Life threatening hemorrhage associated with a dentigerous cyst in a dog: Case report.

Dentigerous cysts are the most common type of odontogenic cysts and arise from an unerupted tooth. These cysts have stereotypical radiographic and clinical findings. They can be extremely invasive but rarely present as a life-threatening emergency. This case report describes the stabilization and treatment of a 6-year-old mixed breed dog with a dentigerous cyst with concurrent life-threatening hemorrhage. The dog presented with severe oral hemorrhage from the mandibular artery and required multiple blood transfusions. It was ultimately diagnosed with a dentigerous cyst. Complications from dental issues and potential life-threatening complications, such as this case, can be prevented by routine annual oral examination and full mouth dental radiographs if an unerupted tooth is suspected.

Gamma Power as an Index of Sustained Attention in Simulated Vigilance Tasks.

Performance on the psychomotor vigilance test (PVT; Dinges & Powell, 1985)-a common index of sustained attention-is affected by the opposing forces of fatigue and sustained effort, where reaction times and error rates typically increase across trials and are sometimes offset by additional efforts deployed toward the end of the task (i.e., an "end-spurt"; cf. Bergum & Klein, 1961). In ACT-R (Adaptive Control of Thought-Rational; Anderson et al., 2004), these influences on task performance have been modeled as latent variables that are inferred from performance (e.g., Jongman, 1998; Veksler & Gunzelmann, 2018) without connections to directly observable variables. We propose the use of frontal gamma (γ) spectral power as a direct measure of vigilant effort and demonstrate its efficacy in modeling performance on the PVT in both the aggregate and in individuals.

Premature death in dogs with nontraumatic hemoabdomen and splenectomy with benign histopathologic findings.

OBJECTIVE: To determine whether premature death occurred among dogs with nonmalignant splenic histopathologic findings after splenectomy for nontraumatic hemoabdomen. ANIMALS: 197 dogs with nontraumatic hemoabdomen that underwent splenectomy and histopathologic evaluation between 2005 and 2018. PROCEDURES: Information was obtained from electronic medical records, dog owners, and referring veterinarians to determine patient characteristics, histopathologic findings, survival information, and cause of death. Dogs were grouped based on histopathological diagnosis and outcome, and median survival times (MSTs) and risk factors for death were determined. RESULTS: Histopathologic findings indicated malignancy in 144 of the 197 (73.1%) dogs with nontraumatic hemoabdomen. Hemangiosarcoma was diagnosed in 126 dogs (87.5% of those with malignancies and 64.0% of all dogs). Nine of 53 (17%) dogs with nonmalignant histopathologic findings had an adverse outcome and premature death, with an MST of 49 days. Risk factors for this outcome included low plasma total solids concentration, an elevated hemangiosarcoma likelihood prediction score, and a medium or high hemangiosarcoma likelihood prediction score category. CONCLUSIONS AND CLINICAL RELEVANCE: This study showed that there is a group of dogs with nontraumatic hemoabdomen due to splenic disease that have nonmalignant histopathologic findings after splenectomy, but nonetheless suffer an adverse outcome and die prematurely of a suspected malignancy. Further evaluation of potential at-risk populations may yield detection of otherwise overlooked malignancies.

Effects of morphine on histamine release from two cell lines of canine mast cell tumor and on plasma histamine concentrations in dogs with cutaneous mast cell tumor.

OBJECTIVE: To determine the effects of morphine on histamine release from 2 canine mast cell tumor (MCT) cell lines and on plasma histamine concentrations in dogs with cutaneous MCTs. ANIMALS: 10 dogs with cutaneous MCT and 10 dogs with soft tissue sarcoma (STS). PROCEDURES: The study consisted of 2 phases. First, 2 canine MCT cell lines were exposed to 3 pharmacologically relevant morphine concentrations, and histamine concentrations were determined by an ELISA. Second, dogs with MCT or STS received 0.5 mg of morphine/kg, IM, before surgery for tumor excision. Clinical signs, respiratory rate, heart rate, arterial blood pressure, rectal temperature, and plasma histamine concentrations were recorded before and 5, 15, 30, and 60 minutes after morphine administration but prior to surgery. Data were compared by use of a 2-way ANOVA with the Sidak multiple comparisons test. RESULTS: In the first phase, canine MCT cell lines did not release histamine when exposed to pharmacologically relevant morphine concentrations. In the second phase, no differences were noted for heart rate, arterial blood pressure, and rectal temperature between MCT and STS groups. Plasma histamine concentrations did not significantly differ over time within groups and between groups. CONCLUSIONS AND CLINICAL RELEVANCE: No significant changes in histamine concentrations were noted for both in vitro and in vivo study phases, and no hemodynamic changes were noted for the in vivo study phase. These preliminary results suggested that morphine may be used safely in some dogs with MCT.

Are age differences in recognition-based retrieval monitoring an epiphenomenon of age differences in memory?

Older adults often demonstrate a monitoring deficit by producing more high-confidence memory errors on recognition memory tests. To eliminate lower memory performance by older adults (OA) as a candidate explanation, we studied how distinctive encoding enhances the retrieval-monitoring accuracy in older adults and younger adults (YA) under different delays (2-day delay for OA, 7-day delay for YA). Individuals viewed items consisting of four randomly selected exemplars (e.g., SALMON, BASS, PERCH, and SHARK) from a taxonomic category (e.g., FISH), one being designated as the to-be-remembered target. Participants were randomly assigned to two encoding conditions: Shared (generate a shared feature of all exemplars, e.g., GILLS) or Distinctive (generate a distinctive feature of the designated target). We collected retrospective confidence judgments (RCJs) after a five-alternative forced-choice (5AFC) recognition test, with the lures being either previously presented (old) exemplars or new category exemplars. Recall and recognition memory were better with distinctive encoding, with shared feature generation producing more high-confidence false alarms (HCFAs). Distinctive encoding dramatically reduced HCFAs and improved RCJ resolution. Comparison of OA with 2-day delay YA revealed age differences in HCFA consistent with previous studies. As important, age differences in memory for OA and 7-day delay YA were minimized, eliminating age deficits in HCFAs. Matching OAs to a subset of 7-day delay YAs on recognition memory produced additional evidence favoring the null hypothesis of age-equivalence in HCFAs. The results therefore indicated that age differences in recognition-based retrieval monitoring in a forced-choice recognition test are an epiphenomenon of age differences in memory. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Why do learners ignore expected feedback in making metacognitive decisions about retrieval practice?

