A Robot in Human Skin

A Robot in Human Skin

When asked to think of a humanoid robot, it’s very likely that you are imagining the robots featured in the TV show Westworld or the movie Ex Machina: robots that are human-like but not actually human. These images mostly stem from sci-fi, but the real world isn’t too far from producing robots of this kind.

Read More

ACHOO – A Tale of Uninvited Sneezes

ACHOO – A Tale of Uninvited Sneezes

Outside of normal sneezing exists an entirely separate group of sneezing-related phenomena. One particularly common condition that affects up to 35% of Americans is called the photic sneeze reflex. This reflex is conveniently abbreviated as ACHOO (Autosomal Dominant Compulsive Helio-Ophthalmic Outburst syndrome), so named because it involves sneezing in response to sudden increases in light intensity.

Read More

A New Hope for Naltrexone in Managing Opioid Dependence

Thumbnail_2_DS.jpeg

 

In a survey of substance abuse-related hospital admissions taken by the Substance Abuse and Mental Health Services Administration (SAMHSA), a total of 26% of all admissions surveyed were due to primary opioid addiction. Of the 1.7 million cases surveyed, this percentage represents just under half a million cases in which opioid misuse was the primary issue [1]. This staggering proportion underscores the prevalence of opioid dependence in the US and begs the question of what is being done to help those struggling against opioid dependence.

 

One approach to assisting individuals recovering from opioid addiction has been to treat with a maintenance drug. A maintenance drug is a drug prescribed by a healthcare professional that helps reduce the cravings for opioids that often lead to relapse. Current treatments include methadone and buprenorphine, both of which can be thought of as substitute agents for the more addictive substances. While these types of therapies can often help reduce cravings and prevent withdrawal effects, they still carry the risk of abuse due to their pharmacological similarity to morphine and other opioids.

 

Naltrexone, a drug that works to block the receptors that mediate the addictiveness of opioids, has been tested previously as an agent to help patients maintain abstinence from opioid abuse. While its oral form demonstrates some efficacy, its clinical use has been limited due to issues with patient compliance [2]. Two recent studies from groups in the US and Norway have tested a new, injectable version of naltrexone that has shown promise compared to current standards of care [3, 4]. While relapse rates remain high among those recovering from opioid abuse, the continued development of pharmacotherapies in helping to reduce cravings is crucial in the effort to help these patients win back their independence [5].

 

David Shia

Staff Writer, Signal to Noise Magazine

MD/PhD Candidate in Molecular Biology Interdepartmental Doctoral Program, UCLA

 

 

References:

[1] Substance Abuse and Mental Health Services Administration, Center for Behavioral Health Statistics and Quality. Treatment Episode Data Set (TEDS): 2002-2012. National Admissions to Substance Abuse Treatment Services. BHSIS Series S-71, HHS Publication No. (SMA) 14-4850. Rockville, MD: Substance Abuse and Mental Health Services Administration (2014).

 [2] Bart, G. Maintenance medication for opiate addiction: the foundation of recovery. Journal of Addictive Diseases 31(3), 207-225 (2012).

[3] Tanum, L., et al. Effectiveness of Injectable Extended-Release Naltrexone vs Daily Buprenorphine-Naloxone for Opioid Dependence: A Randomized Clinical Noninferiority Trial. JAMA Psychiatry 74(12), 1197-1205 (2017).

[4] Lee, J. D., et al. Comparative effectiveness of extended-release naltrexone versus buprenorphine-naloxone for opioid relapse prevention (X: BOT): a multicentre, open-label, randomised controlled trial. The Lancet 391(10118), 309-318 (2017).

[5] Smyth, B. P., Barry, J., Keenan, E., & Ducray, K. (2010). Lapse and relapse following inpatient treatment of opiate dependence. Irish Medical Journal 103(6), 176-179 (2010).

