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Comment by Dr. Krishna Kumari Challa on March 6, 2025 at 12:24pm

When you get hurt matters: Circadian rhythms shown to play a role in muscle repair

The body's internal clock doesn't just dictate when we sleep—it also determines how quickly our muscles heal. A new study in mice, published today in Science Advances, suggests that muscle injuries heal faster when they occur during the body's natural waking hours.

The findings could have implications for shift workers and may also prove useful in understanding the effects of aging and obesity. 

The study also may help explain how disruptions like jetlag and daylight saving time changes impact circadian rhythms and muscle recovery.

"In each of our cells, we have genes that form the molecular circadian clock. These clock genes encode a set of transcription factors that regulate many processes throughout the body and align them with the appropriate time of day. Things like sleep/wake behaviour, metabolism, body temperature and hormones—all these are circadian.

Earlier it was found that mice regenerated muscle tissues faster when the damage occurred during their normal waking hours. When mice experienced muscle damage during their usual sleeping hours, healing was slowed.

In the current study, the researchers sought to better understand how circadian clocks within muscle stem cells govern regeneration depending on the time of day.

They found that the time of day influenced inflammatory response levels in stem cells, which signal to neutrophils—the "first responder" innate immune cells in muscle regeneration.

They  discovered that the cells' signaling to each other was much stronger right after injury when mice were injured during their wake period. This finding  is further evidence that the circadian regulation of muscle regeneration is dictated by this stem cell-immune cell crosstalk.

The scientists found that the muscle stem cell clock also affected the post-injury production of NAD+, a coenzyme found in all cells that is essential to creating energy in the body and is involved in hundreds of metabolic processes.

Next, using a genetically manipulated mouse model, which boosted NAD+ production specifically in muscle stem cells, the team of scientists found that NAD+ induces inflammatory responses and neutrophil recruitment, promoting muscle regeneration.

The findings may be especially relevant to understanding the circadian rhythm disruptions that occur in aging and obesity.

Circadian disruptions linked to aging and metabolic syndromes like obesity and diabetes are also associated with diminished muscle regeneration.

 Pei Zhu et al, Immunomodulatory role of the stem cell circadian clock in muscle repair, Science Advances (2025). DOI: 10.1126/sciadv.adq8538

Comment by Dr. Krishna Kumari Challa on March 6, 2025 at 12:10pm

The researchers previously screened 810 genes in mice and found 15 that had an effect on cancer metastasis. In particular, they found that mice lacking a gene which produces a protein called ARHGEF1 had less metastasis of various primary cancers to the lungs and liver.

The researchers determined that ARHGEF1 suppresses a type of immune cell called a T cell, which can recognize and kill metastatic cancer cells.

To develop treatments to take advantage of this discovery, they needed to find a way for drugs to target it. The scientists traced signals in the cell to determine that ARHGEF1 is switched on when T cells are exposed to a clotting factor called thromboxane A2 (TXA2).

This was an unexpected revelation for the scientists, because TXA2 is already well-known and linked to how aspirin works.

TXA2 is produced by platelets—a cell in the blood stream that helps blood clot, preventing wounds from bleeding, but occasionally causing heart attacks and strokes. Aspirin reduces the production of TXA2, leading to the anti-clotting effects which underlie its ability to prevent heart attacks and strokes.

This new research found that aspirin prevents cancers from spreading by decreasing TXA2 and releasing T cells from suppression. They used a mouse model of melanoma to show that in mice given aspirin, the frequency of metastases was reduced compared to control mice, and this was dependent on releasing T cells from suppression by TXA2.
Aspirin, or other drugs that could target this pathway, have the potential to be less expensive than antibody-based therapies, and therefore more accessible globally.
In a small proportion of people, aspirin can cause serious side effects, including bleeding or stomach ulcers. Therefore, it is important to understand which people with cancer are likely to benefit and always talk to your doctor before starting aspirin, the researchers say.

