Universal flu vaccine in the making

Researchers are developing an influenza vaccine that protects against different strains of the flu, including potential pandemic viruses.

While drug companies currently manufacture different flu vaccines each year to match the strains of influenza that researchers predict to circulate, a universal influenza vaccine could improve protection against strains of the virus as they change.

According to Robert Belshe, who is leading the research at the Saint Louis University, scientists have taken a 'significant first step' in creating the universal vaccine.

Belshe and his colleagues studied a vaccine made with proteins from two of the five main strains of inflenza: influenza viruses A and B.

377 healthy adults received three injections of the vaccine, known as Bivalent Influenza Peptide Conjugate Vaccine (BIPCV), over a six month period.

Researchers found that a low dose of the vaccine is well tolerated and safe. The low dose vaccine also evoked an immune response, high antibody titers, that is similar to levels associated with protecting small animals infected with influenza from serious disease and death.

“This is a significant first step in developing a universal vaccine to help protect against pandemic influenza,” Belshe said, noting that more testing is needed.

More information is available from the Saint Louis University Medical Center's press release.

READ MORE »

Plastic containers could contaminate drinking water

Potent, man-made hormones could be leaching out of plastic water bottles into bottled drinking water, German researchers have found.

In an analysis of 20 brands of mineral water available in Germany, researchers from the Goethe University detected estrogen contamination in 60 percent of the samples.

Estrogen functions as the primary female sex hormone. In humans, it promotes the formation of breasts and is used in some oral contraceptives.

The researchers tested the extent and effect of estrogen contamination by breeding New Zealand mud snails in both plastic and glass water bottles.

Mud snails in plastic bottles were found to produce more than double the number of embryos of those in glass bottles.

Specifically, one third of the glass bottled samples showed what researchers called 'significant hormonal activity', compared with nearly 80 percent of water in plastic bottles.

More information is available from Martin Wagner and Jörg Oehlmann's online journal article.

READ MORE »

Older men may father less intelligent kids

Children of older fathers perform less well in a range of cognitive tests during infancy and early childhood, a recent study has found.

Queensland Brain Institute researcher John McGrath analysed data about 33,437 children who were born between 1959 and 1965 in the United States.

Children were subject to cognitive testing at 8 months, 4 years and 7 years of age to measure the ability to think and reason, including concentration, learning, memory, speaking and reading skills.

The study found that the older the father, the more likely the child was to have lower scores on the various tests -– with the exception of one measure of physical coordination.

In contrast, the study found that children with older mothers gained higher scores in the same tests.

While previous researchers have suggested that older mothers may provide a more nurturing home environment, the Queensland Brain Institute study suggests that children of older fathers do not necessarily experience the same benefit.

McGrath and his colleagues hypothesise that the link between paternal age and a child's cognitive ability could be due to inferior sperm.

Unlike a woman's eggs, which are formed when she herself is in the womb, a man's sperm accumulates over his lifetime, which previous studies have suggested can mean increased incidence of mutations in the sperm at an older age.

More information is available from the research paper, which was published this week in PLoS Medicine.

READ MORE »

Young people may risk over-caffeination

The growing popularity of energy drinks among 18- to 24-year-olds could have a negative impact on the young people's health, researchers warn.

According to Stéphanie Côté, a nutritionist at the Université de Montréal in Canada, energy drinks are 'the coffee of a new generation', used to fuel late night study sessions, all-night parties, and physical activity.

A 2008 report by Agriculture and Agri-Food Canada estimates 1.5 billion cans of the Red Bull energy drink to have been sold in the United States in 2004. Consumption is said to be a growing trend for 18- to 24-year-olds, and younger children also are beginning to consume caffeine-rich drinks before doing physical activity.

But energy drinks are not recommended to either athletes or children under the age of twelve. Furthermore, researchers warn that the strong doses of caffeine found in these drinks can increase hypertension, cause heart palpitations, provoke irritability and anxiety as well as cause headaches and insomnia.

"These [energy] drinks are made up of sugar and caffeine and can have a negative impact on health," Côté said. "Energy drinks don't hydrate the body efficiently because they have too much sugar, and caffeine doesn't necessarily improve physical performance."

