Accelerated Measurement of Carotid Plaque Volume Using Artificial Intelligence Enhanced 3D Ultrasound.

BACKGROUND: Carotid plaque volume (CPV) can be measured by 3D ultrasound and may be a better predictor of stroke than stenosis, but analysis time limits clinical utility. This study tested the accuracy, reproducibility, and time saved of using an artificial intelligence (AI) derived semiautomatic software to measure CPV ("auto-CPV"). METHODS: Three-dimensional (3D) ultrasound images for 121 individuals were analyzed by 2 blinded operators to measure auto-CPV. Corresponding endarterectomy specimen volumes were calculated by the validated saline suspension technique. Inter-rater and intrarater agreement plus accuracy compared with the volume of the endarterectomized plaque were calculated. Measurement times were compared with previous manual CPV measurement. RESULTS: The mean difference between auto-CPV and surgical volume was small at (±s.d.) [95% confidence interval [CI]] 0.06 (0.24) [-0.41 to 0.54] cm3. The intraclass correlation (ICC) was strong at 0.91; 95% CI 0.86-0.94. Interobserver and intraobserver error was low with mean difference (±s.d.) [95%CI] 0.01 (0.26) [-0.5 to 0.5] cm3 and 0.03 (0.19) [-0.35 to 0.40] cm3 respectively. Both showed excellent ICC with narrow confidence intervals, ICC = 0.90; 95% CI (0.85-0.94) and ICC = 0.95; 95% CI (0.92-0.96). Auto-CPV measurement took 43% the time of manual planimetry; median (IQR) 05:39 (01:58) minutes compared to 13:05 (04:15) minutes, Wilcoxon rank-sum test, P < 0.01. CONCLUSIONS: Auto-CPV assessment is accurate, reproducible, and significantly faster than manual planimetry. Improved feasibility means that the utility of CPV can be assessed in large population studies to stratify risk in asymptomatic carotid disease or assess response to medical treatment.

Improving duplex ultrasound methods for diagnosing functional popliteal artery entrapment syndrome.

OBJECTIVES: Popliteal artery entrapment syndrome (PAES) is a rare condition where musculoskeletal structures compress the popliteal artery (POPA) leading to vascular compromise. This study investigates the effect of dynamic plantar- and dorsi-flexion loading on POPA hemodynamic parameters to develop a robust diagnostic ultrasound-based protocol for diagnosing functional PAES. METHODS: Healthy individuals (n = 20), recreational athletes (n = 20), and symptomatic (n = 20) PAES patients were consented. Triplex ultrasound imaging of lower limb arteries was performed (n = 120 limbs). Proximal and distal POPA's in dorsi-/plantar-flexion, in prone and erect positions, were imaged at rest and flexion. Peak systolic velocities (cm/s) and vessel diameter (antero-posterior, cm) was measured. RESULTS: Distal vessel occlusion was noted across all three groups whilst prone during plantar-flexion (62.7%). POPA occlusion was only noted in the proximal vessel within the patient group (15.8%). When prone, 50% of control (n = 40 limbs), 70% of athletes (n = 40 limbs), and 65% of patients (n = 40 limbs) had distal POPA occlusion in plantar-flexion. When prone, recreational athletes (5%), and patients (12.5%) had distal POPA compression under dorsi-flexion. POPA occlusions with the patient in erect position were only noted in the symptomatic patient group under both dorsi-flexion (15.8%) and plantar-flexion (23.7%). CONCLUSION: Compression of the POPA on ultrasound should not be the sole diagnostic criteria for PAES. POPA compression exists in asymptomatic individuals, primarily under prone plantar-flexion. To reduce false positives, ultrasound-based protocols should focus on scanning patients in the erect position only to diagnose PAES, rather than asymptomatic POPA compression. A distinction should be made between the two.

Documented Penicillin Allergies on Antibiotic Selection at Pediatric Emergency Department Visits.

