Researchers decided to investigate how the protein functioned in mice, which retain brown fat throughout their lives. They found that KLF-15 was much less abundant in white fat cells than in brown or beige fat cells.

When they then bred mice with white fat cells that lacked KLF-15, the mice converted them from white to beige. Not only could the fat cells switch from one form into another, but without the protein, the default setting appeared to be beige.

The researchers then looked at how KLF-15 exerts this influence. They cultured human fat cells and found that the protein controls the abundance of a receptor called Adrb1, which helps maintain energy balance.

Scientists knew that stimulating a related receptor, Adrb3, caused mice to lose weight. But human trials of drugs that act on this receptor have had disappointing results.
A different drug targeting the Adrb1 receptor in humans is more likely to work, according to Feldman, and it could have significant advantages over the new, injectable weight-loss drugs that are aimed at suppressing appetite and blood sugar.

This approach might avoid side effects like nausea because its activity would be limited to fat deposits, rather than affecting the brain. And the effects would be long lasting, because fat cells are relatively long-lived.
These discoveries could have a big impact on treating obesity.

Source: Journal of Clinical Investigation (2024)

https://www.jci.org/articles/view/172360

Part 2 

Scientists discover a new set of cells that control the blood-brain barrier

Researchers have discovered a new set of cells that can protect blood vessel structure in the central nervous system (CNS) known as the blood-brain barrier. Their findings have been published in the journal Science Advances.

They identified a new set of astrocytes (type of brain cells) that can control the integrity of the blood-brain barrier.

The blood-brain barrier (BBB) is a selective semi-permeable membrane between the blood and the interstitium of the brain, allowing cerebral blood vessels to regulate molecule and ion movement between the blood and the brain.

With age, or in brain disorders, the function of the blood-brain barrier is reduced.

This newly discovered subset of astrocytes expressed a protein found in bone tissue called dentin matrix protein 1 (DMP-1). These cells generate 'endfeet' and transfer mitochondria (energy generating cells) to endothelial cells which line the blood vessels of the CNS.

Reduction in the function of these astrocytes inhibited mitochondrial transfer and caused leakage of the blood-brain barrier. Mitochondrial transfer from astrocytes to blood vessel cells was identified as crucial to the maintenance of the blood-brain barrier.

Delin Liu et al, Regulation of blood-brain barrier integrity by Dmp1 -expressing astrocytes through mitochondrial transfer, Science Advances (2024). DOI: 10.1126/sciadv.adk2913

Incredible Hydrothermal Environment Discovered Deep Beneath The Ocean

A stunning new wonderland has been discovered, hidden deep beneath the ocean waves of the Arctic Circle. Off the coast of Svalbard, in Norway, more than 3,000 meters (9,842 feet) down, a field of hydrothermal vents unfolds along the Knipovich Ridge, an underwater mountain range previously thought to be fairly unremarkable. Instead, like underfloor heating, volcanic activity below the seafloor causes heat to seep through, creating havens of warmth and chemical reactions where life can gather and thrive. The field, measuring at least a kilometer in length and 200 meters in width, has been named Jøtul, for the giants of Norse mythology that live beneath mountains. In this case, the giant is Earth's internal processes, released through cracks in the seafloor. Water penetrates into the ocean floor where it is heated by magma. The overheated water then rises back to the sea floor through cracks and fissures. On its way up the fluid becomes enriched in minerals and materials dissolved out of the oceanic crustal rocks. These fluids often seep out again at the sea floor through tube-like chimneys called black smokers, where metal-rich minerals are then precipitated. Hydrothermal vent fields are some of the most interesting undersea environments. They're usually very deep beneath the ocean surface, so far down that light from the Sun can't penetrate the vast volume of water above them. At these depths, conditions are permanently dark, freezing cold, and surrounded by crushing pressures. This environment isn't exactly conducive to life, but hydrothermal vents act as strange oases. The minerals seeping out and dissolving in the water provide the basis for a food web reliant, not on photosynthesis as most life closer to the surface is, but chemosynthesis – harnessing chemical reactions for energy, rather than sunlight. These environs make for a much more dynamic and thriving deep seafloor than might be expected, giving us a clue about how life might emerge on worlds very different from our own.

https://www.nature.com/articles/s41598-024-60802-3

How insulin-triggering nutrients vary from person to person, with implications for personalized nutrition

When it comes to managing blood sugar levels, most people think about counting carbs. But new research  shows that, for some, it may be just as important to consider the proteins and fats in their diet.

The study, published in Cell Metabolism, is the first large-scale comparison of how different people produce insulin in response to each of the three macronutrients: carbohydrates (glucose), proteins (amino acids) and fats (fatty acids).

The findings reveal that production of the blood sugar-regulating hormone insulin is much more dynamic and individualized than previously thought, while showing for the first time a subset of the population who are hyper-responsive to fatty foods.

Glucose is the well-known driver of insulin, but it is surprising to see such high variability, with some individuals showing a strong response to proteins, and others to fats, which had never been characterized before.

Insulin plays a major role in human health, in everything from diabetes, where it is too low, to obesity, weight gain and even some forms of cancer, where it is too high. These findings lay the groundwork for personalized nutrition that could transform how we treat and manage a range of conditions.

For the study, the researchers conducted tests on pancreatic islets from 140 deceased male and female donors across a wide age range. The islets were exposed to each of the three macronutrients, while the researchers measured the insulin response alongside 8,000 other proteins.

Although most donors' islet cells had the strongest insulin response to carbohydrates, approximately 9% responded strongly to proteins, while another 8% of the donor cells were more responsive to fats than any other nutrient—even glucose.

This research challenges the long-held belief that fats have negligible effects on insulin release in everyone. With a better understanding of a person's individual drivers of insulin production, we could potentially provide tailored dietary guidance that would help people better manage their blood sugar and insulin levels.

The research team also examined a subset of islet cells from donors who had type 2 diabetes. As expected, these donor cells had a low insulin response to glucose. However, the researchers were surprised to see that their insulin response to proteins remained largely intact.

"This really bolsters the case that protein-rich diets could have therapeutic benefits for patients with type 2 diabetes and highlights the need for further research into protein-stimulated insulin secretion.

In the future, the researchers say it could be possible use genetic testing to determine which macronutrients are likely to trigger a person's insulin response.

 Proteomic predictors of individualized nutrient-specific insulin secretion in health and disease, Cell Metabolism (2024). DOI: 10.1016/j.cmet.2024.06.001. www.cell.com/cell-metabolism/f … 1550-4131(24)00226-2

Doctors could soon use facial temperature for early diagnosis of metabolic diseases

A colder nose and warmer cheeks may be a telltale sign of rising blood pressure. Researchers discovered that temperatures in different face regions are associated with various chronic illnesses, such as diabetes and high blood pressure. These temperature differences are not easily perceptible by one's own touch but can instead be identified using specific AI-derived spatial temperature patterns that require a thermal camera and a data-trained model.

The results appeared July 2 in the journal Cell Metabolism. With further research, doctors could one day use this simple and non-invasive approach for early detection of diseases.

The researchers had previously used 3Dfacial structure to predict people's biological age, which indicates how well the body is aging. Biological age is closely related to the risk of diseases, including cancer and diabetes. They were curious if other features of the face, such as temperature, could also predict aging rate and health status.

They 

 analyzed facial temperatures of more than 2,800 Chinese participants between the ages of 21 and 88. Then, the researchers used the information to train AI models that could predict a person's thermal age. They identified several key facial regions where the temperatures were significantly related to age and health, including the nose, eyes and cheeks.

The research team found the temperature of the nose decreases with age at a rate faster than other parts of the face, meaning people with warmer noses have a younger thermal age. At the same time, temperatures around the eyes tend to increase with age.

The team also found that people with metabolic disorders such as diabetes and fatty liver disease had faster thermal aging. They tended to have higher eye area temperatures than their healthy counterparts of the same age. People with elevated blood pressure also had higher cheek temperatures.
By analyzing participants' blood samples, the team revealed that the increase in temperatures around the eyes and cheeks was mainly because of an increase in cellular activities related to inflammation, such as repairing damaged DNAs and fighting infections. The increase in these activities led to a rise in temperatures in certain facial regions.

The thermal clock is so strongly associated with metabolic diseases that previous facial imaging models were not able to predict these conditions.
Part 1

Due to this connection, the team set out to test if exercise could influence thermal age. They asked 23 participants to jump rope for at least 800 times daily for two weeks. To the team's surprise, these participants reduced their thermal age by five years after just two weeks of exercise.

Next, the team wants to explore if they can use thermal facial imaging to predict other diseases, such as sleeping disorders or cardiovascular problems.
Applying thermal facial imaging in clinical settings holds significant potential for early disease diagnosis and intervention.

