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Comment by Dr. Krishna Kumari Challa on March 22, 2025 at 8:47am

Scientists witness living plant cells generate cellulose and form cell walls for the first time

In a groundbreaking study on the synthesis of cellulose—a major constituent of all plant cell walls—a team of researchers have captured images of the microscopic process of cell-wall building continuously over 24 hours with living plant cells, providing critical insights that may lead to the development of more robust plants for increased food and lower-cost biofuels production.

The discovery, published in the journal Science Advances, reveals a dynamic process never seen before and may provide practical applications for everyday products derived from plants, including enhanced textiles, biofuels, biodegradable plastics, and new medical products.

The research is also expected to contribute to the fundamental knowledge while providing a new understanding of the formation of cell walls, the scientists said.

This work is the first direct visualization of how cellulose synthesizes and self-assembles into a dense fibril network on a plant cell surface.

This study also provides entirely new insights into how simple, basic physical mechanisms such as diffusion and self-organization may lead to the formation of complex cellulose networks in cells.

The microscope-generated video images show protoplasts—cells with their walls removed—of cabbage's cousin, the flowering plant Arabidopsis, chaotically sprouting filaments of cellulose fibers that gradually self-assemble into a complex network on the outer cell surface.

Hyun Huh et al, Time-resolved tracking of cellulose biosynthesis and assembly during cell wall regeneration in live Arabidopsis protoplasts, Science Advances (2025). DOI: 10.1126/sciadv.ads6312. www.science.org/doi/10.1126/sciadv.ads6312

Comment by Dr. Krishna Kumari Challa on March 21, 2025 at 11:47am

Part of the genetic risk for schizophrenia acts through the placenta, research reveals

An international research team reveals the relationship between placental DNA methylation and certain neuropsychiatric disorders.

The  has identified associations between modifications in the placenta and the risk of developing schizophrenia, bipolar disorder, and major depressive disorder.

The study was published in Nature Communications.

The study, which involved 28 researchers from 18 institutions across Europe and the United States, highlights the placenta as a key element in neuropsychiatric development. The research has demonstrated that specific epigenetic modifications in the placenta, particularly DNA methylation, can influence the expression of genes associated with psychiatric disorders. These findings suggest that genetic risk may already manifest during the prenatal stage.

Epigenetic modifications are chemical changes in DNA and its associated proteins that regulate gene activity without altering their sequence. One of the most studied modifications is DNA methylation, a process in which methyl groups—small molecules composed of one carbon and three hydrogen atoms—are added to specific regions of the DNA.

This mechanism, essential for development, environmental adaptation, and disease predisposition, is influenced by genetics and responds to factors such as diet, stress, and exposure to pollutants.

The study results indicate that schizophrenia, bipolar disorder, and major depressive disorder are the neuropsychiatric disorders most strongly linked to DNA methylation in the placenta. Other conditions, such as attention deficit hyperactivity disorder (ADHD) or autism, show some potentially causal associations, although to a lesser extent, while no visible effects were found in other analyzed pathologies.

These findings reinforce the hypothesis that schizophrenia and other disorders have a neurodevelopmental origin and that the placenta plays a fundamental role in this process.

The discovery that genetic risk may be linked to placental DNA methylation opens new avenues for preventing and treating psychiatric disorders. If we could identify risk factors at the prenatal stage, we could intervene before symptoms appear, adjusting treatments or designing personalized preventive strategies, the researchers say.

This research represents a significant advance in understanding the biological basis of neuropsychiatric disorders and opens new lines of investigation for early detection, as well as for the development of more effective therapies.

Ariadna Cilleros-Portet et al, Potentially causal associations between placental DNA methylation and schizophrenia and other neuropsychiatric disorders, Nature Communications (2025). DOI: 10.1038/s41467-025-57760-3

Comment by Dr. Krishna Kumari Challa on March 21, 2025 at 11:24am

Even Galapagos birds are exhibiting 'road rage' due to noise!

A new study has discovered that birds in the Galápagos Islands are changing their behavior due to traffic noise, with those frequently exposed to vehicles showing heightened levels of aggression.

Published in the journal Animal Behaviour the research examined the impact of vehicle noise pollution on Galápagos yellow warblers (Setophaga petechia aureola), a songbird widespread on the archipelago.

The Galápagos Islands, located over 500 miles off the coast of Ecuador, are considered a natural living laboratory due to the large number of unique, endemic species. The Galápagos yellow warbler is genetically distinct from other yellow warblers found in the Americas and is classified as a subspecies.

