Studies in humans have shown that the ubiquitin-proteasome pathway and the insulin-like growth factor axis are involved in carcinogenesis, thus, components of these systems might be useful as prognostic markers and constitute potential therapeutic targets. In veterinary medicine, only a few studies exist on this topic. Here, serum concentrations of 26S proteasome (26SP) and insulin-like growth factor-1 (IGF-1) were measured by canine enzyme-linked immunosorbent assay (ELISA) in 43 dogs suffering from malignant tumors and 21 clinically normal dogs (control group). Relationships with tumor size, survival time, body condition score (BCS), and tumor entity were assessed. The median 26SP concentration in the tumor group was non-significantly higher than in the control group. However, dogs with mammary carcinomas displayed significantly increased 26SP levels compared to the control group and dogs with tumor size less than 5 cm showed significantly increased 26SP concentrations compared to dogs with larger tumors and control dogs. 26SP concentrations were not correlated to survival time or BCS. No significant difference in IGF-1 levels was found between the tumor group and the control group; however, IGF-1 concentrations displayed a larger range of values in the tumor group. Dogs with tumors greater than 5 cm showed significantly higher IGF-1 levels than dogs with smaller tumors. The IGF-1 concentrations were positively correlated to survival time, but no correlation with BCS was found. Consequently, serum 26SP concentrations seem to be increased in some dogs suffering from malignant tumors, especially in dogs with mammary carcinoma and smaller tumors. Increased serum IGF-1 concentrations could be an indication of large tumors and a poor prognosis.

OBJECTIVE To quantitatively measure the amount of pressure induced at the calcaneus and cranial tibial surface of dogs by use of 2 cast configurations. ANIMALS 13 client- or student-owned dogs. PROCEDURES Pressure sensors were placed over the calcaneus and cranial tibial surface. Dogs then were fitted with a fiberglass cast on a pelvic limb extending from the digits to the stifle joint (tall cast). Pressure induced over the calcaneus and proximal edge of the cast at the level of the cranial tibial surface was simultaneously recorded during ambulation. Subsequently, the cast was shortened to end immediately proximal to the calcaneus (short cast), and data acquisition was repeated. Pressure at the level of the calcaneus and cranial tibial surface for both cast configurations was compared by use of paired t tests. RESULTS The short cast created significantly greater peak pressure at the level of the calcaneus (mean ± SD, 0.2 ± 0.07 MPa), compared with peak pressure created by the tall cast (0.1 ± 0.06 MPa). Mean pressure at the proximal cranial edge of the cast was significantly greater for the short cast (0.2 ± 0.06 MPa) than for the tall cast (0.04 ± 0.03 MPa). CONCLUSIONS AND CLINICAL RELEVANCE A cast extended to the level of the proximal portion of the tibia caused less pressure at the level of the calcaneus and the proximal cranial edge of the cast. Reducing the amount of pressure at these locations may minimize the potential for pressure sores and other soft tissue injuries.

OBJECTIVE To evaluate cardiopulmonary, sedative, and antinociceptive effects of dexmedetomidine combined with commonly administered opioids in dogs. ANIMALS 8 healthy Beagles. PROCEDURES Dogs were sedated by IM administration of each of 7 treatments. Treatments comprised dexmedetomidine (0.01 mg/kg; Dex) and the same dose of dexmedetomidine plus butorphanol (0.15 mg/kg; Dex-But), meperidine (5 mg/kg; Dex-Mep), methadone (0.5 mg/kg; Dex-Meth), morphine (0.5 mg/kg; Dex-Mor), nalbuphine (0.5 mg/kg; Dex-Nal), or tramadol (5 mg/kg; Dex-Tram). Cardiorespiratory and arterial blood gas variables and sedative and antinociceptive scores were measured before drug injection (time 0; baseline) and at 15-minute intervals for 120 minutes. RESULTS Heart rate was reduced at all time points after injection of Dex-But, Dex-Mep, Dex-Meth, and Dex-Mor treatments. There was a significant reduction of mean arterial blood pressure for Dex-But, Dex-Mep, and Dex-Mor treatments at all time points, compared with baseline. There was a significant decrease in respiratory rate, compared with the baseline value, for Dex, Dex-But, Dex-Meth, and Dex-Tram treatments from 15 to 120 minutes. A significant decrease in arterial blood pH was detected from baseline to 120 minutes for all treatments, with differences among Dex, Dex-Mep, and Dex-Mor. Reduction in Pao2 was greater for the Dex-Mep treatment than for the other treatments. The highest sedation scores were detected for Dex-Mep and Dex-Meth treatments. Antinociceptive effects were superior for Dex-But, Dex-Meth, Dex-Mor, and Dex-Nal treatments. CONCLUSIONS AND CLINICAL RELEVANCE Drug combinations caused similar cardiorespiratory changes, with greater sedative effects for Dex-Mep and Dex-Meth and superior antinociceptive effects for Dex-But, Dex-Meth, Dex-Mor, and Dex-Nal.

