Mane event: horse placenta has been used to treat footballers’ injuries. Photo: Getty
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The placenta is a marvel that scientists can’t match

Nothing we can engineer has come close to replicating the placenta’s ability to act as the kidney, lungs, hormone source, nutrition channel and waste disposal unit for a growing foetus.

The unwritten rules of journalism will ensure that, for the next month, few stories will be able to string together more than 500 words without mentioning the World Cup. Luckily, Spain’s Diego Costa has used horse placenta to treat an injury; this, he claims, allowed him to recover in time for the Champions League final and be fully fit for Rio. It’s also why we can now discuss the idea for the Human Placenta Project.

At the end of last month, placenta experts (research scientists, not people who drip horse placenta extract on to desperate athletes) gathered in Maryland in the US. Their aim was to establish a project to learn how this most understudied of organs works – and what to do when it doesn’t.

Questionable medical applications aside, the placenta is a marvel. You wouldn’t be here without it. Although scientists have been trying for decades to create artificial versions, they have failed miserably. Nothing we can engineer has come close to replicating the placenta’s ability to act as the kidney, lungs, hormone source, nutrition channel and waste disposal unit for a growing foetus.

That said, not all placentas are created equal. And yet we have no scientific definition of the ideal placenta, which makes it very hard to diagnose a faulty one. Placentas that have nurtured babies who have been born weak or sick often look entirely normal. Abnormal-looking placentas are frequently associated with healthy babies. The devil, it seems, is in the detail.

The placenta grows from a layer of cells that surrounds the early foetus. These cells attach themselves to the wall of the uterus and then develop a network of tiny blood vessels that tap into the uterine blood supply, while also maintaining a barrier between the two organisms to stop the foetus from triggering the mother’s immune system. The mother-foetus connection doesn’t always work perfectly. Sometimes the placenta doesn’t attach properly or is too small to provide all the nutrition the baby needs, which can cause a range of medical problems for the mother-to-be and the foetus, often necessitating early delivery.

It can take years for some results of placental problems to manifest. Studies have shown that an abnormal placenta is linked to health issues in later life such as heart disease and diabetes. That’s because if the foetus gets too little nutrition, it builds budget versions of vital organs and tissues. Kidneys will have fewer of the nephrons that do its filtering work. The heart will have fewer muscle cells and the pancreas will skimp on insulin-producing ones.

The Human Placenta Project might do more than lead to healthier births. Understanding exactly how the placenta keeps the foetus from rejection by the pregnant mother is of great interest to the field of transplant surgery, for instance.

It could also help in the fight against cancer. Many cancers contain proteins created by a gene called PLAC1. In normal tissue, this gene is inactive; it is usually switched on only in placental tissue. PLAC1 has been found in tumours taken from breast, ovarian and prostate cancer cells and has recently been found to be active in tumours – mainly stomach cancers and lymphomas – caused by the Epstein-Barr virus. We would do well to find out why.

The answers to this and other questions about the placenta are most likely to be found through closer study of an organ that hospitals (excluding horse hospitals, it seems) routinely send to the incinerator. 

Michael Brooks holds a PhD in quantum physics. He writes a weekly science column for the New Statesman, and his most recent book is At the Edge of Uncertainty: 11 Discoveries Taking Science by Surprise.

This article first appeared in the 18 June 2014 issue of the New Statesman, Islam tears itself apart

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Air pollution: 5 steps to vanquishing an invisible killer

A new report looks at the economics of air pollution. 

110, 150, 520... These chilling statistics are the number of deaths attributable to particulate air pollution for the cities of Southampton, Nottingham and Birmingham in 2010 respectively. Or how about 40,000 - that is the total number of UK deaths per year that are attributable the combined effects of particulate matter (PM2.5) and Nitrogen Oxides (NOx).

This situation sucks, to say the very least. But while there are no dramatic images to stir up action, these deaths are preventable and we know their cause. Road traffic is the worst culprit. Traffic is responsible for 80 per cent of NOx on high pollution roads, with diesel engines contributing the bulk of the problem.

Now a new report by ResPublica has compiled a list of ways that city councils around the UK can help. The report argues that: “The onus is on cities to create plans that can meet the health and economic challenge within a short time-frame, and identify what they need from national government to do so.”

This is a diplomatic way of saying that current government action on the subject does not go far enough – and that cities must help prod them into gear. That includes poking holes in the government’s proposed plans for new “Clean Air Zones”.

Here are just five of the ways the report suggests letting the light in and the pollution out:

1. Clean up the draft Clean Air Zones framework

Last October, the government set out its draft plans for new Clean Air Zones in the UK’s five most polluted cities, Birmingham, Derby, Leeds, Nottingham and Southampton (excluding London - where other plans are afoot). These zones will charge “polluting” vehicles to enter and can be implemented with varying levels of intensity, with three options that include cars and one that does not.

But the report argues that there is still too much potential for polluters to play dirty with the rules. Car-charging zones must be mandatory for all cities that breach the current EU standards, the report argues (not just the suggested five). Otherwise national operators who own fleets of vehicles could simply relocate outdated buses or taxis to places where they don’t have to pay.  

Different vehicles should fall under the same rules, the report added. Otherwise, taking your car rather than the bus could suddenly seem like the cost-saving option.

2. Vouchers to vouch-safe the project’s success

The government is exploring a scrappage scheme for diesel cars, to help get the worst and oldest polluting vehicles off the road. But as the report points out, blanket scrappage could simply put a whole load of new fossil-fuel cars on the road.

Instead, ResPublica suggests using the revenue from the Clean Air Zone charges, plus hiked vehicle registration fees, to create “Pollution Reduction Vouchers”.

Low-income households with older cars, that would be liable to charging, could then use the vouchers to help secure alternative transport, buy a new and compliant car, or retrofit their existing vehicle with new technology.

3. Extend Vehicle Excise Duty

Vehicle Excise Duty is currently only tiered by how much CO2 pollution a car creates for the first year. After that it becomes a flat rate for all cars under £40,000. The report suggests changing this so that the most polluting vehicles for CO2, NOx and PM2.5 continue to pay higher rates throughout their life span.

For ClientEarth CEO James Thornton, changes to vehicle excise duty are key to moving people onto cleaner modes of transport: “We need a network of clean air zones to keep the most polluting diesel vehicles from the most polluted parts of our towns and cities and incentives such as a targeted scrappage scheme and changes to vehicle excise duty to move people onto cleaner modes of transport.”

4. Repurposed car parks

You would think city bosses would want less cars in the centre of town. But while less cars is good news for oxygen-breathers, it is bad news for city budgets reliant on parking charges. But using car parks to tap into new revenue from property development and joint ventures could help cities reverse this thinking.

5. Prioritise public awareness

Charge zones can be understandably unpopular. In 2008, a referendum in Manchester defeated the idea of congestion charging. So a big effort is needed to raise public awareness of the health crisis our roads have caused. Metro mayors should outline pollution plans in their manifestos, the report suggests. And cities can take advantage of their existing assets. For example in London there are plans to use electronics in the Underground to update travellers on the air pollution levels.

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Change is already in the air. Southampton has used money from the Local Sustainable Travel Fund to run a successful messaging campaign. And in 2011 Nottingham City Council became the first city to implement a Workplace Parking levy – a scheme which has raised £35.3m to help extend its tram system, upgrade the station and purchase electric buses.

But many more “air necessities” are needed before we can forget about pollution’s worry and its strife.  

 

India Bourke is an environment writer and editorial assistant at the New Statesman.