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Mechanical properties of various suture materials and placement patterns tested with surrogate in vitro model constructs simulating laryngeal advancement tie-forward procedures in horses Texto completo
2014
Santos, Marcos P. | Gutierrez-Nibeyro, Santiago D. | Horn, Gavin P. | Johnson, Amy J. | Stewart, Matthew C. | Schaeffer, David J.
Objective- To compare the mechanical properties of laryngeal tie-forward (LTF) surrogate constructs prepared with steel fixtures and No. 5 braided polyester or braided polyethylene by use of a standard or a modified suture placement technique. Sample- 32 LTF surrogate constructs. Procedures- Surrogate constructs were prepared with steel fixtures and sutures (polyester or polyethylene) by use of a standard or modified suture placement technique. Constructs underwent single-load-to-failure testing. Maximal load at failure, elongation at failure, stiffness, and suture breakage sites were compared among constructs prepared with polyester sutures by means of the standard (n = 10) or modified (10) technique and those prepared with polyethylene sutures with the standard (6) or modified (6) technique. Results- Polyethylene suture constructs had higher stiffness, higher load at failure, and lower elongation at failure than did polyester suture constructs. Constructs prepared with the modified technique had higher load at failure than did those prepared with the standard technique for both suture materials. All sutures broke at the knot in constructs prepared with the standard technique. Sutures broke at a location away from the knot in 13 of 16 constructs prepared with the modified technique (3 such constructs with polyethylene sutures broke at the knot). Conclusions and Clinical Relevance- Results suggested LTF surrogate constructs prepared with polyethylene sutures or the modified technique were stronger than those prepared with polyester sutures or the standard technique.
Mostrar más [+] Menos [-]Evaluation of a single intra-articular injection of autologous protein solution for treatment of osteoarthritis in horses Texto completo
2014
Bertone, Alicia L. | Ishihara, Akikazu | Zekas, Lisa J. | Wellman, Maxey L. | Lewis, Katharine B. | Schwarze, Rebecca A. | Barnaba, Andrea R. | Schmall, Michael L. | Kanter, Peter M. | Genovese, Ron L.
Objective-To evaluate intra-articular autologous protein solution (APS) for the treatment of osteoarthritis in horses. Animals-40 client-owned horses with naturally occuring osteoarthritis. Procedures-APS was generated from a dual-device system that concentrated plasma and WBC proteins and enriched platelet growth factors. Horses were randomly assigned to receive an intra-articular injection of 5 mL of saline (0.9% NaCl) solution (n = 20) or APS (20), exercised on a treadmill, and evaluated on the basis of lameness grades, kinetic gait analysis, joint circumference, and range of motion for 14 days. Horses that received saline solution were administered APS at termination of the study, and clients scored horses for lameness and discomfort before, 12 weeks after, and 52 weeks after the APS injection. Results-The APS group had significant improvements in lameness grade, asymmetry indices of vertical peak force, and range of joint motion by 14 days, compared with baseline or control group values. No adverse effects associated with APS treatment were evident. Clients assessed lameness and comfort as improved at 12 and 52 weeks. The APS had greater likelihood (OR, 4.3 to 30.0) of a therapeutic response in horses with a lameness score < 4, < 10% vertical force asymmetry, or absence of marked osteophyte formation, subchondral sclerosis, or joint space narrowing. Concentration of interleukin-1 receptor antagonist in APS was 5.8 times that in blood. Conclusions and Clinical Relevance-Intra-articular administration of APS can be considered an effective treatment option for equine osteoarthritis, with the potential for disease-modifying effects.
