Science Odds and Ends

By harnessing the body's blood-clotting system, researchers have designed nanoparticles that scout out tumours and then call in a second type of nanoparticle to deliver cancer-killing drugs.

Sangeeta Bhatia, a bioengineer at the Massachusetts Institute of Technology in Cambridge, and her colleagues found that using the two nanoparticles in tandem in mice increased the amount of drug delivered to a tumour by 40-fold relative to controls. Tumours in these mice stopped growing, whereas those in mice that received only one type of nanoparticle did not.

Bhatia's team was inspired by the ability of the body's clotting system to mount a huge response at an injured site. A clot forms thanks to a cascade of reactions that leads to the cross-linking of a large amount of a protein called fibrin.

The researchers designed their nanoparticles to piggyback on this cascade. "We use the body's natural amplification processes to get more drug to the target," says Bhatia. The study is published in Nature Materials.

Mayo Clinic researchers and collaborators from the UK have apparently cured mice with well-established prostate tumors with no visible side effects via a new kind of tumor vaccine. And if it works for men like it worked for mice, it could make prostate cancer a preventable condition and open the door to additional cancer vaccines.

The findings are preliminary but promising. Geneticists basically assembled a complementary DNA library from healthy prostate tissue and inserted snippets of that genetic code into a swarm of viruses that were introduced to the mice intravenously. This cDNA causes the viruses to produce prostate antigens, basically sending the immune system a distress signal with the prostate’s unique signature on it.

One of the reasons the body often can’t beat cancerous growths on its own is because it can’t see the tumor cells very well, so the immune system doesn’t know where to fight its battles even as the cancer takes more ground. But those engineered viruses expressing those prostate antigens--antigens are like molecular tags indicative of a specific infection, allergen, pathogen, etc.--basically raise the visibility of the problem at the prostate.

This causes the mice’s own body to mount a serious T-cell assault on the prostate and anything foreign that might be hiding out there. So the body basically thinks it’s being invaded by viruses expressing these cancer related antigens, but it doesn’t really matter what the immune system thinks. When the dust settles, the immune system has pounded the prostate with defensive measures, eradicating the tumor cells there.

There have been instances in Earth history when average temperatures have changed rapidly, as much as 10 degrees Celsius (18 degrees Fahrenheit) over a few decades, and some have speculated the same could happen again as the atmosphere becomes overloaded with carbon dioxide.

New research lends support to evidence from numerous recent studies that suggest abrupt climate change appears to be the result of alterations in ocean circulation uniquely associated with ice ages.

"There might be other mechanisms by which greenhouse gases may cause an abrupt climate change, but we know of no such mechanism from the geological record," said David Battisti, a University of Washington atmospheric sciences professor.

Battisti noted that while carbon dioxide-induced climate change is unlikely to be abrupt, the impacts of changing climate could be.

The research is published online June 19 by Nature Geoscience.

TPP wrote:

Science Chic wrote: Those are SWEET!

Just like me


Did ya both check out the other pictures?

Viruses make up "about 8 or 9 percent" of our genome, says science journalist Carl Zimmer. Startlingly, human childbirth would not be possible without a viral mutation.