Total body fat content and fat topography are associated differently with in vivo glucose metabolism in nonobese and obese nondiabetic women

n this study, total body fat content and fat topography were related to glucose metabolism in the basal and insulin-stimulated states in 18 nonobese and 18 obese premenopausal nondiabetic women. All subjects received a euglycemic insulin (20 mU.min-1.m2) clamp study in combination with [3-3H]-D-glucose infusion and indirect calorimetry to quantitate total body glucose uptake, glucose oxidation, and nonoxidative glucose disposal. Total body fat content was determined with tritiated water, whereas body fat distribution was estimated from the WHR, the STR, and the VSR (measured by magnetic resonance imaging). In the postabsorptive state, total body glucose utilization, glucose oxidation, and nonoxidative glucose disposal rates were similar in nonobese and obese women, whereas during the insulin clamp all three metabolic parameters were reduced significantly in the obese group. In nonobese women, total body fat content was related inversely to both total and nonoxidative glucose disposal during the insulin clamp, whereas no relationship was found between glucose metabolism (total, oxidative, and nonoxidative) and WHR, STR, or VSR. In contrast, in obese women, no relationship was observed between total body fat content and any measure of insulin-mediated glucose metabolism. However, both WHR and VSR were related inversely to total, oxidative, and nonoxidative glucose disposal rates during the insulin clamp. These results suggest that total body fat content and body fat topography are associated differently with insulin-mediated glucose metabolism in nonobese and obese women. In the nonobese women, total body fat mass appears to be a primary determinant of tissue sensitivity to insulin, whereas in obese women, body fat topography exerts a more dominant effect

Total body fat content and fat topography are associated differently with in vivo glucose metabolism in nonobese and obese nondiabetic women

In this study, total body fat content and fat topography were related to glucose metabolism in the basal and insulin-stimulated states in 18 nonobese and 18 obese premenopausal nondiabetic women. All subjects received a euglycemic insulin (20 mU.min-1.m2) clamp study in combination with [3-3H]-D-glucose infusion and indirect calorimetry to quantitate total body glucose uptake, glucose oxidation, and nonoxidative glucose disposal. Total body fat content was determined with tritiated water, whereas body fat distribution was estimated from the WHR, the STR, and the VSR (measured by magnetic resonance imaging). In the postabsorptive state, total body glucose utilization, glucose oxidation, and nonoxidative glucose disposal rates were similar in nonobese and obese women, whereas during the insulin clamp all three metabolic parameters were reduced significantly in the obese group. In nonobese women, total body fat content was related inversely to both total and nonoxidative glucose disposal during the insulin clamp, whereas no relationship was found between glucose metabolism (total, oxidative, and nonoxidative) and WHR, STR, or VSR. In contrast, in obese women, no relationship was observed between total body fat content and any measure of insulin-mediated glucose metabolism. However, both WHR and VSR were related inversely to total, oxidative, and nonoxidative glucose disposal rates during the insulin clamp. These results suggest that total body fat content and body fat topography are associated differently with insulin-mediated glucose metabolism in nonobese and obese women. In the nonobese women, total body fat mass appears to be a primary determinant of tissue sensitivity to insulin, whereas in obese women, body fat topography exerts a more dominant effect

Automated Multidetector Row CT Dataset Segmentation with an Interactive Watershed Transform (IWT) Algorithm: Part 2—Body CT Angiographic and Orthopedic Applications

The preceding manuscript describes the principles behind the Interactive Watershed Transform (IWT) segmentation tool. The purpose of this manuscript is to illustrate the clinical utility of this editing technique for body multidetector row computed tomography (MDCT) imaging. A series of cases demonstrates clinical applications where automated segmentation of skeletal structures with IWT is most useful. Both CT angiography and orthopedic applications are presented

Automated Multidetector Row CT Dataset Segmentation with an Interactive Watershed Transform (IWT) Algorithm: Part 1. Understanding the IWT Technique

Segmentation of volumetric computed tomography (CT) datasets facilitates evaluation of 3D CT angiography renderings, particularly with maximum intensity projection displays. This manuscript describes a novel automated bone editing program that uses an interactive watershed transform (IWT) technique to rapidly extract the skeletal structures from the volume. Advantages of this tool include efficient segmentation of large datasets with minimal need for correction. In the first of this two-part series, the principles of the IWT technique are reviewed, followed by a discussion of clinical utility based on our experience