John F. Griffin

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Canine intervertebral disk herniation (IVDH) is a common, naturally occurring form of spinal cord injury (SCI) that is increasingly being used in pre-clinical evaluation of therapies. Although IVDH bears critical similarities to human SCI with respect to lesion morphology, imaging features, and post-SCI treatment, limited data are available concerning(More)
PURPOSE To analyze four clinically applicable diffusion tensor imaging (DTI) protocols (two each in the transverse and sagittal planes) in the normal dog. MATERIALS AND METHODS Seven healthy Dachshund dogs were scanned with four DTI protocols. Within each plane, identical spatial resolution was used while the number of diffusion-encoding directions and(More)
The conformation of [Leu5]enkephalin is produced by a Tyr-Gly-Gly-Phe beta bend stabilized by antiparallel hydrogen bonding between tyrosine and phenylalanine. On the basis of a comparison of the observed structure with the structure of known opiate agonists, three hydrophilic and two hydrophobic regions have been identified as contributing to the(More)
The purpose of this study was to describe application and machine accuracy for a new computed tomography (CT) guided, frameless, stereotactic brain biopsy system in dogs. Heads from ten canine cadavers were secured to a bite-plate with six attached fiducial markers and imaged using CT. Fiducialized CT images were imported into stereotactic software and(More)
The presence of a molecular scaffold to orient a basic group is important for potent and selective kappa opioid antagonist selectivity. An attempt to determine how the geometry of the scaffold affects this selectivity has led to the synthesis of a bivalent ligand (5) whose linker constrains the N17' basic nitrogen (the "address") to a position that is 6.5 A(More)
Spinal cord injury (SCI) affects thousands of people each year and there are no treatments that dramatically improve clinical outcome. Canine intervertebral disc herniation is a naturally-occurring SCI that has similarities to human injury and can be used as a translational model for evaluating therapeutic interventions. Here, we characterized cerebrospinal(More)
The inactive methadone analog threo-5-methylmethadone has a solid-state conformation in which the nitrogen is antiperiplanar to the tertiary carbon C(4). Since threo-5-methylmethadone exhibits no opioid agonism either in vivo or in vitro, methadone analogs probably do not have this conformation when bound to an opioid receptor. The potent agonist(More)
T2-weighted (T2w) sequences are commonly relied upon in magnetic resonance imaging protocols for the detection of brain lesions in dogs. Previously, the effect of fluid suppression via fluid-attenuated inversion recovery (FLAIR) has been compared to T2-weighting with mixed results. Short tau inversion recovery (STIR) has been reported to increase the(More)
Susceptibility artifacts caused by ferromagnetic implants compromise magnetic resonance imaging (MRI) of the canine stifle after tibial plateau leveling osteotomy (TPLO) procedures. The WARP-turbo spin echo sequence is being developed to mitigate artifacts and utilizes slice encoding for metal artifact reduction. The aim of the current study was to evaluate(More)
The problem our team addresses is best communicated in the following question: Given the number of merchants, consumers, and financial institutions in the U.S., how can we build a record-keeping system that improves the usability, accessibility, and sustainability of consumer transaction records?