Suspended Animation
Scientists looking at inducing artificial hibernation to buy valuable time for critically ill and injured patients
Link confirmed between Agent Orange and diabetes
WASHINGTON
Agent Orange, the chemical defoliant widely used during the Vietnam War by US forces, is associated with diabetes found in American veterans, a Pentagon study said. "Results from the 2002 physical examination support adult-onset diabetes as the most important health problem seen in the Air Force Health Study" among veterans examined, the Pentagon said.
Agent Orange contains the highly toxic agent dioxin.
The results "suggest that as dioxin levels increase, not only are the presence and severity of adult-onset diabetes increased, but the time to onset of the disease is decreased."
"A 166-percent increase in diabetes requiring insulin control was seen in those with the highest levels of dioxin," a finding consistent with animal studies, the Pentagon said.
The results were gathered from a 2002 medical examination of 1,951 Vietnam veterans, an extension of an ongoing epidemiology study begun in 1982. They confirm reports dating from 1992 and 1997. Veterans examined were among those who had sprayed herbicides in Vietnam between 1962 and 1971 to destroy vegetation and deny the North Vietnamese Army cover and access to crops. The Americans were exposed to the toxic agent during missions or when carrying out maintenance work on aircraft.
A US medical report also established a link between exposure to Agent Orange and chronic lymphoid leukemia.
Australian fitted with new-generation bionic arm
SYDNEY
An Australian has become the first person in the world to be fitted with a new-generation German-made bionic arm capable of lifting six times as much as earlier versions.
Train driver Peter Eberle lost his arm when it was crushed between two carriages 10 years ago and was originally told he could never wear a prosthetic limb because his amputation was too high up the arm. Eberle proved the doctors wrong and eventually mastered the use of a cable-operated bionic arm. But he said it was heavy and left his shoulder aching at the end of the day.
The new version called the Dynamic Arm has a motor built into the artificial hand to increase dexterity. It costs US$50,000, is 25-percent lighter, three times as fast, and can lift significantly more weight.
"It's getting closer to performing like his old flesh and blood does," said prosthesist David Wilson-Brown of Caulfied General Medical Hospital. He said that as the residual muscle in Eberle's stump contracted it produced a small amount of energy, which sensors in the prosthesis detected and translated into commands.
"It piggybacks off the muscles they have and the response is almost instantaneous," he said. "The patient has total control over the speed of the elbow and the speed and grip force of the electric hand."
On-demand hibernation
WASHINGTON
US scientists have for the first time eased mice in and out of hibernation, a possible procedure for treating critically ill and injured humans. Scientists at the Fred Hutchinson Cancer Research Center in Seattle, Washington, exposed the mice to high levels of hydrogen sulfide to put them into hibernation, suspending most metabolic activity, Science magazine reported. Later the mice were revived showing no significant ill effects.
"We are, in essence, temporarily converting mice from warm-blooded to cold-blooded creatures, which is exactly the same thing that happens naturally when mammals hibernate," said lead investigator Mark Roth. "We think this may be a latent ability that all mammals have--potentially even humans--and we're just harnessing it and turning it on and off, inducing a state of hibernation on demand."
In a hibernation-like state, cellular activity almost stops completely, reducing the organism's need for oxygen. Applied to humans, this could gain valuable time for critically ill patients in operating rooms, injured soldiers on battlefields, and those awaiting organ transplants, according to Roth. It could help people suffering from severe fever, as well as those undergoing cancer treatment by protecting normal cells during radiation and chemotherapy.
For the mice, the artificial hibernation was induced using hydrogen sulfide, a chemical normally produced in humans and animals that scientists believe helps regulate body temperature and metabolic activity. The mice's respiration and temperatures plunged drastically as they appeared to lose consciousness, the study noted. They were then revived with little apparent effect.
Roth and his colleagues said the technique could possibly be used within five years to help people suffering severe fevers of unknown origin. "Here's a patient group…who would do well if they could just have their core body temperature taken down in order to buy them time until the pathology reports come back and they can get on the right course of treatment," Roth said.
Pomegranate reduces risk of brain injuries in babies
CHICAGO
Drinking pomegranate juice during pregnancy may help reduce the risk of brain injuries in babies, US researchers have found.
Decreased blood flow and oxygen to an infant's developing brain during pregnancy is linked to premature birth and can lead to brain- tissue loss, seizures, and mobility impairments such as cerebral palsy. It may also happen during birth and in the early days after. The phenomenon called hypoxic ischemia causes brain injury in two of every 1,000 full-term births and in a very high percentage of babies born before 34 weeks of gestation.
