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101.
Natalia V. Dolgova Susan Nehzati Sanjukta Choudhury Tracy C. MacDonald Nathan R. Regnier Andrew M. Crawford Olena Ponomarenko Graham N. George Ingrid J. Pickering 《Biochimica et Biophysica Acta (BBA)/General Subjects》2018,1862(11):2383-2392
Background
Selenium is an essential element with a rich and varied chemistry in living organisms. It plays a variety of important roles ranging from being essential in enzymes that are critical for redox homeostasis to acting as a deterrent for herbivory in hyperaccumulating plants. Despite its importance there are many open questions, especially related to its chemistry in situ within living organisms.Scope of review
This review discusses X-ray spectroscopy and imaging of selenium in biological samples, with an emphasis on the methods, and in particular the techniques of X-ray absorption spectroscopy (XAS) and X-ray fluorescence imaging (XFI). We discuss the experimental methods and capabilities of XAS and XFI, and review their advantages and their limitations. A perspective on future possibilities and next-generation of experiments is also provided.Major conclusions
XAS and XFI provide powerful probes of selenium chemistry, together with unique in situ capabilities. The opportunities and capabilities of the next generation of advanced X-ray spectroscopy experiments are particularly exciting.General significance
XAS and XFI provide versatile tools that are generally applicable to any element with a convenient X-ray absorption edge, suitable for investigating complex systems essentially without pre-treatment. 相似文献102.
Reinout Raijmakers Joyce JBC van Beers Mahmoud El-Azzouny Natasja FC Visser Borut Bo?i? Ger JM Pruijn Albert JR Heck 《Arthritis research & therapy》2012,14(3):R114-10
Introduction
Rheumatoid arthritis (RA) is an autoimmune disease characterized by inflammation of the joints and the presence of autoantibodies directed against proteins containing the non-standard arginine-derived amino acid citrulline. The protein fibrinogen, which has an essential role in blood clotting, is one of the most prominent citrullinated autoantigens in RA, particularly because it can be found in the inflamed tissue of affected joints. Here, we set out to analyze the presence of citrullinated endogenous peptides in the synovial fluid of RA and arthritic control patients.Methods
Endogenous peptides were isolated from the synovial fluid of RA patients and controls by filtration and solid phase extraction. The peptides were identified and quantified using high-resolution liquid chromatography-mass spectrometry.Results
Our data reveal that the synovial fluid of RA patients contains soluble endogenous peptides, derived from fibrinogen, containing significant amounts of citrulline residues and, in some cases, also phosphorylated serine. Several citrullinated peptides are found to be more abundantly present in the synovial fluid of RA patients compared to patients suffering from other inflammatory diseases affecting the joints.Conclusions
The increased presence of citrullinated peptides in RA patients points toward a possible specific role of these peptides in the immune response at the basis of the recognition of citrullinated peptides and proteins by RA patient autoantibodies. 相似文献103.
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Martijn F Schenk Jan HG Cordewener Antoine HP America Wendy PC van't Westende Marinus JM Smulders Luud JWJ Gilissen 《BMC plant biology》2009,9(1):24
Background
Bet v 1 is an important cause of hay fever in northern Europe. Bet v 1 isoforms from the European white birch (Betula pendula) have been investigated extensively, but the allergenic potency of other birch species is unknown. The presence of Bet v 1 and closely related PR-10 genes in the genome was established by amplification and sequencing of alleles from eight birch species that represent the four subgenera within the genus Betula. Q-TOF LC-MSE was applied to identify which PR-10/Bet v 1 genes are actually expressed in pollen and to determine the relative abundances of individual isoforms in the pollen proteome. 相似文献106.
(+)-Isoshinanolone was isolated from an aqueous extract of the leaves of Habropetalum dawei. After isolation of (+)-isoshinanolone, the aqueous extract of the leaves was acidified, refluxed distilled to give a new benzofuran, 2-methylbenzofuran-4-carbaldehyde. (+)-Isoshinanolone was found to have fish-stunning activity. 相似文献
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A radioimmunoassay (RIA) for polyhedron protein based on precipitation of the antibody-antigen complex by sodium acetate buffer, pH 5.0, was studied. The effects of varying assay conditions and of using [3H]acetate- or 125I-labeled antibodies were examined. The RIA could detect specific differences between the polyhedron protein from the nuclear polyhedrosis viruses of Bombyx mori and Wiseana cervinata at the level of 3 × 104 polyhedral/ml when 125I-labeled antibodies were used. This procedure could provide the basis for making serological comparisons of polyhedron proteins and for detecting viruses in samples such as soil and bird feces. 相似文献
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