Nanoparticles Improve Stroke Treatment

Nanorods that spin inside the bloodstream enhance blood-clot busting drug

2 min read
Nanoparticles Improve Stroke Treatment
Image: University of Georgia

Currently there is just one drug that has been approved for treatment of acute stroke—recombinant tissue plasminogen activator, or t-PA. Essentially it works by thinning blood clots. Researchers at the University of Georgia (UGA) announced last week that they have developed a magnetic nanoparticle that when combined with t-PA can make the drug significantly more effective.

The Georgia researchers injected magnetic nanorods into the bloodstream. When stimulated by rotating magnets the nanorods act as a kind of mixing tool that shakes up blood clots that have already been thinned by t-PA.

The injected nanorods "act like stirring bars to drive t-PA to the site of the clot," said Yiping Zhao, professor of physics at UGA, in a press release. "Our preliminary results show that the breakdown of clots can be enhanced up to twofold compared to treatment with t-PA alone."

Like recent research at Penn State University in which nanorods were combined with magnets and ultrasonic waves to make them spin and thereby churn up cancer cells, the nanoparticles are referred to as nanomotors.

While this may offend the sensibility of some people’s understanding of what constitutes a motor, the term is used as well in the UGA research paper published in the journal ACS Nano.

In the research, the UGA team tested their technique on blood clots in mice. They injected a mixture of t-PA and the nanorods and then activated the nanorods with two revolving magnets once they had reached the blood stream. By triggering the spinning of the nanorods so early it helps to push the drug towards the blood clot, like fans wafting them along.

With the researchers reporting a two-fold increase to the breakdown of blood clots over just t-PA alone, the technique offers a much-needed boost to stroke treatment. While t-PA is good a thinning the blood clots, it has an unwanted side effect of thinning the blood throughout the body resulting in a real threat of hemorrhaging.

"We want to improve the efficiency of this drug, because too much of it can lead to serious bleeding problems," said Rui Cheng, a researcher on the project, in a press release. "This approach may one day allow physicians to use less of the drug, but with equal or improved effectiveness."

The next step for the researchers will be to find a nanorod material that is more biocompatible than what was used in these initial experiments. They would also like to develop a chemistry model that will connect clot dissolving speed and other parameters with the material being used.

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This CAD Program Can Design New Organisms

Genetic engineers have a powerful new tool to write and edit DNA code

11 min read
A photo showing machinery in a lab

Foundries such as the Edinburgh Genome Foundry assemble fragments of synthetic DNA and send them to labs for testing in cells.

Edinburgh Genome Foundry, University of Edinburgh

In the next decade, medical science may finally advance cures for some of the most complex diseases that plague humanity. Many diseases are caused by mutations in the human genome, which can either be inherited from our parents (such as in cystic fibrosis), or acquired during life, such as most types of cancer. For some of these conditions, medical researchers have identified the exact mutations that lead to disease; but in many more, they're still seeking answers. And without understanding the cause of a problem, it's pretty tough to find a cure.

We believe that a key enabling technology in this quest is a computer-aided design (CAD) program for genome editing, which our organization is launching this week at the Genome Project-write (GP-write) conference.

With this CAD program, medical researchers will be able to quickly design hundreds of different genomes with any combination of mutations and send the genetic code to a company that manufactures strings of DNA. Those fragments of synthesized DNA can then be sent to a foundry for assembly, and finally to a lab where the designed genomes can be tested in cells. Based on how the cells grow, researchers can use the CAD program to iterate with a new batch of redesigned genomes, sharing data for collaborative efforts. Enabling fast redesign of thousands of variants can only be achieved through automation; at that scale, researchers just might identify the combinations of mutations that are causing genetic diseases. This is the first critical R&D step toward finding cures.

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