Rahul Roychoudhuri, Aspirin prevents metastasis by limiting platelet TXA2 suppression of T cell immunity, Nature (2025). DOI: 10.1038/s41586-025-08626-7. www.nature.com/articles/s41586-025-08626-7

Part 2

Comment by Dr. Krishna Kumari Challa on March 6, 2025 at 12:08pm

Scientists discover how aspirin could prevent some cancers from spreading

Scientists have uncovered the mechanism behind how aspirin could reduce the metastasis of some cancers by stimulating the immune system. In the study, published in Nature, the scientists say that discovering the mechanism will support ongoing clinical trials, and could lead to the targeted use of aspirin to prevent the spread of susceptible types of cancer, and to the development of more effective drugs to prevent cancer metastasis.

The scientists caution that, in some people, aspirin can have serious side effects and clinical trials are underway to determine how to use it safely and effectively to prevent cancer spread, so people should consult their doctor before starting to take it.

Studies of people with cancer have previously observed that those taking daily low-dose aspirin have a reduction in the spread of some cancers, such as breast, bowel, and prostate cancers, leading to ongoing clinical trials. However, until now it wasn't known exactly how aspirin could prevent metastases.

Scientists  were investigating the process of metastasis, because, while cancer starts out in one location, 90% of cancer deaths occur when cancer spreads to other parts of the body.

The scientists wanted to better understand how the immune system responds to metastasis, because when individual cancer cells break away from their originating tumor and spread to another part of the body they are particularly vulnerable to immune attack.

The immune system can recognize and kill these lone cancer cells more effectively than cancer cells within larger originating tumors, which have often developed an environment that suppresses the immune system.

Part 1

Comment by Dr. Krishna Kumari Challa on March 6, 2025 at 11:05am

Microscopic particles of 'active matter' dance to the tune of electrochemical reactions

A new study has revealed a coordinated dance of microscopic particles—breaking up and clustering back together in just seconds—after receiving electrical and chemical stimuli. This work represents a new class of materials that mimic the behaviors of living organisms, known as "active matter."

Like the skins of chameleons and octopuses, which respond to external stimuli by changing colors, active matter can display dynamic and autonomous behavior including motility, assembly and swarming. The study published in Nature Communications, revealed a new mechanism to activate these properties within seconds.

 Medha Rath et al, Transient colloidal crystals fueled by electrochemical reaction products, Nature Communications (2025). DOI: 10.1038/s41467-025-57333-4

Comment by Dr. Krishna Kumari Challa on March 6, 2025 at 10:14am

Imagine a world where the fundamental constants are different and set the upper limit for TC at a mere millionth of a Kelvin. In such a universe, superconductivity would be undetectable, and we would never have discovered it. Conversely, in a universe where the limit is a million Kelvin, superconductors would be common—even in your electric kettle.

The wire would superconduct instead of heating up. Boiling water for tea would be a very different challenge. It therefore appears that the very reason the community is busy chasing up a room-temperature superconductor is that our fundamental constants set the upper limit of TC in the range 100–1000 K (the range of planetary conditions) where our "room" temperature is.
This research not only advances our understanding of superconductivity but also highlights the delicate balance of the constants that make our universe—and life within it—possible. For scientists and engineers, this work also provides a renewed sense of direction.

 Kostya Trachenko et al, Upper bounds on the highest phonon frequency and superconducting temperature from fundamental physical constants, Journal of Physics: Condensed Matter (2025). DOI: 10.1088/1361-648X/adbc39. On arXiv: DOI: 10.48550/arxiv.2406.08129

Part 2

Comment by Dr. Krishna Kumari Challa on March 6, 2025 at 10:13am

Room-temperature superconductors: Fundamental constants suggest they could exist within our universe

In a new development that could help redefine the future of technology, a team of physicists has uncovered a fundamental insight into the upper limit of superconducting temperature.

This research, accepted for publication in the Journal of Physics: Condensed Matter, suggests that room-temperature superconductivity—long considered the "holy grail" of condensed matter physics—may indeed be possible within the laws of our universe.

Superconductors, materials that can conduct electricity without resistance, have the potential to revolutionize energy transmission, medical imaging, and quantum computing. However, until now, they have only functioned at extremely low temperatures, making them impractical for widespread use. The race to find a superconductor that works at ambient conditions has been one of the most intense and elusive pursuits in modern science.

