Daily Science Journal (Feb. 13, 2008) — One drink of either red wine or alcohol slightly benefits the heart and blood vessels, but the positive effects on specific biological markers disappear with two drinks, say researchers at the Peter Munk Cardiac Centre of the Toronto General Hospital.

Researchers conducted a real-time study of thirteen volunteers to determine whether a red wine with a verified high polyphenol content differs from alcohol in its effects on specific markers associated with a greater risk of high blood pressure, coronary artery disease and heart failure.

A large number of population studies have shown a protective effect of light or moderate alcohol drinking against the risk of death and the development of heart disease. Many studies have also reported specific benefits of red wine.

Population surveys found lower rates of heart disease, despite high-fat diets, in some European countries where red wine was consumed regularly. Widely known at the French paradox, this has created a huge interest in exploring if and how red wine has a protective effect against heart disease.

However, the findings of this study* showed virtually identical effects of red wine and alcohol on the specific markers tested. After one drink of either red wine or alcohol, blood vessels were more “relaxed” or dilated, which reduced the amount of work the heart had to do. But, after two drinks, the heart rate, amount of blood pumped out of the heart, and action of the sympathetic nervous system all increased. At the same time, the ability of the blood vessels to expand in response to an increase in blood flow diminished. This counteracted the beneficial effect of one drink of red wine or alcohol.

“We had anticipated that many of the effects of one ethanol drink would be enhanced by red wine. What was most surprising was how similar the effects were of red wine and ethanol. Any benefits that we found were not specific to red wine,” said Dr. John Floras, Director of Cardiology Research at the Peter Munk Cardiac Centre, and at Mount Sinai Hospital, in whose laboratory the study was performed. However, Dr. Floras cautioned this study measured the effects of these drinks on one occasion only. The effects of daily wine or alcohol intake may be quite different.

The laboratory of Dr. Floras, who holds the Canada Research Chair in Integrative Cardiovascular Biology and is a Professor of Medicine at the University of Toronto, and a Career Investigator of the Heart and Stroke Foundation, is one of the few in the world equipped to measure simultaneously a broad spectrum of factors such as blood pressure, heart rate, sympathetic nerve firing and arterial diameter.

Healthy, non-smoking adults who were not heavy drinkers or total alcohol abstainers were studied. Participants attended three separate morning sessions during which “standard” drinks of red wine, ethanol or water were administered at random, single-blind, two weeks apart. A 4-oz glass of wine (120 ml), and a 1.5-oz (44 ml) shot of spirits is considered to be one standard drink. All blood alcohol levels alcoholic were below .08, the legal limit for drivers.

The Quality Assurance Laboratory of the Liquor Control Board of Ontario selected a moderately priced pinot noir with a verified high t-resveratrol content, a polyphenol compound found in plants, including red grapes, which exhibits antioxidant properties. Alcohol or substances in alcohol such as resveratrol may improve blood vessel function and also prevent platelets in the blood from sticking together, which may reduce clot formation and the risk of heart attack or stroke.

Select study findings:

One drink of either red wine or alcohol:

* Has no effect on heart rate, blood pressure or sympathetic nerve activity, which activates the “fight or flight” reaction and generally modulates heart rate and sets the diameter of blood vessels in order to redistribute blood;
* Dilates the brachial artery.

Two drinks of either alcohol or red wine:

* Increase sympathetic nerve activity, heart rate, and the amount of blood the heart pumps out, and also blunt the ability of the brachial artery to expand further in response to blood flow.
* Increases in heart rate and sympathetic nerve activity are recognized markers for hypertension (high blood pressure), heart failure and sudden death.

“Our findings point to a slight beneficial effect of one drink – be it alcohol or red wine – on the heart and blood vessels, whereas two or more drinks would seem to turn on systems that stress the circulation. If these actions are repeated frequently because of high alcohol consumption these effects may expose individuals to a higher risk of heart attacks, stroke or chronic high blood pressure,” noted Dr. Floras, adding that the American Heart Association (AHA) does not recommend that anyone start drinking alcohol to prevent heart disease. Reducing risk can be done using other methods such as exercise and following a healthy diet.

The study entitled “Dose-related effects of red wine and alcohol on hemodynamics, sympathetic nerve activity, and arterial diameter”, was published in the February edition of the American Journal of Physiology, Heart and Circulatory Physiology. This study was supported by the Heart and Stroke Foundation of Ontario, the Canadian Institutes of Health Research, and the Canada Research Chairs Program.

