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Prolonged Computer Use Means
Immobility Leading to DVT (Go To Top) LONDON: A new study has revealed that working in front of the computer for long hours could increase the risk of developing potentially deadly blood clots, called deep vein thrombosis (DVT), according to a report in the European Respiratory Journal. The report stated the case of a young man from New Zealand who nearly died after developing the disease after sitting in front of his computer for a long time. The man, the first recorded victim of a condition which has been dubbed e-thrombosis, spent up to 18 hours a day using his computer, according to experts. He developed a massive blood clot that formed in his leg veins, broke off and travelled to his lungs. Although the controversy about long-haul air travel has recently put DVT in the headlines, the condition was first described in people sitting on deckchairs in air raid shelters during the Blitz in London. The researchers, led by Dr Richard Beasley, of the Medical Research Institute of New Zealand, warn that the widespread use of computers in so many aspects of modern life may put many people at risk of developing DVT. The researchers advise anybody who uses a computer for prolonged periods should undertake frequent leg and foot exercises, and take regular breaks away from the screen Patching Up Women's Flagging
Libido (Go To Top) SYDNEY: Move over viagra, this one is better and it's for women. Australia has launched a skin patch that promises to increase the testosterone patches of women who need to rev up their sex lives. The Royal Hospital for Women at Randwick and the Melbourne-based Jean Hailes Foundation are both testing the patches on post- menopausal women as part of a multinational study. The patches, to be worn on the back or buttocks, release the sex hormone testosterone to boost energy and flagging libidos. John Eden, director of the Sydney Menopause Centre at the Royal Hospital, said in an interview with Sydney Morning Herald that he hoped the trial was a step towards greater availability of testosterone products for women. Unlike female or "pink" Viagra - which increases blood flow to the pelvic region - testosterone increased desire and energy, which were the main problems for women with low libido, Dr Eden said. The hospital has already tested a cream, with promising results. But Dr Eden said patches were possibly the easiest way of delivering testosterone into the bloodstream. Injections and skin implants were effective, but painful and invasive. Protein That Causes Cancer
Cells to Commit Suicide Found (Go
To Top) WASHINGTON: A protein that causes cancer cells to self-destroy has been found by US researchers who discovered it destroys up to 70 per cent of cancer cells. It regulates the production of a key enzyme involved in the generation of blood vessels which feed cancer cells' growth. The enzyme is Cox-2, which is already known to play a role in causing arthritis. XXXXXXXX "In the future, it may be possible to use this protein as a means of killing tumour cells without harming normal cells because normal cells already produce significant amounts of the protein," he added. Beat the Genetic Time Bomb
by Postponing Death(Go To Top) LONDON: Help is at hand for people wanting to beat the genetic time bomb. Using the latest genetic science, a home test kit has been devised which can tell you exactly how and when you will die decades before you meet the grim reaper. Pioneered in the US and Britain, scientists say the kit, which costs as little as 500 dollars, will accurately predict what illnesses you are likely to develop and how you will die, simply by looking at your genes. The tests use a sample of DNA obtained by swilling spearmint mouthwash for 60 seconds and spitting the resulting dead cells into a plastic test tube. From this, scientists claim they can determine how likely it is that you will suffer from cancer, heart disease, osteoporosis, arthritis, bowel disease, stomach ulcers, obesity, blood clots or a stroke. They also say that, by taking a blood sample, they can work out if you are likely to become an alcoholic. Within two weeks, the results are delivered to your door, wrapped like a box of chocolates and complete with a list of suggestions - such as a change of diet, taking mineral supplements or doing more exercise. Karen Price, of Health Interlink, which is marketing the tests in Britain, was quoted by the Herald as saying: "They will help people understand how their body works and suggest ways in which people can improve their health and wel-lbeing." A Kiss of Death for Blanket
