Clipmarks | pokkets's Biology collection

Scientists find malaria's 'sticky' genes

Wed, 09 Jul 2008 05:45:05 GMT

clipped by: pokkets
clipper's remarks: The understanding of the malaria parasite, which seems to behave in a similar way to a virus, can help the development of new treatment methods, both in the stage that causes the disease in humans, and the phase in which it is carried by the intermediate host, the Anopheles mosquito. Research is also continuing into the genes behind the immune system of the mosquito, which actively fights against the malaria parasite.

Clip Source: www.abc.net.au

Stephen Pincock

Australian scientists have identified a potential new way of combating the global scourge of malaria, by pinpointing eight genes that help the disease-causing parasite remodel our red blood cells.

Malaria kills up to three million people every year, mostly in tropical parts of the world. The disease is spread by mosquitoes that inject victims with microscopic parasites that infect healthy red blood cells

parasites cause radical changes to the structure of the blood cells, hijacking them to produce scores of offspring that go on to infect other cells

"It's like remodeling a house so you can live in it and raise a family," said researcher Professor Alan Cowman from the Walter and Eliza Hall Institute of Medical Research

His group's research will be published this week in the journal Cell.

When the team disrupted just one of the genes, they showed that the infected cells no longer stuck to the walls of blood vessels

"It really is a big step in understanding the parasite itself,"

Microbicides could lead to tougher HIV

Tue, 08 Jul 2008 12:57:53 GMT

clipped by: pokkets
clipper's remarks: An estimated 33 million people have HIV. 66% in Africa. More than 61% of Africans with HIV are women who have been infected by their partners.
They have found tougher HIV is not as likely to be transmitted. Microbicides work with consistent application, and in conjunction with anti HIV medication, which may not be taken.
Reminds me of how Penicillin was once considered to be the the cure for many known diseases. It wasn't long before bacteria developed that were resistant, and the next generation of antibiotics needed to be developed. Now we have the top of the line Methycillin, and MRSA-Methycyllin resistant Staphylococcus Aureas -Golden Staph, and we're reaching the end of this line.. We tried to beat nature, and nature caught us and beat us back. As penicillin was a natural by product of a microorganism, it stands to reason that as many other species have natural antibiotics and defense mechanisms, we can find the next generation of antibiotics by following natures lead.

Clip Source: www.abc.net.au

Maggie Fox

A new mathematical model shows that microbicide gels currently being developed to prevent HIV infection in women could lead to enhanced HIV drug resistance, and paradoxically offer more protection to men.

David Wilson of the University of New South Wales and colleagues developed a virtual clinical trial to explore the effects of new treatments under development and determine what parameters might lead to drug resistance.

researchers present their findings in the latest issue of the Proceedings of the National Academy of Sciences.

Several phase III clinical trials are underway to test the efficacy of various microbicides, targeted for release in five to ten years.

Blower says drug-resistant HIV is less likely to be transmitted from one person to another, therefore male sex partners of such women might be protected from the virus.

What we found out that was interesting or surprising or paradoxical, was that under some conditions males would actually benefit a lot more than females

Older men told to 'use it or lose it'

Tue, 08 Jul 2008 12:31:23 GMT

clipped by: pokkets
clipper's remarks: Other factors that contribute to erectile dysfunction that were taken into account include include age diabetes, and heart disease. Blood is retained by a muscle that stops blood from being returned to the body during arousal. Perhaps without regular exercise it is more inclined to lose its grip on the blood vessels.
How being caught by surprise affected function, was not mentioned

Clip Source: www.abc.net.au

There's new advice for older men who want to preserve their sexual function: have sex, and have it often,

The study, published in the American Journal of Medicine, followed nearly 1000 older Finnish men for five years, and reports that those who were regularly having sex at the start of the study were at lower risk of developing erectile dysfunction (ED)

Dr Juha Koskimaki and colleagues at the University of Tampere in Finland studied 989 men who were between the ages of 55 and 75

8% of men who had reported having sexual intercourse less than once per week had ED

3.2% of men who had intercourse once per week

ED among men

having sexual intercourse three or more times per week was 1.6%.

ED occurs when there are problems with blood flow to the penis. Regular sexual activity

may help maintain healthy blood vessel function in the erectile tissue.

A number of factors contribute to ED development

after taking account of those factors, sexual activity itself remained linked to ED risk

Aboriginal tattoos reflect art, culture

Tue, 08 Jul 2008 00:57:08 GMT

clipped by: pokkets
clipper's remarks: The study and comparison between different art forms, has helped find clues as to the social nature of particular tribes, such as whether they were hunter-gatherers or horticulturalists, and degrees to which tribes interacted, and traded.

