Australian researchers say they are ready to begin testing a promising new treatment for Alzheimer’s disease. The technique, which involves guided ultrasound, could hold out hope for the 44 million people worldwide who suffer from the progressive brain disorder.

Scientists are unsure what causes Alzheimer’s, but they know it involves plaques that form when abnormal amounts of beta-amyloid protein clump together and collect between brain cells. Developing a treatment is difficult because the blood-brain barrier, which protects the brain from infections and toxins, also keeps out many drugs. Also, Alzheimer’s impairs microglial cells in the brain that usually clean up harmful proteins, and the blood-brain barrier blocks components of the immune system that could stimulate the cells back into action.

In 2015 University of Queensland scientists discovered that guided ultrasound could open spots on the blood-brain barrier of mice with Alzheimer’s. The researchers injected harmless microbubbles of air into the bloodstream of the mice, then used MRI to guide ultrasound waves to specific regions of the barrier. The sound waves caused the microbubbles to vibrate and enlarge, temporarily opening up the targeted areas. The procedure cleared almost all of the plaque from 75 percent of the mice, whose memory subsequently improved, the website IFLScience reported.

Another study, published July 25 last year in Nature, tested the safety of the method in five human patients with early to moderate Alzheimer’s. In all five patients the researchers safely opened the blood-brain barrier for less than 24 hours without the use of drugs. The procedure allowed the body’s own natural antibodies to cross the barrier and stimulate glial cells to clean out plaques. The researchers also discovered that the focused ultrasound increased the number of new brain cells in the hippocampus, a brain region involved in learning and memory.

In December the University of Queensland announced that researchers had received Australian funding to test the effectiveness of this approach and planned to begin human trials later this year.

Building better plastics

Researchers at Tel Aviv University recently designed a bioplastic polymer produced by microorganisms feeding on seaweed. The biodegradable plastic produces no toxins and could offer one possible solution to the plastic pollution threatening the world’s oceans.

Plastic is a worrisome pollutant because it takes hundreds of years to decay, and its petroleum-based production process releases chemical contaminants. Bioplastics don’t use petroleum and degrade quickly, but growing the necessary plants or bacteria to make them requires fertile soil and fresh water, scarce commodities in some countries.

The new technique, described in January in Bioresource Technology, produces a biodegradable plastic that does not require soil or fresh water. “The process we propose will enable countries with a shortage of fresh water, such as Israel, China and India, to switch from petroleum-derived plastics to biodegradable plastics,” Tel Aviv University researcher Alexander Golberg said in a statement. —J.B.

Assigned allergy

A lung transplant recipient recently received more from her organ donor than just a lung: She also acquired his peanut allergy. After receiving a lung from a 22-year-old male donor with a peanut allergy, the 68-year-old woman suffered a severe allergic reaction to a peanut butter sandwich.

Although the case, described in August in Transplantation Proceedings, represents a rare phenomenon, other studies have documented transplant recipients acquiring food allergies following liver, kidney, lung, bone marrow, heart, and kidney transplants, according to Live Science. —J.B.