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Exhaled breath can have hundreds of different compounds in it, some of which could have diagnostic potential.Credit: Getty
The chemicals found in a person’s breath might reveal the identity of the microbes in their gut. Researchers measured the levels of bacterial metabolites in the exhaled breath of mice and children and showed that they could be used to partially predict the identity and abundance of certain gut bacteria, including one species that is associated with asthma. The findings could lead to devices that help to guide treatment of conditions influenced by gut bacteria more quickly than existing methods that test stool samples.
Reference: Cell Metabolism paper
Cystatin C, a protein produced by cancer cells, could partially explain why people who have had cancer have a lower risk of Alzheimer’s disease. In a study in mice, researchers found that the protein can infiltrate the brain and bind to the molecules that make up the hallmark brain plaques of Alzheimer’s disease. This interaction draws the attention of immune cells, which then degrade the plaques. If confirmed in humans, the findings could suggest a path toward new therapies for Alzheimer’s, says cancer researcher Jeanne Mandelblatt.
Features & opinion
For decades, stimulants such as Ritalin and Adderall have been enormously useful for some people seeking treatment for their attention deficit hyperactivity disorder (ADHD). But the drugs aren’t suited to everybody — and numerous alternatives are now emerging. These include medications that work in a similar way to stimulants without being addictive, and those that change how different parts of the brain communicate. And non-pharmacological treatments — such as attention-training video games, and electrical or magnetic brain stimulation — offer tentative promise. “Our dream would be: I see the patient, I do a scan, I do a genetic test,” says Samuele Cortese, a child psychiatrist and ADHD researcher. “Given your characteristics, this is the medication, the treatment for you. We are very, very far from this.”
This article is part of Nature Outlook: ADHD, an editorially independent supplement produced with financial support from Otsuka America Pharmaceutical, Inc.
A parent explains their absence from their child’s life in The rich stopped buying yachts the year time went on sale.
Andrew Robinson’s pick of the top five science books to read this week includes an illustrated biography of Antoni van Leeuwenhoek — ‘the father of microbiology’ — and a guide to the multiverse theory for non-mathematicians.
Using a painstakingly constructed experimental set-up, researchers have managed to put clusters of around 7,000 sodium atoms into the state of ‘superposition’, in which they exist in a haze of possible locations spaced 133 nanometres apart. It’s the biggest example yet of pushing ever-larger objects into quantum states to probe the boundary between the quantum and classical worlds, explains physicist Sebastian Pedalino. “I think at the most fundamental level, the motivation for our experiments is, ‘does quantum physics that explains the physics of light and atoms also hold for larger and more complex objects, or does something new make the world look classical as things get bigger?’”
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In today’s penguin puzzle, Leif Penguinson is hiding somewhere among the lovely llamas in Bolivia’s Sajama National Park, home to the stunning chullpas (burial towers) left by the ancient Aymara people. Can you find the penguin?
The answer will be in Monday’s e-mail, all thanks to Briefing photo editor and penguin wrangler Tom Houghton.
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