A large-scale metagenomic study of 2,561 gut samples from 14 mammal species on the Tibetan Plateau reconstructed 112,313 metagenome-assembled genomes representing 21,902 microbial species (86% unclassified) and identified 8,598 nonredundant antibiotic resistance genes (ARGs) spanning 28 types. The authors report 334 high-risk ARGs and seven cross-species horizontal gene transfer events involving high-risk ARGs, including three transfers between humans and nonhuman mammals. Additionally, the abundance of ARGs in human gut microbiomes on the Tibetan Plateau was greater than that in those from eastern China, Europe, and the United States, whereas the abundance of ARGs in livestock gut microbiomes from the Tibetan Plateau was lower than that in livestock gut microbiomes from those regions. This study reveals that the gut microbiota of Tibetan Plateau mammals is a largely unexplored resource and a significant reservoir of ARGs, offering crucial insights into microbiome research and demonstrating potential public health implications.

Researchers at the Mark and Mary Stevens Neuroimaging and Informatics Institute (Stevens INI) at the Keck School of Medicine of USC have developed a groundbreaking brain imaging technique that reveals how tiny blood vessels in the brain pulse with each heartbeat—changes that may hold clues to aging and diseases such as Alzheimer’s. The study, published in Nature Cardiovascular Research, introduces the first noninvasive method for measuring “microvascular volumetric pulsatility”—the rhythmic expansion and contraction of the brain’s smallest vessels—in living humans. Using ultra-high-field 7T magnetic resonance imaging (MRI), the team showed that these microvessel pulses increase with age, especially in the brain’s deep white matter, a region critical for communication between brain networks that is particularly susceptible as people age to reduced blood supply of distal arteries, the blood vessels that carry blood away from the heart and into the farthest parts of the body. Increasing microvessel pulses can disrupt systems in the brain, possibly speeding up memory loss and Alzheimer’s disease. The USC team’s innovation combines two advanced MRI approaches—vascular space occupancy (VASO) and arterial spin labeling (ASL)—to track subtle volume changes in microvessels over the cardiac cycle. The researchers confirmed that older adults show heightened microvascular pulsations in deep white matter compared to younger adults, and that hypertension further amplifies these changes.

Every new life begins after a genetic shuffle. When organisms make eggs or sperm, maternal and paternal chromosomes pair up and swap pieces of DNA in a process called crossing over. This exchange is essential: without at least one swap per chromosome pair, fertility and healthy chromosome numbers are at risk. At the same time, too many swaps—or too many DNA breaks that initiate them—can harm the genome. How do cells make sure the balance is just right? A team of researchers around Joao Matos of the Max Perutz Labs publishes the answers in Nature.

A research team led by Prof. CHU Yannan at the Hefei Institutes of Physical Science, Chinese Academy of Sciences, has uncovered a new way to detect cancer early—by analyzing the invisible chemical "scents" that the body gives off.