Search Results

Abstract

Objective—To evaluate use of computed tomography (CT) of the lungs, compared with conventional radiography, for detection of blebs and bullae associated with spontaneous pneumothorax in dogs.

Design—Retrospective case series.

Animals—12 dogs with spontaneous pneumothorax.

Procedure—Medical records were reviewed, and information was collected that included signalment, body weight, initial owner complaint, laboratory findings, radiographic findings, CT findings, medical and surgical treatment, histologic findings, complications, duration of hospitalization, and final outcome.

Results—Radiographs were excellent for identifying pneumothorax (sensitivity, 100%) but poor for identifying the underlying cause (bullae or blebs); these were identified in radiographs of only 2 of 12 dogs. Computed tomography allowed identification of bullae or blebs in 9 of 12 dogs. Ten of the 12 dogs were treated via surgery, and 17 affected lung lobes were identified. Four of the 17 affected lobes were identified via radiography. Thirteen of the 17 affected lobes were identified via CT; however, 1 lobe was incorrectly identified as the right caudal lobe instead of the right cranial lobe.

Conclusions and Clinical Relevance—Results suggested that CT is better than radiography for identifying the underlying causes of spontaneous pneumothorax.

Abstract

Objective—To determine whether oxidative stress could be induced in canine chondrocytes in vitro.

Sample—Chondrocytes obtained from healthy adult mixed-breed dogs.

Procedures—Harvested chondrocytes were maintained at 37°C with 5% CO₂ for 24 hours. To assess induction of oxidative stress, 2 stimuli were used: hydrogen peroxide and a combination of interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α). To determine the effect of hydrogen peroxide, a set of chondrocyte-seeded plates was incubated with control medium alone or hydrogen peroxide (100, 200, or 300μM) for 24 hours. For inhibition of oxidative stress, cells were incubated for 24 hours with N-acetylcysteine (NAC; 10mM) before exposure to hydrogen peroxide. Another set of chondrocyte-seeded plates was incubated with control medium alone or with IL-1β (10 ng/mL) and TNF-α (1 ng/mL) for 24 hours. Supernatants were obtained for measurement of prostaglandin E₂ production, and cell lysates were used for measurement of superoxide dismutase (SOD) activity and reduced-glutathione (GSH) concentration.

Results—Chondrocytes responded to the oxidative stressor hydrogen peroxide with a decrease in SOD activity and GSH concentration. Exposure to the antioxidant NAC caused an increase in SOD activity in hydrogen peroxide–stressed chondrocytes to a degree comparable with that in chondrocytes not exposed to hydrogen peroxide. Similarly, NAC exposure induced significant increases in GSH concentration. Activation with IL-1β and TNF-α also led to a decrease in SOD activity and increase in prostaglandin E₂ production.

Conclusions and Clinical Relevance—Canine chondrocytes responded to the oxidative stress caused by exposure to hydrogen peroxide and cytokines. Exposure to oxidative stress inducers could result in perturbation of chondrocyte and cartilage homeostasis and could contribute to the pathophysiology of osteoarthritis. Use of antioxidants, on the other hand, may be helpful in the treatment of arthritic dogs.

Abstract

Objective—To determine efficacy of a single intra-articular injection of an autologous platelet concentrate for treatment of osteoarthritis in dogs.

Design—Randomized, controlled, 2-center clinical trial.

Animals—20 client-owned dogs with osteoarthritis involving a single joint.

Procedures—Dogs were randomly assigned to a treatment or control group. In all dogs, severity of lameness and pain was scored by owners with the Hudson visual analog scale and the University of Pennsylvania Canine Brief Pain Inventory, respectively, and peak vertical force (PVF) was determined with a force platform. Dogs in the treatment group were then sedated, and a blood sample (55 mL) was obtained. Platelets were recovered by means of a point-of-use filter and injected intra-articularly within 30 minutes. Control dogs were sedated and given an intra-articular injection of saline (0.9% NaCl) solution. Assessments were repeated 12 weeks after injection of platelets or saline solution.

Results—Dogs weighed between 18.3 and 63.9 kg (40.3 and 140.6 lb) and ranged from 1.5 to 8 years old. For control dogs, lameness scores, pain scores, and PVF at week 12 were not significantly different from pretreatment values. In contrast, for dogs that received platelet injections, lameness scores (55% decrease in median score), pain scores (53% decrease in median score), and PVF (12% increase in mean PVF) were significantly improved after 12 weeks, compared with pretreatment values.

Conclusions and Clinical Relevance—Results suggested that a single intra-articular injection of autologous platelets resulted in significant improvements at 12 weeks in dogs with osteoarthritis involving a single joint.