Metabolomics Simultaneously Derives Benchmark Dose Estimates and Discovers Metabolic Biotransformations in a Rat Bioassay.

Benchmark dose (BMD) modeling estimates the dose of a chemical that causes a perturbation from baseline. Transcriptional BMDs have been shown to be relatively consistent with apical end point BMDs, opening the door to using molecular BMDs to derive human health-based guidance values for chemical exposure. Metabolomics measures the responses of small-molecule endogenous metabolites to chemical exposure, complementing transcriptomics by characterizing downstream molecular phenotypes that are more closely associated with apical end points. The aim of this study was to apply BMD modeling to in vivo metabolomics data, to compare metabolic BMDs to both transcriptional and apical end point BMDs. This builds upon our previous application of transcriptomics and BMD modeling to a 5-day rat study of triphenyl phosphate (TPhP), applying metabolomics to the same archived tissues. Specifically, liver from rats exposed to five doses of TPhP was investigated using liquid chromatography-mass spectrometry and 1H nuclear magnetic resonance spectroscopy-based metabolomics. Following the application of BMDExpress2 software, 2903 endogenous metabolic features yielded viable dose-response models, confirming a perturbation to the liver metabolome. Metabolic BMD estimates were similarly sensitive to transcriptional BMDs, and more sensitive than both clinical chemistry and apical end point BMDs. Pathway analysis of the multiomics data sets revealed a major effect of TPhP exposure on cholesterol (and downstream) pathways, consistent with clinical chemistry measurements. Additionally, the transcriptomics data indicated that TPhP activated xenobiotic metabolism pathways, which was confirmed by using the underexploited capability of metabolomics to detect xenobiotic-related compounds. Eleven biotransformation products of TPhP were discovered, and their levels were highly correlated with multiple xenobiotic metabolism genes. This work provides a case study showing how metabolomics and transcriptomics can estimate mechanistically anchored points-of-departure. Furthermore, the study demonstrates how metabolomics can also discover biotransformation products, which could be of value within a regulatory setting, for example, as an enhancement of OECD Test Guideline 417 (toxicokinetics).

Multi-omics bioactivity profile-based chemical grouping and read-across: a case study with Daphnia magna and azo dyes.

Grouping/read-across is widely used for predicting the toxicity of data-poor target substance(s) using data-rich source substance(s). While the chemical industry and the regulators recognise its benefits, registration dossiers are often rejected due to weak analogue/category justifications based largely on the structural similarity of source and target substances. Here we demonstrate how multi-omics measurements can improve confidence in grouping via a statistical assessment of the similarity of molecular effects. Six azo dyes provided a pool of potential source substances to predict long-term toxicity to aquatic invertebrates (Daphnia magna) for the dye Disperse Yellow 3 (DY3) as the target substance. First, we assessed the structural similarities of the dyes, generating a grouping hypothesis with DY3 and two Sudan dyes within one group. Daphnia magna were exposed acutely to equi-effective doses of all seven dyes (each at 3 doses and 3 time points), transcriptomics and metabolomics data were generated from 760 samples. Multi-omics bioactivity profile-based grouping uniquely revealed that Sudan 1 (S1) is the most suitable analogue for read-across to DY3. Mapping ToxPrint structural fingerprints of the dyes onto the bioactivity profile-based grouping indicated an aromatic alcohol moiety could be responsible for this bioactivity similarity. The long-term reproductive toxicity to aquatic invertebrates of DY3 was predicted from S1 (21-day NOEC, 40 µg/L). This prediction was confirmed experimentally by measuring the toxicity of DY3 in D. magna. While limitations of this 'omics approach are identified, the study illustrates an effective statistical approach for building chemical groups.

A Modified Delphi Consensus Approach to Define Entrustable Professional Activities for Neurocritical Care Advanced Practice Providers.

