Optical Torque Calculations and Measurements for DNA Torsional Studies.

The angular optical trap (AOT) is a powerful instrument for measuring the torsional and rotational properties of a biological molecule. Thus far, AOT studies of DNA torsional mechanics have been carried out using a high numerical aperture oil-immersion objective, which permits strong trapping, but inevitably introduces spherical aberrations due to the glass-aqueous interface. However, the impact of these aberrations on torque measurements is not fully understood experimentally, partly due to a lack of theoretical guidance. Here, we present a numerical platform based on the finite element method to calculate forces and torques on a trapped quartz cylinder. We have also developed a new experimental method to accurately determine the shift in the trapping position due to the spherical aberrations by using a DNA molecule as a distance ruler. We found that the calculated and measured focal shift ratios are in good agreement. We further determined how the angular trap stiffness depends on the trap height and the cylinder displacement from the trap center and found full agreement between predictions and measurements. As a further verification of the methodology, we showed that DNA torsional properties, which are intrinsic to DNA, could be determined robustly under different trap heights and cylinder displacements. Thus, this work has laid both a theoretical and experimental framework that can be readily extended to investigate the trapping forces and torques exerted on particles with arbitrary shapes and optical properties.

Vulnerability of Eastern Tropical Pacific chondrichthyan fish to climate change.

Climate change is an environmental emergency threatening species and ecosystems globally. Oceans have absorbed about 90% of anthropogenic heat and 20%-30% of the carbon emissions, resulting in ocean warming, acidification, deoxygenation, changes in ocean stratification and nutrient availability, and more severe extreme events. Given predictions of further changes, there is a critical need to understand how marine species will be affected. Here, we used an integrated risk assessment framework to evaluate the vulnerability of 132 chondrichthyans in the Eastern Tropical Pacific (ETP) to the impacts of climate change. Taking a precautionary view, we found that almost a quarter (23%) of the ETP chondrichthyan species evaluated were highly vulnerable to climate change, and much of the rest (76%) were moderately vulnerable. Most of the highly vulnerable species are batoids (77%), and a large proportion (90%) are coastal or pelagic species that use coastal habitats as nurseries. Six species of batoids were highly vulnerable in all three components of the assessment (exposure, sensitivity and adaptive capacity). This assessment indicates that coastal species, particularly those relying on inshore nursery areas are the most vulnerable to climate change. Ocean warming, in combination with acidification and potential deoxygenation, will likely have widespread effects on ETP chondrichthyan species, but coastal species may also contend with changes in freshwater inputs, salinity, and sea level rise. This climate-related vulnerability is compounded by other anthropogenic factors, such as overfishing and habitat degradation already occurring in the region. Mitigating the impacts of climate change on ETP chondrichthyans involves a range of approaches that include addressing habitat degradation, sustainability of exploitation, and species-specific actions may be required for species at higher risk. The assessment also highlighted the need to further understand climate change's impacts on key ETP habitats and processes and identified knowledge gaps on ETP chondrichthyan species.

El cambio climático es una emergencia medioambiental que amenaza a especies y ecosistemas en todo el mundo. Los océanos han absorbido alrededor del 90% del calor antropogénico y entre el 20% y el 30% de las emisiones de carbono, lo que ha provocado su calentamiento, acidificación, desoxigenación, cambios en la estratificación de los océanos y en la disponibilidad de nutrientes, así como fenómenos extremos más pronunciados. Dadas las predicciones de cambios, hay una importante necesidad de entender cómo las especies marinas se verán afectadas. En este estudio utilizamos una Evaluación Integrada de Riesgos para evaluar la vulnerabilidad de 132 condrictios del Pacífico Tropical Oriental (PTO) a los impactos del cambio climático. Adoptando un enfoque preventivo, estimamos que la vulnerabilidad general al cambio climático es Alta para casi una cuarta parte (23%) de las especies de condrictios del PTO evaluadas y Moderada para gran parte del resto (76%). La mayoría de las especies altamente vulnerables son batoideos (77%), y una gran proporción de éstas (90%) son especies costeras o especies pelágicas que utilizan los hábitats costeros como áreas de crianza. Seis especies de batoideos tuvieron una vulnerabilidad Alta en los tres componentes de la evaluación. Esta evaluación indica que las especies costeras, en particular las que dependen de áreas de crianza costeras, son las más vulnerables al cambio climático. Es probable que el calentamiento de los océanos, junto con la acidificación y la posible desoxigenación, tenga efectos generalizados sobre las especies de condrictios del PTO, pero las especies costeras se verán también afectadas por los cambios en los aportes de agua dulce, la salinidad y el aumento del nivel del mar. Esta vulnerabilidad relacionada con el clima se ve agravada por otros factores antropogénicos que ya se están produciendo en la región, como la sobrepesca y la degradación del hábitat. La mitigación de los impactos del cambio climático sobre los condrictios del PTO implica medidas que incluyan abordar la degradación del hábitat y la sostenibilidad de la explotación pesquera, y acciones para las especies de mayor riesgo son necesarias. Esta evaluación también destaca la necesidad de comprender mejor los impactos del cambio climático en los hábitats y procesos clave del PTO y las lagunas de conocimiento identificadas en relación con las especies de condrictios del PTO.

