Search Results
You are looking at 11 - 17 of 17 items for
- Author or Editor: John S. Mattoon x
- Refine by Access: All Content x
Abstract
OBJECTIVE
To radiographically compare patellar ligament length (PLL) in dogs undergoing tibial plateau leveling osteotomy (TPLO) for unilateral cranial cruciate ligament rupture at preoperative, postoperative, and follow-up evaluations.
ANIMALS
105 dogs that underwent TPLO for unilateral cranial cruciate ligament rupture at a referral veterinary hospital from October 1, 2008, through November 30, 2017.
PROCEDURES
Medical records were reviewed to obtain information on dog signalment, surgical procedure, and radiographically measured PLL at preoperative, postoperative, and follow-up evaluations.
RESULTS
Dogs undergoing TPLO had a shorter PLL at the postoperative and follow-up evaluations, compared with the PLL at the preoperative evaluation. Mean ± SD overall unadjusted PLL decreased significantly by 2.3 ± 3.4% between the preoperative and postoperative evaluation and by 2.8 ± 3.9% between the preoperative and follow-up evaluation. The PLL did not differ significantly between the postoperative and follow-up evaluation; mean PLL decreased by 0.4 ± 3.8% between the postoperative and follow-up evaluation.
CONCLUSIONS AND CLINICAL RELEVANCE
The PLL was shorter after TPLO in dogs, which was similar to changes observed for humans after high tibial osteotomy procedures. Further evaluation of clinical assessments, joint mobility, ultrasonographic assessments, and kinematic results are needed to determine the relevance of the PLL and whether a decrease in ligament length results in decreased mobility and persistent lameness in dogs, as has been reported for humans.
Abstract
Objective—To measure the effects of lowmolecular-weight inhibitors on the activity of bovine neutrophil matrix metalloproteinase 9 (MMP-9).
Sample Population—Bovine MMP-9 purified from bovine neutrophilconditioned medium.
Procedures—Neutrophils were degranulated by stimulation with phorbol ester. Enzyme purification was performed by use of gelatin affinity and gel-filtration chromatography. Activated enzyme was incubated with inhibitors prior to addition of substrate (gelatin fluorescein conjugate or fluorogenic peptide). Rates of enzymatic cleavage were determined by monitoring fluorescence as the reactions progressed. Values of IC50 (molar concentration of compound that inhibits specific activity by 50%) and KI (in vitro inhibition constant) were determined.
Results—Rates of enzymatic activity of monomeric and dimeric bovine MMP-9 measured by use of gelatin and peptide substrates were linear with respect to time and concentrations of enzyme and substrate. The MMP-9 was potently inhibited by hydroxamic acids (IC50 for gelatin, 29.2 to 55.7nM; IC50 for peptide, 4.8 to 24.6nM; KI, 0.2 to 0.5nM), whereas tetracyclines (IC50 for gelatin, 30.1 to 112.7MM; IC50 for peptide, 48.0 to 123.8MM; KI, 25.2 to 61.4µM) and chlorhexidine (IC50 for gelatin, 139.1MM; IC50 for peptide, 672.5MM to 1.7mM; KI, 495.0 to 663.0MM) had limited inhibition. Gelatinase-specific inhibitor SB-3CT had intermediate potency (IC50 for peptide, 185.0 to 290.0nM; KI, 66.5 to 86.0nM).
Conclusions and Clinical Relevance—Bovine MMP-9 was potently inhibited by hydroxamic acids and gelatinase inhibitor. These compounds may be useful as modulators of neutrophil-mediated protease activity in cattle.
Abstract
Objectives—To determine whether feed restriction induces hepatic lipidosis (HL) in llamas and to evaluate the metabolic changes that develop during feed restriction.
Animals—8 healthy adult female llamas.
Procedure—Llamas were fed grass hay at a rate of 0.25% of their body weight per day for 13 to 28 days. Llamas were monitored by use of clinical observation, serum biochemical analyses, and ultrasound-guided liver biopsies.
