Teaching rats to drive
Painkillers for depression
Taking aspirin or ibuprofen every day can help relieve the symptoms of depression, a new study has found. Researchers in China looked at 30 previous studies examining the impact of anti-inflammatory drugs on patients who’d suffered major depressive disorders. They considered not only non-steroidal anti-inflammatory drugs (NSAIDs) – a class that includes many over-the-counter painkillers – but also others with anti-inflammatory properties, such as statins. The NSAIDs appeared to make the most difference: taking a 400mg daily dose appeared to be 79% more effective than a placebo at eliminating depressive symptoms, and 52% more effective at reducing their overall severity. But most of the other treatments seemed to have a positive impact, and also appeared to boost the effectiveness of anti-depressants when taken at the same time. While depression isn’t regarded as an inflammatory disorder, several recent studies have linked it to brain and body inflammation, leading to speculation that an overactive immune system (which causes inflammation) could be a factor in the condition. “Depression may simply be the price we pay for having an immune system,” said Prof Alan Carson of the University of Edinburgh, who edited the team’s findings in the Journal of Neurology, Neurosurgery & Psychiatry.
Pain is worse on damp days
People with arthritis have long reported that their pain gets worse in winter. Now a study has confirmed that damp weather does indeed appear to exacerbate chronic pain in patients with a variety of long-term conditions. However, the cold doesn’t seem to make any difference. A team at the University of Manchester recruited more than 13,000 people with arthritis, fibromyalgia, migraine and neuropathic pain from across the UK, and asked them to use their smartphones to keep a daily record of their symptoms. When they compared this data with local weather reports, they found that participants were most likely to report worse-than-average pain on humid days. Low atmospheric pressure and high wind speed were also associated with more pain, to a lesser extent; but lower temperatures alone made no difference, and nor did rainfall. Prof Will Dixon, who led the study, said that if scientists could find out more about the relationship between humidity and pain, it might “open the door to new treatments”.
Is Botswana our true homeland?
A vast wetland south of the Zambezi River in what is now Botswana has been identified as the “cradle of humankind” – the place where Homo sapiens first originated some 200,000 years ago. According to a team in Australia, the ancestors of modern humans thrived in this area, which was a green oasis surrounded by desert, for around 70,000 years. At that point, climate change brought rains to the northeast and southwest that created new lush corridors away from their homeland, allowing them to migrate, first to other parts of Africa, and then across the globe. The study, published in the journal Nature, involved the analysis of mitochondrial DNA (which passes unchanged down the maternal line) from present day Khoisan people, in South Africa and Namibia. Click speakers, they are known to have the most diverse mitogenomes of any people on Earth, which suggests that their DNA most closely resembles that of our ancestors at the base of the human family tree. By comparing this data with existing genetic data from other populations, the team pinpointed the area around the Makgadikgadi Pan in northern Botswana as the most likely site of humanity’s “founding community”. However, other experts were sceptical about the findings. “I’m definitely cautious about using modern genetic distributions to infer exactly where ancestral populations were living 200,000 years ago, particularly in a continent as large and complex as Africa,” said Prof Chris Stringer of London’s Natural History Museum.
Medical file
An Italian meta-study has found “no evidence” for the commonly held view that sex in late pregnancy will hasten the baby’s arrival, reports the New Scientist. On the plus side, the scientists also found that there appeared to be “no detrimental effect of having sex at term”.