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Polymorphism Of An Opioid Receptor Linked To Alcohol Misuse Among AdolescentsA genetic study has examined the association between a polymorphism of the µ-opioid receptor (OPRM1) gene and alcohol misuse among adolescents. Results suggest that teens who carry the G allele (A118G) of the OPRM1 gene are at increased risk for alcohol problems because they experience alcohol as more pleasurable or rewarding than teens without A118G.Source: ScienceDaily: Latest Science News | 29 Oct 2009 | 12:00 pm Knocking Nanoparticles Off The SocksScientists are reporting results of one of the first studies on the release of silver nanoparticles from laundering those anti-odor, anti-bacterial socks now on the market. Their findings may suggest ways that manufacturers and consumers can minimize the release of these particles to the environment, where they could harm fish and other wildlife.Source: ScienceDaily: Latest Science News | 29 Oct 2009 | 12:00 pm Genes That Drive You To Drink (But Don't Make You An Alcoholic)Your genetic make up may predispose you to drink more but may not increase your genetic risk for alcoholism. New research pinpoints genetic pathways and genes associated with levels of alcohol consumption but not with alcohol dependence in rats and humans.Source: ScienceDaily: Latest Science News | 29 Oct 2009 | 12:00 pm Pumpkin Skin May Scare Away GermsThe skin of that pumpkin you carve into a Jack-o'-Lantern to scare away ghosts and goblins on Halloween contains a substance that could put a scare into microbes that cause millions of cases of yeast infections in adults and infants each year, according to a new study.Source: ScienceDaily: Latest Science News | 29 Oct 2009 | 12:00 pm Blast From The Past Gives Clues About Early UniverseAstronomers studied the most distant object yet seen in the Universe, a giant stellar blast from more than 13 billion years ago, and learned tantalizing facts about the blast itself and the environment of the star that exploded in the early Universe.Source: ScienceDaily: Latest Science News | 29 Oct 2009 | 12:00 pm Use Of Antipsychotic Medications By Children And Adolescents Associated With Significant Weight GainMany pediatric and adolescent patients who received second-generation antipsychotic medications experienced significant weight gain, along with varied adverse effects on cholesterol and triglyceride levels and other metabolic measures, according to a new study.Source: ScienceDaily: Latest Science News | 29 Oct 2009 | 12:00 pm Circadian Surprise: Mechanism Of Temperature Synchronization In DrosophilaNew research reveals a pathway that links peripheral sensory tissues with a "clock" in the brain to regulate molecular processes and behaviors in response to cyclical temperature changes. The research reveals some surprising fundamental differences between how light-dark and temperature cycles synchronize the brain clock of the fruit fly, Drosophila.Source: ScienceDaily: Latest Science News | 29 Oct 2009 | 9:00 am Answering That Age-old Lament: Where Does All This Dust Come From?Where does it come from? Scientists are reporting a surprising answer to that question, which has puzzled and perplexed generations of men and women confronted with layers of dust on furniture and floors. Most of indoor dust comes from outdoors.Source: ScienceDaily: Latest Science News | 29 Oct 2009 | 9:00 am Stem Cells Changed Into Precursors For Sperm, EggsHuman embryonic stem cells derived from excess IVF embryos may help scientists unlock the mysteries of infertility for other couples struggling to conceive, according to new research. Researchers at the school have devised a way to efficiently coax the cells to become human germ cells -- the precursors of egg and sperm cells -- in the laboratory.Source: ScienceDaily: Latest Science News | 29 Oct 2009 | 9:00 am Migraine With Aura Doubles Risk Of StrokeMigraine with aura (temporary visual or sensory disturbances before or during a migraine headache) is associated with a twofold increased risk of stroke, finds a new study. Further risk factors for stroke among patients with migraine are being a woman, being young, being a smoker and using estrogen-containing contraceptives.Source: ScienceDaily: Latest Science News | 29 Oct 2009 | 9:00 am EU leaders to discuss EU presidency, climate change (AFP)