Adapted from materials provided by University Health Network, via Newswise.

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Daily Science Journal (Feb. 13, 2008) — A unique collaboration between scientists, public health workers and police has led to the arrest by the Chinese authorities of alleged traders of fake anti-malarial drugs in southern China and the seizure of a large quantity of drugs. The work, involving teams from across the globe, has highlighted both the growing threat posed by fake pharmaceuticals and the complexities of tracking down those responsible for the trade.

Counterfeit artesunate anti-malarial tablet with fake 'X-52' stamp as seen under UV light. (Credit: Newton PN, Fernandez FM, Plancon A, Mildenhall DC, Green MD,et al.)

Dubbed Operation Jupiter, the investigation was coordinated by the International Criminal Police Organisation (INTERPOL), the World Health Organization's Western Pacific Regional Office, and the Wellcome Trust-University of Oxford SE Asian Tropical Medicine Research Programme, in close cooperation with Chinese authorities. Scientists from 5 other laboratories analysed the composition of the fake drugs and their packaging.

Fake anti-malarial drugs are an increasingly serious problem, particularly in South-East Asia and Africa. In countries with a large burden of malaria, such as Myanmar (Burma), the Lao PDR, Cambodia and Viet Nam, as many as half of all artesunate tablets -- one of the most effective anti-malarial drugs -- is counterfeit.

Most of the fakes examined as part of Operation Jupiter contained no artesunate, and some contained a wide range of potentially toxic wrong active ingredients. Also of grave concern was the fact that counterfeiters sometimes included dangerously small amounts of artesunate in the tablets. This may be done to foil screening tests of drug quality, but these doses are too low to be efficacious, yet high enough to contribute to malaria parasites becoming resistant to this class of drugs.

"Artesunate, as part of artemisinin-based combination therapy, is vital for malaria treatment and is one of the most effective weapons we have against this terrible scourge," says Dr Paul Newton of the Wellcome Trust-University of Oxford SE Asian Tropical Medicine Research Programme. "Those who make fake anti-malarials have killed with impunity, directly through the criminal production of a medicine lacking active ingredients and by encouraging drug resistance to spread. If malaria becomes resistant to artesunate, the effect on public health in the tropics will be catastrophic."

In addition to analysing the chemistry of the samples, researchers used a technique known as forensic palynology to study pollen contamination within the fake tablets with the aim of tracking down the likely location of manufacture. The pollen evidence suggested that at least some of the counterfeit artesunate came from southern China, and this was supported by examination of the mineral calcite, found in some of the samples.

Armed with these findings by INTERPOL, Chinese authorities arrested a suspect in China's Yunnan Province in 2006. He is alleged to have traded 240,000 blisterpacks of counterfeit artesunate, enough to "treat" almost a quarter of a million adults with a medicine with no activity against a potentially fatal disease. Whilst the Chinese authorities were able to seize 24,000 of these packs, the remainder are alleged to have been sold at crossings on the border of Yunnan and Myanmar (Burma), accounting for almost a half of all blisterpacks of artesunate sold to the region.

The work of the Jupiter group highlights the need for more to be done internationally to support countries with a high prevalence of counterfeit anti-malarials in their attempts to combat this severe but under-recognised public health problem.

"Criminal investigations and legal action are important in disrupting and inhibiting the trade in fake medicines, but to be effective these will require financial support and resources," says Dr Newton. "Forensic tools may make it easier to identify the fake drugs and allow over-stretched police forces to focus on objective leads, greatly increasing the risks to counterfeiters of being caught. However, there are very few laboratories with the resources to perform detailed forensic chemistry or pollen analysis of fakes, particularly in the countries where they are most needed."

Journal citation: Newton PN, Fernandez FM, Plancon A, Mildenhall DC, Green MD,et al. (2008) A collaborative epidemiological investigation into the criminal fake artesunate trade in South East Asia. PLoS Med 5(2): e32.

Adapted from materials provided by Wellcome Trust.

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Daily Science Journal (Feb. 13, 2008) — The 24th shuttle flight to the International Space Station, STS-122, delivers Columbus, the European Space Agency's new laboratory. Columbus will be installed on Harmony Node 2.