BACKGROUND: Penicillin or amoxicillin are the recommended treatments for the most common pediatric bacterial illnesses. Allergies to penicillin are commonly reported among children but rarely true. We evaluated the impact of reported penicillin allergies on broad-spectrum antibiotic use overall and for the treatment of common respiratory infections among treat-and-release pediatric emergency department (ED) visits. METHODS: Retrospective cohort study of pediatric patients receiving antibiotics during a treat-and-release visit at a large, pediatric ED in the northeast from 2014 to 2016. Study exposure was a reported allergy to penicillin in the electronic medical record. Study outcomes were the selection of broad-spectrum antibiotics and alternative (second-line) antibiotic therapy for the treatment of acute otitis media (AOM) and group A streptococcus (GAS) pharyngitis. We used unadjusted and adjusted generalized estimating equation models to analyze the impact of reported penicillin allergies on the selection of broad-spectrum antibiotics. We used unadjusted and adjusted logistic regression models to determine the probability of children with a documented penicillin allergy receiving alternative antibiotic treatments for AOM and GAS. RESULTS: Among 12,987 pediatric patients, 810 (6.2%) had a documented penicillin allergy. Penicillin allergies increased the odds of children receiving a broad spectrum versus narrow spectrum antibiotic (adjusted odds ratio, 13.55; 95% confidence interval (CI), 11.34-16.18). In our adjusted logistic regression model, the probability of children with a documented penicillin allergy receiving alternative antibiotic treatment for AOM was 0.97 (95% CI, 0.94-0.99) and for GAS was 0.97 (95% CI, 0.92-0.99). CONCLUSIONS: Antibiotic stewardship efforts in pediatric EDs may consider the delabeling of penicillin allergies particularly among children receiving antibiotics for an acute respiratory infection as a target for intervention.

Development and Implementation of a Pediatric Nursing Emergency Behavioral Health Assessment Tool.

INTRODUCTION: The national pediatric mental and behavioral health crisis dramatically increased emergency department mental and behavioral health visits and changed emergency nursing practice. Acuity assessment determines patient severity level and supports appropriate resources and interventions. There are no established nursing tools that assess pediatric mental or behavioral health acuity in the emergency department setting. Our goal was to develop and implement the novel pediatric emergency nurse Emergency Behavioral Health Acuity Assessment Tool. METHODS: This quality-improvement project used the plan, do, study, act model to design/refine the Emergency Behavioral Health Acuity Assessment Tool and a non-experimental descriptive design to assess outcomes. The setting was a 47-bed urban level 1 pediatric trauma center with more than 60,000 annual visits. The team designed the tool using published evidence, emergency nurse feedback, and expert opinion. The tool objectively captured patient acuity and suggested acuity-specific nursing interventions. Project outcomes included acuity, length-of-stay, restraint use, and patient/staff injuries. Analyses included descriptive statistics and correlations. RESULTS: With over 3000 annual mental/behavioral-related visits, the emergency department had an average daily census of 23 mental and behavioral health patients. Implementation occurred in August 2021. The Emergency Behavioral Health Acuity Assessment Tool dashboard provided the number of patients, patient location, and acuity. Length-of-stay did not change; however, patient restraint use and patient/staff injuries declined. Number of restraints positively correlated with moderate acuity levels (r = 0.472, P = 0.036). DISCUSSION: For emergency nurses, the Emergency Behavioral Health Acuity Assessment Tool provided an objective measure of patient acuity. Targeted interventions can improve the care of this population.

Editor's Choice - Meta-Analysis of Compliance with Endovascular Aneurysm Repair Surveillance: The EVAR Surveillance Paradox.

OBJECTIVE: To compare the survival of patients who attended surveillance after endovascular aneurysm repair (EVAR) with those who were non-compliant. DATA SOURCES: MEDLINE and Embase were searched using the Ovid interface. REVIEW METHODS: A systematic review was conducted complying with the PRISMA guidelines. Eligible studies compared survival in EVAR surveillance compliant patients with non-compliant patients. Non-compliance was defined as failure to attend at least one post-EVAR follow up. The risk of bias was assessed with the Newcastle-Ottawa scale, and the certainty of evidence using the GRADE framework. Primary outcomes were survival and aneurysm related death. Effect measures were the hazard ratio (HR) or odds ratio (OR) and 95% confidence interval (CI) calculated using the inverse variance or Mantel-Haenszel statistical method and random effects models. RESULTS: Thirteen cohort studies with a total of 22 762 patients were included. Eight studies were deemed high risk of bias. The pooled proportion of patients who were non-compliant with EVAR surveillance was 43% (95% CI 36 - 51). No statistically significant difference was found in the hazard of all cause mortality (HR 1.04, 95% CI 0.61 - 1.77), aneurysm related mortality (HR 1.80, 95% CI 0.85-3.80), or secondary intervention (HR 0.66, 95% CI 0.31 - 1.41) between patients who had incomplete and complete follow up after EVAR. The odds of aneurysm rupture were lower in non-compliant patients (OR 0.63, 95% CI 0.39 - 1.01). The certainty of evidence was very low for all outcomes. Subgroup analysis for patients who had no surveillance vs. those with complete surveillance showed no significant difference in all cause mortality (HR 1.10, 95% CI 0.43 - 2.80). CONCLUSION: Patients who were non-compliant with EVAR surveillance had similar survival to those who were compliant. These findings question the value of intense surveillance in all patients post-EVAR and highlight the need for further research on individualised or risk adjusted surveillance.

