Scientists in Germany used stem cells to repair damaged visual neurons in adult mice, their colleagues in China and England adapted a portion of the human gut to build a long-lasting battery, and a team at Harvard University 3D printed a heart on a chip. Who says that biology is boring!
Scientists at Cambridge University in England and the Beijing Institute of Technology have built a new kind of battery inspired by the human gut. They say a commercial version of the design would have five times the energy density of the batteries currently powering our electronics. Unlike those batteries, which use lithium ions to store energy, the new technology uses a thin layer of lithium-sulphur covered with a shag rug of tiny zinc oxide wires that resemble villi, the tiny prongs that line the small intestine and help us absorb and digest nutrients. These structures trap pieces of the active material when they flake off so they can be reused. “It’s a tiny thing, this layer, but it’s important,” said study co-author Paul Coxon of Cambridge’s Department of Materials Science and Metallurgy. “This gets us a long way through the bottleneck which is preventing the development of better batteries.” Researchers have known that the combination of lithium and sulphur could store more energy, but the material also degraded quickly. “This is the first time a chemically functional layer with a well-organized nano-architecture has been proposed to trap and reuse the dissolved active materials during battery charging and discharging,” said the study’s lead author, Teng Zhao of Cambridge. The results were published in the journal Advanced Functional Materials.
Researchers in Germany have used transplanted embryonic stem cells to replace damaged neurons in the visual cortex of adult mice and restore their function. “Transplanted embryonic nerve cells can indeed be incorporated into an existing network and correctly carry out the tasks of damaged cells originally found in that region,” the team wrote in a news release. They say the research could help find new treatment for neurodegenerative diseases such as Parkinson’s and Alzheimer’s. The scientists said they were “able to show that the new cells formed the synaptic connections that neurons in their position in the network would normally make, and that they responded to visual stimuli.” The team is working at the Max Planck Institute of Neurobiology in Munich, the Ludwig Maximilian University of Munich and Helmholtz Zentrum München.
A few weeks ago, we told you about a disabled patient who could control a robotic arm with his mind and feel its fingers. Closer to home, a team of American neuroscientists and engineers in the U.S. have developed a prosthetic arm that allows amputees “to feel the same intensity of pressure on their prosthetic hands as they feel with their intact hands.” The team equipped the prosthesis with pressure sensors that transmit signals to a portable stimulator. This device then sends electrical pulses to working nerves in the arm. Igor Spetic of Ohio used the system to operate a lathe. “I could feel the handle with the prosthetic hand and, instead of watching the hand, I watched the part — as you’re supposed to,” he said. The research was done at Case Western Reserve University, the Louis R. Stokes Cleveland VA Medical Center and the University of Chicago.
Researchers at Harvard University say they have developed six inks that allowed them to make “the first entirely 3D-printed organ-on-a-chip with integrated sensing.” They say that 3D printing “may one day allow researchers to rapidly design organs-on-chips … that match the properties of a specific disease or even an individual patient’s cells.” To be sure, the heart cannot be used for transplants. However, scientists can use these artificial organs for medical studies instead of those from animals. The team already used the device to conduct drug and cardiac tissue studies. “Our approach was to address these two challenges simultaneously via digital manufacturing,” said Travis Busbee, co-author of the paper and a graduate student in Harvard’s Lewis Lab. “By developing new printable inks for multi-material 3D printing, we were able to automate the fabrication process while increasing the complexity of the devices.” The results were published in the journal Nature Materials.
Media outlets around the world ran stories about scientific detective work that allowed researchers led by Cambridge University historian Richard McKay and evolutionary biologist Michael Worobey at the University of Arizona in Tucson to debunk the myth that French-Canadian flight attendant Gaétan Dugas was the Patient Zero who started the AIDS epidemic in the U.S. in the early 1980s. The journal Nature reported that analysis of “decades-old” blood serum samples showed that “the virus had been circulating in North America since at least 1970, and that the disease arrived on the continent through the Caribbean from Africa.” The samples came from gay men who suffered a type of skin cancer called Kaposi’s sarcoma. The researchers believed the sarcoma was tied to the HIV infection, which also causes AIDS. Dugas died in 1984.