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Comment by Dr. Krishna Kumari Challa 2 hours ago

Mars-like conditions fail to kill some Earth pathogens, experiments suggest

Microorganisms from our planet could survive on celestial bodies where water is present, such as Mars. That is the conclusion of researchers after experiments with simulated space conditions. Our immune system reacts less effectively to pathogens that have undergone such a simulated space journey.
Earth extremophiles, especially yeasts, withstand simulated lunar, Martian, and icy moon conditions via enhanced DNA repair and protective responses. Human pathogens such as Klebsiella pneumoniae survive Mars-like exposure, become smaller, and elicit weaker immune cell responses. Simulated lunar and Martian regolith damage lung barriers and promote infection more than terrestrial sand.
Researchers also studied several well-known human pathogens, such as the bacterium Klebsiella pneumoniae, which can cause pneumonia. They observed that these pathogens shrank after a simulated trip to Mars, yet survived it. In laboratory experiments, immune cells from human blood responded less strongly to these shrunken pathogens.

This is important news for astronauts, who already face declining health in space and must therefore be extra cautious about infections. Space travel places heavy strain on the immune system because of the lack of a normal day-night rhythm, poor diet, disrupted gut function, DNA damage from radiation, limited social interaction and confinement in a small space.
In addition, astronauts must be wary of dust (regolith) from the moon and Mars.
Material from Mars, and even more so from our moon, damages the protective layer of the lungs and causes infections. Earth material usually does not.

Tommaso Zaccaria, Dissertation title: Life beyond Earth: microbial survival and immune health in space. Supervisors: Prof. Dr. M.G. Netea and Prof. Dr. M.I. de Jonge. Co supervisors: Dr. P. Rettberg and Dr. K. Beblo Vranesevic (both German Aerospace Center, Germany).

Comment by Dr. Krishna Kumari Challa 2 hours ago

Jumping gene caught moving between species in first direct observation

Genes are not passed on exclusively from parents to their offspring. Some are mobile and can also jump to other species, as researchers have now shown. The direct observation of a jumping gene provides the first evidence that such genes can transfer from one species to another—from predator to prey. The study is published in the journal Scientific Reports.

Jumping genes are parasites in the genetic material of bacteria, plants, animals and humans. They are released into the cell as small RNA molecules from ribonucleic acid (RNA) and possess complex mechanisms for inserting themselves into other parts of the genetic material within the cell, thereby often conferring new properties on the cell and accelerating evolution. There are also jumping genes that free themselves from the RNA using an RNA enzyme. These ribozymes, or self-splicing introns, are a special group of jumping genes.

It is more difficult for a gene to jump into another cell or another species. Phylogenetic analyses of genes show that such jumps have taken place. Until now, it had been assumed that, for this to happen, the jumping genes traveled as 'hitchhikers' in the genomes of plasmids or viruses. Now,  researchers have made  this surprising observation.

Mobile self-splicing intron RNA from the predatory bacterium Candidatus Velamenicoccus archaeovorus was directly visualized in both predator cells and dead Methanothrix soehngenii cells, demonstrating horizontal transfer from predator to prey. The intron persists as stable circular RNA, indicating a plasmid- and virus-independent route for interspecies gene transfer that can accelerate microbial evolution.

Jana Kizina et al, Mobile intron RNA from a bacterial predator accumulates in dead archaeal cells, Scientific Reports (2026). DOI: 10.1038/s41598-026-51721-6

Comment by Dr. Krishna Kumari Challa on Sunday

Nonsurgical procedure provides lasting relief for knee pain, finds study

Osteoarthritis is the most common form of arthritis. It causes inflammation, stiffness, reduced mobility and sensory nerve pain. According to the World Health Organization, knee osteoarthritis affects more than 365 million adults worldwide and is one of the leading contributors to disability.

Embolization of abnormal blood vessels using rapidly resorbable gelatin-based microspheres is safe and provides significant, lasting pain relief and functional improvement for patients with osteoarthritis-related knee pain, according to a new study published in Radiology.
Genicular artery embolization (GAE) is an emerging minimally invasive treatment that targets abnormal blood vessels using superselective embolization.

In an osteoarthritic knee, these abnormal vessels build up around the joint and drive inflammation and pain. During GAE, an interventional radiologist guides a thin catheter directly to each affected vessel and injects tiny particles to block it, calming the inflammation and easing the pain without surgery.
In their trials, researchers noticed a significant drop in pain and a significant increase in function, including sports and recreation and daily activity.
"Most importantly, their quality of life significantly increased."
Genicular artery embolization with rapidly resorbable gelatin microspheres in 194 patients with knee osteoarthritis was technically successful in all 239 procedures, with only mild, self-limited adverse events in 6.7%. Pain scores decreased from 7 to 3 over 12 months, functional and quality-of-life scores improved beyond clinically important thresholds in 80%, indicating durable, clinically meaningful benefit.

