In 1991, at a conference sponsored by a fragrance company called the Erox Corporation, two University of Utah scientists presented research on a tantalizing pair of chemical compounds provided by the company. They reported that in a few dozen human volunteers, the molecules androstadienone and estratetraenol activated the vomeronasal organ (VNO)—an olfactory organ that senses pheromones in many animals—in a sex-specific manner. The company patented these molecules as putative human pheromones. Continue reading “What Will It Take To Find a Human Pheromone?”
Earlier this year, while reporting a story about the bugs in the bees — that is, the microbiome in bees’ guts — I spoke to a USDA researcher named Jay Evans, who described some work in his lab testing whether feeding bees probiotics can help protect against pathogens that weaken hive health. Continue reading “Probiotics for honeybees”
The antibiotic discovery pipeline received a much-needed boost in January. Teixobactin, a natural product from previously uncultured bacteria, was shown to have potent activity against Gram-positive pathogens and a novel mechanism of action, making it a potentially valuable asset in the battle against bacterial resistance. Continue reading “New twist on antibiotic hunt hits pay dirt”
Male, but not female, experimenters induce intense stress in rodents that can dampen pain responses, according to a paper published today in Nature Methods. Such reactions affect the rodents’ behaviour and potentially confound the results of animal studies, the study suggests.
The authors discovered this surprising gender disparity while investigating whether the presence of experimenters affects rodent pain studies. For years, anecdotal reports have suggested that rodents show a diminished pain response when a handler remains in the room.
For several decades, attention had focused on the idea that the disease was caused by elevated dopamine levels in the brain, particularly in the striatum, a nugget of brain tissue nestled under the cortex. But by the 1990s, the dopamine hypothesis was proving inadequate to fully explain the disease. In vivo imaging with computed tomography and magnetic resonance imaging, and data from post-mortem studies in people with schizophrenia, pointed to cortical effects and implicated other neurotransmitter systems, such as glutamate and serotonin. Biologists were also learning to create transgenic mouse models of the disease, providing a set of tools with which to investigate genetic and aetiological factors.
A new database pools health registry data from seven countries, dramatically boosting sample sizes for epidemiological studies of autism. The virtual tool, built by an international consortium of researchers, allows them to effectively compare data across populations.
“This is a first for autism,” says Diana Schendel, professor of psychiatric epidemiology at Aarhus University in Denmark, who spearheaded the project.
One of the most, if not the most, contentious issues in science is the use of animals in research. Scientists experiment on animals for a host of different reasons, including basic research to explore how organisms function, investigating potential treatments for human disease, and safety and quality control testing of drugs, devices and other products. Its proponents point to the long list of medical advances made possible with the help of animal research. Opponents believe it is cruel and meaningless, as observations in animals often do not translate directly to humans.
[Read more at BBC Future // June 10, 2013]
Nearly two years ago, the US government office that oversees human research ethics launched the first-ever major revision to the so-called Common Rule, the 22-year-old regulation that governs the protection of human research subjects there. But the process set into motion by that agency—the Office of Human Research Protections (OHRP), a division of the US Department of Health and Human Services (HHS)—is dragging on. And a vocal contingent of bioethicists and researchers say the changes on the table are not enough to fix an outdated and overburdened system, advocating instead for a more fundamental rethink.
It all started with an expression problem. Michael Gottesman and his lab members at the US National Cancer Institute in Bethesda, Maryland were studying a membrane protein involved in drug metabolism called P-glycoprotein to understand why some people develop resistance to chemotherapy during cancer treatment. But when the scientists tried to express large quantities of the protein in bacterial cells, they hit a wall.
“It was a real mess,” Gottesman recalls. “We couldn’t do it.”
The genetic code is read in triplets called codons, 64 of them representing just 20 amino acids. That means there is more than one codon for each amino acid, and different organisms preferentially use certain codons to make translation faster.
Peggy Willocks was 44 when she was diagnosed with Parkinson’s disease. It progressed quickly, forcing her to retire four years later from her job as a primary-school principal in Elizabethton, Tennessee. Soon, her condition had deteriorated so much that she was often unable to dress and feed herself, take care of basic hygiene or walk unaided across a room.
Willocks enrolled in a trial for an experimental therapy called Spheramine, developed by Titan Pharmaceuticals, a biotechnology company in South San Francisco, California. Spheramine consists of cultured human retinal epithelial cells bound to specialized man-made carrier molecules. The cells are implanted into the brain, where it is hoped that they will produce the dopamine precursor levodopa, which can reduce the symptoms of Parkinson’s disease. In August 2000, Willocks became the second person ever to receive the treatment. After having a steel halo — a stereotactic frame — bolted to her skull, she was put under general anaesthesia. Surgeons then used the frame and coordinates obtained from numerous magnetic resonance imaging (MRI) scans to pinpoint the location at which to drill. They then snaked a catheter through her brain’s white matter to deliver the cells into the striatum.
At first there was no effect, but Willocks says that after 6–8 months she began to feel better. The changes were always moderate and gradual, except for once, about nine months after her surgery, when she showed what her doctor called a “radical” improvement in balance. By a year after the treatment, she and the five other patients in the phase I trial showed an improvement in motor ability of 48%, and those gains largely held 4 years later.
Ten years on, she says she notices her condition worsening, but is still doing much better than she was before her operation. She has no doubt that the treatment works. Investigators disagree…