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Comment by Dr. Krishna Kumari Challa on December 14, 2025 at 8:51am

Fossils reveal anacondas have been giants for over 12 million years

Researchers  analyzed giant anaconda fossils from South America to deduce that these tropical snakes reached their maximum size 12.4 million years ago and have remained giants ever since.

Many animal species that lived 12.4 to 5.3 million years ago, in the period known as the "Middle to Upper Miocene," were much bigger than their modern relatives due to warmer global temperatures, extensive wetlands and an abundance of food.

While other Miocene giants—like the 12-meter caiman (Purussaurus) and the 3.2-meter giant freshwater turtle (Stupendemys)—have since gone extinct, anacondas (Eunectes) bucked the trend by surviving as a giant species.

Anacondas are among the largest living snakes in the world. They are usually four to five meters long and in rare cases can reach seven meters.

The team measured 183 fossilized anaconda backbones, representing at least 32 snakes, discovered in Falcón State in Venezuela, South America. Combining these measurements with fossil data from other sites in South America allowed them to calculate that ancient anacondas would have been four to five meters long. This matches the size of anacondas that exist today. 

An early origin of gigantism in anacondas (Serpentes: Eunectes) revealed by the fossil record, Journal of Vertebrate Paleontology (2025). DOI: 10.1080/02724634.2025.2572967

Comment by Dr. Krishna Kumari Challa on December 14, 2025 at 8:51am

Ant brood signal deadly infection in altruistic self-sacrifice

Terminally ill ant pupae emit specific non-volatile odor signals that prompt worker ants to remove and disinfect them, preventing pathogen spread within the colony. This targeted signaling occurs only when infections are uncontrollable, ensuring colony health while minimizing unnecessary sacrifice, and parallels immune responses in multicellular organisms.

Sylvia Cremer, Altruistic disease signalling in ant colonies, Nature Communications (2025). DOI: 10.1038/s41467-025-66175-z. www.nature.com/articles/s41467-025-66175-z

Comment by Dr. Krishna Kumari Challa on December 14, 2025 at 8:50am

Electric vehicle high-nickel batteries: Fundamental cause of performance degradation identified

Succinonitrile (CN₄), an electrolyte additive previously used to enhance stability in lithium-ion batteries, has been identified as a primary cause of rapid degradation in high-nickel batteries. CN₄ binds strongly to nickel ions, disrupting the cathode’s protective layer, causing structural damage, and accelerating performance loss.

Seung Hee Han et al, Unveiling Bidentate Nitrile-Driven Structural Degradation in High-Nickel Cathodes, ACS Energy Letters (2025). DOI: 10.1021/acsenergylett.5c02845

Comment by Dr. Krishna Kumari Challa on December 14, 2025 at 8:49am

Deadly Asian floods are no fluke.

They're a climate warning, scientists say Southeast Asia is experiencing increasingly severe and unpredictable floods and storms, consistent with climate change projections. The region is warming nearly twice as fast as the global average, intensifying extreme weather events. Governments are struggling to prepare for and respond to these disasters, which are exacerbated by deforestation and unregulated development. Economic losses are substantial, while climate finance remains insufficient.
Climate patterns last year helped set the stage for 2025's extreme weather.Atmospheric levels of heat-trapping carbon dioxide jumped by the most on record in 2024. That "turbocharged" the climate, the United Nation's World Meteorological Organization says, resulting in more extreme weather.Asia is bearing the brunt of such changes, warming nearly twice as fast as the global average. Scientists agree that the intensity and frequency of extreme weather events are increasingWarmer ocean temperatures provide more energy for storms, making them stronger and wetter, while rising sea levels amplify storm surges While the total number of storms may not dramatically increase, their severity and unpredictability will What we're seeing in the region is dramatic and it's unfortunately a stark reminder of the consequences of the climate crisis, scientists conclude.
Source: News Agenices

Comment by Dr. Krishna Kumari Challa on December 14, 2025 at 8:48am

NASA discovers new bacteria 'playing dead'

New research conducted on a NASA-discovered bacterium shows the microbe is capable of entering an extreme dormant state, essentially "playing dead" to survive in some of the cleanest environments on Earth. 

