Cholesterol may not be the only lipid involved in trans fat-driven cardiovascular disease Excess cholesterol is known to form artery-clogging plaques that can lead to stroke, arterial disease, heart attack, and more, making it the focus of many heart health campaigns. Fortunately, this attention to cholesterol has prompted the development of cholesterol-lowering drugs called statins and lifestyle interventions like dietary and exercise regimens. But what if there's more to the picture than just cholesterol? New research from Salk Institute scientists describes how another class of lipids, called sphingolipids, contributes to arterial plaques and atherosclerotic cardiovascular disease (ASCVD). Using a longitudinal study of mice fed high-fat diets—with no additional cholesterol—the team tracked how these fats flow through the body and found the progression of ASCVD induced by high trans fats was fueled by the incorporation of trans fats into ceramides and other sphingolipids. Knowing that sphingolipids promote atherosclerotic plaque formation reveals another side of cardiovascular disease in addition to cholesterol.
The findings, published in Cell Metabolism, open an entirely new avenue of potential drug targets to address these diseases and adverse health events like stroke or heart attacks.
When dietary fats enter the body through the foods we eat, they must be sorted and processed into compounds called lipids, such as triglycerides, phospholipids, cholesterol, or sphingolipids. Lipoproteins—like the familiar HDL, LDL, and VLDL—are used to transport these lipids through the blood.
Sphingolipids have become useful biomarkers for diseases like ASCVD, non-alcoholic fatty liver disease, obesity, diabetes, peripheral neuropathy, and neurodegeneration. However, it is unclear exactly how the incorporation of different dietary fats into sphingolipids leads to the development of ASCVD.
The fate of dietary fat is often determined by the protein that metabolizes it.
The team suspected that trans fats were being incorporated into sphingolipids by SPT, which, in turn, would promote the excess lipoprotein secretion into the bloodstream that causes ASCVD.
To test their theory, they compared the processing of two different fats, cis fats and trans fats. The difference between these two comes down to the placement of a hydrogen atom; cis fats, found in natural foods like fish or walnuts, have a kink in their structure caused by two side-by-side hydrogen atoms, whereas trans fats, found in processed foods like margarine or anything fried, have a straight-chain structure caused by two opposing hydrogen atoms. Importantly, the kink in cis fats means they cannot be tightly packed—a positive feature for avoiding impenetrable clogs.
The researchers combined mouse modeldietary manipulation with metabolic tracing, pharmacological interventions, and physiological analyses to answer their question—what is the link between trans fats, sphingolipids, and ASCVD?
The researchers found the incorporation of trans fats through SPT increased lipoprotein secretion from the liver, which then promoted the formation of atherosclerotic plaques. In the end, they saw mice consuming a high trans fat diet were producing trans fat-derived sphingolipids that promoted the secretion of VLDL from the liver into the bloodstream. This, in turn, accelerated the buildup of atherosclerotic plaques and the development of fatty livers and insulin dysregulation. High cis-fat diet mice, on the other hand, experienced shorter-term, less harmful effects like weight gain.
Jivani M. Gengatharan et al, Altered sphingolipid biosynthetic flux and lipoprotein trafficking contribute to trans-fat-induced atherosclerosis, Cell Metabolism (2024). DOI: 10.1016/j.cmet.2024.10.016
Scientists Put Cats in Microgravity to See What Would Happen
There is, perhaps, no animal on this planet as lithe as the simple domestic cat. And not least in their bag of acrobatic tricks is one for which they are well-known: the ability to land, safely, on their velvet paws, when subjected to a tumble.
In the 1950s, humans discovered parabolic flight: the ability to simulate zero-G conditions using specially-designed aircraft plummeting along a precise flight trajectory. And with that came a devilish thought. What would happen to a cat's ability to land on its feet if they can't tell the difference between up and down? So, this is what the bright minds at the US Air Force Aerospace Medical Research Lab decided to find out.
Parabolic flight is not true microgravity, but a brief experience of its effect. Just as a rapid descent in an elevator can make you feel lighter in your loafers, passengers on an aircraft will experience weightlessness while rapidly descending from a high altitude to a lower one. It's pretty disorienting, earning parabolic flight the nickname 'vomit comet' for good reason.
The first experiments were conducted on board a Convair C-131 Samaritan, and yes, there is absolutely video of the proceedings. A similar experiment involved releasing pigeons inside the C-131 during parabolic flight.
It's fascinating to watch. The narration for the video says the cats' "automatic reflex action is almost completely lost under weightlessness". Almost – but not quite. Although the cats seem disoriented, they are still able to twist and turn their bodies around as they try to figure out where they are going to fall. Part 2
Blood vessel-like coating could make medical devices safer for patients
Researchers have developed a coating that could make medical devices safer for millions of patients, reducing the risks associated with blood clots and dangerous bleeding. The work has been published in Nature Materials.
The new material, designed to mimic the natural behavior of blood vessels, could allow for safer use of blood-contacting devices like catheters, stents, blood-oxygenation machines and dialysis machines—especially in cases where blood clots are a significant concern.
This discovery could be a transformative step in the development of safer medical devices. By designing a coating that mimics the body's natural approach to preventing clots, researchers have created a solution that could dramatically reduce the need for risky blood thinners before and after patients use these devices.
Thrombosis, or clot formation, is a major challenge when blood-contacting devices are used. Unlike natural blood vessels, these devices can trigger clotting by activating specific proteins in the blood. Blood clots can obstruct the device, disrupting treatment, or lead to severe complications such as stroke and heart attack.
Doctors often prescribe high doses of blood thinners to prevent clots on these devices, but this approach increases the risk of dangerous bleeding—a trade-off that many patients and clinicians would rather avoid.
The newly developed coating offers a promising alternative. It's engineered to imitate how blood vessels function—encouraging normal blood flow without triggering clot formation. Imagine the coating as a "soft barrier" on a device that attracts a key blood protein but keeps it from activating the clotting process.
By interacting with this protein in a controlled way, the coating prevents it from sparking a cascade of events that lead to clot formation.
In lab and animal studies, the coating demonstrated significant reductions inclot formationon device surfaces, without the use of blood thinners and without affecting the normal clotting functions elsewhere in the body.
One of the most surprising insights was that controlling the interaction between the coating and specific blood proteins could prevent clotting without disrupting the body's natural balance. This shows us that mimicking the body's own mechanisms, rather than simply repelling blood components, is key to truly biocompatible device design.
The innovation comes as demand for blood-contacting devices continues to rise.
Additionally, the team is interested in understanding whether this approach could eventually be adapted to address other blood-related complications, such as inflammation or infection, in long-term medical implants.
Antithrombotic coating with sheltered positive charges prevents contact activation by controlling factor XII–biointerface binding, Nature Materials (2024). DOI: 10.1038/s41563-024-02046-0
'Moonlighting' enzymes may lead to new cancer therapies
Researchers at the Center for Genomic Regulation (CRG) reveal that metabolic enzymes known for their roles in energy production and nucleotide synthesis are taking on unexpected "second jobs" within the nucleus, orchestrating critical functions like cell division and DNA repair.
The discovery, reported in two separate research papers in Nature Communications, not only challenges longstanding biological paradigms in cellular biology but also opens new avenues for cancer therapies, particularly against aggressive tumors like triple-negative breast cancer (TNBC).
For decades, biology textbooks have neatly compartmentalized cellular functions. Mitochondria are the powerhouses of the cell, the cytoplasm is a bustling factory floor for protein synthesis, and the nucleus a custodian of genetic information. However, scientists have now discovered that the boundaries between these cellular compartments are less defined than previously thought.
Metabolic enzymes are moonlighting outside of their traditional neighborhood. There's an overlap in the skillset, but they're doing entirely different jobs for entirely different purposes. Surprisingly, their secondary roles in the nucleus are just as critical as their primary metabolic functions.
In one of the studies, researchers focused on the metabolic enzyme MTHFD2. Traditionally, MTHFD2 is found in the mitochondria, where it plays a key role in synthesizing the building blocks of life and contributing to cell growth. Others research work reveals that MTHFD2 also moonlights within the nucleus, where it plays a pivotal role in ensuring proper cell division.
The study is the first to demonstrate that the nucleus relies on metabolic pathways to maintain the integrity and stability of the human genome. The nucleus isn't just a passive storage space for DNA; it has its own metabolic needs and processes.
In the second study, researchers turned their attention to triple-negative breast cancer, the most aggressive type of breast cancer there is. The disease is responsible for around one in eight breast cancer diagnoses and amounts to roughly 200,000 new cases each year worldwide.
Usually, excessive DNA damage triggers cell death. However, TNBC has a propensity to accumulate DNA damage without consequence, making it resilient to conventional treatments. The study helps partly explain why: the metabolic enzyme IMPDH2 relocates to the nucleus of TNBC cells to assist in DNA repair processes.
IMPDH2 acts like a mechanic in the cell's nucleus, controlling the DNA damage response that would otherwise kill the cancer cell. By experimentally manipulating IMPDH2 levels, the team found they could tip the balance. Increasing IMPDH2 within the nucleus overwhelmed the cancer cells' repair machinery, causing cells to self-destruct.
It's like overloading a sinking ship with more water—eventually, it sinks faster. Their approach effectively forces TNBC cells to succumb to the very DNA damage they are typically resilient to. The study can also lead to new ways of monitoring cancer. The research on IMPDH2 also studied its interaction with PARP1, a protein already targeted by existing cancer drugs. IMPDH2 could serve as a biomarker to predict which tumors will respond to PARP1 inhibitors. Both studies contribute to an emerging field of therapies targeting cancer by exploiting its metabolic vulnerabilities.
Nuclear localization of MTHFD2 is required for correct mitosis progression,Nature Communications(2024).DOI: 10.1038/s41467-024-51847-z
Nuclear IMPDH2 controls the DNA damage response by modulating PARP1 activity,Nature Communications(2024).DOI: 10.1038/s41467-024-53877-z
DNA packaging directly affects how fast DNA is copied in cells, scientists discover
Researchers have found that the way DNA is packaged in cells can directly impact how fast DNA itself is copied during cell division. They discovered that DNA packaging sends signals through an unusual pathway, affecting the cell's ability to divide and grow.
This opens up new doors to study how the copying of the DNA and its packaging are linked. These findings, published in Molecular Cell, may help scientists to find therapies and medicines for diseases such as cancer in the future.
Every day, our cells divide. Each time they need to copy both their DNA and the structure in which the DNA is packed. This packaging, called chromatin, acts as a guide. It tells the cell how, where and when to 'read' and use the information in the DNA. It is important that both the DNA and its chromatin are copied accurately to ensure young and healthy cells. Problems with this process are often seen in diseases like cancer.
The copying of chromatin has a direct effect on the mechanisms that copy DNA itself. If there is a problem with DNA packaging, the cell quickly senses this issue. But instead of triggering a typical stress response, the cell responds by slowing down its cycle of growth and division, without stopping it completely. The slower cycle still allows the cell to divide, but the new cells often struggle to continue to grow, preventing them from dividing again.
So, these mechanisms, which copy DNA and its packaging, are closely connected to cell growth. This discovery paves the way for new studies on these pathways and how DNA packaging can control cell growth. In the future, this knowledge could help to find new treatments for diseases like cancer.
'Drowning' and 'dying' mangrove forests in Maldives signal global coastal threat, say researchers
Researchers have found evidence that mangrove forests—which protect tropical and subtropical coastlines—are drowning in the Maldives.
Their findings,published12 November inScientific Reports,
The research team, led by Northumbria University, warn that the findings have implications not only for the Maldives, but also for other island nations and coastal ecosystems around the world.
In 2020, more than a quarter of the Maldivian islands containing mangrove forestssaw their trees experiencing a gradual deterioration before dying, a condition known as dieback.
In 2020, more than a quarter of the Maldivian islands containing mangrove forests saw their trees experiencing a gradual deterioration before dying, a condition known as dieback. Satellite imagery of both inhabited and uninhabited islands revealed the severity of this issue, showing that some islands lost over half of their mangrove cover.
Mangroves play an essential role in protecting coastal regions by acting as natural barriers against storms, erosion and flooding. As biodiversity hotspots, they are vital nurseries for marine species such as crabs, prawns and fish making them crucial for food security and livelihoods in many coastal communities. They also provide valuable resources such as construction materials for housing.
Researchers combined evidence from sea level, climate data and remote sensing with field observations of sediment geochemistry and dendrology to investigate the mangrove dieback.
Their analysis of mangrove wood revealed that the dead trees showed greater signs of salinity stress compared to living trees.
This stress indicates that the roots of the trees were struggling to cope with increased salt levels, which was a key factor in their eventual death. The researchers found that sea levels around the Maldives rose at an accelerated rate of over 30mm per year between 2017 to 2020. Towards the end of this period, an unusually intense climate phenomenon known as the Indian Ocean Dipole occurred. This caused warmer sea surface temperatures and an increase in sea level in the Western Indian Ocean.
Although mangroves naturally build up their own sediment, allowing them to adapt to gradually rising seas, this rate of sea level rise was too fast for the mangroves to keep pace.
As tidal movements are more limited in the basin areas where many mangrove forests grow, the rising sea level meant that seawater effectively flooded the forests. This lack of tidal movement and flooding prevented the mangroves from building the sediment they needed to stay above water. They eventually lost their resilience and died off by drowning. As the mangroves' build-up of sediment slowed down due to the pace of the rising sea level, the soil salinity increased beyond what even these salt-tolerant trees could handle. Essentially, the mangroves were drowning.
The extreme magnitude of dieback seen in the Maldives is a vivid illustration of how climate change may push natural systems past their limits, with cascading consequences for both nature and people.
Carruthers, L. et al. Sea-level rise and extreme Indian Ocean Dipole explain mangrove dieback in the Maldives, Scientific Reports (2024). DOI: 10.1038/s41598-024-73776-z
At a time when synthetic plastic has polluted nearly every corner of the globe and appeared in food and in the human body, researchers have developed a new plastic that dissolves in water.
The kind of impact that human-made materials are making on the living world is resulting in climate change, pollution and more. One of the ways that we are able to address this is to make materials sustainable and also make materials which are smart or intelligent.
This new bioplastic MECHS—an acronym for Mechanical Engineered Living Materials with Compostability, Healability and Scalability is one such effort.
The researchers presented their discovery in a paperpublishedin the journalNature Communications.
The study showcases the researchers' most recent work with engineered living materials, which use living cells to produce functional materials.
First, the nature-inspired solutions can be made to regenerate, regulate and/or respond to external stimuli such as light and can even heal itself.
Secondly, unlike the plastics that are polluting the planet and our bodies, the materials are biodegradable in water and even the compost bin.
But while engineered living materials have been manipulated to adhere, catalyze and remediate, and be either soft or stiff, such materials have not been scalable for widespread production.
That's where MECHS comes in.
MECHS consists of engineered E. coli bacteria with a fiber matrix to create a paper- or film-like material.
The fibers give MECHS several desirable properties. It means that MECHS can stretch like plastic wrap, can be genetically engineered by adding proteins or peptides to make it more or less stiff. And it is healable—a small amount of water disentangles the fibers, which then re-entangle as the MECHS dries.
Meanwhile, a lot of water or a trip to a compost bin causes the material to dissolve. In fact, it dissolves much faster than other biodegradable plastics, the researchers found.
Finally, the material can also be easily mass produced in a process similar to paper manufacturing.
Avinash Manjula-Basavanna et al, Mechanically Tunable, Compostable, Healable and Scalable Engineered Living Materials, Nature Communications (2024). DOI: 10.1038/s41467-024-53052-4
Young coral use metabolic tricks to resist bleaching, research reveals
Coral larvae reduce their metabolism and increase nitrogen uptake to resist bleaching at high temperatures, according to a study published November 12 in the open-access journal PLOS Biology.
High ocean temperatures cause coral bleaching, which results from the disruption of the relationship between corals and their symbiotic algae, an increasing concern as global temperatures rise. However, relatively little research has examined the effects of high temperatures during the early life stages of corals.
