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Comment by Dr. Krishna Kumari Challa on June 10, 2026 at 11:32am

Cognitive problems
Heat waves can also hamper the ability of animals to learn, as Ridley and her colleagues observed with the southern pied babblers. In one of their experiments, the birds were presented with a simple wooden block with two holes drilled in it, each covered with a lid. If the bird pecked at the lid, it would rotate, revealing either an empty hole or a tasty mealworm. The babblers, Ridley says, "are highly motivated by mealworms."

One lid was dark, and the other a lighter shade of the same color. During heat waves, the birds needed twice as many trials to learn that the mealworm was always hidden under the lid of the same shade.

Another group of scientists tested zebra finches, pretty Australian songbirds, and discovered that if temperatures are high, they too have cognitive problems. When figuring out how to get a mealworm out of a see-through tube with an opening at one end, they would just keep pecking on the tube, says study co-author Elizabeth Derryberry, an evolutionary biologist at the University of Tennessee, Knoxville.

It's the bird equivalent of "banging your head against a brick wall.
Adding to the tally, several years ago researchers showed that when the heat is on, mice have trouble finding their way around a maze and forget objects they've seen the day before. More recently, researchers found that male guppies, popular aquarium fish, also have trouble getting through a maze after spending several days in heat-wave-like 90-degree water, even if the prize for getting it right is a virgin female—which they tend to find particularly attractive.

For animals such as fish and insects that can't control their body temperature, heat waves could be particularly detrimental. "Changes in air temperature will affect brain temperature," says Baird. A hotter brain could hinder the functioning of nerves, and that, she says, "might affect sensing, memory and learning."

When Baird and colleagues tried to teach bumblebees to associate sweet sucrose with the color blue and bitter quinine with yellow, most of the bumblebees learned the trick at 77 degrees, but fewer than half managed to do so at 90 degrees. Such impaired cognition could spell trouble in the field. If the insects forget which flowers they should pollinate—in the case of bumblebees, these include tomatoes and blueberries—or how to get back home with nectar, not only will the pollinators suffer, but human agriculture too, Baird says.

Heat appears to dangerously diminish animal vigilance as well. In Ridley's recent experiments, once the mercury in the Kalahari Desert reached 96 degrees Fahrenheit, pied babblers lost their ability to properly respond to predators. In their studies, researchers lured birds toward a mystery shape covered in a sandy-colored blanket, using worms as bait. Once a babbler approached, the scientists would reveal what was hidden underneath: either a taxidermied catlike carnivore called a genet, or a similarly sized and colored wooden box.
Part 2

Comment by Dr. Krishna Kumari Challa on June 10, 2026 at 11:30am

They call it 'stupid hot' for a reason: Heat muddles animal brains

There is plenty of evidence that animals are affected by heat. Birds, for example, spend less time looking for food and feeding their young; they even sing less. Instead, they'll sit around for hours with wings spread to dissipate the heat, and pant with their beaks wide open. Some animals retreat to shade or hide in cool burrows—again, skipping meals. Bees, meanwhile, splash their faces with droplets of water midflight when the weather is sizzling. This way, "they get convective cooling for their brain.

Some of the first hints that hot temperatures can mess up minds, however, came from studies on humans. Back in the 1800s, Belgian astronomer Adolphe Quetelet noticed that violent crime in France peaked in the summer. Later studies linked high temperatures with gun violence, mental health-related hospital admissions, suicide and gambling. When it's hot, people have trouble making decisions, and their memory suffers. For students at schools without air conditioning, a school year just 1 degree Fahrenheit hotter reduces test scores by 1%, a study found.

Increasingly, there's evidence that other species may also be more aggressive when the mercury shoots up. A 2023 study that combed through nearly 70,000 reports of dogs biting people across eight U.S. cities, from Chicago to Baltimore, found that such incidents were more likely to happen on hot, sunny and smoggy days. The risk was 10% higher on a 90-degree day than on a 60-degree day—and not only because people are more apt to venture out for walks when the sun is shining. The researchers controlled for seasonal effects in their data.
It's likely that both humans and dogs get stressed and more irate at higher temperatures.

Elevated temperatures impair cognitive function and increase aggression in various animal species, affecting learning, memory, decision-making, and social interactions. Heat waves reduce animals' ability to find food, avoid predators, and perform essential behaviours, potentially threatening survival and ecosystem stability. Neurological effects include inflammation, neuron loss, and structural brain changes.

And it's not only dogs: A 2025 study out of China showed that many animals, including snakes and cats, are more inclined to bite people when it gets hot.

