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Sometimes less is more: Messier nanoparticles may actually deliver drugs more effectively than tightly packed ones

The tiny fatty capsules that deliver COVID-19 mRNA vaccines into billions of arms may work better when they’re a little disorganized. That’s the surprising finding from researchers who developed a new way to examine these drug-delivery vehicles one particle at a time—revealing that cramming in more medicine doesn’t always mean better results.

The research was presented at the 70th Biophysical Society Annual Meeting, held in San Francisco from February 21–25, 2026.

Lipid nanoparticles, or LNPs, are microscopic bubbles of fat that can ferry fragile RNA molecules into cells. They were crucial to the success of mRNA vaccines, and scientists are now working to use them to deliver treatments for cancer, genetic diseases, and other conditions. But there’s a problem: only about 1% to 5% of the cargo inside LNPs actually gets released inside cells.

What a zinc gradient in dentin could mean for fillings and tooth health

Teeth are composites of mineral and protein, with a bulk of bony dentin that is highly porous. This structure allows teeth to be both strong and sensitive. Besides calcium and phosphate, teeth contain trace elements such as zinc. Using complementary microscopy imaging techniques, a team from Charité Berlin, TU Berlin and HZB has quantified the distribution of natural zinc along and across teeth in 3 dimensions. The team found that, as porosity in dentin increases towards the pulp, zinc concentration increases 5~10 fold. These results help to understand the influence of widely-used zinc-containing biomaterials (e.g. filling) and could inspire improvements in dental medicine.

The paper is published in the journal VIEW.

Teeth have a complex structure: the dental pulp with the nerves is surrounded by dentin, a porous bony material, covered externally by enamel in the mouth and cementum in the roots. Although dentin is criss-crossed by countless micrometer-sized dentin tubules, teeth can withstand decades of cyclic, repeated forces. The density of the dentinal tubules increases towards the pulp, meaning that the dentin becomes increasingly porous towards the inside.

Will probiotics work for you? Models map gut metabolism to predict success

A new study demonstrates that computer models of gut metabolism can predict which probiotics will successfully establish themselves in a person’s gut and how different prebiotics affect production of health-promoting short-chain fatty acids. The findings are published in PLOS Biology by Sean Gibbons of the Institute for Systems Biology, US, and colleagues.

Probiotic and prebiotic supplements show highly variable results across individuals, making it difficult to predict who will benefit from these interventions. This variability comes from complex interactions between introduced probiotics, each person’s existing gut microbiota, and their diet.

In the new work, researchers first tested a metabolic model on data from two previous studies in which participants diagnosed with type 2 diabetes were given a placebo or probiotic/prebiotic mixture designed to improve glucose control and healthy participants were given a placebo or a probiotic treatment designed to treat recurrent Clostridioides difficile infections, respectively.

Chemistry-powered ‘breathing’ membrane opens and closes tiny pores on its own

Ion channels are narrow passageways that play a pivotal role in many biological processes. To model how ions move through these tight spaces, pores need to be fabricated at very small length scales. The narrowest regions of ion channels can be just a few angstroms wide, about the size of individual atoms, making reproducible and precise fabrication a major challenge in modern nanotechnology.

In a study published in Nature Communications, researchers at The University of Osaka have addressed this challenge by using a miniature electrochemical reactor to create ultra-small pores approaching subnanometer dimensions.

In biological cells, ions flow in and out through channels in cell membranes. This ion flow is the basis for generating electrical signals, such as nerve impulses that trigger muscle contraction. The channels themselves are made of proteins and can have angstrom-wide narrow regions. Conformational changes of these proteins in response to external stimuli open and close the channels.

MIT physicists improve the precision of atomic clocks

Every time you check the time on your phone, make an online transaction, or use a navigation app, you are depending on the precision of atomic clocks.

An atomic clock keeps time by relying on the “ticks” of atoms as they naturally oscillate at rock-steady frequencies. Today’s atomic clocks operate by tracking cesium atoms, which tick over 10 billion times per second. Each of those ticks is precisely tracked using lasers that oscillate in sync, at microwave frequencies.

Scientists are developing next-generation atomic clocks that rely on even faster-ticking atoms such as ytterbium, which can be tracked with lasers at higher, optical frequencies. If they can be kept stable, optical atomic clocks could track even finer intervals of time, up to 100 trillion times per second.

Advances and Integrations of Computer-Assisted Planning,… : Operative Neurosurgery

ONSNew ONSReview Advances and Integrations of Computer-Assisted Planning, Artificial Intelligence, and Predictive Modeling Tools for Laser Interstitial Thermal Therapy in Neurosurgical Oncology by Warman et al Johns Hopkins Medicine Congress of Neurological Surgeons (CNS) Isaac Yang.


E to surrounding healthy tissue, LiTT offers promising therapeutic outcomes for both newly diagnosed and recurrent tumors. However, challenges such as postprocedural edema, unpredictable heat diffusion near blood vessels and ventricles in real time underscore the need for improved planning and monitoring. Incorporating artificial intelligence (AI) presents a viable solution to many of these obstacles. AI has already demonstrated effectiveness in optimizing surgical trajectories, predicting seizure-free outcomes in epilepsy cases, and generating heat distribution maps to guide real-time ablation. This technology could be similarly deployed in neurosurgical oncology to identify patients most likely to benefit from LiTT, refine trajectory planning, and predict tissue-specific heat responses.

Why chronic pain lasts longer in women: Immune cells offer clues

Chronic pain lasts longer for women than men, and new research suggests differences in hormone-regulated immune cells, called monocytes, may help explain why.

In a new paper in Science Immunology, researchers at Michigan State University found a subset of monocytes release a molecule to switch off pain. These cells are more active in males due to higher levels of sex hormones such as testosterone, the team found.

Females, however, experienced longer-lasting pain and delayed recovery, because their monocytes were less active. Geoffroy Laumet, MSU associate professor of physiology, and Jaewon Sim, a former graduate student in his lab, discovered the same pattern in both mouse models and human patients.

Polyamine metabolism as a regulator of cellular and organismal aging

Polyamines — putrescine, spermidine, and spermine — are ubiquitous cationic molecules that are essential for cellular proliferation and homeostasis. Their intracellular concentrations decline with age, contributing to physiological and cognitive deterioration. Recent studies have revealed that spermidine supplementation extends lifespan and improves cognitive and cardiac function in various model organisms, suggesting that maintaining polyamine balance has anti-aging potential. Polyamine metabolism is tightly regulated through biosynthesis, degradation, and transport; however, age-associated upregulation of spermine oxidase (SMOX) and accumulation of its toxic byproduct acrolein promote oxidative damage and cellular senescence. Suppressing SMOX activity or polyamine degradation attenuates senescence markers and DNA damage, highlighting spermine catabolism as a therapeutic target. Polyamines also modulate epigenetic regulation, including DNA methylation and histone acetylation, thereby influencing gene expression and chromatin structure during aging. Moreover, polyamine-dependent hypusination of eIF5A sustains protein synthesis in senescent cells. These multifaceted actions indicate that polyamine metabolism integrates redox control, translational regulation, epigenetic maintenance and autophagy to determine cellular and organismal longevity. While animal studies demonstrate clear anti-aging effects of spermidine and spermine, human clinical evidence remains limited, with variable outcomes likely due to bioavailability and metabolic conversion. Future strategies combining dietary or probiotic polyamine enhancement, enzyme-targeted inhibitors, and personalized metabolic interventions hold promise for extending healthspan. Collectively, maintaining optimal polyamine homeostasis emerges as a key approach to counteract aging and age-related diseases.

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