160 research outputs found

    Preliminary investigations on the single and combined cytotoxic effect of T-2 and HT-2 measured by Methyl Thiazol Tetrazolium (MTT) cytotoxicity test using pig lymphocytes

    Get PDF
    Fusariotoxins are frequently existing contaminants in cereal and other plant products. High relationship was found between the levels of the trichothecene T-2 and HT-2 toxin detected in contaminated commodities. Many in vitro studies investigated the cytotoxicity of T-2 and HT-2, but the interaction between them has not been thoroughly studied yet. The aim of the study was to examine the dose dependent cytotoxic effect of T-2 and HT-2 toxins, single and in combination, using pig lymphocytes in the methyl thiazol tetrazolium (MTT ) assay. The mycotoxins were added at various concentrations, i.e. 0.5, 0.1, 0.05, 0.01 and 0.001 μM of T-2; 1.0, 0.5, 0.2., 0.1 and 0.05 μM of HT-2; and both mycotoxins combined. Two exposure times (6 and 24 h) were tested. Both T-2 and HT-2 toxins exerted a dose dependent effect. After 6 h incubation, the increase in concentration of T-2 from 0.001 to 0.5 μM and HT-2 for 0.05 to 1.0 μM resulted in lower cell viability by 22 and 17%, respectively. After 24 h cell viability was significantly lower compared to values obtained at 6 h, except 0.5 μM T-2 and 0.05, 1.0 μM HT-2, respectively. Measured cell viability for combinations of T-2 and HT-2 was higher compared to the calculated expected values. The two toxins caused lower cell survival when applied together than in single administration after 6 h incubation. After 24 h incubation this tendency was not consistent

    Post-socialist housing systems in Europe:Housing welfare regimes by default?

    Get PDF
    This article develops a conceptual framework derived from welfare regime and concomitant literatures to interpret housing reform in post-socialist European countries. In it, settled power structures and collective ideologies are necessary prerequisites for the creation of distinctive housing welfare regimes with clear roles for the state, market and households. Although the defining feature of post-socialist housing has been mass-privatisation to create super-homeownership societies, the emphatic retreat of the state that this represents has not been replaced by the creation of the institutions or cultures required to create fully financialised housing markets. There is, instead, a form of state legacy welfare in the form of debt-free home-ownership, which creates a gap in housing welfare that has been partially filled by households in the form of intergenerational assistance (familialism) and self-build housing. Both of these mark continuities with the previous regime. The latter is especially common in south-east Europe where its frequent illegality represents a form of anti-state housing. The lack of settled ideologies and power structures suggests that these housing welfare regimes by default will persist as part of a process that resembles a path-dependent ‘transformation’ rather than ‘transition’

    Macromolecular theory of solvation and structure in mixtures of colloids and polymers

    Full text link
    The structural and thermodynamic properties of mixtures of colloidal spheres and non-adsorbing polymer chains are studied within a novel general two-component macromolecular liquid state approach applicable for all size asymmetry ratios. The dilute limits, when one of the components is at infinite dilution but the other concentrated, are presented and compared to field theory and models which replace polymer coils with spheres. Whereas the derived analytical results compare well, qualitatively and quantitatively, with mean-field scaling laws where available, important differences from ``effective sphere'' approaches are found for large polymer sizes or semi-dilute concentrations.Comment: 23 pages, 10 figure

    Effects of monosodium-L-glutamate administration on serum levels of reproductive hormones and cholesterol, epididymal sperm reserves and testicular histomorphology of male albino rats

    Get PDF
    This study investigated the effects of administration of monosodium L-glutamate (MSG) on serum gonadotrophin-releasing hormone (GnRH), luteinising hormone (LH), testosterone and total cholesterol (TC), cauda epididymal sperm reserves (CESR) and testicular histomorphology of adult male albino rats. Eighty-four rats, randomly assigned to 7 groups of 12 rats each, were used for the study. Varying low doses (0.25, 0.50 or 1.00 g/kg body weight) of MSG were administered orally or subcutaneously at 48-h intervals for six weeks. Serum GnRH, LH, testosterone and TC, and CESR were evaluated on days 14, 28 and 42 of MSG administration. Testicular histomorphology was evaluated on day 42. The results showed that the mean serum GnRH, LH and testosterone levels, and the CESR of all the treated groups were significantly (P < 0.05) lower than those of the untreated control on days 14, 28 and 42 of MSG administration. The mean serum TC levels of all the treated groups were also significantly (P < 0.05) lower than those of the control group on days 14 and 28. No lesions were observed on sections of the testes. It was concluded that MSG administration for 14, 28 and 42 days led to significantly lower serum levels of GnRH, LH, testosterone and TC, and significantly lower CESR