Yu et al. Thermal Face Image Analyses Reveal Quantitative Hallmarks of Aging and Metabolic Diseases, Cell Metabolism (2024). DOI: 10.1016/j.cmet.2024.05.012. www.cell.com/cell-metabolism/f … 1550-4131(24)00188-8

Treatment with a mixture of antimicrobial peptides found to impede antibiotic resistance

A common infection-causing bacteria was much less likely to evolve antibiotic resistance when treated with a mixture of antimicrobial peptides rather than a single peptide, making these mixtures a viable strategy for developing new antibiotic treatments. Researchers report these findings in a study published July 2 in PLOS Biology.

Antibiotic-resistant bacteria have become a major threat to public health. The World Health Organization estimates that 1.27 million people died directly from drug-resistant strains in 2019 and these strains contributed to 4.95 million deaths.
While bacteria naturally evolve resistance to antibiotics, misuse and overuse of these drugs has accelerated the problem, rendering many antibiotics ineffective. One emerging strategy to combat antibiotic resistance is the use of antimicrobial peptides, which are chains of amino acids that function as broad-spectrum antimicrobial compounds and are key components of the innate immune system in animals, fungi and plants.

In the new study, researchers investigated whether antimicrobial peptide mixtures synthesized in the lab could reduce the risk of the pathogen Pseudomonas aeruginosa from evolving antimicrobial resistance, compared to exposure to a single antimicrobial peptide.

They found that using antimicrobial peptide mixtures carried a much lower risk of the bacteria developing resistance. The mixtures also helped prevent the bacteria from developing cross-resistance to other antimicrobial drugs, while maintaining—or even improving—drug sensitivity.

Overall, the findings suggest that the use of antimicrobial peptide mixtures is a strategy worth pursuing in the search for new, longer-lasting treatments for bacteria.

The researchers suspect that using a cocktail of multiple antimicrobial peptides creates a larger set of challenges for bacteria to overcome, which can potentially delay the evolution of resistance, compared to traditional antibiotics. Furthermore, these cocktails can be synthesized affordably, and previous studies have shown them to be non-toxic in mice.

Bernardo Antunes et al, The evolution of antimicrobial peptide resistance in Pseudomonas aeruginosa is severely constrained by random peptide mixtures, PLoS Biology (2024). DOI: 10.1371/journal.pbio.3002692

Doctor ants: Ants too perform amputations to save injured nestmates!

Saving lives through surgery is no longer exclusive to humans. In a study published July 2 in the journal Current Biology, scientists detail how Florida carpenter ants, a common, brown species native to its namesake, selectively treat the wounded limbs of fellow nestmates—either by wound cleaning or amputation.

When experimentally testing the effectiveness of these "treatments," not only did they aid in recovery, but the research team found the ants' choice of care catered to the type of injury presented to them.

The researchers found that this mechanical care involves one of two routes. The ants would either perform wound cleaning with just their mouthparts or perform a cleaning followed by the full amputation of the leg. To select which route they take, the ants appear to assess the type of injury to make informed adjustments on how best to treat.

In this study, two types of leg injuries were analyzed, lacerations on the femur and those on the ankle-like tibia. All femur injuries were accompanied by initial cleaning of the cut by a nestmate, followed by a nestmate chewing off the leg entirely. In contrast, tibia injuries only received the mouth cleaning. In both cases, intervention resulted in ants with experimentally infected wounds having a much greater survival rate.

Femur injuries, where they always amputated the leg, had a success rate around 90% or 95%. And for the tibia, where they did not amputate, it still achieved about the survival rate of 75%.

Part1

In tibia injuries, the flow of the hemolymph was less impeded, meaning bacteria could enter the body faster. While in femur injuries the speed of the blood circulation in the leg was slowed down.

You may expect, then, if tibia damage results in faster infections, amputating the full leg would be most appropriate, but the opposite is observed. It turns out the speed at which the ants can amputate a leg makes a difference.

An ant-assisted amputation takes at least 40 minutes to complete. Experimental testing demonstrated that with tibia injuries, if the leg was not immediately removed post-infection, the ant would not survive.

"Thus, because they are unable to cut the leg sufficiently quickly to prevent the spread of harmful bacteria, ants try to limit the probability of lethal infection by spending more time cleaning the tibia wound.

The fact that the ants are able to diagnose a wound, see if it's infected or sterile, and treat it accordingly over long periods of time by other individuals—the only medical system that can rival that would be the human one.

And they can do it without studying medicine and learning surgery! It's really all innate behaviour!

Ant behaviors change based on the age of an individual, but there is very little evidence of any learning.

"When you look at the videos where you have the ant presenting the injured leg and letting the other one bite off completely voluntarily, and then present the newly made wound so another one can finish cleaning process—this level of innate cooperation  is quite striking", say the researchers.

Erik Frank et al, Wound-dependent leg amputations to combat infections in an ant society, Current Biology (2024). DOI: 10.1016/j.cub.2024.06.021. www.cell.com/current-biology/f … 0960-9822(24)00805-4

Part 2

Longest Cyclone on Record Crossed The Entire Southern Indian Ocean in 2023

Cyclone Freddy, which crossed the entire southern Indian Ocean before wreaking devastation on southeastern Africa last year, was the longest-lasting tropical cyclone ever recorded at 36 days, the UN confirmed Tuesday.

A panel of experts has been poring over the data surrounding the storm since its remarkable journey in February and March last year.

The United Nations' weather and climate agency concluded it had indeed broken the previous record.

The extreme weather evaluation committee "recognised Tropical Cyclone Freddy's duration of 36.0 days at tropical storm status or higher as the new world record for the longest tropical cyclone duration", the World Meteorological Organization (WMO) said in a statement.

• Freddy crossed the Indian Ocean basin in February-March 2023.
• Madagascar and southeastern Africa bore brunt of human and economic losses.
• Freddy was 36 days at tropical storm status or higher, beating record of John (1994)
• Freddy was 2nd longest in terms of distance travelled
• Monitoring of extremes increases understanding of weather and climate impacts.

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Bright Light at Night May Raise Type 2 Diabetes Risk, Study Suggests

The glow of a lightbulb or smartphone at night can mess with the body's circadian rhythm. Now, a new study suggests that exposure to artificial light after midnight may raise the risk of developing type 2 diabetes. The research was conducted among nearly 85,000 people, between the ages of 40 and 69, who wore devices on their wrists, day and night for one week, to track their exposure to different levels of light.

As part of the UK Biobank experiment, the health of the cohort was tracked for as long as nine years. Those volunteers who later went on to develop type 2 diabetes were more likely to have been exposed to light between 12:30 am and 6:00 am, during the week-long study period.

The results do not prove cause and effect, but they do reveal a dose-dependent relationship between brighter light in the middle of the night and the risk of a metabolic disorder, which bolsters the association.

Those participants in the top 10 percent for light exposure at night had as much as a 67 percent higher risk of developing type 2 diabetes than those in the bottom 50th percentile.

Research suggests that exposure to artificial light at night, whether it be yellow light from your reading lamp or blue light from your smartphone or TV, can make it harder to fall asleep. But even when researchers accounted for sleep patterns and duration in the current study, the results held, which suggests another mechanism is at play.
Other possible contributing factors, like a person's sex, their genetic risk for diabetes, their diet, physical activity, daylight exposure, smoking, or alcohol use, also had no impact on the results.

Advising people to avoid night light is a simple and cost-effective recommendation that may ease the global health burden of type 2 diabetes," conclude the authors of the study.
Part 1

In the past, some other observational studies have also linked artificial light at night to insulin resistance, but these experiments did not measure indoor, artificial light sources nearly as closely or for as long.

Emerging evidence in animals and humans suggests exposure to artificial light can disrupt circadian rhythms, leading to reduced glucose tolerance, altered insulin secretion, and weight gain – all of which are tied to an increased risk of metabolic disorders like type 2 diabetes.

One major limitation of the study is that researchers were not able to take into account meal times, which can have an impact on both circadian rhythms and glucose tolerance. Furthermore, some socioeconomic factors, like a person's housing situation, were accounted for at a regional, not an individual level, and only older adults were considered.

There's also the fact that individual bodies respond very differently to light, with some studies suggesting the intensity of light needed to suppress the production of melatonin, which helps regulate our circadian rhythm, can range from 6 to 350 lux.
Nevertheless, previous experiments suggest that when melatonin is disrupted and the circadian rhythm is thrown out of whack, it can lead to the pancreas secreting less insulin. This could be a contributing factor to the development of diabetes.

Far more rigorous studies are needed before scientists can truly understand how light at night impacts the circadian rhythm and what that may do, in turn, to the health of the body's metabolism.

