AmeriScan: October 25, 2001


ST. LOUIS, Missouri, October 25, 2001 (ENS) - Scientists at Washington University School of Medicine in St. Louis have mapped and sequenced the genome for a bacterium that is a leading cause of food poisoning worldwide: Salmonella typhimurium.

The sequence has yielded new potential targets for future drug and vaccine development and gives possible insights into how the bacterium causes disease. The work appears in the today's issue of the journal "Nature."

Typhimurium infects humans, cattle, chickens, and other warm blooded animals. The rod shaped bacterium is important in bacterial genetics research, and disabled strains are used in live vaccines and to deliver anti-cancer drugs to tumor cells.

It also causes a typhoid fever like illness in mice that is used as a model for studies related to human typhoid fever. Typhimurium is thought to be responsible for an estimated 1.4 million cases of food poisoning in the United States each year, and about 1,000 deaths.

The intestinal illness often resolves on its own, but sometimes the bacterium enters the bloodstream, causing an infection that may be fatal if not treated with antibiotics. That treatment is becoming more difficult.

"Antibiotic resistance is a growing problem in Typhimurium," said principal investigator Richard Wilson, Ph.D., associate professor of genetics and codirector of the Genome Sequencing Center at the university School of Medicine. "Ideally, we hope this work will identify possible new drug targets and reduce the threat of ever more resistant strains of the bacterium."

In addition to researchers at Washington University, the Typhimurium team included investigators at the Sidney Kimmel Cancer Center in San Diego; the University of Calgary in Alberta, Canada; and Pennsylvania State University.

The investigators identified 4,595 suspected genes in the Typhimurium genome, many of which had not been known. They include 156 probable membrane proteins that are potential drug or vaccine targets.

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SEATTLE, Washington, October 25, 2001 (ENS) - Climate change, not early hunters, led to the extinction on many large North American mammals, argues a University of Washington (UW) archaeologist in two new papers.

Scientists have been picking over the bones of extinct mammoths, mastodons and other megafauna for more than three decades, but can not agree on what caused the extinction of many of the continent's large mammals. Many biologists have blamed prehistoric hunters for wiping out these animals.

The overkill hypothesis was proposed by University of Arizona ecologist Paul Martin in 1967. It claims large mammal extinctions occurred 11,000 years ago, after the entry of the Clovis people, the first to enter North America.

Clovis people were hunters who preyed on a diverse set of now extinct large mammals. Records from islands show that human colonists cause extinction - therefore, Graham hypothesized, Clovis people may have caused extinctions.

"While the initial presentation of the overkill hypothesis was good and productive science, it has now become something more akin to a faith based policy statement than to a scientific statement about the past," said Donald Grayson, a UW anthropology professor

"Martin's theory is glitzy, easy to understand and fits with our image of ourselves as all-powerful," said Grayson "It also fits well with the modern Green movement and the Judeo-Christian view of our place in the world. But there is no reason to believe that the early peoples of North America did what Martin's argument says they did."

Writing in the current issue of the "Journal of World Prehistory" and in a paper to be published in a forthcoming issue of the "Bulletin of the Florida Museum of Natural History," Grayson said there are dangerous environmental implications of using overkill hypothesis as the basis for introducing exotic mammals into arid western North America.

He looks askance at the idea of introducing modern elephants, camels and other large herbivores into the southwest United States.

"Overkill proponents have argued that these animals would still be around if people hadn't killed them and that ecological niches still exist for them. Those niches do not exist," argued Grayson. "Otherwise the herbivores would still be there."

If early humans did not kill North America's megafauna, then what did? Grayson points to climate shifts, during the late Pleistocene epoch which ended about 10,000 years ago, and subsequent changes in weather and plants as the culprits in the demise of North America's megafauna.

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PORTLAND, Oregon, October 25, 2001 (ENS) - The U.S. Fish and Wildlife Service (USFWS) has proposed to designate critical habitat for the Kneeland Prairie penny-cress, an endangered native California plant, on about 74 acres of serpentine outcrops in the grasslands of Kneeland Prairie, Humboldt County, California.

Under the Endangered Species Act, a critical habitat designation identifies the a geographic area that is essential for the conservation of a threatened or endangered species and may require special management considerations or protection. When mapping the proposed critical habitat, USFWS biologists attempted to exclude developed areas such as roads and buildings because these areas do not support habitat for the Kneeland Praire penny-cress.

