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Surgeons at Xijing Hospital in Xi’an, China, performed the first transplantation of a non-human liver into a human body.Credit: Xijing Hospital, Air Force Medical University in Xi’an China
Surgeons in China say they have transplanted a pig liver into a person’s body for the first time. With consent from the man’s family, the clinically dead patient received a liver from a pig that was genetically modified to prevent the recipient from rejecting the pig organ. The surgeons say the pig liver secreted more than 30 millilitres of bile every day, and the colour and texture of the liver remained normal after 10 days. In January, a US team conducted a similar experiment with a pig’s liver located outside a person’s body, and there have been further experiments with genetically modified pig kidneys and hearts.
Read more: Experts weigh in on the issues surrounding the xenotransplantation of pig organs in Nature Medicine (11 min read, from 2022)
Stellar detectives have identified seven stars that recently gobbled up a rocky planet. The planets seem to have been eaten during their stars’ relatively stable main-sequence period. If this is true, it means these systems have continued to be chaotic long after their formation, with planets disintegrating or falling into their star, says astronomer Johanna Teske. “It’s an inference at this point. We need to look at these systems in more detail.”
A slew of studies have identified how inflammation in the brains of people with COVID-19 might explain neurological symptoms such as loss of smell, headaches and memory problems. Growing evidence suggests that the immune response triggered by the virus leads indirectly to brain inflammation. One study found that people with long COVID and ‘brain fog’ had a leakier blood-brain barrier, which might let in molecules that cause inflammation.
Reference: Nature Neuroscience paper
Indian biotechnology company ImmunoACT is producing a much cheaper version of a cancer treatment known as chimeric antigen receptor (CAR) T-cell therapy. A single treatment of NexCAR19 costs between US$30,000 and $40,000 — a tenth of the price of comparable products now available. The safety profile also appears to be better than some US-approved CAR-T products. NexCAR19 is now being used to treat blood cancers in hospitals across India. “These are people for whom all other treatments have failed,” says immunologist Alka Dwivedi.
For 15 years, geoscientists have been involved in a complicated technical process to determine whether human impacts on Earth amount to a new geological epoch: the Anthropocene. This week, following a controversial vote and challenge, the final verdict has arrived from the International Union of Geological Sciences: we are not in a new epoch. The current lack of agreement on a start date should not detract from the Anthropocene as a concept, says a Nature editorial. The reality is that humans are leaving a discernible fingerprint on Earth systems.
Nature | 5 min read & Nature editorial | 5 min read
Features & opinion
AI image generators can amplify biased stereotypes in their output. There have been attempts to quash the problem by manual fine-tuning (which can have unintended consequences, for example generating diverse but historically inaccurate images) and by increasing the amount of training data. “People often claim that scale cancels out noise,” says cognitive scientist Abeba Birhane. “In fact, the good and the bad don’t balance out.” The most important step to understanding how these biases arise and how to avoid them is transparency, researchers say. “If a lot of the data sets are not open source, we don’t even know what problems exist,” says Birhane.
Invasive ant species such as the Argentine ant (Linepithema humile) have conquered the land so thoroughly that “it can seem as if the spread of global trade was an Argentine ant plot for world domination”, writes science journalist John Whitfield. He explores what makes these insects so successful, their effects on ecosystems and the temptation to compare their spread with humanity’s own power struggles. Ants “speak to life’s ability to escape our grasp, regardless of how we might try to order and exploit the world”, writes Whitfield. “There’s something hopeful about that, for the planet, if not for us.”