Muscle force development after low-frequency magnetic burst stimulation in dogs.

INTRODUCTION: Magnetic stimulation allows for painless and non-invasive extrinsic motor nerve stimulation. Despite several advantages, the limited coupling to the target reduces the application of magnetic pulses in rehabilitation. According to experience with electrical stimulation, magnetic bursts could remove this constraint. METHODS: A novel burst stimulator was used to apply single and burst pulses to the femoral nerve in 10 adult dogs. A figure-of-eight coil was connected, and pulses were applied at 7.5 HZ. Contractions of the quadriceps muscle were measured via an angle force transducer. RESULTS: Muscle forces were significantly higher upon burst stimulation than after single pulses. Four consecutive burst pulses proved most effective. Stimulation by more bursts resulted in fatigue. CONCLUSION: Burst stimulation is superior to standard magnetic single pulses, and 4 consecutive burst pulses proved most effective.

Targeted delivery of magnetic aerosol droplets to the lung.

The inhalation of medical aerosols is widely used for the treatment of lung disorders such as asthma, chronic obstructive pulmonary disease, cystic fibrosis, respiratory infection and, more recently, lung cancer. Targeted aerosol delivery to the affected lung tissue may improve therapeutic efficiency and minimize unwanted side effects. Despite enormous progress in optimizing aerosol delivery to the lung, targeted aerosol delivery to specific lung regions other than the airways or the lung periphery has not been adequately achieved to date. Here, we show theoretically by computer-aided simulation, and for the first time experimentally in mice, that targeted aerosol delivery to the lung can be achieved with aerosol droplets comprising superparamagnetic iron oxide nanoparticles--so-called nanomagnetosols--in combination with a target-directed magnetic gradient field. We suggest that nanomagnetosols may be useful for treating localized lung disease, by targeting foci of bacterial infection or tumour nodules.