In this study, researchers exposed coral larvae to high temperatures at the Hawai'i Institute of Marine Biology. For three days during their first week of development, the larvae and their algal symbionts were treated to temperatures 2.5 degrees Celsius above ambient temperature, similar to expected changes in seawater due to climate change.
The coral larvae showed no signs of bleaching in the heated water, and they were able to maintain rates of algal photosynthesis and the supply of carbon-based nutrition from the algae to the host. However, there was a 19% reduction in coral metabolism, as well as increased uptake and storage of nitrogen by the coral, both of which are apparent strategies that improve coral survival.
Reduced metabolism allows the coral to conserve energy and resources, also seen in adult corals during bleaching. The change in nitrogen cycling seems to be an adaptation by the coral to limit the amount of nitrogen available to the algae, thus preventing algal overgrowth and the destabilization of the coral-algae relationship. It remains unclear how effective these strategies are at higher temperatures and for longer durations. Further research into the details and limitations of coral reaction to high temperatures will provide crucial knowledge for predicting coral response and protecting coral reefs as global temperatures continue to rise.
The authors add, "This research reveals that coral larvae must invest in their nutritional partnership with algae to withstand stress, offering key insights into strategies to avoid bleaching in earliest life stages of corals."
Huffmyer AS, et al. Coral larvae increase nitrogen assimilation to stabilize algal symbiosis and combat bleaching under increased temperature, PLOS Biology (2024). DOI: 10.1371/journal.pbio.3002875
Study challenges popular belief that children are quicker at picking up new motor skills than adults
Contrary to popular belief, children aren't better at learning new skills than adults. Indeed, young adults seem to learn faster than kids—but also tend to forget more quickly. Here, better sleep seems to advantage children. This is the conclusion of a new study.
It's widely believed that children learn newmotor skillsfaster than adults, whether it's mastering slopes or skateparks, learning new languages, doing cartwheels or picking up new dance moves from TikTok.
"There's an assumption in popular science literature and various textbooks that children in a certain age range—from roughly the age of 8 until puberty—are better at learning new skills than adults. This is often described as a 'golden age for motor skills learning.'But there's no actual physiological basis for this so-called golden age.
The popular notion of a pre-pubescent motor learning peak prompted the researchers to investigate how age-related differences in our central nervous system affect motor skill learning. Their findings are nowpublishedinDevelopmental Science.
In the study, the researchers tested the motor learning abilities of 132 participants from four age groups: 8–10 years, 12–14 years, 16–18 years, and 20–30 years. In a lab setting, participants practiced moving a cursor on a computer screen with fast and precise finger movements.
Participant performance was measured immediately after being introduced to the task (as a baseline), during the training session, and again 24 hours later.
During the training session itself, both the 16- to 18-year-olds and 20- to 30-year-olds improved their skills significantly more than the 8- to 10-year-olds.
"So it appears that both teenagers and younger adults are better equipped to quickly acquire new skills compared to children, who showed smaller and slower improvements. At least when it comes to short-term learning and motor skills which this study investigated,
While the researchers cannot pinpoint the exact reasons for why the adults learn faster, they have a few theories.
"The results demonstrate that the older the participants are, the more skillful they become during the early stages of training. This suggests that they get more out of the task introduction. We suspect that cognitive development and an increased ability to process information play a role—meaning adults may have more experience receiving instructions and translating them into action.
"The difference may also be because the fully developed nervous system of an adult provides better structural conditions for learning. In other words, after many years of schooling, adults may be more experienced learners and thereby more efficient at learning new things. The picture changes when it comes to retention.
"When the researchers looked at what happens from the end of training until the participants return the next day, the dynamic reverses. While the youngest participants actually improve overnight, adults lose some of their ability to perform. This means the youngest ones are better at consolidating and reinforcing their memory after they've practiced, According to the researchers, this suggests that sleep benefits children's learning and memory more. But other factors could also be at play. For example, older children and adults typically sleep less and have more "competing" activities throughout the day. Memory-consolidation processes in the nervous system continue for hours after the training ends. When a math class ends, the brain keeps working on what was taught, and in doing so, reinforces memory. Sleep is known to aid consolidation. But engaging in other activities in the hours after—especially those that involve learning—can interfere with memory processes and the consolidation of what was just learned. While the overall learning outcome doesn't vary drastically across age groups, the study does show that the learning process differs significantly depending on age, with underlying mechanisms influenced by the maturity of one's central nervous system.
Mikkel Malling Beck et al, Distinct mechanisms for online and offline motor skill learning across human development, Developmental Science (2024). DOI: 10.1111/desc.13536
Using personal care products during and after pregnancy can increase exposure to toxic chemicals
For people who are pregnant or nursing, more use of personal care products is associated with higher detectable levels of synthetic chemicals known to have adverse health effects, a new study by researchers has found.
The study, published in Environment International, found that using personal care products like nail polish, makeup and hair dye while pregnant or lactating is associated with significantly higher levels of per- and polyfluoroalkyl substances, known as PFAS, in blood plasma and breast milk.
While PFAS are ubiquitous in the environment, this study indicates that personal care products are a modifiable source of PFAS. People who are concerned about their level of exposure to these chemicals during pregnancy or while breastfeeding may benefit from cutting back on personal care products during those times.
PFAS are synthetic chemicals that have been used in consumer products and industrial settings since the 1950s due to their ability to resist oil, water and heat. The study notes that PFAS have been associated with a range of adverse health effects, including liver disease, cardiometabolic and cardiovascular issues, and various cancers.
While several studies have detected these chemicals in personal care products directly, few have evaluated whether using these products impacts internal PFAS concentrations.
This is important, she added, because exposure to PFAS during pregnancy could contribute to adverse birth outcomes such as decreased birth weight, preterm birth, some neurodevelopmental disorders and diminished vaccine response in children.
The analyzed data from the Maternal-Infant Research on Environmental Chemicals Study, which enrolled 2,001 pregnant people from 10 cities across Canada between 2008 and 2011. The researchers evaluated the contribution of the use of personal care products on PFAS concentrations in prenatal plasma (6 to 13 weeks gestation) and human milk (2 to 10 weeks postpartum). Participants reported frequency of use across eight product categories during the first and third pregnancy trimesters, one to two days postpartum, and 2 to 10 weeks postpartum.
In first-trimester pregnant people, the researchers found that higher use of nail care products, fragrances, makeup, hair dyes and hair sprays or gels was associated with higher plasma PFAS concentrations. Similar results were observed for third-trimester personal care product use and breast-milk PFAS concentrations at 2 to 10 weeks postpartum.
For instance, participants who wore makeup daily in the first and third trimesters had 14% and 17% higher plasma and breast-milkPFAS concentrations, respectively, compared to people who did not wear makeup every day. In addition, the researchers found that people using colored-permanent dye one to two days postpartum had higher PFAS levels (16% to 18% increases compared to never using them) in human milk concentrations.
The researchers noted that the study examined only four types of PFAS among thousands that are used in industry and commerce. Thus, the study likely underestimated the extent of exposure to all PFAS from these products during pregnancy.
Amber M Hall et al, Personal care product use and per- and polyfluoroalkyl substances in pregnant and lactating people in the Maternal-Infant Research on Environmental Chemicals study, Environment International (2024). DOI: 10.1016/j.envint.2024.109094
Virologist Beata Halassy treated her own breast cancer by injecting the tumour with viruses she grew in the lab. In 2020, Halassy discovered she had a second recurrence of breast cancer at the site of a previous mastectomy. To avoid another bout of chemotherapy,she self-administered experimental oncolytic virotherapy. Halassy has now been cancer-free for four years. Her decision to treat herself, and subsequently publish a report detailing the process, has sparked discussion about the ethics of self-experimentation and the risk it might encourage others to try unproven treatments. “It took a brave editor to publish the report,” says Halassy.
Oropouche virus transmission to unborn child confirmed
The first confirmed case of vertical transmission of Oropouche virus (OROV) has been reported by 23 researchers from eight distinct institutions in Brazil.
OROV, a zoonotic arbovirus, was first isolated from the blood of a charcoal worker with a high fever in 1955 on the Caribbean island of Trinidad. Outbreaks have typically occurred south of the Amazon, isolated within Amazonian villages.
In 2024, OROV infections were detected in previously non-endemic areas across all five Brazilian regions. These expansions into previously unaffected regions involve new virus variants emerging from genetic reassortment.
In a letter to the editor titled "A Case of Vertical Transmission of Oropouche Virus in Brazil,"publishedOctober 30, 2024, in theNew England Journal of Medicine, researchers report on a case from Ceará, a state historically free from OROV, finding its first infection case through active laboratory surveillance.
Subsequent investigations identified 171 cases, predominantly in the rural valleys of the Baturité Massif. Agricultural landscapes in this region favor the Culicoides paraensis midge, a small biting fly sometimes referred to as "no-see-ums" due to their tiny size. Culicoides is the primary vector for OROV transmission to humans.
A notable case involved a 40-year-old pregnant woman at 30 weeks gestation who developed fever, chills, muscle aches, and severe headache. Routine prenatal care had previously identified gestational diabetes, managed with metformin, and four routine obstetric ultrasounds.
On July 27, medical evaluation revealed light vaginal bleeding and dark discharge, with ultrasonography indicating fetal macrosomia.
By August 5, continued symptoms and decreased fetal movements led to the confirmation of fetal demise.
Molecular diagnostics confirmed acute OROV infection, ruling out dengue, Zika, chikungunya, and Mayaro viruses. Minimal invasive tissue sampling of the stillborn infant revealed OROV RNA in multiple fetal tissues, establishing vertical transmission.
Phylogenetic analysis using maximum-likelihood inference positioned the virus within the OROVBR-2019-2024 lineage, consistent with strains from the ongoing outbreak. These findings link the stillbirth directly to the current OROV spread in Brazil, highlighting the virus's potential risks during pregnancy.
The report should sound the alarm for health care providers to consider OROV infection in pregnant women presenting with fever and related symptoms in endemic or emerging regions.
Carlos Garcia Filho et al, A Case of Vertical Transmission of Oropouche Virus in Brazil, New England Journal of Medicine (2024). DOI: 10.1056/NEJMc2412812
Redefining net zero will not stop global warming, scientists say
This is really absurd. Governments and countries are trying to evade climate goals to stop global warming.
In a study, led by the University of Oxford's Department of Physics and published 18 November in Nature, an international group of authors who developed the science behind net zero demonstrate that relying on 'natural carbon sinks' like forests and oceans to offset ongoing CO2 emissions from fossil fuel use will not actually stop global warming.
The science of net zero, developed over 15 years ago, does not include these natural carbon sinks in the definition of net human-induced CO2 emissions.
Natural sinks play a vital role in moderating the impact of current emissions and draw down atmospheric CO2 concentrations after the date of net zero, stabilizing global temperatures. Yet governments and corporations are increasingly turning to them to offset emissions, rather than reducing fossil fuel use or developing more permanent CO2 disposal options.
Emissions accounting rules encourage this by creating an apparent equivalence between fossil fuel emissions and drawdown of CO2by some natural carbon sinks, meaning a country could appear to have 'achieved net zero' while still contributing to ongoing warming.
The authors call on governments and corporations to clarify how much they are counting on natural carbon sinks to meet their climate goals, as well as recognizing the need for "Geological Net Zero."
Geological Net Zero means balancing flows of carbon into and out of the solid Earth, with one ton of CO2committed to geological storage for every ton still generated by any continued fossil fuel use. Given the cost and challenges of permanent geological CO2storage, achieving Geological Net Zero will require a substantial reduction in fossil fuel use.
The authors stress the importance of protecting and maintaining natural carbon sinks while accepting that doing so cannot compensate for ongoing fossil fuel use. Total historical CO2emissions determine how much a country or company has contributed to the global need for ongoing natural carbon sinks.
We are already counting on forests and oceans to mop up our past emissions, most of which came from burning stuff we dug out of the ground. We can't expect them to compensate for future emissions as well. By mid-century, any carbon that still comes out of the ground will have to go back down, to permanent storage. That's Geological Net Zero. Countries report both emissions and removals, but using all removals in climate targets is a recipe for continued warming. Natural carbon sinks currently clean up around half our annual emissions for free, but this ecosystem service must be kept separate from the fossil emissions driving climate change. Relabeling things will not stop global warming, say the scientists. They stress that: It is a common assumption that removing carbon from the atmosphere to offset burning of fossil fuels is as effective as not burning fossil fuels in the first place. It is not. Offsetting continued fossil fuel use with carbon removal will not be effective if the removal is already being counted on as part of the natural carbon cycle and if the carbon is not permanently stored. Unless we can increase transparency in national Greenhouse gas reporting and target setting, offsets will become part of the problem instead of part of the solution. Land is limited, we rely on it for food, nature, biodiversity, leisure, water storage, and so on. It cannot offset more than a portion of fossil emissions even now, probably less in future, with worsening pressures on the biosphere such as population increase, fires, and drought.
"Giving carbon credits for natural processes that are happening anyway undermines trust in the whole idea of offsetting. We have to urgently protect natural carbon sinks, but there are more scientifically credible and equitable ways of doing this than relying on carbon offset markets." Is anybody listening?
Extreme heat weakens land's power to absorb carbon, analysis finds
A new European Space Agency-backed study shows that the extreme heat waves of 2023, which fueled huge wildfires and severe droughts, also undermined the land's capacity to soak up atmospheric carbon. This diminished carbon uptake drove atmospheric carbon dioxide levels to new highs, intensifying concerns about accelerating climate change.
Measurements from Hawaii's Mauna Loa Observatory showed that atmospheric carbonconcentrations surged by 86% in 2023 compared to the previous year, marking a record high since tracking began in 1958.
Despite this sharp increase, fossil fuel emissions only rose by about 0.6%, suggesting that other factors, such as weakened carbon absorption by natural ecosystems, may have driven the spike.
An international team of scientists analyzed global vegetation models and satellite data to investigate the underlying causes and deliver an expedited carbon budget report for 2023.
Typically, land absorbs roughly one-third of human-generated carbon dioxide emissions. However, the team's researchpublishedinNational Science Reviewreveals that in 2023, this capacity fell to just one-fifth of its usual level, marking the weakest land carbon sink performance in two decades.
Widespread wildfires across Canada and droughts in the Amazon in 2023 released about the same amount of carbon to the atmosphere as North America's total fossil fuel emissions, underscoring the severe impact of climate change on natural ecosystems.
The Amazon—one of the world's most crucial carbon sinks—is showing signs of long-term strain, with some regions shifting from absorbing carbon to becoming net sources of carbon emissions.
The researchers suggest that the declining capacity of Earth's land ecosystems to absorb carbon dioxide may indicate that these natural carbon sinks are nearing their limits and no longer able to provide the mitigation service they have historically offered by absorbing half of human-induced carbon dioxide emissions. Consequently, achieving safe global warming limits will require even more ambitious emission reductions than previously anticipated, the scientists say. The study also highlights that current climate models might be underestimating the rapid pace and impact of extreme events, such as droughts and fires, on the degradation of these crucial carbon reservoirs.
Piyu Ke et al, Low latency carbon budget analysis reveals a large decline of the land carbon sink in 2023, National Science Review (2024). DOI: 10.1093/nsr/nwae367
Why May 2024's aurora appeared a magenta color over Japan?
Around the world, the historic geomagnetic superstorm of late spring 2024 inspired millions of non-scientists around the world—many armed with highly sensitive smartphone cameras—to take a fantastic, unprecedented number of images of the aurora it produced.
In Japan, this widespread popular uptake of what is now quite advanced imaging technology (even if it is kept in everyone's pocket) proved to be a tremendous boon for atmospheric physicists and other scientists specializing in "space weather." It allowed them to discover why the Northern Lights over Japan appeared as a mysterious magenta color this time instead of the typical red that is observed when aurorae are visible over that country.
