julilili42/papers huggingface dataset:
Erythrocyte Shrinkage and Cell Membrane Scrambling after Exposure to the Ionophore Nonactin
2015-08-17

Abstract The ionophore antibiotic nonactin permeabilizes cell membranes to and K + . Treatment of erythrocytes with nonactin is expected to trigger cellular K + loss with subsequent cell shrinkage, which in turn is known to trigger suicidal death of a wide variety of cells including erythrocytes. This study explored whether nonactin exposure induces eryptosis, the suicidal erythrocyte death characterized by cell shrinkage and translocation of cell membrane phosphatidylserine to the erythrocyte surface. Signalling of eryptosis includes increase in cytosolic Ca 2+ activity [(Ca 2+ ) i ] and stimulation of protein kinase C ( PKC ) as well as p38 mitogen‐activated protein kinase. Phosphatidylserine abundance at the cell surface was estimated from annexin‐V‐binding, cell volume from forward scatter (FSC) and (Ca 2+ ) i from Fluo3‐fluorescence. A 48‐hr treatment of human erythrocytes with nonactin significantly decreased FSC (≥10 ng/ml) and significantly increased the percentage of annexin‐V‐binding cells (≥10 ng/ml), effects paralleled by increase in (Ca 2+ ) i (≥50 ng/ml) and virtually abrogated by increase in extracellular K + concentration to 120 mM at the expense of Na + . The up‐regulation of annexin‐V‐binding after nonactin treatment was significantly blunted but not abolished by the removal of extracellular Ca 2+ and by addition of either PKC inhibitor staurosporine (0.4 μM) or p38 kinase inhibitor SB 203580 (2 μM). In conclusion, exposure of erythrocytes to the K + ionophore nonactin induces erythrocyte shrinkage and subsequent erythrocyte membrane scrambling, effects involving cellular K + loss, Ca 2+ entry and activation of staurosporine as well as SB 203580‐sensitive kinases.
A model of competition between multinationals
2015-08-17

This study models competition between multinationals sequentially entering the same market, and analyzes how they choose their entry modes between trade, greenfield investment and acquisition, and how competition amongst them affects their choices. I discuss two important factors that lead a multinational whether or not to acquire a local firm: the intensity of pre- and post-acquisition competition. The former determines both the acquisition price and the profitability of the next best alternative entry mode, whereas the latter determines the extent of business stealing by the rival. The results point to a non-linear relationship between trade and investment liberalization and foreign direct investment.
Surface Glycopolymers Are Crucial for In Vitro Anti-Wall Teichoic Acid IgG-Mediated Complement Activation and Opsonophagocytosis of Staphylococcus aureus
2015-08-18

ABSTRACT The cell envelopes of many Gram-positive bacteria contain wall teichoic acids (WTAs). Staphylococcus aureus WTAs are composed of ribitol phosphate (RboP) or glycerol phosphate (GroP) backbones substituted with d -alanine and N -acetyl- d -glucosamine (GlcNAc) or N -acetyl- d -galactosamine (GalNAc). Two WTA glycosyltransferases, TarM and TarS, are responsible for modifying the RboP WTA with α-GlcNAc and β-GlcNAc, respectively. We recently reported that purified human serum anti-WTA IgG specifically recognizes β-GlcNAc of the staphylococcal RboP WTA and then facilitates complement C3 deposition and opsonophagocytosis of S. aureus laboratory strains. This prompted us to examine whether anti-WTA IgG can induce C3 deposition on a diverse set of clinical S. aureus isolates. To this end, we compared anti-WTA IgG-mediated C3 deposition and opsonophagocytosis abilities using 13 different staphylococcal strains. Of note, the majority of S. aureus strains tested was recognized by anti-WTA IgG, resulting in C3 deposition and opsonophagocytosis. A minority of strains was not recognized by anti-WTA IgG, which correlated with either extensive capsule production or an alteration in the WTA glycosylation pattern. Our results demonstrate that the presence of WTAs with TarS-mediated glycosylation with β-GlcNAc in clinically isolated S. aureus strains is an important factor for induction of anti-WTA IgG-mediated C3 deposition and opsonophagocytosis.
Influence of Feature Encoding and Choice of Classifier on Disease Risk Prediction in Genome-Wide Association Studies
2015-08-18

