By Lynne Friedmann
For decades researchers have worked to develop nanoparticles that deliver cancer drugs directly to tumors, minimizing the toxic side effects of chemotherapy. Even with the best of these nanoparticles, however, only about 1 percent of the drug typically reaches its intended target.
Now, a team of researchers from MIT, the Sanford-Burnham Medical Research Institute, and UCSD have designed a new type of delivery system in which a first wave of nanoparticles homes in on the tumor then calls in a much larger second wave of nanoparticles that dispenses the cancer drug. This communication between nanoparticles, enabled by the body’s own biochemistry, was found to boost drug delivery to tumors by over 40-fold in a mouse study.
The findings appear in Nature Materials. News release at
A new class of stellar explosion
The Palomar Transient Factory survey, currently taking place at Palomar Observatory, is a real-time search for explosions of stars, known as supernovae. It involves multiple telescopes and a distant computing center that examines new images moments after they are taken. High-speed data transfer provided by the High Performance Wireless Research and Education Network (HPWREN) is essential to the survey. Based at the San Diego Supercomputer Center on the UCSD campus, the HPWREN network includes backbone nodes, typically on mountaintops, to connect often hard-to-reach areas in remote environments.
To date, the Palomar survey has discovered more than 1,000 supernovae, including four unusual ones that are among the most luminous in the cosmos. These new kinds of supernovae could help researchers better understand star formation, distant galaxies, and what the early universe might have been like. News release at (
How blood clots form
Scientists at The Scripps Research Institute (TSRI) have discovered new elements of the blood clot-formation process. The findings help to establish a new model of clot formation.
According to the old model, an injury to the wall of blood vessels causes smooth muscle cells to expose a clot-organizing protein called tissue factor. Now scientists believe that tissue factor exists both on the surfaces of these smooth muscles as well as on circulating immune cells, but in an inactive state.
In the TSRI study researchers showed that a cell-surface receptor (P2X7), which is known to promote inflammation when stimulated, also plays a major role in the clot-forming process by activating tissue factor.
To confirm this, the team bred mice that lacked functional P2X7 receptors and found that these P2X7-knockout mice failed to form stable arterial blood clots when the vessel wall was exposed to a clot-inducing substance. Importantly, these mice did not suffer from uncontrollable bleeding as a result of their inability to form stable arterial blood clots. This finding suggests that new clot-preventing drugs targeting the P2X7 pathway might not have this unacceptable side effect.
The findings appear in the Journal of Clinical Investigation. News release at
Lynne Friedmann is a science writer based in Solana Beach.