In the Dec. 10 SN: Star-starved galaxies, animal math, Parkinson’s roots in the gut, supersolid success, Celebrex’s controversial heart risk, a prionlike memory protein, yo-yo dieting’s downside, blue begonias and more.
GUT IMPULSE Signals from gut microbes can activate immune cells called microglia (shown here in green) in the mouse brain, causing inflammation that’s characteristic of Parkinson’s disease.
BATTERY SWAP A technique to suck a chromosome-containing structure called the spindle (white, in needle) out of a mother’s egg and place it in a donor egg emptied of its chromosomes but with healthy mitochondria can help prevent mitochondrial diseases.
Center for Embryonic Cell and Gene Therapy/OHSU
NUMBER SMARTS Cats show quantity-related abilities. Without training, cats can pick out differences between groups of a few small objects, such as 2 versus 5, but the felines may be using visual shortcuts.