Short stories and links shared by the scientists in our community
A traditional Chinese medicine successfully protected neurons from amyloid-induced death
Grandma might have the right idea when bringing Jell-O salad to every church potluck.
Gelatins are animal-derived protein fragments created by breaking down collagen — a protein found in connective tissues like skin and ligaments.
Gelatins are also widely used medicinally, from skincare to joint pain. But traditional Chinese medicine also claims that they protect the brain against deteriorating diseases such as Alzheimer’s disease. And a recent study published in Frontiers in Pharmacology put this historically anecdotal remedy to the test.
Researchers first mimicked Alzheimer’s disease in a dish by treating lab-grown cells with a toxic protein fragment that accumulates in patient brain cells, called amyloid-beta. And like human Alzheimer’s disease, amyloid-beta treatment induced profound cell death in this model. But, surprisingly, gelatin treatment completely protected these brain-like cells from this toxicity.
To understand how gelatins are neuroprotective, they turned to mitochondria — the powerhouses of the cell. Mitochondria are cellular structures that generate energy in the form of a molecule called ATP. Because healthy cells need ATP to function, mitochondrial dysfunction is harmful to cell survival and the primary cause of brain cell death in Alzheimer’s disease.
The researchers, therefore, hypothesized that gelatins prevent amyloid-beta-induced cell death through mitochondrial protection. Indeed, the gelatin-treated mitochondria showed reduced structural damage, improved ATP production, and lower oxidative stress. Furthermore, they believe gelatins exert these protective effects by blocking excessive calcium from entering the cell, which can trigger mitochondrial damage, oxidative stress, and ultimately cell death.
Of course, while these results are exciting, the human brain is a little more complex than a dish of cells, and more work is necessary to determine the therapeutic potential of gelatins in human disease.
Yeast cells can produce large amounts of proteins for industrial and therapeutic use, but they sometimes get overworked
Photo by Jason Weingardt on Unsplash
Saccharomyces cerevisiae, commonly known as yeast, is a biological workhorse. It has been used by humans for thousands of years to brew beer, make wine, leaven bread, and, more recently, to produce large amounts of proteins for therapeutic uses and enzymes for industrial applications.
While yeast is often the organism of choice for making large amounts of a protein of interest, there can be problems when protein production is scaled. The unfolded protein response, or UPR, is one of these issues. When yeast cells try to fold large numbers of proteins, their cellular machinery can become overworked, triggering the UPR. Hundreds of genes are turned on rapidly in an effort to decrease the amount of unfolded protein. A fine line needs to be maintained between making enough protein and not triggering a large UPR, which typically results in decreased yields.
In a recently published study in ACS Synthetic Biology, researchers developed a sensor to monitor the UPR in real time. They engineered a fluorescent protein that turns on when the UPR is activated. They then characterized this sensor in cells with proteins produced at different levels and with configurations known to elicit the UPR. They found that the UPR is caused by both how challenging a protein is for the yeast cells to fold, and how much of it is being produced.
Triggering of the UPR is a limitation in protein production that many industries rely on. Development of this sensor gives a real-time readout that could be useful for scientists and engineers trying to maintain the line between maximal protein production and the health of the yeast cells producing them.
Scientists have debated whether the scientific progress justified the invasiveness of the procedure
Image by Karsten Paulick from Pixabay
Males from just a few animal species, namely seahorses and some of their relatives, are known to get pregnant. New research, currently published as a pre-print awaiting peer review, documents the first recorded instance of a male mammal giving birth from a transplanted uterus.
In the study, male rats were surgically prepared to nurture a transplanted uterus with embryos. The project yielded a low (under 4 percent) success rate, but the male rats delivered pups via C-section that grew without any reported complication. While some have excitedly associated the experiment’s success with the possibility of human application, the lead researcher has repeatedly pleaded online to not associate the study with potential male human pregnancy. Regardless of such prospects, this paper has gained tremendous attention for its ethical ramifications.
The procedure and the results triggered an avalanche of tweets questioning its ethics. Scientists debated whether the scientific progress justified the invasiveness of the procedure — for it to work, the male rat was surgically joined to a female rat so that they shared a circulatory system (called parabiosis). One scientist raised concerns on whether this study is indicative of science turning into an entertainment business, according to reporting in Nature. The lead researcher responded by reassuring that, “[the] animals did not have any painful symptoms such as screaming during the entire experiment” and asked that people “... please don’t bring non-scientific factors into scientific research.”
Aside from the sensational outcome of the paper, it also highlights that male rats' pregnancies were only successful when attached to a pregnant female and that the rats sometimes carried abnormal fetuses.
The paper only has a short discussion section where the potential implications or usefulness of the study is outlined. It reads: "...our findings reveal the potential for rat embryonic development in male parabionts, and it may have a profound impact on reproductive biology research."