Hemispherectomy at The Hospital for Sick Children: expanded indications and lessons learned over 35 years.

OBJECTIVE: Functional hemispherectomy is an effective surgical intervention for select patients with drug-resistant epilepsy. The last several decades have seen dramatic evolutions in preoperative evaluation, surgical techniques, and postoperative care. Here, the authors present a retrospective review of the medical records of 146 children who underwent hemispherectomy between 1987 and 2022 at The Hospital for Sick Children, providing a unique overview of the evolution of the procedure and patient outcomes over 35 years. METHODS: The medical records of all children who underwent hemispherectomy at The Hospital for Sick Children between 1987 and 2022 were reviewed. Demographic information, preoperative clinical features, short-term and long-term seizure outcomes, and details regarding postoperative complications were recorded. RESULTS: The seizure outcomes of 146 children were analyzed. There were 68 females and 78 males with a mean age of 5.08 years, 123 of whom demonstrated seizure freedom (Engel class IA) in the short-term postoperative follow-up period and 89 in the long term. The effectiveness of hemispherectomy in achieving long-term seizure control has improved over time (ß = 0.06, p < 0.001). Factors associated with overall seizure freedom included younger age at the time of hemispherectomy and stroke as the etiology of seizures, as well as complete disconnection during the first surgery. Additionally, the etiologies of epilepsy for which hemispherectomy is performed have expanded over time, while complication rates have remained unchanged. CONCLUSIONS: Hemispherectomy is an increasingly effective treatment for certain cases of drug-resistant epilepsy. The etiologies of epilepsy for which hemispherectomy is performed are broadening, with no change in its safety profile. Seizure outcomes are better when the etiology of epilepsy is an ischemic injury, and the most common complication after the procedure is hydrocephalus. These findings reinforce the ongoing use of hemispherectomy as a safe and effective treatment option for certain individuals with drug-resistant epilepsy, support its application to a broader range of etiologies, and highlight areas of future investigation.

Inadequate Spinal Anesthesia in Lumbar Spine Surgery Is Related to Volume of the Thecal Sac.

BACKGROUND: Spinal anesthesia (SA) is used in lumbar surgery, but initial adequate analgesia fails in some patients. In these cases, spinal redosing or conversion to general endotracheal anesthesia is required, both of which are detrimental to the patient experience and surgical workflow. METHODS: We reviewed cases of lumbar surgery performed under SA from 2017-2021. We identified 12 cases of inadequate first dose and then selected 36 random patients as controls. We used a measurement tool to approximate the volume of the dural sac for each patient using T2-weighted sagittal magnetic resonance imaging sequences. RESULTS: Patients who had an inadequate first dose of anesthesia had a significantly larger dural sac volume, 22.8 ± 7.9 cm3 in the inadequate dose group and 17.4 ± 4.7 cm3 in controls (P = 0.043). The inadequate dose group was significantly younger, 54.2 ± 8.8 years in failed first dose and 66.4 ± 11.9 years in controls (P = 0.001). The groups did not differ by surgical procedure (P = 0.238), level (P = 0.353), American Society of Anesthesia score (P = 0.546), or comorbidities. CONCLUSIONS: We found that age, larger height, and dural sac volume are risk factors for an inadequate first dose of SA. The availability of spinal magnetic resonance imaging in patients undergoing spine surgery allows the preoperative measurement of their thecal sac size. In the future, these data may be used to personalize spinal anesthesia dosing on the basis of individual anatomic variables and potentially reduce the incidence of failed spinal anesthesia in spine surgery.

