School of Health Sciences - Research in Radiological Health (Health Physics, Medical Physics and Radiation Biology)

Dr. Ulrike Dydak, Ph.D., Assistant Professor of Health Sciences. Dr. Dydak's research interest is in the area of in vivo magnetic resonance imaging and focuses on the investigation of human in vivo metabolism by means of magnetic resonance spectroscopy (MRS). She has expertise in the development of new MRS pulse sequences as well as in the design and implementation of clinical MRI/MRS studies. Her former and current research interests include the development of fast spectroscopic imaging (MRSI) techniques, whole brain and high-resolution MRSI, quality assessment and quantification of MRS for clinical studies, multi-nuclear spectroscopy (1H, 31P, 13C, 23Na), high field MRS at 3 and 7 Tesla, the optimization of MRS for different body parts (prostate, breast, liver, muscle), metabolism in neurological and psychiatric disorders as well as in cancer, the development and maintenance of an in vivo spectroscopy database and the optimization and enhancement of a comprehensive visualization and processing tool for MRS in clinical research. An important aspect in all of her research is the transfer of new techniques into clinical practice and the training and education of medical professionals (e.g. radiologists) in new available techniques by offering MR spectroscopy courses.

Dr. Jian Jian Li's group is studying the biological response to radiation, especially the molecular mechanism underlying cancer treatment by radiation and protection of normal cells from radiation-induced injury and cancer risk. Current projects are focusing the role of radiation-induced gene expression pattern and signaling network that may decide the fate of an irradiated cells. Radiation-induced specific signaling pathways, e.g., transcription factor NF-κB, mitochondrial antioxidant MnSOD and cell cycle regulators, have been linked with an enhanced cell survival under radiation treatment. Small molecules or drug compounds that inhibit the radiation-induced proteins are tested to find an efficient way to increase cancer cure rate by radiation treatment. Similar signaling pathways are studied with irradiated normal cells, mouse and human tissue to determine if regulation of such radiation-induced proteins or key signaling elements can protect normal cells from radiation-induced injury and thus reduce radiation-associated cancer risk.

Dr. Shuang Liu's research interests include receptor-based target radiopharmaceuticals, new bifunctional chelators, development of new techniques for the radiolabeling of small biomolecules, formulation development, design/synthesis/evaluation of metal complexes as MRI contrast agents for cardiac perfusion imaging, and fundamental coordination chemistry of metallopharmaceuticals. Specific projects include the design, synthesis, and biological evaluation of radiolabeled receptor ligands that bind to receptors expressed on the surface of tumor cells, the development of new bifunctional chelators and new radiolabeling techniques, and the design, synthesis, and biological evaluation of paramagnetic metal (such as Gd³⁺, Mn²⁺ and Fe³⁺) chelates as MRI contrast agents.

Dr. James F. Schweitzer has primary interests in applied health physics topics, emergency response, and training. The Radiological and Environmental Management (REM) group serves as a site for formal undergraduate health physics internships where students receive an overview of the radiation safety program. Graduate students also utilize REM as a practicum site to gain experience in specialized applied health physics areas.

Dr. Robert Stewart has expertise in dosimetry, microdosimetry and computational radiation biology. The ultimate goal of his research program is to develop a multi-scale system of physical, chemical and biological models to predict the responses of cells and tissues to ionizing radiation. The system of models will be used to help guide the optimization of radiation therapy for the treatment of cancer (i.e., biologically guided radiation therapy) and to better understand and predict the human health effects of low doses of ionizing radiation. Much of his initial research has focused on developing Monte Carlo models for the induction and repair of clustered DNA lesions and on investigating the putative mechanisms underlying intrinsic radiation sensitivity, including the effects of intercellular signaling on cell death and neoplastic transformation. For additional information about his research interests, please see http://rh.healthsciences.purdue.edu/faculty/rds.html.