I Get By With A Little Help From My Friends

Vegetables lend our body a helping hand. Image Credit: Public domain

Vegetables lend our body a helping hand. Image Credit: Public domain

Everyone has their “sick food,” that staple cure-all of childhood, one whose guarded family recipe has been passed through the generations. But in order to extract all the helpful nutrients from these typically veggie-laden foods, our digestive system needs a helping hand. Our gastrointestinal tracts not only digest and absorb nutrients from the food we eat, but also play host to millions of benign microorganisms, collectively known as the “gut microbiome.” They feed as we eat, and in turn assist in digestion and release molecules that affect our bodies. Such secretions, including different types of fatty acids, have been found to specifically impact the immune system. So it’s no wonder that scientists have probed into how these fatty acids affect human health and disease.

 

Cells in the immune system can take on many different functions, two of which are “inflammatory” and “suppressive.” Inflammatory cells promote the attack of foreign, or perceived foreign, invaders, while suppressive ones keep the body’s defenses at bay. Maintaining a balance between these two is critical, and disequilibrium can lead to disease. In the case of multiple sclerosis (MS), the scales are tipped in favor of an inflammatory immune response. This leads to an “overactive” immune system that attacks the patient’s own nervous system. Since the fatty acids released by our microbiome affect our immune system, and an immune imbalance is thought to contribute to the development of MS, Dr. Aiden Haghikia and his team wondered if our gut residents’ secretions could impact MS directly [1].

 

To test their hypothesis, the researchers first looked at naive T cells, cells from the immune system that have yet to decide their function. They treated the cells with two different types of fatty acids: short chain and long chain. While naive T cells exposed to short chain fatty acids became suppressive, those given long chain fatty acids were more inflammatory. Dr. Haghikia and his colleagues then asked if they could apply these findings to a disease model in mice. Would treatment with short chain fatty acids be both preventative and therapeutic, fixing the imbalanced immune system by promoting suppressive T cells? As it turns out, these secretions do have a beneficial effect, but only before disease onset. Mice that had been fed short chain fatty acids prior to MS induction had generally less trouble walking and had more balanced immune systems than untreated mice – that is, they had more suppressive immune cells. However, when mice started receiving short chain fatty acids after their MS became apparent, they saw none of these benefits.

 

We are only just discovering the effects of short chain fatty acids on the immune system. Here, researchers were able to show that, in the context of MS, these molecules may have preemptive beneficial effects. If you recall, fatty acids can be secreted by our little friends in the gut. And what type of diet results in our gut microbiome producing short chain fatty acids? A vegetable-heavy one.

 

 

 

Megan G. Massa (@MegMassa)

Guest Contributor, Signal to Noise

First year PhD student, UCLA Neuroscience Interdepartmental Program with a focus in neuroendocrinology

 

References:                   

[1] Haghikia, A. et al. Dietary Fatty Acids Directly Impact Central Nervous System Autoimmunity via the Small Intestine. Immunity 43, 817–829 (2015).

Biases in Science News: Tracking Down the Source of Exaggerations

Image Credit: Public domain

Image Credit: Public domain

How often have you seen a news headline about a study on the benefits of red wine or dark chocolate only to hear later about a new study that contradicts the first one? While many science stories have strong data and evidence to back their claims, other news headlines come from the type of data that can’t provide a definitive proof of cause-and-effect. [1]. A recent study [2] looked at how journalists write science stories and how these stories can end up as misleading headline science.

The authors determined how statements made in press releases influenced the presence of exaggerations in news stories. An example would be saying that “eating dark chocolate causes fewer heart attacks” instead of indicating that there was a correlation between a group that ate more dark chocolate and the number of heart attacks occurring in that group. This study would only demonstrate a correlation between heart attacks and eating dark chocolate and does not prove that eating dark chocolate was the cause for fewer heart attacks. Researchers looked through 534 press releases prepared by research journals and the corresponding 582 news articles, then identified any statements or advice not included in the manuscript.

Results show that 25% of the press releases included more explicit advice compared to the original paper. 20% of the press releases also misinterpreted a correlation study as a study that presented a cause-and-effect relationship. The results also demonstrated that journalists would not tend to include over-exaggerations if the exaggerations were not part of the original press release.

This paper shows how exaggerations in press releases can create misleading headlines in science news stories. Since journalists may not have the expertise or time to fact-check statements from a press release, any information included in a press release should be precise, and any claims made should not be exaggerated from the original study. Headline news is crucial for communicating science, but if the stories are inaccurate or over-exaggerated, it can erode people’s trust in the scientific method.   

