August 16, 2009, 9:14 PM CT

Rare healing substances in the endangered Devil's claw plant

Deep in Africa's Kalahari Desert lies the "Devil's claw," a plant that may hold the key to effective therapys for arthritis, tendonitis and other illnesses that affect millions each year. Unfortunately, years of drought have pushed the Devil's claw toward extinction, so researchers are scrambling to devise new ways to produce the valuable medicinal chemicals of the Devil's claw and other rare plants.

One group of researchers reported a major advance toward that goal here today at the 238th National Meeting of the American Chemical Society (ACS). They described the first successful method of producing the active ingredients in Devil's claw ingredients that have made the Devil's claw a sensation in alternative medicine in Europe. Their technique may eventually lead to the development of "biofactories" that could produce huge quantities of rare plant extracts quickly and at little cost.

Milen I. Georgiev, Ph.D., who delivered the report, pointed out that for thousands of years, native populations in Southern Africa have used the Devil's claw as a remedy for a huge number of ailments, including fever, diarrhea and blood diseases. Today, there are dozens of medicinal and herbal products around the world that are based on chemicals derived from the Devil's claw.

In particular, studies suggest that two chemicals the so-called iridoid glycosides harpagoside and harpagide may have beneficial effects in the therapy of degenerative rheumatoid arthritis, osteoarthritis, tendonitis, and other conditions, Georgiev said......... Posted by: Erica      Read more         Source

August 16, 2009, 8:25 PM CT

Researchers sequence exomes of 12 people

In a pioneering effort that generated massive amounts of DNA sequence data from 12 people, a team supported by the National Institutes of Health (NIH) has demonstrated the feasibility and value of a new strategy for identifying relatively rare genetic variants that may cause or contribute to disease. The proof-of-concept findings were published online today in the journal Nature

The new strategy involves isolating and sequencing all exons which are the parts of the human genome that contain the information needed to produce proteins, the building blocks of the body. The complete set of exons referred to as the "exome" makes up only one percent of the human genome. By selecting only the exome to sequence, the important information about an individual can be obtained at a much lower cost than sequencing a person's entire genome. Evaluation of the results of exome sequencing is based on knowledge of the genetic code and allows for a more informative interpretation of genetic variants. Using the exome strategy, like other methods of direct DNA sequencing, researchers also can detect rare variants that typically provide a stronger indication of disease susceptibility.

This research, which was conducted by researchers from the University of Washington in Seattle, Wash., and Agilent Technologies in Santa Clara, Calif., was funded by the National Heart, Lung, and Blood Institute (NHLBI), the National Human Genome Research Institute (NHGRI), and the Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), which are all part of the NIH. It was carried out as part of The Exome Project, a program jointly managed by the NHLBI and the NHGRI that was established to develop, validate, and begin to apply a cost-effective, high-throughput approach for exome sequencing that can be deployed in large, well-phenotyped human populations......... Posted by: Janet      Read more         Source

August 13, 2009, 7:07 AM CT

Importance of niche differences in biodiversity

UC Santa Barbara have found good evidence that niche differences are critical to biodiversity. Their findings are published online in this week's issue of the journal Nature.

"Ecologists have long assumed that species differences in how they use the environment are key to explaining the large number of species we see all around us, but the importance of such niches have never been field tested," said first author Jonathan M. Levine, associate professor in UCSB's Department of Ecology, Evolution, and Marine Biology.

Levine and his co-author Janneke HilleRisLambers, a former postdoctoral fellow at UCSB, who is now an assistant professor at the University of Washington, did field testing of small plants. These plants were found in northern Santa Barbara County on rocky outcrops, where diversity is very high. They used a combination of mathematical techniques, as well as experimental approaches, to remove niche differences from these experimental communities.

"Our work is important because it resolves a century-old biodiversity puzzle," said Levine. "Why doesn't the single best competitor exclude all others in the community?".

Ecological theory has posed two possible answers to the coexistence conundrum. "The classic argument is that niche differences allow species to divide up the environment, much like different products cater to consumers of different tastes or incomes," he said. "The alternative is that competitors are so evenly matched that no single species can win as occurs when different airlines offer the same route for the same price"......... Posted by: Janet      Read more         Source

August 11, 2009, 11:21 PM CT

Round Goby invade Great Lakes

Canadian researchers uncover alarming invasion of round goby into Great Lakes tributaries: impact on endangered fishes likely to be serious.

