Organoids Offer Clues to How Brains are Made in Humans and Chimpanzees

Rory Christian

Mr. Ippolito

Current Event 5

October 16, 2019

Sanders, Laura. “Organoids Offer Clues to How Brains Are Made in Humans and Chimpanzees.” Science News, 16 Oct. 2019, www.sciencenews.org/article/organoids-brains-human-chimpanzee-development.   

It has been recently discovered that "brainlike blobs" can reveal similarities and differences among primate brain development. More technically defined as cerebral organoids, these three dimensional clumps of cells are used to replicate the complexity of an organ and can provide insight into early brain development in humans and chimpanzees. To make these cerebral organoids from chimpanzees, cells were first extracted from the blood a typical blood draw. White blood cells in these vials were then programmed to become stem cells and finally arranged into blobs of brain cells. "From that, we get something that really looks a lot like the early brain," says Gray Camp, a stem cell biologist at the Institute of Molecular and Clinical Ophthalmology Basel in Switzerland. After examining the human and chimpanzee organoids, there was no obvious difference in the appearance. However, a look at how the genes behaved in the two organoids, and how it changed over time, sparked interest in the scientists. For one, chimpanzee organoids and nerve cells appeared to mature faster than the human ones. Although it has always been known that humans take longer to develop when compared to other species, this comparison especially emphasized it. The alignment of the different growth times allowed the scientists to explore the genes that behaved differently for each species and the difference in DNA usage. It was found that some stretches of DNA are missing in people, but present in chimpanzees. Areas of the chimpanzee that contained these stretches, were ready to act on certain proteins that allowed for a faster development rate.

This development is significant in the world of neuroscience and even evolution. Understanding how and why our brain differs from species that we are closely related to, is important in the development of science and brain development. "Studies of organoids hold promise, particularly for their ability to reveal developmental processes that would otherwise be hidden, such as the brain's earliest days as it develops in the womb," says Paola Arlotta, a neurobiologist at Harvard University. Although the "brain blobs" are only approximations of the real thing, they allow researches to compare and contrast the brain of humans with that of our closest primate.

This article was well written and informative and the summary overall was detailed and descriptive. I specifically enjoyed how engaging the article was; this was partly due to its excellent organization and clarity. There were, however, a few aspects that could be improved upon. The author included a descriptive summary of how the cerebral organoids were made from chimpanzees; however, they failed to describe how this was accomplished with the human ones. Although it is known that they are made from stem cells, I would have liked more of a description of this process. Finally, I was a little bit underwhelmed by the conclusion and results of the article. I would have liked to have seen a more detailed analysis of the findings and even a stronger conclusion. Overall, I found this article very compelling and excited for the future of neuroscience.

“Implanted Memories Teach Birds a Song.”

Amanda Troy 

AP Biology 

Mr. Ippolito 

10/6/19 

UT Southwestern Medical Center. “Implanted Memories Teach Birds a Song.” ScienceDaily,    

ScienceDaily, 3 Oct. 2019, www.sciencedaily.com/releases/2019/10/191003141557.htm.

This article discusses a study involving song birds held at UT Southwestern which shows that memories can be implanted in the brain to teach vocalizations-without any lessons from the parent. Many of the aspects of vocal learning remains a mystery. Scientists have been wondering: how does the brain encode the memories needed to imitate our parents’ speech? And can scientists intervene when the process goes amiss? Dr. Todd Roberts, a neuroscientist with UT Southwestern’s O’Donnell Brain Institute stated, “This is the first time we have confirmed brain regions that encode behavioral-goal memories -- those memories that guide us when we want to imitate anything from speech to learning the piano," (UT Southwestern Medical Center, pg 1). The scientists activated a circuit of neurons through optogenetics, a new tool that uses light to monitor and control brain activity. The researchers used Zebra finches since they share many of the human stages of vocal development. Early in life, the birds hear their fathers sing, eventually memorizing the notes. They learn to replicate the behavior after practicing a countless number of times. The birds used the memories that the team encoded to learn syllabus of their song, with the duration of each note corresponding to the amount of time the light kept the neurons active. The findings break new ground on establishing how behavioral-goal memories are created and their special role in learning vocalizations. Dr. Roberts said, "It has been hard to study these kinds of memories in the lab because we haven't known where they're encoded," (UT Southwestern Medical Center, pg 2). These answers were found, however, in the testing connections between sensory motor areas of the brain. Researchers used Optogenetics to manipulate neuron activity in the NIf brain region and to control the information it sends to the HVC, the part of the brain implicated in learning from auditory experience. Besides documenting the NIf's role in forming syllable-specific memories, Dr. Roberts' team found that these memories were being stored elsewhere in the brain following their formation. Scientists showed this by cutting the communication between the NIf and HVC at different points of the learning process: Zebra finches that had already formed the memory could still perform the song, however,  those that were tutored after the neural communication was cut failed to copy the song. Dr. Roberts stated that his lab will observe other brain regions that hold different information to the HVC to hopefully gain a better understanding of how additional properties of behavioral-goal memories are created. 

