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Our World Transcript — 14 October 2006


This transcript is provided as a service; there may be some variation between it and the program as broadcast.

MUSIC: "Our World" theme

Straight ahead on "Our World" ... safer atomic power plants ... a fast new test for tuberculosis ... and the bleeding edge of medicine.

ELLIS-BEHNKE: "And when we saw that we thought: Oh, whenever you do neurosurgery at all in the brain and all the bleeding stops, you are concerned that the animal has died because that is typically the only cause for the bleeding to stop that quickly."

Stop the bleeding NOW, natural disaster hotspots, and more. I'm Art Chimes. Welcome to VOA's science and technology magazine, "Our World."

Researchers have developed a new tuberculosis test that makes a diagnosis possible in a fraction of the time it can take using other methods. Experts say the test would be especially useful in the developing world, where the potentially fatal lung ailment is most common. VOA's Jessica Berman reports.

BERMAN: Each year, almost two million people worldwide die of tuberculosis, which is curable with proper treatment.

Researchers have been sounding the alarm recently about a resurgence of tuberculosis, especially drug-resistant strains of the disease.

The new test allows for a diagnosis in just seven days, and, it also determines whether the particular strain of tuberculosis will respond to drug treatment.

Dr. David Moore is with the Wellcome Trust Center for Clinical Tropical Medicine at Imperial College in London. He says the test that is currently most often used in the developing world, called the Lowenstein-Jensen test, takes almost a month to yield results.

MOORE: "It is often very difficult to find that patient a month later. They tend not to come back. So, the clinical utility of a test that takes a month to get a result back is much diminished. In contrast, if you can have a result that takes a week, generally, it is easier to find those patients."

BERMAN: In conventional testing, it takes weeks to get a result because the bacteria from sputum coughed up by those suspected of having tuberculosis are grown in a sugary culture, and technicians make a determination by measuring the amount of carbon dioxide that is produced by the micro-organisms.

The new test also coaxes the TB bacteria to grow using a culture mixture, or broth. However, researchers discovered that when they examined small samples under a microscope, they could see the formation of what they call characteristic tangles in positive TB specimens. The samples are placed in tiny wells in microscope slides. Dr. Moore explains.

MOORE: "We examine that broth under an inverted light microscope \to detect the characteristic growth tangles of the organism mycobacterium tuberculosis in the broth. And by adding TB drugs to some of the wells in which the broth has been inoculated, but not to all of them, can determine whether the organism is resistant to the drugs."

BERMAN: Moore says, bacteria that grow in the absence of antibiotics and stop growing when exposed to the drugs, are not resistant to treatment. But if the TB micro-organism grows, despite the antibiotics, it is resistant to treatment.

Moore led a field trial of the new test in Peru that found that, in every measure, including speed of detection, accuracy and detection of multi-drug resistant strains of TB, the test outperformed Lowenstein-Jensen and the automated detection test used in the West.

The study is published in the New England Journal of Medicine.

ISEMAN: "This method not only reduces the time from conventional third world testing, it is faster than any method used in the industrialized world today."

BERMAN: Dr. Michael Iseman is a specialist of pulmonary diseases at the National Jewish Medical and Research Center in Denver, Colorado.

ISEMAN: "I have done a lot of consulting in the developing world about tuberculosis. And all of us who do this have been frustrated at the inability to do drug cultures, and to do drug susceptibility testing. So in one swoop, this method has the ability to address those big problems."

BERMAN: But it may be a little while before the new test becomes the new "gold standard" TB test.

Iseman writes in his commentary in the New England Journal, there are concerns that not all tuberculosis strains may show the characteristic "tangles" under the microscope. And the new TB cultivation method could present bio-safety hazards that need to be addressed. Jessica Berman, VOA News, Washington.

The United States has a number of national laboratories scattered around the country. In a moment we'll hear about how scientists at one of them are working on safer nuclear power plants. But first ... the first national lab. Argonne National Laboratory, outside Chicago, emerged 60 years ago from the labs that did early nuclear experiments at the University of Chicago, part of the super-secret Manhattan Project that developed the atomic bomb in the 1940s.

Today, Argonne has widened its focus, turning its expertise to other fields, including providing facilities for pharmaceutical researchers.

Until fairly recently, drug makers used a sophisticated trial-and-error method to develop new medicines. But Argonne director Robert Rosner says there's now a better way.