- Erica K. Brockmeier
Toxicology post-doc / Aspiring science writer
@EKBrockmeier

 

References:
[1] Aschwanden, C. Science Isn’t Broken. Five Thirty Eight Science and Health (2015, Aug 19). Accessed on 2017, Feb 24. https://fivethirtyeight.com/features/science-isnt-broken

[2] Sumner, P. et al. Exaggerations and Caveats in Press Releases and Health-Related Science News. PLoS ONE 11(12), e0168217. doi:10.1371/journal.pone.0168217 (2016).

Of Songs and Circuits: Freshly Made Neurons Make For Freshly Made Music

Image Credit: “WHITE-CROWNED SPARROW” by Gary L. Clark is licensed under CC-BY-SA-4.0.

The study of how new neurons are made in the adult brain (adult neurogenesis) has received much attention because newborn neurons can integrate into and reshape preexisting neural circuits, making circuits “plastic.” It's not clear, though, how neural plasticity relates to the behavior produced by a particular neural circuit. Songbirds exhibit seasonal plasticity: during breeding season they have an increased number of neurons called Higher Vocal Center neurons (HVCs), which connect different regions of the brain important for producing songs. The relationship between cyclic addition/removal of HVC neurons and song production in male white-crowned sparrows was addressed by Rachel Cohen and colleagues. To compare the number of newly added HVC neurons to song quality in breeding versus non-breeding sparrows, they first had to count the number of newly added HVCs. They then compared this to the types of songs the sparrows sang. Cohen and colleagues found a direct correlation between song structure and HVC neuron number. When HVC neuron number goes down, song structure degrades (corresponding to non-breeding birds), but as new HVCs are added, song structure recovers (corresponding to breeding birds). Generation of new HVC neurons was also correlated to increases in the amount of a steroid hormone known to be important for neuron survival. The authors provide highly suggestive evidence that the underlying basis for circuit plasticity in this song circuit is the regeneration of HVC neurons, a process controlled by hormones. The seasonal plasticity of songbird neural circuits may also serve as a new model for understanding how number of neurons and the connections they make produces specific types of behaviors.

Jennifer Lovick (@drjkyl)
Senior Editor, Science in Entertainment, Signal to Noise Magazine
PhD, Molecular, Cell, and Developmental Biology

References:

Cohen, R.E., Macedo-Lima, M., Miller, K.E., Brenowitz, E.A. Adult neurogenesis leads to the functional reconstruction of a Telencephalic neural circuit. J Neurosci 36, 8947-8956 (2016).

Monstrous Mutations in Our Creepy, Crawly Friend: The Fruit Fly

Monstrous Mutations in Our Creepy, Crawly Friend: The Fruit Fly

The unforgettable final scene of The Fly features a poor little fly stuck in a spider's web, screaming “Help me! Help me!” before being crushed to death. Although scientists in the real world don’t have disintegrator-integrator devices that could accidentally swap body parts between humans and flies, there are many remarkable genetic mutations that scientists can study to better understand how our bodies develop and why we have certain diseases. Many of these were first discovered in the fruit fly. Here are a few of these monstrous mutations for your viewing pleasure - hope they don’t give you nightmares!

Read More

Cadaver Exome Sequencing Brings Modern Medicine to Anatomy 101

Modern genetics is finally finding its way into medical school.

Following our advances in understanding the human genome during the last 30 years, American medical education is entering an era of change, where the practice of genetics and genomic medicine is increasingly shaping the new landscape of physician training. Recognized nationally as an important education initiative, genomic medicine programs are being introduced by medical schools across the country into first- and second-year curriculum. The goal is to train the next generation of physicians to understand how to utilize genomic technology and what insights it can offer for a patient's condition; however, study of this complicated and highly personal (and some argue, private) data can be difficult to incorporate into the classroom.

Read More

Repair A Broken Heart with Your Skin

Images compiled by Xin Liu.

