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النتائج 161 - 170 من 864
Effect of treatment with a cationic antiviral compound on acute infection with bovine viral diarrhea virus
2013
newcomer, Benjamin W. | Marley, M Shonda | Galik, Patricia K. | Zhang, Yijing | Riddell, Kay P. | Boykin, David W. | Kumar, Arvind | Kuhnt, Leah A. | Gard, Julie A. | Givens, M Daniel
Bovine viral diarrhea virus (BVDV) is a widespread bovine pathogen capable of causing disease affecting multiple body systems. Previous studies have shown 2-(2-benzimidazolyl)-5-[4-(2-imidazolino)phenyl]furan dihydrochloride (DB772) effectively prevents BVDV infection in cell culture. The aim of this project was to assess the efficacy of DB772 for the prevention of acute BVDV infection. Four calves seronegative to BVDV were treated with DB772 and another 4 calves were treated with diluent only on the same dosing schedule. Each calf was subsequently challenged intranasally with BVDV. Virus was isolated consistently from untreated calves on days 4 to 8, while treated calves remained negative by virus isolation during this period. Azotemia was exhibited by all treated calves on day 4 resulting in the euthanasia of 1 calf on day 10 and the death of another on day 13. Virus was isolated from the 2 remaining treated calves on day 14 or 21. On day 21, both remaining treated calves and all 4 untreated calves had anti-BVDV antibody titers > 1:2048. This pilot study indicates that DB772 temporarily prevented acute disease due to BVDV, but carries a significant concern of renal toxicity.
اظهر المزيد [+] اقل [-]Effect of furosemide and high-dosage pimobendan administration on the renin-angiotensin-aldosterone system in dogs
2013
Ames, Marisa K. | Atkins, Clarke E. | Lantis, Andrea C. | Werre, Stephen R.
Objective-To determine whether a high dosage of pimobendan, when administered concurrently with moderate-dosage furosemide to healthy dogs, would activate the renin-angiotensin-aldosterone system (RAAS) more than furosemide alone. Animals-12 healthy dogs. Procedures-6 dogs received furosemide (2.0 mg/kg, PO, q 12 h) only, as an RAAS activator, for 10 days. The other 6 dogs received furosemide (2.0 mg/kg, PO, q 12 h) and pimobendan (0.6 mg/kg, PO, q 12 h) for 10 days. The effect of these drugs on the RAAS was determined by measurement of the aldosterone-to-creatinine ratio (A:C) in urine collected in the morning and evening of study days −2, −1, 1, 5, and 10. Results-Although there was an increase in the urine A:C during the study period in both groups, it was significant only for dogs that received both drugs. The urine A:C only differed significantly between groups on day 1, at which time A:C was greater in the group that received both drugs. Conclusions and Clinical Relevance-High-dosage pimobendan administration neither substantially suppressed nor potentiated the RAAS when administered with furosemide in healthy dogs.
اظهر المزيد [+] اقل [-]In vitro effects of meloxicam on metabolism in articular chondrocytes from dogs with naturally occurring osteoarthritis
2013
Budsberg, Steven C. | Stoker, Aaron M. | Johnston, Spencer A. | Liska, William | Reno, Lisa R. | Coock, James L.
Objective-To assess effects of in vitro meloxicam exposure on metabolism in articular chondrocytes from dogs with naturally occurring osteoarthritis Sample-Femoral head cartilage from 16 dogs undergoing total hip replacement Procedures-Articular cartilage samples were obtained. Tissue sulfated glycosaminoglycan (SGAG), collagen, and DNA concentrations were measured. Collagen, SGAG, chondroitin sulfate 846, NO, prostaglandin E2 (PGE2), and matrix metalloproteinase (MMP)-2, MMP-3, MMP-9, and MMP-13 concentrations in culture medium were analyzed. Aggrecan, collagen II, MMP-2, MMP-3, MMP-9, MMP-13, ADAM metallopeptidase with thrombospondin type 1 motif (ADAMTS)-4, ADAMTS-5, tissue inhibitor of metalloproteinase (TIMP)-1, TIMP-2, TIMP-3, interleukin-1β, tumor necrosis factor-α, cyclooxygenase-1, cyclooxygenase-2, and nducible nitric oxide synthase gene expression were evaluated. Comparisons between tissues cultured without (control) and with meloxicam at concentrations of 0.3, 3.0, and 30.0 μg/mL for up to 30 days were performed by means of repeated-measures analysis. Results-Meloxicam had no effect on chondrocyte SGAG, collagen, or DNA concentrations. Expression of ADAMTS-5 was significantly decreased in all groups on all days, compared with the day 0 value. On day 3, culture medium PGE2 concentrations were significantly lower in all meloxicam-treated groups, compared with values for controls, and values remained low. Culture medium MMP-3 concentrations were significantly lower on day 30 than on day 3 in all meloxicam-treated groups. Conclusions and Clinical Relevance-Results suggested that in vitro meloxicam treatment of osteoarthritic canine cartilage for up to 30 days did not induce matrix degradation or stimulate MMP production. Meloxicam lowered PGE2 release from this tissue, and effects on tissue chondrocyte content and matrix composition were neutral.