Octopus (Go To Top) SYDNEY: One of the most baffling cases of gender imbalance has been seen in the case of a blanket octopus. While the male is just two centimetres long, the female of the species can measure up to two metres. And as if being 100 times smaller than his mate wasn't bad enough, he dies right after having sex with her. A senior curator at the Melbourne Museum, Mark Norman, who recently found a living specimen on the Great Barrier Reef, said that until now the male had only been discovered dead in trawls and plankton nets. The male blanket octopus is, technically speaking, the most extreme example of sexual size-dimorphism in a non-microscopic animal, such dimorphism is not seen in any other animal remotely as large. Dr Norman was quoted as saying in the Sydney Morning Herald as saying, "There's no other critters on that scale that have such a significant difference between the male and female." The two-metre female weighs at least 10,000 times as much as the male, sometimes up to 40,000 times as much. This could make the question of position rather delicate, but as it turns out it doesn't matter. The male, it seems, relies on its arm as much as its penis to have sex. This reproductive arm, known as a hectocotylus, is tucked away in a white spherical pouch between its other arms. When males mate, the pouch ruptures, the penis injects sperm into the tip of the arm, the arm is severed, and passed to the female. It stays there until used to fertilise the female's eggs, which can be weeks later. And while the human post-orgasm is sometimes referred to as "the little death", for the male blanket octopus the term takes on literal meaning. The male dies, but the female carries on, free to have sex with more males. Four-winged Dinosaur Fossil
Found (Go To Top) WASHINGTON: A recent find of a set of six fossils of ' four-winged dinosaurs' that lived nearly 130 million years ago, has stunned palaeontologists. Uncovered in China, the fossils could rewrite our understanding of how and why birds first took to the sky. The fossils clearly show a small dinosaur that had flight feathers covering its legs, as well as tail and arms, forming an extra pair of wings never before seen. News of the find comes just days after scientists published work showing that baby partridges flap their tiny wings to help them climb steep slopes, an insight that may explain why wings first evolved. Together, the two discoveries may represent one the most significant advances in the contentious study of avian evolution for decades. Experts have traditionally been split between two mutually exclusive theories. Flight either began with small, fleet predatory dinosaurs leaping from the ground into the air, or with other animals that learnt to fly whilst jumping to earth from trees. But the new studies reveal a far more complex picture, says a report in New Scientist. The Chinese fossils are of a small dinosaur belonging to the Microraptor genus. It is known to be the most primitive dromeosaur, a group of two-legged predatory dinosaurs closely related to birds. Earlier Microraptor fossils did not preserve feathers. But the best of the six new specimens, thought to belong to a new species, have the most extensive coat of feathers ever seen on a dinosaur. The animal was presumably light enough to fly - the best- preserved skeleton is just 77 centimetres from the nose to the tip of the long tail. There is "no doubt the new animal is a flying animal," says Xing Xu from the Institute for Vertebrate Paleontology and Paleoanthropology in Beijing, who describes the new fossils in Nature. Xu describes it as a "four-winged dinosaur". Instead of being capable of powered flight, Xu believes that Microraptor used all four limbs to climb trees, and then glide back down again. But Microraptor gui, as it has been dubbed, is unusual because it has feathers at the ends of its arms and legs that are twice as long as those close to its body. Gene Therapy for Poor Blood
Circulation in Legs (Go To Top) WASHINGTON: Experiments on gene therapy reveal that it successfully stimulates the growth of new blood vessels and its high success rate means it may replace the need for amputation in people with severe circulation problems in their legs. Researchers from the Jobst Vascular Centre in Ohio presented their findings at the 15th Annual International Symposium on Endovascular Therapy in Miami Beach on January 21. They conducted a Phase I trial to assess a genetically engineered angiogenic growth factor called NV1FGF in legs with severely blocked blood vessels, says a report in Health Scout. The study of 51 patients found the treatment was safe and the procedure showed some evidence - less pain, improved ulcer healing and enhanced blood pressure - of improved blood circulation in the legs. Diabetes, smoking, high cholesterol levels and genetics can cause people to develop blocked arteries in the legs. In most of those people, bypass surgery or angioplasty can restore circulation. However, some people with blocked arteries in the legs don't respond to standard treatments and have a poor prognosis. As many as 40 per cent of those people must have leg amputation, and one in five dies within six months, the researchers say. Stem Cells Can Repair Damage
