Keratinocytes drive the epithelial hyperplasia key to sea lice resistance in coho salmon.

BACKGROUND: Salmonid species have followed markedly divergent evolutionary trajectories in their interactions with sea lice. While sea lice parasitism poses significant economic, environmental, and animal welfare challenges for Atlantic salmon (Salmo salar) aquaculture, coho salmon (Oncorhynchus kisutch) exhibit near-complete resistance to sea lice, achieved through a potent epithelial hyperplasia response leading to rapid louse detachment. The molecular mechanisms underlying these divergent responses to sea lice are unknown. RESULTS: We characterized the cellular and molecular responses of Atlantic salmon and coho salmon to sea lice using single-nuclei RNA sequencing. Juvenile fish were exposed to copepodid sea lice (Lepeophtheirus salmonis), and lice-attached pelvic fin and skin samples were collected 12 h, 24 h, 36 h, 48 h, and 60 h after exposure, along with control samples. Comparative analysis of control and treatment samples revealed an immune and wound-healing response that was common to both species, but attenuated in Atlantic salmon, potentially reflecting greater sea louse immunomodulation. Our results revealed unique but complementary roles of three layers of keratinocytes in the epithelial hyperplasia response leading to rapid sea lice rejection in coho salmon. Our results suggest that basal keratinocytes direct the expansion and mobility of intermediate and, especially, superficial keratinocytes, which eventually encapsulate the parasite. CONCLUSIONS: Our results highlight the key role of keratinocytes in coho salmon's sea lice resistance and the diverged biological response of the two salmonid host species when interacting with this parasite. This study has identified key pathways and candidate genes that could be manipulated using various biotechnological solutions to improve Atlantic salmon sea lice resistance.

The Importance of Adhering to Terminology When Implementing Competency-Based Veterinary Education (CBVE).

The American Association of Veterinary Medical Colleges (AAVMC) Competency-Based Veterinary Education (CBVE) Model was developed with consideration of the lessons learned over the past 20 years by other health care professions regarding the implementation of outcomes-based education. As veterinary education programs consider the benefits of outcomes-based training, and more programs begin adopting this model of education, it is more critical than ever to ensure fidelity of the model for successful implementation. Fidelity, or the accuracy with which something is reproduced, was identified as an important factor in successfully implementing competency-based training in medical education (CBME). Without fidelity of the core components of CBME as defined in the medical education literature, programs were challenged to evaluate the effectiveness of the new educational model, and in some cases, this led to premature notions of failure when all components of CBME had not been successfully implemented. Consistency in terminology related to competency-based education is critical for successful implementation of the CBVE Model. The terminology used in higher education, and in other disciplines, describes concepts that are underpinned by research, just as they are in competency-based education. Without shared understanding and accurate use of terminology to describe the tools and strategies used in CBVE, there is a considerable risk of failure or even perceived failure in transitioning to CBVE. The authors of this commentary, the AAVMC Council on Outcomes-based Veterinary Education, continue to encourage veterinary programs across the world to recognize the value of the AAVMC CBVE Model in transforming veterinary education. Through use of shared terminology and consistent application of the components of the model, we envision the expansion of CBVE as an opportunity to advance veterinary education and to promote new graduate success in the veterinary profession.

Implementing Competency-Based Veterinary Education: A Survey of AAVMC Member Institutions on Opportunities, Challenges, and Strategies for Success.

Competency-based education is increasingly being adopted across the health professions. A model for competency-based education in veterinary medicine was recently developed by a working group of the American Association of Veterinary Medical Colleges (AAVMC) and is being used in institutions worldwide. The purpose of this study was to gather information on progress in and barriers to implementing competency-based education (including use of the AAVMC competency-based veterinary education [CBVE] Model) by AAVMC member schools to inform the development of strategies to support institutions in successful implementation of the CBVE Model. A cross-sectional survey was developed and distributed to AAVMC member institutions via an AAVMC web-based communication platform. Thirty-four of 55 AAVMC member institutions responded to the survey (62% response rate). Twenty schools reported using a competency-based education framework. Eleven of these institutions had implemented the AAVMC CBVE Framework, with an additional 12 institutions anticipating implementing it over the next 3 years. Timing, resources, and change management were the most commonly reported challenges to implementation. Suggestions for development of training resources included translation of milestones to pre-clinical courses, development of assessments, guidance on making progress decisions, illustrative overviews of specific components of the CBVE Model (e.g., the AAVMC CBVE Framework, EPAs, entrustment scales, milestones), and curriculum mapping. This study assesses progress in implementing the CBVE Model in AAVMC member schools and aids in identifying key challenges and resources to support faculty and institutions in the successful adoption and implementation of this educational model.

Obturator-Assisted Prolapse for Access to and Sampling of Colorectal Masses in Seven Dogs.

