When Multiple Conditions Converge: An Unusual Case of Infectious Aortitis in a Patient With Prurigo Nodularis and an Abdominal Aortic Aneurysm Endograft.

Infectious aortitis is a rare disease process that presents with mortality varying from 60% to 90%, even with aggressive treatment. This is a case involving a 69-year-old male who initially presented for acute encephalopathy. The patient's past medical history included coronary disease status post coronary bypass graft, abdominal aortic aneurysm status post endograft repair, prurigo nodularis, Tangier's disease, type 2 diabetes mellitus, and stage 3b chronic kidney disease. Initially, the work-up was unrevealing for a cause of the patient's acute encephalopathy. However, astute clinical evaluation led to the diagnosis of methicillin-sensitive Staphylococcus aureus (MSSA) bacteremia and abdominal infectious aortitis. Prurigo nodularis is a chronic dermatologic condition characterized by the development of intensely pruritic, firm nodules or bumps on the skin associated with itching and scratching. Prurigo nodularis itself does not directly result in bacteremia. However, in rare cases, severe and persistent scratching due to prurigo nodularis can lead to breaks in the skin, creating an entry point for bacteria to spread by the hematogenous route. Certainly, it is highly unusual to have a combination of prurigo nodularis, MSSA bacteremia, and abdominal aortic aneurysm endograft infection. Given the severity of these conditions individually, the combination presents a unique and challenging clinical scenario that requires prompt and coordinated management by a multidisciplinary team. This case report aims to provide new insights into the potential risk factors, clinical course, and management strategies for these combined conditions.

Characterization of the Emissions and Crystalline Silica Content of Airborne Dust Generated from Grinding Natural and Engineered Stones.

In this study, we systematically characterized the airborne dust generated from grinding engineered and natural stone products using a laboratory testing system designed and operated to collect representative respirable dust samples. Four stone samples tested included two engineered stones consisting of crystalline silica in a polyester resin matrix (formulations differed with Stones A having up to 90wt% crystalline silica and Stone B up to 50wt% crystalline silica), an engineered stone consisting of recycled glass in a cement matrix (Stone C), and a granite. Aerosol samples were collected by respirable dust samplers, total dust samplers, and a Micro-Orifice Uniform Deposit Impactor. Aerosol samples were analyzed by gravimetric analysis and x-ray diffraction to determine dust generation rates, crystalline silica generation rates, and crystalline silica content. Additionally, bulk dust settled on the floor of the testing system was analyzed for crystalline silica content. Real-time particle size distributions were measured using an Aerodynamic Particle Sizer. All stone types generated similar trimodal lognormal number-weighted particle size distributions during grinding with the most prominent mode at an aerodynamic diameter of about 2.0-2.3 µm, suggesting dust formation from grinding different stones is similar. Bulk dust from Stone C contained no crystalline silica. Bulk dust from Stone A, Stone B, and granite contained 60, 23, and 30wt% crystalline silica, respectively. In Stones A and B, the cristobalite form of crystalline silica was more plentiful than the quartz form. Only the quartz form was detected in granite. The bulk dust, respirable dust, and total dust for each stone had comparable amounts of crystalline silica, suggesting that crystalline silica content in the bulk dust could be representative of that in respirable dust generated during grinding. Granite generated more dust per unit volume of material removed than the engineered stones, which all had similar normalized dust generation rates. Stone A had the highest normalized generation rates of crystalline silica, followed by granite, Stone B, and Stone C (no crystalline silica), which likely leads to the same trend of respirable crystalline silica (RCS) exposure when working with these different stones. Manufacturing and adoption of engineered stone products with formulations such as Stone B or Stone C could potentially lower or eliminate RCS exposure risks. Combining all the effects of dust generation rate, size-dependent silica content, and respirable fraction, the highest normalized generation rate of RCS consistently occurs at 3.2-5.6 µm for all the stones containing crystalline silica. Therefore, removing particles in this size range near the generation sources should be prioritized when developing engineering control measures.

Caution on Using Tetrahydrofuran for Processing Crystalline Silica Samples From Engineered Stone for XRD Analysis.

