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Feld and his colleagues have been able to image live, untreated cells by using an optical technique based on interferometry: a laser beam passed through a sample is compared with a reference beam of similar wavelength that is not passed through the cell. For example, it takes longer for light to travel through a cell than through, say, water. Researchers can measure that time delay, or phase shift, and then can map the cell and its motions on the scale of nanometers.

Broadband light from a superluminescent diode (superluminescent diode (SLD) (EG&G, Gaithersburg, MD), output power 3 mW, center wavelength 845 nm, full width half-maximal bandwidth 22 nm...

The second harmonic of the cw Nd:YAG laser (CrytaLaser, special custom-built module; wavelength 532nm, 500 mW) is used as an illumination source for a typical inverted microscope (Axiovert 100, Carl Zeiss).

Note: I think the main link in this thread has incorrectly summarized the article. I just read the original article and the headline is just plain wrong IMO.

As a neuroscientist, I find this article interesting and food for thought, but not earth-shattering as the summary seems to imply. As a person, though, it underscores the unsettling reality that we really have little to no understanding of how and why anesthetics actually work, which I guess is why they call it practicing medicine.

the summary is incorrect and TFA is total rubbish. Go read the original paper. Here is the abstract:
Abstract
It is known that the action of general anesthetics is proportional to their partition coefficient in lipid membranes (Meyer-Overton rule). This solubility is, however, directly related to the depression of the temperature of the melting transition found close to body temperature in biomembranes. We propose a thermodynamic extension of the Meyer-Overton rule which is based on free energy changes in the system and thus automatically incorporates the effects of melting point depression. This model accounts for the pressure reversal of anesthesia in a quantitative manner. Further, it explains why inflammation and the addition of divalent cations reduce the effectiveness of anesthesia.

http://www.biophysj.org/cgi/rapidpdf/biophysj.106. 099754v1?maxtoshow=&HITS=10&hits=10&RESULTFORMAT=& author1=Heimburg&searchid=1&FIRSTINDEX=0&resourcet ype=HWCIT/

The article is not about sound waves but about the mechanism of action of anesthetics and the proposal is that the action is not via drug binding to specific receptors but due to their affect on the thermodynamic properties of the membrane. In fact, since anesthetics screw up transmission (be that electrical or whatever) by altering membrane properties nothing can be concluded about the nature of the mechanism that they disrupt. It would be an identical situation to say that since salt can melt ice then hockey players glide over the ice not because of force applied but to the amount of pickles they eat (or smth like that).

Slashdot becoming f.....g drudge report.

As a neuroscientist

Because all of that is explained by their model, as outlined in their first and second articles.

In short, it goes like this: by dissolving in the membrane, anesthetics lower the melting point of the membrane, thereby affecting its sound propagation properties. The lowering of the melting-point can be reversed by applying pressure, lowering temperature, or by lowering pH. So by assuming that the nerve impulse is transmitted by a soliton in the membrane, everything is explained.

Here's the actual article
http://www.biophysj.org/cgi/rapidpdf/biophysj.106. 099754v1.pdf

They build upon Meyer & Overton's work & specificly say that Hodgkin-Huxley is not satisfactory with relation to anestethics.

My question is: Does the Meyer-Overton rule mean that elephant tranquilizers are 10,000 more times soluble than morphine?

On further review, it seems that the CBC article is total crap, but that the original paper isn't that far off the deep end. I admit that I don't know enough to really follow or critique the research, but it doesn't seem to be the crackpot theory that TFA implies. Nowhere, for example, does that paper say that nerves don't use electricity. In fact, the paper refers to "solitons" as a piezo-electric effect. They are merely proposing a new mechanism on top of previous theories, not trying to completely throw out all neuroscience to date.

To recap: Completely bogus headline, based on a completely bogus bit of popular science reporting, which itself is based on a possibly intriguing (but tentative) bit of original research. Nothing to see here.

This is all a bit old hat, isn't it?
I was pushing bloodcells around using dielectrophoresis in Uni over a decade ago. Shortly thereafter, water was being tested for purity using the same method, and one of the post-docs was moving tagged proteins around too.
How come it took so long to create a system to be used in protein manufacture?
examples:
http://ieeexplore.ieee.org/xpl/abs_free.jsp?arNumb er=297897 (1994)
http://www.biophysj.org/cgi/content/abstract/77/1/ 516 (1994)
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd= Retrieve&db=PubMed&list_uids=9351287&dopt=Citation (1997)

Wow, and I thought my background in circadian research would never be useful!

A proposed schematic of the Drosophila's circadian system is illustrated here. In the associated paper, we basically created a mathematical model of the schematic using standard biochemical equations and harnessed the power of computers to test the model against results from actual "wet-lab" experiments.

Wow, and I thought my background in circadian research would never be useful!

A proposed schematic of the Drosophila's circadian system is illustrated here. In the associated paper, we basically created a mathematical model of the schematic using standard biochemical equations and harnessed the power of computers to test the model against results from actual "wet-lab" experiments.

Being spanish, I feel extra proud of the media attention is getting this case study. Hopefully, the spanish politicians will now consider to promote more spanish science.

Although the author has said this should be taken as a definitive treatment, it opens the doors to further research and clinical trials. Don't expect a full treatment procedure before two years, but this was a pretty good start.

The original article published by Dr. Brú in 1998 is freely available from the journal of Biophysics. For those of who enjoy maths.

"Lead Poisoning is the most common environmentally caused disease in the United States, affecting 4-5% of children nationwide."
link

"Lead poisoning is the leading environmentally induced illness in children. At greatest risk are children under the age of six because they are undergoing rapid neurological and physical development."
link

"New research suggests that millions more children than previously thought might have lead-linked mental impairment, while another study supports a strong link between lead exposure and juvenile delinquency."
link

"Lead is a highly toxic metal that was used for many years in products found in and around our homes. Lead may cause a range of health effects, from behavioral problems and learning disabilities, to seizures and death."
link

... and these are just some quotes from google results.

For what it's worth, the idea that came to him in 2001 is called Atomic Force Sensing, and is actually about five years older than that. The only difference is that Gimzewski is looking at spontaneous oscillations rather than driven oscillations - and that's where the difficulty lies, because it's very, very hard to show that those oscillations are due to activity of the cells and not, say, vibrations caused by a truck driving by outside. I'm skeptical that these oscillations are coming from the cells (as you can tell from my other posts in response to this article), but if they are, it suggests a very, very interesting mechanism that we know nothing about.