Addiction Crisis

<p></p><p>Hear firsthand from individuals struggling with addiction and follow the cutting-edge work of doctors and scientists as they investigate why addiction is not a moral failing, but a chronic, treatable medical condition. Easy access to drugs like heroin, fentanyl, and even prescription medications like OxyContin has fueled an epidemic of addiction—the deadliest in U.S. history. Now, science is revealing how addiction affects the brain, and top experts are gathering evidence about how we should address our drug problem, from embracing evidence-based treatments, to rethinking public policies. (Premiered October 17, 2018)</p><p></p>

<p>Discover how opioid addiction affects the brain and how evidence-based treatments are saving lives.</p>

Addiction

swings-opioid-buffalo

<p>In Western New York, public health officials have organized a task force that’s giving people who suffer from opiate use disorder a new beginning.</p>

Restoring Hope: Fighting the Opioid Crisis in Buffalo

Could Cadaver Organs Save Your Life? Hero

<p>As the number of people who need organs goes up, the number of donors has plateaued, meaning we need to find new solutions. Dr. Doris Taylor and her team’s answer: custom-building organs from cadavers.</p>

<p>Custom-built lungs, livers, kidneys and hearts could someday save thousands of lives.</p>

Could Cadaver Organs Save Your Life?

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Body & Brain

Koch Foundation

Draper





  
      <div class="rich-text"><p>As an artist, he used science to understand the human body. As an anatomist, he used art to illuminate secrets beneath the flesh.</p><p>Five hundred years after Leonardo da Vinci’s death, his anatomical drawings are as powerful and poignant as they were in his time. Their beauty is breathtaking, their accuracy a testament to the genius of an artist willing to go to extremes to depict the human form.</p></div>
  

  
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      <div class="rich-text"><h3><b>Gifts to science</b></h3><p>About a dozen cadavers lie sealed in blue body bags on stainless steel tables in the anatomy lab at the Boston University School of Medicine. Trudy Van Houten unzips one of the bags to reveal the body of a tall, elderly man. Prepared with embalming fluids, the body is ready for dissection.</p><p>Van Houten, an assistant professor of anatomy and neurobiology at the school, has taught clinical anatomy for 30 years. She leans over the body, glasses perched on the edge of her nose.</p><p>Her young assistant passes her a scalpel. She makes a neat incision into the skin of the upper right arm. Minutes later, she uses forceps to lift the <a href="https://www.healthline.com/human-body-maps/biceps-brachii#1">biceps brachii muscle</a>, which extends between the shoulder and elbow. Next to her, a television monitor displays a magnified image of <a href="https://www.rct.uk/collection/919013/recto-the-muscles-of-the-shoulder-and-arm-verso-the-muscles-of-the-shoulder-and">one of da Vinci&#x27;s drawings</a> of a dissected arm. The muscles appear long and lithe, shaded in with lines that blend into a yellowed background.</p><p>The scene is being filmed for the NOVA documentary “<a href="https://www.pbs.org/wgbh/nova/video/decoding-da-vinci/">Decoding da Vinci</a>,” which probes the mysteries behind some of da Vinci’s most brilliant work. “His depictions of the human body were beautiful,” Van Houten later says. “And so accurate that we can actually use them to teach.”</p><p>Van Houten insists images are critical in teaching anatomy. “It’s something that anyone who teaches anatomy faces,” she says. “You can’t teach it without pictures.”</p><p>And although educators can now draw on 3D imagery and other computer-based models, Van Houten prefers the real thing. “The best models we have are dissected human bodies,” she says.</p>
            <figure class="richtext-image full-width"><img alt="Leonardo_da_Vinci_Story_Image.jpg" class="richtext-image full-width" height="478" width="800"
            src="/wgbh/nova/media/images/Leonardo_da_Vinci_Story_Image.width-800.jpg"/><figcaption><p>Anatomical studies of the shoulder. Image Credit: Wikimedia Commons, Leonardo da Vinci.</p><div class="credit"><p></p></div></figcaption>
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            <p>The bodies are donated to the school through its <a href="https://www.bumc.bu.edu/anatneuro/anatomical-gifts/">anatomical gift program</a><b>.</b></p><p>Hundreds of students dissect the bodies, working in groups of eight. “They dissect from skin to skeleton,” says the program’s director, Robert Bouchie. “We start with the back and limbs.”</p><p>After the dissections are done, Bouchie leads a <a href="https://www.youtube.com/watch?v=mvbfH5YoEwo">memorial ceremony</a> for each body, which is then cremated. He and the students place the body in a coffin. There is a moment of silence. Family of the deceased often attend, he says.</p><p>Bouchie returns cremains in person to a handful of families each year. He explains why. “You can’t send it UPS, you can’t send it FedEx,” he says. “You have to send it USPS.”</p><p>Bouchie recalls once being asked the value of packed cremains by a postal worker. He told her the package was priceless. “So the clerk said I had to declare a value of zero,” he says. “I wasn’t comfortable with that.”</p></div>
  

