J. Shen , W. Qu , Y. Wang , S. Choi , D. J. Burgess 1 1 University of Connecticut, 2 U.S. Food and Drug Administration Purpose The objective of the present study was to understand the effect of manufacturing process parameters on the critical physicochemical properties as well as the burst release percentage of peptide microspheres. Methods Leuprolide acetate was chosen as a model peptide and P...

The relationship between hepatic arterial albumin microsphere distribution and hepatic arterial blood flow and the effects of regional angiotensin II were studied in a rat liver metastases model. Hooded-Lister rats were inoculated subcapsularly with 2 x 106 HSN sarcoma cells. At 20 days, hepatic arterial blood flow was measured using the reference microsphere technique. Animals then randomly re...

BACKGROUND Experimental data demonstrate the persistence of a transmural vasodilator reserve in the face of depressed resting myocardial perfusion. The present study was designed to determine whether resting myocardial hypoperfusion indicates exhausted coronary reserve (CR). METHODS AND RESULTS Fifteen patients with stable angina, isolated left anterior descending coronary artery (LAD) stenos...

OBJECTIVES The aim of this study was to evaluate fully quantitative myocardial blood flow (MBF) at a pixel level based on contrast-enhanced first-pass cardiac magnetic resonance (CMR) imaging in dogs and in patients. BACKGROUND Microspheres can quantify MBF in subgram regions of interest, but CMR perfusion imaging may be able to quantify MBF and differentiate blood flow at a much higher resol...

UNLABELLED The aim of this study was to compare the accuracy and reliability of simple methods of quantifying regional cerebral blood flow (rCBF) with 123I-labeled N-isopropyl-p-iodoamphetamine (IMP) and SPECT and to determine which method was best. METHODS Four methods were examined: (a) the microsphere method with continuous withdrawal of arterial blood, which was based on a microsphere mod...

Current treatment protocol for postoperative pain is to infuse anesthetic solution around nerves or into the epidural space. This clinical practice is beset by the short duration of the anesthetic effect unless the infusion is continuous. Continuous infusion, however, requires hospitalization of the patients, thereby increasing medical costs. In addition, it also causes systemic accumulation of...

Direct intramyocardial injection may permit local delivery of protein and gene therapy agents for myocardial and coronary artery disease. Little is known about the immediate fate of materials administered via percutaneous endomyocardial catheters or via surgical epicardial injection. In this study, we use a novel method to evaluate the acute retention of agents injected directly into the myocar...

BACKGROUND The purpose of the present study was to examine whether the effect of coronary stenoses of variable severity on myocardial perfusion can be quantitatively assessed in vivo by analysis of fluorescent cardiac imaging (FCI) compared with the gold standard, the fluorescent microsphere method. FCI is a novel technology to visualize coronary vessels and myocardial perfusion intraoperativel...

The Light Force Accelerometer (LFA) is an optical inertial sensor in which radiation pressure from two counter-propagating laser beams optically confines a glass microsphere. Inertial acceleration of the device results in microsphere displacement along the sensitive axis, which is subsequently nulled by optical forces to provide an acceleration measurement. A simple calculation that takes into ...