DNA Methylation: Reversible Gene Expression in Cancer and Development

DNA methylation is one way that gene expression is controlled. In a previous post I discussed the use of hypomethylating drugs to de-methylate tumor suppressor genes, thus reactivating them, as a good way to treat cancer.

DNA methylation is involved from the very beginning of human embryonic development. In early development (fertilisation to 8-cell stage), the eukaryotic genome is demethylated. From the 8-cell stage to the morula, de novo methylation of the genome occurs, modifying and adding epigenetic information to the genome. By blastula stage, the methylation is complete. This process is referred to as "epigenetic reprogramming".

This newsrelease discusses new findings in DNA methylation--how methylation can be thought of more as a dimmer switch, and less as an on-off switch.

A gene is like a long sentence that describes the structure of a protein. The letters in the sentence are spelled out in the building blocks of the DNA strand of which the gene is part.

Like a sentence, a gene has a well-defined starting point, called the start site. Unlike a sentence, a gene has a second region that runs to the left of the start site. That region is known as the promoter, and this is the off-and-on switch for the gene.

DNA methylation involves chemical changes that take place in the promoter region. These changes alter the gene so that it cannot be turned on. Usually, these chemical changes occur in areas of the promoter that are close to the start site, and that’s where others have looked for them in the C/EBPa gene.

Plass and his colleagues, however, looked two to three times farther from the start site than usual.

“We were surprised to find that methylation had occurred along this region far upstream from the start site,” Plass says.

DNA methylation is very complex, and central to both animal development, and gene expression of the mature animal. Methylation can shut down oncogenes--preventing cancer--and methylation can shut down tumor suppressor genes--allowing cancer to progress. The B-vitamin Folic Acid is intimately involved in DNA methylation, and this article provides useful background to the critical role of folate in both preventing and promoting cancers.

DNA methylation falls into the category of epigenetics. Epigenetic regulation of gene expression can largely determine the difference between a chimpanzee and a human.

Perhaps mastering epigenetics will reduce the need for vectored gene therapy, at least in the short run.

Stalking the Stealthy Atom

Have you ever stood in a long line at airport security, thinking to yourself, "there has got to be a better way?" We all understand the need for caution. A pressurised aluminum shell at 12,000 meters cannot take very much stress before it disintegrates, spilling its precious cargo across the countryside--that means you. Finding the explosives before the explosives find you, becomes very important to a frequent flyer. That is one application of cavity ring-down spectroscopy--a type of laser absoption spectroscopy. Cavity ring-down spectroscopy is an excellent way of detecting materials, but it is limited to measuring a narrow spectrum of 1 nm at a time.

A recent breakthrough described in this newsrelease allows the simultaneous scanning of wavelengths spanning 100 nm (750-850nm)--from the visible into the near infra-red.

Described in the March 17 issue of Science,* the new technology is an adaptation of a conventional technique, cavity ring-down spectroscopy, for identifying chemicals based on their interactions with light. The JILA system uses an ultrafast laser-based "optical frequency comb" as both the light source and as a ruler for precisely measuring the many different colors of light after the interactions. The technology offers a novel combination of a broad range of frequencies (or bandwidth), high sensitivity, precision and speed. A provisional patent application has been filed.

...."What a frequency comb can do beautifully is offer a powerful combination of broad spectral range and fine resolution," says NIST Fellow Jun Ye, who led the work described in the paper. "The amount of information gathered with this approach was previously unimaginable. It's like being able to see every single tree of an entire forest. This is something that could have tremendous industrial and commercial value."

Frequency combs are an emerging technology designed and used at JILA, NIST and other laboratories for frequency metrology and optical atomic clocks, and are being demonstrated in additional applications. NIST/JILA physicist John (Jan) Hall shared the 2005 Nobel Prize in physics in part for his contributions to the development of frequency combs [www.nist.gov/public_affairs/newsfromnist_frequency_combs.htm]. In the application described in Science, the frequency comb is used to precisely measure and identify the light absorption signatures of many different atoms and molecules.

The JILA system described in Science offers exceptional performance for all four of the primary characteristics desired in a cutting-edge spectroscopic system:

* The system currently spans 125,000 frequency components of light, or 100 nanometers (750-850 nm) in the visible and near-infrared wavelength range, enabling scientists to observe all the energy levels of a variety of different atoms and molecules simultaneously.

* High resolution or precision allows scientists to separate and identify signals that are very brief or close together, such as individual rotations out of hundreds of thousands in a water molecule. The resolution can be tweaked to reach below the limit set by the thermal motion of gaseous atoms or molecules at room temperature.

* High sensitivity--currently 1 molecule out of 100 million--enables the detection of trace amounts of chemicals or weak signals. With additional work, the JILA team foresees building a portable tool providing detection capability at the 1 part per billion level. Such a device might be used, for example, to analyze a patient's breath to monitor diseases such as renal failure and cystic fibrosis.

* A fast data-acquisition time of about 1 millisecond per 15 nm of bandwidth enables scientists to observe what happens under changing environmental conditions, and to study molecular vibrations, chemical reactions and other dynamics.

By comparison, conventional cavity ring-down spectroscopy offers comparable sensitivity but a narrow bandwidth of about 1 nanometer. A more sensitive "optical nose" technique developed at NIST can identify one molecule among 1 trillion others, but can analyze only one frequency of light at a time. Other methods, such as Fourier transform infrared spectroscopy, provide large bandwidths and high speed but are not sensitive enough to detect trace gases.

In a previous posting I discussed the use of mass spectrometry for similar purposes. Both techniques have their advantages, and each will find niches of opportunity.

It is important that we be able to sense the world around us in very fine detail, given the potential dangers we face in our lives and travels. As we delve more deeply in the worlds of bio-engineering and nanotechnology, the need for more sensitive detection instruments becomes even more acute.

G Makes the World Go Round

Hat tip to Kevin at Intelligence Testing (IQ Corner) for linking to this exceptional review article by CF Chabris on the cognitive and neurobiological underpinnings of "g", general intelligence. The article came to Kevin via GNXP blog. Here are links to other articles by Chabris.

The timing of Kevin's posting was fortuitous for me, as I am currently reading the book Behavioral Genetics in the Postgenomic Era by Plomin et al, which contains several chapters on related topics. I enjoy reading about topics that interest me from the perspective of several disciplines simultaneously, if possible.