The Impact of Family Functioning on Help-Seeking Behavior and Symptom Severity in Obsessive-Compulsive Disorder.

ABSTRACT: Poor family functioning is associated with higher symptom severity in pediatric obsessive-compulsive disorder (OCD) and delayed help-seeking behavior in other forms of psychopathology. However, little is known about the impact of family functioning on help-seeking behavior and symptom severity in adults with OCD. The present study investigated the association between family functioning and both treatment delay and symptom severity in adults with obsessive-compulsive symptoms. Participants were 194 adults who self-identified as having OCD and completed an internet survey, including measures assessing family functioning, obsessive-compulsive symptom severity, help-seeking behavior, and depression symptom severity. Poorer family functioning was associated with higher obsessive-compulsive and depression symptom severity, after controlling for significant demographic variables. With respect to domains of family functioning, poorer general functioning, problem solving, communication skills, role functioning, affective involvement, and affective responsiveness were associated with higher obsessive-compulsive and depression symptom severity, after controlling for demographics. Poorer problem solving and communication were not significantly associated with treatment delay after controlling for demographics. Findings highlight the need for family intervention within the treatment framework for adult OCD and suggest targets ( e.g. , communication) to be addressed.

Charging and Charged Species in Quantum Dot Light-Emitting Diodes.

Despite recent rapid advances in improving quantum dot light-emitting diodes, many fundamental aspects of the device operating mechanism remain unresolved. Through transient electroluminescence and time-resolved photoluminescence measurements, the effects of offset voltage on charging and charge transport are examined. First, capacitive charging occurs with a time constant of ∼500 ns, followed by electron transport through quantum dots with a mobility of ∼10-5 cm2 V-1 s-1. Hole injection then initiates an electroluminescence rise that is independent of offset voltage. The photoluminescence lifetime is also unaffected by the offset voltage, indicating no injection of charges into the quantum dots or on their surfaces prior to the voltage pulse. A slower equilibration to steady-state electroluminescence is dependent on the offset voltage, indicative of another charging process. Elemental mapping shows that ZnO deposition from solution can lead to the diffusion of charged species into the quantum dot layer, which may cause the slower process.

Nonreciprocity in Photon Pair Correlations of Classically Reciprocal Systems.

Nonreciprocal optical systems have found many applications altering the linear transmission of light as a function of its propagation direction. Here, we consider a new class of nonreciprocity which appears in photon pair correlations and not in linear transmission. We experimentally demonstrate and theoretically verify this nonreciprocity in the second-order coherence functions of photon pairs produced by spontaneous four-wave mixing in a silicon microdisk. Reversal of the pump propagation direction can result in substantial extinction of the coherence functions without altering pump transmission.

Aneurysm Geometry Analyzed by the Novel Three-Dimensional Tomographic Ultrasound Relates to Abdominal Aortic Aneurysm Growth.

BACKGROUND: Abdominal aortic aneurysms (AAAs) are increasingly screen-detected and many small aneurysms enter surveillance. Computed tomography identifies characteristics that can predict subsequent AAA growth but ionizing radiation and nephrotoxic contrast disadvantage its use in surveillance. We investigated whether duplex and 3-dimensional tomographic ultrasound identified features associated with AAA growth in patients on AAA surveillance. METHODS: Duplex and three-dimensional tomographic ultrasound imaging was performed independently by 2 vascular scientists in 128 AAA surveillance patients who all had AAA growth measured over at least 2 years. Diameter, cross-sectional area, length, volume, wall thickness/volume, and intraluminal thrombus were measured. Pulsatility using maximum systolic and minimum diastolic diameters corrected for diameter and distensibility (consisting of strain and stiffness) were also calculated. RESULTS: AAA growth rate correlated with AAA diameter (r 0.43), volume (r 0.46), and cross-sectional area (r 0.42) (P < 0.01). Measuring wall thickness was inaccurate, but wall volume (corrected for AAA volume) inversely related to growth rate (r -0.43, P < 0.01). On a multivariate analysis, diameter and wall volume (r2adjusted 0.22, P < 0.01) improved prediction of growth rate compared with diameter alone (r2adjusted 0.18, P < 0.01). Intraluminal thrombus volume, strain distensibility, and elastic distensibility were not significantly associated with AAA growth. CONCLUSIONS: AAA growth most strongly related to AAA volume and inversely to wall volume. AAA volume and wall volume may prove useful in the prediction of AAA growth rates.