Muscle fibrosis, NF-κB, and TGF-ß are differentially altered in two models of paralysis (Botox vs. Neurectomy).

OBJECTIVE: Volumetric muscle loss (VML) results in intramuscular axotomy, denervating muscle and leading to paralysis and loss of muscle function. Once the nerve is damaged, paralyzed skeletal muscle will atrophy and accumulate non-contractile connective tissue. The objective of this study was to determine differences in connective tissue, atrophy, and inflammatory signaling between two paralysis models, botulinum toxin (Botox), which blocks acetylcholine transmission while keeping nerves intact, and neurectomy, which eliminates all nerve to muscle signaling. APPROACH: Twenty-eight male Sprague Dawley rats were randomized and received either a sciatic-femoral neurectomy (SFN), Botox-induced muscle paralysis of the proximal femur muscles, quadriceps femoris, hamstrings, and calf muscles (BTX), or sham. Muscle force was measured 52 days post-surgery, and samples were collected for histology, protein, and mRNA assays. RESULTS: SNF and BTX decreased twitch and tetanic force, decreased fiber size by two-fold, and increased myogenic expression compared to controls. SFN increased levels of all major ECM proteins correlating with fibrosis (e.g. laminin, fibronectin, and collagen type(s) I, III, VI). SFN also increased pro-fibrotic and pro-inflammatory mRNA compared to BTX and controls. INNOVATION: SFN and BTX were similar in gross morphology and functional deficiencies. However, SFN exhibited a higher amount of fibrosis in histological sections and immunoblotting. The present study shows evidence that nerve signaling changes NF-κB and TGF-ß signaling, warranting future studies to determine the mechanisms involved. CONCLUSION: These data indicate that nerve signaling may influence fibrogenesis following denervation, but the mechanisms involved may differ as a function of the method of paralysis.

The Study of the Epidemiology of Pediatric Hypertension Registry (SUPERHERO): Rationale and Methods.

Despite increasing prevalence of hypertension in youth and high adult cardiovascular mortality rates, the long-term consequences of youth-onset hypertension remain unknown. This is due to limitations of prior research such as small sample sizes, reliance on manual record review, and limited analytic methods that did not address major biases. The Study of the Epidemiology of Pediatric Hypertension (SUPERHERO) is a multisite retrospective Registry of youth evaluated by subspecialists for hypertension disorders. Sites obtain harmonized electronic health record data using standardized biomedical informatics scripts validated with randomized manual record review. Inclusion criteria are index visit for International Classification of Diseases Diagnostic Codes, 10th Revision (ICD-10 code)-defined hypertension disorder ≥January 1, 2015 and age <19 years. We exclude patients with ICD-10 code-defined pregnancy, kidney failure on dialysis, or kidney transplantation. Data include demographics, anthropomorphics, U.S. Census Bureau tract, histories, blood pressure, ICD-10 codes, medications, laboratory and imaging results, and ambulatory blood pressure. SUPERHERO leverages expertise in epidemiology, statistics, clinical care, and biomedical informatics to create the largest and most diverse registry of youth with newly diagnosed hypertension disorders. SUPERHERO's goals are to (i) reduce CVD burden across the life course and (ii) establish gold-standard biomedical informatics methods for youth with hypertension disorders.

Incidence and remission of post-surgical cystoid macular edema following cataract surgery in eyes with intraocular inflammation.

PURPOSE: To evaluate the incidence, remission and relapse of post-surgical cystoid macular edema (PCME) following cataract surgery in inflammatory eye disease. METHODS: A total of 1859 eyes that had no visually significant macular edema prior to cataract surgery while under tertiary uveitis management were included. Standardized retrospective chart review was used to gather clinical data. Univariable and multivariable logistic regression models with adjustment for inter-eye correlations were performed. RESULTS: PCME causing VA 20/50 or worse was reported in 286 eyes (15%) within 6 months of surgery. Adults age 18-64 years as compared to children (adjusted Odds ratio (aOR) 2.42, for ages 18-44 and aOR 1.93 for ages 45-64, overall p = 0.02); concurrent use of systemic immunosuppression (conventional aOR 1.53 and biologics aOR 2.68, overall p =0.0095); pre-operative VA 20/50 or worse (overall p <0.0001); cataract surgery performed before 2000 (overall p=0.03) and PMCE in fellow eye (aOR 3.04, p=0.0004) were associated with development of PCME within 6 months of cataract surgery. PCME resolution was seen in 81% of eyes at 12 months and 91% of eyes at 24 months. CME relapse was seen in 12% eyes at 12 months and 19% eyes at 24 months. CONCLUSIONS: PCME occurs frequently in uveitic eyes undergoing cataract surgery, however, most resolve within a year. CME recurrences likely are due to the underlying disease process and not relapses of PCME.