The finding could potentially reshape how scientists think about microbial survival on spacecraft and the challenges of preventing contamination during missions to space. Preventing contamination matters because it helps keep space missions safe, while ensuring that any signs of life spotted elsewhere in the solar system can be trusted.

It shows that some microbes can enter ultra-low metabolic states that let them survive extremely austere environments, including clean rooms that naturally select for the hardiest organisms.

The fact that this bacterium can intentionally suspend its metabolism makes survival on spacecraft surfaces or during deep-space cruise more plausible than previously assumed .

What stood out most to me is that these microbes don't form spores .  Seeing a non-spore-former achieve comparable robustness through metabolic shutdown alone suggests there are additional, underappreciated survival mechanisms in bacteria that we haven't fully characterized.

Madhan Tirumalai et al, Tersicoccus phoenicis (Actinobacteria), a spacecraft clean room isolate, exhibits dormancy, Microbiology Spectrum (2025). DOI: 10.1128/spectrum.01692-25

Comment by Dr. Krishna Kumari Challa on December 14, 2025 at 8:48am

'Brainquake' phenomenon links psychotic states to chaotic information flow

Some psychiatric disorders, particularly schizophrenia and bipolar disorder (BP), can prompt the emergence of so-called psychotic states, mental states characterized by distorted thinking patterns, altered perceptions and unusual beliefs. Detecting and diagnosing these states is not always easy, as they often overlap with the symptoms of other mental health disorders, and reliable methods to identify psychosis are still lacking.

Researchers  recently carried out a study aimed at further exploring the neural signatures of psychotic states. Their findings, published in Molecular Psychiatry, suggest that the activity in the brains of individuals who are experiencing psychosis is significantly more random, following patterns that hint at an unstable flow of information.

As part of their study, the researchers scanned the brains of individuals diagnosed with BP or schizophrenia using fMRI.  They looked at the complexity of the activity patterns in the participants' brains. Moreover, they tried to understand how information flowed between different brain regions, used tools rooted in information theory. Specifically, they tried to measure the overlapping of information (i.e., redundancy) and combination of information (i.e., synergy) within specific brain networks. 

To further investigate these disruptions, they estimated brain network connectivity using redundancy and synergy measures, aiming to assess the integration and segregation of topological information in the psychotic brain. Their findings reveal a disruption in the balance between redundant and synergistic information, a phenomenon they term brainquake in this study, which highlights the instability and disorganization of brain networks in psychosis.

They found that this "brainquake" disruption resulted in a widespread instability across several neural networks involved in the processing of emotions and sensory information, as well as memory and other mental functions. 

This  exploration of higher-order topological functional connectivity reveals profound disruptions in brain information integration, wrote the authors in their research paper.

Aberrant information interactions were observed across both cortical and subcortical ICNs. They specifically identified the most easily affected irregularities in the sensorimotor, visual, temporal, default mode, and fronto-parietal networks, as well as in the hippocampal and amygdalar regions, all of which showed disruptions. 

The findings underscore the severe impact of psychotic states on multiscale critical brain networks, suggesting a profound alteration in the brain's complexity and organizational states.

Qiang Li et al, Spatiotemporal complexity in the psychotic brain, Molecular Psychiatry (2025). DOI: 10.1038/s41380-025-03367-5. 

Comment by Dr. Krishna Kumari Challa on December 14, 2025 at 8:45am

How volcanic eruptions set off a chain of events that brought the Black Death to Europe
Volcanic eruptions around 1345 triggered consecutive years of cooling, leading to crop failures and famine in southern Europe. To prevent starvation, Italian city states imported grain from the Black Sea, inadvertently introducing Yersinia pestis via infected fleas on ships. This sequence of climate, agricultural, and trade events enabled the Black Death's rapid spread across Europe.

Comment by Dr. Krishna Kumari Challa on December 14, 2025 at 8:45am

How volcanic eruptions set off a chain of events that brought the Black Death to Europe

Clues contained in tree rings have identified mid-14th-century volcanic activity as the first domino to fall in a sequence that led to the devastation of the Black Death in Europe. 

Researchers  have used a combination of climate data and documentary evidence to paint the most complete picture to date of the "perfect storm" that led to the deaths of tens of millions of people, as well as profound demographic, economic, political, cultural and religious change.