from MS (Go To Top) SYDNEY: A new research conducted in a hospital here has found that damage caused by multiple sclerosis (MS) can be repaired by using stem cells extracted from a patient's bone marrow. In patients suffering from MS, the research said, the immune system attacks myelin causing progressive muscle weakness, memory and vision problems. A team of doctors at St Vincent's Hospital coaxed adult stem cells from mice and people into becoming oligodendrocytes - cells that manufacture the fatty myelin sheath that insulates nerve cells. They then injected the cells into the brains of mice designed to act as models of human MS. It was found that the damaged myelin was replaced. Dr Bruce Brew, who led the team of doctors, said this suggests that patients could conceivably have their deficits partly or wholly reversed. Millions Infected With Deadly
Parasite Spread by Cats(Go To Top) LONDON: Research on diseases spread by pets has come up with alarming results. According to a recent study, the domestic cat has spread a parasite that causes devastating birth defects in humans. More than a quarter of the world's population is now infected with toxoplasma gondii, a relative of the malaria bug, the study conducted by an Anglo-American team and reported in the Telegraph said. Infected people with weakened immunity often develop acute toxoplasmosis, which can lead to birth defects, brain inflammation and vision problems. It has also been suggested that the parasite, which invades the brain, may influence behaviour and trigger schizophrenia. Although it can sexually reproduce only in cats, the creature mutated so it could asexually reproduce in a vast range of warm-blooded hosts, including humans. Dr David Sibley and colleagues at Washington University, St Louis, Cambridge University and the University of Georgia claim that the three main strains of the toxoplasma arise from a single mating about 10,000 years ago. Electric Cables a Viable
Option for Internet Access (Go
To Top) WASHINGTON: Instead of cable and telephone lines, power lines may be soon used for high-speed Internet access, claim experts. Edmond Thomas, chief of the Federal Communications Commission's Office of Engineering and Technology, was quoted by the Wired as saying that the technology offers an alternative to cable and telephone lines as a way to get broadband service, with its ability to quickly deliver large amounts of data and high-quality video signals. "Every power plug in your home becomes a broadband connection," he said, adding that companies developing the technology have overcome many hurdles in the past year. Such an alternative could lead to more competition and lower prices. The FCC has been studying the technology for several months and will pay more attention to it this year, Thomas said. He added that no regulations prohibit the technology, but the agency is concerned that Internet transmissions carried over power lines could emit signals inside and outside the home that could cause interference. Doomsday for Bananas Appears
Close (Go To Top) LONDON: Bad news for banana lovers. Scientists have warned that the world's favourite fruit was at crisis point and could be extinct within ten years. Reason: the fruit is unable to fight off a rampaging plague of pests and disease. Emile Frison, head of a world-wide network of banana researchers, said there has been a decline in yields of bananas in Africa, Asia and Central America, reports the Telegraph. The doomed banana's Achilles heel is that it is a genetically decrepit sterile mutant. One of the oldest crops, the first edible variety was propagated about 10,000 years ago from a rare mutant of the wild banana which, with a mass of hard seeds, is virtually inedible. But because all edible bananas are sterile - effectively clones of that first plant - they are unable to evolve to fight off new diseases. Black sigatoka, a fungal disease that cuts yields by up to three quarters and reduces the productive lives of banana plants from 30 to only two or three years, has become a global epidemic. The fungus reduced yields by 40 per cent in a year in Uganda, the world's second largest producer, and is spreading through the Brazilian Amazon and the Far East. Frison, director of the International Network for the Improvement of Banana and Plantain, said black sigatoka was no longer being kept in check. Luadir Gasparotto, Brazil's leading banana pathologist, said that the production in Brazil, the world's fourth largest producer, was likely to fall by 70 per cent because of