OBJECTIVE To create a bioactive synovium scaffold by infusing decellularized synovial-derived extracellular matrix (synECM) with synovial-derived mesenchymal stem cells (synMSCs). SAMPLE Synovium from the femoropatellar and medial femorotibial joints of equine cadavers. PROCEDURES The synMSCs were cultured in monolayer and not treated or cotransduced to enhance expression of green fluorescent protein (GFP) and human bone morphogenetic protein (BMP)-2. The synECM was decellularized with 0.1% peracetic acid and then seeded with synMSCs (0.5 × 10(6) cells/0.5 mL) by use of a 30% serum gradient. Samples were evaluated on days 0, 3, 7, and 14. Cell migration, differentiation, and distribution into the synECMs were determined by cell surface marker CD90, viability, histologic morphology, and fluorescence microscopy results and expression of GFP, BMP-2, hyaluronan (HA), and proteoglycan (PG). RESULTS At day 14, synMSCs were viable and had multiplied 2.5-fold in the synECMs. The synECMs seeded with synMSCs had a significant decrease in CD90 expression and significant increases in HA and PG expression. The synECMs seeded with synMSCs cotransduced with GFP, or BMP-2 had a significant increase in BMP-2 expression. CONCLUSIONS AND CLINICAL RELEVANCE The synECM seeded with synMSCs or synMSCs cotransduced with GFP, or BMP-2 yielded a bioactive synovial scaffold. Expression of BMP-2 by synMSCs cotransduced to enhance expression of BMP-2 or GFP and an accompanying increase in both HA and PG expression indicated production of anabolic agents and synoviocyte differentiation in the scaffold. Because BMP-2 can promote repair of damaged cartilage, such a bioactive scaffold could be useful for treatment of injured cartilage.

The objective of this study was to evaluate the impact of a trap-neuter-return (TNR) event on the size of free-roaming rural cat colonies in Quebec. This prospective randomized, controlled study included 18 cat colonies around barns and stables that were randomly assigned to either a TNR group (10 colonies of 7 to 27 cats; 14.3 cats on average) or a control group (8 colonies of 7 to 26 cats; 14.5 cats on average). The number of cats in each colony was calculated from the images obtained by camera-trapping at: baseline (T0), 7.5 mo (T7), and 12 mo (T12). At baseline, the TNR group was subjected to a TNR event. When taking into account adults only, a significant growth difference was observed in the number of cats between the TNR group and the control group at T7 (P = 0.03). When including kittens as well as adults, a trend towards a lower growth of the TNR group compared to the control group was noted at T7 (P = 0.06). There was no difference in the number of kittens between the 2 groups at T7 (P = 0.49) or at T12 (P = 0.36). There was a trend towards more emigration in the control group at T12 (P = 0.095). Isolated TNR events have a low and temporary impact on colony size in Quebec's rural cat colonies.