About 84 percent of the total acreage proposed for critical habitat for the Kneeland Prairie penny-cress is private land. State lands make up five percent of the proposal, while county lands account for 11 percent.


Kneeland Prairie penny-cress (Photo courtesy UFSWS)
The Kneeland Prairie penny-cress was listed as endangered under the federal Endangered Species Act in February 2000. The species occurs in small populations with limited distribution, making it vulnerable to extinction from manmade and natural causes.

About 5,300 plants are distributed in five colonies in one general location. The colonies are bisected by the Kneeland Airport and a county road.

The population is threatened with habitat loss due to construction, maintenance and development activities, hydrologic changes and other ground disturbing activities.

On June 17, 2000, the Center for Biological Diversity filed a complaint in the U.S. District Court for the Northern District of California against the USFWS and the Secretary of the Interior for failure to designate critical habitat for the Kneeland Prairie penny-cress.

On May 19, 2000, the court issued a joint stipulation and proposed order setting the timetable for critical habitat designation. The USFWS agreed to propose critical habitat for the species by September 30, 2001, and complete the final rule by May 1, 2002.

The USFWS is asking the public to submit any additional information and data about the species, including economic or other impacts of these designations. Comments are invited until December 24, 2001, and may be emailed to:

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ROCHESTER, New York, October 25, 2001 (ENS) - Testing conducted at local playgrounds in Rochester, New York reveals unsafe levels of arsenic, says the group Rochesterians Against the Misuse of Pesticides (RAMP).

RAMP conducted soil testing at both public park and public school sites that have playground equipment built of pressure treated lumber. Results reveal high levels of arsenic.

"Arsenic can cause neurological damage, birth defects, reproductive toxicity, impair the immune system and is known to cause cancer," said Pamela Hadad Hurst, executive director of the New York Coalition for Alternatives to Pesticides (NYCAP). "It is frightening to learn that our children are rolling around in this stuff at levels that are 24 times higher than the States threshold for soil contamination."

Children often put their hands and other objects into their mouths, adding to their risk from contaminated soil and treated lumber. Wooden playground equipment is often treated with chromated copper arsenicals (CCA), a wood preservative that contains arsenic.

"Children face an unreasonable risk of cancer every time they play on or near CCA treated wood playground equipment," said Jay Feldman, executive director of Beyond Pesticides.

Field studies and laboratory tests have shown that hazardous amounts of arsenic in CCA can leach out of pressure treated lumber. The arsenic then may be ingested or absorbed by humans or animals and may contaminate water sources and soil below the wood.

CCA has been banned in several countries. Alternatives to CCA include ACQ, a wood preservative that does not include arsenic.

RAMP has asked the Center for Environmental Health of the New York State Health Department to test all pressure treated wood playgrounds for arsenic on public property in New York State before the ground freezes. RAMP is also calling for the closing of all playgrounds in the Monroe County area which have tested positive for arsenic.

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GAINESVILLE, Florida, October 25, 2001 (ENS) - An indoor air cleaning system developed to zap dust mites and mold spores also destroys airborne anthrax and other pathogenic microbes, says the University of Florida (UF) engineering professor who pioneered the technology.

The system has been tested against a close cousin of the anthrax bacteria and could be installed in office and home heating and air conditioning systems at low cost, said Yogi Goswami, a UF professor of mechanical engineering and director of UF's Solar Energy and Energy Conversion Laboratory. "There are other technologies for air cleaning, but for air disinfection, there is no more effective system."

The air cleaning system relies on the interaction between light and titanium dioxide, a common chemical. When light is absorbed into the titanium dioxide, it acts as a catalyst to produce an oxidizing agent.

The agent, called a hydroxyl radical, "is like a bullet for the bacteria," Goswami said, destroying dust mites, mold spores and pathogens by disrupting or disintegrating their DNA.

Goswami came up with the system in the mid 1990s as a cure for sick building syndrome, when poor ventilation and a build up of mold or mildew cause illnesses for people who work inside. Initial research proved that the system kills the mold spore aspergillus niger, considered to be one of nature's hardiest spores, he said.

More recent research has shown that the system also destroys bacillus subtilis, a spore that causes food spoilage and is a cousin of the anthrax spore, bacillus anthracis.