Some studies suggest that even a weekend of camping without artificial light can help reset a person's circadian rhythm. Perhaps that's just what the doctor should order.

https://www.thelancet.com/journals/lanepe/article/PIIS2666-7762(24)00110-8/fulltext

Part 2

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Strategies that could stop cats from scratching your furniture, according to science

Many cat owners are familiar with torn cushions, carpets, and couches. The feline instinct to scratch is innate, but is often perceived as a behavioral problem by cat owners, and sometimes leads to interventions that are not cat-friendly.

Now, an international team of researchers has investigated which factors influence undesired scratching behavior in domestic cats. The team has published its findings in Frontiers in Veterinary Science.

Scientists found that  certain factors—such as the presence of children at home, personality traits of cats, and their activity levels—significantly impact the extent of scratching behaviour.

The researchers' results showed that there are several factors that influence cats' scratching behaviour. They saw a clear link between certain environmental and behavioural factors and increased scratching behaviour in cats.

Specifically, the presence of children in the home as well as high levels of play and nocturnal activity significantly contribute to increased scratching. Cats described as aggressive or disruptive also exhibited higher levels of scratching.

Stress, the researchers said, was found to be a leading reason for unwanted scratching. For example, the presence of children, particularly while they are small, might amplify stress and be one of several causes that can make felines stress-scratch. The link between increased scratching and children in the home, however, is not fully understood and further study is needed. Another factor that could also be connected to stress is playfulness. When cats play for a long time, their stress levels can rise because of the uninterrupted stimulation.

Part 1

While some factors that favor scratching—such as the cat's personality or the presence of children—cannot be changed, others can, the researchers said. Placing scratch posts in areas the cat frequently passes or near to their preferred resting spot, or the use of pheromones, for example, can lessen cats' scratching on furniture.

Providing safe hiding places, elevated observation spots, and ample play opportunities can also help alleviate stress and engage the cat in more constructive activities.

The key is to establish multiple short play sessions that mimic successful hunting scenarios. These play sessions are more likely to sustain cats' interest and reduce stress, which ultimately can reduce excessive scratching on furniture. They can also foster the bond between cats and their caretakers, the researchers say.

Understanding the underlying emotional motivations of scratching behavior, such as frustration, which seem to be linked to personality traits and environmental factors, allows caregivers to address these issues directly.

Evaluating Undesired Scratching in Domestic Cats: A Multifactorial Approach to Understand Risk Factors, Frontiers in Veterinary Science (2024). DOI: 10.3389/fvets.2024.1403068

Part 2

Scientists discover PVP-037, a potent vaccine adjuvant

Many vaccines are only partially effective, have waning efficacy, or do not work well in the very young or the very old. For several years researchers have tried improving vaccines by adding compounds known as adjuvants to boost vaccine recipients' immune responses.

Now they've identified a new and promising adjuvant of their own, dubbed PVP-037. The finding is published in Science Advances.

In principle, this compound can be added to any vaccine to enhance its action.

 Adjuvants are like rocket fuel for the immune system. PVP-037 is one of the most active adjuvants scientists 've discovered, and they think it induces a greater, more durable, and broader immune response to vaccines.

The researchers began by screening more than 200,000 small molecules from a Harvard Medical School library in human immune cells—specifically, in primary peripheral blood mononuclear cells, obtained from donors and cultured in their own plasma using a method developed within the Precision Vaccines Program. This yielded about 25 confirmed hits, with PVP-037 being the most active.

PVP-037 belongs to a family of molecules called imidazopyrimidines, which the study found to be active immunomodulators. PVP-037 and its analogs target the innate immune system, stimulating the pattern-recognition receptors TLR7 and TLR8 on antigen-presenting cells such as monocytes and dendritic cells.

An optimized version of PVP-037 demonstrated broad innate immune activation in the donor immune cells, inducing NF-κB and production of TNF and other cytokines, signaling molecules that rally a wider immune response. Notably, PVP-037 did not provoke such a response in cultured cell lines. In live mice, it enhanced antibody responses against influenza and SARS-CoV-2 vaccine proteins.

In addition to inducing robust immune activity, the compound is stable, easy to work with, and lends itself to chemical optimization for medical use. It can be formulated in most standardly-used drug delivery systems, such as oil-in-water emulsions.

 Dheeraj Soni et al, From Hit to Vial: Precision discovery and development of an imidazopyrimidine TLR7/8 agonist adjuvant formulation, Science Advances (2024). DOI: 10.1126/sciadv.adg3747. www.science.org/doi/10.1126/sciadv.adg3747

Fighting COVID-19 with a cancer drug: A new approach to preventing irreversible organ damage in infectious diseases

Twelve years ago, cancer researchers identified a molecule that helps cancer cells survive by shuttling damaging inflammatory cells into tumor tissue. In new research, they show that the same molecule does the same thing in lung tissue infected with COVID-19—and that the molecule can be suppressed with a repurposed cancer drug.

The work, published in Science Translational Medicine, represents a new approach to preventing irreversible organ damage in infectious diseases like COVID-19 and methicillin-resistant Staphylococcus aureus (MRSA).

The two key players in this scenario are inflammatory cells called myeloid cells, and an enzyme called PI3K gamma (phosphatidylinositol 3,4,5-kinase gamma). Myeloid cells belong to our innate immune system—the immunity we're born with before we're exposed to pathogens in the environment—and work very quickly to kill deadly agents like SARS-CoV-2, the virus that causes COVID-19.

This work shows that drugs that can prevent the recruitment of damaging myeloid cells into tissues that are infected with severe agents like COVID-19 or MRSA have a significant benefit in preserving tissue function if given early enough in an infection.

Most other COVID-19 drugs target the virus, either preventing infection in the first place or preventing the virus from making more of itself after infection. The current approach targets the host, keeping the immune system from overreacting or fibers building up in the lungs.

Myeloid cells protect us, but they can also do a lot of damage. 

If you have a little infection, myeloid cells come in, kill bacteria, release alerts that recruit even more potent killer immune cells, and produce substances that can heal the damage. But if you get an infection that's too strong, you get overproduction of these alert signals, and the substances they release to kill these infective agents can also kill yourself. That's what happens in COVID-19.

Part 1

PI3K gamma promotes the movement of myeloid cells into cancerous tissues, as found in the team's work with cancer twelve years ago. In the current work, they show that PI3K gamma also helps move myeloid cells into tissues infected with SARS-CoV-2.

That led them to reason that a cancer drug that inhibits PI3K gamma, called eganelisib, might be effective in suppressing inflammation in COVID-19 by suppressing PI3K gamma's ability to move myeloid cells into infected tissue.

Using a combination of bulk RNA sequencing and bioinformatics, the scientists analyzed tissues from humans and mice to see how SARS-CoV-2 changed the cellular and molecular makeup of infected tissues. They then treated the tissue with eganelisib to see if suppressing PI3K gamma made a difference.
The researchers sequenced COVID-19 patient lung tissue and showed that when patients have COVID-19, a lot of their lung cells are killed and there's a huge increase in myeloid cells. They also found the same thing in infected mice.

When they treated with the drug, they showed that eganelisib prevents entry of myeloid cells into tissue so they can't do all that damage. Further studies will determine if it can actually reverse damage. The team also had the same results in mice infected with MRSA.

Ryan Shepard et al, PI3Kγ inhibition circumvents inflammation and vascular leak in SARS-CoV-2 and other infections, Science Translational Medicine (2024). DOI: 10.1126/scitranslmed.adi6887. www.science.org/doi/10.1126/scitranslmed.adi6887

Part 2

Human crying stresses out dogs more than pigs

Some animals can have babies without a sexual partner

Science explains how

A boa constrictor in the U.K. gave birth to 14 babies—without a mate.

 The result of a secret rendezvous? Probably not. Females of species have the ability to reproduce asexually, without sperm from a male. The process is called parthenogenesis, from the Greek words for "virgin" and "birth."

Some plants and insects can do it, as well as some amphibians, reptiles, birds and fish. A stingray named Charlotte that was thought to have become pregnant by this method died this week at an aquarium in North Carolina, though she never delivered and it is unclear if she was ever pregnant.

Some wasps, crustaceans and lizards reproduce only through parthenogenesis. But in other species it's rare and usually only observed in captivity. Scientists have a good idea how it happens, though they aren't clear why it happens.

A female's egg fuses with another cell, often a cell leftover from a process that allows the female to create the egg. That cell, known as a polar body, gives the egg the genetic information it would normally get from sperm. The cell starts dividing and that leads to the creation of an embryo.

The snake, a 6-foot, 13-year-old Brazilian Rainbow Boa named Ronaldo, gave birth last week after having no contact with any other snakes for at least nine years, according to the City of Portsmouth College, which kept the snake.