The researchers  reveal that the upper limit of superconducting temperature TC is intrinsically linked to the fundamental constants of nature—the electron mass, electron charge, and the Planck constant.

Constants such as these govern everything from the stability of atoms to the formation of stars and synthesis of carbon and other elements essential to life. The team's finding shows that the upper limit ranges from hundreds to a thousand Kelvin—a range that comfortably includes room temperature.

This discovery tells us that room-temperature superconductivity is not ruled out by fundamental constants.

The results have already been independently confirmed in a separate study, adding weight to the team's conclusions. But the implications go even further. By exploring how different values of these fundamental constants could alter the limits of superconductivity, the researchers have opened a fascinating window into the nature of our universe.

Part 1

Comment by Dr. Krishna Kumari Challa on March 6, 2025 at 8:37am

Bacteria use nano-spearguns to retaliate against attacks

Some bacteria deploy tiny spearguns to retaliate against rival attacks. Researchers  have mimicked attacks by poking bacteria with an ultra-sharp tip. Using this approach, they have uncovered that bacteria assemble their nanoweapons in response to cell envelope damage and rapidly strike back with high precision.

The research is published in the journal Science Advances.

In the world of microbes, peaceful coexistence goes hand in hand with fierce competition for nutrients and space. Certain bacteria outcompete rivals and fend off attackers by injecting them with a lethal cocktail using tiny, nano-sized spearguns, known as type VI secretion systems (T6SS).

Bacteria respond to cell envelope damage. 

Using atomic force microscopy (AFM), researchers have been able to mimic a bacterial T6SS attack. With the needle-like, ultra-sharp AFM tip, they could touch the bacterial surface, and by gradually increasing the pressure, puncture the outer and the inner membranes in a controlled manner.

In combination with fluorescence microscopy, the researchers revealed that the bacteria responded to outer membrane damage.

Within ten seconds the bacteria assembled their T6SS, often repeatedly, at the site of damage and fired back with pinpoint accuracy.

In the microbial ecosystem, survival is all about strategy, and Pseudomonas aeruginosa has certainly mastered the art of defense. Their targeted and swift retaliation against local attacks minimizes misfiring and optimizes the cost-benefit ratio.

This clever tactic gives Pseudomonas a survival advantage, enabling it to incapacitate attackers and thrive in diverse and often challenging environments.

Mitchell Brüderlin et al, Pseudomonas aeruginosa assembles H1-T6SS in response to physical and chemical damage of the outer membrane, Science Advances (2025). DOI: 10.1126/sciadv.adr1713

Comment by Dr. Krishna Kumari Challa on March 6, 2025 at 8:26am

Packets of freeze-dried bacteria can grow bio-cement on demand

Cement manufacturing and repair could be significantly improved by using biocement-producing bacteria, but growing the microbes at construction sites remains a challenge. Now, researchers report a freeze-drying approach in ACS Applied Materials & Interfaces that preserves the bacteria, potentially allowing construction workers to ultimately use powder out of a packet to quickly make tiles, repair oil wells or strengthen the ground for makeshift roads or camps.

Soil stabilization and concrete repair are major challenges facing civil engineers. Recently, researchers have shifted their attention to a tiny bacterium called Sporosarcina pasteurii that can produce a form of calcium mineral called biocement. The microbes break down urea and form ammonium and carbonate. Then, with the addition of calcium, the result is calcium carbonate, which glues sand and soil particles together or repairs cracks in existing concrete structures.

To make biocement for construction projects, the bacteria currently must be grown onsite with special equipment and technical know-how. So, researchers wanted to develop a way to preserve S. pasteurii in a shelf-stable format that would be easy for construction workers to use.

They were  inspired by manufacturers who freeze-dry biological components and add them to fertilizers. The researchers suspended the bacteria in different solutions and tested how well the microbes survived freezing. They found that sucrose protected the microbes best compared to other types of protectants. After freezing, the bacteria were dried and then stored in resealable plastic bags. Sucrose-treated S. pasteurii remained viable for at least three months.