Genetic Implication of Prenatal GABAergic and Cholinergic Neuron Development in Susceptibility to Schizophrenia.

BACKGROUND: The ganglionic eminences (GE) are fetal-specific structures that give rise to gamma-aminobutyric acid (GABA)- and acetylcholine-releasing neurons of the forebrain. Given the evidence for GABAergic, cholinergic, and neurodevelopmental disturbances in schizophrenia, we tested the potential involvement of GE neuron development in mediating genetic risk for the condition. STUDY DESIGN: We combined data from a recent large-scale genome-wide association study of schizophrenia with single-cell RNA sequencing data from the human GE to test the enrichment of schizophrenia risk variation in genes with high expression specificity for developing GE cell populations. We additionally performed the single nuclei Assay for Transposase-Accessible Chromatin with Sequencing (snATAC-Seq) to map potential regulatory genomic regions operating in individual cell populations of the human GE, using these to test for enrichment of schizophrenia common genetic variant liability and to functionally annotate non-coding variants-associated with the disorder. STUDY RESULTS: Schizophrenia common variant liability was enriched in genes with high expression specificity for developing neuron populations that are predicted to form dopamine D1 and D2 receptor-expressing GABAergic medium spiny neurons of the striatum, cortical somatostatin-positive GABAergic interneurons, calretinin-positive GABAergic neurons, and cholinergic neurons. Consistent with these findings, schizophrenia genetic risk was concentrated in predicted regulatory genomic sequence mapped in developing neuronal populations of the GE. CONCLUSIONS: Our study implicates prenatal development of specific populations of GABAergic and cholinergic neurons in later susceptibility to schizophrenia, and provides a map of predicted regulatory genomic elements operating in cells of the GE.

Confinement and magnetic-field effect on chiral ferroelectric nematic liquid crystals in Grandjean-Cano wedge cells.

We explore the structure and magnetic-field response of edge dislocations in Grandjean-Cano wedge cells filled with chiral mixtures of the ferroelectric nematic mesogen DIO. Upon cooling, the ordering changes from paraelectric in the cholesteric phase N^{*} to antiferroelectric in the smectic SmZ_{A}^{*} and to ferroelectric in the cholesteric N_{F}^{*}. Dislocations of the Burgers vector b equal to the helicoidal pitch P are stable in all three phases, while dislocations with b=P/2 exist only in the N^{*} and SmZ_{A}^{*}. The b=P/2 dislocations split into pairs of τ^{-1/2}λ^{+1/2} disclinations, while the thick dislocations b=P are pairs of nonsingular λ^{-1/2}λ^{+1/2} disclinations. The polar order makes the τ^{-1/2} disclinations unstable in the N_{F}^{*} phase, as they should be connected to singular walls in the polarization field. We propose a model of transformation of the composite τ^{-1/2} line-wall defect into a nonsingular λ^{-1/2} disclination, which is paired up with a λ^{+1/2} line to form a b=P dislocation. The SmZ_{A}^{*} behavior in the in-plane magnetic field is different from that of the N_{F}^{*} and N^{*}: the dislocations show no zigzag instability, and the pitch remains unchanged in the magnetic fields up to 1 T. The behavior is associated with the finite compressibility of smectic layers.

A 19-year longitudinal assessment of gyromitrin-containing (Gyromitra spp.) mushroom poisonings in Michigan.

