Measles outbreak leads to dangerous vitamin A toxicity

As a measles outbreak spreads across the U.S., doctors are now seeing a new and unexpected danger: children getting sick from taking too much vitamin A.

At Covenant Children's Hospital in Lubbock, Texas, several unvaccinated children showed signs of liver problems after taking large amounts of vitamin A, according to Dr. Lara Johnson, the hospital's chief medical officer.

U.S. Department of Health and Human Services Secretary Robert F. Kennedy Jr. has promoted vitamin A during the outbreak, even suggesting it might help prevent measles. But doctors say this isn't true.

If people have the mistaken impression that you have an either-or choice of MMR vaccine or vitamin A, you're going to get a lot of kids unnecessarily infected with measles. That's a problem, especially during an epidemic.

And second, you have this unregulated medicine in terms of doses being given and potential toxicities, say the doctors.

The measles, mumps and rubella (MMR) vaccine is the only proven way to prevent measles. It is 97% effective after two doses. 

Vitamin A can be helpful as a supplement for people with measles when given the right dose by a doctor. But taking too much, especially without medical supervision, can be dangerous.

Vitamin A is fat-soluble and can build up in the body. This can lead to dry skin, blurry vision, bone problems and liver damage. In pregnant women, it can even cause birth defects.

If kids are well nourished,  they don't need extra vitamin A.

Recovery for patients with acute toxicity can be rapid when the vitamin is discontinued. Sadly, some of the more serious problems with vitamin A toxicity are not always reversible.

The Council for Responsible Nutrition (CRN), a group representing supplement makers, also warned parents not to give their children high doses of vitamin A.

"While vitamin A plays an important role in supporting overall immune function, research hasn't established its effectiveness in preventing measles infection. CRN is concerned about reports of high-dose vitamin A being used inappropriately, especially in children," it said in a statement.

Doctors say some parents may be following questionable advice from social media or health influencers.

Source: News agencies

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Adverse outcomes increased with long-term inhaled corticosteroids in COPD

For patients with chronic obstructive pulmonary disorder (COPD), long-term inhaled corticosteroid (ICS) treatment is associated with increased rates of adverse composite and specific individual outcomes, according to a study published in the March/April issue of the Annals of Family Medicine.

examined electronic health record data for individuals older than 45 years with COPD to assess long-term ICS risks. The prevalent cohort had a COPD diagnosis any time during the observation period (318,385 individuals), and the inception cohort had a COPD diagnosis after entry into the database (209,062 individuals).

A composite outcome of any new diagnosis of type 2 diabetes, cataracts, pneumonia, osteoporosis, or nontraumatic fracture and recurrent event outcomes of repeated pneumonia or nontraumatic fracture were compared for long- versus short-term ICS exposure (>24 months versus <4 months).

The researchers found that the composite dichotomous outcome was significantly greater for long- versus short-term ICS use for both the prevalent and inception cohorts (hazard ratios, 2.65 and 2.60, respectively). The absolute risk difference of the composite outcome was 20.26% for the inception cohort, with a number needed to harm of five.

For recurrent pneumonia and recurrent fracture, the hazard ratios were significantly increased in the prevalent and inception cohorts (hazard ratios, 2.88 and 2.85 for pneumonia, respectively; 1.77 and 1.57 for fracture, respectively).

"The clinical use of and indications for ICS therapy in COPD should be carefully considered for each individual before initiation of long-term ICS therapy," the authors write.

Wilson D. Pace et al, Adverse Outcomes Associated With Inhaled Corticosteroid Use in Individuals With Chronic Obstructive Pulmonary Disease, The Annals of Family Medicine (2025). DOI: 10.1370/afm.240030

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Short-term reactivation of brain between encoding of memories enhances recall, study finds

Past neuroscience and psychology studies have shown that after the human brain encodes specific events or information, it can periodically reactivate them to facilitate their retention, via a process known as memory consolidation. The reactivation of memories has been specifically studied in the context of sleep or rest, with findings suggesting that during periods of inactivity, the brain reactivates specific memories, allowing people to remember them in the long term.

Researchers  recently conducted a study exploring the possibility that the brain engages in a similar reactivation process during wakefulness to store important information for shorter periods of time. Their findings, published in Nature Neuroscience, suggest that the spontaneous reactivation of specific stimuli in the brain during the brief intervals between their encoding predicts the accuracy with which people remember them at the end of a memory task.

David J. Halpern et al, Study-phase reinstatement predicts subsequent recall, Nature Neuroscience (2025). DOI: 10.1038/s41593-025-01884-8.

New study validates lower limits of human heat tolerance

A new study has confirmed that the limits for human thermoregulation—our ability to maintain a stable body temperature in extreme heat—are lower than previously thought.

The findings are published in the journal Proceedings of the National Academy of Sciences.

The study found that many regions may soon experience heat and humidity levels that exceed the safe limits for human survival

Utilizing a widely used technique known as thermal-step protocols, researchers  exposed 12 volunteers to various heat and humidity conditions to identify the point at which thermoregulation becomes impossible. What made this study different was that participants returned to the laboratory for a daylong exposure to conditions just above their estimated limit for thermoregulation. Participants were subjected to extreme conditions, 42°C with 57% humidity, representing a humidex of approximately 62°C.

The results were clear. The participants' core temperature streamed upwards unabated, and many participants were unable to finish the 9-hour exposure. This data provides the first direct validation of thermal step protocols, which have been used to estimate upper limits for thermoregulation for nearly 50 years.

The implications of this research extend beyond academia. As cities prepare for hotter summers, understanding these limits can help guide health policies and public safety measures.

Robert D. Meade et al, Validating new limits for human thermoregulation, Proceedings of the National Academy of Sciences (2025). DOI: 10.1073/pnas.2421281122

How perceptions are influenced by expectations: Songbird study draws parallels with human speech processing

Past neuroscience and psychology studies have shown that people's expectations of the world can influence their perceptions, either by directing their attention to expected stimuli or by reducing their sensitivity (i.e., perceptual acuity) to variations within the categories of stimuli we expect to be exposed to.

Researchers carried out a study involving songbirds aimed at better understanding how expectation-fueled biases in perception shape brain activity and behaviour.  

Their findings, published in Nature Neuroscience, suggest that the perceptions of songbirds, like those of humans, are influenced by expectations, with peripheral sensory systems utilizing expectations to enhance sensory perception and retain high-fidelity representations of the world.

Human speakers are known to have different voices, while also pronouncing many words differently. Past studies suggest that the human brain possesses robust underlying mechanisms designed to address these differences, by grouping speech sounds into stable perceptual categories, a process referred to as "categorical perception". 

One of these mechanisms is that we use context to cue and bias our perception.

The researchers examined the vocal behaviour and perceptions of songbirds. This is because songbirds are known to share many similarities with humans in terms of their vocal behaviour, thus studying them can help to better understand human speech and speech-related perceptions.

The team's initial experiments utilizing synthesized birdsongs showed that, similarly to humans who are listening to others speak, the perceptions of songbirds while listening to birdsongs are biased by their expectations.

Overall, this study confirmed the hypothesis that the song perceptions of songbirds closely resemble the speech perceptions of humans. Specifically, it gathered strong evidence suggesting that the vocal perceptions of songbirds are also biased and influenced by expectations.

The second important finding of this study emerged from the team's second experiment probing the neural basis of context-dependent categorical perception in songbirds. While their first experiment showed that the birds' expectations influenced how they classified songs, the second was aimed at determining whether the birds' sensory systems reflected this shift in perception.

The findings showed that  the sensory brain appears to use expectation in a more clever way, by rededicating neural responses to focusing on relevant, expected signals, improving perceptual acuity.

"It then leaves the bias to downstream processing like motor and decision-making regions of the brain. In this way, the brain can retain high-fidelity, unbiased, representations of the world, while still incorporating bias to make optimal decisions.

Tim Sainburg et al, Expectation-driven sensory adaptations support enhanced acuity during categorical perception, Nature Neuroscience (2025). DOI: 10.1038/s41593-025-01899-1.

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How Microorganisms looks under the microscope

Implant-derived metals found in cerebrospinal fluid

New research has found that metal particles from artificial joint implants can enter the central nervous system and accumulate in cerebrospinal fluid, raising concerns about potential neurological effects.

Joint replacement surgery has transformed orthopedic care, improving mobility and quality of life for millions of people. Modern implants, made from combinations of metals, are designed for durability and biocompatibility.

Over time, wear and corrosion of these materials can release microscopic particles into surrounding tissue. These byproducts have been linked to problems near the implant  site, including inflammation, tissue damage, and loosening of the joint.

Emerging concerns point to the possibility of metal particles entering the bloodstream and affecting organs far from the implant. Case reports have described serious effects on the heart, thyroid, and nervous system in patients with elevated levels of certain metals, particularly cobalt and chromium. Neurological changes have been reported in some patients following joint replacement.

Previous research has largely focused on these  metals and has relied on blood and serum measurements, leaving open the question of whether such particles reach the central nervous system.

In the study, "Metal Concentrations in Blood and Cerebrospinal Fluid of Patients With Arthroplasty Implants," published in JAMA Network Open, researchers conducted a single-site cross-sectional study to determine whether metals from joint implants can be found in cerebrospinal fluid and bloodstream.

