Coupled Single-Cell CRISPR Screening and Epigenomic Profiling Reveals Causal Gene Regulatory Networks.

Here, we present Perturb-ATAC, a method that combines multiplexed CRISPR interference or knockout with genome-wide chromatin accessibility profiling in single cells based on the simultaneous detection of CRISPR guide RNAs and open chromatin sites by assay of transposase-accessible chromatin with sequencing (ATAC-seq). We applied Perturb-ATAC to transcription factors (TFs), chromatin-modifying factors, and noncoding RNAs (ncRNAs) in ∼4,300 single cells, encompassing more than 63 genotype-phenotype relationships. Perturb-ATAC in human B lymphocytes uncovered regulators of chromatin accessibility, TF occupancy, and nucleosome positioning and identified a hierarchy of TFs that govern B cell state, variation, and disease-associated cis-regulatory elements. Perturb-ATAC in primary human epidermal cells revealed three sequential modules of cis-elements that specify keratinocyte fate. Combinatorial deletion of all pairs of these TFs uncovered their epistatic relationships and highlighted genomic co-localization as a basis for synergistic interactions. Thus, Perturb-ATAC is a powerful strategy to dissect gene regulatory networks in development and disease.

The genetics of human performance.

Human physiology is likely to have been selected for endurance physical activity. However, modern humans have become largely sedentary, with physical activity becoming a leisure-time pursuit for most. Whereas inactivity is a strong risk factor for disease, regular physical activity reduces the risk of chronic disease and mortality. Although substantial epidemiological evidence supports the beneficial effects of exercise, comparatively little is known about the molecular mechanisms through which these effects operate. Genetic and genomic analyses have identified genetic variation associated with human performance and, together with recent proteomic, metabolomic and multi-omic analyses, are beginning to elucidate the molecular genetic mechanisms underlying the beneficial effects of physical activity on human health.

Cutaneous immune-related adverse events from immune checkpoint inhibitor therapy: Moving beyond "maculopapular rash".

Uncoupling toxicity from therapeutic effect lies at the foundation of the current state of the field of cutaneous immune-related adverse events to immune checkpoint inhibitor therapy. This will be achieved through understanding the drivers of toxicity, tumor response, and resistance via large, well-powered population-level studies, institutional cohort data, and cellular-level data. Increasing diagnostic specificity through the application of consensus disease definitions has the power to improve clinical care and each approach to research. Cutaneous immune-related adverse events are associated with increased survival, and their treatment must invoke the maintenance of a delicate balance between immunosuppression, anti-tumor effect of immune checkpoint inhibitor therapy, and quality of life. The multidisciplinary care of cancer patients with adverse events is critical to optimizing clinical and translational research outcomes and, as such, dermatologists are vital to moving the study of cutaneous adverse events forward.

Collective cell migration is spatiotemporally regulated during mammary epithelial bifurcation.

Branched epithelial networks are generated through an iterative process of elongation and bifurcation. We sought to understand bifurcation of the mammary epithelium. To visualize this process, we utilized three-dimensional (3D) organotypic culture and time-lapse confocal microscopy. We tracked cell migration during bifurcation and observed local reductions in cell speed at the nascent bifurcation cleft. This effect was proximity dependent, as individual cells approaching the cleft reduced speed, whereas cells exiting the cleft increased speed. As the cells slow down, they orient both migration and protrusions towards the nascent cleft, while cells in the adjacent branches orient towards the elongating tips. We next tested the hypothesis that TGF-ß signaling controls mammary branching by regulating cell migration. We first validated that addition of TGF-ß1 (TGFB1) protein increased cleft number, whereas inhibition of TGF-ß signaling reduced cleft number. Then, consistent with our hypothesis, we observed that pharmacological inhibition of TGF-ß1 signaling acutely decreased epithelial migration speed. Our data suggest a model for mammary epithelial bifurcation in which TGF-ß signaling regulates cell migration to determine the local sites of bifurcation and the global pattern of the tubular network.