Mushroom poisonings are common in the United States. Gyromitrin (acetaldehyde N-methyl-N-formylhydrazone) is a clinically significant mycotoxin primarily associated with the lorchel (i.e. the false morel) Gyromitra esculenta. Resemblance between 'true and false morels' has resulted in misidentification of Gyromitra spp. as edible and sought after Morchella spp., resulting in toxicity. Despite literature evidence outlining toxic sequalae, Gyromitra spp. mushrooms are commonly consumed and prepared for culinary purposes. Classic clinical teachings emphasize significant neurotoxicity, including seizures, associated with ingestion of gyromitrin-containing mushrooms, stemming from gyromitrin's terminal metabolite monomethylhydrazine. We performed a longitudinal descriptive review of the clinical toxicity associated with ingestion of mushroom species known or suspected to contain gyromitrin in cases reported to the Michigan Poison & Drug Information Center between January 1, 2002, to December 31, 2020. Our 19-year descriptive case series of gyromitrin-containing mushroom ingestions reported to our Center demonstrated a preponderance of gastrointestinal signs and symptoms, including hepatotoxicity. Of 118 identified cases, 108 (91.5%) of the reported ingestions involved Gyromitra esculenta. The most frequent clinical findings associated with symptomatic ingestions (n= 83) were the aforementioned gastrointestinal symptoms (n=62; 74.7%). Neurological symptoms were less frequent (n=22, 26.5%) while hepatotoxicity occurred in fewer patients (n=14; 16.9%). Of symptomatic patients, most were treated with symptomatic and supportive care (n=58; 70%). Pyridoxine was used in a total of seven patients (n=7; 8.4%) with either hepatotoxicity or neurotoxicity. Medical outcomes ranged from minor to major, with no reported deaths. Patient presentations (i.e. GI vs. neurotoxic symptoms) following ingestion of gyromitrin-containing mushrooms may be highly variable and multifactorial, owing to differences in dose ingested, geographical distribution, genetic variability of both patient and mushroom species, and species-specific differences in toxin composition. Future research warrants species-level identification of ingested gyromitrin-containing mushrooms and investigating the contribution of genetic polymorphisms to differences in clinical toxidromes.

Risk of Recurrence in Acute Anterior Uveitis.

PURPOSE: To examine the frequency of recurrence and identify risk factors for recurrence in patients with acute anterior uveitis (AAU). DESIGN: Retrospective cohort study from a single tertiary ophthalmic clinical centre. PARTICIPANTS: All subjects with AAU identified from a database of Inflammatory Eye Disease presenting to Te Whatu Ora (Auckland, New Zealand) between 2008 and 2021. METHODS: Data was collected retrospectively from chart review and electronic patient records for all patients during the study period. Rates of recurrence were reported using Kaplan Meier estimator. Multivariate analysis of risk factors for recurrence were calculated using a marginal Cox regression model. MAIN OUTCOME MEASURES: The primary outcome measure was disease recurrence. Secondary outcome measure was moderate vision loss (≤20/50). RESULTS: 2763 eyes of 2092 subjects with AAU were studied, with a median follow up time of 8.9 years, and a total follow up of 19,794.9 eye-years. Recurrence occurred in the ipsilateral eye in 1258 eyes (45.5%) and in the contralateral eye in 522 eyes (27.3%). Rates of ipsilateral recurrence over ten years were 38.1% for idiopathic disease, 43.2% for HLAB27/inflammatory arthritis, and 44.9% for viral uveitis. On multivariate analysis the following were associated with increased risk of ipsilateral recurrence: older age (p<0.001); Maori ethnicity (p=0.006); Asian ethnicity (p<0.001); HLA-B27/inflammatory arthritis (p<0.001); viral uveitis (p=0.018). There was no association with gender, smoking, bilateral disease, or hypertensive uveitis. Rates of contralateral eye involvement were significantly lower than ipsilateral eye recurrence. Contralateral recurrence at ten years was 15.2% in idiopathic uveitis, 37.6% in HLAB27/inflammatory arthritis, and 2.0% in viral uveitis. Risk factors identified for contralateral eye involvement were Maori ethnicity (p=0.003), Pasifika (Pacific Islanders) ethnicity (p=0.021), HLAB27/inflammatory arthritis (p<0.001). Moderate vision loss (≤20/50) was present in 411 eyes (14.9%) at final follow up and was more common if time to first recurrence was shorter (p<0.001). CONCLUSIONS: Approximately half of patients with AAU will develop recurrence in the ipsilateral eye and a quarter will have recurrence in the contralateral eye. Patients with viral disease have the highest risk of ipsilateral recurrence and lowest risk of contralateral recurrence. Patients with risk factors for recurrence should be managed and counselled appropriately to minimise the risk of visual loss and complications of uveitis.