The gold standard for diagnosis of colorectal masses is surgical biopsy; however, this is not always logistically or economically feasible. The authors present an alternative to established flexible and rigid endoscopic approaches when case limitations require such an approach. In seven dogs, after the identification of a mass on physical exam and computed tomographic evaluation, the colorectum was accessed using obturator-assisted prolapse to isolate discrete masses and perform shielded sampling via core needle biopsy. Histopathologic diagnosis was adequate for treatment planning in all dogs. No major complications were recorded 65-475 days after the procedure. This technique may be useful when traditional endoscopy and surgery for biopsy of colorectal masses is unavailable.

Collaborative Development of Core Entrustable Professional Activities for Veterinary Education.

Entrustable professional activities (EPAs) have been proposed as a practical framework for the implementation of competency-based education. As veterinary education moves toward a competency-based approach, core EPAs provide a context for assessment of workplace activities. This article reports on the development of eight core clinical EPAs for veterinary education created through multi-institutional collaboration, with international input from veterinary educators and veterinary educational leaders. These core EPAs are intended as minimal expectations for clinical activities that should be assessed for every graduate of Association of American Veterinary Medical Colleges member institutions. Adoption of the core EPAs and the associated Competency-Based Veterinary Education (CBVE) framework by veterinary schools is intended to promote Day One graduate competence and thereby enhance patient care and client service.

Collaborative Development of a Shared Framework for Competency-Based Veterinary Education.

Competency-based medical education is an educational innovation implemented in health professions worldwide as a means to ensure graduates meet patient and societal needs. The focus on student-centered education and programmatic outcomes offers a series of benefits to learners, institutions and society. However, efforts to establish a shared, comprehensive competency-based framework in veterinary education have lagged. This article reports on the development and outcome of a competency-based veterinary education (CBVE) framework created through multi-institutional collaboration with international input from veterinary educators and veterinary educational leaders. The CBVE Framework is designed to reflect the competencies expected of new graduates from member institutions of the Association of American Veterinary Medical Colleges (AAVMC). The CBVE Framework consists of nine domains of competence and 32 competencies, each supplemented with illustrative sub-competencies to guide veterinary schools in implementing competency-based education in their local context. The nine domains of competence are: clinical reasoning and decision-making; individual animal care and management; animal population care and management; public health; communication; collaboration; professionalism and professional identity; financial and practice management; and scholarship. Developed through diverse input to facilitate broad adoption, the CBVE Framework provides the foundation for competency-based curricula and outcomes assessment in veterinary education internationally. We believe that other groups seeking to design a collective product for broad adoption might find useful the methods used to develop the CBVE Framework, including establishing expertise diversity within a small-to-medium size working group, soliciting progressive input and feedback from stakeholders, and engaging in consensus building and critical reflection throughout the development process.

Development of core entrustable professional activities linked to a competency-based veterinary education framework.

Purpose: Despite the adoption of competency-based education in some veterinary schools over the past 15 years, only recently has a concerted effort been directed toward this in veterinary education internationally.Methods: In 2015, educational leaders from the Association of American Veterinary Medical Colleges (AAVMC) member schools came together with a strong call to action to create shared tools for clinical competency assessment.Results: This resulted in the formation of the AAVMC Competency-Based Veterinary Education (CBVE) Working Group, which then embarked on the creation of a shared competency framework and the development of eight core entrustable professional activities (EPAs) linked to this framework.Conclusions: This paper will report on the development of these EPAs and their integration with the concurrently-developed CBVE Framework.

Transverse Compression of Tendons.

A study was made of the deformation of tendons when compressed transverse to the fiber-aligned axis. Bovine digital extensor tendons were compression tested between flat rigid plates. The methods included: in situ image-based measurement of tendon cross-sectional shapes, after preconditioning but immediately prior to testing; multiple constant-load creep/recovery tests applied to each tendon at increasing loads; and measurements of the resulting tendon displacements in both transverse directions. In these tests, friction resisted axial stretch of the tendon during compression, giving approximately plane-strain conditions. This, together with the assumption of a form of anisotropic hyperelastic constitutive model proposed previously for tendon, justified modeling the isochronal response of tendon as that of an isotropic, slightly compressible, neo-Hookean solid. Inverse analysis, using finite-element (FE) simulations of the experiments and 10 s isochronal creep displacement data, gave values for Young's modulus and Poisson's ratio of this solid of 0.31 MPa and 0.49, respectively, for an idealized tendon shape and averaged data for all the tendons and E = 0.14 and 0.10 MPa for two specific tendons using their actual measured geometry. The compression load versus displacement curves, as measured and as simulated, showed varying degrees of stiffening with increasing load. This can be attributed mostly to geometrical changes in tendon cross section under load, varying according to the initial 3D shape of the tendon.