Source: Yahoo! News: Science News | 29 Oct 2009 | 4:26 am Ghostly 'dance of a sea dragon'The dance of the weedy sea dragon, one of the most elegant courtship rituals in the animal kingdom, is filmed by a BBC crew.Source: BBC News | Science & Environment | UK Edition | 29 Oct 2009 | 3:48 am The nation's weather (AP)
Source: Yahoo! News: Science News | 29 Oct 2009 | 3:44 am US, China huddle for high-level trade talks (AFP)
Source: Yahoo! News: Science News | 29 Oct 2009 | 3:19 am Accused spy scientist due in court (AP)AP - A space exploration scientist accused of attempted espionage is scheduled to appear in court to learn whether he will have to stay behind bars while he awaits trial.Source: Yahoo! News: Science News | 29 Oct 2009 | 1:09 am Bad driver? Blame your genesWASHINGTON (Reuters) - No need to curse that bad driver weaving in and out of the lane in front of you -- he cannot help it, U.S. researchers reported on Wednesday.Source: Reuters: Science News | 28 Oct 2009 | 11:33 pm Bad driver? Blame your genes (Reuters)
Source: Yahoo! News: Science News | 28 Oct 2009 | 11:33 pm Scientists see blast from past -- 13 billion years agoWASHINGTON (Reuters) - Astronomers have seen the furthest back in time ever, measuring light from a star that exploded 13 billion years ago, just after the dawn of the universe.Source: Reuters: Science News | 28 Oct 2009 | 11:20 pm Size matters when it comes to AIDS defenseWASHINGTON (Reuters) - Men with larger foreskins are more likely to become infected with the AIDS virus, researchers said Wednesday in a finding that helps explain why circumcision can protect men.Source: Reuters: Science News | 28 Oct 2009 | 11:17 pm How to Avoid the FDIC Email Scam (LiveScience.com)LiveScience.com - A mass phishing email scheme aims to steal banking information under the guise of the FDIC, just the most recent in a long line of scams, bilking millions from consumers.Source: Yahoo! News: Science News | 28 Oct 2009 | 11:06 pm Windows 7: Beyond the HooplaWindows users will now have to figure out how to adjust to the latest version.Source: Livescience.com | 28 Oct 2009 | 10:19 pm The Future of Video Game Input: Muscle SensorsA muscle computer interface allows interaction with a computer without touching an keyboard, mouse or other input device.Source: Livescience.com | 28 Oct 2009 | 10:11 pm Repairing Injured Lungs May Boost Organ Donations (HealthDay)HealthDay - WEDNESDAY, Oct. 28 (HealthDay News) -- A new type of gene therapy for injured lungs that were previously rejected for transplantation may increase the number of lungs available for transplant, researchers say.Source: Yahoo! News: Science News | 28 Oct 2009 | 9:49 pm SpacemanNasa's new rocket flies - but where is it going?Source: BBC News | Science & Environment | UK Edition | 28 Oct 2009 | 6:54 pm Tuna ban 'justified' by scienceBanning trade in Atlantic bluefin tuna is justified by the extent of their decline, scientists advising fisheries regulators suggest.Source: BBC News | Science & Environment | UK Edition | 28 Oct 2009 | 6:36 pm NASA's New Rocket Sports a Supersonic Look (SPACE.com)SPACE.com - NASA's gleaming new Ares I-X rocket grew an odd-looking hood Wednesday as it launched skyward on a suborbital test flight — a telltale sign of a rocket going supersonic.Source: Yahoo! News: Science News | 28 Oct 2009 | 5:21 pm Birds Use Light, Not Magnetic Field, to Migrate
A cell in the eye may be worth two in the beak, at least when it comes to a migratory bird’s magnetic compass. In European robins, a visual center in the brain and light-sensing cells in the eye — not magnetic sensing cells in the beak — allow the songbirds to sense which direction is north and migrate correctly, a new study finds. The study, appearing Oct. 29 in Nature, may improve conservation efforts for migratory birds.