Optical Torque Calculations and Measurements for DNA Torsional Studies.

The angular optical trap (AOT) is a powerful instrument for measuring the torsional and rotational properties of a biological molecule. Thus far, AOT studies of DNA torsional mechanics have been carried out using a high numerical aperture oil-immersion objective, which permits strong trapping, but inevitably introduces spherical aberrations due to the glass-aqueous interface. However, the impact of these aberrations on torque measurements is not fully understood experimentally, partly due to a lack of theoretical guidance. Here, we present a numerical platform based on the finite element method to calculate forces and torques on a trapped quartz cylinder. We have also developed a new experimental method to accurately determine the shift in the trapping position due to the spherical aberrations by using a DNA molecule as a distance ruler. We found that the calculated and measured focal shift ratios are in good agreement. We further determined how the angular trap stiffness depends on the trap height and the cylinder displacement from the trap center and found full agreement between predictions and measurements. As further verification of the methodology, we showed that DNA torsional properties, which are intrinsic to DNA, could be determined robustly under different trap heights and cylinder displacements. Thus, this work has laid both a theoretical and experimental framework that can be readily extended to investigate the trapping forces and torques exerted on particles with arbitrary shapes and optical properties. SIGNIFICANCE: We developed a simulation platform based on the finite element method for force and torque calculation for particles in an angular optical trap (AOT), with considerations of tightly focused Gaussian beam, spherical aberrations, and optically anisotropic particles. Experimental measurements of focal shift ratio, force, and torque under multiple conditions were in good agreement with predictions from the simulations. We also demonstrated that intrinsic DNA torsional properties can be robustly measured under different AOT measurement conditions, strongly validating our simulations and calibrations. Our platform can facilitate trapping particle design for single-molecule assays using the AOT.

Effect of grain size variation on strontium sorption to heterogeneous aquifer sediments.

Strontium-90 (90Sr) is a major contaminant at nuclear legacy sites. The mobility of 90Sr is primarily governed by sorption reactions with sediments controlled by high surface area phases such as clay and iron oxides. Sr2+ adsorption was investigated in heterogeneous unconsolidated aquifer sediments, analogous to those underlying the UK Sellafield nuclear site, with grainsizes ranging from gravels to clays. Batch sorption tests showed that a linear Kd adsorption model was applicable to all grainsize fractions up to equilibrium [Sr] of 0.28 mmol L-1. Sr2+ sorption values (Kd; Langmuir qmax) correlated well with bulk sediment properties such as cation exchange capacity and surface area. Electron microscopy showed that heterogeneous sediments contained porous sandstone clasts with clay minerals (i.e. chlorite) providing an additional adsorption capacity. Therefore, gravel corrections that assumed that the > 2 mm fractions are inert were not appropriate and underestimated Kd(bulk) adsorption coefficients. However, Kd (<2 mm) values measured from sieved sediment fractions, were effectively adjusted to within error of Kd (bulk) using a surface area dependant gravel correction based on particle size distribution data. Amphoteric pH dependent Sr2+ sorption behaviour observed in batch experiments was consistent with cation exchange modelling between pH 2-7 derived from the measured cation exchange capacities. Above pH 7 model fits were improved by invoking a coupled cation exchange/surface complexation which allowed for addition sorption to iron oxide phases. The overall trends in Sr2+ sorption (at pH 6.5-7) produced by increasing solution ionic strength was also reproduced in cation exchange models. Overall, the results showed that Sr2+ sorption to heterogeneous sediment units could be estimated from Kd (<2 mm) data using appropriate gravel corrections, and effectively modelled using coupled cation exchange and surface complexation processes.

Do serial troponins predict the need for cardiac evaluation in trauma patients after ground-level fall?