Florian Nima Fleckenstein et al, Genicular Artery Embolization Using Rapidly Resorbable Gelatin-based Microspheres for Osteoarthritis-related Knee Pain, Radiology (2026). DOI: 10.1148/radiol.253312 , pubs.rsna.org/doi/10.1148/radiol.253312

Comment by Dr. Krishna Kumari Challa on Saturday

Fish oil supplements may not prevent Alzheimer's-related decline, clinical trial suggests
A two-year randomized, placebo-controlled trial in 365 older adults at elevated Alzheimer’s risk found that 2,000 mg/day DHA increased cerebrospinal fluid DHA by 17% but did not improve cognition or memory, nor prevent hippocampal atrophy. Results do not support high-dose fish oil supplements for Alzheimer’s prevention; broader lifestyle measures remain primary for risk reduction.

eBioMedicine (2026). www.thelancet.com/journals/EBI … (26)00198-2/fulltext

Comment by Dr. Krishna Kumari Challa on Saturday

Bending forward and walking a lot at work may raise miscarriage risk in early pregnancy

Bending forward and, to a lesser extent, walking a lot at work in early pregnancy may raise the risk of miscarriage, finds a large study of more than 470,000 Danish women, published online in the journal Occupational and Environmental Medicine.
Each additional hour of bending forward, particularly at a 30-degree angle, was associated with a 36% higher risk, while each additional hour of walking was associated with an 18% higher risk, although the pattern was consistent only for bending forward, the findings show.

Miscarriage is relatively common, affecting around 15% of women. Risk factors include parental age, smoking, night shift work, and exposure to air pollution and various chemical compounds, note the researchers.

In >800,000 Danish pregnancies, occupational standing, walking, and especially forward bending in early pregnancy were associated with increased miscarriage risk. Each additional hour of bending ≥30° correlated with ~36% higher risk, walking with 18%, and standing with 3%, with a clear dose–response only for bending.

Occupational standing, walking and forward bending during pregnancy and the risk of miscarriage: a Danish nationwide, register-based, cohort study, Occupational and Environmental Medicine (2026). DOI: 10.1136/oemed-2025-110712

Comment by Dr. Krishna Kumari Challa on Saturday

Animals communicate to work together across species boundaries

An international team of researchers have published a new review in Animal Behaviour revealing how communication enables cooperation between different animal species. The review, titled "The ecology and evolution of cues and signals in animal interspecies cooperation," highlights how movements, visual displays, calls, and other behavioural cues and signals help partners coordinate interactions and align interests across species boundaries.

From birds guiding humans to bees' nests in return for access to beeswax, to cleaner fish removing ectoparasites from larger reef fishes in exchange for a meal, cooperation between species occurs across a remarkable range of ecological settings. By gathering examples from birds, fish, insects and mammals, the authors highlight the diverse ways that animals exchange information to organize their actions and sustain mutually beneficial partnerships.

Communication via visual, acoustic, chemical, tactile, and multimodal cues enables interspecies partners to coordinate actions, access shared or exchanged resources, and limit exploitation. Signals range from stable, stereotyped displays to context-dependent, learned behaviours and can evolve from noncommunicative cues or behaviours in other contexts, illuminating the coevolution and flexibility of cooperative interactions across taxa.

Cues and signals help animals identify cooperative partners, initiate interactions, and ensure they benefit from the partnership. Because interacting with members of another species can carry risks, communication is also important for avoiding individuals that might exploit them.
Many species rely on multiple senses to improve communication, and the review suggests that focusing only on obvious visual signals may overlook important ways animals exchange information across species.
The review also explores how communication systems between species may evolve. Some signals begin as simple cues, features or behaviors that influence how others respond, even though they did not originally evolve for communication.

Over time, these cues can develop into clear signals. Other signals originate as behaviours used in different contexts, such as settling conflicts or caring for young, before being adapted for communication in interspecies cooperation.

K. Dunkley et al, The ecology and evolution of cues and signals in animal interspecies cooperation, Animal Behaviour (2026). DOI: 10.1016/j.anbehav.2026.123611

Comment by Dr. Krishna Kumari Challa on Saturday

The Sun may not engulf Earth after all, scientists say

The Earth may not be engulfed by the expanding fireball of the dying sun, which has long been assumed to be our home planet's ultimate fate, according to scientists.
New tidal-dissipation models and constraints on solar mass loss suggest the Sun’s future expansion will likely not engulf Earth or Mars, as reduced tidal dissipation and stronger mass loss allow their orbits to expand beyond the solar radius. Mercury and Venus remain destined for engulfment, and the Sun will ultimately evolve into a cooling white dwarf.
Don't worry: This is not expected to happen for another 5 billion years, long after all life on Earth has been wiped out.

When the sun burns through all of the hydrogen in its core, it will go through two immense expansion phases: first becoming a red giant, then, when its helium is spent, an "AGB" star.

This fiery death will bring about some significant changes back here on Earth.

As the sun grows, increasing gravitational forces will pull the Earth toward it.

For the Earth and the moon, this force creates the push and pull of the tides in our oceans. The energy from these tides, which dissipates at the bottom of the ocean, slows Earth's rotation and gradually pushes the moon away from us.

As the sun expands and its blistering surface approaches Earth, intense tidal waves will stir within the star. When they dissipate, they will pull Earth into its doomed embrace.

However, the growing sun will also lose a lot of its mass due to stellar wind, which pushes our planet farther away.

