It’s a common problem in medicine: getting a drug to go just where it’s needed in the body in order to minimize the dosage, maximize the benefit, and avoid side effects as much as possible. Three new developments show promise in making this easier. Dr. Hanadi Sleiman and his team at the McGill University Chemistry Department have invented a new method for using DNA to create nanotubes of any shape that can encapsulate drugs or other cargo. The nanotubes can be porous or closed and then, by the addition of a specific DNA strand, triggered to open and release their contents.
Bacteria (and other microorganisms) often adhere to surfaces and form tough, self-protective biofilms. Existing antibiotics often have difficulty penetrating them, especially in the case of antibiotic-resistant bacteria such as MRSA. Dr. Christian Melander and his team at North Carolina State University have discovered an effective new weapon for the fight. By pretreating the bacteria with a 2-aminoimidazole compound, penicillin became 128 times more effective, even against penicillin-resistant bacteria. Biofilm dispersal was 1,000 times more effective.
Magnets have been in the bags of quacks for generations, but sometimes real doctors find a good use for them. Ke Cheng, Tao-Sheng Li, Konstantinos Malliaras, Darryl Davis, Yiqiang Zhang, and Eduardo Marbán of Cedars-Sinai Medical Center in Los Angeles are using magnets to improve stem cell therapy for heart disease. Normally many of the injected cells are washed away by blood flow and don’t make it to (or stay in) the area of the heart where they are needed. Their solution: load the stem cells with tiny iron particles, then place a toy magnet externally, close to the damaged part of the heart. Experiments with rats showed that three times as many cells stayed in the heart, and healing improved.