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Comment by Dr. Krishna Kumari Challa 22 minutes ago

Research identifies lasting brain changes associated with adolescent binge alcohol exposure
In male rats, intermittent ethanol exposure during adolescence caused persistent disruption of astrocyte–synapse coupling in the dorsal hippocampus and heightened fear-related behaviour in adulthood after abstinence. Enhancing astrocyte calcium signalling partially restored gliotransmitter availability and reduced behavioural effects, indicating astrocyte dysfunction as a potential therapeutic target.

O. Coulter et al, Adolescent alcohol exposure disrupts astrocyte-synaptic structural and functional coupling in the male dorsal hippocampus, Molecular Psychiatry (2026). DOI: 10.1038/s41380-026-03817-8

Comment by Dr. Krishna Kumari Challa 27 minutes ago

Nature's colour palette explains why everything we see is a mix of red, yellow, green and blue

Biologists and linguists alike have long puzzled over the universal human tendency to see and name colours as a combination of four "pure" hues—red, yellow, green and blue.
Most people and most cultures do not perceive red as a combination of orange or purple, for example, whereas they naturally perceive orange as a combination of yellow and red. We also perceive some colors as opposites of one another: red is the opposite of green; blue, the opposite of yellow. We would never describe a color as reddish-green or bluish-yellow.

Biologists have tried and failed to reconcile these four primary opposing colors with the three kinds of cone cells in our eyes that detect different wavelengths of light. Similarly, our subjective experience of colour can't be explained by the network of neurons that process vision in the brain. Yet, as painstakingly documented by linguist Paul Kay and the late anthropologist Brent Berlin at UC Berkeley, dozens of human languages, including many unwritten ones, categorize colour based on these four hues, hinting at a unique aspect of human perception.
We tend to think of red as just red, not as a mixture. This same unique property holds for green, blue and yellow: Each appears perceptually pure rather than as a mixture of neighbouring hues.
Neuroscientists have now come up with a theory that explains this conundrum. They demonstrate that the natural world—as distinct from the more colourful human-created world—displays a restricted palette of colours that the human brain, for the sake of simplicity, represents as combinations of only four pure colours. Basically, a combination of just four opposing hues—red versus green and blue versus yellow—provides the simplest way to encode the range of colours found in nature.
The new theory offers "a possible resolution of two historically competing accounts of colour vision that emerged around the same time and were vigorously debated in the late 19th century: Hermann von Helmholtz's theory that colour vision begins with three receptor types versus Ewald Hering's theory of the four unique hues and their opponent nature
We now know that both are valid accounts for how we see colour. The resolution is that while the former speaks to physiological sensory mechanisms in the retina, the latter describes a psychological basis for describing our subjective experience of colour … that is grounded in the structure of the natural visual environment.

Alexander Belsten et al, Emergence of unique hues from sparse coding of color in natural scenes, Journal of the Optical Society of America A (2026). DOI: 10.1364/josaa.598897

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Comment by Dr. Krishna Kumari Challa 1 hour ago

Dozens of genes tied to OCD and tic disorders discovered

An international collaboration has identified 36 genes that substantially raise the risk of obsessive-compulsive disorder (OCD) and chronic tic disorders—providing the most detailed biological understanding of how these conditions develop and might eventually be treated.

Before this study, published in Nature Neuroscience, scientists had found a few genetic clues, each linked separately to OCD or chronic tic disorders.

OCD is characterized by persistent intrusive thoughts and repetitive behaviours, while chronic tic disorders, including Tourette syndrome, involve sudden, repeated movements or vocalizations that are difficult to control. Together, the conditions affect millions worldwide, often beginning in childhood and frequently co-occurring within the same individuals and families.
In the past we knew about a couple of strong genes, so there were few opportunities for the pharmaceutical industry to develop drugs.

Now you've got over 30 targets, and that opens up new possibilities for treatment development.

