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Genetic makeup of organisms varies wildly
Researchers from Edith Cowan University (ECU) in WA have been part of an international study, published in Nature, which found that the genetic composition of trillions of tiny organisms living on and in our bodies can be incredibly different from person to person and country to country. The research was co-authored by ECU PhD candidate Aaron Jenkins and compared the genetics of the human microbiome from populations in the United States and in Fiji. The researchers found that the composition of new genes that bacteria can acquire from neighbouring bacteria – known as mobile genes – differs depending on their environment. These mobile genes can confer upon other bacteria antibiotic resistance or the ability to break down sugars or starches from food better than other populations. What this means in the big picture is that the kind of diet that people have or the medicines they take could change the ability of the microbiome in the body to perform in the body’s favour. Antibiotic usage could also potentially be tailored to specific regions to minimise likelihood of encountering or fostering resistance.
Scientists calling for experiments on ecstasy
US researchers have called for a rigorous scientific exploration of how the effects of methylenedioxymethamphetamine (MDMA), commonly known as ecstasy, to precisely identify how the drug works, with a view to developing therapeutic compounds. In a commentary published in Cell, Robert Malenka, a psychiatrist and neuroscientist at Stanford University wrote: “We’ve learned a lot about the nervous system from understanding how drugs work in the brain – both therapeutic and illicit drugs. If we start understanding MDMA’s molecular targets better, and the biotech and pharmaceutical industries pay attention, it may lead to the development of drugs that maintain the potential therapeutic effects for disorders like autism or PTSD but have less abuse liability.” MDMA is described as an “empathogen”, a compound that promotes feelings of empathy and close positive social feelings in users. Researchers still don’t know exactly how MDMA works in humans, what regions of the brain it targets, or all of the molecular pathways it affects. Malenka and colleagues wrote that scientific study to uncover its mechanisms could help explain fundamental workings of the human nervous system, including how and why we experience empathy. Early clinical cases and a small trial in 2013 also showed some use for MDMA as a treatment during therapy for patients with PTSD, possibly aiding patients in forming a stronger bond with a therapist.
New technique shows Alzheimer proteins in 3D
US researchers have developed a new technique to make tissue transparent, like glass, enabling them to look through the brains of deceased Alzheimer patients and examine the structure of the sticky clumps of toxic protein that may be involved in the disease, known as beta-amyloid plaques. The technique, called iDISCO, involves soaking the brains in a solution that gives the fats in the brain an electrical charge. The brain is then exposed to the opposite electric charge, and like a magnet, it forces all the fat from the brain, leaving a hard, transparent, 3D structure behind. The researchers say this work may help researchers better understand these plaques, and their relationship with Alzheimer disease in general. The findings appear in Cell Reports. “Until now, we’ve been studying the brain using 2D slices; and I’ve always felt that was inadequate, because it’s a complex 3D structure with many interlocking components,” says senior author Marc Flajolet, an assistant professor in the Laboratory of Molecular and Cellular Neuroscience at The Rockefeller University. “Not only was slicing time-consuming and 3D reconstruction laborious when not erroneous, it gave us a limited view. We needed some way to look at this 3D structure in all of its dimensions without preliminary slicing of the brain.”