European astronaut and station flight engineer Leopold Eyharts photographs the inside of the new Columbus laboratory. In the foreground is European astronaut and mission specialist Hans Schlegel. (Credit: NASA TV)

European astronaut and station flight engineer Leopold Eyharts got a look inside the new Columbus laboratory around 9 a.m. EST February 12. Official ingress is scheduled to occur at 2:55 p.m after preliminary outfitting of the new lab.

Supplies and equipment will be transferred into the European Space Agency’s Columbus laboratory. Three of the laboratory module’s five payload racks also are scheduled for relocation Feb. 12. Expedition 16 crew members Leopold Eyharts and Peggy Whitson will be the first to enter Columbus.

Later in the day, STS-122 Mission Specialists Rex Walheim and Hans Schlegel will camp out in the station’s Quest Airlock in preparation for the Feb. 13 spacewalk, scheduled for 9:35 a.m. EST.

On Feb 11, astronauts used the station’s robotic arm to connect Columbus to the orbital outpost and Walheim and Mission Specialist Stanley Love conducted the first of three scheduled STS-122 spacewalks. Among other tasks, the spacewalkers prepared the new module for its installation.

Adapted from materials provided by National Aeronautics And Space Adminstration.

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Daily Science Journal (Feb. 13, 2008) — A new type of membrane, developed by scientists of the University of Twente in The Netherlands, can stand high temperatures for a long period of time. This ‘molecular sieve’ is capable of removing water out of e.g. solvents and biofuels. It is a very energy efficient alternative to existing techniques like distillation.

The cylinder is the carrier of a hybrid membrane: a layer of about 100 nanometer thickness. The insert shows a close-up of the layer showing the organic links and pores. From the left of the tube, only water molecules leave the sieve. (Credit: Image courtesy of University of Twente)

Even after testing during 18 months, the new membranes prove to be highly effective, while having continuously been exposed to a temperature of 150 ºC. Existing ceramic and polymer membranes will last considerably shorter periods of time, when exposed to the combination of water and high temperatures. The scientists managed to do this using a new ‘hybrid’ type of material combining the best of both worlds of polymer and ceramic membranes. The result is a membrane with pores sufficiently small to let only the smallest molecules pass through.

Ceramic membranes, made of silica, degrade because they react with water and steam. In the new membrane, part of the ceramic links is therefore replaced by organic links. By doing this, water doesn’t have the chance to ‘attack’ the membranes. Manufacturing the new hybrid membranes is simpler than that of ceramic membranes, because the material is flexible and will not show cracks. What they have in common with ceramic membranes is the rapid flow: an advantage of this is that the membrane surface can be kept small.

The hybrid membranes are suitable for ‘drying’ solvents and biofuels, an application for which there is a large potential market worldwide. The main advantage of membrane technology is that it consumes far less energy than common distillation techniques.

The scientists also foresee opportunities in separating hydrogen gas from gas mixtures. This implies a broad range of applications in sustainable energy. Apart from that, the hybrid membranes are suitable for desalinating water. Using a hybrid membrane that is much smaller than the current polymer membranes, the same result can be achieved.

The results have been achieved in a close cooperation of scientists from the Inorganic Materials Science Group of the MESA+ Institute for Nanotechnology (UT), the Energy Efficiency in Industry department of ECN and the University of Amsterdam. The invention has been patented worldwide.

The article ‘Hybrid ceramic nanosieves: stabilizing nanopores with organic links’ by Hessel Castricum, Ashima Sah, Robert Kreiter, Dave Blank, Jaap Vente and André ten Elshof has been published in Chemical Communications (ChemComm) of the Royal Society of Chemistry in de UK.

Adapted from materials provided by University of Twente.

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Daily Science Journal (Feb. 13, 2008) — If humans had see-through skin like a jellyfish, spotting disease like cancer would be a snap: Just look, and see a tumor form or grow.

Diagram of chicken breast tissue (approximately 250 microns thick) with photo-refractive crystal to counteract the scattering of light and remove the distortion it creates in images. The lower diagram would show the clearest image. (Credit: Caltech Biophotonics Laboratory)

But humans, of course, are not remotely diaphanous. "The reason a person is not transparent is that their tissues are highly scattering," sending light waves careening through the tissue instead of straight through, as they would through the tissue of that jellyfish, explains Changhuei Yang of the California Institute of Technology.

