Comment

Comment by Dr. Krishna Kumari Challa on December 1, 2025 at 8:05am

The research team was also able to demonstrate that mild inflammatory processes in the gut associated with aging further reinforce this mechanism. Inflammatory signals alter iron distribution in the cell and put strain on the metabolism. At the same time, Wnt signaling also weakens—a signaling pathway that is important for keeping stem cells active and functional.

This combination of iron deficiency, inflammation, and Wnt signaling loss acts as an "accelerator" of epigenetic drift. As a result, the aging process in the intestine can begin earlier and spread faster than previously thought.

Despite the complexity of the mechanism, the study also provides encouraging results. The researchers succeeded in slowing down or partially reversing epigenetic drift in organoid cultures—miniature intestinal models grown from intestinal stem cells—by restoring iron import or specifically activating the Wnt signaling pathway. 

Anna Krepelova et al, Iron homeostasis and cell clonality drive cancer-associated intestinal DNA methylation drift in aging, Nature Aging (2025). DOI: 10.1038/s43587-025-01021-x

Part2

Comment by Dr. Krishna Kumari Challa on December 1, 2025 at 8:05am

Why important genes 'go quiet' as we get older

The human gut renews itself faster than any other tissue: every few days, new cells are created from specialized stem cells. However, as we get older, epigenetic changes build up in these stem cells. These are chemical markers on the DNA that act like switches, determining which genes remain active. 

The study, recently published in Nature Aging, was conducted by an international team and it shows that changes in the gut do not occur randomly. Rather, a specific pattern develops over the course of aging, which the researchers refer to as ACCA (Aging- and Colon Cancer-Associated) drift. Researchers observed an epigenetic pattern that becomes increasingly apparent with age.

  Genes that maintain the balance in healthy tissue are particularly affected, including those that control the renewal of the intestinal epithelium via the Wnt signalling pathway.  The changes described as "drifting" can be detected not only in the aging gut, but also in almost all colon cancer samples examined. This suggests that the aging of stem cells creates an environment that promotes the development of cancer. 

The fact that the drift is not evenly distributed throughout the intestine is particularly noteworthy. Each intestinal crypt—a small, tubular section of the intestinal mucosa—originates from a single stem cell. When this stem cell undergoes epigenetic changes, the entire crypt takes on these changes.   Over time, more and more areas with an older epigenetic profile develop in the tissue. Through the natural process of crypt division, these regions continuously enlarge and can continue to grow over many years. 

This explains why the intestines of older people contain a veritable patchwork of crypts that have remained young and others that have aged significantly, and why certain regions are particularly susceptible to producing more degenerated cells, which promotes cancer growth. 

But why does this drift occur? Researchers have shown that older intestinal cells absorb less iron but release more iron at the same time. This reduces the amount of available iron (II) in the cell nucleus, which serves as a cofactor for the TET (ten-eleven translocation) enzymes. These enzymes normally protect from the excess DNA methylations, but if the cell doesn't have enough iron, they can't do their job properly. Excess DNA methylations are no longer broken down.

When there's not enough iron in the cells, faulty markings remain on the DNA. And the cells lose their ability to remove these markings. This has a kind of domino effect: as the TET activity decreases, more and more DNA methylations accumulate, and important genes are switched off; they "fall silent." This can further accelerate epigenetic drift.

Part1

Comment by Dr. Krishna Kumari Challa on December 1, 2025 at 8:04am

Phototherapy could reverse antibiotic resistance

Antimicrobial resistance is a growing global problem, linked to 4.7 million deaths in 2021, a figure that's set to nearly double by 2050. A large proportion of infections are caused by "Gram-negative" bacteria like E. coli which have tough cell walls that block the entry of drugs, meaning fewer treatment options are available. 

Many new antibiotics are improved versions of previous drugs, attacking bacteria in a similar way. But making different antibiotics from scratch is challenging and time-consuming. It's clear we need new strategies, and researchers think innovative chemistry could hold the answer. 