In early May this year, one of the most extreme geomagnetic storms in the history of recording such events hit the Earth's atmosphere. This great "storm" in space, composed of ionized particles, is what produces the aurora borealis, or Northern Lights, in the northern hemisphere and the aurora australis, or Southern Lights, in the southern hemisphere.
This time, however, the storm was so strong—the ninth most severe storm in the 110-year history of Japan's Kakioka Magnetic Observatory, one of the oldest geomagnetic stations in the world—that the polar lights could be photographed at much lower latitudes than normal.
Part 1
In Japan, space weather researchers took advantage of ordinary people taking pictures of the aurora with their smartphones to organize one of the densest citizen science observation efforts anywhere, despite being a low-latitude country where the aurora was somewhat fainter than in places like Canada or northern Europe.
The different colors of an aurora come from the emission of light from different atoms and molecules in the atmosphere when they are bombarded by the particles from space. The dramatic green hue seen in many photographs of the polar lights comes from atomic oxygen (single atoms of oxygen rather than molecular oxygen, or two oxygen atoms bound together) at the lower altitudes within the atmosphere that are visible to people. (The human eye is also just very sensitive to this color). At even lower altitudes, where atomic oxygen is less common, blue is more visible, and this comes from the greater presence of nitrogen.
At the very highest altitudes in the atmosphere, however, there is a lower concentration of atoms of any kind. The fewer collisions there result in a perception by humans of the excited atomic oxygen atoms as the color red. This is why the upper parts of the aurora curtains can appear as green fading into a scarlet hue. At low latitudes, as in Japan, normally there is no green at all, only red because only the upper part of the aurora can be seen above the horizon.
"Yet this time, weirdly, the images revealed a very clear and dominant magenta hue to the aurora 'curtains' over Japan, not red. To solve the mystery, the researchers quickly took to social media to encourage people to observe and report their sightings of the auroras, as well as to input data into a questionnaire asking about observation locations, time, elevation angles and other details, allowing researchers to analyze the auroras' characteristics in unprecedented detail.
Part 2
The effort resulted in an impressive 775 grassroots submissions, which the researchers then combined with satellite observations and advanced modeling techniques to explore the conditions that had led to the magenta aurora.
The elevation data from these citizen scientists proved to be particularly useful. The researchers used elevation angles to calculate the position of the aurora over time, and found that it was often a surprisingly high altitude of roughly 1,000 km above sea level—which should thus drive a red appearance. But on top of this, the time and season of year meant the atmosphere was more "preheated" ahead of the aurora, in turn driving an upwelling of ionized molecular nitrogen—what is usually responsible for a blue hue. "Blue plus red makes us see magenta. And the magenta was made all the more visible and vibrant by the sheer volume of solar activity, even though, ironically, the preheating would also have worked to reduce the peak brightness of the aurora." Better understanding of magnetic storms goes beyond explaining why humans see the pretty colors of aurorae; these storms can have profound, negative impacts on satellite operations, GPS systems, power grids and even the safety of passengers and crews aboard high-altitude flights.
Ryuho Kataoka et al, Extended magenta aurora as revealed by citizen science, Scientific Reports (2024). DOI: 10.1038/s41598-024-75184-9
Confinement may affect how we smell and feel about food
New research found confined and isolating environments changed the way people smelled and responded emotionally to certain food aromas.
The team in this study compared 44 people's emotional responses and perception of eight food aromas in two environmental scenarios: sitting in reclined chairs that mimic astronauts' posture in microgravity; and then in the confined setting of the International Space Station (ISS), which was simulated for participants with virtual reality goggles.
The aromas the team tested on participants were vanilla, almond, lemon, lemon myrtle, eucalyptus, peppermint, vinegar and lemongrass.
The research, published in Food Research International, builds on previous work by the team and aims to help explain why astronauts report meals taste different in space and struggle to eat their normal nutritional intake over long missions, which has been reported in the news recently.
The study has broader implications for further research to improve the diets of isolated people, including nursing home residents, by personalizing aromas to enhance the flavor of their food.
Part 1
Lemongrass consists of a more floral and earthy aroma, while the other aromas are pungent, spicy or sweet. This difference in profile may explain why lemongrass seemed less intense in the VR setting compared to the microgravity posture. In an Earth-like setting, eating was often social, but eating in space on long missions can feel quite different. Pilot studies [published open-access in the journal Science Talks] show that spending 10 minutes in VR can induce feelings of confinement, highlighting VR's effectiveness over other methods such as immersive screens.
"Results indicate that a remote, confined environment such as the ISS and a significant variation in personal sensitivities influence aroma perception, making certain foods smell strange. Space studies often emphasized microgravity as the main contributing factor to food's different taste, but the team's findings underscored the impact of confined and isolated environments. This research opens possibilities for personalized meal plans for astronauts and individuals living alone on Earth, showcasing VR's potential to explore variations in eating when stressed. In the VR setting, participants reporting positive emotions perceived stronger aromas.This link between stress and vinegar may help explain why astronauts like to eat certain foods in microgravity that they don't normally enjoy on Earth.
Food odour perception and affective response in virtual spacecraft and microgravity body posture (1-G) – potential ground-based simulations,Food Research International(2024).
Julia Low et al, Development of a virtual reality spacecraft environment as a ground-based analog for collecting space food sensory data ('Food in Space'),Science Talks(2024).DOI: 10.1016/j.sctalk.2024.100391
Alicia Tran et al, Exploring fundamentals of immersive environment setups on food sensory perception in space contexts,Science Talks(2024).DOI: 10.1016/j.sctalk.2024.100403
Scientists transform blood into regenerative materials, paving the way for personalized, 3D-printed implants
Scientists have created a new 'biocooperative' material based on blood, which has been shown to successfully repair bones, paving the way for personalized regenerative blood products that could be used as effective therapies to treat injury and disease.
Researchers have used peptide molecules that can guide key processes taking place during the natural healing of tissues to create living materials that enhance tissue regeneration. The research is published in Advanced Materials.
Most of our body tissues have evolved to regenerate ruptures or fractures with remarkable efficacy, as long as these are small in size. This healing process is highly complex. The initial stages rely on liquid blood forming the solid regenerative hematoma (RH), a rich and living microenvironment comprising key cells, macromolecules, and factors that orchestrate regeneration. The team developed a self-assembling methodology where synthetic peptides are mixed with whole blood taken from the patient to create a material that harnesses key molecules, cells, and mechanisms of the natural healing process. In this way, it was possible to engineer regenerative materials capable of not only mimicking the natural RH, but also enhancing its structural and functional properties. These materials can be easily assembled, manipulated, and even 3D printed while maintaining normal functions of the natural RH, such as normal platelet behavior, generation of growth factors, and recruitment of relevant cells important for healing. With this method, the team has shown the capacity to successfully repair bone in animal models using the animal's own blood.
Soraya Padilla‐Lopategui et al, Biocooperative Regenerative Materials by Harnessing Blood‐Clotting and Peptide Self‐Assembly, Advanced Materials (2024). DOI: 10.1002/adma.202407156
Scientists convert plastics into soaps and detergents
Researchers found a way to convert certain plastics into soaps, detergents, lubricants, and other products.
The process has two steps. It first involved using thermolysis, or breaking down a substance—in this case, plastic—by using heat. Plastic placed in a reactor built by the research team and heated to between 650 and 750 degrees Fahrenheit broke down into chemical compounds, leaving a mixture of oil, gas, and residual solids.
The key to this first step was breaking down the polypropylene and polyethylene molecules that make up plastic within a certain carbon range, and Liu and his team were able to accomplish this.
The residual solids left behind were minimal, and the gas could be captured and used as fuel. The oil, though, was the product of the most interest here.
They were also was able to functionalize, or change the chemistry, of the oil into molecules to be converted into soaps, detergents, lubricants, and other products.
These materials are stable. You could use them to wash your hands and dishes. The researchers have used them to wash their lab glassware in the laboratory.
The process, which took less than a day, led to almost zero air pollution output, thus offering clues to a desperately needed solution to a global problem.
Nuwayo Eric Munyaneza et al, Chain-length-controllable upcycling of polyolefins to sulfate detergents, Nature Sustainability (2024). DOI: 10.1038/s41893-024-01464-x
Researchers uncover how blood pressure drugs harm kidneys
Commonly prescribed drugs used to treat high blood pressure have been shown to, over time, wreck the kidneys' ability to filter and purify blood. How does this happen?
Researchers found that the drugs essentially rewire the kidneys to do something other than the important work of filtering blood. The kidneys start producing more of a hormone called renin; nerve endings grow excessively; cells lining the kidneys' tiny blood vessels get too large; scars form and spread; and inflammation sets in, which "can take a terrible toll on the kidney.
The result, outlined in the researchers' paper in the journal Circulation Research, is a "silent but serious" vascular disease where the kidneys become zombie-like, changing into something unwanted and unwelcome while abandoning their critical duties.
Now that they know the cause, researchers say the next step is to figure out how to use the effective blood pressure drugs known as renin-angiotensin system inhibitors—often called RAS inhibitors—while stopping the kidney-damaging effects.
RAS inhibitors, which include the generics enalapril, lisinopril, ramipril and others, are commonly prescribed when a patient is first diagnosed with high BP.
The drugs work by relaxing blood vessels and allowing blood to flow more freely. The medicines are widely used and generally considered safe, researchers say, but are not without risk. Doctors have long warned patients that certain blood pressure medications could cause kidney damage, often first noticed as a reduction in the frequency of urination, swelling in the legs or feet, or seizures.
Now that scientists understand what is causing the kidney changes, they can look for ways to stop it.
These findings may open new avenues for the prevention of adverse effects when treating hypertension.
Manako Yamaguchi et al, Transformation of the Kidney into a Pathological Neuro-Immune-Endocrine Organ, Circulation Research (2024). DOI: 10.1161/CIRCRESAHA.124.325305
High exposure to everyday chemicals linked to asthma risk in children
A new study by researchers at Kumamoto University sheds light on a potential link between exposure to certain everyday chemicals during pregnancy and the development of asthma in children. The study analyzed data from over 3,500 mother-child pairs as part of the Japan Environment and Children's Study (JECS), a large-scale nationwide research project.
researchers measured 24 types of phenols in urine samples collected from pregnant women. They then tracked the health of their children until the age of four.
The study is published in the journal Environmental Pollution.
High levels of butylparaben, a chemical commonly used in personal care products like lotions and shampoos, during early pregnanacy were associated with a 1.54-fold increase in the odds of asthma development in children (Odds Ratio: 1.54).
Exposure to 4-nonylphenol, a chemical found in some cleaning products and plastics, showed a striking gender-specific effect. Boys born to mothers exposed to this chemical had 2.09 times higher odds of developing asthma, while no such association was observed in girls.
Phenols, including parabens and alkylphenols, are widely used in consumer products for their preservative and antimicrobial properties. While their use is considered safe in small amounts, their potential as endocrine disruptors raises concerns about long-term health effects, such as the recent increase in allergenic diseases such as asthma, particularly during sensitive periods like pregnancy.
The findings highlight the importance of understanding how everyday chemical exposures might contribute to respiratory and allergic conditions in children.
Shohei Kuraoka et al, Association of phenol exposure during pregnancy and asthma development in children: The Japan Environment and Children's study, Environmental Pollution (2024). DOI: 10.1016/j.envpol.2024.124801
By exerting 'crowd control' over mouse cells, scientists make progress towards engineering tissues Genes aren't the sole driver instructing cells to build multicellular structures, tissues, and organs. In a paper published in Nature Communications, scientists characterize the influence of another important developmental driver: cell density, or how loosely or tightly cells are packed into a given space.
In both computational models and laboratory experiments, the team of scientists used cell density as an effective tool for controlling how mouse cells pattern themselves into complex structures.
This paper represents progress towards their big picture goal of engineering synthetic tissues. Synthetic tissues could have endless medical applications, ranging from testing potential drugs or therapies to providing grafts or transplants for patients.
The study used two types of mouse cells—connective tissue cells and stem cells—engineered to carry a synthetic cellular communication system or "genetic circuit. This circuit is based on something they developed called "synNotch," which is a protein that scientists genetically engineer into a cell to serve as a "sensor."
Located on a cell's surface, this protein-based sensor recognizes an external signal that triggers the cell to respond—usually by turning on a user-defined gene.
For this particular series of experiments, the scientists used synNotch to turn on a circuit that includes green fluorescence and a way to propagate the signal further—although it could be used to turn on any gene. The fluorescence made it easy to observe cells as they formed patterns. For example, in a field of cells, scientists could create a pattern of green fluorescent rings emanating from a central point.
While conducting these experiments, the scientists noticed that genetically identical cells did not always produce the same patterns.
So that was puzzling at the beginning. When the researchers looked at it more carefully, they started seeing that there was a gradient of cell density that seemed to correlate with differences in patterning.
Above a certain cell density, synNotch exerted a weaker effect and didn't produce the same patterns. Further complicating matters, cell density constantly shifted as cells proliferated at ever changing rates—interacting in complex ways with the synNotch genetic circuit.
The scientists then built a computational model that could predict and clarify this complex and dynamic cell behaviour. It helped guide them to think about how the cell density, proliferation rate, signaling, and all these different things conspire.
Guided by the computational model, the scientists were able to use cell density to generate a variety of predictable fluorescent patterns that developed over specific timeframes.
To understand how cell density was exerting these effects, the scientists conducted a series of experiments that yielded a surprising discovery. Greater cell density induces stress that leads to a quicker breakdown of not only synNotch in particular, but also cell surface sensors in general.
This means that cell density is a broadly applicable tool for guiding both engineered and naturally occurring cells to build a vast array of structures, tissues, and organs.
Nature has relied on cell density in conjunction with genetic circuits to generate the remarkable diversity of multicellular structures, tissues, and organs.
Now we can co-opt this same strategy to advance our efforts to build synthetic multicellular structures—and eventually tissues and organs—for regenerative medicine, say the scientists.
Research reveals even single-cell organisms exhibit habituation, a simple form of learning
Up until recently, habituation -- a simple form of learning -- was deemed the exclusive domain of complex organisms with brains and nervous systems, such as worms, insects, birds, and mammals. But a new study offers compelling evidence that even tiny single-cell creatures such as ciliates and amoebae, as well as the cells in our own bodies, could exhibit habituation akin to that seen in more complex organisms with brains.
A dog learns to sit on command, a person hears and eventually tunes out the hum of a washing machine while reading … The capacity to learn and adapt is central to evolution and, indeed, survival.
Habituation involves the lessening response to a stimulus after repeated exposure. Think of the need for a third espresso to maintain the same level of concentration you once achieved with a single shot.
Up until recently, habituation -- a simple form of learning -- was deemed the exclusive domain of complex organisms with brains and nervous systems, such as worms, insects, birds, and mammals.
But a new study, published Nov. 19 in Current Biology, offers compelling evidence that even tiny single-cell creatures such as ciliates and amoebae, as well as the cells in our own bodies, could exhibit habituation akin to that seen in more complex organisms with brains.
This finding opens up an exciting new mystery for us: How do cells without brains manage something so complex?
The results add to a small but growing body of work on this subject. Earlier work led by Gunawardena found that a single-cell ciliate showed avoidance behavior, not unlike the actions observed in animals that encounter unpleasant stimuli.
Instead of studying cells in a lab dish, the scientists used advanced computer modeling to analyze how molecular networks inside ciliate and mammalian cells respond to different patterns of stimulation. They found four networks that exhibit hallmarks of habituation present in animal brains.
These networks shared a common feature: Each molecular network had two forms of "memory" storage that captured information learned from the environment. One memory decayed much faster than the other -- a form of memory loss necessary for habituation, the researchers noted. This finding suggests that single cells process and remember information over different time spans.
Studying habituation in single cells could help propel understanding of how learning in general works, the researchers said. The findings also cast the humble single-cell creatures in a new, more tantalizing light: They are not merely molecular machines packed in microscopic bodies, but they are also agents that can learn.
Practical applications of this work:
One daring idea would be to apply the concept of habituation to the relationship between cancer and immunity.