Bcl3 Phosphorylation by Akt, Erk2, and IKK Is Required for Its Transcriptional Activity.

Unlike prototypical IκB proteins, which are inhibitors of NF-κB RelA, cRel, and RelB dimers, the atypical IκB protein Bcl3 is primarily a transcriptional coregulator of p52 and p50 homodimers. Bcl3 exists as phospho-protein in many cancer cells. Unphosphorylated Bcl3 acts as a classical IκB-like inhibitor and removes p50 and p52 from bound DNA. Neither the phosphorylation site(s) nor the kinase(s) phosphorylating Bcl3 is known. Here we show that Akt, Erk2, and IKK1/2 phosphorylate Bcl3. Phosphorylation of Ser33 by Akt induces switching of K48 ubiquitination to K63 ubiquitination and thus promotes nuclear localization and stabilization of Bcl3. Phosphorylation by Erk2 and IKK1/2 of Ser114 and Ser446 converts Bcl3 into a transcriptional coregulator by facilitating its recruitment to DNA. Cells expressing the S114A/S446A mutant have cellular proliferation and migration defects. This work links Akt and MAPK pathways to NF-κB through Bcl3 and provides mechanistic insight into how Bcl3 functions as an oncoprotein through collaboration with IKK1/2, Akt, and Erk2.

A Decade of Chronic Norovirus Infection Surveillance at the NIH Clinical Research Center: Clinical Characteristics, Molecular Epidemiology, and Replication.

BACKGROUND: Noroviruses are an important viral cause of chronic diarrhea in immunocompromised individuals. METHOD: We collected norovirus-positive stool samples (n=448) from immunocompromised patients (n=88) at the National Institutes of Health Clinical Research Center, U.S. from 2010-2022. We assessed clinical characteristics of the cohort, norovirus molecular epidemiology, and infectivity of norovirus specimens in human intestinal enteroids (HIEs) monolayers. RESULTS: Thirty-nine of the 88 patients had sequential stool samples that allowed documentation of chronic norovirus infection with shedding levels ranging from 104 to 1011 genome copies/g of stool. The majority with confirmed chronic norovirus infection in this cohort (32/39, 82%) had clinical evidence of an inborn error of immunity (13 identified monogenic diseases), most with combined immunodeficiency (15 of 32) or common variable immunodeficiency (11 of 32). Noroviruses detected in the cohort were genetically diverse: both Genogroup I (GI.2, GI.3, GI.5, and GI.6) and Genogroup II (GII.1-GII.4, GII.6, GII.7, GII.12, GII.14, and GII.17) genotypes were detected, with GII.4 variants (Osaka, Apeldoorn, Den Haag, New Orleans, and Sydney) predominant (51 of 88, 57.9%). Viruses belonging to the GII.4 Sydney variant group that replicated in HIEs (n=9) showed a higher fold-increase in RNA genome copies during infection compared to others that replicated. CONCLUSIONS: Genetically and biologically diverse noroviruses established chronic infection in individuals with both inborn and acquired immunologic defects enrolled in an NIH surveillance study spanning 12 years, demonstrating the unique nature of each virus and host interaction.

Redefining the molecular rejection states in 3230 heart transplant biopsies: Relationships to parenchymal injury and graft survival.

The first-generation Molecular Microscope (MMDx) system for heart transplant endomyocardial biopsies used expression of rejection-associated transcripts (RATs) to diagnose not only T cell-mediated rejection (TCMR) and antibody-mediated rejection (ABMR) but also acute injury. However, the ideal system should detect rejection without being influenced by injury, to permit analysis of the relationship between rejection and parenchymal injury. To achieve this, we developed a new rejection classification in an expanded cohort of 3230 biopsies: 1641 from INTERHEART (ClinicalTrials.gov NCT02670408), plus 1589 service biopsies added to improve the power of the machine learning algorithms. The new system used 6 rejection classifiers instead of RATs and generated 7 rejection archetypes: No rejection, 48%; Minor, 24%; TCMR1, 2.3%; TCMR2, 2.7%; TCMR/mixed, 2.7%; early-stage ABMR, 3.9%; and fully developed ABMR, 16%. Using rejection classifiers eliminated cross-reactions with acute injury, permitting separate assessment of rejection and injury. TCMR was associated with severe-recent injury and late atrophy-fibrosis and rarely had normal parenchyma. ABMR was better tolerated, seldom producing severe injury, but in later biopsies was often associated with atrophy-fibrosis, indicating long-term risk. Graft survival and left ventricular ejection fraction were reduced not only in hearts with TCMR but also in hearts with severe-recent injury and atrophy-fibrosis, even without rejection.