AP

Re-engineering cancerous tumors to self-destruct and kill drug-resistant cells

Treating cancer can sometimes feel like a game of Whac-A-Mole. The disease can become resistant to treatment, and clinicians never know when, where and what resistance might emerge, leaving them one step behind. But a team of researchers has found a way to reprogram disease evolution and design tumors that are easier to treat.

They created a modular genetic circuit that turns cancer cells into a "Trojan horse," causing them to self-destruct and kill nearby drug-resistant cancer cells. Tested in human cell lines and in mice as proof of concept, the circuit outsmarted a wide range of resistance.

The findings were published today, July 4, in the journal Nature Biotechnology. The researchers also filed a provisional application to patent the technology described in the paper.

Selection gene drives are a powerful new paradigm for evolution-guided anticancer therapy.The idea that we can use a tumor's inevitability of evolution against it is an excellent strategy.

Newer personalized cancer medicines often fail, not because the therapeutics aren't good, but because of cancer's inherent diversity and heterogeneity. Even if a frontline therapy is effective, resistance eventually develops and the medication stops working, allowing the cancer to return.

Clinicians then find themselves back at square one, repeating the process with a new drug until resistance emerges again. The cycle escalates with each new treatment until no further options are available.

You are dealing with an unpredictable opponent. You don't know what is going to be the best drug to treat the tumor. You're always on your back foot, unprepared.

The researchers wondered if, instead, they could get one step ahead. Could they potentially eliminate resistance mechanisms before the cancer cells have a chance to evolve and pop up unexpectedly? Could they force a specific "mole" to pop out on the board, one that they prefer and are prepared to fight?
What started as a thought experiment is proving to work. The team created a modular circuit, or dual-switch selection gene drive, to introduce into non-small lung cancer cells with an EGFR gene mutation. This mutation is a biomarker that existing drugs on the market can target.
Part1

The circuit has two genes, or switches. Switch one acts like a selection gene, allowing the researchers to turn drug resistance on and off, like a light switch. With switch one turned on, the genetically modified cells become temporarily resistant to a specific drug, in this case, to a non-small lung cancer drug.

When the tumor is treated with the drug, the native drug-sensitive cancer cells are killed off, leaving behind the cells modified to resist and a small population of native cancer cells that are drug-resistant. The modified cells eventually grow and crowd out the native resistant cells, preventing them from amplifying and evolving new resistance.
The resulting tumor predominantly contains genetically modified cells. When switch one is turned off, the cells become drug-sensitive again. Switch two is the therapeutic payload. It contains a suicide gene that enables the modified cells to manufacture a diffusible toxin that's capable of killing both modified and neighboring unmodified cells.

It not only kills the engineered cells, but it also kills the surrounding cells, namely the native resistant population.
That's critical. That's the population you want to get rid of so that the tumor doesn't grow back.
The team first simulated the tumor cell populations and used mathematical models to test the concept. Next, they cloned each switch, packaging them separately into viral vectors and testing their functionality individually in human cancer cell lines. They then coupled the two switches together into a single circuit and tested it again. When the circuit proved to work in vitro, the team repeated the experiments in mice.

However, the team didn't just want to know that the circuit worked; they wanted to know it could work in every way. They stress tested the system using complex genetic libraries of resistance variants to see if the gene drive could function robustly enough to counter all the genetic ways that resistance could occur in the cancer cell populations.
And it worked: Just a handful of engineered cells can take over the cancer cell population and eradicate high levels of genetic heterogeneity. It's one of the biggest strengths of the paper, conceptually and experimentally.
The beauty is that they're able to target the cancer cells without knowing what they are, without waiting for them to grow out or resistance to develop because at that point it's too late.
The researchers are currently working on how to translate this genetic circuit so that it can be delivered safely and selectively into growing tumors and eventually metastatic disease.

 Programming tumor evolution with selection gene drives to proactively combat drug resistance, Nature Biotechnology (2024). DOI: 10.1038/s41587-024-02271-7. www.nature.com/articles/s41587-024-02271-7

Part 2

Reversing chemotherapy resistance in pancreatic cancer

Pancreatic cancer is a particularly aggressive and difficult-to-treat cancer, in part because it is often resistant to chemotherapy. Now, researchers  have revealed that this resistance is related to both the physical stiffness of the tissue around the cancerous cells and the chemical makeup of that tissue. Their work, published on July 4 in Nature Materials, shows that this resistance can be reversed and reveals potential targets for new pancreatic cancer treatments.

They found that stiffer tissue can cause pancreatic cancer cells to become resistant to chemotherapy, while softer tissue made the cancer cells more responsive to chemotherapy.

The researchers focused their efforts on pancreatic ductal adenocarcinoma, a cancer that starts in the cells lining the ducts of the pancreas and accounts for 90% of pancreatic cancer cases. In these cancers, the network of materials between the cells, known as the extracellular matrix, becomes notably stiffer. Scientists have theorized that this stiff material acts as a physical block, stopping chemotherapy drugs from reaching cancerous cells, but treatments based on this idea have not been effective in humans.

The researchers worked to develop a new system to study these changes to the extracellular matrix and better understand their impact on pancreatic cancer cells. They designed three-dimensional materials that mimicked the biochemical and mechanical properties of both pancreatic tumors and healthy pancreas tissues, and used them to culture cells from pancreatic cancer patients.

They  created a designer matrix that would allow us to test the idea that these cancerous cells might be responding to the chemical signals and mechanical properties in the matrix around them.

Part 1

Using their new system, the researchers selectively activated certain types of receptors in the cancerous cells and adjusted the chemical and physical properties of their designer matrix. They found that pancreatic cancer needed two things to become resistant to chemotherapy: a physically stiff extracellular matrix and high amounts of hyaluronic acid—a polymer that helps stiffen the extracellular matrix and interacts with cells through a receptor called CD44.
Initially, the pancreatic cancer cells in a stiff matrix full of hyaluronic acid responded to chemotherapy. But after some time in these conditions, the cancerous cells became resistant to chemotherapy—they made proteins in the cell membrane that could quickly pump out chemotherapy drugs before they could take effect. The researchers found that they could reverse this development by moving the cells to a softer matrix (even if it was still high in hyaluronic acid) or blocking the CD44 receptor (even if the matrix was still stiff).

They could revert the cells back to a state where they are sensitive to chemotherapy. This suggests that if they can disrupt the stiffness signaling that's happening through the CD44 receptor, we could make patients' pancreatic cancer treatable by normal chemotherapy.

Other cancers can be affected by mechanical properties of the extracellular matrix, but these interactions typically work through a different class of receptors called integrins.

The researchers showed that pancreatic cancer cells weren't really using integrin receptors at all in our materials. That's important, because if you want to design a drug to resensitize patient cells to chemotherapy, you need to know which biological pathway to interfere with.

Engineered matrices reveal stiffness-mediated chemoresistance in patient-derived pancreatic cancer organoids, Nature Materials (2024). DOI: 10.1038/s41563-024-01908-x

Researchers identify unknown signaling pathway in the brain responsible for migraine with aura

A previously unknown mechanism by which proteins from the brain are carried to a particular group of sensory nerves causes migraine attacks, a new study shows. This may pave the way for new treatments for migraine and other types of headaches.

In around a fourth of all migraine patients, headache attacks are preceded by aura—symptoms from the brain such as temporary visual or sensory disturbances preceding the migraine attack by 5–60 minutes.

While we know with some certainty why patients experience aura, it has been a bit of a mystery why they get headaches, and why migraines are one-sided, until now.

A new study in mice conducted by researchers  is the first to demonstrate that proteins released from the brain during migraine with aura are carried with cerebrospinal fluid to the pain-signaling nerves responsible for headaches.

The researchers have discovered that these proteins activate a group of sensory nerve cell bodies at the base of the skull, the so-called trigeminal ganglion, which can be described as a gateway to the peripheral sensory nervous system of the skull.

At the root of the trigeminal ganglion, the barrier that usually prevents substances from entering the peripheral nerves is missing, and this enables substances in the cerebrospinal fluid to enter and activate pain-signaling sensory nerves, resulting in headaches.

The research results  results suggest that they have identified the primary channel of communication between the brain and the peripheral sensory nervous system. It is a previously unknown signaling pathway important for the development of migraine headache, and it might be associated with other headache diseases too.

The peripheral nervous system consists of all the nerve fibers responsible for communication between the central nervous system—the brain and spinal cord—and the skin, organs and muscles. The sensory nervous system, which is part of the peripheral nervous system, is responsible for communicating information about e.g. touch, itching and pain to the brain.

The study results offer insight into why migraine is usually one-sided. 

Most patients experience one-sided headaches, and this signaling pathway can help explain why. This study of how proteins from the brain are transported shows that the substances are not carried to the entire intracranial space, but primarily to the sensory system in the same side, which is what causes one-sided headaches.

