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Comment by Dr. Krishna Kumari Challa 9 hours ago

Why our immune system remembers vaccinations for decades
Long-lived immunological memory after vaccination is maintained by memory T cells that enter an energy-saving, low-metabolic state early after activation. This metabolic restraint enables them to persist for decades and rapidly respond to future infections. The principle applies broadly, including to COVID-19 vaccination, and may inform improved vaccine design.

Sina Frischholz et al, Metabolic quiescence of naive-like memory T cells precedes and maintains antigen-specific T cell memory, Nature Immunology (2026). DOI: 10.1038/s41590-026-02421-w

Comment by Dr. Krishna Kumari Challa 9 hours ago

In simple terms, quorum sensing involves chemical signals released by bacteria. Only when many bacteria have grown in a tumor is the signal strong enough to turn on the oxygen-resistant gene, ensuring it doesn't happen too soon.

In a 2023 study, researchers demonstrated that Clostridium sporogenes can be modified to tolerate oxygen. Now, in a follow-up study published in the journal ACS Synthetic Biology, they tested their quorum sensing system by making bacteria produce a green fluorescent protein.
Researchers now plan to combine the oxygen-resistant gene and the quorum-sensing timing mechanism in one bacterium and test it on a tumor in pre-clinical trials.

Sara Sadr et al, Construction and Functional Characterization of a Heterologous Quorum Sensing Circuit in Clostridium sporogenes, ACS Synthetic Biology (2025). DOI: 10.1021/acssynbio.5c00628

Part 2

Comment by Dr. Krishna Kumari Challa 9 hours ago

Engineered bacteria can consume tumors from the inside out

A research team is developing a novel tool to treat cancer by engineering hungry bacteria to literally eat tumors from the inside out. "Bacteria spores enter the tumor, finding an environment where there are lots of nutrients and no oxygen, which this organism prefers, and so it starts eating those nutrients and growing in size.
Engineered Clostridium sporogenes bacteria have been modified to survive in low-oxygen tumor environments and selectively activate oxygen resistance via quorum sensing. This approach enables the bacteria to colonize and degrade tumors from within while minimizing risk to healthy, oxygen-rich tissues. Pre-clinical trials are planned to test this targeted cancer therapy.

Key to the approach is a bacterium called Clostridium sporogenes, which is commonly found in soil and can only grow in environments with absolutely no oxygen. The core of a solid, cancerous tumor is comprised of dead cells and is oxygen-free, making it an ideal breeding ground for the bacterium to multiply.
But there is a biological catch: when the cancer-eating organisms reach the outer edges of tumors, they are exposed to low levels of oxygen and die without completing their mission to fully destroy them.

To solve that problem, the researchers first added a gene to the organism from a related bacterium that can better tolerate oxygen, enabling it to live longer near the outside of a targeted tumor.

They then found a way to activate the oxygen-resistant gene at just the right time—critical to preventing bacteria from inadvertently growing in oxygen-rich places such as the bloodstream—by leveraging a phenomenon known as quorum sensing.

Part 1

Comment by Dr. Krishna Kumari Challa 9 hours ago

AI provides a more precise time of death post-mortem

Artificial intelligence can be used to provide a more precise time of death, which could be crucial in murder investigations. The method was developed by researchers.
Artificial intelligence analyzing blood metabolites enables more precise estimation of time since death, improving accuracy to about one day even up to 13 days post-mortem. This method outperforms traditional forensic techniques and requires relatively modest data sets, making it applicable in various laboratories. Further refinement aims to enhance precision and determine the time of day of death.
When the body dies, a number of biological processes set in. Organs and tissues begin to break down, leading to changes in small molecules in the blood called metabolites. They are broken down in a predictable way that correlates with how much time has elapsed since the time of death.
This enables us to assess the actual time of death of an individual, which is very important in forensic investigations, but also to the work of the police. For example, they need to spend their resources on the right witnesses in the right period of time in the deceased person's life.
Limits of today's forensic methods
The methods currently used to determine the time of death, also known as the post-mortem interval, include body temperature, rigor mortis, and the amount of potassium in the vitreous of the eye. However, these methods yield less accurate results when a few days have passed since the time of death.

The method now developed by researchers instead uses artificial intelligence to analyze the metabolites in blood samples collected at autopsy.
Blood samples from more than 45,000 autopsies have been collected by RMV over a period of almost 10 years, resulting in a world-unique database. The samples are used to find various chemical substances such as drugs, pharmaceuticals, or toxins. But body metabolites can also be found in the blood samples. Of these 45,000 samples, 4,876 with known post-mortem interval were used to train the AI model.
The researchers showed that their new model could predict the time from death to autopsy with a precision of about one day, even for those deceased for up to 13 days. A clear improvement on current methods.
Many external factors affect body decomposition but the signal from the body's metabolites was so strong when it comes to predicting the post-mortem interval.