But researchers at the Washington University School of Medicine in St. Louis found that newborn mice whose mothers drank water mixed with pomegranate concentrate lost 60-percent less brain tissue than mice whose mothers drank sugar water or other fluids.
"Hypoxic ischemic brain injury in newborns is very difficult to treat, and right now there's very little we can do to stop or reverse its consequences," senior researcher David Holtzman, who heads the university's Department of Neurology, said. "Most of our efforts focus on stopping it when it happens, but if we could treat everyone who's at risk preventively, we may be able to reduce the impacts of these kinds of injuries."
Pomegranates contain very high concentrations of polyphenols, a substance also found in berries and grapes, which has been shown to potentially have antiageing and neuroprotective effects.
The study, which appears in Pediatric Research, was conducted in collaboration with a US producer of pomegranates.
"Drugs-from-the-sea" breakthrough
SYDNEY
A team of international scientists has successfully cloned marine DNA in a breakthrough they say will provide promising "drugs from the sea" to treat cancer and viral diseases.
The team, working at the Australian Institute of Marine Science (AIMS), said that the cloning of DNA from marine organisms like sponges, and sea squirts into E. coli could provide a sustainable supply of marine-derived medicines.
Walt Dunlap, a leading biochemist at AIMS, said compounds from sea squirts, sponges, and other marine organisms showed exceptional promise for the treatment of cancer, inflammation, and viral diseases. "The main problem has been obtaining a large-scale supply of these complex chemicals for worldwide use in an ecologically sustainable and economically viable way," he said.
The new methodology developed by a team of scientists from AIMS, the University of Aberdeen, and the London School of Pharmacy has removed "a huge hurdle to the development of new drugs from the sea," he said. "Using gene technology we need not return to the sea again to obtain the drug for worldwide use."
Despite their potential in curing disease, few marine-derived drugs reach the market because of the considerable cost of developing a guaranteed supply for clinical use.
"Without an assured source pharmaceutical companies are unwilling to invest the estimated US$600 million it takes to get a drug from the sea to the shelves," said Chris Battershill, lead AIMS scientist on the project. "To produce a cancer-fighting drug from a marine source, for example, we might need to harvest 20,000 tons of a particular sponge per year to meet the global market need and this is ecologically unsound."
The AIMS team solved the problem by taking the genes responsible for manufacturing a cancer-fighting chemical produced by a sea squirt and placing them in E. coli.
"Using this methodology, we need only one small collection of the sea squirt to obtain a long-term supply of the chemical, which has potential for the treatment of certain types of lymphoma," said Paul Long, a team member from the London School of Pharmacy.
The research was published in ChemBioChem.
Vitamin C not a "magic bullet" v. common cold
SYDNEY
Taking extra vitamin C does little to stop most people from catching a cold, according to a new survey, but it helps stop those exposed to extreme physical conditions from coming down with the sniffles.
Soldiers and skiers are among those most likely to benefit from taking extra doses of the vitamin and marathon runners are clear winners, said Prof. Bob Douglas of the Australian National University. "The marathon runners are the most impressive and I don't think we can assume it necessarily protects to the same extent people who are engaged in moderate physical activity and cold stress," he said. "But we can be quite confident that for ordinary people it doesn't make much difference. It doesn't lessen their risk; they might have a very slight reduction in the length of their cold-- about half a day or a day."
The study into the impact of vitamin C in preventing colds and flu, conducted in collaboration with associate professor Harri Hemila of Finland's University of Helsinki, surveyed 55 other studies carried out over the past 65 years and is the most extensive of its kind.
Almost half of the previous studies show that taking a daily dose of at least 200 milligrams of vitamin C makes no difference to the incidence of the common cold. But in a subgroup included in six studies, which focused on people exposed to cold and physical stress, vitamin C reduced the illness by half.
Some 30 studies noted that eight percent of adults and 13 percent of children who continued to take vitamin C while they had a cold cut short its duration. And one study found that if a high dose (eight grams) was taken at the onset of symptoms the length of the illness was cut short.
But overall, Douglas said the findings, published in US-based online medical journal PLoS Medicine, did not justify regular use of vitamin C as a preventive agent. Vitamin C had not proved to be a "magic bullet" to solve the common cold, he said.
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