Purpose: Troponin T levels are routinely checked in trauma patients after experiencing a ground-level fall to identify potential cardiac causes of syncope. An elevated initial troponin prompts serial testing until the level peaks. However, the high sensitivity of the test may lead to repeat testing that is of little clinical value. Here, we examine the role of serial troponins in predicting the need for further cardiac workup in trauma patients after sustaining a fall. Methods: Retrospective review of all adult trauma activations for ground-level fall from January 1, 2021 to December 31, 2021 in patients who were hemodynamically and neurologically normal at presentation. Outcomes evaluated included need for cardiology consult, admission to cardiology service, outpatient cardiology follow-up, cardiology intervention and in-hospital mortality. Results: There were 1555 trauma activations for ground-level fall in the study period. The cohort included 560 patients evaluated for a possible syncopal fall, hemodynamically stable, Glasgow Coma Scale score of 15, and with a troponin drawn at presentation. The initial median troponin was 20 ng/L (13-37). Second troponin values were drawn on 58% (median 33 ng/L (22-52)), with 42% of patients having an increase from first to second test. 29% of patients had a third troponin drawn (median 42 ng/L (26-67)). The initial troponin value was significantly associated with undergoing a subsequent echo (p=0.01), cardiology consult (p<0.01), admission for cardiac evaluation (p<0.01), cardiology follow-up (p<0.01), and in-hospital mortality (p=0.01); the initial troponin was not associated with cardiac intervention (p=0.91). An increase from the first to second troponin was not associated with any of outcomes of interest. Analysis was done with cut-off values of 30 ng/L, 50 ng/L, 70 ng/L, and 90 ng/L; a troponin T threshold of 19 ng/L was significant for cardiology consult (p=0.01) and cardiology follow-up (p=0.04). When the threshold was increased to 50 ng/L, it was also significant for admission for cardiac issue (p<0.01). When the threshold was increased to 90 ng/L, it was significant for the same three outcomes and in-hospital mortality (p=0.04). Conclusion: The initial serum troponin has clinical value in identifying underlying cardiac disease in patients who present after ground-level fall; however, that serial testing is likely of little value. Further, using a cut-off of >50 ng/L as a threshold for further clinical evaluation would improve the utility of the test and likely reduce unnecessary hospital stays and costs for otherwise healthy patients. Level of evidence: Level III.

Measuring complexity for hierarchical models using effective degrees of freedom.

Hierarchical models can express ecological dynamics using a combination of fixed and random effects, and measurement of their complexity (effective degrees of freedom, EDF) requires estimating how much random effects are shrunk toward a shared mean. Estimating EDF is helpful to (1) penalize complexity during model selection and (2) to improve understanding of model behavior. I applied the conditional Akaike Information Criterion (cAIC) to estimate EDF from the finite-difference approximation to the gradient of model predictions with respect to each datum. I confirmed that this has similar behavior to widely used Bayesian criteria, and I illustrated ecological applications using three case studies. The first compared model parsimony with or without time-varying parameters when predicting density-dependent survival, where cAIC favors time-varying demographic parameters more than conventional Akaike Information Criterion. The second estimates EDF in a phylogenetic structural equation model, and identifies a larger EDF when predicting longevity than mortality rates in fishes. The third compares EDF for a species distribution model fitted for 20 bird species and identifies those species requiring more model complexity. These highlight the ecological and statistical insight from comparing EDF among experimental units, models, and data partitions, using an approach that can be broadly adopted for nonlinear ecological models.

N-Acetyltransferase Metabolism and DNA Damage Following Exposure to 4,4'-Oxydianiline in Human Bronchial Epithelial Cells.

Waterpipe smoking is increasingly popular and understanding how chemicals found in hookah smoke may be harmful to human bronchial epithelial cells is of great importance. 4,4'-Oxydianiline (ODA), is an aromatic amine which is present at comparatively high levels in hookah smoke. The metabolism and the subsequent toxicity of ODA to human bronchial epithelial cells remains unknown. Given that ODA is an aromatic amine, we hypothesized that ODA is N-acetylated and induces DNA damage following exposure to immortalized human bronchial epithelial cells (BEP2D cells). We measured the N-acetylation of ODA to mono-acetyl-ODA and the N-acetylation of mono-acetyl-ODA to diacetyl-ODA by BEP2D cells following separation and quantitation by high performance liquid chromatography. For ODA, the apparent KM in cells was 12.4 ± 3.7µM with a Vmax of 0.69 ± 0.03 nmol/min/106 cells, while for mono-acetyl-ODA, the apparent KM was 111.2 ± 48.3µM with a Vmax of 17.8 ± 5.7 nmol/min/106 cells ODA exposure for 24h resulted in DNA damage to BEP2D cells following concentrations as low as 0.1µM as measured by yH2Ax protein expression These results demonstrate that ODA, the most prevalent aromatic amine identified in hookah smoke, is N-acetylated and induces DNA damage in human bronchial epithelial cells.