For those new to the topic, I recommend reading this introduction by Linda Gottfredson first, then the review article above. Here is a gentle introduction to the genetic basis of intelligence which takes a very evenhanded approach to the nature-nurture debate. This is a discussion of intelligence as it may relate to human similar or human equivalent machine intelligence, and other non-human intelligence, from the viewpoint of a singularitarian at the Singularity Institute. The author takes the viewpoint that a machine intelligence will be the first "superintelligence" that humans encounter. He discusses the possible fallout from that encounter. Here is the Singinst.org description of levels of organization of general intelligence.

If the mean IQ in the developed world were ten points lower, it would not be the developed world that we know. Hospitals would be far more primitive, scientific research would be at a very retarded stage in comparison with modern science, there would not be enough intelligent engineers and technicians to maintain our complex technologies. G makes the world go around.

Robots Just Don't Get Any Respect

Have you ever wondered why there are conspiracy tales about black helicopters, and virtually none at all about robots? Humans tell jokes about robots. It is a question of being taken seriously. Everyone knows that helicopters are capable of swooping down just about anywhere on earth and carrying people away. But robots are tied down to a power cord. Robots have no mobility, and are slow and clunky besides.

The University of Texas at Dallas wants to change all that. Last year, UTD won a $750,000 grant to develop artificial muscles that run on chemical fuel, rather than electricity. Now, UTD is announcing the development of working artificial muscles that can run on alcohol and hydrogen. Robots powered by such muscles could carry their own fuel with them, and be mobile like a person.

The new muscles simultaneously function as fuel cells and muscles, according to Baughman, corresponding author of the Science article. A catalyst-containing carbon nanotube electrode is used in one described muscle type as a fuel cell electrode to convert chemical energy to electrical energy, as a supercapacitor electrode to store this electrical energy and as a muscle electrode to transform this electrical energy to mechanical energy. Fuel-powered charge injection in a carbon nanotube electrode produces the dimensional changes needed for actuation due to a combination of quantum mechanical and electrostatic effects present on the nanoscale, Baughman said.

In another of the described artificial muscles – currently the most powerful type – the chemical energy in the fuel is converted to heat by a catalytic reaction of a mixture of fuel and oxygen in the air. The resulting temperature increase in this “shorted fuel-cell muscle” causes contraction of a shape memory metal muscle wire that supports this catalyst. Subsequent cooling completes the work cycle by causing expansion of the muscle.

“The shorted fuel cell muscles are especially easy to deploy in robotic devices, since they comprise commercially available shape memory wires that are coated with a nanoparticle catalyst. The major challenges have been in attaching the catalyst to the shape memory wire to provide long muscle lifetimes, and in controlling muscle actuation rate and stroke,” said Baughman. “Students and scientists of all ages will be working on optimizing and deploying our artificial muscles, from high school students in our NanoExplorer program to retired technologists in our NanoInventor program.”

Read the full report here.

These artificial muscles are linear actuators, like animal muscle. Linear actuators better enable the type of motion that humans are capable of, including swimming, climbing, running, jumping, lifting, and carrying. It is easy to imagine robo-cops, robo-firefighters, robo-soldiers, robo-miners, and robo-construction workers, all built with this type of artificial muscle. Of course, having the ability to carry its own fuel gives this type of robot staying power, and respect.

Here is a good source of information about artificial muscles, from the University of New Mexico. Registration to view the videos is free, and the research papers are available without registration.

Here is a website for a commercial enterprise developing artificial muscles, a spinoff of SRI International.

This is a NASA website discussing some fascinating applications of artificial muscle. It contains videos, a video lecture, and articles, images, and links for artificial muscle information.

The UTD muscle that runs on chemical fuel is the type of breakthrough needed to create mobile robots. If a robot can run on alcohol, why not sugar, protein, or fat? The convergence of robotics, artificial intelligence, and advanced nano-chemo-energetics promises to bring about robots with the potential to be truly fearsome.

We humans need to become smarter, or robots will be telling human jokes soon.

Update: Be sure to check out Chris Chatham's post on military robots at Develintel Blog. If that does not make you a bit uneasy, check your body temperature to see if it is above ambient level.

Beta Amyloid and Alzheimer's: What it Does, How to Stop it

Beta Amyloid protein, Abeta, is involved in neuron damage in several diseases, including Alzheimer's. A recent report from Johns Hopkins has solidly established the association between Beta Amyloid and memory loss in a mouse model of Alzheimer's.

A research team that included members from The Johns Hopkins University and the University of Minnesota Medical School has for the first time identified a substance in the brain that is proven to cause memory loss. This identification gives drug developers a target for creating drugs to treat memory loss in patients with dementia.

....The researchers hypothesized that there was a substance in the brain that causes memory decline that is present even before nerve cells begin to die. To test that hypothesis, the team used mice whose genetic makeup was manipulated to develop memory loss much in a way people develop subtle memory problems before the earliest stages of Alzheimer's disease. Using mice that showed early signs of memory loss and had no plaques or nerve cell loss in the brain, they discovered a form of the amyloid-beta protein that is distinct from plaques. They extracted and purified this newly found protein complex and injected it into healthy rats. The rats suffered cognitive impairment, confirming that this protein has a detrimental effect on memory.

Read the full report here.

We learn even more about beta amyloid, and how it kills brain cells in alzheimer's, from this research report from Children's Hospital and Recearch Center, Oakland.

In a study published in the February 28th issue of the Proceedings of the National Academy of Sciences, lead scientist Hani Atamna, Ph.D., found that alterations in the production of heme (a molecule that contains iron) may be the key to understanding why excessive amyloid-beta is toxic to brain cells. Dr. Atamna had previously discovered that Alzheimer's patients have abnormal amounts of heme in their brains. In new research results, Atamna's team showed that amyloid-beta readily binds with heme to form a compound that can be flushed from cells. When there is insufficient heme or too much amyloid-beta, however, the amyloid-beta forms large toxic "clumps" that the cell cannot dissolve and eliminate.

Though heme binding with amyloid-beta can be beneficial, if too much heme is bound up with amyloid-beta, there may be insufficient heme available for the cell to properly function. When this happens, the cell's mitochondria, which are the tiny structures inside brain cells that produce the energy the cells need to function, begin to decay. Dr. Atamna refers to this phenomenon as a "functional heme deficiency" because the cells are still forming heme, but it is trapped within an amyloid-beta/heme compound.

When they examined the heme/ amyloid-beta compound researchers in the Atamna laboratory were surprised to discover it was a peroxidase--a type of enzyme that reacts harmfully with biological materials essential for proper brain function such as serotonin and L-DOPA. Dr. Atamna believes that the combination of functional heme deficiency, which harms mitochondria needed to produce energy, together with the increase in oxidative damage caused by the peroxidase, is what eventually kills the cell.

