The week’s most astounding developments from the neobiological frontier.

September 15, 2022

Neurodegenerative diseases triggered by hospital infections

Hospital-acquired infections are a major U.S. health concern—really one of the worst. Over a million of them occur every year, they claim tens of thousands of American lives, and they cost the health care system billions and billions of dollars. But are those costs just the tip of the iceberg? Using the Swedish National Patient Register, researchers at the Karolinska Institute in Stockholm analyzed nearly 300,000 cases of Alzheimer’s disease and more than 100,000 cases of Parkinson’s disease diagnosed from 1970–2016. Having a hospital-acquired infection five or more years earlier, they found, increased the risk of these neurodegenerative diseases. The highest risk was for people whose infections occurred before they were 40. Their chances of Alzheimer’s more than doubled, and they had a more than 40 percent increased risk of Parkinson’s. So we ask the obvious: If hospital acquired infections trigger some systemic processes that lead to neurodegenerative disease, how do we counter them? PLOS Medicine

Deep network hallucination and protein design

Researchers at the University of Washington in Seattle are describing in a pair of papers this week how they used a deep-learning approach to design new proteins, nanoparticles, and molecular oligos. In one paper, they used what they call “deep network hallucination” to design cyclic protein assemblies. In the other paper they used another technique to design protein backbones. “Our results highlight the rich diversity of new protein structures that can be generated using deep learning, and pave the way for the design of increasingly complex components for nanomachines and biomaterials,” they write. Science

Population-level impact of genetic risk factors on healthy life years lost

Another big hit for biobanks. Researchers at the University of Helsinki in Finland analyzed genetic information from 735,748 people in FinnGen, a public-private partnership of Finnish biobanks and government health records, and in the UK Biobank. They looked at the impact of genetic risk factors on a standard measure of human suffering known as disability-adjusted life years (DALYs)—you can think of a DALY as one year of healthy life lost. Considering 80 different diseases, they ranked more than 1,000 genetic risk factors in terms of their health impact and compared them to traditional modifiable risk factors, like dietary sodium intake. Knowing for the first time the relative contribution of different genetic risk factors on disease burden at the population level, the authors write, could help prioritize targets for gene therapy trials and give scientists new ways to evaluate medical interventions across generations. Nature Medicine

The growing specter of blue-spectrum light

Scientists at the University of Exeter in Cornwall, United Kingdom, have taken images captured on SLR cameras by astronauts on the International Space Station from 2012–2013 and 2014–2020 to map how the spectral composition of lighting across Europe has changed. The analysis shows a widespread shift from high-pressure sodium street lights at night to white LED lighting with increased blue spectrum emissions. The researchers explored how that relates to the suppression of melatonin production in humans, the visibility of stars from the ground, and the impact of the new lights on insects and bats and found that it is widely increasing the risk of harmful effects to humans and animal ecosystems in Europe. Science Advances

Controversy erupts over dinosaur extinction

What killed the dinosaurs? It’s a question that has fascinated everyone from scientists to little kids everywhere since the days of Darwin. They went from dominating just about every terrestrial niche to complete extinction, and what drove them away is an evolutionary whodunnit of mammoth proportions (not wooly mammoths—those came later and may yet return). For years, the leading theory has been that the dinosaurs were done in by a long, severe climate shock caused by a huge asteroid or comet that smashed into Mexico’s Yucatán peninsula some 66 million years ago. Now researchers at Dartmouth, Princeton, and the University of California, Berkeley, are reigniting the debate over an alternative theory. They argue the cause of extinction was actually something known as “large igneous provinces,” which are continental voluminous volcanic eruptions. The volcanoes, they suggest, were the real culprit. They spilled thousands of square kilometers of mafic magma onto the land, dumped massive amounts of gasses into the atmosphere, and choked the great lizards to extinction. PNAS