Furthermore, they found that the high levels of arginine are necessary for tumor development, independently of the amino acid's role in protein synthesis. This then begged the question: How does arginine lead to tumorigenicity?

At high concentrations, arginine binds to a specific factor, which triggers metabolic reprogramming and promotes tumour growth by regulating the expression of metabolic genes. As a consequence, tumour cells revert back to an undifferentiated embryonic cell state, in which they can divide indefinitely. Interestingly, tumour cells also benefit in another way from increasing the uptake of arginine.

Our immune cells depend on arginine to function properly. Therefore, depleting arginine in the tumour environment helps the tumour cells escape the immune system.

What do these findings mean for cancer therapy? The scientists propose to target the specific arginine-binding factor rather than depleting arginine.

Furthermore, metabolic changes such as increased arginine levels may serve as biomarkers for detecting cancer at an early stage, which is crucial for successful cancer treatment and patient survival.

 Arginine reprograms metabolism in liver cancer via RBM39, Cell (2023). DOI: 10.1016/j.cell.2023.09.011. www.cell.com/cell/fulltext/S0092-8674(23)01032-2

Part 2

How male mosquitoes compensate for having only one X chromosome

The research group has discovered the master regulator responsible for balancing the expression of X chromosome genes between males and females in the malaria mosquito.

This discovery helps scientists to better understand the evolution of the epigenetic mechanisms responsible for equalizing gene expression between the sexes. The findings may contribute to the development of new ways to prevent the spread of malaria. 

Just like humans, the sex of a mosquito is determined by the sex chromosomes: females have two X chromosomes (XX), while males have an X and a Y chromosome (XY). This can be problematic, as males have only half the number of X chromosome genes as females, and hence would have only half the amount of proteins from the X chromosome. To compensate for this, there must be a way to increase the expression of X chromosome genes in males.

The researchers discovered that the protein SOA (sex chromosome activation) is the key regulator that balances X chromosome gene expression in male mosquitoes. They found that SOA works by binding to X chromosome genes and increasing their expression, but only in males. Female mosquitoes, on the other hand, only produce a small amount of very short, non-functional SOA.

Balancing gene expression on sex chromosomes is essential for development in some species. However, others do not have such a mechanism at all. It is now discovered that in mosquitoes, balancing X chromosome expression by SOA is not necessary for development, but it does give males a head start.

This is an important clue as to how the mechanisms that balance gene expression on sex chromosomes may have evolved in the first place.

Agata Izabela Kalita et al, The sex-specific factor SOA controls dosage compensation in Anopheles mosquitos, Nature (2023). DOI: 10.1038/s41586-023-06641-0

How do our brains tell us when something goes wrong?

Whether improperly closing a door or shanking a kick in soccer, our brains tell us when we've made a mistake because these sounds differ from what we expect to hear. While it's long been established that our neurons spot these errors, it has been unclear whether there are brain cells that have only one job—to signal when a sound is unexpected or "off."

A team of neuroscientists has now identified a class of neurons—what it calls "prediction-error neurons"—that are not responsive to sounds in general, but only respond when sounds violate expectations, thereby sending a message that a mistake has been made.

Brains are remarkable at detecting what's happening in the world, but they are even better at telling you whether what happened was expected or not. It 's found that there are specific neurons in the brain that don't tell you what happened, but instead tell you what went wrong. Neurons like these might be vital in learning how to speak or how to play a musical instrument. Both of those behaviors involve lots of trial and error, lots of mistakes, and lots of learning from mistakes

Nicholas J. Audette et al, Stimulus-specific prediction error neurons in mouse auditory cortex, The Journal of Neuroscience (2023). DOI: 10.1523/JNEUROSCI.0512-23.2023

Unique voice prints in parrots could help birds be recognized in a flock, no matter what they say

Parrots are exceptional talkers. They can learn new sounds during their entire lives, amassing an almost unlimited vocal repertoire. At the same time, parrots produce calls so they can be individually recognized by members of their flock—raising the question of how their calls can be very variable while also uniquely identifiable.

A study on monk parakeets might have the answer: individuals have a unique tone of voice, known as a voice print, similar to that in humans. This finding in a wild parrot raises the possibility that a voice print might also be present in other vocally flexible species, such as dolphins and bats.

It makes sense for monk parakeets to have an underlying voice print. It's an elegant solution for a bird that dynamically changes its calls but still needs to be known in a very noisy flock.

Humans have complex and flexible vocal repertoires, but we can still recognize each other by voice alone. This is because humans have a voice print: our vocal tract leaves a unique signature in the tone of our voice across everything that we say.

Other social animals also use vocal cues to be recognized. In birds, bats, and dolphins, for example, individuals have a unique "signature call" that makes them identifiable to members of the group. But signature calls encode identity in only one call type. To date, almost no evidence exists for animals having unique signatures that underlie all calls made by an individual. In other words, almost no animals are known to have a voice print.

Like humans, parrots use their tongue and mouth to modulate calls, meaning that their grunts and shrieks sound much more human than a songbird's clean whistle.

Also, like humans, parrots live in large groups with fluid membership. There could be tens of birds vocalizing at the same time. They need a way of keeping track of which individual is making what sound.

Part 1

Armed with shotgun microphones, researchers recorded the calls of hundreds of individuals, collecting over 5000 vocalizations in total, making it the largest study of individually-marked wild parrots to date. Importantly, they re-recorded the same individuals over two years, which revealed how stable the calls were over time.

They then used a set of models to detect how recognizable individuals were within each of the five main call types given by this species. Surprisingly, they found high variability in the so-called "contact call" that birds use to broadcast their identity. This overturned a long-held assumption that contact calls contain a stable individual signal—and suggested that the parakeets are using something else for individual recognition.
To test if voice prints were at play, scientists turned to a machine learning model widely used in human voice recognition, which detects the identity of the speaker using the timber of their voice. They trained the model to recognize calls of individual parrots that were classed as "tonal" in sound.
Once the model was trained on an individual, they then tested to see if the model could detect the same individual from a different set of calls that were classed as "growling" in sound. The model was able to do this three times better than expected by chance, providing evidence that monk parakeets have a voice print, which could allow individuals to recognize each other no matter what they say.

The researchers, however,  caution that the evidence is still preliminary. Before we can speak of a true voice print, we need to confirm that the model can repeat this result when it is trained with more data from more individuals, and that birds can also recognize this timbre in the vocalizations.

Simeon Smeele et al, Evidence for vocal signatures and voice-prints in a wild parrot, Royal Society Open Science (2023). DOI: 10.1098/rsos.230835. royalsocietypublishing.org/doi/10.1098/rsos.230835

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Part 2

Common Plastic Additive Linked to Autism And ADHD

The number of kids being diagnosed with autism spectrum disorder ( ASD) and attention deficit hyperactivity disorder ( ADHD) has risen sharply in recent decades, and a new study points to the common plastic additive bisphenol A (BPA) as a potential reason why. BPA is used in a lot of plastics and plastic production processes, and can also be found inside food and drink cans. However, previous research has also linked it to health issues involving hormone disruption, including breast cancer and infertility.

