Stem cells found in urine show potential
Using human urine as a source of stem cells to grow body parts sounds a bit disgusting, doesn’t it? But researchers from Wake Forest University say have they’ve identified stem cells in urine that can be directed to develop into numerous types of cells. This comes a week after Chinese scientists reported that they were able to grow rudimentary teeth from urine stem cells.
The Wake Forst researchers endorsed the use of stem cells derived from urine samples, citing their potential effectiveness and relatively low cost. Stem cells can be harvested from a variety of tissues, but the procedures can be invasive, expensive or complicated. Urine-based stem cell harvesting, by comparison, is simple, easy and cheap. The scientists successfully directed stem cells from urine to become bladder-type cells, including both muscle and urothelial cells that line the bladder.
These stem cells could also be used to form bone, cartilage, fat, skeletal muscle, nerve and endothelial cells, which line blood vessels. The researchers said they see great potential of these cells to treat kidney disease, urinary incontinence and erectile dysfunction.
Stem cell therapy is seen as a key to future advances in many different fields of medicine, given that any new tissue is less likely to trigger an immune response to “intruders” developed from cells in that person’s body.
FDA defines "gluten-free"
Responding to widespread labeling of products as “gluten-free,” the U.S. Food and Drug Administration (FDA) has issued a new regulation defining just what that means. The agency now requires that any food product labeled “gluten-free” can’t have more than 20 parts per million of gluten.
The boom in “gluten-free” labeling has coincided with a far greater public awareness of celiac disease, an immune system disorder that causes the body to react when exposed to gluten, a protein found in barley, rye and oats. People with celiac disease—an estimated 3 million American have the condition–have to avoid eating foods containing gluten; otherwise the lining of the small intestine can become damaged and affect the proper absorption of vital nutrients into the bloodstream. The severity of the reaction to gluten differs from patient to patient, but the new FDA regulation is meant to protect people from even trace amounts of gluten.
While many gluten-free foods already adhere to the rule, manufacturers and distributors will have 12 months to institute it and update their labels. This rule also applies to other terminology related to gluten content, such as “free of gluten,” “without gluten” and “no gluten.”
Stimulating brain can create false memories
The idea that memories are fluid is taking on new meaning, as a recent study found that the memories of mice can be altered by turning on neurons in the brain associated with those memories and updating them with new information.
The findings, published in the journal Science, showed that a mouse can be made to fear a cage by giving it a foot shock while also reactivating a memory of the cage in order to associate the two.
For the study, scientists used a previously discovered technique to pinpoint the handful of neurons that are activated in the brains of mice in any given situation. The technique involves a method of controlling brain cells through bursts of light. Researchers engineered brain cells to produce light-sensitive proteins whenever the neurons were activated in a new setting or situation.
In this study, researchers first exposed mice to one of four unique cages with distinct flooring materials, artificial smells and lighting. As the mice discovered these surroundings, the activated neurons in their brain produced the special light-sensitive proteins. Then, the mice were moved to a second cage, where scientists turned on the neurons that had been activated in the first cage, while simultaneously shocking their feet. Then the mice were returned to the first cage, but they became clearly fearful of the setting even though they had never received a shock there.
In contrast, when the mice were put in a new third cage they showed no fear, and the control group that did receive shocks, but no neuron reactivation, were not afraid of the first cage.
Scientists hope to test their technique on memories of pleasure, memories of objects and memories of other mice.