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Point shear wave elastography of the liver in healthy adult cats
2021
Park, Saechol | Choi, Jeongwoo | Kim, Kyeonga | Oh, Donghyun | Yoon, Junghee | Choi, Mincheol
OBJECTIVE To evaluate stiffness of the liver parenchyma in healthy adult cats by means of point shear wave elastography (PSWE). ANIMALS 18 client-owned adult (1- to 6-year-old) healthy cats. PROCEDURES Echogenicity and echotexture of the liver parenchyma were assessed by means of conventional B-mode ultrasonography. The shear wave velocity (Vs) of the right and left portions of the liver were measured by means of PSWE. RESULTS B-mode ultrasonography revealed no abnormalities in echotexture or echogenicity of the liver parenchyma in any cat. Mean (95% CI) Vs in the liver parenchyma was 1.46 m/s (1.36 to 1.55 m/s) for the right portion, 1.36 m/s (1.26 to 1.47 m/s) for the left portion, and 1.43 m/s (1.35 to 1.51 m/s) overall. The difference in mean Vs between the 2 portions of the liver was significant. No significant correlation was found between Vs and body weight or between Vs and the depth at which this variable was measured. CONCLUSIONS AND CLINICAL RELEVANCE Quantitative PSWE of the liver was feasible in healthy adult cats. The obtained values for Vs may be useful for interpretation of and comparison with values measured in cats with liver disease. Additional research is needed to explore the potential usefulness of PSWE for diagnostic purposes.
Afficher plus [+] Moins [-]Determination of the insertion position of implants for the cross-pin fixation of distal femoral physis fractures
2021
The cross-pin technique for the treatment of distal femoral physis fractures (specifically, Salter-Harris Type I fractures) was investigated using femurs collected from beagle cadavers. The pin was inserted from the medial surface of the femur at an inclination of approximately 30 to 45° relative to the long axis of the femur in the anteroposterior direction; the pin exit was set proximal to the origin of the long digital extensor tendon. Digital and radiographic images of the femur in the anteroposterior and lateral directions were obtained. In both types of images, the insertion angle of the pin relative to the long axis was measured. Results suggest that when inserting a pin proximal to the fracture line, the ideal position can be achieved by inclining the pin approximately 20° cranially relative to the long axis of the lateral direction of the femur, in addition to the previously described criteria.
Afficher plus [+] Moins [-]Development of a biologically immortalized equine stem cell line
2021
Nino-Fong, Rodolfo | Esparza Gonzlaez, Blanca P. | Rodriguez-Lecompte, Juan Carlos | Montelpare, William | McDuffee, Laurie
Bone repair in horses implies invasive surgeries and increased cost. Research on musculoskeletal disorders therapy in horses includes cell-based therapy with mesenchymal stromal cells (MSCs). Mesenchymal stromal cells can be obtained from bone marrow (BMMSCs). Unfortunately, BMMSCs have limited cell replication in vitro. The objective of this study was to develop a biologically immortalized equine stem cell line derived from bone marrow, with unlimited in-vitro proliferation and the ability to differentiate into bone cells. Equine BMMSCs were transfected and immortalized with human telomerase reverse transcriptase (hTERT) gene. Cell passages from equine immortal BMMSCs were characterized by the presence of stemness CD markers and expression of multi-potent differentiation genes (OCT-4, SOX2, and NANOG). Equine immortal BMMSCs were incubated in osteogenic medium and bone cell differentiation was determined by alkaline phosphatase and von Kossa staining, and osteogenic gene expression (osteocalcin, Runx2, and osterix). Telomerase activity was determined by telomeric repeat amplification technique. Results showed that equine immortal BMMSCs were able to replicate in-vitro up to passage 50 and maintain stem cell characteristics by the presence of CD90 and expression of multi-potent genes. Equine immortal BMMSCs were able to differentiate into bone cells, which was confirmed by the positive osteogenic staining and gene expression. Equine BMMSCs were successfully immortalized and maintained characteristics of stem cells and readily differentiated into osteogenic cells. Extending the life span of equine BMMSCs by transfection of the hTERT gene will revolutionize the clinical use of MSCs by making them available to orthopedic surgeons "off the shelf."
Afficher plus [+] Moins [-]Kinematic and kinetic analyses of the gait of horses wearing novel legwear for variably limiting extension of the metacarpophalangeal joint
2021
St. George, Lindsay B. | Pugliese, Brenna R. | Hobbs, Sarah J. | Brisbois, Abby L. | Sinclair, Jonathan K. | Kirker-Head, Carl A.
