Thursday, August 23, 2012

Green tea extract 'eradicates cancer tumours'

A very preliminary study in laboratory glassware only

Powerful new anti-cancer drugs based on green tea could soon be developed after scientists found an extract from the beverage could make almost half of tumours vanish.  The University of Strathclyde team made 40 per cent of human skin cancer tumours disappear using the compound, in a laboratory study.

Green tea has long been suspected of having anti-cancer properties and the extract, called epigallocatechin gallate, has been investigated before.  However, this is the first time researchers have managed to make it effective at shrinking tumours.

Previous attempts to capitalise on its cancer-fighting properties have failed because scientists used intravenous drips, which failed to deliver enough of the extract to the tumours themselves.

So, the Strathclyde team devised a “targeted delivery system”, piggy-backing the extract on proteins that carry iron molecules, which cancer tumours Hoover up.  The lab test on one type of human skin cancer showed 40 per cent of tumours disappeared after a month of treatment, while an additional 30 per cent shrank.

Dr Christine Dufès, a senior lecturer at the Strathclyde Institute of Pharmacy and Biomedical Sciences, who led the research, said: “These are very encouraging results which we hope could pave the way for new and effective cancer treatments.

“When we used our method, the green tea extract reduced the size of many of the tumours every day, in some cases removing them altogether.  "By contrast, the extract had no effect at all when it was delivered by other means, as every one of these tumours continued to grow.

“This research could open doors to new treatments for what is still one of the biggest killer diseases in many countries.”  She added: “I was expecting good results, but not as strong as these.”

Dr Dufès said population studies had previously indicated that green tea had anti-cancer properties, and scientists had since identified the active compound as epigallocatechin gallate.

But the Strathclyde researchers were the first to delivery it in high enough doses to tumours to have an effect.

She explained: “The problems with this extract is that when it’s administered intravenously, it goes everywhere in the body, so when it gets to the tumours it’s too diluted.  “With the targeted delivery system, it’s taken straight to the tumours without any effect on normal tissue.”

Cancer scientists are increasingly using targeted delivery to improve results, relying on the many different ‘receptors’ that tumours have for different biological substances.

In this instance, the scientists used the fact that tumours have receptors for transferrin, a plasma protein which transports iron through the blood.

The results have been published in the journal Nanomedicine.

The “ultimate objective” was a clinical trial in humans - but Dr Dufès said that was some way off.  “We have got to optimise the delivery system and therapeutic effect first,” she said.

Dr Julie Sharp, from Cancer Research UK, said: “A few studies have shown that extracts from green tea may have some effect on cancer cells in the lab but this has not yet been backed up by research in humans.”  She added: “It’s far too soon to say if enjoying a cup of green tea has any wider benefits in combating cancer but we know that a healthy balanced diet can help to reduce the risk.”


Midwives told to drop ‘30-second rule’ on cutting umbilical cord after delaying longer shown to benefit babies

This has been known for some time.  It seems a pity that it is not already generally implemented

A radical change in the way babies are delivered will see midwives delay cutting the umbilical cord following evidence that it improves the health of newborns.

The Royal College of Midwives is preparing to update its guidance  to recommend delayed clamping  for most women who give birth in hospitals, which will affect about  90 per cent of all births.

Current guidance from the RCM  and the National Institute for Health and Clinical Excellence is to cut and clamp the umbilical cord within  30 seconds to protect babies from too much exposure to a synthetic hormone given to mothers to speed up labour and deliver the placenta.

It was also thought to help prevent a baby getting jaundice, a condition that causes yellowing of the skin, and was encouraged because of the risk of bleeding in new mothers.

However, doctors have long been divided over the issue – and studies have now found that delaying the procedure by just a few minutes has significant health benefits.

It is thought being connected to the maternal blood supply for longer helps protect babies against iron deficiency and anaemia, and allows vital stem cells to  be transferred.

Increasing numbers of women have also been asking midwives to delay cutting and clamping to allow more blood to drain from the placenta into the baby, and also simply so they are connected for longer.

The new guidance is being developed and will be announced at the  College’s conference in November.

Mervi Jokinen, practice and standards development adviser at the RCM, said: ‘We are supporting the midwives not to clamp the cord immediately. We’ve not finalised the guidelines and in terms of how long it will recommend delaying clamping for, we don’t know.

‘Guidelines drawn up by different organisations vary from one to five minutes, and even up to ten.

‘Most midwives will have to use  their judgment in terms of the clinical situation. It’s more likely to happen within three to five minutes.’

Mrs Jokinen added that the change was driven by the evidence from  clinical studies, but also because women were increasingly asking for midwives to delay clamping.

‘The issue here was studies started to show that with early clamping you’re denying a baby a boost of blood and it was recognised that haemoglobin levels were much lower later on,’ she said.

‘It is said that babies who are healthy and well would benefit  from greater haemoglobin levels. Women have also asked us to give their babies to them while they  are attached.’

A study from Sweden found a delay of three minutes could reduce the risk of iron deficiency later in childhood as well as anaemia in newborns, which can lead to poor brain development.

At four months, fewer than one per cent of infants who had delayed clamping were deficient in iron compared with six per cent of those clamped immediately.  There was no increase in jaundice or other complications thought to be linked to delayed clamping.

In an editorial published in the same journal as the study, Dr Patrick van Rheenen, a consultant paediatrician at Groningen University in the Netherlands, said: ‘Delayed clamping clearly favours the child.

‘How much evidence is needed to convince obstetricians and midwives that it is worthwhile to wait for three minutes to allow for placental transfusion?’

A major US study published in 2007, which involved more than 1,900 newborns, found a two-minute delay was enough to reduce the  risk of anaemia by half and low iron levels in the blood by a third.

The World Health Organisation dropped early clamping from its guidelines in 2007 and best practice on the issue varies across Europe.  Guidelines in the UK, drawn up by NICE, recommend early clamping although an update is due in 2014.

The Royal College of Obstetricians and Gynaecologists updated its guidance last year to recommend the cord ‘should not be clamped earlier than necessary, based on a clinical assessment of the situation’.

Although hospitals will still be able to decide their own birth protocols, it is likely that they will  follow RCM policy.

David Hutchon, a retired consultant obstetrician and gynaecologist  who has campaigned for years for a change in policy, said: ‘This is very welcome.  ‘But whether doctors will take any notice is another issue.  ‘There’s a lot of ignorance out  there and people have just blindly  followed guidance for years without questioning it.’


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