This scattering, in addition to rendering all of us opaque, makes the detection of disease a much trickier issue, requiring a host of diagnostic tests and procedures. But not, perhaps, for much longer, thanks to a new optical trick developed by Yang, an assistant professor of electrical engineering and bioengineering, and his colleagues, that counteracts the scattering of light and removes the distortion it creates in images.

It is well known that light scattering in a material is not exactly the random and unpredictable process one might imagine. In fact, scattering is deterministic, which means that the path that a beam of light takes as it traverses a particular slice of tissue and bounces and rebounds off of individual cells, is entirely predictable; if you again bounce light through that same swath of cells, it will scatter in exactly the same way.

The process is even reversible; if the individual photons of light that scattered through the tissue could be collected and sent back through the tissue, they'd bounce back along the same path and converge at the original spot from which they were sent. "The process is similar to the scattering of billiard balls on a pool table. If you can precisely reverse the paths and velocities of the billiard balls, you can cause the billiard balls to reassemble themselves into a rack," Yang explains.

Yang, along with his colleagues at Caltech, École Polytechnique Fédérale de Lausanne in Switzerland, and MIT, exploited this phenomenon to offset the murky nature of our tissues.

Their technique, called turbidity suppression by optical phase conjugation (TSOPC), is surprisingly simple. The scientists used a holographic crystal to record the scattered light pattern emerging from a 0.46-mm-thick piece of chicken breast. They then holographically played the pattern back through the tissue section to recover the original light beam. "This is similar to grabbing hold of the direction of time flow and turning it around; the time-reversed photons must retrace their trajectories through the tissue," Yang says. "The task is formidable though, as this is comparable to starting with a rack of 10 to the 18th power billiard balls (or photons), scattering them around the table, and attempting to reassemble them into a rack."

"Until we did this study, it wasn't clear that the effect will be observable with biological tissues. We were pleasantly surprised that the effect was readily observable and remarkably robust," Yang says. "This study opens up numerous possibilities in the use of optical time reversal in biomedicine."

One possible use of the technique is in photodynamic therapy, in which a highly focused beam of light is aimed at cancerous cells that have absorbed cell-killing light-sensitive compounds. When the light hits the cells, the compounds are activated and destroy the cells. Photodynamic therapy is most effective in treating cancers on the skin surface. Yang's technique, however, offers a way to concentrate light onto cancer-killing compounds located more deeply within tissue.

Yang's idea is to inject strongly light-scattering particles that are coated with light-activated cancer-killing drugs into diseased tissue. Shine a beam of light into the tissue, and it would be reflected off the scattering compounds as it bounces through the tissue. Some of the scattered light would return to the source, where it could be recorded as a hologram.

This hologram would contain information about the path that the scattered light took through the tissue, and, in effect, describe the optimal path BACK toward the light-scattering molecule--and the cancer-killing compounds. Playing back the signal with a stronger burst of light will then activate the therapeutic drugs, which kill the cancer cells.

In addition, the technique could offer a way to power miniature implants buried deep within tissues. "If you take a quick survey of what is out there at present, you will see that implants are fairly large," Yang says. "For example, a pacemaker is about the size of a cell phone. Why are they so big? A large part of the reason is because they need to carry their own power sources."

The key to making smaller implants, then--say, the size of a pen tip--is to eliminate the power sources. "I think implants that carry photovoltaic receivers are particularly promising," he says. "The effect can be applied to tailor light-delivery mechanisms to efficiently channel light into tissues and onto these implants."

A study describing the process appears in the February issue of the journal Nature Photonics. Zahid Yaqoob, a postdoctoral fellow in electrical engineering at Caltech, performed most of the experiments reported in the paper. The other authors of the paper are Demetri Psaltis, professor of optics and dean of engineering, École Polytechnique Fédérale de Lausanne in Switzerland, and Michael S. Feld, a professor of physics at MIT.

Adapted from materials provided by California Institute of Technology.

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Daily Science Journal (Feb. 12, 2008) — Turning native ecosystems into "farms" for biofuel crops causes major carbon emissions that worsen the global warming that biofuels are meant to mitigate, according to a new study by the University of Minnesota and the Nature Conservancy.

