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Background Omega-5 gliadins are a group of highly repetitive gluten proteins in wheat flour encoded on the 1B chromosome of hexaploid wheat. These proteins are the major sensitizing allergens in a severe form of food allergy called wheat-dependent exercise-induced anaphylaxis (WDEIA). The elimination of omega-5 gliadins from wheat flour through biotechnology or breeding approaches could reduce the immunogenic potential and adverse health effects of the flour. Results A mutant line missing low-molecular weight glutenin subunits encoded at the Glu-B3 locus was selected previously from a doubled haploid population generated from two Korean wheat cultivars. Analysis of flour from the mutant line by 2-dimensional gel electrophoresis coupled with tandem mass spectrometry revealed that the omega-5 gliadins and several gamma gliadins encoded by the closely linked Gli-B1 locus were also missing as a result of a deletion of at least 5.8 Mb of chromosome 1B. Two-dimensional immunoblot analysis of flour proteins using sera from WDEIA patients showed reduced IgE reactivity in the mutant relative to the parental lines due to the absence of the major omega-5 gliadins. However, two minor proteins showed strong reactivity to patient sera in both the parental and the mutant lines and also reacted with a monoclonal antibody against omega-5 gliadin. Analysis of the two minor reactive proteins by mass spectrometry revealed that both proteins correspond to omega-5 gliadin genes encoded on chromosome 1D that were thought previously to be pseudogenes. Conclusions While breeding approaches can be used to reduce the levels of the highly immunogenic omega-5 gliadins in wheat flour, these approaches are complicated by the genetic linkage of different classes of gluten protein genes and the finding that omega-5 gliadins may be encoded on more than one chromosome. The work illustrates the importance of detailed knowledge about the genomic regions harboring the major gluten protein genes in individual wheat cultivars for future efforts aimed at reducing the immunogenic potential of wheat flour. Electronic supplementary material The online version of this article (10.1186/s12870-018-1506-z) contains supplementary material, which is available to authorized users.

RECEIVED MAY 30, 2002; ACCEPTED NOVEMBER 18, 2003Studies of iron-bearing silicate melt (ferrobasalt) þ iron metallicphase þ graphite þ hydrogen equilibria show that carbon andhydrogen solubilities in melts are important for the evolution of theupper mantle. In a series of experiments conducted at 3 7GPa and1520--- 1600 C, we have characterized the nature (oxidized vsreduced) and quantified the abundances of C- and H-compoundsdissolvediniron-bearingsilicatemelts.Experimentswerecarried outin an anvil-with-hole apparatus permitting the achievement of equalchemical potentials of H

BACKGROUND: Cereal-associated allergy is particularly considered a serious problem, because cereals are essential in our daily diet. Wheat proteins are classified into albumins, globulins and prolamins (insoluble gliadins and glutenins). OBJECTIVES: Our objectives were to study the involvement in food allergy to wheat of these different protein types by using purified fractions and to identify those binding IgE and IgG antibodies. METHODS: Sera were obtained from 28 patients with food allergy to wheat. Albumins/globulins, gliadins and glutenins were obtained by sequential extraction based on differential solubility; alpha-, beta-, gamma- and omega-gliadins and low molecular weight (LMW) and high molecular weight (HMW) glutenin subunits were purified by chromatography. IgE binding to these extracts and fractions were analysed by radioallergosorbent test (RAST), and immunoblotting; IgG binding was detected by enzyme-linked immunosorbent assay (ELISA). RESULTS: In RAST, 60% of sera were shown to have specific IgE antibodies against alpha-, beta-gliadins and LMW glutenin subunits, 55% to gamma-gliadins, 48% to omega-gliadins and 26% to HMW glutenins. Immunoblotting analysis confirmed results obtained in RAST concerning LMW and HMW glutenin subunits and showed that 67% of patients have IgE antibodies to the albumin/globulin fraction. CONCLUSION: Results obtained in the different tests showed common features and in agreement with other studies indicated the presence of numerous allergens in food allergy to wheat; alpha-, beta-, gamma- and omega-gliadins, LMW glutenin subunits and some water/salt-soluble proteins appeared as major IgE binding allergens, whereas HMW glutenins were only minor allergens. The same type of antigenic profile against gliadins and glutenins was observed with IgG antibodies. Important sequence or structural homologies between the various gliadins and LMW glutenin subunits could certainly explain similarity of IgE binding to these proteins.