OBJECTIVES: To define consensus entrustable professional activities (EPAs) for neurocritical care (NCC) advanced practice providers (APPs), establish validity evidence for the EPAs, and evaluate factors that inform entrustment expectations of NCC APP supervisors. DESIGN: A three-round modified Delphi consensus process followed by application of the EQual rubric and assessment of generalizability by clinicians not affiliated with academic medical centers. SETTING: Electronic surveys. SUBJECTS: NCC APPs ( n = 18) and physicians ( n = 12) in the United States with experience in education scholarship or APP program leadership. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: The steering committee generated an initial list of 61 possible EPAs. The panel proposed 30 additional EPAs. A total of 47 unique nested EPAs were retained by consensus opinion. The steering committee defined six core EPAs addressing medical knowledge, procedural competencies, and communication proficiency which encompassed the nested EPAs. All core EPAs were retained and subsequently met the previously described cut score for quality and structure using the EQual rubric. Most clinicians who were not affiliated with academic medical centers rated each of the six core EPAs as very important or mandatory. Entrustment expectations did not vary by prespecified groups. CONCLUSIONS: Expert consensus was used to create EPAs for NCC APPs that reached a predefined quality standard and were important to most clinicians in different practice settings. We did not identify variables that significantly predicted entrustment expectations. These EPAs may aid in curricular design for an EPA-based assessment of new NCC APPs and may inform the development of EPAs for APPs in other critical care subspecialties.

Research considerations for prospective studies of patients with coma and disorders of consciousness.

Disorders of consciousness are neurological conditions characterized by impaired arousal and awareness of self and environment. Behavioural responses are absent or are present but fluctuate. Disorders of consciousness are commonly encountered as a consequence of both acute and chronic brain injuries, yet reliable epidemiological estimates would require inclusive, operational definitions of the concept, as well as wider knowledge dissemination among involved professionals. Whereas several manifestations have been described, including coma, vegetative state/unresponsive wakefulness syndrome and minimally conscious state, a comprehensive neurobiological definition for disorders of consciousness is still lacking. The scientific literature is primarily observational, and studies-specific aetiologies lead to disorders of consciousness. Despite advances in these disease-related forms, there remains uncertainty about whether disorders of consciousness are a disease-agnostic unitary entity with a common mechanism, prognosis or treatment response paradigm. Our knowledge of disorders of consciousness has also been hampered by heterogeneity of study designs, variables, and outcomes, leading to results that are not comparable for evidence synthesis. The different backgrounds of professionals caring for patients with disorders of consciousness and the different goals at different stages of care could partly explain this variability. The Prospective Studies working group of the Neurocritical Care Society Curing Coma Campaign was established to create a platform for observational studies and future clinical trials on disorders of consciousness and coma across the continuum of care. In this narrative review, the author panel presents limitations of prior observational clinical research and outlines practical considerations for future investigations. A narrative review format was selected to ensure that the full breadth of study design considerations could be addressed and to facilitate a future consensus-based statement (e.g. via a modified Delphi) and series of recommendations. The panel convened weekly online meetings from October 2021 to December 2022. Research considerations addressed the nosographic status of disorders of consciousness, case ascertainment and verification, selection of dependent variables, choice of covariates and measurement and analysis of outcomes and covariates, aiming to promote more homogeneous designs and practices in future observational studies. The goal of this review is to inform a broad community of professionals with different backgrounds and clinical interests to address the methodological challenges imposed by the transition of care from acute to chronic stages and to streamline data gathering for patients with disorders of consciousness. A coordinated effort will be a key to allow reliable observational data synthesis and epidemiological estimates and ultimately inform condition-modifying clinical trials.

Wear of lithium disilicate opposed by various ceramic materials.

