. Scientific Frontline

Thursday, September 25, 2025

Does isolated REM sleep behavior disorder predict Parkinson’s disease or dementia?

Image Credit: Gerd Altmann

An international research team led by Université de Montréal medical professor Shady Rahayel has made a major breakthrough in predicting neurodegenerative diseases. 

Thanks to two complementary UdeM studies, scientists are now able to determine, years in advance, which individuals with a particular sleep disorder will develop Parkinson’s disease or dementia with Lewy bodies (DLB). 

The studies focus on isolated REM sleep behavior disorder (iRBD)—a condition in which people yell, thrash, or act out their dreams, sometimes violently enough to injure a bed partner. 

“It’s not just restless sleep—it’s a neurological warning sign,” said Rahayel, a neuropsychologist and researcher at the Centre for Advanced Research in Sleep Medicine at Sacré-Cœur Hospital in Montreal. 

Roughly 90 per cent of people with this sleep disorder will go on to eventually develop Parkinson’s disease or DLB. Until now, however, it was impossible to know which disease would occur—or when. 

Global ‘Noahʻs Ark’ to safeguard coral reefs, led by UH scientists

Acropora muricata, Heron Island, Australia.
Photo Credit: Claire Lager, Smithsonian

In a landmark effort to combat the devastating effects of climate change, a new global alliance with key leadership from the University of Hawaiʻi at Mānoa has been established to create a “Noahʻs Ark” for coral reefs. The initiative, detailed in a publication in BioScience, focuses on building a worldwide network of coral biorepositories to safeguard the genetic diversity of these vital ecosystems.

The research, led by Mary Hagedorn of the UH Mānoa Hawaiʻi Institute of Marine Biology and Smithsonian’s National Zoo and Conservation Biology Institute, highlights the critical need for a proactive conservation strategy. With global carbon emissions continuing to rise, the alliance aims to provide a critical safeguard against extinction by preserving coral genetic material in biosecure facilities.

Atomic Neighborhoods in Semiconductors Provide New Avenue for Designing Microelectronics

An illustration of the semiconductor material investigated for this study, which is composed of germanium with small amounts of silicon and tin. The germanium atoms are depicted as gray spheres, the silicon as red and tin as blue.
Image Credit: Minor et al/Berkeley Lab

A team led by Lawrence Berkeley National Laboratory (Berkeley Lab) and George Washington University have confirmed that atoms in semiconductors will arrange themselves in distinctive localized patterns that change the material’s electronic behavior. The research, published today in Science, may provide a foundation for designing specialized semiconductors for quantum-computing and optoelectronic devices for defense technologies.

On the atomic scale, semiconductors are crystals made of different elements arranged in repeating lattice structures. Many semiconductors are made primarily of one element with a few others added to the mix in small quantities. There aren’t enough of these trace additives to cause a repeating pattern throughout the material, but how these atoms are arranged next to their immediate neighbors has long been a mystery. Do the rare ingredients just settle randomly among the predominant atoms during material synthesis, or do the atoms have preferred arrangements, a phenomenon seen in other materials called short-range order (SRO)? Until now, no microscopy or characterization technique could zoom in close enough, and with enough clarity, to examine tiny regions of the crystal structure and directly interpret the SRO.

Study shows mucus contains molecules that block Salmonella infection

MIT researchers have discovered how mucins found in the mucus that lines the digestive tract can disarm the bacterium that causes Salmonella (purple).
Image Credit: Courtesy of the researchers
(CC BY-NC-ND 4.0)

Mucus is more than just a sticky substance: It contains a wealth of powerful molecules called mucins that help to tame microbes and prevent infection. In a new study, MIT researchers have identified mucins that defend against Salmonella and other bacteria that cause diarrhea.

The researchers now hope to mimic this defense system to create synthetic mucins that could help prevent or treat illness in soldiers or other people at risk of exposure to Salmonella. It could also help prevent “traveler’s diarrhea,” a gastrointestinal infection caused by consuming contaminated food or water.

Mucins are bottlebrush-shaped polymers made of complex sugar molecules known as glycans, which are tethered to a peptide backbone. In this study, the researchers discovered that a mucin called MUC2 turns off genes that Salmonella uses to enter and infect host cells.

Childhood concussions may trigger long-term brain changes

Researchers call for extended care and monitoring after pediatric head injuries
Image Credit: Gemini AI

A new study in mice reports that concussions sustained early in life can cause subtle brain changes that re-emerge later in life. The findings, published in Experimental Neurology, may have significant implications for understanding the long-term impact of head injuries in children.

Led by Andre Obenaus, a professor of biomedical sciences at UC Riverside’s School of Medicine, the study used advanced brain imaging techniques to identify initial signs of injury that appeared to resolve, only to return months later as more severe white matter damage.

Obenaus explained that a single concussion in early life can lead to lasting changes in white matter — the fibers in your brain that serve as communication pathways — potentially altering brain structure and function throughout an individual’s lifetime. The findings highlight the need for ongoing monitoring and care following head injuries in children, he said.