Mostrar más [+] Menos [-]Abdominal anatomic features and reference values determined by use of ultrasonography in healthy common rats (Rattus norvegicus) Texto completo
2014
Banzato, Tommaso | Bellini, Luca | Contiero, Barbara | Martin, Andrea | Balikçi, Sema | Zotti, Alessandro
Objective-To determine ultrasonographic features and reference values of the anatomy of the abdomen of common rats (Rattus norvegicus). Animals-20 adult male and 20 adult female rats. Procedures-A complete abdominal ultrasonographic examination was performed with the rats sedated. The cadavers of 4 rats were used for anatomic comparisons. Two cadavers were dissected and 2 cadavers were frozen and then cross-sectioned by use of an electric bandsaw. Slices were cleaned with water and photographed on each side. Correlations between variables were determined. Results-The ultrasonographic anatomy of the abdomen was determined, including measurements of the kidneys and adrenal glands and thickness of the walls of the stomach (saccus caecus, fundus, and pylorus), duodenum, and cecum. A significant positive correlation between kidney size and body weight was detected. The dorsoventral measurements of the left and right adrenal gland were significantly different, regardless of sex. Dorsoventral measurements of the right adrenal gland were significantly different between males and females. Conclusions and Clinical Relevance-The ultrasonographic images and data provided an atlas of the ultrasonographic anatomy of common rats that may be useful to veterinary radiologists, clinicians, and researchers.
Mostrar más [+] Menos [-]Pharmacokinetics of meloxicam administered orally to rabbits (Oryctolagus cuniculus) for 29 days Texto completo
2014
Delk, Katie W. | Carpenter, James W. | KuKanich, Butch | Nietfeld, Jerome C. | Kholes, Micah
Objective-To determine the pharmacokinetics and safety of meloxicam in rabbits when administered orally for 29 days. Animals-6 healthy rabbits. Procedures-Meloxicam (1.0 mg/kg, PO, q 24 h) was administered to rabbits for 29 days. Blood was collected immediately before (time 0) and 2, 4, 6, 8, and 24 hours after drug administration on days 1, 8, 15, 22, and 29 to evaluate the pharmacokinetics of meloxicam. On day 30, an additional sample was collected 36 hours after treatment. Plasma meloxicam concentrations were quantified with liquid chromatography–mass spectrometry, and noncompartmental pharmacokinetic analysis was performed. Weekly plasma biochemical analyses were performed to evaluate any adverse physiologic effects. Rabbits were euthanatized for necropsy on day 31. Results-Mean +/- SD peak plasma concentrations of meloxicam after administration of doses 1, 8, 15, 22, and 29 were 0.67 +/- 0.19 μg/mL, 0.81 +/- 0.21 μg/mL, 1.00 +/- 0.31 μg/mL, 1.00 +/- 0.29 μg/mL, and 1.07 +/- 0.19 μg/mL, respectively; these concentrations did not differ significantly among doses 8 through 29. Results of plasma biochemical analyses were within reference ranges at all time points evaluated. Gross necropsy and histologic examination of tissues revealed no clinically relevant findings. Conclusions and Clinical Relevance-Plasma concentrations of meloxicam for rabbits in the present study were similar to those previously reported in rabbits that received 1. 0 mg of meloxicam/kg, PO every 24 hours, for 5 days. Results suggested that a dosage of 1. 0 mg/kg, PO, every 24 hours for up to 29 days may be safe for use in healthy rabbits.
Mostrar más [+] Menos [-]Effects of a dexmedetomidine constant rate infusion and atropine on changes in global perfusion variables induced by hemorrhage followed by volume replacement in isoflurane-anesthetized dogs Texto completo
2014
Candido, Thaisa D. | Teixeira-Neto, Francisco J. | Diniz, Miriely S. | Zanuzzo, Felipe S. | Teixeira, Lidia R. | Fantoni, Denise T.
Objective—To evaluate the effects of a dexmedetomidine constant rate infusion (CRI) and atropine on changes in global perfusion variables induced by hemorrhage and volume replacement (VR) in isoflurane-anesthetized dogs. Animals—8 adult dogs. Procedures—Each dog was anesthetized twice, with a 2-week interval between anesthetic sessions. Anesthesia was maintained with 1.3 times the minimum alveolar concentration of isoflurane with and without dexmedetomidine (1.6 μg/kg, IV bolus, followed by 2 μg/kg/h, CRI). Dogs were mechanically ventilated and received an atracurium neuromuscular blockade during both sessions. During anesthesia with isoflurane and dexmedetomidine, atropine was administered 30 minutes before baseline measurements were obtained. After baseline data were recorded, 30% of the total blood volume was progressively withdrawn and VR was achieved with an equal proportion of autologous blood. Results—Following hemorrhage, cardiac index, oxygen delivery index, and mixed-venous oxygen saturation were significantly decreased and the oxygen extraction ratio was significantly increased from baseline. The anaerobic threshold was not achieved during either anesthetic session. When dogs were anesthetized with isoflurane and dexmedetomidine, they had a significantly lower heart rate, cardiac index, and mixed-venous oxygen saturation during VR than they did when anesthetized with isoflurane alone. Plasma lactate concentration, mixed venous-to-arterial carbon dioxide difference, base excess, and anion gap were unaltered by hemorrhage and VR and did not differ between anesthetic sessions. Conclusions and Clinical Relevance—Results indicated that the use of a dexmedetomidine CRI combined with atropine in isoflurane-anesthetized dogs that underwent volume-controlled hemorrhage followed by VR did not compromise global perfusion sufficiently to result in anaerobic metabolism.
