Charge transport and contact resistance in coplanar devices based on colloidal polyaniline dispersion

Czech Academy of Sciences Publication Activity Database

Masillamani, A. M.; Peřinka, N.; Hajná, Milena; Stejskal, Jaroslav; Tondelier, D.; Bonnassieux, Y.; Vanel, J.-C.; Geffroy, B.; Mencaraglia, D.

2016-01-01

Roč. 54, č. 17 (2016), s. 1710-1716 ISSN 0887-6266 R&D Projects: GA ČR(CZ) GA13-00270S Institutional support: RVO:61389013 Keywords : charge transport * colloidal dispersion * colloids Subject RIV: JI - Composite Materials Impact factor: 2.838, year: 2016

Mesoscopic dispersion of colloidal agglomerate in a complex fluid modelled by a hybrid fluid-particle model.

Science.gov (United States)

Dzwinel, Witold; Yuen, David A

2002-03-15

The dispersion of the agglomerating fluid process involving colloids has been investigated at the mesoscale level by a discrete particle approach--the hybrid fluid-particle model (FPM). Dynamical processes occurring in the granulation of colloidal agglomerate in solvents are severely influenced by coupling between the dispersed microstructures and the global flow. On the mesoscale this coupling is further exacerbated by thermal fluctuations, particle-particle interactions between colloidal beds, and hydrodynamic interactions between colloidal beds and the solvent. Using the method of FPM, we have tackled the problem of dispersion of a colloidal slab being accelerated in a long box filled with a fluid. Our results show that the average size of the agglomerated fragments decreases with increasing shearing rate gamma, according to the power law A x gamma(k), where k is around 2. For larger values of gamma, the mean size of the agglomerate S(avg) increases slowly with gamma from the collisions between the aggregates and the longitudinal stretching induced by the flow. The proportionality constant A increases exponentially with the scaling factor of the attractive forces acting between the colloidal particles. The value of A shows a rather weak dependence on the solvent viscosity. But A increases proportionally with the scaling factor of the colloid-solvent dissipative interactions. Similar type of dependence can be found for the mixing induced by Rayleigh-Taylor instabilities involving the colloidal agglomerate and the solvent. Three types of fragmentation structures can be identified, which are called rupture, erosion, and shatter. They generate very complex structures with multiresolution character. The aggregation of colloidal beds is formed by the collisions between aggregates, which are influenced by the flow or by the cohesive forces for small dispersion energies. These results may be applied to enhance our understanding concerning the nonlinear complex

Glass-liquid-glass reentrance in mono-component colloidal dispersions

International Nuclear Information System (INIS)

Ramirez-Gonzalez, P E; Medina-Noyola, M; Vizcarra-Rendon, A; Guevara-Rodriguez, F de J

2008-01-01

The self-consistent generalized Langevin equation (SCGLE) theory of colloid dynamics is employed to describe the ergodic-non-ergodic transition in model mono-disperse colloidal dispersions whose particles interact through hard-sphere plus short-ranged attractive forces. The ergodic-non-ergodic phase diagram in the temperature-concentration state space is determined for the hard-sphere plus attractive Yukawa model within the mean spherical approximation for the static structure factor by solving a remarkably simple equation for the localization length of the colloidal particles. Finite real values of this property signals non-ergodicity and determines the non-ergodic parameters f(k) and f s (k). The resulting phase diagram for this system, which involves the existence of reentrant (repulsive and attractive) glass states, is compared with the corresponding prediction of mode coupling theory. Although both theories coincide in the general features of this phase diagram, there are also clear qualitative differences. One of the most relevant is the SCGLE prediction that the ergodic-attractive glass transition does not preempt the gas-liquid phase transition, but always intersects the corresponding spinodal curve on its high-concentration side. We also calculate the ergodic-non-ergodic phase diagram for the sticky hard-sphere model to illustrate the dependence of the predicted SCGLE dynamic phase diagram on the choice of one important constituent element of the SCGLE theory

Glass-liquid-glass reentrance in mono-component colloidal dispersions

Energy Technology Data Exchange (ETDEWEB)

Ramirez-Gonzalez, P E; Medina-Noyola, M [Instituto de Fisica ' Manuel Sandoval Vallarta' , Universidad Autonoma de San Luis Potosi, Alvaro Obregon 64, 78000 San Luis Potosi, SLP (Mexico); Vizcarra-Rendon, A [Unidad Academica de Fisica, Universidad Autonoma de Zacatecas, Paseo la Bufa y Calzada Solidaridad, 98600, Zacatecas, Zac. (Mexico); Guevara-Rodriguez, F de J [Coordinacion de IngenierIa Molecular, Instituto Mexicano del Petroleo, Eje Central Lazaro Cardenas 152, 07730 Mexico, DF (Mexico)

2008-05-21

The self-consistent generalized Langevin equation (SCGLE) theory of colloid dynamics is employed to describe the ergodic-non-ergodic transition in model mono-disperse colloidal dispersions whose particles interact through hard-sphere plus short-ranged attractive forces. The ergodic-non-ergodic phase diagram in the temperature-concentration state space is determined for the hard-sphere plus attractive Yukawa model within the mean spherical approximation for the static structure factor by solving a remarkably simple equation for the localization length of the colloidal particles. Finite real values of this property signals non-ergodicity and determines the non-ergodic parameters f(k) and f{sub s}(k). The resulting phase diagram for this system, which involves the existence of reentrant (repulsive and attractive) glass states, is compared with the corresponding prediction of mode coupling theory. Although both theories coincide in the general features of this phase diagram, there are also clear qualitative differences. One of the most relevant is the SCGLE prediction that the ergodic-attractive glass transition does not preempt the gas-liquid phase transition, but always intersects the corresponding spinodal curve on its high-concentration side. We also calculate the ergodic-non-ergodic phase diagram for the sticky hard-sphere model to illustrate the dependence of the predicted SCGLE dynamic phase diagram on the choice of one important constituent element of the SCGLE theory.

Cell-compatible conducting polyaniline films prepared in colloidal dispersion mode

Czech Academy of Sciences Publication Activity Database

Kašpárková, V.; Humpolíček, P.; Capáková, Z.; Bober, Patrycja; Stejskal, Jaroslav; Trchová, Miroslava; Rejmontová, P.; Junkar, I.; Lehocký, M.; Mozetič, M.

2017-01-01

Roč. 157, 1 September (2017), s. 309-316 ISSN 0927-7765 R&D Projects: GA ČR(CZ) GA17-05095S Institutional support: RVO:61389013 Keywords : polyaniline * conducting films * colloidal dispersions Subject RIV: CD - Macromolecular Chemistry OBOR OECD: Polymer science Impact factor: 3.887, year: 2016

Magnetorheology of colloidal dispersion containing Fe nanoparticles synthesized by the arc-plasma method

International Nuclear Information System (INIS)

Noma, Junichi; Abe, Hiroya; Kikuchi, Takehito; Furusho, Junji; Naito, Makio

2010-01-01

Spherical crystalline Fe nanoparticles, ∼100 nm in diameter, were synthesized under Ar-50% H 2 arc-plasma. These nanoparticles were dispersed in silicone oil after silane treatment on as-grown thin oxide layer (∼2 nm) to make their surfaces hydrophobic. The resulting Fe nanoparticles exhibited a high saturation magnetization of ∼190 emu/g at room temperature. The static magnetorheological behavior was measured for the colloidal dispersion (solid concentration: 15 vol%) at room temperature under magnetic flux densities of 0-0.3 T, using a parallel-plate-type commercial rheometer. The yield stress continuously increased with magnetic flux density, demonstrating the Bingham plastic behavior. Moreover, subjecting the sample to a magnetic flux density of 0.3 T increased the yield stress by ∼10 2 . Additionally, the colloidal dispersion exhibited good stability against sedimentation.

Magnetorheology of colloidal dispersion containing Fe nanoparticles synthesized by the arc-plasma method

Science.gov (United States)

Noma, Junichi; Abe, Hiroya; Kikuchi, Takehito; Furusho, Junji; Naito, Makio

2010-07-01

Spherical crystalline Fe nanoparticles, ˜100 nm in diameter, were synthesized under Ar-50% H 2 arc-plasma. These nanoparticles were dispersed in silicone oil after silane treatment on as-grown thin oxide layer (˜2 nm) to make their surfaces hydrophobic. The resulting Fe nanoparticles exhibited a high saturation magnetization of ˜190 emu/g at room temperature. The static magnetorheological behavior was measured for the colloidal dispersion (solid concentration: 15 vol%) at room temperature under magnetic flux densities of 0-0.3 T, using a parallel-plate-type commercial rheometer. The yield stress continuously increased with magnetic flux density, demonstrating the Bingham plastic behavior. Moreover, subjecting the sample to a magnetic flux density of 0.3 T increased the yield stress by ˜10 2. Additionally, the colloidal dispersion exhibited good stability against sedimentation.

Randomized clinical trial: Effective gluten degradation by Aspergillus niger-derived enzyme in a complex meal setting.

Science.gov (United States)

König, Julia; Holster, Savanne; Bruins, Maaike J; Brummer, Robert J

2017-10-12

The Aspergillus niger-derived prolyl endoprotease (AN-PEP) has previously been shown to degrade gluten in healthy subjects when added to an intragastrically infused meal. The current study investigated the efficacy of AN-PEP in a physiological meal setting. In this randomized placebo-controlled crossover study, 18 gluten-sensitive subjects consumed a porridge containing 0.5 g gluten together with two tablets either containing a high or low dose of AN-PEP, or placebo. Gastric and duodenal content was sampled over 180 minutes, and areas under the curve of gluten concentrations were calculated. The primary outcome, i.e. success rate of high dose AN-PEP defined as at least 50% gluten degradation compared to placebo in the duodenum, was achieved in 10 of 13 comparisons. In the stomach, gluten levels were reduced from 176.9 (median, interquartile range 73.5-357.8) to 22.0 (10.6-50.8, p = 0.001) in the high dose and to 25.4 μg × min/ml (16.4-43.7, p = 0.001) in the low dose. In the duodenum, gluten levels were reduced from 14.1 (8.3-124.7) in the placebo to 6.3 (3.5-19.8, p = 0.019) in the high dose and to 7.4 μg × min/ml in the low dose (3.8-12.0, p = 0.015). Thus even in a physiological meal setting, AN-PEP significantly degraded most gluten in the stomach before it entered the duodenum.

Stereolithographic processing of ceramics: Photon diffusion in colloidal dispersion

Science.gov (United States)

Garg, Rajeev

The technique of ceramic stereolithography (CSL) has been developed for fabricating near net shape ceramic objects. In stereolithography, the three-dimensional computer design file of the object is sliced into thin layers. Each layer is physically fabricated by photocuring the surface of a liquid photo-polymerizable resin bath by raster scanning an ultra-violet laser across the surface of the resin. In CSL, the liquid resin is a high concentration colloidal dispersion in a solution of ultraviolet curable polymers. The ceramic green body fabricated by ceramic stereolithography technique is subjected to the post processing steps of drying, binder burnout and sintering to form a dense ceramic object. An aqueous alumina dispersion in photocuring polymers with particle volume fraction greater than 0.5 was formulated for CSL process. Low molecular weight solution polymers were found to be best suited for formulating ceramic resins due to their inherently low viscosity and favorable interactions with the ceramic dispersant. A hydroxyapatite ceramic resin was also developed for the use in the CSL technique. A model is developed to describe the photocuring process in concentrated ceramic dispersion. The curing profile in ceramic dispersion is governed by multiple scattering from the ceramic particles and absorption by the photocuring polymers. Diffusion theory of light transport is used to model the multiple scattering and absorption phenomena. It is found that diffusive transport adequately describes the phenomena of laser pulse propagation in highly concentrated colloidal dispersions. A model was developed to describe the absorption in highly concentrated ceramic dispersion. Various complex-shaped monolithic alumina and hydroxyapatite objects were fabricated by CSL and shown to possess uniform microstructure. The mechanical properties and sintering behavior of the parts fabricated by CSL are shown to be comparable to those fabricated by other ceramic processing technique

Dynamics of polyelectrolyte adsorption and colloidal flocculation upon mixing studied using mono-dispersed polystyrene latex particles

NARCIS (Netherlands)

Feng, Lili; Cohen Stuart, Martien; Adachi, Yasuhisa

2015-01-01

The dynamic behavior of polyelectrolytes just after their encounter with the surface of bare colloidal particles is analyzed, using the flocculation properties of mono-dispersed polystyrene latex (PSL) particles. Applying a Standardized Colloid Mixing (SCM) approach, effects of ionic strength and

Arsenic speciation in the dispersible colloidal fraction of soils from a mine-impacted creek

International Nuclear Information System (INIS)

Serrano, Susana; Gomez-Gonzalez, Miguel Angel; O’Day, Peggy A.; Laborda, Francisco; Bolea, Eduardo; Garrido, Fernando

2015-01-01

Highlights: • Nanoparticle scorodite may dissolve from mine wastes and release As down-gradient. • Large fractions of total As in soils may be associated with dispersible colloids. • Up to one third of total As in soils was associated with the colloid fraction. • AsFlFFF-ICP-MS and XAS provides information on the partitioning of contaminants in colloids. - Abstract: Arsenic and iron speciation in the dispersible colloid fraction (DCF; 10–1000 nm) from an As-rich mine waste pile, sediments of a streambed that collects runoff from waste pile, the streambed subsoil, and the sediments of a downstream pond were investigated by combining asymmetrical-flow field-flow fractionation (AsFlFFF)/inductively-coupled plasma–mass spectrometry (ICP–MS), transmission electron microscopy (TEM) and X-ray absorption (XAS) spectroscopy. Calcium, Fe and As (Fe/As molar ratio ∼ 1) were the main components of the DCF from waste pile. TEM/EDS and As and Fe XAS analysis revealed the presence of nanoparticle scorodite in this same DCF, as well as Fe nanoparticles in all samples downstream of the waste pile. Arsenic and Fe XAS showed As(V) adsorbed onto nanoparticulate ferrihydrite in the DCF of downstream samples. Micro-X-ray fluorescence indicated a strong correlation between Fe and As in phyllosilicate/Fe 3+ (oxi) hydroxide aggregates from the sediment pond. Fractionation analysis showed the mean particle size of the DCF from the streambed sample to be smaller than that of the streambed subsoil and sediment ponds samples. These results show that an important and variable fraction of As may be bound to dispersible colloids that can be released from contaminated soils and transported downstream in natural systems

Arsenic speciation in the dispersible colloidal fraction of soils from a mine-impacted creek

Energy Technology Data Exchange (ETDEWEB)

Serrano, Susana [Institute of Agrochemistry and Food Technology, CSIC, Agustín Escardino 7, 46980 Paterna, Valencia (Spain); Gomez-Gonzalez, Miguel Angel [National Museum of Natural Sciences, CSIC, José Gutiérrez Abascal 2, 28006 Madrid (Spain); O’Day, Peggy A. [School of Natural Sciences,University of California, Merced, CA 95343 (United States); Laborda, Francisco; Bolea, Eduardo [Group of Analytical Spectroscopy and Sensors (GEAS), Institute of Environmental Sciences (IUCA), University of Zaragoza, Pedro Cerbuna 12, 50009 Zaragoza (Spain); Garrido, Fernando, E-mail: fernando.garrido@mncn.csic.es [National Museum of Natural Sciences, CSIC, José Gutiérrez Abascal 2, 28006 Madrid (Spain)

2015-04-09

Highlights: • Nanoparticle scorodite may dissolve from mine wastes and release As down-gradient. • Large fractions of total As in soils may be associated with dispersible colloids. • Up to one third of total As in soils was associated with the colloid fraction. • AsFlFFF-ICP-MS and XAS provides information on the partitioning of contaminants in colloids. - Abstract: Arsenic and iron speciation in the dispersible colloid fraction (DCF; 10–1000 nm) from an As-rich mine waste pile, sediments of a streambed that collects runoff from waste pile, the streambed subsoil, and the sediments of a downstream pond were investigated by combining asymmetrical-flow field-flow fractionation (AsFlFFF)/inductively-coupled plasma–mass spectrometry (ICP–MS), transmission electron microscopy (TEM) and X-ray absorption (XAS) spectroscopy. Calcium, Fe and As (Fe/As molar ratio ∼ 1) were the main components of the DCF from waste pile. TEM/EDS and As and Fe XAS analysis revealed the presence of nanoparticle scorodite in this same DCF, as well as Fe nanoparticles in all samples downstream of the waste pile. Arsenic and Fe XAS showed As(V) adsorbed onto nanoparticulate ferrihydrite in the DCF of downstream samples. Micro-X-ray fluorescence indicated a strong correlation between Fe and As in phyllosilicate/Fe{sup 3+} (oxi) hydroxide aggregates from the sediment pond. Fractionation analysis showed the mean particle size of the DCF from the streambed sample to be smaller than that of the streambed subsoil and sediment ponds samples. These results show that an important and variable fraction of As may be bound to dispersible colloids that can be released from contaminated soils and transported downstream in natural systems.

