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Abstract

OBJECTIVE To determine the incidence of chyloabdomen diagnosis in cats and dogs and characterize and compare between species the corresponding clinical signs, clinicopathologic test results, and outcomes.

DESIGN Retrospective case series.

ANIMALS 36 cats and 17 dogs in which chyloabdomen was diagnosed at a veterinary teaching hospital between 1984 and 2014.

PROCEDURES Medical records were reviewed, and data retrieved included patient signalment; clinical signs at initial evaluation; results of physical examination, diagnostic tests, and imaging studies; and outcomes. Survival analyses, descriptive statistics, and comparisons between species were completed.

RESULTS The incidence of chyloabdomen at the veterinary teaching hospital during the study period was 2.0 cases/100,000 admissions for cats and 2.8 cases/100,000 admissions for dogs. The mean age at diagnosis of chyloabdomen in cats was 11.3 years, compared with 6.9 years in dogs. The most common clinical signs in dogs and cats combined were lethargy (39/51 [76%]) and anorexia (37/51 [73%]), but fewer (23/53 [43%]) had abdominal distention. Chylothorax was a common comorbidity (25/53 [47%]), with malignant neoplasia being the most common underlying diagnosis (24/53 [45%]). Survival analyses included 44 patients; median survival time from diagnosis of chyloabdomen was 31 days overall, 8 days for patients with malignant neoplasia, and 73 days for patients without neoplasia.

CONCLUSIONS AND CLINICAL RELEVANCE There were multiple causes of chyloabdomen in dogs and cats of the study, and outcome depended on underlying cause. Because of this and the rarity of chyloabdomen, a multicenter prospective study of disease progression, treatment response, and clinical outcome for dogs and cats with chyloabdomen is needed.

Restricted access
in Journal of the American Veterinary Medical Association

Abstract

Objective—To investigate activation of the mammalian target of rapamycin (mTOR) pathway and the antitumor effect of rapamycin in canine osteosarcoma cells.

Sample Population—3 established primary canine osteosarcoma cell lines generated from naturally developing tumors.

Procedures—Expression of total and phosphorylated mTOR and p70S6 kinase was assessed by use of western blot analysis in canine osteosarcoma cells with and without the addition of rapamycin. A clonogenic assay was performed to determine the surviving fraction of osteosarcoma cells at various concentrations of rapamycin.

Results—Total and phosphorylated mTOR and p70S6 kinase expression was evident in all 3 cell lines evaluated, which was indicative of activation of this pathway. Treatment with rapamycin resulted in a time-dependent decrease in phosphorylated mTOR expression and a lack of detectable phosphorylated p70S6 kinase. No detectable change in expression of total mTOR and total p70S6 kinase was identified after rapamycin treatment. The clonogenic assay revealed a significant dose-dependent decrease in the surviving fraction for all 3 cell lines when treated with rapamycin.

Conclusions and Clinical Relevance—These data indicated that mTOR and its downstream product are present and active in canine osteosarcoma cells. The pathway can be inhibited by rapamycin, and treatment of cells with rapamycin decreased the surviving tumor cell fraction. These data support the molecular basis for further investigation into the use of mTOR inhibitors as an antineoplastic approach for dogs with osteosarcoma.

Full access
in American Journal of Veterinary Research

Abstract

Objective—To investigate the activation of the AKT and mammalian target of rapamycin (mTOR) pathways and assess the inhibitory effects of rapamycin on those pathways in canine malignant melanoma cells.

Sample Population—3 established primary canine melanoma cell lines generated from naturally occurring tumors.

Procedures—Expressions of total and phosphorylated AKT, mTOR, and p70 ribosomal S6 kinase 1 (p70S6K) in canine melanoma cells that were or were not exposed to 10nM rapamycin were assessed via western blot analysis. Clonogenic assays were performed to determine the surviving fraction of melanoma cells after exposure to 0.1, 1, 10, or 100nM rapamycin.

Results—Expressions of total and phosphorylated AKT, mTOR, and p70S6K proteins were detected (ie, the AKT and mTOR pathways were activated) in all 3 cell lines. Rapamycin treatment resulted in decreases in phosphorylated mTOR expression and phosphorylated p70S6K expression but no change in phosphorylated AKT expression. Expression of total AKT, mTOR, and p70S6K persisted after rapamycin treatment. There was a significant dose-dependent decrease in surviving tumor cell fraction for each cell line following treatment with rapamycin.

Conclusions and Clinical Relevance—These data indicated that AKT and mTOR, as well as their downstream product p70S6K, are present and active in canine melanoma cells. Activation of the mTOR pathway can be inhibited by rapamycin; treatment of melanoma cells with rapamycin decreased the surviving tumor cell fraction. Use of mTOR inhibitors as antineoplastic treatments in dogs with melanoma warrants investigation. Furthermore, these data support the use of canine melanoma cells as a molecular model for melanoma in humans.

Full access
in American Journal of Veterinary Research

Abstract

Objective—To determine expression of microRNA (miRNA) in urinary bladder samples obtained from dogs with grossly normal urinary bladders, inflammatory bladder disease, or transitional cell carcinoma (TCC) and in cells of established canine TCC cell lines.

