Researchers led by Kyle Loh demonstrate that the human brain develops as two distinct organs rather than from a single progenitor lineage. By studying gastrulation in mouse embryos, the team identified two mutually exclusive progenitor populations - Otx2-expressing cells that form the forebrain and midbrain, and Gbx2-expressing cells that form the hindbrain - each locked into fate by fundamentally different chromatin configurations. This parallel, non-branching developmental pathway overturns the long-standing model of a common early brain progenitor and explains why efforts to convert forebrain progenitors into hindbrain cells have repeatedly failed.
Using that insight, the group coaxed human pluripotent stem cells into bona fide hindbrain motor neurons that show characteristic proteins and action potentials, creating the first robust in vitro model of brainstem neurons. That advance opens experiments on diseases that selectively damage hindbrain circuits - notably spinal muscular atrophy and ALS - and on circuits that control swallowing, breathing and hunger (relevant to obesity drugs). Comparative analyses found the two-origin pattern conserved across chickens, zebrafish and even acorn worms, implying an ancient evolutionary assembly of two neural systems. Findings appear in Nature Neuroscience (Sept. 18); co-first authors are Carolyn Dundes and Rayyan Jokhai.
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GPT-6 Astra has decoded a WWI German radio cipher encrypted with the ADFGVX method, revealing a message about a British cruiser arriving at Sevastopol. The decoding involved using a specific encryption key and a detailed rearrangement process based on the key word 'TRUPPENVERSCHIEBUNG'. (prinzai.com)
Modern science is fundamentally reliant on open source software to create reproducible and testable models that improve our understanding of the universe. Open, transparent software is essential for maintaining the scientific method and advancing knowledge systematically. (jepedersen.dk)
Recent analysis challenges longstanding beliefs about the Roman road network, revealing new details about its construction and reach. The findings provide fresh insights into the infrastructure and connectivity of the ancient Roman world. (cnn.com)
Stanford Medicine researchers discovered that the human brain is actually two separate organs that evolved independently. This finding could improve understanding of neurological diseases like ALS and SMA. (med.stanford.edu)
AI analysis of over 400,000 Reddit posts uncovered reports of unexpected symptoms such as menstrual changes, chills, hot flashes, and fatigue among users of Ozempic and similar drugs. These signals, not fully documented in clinical trials, suggest areas for further medical investigation. (sciencedaily.com)
Researchers state that Europe can reduce emissions significantly without deindustrializing its economy. They emphasize that sustainable policies can balance environmental goals with industrial growth. (phys.org)
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