Sheep Wool Gets Into Bone Repair
Who knew sheep wool might have a future in bone repair? Researchers at King’s College London and collaborating institutions tested keratin-based membranes as an alternative to collagen for guided bone regeneration, first with human bone marrow stromal cells and then in 42 male rats with 6-mm critical-size calvarial defects. All keratin membranes supported cell viability, while mineralized M-Ker5TE1 and highly crosslinked Ker5H3 showed particularly strong metabolic activity and osteogenic gene expression. Ker5 films also kept fibroblasts largely at the surface, suggesting an effective barrier against soft-tissue cell infiltration. After 8 weeks, collagen produced the greatest overall bone volume at 29.13 mm³, compared with 17.73 mm³ for Ker5, the best-performing keratin formulation by bone volume. But Ker5 had its own party trick: histology showed defect bridging, lamellar-like bone, Haversian-like canals, and more spatially organized collagen architecture than the collagen control. No signs of inflammation were observed after keratin implantation. The findings remain preclinical, with degradation, mechanical performance, and immune responses still needing investigation. Still, wool entering its orthopedic era was not on our bingo card.
Source: Biomaterials Advances
Cannabis Has a Heartbeat Twist
Cannabis may have just thrown cardiology a curveball. In the randomized crossover MARY-JANE trial, investigators at the University of California, San Francisco, tracked 108 habitual cannabis users without known arrhythmias (mean age, 32 years; 59% women) over 14 days, randomly assigning cannabis inhalation or abstinence each day. Across 713 cannabis days and 616 abstinence days, inhaled cannabis was associated with 9% fewer ectopic beats overall, driven by a 10% reduction in premature atrial contractions; premature ventricular contractions did not show any significant change. Each cannabis inhalation was also associated with a 2% reduction in ectopic beats. Meanwhile, step counts, sleep duration, and glucose levels were also unchanged. But before anyone adds cannabis to the arrhythmia toolkit, adherence was imperfect, participants were habitual users, and withdrawal and cointervention effects may have influenced the results, limiting causal interpretation. Turns out the trial brought fewer extra beats—but there are still plenty of questions.
Source: JACC
Houston, We Have a Gut Problem
Space travel may look glamorous, but the gut microbiome apparently has its own mission agenda. Researchers analyzed 488 plasma samples from 52 astronauts—11 women and 41 men—before, during, and after 2- to 9-month International Space Station missions and found approximately 40 compounds altered during spaceflight. Several gut microbial products of protein fermentation, including p-cresol sulfate, phenylacetylglutamine, 4-ethylphenol sulfate, phenol sulfate, and 3-indoxyl sulfate, increased after launch. The pattern suggested microgravity may slow intestinal transit, allowing microbes to burn through available carbohydrates and increasingly ferment protein instead. That matters because protein fermentation can generate potentially unfavorable compounds, including ammonia and hydrogen sulfide, while some metabolites identified here have previously been associated with cellular senescence, mitochondrial dysfunction, and other health effects. Plasma uric acid also dropped approximately 10% during flight, while caffeine and fish-related metabolites declined; diet-related exposures accounted for only 27.5% of changing features. Most metabolic shifts subsided within days after landing, with few sex-specific differences. Researchers suggested boosting slowly fermented carbohydrates, including fiber, on longer missions to help curb protein fermentation. Apparently, even in zero gravity, your gut still expects you to eat your vegetables.
Source: Nature Communications
Can Tea Brew a Better Mood?
Tea may have a little more brewing beneath the surface than its usual caffeine credentials suggest. In a cross-sectional analysis published in Nutrients, researchers at Kaohsiung Medical University examined 27,119 Taiwan Biobank participants, including 1,122 (4.1%) who reported a lifetime history of depression. Habitual tea drinking was associated with a lower prevalence of self-reported depression after adjustment for demographic, lifestyle, and cardiometabolic factors. The apparent sweet spot was 1 to 2 cups daily (350-700 mL), particularly semi-fermented teas such as oolong and nonfermented varieties such as green or white tea. Fully fermented black tea showed no significant association, nor did three or more cups daily, weekly, or monthly tea drinking. Polyphenols and L-theanine could be working behind the scenes, but no biomarkers were measured to test that theory. The cross-sectional design, single self-reported depression question, possible reverse causation, and missing information on sleep, diet, and socioeconomic status also kept causality firmly out of reach. So, no steeping prescriptions for now anyway.
Source: Nutrients
The intersection of medicine and the unexpected reminds us how wild, weird, and wonderful science can be. The world of health care continues to surprise and astonish.
