The Penet lab is within the Division of Cancer Imaging Research in the Department of Radiology and Radiological Science. The lab research focuses on using multimodal imaging techniques to better understand the microenvironment and improve cancer early detection, especially in ovarian cancer. By combining MRI, MRS and optical imaging, we are studying the tumor microenvironment to understand the role of hypoxia, tumor vascularization, macromolecular transport and tumor metabolism in tumor progression, metastasis and ascites formation in orthotopic models of cancer. We also are studying the role of tumor-associated macrophages in tumor progression.

The Brain Health Program is a multidisciplinary team of faculty from the departments of neurology, psychiatry, epidemiology, and radiology lead by Leah Rubin and Jennifer Coughlin. In the hope of revealing new directions for therapies, the group studies molecular biomarkers identified from tissue and brain imaging that are associated with memory problems related to HIV infection, aging, dementia, mental illness and traumatic brain injury. The team seeks to advance policies and practices to optimize brain health in vulnerable populations while destigmatizing these brain disorders. Current and future projects include research on: the roles of the stress response, glucocorticoids, and inflammation in conditions that affect memory and the related factors that make people protected or or vulnerable to memory decline; new mobile apps that use iPads to improve our detection of memory deficits; clinical trials looking at short-term effects of low dose hydrocortisone and randomized to 28 days of treatment; imaging brain injury and repair in NFL players to guide players and the game; and the role of inflammation in memory deterioration in healthy aging, patients with HIV, and other neurodegenerative conditions.

The Pathak lab is within the Division of Cancer Imaging Research in the Department of Radiology and Radiological Science. We develop novel imaging methods, computational models and visualization tools to ‘make visible’ critical aspects of cancer, stroke and neurobiology. Our research broadly encompasses the following areas: Functional and Molecular Imaging; Clinical Biomarker Development; Image-based Systems Biology and Visualization and Computational Tools. We are dedicated to mentoring the next generation of imagers, biomedical engineers and visualizers. Additional information can be found at www.pathaklab.org or by emailing Dr. Pathak.

Epilepsy affects 1-3% of the population and can have a profound impact on general health, employment and quality of life. Medial temporal lobe epilepsy (MTLE) develops in some patients following head injury or repeated febrile seizures. Those affected may first suffer spontaneous seizures many years after the initial insult, indicating that the neural circuit undergoes a slow pathologic remodeling over the interim. There are currently no methods of preventing the development of MTLE. It is our goal to better understand the process in order to slow, halt, and ultimately reverse it. Our laboratory draws on electrophysiology, molecular biology, and morphology to study the contribution of dysregulated neurogenesis and newborn neuron connectivity to the development of MTLE. We build on basic research in stem cell biology, hippocampal development, and synaptic plasticity. We work closely with colleagues in the Institute for Cell Engineering, Neurology, Neurosurgery, Biomedical Engineering, and Radiology. As physician neuropathologists our grounding is in tissue alterations underlying human neurologic disease; using human iPSC-derived neurons and surgical specimens we focus on the pathophysiological processes as they occur in patients. By understanding changes in cell populations and morphologies that affect the circuit, and identifying pathologic alterations in gene expression that lead to the cell-level abnormalities, we hope to find treatment targets that can prevent the remodeling and break the feedback loop of abnormal activity > circuit change > abnormal activity.

The Cardiology Bioengineering Laboratory, located in the Johns Hopkins Hospital, focuses on the applications of advanced imaging techniques for arrhythmia management. The primary limitation of current fluoroscopy-guided techniques for ablation of cardiac arrhythmia is the inability to visualize soft tissues and 3-dimensional anatomic relationships. Implementation of alternative advanced modalities has the potential to improve complex ablation procedures by guiding catheter placement, visualizing abnormal scar tissue, reducing procedural time devoted to mapping, and eliminating patient and operator exposure to radiation. Active projects include • Physiological differences between isolated hearts in ventricular fibrillation and pulseless electrical activity • Successful ablation sites in ischemic ventricular tachycardia in a porcine model and the correlation to magnetic resonance imaging (MRI) • MRI-guided radiofrequency ablation of canine atrial fibrillation, and diagnosis and intervention for arrhythmias • Physiological and metabolic effects of interruptions in chest compressions during cardiopulmonary resuscitation Henry Halperin, MD, is co-director of the Johns Hopkins Imaging Institute of Excellence and a professor of medicine, radiology and biomedical engineering. Menekhem M. Zviman, PhD is the laboratory manager.

