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Comment by Dr. Krishna Kumari Challa on February 24, 2026 at 10:01am

How your body senses cold—and why menthol feels cool

When you step outside on a winter morning or pop a mint into your mouth, a tiny molecular sensor in your body springs into action, alerting your brain to the sensation of cold. Scientists have now captured the first detailed images of this sensor at work, revealing exactly how it detects both actual cold and the perceived cool of menthol, a compound derived from mint plants.

The study focused on a protein channel called TRPM8 which acts like a microscopic thermometer inside your body. It's the primary sensor that tells your brain when it's cold.

TRPM8 sits in the membranes of sensory neurons innervating the skin, oral cavity, and eyes. It responds to cold temperatures—roughly between 46°F and 82°F—by opening up and allowing ions to flow into the cell, which triggers a nerve signal to the brain. It's also the reason menthol, eucalyptus, and certain other compounds produce that characteristic cooling sensation.

Menthol is like a trick. It attaches to a specific part of the channel and triggers it to open, just like cold temperature would. So even though menthol isn't actually freezing anything, your body gets the same signal as if it were touching ice.

The researchers discovered that cold and menthol activate the channel through shared yet distinct allosteric networks: cold primarily triggers changes in the pore region (the part that actually opens to let ions through), while menthol binds a different part of the protein and induces shape changes that propagate to the pore. When cold is combined with menthol, the response is enhanced synergistically.

The findings have medical implications. When TRPM8 doesn't function properly, it has been linked to conditions including chronic pain, migraines, dry eye and certain cancers.

https://www.biophysics.org/news-room/scientists-show-how-your-body-....

Comment by Dr. Krishna Kumari Challa on February 24, 2026 at 9:53am

2-month-olds see the world in a more complex way than people thought: study

A new study suggests that babies are able to distinguish between the different objects they see around them at 2 months old.

The findings, published this week in Nature Neuroscience, may help doctors and researchers better understand cognitive development in infancy.

It really tells us that infants are interacting with the world in a lot more complex of a way than we might imagine.

The study looked at data from 130 2-month-olds who underwent brain scans while awake. The babies viewed images from a dozen categories commonly seen in the first year of life, such as trees and animals. When babies looked at an image like a cat, their brains might "fire" a certain way that researchers could record. If they looked at an inanimate object, their brains would fire differently.

The technique—known as functional magnetic resonance imaging, or fMRI—allowed scientists to examine visual function more precisely than in the past.

So even at 2 months of age, infants can distinguish between different objects, according to this new study.

Cliona O'Doherty, Infants have rich visual categories in ventrotemporal cortex at 2 months of age, Nature Neuroscience (2026). DOI: 10.1038/s41593-025-02187-8. www.nature.com/articles/s41593-025-02187-8

Comment by Dr. Krishna Kumari Challa on February 24, 2026 at 9:38am

Every time the dogs in the study moved, sensors picked up "puffs" of indoor pollution, with large dogs giving off two to four times more microorganisms than the humans in the same room do. Many of these particles are fluorescent: when exposed to ultraviolet light, they glow ever so slightly, betraying their biological origin.

Shen Yang et al, Our Best Friends: How Dogs Alter Indoor Air Quality, Environmental Science & Technology (2026). DOI: 10.1021/acs.est.5c13324

Part 2

Comment by Dr. Krishna Kumari Challa on February 24, 2026 at 9:28am

Large dogs release two to four times more airborne microbes than humans

Unseen but all around us, the air we breathe in enclosed spaces is crucial to our health and well-being. Indoor air is not simply outdoor air that has been run through a filter: it has its own chemical makeup and a unique combination of particles, gases and microorganisms. Because indoor air has many sources of its own, concentrations of many pollutants can be as high as—or higher than—outdoor levels, especially during everyday activities like cooking or cleaning.
The composition of indoor air, even in well-ventilated spaces, depends on the room's occupants and what they're doing, as well as any objects located there.
In a new study published in Environmental Science & Technology, a team of researchers measured the gases, particles of different sizes and microorganisms that dogs give off, through experiments run under tightly controlled conditions.

