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The appendix may have a purpose after all—and it's not good news
Is the appendix a useless organ, an immune system benefactor, a Parkinson's disease instigator, or all of the above?
- As far back as Darwin, scientists have thought the appendix was a vestigial organ, but opinions have changed in recent years.
- A new study found that the appendix houses Lewy bodies, abnormal protein deposits that contribute to Parkinson's disease.
- Researchers suggest an appendectomy may lower one's risk of Parkinson's, while other research suggests the appendix has important roles to play in our immune system.
If the appendix has a jam, it's definitely the Clash's Should I Stay or Should I Go. The organ always tease, tease, teases us with the possibility of appendicitis, an inflammation that is potentially life threatening if left alone. This said, since the appendix has long been touted to serve no known function, surgeons will even remove it as part of near any routine surgery. "While I'm in there, amiright?"
But that view has changed in recent years. New discoveries have led medical professionals to reassess the role of the appendix. Some experts believe it has an important role to play in our immune system, while others suggest a more sinister role.
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The appendix is a pinky-sized organ located at the junction of the large and small intestine. Image source: Shutterstock
For years, the medical profession believed the appendix was a vestigial organ — that is, it served a functional purpose in our evolutionary ancestors but has since lost that role. Goosebumps, for example, made our ancestors look larger and more intimidating, but they serve no function in the era of the full-body wax.
Similarly, scientists have posited that the appendix aided digestion in our leaf-noshing ancestors. Charles Darwin hypothesized humans once possessed a large cecum that stored special gut bacteria used to break down fibrous plant tissue. As our ancestors moved toward more easily digestible foods, such as fruit, our cecum began to shrink. The appendix, he wagered, was part of the cecum that shriveled to uselessness.
Today, the appendix loafs about in our abdomens, freeloading at the junction of your large and small intestines, where we pay little attention to it unless it becomes inflamed due to blockage or infection. Seeing as the appendix plays no known role, the response to such inflammation is simply to remove it, a procedure called an appendectomy.
A new study, however, suggests that appendectomies may pay dividends beyond curing appendicitis.
Whose side is the appendix on?
Published this fall in Science Translational Medicine, the study compared the health records of nearly 1.7 million Swedes over 52 years. It found that Swedes who underwent an appendectomy decreased their chance of developing Parkinson's disease by roughly 20 percent compared to the general population. A removed appendix also appeared to delay the onset of Parkinson's.
The culprit is not the appendix, per se, but the Lewy bodies it houses. Lewy bodies are abnormal deposits of alpha-synuclein proteins. When these proteins accumulate in neurons, they affect the brain's biochemical processes, leading to neurodegenerative diseases such as Parkinson's disease and Lewy body dementia. Scientists aren't sure how Lewy bodies alter the brain, but they do know these protein clumps appear in the gut before disease onset.
When the researchers analyzed appendix tissue from people who underwent an appendectomy, but were not diagnosed with Parkinson's, they found the tissue "contained high levels of intraneuronal alpha-synuclein aggregates" and was rich in truncated forms of the protein. This discovery strengthens the case that these protein clumps travel from the gut to the brain.
As neuroscientists Viviane Labrie told Science News, "[P]reventing excessive alpha-synuclein clump formation in the appendix, and its departure from the gastrointestinal tract, could be a useful new form of therapy."
Interestingly, the study found that an appendectomy showed the greatest benefits for Swedes living in rural areas. Rural living is associated with a higher risk early onset Parkinson's, but the research suggests that an appendectomy decreased the risk of Parkinson's for countryfolk by about 25 percent compared to the general population.
Appendix function: uncertain
An inflamed appendix being removed during an appendectomy. Image source: Wikimedia Commons
But let's not rush into your doctor's office and demand she remove your appendix. Not just yet.
While the study is eye opening, it does have some limitations. First, the study only looked at the appendix, so the authors are not sure what other gastrointestinal tissues may contain alpha-synuclein and what role that may play. Additionally, undetermined genetic and environmental factors may play significant roles, too.
And the appendix may yet be shown to provide salubrious benefits, as well. One study out of Midwestern University "discovered that the appendix has evolved independently in several mammal lineages, over 30 separate times, and almost never disappears from a lineage once it has appeared." The researchers believe this is strong evidence for an adaptive purpose.
Going back to Darwin, that adaptive purpose may be to safe house gut bacteria. A study published in the Journal of Theoretical Biology argues that immune system cells in the appendix protects good bacteria during trying abdominal circumstances.
For example, a gut can't differentiate between good and bad bacteria when it purges the system with a bout of diarrhea. During this time, the appendix houses good bacteria like an intestinal Noah's Ark. Once the inner, ahem, flooding has subsided, the good bacteria go forth to repopulate the gut.
Even if this theory is correct, people still live long and fruitful lives without an appendix, so the question that needs further research is whether the benefits of keeping your appendix outweigh the risks of keeping it.
Should the appendix stay or should it go? The answer, according to science, seems to be that if it goes there could be trouble, but if it stays, it may be double.
Innovation in manufacturing has crawled since the 1950s. That's about to speed up.
