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This week on Our World: Chemists finding inspiration in nature ... vaccination without the — ouch! — without the needle ... and plant known for one deadly product used to create a life-saving one.
ARNTZEN: "Tobacco farmers have been just superb in getting beautiful, succulent plants, and we take all that technology that they've got and apply it to a pharmaceutical product."
Those stories, the scientists behind the Smithsonian, and more.
I'm Art Chimes. Welcome to VOA's science and technology magazine, "Our World."
Chemists Seek Inspiration from Nature
The American Chemical Society held its semi-annual meeting in Washington this week. With some 14,000 participants, it's one of the biggest events on the calendar of scientific conferences, so this week and next we'll be looking at some of the interesting research presented there.
We start with three scientists who are taking their inspiration from the natural world.
Russell Stewart of the University of Utah thinks surgeons could learn a thing or two from a little worm that lives in the Pacific ocean, just off the California coast.
STEWART: "The same problems that a surgeon has that would want to glue bones together in open surgery is very similar to the problems that this sandcastle worm faces when it's gluing sand castles together under water."
Sandcastle worms built a little enclosure for themselves — their sand castle — by collecting bits of sand and shell fragments, and gluing them together with an adhesive they secrete. Stewart says the underwater environment is like what surgeons work with in the body. Most glues don't work unless the pieces you're trying to glue together are dry, so Stewart has been trying to tease out the chemical secret of the sandcastle worm's glue.
STEWART: "In some sense, this worm literally glues skeletons back together under water when they collect seashells and stuff, right? They're exoskeletons, but it's biogenic minerals. And so this glue has been adapted through probably hundreds of millions of years for adhering wet biogenic minerals under water."
After more-or-less copying the chemical makeup of the sandcastle worm's glue, Stewart says they got an artificial copy that worked, but he admits some major challenges remain before the product shows up in your local hospital. For example, if doctors glue pieces of broken bone together, they want the adhesive to dissolve as it is replaced by natural bone.
STEWART: "We want it to degrade, and we need to tune the degradation rates to be appropriate. We'd like them to be roughly the same as the natural healing process, so I think those are going to be bigger problems than we've faced so far."
Russell Stewart of the University of Utah says it's unlikely his surgical glue, if perfected, will replace plaster casts for broken arms or legs. But he says for more delicate, non-weight bearing repairs - like the bones of a face smashed up in an auto accident — a surgical glue could be just what the doctor ordered.
Pesticides are a big business worldwide, as farmers use chemicals on their crops to maximize their harvest.
But there's increasing concern about the safety of those products, many of which are neurotoxins that can harm humans as well as insects. It's one reason why organic food is one of the fastest growing segments of the U.S. grocery market.
Some plants have evolved their own pesticides, and some scientists are at work harnessing those natural bug killers. It's a concept with a long history, says Murray Isman of the University of British Columbia.
ISMAN: "The use of plants for protecting stored grains, stored lentils, has been practiced for centuries or longer in many parts of the Mediterranean, North Africa, Southeast Asia, China, and really as I said, it's the rediscovery of many of these plants and the fact that they do have good biological properties, that has led to the use of some of these more recent, natural product-based pest controls."
The Canadian scientist has been working on products based on the chemistry of natural pesticides from plants, including rosemary and clove, to name just a couple.
While he doesn't expect plant-based pesticides to completely replace conventional products, he says they do have some significant advantages, notably safety.
ISMAN: "You can spray them in the morning and harvest your crop in the afternoon because there's no concern about residues on agricultural commodities. So wherever there's a premium on human safety and exposure, these are good products."
The active ingredients are volatile oils, meaning they evaporate quickly. That's a disadvantage if you need a product that keeps working over a long period of time.
Isman is working with a U.S. company to develop commercial versions of these plant-based pesticides, but he says a low-tech approach might also work in developing countries, where many of the plants are grown. One of his graduate students, from Indonesia, turned her attention to a common tropical plant, the soursop tree, whose bitter seeds contain a natural insecticide.
ISMAN: "And she was able to grind up the seeds with a little bit of dish soap and water, and make a very crude preparation that we showed, at least in greenhouse trials, was very effective in controlling several insect pests. So she was hoping to take that very crude technology back to eastern Indonesia and try to develop a cottage industry around producing this thing, at least for local agriculture.