ROSNER: "Today the idea is to look at the agents that cause disease, whether it's a microscopic bug or it's a particular chemical, try to understand the molecular structure of that disease agent, to understand how that disease agent actually makes us sick, and then figure out what you need to insert on the atomic scale to make that disease agent stop functioning. So the idea is basically kind of a lock-and-key mechanism."

To do that, scientists can use Argonne's Advanced Photon Source, the most powerful X-ray machine in the Americas. This isn't like the one in your dentist's office. Instead, it allows researchers to learn more about how molecules look at the atomic level and then, to use Rosner's metaphor, design medicines that prevent the disease key from turning the lock.

The Advanced Photon Source came online a decade ago, and one of its first targets was HIV, the virus that causes AIDS, and that work led to the development of a top AIDS drug called Kaletra.

ROSNER: "It's one of the leading anti-AIDS drugs in the world today that was developed exactly the way I just described, by going to the Advanced Photon Source, which is an X-Ray source that allows you to look at the AIDS virus on the atomic scale and understand its functioning, and Kaletra was then designed to interfere with the functioning."

Robert Rosner of Argonne National Laboratory, which is celebrating its 60th anniversary.

At another national laboratory, researchers are working on safer ways to generate electricity from nuclear power.

The rising price of oil, growing demand for electricity, and concerns about climate change are fueling a renewed interest in atomic power.

Nuclear remains strong in many countries, but here in America only one-fifth of our electricity comes from nuclear plants. It's been almost three decades since a new nuclear power plant was licensed in the United States. The near-catastrophe at Pennsylvania's Three Mile Island plant in 1979 and the deadly accident at Chernobyl seven years later didn't help.

But new technologies are being developed that could ease concerns about safety and disposal of radioactive waste. VOA's Adam Phillips begins with an explanation of the principles of turning nuclear energy into electricity.

PHILLIPS: At the core of every nuclear power plant is a nuclear reactor, where a dense chemical element — usually a uranium ore — is contained within fuel rods. Tiny subatomic particles called neutrons are shot into the uranium, which breaks apart into smaller particles, releasing huge stores of energy in the form of heat.

That heat is absorbed by a cooling agent, usually water, that's constantly circulated around the fuel rods. The super-heated water turns to steam, which drive electromagnetic turbines, which in turn generate the electricity we use in everyday life. And while that process may be simple, it is one in which many things can go - and occasionally have gone - terribly wrong, putting the reactor, its operators, and nearby populations - at great risk.

McCARTHY: "One of the things we're looking at in this new generation of reactors is making them what we call 'naturally safe' [by] relying on things like gravity."

PHILLIPS: Kathy McCarthy is the director of advanced nuclear energy systems integration at the Idaho National Laboratory, a large federal nuclear research facility. The "naturally safe" reactors McCarthy refers to are often called "Generation Four" reactors. They incorporate significant safety improvements over older reactors that use mechanical pumps to circulate their coolant.

In case of a mechanical or power failure in existing plants, the water in stops circulating but the nuclear reactions continue, potentially causing a meltdown or an explosion where radioactive material could be released. The new reactors, says McCarthy, are designed without need of mechanical pumps, so that the convection produced by the fuel rods' great heat keeps the coolant water moving.

McCARTHY: "Heat rises. And so if you lose the mechanical pump, you actually can still get this natural circulation."

PHILLIPS: In the United States, nuclear power plants are a controversial source of energy. But McCarthy contends that every other energy source also has some potential adverse environmental impact…

McCARTHY: "… And you have to be able to deal with that impact. With nuclear, what we have to deal with is our waste — if you want to call it waste — or the used fuel, is all right there. It doesn't go into the sky. There aren't particulates. There aren't emissions. So we have the opportunity to deal with that waste. Now, it is highly radioactive…"

PHILLIPS: … Meaning it emits and gamma rays and neutrons than can penetrate cells and change their structure, causing radiation sickness, cancer and other diseases. And nuclear fuel can remain radioactive for tens of thousands of years.

McCARTHY: "So we need to be able to control that. And we can do that with something called 'shielding.'"

PHILLIPS: In most cases, that means storing the used fuel. In the past, metal canisters for that fuel were designed for short-term use and were subject to rust, or sometimes placed in unstable locations where radioactive waste could potentially leak into the environment.

