Nanotech to improve health care delivery

Nanotech to improve health care delivery – at the molecular scale

Nanotechnology's potential for improving drug delivery, tissue regeneration and laboratory miniaturization is being explored by a diverse array of University of Michigan researchers.

A handful of these leading scientists from engineering, public health, dentistry and medicine discussed the promise of nanotechnology for oral health diagnosis and treatment on a special panel at the AAAS Annual Meeting on Feb. 17.

Drug delivery

To help get the most potent anti-cancer drugs off the shelf and into the clinic, U-M researchers are looking at two nanotechnology approaches to precisely deliver drugs and visualize individual cells.

One system is a star-shaped synthetic molecule called a dendrimer, and the other is a tiny plastic bead called a PEBBLE.

A dendrimer is a star-shaped synthetic molecule that can be as small as three or four nanometers in diameter, about the size of a single molecule of hemoglobin in a red blood cell. That means it is also fine enough to slip through the walls of blood vessels and get inside cells.

James R. Baker Jr. is leading the dendrimer projects as director of the Michigan Nanotechnology Institute for Medicine and Biological Sciences, with support from the National Cancer Institute, NASA, and the Bill and Melinda Gates Foundation.

The ends of a dendrimer's many branching arms can be studded with molecules that bind to specific receptors on the surface of cancer cells. Other arms of the molecule can carry chemicals to mark or even kill the target cells. Injected into the bloodstream, dendrimers converge on cancer cells, then actually enter the cells. There, they deliver the drugs that kill cancer cells. In preliminary animal studies, drugs appear to be 50 to 100 times more effective with this sort of direct delivery, Baker said.

A group led by toxicologist Martin Philbert and biophysicist Raoul Kopelman is working with tiny plastic beads called PEBBLES-probes encapsulated by biologically localized embedding.

Sized at 20 to 600 nanometers, PEBBLES can be coated with targeting molecules and used as a very precise contrast agent for imaging and drug delivery. Once they reach their goal, sound or light can trigger them to carry out their mission. In some cases, the killer agent can be something as simple as reactive oxygen, says Philbert, a professor of toxicology and senior associate dean for research in U-M's School of Public Health.

Though the PEBBLEs group has done work to get the tiny balls inside cells, including using a gene gun that blasts them like little bullets and attaching them to liposomes and letting the body's own fats provide the transportation, Philbert notes that penetration isn't always necessary to get the medical benefits. He says the tiny balls latched on to the outside of selected cells can deliver "killer oxygen" on cue to kill off the cell without penetrating it.

Tissue regeneration

Panel co-organizer David Kohn, professor of biologic and materials science in the U-M Dental School and biomedical engineering in the College of Engineering, studies bone structure at the molecular level. In experiments that use tissue engineering to build bone and other mineralized tissue, Kohn said, "we use a process that's like nature's, but certainly not as elegant."

The nanoscale structure of bone is crucial to its ability to balance strength and light weight, Kohn explains. Many anti-osteoporosis drugs on the market today merely add mineral mass, without doing enough to duplicate the mechanical properties of bone. "Mass alone is not enough to impart fracture resistance," Kohn said. Kohn's recent work is exploring ways to control the mineral composition and structure of new bone.

Laboratory miniaturization: Reconfigurable cell adhesion substrates

A team led by Shuichi Takayama, assistant professor of biomedical engineering, has replicated the nano-scale features and stickiness of cell-adhesion molecules in a laboratory device. Studying how the surface of a cell interacts with adhesion proteins is key to understanding signal transduction, growth, differentiation, motility and cell death. But in vitro models are hard to come by.

Takayama's team has developed a substrate that can be split into parallel cracks and then lined with cell adhesion proteins to study cellular responses. The cracks may be tailored from 120 to 3200 nanometers, making them similar in size to the adhesion surfaces found in nature. The cracks may also be adjusted in situ to study changes in cell behavior. ###

AAAS Annual Meeting Advanced Seminar Oral Nanotechnology: Innovative Strategies for Disease Detection, Diagnosis, and Therapy 8:30 a.m. CST, Friday, Feb. 17.