  
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      <div class="rich-text"><h3><b>Human dissection: A unique learning tool</b></h3><p>Before the advent of modern imaging, dissections revealed the complicated inner workings of the human body when there was, perhaps, no other way. Da Vinci yearned to witness these mechanics for himself. Though he lacked any formal medical training, he is believed to have dissected more than <a href="https://www.rct.uk/collection/themes/exhibitions/leonardo-da-vinci/the-queens-gallery-buckingham-palace/leonardo-and-dissection">30 bodies</a> in his lifetime.</p><p>Though human dissections date back to <a href="https://www.britannica.com/biography/Herophilus">about the third century BCE</a>, the first <a href="https://link.springer.com/article/10.1007/s11999-016-5213-5">recorded public dissection</a> took place around 1315, when Italian physician and anatomist Mondino de Luzzi performed a dissection on an <a href="https://books.google.com/books?id=GeCFKXHYYEEC&amp;pg=PA177&amp;lpg=PA177&amp;dq=Mondino+de%E2%80%99+Liuzzi,+dissection,+1315,+criminal&amp;source=bl&amp;ots=TjzcVTNm84&amp;sig=ACfU3U25gW3Yz86tGnsQsSvVky7kQ_mNpQ&amp;hl=en&amp;sa=X&amp;ved=2ahUKEwjnkLaWlanlAhWtVt8KHSBlCOoQ6AEwEHoECAoQAQ#v=onepage&amp;q=Mondino%20de%E2%80%99%20Liuzzi%2C%20dissection%2C%201315%2C%20criminal&amp;f=false">executed criminal</a>.</p><p>The seminal anatomical book collection “<a href="https://www.metmuseum.org/toah/works-of-art/53.682/">De Humani Corporis Fabrica</a><i>”</i> (On the Structure of the Human Body)<i>,</i> by Flemish anatomist and physician Andreas Vesalius, was published in 1543. The books dispelled anatomical theories that had been entrenched since the second century. Vesalius, however, also pillaged cemeteries <a href="https://www.joh.cam.ac.uk/library/andreas-vesalius-and-challenge-galen">in search of corpses</a> for dissection.</p><p>Grave-robbing became a serious problem in the 18th and 19th centuries in some parts of Europe as well as the United States, where African American graves were especially vulnerable. Iron coffins and cage-like structures, known as <a href="https://www.atlasobscura.com/places/greyfriars-cemetery-mortsafes">mortsafes</a>, were used to protect graves from body snatchers in England and Scotland. In a notorious case, <a href="https://www.youtube.com/watch?v=FyE3MyaLD-U">William Burke and William Hare</a> murdered at least 16 people in Edinburgh, selling their bodies for dissection.</p><p>The British Parliament passed the <a href="https://www.youtube.com/watch?v=SPdhgnN9DbA">Anatomy Act</a> in 1832, which made it legal for medical schools to dissect unclaimed bodies from workhouses and hospitals. The law curbed the practice of body snatching in Britain but disproportionately <a href="https://kingscollections.org/exhibitions/specialcollections/charles-dickens-2/italian-boy/anatomy-act">affected the poor</a>.</p><p>For centuries, laws in Europe and the United States allowed dissections of <a href="https://www.ncbi.nlm.nih.gov/books/NBK481735/">executed criminals</a>. However, da Vinci was able to procure bodies from hospitals across Italy. In Florence, he befriended a centenarian who he then witnessed peacefully pass away.</p><p>He later dissected the man’s body. The study led to da Vinci’s very early description of arteriosclerosis.</p>
            <figure class="richtext-image full-width"><img alt="VetruvianSquare.jpg" class="richtext-image full-width" height="753" width="753"
