Marcus Bell, PhD
Director, Graduate Program in Biomedical Sciences
Professor of Neuroscience, Physiology & Pharmacology
Department of Bio-Medical Sciences
Postdoctoral Fellowship, Thomas Jefferson University
PhD, Biophysics, University of Pennsylvania
BS, Electrical Engineering, University of Pennsylvania
Dr. Bell educates on topics of muscle physiology and neuroscience within several courses
in the Doctor of Osteopathic Medicine program and the Graduate Program in Biomedical
Sciences. In these courses his goal is to break down difficult physical and biochemical
concepts into paradigms that can be comprehended and remembered intuitively for future
understanding the function of the body its response to disease and to osteopathic
and pharmacological interventions. To help foster comprehensive educational approaches
through deliberate, innovative curriculum design and delivery, as well as through
supporting our students at all levels by means of appropriate resources, Dr. Bell
serves on numerous committees involving student academic matters from admission through
graduation. Dr. Bell also directs the Journal Club course for the Biomedical Sciences
Dr. Bell's basic science research has been concentrated in two areas. 1) In his work
with other researchers on the regulatory systems of cardiac and skeletal muscle, he
hopes to elucidate the mechanism by which changes in intracellular calcium are translated
into the varying rate and strength of the muscular contraction. The technique of time-resolved
polarized fluorescence is used to measure motions of the regulatory proteins as calcium
binds to activate the system. The rate and extent of regulatory protein movement is
compared to the rate and extent of force generation. By combining results from fluorescent
probes attached to several sites in the system, a broader understanding of the mechanism
may be achieved. 2) In his collaborations with researchers focused on Alzheimer's
Disease, Dr. Bell investigates the root causes of neuropathological cascades characteristic
of the disease. Of particular interest are the roles of infections agents, such as
C. pneumoniae, in evading the immune response even as they induce host cells to secrete
compounds, such as abnormal amyloid beta protein, that ultimately lead to the death
of neighboring cells in the brain.
Dr. Bell also collaborates in research focused on medical education, and is a member
of the International Association of Medical Science Educators (IAMSE).
Bell, M.G., Dale, R.E., Van der Heide, U.A. and Goldman, Y.E. 2002. Polarized fluorescence depletion
reports orientation distribution and rotational dynamics of muscle cross-bridges.
Biophys. J. 83(2):1050-1073.
Martin, H., Bell, M.G., Ellis-Davies, G.C. and Barsotti R.J. 2004. Activation kinetics of skinned cardiac
muscle by laser photolysis of nitrophenyl-EGTA. Biophys. J. 86(2):978-990.
Bell, M.G., Lankford, E.B., Gonye, G.E., Ellis-Davies, G.C., Martyn, D.A., Regnier, M. and R.J.
Barsotti. 2006. Kinetics of cardiac thin-filament activation probed by fluorescence
polarization of rhodamine-labeled troponin c in skinned guinea pig trabeculae. Biophys
Appelt, D.M., Roupas, M.R., Way, D.S., Bell, M.G., Albert, E.V., Hammond, C.J. Balin, B.J. 2008. Inhibition of apoptosis in neuronal
cells infected with Chlamydophila (Chlamydia) pneumoniae. BMC Neuroscience 2008, 9:13.
(Earned journal’s “highly accessed” rating.)
Bell, M.G., Barkalow, K., Hamasaki, T. and Satir, P. 1991. Photolysis of caged ATP initiates
dynein-mediated translocation of microtubules. Biophys. J., 59:567a.
Bell, M.G., Matta, J.J., Thomas, D.D. and Goldman, Y.E. 1993. Changes in cross-bridge kinetics
induced by SH-1 modification in rabbit psoas fibers. Biophys. J., 64:252a.
Bell, M.G., Matta, J.J., Thomas, D.D. and Goldman, Y.E. 1995. Changes in cross-bridge kinetics
induced by SH-1 modification in rabbit psoas fibers. Biophys. J., 68:360s.
Bell, M.G., Dale, R.E., Van der Heide, U.A. and Goldman, Y.E. 2000. Polarized fluorescence depletion
reports orientation distribution and rotational dynamics of muscle cross-bridges.
Biophys. J., 78(4):326s.
Martin, H., Hager, R., Bell, M.G. and Barsotti, R.J. 2001. Temperature sensitivity of phosphate-induced tension transients
in skinned cardiac muscle. Biophys. J., 80:586a.
Bell, M.G., Martin, H., Ellis-Davies, G.C.R., Martyn, D.A., Regnier, M. and Barsotti, R.J. 2002.
Kinetics of cardiac thin-filament activation probed by fluorescence polarization of
rhodamine-labeled troponin C. Biophys. J., 82:170a.
Martin, H., Bell, M.G., Hager, R. and Barsotti, R.J. 2003. Effects of Ca2+ and temperature on the force-generating
transition in cardiac muscle studied by photolysis of caged-phosphate. Biophys. J.
Way, D.S., Albert, E.V., Hammond, C.J., Bell, M.G, Balin, B.J. and Appelt, D.M: 2006. Caspase activity is inhibited in neuronal cells
infected with Chlamydia pneumoniae: Implications for apoptosis in Alzheimer’s Disease.
10th ICAD conference, Madrid, Spain.
Elizabeth K. Ruszak, Keren C. McCarthy, Marcus G. Bell, Brian J. Balin, Denah M. Appelt, 2008. Chlamydophila (Chlamydia) pneumoniae promotes
AB 1-42 amyloid processing in Neuronal Cells: A Pathogenic Trigger for Alzheimer’s
Disease. AOA Convention.
