Isegoria

Fortified Cassava Could Provide A Day's Nutrition In A Single Meal:

Scientists have determined how to fortify the cassava plant, a staple root crop in many developing countries, with enough vitamins, minerals and protein to provide the poor and malnourished with a day’s worth of nutrition in a single meal.

The researchers have further engineered the cassava plant so it can resist the crop’s most damaging viral threats and are refining methods to reduce cyanogens, substances that yield poisonous cyanide if they are not properly removed from the food before consumption. The reduction of cyanogens also can shorten the time it takes to process the plant into food, which typically requires three to six days to complete.

Studies also are under way to extend the plant’s shelf life so it can be stored or shipped.

The international team of scientists hopes to translate the greenhouse research into a product that can be field tested in at least two African nations by 2010. Funded by more than $12.1 million in grants from the Bill & Melinda Gates Foundation, the group of researchers is led by Richard Sayre, a professor of plant cellular and molecular biology at Ohio State University.

Today is the 150th anniversary of the Theory of Evolution — or of its presentation to the scientific world:

1858: The Linnaean Society of London listens to the reading of a composite paper on how natural selection accounts for the evolution and variety of species. The authors are Charles Darwin and Alfred Russel Wallace. Modern biology is born.

Scientists of the time knew that evolution occurred. The fossil record showed evidence of life forms that no longer existed. The question was, how did it occur?

Darwin had been working on his theory since 1837, soon after his epic voyage on the HMS Beagle. The hypermethodical naturalist wanted not only to classify the prodigious variation he had observed, but also to explain how it came to be.

He felt he would need to publish extensive documentation of natural selection to overcome popular resistance to so radical a notion. So he planned a comprehensive, multivolume work to convince scientists and the world.

Darwin was still working on his magnum opus when in June 1858 he received a letter from an English naturalist working in Malaysia. Alfred Russel Wallace was young and brash. When he conceived of natural selection, he didn’t plan a 10-volume lifework. He just dashed off a quick paper on the subject and mailed it to the author of The Voyage of the Beagle, asking him to refer it for publication if it seemed good enough.

Darwin was crestfallen. Was he about to lose credit for two decades of work? Wallace had suggested that Darwin forward the paper to Scottish geologist Charles Lyell. Along with English botanist Joseph Hooker, Lyell was one of a small handful of people Darwin had shown early drafts of his own work on natural selection.

Darwin wrote to Lyell and Hooker, and they arranged for a joint paper to be read at the forthcoming meeting of the Linnaean Society of London. (Founded in 1788 and named for Carl Linnaeus, the Swedish scientist who devised the binomial system of taxonomy, it is the world’s oldest active biological society.)

Neither Darwin nor Wallace attended the meeting. Wallace was still in Malaysia. Darwin was at home with his wife mourning the death of their 19-month-old son just three days earlier.

The secretary of the society read the 18-page paper, comprising four parts:

1. The readers’ own letter of introduction explaining the extraordinary circumstances;
2. An excerpt from Darwin’s unpublished draft, part of a chapter titled, “On the Variation of Organic Beings in a State of Nature; on the Natural Means of Selection; on the Comparison of Domestic Races and True Species”;
3. An abstract of Darwin’s 1857 letter on the subject to Harvard University botanist Asa Gray;
4. Wallace’s manuscript, “On the Tendency of Varieties to Depart Indefinitely From the Original Type.”

The paper and the meeting did not cause an immediate sensation. Other papers were read the same day. The society had routine business to transact. The meeting was long (.pdf). But the paper was accepted for publication in the society’s Proceedings later that year.

Was this a remarkable case of simultaneous discovery? Not quite. It was more like simultaneous announcement. What is remarkable is that both Darwin and Wallace credited their central insight to reading Thomas Malthus’ essay, Population, first published in 1798.

Darwin read Malthus in 1838 and immediately realized how it applied to his own work. Wallace had read it around 1846, but first saw its import for explaining evolution while he lay recovering from fever in Malaysia a dozen years later.

Malthus observed that population was held in check because not every individual would survive to reproduce. As Wallace wrote, “It suddenly flashed upon me … in every generation the inferior would inevitably be killed off and the superior would remain — that is, the fittest would survive.”

But the same differences in temperament that had led to Darwin’s delay and Wallace’s rush to publication now worked to Darwin’s advantage … and ultimately greater fame. Wallace was already on to his next big thing: amassing huge collections of natural specimens in hopes of winning both fame and fortune.

Darwin was on to his next big thing: At the urging of his friends, he published a magnificent one-volume summary of his work, On the Origin of Species by Means of Natural Selection, or the Preservation of Favoured Races in the Struggle for Life, in 1859.

That produced an intellectual and cultural splash, perhaps the largest of the 19th century. And it is the sesquicentennial of the book next year, along with the bicentennial of Darwin’s birth, which will be more widely marked than the 1858 event.

Jürg Gertsch, of ETH Zürich, and his collaborators from three other universities have provided some proof that marijuana is a powerful medicine — not because of its supposed active ingredient, THC, but because of another ingredient, beta-caryophyllene:

Gertsch and his team published their findings on June 23 in the Proceedings of the National Academy of Sciences.They focused on the anti-inflammatory properties of the impressive substance — testing it on immune cells called monocytes and also in mice.

Since beta-caryophyllene seems to be powerful, occurs naturally in many foods, and does not get people high, it could turn out to be a nearly ideal medication. The organic compound is also phenomenally cheap. Sigma Aldrich sells it, in kosher form, for forty-two dollars per kilogram.