"In the laboratory, we normally test with nonpathogenic bacteria that are closely related to pathogenic bacteria, so there's no risk to people," Goswami said. "As we expected, our tests showed the system was effective against bacillus subtilis."

The technology is an improvement over traditional filter based systems in part because there is no opportunity for bacteria to collect and multiply on the filters that clear it from the air, he said.

"Filters can actually increase the danger because they concentrate the bacteria," said Goswami.

The system is also an improvement over systems that use ultraviolet light, which do not always kill all the bacteria, he said.

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CINCINNATI, Ohio, October 25, 2001 (ENS) - Four new children's environmental health research centers that will focus on childhood autism and such behavioral problems as attention deficit disorder were designated today.

U.S. Environmental Protection Agency (EPA) Administrator Christie Whitman and National Institute of Environmental Health Sciences' director Dr. Kenneth Olden made the announcement during a visit to Children's Hospital in Cincinnati.

"These new centers - and the eight already in existence across the country - will continue to perform and apply research that can help shed light on the links between the environment and the health of our children," said Whitman. "They can help us take children's health protection to a new level, and I am proud to be working with NIEHS and everyone at UC-Davis, University of Illinois, Robert Wood Johnson, and this wonderful Children's Hospital to make it happen."

The new centers will receive $5 million, or about $1 million per year for five years. The EPA and NIEHS, part of the federal National Institutes of Health and the Department of Health and Human Services, already fund eight children's environmental health research centers.

Children's Hospital Medical Center of Cincinnati will work with community participants to assess the impact of reducing pollutants in the home and neighborhood on children's hearing, behavior and test scores. A center at the University of Illinois at Champaign/Urbana will assess the impact of exposure to mercury and PCBs among two groups of Asian-Americans in Wisconsin, whose diets are heavy in fish from the Great Lakes.

At the University of California at Davis and the Robert Wood Johnson Medical School of the University of Medicine and Dentistry of New Jersey, researchers will study environmental factors that may be related to autism.

"These centers will help us understand whether environmental factors play a role in the progress of autism and other childhood disorders and illnesses," Health and Human Services Secretary Tommy Thompson said. "Ultimately the research conducted at these centers will allow us to better target our health and prevention efforts in order to do the most to improve the lives of America's children."

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BLACKSBURG, Virginia, October 25, 2001 (ENS) - Virginia Tech introduced its new Horseshoe Crab Research Center (HCRC) today. With more than 200 adult crabs, it is the largest captive system in the nation.

The research center has been established to provide information necessary to improve the management of the species.

"Over the past several years, management of the horseshoe crab population has become increasingly controversial," said center director Jim Berkson. "Fishermen catch horseshoe crabs for use as bait in the lucrative eel and conch fishery."

Biomedical companies catch and bleed horseshoe crabs to produce a chemical (LAL) used to detect the presence of bacteria in injectable drugs and implantable devices. Environmentalists are concerned because migratory shorebirds depend on horseshoe crab eggs to fuel their migration to their arctic breeding grounds each year.

"The battle over this ecologically, economically, and medically essential species has become one of the most heated environmental issues on the east coast in recent years," said Berkson.

Participating in the dedication were officials from three federal agencies involved in horseshoe crab research and management, agencies responsible for horseshoe crab management in several states, environmental groups, including the Audubon Society, and biomedical companies including the largest producer of LAL, BioWhittaker Inc.

The HCRC was founded on the belief that developing effective management strategies requires an understanding of all three dimensions of the horseshoe crab issue: fisheries, shorebirds and biomedical companies.

The HCRC combines faculty members, students, facilities, and expertise from Virginia Tech's Department of Fisheries and Wildlife Sciences in the College of Natural Resources, Virginia-Maryland Regional College of Veterinary Medicine, Conservation Management Institute, and the Virginia Bioinformatics Institute.

These HCRC's partners have formed the sole research center in the country with the knowledge, experience, and facilities needed to work on all three dimensions of the horseshoe crab issue.

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RALEIGH, North Carolina, October 25, 2001 (ENS) - Blue Ridge Paper Products Inc. of Canton, North Carolina will have to reduce the amount of color discharged from its pulp and paper mill into the Pigeon River by 18 to 33 percent over the next five years.

A committee of the North Carolina Environmental Management Commission stipulated the reductions in a color variance it approved for the company. Color is a byproduct of a bleaching process to convert wood chips into paper products.

Wastewater effluent containing color can change the appearance of a water body, with some streams appearing darker in hue.