So we can see that beta amyloid first causes confusion and memory loss, then it binds heme and triggers oxidative damage to neurons, and mitochondrial dysfunction leading to apoptosis of the neuron. Now we need to look at ways to prevent and arrest those processes before the damage is irrevocable.

In this research report, we learn how researchers used Herpes Simplex Virus (HSV) as a vector for gene therapy, to inhibit amyloid beta production and accumulation.

We generated replication-defective herpes simplex virus (HSV) vectors that inhibit Abeta accumulation, both in vitro and in vivo. In cell culture, HSV vectors expressing either (i) short hairpin RNA directed to the APP transcript (HSV-APP/shRNA), or (ii) neprilysin, an endopeptidase that degrades Abeta (HSV-neprilysin), substantially inhibited accumulation of Abeta. To determine whether these vectors showed similar activity in vivo, we developed a novel mouse model, in which overexpression of a mutant form of APP in the hippocampus, using a lentiviral vector (LV-APP(Sw)), resulted in rapid Abeta accumulation. Co-inoculation of LV-APP(Sw) with each of the HSV vectors showed that either HSV-APP/shRNA or HSV-neprilysin inhibited Abeta accumulation in this model, whereas an HSV control vector did not. These studies demonstrate the utility of HSV vectors for reducing Abeta accumulation in the brain, thus providing useful tools to clarify the role of Abeta in AD that may facilitate the development of novel therapies for this important disease.Gene Therapy advance online publication, 16 March 2006

Read more here.

There is a great deal more involved with Alzheimer's than what is discussed in these three articles. You may be wondering where the beta amyloid protein came from in the first place. This useful review article will help to answer that question, and discusses several present and future treatments for Alzheimer's as well. It may take an hour or two to read and digest, but while doing so, be thankful you have that capacity.

There are many, many unanswered questions remaining. But since Alzheimer's is considered a priority by most western governments, well designed research that addresses those questions is very likely to be funded.

The Seven Deadly 'Xins of Botulinum

Clostridium Botulinum is a bacterium that produces seven deadly toxins, A through G. These toxins block the neuromuscular junction and cause paralysis of muscles. The botulinum toxin A, or BoTox, can either kill or heal. When used as a biological weapon, the toxin is deadly. When used to treat pain, it can be a godsend.

This newsrelease details how scientists from UW Madison, and the University of Texas, have determined exactly how the deadly botulinum toxin A can gain entry into neurons to block their function.

Writing in the current online edition of Science, a team of researchers at the University of Wisconsin-Madison and the University of Texas report that botox latches onto a protein known as SV2 to gain entry into neurons.

"Our work shows that botox is really smart and clever," says senior author Edwin Chapman, a UW-Madison professor of physiology and an investigator of the Howard Hughes Medical Institute. "It uses SV2 to sneak into nerves like a Trojan horse."

"Botulinum neurotoxins are among the six most dangerous bioterrorism threats," adds lead author Min Dong, a UW-Madison postdoctoral researcher in the department of physiology. "Knowing the protein receptor for [botulinum toxins] can pave the way for developing anti-toxin reagents which may block the entry of toxins into cells."

The botulinum toxins, of which there are seven types, are made by a bacterium commonly found in soil, known as Clostridium botulinum. Of the seven-identified by the letters A through G--botox A lasts a particularly long time in neurons. While that feature makes it especially useful in the clinic, it also means that botox A may pose a particularly dangerous threat as a biological weapon.

The toxin enters neurons by binding to nerve endings and preventing the release of crucial chemical messengers, known as neurotransmitters, that communicate with muscles. When enough nerve endings are invaded, botox can lead to paralysis and death. ....

Chapman and his team located the exact molecular gateway through which botox penetrates cells by gathering clues from earlier research that pointed to the potential importance of tiny neural storage bins known as "synaptic vesicles." Situated at nerve endings, synaptic vesicles continually work to store and release neurotransmitters. Dozens of proteins, including SV2, work to ensure that vesicles function properly. With standard screening experiments known as "entry assays," the scientists were able to zero in on SV2. To confirm that result, they acquired mice that were genetically engineered to carry reduced amounts of SV2. Without that protein around, the researchers found that botox was unable to wreak havoc.

The entire report is here.

For those who wish to learn the bioscience of botulism, this outline with links is most helpful. Botulinum toxin has killed many people who ingested the toxin unawares. Entire families have died within hours of eating badly preserved food that contained the toxin. The new findings discussed above may help to prevent and treat this toxicity. Because the next time you hear about botulinum toxicity may be on the civil defense channel. This is not a drill.

In Search of the Wild Molecule

We are swimming in a sea of molecules, unaware. That woman walking by has undiagnosed liver cancer, if we could only smell it. That student with a backpack is carrying explosives but who could tell? Those men working in that tunnel are being slowly poisoned by toxic gas, but who will warn them?

Purdue University researchers have developed a device that might open our collective eyes. The device is a miniature mass spectrometer, run on batteries. It has the potential for use at airport security, in hospital labs, and for environmental quality monitoring.

Researchers at Purdue University have shown how a new ultra-fast chemical-analysis tool has numerous promising uses for detecting everything from cancer in the liver to explosives residues on luggage and "biomarkers" in urine that provide an early warning for diseases.

The analytical chemists have most recently demonstrated how the technology, called desorption electrospray ionization, or DESI, rapidly detects the boundaries of cancerous tumors, information that could help ensure that surgeons remove the entire tumor.

"I wouldn't be surprised if pathologists are using this in operating rooms within two years," said R. Graham Cooks, the Henry Bohn Hass Distinguished Professor of Analytical Chemistry in Purdue's College of Science.

The technology has made it possible to speed up and simplify the use of a mass spectrometer, an analytical device that in its conventional form has been long established in modern laboratories. But while ordinary mass spectrometry is both time- and labor-intensive, the Purdue group has modified the technology to make it faster, more versatile and more portable.

.....A review paper about DESI and related techniques, which enable the direct chemical analysis of objects in an ordinary environment, will appear in the Friday (March 17) issue of the journal Science. The paper was written by Cooks, associate research scientist Zheng Ouyang, visiting scholar Zoltán Takáts and doctoral student Justin Wiseman, all in Purdue's Department of Chemistry. Several technical papers have been published about DESI experiments since the method was announced by the same laboratory in Science less than two years ago, but the new Science paper provides the first overall review of DESI and related techniques.

Mass spectrometry works by first turning molecules into ions, or electrically charged versions of themselves, which can be detected and analyzed.

