Influence of oblique proximal ulnar osteotomy on humeral intracondylar fissures in 35 spaniel breed dogs.

OBJECTIVE: To investigate the effects of oblique proximal ulnar osteotomy (PUO) on the healing of humeral intracondylar fissure (HIF) in spaniel breed dogs. STUDY DESIGN: Clinical retrospective study. SAMPLE POPULATION: A total of 51 elbows from 35 spaniel dogs. METHODS: An oblique PUO was performed in dogs diagnosed with HIF. The degree of healing of HIF was subjectively and objectively assessed on preoperative and long-term follow-up CT imaging. Objective assessment was performed by measuring the bone density in Hounsfield units (HU) of a rectangular region of interest (ROI) encompassing the entire hypoattenuated humeral fissure. Major and minor complications were recorded. RESULTS: A total of 24 partial and 27 complete HIFs were diagnosed. The follow-up CT scan was performed at a median 18.5 months (range 10-49 months). Subjective assessment confirmed partial or complete healing of the HIF in 41 elbows (80.3%). Objective assessment confirmed a difference in mean HU of the HIF's ROI between preoperative (HU 640) and last follow-up CT images (HU 835) (p = .001). Young dogs (<14 months) had the highest increase in HU of the HIF's ROI. Major complications occurred in five dogs (6 limbs) of which four were related to the lack of healing of the fissure (7.8%). CONCLUSION: Oblique PUO resulted in partial or complete healing of HIF and pain resolution in the majority of dogs. CLINICAL SIGNIFICANCE: This study introduces an innovative approach to achieve healing of the HIF in the dog, which may help reduce the high complication rate traditionally associated with the use of transcondylar screws.

Lower body weight and increasing age are significant risk factors for complications following bi-oblique proximal ulnar osteotomy in dogs.

OBJECTIVE: To report and evaluate the risk factors for complications following bi-oblique proximal ulnar osteotomy (PUO) in dogs. ANIMALS: 82 client-owned dogs (93 limbs). METHODS: Clinical records of dogs treated with bi-oblique PUO over a 5-year period were reviewed. Postoperative radiographs were analyzed, and osteotomy location and angles were recorded; follow-up radiographs were reviewed to assess the degree of osteotomy healing. Complications were classified as minor, major, and catastrophic. Logistic regression analysis was performed to investigate possible associations between the predictor variables and occurrence of complications. RESULTS: 82 dogs (93 limbs) were included. Postoperative complications were documented in 39 limbs (13 major and 26 minor). The most common major complication was osteotomy nonunion (8 limbs), while the most common minor complication was delayed union (21 limbs). Statistical analysis revealed that lower body weight (P = .01) and older age (P = .04) were significantly associated with the development of postoperative complications. CLINICAL RELEVANCE: In this study, lighter and older dogs were more likely to develop complications following bi-oblique proximal ulnar osteotomy. We did not identify an association between osteotomy angle and location on complication rate. Careful patient selection is therefore required to reduce the incidence of postoperative complications after bi-oblique PUO.

Functional outcomes of dogs undergoing shoulder arthrodesis with 2 locking compression plates.

OBJECTIVE: To report the outcomes of dogs undergoing shoulder arthrodesis with the application of 2 locking compression plates (LCPs). STUDY DESIGN: Retrospective case series. ANIMALS: Twelve client owned dogs undergoing shoulder arthrodesis using 2 LCPs as the principal method of fixation. METHODS: Medical records were searched for dogs who had undergone shoulder arthrodesis at a hospital between 2014-2021. Inclusion criteria required at least 6 months postoperative follow up and the use of 2 LCPs as the principal method of arthrodesis. Outcomes recorded include clinical assessment, Liverpool Osteoarthritis in Dogs (LOAD) scoring, force plate analysis, and a client visual-analogue scale with at least 6 months follow up. RESULTS: All shoulders were immobilized with 2 LCPs and no postoperative external coaptation. The duration of follow up was 855.9 days (174-2135). Minor complications were recorded in 2/12 dogs, neither requiring surgical revision. Preoperative to postoperative mean lameness scores reduced from 2.9 to 0.8 (0-5), with 11/12 dogs making a full functional recovery, with a mean long-term LOAD score of 12.9 (4-23). Gait analysis was available in 5/12 dogs, placing a mean of 31.9% of their bodyweight on the operated limb, with a mean symmetry index of 8.7%. Owners scores (n = 11/12) were consistent with a high level of satisfaction (9.6/10). CONCLUSION: Shoulder arthrodesis with 2 LCPs was associated with low morbidity and good outcomes in our clinical setting. CLINICAL SIGNIFICANCE: Canine shoulder arthrodesis performed with 2 LCPs should be considered as a suitable alternative in dogs with severe shoulder joint pathology.