“We’ve known that white matter is vulnerable after traumatic brain injury,” Obenaus said. “What’s been missing, however, is a comprehensive, long-term look at how a single juvenile concussion affects the brain over time. Our findings fill that gap and show that brain changes from early-life concussions may not be immediately obvious, but they can reappear and worsen over time.”

Male crickets bulk up, females invest in reproductive organs

The study was done with the Gryllus vocalis species of field crickets found throughout the Southwest United States.
Photo Credit: Susan Gershman

A lab study in crickets has revealed sex differences in how the insects direct their nutritional resources to increase chances of generating offspring, finding that females prepare for producing eggs while males prioritize growing bigger bodies and banking extra energy. 

In insects that mated, the females’ investment in reproductive organs was even greater, but minimal change was seen in males – a sign that males’ reproductive success is related more strongly to winning the competition for mates, the research suggests. 

Ensuring survival while distributing finite resources is a trade-off faced by all living creatures, said first author Madison Von Deylen, a PhD candidate in the Department of Evolution, Ecology and Organismal Biology at The Ohio State University. 

“Any organism is going to face these trade-offs between allocating limited resources: Should I invest in growth? Should I build up fat stores? Or should I transition energy into some kind of reproductive output?” Von Deylen said.  

The Surprising Flexibility of Ice

Watch how the same nanoscale forces shape both ice cubes and snowflakes. PNNL researchers just recorded the first-ever molecular scale video of ice formed from liquid water over a century after this snowflake was photographed.
Image Credit: Sara Levine | Pacific Northwest National Laboratory

You’d think there’s nothing surprising left to discover about water. After all, researchers have been studying its properties for centuries. 

But today researchers at Department of Energy’s Pacific Northwest National Laboratory report a new finding. Even though ice forms in a perfectly hexagonal lattice, it is surprisingly flexible and malleable, which explains why ice so often has trapped gas bubbles. 

The findings come from the first-ever molecular-resolution observations of nanoscale samples of ice frozen from liquid water, which appear today in the journal Nature Communications.

“We observed dissolved gas not only generate cavities in ice crystals, but also migrate, merge with other gas bubbles and dissolve—behavior that is only possible due to the unusual nature of bonding in ice,” said James De Yoreo, principal investigator of the work and a Battelle Fellow at PNNL. “This work opens up an entirely new opportunity to explore ice crystallization and melting behavior at scales unimaginable only a few years ago.”

Researchers find the oldest hippopotamus ivory object in the Iberian Peninsula

The oldest hippopotamus ivory object found in the Iberian Peninsula
Photo Credit: University of Barcelona

Researchers at the Prehistoric Studies and Research Seminar (SERP) of the University of Barcelona have identified the oldest piece made of hippopotamus ivory in the Iberian Peninsula. This finding comes from the site in Bòbila Madurell (Sant Quirze del Vallès, Barcelona), dating from the second quarter of the third millennium BC, during the Copper Age.  At that time, there was no hippopotamus ivory in the Mediterranean. Therefore, this object opens up new perspectives for the study of long-distance exchange networks with the eastern shore of the Mediterranean. The discovery has been published in the Journal of Archaeological Science: Reports.

Wednesday, September 24, 2025

Astrocytes, the unexpected conductors of brain networks

 

Dozens of synapses from distinct neural circuits gather around a specialised astrocyte structure called a leaflet, which is capable of detecting and integrating the activities of multiple synapses.
Image Credit: © Lucas BENOIT et Rémi GRECO/ GIN

A collaborative study between the Universities of Lausanne (UNIL) and Geneva (UNIGE), the Grenoble Institute of Neuroscience (GIN) and the Wyss Centre for Bio and Neuroengineering reveals a previously unknown role for astrocytes in the brain's processing of information. Published in the journal Cell, their study shows that these glial cells are capable of integrating and processing signals from several neurons at once. Using cutting-edge imaging techniques, the team identified new specialised structures called leaflets, which enable astrocytes to connect several neurons, and thus neural networks. This represents a conceptual shift in our understanding of the brain.

The brain does not function via neurons alone. In fact, nearly half of the cells that make up the brain are glial cells, and among them, astrocytes occupy a special place. Their name comes from their star-shaped skeleton, but their external appearance is more reminiscent of certain nebular stars, with an irregular, filamentary contour that allows them to insert themselves into the smallest gaps between neurons, blood vessels, and other cells. They are thus in close contact with synapses, the communication hubs between neurons.

Early changes during brain development may hold the key to autism and schizophrenia

Photo Credit: Michal Jarmoluk

Researchers at the University of Exeter have created a detailed temporal map of chemical changes to DNA through development and aging of the human brain, offering new insights into how conditions such as autism and schizophrenia may arise.

The team studied epigenetic changes – chemical tags on our DNA that control how genes are switched on or off. These changes are crucial in regulating the expression of genes, guiding brain cells to develop and specialize correctly.

One important mechanism, called DNA methylation, was examined in nearly 1,000 donated human brains, spanning life from just six weeks after conception through to 108 years of age. The researchers focused on the cortex, a region of the brain involved in high-level functions such as thought, memory, perception, and behavior. Correct development of the cortex during early life is important to support healthy brain function after birth.

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