Health officials in China reported that a man was infected with bubonic plague, the infectious disease that caused the Black Death.
- The case was reported in the city of Bayannur, which has issued a level-three plague prevention warning.
- Modern antibiotics can effectively treat bubonic plague, which spreads mainly by fleas.
- Chinese health officials are also monitoring a newly discovered type of swine flu that has the potential to develop into a pandemic virus.
Bacteria under microscope
needpix.com<p>Today, bubonic plague can be treated effectively with antibiotics.</p><p style="margin-left: 20px;">"Unlike in the 14th century, we now have an understanding of how this disease is transmitted," Dr. Shanthi Kappagoda, an infectious disease physician at Stanford Health Care, told <a href="https://www.healthline.com/health-news/seriously-dont-worry-about-the-plague#Heres-how-the-plague-spreads" target="_blank">Healthline</a>. "We know how to prevent it — avoid handling sick or dead animals in areas where there is transmission. We are also able to treat patients who are infected with effective antibiotics, and can give antibiotics to people who may have been exposed to the bacteria [and] prevent them [from] getting sick."</p>
This plague patient is displaying a swollen, ruptured inguinal lymph node, or buboe.
Centers for Disease Control and Prevention<p>Still, hundreds of people develop bubonic plague every year. In the U.S., a handful of cases occur annually, particularly in New Mexico, Arizona and Colorado, <a href="https://www.cdc.gov/plague/faq/index.html" target="_blank">where habitats allow the bacteria to spread more easily among wild rodent populations</a>. But these cases are very rare, mainly because you need to be in close contact with rodents in order to get infected. And though plague can spread from human to human, this <a href="https://www.healthline.com/health-news/seriously-dont-worry-about-the-plague#Heres-how-the-plague-spreads" target="_blank">only occurs with pneumonic plague</a>, and transmission is also rare.</p>
A new swine flu in China<p>Last week, researchers in China also reported another public health concern: a new virus that has "all the essential hallmarks" of a pandemic virus.<br></p><p>In a paper published in the <a href="https://www.pnas.org/content/early/2020/06/23/1921186117" target="_blank">Proceedings of the National Academy of Sciences</a>, researchers say the virus was discovered in pigs in China, and it descended from the H1N1 virus, commonly called "swine flu." That virus was able to transmit from human to human, and it killed an estimated 151,700 to 575,400 people worldwide from 2009 to 2010, according to the Centers for Disease Control and Prevention.</p>There's no evidence showing that the new virus can spread from person to person. But the researchers did find that 10 percent of swine workers had been infected by the virus, called G4 reassortant EA H1N1. This level of infectivity raises concerns, because it "greatly enhances the opportunity for virus adaptation in humans and raises concerns for the possible generation of pandemic viruses," the researchers wrote.
So far, 30 student teams have entered the Indy Autonomous Challenge, scheduled for October 2021.
- The Indy Autonomous Challenge will task student teams with developing self-driving software for race cars.
- The competition requires cars to complete 20 laps within 25 minutes, meaning cars would need to average about 110 mph.
- The organizers say they hope to advance the field of driverless cars and "inspire the next generation of STEM talent."
Indy Autonomous Challenge<p>Completing the race in 25 minutes means the cars will need to average about 110 miles per hour. So, while the race may end up being a bit slower than a typical Indy 500 competition, in which winners average speeds of over 160 mph, it's still set to be the fastest autonomous race featuring full-size cars.</p><p style="margin-left: 20px;">"There is no human redundancy there," Matt Peak, managing director for Energy Systems Network, a nonprofit that develops technology for the automation and energy sectors, told the <a href="https://www.post-gazette.com/business/tech-news/2020/06/01/Indy-Autonomous-Challenge-Indy-500-Indianapolis-Motor-Speedway-Ansys-Aptiv-self-driving-cars/stories/202005280137" target="_blank">Pittsburgh Post-Gazette</a>. "Either your car makes this happen or smash into the wall you go."</p>
Illustration of the Indy Autonomous Challenge
Indy Autonomous Challenge<p>The Indy Autonomous Challenge <a href="https://www.indyautonomouschallenge.com/rules" target="_blank">describes</a> itself as a "past-the-post" competition, which "refers to a binary, objective, measurable performance rather than a subjective evaluation, judgement, or recognition."</p><p>This competition design was inspired by the 2004 DARPA Grand Challenge, which tasked teams with developing driverless cars and sending them along a 150-mile route in Southern California for a chance to win $1 million. But that prize went unclaimed, because within a few hours after starting, all the vehicles had suffered some kind of critical failure.</p>
Indianapolis Motor Speedway
Indy Autonomous Challenge<p>One factor that could prevent a similar outcome in the upcoming race is the ability to test-run cars on a virtual racetrack. The simulation software company Ansys Inc. has already developed a model of the Indianapolis Motor Speedway on which teams will test their algorithms as part of a series of qualifying rounds.</p><p style="margin-left: 20px;">"We can create, with physics, multiple real-life scenarios that are reflective of the real world," Ansys President Ajei Gopal told <a href="https://www.wsj.com/articles/autonomous-vehicles-to-race-at-indianapolis-motor-speedway-11595237401?mod=e2tw" target="_blank">The Wall Street Journal</a>. "We can use that to train the AI, so it starts to come up to speed."</p><p>Still, the race could reveal that self-driving cars aren't quite ready to race at speeds of over 110 mph. After all, regular self-driving cars already face enough logistical and technical roadblocks, including <a href="https://www.bbc.com/news/technology-53349313#:~:text=Tesla%20will%20be%20able%20to,no%20driver%20input%2C%20he%20said." target="_blank">crumbling infrastructure, communication issues</a> and the <a href="https://bigthink.com/paul-ratner/would-you-ride-in-a-car-thats-programmed-to-kill-you" target="_self">fateful moral decisions driverless cars will have to make in split seconds</a>.</p>But the Indy Autonomous Challenge <a href="https://static1.squarespace.com/static/5da73021d0636f4ec706fa0a/t/5dc0680c41954d4ef41ec2b2/1572890638793/Indy+Autonomous+Challenge+Ruleset+-+v5NOV2019+%282%29.pdf" target="_blank">says</a> its main goal is to advance the industry, by challenging "students around the world to imagine, invent, and prove a new generation of automated vehicle (AV) software and inspire the next generation of STEM talent."