Murray Isman of the University of British Columbia.
Kudzu-Based Chemicals May Treat Alcoholism
Canada — and the rest of the northern hemisphere — is heading into the influenza season, and even without the additional threat of H1N1 swine flu, this is the time when millions of doses of flu vaccine are being manufactured ... in chicken eggs. It seems an odd way to make a high tech product, but it's the best way the pharmaceutical industry has found to produce the vaccine, at least so far.
Discovering a vaccine is just one part of preventing or treating a disease. Mass producing it is just as important, and scientists at this week's American Chemical Society meeting described how a vaccine can be made in plants, ordinary tobacco plants to be specific, by infecting the tobacco with a genetically modified virus.
ARNTZEN: "Within 5-10 days that virus takes over the host plant and starts producing whatever protein you want. So within 2 weeks, you can isolate enough material so that you can make a full dose of vaccine for anywhere from thousands to possibly millions of people."
Charles Arntzen of Arizona State University has been working on a vaccine to combat norovirus, a fast-spreading bug that is sometimes called the "cruise ship virus" because it is particularly active in close quarters like a ship. It causes nasty gastrointestinal symptoms for a couple of days, but rarely has long-lasting consequences.
Arntzen stresses that his norovirus vaccine does not use genetically modified tobacco plants.
ARNTZEN: "One of the savings in cost is, we grow up a greenhouse full of absolutely normal plants, we don't have to do any special containment or anything else. The only genetic modification is to the virus that we use to infect the plant, and that's done in an enclosed facility."
CHIMES: Why tobacco plants in particular?
ARNTZEN: "We've chose to use tobacco as our host plant primarily because of its large biomass. Tobacco farmers have been just superb in getting beautiful, succulent plants, and we take all that technology that they've got and apply it to a pharmaceutical product."
CHIMES; Do you see the irony in using a plant like tobacco?
ARNTZEN: (chuckles) "I guess there is some irony involved, yes, but much maligned as tobacco is, if we get the first cancer vaccine for non-Hodgkin's lymphoma out of tobacco, it'll be a payback in some way."
The German company Bayer, in fact, is developing a vaccine for non-Hodgkin's lymphoma. It would be a so-called therapeutic vaccine — designed to treat the disease, not to prevent it in the first place. And each dose would be tailored to the individual patient, which is why the fast turnaround of plant production is ideal.
An influenza vaccine produced in plants is also under development, this one by a Canadian company.
None of these vaccines are on the market yet, and won't be for several years at least, because of the regulatory process.
Kudzu-Based Chemicals May Treat Alcoholism
And another plant with an unsavory reputation has inspired another scientist. VOA's Steve Baragona reports on how chemicals from an Asian weed are being used as treatment for alcohol dependence.
BARAGONA: Drive through the countryside anywhere in the southern United States and you're likely to see vines of kudzu smothering trees, shrubs, telephone poles, old cars, and anything else in their path.
Americans consider it an invasive weed, but in Asia, where it originated, parts of the plant have been used for centuries to treat alcohol dependence.
Some U.S. herbal remedy shops sell kudzu extracts. The problem is, the compounds that seem to be responsible for kudzu's alcoholism-fighting effects aren't absorbed in the body very well; and researchers have found the preparations in health food stores often don't contain much of it, anyway.
Ivan Diamond is an alcoholism researcher at the University of California, San Francisco. He and his colleagues took a different approach.
DIAMOND: "So instead of using the natural compound, we made a better synthetic compound, which we know would get absorbed and work better in the body and be more effective."
BARAGONA: Working at a startup pharmaceutical company that's now part of Gilead Sciences, Diamond and his colleagues tested this compound on lab rats and found it decreased their desire to drink alcohol. That wasn't surprising. The compound works the same way as another drug already on the market that interferes with the body's system for breaking down alcohol. People who take that drug feel sick when they drink, Diamond says.
DIAMOND: "The thought is, if you get sick when you drink, then you won't drink. But what happens to most people is that they don't have the motivation to really stop. They still have the desire and the craving to drink. So they just stop taking the medicine and they go back to drinking."
BARAGONA: Like getting rid of kudzu, Diamond says you have to attack the roots. The key to beating alcohol dependence is to control the craving to drink.
And those cravings are rooted in a specific part of the brain that's activated whenever we feel pleasure, he says.