GRASP reconstruction amplified with view-sharing and KWIC filtering reduces underestimation of peak velocity in highly-accelerated real-time phase-contrast MRI: A preliminary evaluation in pediatric patients with congenital heart disease.

PURPOSE: To develop a highly-accelerated, real-time phase contrast (rtPC) MRI pulse sequence with 40 fps frame rate (25 ms effective temporal resolution). METHODS: Highly-accelerated golden-angle radial sparse parallel (GRASP) with over regularization may result in temporal blurring, which in turn causes underestimation of peak velocity. Thus, we amplified GRASP performance by synergistically combining view-sharing (VS) and k-space weighted image contrast (KWIC) filtering. In 17 pediatric patients with congenital heart disease (CHD), the conventional GRASP and the proposed GRASP amplified by VS and KWIC (or GRASP + VS + KWIC) reconstruction for rtPC MRI were compared with respect to clinical standard PC MRI in measuring hemodynamic parameters (peak velocity, forward volume, backward volume, regurgitant fraction) at four locations (aortic valve, pulmonary valve, left and right pulmonary arteries). RESULTS: The proposed reconstruction method (GRASP + VS + KWIC) achieved better effective spatial resolution (i.e., image sharpness) compared with conventional GRASP, ultimately reducing the underestimation of peak velocity from 17.4% to 6.4%. The hemodynamic metrics (peak velocity, volumes) were not significantly (p > 0.99) different between GRASP + VS + KWIC and clinical PC, whereas peak velocity was significantly (p < 0.007) lower for conventional GRASP. RtPC with GRASP + VS + KWIC also showed the ability to assess beat-to-beat variation and detect the highest peak among peaks. CONCLUSION: The synergistic combination of GRASP, VS, and KWIC achieves 25 ms effective temporal resolution (40 fps frame rate), while minimizing the underestimation of peak velocity compared with conventional GRASP.

Incorporation of view sharing and KWIC filtering into GRASP-Pro improves spatial resolution of single-shot, multi-TI, late gadolinium enhancement MRI.

While single-shot late gadolinium enhancement (LGE) is useful for imaging patients with arrhythmia and/or dyspnea, it produces low spatial resolution. One approach to improve spatial resolution is to accelerate data acquisition using compressed sensing (CS). Our previous work described a single-shot, multi-inversion time (TI) LGE pulse sequence using radial k-space sampling and CS, but over-regularization resulted in significant image blurring that muted the benefits of data acceleration. The purpose of the present study was to improve the spatial resolution of the single-shot, multi-TI LGE pulse sequence by incorporating view sharing (VS) and k-space weighted contrast (KWIC) filtering into a GRASP-Pro reconstruction. In 24 patients (mean age = 61 ± 16 years; 9/15 females/males), we compared the performance of our improved multi-TI LGE and standard multi-TI LGE, where clinical standard LGE was used as a reference. Two clinical raters independently graded multi-TI images and clinical LGE images visually on a five-point Likert scale (1, nondiagnostic; 3, clinically acceptable; 5, best) for three categories: the conspicuity of myocardium or scar, artifact, and noise. The summed visual score (SVS) was defined as the sum of the three scores. Myocardial scar volume was quantified using the full-width at half-maximum method. The SVS was not significantly different between clinical breath-holding LGE (median 13.5, IQR 1.3) and multi-TI LGE (median 12.5, IQR 1.6) (P = 0.068). The myocardial scar volumes measured from clinical standard LGE and multi-TI LGE were strongly correlated (coefficient of determination, R2 = 0.99) and in good agreement (mean difference = 0.11%, lower limit of the agreement = -2.13%, upper limit of the agreement = 2.34%). The inter-rater agreement in myocardial scar volume quantification was strong (intraclass correlation coefficient = 0.79). The incorporation of VS and KWIC into GRASP-Pro improved spatial resolution. Our improved 25-fold accelerated, single-shot LGE sequence produces clinically acceptable image quality, multi-TI reconstruction, and accurate myocardial scar volume quantification.