The Effect of Femur Positioning on Measurement of Tibial Plateau Angle: An In Vitro Study.

Five canine cadaveric pelvic limbs with intact cranial cruciate ligaments were used to quantify the effect of variation in limb positioning on the radiographic measurement of the tibial plateau angle (TPA) with reference to the degree of femoral condyle superimposition. Intra-osseous pin placement and a custom jig design allowed the controlled three-dimensional manipulation of limbs. Medio-lateral digital radiographic projections were taken with perfect femoral hemicondylar superimposition to establish a "reference" TPA (difference in position = 0 mm), and subsequently in varying degrees of supination/pronation and abduction/adduction. The lack of femoral hemicondylar superimposition for each radiograph was quantified using a tangential line technique with reference to the long tibial axis. A total of 176 radiographs were each assessed by three observers. "True" TPA was measured and it ranged within 17-25° across all limbs assessed. Variation in femoral condylar positioning ranged from -13 mm to +13 mm proximo-distally, and -11 mm to +11 mm cranio-caudally. Moreover, 3 mm non-superimposition of the femoral condyles produced 90.6% of measurements with 1° difference between measured and "true" TPA, and a sensitivity of 97.9% for a 2° difference. Further reduction in femoral condylar superimposition to 4 mm reduced the frequency of 1° difference between measured and "true" TPA to 84.9%, and to 94.8% for a 2° difference. In conclusion, measurement of TPA in large breed dogs from radiographs with greater than 3 mm variation in femoral condylar superimposition should be interpreted with caution.

Complications after proximal abducting ulnar osteotomy and prognostic factors in 66 dogs.

OBJECTIVE: To report complications and prognostic factors in dogs undergoing proximal abducting ulnar osteotomy (PAUL). To evaluate the ability to predict complications on the basis of post-operative radiographic examination. STUDY DESIGN: Retrospective cohort study. ANIMALS: Sixty-six dogs. METHODS: Medical records of dogs treated with PAUL between 2014 and 2019 were reviewed for demographics, intraoperative findings, and post-operative complications. Post-operative radiographs were reviewed by two masked expert orthopedic surgeons, who were asked to predict the likelihood of major mechanical complications. The prognostic value of variables was tested with univariate and multivariable logistic regression. Inter-investigator agreement to predict complications was evaluated with two-by-two tables and kappa coefficient. RESULTS: Seventy-four PAULs in 66 dogs were included. Duration of follow-up ranged from 12 to 75 months (median: 53 months). Post-operative complications were documented in 19/74 limbs (16 dogs), including major complications in 13 limbs. These complications consisted mainly of non-union (six limbs), implant failure (two limbs), and infection (two limbs) requiring revision surgery in nine limbs. Body weight was the only variable associated with an increased risk of post-operative complications (p = .04). Agreement between expert predictions was low (respectively k = -0.08 and k = 0.11). CONCLUSION: Major complications were reported in one fourth of limbs treated with PAUL and were more likely as body weight increased. Suboptimal plate and screw placement or osteotomy reduction on post-operative radiographs were poorly predictive of complications. CLINICAL SIGNIFICANCE: Complications are fairly common after PAUL, particularly in heavier dogs, and post-operative radiographic examination seems unreliable to predict those.

Optimization of the ultrasoud-assisted extraction of saponins from quinoa (Chenopodium quinoa Wild) using response surface methodology.