OBJECTIVES: To compare volumetric wear of lithium disilicate against different ceramic (3 mol% yttria-stabilized (3Y) zirconia, 5 mol% yttria-stabilized (5Y) zirconia, lithium disilicate, porcelain and enamel antagonists). MATERIALS AND METHODS: Forty lithium disilicate (e.max CAD) specimens (n = 8/antagonist) were wet sanded to 1200grit SiC and mounted into a UAB wear device. Antagonist spheres (diameter = 4.75 mm) were made from polished 3Y zirconia, 5Y zirconia, lithium disilicate, porcelain and human enamel. A two-body wear test was performed with 20 N load and 1.5 mm slide for 400,000 cycles at 1 Hz. 33% glycerin was used as a lubricant. Wear facets were measured with optical profilometry. Wear scar areas of antagonists were measured with digital microscopy. Scanning electron microscopy was performed on wear facets and scars. Vicker's microhardness was measured of all antagonist materials. All data were compared with 1-way ANOVA and Tukey post-hoc analysis. RESULTS: Significant differences in lithium disilicate volumetric wear (mm3 ) occurred with various antagonist materials: 0.38 ± 0.01a (3Y zirconia), 0.33 ± 0.01b, (5Y zirconia), 0.16 ± 0.01c (lithium disilicate), 0.11 ± 0.03d, (enamel), and 0.07 ± 0.01e (porcelain). The lithium disilicate antagonist demonstrated a larger wear scar than other materials. Zirconia was the hardest material and enamel the least hard. CONCLUSIONS: Zirconia causes significant wear on lithium disilicate and lithium disilicate causes significant wear against itself. CLINICAL SIGNIFICANCE: When selecting a material to oppose an existing lithium disilicate crown, a porcelain or lithium disilicate surface would cause significantly less wear to the existing crown. If an existing zirconia crown exists opposed to a prepared tooth, lithium disilicate may not be an ideal material selection to restore the tooth.

Incidence and prevalence of coma in the UK and the USA.

The epidemiology of coma is unknown because case ascertainment with traditional methods is difficult. Here, we used crowdsourcing methodology to estimate the incidence and prevalence of coma in the UK and the USA. We recruited UK and US laypeople (aged ≥18 years) who were nationally representative (i.e. matched for age, gender and ethnicity according to census data) of the UK and the USA, respectively, utilizing a crowdsourcing platform. We provided a description of coma and asked survey participants if they-'right now' or 'within the last year'-had a family member in coma. These participants (UK n = 994, USA n = 977) provided data on 30 387 family members (UK n = 14 124, USA n = 16 263). We found more coma cases in the USA (n = 47) than in the UK (n = 20; P = 0.009). We identified one coma case in the UK (0.007%, 95% confidence interval 0.00-0.04%) on the day of the survey and 19 new coma cases (0.13%, 95% confidence interval 0.08-0.21%) within the preceding year, resulting in an annual incidence of 135/100 000 (95% confidence interval 81-210) and a point prevalence of 7 cases per 100 000 population (95% confidence interval 0.18-39.44) in the UK. We identified five cases in the USA (0.031%, 95% confidence interval 0.01-0.07%) on the day of the survey and 42 new cases (0.26%, 95% confidence interval 0.19-0.35%) within the preceding year, resulting in an annual incidence of 258/100 000 (95% confidence interval 186-349) and a point prevalence of 31 cases per 100 000 population (95% confidence interval 9.98-71.73) in the USA. The five most common causes were stroke, medically induced coma, COVID-19, traumatic brain injury and cardiac arrest. To summarize, for the first time, we report incidence and prevalence estimates for coma across diagnosis types and settings in the UK and the USA using crowdsourcing methods. Coma may be more prevalent in the USA than in the UK, which requires further investigation. These data are urgently needed to expand the public health perspective on coma and disorders of consciousness.

A Scoping Review of the Incidence, Predictors, and Outcomes of Delirium Among Critically Ill Stroke Patients.