A cohort was assessed of 204 adult participants, 102 with an existing large joint implant (median age 71.7) and 102 in a control group that had never received joint replacement surgery (median age 67.2).

Samples were collected during elective surgery under spinal anesthesia or during lumbar puncture for routine diagnostic or therapeutic reasons. Inductively coupled plasma mass spectrometry measured concentrations of ten metals in blood, serum, and cerebrospinal fluid, including cobalt, chromium, titanium, niobium, zirconium, and others known to be used in implant materials.

Cobalt levels in cerebrospinal fluid were significantly higher in patients with joint implants than in matched controls. Median cobalt concentrations were 0.03 μg/L in the implant group and 0.02 μg/L in the control group. Strong correlations were observed between cobalt levels in cerebrospinal fluid and those in serum and whole blood, suggesting systemic exposure may be reaching the central nervous system.

Part 1

Patients with implants also exhibited higher levels of chromium, titanium, niobium, and zirconium in blood and serum. In cerebrospinal fluid, titanium, niobium, and zirconium levels were significantly elevated, but only when serum levels of these metals were also increased. This is an important finding as it supports the accuracy of less invasive blood sampling as an indicator of possible cerebrospinal fluid inundation.

Patients with implant components containing cobalt-chromium-molybdenum alloys had the highest cerebrospinal fluid concentrations of both cobalt and chromium. Cobalt levels in cerebrospinal fluid were significantly elevated even among patients with implants in place for less than ten years. Pain in the joint containing the implant was also associated with higher cobalt levels in cerebrospinal fluid.

No increase in cerebrospinal fluid metal levels was observed in patients with implants lacking cobalt-chromium-molybdenum components. Patients with cemented implants showed elevated levels of zirconium in blood and serum, though not in cerebrospinal fluid. Aluminum did not appear elevated in the implant group despite being present in certain implant alloys.
Blood-brain barrier integrity, assessed by serum S-100B levels, appeared unaffected and uncompromised in the implant group. Among those with elevated cerebrospinal fluid cobalt or zirconium, serum S-100B levels were lower than in matched controls.

Findings indicate that metal particles released from joint implants can accumulate in the central nervous system, especially those containing cobalt-chromium-molybdenum.
Results suggest that arthroplasty-related metal exposure is not confined to local tissues but extends systemically and may involve the brain. While blood-brain barrier dysfunction was not evident, the presence of these metals in cerebrospinal fluid raises questions about long-term neurological safety.

Anastasia Rakow et al, Metal Concentrations in Blood and Cerebrospinal Fluid of Patients With Arthroplasty Implants, JAMA Network Open (2025). DOI: 10.1001/jamanetworkopen.2025.2281

Part 2

Scientists merge two 'impossible' materials into new artificial structure

An international team of researchers has merged two lab-synthesized materials into a synthetic quantum structure once thought impossible to exist and produced an exotic structure expected to provide insights that could lead to new materials at the core of quantum computing.

The work, described in a cover story in the journal Nano Letters, explains how four years of continuous experimentation led to a novel method to design and build a unique, tiny sandwich composed of distinct atomic layers.

One slice of the microscopic structure is made of dysprosium titanate, an inorganic compound used in nuclear reactors to trap radioactive materials and contain elusive magnetic monopole particles, while the other is composed of pyrochlore iridate, a new magnetic semimetal mainly used in today's experimental research due to its distinctive electronic, topological and magnetic properties.

Individually, both materials are often considered "impossible" materials due to their unique properties that challenge conventional understanding of quantum physics.

The construction of the exotic sandwich structure sets the stage for scientific explorations in what is referred to as the interface, the area where the materials meet, in the atomic scale.

This work provides a new way to design entirely new artificial two-dimensional quantum materials, with the potential to push quantum technologies and provide deeper insight into their fundamental properties in ways that were previously impossible.

Mikhail Kareev et al, Epitaxial Stabilization of a Pyrochlore Interface between Weyl Semimetal and Spin Ice, Nano Letters (2025). DOI: 10.1021/acs.nanolett.4c03969

Air pollution and traffic noise increase the risk of stroke through combination effect

New research shows that air pollution and traffic noise together may pose a greater risk for stroke than either factor alone. The researchers found that even at low levels—below the EU's air quality standards and around WHO noise recommendation levels—the risk of stroke increased significantly.

The study, published in Environment International, analyzed data from 136,897 adults in Sweden, Denmark, and Finland. The results show that a 5 µg/m³ increase in air pollution (PM_2.5) raises the risk of stroke by 9%, while an 11 dB increase in traffic noise increases the risk by 6%.

When both factors are combined, the risk may be even higher. For example, in quieter areas (40 dB), an increase in PM_2.5 was linked to a 6% rise in stroke risk, but in noisier areas (80 dB), the same increase in PM_2.5 raised the risk by 11%, though this result was not statistically significant.

The fact that we see clear associations even at relatively low levels indicates that current exposure limits may not be sufficient to protect public health. Stronger regulations are needed to reduce exposure and lower the risk of stroke and other diseases, say the researchers.

 Huyen Nguyen Thi Khanh et al, Exploring the interaction between ambient air pollution and road traffic noise on stroke incidence in ten Nordic cohorts, Environment International (2025). DOI: 10.1016/j.envint.2025.109403

Developing an Ecotoxicological Classification for Frequently Used Drugs in Primary Care

A classification of drugs based on their environmental impact

Scientists at the University of Lausanne (UNIL) and University center Unisanté classified 35 commonly used drugs based on their impact on the aquatic biodiversity.

The aim of this research is to provide medical staff with a tool for considering the environmental risks associated with certain common drugs when prescribing them. The proposed list is subject to change when new data becomes available, their rarity being a limiting factor for classification.

Every day all around the world, thousands of drugs are consumed, whether to relieve pain, regulate blood pressure or treat infections. But what happens after ingesting these products? Evacuated via urine, many substances end up in wastewater. They are only partially eliminated by these systems, and end up in lakes, rivers and streams, posing a risk to aquatic ecosystems. This risk is now recognized, but it is difficult for doctors to know how to integrate it into their practice.

At the University of Lausanne (UNIL), scientists from the Faculty of Biology and Medicine (FBM) and the Faculty of Geosciences and Environment (FGSE) have carried out a classification of widely-used drugs according to their ecotoxicity, i.e. their danger to the aquatic ecosystem. Published in the International Journal of Environmental Research and Public Health, the study reveals that drugs commonly prescribed in general medicine—to combat inflammation or infection, for example—have significant consequences for the health of fish, algae and bacteria essential to aquatic biodiversity.

The researchers classified 35 drugs commonly consumed into categories ranging from low to high toxicity for aquatic ecosystems. To do this, they cross-referenced three pieces of information: the 50 most widely sold drugs  (by weight), those for which ecotoxicity thresholds exist, and the concentration of those found in the rivers  (in the form of active ingredients).

Among the most problematic drugs are common painkillers and anti-inflammatories such as diclofenac, which is toxic to fish liver and can lead to fish death. There are also antibiotics such as ciprofloxacin, which can eliminate bacteria useful to the ecosystem's balance, and encourage the emergence of antibiotic-resistant bacteria. Mefenamic acid and paracetamol, on the other hand, are in the category with the lowest environmental risks.

This classification is far from complete, because of the lack of data. It does, however, give some initial indications for practitioners, say the eco-toxicologists.

 Developing an Ecotoxicological Classification for Frequently Used Drugs in Primary Care, International Journal of Environmental Research and Public Health (2025). doi.org/10.3390/ijerph22020290

Frustration can lead to failure for search and rescue dogs

Search and rescue dogs are heroes in fur coats, using their incredible sense of smell to find lost hikers, disaster victims, and missing people. But a new study suggests that these life-saving dogs may face an unexpected obstacle: frustration.

Researchers found that frustration significantly impacts search and rescue dogs' ability to perform search tasks effectively. In a study published in Frontiers in Veterinary Science, they reported that when the dogs experience frustration—such as blocked access to a reward or an unfulfilled expectation—they are slower to complete their searches and are more prone to errors.

Search and rescue dogs are trained to work in high-pressure environments, from collapsed buildings to dense forests. While they are known for their endurance and focus, certain factors can affect their work.

To test what factors affect their work, researchers  enlisted a dozen dogs and their handlers to participate in three activities. The dogs wore special collars to track heart rate and heart rate variability—key indicators of exertion and stress. Researchers also recorded the dogs' search accuracy and speed in locating a target odor and surveyed the dogs' handlers on their behaviors.

In the first activity, the dogs rested under normal, quiet conditions for 10 minutes.

In the second "frustration activity," handlers teased the dogs with an unattainable toy, withheld their attention, and then led the dog to complete a search.

In the third exercise, the handlers led the dogs through a moderate workout before completing the search.
The results showed:
After experiencing frustration, search dogs took significantly longer to indicate they found their search targets.
The dogs made more errors after the frustration activity.
Frustration increased the dogs' heart rate and decreased their heart rate variability, indicating a higher level of stress and reduced ability to recover.
Physical exertion caused increased heart rate but did not change heart rate variability, indicating no significant stress response to exercise.

The researchers say the information is valuable for search and rescue (SAR) handlers, many of whom rely on longstanding training methods that use frustration as a tool to build dogs' perseverance. We often think of frustration as a motivator, but these  findings show that it can backfire, slowing dogs down and increasing errors. And that's a serious concern.