Animals also seem to lose their cool with each other, especially if food is involved. Scientists used binoculars and spotting scopes to spy on wild goat-like chamois that feed on protein-rich plants on the slopes of the Italian Apennine Mountains. More than 1,600 hours of observations over two summers revealed that when temperatures rose from 54 degrees Fahrenheit to 64 degrees Fahrenheit, vegetation grew scarcer, and chamois aggression in turn shot up.

The animals became territorial over patches of food. They assumed threatening postures and chased each other—attacks that, at times, escalated. The study authors predict that chamois aggression will go up 50% by 2080 because of climate change.

The small tropical fish called a golden julie also gets confrontational in the heat. Ordinarily, when a golden julie is placed in front of a mirror, it sees its reflected image as a stranger and shows some hostility, raising its fin, for example. But if the normally 78-degree water is raised to a hot 84 degrees, the fish is more likely to get aggressive, and may bite and slap its tail against the mirror as it tries to scare or attack the reflected image.
Part 1

Comment by Dr. Krishna Kumari Challa on June 10, 2026 at 11:04am

To better understand why this happens, the researchers used cryo-electron microscopy, a powerful imaging technique that can visualize proteins at near-atomic resolution.

The team found that TRPM4 contains a flexible drug-binding region that changes shape depending on temperature and calcium levels. Those shape shifts determine which compounds can bind to the protein and what happens when they do.

These structures show exactly how the environment reshapes the binding pocket. Even small changes in temperature or calcium can shift how a drug interacts with the protein.
This work points toward a new concept that Lü and Du call "environment-aware pharmacology." Instead of designing drugs that behave the same way everywhere in the body, scientists could develop therapies that activate only under disease conditions. For example, a drug could activate only inside stressed or damaged cells where calcium reaches abnormally high levels. That could make treatments more precise while reducing adverse side effects.

According to Lü and Du, their study's implications should extend far beyond TRPM4. If temperature and cellular chemistry can dramatically alter one drug target, similar hidden effects may exist across many others.

This work highlights a missing dimension in how we study biology and develop therapeutics.
By bringing physiological conditions back into the picture, we can better understand how proteins function—and how to target them effectively.

Hu, J., et al. Temperature and intrinsic Ca²⁺ reshape TRPM4 pharmacology, Nature Structural & Molecular Biology (2026). www.nature.com/articles/s41594-026-01818-3

Part 2

Comment by Dr. Krishna Kumari Challa on June 10, 2026 at 11:01am

Some drugs 'fail' because of unrealistic testing conditions, scientists discover

A drug once dismissed as ineffective suddenly worked—when scientists tested it under more realistic conditions that mimic the human body. In this surprising new discovery, scientists uncovered a hidden rule of drug behaviour. A medicine's effectiveness can change dramatically depending on the conditions inside our cells.

Drug efficacy can change significantly depending on physiological conditions such as body temperature and intracellular calcium levels, which affect protein structure and drug binding. Testing drugs under more realistic cellular environments revealed previously undetected activities and even opposite effects for some compounds. These findings suggest that drug screening should incorporate physiological variables to improve therapeutic design and predictability.
In the new study, scientists found that two fundamental features of human biology—body temperature and calcium levels inside cells—can change how drugs interact with their targets, sometimes even flipping a drug's effect entirely.

The findings could help explain why some drug candidates look promising in early lab tests but fail later in development. They also could point toward a smarter way to design more effective medicines with fewer unwanted side effects.
Drugs don't act in isolation. They act within the physiological environment of the cell. By incorporating temperature and calcium into their experiments, researchers uncovered drug activities that were completely invisible before.
In early evaluations, researchers commonly test drugs in simplified laboratory conditions—often at room temperature and in artificial chemical environments that do not necessarily reflect the realities inside the human body.
But proteins are dynamic, shape-shifting molecules. Their structure can change in response to their surroundings, including temperature and chemical signals like calcium. Because drugs often work by binding to proteins, even small structural shifts can dramatically change a drug's ability to work. In other words, if the protein changes its shape, the drug's effectiveness can change too.
To better understand this connection, the Northwestern team focused on TRPM4, a protein channel involved in heart rhythm, immune responses and other essential biological functions. They test triphenylphosphine oxide (TPPO), a small synthetic molecule, on cells expressing the TRPM4 channel.

In lab tests under simplified conditions, TPPO appeared inactive, showing no effect on TRPM4. But when the Northwestern team tested it at body temperature (37°C / 98.6°F) and with realistic calcium levels, the supposedly inactive compound powerfully activated the TRPM4 channel.

This completely overturned what they thought they knew. It shows that they may be overlooking important drug candidates simply because they are not testing them under the right conditions.
In another set of experiments, the team uncovered yet another surprise. This time, the researchers tested a compound called Necrocide-1 (NC1), which is known to activate TRPM4. At low calcium levels, NC1 behaved as expected, switching the protein channel on. But when calcium levels increased—as they often do when cells are stressed, injured or diseased—the same molecule largely lost its effect.