Aerial view of farmland in Indonesia. The conversion of peatlands for palm oil plantations in Indonesia ran up the greatest carbon debt, one that would require 423 years to pay off. (Credit: iStockphoto)

The carbon lost by converting rainforests, peatlands, savannas, or grasslands outweighs the carbon savings from biofuels. Such conversions for corn or sugarcane (ethanol), or palms or soybeans (biodiesel) release 17 to 420 times more carbon than the annual savings from replacing fossil fuels, the researchers said. The carbon, which is stored in the original plants and soil, is released as carbon dioxide, a process that may take decades. This "carbon debt" must be paid before the biofuels produced on the land can begin to lower greenhouse gas levels and ameliorate global warming.

The conversion of peatlands for palm oil plantations in Indonesia ran up the greatest carbon debt, one that would require 423 years to pay off. The next worst case was the production of soybeans in the Amazon, which would not "pay for itself" in renewable soy biodiesel for 319 years.

"We don't have proper incentives in place because landowners are rewarded for producing palm oil and other products but not rewarded for carbon management," said University of Minnesota Applied Economics professor Stephen Polasky, an author of the study. "This creates incentives for excessive land clearing and can result in large increases in carbon emissions.

"This research examines the conversion of land for biofuels and asks the question 'Is it worth it?'," said lead author Joe Fargione, a scientist for The Nature Conservancy. "And surprisingly, the answer is no."

Fargione began the work as a University of Minnesota postdoctoral researcher with Polasky, Regents Professor of Ecology David Tilman; he completed it after joining the Nature Conservancy. They, along with university researchers Jason Hill and Peter Hawthorne, also contributed to the work.

"If you're trying to mitigate global warming, it simply does not make sense to convert land for biofuels production," said Fargione. "All the biofuels we use now cause habitat destruction, either directly or indirectly. Global agriculture is already producing food for six billion people. Producing food-based biofuel, too, will require that still more land be converted to agriculture."

These findings coincide with observations that increased demand for ethanol corn crops in the United States is likely contributing to conversion of the Brazilian Amazon and Cerrado (tropical savanna). American farmers traditionally rotated corn crops with soybeans, but now they are planting corn every year to meet the ethanol demand and Brazilian farmers are planting more of the world's soybeans. And they're deforesting the Amazon to do it.

The researchers also found significant carbon debt in the conversion of grasslands in the United States and rainforests in Indonesia.

Researchers did note that some biofuels do not contribute to global warming because they do not require the conversion of native habitat. These include waste from agriculture and forest lands and native grasses and woody biomass grown on marginal lands unsuitable for crop production. The researchers urge that all fuels be fully evaluated for their impacts on global warming, including impacts on habitat conversion.

"Biofuels made on perennial crops grown on degraded land that is no longer useful for growing food crops may actually help us fight global warming," said Hill. "One example is ethanol made from diverse mixtures of native prairie plants. Minnesota is well poised in this respect."

"Creating some sort of incentive for carbon sequestration, or penalty for carbon emissions, from land use is vital if we are serious about addressing this problem," Polasky said.

"We will need to implement many approaches simultaneously to solve climate change. There is no silver bullet, but there are many silver BBs," said Fargione. "Some biofuels may be one silver BB, but only if produced without requiring additional land to be converted from native habitats to agriculture."

The work will be published in Science later this month and will be posted online Thursday, Feb. 7.

The work was supported by the University of Minesota's Initiative for Renewable Energy and the Environment and the National Science Foundation.

Adapted from materials provided by University of Minnesota.

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Daily Science Journal (Feb. 12, 2008) — A new study in macaques suggests that antiretroviral drugs used to treat HIV could also protect people from getting the AIDS virus, especially if two drugs are taken in combination before exposure to the virus occurs.

A new study in macaques suggests that antiretroviral drugs used to treat HIV could also protect people from getting the AIDS virus, especially if two drugs are taken in combination before exposure to the virus occurs. (Credit: iStockphoto/Claire George)

The study found that macaques which were repeatedly exposed to SHIV (a virus closely related to HIV) but received antiretroviral drugs were less likely to become infected than exposed macaques that received no anti-HIV medication. The best protection was seen in macaques that had received a combination of two drugs. The study, led by José Gerardo García-Lerma and Walid Heneine from the US Centers for Disease Control and Prevention, is the culmination of a series of experiments designed to show how similar studies in humans -- some of which are planned and in progress -- can be optimally designed.

