viernes, 1 de agosto de 2014

Stick insect leads antibiotic hunt

A microbe in the gut of a stick insect could help scientists to unravel the puzzle of antibiotic resistance. The Giant Lime Green stick insect, which feeds mainly on eucalyptus leaves, is being studied at the John Innes Centre (JIC) in Norwich.

Self-study activity:
Watch this short BBC News item and answer the questions below about it


1 Why would patients risk dying from simple operations in the near future?
2 Name two medical treatments that are in high risk.
3 What are the two main difficulties to find new drugs?
4 How do the South American leaf cutter ants protect from the bacteria and fungus that contaminate their fungus garden?
5 Why aren't antibiotics a good investment for drug companies?
6 Why is it too late already for a lot of patients?

To check your answers, you can read the transcript below.

In just a few years’ time our hospitals could become dangerous places for patients, with many people dying from simple operations. The reason is that common infections are becoming more and more resistant to antibiotics (1).
Hip replacements, knee replacements would become much more risky because of the risk of untreatable infection developing afterwards, and also some cancer treatments (2) like bone marrow transplants would become completely impossible.
There’s now real urgency to find new drugs. The problem is it’s very difficult and incredibly expensive (3). It’s led scientists from around the world to look for cures in some unlikely places.
Oh, wow, it’s totally a different world. Well I can see the colony of ants, but they are a lot bigger than the ones we get here in the UK.
Indeed, these are leaf cutter ants which come from the New World, come from South America. When these ants build a nest, they create a fungus garden. That is a fungus that they feed to their larvae and it’s created by chewing up leaf material, and the fungus grow on that. And they maintain it, and the fungus can become contaminated by unwanted bacteria and fungus, so the ants culture a bacteria on their bodies which they can actually use to control the unwanted bacteria and fungus that can grow within a fungus garden.
Basically these ants are creating their own antibiotics? (4)
Antibiotics are not a money spinner for drug companies. They cost a fortune to develop and there’s no guarantee they’ll get a return on their investment. The risk is that after a few years their new antibiotics might not be effective anymore (5).
We are commercial entities, but we do have a moral obligation to play our part in solving the problem. We have the knowledge, we have a huge amount of knowledge in our organizations. We need to share that creatively. We need to work with various other agencies to get these new medicines made available for the doc to use appropriately.
Scientists are now harvesting the antibiotics the ants produce. It’s still early days, but the team are quietly confident.
I think realistically if we look hard enough that we are going to find novel antibiotics produced by the bacteria living on these ants, they will be useful in human medicine. In a sense it’s too late already because there are lots of multi-drug resistant bacteria that you can't treat with antibiotics any more (6). At the moment, it’s a small problem, so a small minority of people in the world suffer, but in the future if we don’t discover new antibiotics, then we’re going to be in big trouble.