Large dogs emit two to four times more airborne microbes than humans, primarily through the release of particles during movement or interaction. Both dogs and humans produce similar amounts of CO2 and ammonia, though dogs have a higher ammonia-to-CO2 ratio, likely due to diet and metabolism. Dogs generate fewer ozone byproducts than humans, and their presence significantly alters indoor air microbiology.

The researchers discovered that the ammonia-to-CO₂ ratio is higher in dogs than in humans. In other words, a dog exhaling the same amount of CO₂ as a human will be producing significantly more ammonia. This difference is probably a function of their more protein-rich food, their unique metabolism and their fast breathing, which is one of the ways they control their body temperature.

When it comes to air pollutants, dogs make their biggest impact through the tiny solid and liquid particles that they send up into the air.

When shaking themselves off, scratching themselves or simply being petted, dogs release sizeable quantities of relatively large particles: dust, pollen, plant debris and microbes.

Part 1

Comment by Dr. Krishna Kumari Challa on February 24, 2026 at 9:21am

Maternal infections during pregnancy increase the risk of suicidal behaviors in their offspring, study finds

Past medical research consistently showed that specific events unfolding during pregnancy can influence the health of their offspring after birth.

Researchers carried out a large-scale study investigating the possible connection between maternal infections during pregnancy and the risk that offspring will exhibit suicidal behaviour later in life. Their findings, published in Molecular Psychiatry, suggest that children who were exposed to an infection while they were still in their mother's womb are at a higher risk of attempting suicide.

Infections caused by an exposure to specific viruses or bacteria activate an immune response known as inflammation. 

Inflammation at crucial stages of brain development has previously been linked to a higher risk of developing some mental health disorders.

As part of their recent study, the researchers analyzed a large amount of data extracted from Denmark's national health registers. The dataset analyzed by them is remarkably large, as it contains information relating to over 2 million individuals. This ultimately allowed the researchers to reliably search for associations between maternal infections and suicidal behaviours, which would be difficult to uncover within smaller datasets.

The researchers analyzed the health records of all individuals above the age of 10 in the period spanning from 1987 to 2021. They specifically looked for maternal and paternal infections, before, during and after they were expecting a child, as well as their children's hospital visits after the age of 10.

Based on their analyses, the researchers estimated that if a mother was exposed to a bacterial or viral infection while she was pregnant, her child had a 46% higher risk of attempting suicide. This percentage appeared to be higher if infections occurred during the second or third trimester. Surprisingly, the risk of offspring attempting suicide was also higher when mothers contracted an infection before or after their pregnancy than if they contracted no infection at all, which could suggest either long-lasting effects of infections or the presence of residual confounding factors.

Interestingly, the researchers found that while maternal infections were linked to a higher risk of suicide attempts in offspring, paternal infections were not. This suggests that the link they observed is unlikely to be a result of social or family-related factors, as it would also hold true for paternal infections, but that it is instead rooted in fetal brain development.

The results of this recent study suggest that women's health before, during and right after pregnancy could be very important for the prevention of mental health-related issues and the reduction of suicide rates.

Massimiliano Orri et al, Association between maternal infections during pregnancy and offspring suicide risk: A national cohort study, Molecular Psychiatry (2026). DOI: 10.1038/s41380-025-03430-1.

Comment by Dr. Krishna Kumari Challa on February 22, 2026 at 10:04am

Closing in on a universal vaccine: Nasal spray protects mice from respiratory viruses, bacteria and allergens
A novel intranasal vaccine in mice provides broad, months-long protection against diverse respiratory viruses, bacteria, and allergens by sustaining both innate and adaptive immune responses in the lungs. This approach bypasses antigen specificity, instead mimicking immune signaling, and could potentially simplify and expand respiratory disease prevention in humans.