Simply put: The cell's internal environment determined whether the drug worked.
This tells us drug behaviour is not fixed. The same molecule can behave very differently depending on the biological context.
part 1

Comment by Dr. Krishna Kumari Challa on June 10, 2026 at 10:31am

'Technostress': Why many older people feel shut out by the digital world
Older adults experience technostress due to rapid digitalization, facing barriers such as inaccessible interfaces, inadequate support, and increased scam risks. While technology can enhance independence and social connection, it also causes distress and exclusion, particularly when digital tools are not age- or culturally-responsive. Digital inclusion requires more than willingness; equitable access, skills, and support are essential to prevent widening disparities.

original article.

Comment by Dr. Krishna Kumari Challa on June 10, 2026 at 10:26am

Asexual reproduction slowed the pace of evolution to a crawl

The way that Earth's first animals reproduced held back life's diversity for millions of years, until stress and competition led to the development of sexual reproduction, which in turn accelerated the pace of evolution.
Researchers from the University of Cambridge studied fossils from the oldest-known animals on Earth, dating from 574 million years ago, and found that asexual reproduction slowed the pace of evolution to a crawl, since it limited competition between different groups.

Their results, reported in the journal Nature Ecology & Evolution, could help explain a longstanding puzzle in paleontology: why animal life appeared on Earth but then barely changed for millions of years, before a second wave of diversification gave evolutionary progress a major boost.

After billions of years of microbial life, during the Ediacaran period, between 635 and 539 million years ago, life exploded in size and the first animals appeared. Some of these earliest animals, such as Fractofusus, could grow as tall as two meters, although most were much smaller.

The influence of reproductive mode on resource competition and diversity patterns in Ediacaran early animal communities, Nature Ecology & Evolution (2026). DOI: 10.1038/s41559-026-03094-2

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Comment by Dr. Krishna Kumari Challa on June 10, 2026 at 10:18am

Dino-killing asteroid may have fueled underground life for 8 million years

The asteroid that caused the extinction of the dinosaurs also created an underground environment suited to supporting new life, and new research suggests it lasted for millions of years longer than previously suspected.

Analysis of feldspar samples from the Chicxulub crater indicates that the impact-generated hydrothermal system persisted for at least 8 million years, significantly longer than previous estimates. This prolonged subsurface environment, sustained by heat, rock permeability, and geothermal conditions, could have supported microbial life and informs understanding of life's origins and potential habitats on other planetary bodies.

The finding has surprised the international team of researchers behind it, who came to their conclusions by pairing sophisticated new analysis of samples taken from the Chicxulub crater in Mexico with computer modeling of the geological effects of the asteroid impact that formed the crater 66 million years ago.
The research, published in the journal Communications Earth & Environment, casts new light on how life may have first been incubated in hydrothermal systems in the earliest chapters of Earth's history and could help direct the search for life on other planets.

Despite the devastation the asteroid's impact caused on the surface, the immense heat brought together fractured rocks and hot water underground, creating a hydrothermal system beneath the crater. The researchers provide evidence that the system persisted for at least 8 million years, around four times longer than previous estimates, making it the longest-lived impact-generated hydrothermal system yet documented.

Annemarie E. Pickersgill et al, A long-lived impact-generated hydrothermal system at the Chicxulub impact structure, Communications Earth & Environment (2026). DOI: 10.1038/s43247-026-03618-5

Comment by Dr. Krishna Kumari Challa on June 9, 2026 at 1:11pm

HIV enters the brain and doesn't leave, drugs intended to reduce brain inflammation increase virus levels
HIV persists in the brain, where standard antiviral drugs have limited efficacy due to poor penetration of the central nervous system. Attempts to reduce brain inflammation by blocking integrins, specifically alpha-4, inadvertently increased viral loads by reducing killer T cell migration while allowing helper T cells to continue introducing HIV. Precision-targeted immune therapies may be necessary to control HIV-associated neurodegeneration without exacerbating viral persistence.

original article.

Comment by Dr. Krishna Kumari Challa on June 9, 2026 at 1:08pm

Hay fever, antihistamines and the evidence on dementia risk

For millions of people around the world, pollen season means weeks of sneezing, itchy eyes, and a blocked or runny nose. The timing varies depending on where you live and which plants are in flower, but grass pollen is one of the most common triggers.
Hay fever, also known as seasonal allergic rhinitis, is an allergic reaction to airborne pollen. Many people manage their symptoms with antihistamines bought from a pharmacy. But recent headlines have raised a worrying question: could some of the medicines used to relieve hay fever symptoms increase the risk of dementia?

