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in Journal of the American Veterinary Medical Association
in Journal of the American Veterinary Medical Association

Abstract

Objective—To evaluate expression of cyclooxygenase (COX)-1 and COX-2 in the cornea, eyelid, and third eyelid of healthy horses and those affected with squamous cell carcinoma (SCC) by use of immunohistochemical techniques.

Animals—15 horses with SCC involving ocular tissues and 5 unaffected control horses.

Procedures—SCC-affected tissues were obtained from the cornea (n = 5 horses), eyelid (5), and third eyelid (5). Site-matched control tissues were obtained from 5 horses unaffected with SCC. Tissue sections of affected and control cornea, eyelid, and third eyelid were stained immunohistochemically for COX-1 and COX-2 via standard techniques. Stain uptake was quantified by use of computer-assisted image analysis of digital photomicrographs.

Results—Immunoreactivity for both COX-1 and COX-2 was significantly greater in equine corneas with SCC than in control corneas. No significant differences in COX-1 or COX-2 immunoreactivity were detected in eyelid and third-eyelid SCC, compared with site-matched control tissues.

Conclusions and Clinical Relevance—Immunoreactivity for COX-1 and COX-2 is high in equine corneal SCC, possibly indicating that COX plays a role in oncogenesis or progression of this tumor type at this site. Pharmacologic inhibition of COX may represent a useful adjunctive treatment for corneal SCC in horses.

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in American Journal of Veterinary Research

Abstract

Objective—To determine results of diagnostic testing, including detection of nasal or frontal sinus fungal plaques, in dogs with nasal aspergillosis.

Design—Retrospective case series.

Animals—46 dogs with nasal aspergillosis.

Procedures—Medical records were reviewed for information on computed tomographic findings; rhinoscopic findings, including whether fungal plaques were seen in the nasal cavity; results of frontal sinus trephination and sinuscopy, including whether fungal plaques were seen in the frontal sinus; and results of histologic examination of biopsy specimens.

Results—In 38 (83%) dogs, fungal plaques were seen in the nasal cavity during rhinoscopy, whereas in the remaining 8 (17%), fungal plaques were not seen in the nasal cavity but were seen in the frontal sinus. Duration of clinical signs, proportions of dogs in which the referring veterinarian had performed a nasal examination prior to referral, proportions of dogs with computed tomographic evidence of nasal cavity cavitation or sinus involvement, and proportions of dogs with rhinoscopic evidence of destructive rhinitis were not significantly different between dogs with nasal fungal plaques and dogs with fungal plaques only in the frontal sinus.

Conclusions and Clinical Relevance—Results confirm that frontal sinus involvement is common in dogs with nasal aspergillosis and suggest that frontal sinus trephination and sinuscopy may aid in the diagnosis of aspergillosis in dogs, particularly dogs with rhinoscopic evidence of destructive rhinitis and computed tomographic evidence of sinus involvement that lack detectable fungal plaques in the nasal cavity.

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in Journal of the American Veterinary Medical Association

Abstract

Objective—To test the effects of bone diameter and eccentric loading on fatigue life of 2.7-mm-diameter cortical bone screws used for locking a 6-mm-diameter interlocking nail.

Sample Population—Eighteen 2.7-mm-diameter cortical bone screws.

Procedure—A simulated bone model with aluminum tubing and a 6-mm-diameter interlocking nail was used to load screws in cyclic 3-point bending. Group 1 included 6 screws that were centrally loaded within 19-mm-diameter aluminum tubing. Group 2 included 6 screws that were centrally loaded within 31.8-mmdiameter aluminum tubing. Group 3 included 6 screws that were eccentrically loaded (5.5 mm from center) within 31.8-mm-diameter aluminum tubing. The number of cycles until screw failure and the mode of failure were recorded.

Results—An increase in the diameter of the aluminum tubing from 19 to 31.8 mm resulted in a significant decrease in the number of cycles to failure (mean ± SD, 761,215 ± 239,853 to 16,941 ± 2,829 cycles, respectively). Within 31.8-mm tubing, the number of cycles of failure of eccentrically loaded screws (43,068 ± 14,073 cycles) was significantly greater than that of centrally loaded screws (16,941 ± 2,829 cycles).

Conclusions and Clinical Relevance—Within a bone, locking screws are subjected to different loading conditions depending on location (diaphyseal vs metaphyseal). The fatigue life of a locking screw centrally loaded in the metaphyseal region of bone may be shorter than in the diaphysis. Eccentric loading of the locking screw in the metaphysis may help to improve its fatigue life. (Am J Vet Res 2003;64:569–573)

Full access
in American Journal of Veterinary Research

Abstract

OBJECTIVE To determine the effect of arthrotomy alone or in combination with osteotomy of the proximal portion of the tibia on blood delivery to the patellar tendon of dogs.

SAMPLE 24 canine cadavers.