Clip Source: www.abc.net.au

Jennifer Viegas

Indigenous Australian body art, such as tattoos and intentional scarring may help to unravel mysteries about where certain groups traveled in the past, what their values and rituals were, and how they related to other cultures

The study by Liam Brady of Monash University's Centre for Australian Indigenous Studies appears in the current issue of the journal Antiquity.

"Distinctive design conventions can be considered markers of social interaction so, in a way (they are) a cultural signature of sorts that archaeologists can use to understand ways people were interacting in the past," says Brady.

Brady documented rock art drawings, including images found on early turtle shell, stone and wood objects, and images that were etched onto the human body through a process called scarification.

body art, rock art, wooden objects and other tangible items have a relatively short shelf life, Haddon's collections and data represent some of the earliest confirmed findings for the region

'Devil-proof' fences to save Tassie icon

Mon, 07 Jul 2008 13:17:46 GMT

clipped by: pokkets
clipper's remarks: The cancer affecting Tasmanian devils is infectious. In areas where the disease is present, up to 95% of the population of devils have been killed.
According to the Save the Tasmanian Devil program the disease is now present across more than 60% of Tasmania.

Clip Source: www.abc.net.au

Dani Cooper

The Tasmanian devil could be living in fenced off areas of Tasmania and mainland Australia in a bid to halt the spread of a deadly cancer currently decimating its numbers.

proposals

came out of a four-day international workshop aimed at looking at ways of saving the world's largest carnivorous marsupial from extinction

Dr Rebecca Spindler, of the Taronga Conservation Society Australia, the sponsors of the Hobart workshop, says intensive management is needed to secure disease-free populations

Recommendations include: captive breeding programs in zoos; translocating the dog-sized mammal to free-range enclosures in the wild on mainland Australia; and erecting secure fencing around disease-free populations in the west of Tasmania

The Tasmanian devil is being affected by a cancer known as the devil facial tumour disease. It causes large unsightly tumours to grow on the animal's face and mouth, leaving them unable to feed.

They die from starvation and a breakdown in bodily functions.

Nano-zinc yields clearer fingerprints

Mon, 07 Jul 2008 02:16:13 GMT

clipped by: pokkets

Clip Source: www.abc.net.au

A powder made up of zinc oxide nanoparticles can give crime fighters a clearer image of fingerprints, even on wet surfaces, say Australian researchers.

Dr Andrew McDonagh and colleagues, of the Centre for Forensic Science at the University of Technology, Sydney (UTS), report their findings in the Journal of Material Science.

McDonagh says traditional powder reveals fingerprints by sticking to the oily residues left on the surface - but this doesn't always work

on wet surfaces such as sinks or bath tubs, especially when part of the print has been washed away

Working with the Australian Federal Police, McDonagh and team tested a new fingerprint powder based on zinc oxide nanoparticles on surfaces such as glass, polyethylene and aluminium.

When illuminated with ultraviolet light the nanoparticles fluoresce without the addition of any fluorescent dyes.

Compared to conventional powders the researchers found the zinc oxide nanoparticle powder gave a much clearer picture of the fingerprints

Call to encourage climate-friendly farms

Fri, 04 Jul 2008 16:00:03 GMT

clipped by: pokkets

Clip Source: www.abc.net.au

Anna Salleh

News analysis Australian farmers could have a huge impact on greenhouse emissions and the government needs to start seriously encouraging them to sequester carbon in their soils, say some experts.

The comments come as the Garnaut Climate Change Review delivers a draft report, which acknowledges changing the way we farm can have a big impact on our greenhouse emissions.

Professor Peter Grace of the Queensland University of Technology, an expert on agriculture and greenhouse emissions, estimates that in an ideal situation, more than 900 Megatonnes of CO2 equivalents could be sequestered per annum through improved pasture management.

It's a very significant amount of carbon

even if only 10% of this amount was achieved it would result in a significant reduction in Australia's carbon emissions.

John Connor of the Climate Institute says the government should give some signal to encourage farmers to sequester carbon in its Green Paper on emissions trading, due out on 16 July.

Carbon specks push back origins of life

Fri, 04 Jul 2008 07:28:45 GMT

clipped by: pokkets

Clip Source: www.abc.net.au

Anna Salleh

Tiny traces of carbon trapped inside the oldest diamonds ever found, suggest life started on Earth 700 million years earlier than previously thought, say Australian researchers.