In this new study, researchers from Rowan University and Rutgers University in the US looked at three groups of children: 66 with autism, 46 with ADHD, and 37 neurotypical kids. In particular, they analyzed the process of glucuronidation, a chemical process the body uses to clear out toxins within the blood through urine.
The research found that kids with ASD and ADHD couldn't clear out BPA and another similar compound called Diethylhexyl Phthalate (DEHP) with as much efficiency as other kids, potentially leading to longer exposure to their toxic effects.

"Detoxification of these two plasticizers is compromised in children with ASD and ADHD," write the researchers in their published paper. "Consequently, their tissues are more exposed to these two plasticizers."

It was only in the case of BPA that the difference was statistically significant though: the efficiency was reduced by about 11 percent for kids with ASD and 17 percent for kids with ADHD, compared with the control group of children.
Part 1

The researchers think that gene mutations in certain individuals means that BPA can't be cleared as well as it needs to be, which means the substance sticks around in the body. That potentially could cause damage in terms of neuron development and operation.

Conditions like ASD and ADHD are thought to be brought on by a combination of genetic and environmental influences, and this new study brings together both of them. However, it's only part of the story – not every child with a neurodevelopmental disorder had problems flushing out BPA, so there are other factors at play, too.

Work is continuing to identify how exactly ASD and ADHD take hold in the body – whether it's in utero before birth for example, or later on in life – as the data isn't enough to show whether BPA exposure causes either disorder.

"There is an extensive body of epidemiological evidence for a relationship between neurodevelopmental disorders and environmental pollutants such as plasticizers," write the researchers.

"How important plasticizer originated neurodevelopmental disorder is in the overall occurrence of these disorders is not known, but it must account for a significant proportion or would not have been so easy to detect in a metabolic study of moderate size such as this study."

https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0...

Part 2

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Digital watermark protections can be easily bypassed

Perhaps the most chilling aspect of AI is its capacity to generate deepfake images.

But recent developments portend a more unsettling trend as digital fakery turns malicious. Not only celebrities and politicians, ordinary citizens are targeted, too. People's faces are appearing in images on social media without their consent. 

Major digital media companies—OpenAI, Alphabet, Amazon, DeepMind—have promised to develop tools to combat disinformation. One key approach is the use of watermarking on AI-generated content.

A paper published Sept. 29 on the preprint server arXiv raises troubling news about the ability to curb such digital abuse.

Researchers ran tests demonstrating easy run-arounds of protective watermarks.

We don't have any reliable watermarking at this point because the researchers broke them all!

The team used a process called diffusion purification, which applies Gaussian noise to a watermark and then removes it. It leaves a distorted watermark that can bypass detection algorithms. The rest of the image is only minimally altered.

They further successfully demonstrated that bad actors with access to black-box watermarking algorithms could foist fake photos with markings that trick detectors into believing they are legitimate.

Better algorithms will certainly come along. As has been the case with viral attacks, the bad guys will always be working to break whatever defenses the good guys come up with, and the cat-and-mouse game will continue.

Mehrdad Saberi et al, Robustness of AI-Image Detectors: Fundamental Limits and Practical Attacks, arXiv (2023). DOI: 10.48550/arxiv.2310.00076

How synthesized plankton molecules inhibit cancer proteins

Researchers have discovered how to harness the toxic power of plankton to manufacture anti-cancer molecules.

In a paper, "Synthesis of portimines reveals the basis of their anti-cancer activity," published in Nature, the team details the steps taken in synthesizing marine toxins, portimine A and portimine B, enabling in-depth investigations into their properties

Dinoflagellate-derived cyclic imine toxins, specifically portimine A and portimine B, are of interest due to their potential anti-cancer therapeutic properties. Previous research has shown the effects of cyclic imine toxins on cancer cells, but the molecular mechanisms underlying the cause of the anti-cancer activity were unknown. Access to these toxins in large quantities is currently hard to come by as the only known producer is a type of tiny marine plankton, Vulcanodinium rugosum. To test the toxin's activity, the researchers first needed to innovate a way to synthesize large enough quantities to work with.

The synthesis began with constructing a minimally-decorated carbon skeleton devoid of most oxygen atoms. The idea was to leverage a macrocycle's innate reactivity to install the correct oxygenation pattern and stereochemistry.

Strategic ring-chain tautomerization events were employed to facilitate the synthesis using ring-closing alkyne metathesis to construct the 14-membered macrocycle in the portimines' skeleton. The innovation represents a scalable and concise synthesis of portimines. With the desired molecules created, the next step was to see how they interacted with cancer cells.

Part 1

The team tested interactions across a broad panel of 20 human and mouse cancer cell lines, ranging from Jurkat leukemia to metastatic human fibrosarcoma cells, triple-negative breast cancer and glioblastoma brain-tumor-initiating cell lines. Consistent potent cytotoxic activity was observed across the entire panel of cancer cell lines that were evaluated with portimine A. The fully synthetic portimine B was found to be substantially less effective.

Portimine A was identified as a potent inducer of apoptosis in various cancer cell lines, including MC38 cells, a colorectal carcinoma testing model. The apoptosis caused by portimine A had minimal effects on non-cancerous cells and low toxicity in mice.
Specifically, portimine A was found to target the 60S ribosomal export protein NMD3, blocking polysome formation and inhibiting protein translation and was observed to be an effective agent for suppressing tumor growth in vivo.

The exposure time to portimine A was limited by its half-life of around 30 minutes. The short duration still resulted in a significant reduction in tumor growth, indicating a very potent activity and potential therapeutic uses in the future.

Junchen Tang et al, Synthesis of portimines reveals the basis of their anti-cancer activity, Nature (2023). DOI: 10.1038/s41586-023-06535-1

The chemical synthesis and anti-cancer properties of portimines, Nature (2023). DOI: 10.1038/d41586-023-02788-y

Part 2

Study challenges the rules of evolutionary biology

Charles Darwin said that evolution was constantly happening, causing animals to adapt for survival. But many of his contemporaries disagreed. If evolution is always causing things to change, they asked, then how is it that two fossils from the same species, found in the same location, can look identical despite being 50 million years apart in age?

Everything changed in the past 40 years, when an explosion of evolutionary studies proved that evolution can and does occur rapidly—even from one generation to the next. Evolutionary biologists were thrilled, but the findings reinforced the same paradox: If evolution can happen so fast, then why do most species on Earth continue to appear the same for many millions of years?

This is known as the paradox of stasis and researchers set out to investigate it. 

  They conducted a long-term study in a community of lizards, measuring how evolution unfolds in the wild across multiple species. In doing so, he may have found the answer to one of evolution's greatest challenges.

The research was published as the cover story in the Proceedings of the National Academy of Sciences.

Scientists call this a paradox because it doesn't seem to make any sense. The most common explanation is that natural selection  is working to stabilize a species' appearance, with the assumption that an average form will help them survive the best. The problem is, when people do field studies, they almost never find that this kind of 'stabilizing' selection actually exists

Part 1

Scientists set up a field study with four different species of Anolis lizards (anoles) on a small island at the Fairchild Tropical Botanic Gardens in Coral Gables, Florida. They measured natural selection in all four lizard species over five consecutive time periods by catching and monitoring the survival of every lizard on the island.

The researchers searched day and night for lizards. Using long fishing poles with tiny lassos at their tips, they gently captured them by their strong necks, placed them in coolers, and documented the exact branch or stump where they found each lizard.