ABSTRACT: BACKGROUND: Delirium is a common, often iatrogenically induced syndrome that may impede the physical, cognitive, and psychological recovery of critically ill adults. The effect delirium has on outcomes of intensive care unit patients having acute neurologic injury remains unclear because previous studies frequently exclude this vulnerable population. The aim of this scoping review was to describe the incidence, predictors, and outcomes of delirium among adults admitted to an intensive care unit experiencing an acute ischemic stroke, intracerebral hemorrhage, or aneurysmal subarachnoid hemorrhage. METHODS: PubMed, CINAHL, Web of Science, EMBASE, and Scopus were searched with the terms (1) stroke, (2) critical care, and (3) delirium. Inclusion criteria were original peer-reviewed research reporting the incidence, outcomes, or predictors of delirium after acute stroke among critically ill adults. Editorials, reviews, posters, conference proceedings, abstracts, and studies in which stroke was not the primary reason for admission were excluded. Title and abstract screening, full-text review, and data extraction were performed by 2 authors, with disagreements adjudicated by a third author. RESULTS: The initial search yielded 1051 results. Eighteen studies met eligibility criteria and were included in the review. Stroke type was not mutually exclusive and included persons given a diagnosis of acute ischemic stroke (11), intracerebral hemorrhage (12), aneurysmal subarachnoid hemorrhage (8), and other (1) strokes. Incidence of delirium among stroke patients ranged from 12% to 75%. Predictors of delirium included older age, preexisting dementia, higher severity of illness, and physical restraint use. Outcomes associated with delirium included higher mortality, longer length of stay, worse cognition and quality of life, and lower functional status. CONCLUSIONS: Current findings are limited by heterogenous populations, assessments, and measurement parameters. Detection and management of delirium among critically ill stroke patients requires an approach with specific considerations to the complexities of acute neurological injury and concomitant critical illness.

Nucleic Acid Substrate-Independent DNA Polymerization on the Exosome Membrane: A Mechanism Study and Application in Exosome Analysis.

As generally acknowledged, terminal deoxynucleotidyl transferase (TdT) can only elongate DNA substrates from their 3'-OH ends. Herein, for the first time, we report that TdT-catalyzed DNA polymerization can directly proceed on the exosome membrane without the mediation of any nucleic acids. We prove that both the glycosyl and phenolic hydroxyl groups on the membrane proteins can initiate the DNA polymerization. Accordingly, we have developed powerful strategies for high-sensitive exosome profiling based on a conventional flow cytometer and an emerging CRISPR/Cas system. By using our strategy, the featured membrane protein distributions of different cancer cell-derived exosomes can be figured out, which can clearly distinguish plasma samples of breast cancer patients from those of healthy people. This work paves new ways for exosome profiling and liquid biopsy and expands the understanding of TdT, holding great significance in developing TdT-based sensing systems as well as establishing protein/nucleic acid hybrid biomaterials.

Knowledge-Driven Approaches to Create the MTox700+ Metabolite Panel for Predicting Toxicity.

Endogenous metabolite levels describe the molecular phenotype that is most downstream from chemical exposure. Consequently, quantitative changes in metabolite levels have the potential to predict mode-of-action and adversity, with regulatory toxicology predicated on the latter. However, toxicity-related metabolic biomarker resources remain highly fragmented and incomplete. Although development of the S1500+ gene biomarker panel has accelerated the application of transcriptomics to toxicology, a similar initiative for metabolic biomarkers is lacking. Our aim was to define a publicly available metabolic biomarker panel, equivalent to S1500+, capable of predicting pathway perturbations and/or adverse outcomes. We conducted a systematic review of multiple toxicological resources, yielding 189 proposed metabolic biomarkers from existing assays (BASF, Bowes-44, and Tox21), 342 biomarkers from databases (Adverse Outcome Pathway Wiki, Comparative Toxicogenomics Database, QIAGEN Ingenuity Pathway Analysis, and Toxin and Toxin-Target Database), and 435 biomarkers from the literature. Evidence mapping across all 8 resources generated a panel of 722 metabolic biomarkers for toxicology (MTox700+), of which 462 (64%) are associated with molecular pathways and 575 (80%) with adverse outcomes. Comparing MTox700+ and S1500+ revealed that 418 (58%) metabolic biomarkers associate with pathways shared across both panels, with further metabolites mapping to unique pathways. Metabolite reference standards are commercially available for 646 (90%) of the panel metabolites, and assays exist for 578 (80%) of these biomarkers. This study has generated a publicly available metabolic biomarker panel for toxicology, which through its future laboratory deployment, is intended to help build foundational knowledge to support the generation of molecular mechanistic data for chemical hazard assessment.

