We attempt to understand fundamental relationships between function and structure in living tissues, “engineered” tissue constructs, and tissue analogs. Specifically, we are interested in how microstructure, hierarchical organization, composition, and material properties affect the biological function and dysfunction of tissues. We investigate biological and physical model systems at different time and length scales, making physical measurements in tandem with mathematical and computational models we use to design these experiments and interpret their findings. Primarily, we use water molecules to probe both equilibrium and dynamic interactions among tissue constituents over a wide range of time and length scales. At macroscopic length scales, to determine the equilibrium osmo-mechanical properties of well-defined model systems, we vary water content or ionic composition. To probe tissue microstructure and microdynamics, we employ atomic force microscopy (AFM), small-angle X-ray scattering (SAXS), small-angle neutron scattering (SANS), static light scattering (SLS), dynamic light scattering (DLS), and nuclear magnetic resonance (NMR) relaxometry and diffusometry. We also develop and use physics and engineering principles to help us understand how observed changes in tissue microstructure and physical properties affect transport of mass, charge, and momentum. The most direct noninvasive in vivo method for characterizing these essential transport processes in tissues is via magnetic resonance imaging (MRI), which we use to follow microstructural changes in development, degeneration, aging, and trauma. A goal of our basic tissue sciences research is to translate our quantitative methodologies and the understanding we glean from them from "bench to bedside."
Our tissue sciences activities dovetail with our basic and applied research in quantitative imaging, which is intended to generate measurements and maps of intrinsic physical quantities, including diffusivities, relaxivities, or exchange rates, rather than the qualitative images used in radiology. Our quantitative imaging group uses knowledge of physics, engineering, applied mathematics, imaging and computer sciences, and insights gleaned from our tissue sciences research to discover and develop novel imaging biomarkers that sensitively and specifically can detect changes in tissue composition, microstructure, or microdynamics. Our ultimate goal is to use these biomarkers to assess normal and abnormal development, diagnose childhood diseases and disorders, and characterize degeneration and trauma. Primarily, we use MRI as our imaging method of choice because it is well suited to many NICHD–mission critical applications: it is non-invasive, non-ionizing, generally requires no exogenous contrast agents or dyes, and is deemed safe for use with pregnant mothers and their fetuses, and children in both a clinical and a research setting.
One of our technical objectives has been to make clinical MRI scanners quantitative scientific instruments capable of producing reproducible, accurate and precise imaging data and to be able to measure and map useful imaging quantities for pre-clinical and clinical applications, including for single scans, longitudinal and multi-center studies, for personalized medicine, and for populating imaging databases with high-quality normative data.
BRAIN Initiative: Bridging Gaps in Neuro Knowledge (NIH Catalyst, Volume 25 Issue 6, November–December 2017)
"Measuring the latency connectome" (34:00) – Plenary talk, 2017 NIH Research Festival (September 13, 2017)
"The Invention and Development of Diffusion Tensor NMR and MRI at the NIH" (YouTube), recorded at a conference hosted by Cardiff University Brain Research Imaging Centre (CUBRIC), January 31 – February 1, 2017
Dr. Derek Jones, Former NIH Mentee, Directs Brain Imaging Center in Wales (NIH Record, July 1, 2016)
"Twitchy Nerves (Literally) May Explain Epilepsy, Pain" on NPR's Morning Edition (October 5, 2010)
- Dr. Ruiliang Bai receives the Summa Cum Laude Merit Award at ISMRM 2017.
- Dr. Ruiliang Bai receives two Summa Cum Laude awards for outstanding posters at ISMRM 2016
- Dr. Ruiliang Bai receives the Young Investigator Award at the Overseas Chinese Society for Magnetic Resonance in Medicine
- Dr. Dan Benjamini receives the 2016 Giulio Cesare Borgia Prize at MRPM13
Smith, C. (2002) NIH commercializes new imaging technique. Nature Medicine 8(9): 906.