Utility of point of care ultrasound for identifying dental abscesses in emergency department patients presenting with dental pain

Introduction: Computed tomography (CT) is the current gold standard for diagnosing dental abscesses in the Emergency Department (ED). There are limitations to using CT, including high cost, radiation exposure, and lengthy time to diagnosis. Point of Care Ultrasound (POCUS) is an alternative imaging modality that does not have these limitations, and is already used to diagnose other soft tissue abscesses. The efficacy of POCUS for diagnosing suspected dental abscesses has never been investigated. The purpose of this project is to compare the utility of POCUS to CT in diagnosing suspected dental abscesses in the ED. Methods: A convenience sample of patients presenting to the ED with dental pain were enrolled into a prospective observational cohort study design, when trained providers were available. Patients were eligible for enrollment after a CT was ordered. The ability of POCUS to identify dental abscesses was compared to CT in each patient. Data was collected using REDCap, and analyzed testing for non-inferiority. Results: Preliminary results indicate that POCUS is non-inferior to CT at diagnosing dental abscesses (p=0.002, n=31). Additionally, the time to diagnosis is significantly shorter for POCUS compared to CT (p\u3c0.0001). Conclusions: These results suggest that POCUS may be an adequate tool for evaluating suspected dental abscesses in the ED. Due to decreased time to diagnosis, patients with suspected dental abscesses receiving POCUS instead of CT as an initial diagnostic imaging study may receive treatment and disposition significantly earlier. This could potentially lead to improved outcomes in patients

A Three-dimensional Printed Low-cost Anterior Shoulder Dislocation Model for Ultrasound-guided Injection Training.

Anterior shoulder dislocations are the most common, large joint dislocations that present to the emergency department (ED). Numerous studies support the use of intraarticular local anesthetic injections for the safe, effective, and time-saving reduction of these dislocations. Simulation training is an alternative and effective method for training compared to bedside learning. There are no commercially available ultrasound-compatible shoulder dislocation models. We utilized a three-dimensional (3D) printer to print a model that allows the visualization of the ultrasound anatomy (sonoanatomy) of an anterior shoulder dislocation. We utilized an open-source file of a shoulder, available from embodi3D® (Bellevue, WA, US). After approximating the relative orientation of the humerus to the glenoid fossa in an anterior dislocation, the humerus and scapula model was printed with an Ultimaker-2 Extended+ 3D® (Ultimaker, Cambridge, MA, US) printer using polylactic acid filaments. A 3D model of the external shoulder anatomy of a live human model was then created using Structure Sensor®(Occipital, San Francisco, CA, US), a 3D scanner. We aligned the printed dislocation model of the humerus and scapula within the resultant external shoulder mold. A pourable ballistics gel solution was used to create the final shoulder phantom. The use of simulation in medicine is widespread and growing, given the restrictions on work hours and a renewed focus on patient safety. The adage of see one, do one, teach one is being replaced by deliberate practice. Simulation allows such training to occur in a safe teaching environment. The ballistic gel and polylactic acid structure effectively reproduced the sonoanatomy of an anterior shoulder dislocation. The 3D printed model was effective for practicing an in-plane ultrasound-guided intraarticular joint injection. 3D printing is effective in producing a low-cost, ultrasound-capable model simulating an anterior shoulder dislocation. Future research will determine whether provider confidence and the use of intraarticular anesthesia for the management of shoulder dislocations will improve after utilizing this model

The Effect of Display Size on Ultrasound Interpretation

Purpose: To assess how display size affects providers’ abilities to accurately interpret ultrasound (U/S) videos. U/S has become essential for patient evaluation in the emergency setting. Although newer devices that are smaller in size and affordable place the technology within the pockets of practitioners, it is necessary to assess how smaller size may impact image quality. Methods: The target learner population for this study includes all practitioners who perform point of care U/S. A prospective convenience sample of emergency providers were randomized to begin on either a phone-sized screen or a laptop-sized screen. Participants answered Yes or No in response to whether they identified free fluid, above and/or below the diaphragm on each of 50 unique right upper quadrant U/S videos, with 25 displayed per device. Researchers collected data on the speed of interpretation and participants\u27 experiences. Results and Conclusions: Prior to study initiation, 50% of participants felt display size would affect accuracy, 42.3% were unsure, and 7.7% felt it would not (n=52). The accuracy of interpretation for phone versus laptop display was 87.3% and 87.6%, respectively (p=0.84). Mean time spent with phone versus laptop display was 293s and 290s, respectively (p=0.66). Upon study completion, 48.1% of participants believed display size affected their ability to interpret the videos, 38.5% felt it did not, and 13.5% were unsure. The results of this study show no significant statistical difference in the accuracy of interpretation between screen sizes