Researchers have known that built-in biological compasses tell migrating birds which way to fly, but the details of how birds detect magnetic fields has been unclear. “This is basically the sixth sense of biology, but no one knows how it works,” says study co-author Henrik Mouritsenof the University of Oldenburg in Germany. “The magnetic sense is by far the least-understood sense in the natural world.” Some researchers had proposed that iron-based receptors in cells found in the upper beaks of some migratory birds sense the magnetic field and send that information along a nerve to the brain. Other scientists favor the hypothesis that light-sensing cells in birds’ eyes sense the magnetic field and send the information along a different route to a light-processing part of the brain called cluster N. Special proteins called cryptochromes in the birds’ eyes may mediate this light-dependent magnetic sensing, Mouritsen says. Light hitting the proteins produces a pair of free radicals, highly reactive molecules with unpaired electrons. These electrons have a property called spin which may be sensitive to Earth’s magnetic field. Signals from the free radicals may then move to nerve cells in cluster N, ultimately telling the birds where north is.
To find the location that houses the magnetic compass, Mouritsen and his colleagues caught 36 migratory European robins and made sure that the birds could all orient correctly under natural and induced magnetic fields. Next, the researchers performed surgeries on the birds to deactivate one of the two systems. The team either severed the nerve that connects the beak cells to the brain, or damaged the brain cells in cluster N that receive light signals from cells in the eye. Birds with the severed beak-to-brain nerve — called the trigeminal nerve — still oriented perfectly, Mouritsen says. “No information from those iron crystals could get to the brain, but the birds oriented just as well,” he says, suggesting that the beak cells are not important for orientation. On the other hand, birds with damaged cluster N regions could no longer sense and orient to magnetic fields. These robins failed to pick up both the Earth’s natural magnetic field and the artificial fields created by the researchers. The new study “nicely confirms that the trigeminal nerve is not involved in this direction sensing,” says John Phillips, a neuro-ecologist at Virginia Tech in Blacksburg. “This is an important advance in what we know about these systems.” Mouritsen thinks the cells in the beak might play a different role in magnetic sensing, such as picking up minor changes in the strength of the magnetic field along a north-south axis, he says. Understanding more about how birds navigate and sense the environment may have important conservation implications, Mouritsen says. Migratory birds that humans have relocated often fly back to the original migratory grounds. But if researchers can figure out how the birds navigate, conservationists may be able to trick the birds into staying where it’s safe. See Also:
Source: Wired: Wired Science | 28 Oct 2009 | 4:31 pm BLOG: Frankenfood? Transgenes Run WildTake a closer look at the unexpected consequences of genetically modified crops.Source: Discovery News Top Stories : Discovery Channel | 28 Oct 2009 | 4:30 pm BLOG: Is Windows 7 Right for You?XP loyalists may have a hard time letting go of their trusted operating system.Source: Discovery News Top Stories : Discovery Channel | 28 Oct 2009 | 4:00 pm Swimming Pools Kept Clean by Going GreenTreating pools with moss can not only keep water clean, but also reduce maintenance costs.Source: Discovery News Top Stories : Discovery Channel | 28 Oct 2009 | 3:35 pm One embryo nearly as good a multiples for pregnancyBOSTON (Reuters) - Women who initially receive just one embryo during in vitro fertilization are as likely to produce a child as women implanted with two, Swedish researchers reported on Wednesday.Source: Reuters: Science News | 28 Oct 2009 | 3:22 pm 2012 Cataclysm: Ancient Astronomy to Modern Myth?Our skeptic, Ben Radford, takes on three authors to calibrate the claims of planetary disaster in 2012.Source: Livescience.com | 28 Oct 2009 | 3:21 pm Scientists make cells that form eggs and sperm in labCHICAGO (Reuters) - U.S. researchers have found a way to coax human embryonic stem cells to turn into the types of cells that make eggs and sperm, shedding light on a stage of early human development that has not been fully understood.Source: Reuters: Science News | 28 Oct 2009 | 3:17 pm Study: Bad Driving Is GeneticBad driving could be in your genes.Source: Livescience.com | 28 Oct 2009 | 3:15 pm How to Avoid the FDIC Email ScamEmail scams are rampant, but there is a simple way to avoid being scammed.Source: Livescience.com | 28 Oct 2009 | 2:49 pm NASA's new moon rocket makes first test flight (AP)
