分类： 赛事资讯

A New Cancer Treatment That Is Faster, More Efficient and Less Risky Is Coming: Bacteria Bombs

Bacteria are usually thought of as microscopic, disease-causing nuisances. They have long been seen as something that needs to be washed away with soap and warm water, or killed en masse with hand sanitizer. But what if these stigmatized organisms could be used to fight cancer, the stubborn killer devastating millions of people? Scientists at the University of California, led by Jeff Hasty, are working to genetically engineer bacteria that will infiltrate tumors and kill them. Combined with conventional treatment such as chemotherapy, researchers are hoping bacteria will be very effective at killing tumors and, further, stopping them from spreading. If proven safe and effective, this bacterial treatment could provide a vital victory in the war against cancer.

The immune system regularly patrols the body to find and destroy cancerous cells, but tumors can disguise themselves as normal cells by releasing a protein that tells the body to leave the tumor alone. And so, the tumor hides in plain sight, invading the healthy tissue around it. Tumors use blood vessels that branch all over the surface of the tumor to steal resources. Chemotherapy delivers cancer killing drugs to the bloodstream, but these drugs can only reach as far as the blood vessels reach, and most of the tumor’s blood vessels do not get to the center of the tumor.

This is where the bacteria, specifically salmonella, can come to the rescue. The scientists at the University of California have changed the DNA of bacteria to seek out these tumors, and populate them without invading the rest of the body. The bacteria settle in and start to replicate. But, like little bombs, they soon explode and release “a toxic cocktail” in the words of Dr. Sally Adee. The cocktail contains “three types of cancer-killing drugs: one that destroys cell walls, one that alerts the body’s immune system, and one that triggers cells to die” according to Dr. Adee. This allows the bacteria to attack the tumor directly in a localized way to keep the damage away from other healthy cells. Importantly, it also alerts the immune system to begin its offensive by destroying the tumor’s immunosuppressive proteins. In his Nature Reviews Cancer article, “Engineering the Perfect (Bacterial) Cancer Therapy,” the University of Massachusetts professor Neil Forbes said, “the immune system plays a complicated role in bacteriolytic therapy; it provides a mechanism to guide bacterial accumulation, but also impedes dispersion and efficacy.” Thus the body and these bacteria form a surprising team in their war against cancer.

Of course, this treatment has risks. The main danger is that the bacteria will become the enemy and infect the person. To prevent this, researchers have modified the bacteria to not only thrive in the environment of a tumor, but also to struggle to survive in healthy tissue. This is a revolution in the way people have thought about cancer treatment. Bacteria may soon join the list of unlikely allies in the fight against cancer, joining the ranks of debilitating chemicals and harmful radiation.

Works Cited

Adee, Sally. “Self-Destructing Bacteria Are Engineered to Kill Cancer Cells.” New Scientist, 20 July 2016.

Forbes, Neil S. “Engineering the Perfect (Bacterial) Cancer Therapy.” Nature Reviews Cancer, 14 Oct. 2010.

Williams, Thomas. “New Cancer Treatment? Scientists Have Programmed Bacteria to Kill Cancer Cells in Mice.” The Conversation, 21 July 2016.

Zimmer, Carl. “New Weapons Against Cancer: Millions of Bacteria Programmed to Kill.” The New York Times, 3 July 2019.

From Babbling to Birdsong: What Finches Can Teach Us About Vocal Learning

Imagine listening to Puccini’s “O Mio Babbino Caro,” as performed by a two-month-old baby, or Bizet’s “Habanera” crooned by a toddler. In some sense, that is what you hear when a baby finch practices its singing. Recently, scientists have studied how juvenile finches learn their songs, and their findings could teach us a thing or two about the way our own learning works.

Learning to speak is very much like learning to play a violin or a piano. It involves properly controlling the complex muscles that enable speech. In fact, humans and birds share a similar process. Just as a baby learns to say “Mama” or “Dada” by mirroring their parents’ baby talk, juvenile songbirds reproduce their parents’ song — but it’s more like a skipping CD stringing together single notes instead of the full track. Humans and songbirds are more impressionable when they’re young, and their neuroplasticity decreases in transition from adolescence to adulthood. Observing this change in birds could help scientists develop treatments for strokes and other conditions that affect speech and movement.

Michael Brainard, a professor of physiology and psychiatry at the University of California San Francisco, conducted experiments on juvenile Bengalese finches to explore the neurological circuitry behind vocal learning. By observing the finches learning songs from computerized teachers, he was able to stitch together the neural networks that coordinate cognitive and motor control during singing. He discovered that suppressing a region of the brain responsible for motor control, known as the basal ganglia, made the juvenile finches sing a duller tune, as if the glissandos and fortissimos had been taken out of the score. At the same time, variations in pitch were subdued, making the song more monotone. “It looks like this part of the brain is introducing variability — constantly doing things a little differently and then discovering ‘Okay, that sounded really good. I’ll do it that way again,’” Dr. Brainard said. Basically, the juvenile finches’ ability to use trial and error in learning had been eliminated. Whether it’s learning to ride a bike or cook pasta, trial and error helps us get better at certain tasks over time. “You need to try something different to optimize your performance,” Dr. Brainard explained.