The study analyzed DNA from nearly 4,000 people diagnosed with OCD, chronic tic disorders such as Tourette syndrome or both conditions. Researchers focused on rare mutations that disrupt genes that help build and operate the brain.

Many of the newly identified genes are shared between OCD and chronic tic disorders. The findings help explain why the conditions often occur together in the same people and families. At the biological level, the disorders appear to involve many of the same brain pathways.

These genes don't act individually. They act in networks. And now you can target whole networks, which will make it easier to design new therapies.
The researchers also found that several of the newly identified genes were previously linked to autism and schizophrenia, reinforcing increasing evidence that multiple psychiatric conditions may stem from related disruptions in brain development and communication.

Brain cells communicate using chemical signals called neurotransmitters that carry messages from one nerve cell to another. The genes identified in the study appear to influence how those signals move through the brain's circuitry.

By revealing the biological systems behind the disorders, the findings could help scientists design drugs that target the underlying mechanisms rather than simply managing symptoms.

Whole-exome sequencing in individuals with obsessive–compulsive disorder and chronic tic disorders identifies 36 large-effect risk genes, Nature Neuroscience (2026). DOI: 10.1038/s41593-026-02419-5

Comment by Dr. Krishna Kumari Challa 1 hour ago

SwRI-led study models new scenarios for Moon formation

Comment by Dr. Krishna Kumari Challa 21 hours ago

Immune cells may have a biological memory that makes weight loss harder after obesity

According to the World Health Organization, one in eight people lives with obesity. Yet despite numerous health education programs, books, articles and treatments, many individuals still struggle to lose weight once they have developed obesity. Why this is so difficult remains a complex puzzle.
However, a new study published in the journal Science Translational Medicine may provide some insights. Researchers discovered that changes in a particular type of immune cell known as adipose tissue macrophages (ATMs) may make weight loss difficult in mice. That's because they carry a biological "memory" of obesity.

Researchers from various institutions studied ATMs in mice. These immune cells regulate fat tissue health by, among other things, safely removing dying cells. The team fed the lab animals a high-fat diet for 12 weeks until they became obese and then switched them to a low-fat diet for a further six weeks.

The scientists noticed that mice that lost the least weight after the dietary switch had less of a protein called CWC22 in the nucleus of their ATM cells. This suggested it may play a role in helping the body shed weight.

To investigate this, the scientists genetically modified a group of mice to lack the Cwc22 gene in a group of immune cells that includes macrophages. CWC22 normally helps cells splice messenger RNA, a process in which RNA is edited before it is used to make proteins.
When these mice were put on a weight-loss diet, they struggled to shed fat. The ATMs could not effectively clear away dead cells, causing more dead cells to build up in fat tissue.

Analysis of these immune cells revealed that a lack of the Cwc22 gene caused a splicing error involving a gene called Scarb1. As a result, the macrophages destroyed their own cleanup receptors before they could reach the cell surface.

Because the macrophages were less able to clear dead cells, they released less inosine. This chemical normally acts as a signal that tells fat cells to break down stored fat. With less inosine available, fat breakdown was impaired.

The research team also discovered that 51.9% of the genes with obesity-induced RNA splicing changes in these immune cells remained altered even after weight loss. This revealed that the immune cells retained a biological memory of obesity, including changes that impaired their normal cleanup duties.

"These findings reveal that aberrant alternative splicing in macrophages underlies resistance to post obesity weight loss," commented the study authors in their paper.
However, it appears one part of this memory can be overridden. When the scientists fixed the Scarb1 splicing error with a synthetic genetic patch, the cleanup receptors were restored, increasing the amount of inosine available and helping the mice lose fat again.

This study suggests that specific alternative splicing events can shape macrophage phenotypes under defined environmental conditions.
This work could help design treatments for people struggling with obesity.