Various attempts have been made to predict the individual disease risk based on genotype data from genome-wide association studies (GWAS). However, most studies only investigated one or two classification algorithms and feature encoding schemes. In this study, we applied seven different classification algorithms on GWAS case-control data sets for seven different diseases to create models for disease risk prediction. Further, we used three different encoding schemes for the genotypes of single nucleotide polymorphisms (SNPs) and investigated their influence on the predictive performance of these models. Our study suggests that an additive encoding of the SNP data should be the preferred encoding scheme, as it proved to yield the best predictive performances for all algorithms and data sets. Furthermore, our results showed that the differences between most state-of-the-art classification algorithms are not statistically significant. Consequently, we recommend to prefer algorithms with simple models like the linear support vector machine (SVM) as they allow for better subsequent interpretation without significant loss of accuracy.
Children With ADHD Show Impairments in Multiple Stages of Information Processing in a Stroop Task: An ERP Study
2015-08-18

This study investigated the role of impaired inhibitory control as a factor underlying attention deficit hyperactivity disorder (ADHD). Children with ADHD and typically developing children completed an animal Stroop task while electroencephalogram (EEG) was recorded. The lateralized readiness potential and event-related brain potentials associated with perceptual and conflict processing were analyzed. Children with ADHD were slower to give correct responses irrespective of congruency, and slower to prepare correct responses in the incongruent condition. This delay could result from enhanced effort allocation at earlier processing stages, indicated by differences in P1, N1, and conflict sustained potential. Results suggest multiple deficits in information processing rather than a specific response inhibition impairment.
The influence of stimulus repetition on duration judgments with simple stimuli
2015-08-18

Two experiments investigated the effects of stimulus repetition vs. stimulus novelty on perceived duration. In a reminder task, a standard and a comparison stimulus were presented consecutively in each trial, and the comparison was either a repetition of the standard or a different stimulus. Pseudowords (Experiment 1) or strings of consonants (Experiment 2) were used as stimuli and the inter-stimulus interval (ISI) between the standard and the comparison was either constant or variable. Participants were asked to judge whether the comparison was shorter or longer than the standard. In both experiments, we observed shorter judged durations for repeated than for novel comparisons whereas the manipulation of the ISI had no pronounced effects on duration judgments. The finding of shorter duration judgments for repeated as compared to novel nonwords replicates the results of a previous study (Matthews, 2011) which employed highly complex stimulus material. The present study shows that changes of simple, semantically meaningless stimuli are sufficient to result in a shorter perceived duration of repeated as compared to novel stimuli.
Oncogenic features of the bone morphogenic protein 7 (BMP7) in pheochromocytoma
2015-08-18

BMP7 is a growth factor playing pro- or anti-oncogenic roles in cancer in a cell type-dependent manner. We previously reported that the BMP7 gene is overexpressed in pheochromocytomas (PCCs) developing in MENX-affected rats and human patients. Here, analyzing a large cohort of PCC patients, we found that 72% of cases showed elevated levels of the BMP7 protein. To elucidate the role of BMP7 in PCC, we modulated its levels in PCC cell lines (overexpression in PC12, knockdown in MPC and MTT cells) and conducted functional assays. Active BMP signaling promoted cell proliferation, migration, and invasion, and sustained survival of MENX rat primary PCC cells. In PCC, BMP7 signals through the PI3K/AKT/mTOR pathway and causes integrin β1 up-regulation. Silencing integrin β1 in PC12 cells suppressed BMP7-mediated oncogenic features. Treatment of MTT cells with DMH1, a novel BMP antagonist, suppressed proliferation and migration. To verify the clinical applicability of our findings, we evaluated a dual PI3K/mTOR inhibitor (NVP-BEZ235) in MENX-affected rats in vivo. PCCs treated with NVP-BEZ235 had decreased proliferation and integrin β1 levels, and higher apoptosis. Altogether, BMP7 activates pro-oncogenic pathways in PCC. Downstream effectors of BMP7-mediated signaling may represent novel targets for treating progressive/inoperable PCC, still orphan of effective therapy.
High-Pitch Low-Dose Whole-Body Computed Tomography for the Assessment of Ventriculoperitoneal Shunts in a Pediatric Patient Model
2015-08-18