Back in the lab, they measured the lizards' heads, legs, feet, weight, and even the stickiness of their toes. After assigning an identifying number to each lizard and marking them with a tiny tag under the skin, the team released the lizards to the same branches where they'd found them. They went out in the following days and weeks to catch the rest of them.

Every six months for three years, the researchers started the process over again. Catching the same lizards, taking measurements, releasing them, and making notes of which lizards survived and which didn't.

For a very long time, evolutionary biologists have tried to figure out what was behind this paradox of stasis idea," the scientists said. "What this study shows is that the answer may not be particularly complicated—we just had to conduct a study in the wild for a long enough time to figure it out."

Stroud, James T. et al, Fluctuating selection maintains distinct species phenotypes in an ecological community in the wild, Proceedings of the National Academy of Sciences (2023). DOI: 10.1073/pnas.2222071120. doi.org/10.1073/pnas.2222071120

Part 3

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Firefighting Fungi
Underneath every mushroom is a sprawling, branching network of rootlike structures called a mycelium. Now researchers have successfully grown these networks into Pop Tart–size sheets that could act as a fire retardant in building materials. Mycelium contains a lot of carbon. When exposed to fire, the sheet briefly burns, releasing water and carbon dioxide into the air, before petering out and leaving behind a black layer of carbon.

Why this is so cool: Unlike asbestos, which is still sometimes added to building materials as a fire retardant, mycelium does not shed noxious compounds when exposed to fire. Mycelium could replace the fire-retardant foam that insulates many commercial buildings, which can produce carbon monoxide and other toxic products when it combusts. Mycelium is also a biological material, and any waste it leaves behind is compostable.

What the experts say: “If the product reaches the end of its life, you can just chuck that mycelium in your garden,” says Everson Kandare an engineer at RMIT University in Melbourne, Australia. “Just toss it in the green beans.”

Remnant of cell division could be responsible for spreading cancer

Once thought to be the trash can of the cell, a little bubble of cellular stuff called the midbody remnant is actually packing working genetic material with the power to change the fate of other cells—including turning them into cancer.

When one cell divides into two, a process called mitosis, the result is not just the two daughter cells.

One cell divides into three things: two cells and one midbody remnant, a new signaling organelle. The midbody is full of genetic information, RNA, that doesn't have much to do with cell division at all, but likely functions in cell communication.

Researchers  analyzed the contents of midbodies—which form between the daughter cells during division—and tracked the interactions of the midbody remnants set free after cell division. Their results point to the midbody as a vehicle for the spread of cancer throughout the body.

What the researchers found inside midbodies was RNA—which is a kind of working copy of DNA used to produce the proteins that make things happen in cells—and the cellular machinery necessary to turn that RNA into proteins. The RNA in midbodies tends to be blueprints not for the cell division process but for proteins involved in activities that steer a cell's purpose, including pluripotency (the ability to develop into any of the body's many different types of cells) and oncogenesis (the formation of cancerous tumours).

A midbody remnant is very small. It's a micron in size, a millionth of a meter. But it's got everything it needs to sustain that working information from the dividing cell. And it can drift away from the site of mitosis, get into your bloodstream and land on another cell far away.

Part 1

Many midbody remnants are reabsorbed by one of the daughter cells that shed them, but those that touch down on a distant surface, like a lunar lander, may instead be absorbed by a third cell. If that cell swallows the midbody, it may mistakenly begin using the enclosed RNA as if it were its own blueprints.

Previous research showed that cancer cells are more likely than stem cells to have ingested a midbody and its potentially fate-altering cargo. Stem cells, which give rise to new cells and are valuable for their pluripotency, spit a lot of midbodies back out, perhaps to maintain their pluripotency.

Future research may be able to harness the power of midbody RNA to deliver drugs to cancer cells or to keep them from dividing.

The researchers identified a gene, called Arc, that is key to loading the midbody and midbody remnant with RNA. Taken up long ago from an ancient virus, Arc also plays a role in the way brain cells make memories.

Sungjin Park et al, The mammalian midbody and midbody remnant are assembly sites for RNA and localized translation, Developmental Cell (2023). DOI: 10.1016/j.devcel.2023.07.009

Part 2

Vacuum cleaner-effect in fungi can hold nanoplastics at bay

Researchers have investigated the effect of tiny polystyrene particles on bacteria and fungi. While these nanoplastics reduced both bacterial and fungal growth, the fungus actually managed to "clean up" their surroundings, thereby easing the effect of the plastics. 

Nanoplastics have been proven to induce toxicity in diverse organisms, yet very little is known how this new pollutant is affecting the soil ecosystem. To study these nanoparticles of polystyrene, the researchers used microfluidic chips, a growth system that allowed them to observe interactions of single cells with the plastics under the microscope.

At the highest nanoplastics concentration, the fungi caught most of the tiny plastics present in their vicinity, in a process that  the researchers labeled the 'vacuum cleaner effect.' Overall, they found that nanoplastics can cause a direct negative effect on the soil microbes. This highlights the need for further studies that can explain how the microbial stress response might affect soil functions.

The nanoplastic particles clung to the surface of the fungal branches in such a way that the surroundings were almost nanoplastic-free. The fungus cleaned up its surroundings under high concentrations, and could then grow better again. Although the results of the study were confirmed for many conditions, the researchers point out that it might be species dependent.

This serves as a reminder to reduce our plastic waste and the pollution of soils. Finding fungi that can specifically collect nanoplastics from the soil solution may help other organisms to sustain the pollution better, and perhaps attract bacteria that can break down plastics. The fungal 'vacuum cleaner' is not an easy fix for the problem, but can give a little hope for the future.

Paola M. Mafla-Endara et al, Exposure to polystyrene nanoplastics reduces bacterial and fungal biomass in microfabricated soil models, Science of The Total Environment (2023). DOI: 10.1016/j.scitotenv.2023.166503

Models suggest interlinking rivers in India to meet water demand may adversely impact monsoon rainfall amounts

A team of civil engineers and meteorologists at the Indian Institute of Technology, working with colleagues from the Indian Institute of Tropical Meteorology and the University of Hyderabad, has found, via modeling, that a plan to interlink rivers in India to capture rain runoff could inadvertently have a negative impact on the amount and location of monsoon rainfall.

In their study, published in the journal Nature Communications, the group used a variety of modeling techniques to test the possibility of unintended changes to weather patterns in India as interlinking projects are undertaken.

Officials in India have a clear problem on their hands—their country has a population of 1.4 billion people, the highest of any country in the world. And it is still growing. Such growth is presenting a host of problems, including how to feed so many people, sustain economic growth and manage water. This last problem has become dire—for India to feed its people, it must grow more food and that will require more water. But water availability is decreasing. To meet the demand, scientists and government officials have proposed and instigated a plan that entails digging canals between rivers to interlink them, with the idea of capturing more rainfall. Instead of allowing most of its rainfall to run off into rivers and then to the sea, the country plans to divert some of that water into other rivers that can be shunted into drier areas, where it can be used for irrigation. But doing so, the researchers on this new effort insist, could have unintended and perhaps disastrous side effects.

Part 1

Prior research has shown that exchange of material such as aerosols into the atmosphere can lead to a land-atmospheric feedback system, resulting in cooling of temperatures in a region, and subsequent changes in rainfall amounts. Likewise, irrigation efforts have been found to instigate land-atmosphere feedback as water from such systems evaporates into the atmosphere. Such systems have been found to have an impact on local hydrological cycles, and in some cases, can impact monsoon rains. These findings convinced the team on this new effort to take a closer look at the possible impact of interlinking rivers.