DIAMOND: "All addicting drugs activate that part of the brain. And a key player in the response to alcohol and addicting drugs is an increase in dopamine in that brain region.
BARAGONA: So lowering the levels of that brain chemical dopamine should help control an alcoholic's cravings.
Diamond's new drug did lower dopamine levels in lab rats. And rats given the drug weren't willing to press a lever as many times to try to get a drink — the closest model scientists have to measuring rats' alcohol cravings.
But promising as it is for rats, it remains to be seen whether the drug is safe and effective for people. In the meantime, a new quality-controlled herbal kudzu extract will probably reach the market sooner, since herbal remedies don't need approval from the government. The kudzu extract reduced alcohol consumption in people who took it, but its effect on alcohol cravings wasn't tested. So it's not clear if this kudzu treatment attacks the roots of alcohol dependence, or just stems the drinking. Diamond's research is published in the November issue of the journal Alcoholism: Clinical & Experimental Research.
Steve Baragona, VOA News, Washington
Smithsonian Spotlights Research on the Website of the Week
It's time again for our Website of the Week, when we showcase interesting and innovative online destinations.
Visitors to Washington almost always stop at at least one of the many museums of the Smithsonian Institution, with collections showcasing space exploration, American history, nature, and the arts. Far fewer people know about the Smithsonian's important research work, which takes place behind the scenes.
But at SmithsonianScience.org, you can take an over-the-shoulder look at top scientists at work.
BARRAT: "Science plays a critical role in the daily life of the institution. We do science every day, exploring the nature and the origin of the universe, the formation and evolution of the Earth and the other planets, understanding the biological diversity of life on Earth, and human diversity and cultural change."
John Barrat is a writer-editor at the Smithsonian. SmithsonianScience.org is full of interesting articles and multimedia about the discovery of new bat species in the museum's collection or the birth of new animals at the zoo, or evidence of prehistoric global warming. Some scientists work at Smithsonian museums, while others work at specialized research centers.
BARRAT: "One of our oldest research institutions is the Smithsonian Astrophysical Observatory. They are monitoring the movements of glaciers in Greenland. More recently they measured the Milky Way galaxy and learned that it's larger and more massive than they previously realized."
There's also a growing series of videos of scientists describing their work.
SCHNITZER: "My name is Stefan Schnitzer. I am a research associate at the Smithsonian Tropical Research Institute in Panama. ...."
The site is just a few months old, and more content is constantly being added, on SmithsonianScience.org, or get the link to this and more than 250 other Websites of the Week from our site, VOAnews.com/ourworld.
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It's Our World, the weekly science and technology magazine from VOA News. I'm Art Chimes in Washington.
Sleep Apnea Can Shorten Life, Research Indicates
Many people snore… and keep their family members awake. But snoring has other risks associated with it, other than lost sleep. Researchers now believe severe snoring can actually shorten life. Rose Hoban has more.
HOBAN: Snoring is something more than just a loud annoyance. Severe snoring is often a sign of sleep apnea. Professor Dan Gottlieb from Boston University studies the phenomenon.
GOTTLIEB: "Some of the other signs that suggest that you do have sleep apnea is if a bed partner tells you that you stop breathing during sleep, or you look like you're struggling to breathe at nights, or if despite a good night of sleep — seven or eight hours of sleep — you still feel unrested upon awakening."
HOBAN: As many as one in seven adults have at least mild obstructive sleep apnea, and perhaps one in 25 has a severe form of the condition.
Over the course of more than a decade, Gottlieb and his colleagues recruited more than 6,000 men and women over the age of 40 and asked them to undergo an overnight sleep evaluation. Then they followed these subjects for years.
GOTTLIEB: "What we found was that individuals who had a severe obstructive sleep apnea overall had about a 50 percent higher risk of dying during the follow-up period which was an average of just over eight years. And this was particularly strong for participants who, at the start of the study, were under 70 years of age and whom the risk of dying during follow-up was approximately twice as great as those who did not have sleep apnea."
HOBAN: Gottlieb says this outcome was true no matter whether or not the person had heart disease, diabetes, or other medical conditions. Sleep apnea was responsible for people living shorter lives.
Gottlieb says one of the biggest risk factors for obstructive sleep apnea is being overweight.
GOTTLIEB: "So the more overweight a person is the more likely they are to have sleep apnea. Men, all other things being equal, are about twice as likely as women to have sleep apnea, although it does occur in women as well."