The advance could generate new solutions to for human fertility issues
Rama / Wikimedia CC 2.0
Scientists have discovered a way to produce eggs from scratch, in mini ovaries grown in tubes, opening up new avenues for the field of reproductive medicine and fertility.
The researchers, led by Katsuhiko Hayashi of Kyushu University, Japan, created of a mouse ovary-like tissue, called an “ovarioid.” They developed the ovarioid with a cocktail of chemicals that induce stem cells to form ovarian-like tissue. This helped them overcome previous limitations, where forming eggs in a lab required fresh ovarian tissue, usually taken from female mice. These results are the very first time that all components, ovary-like tissue and eggs, were made entirely from stem cells.
Hayashi has made other great strides in reproductive biology. In 2011, he and colleagues generated sperm from stem cells, also in mice. Hayashi's group also developed an original method for growing eggs from stem cells with fresh ovary tissue in 2016. The new findings, published in the journal Science in July, could eventually allow people who have damaged or lost ovarian tissue and same-sex couples to potentially have biological children, using their stem cells as the base for generating eggs.
Despite these strides in mice, there currently remains a bottleneck for developing these technologies in humans, as the methods would need to be adapted for developing human eggs. Collecting fresh ovarian tissue from humans also has huge ethical and technical implications, and this idea could circumvent that particular hurdle. But developing human eggs or ovaries from stem cells should be discussed by scientists, policy makers, and ethicists.
Genetic research in fruit flies points to an important link between sleep and cellular housekeeping
hisu lee / Unsplash
How long can a person go without sleep? Sleep deprivation is associated with many impaired body functions, and sleep is required to clear toxins from the brain.
Genetic screens in fruit flies have been used to identify genes regulating many basic cellular and physiological processes, including sleep. A recent study by researchers at the University of Pennsylvania and Howard Hughes Medical Institute found that some sleep genes are involved in managing cellular waste in neurons, a process known as autophagy (or self-eating). Non-functional proteins and other cellular debris are loaded into compartments called autophagosomes to be eventually broken down and reused by the cell. The proteins responsible for this process are known as the autophagosomal proteins.
The study, published in online journal eLife, monitored autophagy in a mutant fruit fly mutant (named argus) that sleeps less than others. They followed the autophagosomes in these flies by tagging them with fluorescent proteins, and found more autophagosomes accumulating in the mutants' neurons. This accumulation means that cellular waste is not being cleared efficiently.
A different mutation in another known autophagy gene, called blue cheese, reduced this autophagosome accumulation. While in argus mutants, autophagosomes do not proceed towards degradation, blue cheese mutants produced fewer autophagosomes to begin with. Interestingly, when neurons don't express blue cheese or other autophagy genes, fruit flies sleep more.
The question remained, does sleep itself also affect the autophagy pathway?
The authors found normal adult flies had more autophagosomes in the early night than in the early morning. Mechanical sleep deprivation of the flies also lead to such an autophagosomal accumulation in neurons. To rule out the possibility of an indirect effect, the authors used a sleep-inducing drug on the flies. They saw that this reduced autophagosome accumulation, emphasizing the relation between sleep and autophagy.
Scientists are closer to a molecular picture of sleep, with a direct link between sleep and a cellular housekeeping pathway. But it's still unclear how this pathway translates into a physiological response. More work in this direction could help researchers find suitable drugs to treat sleep disorders.
Previously, ancient DNA had been extracted from bones, hair, and teeth, but it can also be found in soil
Sequencing of various DNA fragments from skeletal remains has given us a clear understanding of the genetic history of humans. Frequently, ancient DNA (often referred to as aDNA) samples come from recovered bone, teeth, or hair samples. Now, researchers from the University of Vienna have found that cave sediments can preserve ancient DNA well enough to provide genome-length information.
The samples were recovered from the caves of Satsurblia, Georgia where humans lived during the Paleolithic period. The study retrieved samples of three mammalian DNA from a single soil sample. The first genome was of Eurasian ancestry, characteristic of post-ice-age people living in the Near East, North Africa, and parts of Europe. The second was from an unknown extinct species of wolves and dogs, and the last genome was a European Bison.
It’s understood that the DNA remains were preserved in clay-rich sediment from the layers of the cave. The researchers were able to directly sequence DNA found in the sediments, rather than the commonly used method of amplifying small amounts of DNA to make sequencing easier. The small amount of genomic material was sufficient for implementing complementary analyses of various mammalian species to dig some of their population histories. Even from small and fragmentary samples, the scientists were able to determine the human was likely female, carrying XX chromosomes. They were able to even make estimates for percentage Neanderthal mixture into this human sample (approximately 1 percent). The wolf and bison species karyotypes were more mixed, indicating the possible presence of multiple individual wolves and bison samples.