To estimate possible impacts, the team used causal delineation techniques along with general climate models that have been modified to focus specifically on India and its weather, and also a reanalysis of datasets built from land-atmosphere feedback systems that already exist in India.

The researchers found that land-atmosphere feedbacks from interlinked rivers could generate causal pathways between river basins in India—as one example, they found incidences of decreased rainfall in September (during monsoon season) by up to 12% in parts of the country that are already experiencing water shortages. They also found evidence of some areas experiencing more dryness during El Niño years. They conclude that more study is required before approving new river linking efforts.

Tejasvi Chauhan et al, River interlinking alters land-atmosphere feedback and changes the Indian summer monsoon, Nature Communications (2023). DOI: 10.1038/s41467-023-41668-x

Part 2

Why eyeballing four is easy but five is hard

Our brains use one mechanism to size up four or fewer items, and a different one f... — which is why doing the latter is so much harder. The brain contains specialized neurons that fire when we see a specific number of objects: some fire primarily when presented with one dot on a screen, for example. Brain scans of 17 people revealed that the neurons specializing in numbers of four or less responded very specifically and selectively to their preferred number. Neurons that specialize in five through nine responded strongly not only to their preferred number, but also to numbers immediately adjacent to it.

https://www.nature.com/articles/s41562-023-01709-3.epdf?sharing_tok...

Copycat nutrient leaves pancreatic tumors starving

A study by scientists suggests an entirely new approach to treat pancreatic cancer. The research shows that feeding tumors a copycat of an important nutrient starves them of the fuel they need to survive and grow. The method, described in the journal Nature Cancer, has been used in early clinical trials for lung cancer. However, the unique properties of pancreatic cancer may make the strategy an even stronger candidate in the pancreas.

Pancreatic cancer relies on the nutrient glutamine much more than other cancers, so therapies that can interfere with tumors' ability to access glutamine could be highly effective.

Pancreatic cancer is relatively rare, accounting for only 3% of all cancers. However, it has one of the lowest survival rates among cancers: most people only live three to six months after being diagnosed with this disease.

One of the challenges of treating pancreatic cancer has to do with the physical properties of the tumors themselves.

Pancreatic tumors tend to be packed in dense connective tissue that keeps them encapsulated from the rest of the body and cuts off their supply of oxygen. As a consequence, these cancers develop unique metabolic properties compared to other tumors, and this is something we may be able to exploit with new treatments.

Part 1

One of the metabolic quirks of pancreatic cancer is that it relies heavily on glutamine to produce energy for growth and survival. In the past, scientists have tried to block access to glutamine to slow the growth of pancreatic tumors, but this is easier said than done.

The new method relies on a molecule called DON that has structural similarities to glutamine but can't actually be used as a nutrient source. By studying mice, the research team found that DON significantly slowed pancreatic tumour growth and stopped the tumors from spreading.

Although DON was able to stop pancreatic tumors from using glutamine, pancreatic cancer cells can use other nutrients to grow in glutamine's absence. To combat this effect, the researchers combined DON with an existing cancer treatment that blocks the metabolism of asparagine, another important nutrient. The combined treatment had a synergistic effect, helping prevent the spread of pancreatic tumors to other distant organs, such as the liver and lungs.

This could be a game changer for pancreatic cancer, and a lot of the preclinical work needed to rationalize it and is already happening.

Maria Victoria Recouvreux et al, Glutamine mimicry suppresses tumor progression through asparagine metabolism in pancreatic ductal adenocarcinoma, Nature Cancer (2023). DOI: 10.1038/s43018-023-00649-1

Part 2

Evidence that albatrosses use infrasound to navigate long journeys

A new study  provides the first evidence that wandering albatrosses, one of the widest-ranging seabirds, may use infrasound to help them navigate long and featureless foraging trips covering thousands of miles.

Researchers show that albatrosses  orientate towards areas of "loud" microbarom infrasound when flying on long distance foraging trips. The paper published on this work is titled "Albatross movement suggests sensitivity to infrasound cues at sea."

Infrasound is a form of low-frequency sound that is inaudible to humans but is ubiquitous in the marine environment. Microbaroms are a type of infrasound associated with colliding ocean waves. Such wavy areas are also associated with strong winds, which albatrosses depend on to help them fly efficiently. The researchers used GPS trackers to determine the flight paths of 89 wandering albatrosses breeding in the Crozet Islands archipelago, Southern Ocean, over the course of their foraging trips to sea, which can last up to a month. They then compared these flight paths to modeled acoustic maps that the team had developed to represent the distribution of microbarom infrasound.

This revealed that wandering albatrosses orientate towards areas of "loud" microbarom infrasound when departing on bouts of directed flight, suggesting that they may perceive and respond to microbarom infrasound propagated over long distances.

 Natasha Gillies et al, Albatross movement suggests sensitivity to infrasound cues at sea, Proceedings of the National Academy of Sciences (2023). DOI: 10.1073/pnas.2218679120

How plant-derived nutrients can affect the gut and brain

Can plant-derived nutrients alter gut bacteria to affect brain function? Scientists investigated this question in a study of overweight adults.

Their findings, published in the journal Gut, suggest that dietary fiber can exert influence on both the composition of gut bacteria and the reward signals in the brain and associated food decision-making. Prebiotics are used to foster the colonization of beneficial bacteria in the gut. These indigestible dietary fibers are found in plant-derived foods such as onions, leeks, artichokes, wheat, bananas, and in high concentrations in chicory root. They support gut health by promoting the growth and activity of beneficial gut bacteria. Researchers have now investigated whether certain prebiotics can also influence brain function by improving communication between the gut microbiome and the brain.

The study shows consumption of high-dose dietary prebiotics leads to a reduction in reward-related brain activation in response to high-calorie food stimuli. The results suggest a potential link between gut health and brain function, in this case food decision-making.

The findings, derived from advanced neuroimaging, next-generation sequencing of gut bacteria, and combined analyses of potential metabolic pathways, suggest that functional microbial changes may underlie the altered brain response towards high-caloric food cues. 

A better understanding of the underlying mechanisms between the microbiome, gut, and brain could help to develop new strategies that promote healthier eating habits in people at risk.

Evelyn Medawar et al, Prebiotic diet changes neural correlates of food decision-making in overweight adults: a randomised controlled within-subject cross-over trial, Gut (2023). DOI: 10.1136/gutjnl-2023-330365

Study shows live plant pathogens can travel on dust across oceans

Plant pathogens can hitch rides on dust and remain viable, with the potential for traveling across the planet to infect areas far afield, a finding with important implications for global food security and for predicting future outbreaks.

A study, "Assessing Long-distance Atmospheric Transport of Soilborne Plant Pathogens," published in the journal Environmental Research Letters, is the first to provide computer modeling evidence to support the idea that massive dust storms can transport viable pathogenic spores across continents and oceans.

The researchers found that viable spores of the deadly fungal plant pathogen Fusarium oxysporum (F. oxy) could be transported across the ocean and were likely deposited across a range of regions that include agricultural production zones.