We conducted laboratory experiments to investigate a suspected effect of tetrahydrofuran (THF) on quantifying crystalline silica in samples collected from working with engineered stone when THF is used to process samples prior to the X-ray diffraction (XRD) analysis. Two groups of samples from grinding either engineered stone or granite were simultaneously taken from a laboratory testing system, with one group of samples using THF for processing and another group using muffle furnace for ashing. For each stone type, we also tested four levels of respirable dust loading on the samples by varying the grinding time from 1 to 8 min. Statistical analysis of the experimental results on crystalline silica contents of the two groups of samples showed that the difference between the two methods was not significant (P ≥ 0.05) for the granite at all four levels of respirable dust loading and for the engineered stone at the two levels of respirable dust loading greater than 0.5 mg. However, the crystalline silica content from using THF processing was significantly lower (P = 0.001) than that from using muffle furnace ashing for engineered stone when the respirable dust loading levels were less than 0.5 mg. For the engineered stone dust samples with grinding times of 1 and 2 min, the average respirable dust loading was about 0.19 and 0.34 mg, respectively; while the crystalline silica content from using THF processing was 30.9 and 21.5% lower than that from using muffle furnace ashing, respectively. Since most full-shift samples from field assessments in this industry are expected to have respirable dust loading less than 0.5 mg, muffle furnace or radio frequency plasma ashing should be specified as the preferred sample processing method instead of the THF processing method for quantification of crystalline silica when engineered stone is expected to present to avoid artificially reduced silica content values, which are likely caused by the reactions between THF and the resins in engineered stone.

Point of care biliary ultrasound in the emergency department (BUSED) predicts final surgical management decisions.

Objectives: Gallstone disease is a common reason for emergency department (ED) presentation. Surgeons often prefer radiology department ultrasound (RUS) over point of care ultrasound (POCUS) because of perceived of unreliability. Our study was designed to test the hypothesis that POCUS is sufficient to guide the management of surgeons treating select cases of biliary disease as compared to RUS. Methods: This was a prospective cohort study. Patients who presented to the ED with abdominal pain and findings of biliary disease on POCUS were included. The surgeon was then presented the case with POCUS only and recorded their management decision. Patients then proceeded to RUS, were followed through their stay, and analysis was performed to analyze the proportion of patients where the introduction of the RUS changed the management plan. Results: 100 patients were included in this study, and all received both POCUS and RUS. Depending on the surgeons' POCUS based management decisions, the patients were divided into three groups: (1) surgery, (2) duct clearance, (3) no surgery. Total bilirubin was 34±22 mmol/L in the duct clearance group vs 8.4±6.5 mmol/L and 16±12 mmol/L in the surgery and no surgery groups, respectively (p<0.05). POCUS results showed 68 patients would have been offered surgery, 21 offered duct clearance, and 11 no surgery. In 90% of cases, the introduction of RUS did not change management. The acute care surgeons elected to operate on patients more frequently than other surgical subspecialties (p<0.05). Conclusions: This study showed that fewer than 10% of patients with biliary disease seen on POCUS had a change in surgical decision-making based on the addition of RUS imaging. In uncomplicated cases of biliary disease, relying on POCUS imaging for surgical decision-making has the potential to improve patient flow. Level of evidence: II Prospective Cohort Study.

The case for using mapped exonic non-duplicate reads when reporting RNA-sequencing depth: examples from pediatric cancer datasets.

BACKGROUND: The reproducibility of gene expression measured by RNA sequencing (RNA-Seq) is dependent on the sequencing depth. While unmapped or non-exonic reads do not contribute to gene expression quantification, duplicate reads contribute to the quantification but are not informative for reproducibility. We show that mapped, exonic, non-duplicate (MEND) reads are a useful measure of reproducibility of RNA-Seq datasets used for gene expression analysis. FINDINGS: In bulk RNA-Seq datasets from 2,179 tumors in 48 cohorts, the fraction of reads that contribute to the reproducibility of gene expression analysis varies greatly. Unmapped reads constitute 1-77% of all reads (median [IQR], 3% [3-6%]); duplicate reads constitute 3-100% of mapped reads (median [IQR], 27% [13-43%]); and non-exonic reads constitute 4-97% of mapped, non-duplicate reads (median [IQR], 25% [16-37%]). MEND reads constitute 0-79% of total reads (median [IQR], 50% [30-61%]). CONCLUSIONS: Because not all reads in an RNA-Seq dataset are informative for reproducibility of gene expression measurements and the fraction of reads that are informative varies, we propose reporting a dataset's sequencing depth in MEND reads, which definitively inform the reproducibility of gene expression, rather than total, mapped, or exonic reads. We provide a Docker image containing (i) the existing required tools (RSeQC, sambamba, and samblaster) and (ii) a custom script to calculate MEND reads from RNA-Seq data files. We recommend that all RNA-Seq gene expression experiments, sensitivity studies, and depth recommendations use MEND units for sequencing depth.

