bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Yield of Computed Tomography of the Head Among Patients Presenting With Syncope: A Systematic Review
Authors: Viau J. Alexander , Chaudry Hina , Hannigan Ailish , Boutet Mish , Mukarram Muhammad , Thiruganasambandamoorthy Venkatesh 
Published: April 2019

AbstractBackgroundOveruse of head computed tomography (CT) for syncope has been reported. However, there is no literature synthesis on this overuse. We undertook a systematic review to determine the use and yield of head CT and risk factors for serious intracranial conditions among syncope patients.MethodsWe searched Embase, Medline, and Cochrane databases from inception until June 2017. Studies including adult syncope patients with part or all of patients undergoing CT head were included. We excluded case reports, reviews, letters, and pediatric studies. Two independent reviewers screened the articles and collected data on CT head use, diagnostic yield (proportion with acute hemorrhage, tumors or infarct), and risk of bias. We report pooled percentages, I2, and Cochran's Q‐test.ResultsSeventeen articles with 3,361 syncope patients were included. In eight ED studies (n = 1,669), 54.4% (95% confidence interval [CI] = 34.9%–73.2%) received head CT with a 3.8% (95% CI = 2.6%–5.1%) diagnostic yield and considerable heterogeneity. In six in‐hospital studies (n = 1,289), 44.8% (95% CI = 26.4%–64.1%) received head CT with a 1.2% (95% CI = 0.5%–2.2%) yield and no heterogeneity. In two articles, all patients had CT (yield 2.3%) and the third enrolled patients ≥ 65 years old (yield 7.7%). Abnormal neurologic findings, age ≥ 65 years, trauma, warfarin use, and seizure/stroke history were identified as risk factors. The quality of all articles referenced was strong.ConclusionMore than half of patients with syncope underwent CT head with a diagnostic yield of 1.1% to 3.8%. A future large prospective study is needed to develop a robust risk tool.
Ethanol Exposure Increases miR‐140 in Extracellular Vesicles: Implications for Fetal Neural Stem Cell Proliferation and Maturation
Authors: Tseng Alexander M. , Chung Dae D. , Pinson Marisa R. , Salem Nihal A. , Eaves Sarah E. , Miranda Rajesh C. 
Published: April 2019

BackgroundNeural stem cells (NSCs) generate most of the neurons of the adult brain in humans, during the mid‐first through second‐trimester period. This critical neurogenic window is particularly vulnerable to prenatal alcohol exposure, which can result in diminished brain growth. Previous studies showed that ethanol (EtOH) exposure does not kill NSCs, but, rather, results in their depletion by influencing cell cycle kinetics and promoting aberrant maturation, in part, by altering NSC expression of key neurogenic miRNAs. NSCs reside in a complex microenvironment rich in extracellular vesicles, shown to traffic miRNA cargo between cells.MethodsWe profiled the miRNA content of extracellular vesicles from control and EtOH‐exposed ex vivo neurosphere cultures of fetal NSCs. We subsequently examined the effects of one EtOH‐sensitive miRNA, miR‐140‐3p, on NSC growth, survival, and maturation.ResultsEtOH exposure significantly elevates levels of a subset of miRNAs in secreted extracellular vesicles. Overexpression of one of these elevated miRNAs, miR‐140‐3p, and its passenger strand relative, miR‐140‐5p, significantly increased the proportion of S‐phase cells while decreasing the proportion of G0/G1 cells compared to controls. In contrast, while miR‐140‐3p knockdown had minimal effects on the proportion of cells in each phase of the cell cycle, knockdown of miR‐140‐5p significantly decreased the proportion of cells in G2/M phase. Furthermore, miR‐140‐3p overexpression, during mitogen‐withdrawal–induced NSC differentiation, favors astroglial maturation at the expense of neural and oligodendrocyte differentiation.ConclusionsCollectively, the dysregulated miRNA content of extracellular vesicles following EtOH exposure may result in aberrant neural progenitor cell growth and maturation, explaining brain growth deficits associated with prenatal alcohol exposure.
Evaluating the correlation between adrenal gland dimensions and aortic diameter in healthy dogs
Authors: Ghavidel Mahshid , Mirshahi Ali , Azizzadeh Mohammad , Khoshnegah Javad 
Published: April 2019