The researchers found that this Godzilla ( a major dust storm) dust event could have potentially brought over 13,000 viable live spores, which is not a lot, but it's never been shown before, by any means, that viable soilborne pathogens could be transported trans-oceanically with dust.

Hannah Brodsky et al, Assessing long-distance atmospheric transport of soilborne plant pathogens, Environmental Research Letters (2023). DOI: 10.1088/1748-9326/acf50c

Сoconut shells can make concrete more durable

Scientists have found that concrete's compressive strength can be increased by 4.1% and its flexural strength by 3.4% by adding a small amount of coconut shell (only 5%). The material's performance increased by 6.1% compared to clear concrete. This effect is due to the fact that the cement paste—the bridge between all solid concrete particles—penetrates into the pores of the shell, firmly binding it with other components.

These results show that large amounts of coconut shell can be recycled without harm to the environment while improving the quality of building materials.

Sergey A. Stel'makh et al, Alteration of Structure and Characteristics of Concrete with Coconut Shell as a Substitution of a Part of Coarse Aggregate, Materials (2023). DOI: 10.3390/ma16124422

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Animals find humans scarier than lions

Human voices evoke more fear among animals living in the South African savanna than do snarls from lions. Researchers set up speakers near 21 water holes, which played one of several sounds when triggered by animal movement. When they heard humans, giraffes, leopards, elephants and 16 other species were twice as li... as when they heard growling lions, barking dogs or guns. The researchers suggest that recordings of human voices could be used to keep animals away from areas where a lot of poaching happens.

https://www.cell.com/current-biology/fulltext/S0960-9822(23)01169-7?utm_source=Nature+Briefing&utm_campaign=00a3d0b50b-briefing-dy-20231010&utm_medium=email&utm_term=0_c9dfd39373-00a3d0b50b-44672165

Bionic hand merges with user's nervous and skeletal systems, remaining functional after years of daily use

A woman's life took a dramatic turn when a farming accident claimed her right arm more than 20 years ago. Since then, she has endured excruciating phantom limb pain.

In addition to her intractable pain, she found that conventional prostheses were uncomfortable and unreliable, and thus of little help in daily life. All this changed when she received groundbreaking bionic technology that allowed her to wear a much more functional prosthesis comfortably all day. The higher integration between the bionics and her residual limb also relieved her pain. 

Mechanical attachment and reliable control are two of the biggest challenges in artificial limb replacement. People with limb loss often reject even the sophisticated prostheses commercially available due to these reasons, after experiencing painful and uncomfortable attachment with limited and unreliable controllability. A multidisciplinary group of engineers and surgeons solved these problems by developing a human–machine interface that allows the prosthesis to be comfortably attached to the user's skeleton via osseointegration, while also enabling electrical connection with the nervous system via electrodes implanted in nerves and muscles. This research is now published in the journal Science Robotics.

 Max Ortiz-Catalan et al, A highly integrated bionic hand with neural control and feedback for use in daily life, Science Robotics (2023). DOI: 10.1126/scirobotics.adf7360. www.science.org/doi/10.1126/scirobotics.adf7360

NASA asteroid sample contains life-critical water and carbon

A sample collected from the 4.5-billion-year-old asteroid Bennu contains abundant water and carbon, NASA revealed on Wednesday, offering more evidence for the theory that life on Earth was seeded from outer space

The discovery follows a seven-year-round-trip to the distant rock as part of the OSIRIS-REx mission, which dropped off its precious payload in the Utah desert last month for painstaking scientific analysis.

"This is the biggest carbon-rich asteroid sample ever returned to Earth," NASA administrator Bill Nelson said at a press event at the Johnson Space Center in Houston, where the first images of black dust and pebbles were revealed.

Carbon accounted for almost five percent of the sample's total weight, and was present in both organic and mineral form, while the water was locked inside the crystal structure of clay minerals, he said.

Scientists think the reason Earth has oceans, lakes and rivers is because it was hit with water-carrying asteroids 4 to 4.5 billion years ago, making it a habitable planet.

All life on Earth meanwhile is based on carbon, which forms bonds with other elements to produce proteins and enzymes as well as the building blocks of genetic code, DNA and RNA.

The findings were made through a preliminary analysis involving scanning electron microscopy, X-ray computed tomography and more.

Research finds commonly-used herbicide is harmful to adolescent brain function

Herbicides are the most used class of pesticides worldwide, with uses in agriculture, homes and industry. Exposures to two of the most popular herbicides were associated with worse brain function among adolescents, according to a study  by researchers.

 Researchers reported measuring metabolite concentrations of two commonly used herbicides—glyphosate and 2,4-dichlorophenoxyacetic acid (2,4D)—and the insect repellent DEET in urine samples collected in 2016 from 519 adolescents, aged 11 to 17, living in the agricultural county of Pedro Moncayo, Ecuador. Researchers also assessed neurobehavioral performance in five areas: attention and inhibitory control, memory and learning, language, visuospatial processing, and social perception.

Many chronic diseases and mental health disorders in adolescents and young adults have increased over the last two decades worldwide, and exposure to neurotoxic contaminants in the environment could explain a part of this increase, according to the researchers. 

Part 1

Among the findings:

• Glyphosate, a nonselective herbicide used in many crops, including corn and soy, and for vegetation control in residential settings, was detected in 98% of participants.
• 2,4D, a broadleaf herbicide used on lawns, aquatic sites, and agricultural crops, was detected in 66% of participants.
• Higher amounts of 2,4D in urine were associated with lower neurobehavioral performance in the domains of attention and inhibitory control, memory and learning, and language.
• Glyphosate concentration in urine was associated with lower scores in social perception only, while DEET metabolites were not associated with neurobehavioral performance.

Following the introduction of genetically modified, glyphosate-resistant "Roundup-ready" crops in 1996 and 2,4D resistant crops in 2014, there have been substantial increases in glyphosate and 2,4D use, making them the most widely used herbicides in the world, they wrote in a published paper.

Briana Chronister et al, Urinary glyphosate, 2,4-D and DEET biomarkers in relation to neurobehavioral performance in Ecuadorian adolescents in the ESPINA cohort, Environmental Health Perspectives (2023). DOI: 10.1289/EHP11383

Part 2

Birds disperse eaten insects' eggs

Relationship patterns among flightless stick insects suggest that birds disperse the eggs after eating gravid females. Now this is shown to be true in a new study.

 Most species of stick insects are flightless, yet they are distributed over wide distances and across geographical features that would impede the expansion of flightless animals. This has caused researchers to think that their eggs might be dispersed by birds feeding on gravid females, much in the same way as many plant species rely on birds eating their seeds together with fruits and dispersing them while the seeds pass through the digestive tracts of the birds unharmed.

Experimental studies with Ramulus mikado, a common stick insect in Japan, had suggested that this is possible, but since direct observation of such an event in nature is highly unlikely, it has been unclear whether this mechanism actually contributes to the distribution of the insect.

So researchers turned to the analysis of the relationship patterns of Ramulus mikado populations. They made use of the idea of genetic isolation by geographic distance. 

According to this idea, when individual dispersal distances are smaller, such as in flightless insects, the accumulation of genetic mutations eventually leads to a positive correlation between genetic differentiation among locations and the geographic distance that separates them. Thus, the genetic variation between different populations can be a proxy for the species' rate of dispersal.

