A human cell model for dynamic testing of MR contrast agents.

To determine the initial feasibility of using magnetic resonance (MR) imaging to detect early atherosclerosis, we investigated inflammatory cells labeled with a positive contrast agent in an endothelial cell-based testing system. The human monocytic cell line THP-1 was labeled by overnight incubation with a gadolinium colloid (Gado CELLTrack) prior to determination of the in vitro release profile from T1-weighted MR images. Next, MR signals arising from both a synthetic model of THP-1/human umbilical vein endothelial cell (HUVEC) accumulation and the dynamic adhesion of THP-1 cells to activated HUVECs under flow were obtained.

Feedback control of retrograde peristalsis using Neural Gastric Electrical Stimulation.

Neural Gastric Electrical Stimulation (NGES) is a new method for invoking gastric contractions under microprocessor control. However, optimization of this technique using feedback mechanisms to minimize power consumption and maximize effectiveness has been lacking. The present work proposes a prototype feedback-controlled neural gastric electrical stimulator for the treatment of obesity.