sigatoka. To make matters worse, Panama disease, a fungus that wiped out a popular variety in the 1950s, has also returned. Genetic engineering may be the only answer. Last year, scientists led by Frison announced plans to sequence the genetic blueprint of the banana within five years, focussing on inedible wild bananas, many of which are resistant to black sigatoka. But large producers have refused to back the research because of costs and fears that consumers will not accept it. Half a billion people in Africa and Asia depend on bananas for up to half their daily calories. Britain imports more than seven billion bananas a year, making it the nation's favourite fruit. More than 140 million are eaten every week. Idea of a 'Space Sheepdog'
to Clear Debris Out of Skies (Go To
Top) WASHINGTON: Space junk poses an increasingly serious danger to spacecraft. Low-Earth orbits are now littered with about 1900 tonnes of debris. Now, an aerospace company is proposing to deploy what it calls a "space sheepdog" to usher space junk safely out of orbit. Most of the junk is accounted for by a relatively small number of large items such as spent launchers and dead satellites, which are easy to track and avoid. But that could change. In some orbits, a chain reaction is under way: fragments from past collisions are becoming involved in more collisions, generating more fragments, and so on. "It's a very slow process but at some point we will have to tackle this problem," Joe Carroll, an aerospace engineer at Tether Applications, a space technology company based in California, was quoted as saying in New Scientist. One way to clear the skies is to attach rocket motors to the largest objects and send them crashing to Earth. But this requires large amounts of fuel to put the rockets into orbit and power them when they get there. So Carroll suggests a more elegant solution: a reusable solar-powered craft that manoeuvres using forces generated when an electric current interacts with the Earth's magnetic field. NASA's Institute for Advanced Concepts is funding a feasibility study into his idea. The main component of Carroll's vehicle is a conducting wire several tens of kilometres long, known as an electrodynamic tether, carrying an electric current. As the tether sweeps through the Earth's magnetic field, the current interacts with the field, raising or lowering the craft's orbit. "It's a bit like tacking in a sail boat. You push and pull against the field until you get where you want," says Carroll. His plan is to equip the tether with a roving sheepdog, a small vehicle that is released near a piece of debris to fly around it looking for a suitable point to latch onto. Once attached, it returns to the tether with its prize in tow. The tether then heads for another piece of junk and sets the sheepdog loose again. "A single tether could be reused up to 100 times, capturing a piece of junk many times its own mass each time, " he says. Anthrax Toxin Found Able
to Kill Tumours in Mice (Go To Top) LONDON: A version of anthrax toxin has been used by scientists to kill tumours in mice. It turned out to be so effective that after just one treatment, the size of the tumours were reduced by up to 92 per cent without damaging normal tissues. The technique, developed by researchers from the US National Institutes of Health, works by targeting a protein called urokinase, which is produced in high levels by cancerous cells. The researchers genetically altered the structure of the anthrax toxin and so it only invaded cells that produced high levels of urokinase. The toxin effectively killed several types of tumour cells, without causing any apparent damage to normal tissue. Tumour cells began dying just 12 hours after the first treatment. Two treatment cycles were enough to completely obliterate 88 per cent of a type of tumour called a fibrosarcoma. It also knocked out 17 per cent of a second type of tumour called a melanoma. However, the toxin did not damage skin cells or hair follicles surrounding the tumour - suggesting that the toxin is highly selective, and may not lead to the severe side-effects sometimes associated with alternative treatments. The researchers stress that further research is needed to determine if the engineered anthrax toxin will have similar effects in humans. Lead researcher Dr Steve Leppla told BBC, "The fact that our cytotoxin can successfully kill several different solid tumours suggests it may be even better on leukemias, where the toxin has an easier time reaching every tumour cell. We are testing that now". The research has been published in the Proceedings of the National Academy of Sciences. Less Heart Attack Risk for
Frequent Drinkers, Say Researchers (Go