            src="/wgbh/nova/media/images/VetruvianSquare.width-800.jpg"/><figcaption><p>&quot;Vitruvian Man&quot; by Leonardo da Vinci. Image Credit: Wikimedia Commons, Leonardo da Vinci.</p><div class="credit"><p></p></div></figcaption>
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            <h3><b>Science meets art</b></h3><p>Da Vinci was not the only <a href="https://www.metmuseum.org/toah/hd/anat/hd_anat.htm">Renaissance artist</a> who performed human dissections. And his findings were <a href="https://www.theguardian.com/science/2012/may/13/leonardo-da-vinci-anatomy-drawings">not always correct</a>. Yet, his anatomical studies remain scientifically significant.</p><p>He correctly described the heart as the center of the blood system and was the first to describe it as a muscle with <a href="https://www.cdc.gov/ncbddd/heartdefects/howtheheartworks.html">four chambers</a>. He discovered how small vortices of blood help shut the aortic valve, but because his scientific papers and anatomical drawings went unpublished for centuries, this mechanism wasn’t <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2804084/">confirmed</a> until the late 1960s.</p><p>“He started with an interest of understanding the body to improve his art,” explains “Decoding da Vinci” producer Doug Hamilton. “But he clearly went further. He clearly became fascinated by understanding the human body<i>.”</i></p><p>Da Vinci often dissected <a href="https://fn.bmj.com/content/77/3/F249">by candlelight</a>, taking left-handed, <a href="https://www.mos.org/leonardo/activities/mirror-writing">mirrored notes</a> throughout the process. “There&#x27;s no refrigeration, he&#x27;s sometimes doing it in the dark of night,” says Hamilton. “It’s a messy, smelly business. And yet, when you look at his drawings they don&#x27;t convey any of that. They convey the beauty of the body.”</p><p>More than <a href="https://www.bl.uk/collection-items/leonardo-da-vinci-notebook">7,000 pages</a> of Da Vinci’s notes and drawings still survive. A painter, sculptor, architect, and engineer, da Vinci made visionary drawings of a giant crossbow, a simplistic machine gun, winged flying machines, and a self-propelled cart—which <a href="https://www.wired.com/brandlab/2016/03/a-brief-history-of-autonomous-vehicle-technology/">some say</a> is the first design of a <a href="https://www.pbs.org/wgbh/nova/video/look-whos-driving/?fbclid=IwAR3Vacc_vkYq6hwc-RA5CoIsJfu6A66fgpPKWMyM7d8U-Q2OcBKThQKU3OA">self-driving vehicle</a><b>.</b> He also designed canal locks, buildings, and bridges.</p><p>Then there were masterpieces like “Mona Lisa,” “The Last Supper,” and “<a href="https://news.harvard.edu/gazette/story/2017/11/author-walter-isaacson-profiles-the-ultimate-renaissance-man-leonardo-da-vinci/">Vitruvian Man</a>,” a drawing that perfectly illustrates the fusion of art and science in da Vinci’s work.</p><p>Leonardo didn’t draw distinctions between art and science the way we do today, Hamilton says. The documentary, he says, is “an extraordinary story of how his scientific understanding went beyond what he needed to know to paint.”</p><p><i>Tune in or stream “</i><a href="https://www.pbs.org/wgbh/nova/video/decoding-da-vinci/"><i>Decoding da Vinci</i></a><i>” on November 13 at 9/8c on PBS to learn more about the science behind Leonardo da Vinci’s art.</i></p></div>
  