They conclude that this method is an alternative to recovering ancient DNA from the skeletal remains and the team has planned to dive deeper into studying the soil sample of Satsurblia cave to determine the relationship between the effect of climatic changes and ancestral human and animal populations.
Mosquitos carrying Wolbachia pipientis bacteria don't spread dengue fever
Photo by Angga Kurniawan on Unsplash
Mosquitos are the banes of our existence — they suck our blood, they spread disease, and for that, they suck in general. Some viruses that mosquitoes, such as the dengue viruses, can be debilitating or even lethal. Scientists have previously shown that infecting mosquitoes with the insect-specific bacterium, Wolbachia pipientis, can stop or slow the replication of dengue virus within the bugs. That work raised the question: Can Wolbachia-infected mosquitoes help prevent the spread of dengue?
In a new study published in The New England Journal of Medicine, researchers sought to answer this question by releasing Aedes aegypti mosquitoes (the type that transmits dengue) with or without Wolbachia into geographic clusters throughout Yogyakarta, Indonesia. They found that Wolbachia-infected mosquitoes maintained stable populations in their areas of release over the three-year experiment. Importantly, the incidence of dengue fever was significantly lower among people living in clusters with Wolbachia-positive mosquitos relative to control clusters — 2.3 percent and 9.3 percent, respectively.
This study points to the efficacy of Wolbachia-mediated methods for controlling dengue virus, and potentially other diseases like yellow fever and Zika. Given the Wolbachia method is being deployed in various regions throughout the world, this new work bolsters evidence that bacteria may be the key for keeping mosquito-transmitted viruses in check.
Research into other aspects of COVID-19 immunity is swiftly developing
Photo by Jakayla Toney on Unsplash
With vaccination rolling around the world, it might feel for some that life is getting back to normal. But concern around the Delta variant has been growing. It has now been detected in over 130 countries, including 65 in July and early August. Three other variants of concern, Alpha, Beta, and Gamma, are also circulating in the United States.
Recently, a study led by Shane Crotty from La Jolla Institute for Immunology published in Cell Reports Medicine found that T cells that develop as a defense mechanism in people who had recovered from COVID-19 or had received Moderna or Pfizer vaccines remain effective against the Alpha, Beta, and Gamma SARS-CoV-2 variants, along with another variant called CAL.20C. The Johnson & Johnson vaccine had not been available at the time Crotty was doing this research.
“You can think of T cells as a backup system: if the virus gets past the antibodies — if you have vaccine T cells the T cells can probably still stop the variant coronavirus infection before you get pneumonia," said Crotty in Science Daily.
While vaccine development has heavily focused on the antibody response of the body generated by B cells, new variants have mutations in the spike protein that can escape antibody recognition. In April, theoretical research by Binquan Luan and Tien Huynh showed that new mutations can sacrifice a tighter attachment to the human receptor ACE2 to gain antibody evasion abilities.
So far, studies have not converged on whether the Delta variant can cause more severe illness than the original strain in unvaccinated people. However, researchers have verified that two doses of an mRNA vaccine are effective at preventing hospitalization or death, which they report in a recent pre-print. More studies are required to understand vaccine breakthrough infections.
On July 27, WHO highlighted the urgent need to increase COVID-19 vaccination coverage and the recommendation for everyone to use the strategies that have been in place for the past year, including wearing masks in indoor public places.
A jolt of caffeine enhances bees' memories
Caffeine acts as a stimulant, helping wake humans up and keep alert. Caffeine also has a beneficial effect on bumblebees, enhancing their memory.
Bees also like caffeine. Previous studies showed that bees visit caffeinated flowers more often. Researchers from the National Resources Institute and the Horticultural Research at East Malling in the UK decided to find out why caffeine is so alluring. The group tested 86 bumblebees in their experiment. The first group received a caffeinated sugar solution with a strawberry odor. The second group received a sugar solution along with the strawberry odor. The final group just got the sugar solution.
When these bees were let loose, they could choose between landing on flowers with strawberry odors or other flowers. The first two groups associated the sugar solution with strawberry odors, and visited the strawberry flowers more often. Remarkably, caffeine improved the ability of bees to associate the strawberry odor with the sugary reward. They visited strawberry flowers first, more than any other group. The results were published in Current Biology in July.
Farmers usually buy dozens of boxes of bumblebees every year, to help pollinate strawberries. Unfortunately, bees often head over to neighboring wildflowers. Using caffeine could help make agricultural bees more efficient at pollinating strawberries.
Young male Regent honeyeaters are picking up sounds from other bird species
Via Wikimedia
Birds learn songs in two forms: innate, the vocalization that is part of the genetic “package” of the species, and learned. That, like in humans, are the vocalizations learned and influenced by the environment. Only three kinds of birds are known to learn vocalizations this way: hummingbirds, parrots, and passerines (also known as songbirds).