Dynamics of Chromatin Accessibility During Hematopoietic Stem Cell Differentiation Into Progressively Lineage-Committed Progeny.

Epigenetic mechanisms regulate the multilineage differentiation capacity of hematopoietic stem cells (HSCs) into a variety of blood and immune cells. Mapping the chromatin dynamics of functionally defined cell populations will shed mechanistic insight into 2 major, unanswered questions in stem cell biology: how does epigenetic identity contribute to a cell type's lineage potential, and how do cascades of chromatin remodeling dictate ensuing fate decisions? Our recent work revealed evidence of multilineage gene priming in HSCs, where open cis-regulatory elements (CREs) exclusively shared between HSCs and unipotent lineage cells were enriched for DNA binding motifs of known lineage-specific transcription factors. Oligopotent progenitor populations operating between the HSCs and unipotent cells play essential roles in effecting hematopoietic homeostasis. To test the hypothesis that selective HSC-primed lineage-specific CREs remain accessible throughout differentiation, we used ATAC-seq to map the temporal dynamics of chromatin remodeling during progenitor differentiation. We observed epigenetic-driven clustering of oligopotent and unipotent progenitors into distinct erythromyeloid and lymphoid branches, with multipotent HSCs and MPPs associating with the erythromyeloid lineage. We mapped the dynamics of lineage-primed CREs throughout hematopoiesis and identified both unique and shared CREs as potential lineage reinforcement mechanisms at fate branch points. Additionally, quantification of genome-wide peak count and size revealed overall greater chromatin accessibility in HSCs, allowing us to identify HSC-unique peaks as putative regulators of self-renewal and multilineage potential. Finally, CRISPRi-mediated targeting of ATACseq-identified putative CREs in HSCs allowed us to demonstrate the functional role of selective CREs in lineage-specific gene expression. These findings provide insight into the regulation of stem cell multipotency and lineage commitment throughout hematopoiesis and serve as a resource to test functional drivers of hematopoietic lineage fate.

How Are We Teaching Advocacy? A National Survey of Internal Medicine Residency Program Directors.

BACKGROUND: Although internal medicine (IM) physicians accept public advocacy as a professional responsibility, there is little evidence that IM training programs teach advocacy skills. The prevalence and characteristics of public advocacy curricula in US IM residency programs are unknown. OBJECTIVES: To describe the prevalence and characteristics of curricula in US IM residencies addressing public advocacy for communities and populations; to describe barriers to the provision of such curricula. DESIGN: Nationally representative, web-based, cross-sectional survey of IM residency program directors with membership in an academic professional association. PARTICIPANTS: A total of 276 IM residency program directors (61%) responded between August and December 2022. MAIN MEASUREMENTS: Percentage of US IM residency programs that teach advocacy curricula; characteristics of advocacy curricula; perceptions of barriers to teaching advocacy. KEY RESULTS: More than half of respondents reported that their programs offer no advocacy curricula (148/276, 53.6%). Ninety-five programs (95/276, 34.4%) reported required advocacy curricula; 33 programs (33/276, 12%) provided curricula as elective only. The content, structure, and teaching methods of advocacy curricula in IM programs were heterogeneous; experiential learning in required curricula was low (23/95, 24.2%) compared to that in elective curricula (51/65, 78.5%). The most highly reported barriers to implementing or improving upon advocacy curricula (multiple responses allowed) were lack of faculty expertise in advocacy (200/276, 72%), inadequate faculty time (190/276, 69%), and limited curricular flexibility (148/276, 54%). CONCLUSION: Over half of US IM residency programs offer no formal training in public advocacy skills and many reported lack of faculty expertise in public advocacy as a barrier. These findings suggest many IM residents are not taught how to advocate for communities and populations. Further, less than one-quarter of required curricula in public advocacy involves experiential learning.

