Non-Malignant Cardiac Tumors

Cardiac tumors represent an unusual clinical problem in that they are often discovered as an incidental finding during a routine echocardiogram or in the course of a work-up for a source of embolism. Malignant tumors of the heart are either defined as primary or metastatic from an extra-cardiac primary source—regardless, the prognosis is poor. However, there are several cardiac tumors that are characterized as being non-malignant with regard to their tumor biology, but their tendencies to cause embolic or obstructive complications can be just as catastrophic despite a lack of invasiveness or potential to metastasize. The purpose of this chapter is to review the common types of non-malignant cardiac tumors with regard to their incidence, presentation, potential for complications, and management—with emphasis on surgical indications and techniques

Locomotor adaptability in persons with unilateral transtibial amputation

Background Locomotor adaptation enables walkers to modify strategies when faced with challenging walking conditions. While a variety of neurological injuries can impair locomotor adaptability, the effect of a lower extremity amputation on adaptability is poorly understood. Objective Determine if locomotor adaptability is impaired in persons with unilateral transtibial amputation (TTA). Methods The locomotor adaptability of 10 persons with a TTA and 8 persons without an amputation was tested while walking on a split-belt treadmill with the parallel belts running at the same (tied) or different (split) speeds. In the split condition, participants walked for 15 minutes with the respective belts moving at 0.5 m/s and 1.5 m/s. Temporal spatial symmetry measures were used to evaluate reactive accommodations to the perturbation, and the adaptive/de-adaptive response. Results Persons with TTA and the reference group of persons without amputation both demonstrated highly symmetric walking at baseline. During the split adaptation and tied post-adaptation walking both groups responded with the expected reactive accommodations. Likewise, adaptive and de-adaptive responses were observed. The magnitude and rate of change in the adaptive and de-adaptive responses were similar for persons with TTA and those without an amputation. Furthermore, adaptability was no different based on belt assignment for the prosthetic limb during split adaptation walking. Conclusions Reactive changes and locomotor adaptation in response to a challenging and novel walking condition were similar in persons with TTA to those without an amputation. Results suggest persons with TTA have the capacity to modify locomotor strategies to meet the demands of most walking conditions despite challenges imposed by an amputation and use of a prosthetic limb

A Pre-mRNA–Associating Factor Links Endogenous siRNAs to Chromatin Regulation

In plants and fungi, small RNAs silence gene expression in the nucleus by establishing repressive chromatin states. The role of endogenous small RNAs in metazoan nuclei is largely unknown. Here we show that endogenous small interfering RNAs (endo-siRNAs) direct Histone H3 Lysine 9 methylation (H3K9me) in Caenorhabditis elegans. In addition, we report the identification and characterization of nuclear RNAi defective (nrde)-1 and nrde-4. Endo-siRNA–driven H3K9me requires the nuclear RNAi pathway including the Argonaute (Ago) NRDE-3, the conserved nuclear RNAi factor NRDE-2, as well as NRDE-1 and NRDE-4. Small RNAs direct NRDE-1 to associate with the pre-mRNA and chromatin of genes, which have been targeted by RNAi. NRDE-3 and NRDE-2 are required for the association of NRDE-1 with pre-mRNA and chromatin. NRDE-4 is required for NRDE-1/chromatin association, but not NRDE-1/pre-mRNA association. These data establish that NRDE-1 is a novel pre-mRNA and chromatin-associating factor that links small RNAs to H3K9 methylation. In addition, these results demonstrate that endo-siRNAs direct chromatin modifications via the Nrde pathway in C. elegans

Variability in Anesthesia Models of Care in Cardiac Surgery

The operating room in a cardiothoracic surgical case is a complex environment, with multiple handoffs often required by staffing changes, and can be variable from program to program. This study was done to characterize what types of practitioners provide anesthesia during cardiac operations to determine the variability in this aspect of care. A survey was sent out via a list serve of members of the cardiac surgical team. Responses from 40 programs from a variety of countries showed variability across every dimension requested of the cardiac anesthesia team. Given that anesthesia is proven to have an influence on the outcome of cardiac procedures, this study indicates the opportunity to further study how this variability influences outcomes and to identify best practices

A structured teaching curriculum for medical students improves their performance on the National Board of Medical Examiners shelf examination in surgery.

BACKGROUND: The aim of this study was to evaluate the effect of a resident-driven, student taught educational curriculum on the medical students\u27 performance on the National Board of Medical Examiners surgery subject examination (NBME). METHODS: On daily morning rounds, medical students or the chief resident delivered preassigned brief presentations on 1 or 2 of the 30 common surgical topics selected for the curriculum. An initial assessment of student knowledge and an end-rotation in-house examination (multiple choice question examination) were conducted. The mean scores on the NBME examination were compared between students in teams using this teaching curriculum and those without it. RESULTS: A total of 57 third-year medical students participated in the study. The mean score on the in-house postclerkship multiple choice question examination was increased by 23.5% (P \u3c .05). The mean NBME scores were significantly higher in the students who underwent the teaching curriculum when compared with their peers who were not exposed to the teaching curriculum (78 vs 72, P \u3c .05). CONCLUSION: The implementation of a resident-driven structured teaching curriculum improved performance of medical students on the NBME examination

Is there a place for medical students as teachers in the education of junior residents?

BACKGROUND: The aim of this study was to investigate a novel resident education model that turns the traditional surgical hierarchy upside down, termed a reverse peer-assisted learning curriculum. METHODS: Thirty surgical topics were randomized between medical students and chief residents on each clinical team, with 1 topic being presented briefly during morning rounds. An exam evaluating junior residents\u27 knowledge of these topics was administered before and after 1 month of presentations. A questionnaire was distributed to evaluate the junior residents\u27 perceptions of this teaching model. RESULTS: Thirty-four residents participated. There was a significant improvement in the mean examination score (54 vs 74, P \u3c .05). No significant difference was noted in the mean score differentials of topics presented by either the medical students or the chief resident (21 vs 18, P = .22). More than 80% of the residents responded positively about the effectiveness of this exercise and agreed that they would like to see this model used on other services. CONCLUSIONS: This study confirms the hypothesis that medical students can teach surgical topics to junior residents at least as effectively as their chief residents

Corvallis Fire Department strategic plan 2009-2014

25 pp. Tables, figures, illus., appendices

Cationic contrast agents improve quantification of glycosaminoglycan (GAG) content by contrast enhanced CT imaging of cartilage

Minimally invasive and non-destructive methods to quantify glycosaminoglycans (GAGs) in articular cartilage extracellular matrix are of significant interest for the biochemical analysis of cartilage and diagnosis and tracking of osteoarthritis in vivo. Here, we report the use of cationic iodinated contrast agents in comparison to conventional anionic contrast agents for the quantitative monitoring of GAG concentrations with peripheral quantitative computed tomography. Using an ex vivo bovine osteochondral plug model, the cationic contrast agents were evaluated for their ability to distribute into articular cartilage and generate a positive relationship with GAG content. The cationic agents resulted in much higher equilibrium X-ray attenuations in cartilage extracellular matrix (ECM) than anionic agents. Experiments with samples subjected to enzymatic GAG degradation demonstrated that the cationic agents were up to five times more sensitive (p = 0.0001) to changes in GAG content and had a 24% higher correlation (p = 0.002) compared to the anionic agent (R2 = 0.86, p < 0.0001 compared with R2 = 0.62, p = 0.004). The natural inhomogeneous distribution of GAGs in the ECM could clearly be identified in undegraded samples.Chemistry and Chemical Biolog