For a bird to learn a vocalization it needs to have a tutor. In healthy populations, tutor availability is high, which increases the chance of young birds to incorporate rare syllables/dialects into their vocal repertoire. But what happens when the population is decreasing, and not many tutors are available?
Research conducted on 146 wild male Regent honeyeaters, an endangered passerine species in Australia and published in the Royal Society showed how the decline of the population affects the vocalization quality of the bird. Because there are few adult male honeyeaters remaining in the wild, young birds are not able to find enough tutors to learn their specific vocalizations. Instead, they are incorporating the vocalizations of other species into their own.
In the future this interspecific vocal learning will create a problem when the birds try to find a mate and reproduce due to the “hybrid vocalizations” not being attractive to the females. To help the species, one of the most important conservation actions is a captive breeding population that aims to boost the population by releasing individuals into the wild. The researchers also evaluated the vocalizations of individuals held in the captive breeding program and found that individuals living in captivity display a shorter and less complex vocalization compared with their wild relatives. These findings may affect the success of the future reintroductions and the fate of the species to avoid extinction.
The results show how the decline of song complexity could reflect the challenges juvenile birds are experiencing in the wild in order to survive. Finally, the research highlights how important it is to consider behavioural aspects in the recovery plan of endangered species.
Researchers tested how "jelly ice cubes" compare for food safety
Vika Wendish / Unsplash
People commonly use ice to keep food cold because of convenience, efficiency, and low cost, but water from melting ice can lead to cross-contamination and germ growth. Also, ice packs contain potentially toxic chemicals, and have a plastic shell that contributes to plastic waste. In a study published in ACS Sustainable Chemistry and Engineering, researchers from UC Davis used gelatin to make jelly ice cubes, plastic free, non toxic, and reusable alternatives to traditional ice cubes that can also reduce cross-contamination.
The jelly ice cubes were most effective at temperatures below zero, because they tend to lose water at higher temperatures. To test whether the jelly ice cubes reduced cross-contamination, the researchers used dye to simulate contaminants, and observed how the dye spread. The jelly ice cubes did not leak any water containing dye, while melted traditional ice was dyed at the end of the test.
While the jelly ice cubes are totally plastic-free, they are unfortunately only partially reusable. The researchers found that although they could be reused for five cycles without physical damage, they lost water and strength over these cycles, reducing their usability. Also, the cubes need to be sanitized with either a water or bleach wash between cycles, which can potentially transfer bleach to food, raising toxicity concerns. These jelly ice cubes are an innovative idea, but their practicality needs to be improved before they can be seriously considered as an alternative to traditional ice cubes or ice packs.
New research uncovers a link between cocaine and acetylcholine that could eventually lead to new treatments for addiction
For decades, neuroscientists have studied how cocaine affects the brain in hopes of developing medications to prevent cocaine addiction. To date, however, none have been approved by the US Food and Drug Administration.
Cocaine is generally thought to produce its rewarding effects by increasing levels of the chemical messengers dopamine and serotonin within the brain. Medications that block these chemical messengers, however, have demonstrated limited efficacy in clinical trials, suggesting that cocaine may affect other chemical messengers as well.
Recently, I and my fellow researchers at Davidson College published study results which suggest that cocaine may target an additional chemical messenger called acetylcholine. In the study, we administered cocaine to small nematode worms often used to study human biology called Caenorhabditis elegans. We observed that cocaine caused the worms to lay eggs. Next, we tested which chemical messengers had to be present in the brain circuit that controls worm egg laying, to make the link between cocaine and egg laying behavior. We found that acetylcholine is necessary for cocaine to cause worm egg laying, suggesting that cocaine might increase acetylcholine signaling.
Additional research in other animals such as rats and mice, and eventually humans, is necessary to find out if cocaine can increase acetylcholine signaling in the brain to cause addiction. If this is the case, however, then neuroscientists may be able to design medications that block acetylcholine to prevent cocaine addiction.
Research in the US Virgin Islands studied turtle habitat use and partitioning
Photo by Kris Mikael Krister on Unsplash
Sea turtles are popular marine species, yet there is still a lot we don't understand about where in the ocean different types of sea turtles live and what resources they need. Sea turtles maintain diverse ecosystems by feeding on coral competitors such as sponges and algae. They also support tourism and local economies. Despite their impact, all six sea turtle species found in US waters are listed as threatened or endangered under the Endangered Species Act.
A new study published in Marine Biology explores the habitat use of young Hawksbill sea turtles in the US Virgin Islands, which affects their ability to survive and reproduce.