Phase behaviour of charged colloidal sphere dispersions with added polymer chains

International Nuclear Information System (INIS)

Fortini, Andrea; Dijkstra, Marjolein; Tuinier, Remco

2005-01-01

We study the stability of mixtures of highly screened repulsive charged spheres and non-adsorbing ideal polymer chains in a common solvent using free volume theory. The effective interaction between charged colloids in an aqueous salt solution is described by a screened Coulomb pair potential, which supplements the pure hard-sphere interaction. The ideal polymer chains are treated as spheres that are excluded from the colloids by a hard-core interaction, whereas the interaction between two ideal chains is set to zero. In addition, we investigate the phase behaviour of charged colloid-polymer mixtures in computer simulations, using the two-body (Asakura-Oosawa pair potential) approximation to the effective one-component Hamiltonian of the charged colloids. Both our results obtained from simulations and from free volume theory show similar trends. We find that the screened Coulomb repulsion counteracts the effect of the effective polymer-mediated attraction. For mixtures of small polymers and relatively large charged colloidal spheres, the fluid-crystal transition shifts to significantly larger polymer concentrations with increasing range of the screened Coulomb repulsion. For relatively large polymers, the effect of the screened Coulomb repulsion is weaker. The resulting fluid-fluid binodal is only slightly shifted towards larger polymer concentrations upon increasing the range of the screened Coulomb repulsion. In conclusion, our results show that the miscibility of dispersions containing charged colloids and neutral non-adsorbing polymers increases upon increasing the range of the screened Coulomb repulsion, or upon lowering the salt concentration, especially when the polymers are small compared to the colloids

Liquid-liquid and liquid-solid phase separation and flocculation for a charged colloidal dispersion

International Nuclear Information System (INIS)

Lai, S.K.; Wu, K.L.

2002-01-01

We model the intercolloidal interaction by a hard-sphere Yukawa repulsion to which is added the long-range van der Waals attraction. In comparison with the Derjaguin-Landau-Verwey-Overbeek repulsion, the Yukawa repulsion explicitly incorporates the spatial correlations between colloids and small ions. As a result, the repulsive part can be expressed analytically and has a coupling strength depending on the colloidal volume fraction. By use of this two-body potential of mean force and in conjunction with a second-order thermodynamic perturbation theory, we construct the colloidal Helmholtz free energy and use it to calculate the thermodynamic quantities, pressure and chemical potential, needed in the determination of the liquid-liquid and liquid-solid phase diagrams. We examine, in an aqueous charged colloidal dispersion, the effects of the Hamaker constant and particle size on the conformation of a stable liquid-liquid phase transition calculated with respect to the liquid-solid coexistence phases. We find that there exists a threshold Hamaker constant or particle size whose value demarcates the stable liquid-liquid coexistence phases from their metastable counterparts. Applying the same technique and using the energetic criterion, we extend our calculations to study the flocculation phenomenon in aqueous charged colloids. Here, we pay due attention to determining the loci of a stability curve stipulated for a given temperature T 0 , and obtain the parametric phase diagram of the Hamaker constant vs the coupling strength or, at given surface potential, the particle size. By imposing T 0 to be the critical temperature T c , i.e., setting k B T 0 (=k B T c ) equal to a reasonable potential barrier, we arrive at the stability curve that marks the irreversible reversible phase transition. The interesting result is that there occurs a minimum size for the colloidal particles below (above) which the colloidal dispersion is driven to an irreversible (reversible) phase

Organic-inorganic nanocomposite films made from polyurethane dispersions and colloidal silica particles

Czech Academy of Sciences Publication Activity Database

Serkis, Magdalena; Špírková, Milena; Kredatusová, Jana; Hodan, Jiří; Bureš, R.

2016-01-01

Roč. 23, č. 2 (2016), s. 157-173 ISSN 0927-6440 R&D Projects: GA ČR(CZ) GA13-06700S Institutional support: RVO:61389013 Keywords : polyurethane dispersion * colloidal silica * composites Subject RIV: CD - Macromolecular Chemistry Impact factor: 1.083, year: 2016

Hierarchical opal grating films prepared by slide coating of colloidal dispersions in binary liquid media.

Science.gov (United States)

Lee, Wonmok; Kim, Seulgi; Kim, Seulki; Kim, Jin-Ho; Lee, Hyunjung

2015-02-15

There are active researches on well ordered opal films due to their possible applications to various photonic devices. A recently developed slide coating method is capable of rapid fabrication of large area opal films from aqueous colloidal dispersion. In the current study, the slide coating of polystyrene colloidal dispersions in water/i-propanol (IPA) binary media is investigated. Under high IPA content in a dispersing medium, resulting opal film showed a deterioration of long range order, as well as a decreased film thickness due to dilution effect. From the binary liquid, the dried opal films exhibited the unprecedented topological groove patterns with varying periodic distances as a function of alcohol contents in the media. The groove patterns were consisted of the hierarchical structures of the terraced opal layers with periodic thickness variations. The origin of the groove patterns was attributed to a shear-induced periodic instability of colloidal concentration within a thin channel during the coating process which was directly converted to a groove patterns in a resulting opal film due to rapid evaporation of liquid. The groove periods of opal films were in the range of 50-500 μm, and the thickness differences between peak and valley of the groove were significantly large enough to be optically distinguishable, such that the coated films can be utilized as the optical grating film to disperse infra-red light. Utilizing a lowered hydrophilicity of water/IPA dispersant, an opal film could be successfully coated on a flexible Mylar film without significant dewetting problem. Copyright © 2014 Elsevier Inc. All rights reserved.

Antimicrobial polyethyleneimine-silver nanoparticles in a stable colloidal dispersion.

Science.gov (United States)

Lee, Hyun Ju; Lee, Se Guen; Oh, Eun Jung; Chung, Ho Yun; Han, Sang Ik; Kim, Eun Jung; Seo, Song Yi; Ghim, Han Do; Yeum, Jeong Hyun; Choi, Jin Hyun

2011-11-01

Excellent colloidal stability and antimicrobial activity are important parameters for silver nanoparticles (AgNPs) in a range of biomedical applications. In this study, polyethyleneimine (PEI)-capped silver nanoparticles (PEI-AgNPs) were synthesized in the presence of sodium borohydride (NaBH(4)) and PEI at room temperature. The PEI-AgNPs had a positive zeta potential of approximately +49 mV, and formed a stable nanocolloid against agglomeration due to electrostatic repulsion. The particle size and hydrodynamic cluster size showed significant correlations with the amount of PEI and NaBH(4). PEI-AgNPs and even PEI showed excellent antimicrobial activity against Staphylococus aureus and Klebsiella pneumoniae. The cytotoxic effects of PEI and PEI-AgNPs were confirmed by an evaluation of the cell viability. The results suggest that the amount of PEI should be minimized to the level that maintains the stability of PEI-AgNPs in a colloidal dispersion. Copyright © 2011 Elsevier B.V. All rights reserved.

Dispersions of attractive semiflexible fiberlike colloidal particles from bacterial cellulose microfibrils.

Science.gov (United States)

Kuijk, Anke; Koppert, Remco; Versluis, Peter; van Dalen, Gerard; Remijn, Caroline; Hazekamp, Johan; Nijsse, Jaap; Velikov, Krassimir P

2013-11-26

We prepared dispersions from bacterial cellulose microfibrils (CMF) of a commercial Nata de Coco source. We used an ultra-high-energy mechanical deagglomeration process that is able to disperse the CMFs from the pellicle in which they are organized in an irregular network. Because of the strong attractions between the CMFs, the dispersion remained highly heterogeneous, consisting of fiber bundles, flocs, and voids spanning tens to hundreds of micrometers depending on concentration. The size of these flocs increased with CMF concentration, the size of the bundles stayed constant, and the size of the voids decreased. The observed percolation threshold in MFC dispersions is lower than the theoretical prediction, which is accounted for by the attractive interactions in the system. Because bacterial cellulose is chemically very pure, it can be used to study the interaction of attractive and highly shape-anisotropic, semiflexible fiberlike colloidal particles.

Gluten-free but also gluten-enriched (gluten+) diet prevent diabetes in NOD mice; the gluten enigma in type 1 diabetes.

Science.gov (United States)

Funda, David P; Kaas, Anne; Tlaskalová-Hogenová, Helena; Buschard, Karsten

2008-01-01

Environmental factors such as nutrition or exposure to infections play a substantial role in the pathogenesis of type 1 diabetes (T1D). We have previously shown that gluten-free, non-purified diet largely prevented diabetes in non-obese diabetic (NOD) mice. In this study we tested hypothesis that early introduction of gluten-enriched (gluten+) diet may increase diabetes incidence in NOD mice. Standard, gluten-free, gluten+ modified Altromin diets and hydrolysed-casein-based Pregestimil diet were fed to NOD females and diabetes incidence was followed for 310 days. Insulitis score and numbers of gut mucosal lymphocytes were determined in non-diabetic animals. A significantly lower diabetes incidence (p gluten-free diet (5.9%, n = 34) and Pregestimil diet (10%, n = 30) compared to mice on the standard Altromin diet (60.6%, n = 33). Surprisingly, gluten+ diet also prevented diabetes incidence, even at the level found with the gluten-free diet (p gluten+, gluten-free, Pregestimil) diets, did that slightly later compared to those on the standard diet. Lower insulitis score compared to control mice was found in non-diabetic NOD mice on the gluten-free, and to a lesser extent also gluten+ and Pregestimil diets. No substantial differences in the number of CD3(+), TCR-gammadelta(+), and IgA(+) cells in the small intestine were documented. Gluten+ diet prevents diabetes in NOD mice at the level found with the non-purified gluten-free diet. Possible mechanisms of the enigmatic, dual effect of dietary gluten on the development of T1D are discussed. 2007 John Wiley & Sons, Ltd

Wheat gluten/montmorillonite biocomposites: Effect of pH on the mechanical properties and clay dispersion

Directory of Open Access Journals (Sweden)

E. Cortes-Trivino

2018-07-01

Full Text Available The addition of inorganic fillers into a bioplastic could increase its mechanical properties, which will be influenced strongly by the type of the clay dispersion. In this work, we have used montmorillonite nanoclays (MMT to prepare biocomposites by means of an extrusion process. We present herein the effect of the pH and the addition of montmorillonite nanoclays (MMT on the barrier and mechanical properties of wheat gluten based bioplastics. The pH of the samples was modified by adding aqueous solution of a strong acid or base (H2SO4 and NaOH. Tensile, dynamic mechanical thermal analysis (DMTA, water absorption and X-ray tests were carried out to study the influence of the above-mentioned variables on the physicochemical properties and rheological behaviour of bioplastics and biocomposites obtained. Tensile results showed that both Young’s modulus and tensile strength are higher at unmodified pH. However, the addition of MMT to an alkaline biopolymer matrix produced remarkable improvements in the rheological and mechanical properties because of a high exfoliation of the nanoclay noticeable in X-ray results. To summarise, extrusion process and the use of nanoclays present an excellent opportunity to develop wheat gluten bioplastics able to replace conventional products.

Gluten-free diet in gluten-related disorders.

Science.gov (United States)

Mulder, Chris J J; van Wanrooij, R L J; Bakker, S F; Wierdsma, N; Bouma, G

2013-01-01

A gluten-free diet (GFD) is recommended for all patients with coeliac disease (CD). The spectrum of gluten-related disorders in the early 1980s was simple: CD and dermatitis herpetiformis. In the last few years, wheat allergy, gluten ataxia and noncoeliac gluten sensitivity have become new gluten-related topics. Adherence to GFDs in CD is limited and factors influencing adherence are poorly understood. Noncoeliac gluten sensitivity has stimulated the GFD food industry not only in Australia but all over the world. This article provides an overview of GFD in daily practice. Copyright © 2013 S. Karger AG, Basel.

Stability of nano-metric colloidal dispersions of titanium: effect of surface complexation

International Nuclear Information System (INIS)

Peyre, Veronique

1996-01-01

This research thesis reports the study of the adsorption of small organic molecules at the surface of nano-particles of mineral oxides (zirconia), and of its effects on the stability of the colloidal dispersion. Adsorption has been quantified by adsorption isotherms and surface titrations. Processes and mechanisms are thus discussed with respect to pH. The influence of various protecting molecules (acetyl acetone, but also acetic acid, citric acid and diethanolamine) has been studied, and notably highlighted the role of the outer face of the complexing agent in the assessment of reactions between particles which govern the compression and re-dispersability properties of protected dispersions. This study is performed by osmotic pressure measurements and by X-ray diffusion at small angles, completed by statistical mechanics calculations [fr

Design, synthesis, and film formation of stimuli-responsive colloidal dispersions containing phospholipids

Science.gov (United States)

Lestage, David Jackson

These studies were undertaken to further understand the design of colloidal dispersions containing bio-active phospholipids (PL) as stabilizing agents and their stimuli-responsive behaviors during film formation. Methyl methacrylate (MMA) and n-butyl acrylate (nBA) dispersions were synthesized using anionic surfactants and PL, and the surface-responsiveness of coalesced films was monitored at the film-air (F-A) and film-substrate (F-S) interfaces after exposure to temperature, UV, pH, ionic strength, and enzymatic stimuli. Using spectroscopic molecular-level probes such as attenuated total reflectance (ATR) and internal reflection IR imaging (IRIRI), these studies show that structural features of PL and surfactants significantly affect stimuli-responsiveness of polymeric films. MMA/nBA homopolymer, blend, copolymer, and core-shell particle coalescence studies indicated that controlled permeability is influenced by particle composition and sodium dioctyl sulfosuccinate (SDOSS) mobility to the F-A interface is enhanced in response to temperature. Utilization of hydrogenated soybean phosphocholine (HSPC) as a co-surfactant with SDOSS resulted in bimodal p-MMA/nBA colloidal particles, and experiments showed that ionic interactions with HSPC inhibit SDOSS mobility. However, the controlled release of individual species is detected in the presence of Ca2+ ionic strength stimuli. Utilizing 1,2-bis(10,12-tricosadiynoyl)- sn-glycero-3-phosphocholine (DCPC), cocklebur-shape particle morphologies were obtained and using transmission electron microscopy (TEM), self-assembled tubules were detected at particle interfaces, but not in the presence of Ca 2+. At altered concentration levels of DCPC, surface localized ionic clusters (SLICs) composed of SDOSS and DCPC form at the F-A and F-S interfaces in response to temperature and ionic strength stimuli. Micelle formation of 1-myristoyl-2-hydroxy-sn-glycero-phosphocholine (MHPC) stabilizes unimodal p-MMA/nBA colloidal particles

