Track I – Physician-Scientist (Basic Research)

The discoveries found in basic science laboratories provide the basis of future therapies. Our basic science research track trains fellows in the scientific method and provides hands-on experience in hypothesis-testing research. The environment for research in Developmental Biology is particularly rich on the Duke campus. Research opportunities range from stem cell biology to studying genomics and proteomics in transgenic zebrafish and mice. Fellows have the opportunity to learn a diverse array of molecular and cellular techniques including physiological functional studies at the whole animal or organ level as well as in single cells. Opportunities for basic research are offered below:

 

i. Developmental Biology - Cardiovascular & Neurodevelopment:

Page A. W. Anderson, M.D.:

Dr. Page A. W. Anderson, Professor of Pediatrics, Vice Chair for Research, has a broad-based research program that studies cardiac myofilament proteins, the pathobiology of heart disease, and stem cell differentiation in the heart. The recognition of Dr. Anderson’s scientific program is evidenced by his being funded continuously by the NIH since 1978, his being named Chair of the NHLBI study section, Cardiovascular A, and his participation and membership in multiple other NIH review groups.

His investigation of complement activation and its role in the inflammatory post-cardiopulmonary bypass syndrome includes studies in the animal and in the infant. His demonstration that blockade of the complement cascades is protective of myofilament, cardiac, and lung function in the neonatal pig led to a phase I/II trail in infants. The promising results of this trial have led to subsequent phase II trials in infants. The findings in the patient have led back to experiments at the single cell level to examine the mechanisms through which complement activation results in abnormal cardiac myocyte function.

His studies of cardiac protein isoform expression focus on cardiac troponin T, essential in cardiac contraction. His laboratory was the first to identify in the human and in other species multiple isoforms of cardiac troponin T and to demonstrate a correlation between myofibrillar ATPase activity and troponin T isoform expression in myocardium from the normal and failing human heart. These functional results were supported by his subsequent study in the infant. His laboratory is presently studying the consequences of transgenic expression of these isoforms in experiments that study the healthy and cardiomyopathic heart and that range from the single cell to the intact animal.

His laboratory in collaboration with Dr. Peggy Kirby of Duke University and Dr. Nadia Malouf at the University of North Carolina at Chapel Hill is using a clonal stem cell line, derived from an adult animal, to study engraftment and differentiation. They have demonstrated that these clonal cells differentiate into endothelial cells and myocytes in mouse and rat heart in vivo and are incorporated into the chick embryo. The ongoing studies are focusing on the biology of engraftment and differentiation and the consequences of these processes on embryogenesis and organ function in the normal animal and animal models of human diseases.

Dr. Anderson is the Principal Investigator of the Duke Clinical Center in the NHLBI funded Pediatric Heart Disease Network. The multi-Center network aims to carry out clinical trials that range from the treatment of the pediatric patient with a functional single ventricle to the patient with Kawasaki’s disease. Dr. Anderson, in collaboration with Drs. Li and Sanders and other members of his Division, will help design and carry out these clinical trials.

Altogether this diverse and rich clinical and basic science research program that incorporates molecular and cell biology, physiology, and pathology will provide strong research experiences for the program’s trainees.

Tony Creazzo, PhD, Associate Professor of Pediatrics (Neonatology) and Cell Biology, Mentor:

Dr. Creazzo’s research interest is in calcium channels, excitation-contraction coupling and cardiac rhythmicity in development. Specifically, he is interested in the functional assembly as well as transcriptional regulation of the various molecular components of excitation-contraction coupling as they are assembled during development and secondly, in the development of cardiac pacemaking mechanisms including the involvement of the sodium/calcium exchanger, T-type calcium channels and potassium channels. He is also interested in cardiac excitation-contraction coupling mechanisms that regulate cytosolic calcium in congenital heart disease.

Brigid L.M. Hogan, PhD, FRS, Professor and Chairman of Cell Biology, Mentor:

Dr. Hogan is interested in the molecular mechanisms regulating the growth, differentiation, and patterning of the mouse embryo. Of particular interest are genes involved in the elaboration of complex organs such as the lungs from small, undifferentiated rudiments, and the development of primordial germ cells.