Reducing unnecessary testing in the emergency department: The case for INR and aPTT.

OBJECTIVE: Routine coagulation testing is rarely indicated in the emergency department. Our goal is to determine the combined effects of uncoupling routine coagulation testing (i.e., international normalized ratio [INR]; activated partial thromboplastin time [aPTT]), disseminating an educational module, and implementing a clinical decision support system (CDSS) on coagulation testing rates in two academic emergency departments. METHODS: A prospective pre-post study of INR-aPTT uncoupling, educational module distribution, and CDSS implementation in two academic emergency departments. All patients ages 18 years and older undergoing evaluation and treatment during the period of August 1, 2015, to November 30, 2017, were included. Primary outcome was coagulation testing utilization during the emergency department encounter. Secondary outcomes included associated costs, frequency of downstream testing, and frequency of blood transfusions. RESULTS: Uncoupling INR-aPTT testing combined with educational module distribution and CDSS implementation resulted in significantly decreased coupled INR-aPTT testing, with significantly increased selective INR and aPTT testing. Overall, the aggregate rate of coagulation testing declined for both INR and aPTT testing (48 tests/100 patients/day to 26 tests/100 patients/day). There was a significant decrease in associated daily costs (median cost per day: $1048.32 v. $601.68), realizing estimated annual savings of $163,023 Canadian dollars (CAD). There was no signal of increased downstream testing or patient blood product requirements. CONCLUSION: Compared to baseline practice patterns, our multimodal initiative significantly decreased coagulation testing, with meaningful cost savings and without evidence of patient harm. Clinicians and administrators now have a growing toolkit to target the plethora of low-value tests and treatments in emergency medicine.

Surgeon attitudes toward point of care ultrasound for biliary disease: a nationwide Canadian survey

Summary: Multiple studies confirm that point of care ultrasound (PoCUS) has a high sensitivity and specificity for cholelithiasis and cholecystitis. However, there is poor perceived reliability of biliary PoCUS by surgeons. This survey was performed to assess surgeons' opinions on using PoCUS in gallstone disease and barriers that exist for its institution. The majority (60.3%) of respondents reported a total lack of confidence in PoCUS for the diagnosis of biliary disease. Most felt the sensitivity of PoCUS was poor and had concerns about the user-dependent nature of the test and the lack of imaging details provided. If offered ideal clinical/laboratory findings with PoCUS results, only 4.7% of surgeons would definitely operate for unremitting biliary colic and 5.4% for cholecystitis. The ability to replicate findings independently increased confidence in clinical decision-making. Our findings suggest there is substantial distrust in biliary PoCUS but that specific ultrasound training for the surgical workforce may prove tremendously beneficial for its utilization.

The Canadian Medical Student Ultrasound Curriculum: A Statement From the Canadian Ultrasound Consensus for Undergraduate Medical Education Group.