BACKGROUND: Quinoa grain has a bitter tasting layer in the pericarp called saponin, a triterpenoid glycoside with industrial potential. Traditionally, quinoa saponins are extracted with a large amount of water, which is why ultrasound technology constitutes an emerging technological alternative which is considered efficient and profitable compared to traditional extraction methods. The objective of this research was to determine the amplitude, time, and concentration of ethanol that guarantee a higher content of saponin through extraction assisted by ultrasound. METHODS: To find the optimal extraction conditions, the response surface methodology was used using the Box Behnken design with 5 central points, taking as a response the content of saponins (expressed in oleanolic acid as it is the most abundant sapogenin). RESULTS: According to the results obtained, the R2 values were in agreement with the adjusted R2, showing that the data fit the model well. The results showed that ethanol concentration has a significant effect (p < 0.05) on the saponin content in the extract. Optimization showed that the optimal extraction conditions were 70% ethanol, 59% amplitude and an exposure time of 12 min. These values were obtained experimentally to compare theoretical values and found residual error percentages less than 3%. The emulsifying activity was evaluated, reporting a value of 52,495 units of emulsion activity per milliliter (UAE/mL), and the foaming stability indicated that 87.54% of the initial foam was maintained after 5 min, indicating high stability. CONCLUSIONS: The parameters of ethanol concentration, amplitude and time were optimized in the extraction of saponins, assisted by ultrasound. Furthermore, the extract obtained had good foaming and emulsifying characteristics, suggesting its suitability for use in industry.

Kinetic characterization of substrate-analogous inhibitors of tyrosinase.

The development of effective tyrosinase inhibitors has become increasingly important in the cosmetic, medicinal, and agricultural industries for application as antibrowning and depigmenting agents. The kinetic mechanisms of action of tyrosinase on monophenols and o-diphenols are complex, particularly in the case of monophenols because of the lag period that occurs at the beginning of the reaction. When enzyme inhibitors are studied, the problem becomes more complicated because the lag period increases, which has led to erroneous identification of the type of inhibition that many compounds exert on the monophenolase activity and the inaccurate determination of their inhibition constants. When the degrees of inhibition of an inhibitor which is analogous to tyrosinase substrates are the same for both monophenolase and diphenolase activities, this means that the inhibitor binds to the same enzymatic species and so the inhibition constants should be similar for both activities. In this study, we demonstrate this typical behavior of substrate-analogous inhibitors and propose a methodology for determining the type of inhibition and the inhibition constants for the monophenolase and diphenolase activities of the enzyme. Benzoic acid and cinnamic acid were used as inhibitors and the monophenol/o-diphenol pairs l-tyrosine/l-dopa and α-methyl-L-tyrosine/α-methyl-L-dopa as substrates.

Identificación de células proliferativas en quistes de Taenia solium / Identification of proliferating cells in Taenia solium cysts

Los neoblastos son células totipotentes, únicas responsables de la proliferación y maduración de tejidos en platelmintos de vida libre. Células similares se han aislado en platelmintos parásitos como Echinococcus. Taenia solium causa la teniasis humana (intestinal) y la cisticercosis en humanos y cerdos. La infección del cerebro con larvas (quistes) de T. solium resulta en neurocisticercosis, hiperendémica en el Perú; su tratamiento se asocia a síntomas neurológicos graves. La capacidad proliferativa y el desarrollo de los estadios de T. solium aún no se describen, y no se ha caracterizado los neoblastos de este parásito. Se buscó células proliferativas en quistes de T. solium colectados de un cerdo infectado, que fueron identificadas al replicarse e incorporar el nucleótido bromodesoxiuridina, detectado con un anticuerpo monoclonal. Una línea celular estable de neoblastos sería útil para estudios sistemáticos in vitro sobre eficacia de drogas y sobre la biología de T. solium.

Neoblasts are totipotent cells, solely responsible for the proliferation and maturation of tissues in free-living flatworms. Similar cells have been isolated from parasitic flatworms such as Echinococcus. Taenia solium causes human taeniasis (intestinal) and cysticercosis in humans and pigs. Brain infection with larvae (cysts) of T. solium results in neurocysticercosis which is hyperendemic in Peru, and its treatment is associated with serious neurological symptoms. The proliferative capacity and development stages of T. solium have not been described and the neoblasts of this parasite have not been characterized We looked for cell proliferation in T. solium cysts collected from an infected pig, which were identified when replicating and incorporating bromodeoxyuridine nucleotide detected with a monoclonal antibody. A stable cell line of neoblasts would be useful for systematic in vitro studies on drug efficacy and the biology of T. solium.

