Monash University researchers are shedding light on the complex processes that underpin the creation and differentiation of stem cells, bringing closer the promise of ‘miracle’ therapies.

Dr Jose Polo of the Australian Regenerative Medicine Institute (ARMI) and the Department of Anatomy and Developmental Biology and his team, with collaborators at Harvard, have comprehensively mapped, for the first time, the process by which mature cells are re-programmed to become an induced pluripotent stem (iPS) cell.

iPS cells behave almost exactly like embryonic stem cells - they can become any cell in the body - but come without the ethical and scientific pitfalls.

The re-programming process was developed in 2006; however, until now, it was unknown exactly how it worked.

Dr Polo has unravelled the precise molecular events occurring in an adult skin cells at almost every level throughout the re-programming process. The results were published in the prestigious journal Cell.

Every cell in the body contains a full genome or complete set of DNA. The differences between a brain neuron and a liver cell are down to the fact that although they contain the exact same genes, not all of these are active in each cell - a process known as transcription.

Proteins called transcription factors control which genes are active or inactive by changing the availability of the genes to be transcribed. This in turn mediates  the differentiation of stem cells to all the different types of cells in the body. It is the reversal of this complex process - returning an adult cell to its pluripotent state - that the researchers mapped.

"Once you understand a process, you can manipulate it," Dr Polo said.

"Now that we have created a roadmap for re-programming, we can do a lot of things. We can look at improving the efficiency of re-programming and investigating if some of the potential dangers can be avoided by re-routing the process."

Now, Dr Polo's team is investigating whether re-programming follows an identical path for all types of cells. They are also looking at the potentially cancer-causing mutations in iPS cells and ways to circumvent this tumorific potential.

Another project is examining "memory" in iPS cells and its implications.

"For example, if I create an iPS cell from a blood cell and an iPS cell from a muscle cell, the two are a little different - they carry memories of where they were generated. Now I'm examining ways to exploit these memories," Dr Polo said.

Dr Polo said these and many more complexities must be understood before stem cell therapy can move effectively into the clinical arena.

"Modern medicine has achieved wonderful things, but doctors are like mechanics trying to fix a car without access to spare parts," Dr Polo said.

"The promise of stem cells is amazing - it will almost bring us into a new age of medicine - but there's a lot more work to do before this promise can be realised."

Parents who share a bed with their breastfed baby could face a fivefold increase in the risk of crib death, even if the parents do not smoke, according to a new study. The research was led by the London School of Hygiene & Tropical Medicine and is published in BMJ Open. Crib death -- also known as cot death or sudden infant death syndrome (SIDs) -- remains a major cause of death among babies under 1 year of age in high income countries. There is already a general consensus that sleeping with a baby increases the risk of cot death if the parents smoke or if the mother has been drinking alcohol or taking drugs. However, there are conflicting opinions as to whether bed sharing in general represents a risk when these factors are not present.

Some countries, including the US and the Netherlands, advise all parents against sharing a bed with their baby for the first 3 months. The UK currently only advises certain groups, including parents who are smokers, not to bed share.

The new study is the largest ever analysis of its kind. Researchers examined the individual records of 1,472 cot death cases and 4,679 control cases across five major studies. They found that the risk of cot death among breastfed babies under 3 months increased with bed sharing, even when the parents did not smoke and the mother had not consumed alcohol or drugs. This fivefold increase was in comparison to room sharing, where a baby slept in a cot in the parents' room.

The researchers estimate that 81% of cot deaths among babies under 3 months with no other risk factors could be prevented if they did not sleep in the same bed as their parents. The study also showed that the risk associated with bed sharing decreases as a baby gets older, and that the peak period for instances of cot death was between 7 and 10 weeks.