OBJECTIVES: This study sought to establish by expert review a consensus-based, focused ultrasound curriculum, consisting of a foundational set of focused ultrasound skills that all Canadian medical students would be expected to attain at the end of the medical school program. METHODS: An expert panel of 21 point-of-care ultrasound and educational leaders representing 15 of 17 (88%) Canadian medical schools was formed and participated in a modified Delphi consensus method. Experts anonymously rated 195 curricular elements on their appropriateness to include in a medical school curriculum using a 5-point Likert scale. The group defined consensus as 70% or more experts agreeing to include or exclude an element. We determined a priori that no more than 3 rounds of voting would be performed. RESULTS: Of the 195 curricular elements considered in the first round of voting, the group reached consensus to include 78 and exclude 24. In the second round, consensus was reached to include 4 and exclude 63 elements. In our final round, with 1 additional item added to the survey, the group reached consensus to include an additional 3 and exclude 8 elements. A total of 85 curricular elements reached consensus to be included, with 95 to be excluded. Sixteen elements did not reach consensus to be included or excluded. CONCLUSIONS: By expert opinion-based consensus, the Canadian Ultrasound Consensus for Undergraduate Medical Education Group recommends that 85 curricular elements be considered for inclusion for teaching in the Canadian medical school focused ultrasound curricula.

Current State of Point-of-care Ultrasound Usage in Canadian Emergency Departments.

Background Point-of-care ultrasound (POCUS) has many applications in emergency medicine, which have been proven to improve patient outcomes. Training programs and well-established guidelines for its use are available, but Canadian adoption rates and attitudes toward this technology have not been recently assessed. Objectives This study aimed to provide a national assessment of the current use of POCUS in Canadian emergency departments (ED) including patterns of use, attitudes towards its role, descriptors of training experience, as well as barriers to increased utilization. Methods An electronic survey was sent to physician members of the Canadian Association of Emergency Physicians. The survey included questions related to demographics, attitudes towards POCUS, POCUS utilization, and barriers to POCUS use. Responses were statistically analyzed to identify significant associations. Results Responses demonstrated a strong association between POCUS training and amount of POCUS usage. Neither hospital type nor community type was associated with the degree of POCUS usage. POCUS was most widely adopted for Canadian Point of Care Ultrasound Society (CPOCUS) core applications and has increased since the last national survey. The most commonly reported barrier to increased POCUS adoption was the lack of training. Most physicians have formal POCUS training in core applications, and approximately one third have advanced training. Conclusions POCUS training and utilization appear to have increased since the last national assessment. This provides a foundation for future POCUS research.

Development of 3D printed mesofluidic devices to elute and concentrate DNA.

To understand structural variation for personal genomics, an extensive ensemble of large DNA molecules will be required to span large structural variations. Nanocoding, a whole-genome analysis platform, can analyze large DNA molecules for the construction of physical restriction maps of entire genomes. However, handling of large DNA is difficult and a system is needed to concentrate large DNA molecules, while keeping the molecules intact. Insert technology was developed to protect large DNA molecules during routine cell lysis and molecular biology techniques. However, eluting and concentrating DNA molecules has been difficult in the past. Utilizing 3D printed mesofluidic device, a proof of principle system was developed to elute and concentrate lambda DNA molecules at the interface between a solution and a poly-acrylamide roadblock. The matrix allowed buffer solution to move through the pores in the matrix; however, it slowed down the progression of DNA in the matrix, since the molecules were so large and the pore size was small. Using fluorescence intensity of the insert, 84% of DNA was eluted from the insert and 45% of DNA was recovered in solution from the eluted DNA. DNA recovered was digested with a restriction enzyme to determine that the DNA molecules remained full length during the elution and concentration of DNA.

Point-of-care biliary ultrasound in the emergency department (BUSED): implications for surgical referral and emergency department wait times.

BACKGROUND: Patients with uncomplicated biliary disease frequently present to the emergency department for assessment. To improve bedside clinical decision making, biliary point-of-care ultrasound (POCUS) in the emergency department has emerged as a diagnostic tool. The purpose of this study is to analyze the usefulness of POCUS in predicting the need for surgical intervention in biliary disease. METHODS: A retrospective study of patients visiting the emergency department who received a biliary POCUS from December 1, 2016 to July 15, 2017 was performed. The physician interpretations of the biliary POCUS scans were collected, as well as data from the electronic health records including lab values, the subsequent use of diagnostic imaging, surgical consultation or intervention, and 28 days follow-up for representation or complication. RESULTS: Two hundred and eighty-three patients were identified as having received biliary POCUS. Of the patients referred to general surgery who received biliary POCUS 43% received a cholecystectomy. For the outcome of cholecystectomy, the finding of gallstones on POCUS was 55% sensitive (95% CI 40% to 70%) and 92% specific (95% CI 87% to 95%). A sonographic Murphy's sign was 16% sensitive (95% CI 7% to 30%) but 95% specific (95% CI 92% to 97%) and, gallbladder wall thickness was 18% sensitive (95% CI 9% to 33%) and 98% specific (95% CI 95% to 99%). Patients who received POCUS but did not proceed to confirmatory radiology department imaging had a shorter length of stay (433 min ± 50 min vs. 309 min ± 30 min, P<0.001). DISCUSSION: Point-of-care biliary ultrasound performed by emergency physicians provides timely access to diagnostic information. Positive findings of gallstones and increased gallbladder wall thickness are highly predictive of the need for surgical intervention, and use of POCUS is associated with shorter ER visits. LEVEL OF EVIDENCE: Retrospective cohort study, level III.