  
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<p>Leonardo da Vinci dissected some 30 cadavers in his lifetime, leaving behind a trove of beautiful—and accurate—anatomical drawings.</p>

Anatomy professor uses 500-year-old da Vinci drawings to guide cadaver dissection

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<p>Is violence actually declining? If so, why? And can we build a more peaceful future?</p>
<p>Despite the constant news of violence, from mass shootings to wars, psychologist Steven Pinker believes we may be living in one of the most peaceful periods in human existence. Could it be true that physical violence has been in decline for centuries? And can it be prevented—or is it simply part of human nature? NOVA takes you on a journey through history and the human mind to explore what triggers violence and how it may have decreased over time. Taking clues from a Kenyan archaeology site, modern laboratory experiments, and even literature, researchers trace the social and neurobiological roots of human violence. They look at how individual forces, like income equality or personal contact through sports may curb violence in modern societies. And in places like Baltimore, where violence “interrupters” treat violence like a contagious disease, NOVA examines evidence-based approaches to making the world more peaceful. <b>(Premiering November 20, 2019 at 9 pm on PBS)</b></p>
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<p>Is violence actually declining? If so, why? And can we build a more peaceful future?</p>

The Violence Paradox





  
      <div class="rich-text"><p>If your anxious brain is keeping you up at night, <a href="https://www.researchgate.net/profile/Eti_Ben-Simon">Eti Ben Simon</a> has some not-so-great-news: The sleep you lose to stress might exact an additional emotional toll on your wellbeing the next day.</p><p>“Typically, people think of <a href="https://www.pbs.org/wgbh/nova/article/can-animals-survive-without-sleep/?utm_source=FBPAGE&amp;utm_medium=social&amp;utm_term=20190227&amp;utm_content=2152807857&amp;utm_campaign=NOVA+Next&amp;linkId=63940930">lost sleep</a> as a symptom of anxiety,” says the University of California, Berkeley neuroscientist. “But disturbed sleep can be an instigator of anxiety, too.”</p><p>Ben Simon and her colleagues have spent years studying the relationship between sleep deprivation and anxiety—two experiences that, from a neurobiological perspective, actually look pretty similar. The team’s <a href="https://www.nature.com/articles/s41562-019-0754-8">latest findings</a>, published today in the journal <i>Nature Human Behavior,</i> show that both affect brain regions that regulate emotions.</p></div>
  

  
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      <div class="rich-text"><p>Functionally, that means experiencing one can aggravate the other, fueling a cycle of stress and sleeplessness. It’s pretty much a two-way street, Ben Simon says. And it doesn’t take much to trip the system: Enduring even one session of low-quality shut-eye, the study suggests, can boost anxiety the next day.</p><p>But there’s a flip side to the findings, too. A good night’s sleep, Ben Simon says, could be a straightforward way to manage our emotions. With more research, she says, sleep therapy could someday offer an additional treatment option for those that struggle with chronic anxiety.</p><p>“This is a very elegant study,” says <a href="https://www.vanderbilt.edu/psychological_sciences/bio/bunmi-olatunji">Bunmi Olatunji</a>, an expert in anxiety disorders at Vanderbilt University who was not involved in the study. “They really went after the biological underpinnings of the relationship between sleep and anxiety, and that’s an important and unique contribution.”</p><p>Researchers have long been aware that low-quality sleep is intertwined with a number of mental health conditions. People with anxiety disorders frequently have <a href="https://adaa.org/understanding-anxiety/related-illnesses/sleep-disorders">trouble falling and staying asleep</a>, and insomnia can <a href="https://www.sleepfoundation.org/excessive-sleepiness/health-impact/complex-relationship-between-sleep-depression-anxiety">exacerbate the symptoms</a> of clinical anxiety. It’s an especially troubling connection, Ben Simon says, in a world where younger generations are <a href="http://sleepeducation.org/news/2019/07/18/college-students-are-not-getting-nearly-enough-sleep">staying up late</a> and feeling more <a href="https://gspp.berkeley.edu/centers/bifya/our-research-and-projects/mental-health-project/mental-health-project">stressed out</a> than ever.</p><p>But no one’s managed to compare the two experiences in a systematic way, she says, especially in the same individual. “We wanted to know if there was a shared neurobiological mechanism,” she explains.</p><p>To explore the link between the two conditions, Ben Simon and her colleagues recruited 18 healthy people for two overnight sessions: one where they were sent home for a normal night of rest, and another where they stayed at the lab and didn’t sleep at all. Before bedtime, the researchers scored the participants’ anxiety with a questionnaire. When they repeated the assessment the next morning, they found that a total lack of sleep triggered a 30% increase in anxiety levels.</p><p>To home in on the brain regions responsible for the uptick in stress, the researchers put the study subjects in a functional magnetic resonance imaging (fMRI) machine, which monitors blood flow as a proxy for brain activity, after each session. During the scan, participants watched a series of video clips, some of which featured distressing situations.</p><p>Compared to when they were well rested, sleep-deprived participants seemed to have trouble controlling their emotions when watching evocative scenes, Ben Simon says. In these people, emotive regions of the brain—like the amygdala and the dorsal anterior cingulate cortex—were quick to light up, while the prefrontal cortex, which can put the brakes on runaway feelings, stayed dim. Their brains, in other words, looked like they were experiencing anxiety in overdrive.</p></div>
  

