Citations

ABSTRACT The last decade has seen a sharp increase in the number of scientific publications describing physiological and pathological functions of extracellular vesicles (EVs), a collective term covering various subtypes of cell‐released, membranous structures, called exosomes, microvesicles, microparticles, ectosomes, oncosomes, apoptotic bodies, and many other names. However, specific issues arise when working with these entities, whose size and amount often make them difficult to obtain as relatively pure preparations, and to characterize properly. The International Society for Extracellular Vesicles (ISEV) proposed Minimal Information for Studies of Extracellular Vesicles (“MISEV”) guidelines for the field in 2014. We now update these “MISEV2014” guidelines based on evolution of the collective knowledge in the last four years. An important point to consider is that ascribing a specific function to EVs in general, or to subtypes of EVs, requires reporting of specific information beyond mere description of function in a crude, potentially contaminated, and heterogeneous preparation. For example, claims that exosomes are endowed with exquisite and specific activities remain difficult to support experimentally, given our still limited knowledge of their specific molecular machineries of biogenesis and release, as compared with other biophysically similar EVs. The MISEV2018 guidelines include tables and outlines of suggested protocols and steps to follow to document specific EV‐associated functional activities. Finally, a checklist is provided with summaries of key points.

Abstract Background Transcatheter Aortic Valve Implantation (TAVI) is commonly used to deploy new bioprosthetic valves inside degenerated surgically implanted aortic valves in high risk patients. The three scoring systems used to assess risk of postprocedural mortality are: Logistic EuroSCORE (LES), EuroSCORE II (ES II), and Society of Thoracic Surgeons (STS). Objective The purpose of this study is to analyze the accuracy of LES, ES II, and STS in estimating all‐cause mortality after transcatheter aortic valve‐in‐valve (ViV) implantations, which was not assessed before. Methods Using the Valve‐in‐Valve International Data (VIVID) registry, a total of 1,550 patients from 110 centers were included. The study compared the observed 30‐day overall mortality vs. the respective predicted mortalities calculated by risk scores. The accuracy of prediction models was assessed based on calibration and discrimination. Results Observed mortality at 30 days was 5.3%, while average expected mortalities by LES, ES II and STS were 29.49 (± 17.2), 14.59 (± 8.6), and 9.61 (± 8.51), respectively. All three risk scores overestimated 30‐day mortality with ratios of 0.176 (95% CI 0.138–0.214), 0.342 (95% CI 0.264–0.419), and 0.536 (95% CI 0.421–0.651), respectively. 30‐day mortality ROC curves demonstrated that ES II had the largest AUC at 0.722, followed by STS at 0.704, and LES at 0.698. Conclusions All three scores overestimated mortality at 30 days with ES II showing the highest predictability compared to LES and STS; and therefore, should be recommended for ViV procedures. There is a need for a dedicated scoring system for patients undergoing ViV interventions.

BACKGROUNDDelirium is associated with poor outcomes in adults but is less extensively studied in children.OBJECTIVESTo describe a quality improvement initiative to implement delirium assessment in a pediatric intensive care unit and to identify barriers to delirium screening completion.METHODSA survey identified perceived barriers to delirium assessment. Failure modes and effects analysis characterized factors likely to impede assessment. A randomized case-control study evaluated factors affecting assessment by comparing patients always assessed with patients never assessed.RESULTSDelirium assessment was completed in 57% of opportunities over 1 year, with 2% positive screen results. Education improved screening completion by 20%. Barriers to assessment identified by survey (n = 25) included remembering to complete assessments, documentation outside workflow, and “busy patient.” Factors with high risk prediction numbers were lack of time and paper charting. Patients always assessed had more severe illness (median Pediatric Index of Mortality 2 score, 0.90 vs 0.36; P < .001), more developmental disabilities (moderate to severe pediatric cerebral performance category score, 54% vs 32%; P = .007), and admission during lower pediatric intensive care unit census (median [interquartile range], 10 [9–12] vs 12 [10–13]; P < .001) than did those never assessed (each group, n = 80). Patients receiving mechanical ventilation were less likely to be assessed (41.0% vs 51.2%, P < .001).CONCLUSIONSSuccessful implementation of pediatric delirium screening may be associated with early use of quality improvement tools to identify assessment barriers, comprehensive education, monitoring system with feedback, multidisciplinary team involvement, and incorporation into nursing workflow models.