"Having a charge enables you to not only detect molecules but also to measure their masses, which you can't do with neutral molecules," Cooks said.

Conventional mass spectrometers analyze samples that are specially prepared and placed in a vacuum chamber. The key DESI innovation is performing the ionization step in the air or directly on surfaces outside of the mass spectrometer's vacuum chamber.

In addition to DESI, Cooks' research group has designed and built a portable instrument that is roughly the size of a shoebox and weighs about 10 kilograms (22 pounds), compared to about 30 times that weight for a conventional mass spectrometer. The lightweight instrument can run on batteries, which means it can be carried anywhere....[it] promises to have applications in everything from airport security to medical diagnostics.

Read the rest here. Parallel research is going on at Oak Ridge National Lab.

Mass spectrometry has been around for several decades, but it is far more useful and powerful now. Soon, portable battery powered instruments will be used in the field, virtually anywhere.

Here is a brief primer on mass spectrometry. Here is a set of links to mass spectrometry resources, including tutorials.

Evolution gave us eyes, ears, noses, tongues, fingers, and other means of detecting and interpreting our environment. All sensory roads lead to the brain. The brain wants more information than our senses can give, thus the increasingly sophisticated analytical instruments and methods. The next step is a better brain.

China: The Ticking Time Bomb?

I recently posted on an interesting Foreign Policy article that looked at the dark side of China's rise. A few days ago, Winds of Change blog's Joe Katzman posted a look at some specific problems that China is facing.

We'll start with the rural time bomb:

"A peasant "time bomb" threatens to stunt China's rise to global economic superiority unless immediate measures are taken to fix the problem, say experts. The Chinese state has lost much of its legitimacy with the country's rural majority, a turnaround that could have increasingly adverse effects on the long-term socio-economic development of the country, according to Joshua Muldavin, an Asian studies expert at Sarah Lawrence College in New York.

With greater land seizures by the state and reduced levels of rural subsistence, more peasants are having to migrate to urban areas in search of work where disappointment often awaits, making "peasant landlessness ... a time bomb for the state," Muldavin told an audience Thursday at the Carnegie Endowment for International Peace.

"There are two Chinas," he said. One is for investors, and the other is the "rural hinterlands," where official corruption, a growing gap between rich and poor and unemployment led to some 87,000 incidents of unrest in China last year, said Muldavin. It is believed that many more go unreported."

......So, on to the demographic/ pension/ investment time bomb:

China's pension system is facing a demographic time bomb -- the consequence of the one-child policy -- which could seriously damage its future economic prospects, says a new report from Deutsche Bank's research department.

"Low retirement age compounds the demographic problem. China is graying fast but at a very low income level. Low effective retirement ages will see the working age population already reaching its peak between now and 2010 and will lift the old-age dependency ratio much higher than conventionally thought," says the report.

In effect, China is getting the demographic profile of an advanced industrial country with a mature welfare system, but with an economy still clambering out of developing status. And repairing the existing pension crisis is going to cost a minimum of 7 percent of its gross domestic product.

The DB survey lists three structural challenges in today's system that need to be addressed. The first is that the pension system is burdened by a large amount of legacy debt (i.e. unfunded liabilities from the old pension system).

The second is that decentralization of economic planning has led to fragmentation and a lack of transparency; and the third is that China's "immature capital markets make it difficult to find suitable investments with high returns."

Joe's post elicited several fascinating comments, including links to much more commentary and other articles. Read it all here.

Most investors get little gold bars in their eyes when they think of China's billion consumers. Anyone who tries to anticipate the geopolitical trends of the next decade or so needs to think more realistically.

The magnificent scientific achievements of (mostly) western research laboratories rests upon the economies of the western nations. If western economies fall like a house of cards due to a collapse of the Chinese banking system, then all of these miracle cures and devices that are just around the corner, will fail to materialise.

There is a point of no return, after which Communist Chinese corruption and Islamist fanaticism cannot stop the expansion of knowledge and human growth. But we are decades from that point, and very vulnerable yet. Keep a realistic eye on what is happening in those unstable, but critical parts of the world. If caught unprepared, many hundreds of millions of people could easily die in a short period of time. That is what critical instability means, in the modern world. The potential for more dead people than most persons can count.

It will be necessary to "look around" the news media--consider the news media a major obstacle to the acquisition of the valid states of the world. Be very skeptical, develop your own model of the world independent of journalists and journalism. Collect several sources of information and play them against each other.

Eating Germs to Stay Well

Consider this: you come down with productive cough, fever, chills. The chest Xray indicates an infiltrate in your lung fields. Your doctor prescribes antibiotics, and the symptoms subside, you feel better. What do you do next? According to this newsrelease, you should probably eat some germs. Lactobacilli to be specific. Normal gut flora that make vitamins for you and keep the bad bacteria and yeast from setting up shop in your belly. Read on:

Once outside the womb, we are bombarded by microbes and soon we have 10 times more microbes in our body than the number of cells that make up the human body.

It is the bad microbes that cause disease. Good microbes work with the body's immune system to keep the bad microbes at bay by crowding them out. In the symbiotic relationship between good and bad microbes, recent research has uncovered the importance of these good microbes.

“The good microbes - and this is where probiotics come in - keep the bad microbes in small numbers. But they also stimulate the immune system and improve our digestive function. That's the subject of research that has been going on for years,” Huffnagle says.

Probiotics are bacteria that we eat and they're good for our health. They are found in a number of foods that are readily available in the supermarket, and they taste good. You can support probiotic growth by increasing the amount of cultured dairy products you eat, such as cheeses and yogurt, and the foods that encourage probiotics from these dairy products to multiply even further: spices, tea, red wine, berries, apples and beans.

Huffnagle says that most of these good microbes exist within our body in the digestive track, with the largest number occurring in the small and large intestines.

“It's the job of these good microbes to stimulate our immune system, and the other job they do is to stimulate good digestive health,” he says.

Not only that, but the good bacteria are capable of producing antibiotics that attack bad bacteria. Follow along from this newsreport:

Nisin, a peptide, contains 34 amino acid residues and the unusual amino acids lanthionine, methyllanthionine, dehydroalanine and dehydro-amino-butyric acid. The latter are made by post-translational modification of proteins.

Nisin works well against Gram-positive bacteria and food-borne pathogens that cause botulism and listeriosis because it punches holes into cell membranes and binds to essential molecules in the disease-causing bacteria. Hitting on at least two targets reduces the risk of resistance occurring, van der Donk said.