  
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      <div class="rich-text"><p>“When you’re dealing with something emotional, you need to recruit the prefrontal cortex to help you regulate [your reaction],” Ben Simon says. It’s the region, she explains, that’s responsible for keeping us cool and collected in times of crisis. “You fail to do that when you’re sleep-deprived,” she says.</p><p>Sleep’s restorative powers are vast, Ben Simon says, and can equip the brain to cope with adversity. So-called deep sleep, a dreamless stage characterized by the <a href="https://www.pbs.org/wgbh/nova/article/zebrafish-sleep/">slow brain waves</a> it produces on an electroencephalogram (EEG), seems especially important for this process, she says. The more deep sleep participants got during their night of rest, the more active their prefrontal cortices were the day after—and the better managed their emotions.</p><p>“It’s a beautiful cycle,” Ben Simon says. “Being sleep deprived takes away your emotion regulation capabilities. And then sleep, specifically deep sleep, magically brings it back online, and lets you start your day calmer.”</p><p>Pulling an all-nighter is a drastic departure from a healthy snooze schedule. But that’s not the only way to deprive yourself of sleep, says <a href="https://www.binghamton.edu/psychology/people/profile.html?id=mcoles">Meredith Coles</a>, an expert in anxiety disorders at Binghamton University who wasn’t involved in the study.</p>
            <figure class="richtext-image full-width"><img alt="iStock-820818020.jpg" class="richtext-image full-width" height="534" width="800"
            src="/wgbh/nova/media/images/iStock-820818020.width-800.jpg"/><figcaption><p>Anxiety and sleep deprivation both affect the brain&#x27;s emotion processing centers, fueling a vicious cycle of stress and sleeplessness. Image Credit: amenic181, iStock</p><div class="credit"><p></p></div></figcaption>
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            <p>In a final experiment, Ben Simon and her team asked nearly 400 healthy people to fill out online surveys tracking their sleep quality and anxiety levels from the comfort of their own homes. Even minor disruptions to slumber, like frequent wake-ups, appeared to mess with people’s emotions: When they slept worse, they felt worse.</p><p>Historically, people have put “a lot of focus on the importance of sleep duration,” says <a href="https://case.fiu.edu/about/directory/profiles/mcmakin-dana.html">Dana McMakin</a>, a clinical psychologist who specializes in anxiety at Florida International University, but was not involved in the study. “But this makes it clear that sleep continuity and efficiency matter, too.”</p><p>Ben Simon hopes that sleep might someday play a role in the treatment of anxiety disorders. That has yet to be tested directly, as all the people studied in this particular paper were healthy individuals, McMakin points out. There are also probably more brain regions and pathways involved at the nexus of sleep and anxiety that have yet to be uncovered, Olatunji adds.</p><p>Still, the study hints at an exciting avenue for future research, he says, especially considering that many patients with anxiety disorders don’t respond to typical interventions.</p><p>Even for those hoping to ameliorate day-to-day stress, catching high-caliber z’s can be a powerful palliative, Coles says. After all, “there aren’t too many risks to just getting more sleep,” she says. “In my experience, the benefits to doing so...tend to come out even stronger than we predict.”</p></div>
  

  
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<p>From a neurobiology perspective, anxiety and sleep deprivation look very much alike.</p>

Poor-quality sleep could prime the brain for an anxious day





  
      <div class="rich-text"><p>One of the most important features of the human immune system is its incredible capacity for memory—the ability to remember a pathogen or other threat so that subsequent encounters take a lesser toll on wellbeing.</p><p>So it’s a pretty big problem when the body is forced to forget.</p><p>Reporting this week in the journals <a href="https://science.sciencemag.org/content/366/6465/599"><i>Science</i></a> and <a href="https://immunology.sciencemag.org/content/4/41/eaay6125"><i>Science Immunology</i></a><i>, </i>two teams of researchers have found that this is the modus operandi of measles virus. In addition to the disease brought on by the virus itself, measles can induce a kind of immune amnesia, leaving the body more vulnerable to infections it’s encountered before.</p><p>The findings underscore the urgent need for measles <a href="https://www.pbs.org/wgbh/nova/video/vaccinescalling-the-shots/">vaccination</a>, which could protect people from more than the virus the treatment directly targets, the researchers say. In recent years, however, <a href="https://www.pbs.org/wgbh/nova/article/autism-vaccine-myth/">anti-vaccination movements</a> have driven rates of vaccination down, prompting the number of measles cases to skyrocket on a global scale. More than 7 million cases and 100,000 deaths were reported in 2017, and numbers have continued to climb, Katrina Kretsinger of the World Health Organization, who was not involved in either study, <a href="https://www.newscientist.com/article/2222038-measles-has-a-devastating-and-long-term-effect-on-your-immune-system/">told Debora MacKenzie at <i>New Scientist</i></a>.</p></div>
  

