1,077 research outputs found

    Autoantibodies against retinal proteins in paraneoplastic and autoimmune retinopathy

    Get PDF
    BACKGROUND: Autoimmune retinal degeneration may occur in patients who present with sudden or, less commonly, subacute loss of vision of retinal origin, associated with an abnormal ERG, through the action of autoantibodies against retinal proteins. Often the patients are initially diagnosed with or suspected of having a paraneoplastic retinopathy (PR), such as cancer-associated retinopathy (CAR). However, there is limited information on the occurrence, the specificity of autoantibodies in these patients, and their association with clinical symptoms. METHODS: Sera were obtained from 193 retinopathy patients who presented with clinical symptoms resembling PR or autoimmune retinopathy (AR), including sudden painless loss of vision, typically associated with visual field defects and photopsias, and abnormal rod and/or cone responses on the electroretinogram (ERG). Sera were tested for the presence of anti-retinal autoantibodies by Western blot analysis using proteins extracted from human retina and by immunohistochemistry. Autoantibody titers against recoverin and enolase were measured by ELISA. RESULTS: We identified a higher prevalence of anti-retinal autoantibodies in retinopathy patients. Ninety-one patients' sera (47.1%) showed autoantibodies of various specificities with a higher incidence of antibodies present in retinopathy patients diagnosed with cancer (33/52; 63.5%; p = 0.009) than in retinopathy patients without cancer (58/141; 41.1%). The average age of PR patients was 62.0 years, and that of AR patients was 55.9 years. Autoantibodies against recoverin (p23) were only present in the sera of PR patients, autoantibodies against unknown p35 were more common in patients with AR, while anti-enolase (anti-p46) autoantibodies were nearly equally distributed in the sera of patients with PR and those with AR. In the seropositive patients, the autoantibodies persisted over a long period of time – from months to years. A rebound in anti-recoverin autoantibody titer was found to be associated with exacerbations in visual symptoms but not in the recurrence of cancer. When compared to sera from healthy subjects, autoantibodies against retinal proteins from both groups of patients were cytotoxic to retinal cells, indicating their pathogenic potential. CONCLUSIONS: These studies showed that patients with sudden or subacute, unexplained loss of vision of retinal origin have anti-retinal antibodies in a broad range of specificity and indicate the need for autoantibody screening. Follow-up tests of antibody levels may be useful as a biomarker of disease activity associated with worsening of vision. Moreover, the heterogeneity in autoantibody specificity may explain the variation and complexity of clinical symptoms in retinopathy patients

    Transverse momentum spectra of identified particles in high energy collisions with statistical hadronisation model

    Get PDF
    A detailed analysis is performed of transverse momentum spectra of several identified hadrons in high energy collisions within the framework of the statistical model of hadronisation. The effect of the decay chain following hadron generation is accurately taken into account. The considered centre-of-mass energies range from ~ 10 to 30 GeV in hadronic collisions (pi+ p, pp and Kp) and from ~ 15 to 45 GeV in e+e- collisions. A clear consistency is found between the temperature parameter extracted from the present analysis and that obtained from fits to average hadron multiplicities in the same collision systems. This finding indicates that in the hadronisation, the production of different particle species and their momentum spectra are two closely related phenomenons governed by one parameter.Comment: Talk given by F. Becattini in "Correlations and Fluctuations 2000", 12 pp., 11 figure

    Parton Branching in Color Mutation Model

    Get PDF
    The soft production problem in hadronic collisions as described in the eikonal color mutation branching model is improved in the way that the initial parton distribution is treated. Furry branching of the partons is considered as a means of describing the nonperturbative process of parton reproduction in soft interaction. The values of all the moments, and CqC_q, for q=2,...,5, as well as their energy dependences can be correctly determined by the use of only two parameters.Comment: 8 pages (LaTeX) + 2 figures (ps files), submitted to Phys. Rev.

    Multi-porous extension of anisotropic poroelasticity : linkage with micromechanics

    Get PDF
    We thank the Editor, Prof. Ronaldo Borja, Prof. Mark Kachanov, and anonyomus reviewers for careful reading of themanuscript and their insightful comments. This research was supported financially by the NERC grant: “Quantifying theAnisotropy of Poroelasticity in Stressed Rock”, NE/N007826/1 and NE/T00780X/1.Peer reviewe

    Multi-porous extension of anisotropic poroelasticity : consolidation and related coefficients

    Get PDF
    We thank the Editor, Prof. Ronaldo Borja, and anonymous reviewers for careful reading of the manuscript and theirinsightful comments. This research was supported financially by the NERC grant: “Quantifying the Anisotropy of Poroelasticity in Sstressed Rrock”, NE/N007826/1 and NE/T00780X/1Peer reviewe

    Uniaxial compression of 3D printed samples with voids: laboratory measurements compared with predictions from Effective Medium Theory

