9 research outputs found

    Rational design of antibodies and development of a novel method for (1–3)-β-D glucan detection as an alternative to Limulus amebocyte lysate assay

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    With advances in medicine, increasing medical interventions have increased the risk of invasive fungal disease development. (1-3)-β-D glucan (BDG) is a common fungal biomarker in serological tests. However, the scarcity of Limulus resources for BDG detection poses a challenge. This study addresses the need for an alternative to Limulus amebocyte lysate by using BDG mutant antibody for chemiluminescence detection. The wild-type BDG antibody was obtained by immunizing rabbits. An optimal V52HI/N34L Y mutant antibody, which has increased 3.7-fold of the testing efficiency compared to the wild-type antibody, was first achieved by mutating “hot-spot” residues that contribute to strong non-covalent bonds, as determined by alanine scanning and molecular dynamics simulation. The mutant was then applied to develop the magnetic particle chemiluminescence method. 574 clinical samples were tested using the developed method, with a cutoff value of 95 pg/mL set by Limulus amebocyte lysate. The receiver operating characteristic curve demonstrated an area under the curve of 0.905 (95% CI: 0.880–0.929). Chemiluminescence detected an antigen concentration of 89.98 pg/mL, exhibiting a sensitivity of 83.33% and specificity of 89.76%. In conclusion, the results showed a good agreement with Limulus amebocyte lysate and demonstrated the feasibility of using BDG mutant antibodies for invasive fungal disease diagnosis. The new method based on chemiluminescence for detecting BDG could shorten the sample-to-result time to approximately 30 min, rescue Limulus from being endangered and is resource efficient in terms of equipment and the non-use of a skilled technician

    Effect of Substituting CaO with BaO and CaO/Al<sub>2</sub>O<sub>3</sub> Ratio on the Viscosity of CaO–BaO–Al<sub>2</sub>O<sub>3</sub>–CaF<sub>2</sub>–Li<sub>2</sub>O Mold Flux System

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    The effect of substituting CaO with BaO and CaO/Al2O3 ratio on the viscosity of CaO&#8315;BaO&#8315;Al2O3&#8315;CaF2&#8315;Li2O mold flux system was studied by rotational viscosity method. The results showed that the viscosity increased with increasing BaO as a substitute for CaO, while the viscosity decreased with the increase in CaO/Al2O3 ratio. The viscous activation energy of the slags is from 92.1 kJ&#183;mol&#8722;1 to 133.4 kJ&#183;mol&#8722;1. Either the Arhenius or the Weymann&#8315;Frenkel equation can be applied to establish the viscosity prediction model. In this paper, the Weymann&#8315;Frenkel equation and a new optical basicity with regard to Al2O3 as an acidic oxide were applied to the modified NPL model for predicting the viscosity of CaO&#8315;BaO&#8315;Al2O3&#8315;CaF2&#8315;Li2O mold flux system. The estimated viscosity is in good agreement with the measured viscosity

    Structure of Solidified Films of CaO-SiO2-Na2O Based Low-Fluorine Mold Flux

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    As an essential synthetic material used in the continuous casting of steels, mold fluxes improve the surface quality of steel slabs. In this study, a CaO-SiO2-Na2O-based low-fluorine mold flux was solidified by an improved water-cooled copper probe with different temperatures of molten flux and different probe immersion times. The heat flux through solid films and the film structures were calculated and inspected, respectively. Internal cracks (formed in the glassy layer of films during solidification) were observed. The formation and evolution of those cracks contributed to the unstable heat flux density. The roughness of the surface in contact with the water-cooled copper probe formed as films were still glassy and the roughness had no causal relationship with crystallization or devitrification. Combeite with columnar and faceted dendritic shapes were the main crystal in the film

    Recyclable Strategy for the Production of High-Purity Galacto-oligosaccharides by Kluyveromyces lactis

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    A recyclable strategy for the production of high-purity (>95%) galacto-oligosaccharides (GOS) was developed using Kluyveromyces lactis in both the synthesis and purification steps. For the synthesis of GOS, ethanol-permeabilized cells (p-cells) of K. lactis were used because the enhanced permeability facilitated the mass transfer of the substrate and the release of oligosaccharide products. For the purification of GOS, non-permeabilized K. lactis cells (np-cells) were preferred as a result of their intrinsic cell membrane barrier toward GOS, which led to the selective consumption of carbohydrate. In this way, undesired glucose, galactose, and lactose in the raw GOS solution can be completely removed. This strategy is recyclable not only because of the high stability and reusability of p-cells and np-cells but also because the ethanol, which is simultaneously generated during the purification, can be reused for the preparation of p-cells. The strategy proposed in this study is a promising candidate for the efficient production of high-purity GOS

    Emerging Pt-based electrocatalysts with highly open nanoarchitectures for boosting oxygen reduction reaction

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    Developing highly efficient and stable platinum (Pt)-based electrocatalysts for oxygen reduction reaction (ORR) is the most essential step toward the commercialization of fuel cells. Highly accessible reactive surfaces play a key role in boosting ORR for superior fuel cell performance due to the adequate exposure of the active surfaces and the feasible mass transport. Herein, we begin with a brief introduction to the design principles for an effective ORR electrocatalyst, which could plausibly possess high activity and durability at the same time. Corresponding with the requirements, the recent progress of rational design based on nanoarchitecture, synthesis, and electrochemical performances of Pt -based electrocatalysts with open construction is reviewed and explained accordingly

    DataSheet_1_Rational design of antibodies and development of a novel method for (1–3)-β-D glucan detection as an alternative to Limulus amebocyte lysate assay.docx

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    With advances in medicine, increasing medical interventions have increased the risk of invasive fungal disease development. (1-3)-β-D glucan (BDG) is a common fungal biomarker in serological tests. However, the scarcity of Limulus resources for BDG detection poses a challenge. This study addresses the need for an alternative to Limulus amebocyte lysate by using BDG mutant antibody for chemiluminescence detection. The wild-type BDG antibody was obtained by immunizing rabbits. An optimal V52HI/N34L Y mutant antibody, which has increased 3.7-fold of the testing efficiency compared to the wild-type antibody, was first achieved by mutating “hot-spot” residues that contribute to strong non-covalent bonds, as determined by alanine scanning and molecular dynamics simulation. The mutant was then applied to develop the magnetic particle chemiluminescence method. 574 clinical samples were tested using the developed method, with a cutoff value of 95 pg/mL set by Limulus amebocyte lysate. The receiver operating characteristic curve demonstrated an area under the curve of 0.905 (95% CI: 0.880–0.929). Chemiluminescence detected an antigen concentration of 89.98 pg/mL, exhibiting a sensitivity of 83.33% and specificity of 89.76%. In conclusion, the results showed a good agreement with Limulus amebocyte lysate and demonstrated the feasibility of using BDG mutant antibodies for invasive fungal disease diagnosis. The new method based on chemiluminescence for detecting BDG could shorten the sample-to-result time to approximately 30 min, rescue Limulus from being endangered and is resource efficient in terms of equipment and the non-use of a skilled technician.</p
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