Determining if DNA Stained with a Cyanine Dye Can Be Digested with Restriction Enzymes.

Visualization of DNA for fluorescence microscopy utilizes a variety of dyes such as cyanine dyes. These dyes are utilized due to their high affinity and sensitivity for DNA. In order to determine if the DNA molecules are full length after the completion of the experiment, a method is required to determine if the stained molecules are full length by digesting DNA with restriction enzymes. However, stained DNA may inhibit the enzymes, so a method is needed to determine what enzymes one could use for fluorochrome stained DNA. In this method, DNA is stained with a cyanine dye overnight to allow the dye and DNA to equilibrate. Next, stained DNA is digested with a restriction enzyme, loaded into a gel and electrophoresed. The experimental DNA digest bands are compared to an in silico digest to determine the restriction enzyme activity. If there is the same number of bands as expected, then the reaction is complete. More bands than expected indicate partial digestion and less bands indicate incomplete digestion. The advantage of this method is its simplicity and it uses equipment that a scientist would need for a restriction enzyme assay and gel electrophoresis. A limitation of this method is that the enzymes available to most scientists are commercially available enzymes; however, any restriction enzymes could be used.

The Role of Point of Care Ultrasound in the Injured Paediatric Patient.

The focus of this review is to examine the current state of paediatric Point of Care Ultrasound (POCUS) in the injured patient. POCUS has become useful across various medical specialties owing to its ease of use, reproducibility and non-ionizing qualities. Point of care ultrasound has advanced over the past years and has proven to be an extremely useful adjunct in the injured child. Discussion will center around the challenges on when and how to best utilize POCUS. This includes but is not limited to: detection of peritoneal free fluid, pneumothoraces, hemothoraces, pericardial effusions, a wide array of fractures, lung contusions and many other applications. Discussion will also be focused on the evolution of POCUS, as well as a discussion around the determination of training standards.

Point-of-care Ultrasound for Nonangulated Distal Forearm Fractures in Children: Test Performance Characteristics and Patient-centered Outcomes.

OBJECTIVES: Distal forearm fractures are the most common fracture type in children. Point-of-care-ultrasound (POCUS) is increasingly being used, and preliminary studies suggest that it offers an accurate approach to diagnosis. However, outcomes such as pain, satisfaction, and procedure duration have not been explored but may be salient to the widespread acceptance of this technology by caregivers and children. Our objectives were to examine the test performance characteristics of POCUS for nonangulated distal forearm injuries in children and compare POCUS to x-ray with respect to pain, caregiver satisfaction, and procedure duration. METHODS: We conducted a cross-sectional study involving children aged 4-17 years with a suspected nonangulated distal forearm fracture. Participants underwent both x-ray and POCUS assessment. The primary outcome was sensitivity between POCUS and x-ray, the reference standard. Secondary outcomes included self-reported pain using the Faces Pain Scale-Revised, caregiver satisfaction using a five-item Likert scale, and procedure duration. RESULTS: POCUS was performed in 169 children of whom 76 were diagnosed with a fracture including 61 buckle fractures. Sensitivity of POCUS for distal forearm fractures was 94.7% (95% confidence interval [CI] = 89.7-99.8) and specificity was 93.5% (95% CI = 88.6-98.5). POCUS was associated with a significantly lower median (interquartile range [IQR]) pain score compared to x-ray: 1 (0-2) versus 2 (1-3), respectively (median difference = 0.5; 95% CI = 0.5-1; p < 0.001) and no significant difference in median (IQR) caregiver satisfaction score: 5 (0) versus 5 (4-5), respectively (median difference = 0, 95% CI = 0, p = 1.0). POCUS was associated with a significantly lower median (IQR) procedure duration versus x-ray: 1.5 (0.8-2.2) minutes versus 27 (15-58) minutes, respectively (median difference = 34.1, 95% CI = 26.8-41.5, p < 0.001). CONCLUSIONS: Our findings suggest that POCUS assessment of distal forearm injuries in children is accurate, timely, and associated with low levels of pain and high caregiver satisfaction.

