1,711 research outputs found

    Alternative antibody for the detection of CA125 antigen: a European multicenter study for the evaluation of the analytical and clinical performance of the Access (R) OV Monitor assay on the UniCel (R) Dxl 800 Immunoassay System

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    Background: Cancer antigen CA125 is known as a valuable marker for the management of ovarian cancer. Methods: The analytical and clinical performance of the Access OV Monitor Immunoassay System (Beckman Coulter) was evaluated at five different European sites and compared with a reference system, defined as CA125 on the Elecsys System (Roche Diagnostics). Results: Total imprecision (%CV) of the OV Monitor ranged between 3.1% and 8.8%, and inter-laboratory reproducibility between 4.7% and 5.0%. Linearity upon dilution showed a mean recovery of 100% (SD+8.1%). Endogenous interferents had no influence on OV Monitor levels (mean recoveries: hemoglobin 107%, bilirubin 103%, triglycericles 103%). There was no high-dose hook effect up to 27,193 kU/L. Clinical performance investigated in sera from 1811 individuals showed a good correlation between the Access OV Monitor and Elecsys CA125 (R = 0.982, slope = 0.921, intercept = + 1.951). OV Monitor serum levels were low in healthy individuals (n = 267, median = 9.7 kU/L, 95th percentile = 30.8 kU/L), higher in individuals with various benign diseases (n = 549, medians = 10.9-16.4 kU/L, 95th percentiles = 44.2-355 kU/L) and even higher in individuals suffering from various cancers (n = 995, medians= 12.4-445 kU/L; 95th percentiles = 53.4-4664 kU/L). Optimal diagnostic accuracy for cancer detection against the relevant benign control group by the OV Monitor was found for ovarian cancer {[}area under the curve (AUC) 0.898]. Results for the reference CA125 assay were comparable (AUC 0.899). Conclusions: The Access OV Monitor provides very good methodological characteristics and demonstrates an excellent analytical and clinical correlation with Elecsys CA125. The best diagnostic accuracy for the OV Monitor was found in ovarian cancer. Our results also suggest a clinical value of the OV Monitor in other cancers

    A numerical method with properties of consistency in the energy domain for a class of dissipative nonlinear wave equations with applications to a Dirichlet boundary-value problem

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    In this work, we present a conditionally stable finite-difference scheme that consistently approximates the solution of a general class of (3+1)-dimensional nonlinear equations that generalizes in various ways the quantitative model governing discrete arrays consisting of coupled harmonic oscillators. Associated with this method, there exists a discrete scheme of energy that consistently approximates its continuous counterpart. The method has the properties that the associated rate of change of the discrete energy consistently approximates its continuous counterpart, and it approximates both a fully continuous medium and a spatially discretized system. Conditional stability of the numerical technique is established, and applications are provided to the existence of the process of nonlinear supratransmission in generalized Klein-Gordon systems and the propagation of binary signals in semi-unbounded, three-dimensional arrays of harmonic oscillators coupled through springs and perturbed harmonically at the boundaries, where the basic model is a modified sine-Gordon equation; our results show that a perfect transmission is achieved via the modulation of the driving amplitude at the boundary. Additionally, we present an example of a nonlinear system with a forbidden band-gap which does not present supratransmission, thus establishing that the existence of a forbidden band-gap in the linear dispersion relation of a nonlinear system is not a sufficient condition for the system to present supratransmission

    Comportamiento de la interfaz concreto-epoxi-FRP utilizando la teorĂ­a de mezclas serie/paralelo

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    Diversos estudios experimentales han mostrado que uno de los factores que afectan el comportamiento de estructuras de concreto externamente reforzadas con Fiberglass Reinforced Plastic (FRP, por sus siglas en inglés) es la adherencia entre el concreto y el FRP. En complemento a la experimentación, en este artículo se propone el uso de la teoría de mezclas serie/paralelo en la simulación numérica como una herramienta para estudiar el comportamiento de la interfaz concreto-epoxi-FRP. Además, se presenta un ejemplo en el que se analizan los resultados de la simulación de un ensayo de adherencia por flexión y se contrastan con los obtenidos experimentalmente