اظهر المزيد [+] اقل [-]Evaluation of serosal patch supplementation of surgical anastomoses in intestinal segments from canine cadavers
2013
Hansen, Lane A. | Monnet, Eric L.
Objective-To compare leakage and maximum intraluminal pressures of intestinal anastomoses with and without serosal patch supplementation in dogs. Sample-Healthy small intestine segments from cadavers of 2 dogs euthanized for reasons unrelated to the study. Procedures-12 enterectomy constructs were created by anastomosis of intestinal segments with a standard simple continuous suture pattern. Half of the constructs were randomly selected for additional serosal patch support. Leakage and maximum intraluminal pressures were measured in and compared between patch-supplemented and nonsupplemented constructs. Results-Mean +/- SD leakage pressure was significantly greater for the patch-supplemented anastomoses (81.8 +/- 6.7 mm Hg) than for the nonsupplemented anastomoses (28.0 +/- 6.7 mm Hg). Maximum intraluminal pressures were not significantly different between the groups. Conclusions and Clinical Relevance-Serosal patch–supplemented anastomoses were able to sustain a significantly higher pressure before leakage than were nonsupplemented anastomoses in intestinal specimens from canine cadavers. The serosal patch supplementation may protect against leakage immediately after enterectomy in dogs.
اظهر المزيد [+] اقل [-]Noninvasive measurements of body composition and body water via quantitative magnetic resonance, deuterium water, and dual-energy x-ray absorptiometry in awake and sedated dogs
2013
Zanghi, Brian M. | Cupp, Carolyn J. | Pan, Yuanlong | Tissot-Favre, Delphine G. | Milgram, Norton W. | Nagy, Tim R. | Dobson, Howard
Objective-To compare quantitative magnetic resonance (QMR), dual-energy x-ray absorptiometry (DXA), and deuterium oxide (D2O) methods for measurement of total body water (TBW), lean body mass (LBM), and fat mass (FM) in healthy dogs and to assess QMR accuracy. Animals-58 Beagles (9 months to 11.5 years old). Procedures-QMR scans were performed on awake dogs. A D2O tracer was administered (100 mg/kg, PO) immediately before dogs were sedated, which was followed by a second QMR or DXA scan. Jugular blood samples were collected before and 120 minutes after D2O administration. Results-TBW, LBM, and FM determined via QMR were not significantly different between awake or sedated dogs, and means differed by only 2.0%, 2.2%, and 4.3%, respectively. Compared with results for D2O dilution, QMR significantly underestimated TBW (10.2%), LBM (13.4%), and FM (15.4%). Similarly, DXA underestimated LBM (7.3%) and FM (8.4%). A significant relationship was detected between FM measured via D2O dilution and QMR (r2 > 0.89) or DXA (r2 > 0.88). Even though means of TBW and LBM differed significantly between D2O dilution and QMR or DXA, values were highly related (r2 > 0.92). Conclusions and Clinical Relevance-QMR was useful for determining body composition in dogs and can be used to safely and rapidly acquire accurate data without the need for sedation or anesthesia. These benefits can facilitate frequent scans, particularly in geriatric, extremely young, or ill pets. Compared with the D2O dilution method, QMR correction equations provided accurate assessment over a range of body compositions.