A system was set up to provide direct exposure of cells cultured in vitro to radon and its decay products. Radon gas emanating from a uranium source was introduced at a measured concentration in a closed 10-m(3) exposure chamber. Cells were cultured on the microporous membrane of an insert that was floating over the culture medium in a six-well cluster plate. Plates with cells were placed in an open thermoregulated bath within the chamber. Under these conditions, cells were irradiated by direct deposition of radon and radon decay products. During exposure, all parameters, including radon gas concentrations, decay product activities, and potential alpha-particle energy concentrations, were determined by periodic air-grab samplings inside the chamber. The energy spectrum of deposited decay products was characterized. An estimation of alpha-particle flux density on the area containing cells was performed using CR-39 detector films that were exposed in cell-free wells during the cell exposure. The number of alpha-particle traversals per cell was deduced both from the mean number of CR-39 tracks per surface unit and from measurements of entire cells or nuclear surfaces. This paper describes the design of experiment, the dosimetry of radon and radon decay product, and the procedures for aerosol measurements. Our preliminary data show the usefulness of the in vitro cell culture approach to the study of the early cellular effects of radon and its decay products.

Background Gluten proteins can be modified by deamidation to enhance their solubility and technological applications. However severe allergic reactions have been reported after the consumption of food products containing deamidated gluten in subjects tolerant to wheat. This work aimed to characterize allergen profiles for these patients in comparison with those of patients allergic to wheat and identify IgE-binding epitopes. Methods Sera were obtained from 15 patients allergic to deamidated gluten (DG) and from 9 patients allergic to wheat proteins (WP). IgE-binding profiles were characterized both in ELISA and in a humanized rat basophilic leukemia (RBL) cell model. Epitopes were mapped on g and ω2-gliadin sequences by Pepscan and effect of glutamine/glutamic acid substitutions were studied. Results Compared to the heterogeneous pattern of allergens detected by IgE from patients allergic to WP, responses of patients allergic to DG were homogeneous. In ELISA, all the sera displayed IgE-binding to deamidated g and ω2-gliadins and deamidated total gliadins, frequently with high concentrations. These modified proteins induced RBL degranulation with most of the sera from DG-allergic patients. A consensus epitope was found on native g and ω2-gliadins (QPQQPFPQ); it was repeated several times in their sequences. The substitution of two or three glutamines of this epitope into glutamic acid at positions Q3 or Q4 and Q8 (QPEEPFPE) increased its recognition the best. Conclusion Allergy to DG is a separate entity from wheat allergy characterized by a homogeneous IgE response. Deamidated ω2-gliadins or the dominant IgE-binding epitope QPEEPFPE could be used as tools for the diagnosis of this new allergy. Disclosure of interest None declared.

Leaching of cement pastes shows that the properties of the surface layer are similar whether or not the cement paste contains slag. Substantial amounts of calcium, and smaller amounts of silicon, are leached out. Iron and magnesium are not released, but their content in the surface layer increases, with respect to an internal reference. Magnesium precipitates in the form of hydrotalcite, whereas the calcium of calcium silicate hydrates (CSH) is replaced by iron and dissolves out. Hydrogarnets undergo little, or no, leaching.

Background Gluten proteins can be modified by deamidation to enhance their solubility and technological applications. However, severe allergic reactions have been reported after the consumption of food products containing deamidated gluten (DG) in subjects tolerant to wheat. This work aimed to characterize allergen profiles for these patients in comparison with those of patients allergic to wheat and to identify IgE-binding epitopes. Methods Sera were obtained from 15 patients allergic to DG and from nine patients allergic to wheat proteins (WP). IgE-binding profiles were characterized both in ELISA and in a humanized rat basophilic leukaemia (RBL) cell model. Epitopes were mapped on γ- and ω2-gliadin sequences by Pepscan, and effect of glutamine/glutamic acid substitutions was studied. Results Compared to the heterogeneous pattern of allergens detected by IgE from patients allergic to WP, responses of patients allergic to DG were homogeneous. In ELISA, all the sera displayed IgE binding to deamidated γ- and ω2-gliadins and deamidated total gliadins, frequently with high concentrations. These modified proteins induced RBL degranulation with most of the sera from DG-allergic patients. A consensus epitope was found on native γ- and ω2-gliadins (QPQQPFPQ); it was repeated several times in their sequences. The substitution of two or three glutamines of this epitope into glutamic acid at positions Q3 or Q4 and Q8 (QPEEPFPE) increased its recognition the best. Conclusion Allergy to DG is a separate entity from wheat allergy. It can be evidenced by strong IgE binding to deamidated gliadins or peptides of the type QPEEPFPE.

