Blood clot discovery upends consensus about how wounds heal

{"text":[[{"start":8.14,"text":"Blood clots form in a fundamentally different way from previously thought, scientists have found, in a discovery they say will have far-reaching medical implications for wound care and the treatment of clotting disorders."}],[{"start":20.48,"text":"Working at the Institut Laue-Langevin (ILL) in France, an international research team investigated the chemical reaction that triggers clotting on a wound, sealing the site and keeping it free of infection. A cylindrical blood protein called fibrinogen forms a surface layer when exposed to air — the first stage of a healing process that leads to a protective scab."}],[{"start":42.62,"text":"The consensus view has long been that fibrinogen molecules accumulate on the blood’s surface in a single, upward-tilted layer. The ILL experiments showed that in reality the protein stays flat and stacks up in multiple layers like sheets of paper."}],[{"start":58.94,"text":"Europe’s most powerful neutron source at ILL can reveal chemical structures that are beyond the reach of other analytical techniques from the way they reflect a neutron beam."}],[{"start":68.08,"text":"“It’s never easy challenging an established model of how molecules behave in nature,” said Richard Campbell of the University of Manchester, the project leader."}],[{"start":77.22,"text":"“But through using the advanced technique of neutron reflectometry, we could see the structure of these protein surfaces in more detail than scientists had seen before.”"}],[{"start":86.02,"text":"The team showed that the flat-packing behaviour is a universal feature of fibrinogen when it comes into contact with air. It may be less relevant to internal clotting deep within the body, as in deep vein thrombosis. The study is published in the Journal of the American Chemical Society."}],[{"start":null,"text":"

"}],[{"start":102.52,"text":"“It seems mind-boggling that scientists’ understanding of how fibrinogen as the main blood-clotting protein interacts with surfaces missed the underlying point of a layering mechanism,” Campbell said. Other techniques for investigating protein structures could not distinguish between the two possibilities."}],[{"start":118.66,"text":"The findings have extensive implications for healthcare, the researchers said, though they have not yet investigated the possibilities in detail."}],[{"start":126.98,"text":"They may improve the treatment of patients with blood-clotting disorders such as haemophilia or on drug-thinning medications who are susceptible to excessive bleeding. Glucose monitoring devices for diabetics would work better if clotting around the sensor could be reduced."}],[{"start":141.78,"text":"Another promising application is to improve treatment of lung disorders. In acute respiratory distress syndrome (ARDS) pulmonary inflammation leads to the leakage of fibrinogen from tiny blood vessels. The resulting clotting stops the lungs absorbing enough oxygen — often with fatal results."}],[{"start":160.66,"text":"Glenn Coope, a member of the research team at Lund University in Sweden, started studying structural data for fibrinogen while working at home during the Covid-19 pandemic. “It’s almost like we now have a full-circle moment,” he said, “as our findings may help scientists to understand better the behaviour of fibrinogen in the lungs of patients suffering from ARDS, a condition that tragically claimed so many lives during the pandemic.”"}],[{"start":186.38,"text":"Robert Jacobs, a chemistry researcher at Oxford university who was not involved in the project, said the research had interesting possible implications for our understanding of wound healing and lung function."}],[{"start":198.1,"text":"“Determining their significance will require further experiments to establish whether this multilayer organisation [of fibrinogen] persists . . . where fibrinogen is interacting with many other proteins, lipids and interfaces,” Jacobs added."}],[{"start":216.5,"text":""}]],"url":"https://audio.ftcn.net.cn/album/a_1787212556_6307.mp3"}