Science has been demonstrating the value of a broad education. Let’s start with classics. If you’ve read your Herodotus you’ll know that Persian kings insisted on drinking water that was transported in silver containers because they would keep the water fresh. The water supplies on the International Space Station are fed through silver for exactly the same reason.
Now, nearly two and a half thousand years after Hippocrates described the healing properties of silver, we know how it works. A team at Boston University has shown that, when dissolved, silver ions will get inside the bacterium and send its oxygen-generating machinery into overdrive, making the bug self-destruct.
Clearly, dissolved silver ions have been doing a great job throughout history and we can now expect even more. The Boston team showed that silver ions will also lever open the membranes surrounding various microbes, allowing antibiotic medicines to penetrate the bug’s defences. A dose of silver seems to disable many bugs’ resistance to our drugs: there is now talk of the ancients’ antibiotic getting us out of the terrifying growth of antibiotic resistance.
It’s worth sounding a note of caution here. For years, proponents of alternative medicine have been pushing “colloidal silver”, a suspension of microscopic silver particles, as a treatment for everything from cancer to haemorrhoids. However, European regulators and the US Food and Drug Administration have banned any over-the-counter sales because in most scenarios the best it will do is turn your skin a purple-grey as the silver ions accumulate in your body.
As unsightly physical afflictions go, the effects of a silver overdose are right up there with the Black Death, which has also caught the attention of scientists – though this time it’s a history lesson. The bacterium that wiped out half of Europe’s population between 1347 and 1351 is still around. However, it doesn’t seem particularly deadly to modern scientific eyes, which makes the virulence somewhat puzzling. That puzzle is about to be solved: thanks to a newly developed technique, scientists are studying the genomes of the various strains of plague bacterium. The hope is that the insights gained will warn us about which subtle changes to pathogens in our environment could lead to widespread modern-day epidemics.
Thanks to the same new technique, we also now have the complete genome sequence of a leprosy bug carried by a young Danish woman who died 700 years ago. The makeup of the medieval bacterium, published in the 14 June issue of Sciencemagazine, is remarkably similar to what we know of the make-up of modern leprosy bacteria. That means the Danish leper may well help us find new treatments.
Finally, religious studies. The writer of Ecclesiastes said there’s nothing new under the sun, and the US National Institutes of Health has decided that it’s a good piece of advice. The NIH has instigated a programme which suggests that the best way of speeding the discovery of new drugs is to repurpose the old ones. Drugs that passed safety tests but were abandoned for reasons of efficacy or profitability are being tried in previously unexplored applications. So far, the search has unearthed candidates for treating conditions such as Alzheimer’s disease, alcohol and nicotine addiction and muscular dystrophy. The drugs will now go into animal studies and clinical trials; researchers hope that some will reach the market in a few years’ time.