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121.
This report describes 2 cases of spontaneous aortic dissecting hematoma in young Border Collie and Border Collie crossbred dogs. Histology was performed in one of the cases involving an unusual splitting of the elastin present within the wall of the aorta, consistent with elastin dysplasia as described in Marfan syndrome in humans. The first case involved a young purebred Border Collie that died suddenly and the second case involved a Border Collie crossbred dog that died after a 1-month history of seizures. Gross lesions included pericardial tamponade with dissection of the ascending aorta in the former case and thoracic cavity hemorrhage, mediastinal hematoma, and aortic dissection in the latter. Histologic lesions in the case of the Border Collie crossbred dog included a dissecting hematoma of the ascending aorta with elastin dysplasia and right axillary arterial intimal proliferation.  相似文献   
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An 8‐year‐old, intact female, mixed‐breed dog presented to the Oklahoma State University Boren Veterinary Medical Teaching Hospital for evaluation of progressive lameness and joint effusion of multiple joints. Physical examination revealed joint effusion of the elbow, hock, and stifle joints bilaterally, enlarged left axillary and right popliteal lymph nodes, a subcutaneous mass over the left elbow, and a subcutaneous mass involving the left second and third mammary glands. Cytologic examination of the mammary mass, enlarged lymph nodes, and joint fluid from most affected joints revealed a monomorphic population of loosely cohesive neoplastic epithelial cells. The patient was humanely euthanized, and subsequent necropsy with histopathologic examination revealed a complex mammary carcinoma with metastases to enlarged lymph nodes, subcutaneous tissue over the left elbow, and the synovium of multiple joints. Immunohistochemical stains were performed and showed diffusely positive pan cytokeratin, CK8/18, and CK19 staining in the neoplastic luminal epithelial cells of the mammary carcinoma, synovium, and lymph nodes, and showed diffusely positive vimentin staining of the myoepithelial cells. Myoepithelial calponin positivity was diffuse in the mammary mass and lymph nodes but minimal in the synovium. Only the mammary mass showed p63 positivity. Metastatic mammary neoplasia is relatively common in dogs; however, metastasis to the synovium has only been reported once previously in the literature. This is the first case utilizing immunohistochemistry for confirmation and characterization of metastases.  相似文献   
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Background: Many in‐house tests for the diagnosis of feline immunodeficiency virus (FIV) and feline leukemia virus (FeLV) infection are licensed for use in veterinary practice. A new test with unknown performance has recently appeared on the market. Objectives: The aims of this study were to define the efficacy of a new in‐clinic test system, the Anigen Rapid FIV Ab/FeLV Ag Test, and to compare it with the current leading in‐clinic test, the SNAP Kombi Plus FeLV Antigen/FIB Antibody Test. Methods: Three‐hundred serum samples from randomly selected healthy and diseased cats presented to the Clinic of Small Animal Medicine at Ludwig Maximilian University were tested using both the Anigen Rapid Test and the SNAP Kombi Plus Test. Diagnostic sensitivity, specificity, and positive and negative predictive values were calculated for both tests using Western blot as the gold standard for verification of FIV infection and PCR as the gold standard for FeLV infection. Results: The presence of antibodies against FIV was confirmed by Western blot in 9/300 samples (prevalence 3%). FeLV DNA was detected by PCR in 15/300 samples (prevalence 5%). For FIV infection the Anigen Rapid Test had a sensitivity of 88.9%, specificity of 99.7%, positive predictive value of 88.9%, and negative predictive value of 99.7%. For FeLV infection, the Anigen Rapid Test had a sensitivity of 40.0%, specificity of 100%, positive predictive value of 100%, and negative predictive value of 96.9%. Diagnostic accuracy was similar to that of the SNAP Kombi Plus Test. Conclusion: The new Anigen Rapid FIV Ab/FeLV Ag Test performed very well and can be recommended for use in veterinary practice.  相似文献   