"In high quantities it [caffeine] can increase the risks of fatigue and dehydration," she said, noting that Health Canada does not recommend consuming more than two cans of energy drinks per day.

More information is available from the Université de Montréal's press release (in French).

READ MORE »

Viagra helps hamsters overcome jet lag

A hamster-size dose of sildenafil, more commonly known by its marketing name Viagra, helps the rodent recover more quickly from a six-hour advance in its daily cycle, researchers report.

Originally developed for the treatment of high blood pressure and angina, Sildenafil works by interfering with an enzyme that reduces levels of a naturally-occurring compound, cyclic guanine monophosphate (cGMP). In the brain, cGMP has an important function in a signalling pathway that regulates the body’s daily clock.

Biotechnologist Patricia Agostino and colleagues at the Universidad Nacional de Quilmes in Argentina injected hamsters with sildenafil at night, before turning on bright lights six hours earlier than natural sunrise. The team then observed how the hamsters adjusted to the change, by noting how soon they began running in their exercise wheels.

Sildenafil-boosted hamsters recovered from the jet lag up to 50 percent more quickly than unassisted animals. However, the drug only worked when applied before an advance in the light/dark cycle, equivalent to an eastbound flight, rather than the reverse.

The scientists believe that frequent flyers and shift workers could benefit from moderate doses of sildenafil.

The study will be published in the U.S. journal, PNAS, this week.

READ MORE »

Alcohol: friend or foe?

It is no secret that Australians like to keep in high spirits. Of course, beer and wine are popular too.

Recently released statistics on drug use found the average Australian to have consumed 92 litres of beer, 20 litres of wine, and 1 litre of pure alcohol from spirits in 2004 alone. About 35 percent of drinkers were found to consume ‘risky’ levels of alcohol, the abuse of which has been blamed for more than a quarter of all deaths of 15 to 29 year-olds in developed countries.

According to biotechnologists from the University of Granada in Spain, however, melatonin found in red wine could delay the oxidative damage and inflammatory processes typical of old age. Though laboratory tests with mice, scientists speculate that daily melatonin intake in humans from the age of 30 or 40 could delay illnesses related to aging, thus promoting longevity.

While exploring ways to keep berries fresh during storage, researchers at the Kasetsart University in Thailand have discovered health benefits in treating the fruit with alcohol. Besides helping berries resist decay, alcohol was found to increase antioxidant capacity within strawberries, and could also increasing their ability to prevent diseases ranging from cancer to neurodegenerative disorders.

Strawberry daiquiri, anyone?

READ MORE »

Chill out, live longer

A psychological study has linked neuroticism and mortality, suggesting that mellowing with age could help people live longer.

In the study, researchers tracked the change in neuroticism levels of 1,663 aging men over a 12-year period.

A neurotic personality was defined as a person with the tendency to worry, feel excessive amounts of anxiety or depression and to react to stressful life events more negatively than people with low levels of the trait. Neuroticism levels were measured using a standardized personality test.

Using the data gathered in the first analysis, researchers calculated the men's mortality risk over an 18-year period using the average levels and rates of change.

By the end of the study, half of those men classified as highly neurotic with increasing levels of neuroticism had died while those whose levels decreased or were classified as less neurotic had between a 75 percent and 85 percent survival rate.

"We found that neurotic men whose levels dropped over time had a better chance at living longer," said Dan Mroczek, an associate professor of child development and family studies at Purdue University, who conducted the study. "They seemed to recover from any damage high levels of the trait may have caused. On the flip side, neurotic men whose neuroticism increased over time died much sooner than their peers."

The study will be published in the print edition of the U.S. journal Psychological Science in late May. More information is available from Purdue University’s press release.

READ MORE »

Cannabis could provide relief to stroke patients

Some mechanisms in the brain targeted by cannabis have been found to have potentials in countering brain cell damage after a stroke.

New research by scientists at the University of Otago in New Zealand has shown that the cannabinoid CB2 receptor appears in the rat brain following a stroke. The findings have been touted as a world-first, and were published recently in the international journal Neuroscience Letters.

The CB2 receptor is a protein produced in response to stroke as part of the body's immune response system. This response causes the inflammation that leads to damage in the area of the brain around where the stroke has occurred, according to John Ashton, a medical researcher at the University’s Department of Pharmacology and Toxicology.