Links The Future, Writ Small lifesciences.umich.edu/research/featured/

Michigan Nanotechnology Institute for Medicine and Biological Sciences nano.med.umich.edu/

News Media Contacts:
James R. Baker MDRuth Dow Doan Professor of Biologic Nanotechnology, Professor of Internal MedicineDirector, Michigan Nanotechnology Institute for Medicine and Biological SciencesContact: Sally Pobojewski, pobo@umich.edu, (734) 764-2220

David Kohn Ph.D.Professor, Biologic and Materials Sciences and Biomedical Engineering(734) 764-2206 dhkohn@umich.edu

Martin Philbert, Ph.D.Professor of ToxicologySenior Associate Dean For Research, School of Public Health(734) 763-4523 philbert@umich.edu

Shuichi Takayama Ph.D.Assistant Professor of Biomedical Engineering and Macromolecular Science and Engineering(734) 615-5539http://www.eurekalert.org/pub_releases/2006-02/takayama@umich.edu

Contact: Karl Leif Bates batesk@umich.edu 734- 647-1842 University of Michigan

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nano-canary in the nanotoxicology coalmine

New nano-canary in the nanotoxicology coalmine: The body itself

With an eye on disembodied cells and virtual organs, researchers attempt to track biological changes as they occur

There is growing consensus among scientists, regulators, politicians, industry and the public that we need to know more about the possible harmful or adverse effects of nanoparticles on human health.

Likewise, most agree that these incredibly small materials can behave quite differently from conventional materials. Nonetheless, neighborhood stores feature products that promise benefits from these near-atomic level materials, from paints and cosmetics to toothpaste and sunscreens. But, could we be putting human health at risk by exposing consumers to potentially toxic materials?

To investigate the damage potential of sub-micron sized particles, S.K. Sundaram and Thomas J. Weber, scientists at the Department of Energy's Pacific Northwest National Laboratory in Richland, Wash., have harnessed living cells to monitor responses to a variety of biologically active test agents. They presented their findings Friday at the American Association for the Advancement of Science annual meeting.

"Our process requires that live cells be grown on an infrared transparent substrate giving us an opportunity to closely examine the biological effects in living cells," said Sundaram. Live cell Fourier transform infrared, FTIR, spectroscopy offers several attractive features for these investigations. These include the potential to detect biologically active nanoparticles without any prior knowledge of cell signaling pathways affected by them or need of a contrast agent to detect the biological response. Thus, live cell FTIR spectroscopy is expected to be a sentinel of exposure to help identify the physico-chemico properties of nanoparticles that mediate biological activity, without bias of what that biological activity represents.

The PNNL scientists are also developing infrared transparent chemistries that are expected to improve FTIR measurements in live cell experiments. "We believe this report outlines the first use of FTIR spectroscopy to examine the biological response of living cells to nanoparticles, and expect this technology will enable us to identify chemical changes associated with the biological response," said Weber. FTIR spectroscopy measures a broad spectrum of chemical bonds and will provide information that is complementary to genomic and proteomic approaches.

FTIR spectra are captured in minutes in live cell studies, offering a tool to rapidly detect whether nanoparticles are biologically active. This information can be used to prioritize nanoparticles for further study to ascertain the nature of the biological activity in terms of toxicity.

A broader approach underway at PNNL for discovering what environmental nanomaterials can do once they enter the body – and how they enter and where they go – is part of a large collaborative effort funded by NIH, DOE and private industry. This research is aimed at developing predictive respiratory system models for laboratory animals and humans. A key component of this multi-institution collaborative effort is a $10 million, 5-year Bioengineering Research Partnership, BRP, funded by the National Heart Lung and Blood Institute that is designed to devise 3-D imaging and computational models that provide unsurpassed detail of respiratory systems in humans and other mammals.