Source: Yahoo! News: Science News | 28 Oct 2009 | 2:13 pm Culture (Not Just Genes) Drives EvolutionCultural differences have manifested themselves in the DNA of distinct, regional groups.Source: Discovery News Top Stories : Discovery Channel | 28 Oct 2009 | 2:10 pm Former CEO sentenced 3 years for Alaska bribery (Reuters)Reuters - The businessman at the center of Alaska's wide-ranging political corruption investigation, once a pillar of the Alaska oil industry and state Republican party, was sentenced on Wednesday to serve three years in prison and to pay a $750,000 fine.Source: Yahoo! News: Science News | 28 Oct 2009 | 1:54 pm Making Molecules (And Salamanders) GlowChemist uses fluorescent proteins to light up science.Source: Livescience.com | 28 Oct 2009 | 1:46 pm NASA successfully tests new tall moon rocketCAPE CANAVERAL, Florida (Reuters) - An unmanned NASA rocket designed to help develop a new space taxi service to the moon streaked through the sky on Wednesday on a successful two-minute test flight.Source: Reuters: Science News | 28 Oct 2009 | 1:33 pm 40 Years Ago: The Message that Conceived the InternetThursday marks 40 years since the first message was sent over a network that would later become the Internet.Source: Livescience.com | 28 Oct 2009 | 1:06 pm Baffling Patterns Form in Scientific SandboxWith nothing more than beads in a glass box, physicists have revealed yet another mysterious property of granular solids, now recognized by scientists as a unique state of matter, like solids or gases. When the box was filled to the brim and rotated, the beads moved in patterns known from convection clouds — another system whose basic physical dynamics are only dimly understood. The experiment, displayed in a video posted Monday to arXiv, was a variation on one performed 70 years ago by Japanese physicist Yositsi Oyama, who observed that beads of different sizes placed in a rotating circular drum would eventually self-sort by size. That intriguing result set in motion the study of granular solids, which behave in ways that can’t be predicted with known physical laws. And though research has accelerated in the last decade, scientific understanding of granularity is roughly akin to that of fluid dynamics in the 18th century. In the latest experiment, conducted by Otto von Guericke University physicists Ralf Stannarius and Frank Rietz, a partially full rotating box of beads displayed the self-sorting patterns seen by Oyama. But when they filled the box nearly to the top — which, they expected, would cause the beads to clog — the beads instead moved in graceful, swirling currents.
Why this should happen is unclear. No equations exist to describe why such a slight change in packing density should produce such different system-wide behavior. “Known mechanisms for granular convection could not be applied,” wrote Rietz and Stannarius. Intriguingly, similar currents can be seen in clouds, or ocean currents. In a paper published last February in Physical Review Letters, the pair described the mysterious movements of beads in their box as suggesting “the existence of comparable phenomena in situations where so far no systematic search for dynamic patterns has been performed.” Image and video: Frank Rietz and Ralf Stannarius See Also:
Citations: 1) “Convection rolls in a rotating box filled with beads.” By Frank Rietz and Ralf Stannarius. arXiv, October 26, 2009. 2) “On the Brink of Jamming: Granular Convection in Densely Filled Containers.” By Frank Rietz and Ralf Stannarius. Physical Review Letters, Vol. 100 Issue 7, February 20, 2009. Brandon Keim’s Twitter stream and reportorial outtakes; Wired Science on Twitter. Brandon is currently working on a book about ecosystem and planetary tipping points.
Source: Wired: Wired Science | 28 Oct 2009 | 1:00 pm Stellar blast is record-breakerA huge explosion known as a gamma ray burst is confirmed as the most distant cosmic event seen from Earth.Source: BBC News | Science & Environment | UK Edition | 28 Oct 2009 | 12:47 pm Pumpkins Pack Natural Fungus FighterScientists have found a new anti-fungal protein in pumpkin skin, a new study saysSource: Livescience.com | 28 Oct 2009 | 12:33 pm Climate Change Caused Radical North Sea Shift
Fueled by previously unappreciated links between climate and ecology, the North Sea has undergone a radical ecological shift in the last half-century, say scientists. The very shape of the food web has changed, from plankton on up to the cod and flatfish that once dominated the icy waters, supporting rich commercial fisheries. They’ve been largely replaced by jellyfish and crabs. The full scope of the change has gone relatively unnoticed, and could foreshadow changes in waters around the world. “Climate-driven changes in the biology of the sea are largely hidden from view,” said Richard Kirby, a marine biologist at the University of Plymouth. “If similar changes occurred in a temperate forest, we would be shocked.”