"If the inflammation can be stopped or reduced then it offers the hope of reducing the extent of the damage caused by stroke - and CB2 offers a potential target for such a drug,” he said.

Ashton explained that the active ingredient of cannabis, THC, targets both the CB2 and the related CB1 receptors. But while THC has been known to have some positive effects for pain management, its use is currently severely limited because of how it triggers the psychoactive CB1 receptors in the brain.

"The aim would be to develop a drug that targets the CB2 receptor without affecting CB1," Ashton said, suggesting a pharmaceutical approach similar to that that has already been taken to develop codeine from heroin.

"Heroin and codeine share common targets, but by designing codeine in such a way that it eliminated the psychoactive side-effects seen with heroin, a therapeutically useful drug was developed. There is the potential to do the same with cannabinoids," he said.

Drugs targeting CB2 could also have potential therapeutic use in other conditions involving inflammatory damage to the brain, such as Huntington's Disease and Alzheimer's Disease. There may also be scope to use them in pain management.

More information is available from the University of Otago’s press release.

READ MORE »

Brain’s breaking mechanism revealed

As wise as the counsel to ‘finish what you've started’ may be, it is also sometimes critically important to do just the opposite - stop. And according to a recent cognitive study, the ability to stop quickly, to either keep from gunning the gas when a pedestrian steps into your path or to bite your tongue mid-sentence when the subject of gossip suddenly comes into view, may depend on a few ‘cables’ in the brain.

Researchers led by cognitive neuroscientist Adam Aron, an assistant professor of psychology at the University of California, San Diego, have found white matter tracts - bundles of neurons, or 'cables', forming direct, high-speed connections, between distant regions of the brain - that appear to play a significant role in the rapid control of behaviour.

The study is the first to identify these white matter tracts in humans, confirming similar findings in monkeys, and the first to relate them to the brain's activity while people voluntarily control their movements.

"Our results provide important information about the correspondence between the anatomy and the activity of control circuits in the brain," Aron said. "We've known for some time about key brain areas involved in controlling behaviour and now we're learning how they're connected and how it is that the information can get from one place to the other really fast."

"The findings could be useful not only for understanding movement control," Aron said, "but also 'self-control' and how control functions are affected in a range of neuropsychiatric conditions such as addiction, Tourette's syndrome, stuttering and Attention Deficit Hyperactivity Disorder."

To reveal the network, Aron and a team of researchers from UCLA, Oxford University and the University of Arizona performed two types of neuroimaging scans on healthy volunteers.

They used diffusion-weighted MRI, in 10 subjects, to demonstrate the "cables" between distant regions of the brain known to be important for control, and they used functional MRI, in 15 other subjects, to show that these same regions were activated when participants stopped their responses on a simple computerized "go-stop" task.

Renderings of the brain’s "braking" network, viewed from the front and side. A cutaway of the right hemisphere reveals white matter tracts, or "cables," that connect three distant regions of the brain known to be important for controlling behaviour - David Flitney, Oxford University
One of the connected regions was the subthalamic nucleus, within the deep-seated midbrain, which is an interface with the motor system and can be considered a ‘stop button’ or the brake itself. A second region was in the right inferior frontal cortex, a region near the temple, where the control signal to put on the brakes probably comes from.

"This begs the profound question," Aron said, "of where and how the decision to execute control arises."

While this remains a mystery, Aron noted that an additional, intriguing finding of the study was that the third connected node in the network was the presupplementary motor area, which is at the top of the head, near the front. Prior research has implicated this area in sequencing and imagining movements, as well as monitoring for changes in the environment that might conflict with intended actions.

The braking network for movements may also be important for the control of our thoughts and emotions.

There is some evidence for this, Aron said, in the example of Parkinson's patients. In the advanced stages of disease, people can be completely frozen in their movements, because, it seems, their subthalamic nucleus, or stop button, is always ‘on’. While electrode treatment of the area unfreezes the patients' motor system, it can also have the curious effect of disinhibiting them in other ways. In one case, an upstanding family man became manic and hypersexual, and suddenly began stealing money from his wife to pay for prostitutes.

Examples like these motivate Aron to investigate the generality of the braking mechanism.