Assessment of immunosuppression induction with basiliximab compared to antithymocyte-globulin in adult heart transplant patients.

BACKGROUND: Patients undergoing heart transplants are at risk of rejection which can have significant morbidity and mortality. Induction immunosuppression at the time of transplant reduces the early risk and has additional benefits. The induction agent of choice within our program was changed from rabbit antithymocyte-globulin (rATG) to basiliximab, so it was necessary to evaluate whether this had any impact on patient outcomes. OBJECTIVES: Our primary objective was to describe rejection, infection, and other outcomes in adult heart transplant patients at the University of Alberta Hospital in Edmonton, Canada. METHODS: This study was a nonrandomized, retrospective cohort study. RESULTS: Sixty-three patients were included with median ages 50 years versus 54 years. More female patients received rATG (20% vs. 42.4%). The most common indication for transplant in both cohorts was ICM (63.3% vs. 57.6%). Patients who received rATG had significantly higher PRA (0% vs. 43%, p < .001). Acute rejection episodes were similar between basiliximab and rATG at 3 months (16.7% vs. 15.1%; p = 1.0) and 6-months (30.0% vs. 18.1%; p = .376). Infections were not statistically different with basiliximab compared to rATG at 3-months, 43.3% vs. 63.6% and at 6-months 60.0% vs. 66.7%). There were no fatalities in either group. CONCLUSIONS: Our study did not demonstrate differences in rejection with basiliximab compared to rATG. Mortality did not differ, but basiliximab-treated patients had fewer infections and infection-related hospitalizations than those treated with rATG. Larger studies with longer durations are needed to more completely describe the differences in rejection and infectious outcomes.

Lack of Association Between Donor-Derived Cell-Free DNA and Cardiac Allograft Vasculopathy.

Cardiac allograft vasculopathy (CAV) is a leading cause of death after heart transplantation (HT). We evaluated donor-derived cell-free DNA (dd-cfDNA) as a noninvasive biomarker of CAV development after HT. The INSPIRE registry at the Intermountain Medical Center was queried for stored plasma samples from HT patients with and without CAV. At Stanford University, HT patients with CAV (cases) and without CAV (controls) were enrolled prospectively, and blood samples were collected. All the samples were analyzed for dd-cfDNA using the AlloSure assay (CareDx, Inc.). CAV was defined per the ISHLT 2010 standardized classification system. Univariate associations between patient demographics and clinical characteristics and their CAV grade were tested using chi-square and Wilcoxon rank sum tests. Associations between their dd-cfDNA levels and CAV grades were examined using a nonparametric Kruskal-Wallis test. A total of 69 pts were included, and 101 samples were analyzed for dd-cfDNA. The mean age at sample collection was 58.6 ± 13.7 years; 66.7% of the patients were male, and 81% were White. CAV 0, 1, 2, and 3 were present in 37.6%, 22.8%, 22.8%, and 16.8% of included samples, respectively. The median dd-cfDNA level was 0.13% (0.06, 0.33). The median dd-cfDNA level was not significantly different between CAV (-) and CAV (+): 0.09% (0.05%-0.32%) and 0.15% (0.07%-0.33%), respectively, p = 0.25 and with similar results across all CAV grades. In our study, dd-cfDNA levels did not correlate with the presence of CAV and did not differ across CAV grades. As such, dd-cfDNA does not appear to be a reliable noninvasive biomarker for CAV surveillance.

Safety and Effectiveness of Track Cauterization for Lung Cryoablation.