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Background: Central nervous system (CNS) manifestations of hypothyroidism have been associated with cerebrovascular complications. Reports of cerebrospinal fluid (CSF) abnormalities are rare in hypothyroid dogs. Objective: The aim of this study was to determine if chronic hypothyroidism causes blood–brain‐barrier (BBB) abnormalities that are detectable using indirect CSF biomarkers. Methods: The study included 18 normal, euthyroid, female mixed‐breed dogs. Hypothyroidism was induced by 131iodine administration in 9 dogs; 9 served as untreated controls. Evaluations included physical and neurologic examination, complete CSF analysis, serum and CSF protein electrophoresis, measurement of plasma vascular endothelial growth factor (VEGF) and serum S‐100B concentrations, and calculation of CSF albumin quota (AQ) and were conducted at baseline and 6, 12, and 18 months after induction of hypothyroidism. Data were analyzed using repeated measures ANOVA. Results: At baseline, differences between groups were not detected for any variable. Throughout the study, controls dogs remained free of neurologic disease and had test variables that remained within reference intervals. Two hypothyroid dogs developed CNS signs during the study, and evidence of cerebrovascular disease was found at necropsy. At 12 and 18 months, the CSF total protein, VEGF, S‐100B, and fractional albumin concentrations, and AQ were significantly higher (P<.04) in hypothyroid dogs than controls. Among test variables assayed in serum or plasma, the only significant difference was a higher S‐100B concentration in hypothyroid dogs (P=.003) at 18 months. Conclusions: BBB integrity is disrupted in chronic hypothyroidism. Significant increases in CSF concentrations of VEGF and S100‐B in hypothyroid dogs indicate dysfunction in both endothelial and glial elements of the BBB.  相似文献   
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Magnetic resonance imaging (MRI) is a common test for dogs with suspected intradural spinal cord lesions, however studies on diagnostic performance for this test are lacking. Objectives of this multi‐institutional, retrospective, case‐control study were to estimate sensitivity and specificity of MRI for (1) distinguishing between histopathologically confirmed intradural spinal cord disease versus degenerative myelopathy in dogs, (2) categorizing intradural spinal cord diseases as neoplastic, inflammatory, or vascular; and (3) determining tumor type within the etiologic category of neoplasia. Additional aims were to (1) determine whether knowledge of clinical data affects sensitivity and specificity of MRI diagnoses; and (2) report interrater agreement for MRI classification of intradural spinal lesions. Cases were recruited from participating hospital databases over a 7‐year period. Three reviewers independently evaluated each MRI study prior to and after provision of clinical information. A total of 87 cases were sampled (17 degenerative myelopathy, 53 neoplasia, nine inflammatory, and eight vascular). Magnetic resonance imaging had excellent (>97.6%) sensitivity for diagnosis of intradural spinal cord lesions but specificity varied before and after provision of clinical data (68.6% vs. 82.4%, P = 0.023). Magnetic resonance imaging had good sensitivity (86.8%) and moderate specificity (64.7–72.5%) for diagnosing neoplasia. Sensitivity was lower for classifying inflammatory lesions but improved with provision of clinical data (48.1% vs. 81.5%, P = 0.015). Magnetic resonance imaging was insensitive for diagnosing vascular lesions (25.0%). Interrater agreement was very good for correctly diagnosing dogs with intradural lesions (? = 0.882–0.833), and good (? = 0.726–0.671) for diagnosing dogs with neoplasia.  相似文献   
130.
Since 2010, demand for non-GMO food products has grown dramatically. Two non-GMO labels dominate the market: USDA Organic and the Non-GMO Project Verified (the Project). However, the non-GMO status of Organic is not obvious from the label and many consumers are unaware of this. As sales of products carrying the Project’s non-GMO label have exploded, concern has increased among some Organic proponents that demand for non-GMO threatens the organic market. In response, both sides are seeking to build legitimacy and authority for their label by emphasizing the value of their standards for determining a food product’s non-GMO status within a GMO contaminated agrifood system. Drawing on in-depth interviews with key informants with knowledge of non-GMO standards and labels, we examine the knowledge systems, discourses and actors that proponents of the Project and USDA Organic privilege in their effort to legitimize their standards. Here, the Project emphasizes its application of technoscientific norms, especially thresholds and testing, which they argue provide the best means for preventing GMO contamination and helping consumers find (relative) non-GMO ‘purity’. In contrast, proponents of Organic favor a process standard that excludes GMOs, arguing that non-GMO ‘purity’ is unrealistic in today’s agrifood system that is widely contaminated by GMOs and where mandatory testing would unnecessarily harm organic producers. We conclude that tensions between the two groups are unlikely to be easily reconciled since these two distinct marketing labels rely on different knowledge and verification claims to vie for consumers and increase market share.  相似文献   
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