ISA API: An open platform for interoperable life science experimental metadata.

BACKGROUND: The Investigation/Study/Assay (ISA) Metadata Framework is an established and widely used set of open source community specifications and software tools for enabling discovery, exchange, and publication of metadata from experiments in the life sciences. The original ISA software suite provided a set of user-facing Java tools for creating and manipulating the information structured in ISA-Tab-a now widely used tabular format. To make the ISA framework more accessible to machines and enable programmatic manipulation of experiment metadata, the JSON serialization ISA-JSON was developed. RESULTS: In this work, we present the ISA API, a Python library for the creation, editing, parsing, and validating of ISA-Tab and ISA-JSON formats by using a common data model engineered as Python object classes. We describe the ISA API feature set, early adopters, and its growing user community. CONCLUSIONS: The ISA API provides users with rich programmatic metadata-handling functionality to support automation, a common interface, and an interoperable medium between the 2 ISA formats, as well as with other life science data formats required for depositing data in public databases.

Progress towards an OECD reporting framework for transcriptomics and metabolomics in regulatory toxicology.

Omics methodologies are widely used in toxicological research to understand modes and mechanisms of toxicity. Increasingly, these methodologies are being applied to questions of regulatory interest such as molecular point-of-departure derivation and chemical grouping/read-across. Despite its value, widespread regulatory acceptance of omics data has not yet occurred. Barriers to the routine application of omics data in regulatory decision making have been: 1) lack of transparency for data processing methods used to convert raw data into an interpretable list of observations; and 2) lack of standardization in reporting to ensure that omics data, associated metadata and the methodologies used to generate results are available for review by stakeholders, including regulators. Thus, in 2017, the Organisation for Economic Co-operation and Development (OECD) Extended Advisory Group on Molecular Screening and Toxicogenomics (EAGMST) launched a project to develop guidance for the reporting of omics data aimed at fostering further regulatory use. Here, we report on the ongoing development of the first formal reporting framework describing the processing and analysis of both transcriptomic and metabolomic data for regulatory toxicology. We introduce the modular structure, content, harmonization and strategy for trialling this reporting framework prior to its publication by the OECD.

Survivors' conceptualizations of human trafficking prevention; An exploratory study.

The purpose of this study was to explicate a conceptual framework for the prevention of human trafficking from the perspective of those most impacted: human trafficking survivors. In doing so establishing an empirical foundation for human trafficking prevention research. To achieve this aim, researchers employed Group Concept Mapping (GCM). GCM is an integrated, mixed-method, research design that analyzes qualitative data via quantitative approaches, namely multidimensional scaling and hierarchical cluster analyses. All participants (N = 35) identified as human trafficking survivors from one of four states in the United States. Results indicate that survivors in this sample conceptualize prevention via a 10-cluster solution. Furthermore survivors rated the cluster on Education and Awareness (9) as the most Important (4.60), as well as the most Feasible (4.28). This paper will review extant literature related to human trafficking, explicate results from this study, and discuss pragmatic prevention implications related to findings.

Predictors of New-Onset Physical Restraint Use in Critically Ill Adults.