Results—All 8 llamas lost weight and mobilized fat. Five llamas developed HL, including 4 that were nursing crias. During the period of feed restriction, mean serum concentration of bile acids and activities of aspartate aminotransferase (AST), sorbitol dehydrogenase (SDH), and γ-glutamyl transferase (GGT) were significantly higher in llamas that developed HL, compared with llamas that did not. Mean insulin-to-cortisol concentration ratios were lower in llamas with HL before and up to 7 days of feed restriction, compared with those that did not develop HL.
Conclusions and Clinical Relevance—HL in llamas may be induced by severe feed restriction, particularly in the face of increased energy demand. Llamas with weight loss attributable to inadequate dietary intake may develop biochemical evidence of hepatopathy and HL. Increases in serum concentration of bile acids and activities of GGT, AST, and SDH may indicate the development of HL in llamas and identify affected animals for aggressive therapeutic intervention. (Am J Vet Res 2001;62:1081–1087)
Abstract
Objective—To describe the signalment, clinical features, and most common MRI characteristics in dogs with diskospondylitis and investigate whether a correlation exists between the degree of spinal cord compression and neurologic status of the patient.
Design—Retrospective case series.
Animals—23 dogs.
Procedures—The medical records and imaging database of the Veterinary Teaching Hospital at Washington State University were retrospectively cross-referenced for cases of diskospondylitis in dogs from 1997 through 2010. Signalment, clinical signs, MRI characteristics, and results of bacteriologic cultures of urine, blood, CSF, or intervertebral disk material were reviewed.
Results—On T2-weighted sequences, vertebral endplates were most often of mixed signal intensity, whereas the vertebral body was hypointense. The intervertebral disk space was most often hyperintense on T2-weighted and short tau inversion recovery sequences and of mixed signal intensity on T1-weighted sequences. Paravertebral soft tissue hyperintensities were noted commonly on T2-weighted and short tau inversion recovery sequences. Heterogenous contrast enhancement of endplates and intervertebral disk spaces also occurred commonly, whereas contrast enhancement of vertebral bodies and paravertebral soft tissues was uncommon. Intramedullary spinal cord intensity was noted at 10 of 27 sites on T2-weighted sequences. Static spinal cord compression occurred in 17 of 23 dogs, and a significant direct correlation was found between the percentage of spinal cord compression and the patient neurologic score.
Conclusions and Clinical Relevance—Results suggested that diskospondylitis in dogs has a characteristic MRI appearance, and in some patients, MRI may aid in the identification of severe spinal cord compression, which could warrant surgical intervention.
Abstract
Objective—To evaluate transurethral cystoscopy and excretory urography for diagnosis of ectopic ureter in female dogs and identify concurrent urogenital abnormalities.
Design—Retrospective study.
Animals—25 female dogs.
Procedure—Medical records of female dogs that underwent transurethral cystoscopy, excretory urography, and ventral cystotomy were reviewed for signalment, history, physical examination findings, results of bacteriologic culture of urine, and surgical findings. Videotapes of transurethral cystoscopy and radiographic studies were reviewed systematically without knowledge of surgical findings.
Results—Ectopic ureters were diagnosed in 24 of 25 (96%) of the dogs, bilaterally in 22 of 24 (91.6%) dogs. Cystoscopic evaluation yielded a correct diagnosis in all dogs when results of ventral cystotomy were used as the diagnostic standard. Cystoscopic evaluation identified a terminal ureteral opening for all ureters. Urethral fenestrations, troughs, striping, and tenting were identified. Abnormalities of the vestibule were identified in all examinations available for review (24/25). The paramesonephric septal remnant and its association with ectopic ureters were identified and characterized by cystoscopy. Radiographic findings were discordant with surgical findings and correctly identified 36 of 46 (78.2%) ectopic ureters and 2 of 4 normal ureters. Hydroureter and renal abnormalities were associated with distal urethral ectopic ureters on radiographic evaluations.