Although HIV treatment has rapidly advanced since the introduction of antiretroviral drugs in the 1990s, the absence of an effective vaccine means the virus continues to spread, infecting 2.5 million people each year. Pre-exposure prophylaxis (PrEP) -- the prevention of infection by treating people with drugs before they are exposed to the germ in question -- is often used to prevent malaria, but has not yet been shown to be effective against sexual transmission of HIV.

To simulate a common route of HIV transmission in humans, the researchers exposed the macaques to low weekly doses of SHIV that were given rectally. Five groups of macaques were all exposed to the virus in the same way, but they were given different dosages and combinations of antiretroviral drugs. Three groups received drugs daily: the first was only injected with one anti-HIV drug, emtricitabine (FTC); the second group received a daily dose of this drug by mouth in combination with an oral form of another anti-HIV drug called tenofovir; the third was injected with FTC and a high dose of tenofovir every day. A fourth group was also injected with FTC and a high dose of tenofovir, but macaques in this group were only treated shortly before and after the weekly exposures to HIV. For comparison a fifth group of macaques received no anti-HIV drugs.

The results showed that macaques from any of the four groups that received drugs were less likely to become infected than those in the fifth (control) group. All of the macaques receiving the combination of both FTC and the high dosage of tenofovir were protected from infection -- whether they were from the group that received these drugs daily, or only around the time of exposure to infection. The results suggest that higher doses and combinations of drugs worked better than single or low doses, and also that PrEP may not need to be taken every day to be effective.

The researchers also observed some risks that emphasize the need for careful design of human PrEP studies. They found some viral resistance to one of the drugs, FTC, in macaques that became infected. In addition, doses of tenofovir that resulted in maximum protection for macaques are higher than would be safe in humans.

In a related perspective article, Myron Cohen and Angela Kashuba from the University of North Carolina (Chapel Hill, NC, USA), uninvolved with the study, note that the results "highlight an exciting and potentially important use" of antiretroviral drugs to prevent sexual transmission of HIV.

Journal citation: García-Lerma JG, Otten RA, Qari SH, Jackson E, Cong M, et al. (2008) Prevention of rectal SHIV transmission in macaques by daily or intermittent prophylaxis with emtricitabine and tenofovir. PLoS Med 5(2): e28. doi:10.1371/journal.pmed.0050028 http://medicine.plosjournals.org/perlserv/?request=get-document&doi=10.1371/journal.pmed.0050028

Adapted from materials provided by Public Library of Science, via EurekAlert!, a service of AAAS.

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Daily Science Journal (Feb. 12, 2008) — Few modern animals are as deserving of the title “living fossil” as the lowly horseshoe crab. Seemingly unchanged since before the Age of Dinosaurs, these venerable sea creatures can now claim a history that reaches back almost half-a billion years.

Lunataspis aurora - fossil paratype specimen (about 25 mm wide) beside the dried carapace of a young modern horseshoe crab. (Credit: Left image courtesy of G. Young, The Manitoba Museum; right, D. Rudkin, Royal Ontario Museum)

In a collaborative research article published recently in the British journal Palaeontology, a team of Canadian scientists revealed rare new horseshoe crab fossils from 445 million year-old Ordovician age rocks in central and northern Manitoba, which are about 100 million years older than any previously known forms.

Palaeontologist Dave Rudkin from the Royal Ontario Museum, with colleagues Dr. Graham Young of The Manitoba Museum (Winnipeg) and Dr. Godfrey Nowlan at the Geological Survey of Canada (Calgary), gave their remarkable new fossils the scientific name Lunataspis aurora, meaning literally “crescent moon shield of the dawn” in reference to their shape, geological age and northerly discovery sites. Although they are more “primitive” in several aspects than other known horseshoe crabs, their resemblance to living forms is unmistakable.

The fossil horseshoe crabs were recovered in the course of fieldwork studies on ancient tropical seashore deposits, providing yet another important link to their modern descendants that are today found along warmer seashores of the eastern United States and the Indian Ocean.

This is particularly significant, explains Rudkin. “Understanding how horseshoe crabs adapted to this ecological niche very early on, and then remained there through thick and thin, can give us insights into how ocean and shoreline ecosystems have developed through deep time.”