The results, published in the journal Proceedings of the Royal Society B, paint a vivid picture. Among many genes where the differences correlated with the geographic distance, the team found a few examples of genes that were clearly closely related even though they were geographically separated by up to hundreds of kilometers and across geographic features that these animals usually cannot overcome.

Astonishingly, amidst a sea of limited active dispersal, they discovered identical genotypes jumping across vast distances, strongly indicating the past occurrence of passive long distance genetic dispersal.

In other words, a few of the flightless insects must have flown from place to place, and the only plausible way in which this could happen is that the eggs of the insects survive the passage through the digestive tract of birds that eat them.

And the insect eggs were seen in bird faeces. 

Part 1

Why this type of dispersal not seen among other insects? 

The eggs of most insect species are typically fertilized just before being laid, relying on sperm stored within the female insects after copulation. However, in some stick insect species, females are parthenogenic, that is, they can produce viable eggs without fertilization. It is only because of this quirk in their nature that viable stick insect babies can hatch from the eggs.

Suetsugu Kenji et al, Phylogeographical evidence for historical long-distance dispersal in the flightless stick insect Ramulus mikado, Proceedings of the Royal Society B: Biological Sciences (2023). DOI: 10.1098/rspb.2023.1708. royalsocietypublishing.org/doi … .1098/rspb.2023.1708

Part 2

Gene editing makes chickens flu-resistant

Bird-flu-resistant chickens have been created using CRISPR gene editing. When exposed to the flu virus, nine out of ten of the animals remained uninfected and didn’t pass the virus to other birds. Researchers modified a gene encoding a chicken protein that the virus needs to replicate. But this prompted the virus to start replicating using other proteins in the same family, which the researchers think could be addressed with more edits. “We must be careful not to facilitate adaptations of the virus that make it more dangerous than it [already] is,” says virologist and study co-author Wendy Barclay.

https://english.elpais.com/science-tech/2023-10-10/the-same-lab-tha...

https://www.nature.com/articles/s41467-023-41476-3.epdf?sharing_tok...

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Simulations of 'backwards time travel' can improve scientific experiments

Physicists have shown that simulating models of hypothetical time travel can solve experimental problems that appear impossible to solve using standard physics.

If gamblers, investors and quantum experimentalists could bend the arrow of time, their advantage would be significantly higher, leading to significantly better outcomes. Researchers at the University of Cambridge have shown that by manipulating entanglement—a feature of quantum theory that causes particles to be intrinsically linked—they can simulate what could happen if one could travel backwards in time. So that gamblers, investors and quantum experimentalists could, in some cases, retroactively change their past actions and improve their outcomes in the present. Whether particles can travel backwards in time is a controversial topic among physicists, even though scientists have previously simulated models of how such spacetime loops could behave if they did exist. By connecting their new theory to quantum metrology, which uses quantum theory to make highly sensitive measurements, the Cambridge team has shown that entanglement can solve problems that otherwise seem impossible.

 David R. M. Arvidsson-Shukur et al, Nonclassical Advantage in Metrology Established via Quantum Simulations of Hypothetical Closed Timelike Curves, Physical Review Letters (2023). DOI: 10.1103/PhysRevLett.131.150202

Study finds we can respond to verbal stimuli while sleeping

Sleep is not a state in which we are completely isolated from our environment: while we sleep, we are capable of hearing and understanding words. These observations, the result of close collaboration between various research teams call into question the very definition of sleep and the clinical criteria that make it possible to distinguish between its different stages.

Sleep is generally defined as a period during which the body and mind are at rest—as if disconnected from the world. However, a new study shows that the frontier between wakefulness and sleep  is much more porous than it seems.

The researchers have shown that ordinary sleepers can pick up verbal information transmitted by a human voice and respond to it by contracting their facial muscles. This astonishing ability occurs intermittently during almost all stages of sleep—like windows of connection with the outside world were temporarily opened on this occasion. These new findings suggest that it may be possible to develop standardized communication protocols with sleeping individuals to understand better how mental activity changes during sleep. On the horizon: a new tool to access the cognitive processes that underlie both normal and pathological sleep.

Part 1

Even if it seems familiar because we indulge in it every night, sleep is a highly complex phenomenon. Our research has taught us that wakefulness and sleep are not stable states: on the contrary, we can describe them as a mosaic of conscious and seemingly unconscious moments. It is essential to decipher the brain mechanisms underlying these intermediate states between wakefulness and sleep. "When they are dysregulated, they can be associated with disorders such as sleepwalking, sleep paralysis, hallucinations, the feeling of not sleeping all night, or on the contrary of being asleep with your eyes open.

To distinguish between wakefulness and the different stages of sleep, researchers usually use physiological indicators such as specific brain waves made visible through electroencephalography. Unfortunately, these indicators do not provide a detailed picture of what is happening in the minds of sleepers; sometimes, they even contradict their testimonies.

Part 2

To explore this avenue, the researchers recruited 22 people without sleep disorders and 27 patients with narcolepsy—that is, people who experience uncontrollable episodes of daytime sleepiness. People with narcolepsy have the particularity of having many lucid dreams,  in which they are aware of being asleep; some can sometimes even shape their dream scenario as they wish.

In addition, they easily and quickly enter REM sleep (the stage where lucid dreaming occurs) during the day, making them good candidates for studying consciousness during sleep under experimental conditions.

Participants in the study were asked to take a nap. The researchers gave them a "lexical decision" test, in which a human voice pronounced a series of real and made-up words. Participants had to react by smiling or frowning to categorize them into one or the other of these categories. Throughout the experiment, they were monitored by polysomnography—a comprehensive recording of their brain and heart activity, eye movements, and muscle tone.

Upon waking up, participants had to report whether they had or had not had a lucid dream during their nap and whether they remembered interacting with someone.

Most of the participants, whether narcoleptic or not, responded correctly to verbal stimuli while remaining asleep. These events were certainly more frequent during lucid dreaming episodes, characterized by a high level of awareness. 

By cross-referencing these physiological and behavioral data and the participants' subjective reports, the researchers also showed that it is possible to predict the opening of these windows of connection with the environment, i.e., the moments when sleepers were able to respond to stimuli. They were announced by an acceleration in brain activity and by physiological indicators usually associated with rich cognitive activity.

Türker B. et al. Behavioral and brain responses to verbal stimuli reveal transient periods of cognitive integration of the external world during sleep. Nature Neuroscience (2023). DOI: 10.1038/s41593-023-01449-7. www.nature.com/articles/s41593-023-01449-7

Part 3

Restoring nerve-muscle connections boosts strength of aging mice, study finds

A small molecule previously shown to enhance strength in injured or old laboratory mice does so by restoring lost connections between nerves and muscle fibers,  researchers have found.

The molecule, called PGE2, blocks the activity of an aging-associated enzyme, or gerozyme, called 15-PGDH that naturally increases in muscles as they age. The study showed that levels of the gerozyme increase in muscles after nerve damage and that it is prevalent in muscle fibers of people with neuromuscular diseases. The research is the first to show that damaged motor neurons—nerves connecting the spinal cord to muscles—can be induced to regenerate in response to a drug treatment and that lost strength and muscle mass can be at least partially regained. It suggests that, if similar results are seen in humans, the drug may one day be used to prevent muscle loss of muscle strength due to aging or disease or to hasten recovery from injury.

