Archive

Posts Tagged ‘cancer’

Nanomotors Steered Inside Living Human Cells For the First Time

March 13, 2014 1 comment

A group of researchers from Penn State have pushed the realm of possibilities for nanotechnology further as they have successfully steered a nanomotor inside of a human cell. This is the first time this feat has been accomplished. The team of chemists, biologist, and engineers was led by Tom Mallouk and has been published in Angewandte Chemie International Edition.

photo credit: Mallouk Lab/ Penn State

Nanomotors have been studied in vitro more more than a decade now. The hope is that eventually, they could be used inside of human cells for biomedical research. This nanotechnology could revolutionize drug delivery and even perform surgery in order to increase quality of life in the least invasive way possible. The earliest models were nonfunctional in biological fluid due to their fuel source. A huge breakthrough came later when the nanomotors were able to be powered externally via acoustic waves. The nanomotors used inside the human cells for the latest study were controlled by the ultrasonic waves as well as magnets.

The researchers used HeLa cells, derived from a long-lived line of cervical cancer cells, to study the nanomotors. Getting past the cell membrane was easy, as the cells ingested the nanomotors themselves. Once inside, the ultrasound was turned on and the nanomotors began to spin and move around the cell. If the signal was turned up even higher, the nanomotor can spin like a propeller, chopping up the organelles inside the cell. They were even able to puncture the cell membrane, finishing off the death sentence. Used at low powers, the nanomotor was able to move around the cell without causing any damage.

The addition of magnets gave an important advantage: steering. The motors are also able to be controlled individually, allowing the operator to take a much more targeted approach to killing diseased cells.

Ultimately, the researchers hope that one day the rocket-shaped gold nanorods will be able to move in an out of the cells without causing damage. The individual units could communicate with one another to target disease in the body, maximizing the efficacy of the treatment or even making the correct diagnosis. Working toward the goal of creating such advanced nanotechnology will not only push the boundaries of nanoengineering, but will increase our understanding of chemical and biological processes at the cellular level as well.

“The assembly of a rotating HeLa cell/gold rod aggregate at an acoustic nodal line in the xy plane. The video was taken under 500X overall magnification except for 00:23 – 00:32 and 01:16 – 01:42, where a 200X overall magnification was used.” Credit: Mallouk Lab, Penn State

“Very active gold nanorods internalized inside HeLa cells in an acoustic field. A demonstration of very active gold nanorods internalized inside HeLa cells in an acoustic field. This video was taken under 1000X magnification in the bright field, with most of the incoming light blocked at the aperture.” Credit: Mallouk Lab, Penn State

 

The above story is reprinted from materials provided by I F* Love Science.

Advertisements

Cancer Drugs Thwart Ebola In Lab

April 23, 2012 2 comments

The Ebola virus causes a hemorrhagic fever that can be deadly. (up)

Ebola is one virus you never want to catch. Ever.

After some aches and a fever, many infected people develop uncontrolled bleeding. The mortality rates from Ebola infection can run as high as 90 percent.

There’s no cure for Ebola. But a group of scientists is exploring whether some drugs already approved to treat cancer might help tame the virus.

Sounds wild. But there’s a reason — and now some evidence — to think it might work.

To reproduce, the Ebola virus needs the help of cells it invades. And a couple of cancer drugs tweak a human protein that new copies of the virus use to leave their host cells so they can infect others.

The tested drugs — Gleevec and Tasigna, both sold by Novartis — are called tyrosine kinase inhibitors. Tyrosine kinases are enzymes that put a phosphate group on a particular amino acid. Amino acids, as you might remember from high school biology, are the building blocks of proteins.

When a phosphate group gets attached to the right tyrosine block on the right protein, it changes the shape and function of the protein. And that might change everything when it comes to Ebola.

“Proteins are like little machines,” says Emory University’s Dan Kalman, one of the researchers. “As with a machine, they can be turned or turned off. The switch for turning things on or off is a modification. And one of those modifications is a phosphate group.”

In some cancers, the tyrosine kinases help trigger the uncontrolled division of cells. Gleevec and Tasigna help stop that.

When it comes to Ebola, the researchers think drugs like these could turn off a transport protein and could keep new viruses bottled up inside cells.

The Ebola lab work using collections of human cells was published in the latest issue of Science Translational Medicine. It showed that the drugs dramatically decrease the ability of Ebola to replicate. “The effect was quite pronounced,” Kalman told Shots.

And, if the theory holds, such a reduction might be enough to allow an infected person’s immune system to mop up the Ebola viruses.

“Ebola is a very nasty infection,” Kalman says. “The whole concept of containing the disease in a local group before it spreads all over the planet is something clearly we want to do.”

The next step will be to see if the drugs can make a difference in animal experiments.

Source: npr.org