In their study published in the Journal of the American Chemical Society, they focused on an enzyme only found in drug-resistant bacteria, NDM-1, which breaks down commonly used 'beta-lactam' antibiotics like penicillin. 

They  designed a chemical tool, 'Ru1,' composed of a light-activated ruthenium metal complex attached to an organic molecule, or 'ligand,' that binds to NDM-1.

The metal complex is exposed to blue light, causing it to produce molecules called reactive oxygen species that cause damage to NDM-1. 

Through a series of experiments in purified proteins, the team showed that Ru1 damages NDM1's active site, blocking its ability to destroy antibiotics—and it does so a hundred times better in the light. As soon as the light is switched off, Ru1 can no longer cause damage and can be used again. 

The next step was to test if Ru1 works in live E. coli. Although Ru1 did partially inactivate NDM-1 in the live bacteria in the dark, it was thirty times more effective in the light, showing their targeted approach works .

Finally, the researchers showed that Ru1 can effectively sensitize E. coli to an antibiotic called meropenem.  At the maximum concentration tested, Ru1 increased the activity of meropenem by 53 times. Importantly, it didn't show any toxicity to human cells.

  Lars Stevens-Cullinane et al, Light-Activated Metal-Dependent Protein Degradation: A Heterobifunctional Ruthenium(II) Photosensitizer Targeting New Delhi Metallo-β-lactamase 1, Journal of the American Chemical Society (2025). DOI: 10.1021/jacs.5c12405

Comment by Dr. Krishna Kumari Challa on December 1, 2025 at 8:03am

"If stool sticks around too long in the gut, microbes use up all of the available dietary fiber, which they ferment into beneficial short-chain fatty acids," says Johannes Johnson-Martinez, a bioengineer at ISB.

"After that, the ecosystem switches to fermentation of proteins, which produces several toxins that can make their way into the bloodstream."

Sure enough, some of these byproducts were found in these patients' blood samples. Particularly enriched was a metabolite called indoxyl-sulfate, a known product of protein fermentation that can damage the kidneys.

The team suggests the finding is potential evidence of a causal link between bowel movement frequency and overall health.

There is some hope that people can change their habits and, as a result, their health. Recent research suggests your gut microbiome can shift a lot faster than you might think.

For instance, a 2025 study from Germany, yet to undergo peer review, tracked inactive adults who began resistance training twice or three times a week. Those who gained the most strength showed changes in the makeup of their gut bacteria in just eight weeks.

These kinds of changes might help some people move out of the constipation or diarrhea categories and into a healthier bowel-movement range.

Those in the Goldilocks zone of pooping reported eating more fiber, drinking more water, and exercising more often. Their stool samples also showed high levels of bacteria associated with fermenting fiber.

A clinical trial published in 2025 by US researchers found that people with a lot of methane-producing microbes in their guts are especially efficient at turning dietary fiber into short-chain fatty acids.

This suggests that both the amount of fiber and the specific mix of microbes in an individual's gut are important, which explains why two people eating the same diet can experience different health outcomes.

Of course, everybody's found themselves at one extreme or the other at some point in their lives, after catching a stomach bug or eating too much cheese. But this study was looking at people's everyday routine, and reveals how our own version of 'normal' could hint at health issues we weren't aware of.

The research was published in the journal Cell Reports Medicine.

Part2

Comment by Dr. Krishna Kumari Challa on December 1, 2025 at 8:02am

Your daily poop count is important

"How often do you poop?" might sound like a very personal question, but your answer could reveal quite a lot about your overall health.

A study published in July 2024 investigated how often 1,425 people went number two, and compared those stats to their demographic, genetic, and health data.

The healthiest participants reported pooping once or twice a day – a 'Goldilocks zone' of bowel movement frequency.

Pooping too often or too rarely were both associated with different underlying health issues, the team led by researchers at the Institute for Systems Biology (ISB) found.
This study shows how bowel movement frequency can influence all body systems, and how aberrant bowel movement frequency may be an important risk factor in the development of chronic diseases .
"These insights could inform strategies for managing bowel movement frequency, even in healthy populations, to optimize health and wellness

The team looked for possible associations between bowel movement frequency and these health markers, as well as other factors like their age and sex.