The Clicker Study

Purpose: A recent study in orthopedics showed that clicker-based learning was more effective than traditional feedback when teaching procedures. We sought to determine whether this principle is applicable to ultrasound skills. Methods: Our prospective randomized control trial used a population of new ultrasound learners. Exclusion criteria included previous ultrasound experience of more than one hour. Students were shown an instructional video on the Focused Assessment with Sonography in Trauma (FAST) exam and randomized to receive clicker or scripted feedback. Each student performed the FAST exam once without feedback, then with either scripted or clicker-based feedback. They were timed and scored on 18 microskills. Results and Conclusions: 45 students were enrolled in the study, with 6 excluded from analysis. This included 24 premedical and 15 medical students. No significant differences were observed between groups for time or accuracy on the FAST exam. Among medical students, there was a trend toward faster results in the clicker group (mean=83 seconds) than the script group (mean=103 seconds) (p=0.22). Among undergraduates, there was a trend toward higher accuracy in the script group (mean=100%) than the clicker group (mean=95%) (p=0.068) and towards faster performance (mean=103 seconds) than the clicker group (mean=121 seconds) (p=0.38). Although no significant differences were observed, there seemed to be a trend toward faster performance with clicker feedback among medical students and faster and more accurate performance with scripted feedback among premedical students. This may be an area for future study

The Chop Gene Contains an Element for the Positive Regulation of the Mitochondrial Unfolded Protein Response

We have previously reported on the discovery of a mitochondrial specific unfolded protein response (mtUPR) in mammalian cells, in which the accumulation of unfolded protein within the mitochondrial matrix results in the transcriptional activation of nuclear genes encoding mitochondrial stress proteins such as chaperonin 60, chaperonin 10, mtDnaJ, and ClpP, but not those encoding stress proteins of the endoplasmic reticulum (ER) or the cytosol. Analysis of the chaperonin 60/10 bidirectional promoter showed that the CHOP element was required for the mtUPR and that the transcription of the chop gene is activated by mtUPR. In order to investigate the role of CHOP in the mtUPR, we carried out a deletion analysis of the chop promoter. This revealed that the transcriptional activation of the chop gene by mtUPR is through an AP-1 (activator protein-1) element. This site lies alongside an ERSE element through which chop transcription is activated in response to the ER stress response (erUPR). Thus CHOP can be induced separately in response to 2 different stress response pathways. We also discuss the potential signal pathway between mitochondria and the nucleus for the mtUPR

Cholera Toxin B Subunits Assemble into Pentamers - Proposition of a Fly-Casting Mechanism

The cholera toxin B pentamer (CtxB5), which belongs to the AB5 toxin family, is used as a model study for protein assembly. The effect of the pH on the reassembly of the toxin was investigated using immunochemical, electrophoretic and spectroscopic methods. Three pH-dependent steps were identified during the toxin reassembly: (i) acquisition of a fully assembly-competent fold by the CtxB monomer, (ii) association of CtxB monomer into oligomers, (iii) acquisition of the native fold by the CtxB pentamer. The results show that CtxB5 and the related heat labile enterotoxin LTB5 have distinct mechanisms of assembly despite sharing high sequence identity (84%) and almost identical atomic structures. The difference can be pinpointed to four histidines which are spread along the protein sequence and may act together. Thus, most of the toxin B amino acids appear negligible for the assembly, raising the possibility that assembly is driven by a small network of amino acids instead of involving all of them