A new Harvard study finds that the language you use affects patient outcome.
- A study at Harvard's McLean Hospital claims that using the language of chemical imbalances worsens patient outcomes.
- Though psychiatry has largely abandoned DSM categories, professor Joseph E Davis writes that the field continues to strive for a "brain-based diagnostic system."
- Chemical explanations of mental health appear to benefit pharmaceutical companies far more than patients.
Challenging the Chemical Imbalance Theory of Mental Disorders: Robert Whitaker, Journalist<span style="display:block;position:relative;padding-top:56.25%;" class="rm-shortcode" data-rm-shortcode-id="41699c8c2cb2aee9271a36646e0bee7d"><iframe type="lazy-iframe" data-runner-src="https://www.youtube.com/embed/-8BDC7i8Yyw?rel=0" width="100%" height="auto" frameborder="0" scrolling="no" style="position:absolute;top:0;left:0;width:100%;height:100%;"></iframe></span><p>This is a far cry from Howard Rusk's 1947 NY Times editorial calling for mental healt</p><p>h disorders to be treated similarly to physical disease (such as diabetes and cancer). This mindset—not attributable to Rusk alone; he was merely relaying the psychiatric currency of the time—has dominated the field for decades: mental anguish is a genetic and/or chemical-deficiency disorder that must be treated pharmacologically.</p><p>Even as psychiatry untethered from DSM categories, the field still used chemistry to validate its existence. Psychotherapy, arguably the most efficient means for managing much of our anxiety and depression, is time- and labor-intensive. Counseling requires an empathetic and wizened ear to guide the patient to do the work. Ingesting a pill to do that work for you is more seductive, and easier. As Davis writes, even though the industry abandoned the DSM, it continues to strive for a "brain-based diagnostic system." </p><p>That language has infiltrated public consciousness. The team at McLean surveyed 279 patients seeking acute treatment for depression. As they note, the causes of psychological distress have constantly shifted over the millennia: humoral imbalance in the ancient world; spiritual possession in medieval times; early childhood experiences around the time of Freud; maladaptive thought patterns dominant in the latter half of last century. While the team found that psychosocial explanations remain popular, biogenetic explanations (such as the chemical imbalance theory) are becoming more prominent. </p><p>Interestingly, the 80 people Davis interviewed for his book predominantly relied on biogenetic explanations. Instead of doctors diagnosing patients, as you might expect, they increasingly serve to confirm what patients come in suspecting. Patients arrive at medical offices confident in their self-diagnoses. They believe a pill is the best course of treatment, largely because they saw an advertisement or listened to a friend. Doctors too often oblige without further curiosity as to the reasons for their distress. </p>
Image: Illustration Forest / Shutterstock<p>While medicalizing mental health softens the stigma of depression—if a disorder is inheritable, it was never really your fault—it also disempowers the patient. The team at McLean writes,</p><p style="margin-left: 20px;">"More recent studies indicate that participants who are told that their depression is caused by a chemical imbalance or genetic abnormality expect to have depression for a longer period, report more depressive symptoms, and feel they have less control over their negative emotions."</p><p>Davis points out the language used by direct-to-consumer advertising prevalent in America. Doctors, media, and advertising agencies converge around common messages, such as everyday blues is a "real medical condition," everyone is susceptible to clinical depression, and drugs correct underlying somatic conditions that you never consciously control. He continues,</p><p style="margin-left: 20px;">"Your inner life and evaluative stance are of marginal, if any, relevance; counseling or psychotherapy aimed at self-insight would serve little purpose." </p><p>The McLean team discovered a similar phenomenon: patients expect little from psychotherapy and a lot from pills. When depression is treated as the result of an internal and immutable essence instead of environmental conditions, behavioral changes are not expected to make much difference. Chemistry rules the popular imagination.</p>