[Identification of proliferating cells in Taenia solium cysts]. / Identificación de células proliferativas en quistes de Taenia solium.

Neoblasts are totipotent cells, solely responsible for the proliferation and maturation of tissues in free-living flatworms. Similar cells have been isolated from parasitic flatworms such as Echinococcus. Taenia solium causes human taeniasis (intestinal) and cysticercosis in humans and pigs. Brain infection with larvae (cysts) of T. solium results in neurocysticercosis which is hyperendemic in Peru, and its treatment is associated with serious neurological symptoms. The proliferative capacity and development stages of T. solium have not been described and the neoblasts of this parasite have not been characterized We looked for cell proliferation in T. solium cysts collected from an infected pig, which were identified when replicating and incorporating bromodeoxyuridine nucleotide detected with a monoclonal antibody. A stable cell line of neoblasts would be useful for systematic in vitro studies on drug efficacy and the biology of T. solium.

Bi-oblique dynamic proximal ulnar osteotomy in dogs: reconstructed computed tomographic assessment of radioulnar congruence over 12 weeks.

OBJECTIVE: To evaluate radioulnar joint modification using computed tomography (CT) after bi-oblique dynamic proximal ulnar osteotomy (BODPUO). STUDY DESIGN: Clinical study. ANIMALS: Dogs (n = 18, 26 elbows) with elbow incongruence treated by a single surgeon with BODPUO. METHODS: Radioulnar space measurements were performed on transverse, frontal, and sagittal CT projections preoperatively and after radiographically determined osteotomy healing. RESULTS: Three transverse plane measurements were statistically different than preoperatively at 12 weeks after the surgery demonstrating divergence of the lateral coronoid region of the radial incisure of the ulna from the radial head. None of the other measurements within the elbow were statistically different, but measurements of the radioulnar space at the level of the osteotomy site documented a statistically significant caudal tipping of the distal extent of the proximal ulnar segment. CONCLUSION: CT measurements documented a significant increase in radioulnar joint space at the mid-coronoid level, at the level of the base of the medial coronoid process, and at the level of the lateral coronoid process. This corresponds to cranially directed rotation of the medial coronoid process around the proximal radial epiphysis. A tendency for cranial tilting of the medial coronoid process was observed, which was confirmed by statistically significant caudal tipping of the distal extent of the proximal ulnar segment.

Predictive variables for complications after TPLO with stifle inspection by arthrotomy in 1000 consecutive dogs.

OBJECTIVE: To evaluate risk factors for complications, including meniscal injury and infection, after tibial plateau leveling osteotomy (TPLO) in dogs. STUDY DESIGN: Retrospective case series. SAMPLE POPULATION: Dogs (n=1000; 1146 stifles) with cranial cruciate ligament (CCL) rupture that had TPLO. METHODS: Medical records (January 2004-March 2009) were reviewed for dogs operated sequentially by medial arthrotomy with instrumented meniscal inspection (IMI) and TPLO by a single experienced surgeon. Multiple logistic regression models were used to evaluate independent contribution of risk factors to the recorded complications. RESULTS: Overall complication rate was 14.8%, of which 6.6% were major complications. Incidence of primary meniscal injury (PMI) was 33.2%, and subsequent meniscal injury (SMI) 2.8%. Postoperative infection occurred in 6.6% dogs. Bilateral CCL rupture was diagnosed in 14.6% dogs and no statistically significant complication incidence difference was recorded for simultaneous or staged bilateral surgical procedures. Administration of postoperative antibacterial therapy and being a Labrador reduced infection incidence, whereas increased body-weight and being an intact male increased infection risk. Increased body-weight and complete (versus partial) CCL rupture were significant predictors of overall complications. CONCLUSIONS: Incidence of SMI recorded in this study is similar to that reported previously involving arthroscopic meniscal inspection at time of TPLO. Infection was the single most important complication and antibiotic therapy was protective. Complication rate did not differ between bilateral simultaneous or staged procedures. CLINICAL RELEVANCE: Complication rate after TPLO with arthrotomy and IMI is lower than previously reported, bilateral simultaneous TPLO is reasonable, and incidence of major complications compares favorably with general orthopedic procedures.