In this experimental ex vivo pediatric patient model, LD-CT yields excellent sensitivity for the detection of VP shunt complications at higher diagnostic confidence and lower radiation exposure compared with SS.
Multiscale modelling of vascular dependent tumor growth in hepatocellular carcinoma (HCC) under therapy with transarterial chemoembolization (TACE)
2015-08-18

Background and Aims: TACE is an established option in advanced HCC. Despite complete disruption of blood flow by imaging, a distinct number of tumor cells survive that are responsible for tumor regrowth. To investigate the influence of different parameters that determine TACE efficacy, a multiscale model was developed to study the evolution of vascular supply and angiogenesis. This mathematical model is informed, parameterized and directly validated using clinical data, based on 43 patients. The aim was to get new hypothesis to improve the efficacy of TACE.
Cofilin-1-mediated growth regulation in pancreatic cancer cells is associated with downregulation of Gli1 and increased activity of the MAL/SRF transcription factor complex
2015-08-18

Introduction: We have previously described a multi-step high-content screening approach to identify novel functionally relevant target genes in pancreatic ductal adenocarcinoma (Buchholz et al., PLoS-One, in press). The results of these analyses predicted an unexpected and previously undocumented role for the small actin-binding protein cofilin-1 in growth control of pancreatic cancer cells.
Direct observation of conductive filament formation in Alq3 based organic resistive memories
2015-08-19

This work explores resistive switching mechanisms in non-volatile organic memory devices based on tris(8-hydroxyquinolie)aluminum (Alq3). Advanced characterization tools are applied to investigate metal diffusion in ITO/Alq3/Ag memory device stacks leading to conductive filament formation. The morphology of Alq3/Ag layers as a function of the metal evaporation conditions is studied by X-ray reflectivity, while depth profile analysis with X-ray photoelectron spectroscopy and time-of-flight secondary ion mass spectrometry is applied to characterize operational memory elements displaying reliable bistable current-voltage characteristics. 3D images of the distribution of silver inside the organic layer clearly point towards the existence of conductive filaments and allow for the identification of the initial filament formation and inactivation mechanisms during switching of the device. Initial filament formation is suggested to be driven by field assisted diffusion of silver from abundant structures formed during the top electrode evaporation, whereas thermochemical effects lead to local filament inactivation.
Metabolic alteration – Overcoming therapy resistance in gastric cancer via PGK-1 inhibition in a combined therapy with standard chemotherapeutics
2015-08-19

We showed a significant decrease in cell viability after the simultaneous application of chemotherapeutics and adenovirus. These results suggest that PGK1-inhibition is able to increase the vulnerability of gastric cancer cells and tumor stem cells to overcome the chemotherapeutic therapy resistance.
Intercorrelation of Electronic, Structural, and Morphological Properties in Nanorods of 2,3,9,10-Tetrafluoropentacene
2015-08-19

We evidence the intercorrelation of electronic, structural, and morphological properties in nanorods of a substituted fluorine-based pentacene, 2,3,9,10-tetrafluoropentacene, deposited on gold single crystals by using photoemission and X-ray absorption spectroscopy investigations. Our investigations show changes in the XPS spectroscopy lines, and NEXAFS features correlate with the specific structure of the assemblies and their morphology. Consequently, the chemical structure affects not only the molecular electronic structure and the way the molecules assemble in a film but also the film morphology leading to specific thin film electronic properties.
Comparison of Phytoscreening and Direct‐Push‐Based Site Investigation at a Rural Megasite Contaminated with Chlorinated Ethenes
2015-08-19