The researchers synthesized nisin simply in a test tube by using a single cyclase enzyme to re-create the process that normally occurs in a strain of the bacterium Lactococcus lactis found naturally in milk. They demonstrated how just one protein (NisC) makes 10 new chemical bonds in a stereochemically defined fashion. Specifically, they showed that NisC is responsible for the formation of five characteristic thioether rings required for nisin's biological activity.

"Despite all the progress in synthetic chemistry, we cannot come close to making a compound like nisin efficiently," van der Donk said. "Synthetic chemists in the past needed 67 steps to make it, while nature uses just two enzymes. One of these is the cyclase whose activity we have demonstrated in this paper."

Read more here.

When you are born, your gastrointestinal tract is sterile. As soon as you began eating, your gut was colonised by bacteria. If you were breast-fed, you were lucky enough to receive booster nutrients that promoted bifidobacteria, which prevent colonisation by pathogenic bacteria. Other food sources, although nutritious enough, lack that advantage.

Gut bacteria produce vitamins B12 and K for us, as well as keeping out the bad germs. Genetically engineered gut bacteria could do much more for us, and would be a natural way of introducing genetically engineered resveratrol, curcumin, or capsaicin or other natural substances known to counter cancer or promote longevity.

Most of us do not like to think about what goes on inside of us, until we get sick, then we definitely want a physician to think very hard about what is inside of us and how to make it better. But would it not be better to stay well, if you had the choice?

Hot Chili Peppers Prostate Cancer to Death

You can find places in the world where the measure of a man is how well he holds his chili peppers. According to this news report, men who like their chilis are less apt to suffer from prostate cancer than their less manly fellows. From the newsrelease:

Capsaicin induced approximately 80 percent of prostate cancer cells growing in mice to follow the molecular pathways leading to apoptosis. Prostate cancer tumors treated with capsaicin were about one-fifth the size of tumors in non-treated mice.

"Capsaicin had a profound anti-proliferative effect on human prostate cancer cells in culture," said Sören Lehmann, M.D., Ph.D., visiting scientist at the Cedars-Sinai Medical Center and the UCLA School of Medicine. "It also dramatically slowed the development of prostate tumors formed by those human cell lines grown in mouse models."

Lehmann estimated that the dose of pepper extract fed orally to the mice was equivalent to giving 400 milligrams of capsaicin three times a week to a 200 pound man, roughly equivalent to between three and eight fresh habañera peppers – depending on the pepper's capsaicin content. Habañeras are the highest rated pepper for capsaicin content according to the Scoville heat index. Habañero peppers, which are native to the Yucatan, typically contain up to 300,000 Scoville units. The more popular Jalapeño variety from Oaxaca, Mexico, and the southwest United States, contains 2,500 to 5,000 Scoville units.

....Apoptosis is a normal cellular event in many tissues that maintains a balance between newer replacement cells and aged or worn cells. In contrast, cancer cells seek to be immortal and often dodge apoptosis by mutating or deregulating the genes that participate in programmed cell death.

"When we noticed that capsaicin affected NF-kappa Beta, that was an indication that we might expect some of the apoptotic proteins to be affected," said the study's senior author, Phillip Koeffler, M.D., director of Hematology and Oncology, Cedars-Sinai Medical Center, and professor at UCLA.

The pepper extract also curbed the growth of prostate cancer cells through regulation of androgen receptors, the steroid activated proteins that control expression of specific growth relating genes.

In prostate cancer cells whose growth is dependent on testosterone, the predominant male sex steroid, capsaicin reduced cell proliferation in a dose-dependent manner. Increased concentrations of capsaicin caused more prostate cancer cells to freeze in a non-proliferative state, called G0/G1.

Prostate cancer cells that are androgen independent reacted to capsaicin in a similar manner. Capsaicin reduced the amount of androgen receptor that the tumor cells produced, but did not interfere with normal movement of androgen receptor into the nucleus of the cancer cells where the steroid receptor acts to regulate androgen target genes such as prostate specific antigen (PSA). Capsaicin also interfered with the action of androgen receptors even in cells that were modified to produce excess numbers of androgen receptors.

The hot pepper component also reduced cancer cell production of PSA, a protein that often is produced in high quantities by prostate tumors and can signal the presence of prostate cancer in men. PSA content in the blood of men is used as a diagnostic prostate cancer screening measure. PSA is regulated by androgens, and capsaicin limited androgen-induced increases of PSA in the cancer cell lines.

Read the entire report here.

I hardly need an excuse to eat hot chilis, but this research report gives me a reason to look into the epidemiology of chilis and cancer a bit more. Stay tuned.

Why so Afraid, Little Flower? Is it your Amygdala Again?

We are all at the mercy of our genes. Your genes determine the color of your eyes, your hair, your approximate height, and much of your personality. Are you sanguine? Are you cheerful? Are you fearful? Activation of your amygdalae has a lot to do with serotonin levels in synapses, and the level of negative emotions you experience. Serotonin levels in the synapse are largely determined by your genes. "How Genes Make up Your Mind" is an interesting article in the Science and Consciousness Review.

Genes control the development of neurons to make up brains, but they also govern neuronal gene expression during our daily lives. The sleep-waking cycle is controlled by neurochemicals emerging from cells at the base of the brain. Genes control how neurons communicate with serotonin, dopamine or other neurotransmitters (cache). Genes are responsible for every step of the neurotransmitter cycle, including the formation, transport, pre-synaptic expression and post-synaptic reception of the transmitter (see Figure 1). Genes work at every level of the neural process. They are the fundamental building blocks for both the structure and the functioning of the brain.

....How do genes influence the emotional workings of brains? Recent studies now show that naturally occurring genetic variations - called polymorphisms (cache) - which code for serotonin affects our emotional reactions and thoughts. Humans have two common variations of a promoter region of the serotonin transporter gene (5-HTTLPR); a short (s) and a long (l) version. It has been shown that two allelic (cache) copies of the long variant leads to higher concentration of 5-HTT mRNA, which leads to a doubled reuptake of serotonin, compared to one or two short allelic variations. People who have two copies of the long genetic sequence in this region have less serotonin available in the synapse, due to the higher reuptake of the neurotransmitter.

....The researchers found that the actvation of the two amygdalas differed between the two groups (see Figure 4). The s group showed a significantly higher amygdala activation than the l group. In other words, the level of amygdala activation depended on what genetic makeup a person had. Having a short version of the 5-HTT genetic code leads to a higher level of synaptic serotonine, which again leads to a higher level of amygdalar response to aversive stimuli. This is consistent with the prediction described above.