An automated method for specific factor assays has been developed using a novel thrombin-specific chromogenic substrate (developed by A. Aiyappa, Ph. D., Abbott Labs). For factors VIII, IX, XI and XII, the test system includes an ellagic acid activator and brain phospholipid in a calcium containing tris buffer pH 7.4. These are mixed with a plasma sample consisting of a mixture of specific factor deficient substrate and test plasma for 5 minutes and then the chromogenic substrate is added. After another 5 minutes the increase in optical density ΔOD is recorded. Normal plasma serially diluted in specific factor deficient substrate is used to construct a standard graph and test plasma results are interpolated from this.Fifty-four comparative assays have been done for factors VIII and IX and correlated with the results obtained from conventional clotting assays. For factor VIII the correlation coefficient (r)=0.935 (N=35) and for factor IX r=0.941 (N=19). While insufficient data exists to date for factors XI and XII, these assays appear to be comparable to the VIII and IX results.The assays for factors V, VII and X use a simplified system in that the chromogenic substrate and phospholipid are added together. The ΔOD is again recorded after 5 minutes. Test plasma results are interpolated from a standard graph constructed using serially diluted normal plasma as before. To date only the factor V assay has enough data to do a correlation with the clotting assays and r=0.953 (N=13) which is similar to the r value for the VIII and IX assays.Because of the widespread availability of the automated analyzer used in the assay and the standardization of end point determination it provides, specific factor assays might be made more widely available outside specialized coagulation centers.

The variability of normal ranges in different laboratories and the occurrence of occasional elevated values of β-TG and PF-4 in normal subjects are well established. We examined the influence of factors such as age, sex, smoking, exercise, oral contraceptives and day-to-day variation in 148 healthy subjects. The β-TG and PF-4 assays were performed by commercial RIA’s modified by utilizing an EDTA- PGE1 -theophylline mixture as anticoagulant.The statistical method used to compare our groups was a student t-test after log transformation of the data. Our baseline control group (N=63) were non smokers and not taking oral contraceptives (O/C) or any medications. There was no difference between sexes or a significant change with increasing age, although the mean β-TG and PF-4 does increase in cohosts of 20 years. [<30 years (21.65±8.35)(SD), 30-50 years (24.32±10.94) >50 years (27.88±14.3)-β-TG data].Women on O/C were significantly different from those not on O/C for β-TG [35.06±22.45 (O/C) and 23.67±9.38 (N)] but not for PF-4 values [3.79±1.77 (O/C) and 3.91±1.63 (N)].Strenuous exercise was the parameter that influenced both β-TG and PF-4 significantly, showing an elevated value after exercise for both β-TG [81.9±31.4 v 26.73±10.91] and PF-4 [7.08±1.71 v 3.73±1.91].Day-to-day variations in β-TG and PF-4 were examined in 10 subjects for 7-10 days. The coefficient of variation (CV) amongst these subjects was 21-51%. In athletes day-today variation was the same unless a change in pattern of exercise occurred [CV-49-132%].Our results confirm that parameters such as above do influence normal values and should be taken into consideration in establishing a normal range.It also indicates the β-TG is a more sensitive parameter for delineating differences in physiological parameters in normal subjects than PF-4, and this may be applicable to clinical studies.

Medication reconciliation (MedRec) is a mission-critical process which can serve to reduce adverse drug events (ADEs) in surgical settings. However, providing quality care is limited by current health information technology (IT), which is often inefficient and unintuitive due to poor usability, resulting in high cognitive burden. We have been characterizing EHR mediated workflow in the Mayo Clinic enterprise prior to a system-wide electronic health records (EHR) conversion in order to harmonize workflows. We compared and evaluated MedRec processes in pre-operative nursing assessments across two different EHRs in place in different locales at baseline. The interfaces differed both in their modes of interaction and cognitive support. Analyses surfaced interface elements that were unintuitive and inefficient, creating unnecessary complexities in clinicians’ interactive behavior. Keystroke level models (KLM), a modeling tool for predicting task completion time, showed that to access medication lists required a different series of operations across the two systems. Different designs can differentially mediate task performance, which can aid in the mitigation of errors for complex cognitive tasks. Identification of barriers in EHR-mediated workflow and barriers to interface usability could lead to system redesigns that minimize cognitive load while improving patient safety and efficiency.