Dr Alexander Nemchin and colleagues from Curtin University's Department of Applied Geology in Western Australia report their findings in this week's issue of Nature.

The team analysed carbon isotopes trapped inside the 4.2-billion year old diamonds that formed inside zircon crystals discovered last year in the Jack Hills region of Western Australian.

Associate Professor Ian Fitzsimons, who heads the department that Nemchin and colleagues belong to, says the ratio of carbon isotopes provides clues on whether the carbon came from a life form.

"When plants take in carbon from the atmosphere they much prefer carbon-12 and don't like carbon-13," says Fitzsimons.

"So the carbon in the plants has a different ratio and anything that eats the plants inherits that ratio."

Chance discovery sheds light on S.I.D.S.

Fri, 04 Jul 2008 04:19:26 GMT

clipped by: pokkets
clipper's remarks: Cot death, or Sudden Infant Death Syndrome has been a mystery, and a number of causes have studied. It has also been suggested that there may be more than one cause. While the study was on mice, they hope it will lead to more clues in the search for causes in humans, and help identify babies at risk

Clip Source: www.abc.net.au

An imbalance of a key brain chemical could be the cause of cot death, after a chance discovery by researchers in Italy.

The team, based at the European Molecular Biology Laboratory, found that an out of balance self-regulating system controlling the nerve-signalling chemical serotonin in the brainstem, caused sudden death in mice.

Writing in the journal Science, they hope their experiment will help doctors pinpoint human babies at high risk of cot death, also known as Sudden Infant Death Syndrome (SIDS).

While the researchers say it is unlikely the molecular mechanism is the same in humans, they believe their findings may one day help identify babies at greatest risk.

"Ultimately, we hope it will give new ideas to doctors about how to diagnose babies at risk for SIDS," says Dr Enrica Audero

Genetically engineered mice whose self-regulating serotonin system was turned off did not die, showing it was worse to have a malfunctioning system than no system at all, the study says.

Teen years officially a pain in the neck.

Thu, 03 Jul 2008 06:31:45 GMT

clipped by: pokkets
clipper's remarks: Posture is commonly blamed, but many things are thought to contribute to neck and back pain. Perhaps even that the pain is contributing to the bad posture.

Clip Source: www.abc.net.au

Dani Cooper

Australian researchers have proven what high school students have long suspected, being a teenager can be a real pain in the neck.

A survey of 1593 West Australian 14-year-olds has shown that one in 20 suffer prolonged neck and shoulder pain.

And, according to lead researcher Professor Leon Straker, almost half of all adolescents experience neck and shoulder pain at some time.

The findings, published recently in the journal Manual Therapy show neck and shoulder pain is far more common among teenagers than previously thought.

Straker and his team at Curtin University of Technology's School of Physiotherapy, the National Health and Medical Research Council-funded project has also cast doubt on theories that the pain is primarily caused by posture.

"Our study shows that posture is only one small part of a bigger picture."

Straker says his team believes the pain is the result of "interactions between different things".

These include

depression, lifestyle and physical characteristics

Extinction risks 'underestimated'

Thu, 03 Jul 2008 06:20:30 GMT

clipped by: pokkets

Clip Source: www.abc.net.au

Some endangered species may face an extinction risk that is up to a hundred times greater than previously thought, according to a new study.

The study, which appears in Nature, says researchers may have badly underestimated the perils confronting threatened wildlife by overlooking random differences between individuals in a given population.

Many larger populations previously considered relatively safe would actually be at risk," says study lead author Professor Brett Melbourne from University of Colorado

more than 16,000 species worldwide threatened with extinction, according to the International Union for Conservation of Nature

One in four mammals, one in eight birds and one in three amphibians are on the IUCN's endangered species "Red List".

current models

typically look only at two risk factors

individual deaths

and

environmental conditions

other determinants must be taken into account: male-to-female ratios in a species, and a wider definition of randomness in individual births and deaths

Spiritual effects of 'magic' mushies linger

Wed, 02 Jul 2008 05:54:17 GMT

clipped by: pokkets
clipper's remarks: Strict supervision of its use is the key, the researchers note, warning that it should not be given to people at risk for psychosis or certain other serious mental disorders
Psilocybin has been condemned by the law, and 'society' (We all know how credible they are)
It has never been condemned objectively - by science.
No subjects reported any lingering harmful effects, and no clinical evidence of harm was observed. Of the volunteers who took the one-day test of psilocybin, 22 of the 36 had a "complete" mystical experience, based on a detailed questionnaire. 67% rated it among the five most spiritually significant experiences of their lives

Clip Source: www.abc.net.au

Maggie Fox

The effects of psilocybin from so-called magic mushrooms last for more than a year, and may offer a way to help patients with fatal diseases or addictions, according to US researchers.