When all other treatments fail, heart failure patients may be treated with a heart transplant, but finding a genetically matched donor can take more time than the patient has remaining. For decades, medical researchers have been asking whether we can find an alternative to repair a broken heart. It turns out the remedy may lie in patients’ own cells: through the process of transdifferentiation, we can transform one type of cell into another. The new cells can then be transplanted into the damaged heart. A recent experiment discovered that a cocktail of nine chemicals, “9C,” can transform cells efficiently [1]. Scientists grew human skin fibroblasts—an abundant cell type that maintain the layered structure of skin—in a petri dish with 9C and other molecules that encourage cardiac cell growth. After a period of time, the fibroblasts turned into heart muscle cells: they gathered into well-organized stripes, they contracted together the way a complete heart beats, and they successfully repaired a damaged heart when transplanted into a mouse. These morphological and functional changes may be caused by the ability of 9C to alter genomic structures and gene expression. DNA is normally wound tightly around protein molecules, keeping it compact; 9C can loosen these structural proteins, allowing the activation of genes essential for heart function. Compared to prior genetic engineering methods, this chemical method drastically improves the efficiency of transdifferentiation. While the standard genetic engineering method only converted 0.1% of fibroblasts into cardiac cells, 9C could convert more than 97% of the cells [2]. Although this method is still in its infancy, these results suggest it may be a promising approach to healing heart failure.

Xin Liu
Guest Contributor
PhD Candidate, Molecular Biology Interdepartmental Doctoral Program, UCLA
 

References
[1] Cao, N. et al. Conversion of human fibroblasts into functional cardiomyocytes by small molecules. Science, 352, 1216–1220 (2016).
[2] Srivastava, D. et al. Recent advances in direct cardiac reprogramming. Current Opinion in Genetics & Development 34, 77–81 (2015).

 

Zombie Genes: New Evidence Points to Genetic Life After Death

Image credit: “Internal anatomy of a fish (cutaway diagram)” by Alberto Rava is in the public domain. “A section of DNA” by Michael Ströck is licensed under CC Attribution-ShareAlike 3.0. Images modified by Malika Kumar.

What does it mean to die? The exact nature and definition of death has been a mysterious and often hotly debated topic since the times of the earliest human cultures. In a new study from the University of Washington in Seattle, a group of scientists has shown that the lives of our genes may far outlast our own lives [1].

After an animal dies, many of its cells can remain alive for many hours, or in some cases even days, calling into question what kind of processes continue to occur in these cells [2]. Alexander Pozhitkov and colleagues set out to determine whether an animal’s genes were turned off abruptly after death, or whether they slowly faded like a flashlight running out of battery. Pozhitkov’s team examined most of the genome to examine which genes were turned on and off in zebrafish and in the brains and livers of mice for up to 4 days after their death. What they found was surprising - the team discovered that expression of a large group of the genes they looked at was actually elevated even 48 hours after death.

Some of these upregulated groups of genes appeared to indicate cells “gasping” for life after the organism had died around them. These groups included genes involved in processes such as the cell’s stress response, cell death, and the cell’s response to oxygen deprivation. However, other groups of upregulated genes were more unexpected. These groups included genes involved in development of embryos and genes associated with cancer.

Pozhitkov and his colleagues stressed that rather than being part of a larger survival strategy for cells, the upregulation of many of these genes that occurred after the death of mice and zebrafish may simply be a product of the cell no longer having the ability to control its cellular processes. Regardless, the findings will potentially shed light on the processes by which a cell controls its genes, and may have profound implications for our ability to better understand health issues associated with organs transplanted from a recently deceased person into a living patient. Additionally, the finding that certain genes are turned on and off at different times after death may help forensic scientists more accurately determine when a victim died.

In short, be on the lookout: Pozhitkov’s findings may soon be coming to a TV near you on Grey’s Anatomy or CSI.
 

- Jeff Maloy (@JeffreyMaloy)
Staff Writer, Signal to Noise Magazine
PhD Candidate, Microbiology

 

References:
[1] Pozhitkov A.E., Neme R., Domazet-Loso T., Leroux B.G., Soni S., Tautz D., Noble P.A. Thanatotranscriptome: genes actively expressed after organismal death. Preprint in BioRxiv. (2016). DOI: 10.1126/science.aaf5802

[2] Singh M., Ma X., Amoah E., Kannan G. In vitro culture of fibroblast-like cells from postmortem skin of Katahdin sheep stored at 4 °C for different time intervals. In Vitro Cell Dev Biol Anim. (2011). DOI: 10.1007/s11626-011-9395-
 

Calling a Microscopic Quorum: How Fungi Communicate

C. neoformans as single cells. Image credit: Gross L (2006) Iron Regulation and an Opportunistic AIDS-Related Fungal Infection. PLoS Biol 4(12): e427. doi:10.1371/journal.pbio.0040427.


