Merck Antibiotic Withdrawal Raises Concerns Over Treatment Options: Merck will stop manufacturing and marketing Recarbrio in the United States, withdrawing an antibiotic combination developed for multidrug-resistant infections. The company cited a portfolio review, saying the decision was unrelated to safety or quality concerns. Approved initially in 2019, the drug treats certain complicated infections and hospital-associated pneumonia, with pediatric approval added in 2025. Experts say alternatives remain, but losing Recarbrio narrows options for difficult-to-treat Pseudomonas aeruginosa infections. The withdrawal also highlights the fragile economics of antibiotic development: stewardship appropriately limits use, reducing revenue. Some specialists question whether Recarbrio offered sufficient advantages over competing treatments. Others warn that such exits threaten future innovation, especially pediatric research, and support the proposed PASTEUR Act, which would provide fixed annual federal payments to developers of qualifying new antibiotics. (CIDRAP)

Cell Network Drives Cancer Wasting Syndrome: Researchers have identified three small cellular populations that appear to cooperate in driving cachexia, the severe muscle and fat wasting that frequently accompanies pancreatic cancer. Scientists at the University of Oklahoma used single-cell sequencing and other approaches to isolate subclusters of cancer cells, fibroblasts and macrophages within the tumor microenvironment. Rather than acting independently, the populations form a feed-forward signaling network that progressively amplifies wasting throughout the body. Disrupting individual components of this circuit in experimental models reduced cachexia-associated effects, identifying potential therapeutic targets. Published in Cell, the work is significant because cachexia can make patients too weak to tolerate chemotherapy and contributes substantially to cancer mortality. Researchers now hope to develop treatments that selectively interrupt the newly identified cellular network. (OU College of Medicine)

Sharks Hear Sounds Nearly 250 Feet Away: Wild sharks can detect and locate underwater sounds from much farther away than researchers had directly demonstrated. Scientists studying blacktip sharks off Florida used an underwater speaker to broadcast frequencies ranging from 100 to 800 hertz while drones tracked the animals from above. Sharks responded from distances reaching 74 meters, or 243 feet, frequently making abrupt turns away from the sound source. More than 70% of responses occurred in the acoustic “far field,” where researchers had been uncertain whether sharks could detect the particle motion associated with sound. The animals ignored a 10-kilohertz control signal outside their known hearing range. Published in Integrative Organismal Biology, the experiments provide rare measurements of hearing in free-swimming sharks rather than laboratory tanks and suggest sound gives the predators information about events occurring hundreds of feet away. (ScienceDaily)

Butchered Bones Track Early Chilean Hunters: Archaeologists excavating the ancient Lake Tagua Tagua basin in central Chile have uncovered new evidence that some of South America’s earliest inhabitants repeatedly hunted and butchered large mammals there roughly 12,000 to 13,000 years ago. Newly recovered bones belonging to gomphotheres—extinct elephant relatives—bear clear cut marks and were found alongside stone tools. Earlier excavations in the same basin produced extinct horse and deer bones showing cutting and burning. The assemblage is particularly valuable because animal remains, plants and artifacts have survived together, potentially allowing researchers to reconstruct how early hunter-gatherers exploited the lake environment shortly after humans reached the Southern Cone. Nearby Monte Verde dates to roughly 14,500 years ago. Researchers are now analyzing sediments and biological remains to refine the chronology and reconstruct hunting and food-processing practices. (Live Science)

Creatine Builds Lean Tissue Without Training: Creatine supplementation increased lean tissue and strength even among middle-aged adults who did not participate in a structured exercise program, according to a 12-week study. Sixty-four adults ages 45 to 65 completed the trial, receiving either 10 grams of creatine monohydrate or placebo daily while either remaining untrained or joining a resistance-and-aerobic exercise program combined with modest calorie restriction. Non-exercising participants taking creatine gained roughly 2.4 pounds of lean tissue and improved bench- and leg-press strength. Participants combining creatine with training gained nearly three pounds of lean tissue while simultaneously losing fat and showed larger strength improvements than exercising participants receiving placebo. Creatine did not produce additional aerobic-fitness gains. Published in the Journal of the International Society of Sports Nutrition, the findings add to evidence that creatine could help preserve muscle during middle age. (ScienceDaily)

Brain Disorders Leave Different Aging Signatures: A large MRI analysis suggests neurological, psychiatric and addictive disorders leave distinct patterns on the brain’s biological “aging clock.” Researchers compared structural scans from 45,900 controls with 2,698 people diagnosed with Alzheimer’s disease, mild cognitive impairment, schizophrenia, bipolar disorder, major depression, alcohol or tobacco addiction, ADHD or autism. Alzheimer’s and mild cognitive impairment showed the strongest increases in predicted brain age relative to chronological age. Psychiatric disorders were associated particularly with accelerated aging patterns in frontal and temporal regions, while addiction affected networks including the default-mode and salience systems, putamen and thalamus. ADHD and autism showed no significant overall brain-age difference. Published in PLOS Medicine, the study also connected some regional patterns with gene-expression differences. The researchers caution that the associations do not establish that these conditions actually cause accelerated brain aging. (ScienceDaily)