Antihistamines block histamine, a chemical released by the immune system during an allergic reaction. Histamine causes symptoms such as itching, sneezing, and a runny nose.

Older, first-generation antihistamines, such as diphenhydramine and chlorphenamine, are more likely to cause drowsiness. Newer, second-generation antihistamines, such as cetirizine, loratadine, and fexofenadine, are generally less sedating.

Some older antihistamines also reduce the activity of acetylcholine, a chemical messenger involved in attention, learning, and memory. Medicines that block the action of acetylcholine are described as having anticholinergic effects.
These older medicines should be used cautiously, particularly in later life. They can cause drowsiness and concentration problems, increasing the risk of falls. People should also take care when driving if a hay-fever medicine makes them sleepy, as highlighted in recent reports.
Some studies have found an association between prolonged use of medicines with strong anticholinergic effects and a higher risk of dementia. These include some treatments for depression, Parkinson's disease, and bladder problems, as well as certain older antihistamines.

There is a plausible reason for concern: acetylcholine plays an important role in memory and thinking. Some medicines used to treat symptoms of Alzheimer's disease work by increasing the amount of acetylcholine available in the brain. Anticholinergic medicines reduce its activity.
One large observational study found that people with the highest exposure to strong anticholinergic medicines had a greater risk of dementia. But observational studies can identify patterns without proving that one factor causes another. People who take these medicines may differ from those who do not in other ways that affect their dementia risk. Some may have underlying health conditions, while others may have been prescribed medication for symptoms linked to the early stages of dementia.

A 2024 study of people with allergic rhinitis also found that dementia risk appeared to increase with higher cumulative doses of antihistamines, meaning the total amount taken over time. The association was stronger for first-generation medicines but was also seen, to a lesser extent, with newer second-generation antihistamines.

That finding was puzzling since second-generation antihistamines are less likely to cross the blood-brain barrier, the protective boundary separating the bloodstream from the brain. They also tend to have fewer anticholinergic effects.
Prolonged use of first-generation antihistamines with strong anticholinergic effects is associated with an increased risk of dementia, while evidence does not support a similar risk for second-generation antihistamines. Confounding factors, such as allergy severity and inflammation, complicate interpretation of these associations. Newer antihistamines are generally preferred due to fewer side effects and lower dementia risk.

original article.

Comment by Dr. Krishna Kumari Challa on June 9, 2026 at 12:06pm

Excessive bite force does not cause alveolar bone loss but significantly worsens it when combined with periodontitis, report researchers in a new study. While traumatic occlusion has long been suspected to exacerbate periodontitis, the molecular mechanisms behind this link were poorly understood. Now, using mouse models of both conditions separately and combined, the researchers conducted comprehensive gene expression analysis across multiple periodontal tissues, identifying key inflammatory pathways upregulated in bone when both conditions were present.
Periodontitis, or inflammation of the tooth-supporting tissues, is one of the most common chronic diseases worldwide and a leading cause of tooth loss in adults. It develops when bacterial buildup around the teeth triggers persistent inflammation, gradually destroying their supporting bone and tissue structures. While bacterial infection is the primary driver of periodontitis, other factors also influence how severely and quickly the condition progresses. These include lifestyle habits such as alcohol consumption and smoking, autoimmune disorders, and—as researchers have long suspected—the way teeth come together when biting or grinding.

When teeth are repeatedly subjected to abnormal or excessive bite forces, known as "traumatic occlusion," supporting structures come under intense mechanical stress. For decades, dentists and scientists have hypothesized that this overload can worsen periodontitis excessively, so that occlusal adjustment (reshaping of the biting surfaces) is already used in clinical practice as a part of gum disease treatment.
Using advanced imaging techniques, including micro-computed tomography, the team measured bone loss around the teeth. They also performed transcriptome analysis to examine the activity of thousands of genes in gum tissue, bone, and the periodontal ligament shortly after disease induction. This enabled them to capture early changes in gene expression associated with each condition. Additionally, they investigated the effects of long-term traumatic occlusion alone over a period of eight weeks.

Interestingly, mice exposed only to traumatic occlusion did not show significant bone loss, even after prolonged exposure. However, when traumatic occlusion was combined with periodontitis, bone loss became significantly more severe.
This confirms that excessive bite force does not directly cause damage but instead amplifies the destructive effects of existing dysregulation caused by periodontitis.

Yosuke Tsuchiya et al, Traumatic Occlusion Exacerbates Bone Resorption by Modifying Gene Expression in the Bone Tissue of Ligature‐Induced Periodontitis in Mice, Journal of Clinical Periodontology (2026). DOI: 10.1111/jcpe.70112

Part 2

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