Biological properties of printable polyaniline and polyaniline-silver colloidal dispersions stabilized by gelatin

Czech Academy of Sciences Publication Activity Database

Bober, Patrycja; Humpolíček, P.; Syrový, T.; Capáková, Z.; Syrová, L.; Hromádková, Jiřina; Stejskal, Jaroslav

2017-01-01

Roč. 232, October (2017), s. 52-59 ISSN 0379-6779 R&D Projects: GA ČR(CZ) GP14-05568P; GA ČR(CZ) GA17-05095S; GA TA ČR(CZ) TE01020022 Institutional support: RVO:61389013 Keywords : conducting polymer * colloidal dispersion * hybrid composite Subject RIV: CD - Macromolecular Chemistry OBOR OECD: Polymer science Impact factor: 2.435, year: 2016

Colloidal dispersions in external fields: from equilibrium to non-equilibrium

Science.gov (United States)

Lowen, Hartmut

2010-03-01

Dispersions of colloidal particles are excellent model systems of classical statistical mechanics in order to understand the principles of self-organization processes. Using an external field (e.g. electric or magnetic field) the effective interaction between the colloidal particles can be tailored and the system can be brought into non-equilibrium in a controlled way. Glass formation after an ultrafast quench in a two-dimensional superparamagnetic binary colloidal mixture [1,2] will be discussed as well as lane [3,4,5,6,7] and band [8] formation in mixtures of charged suspensions and dusty plasmas driven by an electric field. [4pt] References:[0pt] [1] L. Assoud, F. Ebert, P. Keim, R. Messina, G. Maret, H. Lowen, Phys. Rev. Letters 102, 238301 (2009). [0pt] [2] L. Assoud, F. Ebert, P. Keim, R. Messina, G. Maret, H. Lowen, J. Phys.: Condensed Matter 21, 464114 (2009). [0pt] [3] J. Dzubiella, G. P. Hoffmann, H. Lowen, Phys. Rev. E 65, 021402 (1-8) (2002). [0pt] [4] M. E. Leunissen, C. G. Christova, A. P. Hynninen, C. P. Royall, A. I. Campbell, A. Imhof, M. Dijkstra, R. van Roij, A. van Blaaderen, Nature 437, 235 (2005). [0pt] [5] M. Rex, H. Lowen, Phys. Rev. E 75, 051402 (2007). [0pt] [6] M. Rex, C. P. Royall, A. van Blaaderen, H. Lowen, Lane formation in driven colloidal mixtures: is it continuous or discontinuous?, http://arxiv.org/abs/0812.0908 [0pt] [7] K. R. Sutterlin, A. Wysocki, A. V. Ivlev, C. Rath, H. M. Thomas, M. Rubin-Zuzic, W. J. Goedheer, V. E. Fortov, A. M. Lipaev, V. I. Molotkov, O. F. Petrov, G. E. Morfill, H. Lowen, Phys. Rev. Letters 102, 085003 (2009). [0pt] [8] A. Wysocki, H. Lowen, Phys. Rev. E 79, 041408 (2009).

Non-Celiac Gluten Sensitivity among Patients Perceiving Gluten-Related Symptoms.

Science.gov (United States)

Capannolo, Annalisa; Viscido, Angelo; Barkad, Mohamed Ali; Valerii, Giorgio; Ciccone, Fabiana; Melideo, Dina; Frieri, Giuseppe; Latella, Giovanni

2015-01-01

Non-celiac gluten sensitivity (NCGS) is a recently recognized disorder, characterized by the occurrence of symptoms following gluten ingestion. It is often self-diagnosed by the patient, but should be confirmed by the response to a gluten-free diet, followed by a gluten challenge. Celiac disease (CD) and wheat allergy (WA) must first be ruled out. (1) to determine the frequency of visits performed for symptoms self-perceived as gluten-related; (2) to assess in this cohort, the proportion of patients satisfying the diagnostic criteria for NCGS. A two-year prospective study including all consecutive patients complaining of gluten-related symptoms. NCGS was diagnosed on the basis of the disappearance of the symptoms within 6 months of a gluten-free diet, followed by their reappearance with the reintroduction of gluten in the diet for 1 month. Three hundred and ninety two patients complaining of gluten-related symptoms were enrolled; 26 of these (6.63%) were affected by CD, 2 (0.51%) by WA and 27 were diagnosed with NCGS (6.88%). The remaining 337 patients (85.96%) did not experience any change of symptoms with a gluten-free diet. The PPV of the gluten-related symptom was found to be 7%. Eighty six percent of patients reporting gluten-related symptoms have neither NCGS, nor CD, nor WA. Self-perceived gluten-related symptoms are rarely indicative of the presence of NCGS. © 2015 S. Karger AG, Basel.

Properties of Gluten Intolerance: Gluten Structure, Evolution, Pathogenicity and Detoxification Capabilities

Science.gov (United States)

Balakireva, Anastasia V.; Zamyatnin, Andrey A.

2016-01-01

Theterm gluten intolerance may refer to three types of human disorders: autoimmune celiac disease (CD), allergy to wheat and non-celiac gluten sensitivity (NCGS). Gluten is a mixture of prolamin proteins present mostly in wheat, but also in barley, rye and oat. Gluten can be subdivided into three major groups: S-rich, S-poor and high molecular weight proteins. Prolamins within the groups possess similar structures and properties. All gluten proteins are evolutionarily connected and share the same ancestral origin. Gluten proteins are highly resistant to hydrolysis mediated by proteases of the human gastrointestinal tract. It results in emergence of pathogenic peptides, which cause CD and allergy in genetically predisposed people. There is a hierarchy of peptide toxicity and peptide recognition by T cells. Nowadays, there are several ways to detoxify gluten peptides: the most common is gluten-free diet (GFD), which has proved its effectiveness; prevention programs, enzymatic therapy, correction of gluten pathogenicity pathways and genetically modified grains with reduced immunotoxicity. A deep understanding of gluten intolerance underlying mechanisms and detailed knowledge of gluten properties may lead to the emergence of novel effective approaches for treatment of gluten-related disorders. PMID:27763541

Properties of Gluten Intolerance: Gluten Structure, Evolution, Pathogenicity and Detoxification Capabilities

Directory of Open Access Journals (Sweden)

Anastasia V. Balakireva

2016-10-01

Full Text Available Theterm gluten intolerance may refer to three types of human disorders: autoimmune celiac disease (CD, allergy to wheat and non-celiac gluten sensitivity (NCGS. Gluten is a mixture of prolamin proteins present mostly in wheat, but also in barley, rye and oat. Gluten can be subdivided into three major groups: S-rich, S-poor and high molecular weight proteins. Prolamins within the groups possess similar structures and properties. All gluten proteins are evolutionarily connected and share the same ancestral origin. Gluten proteins are highly resistant to hydrolysis mediated by proteases of the human gastrointestinal tract. It results in emergence of pathogenic peptides, which cause CD and allergy in genetically predisposed people. There is a hierarchy of peptide toxicity and peptide recognition by T cells. Nowadays, there are several ways to detoxify gluten peptides: the most common is gluten-free diet (GFD, which has proved its effectiveness; prevention programs, enzymatic therapy, correction of gluten pathogenicity pathways and genetically modified grains with reduced immunotoxicity. A deep understanding of gluten intolerance underlying mechanisms and detailed knowledge of gluten properties may lead to the emergence of novel effective approaches for treatment of gluten-related disorders.

Gluten Sensitivity

Science.gov (United States)

... Getting Started Diet & Nutrition Adding Fiber to Your Gluten-Free Diet Celiac Disease in the Older Adult Flours, Grains, Thickening Agents, Starches GIG’s Gluten-Free Diet and Drug Instruction Gluten-Free Grains Heart Healthy ...

Analysis of colloid transport

International Nuclear Information System (INIS)

Travis, B.J.; Nuttall, H.E.

1985-01-01

The population balance methodology is described and applied to the transport and capture of polydispersed colloids in packed columns. The transient model includes particle growth, capture, convective transport, and dispersion. We also follow the dynamic accumulation of captured colloids on the solids. The multidimensional parabolic partial differential equation was solved by a recently enhanced method of characteristics technique. This computational technique minimized numerical dispersion and is computationally very fast. The FORTRAN 77 code ran on a VAX-780 in less than a minute and also runs on an IBM-AT using the Professional FORTRAN compiler. The code was extensively tested against various simplified cases and against analytical models. The packed column experiments by Saltelli et al. were re-analyzed incorporating the experimentally reported size distribution of the colloid feed material. Colloid capture was modeled using a linear size dependent filtration function. The effects of a colloid size dependent filtration factor and various initial colloid size distributions on colloid migration and capture were investigated. Also, we followed the changing colloid size distribution as a function of position in the column. Some simple arguments are made to assess the likelihood of colloid migration at a potential NTS Yucca Mountain waste disposal site. 10 refs., 3 figs., 1 tab

Viscothermal Coupling Effects on Sound Attenuation in Concentrated Colloidal Dispersions.

Science.gov (United States)

Han, Wei

1995-11-01

This thesis describes a Unified Coupled Phase Continuum (UCPC) model to analyze sound propagation through aerosols, emulsions and suspensions in terms of frequency dependent attenuation coefficient and sound speed. Expressions for the viscous and thermal coupling coefficients explicitly account for the effects of particle size, shape factor, orientation as well as concentration and the sound frequency. The UCPC model also takes into account the intrinsic acoustic absorption within the fluid medium due to its viscosity and heat conductivity. The effective complex wave number as a function of frequency is derived. A frequency- and concentration-dependent complex Nusselt number for the interfacial thermal coupling coefficient is derived using an approximate similarity between the 'viscous skin drag' and 'heat conduction flux' associated with the discontinuous suspended phase, on the basis of a cell model. The theoretical predictions of attenuation spectra provide satisfactory agreement with reported experimental data on two concentrated suspensions (polystyrene latex and kaolin pigment), two concentrated emulsions (toluene -in-water, n-hexadecane-in-water), and two aerosols (oleic acid droplets-in-nitrogen, alumina-in-air), covering a wide range of relative magnitudes (from 10^ {-3} to 10^{3}) of thermal versus viscous contributions, for dispersed phase volume fractions as high as 50%. The relative differences between the additive result of separate viscous and thermal loss estimates and combined viscothermal absorption results are also presented. Effects of particle shape on viscous attenuation of sound in concentrated suspensions of non-spherical clay particles are studied. Attenuation spectra for 18 frequencies from 3 to 100 MHz are measured and analyzed for eleven kaolin clay slurries with solid concentrations ranging from 0.6% to 35% (w/w). A modified viscous drag coefficient that considers frequency, concentration, particle size, shape and orientation of

Adherence to a Gluten-Free Diet in Mexican Subjects with Gluten-Related Disorders: A High Prevalence of Inadvertent Gluten Intake.

Science.gov (United States)

Ramírez-Cervantes, Karen Lizzette; Romero-López, Angélica Viridiana; Núñez-Álvarez, Carlos Alberto; Uscanga-Domínguez, Luis F

2016-01-01

The rate of compliance with a gluten-free diet in patients with gluten-related disorders is unknown in most Latin American countries. To study the adherence to a gluten-free diet of Mexican individuals with celiac disease and nonceliac gluten sensitivity at the time of their first medical and nutritional consultation at a tertiary referral center. A cross-sectional study was performed. A specific questionnaire was used to gather information on demographics, clinical condition, and self-reported adherence to a gluten-free diet, and to determine strict compliance and intentional or inadvertent gluten consumption. All questionnaires were applied by a nutritionist with expertise in gluten-related disorders. Fifty-six patients with celiac disease and 24 with non-celiac gluten sensitivity were included. Overall, 46 (57.5%) subjects perceived themselves as strictly adherent; however, inadvertent gluten intake was frequent in both celiac disease and non-celiac gluten sensitivity patients (39.2 vs. 33.3%; p = 0.2). Intentional consumption was more prevalent in subjects with celiac disease (48.8 vs. 29.1%; p = 0.048) and individuals with non-celiac gluten sensitivity showed better adherence (37.5 vs. 12.5%; p = 0.035). The importance of a gluten-free diet is underestimated by Mexican patients with celiac disease. The role of a team with expertise in gluten-related disorders is essential to identify inadvertent gluten intake.

Gluten-free but also gluten-enriched (gluten+) diet prevent diabetes in NOD mice; the gluten enigma in type 1 diabetes

DEFF Research Database (Denmark)

Funda, D.P.; Kaas, A.; Tlaskalova-Hogenova, H.

2008-01-01

BACKGROUND: Environmental factors such as nutrition or exposure to infections play a substantial role in the pathogenesis of type 1 diabetes (T1D). We have previously shown that gluten-free, non-purified diet largely prevented diabetes in non-obese diabetic (NOD) mice. In this study we tested...... hypothesis that early introduction of gluten-enriched (gluten+) diet may increase diabetes incidence in NOD mice. METHODS: Standard, gluten-free, gluten+ modified Altromin diets and hydrolysed-casein-based Pregestimil diet were fed to NOD females and diabetes incidence was followed for 310 days. Insulitis...... score and numbers of gut mucosal lymphocytes were determined in non-diabetic animals. RESULTS: A significantly lower diabetes incidence (p diet (5.9%, n = 34) and Pregestimil diet (10%, n = 30) compared to mice on the standard Altromin diet (60.6%, n...

Supplementation of Reduced Gluten Barley Diet with Oral Prolyl Endopeptidase Effectively Abrogates Enteropathy-Associated Changes in Gluten-Sensitive Macaques

Directory of Open Access Journals (Sweden)

Karol Sestak

2016-06-01

Full Text Available Celiac disease (CD is an autoimmune disorder that affects approximately three million people in the United States. Furthermore, non-celiac gluten sensitivity (NCGS affects an estimated additional 6% of the population, e.g., 20 million in the U.S. The only effective treatment of CD and NCGS requires complete removal of gluten sources from the diet. While required adherence to a gluten-free diet (GFD is extremely difficult to accomplish, efforts to develop additional supportive treatments are needed. To facilitate these efforts, we developed a gluten-sensitive (GS rhesus macaque model to study the effects of novel therapies. Recently reported results from phase one of this project suggest that partial improvement—but not remission—of gluten-induced disease can be accomplished by 100-fold reduction of dietary gluten, i.e., 200 ppm—by replacement of conventional dietary sources of gluten with a mutant, reduced gluten (RG barley (lys3a-derived source. The main focus of this (phase two study was to determine if the inflammatory effects of the residual gluten in lys3a mutant barley grain could be further reduced by oral supplementation with a prolylendopeptidase (PE. Results reveal that PE supplementation of RG barley diet induces more complete immunological, histopathological and clinical remission than RG barley diet alone. The combined effects of RG barley diet and PE supplementation resulted in a further decrease of inflammatory mediators IFN-γ and TNF secretion by peripheral lymphocytes, as well as decreased plasma anti-gliadin and anti-intestinal tissue transglutaminase (TG2 antibodies, diminished active caspase production in small intestinal mucosa, and eliminated clinical diarrhea—all comparable with a gluten-free diet induced remission. In summary, the beneficial results of a combined RG barley and PE administration in GS macaques may warrant the investigation of similar synergistic approaches.