It's our responsibility to make their work as stress-free and enjoyable as possible, they conclude.

Sally Dickinson et al, Frustration and its impact on search and rescue canines, Frontiers in Veterinary Science (2025). DOI: 10.3389/fvets.2025.1546412

Border fences are bad for wildlife

International border barriers everywhere are harming wildlife by bisecting their habitats, disrupting their hunting and collecting patterns and preventing them from commingling. In some cases, the borders are causing so much harm that they could cause certain species to go extinct.

That's according to a new study published in the journal Biological Conservation.

The literature review, which analyzed 42 studies on wildlife and borders by scientists across the globe, was part of a special issue on addressing land degradation.

With border barriers, the habitat that animals once moved freely across is divided, fragmenting populations, reducing availability to water, lowering gene flow and even killing animals that try to cross.

Animals don't recognize political boundaries—they are tied to the resources that they need to survive. It's hard seeing animals come up against a new barrier—a huge wall or fence—that stops their ability to get a drink of water or find seasonal foods, especially in desert environments.

The problem has become worse due to a dramatic increase in border barriers in the 21st century. According to a report from the Migration Policy Institute there were just two dozen border walls across the world in 2000; two decades later, that number has tripled. 

The researchers found   three main ways in which physical borders were harming wildlife.

Part 1

The first is habitat fragmentation. Borders can cut animals off from their natural ranges, and that is especially dangerous for animals with a very small travel radius, such as reptiles and some birds. Imagine a lizard who only travels up to a quarter mile from home. Then, imagine a fence going up in the middle of that lizard's already tiny range, restricting its stomping grounds—and potential food supply—even more. And don't forget that border infrastructure like bright lights, non-native landscaping, roads and increased staff will further hamper that lizard's ability to hunt, forage and even reproduce.
The second involves less genetic variation. International borders can disrupt animals' ability to interact and breed with each other. That means that over time, they become less genetically diverse, leading to a decrease in immunity to certain diseases. With time, they may even become inbred and unable to reproduce.
And, finally, there are fewer safety nets. Some endangered species are legally protected in one country but illegally poached in another. Without international cooperation on wildlife conservation, lax hunting laws and enforcement will continue to hurt animals who exist on both sides of a border fence.
There are a few benefits too:
Even in places where animals are threatened by poaching on one side of a border fence, they're shielded from it on the other—guaranteeing they won't go completely extinct. Borders can also shield animals from disease.
Part 2

"So, the question is how do you keep the positives of border fences and toss the negatives?"
Here are four ways the researchers think physical borders can maintain national security while also minimizing harm to wildlife.

Cut down on lights and noise. Many international border areas were dark, quiet and uninhabited before fences and walls were installed. That means the animals who live there haven't grown accustomed to navigating light-flooded, noise-polluted environments full of human activity. Dimming lights and restricting the hours in which noisy construction can take place would go a long way toward supporting wildlife in those areas.

Let animals pass. What if border walls carved out passageways for small animals? What if border security workers opened temporary gaps in the fence a few times every migratory season? Taking these occasional measures would help lessen the disruption some species have experienced with the construction of border walls.
Use different materials. A coiled, sharp material called concertina wire tops many border fences to discourage people from climbing over. One study found that for some species, concertina wire was responsible for one to two deaths per mile per year along about 600 miles of the U.S.-Mexico border, a perilously high mortality rate. Constructing fences with a different type of wire could save thousands of animals' lives every year.

Increase binational cooperation. To ensure a better future for some of the world's most beloved species, government leaders and scientists on both sides of every border barrier should work together to arrive at common security and preservation goals.

Cole Sennett et al, International border fences and walls negatively affect wildlife: A review, Biological Conservation (2024). DOI: 10.1016/j.biocon.2024.110957

Part 3

Omega-6 fatty acid promotes the growth of an aggressive type of breast cancer, study finds

Linoleic acid, an omega-6 fatty acid found in seed oils such as soybean and safflower oil, and animal products including pork and eggs, specifically enhances the growth of the hard-to-treat "triple negative" breast cancer subtype, according to a preclinical study  by  Medicine investigators. The discovery could lead to new dietary and pharmaceutical strategies against breast and other cancers.

In the study, published March 14 in Science, the researchers found that linoleic acid can activate a major growth pathway in tumor cells by binding to a protein called FABP5. Comparing breast cancer subtypes, the team observed that this growth pathway activation occurs in triple-negative tumor cells, where FABP5 is particularly abundant, but not in other hormone-sensitive subtypes. In a mouse model of triple-negative breast cancer, a diet high in linoleic acid enhanced tumor growth.

This discovery helps clarify the relationship between dietary fats and cancer, and sheds light on how to define which patients might benefit the most from specific nutritional recommendations in a personalized manner.

Omega-6 linoleic acid is a diet-derived nutrient that is considered essential in mammals for supporting multiple bodily processes. However, the abundance of this fat in "Western-style" diets has increased significantly since the 1950s, coinciding with the increased usage of seed oils in fried and ultra-processed foods.

This has led to concerns that excessive omega-6 intake might be one of the explanations for rising rates of certain diseases, including breast cancers. But decades of studies have yielded mixed and inconclusive results, and have never uncovered any biological mechanism tying omega-6s to cancers.

In the new study, the researchers sought to resolve this confusion by initially looking at breast cancer, which has been linked to modifiable factors such as obesity. They looked at the ability of omega-6 fatty acids—particularly linoleic acid, the dominant one in the Western diet—to drive an important, nutrient-sensing growth pathway called the mTORC1 pathway.

A key initial finding was that linoleic acid does indeed activate mTORC1 in cell and animal models of breast cancers, but only in triple-negative subtypes. (The term "triple negative" refers to the absence of three receptors, including estrogen receptors, that are often expressed by breast tumor cells and can be targeted with specific treatments.)

The scientists discovered that this subtype-specific effect occurs because the polyunsaturated fatty acid forms a complex with FABP5, which is produced at high levels in triple-negative breast tumors but not in other subtypes, leading to the assembly and activation of mTORC1, a major regulator of cell metabolism and cancer cell growth.

Part 1

Feeding mice that model triple-negative breast cancer a high-linoleic-acid diet increased FABP5 levels, mTORC1 activation and tumor growth. The researchers also found increased levels of FABP5 and linoleic acid in the tumors and blood samples from newly diagnosed triple-negative patients.

The findings show that linoleic acid can have a role in breast cancer, though in a more targeted and defined context than previously appreciated. The study also is thought to be the first to establish a specific mechanism through which this common dietary ingredient influences disease.

Nikos Koundouros et al, Direct sensing of dietary ω-6 linoleic acid through FABP5-mTORC1 signaling, Science (2025). DOI: 10.1126/science.adm9805

Part 2

Scientists create 'fungi tiles' with elephant skin texture to cool buildings

A team of scientists  has developed "fungi tiles" that could one day help to bring the heat down in buildings without consuming energy.

These wall tiles are made from a new biomaterial combining fungi's root network—called mycelium—and organic waste. Earlier research has shown that mycelium-bound composites are more energy efficient than conventional building insulation materials such as expanded vermiculite and lightweight expanded clay aggregate.

Building on this proven insulating property, the  team worked with local ecology and biomimicry design firm bioSEA to add a bumpy, wrinkly texture to the tile, mimicking an elephant's ability to regulate heat from its skin. Elephants do not have sweat glands and rely on these wrinkles and crevices on their skin to regulate heat.

In laboratory experiments, the scientists found that the cooling rate of their elephant skin–inspired mycelium tile was 25% better than a fully flat mycelium tile, and the heating rate was 2% lower. They also found that the elephant skin-inspired tile's cooling effect improved a further 70% in simulated rain conditions, making it suitable for tropical climates.

Mycelium-bound composites are created by growing fungi on organic matter such as sawdust or agricultural waste. As the fungus grows, it binds the organic matter into a solid, porous composite.

For this study, the  scientists used the mycelium of oyster mushroom (Pleurotus ostreatus)—a commonly found fungus—and bamboo shavings collected from a furniture shop.

These two components were mixed with oats and water and packed into a hexagonal mold with an elephant skin–inspired texture designed by bioSEA using computational modeling and algorithms to select the optimal design.

The mycelium tiles were left to grow in the dark for two weeks, then removed from the hexagonal mold and left to grow in the same conditions for another two weeks.

Finally, the tiles were dried in an oven at 48°C for three days. This final step removes any remaining moisture, prohibiting further mycelial growth.

The scientists found that the elephant skin-inspired tile absorbed heat more slowly. When its bumpy textured surface faced the heat source, its temperature increased by 5.01°C per minute, compared to 5.85°C per minute when its flat surface was exposed to heat. As a control, the scientists also heated a flat mycelium tile and found it gained 5.11°C per minute.

The elephant-skin-inspired tile cooled fastest when heated from the flat side, losing 4.26°C per minute. When heated from the textured side, its flat side lost 3.12°C per minute. The fully flat control tile lost 3.56°C per minute.

Based on these findings, the scientists recommended installing the tiles with the flat side adhered to the building façade and the textured surface exposed to external heat for optimal thermal performance.

