Category Archives: Medical Nanotech

Through the use of microscopic, perhaps even molecular-scale nanomachines, we will be able to affect the human body in an extremely localized and precise way, virtually eliminating side-effects of treatment and sending treatment success rate soaring.

Cafe Scientifique: 2007-03-17

Cafe Scientifique Poster for 2007-03-17So I made it to Cafe Scientifique again this month. I’m two for two since I started going; here’s hoping I make it to more.

The topic this month was “Nature vs Nurture Revisited: New research is changing the age-old debate.” The expert panel was Robert Gerlai, Ph.D (Dept. of psychology, UofT) and Christopher E. Pearson, Ph.D (Dept. of genetics and genome biology, SickKids Research Institute). I expected there to be more talk about specific issues of NvN, like sexual orientation or intelligence. Instead, the talk mostly dealt (as far as I saw) with the biological mechanisms that come into play.

IANAEB, but in a nutshell there are two processes being discussed here: Darwinian evolution and Lamarckian evolution1. Darwinian evolution is of course the process by which a gene or group of genes that produces a phenotype conducive to its own propagation will tend to be better represented in the gene pool, beating out its allele rivals. Lamarckian evolution is the theory that an organism can pass on traits it has acquired during its own lifetime.

Sounds weird, right? Our DNA sequence is fixed — how could we possibly pass on genes we weren’t born with? Well, it turns out that cytosine (the “C” in GATTACA) can be methylated or de-methylated by the introduction of certain substances, and that this new form can have different phenotypic effects. This process is referred to as epigenetics. So what happens is, someone eats a diet2 containing a substance that toggles the methylation state of a certain sequence in some of their cells, including germ cells. It doesn’t affect them, or not much, because they have already developed into a human. However, the new methylation state is persistent. So when one of those germ cells becomes another person, there is a chance that the altered sequence will trigger some aberrant effect.

This has all sorts of implications, some good and some bad. On the one hand, we might find that certain diseases are caused or exacerbated by a certain methylated state on a certain gene, and that simply making sure that the population gets a certain amount of some nutrient will reduce the incidence of that disease. On the other hand, this may increase the amount of medicating that we do. Drug companies and “alternative medicine” manufacturers may jump on the band wagon, marketing products that claim to “de-methylate your cancer genes” or whatever, playing on people’s ignorance and fear to get them to eat more pills. What’s more, there may be even more pressure than there already is on women to treat their bodies like baby machines and to make sure that even before they start thinking about reproducing they maintain a diet that will produce the optimal methylation state in their bodies.

Just as with any new technology or discovery, the recent findings in epigenetics contain potential for a lot of good and a lot of evil. The talk today was very informative, and I’m grateful to the two panelists for taking the time to make it out. Today I learned about a facet of evolution that I would never have imagined existed.

1 Note that these are not competing theories, although they could be seen as competing processes. Like Darwinian evolution, Lamarckian evolution has been observed and measured, though it is more difficult to reproduce and control than Darwinian evolution for various reasons.

2 This could also be the result of other environmental influences, such as atmosphere composition, but diet seems the most effective since we actually have in-built mechanism for distributing food’s components around our bodies.

Organizing neural networks

An israeli group is raising the bar for people working with artificial neural networks. Yael Hanein of Tel Aviv University and her team have construed a way to get neuron clusterss to arrange themselves in neat patterns on a sheet of quartz, by using 100-μm-thick bundles of — you guessed it — nanotubes. This greatly increases the efficiency and lifespan of these neuron clusters, and is the first step toward sophisticated biosensors, neuronal grafting and — as one of the commentors on the New Scientist article said — “Cylons that behave like mice”.

Blood-Powered Implants

A common impediment to effective powered implantation is the issue of powering it. While power requirements may be made very low, and small batteries made very efficient, that may not be good enough for a posthuman intending to live with a prosthetic potentially for the next couple of hundred years. And a battery is one more element that can break down, not to mention that they are usually filled with toxic substances. So what is more elegant than a fuel cell that draws power from one’s own blood? As IOL reports, some Japanese researchers have come up with a little device that generates power from the glucose in blood, using only substances already naturally occurring in the body to catalyze the reaction.

Capsule Endoscope

Imagine this: You have some sort of ulcer or infection or something in your lower intestine. Although it is difficult to figure out exactly what’s wrong without expensive and invasive surgery, your doctor makes an educated guess and prescribes some medication for it. The drug is in a fairly high dose because by the time it reaches the affected area much of it has leached into other areas of your digestive tract. There are some uncomfortable side-effects, but eventually you feel better.

Now imagine your doctor could give you a small device the shape and size of a largish pill. You swallow it, and your doctor controls it wirelessly, leading it through your stomach and intestines. The device transmits video of the affected area and grabs a small sample of fluid for analysis. You pass the capsule easily, and the doctor figures out from the fluid exactly what’s wrong. An identical capsule goes back down the hatch, makes its way to the affected area and deposits a small amount of medication directly to the area that needs it. Your side-effects are greatly reduced or none, your recovery is faster, and there is less chance of misdiagnosis. Best of all, your hospital bill is way smaller than if you had had to go under the knife.
Endoscope capsule by Olympus Medical Systems Corporation

News Release

The Human Brain Produces Morphine

According to a story on Wired, the human brain is capable of producing morphine, given the right stimuli.

Scientists have debated this for a while; earlier studies finding trace amounts of morphine in human and animal tissue were attributed by many to the consumption of foods containing the chemical or to other factors. Now, some folks at Germany’s Martin-Luther-University Halle-Wittenberg have proof that the brain produces its own morphine.

So why is this exciting? Well, for one thing, it means that administering morphine to someone for medical purposes may get a whole lot easier and safer. Instead of morphine, the patient could be administered a “morphine precursor” which would prompt the body to dope itself. Even more fundamental, it means we have a new way to look at how morphine affects the brain in the first place.

This study has many other applications. It may open doors to the reasons that zombies eat brains, enabling us to develop better weapons to destroy them and other walking dead. It doubtless will spur advances in addiction treatment, suggesting that some people who are especially susceptible to morphine addiction may just have a natural morphine deficiency.

In a nutshell, this paper looks like it will change the way we see pain treatment, addiction and the undead forever.