Conclusions and Clinical Relevance—Transurethral cystoscopy was accurate and minimally invasive for identification and classification of ectopic ureters in dogs. Contrast radiography had limitations in diagnosis of ectopic ureters. Cystoscopic findings and associated vaginal and vestibular abnormalities support abnormal embryologic development in the pathogenesis of ectopic ureters. (J Am Vet Med Assoc 2003;223:475–481)
Abstract
Objective
To describe the use of non–contrast-enhanced CT to identify deep digital flexor (DDF) tendinopathy in horses with lameness attributed to pain in regions distal to the metatarsophalangeal or metacarpophalangeal joints.
DESIGN
Retrospective case series.
ANIMALS
28 client-owned horses.
PROCEDURES
Medical records were searched to identify horses that underwent non–contrast-enhanced CT with or without high-field MRI as part of an evaluation for lameness localized to areas distal to the metacarpophalangeal or metatarsophalangeal joint in ≥ 1 limb. Horses were included in the study if they had ≥ 1 DDF tendon lesion (DDF tendinopathy) identified. Signalment, lameness examination findings and response to perineural anesthesia, imaging modality, anesthetic agents and duration of anesthesia, and imaging findings were recorded. Data were summarized descriptively.
RESULTS
Bilateral imaging was performed for all horses, irrespective of unilateral or bilateral lameness. Nine of 28 horses underwent both CT and MRI, and all DDF tendon lesions identified by one modality were identified by the other. Of 48 limbs with DDF tendinopathy, 46 (96%) had core lesions and 35 (73%) had dorsal border irregularities. Median anesthesia time for CT and CT followed by MRI was 15 and 110 minutes, respectively.
CONCLUSIONS AND CLINICAL RELEVANCE
Results suggested that non–contrast-enhanced CT was useful for identifying DDF tendinopathy in horses with lameness localized to the phalangeal regions, and this was supported by consistency of findings in a subset of horses that underwent MRI. Further research is needed to confirm these results.
Abstract
Objective—To determine maximum extrarenal plasma clearance of technetium-99m-mercaptoacetyltriglycine (99mTc–MAG3) and maximum extrarenal hepatic uptake of 99mTc–MAG3 in cats.
Animals—6 clinically normal adult cats.
Procedure—Simultaneously, baseline plasma clearance and camera-based uptake of 99mTc–MAG3 were determined in anesthetized cats. Double exponential curves were fitted to plasma clearance data. Injected dose was divided by area under the curve and body weight to determine 99mTc–MAG3 clearance. Regions of interest were drawn around kidneys and liver, and percentage dose uptake was determined 1 to 3 minutes after injection. After bilateral nephrectomy, simultaneous extrarenal plasma clearance and camera- based hepatic uptake of 99mTc–MAG3 were evaluated in each cat.
Results—Mean ± SD baseline plasma clearance and extrarenal clearance were 5.29 ± 0.77 and 0.84 ± 0.47 mL/min/kg, respectively. Mean extrarenal clearance (as a percentage of baseline plasma clearance) was 16.06 ± 7.64%. For right, left, and both kidneys, mean percentage dose uptake was 9.42 ± 2.58, 9.37 ± 0.86, and 18.79 ± 2.47%, respectively. Mean hepatic percentage dose uptake before and after nephrectomy was 12.95 ± 0.93 and 21.47 ± 2.00%, respectively. Mean percentage change of hepatic uptake after nephrectomy was 166.89 ± 23.19%.
Conclusions and Clinical Relevance—In cats, extrarenal clearance of 99mTc–MAG3 is higher than that of other species; therefore, 99mTc–MAG3 is not useful for estimation of renal function in felids. Evaluation of renal function in cats may be more accurate via camera- based versus plasma clearance-based methods because camera-based studies can discriminate specific organs. (Am J Vet Res 2003;64:1076–1080)