Evaluating Potential Autologous Bypass Grafts with Tomographic Three-Dimensional Ultrasound Compared with Standard Color Duplex.

BACKGROUND: Vein mapping using duplex ultrasound (DUS) is a routine in selecting optimal autologous bypass grafts (aBG) but is time consuming and operator-dependent. Tomographic three-dimensional (3D) ultrasound (tUS), using free-hand electromagnetic tracking, allows cardiac and vascular surgeons to view 3D images of the entire length of the potential bypass graft. This study compares tUS with DUS in the evaluation of potential autologous grafts for coronary and lower limb bypass. METHODS: Both DUS and tUS imaging of 434 potential autologous grafts (364 long, 22 short saphenous veins, and 48 radial artery) immediately before bypass surgery were compared. The time in minutes to evaluate each aBG was recorded. Surgeons scored the quality of the aBG at operation. A score of 5 was in complete agreement with preoperative imaging with scores of 4 considered "good". RESULTS: Most operating surgeons (113, 57%) preferred interpreting the tUS images and felt that this technology could replace DUS completely. The choice of aBG would have been changed as a result of tUS images in 64 (32%) cases. DUS imaging took a mean (+/-sd) of 08:26 ± 04:44 minutes compared with only 01:00 ± 00:25 minutes for tUS (P < 0.001). However, processing the tUS images, which is currently done manually by the vascular scientist, took significantly longer at 19:31 ± 12:41 minutes compared with 09:03 ± 09:12 minutes for reporting DUS (P < 0.001). CONCLUSIONS: Surgeons preferred to see tUS images of the potential aBG themselves rather than relying on DUS reports. tUS images were significantly quicker than DUS to acquire but needed more processing time.

Deep Vein Thrombosis is Common After Cardiac Ablation and Pre-Procedural D-Dimer Could Predict Risk.

PURPOSE: Cardiac catheter ablations are an established treatment for supraventricular tachycardia (SVT) involving prolonged cannulation of the common femoral vein with multiple catheters. This study aimed to identify the risk of deep vein thrombosis (DVT) by studying the frequency of this complication after catheter ablation. METHODS: This was a prospective multi-centre cohort study of patients undergoing cardiac ablation for atrioventricular nodal re-entry tachycardia or right-sided accessory atrioventricular connection. Those taking anticoagulation or antiplatelet therapy prior to the procedure were excluded. Following the procedure, bilateral venous duplex ultrasonography from the popliteal vein to the inferior vena cava for DVT was undertaken at 24 hours and between 10 to 14 days. RESULTS: Eighty (80) patients (mean age 47.6 yrs [SD 13.4] with 67% female) underwent cardiac ablation (median duration 70 mins). Seven (7) patients developed acute DVT in either the femoral or external iliac vein of the intervention leg, giving a frequency of 8.8% (95% CI 3.6-17.2%). No thrombus was seen in the contralateral leg (p=0.023). An elevated D-dimer prior to the procedure was significantly more frequent in patients developing DVT (42.9% vs 4.1%, p=0.0081; OR 17.0). No other patient or procedural characteristics significantly influenced the risk of DVT. CONCLUSION: In patients without peri-procedural anticoagulation catheter ablation precipitated DVT in the catheterised femoral or iliac veins in 8.8% of patients. Peri-procedure prophylactic anticoagulation may be considered for all patients undergoing catheter ablation for SVT. CLINICAL TRIAL REGISTRATION: https://clinicaltrials.gov/ct2/show/NCT03877770.

Comparison Between Below Knee Contrast Enhanced Tomographic 3D Ultrasound and CT, MR or Catheter Angiography for Peripheral Artery Imaging.