Low molecular weight compounds as effective dispersing agents in the formation of colloidal silver nanoparticles

Energy Technology Data Exchange (ETDEWEB)

Natsuki, Jun; Natsuki, Toshiaki, E-mail: natsuki@shinshu-u.ac.jp; Abe, Takao [Shinshu University, Faculty of Textile Science and Technology (Japan)

2013-03-15

A convenient method to synthesize uniform, well-dispersed colloidal silver nanoparticles is described. Aldonic acid or {alpha}-hydroxy acid compounds of low molecular weight are used instead of polymeric compounds as dispersing agents to prepare silver nanoparticles. The size, conformation, and electrical conductivity of the silver nanoparticles, and the effect and function of the dispersing agents are investigated in detail. Using these low molecular weight compounds as dispersing agents, silver nanoparticles with a diameter of 10 nm or less and high electrical conductivity can be obtained. In addition, this procedure allows silver nanoparticles to be sintered at 150 Degree-Sign C, which is lower than that required for silver nanoparticle formulation using polymeric compounds (200 Degree-Sign C). The silver nanoparticles produced by this process can be used to prepare various inks and to manufacture electronic circuits. It is found that low molecular weight compounds are more effective dispersing agents than polymeric compounds in the formation of silver nanoparticles.

Experimental Strategy to Discover Microbes with Gluten-degrading Enzyme Activities.

Science.gov (United States)

Helmerhorst, Eva J; Wei, Guoxian

2014-05-05

Gluten proteins contained in the cereals barley, rye and wheat cause an inflammatory disorder called celiac disease in genetically predisposed individuals. Certain immunogenic gluten domains are resistant to degradation by mammalian digestive enzymes. Enzymes with the ability to target such domains are potentially of clinical use. Of particular interest are gluten-degrading enzymes that would be naturally present in the human body, e.g. associated with resident microbial species. This manuscript describes a selective gluten agar approach and four enzyme activity assays, including a gliadin zymogram assay, designed for the selection and discovery of novel gluten-degrading microorganisms from human biological samples. Resident and harmless bacteria and/or their derived enzymes could potentially find novel applications in the treatment of celiac disease, in the form of a probiotic agent or as a dietary enzyme supplement.

Plasma alkylresorcinols reflect gluten intake and distinguish between gluten-rich and gluten-poor diets in a population at risk of metabolic syndrome

DEFF Research Database (Denmark)

Lind, Mads Vendelbo; Madsen, Mia Linda; Rumessen, Jüri J

2016-01-01

BACKGROUND: Many patients with celiac disease experience difficulties in adherence to a gluten-free diet. Methods for testing compliance to a gluten-free diet are costly and cumbersome. Thus, a simple biomarker of gluten intake is needed in a clinical setting and will be useful for epidemiologic...... in plasma total alkylresorcinols per 1-g increase in reported gluten intake (P gluten-free diet as well as to help investigations into the possible effects of gluten in the wider population. This trial...... 8 wk of a gluten-rich and gluten-poor diet separated by a washout period of ≥6 wk. We measured fasting plasma concentrations of alkylresorcinols to determine if they reflected differences in gluten intake as a secondary outcome of the original study. In addition, we investigated in 118 Danish adults...

Dispersion and absorption of longitudinal electro-kinetic wave in ion-implanted GaN semiconductor plasmas

Energy Technology Data Exchange (ETDEWEB)

Soni, Dilip [Government P G Madhav Science College, Ujjain (M P) (India); Sharma, Giriraj, E-mail: grsharma@gmail.com [SRJ Government Girls’ College, Neemuch (M P) (India); Saxena, Ajay [Government College, Garoth, Dist. Mandsaur (M P) (India); Jadhav, Akhilesh [Government J Yoganandam Chhattisgarh College, Raipur (C G) (India)

2015-07-31

An analytical study on propagation characteristics of longitudinal electro-kinetic (LEK) waves is presented. Based on multi-fluid model of plasma, we have derived a dispersion relation for LEK waves in colloid laden GaN semiconductor plasmas. It is assumed that ions are implanted to form colloids in the GaN sample. The colloids are continuously bombarded by the plasma particles and stick on them, but they acquire a net negative charge due to relatively higher mobility of electrons. It is found from the dispersion relation that the presence of charged colloids not only modifies the existing modes but also supports new novel modes of LEKWs. It is hoped that the study would enhance understanding on dispersion and absorption of LEKWs and help in singling out the appropriate configurations in which GaN crystal would be better suited for fabrication of microwave devices.

Navigating the gluten-free boom.

Science.gov (United States)

Gaesser, Glenn A; Angadi, Siddhartha S

2015-08-01

Gluten-free diets have gained popularity with the public at a rate greater than would be expected based on the prevalence of gluten-related disorders such celiac disease, nonceliac gluten sensitivity, and wheat allergy. This article reviews gluten-related disorders, indications for gluten-free diets, and the possible health benefits of gluten. Despite the health claims for gluten-free eating, no published experimental evidence supports weight-loss with a gluten-free diet or suggests that the general population would benefit from avoiding gluten.

Experimental studies on the inventory of cement-derived colloids in the pore water of a cementitious backfill material

International Nuclear Information System (INIS)

Wieland, E.

2001-06-01

The potential role of near-field colloids for the colloid-facilitated migration of radionuclides has stimulated investigations concerning the generation and presence of colloids in the near-field of a repository for low- and intermediate level waste (L/ILW). The highly gas permeable mortar (Nagra designation: mortar M1) is currently favoured as backfill material for the engineered barrier of the planned Swiss L/ILW repository. The cementitious backfill is considered to be a chemical environment with some potential for colloid generation. In a series of batch-style laboratory experiments the physico-chemical processes controlling the inventory of colloids in cement pore water of the backfill were assessed for chemical conditions prevailing in the initial stage of the cement degradation. In these experiments, backfill mortar M1 or quartz, respectively, which may be used as aggregate material for the backfill, were immersed in artificial cement pore water (a NaOH/KOH rich cement fluid). Colloid concentrations in the cement pore water were recorded as a function of time for different experimental settings. The results indicate that a colloid-colloid interaction process (coagulation) controlled the colloid inventory. The mass concentration of dispersed colloids was found to be typically lower than 0.02 ppm in undisturbed batch systems. An upper-bound value was estimated to be 0.1 ppm taking into account uncertainties on the measurements. To assess the potential for colloid generation in a dynamic system, colloid concentrations were determined in the pore water of a column filled with backfill mortar. The chemical conditions established in the mortar column corresponded to conditions observed in the second stage of the cement degradation (a Ca(OH) 2 - controlled cement system). In this dynamic system, the upper-bound value for the colloid mass concentration was estimated to be 0.1 ppm. Implications for radionuclide mobility were deduced taking into account the

A curated gluten protein sequence database to support development of proteomics methods for determination of gluten in gluten-free foods.

Science.gov (United States)

Bromilow, Sophie; Gethings, Lee A; Buckley, Mike; Bromley, Mike; Shewry, Peter R; Langridge, James I; Clare Mills, E N

2017-06-23

The unique physiochemical properties of wheat gluten enable a diverse range of food products to be manufactured. However, gluten triggers coeliac disease, a condition which is treated using a gluten-free diet. Analytical methods are required to confirm if foods are gluten-free, but current immunoassay-based methods can unreliable and proteomic methods offer an alternative but require comprehensive and well annotated sequence databases which are lacking for gluten. A manually a curated database (GluPro V1.0) of gluten proteins, comprising 630 discrete unique full length protein sequences has been compiled. It is representative of the different types of gliadin and glutenin components found in gluten. An in silico comparison of their coeliac toxicity was undertaken by analysing the distribution of coeliac toxic motifs. This demonstrated that whilst the α-gliadin proteins contained more toxic motifs, these were distributed across all gluten protein sub-types. Comparison of annotations observed using a discovery proteomics dataset acquired using ion mobility MS/MS showed that more reliable identifications were obtained using the GluPro V1.0 database compared to the complete reviewed Viridiplantae database. This highlights the value of a curated sequence database specifically designed to support the proteomic workflows and the development of methods to detect and quantify gluten. We have constructed the first manually curated open-source wheat gluten protein sequence database (GluPro V1.0) in a FASTA format to support the application of proteomic methods for gluten protein detection and quantification. We have also analysed the manually verified sequences to give the first comprehensive overview of the distribution of sequences able to elicit a reaction in coeliac disease, the prevalent form of gluten intolerance. Provision of this database will improve the reliability of gluten protein identification by proteomic analysis, and aid the development of targeted mass

Non-equilibrium magnetic colloidal dispersions at liquid-air interfaces: dynamic patterns, magnetic order and self-assembled swimmers

International Nuclear Information System (INIS)

Snezhko, Alexey

2011-01-01

Colloidal dispersions of interacting particles subjected to an external periodic forcing often develop nontrivial self-assembled patterns and complex collective behavior. A fundamental issue is how collective ordering in such non-equilibrium systems arises from the dynamics of discrete interacting components. In addition, from a practical viewpoint, by working in regimes far from equilibrium new self-organized structures which are generally not available through equilibrium thermodynamics can be created. In this review spontaneous self-assembly phenomena in magnetic colloidal dispersions suspended at liquid-air interfaces and driven out of equilibrium by an alternating magnetic field are presented. Experiments reveal a new type of nontrivially ordered self-assembled structures emerging in such systems in a certain range of excitation parameters. These dynamic structures emerge as a result of the competition between magnetic and hydrodynamic forces and have complex unconventional magnetic ordering. Nontrivial self-induced hydrodynamic fields accompany each out-of-equilibrium pattern. Spontaneous symmetry breaking of the self-induced surface flows leading to a formation of self-propelled microstructures has been discovered. Some features of the self-localized structures can be understood in the framework of the amplitude equation (Ginzburg-Landau type equation) for parametric waves coupled to the conservation law equation describing the evolution of the magnetic particle density and the Navier-Stokes equation for hydrodynamic flows. To understand the fundamental microscopic mechanisms governing self-assembly processes in magnetic colloidal dispersions at liquid-air interfaces a first-principle model for a non-equilibrium self-assembly is presented. The latter model allows us to capture in detail the entire process of out-of-equilibrium self-assembly in the system and reproduces most of the observed phenomenology. (topical review)

Formation and transport of radioactive colloids in porous media

International Nuclear Information System (INIS)

Chung, J.Y.; Lee, K.J.

1993-01-01

This paper deals with the effect of the presence of colloids in natural groundwater on radionuclide transport. The system considered here treats groundwater as a dispersing medium and colloid or finely divided solid material resulting from several different repository sources as a dispersed phase. Evaluation of the radionuclides adsorption on colloid, concepts of effective transport velocity and migration distance, and mathematical formulation of the filtration equation were driven, along with the case studies using typical parameter values of a conceptual radioactive waste repository and concentration on the effect of poly dispersed colloid on radionuclide transport. This paper also introduces the three phase analysis to treat the radionuclide transport more practically. When compared with the previously published experimental data, the modified filtration equation gives a satisfactory result. Results of the case studies show that the reduction of colloidal size enhances the corresponding colloid concentration when colloidal transport is only affected by diffusion phenomena. However, the three phase analysis shows that this trend can be reversed if the colloidal filtration becomes a dominant mechanism in the colloidal transport. Consequently, these results show that colloid could play a very important role in radionuclide transport under a repository environment

Structural analysis of gluten-free doughs by fractional rheological model

Science.gov (United States)

Orczykowska, Magdalena; Dziubiński, Marek; Owczarz, Piotr

2015-02-01

This study examines the effects of various components of tested gluten-free doughs, such as corn starch, amaranth flour, pea protein isolate, and cellulose in the form of plantain fibers on rheological properties of such doughs. The rheological properties of gluten-free doughs were assessed by using the rheological fractional standard linear solid model (FSLSM). Parameter analysis of the Maxwell-Wiechert fractional derivative rheological model allows to state that gluten-free doughs present a typical behavior of viscoelastic quasi-solid bodies. We obtained the contribution dependence of each component used in preparations of gluten-free doughs (either hard-gel or soft-gel structure). The complicate analysis of the mechanical structure of gluten-free dough was done by applying the FSLSM to explain quite precisely the effects of individual ingredients of the dough on its rheological properties.

Colloidal phytosterols: synthesis, characterization and bioaccessibility

NARCIS (Netherlands)

Rossi, L.; Seijen ten Hoorn, J.W.M.; Melnikov, S.M.; Velikov, K.P.

2010-01-01

We demonstrate the synthesis of phytosterol colloidal particles using a simple food grade method based on antisolvent precipitation in the presence of a non-ionic surfactant. The resulting colloidal particles have a rod-like shape with some degree of crystallinity. The colloidal dispersions display

Polymers at interfaces and in colloidal dispersions.

Science.gov (United States)

Fleer, Gerard J

2010-09-15

This review is an extended version of the Overbeek lecture 2009, given at the occasion of the 23rd Conference of ECIS (European Colloid and Interface Society) in Antalya, where I received the fifth Overbeek Gold Medal awarded by ECIS. I first summarize the basics of numerical SF-SCF: the Scheutjens-Fleer version of Self-Consistent-Field theory for inhomogeneous systems, including polymer adsorption and depletion. The conformational statistics are taken from the (non-SCF) DiMarzio-Rubin lattice model for homopolymer adsorption, which enumerates the conformational details exactly by a discrete propagator for the endpoint distribution but does not account for polymer-solvent interaction and for the volume-filling constraint. SF-SCF corrects for this by adjusting the field such that it becomes self-consistent. The model can be generalized to more complex systems: polydispersity, brushes, random and block copolymers, polyelectrolytes, branching, surfactants, micelles, membranes, vesicles, wetting, etc. On a mean-field level the results are exact; the disadvantage is that only numerical data are obtained. Extensions to excluded-volume polymers are in progress. Analytical approximations for simple systems are based upon solving the Edwards diffusion equation. This equation is the continuum variant of the lattice propagator, but ignores the finite segment size (analogous to the Poisson-Boltzmann equation without a Stern layer). By using the discrete propagator for segments next to the surface as the boundary condition in the continuum model, the finite segment size can be introduced into the continuum description, like the ion size in the Stern-Poisson-Boltzmann model. In most cases a ground-state approximation is needed to find analytical solutions. In this way realistic analytical approximations for simple cases can be found, including depletion effects that occur in mixtures of colloids plus non-adsorbing polymers. In the final part of this review I discuss a

Adverse effects of gluten ingestion and advantages of gluten withdrawal in nonceliac autoimmune disease.

Science.gov (United States)

Lerner, Aaron; Shoenfeld, Yehuda; Matthias, Torsten

2017-12-01

In light of the coincident surge in overall gluten intake and the incidence of autoimmune diseases, the possible biological adverse effects of gluten were explored. PubMed, MEDLINE, and the Cochrane Library databases were screened for reports published between 1964 and 2016 regarding the adverse effects of gluten as well as the effects of a gluten-free diet on autoimmune diseases. In vitro and in vivo studies describing gluten intake in animal models or cell lines and gluten-free diets in human autoimmune diseases were reviewed. Multiple detrimental aspects of gluten affect human health, including gluten-dependent digestive and extradigestive manifestations mediated by potentially immunological or toxic reactions that induce gastrointestinal inadequacy. Gluten affects the microbiome and increases intestinal permeability. It boosts oxidative stress and affects epigenetic behavior. It is also immunogenic, cytotoxic, and proinflammatory. Gluten intake increases apoptosis and decreases cell viability and differentiation. In certain nonceliac autoimmune diseases, gluten-free diets may help curtail the adverse effects of gluten. Additional in vivo studies are needed to unravel the puzzle of gluten effects in humans and to explore the potential beneficial effects of gluten-free diets in autoimmune diseases. © The Author(s) 2017. Published by Oxford University Press on behalf of the International Life Sciences Institute. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Lanthanide Phytanates: Liquid-Crystalline Phase Behavior, Colloidal Particle Dispersions, and Potential as Medical Imaging Agents

Energy Technology Data Exchange (ETDEWEB)

Conn, Charlotte E.; Panchagnula, Venkateswarlu; Weerawardena, Asoka; Waddington, Lynne J.; Kennedy, Danielle F.; Drummond, Calum J. (CSIRO/MHT); (CSIRO/MSE)

2010-08-23

Lanthanide salts of phytanic acid, an isoprenoid-type amphiphile, have been synthesized and characterized. Elemental analysis and FTIR spectroscopy were used to confirm the formed product and showed that three phytanate anions are complexed with one lanthanide cation. The physicochemical properties of the lanthanide phytanates were investigated using DSC, XRD, SAXS, and cross-polarized optical microscopy. Several of the hydrated salts form a liquid-crystalline hexagonal columnar mesophase at room temperature, and samarium(III) phytanate forms this phase even in the absence of water. Select lanthanide phytanates were dispersed in water, and cryo-TEM images indicate that some structure has been retained in the dispersed phase. NMR relaxivity measurements were conducted on these systems. It has been shown that a particulate dispersion of gadolinium(III) phytanate displays proton relaxivity values comparable to those of a commercial contrast agent for magnetic resonance imaging and a colloidal dispersion of europium(III) phytanate exhibits the characteristics of a fluorescence imaging agent.