A visit to the Galápagos Islands in 1835 helped inspire Charles Darwin to develop the theory of evolution by natural selection. However, recent decades have seen significant human population growth. Alongside a rise in tourism, the permanent population is increasing by over 6% per year, leading to more vehicles on the islands' roads.

The new study involved researchers playing bird songs from a speaker, simulating an intruder, accompanied by recorded traffic noise at 38 locations populated by Galápagos yellow warblers on the islands of Floreana and Santa Cruz—20 sites were within 50 meters of the nearest road and 18 were over 100 meters away.

The researchers then measured song, typically used to ward off intruders, and physical, aggressive behaviors such as approaching the speaker closely and making repeated flights across it.

During trials with traffic noise, the researchers found that Galápagos yellow warblers living in roadside territories showed increased aggression, but those living away from the roads showed decreased aggression relative to trials without noise.

Importantly, the effect of living on a roadside territory was present even on Floreana Island, with only about 10 vehicles present on the island, suggesting even minimal experience of traffic affects responses to noise.

Additionally, Galápagos yellow warblers on the more populous island of Santa Cruz increased the duration of their song when confronted by traffic noise. These findings support the idea that long-term selection based on noise experience, or an individual bird's previous experience of noise, allows them to adapt and adjust the features of their songs.

Finally, the birds increased the minimum frequencies of their songs during the noise experiments, regardless of their territory's proximity to the road, helping to reduce any overlap of their songs with the low-frequency traffic noise.

The  results show that the change in aggressive responses in yellow warblers occurred mainly near roads. Birds occupying roadside territories on both islands, and therefore having regular experience of traffic noise, may have learned to increase physical aggression when the territorial intrusion was accompanied by traffic noise.

The study shows the importance of considering behavioral plasticity in conservation efforts and developing strategies to mitigate the effects of noise pollution on wildlife. It also highlights the significant impact of human activities on wildlife behavior, even in relatively remote locations such as the Galápagos Islands.

Reference: 20 March 2025, Animal Behaviour.

Comment by Dr. Krishna Kumari Challa on March 21, 2025 at 9:40am

Uniquely shaped, fast-heating nanoparticles halt ovarian tumor growth

New magnetic nanoparticles in the shape of a cube sandwiched between two pyramids represent a breakthrough for treating ovarian tumors and possibly other types of cancer, according to  researchers who developed them.

The scientists say the study underscores the importance of shape in magnetic nanoparticle design and that the findings will potentially revolutionize treatments that use heat to damage or kill cancer cells.

Made of iron oxide and doped with cobalt, the nanoparticles show exceptional heating efficiency when exposed to an alternating magnetic field. Doping refers to adding something as a means of tailoring characteristics.

When the particles accumulate in cancerous tissue after intravenous injection, they're able to quickly rise to temperatures that weaken or destroy cancer cells.

This is the first time systemically injected nanoparticles have been shown to heat tumors beyond 50° C, significantly surpassing the therapeutic threshold of 44° C for effective treatment at a clinically relevant dose.

Prem Singh et al, Precision‐Engineered Cobalt‐Doped Iron Oxide Nanoparticles: From Octahedron Seeds to Cubical Bipyramids for Enhanced Magnetic Hyperthermia, Advanced Functional Materials (2025). DOI: 10.1002/adfm.202414719

Comment by Dr. Krishna Kumari Challa on March 21, 2025 at 9:29am

Now some physicists are saying, 'the standard model is "satisfactory" but some "tensions" are emerging between observations'.

There are several different ways of measuring the expansion of the universe, including looking at the lingering radiation from after the Big Bang, exploding stars called supernovae and how gravity distorts the light of galaxies.

When the DESI team combined their new data with other measurements, they found "signs that the impact of dark energy may be weakening over time," according to a statement.
When we combine all the cosmological data, it favors that the universe's expansion was accelerating at a slightly higher rate around seven billion years ago
But for the moment there is "absolutely not certainty" about this.
Scientists are confident that "evolving dark energy" theory would be a "revolution on the level of the discovery of accelerated expansion,"
The standard cosmological model would have to be different.
The DESI research, which involved three years' worth of observations of 15 million galaxies and quasars, was presented at a conference of the American Physical Society in California.

https://summit.aps.org/events/APR-R08/1

Part 2

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Comment by Dr. Krishna Kumari Challa on March 21, 2025 at 9:21am

Dark energy seems to be changing

Dark energy, the mysterious force thought to be driving the ever-faster expansion of the universe, appears to be changing over time, according to new observations released this week.