Joseph Izatt, Ph.D., Associate Professor, Department of Biomedical Engineering, Mentor:

Dr. Izatt’s research concentrates on optical coherence tomography (OCT) and its applications to biomedical imaging. OCT allows subsurface imaging at the micron level using light, with present applications to developmental biology models and human clinical imaging. Collaboration with Dr. Margaret Kirby has allowed three dimensional imaging of cardiac morphology and development in the chick embryo. Human clinical research is actively ongoing including ophthalmologic applications of OCT in retinal imaging and gastrointestinal endoscopic imaging utilizing OCT. New research is focusing on the development of molecular contrasts to complement OCT imaging. Dr. Izatt serves as Director of the Laboratory for Biophotonics at the Fitzpatrick Center for Photonics and Communications Systems at Duke University.

Margaret Kirby, Ph.D., Cardiac and Brain Morphogenesis, Mentor:

Dr. Margaret Kirby, Professor of Pediatrics, is internationally recognized for her studies of embryogenesis. Dr. Kirby and her research team were recruited to our Department of Pediatrics in the Spring of 2001. The excellence of her research is reflected in her NIH funding that includes her program project grant: Development of the Heart: Role of Neural Crest. She has served as a member of multiple editorial boards, including those of the American Journal of Anatomy, Circulation, Circulation Research, Pediatric Cardiology, and Embryo. Her service on NIH review committees includes being a member of the Program Project Review Committee A of NHLBI.

Dr. Kirby proposed and tested the hypothesis that neural crest cell function is essential for normal structural and functional development of the heart and great arteries. She established this neural crest cell model as the first proven experimental model to explain congenital cardiac malformations. Her laboratory demonstrated that cardiovascular, thymus, and parathyroid development depend on the migration and incorporation of neural crest cells into these structures. In the context of ventricular dysrhythmias in patients with congenital cardiac defects, her laboratory has also documented that myocardial excitation-contraction coupling is impaired in the embryonic heart in the absence of neural crest cells. The establishment of the neural crest cell model in chick embryos has led to it being the gold standard in analyzing the phenotype of transgenic and mutant mice with defective heart development.

Recently, Dr. Kirby has developed a modification of her neural crest cell theory based on the presence of a midline stripe that is an organizer for brain, face, and heart development. This model provides a unifying concept for commonly recognized clinical syndromes in which abnormal midface, neural, and heart development are present.

The goal of her research is to establish the mechanisms of signal coordination by neural crest cells in the pharynx and to determine the factors that alter neural crest cell migration and function. These signals are required for outflow and inflow tract development. She has recently described a novel secondary heart field that depends upon these signals in providing definitive myocardium. Her laboratory will provide the trainees a rich basic science research environment in the molecular and cell biology study of the mechanisms underlying normal embryonic development.

John Klingensmith, Ph.D., Cell Biology, Mentor:

Dr. Klingensmith is an Assistant Professor of Cell Biology at Duke University Medical Center. His graduate training was in genetics at Harvard and in developmental biology at Stanford, and his postdoctoral work was in mammalian embryology at Toronto. He has been an independent investigator at Duke since January 1998. He holds two NIH grants, one on craniofacial development and the other on neural tube development. He is a prominent educator in the Department of Cell Biology for graduate students in developmental biology and genetics. He also teaches a laboratory course to first year medical students at Duke University Medical School. Dr. Klingensmith has served on several graduate admissions committees and faculty search committees, and is a peer reviewer of grants and manuscripts . However, his primary work is basic research in mammalian development and birth defects, for which he received a Presidential Early Career Award (PECASE) from President Bush at the White House in July, 2002. Dr. Klingensmith’s lab will provide an excellent basic research opportunity for study of the relationship between brain and heart development. The interactions between Dr. Klingensmith and Drs. Kirby and Creazzo will facilitate and expand the breadth of research opportunities possible.

ii. Neonatal Lung Development and Repair:

The environment for research in neonatal lung development and repair is also excellent. Research opportunities include: alterations in gas transport and sepsis-associated lung injury, pulmonary and cardiovascular physiology, gas transport, and coagulation-mediated lung injury, nitric oxide and reactive oxygen species biology and biochemistry, surfactant, cell biological and organ explant methods of manipulating lung development with state-of-the-art morphometric reconstruction of the developing lung. A particular strength of this program is the opportunity for a fellow to use an acute lung injury model in the adult baboon

Richard L. Auten, MD, Associate Professor of Pediatrics (Neonatology), Program Leader, Mentor:

Dr. Auten’s interests are in modulation of inflammatory response/oxidative injury during the newborn lung injury in rodent models of chronic lung disease of prematurity, targeting neutrophil and macrophage chemokinesis/function and cellular oxidative injury to preserve normal lung development. He is studying the effects of enhanced anti-oxidant enzyme expression on late lung development, using transgenic mice and gene transfer to achieve overexpression of extracellular superoxide dismutase during postnatal oxidant stress.