This study is of much importance as it provides eye opening clues regarding where to look in the human brain to better comprehend autism and other conditions that affect language. Nevertheless, this recent discovery is extremely notable because it introduces new paths of research to find more brain circuits that influence other aspects of vocalization, including pitch and sound order. Dr. Roberts says that if we figure out the other pathways, we could hypothetically teach a bird to sing its song without any interactions from its father. However, Dr. Roberts notes that we're a long way from being able to do that. By mapping the neural processes involved as birds learn mating songs, scientists hope to someday use that knowledge to target particular speech genes that are disrupted in patients with autism or other neurodevelopmental conditions. 

A weakness of this article is the order of information. While the article had separate sections for each topic, the information in each section were a bit repetitive at times, mixing the more general information with the more complex. An improvement that can be made is to have the article to begin with broader information about the background of song birds’ processes of vocal learning and then continue to get more complex and detailed, without having to repeat the same general information again. A strength in this article is that it thoroughly described the complexity to the aspects of the research. It discussed the scientific background of processes of vocal learning in songbirds, a complex concept to understand. I also appreciated how the article connected this study to the positive impact it will have on our society, as this research will lead to more insight on neurological disorders. 

Maryam Shanechi Designs Machines to Read Minds

Eve Sullivan
AP Biology
10/7/19
Current Event 4

Temming, Maria. “Maryam Shanechi Designs Machines to Read Minds.” Science News, 2 Oct. 2019, www.sciencenews.org/article/maryam-shanechi-sn-10-scientists-to-watch.

The article “Maryam Shanechi Designs Machines to Read Minds” explains the relevance of a fascinating new study by neuroscientist Maryam Shanechi. The study primarily revolved around the utilization of a brain-machine interface to stimulate cells and thus alter one’s mood. A brain-machine interface is essentially a device that translates neuronal signals into commands, which can control hardware such as a robotic arm. These interfaces have given humans a limited ability to control robotic limbs for almost twenty years. With Shanechi’s specially-designed brain-machine interface, however, she can track individual nerve firings with much more accuracy. Her new system was tested on a group of monkeys, and it was discovered that the new interface could predict their motions with significantly greater precision than the old ones. After this breakthrough, Shanechi continued to create new algorithms to turn thoughts into motions. One study has already proven the usefulness of the improved brain-machine interfaces; after studying people’s brain activity for several days, a computer algorithm was able to use nerve cell firings to predict their moods with the correct results. These algorithms have the potential to help millions of people in the future by detecting their mood and finding out how to change it. 

Shanechi’s discoveries could have an enormous impact on our modern society. Mental manipulation by the brain-machine interfaces would allow for improved treatment for patients with psychiatric disorders by guiding them into healthier mental states. The device would seamlessly analyze a patient’s symptoms and alter them for the better. Psychiatric disorders impact a great number of people in the United States; over 40 million people suffer from anxiety, which is 18.1% of the country’s population. 6.7% of adults in the United States have depression. With the new technology being currently developed, anyone impacted by these disorders could receive treatment as opposed to the few people who currently respond to existing therapies. Shanechi said, “what I really enjoy is to see a mathematical concept making its way toward making a difference in people’s lives.” If her device works as expected, Shanechi may accomplish her goal and improve the lives of millions of people. 