The study was conducted on mice, but also included MR scans of the human trigeminal ganglion, and according to the scientists, there is every indication that the function of the signaling pathway is the same in mice and humans, and that in humans too, the proteins are carried by cerebrospinal fluid.

Martin Kaag Rasmussen et al, Trigeminal ganglion neurons are directly activated by influx of CSF solutes in a migraine model, Science (2024). DOI: 10.1126/science.adl0544

Phage viruses, used to treat antibiotic resistance, gain advantage by cutting off competitors' reproduction ability

Curious bits of DNA tucked inside genomes across all kingdoms of life historically have been disregarded since they don't seem to have a role to play in the competition for survival, or so researchers thought.

These DNA pieces came to be known as "selfish genetic elements" because they exist, as far as scientists could tell, to simply reproduce and propagate themselves, without any benefit to their host organisms. They were seen as genetic hitchhikers that have been inconsequentially passed from one generation to the next.

Research conducted by scientists at the University of California San Diego has provided fresh evidence that such DNA elements might not be so selfish after all. Instead, they now appear to factor considerably into the dynamics between competing organisms.

Publishing in the journal Science, researchers in the School of Biological Sciences studied selfish genetic elements in bacteriophages (phages), viruses that are considered the most abundant organisms on Earth. To their surprise, researchers found that selfish genetic elements known as "mobile introns" provide their virus hosts with a clear advantage when competing with other viruses: Phages have weaponized mobile introns to disrupt the ability of competing phage viruses to reproduce.

This is the first time a selfish genetic element has been demonstrated to confer a competitive advantage to the host organism it has invaded.

Understanding that selfish genetic elements are not always purely 'selfish' has wide implications for better understanding the evolution of genomes in all kingdoms of life.

Erica A. Birkholz et al, An intron endonuclease facilitates interference competition between coinfecting viruses, Science (2024). DOI: 10.1126/science.adl1356. www.science.org/doi/10.1126/science.adl1356

Cool roofs outperform green roofs in urban climate modeling study

Painting roofs white or covering them with a reflective coating would be more effective at cooling cities than vegetation-covered "green roofs," street-level vegetation or solar panels, finds a new study  by  researchers.

Conversely, extensive use of air conditioning would warm the outside environment by as much as 1 degree C in a dense city center, the researchers found.

The research, published in Geophysical Research Letters, used a three-dimensional urban climate model of Greater London to test the thermal effects of different passive and active urban heat management systems, including painted "cool roofs," rooftop solar panels, green roofs, ground level tree vegetation and air conditioning during the two hottest days of the summer of 2018.

It found that if adopted widely throughout London, cool roofs could reduce outdoor temperatures across the city, on average, about 1.2 degrees C, and up to 2 degrees C in some locations. Other systems, such as extensive street-level vegetation or solar panels would provide a smaller net cooling effect, only about 0.3 degrees C on average across London, though they offer other environmental benefits. Similarly, while green roofs offer benefits like water drainage and wildlife habitats, their net cooling effect on the city was found to be negligible on average.

Air conditioning, which transfers heat from within buildings to the outside, would warm the outdoor urban environment by about 0.15 degrees C for the city overall, but by as much as 1 degree C in dense central London. The researchers also found that the increase in the distribution of air conditioning units in their model could be entirely powered by photovoltaic solar panels if they were similarly installed to their fullest extent.

To gauge the potential full effect of each method, the team modeled each one as though they had been as widely adopted as theoretically feasible across housing, commercial and industrial buildings throughout Greater London.

The researchers  comprehensively tested multiple methods that cities like London could use to adapt to and mitigate warming temperatures, and found that cool roofs were the best way to keep temperatures down during extremely hot summer days. Other methods had various important side benefits, but none were able to reduce outdoor urban heat to nearly the same level.

 Cool roofs could be most effective at reducing outdoor urban temperatures in London compared with other roof top and vegetation interventions: a mesoscale urban climate modelling study, Geophysical Research Letters (2024). DOI: 10.1029/2024GL109634

Air pollution drives 7% of deaths in big Indian cities: Study

More than seven percent of all deaths in 10 of India's biggest cities are linked to air pollution, a large study said recently, leading researchers to call for action to save tens of thousands of lives a year.

Smog-filled Indian cities including the capital Delhi suffer from some of the world's worst air pollution, choking the lungs of residents and posing a rising threat to health still being revealed by researchers.

For the new study, an Indian-led team looked at the levels of cancer-causing microparticles known as PM2.5 pollutants in the cities of Ahmedabad, Bengaluru, Chennai, Delhi, Hyderabad, Kolkata, Mumbai, Pune, Shimla and Varanasi.

From 2008 to 2019, more than 33,000 deaths a year could be attributed to PM2.5 exposure above the World Health Organization's recommendation of 15 micrograms per cubic meter, the study said.

That represents 7.2 percent of the recorded deaths in those cities during that period, according to the study in The Lancet Planetary Health journal.

India's capital Delhi was the worst offender, with 12,000 annual deaths linked to air pollution -- or 11.5 percent of the total.

But even cities where air pollution is not thought to be as bad -- such as Mumbai, Kolkata and Chennai -- had high death rates, the researchers emphasized.

They called for India's air quality standards to be toughened.

The country's current recommendation is 60 micrograms of PM2.5 per cubic meter, which is four times higher than the WHO's guidelines.

Lowering and enforcing the limit "will save tens of thousands of lives per year", say the researchers. 

"Methods for controlling pollution exist and are used elsewhere. They urgently need to be applied in India," they said in a statement.

The WHO says that almost everyone on Earth breathes in more than the recommended amount of air pollution, which can trigger strokes, heart disease, lung cancer and other respiratory diseases.

Jeroen de Bont et al, Ambient air pollution and daily mortality in ten cities of India: a causal modelling study, The Lancet Planetary Health (2024). DOI: 10.1016/S2542-5196(24)00114-1

Health study illustrates the interconnectedness of humans and wildlife

According to a growing body of evidence, including a recent study, the seemingly separate fields of health sciences and conservation are inextricably linked.

The study, published in the journal Environmental Science & Technology, measured lead levels in the blood of house sparrows (Passer domesticus) in Australian mining towns to accurately predict lead levels in the blood of children living in the same areas.

It shows that wildlife and human health are so intimately linked that when something like lead, which we know is a toxin, gets out into the environment and affects wildlife, it's also affecting people.

The study illustrates the growing relevance of the One Health concept, coalescing aspects of public health, veterinary health and conservation.

Max M. Gillings et al, House Sparrows as Sentinels of Childhood Lead Exposure, Environmental Science & Technology (2024). DOI: 10.1021/acs.est.4c00946

These oldest inhabited termite mounds have been active for 34,000 years

Scientists in South Africa have been stunned to discover that termite mounds that are still inhabited in an arid region of the country are more than 30,000 years old, meaning they are the oldest known active termite hills.

Some of the mounds near the Buffels River in Namaqualand were estimated by radiocarbon dating to be 34,000 years old, according to the researchers from Stellenbosch University.

Some fossilized termite mounds have been discovered dating back millions of years. The oldest inhabited mounds before this study were found in Brazil and are around 4,000 years old. They are visible from space.

 M.L. Francis et al, Calcareous termite mounds in South Africa are ancient carbon reservoirs, Science of The Total Environment (2024). DOI: 10.1016/j.scitotenv.2024.171760

Caterpillars pass down food preferences to offspring through blood

Many caterpillars are known for their specific food preferences, which they bring with them when they morph into butterflies. For instance, the monarch butterfly only feeds on milkweed plants, while the Lime butterfly feeds on lime leaves. Despite deriving from a common ancestral species, these unique diet preferences are a point of interest for researchers.

In an earlier study by researchers, they demonstrated that when caterpillars fed on leaves outside of their usual diet, they would prefer the smell of that type of plant after a few days. Remarkably, these caterpillars also passed on the acquired smell preference to their offspring.

Such a phenomenon is also seen in nature when caterpillars find themselves on a new food plant when the female butterfly lays eggs on the wrong plant by mistake. The new plant is edible but has a new smell, the caterpillars will learn to prefer this new smell and pass this preference on to their offspring.

This type of inheritance may facilitate host switching and ultimately the formation of new species, each with their own food preferences.

 V. Gowri et al, Haemolymph transfusions transfer heritable learned novel odour preferences to naive larvae of Bicyclus anynana butterflies, Biology Letters (2024). DOI: 10.1098/rsbl.2023.0595

Researchers identify 'first responder' cells in pancreas crucial for blood sugar control

How does our body control blood sugar so precisely?

Researchers found a special group of "first responder" cells in the pancreas that are crucial for triggering blood sugar response.

Their findings were published in the journal Science Advances.