Microbes find strength in numbers. Rarely alone, they live in communities and share resources by coordinating their biological processes. Just as governing bodies require a quorum, or a minimum number of people present, before deciding something on behalf of the entire group, many species of microbes must establish a quorum before coordinating their behavior. Microbes do this through quorum sensing, in which they release signaling molecules such as hormones or small proteins into the surrounding area and then sense the concentration of those signals. As more microbes enter the environment, the concentration of the signaling molecule will increase. Once the microbes sense that the concentration has met a certain threshold, they will initiate a particular biological process.


Microbes often use quorum sensing to determine when to release virulence factors, molecules that will help them overwhelm their target and establish an infection. They only want to spend energy making a virulence factor when there are other cells present because if too few microbes are present, they will not make enough virulence factors to successfully infect their target, and thus will have wasted energy. Quorum sensing systems have been very well characterized in bacteria but not as well in other microbes. In a recent study in the journal Cell Host & Microbe, Homer and colleagues identified and characterized a quorum sensing system in a eukaryotic microbe, the pathogenic fungus Cryptococcus neoformans, which is the most common cause of fungal meningitis [1]. They found that fungal cells with a mutation in the quorum sensing signaling molecule gene, qsp1, were less successful at infecting mice than C. neoformans cells with a fully functional quorum sensing signaling molecule. Through a series of experiments, they elucidated other components of the quorum sensing pathway and found that qsp1 functions inside the fungal cell to control virulence. Previous work identified a quorum sensing system in the pathogenic fungus Candida albicans, but the quorum sensing molecule discovered is produced by many different organisms [2]. Because the newly discovered quorum sensing system described here is specific to C. neoformans, it presents the unique opportunity to develop strategies to specifically disrupt the ability of C. neoformans to cause disease.


-Stephanie DeMarco (@sci_steph)
Staff Writer, Signal to Noise Magazine
PhD Candidate, Molecular Biology

References:

[1] Homer CM, Summers DK, Goranov AI, Clarke SC, Wiesner DL, Diedrich JK, Moresco JJ, Toffaletti D, Upadhya R, Caradonna I, Petnic S, Pessino V, Cuomo CA, Lodge JK, Perfect J, Yates JR 3rd, Nielsen K, Craik CS, Madhani HD. Intracellular Action of a Secreted Peptide Required for Fungal Virulence. Cell Host & Microbe. (2016). DOI: 10.1016/j.chom.2016.05.001.

[2] May RC. Custom-Made Quorum Sensing for a Eukaryote. Developmental Cell. (2016). DOI: 10.1016/j.devcel.2016.05.014.

The Discovery of Gravitational Radiation and Why It Matters

Gravitational wave signal detected by LIGO.
Image credit: LIGO, NSF, Aurore Simonnet (Sonoma State U.)

This Wednesday, the Laser Interferometer Gravitational Wave Observatory (LIGO) announced the second detection of gravitational radiation emanating from a merger of two black holes. This follows the initial discovery of gravitational radiation in February [1]. But why should any of that matter to you? We can't feel our bodies being squeezed by gravitational waves. The discovery of gravitational waves is important because it confirms that the laws of physics work the way we always thought they did. We've been talking about gravitational waves since the early 20th century, when Einstein first posited that the force of gravity might interact directly with space and time [2]. This concept of space and time interwoven as a “fabric” began with his theory of general relativity, and wasn't confirmed until February of 2016 (and again on Wednesday). The detection of gravitational waves doesn't just confirm Einstein's theory on space-time; it also confirms the existence of black hole mergers - extraordinarily energetic events in which two dead stars, each much larger than our Sun, enter a “death spiral” and eventually collide with one another. We're seeing the universe not only in electromagnetic radiation that propagates through space (light), but in gravitational radiation that propagates through the very fabric of space-time itself. It's like discovering a new color, or a new frequency of sound. This amazing technology ushers in a new era of astronomy, where we can now see the universe in an entirely different way.