Sample—Samples of grossly normal bladders (n = 4) and bladders from dogs with inflammatory bladder disease (13) or TCC (18), and cells of 5 established canine TCC cell lines.

Procedures—Expression of 5 miRNAs (miR-34a, let-7c, miR-16, miR-103b, and miR-106b) that target p53, Rb, or Bcl-2 protein pathways was determined for bladder samples and cells via quantitative real-time PCR assay. Effects of cisplatin (5μM) on proliferation and miRNA expression of cells were determined.

Results—Expression of miR-34a and miR-106b was significantly higher in TCC samples than it was in samples of grossly normal bladders. Expression of miR-34a, miR-16, miR-103b, and miR-106b was higher in TCC samples than it was in bladder samples from dogs with inflammatory bladder disease. Cells of established canine TCC cell lines that had the lowest growth after cisplatin treatment had increased miR-34a expression after such treatment.

Conclusions and Clinical Relevance—Findings of this study indicated results of miRNA expression assays can be used to distinguish between samples of grossly normal bladders and bladders of dogs with inflammatory bladder disease or TCC. This finding may have clinical relevance because currently available diagnostic tests cannot be used to differentiate these tissues, and inflammatory bladder disease and TCC are both prevalent in dogs. Validation of miRNA expression assays as diagnostic tests may be warranted.

Full access
in American Journal of Veterinary Research

Abstract

Objective—To determine progression-free and overall survival times of cats with squamous cell carcinoma (SCC) of the nasal planum following treatment with a single fraction of strontium Sr 90 (90Sr).

Design—Retrospective case series.

Animals—49 cats with SCC of the nasal planum.

Procedures—Information including FIV infection status, diagnosis of SCC vs SCC in situ (ie, evidence that the tumor did or did not penetrate the epidermal basement membrane, respectively), 90Sr dose and number of probe applications, treatment-related response and complications, and recurrence of SCC and new lesion development was obtained from medical records. The relationships of these variables with calculated progression-free and overall survival times were assessed.

Results—Of 49 cats that underwent 90Sr plesiotherapy (median dose, 128 Gy), 48 (98%) had a response to treatment and 43 (88%) had a complete response. Median progression-free and overall survival times were 1,710 and 3,076 days, respectively. Treatment complications were infrequent (4 [8%] cats) and mild. Following treatment, the SCC recurrence rate was 20% (10/49 cats); 16 (33%) cats developed new lesions in other locations. Overall survival time was significantly longer for cats with a complete response to treatment than for those with a partial response. None of the other variables evaluated had a significant effect on progression-free or overall survival time.

Conclusions and Clinical Relevance—Treatment of cats with SCC of the nasal planum with a single fraction of 90Sr appeared to be effective and well tolerated. Initial response to treatment was predictive of overall survival time.

Restricted access
in Journal of the American Veterinary Medical Association

Abstract

Objective—To determine whether there was a decline in the percentage of dogs undergoing necropsies and whether there was substantial agreement or disagreement between clinical and pathologic diagnoses.

Design—Retrospective study.

Animals—623 dogs.

Procedure—Medical records of hospitalized dogs that died or were euthanatized and necropsied at a veterinary teaching hospital in 1989 and 1999 were reviewed. Clinical and pathologic diagnoses were recorded and compared.

Results—There was a significant decline in the necropsy rate of hospitalized dogs that died or were euthanatized in 1999, compared with 1989. In both 1989 and 1999, there was disagreement between the clinical and pathologic diagnoses in approximately a third of the cases.

Conclusions and Clinical Relevance—Despite improved diagnostic methods, the accuracy of diagnosis did not improve significantly in 1999, compared with 1989. Necropsy is the best method to assess overall diagnostic accuracy. Increased availability of teaching funds may promote efforts to have necropsies performed in veterinary teaching hospitals. ( J Am Vet Med Assoc 2004;224:403–406)

Restricted access
in Journal of the American Veterinary Medical Association

Abstract

Objective—To develop a computer-assisted image analysis procedure for quantitation of neovascularization in formalin-fixed paraffin-embedded specimens of thyroid gland tissue from dogs with and without thyroid gland neoplasia.

Sample Population—47 thyroid gland carcinomas, 8 thyroid gland adenomas, and 8 specimens of thyroid tissue from dogs without thyroid gland abnormalities (normal).

Procedure—Serial tissue sections were prepared and stained with antibodies against human CD31 or factor VIII-related antigen (factor VIII-rag). The areas of highest vascularity were identified in CD31- stained sections, and corresponding areas were then identified in factor VIII-rag-stained sections. Image analysis was used to calculate the total vascular density in each section, and neovascularization, expressed as a percentage, was determined as the absolute value of the total vascular density derived from factor VIII-rag-stained sections minus the vascular density derived from CD31-stained sections.