OBJECTIVE To investigate the effects of novel legwear designed to limit metacarpophalangeal joint (MCPJ) extension and redirect loading forces from the flexor apparatus through analyses of 2-D kinematic and kinetic data. ANIMALS 6 adult horses without musculoskeletal disease. PROCEDURES Horses were subjected to 4 treatments: control (no legwear), inactive legwear (unlimited legwear extension), and active legwear with mild (30°) and moderate (20°) legwear extension limitation. Two-dimensional kinematic data were collected for the right forelimb (FL) during walk and trot and from leading and trailing FLs during canter on a treadmill. Ground reaction force (GRF) data were collected from FLs during overground walk and trot. Peak MCPJ angle and angular velocity were calculated from kinematic data, and peak force and average loading rate were calculated from vertical GRF data during the stance phase of the gait. Interactions between gait and treatment were determined via ANOVA. RESULTS Interactions between gait and treatment for peak MCPJ angle were significant. Significant reductions in MCPJ angle were noted between the control treatment and legwear with moderate extension limitation for trot and canter (leading and trailing FL) and between inactive legwear and legwear with moderate extension limitation for trot and leading FL during canter. Interactions among peak MCPJ angular velocity, peak vertical GRF, and average loading rate of the vertical GRF showed nonsignificance. CONCLUSIONS AND CLINICAL RELEVANCE Significant reductions in MCPJ extension without significant alterations to peak vertical GRF suggested the legwear's ability to redistribute internal forces. Findings suggested that the legwear may be beneficial for horses rehabilitating from flexor apparatus injuries.
Afficher plus [+] Moins [-]Effect of epitendinous suture caliber on the tensile strength of repaired canine flexor tendons
2021
Duff, Daniel J. | Chang, Yi-Jen | Fisher, Matthew B. | Chambers, Aidan R. | Moore, George E.
OBJECTIVE To determine the effect of epitendinous suture (ES) caliber on the tensile strength of flexor tendon repairs in cadaveric specimens from dogs. SAMPLE 60 cadaveric superficial digital flexor tendons (SDFTs) from 30 skeletally mature dogs. PROCEDURES Specimens were randomly assigned to 5 suture caliber groups (n = 12 SDFTs/group). After sharp transection, SDFTs were repaired by placement of a simple continuous circumferential ES created with size-0, 2–0, 3–0, 4–0, or 5–0 polypropylene suture. Constructs were preloaded to 2 N and load tested to failure. Loads at yield, peak, and failure and mode of failure were compared among groups by statistical methods. RESULTS Yield, peak, and failure loads for SDFT repair constructs were positively correlated with ES caliber and did not differ between the size-0 and 2–0 groups on pairwise comparisons. Yield load was significantly greater for size-0, 2–0, and 3–0 groups than for the 4–0 and 5–0 groups. Peak and failure loads were significantly greater for the size-0 and 2–0 groups than for the remaining groups. Most size-0 (12/12), 2–0 (12/12), and 3–0 (10/12) group constructs failed because of ES pull-through; several constructs in the 4–0 group (5/12) and most in the 5–0 group (11/12) failed because of ES breakage. CONCLUSIONS AND CLINICAL RELEVANCE Results suggested size-0 and 2–0 sutures should be considered when placing an ES for flexor tendon repairs in dogs. However, in vivo studies are needed determine the effects of increasing ES caliber on clinical outcomes for dogs undergoing these procedures.
Afficher plus [+] Moins [-]Effect of recombinant equine interleukin-1β on function of equine endothelial colony-forming cells in vitro
2021
Reyner, Claudia L. | Winter, Randolph L. | Maneval, Kara L. | Boone, Lindsey H. | Wooldridge, Anne A.
OBJECTIVE To investigate the effects of recombinant equine IL-1β on function of equine endothelial colony-forming cells (ECFCs) in vitro. SAMPLE ECFCs derived from peripheral blood samples of 3 healthy adult geldings. PROCEDURES Function testing was performed to assess in vitro wound healing, tubule formation, cell adhesion, and uptake of 1,1′-dioctadecyl-3,3,3′,3′ tetramethylindocarbocyanine perchlorate–labeled acetylated low-density lipoprotein (DiI-Ac-LDL) by cultured ECFCs. Cell proliferation was determined by 2,3-bis-(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide assay. Effects on function test results of different concentrations and exposure times of recombinant equine IL-1β were assessed. RESULTS Challenge of cultured ECFCs with IL-1β for 48 hours inhibited tubule formation. Continuous challenge (54 hours) with IL-1β in the wound healing assay reduced gap closure. The IL-1β exposure did not significantly affect ECFC adhesion, DiI-Ac-LDL uptake, or ECFC proliferation. CONCLUSIONS AND CLINICAL RELEVANCE These results suggested a role for IL-1β in the inhibition of ECFC function in vitro. Functional changes in ECFCs following challenge with IL-1β did not appear to be due to changes in cell proliferative capacity. These findings have implications for designing microenvironments for and optimizing therapeutic effects of ECFCs used to treat ischemic diseases in horses.
