Dynamic SPECT measurement of absolute myocardial blood flow in a porcine model.

Unlabelled: Absolute myocardial blood flow (MBF) and myocardial flow reserve (MFR) provide incremental diagnostic and prognostic information over relative perfusion alone. Recent development of dedicated cardiac SPECT cameras with better sensitivity and temporal resolution make dynamic SPECT imaging more practical. In this study, we evaluate the measurement of MBF using a multipinhole dedicated cardiac SPECT camera in a pig model of rest and transient occlusion at stress using 3 common tracers: (201)Tl, (99m)Tc-tetrofosmin, and (99m)Tc-sestamibi.

Characterization of the four isomers of (123)I-CMICE-013: a potential SPECT myocardial perfusion imaging agent.

Unlabelled: Myocardial perfusion imaging (MPI) with single photon emission computed tomography (SPECT) is widely used in the assessment of coronary artery disease (CAD). We have developed (123)I-CMICE-013 based on rotenone, a mitochondrial complex I (MC-1) inhibitor, as a promising new MPI agent. Our synthesis results in a mixture of four species of (123)I-CMICE-013 A, B, C, D.

Biodistribution and radiodosimetry of a novel myocardial perfusion tracer 123I-CMICE-013 in healthy rats.

Background: 123I-CMICE-013 is a novel radiotracer previously reported to have promising characteristics for single-photon emission computed tomography (SPECT) myocardial perfusion imaging. We evaluated the biokinetics and radiodosimetry of this rotenone-like 123I-labeled tracer in a microSPECT imaging-based study.

Methods: 37 to 111 MBq of 123I-CMICE-013 was synthesized and administered intravenously to 14 healthy rats.

Toxicological evaluation of a rotenone derivative in rodents for clinical myocardial perfusion imaging.

Myocardial perfusion scintigraphy is a valuable clinical tool for assessing coronary blood flow deficits in patients. We recently synthesized a new iodinated compound ((123)I-CMICE-013) based on rotenone and showed that it has excellent performance as a radiotracer for myocardial perfusion imaging. Here, we describe the cellular toxicity and subacute toxicity of CMICE-013 in rats.

Synthesis and characterization of 123I-CMICE-013: a potential SPECT myocardial perfusion imaging agent.

Unlabelled: Coronary artery disease (CAD) is a major cause of death in Canada and the United States. Single photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI) is a useful diagnostic test in the management of patients with CAD. The widely used SPECT MPI agents, (99m)Tc sestamibi and (99m)Tc tetrofosmin, exhibit less than ideal pharmacokinetic properties with decreasing uptake with higher flows.

Intravascular and extravascular microvessel formation in chronic total occlusions a micro-CT imaging study.

Objectives: The purpose of this study was to characterize the 3-dimensional structure of intravascular and extravascular microvessels during chronic total occlusion (CTO) maturation in a rabbit model.

Background: Intravascular microchannels are an important component of a CTO and may predict guidewire crossability. However, temporal changes in the structure and geographic localization of these microvessels are poorly understood.

Natural history of experimental arterial chronic total occlusions.

Objectives: We sought to perform the first systematic study of the natural history of chronic total arterial occlusions (CTOs) in an experimental model.

Background: Angioplasty of CTOs has low success rates. The structural and perfusion changes during CTO maturation, which may adversely affect angioplasty outcome, have not been systematically studied.

Severe hemodilutional anemia increases cerebral tissue injury following acute neurotrauma.

Anemia may worsen neurological outcomes following traumatic brain injury (TBI) by undefined mechanisms. We hypothesized that hemodilutional anemia accentuates hypoxic cerebral injury following TBI. Anesthetized rats underwent unilateral TBI or sham injury (n > or = 7).

Hypoxia alters the expression of inhibitor of apoptosis proteins after brain trauma in the mouse.

Hypoxia worsens brain injury following trauma, but the mechanisms remain unclear. The purpose of this study was to determine the effect of traumatic brain injury (TBI) and secondary hypoxia (9% oxygen) on apoptosis-related protein expression, cell death, and behavior. Using a murine weight-drop model, TBI led to an early (6 h) increase followed by a later (24 h) decrease in neuronal apoptosis inhibitor protein (NAIP) expression in the olfactory and motor cortex; in contrast, TBI led to a sustained (6 h to 7 days) increase in NAIP in the striatum.