Australian Science

Tag: Pharmaceutical

  • Combating the rise of the superbugs: The health and scientific challenges of antibiotic resistance

    Combating the rise of the superbugs: The health and scientific challenges of antibiotic resistance

    It’s hard to imagine the world prior to antibiotics, a world where even a deep laceration could frequently spell significant illness or even death due to infection. Thankfully, since the discovery of penicillin in 1929 by Alexander Fleming, we now have a range of potent antibiotics to treat many of the various types of bacterial infection.

    There is a problem though, bacteria are great survivors and have been competing against other bacteria and microorganisms for billions of years. As  Professor Matt Cooper from the University of Queensland  puts it “Billions of years ago, bacterial species were engaged in an arms race against each other and the chemicals they developed to kill one another have been modified into today’s antibiotics”.1

    Multi-Drug resistant Tuberculosis is a particular concern for health authorities and clinicians due to limited treatment options.

    Unfortunately it’s our overuse of these important drugs which has driven the rapid development of antibiotic resistance, the process whereby bacteria containing mutations in their DNA, that provide some protection from an  antibiotic, have an enormous survival advantage when exposed to the antibiotic and pretty soon dominate. Frequent exposures to the antibiotic may further strengthen these survival traits via the selection process, rendering the the drug less effective over time. It’s a great example of random variations leading to non-random adaptions through natural selection, although one with profound consequences for human health.

    Of particular concern are bacteria that have developed resistance to multiple types of antibiotics, resulting in particularly dangerous resistant bacteria such as the multi-drug resistant variants of tuberculosis, that are extremely difficult to treat. Indeed leading health authorities are so worried about the problem that the Chief Medical Officer of the UK, Professor Dame Sally Davies, has recently labelled the threat as “catastrophic

  • An outdated appetite control system in a rapidly evolving world?

    An outdated appetite control system in a rapidly evolving world?

    Imagine yourself for a moment waiting for a meal at your favourite restaurant, local takeaway store or at home counting down the time until the oven buzzer sounds. You know you’re hungry, but we seldom think or care about the complex series of processes that go on inside our bodies that drive that hunger.

    And why should we care?

    In the developed world, for the lucky majority at least, calorie-dense food has never been more accessible. Want a pizza? Just use an app from your smartphone to order one delivered any time, day or night. The one big problem with this–human appetite has evolved over tens of thousands of years when food was tough to come by, and we had to work physically hard for a meal, now we just go to the fridge. However the series of long developed processes that drive appetite have not caught up in this time of plenty thereby contributing to the modern day upsurge in obesity.

    Obesity as a global problem

    Obesity is a global disease on the increase, the World Health Organisation estimates that by 2015 there will be an astounding 700 million adults classified as obese. From a health viewpoint this is particularly worrying as obesity is a major risk factor for cardiovascular diseases, Type-2 diabetes and some cancers.

    Also concerning, is the number of people in developing countries at risk, where the bane of obesity joins established under-nutrition. Dr Ranjan Yajnik, the director of the diabetes unit at King Edward Memorial Hospital in Pune, was recently reported by ABC News saying, “Populations which have faced under-nutrition for a long time are now exposed to the over-nutrition of the modern world through globalisation and westernisation”.

    In short, it’s the modern world and how we live in it which is driving up rates of obesity.

    An unbalanced system?

    In broad terms, the body is wired to protect against starvation and low food availability, by increasing biological and sensory processes that promote the need to eat. This makes sense, after all starvation is an immediate threat to survival and was by far one of the greatest concerns of our ancient ancestors. As excessive food was less of a concern, the regulatory processes to protect against excess consumption and weight gain appear less effective, leading to the body favouring weight gain over weight loss.
    Combine this with the increased availability of highly palatable foods, and the ability to stop eating when full is increasingly difficult. According to Dr. Joanne Harrold and colleagues, in a recent paper published in the journal Neoropharmacology, this may be especially true for many obese people, who may “possess an over-responsiveness to the reward effects of eating, which results in the appetite system of these people being effectively overwhelmed