Today, marine shorelines worldwide are being threatened by human activity, and although some horseshoe crab populations are endangered, their enviably long record on Earth indicates that they have successfully weathered many previous crises, including the mass extinction that saw the demise of the dinosaurs and many other life forms 65 million years ago.

“We do need to be concerned about horseshoe crabs and many of the other unusual life forms found on marine shores,” said Dr. Young. “Nevertheless, we can also be mildly optimistic that some of these things have demonstrated a toughness that may allow them to survive our abuse of these environments.”

Living horseshoe crabs are extensively studied, especially in the fields of ecology and medical research. The exciting discovery of these unusual early fossil relatives adds a new introductory chapter to their remarkable story.

David Rudkin is Assistant Curator in the Department of Natural History (Palaeobiology) at the Royal Ontario Museum, and holds an appointment to the Department of Geology, University of Toronto, as a Lecturer in palaeontology. Rudkin joined the former Department of Invertebrate Palaeontology at the ROM in 1975 and began working on fossils from the Burgess Shale in British Columbia.

Adapted from materials provided by Royal Ontario Museum.

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Daily Science Journal (Feb. 11, 2008) — WHO has released new data showing that while progress has been made, not a single country fully implements all key tobacco control measures, and outlined an approach that governments can adopt to prevent tens of millions of premature deaths by the middle of this century. Unless urgent action is taken, tobacco could kill one billion this century.

Cigarette butts. Unless urgent action is taken, tobacco could kill one billion this century, WHO report warns. (Credit: iStockphoto/James Curtis)

Current status of tobacco-related deaths
  • 100 million dead in the 20th century
  • Currently 5.4 million deaths every year
Unless urgent action is taken
  • By 2030, there will be more than 8 million deaths every year
  • By 2030, more than 80% of tobacco deaths will be in developing countries
  • One billion estimated deaths during the 21st century

In a new report which presents the first comprehensive analysis of global tobacco use and control efforts, WHO finds that only 5% of the world’s population live in countries that fully protect their population with any one of the key measures that reduce smoking rates. The report also reveals that governments around the world collect 500 times more money in tobacco taxes each year than they spend on anti-tobacco efforts. It finds that tobacco taxes, the single most effective strategy, could be significantly increased in nearly all countries, providing a source of sustainable funding to implement and enforce the recommended approach, a package of six policies called MPOWER.

“While efforts to combat tobacco are gaining momentum, virtually every country needs to do more. These six strategies are within the reach of every country, rich or poor and, when combined as a package, they offer us the best chance of reversing this growing epidemic,” said Dr Margaret Chan, Director-General of WHO. Dr Chan launched the WHO Report of the Global Tobacco Epidemic at a news conference with New York Mayor Michael Bloomberg. Bloomberg Philanthropies helped fund the report.

“The report released today is revolutionary,” Mayor Bloomberg said. “For the first time, we have both a rigorous approach to stop the tobacco epidemic and solid data to hold us all accountable. No country fully implements all of the MPOWER policies and 80% of countries don’t fully implement even one policy. While tobacco control measures are sometimes controversial, they save lives and governments need to step up and do the right thing.”

The six MPOWER strategies
  • Monitor tobacco use and prevention policies
  • Protect people from tobacco smoke
  • Offer help to quit tobacco use
  • Warn about the dangers of tobacco
  • Enforce bans on tobacco advertising, promotion and sponsorship
  • Raise taxes on tobacco
The report also documents the epidemic's shift to the developing world, where 80% of the more than eight million annual tobacco-related deaths projected by 2030 are expected to occur.

This shift, the report says, results from a global tobacco industry strategy to target young people and adults in the developing world, ensuring that millions of people become fatally addicted every year. The targeting of young women in particular is highlighted as one of the “most ominous potential developments of the epidemic’s growth".

The global analysis, compiled by WHO with information provided by 179 Member States, gives governments and other groups a baseline from which to monitor efforts to stop the epidemic in the years ahead. The MPOWER package provides countries with a roadmap to help them meet their commitments to the widely embraced global tobacco treaty known as the WHO Framework Convention on Tobacco Control, which came into force in 2005.

WHO is also working with global partners to scale up the help that can be offered to countries to implement the strategies.