So the researchers' next step is to produce a data set with more precise information about the time of death, and then train models that will provide more reliable estimates of the post-mortal interval as well as be able to determine during which part of the day a death occurred.
Forensic assessments often involve puzzle-like detective work. This new tool gives us better opportunities to assess how long someone has been deceased, even when a long time has passed since their death, which is of great importance, especially in more complex cases.

Rasmus Magnusson et al, The human metabolome and machine learning improves predictions of the post-mortem interval, Nature Communications (2026). DOI: 10.1038/s41467-026-69158-w

Comment by Dr. Krishna Kumari Challa 10 hours ago

Thunderstorms conjure ghostly coronae in treetops, observed outdoors for the first time

Scientists have speculated about weak electrical discharges on plants under thunderstorms for almost a century but have never observed or measured them in the wild until now, only inferring their existence from anomalies in the electric field in forests during storms.

For the first time, researchers have observed and measured weak electrical discharges, known as coronae, on trees during thunderstorms. A new study describes the near-invisible sparkles appearing similarly on branches of several tree species up and down the U.S. East Coast during the summer of 2024, implying that thunderstorms may paint entire canopies with a scintillating blue glow, albeit too faintly for human eyes to see.

Coronae also burn the very tips of leaves. Given the ubiquity with which they may occur across forests during storms, the researchers speculated that these coronae could harm the canopy, potentially shaping the evolution of trees to limit that damage.

Lab experiments over the past half-century had at least demonstrated how they could form in the wild: The charge of a thunderstorm overhead induces an opposite charge in the ground below. That ground charge, attracted to the one above, travels toward the highest point it can reach—in this case, the tips of leaves in the treetops—through which electricity discharges, forming coronae.

In the laboratory, if you turn off all the lights, close the door and block the windows, you can just barely see the coronae. They look like a blue glow

P. J. McFarland et al, Corona Discharges Glow on Trees Under Thunderstorms, Geophysical Research Letters (2026). DOI: 10.1029/2025gl119591

Comment by Dr. Krishna Kumari Challa yesterday

Are one in 200 men really related to Genghis Khan? Maybe not, according to a new study

In present day Kazakhstan, both local folklore and genetic evidence found buried in royal tombs have shone a light on the region's ties to Genghis Khan and the Mongol Empire. New DNA analysis of ruling elites from the Golden Horde—the northwestern extension of the Mongol Empire—reveals implications for the genetic ancestry of the broader Mongolian Empire. The findings were recently published in the Proceedings of the National Academy of Sciences.

The Golden Horde was founded and ruled by Genghis Khan's eldest son, Joshi, and his descendants. According to local folklore, one of the four tombs analyzed for this study belongs to Joshi himself and houses his remains. The additional three tombs analyzed in this study belonged to other Golden Horde ruling elites and provide evidence of Mongol cultural practices blending with local culture.

Inspired, Askapuli and his archaeologist colleagues in Kazakhstan decided to investigate whether the tales were true, in collaboration with researchers at the National Institute of Genetics, Japan.

About twenty years ago, researchers traced fragments of DNA found on the Y-chromosome, called the C3* cluster, back to medieval inhabitants of the Mongolian plateau. Today, many people across central Eurasia have this C3* cluster in their genome. Some scholars have hypothesized one reason the C3* cluster is so widespread is because of the Mongol Empire's vast sphere of control. It's even fueled the popular belief that one in 200 men is related to Genghis Khan.

But this new study's data reveal a more complicated possibility: While they did find evidence of the C3* cluster in the genome of the ruling elites, it appears in the genome of modern individuals at a much lower frequency.

Ayken Askapuli et al, Genomes of the Golden Horde elites and their implications for the rulers of the Mongol Empire, Proceedings of the National Academy of Sciences (2026). DOI: 10.1073/pnas.2531003123

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Comment by Dr. Krishna Kumari Challa yesterday

Microplastics discovered in prostate tumors
Microplastic particles were detected in 90% of prostate tumor samples and at higher concentrations than in adjacent noncancerous tissue, averaging 2.5 times more plastic per gram. These findings suggest a possible association between microplastic accumulation and prostate cancer, though further research with larger cohorts is needed to clarify causality and underlying mechanisms.
Experts have found that when plastic from food packaging, cosmetics, and other sources is used, heated, or chemically treated, it can break down into smaller pieces and become ingested. People are also exposed to plastics by inhaling them from the air and by absorbing them through the skin. Past studies have identified these microplastics in nearly every human organ, as well as in bodily fluids and the placenta. However, how they may affect human health has remained poorly understood.

Analyzing tissue samples collected from 10 patients with prostate cancer, the research team identified plastic particles in 90% of tumor samples and 70% of benign tissue samples.