Abstract The reliable characterization of subsurface contamination of spatially extended contaminated sites is a challenging task, especially with an unknown history of land use. Conventional technologies often fail due to temporal and financial constraints and thus hinder the redevelopment of abandoned areas in particular. Here we compare two site screening techniques that can be applied quickly at relatively low cost, namely Direct Push ( DP )‐based groundwater sampling and tree core sampling. The effectiveness of both methods is compared for a rural megasite contaminated with chlorinated hydrocarbons. Unexpected pollution hot spots could be identified using both of these methods, while tree coring even enabled the delineation of the contaminant plume flowing into an adjacent wetland inaccessible for DP units. Both methods showed a good agreement in revealing the spatial pattern of the contamination. The correlation between groundwater concentrations and equivalent concentrations in wood was linear and highly significant for trichloroethene. Correlation was less obvious for its metabolite cis ‐dichloroethene, but still significant. As outcome of our study we recommend tree coring and for initial screening in combination with a DP sampling to retrieve quantitative data on groundwater pollutants in order to assess the contamination situation of a non‐ or only partly investigated site. The subsequent placement of monitoring wells for long‐term monitoring of contamination levels is recommended. A combination of methods would achieve more relevant information at comparable or possibly even lower efforts in comparison to a conventional site investigation.
Fluorescence microscopy of Streptomyces conjugation suggests DNA‐transfer at the lateral walls and reveals the spreading of the plasmid in the recipient mycelium
2015-08-19

Summary Conjugative DNA ‐transfer in mycelial streptomycetes is a unique process, manifested on agar plates by the formation of circular growth retardation zones called pocks. Because pock size correlates with the extent of the transconjugant zone, it was suggested that pocks reflect the spreading of the transferred plasmid in the recipient mycelium. However, this concept has not been experimentally proven yet. The use of an e GFP ‐encoding derivative of the conjugative pIJ 303 plasmid and S treptomyces lividans T 7‐ mC herry as recipient enabled us to differentiate donor, recipient and transconjugant hyphae in mating experiments by fluorescence microscopy. Microscopic observation of the conjugation process suggested DNA ‐transfer via the lateral walls. At the contact sites mC herry was never observed in the donor, indicating that the conjugative DNA ‐transfer does not involve interfusion of cytoplasms of donor and recipient. The spreading of the transferred plasmid to the older parts of the recipient mycelium was demonstrated. This spreading was impaired when plasmid‐encoded spd genes were inactivated. Deletion of the FtsK ‐like DNA ‐translocase encoding tra gene from the plasmid and mating experiments with strains containing chromosomal copies of tra either in the donor and/or in the recipient revealed that Tra had an essential role in intramycelial plasmid spreading.
CD4+CD25hiFOXP3+ Regulatory T Cells and Cytokine Responses in Human Schistosomiasis before and after Treatment with Praziquantel
2015-08-20

Schistosoma-associated CD4+CD25hiFOXP3+Tregs exert a suppressive effect on both proliferation and cytokine production. Although Treg frequency decreases after praziquantel treatment, their suppressive capacity remains unaltered when considering cytokine production whereas their influence on proliferation weakens with treatment.
Evolutionarily distant pathogens require the Arabidopsis phytosulfokine signalling pathway to establish disease
2015-08-20

Abstract Secreted peptides and their specific receptors frequently orchestrate cell‐to‐cell communication in plants. Phytosulfokines (PSKs) are secreted tyrosine‐sulphated peptide hormones, which trigger cellular dedifferentiation and redifferentiation upon binding to their membrane receptor. Biotrophic plant pathogens frequently trigger the differentiation of host cells into specialized feeding structures, which are essential for successful infection. We found that oomycete and nematode infections were characterized by the tissue‐specific transcriptional regulation of genes encoding Arabidopsis PSKs and the PSK receptor 1 (PSKR1). Subcellular analysis of PSKR1 distribution showed that the plasma membrane‐bound receptor internalizes after binding of PSK‐α. Arabidopsis pskr1 knockout mutants were impaired in their susceptibility to downy mildew infection. Impaired disease susceptibility depends on functional salicylic acid (SA) signalling, but not on the massive up‐regulation of SA‐associated defence‐related genes. Knockout pskr1 mutants also displayed a major impairment of root‐knot nematode reproduction. In the absence of functional PSKR1, giant cells arrested their development and failed to fully differentiate. Our findings indicate that the observed restriction of PSK signalling to cells surrounding giant cells contributes to the isotropic growth and maturation of nematode feeding sites. Taken together, our data suggest that PSK signalling in Arabidopsis promotes the differentiation of host cells into specialized feeding cells.
Health-related gender boundary crossing in youth elite sport
2015-08-20