Auto antibodies against factor VIII procoagulant activity are uncommon. Three cases are reported in three different situations: peri-partum, penicillin and idiopatic inhibitor.

Six γ-gliadin components were separated by a procedure that included ion-exchange chromatography on sulphopropyl-trisacryl M and hydrophobic interaction chromatography on phenyl sepharose CL-4B. It was possible to prepare relatively large quantities of purified gliadin components by this procedure. Each purified gliadin had a distinct mobility on Polyacrylamide gel electrophoresis (PAGE) at acid pH and on two-dimensional Polyacrylamide gel electrophoresis. They also had characteristic properties of adsorption onto the hydrophobic gel. Four components γ46, γ48 and γ50 + 51, had apparent molecular weights of 36,000 and two others, γ44 and γ45, had apparent molecular weights of 41,000 (estimated by PAGE in the presence of sodium dodecyl sulphate). These differences in molecular size were confirmed by gel filtration chromatography in the presence of 6 m guanidine hydrochloride. The amino acid composition of γ50 + 51 was more typical of α- and β-gliadins than of γ-gliadins. γ44, γ45, γ46 and γ48 had amino acid compositions typical of the γ-gliadins, such as their low tyrosine and high tryptophan contents: they migrated in two-dimensional PAGE (pH 3·2/9/·2) as spots having distinct mobilities at basic pH. A relationship was observed between retention of γ-gliadins on hydrophobic gel at basic pH and their net charges at pH 9·2.

The surface hydrophobicities of purified wheat α-, β-, γ- and ω-gliadins were investigated by hydrophobic interaction chromatography (HIC) on Octyl- and Phenyl-Sepharose CL-4B, reversed-phase high performance liquid chromatography (RP-HPLC) on octadecylsilane (TSK ODS 120 T) and apolar ligand (2- p -toluidinylnaphthalene-6-sulfonate, TNS) binding. Chromatographic methods, especially RP-HPLC, are tapid and easy to use, but they have some important limitations in that protein conformational structures during separation are unknown. Ligand binding is more time consuming but provides more fundamental information about protein hydrophobicity in solution and permits control of protein structure. Nevertheless, the results obtained using the three methods were in general agreement. On the basis of chromatographic experiments, a hydrophobicity scale for gliadins was established. These experiments also demonstrated a preference of gliadins for an aromatic ligand; this was particularly marked for ω-gliadins, suggesting that the surface hydrophobicities of α-, β-, and γ-gliadins depend on both aromatic and aliphatic amino acid side chains, whereas that of ω-gliadins depends mainly on aromatic side chains. The binding of TNS by gliadin molecules was co-operative and resulted in protein aggregation and masking of hydrophobic sites at high ligand/protein ratios. Gliadins differed in terms of the number of binding sites, with values ranging from 11 (β-gliadins) to 30 to 40 (ω-28): the binding constants also varied, being about ten times lower for ω-gliadins than for α-, β- and γ-gliadins.

Gas concentrations and isotopic compositions of water have been measured in hydrothermal waters from 13°N on the East Pacific Rise. In the most Mg-depleted samples (≌ 5 × 10 −3 moles/kg) the gas concentrations are: 3–4.5 × 10 −5 cm 3 STP/kg helium, 0.62–1.24 cm 3 STP/kg CH 4 , 10.80–16.71 × 10 −3 moles/kg CO 2 . The samples contain large quantities (95–126 cm 3 /kg) of H 2 and some carbon monoxide (0.26–0.36 cm 3 /kg) which result from reaction with the titanium sampling bottles. δ 13 C in methane and CO 2 (−16.6 to −19.5 and −4.1 to −5.5 respectively) indicate temperatures between 475 and 550°C, whereas δ 13 C CO is compatible with formation by reduction of CO 2 on Ti at 350°C close to the sampling temperature. 3 He/ 4 He are very homogeneous at (7.5 ± 0.1)R A ( 3 He/ 4 He = 1.0 × 10 −5 ) and very similar to already published data as well as CH 4 / 3 He ratios between 1.4 and 2.1 × 10 6 . 18 O and D in water show enrichments from 0.39 to 0.69‰ and from 0.62 to 1.49‰ respectively. These values correspond to W/R ratios of 0.4–7. The distinct 18 O enrichments indicate that the isotopic composition of the oceans is not completely buffered by the hydrothermal circulations. The 3 He-enthalpy relationship is discussed in terms of both hydrothermal heat flux and 3 He mantle flux.