While these results have provided us new information about how genes regulate brain function, one can ask: does this have any effect on thought and behaviour? Indeed it has! Studies demonstrate that carriers of the s allele, compared to l allele carriers, are more likely to show abnormal levels of anxiety (5) develop affective illness (6) and even acquire conditioned fear responses (7). Variations in the genetic makeup of the serotonin system has profound influence on our experience and behavior. Thoughts are shaped by genes.

The original article contains several useful links. Check it out.

Not everyone wins the genetic lottery. At least now we are beginning to understand what happens, and what might be done to bring the advantages of good genes to the amygdalas of everyone.

Nanotech that Heals Brain Damage

In a recent post I described a peptide bio-gel that promotes cell growth, and acts as a three dimensional scaffold for tissue healing and cell culture. Now a cognitive science researcher at MIT has developed a liquid solution of peptide chains that self assembles into nano-fibres inside damaged brain. These nano-fibres then form a scaffold for the re-growth of severed nerves--an incredible achievement in the central nervous system. Here is the report:

Although victims of stroke and traumatic brain and spinal cord injuries sometimes recover through rehabilitation, they often have permanent disabilities, in part, because scar tissue and regulatory chemicals in the brain slow nerve growth, preventing nerve tissue from repairing itself. Now a treatment that has restored lost vision in lab animals appears to overcome these obstacles, allowing a mass of nerve cells to regrow after being cut.

"We think this is the basis of reconstructive brain surgery -- which is something nobody has ever heard of before," says Rutledge Ellis-Behnke, a researcher on the project and a brain and cognitive sciences researcher at MIT.

The treatment, described online this week in the Proceedings of the National Academy of Sciences and performed at MIT, Hong Kong University, and Fourth Military Medical University in China, may be available to humans in trials in as little as three years if all goes well in large-animal studies, the researchers say.

In their experiments, the researchers first cut into a brain structure that conveys signals for vision, causing the small lab animals to be blinded in one eye. They then injected a clear fluid containing chains of amino acids into the damaged area. Once in the environment of the brain, these chains, called peptides, bind to one another, assembling into nano-scale fibers that bridge the gap left by the damage. The mesh of fibers prevents scar tissue from forming and may also encourage cell growth (the researchers are still investigating the mechanisms involved).

As a result, nerve cells restored severed connections, allowing 75 percent of the animals to see well enough to detect and turn toward food. The treatment restored around 30,000 nerve connections, compared with 25-30 connections made possible in other experimental treatments, Ellis-Behnke says.

Read the rest here.

Repairing damage in the brain and spinal cord has always been virtually impossible, due to the resistance to regrowth of CNS neurons. Clearly something in the peptide fibres encourages the nerves to regrow, and reconnect. Just like something in the peptide gel of the tissue scaffold in the earlier article encourages cultured cells to grow.

In those two research projects, we can see the beginnings of the development of both the growing of artificial replacement organs, and the repair of central nervous system damage in the brain and spinal cord. Now we need to watch for research that replicates these findings, and takes them further.

Global Warming? It's the Water, Stupid!

Getting excited about global warming at this early stage in understanding of climate science has always struck me as rather premature. There are quite a few scientists who feel the same way, although for political reasons they may feel the need to keep a low profile on that topic. Vladimir Shaidurov is a member of the Russian Academy of Sciences, and his theory of global warming says that the warming of the past several decades is due to changes in the composition of water in the atmosphere, rather than carbon dioxide. Here is a report on this unconventional theory.

However, the most potent greenhouse gas is water, explains Shaidurov and it is this compound on which his study focuses. According to Shaidurov, only small changes in the atmospheric levels of water, in the form of vapour and ice crystals can contribute to significant changes to the temperature of the earth's surface, which far outweighs the effects of carbon dioxide and other gases released by human activities. Just a rise of 1% of water vapour could raise the global average temperature of Earth's surface more then 4 degrees Celsius.

The role of water vapour in controlling our planet's temperature was hinted at almost 150 years ago by Irish scientist John Tyndall. Tyndall, who also provided an explanation as to why the sky is blue, explained the problem: "The strongest radiant heat absorber, is the most important gas controlling Earth's temperature. Without water vapour, he wrote, the Earth's surface would be 'held fast in the iron grip of frost'." Thin clouds at high altitude allow sunlight to reach the earth's surface, but reflect back radiated heat, acting as an insulating greenhouse layer.

Water vapour levels are even less within our control than CO2 levels. According to Andrew E. Dessler of the Texas A & M University writing in 'The Science and Politics of Global Climate Change', "Human activities do not control all greenhouse gases, however. The most powerful greenhouse gas in the atmosphere is water vapour, he says, "Human activities have little direct control over its atmospheric abundance, which is controlled instead by the worldwide balance between evaporation from the oceans and precipitation."

As such, Shaidurov has concluded that only an enormous natural phenomenon, such as an asteroid or comet impact or airburst, could seriously disturb atmospheric water levels, destroying persistent so-called 'silver', or noctilucent, clouds composed of ice crystals in the high altitude mesosphere (50 to 85km).

Read the entire report here.

Peak oil and global warming are custom made catastrophes that get a great deal of political spin in the media. That makes them neither right nor wrong, merely suspect. Anything that journalists consider significant or newsworthy should always be viewed skeptically.

New Screening Test 100,000 Times Better for Early Cancer Detection

This is a very significant development in the search for better ways to detect cancer early, while it is still treatable. A new screening method called FACTT (for Florescent Amplification Catalyzed by T7-polymerase Technique) is 100,000 times more sensitive for detecting proteins than the current method, ELISA (enzyme-linked immunoadsorbent assay).

This newsbrief from Innovations Report gives more details:

Senior author Mark I. Greene MD, PhD, the John Eckman Professor of Medical Science, Hongtao Zhang, PhD research specialist; Xin Cheng, PhD, research investigator, and Mark Richter, a research technician in Greene’s lab, report their findings in the advanced online publication of Nature Medicine.

"The current ELISA tests can only detect proteins when they are in high abundance," says Zhang. "But the problem is that many of the functional proteins – those that have a role in determining your health – exist in very low amounts until diseases are apparent and cannot be detected or measured at early stages of medical pathology. It was important to develop a technique that can detect these rare molecules to detect abnormalities at an early stage."

The FACTT technology uses a different enzyme amplification system so quantitative signals can be obtained from even a few protein molecules compared to ELISA. "The technology is remarkably adaptable to any protein and can be performed in an automated format," notes Greene. He states that the technology will soon be robotized so as to be able to screen for many rare disease-causing proteins using tiny amounts of blood. "It is even possible that one could screen for multiple diseases at the same time and produce a precise accounting of whether disease-causing molecules are present at an early time when disease can be readily treated," adds Greene.