OBJECTIVE To evaluate gene transfer of recombinant adeno-associated viral (rAAV) vectors with AAV2 or AAV5 capsid and encoding hyaluronic acid (HA) synthase-2 (HAS2) into joints of healthy dogs. ANIMALS 22 purpose-bred Beagles. PROCEDURES Plasmid expression cassettes encoding canine HAS2 (cHAS2) were assessed in vitro for concentration and molecular size of secreted HA. Thereafter, rAAV2-cHAS2 vectors at 3 concentrations and rAAV5-cHAS2 vectors at 1 concentration were each administered intra-articularly into the left stifle joint of 5 dogs; 2 dogs received PBS solution instead. Synovial fluid HA concentration and serum and synovial fluid titers of neutralizing antibodies against AAV capsids were measured at various points. Dogs were euthanized 28 days after treatment, and cartilage and synovium samples were collected for vector DNA and mRNA quantification and histologic examination. RESULTS Cell transfection with plasmids encoding cHAS2 resulted in an increase in production and secretion of HA in vitro. In vivo, the rAAV5-cHAS2 vector yielded uniform genome transfer and cHAS2 expression in collected synovium and cartilage samples. In contrast, rAAV2-cHAS2 vectors were detected inconsistently in synovium and cartilage samples and failed to produce clear dose-related responses. Histologic examination revealed minimal synovial inflammation in joints injected with rAAV vectors. Neutralizing antibodies against AAV capsids were detected in serum and synovial fluid samples from all vector-treated dogs. CONCLUSIONS AND CLINICAL RELEVANCE rAAV5-mediated transfer of the gene for cHAS2 into healthy joints of dogs by intra-articular injection appeared safe and resulted in vector-derived cHAS2 production by synoviocytes and chondrocytes. Whether this treatment may increase HA production by synoviocytes and chondrocytes in osteoarthritic joints remains to be determined.

Using lung tissues separated from 12-day-old chicken embryos, we attempted to obtain a novel population of stem cells, namely, chicken lung-derived mesenchymal stem cells (LMSCs), which exhibit spindle-like morphology. The results of colony-forming assay and population doubling assay demonstrated that LMSCs had enormous colony-forming, self-renewal, and proliferative potential. When appropriately induced, LMSCs could differentiate into osteoblasts, adypocytes, chondrocytes, and neurons; in other words, LMSCs had cross-embryonic layer differentiation potential under corresponding induction conditions. Aside from colony-forming, self-renewal, and multilineage differentiation capabilities, LMSCs were characterized by specific cell phenotypes. The results of immunohistochemistry and flow cytometry demonstrated that LMSCs consistently expressed OCT-4 - a specific gene marker expressed in pluripotent stem cells - and markers associated with MSCs such as CD29, CD73, CD90, and CD105. However, LMSCs lacked hematopoietic cell surface molecules such as CD34 and CD45. Primary LMSCs could be subcultured to passage 24 at most in vitro and karyotype analysis demonstrated that LMSCs possessed genomic stability. These unique characteristics were consistent with the characteristics of MSCs, which had been isolated from other tissues. This provides a foundation for LMSCs as a promising avenue for cellular transplantation therapy, regenerative medicine, and tissue engineering.

OBJECTIVE To compare the effects of MK-467 and hyoscine butylbromide on detomidine hydrochloride–induced cardiorespiratory and gastrointestinal changes in horses. ANIMALS 6 healthy adult horses. PROCEDURES Horses received detomidine hydrochloride (20 μg/kg, IV), followed 10 minutes later by MK-467 hydrochloride (150 μg/kg; DET-MK), hyoscine butylbromide (0.2 mg/kg; DET-HYO), or saline (0.9% NaCl) solution (DET-S), IV, in a Latin square design. Heart rate, respiratory rate, rectal temperature, arterial and venous blood pressures, and cardiac output were measured; blood gases and arterial plasma drug concentrations were analyzed; selected cardiopulmonary variables were calculated; and sedation and gastrointestinal borborygmi were scored at predetermined time points. Differences among treatments or within treatments over time were analyzed statistically. RESULTS With DET-MK, detomidine-induced hypertension and bradycardia were reversed shortly after MK-467 injection. Marked tachycardia and hypertension were observed with DET-HYO. Mean heart rate and mean arterial blood pressure differed significantly among all treatments from 15 to 35 and 15 to 40 minutes after detomidine injection, respectively. Cardiac output was greater with DET-MK and DET-HYO than with DET-S 15 minutes after detomidine injection, but left ventricular workload was significantly higher with DET-HYO. Borborygmus score, reduced with all treatments, was most rapidly restored with DET-MK. Sedation scores and pharmacokinetic parameters of detomidine did not differ between DET-S and DET-MK. CONCLUSIONS AND CLINICAL RELEVANCE MK-467 reversed or attenuated cardiovascular and gastrointestinal effects of detomidine without notable adverse effects or alterations in detomidine-induced sedation in horses. Further research is needed to determine whether these advantages are found in clinical patients and to assess whether the drug influences analgesic effects of detomidine.

