The Alchemist Newsletter: August 12, 2008

Van Gogh was two-timing his canvas, the Alchemist learns this week, thanks to novel X-ray studies of a seemingly innocuous piece called Patch of Grass, which hides a woman's face beneath its green and peasant landscape. Professional wine tasters and vintners with a penchant for pepping up their plonk should have something new to worry about thanks to the development of an electronic tongue for detecting adulterated wines and those labeled with the wrong vintage. In biochemistry, sex and sleep turn out to be inextricably entangled, at least in the world of the lab technician's favorite nematode worm, Caenorhabditis elegans. Traditional Chinese Medicine is heavily marketed despite a lack of clinical evidence of efficacy of many of the remedies. However, The Alchemist hears of a traditional remedy for allergy that, toxic components removed, could work to prevent life-threatening peanut allergy. The world of red hot chili peppers wouldn't be so hot if it were not for nibbling insects and a fungus that infects the chilis. Finally, a grant to get the blood pumping will fund research into how the brain controls blood pressure and could eventually lead to new treatments for hypertension and cut deaths from cardiovascular disease.

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van Gogh's green and peasant landscape

European researchers have used a powerful new X-ray technique to reveal a hidden van Gogh beneath another of his paintings. The portrait of an unknown peasant woman apparently lies below one of the Dutch Master's lesser known green and pleasant landscapes. The work could now be used to seek out, in unprecedented detail, masterpieces hidden beneath other paintings. The painting, Patch of Grass, was not considered one of his most famous works but that has now changed thanks to work by an international European research team. Joris Dik of Delft University of Technology in The Netherlands and colleagues including chemist Koen Janssens of the University of Antwerp, Belgium, used a new technique with synchrotron radiation induced X-ray fluorescence spectroscopy in their study. The technique can reveal unprecedented contrast as well as distinguishing between different heavy metals in the pigment so allowing the researchers to guess at the skin tones used in the portrait.

Looking through Van Gogh

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A taste for wine

European scientists have built a portable "electronic tongue" based on six ISFET sensor devices that can broadly detect common ions and heavy metals. The sensors are coupled to a flow injection analysis (FIA) system and then the data fed into a chemometrics system for pattern recognition. The team led by Cecilia Jimenez-Jorquera of the Barcelona Institute of Microelectronics, Spain, quickly and inexpensively reveals information about grape variety and even vintage at the press of a button. The researchers say the device can be trained to "taste" new varieties as required and so will be a boon to wine producers looking for rapid online quality control. The same system might also be used by the authorities to check for vintage fraud or adulterated wine.

The wine fraud detective

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Worm ways

For many, it's a tough call - sex or sleep? But, for the millimeter-long nematode worm, Caenorhabditis elegans, the choice is a matter of straightforward chemistry. Writing in the journal Nature, Arthur Edison of the University of Florida, Frank Schroeder of Cornell University, Jagan Srinivasan, of California Institute of Technology and their colleagues, and co-workers at the US Department of Agriculture (USDA), describe how they used a highly sensitive NMR spectroscopy probe to identify tiny quantities of a novel group of pheromones from the soil-dwelling nematode that act as the organism's mating signal in times of plenty, but trigger hibernation when food is in short supply. There are countless nematode species that devastate crops and others are human gut parasites. The new study may lead to a better understanding of nematode biochemistry in general and one day to novel crop protection and anthelminthics for treating the parasites.

Mate or hibernate? That's the question worm pheromones answer

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Herbal synergy and peanut allergy

Could an unhyped finding for a Chinese herb lead to a very desirable treatment for peanut allergy? What happens though if some people turn out to be allergic to the herb? "Food Allergy Herbal Formula" has been tested in an animal model by researchers at the Mount Sinai Medical Center and Johns Hopkins University with funding by private foundations and government grants rather than any manufacturer or business interest. The results appeared in the Journal of Allergy and Clinical Immunology. The researchers had tested FAHF-1 on a mouse model of peanut allergy and demonstrated that it blocks anaphylaxis as well as reducing mast cell degranulation, histamine release, peanut-specific serum IgE levels, and Th2 cytokine secretion. However, the first formulation tested, FAHF-1, which contained wild ginger and so toxic aristolochic acid and Fu zi, which contains poisonous aconite. To make a clinically viable preparation, FAHF-2, the researchers removed these two ingredients and demonstrated similar efficacy. The researchers have tested the remaining ingredients in isolation but found only marginal effects, apparently there is a synergistic effect of the active ingredients.

An Herbal Cure for Peanut Allergy?

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Bugging red hot chili peppers

The spiciness of red hot chili peppers is a defense mechanism against a microbial fungus that these fruits through punctures made in the outer skin by insects. The fungus, from a large genus called Fusarium, destroys the plant's seeds before they can be eaten by birds and widely distributed. Now, Joshua Tewksbury, a University of Washington, and colleagues have found that not all individual plants of the same species produce the hot capsaicinoid compounds to the same levels. In the same plant population they found that fruit on one plant could be hotter than a jalapeno while fruit from other plants of the same species might be as mild as a bell pepper. However, the key factor was that the hottest peppers came from plants exposed to larger populations of hemipteran insects that attack the chilies and leave them more vulnerable to fungus. The finding could lead to new ways to control the heat of chilis and perhaps grow even hotter peppers.

Bugs Put the Heat in Chili Peppers

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A red-blooded grant

$1.2 million has been awarded to Eric Lazartigues, assistant professor of pharmacology at LSU Health Sciences Center New Orleans School of Medicine by the National Heart, Lung, and Blood Institute with the aim of funding a five-year research proposal to advance our understanding of how the brain regulated blood pressure and affects the development of hypertension. The research could ultimately pave the way for the development of new treatments for cardiovascular disease, a major killer in the developed world. Lazartigues' research group was the first to identify the presence of the protein angiotensin-converting enzyme 2 (ACE2) in the mouse brain. ACE2 degrades the hormone, angiotensin-II, in the brain, and so affects blood pressure.

LSUHSC's Lazartigues awarded $1.2 million grant

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-- David Bradley, Science Journalist