BACKGROUND: Physical restraints are frequently used for intensive care patients and are associated with substantial morbidity. The effects of common evidence-based critical care interventions on use of physical restraints remain unclear. OBJECTIVE: To identify independent predictors of new-onset use of physical restraints in critically ill adults. METHODS: Secondary analysis of a prospective cohort study involving 5 adult intensive care units in a tertiary care medical center in the United States. Use of physical restraints was determined via daily in-person assessments and medical record review. Mixed-effects logistic regression analysis was used to examine factors associated with new-onset use of physical restraints, adjusting for covariates and within-subject correlation among intensive care unit days. RESULTS: Of 145 patients who were free of physical restraints within 48 hours of intensive care unit admission, 24 (16.6%) had restraints newly applied during their stay. In adjusted models, delirium (odds ratio [OR], 5.09; 95% CI, 1.83-14.14), endotracheal tube presence (OR, 3.47; 95% CI, 1.22-9.86), and benzodiazepine administration (OR, 3.17; 95% CI, 1.28-7.81) significantly increased the odds of next-day use of physical restraints. Tracheostomy was associated with significantly lowered odds of next-day restraint use (OR, 0.13; 95% CI, 0.02-0.73). Compared with patients with a target sedation level, patients who were in a coma (OR, 2.56; 95% CI, 0.80-8.18) or deeply sedated (OR, 2.53; 95% CI, 0.91-7.08) had higher odds of next-day use of physical restraints, and agitated patients (OR, 0.08; 95% CI, 0.00-2.07) were less likely to experience restraint use. CONCLUSION: Several potentially modifiable risk factors are associated with next-day use of physical restraints.

Intraosseous Administration of Hypertonic Saline in Acute Brain-Injured Patients: A Prospective Case Series and Literature Review.

BACKGROUND: Central venous catheters are often used to administer hypertonic saline (HTS) but might be associated with serious complications. Intraosseous (IO) access is an alternative method of medication and fluid delivery which is not associated with life-threatening complications and can be inserted faster than CVCs. METHODS: A prospective case series was conducted on critically ill neurological patients that did not have central venous access, and for whom 3% HTS was indicated. Nonverbal indicators of pain were measured using the critical care pain observation tool. The pain score and serum sodium levels were collected at baseline, at 2, 6, 12, 18, and 24 hours after administration of 3% HTS using IO access. The area surrounding the IO insertion site was monitored for needle placement, extravasation, and tissue damage. RESULTS: Five patients were enrolled. Three had an IO placed in the proximal humerus and 2 in the proximal tibia. Most patients did not have nonverbal indicators of pain during insertion and initial bolus. Serum sodium levels increased appropriately, as determined by the care providers. There were no cases of device dislodgement, extravasation, infection, soft tissue injury, or other local complications. CONCLUSIONS: In this prospective case series, IO administration of 3% HTS was feasible, well-tolerated on the basis of nonverbal indicators of pain in the majority of patients and resulted in an appropriate rise in serum sodium levels. IO fills a niche among vascular access options for HTS, in emergent neurological situations when central venous access is not readily available or peripheral intravenous access is difficult to obtain.

Time-Gated Luminescent In Situ Hybridization (LISH): Highly Sensitive Detection of Pathogenic Staphylococcus aureus.

We describe simple direct conjugation of a single TEGylated Europium chelate to DNA that binds to intracellular rRNA and is then detected using a homogeneous luminescent in situ hybridisation (LISH) technique. As a proof-of-principle, Staphylococcus aureus (S. aureus) was selected as a model for our study to show the ability of this probe to bind to intracellular 16S ribosomal rRNA. A highly purified Europium chelate conjugated oligonucleotide probe complementary to an rRNA sequence-specific S. aureus was prepared and found to be soluble and stable in aqueous solution. The probe was able to bind specifically to S. aureus via in situ hybridisation to differentiate S. aureus from a closely related but less pathogenic Staphylococcus species (S. epidermidis). A time-gated luminescent (TGL) microscope system was used to generate the high signal-to-noise ratio (SNR) images of the S. aureus. After excitation (365 nm, Chelate λmax = 335 nm), the long-lived (Eu3+) luminescent emission from the probe was detected without interference from natural background autofluorescence typically seen in biological samples. The luminescent images were found to have 6 times higher SNR or sensitivity compared to the fluorescent images using conventional fluorophore Alexa Fluor 488. The TEGylated Europium chelate -oligo probe stained S. aureus with mean signal intensity 3.5 times higher than the threshold level of signal from S. epidermidis (with SNR 8 times higher). A positive control probe (EUB338-BHHTEGST-Eu3+) has mean signal intensity for S. aureus and S. epidermidis equally 3.2 times higher than the threshold of signal for a negative NON-EUB338 control probe. The direct conjugation of a single Europium chelate to DNA provides simplicity and improvement over existing bovine serum albumin (BSA)/streptavidin/biotinylated DNA platforms for multi-attachment of Europium chelate per DNA and more importantly makes it feasible for hybridisation to intracellular RNA targets. This probe has great potential for highly sensitive homogeneous in situ hybridisation detection of the vast range of intracellular DNA targets.