If dark energy is in fact weakening, it would likely mean that science's understanding of how the universe works will need to be rewritten.

The new findings come from the Dark Energy Spectroscopic Instrument (DESI), which sits on a telescope at the Kitt Peak National Observatory in the U.S. state of Arizona.

What we are seeing now is deeply intriguing, say the scientists. It is exciting to think that we may be on the cusp of a major discovery about dark energy and the fundamental nature of our universe.

The DESI instrument's thin optical fibers can simultaneously observe 5,000 galaxies or quasars—blazing monsters with a black hole at their heart—for 20 minutes.

This allows scientists to calculate the age and distance of these objects, and create a map of the universe so they can detect patterns and trace its history.

Scientists have known for a century that the universe is expanding, because massive clusters of galaxies have been observed moving away from each other.

In the late 1990s, scientists shocked the field by discovering that the universe's expansion has been speeding up over time.

The name dark energy was given to the phenomenon driving this acceleration, the effects of which seem to be partially offset by ordinary matter—and an also unknown thing called dark matter.

The universe is thought to be made of 70% dark energy, 25% dark matter—and just 5% normal matter.

Science's best understanding of how the universe works, which is called the standard cosmological model, refers to dark energy as being constant—meaning it does not change.

The idea was first introduced by Albert Einstein in his theory of relativity.

Part 1

Comment by Dr. Krishna Kumari Challa on March 21, 2025 at 9:12am

Probiotic boosters shorten fever duration in pediatric trial

A clinical trial  by researchers found a probiotic mixture that significantly shortened fever duration in children with upper respiratory tract infections (URTIs). Children who received a probiotic mixture containing Bifidobacterium breve M-16V, Bifidobacterium lactis HN019, and Lactobacillus rhamnosus HN001 experienced a median fever reduction of two days compared to those given a placebo.

The research is published in the journal JAMA Network Open.

Upper respiratory tract infections are among the most common illnesses affecting young children. Reports indicate that children typically experience five to eight URTIs per year, particularly in the first five years of life. Fever is a frequent symptom and a leading cause of health care visits, often contributing to inappropriate antibiotic use. Antibiotics provide no benefit for viral infections, which account for the majority of cases.

Current symptom management through antipyretics, such as acetaminophen (paracetamol), can temporarily lower body temperature without reducing fever duration. Probiotics have shown potential in modulating immune responses, yet limited clinical evidence exists regarding their role in treating respiratory infections in children.

In the study titled "Probiotics and Fever Duration in Children With Upper Respiratory Tract Infections: A Randomized Clinical Trial," researchers conducted a triple-blind, placebo-controlled randomized clinical trial to evaluate whether a probiotic mixture could reduce fever duration in children with URTIs.

Primary outcome focused on fever duration, defined as the number of days between the first and last recorded febrile day. Secondary outcomes included antibiotic prescription rates after discharge and the incidence of antibiotic-associated diarrhea. Fever duration was recorded by caregivers, with follow-up conducted via telephone to assess compliance and adverse events.

Results indicated that children in the probiotic group experienced a significantly shorter fever duration than those in the placebo group. The median fever duration was 3 days in the probiotic group compared to 5 days in the placebo group.

Poisson regression analysis, adjusted for age, sex, and antibiotic intake, demonstrated that probiotic supplementation was associated with a fever duration risk ratio of 0.64. Adverse events, including constipation and abdominal pain, were infrequent and similar between both groups. No significant effects were observed on antibiotic prescription rates or the incidence of antibiotic-associated diarrhea, and no meaningful safety concerns were identified.

Authors acknowledge the limitations, including the single-center design and reliance on caregiver-reported temperature measurements. The trial did not distinguish between bacterial and viral URTIs, and participants may have received the probiotic at different stages of illness.

Investigators noted that while previous studies on probiotics have primarily focused on prevention rather than treatment, this trial provides evidence supporting their potential therapeutic role as an adjunct treatment for pediatric URTIs.