Twenty-three juvenile Hawksbill turtles within Brewers Bay and Hawksbill Cove, southwest of the island of St. Thomas, were tagged with transmitters on their shells during a three-year study period from February 2015 to February 2018. Such long study periods are common with larger marine species to gather a sufficient sample size. Up to 41 acoustic receivers throughout Brewers Bay and Hawksbill Cove collected data during both the day and at night on the turtles’ depths and locations, which the researchers analyzed to understand what types of habitats they used.
They found that the sea turtles used specific regions of Brewers Bay and Hawksbill Cove and explored more locations and depths during the day than at night. They frequented more habitats such as coral, sand, and concrete structures during the day, and mostly selected coral reefs at night. However, there was little overlap between individual sea turtles, indicating that they do divide resources among themselves. The results will help improve the preservation of this important but jeopardized species.
It might be useful to set some reminders for things you intend to do later in the day
Photo by Somnox Sleep on Unsplash
Remembering to do something in the future is called prospective memory. For example, you might decide on the drive to work in the morning that you want to watch the latest episode of your favorite show when you get home at night. In doing so, you are setting an intention (“I want to watch the show”) and its context (“-when I get home tonight”). Prospective memory consists of two components, a retroactive and prospective component. The retroactive component is remembering what you need to do when the time comes, and the prospective component is simply remembering to do that thing when the time comes.
In a recent publication in the journal Memory & Cognition, three researchers from Heinrich-Heine-Universität Düsseldorf set out to study how sleep can help us remember what we need to do in the future. In their study, participants were asked to perform a prospective memory task, by pressing a key when shown a word they had learned a few hours ago. Half of the participants learned the words in the morning and were tested at night, while the other half learned the words at night, and were tested the next morning. The researchers hypothesized that the participants who were tested on the morning of the next day would be better at remembering to press the key on the correct word.
They found that participants did perform better when tested in the morning, but this was not strictly due to sleep. Both groups had actually performed the best when tested in the morning, and the researchers suggest that this effect was due to our attention being refreshed in the morning. Taken together, their findings demonstrate that we are better at remembering to do things in the morning, not because sleep helps us store memories, but because we are more refreshed after a good rest. Translated into practical advice, since our prospective memories are best in the morning, it might be useful to set some reminders for things you intend to do later in the day.
These recommendations will help improve the safety and access of genome-editing treatments
The NIH Image Gallery.
Last month, the World Health Organization (WHO) released new guidelines in a global effort to regulate genome editing technology. The 18-member committee was formed at the end of 2018 in the aftermath of He Jianku’s experiments resulting in the birth of twin girls with edited genomes. In accordance with their 2019 statement, the committee continues to advise against these experiments which would birth other gene-edited babies. WHO published the guidelines alongside a governance framework document to, "provide advice and recommendations on appropriate institutional, national, regional and global governance mechanisms for human genome editing."
The WHO report outlines important recommendations as our technology continues to rapidly improve. Consistent regulation would help dissuade unregulated genome-editing treatment facilities from popping up. The committee also explored ways to improve access to genome-editing treatments through ethical licensing mechanisms.
Finally, the report calls for an expanded registry to monitor human genome-editing clinical trials. Additionally, it would establish a mechanism that allows whistleblowers to report unethical or dangerous experiments. Moving forward, these recommendations will help improve the safety and access of genome-editing treatments.
Adoptive cell therapies for cancer require the production of lots of T cells, so finding the right substrate is key
Kim Hasenkrug, Dave Dorward, Austin Athman on Wikimedia Commons (CC BY SA 4.0)
T cells are immune cells in our bodies that find and attack infected cells. Researchers are also engineering T cells to fight hard-to-target diseases like cancer. In adoptive cell therapies, T cells are trained against cancer markers. Successful therapies requires lots of T cells, which are multiplied many times outside of a person's body. However, currently this T cell expansion step takes several weeks. Figuring out how to grow T cells quickly in the lab is an important area of research.
One critical environmental variable is the stiffness of the cells’ underlying substrate, which is the surface on which they are grown. Previously, some reports claimed that cell growth increased with stiffness, while others argued that the cells grow optimally on softer substrates. In a new study published in the journal Biomaterials, researchers from Columbia University sought to more definitively understand how substrate stiffness impacts T cell activation and growth.
Their findings reconciled the long-standing scientific discrepancy. They discovered that T cells exhibited a two-phased response to changing substrate stiffness. Initially, both T cell proliferation, measured by the rate of cell division, and T cell activation increased with stiffness. But after a certain critical stiffness, these measures began to decrease. In other words, there is a "peak substrate stiffness" for growing T cells.
This work is primarily of importance to the design of future biomaterials for growing T cell populations for use in cancer-fighting adoptive cell therapies. Hopefully, these findings will make these therapies more accessible by reducing their timescale from weeks to days.