Today, nuclear fuel storage technology — including a technique for encasing the fuel in solid glass - is designed for the very long term. A proposal is being considered to store used material inside a mountain in the Nevada desert, far from present-day human populations. Another promising approach is to vastly reduce the amount of radioactivity in the fuel that is stored by recycling what comes out of the reactor more efficiently.

McCARTHY: "Because that fuel is not waste. It actually has a significant energy value. We use less than one percent of the energy content of he original ore. So there is a vast amount of energy we haven't tapped into. So we can take that material, put it back into a reactor, cause it to fission, to break it apart and reduce the radioactivity. So we have ways not only to get the energy value from the fuel, but to use it safely. And that's what we're looking at."

PHILLIPS: The American nuclear industry once used reprocessed fuel extensively, but President Jimmy Carter ended the practice back in the 1970s as a way to limit the possibility that plutonium rich material could end up in the wrong hands.

McCARTHY: "Basically you don't want people to take material and make weapons out of it. We're looking at processes that never separate plutonium by itself. So it makes it much less easy to take the material and use it for non-peaceful purposes."

PHILLIPS: Kathy McCarthy is director of advanced nuclear energy systems integration at the Idaho National Laboratory, For Our World, I'm Adam Phillips, in Idaho Falls, Idaho.

The shadow of Chernobyl still hangs over the nuclear power industry.

In Ukraine, they're planning a new containment facility for the remains of the infamous nuclear power plant, where more than half a million fire fighters, military personnel, construction workers and others known as 'liquidators' were exposed to radiation as they dealt with the 1986 accident and its aftermath.

Now, the containment structure built two decades ago needs to be replaced, and workers will again be exposed to higher-than-normal levels of radiation.

Scientists from Duke University in North Carolina say the construction project provides a unique opportunity to study the effects of radiation. Dr. Geoffrey Ginsburg, who heads Duke's Institute for Genome Sciences and Policy, co-authored an article in the journal Science proposing the study.

GINSBURG: "With the current plans to reshelter the Chernobyl nuclear power plant, we now have perhaps a once-in-a-lifetime — or hopefully once-in-a-lifetime — opportunity to look at individuals who are potentially risking exposure to low levels of radiation voluntarily, having signed up to work on this project, and be able to follow them in a long-term fashion to ensure that we can capture the appropriate data that will tell us about the potential risks and dangers, if any, of long-term, low-level radiation exposure."

Ginsburg says it may be possible to test for radiation-induced changes in workers' DNA, not just see if they develop cancer or other diseases.

GINSBURG: "There are a number of ways to measure genetic changes, and we can essentially look at anything from perhaps changes in the DNA itself, as well as to some of the gene products — proteins and RNA [which] can give quite valuable information about exposures and about risks of disease, and certainly that's been borne out in a number of different areas of medicine. It's just that we've never had the opportunity to really look comprehensively at the effects of ionizing radiation."

A study like this would have to last decades and cost a lot of money. But Geoffrey Ginsburg says the countries that are spending as much as a billion dollars to safely entomb the Chernobyl site should be willing to support a study that will provide a vast amount of information about radiation's effect on living beings.

Time again for our Website of the Week, when we showcase interesting and innovative online destinations. This time, it's a virtual encyclopedia, an online resource for all kinds of information about plants and animals, the National Biological Information Infrastructure, at NBII.gov.

KASE: "NBII.gov is something that you could think of as a website, but that would be to seriously underrate it. I think of NBII as more of a global initiative with a lot of people who are cooperatively using technology to use ways to address natural resource challenges around the world."

That's NBII program manager Kate Kase. The scope of NBII is vast. Information about fisheries. Resources for teachers. An image library. And exhaustive coverage of issues such as biodiversity, the health of coral reefs, and bird migration.

KASE: "We have data and information from a lot of different organizations regarding the migratory species themselves, the migratory routest that they take, impediments to migration, and tools that you can use — for example, a geographic interface that allows you to take data layers from different sources and put them on a map, so that you can see how different factors interact with each other."

Much of the information is specific to the United States, but there is a lot of material that transcends national boundaries, such as the section that Annie Simpson manages on invasive species.

SIMPSON: "They cause great harm ecologically, economically, or even to human health. So NBII is emphasizing this because it's so important in many different places - around the world and around the nation."

There's a lot more biology to discover at the National Biological Information Infrastructure website at NBII.gov, or get the link from our site, voanews.com/ourworld.