Takuro Miyazaki et al, Aberrant alternative splicing memorized in adipose tissue macrophages impedes efferocytosis during postobesity weight loss, Science Translational Medicine (2026). DOI: 10.1126/scitranslmed.adv0221

Comment by Dr. Krishna Kumari Challa yesterday

High folic acid in pregnancy linked to early bleeding risk
Among 2,400 first-time mothers, folic acid supplementation ≥800 µg/day was associated with increased spotting or mild vaginal bleeding before 16 weeks, particularly in male-bearing pregnancies. Early bleeding was associated with shorter gestation, spontaneous preterm birth, and placental abruption. Folic acid remains essential for neural tube defect prevention.

Hongyan Wang et al, High folic acid supplementation is associated with vaginal bleeding in early pregnancy in a fetal sex-specific manner: findings from two prospective cohort studies, Reproductive Health (2026). DOI: 10.1186/s12978-026-02344-7

Comment by Dr. Krishna Kumari Challa yesterday

Women with type 2 diabetes are more likely than men to develop mental health conditions, study finds
After type 2 diabetes diagnosis, women had higher rates of mental health conditions than men (8.1% vs 5.3%), whereas men had more cardiovascular disease (8.4% vs 5.3%), end-stage renal disease, and hypertension. Mental health comorbidity was associated with premature mortality in both sexes; hypertension was the most frequent subsequent event.

Eto F, et al. Sex differences in trajectories to cardio-renal and mental health outcomes following the onset of type 2 diabetes: An observational cohort study using multi-state analysis in the UK Clinical Practice Research Datalink.PLOS Medicine (2026). DOI: 10.1371/journal.pmed.1005196

Comment by Dr. Krishna Kumari Challa yesterday

Additional transfusion risk emerges for patients with tick-borne alpha-gal syndrome, beyond meat allergy

A new multi-institutional study suggests that alpha-gal syndrome, a tick-borne disease that can result in a chronic allergy to meat and animal byproducts, also may complicate certain patients' ability to safely receive a blood plasma or platelet transfusion.

Alpha-gal syndrome (AGS) is a serious allergy transmitted by a sugar molecule called alpha-gal in the saliva of lone star ticks. First documented in 2025, the allergy is triggered by ingesting meat from mammals, such as beef, pork and lamb, as well as other products from these animals, like dairy and gelatin. An AGS reaction can trigger delayed, severe reactions like hives, stomach pain and anaphylaxis.
At the same time, Dartmouth Health's Dartmouth Hitchcock Medical Center (DHMC) has seen an uptick in recent years in patients with type O blood experiencing severe and even life-threatening allergic reactions after receiving platelets or plasma from type B or AB donors.
Alpha-gal syndrome may increase allergic transfusion reactions in blood group O recipients of B or AB plasma or platelets, particularly in regions with high prevalence. Analysis of >550,000 transfusions supports avoiding B or AB platelet and plasma units for O recipients at risk.
Pathologists hypothesized that these patients may have pre-existing antibodies to alpha-gal from tick bites and that hospitals in regions with higher concentrations of AGS patients, like DHMC, might also see an increase in allergic reactions among O patients receiving B or AB units.
The international team of researchers now reports that transfusion-related alpha-gal syndrome, or TRAGS, is a legitimate manifestation of AGS and should be taken into account in the safety practices of hospital transfusion services.

Richard M. Kaufman et al, Epidemiologic Study of Transfusion-Related Alpha-Gal Syndrome, JAMA Internal Medicine (2026). DOI: 10.1001/jamainternmed.2026.3983