Advancements in medical imaging, data analysis and computation have increased "the speed and accuracy of developing detailed models of the complete respiratory system," reported Richard Corley, PNNL staff scientist and director of the multi-institutional BRP. "New imaging techniques also show promise for validating particle deposition models. Atlases of airway geometries and functional characteristics are also being constructed to facilitate analyses of variability, reduce uncertainties in animal to human extrapolations and contribute to a more quantitative representation of environment-disease interactions." ###

Pacific Northwest National Laboratory (pnl.gov/) is a DOE Office of Science laboratory that solves complex problems in energy, national security, the environment and life sciences by advancing the understanding of physics, chemistry, biology and computation. PNNL employs 4,100 staff, has an annual budget of more than $700 million annual budget, and has been managed by Ohio-based Battelle since the lab's inception in 1965.

The capability of measuring and modeling subcellular responses to toxicants represents significant progress toward an important capability within PNNL's Environmental Biomarkers Initiative (biomarkers.pnl.gov/). The EBI applies system science and pattern recognition to the discovery of biomolecular signatures. PNNL believes biomarkers provide the next generation of risk assessment tools, replacing whole-organism measures of response with directly measured sub-cellular responses from first exposure through terminal disease state.

Contact: Geoffrey Harvey geoffrey.harvey@pnl.gov 509-372-6083 DOE/Pacific Northwest National Laboratory

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There's something fishy about human brain evolution

There's something fishy about human brain evolution

Forget the textbook story about tool use and language sparking the dramatic evolutionary growth of the human brain. Instead, imagine ancient hominid children chasing frogs. Not for fun, but for food.

According to Dr. Stephen Cunnane it was a rich and secure shore-based diet that fuelled and provided the essential nutrients to make our brains what they are today. Controversially, according to Dr. Cunnane our initial brain boost didn't happen by adaptation, but by exaptation, or chance.

"Anthropologists and evolutionary biologists usually point to things like the rise of language and tool making to explain the massive expansion of early hominid brains. But this is a Catch-22. Something had to start the process of brain expansion and I think it was early humans eating clams, frogs, bird eggs and fish from shoreline environments. This is what created the necessary physiological conditions for explosive brain growth," says Dr. Cunnane, a metabolic physiologist at the University of Sherbrooke in Sherbrooke, Quebec.

The evolutionary growth in hominid brain size remains a mystery and a major point of contention among anthropologists. Our brains weigh roughly twice as much as our similarly sized earliest human relative, Homo habilis two million years ago. The big question is which came first – the bigger brain or the social, linguistic and tool-making skills we associate with it?

But, Dr. Cunnane argues that most anthropologists are ignorant or dismissive of the key missing link to help answer this question: the metabolic constraints that are critical for healthy human brain development today, and for its evolution.

Human brains aren't just comparatively big, they're hungry. The average newborn's brain consumes an amazing 75-per cent of an infant's daily energy needs. According to Dr. Cunnane, to fuel this neural demand, human babies are born with a built-in energy reservoir – that cute baby fat. Human infants are the only primate babies born with excess fat. It accounts for about 14 per cent of their birth weight, similar to that of their brains.

It's this baby fat, says Dr. Cunnane, that provided the physiological winning conditions for hominids' evolutionary brain expansion. And how were hominid babies able to pack on the extra pounds? According to Cunnane their moms were dining on shoreline delicacies like clams and catfish.

"The shores gave us food security and higher nutrient density. My hypothesis is that to permit the brain to start to increase in size, the fittest early humans were those with the fattest infants," says Dr. Cunnane, author of the book Survival of the Fattest, published in 2005.

Unlike the prehistoric savannahs or forests, argues Dr. Cunnane, ancient shoreline environments provided a year-round, accessible and rich food supply. Such an environment was found in the wetlands and river and lake shorelines that dominated east Africa's prehistoric Rift Valley in which early humans evolved.

Dr. Cunnane points to the table scrap fossil evidence collected by his symposium co-organizer Dr. Kathy Stewart from the Canadian Museum of Nature, in Ottawa. Her study of fossil material excavated from numerous Homo habilis sites in eastern Africa revealed a bevy of chewed fish bones, particularly catfish.

More than just filling the larder, shorelines provided essential brain boosting nutrients and minerals that launched Homo sapiens brains past their primate peers, says Dr. Cunnane, the Canada Research Chair in Brain Metabolism and Aging.