Lanthanide Phytanates: Liquid-Crystalline Phase Behavior, Colloidal Particle Dispersions, and Potential as Medical Imaging Agents

International Nuclear Information System (INIS)

Conn, Charlotte E.; Panchagnula, Venkateswarlu; Weerawardena, Asoka; Waddington, Lynne J.; Kennedy, Danielle F.; Drummond, Calum J.

2010-01-01

Lanthanide salts of phytanic acid, an isoprenoid-type amphiphile, have been synthesized and characterized. Elemental analysis and FTIR spectroscopy were used to confirm the formed product and showed that three phytanate anions are complexed with one lanthanide cation. The physicochemical properties of the lanthanide phytanates were investigated using DSC, XRD, SAXS, and cross-polarized optical microscopy. Several of the hydrated salts form a liquid-crystalline hexagonal columnar mesophase at room temperature, and samarium(III) phytanate forms this phase even in the absence of water. Select lanthanide phytanates were dispersed in water, and cryo-TEM images indicate that some structure has been retained in the dispersed phase. NMR relaxivity measurements were conducted on these systems. It has been shown that a particulate dispersion of gadolinium(III) phytanate displays proton relaxivity values comparable to those of a commercial contrast agent for magnetic resonance imaging and a colloidal dispersion of europium(III) phytanate exhibits the characteristics of a fluorescence imaging agent.

Experimental studies on the inventory of cement-derived colloids in the pore water of a cementitious backfill material

Energy Technology Data Exchange (ETDEWEB)

Wieland, E

2001-06-01

The potential role of near-field colloids for the colloid-facilitated migration of radionuclides has stimulated investigations concerning the generation and presence of colloids in the near-field of a repository for low- and intermediate level waste (L/ILW). The highly gas permeable mortar (Nagra designation: mortar M1) is currently favoured as backfill material for the engineered barrier of the planned Swiss L/ILW repository. The cementitious backfill is considered to be a chemical environment with some potential for colloid generation. In a series of batch-style laboratory experiments the physico-chemical processes controlling the inventory of colloids in cement pore water of the backfill were assessed for chemical conditions prevailing in the initial stage of the cement degradation. In these experiments, backfill mortar M1 or quartz, respectively, which may be used as aggregate material for the backfill, were immersed in artificial cement pore water (a NaOH/KOH rich cement fluid). Colloid concentrations in the cement pore water were recorded as a function of time for different experimental settings. The results indicate that a colloid-colloid interaction process (coagulation) controlled the colloid inventory. The mass concentration of dispersed colloids was found to be typically lower than 0.02 ppm in undisturbed batch systems. An upper-bound value was estimated to be 0.1 ppm taking into account uncertainties on the measurements. To assess the potential for colloid generation in a dynamic system, colloid concentrations were determined in the pore water of a column filled with backfill mortar. The chemical conditions established in the mortar column corresponded to conditions observed in the second stage of the cement degradation (a Ca(OH){sub 2{sup -}} controlled cement system). In this dynamic system, the upper-bound value for the colloid mass concentration was estimated to be 0.1 ppm. Implications for radionuclide mobility were deduced taking into account the

Self-Assembly of Faceted Colloidal Particles

NARCIS (Netherlands)

Gantapara, A.P.

2015-01-01

A colloidal dispersion consists of insoluble microscopic particles that are suspended in a solvent. Typically, a colloid is a particle for which at least one of its dimension is within the size range of a nanometer to a micron. Due to collisions with much smaller solvent molecules, colloids perform

Stability studies of colloidal silica dispersions in binary solvent mixtures

International Nuclear Information System (INIS)

Bean, Keith Howard

1997-01-01

A series of monodispersed colloidal silica dispersions, of varying radii, has been prepared. These particles are hydrophilic in nature due to the presence of surface silanol groups. Some of the particles have been rendered hydrophobic by terminally grafting n-alkyl (C 18 ) chains to the surface. The stability of dispersions of these various particles has been studied in binary mixtures of liquids, namely (i) ethanol and cyclohexane, and (ii) benzene and n-heptane. The ethanol - cyclohexane systems have been studied using a variety of techniques. Adsorption excess isotherms have been established and electrophoretic mobility measurements have been made. The predicted stability of the dispersions from D.V.L.O. calculations is compared to the observed stability. The hydrophilic silica particles behave as predicted by the calculations, with the zeta potential decreasing and the van der Waals attraction increasing with increasing cyclohexane concentration. The hydrophobic particles behave differently than expected, and the stability as a function of solvent mixture composition does not show a uniform trend. The effect of varying the coverage of C 18 chains on the surface and the effect of trace water in the systems has also been investigated. Organophilic silica dispersions in benzene - n-heptane solvent mixtures show weak aggregation and phase separation into a diffuse 'gas-like' phase and a more concentrated 'liquid-like' phase, analogous to molecular condensation processes. Calculations of the van der Waals potential as a function of solvent mixture composition show good agreement with the observed stability. Determination of the number of particles in each phase at equilibrium allows the energy of flocculation to be determined using a simple thermodynamic relationship. Finally, the addition of an AB block copolymer to organophilic silica particles in benzene n-heptane solvent mixtures has been shown to have a marked effect on the dispersion stability. This stability

Gluten Intolerance Group

Science.gov (United States)

... Intolerance Group (GIG), the industry leader in the certification of gluten-free products and food services, announced today that a wide ... of gluten-free products. One of the top certification programs in the world, GFCO inspects products and manufacturing facilities for gluten, in an effort ...

A non-local structural derivative model for characterization of ultraslow diffusion in dense colloids

Science.gov (United States)

Liang, Yingjie; Chen, Wen

2018-03-01

Ultraslow diffusion has been observed in numerous complicated systems. Its mean squared displacement (MSD) is not a power law function of time, but instead a logarithmic function, and in some cases grows even more slowly than the logarithmic rate. The distributed-order fractional diffusion equation model simply does not work for the general ultraslow diffusion. Recent study has used the local structural derivative to describe ultraslow diffusion dynamics by using the inverse Mittag-Leffler function as the structural function, in which the MSD is a function of inverse Mittag-Leffler function. In this study, a new stretched logarithmic diffusion law and its underlying non-local structural derivative diffusion model are proposed to characterize the ultraslow diffusion in aging dense colloidal glass at both the short and long waiting times. It is observed that the aging dynamics of dense colloids is a class of the stretched logarithmic ultraslow diffusion processes. Compared with the power, the logarithmic, and the inverse Mittag-Leffler diffusion laws, the stretched logarithmic diffusion law has better precision in fitting the MSD of the colloidal particles at high densities. The corresponding non-local structural derivative diffusion equation manifests clear physical mechanism, and its structural function is equivalent to the first-order derivative of the MSD.

Clustering and self-assembly in colloidal systems

NARCIS (Netherlands)

Smallenburg, F.

2012-01-01

A colloidal dispersion consists of small particles called colloids, typically tens of nanometers to a few micrometers in size, suspended in a solvent. Due to collisions with the much smaller particles in the solvent, colloids perform Brownian motion: randomly directed movements that cause the

Superhydrophilic graphite surfaces and water-dispersible graphite colloids by electrochemical exfoliation

Energy Technology Data Exchange (ETDEWEB)

Li, Yueh-Feng [Department of Chemical and Materials Engineering, National Central University, Jhongli, 320 Taiwan (China); Chen, Shih-Ming; Lai, Wei-Hao [Materials and Chemical Research Laboratories, Industrial Technology Research Institute, Chutung, Hsinchu, 31040 Taiwan (China); Sheng, Yu-Jane [Department of Chemical Engineering, National Taiwan University, Taipei, 106 Taiwan (China); Tsao, Heng-Kwong [Department of Chemical and Materials Engineering, Department of Physics, National Central University, Jhongli, 320 Taiwan (China)

2013-08-14

Superhydrophilic graphite surfaces and water-dispersible graphite colloids are obtained by electrochemical exfoliation with hydrophobic graphite electrodes. Such counterintuitive characteristics are caused by partial oxidation and investigated by examining both graphite electrodes and exfoliated particles after electrolysis. The extent of surface oxidation can be explored through contact angle measurement, scanning electron microscope, electrical sheet resistance, x-ray photoelectron spectroscopy, zeta-potential analyzer, thermogravimetric analysis, UV-visible, and Raman spectroscopy. The degree of wettability of the graphite anode can be altered by the electrolytic current and time. The water contact angle declines generally with increasing the electrolytic current or time. After a sufficient time, the graphite anode becomes superhydrophilic and its hydrophobicity can be recovered by peeling with adhesive tape. This consequence reveals that the anodic graphite is oxidized by oxygen bubbles but the oxidation just occurs at the outer layers of the graphite sheet. Moreover, the characteristics of oxidation revealed by UV peak shift, peak ratio between D and G bands, and negative zeta-potential indicate the presence of graphite oxide on the outer shell of the exfoliated colloids. However, thermogravimetric analysis for the extent of decomposition of oxygen functional groups verifies that the amount of oxygen groups is significantly less than that of graphite oxide prepared via Hummer method. The structure of this partially oxidized graphite may consist of a graphite core covered with an oxidized shell. The properties of the exfoliated colloids are also influenced by pH of the electrolytic solution. As pH is increased, the extent of oxidation descends and the thickness of oxidized shell decreases. Those results reveal that the degree of oxidation of exfoliated nanoparticles can be manipulated simply by controlling pH.

Is it gluten-free? Relationship between self-reported gluten-free diet adherence and knowledge of gluten content of foods.

Science.gov (United States)

Silvester, Jocelyn A; Weiten, Dayna; Graff, Lesley A; Walker, John R; Duerksen, Donald R

2016-01-01

To assess the relationship between self-reported adherence to a gluten-free diet (GFD) and the ability to determine correctly the appropriateness of particular foods in a GFD. Persons with celiac disease were recruited through clinics and support groups. Participants completed a questionnaire with items related to GFD information sources, gluten content of 17 common foods (food to avoid, food allowed, and food to question), GFD adherence, and demographic characteristics. Diagnosis was self-reported. The 82 respondents (88% female) had a median of 6 y GFD experience. Most (55%) reported strict adherence, 18% reported intentional gluten consumption and 21% acknowledged rare unintentional gluten consumption. Cookbooks, advocacy groups, and print media were the most commonly used GFD information sources (85-92%). No participant identified correctly the gluten content of all 17 foods; only 30% identified at least 14 foods correctly. The median score on the Gluten-Free Diet Knowledge Scale (GFD-KS) was 11.5 (interquartile ratio, 10-13). One in five incorrect responses put the respondent at risk of consuming gluten. GFD-KS scores did not correlate with self-reported adherence or GFD duration. Patient advocacy group members scored significantly higher on the GFD-KS than non-members (12.3 versus 10.6; P gluten ingestion overestimate GFD adherence. Individuals who believe they are following a GFD are not readily able to correctly identify foods that are GF, which suggests ongoing gluten consumption may be occurring, even among patients who believe they are "strictly" adherent. The role of patient advocacy groups and education to improve outcomes through improved adherence to a GFD requires further research. Copyright © 2016 Elsevier Inc. All rights reserved.

Symptomatic suspected gluten exposure is common among patients with coeliac disease on a gluten-free diet.

Science.gov (United States)

Silvester, J A; Graff, L A; Rigaux, L; Walker, J R; Duerksen, D R

2016-09-01

A gluten-free diet is the only recommended treatment for coeliac disease. To determine the prevalence and characteristics of reactions to gluten among persons with coeliac disease on a gluten-free diet. Adults with biopsy proven, newly diagnosed coeliac disease were prospectively enrolled. A survey related to diet adherence and reactions to gluten was completed at study entry and 6 months. The Coeliac Symptom Index, Coeliac Diet Assessment Tool (CDAT) and Gluten-Free Eating Assessment Tool (GF-EAT) were used to measure coeliac disease symptoms and gluten-free diet adherence. Of the 105 participants, 91% reported gluten exposure gluten was reported by 66%. Gluten consumption was unsuspected until a reaction occurred (63%) or resulted from problems ordering in a restaurant (29%). The amount of gluten consumed ranged from cross-contact (30%) to a major ingredient (10%). Median time to symptom onset was 1 h (range 10 min to 48 h), and median symptom duration was 24 h (range 1 h to 8 days). Common symptoms included abdominal pain (80%), diarrhoea (52%), fatigue (33%), headache (30%) and irritability (29%). Reactions to suspected gluten exposure are common among patients with coeliac disease on a gluten-free diet. Eating at restaurants and other peoples' homes remain a risk for unintentional gluten exposure. When following individuals with coeliac disease, clinicians should include questions regarding reactions to gluten as part of their assessment of gluten-free diet adherence. © 2016 John Wiley & Sons Ltd.

Density fluctuation in a screened Coulombic colloid dispersion: comparison of the liquid and cubic phases of lipid A-diphosphate

International Nuclear Information System (INIS)

Brown, Helen; Ross, D. Keith; Paradies, Henrich H.

2004-01-01

Light-, small-angle X-ray and neutron scattering measurements of the dynamic structure factor S(Q,t) of strong interacting dispersions of lipid A-diphosphate were recorded and analysed applying existing models of liquid state theory. Lipid A-diphosphate ordering was observed at low volume fractions (phi=2.2x10 -4 ) and at very low ionic strength (I=10 -5 M). Upon increasing the particle number density of lipid A-diphosphate a transformation of the lattices of the colloidal crystals from a BCC lattice (a=36.20 nm) to a FCC lattice (a=57.30 nm) occurred. This strongly suggests a similarity in the preformed liquid structure and the cubic colloidal phase. The fit of both S eff (Q) and the principle peak I p (Q) with the effective particle charge supports of the main conclusions drawn from the SANS experiments and the liquid state theory indicating the presence of long-range order for the dispersions of lipid A-diphosphate

Gluten-free but also gluten-enriched (gluten+) diet prevent diabetes in NOD mice; the gluten enigma in type 1 diabetes

Czech Academy of Sciences Publication Activity Database

Funda, David P.; Kaas, A.; Tlaskalová, Helena; Buschard, K.

2007-01-01

Roč. 24, - (2007), s. 59-63 ISSN 1520-7552 R&D Projects: GA AV ČR IAA5020405; GA ČR GA303/06/1329 Institutional research plan: CEZ:AV0Z50200510 Keywords : gluten * gluten -free * type 1 diabetes Subject RIV: EE - Microbiology, Virology Impact factor: 3.087, year: 2007

Evaluation of gluten in gluten-free-labeled foods and assessment of exposure level to gluten among celiac patients in Lebanon.