Silvia Bettocchi et al, Probiotics and Fever Duration in Children With Upper Respiratory Tract Infections, JAMA Network Open (2025). DOI: 10.1001/jamanetworkopen.2025.0669

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Comment by Dr. Krishna Kumari Challa on March 20, 2025 at 11:28am

Experimental antifungal compound kills multidrug-resistant fungi

The discovery of a new preclinical compound with strong antifungal activity against multidrug-resistant pathogens is described in Nature. The drug, named mandimycin, is a member of a known family of bacterial products with antifungal properties, the polyene macrolides. Unlike known compounds in this family, mandimycin binds to a novel target in the fungal cell membrane and is therefore active against a range of pathogens that are resistant to related compounds.

Mandimycin, does not bind to ergosterol in the cell membrane, the typical target of polyene macrolides. Instead, mandimycin was shown to bind various phospholipids in the fungal cell membrane. This mode of action means that it is effective against fungal pathogens that have evolved resistance to existing antifungal agents that target ergosterol, such as the clinically used agent amphotericin B.

The authors used animal models of infection to test mandimycin against a range of fungal pathogens, including multidrug-resistant Candida auris (a species listed as a priority fungal threat by the WHO), and found that the compound had increased efficacy and reduced nephrotoxicity, as compared with amphotericin B.

Zongqiang Wang, A polyene macrolide targeting phospholipids in the fungal cell membrane, Nature (2025). DOI: 10.1038/s41586-025-08678-9. www.nature.com/articles/s41586-025-08678-9

Comment by Dr. Krishna Kumari Challa on March 20, 2025 at 11:25am

Trees awaken to spring at their own pace—even within the same species in the same forest

Climatic stress events, such as extreme temperatures and prolonged droughts, are increasingly affecting tree growth and phenology—the timing of developmental stages like leaf burst and senescence.

To better understand these processes, researchers set up a long-term experiment with a permanent laser scanning station located at SMEAR II research station.

 The findings are published in the journal Agricultural and Forest Meteorology.

The scanner uses laser light to create centimeter-precise 3D models of individual trees, enabling scientists to track growth and structural changes with unprecedented detail.

Laser scanning time series enable the observation of tree changes over time without interfering with their natural growth. For the first time, scientists were able to accurately measure day-level differences in the phenology of trees in an automated manner. Subsequently, they could study the factors influencing and the effects of these phenological variations within one growth season.

The study focused on silver birch trees and found that species richness and competitive pressure for light in the immediate vicinity influenced the timing of spring leaf burst, while water availability shaped the timing of fall leaf senescence. Additionally, the timing of growth proved critical; for example, early leaf burst was linked to increased crown area growth later in the season. There was a difference of up to 12 days in the time when leaf senescence occurred in the observed trees.

This research highlights how individual trees differ in the timing and duration of their growth period due to the local growth environment, even in a relatively small and homogenous forest area. These insights, like the impact of local water availability on leaf senescence, also help us to understand how changing climate impacts tree phenology and growth within a forest stand.

The experiment provides a better understanding of how local factors drive tree growth.

Mariana Batista Campos et al, Factors and effects of inter-individual variability in silver birch phenology using dense LiDAR time-series, Agricultural and Forest Meteorology (2024). DOI: 10.1016/j.agrformet.2024.110253

Comment by Dr. Krishna Kumari Challa on March 20, 2025 at 9:09am

If helicases are nanomachines, then "ATP," or adenosine trisphosphate, is the fuel. Much like how burning gas drives the pistons of a car engine, burning ATP, the same fuel used to flex your muscles, causes the six pistons of a helicase to unwind DNA.

The study found that as ATP is consumed, it reduces physical constraints that allow the helicase to proceed along the DNA, unwinding more and more of the double strand. Thus, ATP consumption acts as a switch that increases the amount of entropy—or disorder—in the system, freeing the helicase to move along the DNA.
The helicase uses ATP not to pry DNA apart in one motion, but to cycle through conformational changes that progressively destabilize and separate the strands. ATP burning, or hydrolysis, functions like the spring in a mouse trap, snapping the helicase forward and pulling the DNA strands apart.
Among the many discoveries made by the scientists was that two helicases melt the DNA at two sites at the same time to initiate the unwinding. The chemistry of DNA is such that nanomachines move along a single DNA strand in one direction only. By binding at two sites simultaneously, the helicases coordinate so that the winding can happen in both directions with an energy efficiency unique to natural nanomachines.

 Taha Shahid et al, Structural dynamics of DNA unwinding by a replicative helicase, Nature (2025). DOI: 10.1038/s41586-025-08766-w. www.nature.com/articles/s41586-025-08766-w

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