In general, those who reported less frequent bowel movements tended to be women, younger, and with a lower body mass index (BMI). But even accounting for these factors, people with constipation or diarrhea showed clear links to underlying health issues.

Bacteria usually found in the upper gastrointestinal tract were more common in stool samples from participants with diarrhea. Their blood samples, meanwhile, showed biomarkers associated with liver damage.

Stool samples from people with less frequent bowel movements had higher levels of bacteria associated with protein fermentation. This is a known hazard from constipation.

Part1

Comment by Dr. Krishna Kumari Challa on December 1, 2025 at 7:58am

This Protein Reawakens Aging Brain Cells in Mice, Study Shows

A discovery by researchers from the Baylor College of Medicine in the US could lead to treatments that clear the troublesome aggregations of protein thought to play a key role in Alzheimer's disease.

Using mice bred to have a condition similar to the neurodegenerative disorder, the team found that elevated levels of a protein called Sox9  triggered specialized brain cells to go into clean-up overdrive, 'vacuuming' up plaques with increased efficiency.

In behavioral and memory tests, the treated mice also performed better, suggesting that the intervention can help protect the brain and reverse cognitive decline – a process that typically occurs in  Alzheimer's   disease as neurons are damaged and destroyed.

https://www.nature.com/articles/s41593-025-02115-w

Comment by Dr. Krishna Kumari Challa on November 30, 2025 at 10:45am

Microplastics pose human health risk in more ways than one

Microplastics in aquatic environments are colonized by pathogenic and antimicrobial-resistant bacteria, with polystyrene and nurdles posing higher risks due to their capacity to adsorb antibiotics and promote biofilm formation. Over 100 unique antimicrobial resistance gene (ARG) sequences were identified on microplastics, exceeding those on natural or inert substrates. These findings highlight microplastics as vectors for the spread of pathogens and ARGs, raising concerns for environmental and human health.

Emily M. Stevenson et al, Sewers to Seas: exploring pathogens and antimicrobial resistance on microplastics from hospital wastewater to marine environments, Environment International (2025). DOI: 10.1016/j.envint.2025.109944

Comment by Dr. Krishna Kumari Challa on November 30, 2025 at 10:42am

When the system evolved under this new combined motion, the changes were immediate and dramatic. The researchers measured the LGI violation and found it had smashed the TTB limit, confirming a new level of quantum weirdness.

Beyond this extreme behavior, they discovered that the strength of the LGI violation increased consistently with how much they mixed the two motions.

"This enhanced nonmacrorealism, as quantified by the violation of LGI beyond the TTB, increases with increasing superposition between the unitaries," the researchers noted in their paper.

What's more, the superposed motion protects against the environmental noises that usually disrupt fragile quantum states. Our superposed unitaries provide robustness against such environmental noise by remarkably increasing the time to which LGI violation persists."

This environmental noise, or decoherence, is one of the biggest obstacles in building quantum computers. By overcoming it, this research could help form a blueprint for more stable quantum computers and technologies.

Arijit Chatterjee et al, Extreme Violations of Leggett-Garg Inequalities for a System Evolving under Superposition of Unitaries, Physical Review Letters (2025). DOI: 10.1103/vydp-9qqq. On arXiv: DOI: 10.48550/arxiv.2411.02301

Part 2

Comment by Dr. Krishna Kumari Challa on November 30, 2025 at 10:42am

Quantum world is even stranger than previously thought, new research confirms

The quantum world is famously weird—a single particle can be in two places at once, its properties are undefined until they are measured, and the very act of measuring a quantum system changes everything. But according to new research published in Physical Review Letters, the quantum world is even stranger than previously thought. 

What happens at the quantum level is in stark contrast to the classical world (what we see every day), where objects have definite properties whether or not we look at them, and observing them doesn't change their nature. To see whether any system is behaving classically, scientists use a mathematical test called the Leggett-Garg inequality (LGI). Classical systems always obey the LGI limit while quantum systems violate it, proving they are non-classical. 

