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MIT Electrical Engineering and Computer Science
EECS Event |
Tuesday, February 20, 2001
4:00 PM (reception following)
Room 35-225
LIDS Colloquium
Abstract
In the post-genomic era, systems approaches will be required to transform the vast amount of new information into new understanding of the organization and function of the complex biological mechanisms that sustain life. The dynamic character of these mechanisms and the prevalence of feedback regulation strategies in their operation make them amenable to systematic mathematical analysis using the same tools that have been used with remarkable success in analyzing and designing engineering control systems. This seems to be the case at all levels of organization, from the system level down to the cellular and molecular levels. In this talk, we examine one such mechanism: the calcium homeostatic system.
For humans and other mammals, maintaining a constant concentration of blood plasma calcium is crucial. Normally, maintaining such concentrations is accomplished by an effective feedback control mechanism. At parturition, however, the sudden increased demand for calcium and the associated hypocalcemia can stress this system tremendously. The large deviations in the calcium concentration that develop and the subsequent adaptation cannot be properly understood without understanding the dynamics of the underlying feedback mechanism. We show that this understanding also provides a clear explanation of the function and the dynamic role of key hormones. It also sheds new light on the causes of certain calcium homeostatic disorders.