Tumors are notoriously good evaders of immune surveillance because they trick immune cells into viewing them as innocent bystanders. In other words, the immune cells responsible for recognizing cancer may get somehow habituated to the presence of a cancer cell -- the immune cell gets used to the stimulus and no longer responds to it.
If we knew how these false perceptions get encoded in immune cells, we may be able to re-engineer them so that immune cells begin to perceive their environments correctly, the tumor becomes visible as malign, and they get to work.
Lina Eckert, Maria Sol Vidal-Saez, Ziyuan Zhao, Jordi Garcia-Ojalvo, Rosa Martinez-Corral, Jeremy Gunawardena. Biochemically plausible models of habituation for single-cell learning. Current Biology, 2024; DOI: 10.1016/j.cub.2024.10.041
Astronauts found to process some tasks slower in space, but no signs of permanent cognitive decline
A stay in space exerts extreme pressures on the human body. Astronauts' bodies and brains are impacted by radiation, altered gravity, challenging working conditions, and sleep loss—all of which could compromise cognitive functioning. At the same time, they are required to perform complex tasks, and minor mistakes can have devastating consequences.
Working with 25 astronauts who spent an average of six months on the International Space Station (ISS), researchers have examined changes in a wide range of cognitive performance domains. This dataset makes up the largest sample of cognitive performance data from professional astronauts published to date.
The research shows that there is no evidence of any significant cognitive impairment or neurodegenerative decline in astronauts spending six months on the ISS. Living and working in space was not associated with widespread cognitive impairment that would be suggestive of significant brain damage.
The results showed that responses to tasks assessing processing speed, working memory, and attention were slower than on Earth, but they were no less accurate. These changes, however, did not persist equally long.
Slowed performance on attention, for example, was only observed early during the mission, while slowed performance on processing speed did not return to baseline levels until after the mission ended and the crew were back on Earth.
Overall, astronauts' cognitive performance was stable, and the researchers did not find evidence that would suggest damage to the central nervous system during a six-month space mission.
Cognitive Performance in ISS Astronauts on 6-month Low Earth Orbit Missions, Frontiers in Physiology (2024). DOI: 10.3389/fphys.2024.1451269
Ethiopian wolves seen feeding on nectar of red hot poker flowers
Strange things happen in nature!
New findings, published in the journal Ecology, describe a newly documented behavior of Ethiopian wolves (Canis simensis).
Researchers observed Ethiopian wolvesforaging for the nectar of the Ethiopian red hot poker (Kniphofia foliosa) flower. Some individuals would visit as many as 30 blooms in a single trip, with multiple wolves from different packs exploiting this resource. There is also some evidence of social learning, with juveniles being brought to the flower fields along with adults.
In doing so, the wolves' muzzles become covered in pollen, which they could potentially transfer from flower to flower as they feed. This novel behavior is perhaps the first known plant-pollinator interaction involving a large predator, as well as the only large meat-eating predator ever to be observed feeding on nectar.
Sandra Lai et al, Canids as pollinators? Nectar foraging by Ethiopian wolves may contribute to the pollination of Kniphofia foliosa, Ecology (2024). DOI: 10.1002/ecy.4470
Scientists discover the molecular composition of potentially deadly venomous fish
New research in FEBS Open Bio reveals insights into the venom of two of the most venomous fish species on Earth: the estuarine stonefish (Synanceia horrida) and the reef stonefish (Synanceia verrucosa), which are typically found in the warm and shallow regions of the Indo-Pacific region, the Persian Gulf, and the Red Sea.
Through multiple analytical techniques, investigators discovered the presence of three neurotransmitters new to stonefish venom, namely gamma-aminobutyric acid (GABA), choline, and 0-acetylcholine.
Although these molecules have been previously found in venoms from other species, such as hornets and spiders, this is the first report of a fish venom that contains GABA, which is capable of modulating cardiovascular function with a range of effects including increased heart rate and low blood pressure.
Characterization of the specific composition of each of these fish species' venom not only provides us with a better understanding of envenomation mechanisms, which are needed for the development of targeted treatments against venom effects, but may also aid in the exploration and development of venom-derived compounds in drug discovery.
Silvia Luiza Saggiomo et al, Interrogating stonefish venom: small molecules present in envenomation caused by Synanceia spp., FEBS Open Bio (2024). DOI: 10.1002/2211-5463.13926
Weight-loss drug found to shrink heart muscle in mice and human cells
Trendy weight-loss drugs making headlines for shrinking waistlines may also be shrinking the human heart and other muscles, according to a new study in JACC: Basic to Translational Science. The authors say the research should serve as a "cautionary tale" about possible long-term health effects of these drugs.
Researchers set out to study why a reported side-effect of the leading weight-loss drug Ozempic is the loss of skeletal muscle.
Ozempic, known medically as semaglutide, was originally designed to help adult patients with type 2 diabetes control their blood sugar. However, this drug—and a host of others in this class of medication—are also being touted for their effectiveness as an anti-obesity medication.
Using mice for the study, the researchers found that heart muscle also decreased in both obese and lean mice. The systemic effect observed in mice was then confirmed in cultured human heart cells.
Matthew D. Martens et al, Semaglutide Reduces Cardiomyocyte Size and Cardiac Mass in Lean and Obese Mice, JACC: Basic to Translational Science (2024). DOI: 10.1016/j.jacbts.2024.07.006
Females sleep less and awaken more frequently than males, which may have broad implications for medical research
Females sleep less, wake up more often and get less restorative sleep than males, according to a new animal study by researchers.
The findings, published in the journal Scientific Reports, shed new light on what may underlie sleep differences in men and women and could have broad implications for biomedical research, which for decades has focused primarily on males.
In humans, men and women exhibit distinct sleep patterns, often attributed to lifestyle factors and caregiving roles. However, these new results suggest that biological factors may play a more substantial role in driving these sleep differences than previously recognized.
Sleep research has exploded in recent years, with thousands of animal studies exploring how insufficient sleep impacts risk of diseases like diabetes, obesity, Alzheimer's and immune disorders—and how such diseases impact sleep.
But many of those results may have been skewed due to a lack of female representation, the study suggests.
The question the female researchers now ask is: Are we creating too much stress for ourselves because we don't sleep as much as our husband or partner and think our sleep is poor when actually that is a normal sleep profile for ourselves?
The authors hope their findings inspire more research into underlying biological differences. More importantly, they hope the study prompts scientists to re-evaluate how they do research and interpret the results.
Grant S. Mannino et al, The importance of including both sexes in preclinical sleep studies and analyses, Scientific Reports (2024). DOI: 10.1038/s41598-024-70996-1
Healthy women have cells that resemble breast cancer, study finds
A new study from cancer researchers finds that, in healthy women, some breast cells that otherwise appear normal may contain chromosome abnormalities typically associated with invasive breast cancer. The findings question conventional thinking on the genetic origins of breast cancer, which could influence early cancer detection methods.
The study, published recently in Nature, discovered that at least 3% of normal cells from breast tissue in 49 healthy women contain a gain or loss of chromosomes, a condition known as aneuploidy, and that they expand and accumulate with age. This poses questions for our understanding of "normal" tissues, according to principal investigator of this research.
As researchers continue to develop earlier detection methods using molecular diagnostics along with ductal carcinoma in situ (DCIS) and biopsies, these findings pose a challenge and highlight the potential risk of identifying false positives, as the cells can mistakenly be confused with invasive breast cancer.
A cancer researcher or oncologist seeing the genomic picture of these normal breast tissue cells would classify them as invasive breast cancer.
"We've always been taught that normal cells have 23 pairs of chromosomes, but that appears to be inaccurate because every healthy woman that we analyzed in our study had irregularities, bringing up the very provocative question about when cancer actually occurs", say the researchers.
The study builds upon their previous work on the Human Breast Cell Atlas, which profiled over 714,000 cells to generate a comprehensive genetic map of normal breast tissue at the cellular level.
Yiyun Lin et al, Normal breast tissues harbour rare populations of aneuploid epithelial cells, Nature (2024). DOI: 10.1038/s41586-024-08129-x
In 1896, German chemist Emil Fischer noted something very strange about a molecule named acetaldehyde phenylhydrazone. Identical batches of the crystalline compound appeared to have wildly different melting points.
Some batches, he found, melted at temperatures of around 65 degrees Celsius (149 Fahrenheit). Others at 100 degrees Celsius. It was, in a word, utterly bizarre. No other substance was known to behave this way. Nor should it.
According to the laws of thermodynamics that describe the way the physical world behaves, such a result should be impossible.
More than 120 years after Fischer's original discovery, in 2019, an international team of researchers led by chemist Terry Threfall of the University of Southampton in the UK finally found and published the answer. Fischer (who went on to win a 1902 Nobel prize for other work, so he was clearly no quack) had observed something real; but not, as it would turn out, anything that would break thermodynamics.
The culprit? An absolutely miniscule contamination, so small that it is all but undetectable. When acetaldehyde phenylhydrazone melts, it becomes one of two liquids, based on whether the compound has been exposed to a base or an acid. The former appears at the higher melting point; and the latter at the lower.
The observation of such behavior will be exceedingly rare because it depends on the molecules in the crystal and in the liquid having different geometries, which is unusual. Furthermore, it depends also on the conversion by acid being both possible and rapid.
The compound is made by dissolving solid acetaldehyde and adding both liquid phenylhydrazine and aqueous ethanol, and chilling until the mixture freezes and forms solid crystals. To then discover the melting point of the newly formed acetaldehyde phenylhydrazone, you have to re-melt it.
This is where the problems emerged. To understand why acetaldehyde phenylhydrazone melts at two distinct temperatures, the researchers first investigated its solid form. But the most cutting edge probes failed to turn up an answer.
All analyses, performed by Threlfall's team and other recent efforts, failed to find a single difference between acetaldehyde phenylhydrazone samples that melted at the lower temperature, and samples that melted at the higher. These techniques included X-ray diffraction, nuclear magnetic resonance, and IR spectroscopy. As far as scientists could tell, the crystals were identical. The next step was to investigate the liquid the crystals became after melting.
And there, the researchers got a result. There was a subtle, and temporary, but distinct difference. Although the compounds had the same molecular formula, the structure of the initial melt was slightly different, depending on the temperature.
The compound contains a methyl group that is able to have two distinct configurations, known as the Z isomer and the E isomer.
In its solid phase, the material almost exclusively consists of the Z isomer.
The most stable liquid phase is a mix of about one-third Z isomer to two-thirds E isomer. The lower of the two melting points immediately produces the Z and E mix, while the higher melting point is entirely Z, before switching to part E. Part 2
A clue was given in a 1905 paper, which pointed out that acetaldehyde phenylhydrazone was extremely sensitive to acid. Threlfall and his team tried exposing their samples to vapors of acid and ammonia. And they found that exposure to just a tiny bit of one or the other could reliably influence the compound's melting point. The acid acts as a catalyst to speed the shift from the Z to E isomer, lowering the melting point in the process. If an element or compound can exist in two or more distinct crystalline forms, then each form will have different Gibbs energies and melt at its own distinct temperature. In this case, the molecules of the crystal are in the cis geometry – of groups pointing towards each other – and melt to an identical geometry in the absence of acid at 100 degrees Celsius. However, in the presence of even a trace of acid, the molecules convert on melting to the trans geometry of groups pointing away from each other. This liquid has a smaller Gibbs energy and is more stable, so the melting point becomes 65 degrees Celsius."
It's similar to the effect salt has on water: adding salt to a pot of water raises the freezing and boiling points. Where it takes a lot of salt to invoke a significant change to water's phase transitions, it takes so little acid to alter acetaldehyde phenylhydrazone that it took more than a century – and Threlfall and his colleagues a decade – to figure it out.
This research is a real testament to human curiosity and tenacity. And it gives us hope for the future. How many more mysteries will be solved in the years stretching into a glittering future of discovery?
Cadavers could be bone-marrow donors A new technique for collecting bone-marrow stem cells from a cadaver’s spinal column could provide transplants for people with blood cancers. A company called Ossium Health is creating a bank of cryopreserved marrow from organ donors with diverse genetic backgrounds. Unlike solid organ donors, a bone-marrow donor must be a very close genetic match to the recipient. This presents a particular challenge when trying to find donors for people from racial minority groups, who are underrepresented in donor registries. The cadaver bank could widen the potential donor pool, although it is still unclear whether the freezing process could damage the stem cells.
Neanderthal adhesive manufacturing site found in Gibraltar cave
Cut into a Gibraltar cliff face overlooking the Alboran Sea, a cave opening leads back in time to one of the earliest manufacturing sites on the planet—a Neanderthal-built tar distillation oven hidden for 65,000 years.
Researchers have discovered a complex Neanderthal hearth structure in Vanguard Cave. Middle Paleolithic stone artifacts and residues suggest Neanderthals produced tar from rockrose plants (Cistaceae) here, showing off their advanced fire management and technological capabilities.
Neanderthals used fire for warmth, light, cooking, landscape clearing, and extracting adhesive tar from specific plants and trees. Evidence of their use of fire in tar extraction is based on the composition of the tar residues left on tools. Tar was used as an adhesive for hafting stone tools to wooden handles, representing a significant advancement in tool-making, predating current modern human tar adhesive use by more than 100,000 years.
While the techniques Neanderthals used to extract tar have been previously back-engineered to suggest the use of underground fire pits, direct evidence of these pits has been missing from the record.
In the current study, "A Neanderthal's specialized burning structure compatible with tar obtention," published in Quaternary Science Reviews, researchers analyzed a hearth pit structure in Vanguard Cave, employing geochemical, mineralogical, palynological and micromorphological methods.
They identified a central fire pit with two opposite-sided trenches, revealing a crust of altered rocks and sediment due to prolonged fire use. This structure aligns with theoretical models requiring specialized heating installations for tar production under low-oxygen conditions.
Organic geochemical analysis revealed the presence of levoglucosan and significant amounts of retene in the structure's matrix, compounds associated with the combustion of resinous plant materials. Lipid analysis showed straight-chain n-alkanes of odd carbon numbers and n-alkanols of even carbon numbers, biomarkers indicative of fresh leaf wax from plants like rockrose.
Charcoal analysis uncovered partially vitrified remains of Cistaceae, or rockrose family plants, suggesting incomplete combustion under controlled conditions. Less than 10% of the charcoal was from conifer wood.
Palynological examination indicated the presence of abundant pollen grains within the structure, whereas surrounding sediments were free of pollen. This suggests the deliberate introduction of plant materials into the hearth by Neanderthals.
Micromorphological analysis showed no evidence of clay heating above 500°C, indicating that the structure was used for controlled low-temperature processes compatible with tar production.
Carbonate rocks within the structure appear placed intentionally, likely employed to maintain a seal composed of guano and sand. This seal would create a low-oxygen environment essential for effective tar distillation.
To test their hypothesis, the team conducted experimental archaeology by building a similar structure and using it to heat rockrose leaves under low-oxygen conditions. The experiment successfully produced tar sufficient to haft stone spearheads, using only tools and materials available to Neanderthals in the area. Findings show Neanderthals organized complex fire-related activities by constructing specialized hearths for tar extraction. This confirms a level of cognitive complexity and cultural development previously expected based on their use of manufactured materials.
Juan Ochando et al, A Neanderthal's specialised burning structure compatible with tar obtention, Quaternary Science Reviews (2024). DOI: 10.1016/j.quascirev.2024.109025
Study reveals RNA's unknown role in DNA damage repair
A multi-institutional team of researchers has discovered a previously unknown role for RNA.
RNA molecules are best known as protein production messengers. They carry genetic instructions from DNA to ribosomes—the factories inside cells that turn amino acids into the proteins necessary for many cell functions. But this study found that RNA can also help cells repair a severe form of DNA damage called a double-strand break, or DSB.
A DSB means both strands of the DNA helix have been severed. Cells have the tools to make some repairs, but a DSB is significant damage—and if not properly fixed can lead to mutations, cell death, or cancer. (Interestingly, cancer treatments, like chemotherapy and radiation, can also cause DSBs.)