PURPOSE: To evaluate the safety and effectiveness of track cauterization for lung cryoablation through comparison of postprocedural adverse event (AE) rates. MATERIALS AND METHODS: Fifty-nine patients who underwent 164 percutaneous lung cryoablation procedures between 2013 and 2018 were included in this retrospective study. The study cohort was subdivided by whether track cauterization was conducted or not at the end of the procedure. The study cohort was also subdivided by the number of probes (1-2 probes vs 3-4 probes). Postablation AE rates were assessed by immediate and delayed (at 1 month or later) AEs, pneumothorax, hemothorax, pleural effusion, and whether intervention was required. Univariate and multivariate logistic regression analyses were used to compare differences in AE rates. RESULTS: Patients who underwent procedures with track cautery were 2.6 times less likely to exhibit pleural effusion (P = .017). Patients who underwent procedures conducted with a higher number of probes were 3.8 times more likely to receive interventions (P < .001), 1.6 times more likely to experience pneumothorax (P = .037), and 2.1 times more likely to experience pleural effusion (P = .003). History of lung surgery, increased number of probes, size of the probe, and absence of track cautery were noted to be significant predictors of AEs and need for interventions (all P < .05). CONCLUSIONS: Track cauterization in lung cryoablation was proven to reduce pleural effusion, but no difference in pneumothorax or delayed AEs was noted. The use of fewer probes was associated with a lower rate of AEs.

Patient-Specific Prediction of Immediate Phase Lung Microwave Ablation Zone Size.

PURPOSE: To investigate the effect of patient and tumor-specific characteristics on the size of immediate phase lung microwave ablation (MWA) zone and establish a prediction model. MATERIALS AND METHODS: This institutional review board (IRB)-approved, Health Insurance Portability and Accountability Act (HIPAA)-compliant cohort included 164 lesions from 99 patients who underwent computed tomography (CT)-guided lung MWA, and the 2-dimensional elliptical ground-glass opacity ablation zone was measured. Duration, maximum temperature, tumor depth, presence of emphysema, history of ipsilateral lung ablation, surgery, and radiotherapy were recorded. K-fold cross validation with k = 5 and Least Absolute Shrinkage and Selection Operator were used to build prediction models for the major and minor axes and area of the ablation zone. RESULTS: The median of immediate phase ablation duration was 2 minutes (interquartile range, 1.5-4.25 minutes) with 65 W of power for all ablations. The mean major and minor axes and area of ablation zone were 3.1 cm (SD ± 0.6), 2.0 cm (SD ± 0.5), and 5.1 cm2 (SD ± 2.1), respectively. The major and minor axes and area of immediate phase ablation zone dimensions were significantly associated with duration (P < .001, P < .001, and P < .001, respectively), maximum temperature (P < .001, P < .001, and P < .001, respectively), tumor depth (P = .387, P < .001, and P < .001, respectively), history of ipsilateral lung ablation (P = .008, P = .286, and P = .076, respectively), and lung radiotherapy (P = .001, P = .042, and P = .015, respectively). The prediction model showed R2 values for major and minor axes and area of the ablation zone to be 0.50, 0.45, and 0.53, respectively. CONCLUSIONS: Duration of ablation, maximum temperature, tumor depth, history of ipsilateral lung ablation, surgery, and radiotherapy were significantly associated with the ablation zone dimensions and size and can be used to build the prediction model to approximate the immediate phase lung MWA zone.

Technical Feasibility and Safety of Image-Guided Biphasic Monopolar Pulsed Electric Field Ablation of Metastatic and Primary Malignancies.