    A computational model for prediction of clot platelet content in flow-diverted intracranial aneurysms

    Get PDF
    Treatment of intracranial aneurysms with flow-diverting stents is a safe and minimally invasive technique. The goal is stable embolisation that facilitates stent endothelialisation, and elimination of the aneurysm. However, it is not fully understood why some aneurysms fail to develop a stable clot even with sufficient levels of flow reduction. Computational prediction of thrombus formation dynamics can help predict the post-operative response in such challenging cases. In this work, we propose a new model of thrombus formation and platelet dynamics inside intracranial aneurysms. Our novel contribution combines platelet activation and transport with fibrin generation, which is key to characterising stable and unstable thrombus. The model is based on two types of thrombus inside aneurysms: red thrombus (fibrin- and erythrocyte-rich) can be found in unstable clots, while white thrombus (fibrin- and platelet-rich) can be found in stable clots. The thrombus generation model is coupled to a CFD model and the flow-induced platelet index (FiPi) is defined as a quantitative measure of clot stability. Our model is validated against an in vitro phantom study of two flow-diverting stents with different sizing. We demonstrate that our model accurately predicts the lower thrombus stability in the oversized stent scenario. This opens possibilities for using computational simulations to improve endovascular treatment planning and reduce adverse events, such as delayed haemorrhage of flow-diverted aneurysms

    Rhetorical-Performative Analysis of the Urban Symbolic Landscape : Populism in Action

    Get PDF
    This chapter introduces a rhetorical-performative analysis as a tool for exploring urban symbolic landscape and populism and hence deals with relationality and materiality from the postfoundational perspective. It connects the articulation theory of cultural theorists Stuart Hall or political theorists Ernesto Laclau and Chantal Mouffe and spatial analysis of cultural geographer Doreen Massey to the study of populism. The case of Hungary shows how political frontiers have been articulated in the public space, contestable interpretations of the past are deliberately used and key symbolic urban landscapes transformed radically to articulate a political ‘us’—and ‘them.’ In the 2010s, in the Hungarian capital Budapest, the top-down process transforming urban space faced bottom-up movements which reproduce the populist logic of articulation.Peer reviewe

    Dendritic cell-expressed common gamma-chain recruits IL-15 for trans-presentation at the murine immunological synapse [version 1]

    Get PDF
    Background: Mutations of the common cytokine receptor gamma chain (γc) cause Severe Combined Immunodeficiency characterized by absent T and NK cell development. Although stem cell therapy restores these lineages, residual immune defects are observed that may result from selective persistence of γc-deficiency in myeloid lineages. However, little is known about the contribution of myeloid-expressed γc to protective immune responses.  Here we examine the importance of γc for myeloid dendritic cell (DC) function. Methods: We utilize a combination of in vitro DC/T-cell co-culture assays and a novel lipid bilayer system mimicking the T cell surface to delineate the role of DC-expressed γc during DC/T-cell interaction. Results: We observed that γc in DC was recruited to the contact interface following MHCII ligation, and promoted IL-15Rα colocalization with engaged MHCII. Unexpectedly, trans-presentation of IL-15 was required for optimal CD4+T cell activation by DC and depended on DC γc expression. Neither recruitment of IL-15Rα nor IL-15 trans-signaling at the DC immune synapse (IS), required γc signaling in DC, suggesting that γc facilitates IL-15 transpresentation through induced intermolecular cis associations or cytoskeletal reorganization following MHCII ligation. Conclusions: These findings show that DC-expressed γc is required for effective antigen-induced CD4+ T cell activation. We reveal a novel mechanism for recruitment of DC IL-15/IL-15Rα complexes to the IS, leading to CD4+ T cell costimulation through localized IL-15 transpresentation that is coordinated with antigen-recognition

    Dendritic cell-expressed common gamma-chain recruits IL-15 for trans-presentation at the murine immunological synapse [version 2; referees: 2 approved]