To Top) SYDNEY: A long-term study has revealed that men who drank alcohol moderately three or more days per week had reduced risk of heart attack compared to those who drank less frequently. The 12-year study, published in New England Journal of Medicine, of 38,077 male health professionals looked at the relationship between quantity and frequency and found that it was the frequency of drinking - not the type of alcohol, or whether or not it was consumed with a meal - that was the key factor in lowered heart disease risk. By the end of the 12-year follow-up, the investigators had documented 1,418 heart attacks. Men who consumed alcohol three or more times a week had a reduced risk of fatal or non-fatal heart attack, even when the amount consumed was only 10 grams of alcohol a day or less. A standard drink - a 12-ounce bottle of beer, a 5-ounce glass of wine, or 1.5 ounces of 80-proof distilled spirits - has between 11 and 14 grams of alcohol. However, the researchers said that they do not advise the public to begin drinking alcohol to prevent heart disease. However, those who already drink alcohol should be aware that current evidence suggests that moderate drinking may reduce the risk of heart disease in some individuals. Two Scientists Equate Speed
of Gravity With That of Light (Go
To Top) WASHINGTON: Experiments to calculate the speed of gravity reveal that it travels at the speed of light. This is the first time the speed of gravity has been measured. Ed Fomalont of the National Radio Astronomy Observatory in Charlottesville, Virginia, and Sergei Kopeikin of the University of Missouri in Columbia made the measurement with the help of the planet, Jupiter. "We became the first two people to know the speed of gravity, one of the fundamental constants of nature," the scientists say, in an article in New Scientist. One important consequence of the result is that it places constraints on theories of "brane worlds", which suggest the Universe has more spatial dimensions than the familiar three. Einstein had assumed it travelled at the speed of light and built this into his 1915 general theory of relativity. Light-speed gravity means that if the Sun suddenly disappeared from the centre of the Solar System, the Earth would remain in orbit for about 8.3 minutes - the time it takes light to travel from the Sun to the Earth. Then, suddenly feeling no gravity, Earth would shoot off into space in a straight line. But the assumption of light-speed gravity has come under pressure from brane world theories, which suggest there are extra-spatial dimensions rolled up very small. Gravity could take a short-cut through these extra dimensions and so appear to travel faster than the speed of light - without violating the equations of general relativity. But how can you measure the speed of gravity? One way would be to detect gravitational waves, little ripples in space-time that propagate out from accelerating masses. But no one has yet managed to do this. Kopeikin found another way. He reworked the equations of general relativity to express the gravitational field of a moving body in terms of its mass, velocity and the speed of gravity. If you could measure the gravitational field of Jupiter, while knowing its mass and velocity, you could work out the speed of gravity. The opportunity to do this arose in September 2002, when Jupiter passed in front of a quasar that emits bright radio waves. Fomalont and Kopeikin combined observations from a series of radio telescopes across the Earth to measure the apparent change in the quasar's position as the gravitational field of Jupiter bent the passing radio waves. From that they worked out that gravity does move at the same speed as light. Their actual figure was 0.95 times light speed, but with a large error margin of plus or minus 0.25. Their result, announced on Tuesday at a meeting of the American Astronomical Society meeting in Seattle, should help narrow down the possible number of extra dimensions and their sizes. If Smokers Eat Fish Daily,
Their Arteries Won't Harden (Go To
Top) LONDON: Researchers at the Beaumont Hospital in Dublin have found that consuming a portion of fish daily may help to reduce hardening of arteries in smokers. The condition, known as endothelial dysfunction, means the arteries are not able to dilate as they should, leading to atherosclerosis, the narrowing of the arteries that increases the risk of heart attacks. For the study, published in the Circulation, the researchers who gave supplements of taurine, an amino acid present in oily and white fish, to 30 smokers and non-smokers found it reduced the hardening of the arteries caused by smoking. The researchers tied tourniquets round the arms of smokers and non-smokers and measured the change in blood vessel size by ultrasound, reports Independent.co.uk The findings showed dilation of the blood vessels in non-smokers but not in the smokers. But when the