The findings, which appear in the Journal of Psychopharmacology, follow on from a previous study, which examined the immediate effects of administering psilocybin.

In 2006, Roland Griffiths of Johns Hopkins University in Baltimore, and colleagues gave psilocybin to 36 volunteers, "Under very defined conditions, with careful preparation".

About a third of the volunteers experienced fear and anxiety after taking the psilocybin, but most later reported having a "mystical" or "spiritual" experience.

A year later, more than half of the participants still said the experience increased their sense of well-being or life satisfaction, the researchers write.

"Rarely in psychological research do we see such persistently positive reports from a single event in the laboratory."

Male tuataras face dateless futures

Wed, 02 Jul 2008 04:35:04 GMT

clipped by: pokkets
clipper's remarks: Like many reptiles the ratio of males to females depends on the temperature.
Many more creatures depend on a relatively stable temperature range to remain viable. All are part of a food chain. If a link is knocked out, the predator can starve, and the prey overpopulate. Evolution is a relatively slow process. If change happens too quickly, the creatures don't have time to adapt, and the link is knocked out. This can lead to the collapse of the food chain.

Clip Source: www.abc.net.au

Dani Cooper

The male tuatara will be increasingly desperate and dateless as global warming leads to less female hatchlings being born by 2085, Australian researchers are predicting.

Future prospects ... climate change modelling shows solo male tuataras may be the norm by 2085 at North Brother Island

Writing in today's Proceedings of the Royal Society B, the researchers say their finding highlights the need for ways to predict climate change impacts in animals where sex of offspring is temperature determined.

Lead author Dr Nicola Mitchell, of the Centre for Evolutionary Biology at the University of Western Australia, says their modelling shows human intervention will be needed to save the endangered tuatara from extinction.

the sex of offspring in the cold-blooded reptile is, like in many egg-laying reptiles, determined by the temperature during a short period of its embryonic development

tuatara is one of the few reptiles where males are exclusively produced as the temperature rises

Gene Editing Could Make Anyone Immune to AIDS

Tue, 01 Jul 2008 16:31:20 GMT

clipped by: wildcat

Clip Source: blog.wired.com

Some people have a mutation that makes them amazingly resistant to HIV -- and now, scientists may have found a way to give that immunity to anyone.

Viruses enter cells and take them over, but to get inside, they need a handhold. HIV pulls itself in by grabbing onto a protein called CCR5, which decorates the surface of T-cells, which are one of the two major types of white blood cells and play an important role in helping the body fight infections. Back in the 1990's, researchers took interest in a handful of promiscuous gay men who were able to engage in sexual relations with their HIV-positive partners with impunity. Most of them had a mutation that kept their cells from producing normal CCR5 protein.

Armed with that knowledge, scientists have developed several tactics to block the production of CCR5 or perturb its shape so that the HIV virus can't grab onto it during the first step of its hijacking attempt

Tags: dna, hiv, immunity, viruses

Study blows whistle on ref's fitness.

Tue, 01 Jul 2008 10:39:24 GMT

clipped by: pokkets
clipper's remarks: The referee must keep up with the fastest player, for the whole match. The players take turns to score points, and spread the load between the team. The referee not only has to keep up, but never take their eye off the ball. Not only that, if a team loses, they can get the blame.
If you can't play become a referee? More like the other way around.

Clip Source: www.abc.net.au

Dani Cooper

Referees give the sports people they preside over a run for their money quite literally, an Australian sports science expert says.

But when age catches up with them, some will "cheat" to help them keep control over the game, Dr Anthony Leicht, of the Institute of Sport and Exercise Science at James Cook University

Leicht says his study of elite basketball referees, published in a recent Journal of Science and Medicine in Sport, shows they are working just as hard as the players.

"In basketball it is a small enclosed court and the general feeling was that referees stand around a lot," Leicht says.

For the study, Leicht monitored heart rates of seven elite-level basketball referees during a pre-Olympics tournament in the lead-up to the 2004 Athens Games.

He found the referees worked at an average heart rate of 150 beats per minute (plus or minus 18bpm) for each quarter of the match.

The referees on average ran between five and seven kilometres per game.