In a study published in the upcoming December Proceedings of the Royal Society B, Kirby and Gregory Bertrand, an oceanologist at the Lille University of Science and Technology, analyze decades of climate and ecosystem data gathered in the North Sea, a pocket of ocean bordered by the United Kingdom and Scandinavia. Though relatively small, the North Sea has historically been a fabulously fertile fishing ground. Even now, it provides about five percent of the global fish harvest — but that’s barely a third of what it yielded just a century ago. Declining stocks have been blamed almost entirely on overfishing. However, though fishing pressures have indeed been intense, some scientists have suspected that water temperatures are also a factor. Over the last quarter-century, the North Sea’s upper layers have warmed by about 1 degree Fahrenheit. That seems like little, but in the North Sea, summer and winter water temperatures differ by just a few degrees. Even a single degree of change is relatively profound, and enough to disrupt aquatic organisms accustomed to functioning in a very narrow thermal range. Whether the warming is man-made or not, it’s a sign of times to come. Global ocean temperatures are expected to experience a comparable or greater rise during the next century. And the consequences, as anticipated by the North Sea, have been relatively unacknowledged. Most discussions of climate change impacts focus on the terrestrial. When ocean life is mentioned, it’s in the context of of coral reef bleaching or acidifying waters. Both those threats are grave, but the possibility of oceans completely changing their character, independent of acidification or reef effects, may be just as troubling. “The effect of climate on the marine food web, the way small changes can be amplified through the web, that’s the moral of the story here,” said Kirby. “And food webs everywhere will be affected in a similar way.” At the heart of Kirby and Bertrand’s findings is data from the Continuous Plankton Recorder Survey, which has been run in the North Atlantic since 1931, when explorer Alister Hardy invented the recorder — a specialized box that’s dragged behind commercial ships, allowing researchers to take sea-wide samples of plankton and juvenile members of other species. Combined with temperature records, the CPRS provides the most comprehensive climate-ecosystem dataset of any ocean, if not the entire world. And as temperatures have changed, so has every part of the food web, starting with its foundation. “If you were to divide zooplankton into those that prefer warmer southern waters, and those that prefer colder northern waters, and look at the boundaries between those groups, it’s moved north by over 700 miles in the last 40 years,” said Kirby. “That’s one of the largest range shifts, if not the largest, that’s been recorded.”
“The North Sea has fundamentally changed. It’s a totally different ecosystem from what it was,” said Kirby. When Kirby and Bertrand crunched the numbers describing these patterns with equations designed to separate cause from coincidence, they found that temperature drove the changes. They also found evidence for what they call “trophic amplification.” “Because temperature acts on different components of the food web, the gross effect is amplified,” said Kirby. “It affects the phytoplankton that copepods feed on; it affects the copepods; it affects the predators who eat the copepods; and all those effects, magnified, are much greater than any one alone.” This compounding dynamic is responsible for the extreme rapidity of the shift, he added. “The findings seem plausible to me,” said Marten Scheffer, a Wageningen University ecologist who specializes in ecosystem-wide transitions. Scheffer, who was not involved in the study, also said that marine shifts are notoriously difficult to study. “Compared to work on lakes, or terrestrial grazing systems, there is little scope for experimental testing,” he said. According to Kirby, models by fisheries managers need to incorporate these dynamics and and policymakers contemplating global warming need to consider the magnitude of the change. A similar dynamic may be at work in the Sea of Japan, which in recent years has become dominated by giant jellyfish. “Marine ecosystems have always changed, but people don’t realize how responsive they are, and how rapidly they may change,” he said. “Humans shouldn’t forget that we don’t live in isolation from the food web.” Images: 1. Flickr/PhillipC 2. A model of North Sea ecosystem dynamics, from Richard Kirby and Gregory Bertrand. See Also:
Citation: “Trophic amplification of climate warming.” By Richard R. Kirby and Gregory Beaugrand. Proceedings of the Royal Society B, Vol. 276 No. 1676, December 7, 2009. Brandon Keim’s Twitter stream and reportorial outtakes; Wired Science on Twitter. Brandon is currently working on a book about ecosystem and planetary tipping points.