....The researchers compared detection of Her2/neu in the blood between ELISA and FACTT. Her2/neu proteins were in fact first identified by the Greene laboratory in the early 1980s, and the Her2/neu gene was found by other scientists to be overexpressed in breast cancer. Her2/neu is normally a low-abundance molecule that becomes overexpressed in more than 30 percent of primary breast, ovarian, and pancreatic tumors. Part of the Her2/neu molecule is shed from the surface of tumor cells and has been detected in the blood of breast-cancer patients. Higher blood concentrations of Her2/neu correlate with a lower response rate to chemotherapy and shorter survival time after relapse.

....Greene’s laboratory established many of the principles of targeted therapy for Her2/neu tumors and the prototype antibodies that led to the development of Herceptin, a similar antibody molecule that was created by Genentech. The Greene laboratory also previously showed that early treatment of Her2/neu tumors with targeted monoclonal antibodies in animal models led to far more significant prevention of tumor growth as well as tumor emergence and reoccurrence.

Greene stresses that early treatment is far more effective than treating advanced tumors with the same antibodies. Recent clinical trials support the notion that early treatment prevents tumor reoccurrence in women with breast tumors. FACTT technology represents a way to couple early diagnosis with early treatment to prevent tumor emergence.

Read the entire report here.

In years past, detecting cancer earlier was not always better, given the severe limitations on treatment choice. The direction of research is toward treatments that can eradicate a tumor before it is large enough for detection, except through chemical means of detecting biomarker proteins. In other words, treatments will be both effective enough and benign enough to use on a patient, long before the tumor is large enough to detect with xray or physical exam. That is the sort of treatment that is needed to take advantage of this tremendous advance in detection sensitivity.

Women on the Verge of a Solar Energy Revolution

One of the principal problems with using solar energy is that the sun only shines part of the day. When the sun is not shining, its energy cannot be used, unless it has been stored. A lot of methods have been proposed for storing the sun's energy after sundown, for later use.

One of the more interesting proposals has won a prestigious NSF award for Dr. Sherine Obare, a chemist at Western Michigan University. From WMU News:

Obare's project, "Rationally Assembled Nanoparticles for Multi-Electron Transfer Processes," seeks to create nanoscale materials that trap and store the sun's energy and use that energy to carry out chemical reactions for specialized purposes, including breaking down pollutants in groundwater and generating hydrogen for use as an alternative fuel. She is focusing on nanomaterials--materials organized atom by atom or molecule by molecule--because they are have unique properties that can be manipulated and exploited for important applications such as those.

The project is inspired by how nature is able to use intricate pathways to carry out important reactions, Obare says, noting as an example that plants use sunlight to carry out photosynthesis. But what makes her research novel is that she is using nanomaterials to store the energy as electrons, and then initiate chemical reactions even when sunlight is not present.

Very fascinating. Read the entire report here.

Another chemist who is pursuing research in a similar area of study is Dr. Norma Tacconi at University of Texas Arlington. From Dr. Tacconi's webpage:

The coupling of reduction and protonation is an essential feature in most natural light-activated energy-storing processes and these complexes may ultimately be capable of driving proton-coupled, multi-electron transfer reaction of the type desired for facile H2 production or O2 reduction.

These scientists are working to create chemical and nanoparticle complexes that can store solar energy in the form of electrons, for use in fueling chemical reactions of various types, including the generation of hydrogen, and breaking down pollutants.

Nature is prolific in generating energy from the sun, using photosynthesis. Science is learning to do similar tricks using solar power.

Resurrecting Tumor Suppressors to Combat Cancer

The human body is prone to developing cancer, from a very early stage of life, until the end of life. The human genome has several built in tumor suppressor genes, whose protein products suppress the formation of tumors. It is important for these tumor suppressor genes to continue expressing their tumor suppressor proteins as long as the person lives. Over time, DNA can be damaged or altered, leading to loss of function of these protective genes. One way these genes can lose their ability to make protective proteins is through methylation.

Methylation is the gradual addition of chemical units known as methyl groups to genes, and as these groups accumulate, the gene gradually shuts down. Some drugs prevent the methylation process, releasing the gene to produce its tumor suppressor. In fact, methylation is a salient characteristic of cancer cells, and can be used as a biomarker for cancer.

Fortunately, researchers are developing new drugs called "hypomethylating agens" that have the ability to remove the methyl groups and restore function to tumor suppressor genes. This Bio.com report discusses one of these new drugs:

The drug, decitabine, is designed to turn on genes that cancer had switched off, and in this study, patients who were treated with it achieved a significantly higher overall response rate, compared to patients receiving supportive care, which includes transfusions of red blood cells and platelets.

Results of the randomized Phase III clinical trial, published March 13, 2006 in the online version of the journal Cancer, also concluded that in treated patients who responded to the drug, the median time to progression of the disease, or death, was 17.5 months, compared to 9.8 months in patients who did not.

"This is a very promising drug that we believe works even better when patients use it for a period that is longer than that tested in this trial," says lead author, Hagop Kantarjian, M.D., chair of the Department of Leukemia at M. D. Anderson.

....Decitabine is a "biological disease modifier" that was given fast-track approval by the Food and Drug Administration in April 2003.

It is a DNA hypomethylating agent that fights cancer by reversing a chemical process (methylation) that turns off tumor-suppressor genes that protect cells from becoming cancerous.

Other hypomethylating agents are being used and developed for several other types of malignancy including leukemia and breast cancer.

These drugs work by turning back time, as it were--gene time. Other drugs are being developed to turn back time for the entire genome. It is a race against the clock, but then, it always has been.

Programming Plant Cells to make Human Vaccines

Humans have coexisted with plants and microbes from the beginning of human evolution. As humans learned to domesticate various plants, their food supply exploded. Early shamans and healers learned to use herbs for healing. In the modern era, microbes have jumped ahead of plants in the biotech production of gene-engineered pharmaceuticals, but plant scientists are determined that plants can be useful pharm-factories of gene engineered medicines and vaccines.

This Eurekalert newsrelease reports on efforts to design a vaccine against HIV in plants.

By creating fusion molecules, the researchers have found a way to make plants produce more of the molecules (antigens) needed for vaccines. At the same time, they may also have discovered a way of producing better targeted vaccines. Obregon and her colleagues in Dr Julian Ma's laboratory are working with the p24 core protein of the Human Immunodeficiency Virus (HIV). This protein plays a central role in eliciting the immune response to HIV infection, and is therefore likely to be an integral part of any multicomponent vaccine for HIV.

