Virginia W. Cabot Assistant Professor at MIT. "It's a manifestation of this very universal wave pattern."</p><p>"It opens a completely new perspective," adds Jörn Dunkel, associate professor of mathematics at MIT. "You can borrow a lot of techniques people have developed to study similar patterns in other systems, to learn something about biology."</p><p>Fakhri and Dunkel have published their results today in the journal <em>Nature Physics.</em> Their co-authors are Tzer Han Tan, Jinghui Liu, Pearson Miller, and Melis Tekant of MIT.</p>
<h3>Finding one's center</h3><p>Previous studies have shown that the fertilization of an egg immediately activates Rho-GTP, a protein within the egg which normally floats around in the cell's cytoplasm in an inactive state. Once activated, billions of the protein rise up out of the cytoplasm's morass to attach to the egg's membrane, snaking along the wall in waves.</p><p>"Imagine if you have a very dirty aquarium, and once a fish swims close to the glass, you can see it," Dunkel explains. "In a similar way, the proteins are somewhere inside the cell, and when they become activated, they attach to the membrane, and you start to see them move."</p><p>Fakhri says the waves of proteins moving across the egg's membrane serve, in part, to organize cell division around the cell's core.</p><p>"The egg is a huge cell, and these proteins have to work together to find its center, so that the cell knows where to divide and fold, many times over, to form an organism," Fakhri says. "Without these proteins making waves, there would be no cell division."</p><p><img alt="" src="http://news.mit.edu/sites/mit.edu.newsoffice/files/images/egg-waves-2_0.gif"></p><p><em>MIT researchers observe ripples across a newly fertilized egg that are similar to other systems, from ocean and atmospheric circulations to quantum fluids. Courtesy of the researchers.</em></p><p>In their study, the team focused on the active form of Rho-GTP and the pattern of waves produced on an egg's surface when they altered the protein's concentration.</p><p>For their experiments, they obtained about 10 eggs from the ovaries of starfish through a minimally invasive surgical procedure. They introduced a hormone to stimulate maturation, and also injected fluorescent markers to attach to any active forms of Rho-GTP that rose up in response. They then observed each egg through a confocal microscope and watched as billions of the proteins activated and rippled across the egg's surface in response to varying concentrations of the artificial hormonal protein.</p><p>"In this way, we created a kaleidoscope of different patterns and looked at their resulting dynamics," Fakhri says.</p>
<h3>Hurricane track</h3><p>The researchers first assembled black-and-white videos of each egg, showing the bright waves that traveled over its surface. The brighter a region in a wave, the higher the concentration of Rho-GTP in that particular region. For each video, they compared the brightness, or concentration of protein from pixel to pixel, and used these comparisons to generate an animation of the same wave patterns.</p><p>From their videos, the team observed that waves seemed to oscillate outward as tiny, hurricane-like spirals. The researchers traced the origin of each wave to the core of each spiral, which they refer to as a "topological defect." Out of curiosity, they tracked the movement of these defects themselves. They did some statistical analysis to determine how fast certain defects moved across an egg's surface, and how often, and in what configurations the spirals popped up, collided, and disappeared.</p>
<p>In a surprising twist, they found that their statistical results, and the behavior of waves in an egg's surface, were the same as the behavior of waves in other larger and seemingly unrelated systems.</p><p>"When you look at the statistics of these defects, it's essentially the same as vortices in a fluid, or waves in the brain, or systems on a larger scale," Dunkel says. "It's the same universal phenomenon, just scaled down to the level of a cell."</p><p>The researchers are particularly interested in the waves' similarity to ideas in quantum computing. Just as the pattern of waves in an egg convey specific signals, in this case of cell division, quantum computing is a field that aims to manipulate atoms in a fluid, in precise patterns, in order to translate information and perform calculations.</p><p>"Perhaps now we can borrow ideas from quantum fluids, to build minicomputers from biological cells," Fakhri says. "We expect some differences, but we will try to explore [biological signaling waves] further as a tool for computation."</p><p>This research was supported, in part, by the James S. McDonnell Foundation, the Alfred P. Sloan Foundation, and the National Science Foundation.</p><p>Reprinted with permission of <a href="http://news.mit.edu/" target="_blank">MIT News</a>. Read the <a href="http://news.mit.edu/2020/growth-organism-waves-0323" target="_blank">original article</a>.</p>
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