"The study gives us new targets for studying how the brain relates to behavior, personality and genetics," Aron said. "Variability in the density and thickness of the 'cable' connections is probably influenced by genes, and it would be intriguing if these differences explained people's differing abilities not only to control the swing of a bat but also to control their temper."

More information is available from the University of California’s press release.

READ MORE »

Male circumcision to control HIV infection

The World Health Organization (WHO) and the joint United Nations Program on HIV/AIDS, UNAIDS, have recommended that male circumcision be added to approved interventions to reduce the risk of heterosexually acquired HIV infection in men.

The recommendation follows what was found to be compelling evidence of the benefits of male circumcision, as presented by three trials carried out on African men between the ages of 18 and 24.

One study was held in Kisumu, Kenya where an estimated 26 percent of uncircumcised men are HIV infected by age 25. The majority of the 2,784 HIV negative, uncircumcised men who participated in the study were Luo, an ethnic group that does not traditionally practice circumcision.

Half the men were randomly assigned to circumcision and half the men remained uncircumcised for two years. Participants received free HIV testing and counselling, medical care, tests and treatment for sexually transmitted infections, condoms and behavioural risk counselling during periodic assessments throughout the study.

The clinical trial, which was led by Robert Bailey, a professor of epidemiology at the University of Illinois, found that 47 of the 1,391 uncircumcised men contracted HIV, compared to 22 of the 1,393 circumcised men.

"Our study shows that circumcised men had 53 percent fewer HIV infections than uncircumcised men," said Bailey. "We now have very concrete evidence that a relatively simple surgical procedure can have a very large impact on HIV."

Two other trials, held in Uganda and South Africa, yielded similar results, indicating that circumcision effectively reduced the rate of new HIV infections by 48 to 60 percent.

But experts warn that countries should consider male circumcision as part of a wider HIV prevention package, including HIV testing and counselling services to prevent men developing a false sense of security.

Circumcised men may feel they are protected from becoming HIV infected, Bailey said, and may be more likely to engage in risky behaviour. However, he said, ‘circumcision is by no means a natural condom’, concluding that circumcision will be most effective if it is integrated with other prevention and reproductive health services.

Kenya's director of Medical Services, James Nyikal, cautiously welcomed the recommendation from the WHO and UNAIDS.

"Although male circumcision considerably reduces the risk of HIV/AIDS transmission, there is a high risk of circumcised men becoming complacent and engaging in risky sexual behaviour," he said.

But while Kevin De Cock, director of HIV/AIDS at the WHO, acknowledges that it will be a number of years before the impact of the research is evident on the HIV epidemic, he said that the joint recommendations of the WHO and UNAIDS represent ‘a significant step forward in HIV prevention’.

"Countries with high rates of heterosexual HIV infection and low rates of male circumcision now have an additional intervention which can reduce the risk of HIV infection in heterosexual men," he said.

More information is available from the University of Illinois’ press release and from SciDev.net’s article announcing the WHO/UNAIDS recommendation.

READ MORE »

Genetically modified pigs could yield organs for human bodies

By Liz Tay
Recent medical advances may shine new hope on the otherwise dismal shortage of human organ donors, by allowing the organs of animals to be transplanted into human bodies instead. It may be awhile yet before the technology, known as xenotransplantation, reaches medical clinics; but when that happens, accusing someone of being pigheaded may take on a new meaning altogether.

Xenotransplantation has been studied and attempted for over a century, but few operations have been successful to date. According to Muhammad Mohiuddin, who studies xenotransplantation at the U.S. National Heart, Lung, and Blood Institute (NHLBI), the major stumbling block of existing techniques is that the immune system in the animal receiving the organ tends to reject the transplant.

"We are still learning about new immunological hurdles and have to overcome these barriers in non-human transplant models," Mohiuddin said.

To study these immunological issues, scientists have studied xenotransplantation across several animal combinations, including the insertion of hamster organs into rats, and later into mice, as well as the transplantation of organs from pigs to baboons.

In a recent paper published in the esteemed journal PLoS Medicine, Mohiuddin cites a study in which insulin-producing cells, called islets, from pigs were transplanted into monkeys with diabetes. This led to the complete reversal of diabetes for over 100 days, researchers said.