We report two experiments investigating why learners, in making metacognitive judgments, often seem to ignore or otherwise fail to appreciate that feedback following retrieval practice provides a restudy opportunity. Learners practiced word pairs for a final cued-recall test by studying each pair initially, making a judgment of learning (JOL), and then deciding whether to practice the pair again after a short or long spacing interval, or not at all. For different groups in Experiment 1, additional practice involved restudying, retrieval practice without feedback, or retrieval practice with feedback (the full pair). We used procedures (long feedback duration and covert retrieval practice) designed to rule out the possibility that feedback is ignored because it is usually brief or because participants' choices are influenced by a desire to look good by performing well on overt practice tests. In the relearning condition, learners preferred a long spacing interval for items at all JOL levels. Despite the feedback duration and the covert retrieval practice, learners in both retrieval-practice conditions preferred a short spacing interval for hard, low-JOL items and a long spacing interval for easy, high-JOL items, even though this may not be an effective strategy when feedback is provided. In Experiment 2, instructions framed feedback either as a presentation of the correct answer or as a restudy opportunity preceded by retrieval practice. Framing feedback as a restudy opportunity markedly changed the choices learners made. Apparently, the restudy function of feedback does not occur to learners unless they are specifically alerted to it.

Category norms with a cross-sectional sample of adults in the United States: Consideration of cohort, age, and historical effects on semantic categories.

This paper describes normative data for newly collected exemplar responses to 70 semantic categories described in previous norming studies (Battig & Montague, Journal of Experimental Psychology, 80(3, pt.2): 1-46, 1969; Van Overschelde, Rawson, & Dunlosky, Journal of Memory and Language, 50(3): 289-335, 2004; Yoon et al., Psychology and Aging, 19(3), 379-393, 2004). These categories were presented to 246 young (18-39 years), middle (40-59 years), and older (60 years and older) English-speaking adults living in the United States who were asked to generate as many category exemplars as possible for each of the 70 categories. In order to understand differences in normative responses, we analyzed these responses a) between age groups within the current sample and b) in comparison to three previously published sets of norms. Experimental studies using such norms typically assume invariance of normative likelihoods across age and historical time. We replicate previous findings such that exemplar frequency correlations suggest moderate stability in generated category members between age groups and cohorts for many, but not all, categories. Further, analyses of rank-order correlations highlight that the traditional measure of typicality may not capture all aspects of typicality, namely that for some categories there is high consistency in the frequency of exemplars across age groups and/or norms, but the ordering of those exemplars differs significantly. We include a cluster analysis to aid in grouping categories based on relative stability across time, cohort, and age groups. These results emphasize the importance of maintaining and updating age-differentiated category norms.

Evaluation of Fecal Sand Clearance in Horses With Naturally Acquired Colonic Sand Accumulation With a Product Containing Probiotics, Prebiotics, and Psyllium.

Consumption of sand and dirt in horses can cause chronic diarrhea and colic because of irritation and obstruction of the gastrointestinal tract of horses. Prevention has primarily focused on changes in management to reduce the intake of sand and feeding of psyllium products. The purpose of this study was to evaluate the efficacy of a product containing probiotics, prebiotics, and psyllium in the clearance of colonic sand in horses with naturally acquired sand accumulation using a randomized, placebo-controlled, blinded clinical trial format. After identification of 10 horses with sand accumulation as determined by both auscultation and abdominal radiography, quantitative assessment of changes in colonic sand content in response to management changes combined with treatment with the probiotic/psyllium product or no treatment was assessed by blinded observers. Fecal sand output was monitored in both groups via sand sedimentation analysis of fecal samples every 3 days for 35 days and with pre- and post-treatment abdominal radiography. There was a significant reduction in sand accumulation in both treatment and control groups, but there were no significant differences between treatment and control groups in clearance of colonic sand as measured by both fecal sand sedimentation and quantitative radiography.

Modeling Framework Used to Analyze and Describe Junctional Tourniquet Skills.

Medical educators have acknowledged the importance of simulation training in developing procedural skills. While simulation training in other disciplines has benefitted from evaluations of users' skill acquisition, the majority of medical training simulators continue to be developed from overly simplified descriptions of procedures, such as techniques prescribed by existing instructional material. Our objective was to use a modeling framework to characterize the skill of various users in applying junctional tourniquets in order to design an effective training simulator. We recorded 46 medical first responders performing training exercises applying a junctional tourniquet and used coded video and sensor data to identify the hierarchy of actions they performed in the process. The model provides several insights into trainee performance, such as the way in which advanced users perform more tasks in parallel, or areas where advanced users employ situational awareness to identify ways they can deviate from recommended protocol to improve outcomes. The model successfully identifies variations in tourniquet application technique that correlates with improvement on clinically relevant metrics including application speed, pressure applied, and tourniquet placement stability. This methodology can improve medical training simulations by indicating changes during the course of learning a new task, such as helpful deviations from instructional protocol.