    Semi-pilot scale-up of a continuous packed-bed bioreactor system developed for the lipase-catalyzed production of pseudo-ceramides

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    Ceramides are sphingolipid compounds that are very attractive as active components in both the pharmaceutical and the cosmetic industries. In this study, the synthesis of 1-O,3-N-diacyl 3-amino-1,2-propanediol-type pseudo-ceramides was developed at the semi-pilot scale, starting from a two-step continuous enzymatic process with immobilized Candida antarctica lipase B (Novozym¼ 435) in a packed-bed bioreactor, previously optimized at the laboratory scale. This process involved the selective N-acylation of 3-amino-1,2-propanediol (step 1), followed by the selective O-acylation of the N-acyl 3-amino-1,2-propanediol synthesized in the first step, with various fatty acids as acyl donors, to produce N,O-diacyl 3-amino-1,2-propanediol-type pseudo-ceramides (step 2). Under partially optimized operating conditions, high synthesis yields and production rates were obtained, within the ranges 76–92% and 3.7–4.6 g h−1 (step 1), or 23–36% and 1–1.4 g h−1 (step 2), respectively, depending on the fatty acids used as acyl donors. The overall synthesis yields varied from 20 to 33%: the best yield was obtained using palmitic acid and lauric acid as first and second acyl donors, respectively. Together with the high production rates also obtained with these acyl donors, this confirms that this two-step process has great potential for the production of differently functionalized 1-O,3-N-diacyl 3-amino-1,2-propanediol-type pseudo-ceramides on an industrial scale

    Graphene-based fabrics and their applications: a review

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    [EN] Graphene has emerged as a revolutionary material in different fields of science and engineering due to its extraordinary properties such as: high electron mobility, high thermal conductivity, mechanical properties, easy functionalization, etc. The field of textiles is continuously integrating new materials to provide fabrics with new functionalities, hence its incorporation on fabrics was a logical step. Its application to the field of textiles has been recently reported, which has allowed the development of textiles with different functionalities such as: antistatic, UV-protecting, electroconductive, photocatalytic, antibacterial, thermal conductivity, energy storage in flexible supercapacitors, electrodes for batteries, sensors, etc. Up to date no review has been written regarding graphene-based fabrics and their applications. The present review aims to fill the existing gap and provide perspectives into the preparation and applications of graphene-based fabrics and yarns.J. Molina wishes to thank to the Spanish Ministerio de Ciencia e Innovacion (contract CTM2011-23583) for the financial support. J. Molina is grateful to the Conselleria d'Educacio, Formacio i Ocupacio (Generalitat Valenciana) for the Programa VALi + D Postdoctoral Fellowship (APOSTD/2013/056).Molina Puerto, J. (2016). Graphene-based fabrics and their applications: a review. RSC Advances. 6:68261-68291. https://doi.org/10.1039/c6ra12365aS6826168291

    On creating mass/matter by extra dimensions in the Einstein-Gauss-Bonnet gravity

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    Kaluza-Klein (KK) black hole solutions in the Einstein-Gauss-Bonnet (EGB) gravity in DD dimensions obtained in the current series of the works by Maeda, Dadhich and Molina are examined. Interpreting their solutions, the authors claim that the mass/matter is created by the extra dimensions. To support this claim, one needs to show that such objects have classically defined masses. We calculate the mass and mass flux for 3D KK black holes in 6D EGB gravity whose properties are sufficiently physically interesting. Superpotentials for arbitrary types of perturbations on arbitrary curved backgrounds, recently obtained by the author, are used, and acceptable mass and mass flux are obtained. A possibility of considering the KK created matter as dark matter in the Universe is discussed.Comment: 15 pages, no figures, minor changes related to the Journal publication with adding two references in footnote