Viscoelasticity of Tendons Under Transverse Compression.

Tendons are highly anisotropic and also viscoelastic. For understanding and modeling their 3D deformation, information is needed on their viscoelastic response under off-axis loading. A study was made, therefore, of creep and recovery of bovine digital extensor tendons when subjected to transverse compressive stress of up to ca. 100 kPa. Preconditioned tendons were compression tested between glass plates at increasing creep loads. The creep response was anomalous: the relative rate of creep reduced with the increasing stress. Over each ca. 100 s creep period, the transverse creep deformation of each tendon obeyed a power law dependence on time, with the power law exponent falling from ca. 0.18 to an asymptote of ca. 0.058 with the increasing stress. A possible explanation is stress-driven dehydration, as suggested previously for the similar anomalous behavior of ligaments. Recovery after removal of each creep load was also anomalous. Relative residual strain reduced with the increasing creep stress, but this is explicable in terms of the reducing relative rate of creep. When allowance was made for some adhesion occurring naturally between tendon and the glass plates, the results for a given load were consistent with creep and recovery being related through the Boltzmann superposition principle (BSP). The tendon tissue acted as a pressure-sensitive adhesive (PSA) in contact with the glass plates: explicable in terms of the low transverse shear modulus of the tendons.

Fibroblast growth factor signaling regulates the expansion of A6-expressing hepatocytes in association with AKT-dependent ß-catenin activation.

BACKGROUND & AIMS: Fibroblast Growth Factors (FGFs) promote the proliferation and survival of hepatic progenitor cells (HPCs) via AKT-dependent ß-catenin activation. Moreover, the emergence of hepatocytes expressing the HPC marker A6 during 3,5-diethoxycarbonyl-1,4-dihydrocollidine (DDC)-induced liver injury is mediated partly by FGF and ß-catenin signaling. Herein, we investigate the role of FGF signaling and AKT-mediated ß-catenin activation in acute DDC liver injury. METHODS: Transgenic mice were fed DDC chow for 14days concurrent with either Fgf10 over-expression or inhibition of FGF signaling via expression of soluble dominant-negative FGF Receptor (R)-2IIIb. RESULTS: After 14days of DDC treatment, there was an increase in periportal cells expressing FGFR1, FGFR2, and AKT-activated phospho-Serine 552 (pSer552) ß-Catenin in association with up-regulation of genes encoding the FGFR2IIIb ligands, Fgf7, Fgf10, and Fgf22. In response to Fgf10 over-expression, there was an increase in the number of pSer552-ß-Catenin((positive)+ive) periportal cells as well as cells co-positive for A6 and hepatocyte marker, Hepatocyte Nuclear Factor-4α (HNF4α). A similar expansion of A6(+ive) cells was observed after Fgf10 over-expression with regular chow and after partial hepatectomy during ethanol toxicity. Inhibition of FGF signaling increased the periportal A6(+ive)HNF4α(+ive) cell population while reducing centrolobular A6(+ive) HNF4α(+ive) cells. AKT inhibition with Wortmannin attenuated FGF10-mediated A6(+ive)HNF4α(+ive) cell expansion. In vitro analyses using FGF10 treated HepG2 cells demonstrated AKT-mediated ß-Catenin activation but not enhanced cell migration. CONCLUSIONS: During acute DDC treatment, FGF signaling promotes the expansion of A6-expressing liver cells partly via AKT-dependent activation of ß-Catenin expansion of A6(+ive) periportal cells and possibly by reprogramming of centrolobular hepatocytes.

Prepopulated radiology report templates: a prospective analysis of error rate and turnaround time.

Current speech recognition software allows exam-specific standard reports to be prepopulated into the dictation field based on the radiology information system procedure code. While it is thought that prepopulating reports can decrease the time required to dictate a study and the overall number of errors in the final report, this hypothesis has not been studied in a clinical setting. A prospective study was performed. During the first week, radiologists dictated all studies using prepopulated standard reports. During the second week, all studies were dictated after prepopulated reports had been disabled. Final radiology reports were evaluated for 11 different types of errors. Each error within a report was classified individually. The median time required to dictate an exam was compared between the 2 weeks. There were 12,387 reports dictated during the study, of which, 1,173 randomly distributed reports were analyzed for errors. There was no difference in the number of errors per report between the 2 weeks; however, radiologists overwhelmingly preferred using a standard report both weeks. Grammatical errors were by far the most common error type, followed by missense errors and errors of omission. There was no significant difference in the median dictation time when comparing studies performed each week. The use of prepopulated reports does not alone affect the error rate or dictation time of radiology reports. While it is a useful feature for radiologists, it must be coupled with other strategies in order to decrease errors.

Genetic Causes and Consequences of Sympatric Morph Divergence in Salmonidae: A Search for Mechanisms.