When a DSB happens in DNA, it's like a load-bearing beam in a building breaking. A careful, precise repair is needed to ensure the building's—or the DNA's—stability. The pieces must be rejoined accurately to prevent further damage or mutation. Repairing a damaged building requires having a reliable foreman on the job site. A DSB requires something very similar.
A key mechanism the researchers identified is that RNA can help position and hold the broken DNA ends in place, facilitating the repair process.
Specifically, they found that RNA molecules and the broken section of DNA can match up like puzzle pieces. When RNA has this kind of complementarity with the DNA break site, it acts as a scaffold, or a guide, beyond its traditional coding function, showing the cellular machinery where to make repairs. Over millennia, cells have evolved complex mechanisms to fix DSB, each of them functioning like different tools from the same toolbox.
This research work showed that RNA can influence which tools are used, depending on its complementarity to the broken DNA strands. This means that in addition to being the important protein production messenger, RNA acts as both a foreman and laborer when it comes to DNA repair.
A deeper understanding of RNA's role in DNA repair could lead to new strategies for strengthening repair mechanisms in healthy cells, potentially reducing the harmful effects of treatments like chemotherapy and radiation.
Youngkyu Jeon et al, RNA-mediated double-strand break repair by end-joining mechanisms, Nature Communications (2024). DOI: 10.1038/s41467-024-51457-9
Dr. Krishna Kumari Challa
Cholesterol may not be the only lipid involved in trans fat-driven cardiovascular disease
Excess cholesterol is known to form artery-clogging plaques that can lead to stroke, arterial disease, heart attack, and more, making it the focus of many heart health campaigns. Fortunately, this attention to cholesterol has prompted the development of cholesterol-lowering drugs called statins and lifestyle interventions like dietary and exercise regimens. But what if there's more to the picture than just cholesterol?
New research from Salk Institute scientists describes how another class of lipids, called sphingolipids, contributes to arterial plaques and atherosclerotic cardiovascular disease (ASCVD). Using a longitudinal study of mice fed high-fat diets—with no additional cholesterol—the team tracked how these fats flow through the body and found the progression of ASCVD induced by high trans fats was fueled by the incorporation of trans fats into ceramides and other sphingolipids. Knowing that sphingolipids promote atherosclerotic plaque formation reveals another side of cardiovascular disease in addition to cholesterol.
The findings, published in Cell Metabolism, open an entirely new avenue of potential drug targets to address these diseases and adverse health events like stroke or heart attacks.
When dietary fats enter the body through the foods we eat, they must be sorted and processed into compounds called lipids, such as triglycerides, phospholipids, cholesterol, or sphingolipids. Lipoproteins—like the familiar HDL, LDL, and VLDL—are used to transport these lipids through the blood.
Sphingolipids have become useful biomarkers for diseases like ASCVD, non-alcoholic fatty liver disease, obesity, diabetes, peripheral neuropathy, and neurodegeneration. However, it is unclear exactly how the incorporation of different dietary fats into sphingolipids leads to the development of ASCVD.
The fate of dietary fat is often determined by the protein that metabolizes it.
The team suspected that trans fats were being incorporated into sphingolipids by SPT, which, in turn, would promote the excess lipoprotein secretion into the bloodstream that causes ASCVD.
To test their theory, they compared the processing of two different fats, cis fats and trans fats. The difference between these two comes down to the placement of a hydrogen atom; cis fats, found in natural foods like fish or walnuts, have a kink in their structure caused by two side-by-side hydrogen atoms, whereas trans fats, found in processed foods like margarine or anything fried, have a straight-chain structure caused by two opposing hydrogen atoms. Importantly, the kink in cis fats means they cannot be tightly packed—a positive feature for avoiding impenetrable clogs.
The researchers combined mouse model dietary manipulation with metabolic tracing, pharmacological interventions, and physiological analyses to answer their question—what is the link between trans fats, sphingolipids, and ASCVD?
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The researchers found the incorporation of trans fats through SPT increased lipoprotein secretion from the liver, which then promoted the formation of atherosclerotic plaques.
In the end, they saw mice consuming a high trans fat diet were producing trans fat-derived sphingolipids that promoted the secretion of VLDL from the liver into the bloodstream. This, in turn, accelerated the buildup of atherosclerotic plaques and the development of fatty livers and insulin dysregulation. High cis-fat diet mice, on the other hand, experienced shorter-term, less harmful effects like weight gain.
Jivani M. Gengatharan et al, Altered sphingolipid biosynthetic flux and lipoprotein trafficking contribute to trans-fat-induced atherosclerosis, Cell Metabolism (2024). DOI: 10.1016/j.cmet.2024.10.016
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Scientists Put Cats in Microgravity to See What Would Happen
There is, perhaps, no animal on this planet as lithe as the simple domestic cat. And not least in their bag of acrobatic tricks is one for which they are well-known: the ability to land, safely, on their velvet paws, when subjected to a tumble.
In the 1950s, humans discovered parabolic flight: the ability to simulate zero-G conditions using specially-designed aircraft plummeting along a precise flight trajectory. And with that came a devilish thought. What would happen to a cat's ability to land on its feet if they can't tell the difference between up and down?
So, this is what the bright minds at the US Air Force Aerospace Medical Research Lab decided to find out.
Parabolic flight is not true microgravity, but a brief experience of its effect. Just as a rapid descent in an elevator can make you feel lighter in your loafers, passengers on an aircraft will experience weightlessness while rapidly descending from a high altitude to a lower one. It's pretty disorienting, earning parabolic flight the nickname 'vomit comet' for good reason.
https://spacemedicineassociation.org/download/history/history_files...
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The first experiments were conducted on board a Convair C-131 Samaritan, and yes, there is absolutely video of the proceedings. A similar experiment involved releasing pigeons inside the C-131 during parabolic flight.
It's fascinating to watch. The narration for the video says the cats' "automatic reflex action is almost completely lost under weightlessness". Almost – but not quite. Although the cats seem disoriented, they are still able to twist and turn their bodies around as they try to figure out where they are going to fall.
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Blood vessel-like coating could make medical devices safer for patients
Researchers have developed a coating that could make medical devices safer for millions of patients, reducing the risks associated with blood clots and dangerous bleeding. The work has been published in Nature Materials.
The new material, designed to mimic the natural behavior of blood vessels, could allow for safer use of blood-contacting devices like catheters, stents, blood-oxygenation machines and dialysis machines—especially in cases where blood clots are a significant concern.
This discovery could be a transformative step in the development of safer medical devices. By designing a coating that mimics the body's natural approach to preventing clots, researchers have created a solution that could dramatically reduce the need for risky blood thinners before and after patients use these devices.
Thrombosis, or clot formation, is a major challenge when blood-contacting devices are used. Unlike natural blood vessels, these devices can trigger clotting by activating specific proteins in the blood. Blood clots can obstruct the device, disrupting treatment, or lead to severe complications such as stroke and heart attack.
Doctors often prescribe high doses of blood thinners to prevent clots on these devices, but this approach increases the risk of dangerous bleeding—a trade-off that many patients and clinicians would rather avoid.
The newly developed coating offers a promising alternative. It's engineered to imitate how blood vessels function—encouraging normal blood flow without triggering clot formation. Imagine the coating as a "soft barrier" on a device that attracts a key blood protein but keeps it from activating the clotting process.
By interacting with this protein in a controlled way, the coating prevents it from sparking a cascade of events that lead to clot formation.
In lab and animal studies, the coating demonstrated significant reductions in clot formation on device surfaces, without the use of blood thinners and without affecting the normal clotting functions elsewhere in the body.
One of the most surprising insights was that controlling the interaction between the coating and specific blood proteins could prevent clotting without disrupting the body's natural balance. This shows us that mimicking the body's own mechanisms, rather than simply repelling blood components, is key to truly biocompatible device design.
The innovation comes as demand for blood-contacting devices continues to rise.
Additionally, the team is interested in understanding whether this approach could eventually be adapted to address other blood-related complications, such as inflammation or infection, in long-term medical implants.
Antithrombotic coating with sheltered positive charges prevents contact activation by controlling factor XII–biointerface binding, Nature Materials (2024). DOI: 10.1038/s41563-024-02046-0
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'Moonlighting' enzymes may lead to new cancer therapies
Researchers at the Center for Genomic Regulation (CRG) reveal that metabolic enzymes known for their roles in energy production and nucleotide synthesis are taking on unexpected "second jobs" within the nucleus, orchestrating critical functions like cell division and DNA repair.
The discovery, reported in two separate research papers in Nature Communications, not only challenges longstanding biological paradigms in cellular biology but also opens new avenues for cancer therapies, particularly against aggressive tumors like triple-negative breast cancer (TNBC).
For decades, biology textbooks have neatly compartmentalized cellular functions. Mitochondria are the powerhouses of the cell, the cytoplasm is a bustling factory floor for protein synthesis, and the nucleus a custodian of genetic information. However, scientists have now discovered that the boundaries between these cellular compartments are less defined than previously thought.
Metabolic enzymes are moonlighting outside of their traditional neighborhood. There's an overlap in the skillset, but they're doing entirely different jobs for entirely different purposes. Surprisingly, their secondary roles in the nucleus are just as critical as their primary metabolic functions.
In one of the studies, researchers focused on the metabolic enzyme MTHFD2. Traditionally, MTHFD2 is found in the mitochondria, where it plays a key role in synthesizing the building blocks of life and contributing to cell growth. Others research work reveals that MTHFD2 also moonlights within the nucleus, where it plays a pivotal role in ensuring proper cell division.
The study is the first to demonstrate that the nucleus relies on metabolic pathways to maintain the integrity and stability of the human genome. The nucleus isn't just a passive storage space for DNA; it has its own metabolic needs and processes.
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In the second study, researchers turned their attention to triple-negative breast cancer, the most aggressive type of breast cancer there is. The disease is responsible for around one in eight breast cancer diagnoses and amounts to roughly 200,000 new cases each year worldwide.
Usually, excessive DNA damage triggers cell death. However, TNBC has a propensity to accumulate DNA damage without consequence, making it resilient to conventional treatments. The study helps partly explain why: the metabolic enzyme IMPDH2 relocates to the nucleus of TNBC cells to assist in DNA repair processes.
IMPDH2 acts like a mechanic in the cell's nucleus, controlling the DNA damage response that would otherwise kill the cancer cell.
By experimentally manipulating IMPDH2 levels, the team found they could tip the balance. Increasing IMPDH2 within the nucleus overwhelmed the cancer cells' repair machinery, causing cells to self-destruct.
It's like overloading a sinking ship with more water—eventually, it sinks faster. Their approach effectively forces TNBC cells to succumb to the very DNA damage they are typically resilient to.
The study can also lead to new ways of monitoring cancer. The research on IMPDH2 also studied its interaction with PARP1, a protein already targeted by existing cancer drugs. IMPDH2 could serve as a biomarker to predict which tumors will respond to PARP1 inhibitors.
Both studies contribute to an emerging field of therapies targeting cancer by exploiting its metabolic vulnerabilities.
Nuclear localization of MTHFD2 is required for correct mitosis progression, Nature Communications (2024). DOI: 10.1038/s41467-024-51847-z
Nuclear IMPDH2 controls the DNA damage response by modulating PARP1 activity, Nature Communications (2024). DOI: 10.1038/s41467-024-53877-z
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DNA packaging directly affects how fast DNA is copied in cells, scientists discover
Researchers have found that the way DNA is packaged in cells can directly impact how fast DNA itself is copied during cell division. They discovered that DNA packaging sends signals through an unusual pathway, affecting the cell's ability to divide and grow.
This opens up new doors to study how the copying of the DNA and its packaging are linked. These findings, published in Molecular Cell, may help scientists to find therapies and medicines for diseases such as cancer in the future.
Every day, our cells divide. Each time they need to copy both their DNA and the structure in which the DNA is packed. This packaging, called chromatin, acts as a guide. It tells the cell how, where and when to 'read' and use the information in the DNA. It is important that both the DNA and its chromatin are copied accurately to ensure young and healthy cells. Problems with this process are often seen in diseases like cancer.
The copying of chromatin has a direct effect on the mechanisms that copy DNA itself. If there is a problem with DNA packaging, the cell quickly senses this issue. But instead of triggering a typical stress response, the cell responds by slowing down its cycle of growth and division, without stopping it completely. The slower cycle still allows the cell to divide, but the new cells often struggle to continue to grow, preventing them from dividing again.
So, these mechanisms, which copy DNA and its packaging, are closely connected to cell growth. This discovery paves the way for new studies on these pathways and how DNA packaging can control cell growth. In the future, this knowledge could help to find new treatments for diseases like cancer.
Acute multi-level response to defective de novo chromatin assembly in S-phase, Molecular Cell (2024). DOI: 10.1016/j.molcel.2024.10.023. www.cell.com/molecular-cell/fu … 1097-2765(24)00863-3
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'Drowning' and 'dying' mangrove forests in Maldives signal global coastal threat, say researchers
Researchers have found evidence that mangrove forests—which protect tropical and subtropical coastlines—are drowning in the Maldives.
Their findings, published 12 November in Scientific Reports,
The research team, led by Northumbria University, warn that the findings have implications not only for the Maldives, but also for other island nations and coastal ecosystems around the world.
In 2020, more than a quarter of the Maldivian islands containing mangrove forests saw their trees experiencing a gradual deterioration before dying, a condition known as dieback.
In 2020, more than a quarter of the Maldivian islands containing mangrove forests saw their trees experiencing a gradual deterioration before dying, a condition known as dieback.
Satellite imagery of both inhabited and uninhabited islands revealed the severity of this issue, showing that some islands lost over half of their mangrove cover.
Mangroves play an essential role in protecting coastal regions by acting as natural barriers against storms, erosion and flooding. As biodiversity hotspots, they are vital nurseries for marine species such as crabs, prawns and fish making them crucial for food security and livelihoods in many coastal communities. They also provide valuable resources such as construction materials for housing.
Researchers combined evidence from sea level, climate data and remote sensing with field observations of sediment geochemistry and dendrology to investigate the mangrove dieback.
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Their analysis of mangrove wood revealed that the dead trees showed greater signs of salinity stress compared to living trees.
This stress indicates that the roots of the trees were struggling to cope with increased salt levels, which was a key factor in their eventual death.
The researchers found that sea levels around the Maldives rose at an accelerated rate of over 30mm per year between 2017 to 2020. Towards the end of this period, an unusually intense climate phenomenon known as the Indian Ocean Dipole occurred. This caused warmer sea surface temperatures and an increase in sea level in the Western Indian Ocean.
Although mangroves naturally build up their own sediment, allowing them to adapt to gradually rising seas, this rate of sea level rise was too fast for the mangroves to keep pace.
As tidal movements are more limited in the basin areas where many mangrove forests grow, the rising sea level meant that seawater effectively flooded the forests. This lack of tidal movement and flooding prevented the mangroves from building the sediment they needed to stay above water. They eventually lost their resilience and died off by drowning.
As the mangroves' build-up of sediment slowed down due to the pace of the rising sea level, the soil salinity increased beyond what even these salt-tolerant trees could handle. Essentially, the mangroves were drowning.
The extreme magnitude of dieback seen in the Maldives is a vivid illustration of how climate change may push natural systems past their limits, with cascading consequences for both nature and people.
Carruthers, L. et al. Sea-level rise and extreme Indian Ocean Dipole explain mangrove dieback in the Maldives, Scientific Reports (2024). DOI: 10.1038/s41598-024-73776-z
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Plastic that dissolves in water
At a time when synthetic plastic has polluted nearly every corner of the globe and appeared in food and in the human body, researchers have developed a new plastic that dissolves in water.
The kind of impact that human-made materials are making on the living world is resulting in climate change, pollution and more. One of the ways that we are able to address this is to make materials sustainable and also make materials which are smart or intelligent.
This new bioplastic MECHS—an acronym for Mechanical Engineered Living Materials with Compostability, Healability and Scalability is one such effort.