  
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      <div class="rich-text"><p>“When parents say no to getting a measles vaccine, you’re not just taking a risk of your kid getting measles,” study author Michael J. Mina of Harvard Medical School <a href="https://www.nytimes.com/2019/10/31/health/measles-vaccine-immune-system.html">told Denise Grady at <i>The New York Times</i></a>. “You’re causing them to lose this amazing resource of defenses they’ve built up over the years before measles, and that puts them at risk of catching other infections.”</p><p>When certain immune cells encounter a pathogen, they’re able to scan its surface and memorize it, storing away identifying intel that will help mount a stronger, faster response if the invader visits again. Often key to this process are the immune cells that produce antibodies—potent molecules that can neutralize bacteria, viruses, and other threats.</p><p>In the first study, a team of scientists led by Steve Elledge of Harvard Medical School analyzed blood that had been taken from 77 unvaccinated children in the months before and after a measles outbreak that hit the Netherlands in 2013. After an encounter with measles, 11 to 73% of antibodies that kids had generated against a wide array of viruses and bacteria—including those that cause herpes and pneumonia—disappeared. </p><p>When the researchers tested another group of 32 children that had been vaccinated against measles, mumps, and rubella, they found their antibodies intact.</p><p>Rather than destroying the antibodies directly, measles virus seemed to be targeting the cells that churned them out. Accordingly, the biggest drops occurred in children with the most severe cases of measles, Elledge told Grady.</p><p>The results of the second study, which analyzed the immune cells of 26 of the same unvaccinated children in the Netherlands, built on these results. Measles, they found, was capable of picking off <i>several </i>types of immune cells—many of which mature over time as young bodies are repeatedly exposed to, and recover from, infection. The onslaught, the researchers wrote, essentially rewound the body’s clock, leaving immune systems in an immature state that looked as though it had been “reset back to infancy,” study author Colin Russell of the University of Amsterdam in the Netherlands told MacKenzie.</p><p>Though researchers have known for years that measles can <a href="https://www.pbs.org/wgbh/nova/article/measles-vaccine-protects-children-against-other-deadly-infections-too/">compromise the immune system</a>, the two new studies are the first to dive into how the virus exerts its effects, which are “pretty devastating,” Jennifer Lighter, a pediatric infectious disease physician and epidemiologist who was not involved in either study, <a href="https://www.washingtonpost.com/health/2019/10/31/measles-makes-your-body-forget-how-fight-other-diseases/">told Lena H. Sun at <i>The Washington Post</i></a>. </p></div>
  

  
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      <div class="rich-text"><p>It’s possible for the immune system to recover from a measles attack, the researchers explain. But the body would probably need to be reexposed to the infections it’s forgotten, either naturally or through vaccination, to rebuild the memory it lost—a process that could take five years, study author Velislava Petrova of the Wellcome Sanger Institute and Cambridge University <a href="https://www.theguardian.com/science/2019/oct/31/measles-wipes-out-immune-systems-memory-study-finds">told Hannah Devlin at <i>The Guardian</i></a>.</p><p>It’s an argument for measles vaccination (which is a package deal when children are given the common measles, mumps, and rubella, or MMR, vaccine), Lighter told Sun. Some members of the population, like those who are immune-compromised, aren’t medically eligible for vaccination—but being surrounded by vaccinated people can <a href="https://www.pbs.org/wgbh/nova/article/herd-immunity/">still protect them</a>.</p><p>Perhaps there’s a bit of irony to this: Our bodies must be taught to remember measles to avoid the risk of forgetting other pathogens. When first introduced in the 1960s, measles vaccinations prompted a plunge in infections—from measles, yes, but <a href="https://science.sciencemag.org/content/348/6235/694.full">several other pathogens</a> as well. Now it may finally be clear why: The vaccine, Lighter told Sun, “clearly has protection much greater than we previously recognized.”</p></div>
  