Professor Bob Carpenter from the London School of Hygiene & Tropical Medicine who was lead author on the study said: "Currently in the UK more than half of cot deaths occur while a baby is sleeping in the same bed as its parents. Although it is clear that smoking and drinking greatly increase the risk of cot death while bed sharing, our study shows that there is in fact an increased risk for all babies under 3 months who bed share, even if their parents do not smoke or drink.

"If parents were made aware of the risks of sleeping with their baby, and room sharing was instead promoted in the same way that the 'Back to Sleep' campaign was promoted 20 years ago to advise parents to place their newborn infants to sleep on their backs, we could achieve a substantial reduction in cot death rates in the UK. Annually there are around 300 cot death cases in babies under a year old in the UK, and this advice could save the lives of up to 40% of those. Health professionals need to make a definite stand against all bed sharing, especially for babies under 3 months."

The authors state that babies can still be brought into the parents' bed for comfort and feeding during the night, but that they should be placed in a cot next to the parents' bed to sleep.

Little is known about the effect of physical education (PE) on child weight, but a new study from Cornell University finds that increasing the amount of time that elementary schoolchildren spent in gym class reduces the probability of obesity. The study represents some of the first evidence of a causal effect of PE on youth obesity, and is forthcoming in the Journal of Health Economics.

The research offers support for the recommendations of organizations such as the Centers for Disease Control, Institute of Medicine, and the American Academy of Pediatrics, all of which have advocated increasing the amount of time that elementary school children spend in gym class, says lead researcher and Cornell professor of policy analysis and management, John Cawley, who conducted the study with Chad Meyerhoefer of Lehigh University (Cornell Ph.D. 2002) and David Frisvold of Emory University.

Treating variation in the amount of time that states mandate schoolchildren spend in PE as natural experiments, the researchers found that an additional 60 minutes per week of PE time (enough to bring states without an explicit requirement up to the amount of PE recommended by the CDC) reduces the probability that a fifth-grader is obese by 4.8 percentage points.

The researchers also detected a gender difference: additional PE time reduces weight for boys but has a negligible effect for girls. One explanation for this difference, says Cawley, is that PE and other types of physical activity are complements for boys (increased PE leads boys to be more active in structured physical activities like organized sports), but substitutes for girls (increased PE leads girls to spend more time watching television).

Waterproof fabrics that whisk away sweat could be the latest application of microfluidic technology developed by bioengineers at the University of California, Davis. The new fabric works like human skin, forming excess sweat into droplets that drain away by themselves, said inventor Tingrui Pan, professor of biomedical engineering. One area of research in Pan's Micro-Nano Innovations Laboratory at UC Davis is a field known as microfluidics, which focuses on making "lab on a chip" devices that use tiny channels to manipulate fluids. Pan and his colleagues are developing such systems for applications like medical diagnostic tests.

Graduate students Siyuan Xing and Jia Jiang developed a new textile microfluidic platform using hydrophilic (water-attracting) threads stitched into a highly water-repellent fabric. They were able to create patterns of threads that suck droplets of water from one side of the fabric, propel them along the threads and expel them from the other side.

"We intentionally did not use any fancy microfabrication techniques so it is compatible with the textile manufacturing process and very easy to scale up," said Xing, lead graduate student on the project.

It's not just that the threads conduct water through capillary action. The water-repellent properties of the surrounding fabric also help drive water down the channels. Unlike conventional fabrics, the water-pumping effect keeps working even when the water-conducting fibers are completely saturated, because of the sustaining pressure gradient generated by the surface tension of droplets.

The rest of the fabric stays completely dry and breathable. By adjusting the pattern of water-conducting fibers and how they are stitched on each side of the fabric, the researchers can control where sweat is collected and where it drains away on the outside.

Workout enthusiasts, athletes and clothing manufacturers are all interested in fabrics that remove sweat and let the skin breathe. Cotton fibers, for example, wick away sweat — but during heavy exercise, cotton can get soaked, making it clingy and uncomfortable.

A paper describing the research was published recently in the journal Lab on a Chip. The work was funded in part by the National Science Foundation.