The Artemov lab is within the Division of Cancer Imaging Research in the Department of Radiology and Radiological Science. The lab focuses on 1) Use of advanced dynamic contrast enhanced-MRI and activated dual-contrast MRI to perform image-guided combination therapy of triple negative breast cancer and to assess therapeutic response. 2) Development of noninvasive MR markers of cell viability based on a dual-contrast technique that enables simultaneous tracking and monitoring of viability of transplanted stems cells in vivo. 3) Development of Tc-99m and Ga-68 angiogenic SPECT/PET tracers to image expression of VEGF receptors that are involved in tumor angiogenesis and can be important therapeutic targets. 4) Development of the concept of “click therapy” that combines advantages of multi-component targeting, bio-orthogonal conjugation and image guidance and preclinical validation in breast and prostate cancer models.

The Weiss Lab, which features a multi-disciplinary team at Johns Hopkins as well as at Cedars Sinai Medical Center in Los Angeles, is dedicated to identifying the most important clinical, genetic, structural, contractile and metabolic causes of sudden cardiac death as well as the means to reverse the underlying pathology and lower risk. Current projects include research into energy metabolism in human heart failure and creatine kinase metabolism in animal models of heart failure. Robert G. Weiss, MD, is professor of medicine, Radiology and Radiological Science, at the Johns Hopkins University.

Research in the Wojciech Zbijewski Lab — a component of the Imaging for Surgery, Therapy and Radiology (I-STAR) Lab — focuses on system modeling techniques to optimize the x-ray CT imaging chain. We’re specifically interested in: 1) using numerical models to improve the task-based optimization of image quality; 2) exploring advanced modeling of physics in statistical reconstruction; 3) using accelerated Monte Carlo methods in CT imaging; and 4) conducting experimental validation of such approaches and applying them to the development of new imaging methods.

The Raman laboratory is within the Division of Cancer Imaging Research in the Department of Radiology and Radiological Science. The focus of the laboratory is bench-to-bed side cancer research. We integrate molecular and cellular biology, developmental biology, cancer biology, molecular imaging techniques to study cancer formation and progression. Many of the projects in the lab investigate dysregulated genes in cancer and the translatability of this information to a clinical setting. One such project is to functionally decipher the role of a RNA helicase gene, DDX3, in the biogenesis of multiple cancer types such as breast, lung, brain, sarcoma, colorectal and prostate. Additionally, using a rational drug design approach, a small molecule inhibitor of DDX3 (RK-33) was synthesized and its potential for clinical translation is being investigated.

The Lima Lab’s research is concentrated on the development and application of imaging and technology to address scientific and clinical problems involving the heart and vascular system. Specifically, our research is focused on developing magnetic resonance imaging (MRI) contrast techniques to investigate microvascular function in patients and experimental animals with myocardial infarction; functional reserve secondary to dobutamine stimulation and myocardial viability assessed by sodium imaging; and cardiac MRI and computed tomography (CT) program development of techniques to characterize atherosclerosis in humans with cardiovascular or cerebrovascular disease. Current projects include: • The Coronary Artery Risk Development in Young Adults (CARDIA) Study • The MESA (Multi-Ethnic Study of Atherosclerosis) Study • The Coronary Artery Evaluation using 64-row Multidetector Computed Tomography Angiography (CORE64) Study Joao Lima, MD, is a professor of medicine, radiology and epidemiology at the Johns Hopkins School of Medicine.