 Mohsen A. Bakooshli et al, Regeneration of neuromuscular synapses after acute and chronic denervation by inhibiting the gerozyme 15-prostaglandin dehydrogenase, Science Translational Medicine (2023). DOI: 10.1126/scitranslmed.adg1485

Large trial shows taking less blood for lab testing reduces transfusions in intensive care

A world-first clinical trial published in JAMA could provide an easy way to save tens of thousands of units of blood every year worldwide.

The trial, which involved more than 27,000 patients in 25 adult intensive care units (ICUs) across Canada, showed that taking less blood for lab tests using "small-volume" tubes reduced the need for almost one blood transfusion for every 10 patients. Most hospitals use standard tubes that automatically draw four to six milliliters (ml) of blood, but a typical laboratory test requires less than 0.5 ml of blood, meaning the rest (more than 90%) is wasted. Commercially available small-volume tubes have a weaker vacuum inside that automatically draws up to half as much blood. "While the amount of blood drawn per tube is relatively small, ICU patients typically require multiple blood samples taken multiple times every day. This can add up to significant blood loss that contributes to anemia, or low red blood cells. ICU patients are unable to produce more red blood cells to correct for this blood loss and often require treatment with a blood transfusion.

This trial showed that we can save one blood transfusion for every 10 ICU patients by simply switching to small-volume tubes for blood collection.

At a time when everyone is trying to find ways to make health care more sustainable, and preserve our supply of blood products, this study provides a simple solution that can be implemented without additional cost or negative effects. The study also has important implications for patients, as low red blood cells (anemia) can leave patients feeling tired and weak and is associated with can lead to other complications and longer hospital stays. While blood transfusions can usually correct anemia, there can be rare side effects, such as difficulty breathing, allergic reactions and infections.
Part 1

By the numbers

• 97: Percentage of patients who develop anemia after eight days in the ICU
• 50: Percentage of transfusions given in the ICU in the absence of active bleeding
• 41: Amount of blood (in ml) taken per ICU patient per day for routine blood tests (equivalent of one full blood donation every eight days)
• 75: Percentage of patients who receive at least one blood transfusion within seven days of ICU admission (40% of all ICU patients)
• $450: Cost per unit of blood in Canada (not including indirect costs associated with testing, preparation, storage, administration, reactions)
• 90: Percentage of blood that is wasted in routine lab tests
• 10: Units of blood that could be saved per 100 patients with ICU stays of more than 48 hours if the results of this study were implemented

Monkey lives with gene-edited pig kidney A macaque lived for more than two years with a kidney from a gene-edited miniature pig — one of the longest-lasting interspecies organ transplants. It raises hopes that human organ shortages could one day be alleviated by using organs from donor animals. The donor pigs received 69 gene edits to prevent immune reactions after transplantation and to keep the organ healthy. Of the 15 monkeys that received a transplant, five survived for more than one year and one of those lived for 758 days.

https://www.nature.com/articles/s41586-023-06594-4.epdf?sharing_tok...

Hair Turns Gray Due to Stuck Stem Cells

Hair-colouring stem cells must swing back and forth between their maturity states to give hair its colour.

Like human aging, stem cell maturation is considered a one-way process; once an undifferentiated stem cell goes down the path to become a specific type of cell, there is no turning back. But that does not seem to be the case with melanocyte stem cells (McSC), which give rise to cells that produce hair and skin pigments. 

In a recent study, researchers investigated McSC in hair follicles and found that depending on microenvironment cues, McSCs can fluctuate between undifferentiated and differentiated states. The researchers also found that as the hair follicle ages, a larger number of melanocyte stem cells get stuck in an undifferentiated state, losing their ability to mature and produce melanin. Published in Nature, these results not only challenge the traditional view on how stem cells differentiate, but also offer clues to why hair turns gray with aging. 

The researchers were surprised to find that McSC did not reside in an area called the bulge as previously thought, but were instead located in a compartment known as the hair germ. When the hair started to grow, the McSC transitioned to an intermediate differentiation state from which they either transformed into fully mature melanocytes at the base of the growing hair or moved up to the hair bulge where they stayed as undifferentiated cells. Then these stem cells homed back to the hair germ as the hair entered the resting phase of its growth cycle.

Once they realized that the maturation of these cells depended on their location, the team next investigated which signals within those compartments drove these changes. In the new study, the team found that nearby epithelial cells in the hair germ released Wnt ligands that mature the McSC, but these signals were suppressed in the bulge where the cells regained their undifferentiated features.

Melanocytes give hair its color, and hair pigmentation reduces with aging. So, the researchers wondered what would happen to McSC mobility in an aged hair follicle. To accelerate the aging of hair follicles, the researchers plucked mouse hair to induce regeneration of the follicles and observed McSCs over time. In aged mice, they found more of the stem cells in the bulge area rather than going back to the hair germ.

These findings suggested that as the hair follicle ages, McSC get stuck in a region where less pigment-inducing signals are present. This mechanism might explain why hair turns gray much more rapidly than it falls off.

Although scientists knew that cells could swing back and forth between their maturity states when there were tissue injuries, the study results are exciting as they reveal that dedifferentiation can also occur under a physiological condition.

Since the researchers conducted all of the experiments in mice, questions remain as to whether the same events are also seen in humans.

Sun Q, et al. Dedifferentiation maintains melanocyte stem cells in a dynamic niche. Nature. 2023;616(7958):774-782.

Rabbani P, et al. Coordinated activation of Wnt in epithelial and melanocyte stem cel.... Cell. 2011;145(6):941-955.

Research shows wildfire smoke may linger in homes long after initial blaze

Newly published research on indoor air quality  shows wildfire smoke may linger in homes long after the initial blaze has been put out or winds have shifted.

The findings, published in Science Advances, show that wildfire smoke can attach to home surfaces like carpet, drapes or counters—extending the exposure for those inside and potentially causing health problems even after an initial cleaning activity by air purifiers.

However, the research also shows that  surface cleaning—like vacuuming, dusting or mopping—can reduce exposure and limit risk. The team was able to show that the amount of smoke left on surfaces was proportional to the surface area that was cleaned. That means simple cleaning and specifically addressing large but little noticed spaces that may trap harmful compounds such as cabinets and HVAC systems could be beneficial right away.

 Jienan Li et al, The persistence of smoke VOCs indoors: partitioning, surface cleaning, and air cleaning in a smoke-contaminated house, Science Advances (2023). DOI: 10.1126/sciadv.adh8263. www.science.org/doi/10.1126/sciadv.adh8263

Targeting a coronavirus ion channel could yield new COVID-19 drugs

The genome of the SARS-CoV-2 virus encodes 29 proteins, one of which is an ion channel called E. This channel, which transports protons and calcium ions, induces infected cells to launch an inflammatory response that damages tissues and contributes to the symptoms of COVID-19.

MIT chemists have now discovered the structure of the "open" state of this channel, which allows ions to flow through. This structure, combined with the "closed" state structure that was reported by the same lab in 2020, could help scientists figure out what triggers the channel to open and close. These structures could also guide researchers in developing antiviral drugs that block the channel and help prevent inflammation.