A team of researchers from the University of Toronto, the Ontario Ministry of Natural Resources and the University of Guelph has identified a drastic invasion of round goby into a number of Great Lakes tributaries, including several areas of the Thames, Sydenham, Ausable and Grand Rivers. Many the affected areas are known as "species-at-risk" hot spots.

"This invasion poses a number of potential threats for native species of fish and mussels," says Mark Poos, a PhD Candidate in U of T's Department of Ecology and Evolutionary Biology. Poos is main author of the study published recently in the international journal Biological Invasions Up to 89 per cent of fish species and 17 per cent of mussel species are either known or suspected to be affected by the goby invasion. Of particular concern is the impact on species that have a conservation designation, including such endangered species as the small eastern sand darter fish and mussels such as the wavy rayed lampmussel.

The Great Lakes and its tributaries are Canada's most diverse aquatic ecosystems, but are also the most fragile, notes Poos. Several of these rivers hold species found nowhere else in Canada, including 11 endangered species and two threatened species. Furthermore, the round goby, an aggressive ground-feeder, is a threat to three globally rare species: the rayed bean, northern riffleshell and snuffbox mussels......... Posted by: Kelly      Read more         Source

August 6, 2009, 11:31 PM CT

A plant's arsenal of crystalline darts and sand

Pet owners have heard the warnings to keep certain poisonous houseplants away from their pets, such as Dieffenbachia (dumbcane), Philodendron, peace lily, and pothos. For houseplants like these and others, the problem may not just be a poison, but the presence of tiny crystals throughout the plant.

A discussion of plants may not bring to mind crystals; however, crystals are found in hundreds of plant families. Despite this, their purpose is not well-understood. Hypotheses include acting as a deterrent to herbivory, serving as a long-term storage depot for calcium, or providing extra support to various plant tissues.

To help elucidate the role of crystals in plants and determine whether this role may actually be to prevent animals from munching on the plant, Dr. Gary Cot studied the variety and locations of crystals found in the houseplant Dieffenbachia seguine. His findings have just been reported in the July 2009 issue of the American Journal of Botany

Three common types of crystals are found in plants: druses (spherical crystal aggregates), raphides (long pointed needles found in bundles), and prisms. Cot found all three of these in Dieffenbachia. He discovered that each type of tissue within the plant, as well as different portions of the same organ in some instances, had their own specific crystals. And, despite the variety of crystal structures found throughout the plant, all crystals were found to contain calcium oxalate, the same substance comprising kidney stones......... Posted by: Erica      Read more         Source

August 4, 2009, 8:29 AM CT

Sick fish may get sicker

Entire populations of North American fish already are being affected by several emerging diseases, a problem that threatens to increase in the future with climate change and other stresses on aquatic ecosystems, as per a noted U.S. Geological Survey researcher giving an invited talk on this subject today at the Wildlife Disease Association conference in Blaine, Wash.

"A generation ago, we couldn't have imaged the explosive growth in disease issues facing a number of of our wild fish populations," said Dr. Jim Winton, a fish disease specialist at the USGS Western Fisheries Research Center. "Most fish health research at that time was directed toward diseases of farmed fish".

In contrast, said Winton, recent studies in natural aquatic systems have revealed that, in addition to being a cause of natural death, infectious and parasitic fish diseases can produce significantly greater mortality in altered habitats leading to population fluctuations, extinction of endangered fish, reduced overall health and increased susceptibility to predation.

In addition, said Winton, populations of certain fish species have suffered catastrophic losses after non-native diseases were first introduced into a water body. Examples include whirling disease in the intermountain west and the recent introduction of viral hemorrhagic septicemia in the Great Lakes......... Posted by: Kelly      Read more         Source

August 4, 2009, 8:10 AM CT

Agricultural research key to food security

Boosting agricultural research in the developing world is the key to ensuring food security for the world's poorest, says Adel el-Beltagy, Chair of the Global Form on Agricultural Research (GFAR), writing in the latest issue of the TWAS Newsletter, published last week.

With nearly a billion people suffering from chronic hunger, global food security remains a major concern, despite being a key goal of the UN Millennium Development Goals (MDGs). Extreme weather events due to climate change and the recent trend to convert croplands to biofuels both threaten to put even more people who are at risk.