The researchers presented their discovery in a paper published in the journal Nature Communications.
The study showcases the researchers' most recent work with engineered living materials, which use living cells to produce functional materials.
First, the nature-inspired solutions can be made to regenerate, regulate and/or respond to external stimuli such as light and can even heal itself.
Secondly, unlike the plastics that are polluting the planet and our bodies, the materials are biodegradable in water and even the compost bin.
But while engineered living materials have been manipulated to adhere, catalyze and remediate, and be either soft or stiff, such materials have not been scalable for widespread production.
That's where MECHS comes in.
MECHS consists of engineered E. coli bacteria with a fiber matrix to create a paper- or film-like material.
The fibers give MECHS several desirable properties. It means that MECHS can stretch like plastic wrap, can be genetically engineered by adding proteins or peptides to make it more or less stiff. And it is healable—a small amount of water disentangles the fibers, which then re-entangle as the MECHS dries.
Meanwhile, a lot of water or a trip to a compost bin causes the material to dissolve. In fact, it dissolves much faster than other biodegradable plastics, the researchers found.
Finally, the material can also be easily mass produced in a process similar to paper manufacturing.
Avinash Manjula-Basavanna et al, Mechanically Tunable, Compostable, Healable and Scalable Engineered Living Materials, Nature Communications (2024). DOI: 10.1038/s41467-024-53052-4
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Young coral use metabolic tricks to resist bleaching, research reveals
Coral larvae reduce their metabolism and increase nitrogen uptake to resist bleaching at high temperatures, according to a study published November 12 in the open-access journal PLOS Biology.
High ocean temperatures cause coral bleaching, which results from the disruption of the relationship between corals and their symbiotic algae, an increasing concern as global temperatures rise. However, relatively little research has examined the effects of high temperatures during the early life stages of corals.
In this study, researchers exposed coral larvae to high temperatures at the Hawai'i Institute of Marine Biology. For three days during their first week of development, the larvae and their algal symbionts were treated to temperatures 2.5 degrees Celsius above ambient temperature, similar to expected changes in seawater due to climate change.
The coral larvae showed no signs of bleaching in the heated water, and they were able to maintain rates of algal photosynthesis and the supply of carbon-based nutrition from the algae to the host. However, there was a 19% reduction in coral metabolism, as well as increased uptake and storage of nitrogen by the coral, both of which are apparent strategies that improve coral survival.
Reduced metabolism allows the coral to conserve energy and resources, also seen in adult corals during bleaching. The change in nitrogen cycling seems to be an adaptation by the coral to limit the amount of nitrogen available to the algae, thus preventing algal overgrowth and the destabilization of the coral-algae relationship.
It remains unclear how effective these strategies are at higher temperatures and for longer durations. Further research into the details and limitations of coral reaction to high temperatures will provide crucial knowledge for predicting coral response and protecting coral reefs as global temperatures continue to rise.
The authors add, "This research reveals that coral larvae must invest in their nutritional partnership with algae to withstand stress, offering key insights into strategies to avoid bleaching in earliest life stages of corals."
Huffmyer AS, et al. Coral larvae increase nitrogen assimilation to stabilize algal symbiosis and combat bleaching under increased temperature, PLOS Biology (2024). DOI: 10.1371/journal.pbio.3002875
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Study challenges popular belief that children are quicker at picking up new motor skills than adults
Contrary to popular belief, children aren't better at learning new skills than adults. Indeed, young adults seem to learn faster than kids—but also tend to forget more quickly. Here, better sleep seems to advantage children. This is the conclusion of a new study.
It's widely believed that children learn new motor skills faster than adults, whether it's mastering slopes or skateparks, learning new languages, doing cartwheels or picking up new dance moves from TikTok.
"There's an assumption in popular science literature and various textbooks that children in a certain age range—from roughly the age of 8 until puberty—are better at learning new skills than adults. This is often described as a 'golden age for motor skills learning.'But there's no actual physiological basis for this so-called golden age.
The popular notion of a pre-pubescent motor learning peak prompted the researchers to investigate how age-related differences in our central nervous system affect motor skill learning. Their findings are now published in Developmental Science.
In the study, the researchers tested the motor learning abilities of 132 participants from four age groups: 8–10 years, 12–14 years, 16–18 years, and 20–30 years. In a lab setting, participants practiced moving a cursor on a computer screen with fast and precise finger movements.
Participant performance was measured immediately after being introduced to the task (as a baseline), during the training session, and again 24 hours later.During the training session itself, both the 16- to 18-year-olds and 20- to 30-year-olds improved their skills significantly more than the 8- to 10-year-olds.
"So it appears that both teenagers and younger adults are better equipped to quickly acquire new skills compared to children, who showed smaller and slower improvements. At least when it comes to short-term learning and motor skills which this study investigated,
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While the researchers cannot pinpoint the exact reasons for why the adults learn faster, they have a few theories.
"The results demonstrate that the older the participants are, the more skillful they become during the early stages of training. This suggests that they get more out of the task introduction. We suspect that cognitive development and an increased ability to process information play a role—meaning adults may have more experience receiving instructions and translating them into action.
"The difference may also be because the fully developed nervous system of an adult provides better structural conditions for learning. In other words, after many years of schooling, adults may be more experienced learners and thereby more efficient at learning new things.
The picture changes when it comes to retention.
"When the researchers looked at what happens from the end of training until the participants return the next day, the dynamic reverses. While the youngest participants actually improve overnight, adults lose some of their ability to perform. This means the youngest ones are better at consolidating and reinforcing their memory after they've practiced,
According to the researchers, this suggests that sleep benefits children's learning and memory more. But other factors could also be at play. For example, older children and adults typically sleep less and have more "competing" activities throughout the day. Memory-consolidation processes in the nervous system continue for hours after the training ends.
When a math class ends, the brain keeps working on what was taught, and in doing so, reinforces memory. Sleep is known to aid consolidation. But engaging in other activities in the hours after—especially those that involve learning—can interfere with memory processes and the consolidation of what was just learned.
While the overall learning outcome doesn't vary drastically across age groups, the study does show that the learning process differs significantly depending on age, with underlying mechanisms influenced by the maturity of one's central nervous system.
Mikkel Malling Beck et al, Distinct mechanisms for online and offline motor skill learning across human development, Developmental Science (2024). DOI: 10.1111/desc.13536
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Using personal care products during and after pregnancy can increase exposure to toxic chemicals
For people who are pregnant or nursing, more use of personal care products is associated with higher detectable levels of synthetic chemicals known to have adverse health effects, a new study by researchers has found.
The study, published in Environment International, found that using personal care products like nail polish, makeup and hair dye while pregnant or lactating is associated with significantly higher levels of per- and polyfluoroalkyl substances, known as PFAS, in blood plasma and breast milk.
While PFAS are ubiquitous in the environment, this study indicates that personal care products are a modifiable source of PFAS. People who are concerned about their level of exposure to these chemicals during pregnancy or while breastfeeding may benefit from cutting back on personal care products during those times.
PFAS are synthetic chemicals that have been used in consumer products and industrial settings since the 1950s due to their ability to resist oil, water and heat. The study notes that PFAS have been associated with a range of adverse health effects, including liver disease, cardiometabolic and cardiovascular issues, and various cancers.
While several studies have detected these chemicals in personal care products directly, few have evaluated whether using these products impacts internal PFAS concentrations.
This is important, she added, because exposure to PFAS during pregnancy could contribute to adverse birth outcomes such as decreased birth weight, preterm birth, some neurodevelopmental disorders and diminished vaccine response in children.
The analyzed data from the Maternal-Infant Research on Environmental Chemicals Study, which enrolled 2,001 pregnant people from 10 cities across Canada between 2008 and 2011. The researchers evaluated the contribution of the use of personal care products on PFAS concentrations in prenatal plasma (6 to 13 weeks gestation) and human milk (2 to 10 weeks postpartum). Participants reported frequency of use across eight product categories during the first and third pregnancy trimesters, one to two days postpartum, and 2 to 10 weeks postpartum.
In first-trimester pregnant people, the researchers found that higher use of nail care products, fragrances, makeup, hair dyes and hair sprays or gels was associated with higher plasma PFAS concentrations. Similar results were observed for third-trimester personal care product use and breast-milk PFAS concentrations at 2 to 10 weeks postpartum.
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For instance, participants who wore makeup daily in the first and third trimesters had 14% and 17% higher plasma and breast-milk PFAS concentrations, respectively, compared to people who did not wear makeup every day. In addition, the researchers found that people using colored-permanent dye one to two days postpartum had higher PFAS levels (16% to 18% increases compared to never using them) in human milk concentrations.
The researchers noted that the study examined only four types of PFAS among thousands that are used in industry and commerce. Thus, the study likely underestimated the extent of exposure to all PFAS from these products during pregnancy.
Amber M Hall et al, Personal care product use and per- and polyfluoroalkyl substances in pregnant and lactating people in the Maternal-Infant Research on Environmental Chemicals study, Environment International (2024). DOI: 10.1016/j.envint.2024.109094
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Self-treatment sparks ethics debate
Virologist Beata Halassy treated her own breast cancer by injecting the tumour with viruses she grew in the lab. In 2020, Halassy discovered she had a second recurrence of breast cancer at the site of a previous mastectomy. To avoid another bout of chemotherapy, she self-administered experimental oncolytic virotherapy. Halassy has now been cancer-free for four years. Her decision to treat herself, and subsequently publish a report detailing the process, has sparked discussion about the ethics of self-experimentation and the risk it might encourage others to try unproven treatments. “It took a brave editor to publish the report,” says Halassy.
Nature |
Reference: https://www.mdpi.com/2076-393X/12/9/958
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Oropouche virus transmission to unborn child confirmed
The first confirmed case of vertical transmission of Oropouche virus (OROV) has been reported by 23 researchers from eight distinct institutions in Brazil.
OROV, a zoonotic arbovirus, was first isolated from the blood of a charcoal worker with a high fever in 1955 on the Caribbean island of Trinidad. Outbreaks have typically occurred south of the Amazon, isolated within Amazonian villages.
In 2024, OROV infections were detected in previously non-endemic areas across all five Brazilian regions. These expansions into previously unaffected regions involve new virus variants emerging from genetic reassortment.
In a letter to the editor titled "A Case of Vertical Transmission of Oropouche Virus in Brazil," published October 30, 2024, in the New England Journal of Medicine, researchers report on a case from Ceará, a state historically free from OROV, finding its first infection case through active laboratory surveillance.
Subsequent investigations identified 171 cases, predominantly in the rural valleys of the Baturité Massif. Agricultural landscapes in this region favor the Culicoides paraensis midge, a small biting fly sometimes referred to as "no-see-ums" due to their tiny size. Culicoides is the primary vector for OROV transmission to humans.
A notable case involved a 40-year-old pregnant woman at 30 weeks gestation who developed fever, chills, muscle aches, and severe headache. Routine prenatal care had previously identified gestational diabetes, managed with metformin, and four routine obstetric ultrasounds.
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On July 27, medical evaluation revealed light vaginal bleeding and dark discharge, with ultrasonography indicating fetal macrosomia.
By August 5, continued symptoms and decreased fetal movements led to the confirmation of fetal demise.
Molecular diagnostics confirmed acute OROV infection, ruling out dengue, Zika, chikungunya, and Mayaro viruses. Minimal invasive tissue sampling of the stillborn infant revealed OROV RNA in multiple fetal tissues, establishing vertical transmission.
Phylogenetic analysis using maximum-likelihood inference positioned the virus within the OROVBR-2019-2024 lineage, consistent with strains from the ongoing outbreak. These findings link the stillbirth directly to the current OROV spread in Brazil, highlighting the virus's potential risks during pregnancy.
The report should sound the alarm for health care providers to consider OROV infection in pregnant women presenting with fever and related symptoms in endemic or emerging regions.
Carlos Garcia Filho et al, A Case of Vertical Transmission of Oropouche Virus in Brazil, New England Journal of Medicine (2024). DOI: 10.1056/NEJMc2412812
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Redefining net zero will not stop global warming, scientists say
This is really absurd. Governments and countries are trying to evade climate goals to stop global warming.
In a study, led by the University of Oxford's Department of Physics and published 18 November in Nature, an international group of authors who developed the science behind net zero demonstrate that relying on 'natural carbon sinks' like forests and oceans to offset ongoing CO2 emissions from fossil fuel use will not actually stop global warming.
The science of net zero, developed over 15 years ago, does not include these natural carbon sinks in the definition of net human-induced CO2 emissions.
Natural sinks play a vital role in moderating the impact of current emissions and draw down atmospheric CO2 concentrations after the date of net zero, stabilizing global temperatures. Yet governments and corporations are increasingly turning to them to offset emissions, rather than reducing fossil fuel use or developing more permanent CO2 disposal options.
Emissions accounting rules encourage this by creating an apparent equivalence between fossil fuel emissions and drawdown of CO2 by some natural carbon sinks, meaning a country could appear to have 'achieved net zero' while still contributing to ongoing warming.
The authors call on governments and corporations to clarify how much they are counting on natural carbon sinks to meet their climate goals, as well as recognizing the need for "Geological Net Zero."
Geological Net Zero means balancing flows of carbon into and out of the solid Earth, with one ton of CO2 committed to geological storage for every ton still generated by any continued fossil fuel use. Given the cost and challenges of permanent geological CO2 storage, achieving Geological Net Zero will require a substantial reduction in fossil fuel use.
The authors stress the importance of protecting and maintaining natural carbon sinks while accepting that doing so cannot compensate for ongoing fossil fuel use. Total historical CO2 emissions determine how much a country or company has contributed to the global need for ongoing natural carbon sinks.
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Dr. Krishna Kumari Challa
We are already counting on forests and oceans to mop up our past emissions, most of which came from burning stuff we dug out of the ground. We can't expect them to compensate for future emissions as well. By mid-century, any carbon that still comes out of the ground will have to go back down, to permanent storage. That's Geological Net Zero.
Countries report both emissions and removals, but using all removals in climate targets is a recipe for continued warming. Natural carbon sinks currently clean up around half our annual emissions for free, but this ecosystem service must be kept separate from the fossil emissions driving climate change. Relabeling things will not stop global warming, say the scientists.
They stress that: It is a common assumption that removing carbon from the atmosphere to offset burning of fossil fuels is as effective as not burning fossil fuels in the first place. It is not.
Offsetting continued fossil fuel use with carbon removal will not be effective if the removal is already being counted on as part of the natural carbon cycle and if the carbon is not permanently stored. Unless we can increase transparency in national Greenhouse gas reporting and target setting, offsets will become part of the problem instead of part of the solution.
Land is limited, we rely on it for food, nature, biodiversity, leisure, water storage, and so on. It cannot offset more than a portion of fossil emissions even now, probably less in future, with worsening pressures on the biosphere such as population increase, fires, and drought.
"Giving carbon credits for natural processes that are happening anyway undermines trust in the whole idea of offsetting. We have to urgently protect natural carbon sinks, but there are more scientifically credible and equitable ways of doing this than relying on carbon offset markets."
Is anybody listening?
Myles Allen, Geological Net Zero and the need for disaggregated accounting for carbon sinks, Nature (2024). DOI: 10.1038/s41586-024-08326-8. www.nature.com/articles/s41586-024-08326-8
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Dr. Krishna Kumari Challa
Extreme heat weakens land's power to absorb carbon, analysis finds
A new European Space Agency-backed study shows that the extreme heat waves of 2023, which fueled huge wildfires and severe droughts, also undermined the land's capacity to soak up atmospheric carbon. This diminished carbon uptake drove atmospheric carbon dioxide levels to new highs, intensifying concerns about accelerating climate change.
Measurements from Hawaii's Mauna Loa Observatory showed that atmospheric carbon concentrations surged by 86% in 2023 compared to the previous year, marking a record high since tracking began in 1958.
Despite this sharp increase, fossil fuel emissions only rose by about 0.6%, suggesting that other factors, such as weakened carbon absorption by natural ecosystems, may have driven the spike.
