CHARLESTON, South Carolina – The Medical University of South Carolina congratulates Dr. Joseph A. Helpern and his co-authors from New York University (NYU) School of Medicine for their recent publication in the prestigious peer reviewed international scientific journal, Nature Physics (published on-line, March 6, 2011, DOI: 10.1038/nphys1936). The paper describes a new mathematical relationship between biological membrane permeability and how it affects the movement (diffusion) of water or other molecules that has gone unknown for over 70 years. Dr. Helpern states that “knowledge about biological (cell) membrane permeability can help us understand how biological tissues function, when they are healthy, and more importantly when they are not, like in diseases such as cancer, stroke and multiple sclerosis, etc.” It is thought that this new discovery will provide a powerful new approach to studying diseases. The research for his publication began at NYU School of Medicine prior to Dr. Helpern recently joining the faculty at MUSC as Vice Chairman for Radiology Research, CoEE Endowed Chair in Brain Imaging and Director of the new Center for Biomedical Imaging.
Dr. Helpern explained the significance of this work in a recent interview. “Membranes exist in most every material. To function properly, biological tissues (cells) depend heavily on the properties of membranes. Membrane-like barriers also exist in other materials like porous media (e.g. oil shale, ceramics, cement) where their properties can be important for oil retention and material strength. One of the most fundamental properties of any membrane is its permeability (leakiness) to liquid substances like water. As a water molecule randomly moves around (“diffusion”) and bumps into a membrane, sometimes it passes through and sometimes it does not. Whether or not is does depends on the membrane permeability.”
For many years, no one had been able to figure out how to measure membrane permeability without disturbing or destroying the biological tissue (living organism) or porous media. “Since diffusion of molecules can be probed by either by passing an electric current through the sample or by using magnetic resonance imaging (MRI), this new result makes possible, for the first time, the non-invasive measurement of membrane permeability” states Dr. Helpern. The mathematical relationship described in his paper is derived by borrowing advanced theoretical techniques from an area of science called condensed matter physics.
The paper is an example of Dr. Helpern’s research in understanding the basic biophysics of tissue, particularly in neurological diseases. He and his co-workers are developing non-invasive imaging methods that will someday be used to diagnose diseases such as Alzheimer’s Disease (AD), Attention-Deficit Hyperactivity Disorder (ADHD), cancer and stroke.
The paper in Nature Physics was published in advance on line on March 6, 2011. Papers published online before they have been allocated to a print issue are citable via a digital object identifier (DOI) number. The DOI for this paper is 10.1038/nphys1936. Once the paper is published electronically, the DOI can be used to retrieve the abstract and full text (abstracts are available to everyone, full text only to subscribers) by going to http://dx.doi.org/10.1038/nphys1936.
Read Nature Physics article