Ronald N. Goldberg, MD, Professor of Pediatrics, Director of Neonatology, Principle Investigator, Mentor:

Dr. Goldberg’s interests include the cardiovascular manifestations of sepsis and septic shock in the neonate with specific attention to the role of cytokines and nitric oxide and the use of nitric oxide and ethyl nitrite in persistent pulmonary hypertension. In addition, he has been involved in clinical research and Multicenter Collaboration involving nitric oxide, surfactant and high frequency ventilation. He is the PI representing Duke in the NICHD Neonatal Network and has recently been the recipient, along with Dr. Jonathan Stamler, of the Duke Translational Medicine Research Award.

Claude Piantadosi, MD, Professor of Medicine, Mentor:

Dr. Piantadosi's research work focuses on regulation of oxidative metabolism, oxidative stress, and nitric oxide biology in the lung and other tissues. A portion of the work is devoted to understanding the roles of oxidative and nitrosative stress during acute lung injury. Acute lung injury is produced in laboratory animals and in isolated perfused lungs by exposure to oxygen, ischemia or endotoxin, or other inflammatory mediators. The physiological, biochemical and molecular responses of the lung are measured during the evolution of oxidative stress in order to understand the mechanism of the injury and thereby be able to prevent it with specific interventions. A second portion of the work is devoted to understanding the responses of non-pulmonary organs to acute lung injury produced by sepsis and septic shock. This work focuses on the central role of the mitochondrion in energy provision and cell signaling of programmed cell death (apoptosis). The laboratory has a special expertise recognized on a national level in mechanisms of acute lung injury and in particular the roles of oxygen and nitric oxide in the physiological and pathological responses to such injuries.

Jo Rae Wright, PhD, Professor of Cell Biology, Mentor:

Dr. Wright studies the functions of pulmonary epithelial and immune cells at the cellular and molecular level. These two types of cells carry out functions that are important for normal breathing and for preventing infection. The alveolar epithelial type II cell synthesizes a substance known as surfactant, which is a soap-like mixture of lipids and proteins that reduces surface tension in the lung and makes normal breathing possible. One aspect of her research is directed toward understanding the metabolism and clearance of surfactant and the role that receptors and surfactant proteins play in regulating surfactant pool size. The type II cell, in addition to synthesizing surfactant, participates in surfactant clearance by endocytosis. Surfactant proteins bind to cell surface receptors and the receptor/ligand complex is internalized via endocytosis. Within the cells, proteins and lipids are sorted to either degradative or secretory pathways. Her group is currently attempting to isolate the type II cell receptor, define the molecules and pathways involved in intracellular targeting of surfactant, and determine the factors that regulate endocytosis. Two of the surfactant proteins have been shown to be homologous to serum proteins that bind carbohydrates and are involved in non-antibody mediated host defense against infection. This observation has generated a new area of research on the immunomodulatory functions of surfactant proteins. In an effort to understand the mechanism by which these proteins affect immune cell function, Dr. Wright’s lab is producing chimeric molecules of serum and surfactant proteins and attempting to isolate the cell surface receptors that interact with surfactant proteins. Studies are also underway to define the effects of surfactant proteins on regulation of immune cell function and prevention of lung disease.

Jonathan S. Stamler, MD, Professor of Medicine and Biochemistry, Associate Investigator of the Howard Hughes Medical Institute, Mentor:

Dr. Stamler is a member of the new Translational Medicine Initiative (TMI) at Duke. He is internationally recognized for his study of NO and its role in normal and pathophysiological conditions. The impact of his studies is emphasized by his multiple publications in Nature, Science, Cell, and The Proceedings of the National Academy of Sciences, USA. Dr. Stamler is a member of the American Association of Physicians and has received many awards for his research. In 2000, he was an ASCI prize finalist, and in 2001 the AFMR prize winner. Dr. Stamler’s research focuses on the regulation of redox systems as they relate to complex physiological responses, focusing specifically on nitric oxide (NO). By studying the molecular details of the interactions of NO with thiol and transition metal-containing proteins, insights are gained into the molecular basis of redox sensitivity in biological systems, and new molecules can be generated with therapeutic applications. The role of redox systems in organ damage, for example hyperoxia, hypoxia, and pulmonary hypertension, make studies of this system very relevant to the training of the pediatric investigator.