AbstractIn the present study, the relationship of normal adrenal dimensions with weight, aortic diameter, age and sex was evaluated. Moreover, a formula for estimating the normal dimensions of adrenal gland was provided. Thirty‐two intact adult dogs that were considered healthy based on history, physical examination, routine blood works and specific adrenal tests as well as absence of any abnormal ultrasonographic findings were included. Adrenal glands and abdominal aorta were imaged in the sagittal plane by ultrasound. Length, maximal height of the cranial and caudal poles, area and circumference of the left and right adrenal glands and also the internal diameter of the abdominal aorta were measured. Analysis showed that there is a positive correlation between the adrenal gland dimensions and weight and aortic diameter. The ratio of adrenal gland dimensions and the aortic diameter was calculated, but this ratio showed a great amount of variability in tandem with a significant correlation to the weight; Meaning that the ratio of the adrenal gland dimensions to the aortic diameter was not a reliable index for evaluating the size of the normal adrenal gland in animals with different weights. Therefore, we used the weight along with adrenal measurements in a linear regression model, and then, we were able to estimate the adrenal gland dimensions in different weights. Knowing the relationship of normal adrenal dimensions with the indices such as weight, age, sex and diameter of abdominal aorta can help the clinicians to diagnose the adrenal gland diseases.
Erythrocytes restrict microvesicle‐induced production of reactive oxygen species by polymorphonuclear leukocytes
Authors: Winberg Line Kjær , Rasmussen Niclas Stefan , Nielsen Claus Henrik , Jacobsen Søren 
Published: April 2019

Microvesicles (MVs) are extracellular vesicles released by several cell types upon activation or apoptosis. MVs have the potential to activate complement, which has been suggested to mediate their clearance. However, it is not clear how complement‐opsonized MVs are prevented from activating circulating polymorphonuclear leukocytes (PMNs) with release of reactive oxygen species (ROS) and potential damage of endothelium and other bystander cells as consequence. We hypothesized that binding of opsonized MVs to erythrocytes (Es) attenuates MV‐induced PMN activation. To test this, normal PMNs were exposed to MVs in the presence and absence of Es from allogenic healthy donors. As analyzed by flow cytometry, the presence of Es restricted the PMN binding of MVs by about 85% (p = 0.002) and mediated a 60–70% inhibition of the PMN production of the ROS H2O2, induced by MVs, when lipopolysaccharide was used as a primer (p = 0.002). The competitive binding of MVs to Es was partly dependent on complement, since EDTA inhibited MV binding to Es by 75%. These data suggest that Es, through competitive binding, may restrict MV‐induced activation of circulating PMNs and thereby serve a role as a regulator of PMN activation.
Flexible Industrial Work in the European Periphery: Factory Regimes and Changing Working‐Class Cultures in the Spanish Steel Industry
Authors: Gonzalez‐Polledo Elena , Sabaté Muriel Irene 
Published: April 2019

AbstractThis article explores how two steel industry firms operating in northern Spain have adapted to neoliberalism and globalization. Despite their geographical proximity, the comparison between their different trajectories, production, and ownership profiles highlights how their distinct factory regimes, while becoming entangled in global market dynamics, have allowed the emergence of contrasting definitions of workers’ identities, labor politics, and livelihood strategies, raising questions concerning (1) processes of distribution of privileges, skills, and knowledge among the workforce, and (2) the shaping of social relations, values, and meanings that result in the formation of particular factory regimes. The unequal position of steelmaking in regional economies, and the effects of economic policies that framed social relations in each firm, evince important differences between them, including contrasting expressions of resistance, discipline, and sociality on the shop floor. Our comparison considers how particular factory regimes bring forward different prospects as these firms face further industrial transformation, restructuring, and an increasingly uncertain future.
Bayesian Modeling of Air Pollution Extremes Using Nested Multivariate Max-Stable Processes
Authors: Vettori Sabrina , Huser Raphaël , Genton Marc G. 
Published: April 2019