    Optimization and characterization of bacterial nanocellulose produced by Komagataeibacter rhaeticus K3

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    Supplementary material associated with this article can be found, in the online version, at doi:10.1016/j.carpta.2020.100022.In this work, a novel Bacterial NanoCellulose (BNC) producing strain, from Kombucha tea, was isolated and characterized. Based on 16S rRNA analysis the strain was identified as Komagataeibacter rhaeticus. Under static culture, K. rhaeticus K3 produces membranes with a relaxed structure, as observed by Scanning Electron Microscopy (SEM). The addition of 2% (v/v) ethanol to the culture media enhanced by more than 3-fold of the BNC yield. Response surface methodology (RSM) was performed with K. rhaeticus K3, using a new low cost Eucalyptus Biomass Hydrolysate (EBH). The maximum experimental BNC yield was of 5.46 g/L, obtained with the following composition: 31.4 g/L of EBH; 2.89% (v/v) of ethanol and 10.8 g/L of Yeast extract/peptone. Texture Profile Analysis (TPA) of BNC membranes obtained using Hestrin-Schramm culture (HS) medium and optimized medium from EBH showed that membranes from EBH had higher resistance to compression, higher cohesiveness and resilience.This study was supported with the funds of Institute of Technical Biochemistry, Lodz University of Technology, Lodz, Poland and from The Navigator Company through the I&D no. 21874, “Inpactus-– Produtos e Tecnologias Inovadores a partir do Eucalipto”, funded through the Fundo Europeu de Desenvolvimento Regional (FEDER) and the Programa Operacional Competitividade e Internacionalização (POCI) is greatly acknowledged. This study was also supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UID/BIO/04469/2013 unit and COMPETE 2020 (POCI01-0145-FEDER-006684) and BioTecNorte operation (NORTE-01-0145-FEDER-000004) funded by the European Regional Development Fund under the scope of Norte2020 - Programa Operacional Regional do Norte.” The authors also acknowledge the financial support of the FCT (ESF) through the grant given to Francisco A.G. Soares da Silva (SFRH/BD/146375/2019).info:eu-repo/semantics/publishedVersio

    Detection, Properties, and Frequency of Local Calcium Release from the Sarcoplasmic Reticulum in Teleost Cardiomyocytes

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    Calcium release from the sarcoplasmic reticulum (SR) plays a central role in the regulation of cardiac contraction and rhythm in mammals and humans but its role is controversial in teleosts. Since the zebrafish is an emerging model for studies of cardiovascular function and regeneration we here sought to determine if basic features of SR calcium release are phylogenetically conserved. Confocal calcium imaging was used to detect spontaneous calcium release (calcium sparks and waves) from the SR. Calcium sparks were detected in 16 of 38 trout atrial myocytes and 6 of 15 ventricular cells. The spark amplitude was 1.45±0.03 times the baseline fluorescence and the time to half maximal decay of sparks was 27±3 ms. Spark frequency was 0.88 sparks ”m−1 min−1 while calcium waves were 8.5 times less frequent. Inhibition of SR calcium uptake reduced the calcium transient (F/F0) from 1.77±0.17 to 1.12±0.18 (p = 0.002) and abolished calcium sparks and waves. Moreover, elevation of extracellular calcium from 2 to 10 mM promoted early and delayed afterdepolarizations (from 0.6±0.3 min−1 to 8.1±2.0 min−1, p = 0.001), demonstrating the ability of SR calcium release to induce afterdepolarizations in the trout heart. Calcium sparks of similar width and duration were also observed in zebrafish ventricular myocytes. In conclusion, this is the first study to consistently report calcium sparks in teleosts and demonstrate that the basic features of calcium release through the ryanodine receptor are conserved, suggesting that teleost cardiac myocytes is a relevant model to study the functional impact of abnormal SR function
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