Science.gov (United States)

Hassan, Hussein; Elaridi, Jomana; Bassil, Maya

2017-11-01

The aim of the study was to evaluate gluten contamination in all the gluten-free (GF)-labeled food products sold in Lebanon. Over a 2-year period, a total of 173 food samples collected from 135 brand names were analyzed. Gluten contamination was detected in 33 of 173 (19%) samples, and its content ranged between 2.5 and >80 mg kg -1 . In 10 of the 173 samples (6%), the quantity of gluten exceeded the upper limit of 20 mg kg -1 . Out of the 10 contaminated products, eight (80%) were locally manufactured. Among these 10 products, eight (80%) were wheat-starch-based foods. Of the 40 brand names tested twice in 2014 and 2015, 15 (38%) showed significantly (p < .05) different gluten content between the 2 years. Using a food frequency questionnaire, exposure level to gluten through the contaminated products was evaluated among 15 celiac patients. Two patients reported consuming these products more than twice per week.

Avoiding Gluten Cross-Contamination

Science.gov (United States)

... Meal Options for Kids with Food Allergies The Gluten-Free Diet Watch and Learn Videos View More What a ... on This Topic Does My Child Need a Gluten Free Diet Gluten is a protein found in certain grains ...

Effect of gluten free diet on immune response to gliadin in patients with non-celiac gluten sensitivity.

Science.gov (United States)

Caio, Giacomo; Volta, Umberto; Tovoli, Francesco; De Giorgio, Roberto

2014-02-13

Non-celiac gluten sensitivity is a syndrome characterized by gastrointestinal and extra-intestinal symptoms occurring in a few hours/days after gluten and/or other wheat protein ingestion and rapidly improving after exclusion of potential dietary triggers. There are no established laboratory markers for non-celiac gluten sensitivity, although a high prevalence of first generation anti-gliadin antibodies of IgG class has been reported in this condition. This study was designed to characterize the effect of the gluten-free diet on anti-gliadin antibodies of IgG class in patients with non-celiac gluten sensitivity. Anti-gliadin antibodies of both IgG and IgA classes were assayed by ELISA in 44 non-celiac gluten sensitivity and 40 celiac disease patients after 6 months of gluten-free diet. The majority of non-celiac gluten sensitivity patients (93.2%) showed the disappearance of anti-gliadin antibodies of IgG class after 6 months of gluten-free diet; in contrast, 16/40 (40%) of celiac patients displayed the persistence of these antibodies after gluten withdrawal. In non-celiac gluten sensitivity patients anti-gliadin antibodies IgG persistence after gluten withdrawal was significantly correlated with the low compliance to gluten-free diet and a mild clinical response. Anti-gliadin antibodies of the IgG class disappear in patients with non-celiac gluten sensitivity reflecting a strict compliance to the gluten-free diet and a good clinical response to gluten withdrawal.

Fructan, Rather Than Gluten, Induces Symptoms in Patients With Self-Reported Non-Celiac Gluten Sensitivity.

Science.gov (United States)

Skodje, Gry I; Sarna, Vikas K; Minelle, Ingunn H; Rolfsen, Kjersti L; Muir, Jane G; Gibson, Peter R; Veierød, Marit B; Henriksen, Christine; Lundin, Knut E A

2018-02-01

Non-celiac gluten sensitivity is characterized by symptom improvement after gluten withdrawal in absence of celiac disease. The mechanisms of non-celiac gluten sensitivity are unclear, and there are no biomarkers for this disorder. Foods with gluten often contain fructans, a type of fermentable oligo-, di-, monosaccharides and polyols. We aimed to investigate the effect of gluten and fructans separately in individuals with self-reported gluten sensitivity. We performed a double-blind crossover challenge of 59 individuals on a self-instituted gluten-free diet, for whom celiac disease had been excluded. The study was performed at Oslo University Hospital in Norway from October 2014 through May 2016. Participants were randomly assigned to groups placed on diets containing gluten (5.7 g), fructans (2.1 g), or placebo, concealed in muesli bars, for 7 days. Following a minimum 7-day washout period (until the symptoms induced by the previous challenge were resolved), participants crossed over into a different group, until they completed all 3 challenges (gluten, fructan, and placebo). Symptoms were measured by Gastrointestinal Symptom Rating Scale Irritable Bowel Syndrome (GSRS-IBS) version. A linear mixed model for analysis was used. Overall GSRS-IBS scores differed significantly during gluten, fructan, and placebo challenges; mean values were 33.1 ± 13.3, 38.6 ± 12.3, and 34.3 ± 13.9, respectively (P = .04). Mean scores for GSRS-IBS bloating were 9.3 ± 3.5, 11.6 ± 3.5, and 10.1 ± 3.7, respectively, during the gluten, fructan, and placebo challenges (P = .004). The overall GSRS-IBS score for participants consuming fructans was significantly higher than for participants consuming gluten (P = .049), as was the GSRS bloating score (P = .003). Thirteen participants had the highest overall GSRS-IBS score after consuming gluten, 24 had the highest score after consuming fructan, and 22 had the highest score after consuming placebo. There was no difference in GSRS

Starch facilitates enzymatic wheat gluten hydrolysis

NARCIS (Netherlands)

Hardt, N.A.; Boom, R.M.; Goot, van der A.J.

2015-01-01

Wheat gluten can be hydrolyzed by either using (vital) wheat gluten or directly from wheat flour. This study investigates the influence of the presence of starch, the main component of wheat, on enzymatic wheat gluten hydrolysis. Wheat gluten present in wheat flour (WFG) and vital wheat gluten (VWG)

Treatment of both native and deamidated gluten peptides with an endo-peptidase from Aspergillus niger prevents stimulation of gut-derived gluten-reactive T cells from either children or adults with celiac disease

DEFF Research Database (Denmark)

Toft-Hansen, Henrik; Rasmussen, Karina Søndergård; Nielsen, Anne Staal

2014-01-01

the proliferative response by a gluten-specific CD4+ T cell clone and seven gluten-reactive T cell lines to protease-digested gluten peptides. A proline-specific endo-peptidase from Aspergillus niger (AnP2), was particularly efficient at diminishing proliferation after stimulation with cleaved antigen, and could...

Rheology and microstructure of gluten and soya-based o/w emulsions

Energy Technology Data Exchange (ETDEWEB)

Bengoechea, Carlos; Cordobes, Felipe; Guerrero, Antonio [Universidad de Sevilla, Departamento de Ingenieria Quimica, Sevilla (Spain)

2006-10-15

Highly concentrated oil-in-water (o/w) emulsion stabilised by means of gluten and soya protein isolate (SPI) at low pH have been characterized by means of linear dynamic viscoelasticity and droplet size distribution analysis (DSD). The microstructure of these emulsions has been characterized at a colloidal level by using confocal laser scanning microscopy (CLSM) and light microscopy (LM). These emulsions always exhibited a behaviour characteristic of highly flocculated emulsions with a mechanical spectrum showing a well-developed plateau region. DSD results generally showed log normal bimodal profiles. Microstructure images revealed occurrence of a close packing of droplets with a broad distribution of sizes participating in the formation of a three dimensional flocculated network. The Mason model of elasticity of compressed emulsions has been used to correlate viscoelastic and microstructural parameters giving adequate fitting but underestimating the elastic properties obtained for the highest concentration of gluten. These deviations may be explained in terms of an enhancement of the elastic network formed in the aqueous phase in which the glutenin fraction must play an important role. (orig.)

Gluten intake and gluten-free diet in the Netherlands

NARCIS (Netherlands)

Hopman, Geertruida Dorothea

2008-01-01

Celiac disease is an intolerance to dietary gluten in genetically predisposed individuals, leading to alterations of the small bowel mucosa. The treatment consists of a life-long, gluten-free diet. The aims of this thesis were to measure some of the environmental factors considered to play a role

Effective sorption of atrazine by biochar colloids and residues derived from different pyrolysis temperatures.

Science.gov (United States)

Yang, Fan; Gao, Yan; Sun, Lili; Zhang, Shuaishuai; Li, Jiaojiao; Zhang, Ying

2018-04-26

Biochar has attracted much attention, which owns many environmental and agronomic benefits, including carbon sequestration, improvement of soil quality, and immobilization of environmental contaminants. Biochar has been also investigated as an effective sorbent in recent publications. Generally, biochar particles can be divided into colloids and residues according to particle sizes, while understanding of adsorption capacities towards organic pollutants in each section is largely unknown, representing a critical knowledge gap in evaluations on the effectiveness of biochar for water treatment application. Scanning electron microscopy (SEM) images, X-ray diffraction (XRD), Raman spectra, Fourier-transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), and Brunauer-Emmett-Teller (BET) method are used to examine the structures and surface properties of biochar colloids and residues derived from corn straws prepared at different pyrolysis temperatures. Also, their roles in atrazine (a typical organic pollutant) removal are investigated by batch adsorption experiments and fitted by different kinetic and thermodynamic models, respectively. The adsorption capacities of biochar colloids are much more than those of residues, resulting from the colloids containing abundant oxygen functional groups and mineral substances, and the adsorption capacities of biochar colloids and residues increase with the increase of pyrolysis temperatures. The highest adsorption performance of 139.33 mg g -1 can be obtained in biochar colloids prepared at 700 °C, suggesting the important functions of biochar colloids in the application of atrazine removal by biochar.

Experimental and Theoretical Investigations on Agglomeration of Magnetic Colloidal Particles in Magnetic Fluids

Science.gov (United States)

Taketomi, Susamu; Takahashi, Hiromasa; Inaba, Nobuyuki; Miyajima, Hideki

1991-05-01

Macro-clusters formation of the magnetic colloidal particles in magnetic fluids is investigated. Experiments of an optical microscope observation of the macro-clusters formation and of anomalous light scattering by the magnetic fluid are reported. Looking upon the anomalous light scattering of the magnetic fluid as a kind of critical opalescence and using Debye’s opalescence theory, we derive a thermodynamical instability theory of the colloidal particles’ dispersion. Relations among the instability theory of Cebers, that of Sano and Doi, and ours are discussed. An interaction energy among the colloidal particles is evaluated from the light scattering experiment. Similarities among the macro-cluster formation, spinodal decomposition of precipitation-type magnetic alloys, and flux-line lattice formation in type-II superconductors are discussed.

Colloidal dispersions of maghemite nanoparticles produced by laser pyrolysis with application as NMR contrast agents

Energy Technology Data Exchange (ETDEWEB)

Veintemillas-Verdaguer, Sabino [Instituto de Ciencia de Materiales de Madrid, CSIC, Cantoblanco, 28049 Madrid (Spain); Morales, Maria del Puerto [Instituto de Ciencia de Materiales de Madrid, CSIC, Cantoblanco, 28049 Madrid (Spain); Bomati-Miguel, Oscar [Instituto de Ciencia de Materiales de Madrid, CSIC, Cantoblanco, 28049 Madrid (Spain); Bautista, Carmen [Instituto de Ciencia de Materiales de Madrid, CSIC, Cantoblanco, 28049 Madrid (Spain); Zhao, Xinqing [Instituto de Ciencia de Materiales de Madrid, CSIC, Cantoblanco, 28049 Madrid (Spain); Bonville, Pierre [CEA, CE Saclay, DSM/DRECAM/SPEC, 91191 Gif-Sur-Yvette (France); Alejo, Rigoberto Perez de [Universidad Complutense de Madrid, Unidad de RMN, Paseo Juan XXIII, 1, 28040 Madrid (Spain); Ruiz-Cabello, Jesus [Universidad Complutense de Madrid, Unidad de RMN, Paseo Juan XXIII, 1, 28040 Madrid (Spain); Santos, Martin [Hospital Universitario Puerta de Hierro, Servicio de Cirugia Experimental. C/San Martin de Porres 4, 28035 Madrid (Spain); Tendillo-Cortijo, Francisco J [Hospital Universitario Puerta de Hierro, Servicio de Cirugia Experimental. C/San Martin de Porres 4, 28035 Madrid (Spain); Ferreiros, Joaquin [Hospital Clinico de Madrid ' San Carlos' , Ciudad Universitaria, 28040 Madrid (Spain)

2004-08-07

Biocompatible magnetic dispersions have been prepared from {gamma}-Fe{sub 2}O{sub 3} nanoparticles (5 nm) synthesized by continuous laser pyrolysis of Fe(CO){sub 5} vapours. The feasibility of using these dispersions as magnetic resonance imaging (MRI) contrast agents has been analysed in terms of chemical structure, magnetic properties, {sup 1}H NMR relaxation times and biokinetics. The magnetic nanoparticles were dispersed in a strong alkaline solution in the presence of dextran, yielding stable colloids in a single step. The dispersions consist of particle-aggregates 25 nm in diameter measured using transmission electron microscope and a hydrodynamic diameter of 42 nm measured using photon correlation spectroscopy. The magnetic and relaxometric properties of the dispersions were of the same order of magnitude as those of commercial contrast agents produced using coprecipitation. However, these dispersions, when injected intravenously in rats at standard doses showed a mono-exponential blood clearance instead of a biexponential one, with a blood half-life of 7 {+-} 1 min. Furthermore, an important enhancement of the image contrast was observed after the injection, mainly located at the liver and the spleen of the rat. In conclusion, the laser pyrolysis technique seems to be a good alternative to the coprecipitation method for producing MRI contrast agents, with the advantage of being a continuous synthesis method that leads to very uniform particles capable of being dispersed and therefore transformed in a biocompatible magnetic liquid.

Prevalence of Self-Reported Gluten-Related Disorders and Adherence to a Gluten-Free Diet in Salvadoran Adult Population.

Science.gov (United States)

Ontiveros, Noé; Rodríguez-Bellegarrigue, Cecilia Ivonne; Galicia-Rodríguez, Gerardo; Vergara-Jiménez, Marcela de Jesús; Zepeda-Gómez, Elia María; Arámburo-Galvez, Jesús Gilberto; Gracia-Valenzuela, Martina Hilda; Cabrera-Chávez, Francisco

2018-04-18

Gluten-related disorders are not considered of relevance at public health level in Central America. The prevalence of gluten-related disorders, and adherence to a gluten-free diet, remain unknown in the Central American region. We conducted a cross-sectional survey of the Central American population from San Salvador, El Salvador, to estimate the prevalence rates of self-reported gluten-related disorders and adherence to a gluten-free diet. 1326 individuals were surveyed. Self-reported prevalence rates were (95% Confidence Interval): gluten sensitivity 3.1% (2.3–4.2); physician-diagnosed celiac disease 0.15% (0.04–0.5); wheat allergy 0.75% (0.4–1.3); non-celiac gluten sensitivity 0.98% (0.5–1.6). The prevalence rate of adherence to a gluten-free diet was 7.0% (5.7–8.5). Seven self-reported physician diagnosed gluten-sensitive cases informed the co-existence of non-celiac gluten sensitivity with celiac disease and/or wheat allergy. Among the non-self-reported gluten sensitivity individuals following a gluten-free diet, 50% reported that they were seeing a health professional for gluten-free dietary advice. Gluten sensitivity is commonly reported in Salvadoran population, but some health professionals acknowledge the coexistence of wheat allergy, celiac disease, and non-celiac gluten sensitivity. Among studies at population level, the prevalence of adherence to a gluten-free diet in Salvadoran population is the highest reported until now. However, just a few of the gluten-free diet followers were doing it for health-related benefits; the others reported weight control and the perception that the diet is healthier as the main motivation for adopting such a diet.

The human digestive tract has proteases capable of gluten hydrolysis

Directory of Open Access Journals (Sweden)

Sergio Gutiérrez

2017-07-01

Conclusion: The digestive tracts of patients with CD and healthy subjects have enzymatic machinery needed for gluten degradation. Patients with CD showed more gluten hydrolysis than did healthy individuals, although, in both cases, a fraction of 33-mer peptide remained intact. Gliadin peptides derived from gastrointestinal digestion, especially the 33-mer, can potentially be used by commensal microbiota from both CD-positive and CD-negative individuals, and differences in bacterial hydrolysis can modify its immunogenic capacity.