Adhesion Molecules Associated with Female Genital Tract Infection

Altres ajuts: Marie Curie Career Integration Grant i una beca Fundació Dexeus Salut de la DonaEfforts to develop vaccines that can elicit mucosal immune responses in the female genital tract against sexually transmitted infections have been hampered by an inability to measure immune responses in these tissues. The differential expression of adhesion molecules is known to confer site-dependent homing of circulating effector T cells to mucosal tissues. Specific homing molecules have been defined that can be measured in blood as surrogate markers of local immunity (e.g. α4β7 for gut). Here we analyzed the expression pattern of adhesion molecules by circulating effector T cells following mucosal infection of the female genital tract in mice and during a symptomatic episode of vaginosis in women. While CCR2, CCR5, CXCR6 and CD11c were preferentially expressed in a mouse model of Chlamydia infection, only CCR5 and CD11c were clearly expressed by effector T cells during bacterial vaginosis in women. Other homing molecules previously suggested as required for homing to the genital mucosa such as α4β1 and α4β7 were also differentially expressed in these patients. However, CD11c expression, an integrin chain rarely analyzed in the context of T cell immunity, was the most consistently elevated in all activated effector CD8+ T cell subsets analyzed. This molecule was also induced after systemic infection in mice, suggesting that CD11c is not exclusive of genital tract infection. Still, its increase in response to genital tract disorders may represent a novel surrogate marker of mucosal immunity in women, and warrants further exploration for diagnostic and therapeutic purposes

Connectivity within and among a Network of Temperate Marine Reserves

Networks of marine reserves are increasingly being promoted as a means of conserving marine biodiversity. One consideration in designing systems of marine reserves is the maintenance of connectivity to ensure the long-term persistence and resilience of populations. Knowledge of connectivity, however, is frequently lacking during marine reserve design and establishment. We characterise patterns of genetic connectivity of 3 key species of habitat-forming macroalgae across an established network of temperate marine reserves on the east coast of Australia and the implications for adaptive management and marine reserve design. Connectivity varied greatly among species. Connectivity was high for the subtidal macroalgae Ecklonia radiata and Phyllospora comosa and neither species showed any clear patterns of genetic structuring with geographic distance within or among marine parks. In contrast, connectivity was low for the intertidal, Hormosira banksii, and there was a strong pattern of isolation by distance. Coastal topography and latitude influenced small scale patterns of genetic structure. These results suggest that some species are well served by the current system of marine reserves in place along this temperate coast but it may be warranted to revisit protection of intertidal habitats to ensure the long-term persistence of important habitat-forming macroalgae. Adaptively managing marine reserve design to maintain connectivity may ensure the long-term persistence and resilience of marine habitats and the biodiversity they support

Antiplatelet therapy with aspirin, clopidogrel, and dipyridamole versus clopidogrel alone or aspirin and dipyridamole in patients with acute cerebral ischaemia (TARDIS): a randomised, open-label, phase 3 superiority trial

Background: Intensive antiplatelet therapy with three agents might be more effective than guideline treatment for preventing recurrent events in patients with acute cerebral ischaemia. We aimed to compare the safety and efficacy of intensive antiplatelet therapy (combined aspirin, clopidogrel, and dipyridamole) with that of guideline-based antiplatelet therapy. Methods: We did an international, prospective, randomised, open-label, blinded-endpoint trial in adult participants with ischaemic stroke or transient ischaemic attack (TIA) within 48 h of onset. Participants were assigned in a 1:1 ratio using computer randomisation to receive loading doses and then 30 days of intensive antiplatelet therapy (combined aspirin 75 mg, clopidogrel 75 mg, and dipyridamole 200 mg twice daily) or guideline-based therapy (comprising either clopidogrel alone or combined aspirin and dipyridamole). Randomisation was stratified by country and index event, and minimised with prognostic baseline factors, medication use, time to randomisation, stroke-related factors, and thrombolysis. The ordinal primary outcome was the combined incidence and severity of any recurrent stroke (ischaemic or haemorrhagic; assessed using the modified Rankin Scale) or TIA within 90 days, as assessed by central telephone follow-up with masking to treatment assignment, and analysed by intention to treat. This trial is registered with the ISRCTN registry, number ISRCTN47823388. Findings: 3096 participants (1556 in the intensive antiplatelet therapy group, 1540 in the guideline antiplatelet therapy group) were recruited from 106 hospitals in four countries between April 7, 2009, and March 18, 2016. The trial was stopped early on the recommendation of the data monitoring committee. The incidence and severity of recurrent stroke or TIA did not differ between intensive and guideline therapy (93 [6%] participants vs 105 [7%]; adjusted common odds ratio [cOR] 0·90, 95% CI 0·67–1·20, p=0·47). By contrast, intensive antiplatelet therapy was associated with more, and more severe, bleeding (adjusted cOR 2·54, 95% CI 2·05–3·16, p<0·0001). Interpretation: Among patients with recent cerebral ischaemia, intensive antiplatelet therapy did not reduce the incidence and severity of recurrent stroke or TIA, but did significantly increase the risk of major bleeding. Triple antiplatelet therapy should not be used in routine clinical practice