Our bodies need to keep blood sugar levels just right. Too high or too low can be dangerous. This balance is disturbed in diabetes, leading to serious health issues. Beta cells in the pancreas manage this balance by releasing insulin when blood sugar levels rise.

Understanding how beta cells work and coordinate the response to rising blood sugar can ultimately help develop better treatments for diabetes.

To understand the work of the pancreas, the research team turned to zebrafish. This small tropical fish has a pancreas that works similarly to a human one. At the same time, it offers a huge advantage. Researchers can use transparent fish that have no pigment whatsoever and observe the pancreas at work in real-time in the living fish.

The group discovered that a small group of beta cells are more sensitive to sugar levels than the others. These cells respond to glucose quicker than the rest of the cells, so the research  team referred to them as "first responder" cells. They initiate the glucose response, which is followed by the remaining "follower cells."

The team wanted to test if first responders are necessary for the follower cells to respond to glucose.

Using transparent fish, the  group took advantage of optogenetics, a modern light-based technology that allows to turn single cells on or off with a beam of light.

Turning off the first responder cells lowered the response to the blood sugar of the follower cells. At the same time, when the first responders were selectively activated, the response of the follower cells was enhanced.

The first responders lie at the top of the beta cell hierarchy when it comes to control of the sugar response. Interestingly, only about 10% of the beta-cells act as first responders. It suggests that this small population of cells serves as a control centre for regulating the activity of the rest of the beta cells.

To find out what makes the first responder cells unique, the researchers compared the gene expression of highly glucose-sensitive beta cells to those that are less sensitive. They found that first responders are involved in vitamin B6 production. The first responder cells express a key enzyme involved in transforming the inactive form of dietary vitamin B6 into the form that is active in the cells.

Part1

The researchers turned off the vitamin B6 production in both zebrafish and mouse pancreas. The ability of the beta cells to respond to high blood sugar was dramatically reduced in both species.

This indicates that vitamin B6 plays an evolutionarily conserved role in the response to glucose. It is possible that the first responders produce and supply Vitamin B6 to the rest of the beta cells to regulate their activity.
We now know there are specific cells that start the glucose response and that Vitamin B6 is essential for this process.
Vitamin B6 serves as a cofactor for more than a hundred essential enzymes that play critical roles in the cells, ranging from the control of cellular respiration to neurotransmitter production.

There is actually a body of research that shows a correlation between low levels of vitamin B6 and incidence of metabolic disease and type 2 diabetes.
Understanding how Vitamin B6 regulates the beta cells in the pancreas could lead to new insights into the pathology of diabetes and ultimately to new treatments.

Luis Fernando Delgadillo-Silva et al, Optogenetic β cell interrogation in vivo reveals a functional hierarchy directing the Ca 2+ response to glucose supported by vitamin B6, Science Advances (2024). DOI: 10.1126/sciadv.ado4513

Part 2

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Key mechanisms identified for regeneration of neurons

Neurological disorders, such as trauma, stroke, epilepsy, and various neurodegenerative diseases, often lead to the permanent loss of neurons, causing significant impairments in brain function. Current treatment options are limited, primarily due to the challenge of replacing lost neurons.

Direct neuronal reprogramming, a complex procedure that involves changing the function of one type of cell into another, offers a promising strategy.

In cell culture and in living organisms, glial cells—the non-neuronal cells in the central nervous system—have been successfully transformed into functional neurons. However, the processes involved in this reprogramming are complex and require further understanding. This complexity presents a challenge, but also a motivation, for researchers in the field of neuroscience and regenerative medicine.

Two research teams now explored the molecular mechanisms at play when glial cells are converted to neurons by a single transcription factor.

The findings are published in the journal Nature Neuroscience.

Specifically, the researchers focused on small chemical modifications in the epigenome. The epigenome helps control which genes are active in different cells at different times. For the first time, the teams have now shown how coordinated the epigenome rewiring is, elicited by a single transcription factor.

Using novel methods in epigenome profiling, the researchers identified that a posttranslational modification of the reprogramming neurogenic transcription factor Neurogenin2 profoundly impacts the epigenetic rewiring and neuronal reprogramming. However, the transcription factor alone is not enough to reprogram the glial cells.

In an important discovery, the researchers identified a novel protein, the transcriptional regulator YingYang1, as a key player in this process. YingYang1 is necessary to open up the chromatin for reprogramming, to which end it interacts with the transcription factor.

The protein YingYang1 is crucial for achieving the conversion from astrocytes to neurons. 

These findings are important to understand and improve reprogramming of glial cells to neurons, and thus bring us closer to therapeutic solutions.

Allwyn Pereira et al, Direct neuronal reprogramming of mouse astrocytes is associated with multiscale epigenome remodeling and requires Yy1, Nature Neuroscience (2024). DOI: 10.1038/s41593-024-01677-5

High ambient temperature in pregnancy associated with childhood leukemia

As climate change warms the planet, high ambient temperatures are expected to be more common and intense over the coming decades  worldwide.

Researchers  have studied how rising temperatures adversely affect human health. A study appearing in  journal finds that exposure to high ambient temperatures during pregnancy can have detrimental impact on the health of the offspring.

This is the first study that directly evaluates the association between hot temperatures during pregnancy and the risk of cancer in children.

This study is adding to a growing body of literature that underscores that high ambient temperature not only has immediate health effects, but also may be a cause of future chronic diseases.

Tormod Rogne et al, High ambient temperature in pregnancy and risk of childhood acute lymphoblastic leukaemia: an observational study, The Lancet Planetary Health (2024). DOI: 10.1016/S2542-5196(24)00121-9

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Study explores the link between stock market fluctuations and emergency room visits

The advent of computerized trading and fintech platforms has made investing in stocks easier and more accessible to individuals worldwide. This has led to an increase in stock market participation in many countries.

As a result of this spike in investments, fluctuations in the stock market can have a significant effect on the finances of numerous individuals and their families.

Drastic changes in wealth or financial difficulties resulting from these stock market fluctuations could potentially also affect the mental and physical health of investors. In fact, some recent reports have found a correlation between stock market fluctuations and specific physical and psychological issues.

Researchers at the National University of Singapore, Jinan University, Peking University and Sun Yat-sen University recently explored this potential link further, focusing on the relationship between stock market fluctuations and stress-related emergency room visits in China. Their findings, published in Nature Mental Health, unveiled a trend marked by greater visits to emergency rooms by individuals experiencing stress-related mental health issues during periods of stock market volatility.

To study the relationship between stock market fluctuations and emergency room visits in China, this team of researchers statistically analyzed data collected at the largest hospitals in Beijing over the course of three years, spanning from 2009 to 2012. This data, which was specific to emergency room visits for reasons potentially related to stress, was analyzed in conjunction with stock market trends in China during the same period.

Overall, the results of the analyses run by the researchers suggest that stock market shocks had immediate effects on cardiovascular diseases and mental health disorders in the period ranging between 2009 and 2012, as volatility in stock markets was linked to more visits to the emergency room for these stress-related physical and mental issues. As the data used by the researchers was over a decade old, they highlighted the need for additional studies using newer medical and financial data.
The health effects are highly nonlinear, instantaneous and more salient for older people and males.

Sumit Agarwal et al, Associations between stock market fluctuations and stress-related emergency room visits in China, Nature Mental Health (2024). DOI: 10.1038/s44220-024-00267-5

 Fungi and lichens pose deadly threat to 5,000-year-old rock art

The Negev desert of southern Israel is renowned for its unique rock art. Since at least the third millennium BCE, the hunters, shepherds, and merchants who roamed the Negev have left thousands of carvings (petroglyphs) on the rocks. These figures are mostly cut into desert varnish: a thin black coating on limestone rock, which forms naturally. Many represent animals such as ibexes, goats, horses, donkeys, and domestic camels, but abstract forms also occur.

Researchers find a way to protect microbes from extreme conditions

Microbes that are used for health, agricultural, or other applications need to be able to withstand extreme conditions, and ideally the manufacturing processes used to make tablets for long-term storage. Researchers have now developed a new way to make microbes hardy enough to withstand these extreme conditions.

Their method involves mixing bacteria with food and drug additives from a list of compounds that the FDA classifies as "generally regarded as safe." The researchers identified formulations that help to stabilize several different types of microbes, including yeast and bacteria, and they showed that these formulations could withstand high temperatures, radiation, and industrial processing that can damage unprotected microbes.

In an even more extreme test, some of the microbes recently returned from a trip to the International Space Station, coordinated by Space Center Houston, the researchers are now analyzing how well the microbes were able to withstand those conditions.

What this project was about is stabilizing organisms for extreme conditions. Scientists are really thinking about a broad set of applications, whether it's missions to space, human applications, or agricultural uses.

