Search results for "init"
showing 10 items of 6629 documents
Anion Recognition by a Bioactive Diureidodecalin Anionophore: Solid-State, Solution, and Computational Studies
2018
Recent work has identified a bis-(p-nitrophenyl)ureidodecalin anion carrier as a promising candidate for biomedical applications, showing good activity for chloride transport in cells yet almost no cytotoxicity. To underpin further development of this and related compounds, a detailed structural and binding investigation is reported. Crystal structures of the transporter as five solvates confirm the diaxial positioning of urea groups while revealing a degree of conformational flexibility. Structures of complexes with Cl−, Br−, NO3 −, SO4 2− and AcO−, supported by computational studies, show how the binding site can adapt to accommodate these anions. 1H NMR binding studies revealed exception…
A circular mesh scheme for the non-orthogonal finite difference time domain method
2002
Beam forming networks (BFN) are an important component of a complex satellite antenna system because they are used to provide accurate amplitude and phase excitation to the elements of the feed network. The need for handling high power and the need for a high degree of integrability, often leads one to choose square coaxial metal lines for constructing BFNs. BFNs usually require variable power dividers such as the rat-race (or ring) couplers with constant or variable divider ratios in order to deliver a prescribed amount of power to a certain element of an antenna array to steer the beam in a desired direction. However, modeling of such circular structures in square coaxial form is not an e…
Electromagnetic Sensitivity Analysis and Shape Optimization Using Method of Moments and Automatic Differentiation
2009
Sensitivity analysis is an important part of gradient-based optimization of electromagnetic devices. We demonstrate how sensitivity analysis can be incorporated into an existing in-house method of moments solver with a relatively small amount of labor by using a technique called automatic differentiation (AD). This approach enables us to obtain (geometrical) sensitivities of the discrete solution with accuracy up to numerical precision. We compare the assembly time and memory usage of the modified and original solvers. Moreover, we optimize the shape of a dipole antenna and the dimensions of a Yagi-Uda array using the presented AD technique, traditional response level finite difference sens…
Characterization of liver cytokeratin as a major target antigen of anti-SLA antibodies.
1990
Abstract Anti-SLA antibodies characterize a newly defined subgroup of patients with autoimmune chronic active hepatitis. The aim of the present study was the immunochemical characterization of the target antigen(s) of anti-SLA antibodies. Anti-SLA-positive sera were found to contain high titres of anti-cytokeratin antibodies. In immunoblotting analyses with 100 000 × g supernatants of human liver homogenates (S-100) these sera recognized various proteins with a molecular mass of 40–60 kDa. These proteins were also recognized by monoclonal anti-cytokeratin antibodies. Two-dimensional co-electrophoresis and immunoblotting analysis of S-100 and liver cytokeratins showed that anti-SLA antibodie…
Maturation of IgG avidity to individual rubella virus structural proteins.
2001
Background: the structural proteins of rubella virus, the capsid protein C and the envelope glycoproteins E1 and E2 were produced in lepidopteran insect cells using baculovirus expression vectors. The C-terminal ends of the corresponding proteins were fused to a polyhistidine tag for easy and gentle purification by metal ion affinity chromatography. Objectives: to investigate the maturation of natural and vaccinal IgG avidity against individual authentic and recombinant rubella virus (RV) structural proteins. Study design the analysis was carried out using a modified immunoblotting technique where the purified baculovirus-expressed proteins were compared with authentic rubella virus protein…
Plant extracts as green reductants for the synthesis of silver nanoparticles: lessons from chemical synthesis.
2018
The increasing use of silver (Ag) nanoparticles (NPs) in daily-life applications, electronics, or catalysis calls for green and cost-efficient synthetic methods. Ag NPs are used especially in biomedicine because of their antibacterial, antifungal, or anticancer properties. Chemical synthesis allows tuning the particle morphology, size, and crystallinity, but requires toxic and hazardous chemicals. Bioinspired synthetic protocols have shown promise to minimize environmental impact, but biological protocols for the synthesis of Ag NPs lack control on the morphology and crystallinity. This review briefly compiles the chemical synthesis of Ag NPs and contrasts it with "green" protocols based on…
Identification of Immunoreactive Viral Proteins
2003
Several diagnostic tools are available for the identification of acute and latent viral infections. Although newly developed nucleic acid amplification methods, such as the polymerase chain reaction (PCR), have proved to be very useful diagnostic procedures, conventional methods, such as cell culture and serology, still play an important role in viral diagnostics. Despite the fact that modern serological assays, such as enzyme-linked immunosorbent assay (ELISA), are inexpensive and easy to perform, there is a strong demand to improve the performance of such systems. Most serological tests are based on poorly characterized antigens produced in infected culture cells. It has been shown, howev…
Separation of T-cell-stimulating activity from streptococcal M protein
1992
The superantigenic properties of M protein type 5 of Streptococcus pyogenes have been implicated as an important pathogenicity factor in streptococcal autoimmune diseases. Here we show that after a single purification step by affinity chromatography on immobilized albumin or fibrinogen, M protein has no mitogenic activity for T cells. We demonstrate that the superantigenicity of M proteins of type 5 and type 1 is due to contamination with the highly potent pyrogenic exotoxins of S. pyogenes in the range of 0.1 to 0.01%. These results raise a general caveat for work with these extremely active T-cell mitogens, because the mitogenicity of other streptococcal or staphylococcal proteins could b…
Embryonic neural cell adhesion molecules on human natural killer cells
1989
The neural cell adhesion molecules (NCAM) are surface glycoproteins that were first described in brain tissue. NCAM mediate adhesion in a variety of cell-cell interactions. In the present study we show that the so-called "embryonic" NCAM, i.e., the highly polysialylated forms of these proteins, are expressed on natural killer cells and some CD3+ cells in man. Homotypic binding of NCAM, believed to be of importance for cell-cell adhesion in neural tissues, appears not to be essential for NK cell-mediated killing. Yet, NCAM might be involved in NK cell migration, homing or related functions.
Preparation of Anti-protein and Anti-mannan Antisera against Fungal Cell Wall by Affinity Chromatography
1994
Abstract Iranzo, M., Marcilla, A., Elorza, M. V., Mormeneo, S., and Sentandreu, R. 1994. Preparation of anti-protein and anti-mannan antisera against fungal cell wall by affinity chromatography. Experimental Mycology 18, 159-167. A novel and easy chromatographic method has been developed for the isolation of anti-protein and anti-mannan antisera from a population of polyclonal antibodies obtained against Candida albicans and Yarrowia lipolytica cell wall mannoproteins. The technique is based on the immobilization of mannan (to be used as immunoadsorbent) by Affi-Prep H z resin after the oxidation of neighboring hydroxyl groups of the polysaccharide with sodium periodate. For Y. lipolytica p…