A new study summarizes the challenges that older adults face in getting the health care they need
About one in six Americans is 65 years and older and this statistic is expected to be almost one in four by the year 2050. Age might be just a number; however, aging is an inevitable reality, and one the American healthcare system has not yet embraced.
Older adults in America make up only 15 percent of the population, but account for almost 50 percent of healthcare costs. Compared to other age groups, they are three times more likely to be hospitalized. These rates are projected to increase, yet the needs, values and preferences of this population are often ignored.
In an effort to explore the experiences, preferences, and expectations of this underserved group in health care, a group of researchers from three US universities conducted a study involving older adults and their caregivers in Michigan. This study used focus group sessions to facilitate open, in-depth discussions among 36 participants, a group of diverse individuals with respect to age, gender, race, and backgrounds. Separate sessions were conducted for the 18 older adults and their caregivers, who play an integral role in health care.
The researchers identified and analyzed themes from the focus group sessions. Their discussions highlighted that older adults require specialized health needs but, their needs are neither prioritized nor met. Instead, they are treated with disrespect, apathy, and indignity. Older adults also emphasized that they need providers skilled at diagnosing their illnesses (which may present differently than the same sickness in a younger person), and caregivers described bad experiences trying to coordinate their loved ones' care across doctors. This research highlights the need for trained, specialist providers as geriatricians and social workers who can offer an integrated, holistic approach to caring for older adults.
The sun shines hottest on pockets of glacier that don't reflect away its rays
Kertu Liis Krigul / Wikimedia
Have you ever noticed a snow-covered street dimpled with little holes on the surface? Called cryoconite holes, they are small circles of black dust, soot, or dark microbes that form on blankets of snow. The dark patches absorb more sunlight than the nearby white snow, warming and melting holes beneath itself. These holes can be tiny unique ecosystems for arctic life. They may also impact glacier loss.
The glaciers of Kashmir are melting at frightening rates. A new study is the first to examine how that melt relates to cryoconite holes. Scientists examined Machoi glacier, a special region that has been photographed since 1875 due to its beauty. These historic photos combine with satellite imagery to reveal that the ice sheet has been receding for the last 100 years.
Scientists revealed that cryoconite holes lead to a loss of albedo, or reflection of sunlight. This then causes an increase in temperature at certain points that exacerbate glacier melting. The study also determined that that during the COVID-19 lockdowns, aerosol pollution levels drastically decreased on the glacier. Those same pollutants, when they land in snow, may act as sites where cryoconite holes begin to form, though the science of that process is still developing. Thus, air pollution from traffic and industrial plants may increase cryoconite holes formation, which further melts our glaciers. The study urges future researchers to pay more attention to cryoconite holes and reveal their effects on glacier biogeochemistry.
This technique is a game-changer to study early human development and to understand how babies are made
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Early human development is an incredibly complex and well-orchestrated process. Researchers have been trying to understand the mechanisms involved in transitioning from a ball of undifferentiated cells with particular specialty into organized functional tissues. Understanding these mechanisms is fundamental to advancing human embryology and the study of human health.
To this purpose, researchers have relied on animal embryos, primarily from mice, or discarded human embryos from in vitro fertilization (IVF) treatments. Yet, animal embryos do not fully represent human biology, and human embryos are scarce and using them brings on ethical concerns. To bypass these problems, stem cell biologists have developed human embryo models in vitro.
The human blastocyst is the structure formed from the fertilized egg at around day 6 of development. The blastocyst divides into three structures: the trophoblast, the epiblast, and the hypoblast. All the cells that eventually form every tissue in the human body arise from the epiblast. (The trophoblast and the hypoblast will form the tissue outside an embryo that interacts with maternal tissue.)
Researchers from the Living Systems Institute at the University of Exeter, UK, were able to mimic these first stages of human development by growing stem cells. The cells self-organized and specialized similarly to the three-structure blastocyst. These lab-grown models are called blastoids because of their resemblance to the human blastocyst in structure and gene expression profile.
This was not the first time researchers have formed blastoids; two other teams previously established the first-ever human in vitro blastoids. However, their models were difficult to grow; since they reported only around 20 percent of blastoid formation. In contrast, researchers in this study developed a more reliable and efficient protocol, reaching about 80 percent of blastoid formation.
More optimizations will be needed to fully recapitulate the behavior of human blastocysts. Nevertheless, reliably producing in vitro blastoids on demand provides an alternative for researchers to study early human embryogenesis. These models will allow to improve IVF treatments and to better understand infertility and developmental disorders.
The story behind these numbers is complex, but opioids have played a major role
Jeff Anderson on Flickr
On Wednesday July 14, the Centers for Disease Control and Prevention released new data on the incidence of drug overdoses in the US. According to the provisional figures, the number of overdose deaths in 2020 jumped nearly 30 percent above 2019 levels to 93,331 — the largest year-over-year increase on record.
