MicroRNA-223 coordinates cholesterol homeostasis

Results from this study represent a breakthrough in our understanding of posttranscriptional control of cholesterol metabolism and how microRNAs (miRNAs) are at the heart of cholesterol regulatory circuitry and homeostasis. Although cells are adept at maintaining proper cholesterol levels, it was unknown how cells posttranscriptionally coordinate cholesterol uptake, efflux, and synthesis. MicroRNA-223 (miR-223) transcription and expression are maintained by cholesterol, and, as a feedback network, miR-223 inhibits cholesterol biosynthesis and uptake and increases cholesterol efflux. This study clearly demonstrates the extensive role that miRNAs play in coordinating metabolic adaptation to disease and general homeostasis. This work highlights a unique regulatory control point for cholesterol homeostasis and illustrates how important the study of miRNAs is to the greater understanding of dyslipidemia and cardiovascular disease

The dynamics of the ventricular wall and some observations on blood flow.

An expression for the energy of motion of the wall of the left ventricle is developed. A cylinderical model is assumed for the left ventricle, and symmetry is used to produce the problem to a two-dimensional problem. Result obtained indicate that consideration of the energy of motion can be useful in problems of clinical diagnosis. Some correlation between previously published experimental results is also made with the equations derived in this paper