PURPOSE: To assess the technical feasibility and safety of image-guided percutaneous biphasic monopolar pulsed electric field (PEF) ablation of primary and metastatic tumors. MATERIALS AND METHODS: With institutional review board (IRB) approval and Health Insurance Portability and Accountability Act (HIPAA) compliance, this retrospective, single-institution study cohort of 17 patients (mean age, 53.5 years; range, 20-94 years) with overall progressive disease underwent 26 PEF ablation procedures for 30 metastatic (90%) and primary (10%) target lesions in the thorax (n = 20), abdomen (n = 7), and head and neck (n = 3). Concurrent systemic therapy was used in 14 of the 17 patients (82%). Follow-up imaging was scheduled for 1, 3, and 6 months after PEF ablation, and target and off-target lesion sizes were recorded. The overall response was assessed by the Response Evaluation Criteria in Solid Tumors (RECIST) 1.1 criteria with imaging immediately before PEF serving as baseline. Adverse events (AEs) were determined by the Society of Interventional Radiology (SIR) classification. RESULTS: PEF ablation procedures were well tolerated and technically feasible for all 17 patients. The mean initial sizes of the target and off-target tumors were 2.6 cm (standard deviation [SD] ± 1.5; range, 0.4-6.9 cm) and 2.2 cm (SD ± 1.1; range, 1.0-5.2 cm), respectively. Overall, 15 of the 30 (50%) target lesions and 12 of the 24 (50%) off-target lesions were unchanged or decreased in size at the patient's last follow-up. Eight patients had overall stable disease (47%) at the last follow-up. Of the 26 AEs, there were 9 mild (35%) and 1 moderate (4%) AE. CONCLUSIONS: All PEF procedures were technically feasible with 1 moderate AE and stable disease for 47% of patients with a median follow-up period of 3 months.

SCMR expert consensus statement for cardiovascular magnetic resonance of patients with a cardiac implantable electronic device.

Cardiovascular magnetic resonance (CMR) is a proven imaging modality for informing diagnosis and prognosis, guiding therapeutic decisions, and risk stratifying surgical intervention. Patients with a cardiac implantable electronic device (CIED) would be expected to derive particular benefit from CMR given high prevalence of cardiomyopathy and arrhythmia. While several guidelines have been published over the last 16 years, it is important to recognize that both the CIED and CMR technologies, as well as our knowledge in MR safety, have evolved rapidly during that period. Given increasing utilization of CIED over the past decades, there is an unmet need to establish a consensus statement that integrates latest evidence concerning MR safety and CIED and CMR technologies. While experienced centers currently perform CMR in CIED patients, broad availability of CMR in this population is lacking, partially due to limited availability of resources for programming devices and appropriate monitoring, but also related to knowledge gaps regarding the risk-benefit ratio of CMR in this growing population. To address the knowledge gaps, this SCMR Expert Consensus Statement integrates consensus guidelines, primary data, and opinions from experts across disparate fields towards the shared goal of informing evidenced-based decision-making regarding the risk-benefit ratio of CMR for patients with CIEDs.

Defining blood hematology reference values in female pig-tailed macaques (Macaca nemestrina) using the Isolation Forest algorithm.

BACKGROUND: Pig-tailed macaques (PTMs) are commonly used as preclinical models to assess antiretroviral drugs for HIV prevention research. Drug toxicities and disease pathologies are often preceded by changes in blood hematology. To better assess the safety profile of pharmaceuticals, we defined normal ranges of hematological values in PTMs using an Isolation Forest (iForest) algorithm. METHODS: Eighteen female PTMs were evaluated. Blood was collected 1-24 times per animal for a total of 159 samples. Complete blood counts were performed, and iForest was used to analyze the hematology data to detect outliers. RESULTS: Median, IQR, and ranges were calculated for 13 hematology parameters. From all samples, 22 outliers were detected. These outliers were excluded from the reference index. CONCLUSIONS: Using iForest, we defined a normal range for hematology parameters in female PTMs. This reference index can be a valuable tool for future studies evaluating drug toxicities in PTMs.

Biomarkers of Airway Disease, Barrett's and Underdiagnosed Reflux Noninvasively (BAD-BURN) in World Trade Center exposed firefighters: a case-control observational study protocol.

