Key scientific developments of 2013

This year featured some landmark breakthroughs in the field of medical science and technology. Here are some of the key scientific developments of 2013. A promising method to curb malaria transmission Researchers at Michigan State University engineered mosquitoes that are resistant to malaria infection. This has the potential to stop the transmission of malaria to humans. In 2010, the disease affected 219 million people and caused about 660,000 deaths. The study, published in May in Science magazine, uses a strain of the bacterium Wolbachia injected into embryos of the mosquito species Anopheles stephensi, a key malaria vector. The bacterium acts as a malaria vaccine of sorts for these mosquitoes as the malaria parasite does not cope well in Wolbachia-infected mosquitoes. Of thousands of embryos injected, one developed into a female that carried Wolbachia. The mosquito line derived from her maintained a 100 per cent Wolbachia infection frequency through all 34 generations bred during the study. Next, various ratios of Wolbachia-infected females were introduced into a non-infected mosquito population and, in each case, the entire population carried the bacteria in eight generations or less. If the Wolbachia infection spread in the wild, it could potentially stop malaria transmission. This method would be more economical than others such as using pesticides or human vaccine, which is a big advantage given most malaria endemic areas are poor. A vaccine for a common childhood disease Since its discovery in 1969, enterovirus 71 (EV71) has caused major outbreaks of hand, foot and mouth disease (HFMD) around the world, affecting mostly children. The greatest number of serious cases, potentially leading to fatal meningitis and encephalitis, occur in the region. On the mainland alone, 2.16 million cases of EV71 were reported along with 560 EV71 related fatalities in 2012. In May, scientists announced a successful randomised trial for the world's first vaccine against EV71, developed by Chinese company Sinovac Biotech. The trial was done in three sites in Jiangsu province and one in Beijing, involving 10,245 healthy infants and children aged six to 35 months, who received two doses of placebo or vaccine 28 days apart. The vaccine gave 90 per cent protection against clinical EV71-associated HFMD and 80.4 per cent against EV71-associated disease, including neurological complications, for at least 12 months. No serious adverse events were recorded. But many viruses can cause HFMD and the scientists note this vaccine only has an impact on EV71-related disease, which they say caused "only a small proportion of cases" during the year-long surveillance period. Gene sequencing technique sheds light on human development Genetic diseases could be diagnosed with better accuracy, and as early as when an embryo consists of only eight cells, thanks to a new technique called single-cell RNA sequencing. University of California Los Angeles scientists, collaborating with teams in China, used the technology to track the genetic development of a human and a mouse embryo at an unprecedented level of accuracy. They published their findings online in the journal Nature in July. The technique allows researchers to determine the precise nature of all of the genes that are actively expressed in a particular cell. It marks a major development in genetic diagnoses, which previously could not be conducted this early in embryonic development and required much larger amounts of biological material. The technology may have important uses in reproductive medicine, say the researchers. Bionic vision Sufferers of retinal pigmentosa, an incurable degenerative eye disease that can lead to blindness, have new hope with the first bionic eye to be approved by the US Food and Drug Administration (FDA). The retinal prosthetic, called Argus II, transmits images from a small, eye-glass-mounted camera wirelessly to a device implanted on a patient's damaged retina. The device sends electrical signals via the optic nerve, and the brain interprets a visual image. It may not yet fully restore sight, but has enabled patients to see basic shapes, and in some cases, to even read. The prosthetic is made by California-based Second Sight Medical Products. Product development took more than 20 years of work in the field, three clinical trials, more than US$100 million in public investment by the National Eye Institute, the Department of Energy, and the National Science Foundation, and an additional US$100 million in private investment. Artificial pancreas for diabetics Diabetics can better control their condition and in a more convenient way, with the recent approval by the FDA of a system to automatically stop insulin delivery in diabetes patients when blood-sugar levels fall too low. The first "artificial pancreas" to be approved in the US, Medtronic's MiniMed530G, can be hooked onto the belt and is connected to sensors inserted under the skin. It continuously monitors blood-glucose levels and controls the insulin dosage to maintain an optimal balance. A low blood-glucose level (hypoglycemia) causes symptoms from confusion to seizures, unconsciousness and death. A similar system is approved for use in Europe. From paralysed to walking People with lower-limb disabilities have a chance of being on their own two feet again with a "bionic" suit called ReWalk. Invented by Israeli entrepreneur and founder of Argo Medical Technologies, Dr Amit Goffer, a quadriplegic, the device is made up of a light wearable brace support, a computer-based control system and motion sensors. The sensors anticipate the shifts in the user's balance and translate them into user-initiated movements such as walking and standing, turning and going up and down stairs. Claire Lomas, 33, a paraplegic from Britain, wore the exoskeleton to complete the London Marathon in April 2012. The system comes in two versions. The rehabilitation version is available in centres in Europe, the US and Israel, while the personal version is only available for purchase by private users in Europe for now. Seizing time before a seizure There's hope yet for epileptic patients whose seizures have not responded to medication. The Response Neurostimulation System (RNS), developed by California-based company NeuroPace, is an implantable therapeutic device designed to detect abnormal electrical activity in the brain and respond by delivering imperceptible electrical stimulation to normalise brain activity and prevent a seizure. It's the world's only RNS approved for clinical use. Two weeks ago, the University of Southern California's Keck School of Medicine was the world's first medical centre to implant the device, which recently gained FDA approval, in a 28-year-old woman diagnosed with epilepsy in 2004. "Implanting [this device] is probably safer than traditional epilepsy surgery because we're not taking anything out," says Dr Charles Liu, professor of neurosurgery and neurology at USC. FDA approval of the RNS device came after a randomised clinical trial of 191 patients with drug-resistant epilepsy across 32 clinical sites. The study showed that, by three months after the device was turned on, patients experienced a nearly 38 per cent reduction in monthly seizures, compared to 17 per cent among patients who had the implant turned off. Two years post-implant, 55 per cent of patients experienced a 50 per cent or greater reduction in seizures. No more needle-phobia Fear needles? No problem. Soon, all you have to do is stick on a fingertip-sized patch on your skin as a pain-free alternative to the typical vaccine needle injection. Invented by biomedical engineer Mark Kendall, a professor at the University of Queensland in Australia, the Nanopatch is covered in thousands of vaccine-coated microscopic spikes that deposit vaccinations under the skin's surface. It has had impressive results in animal tests, and human trials are under way. Tests have shown it can generate the same immune response with only a fraction of the dose needed in a conventional vaccine. So it costs much less to produce. It also uses the vaccine in dried form, so it does not need trained staff to deliver it. life@scmp.com

Key scientific developments of 2013

.css-1c6uqr6{color:inherit;font-weight:inherit;font-size:inherit;font-family:inherit;line-height:inherit;overflow-wrap:break-word;}Medical breakthroughs this year included a new method to curb the spread of malaria and a bionic eye. David Tan assesses the important scientific developments of 2013

Medical breakthroughs this year included a new method to curb the spread of malaria and a bionic eye. David Tan assesses the important scientific developments of 2013