HOBAN: Overweight or obese people can improve their sleep, Gottlieb says, by losing weight, exercising and avoiding alcohol before bedtime. He also says the easiest way to reduce snoring is to sleep on one's side.
The sleep apnea paper is published in the online journal PLoS Medicine.
I'm Rose Hoban.
Researchers Develop Dry Vaccination Methods for Measles
Medicines or vaccines sometimes have to be given as an injection, and I don't know anyone who likes getting a shot. No matter what they say, it can hurt! But even worse, there's the risk of contamination or infection if the needle is reused or not disposed of properly. So there's plenty of interest in finding other ways to get medicine into patients.
Reporter Véronique LaCapra spoke with a researcher who is working to develop an alternative to liquid vaccine injections.
SIEVERS: "The purpose of our research was to try to find ways to deliver vaccines without using needles."
LaCAPRA: Bob Sievers is a chemistry professor at the University of Colorado in Boulder, and the head of a small chemical company called Aktiv-Dry. With a grant from the Bill and Melinda Gates Foundation, Sievers is developing a dry powder form of the measles vaccine that would be inhaled, instead of injected.
SIEVERS: "The first advantage to the patient of course is it doesn't hurt, there's no pain associated with inhaling an aerosol, like there is with getting a needle-stick."
LaCAPRA: Since an inhalable vaccine would eliminate the need for injection, vaccine recipients would not risk getting infected by reused needles. Health care providers would be safe from accidental needle-sticks, and there would be no contaminated needles to dispose of.
SIEVERS: "You can step on a used needle that's thrown out in the trash dump, and contract hepatitis B or something else that would really be only because you had used needles in delivering the vaccine for measles."
LaCAPRA: Another problem with the liquid vaccine is that once it's mixed, it must be used within six hours. That's not the case with Sievers' inhalable version.
SIEVERS: "You can keep it for two years, as a dry powder."
LaCAPRA: Sievers says his team has also worked hard to keep down the cost of their vaccine.
SIEVERS: "It will not cost any more than the version that you use today with a needle."
LaCAPRA: Animal studies have shown the new vaccine is both safe and effective at preventing measles infection. Sievers plans to begin human clinical trials in India in 2010. If all goes well, he says the inhalable dry powder measles vaccine could be available for use in two to four years.
And he adds that in the future, the same method could be used to create inhalable dry powder versions of other vaccines and medications.
Sievers spoke about his work this week at the annual meeting of the American Chemical Society, where he was presented with an Astellas Award for his significant contribution to improving public health.
Véronique LaCapra, for VOA News, Washington.
Like many big conferences, the American Chemical Society meeting in Washington featured not just presentations, symposiums, and social events for networking, but also an exhibition area full of marketing people with products and services that might be needed by people in the chemistry field.
My name is Mark Flowers, I'm with Nanoscience Instruments
, and we're selling atomic force microscopes. It's an instrument that basically maps the surface of a material down to the nanometer scale, so you get a real 3D image of a surface. You can, in some cases, resolve individual atoms.
I'm Jerry Baranovsky; and the company is Cambridgesoft Corporation
. And we develop chemical and scientific software for the pharmaceutical industry, the chemical industry. We were the developers of Chem Draw. You can type in the name of a compound and it'll draw the whole compound for you.
I'm Gary Weissinger, I'm the business development manager for Miele Incorporated
, professional division. What we manufacture are laboratory glassware washers. It's like a dishwasher on steroids, as I like to say.
My name is Rekha Eastwood from Spectrum Chemicals and Laboratory Products
. We sell a wide variety of chemicals as well as distribute laboratory supplies. We have bulk quantities for production as well as smaller quantities for laboratories.
Greg Cook, Erlab Group
. We're the inventor of the ductless fume hood. A fume hood is a containment device where you do all your chemical procedures so you're not exposed to the chemicals. In layman's terms, it will suck the air away from the user and filter it. A traditional fume hood consumes $8-12,000 worth of energy; this costs under $300 for energy consumption for the year.
Among the many other exhibitors were publishers, government agencies, and even a company selling T-shirts imprinted with science-themed designs, including the Periodic Table of the Elements.
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Our World is edited this week by Faith Lapidus. Bob Doughty is the technical director.
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