Focused Transesophageal Echocardiography by Emergency Physicians is Feasible and Clinically Influential: Observational Results from a Novel Ultrasound Program.

BACKGROUND: Emergency physicians frequently employ transthoracic echocardiography (TTE) to assist in diagnosis and therapy for patients with circulatory failure or arrest. In critically ill patients, transesophageal echocardiography (TEE) offers several advantages over TTE, including reliable, continuous image acquisition and superior image quality. Despite these advantages, TEE is not widely used by emergency physicians. OBJECTIVE: Report the feasibility, findings, and clinical influence observed from the first described TEE program implemented in an emergency department (ED) point-of-care ultrasound program. METHODS: This was a retrospective review of all ED TEE examinations carried out between February 1, 2013 and January 30, 2015. TEE images and report details (including operator, indication, findings, and clinical recommendation[s]) were exported from the institutional ultrasound archive and analyzed. The electronic chart of each patient was subsequently reviewed for the presence of any complications related to the examination and their clinical course in the hospital. RESULTS: A total of 54 TEE examinations were performed by 12 different emergency physicians. All patients were intubated, and 98% of the examinations were determinate. The most common indications for TEE were intracardiac arrest care in 23 (43%), postarrest management in 14 (26%), and undifferentiated hypotension in 16 (40%). Probe insertion was successful in all cases. TEE imparted a diagnostic influence in 78% of cases and impacted therapeutic decisions in 67% of cases. CONCLUSION: From our analysis of a single-center experience, ED-based TEE showed a high degree of feasibility and clinical utility, with a diagnostic and therapeutic influence seen in the majority of cases. Focused TEE demonstrated strongest uptake among intubated patients with either undifferentiated shock or cardiac arrest.

Aerosol Emission Monitoring and Assessment of Potential Exposure to Multi-walled Carbon Nanotubes in the Manufacture of Polymer Nanocomposites.

Recent animal studies have shown that carbon nanotubes (CNTs) may pose a significant health risk to those exposed in the workplace. To further understand this potential risk, effort must be taken to measure the occupational exposure to CNTs. Results from an assessment of potential exposure to multi-walled carbon nanotubes (MWCNTs) conducted at an industrial facility where polymer nanocomposites were manufactured by an extrusion process are presented. Exposure to MWCNTs was quantified by the thermal-optical analysis for elemental carbon (EC) of respirable dust collected by personal sampling. All personal respirable samples collected (n = 8) had estimated 8-h time weighted average (TWA) EC concentrations below the limit of detection for the analysis which was about one-half of the recommended exposure limit for CNTs, 1 µg EC/m(3) as an 8-h TWA respirable mass concentration. Potential exposure sources were identified and characterized by direct-reading instruments and area sampling. Area samples analyzed for EC yielded quantifiable mass concentrations inside an enclosure where unbound MWCNTs were handled and near a pelletizer where nanocomposite was cut, while those analyzed by electron microscopy detected the presence of MWCNTs at six locations throughout the facility. Through size selective area sampling it was identified that the airborne MWCNTs present in the workplace were in the form of large agglomerates. This was confirmed by electron microscopy where most of the MWCNT structures observed were in the form of micrometer-sized ropey agglomerates. However, a small fraction of single, free MWCNTs was also observed. It was found that the high number concentrations of nanoparticles, ~200000 particles/cm(3), present in the manufacturing facility were likely attributable to polymer fumes produced in the extrusion process.