But even in quantum systems, this violation has a limit called the temporal Tsirelson's bound (TTB). In this research, scientists wanted to see if they could break the TTB limit and find even more extreme forms of quantum weirdness. 

They  theorized that a new kind of quantum motion, in which a particle follows two distinct sets of movement instructions simultaneously, could be powerful enough to break the TTB limit. They called this superposition of unitaries.

The team tested their idea in an NMR (nuclear magnetic resonance) machine, which let them control a qubit (the basic building block of quantum information). In this experiment, the qubit was a carbon nucleus within a molecule. The researchers designed a precise quantum circuit using a helper particle (an ancillary qubit) to make the qubit follow two sets of instructions at the same time. Specifically, they combined two different kinds of magnetic rotation on the qubit. 

Part 1

Comment by Dr. Krishna Kumari Challa on November 30, 2025 at 10:40am

Scientists think they have 'detected' dark matter

In the early 1930s, Swiss astronomer Fritz Zwicky observed galaxies in space moving faster than their mass should allow, prompting him to infer the presence of some invisible scaffolding—dark matter—holding the galaxies together. Nearly 100 years later, NASA's Fermi Gamma-ray Space Telescope may have provided direct evidence of dark matter, allowing the invisible matter to be "seen" for the very first time.

Dark matter has remained largely a mystery since it was proposed so many years ago. Up to this point, scientists have only been able to indirectly observe dark matter through its effects on observable matter, such as its ability to generate enough gravitational force to hold galaxies together.

The reason dark matter can't be observed directly is that the particles that make up dark matter don't interact with electromagnetic force—meaning dark matter doesn't absorb, reflect or emit light.

Theories abound, but many researchers hypothesize that dark matter is made up of something called weakly interacting massive particles, or WIMPs, which are heavier than protons but interact very little with other matter. Despite this lack of interaction, when two WIMPs collide, it is predicted that the two particles will annihilate one another and release other particles, including gamma ray photons.

Researchers have targeted regions where dark matter is concentrated, such as the center of the Milky Way, through astronomical observations for years in search of these specific gamma rays.

Using the latest data from the Fermi Gamma-ray Space Telescope, astronomers think they finally detected the specific gamma rays predicted by the annihilation of theoretical dark matter particles. 

They  detected gamma rays with a photon energy of 20 gigaelectronvolts (or 20 billion electronvolts, an extremely large amount of energy) extending in a halolike structure toward the center of the Milky Way galaxy. The gamma-ray emission component closely matches the shape expected from the dark matter halo.

The observed energy spectrum, or range of gamma-ray emission intensities, matches the emission predicted from the annihilation of hypothetical WIMPs, with a mass approximately 500 times that of a proton. The frequency of WIMP annihilation estimated from the measured gamma-ray intensity also falls within the range of theoretical predictions. 

Importantly, these gamma-ray measurements are not easily explained by other, more common astronomical phenomena or gamma-ray emissions. Therefore, researchers consider these data a strong indication of gamma-ray emission from dark matter, which has been sought for many years. 

The  results, though, must be verified through independent analysis by other researchers. Even with this confirmation, scientists will want additional proof that the halolike radiation is indeed the result of dark matter annihilation rather than originating from some other astronomical phenomena.

Additional proof of WIMP collisions in other locations that harbor a high concentration of dark matter would bolster these initial results. Detecting the same energy gamma-ray emissions from dwarf galaxies within the Milky Way halo, for example, would support this analysis. 

So more work is needed to confirm its presence.

Tomonori Totani, 20 GeV halo-like excess of the Galactic diffuse emission and implications for dark matter annihilation, Journal of Cosmology and Astroparticle Physics (2025). On arXiv : DOI: 10.48550/arxiv.2507.07209

• ‹ Previous
• 1
• …
• 32
• 33
• 34
• 35
• 36
• …
• 1183
• Next ›
• Page