The story behind these numbers is complex, but opioids have played a major role. Opioid overdose deaths first started rising in the late 1990s due to increased prescribing of prescription opioids. The second wave began in 2010, with a rapid increase in overdose deaths involving heroin. Most recently, the introduction of the synthetic opioid fentanyl in 2013 ushered in the third wave of the opioid epidemic. The drug is 50 to 100 times more potent than morphine, so just a few hundred micrograms can cause an overdose.
Adding to the danger, fentanyl is often found in combination with other drugs such as cocaine. The proportion of overdose deaths involving fentanyl and other opioids increased between 2019 and 2020 in part due to the insidious practice by people manufacturing the drugs of mixing small but potentially lethal amounts of fentanyl with other drugs without the knowledge of the person who uses it.
Although shocking in its magnitude, the increase in overdose deaths didn’t come as a surprise to healthcare officials. Limitations on social mobility due to COVID-19 had the effect of reducing access to social support networks and harm-reduction initiatives, such as narcan administration, that are key to combating drug overdose.
The 2020 data on drug overdoses is concerning, but there may be hope that the situation can be meaningfully improved in the short term. Since COVID-19 eroded the support systems that prevent drug overdose, the pandemic’s end should enable those systems to be repaired, allowing us to combat two public health crises at once. Even if overdose death rates can be reversed in the short term, however, it will take a concerted effort by governments and communities to reverse the underlying trends of the overdose epidemic.
More than a mere delicacy, the humble lobster could teach us a lot about healthy aging
Jeremy Zero on Unsplash
The American lobster – easily recognizable by its two hefty claws – can reach the impressive age of 100 years. The remarkable longevity is accompanied by very few signs of aging; it continuously grows and reproduces throughout its life and does not suffer from age-related diseases such as cancer. This exceptional resilience has garnered interest from researchers that are curious to decipher the reasons behind the lobster’s longevity and good health.
Could the genome of the American lobster provide clues about their healthy aging? Researchers at the Gloucester Marine Genomics Institute have recently published the first draft of the American lobster genome, which revealed surprising, first insights into the animal’s unique resilience mechanisms.
The researchers found genes encoding for a novel class of proteins that combine both neuronal and immune-related functions. By coupling the neural and immune system, the lobster could fight off pathogens more efficiently.
The researchers also surveyed the lobster genome for genes involved in safeguarding the genome. These safeguards prevent genomic alterations and mutations, which is crucial for longevity and warding off cancer. The researchers found that the American lobster has an extended repertoire of genes encoding for proteins that silence certain regions of the genome. These regions need to be silenced to prevent potentially disease-causing mutations such as chromosomal rearrangements. By ensuring that these regions remain silenced, the American lobster safeguards its genome throughout its long life.
With the newly deciphered lobster genome as a starting point, future research will provide further insight into the healthy aging strategies of the American lobster. More than a mere delicacy, the humble lobster could teach us a lot about healthy aging.
A new research paper demonstrates how science and philosophy exist on a continuum
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Earlier this year MC Hammer (yes, the MC Hammer) rebuked a Twitter user for claiming that science and philosophy were fundamentally opposed. Instead, he reminded us, science and philosophy can work together. And now a paper forthcoming in the British Journal for the Philosophy of Science provides further evidence in favor of MC Hammer’s claims.
The researchers identified a substantial body of work by philosophers of science that used “philosophical tools to address scientific problems and provide scientifically useful proposals.” They call such work philosophy in science. So what kind of tools do philosophers use that can be applied to science? The study authors don’t offer an exhaustive list, but point to activities such as making distinctions and proposing definitions, critiquing scientific methods, and combining multiple scientific fields as examples of typical philosophical tools. And while scientists use these methods too, they don’t tend to do so as often or as rigorously as philosophers.
As an example, one philosophy in science paper referenced by the researchers is by philosophers Peter Heywood and Michael Redhead, published in Foundations of Physics in 1983. They prove that certain natural assumptions about the world are not compatible with quantum mechanics and, as Heywood and Redhead explicitly note, “an essential part” of their demonstration involves distinguishing between two different forms of an important concept in quantum mechanics that were often confused. So Heywood and Redhead address a scientific problem (are certain natural assumptions compatible with quantum mechanics?), use philosophical tools (making distinctions and proposing definitions) and provide a scientifically useful proposal (a proof).
The researchers suggest that, far from being fundamentally opposed disciplines, science and philosophy belong on a continuum. And when scientists and philosophers work together to combine their tools, they can make both scientific and philosophical advances. In the words of MC Hammer “It’s not science vs Philosophy ... It’s Science + Philosophy.”