Synthetic extremophiles via species-specific formulations improve microbial therapeutics, Nature Materials (2024). DOI: 10.1038/s41563-024-01937-6

Scientists visualize magnetic fields at atomic scale with holography electron microscope

A research team  has achieved a major breakthrough in the observation of magnetic fields at unimaginably small scales.

The team used Hitachi's atomic-resolution holography electron microscope—with a newly developed image acquisition technology and defocus correction algorithms—to visualize the magnetic fields of individual atomic layers within a crystalline solid.

Many advances in electronic devices, catalysis, transportation, and energy generation have been made possible by the development and adoption of high-performance materials with tailored characteristics. Atom arrangement and electron behavior are among the most critical factors that dictate a crystalline material's properties.

Notably, the orientation and strength of magnetic fields right at the interface between different materials or atomic layers are particularly important, and often help explain many peculiar physical phenomena.

Toshiaki Tanigaki et al, Electron holography observation of individual ferrimagnetic lattice planes, Nature (2024). DOI: 10.1038/s41586-024-07673-w

Scientists identify thousands of high-risk cancer gene variants

More than 5,000 genetic variants that enable certain cancers to thrive have been identified by scientists, along with a potential therapeutic target to treat or even prevent these cancers from developing.

Researchers from the Wellcome Sanger Institute, and their collaborators at The Institute of Cancer Research, London, and the University of Cambridge assessed the health impact of all possible genetic changes in the "tumor protection" gene, BAP1. They found around a fifth of these possible changes were pathogenic, significantly increasing the risk of developing cancers of the eye, lung lining, brain, skin, and kidney.

The findings, published recently (5 July) in Nature Genetics, are freely available so that they can be immediately used by doctors to help diagnose patients and choose the most effective therapies for them. Importantly, as all possible variants were assessed, the findings benefit individuals from diverse ethnic backgrounds, who have historically been underrepresented in genetics research.

The team also uncovered a link between certain disruptive BAP1 variants and higher levels of IGF-1, a hormone and growth factor. This discovery opens the door to developing new drugs that could inhibit these harmful effects, potentially slowing down or preventing the progression of certain cancers.

The BAP1 protein acts as a powerful tumor suppressor in the body, protecting against cancers of the eye, lung lining, brain, skin, and kidney. Inherited variants that disrupt the protein can increase a person's lifetime risk of developing these cancers by up to 50%, typically occurring around middle age.

Andrew J. Waters et al, Saturation genome editing of BAP1 functionally classifies somatic and germline variants, Nature Genetics (2024). DOI: 10.1038/s41588-024-01799-3

WHO agency says talc is 'probably' cancer-causing

The World Health Organization's cancer agency on Friday classified talc as "probably carcinogenic" for humans, however an outside expert warned against misinterpreting the announcement as a "smoking gun".

The decision was based on "limited evidence" that talc could cause ovarian cancer in humans, "sufficient evidence" it was linked to cancer in rats and "strong mechanistic evidence" that it shows carcinogenic signs in human cells, the WHO's International Agency for Research on Cancer (IARC) said.

Talc is a naturally occurring mineral which is mined in many parts of the world and is often used to make talcum baby powder.

Most people are exposed to talc in the form of baby powder or cosmetics, according to the Lyon-based IARC.

But the most significant exposure to talc occurs when talc is being mined, processed or used to make products, it added.

The agency said there were numerous studies which consistently showed an increase in the rate of ovarian cancer in women who use talc on their genitals.

But it could not rule out that the talc in some studies was contaminated with cancer-causing asbestos.

"A causal role for talc could not be fully established," according the agency's findings published in The Lancet Oncology.

 Leslie T Stayner et al, Carcinogenicity of talc and acrylonitrile, The Lancet Oncology (2024). DOI: 10.1016/S1470-2045(24)00384-X

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True scale of carbon impact from long-distance travel revealed

The reality of the climate impact of long-distance passenger travel has been revealed in new research.

Despite only accounting for less than 3% of all trips by UK residents, journeys of more than 50 miles (one way) are responsible for 70% of all passenger travel-related carbon emissions.

The disparity is even greater when international travel is singled out: International journeys are only 0.4% of total trips, but are responsible for 55% of emissions.

The new research, published recently in the journal Nature Energy, also shows that targeting long-distance travel may be a more effective way of tackling emissions than current efforts focusing on local and commuter journeys.

While the number of long and short distance domestic journeys by car has fallen slightly over the last 25 years, international air travel has increased significantly, driven by an increase in trips for leisure and visiting friends and family.

The scale of the impact of long-distance travel is very large indeed. That just less than 3% of our trips are responsible for around 60% of miles and 70% of emissions shows how important long-distance travel is in the fight to combat climate change. Worryingly, long-distance trips, especially flights, have been growing; however, they offer opportunities too.

Using a new metric they have created, called emission reduction sensitivity, the research team has calculated which types of travel could be changed to maximize a reduction in carbon emissions from passenger travel while affecting as few people or trips as possible.

Part 1

The research found that if all car journeys under eight miles were shifted to walking or cycling, there would be a 9.3% reduction in carbon emissions. However, around 55% of all journeys would need to be shifted to achieve this, as most travel is done locally and in cars.

Calculated by dividing the carbon reduction percentage by the percentage of journeys altered, the emission reduction sensitivity for this change would be just 0.17—the lowest recorded in the study.

By contrast, if all flights of less than 1,000 miles were moved to rail, there would be a 5.6% reduction in emissions but only 0.17% of journeys would be affected—resulting in a sensitivity value of 33.2.

At the top end, theoretically limiting everyone who flies now to one return flight abroad per year would have a value of 158.3, as so few journeys would be affected.

The researchers stress that the potential changes are only suggestions meant to make us realize and reassess the impact of our long-distance travel, rather than concrete policy proposals.

While efforts to move local journeys to more sustainable modes of transport are really positive, by omitting aviation emissions from national statistics—as is the case at the moment in nearly all countries—we are not getting a holistic picture and ignoring a large part of the problem.

A call to rethink our travel's carbon impact

The researchers also hope that their findings can act as a driver for policymakers to look at changes in how effort is assigned when dealing with the impact of travel on the environment.

The research also offers the public an insight into the impact that changing their behavior could have.

The important thing both at the policy and personal level is that we prioritize the relatively fewer longer distance trips—especially flights—in order to realize the largest reductions.

Casting a long shadow: the role of long distance travel in carbon emissions from and decarbonisation of passenger travel, Nature Energy (2024). DOI: 10.1038/s41560-024-01561-3 , www.nature.com/articles/s41560-024-01561-3

Part 2

The evidence is mounting: Humans were responsible for the extinction of large mammals

The debate has raged for decades: Was it humans or climate change that led to the extinction of many species of large mammals, birds, and reptiles that have disappeared from Earth over the past 50,000 years?

By "large," we mean animals that weighed at least 45 kilograms—known as megafauna. At least 161 species of mammals were driven to extinction during this period. This number is based on the remains found so far.

The largest of them were hit the hardest—land-dwelling herbivores weighing over a ton, the megaherbivores. Fifty thousand years ago, there were 57 species of megaherbivores. Today, only 11 remain. These remaining 11 species have also seen drastic declines in their populations, but not to the point of complete extinction.

A research group  now concludes that many of these vanished species were hunted to extinction by humans.

They present this conclusion in a review article invited by and published in the journal Cambridge Prisms: Extinction. A review article synthesizes and analyses existing research within a particular field.

The researchers incorporated several research fields, including studies directly related to the extinction of large animals, such as:

• The timing of species extinctions
• The animals' dietary preferences
• Climate and habitat requirements
• Genetic estimates of past population sizes
• Evidence of human hunting

Additionally, they included a wide range of studies from other fields necessary to understand the phenomenon, such as:

• Climate history over the past 1–3 million years
• Vegetation history over the past 1–3 million years
• Evolution and dynamics of fauna over the past 66 million years
• Archaeological data on human expansion and lifestyle, including dietary preferences

Part 1

The dramatic climate changes during the last interglacial and glacial periods (known as the late Pleistocene, from 130,000 to 11,000 years ago) certainly affected populations and distributions of both large and small animals and plants worldwide. However, significant extinctions were observed only among the large animals, particularly the largest ones.

An important observation is that the previous, equally dramatic ice ages and interglacials over the past couple of million years did not cause a selective loss of megafauna. Especially at the beginning of the glacial periods, the new cold and dry conditions caused large-scale extinctions in some regions, such as trees in Europe. However, there were no selective extinctions of large animals.