Brain development and function requires ample supplies of a particular polyunsaturated fatty acid: docosahexaenoic acid (DHA). DHA is critical to proper neuron function. Human baby fat provides both an energy source for the rapidly growing infant grey matter, and also, says Dr. Cunnane, a greater concentration of DHA per pound than at any other time in life.

Aquatic foods are also rich in iodine, a key brain nutrient. Iodine is present in much lower amounts from terrestrial food sources such as mammals and plants.

It was this combination of abundant shoreline food and the "brain selective nutrients" that sparked the growth of the human brain, he says.

"Initially there wasn't selection for a larger brain," argues Dr. Cunnane. "The genetic possibility was there, but it remained silent until it was catalyzed by this shore-based diet."

Dr. Cunnane acknowledges that for the past 20 years he's been swimming upstream when it comes to convincing anthropologists of his position, especially that initial hominid brain expansion happened by chance rather than adaptation.

But, he says, the evidence of the importance of key shoreline nutrients to brain development is still with us – painfully so. Iodine deficiency is the world's leading nutrient deficiency. It affects more than a 1.5 billion people, mostly in inland areas, and causes sub-optimal brain function. Iodine is legally required to be added to salt in more than 100 countries.

Says Dr. Cunnane: "We've created an artificial shore-based food supply in our salt." ###

Contact: Stephen Cunnane stephen.cunnane@usherbrooke.ca 819-821-1170 Natural Sciences and Engineering Research Council

Arnet Sheppard, NSERC Public Affairs, (613) 859-1269

Dr. Cunnane's AAAS Presentation, Expatiation, Metabolic constraints and Human Brain Evolution, Saturday, February 18, 2006, 8:00 a.m. - 9:30 a.m. Central Time

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Marine mammals are on the frontline of failing ocean health

Diseases may be early warning sign for humans say scientists

Leading scientists, physicians, and veterinarians are uncovering new links between land-based pollution and diseases in marine mammals, with implications for human health.

"Marine mammals are providing early clues of our unseen impact on the sea," says Paul Sandifer, Chief Scientist for the new Oceans and Human Health Initiative in the US National Oceanic and Atmospheric Administration (NOAA). "There is mounting evidence that our activities on land are taking a toll on the health of the oceans, and in turn our own well-being."

"Wildlife can serve as a source of infection, as we have seen with the avian bird flu, but they can also be sentinels of pathogen pollution. They are often the first victims of these diseases," says Pat Conrad from the University of California at Davis. "By paying attention to them, it will tell us about our own health and the links between our health and that of the environment."

Cats and Otters: A Deadly Link to Land? When Pat Conrad first started studying the death of otters on the California coast, she had no idea that her investigation would lead her upstream. Her team traced the cause of death to the brain parasite, Toxoplasma, and ultimately to cats.

"Before I started this project I didn't think about things like how much cat feces gets in to the environment - how what we dump on our lawns and sidewalks flows into streams to rivers and into the ocean," says Conrad.

But with the discovery that otters in areas with heavy freshwater outflow are nearly three times as likely to be infected with Toxoplasma, and the fact that sea otters spend their entire lives grooming, sleeping, eating, and playing in the same nearshore waters where humans swim and surf, this land-sea connection is front and center.

Toxoplasma can also infect humans. It is the third most common cause of death due to food borne disease in the US: estimates indicate that up to 25% of the population may be infected with the parasite, but people rarely show symptoms or are simply hit with a flu-like illness. However, if women are infected when they are pregnant, it can lead to miscarriages or developmental problems in the fetus, most often affecting brain function and sight. Toxoplasma can also cause a severe brain disease in people with suppressed immune systems from transplant surgeries or HIV/AIDS.

"When otters get toxoplasmosis, they get far more sick than most humans," says Conrad. This allows researchers to more easily detect and trace the disease – and calls attention to the flow of pathogens from land to sea that might otherwise go unnoticed.

Conrad recommends that cat owners keep their animals inside and dispose of kitty litter by bagging it up and sending it to a sanitary landfill. "I know this is tough," says Conrad. "I own four cats. I hate cleaning cat boxes, but I know it's in the best interest of the cats, wildlife, and human health."

Not Just Shellfish Poisoning: The Unseen Effects of Red Tides Manatee die-offs are revealing new health impacts of algal blooms - for both manatees and humans.