An international team of scientists analyzed global vegetation models and satellite data to investigate the underlying causes and deliver an expedited carbon budget report for 2023.
Typically, land absorbs roughly one-third of human-generated carbon dioxide emissions. However, the team's research published in National Science Review reveals that in 2023, this capacity fell to just one-fifth of its usual level, marking the weakest land carbon sink performance in two decades.
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Dr. Krishna Kumari Challa
Widespread wildfires across Canada and droughts in the Amazon in 2023 released about the same amount of carbon to the atmosphere as North America's total fossil fuel emissions, underscoring the severe impact of climate change on natural ecosystems.
The Amazon—one of the world's most crucial carbon sinks—is showing signs of long-term strain, with some regions shifting from absorbing carbon to becoming net sources of carbon emissions.
The researchers suggest that the declining capacity of Earth's land ecosystems to absorb carbon dioxide may indicate that these natural carbon sinks are nearing their limits and no longer able to provide the mitigation service they have historically offered by absorbing half of human-induced carbon dioxide emissions.
Consequently, achieving safe global warming limits will require even more ambitious emission reductions than previously anticipated, the scientists say.
The study also highlights that current climate models might be underestimating the rapid pace and impact of extreme events, such as droughts and fires, on the degradation of these crucial carbon reservoirs.
Piyu Ke et al, Low latency carbon budget analysis reveals a large decline of the land carbon sink in 2023, National Science Review (2024). DOI: 10.1093/nsr/nwae367
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Dr. Krishna Kumari Challa
Magenta aurora over Japan
Why May 2024's aurora appeared a magenta color over Japan?
Around the world, the historic geomagnetic superstorm of late spring 2024 inspired millions of non-scientists around the world—many armed with highly sensitive smartphone cameras—to take a fantastic, unprecedented number of images of the aurora it produced.
In Japan, this widespread popular uptake of what is now quite advanced imaging technology (even if it is kept in everyone's pocket) proved to be a tremendous boon for atmospheric physicists and other scientists specializing in "space weather." It allowed them to discover why the Northern Lights over Japan appeared as a mysterious magenta color this time instead of the typical red that is observed when aurorae are visible over that country.
In early May this year, one of the most extreme geomagnetic storms in the history of recording such events hit the Earth's atmosphere. This great "storm" in space, composed of ionized particles, is what produces the aurora borealis, or Northern Lights, in the northern hemisphere and the aurora australis, or Southern Lights, in the southern hemisphere.This time, however, the storm was so strong—the ninth most severe storm in the 110-year history of Japan's Kakioka Magnetic Observatory, one of the oldest geomagnetic stations in the world—that the polar lights could be photographed at much lower latitudes than normal.
Part 1
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Dr. Krishna Kumari Challa
In Japan, space weather researchers took advantage of ordinary people taking pictures of the aurora with their smartphones to organize one of the densest citizen science observation efforts anywhere, despite being a low-latitude country where the aurora was somewhat fainter than in places like Canada or northern Europe.
The different colors of an aurora come from the emission of light from different atoms and molecules in the atmosphere when they are bombarded by the particles from space. The dramatic green hue seen in many photographs of the polar lights comes from atomic oxygen (single atoms of oxygen rather than molecular oxygen, or two oxygen atoms bound together) at the lower altitudes within the atmosphere that are visible to people. (The human eye is also just very sensitive to this color). At even lower altitudes, where atomic oxygen is less common, blue is more visible, and this comes from the greater presence of nitrogen.
At the very highest altitudes in the atmosphere, however, there is a lower concentration of atoms of any kind. The fewer collisions there result in a perception by humans of the excited atomic oxygen atoms as the color red. This is why the upper parts of the aurora curtains can appear as green fading into a scarlet hue.
At low latitudes, as in Japan, normally there is no green at all, only red because only the upper part of the aurora can be seen above the horizon.
"Yet this time, weirdly, the images revealed a very clear and dominant magenta hue to the aurora 'curtains' over Japan, not red.
To solve the mystery, the researchers quickly took to social media to encourage people to observe and report their sightings of the auroras, as well as to input data into a questionnaire asking about observation locations, time, elevation angles and other details, allowing researchers to analyze the auroras' characteristics in unprecedented detail.
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Dr. Krishna Kumari Challa
The effort resulted in an impressive 775 grassroots submissions, which the researchers then combined with satellite observations and advanced modeling techniques to explore the conditions that had led to the magenta aurora.
The elevation data from these citizen scientists proved to be particularly useful. The researchers used elevation angles to calculate the position of the aurora over time, and found that it was often a surprisingly high altitude of roughly 1,000 km above sea level—which should thus drive a red appearance. But on top of this, the time and season of year meant the atmosphere was more "preheated" ahead of the aurora, in turn driving an upwelling of ionized molecular nitrogen—what is usually responsible for a blue hue.
"Blue plus red makes us see magenta.
And the magenta was made all the more visible and vibrant by the sheer volume of solar activity, even though, ironically, the preheating would also have worked to reduce the peak brightness of the aurora."
Better understanding of magnetic storms goes beyond explaining why humans see the pretty colors of aurorae; these storms can have profound, negative impacts on satellite operations, GPS systems, power grids and even the safety of passengers and crews aboard high-altitude flights.
Ryuho Kataoka et al, Extended magenta aurora as revealed by citizen science, Scientific Reports (2024). DOI: 10.1038/s41598-024-75184-9
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Dr. Krishna Kumari Challa
Confinement may affect how we smell and feel about food
New research found confined and isolating environments changed the way people smelled and responded emotionally to certain food aromas.
The team in this study compared 44 people's emotional responses and perception of eight food aromas in two environmental scenarios: sitting in reclined chairs that mimic astronauts' posture in microgravity; and then in the confined setting of the International Space Station (ISS), which was simulated for participants with virtual reality goggles.The aromas the team tested on participants were vanilla, almond, lemon, lemon myrtle, eucalyptus, peppermint, vinegar and lemongrass.
The research, published in Food Research International, builds on previous work by the team and aims to help explain why astronauts report meals taste different in space and struggle to eat their normal nutritional intake over long missions, which has been reported in the news recently.
The study has broader implications for further research to improve the diets of isolated people, including nursing home residents, by personalizing aromas to enhance the flavor of their food.
Part 1
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Dr. Krishna Kumari Challa
Lemongrass consists of a more floral and earthy aroma, while the other aromas are pungent, spicy or sweet. This difference in profile may explain why lemongrass seemed less intense in the VR setting compared to the microgravity posture.
In an Earth-like setting, eating was often social, but eating in space on long missions can feel quite different.
Pilot studies [published open-access in the journal Science Talks] show that spending 10 minutes in VR can induce feelings of confinement, highlighting VR's effectiveness over other methods such as immersive screens.
"Results indicate that a remote, confined environment such as the ISS and a significant variation in personal sensitivities influence aroma perception, making certain foods smell strange.
Space studies often emphasized microgravity as the main contributing factor to food's different taste, but the team's findings underscored the impact of confined and isolated environments.
This research opens possibilities for personalized meal plans for astronauts and individuals living alone on Earth, showcasing VR's potential to explore variations in eating when stressed.
In the VR setting, participants reporting positive emotions perceived stronger aromas.This link between stress and vinegar may help explain why astronauts like to eat certain foods in microgravity that they don't normally enjoy on Earth.
Food odour perception and affective response in virtual spacecraft and microgravity body posture (1-G) – potential ground-based simulations, Food Research International (2024).
Julia Low et al, Development of a virtual reality spacecraft environment as a ground-based analog for collecting space food sensory data ('Food in Space'), Science Talks (2024). DOI: 10.1016/j.sctalk.2024.100391
Alicia Tran et al, Exploring fundamentals of immersive environment setups on food sensory perception in space contexts, Science Talks (2024). DOI: 10.1016/j.sctalk.2024.100403
Part 2
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Dr. Krishna Kumari Challa
Scientists transform blood into regenerative materials, paving the way for personalized, 3D-printed implants
Scientists have created a new 'biocooperative' material based on blood, which has been shown to successfully repair bones, paving the way for personalized regenerative blood products that could be used as effective therapies to treat injury and disease.
Researchers have used peptide molecules that can guide key processes taking place during the natural healing of tissues to create living materials that enhance tissue regeneration. The research is published in Advanced Materials.
Most of our body tissues have evolved to regenerate ruptures or fractures with remarkable efficacy, as long as these are small in size. This healing process is highly complex. The initial stages rely on liquid blood forming the solid regenerative hematoma (RH), a rich and living microenvironment comprising key cells, macromolecules, and factors that orchestrate regeneration.
The team developed a self-assembling methodology where synthetic peptides are mixed with whole blood taken from the patient to create a material that harnesses key molecules, cells, and mechanisms of the natural healing process. In this way, it was possible to engineer regenerative materials capable of not only mimicking the natural RH, but also enhancing its structural and functional properties.
These materials can be easily assembled, manipulated, and even 3D printed while maintaining normal functions of the natural RH, such as normal platelet behavior, generation of growth factors, and recruitment of relevant cells important for healing. With this method, the team has shown the capacity to successfully repair bone in animal models using the animal's own blood.
Soraya Padilla‐Lopategui et al, Biocooperative Regenerative Materials by Harnessing Blood‐Clotting and Peptide Self‐Assembly, Advanced Materials (2024). DOI: 10.1002/adma.202407156
on Tuesday
Dr. Krishna Kumari Challa
Scientists convert plastics into soaps and detergents
Researchers found a way to convert certain plastics into soaps, detergents, lubricants, and other products.
The process has two steps. It first involved using thermolysis, or breaking down a substance—in this case, plastic—by using heat. Plastic placed in a reactor built by the research team and heated to between 650 and 750 degrees Fahrenheit broke down into chemical compounds, leaving a mixture of oil, gas, and residual solids.
The key to this first step was breaking down the polypropylene and polyethylene molecules that make up plastic within a certain carbon range, and Liu and his team were able to accomplish this.
The residual solids left behind were minimal, and the gas could be captured and used as fuel. The oil, though, was the product of the most interest here.
They were also was able to functionalize, or change the chemistry, of the oil into molecules to be converted into soaps, detergents, lubricants, and other products.
These materials are stable. You could use them to wash your hands and dishes. The researchers have used them to wash their lab glassware in the laboratory.
The process, which took less than a day, led to almost zero air pollution output, thus offering clues to a desperately needed solution to a global problem.
Nuwayo Eric Munyaneza et al, Chain-length-controllable upcycling of polyolefins to sulfate detergents, Nature Sustainability (2024). DOI: 10.1038/s41893-024-01464-x
on Tuesday
Dr. Krishna Kumari Challa
Researchers uncover how blood pressure drugs harm kidneys
Commonly prescribed drugs used to treat high blood pressure have been shown to, over time, wreck the kidneys' ability to filter and purify blood. How does this happen?
Manako Yamaguchi et al, Transformation of the Kidney into a Pathological Neuro-Immune-Endocrine Organ, Circulation Research (2024). DOI: 10.1161/CIRCRESAHA.124.325305
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Dr. Krishna Kumari Challa
High exposure to everyday chemicals linked to asthma risk in children
A new study by researchers at Kumamoto University sheds light on a potential link between exposure to certain everyday chemicals during pregnancy and the development of asthma in children. The study analyzed data from over 3,500 mother-child pairs as part of the Japan Environment and Children's Study (JECS), a large-scale nationwide research project.
researchers measured 24 types of phenols in urine samples collected from pregnant women. They then tracked the health of their children until the age of four.
The study is published in the journal Environmental Pollution.
Shohei Kuraoka et al, Association of phenol exposure during pregnancy and asthma development in children: The Japan Environment and Children's study, Environmental Pollution (2024). DOI: 10.1016/j.envpol.2024.124801
yesterday
Dr. Krishna Kumari Challa
By exerting 'crowd control' over mouse cells, scientists make progress towards engineering tissues
Genes aren't the sole driver instructing cells to build multicellular structures, tissues, and organs. In a paper published in Nature Communications, scientists characterize the influence of another important developmental driver: cell density, or how loosely or tightly cells are packed into a given space.
In both computational models and laboratory experiments, the team of scientists used cell density as an effective tool for controlling how mouse cells pattern themselves into complex structures.
This paper represents progress towards their big picture goal of engineering synthetic tissues. Synthetic tissues could have endless medical applications, ranging from testing potential drugs or therapies to providing grafts or transplants for patients.
The study used two types of mouse cells—connective tissue cells and stem cells—engineered to carry a synthetic cellular communication system or "genetic circuit. This circuit is based on something they developed called "synNotch," which is a protein that scientists genetically engineer into a cell to serve as a "sensor."
Located on a cell's surface, this protein-based sensor recognizes an external signal that triggers the cell to respond—usually by turning on a user-defined gene.
For this particular series of experiments, the scientists used synNotch to turn on a circuit that includes green fluorescence and a way to propagate the signal further—although it could be used to turn on any gene. The fluorescence made it easy to observe cells as they formed patterns. For example, in a field of cells, scientists could create a pattern of green fluorescent rings emanating from a central point.
While conducting these experiments, the scientists noticed that genetically identical cells did not always produce the same patterns.
So that was puzzling at the beginning. When the researchers looked at it more carefully, they started seeing that there was a gradient of cell density that seemed to correlate with differences in patterning.
Part 1
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Dr. Krishna Kumari Challa
Nature Communications (2024). DOI: 10.1038/s41467-024-53078-8
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Dr. Krishna Kumari Challa
Research reveals even single-cell organisms exhibit habituation, a simple form of learning
Up until recently, habituation -- a simple form of learning -- was deemed the exclusive domain of complex organisms with brains and nervous systems, such as worms, insects, birds, and mammals. But a new study offers compelling evidence that even tiny single-cell creatures such as ciliates and amoebae, as well as the cells in our own bodies, could exhibit habituation akin to that seen in more complex organisms with brains.
A dog learns to sit on command, a person hears and eventually tunes out the hum of a washing machine while reading … The capacity to learn and adapt is central to evolution and, indeed, survival.
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Dr. Krishna Kumari Challa
Lina Eckert, Maria Sol Vidal-Saez, Ziyuan Zhao, Jordi Garcia-Ojalvo, Rosa Martinez-Corral, Jeremy Gunawardena. Biochemically plausible models of habituation for single-cell learning. Current Biology, 2024; DOI: 10.1016/j.cub.2024.10.041
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Dr. Krishna Kumari Challa
Astronauts found to process some tasks slower in space, but no signs of permanent cognitive decline
A stay in space exerts extreme pressures on the human body. Astronauts' bodies and brains are impacted by radiation, altered gravity, challenging working conditions, and sleep loss—all of which could compromise cognitive functioning. At the same time, they are required to perform complex tasks, and minor mistakes can have devastating consequences.
Working with 25 astronauts who spent an average of six months on the International Space Station (ISS), researchers have examined changes in a wide range of cognitive performance domains. This dataset makes up the largest sample of cognitive performance data from professional astronauts published to date.
The research shows that there is no evidence of any significant cognitive impairment or neurodegenerative decline in astronauts spending six months on the ISS. Living and working in space was not associated with widespread cognitive impairment that would be suggestive of significant brain damage.
The results showed that responses to tasks assessing processing speed, working memory, and attention were slower than on Earth, but they were no less accurate. These changes, however, did not persist equally long.
Slowed performance on attention, for example, was only observed early during the mission, while slowed performance on processing speed did not return to baseline levels until after the mission ended and the crew were back on Earth.
Overall, astronauts' cognitive performance was stable, and the researchers did not find evidence that would suggest damage to the central nervous system during a six-month space mission.
Cognitive Performance in ISS Astronauts on 6-month Low Earth Orbit Missions, Frontiers in Physiology (2024). DOI: 10.3389/fphys.2024.1451269
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Dr. Krishna Kumari Challa
'Flame-Throwing' Guitar Nebula
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Dr. Krishna Kumari Challa
Ethiopian wolves seen feeding on nectar of red hot poker flowers
Strange things happen in nature!
