Program Director and Core Director

Charles A. O’Brien, PhD

Professor of Medicine

Department of Internal Medicine

Department of Orthopaedic Surgery

VA Research Scientist


Charles O’Brien, Ph.D., is a Professor of Medicine in the UAMS Division of Endocrinology and the Department of Orthopaedic Surgery and is a CAVHS Research Scientist. He is Director of the Center for Musculoskeletal Disease Research and Director of the Genetic Models CORE that serves UAMS, ACRI, and the CAVHS.  Dr. O’Brien’s research is focused on understanding the cellular and molecular mechanisms that control bone remodeling in health and disease.

I received my PhD in Microbiology and Immunology from the University of Oklahoma Health Sciences Center in 1990 and performed my postdoctoral training in the Department of Cell Biology at Yale University.  I joined the Division of Endocrinology at the University of Arkansas for Medical Sciences in 1994.  The primary focus of my laboratory has been to understand the cellular and molecular mechanisms that control bone remodeling, especially in conditions such as glucocorticoid excess and aging.  Most recently, our efforts have been focused on osteocytes.  We have found that osteocytes produce RANKL, a factor that is essential for the differentiation of osteoclasts. Therefore, changes in RANKL production may be important for different types of pathological bone loss.  In all of these studies, we utilize genetically-modified mice, which have become an area of expertise for me and I have been the director of the UAMS Genetic Models Core since 2004.  I have been designing and generating transgenic mice since 1997, gene-targeted mice since 2004, and gene-edited mice since 2014.  Our core has produced over 300 founder mice from more than 40 different DNA constructs and provides other essential services related to the maintenance of genetically-modified mouse strains.  My other major focus is the development and mentoring of junior faculty.  Our division has a strong record of helping early-stage investigators to develop productive programs and to achieve independent federal funding.  In 2018, we received P20 funding from NIH/NIGMS to expand these efforts and to develop the Center for Musculoskeletal Disease Research.  I have been funded by the NIH since 1998 and by the Veteran’s Administration since 2009″.

Complete list of published work also in GoogleScholar:


Associate Director of Administrative Core and Mentor

Maria Schuller Almeida, Ph.D.

Associate Professor

University of Arkansas for Medical Sciences
4301 W. Markham St.
Little Rock, AR 72205

Phone: 501-686 7856


Maria Schuller Almeida, Ph.D., is a Professor with a background in marine biology. She received her degree from the Instituto de Ciências Biomédicas de Abel Salazar, Portugal. Prior to joining UAMS seven years ago, she conducted research in the mineralization of oysters, in her native Portugal and the National History Museum in Paris, France. Her current research focus is on the effects of anti-oxidant defense mechanisms on bone health and disease.

Program Manager

Dhivya Suresh, M.A.

University of Arkansas for Medical Sciences
4301 W. Markham St.
Little Rock, AR 72205

Phone: 501-686-5130 Ext 8980