اظهر المزيد [+] اقل [-]Evaluation of matrix metalloproteinase-2 and -9 in the cerebrospinal fluid of dogs with intracranial tumors
2013
Mariani, Christopher L. | Boozer, Lindsay B. | Braxton, Alicia M. | Platt, Simon R. | Vernau, Karen M. | McDonnell, John J. | Guevar, Julien
Objective: To identify matrix metalloproteinase (MMP)-2 and -9 in CSF from dogs with intracranial tumors. Sample: CSF from 55 dogs with intracranial tumors and 37 control dogs. Procedures: Latent and active MMP-2 and -9 were identified by use of gelatin zymography. The presence of MMPs in the CSF of dogs with intracranial tumors was compared with control dogs that were clinically normal and with dogs that had idiopathic or cryptogenic epilepsy or peripheral vestibular disease. Relationships between MMP-9 and CSF cell counts and protein were also investigated. Results: Latent MMP-2 was found in CSF samples from all dogs, although active MMP-2 was not detected in any sample. Latent MMP-9 was detected in a subset of dogs with histologically documented intracranial tumors, including meningiomas (2/10), gliomas (3/10), pituitary tumors (1/2), choroid plexus tumors (5/6), and lymphoma (4/4), but was not detected in any control samples. Dogs with tumors were significantly more likely than those without to have detectable MMP-9 in the CSF, and the presence of MMP-9 was associated with higher CSF nucleated cell counts and protein concentration. Conclusions and Clinical Relevance: Latent MMP-9 was detected in most dogs with choroid plexus tumors or lymphoma but in a smaller percentage of dogs with meningiomas, gliomas, or pituitary tumors. Detection of MMP in CSF may prove useful as a marker of intracranial neoplasia or possibly to monitor response of tumors to therapeutic intervention.
اظهر المزيد [+] اقل [-]Comparison of a body-mounted inertial sensor system–based method with subjective evaluation for detection of lameness in horses
2013
Keegan, Kevin G. | Wilson, David A. | Kramer, Joanne | Reed, Shannon K. | Yonezawa, Yoshiharu | Maki, Hiromitchi | Pai, P Frank | Lopes, Marco A.F.
Objective: To compare data obtained with an inertial sensor system with results of subjective lameness examinations performed by 3 experienced equine veterinarians for evaluation of lameness in horses. Animals: 106 horses. Procedures: Horses were evaluated for lameness with a body-mounted inertial sensor system during trotting in a straight line and via subjective evaluation by 3 experienced equine practitioners who performed complete lameness examinations including lunging in a circle and limb flexion tests. Agreement among evaluators regarding results of subjective evaluations and correlations and agreements between various inertial sensor measures and results of subjective lameness evaluations were determined via calculation of Fleiss’ κ statistic, regression analysis, and calculation of 95% prediction intervals. Results: Evaluators agreed on classification of horses into 3 mutually exclusive lameness categories (right limb lameness severity greater than left limb lameness severity, left limb lameness severity greater than right limb lameness severity, or equal right and left limb lameness severity) for 58.8% (κ = 0.37) and 54.7% (κ = 0.31) of horses for forelimb and hind limb lameness, respectively. All inertial sensor measures for forelimb and hind limb lameness were positively and significantly correlated with results of subjective evaluations. Agreement between inertial sensors measures and results of subjective evaluations was fair to moderate for forelimb lameness and slight to fair for hind limb lameness. Conclusions and Clinical Relevance: Results of lameness evaluation of horses with an inertial sensor system and via subjective lameness examinations were significantly correlated but did not have strong agreement. Inertial sensor-based evaluation may augment but not replace subjective lameness examination of horses.
اظهر المزيد [+] اقل [-]Use of a real-time three-dimensional motion tracking system for measurement of intrafractional motion of the thoracic wall in dogs
2013
Mayer, Monique N. | Lanovaz, Joel L. | Smith, Michael J. | Sidhu, Narinder | Waldner, Cheryl L.
Objective: To measure respiratory motion of the thoracic wall region in dogs using a real-time motion tracking system and compare the amount of respiratory motion between dogs positioned with and without a vacuum-formable cushion. Animals: 8 healthy adult mixed-breed dogs (median weight, 23 kg). Procedures: Dogs were anesthetized and positioned in sternal and dorsal recumbency with and without a vacuum-formable cushion. Three-dimensional movement of anatomic landmarks was measured with a real-time motion capture system that tracked the locations of infrared light–emitting diodes attached externally to the dorsal or ventral and lateral aspects of the thoracic wall. Results: Dogs positioned in sternal recumbency had significantly less cranial-to-caudal and left-to-right respiratory motion at the lateral aspect of the thoracic wall, compared with dogs positioned in dorsal recumbency, whether or not a cushion was used. For dogs treated in sternal recumbency, use of a cushion significantly increased the peak displacement vector (overall movement in 3-D space) for 3 of 4 marker locations on the dorsal thoracic wall. As respiratory rate increased, respiratory motion at the lateral and ventral aspects of the thoracic wall decreased when data for all dogs in dorsal recumbency were evaluated together. Conclusions and Clinical Relevance: Associations between respiratory rate and respiratory motion suggested that the use of rapid, shallow ventilation may be beneficial for dogs undergoing highly conformal radiation treatment. These results provide a basis for further research on respiratory motion in anesthetized dogs.