"Recent, frequent red tides off the west coast of Florida correlated with a 54% increase in emergency room admissions for respiratory illnesses, including, pneumonia, asthma attacks, and other respiratory problems," says Gregory Bossart of the Harbor Branch Oceanographic Institution.

Scientists suspect that these diseases are linked to brevetoxins, compounds produced by specific algal blooms. Neurotoxic shellfish poisoning and other acute effects of consuming brevetoxins are not new to scientists. But Bossart and his colleagues' work on manatee die-offs associated with red tides shows that inhalation of the toxin is also a primary route of exposure. Recent lab work also suggests that long-term, repeated exposure to brevetoxins suppresses respiratory and immune systems, making manatees and other animals more susceptible to new diseases.

"The insidious effect of chronic exposure is what worries me the most," says Bossart. "This infers that you could really open a Pandora's box in these animals, and possibly in humans. Manatees are the 2000 pound canary."

Bossart is also concerned about new data indicating that fish and other food sources - once thought to die too quickly to pass on brevetoxins – can concentrate and carry the toxin long after an algal bloom. "This is surprising," he says. "We never suspected that there could be vectors like seagrass or fish."

Many scientists believe algal blooms are likely caused by multiple stresses, such as nutrient overloading and global warming, acting together. These blooms are on the rise, and many are associated with toxins and bacteria that are harmful to humans. "We need to figure out what is causing this increase," says Bossart. "It's in our own best interest."

Mammals Are What They Eat

Land-based pollutants are so prevalent in the ocean that scientists are using them to trace the diets and travels of marine mammals. This work also sheds light onto potential human health effects of these contaminants.

"Many things we do in modern, industrialized society produce POPs (persistent organic pollutants) - burning of municipal waste, pulp mills, flame retardants, stain repellents – there are all sorts of sources," says Todd O'Hara of the University of Alaska Fairbanks.

In laboratory studies and acute exposure scenarios, persistent organic pollutants have been shown to affect brain function, reproductive success, and the immune system, but there is little information on the impact of chronic, low-level exposure. Animals like killer whales and polar bears, who share many of our marine foods, accumulate these contaminants in their tissues.

Todd O'Hara works with a research team to study the ecological, biochemical, and physiological details of this contaminant build-up in mammal tissues. One piece of their work focuses on how health risks change with different diets. Levels of organohalogens and mercury are higher in animals like polar bears and seals that have fish and marine mammal-based diets, while cadmium (a heavy metal associated with bone and renal disease) is higher in organs of mammals with invertebrate-based diets.

"The issue is to understand how pollutants are transferred through the ocean food web to consumers, both humans and animals," says Peggy Krahn of the NOAA. "Until we understand this, we can't start to say how to mitigate pollutants in the ocean."

Krahn and her colleagues trace the flow of contaminants by studying the build-up of pollutants in killer whales. Different levels and timing of chemical use around the globe create distinct chemical signals that are reflected in the tissues of fish, seals, and other killer whale food. Prey from California waters have a chemical signature that reflects high use of DDT as an agricultural pesticide prior to the US ban in the 1970's. Similarly, chemical ratios that show high levels of flame retardants (PBDEs) are linked to areas near urban runoff and sewage outfalls.

The signal of pollutants is so distinct that it is echoed in the tissues of killer whales. Sub-populations once thought to feed mainly on salmon in Alaska are now suspected to be feeding on high trophic-level fish, such as shark or tuna, in California during the winter. Until recently, information about these animals was based on limited field studies. "This approach allows you to go where mere field observation would fail you," says Krahn. "We're filling in the pieces of a puzzle."

Some suspect that declines of killer whales in Puget Sound may be linked directly to contaminated fish or increased susceptibility to stresses like vessel traffic. Similarly, adverse health effects of PCBs may explain recent observations of pseudo-hermaphroditic polar bears and bears with decreased immune function, but there is no clear evidence that would prove a cause-and-effect relationship. Scientists hope their research will help society proactively evaluate the effects and trade-offs of important pesticides and other chemicals before they cause problems in the environment.