BACKGROUND: Particulate matter exposure (PM) is a cause of aerodigestive disease globally. The destruction of the World Trade Center (WTC) exposed first responders and inhabitants of New York City to WTC-PM and caused obstructive airways disease (OAD), gastroesophageal reflux disease (GERD) and Barrett's Esophagus (BE). GERD not only diminishes health-related quality of life but also gives rise to complications that extend beyond the scope of BE. GERD can incite or exacerbate allergies, sinusitis, bronchitis, and asthma. Disease features of the aerodigestive axis can overlap, often necessitating more invasive diagnostic testing and treatment modalities. This presents a need to develop novel non-invasive biomarkers of GERD, BE, airway hyperreactivity (AHR), treatment efficacy, and severity of symptoms. METHODS: Our observational case-cohort study will leverage the longitudinally phenotyped Fire Department of New York (FDNY)-WTC exposed cohort to identify Biomarkers of Airway Disease, Barrett's and Underdiagnosed Reflux Noninvasively (BAD-BURN). Our study population consists of n = 4,192 individuals from which we have randomly selected a sub-cohort control group (n = 837). We will then recruit subgroups of i. AHR only ii. GERD only iii. BE iv. GERD/BE and AHR overlap or v. No GERD or AHR, from the sub-cohort control group. We will then phenotype and examine non-invasive biomarkers of these subgroups to identify under-diagnosis and/or treatment efficacy. The findings may further contribute to the development of future biologically plausible therapies, ultimately enhance patient care and quality of life. DISCUSSION: Although many studies have suggested interdependence between airway and digestive diseases, the causative factors and specific mechanisms remain unclear. The detection of the disease is further complicated by the invasiveness of conventional GERD diagnosis procedures and the limited availability of disease-specific biomarkers. The management of reflux is important, as it directly increases risk of cancer and negatively impacts quality of life. Therefore, it is vital to develop novel noninvasive disease markers that can effectively phenotype, facilitate early diagnosis of premalignant disease and identify potential therapeutic targets to improve patient care. TRIAL REGISTRATION: Name of Primary Registry: "Biomarkers of Airway Disease, Barrett's and Underdiagnosed Reflux Noninvasively (BADBURN)". Trial Identifying Number: NCT05216133 . Date of Registration: January 31, 2022.

Test Characteristics of Emergency Medicine-Performed Point-of-Care Ultrasound for the Diagnosis of Acute Cholecystitis: A Systematic Review and Meta-analysis.

Acute cholecystitis accounts for up to 9% of hospital admissions for acute abdominal pain, and best practice entails early surgical management. Ultrasound is the standard modality used to confirm diagnosis. Our objective was to perform a systematic review and meta-analysis to determine the diagnostic accuracy of emergency physician-performed point-of-care ultrasound for the diagnosis of acute cholecystitis when compared with a reference standard of final diagnosis (informed by available surgical pathology, discharge diagnosis, and radiology-performed ultrasound). We completed a systematic review and meta-analysis, registered in PROSPERO, in adherence to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. We searched 7 databases as well as gray literature in the form of select conference abstracts from inception to February 8, 2023. Two independent reviewers completed study selection, data extraction, and risk of bias (QUADAS-2) assessment. Disagreements were resolved by consensus with a third reviewer. Data were extracted from eligible studies to create 2 × 2 tables for diagnostic accuracy meta-analysis. Hierarchical Summary Receiver Operating Characteristic models were constructed. Of 1855 titles/abstracts, 40 were selected for full-text review. Ten studies (n=2356) were included. Emergency physician-performed point-of-care ultrasound with final diagnosis as the reference standard (7 studies, n=1,772) had a pooled sensitivity of 70.9% (95% confidence interval [CI] 62.3 to 78.2), specificity of 94.4% (95% CI 88.2 to 97.5), positive likelihood ratio of 12.7 (5.8 to 27.5), and negative likelihood ratio of 0.31 (0.23 to 0.41) for the diagnosis of acute cholecystitis. Emergency physician-performed point-of-care ultrasound has high specificity and moderate sensitivity for the diagnosis of acute cholecystitis in patients with clinical suspicion. This review supports the use of emergency physician-performed point-of-care ultrasound to rule in a diagnosis of acute cholecystitis in the emergency department, which may help expedite definitive management.