Afficher plus [+] Moins [-]Evaluation of the expression of hexokinase 1, glucokinase, and insulin by canine insulinoma cells maintained in short-term culture
2021
Suwitheechon, Orn-usa | Schermerhorn, Thomas
OBJECTIVE To develop a technique for isolation and culture of canine insulinoma cells and assess expression of cellular hexokinases (glucokinase and hexokinase I) and expression and secretion of insulin from these cells in vitro. SAMPLE Pancreatic insulinomas and normal pancreatic tissue from 4 and 3 dogs, respectively. PROCEDURES Tissues were collected by surgical excision or at necropsy. Insulinoma cells from 2 dogs were cultured for up to 10 weeks with standard techniques; insulin synthesis in vitro was confirmed by immunohistochemical analysis of freshly prepared slides of cultured cells, and insulin secretion was assessed by measurement of insulin concentrations in culture medium with an ultrasensitive mouse insulin ELISA. Expression of cellular hexokinases in insulinomas and adjacent normal (nontumor) pancreatic tissue from the same dog (n = 3) was examined by quantitative reverse transcriptase PCR assay. RESULTS Insulinoma cells survived for up to 10 weeks but did not proliferate in culture. Insulin was detected in isolated cells and secreted into culture medium for up to 10 weeks. Both cellular hexokinases were expressed; glucokinase appeared to be overexpressed in insulinomas, compared with normal pancreatic tissue from the same dogs. CONCLUSIONS AND CLINICAL RELEVANCE Canine insulinomas expressed hexokinases responsible for glucose responsiveness. Insulinoma cells were successfully maintained in short-term culture; cultured cells remained functional for 10 weeks as evidenced by cellular insulin content and had detectable secretion of insulin into the culture medium for ≥ 5 weeks. Apparent glucokinase overexpression by insulinomas suggested a possible mechanism underlying excessive insulin release by these tumors.
Afficher plus [+] Moins [-]Beekeeping management practices in southwestern Quebec
2021
The growing number of honey bee colonies and beekeepers in Canada has led to a great diversity of beekeeping practices. All beekeeping operations, however, need to implement consistent management measures for the control of diseases. The objective of this study was to document the actual disease management practices of beekeeping productions in southwestern Quebec, Canada. A survey was conducted to describe management practices used by 15 beekeepers who own 1824 colonies in that area. Data were obtained by telephone interviews. When infectious diseases were suspected, beekeepers generally avoided using potentially toxic acaricides and chemical treatments associated with antimicrobial resistance and instead used preventive, physical or management methods, although laboratory diagnosis was rarely used. This study highlights the wide variety of operation sizes, activities, and disease management strategies among beekeepers in southwestern Quebec. It identifies the need to encourage the use of services available to them and to propose a standardized preventive medical approach for field veterinarians to avoid the spread of infectious diseases.
Afficher plus [+] Moins [-]Assessment of neutrophil function in canine cancer patients undergoing chemotherapy and correlation with neutrophil numbers
2021
Ravanbakhsh, Arefeh | Ahmed, Khawaja Ashfaque | MacDonald-Dickinson, Valerie | Fernandez, Nicole J. | Meachem, Melissa D. | Dickinson, Ryan M.
Decreased neutrophil function following administration of chemotherapy has been reported in dogs with lymphoma. The first objective of our study was to determine if neutrophil oxidative burst and phagocytic activity are affected by chemotherapy 7 to 10 days following initiation of treatment in dogs with lymphoma and non-lymphoma malignancies. The second objective was to determine if there is a correlation between neutrophil numbers and neutrophil function before or after initiation of chemotherapy. Flow cytometric assessment of neutrophil oxidative burst and phagocytosis following stimulation with Escherichia coli was performed in 9 dogs diagnosed with lymphoma and 17 non-lymphoma tumor-bearing dogs pre- and post-chemotherapy, as well as 14 tumor-free control dogs. Spearman rank correlation was performed to determine if blood neutrophil numbers and neutrophil function were significantly correlated. Lymphoma patients showed significantly reduced percentage neutrophil oxidative burst post-chemotherapy compared to healthy controls as well as compared to pre-chemotherapy values (P = 0.0022 and P = 0.0020, respectively). Lymphoma patients also exhibited significantly reduced neutrophil phagocytosis activity post-chemotherapy compared to controls and pre-chemotherapy values (P = 0.0016 and P = 0.014, respectively). Dogs with non-lymphoma malignancies also showed a significant decrease in both percentage oxidative burst and phagocytosis post-chemotherapy compared to pre-chemotherapy values (P = 0.00040 and P = 0.029, respectively). Neutrophil numbers and function were not significantly correlated. The results of the study suggest that chemotherapeutic treatment decreases neutrophil oxidative burst and phagocytic activity 7 to 10 days post-treatment in dogs with various malignancies. Furthermore, neutrophil numbers cannot be used to predict neutrophil function.
Afficher plus [+] Moins [-]Emergence of a novel recombinant USA/GBI29/2015-like strain of Seneca Valley virus in Guangdong Province, 2018
2021
Since June 2017, several outbreaks of a Seneca Valley virus (SVV) USA/GBI29/2015-like strain have emerged in pigs in China. In our study, we successfully isolated the SVV strain CH-GDZQ-2018, confirmed by immunofluorescence and Western blot assays. Phylogenetic and recombinant analyses showed that the USA/GBI29/2015-like CH-GDZQ-2018 strain was the result of recombination between epidemic strains local to Guangdong, showing that SVV has undergone evolution in China.
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