Plants have already been used to produce many types of vaccine molecules, but a consistent problem has been achieving adequate levels of protein expression in order to make them viable as bioreactors for vaccines.

Obregon and her colleagues have found a way to significantly boost HIV-1 p24 protein production in plants by producing an entirely new molecule – a fusion of the HIV-1 p24 protein and part of another protein, human immunoglobulin A (IgA) - a major component of the immune system. The team found that the HIV-1p24 antigen produced in this way elicited appropriate immune response in mice.

This brief report discusses early efforts to develop a vaccine against avian flu, using plants. This blog reports on efforts to use the tobacco plant to develop a vaccine against the black plague, yersinia pestis.

Transgenic plants are becoming more and more useful as plant scientists develop their techniques. The mitigation of many modern problems lies in the intelligent use of transgenic plants, animals, and microbes. In this posting I briefly discussed the use of engineered plants for mitigating global warming. The limits of the human imagination are currently restricting the human vision of a cleaner and healthier world.

Stem Cells On the Rag, In the Teeth, and more

Remember when most people thought the only source for stem cells was an embryo? You can certainly get totipotent stem cells from embryos, but it will be some time before researchers can control totipotent stem cells to everyone's satisfaction. Sometimes stem cells from more mature tissues will satisfy a need. It is important to hunt down these stem cell sources so that we can learn how useful those cells can be.

Stem Cell Research Progress Blog does a very good job of following the news in stem cell research. In recent posts, here and here, Anne Leonard discusses alternative sources of stem cells that are being evaluated.

Researchers in Japan have been looking for alternative sources of stem cells which may be of help in promoting the growth of heart muscle tissue. They have found stem cells in menstrual blood and in umbilical cord blood which have the cardiac gene expression and protein expression necessary for repairing muscles (as opposed to blood vessels). The menstrual blood has the additional advantages of being easily obtainable and rich in stem cells.

She goes on to discuss research with stem cells derived from pig fat and human bone marrow. In the second post, she discusses stem cells from teeth:

Two Asian newspapers are reporting that researchers in Japan at Osaka University and National Institute of Advanced Industrial Science and Technology’s Research Institute for Cell Engineering used stem cells derived from the germ of human wisdom teeth to repair damaged liver and bones in rats. The story was originally published in the Japanese paper the Daily Yomiuri and reprinted with slight variations on the Chinese site Xinhua. The article reports that the tooth germ can be changed into bone, liver, or nerve cells by stimulating it with hormones, and that the stem cells grow far more quickly than those taken from bone marrow.

Today's Stem Cell Research reports on umbilical cord blood stem cell extraction and isolation, and offers a video. Here is a report on spinal cord regeneration stem cell research, and here are some educational materials for teaching about stem cells, from the same website. Check out the Virtual Stem Cell Laboratory.

Stem cells are being found in many locations, even in the human placenta. Embryonic stem cells taken at the proper stage can potentially develop into any cell type. But at the rate that cell biologists are learning to control differentiation and de-differentiation of cells, that characteristic might not set embryonic stem cells apart for long. Stay tuned.

Thinking Makes it Happen

When the brain is working, it generates electromagnetism. A well designed detector of electricity or magnetism can monitor the action of the brain. That is simple EEG or MEG. But if you provide the brain with feedback of its own behaviour, while continuing to monitor the brain, you create a neurofeedback loop.

Clever neuroscientists and computer scientists in Berlin have developed a device that allows persons to operate a computer keyboard using their brainwaves.
This device comes under the category of brain-machine interfaces. It is easy to imagine that if a person can control a computer keyboard with his thoughts, then anything that can be interfaced with an electrical or electromagnetic actuator can be controlled by a person's thoughts.

I find the concept of a wearable robotic exoskeleton, to be one of many things that could be controlled by brainwaves. It would not be hard to equip such an exoskeleton with actuators and brainwave interfaces.
JW Bats of Our Technological Future, reports on this robot hand that detects nerve impulses and moves accordingly. The hand contains pressure sensors, allowing it to pick up and handle very delicate objects.

If one were to combine the brainwave interface with an actuator-equipped exoskeleton, with pressure detecting sensors on the robotic appendages, you might have the basis for an ambulatory device that could replace the wheelchair--for paraplegics, quadriplegics, and victims of disabling neuro/musculo/skeletal diseases. Neurofeedback has a lot of potential.

As I made clear in this post, I prefer biological solutions over hardware solutions. But as I suggested here, and in other posts, I am agreeable to using hardware solutions as a stopgap, while the biological solutions are still being worked out. The goal is full functionality--and more. Getting from here to there will be a winding road.

Hat tip Singularity News.

Peeping Toms of Neuroscience: No More Secrets

We are fortunate these days, to have available the expertise of legions of neuroscientists, all for the price of a mouse click. Eide Neurolearning Blog reports on the obvious neuro-image differences in brain activity between the pro golfer and the beginning golfer.
This fMRI image taken from ScienceDaily, illustrates sex or gender differences in the amount of gray and white matter used for general intelligence.
While there are essentially no disparities in general intelligence between the sexes, a UC Irvine study has found significant differences in brain areas where males and females manifest their intelligence.

The study shows women having more white matter and men more gray matter related to intellectual skill, revealing that no single neuroanatomical structure determines general intelligence and that different types of brain designs are capable of producing equivalent intellectual performance.

“These findings suggest that human evolution has created two different types of brains designed for equally intelligent behavior,” said Richard Haier, professor of psychology in the Department of Pediatrics and longtime human intelligence researcher, who led the study with colleagues at UCI and the University of New Mexico. “In addition, by pinpointing these gender-based intelligence areas, the study has the potential to aid research on dementia and other cognitive-impairment diseases in the brain.”

Functional MRI, or fMRI, is a powerful imaging technology that looks inside the brain while it works. Not only will it tell you what part of the brain is working at any given time, it will also give you an idea of how hard that part of the brain is working.

This excellent article discusses the use of fMRI in intelligence studies, and has some incredible graphic images. The thoughtful sensitivity of the authors when discussing societal implications of the research, and necessary ethical concerns of researchers, is encouraging. And if that masterful review only served to whet your appetite for more, consult these neural correlates of reasoning.

The human brain sits exposed. If the person lies, his brain will show a different picture than if he tells the truth. If the person has to work harder to solve a problem than his sister did, his brain image will give him away. It is getting harder to hide from the peeping Toms of neuroscience.