 Eugene Soh et al, Biodegradable mycelium tiles with elephant skin inspired texture for thermal regulation of buildings, Energy and Buildings (2024). DOI: 10.1016/j.enbuild.2024.115187

Microplastics detected in cat placentas and fetuses during early pregnancy

In a small study of eight cats at early stages of pregnancy, researchers detected 19 different kinds of microplastic particles in fetuses from two cats and in the placentas of three cats.

Humans and other animals worldwide are increasingly exposed to microplastics, which are small particles of plastic contaminants. Studies suggest that microplastics can have a variety of adverse health effects. For instance, research in rodents suggests that fetuses exposed to microplastics during pregnancy may experience impaired development. Microplastics have also been found in human amniotic fluid, further raising concerns about fetal exposure.

To deepen our understanding of this topic, researchers investigated whether microplastics could be found in cat placentas and fetuses during early stages of pregnancy. They evaluated eight pregnant stray cats that had been brought to a veterinary hospital as part of a population-control program in northern Italy.

Using a standard chemical analysis technique known as Raman spectroscopy, the researchers detected microplastics in fetal tissue from two of the cats and in placental tissue from three of the cats. They found a total of 19 different types of microplastics in the tissue samples.

These findings show that even during early stages of pregnancy, microplastics may accumulate in cat placentas. They also suggest that microplastics may be able to cross the placental barrier and accumulate in cat fetuses. However, further research will be needed to determine whether microplastics in cat placentas and fetuses might impact fetal health and development.

In light of their findings and the findings of earlier studies, the researchers call for limits on the general use of plastics and for the development of alternative materials. They also call for policymakers and industrial stakeholders to enact strategies for mitigating plastic pollution that poses risks to humans and animals.

 Detection of microplastics in the feline placenta and fetus, PLOS One (2025). DOI: 10.1371/journal.pone.0320694

Flowerpot snake's DNA repair ability provides insights into human genetic conditions like Down syndrome

The flowerpot snake, one of the world's smallest snakes, has some unusual distinctions. Also known as the Brahminy blind snake, it's the only known snake species with three sets of chromosomes instead of two—and it can reproduce without a mate.

By analyzing the flowerpot snake's unique genome, scientists are uncovering how the tiny reptile repairs its DNA and prevents harmful mutations. The findings, published in the journal Science Advances, provide valuable insights into genetic repair mechanisms that could deepen our understanding of human gene evolution.

This DNA repair and replication activity supports a fascinating mechanism called premeiotic endoreplication, a process through which the snake duplicates its chromosomes before dividing them, sidestepping the need for the typical pairing of chromosomes seen in sexual reproduction. This mechanism allows the snake to produce offspring that are exact genetic clones of itself.

The flowerpot snake's genetic and reproductive quirks may also provide insights into human trisomy conditions, such as Down syndrome.

For example, we know that having multiple sets of chromosomes is rare for animals, yet flowerpot snakes survive just fine with three instead of the normal two humans have.

Using advanced genomic technology, the research team discovered that the flowerpot snake, native to Africa and Asia, has 40 chromosomes, organized into three subgenomes. These subgenomes formed through complex genetic events, including chromosome fusion in ancestral species. The researchers hypothesize that this genetic structure enables the snake to reproduce without needing sperm from a male partner.

One major question the scientists explored was whether this reproductive strategy comes with evolutionary drawbacks. Asexual species typically struggle because they lack genetic shuffling, which helps eliminate harmful mutations over time. However, the flowerpot snake appears to have developed a way to counteract this risk. The researchers think its slow but steady evolutionary pace helps limit the accumulation of harmful mutations.

They also examined how genetic variations across different flowerpot snake populations suggest chromosome exchanges between the subgenomes. These exchanges appear to balance genetic diversity and stability—maintaining enough variation for adaptation while preventing incompatibilities that could disrupt reproduction.

The study also revealed something unexpected—many of the flowerpot snake's immune-related and sexually selected genes, such as those involved in sperm development, have lost their functions.

Yunyun Lv et al, Genomic Insights into Evolution of Parthenogenesis and Triploidy in the Flowerpot Snake, Science Advances (2025). DOI: 10.1126/sciadv.adt6477. www.science.org/doi/10.1126/sciadv.adt6477

 How heavy drinking damages cognition

For the first time, researchers demonstrate in an animal how heavy alcohol use leads to long-term behavioral issues by damaging brain circuits critical for decision-making.

Rats exposed to high amounts of alcohol exhibited poor decision-making during a complex task, even after a months-long withdrawal period. Key areas of their brains had undergone dramatic functional changes compared to healthy rats.

The findings, published in Science Advances, provide a new explanation of alcohol's long-term effects on cognition.

We now have a new model for the unfortunate cognitive changes that humans with alcohol-use disorder show, say the researchers.

We know that humans who are addicted to alcohol can show deficits in learning and decision-making that may contribute to their poor decisions related to alcohol use. We needed an animal model to better understand how chronic alcohol abuse affects the brain. Knowing what is happening in the brain of an animal when they are having these decision-making difficulties will tell us what is happening in humans.

In their experiments, the researchers found that the rats exposed to drinking did very badly when compared to controls.

The team linked the behavioral difficulties to dramatic functional transformations in the dorsomedial striatum, a part of the brain critical for decision-making. The alcohol had damaged neural circuits, causing alcohol-exposed rats to process information less effectively.

One surprise was how long alcohol dependence impairs cognition and neural function, even after withdrawal.

This may give us insight into why relapse rates for people addicted to alcohol are so high. Alcohol-induced neural deficits may contribute to decisions to drink even after going to rehab. We can clearly demonstrate these deficits can be long-lasting.

Chronic Ethanol Exposure Produces Sex-Dependent Impairments in Value Computations in the Striatum, Science Advances (2025). DOI: 10.1126/sciadv.adt0200

The heart remembers: Scientists describe how early-life cardiac injury in parents influences the next generation

Stress during the first years of life can have effects that last into adulthood. Less is known, however, about the possible inheritance of the consequences of early-life stress by the next generation. Now, scientists at the Centro Nacional de Investigaciones Cardiovasculares Carlos III (CNIC) and the University of Bern in Switzerland have discovered that heart injury early in life in one generation of mice triggers changes in cardiac function in their offspring. The study is published in the journal Circulation.

A family history of heart attack is known to influence an individual's risk of cardiovascular disease. Moreover, the risk for offspring is greater if a parent experienced a heart attack earlier in life. Nevertheless, it has remained unclear if heart injury in a parent directly influences the cardiovascular system of the next generation.

A large number of children require heart surgery every year in teh world, so exploring whether the "memory" of early-life cardiac injury can be transmitted to the next generation offers an important opportunity to increase our understanding of cardiovascular disease and to improve the collection of medical histories.

The new study  analyzed if experimentally induced cardiac injury in male mice could produce an inherited effect in the next generation. 

The results  show that the offspring of fathers with early-life cardiac injury had altered heart function. The offspring of injured fathers showed evidence of altered heart development, characterized by transient expansion of the left ventricle during the first weeks after birth. 

This is really surprising  since the only difference between the newborns was that in one group the father had experienced cardiac injury early in life, while in the other group the father was uninjured.

The offspring of injured fathers also showed alterations in their responses to cardiac injury. These changes included improvements in cardiac remodeling (changes in the size, shape, and function of the heart after induced injury) compared with the offspring of uninjured fathers. This superior cardiac remodeling was associated with an increased volume of blood ejected by the heart per minute.

After injury, the heart normally switches its energy source from lipids to glucose, and this results in an accumulation of lipids in the heart tissue. The offspring of injured fathers accumulated fewer lipids in response to induced heart injury and had higher concentrations of circulating lipids in the blood. These observations suggest that the metabolism of mice with this 'family history' recovers better when these mice are themselves subjected to cardiac injury.

The changes observed in the offspring of injured fathers indicate that cardiac surgery in the first weeks after birth leaves a lasting "memory" that can eventually be transmitted to the next generation.

The researchers conclude that the findings open the way to a better understanding of the impact of heart disorders and underline the potential value of including family surgical history when collecting patient medical histories.

Benedetta Coppe et al, Paternal Cardiac Lesion Induces Cardiac Adaptation in Offspring, Circulation (2025). DOI: 10.1161/CIRCULATIONAHA.124.070323

Using everyday products during pregnancy can affect newborns' metabolism, study shows

A newly published study by researchers found that a mother's exposure to phthalates during pregnancy can affect their newborn's metabolism and brain development.

Phthalates are a group of widely used plasticizers commonly found in a variety of cosmetics and personal care products, such as shampoos, soaps, and detergents, as well as plastic food and beverage containers. Previous research showed phthalates can affect hormones and suggested they may be linked to health effects in mothers and babies.

The study  published in Nature Communications this week was the first to explore and find evidence of how a pregnant woman's exposure to phthalates influences their baby's metabolism  at birth.

Main takeaways include:
Prenatal phthalate levels in the mother's blood during pregnancy were associated with lower levels of key neurotransmitter precursors (related to tyrosine and tryptophan metabolism) important for brain development in the newborn's blood soon after birth.
Higher prenatal phthalate levels were also associated with biological changes linked to lower information processing (or attention) and excitability (or arousal) scores in newborns.
These findings suggest that a mother's exposure to phthalates during pregnancy may influence her newborn's metabolism soon after birth. Furthermore, exposure to phthalates while babies are still in the uterus may also have lasting effects on infant brain development.