Of course, since it’s already cheaply available, it’s in no one’s interest to spend the money to get it FDA approved.

Fake virus could make safe new vaccines:

The researchers used a unique method to make their virus, relying on a built-in redundancy in DNA, the material that carries genetic instructions in organisms.

DNA’s code is written using just four nucleic acids, represented by the letters A, C, T and G. These are combined in various ways to make amino acids, which in turn make proteins.

It is possible to make an amino acid with more than one combination of these letters — for example, GCC and GCG both code for the amino acid alanine. For unknown reasons, organisms favor certain combinations.

Futcher’s team made their polio virus using the less-favored combinations of the virus’s genetic code.

They hoped these would stimulate the immune system in the same way as “wild-type” polio, without causing disease, and that is what appears to have happened, they wrote.

Each difference in the genetic code weakened the virus in a different way.

“This ‘death by a thousand cuts’ strategy could be generally applicable to attenuating many kinds of viruses,” they wrote.

“Even for an inactivated rather than live virus approach, these features would allow a vaccine to be made from a safer starting material than the corresponding wild-type virus.”

Polio vaccines have virtually eradicated the disease in most countries. But an oral vaccine that uses a weakened version of a live polio virus can sometimes get back into the water supply and mutate into a form that can infect people.

Doctors have been looking for a safer yet effective polio vaccine that is as easy to administer as the drops. Dr. Jonas Salk’s original polio vaccine, which effectively rid the United States of the feared virus in the 1950s and 1960s, used a “killed” polio virus but had to be injected.

It looks like “magic mushrooms” send users on a Long Trip — a long, largely pleasant trip:

“Most of the volunteers looked back on their experience up to 14 months later and rated it as the most, or one of the five most, personally meaningful and spiritually significant of their lives,” comparing it with the birth of a child or the death of a parent, says neuroscientist Roland Griffiths of Johns Hopkins University School of Medicine, who lead the research. “It’s one thing to have a dramatic experience you say is impressive. It’s another thing to say you consider it as meaningful 14 months later. There’s something about the saliency of these experiences that’s stunning.”

Griffiths gave 36 specially screened volunteers psilocybin, the active ingredient in so-called magic mushrooms. The compound is believed to affect perception and cognition by acting on the same receptors in the brain that respond to serotonin, a neurotransmitting chemical tied to mood.

Afterward, about two thirds of the group reported having a “full mystical experience,” characterized by a feeling of “oneness” with the universe. When Griffiths asked them how they were doing 14 months later, the same proportion gave the experience high marks for transcendental satisfaction, and credited it with increasing their well-being since then.

But is a lasting, false sense of profundity a good thing?

Helminthic therapy doesn’t sound terribly creepy — until you realize what a helminth is:

In 2004, David Pritchard applied a dressing to his arm that was crawling with pin-size hookworm larvae, like maggots on the surface of meat. He left the wrap on for several days to make sure that the squirming freeloaders would infiltrate his system.

“The itch when they cross through your skin is indescribable,” he said. “My wife was a bit nervous about the whole thing.”

Hookworms kill 65,000 people a year and afflicts hundreds of thousands with anemia, but by suppressing the immune system they can reduce allergy symptoms:

In the late 1980s, the Wellcome Trust issued a grant, and Dr. Pritchard and his Nottingham team set up camp on Karkar Island, Papua New Guinea.

“We didn’t speak the language, and we were sparsely equipped,” he recalled. “But we established a rapport with the people. We gave them worm tablets and would ask them politely, in pidgin English, to collect their fecal matter in buckets for us.”

Hookworm infiltrates a victim’s system when the larvae, hatched from eggs in infected people’s excrement, penetrate the skin, often through the soles of the feet. From there, they enter the bloodstream, travel to the heart and lungs, and are swallowed when they reach the pharynx. They mature into adults once they reach the small intestine, where they can subsist for years by latching onto the intestinal wall and siphoning off blood. After sieving the fecal samples to extract hookworms eliminated when the worm treatment pill was given, the team reached an intriguing conclusion: Villagers with the highest levels of allergy-related antibodies in their blood had the smallest and least fertile parasites, indicating that these antibodies conferred a degree of protection against parasite infection.

And the hookworms seemed equipped to retaliate. After colonizing a digestive tract, the host often showed signs of a blunted immune response, leading Dr. Pritchard to suspect that the worms were reducing the potency of the body’s defenses to make their environment more hospitable.

“Sitting in the jungle for long periods gives you time to think,” he noted. “And this led to the idea that worm burdens of tolerable intensity could be beneficial under some circumstances.”

He began considering a left-field possibility. What if he could round up allergy sufferers, give them worms and see whether their wheezing and watery eyes disappeared?

Nearly 20 years later, his musing began to come to fruition. After Dr. Pritchard’s self-infection experiment, the National Health Services ethics committee let him conduct a study in 2006 with 30 participants, 15 of whom received 10 hookworms each. Tests showed that after six weeks, the T-cells of the 15 worm recipients began to produce lower levels of chemicals associated with inflammatory response, indicating that their immune systems were more suppressed than those of the 15 placebo recipients. Despite playing host to small numbers of parasites, worm recipients reported little discomfort.

Trial participants raved about their allergy symptoms disappearing. Word about the study soon appeared online among chronic allergy sufferers, and a Yahoo group on “helminthic therapy” sprung up.

“Many of the people who were given a placebo have requested worms, and many of the people with worms have elected to keep them,” Dr. Pritchard said.