Axios

A strong defense system allows what the brain needs in and keeps out toxins and pathogens. It's a vital function that also stops promising drugs from reaching their target (think: a tumor) and prevents neuroscientists from probing how the brain works. Scientists at Caltech have now engineered viruses that can bypass this barrier in mice and deliver genes to many different types of cells.

Why it matters: In the past few decades, a wealth of tools have been created to study the brain — neurons can be individually labeled and imaged, genes can conceivably be edited, and the brain's cells can be manipulated with light in order to see what effect it has on functions like memory. But that all hinges on getting into the brain. This new work opens up the brain's intricacies for unprecedented study and possibly treatment of neural disorders (like Parkinson's and Huntington's diseases), brain cancers, and Friedreich's ataxia and other peripheral nervous system diseases.

Pharmaceutical company Endo International is removing Opana, a powerful painkiller, from the market. Endo's decision comes a month after Scott Gottlieb, commissioner of the Food and Drug Administration, pressured Endo to pull Opana off the market in light of the widespread opioid crisis that has led to record deaths.

The removal will cost Endo a one-time charge of $20 million, the company said Thursday. Opana brought in $159 million in sales for Endo last year.

In the wake of the dangerous opioid epidemic that is currently plaguing the United States, some doctors have decided to forgo prescribing opioids and are instead turning to long-established drugs like Novocain and ibuprofen to perform surgeries, Bloomberg reports. They're also increasingly advising patients to seek massage and mediation treatments to supplement pain medication.

"Opioids are being shunned," said Lynn Webster, an anesthesiologist and vice president at PRA Health Sciences Inc. "Physicians are avoiding prescribing them for fear of losing their licenses."

Their reasoning: Drug overdoses are now the leading cause of death among Americans under 50, and the numbers are expected to worsen in 2017, according to the NY Times. Meanwhile, doctors are still writing hundreds of millions opioid prescriptions every year. This leaves doctors vulnerable to malpractice and other criminal charges. The alternative drug push is key to protecting doctors from losing their licenses, and patients from getting hooked.

Scientists have taken detailed images of one of the proteins involved in Alzheimers Disease for the first time, which may help researchers create treatments for the disease.

Alzheimers is characterized by a buildup of two proteins, tau proteins inside of neurons and amyloid plaques on the outside. Healthy tau proteins look sort of like fiber-optic cables that help support neurons. But sometimes, those proteins become tangled, and the tangles can build up and warp the neuron's shape, rendering them useless.

Why it matters: Tau tangles have been implicated in a number of neuro-degenerative diseases, including Alzheimer's, Huntington's and Parkinson's Disease. These detailed images allow scientists to parse apart the molecular structure of the tangles, which could help them understand why the tangles happen, how they spread, and possibly even develop drugs to treat them.