Results—Mean vascular density of thyroid gland carcinomas derived from CD31-stained sections was significantly greater than density derived from factor VIII-rag-stained sections. This incremental difference was presumed to represent degree of neovascularization. However, significant differences were not detected between vascular densities derived from CD31 and factor VIII-rag-stained sections for either normal thyroid gland tissue or thyroid gland adenomas. No significant correlations were found between vascular density in thyroid gland carcinomas and survival time following surgery.

Conclusion and Clinical Relevance—A computerassisted image analysis method was developed for quantifying neovascularization in thyroid gland tumors of dogs. This method may allow identification of dogs with tumors that are most likely to respond to treatment with novel antiangiogenesis agents. (Am J Vet Res 2002;63:363–369)

Full access
in American Journal of Veterinary Research

Abstract

Objective—To optimize the use of CT-guided modeling for the calculation of body surface area (BSA) in domestic rabbits (Oryctolagus cuniculus).

Animals—12 domestic rabbits.

Procedures—Adult rabbits (body weight, 1 to > 4 kg) that were client-owned animals undergoing CT for disease diagnosis or deceased laboratory animals donated from other research projects were scanned with a CT scanner. Images were transferred to a radiation therapy planning software program. Image slices were captured as contiguous slices at 100 kVp and 100 mA and processed to 0.1-cm-thick sections. The length of each contoured slice was summed to calculate a final BSA measurement. Nonlinear regression analysis was then used to derive an equation for the calculation of BSA in rabbits.

Results—The constant calculated by use of this method was 9.9 (range, 9.59 to 10). The R 2 for the goodness of fit was 0.9332. The equation that best described BSA as a function of body weight for domestic rabbits with this method was as follows: BSA = (9.9 × [body weight {in grams}]2/3)/10,000.

Conclusions and Clinical Relevance—The BSA calculated via the CT-guided method yielded results similar to those obtained with equations for other similarly sized mammals and verified the use of such equations for rabbits. Additionally, this technique can be used for species that lack equations for the accurate calculation of BSA.

Full access
in American Journal of Veterinary Research

Abstract

OBJECTIVE

To evaluate the use of transrectal ultrasonography (TRUS) for the assessment of prostatic tumors in dogs and to compare results for TRUS with results for other imaging modalities.

ANIMALS

10 client-owned male dogs.

PROCEDURES

Client-owned dogs identified with prostatic carcinoma were enrolled. Fluoroscopy, transabdominal ultrasonography (TAUS), TRUS, and MRI were performed on all dogs. Tumor measurements, urethral penetration (identification of abnormal tissue within the urethral lumen), and tumor extension into the urinary tract were recorded for all imaging modalities. Agreement between results for MRI (considered the criterion-referenced standard) and results for other modalities were compared.

RESULTS

Median body weight of the 10 dogs was 26.3 kg (range, 9.4 to 49.5 kg). No complications were encountered during or after TRUS. Significant moderate to good agreements (intraclass correlation coefficients, 0.60 to 0.86) among TAUS, TRUS, fluoroscopy, and MRI were identified for tumor length and height. Assessments of urethral penetration and tumor extension into the bladder with TRUS did not differ significantly from those made with MRI and were superior in terms of absolute agreement with MRI when compared with those for TAUS.

CONCLUSIONS AND CLINICAL RELEVANCE

TRUS was successfully and safely used to evaluate prostatic carcinoma in dogs. There was moderate to good agreement with MRI results for tumor height and length measurements, and TRUS was found to be superior to TAUS for some assessments. Transrectal ultrasonography can be considered an adjunctive imaging modality for the performance of prostatic interventional procedures or assessment of response to treatment.

Full access
in American Journal of Veterinary Research

Abstract

OBJECTIVE

To determine whether an acceptance and commitment training (ACT) program targeting reactions to difficult client interactions would reduce burden transfer, stress, and burnout among veterinary healthcare teams.

SAMPLE

Small animal veterinary hospital employees randomly assigned to participate in an ACT program (intervention group; n = 72) or to not undergo the training program (control group; 71).

PROCEDURES

The study was designed as a randomized, controlled, parallel-arms trial. All participants completed prestudy assessments of burden transfer, stress, and burnout. The ACT program consisted of 3 small-group–format educational sessions tailored to reducing reactivity to difficult veterinary client interactions; sessions were delivered via video teleconference. At the end of the educational sessions (posttest) and 1 month later (1-month follow-up), assessments of burden transfer, stress, and burnout were repeated, and participants in the intervention group provided ratings of program helpfulness and frequency of use for techniques taught in the program.

RESULTS

Participants receiving the program rated it as helpful and reported frequent use of program techniques. Relative to the control group, the intervention group showed significantly reduced burden transfer, stress, work-related burnout, and client-related burnout after completing the educational sessions. These improvements were maintained at the 1-month follow-up.

CLINICAL RELEVANCE

Findings support the usefulness of this program in reducing occupational distress in veterinary medicine. Future work is needed to examine whether it is similarly effective in formats that could be more broadly disseminated (eg, asynchronous, self-paced, independent learning).

Open access
in Journal of the American Veterinary Medical Association