Source: Wired: Wired Science | 28 Oct 2009 | 12:28 pm Google Releases Free Turn-by-Turn Navigation AppGoogle announced a free navigation app that gives turn-by-turn navigation through the Google Maps interface.Source: Livescience.com | 28 Oct 2009 | 12:26 pm Violent Explosion Is Most Distant Object Ever SeenNew gamma-ray burst becomes most distant object yet seen, could shed light on early universe.Source: Livescience.com | 28 Oct 2009 | 12:12 pm Stem cell study leads to fertility breakthrough'Hidden stage of human development' is opened up by Stanford University scientists Scientists have turned human stem cells into early-stage sperm and eggs in research that promises to give doctors an unprecedented insight into the causes of infertility. The work will allow researchers to study human reproductive cells from the moment they are created in embryos through to fully-mature sperm and eggs. Understanding the details of how sperm and egg cells grow will help scientists develop treatments for people who are left infertile when the process goes wrong. The research may also lead to treatments that can correct growth defects before a child is born. Genetic glitches that happen early on in the growth of sperm and eggs are a major cause of infertility in men and women. The process has been practically impossible to study until now though, because the sex cells form early on, before an embryo is two weeks old. "This achievement opens a new window into what was only recently a hidden stage of human development," said Susan Shurin at the National Institute of Child Health and Human Development, which part funded the research. A team led by Renee Reijo Pera at Stanford University in California developed a technique that turned human embryonic stem cells green when they started growing into sperm and eggs. After isolating the reproductive cells, the scientists worked out which genes made them grow properly by switching different genes on and off. Writing in the journal Nature, the scientists describe how that one gene, called DAZL, is involved in the formation of sex cells from the start. Two related genes are switched on later to steer the cells to full maturity. The main significance of the work is not to attempt to generate gametes for couples who do not produce them naturally. Rather, the work describes a system in which various aspects of germ cell development can be studied in a dish. In the current study, they have gained insight into the function of three genes in which they specialise." Darren Griffin, a geneticist at the University of Kent, said the work was important because it gave researchers a way to study human sperm and egg development in a dish, instead of having to rely on tissues taken from animals or "removing bits of people's gonads". "In future, a range of genetic and environmental factors could be studied, including the effects of pollutants on our fertility. Only through understanding such factors at a basic scientific level can we hope to develop novel diagnoses and therapies. The potential is enormous," he said. Allan Pacey, an andrologist at Sheffield University, said: "Ultimately this may help us find a cure for male infertility. Not necessarily by making sperm in the laboratory – I personally think that it unlikely – but by identifying new targets for drugs or genes that may stimulate sperm production to occur naturally. This is a long way off, but it is a laudable dream. guardian.co.uk © Guardian News & Media Limited 2009 | Use of this content is subject to our Terms & Conditions | More Feeds Source: Science news, comment and analysis | guardian.co.uk | 28 Oct 2009 | 12:00 pm Happy National Chocolate DayCelebrate the history, the culture, the health benefits and certainly the taste of chocolate.Source: Discovery News Top Stories : Discovery Channel | 28 Oct 2009 | 12:00 pm NASA Rocket Scientists Did ‘Frickin’ Fantastic’Nothing gets the NASA boys fired up quite like a rocket launch. The Ares I-X rocket, a modified prototype of the Ares I rocket that may send humans back to the moon, and the 2.6 million pounds of thrust it put out, sent the engineers at Kennedy Space Center at Cape Canaveral into paroxysms of joy. “You all did frickin’ fantastic,” said Ed Mango, the new launch director at Kennedy, shortly before having his tie cut just above the navel by the director of Kennedy, Bill Parsons. The tie-cutting is an old tradition borrowed from the Air Force — and it matched the back-to-the-future mood of the event perfectly. All the giddiness comes at an odd time for Ares I, and the Constellation program of which it’s a part. An Obama-requested review of NASA’s plans for human spaceflight wrapped up its work last week with a thumbs-down for the Ares I. “I got tears in my eyes. All the naysayers …” said Parsons, before breaking off and continuing along a more positive line. “That was just one of the most beautiful rocket launches I’ve ever seen.” The NASA engineers are also looking to get some real data from the 700 sensors aboard the vehicles to test their models of how the new rocket is supposed to behave. “The most valuable learning is through experience and observation,” said Bob Ess, Ares I-X mission manager, in a release. “Tests such as this — from paper to flight — are vital in gaining a deeper understanding of the vehicle, from design to development.”