Celebrating 10 Years of the HIMSS-SIIM Enterprise Imaging Community and Enterprise Imaging Informatics.

In response to the growing recognition of enterprise imaging as a critical component of healthcare's digital transformation, in 2014, the Healthcare Information and Management Systems Society (HIMSS) and the Society for Imaging Informatics in Medicine (SIIM) signed a Memorandum of Understanding to form the HIMSS-SIIM Enterprise Imaging Community (HSEIC). At the time of the agreement, the two organizations decided to collaborate to lead enterprise imaging development, advancement, and adoption. This paper celebrates the past 10 years of the HSEIC's thought leadership, industry partnerships, and impact while also looking ahead to identify enterprise imaging challenges to solve in the next decade.

On Persons, Populations, and Causal Mechanisms Some Critical Reflections on Lundh (2023).

While agreeing with Lundh (2023) on many of his major points, this article also questions the notion of a 'population psychology.' It is argued that the knowledge produced in population-level studies, whether correlational, experimental, or mixed, is inherently demographic in nature. Concerning individual-level studies, agreement with Lundh (2023) is expressed concerning the need to distinguish between a conception of individuals as mere depositories of neurophysiological mechanisms on the one hand, and as active, purposeful agents on the other. It is suggested that the conceptual framework called 'critical personalism' would well serve a scientific psychology committed to the latter view.

A cost-effectiveness analysis of early detection and bundled treatment of postpartum hemorrhage alongside the E-MOTIVE trial.

Timely detection and treatment of postpartum hemorrhage (PPH) are crucial to prevent complications or death. A calibrated blood-collection drape can help provide objective, accurate and early diagnosis of PPH, and a treatment bundle can address delays or inconsistencies in the use of effective interventions. Here we conducted an economic evaluation alongside the E-MOTIVE trial, an international, parallel cluster-randomized trial with a baseline control phase involving 210,132 women undergoing vaginal delivery across 78 secondary-level hospitals in Kenya, Nigeria, South Africa and Tanzania. We aimed to assess the cost-effectiveness of the E-MOTIVE intervention, which included a calibrated blood-collection drape for early detection of PPH and a bundle of first-response treatments (uterine massage, oxytocic drugs, tranexamic acid, intravenous fluids, examination and escalation), compared with usual care. We used multilevel modeling to estimate incremental cost-effectiveness ratios from the perspective of the public healthcare system for outcomes of cost per severe PPH (blood loss ≥1,000 ml) avoided and cost per disability-adjusted life-year averted. Our findings suggest that the use of a calibrated blood-collection drape for early detection of PPH and bundled first-response treatment is cost-effective and should be perceived by decision-makers as a worthwhile use of healthcare budgets. ClinicalTrials.gov identifier: NCT04341662 .

A real-time antibody-dependent cellular phagocytosis assay by live cell imaging.

Antibody-dependent cellular phagocytosis (ADCP) is a cellular process by which antibody-opsonized targets (pathogens or cells) activate the Fc receptors on the surface of phagocytes to induce phagocytosis, resulting in internalization and degradation of pathogens or target cells through phagosome acidification. Besides NK cells-mediated antibody-dependent cellular cytotoxicity (ADCC), tumor-infiltrated monocytes and macrophages can directly kill tumor cells in the presence of tumor antigen-specific antibodies through ADCP, representing another attractive strategy for cancer immunotherapy. Even though several methods have been developed to measure ADCP, an automated and high-throughput quantitative assay should offer highly desirable advantages for drug discovery. In this study we established a new ADCP assay to identify therapeutical monoclonal antibodies (mAbs) that facilitate macrophages phagocytosis of live target cells. We used Incucyte, an imaging system for live cell analysis. By labeling the live target cells with a pH sensitive dye (pHrodo), we successfully monitored the ADCP in real time. We demonstrated that our image-based assay is robust and quantitative, suitable for screening and characterization of therapeutical mAbs that directly kill target cells through ADCP. Furthermore, we found different subtypes of macrophages have distinct ADCP activities using both mouse and human primary macrophages differentiated in vitro. By studying various mAbs with mutations in their Fc regions using our assay, we showed that the variants with increased binding to Fc gamma receptors (FcγRs) have enhanced ADCP activities.