Maria Temming’s article was successful at conveying the importance of this topic and bringing to light the potential for Shanenchi’s new discovery. The writing was both formal and analytical, which helped to develop a thoughtful vision of the future. It was also very detailed and provided the background and results for several experiments. However, I feel it could be improved by explaining brain-machine interfaces in more depth and talking more about possible negative aspects of the technology. Though the article focused on many of the positive effects of the machine, it did not go into the “mind-control” aspects many are concerned about. The article also included a lot about Shanechi’s personal life, but I think adding more information regarding the technology would have been a better portrayal of the paper’s primary focus. Overall, however, it did an excellent job of explaining the potential for an exciting new scientific development.

Student Video Contest

 

Genetically Tailored Instruction Improves Songbird Learning

Ellyn Paris 

AP Biology 

9/24/19

Current Event 3

University of California - San Francisco. "Genetically tailored instruction improves songbird learning: Results lend support to arguments for 'personalized education' in classrooms, researchers say." ScienceDaily. ScienceDaily, 18 September 2019. <www.sciencedaily.com/releases/2019/09/190918112428.htm>.

This article discusses the findings of a research experiment done by UC San Francisco on birds and their song-learning abilities. The experiment was done to understand how genes affect learning potential, but studying this using human subjects is very complex, therefore birds were used. A 2018 study conducted by David Mets and Michael Brainards determined that the way that Bengalese finches perform their songs is influenced by genetics. Birds whose ancestors sang at slow tempos are unable to learn songs that are average or high tempo, and vice versa. However, when the computer “tutoring” program that was used to teach birds a song was tailored to what the finches were genetically built to sing, the subjects learned their songs effectively. The article connects this with the fact that individuals learn differently, therefore a standardized school system cannot be beneficial for all. Since genetic information is different for each person, one style of education is unable to suit all students. After studying finches’ ability to learn different tempo songs according to their genetic information, Brainard and Mets wish to determine the specific genetic variants that keep the finches who are predisposed to perform songs at a certain tempo from performing at another tempo. In doing this, the scientists wish to add to the working studies of how genes and experience influence an animal’s individuality.

As mentioned above, this study connects to how each individual is predisposed to learn a certain way. While the experiments focused on Bengalese finches, the results can be applied to human students across the globe. One style of teaching might help one part of the population, but will not be beneficial to another. Since each individual learns differently, it is important to have personalized teaching styles that consider all types of students. The style of education taught in most classrooms is problematic, since while some students may thrive under this teaching method, many are struggling and experience anxiety, extreme stress, and other concerning symptoms. Our society must find a way to teach their children in a better and more personalized way.

The article was very interesting, and was written with well chosen words and an organized structure. At the end of the article, the author included what the scientists who conducted the study wish to do in the future. I found this to be a good idea because it allows the reader to better understand the purpose of the study and what to expect from Mets and Brainard in the future. The article mentioned in the beginning the connection between the experiments on the birds and what this means for human students, but did not go further into this topic throughout the article. I believe this is a flaw that should be fixed, since the underlying message was extremely important and should have been discussed more. In order to improve the article, I suggest the author includes more lines about what the study means for humans.

A Newly Identified Protein May Be the Key to Vanquishing the Common Cold

Misha Pustovit 

Mr. Ippolito 

AP Biology C Even

24 September 2019

Makin, Simon. “A Newly Identified Protein May Be the Key to Vanquishing the Common Cold.” Scientific American, 17 Sept. 2019, https://www.scientificamerican.com/article/a-newly-identified-protein-may-be-the-key-to-vanquishing-the-common-cold/#. 

This article details the discovery of a protein that may be essential to the function of viruses such as the Common Cold. The SETD3 protein is found in the human body and plays a role in Actin methylation, a process that allows smooth muscles to contract during childbirth. However, certain viruses have found a way to use the protein to create copies of themselves inside their host cell. This means that the removal of the protein should prevent these viruses from taking over the host organism.

In a study, microbiologist Jan Carette and his team investigated the dependence of viruses on the SETD3 protein. They created cells that lacked the protein and found that viruses were a thousand times less effective at replicating inside the protein-deficient cells compared to the control cells. This was true for all seven types of human enteroviruses that were tested.