New findings, published in the journal Ecology, describe a newly documented behavior of Ethiopian wolves (Canis simensis).
Researchers observed Ethiopian wolves foraging for the nectar of the Ethiopian red hot poker (Kniphofia foliosa) flower. Some individuals would visit as many as 30 blooms in a single trip, with multiple wolves from different packs exploiting this resource. There is also some evidence of social learning, with juveniles being brought to the flower fields along with adults.
In doing so, the wolves' muzzles become covered in pollen, which they could potentially transfer from flower to flower as they feed. This novel behavior is perhaps the first known plant-pollinator interaction involving a large predator, as well as the only large meat-eating predator ever to be observed feeding on nectar.
Sandra Lai et al, Canids as pollinators? Nectar foraging by Ethiopian wolves may contribute to the pollination of Kniphofia foliosa, Ecology (2024). DOI: 10.1002/ecy.4470
yesterday
Dr. Krishna Kumari Challa
Scientists discover the molecular composition of potentially deadly venomous fish
New research in FEBS Open Bio reveals insights into the venom of two of the most venomous fish species on Earth: the estuarine stonefish (Synanceia horrida) and the reef stonefish (Synanceia verrucosa), which are typically found in the warm and shallow regions of the Indo-Pacific region, the Persian Gulf, and the Red Sea.
Through multiple analytical techniques, investigators discovered the presence of three neurotransmitters new to stonefish venom, namely gamma-aminobutyric acid (GABA), choline, and 0-acetylcholine.
Although these molecules have been previously found in venoms from other species, such as hornets and spiders, this is the first report of a fish venom that contains GABA, which is capable of modulating cardiovascular function with a range of effects including increased heart rate and low blood pressure.
Characterization of the specific composition of each of these fish species' venom not only provides us with a better understanding of envenomation mechanisms, which are needed for the development of targeted treatments against venom effects, but may also aid in the exploration and development of venom-derived compounds in drug discovery.
Silvia Luiza Saggiomo et al, Interrogating stonefish venom: small molecules present in envenomation caused by Synanceia spp., FEBS Open Bio (2024). DOI: 10.1002/2211-5463.13926
yesterday
Dr. Krishna Kumari Challa
Weight-loss drug found to shrink heart muscle in mice and human cells
Trendy weight-loss drugs making headlines for shrinking waistlines may also be shrinking the human heart and other muscles, according to a new study in JACC: Basic to Translational Science. The authors say the research should serve as a "cautionary tale" about possible long-term health effects of these drugs.
Researchers set out to study why a reported side-effect of the leading weight-loss drug Ozempic is the loss of skeletal muscle.
Ozempic, known medically as semaglutide, was originally designed to help adult patients with type 2 diabetes control their blood sugar. However, this drug—and a host of others in this class of medication—are also being touted for their effectiveness as an anti-obesity medication.
Using mice for the study, the researchers found that heart muscle also decreased in both obese and lean mice. The systemic effect observed in mice was then confirmed in cultured human heart cells.
Matthew D. Martens et al, Semaglutide Reduces Cardiomyocyte Size and Cardiac Mass in Lean and Obese Mice, JACC: Basic to Translational Science (2024). DOI: 10.1016/j.jacbts.2024.07.006
yesterday
Dr. Krishna Kumari Challa
Females sleep less and awaken more frequently than males, which may have broad implications for medical research
Females sleep less, wake up more often and get less restorative sleep than males, according to a new animal study by researchers.
The findings, published in the journal Scientific Reports, shed new light on what may underlie sleep differences in men and women and could have broad implications for biomedical research, which for decades has focused primarily on males.
In humans, men and women exhibit distinct sleep patterns, often attributed to lifestyle factors and caregiving roles. However, these new results suggest that biological factors may play a more substantial role in driving these sleep differences than previously recognized.
Sleep research has exploded in recent years, with thousands of animal studies exploring how insufficient sleep impacts risk of diseases like diabetes, obesity, Alzheimer's and immune disorders—and how such diseases impact sleep.
But many of those results may have been skewed due to a lack of female representation, the study suggests.
The question the female researchers now ask is: Are we creating too much stress for ourselves because we don't sleep as much as our husband or partner and think our sleep is poor when actually that is a normal sleep profile for ourselves?
The authors hope their findings inspire more research into underlying biological differences. More importantly, they hope the study prompts scientists to re-evaluate how they do research and interpret the results.
Grant S. Mannino et al, The importance of including both sexes in preclinical sleep studies and analyses, Scientific Reports (2024). DOI: 10.1038/s41598-024-70996-1
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Dr. Krishna Kumari Challa
Healthy women have cells that resemble breast cancer, study finds
A new study from cancer researchers finds that, in healthy women, some breast cells that otherwise appear normal may contain chromosome abnormalities typically associated with invasive breast cancer. The findings question conventional thinking on the genetic origins of breast cancer, which could influence early cancer detection methods.
The study, published recently in Nature, discovered that at least 3% of normal cells from breast tissue in 49 healthy women contain a gain or loss of chromosomes, a condition known as aneuploidy, and that they expand and accumulate with age. This poses questions for our understanding of "normal" tissues, according to principal investigator of this research.
As researchers continue to develop earlier detection methods using molecular diagnostics along with ductal carcinoma in situ (DCIS) and biopsies, these findings pose a challenge and highlight the potential risk of identifying false positives, as the cells can mistakenly be confused with invasive breast cancer.
A cancer researcher or oncologist seeing the genomic picture of these normal breast tissue cells would classify them as invasive breast cancer.
"We've always been taught that normal cells have 23 pairs of chromosomes, but that appears to be inaccurate because every healthy woman that we analyzed in our study had irregularities, bringing up the very provocative question about when cancer actually occurs", say the researchers.
The study builds upon their previous work on the Human Breast Cell Atlas, which profiled over 714,000 cells to generate a comprehensive genetic map of normal breast tissue at the cellular level.
Yiyun Lin et al, Normal breast tissues harbour rare populations of aneuploid epithelial cells, Nature (2024). DOI: 10.1038/s41586-024-08129-x
yesterday
Dr. Krishna Kumari Challa
This Strange Crystal Has Two Melting Points
In 1896, German chemist Emil Fischer noted something very strange about a molecule named acetaldehyde phenylhydrazone. Identical batches of the crystalline compound appeared to have wildly different melting points.
Some batches, he found, melted at temperatures of around 65 degrees Celsius (149 Fahrenheit). Others at 100 degrees Celsius. It was, in a word, utterly bizarre. No other substance was known to behave this way. Nor should it.
According to the laws of thermodynamics that describe the way the physical world behaves, such a result should be impossible.
More than 120 years after Fischer's original discovery, in 2019, an international team of researchers led by chemist Terry Threfall of the University of Southampton in the UK finally found and published the answer. Fischer (who went on to win a 1902 Nobel prize for other work, so he was clearly no quack) had observed something real; but not, as it would turn out, anything that would break thermodynamics.
The culprit? An absolutely miniscule contamination, so small that it is all but undetectable. When acetaldehyde phenylhydrazone melts, it becomes one of two liquids, based on whether the compound has been exposed to a base or an acid. The former appears at the higher melting point; and the latter at the lower.
The observation of such behavior will be exceedingly rare because it depends on the molecules in the crystal and in the liquid having different geometries, which is unusual. Furthermore, it depends also on the conversion by acid being both possible and rapid.
Part 1
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Dr. Krishna Kumari Challa
The compound is made by dissolving solid acetaldehyde and adding both liquid phenylhydrazine and aqueous ethanol, and chilling until the mixture freezes and forms solid crystals. To then discover the melting point of the newly formed acetaldehyde phenylhydrazone, you have to re-melt it.
This is where the problems emerged. To understand why acetaldehyde phenylhydrazone melts at two distinct temperatures, the researchers first investigated its solid form. But the most cutting edge probes failed to turn up an answer.
All analyses, performed by Threlfall's team and other recent efforts, failed to find a single difference between acetaldehyde phenylhydrazone samples that melted at the lower temperature, and samples that melted at the higher. These techniques included X-ray diffraction, nuclear magnetic resonance, and IR spectroscopy. As far as scientists could tell, the crystals were identical.
The next step was to investigate the liquid the crystals became after melting.
And there, the researchers got a result. There was a subtle, and temporary, but distinct difference. Although the compounds had the same molecular formula, the structure of the initial melt was slightly different, depending on the temperature.
The compound contains a methyl group that is able to have two distinct configurations, known as the Z isomer and the E isomer.
In its solid phase, the material almost exclusively consists of the Z isomer.
The most stable liquid phase is a mix of about one-third Z isomer to two-thirds E isomer. The lower of the two melting points immediately produces the Z and E mix, while the higher melting point is entirely Z, before switching to part E.
Part 2
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A clue was given in a 1905 paper, which pointed out that acetaldehyde phenylhydrazone was extremely sensitive to acid. Threlfall and his team tried exposing their samples to vapors of acid and ammonia. And they found that exposure to just a tiny bit of one or the other could reliably influence the compound's melting point. The acid acts as a catalyst to speed the shift from the Z to E isomer, lowering the melting point in the process.
If an element or compound can exist in two or more distinct crystalline forms, then each form will have different Gibbs energies and melt at its own distinct temperature.
In this case, the molecules of the crystal are in the cis geometry – of groups pointing towards each other – and melt to an identical geometry in the absence of acid at 100 degrees Celsius. However, in the presence of even a trace of acid, the molecules convert on melting to the trans geometry of groups pointing away from each other. This liquid has a smaller Gibbs energy and is more stable, so the melting point becomes 65 degrees Celsius."
It's similar to the effect salt has on water: adding salt to a pot of water raises the freezing and boiling points. Where it takes a lot of salt to invoke a significant change to water's phase transitions, it takes so little acid to alter acetaldehyde phenylhydrazone that it took more than a century – and Threlfall and his colleagues a decade – to figure it out.
This research is a real testament to human curiosity and tenacity. And it gives us hope for the future. How many more mysteries will be solved in the years stretching into a glittering future of discovery?
https://pubs.acs.org/doi/10.1021/acs.cgd.8b01459
Part 3
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yesterday
Dr. Krishna Kumari Challa
Cadavers could be bone-marrow donors
A new technique for collecting bone-marrow stem cells from a cadaver’s spinal column could provide transplants for people with blood cancers. A company called Ossium Health is creating a bank of cryopreserved marrow from organ donors with diverse genetic backgrounds. Unlike solid organ donors, a bone-marrow donor must be a very close genetic match to the recipient. This presents a particular challenge when trying to find donors for people from racial minority groups, who are underrepresented in donor registries. The cadaver bank could widen the potential donor pool, although it is still unclear whether the freezing process could damage the stem cells.
https://www.wired.com/story/stem-cell-donation-deceased-ossium-bone...
yesterday
Dr. Krishna Kumari Challa
Neanderthal adhesive manufacturing site found in Gibraltar cave
Cut into a Gibraltar cliff face overlooking the Alboran Sea, a cave opening leads back in time to one of the earliest manufacturing sites on the planet—a Neanderthal-built tar distillation oven hidden for 65,000 years.
Researchers have discovered a complex Neanderthal hearth structure in Vanguard Cave. Middle Paleolithic stone artifacts and residues suggest Neanderthals produced tar from rockrose plants (Cistaceae) here, showing off their advanced fire management and technological capabilities.
Neanderthals used fire for warmth, light, cooking, landscape clearing, and extracting adhesive tar from specific plants and trees. Evidence of their use of fire in tar extraction is based on the composition of the tar residues left on tools.
Tar was used as an adhesive for hafting stone tools to wooden handles, representing a significant advancement in tool-making, predating current modern human tar adhesive use by more than 100,000 years.
While the techniques Neanderthals used to extract tar have been previously back-engineered to suggest the use of underground fire pits, direct evidence of these pits has been missing from the record.
In the current study, "A Neanderthal's specialized burning structure compatible with tar obtention," published in Quaternary Science Reviews, researchers analyzed a hearth pit structure in Vanguard Cave, employing geochemical, mineralogical, palynological and micromorphological methods.
They identified a central fire pit with two opposite-sided trenches, revealing a crust of altered rocks and sediment due to prolonged fire use. This structure aligns with theoretical models requiring specialized heating installations for tar production under low-oxygen conditions.
Part 1
15 hours ago
Dr. Krishna Kumari Challa
Organic geochemical analysis revealed the presence of levoglucosan and significant amounts of retene in the structure's matrix, compounds associated with the combustion of resinous plant materials. Lipid analysis showed straight-chain n-alkanes of odd carbon numbers and n-alkanols of even carbon numbers, biomarkers indicative of fresh leaf wax from plants like rockrose.
Charcoal analysis uncovered partially vitrified remains of Cistaceae, or rockrose family plants, suggesting incomplete combustion under controlled conditions. Less than 10% of the charcoal was from conifer wood.
Palynological examination indicated the presence of abundant pollen grains within the structure, whereas surrounding sediments were free of pollen. This suggests the deliberate introduction of plant materials into the hearth by Neanderthals.
Micromorphological analysis showed no evidence of clay heating above 500°C, indicating that the structure was used for controlled low-temperature processes compatible with tar production.
Carbonate rocks within the structure appear placed intentionally, likely employed to maintain a seal composed of guano and sand. This seal would create a low-oxygen environment essential for effective tar distillation.
To test their hypothesis, the team conducted experimental archaeology by building a similar structure and using it to heat rockrose leaves under low-oxygen conditions. The experiment successfully produced tar sufficient to haft stone spearheads, using only tools and materials available to Neanderthals in the area.
Findings show Neanderthals organized complex fire-related activities by constructing specialized hearths for tar extraction. This confirms a level of cognitive complexity and cultural development previously expected based on their use of manufactured materials.
Juan Ochando et al, A Neanderthal's specialised burning structure compatible with tar obtention, Quaternary Science Reviews (2024). DOI: 10.1016/j.quascirev.2024.109025
Part 2
15 hours ago
Dr. Krishna Kumari Challa
Study reveals RNA's unknown role in DNA damage repair
A multi-institutional team of researchers has discovered a previously unknown role for RNA.
RNA molecules are best known as protein production messengers. They carry genetic instructions from DNA to ribosomes—the factories inside cells that turn amino acids into the proteins necessary for many cell functions. But this study found that RNA can also help cells repair a severe form of DNA damage called a double-strand break, or DSB.
A DSB means both strands of the DNA helix have been severed. Cells have the tools to make some repairs, but a DSB is significant damage—and if not properly fixed can lead to mutations, cell death, or cancer. (Interestingly, cancer treatments, like chemotherapy and radiation, can also cause DSBs.)
When a DSB happens in DNA, it's like a load-bearing beam in a building breaking. A careful, precise repair is needed to ensure the building's—or the DNA's—stability. The pieces must be rejoined accurately to prevent further damage or mutation. Repairing a damaged building requires having a reliable foreman on the job site. A DSB requires something very similar.
A key mechanism the researchers identified is that RNA can help position and hold the broken DNA ends in place, facilitating the repair process.
Specifically, they found that RNA molecules and the broken section of DNA can match up like puzzle pieces. When RNA has this kind of complementarity with the DNA break site, it acts as a scaffold, or a guide, beyond its traditional coding function, showing the cellular machinery where to make repairs. Over millennia, cells have evolved complex mechanisms to fix DSB, each of them functioning like different tools from the same toolbox.
This research work showed that RNA can influence which tools are used, depending on its complementarity to the broken DNA strands. This means that in addition to being the important protein production messenger, RNA acts as both a foreman and laborer when it comes to DNA repair.
A deeper understanding of RNA's role in DNA repair could lead to new strategies for strengthening repair mechanisms in healthy cells, potentially reducing the harmful effects of treatments like chemotherapy and radiation.
Youngkyu Jeon et al, RNA-mediated double-strand break repair by end-joining mechanisms, Nature Communications (2024). DOI: 10.1038/s41467-024-51457-9
14 hours ago