Part 1

This was the first study to demonstrate that a mother's exposure to phthalates can impact their baby's metabolome and also the first to show that these biological changes can impact newborn development. This is important because there is a common belief that the placenta protects the baby from a lot of harmful substances, but this study supports the fact that phthalates are able to cross through the placenta and actually impact the baby's biology before they are even born and negatively affect their development over time.
Once pregnant women are exposed to phthalates, these chemicals not only enter their body and disrupt maternal metabolism, but these exposures also impact the metabolism and neurobehavioral functioning of newborns.

And researchers found these substances stay with them in the body after they are born, as we did see some indication of a biological disruption occurring among the newborn babies that has a further impact on the neurodevelopment system.

Susan S. Hoffman et al. Impact of prenatal phthalate exposure on newborn metabolome and infant neurodevelopment, Nature Communications (2025). DOI: 10.1038/s41467-025-57273-z. www.nature.com/articles/s41467-025-57273-z

Part 2

Certain sunflower strains can be induced to form seeds without pollination

Biotechnologists have discovered that sunflowers can form viable haploid seeds through parthenogenesis in the absence of pollination. This discovery opens the possibility of a scalable doubled haploid system in sunflowers, a technique that could reduce the time needed to produce fully inbred lines from six years to 10 months.

Some animals, including certain birds, reptiles, fish, and crustaceans like Daphnia, can reproduce without fertilization through a process known as facultative parthenogenesis. In these species, females can produce offspring without male involvement. Charles Darwin first documented unusual reproductive patterns in plants.

In most flowering plants, seed formation depends on a process called double fertilization. This involves one sperm fertilizing the egg and another fertilizing a separate cell that forms the endosperm, a tissue that nourishes the embryo. Without fertilization, viable seeds rarely develop.

Sunflower is one of the world's most important oilseed crops, producing nearly 55 million metric tons globally in 2023. Because sunflower is a hybrid crop, improving its traits requires creating inbred parent lines, which typically takes six years through repeated self-pollination.

In the study, "Haploid facultative parthenogenesis in sunflower sexual reproduction," published in Nature, researchers examined how sunflowers can form haploid seeds without fertilization. The team conducted a combination of genetic, chemical, and environmental experiments to identify the factors that enable parthenogenesis and support a scalable doubled haploid breeding system.

Researchers tested sunflower plants under controlled greenhouse, growth chamber, and field conditions to identify genetic backgrounds capable of producing haploid seeds without fertilization.

Experiments included chemical treatments, manual and hormonal suppression of pollen, and variation in environmental factors such as light intensity and temperature. Flow cytometry and genetic analysis confirmed haploid seed formation. Tissue culture and chromosome doubling techniques were applied to regenerate fertile, doubled haploid plants.

Part 1

Formation of haploid seeds was first noticed during experiments using a chemical phospholipase inhibitor on pollen. Researchers observed small, shriveled seeds and initially attributed them to the chemical's effects. Later trials showed the same seeds forming even in the complete absence of pollen, leading to the discovery of spontaneous parthenogenesis.

Genetic analysis confirmed the seeds were maternally derived and lacked paternal DNA. Parthenogenesis occurred across multiple sunflower lines, with some producing over 100 haploid seeds per flower head. High-intensity light significantly increased haploid yield, while blue or red light alone had no effect.

Maize pollen combined with boron improved haploid formation in certain genetic backgrounds. Germination trials showed a 40% success rate in soil.
Imaging showed that many haploid embryos which formed without fertilization had irregular shapes or multiple axis-like centers. Each seed still contained a single embryo, but some developed multiple shoot-like structures after germination. Tissue culture was used in regenerating healthy seedlings from these atypical forms.

Chromosome doubling produced fertile, seed-setting plants, with some individuals generating up to 188 seeds.

Unlike most flowering plants, sunflower embryos survived and germinated using nutrient reserves stored in the cotyledons, bypassing the usual requirement for endosperm development. This bypass of the endosperm requirement is highly unusual.

Discovery of parthenogenesis in sunflower introduces a previously unrecognized reproductive pathway in a major global crop. Researchers demonstrated that haploid seeds can develop without fertilization and be converted into fully fertile plants, offering a faster route to inbred line development.

Timothy Kelliher, Haploid facultative parthenogenesis in sunflower sexual reproduction, Nature (2025). DOI: 10.1038/s41586-025-08798-2. www.nature.com/articles/s41586-025-08798-2

Marco Todesco et al, Sunflower 'virgin births' enable accelerated crop breeding, Nature (2025). DOI: 10.1038/d41586-025-00904-8

Part 2

Exposure to antibiotics as a newborn can impair immune response to vaccines, study finds

Immunization programs save millions of lives every year by protecting against preventable diseases. The immune response to vaccines, however, varies significantly between individuals, and the results can be suboptimal in populations at a higher risk of developing infectious diseases. Growing evidence suggests that differences in gut microbiota could be a key factor driving these variations.

A recent  study published in Nature found that babies treated with antibiotics within the first few weeks of their life showed weaker immune response to vaccines due to reduced levels of Bifidobacterium—a bacterial species that lives in the human gastrointestinal tract. Replenishing Bifidobacterium in the gut microbiome using probiotic supplements such as Infloran showed promising results in restoring the immune response.

The investigation revealed that children who were directly exposed to neonatal antibiotics, not the ones exposed to maternal antibiotics, produced much lower levels of antibodies against multiple polysaccharides included in the 13-valent pneumococcal conjugate vaccine or PCV13 vaccine.

Part 1

Streptococcus pneumoniae, a bacteria known for causing serious diseases like pneumonia, blood infections, and meningitis, is surrounded by a capsule made up of polysaccharides, or sugar molecules that help the bacteria evade attacks by the body's immune system.

The PCV13 vaccine makes it easier for the immune system to attack S. pneumoniae and produce antibodies by linking the polysaccharide capsule layer to proteins. Exposure to neonatal antibiotics reduces antibody production against such polysaccharides, weakening the immune response.

Experiments on germ-free mice revealed that the lower immune response was linked to a reduced abundance of Bifidobacterium in the gut microbiome. However, giving the mice a mix of Bifidobacterium species or Infloran, a commonly used infant probiotic, helped reverse the negative effects of antibiotics and regain the immune response to PCV13.

The researchers propose that restoring a healthy Bifidobacterium-rich microbiota in antibiotic-exposed infants before their vaccination might enhance the antibody responses to vaccination, leading to better protection against infectious diseases.

David Lynn, Bifidobacteria support optimal infant vaccine responses, Nature (2025). DOI: 10.1038/s41586-025-08796-4. www.nature.com/articles/s41586-025-08796-4

Part 2

Air pollution and extreme heat increase mortality in India

A new study from the Institute of Environmental Medicine, Karolinska Institutet reveals that days with both high air pollution and extreme heat substantially raise the risk of death in Indian cities more than either factor alone. The findings are published in the journal Environment International.

This study included daily counts of death from 10 major Indian cities between 2008 and 2019.

Researchers applied two advanced spatiotemporal models to estimate daily exposure levels of ambient air pollution and temperature. By analyzing approximately 3.6 million deaths, they found that the association between PM2.5 and mortality was particularly strong at high temperatures.

A 10 μg/m³ increase in fine particulate matter (PM2.5) was associated with a 4.6% rise in daily deaths on extremely hot days—substantially higher than the 0.8% increase observed on regular warm days. Similarly, the risk of death rose by 8.3% when temperatures shifted from warm to extremely hot at a pollution level of 20 μg/m³—but surged to 64% when PM2.5 reached 100 μg/m³. These results highlight a concerning synergy between heat and air pollution, showing that their combined effects on health are significantly more harmful than either factor alone.

The study emphasizes the need for integrated strategies to address both air pollution and climate change in India, where global warming is expected to further exacerbate the situation.

Jeroen de Bont et al, Synergistic associations of ambient air pollution and heat on daily mortality in India, Environment International (2025). DOI: 10.1016/j.envint.2025.109426

Research  reveals signs of life in Earth's extremes, boosting search for alien life

New research  focused on identifying signs of life—biosignatures—in extreme environments here on Earth. Researchers investigated whether microbial active motion (e.g., swimming), morphology, and optical properties could serve as biosignatures using in situ video microscopy at a range of extreme field sites, many of which had not been previously explored with this technique.

These environments are considered strong analogs for extraterrestrial settings, such as those found on other planets and moons in our solar system.

The researchers found that at least one of the three biosignatures (motion, morphology, or optical properties) was present in every environmental sample tested, ranging from hot deserts to Arctic ice and alkaline springs.

This supports the idea that even in extreme environments, some fraction of microbes exhibit detectable life-indicating characteristics.

This research also highlights digital holographic microscopy (DHM) as a promising tool for future space missions analyzing liquid samples in search of life. It also emphasizes the ubiquity of microbial swimming as a potential biosignature.

To explore this further, researchers introduced chemical and thermal stimuli to test their effects on microbial motility. The responses varied—some environments showed strong microbial reactions, while others showed little to none.

Despite these differences, a consistent finding across all sites was the presence of microbial biosignatures wherever was explored with DHM.