Abstract
Capturing the potentially strong dependence among the peak concentrations of multiple air pollutants across a spatial region is crucial for assessing the related public health risks. In order to investigate the multivariate spatial dependence properties of air pollution extremes, we introduce a new class of multivariate max-stable processes. Our proposed model admits a hierarchical tree-based formulation, in which the data are conditionally independent given some latent nested positive stable random factors. The hierarchical structure facilitates Bayesian inference and offers a convenient and interpretable characterization. We fit this nested multivariate max-stable model to the maxima of air pollution concentrations and temperatures recorded at a number of sites in the Los Angeles area, showing that the proposed model succeeds in capturing their complex tail dependence structure.
Scalable Estimation and Regularization for the Logistic Normal Multinomial Model
Authors: Zhang Jingru , Lin Wei 
Published: April 2019

AbstractClustered multinomial data are prevalent in a variety of applications such as microbiome studies, where metagenomic sequencing data are summarized as multinomial counts for a large number of bacterial taxa per subject. Count normalization with ad hoc zero adjustment tends to result in poor estimates of abundances for taxa with zero or small counts. To account for heterogeneity and overdispersion in such data, we suggest using the logistic normal multinomial (LNM) model with an arbitrary correlation structure to simultaneously estimate the taxa compositions by borrowing information across subjects. We overcome the computational difficulties in high dimensions by developing a stochastic approximation EM algorithm with Hamiltonian Monte Carlo sampling for scalable parameter estimation in the LNM model. The ill-conditioning problem due to unstructured covariance is further mitigated by a covariance-regularized estimator with a condition number constraint. The advantages of the proposed methods are illustrated through simulations and an application to human gut microbiome data.
Variance Component Tests of Multivariate Mediation Effects Under Composite Null Hypotheses
Authors: Huang Yen-Tsung 
Published: April 2019

AbstractMediation effects of multiple mediators are determined by two associations: one between an exposure and mediators ( -) and the other between the mediators and an outcome conditional on the exposure ( -). The test for mediation effects is conducted under a composite null hypothesis, that is, either one of the - and - associations is zero or both are zeros. Without accounting for the composite null, the type 1 error rate within a study containing a large number of multimediator tests may be much less than the expected. We propose a novel test to address the issue. For each mediation test , , we examine the - and - associations using two separate variance component tests. Assuming a zero-mean working distribution with a common variance for the element-wise - (and -) associations, score tests for the variance components are constructed. We transform the test statistics into two normally distributed statistics under the null. Using a recently developed result, we conduct hypothesis tests accounting for the composite null hypothesis by adjusting for the variances of the normally distributed statistics for the - and - associations. Advantages of the proposed test over other methods are illustrated in simulation studies and a data application where we analyze lung cancer data from The Cancer Genome Atlas to investigate the smoking effect on gene expression through DNA methylation in 15 114 genes.
Design, synthesis, and biological evaluation of lipophilically modified bisphenol Z derivatives
Authors: Stitzlein Lea M. , Stang Christopher R. T. , Inbody Laura R. , Rao P. S. S. , Schneider Ryan A. , Dudley Richard W. 
Published: April 2019