    Get PDF
    BACKGROUND: Mutations of the common cytokine receptor gamma chain (γc) cause Severe Combined Immunodeficiency characterized by absent T and NK cell development. Although stem cell therapy restores these lineages, residual immune defects are observed that may result from selective persistence of γc-deficiency in myeloid lineages. However, little is known about the contribution of myeloid-expressed γc to protective immune responses.  Here we examine the importance of γc for myeloid dendritic cell (DC) function. METHODS: We utilize a combination of in vitro DC/T-cell co-culture assays and a novel lipid bilayer system mimicking the T cell surface to delineate the role of DC-expressed γc during DC/T-cell interaction. RESULTS: We observed that γc in DC was recruited to the contact interface following MHCII ligation, and promoted IL-15Rα colocalization with engaged MHCII. Unexpectedly, trans-presentation of IL-15 was required for optimal CD4+T cell activation by DC and depended on DC γc expression. Neither recruitment of IL-15Rα nor IL-15 trans-signaling at the DC immune synapse (IS), required γc signaling in DC, suggesting that γc facilitates IL-15 transpresentation through induced intermolecular cis associations or cytoskeletal reorganization following MHCII ligation. CONCLUSION: These findings show that DC-expressed γc is required for effective antigen-induced CD4+ T cell activation. We reveal a novel mechanism for recruitment of DC IL-15/IL-15Rα complexes to the IS, leading to CD4+ T cell costimulation through localized IL-15 transpresentation that is coordinated with antigen-recognition

    Investigation into the formation of the scrape-off layer density shoulder in JET ITER-like wall L-mode and H-mode plasmas

    Get PDF
    The low temperature boundary layer plasma (Scrape-Off-Layer or SOL) between the hot core and the surrounding vessel determines the level of power-loading, erosion and implantation of material surfaces, and thus the viability of tokamak-based fusion as an energy source. This study explores mechanisms affecting the formation of flattened density profiles, so-called ‘density shoulders’, in the low-field side (LFS) SOL, which modify ion and neutral fluxes to surfaces – and subsequent erosion. There is evidence against local enhancement of ionization inducing shoulder formation. We find that increases in SOL parallel resistivity, Λdiv (=[L||νei Ωi ]/cs Ωe), postulated to lead to shoulder growth through changes in SOL turbulence characteristics, correlates with increases in upstream SOL shoulder amplitude, As only under a subset of conditions (D2-fuelled L-mode density scans with outer strike point on the horizontal target). Λdiv fails to correlate with As for cases of N2 seeding or during sweeping of the strike point across the horizontal target. The limited correlation of Λdiv with As was also found for H-mode discharges. Thus, while Λdiv above a threshold of ~1 may be necessary for shoulder formation and/or growth, another shoulder mechanism is required. More significantly we find that in contrast to parallel resistivity, outer divertor recycling as quantified by the total outer divertor Balmer Dα emission, I-Dα, does scale with shoulder amplitude where Λdiv does and even where Λdiv fails. Divertor recycling could lead to SOL density shoulder formation through: a) reducing the parallel to the field flow (loss) of ions out of the SOL to the divertor; and b) changes in radial electric fields which lead to ExB poloidal flows as well as potentially affecting the SOL turbulence birth characteristics. Thus changes in divertor recycling may be the sole process in bringing about SOL density shoulders or in tandem with parallel resistivity

    Neutral pathways and heat flux widths in vertical- and horizontal-target EDGE2D-EIRENE simulations of JET

    Get PDF
    This paper further analyses the EDGE2D-EIRENE simulations presented by Chankin et al (2017 Nucl. Mater. Energy 12 273), of L-mode JET plasmas in vertical-vertical (VV) and Vertical-horizontal (VH) divertor configurations. As expected, the simulated outer divertor ionisation source peaks near the separatrix in VV and radially further out in VH. We identify the reflections of recycled neutrals from lower divertor tiles as the primary mechanism by which ionisation is concentrated on the outer divertor separatrix in the VV configuration. These lower tile reflection pathways (of neutrals from the outer divertor, and to an even greater extent from the inner divertor) dominate the outer divertor separatrix ionisation. In contrast, the lower-tile-reflection pathways are much weaker in the VH simulation and its outer divertor ionisation is dominated by neutrals which do not reflect from any surfaces. Interestingly, these differences in neutral pathways give rise to strong differences in the heat flux density width λq at the outer divertor entrance: λq = 3.2 mm in VH compared to λq = 11.8 mm in VV. In VH, a narrow channel exists in the near scrape-off-layer (SOL) where the convected heat flux, driven by strong Er × B flow and thermoelectric current, dominates over the conducted heat flux. The width of this channel sets λq and is determined by the radial distance between the separatrix and the ionisation peak in the outer divertor
    corecore