Masking by hypokalemia-primary aldosteronism with undetectable aldosterone.

Primary aldosteronism is the most common cause of secondary hypertension; however, the dynamic regulation of aldosterone by potassium is less well studied and current diagnostic recommendations are imprecise. We describe a young man who presented with resistant hypertension and severe hypokalemia. The workup initially revealed undetectable aldosterone despite acute potassium repletion. Chronic potassium supplementation eventually uncovered hyperaldosteronism. In situ genetic studies revealed a gain-of-function KCNJ5 mutation within an aldosterone-producing adenoma that was clinically responsive to changes in extracellular potassium. We highlight a unique presentation of Conn's syndrome and discuss the implications for the molecular mechanisms of potassium regulation of aldosterone.

Comparison of needle arthroscopy, traditional arthroscopy, and computed tomography for the evaluation of medial coronoid disease in the canine elbow.

OBJECTIVE: To evaluate the diagnostic value of still images of needle arthroscopy (SNAR), still images of traditional arthroscopy (STAR), and computed tomography (CT) to diagnose medial coronoid process (MCP) pathology. STUDY DESIGN: Prospective clinical trial. ANIMALS: Dogs (n = 17) presented for evaluation of elbow dysplasia. METHODS: For each case, two SNAR and STAR images of the MCP were reviewed independently and in random order by three board-certified surgeons. Computed tomographic images were reviewed by one board-certified radiologist. Reviewers were blinded to surgical and clinical findings. Surgical findings from real-time TAR with palpation were used as the gold standard. Receiver operating characteristic (ROC) curves and concordance statistics tests for the diagnostic accuracy of MCP fissure, MCP fragment, medial compartment condition, and cartilage score were calculated. RESULTS: Images of 27 elbows joints were reviewed. For MCP fissure detection, areas under the ROC curves for CT (0.84), STAR (0.73), and SNAR (0.57) did not differ. For the detection of MCP fragment, STAR had a larger area under the ROC curve (0.93) compared with SNAR (0.74, P = .015) and CT (0.54, P < .001). Still images of TAR and SNAR had comparable concordance for cartilage score (0.80 and 0.77, respectively) and medial compartment pathology (0.80 and 0.73, respectively). CONCLUSION: Still images of NAR, STAR, and CT had similar diagnostic value to identify MCP fissures. Still images of TAR was superior to SNAR and CT to identify MCP fragments. CLINICAL SIGNIFICANCE: The diagnostic accuracy of SNAR varied on the basis of the coronoid lesion being evaluated.

Comparison of torsional properties between a Fixateur Externe du Service de Santé des Armées and an acrylic tie-in external skeletal fixator in a red-tailed hawk (Buteo jamaicensis) synthetic tibiotarsal bone model.

OBJECTIVE: To compare the torsional mechanical properties of 2 external skeletal fixators (ESFs) placed with 2 intramedullary pin (IP) and transfixation pin (TP) size combinations in a model of raptor tibiotarsal bone fracture. SAMPLE: 24 ESF-synthetic tibiotarsal bone model (polyoxymethylene) constructs. PROCEDURES: Synthetic bone models were fabricated with an 8-mm (simulated fracture) gap. Four types of ESF-synthetic bone model constructs (6/group) were tested: a FESSA with a 1.6-mm IP and 1.6-mm TPs, a FESSA with a 2.0-mm IP and 1.1-mm TPs, an acrylic connecting bar with a 1.6-mm IP and 1.6-mm TPs, and an acrylic connecting bar with a 2.0-mm IP and 1.1-mm TPs. Models were rotated in torsion (5°/s) to failure or the machine angle limit (80°). Mechanical variables at yield and at failure were determined from load deformation curves. Effects of overall construct type, connecting bar type, and IP and TP size combination on mechanical properties were assessed with mixed-model ANOVAs. RESULTS: Both FESSA constructs had significantly greater median stiffness and median torque at yield than both acrylic bar constructs; FESSA constructs with a 1.6-mm IP and 1.6-mm TPs had greatest stiffness of all tested constructs and lowest gap strain at yield. No FESSA constructs failed during testing; 7 of 12 acrylic bar constructs failed by fracture of the connecting bar at the interface with a TP. CONCLUSIONS AND CLINICAL RELEVANCE: Although acrylic bar ESFs have been successfully used in avian patients, the FESSA constructs in this study were mechanically superior to acrylic bar constructs, with greatest benefit resulting from use with the larger TP configuration.

Radiation exposure of dogs and cats undergoing fluoroscopic procedures and for operators performing those procedures.

OBJECTIVE: To evaluate radiation exposure of dogs and cats undergoing procedures requiring intraoperative fluoroscopy and for operators performing those procedures. SAMPLE: 360 fluoroscopic procedures performed at 2 academic institutions between 2012 and 2015. PROCEDURES: Fluoroscopic procedures were classified as vascular, urinary, respiratory, cardiac, gastrointestinal, and orthopedic. Fluoroscopy operators were classified as interventional radiology-trained clinicians, orthopedic surgeons, soft tissue surgeons, internists, and cardiologists. Total radiation exposure in milligrays and total fluoroscopy time in minutes were obtained from dose reports for 4 C-arm units. Kruskal-Wallis equality of populations rank tests and Dunn pairwise comparisons were used to compare differences in time and exposure among procedures and operators. RESULTS: Fluoroscopy time (median, 35.80 minutes; range, 0.60 to 84.70 minutes) was significantly greater and radiation exposure (median, 137.00 mGy; range, 3.00 to 617.51 mGy) was significantly higher for vascular procedures than for other procedures. Median total radiation exposure was significantly higher for procedures performed by interventional radiology-trained clinicians (16.10 mGy; range, 0.44 to 617.50 mGy), cardiologists (25.82 mGy; range, 0.33 to 287.45 mGy), and internists (25.24 mGy; range, 3.58 to 185.79 mGy). CONCLUSIONS AND CLINICAL RELEVANCE: Vascular fluoroscopic procedures were associated with significantly longer fluoroscopy time and higher radiation exposure than were other evaluated fluoroscopic procedures. Future studies should focus on quantitative radiation monitoring for patients and operators, importance of operator training, intraoperative safety measures, and protocols for postoperative monitoring of patients.

Factor structure of the Personal Growth Initiative Scale-II: Evidence of a bifactor model.

Personal growth initiative has been shown to be an important predictor of psychological health. It is currently measured by the Personal Growth Initiative Scale-II (PGIS-II), which consists of 4 interrelated factors. Past research across various samples has consistently selected the 4-factor model as the best fit for the data compared to single-factor and second-order models. However, its fit has typically been adequate (not strong), and, to date, no research has examined alternate factor structures, such as a bifactor solution. The current study examined 4 theoretically informed potential models-single-factor, 4-factor, second-order 4 factor, and bifactor-across 3 samples drawn from different populations: 223 college students, 307 Mechanical Turk participants, and 281 clinical therapy clients. Across all 3 samples, the bifactor model was the best fit for the data, and tests of multigroup invariance indicated this model was invariant through the scalar level. Finally, analyses of the explained common variance and percentage of uncontaminated correlations indicated that the PGIS-II can be appropriately modeled unidimensionally. (PsycINFO Database Record