Further laboratory testing showed that the sucrose-preserved, freeze-dried bacteria could be used to cement sand in 3D-printed cylindrical molds. The researchers prepared separate columns with play sand, like that used in children's sandboxes, and natural sandy soil taken from the ground. Then, when the columns were sprayed several times with calcium chloride and urea, the bacteria produced biocement. The biocement in the columns made with play sand was stronger than the biocement formed with soil, and most of the biocement samples could be removed from the play sand molds.

Matthew J. Tuttle et al, Shelf-Stable Sporosarcina pasteurii Formulation for Scalable Laboratory and Field-Based Production of Biocement, ACS Applied Materials & Interfaces (2025). DOI: 10.1021/acsami.4c15381

Comment by Dr. Krishna Kumari Challa on March 5, 2025 at 10:49am

The study found that the type of land plays a significant role in the density of lightning strikes. Firstly, North India (NI) generally experienced more lightning than Northeast India (NEI). However, the timing differs: NI sees a peak in lightning during the monsoon season (June to September), while NEI is more prone to lightning strikes during the pre-monsoon months (March to May).

Areas with lots of human activity, like farmland and cities, were also shown to have more lightning strikes. Without vegetation covering it around the year, the ground over farmlands heats up quickly, creating the perfect conditions for thunderstorms. Natural landscapes, like forests and grasslands, were shown to have moderate lightning activity, showing us that vegetation, which helps maintain high soil moisture, plays a role in lightning occurrences. Some natural areas, like savannas (grasslands with scattered trees) and wetlands, can also be lightning hotspots.

The mountains also matter. The research revealed that lightning is more common in the foothills of the Himalayas. It is likely caused by surface heating, where moisture-filled air gets pushed upwards, and orographic lifting (mountain formations) in Meghalaya. The height above sea level is also important. Most lightning happens at lower altitudes (below 1600 feet), and the frequency decreases as you go higher up the mountains, especially in North India. Finally, the study found that as farmland and cities expand, lightning activity tends to increase in those areas.

The study shows us that lightning isn't just a random event, instead, it's shaped by the landscape, the vegetation, and even human activities. Understanding these connections can guide safety measures and help farmers and city planners make informed decisions.

https://www.sciencedirect.com/science/article/abs/pii/S136468262500...

part2

Comment by Dr. Krishna Kumari Challa on March 5, 2025 at 10:48am

Lightning and Landscapes: How Land and Weather Shape Lightning in India

Lightning is one of the most spectacular natural phenomena, having captivated humans for centuries, sparking both awe and fear.

Today, scientists know exactly why lightning strikes, but predicting where it will strike is much more difficult due to all the factors at play. In fact, the word has become synonymous with unpredictability. But scientists all over the world are trying to uncover these mysteries.

In a new study, researchers have studied how the landscape affects lightning strikes. They have delved into understanding the frequency of lightning in North India (NI) and North-East India (NEI), discovering how land use and topography might predict when and where these electrical bursts will occur.

For their study, the researchers poured thorough data from the Lightning Imaging Sensor (LIS) on the Tropical Rainfall Measuring Mission (TRMM) satellite, recording the location and frequency of lightning strikes between 2001 and 2014. They then combined this lightning data with information about the different types of land in the area - forests, farms, cities, and so on -  obtained from another satellite, Moderate Resolution Imaging Spectroradiometer (MODIS). For topographical details, they consulted the Shuttle Radar Topography Mission or SRTM—a source of detailed 3D maps of Earth's surface.

They also looked at weather-related factors like temperature, humidity, and something called Convective Available Potential Energy (CAPE). CAPE measures how unstable the atmosphere is and how likely it is to produce thunderstorms. They also analysed total cloud cover liquid water (TCCLW) and total cloud cover ice water (TCCIW) along with lightning flash rate density (LFRD) to determine the local temperatures and amount of moisture in the air. They then used computer programs to classify each strike, overlaying their locations on MODIS images to see which land types were struck by lightning. By examining topographical elevations, they categorised these lightning locations by height, revealing patterns at different altitudes.

Part 1. 

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