However, suppressing immunological issues in the pig-to-monkey studies involved giving the monkeys drugs called immunosuppressants in doses that would be too large to be administered in humans. To overcome the need for overly large amounts of immunosuppressants, Mohiuddin suggests organs be farmed from pigs that are genetically modified to be more compatible with humans.

"Taking out some molecules which are immunogenic to humans and putting in human molecules [in the pig] will make the pig organ more compatible to humans," he said. "This allows us to use safer immunosuppression methods, which are now routinely used in allotransplantation [organ transplantation from human to human]."

Pigs were chosen as potential donors for their organ size, which is said to be comparable to human organs, their short breeding cycle and large litter size, and our ability to genetically manipulate their immune system, Mohiuddin explained.

While there are still some hurdles between current research and the potential use of pigs in human organ donation, such as the objections of animal rights proponents and concerns to do with the transmission of viruses across species, Mohiuddin believes there is a strong case for further research into xenotransplantation.

"In [the] United States alone there are more than 90,000 patients waiting for organ transplantation and only 25,000 transplants were performed during last year," he said. "Most of these patients will die waiting for the organs."

"Xenotransplantation has the potential to save many lives," he said.

READ MORE »

Prepare your body clock for daylight savings

The end of daylight savings time may come with an extra hour on Australian clocks this Sunday, but it won’t necessarily mean more sleep, researchers say.

In fact, according to sleep researcher Sarah Blunden, most people will probably wake up at our body’s usual time, regardless of what the clock says.

“When we set our clocks forward or backward for daylight saving, we also have to re-set our body clocks,” said Blunden, of the University of South Australia’s Centre for Sleep Research. “It’s important to realize that we can’t change our body clock as fast as the clock on the wall.”

To assist in recalibrating one’s body clock, Blunden suggests some exposure to sunlight in the mornings. Light suppresses the sleep-regulating hormone, melatonin, she explained, and the more this melatonin is suppressed in the morning, the more readily it will rise when it is needed in the evening.

Children are expected to find it especially difficult to re-set their body clocks. Blunden said it can take up to a week to get children back on track, and recommends that parents adjust their children’s sleeping and waking schedules gradually, at about 10 to 15 minutes each day.

“This gradual adjustment works really well for most kids and is much better than forcing a child who isn’t sleepy to go to sleep just because the clock says they should," she said.

Parents should also encourage their children to engage in physical activity to burn any excess energy, while being mindful of their exposure to sunlight with minimal exposure in the evenings and maximum exposure in the mornings, Blunden said.

More information is available from the University of South Australia’s press release.

READ MORE »

Mouth-to-mouth resuscitation could do more harm than good

Skip mouth-to-mouth in emergency first aid; a new study has found that patients are twice as likely to survive a heart attack outside a hospital setting if bystanders perform chest-compression-only resuscitation instead of traditional CPR (cardiopulmonary resuscitation) with mouth-to-mouth breathing.

The study analysed the outcomes of 4,068 cases of resuscitation attempts performed by laypeople on adults who had collapsed from cardiac arrest. The observational study was based in the Kanto area in Japan, and is said to be is the first large-scale account comparing the survival rates of out-of-hospital cardiac arrest patients who were treated either with or without mouth-to-mouth ventilations by bystanders at the scene.

According to the study, which was led by Gordon A Ewy, director of the University of Arizona's Sarver Heart Center, mouth-to-mouth breathing takes too much time away from chest compressions, which have to be continuous to improve the chance of survival.

"We have found that the survival rate is higher even when the blood has less oxygen content, but is moved through the body by continuous chest compressions, than when the blood contains a lot of oxygen but is not circulated well because chest compressions are interrupted for mouth-to-mouth ventilations," Ewy said.

Poolside instructions for performing CPR -Flickr.comEwy notes that eliminating the need for mouth-to-mouth ventilation not only is more effective, but also should dramatically increase the incidence of bystander-initiated resuscitation efforts, as studies have found that a majority of people currently are deterred from performing mouth-to-mouth on a stranger, partly out of fear of contracting diseases.

The study was published on March 17 in The Lancet. More information is available from the University of Arizona's press release.

READ MORE »