The large and very selective loss of megafauna over the last 50,000 years is unique over the past 66 million years. Previous periods of climate change did not lead to large, selective extinctions, which argues against a major role for climate in the megafauna extinctions.
Another significant pattern that argues against a role for climate is that the recent megafauna extinctions hit just as hard in climatically stable areas as in unstable areas.
Archaeologists have found traps designed for very large animals, and isotope analyses of ancient human bones and protein residues from spear points show that they hunted and ate the largest mammals.
Early modern humans were effective hunters of even the largest animal species and clearly had the ability to reduce the populations of large animals. These large animals were and are particularly vulnerable to overexploitation because they have long gestation periods, produce very few offspring at a time, and take many years to reach sexual maturity.
The analysis shows that human hunting of large animals such as mammoths, mastodons, and giant sloths was widespread and consistent across the world.

It also shows that the species went extinct at very different times and at different rates around the world. In some local areas, it happened quite quickly, while in other places it took over 10,000 years. But everywhere, it occurred after modern humans arrived, or in Africa's case, after cultural advancements among humans.
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Species went extinct on all continents except Antarctica and in all types of ecosystems, from tropical forests and savannas to Mediterranean and temperate forests and steppes to arctic ecosystems.
Many of the extinct species could thrive in various types of environments. Therefore, their extinction cannot be explained by climate changes causing the disappearance of a specific ecosystem type, such as the mammoth steppe—which also housed only a few megafauna species.
Most of the species existed under temperate to tropical conditions and should actually have benefited from the warming at the end of the last ice age.
The researchers point out that the loss of megafauna has had profound ecological consequences. Large animals play a central role in ecosystems by influencing vegetation structure (e.g., the balance between dense forests and open areas), seed dispersal, and nutrient cycling. Their disappearance has resulted in significant changes in ecosystem structures and functions.

Jens-Christian Svenning et al, The late-Quaternary megafauna extinctions: Patterns, causes, ecological consequences and implications for ecosystem management in the Anthropocene, Cambridge Prisms: Extinction (2024). DOI: 10.1017/ext.2024.4

The numbers of extinct and surviving species come from the freely accessible database PHYLACINE 1.2.1, which lists all known mammals that have lived in the past 129,000 years, including those that have gone extinct recently or are only found in captivity.

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Incredible New Tech Lets Scientists Watch Fetuses Develop in Real Time

Bacterial glitter: New findings open up possibilities for sustainable color technologies

An international team of researchers  has investigated the mechanism that makes some types of bacteria reflect light without using pigments. The researchers were interested in the genes responsible and discovered important ecological connections. Their findings appear in the Proceedings of the National Academy of Sciences.

The iridescent colors known from peacock feathers or butterfly wings are created by tiny structures that reflect light in a special way. Some bacterial colonies form similar glittering structures.

The scientists sequenced the DNA of 87 structurally colored bacteria and 30 colorless strains and identified genes that are responsible for these fascinating colonies. These findings could lead to the development of environmentally-friendly dyes and materials.

Scientists  discovered that the genes responsible for structural color are mainly found in oceans, freshwater, and special habitats such as intertidal zones and deep-sea areas. In contrast, microbes in host-associated habitats such as the human microbiome displayed very limited structural colour. 

The study results indicate that the colorful bacterial colony structures are not only used to reflect light. Surprisingly, these genes are also found in bacteria that live in deep oceans without sunlight. This could imply that the colors could reflect deeper processes of cell organization with important functions, such as protecting the bacteria from viruses, or efficiently colonizing floating food particles. These findings could inspire new, sustainable technologies based on these natural structures.

Colin J. Ingham et al, Structural color in the bacterial domain: The ecogenomics of a 2-dimensional optical phenotype, Proceedings of the National Academy of Sciences (2024). DOI: 10.1073/pnas.2309757121

Researchers reveal a master controller of development and aging

Researchers have unlocked crucial molecular secrets of aging in cells, potentially paving the way to improve quality of life as people age.

The study, published in Cell Metabolism, decoded the process by which genes regulate how people mature as they grow and age.

By analyzing molecular datasets from both people and mice and then comparing different age groups over time, the researchers investigated the activity of genes involved in both developmental and aging processes.

Master controller genes regulate which genes are turned on or off in each of our cells, making sure that each cell does its specific job.

The scientists followed the activity of the master regulator Activator Protein 1 or AP-1 and found that it progressively activated adult genes, while the activity of 'early-life' genes involved in development were dialed down, and this process was shared across cell types.

The study found this process in our cells was predictable across the different life stages, as people mature.

It was ongoing in adulthood, likely because AP-1 is also activated by a number of stress and inflammatory processes as well as by a protein in our blood that increases with age. This further dampens genes most active early in life, which may drive many of the predictable changes of aging.

To address the diseases associated with aging, like Alzheimer's disease, metabolic liver disorders and stroke, researchers must first understand the process causing bodies to age.

By pinpointing AP-1 as a master controller linked to aging across cell types, scientists can now study the effects of drugs that reduce its activity to extend quality of life. The goal is to prevent diseases of aging from escalating or occurring in the first place by targeting the underlying aging process to allow people to grow older in better health.

 Ralph Patrick et al, The activity of early-life gene regulatory elements is hijacked in aging through pervasive AP-1-linked chromatin opening, Cell Metabolism (2024). DOI: 10.1016/j.cmet.2024.06.006

Boys born with higher natural resistance to HIV, study finds

Baby girls are more likely to acquire HIV from their mothers during pregnancy or childbirth than infant boys, who are conversely more likely to achieve cure or remission, researchers say in a new study that sheds light on the gender differences in immune systems.

An estimated 1.3 million women and girls living with HIV become pregnant each year and the rate of transmission to the child during pregnancy, labor, delivery or breastfeeding—in the absence of any intervention—ranges from 15 to 45%, according to the World Health Organization.

This new study identified some of the key mechanisms by which sustained HIV remission can be achieved—mechanisms that are relevant to children and adults alike.

Researchers  evaluated 284 infants in KwaZulu-Natal, South Africa, one of the world's highest HIV-prevalent areas, who were started at birth on a mix of HIV medicines known as combination anti-retroviral therapy (cART), after being exposed to HIV during pregnancy.

They found that HIV transmission to male fetuses was 50% less common than to females.

Affected males had lower levels of the virus in the blood and to date, in this study, four male infants have been identified who have achieved HIV cure/remission—i.e. maintained undetectable levels of HIV in the blood even without therapy.

HIV cure is categorized as "true cure" in which the virus has been eradicated totally from the body and "functional cure" or "cure/remission," in which the virus is no longer detectable in the blood even after treatment has been discontinued.

The researchers say the disparity found between male and female infants is likely due to the lower levels of activated CD4 T cells in male fetuses than in females, making it harder for the virus to establish a reservoir and providing a barrier against infection.

If by chance a virus gets transmitted to a male, it struggles to persist because there are not enough activated CD4 T cells available to sustain the infection.

CD4 T cells are a type of white blood cell that help the body fight infections such as HIV. They are an important part of the immune system and are targeted by HIV during infection. HIV spreads more slowly with lower CD4 T cell counts.

Nomonde Bengu et al, Sustained aviremia despite anti-retroviral therapy non-adherence in male children after in utero HIV transmission, Nature Medicine (2024). DOI: 10.1038/s41591-024-03105-4

Air pollution linked to a decrease in IVF birth rate success, new study shows

A pioneering study, presented at the ESHRE 40th Annual Meeting in Amsterdam, has revealed that exposure to fine particulate matter (PM) prior to the retrieval of oocytes (eggs) during in vitro fertilization (IVF) can reduce the odds of achieving a live birth by almost 40%.

The study analyzed PM10 exposure in the two weeks leading up to oocyte collection, finding that the odds of a live birth decreased by 38% (OR 0.62, 95% CI 0.43–0.89, p=0.010) when comparing the highest quartile of exposure (18.63 to 35.42 µg/m3) to the lowest quartile (7.08 to 12.92 µg/m3). The study abstract was published in Human Reproduction.

Conducted over an eight-year period in Perth, Australia, the research analyzed 3,659 frozen embryo transfers from 1,836 patients. The median female age was 34.5 years at the time of oocyte retrieval and 36.1 years at the time of frozen embryo transfer.

The study examined air pollutant concentrations over four exposure periods prior to oocyte retrieval (24 hours, two weeks, four weeks, and three months), with models created to account for co-exposures.

Increasing PM_2.5 exposure in the three months prior to oocyte retrieval was also associated with decreased odds of live birth, falling from 0.90 (95% CI 0.70–1.15) in the second quartile to 0.66 (95% CI 0.47–0.92) in the fourth quartile.

Importantly, the negative impact of air pollution was observed despite excellent overall air quality during the study period, with PM₁₀ and PM_2.5 levels exceeding WHO guidelines on just 0.4% and 4.5% of the study days, respectively.

 Leathersich S.J, et al, Particulate matter (PM2.5 and PM10) exposure prior to oocyte collection is associated with decreased live birth rates in subsequent frozen embryo transfers. Human Reproduction (2024).