  
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<p>In addition to causing disease itself, the virus destroys immune cells trained to respond to other pathogens the body has encountered before.</p>

How measles virus triggers immune system ‘amnesia’





  
      <div class="rich-text"><p>Among great apes, we humans stick out—and our uber-impressive noggins deserve much of the credit. But sussing out the cognitive differences between the brains of people and other primates isn’t easy. To accomplish the task, researchers have done everything from mining the fossil record to shoring up the <a href="https://www.pbs.org/show/koko-gorilla-who-talks/">language learning skills of gorillas</a>.</p><p>Now, an international team of researchers has entered the fray with <a href="https://www.nature.com/articles/s41586-019-1654-9">an ambitious new technique</a>: watching human, chimpanzee, and macaque brains grow from scratch in a dish.</p></div>
  

  
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      <div class="rich-text"><p>Well, sort of. These lab-raised “brains” are technically organoids, three-dimensional clumps of cells that can self-organize and work together like a simple organ. Their <a href="https://www.nature.com/articles/s41586-019-1654-9">findings</a>, published today in the journal <i>Nature,</i> reaffirm that few structural differences exist between us and our cousins. But at the level of gene expression, the human organoids seemed to lag behind their great ape counterparts, taking longer to mature.</p><p>To grow the organoids, a team led by Gray Camp, a stem cell biologist at the Max Planck Institute for Evolutionary Anthropology in Germany, collected human, chimpanzee, and macaque cells and used a cocktail of chemicals to coax them into developing as neurons, or brain cells. Though done in a dish, the process is meant to mimic what happens in a developing embryo, with cells specializing and communicating with each other to become functional tissues.</p><p>The team’s method marks the first time researchers have been able to directly compare the developing organs of humans and great apes, Camp <a href="https://www.newscientist.com/article/2219657-humans-evolved-to-think-faster-by-slowing-down-brain-development/">told Clare Wilson at <i>New Scientist</i></a>.</p><p>For four months, the researchers monitored the cells, occasionally sampling their genetic material to track how the organoids were progressing along the typical developmental trajectory. Though the mini-brains looked mostly the same by eye, their gene expression patterns told a different story. At the same point in time, the chimpanzee and macaque neurons seemed more mature, while their human counterparts lagged behind in a way that was “striking,” Camp <a href="https://www.sciencenews.org/article/organoids-brains-human-chimpanzee-development">told Laura Sanders at <i>Science News</i></a>.</p></div>
  

  
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      <div class="rich-text"><p>It’s not totally clear why the delay exists or what effects it might have on cognitive ability. But the results do echo a pattern in human development: Even after we’re born, our brains <a href="https://www.nytimes.com/2016/12/21/science/youre-an-adult-your-brain-not-so-much.html">continue to change and mature</a>, settling down only after adolescence. Now, it seems it’s possible the process takes it sweet time from start to finish.</p><p>What’s observed in an organoid, however, won’t necessarily translate over to a full-blown brain, other researchers caution. The complexities of brain development in an actual fetus can’t be captured by a cluster of cells in a dish, Gül Dölen, a neuroscientist at Johns Hopkins University who was not involved in the study, <a href="https://gizmodo.com/scientists-use-lab-grown-brains-to-study-what-makes-us-1839099204">told Ryan F. Mandelbaum at <i>Gizmodo</i></a>.</p><p>“It’s still early days in the organoid world,” Paola Arlotta, a neurobiologist at Harvard University who wasn’t involved in the study, told Sanders. But, she adds the results still highlight “important differences” in the development of humans and their closest relatives on the tree of life. That, at least, is worth some thought.</p></div>
  

  
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<p>In a new study, brain-like organoids made from human cells were slower to mature than their chimpanzee and macaque counterparts.</p>

Lab-grown mini-brains highlight developmental differences between humans and great apes





