Research in the James Knierim Laboratory attempts to understand the flow of information through the hippocampal formation and the computations performed by the various subfields of the hippocampus and its inputs from the entorhinal cortex. To address these issues, we use multi-electrode arrays to record the extracellular action potentials from scores of well-isolated hippocampal neurons in freely moving rats. These neurons, or ""place cells,"" are selectively active when the rat occupies restricted locations in its environment and help to form a cognitive map of the environment. The animal uses this map to navigate efficiently in its environment and to learn and remember important locations. These cells are thought to play a major role in the formation of episodic (autobiographical) memories. Place cells thus constitute a tremendous opportunity to investigate the mechanisms by which the brain transforms sensory input into an internal, cognitive representation of the world and then uses this representation as the framework that organizes and stores memories of past events.

Under the division of Maternal-Fetal Medicine, our Cardio-Obstetric research efforts seek to advance the field of gynecology through medical care and innovation. With a focus on the effect of heart conditions on pregnancy and the ways in which pregnancy can put stress on your heart and circulatory system, our goal in this multi-disciplinary research is that our findings may lead to the development of new treatments or preventative therapies for patients and their babies to better manage a heart condition during pregnancy.

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 Philip Wong Lab seeks to understand the molecular mechanisms and identification of new therapeutic targets of neurodegenerative diseases, particularly Alzheimer's disease (AD) and amyotrophic lateral sclerosis (ALS). Taking advantage of discoveries of genes linked to these diseases (mutant APP and PS in familial AD and mutant SOD1, dynactin p150glued ALS4and ALS2 in familial ALS), our laboratory is taking a molecular/cellular approach, including transgenic, gene targeting and RNAi strategies in mice, to develop models that facilitate our understanding of pathogenesis of disease and the identification and validation of novel targets for mechanism-based therapeutics. Significantly, these mouse models are instrumental for study of disease mechanisms, as well as for design and testing of therapeutic strategies for AD and ALS.

The Balagopal Lab has adapted high-resolution tools to study viruses in situ. Specifically, we were the first to quantify hepatitis C virus (HCV) infection in single hepatocytes by developing single-cell laser capture microdissection (scLCM) and integrating this tool with highly sensitive quantitative real-time PCR. We reported that HCV infects a minority of hepatocytes that are found in geospatial clusters. More recently, we (PIs Balagopal and Thio) integrated scLCM with droplet digital PCR (ddPCR) to reveal the first observations of hepatitis B virus (HBV) infection at single cell resolution in the liver. We found that HBV infects nearly all hepatocytes prior to antiviral therapy. However, during antiviral therapy, HBV infection is diminished while viral transcription is markedly attenuated. Our lab has also focused on HIV-1 infection and immune activation for over a decade. Most recently, we have studied type 1 interferon responses to HIV-1 using RNA sequencing (RNAseq). Using this technology, we identified novel interferon-stimulated genes (ISGs) that are associated with HIV-1 restriction in vivo.

Research in the Jeremy Sugarman Lab focuses on biomedical ethics—particularly, the application of empirical methods and evidence-based standards to the evaluation and analysis of bioethical issues. Our contributions to medical ethics and health policy include work on the ethics of informed consent, umbilical cord blood banking, stem cell research, international HIV prevention research, global health and research oversight.

The Franco D’Alessio Lab investigates key topics within the fields of critical care, internal and pulmonary medicine. We primarily explore immunological determinants of acute lung inflammation and repair. Our lab also investigates age-dependent lung immune response in patients with acute lung injury and acute respiratory distress syndrome (ARDS), regulatory T-cells in lung injury and repair, and modulation of alveolar macrophage innate immune response in ARDS.

The Halushka laboratory is interested in the overarching question of expression localization in tissues. To address this, the laboratory has set out upon several avenues of discovery in the areas of microRNA expression, proteomics and tissue gene expression. Many of these queries relate to the cardiovascular field as Dr. Halushka is a cardiovascular pathologist. Come learn about the science being done in the laboratory.