"Earth's fate depends on a delicate balance between these two effects," say the scientists.
If tidal interactions predominate, Earth is engulfed by the sun. If the sun's mass loss predominates, Earth escapes into an orbit larger than the radius of its star.

M. Esseldeurs et al, The fate of Earth during the Sun's giant phases, Astronomy & Astrophysics (2026). DOI: 10.1051/0004-6361/202660576

Comment by Dr. Krishna Kumari Challa on Saturday

Palm oil, coconut and soybean drive more species extinction than previously thought

Oils from crops such as coconut, palm oil and soybean are used in a range of applications, from cosmetics and makeup to margarine and spreads, and from medicines to animal feed. These oil crops, as they are known, are increasingly consumed and cultivated. This has an impact on the environment. But what exactly is that impact?

Tropical regions are especially impacted, with agricultural land use causing significant biodiversity loss. This is due not only to the fact that oil crops such as oil palm and coconut are exclusive to these regions, but also because they support high biodiversity and typically yield less per unit of land. As a result, there is often a need for  agricultural expansion, which can lead to ecosystem destruction, such as deforestation.
Global analysis of 19 oil crops attributes about 75% of oil‑crop–driven biodiversity loss to oil palm, soybean, and coconut. Biodiversity loss from these crops increased ~80% between 1995 and 2020, concentrated in tropical regions and strongly driven by consumption in other countries, notably the EU, China, and the US. Mitigation requires reduced deforestation and more biodiversity‑friendly production.

Oil crop supply chains drive rising global biodiversity loss and outsource impacts to the tropics, Nature Food (2026). DOI: 10.1038/s43016-026-01375-4

Comment by Dr. Krishna Kumari Challa on Saturday

In a brained animal, sensing a poke might involve nerves; here, the entire epithelium seems to have that built in. It's as if a crawling baby, upon feeling a prick, instantly flips all four limbs to scuttle off. (In Trichoplax's case, the "limbs" are cilia on every ventral cell.)

To test the mechanism, the team filled the seawater with a calcium chelator and specific channel blockers—the result: no flip, no escape. Blocking voltage-gated Ca²⁺ channels left Trichoplax insensitive; it kept crawling as if unperturbed.

These results show the trick is calcium-dependent. In short, a mechanical jolt triggers a wave of calcium in the lower cell layer, causing thousands of basal bodies to rotate almost instantaneously. The animal then resumes crawling—in the opposite direction.

Marvin Leria et al, Fast mechanosensitive and Ca²⁺-dependent reorientation of motile cilia basal bodies in the placozoan Trichoplax, Current Biology (2026). DOI: 10.1016/j.cub.2026.04.054

part 2

Comment by Dr. Krishna Kumari Challa on Saturday

How a brainless sea blob still 'feels' touch and crawls away in seconds without nerves or muscles
For a flat sea creature just a few millimeters across, a gentle poke is instantly recognized as danger. Trichoplax adhaerens—a translucent blob with no head, brain or muscles—scuttles away in seconds when touched. Imagine a flattened multicellular amoeba moving as a single unit: Trichoplax is only ~20 microns thick and a few millimeters wide. It glides on surfaces by beating tens of thousands of cilia on its lower epithelium (the underside), like microscopic oars dragging against the water.
Yet unlike most animals, Trichoplax has no obvious front or back end, no nerves or muscles at all. How can such a simple "crawling carpet" steer or change direction without a brain?

A new study reveals the remarkable flexibility of this pinhead-sized animal. While in most creatures, the orientation of each cilium is fixed early in development and locked to the body's axes, Trichoplax achieves its swift escape by reorienting its thousands of hairlike cilia.

The whole animal's direction is determined by the tiny anchors (basal bodies) that set each cilium's beat, allowing it to behave as though it "feels" the touch and flips the direction of its ciliary oars in unison.
Deep video analysis revealed that the basal bodies under Trichoplax all line up with the animal's current heading. As it crawls, there's a smooth gradient of basal-body angles from one side of the disk to the other, effectively setting the front of the animal. When Trichoplax stretches or folds its body, these gradients shift—the pattern of ciliary beat changes in step with the shape.

The new study shows that even a tiny change in body shape or mechanical stress causes the basal bodies to rotate in synchrony. This means Trichoplax steers by reorienting its oars, not by any hidden neurons. As the authors summarize, "Together, our results uncover a rapid and coordinated mechanism of BB [basal body] reorientation that links subcellular organization to whole-animal behaviour."
It wasn't obvious that a brainless blob could even detect touch. The researchers gently poked Trichoplax individuals with a fine probe and even bisected some with a microscalpel. Almost immediately—within seconds—the basal bodies swung around together. The beating cilia literally flipped direction. Each half of a cut animal suddenly crawled away from the wound.

This negative mechanotactic response (moving away from a touch) relies on basal-body rotation: as one scientist put it, "This negative mechanotactic behavior is enabled by the reorientation of BBs, which takes place across the entire lower epithelium on a timescale of seconds." One of the authors even said the lab was "jaw-on-the-floor surprised" when they first saw how quickly the cilia all pivoted around.

part1

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