PROCEDURES One hind limb from each cadaver was assigned to 1 of 4 treatment groups: medial arthrotomy (MA; MA group), lateral arthrotomy (LA; LA group), MA and LA with tibial tuberosity transposition (MALA group), and MA with tibial plateau leveling osteotomy (TPLO; TPLO group). The contralateral hind limb served as the control sample. Contrast solution (barium [33%], India ink [17%], and saline [0.9% NaCl] solution [50%]) was injected through an 8F catheter inserted in the caudal portion of the abdominal aorta. Limbs were radiographed to allow examination of vascular filling. The patella, patellar tendon, and tibial crest were harvested, radiographed to allow examination of tissue vascular filling, and fixed in 4% paraformaldehyde. Vessels perfused with contrast solution were counted in sections obtained from the proximal, middle, and distal regions of each patellar tendon.

RESULTS Vessel counts did not differ significantly among the 3 tendon regions. Compared with results for the control group, delivery of contrast solution to the patellar tendon was significantly decreased in the MALA and TPLO groups but was not changed in the MA or LA groups.

CONCLUSIONS AND CLINICAL RELEVANCE Results indicated that surgical procedures used to treat cranial cruciate injuries (ie, TPLO) and patellar luxation decreased blood delivery to the patellar tendon of canine cadavers, at least acutely.

Full access
in American Journal of Veterinary Research

Abstract

Objective—To compare blood glucose concentrations obtained using a point-of-care (POC) analyzer, 5 portable blood glucose meters (PBGM), and a color reagent test strip with concentrations obtained using a reference method, and to compare glucose concentrations obtained using fresh blood samples in the PBGM with concentrations obtained using blood anticoagulated with lithium heparin.

Design—Case series.

Sample Population—110 blood samples from 34 dogs; glucose concentration of the samples ranged from 41 to 596 mg/dl.

Procedure—Logistic regression was used to compare blood glucose concentrations obtained with the various devices with reference method concentrations. Ease of use was evaluated subjectively. Percentage of times a clinical decision would have been altered if results of each of these methods had been used, rather than results of the reference method, was calculated.

Results—For 3 of the PBGM, blood glucose concentrations obtained with fresh blood were not significantly different from concentrations obtained with blood samples anticoagulated with lithium heparin. None of the devices provided results statistically equivalent to results of the reference method, but the POC analyzer was more accurate than the others. For some samples, reliance on results of the PBGM or the color test strip would have resulted in erroneous clinical decisions.

Conclusions and Clinical Relevance—Although commercially available PBGM and color test strips provided blood glucose concentrations reasonably close to those obtained with reference methods, some devices were more accurate than others. Use of results from these devices could lead to erroneous clinical decisions in some cases. ( J Am Vet Med Assoc 2000;216:198–202)

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in Journal of the American Veterinary Medical Association

Abstract

Objective

To evaluate efficacy of florfenicol in an induced model of infectious bovine keratoconjunctivitis, using a blinded randomized, controlled trial.

Animals

48 male Holstein calves, 2 to 4 months old.

Procedure

Moraxella bovis infection was induced in all calves. When corneal ulcers developed, each calf was assigned randomly to 1 of 3 treatment groups, using a block design determined by corneal ulcer size (day 0). Calves were treated with florfenicol (20 mg/kg of body weight, IM) on days 0 and 2 (IM group; n = 16). Calves of a second group received a single dose of florfenicol (40 mg/kg, SC) on day 0 (SC group; n = 16). The third group of calves was not treated (control group; n = 16). Corneal ulcers were photographed, and each calf was assessed for 30 days after treatment for 10 clinical signs of infection. Corneal ulcer surface areas were measured, and clinical scores were calculated. Ocular secretions for microbiologic culture were obtained weekly from each eye.

Results

A Cox regression model indicated that, after adjustment for initial ulcer size, healing rates were 6.2 and 4.8 times greater in calves of the IM and SC groups, respectively, compared with the control group. Clinical scores and surface area measurements for treatment groups were significantly smaller than those for controls during posttreatment weeks 1 through 4. From day 8 through day 29, M bovis was isolated from ocular secretions of 14 of 16 control calves and 1 of 32 treated calves.

Conclusions and Clinical Relevance

Parenterally administered florfenicol reduces corneal ulcer healing time, lessens clinical severity, and reduces the amount of bacterial shedding from calves infected with M bovis. (Am J Vet Res 1999;60:960-964)

Free access
in American Journal of Veterinary Research

Summary

Of 1,345 cats admitted for orchiectomy during a 10-year period, 23 (1.7%) were cryptorchid and 2(0.1%) were monorchid. Persian cats were overrepresented in the cryptorchid population (P = 0.01). Cats were more likely to be unilaterally than bilaterally cryptorchid (P = 0.01). A predisposition for location of undescended testes (abdominal vs inguinal or right vs left side) was not identified in unilateral cryptorchids. All bilateral cryptorchids had abdominally located testes. The most common surgical approaches used for orchiectomy of cryptorchid cats were a caudal ventral midline incision for inguinal testes and a caudal ventral midline celiotomy for abdominal testes.

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in Journal of the American Veterinary Medical Association