Carl D. Snyder et al, Extant life detection using label-free video microscopy in analog aquatic environments, PLOS ONE (2025). DOI: 10.1371/journal.pone.0318239

Artificial sweetener shows surprising power to overcome antibiotic resistance

Saccharin, the artificial sweetener used in diet foods like yogurts and sugar-free drinks, can kill multidrug-resistant bacteria—including one of the world's most dangerous pathogens.

In 2019, antimicrobial resistance (AMR) killed 1.27 million people globally, with resistant infections contributing to nearly 5 million deaths.

Drug-resistant bacteria such as Acinetobacter baumannii, which causes life-threatening infections in people with a weakened immune system, and Pseudomonas aeruginosa, linked to chronic lung infections and sepsis, are on the World Health Organization's list of top-priority pathogens.

Researchers now  have identified a novel antimicrobial—saccharin. 

 Saccharin breaks the walls of bacterial pathogens, causing them to distort and eventually burst, killing the bacteria. Crucially, this damage lets antibiotics slip inside, overwhelming their resistance systems.

Saccharin has been part of the human diet for longer than 100 years. While it has been extensively tested for safety in people, little was known about its effect on bacteria—until now with a study appearing in EMBO Molecular Medicine.

The research team found that saccharin both stops bacterial growth and disrupts DNA replication and stops the bacteria from forming biofilms—sticky, protective layers that help them survive antibiotics.

They also created a saccharin-loaded hydrogel wound dressing that, in tests, outperformed market-leading silver-based antimicrobial dressings currently used in hospitals.

Artificial sweeteners are found in many diet and sugar-free foods. Now scientists discovered that the same sweeteners you have with your coffee or in a 'sugar-free' drink could make some of the world's most dangerous bacteria easier to treat.

Rubén de Dios et al, Saccharin disrupts bacterial cell envelope stability and interferes with DNA replication dynamics, EMBO Molecular Medicine (2025). DOI: 10.1038/s44321-025-00219-1

Scientists reveal new toxin that damages the gut

Scientists  have discovered how a diarrhea-causing strain of bacteria uses "molecular scissors" to cut open and destroy gut cells, leading to severe illness and sometimes death.

Published in Gut Microbes, the research reveals for the first time the three-dimensional structure of a toxin secreted by enteropathogenic E. coli (EPEC) bacteria, and shows how the bacteria use the toxin to invade and destroy the epithelial cells that line the gut.

The toxin, which is an enzyme called EspC, destroys the cells by cutting up their internal protein structure.

There are more than five types of E. coli that damage epithelial cells in different ways to cause gut infection.

These include STEC, which was responsible for the recent salad spinach recall and uses Shiga toxin to invade gut cells, and EPEC—the subject of this study—which uses the toxin EspC and is the leading cause of diarrhea in children and babies worldwide.

Currently, infections caused by the many diverse strains of E. coli are typically treated with broad-spectrum antibiotics. However, these drugs kill both harmful and beneficial gut bacteria, and E. coli's rapid adaptation ability means these pathogens are becoming resistant to many antibiotics.

 Akila U. Pilapitiya et al, The crystal structure of the toxin EspC from enteropathogenic Escherichia coli reveals the mechanism that governs host cell entry and cytotoxicity, Gut Microbes (2025). DOI: 10.1080/19490976.2025.2483777

Study exposes huge levels of untargeted antibiotic prescribing

Doctors are prescribing antibiotics for tens of thousands of patients with infections, with little or no consideration of prognosis and the risk of the infection worsening, according to a new study by  epidemiologists.

The study of 15.7 million patient records, published in the Journal of the Royal Society of Medicine  on April 4, '25, implies there could be scope to prescribe far fewer antibiotics. The researchers found the probability of being prescribed antibiotics for a lower respiratory tract or urinary tract infection was unrelated to hospital admission risk.

Conversely, many older people—who may not be able to deal with infections without antibiotics—are not receiving them, with the potential of complications and hospital admissions.

Patients with combinations of diseases were 7% less likely than people without major health problems to receive an antibiotic for upper respiratory infections.
Antibiotics are effective in treating bacterial infections, but they carry the risks of antimicrobial resistance (AMR) and loss of effectiveness when used inappropriately.

That is why AMR to antibiotics has been recognized as one of the biggest threats to global public health.

"Given the threat of resistance, there is a need to better target antibiotics in primary care to patients with higher risks of infection-related complications such as sepsis.

But this study finds that antibiotics for common infections are commonly not prescribed according to complication risk and that suggests there is plenty of scope to do more to reduce antibiotic prescribing.
The study also showed that the probability of being prescribed an antibiotic for lower respiratory infections was even more unrelated to complication risk during the pandemic; however, they were only minor changes for urinary tract infections.
Rather than imposing targets for reducing inappropriate prescribing, we argue that it is far more viable for clinicians to focus on improving risk-based antibiotic prescribing for infections that are less severe and typically self-limiting.Prognosis and harm should explicitly be considered in treatment guidelines, alongside better personalized information for clinicians and patients to support shared decision making, say the researchers.

 Ali Fahmi et al, Antibiotics for Common Infections in Primary Care Before, During and after the COVID-19 Pandemic and Extent of Risk-Based Prescribing: Need for Personalised Guidelines, Journal of the Royal Society of Medicine (2025).

Part 2

One-year-old infants already display compositional abilities, study finds

To understand complex objects, humans are known to mentally transform them and represent them as a combination of simpler elements. This ability, known as compositionality, was so far assumed to require fluency in language, thus emerging in childhood after humans have learned to speak and understand others.

Researchers recently explored the possibility that compositionality is based on simple processes and might therefore already be present in infants. Their paper, published in Communications Psychology, provides evidence that infants as young as 1-year-old already possess basic compositional abilities.

One of the central properties of language is compositionality, which is a long word that simply means the capacity to put words together to understand sentences.

In contrast to older children  and adults, infants cannot yet express their thought processes, thus assessing their abilities in experimental settings typically entails observing their behavior. To evaluate their compositional abilities, Dautriche and her colleague, Emmanuel Chemla, carried out three experiments using a well-established experimental paradigm for research with infants, which involves measuring the time they spend gazing at specific objects.

In their three experiments,  researchers gathered evidence that infants can correctly compose simple noun-verb sentences at approximately 14 months of age, can understand compositional facial expressions (i.e., a negation expressed through a facial expression) at one year of age, and can make basic mental physical transformations when they are 10 months old. Collectively, their findings suggest that compositionality can emerge before humans learn to speak, indicating it could be based on simpler processes than previously anticipated.

 The researchers propose that compositionality is a capacity that humans have before learning language, which brings us a little bit closer to better understanding how our minds work and how language evolved. It could be, for instance, that the minds of other species are also compositional and that language might just have built on this feature of the mind.

 Isabelle Dautriche et al, Evidence for compositional abilities in one-year-old infants, Communications Psychology (2025). DOI: 10.1038/s44271-025-00222-9.

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Cocoa extract fails to prevent age-related vision loss, clinical trial finds

Clinical research reports no significant long-term benefit of cocoa flavanol supplementation in preventing age-related macular degeneration (AMD). The paper is published in the journal JAMA Ophthalmology.

AMD is a progressive retinal disease and the most common cause of severe vision loss in adults over age 50. AMD damages the macula, the central part of the retina responsible for sharp, detailed vision. While peripheral sight is typically preserved, central vision loss can impair reading, driving, facial recognition, and other quality of life tasks. Abnormalities of blood flow in the eye are associated with the occurrence of AMD.

Cocoa flavanols are a group of naturally occurring plant compounds classified as flavonoids, found primarily in the cocoa bean. These bioactive compounds have been studied for their vascular effects, including improved endothelial function and enhanced nitric oxide production, which contribute to vasodilation and circulatory health. Previous trials have shown that moderate intake of cocoa flavanols may lower blood pressure, improve lipid profiles, and reduce markers of inflammation, suggesting a role in mitigating cardiovascular and related vascular conditions.

In the study titled "Cocoa Flavanol Supplementation and Risk of Age-Related Macular Degeneration: An Ancillary Study of the COSMOS Randomized Clinical Trial," researchers conducted a double-blind, placebo-controlled randomized clinical trial to examine whether daily supplementation with cocoa extract prevents the development or progression of AMD.

A cohort of 21,442 U.S. adults (12,666 women aged 65 and older, and 8,776 men aged 60 and older) were recruited, with eligibility criteria requiring discontinuation of non-trial cocoa supplements and multivitamins for the 3.6-year duration of the trial. COSMOS included its own multivitamin supplement as one arm of the trial.

Daily supplementation consisted of 500 mg cocoa flavanols containing 80 mg (−)-epicatechin. Randomization assigned participants to either the cocoa extract or a matching placebo group. AMD outcomes were identified through self-reported diagnoses, verified through medical record confirmation. Compliance biomarkers confirmed a threefold increase in flavanol metabolite levels in the cocoa group.

A total of 344 participants experienced a confirmed AMD event, including 316 incident cases and 28 cases of progression. Incidence was 1.5% in the cocoa extract group and 1.7% in the placebo group.

Part 1

Statistical modeling found a non-significant reduced risk during the first two years of treatment (HR, 0.77; 95% CI, 0.59–1.01), and a non-significant effect beyond two years (HR, 1.06; 95% CI, 0.76–1.50). Similar trends were observed in secondary outcomes.