AbstractIn the present study, a small library of bisphenol Z (BPZ) derivatives was synthesized and investigated for anti‐proliferative effects in cultured breast and glioblastoma cell lines. Synthesized BPZ derivatives varied in molecular size, polarity, and lipophilicity. Of the 8 derivatives tested, compounds 4 and 6, both of which displayed the highest degree of lipophilicity, were most active at inducing cell death as determined by the XTT assay. Cell membranes were interrogated using trypan blue staining and were shown to remain intact during treatments with 4 and 6. Activation of caspase enzymes (3 and/or 7) was noted to occur following treatment with compound 4. Polar BPZ derivatives, those with a substituted amine or alcohol, were devoid of any inhibitory or proliferative effects. The remaining derivatives seem to lack sufficient lipophilicity to execute an overt toxic effect. Our results suggest that increasing the lipophilic character of BPZ enhances the cytotoxic effects.
Kinetic and molecular dynamic studies of inhibitors of shikimate dehydrogenase from methicillin‐resistant Staphylococcus aureus
Authors: Enríquez‐Mendiola Daniel , Téllez‐Valencia Alfredo , Sierra‐Campos Erick , Campos‐Almazán Mara , Valdez‐Solana Mónica , Gómez Palacio‐Gastélum Marcelo , Avitia‐Domínguez Claudia 
Published: April 2019

AbstractDue to its resistance to many antibiotics, methicillin‐resistant Staphylococcus aureus (MRSA) have become a worldwide health problem creating the urgent necessity of developing new drugs against this pathogen. In this sense, one approach is to search for inhibitors of important enzymes in its metabolism. According to this, the shikimate pathway is an important metabolic route in bacteria and its enzymes are considered as great targets for the development of new antibiotic drugs. One of these enzymes is the shikimate dehydrogenase that catalyzes the reversal reduction from 3‐dehydroshikimate to shikimate using NADPH as cofactor. In this work, four new compounds were found capable of inhibiting the shikimate dehydrogenase (SDH) from S. aureus (SaSDH) activity. A detailed kinetic characterization showed that the most potent inhibitor presented a Ki of 8 and 10 μM with respect to shikimate and NADP+, respectively, and a mixed partial inhibition mechanism for both substrates. Molecular dynamics studies revealed that the four inhibitors perturb the structure of SaSDH affecting important domains. Toxicological and physicochemical parameters indicated that these compounds can be considered as potential drugs. Therefore, these compounds are good hits that will help in the process to obtain a new drug against MRSA.
In vitro efficacy of three different implant surface decontamination methods in three different defect configurations
Authors: Keim David , Nickles Katrin , Dannewitz Bettina , Ratka Christoph , Eickholz Peter , Petsos Hari 
Published: April 2019

AbstractObjectivesEvaluation of in vitro efficacy of three different implant surface decontamination methods in a peri‐implant bone defect model.Material and methodsA total of 180 implants were stained with indelible red color and distributed to standardized peri‐implant bone defect resin models with a circumferential defect angulation of 30°, 60°, or 90° (supraosseous defect). Sixty implants were assigned to each type of defect. All implants were cleaned by the same examiner. For each type of defect, 20 implants were cleaned for 2 min with one of 3 devices: curette (CUR), sonicscaler (SOSC), or air abrasion with glycine powder (APA). Thereafter, photographs were taken from both sides of each implant and the cumulative uncleaned implant surface area was measured by color recognition technique. Scanning electron micrographs (SEM) were examined to assess morphologic surface damages.ResultsThe cleaning efficacy as percent (%) of residual color was significantly different for each of the 3 defect angulations (p < 0.001) for each treatment device: 30° CUR: 53.44% > SOSC: 19.69% > APA: 8.03%; 60° CUR: 57.13% > SOSC: 11.4% > APA: 0.13%; and 90° CUR: 48.1% > SOSC: 13.07% > APA: 0.58%. The differences between the three different cleaning modalities within each defect type were also significant (p < 0.005). SEM micrographs showed no surface damages after the use of APA.ConclusionAir powder abrasion is the most efficient (APA > SOSC > CUR) and less surface damaging treatment modality for each defect angulation in this in vitro model.
Echocardiographic imaging of the Medtronic Micro Vascular Plug™ during off label placement in the premature infant with patent ductus arteriosus
Authors: Berry James M. , Hiremath Gurumurthy , Heal Elisabeth , Bass John L. 
Published: April 2019

