Tiny motors controlled inside human cell

Nanomotors exist in nature too, like this example from the tail of a bacter

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Science of Materials

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For the first time, scientists have placed tiny motors inside living human cells and steered them magnetically.

The advance represents another step towards molecular machines that can be used, for example, to release drugs into specific locations within the body.
There is interest in the approach because it could enhance the benefits of drugs while minimising side effects.
The rocket-shaped metal particles were propelled using ultrasound pulses.
Materials scientist Prof Tom Mallouk, from Penn State University, and colleagues have published their research in the journal Angewandte Chemie International Edition.
"As these nanomotors move around and bump into structures inside the cells, the live cells show internal mechanical responses that no one has seen before," said Prof Mallouk.
"This research is a vivid demonstration that it may be possible to use synthetic nanomotors to study cell biology in new ways."

This microscope image of a cell shows some of the gold-ruthenium nanomotors

Up until now, nanomotors have been studied only "in vitro" - in laboratory apparatus - but not in living human cells.
At low ultrasonic power, the nanomotors had little effect on these cells. But when the power was increased, the nanomotors surged into action, zooming around and bumping into organelles - structures within the cell that perform specific functions.

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One dream application of ours is Fantastic Voyage-style medicine”

Prof Tom Mallouk Penn State

The nanomotors could be used as "egg beaters" to essentially homogenise the cell's contents, or act as battering rams to puncture the cell membrane.

"We might be able to use nanomotors to treat cancer and other diseases by mechanically manipulating cells from the inside," said Prof Mallouk.
In addition, he said: "Nanomotors could perform intracellular surgery and deliver drugs non-invasively to living tissues."
The researchers were able to steer the tiny motors with magnetic forces.
The scientists also found that the nanomotors could move autonomously - independently of one another - an ability that is important for future applications.
Destructive forces "Autonomous motion might help nanomotors selectively destroy the cells that engulf them," Prof Mallouk explained.
"If you want these motors to seek out and destroy cancer cells, for example, it's better to have them move independently. You don't want a whole mass of them going in one direction."
Describing the potential uses of nanomotor technology, the Penn State professor invoked a 1966 science fiction film in which a submarine and its human crew are miniaturised and injected into the blood-stream of a dying man in order to save him.
"One dream application of ours is Fantastic Voyage-style medicine, where nanomotors would cruise around inside the body, communicating with each other and performing various kinds of diagnoses and therapy.
"There are lots of applications for controlling particles on this small scale."
The idea of molecular-scale surgery can be traced back to a lecture by celebrated physicist Richard Feynman in 1959 called "There is plenty of room at the bottom".
In the talk to the American Physical Society (APS), he explained: "Although it is a very wild idea, it would be interesting in surgery if you could swallow the surgeon.
"You put the mechanical surgeon inside the blood vessel and it goes into the heart and 'looks' around. It finds out which valve is the faulty one and takes a little knife and slices it out."

SOURCES: http://www.bbc.co.uk/news/science-environment-26136979

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Chikungunya Fever may soon Spread to the US.

Health experts are concerned that chikungunya fever — a debilitating mosquito-borne disease that was once confined to Africa and Asia — has now spread to the Caribbean and may soon begin to make its way across North and South America.

An infection with the chikungunya (chik-un-GUN-ya) virus causes severe pain, high fever, headache, nausea, vomiting and rash. The name is derived from an East African word for "that which bends," a reference to the posture adopted by infected people who are stooped over from severe joint pain. 

And though the disease can't be spread directly from person to person, a mosquito that bites a person who's infected with the virus can easily spread the disease by biting another person, according to the Centers for Disease Control and Prevention (CDC). [7 Devastating Infectious Diseases]

The spread of chikungunya was first reported by the World Health Organization (WHO) in December 2013, after 10 residents on the Caribbean island of St. Martin were confirmed to have the disease.

In the months since then, chikungunya has spread to other Caribbean countries, including popular tourist destinations such as Guadeloupe, Martinique and the British Virgin Islands.

Will chikungunya spread to the US?

The disease isn't unknown in the United States, but all previous documented cases have been in people who traveled outside the United States to countries where chikungunya is established, and were not caused by infected mosquitos within the United States.

That may change, however, since the mosquitos that carry the virus — Aedes aegypti and Aedes albopictus — are already found in the United States. Some experts worry that it's only a matter of time before chikungunya fever spreads to the United States.

"We definitely should be concerned," said Laura Harrington, a professor of entomology at Cornell University who specializes in the spread of chikungunya and other tropical diseases.

The death rate from chikungunya is fairly low — about 1 to 2 percent — "but it does cause a lot of discomfort," Harrington told Live Science. Most of the deaths caused by the disease are among the elderly or people with compromised immune systems.

And because the virus has an incubation period of from two to 12 days, according to the CDC, people carrying the disease often won't know they have it.

Climate change and chikungunya

Another factor contributing to the spread of chikungunya is the gradual warming of the Earth resulting from climate change. "I think it can play a really important role," Harrington said.

She notes that some of the hallmarks of climate change — specifically, an increase in rainfall and an increase in average temperature — make perfect conditions for the spread of the two mosquitos that can carry the chikungunya virus.

A. albopictus, commonly known as the Asian tiger mosquito, is now well-established in the southern United States, having arrived in the mid-1980s. And as the climate warms, "it's gradually moving northward," Harrington said — the mosquito is already found as far north as New York City.

Stopping the spread

To combat the spread of chikungunya and other mosquito-borne diseases, experts recommend practical measures such as eliminating standing bodies of water (where mosquitos often breed) under potted plants and in spare tires, using mosquito nets, wearing long-sleeved shirts and long pants, and applying mosquito repellents.

These tips are especially important for people who already have the infection, since a mosquito can spread the disease to another person through its bite.

If there's any upside to the pain and misery of a chikungunya infection, which only rarely lasts more than a week, it's this: Once a person is exposed to the virus, the body is protected from reinfection for a lifetime, scientists say.

SOURCES http://news.yahoo.com/chikungunya-fever-virus-spread-us-140307803.html

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