Repeatedly and recently evolved sympatric morphs exhibiting consistent phenotypic differences provide natural experimental replicates of speciation. Because such morphs are observed frequently in Salmonidae, this clade provides a rare opportunity to uncover the genomic mechanisms underpinning speciation. Such insight is also critical for conserving salmonid diversity, the loss of which could have significant ecological and economic consequences. Our review suggests that genetic differentiation among sympatric morphs is largely nonparallel apart from a few key genes that may be critical for consistently driving morph differentiation. We discuss alternative levels of parallelism likely underlying consistent morph differentiation and identify several factors that may temper this incipient speciation between sympatric morphs, including glacial history and contemporary selective pressures. Our synthesis demonstrates that salmonids are useful for studying speciation and poses additional research questions to be answered by future study of this family.

Venom kinematics during prey capture in Conus: the biomechanics of a rapid injection system.

Cone snails use an extensile, tubular proboscis as a conduit to deliver a potent cocktail of bioactive venom peptides into their prey. Previous studies have focused mainly on understanding the venom's role in prey capture but successful prey capture requires both rapid physiological and biomechanical mechanisms. Conus catus, a fish-hunting species, uses a high-speed hydraulic mechanism to inject its hollow, spear-like radular tooth into prey. We take an integrated approach to investigating the biomechanics of this process by coupling kinematic studies with morphological analyses. Taking advantage of the opaque venom and translucent proboscis of a mollusc-hunting juvenile cone snail, Conus pennaceus, we have determined that a high-speed prey capture mechanism is not unique to cone species that hunt fish prey. Two morphological structures were found to play crucial roles in this process. A constriction of the lumen near the tip of the proboscis, composed of tall epithelial cells densely packed with microfilaments, impedes forward movement of the radular tooth prior to its propulsion. Proximal to the constriction, a muscular sphincter was found to regulate venom flow and pressurization in the proboscis. In C. pennaceus, the rapid appearance and flushing of venom within the proboscis during prey capture suggests a mechanism involving the delivery of a discrete quantity of venom. The interplay between these elements provides a unique and effective biomechanical injection system for the fast-acting cone snail venom peptides.

Pancreatic abscess in 36 dogs: a retrospective analysis of prognostic indicators.

Thirty-six dogs were diagnosed with pancreatic abscess by the presence of purulent exudate within the parenchyma of the pancreas during exploratory laparotomy. Data regarding history, physical examination findings, clinicopathological data, diagnostic imaging findings, bacteriological culture results, abdominal drainage technique, and perioperative treatment were evaluated for factors predictive of survival. Elevated blood urea nitrogen, serum alkaline phosphatase activity, and rising bicarbonate ion concentration were each found to have statistically significant (P<0.05) influences on survival to discharge. Twenty-two (71%) of 36 dogs died or were euthanized prior to discharge from the hospital.

2007 Norden-Pfizer Distinguished Teacher. Evolution of a teacher: helping students learn.

I was honored to receive the 2007 National Carl J. Norden-Pfizer Distinguished Teacher Award. This award reflects the impact that my mentors and students have had on my teaching. I have been fortunate to have dedicated mentors and wonderful students. It is through the support and guidance of colleagues and students that I have been able to grow as a teacher. My students have taught me a lot about being an effective teacher. I will share some key principles that I try to follow in my teaching. These principles can be used in any teaching situation in any discipline.

Spontaneous retrograde movement of ureteroliths in two dogs and five cats.

CASE DESCRIPTION: 2 dogs and 5 cats were evaluated for treatment of ureteroliths. CLINICAL FINDINGS: Spontaneous retrograde movement of 1 or more ureteroliths was detected by radiography, ultrasonography, fluoroscopy, and a combination of fluoroscopy and ultrasonography. The ureteroliths moved retrograde up to 4 centimeters. Retrograde movement of ureteroliths into the renal pelvis resulted in improved renal function in some patients but made complete surgical removal of all uroliths more difficult. TREATMENT AND OUTCOME: Medical management was not successful, and ureteroliths were surgically removed. Surgical management of ureteroliths was complicated by retrograde movement of ureteroliths in the perioperative period. CLINICAL RELEVANCE: Ureteroliths can move retrograde within the ureter and even back into the renal pelvis. Retrograde movement of ureteroliths may make surgical planning more difficult.

Crystallization of a derivative of a new coenzyme, methoxatin.

A new compound, derived from a parent compound to which we have given the trivial name, methoxatin, has been isolated from a methanol-oxidizing bacterium, and crystallized. Its chemical structure was determined by X-ray crystallography. Methoxatin is implicated as a coenzyme in the oxidation of substrate alcohols. This report describes the purification and crystallization of the derivative, acetonyl methoxatin.