OBJECTIVE: Clear imaging of below knee and foot arteries is essential to plan distal reconstructions. Contrast enhanced tomographic 3D ultrasound (CEtUS) is novel and entirely safe with no exposure to ionising radiation or nephrotoxic contrast. In the present study, inter- and intra-observer agreement of CEtUS was calculated, and compared with below knee angiography. METHODS: In the same week as computed tomography, magnetic resonance or catheter angiography, CEtUS was performed using intravenous 1.2 mL bolus injections of Sonovue with a maximum of 5 mL administered per patient. CEtUS was reported by a vascular scientist blinded to the angiograms reported by a consultant radiologist. Images were compared using a modified Society of Vascular Surgery (SVS) runoff score. RESULTS: Of the 181 patients recruited with peripheral arterial disease, 20 were excluded from analysis as they withdrew consent, could not be cannulated, or their images were non-diagnostic. In the remaining 161 patients, there were 175 comparative patient images split into two groups: 81 had calf imaging and 94 had pedal imaging representing 405 and 198 imaged arteries, respectively. Weighted quadratic kappa/ICC values for intra- and inter-observer agreement were excellent (κ/ICC = 0.83 to 0.95) and had narrow confidence intervals in both groups. When comparing angiography and CEtUS, weighted quadratic κ/ICC agreement was moderate with acceptable confidence intervals in both groups (Calf κ/ICC = 0.54; Pedal κ/ICC = 0.53). Agreement decreased from popliteal to pedal vessels as diameter decreased. Agreement between CEtUS and digital subtraction angiography was best, and computed tomography angiography the weakest. CONCLUSION: CEtUS is a novel imaging modality with strong observer agreement that achieves clear peripheral and foot images without ionising radiation exposure or nephrotoxic X-ray contrast media. CEtUS enhances visualisation of runoff vessels, which may play a role in planning of limb salvage or targeted assessment.

Arteriovenous Fistula Surveillance Using Tomographic 3D Ultrasound.

OBJECTIVE: A well functioning arteriovenous fistula (AVF) is essential for haemodialysis. Despite regular duplex ultrasound (DUS) a significant number of AVFs fail. Tomographic 3D ultrasound (tUS) creates a 3D image of the AVF that can be interpreted by the clinician. DUS, tUS, and fistulograms were compared for the identification and measurement of flow limiting stenosis. METHODS: Patients with AVF dysfunction on routine Transonic surveillance, defined as (1) > 15% reduction in flow on two consecutive occasions, (2) > 30% reduction in flow on one occasion, (3) flow of < 600 mL/sec, (4) presence of recirculation, underwent DUS. AVF tUS imaging was performed prior to fistulography. All fistulograms were reported by the same consultant radiologist and tUS images by the same vascular scientist blinded to the fistulogram results. Maximum diameter reduction in all stenoses were measured using all three imaging techniques. RESULTS: In 97 patients with 101 stenoses, the mean (± standard deviation [SD]) severity of stenosis was 63.0 ± 13.9%, 65.0 ± 11.6%, and 64.8 ± 11.7% for the fistulograms, DUS, and tUS respectively. The mean (± SD) time between ultrasound and fistulography imaging was 15.0 ± 14.5 days. Assuming the fistulogram as the "gold standard", Bland-Altman agreement for DUS was -1.9 ± 15.5% (limit of agreement [LOA] -32.2 - 28.4) compared with -1.7 ± 15.4% (LOA -31.9 - 28.4) for tUS. Median (± interquartile range) time to complete the investigation was 09:00 ± 03:19 minutes for DUS and 03:13 ± 01:56 minutes for tUS (p < .001). CONCLUSION: DUS and tUS were equally accurate at detecting AVF complications but tUS investigation requires less skill and was significantly quicker than DUS.

Endovascular Aneurysm Repair Assisted by CO2 Digital Subtraction Angiography and Intraoperative Contrast-Enhanced Ultrasonography: Single-Center Experience.