When SARS-CoV-2 infects cells, the E channel embeds itself inside the membrane that surrounds a cellular organelle called the ER-Golgi intermediate compartment (ERGIC). The ERGIC interior has a high concentration of protons and calcium ions, which the E channel transports out of ERGIC and into the cell cytoplasm. That influx of protons and calcium leads to the formation of multiprotein complexes called inflammasomes, which induce inflammation.

Previous research has shown that when SARS-CoV-2 viruses are mutated so that they don't produce the E channel, the viruses generate much less inflammation and cause less damage to host cells.

So the E channel is an antiviral drug target now. If you can stop the channel from sending calcium into the cytoplasm, then you have a way to reduce the cytotoxic effects of the virus.

Joao Medeiros-Silva et al, Atomic Structure of the Open SARS-CoV-2 E Viroporin, Science Advances (2023). DOI: 10.1126/sciadv.adi9007. www.science.org/doi/10.1126/sciadv.adi9007

The three types of households with their typical characteristics and food waste behaviours. Credit: Trang Nguyen using Canva.com, CC BY-NC-ND

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 a fire retardant in building materials

Flu-resistant chickens
 Birds with small alterations to one gene are highly resistant to avian flu

Scientists have created the world’s first flu-resistant chickens in an advance that could pave the way for gene-edited poultry. The birds, which had small alterations to one gene, were highly resistant to avian flu, with nine in 10 birds showing no signs of infection when exposed to a typical dose of the virus.

However, infections were not completely blocked, and scientists say this would have to be achieved before genetically engineered chickens could be introduced to farms, due to the risk of the virus evolving to become more dangerous to humans.

https://www.nature.com/articles/s41467-023-41476-3

If you are not getting enough sleep, your vascular cells may be drowning in oxidants!

Several people in the world are in the same situation of sleep deprivation and habitually get only five to six hours of sleep instead of the recommended seven to eight hours.

But even a mild chronic sleep deficit may heighten the risk of developing heart disease later in life: Surveys of thousands of people have found that people who report mild but chronic sleep deficits have more heart disease later in life than people who get adequate sleep.

Published in Scientific Reports, a study of women now shows what's happening in the body during chronic mild sleep deprivation.

After just six weeks of shortened sleep, the study found, the cells that line our blood vessels are flooded by damaging oxidants. And unlike well-rested cells, sleep-restricted cells fail to activate antioxidant responses to clear the destructive molecules.

The result: cells that are inflamed and dysfunctional, an early step in the development of cardiovascular disease. This is some of the first direct evidence to show that mild chronic sleep deficits cause heart disease.

Riddhi Shah, Vikash Kumar Shah, Memet Emin, Su Gao, Rosemary V. Sampogna, Brooke Aggarwal, Audrey Chang, Marie-Pierre St-Onge, Vikas Malik, Jianlong Wang, Ying Wei, Sanja Jelic. Mild sleep restriction increases endothelial oxidative stress in female persons. Scientific Reports, 2023; 13 (1) DOI: 10.1038/s41598-023-42758-y

A theory on how gold, platinum, and other precious metals found their way into Earth's mantle

Scientists say they've hit the jackpot with some valuable new information about the story of gold.

It's a story that begins with violent collisions of large objects in space, continues in a half-melted region of Earth's mantle, and ends with precious metals finding an unlikely resting spot much closer to the planet's surface than scientists would have predicted.

Their new theory provides possible answers to lingering questions about the way gold, platinum, and other precious metals found their way to shallow pockets within Earth's mantle rather than deep in the planet's core. More broadly, the new theory offers insights into planet formation throughout the universe.

Recent research from scientists around the world has established that precious metals such as gold and platinum came to Earth billions of years ago after the early proto-Earth collided with large, moon-sized bodies in space, which left behind deposits of materials that were folded into what is today's Earth.

Aside from being valued for their scarcity, aesthetic beauty, and use in high-tech products, gold and platinum are what is known as highly "siderophile" elements. They are drawn to the element iron to such a degree that they would be expected to collect almost entirely in Earth's metallic core—either by merging directly with the metal core on impact or by sinking quickly from the mantle into the core.

By this logic, they should not have collected at or near the Earth's surface. Yet they did.

The new theory centers around a thin, "transient" region of the mantle, where the shallow part of the mantle melts and the deeper part remains solid. The researchers found that this region has peculiar dynamic properties that can efficiently trap falling metallic components and slowly deliver them to the rest of the mantle. 

Their theory posits that this delivery is still ongoing, with the remnants of the transient region appearing as "large low-shear-velocity provinces"—well-known geophysical anomalies in the deep mantle.

This transient region almost always forms when a big impactor hits the early Earth, making this new  theory quite robust.

 Jun Korenaga et al, Vestiges of impact-driven three-phase mixing in the chemistry and structure of Earth's mantle, Proceedings of the National Academy of Sciences (2023). DOI: 10.1073/pnas.2309181120

Scientists identify nature's missing evolutionary law

A paper published in the Proceedings of the National Academy of Sciences describes "a missing law of nature," recognizing for the first time an important norm within the natural world's workings.

In essence, the new law states that complex natural systems evolve to states of greater patterning, diversity, and complexity. In other words, evolution is not limited to life on Earth, it also occurs in other massively complex systems, from planets and stars to atoms, minerals, and more.

"Macroscopic" laws of nature describe and explain phenomena experienced daily in the natural world. Natural laws related to forces and motion, gravity, electromagnetism, and energy, for example, were described more than 150 years ago.

The new work presents a modern addition—a macroscopic law recognizing evolution as a common feature of the natural world's complex systems, which are characterized as follows:

• They are formed from many different components, such as atoms, molecules, or cells, that can be arranged and rearranged repeatedly
• Are subject to natural processes that cause countless different arrangements to be formed
• Only a small fraction of all these configurations survive in a process called "selection for function."

Part 1

Regardless of whether the system is living or nonliving, when a novel configuration works well and function improves, evolution occurs.

The authors' "Law of Increasing Functional Information" states that the system will evolve "if many different configurations of the system undergo selection for one or more functions."

In the case of biology, Darwin equated function primarily with survival—the ability to live long enough to produce fertile offspring.

The new study expands that perspective, noting that at least three kinds of function occur in nature.

The most basic function is stability—stable arrangements of atoms or molecules are selected to continue. Also chosen to persist are dynamic systems with ongoing supplies of energy.

The third and most interesting function is "novelty"—the tendency of evolving systems to explore new configurations that sometimes lead to startling new behaviors or characteristics.

Part 2

Life's evolutionary history is rich with novelties—photosynthesis evolved when single cells learned to harness light energy, multicellular life  evolved when cells learned to cooperate, and species evolved thanks to advantageous new behaviors such as swimming, walking, flying, and thinking.

The same sort of evolution happens in the mineral kingdom. The earliest minerals represent particularly stable arrangements of atoms. Those primordial minerals provided foundations for the next generations of minerals, which participated in life's origins. The evolution of life and minerals are intertwined, as life uses minerals for shells, teeth, and bones.

Indeed, Earth's minerals, which began with about 20 at the dawn of our solar system, now number almost 6,000 known today thanks to ever more complex physical, chemical, and ultimately biological processes over 4.5 billion years.

In the case of stars, the paper notes that just two major elements—hydrogen and helium—formed the first stars shortly after the big bang. Those earliest stars used hydrogen and helium to make about 20 heavier chemical elements. And the next generation of stars built on that diversity to produce almost 100 more elements.

Part 3