اظهر المزيد [+] اقل [-]Expression of matrix metalloproteinases, their inhibitors, and lysyl oxidase in myocardial samples from dogs with end-stage systemic and cardiac diseases
2013
Fonfara, Sonja | Hetzel, Udo | Tew, Simon R. | Cripps, Peter | Dukes-McEwan, Joanna | Clegg, Peter D.
Objective: To compare the degree of mRNA expression for matrix metalloproteinases (MMPs), tissue inhibitors (TIMPs), and lysyl oxidase in myocardial samples from dogs with cardiac and systemic diseases and from healthy control dogs. Sample: Myocardial samples from the atria, ventricles, and septum of 8 control dogs, 6 dogs with systemic diseases, 4 dogs with dilated cardiomyopathy (DCM), and 5 dogs with other cardiac diseases. Procedures: Degrees of mRNA expression for MMP-1, -2, -3, -9, and -13; TIMP-1, -2, -3, and -4; and lysyl oxidase were measured via quantitative real-time PCR assay. Histologic examination of the hearts was performed to identify pathological changes. Results: In myocardial samples from control dogs, only TIMP-3 and TIMP-4 mRNA expression was detected, with a significantly higher degree in male versus female dogs. In dogs with systemic and cardiac diseases, all investigated markers were expressed, with a significantly higher degree of mRNA expression than in control dogs. Furthermore, the degree of expression for MMP-2, TIMP-1, and TIMP-2 was significantly higher in dogs with DCM than in dogs with systemic diseases and cardiac diseases other than DCM. Expression was generally greater in atrial than in ventricular tissue for MMP-2, MMP-13, and lysyl oxidase in samples from dogs with atrial fibrillation. Conclusions and Clinical Relevance: Degrees of myocardial MMP, TIMP, and lysyl oxidase mRNA expression were higher in dogs with cardiac and systemic diseases than in healthy dogs, suggesting that expression of these markers is a nonspecific consequence of end-stage diseases. Selective differences in the expression of some markers may reflect specific pathogenic mechanisms and may play a role in disease progression, morbidity and mortality rates, and treatment response.
اظهر المزيد [+] اقل [-]Distribution of 2-deoxy-2-fluoro-d-glucose in the coelom of healthy bald eagles (Haliaeetus leucocephalus)
2013
Jones, Michael P. | Morandi, Federica | Wall, Jonathan S. | Long, Misty J. | Stuckey, Alan C. | LeBlanc, Amy K.
Objective: To determine 2-deoxy-2-fluoro (fluorine 18)-d-glucose (18FDG) biodistribution in the coelom of bald eagles (Haliaeetus leucocephalus). Animals: 8 healthy adult bald eagles. Procedures: For each eagle, whole-body transmission noncontrast CT, 60-minute dynamic positron emission tomography (PET) of the celomic cavity (immediately after 18FDG injection), whole-body static PET 60 minutes after 18FDG injection, and whole-body contrast CT with iohexol were performed. After reconstruction, images were analyzed. Regions of interest were drawn over the ventricular myocardium, liver, spleen, proventriculus, cloaca, kidneys, and lungs on dynamic and static PET images. Standardized uptake values were calculated. Results: Kidneys had the most intense 18FDG uptake, followed by cloaca and intestinal tract; liver activity was mild and slightly more intense than that of the spleen; proventricular activity was always present, whereas little to no activity was identified in the wall of the ventriculus. Activity in the myocardium was present in all birds but varied in intensity among birds. The lungs had no visibly discernible activity. Mean ± SD standardized uptake values calculated with representative regions of interest at 60 minutes were as follows: myocardium, 1. 6 ± 0.2 (transverse plane) and 1.3 ± 0.3 (sagittal plane); liver, 1.1 ± 0.1; spleen, 0.9 ± 0.1; proventriculus, 1.0 ± 0.1; cloaca, 4.4 ± 2.7; right kidney, 17.3 ± 1.0; left kidney, 17.6 ± 0.3; and right and left lungs (each), 0.3 ± 0.02. Conclusions and Clinical Relevance: The study established the biodistribution of 18FDG in adult eagles, providing a baseline for clinical investigation and future research.
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