"As old chemicals are taken out of use, new ones pop up," says Krahn. "Often we don't know if the new substitutes will harm the ecosystem."

"It's a struggle to find replacements," says O'Hara. "But wouldn't it be better to know ahead of time if certain policies or practices might be disastrous? We could talk more about prevention rather than trying to fix the damage."

Sea Lions, Herpes, and Cancer

In the past 15 years, 17% of dead and stranded sea lions in California have been diagnosed with a urogenital cancer, similar to cancers we see in humans. Researchers found high levels of persistent organic pollutants (POPs) in these animals and believe contaminants, when combined with specific genetic traits and a herpes virus, are a key factor in causing the cancer.

"We see the herpes virus in sea lions without cancer, so the virus alone isn't enough to cause cancer in sea lions, which is why we think organochlorines (a class of POPs) play a role either directly in the urogenital tract or in suppression of the immune system," says Frances Gulland of The Marine Mammal Center.

"These are top level predators," says Gulland. "Like us, they eat anchovies, squid, salmon, and mussels - they are sentinels for human health because they share our ecosystems and prey. We may see impacts in sea lions before people - they could be an early warning."

Compounding Factors & Climate Change – Alaska as a Laboratory

One of the most challenging aspects of understanding how humans impact ocean health is the fact that so many environmental changes are going on at the same time. Climate change is already having an effect on the spread of disease and pollutants, adding yet another twist to the story.

Jim Berner, an MD with Alaska Native Tribal Health Consortium, works in northern ocean ecosystems, where climate change is having a marked effect. "Alaska is a laboratory for human health issues, particularly those that have to do with climate and zoonotic disease - those that can be transferred from animals to humans. It's a measurable, visible impact. We're seeing new health threats in Alaska as a result of climate change."

Warming temperatures are likely to increase rainfall in the North, leading to increased run-off to ocean systems and melting of ice. These changes affect how contaminants are delivered to the food web, and thus to people. Habitat loss and increases in water temperature also allows both pathogens and disease vectors to move into new areas.

"The rest of the world is likely to see similar changes as we go forward in time. We're just seeing change more rapidly in Alaska," says Sandifer.

"What is happening in the Arctic will affect policy at the international and national level," adds O'Hara. "Native populations have said, this is our food, our way of life, not just our wildlife."

Getting the rest of the world to pay attention to the health of marine mammals may be the first step in mitigating potential human health impacts. "This is the age of discovery of new diseases and causes of marine mammal deaths," says Teri Rowles of NOAA. "We learn something new every single month, and we continue to gain insight into what is going on with the ecosystems in which marine mammals live. This information will help us tackle how to ensure the future health of the oceans - and ourselves." ###

Jim Berner, Alaska Native Tribal Health Consortium, Office: 907-729-3640

Gregory Bossart, Harbor Branch Oceanographic Institution, Cell: #722-473-2628

Pat Conrad, University of California at Davis, Cell: #530-304-4808

Frances Gulland, The Marine Mammal Center, Cell: #415-640-3769

Peggy Krahn, Northwest Fishery Science Center, NOAA, Cell: #206-697-5183

Todd O'Hara, University of Alaska Fairbanks, Office: #907-474-1838

Teri Rowles, Marine Mammal Health & Stranding Response Program, Cell: #301-675-8395

Paul Sandifer, Ocean and Human Health Initiative, NOAA, Cell: #843-297-6278

Contact: Jessica Brown jbrown@seaweb.org 202-497-8375 SeaWeb

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Presidential Podcast 02/18/06

Presidential Podcast 02/18/06

Subscribe to Our Odeo Podcast Channel and receive the Presidential Radio Address each week. Featuring real audio and full text transcript

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Freedom Calendar 02/18/06 - 02/25/06

February 18, 1946, Appointed by Republican President Calvin Coolidge, federal judge Paul McCormick ends segregation of Mexican-American children in California public schools.

February 19, 1976, President Gerald Ford formally rescinds President Franklin Roosevelt’s notorious Executive Order authorizing internment of over 120,000 Japanese-Americans during WWII.

February 20, 1895, Death of Republican activist Frederick Douglass – escaped slave, author, abolition leader, civil rights champion.