Dr Douglas Bettcher, Director of WHO’s Tobacco Free Initiative, said the six MPOWER strategies would create a powerful response to the tobacco epidemic. “This package will create an enabling environment to help current tobacco users quit, protect people from second-hand smoke and prevent young people from taking up the habit,” he said.

Other key findings in the report
  • Only 5% of the global population is protected by comprehensive national smoke-free legislation and 40% of countries still allow smoking in hospitals and schools;
  • Only 5% of the world’s population lives in countries with comprehensive national bans on tobacco advertising and promotion;
  • Just 15 countries, representing 6% of the global population, mandate pictorial warnings on tobacco packaging;
  • Services to treat tobacco dependence are fully available in only nine countries, covering 5% of the world’s people;
Tobacco tax revenues are more than 4000 times greater than spending on tobacco control in middle-income countries and more than 9000 times greater in lower-income countries. High- income countries collect about 340 times more money in tobacco taxes than they spend on tobacco control.

PDF of full report: http://www.who.int/entity/tobacco/mpower/mpower_report_full_2008.pdf

Adapted from materials provided by World Health Organization.

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Daily Science Journal (Feb. 11, 2008) — In a study of pregnant women, those with pregnancy-induced high blood pressure were found to have higher levels of a peptide that raises blood pressure in the pieces of tissue linking mother and fetus, according to researchers at Wake Forest University Baptist Medical Center. The finding, reported online in the journal Hypertension, may help explain how the disorder develops.

Preeclampsia, or high blood pressure induced by pregnancy, affects 7 to 10 percent of pregnancies in the United States and is the second-leading cause of maternal mortality. It is the leading cause of pre-term delivery and contributes significantly to stillbirths and death in newborns.

The researchers found that in women with preeclampsia, levels of angiotensin II (Ang II), a hormone that constricts blood vessels and causes blood pressure to rise, was doubled in the chorionic villi, part of the placenta that links mother and fetus and supplies food and oxygen.

"This finding may be part of the preeclampsia puzzle," said Lauren Anton, a graduate student who is first author on the research. "Anything that gets us closer to understanding this disease is important because there is no treatment and no cure and women are still delivering babies too early."

The researchers theorize that Ang II may restrict the fetal vessels that lie within the chorionic villi, which not only raises blood pressure, but also lowers oxygen and nutrient flow to the baby and may result in lower birth weight and other complications of preeclampsia.

The study involved 21 women with preeclampsia and 25 women without the disorder. After delivery, tissue sections were taken from the center of the placenta for analysis.

Ang II is part of the renin angiotensin system (RAS) that regulates blood pressure. The system has been shown to play an important role in preeclampsia. However, changes in the system also occur in women who don't develop the condition. In normal pregnancies, estrogen causes increased levels of several hormones, including Ang II, in the blood. Despite the increase of Ang II in the blood during pregnancy, most women do not develop preeclampsia.

This the first study to demonstrate that all three peptides involved in the RAS are found in the chorionic villi of both normal and preeclamptic women. And, it was the first to show that levels of Ang II are higher in the chorionic villi of women with preeclampsia.

"This implies that local tissues are contributing to the problem," said K. Bridget Brosnihan, Ph.D., senior researcher, who has been studying preeclampsia for 12 years. "The hormone is remarkably elevated in this relatively small tissue, which implies that it has an important role in the development of preeclampsia."

The researchers hope that the findings may one day lead to treatment for preeclampsia.

ACE inhibitor drugs are currently used to lower Ang II in non-pregnant women with hypertension, but these drugs cannot be given to pregnant women. The study authors suggest that other therapies aimed at regulating blood pressure might be beneficial if they target the chorionic villi rather than the system as a whole. They are currently working to determine if growth factors that cause the placenta's blood supply to develop may also be regulated by the increase in Ang II.

The study was supported, in part, by the National Institutes of Health and the American Heart Association. It was published in the Go Red issue of Hypertension that is dedicated to women's cardiovascular health.

Co-researchers are David Merrill, M.D., Ph.D., Liomar Neves, Ph.D., Kathryn Stovall, B.S., Patricia Gallagher, Ph.D., Debra Diz, Ph.D., Cheryl Moorefield, R.N., Courtney Gruver, R.N., and Carlos Ferrario, M.D., all with Wake Forest.

Adapted from materials provided by Wake Forest University Baptist Medical Center, via EurekAlert!, a service of AAAS.

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