BACKGROUND: Allergy to iodinated contrast (IC) agent and advanced chronic kidney disease are major limitations to endovascular repair (EVAR) of abdominal aortic aneurysms (AAAs). We describe our experience combining CO2-assisted EVAR with intraoperative contrast-enhanced ultrasound (CEUS) in an attempt to avoid contrast-induced allergy or nephropathy. METHODS: Observational cohort study using prospectively acquired data on patients undergoing CO2-assisted EVAR in single institution. EVAR planning was performed using computed tomographic angiography or magnetic resonance aortography in patients contraindicated for IC. Patients were considered if their estimated glomerular filtration rate was <40 mL/min and anatomically suitable for conventional infrarenal EVAR. Outcomes of interest included technical success rate and reintervention rates, total radiation dose, length of hospital stay, and graft kinking or migration. RESULTS: Fifteen patients (10 male) were treated across a 5-year period. Technical success was achieved in all cases. Completely IC-free EVAR was performed in 9 cases, whereas the remaining 6 required IC administration for adjunct procedures. CO2 completion angiography detected all type I endoleaks (2 Ia and 1 Ib) but was less sensitive to type II. Intraoperative CEUS confirmed all type I and 2 cases of type II endoleaks. Median hospital stay was 4 days. No significant deterioration in renal function was seen postoperatively. CONCLUSIONS: In patients with abdominal aortic aneurysms and with contraindication for IC, a combined approach of using CO2 digital subtraction angiography and CEUS can be used safely and efficiently to minimize or obviate the need for IC agents with satisfactory mid-term results.

Violence prevention emergency tool (VPET) screening of youth in the pediatric ED.

Background Violence is an increasingly common and significant problem for youth worldwide. Youth who rely on treatment at urban EDs are more likely to die as the result of violence than any other disease/condition for which they seek care. The first step in helping youth that are at risk, is identifying them. We developed a 7-item screening tool called VPET. The purpose of this study is to validate the VPET screening tool in identifying high-risk youth. Methods and findings We prospectively enrolled a convenience sample of children during the index ED visit who were called 3 months and 6 months after this visit. 269 youth (33%) completed 3-month follow up (44.2% male); 240 youth (29.4%) completed 6-month follow up (45% male); 84.0% reported some level of violence exposure after 3-months and 84.2% (n = 240) reported some level of violence exposure after 6-months. Predictive validity was assessed by Spearman's correlation between VPET score and follow-up score at 3-months and 6-months post-enrollment; logistic regression to calculate odds ratios between positive VPET item responses and positive follow-up score; ROC curve analysis. VPET score had internal consistency, as tested by Cronbach's alpha (α = 0.642). Children who were male, non-white, and had been hurt at home or school reported the highest VPET scores. Conclusion VPET has sufficiently strong psychometric function and performs well as a screening tool to predict future violence exposure for youth ages 8-17. Five questions on the VPET screening tool are independently predictive of violence reported at 6 months and four questions at 3 months.

Prevalence of Cyberbullying in Patients Presenting to the Pediatric Emergency Department.

OBJECTIVES: Mental health (MH) complaints are increasingly responsible for visits to pediatric emergency departments (PEDs). Bullying is associated with MH problems. Most adolescents use social media and many experience problems with cyberbullying (CB). This study determines prevalence of CB in MH and non-MH adolescents in a PED, describes technology use in these groups, and measures influence of CB on presentation to the PED and on thoughts/acts of self-harm. METHODS: A prospective survey was administered to a convenience sample of 149 patients aged 11 to 17 years in a PED. Data were analyzed using descriptive and comparative statistical methods. RESULTS: Cyberbullying was significantly more common in MH than in the non-MH patients (17% vs 3%, P = 0.007). More MH patients reported that bullying led to the current PED visit than that in the non-MH group (25% vs 10%, P = 0.02), and they were significantly more likely to report that CB led to self-harm (22% vs 4%, P = 0.003). Mental health participants who spent more than 3 hours on the Internet report higher levels of bullying than non-MH patients (38% vs 6%, P < 0.001). CONCLUSIONS: Prevalence of bullying in MH patients presenting to a PED is significantly greater than controls, and CB caused more MH patients to have acts or thoughts of self-harm. Bullying is a risk factor for self-harm and suicide in patients with MH problems. Future studies should evaluate CB as part of suicide screening tools for emergency MH patients.

European Society for Vascular Surgery (ESVS) Certification of Theoretical and Practical Competences in Basic Vascular Ultrasound: Validity Investigation of the Assessment Tools.