Because birds and humans share so many parallels in vocal learning, scientists believe insights into the finch basal ganglia function could be relevant in understanding the way our own basal ganglia works during human speech learning and other types of motor skill performance, especially in diseases. Many illnesses, like Parkinson’s and Huntington’s disease, both directly involve the basal ganglia. “We think it’s probably no accident that the same circuit performing a function and introducing variability in birds might also be a circuit that contributes to abnormalities and movement variability,” said Dr. Brainard. “We can discover general principles that will contribute broadly to understanding how normal learning systems work, and ultimately how to correct function when it goes awry.”

Works Cited

Brainard, Michael S., and Allison J. Doupe. “Translating Birdsong: Songbirds as a Model for Basic and Applied Medical Research.” U.S. National Library of Medicine, 8 July 2013.

Kao, Mini, and Michael S. Brainard. “Lesions of an Avian Basal Ganglia Circuit Prevent Context-Dependent Changes to Song Variability.” Journal of Neurophysiology, U.S. National Library of Medicine, 24 May 2006.

Grunbaum, Mara. “Astonishing Animals That Illuminate Human Health.” University of California San Francisco, 25 Feb. 2021.

Mets, David G, and Michael S. Brainard. “An Automated Approach to the Quantitation of Vocalizations and Vocal Learning in the Songbird.” PLoS Computational Biology, Public Library of Science, 31 Aug. 2018.

Requarth, Tim and Meehan Crist. “From the Mouths of Babes and Birds.” The New York Times, 30 June 2013.

The Peacock Mantis Shrimp: The Ant-Man of Atlantis

Fifty miles per hour. A force of 8,000 G’s. All deployed in under two milliseconds. You’re not looking at a modern-day bullet, but the fastest punch in the animal kingdom.

Dubbed by scientists as “nature’s underwater marvel,” the peacock mantis shrimp has the ability to pierce its prey’s skull and completely cavitate the water around it. However, as fascinating as that sounds, the question still remains: How can this four-inch creature deliver forces 1,000 times its own weight?

In typical fashion, nature doesn’t like to reveal all its secrets, but scientists around the world have managed to attribute this mystery to one factor: its structure. While most man-made materials have their atoms layered on top of each other in an orderly fashion, this shrimp’s club takes a page out of nature’s cookbook by layering its fibers in small varying degrees, forming a spiral-like helicoid structure, capable of withstanding over 2,000 Newtons of force!

Split into three main layers, its club is purpose-built to pack a powerful punch every time. The first layer is composed of a mineral known as hydroxyapatite, the same one found in your hair and teeth; however, in this case, it’s in a more crystalline form, owing to a much harder surface. The second layer is composed of a much softer form of the same mineral albeit with each layer being rotated slightly, forming the helicoid structure that scientists have now come to recognize. The third consists of layers of chitin that prevent the club from expanding upon impact.

But what if we were to implement this into the mainstream market? While scientists and engineers have known about this phenomena for more than half a decade, the research originally conducted by the University of California, Riverside, in 2014 is just starting to trickle down into various corporations. The most complex architecture used in the aerospace industry today revolves around layering sheets of carbon-fiber at zero degrees, 45 right, 45 left and then 90 degrees. However, if we were to layer the same material using a helicoid configuration, the results would be borderline revolutionary!

This would delay internal failure by over 74 percent, increase impact resistance by over 50 percent and improve load-bearing by over 92 percent. Now, you don’t need to be a rocket scientist to understand that those figures can reform entire industries.

However, while figures are one thing, real-life performance is a whole different situation, and it doesn’t fall short. This extraordinary structure allows for much lighter, stronger and cheaper composites, which, when implemented into vehicles, allows them to emit less carbon dioxide and carry a smaller carbon footprint. And while our world is hanging onto life support, this could be the very turning point at which we can make a significant change.

As scientists continue to pluck from the fruits of nature, this discovery merely marks the beginning of a whole new wave of materials to come. From hummingbirds to geckos, we are finally turning a new leaf, falling toward the mystic arts of nature rather than trying to cast away its spells.

Works Cited

Kim, Meeri. “Shrimp’s Shell-Smashing Punch Hands Researchers a Lead on Tougher Materials.” The Guardian, 9 May 2014.

Kwok, Roberta. “This Shrimp Packs A Punch.” Science News, 27 March 2013.

News Channel 3 Staff. “The Mantis Shrimp Changing Composites.” News Channel 3, 19 Nov. 2019.

Scharping, Nathaniel. “How Mantis Shrimp Punch So Hard Without Hurting Themselves.” Discover, 16 Jan. 2018.

Science Daily Staff. “Mantis Shrimp Stronger Than Airplanes.” Science Daily, 22 April 2014.

Treacy, Siobhan. “Materials for Aerospace and Sports Inspired by the Mantis Shrimp’s Club.” Engineering360, 16 Jan. 2018.