The solution, says el-Beltagy a member of TWAS, the Academy of Sciences for the Developing World must involve a renewed concentration on agricultural research in the South.

Writing in the spring issue of the TWAS Newsletter, el-Beltagy outlines the steps that will be needed to ensure that developing countries can take advantage of cutting-edge agricultural technologies, such as genomics and nanotechnology, that have the potential to increase crop yields without unduly stressing the environment.

Building such capacity will depend upon overcoming.

two obstacles: The North-South gap, which delays the transfer of technologies to the developing world, and the gap between developing world research communities and farmers working in the field......... Posted by: Erica      Read more         Source

July 29, 2009, 11:17 PM CT

Researchers link jellyfish, other small sea creatures to large-scale ocean mixing

The ocean's smallest swimming animals, such as jellyfish, can have a huge impact on large-scale ocean mixing, scientists have discovered.

"The perspective we commonly take is how the ocean--by its currents, temperature, and chemistry--is affecting animals," says John Dabiri, a Caltech bioengineer who, along with Caltech graduate student Kakani Katija, discovered the new mechanism. "But there have been increasing suggestions that the inverse is also important, how the animals themselves, via swimming, might impact the ocean environment".

Dabiri's and Katija's findings show this inverse to be true, and are reported in the July 30 issue of the journal Nature

"Results from this study will change some of our long-held conceptions about mixing processes in the oceans," says David Garrison, director of NSF's biological oceanography program, which funded the research.

Researchers have increasingly been thinking about how and whether the animals in the ocean might play a role in larger-scale ocean mixing, says Dabiri, the process by which various layers of water interact with one another to distribute heat, nutrients and gasses throughout the oceans.

He says that oceanographers had previously dismissed the idea that animals might have a significant effect on ocean mixing, believing that the viscosity of water would cancel out any turbulence created, particularly by small planktonic, or drifting, animals......... Posted by: Kelly      Read more         Source

July 28, 2009, 11:46 PM CT

Mapping the crocodile genome

The first ever genetic linkage map for a non-avian member of the Class Reptilia has been developed. Scientists writing in the open access journal BMC Genomics have constructed a first-generation genetic linkage map for the saltwater crocodile Crocodylus porosus.

Dr Lee Miles, from the University of Sydney, worked with a team of Australian and international scientists to study a population of saltwater crocodiles from the Darwin Crocodile Farm in the Northern Territory. He said, "This map will be a valuable resource for crocodilian researchers, facilitating the systematic genome scans necessary for identifying genes affecting complex traits of economic importance in the crocodile industry".

The researchers' map also provides a significant step towards the elucidation of the crocodilian genome, forming a scaffold for genome sequence assembly, and will be of intrinsic value to comparative mapping efforts aimed at understanding the molecular evolution of reptilian, as well as other amniote genomes. From an economic perspective, this new information should be able to assist in the breeding of farmed crocodiles with favourable growth rate, survival and skin quality by facilitating the systematic searches necessary to identify the genes that affect these traits......... Posted by: Kelly      Read more         Source

July 28, 2009, 11:42 PM CT

Study sheds light on squirrel psychology

The research team tested the squirrels' ability to learn to choose between two pots of food after watching another squirrel remove a nut from one of the pots. One group was rewarded for choosing the same pot as the prior squirrel, the second group was rewarded for targeting the other pot. Those that were rewarded for choosing food from the other pot learned more quickly than those that were rewarded for choosing the same pot. This suggests that grey squirrels learn more quickly to recognise the absence of food.

The study was repeated, but instead of observing another squirrel, the animals were trained with the use of a card. In this test, the squirrels showed no significant difference in their ability to learn to choose the same or opposite pot.

The study suggests that squirrels are primed to recognise other squirrels as potential food thieves. It also shows that they learn more quickly from real life observations.

Corresponding author Dr Lisa Leaver of the University of Exeter, said: "Our study is significant because it is the first to show that grey squirrels learn from observing others. It adds to growing evidence that all kinds of animals, from humans and other primates to a number of species of birds, learn from observation and that they have evolved to learn quickly about those things that are most important to their lives in the case of grey squirrels, gathering and storing nuts"......... Posted by: Kelly      Read more         Source