In addition, the cancerous tissue contained on average 2.5 times the amount of plastic as the healthy prostate tissue samples (about 40 micrograms of plastic per gram of tissue compared with 16 micrograms per gram).
This pilot study provides important evidence that microplastic exposure may be a risk factor for prostate cancer.

Microplastics Identified in Human Prostate Cancer, American Society of Clinical Oncology's Genitourinary Cancers Symposium (2026).

https://scitechdaily.com/90-of-prostate-cancer-tumors-contained-mic...

Comment by Dr. Krishna Kumari Challa yesterday

Women may face heart events at lower plaque levels than men, study finds

Less artery-clogging plaque in women's arteries did not appear to protect them from heart disease compared to men, according to a study published in Circulation: Cardiovascular Imaging. While heart disease is the leading cause of illness and death worldwide, according to the American Heart Association's 2026 Heart Disease and Stroke Statistics, women tend to have a lower prevalence of artery plaque than men, according to previous research.

The study evaluated health data for more than 4,200 adults (more than half of whom were women) to compare how quantity of plaque influenced the risk of major heart conditions. The study included people with stable chest pain and no prior history of coronary artery disease. Participants were randomized to undergo diagnostic evaluation via coronary computed tomography angiography (X-ray images of the heart and blood vessels) and followed for about two years. Key findings of the study: Fewer women had plaque in their coronary arteries than men (55% of women vs. 75% of men). Women also had a lower volume of artery plaque than men (a median of 78 mm3 among women vs. 156 mm3 in men). Despite less plaque, women were just as likely as men to die from any cause, have a non-fatal heart attack or be hospitalized for chest pain (2.3% of women vs. 3.4% of men). In addition, women faced increased heart risk at lower levels of plaque compared to men. For total plaque burden, women's risk began to rise at 20% plaque burden, while men's risk started at 28%. With increasing plaque levels, risk rose more sharply for women than for men.

The findings underscore that women are not 'protected' from coronary events despite having lower plaque volumes.

Risk in Women Emerges at Lower Coronary Plaque Burden Than in Men: PROMISE Trial, Circulation Cardiovascular Imaging (2026). DOI: 10.1161/CIRCIMAGING.125.019011

Comment by Dr. Krishna Kumari Challa yesterday

Your gut microbes can be anti-aging—scientists are uncovering how to keep your microbiome youthful
The gut microbiome changes with age, typically losing diversity and increasing inflammation-promoting bacteria, which correlates with aging. Maintaining a youthful microbiome is linked to healthier aging and longevity. Diets high in fiber and regular exercise support a beneficial microbiome, while interventions like fecal transplants, postbiotics, and targeted drugs or phages are being explored to promote healthy aging.

Comment by Dr. Krishna Kumari Challa yesterday

Why do falls rise with age? Study points to cerebellar neuron firing
Age-related declines in Purkinje cell firing in the cerebellum directly impair motor coordination, balance, and gait. Experimental reduction of Purkinje cell activity in young mice induced motor deficits, while enhancing firing in older mice improved performance. These findings highlight cerebellar neuron dysfunction as a key factor in increased fall risk with aging.
A new study has found a direct link between age-related declines in neuron activity in the cerebellum and worsening motor skills, including gait, balance and agility. While it is well known that these abilities diminish with age, this is the first research to pinpoint how changes in Purkinje cells—a key type of cerebellar neuron—drive this decline and translate into measurable changes in behaviour and physical function.
Purkinje cells process sensory input and internal signals from the body and send corrective messages that finetune movement. However, unlike other neurons, they can also spontaneously fire electrical signals. To test how aging affects this activity, the researchers examined motor coordination in mice ranging from young adults (two months old) to elderly (18 to 24 months old). Older mice performed worse on several coordination tasks, including crossing an elevated beam and staying on a rotating rod (Rotarod), mirroring motor decline in humans.
The team then recorded electrical activity from Purkinje cells and found significantly lower firing frequencies in older mice. To determine whether this caused the behavioral decline, they used a genetically targeted tool called a DREADD, a type of designer receptor that increases or decreases neuron excitability when activated.
When they turned on the DREADD for young mice, which made their Purkinje cells fire at lower rates, mimicking the older Purkinje cells, the researchers found that they jumped off the Rotarod sooner than young mice who did not have the DREADD.
The reverse was also true: when the researchers boosted neuron firing in older mice, those mice stayed on the Rotarod longer, suggesting improved motor coordination.
The researchers showed that spontaneous firing rates in older Purkinje cells are reduced, and if we reverse this, we improve coordination. This indicates that the change plays a direct role in the age-related decline of motor coordination.

Eviatar Fields et al, Cerebellar Purkinje cell firing reduction contributes to aging-related declining motor coordination in mice, Proceedings of the National Academy of Sciences (2026). DOI: 10.1073/pnas.2525795122

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