Medication abortion has been around for 20 years, and is a safe alternative to surgical abortion for many pregnant people
Tbel Abuseridze on Unsplash
Medication abortion has been around for 20 years, and is a safe alternative to surgical abortion for many pregnant people. However, despite their relative safety, the U.S. Food and Drug Administration (FDA) has very strict requirements about how and where these pills are accessed; many states also require that the first of the pills, mifepristone, be swallowed in the physical presence of the prescribing clinician. The FDA also mandates that only clinics - and not pharmacists - dispense mifepristone.
Critics of these regulations allege that they create unnecessary barriers to safe abortion, particularly for people in rural areas, people with disabilities and other people who might have trouble getting to a clinic. They point out that riskier medications are routinely dispensed in pharmacies. The regulations’ supporters cite safety concerns around pharmacists filling prescriptions for mifepristone, though many clinicians, and the American College of Obstetrics and Gynecology support treating it like other drugs.
A new study obtained special permission for clinicians at eight trial sites to provide eligible patients with a prescription for mifepristone (and the second medication, misoprostol), which they would then fill at a partnering pharmacy. Patients completed surveys about their experiences two days and two weeks after their abortion.
Over 91 percent of study participants reported that they were somewhat or very satisfied with their pharmacy experience, and, of those who had had previous medication abortions, 81 percent said that getting their medications from the pharmacy was the same or better than getting them from the clinic. Two weeks later, 62 percent of participants said that they would prefer to have abortion medications called into the pharmacy, and 28 percent said that they would be fine with obtaining them at either the pharmacy or clinic. Some participants expressed that the pharmacy gave them more control over their abortion experience, because it let them start the process on their own schedule, rather than the clinic’s.
Overall, this study supports the case for loosening the regulations around medication abortion access, and specifically allowing abortion medication drugs to be dispensed by pharmacists. The FDA recently announced that their plans to reconsider their regulations on mifepristone.
Rock varnish is produced by magnesium-rich bacteria
Rock varnish is a dark stain primarily found on rocks in desert environments, a smooth coating that provides a perfect canvas for rock carvings, or petroglyphs. How these stains got there, however, is a long-standing scientific mystery written about in the 1800s by both Charles Darwin and Alexander von Humboldt, and still debated to this day.
Since rock varnish is primarily found on surfaces with high sun exposure that also tend to have trickling water or dew accumulation, light and water are known to be important for the formation process. However, while most of the material in varnish comes from airborne dust and weathered rocks, this thin coating also has an extremely high concentration of manganese compared to the surrounding environment, and scientists haven’t been able to explain where that extra metal comes from.
Until now. Using the Stanford Synchrotron Radiation Lightsource, scientists were recently able to map the different compounds in rock varnish, finding that the high concentration of manganese in continuous layers must be related to ongoing biological processes as opposed to a long-term chemical reactions on the rock surface due to sun exposure. Genomic sequencing of the stain material also revealed an abundance of Chroococcidiopsis bacteria, which produce extra manganese to protect against harsh solar radiation, effectively creating a natural sunscreen for themselves. That extra metal is left behind when the cells die and then oxidized to form the dark, smooth surface.
This research concludes that rock varnish is a byproduct of magnesium-rich bacteria over millennia, linking the thin, dark stain to the existence of life. And if they’re right, that life might not be limited to our own planet — the Curiosity rover has found rock varnish on Mars. We haven’t seen any petroglyphs on the red planet just yet, but scientists are only beginning to scratch the (metaphorical) surface of what the existence of rock varnish on Mars means in the search for extraterrestrial life.
The disease is a severe threat to the Caribbean's vibrant coral reefs
G. Mannaerts on Wikimedia Commons (CC BY SA 4.0)
The nature of transmission of the most recent deadly coral disease in the Caribbean has been a mystery since it spread beyond its origin on Florida reefs. Newly-published evidence suggests container ships may be to blame.
Stony coral tissue loss disease (SCTLD) first appeared in Florida in 2014. By 2019, the disease had spread across the Florida Keys, destroying reefs along the way. It had also reached other areas in the Caribbean, such as the US Virgin Islands, without touching the islands of the Bahamas, which are physically closer to Florida. It eventually did reach the Bahamas, but not until the end of 2019. Because of this leapfrogging and backtracking nature of transmission, scientists determined that the disease was being transported via ballast water in container ships, according to a studypublished in Frontiers in Marine Science in July.
Additional evidence from the pattern of disease spread shows that reefs closer to ports had higher mortality rates than those farther away, also supporting the ship transmission hypothesis. Once present on an island, the disease spreads rapidly from coral to coral through close contact and water currents.
SCTLD is a severe threat to Caribbean coral reefs, given that it is waterborne, highly transmissible, and affects over 20 species of coral. Its dramatic presentation makes it seem even more alarming, as the live tissue of a coral appears to melt off its skeleton. The more information scientists have about how it spreads increases the chances that managers and activists can stop its devastation.