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.

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.

Key driver of pancreatic cancer spread identified

A 3D tumor vessel-on-a-chip model, showing pancreatic cancer cells (green) invading an engineered blood vessel (red) by breaking down the vascular basement membrane (yellow).
Image Credit: Courtesy of Lee Lab

A Cornell-led study has revealed how a deadly form of pancreatic cancer enters the bloodstream, solving a long-standing mystery of how the disease spreads and identifying a promising target for therapy.

Pancreatic ductal adenocarcinoma is among the most lethal cancers, with fewer than 10% of patients surviving five years after diagnosis. Its microenvironment is a dense, fibrotic tissue that acts like armor around the tumor. This barrier makes drug delivery difficult and should, in theory, prevent the tumor from spreading. Yet the cancer metastasizes with striking efficiency – a paradox that has puzzled scientists.

New research published in the journal Molecular Cancer reveals that a biological receptor called ALK7 is responsible, by activating two interconnected pathways that work in tandem. One makes cancer cells more mobile through a process called epithelial-mesenchymal transition, and the other produces enzymes that physically break down the blood vessel walls.

NASA's IMAP Mission Successfully Launches to Study Our Solar System's Protective Bubble

Photo Credit: NASA / Kim Shiflett

A new era of space exploration began this morning with the successful launch of NASA's Interstellar Mapping and Acceleration Probe (IMAP) mission. The spacecraft, launched aboard a SpaceX Falcon 9 rocket from Kennedy Space Center, is on a journey to help us better understand the protective bubble surrounding our solar system, known as the heliosphere, and to improve our ability to predict space weather.

The IMAP mission is a collaborative effort led by Princeton University professor David J. McComas, with the Johns Hopkins Applied Physics Laboratory (APL) having built the spacecraft and now managing the mission operations. The spacecraft is equipped with a suite of 10 advanced instruments that will work together to sample, analyze, and map the particles streaming toward Earth from the edges of our solar system and beyond. This will provide invaluable new insights into the solar wind – the constant stream of particles from the sun – and the interstellar medium.

Visualisation of blood flow sharpens artificial heart

To be able to observe the blood flow in the artificial heart in real time, the researchers had to build a full-scale model of the human circulatory system.
Photo Credit:Emma Busk Winquist

Using magnetic cameras, researchers at Linköping University have examined blood flow in an artificial heart in real time. The results make it possible to design the heart in a way to reduce the risk of blood clots and red blood cells breakdown, a common problem in today’s artificial hearts. The study, published in Scientific Reports, was done in collaboration with the company Scandinavian Real Heart AB, which is developing an artificial heart.

“The heart is a muscle that never rests. It can never rest. The heart can beat for a hundred years without being serviced or stopping even once. But constructing a pump that can function in the same way – that’s a challenge,” says Tino Ebbers, professor of physiology at Linköping University.

Nearly 9,000 heart transplants are performed worldwide per year, and the number keeps increasing. So does the number of people queuing for a new heart, with some 2,800 on the waiting list in the EU alone, and around 3,400 in the US.

Most of the patients whose heart does not work at all are currently connected to a machine that takes care of their blood circulation for them. It is a large device, and the patient is confined to their hospital bed. For those patients, an artificial heart could be an option while waiting for a donor heart.