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.

A. Laboratory activities include the use of accelerator mass spectrometry (AMS) techniques to measure intracellular drugs and drugs metabolites. AMS is a highly sensitive method for detecting tracer amounts of radio-labeled molecules in cells, tissues, and body fluids. We have been able to measure intracellular zidovudine triphosphate (the active anabolite of zidovudine) in peripheral blood mononuclear cells from healthy volunteers given small doses of 14C-zidovudine, and have directly compared the sensitivity of AMS to traditional LC/MS methods carried out in our laboratory. B. Clinical research activities investigate the clinical pharmacology of new anti-HIV therapies and drug combinations. Specific drug classes studied include HIV reverse transcriptase inhibitors, protease inhibitors, entry inhibitors (selective CCR5 and CXCR4 antagonists), and integrase inhibitors. Scientific objectives of clinical studies include characterization of early drug activity, toxicity, and pharmacokinetics. Additional objectives are characterization of pathways of drug metabolism, and identification of clinically significant harmful and beneficial drug interactions mediated by hepatic and intestinal cytochrome P450 isoforms.

The Lane laboratory is focused on understanding molecular mechanisms underlying chronic rhinosinusitis, particularly the pathogenesis of nasal polyps, as well as inflammation on the olfactory epithelium. Diverse techniques in molecular biology, immunology, and physiology are utilized to study epithelial cell innate immunity, olfactory loss, and response to viral infection. Ongoing work explores how epithelial cells of the sinuses and olfactory mucosa participate in the immune response and contribute to chronic inflammation. The lab creates and employs transgenic mouse models of chronic nasal/sinus inflammation to support research in this area. Collaborations are in place with the School of Public Health to explore mechanisms of anti-viral immunity in influenza and COVID-19.

The Daniel Kuespert Lab conducts research on a range of topics within bioengineering. Past studies include exploring microscale behavior in amphiphilic fluid mixtures predicted by the SAFT equation as well as local order and microphase formation in fluids containing asymmetric molecules.

Research in the Raymond Reid Lab focuses on community health and pediatric infectious diseases among Native American populations; epidemiologic studies of enteric infections, Haemophilus influenzae, and pneumococcus; and field testing of vaccines and treatments.