Presidents’ Day, February 21, 1863, Republican Governor John Andrew establishes the 54th Massachusetts, the famous regiment of African-American U.S. troops in which two of Frederick Douglass’ sons served.

February 22, 1856, First national meeting of the Republican Party, in Pittsburgh, to coordinate opposition to Democrats’ pro-slavery policies.

February 23, 1990, President George H. W. Bush nominates African-American Republican Arthur Fletcher as Chairman of the U.S. Civil Service Commission.

February 24, 1992, President George H. W. Bush appoints African-American Edward Perkins as U.S. Ambassador to United Nations.

February 25, 1870, A former slave, Mississippi Republican Hiram Revels, becomes first African-American U.S. Senator.

“Whenever I hear anyone arguing for slavery, I feel a strong impulse to see it tried on him personally.”

Abraham Lincoln, 16th President of the United States

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bush radio address 02/18/06 full audio, text transcript

bush radio address 02/18/06 full audio, text transcript PODCAST President's Radio Address

THE PRESIDENT: Good morning. This coming week, I will visit Wisconsin, Michigan, and Colorado, to discuss our strategy to ensure that America has affordable, reliable, and secure sources of energy. The best way to meet our growing energy needs is through advances in technology. So in my State of the Union Address, I announced the Advanced Energy Initiative. We will pursue promising technologies that will transform how we power our vehicles, businesses, and homes -- so we can reduce our Nation's dependence on foreign sources of energy.

This morning, I want to speak to you about one part of this initiative: our plans to expand the use of safe and clean nuclear power. Nuclear power generates large amounts of low-cost electricity without emitting air pollution or greenhouse gases. Yet nuclear power now produces only about 20 percent of America's electricity. It has the potential to play an even greater role. For example, over the past three decades, France has built 58 nuclear power plants and now gets more than 78 percent of its electricity from nuclear power. Yet here in America, we have not ordered a new nuclear power plant since the 1970s. So last summer I signed energy legislation that offered incentives to encourage the building of new nuclear plants in America. Our goal is to start the construction of new nuclear power plants by the end of this decade.

As America and other nations build more nuclear power plants, we must work together to address two challenges: We must dispose of nuclear waste safely, and we must keep nuclear technology and material out of the hands of terrorist networks and terrorist states.

To meet these challenges, my Administration has announced a bold new proposal called the Global Nuclear Energy Partnership. Under this partnership, America will work with nations that have advanced civilian nuclear energy programs, such as France, Japan, and Russia. Together, we will develop and deploy innovative, advanced reactors and new methods to recycle spent nuclear fuel. This will allow us to produce more energy, while dramatically reducing the amount of nuclear waste and eliminating the nuclear byproducts that unstable regimes or terrorists could use to make weapons.

As these technologies are developed, we will work with our partners to help developing countries meet their growing energy needs by providing them with small-scale reactors that will be secure and cost-effective. We will also ensure that these developing nations have a reliable nuclear fuel supply. In exchange, these countries would agree to use nuclear power only for civilian purposes and forego uranium enrichment and reprocessing activities that can be used to develop nuclear weapons. My new budget includes $250 million to launch this initiative. By working with other nations under the Global Nuclear Energy Partnership, we can provide the cheap, safe, and clean energy that growing economies need, while reducing the risk of nuclear proliferation.

As we expand our use of nuclear power, we're also pursuing a broader strategy to meet our energy needs. We're investing in technologies like solar and wind power and clean coal to power our homes and businesses. We're also investing in new car technologies like plug-in hybrid cars and in alternative fuels for automobiles like ethanol and biodiesel.

Transforming our energy supply will demand creativity and determination, and America has these qualities in abundance. Our Nation will continue to lead the world in innovation and technology. And by building a global partnership to spread the benefits of nuclear power, we'll create a safer, cleaner, and more prosperous world for future generations.

Thank you for listening.

END For Immediate Release, Office of the Press Secretary, February 18, 2006

more at President Bush and White House or Advanced Energy Initiative and Nuclear power, or greenhouse gases and hybrid cars, or alternative fuels, and ethanol,

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