In subgroup analyses, treatment effect varied by hypertension status, with a significant reduced risk in participants without hypertension (HR, 0.63; 95% CI, 0.44–0.92) and no significant findings among those with hypertension (HR, 1.04; 95% CI, 0.80–1.36).

Researchers concluded that cocoa extract supplementation had no significant overall effect on AMD risk over a median 3.6-year period. Although researchers did not rule out a possible early benefit trend, the findings do not support cocoa flavanol supplementation as a preventive strategy for AMD.

However, the researchers acknowledge that this 's a limited sample study. 

William G. Christen et al, Cocoa Flavanol Supplementation and Risk of Age-Related Macular Degeneration, JAMA Ophthalmology (2025). DOI: 10.1001/jamaophthalmol.2025.0353

Female hormones can stimulate immune cells to make opioids that naturally suppress pain

Scientists have discovered a new mechanism that acts via an immune cell and points toward a different way of treating chronic pain. Female hormones can suppress pain by making immune cells near the spinal cord produce opioids, a new study by researchers  has found. This stops pain signals before they get to the brain.

The discovery could help with developing new treatments for chronic pain. It may also explain why some painkillers work better for women than men and why postmenopausal women experience more pain.

The work reveals an entirely new role for T-regulatory immune cells (T-regs), which are known for their ability to reduce inflammation.

The researchers looked at T-regs in the protective layers that encase the brain and spinal cord in mice. Until now, scientists thought these tissues, called the meninges, only served to protect the central nervous system and eliminate waste. T-regs were only discovered there in recent years.

This new research shows that the immune system actually uses the meninges to communicate with distant neurons that detect sensation on the skin.

Further experiments revealed a relationship between T-regs and female hormones that no one had seen before: Estrogen and progesterone were prompting the cells to churn out painkilling enkephalin.

This work could be particularly helpful for women who have gone through menopause and no longer produce estrogen and progesterone, many of whom experience chronic pain.

 Élora Midavaine et al, Meningeal regulatory T cells inhibit nociception in female mice, Science (2025). DOI: 10.1126/science.adq6531. www.science.org/doi/10.1126/science.adq6531

 The Dangers of Going to Space

Molecular clock analysis shows bacteria used oxygen long before widespread photosynthesis

Microbial organisms dominate life on Earth, but tracing their early history and evolution is difficult because they rarely fossilize. Determining when exactly a particular group of microbes first appeared is especially hard. However, ancient sediments and rocks hold chemical clues of available nutrients that could support the growth of bacteria.

A key turning point was when oxygen accumulated in the atmosphere around 2.3 billion years ago. Scientists have used this oxygen surge and how microbes adapted to it to map out bacterial evolution.

In a study published in Science, researchers have constructed a detailed timeline for bacterial evolution and oxygen adaptation.

Their findings suggest some bacteria could use trace oxygen long before evolving the ability to produce it through photosynthesis.

The researchers focused on how microorganisms responded to the Great Oxygenation Event (GOE) some 2.3 billion years ago. This event, triggered in large part by the development of oxygenic (oxygen-generating) photosynthesis in cyanobacteria and carbon deposition, fundamentally changed Earth's atmosphere from one mostly devoid of oxygen to one where oxygen became relatively abundant, as it is today.

Until now, establishing accurate timescales for how bacteria evolved before, during, and after this pivotal transition has been difficult due to incomplete fossil evidence and the challenge of determining the maximum possible ages for microbial groups—given that the only reliable maximum limit for the vast majority of lineages is the moon-forming impact 4.5 billion years ago, which likely sterilized the planet.

The researchers addressed these gaps by concurrently analyzing geological and genomic records. Their key innovation was to use the GOE itself as a time boundary, assuming that most aerobic (oxygen-using) branches of bacteria are unlikely to be older than this event—unless fossil or genetic signals strongly suggest an earlier origin. Using Bayesian statistics, they created a model that can override this assumption when data supports it.

part1

This approach, however, requires making predictions about which lineages were aerobic in the deep past. The team used probabilistic methods to infer which genes ancient genomes contained, and then machine-learning to predict whether they used oxygen.

To best utilize the fossil record, they leveraged fossils of eukaryotes, whose mitochondria evolved from Alphaproteobacteria, and chloroplasts evolved from cyanobacteria to better estimate how and when aerobic bacteria evolved.

Their results indicate that at least three lineages had aerobic lifestyles before the GOE—the earliest nearly 900 million years before—suggesting that a capacity for using oxygen evolved well before its widespread accumulation in the atmosphere.

Intriguingly, these findings point to the possibility that aerobic metabolism may have occurred long before the evolution of oxygenic photosynthesis.
Evidence suggests that the earliest aerobic transition occurred in an ancestor of photosynthetic cyanobacteria, indicating that the ability to utilize trace amounts of oxygen may have allowed the development of genes central to oxygenic photosynthesis.

The study estimates that the last common ancestor of all modern bacteria lived sometime between 4.4 and 3.9 billion years ago, in the Hadean or earliest Archean era. The ancestors of major bacterial phyla are placed in the Archean and Proterozoic eras (2.5–1.8 billion years ago), while many families date back to 0.6–0.75 billion years ago, overlapping with the era when land plants and animal phyla originated.

Notably, once atmospheric oxygen levels rose during the GOE, aerobic lineages diversified more rapidly than their anaerobic counterparts, indicating that oxygen availability played a substantial role in shaping bacterial evolution.
This combined approach of using genomic data, fossils, and Earth's geochemical history brings new clarity to evolutionary timelines, especially for microbial groups that don't have a fossil record.

A geological timescale for bacterial evolution and oxygen adaption, Science (2025). DOI: 10.1126/science.ADP1853

Part 2

Antibiotic resistance among key bacterial species plateaus over time, study shows

Antibiotic resistance tends to stabilize over time, according to a study published in the open-access journal PLOS Pathogens.

In this study, researchers analyzed drug resistance in more than 3 million bacterial samples collected across 30 countries in Europe from 1998 to 2019. Samples encompassed eight bacteria species important to public health, including Streptococcus pneumoniae, Staphylococcus aureus, Escherichia coli, and Klebsiella pneumoniae.

They found that while antibiotic resistance initially rises in response to antibiotic use, it does not rise indefinitely. Instead, resistance rates reached an equilibrium over the 20-year period in most species.

Antibiotic use contributed to how quickly resistance levels stabilized as well as variability in resistance rates across different countries. But the association between changes in drug resistance and antibiotic use was weak, suggesting that additional, yet unknown, factors are at play.

The study highlights that a continued increase in antibiotic resistance is not inevitable and provides new insights to help researchers monitor drug resistance.

When researchers looked into the dynamics of antibiotic resistance in many important bacterial pathogens all over Europe and in the last few decades, they often found that resistance frequency initially increases and then stabilizes to an intermediate level. The consumption of the antibiotic in the country explained both the speed of initial increase and the level of stabilization.

PLOS Pathogens (2025). DOI: 10.1371/journal.ppat.1012945

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Jumbo phages infect cells with a protective cloaking mechanism, researchers discover

In a growing global trend, bacteria are evolving new ways to maneuver around medical treatments for a variety of infections. The rising antibiotic resistance crisis poses a significant public health threat in hospitals and other settings, with infections resulting in millions of deaths in recent years.

Scientists are now looking to bacteriophages—viruses that infect bacteria—and their potential to treat drug-resistant infections. They have begun to look deeper into an intriguing class of large bacteriophage known as "jumbo phages" that exhibit extraordinary features as possible new agents for bacterial infection treatments.

A study by  researchers has shed new light on the unusual ways that phages have evolved to infect bacteria. Over millions of years, viruses and bacteria have engaged in a back-and-forth arms race. Viruses develop new ways to infect bacteria, while bacteria counter by evolving a resistance mechanism.

In order to fully realize the potential of jumbo phages and their promise as new therapeutics, researchers must decipher the mechanisms they employ to infect bacteria and evade the host's defenses.

A new study published in the journal Cell Host & Microbe describes the first-of-its-kind discovery of a type of membrane-bound sac, or vesicle, used by jumbo phages of the Chimalliviridae family.

The researchers  found that immediately after jumbo phages infect a bacterial cell, they form a structure that shields and hides valuable DNA material. Phages use this genetic material to develop a nucleus inside their bacterial hosts.

The newly discovered compartment, which they named the EPI, or early phage infection vesicle, serves as a type of cloaking device that prevents triggering the bacteria's immune system.

When phages infect a bacterial cell, the EPI vesicle protects the genome of the virus during early stages of infection when it's very vulnerable. Bacteria and viruses are often dismissed as simple organisms but they're actually capable of very sophisticated intracellular warfare and this study is a new example of that.

Because most phages simply inject their DNA directly into the host, effectively announcing their arrival within the cell, the results of Chimalliviridae phage's stealth approach came as a revelation to researchers.  The bacteria don't realize that there's a virus in there, producing things that will eventually take over.