Comment by Dr. Krishna Kumari Challa yesterday

Chemistry behind glow-in-the-dark art

Some of the world's brightest colours don't just reflect light; they create it. Scientists and museum conservators are now uncovering why these luminous pigments fade and how to preserve them for future generations. The findings could help protect artwork while informing the development of longer-lasting phosphorescent materials for a variety of applications, from fashion runways to airport runways.
Most paints and dyes are seen because they bounce visible light back to our eyes. Fluorescent and glow-in-the-dark pigments are different: They absorb light and give it back as a vivid glow. This produces the attention-grabbing visual effects found in pop art, fashion, traffic signage and the glowing stars that many people stick to their bedroom ceilings as children.
Over time, however, these bright materials break down. As the colours become duller, the artwork loses some of the oomph initially intended. For artists, the effect isn't simply cosmetic, because they intentionally use these colours for their visual impact.
Because fluorescent and phosphorescent materials attract attention and improve visibility, they're also important parts of safety signs and markings. By understanding how these materials break down over time, researchers want to help manufacturers develop products that stay brighter longer, such as luminescent paint for airplane runways.
They first identified what the materials are made of. Then, the researchers examined the pigments' photophysics—how they absorb, store and emit light—and how the processes change as the materials age.

The team found that many phosphorescent materials contain inorganic compounds and mineral-based pigments and differ significantly from the organic dyes commonly used in fluorescent colourants.
One of the most surprising initial findings is that prolonged exposure to high levels of humidity can play an equally important—and sometimes greater—role than prolonged exposure to ambient light in breaking down phosphorescent pigments. This information will inform improved storage and exhibition conditions for artworks containing this pigment.
Earlier studies of fluorescent pigments revealed that the compounds responsible for enhancing brightness, called optical brighteners, degrade faster than the pigmentary dyes themselves. As a result, colours appear to darken even when the pigment molecules remain intact.
These results also highlight why conserving modern artworks can be challenging. Conservators restoring fluorescent artworks must match colours under both visible and UV light, while the pigments themselves continue to change over time, making long-term restoration difficult.

Glow in the light & dark: Investigations of the photochemistry of emissive pigments used in art, acs.digitellinc.com/live/37/session/595033

Comment by Dr. Krishna Kumari Challa yesterday

Heart capillaries may build natural bypasses for blood flow after heart attacks

Heart disease caused by blocked arteries is a leading cause of death and illness worldwide. Doctors can restore blood flow with stents or bypass surgery, but these invasive procedures carry risks, including damage caused when blood flow is suddenly restored. But what if a less invasive approach could harness the body's own repair system?

Research shows that some hearts can grow collateral arteries, natural detours that route blood around a blockage. But many heart attack patients lack enough of these backup vessels to survive the injury. Learning how to trigger their growth could save lives, but first doctors need a clear understanding of how the body builds them.

The heart powers a busy highway of arteries and vessels, providing a constant to-and-fro passage for blood. During a heart attack, this passage becomes blocked, usually when a blood clot forms on plaque in a coronary artery and cuts off blood flow to the heart muscle. A study published in Science found that the heart tries to save itself by growing new natural bypass channels to bring blood and oxygen back to damaged tissue.
For a long time, the prevailing theory was that new backup vessels, also known as coronary collateral arteries, grew when cells from existing arteries broke away and assembled into new arteries. The researchers designed genetic tools with fluorescent markers that glow in different colors depending on whether they contact the smooth muscle cells (SMCs) of mature arteries or the bare surface of capillaries, the tiniest blood vessels.

When injected into mice, the tools revealed that capillaries, rather than existing arteries, did most of the heavy lifting in forming new coronary collateral arteries after a heart attack. Capillaries changed their identity and grew into larger, fully mature arteries through a process called capillary arterialization.
The team mapped out the chain reaction inside the cells that drove the transformation of capillary cells into backup vessels. The growth signal VEGF-A activated a protein switch, YY1, which then recruited a methyltransferase protein, SETD1A, to modify the cell's DNA packaging chemically. This activated the gene HES1, which instructed simple capillary cells to reprogram themselves into mature, robust arteries.
The findings challenged a long-standing view and offered a clearer picture of how the heart builds its own backup blood vessels after a heart attack. The researchers identified capillary arterialization as central to the heart's natural effort to restore blood flow, which could be a promising new strategy for helping the heart rebuild its blood supply after injury.

Mingjun Zhang et al, Tracing the origins of de novo coronary collateral formation in cardiac repair, Science (2026). DOI: 10.1126/science.ady3027

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