MUSIC: Herb Alpert & The Tijuana Brass — "Talk To The Animals"

And you're listening to VOA's bio-active science and technology magazine, Our World. I'm Art Chimes in Washington.

The World Bank this week urged better planning to reduce the impact of natural disasters.

A report on natural disaster hotspots was released — and a companion website launched — on Wednesday, which the United Nations observed as the International Day for Natural Disaster Reduction.

Natural disasters may not be preventable, but steps can be taken to reduce the consequences, for example by moving housing away from areas prone to landslides, and strengthening or re-routing pipelines in earthquake zones.

The World Bank report says that 90,000 people died last year as a result of floods, earthquakes and other natural phenomena, and that the financial toll was almost $160 billion.

World Bank vice president Kathy Sierra said there are a number of reasons for the surge in disaster-related calamities and casualties, including increasing urbanization and climate change.

SIERRA: "These are intensifying vulnerabilities that had been in place before but are really causing, when something happens, when a disaster strikes, more people are likely to be affected, more economic losses are likely to be impacted."

Along with its printed report on natural disaster hotspots, the World Bank simultaneously launched a website that uses GIS, or Geographic Information System technology, to map out areas subject to six kinds of natural disasters: cyclones, drought, earthquakes, floods, landslides and volcanoes.

Plotting disaster zones on a map is a powerful tool to help planners develop ways of mitigating the damage before disaster strikes. One of the case studies in the World Bank report is Caracas, Venezuela, where co-editor Arthur Lerner-Lam says they identified numerous risks.

LERNER-LAM: "We looked at water supply infrastructure, and what you see here in the red rectangle, in the trapezoid down below, are areas where the water infrastructure crosses known active faults that could produce earthquakes that would, of course, damage the infrastructure. So those are particular areas of vulnerability that we would like to look at."

You can learn more about natural disaster hotspots and see the risks facing your area on the World Bank website at worldbank.org/hazards, or we have a link on our site, voanews.com/ourworld.

Finally this week, a new approach to stopping bleeding, which could improve survival rates on the battlefield or in the operating room. VOA's Rosanne Skirble reports.

SKIRBLE: Neuroscientist Rutledge Ellis-Behnke made a curious discovery last March while he and researchers from the Massachusetts Institute of Technology operated on the severed brain of a hamster. The liquid material they applied to the wound stopped bleeding in seconds.

ELLIS-BEHNKE: "And when we saw that we thought: Oh, whenever you do neurosurgery at all in the brain and all the bleeding stops, you are concerned that the animal has died because that is typically the only cause for the bleeding to stop that quickly."

SKIRBLE: The animal wasn't dead. Its wound healed, which prompted the scientists to do more experiments.

ELLIS-BEHNKE: "We tested it in the brain, the liver, the muscle, spinal cord, liver and skin punch to look to see if it would work for skin as well and what we found was that the tissue healed completely normally and the material completely disappeared within three to four weeks, depend ing on the concentration of it."

SKIRBLE: The novel therapy stopped bleeding without such conventional means as use of pressure, cauterization or adhesives. Instead, the material itself — comprised of tiny protein fragments — self-assembled into fibers when applied as a liquid to a tissue in a salty environment like blood.

Ellis-Behnke says the process is not clotting but more a knitting or weaving of the cells.

ELLIS-BEHNKE: "And when you look at some of the other hemostatic agents out there, they are not designed to allow the tissue to reconstitute itself. They are designed to just stop bleeding."

SKIRBLE: Ellis-Behnke says the body looks at the reconstituted patch as if it were normal tissue.

ELLIS-BEHNKE: "We're not sure if it is just a physical patch or it's a completely new way to stop bleeding. We are still trying to understand that."

SKIRBLE: Ellis Behnke and colleagues have already initiated tests in larger mammals with hopes to begin human trials within a few years. Ellis-Behnke says the material could be of great value for surgery done in messy environments like a battlefield. The study was published this week in the online edition of the journal Nanomedicine. I'm Rosanne Skirble.

MUSIC: "Our World" theme

That's our show for this week. If you'd like to get in touch, email us at ourworld@voanews.com. Or use the postal address -

Our World
Voice of America
Washington, DC 20237 USA.

Faith Lapidus edited the program this week. Eva Nenicka is the technical director. And this is Art Chimes, inviting you to join us online at voanews.com/ourworld or on your radio next Saturday and Sunday as we check out the latest in science and technology...in Our World.

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