Neil R. MacIntyre, MD, Professor of Medicine, Mentor:

Dr. MacIntyre is interested in pulmonary gas exchange during acute and chronic lung disease and assessment of regional differences in pulmonary diffusing capacity. He is also interested in applications of high frequency jet ventilation to enhance gas exchange and/or decrease pulmonary barotrauma, determination of the effects of different types of mechanical ventilation on the work of breathing and weaning from mechanical ventilation.

 

iii. Neural Injury and Repair in the Fetus and Neonate:

Opportunities for fellow research in neural injury and repair are excellent. The NPRI has a fully equipped laboratory within the Multidisciplinary Neuroprotection Laboratory and has access to any of the techniques or models used. This program encompasses a number of models of central nervous system injury including stroke, head injury and hypoxic ischemia injury in neonatal rats and mice. The fellow will have access to laboratory facilities to investigate basic mechanism of acute brain injury and potential pharmacologic interventions using whole animal and molecular biology techniques.

Daniel Laskowitz, MD, Associate Professor of Medicine (Neurology) and Neurobiology, Mentor:

Dr. Laskowitz’s laboratory uses molecular biology, cell culture, and animal modeling techiniques to examine the CNS response to acute injury. In particular, his laboratory examines the role of microglial activation and the endogenous CNS inflammatory response in exacerbating the secondary injury following acute brain insult. Much of the in vitro work in his laboratory is dedicated to elucidating cellular responses to injury with the ultimate goal of exploring new therapeutic interventions in the clinical setting of stroke, intracranial hemorrhage, and closed head injury. In conjunction with the Multidisciplinary Neuroprotection Laboratories, he also focuses on clinically relevant small animal models of acute CNS injury. The laboratory uses murine models of closed head injury, subarachnoid hemorrhage, intracranial hemorrhage, and perinatal hypoxia-ichemia, in addition to the standard rodent models of focal stroke and transient forebrain ischemia. Recently he has adapted several of these models from the rat to the mouse to take advantage of the murine transgenic technology.

James McNamara, MD, Carl R. Deane Professor of Neuroscience, and Chair, Department of Neurobiology; Professor of Medicine (Neurology); Director, Center for Translational Neuroscience; Mentor:

Dr. McNamara’s research is centered on mechanisms of neuronal injury and death following a diversity of neurotoxic insults. These insults can arise from ischemic, hypoxic, and traumatic events as well as poisoning by environmental agents such as carbon monoxide. Receptors for glutamate, the principal excitatory transmitter in the mammalian nervous system, are pivotal in mediating these toxic insults. Models used in his research include in vivo models in mice and multiple in vitro models, including neurons in primary culture, and organotypic explant cultures.

David Warner, MD, Professor of Anesthesiology, Neurobiology and Surgery, Mentor: Stroke, cerebral vasospasm, and head injury can be catastrophic diseases.

Dr. Warner’s multidisciplinary neuroprotective laboratory is dedicated to examining the pathophysiologic basis of and therapeutic modalities for treatment of these disorders. In vivo rodent models are established with requisite physiologic control. Experimental techniques include intracerebral microdialysis, neurochemistry, electrophysiology, measurement of cerebral blood flow and metabolic rate, neurohistology, image analysis, and neurobehavior. In vitro techniques include use of primary neuronal cultures and organotypic hippocampal slices in assays of excitotoxicity and calcium transients. Therapeutic protocols examine effects of anesthetic agents, induced hypothermia, excitatory neurotransmitter antagonists, free radical scavengers, and allosteric modulators of hemoglobin affinity for oxygen on outcome from brain injury. Transgenic and knockout murine models are used to examine the roles of human apolipoprotein E isoforms and human extracellular superoxide dismutase in global and focal cerebral ischemia and head injury.