smokers were given a dose of 1.5 grams of taurine a day, the amount found in one serving of fish, the difference between the groups disappeared. Professor David Bouchier-Hayes, who led the research said: "When blood vessels are exposed to cigarette smoke it causes the vessels to behave like a rigid pipe rather than a flexible tube, so the vessels can't dilate in response to increased blood flow. "We are not trying to find a therapeutic treatment for smoking because we believe the best therapy for smokers is to stop smoking. None the less, smokers provide a good clinical model for treatment of endothelial dysfunction." The researchers found that vitamin C had a similar though less pronounced effect on the blood vessels of smokers. 'Stem Cell Injections to Aid
Heart Patients' (Go To Top) LONDON: A new study, conducted at the University of Rostock in Germany, has found that heart attack patients when given injections of cells from their bone marrow showed impressive recoveries. The researchers believe that the cells may help new tissue to grow within the organ, according to a BBC report. According to the researchers, laboratory experiments have shown that if bone marrow cells are injected into damaged heart tissue, it triggers the growth of fresh blood vessels to supply the damaged region. This is because certain cells in the bone marrow are called 'stem cells' - master cells which have the ability to grow into many different types of cell. In the heart tissue, scientists think they are prompted to grow into new tissues, helping the organ compensate for the damage it has suffered, they added. For the study, the German team injected these cells into the hearts of six patients who had suffered attacks. Because the treatment is unproven, these patients were also given conventional procedures, such as heart bypass operations, to help keep their hearts going. The findings revealed that all the patients did well after surgery - and five had unusually good blood flow to the heart, according to the report. Professor Gustav Steinhoff, who led the team was quoted by BBC as saying: "We have shown that local bone marrow stem cell implantation together with a bypass operation is safe. Controlled studies are needed to clarify the role of cell transplantation in myocardial regeneration." Another team from the University of Hong Kong carried out a similar experiment, according to a report in the Lancet. They injected stem cells into eight patients - all of whom had improved heart function three months later. However, some researchers have warned against over-optimism by either doctors or patients and said further research is needed. GM Potatoes to Fight Malnutrition
in Indian Poor (Go To Top) BANGALORE: The Indian Government is introducing an ambitious mid-day meal scheme that includes genetically modified potatoes that will be fed to poor children to redress deficiencies in their diets. The three-pronged attack on childhood mortality would aim to provide children with clean water, better food and vaccines. "Zero child mortality in under-privileged children would be the goal," Govindarajan Padmanaban, a biochemist at the Indian Institute of Science here, was quoted as saying in New Scientist. The scheme is formulated in collaboration with charities, scientists, Government institutes and the industry. Local activists had opposed the recent licensing of Bt cotton - which carries a gene for a bacterial pesticide - on the ground it is "unnatural", and that it could kill beneficial insects. Combination Hormone Therapy
Linked to Rise in Breast Density (Go
To Top) WASHINGTON: A new study has suggested that the use of combination hormone therapy, but not estrogen alone, is associated with a modest increase in breast density, a known risk factor for breast cancer. The degree of breast cancer risk that is associated with breast density is greater than that associated with almost all other known breast cancer risk factors. A previous analysis of data from the Post-menopausal Estrogen/Progestin Interventions (PEPI) Trial showed that some women who used combination estrogen/progestin therapy experienced an increase in breast density. However, the analysis did not look at the magnitude of that increase. Past studies have suggested that the greater the breast density, the greater the risk for breast cancer. Gail A Greendale, of the University of California Los Angeles School of Medicine, and her colleagues examined digitized mammograms at baseline and after one year of therapy from 571 post-menopausal women enrolled in the PEPI trial. They found that use of estrogen/progestin combination therapy was associated with five per cent increases in breast density. Use of estrogen alone was not associated with such increases in breast density. |
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