Determination of Endovaginal Ultrasound Proficiency and Learning Curve Among Emergency Medicine Trainees.

OBJECTIVES: Performing and interpreting endovaginal ultrasound is an important skill used during the evaluation of obstetric and gynecologic emergencies. This study aims to describe the level of proficiency and confidence achieved after performing 25 endovaginal examinations. METHODS: This is a prospective study at a single urban academic emergency department. Participants performed a minimum of 25 endovaginal ultrasounds under the supervision of a point-of-care ultrasound expert. Anatomical structures were identified by the expert under ultrasound prior to each session. Each examination was scored for agreement of findings between the participant and expert. The data were used to develop a performance curve identifying when proficiency was achieved, where experiential benefit diminished, and when participants felt confident. RESULTS: A total of 1117 endovaginal ultrasound examinations were performed by 50 participants. Agreement after 25 examinations was highest (>95%) for probe insertion and preparation, bladder and uterus identification, and directionality. Agreement was lowest for identification of the ovaries (76%). Experiential benefit plateaus occurred earliest (10 exams) for preparation and insertion followed by bladder identification and directionality. Surprisingly, ovarian experiential benefit plateaued at 16 exams. Participant confidence improved overall and was lowest for the identification of ovaries and abnormal pelvic anatomy. CONCLUSIONS: There is a significant learning curve when performing endovaginal ultrasound. Our data do not support the use of 25 examinations as a minimum standard for identification of the ovaries or abnormal ovarian pathology.

Ribosome profiling reveals post-transcriptional buffering of divergent gene expression in yeast.

Understanding the patterns and causes of phenotypic divergence is a central goal in evolutionary biology. Much work has shown that mRNA abundance is highly variable between closely related species. However, the extent and mechanisms of post-transcriptional gene regulatory evolution are largely unknown. Here we used ribosome profiling to compare transcript abundance and translation efficiency in two closely related yeast species (S. cerevisiae and S. paradoxus). By comparing translation regulatory divergence to interspecies differences in mRNA sequence features, we show that differences in transcript leaders and codon bias substantially contribute to divergent translation. Globally, we find that translation regulatory divergence often buffers species differences in mRNA abundance, such that ribosome occupancy is more conserved than transcript abundance. We used allele-specific ribosome profiling in interspecies hybrids to compare the relative contributions of cis- and trans-regulatory divergence to species differences in mRNA abundance and translation efficiency. The mode of gene regulatory divergence differs for these processes, as trans-regulatory changes play a greater role in divergent mRNA abundance than in divergent translation efficiency. Strikingly, most genes with aberrant transcript abundance in F1 hybrids (either over- or underexpressed compared to both parent species) did not exhibit aberrant ribosome occupancy. Our results show that interspecies differences in translation contribute substantially to the evolution of gene expression. Compensatory differences in transcript abundance and translation efficiency may increase the robustness of gene regulation.

Development and Optimization of an Unbiased, Metagenomics-Based Pathogen Detection Workflow for Infectious Disease and Biosurveillance Applications.

Rapid, specific, and sensitive identification of microbial pathogens is critical to infectious disease diagnosis and surveillance. Classical culture-based methods can be applied to a broad range of pathogens but have long turnaround times. Molecular methods, such as PCR, are time-effective but are not comprehensive and may not detect novel strains. Metagenomic shotgun next-generation sequencing (NGS) promises specific identification and characterization of any pathogen (viruses, bacteria, fungi, and protozoa) in a less biased way. Despite its great potential, NGS has yet to be widely adopted by clinical microbiology laboratories due in part to the absence of standardized workflows. Here, we describe a sample-to-answer workflow called PanGIA (Pan-Genomics for Infectious Agents) that includes simplified, standardized wet-lab procedures and data analysis with an easy-to-use bioinformatics tool. PanGIA is an end-to-end, multi-use workflow that can be used for pathogen detection and related applications, such as biosurveillance and biothreat detection. We performed a comprehensive survey and assessment of current, commercially available wet-lab technologies and open-source bioinformatics tools for each workflow component. The workflow includes total nucleic acid extraction from clinical human whole blood and environmental microbial forensic swabs as sample inputs, host nucleic acid depletion, dual DNA and RNA library preparation, shotgun sequencing on an Illumina MiSeq, and sequencing data analysis. The PanGIA workflow can be completed within 24 h and is currently compatible with bacteria and viruses. Here, we present data from the development and application of the clinical and environmental workflows, enabling the specific detection of pathogens associated with bloodstream infections and environmental biosurveillance, without the need for targeted assay development.

How Many Ultrasound Examinations Are Necessary to Gain Proficiency in Accurately Identifying the Nerves of the Brachial Plexus at the Level of the Interscalene Space?

INTRODUCTION: There has been a trend toward the use of alternative treatments to opioids for adequate pain management. This has paralleled a growing interest in the utilization of bedside point-of-care ultrasonography to guide placement of regional anesthesia in the emergency department. The purpose of this study was to establish the number of supervised examinations required for an emergency medicine resident to gain proficiency in accurately locating and identifying the nerves of the brachial plexus at the level of the interscalene space. METHODS: Proficiency was defined as the number of attempts a resident required to accurately locate and identify the nerves of the brachial plexus on 10 separate, consecutive examinations. Didactic education was provided prior to the study and residents also participated in two instructional hands-on ultrasound examinations prior to the commencement of initial data collection. Count data are summarized using medians, means, and ranges. Random effects negative binomial regression was used for modeling panel count data where negative coefficients indicate increase in proficiency. RESULTS: A total of 24 emergency medicine residents were enrolled in the study. Fourteen males and ten females participated. There were nine PGY-1 residents (37.5%), nine PGY-2 residents (37.5%), and six PGY-3 residents (25%). The median number of required supervised attempts and range for correctly performing both steps in the identification of the nerves of the brachial plexus was 2 (range 2-12). The median starting confidence level was 2 (range 1-4), and the median ending confidence level was 4 (range 1-5). Increases in confidence from start to finish were found to be statistically significant (P < 0.001). CONCLUSION: Emergency medicine residents are easily adept in the identification of the nerves of the brachial plexus at the level of the interscalene space following two supervised examinations. Residents made steady gains in confidence and proficiency throughout the study; statistical analysis found a significant association between the two.