This discovery means that turning off the SETD3 gene may be an effective way to target viruses in the human body. However, the SETD3 protein may have uses that scientists may not have yet discovered, and removing the protein from human cells may have very serious unforeseen side effects. Mice from which the protein was removed had difficulty giving birth, for example. If the protein has other functions, completely removing it may be detrimental to the health of the subject. Instead, a possible alternative would be to reduce its presence by an amount that would preserve its functionality while inhibiting the replication of viruses within the host. However, the only way to determine if this is true would be through a human trial.

The information in this article was presented in a way that provided many important details while being relatively easy to follow for those who are not scientifically inclined. Although the names of proteins, genes and viruses are listed, the big picture is made clear to the reader regardless of their understanding of biology. However, the article would have been even easier to understand if the author had included images or diagrams of the proteins or viruses which they mentioned. The transition from a broad summary of the issue to more technical terms is smoothly implemented and easy to understand.

A Swifter Way Towards 3D-Printed Organs

Catherine Proskoff           9/18/19

AP Biology       Current Event #3

Brownell, Lindsay. “A Swifter Way Towards 3D-Printed Organs.” Wyss Institute for Biologically Inspired Engineering, 9 Sept. 2019, wyss.harvard.edu/a-swifter-way-towards-3d-printed-organs/.

In the article “A Swifter Way Towards 3D-Printed Organs” Lindsay Brownell described how researchers from Harvard's Wyss Institute for Biologically Inspired Engineering and John A. Paulson School of Engineering and Applied Sciences (SEAS) have recently taken a major step forward that may soon make 3D-printed organs a reality. To date, all 3D-printed human tissues have had several issues which have prevented them from functioning successfully in human organ repair and transplant. These tissues lack cellular density, are too small for organ-level functions, and most importantly, they do not have an effective oxygen delivery method to nourish the cells within the tissue. Fortunately, researchers from Harvard’s Wyss Institute and SEAS have managed to develop a technique known as sacrificial writing into functional tissue, or SWIFT. The process of creating an organ using this technique begins with the formation thousands of stem-cell-derived organ building blocks, or OBBs, which are derived from adult induced pluripotent stem cells and are capable of forming organ-specific tissue. The OBBs are combined with an extracellular matrix solution, forming a living matrix, and compacted in a mold via centrifugation for a high cellular density. The substance within the mold is cooled until it can be manipulated, but is strong enough to hold its shape. It is at this point that the SWIFT technique is used - a nozzle containing sacrificial gelatin “ink” moves through the matrix gently moving cells aside without damaging them. With this method,single and branched channels can be printed in any direction. The matrix is heated at 37℃, at which point the matrix stiffens and solidifies, while the ink melts and can be washed out. This leaves the organ with a series of channels, which can be used to transfer oxygen and other necessary nutrients throughout the tissue.

Using this method, the team was able to successfully “print” a perfusable cardiac tissue that was able to beat synchronously over a seven day period. This is a massive achievement which can provide hope for hundreds of thousands of people in need of a transplant. Within the U.S. alone, 20 people die every day waiting for an organ transplant, and over 113,000 patients are currently on organ waitlists. Now more than ever, with heart disease among the ten leading causes of adult death in the United States, organ printing is the miracle that could solve the problem of organ shortage and change hundreds of thousands of lives in the U.S. and around the world. The ability to grow functional human organs outside the body would allow for major advancements in medicine and healthcare, and has a tremendous amount of potential that is yet to be explored.

Brownell’s article was well written and informative. It broke down the complex procedure and ideas of 3D-printing organs and presented them in a simplistic, easily understandable manner. The article described how the benefits of this technology would alleviate, if not solve the problems of organ shortage that exist both in the U.S. and around the world. Brownell’s article also provided a variety of visual media that complemented the article. Images provided additional evidence showing the success of this technology, and a video embedded in the article explained the SWIFT method briefly, complete with even more visual aids. Brownell also provided quotes from both the researchers and directors overseeing the experiments, which clarified what they hoped to achieve and how they wanted to utilize the SWIFT technology. The article was very concrete, and lacked only a description of how long, expensive, and labor-intensive the production of 3D-printed organs would be.