Image: flickr/Matthew Simantov See Also:
WiSci 2.0: Alexis Madrigal’s Twitter, Google Reader feed, and green tech history research site; Wired Science on Twitter and Facebook.
Source: Wired: Wired Science | 28 Oct 2009 | 11:48 am Doctors Kill Parasitic Worms By Poisoning the Bacteria in Their Innards
In some African villages, nearly everyone is infected with Mansonella perstans, a parasitic worm that’s remarkably hard to kill. It’s resistant to standard anti-worm medications, but researchers have learned that an old antibiotic can vanquish the tiny beasts — in a roundabout way. The parasites are stuffed with a type of bacteria called wolbachia, and apparently they depend upon those microbes for their own survival. By killing the bacteria inside of the worms, doctors can destroy the worms themselves. To test that concept, an international team recruited volunteers with M. Perstans infections from four villages in Mali, and gave 69 of them a dose of doxycycline each day. After one year, all but two of the patients who took the antibiotic were free from worms in their blood. “Doxycycline is the first drug that has been shown to be effective in clearing Mansonella perstans parasites from the blood of infected people,” said Amy Klion, a doctor at the National Institutes of Health who led the study. “The fact that the parasites were not detectable in the blood 3 years after the 6 week treatment suggests that doxycycline also had an effect on the adult worms, which live in the tissues surrounding the lungs, heart and abdomen.” Roughly 120 million people worldwide are infected with filarial parasites. Many of those worms will fall after a single dose of albendazole and ivermectin, but M. Perstans is too tough for both drugs. Thankfully, it’s far less destructive than other types of nematodes. It usually results in itching, fatigue, and dermatitis.
Wolbachia have proven to be the Achilles’ heel of nastier parasites too. Before Klion and her team showed that doxycycline can be used to treat the annoying worm infections, other doctors learned that it is an effective way to eliminate their nasty cousins, the parasites that cause elephantiasis and river blindness. Despite the success of those treatments, nobody knows for sure why the worms and bacteria are interdependent. “The basis of the endosymbiosis between wolbachia endosymbionts and their wormy hosts is currently not understood.,” wrote Achim Hoerauf, a doctor at the Bonn University Clinic in a commentary for the New England Journal of Medicine. “Some conclusions can be drawn from the fact that worms lack essential genes for certain metabolic pathways that are present in wolbachia, and vice versa.” Hoerauf suggested that the treatment might not work everywhere. In other parts of Africa, researchers have found worms that can live without wolbachia. Despite that concern, he is convinced that the antibiotic will work in some parts of the world. When the infectious disease expert emailed us, he was on his way to distribute the antibiotic in Ghana. At less than two dollars for a six-month supply. Doxycycline is a bargain for nongovernment organizations. But they might not buy it for the purpose of eliminating M. Perstans. “Doxycycline is not very easy to administer as a mass drug treatment since it absolutely cannot be given to pregnant women or children under the age of 12 because of effects on developing teeth and bones,” said Klion. “Second, courses shorter than 4 weeks have not been very effective in other filarial infections, and this is a very impractical for mass administration.” Because the symptoms of M. Perstans infections are pretty mild, Hoerauf doubts that charities will try to eradicate it with doxycycline. But he thinks that the versatile drug will be used to treat many cases of river blindness. Citation: A Randomized Trial of Doxycycline for Mansonella perstans Infection, New England Journal of Medicine, 361, 2009 Photo: DraconianRain / flickr See Also:
Source: Wired: Wired Science | 28 Oct 2009 | 11:13 am In picturesAn inventory of species threatened by climate changeSource: BBC News | Science & Environment | UK Edition | 28 Oct 2009 | 10:30 am Scientists say curry compound kills cancer cellsLONDON (Reuters) - A molecule found in a curry ingredient can kill esophageal cancer cells in the laboratory, suggesting it might be developed as an anti-cancer treatment, scientists said on Wednesday.Source: Reuters: Science News | 28 Oct 2009 | 10:15 am Ares Rocket Lifts Off in Short Test FlightNASA's newest rocket resembled a giant white pencil as it shot into the sky.Source: Discovery News Top Stories : Discovery Channel | 28 Oct 2009 | 10:10 am Nasa launches Ares 1-X rocket on first flightRocket designed to replace ageing space shuttle blasts off from Florida on unmanned two-minute test flight Nasa is celebrating the inaugural flight of its giant Ares 1-X rocket despite concerns that the White House may scrap the launcher because it costs too much. The slender 100m-tall rocket, which is designed to replace the ageing space shuttle, blasted off at 11.30am local time from the Kennedy Space Centre in Florida. The $455m unmanned test flight gave Nasa staff the opportunity to monitor the new rocket's performance and hardware systems as it soared to an altitude of about 28 miles in two minutes before falling back into the Atlantic. The demonstration flight marks a critical milestone in Nasa's plans to develop the Ares rocket as a replacement for the space shuttle, which is due to retire as early as next year. The launch took place after poor weather frustrated launch attempts yesterday. Grounding the shuttle fleet will free up funds to complete the Ares rocket programme but will leave astronauts from America, Europe and elsewhere reliant on the Russian Soyuz rocket for a ride to the international space station. Nasa has developed two versions of the Ares launcher. One will carry the crew into space, while the other will lift their equipment and supplies to a rendezvous point in orbit. The rockets are the workhorses of Nasa's Constellation programme, which aims to give the agency the capability to ferry astronauts to the international space station and return humans to the moon by 2020. The Ares rocket is tentatively scheduled to be in service by 2015 but an influential review of Nasa's human spaceflight programme has cast doubt on its future. The Augustine panel questioned the cost, design and construction schedule of the rocket in a report submitted to the White House for consideration. Ares is the first new design to emerge from Nasa in 30 years and is the largest ever designed and built by the space agency. The rocket used in the test flight is identical to the one Nasa hopes to use to lift astronauts into space, except for the top half, which included a dummy crew capsule and upper-stage rocket. During the flight it was estimated to have reached a speed of nearly five times the speed of sound. Both lower and upper stages of the rocket will be retrieved by ships that will track them using radar. guardian.co.uk © Guardian News & Media Limited 2009 | Use of this content is subject to our Terms & Conditions | More Feeds Source: Science news, comment and analysis | guardian.co.uk | 28 Oct 2009 | 9:45 am Nasa rocket launches successfullyThe US space agency has launched the Ares I-X, a prototype rocket designed to replace the ageing shuttle.Source: BBC News | Science & Environment | UK Edition | 28 Oct 2009 | 9:32 am Digital 'Ants' Take on Computer WormsDigital "ants" wander through computers searching out and then swarming viruses and worms.Source: Discovery News Top Stories : Discovery Channel | 28 Oct 2009 | 8:00 am Volcanic Air Pollution Chokes LocalsLiving near volcanoes exposes people to subtle lung damage due to volcanic air.Source: Discovery News Top Stories : Discovery Channel | 28 Oct 2009 | 6:00 am Starfish 'pump up' to cool downStarfish have a remarkable strategy to avoid overheating in the sun, according to new research.Source: BBC News | Science & Environment | UK Edition | 28 Oct 2009 | 5:57 am 1507 gagHow America was named by this map... and a punSource: BBC News | Science & Environment | UK Edition | 28 Oct 2009 | 5:40 am Have you seen Crinkly? The search for a wobbly-necked swanA wildlife charity asks the public to watch for the arrival of a special swan called Crinkly, who survives despite a disability.Source: BBC News | Science & Environment | UK Edition | 28 Oct 2009 | 4:09 am
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