Their evidence suggests that a volcanic eruption—or cluster of eruptions—around 1345 caused annual temperatures to drop for consecutive years due to the haze from volcanic ash and gases, which in turn caused crops to fail across the Mediterranean region. To avoid riots or starvation, Italian city states used their connections to trade with grain producers around the Black Sea.

This climate-driven change in long-distance trade routes helped avoid famine, but in addition to life-saving food, the ships were carrying the deadly bacterium that ultimately caused the Black Death, enabling the first and deadliest wave of the second plague pandemic to gain a foothold in Europe.

This is the first time that it has been possible to obtain high-quality natural and historical proxy data to draw a direct line between climate, agriculture, trade and the origins of the Black Death. The results are reported in the journal Communications Earth & Environment. 

The researchers say the "perfect storm" of climate, agricultural, societal and economic factors after 1345 that led to the Black Death can also be considered an early example of the consequences of globalization.

Although the coincidence of factors that contributed to the Black Death seems rare, the probability of zoonotic diseases emerging under climate change and translating into pandemics is likely to increase in a globalized world.

The researchers say that resilience to future pandemics requires a holistic approach to address a wide spectrum of health threats. Modern risk assessments should incorporate knowledge from historical examples of the interactions between climate, disease and society. 

Climate-driven changes in Mediterranean grain trade mitigated famine but introduced the Black Death to medieval Europe, Communications Earth & Environment (2025). DOI: 10.1038/s43247-025-02964-0

Comment by Dr. Krishna Kumari Challa on December 14, 2025 at 8:45am

Human hair grows through 'pulling' not pushing

Scientists have found that human hair growth does not grow by being pushed out of the root; it's actually pulled upward by a force associated with a hidden network of moving cells. The findings challenge decades of textbook biology and could reshape how researchers think about hair loss and regeneration.

Researchers  used advanced 3D live imaging to track individual cells within living human hair follicles kept alive in culture. The study, published in Nature Communications, shows that cells in the outer root sheath—a layer encasing the hair shaft—move in a spiral downward path within the same region from where the upward pulling force originates.

To test this, the researchers blocked cell division inside the follicle, expecting hair growth to stop. Instead, growth continued nearly unchanged. But when they interfere with actin—a protein that enables cells to contract and move—the hair growth rate dropped by more than 80%. 

Computer models confirmed that this pulling force, correlated with coordinated motion in the follicle's outer layers, was essential to match the observed speeds of hair movement. 

The researchers  used a novel imaging method allowing 3D time lapse microscopy in real-time. While static images provide mere isolated snapshots, 3D time-lapse microscopy is indispensable for truly unraveling the intricate, dynamic biological processes within the hair follicle, revealing crucial cellular kinetics, migratory patterns, and rate of cell divisions that are otherwise impossible to deduce from discrete observations. This approach made it possible to model the forces generated locally.

This reveals that hair growth is not driven only by cell division—instead, the outer root sheath actively pulls the hair upward. This new view of follicle mechanics opens fresh opportunities for studying hair disorders, testing drugs and advancing tissue engineering and regenerative medicine.

  The study also highlights the growing role of biophysics in biology, showing how mechanical forces at microscopic scale shape the organs we see every day. 

Nicolas Tissot et al, Mapping cell dynamics in human ex vivo hair follicles suggests pulling mechanism of hair growth, Nature Communications (2025). DOI: 10.1038/s41467-025-65143-x

Comment by Dr. Krishna Kumari Challa on December 14, 2025 at 8:44am

Single enzyme failure found to drive neuron loss in dementia 

 Loss of function in the enzyme glutathione peroxidase 4 (GPX4) disrupts neuronal protection against ferroptosis, leading to neuron death and early-onset dementia. A specific GPX4 mutation impairs its ability to neutralize lipid peroxides at the cell membrane, triggering neurodegeneration. Inhibiting ferroptosis can slow this process in experimental models.

Svenja M. Lorenz et al, A fin-loop-like structure in GPX4 underlies neuroprotection from ferroptosis, Cell (2025). DOI: 10.1016/j.cell.2025.11.014

https://medicalxpress.com/news/2025-12-enzyme-failure-neuron-loss-d...

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