OBJECTIVE To assess 2 human ELISA kits for measurement of angiopoietin-1 and -2 concentrations in canine plasma samples, determine whether plasma angiopoeitin-2 concentration differed between septic and healthy dogs, and determine the effect of tumor necrosis factor-α (TNF-α) stimulation on angiopoeitin-2 release from primary canine aortic endothelial cells (pCAECs) in vitro. ANIMALS 10 healthy dogs and 10 septic dogs. PROCEDURES Human angiopoietin-1 and -2 ELISAs were used to detect recombinant canine angiopoietins-1 and -2 in canine plasma samples. The angiopoietin-2 ELISA was further validated by use of plasma samples from healthy and septic dogs and supernatants of pCAEC cultures. Associations between plasma angiopoeitin-2 and C-reactive protein (CRP) concentrations were examined. RESULTS Angiopoeitin-2 but not angiopoeitin-1 was detected in canine plasma samples by the respective ELISAs. The angiopoeitin-2 ELISA had excellent dilutional linearity, parallelism, accuracy, precision, and reproducibility for measurements in canine plasma samples and pCAEC supernatants. Plasma angiopoeitin-2 concentration was significantly higher in septic dogs (median, 25.5 ng/mL) than in healthy dogs (median, 6.7 ng/mL) and was positively correlated with plasma CRP concentration (R2 = 0.60). Stimulation of pCAECs with TNF-α resulted in a significant increase in supernatant angiopoietin-2 concentration. CONCLUSIONS AND CLINICAL RELEVANCE The tested human angiopoietin-2 ELISA kit was useful for measuring angiopoietin-2 concentrations in canine plasma samples and pCAEC supernatants. Sepsis appeared to increase angiopoietin-2 concentration in dogs in vivo, whereas TNF-α stimulation caused release of angiopoietin-2 from pCAECs in vitro. These findings support the use of angiopoietin-2 as a marker of endothelial cell activation and inflammation in dogs.

OBJECTIVE To evaluate 3 contrast medium infusion (CMI) protocols for CT angiography (CTA) and measurement of major artery diameters in African grey parrots (Psittacus erithacus). ANIMALS 9 African grey parrots with no detectable cardiovascular disease. PROCEDURES Each bird was anesthetized and underwent placement of an IV catheter in the left basilic vein and 16-slice CTA scanning (started at peak aortic enhancement) with each of 3 CMI protocols at ≥ 1-month intervals. Protocol 1 involved catheter flushing with saline (0.9% NaCl) solution and IV infusion of iopamidol (2 mL) followed by saline solution (0.2 mL; total infused volume, 5 mL). Protocol 2 involved IV infusion of iopamidol (2 mL) followed by saline solution (0.4 mL; total infused volume, 2.4 mL). Protocol 3 involved catheter flushing with saline solution and IV administration of iopamidol (2 mL; total infused volume, 4.8 mL). The diameters of 6 major arteries were measured by 2 observers, and intra- and interobserver agreement, time-enhancement variables, and patient factors affecting contrast medium enhancement were assessed. RESULTS Among the 3 CMI protocols, CTA-derived arterial diameters differed significantly. Measurements obtained with protocol 2 were significantly larger than those obtained with the other protocols. Uniformity of the time-enhancement variables differed among CMI protocols. Patient factors had nonsignificant effects on contrast medium enhancement. CONCLUSIONS AND CLINICAL RELEVANCE Of the CMI protocols assessed, a 2-phase CMI protocol with a post-CMI saline solution flush was the most reliable for CTA-derived measurements of the major thoracic and abdominal arteries in African grey parrots. However, further technique modification is needed.