Mostrar más [+] Menos [-]In vitro evaluation of a novel fiducial marker for computed tomography and magnetic resonance imaging of soft tissues in small animals Texto completo
2014
Terry, Jesse L. | Milovancev, Milan | Nemanic, Sarah
Objective—To construct and optimize a fiducial marker suitable for both CT and MRI. Sample—Fiducial markers containing serial dilutions of iopamidol mixed with water. Procedures—IV tubing sets were infused with serial dilutions (0% to 100%; increments of 10%) of iopamidol. Tubing ends were sealed; additional seals were added to create an equilateral triangle. A reference point was created by placing a crimp in 1 side. Markers were fixed to a gelatin soft tissue–attenuating phantom and evaluated by use of CT and MRI. For CT, simple linear regression analysis was used to assess the relationship between the percentage of marker contrast medium and quantitative variables, including marker attenuation, attenuation changes in the phantom, and beam-hardening artifact length. A subjective grading scheme for artifact creation on CT images and marker visibility on MRI images was used. Measurements were obtained by investigators who were unaware of the contents of each marker. Results—Percentage of contrast medium in each marker was strongly correlated with marker attenuation (r2 = 0.96), artifact length (r2 = 0.765), and mean attenuation changes within the phantom (r2 = 0.826) for CT. Subjective CT scores indicated that concentrations of contrast medium > 50% resulted in excessive artifacts. Markers with concentrations of iopamidol > 50% had poor subjective MRI visibility scores. No artifacts were seen on MRI. Conclusions and Clinical Relevance—A marker containing a 10% solution of iodinated contrast medium mixed with water provided ideal contrast for both CT and MRI.
Mostrar más [+] Menos [-]Estimation of the population size of Canadian commercial poultry farms by log-linear capture-recapture analysis Texto completo
2014
El Allaki, Farouk | Christensen, Jette | Vallieres, Andre | Pare, Julie
The objective of this study was to estimate the population size of Canadian poultry farms in 3 subpopulations (British Columbia, Ontario, and Other) by poultry category. We used data for 2008 to 2011 from the Canadian Notifiable Avian Influenza (NAI) Surveillance System (CanNAISS). Log-linear capture-recapture models were applied to estimate the number of commercial chicken and turkey farms. The estimated size of farm populations was validated by comparing sizes to data provided by the Canadian poultry industry in 2007, which were assumed to be complete and exhaustive. Our results showed that the log-linear modelling approach was an appropriate tool to estimate the population size of Canadian commercial chicken and turkey farms. The 2007 farm population size for each poultry category was included in the 95% confidence intervals of the farm population size estimates. Log-linear capture-recapture modelling might be useful for estimating the number of farms using surveillance data when no comprehensive registry exists.
