A randomized controlled pilot trial comparing the impact of access to clinical endocrinology video demonstrations with access to usual revision resources on medical student performance of clinical endocrinology skills.

BACKGROUND: Demonstrating competence in clinical skills is key to course completion for medical students. Methods of providing clinical instruction that foster immediate learning and potentially serve as longer-term repositories for on-demand revision, such as online videos demonstrating competent performance of clinical skills, are increasingly being used. However, their impact on learning has been little studied. The aim of this study was to determine the value of adjunctive on-demand video-based training for clinical skills acquisition by medical students in endocrinology. METHODS: Following an endocrinology clinical tutorial program, 2nd year medical students in the pre-assessment revision period were recruited and randomized to either a set of bespoke on-line clinical skills training videos (TV), or to revision as usual (RAU). The skills demonstrated on video were history taking in diabetes mellitus (DMH), examination for diabetes lower limb complications (LLE), and examination for signs of thyroid disease (TE). Students were assessed on these clinical skills in an observed structured clinical examination two weeks after randomization. Assessors were blinded to student randomization status. RESULTS: For both diabetes related clinical skills assessment tasks, students in the TV group performed significantly better than those in the RAU group. There were no between group differences in thyroid examination performance. For the LLE, 91.7% (n = 11/12) of students randomized to the video were rated globally as competent at the skill compared with 40% (n = 4/10) of students not randomized to the video (p = 0.024). For the DMH, 83.3% (n = 10/12) of students randomized to the video were rated globally as competent at the skill compared with 20% (n = 2/10) of students not randomized to the video (p = 0.007). CONCLUSION: Exposure to high quality videos demonstrating clinical skills can significantly improve medical student skill performance in an observed structured clinical examination of these skills, when used as an adjunct to clinical skills face-to-face tutorials and deliberate practice of skills in a blended learning format. Video demonstrations can provide an enduring, on-demand, portable resource for revision, which can even be used at the bedside by learners. Such resources are cost-effectively scalable for large numbers of learners.

Super-Fine Attributes with Crowd Prototyping.

Recognising human attributes from surveillance footage is widely studied for attribute-based re-identification. However, most works assume coarse, expertly-defined categories, ineffective in describing challenging images. Such brittle representations are limited in descriminitive power and hamper the efficacy of learnt estimators. We aim to discover more relevant and precise subject descriptions, improving image retrieval and closing the semantic gap. Inspired by fine-grained and relative attributes, we introduce super-fine attributes, which now describe multiple, integral concepts of a single trait as multi-dimensional perceptual coordinates. Crowd prototyping facilitates efficient crowdsourcing of super-fine labels by pre-discovering salient perceptual concepts for prototype matching. We re-annotate gender, age and ethnicity traits from PETA, a highly diverse (19K instances, 8.7K identities) amalgamation of 10 re-id datasets including VIPER, CUHK and TownCentre. Employing joint attribute regression with the ResNet-152 CNN, we demonstrate substantially improved ranked retrieval performance with super-fine attributes in comparison to conventional binary labels, reporting up to a 11.2 and 14.8 percent mAP improvement for gender and age, further surpassed by ethnicity. We also find our 3 super-fine traits to outperform 35 binary attributes by 6.5 percent mAP for subject retrieval in a challenging zero-shot identification scenario.

Regional Variations in Shear Strength and Density of the Human Thoracic Vertebral Endplate and Trabecular Bone.

BACKGROUND: Previous studies investigated the overall mechanical strength of the vertebral body; however, limited information is available on the biomechanical properties of different regions within the vertebral endplate and cancellous bone. In addition, the correlation between mechanical strength and various density measurements has not been studied yet. METHODS: Thoracic (T10) vertebrae were harvested from fifteen human cadaveric spines (average age: 77 years old). Twelve cylindrical cores of 7.2 mm (diameter) by 3.2 mm (height) were prepared from each vertebral body. Shear was produced using a stainless steel tubular blade and measured with a load cell from a mechanical testing machine. Optical and bulk densities were calculated before mechanical testing. Apparent, material, and ash densities were measured after testing. RESULTS: Material density and shear strength increased from anterior to lateral regions of both endplate and cancellous bone. Endplate shear strength was significantly lower in the anterior (0.52 ± 0.08 MPa) than in the lateral region (2.72 ± 0.59 MPa) (p=0.017). Trabecular bone maximum load carrying capacity was 5 times higher in the lateral (12 ± 2.74 N) (p=0.09) and 4.5 times higher in the central (10 ± 2.24 N) (p=0.2) than in the anterior (2 ± 0.60 N) regions. Mechanical strength positively correlated with ash density, and even moreso with material density. CONCLUSION: Shear strength was the lowest at the anterior region and highest at the lateral region for both endplate and cancellous bone. Material density had the best correlation with mechanical strength. Newer spinal implants could optimize the loading in the lateral aspects of both endplate and cancellous bone to reduce the likelihood of screw loosening and the subsidence of disc replacement devices. This study was reviewed by the SUNY Downstate Medical Center IRB Committee; IRB#: 533603-2.