Haibo Zhang et al, Mucosal vaccination in mice provides protection from diverse respiratory threats, Science (2026). DOI: 10.1126/science.aea1260. www.science.org/doi/10.1126/science.aea1260

Comment by Dr. Krishna Kumari Challa on February 22, 2026 at 9:55am

Gene variants help explain why food allergies run in families
Comprehensive genetic analysis reveals that nearly 40% of individuals with multiple food allergies carry rare loss-of-function mutations in genes linked to allergy risk, particularly FLG, which affects skin barrier integrity. Advanced sequencing detects more relevant mutations than traditional methods, especially in non-European populations, supporting the value of genetic testing for precise diagnosis and treatment.

Anas M. Khanshour et al, Exome sequencing reveals rare loss-of-function mutations in FLG and immune genes in patients with multiple food allergies, Journal of Allergy and Clinical Immunology (2026). DOI: 10.1016/j.jaci.2026.01.001

Comment by Dr. Krishna Kumari Challa on February 22, 2026 at 9:49am

Birds change altitude to survive epic journeys across deserts and seas
Small migratory birds adjust flight altitude when crossing deserts and seas, flying higher over deserts (2,500–4,000 m) to avoid heat and lower over seas, sometimes below 50 m. Wing morphology and plumage color influence these strategies, with larger wings and darker plumage linked to higher flights. These behaviors have implications for bird conservation and offshore wind farm planning.

Paul Dufour et al, Ecological barrier crossing strategies in small migratory birds depend on wing morphology and plumage color, iScience (2026). DOI: 10.1016/j.isci.2025.114466

Comment by Dr. Krishna Kumari Challa on February 22, 2026 at 8:58am

Why chronic pain lasts longer in women: Immune cells offer clues

Chronic pain lasts longer for women than men, and new research suggests differences in hormone-regulated immune cells, called monocytes, may help explain why.

"The difference in pain between men and women has a biological basis. It's not in your head, and you're not soft. It's in your immune system."

In a new paper in Science Immunology, researchers  found a subset of monocytes release a molecule to switch off pain. These cells are more active in males due to higher levels of sex hormones such as testosterone, the team found.

Females, however, experienced longer-lasting pain and delayed recovery, because their monocytes were less active.

The researchers discovered the same pattern in both mouse models and human patients.

These findings could mean those immune cells can be manipulated into producing more signals to calm pain. While a new treatment is likely decades away, the researchers hope this research could one day help millions of people experience relief with non-opioid treatments—and ensure women's pain is taken seriously.

Monocyte-derived IL-10 drives sex differences in pain duration, Science Immunology (2026). DOI: 10.1126/sciimmunol.adx0292

Comment by Dr. Krishna Kumari Challa on February 22, 2026 at 8:50am

The bouba-kiki effect

When we hear certain sounds, our brains often pair them with specific shapes. For example, most people will associate a sharp-sounding word with a jagged, pointed shape, while a soft, rolling word is linked to something smooth and curved. This fascinating phenomenon is known as the bouba-kiki effect.

The name comes from a classic psychology experiment where people are shown two drawings: one is rounded and bulbous and the other is sharp and spiky. When asked which shape is bouba and which is kiki (both invented words that have no actual meaning), the majority of people choose the round shape for bouba and the spiky one for kiki.

For a long time, scientists have debated whether this is an association we learn as we grow up and begin to speak. However, a recent paper published in the journal Science showed that baby chicks can also spontaneously match these sounds to shapes. It suggests that the ability may be at least partly innate rather than a learned human skill.

Maria Loconsole et al, Matching sounds to shapes: Evidence of the bouba-kiki effect in naïve baby chicks, Science (2026). DOI: 10.1126/science.adq7188

Marcus Perlman et al, In search of meaning, Science (2026). DOI: 10.1126/science.aee8641

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