The central focus of the work in Dr. Almon’s laboratory is developing mathematical models that describe complex phenomena in biological systems. A central vehicle for this work is the class of anti-inflammatory/immunosuppressive drugs known as corticosteroids. This important class of drugs has severe side effects which include muscle atrophy, osteoporosis, insulin resistant diabetes, arthrosclerosis and, hypertension. These systemic pathologies derive from the combined effect of corticosteroids on many different tissues. Experimentally, we use the drug as a defined input perturbation to populations of animals and use destructive sampling to evaluate the response over time. Associated with the interest in corticosteroids is the study of systems phenomena that relate either to the use of corticosteroids such as arthritis or to the pathologies caused by corticosteroid such as diabetes and muscle wasting. Our approach is to treat all measurements on a population of animals as derived if they were derived from one “giant rat”. We then try to develop quantitative models that explain how gene expression changes in multiple tissues (liver, skeletal muscle, kidney, adipose tissue) cause complex systemic response responses. The intent is to integrate systemic physiological measurements such as blood glucose or lipid profiles with broad changes in gene expression in multiple tissues.