Myocardial fibrosis in chronic aortic regurgitation: molecular and cellular responses to volume overload.

BACKGROUND: Myocardial fibrosis is common in patients with chronic aortic regurgitation (AR). Experimentally, fibrosis with disproportionate noncollagen extracellular matrix (ECM) elements precedes and contributes to heart failure in AR. METHODS AND RESULTS: We assessed [3H]-glucosamine and [3H]-proline incorporation in ECM, variations in cardiac fibroblast (CF) gene expression, and synthesis of specific ECM proteins in CF cultured from rabbits with surgically induced chronic AR versus controls. To determine whether these variations are primary responses to AR, normal CF were exposed to mechanical strain that mimicked that of AR. Compared with normal CF, AR CF incorporated more glucosamine (1.8:1, P=0.001) into ECM, showed fibronectin gene upregulation (2.0:1, P=0.02), and synthesized more fibronectin (2:1 by Western blot, P<0.06; 1.5:1 by affinity chromatography, P=0.02). Proline incorporation was unchanged by AR (1.1:1, NS); collagen synthesis was unaffected (type I, 0.9:1; type III, 1.0:1, NS). Normal CF exposed to cyclical mechanical strain during culture showed parallel results: glucosamine incorporation increased with strain (2.1:1, P<0.001), proline incorporation was unaffected (1.1:1, NS), fibronectin gene expression (1.6:1, P=0.07) and fibronectin synthesis (Western analysis, 1.3:1, P<0.01; chromatography, 1.9:1, NS) were upregulated. CONCLUSIONS: In AR, CF produce abnormal proportions of noncollagen ECM, specifically fibronectin, with relatively little change in collagen synthesis. At least in part, this is a primary response to strain imposed on CF by AR. Further study must relate these findings to the pathogenesis of heart failure in AR.

Self-calibrating view-invariant gait biometrics.

We present a new method for viewpoint independent gait biometrics. The system relies on a single camera, does not require camera calibration, and works with a wide range of camera views. This is achieved by a formulation where the gait is self-calibrating. These properties make the proposed method particularly suitable for identification by gait, where the advantages of completely unobtrusiveness, remoteness, and covertness of the biometric system preclude the availability of camera information and specific walking directions. The approach has been assessed for feature extraction and recognition capabilities on the SOTON gait database and then evaluated on a multiview database to establish recognition capability with respect to view invariance. Moreover, tests on the multiview CASIA-B database, composed of more than 2270 video sequences with 65 different subjects walking freely along different walking directions, have been performed. The obtained results show that human identification by gait can be achieved without any knowledge of internal or external camera parameters with a mean correct classification rate of 73.6% across all views using purely dynamic gait features. The performance of the proposed method is particularly encouraging for application in surveillance scenarios.

The role of insulin glulisine to improve glycemic control in children with diabetes mellitus.

Glulisine (Apidra(®)) is a rapid-acting human insulin analog approved for use in children with diabetes mellitus ≥4 years of age. Management of children with type 1 diabetes has seen a shift in favor of mimicking normal physiological insulin responses with multiple daily injections or continuous subcutaneous insulin infusions (CSII). Few studies have compared the rapid-acting insulin analogs in this population but limited data indicate that glulisine is as effective as lispro when used in a basal-bolus regimen. This review appraises the current available studies and reviews on insulin glulisine in children. An extensive keyword search of 'insulin glulisine', 'insulin analogs', and 'Apidra' in the pediatric population was performed. These studies have suggested that glulisine is safe, well tolerated, and is an effective option in the diabetes armamentarium. Further studies are needed to determine its safety for use in CSII pumps in the pediatric population.

Cellular response of human cardiac fibroblasts to mechanically simulated aortic regurgitation.

Myocardial fibrosis has been identified in biopsy specimens from catheterization and valve replacement surgery in patients with severe chronic aortic regurgitation (AR). While characterization of these extracellular matrix (ECM) alterations has been incomplete in humans, fibrosis also has been identified in chronic severe experimentally created AR, in which ECM composition features abnormal fibronectin/glycoprotein production, with normal collagen content. Virtually identical ECM variations have been induced when normal rabbit cardiac fibroblasts (CF) are subjected in culture to cyclic mechanical strain mimicking that found in the left ventricle (LV) in severe AR. To determine whether the changes seen experimentally can be extrapolated to humans, we exposed normal human CF in culture to the mechanical strain employed in the experimental model to simulate severe AR (n=3 replications from 1 patient). CF were isolated from epicardial biopsy distant from diseased coronary arteries in a 38-year-old man with normal LV function and without prior myocardial infarction who was undergoing elective coronary artery bypass grafting. Gelatin Sepharose affinity chromatography (GSAC) and Western analysis were used to compare fibronectin expression in strained versus nonstrained normal human CF in tissue culture; Western analysis was used to compare type I collagen production. In AR-strained CF, fibronectin synthesis nominally increased [av 38% (Western) and 45% (GSAC)] relative to control; type I collagen synthesis was virtually unchanged. These results simulate those found experimentally and suggest that human CF, like rabbit CF, manifest abnormal compositional distribution of ECM proteins in AR.