    Full text link
    3D printing technology offers the possibility of producing synthetic samples with accurately defined microstructures. As indicated by effective medium theory (EMT), the shapes, orientations, and sizes of voids significantly affect the overall elastic response of a solid body. By performing uniaxial compression tests on twenty types of 3D-printed samples containing voids of different geometries, we examine whether the measured effective elasticities are accurately predicted by EMT. To manufacture the sample, we selected printers that use different technologies; fused deposition modelling (FDM), and stereolithography (SLA). We show how printer settings (FDM case) or sample cure time (SLA case) affect the measured properties. We also examine the reproducibility of elasticity tests on identically designed samples. To obtain the range of theoretical predictions, we assume either uniform strain or uniform stress. Our study of over two hundred samples shows that measured effective elastic moduli can fit EMT predictions with an error of less than 5% using both FDM and SLA methods if certain printing specifications and sample design considerations are taken into account. Notably, we find that the pore volume fraction of the designed samples should be above 1% to induce a measurable softening effect, but below 5% to produce accurate EMT estimations that fit the measured elastic properties of the samples. Our results highlight both the strengths of EMT for predicting the effective properties of solids with low pore fraction volume microstructural configurations, and the limitations for high porosity microstructures.Comment: 43 pages, 19 figs, 9 table

    Transesterification of PHA to Oligomers Covalently Bonded with (Bio)Active Compounds Containing Either Carboxyl or Hydroxyl Functionalities

    Get PDF
    © 2015 The Authors. Published by Public Library of Science. This is an open access article available under a Creative Commons licence. The published version can be accessed at the following link on the publisher’s website: https://doi.org/10.1371/journal.pone.0120149This manuscript presents the synthesis and structural characterisation of novel biodegradable polymeric controlled-release systems of pesticides with potentially higher resistance to weather conditions in comparison to conventional forms of pesticides. Two methods for the preparation of pesticide-oligomer conjugates using the transesterification reaction were developed. The first method of obtaining conjugates, which consist of bioactive compounds with the carboxyl group and polyhydroxyalkanoates (PHAs) oligomers, is "one-pot" transesterification. In the second method, conjugates of bioactive compounds with hydroxyl group and polyhydroxyalkanoates oligomers were obtained in two-step method, through cyclic poly(3-hydroxybutyrate) oligomers. The obtained pesticide-PHA conjugates were comprehensively characterised using GPC, 1H NMR and mass spectrometry techniques. The structural characterisation of the obtained products at the molecular level with the aid of mass spectrometry confirmed that both of the synthetic strategies employed led to the formation of conjugates in which selected pesticides were covalently bonded to PHA oligomers via a hydrolysable ester bond

    Dual Stimuli-Responsive Polysaccharide Hydrogels Manufactured by Radiation Technique

    Get PDF
    Featured Application Stimuli-responsive hydrogels encompassing biobased polymers are anticipated for utilization in various fields, starting from drug delivery systems through temporal actuators and water reservoirs to biodegradable microelements and nutrient delivery depots. This paper describes the results of the radiation-induced crosslinking of polysaccharides modified with hydroxypropyl and carboxymethyl functional groups, hydroxypropylcellulose (HPC) and carboxymethylcellulose (CMC), respectively, without and with poly(ethylene glycol) diacrylate (PEGDA) as a crosslinking agent, to obtain dual stimuli-responsive hydrogels. The gels were characterized in terms of water uptake and gel fraction, parameters that mainly depend on the HPC-CMC compositions, but also on the macromer crosslinker content and the absorbed dose. The swelling of hydrogels is controlled by both the temperature, due to the amphiphilic character of HPC and pH, due to the anionic functional groups of CMC. In spite of a similar degree of substitution in both cellulose derivatives, 1.4 for HPC and 1.2 for CMC, the pH response of hydrogels with an equal content of both polysaccharides is considerably higher-a reduction in swelling of up to 95% with a decrease in the pH to 2 was recorded-than the response to thermal-stimulus-wherein a reduction in swelling of less than 70% with an increasing in temperature to 55 degrees C was found. These biopolymers-based hydrogels of specific, stimuli-responsive swelling properties are anticipated in applications where a combination of two stimuli is essential and biodegradation may be required

    Generalized Relativistic Meson Wave Function

    Full text link
    We study the most general, relativistic, constituent qqq{\overline q} meson wave function within a new covariant framework. We find that by including a tensor wave function component, a pure valence quark model is now capable of reproducing not only all static pion data (fπf_\pi, rπ2\langle r_\pi^2 \rangle) but also the distribution amplitude, form factor (Fπ(Q2))(F_\pi(Q^2)), and structure functions. Further, our generalized spin wave function provides a much better detailed description of meson properties than models using a simple relativistic extension of the S=L=0S=L=0 nonrelativistic wave function.Comment: 17 pages, REXTeX 3.0 file, (uuencoded postscript files of 8 figures appended
    corecore