ObjectivesTo report the usefulness of harmonic imaging in echocardiography to visualize and direct the implantation of the Medtronic micro vascular plug (MVP).BackgroundOff label use of the MVP was reported for transcatheter occlusion of patent ductus arteriosus (PDA) in premature infants. The device is poorly visible on fluoroscopy and echocardiography.MethodsIn 9 consecutive premature infants, the MVP was used for transcatheter closure of the PDA. In each, the ability of conventional echocardiographic imaging was compared to harmonic imaging, and the device was deployed in the PDA using echocardiography.ResultsIn each subject, harmonic imaging proved superior to conventional echocardiography to visualize the MVP in premature infants using 12 and 8 MHz probes. Once the delivery, catheter was across the PDA into the descending aorta, and the MVP advanced to the catheter tip, positioning, and deployment of the device was possible without fluoroscopy. All devices were deployed appropriately with immediate occlusion and no obstruction to the left pulmonary artery or aorta.ConclusionsThe MVP can be accurately imaged using harmonic imaging, even in the near field in premature infants. Precise implantation of the MVP in the PDA of premature infants is possible with echocardiographic imaging of the device and vascular structures.
Accelerometer activity tracking in horses and the effect of pasture management on time budget
Authors: Maisonpierre I. N. , Sutton M. A. , Harris P. , Menzies‐Gow N. , Weller R. , Pfau T. 
Published: April 2019

SummaryBackgroundAccelerometry is an accepted means of quantifying human physical activity. Quantitative physical activity tracking could be beneficial for studies into equine health and disease prevention, for example in relation to obesity management.ObjectivesValidate accelerometer use in grazing horses, determine between‐day repeatability, and assess the effects of pasture size on time budget (i.e. duration in each activity category).Study designProof of concept.MethodsAccelerometers (ActiGraph) were positioned at the poll. Horses underwent 5 min of observed activity in three categories: standing, grazing and ambulating. Receiver‐operating characteristic curve analysis, used on ten second data epochs, calculated cut points between the activities. A 20‐day study was then undertaken on 6 horses at pasture. Time in each category (per day) was deduced; a Mann Whitney U test was performed to compare standard vs. small paddock and day vs. night turn out.ResultsCut‐off values with the optimum sensitivity (94.7–97.7%) and specificity (94.7–96.8%) were found to be <127.6 counts for standing, 127.6–702.7 counts for grazing and >702.7 counts for ambulating. Repeatability was analysed descriptively: Median (IQR) of the between‐day difference in minutes standing, grazing and ambulating were 46.9 (21.3–87.9), 77.3 (40.2–124.5) and 15.6 (6.8–40.2) respectively. Median times standing and ambulating were significantly different between standard and small paddocks: standing: 8.7 vs. 10.3 h (P<0.001); ambulating: 55.7 vs. 39.6 min (P = 0.002). There was no significant difference in the median time spent grazing. There were significant differences between day and night: standing: 32.95% vs. 50.97% (P = 0.001), grazing: 60.81% vs. 46.77% (P<0.001) and ambulating: 4.57% vs. 2.40% (P<0.001).Main limitationsSmall sample size and lack of cross‐validation of cut‐off points on independent, ‘unseen’ data.ConclusionsAccelerometry can differentiate standing, grazing and ambulating in horses. Our proof‐of‐concept study demonstrates modifying pasture size influences activity budgets; opening avenues into studying obesity management.
State ownership and banks’ information rents: Evidence from China
Authors: Yu Fengyan , Liang Qi , Wang Wei 
Published: April 2019

AbstractIn a lending relationship, a bank with an information advantage regarding its client tends to hold up the borrower and charge higher interest rates. We conjecture that state‐owned enterprises (SOEs), with worse information asymmetry, are subject to greater information rents. State‐owned banks place less emphasis on information production and hence extract lower rents compared to profit‐maximizing private banks. We use the decline of loan interest rates around the borrowers’ equity initial public offerings (IPOs) as the proxy of banks’ information rents. We find SOEs in China experience larger declines in loan interest rates around their IPOs; the central government‐controlled Big Four banks exhibit smaller declines in rates they charge, and their rate declines concentrate on loans made to SOEs.