Towards conducting inks: Polypyrrole–silver colloids

International Nuclear Information System (INIS)

Omastová, Mária; Bober, Patrycja; Morávková, Zuzana; Peřinka, Nikola; Kaplanová, Marie; Syrový, Tomáš; Hromádková, Jiřina; Trchová, Miroslava; Stejskal, Jaroslav

2014-01-01

Graphical abstract: - Highlights: • Composite colloidal particles combining conducting polymer and metal have been prepared. • Conducting colloids are suitable for printing applications. • Polypyrrole/silver colloids are prepared in a single reaction step. • The conductivity control is discussed and still needs improvement. - Abstract: The oxidation of pyrrole with silver nitrate in the presence of suitable water-soluble polymers yields composite polypyrrole–silver colloids. The polypyrrole–silver nanoparticles stabilized with poly(N-vinylpyrrolidone) have a typical size around 350 nm and polydispersity index 0.20, i.e. a moderate polydispersity in size. Similar results have been obtained with poly(vinyl alcohol) as stabilizer. The effect of stabilizer concentration on the particle size is marginal. In the present study, several types of stabilizers have been tested in addition to currently used poly(N-vinylpyrrolidone). Transmission electron microscopy and optical microscopy revealed the gemini morphology of polypyrrole and silver colloidal nanoparticles and confirmed their size and size-distribution determined by dynamic light scattering. The use of colloidal dispersions provides an efficient tool for the UV–vis and FT Raman spectroscopic characterization of polypyrrole, including the transition between polypyrrole salt and corresponding polypyrrole base. The dispersions were used for the preparation of coatings on polyethylene terephthalate foils, and the properties for polypyrrole–silver composites have been compared with those produced from polypyrrole colloids alone

The Gluten-Free Diet: Testing Alternative Cereals Tolerated by Celiac Patients

Directory of Open Access Journals (Sweden)

Carolina Sousa

2013-10-01

Full Text Available A strict gluten-free diet (GFD is the only currently available therapeutic treatment for patients with celiac disease, an autoimmune disorder of the small intestine associated with a permanent intolerance to gluten proteins. The complete elimination of gluten proteins contained in cereals from the diet is the key to celiac disease management. However, this generates numerous social and economic repercussions due to the ubiquity of gluten in foods. The research presented in this review focuses on the current status of alternative cereals and pseudocereals and their derivatives obtained by natural selection, breeding programs and transgenic or enzymatic technology, potential tolerated by celiac people. Finally, we describe several strategies for detoxification of dietary gluten. These included enzymatic cleavage of gliadin fragment by Prolyl endopeptidases (PEPs from different organisms, degradation of toxic peptides by germinating cereal enzymes and transamidation of cereal flours. This information can be used to search for and develop cereals with the baking and nutritional qualities of toxic cereals, but which do not exacerbate this condition.

Hemocompatibility of ultrafine systems on the basis of chitosan and its derivatives polymer-colloid complexes

Directory of Open Access Journals (Sweden)

M.V. Bazunova

2015-03-01

Full Text Available This article presents the results of the development process for the preparation of micro and nano-sized polymer-colloid com-plexes (РСС on the basis of water-soluble natural polymer chitosan (СTZ and the sodium salt of chitosan succinylamid (SСTZ with silver halide sols in aqueous media. Results of research of СTZ, sodium salt of SСTZ solutions and PСС of CTZ and SСTZ with colloidal parti-cles of silver iodide influence on structurally-functional properties of erythrocytes’ membranes on model of acidic hemolisis are presented in the article. Their influence on the nature of erythrocytes distribution by degree of their stability and on kinetic parameters (the beginning, intensity and completion of process of their destruction under the influence of the damaging agent (HCl is shown. The comparative analysis of results convinces that СTZ, SСTZ solutions and disperse systems on the basis of PСС of СTZ and SСTZ with colloidal particles of the silver iodide are capable of modulating variously matrix properties of erythrocytes of blood.

Prevalence of Self-Reported Gluten-Related Disorders and Adherence to a Gluten-Free Diet in Salvadoran Adult Population

Directory of Open Access Journals (Sweden)

Noé Ontiveros

2018-04-01

Full Text Available Gluten-related disorders are not considered of relevance at public health level in Central America. The prevalence of gluten-related disorders, and adherence to a gluten-free diet, remain unknown in the Central American region. We conducted a cross-sectional survey of the Central American population from San Salvador, El Salvador, to estimate the prevalence rates of self-reported gluten-related disorders and adherence to a gluten-free diet. 1326 individuals were surveyed. Self-reported prevalence rates were (95% Confidence Interval: gluten sensitivity 3.1% (2.3–4.2; physician-diagnosed celiac disease 0.15% (0.04–0.5; wheat allergy 0.75% (0.4–1.3; non-celiac gluten sensitivity 0.98% (0.5–1.6. The prevalence rate of adherence to a gluten-free diet was 7.0% (5.7–8.5. Seven self-reported physician diagnosed gluten-sensitive cases informed the co-existence of non-celiac gluten sensitivity with celiac disease and/or wheat allergy. Among the non-self-reported gluten sensitivity individuals following a gluten-free diet, 50% reported that they were seeing a health professional for gluten-free dietary advice. Gluten sensitivity is commonly reported in Salvadoran population, but some health professionals acknowledge the coexistence of wheat allergy, celiac disease, and non-celiac gluten sensitivity. Among studies at population level, the prevalence of adherence to a gluten-free diet in Salvadoran population is the highest reported until now. However, just a few of the gluten-free diet followers were doing it for health-related benefits; the others reported weight control and the perception that the diet is healthier as the main motivation for adopting such a diet.

Colloidal approach to dispersion and enhanced deaggregation of aqueous ferrite suspensions

Science.gov (United States)

Mandanas, Michael Patrick M.

The role of solution and surface chemistry on deaggregation of calcined ferrites during attrition (stirred-media) milling of aqueous suspensions were investigated. Suspensions of commercially calcined Fe2O 3 powder (d50 ˜ 5.0 mum) were milled at different solid loadings and suspension pH. The drift of suspension pH, from pH 2.5 to pH 7.0, during solid loading experiments accounted for the observed reagglomeration with milling time. The observed deaggregation rates during pH stat milling, in the acidic region, can be related to (i) elevated solubility and (ii) enhanced dispersion via surface charge. Proton adsorption density during pH stat milling at different pH values is also comparable to existing potentiometric titration plots and can be related to deaggregation rates. A passivation-dispersion approach for dispersing manganese zinc ferrite (MnxZn(1 - x)Fe2O4) powder is presented. Addition of oxalic acid can help control dissolution reactions from particle surfaces and is subsequently dispersed with polyethyleneimine (PEI). Fully dissociated oxalic acid (pK1 = 1.2, pK2 = 4.3) solutions reacted with MnxZn(1 - x)Fe 2O4 leads to the formation of a uniform negative charge on the particle surface, resulting from the sparingly soluble salt formed on the surface. The resulting rheological data for passivation/dispersion of relatively high solid MnxZn(1 - x)Fe2O 4 suspensions (˜80 w/o, (˜40 v/o)) demonstrate improved colloid stability with improved rheological properties. Using the passivation dispersion scheme developed, deaggregation of commercially calcined MnxZn(1 - x)Fe2O4 powders during attrition milling was investigated. Reagglomeration is apparent when using a typical treatment, 2 w/w of a sulfonated based naphthalene condensate, during deaggregation of the calcined MnxZn(1 - x)Fe 2O4. However, is not observed for select oxalate/PEI treatments. The determined ideal treatment is 2 w/w oxalate and 3 w/w PEI based on the particle size and rheological

Gluten contamination in gluten-free bakery products: a risk for coeliac disease patients.

Science.gov (United States)

Farage, Priscila; de Medeiros Nóbrega, Yanna Karla; Pratesi, Riccardo; Gandolfi, Lenora; Assunção, Pedro; Zandonadi, Renata Puppin

2017-02-01

The present study aimed to assess the safety of gluten-free bakery products for consumption by coeliac patients. Design/setting In the current exploratory cross-sectional quantitative study, a total of 130 samples were collected from twenty-five bakeries in Brasilia (Brazil). For the quantification of gluten, an ELISA was used. The threshold of 20 ppm gluten was considered as the safe upper limit for gluten-free food, as proposed in the Codex Alimentarius. The results revealed a total of 21·5 % of contamination among the bakery products sampled. Sixty-four per cent of the bakeries sold at least one contaminated product in our sample. These findings represent a risk for coeliac patients since the ingestion of gluten traces may be sufficient to adversely impact on their health.

Gluten - Not a Friendly Protein

OpenAIRE

E Tafreshi; A Jafarzade Noghani; B Khairkhah; M Yazdani; S Seddighi; S khayam

2014-01-01

Introduction: Gluten is a protein found in grains.  Research has shown that the gluten that is in grains of wheat, barley, rye, and oats (to a lesser degree) is toxic to many individuals.  While gluten is essential for the make-up of these 4 grains, our bodies do not need it. Is it healthful?  The protein in today’s wheat is poorly digested and can be harmful.  An estimated 95% of prepared foods on the grocery shelves contain the toxic forms of gluten.   Non-Celiac Gluten Sensitivit...

Wetting in a colloidal liquid-gas system

NARCIS (Netherlands)

Wijting, W.K.; Besseling, N.A.M.; Cohen Stuart, M.A.

2003-01-01

We present first observations of wetting phenomena in depletion interaction driven, phase separated colloidal dispersions (coated silica-cyclohexane-polydimethylsiloxane). The contact angle of the colloidal liquid-gas interface at a solid substrate (coated glass) was determined for a series of

Evolution of Gluten Content in Cereal-Based Gluten-Free Products: An Overview from 1998 to 2016

Directory of Open Access Journals (Sweden)

María Ángeles Bustamante

2017-01-01

Full Text Available The treatment of Celiac disease consists in a strict lifelong gluten-free (GF diet. As the ingestion of small amounts can have damaging complications, there has been an ongoing discussion regarding the safe threshold for dietary residual gluten. The aim was to analyze the evolution of gluten content in cereal-based GF foodstuffs (n = 3141 from 1998 to 2016 measured by the enzyme-linked immunosorbent assay (ELISA technique. Eight categories were defined: flours, breakfast cereals/bars, bakery, pasta, breads, dough, snacks, and yeasts, and these were divided into GF labeled-foods (GF-L or reportedly GF foodstuffs, but not certified (GF-NC. Gluten-detection was decreased over time in line with the evolving European regulations about food information and gluten content claims. This decline started sooner in GF-L products than in GF-NC. As a whole, gluten was detected in 371 samples, with breakfast cereals/bars being the most contaminated group. Snacks and yeasts changed from being high gluten-detected samples to being totally GF over the years. The downside is that, of contaminated samples, those in the low levels of gluten detection range have decreased while flour samples containing over 100 mg/kg gluten have risen in the 2013–2016 period. Obtained data confirm that GF cereal-based foods are becoming safer but gluten control must be maintained.

Removing celiac disease-related gluten proteins from bread wheat while retaining technological properties: a study with Chinese spring deletion lines

NARCIS (Netherlands)

van den Broeck, H.C.; van Herpen, T.W.J.M.; Schuit, C.; Salentijn, E.M.J.; Dekking, L.; Bosch, D.|info:eu-repo/dai/nl/073731374; Hamer, R.J.; Smulders, M.J.M.; Gilissen, L.J.W.J.; van der Meer, I.M.

2009-01-01

Background: Gluten proteins can induce celiac disease (CD) in genetically susceptible individuals. In CD patients gluten-derived peptides are presented to the immune system, which leads to a CD4+ T-cell mediated immune response and inflammation of the small intestine. However, not all gluten

Gluten-Free Labeling of Foods

Science.gov (United States)

... issued a final rule defining “gluten-free” for food labeling, which will help consumers, especially those living with ... free” label on foods. Food Facts: Gluten and Food Labeling: FDA’s Regulation of “Gluten-Free” Claims Blog: A ...

[Nutritional assessment of gluten-free diet. Is gluten-free diet deficient in some nutrient?].

Science.gov (United States)

Salazar Quero, J C; Espín Jaime, B; Rodríguez Martínez, A; Argüelles Martín, F; García Jiménez, R; Rubio Murillo, M; Pizarro Martín, A

2015-07-01

The gluten-free diet has traditionally been accepted as a healthy diet, but there are articles advocating that it may have some nutritional deficiencies. The current study assesses whether there was any change in the contributions of calories, essential elements, proportion of fatty acids, vitamins, minerals and fiber in children who were diagnosed with celiac diseases, comparing the diet with gluten prior one year after diagnosis with the diet without gluten to the year of diagnosis. The level of clinical or analytical impact that nutritional deficits could have was also assessed. A prospective,descriptive, observational study in which information was collected from a dietary survey, anthropometric and analytical data at pre-diagnosis of celiac disease and following a gluten diet and one year after celiac disease diagnosis, under gluten-free diet. A total of 37 patients meet the study criteria. A decrease in the intake of saturated fatty acids was found, with an increase of monounsaturated fatty acids and an increase in the intake of phosphorus in the diet without gluten. A deficient intake of vitamin D was found in both diets. Clinically, at year of gluten-free diet there was an improvement in weight and size. Analytically, there was an improvement in hemoglobin, ferritin, vitamin D, and parathyroid hormone in plasma. The gluten-free diet has minimal deficiencies, similar to those present in the diet with gluten, with an improvement in the lipid profile by increasing the proportion of monounsaturated fatty acids to the detriment of saturated fatty acids. Copyright © 2014 Asociación Española de Pediatría. Published by Elsevier España, S.L.U. All rights reserved.

Self-Reported Prevalence of Gluten-Related Disorders and Adherence to Gluten-Free Diet in Colombian Adult Population

Directory of Open Access Journals (Sweden)

Francisco Cabrera-Chávez

2016-01-01

Full Text Available Background. Celiac disease seems to be rare in Colombians, but there are currently no data about the prevalence rates of symptomatic adverse reactions to gluten or adherence to gluten-free diet (GFD in this population. Aim. to evaluate the self-reported prevalence rates of adverse reactions to gluten, adherence to GFD, and gluten-related disorders at population level in Colombia. Methods. A self-administered questionnaire-based cross-sectional study was conducted in a population from Northwest Colombia. Results. The estimated prevalence rates were (95% CI 7.9% (6.5–9.6 and 5.3% (4.1–6.7 for adverse and recurrent adverse reactions to wheat/gluten, respectively, adherence to GFD 5.9% (4.7–7.4, wheat allergy 0.74% (0.3–1.4, and nonceliac gluten sensitivity 4.5% (3.5–5.8. There were no self-reported cases of celiac disease. Prevalence of self-reported physician-diagnosis of gluten-related disorders was 0.41% (0.17–0.96. Most respondents reported adherence to GFD without a physician-diagnosis of gluten-related disorders (97.2%. The proportion of gluten avoiders was 17.2% (15.2–19.5. Most of them did not report recurrent adverse reactions to wheat/gluten (87.0%. Conclusions. Nonceliac gluten sensitivity is rarely formally diagnosed in Colombia, but this population has the highest prevalence rate of adherence to GFD reported to date. Consequently, most respondents were avoiding wheat- and/or gluten-based products for reasons other than health-related symptoms.

Stress modeling in colloidal dispersions undergoing non-viscometric flows

Science.gov (United States)

Dolata, Benjamin; Zia, Roseanna

2017-11-01

We present a theoretical study of the stress tensor for a colloidal dispersion undergoing non-viscometric flow. In such flows, the non-homogeneous suspension stress depends on not only the local average total stresslet-the sum of symmetric first moments of both the hydrodynamic traction and the interparticle force-but also on the average quadrupole, octupole, and higher-order moments. To compute the average moments, we formulate a six dimensional Smoluchowski equation governing the microstructural evolution of a suspension in an arbitrary fluid velocity field. Under the conditions of rheologically slow flow, where the Brownian relaxation of the particles is much faster than the spatiotemporal evolution of the flow, the Smoluchowski equation permits asymptotic solution, revealing a suspension stress that follows a second-order fluid constitutive model. We obtain a reciprocal theorem and utilize it to show that all constitutive parameters of the second-order fluid model may be obtained from two simpler linear-response problems: a suspension undergoing simple shear and a suspension undergoing isotropic expansion. The consequences of relaxing the assumption of rheologically slow flow, including the appearance of memory and microcontinuum behaviors, are discussed.