OBJECTIVE: The aim of this study was to gather validity evidence for the Assessment of basic Vascular Ultrasound Expertise (AVAUSE) tool, and to establish a pass/fail score for each component, to support decisions for certification. METHODS: A cross sectional validation study performed during the European Society for Vascular Surgery's annual meeting. Validity evidence was sought for the theoretical test and two practical tests based on Messick's framework. The participants were vascular surgeons, vascular surgical trainees, sonographers, and nurses with varying experience levels. Five vascular ultrasound experts developed the theoretical and two practical test components of the AVAUSE tool for each test component. Two stations were set up for carotid examinations and two for superficial venous incompetence (SVI) examinations. Eight raters were assigned in pairs to each station. Three methods were used to set pass/fail scores: contrasting groups' method; rater consensus; and extended Angoff. RESULTS: Nineteen participants were enrolled. Acceptable internal consistency reliability (Cronbach's alpha) for the AVAUSE theoretical (0.93), carotid (0.84), and SVI (0.65) practical test were shown. In the carotid examination, inter-rater reliability (IRR) for the two rater pairs was good: 0.68 and 0.78, respectively. The carotid scores correlated significantly with years of experience (Pearson's r = 0.56, p = .013) but not with number of examinations in the last five years. For SVI, IRR was excellent at 0.81 and 0.87. SVI performance scores did not correlate with years of experience and number of examinations. The pass/fail score set by the contrasting groups' method was 29 points out of 50. The rater set pass/fail scores were 3.0 points for both carotid and SVI examinations and were used to determine successful participants. Ten of 19 participants passed the tests and were certified. CONCLUSION: Validity evidence was sought and established for the AVAUSE comprehensive tool, including pass/fail standards. AVAUSE can be used to assess competences in basic vascular ultrasound, allowing operators to progress towards independent practice.

Silicon carbide double-microdisk resonator.

We demonstrate the first silicon carbide (SiC) double-microdisk resonator (DMR). The device has a compact footprint with a radius of 24 µm and operates in the ITU high frequency range (3-30 MHz). We develop a multi-layer nanofabrication recipe that yields high optical quality (Q∼105) for the SiC DMR. Because of its strong optomechanical interaction, we observe the thermal-Brownian motions of mechanical modes in a SiC DMR directly at room temperature for the first time, to the best of our knowledge. The observed mechanical modes include fundamental/second-order common modes and fundamental differential (D1) modes. The D1 modes have high mechanical qualities >3800 at around 18.4 MHz tested in vacuum. We further show that optomechanical interactions, including linear and nonlinear optomechanical spring effects, can be observed in a SiC DMR at sub-milliwatt optical power. The SiC DMR has great potential for low-power optomechanical sensing applications in harsh environments.

Natural product derivative Gossypolone inhibits Musashi family of RNA-binding proteins.

BACKGROUND: The Musashi (MSI) family of RNA-binding proteins is best known for the role in post-transcriptional regulation of target mRNAs. Elevated MSI1 levels in a variety of human cancer are associated with up-regulation of Notch/Wnt signaling. MSI1 binds to and negatively regulates translation of Numb and APC (adenomatous polyposis coli), negative regulators of Notch and Wnt signaling respectively. METHODS: Previously, we have shown that the natural product (-)-gossypol as the first known small molecule inhibitor of MSI1 that down-regulates Notch/Wnt signaling and inhibits tumor xenograft growth in vivo. Using a fluorescence polarization (FP) competition assay, we identified gossypolone (Gn) with a > 20-fold increase in Ki value compared to (-)-gossypol. We validated Gn binding to MSI1 using surface plasmon resonance, nuclear magnetic resonance, and cellular thermal shift assay, and tested the effects of Gn on colon cancer cells and colon cancer DLD-1 xenografts in nude mice. RESULTS: In colon cancer cells, Gn reduced Notch/Wnt signaling and induced apoptosis. Compared to (-)-gossypol, the same concentration of Gn is less active in all the cell assays tested. To increase Gn bioavailability, we used PEGylated liposomes in our in vivo studies. Gn-lip via tail vein injection inhibited the growth of human colon cancer DLD-1 xenografts in nude mice, as compared to the untreated control (P < 0.01, n = 10). CONCLUSION: Our data suggest that PEGylation improved the bioavailability of Gn as well as achieved tumor-targeted delivery and controlled release of Gn, which enhanced its overall biocompatibility and drug efficacy in vivo. This provides proof of concept for the development of Gn-lip as a molecular therapy for colon cancer with MSI1/MSI2 overexpression.