Part 1

Researchers identified curious DNA "dots" within infected cells under a light microscope. Professor Elizabeth Villa's laboratory then used high-end imaging technologies to discover that these dots were tiny vesicles containing viral DNA and molecular machineries outside these vesicles.
They found that these vesicles were actually metabolically active, confirming the purpose of the molecular machines hanging outside the vesicles.
Not only did the researchers show that these vesicles are making RNA, but also they are getting ready to establish infection by synthesizing genes important for nucleus formation.

Emily G. Armbruster et al, Sequential membrane- and protein-bound organelles compartmentalize genomes during phage infection, Cell Host & Microbe (2025). DOI: 10.1016/j.chom.2025.03.005

Part 2

Scientists discover how nanoparticles of toxic metal used in MRI scans infiltrate human tissue

 Researchers studying the health risks posed by gadolinium, a toxic rare earth metal used in MRI scans, have found that oxalic acid, a molecule found in many foods, can generate nanoparticles of the metal in human tissues.

In a new paper published in the journal Magnetic Resonance Imaging, a research team  sought to explain the formation of the nanoparticles, which have been associated with serious health problems in the kidneys and other organs.

The worst disease caused by MRI contrast agents is nephrogenic systemic fibrosis. People have succumbed after just a single dose. The condition can cause a thickening and hardening of the skin, heart and lungs and cause painful contracture of the joints.

Gadolinium-based contrast agents are injected prior to MRI scans to help create sharper images.

The metal is usually tightly bound to other molecules and is excreted from the body, and most people experience no adverse effects. However, previous research has shown that even in those with no symptoms, gadolinium particles have been found in the kidney and the brain and can be detected in the blood and urine years after exposure.

Scientists are left with intertwined puzzles: Why do some people get sick, when most don't, and how do gadolinium particles become pried loose from the other molecules in the contrast agent?

Almost 50% of the patients had been exposed only a single time, which means that there's something that is amplifying the disease signal.

In their study, the research team focused on oxalic acid, which is found in many plant-based foods, including spinach, rhubarb, most nuts and berries and chocolate, because it binds with metal ions. The process helps lead to the formation of kidney stones, which result when oxalate binds with calcium. Meanwhile, oxalic acid also forms in the body when people eat foods or supplements containing vitamin C.

In test tube experiments the researchers found that oxalic acid caused minute amounts of gadolinium to precipitate out of the contrast agent and form nanoparticles, which then infiltrated the cells of various organs.

Some people might form these things, while others do not, and it may be their metabolic milieu. It might be if they were in a high oxalic state or a state where molecules are more prone to linking to the gadolinium, leading to the formation of the nanoparticles. That might be why some individuals have such awful symptoms and this massive disease response, whereas other people are fine.

The finding points to a possible way to mitigate some of the risks associated with MRI scan.

The scientists are getting closer to some recommendations for helping these individuals who are susceptible.

Ian M. Henderson et al, Precipitation of gadolinium from magnetic resonance imaging contrast agents may be the Brass tacks of toxicity, Magnetic Resonance Imaging (2025). DOI: 10.1016/j.mri.2025.110383

Marriage linked to higher dementia risk in older adults, 18-year study finds

This one is going to surprise you.

Researchers found that older adults who were divorced or never married had a lower risk of developing dementia over an 18-year period compared to their married peers. Findings suggest that being unmarried may not increase vulnerability to cognitive decline, contrary to long-held beliefs in public health and aging research.

Marriage is often linked to better health outcomes and longer life, but evidence connecting marital status to dementia risk remains inconsistent. 

Prior research has not consistently addressed how marital status relates to specific causes of dementia or how factors such as sex, depression, or genetic predisposition may influence these associations.

In the study, "Marital status and risk of dementia over 18 years: Surprising findings from the National Alzheimer's Coordinating Center," published in Alzheimer's & Dementia, researchers conducted an 18-year cohort study to understand whether marital status was associated with dementia risk in older adults.

More than 24,000 participants without dementia at baseline were enrolled from over 42 Alzheimer's Disease Research Centers across the United States through the National Alzheimer's Coordinating Center. Annual clinical evaluations were conducted by trained clinicians using standardized protocols to assess cognitive function and determine diagnoses of dementia or mild cognitive impairment.

When looking at specific dementia subtypes, all unmarried participants also showed reduced risk for Alzheimer's disease and Lewy body dementia. In contrast, no consistent associations were observed for vascular dementia or frontotemporal lobar degeneration in fully adjusted models. Divorced and never-married groups were also less likely to progress from mild cognitive impairment to dementia.

Risk patterns appeared slightly stronger among men, younger individuals, and participants referred to clinics by health professionals. Yet stratified analyses showed minimal variation, suggesting that the associations held across a wide range of demographic and clinical subgroups.

Researchers concluded that unmarried individuals, particularly those who were divorced or never married, had a lower risk of developing dementia than those who remained married. These associations persisted even after adjusting for physical and mental health, lifestyle factors, genetics, and differences in clinical referral and evaluation.
Alzheimer's disease and Lewy body dementia were higher in married participants. Risk of progression from mild cognitive impairment to dementia was also higher.
The findings contrast with prior studies linking unmarried status to increased dementia risk and offer new evidence on how relationship status may relate to cognitive outcomes when diagnosis is measured under standardized conditions.

Selin Karakose et al, Marital status and risk of dementia over 18 years: Surprising findings from the National Alzheimer's Coordinating Center, Alzheimer's & Dementia (2025). DOI: 10.1002/alz.70072

Part 2

Urban birds host drug-resistant bacteria

Indian cormorants (Phalacocorax fuscicollis) can spread antimicrobial-resistant bacteria in their droppings. Intrigued by the smell of cormorant droppings, veterinary microbiologist Siddhartha Narayan Joardar and his team analysed some of the bird poo and found a strain of E. coli that produced enzymes that helped it resist certain antibiotics. The birds probably pick up the bacterium by eating fish from ponds contaminated by human wastewater, the team suggests. “Growing evidence shows the presence of antimicrobial-resistant bacteria in common urban birds,” says Joardar, which poses a public health threat if it spills over into humans.

https://www.nature.com/articles/d44151-025-00042-0?utm_source=Live+...

https://www.ijah.in/upload/snippet/707_84.pdf

Obesity severity tied to increased risk across 16 common conditions

New research has found that obesity, particularly severe obesity, is strongly associated with the incidence of 16 common health outcomes. Associations remained consistent across sex and racial groups. Strong associations were observed for obstructive sleep apnea, type 2 diabetes, and metabolic dysfunction-associated steatotic liver disease.

Obesity is a risk factor for adverse health outcomes involving multiple organ systems. Prior studies have analyzed conditions individually, limiting understanding of obesity's total health burden. External validity has also been limited by underrepresentation of individuals with class III obesity and of diverse demographic groups.

In the study, "Associations between Class I, II, or III Obesity and Health Outcomes," published in NEJM Evidence, researchers conducted a longitudinal cohort study to understand how different levels of obesity relate to a wide array of health conditions across a diverse U.S. population.

Participants contributed electronic health records, physical measurements, and survey data. Body mass index (BMI) was calculated at enrollment and used to classify individuals as normal weight, overweight, or obese, with further stratification into obesity classes I, II, and III.

Sixteen pre-identified health conditions were evaluated: hypertension, type 2 diabetes, hyperlipidemia or dyslipidemia, heart failure, atrial fibrillation, atherosclerotic cardiovascular disease, chronic kidney disease, pulmonary embolism, deep vein thrombosis, gout, liver disease linked to metabolic dysfunction, biliary calculus, obstructive sleep apnea, asthma, gastroesophageal reflux disease, and osteoarthritis.

Part 1

Cox proportional hazards models were used to estimate the risk of each condition by obesity class, adjusting for sex, age, race or ethnicity, income, and education. Researchers also calculated population-attributable fractions for each condition by obesity class.

Obesity was present in 42.4% of the study population, including 21.2% with class I obesity, 11.3% with class II, and 9.8% with class III. Compared to those with normal weight, individuals with obesity were more likely to be female, Black, have lower income and education levels, and have higher blood pressure and waist-to-hip ratios.

Prevalence and incidence rates increased progressively with higher obesity classes for all 16 health outcomes. Observed associations with class III obesity were strongest for obstructive sleep apnea (hazard ratio 10.94), type 2 diabetes mellitus (7.74), and metabolic dysfunction–associated liver disease (6.72). Weaker associations were found for asthma (2.14), osteoarthritis (2.06), and atherosclerotic cardiovascular disease (1.96).

Obesity was associated with elevated risk across all subgroups, with consistent patterns by sex and race. Population-attributable fractions showed that obesity explained 51.5% of obstructive sleep apnea cases and 36.3% of metabolic liver disease cases, and 14.0% of all osteoarthritis cases in the study population were estimated to be attributable to obesity.

Increased risk, particularly at higher severity levels, was associated with all 16 health outcomes studied. Risks rose in a stepwise manner across obesity classes, with the highest burden observed among individuals with class III obesity. Findings remained consistent across demographic subgroups and were supported by data from a large, diverse national cohort.

Associations between obesity and several conditions such as sleep apnea, type 2 diabetes, liver disease, and heart failure were strong and statistically robust. Population-attributable fractions indicated that a substantial proportion of these conditions may be preventable through effective obesity management.

Zhiqi Yao et al, Associations between Class I, II, or III Obesity and Health Outcomes, NEJM Evidence (2025). DOI: 10.1056/EVIDoa2400229

Part 2