Denah M. Appelt, Elizabeth K. Ruszak, Marcus G. Bell, Brian J. Balin. 2008. Increased Aβ 1-42 amyloid processing into oligomers in astrocytes
and neuronal cells infected with Chlamydophila (Chlamydia) pneumoniae. Society for
Hoyt, J.A., Kuchera, M.L., Daghigh, F., Bell, M., Schoenfeldt, B., Overberger, R., Bailey, J. 2008. Comparing Changes in Serum Nitric
Oxide Levels and Heart Rate After Periodic Acceleration Therapy (PAT) Using an AT101TM
Table to Changes Measured After Active Exercise. AOA Annual Convention.
Hoyt, J.A., Kuchera, M.L., Daghigh, F., Bell, M., Schoenfeldt., B., Overberger, R., Bailey, J. 2008. Comparing Changes in Serum Nitric
Oxide Levels and Heart Rate After Osteopathic Manipulative Treatment (OMT) Using Dalrymple
Pedal Pump to Changes Measured After Active Exercise. AOA Annual Convention.
Keith Williams, Juliana Zoga, Susan Hingley, Brian Balin, Denah Appelt, Marcus Bell. 2012. Infection with Chlamydia Pneumoniae alters calcium-associated gene regulation
and processes in neuronal cells and monocytes: Implications for Alzheimer’s Disease.
21st Annual Philadelphia Infection and Immunity Forum.
Marcus Bell, Keith Williams, Juliana Zoga, Susan Hingley, Brian Balin, Denah Appelt. 2012. Alzheimer’s
disease-like changes in calcium associated gene expression and protein regulation
following C. pneumoniae infection of neuronal cells and monocytes. Society for Neuroscience
Victoria Lawn, Matthew Jaffa, Catherine Babbitt-Cook, Burton Mark, Jane Dumsha, Marcus Bell, Denah Appelt. 2012. Reducing the Stigma of Mental Illness Among Medical Students.
AOA Annual Convention.
Christopher A. Cappellini, Ahmad B. Cader, Keith G. Williams, Juliana D. Zoga, Susan
T. Hingley, Brian J. Balin, Denah M. Appelt, Marcus G. Bell Chlamydia pneumoniae infection of neuronal cells induces changes in calcium-associated
gene expression consistent with Alzheimer’s disease, CBRS meeting, 2013.
Denah M. Appelt, Christopher A. Cappellini, Ahmad B. Cader, Keith G. Williams, Juliana
D. Zoga, Susan T. Hingley, Marcus G. Bell, Brian J. Balin, Changes in calcium-related gene expression consistent with Alzheimer’s
disease are initiated by infection of neuronal cells with Chlamydia pneumoniae, AAIC
James M. Brandt, Ahmad B. Cader, Lauren Semler, Christine J. Hammond, Marcus G. Bell, Jenayle L. Smith, Nicol E. Joseph, Morgan Devins, Marisol Velez, Katherine E. Galluzzi,
Balin J. Balin, Denah M. Appelt: Electron microscopy studies elucidate morphological
forms of Chlamydia pneumoniae in blood samples from patients diagnosed with mild cognitive
impairment (MCI) and Alzheimer’s disease (AD); FASEB 2014.
Brian Balin, James Brandt, Christine Hammond, Ahmad Cader, Lauren Semler, Nicol Joseph,
Marcus Bell, Merisol Velez, Morgan Devins, Katherine Galluzzi, Denah Appelt: Biomarkers of infection
with Chlamydia pneumoniae in the geriatric population: a potential diagnostic screen
for cognitive decline? AAIC 2014.
Volunteer & Leadership
Learning Resources Committee, 2014-present
Student Academic Policy & Progress Committee, 2013-present; chair, 2014-present.
DO Student Progress Evaluation Committee, 2013-present.
Biomedical Sciences Student Progress Evaluation Committee, 2012-present.
Program Director, Graduate Program in Biomedical Sciences, 2012-present.
DO Admissions Committee, 2013-present.
Graduate Programs Admissions Committee, 2011-present.
DO Curriculum Committee (non-voting), 2011-present.
Graduate Programs Curriculum Committee, 2011-present.
Director, Biomedical MS Research Concentration, 2009-present.
Biological Imaging Facility, consultant for instrumentation and software, 2001-present.
The President’s Diversity Council, 2013-2014.
Middle States Accreditation, Educational Offerings Self-Study Committee, 2012-2014.
AOA-COCA Accreditation, Student Self-Study Committee, co-chair, 2011-2012.
Institutional Review Board, 2001-2003.
Center for Chronic Disorders of Aging (PCOM), 2012-2013. Dectection of Chlamydia pneumoniae
in blood samples: A diagnostic screen for Alzheimer’s disease. Role: Co-PI.
Center for Chronic Disorders of Aging (PCOM), 2012-2013. Infection with Chlamydia
Pneumoniae alters calcium-associated gene regulation and processes in neuronal cells
and monocytes: Implications for Alzheimer’s disease. Role: PI.
NIH 5R01HL086838-04, 2008-2012. Determinants of Cardiac Thin Filament Regulation.
Co-PI with Robert J. Barsotti, PCOM.
American Heart Grant-In-Aid, 2002-2004, Mechanism of Thin-Filament Based Control of
Cardiac Muscle Contraction. Co-authored with Robert J. Barsotti, Thomas Jefferson
HHS SBIR Phase II, 1996-1998. Sucking Device for Feeding Of Low-Birthweight Infants.
Co-authored with BioFlo, Inc., and KDL Medical Technologies, Inc., Philadelphia.
- Cardiac Function
- Alzheimer's Disease
- Infectious Diseases/Agents
- Medical Education