"Major strides have been made over the past decade to reduce color in the river and to improve water quality," said Mike Myers, an engineer with the Division of Water Quality's (DWQ) point source permitting branch. "These additional color reductions will continue the clean up of the Pigeon River while still keeping the company viable."

The DWQ has been working with the state of Tennessee and the U.S. Environmental Protection Agency in developing the color variance.

Built in 1908, the mill is located about 40 miles upstream from the Tennessee border on a stretch of river that has seen water quality improvements in recent years, leading to an increase in recreational usage including whitewater rafting.

Blue Ridge Paper has already reduced the amount of color discharged into the river from about 400,000 pounds per day in the mid 1980s to less than 48,000 pounds per day today. The variance will further reduce that level to between 32,000 to 39,000 pounds per day on average.

The plant is permitted to discharge 29.9 million gallons of treated wastewater each day into the Pigeon River in the French Broad River Basin. Champion International Corp. of Stamford, Connecticut owned and operated the plant until 1999, when employees purchased and renamed it.

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SEATTLE, Washington, October 25, 2001 (ENS) - The Puget Sound Environmental Learning Center today launched a multi-million-dollar fundraising campaign to complete the construction of the region's newest outdoor education facilities.

John Warner, senior vice president and chief administrative officer of The Boeing Company, kicked off today's campaign launch at Seattle's John Muir Elementary School by announcing a $1 million corporate gift to the Bainbridge Island based organization.

The gift from Boeing brings the total raised by the nonprofit group to $38 million. The capital campaign's goal is to raise the remaining $14 million - for a total of $52 million - over the next 14 months.

"The more we discovered about the philosophy and program initiatives of the Puget Sound Environmental Learning Center, the more we were convinced that this organization could make a long term, positive impact on how children learn," Warner said. "Combining science, technology and the arts, in an outdoor classroom filled with trees, bogs, ponds, bugs and animals allows students to experience, first hand, a curriculum that can teach them a sense of long-term stewardship for their community and the environment."

Opening in the fall of 2002, the Puget Sound Environmental Learning Center will, each year, serve more than 7,000 Puget Sound area students and teachers. The program is focused on hands on learning for school age children, teachers and families.

The center's location on 255 acres of forests and wetlands will allow the organization to combine its spectacular natural surroundings with art and technology to offer an interactive, ecologically based science and humanities program that promotes environmental stewardship.

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NAPA, California, October 25, 2001 (ENS) - Acacia Vineyard employees spent today planting black walnut and coastal oak trees and a row of wild rose bushes in the Napa-Sonoma Marshes Wildlife Area (NSMWA).

The day of planting is just one way that Acacia is partnering with the California Department of Fish and Game (CDFG) to restore habitat for waterfowl and other wildlife in the NSMWA, which defines the southern edge of Napa and Sonoma counties.

Encompassing more than 13,000 acres, NSMWA is a little known wildlife area in the San Francisco Bay Area's backyard. This mix of wetlands, sloughs and rivers was altered by hay farms, which drained portions of the marsh, and by the development of salt evaporating ponds.

Restoring these wetlands is critical to wildlife lovers since more than 82 percent of the Bay Area's original tidal wetlands system has already disappeared, the CDFG estimates.

The marsh provides important habitat for a variety of fish, wildlife and plant species, including 25 species of waterfowl and several threatened or endangered bird, plant, mammal and fish species. The marsh abuts the Carneros District, a grape growing region that is the home of Acacia Vineyard, one of several wineries that take advantage of the shallow, dense clay soils and the cool bay winds of the Carneros to grow Chardonnay and Pinot Noir grapes.

Acacia employees planted oaks to provide cover and food for the expanding wildlife community around the marsh. The wild roses will form a living fence that provides cover, feed, building material for nests, and a natural demarcation at the edge of the area.

To help these young plants flourish, Acacia has also donated and installed a drip irrigation line.

"We have years of experience with drip systems, and it seemed like a natural step to use this expertise to help restore the natural plant systems in the marsh," said Acacia vineyard manager Bill Murray. "We're proud to use our knowledge to help our neighbor."

Earlier this year, Acacia employees constructed a wildlife viewing blind at the same location, a roofed hut overlooking a fresh water pond where shorebirds and geese make their home. From the blind, a quiet nature lover can observe wildlife as they visit the restored pond.