Category Health/Medical

Mice were exposed to two auditory fear conditioning, separated by five hours. Both memories were encoded by shared neurons in the lateral amygdala while they were encoded by different neurons in the auditory cortex. Mice showed freezing behavior in response to 7kHz and 2kHz tones. Induction of optical long term depotentiation (LTD) to synapses specific to 7kHz fear memory, erased only that memory (test 3) without affecting the other memory (test 4) that was stored in shared neuron ensemble.
Credit: Kaoru Inokuchi, Kareem Abdou

Memories are formed through long-term changes in synaptic efficacy, a process known as synaptic plasticity, and are stored in the brain in specific neuronal ensembles called engram cells, which are activated during corresponding events...

Wen Zhou et al. Structure of the Human cGAS–DNA Complex Reveals Enhanced Control of Immune Surveillance. Cell, 2018 DOI: 10.1016/j.cell.2018.06.026

Scientists have defined the structure and key features of a human immune-surveillance protein that guards against cancer and bacterial and viral infections. The identification of two human-specific variations in the protein closes a critical knowledge gap in immunology and cancer biology.

The human body is built for survival. Each one of its cells is closely guarded by a set of immune proteins armed with nearly foolproof radars that detect foreign or damaged DNA...

Fresh oranges. Credit: © Nitr / Fotolia

A new study has shown that people who regularly eat oranges are less likely to develop macular degeneration than people who do not eat oranges. Researchers at the Westmead Institute for Medical Research interviewed more than 2,000 Australian adults aged over 50 and followed them over a 15-year period.

The research showed that people who ate at least one serving of oranges every day had more than a 60% reduced risk of developing late macular degeneration 15 years later. Lead Researcher Associate Professor Bamini Gopinath from the University of Sydney said the data showed that 3flavonoids in oranges appear to help prevent against the eye disease...

Nanoparticles releasing microRNAs (light blue) inside a human brain cancer cell. Credit: Yuan Rui, Johns Hopkins

In a “proof of concept” study, scientists at Johns Hopkins Medicine say they have successfully delivered nano-size packets of genetic code called microRNAs to treat human brain tumors implanted in mice. The contents of the super-small containers were designed to target cancer stem cells, a kind of cellular “seed” that produces countless progeny and is a relentless barrier to ridding the brain of malignant cells.

Results of their experiments were published online June 21 in Nano Letters. “Brain cancer is one of the most widely understood cancers in terms of its genetic makeup, but we have yet to develop a good treatment for it,” says John Laterra, M.D., Ph.D...