Multidrug- and colistin-resistant Salmonella enterica 4,[5],12:i:- sequence type 34 carrying the mcr-3.1 gene on the IncHI2 plasmid recovered from a human.

A colistin-resistant Salmonella enterica 4, [5],12:i:- sequence type (ST) 34 harbouring mcr-3.1 was recovered from a patient who travelled to China 2 weeks prior to diarrhoea onset. Genomic analysis revealed the presence of the mcr-3.1 gene located in the globally disseminated IncHI2 plasmid, highlighting the intercontinental dissemination of the colistin-resistant S. enterica 4, [5],12:i:- ST34 pandemic clone.

Metabolomic method to detect a metabolite corona on amino-functionalized polystyrene nanoparticles.

Protein coronas on nanoparticles (NPs) affect their physicochemical properties, cellular uptake, and toxicity, and have been described extensively. To date, studies of the occurrence of small molecule (metabolite) coronas are limited. We sought to determine whether a metabolite corona forms on NPs, using high-sensitivity metabolomics combined with a model system for freshwater ecotoxicology (Daphnia magna feeding on Chlorella vulgaris). Using amino-functionalized polystyrene NPs (NH2-pNPs), we showed the impact of this material on Daphnia feeding to provide a rationale for the detailed molecular investigations. We then employed a targeted LC-MS/MS approach for sodium dodecyl sulfate (SDS) as an analog to signaling molecules known to occur in our freshwater model system and optimized a corona extraction method for this representative metabolite. Next, we performed an untargeted discovery-based metabolomics study - using high-sensitivity nanoelectrospray direct infusion mass spectrometry (DIMS) - to enable an unbiased assessment of the metabolite corona of NH2-pNPs in the freshwater model system. Our results demonstrate that SDS was successfully recovered from NH2-pNPs, confirming that the extraction protocol was fit-for-purpose. Untargeted DIMS metabolomics reproducibly detected 100 s of small molecule peaks extracted from NH2-pNPs exposed to conditioned media from the D. magna-C. vulgaris model system. Attempts to annotate these extracted metabolites, including by using van Krevelen and Kendrick Mass Defect plots, indicate a diverse range of metabolites that were not clustered into any particular class. Overall we demonstrate the existence of an ecologically relevant metabolite corona on the surface of NPs through application of a high-sensitivity, untargeted mass spectrometry metabolomics workflow.

Diagnostic Reasoning and Cognitive Biases of Nurse Practitioners.

BACKGROUND: Diagnostic reasoning is often used colloquially to describe the process by which nurse practitioners and physicians come to the correct diagnosis, but a rich definition and description of this process has been lacking in the nursing literature. METHOD: A literature review was conducted with theoretical sampling seeking conceptual insight into diagnostic reasoning. RESULTS: Four common themes emerged: Cognitive Biases and Debiasing Strategies, the Dual Process Theory, Diagnostic Error, and Patient Harm. Relevant cognitive biases are discussed, followed by debiasing strategies and application of the dual process theory to reduce diagnostic error and harm. CONCLUSION: The accuracy of diagnostic reasoning of nurse practitioners may be improved by incorporating these items into nurse practitioner education and practice. [J Nurs Educ. 2018;57(4):203-208.].