Laura Haney (@LauraVican)
Signal to Noise Co-founder and COO
PhD, Physics and Astronomy

References:
[1] P. Abbott et al. (LIGO Scientific Collaboration and Virgo Collaboration), Observation of Gravitational Waves from a Binary Black Hole Merger. Phys. Rev. Lett. 116, 061102 (2016).

[2] Einstein, A.: Über Gravitationswellen. In: Sitzungsberichte der Königlich Preussischen Akademie der Wissenschaften Berlin (1918), 154–167. [English translation]
 


 

Predicting Heat Waves Using the Ocean

Heat wave illustration (Source: U.S. National Weather Service, http://www.srh.noaa.gov/jetstream/global/hi.htm)

Heat waves in the United States have become a problem over the past decade. According to the Center for Disease Control and Prevention, from 1999 to 2010, more than 600 people on average died annually in the US from heat-related causes. Relief, though, seems to be emerging. New research published this past week suggests that major heat waves in the US may be predictable two months before they hit. Climatologists from the National Center for Atmospheric Research combed through decades of data and connected sea surface temperature patterns in the North Pacific Ocean to subsequent extremely hot days occurring around 50 days later. The physical connection between sea surface temperature and hot days, though, remains unknown. Scientists think one possibility is that the sea temperatures may be affecting the movement of the jet stream, a fast and narrow air flow in the upper atmosphere that planes often hitch a ride on. The jet stream also helps organize the high-pressure air masses that typically cause extreme heating, so it's a likely suspect for connecting sea surface temperatures to future heat. The connection, though, as the researchers stress, is not a guarantee; the sea surface temperature pattern indicates that a heat wave is likely to occur, not that it definitely will. Still, the correlation is strong enough to make this research invaluable for forecasting and protecting those who may be exposed to extreme heat. 
 

Sean Faulk
Staff Writer, Signal to Noise Magazine
Graduate Student, Earth, Planetary, and Space Sciences

References:

McKinnon, K.A., et al. (2016). Long-lead predictions of eastern United States hot days from Pacific sea surface temperatures. Nature. DOI: 10.1038/ngeo2687

A Planet of Two Surfaces

Artist depiction of 55 Cancri e orbiting its star. (Source: University of Texas, NSF, NASA, http://antwrp.gsfc.nasa.gov/apod/ap040901.html)

Searching for exoplanets, or planets around other stars, can be agonizing. The small, rocky ones, which are tantalizing as they most closely resemble Earth, are the hardest exoplanets to find because they are so small compared to their host stars. But astronomers are discovering more about these worlds, and recently, a team from the University of Cambridge completed the most detailed heat map of a small planet yet: a rocky exoplanet about twice the size of Earth and forty light years away known as 55 Cancri e. Orbiting very close to its star, 55 Cancri e is inhospitable to life but its close orbit has another effect: the planet’s rotation is locked such that the same hemisphere always faces the star, just as the same hemisphere of the Moon always faces the Earth. This splits the planet’s surface into two sides, one of permanent ‘day’ and the other permanent ‘night.’ According to a new study using infrared data from NASA’s Spitzer telescope, the temperature difference between these two sides on 55 Cancri e is as extreme as it gets, with the day side reaching 2500 degrees Celsius under the endless scorch, while the night side chills at a relatively frigid 1100 degrees. The day side is so hot that the surface pulses with riverlike flows and pools of molten lava, while the night side’s surface remains solid rock. The astronomers believe that with such a small distance between planet and star, the extreme stellar heat may have blasted off the planet’s atmosphere, cutting off any atmospheric circulation and thereby preventing heat from traveling from the hot side to the cool. Technology hasn’t caught up with the theory yet - researchers will have to wait for the next generation of space telescopes to get a look at the atmospheres of small worlds such as this one as they continue to hunt for more planets like Earth.

- Sean Faulk
Staff Writer, Signal to Noise Magazine
Graduate Student, Earth, Planetary, and Space Sciences

References:

Demory, BO., et al. (2016). A map of the large day–night temperature gradient of a super-Earth exoplanet. Nature. DOI: 10.1038/nature17169