Mostrar más [+] Menos [-]Effects of staple size, tissue thickness, and precompression time on staple shape in side-to-side jejunocecal anastomosis in specimens obtained from healthy horses at an abattoir Texto completo
2014
Giusto, Gessica | Gandini, Marco | Amedeo, Stefano
Objective—To determine effects of staple size, precompression time, and tissue thickness on staple shape and tissue approximation in side-to-side jejunocecal anastomosis in equine specimens. Sample—Cecum, ileum, and jejunum specimens obtained from 18 healthy horses at an abattoir. Procedures—Specimens were allotted into 2 groups. Anastomoses were stapled with 4.8-or 3.8-mm staples. Precompression time was 15 seconds for both groups. Staple lines were cut into proximal, middle, and distal sections. Thickness of intestinal walls was measured with a calibrated tissue micrometer, photographs were obtained, and intestinal tissues were digested. An investigator measured staples and assessed the shape of staples on high-definition digital images. Number of optimally shaped staples and staple height were compared among sections and between groups. Results—Use of 4.8-mm staples resulted in poor approximation of tissues in the distal sections of anastomoses. The percentage of optimally shaped staples was 538 of 551 (97.6%) and 616 of 634 (97.2%) for 4.8- and 3.8-mm staples, respectively. The percentage of optimally shaped staples did not differ significantly between groups for the same sections. There was a lower percentage of optimally shaped staples in the distal sections than in the proximal and middle sections of each group. Mean staple height did not differ significantly among sections of each group. Conclusions and Clinical Relevance—Use of 3.8-mm staples with an adequate precompression time for jejunocecal anastomosis in horses resulted in proper staple shape. These findings could be used to improve the technique and outcome for stapled jejunocecal anastomoses in horses.
Mostrar más [+] Menos [-]Differentiation of canine adipose tissue–derived mesenchymal stem cells towards endothelial progenitor cells Texto completo
2014
Kang, Byung-Jae | Lee, Seung-Hoon | Kweon, Oh-Kyeong | Cho, Je-Yoel
Objective—To determine the differentiation of canine adipose tissue–derived mesenchymal stem cells (ASCs) into endothelial progenitor cells (EPCs). Animals—3 healthy adult Beagles. Procedures—Canine ASCs were isolated and cultured from adipose tissue, and endothelial differentiation was induced by culturing ASCs in differentiation medium. Morphological and immunophenotypic changes were monitored. Expression of endothelial-specific markers was analyzed by conventional and real-time RT-PCR assay. The in vitro and in vivo functional characteristics of the endothelial-like cells induced from canine ASCs were evaluated by use of an in vitro solubilized basement membrane tube assay, low-density lipoprotein uptake assay, and in vivo solubilized basement membrane plug assay. Results—After differentiation culture, the cells developed morphological changes, expressed EPC markers such as CD34 and vascular endothelial growth factor receptor 2, and revealed functional characteristics in vitro. Furthermore, the induced cells allowed vessel formation in solubilized basement membrane plugs in vivo. Conclusion and Clinical Relevance—Results indicated that canine ASCs developed EPC characteristics when stimulated by differentiation medium with growth factors. Thus, differentiated canine ASC-EPCs may have the potential to provide vascularization for constructs used in regenerative medicine strategies.
Mostrar más [+] Menos [-]Use of an inertial measurement unit to assess the effect of forelimb lameness on three-dimensional hoof orientation in horses at a walk and trot Texto completo
2014
Moorman, Valerie J. | Reiser, Raoul F II | Mahaffey, Christie A. | Peterson, Michael L. | Mcllwraith, C Wayne | Kawcak, Christopher E.
Objective—To determine intralimb orientation changes with an inertial measurement unit (IMU) in hooves of horses at a walk and trot after induction of weight-bearing single forelimb lameness and to determine whether hoof orientations are similar to baseline values following perineural anesthesia. Animals—6 clinically normal horses. Procedures—3-D hoof orientations were determined with an IMU mounted on the right forelimb hoof during baseline conditions, during 3 grades of lameness (induced by application of pressure to the sole), and after perineural anesthesia. Linear acceleration profiles were used to segment the stride into hoof breakover, stance, initial swing, terminal swing, and total swing phases. Intralimb data comparisons were made for each stride segment. A repeated-measures mixed-model ANOVA was used for data analysis. Results—Lameness resulted in significant changes in hoof orientation in all planes of rotation. A significant increase in external rotation and abduction and a significant decrease in sagittal plane rotation of the hoof were detected at hoof breakover during lameness conditions. For sagittal plane orientation data, the SDs determined following perineural anesthesia were higher than the SDs for baseline and lameness conditions. Conclusions and Clinical Relevance—Results of this study indicated the IMU could be used to detect 3-D hoof orientation changes following induction of mild lameness at a walk and trot. An increase in data variability for a sagittal orientation may be useful for assessment of local anesthesia for hooves. The IMU should be further evaluated for use in clinical evaluation of forelimb lameness in horses.
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