  
      <div class="rich-text"><p>In June 2019, a team of scientists published a <a href="https://www.nature.com/articles/d41586-019-01739-w">study</a> that sent ripples throughout the scientific community. The mutation that Chinese scientist He Jiankui had <a href="https://www.pbs.org/wgbh/nova/article/crispr-gene-editing-live-births/">tried to engineer into embryos</a> last year, the authors argued, could shorten their lives.</p><p>Last week, the team retracted their <a href="https://www.ncbi.nlm.nih.gov/pubmed/31160814?dopt=Abstract">paper</a>, originally published in <i>Nature Medicine,</i> citing flaws in its design. <a href="https://www.biorxiv.org/content/10.1101/787986v2">Subsequent</a> <a href="https://www.biorxiv.org/content/10.1101/788117v1">efforts</a> by <a href="https://www.biorxiv.org/content/10.1101/784157v1">independent</a> research groups to repeat the study’s results also failed to find evidence that people carrying the mutation in question were more likely to die early.</p><p>Study author Rasmus Nielsen, a biologist at the University of California, Berkeley, first came forward about the paper’s validity on Twitter in September, <i>STAT News’</i> <a href="https://www.statnews.com/2019/09/27/major-error-undermines-study-suggesting-change-introduced-in-the-crispr-babies-experiment-shortens-lives/">Rebecca Robbins reported at the time</a>.</p><p>“The one thing that all scientists fear the most is to find out that a major result they have published was based on erroneous data,” Nielsen wrote.</p></div>
  

  
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      <div class="rich-text"><p>The original study was conducted in the wake of a series of controversial experiments by He Jiankui, who attempted to use the CRISPR gene-editing tool to manipulate a gene called CCR5 in twin girls born last year. A subset of the human population is born naturally carrying a version of CCR5 with a mutation called ∆32, which has been linked to resistance against certain strains of HIV. Though He’s strategy didn’t induce this exact mutation, it was intended to be comparable, and protect the infants—whose father is HIV positive—from succumbing to AIDS.</p><p>He was widely condemned by the scientific community, who criticized his work as, among other things, a serious and irresponsible breach of ethics—in part because the side effects of CRISPR editing and the mutation itself aren’t fully understood. The experiment also had mixed results: while He modified both copies of CCR5 in one of the twins, her sister carried edits in just one. And none of the changes were an exact match to naturally-occuring ∆32.</p><p>When published, Nielson’s study appeared to raise the stakes further. After sifting through genomes recorded in the UK Biobank database, Nielson and his team reported that carrying two copies of ∆32 was linked to earlier age of death.</p><p>In the months following, several groups (including Nielson’s) tried in vain to generate similar results with other genomic databases. With the help of David Reich, a geneticist at Harvard Medical School, Nielsen and his colleagues discovered a systematic error in the data they’d initially analyzed that had caused them to underestimate the number of people in the UK Biobank database with two copies of ∆32, <a href="https://www.nature.com/articles/d41586-019-03032-2">reports Ewen Callaway for <i>Nature News</i></a>. This mistake had given the researchers the false impression that double-∆32-ers were unexpectedly underrepresented in the population—something that’s often related to higher mortality.</p><p>Adjusting for that error essentially erases the effect the team initially observed. “If there is an effect on mortality, it is certainly not as strong as we previously reported,” Nielson told Robbins at <i>STAT</i>.</p></div>
  

  
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      <div class="rich-text"><p>That doesn’t mean ∆32 is entirely without its costs: Other studies have linked the variant with worse outcomes in <a href="https://www.ncbi.nlm.nih.gov/pubmed/25918237">flu</a> and <a href="https://www.nih.gov/news-events/news-releases/mutation-protects-against-hiv-infection-may-raise-risk-west-nile-virus-illness">West Nile virus</a> infections. On the flip side, CCR5 may still have valuable functions that haven’t yet been measured, Reich told Calloway, and seems “unwise” to edit out.</p><p>The retraction also doesn’t absolve He of his faulty scientific approach, which may still have yet untold repercussions. CRISPR remains a valuable tool for researchers worldwide, but it’s a tool that “needs to be used judiciously,” Dana Waring, education director and co-founder of pgEd, the Personal Genetics Education Project, <a href="https://www.pbs.org/wgbh/nova/article/crispr-gene-editing-live-births/">told <i>NOVA Next</i> last year</a>.</p><p>Importantly, the error doesn’t affect the rest of UK Biobank’s data, Nielson told Callaway. And it’s something the team should have caught the first time around, he said, adding, “We are very sorry for the confusion we might have spread by publishing these results.”</p></div>
  

  
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<p>The study, originally published in June, contained an error that its authors caught months later.</p>

Scientists retract study linking CRISPR baby mutation to early death

<p>Through a series of video clips, a viewing guide for the video clips, and a community screening guide for the documentary NOVA <i>Addiction</i>, the collection will help students better understand opioids and the disease of addiction.</p>

Topic: Body & Brain

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