Gender has been found to play an important role in moderating health outcomes and behaviours. However, strong similarities in male and female athletes' handling of pain and injury have been noted. The dominance of health practices associated with 'orthodox masculinity' references elite sport's risky body culture. Drawing on the concept of 'gender boundary crossing', we question how athletes negotiate orthodox masculine health practices and body–self relationships in the process of socialization. Our analysis draws on qualitative interviews with male and female athletes aged 14–19 performing at the national level in German youth elite sport. Our findings indicate that while practices of pain ignorance and instrumental body relations dominate among female and male adolescent athletes, some develop less orthodox practices such as caring for the body and avoiding health risks. Critical events and alternative social networks were found to promote this health-related gender boundary crossing in elite sport.
Transport efficiency and dynamics of hydraulic fracture networks
2015-08-21

Intermittent fluid pulses in the Earth's crust can explain a variety of geological phenomena, for instance the occurrence of hydraulic breccia. Fluid transport in the crust is usually modeled as continuous Darcian flow, ignoring that sufficient fluid overpressure can cause hydraulic fractures as fluid pathways with very dynamic behavior. Resulting hydraulic fracture networks are largely self-organized: opening and healing of hydraulic fractures depends on local fluid pressure, which is, in turn, largely controlled by the fracture network. We develop a crustal-scale 2D computer model designed to simulate this process. To focus on the dynamics of the process we chose a setup as simple as possible. Control factors are constant overpressure at a basal fluid source and a constant "viscous" parameter controlling fracture-healing. Our results indicate that at large healing rates hydraulic fractures are mobile, transporting fluid in intermittent pulses to the surface and displaying a 1/fα behavior. Low healing rates result in stable networks and constant flow. The efficiency of the fluid transport is independent from the closure dynamics of veins or fractures. More important than preexisting fracture networks is the distribution of fluid pressure. A key requirement for dynamic fracture networks is the presence of a fluid pressure gradient.
Is unique scaling of aquifer macrodispersivity supported by field data?
2015-08-22

Spreading of conservative solutes in groundwater due to aquifer heterogeneity is quantified by the macrodispersivity, which was found to be scale dependent. It increases with travel distance, stabilizing eventually at a constant value. However, the question of its asymptotic behavior at very large scale is still a matter of debate. It was surmised in the literature that macrodispersivity scales up following a unique scaling law. Attempts to define such a law were made by fitting a regression line in the log-log representation of an ensemble of macrodispersivities from multiple experiments. The functional relationships differ among the authors, based on the choice of data. Our study revisits the data basis, used for inferring unique scaling, through a detailed analysis of literature marcodispersivities. In addition, values were collected from the most recent tracer tests reported in the literature. We specified a system of criteria for reliability and reevaluated the reliability of the reported values. The final collection of reliable estimates of macrodispersivity does not support a unique scaling law relationship. On the contrary, our results indicate, that the field data can be explained as a collection of macrodispersivities of aquifers with varying degree of heterogeneity where each exhibits its own constant asymptotic value. Our investigation concludes that transport, and particularly the macrodispersivity, is formation-specific, and that modeling of transport cannot be relegated to a unique scaling law. Instead, transport requires characterization of aquifer properties, e.g., spatial distribution of hydraulic conductivity, and the use of adequate models.
Capillary isoelectric focusing‐mass spectrometry: Coupling strategies and applications
2015-08-24

IEF on immobilized pH gradient strips is a widespread tool for protein separation, especially as first dimension in commonly utilized 2DE. In the latter arrangement, separations are based on two orthogonal molecular characteristics according to p I in the first and molecular weight in the second dimension. However, the approach is time consuming, quantification is difficult and MS can be applied only offline. Capillary IEF and related IEF techniques in combination with MS provide similar information. The major benefits are high mass resolution and mass accuracy, reproducibility, speed, automation, and quantification by using a high‐resolution mass spectrometer. However, online hyphenation of CIEF with MS is interfered by the ampholytes, acids, and bases needed for high‐resolution IEF. This review will give an overview about important coupling techniques, like low ampholyte concentration, interim separation by chromatography, or the use of a dialysis interface to separate the analytes from interfering substances. It is focused on strategies which allow sensitive MS detection of CIEF‐separated analytes. In addition, proteomic and biopharmaceutical applications of capillary IEF techniques combined with MS are briefly summarized.