ObjectiveTo examine the association between macrophage migration inhibitory factor (MIF) promoter polymorphisms and granulomatosis with polyangiitis (GPA) in human subjects, and to assess the role of MIF in a murine model of granulomatous vasculitis.MethodsThe human study involved 1,077 patients with GPA and healthy controls whose serum was genotyped by capillary electrophoresis for the MIF −794 CATT5−8 promoter microsatellite (rs5844572). MIF promoter, CATT‐length–dependent gene expression in response to β‐glucan was assessed by gene reporter assays. In mouse studies, granulomatous disease was induced by injection of Candida albicans β‐glucan into wild‐type (WT) or Mif‐knockout (Mif‐KO) C57BL/6 mice and C57BL/6 mice transgenically overexpressing Mif in lung epithelium (Mif lung–Tg2.1). Mice were treated with a neutralizing anti‐MIF antibody and analyzed for the density of pulmonary granulomas, expression of inflammatory chemokines, and frequency of mortality.ResultsThe percentage of human subjects carrying >5 CATT repeats in each MIF allele (high genotypic MIF expressers) was 60.2% among patients with GPA and 53.9% among healthy controls (adjusted P = 0.049). In response to granulomatous stimulation, human MIF gene expression increased proportionally with CATT length. Mif lung–Tg2.1 mice exhibited more pulmonary granulomas than WT mice, which in turn showed more granulomas than Mif‐KO mice. A significantly higher percentage of Mif lung–Tg2.1 mice, compared to Mif‐KO or WT mice, died when injected with Candida albicans β‐glucan, and treatment of these mice with an anti‐MIF monoclonal antibody protected against a lethal outcome. Levels of MIF‐dependent neutrophil/macrophage chemokines were elevated in the bronchoalveolar lavage fluid or plasma of Mif lung–Tg2.1 mice.ConclusionPatients with GPA have an increased frequency of high MIF expression CATT alleles. Higher Mif expression increases the incidence of mortality and pulmonary granulomas in Mif lung–Tg2.1 mice, while anti‐MIF treatment protects these mice against death. Blockade of MIF in high genotypic MIF expressers may therefore offer a selective pharmacologic therapy for GPA.

Abstract Background Previous genome-wide association studies (GWAS) have identified 42 loci (P < 5 × 10−8) associated with risk of colorectal cancer (CRC). Expanded consortium efforts facilitating the discovery of additional susceptibility loci may capture unexplained familial risk. Methods We conducted a GWAS in European descent CRC cases and control subjects using a discovery–replication design, followed by examination of novel findings in a multiethnic sample (cumulative n = 163 315). In the discovery stage (36 948 case subjects/30 864 control subjects), we identified genetic variants with a minor allele frequency of 1% or greater associated with risk of CRC using logistic regression followed by a fixed-effects inverse variance weighted meta-analysis. All novel independent variants reaching genome-wide statistical significance (two-sided P < 5 × 10−8) were tested for replication in separate European ancestry samples (12 952 case subjects/48 383 control subjects). Next, we examined the generalizability of discovered variants in East Asians, African Americans, and Hispanics (12 085 case subjects/22 083 control subjects). Finally, we examined the contributions of novel risk variants to familial relative risk and examined the prediction capabilities of a polygenic risk score. All statistical tests were two-sided. Results The discovery GWAS identified 11 variants associated with CRC at P < 5 × 10−8, of which nine (at 4q22.2/5p15.33/5p13.1/6p21.31/6p12.1/10q11.23/12q24.21/16q24.1/20q13.13) independently replicated at a P value of less than .05. Multiethnic follow-up supported the generalizability of discovery findings. These results demonstrated a 14.7% increase in familial relative risk explained by common risk alleles from 10.3% (95% confidence interval [CI] = 7.9% to 13.7%; known variants) to 11.9% (95% CI = 9.2% to 15.5%; known and novel variants). A polygenic risk score identified 4.3% of the population at an odds ratio for developing CRC of at least 2.0. Conclusions This study provides insight into the architecture of common genetic variation contributing to CRC etiology and improves risk prediction for individualized screening.