Differences in gluten metabolism among healthy volunteers, coeliac disease patients and first-degree relatives.

Science.gov (United States)

Caminero, Alberto; Nistal, Esther; Herrán, Alexandra R; Pérez-Andrés, Jénifer; Ferrero, Miguel A; Vaquero Ayala, Luis; Vivas, Santiago; Ruiz de Morales, José M G; Albillos, Silvia M; Casqueiro, Francisco Javier

2015-10-28

Coeliac disease (CD) is an immune-mediated enteropathy resulting from exposure to gluten in genetically predisposed individuals. Gluten proteins are partially digested by human proteases generating immunogenic peptides that cause inflammation in patients carrying HLA-DQ2 and DQ8 genes. Although intestinal dysbiosis has been associated with patients with CD, bacterial metabolism of gluten has not been studied in depth thus far. The aim of this study was to analyse the metabolic activity of intestinal bacteria associated with gluten intake in healthy individuals, CD patients and first-degree relatives of CD patients. Faecal samples belonging to twenty-two untreated CD patients, twenty treated CD patients, sixteen healthy volunteers on normal diet, eleven healthy volunteers on gluten-free diet (GFD), seventy-one relatives of CD patients on normal diet and sixty-nine relatives on GFD were tested for several proteolytic activities, cultivable bacteria involved in gluten metabolism, SCFA and the amount of gluten in faeces. We detected faecal peptidasic activity against the gluten-derived peptide 33-mer. CD patients showed differences in faecal glutenasic activity (FGA), faecal tryptic activity (FTA), SCFA and faecal gluten content with respect to healthy volunteers. Alterations in specific bacterial groups metabolising gluten such as Clostridium or Lactobacillus were reported in CD patients. Relatives showed similar parameters to CD patients (SCFA) and healthy volunteers (FTA and FGA). Our data support the fact that commensal microbial activity is an important factor in the metabolism of gluten proteins and that this activity is altered in CD patients.

Non-iridescent structural colors from uniform-sized SiO2 colloids

Science.gov (United States)

Topçu, Gökhan; Güner, Tuğrul; Demir, Mustafa M.

2018-05-01

Structural colors have recently attracted interest from diverse fields of research due to their ease of fabrication and eco-friendliness. These types of colors are, in principle, achieved by periodically arranged submicron-diameter colloidal particles. The interaction of light with a structure containing long-range ordered colloidal particles leads to coloration; this usually varies depending on the angle of observation (iridescence). However, the majority of the applications demand constant color that is independent of the viewing angle (non-iridescence). In this work, silica colloids were obtained using the Stöber method at different sizes from 150 to 300 nm in an alcoholic dispersion. The casting of the dispersion on a substrate leaves behind a photonic crystal showing a colorful iridescent film. However, centrifugation and redispersion of the SiO2 particles into fresh solvent may cause the formation of small, aggregated silica domains in the new dispersion. The casting of this dispersion allows for the development of photonic glass, presumably due to the accumulation of aggregates showing stable colloidal film independent of viewing angle. Moreover, depending on the size of the silica colloids, non-iridescent photonic glasses with various colors (violet, blue, green, and orange) are obtained.

Colloid Release from Soil Aggregates

DEFF Research Database (Denmark)

Vendelboe, Anders Lindblad; Møldrup, Per; Schjønning, Per

2012-01-01

The content of water-dispersible colloids (WDC) has a major impact on soil functions and structural stability. In addition, the presence of mobile colloids may increase the risk of colloid-facilitated transport of strongly sorbing environmental contaminants. The WDC content was measured in 39 soils......, using laser diffraction, by agitating the samples using a wet-dispersion unit. This approach eliminated the need for long sedimentation times required by the more classical end-over-end shaking approach and provided information about the time-dependent release of WDC. The total clay content of the soils...... ranged from 0.1 to 0.44 kg kg−1. The WDC content was measured on air-dry and moist 1- to 2-mm aggregates. The WDC content at a reference time was highly correlated to the total clay content (r > 0.91, P soils. Only for two sites was the WDC content correlated to the content of clay...

Gluten-related disorders: certainties, questions and doubts.

Science.gov (United States)

Valenti, Simona; Corica, Domenico; Ricciardi, Luisa; Romano, Claudio

2017-11-01

In the last decade, the ingestion of gluten, a heterogeneous complex of proteins present in wheat, rice, barley and probably in oats, has been associated with clinical disorders, such as celiac disease, wheat allergy and recently to non-celiac gluten sensitivity or wheat intolerance syndrome. Gluten-related disorders, which are becoming epidemiologically relevant with an estimated global prevalence of about 5%, require the exclusion of gluten from the diet. For the past 5 years, an important shift in the availability of gluten-free products, together with increased consumption in the general population, has been recorded and is estimated to be about 12-25%. Many people follow a self-prescribed gluten-free diet, despite the fact that the majority have not first been previously excluded, or confirmed, as having gluten disorders. They rely on claims that a gluten-free diet improves general health. In this review, we provide an overview of the clinical disorders related to gluten or wheat ingestion, pointing out the current certainties, open questions, possible answers and several doubts in the management of these conditions. KEY MESSAGE Incidence of gluten-related disorders is increased in the last decade and self-diagnosis is frequent with inappropriate starting of a gluten-free diet. Gluten and wheat are considered as the most important triggers to coeliac disease, wheat allergy and non-celiac gluten sensitivity. Pediatricians, allergologist and gastroenterologist are involved in the management of these conditions and appropriate diagnostic protocols are required.

Gluten-free diet - facts and myths.

OpenAIRE

Hejduk Bobková, Barbora

2017-01-01

The aim of this bachelor thesis was to gain a comprehensive view of the gluten-free diet and to confirm or refute the claim that the gluten-free diet became a fashion trend in nutrition. The theoretical part explains the relationship between gluten-free diet and diseases caused by intolerance of gluten. Greater attention is paid to the most serious of these, celiac disease, whose only treatment is gluten-free diet Research of commonly available sources for the general public has produced a li...

21 CFR 184.1322 - Wheat gluten.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Wheat gluten. 184.1322 Section 184.1322 Food and... Substances Affirmed as GRAS § 184.1322 Wheat gluten. (a) Wheat gluten (CAS Reg. No. 8002-80-0) is the principal protein component of wheat and consists mainly of gliadin and glutenin. Wheat gluten is obtained...

21 CFR 184.1321 - Corn gluten.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Corn gluten. 184.1321 Section 184.1321 Food and... Substances Affirmed as GRAS § 184.1321 Corn gluten. (a) Corn gluten (CAS Reg. No. 66071-96-3), also known as corn gluten meal, is the principal protein component of corn endosperm. It consists mainly of zein and...

Cell-compatible conducting polyaniline films prepared in colloidal dispersion mode.

Science.gov (United States)

Kašpárková, Věra; Humpolíček, Petr; Capáková, Zdenka; Bober, Patrycja; Stejskal, Jaroslav; Trchová, Miroslava; Rejmontová, Petra; Junkar, Ita; Lehocký, Marián; Mozetič, Miran

2017-09-01

Conducting polyaniline can be prepared and modified using several procedures, all of which can significantly influence its applicability in different fields of biomedicine or biotechnology. The modifications of surface properties are crucial with respect to the possible applications of this polymer in tissue engineering or as biosensors. Innovative technique for preparing polyaniline films via in-situ polymerization in colloidal dispersion mode using four stabilizers (poly-N-vinylpyrrolidone; sodium dodecylsulfate; Tween 20 and Pluronic F108) was developed. The surface energy, conductivity, spectroscopic features, and cell compatibility of thin polyaniline films were determined using contact-angle measurement, the van der Pauw method, Fourier-transform infrared spectroscopy, and assay conducted on mouse fibroblasts, respectively. The stabilizers significantly influenced not only the surface and electrical properties of the films but also their cell compatibility. Sodium dodecylsulfate seems preferentially to combine both the high conductivity and good cell compatibility. Moreover, the films with sodium dodecylsulfate were non-irritant for skin, which was confirmed by their in-vitro exposure to the 3D-reconstructed human tissue model. Copyright © 2017 Elsevier B.V. All rights reserved.

Interaction of water extractable pentosans with gluten protein : effect on dough properties and gluten quality

NARCIS (Netherlands)

Wang, M.; Hamer, R.J.; Vliet, van T.; Oudgenoeg, G.

2002-01-01

The effects of modified water extractable pentosans (WEP) on gluten yield, dough properties, gluten quality and composition were studied. The results show that WEP interfere with gluten formation in both a direct and an indirect way. WEP interfere indirectly by competing for water and thus changing

Preparation and dispersive properties of Ag colloid by electrical explosion of wire

International Nuclear Information System (INIS)

Yun, G.S.; Bac, L.H.; Kim, J.S.; Kwon, Y.S.; Choi, H.S.; Kim, J.C.

2011-01-01

Research highlights: → Wire diameter and synthetic temperature affect on properties of Ag colloid by EEW. → The lower temperature and smaller diameter make smaller size and narrower size distribution. → Ag colloid are more stable at lower synthetic temperature and smaller size. - Abstract: In this work, Ag colloid was prepared by electrical explosion of wire in deionized water with 0.2 mm and 0.3 mm wire diameter. The temperature of water used for medium of explosion process was change from 20 deg. C to 80 deg. C. Morphology and particle size of nanoparticles was observed by transmission electron microscope. The particle size and size distribution of nanoparticles was found to shift to a smaller size with a decrease of temperature and smaller wire diameter. Surface plasmon resonance of the silver colloids was studied by UV-vis spectroscopy. Stability of silver colloids was investigated by zeta-potential and Turbiscan techniques. The results indicated that temperature of medium during explosion affects much on the stability of Ag colloid. The silver colloidal stability prepared at lower temperature and smaller wire diameter was more stable.

Diagnosis of gluten related disorders: Celiac disease, wheat allergy and non-celiac gluten sensitivity.

Science.gov (United States)

Elli, Luca; Branchi, Federica; Tomba, Carolina; Villalta, Danilo; Norsa, Lorenzo; Ferretti, Francesca; Roncoroni, Leda; Bardella, Maria Teresa

2015-06-21

Cereal crops and cereal consumption have had a vital role in Mankind's history. In the recent years gluten ingestion has been linked with a range of clinical disorders. Gluten-related disorders have gradually emerged as an epidemiologically relevant phenomenon with an estimated global prevalence around 5%. Celiac disease, wheat allergy and non-celiac gluten sensitivity represent different gluten-related disorders. Similar clinical manifestations can be observed in these disorders, yet there are peculiar pathogenetic pathways involved in their development. Celiac disease and wheat allergy have been extensively studied, while non-celiac gluten sensitivity is a relatively novel clinical entity, believed to be closely related to other gastrointestinal functional syndromes. The diagnosis of celiac disease and wheat allergy is based on a combination of findings from the patient's clinical history and specific tests, including serology and duodenal biopsies in case of celiac disease, or laboratory and functional assays for wheat allergy. On the other hand, non-celiac gluten sensitivity is still mainly a diagnosis of exclusion, in the absence of clear-cut diagnostic criteria. A multimodal pragmatic approach combining findings from the clinical history, symptoms, serological and histological tests is required in order to reach an accurate diagnosis. A thorough knowledge of the differences and overlap in clinical presentation among gluten-related disorders, and between them and other gastrointestinal disorders, will help clinicians in the process of differential diagnosis.

Amphotericin B colloidal dispersion (Amphocil) vs fluconazole for the prevention of fungal infections in neutropenic patients : data of a prematurely stopped clinical trial

NARCIS (Netherlands)

Timmers, G J; Zweegman, S; Simoons-Smit, A M; van Loenen, A C; Touw, D; Huijgens, P C

We conducted an open label, randomised clinical trial to compare amphotericin B colloidal dispersion (ABCD, Amphocil) 2 mg/kg/day intravenously with fluconazole 200 mg/day orally, for the prevention of fungal disease in neutropenic patients with haematological malignancies. In the event of

Gluten characteristics imparting bread quality in wheats differing for high molecular weight glutenin subunits at Glu D1 locus.

Science.gov (United States)

Mohan, Devinder; Gupta, Raj Kumar

2015-07-01

High yielding genotypes differing for high molecular weight glutenin subunits at Glu D1 locus in national wheat programme of India were examined for bread loaf volume, gluten and protein contents, gluten strength, gluten index and protein-gluten ratio. Number of superior bread quality genotypes in four agro-climatically diverse zones of Indian plains was comparable in both categories of wheat i.e., 5 + 10 and 2 + 12. There wasn't any difference in average bread loaf volume and grain protein content either. 5 + 10 wheats showed better gluten strength and their gluten quality was also superior in the zones where protein content was high. 2 + 10 wheats exerted more gluten due to better protein-gluten ratio. Good bread making in 5 + 10 was derived by better gluten strength and also gluten quality in certain regions but bread quality in 2 + 12 wheats was channelized through higher gluten content as they were more efficient in extracting gluten from per unit protein. Difference in route to bread quality was apparent as gluten content and gluten strength were the key gluten attributes in 5 + 10 whereas protein content and gluten index were prominent in 2 + 12 types. Unlike 2 + 12, there was a ceiling in gluten harvest of 5 + 10 wheats as higher protein failed to deliver more gluten after some limit.

Liquid Crystal Phases of Colloidal Platelets and their Use as Nanocomposite Templates

NARCIS (Netherlands)

Mourad, M.C.D.|info:eu-repo/dai/nl/304837563

2009-01-01

This thesis explores the gelation and liquid crystal phase behavior of colloidal dispersions of platelike particles as well as the use of such dispersions for the generation of nanocomposites. We report on the sol-gel, sol-glass and liquid crystal phase transitions of positively charged colloidal

A non-human primate model for gluten sensitivity.

Directory of Open Access Journals (Sweden)

Michael T Bethune

2008-02-01

Full Text Available Gluten sensitivity is widespread among humans. For example, in celiac disease patients, an inflammatory response to dietary gluten leads to enteropathy, malabsorption, circulating antibodies against gluten and transglutaminase 2, and clinical symptoms such as diarrhea. There is a growing need in fundamental and translational research for animal models that exhibit aspects of human gluten sensitivity.Using ELISA-based antibody assays, we screened a population of captive rhesus macaques with chronic diarrhea of non-infectious origin to estimate the incidence of gluten sensitivity. A selected animal with elevated anti-gliadin antibodies and a matched control were extensively studied through alternating periods of gluten-free diet and gluten challenge. Blinded clinical and histological evaluations were conducted to seek evidence for gluten sensitivity.When fed with a gluten-containing diet, gluten-sensitive macaques showed signs and symptoms of celiac disease including chronic diarrhea, malabsorptive steatorrhea, intestinal lesions and anti-gliadin antibodies. A gluten-free diet reversed these clinical, histological and serological features, while reintroduction of dietary gluten caused rapid relapse.Gluten-sensitive rhesus macaques may be an attractive resource for investigating both the pathogenesis and the treatment of celiac disease.

Interaction of water unextractable solids with gluten protein: Effect on dough properties and gluten quality

NARCIS (Netherlands)

Wang, M.; Oudgenoeg, G.; Vliet, T. van; Hamer, R.J.

2003-01-01

In a previous study, we have shown that water unextractable solids (WUS) interfere with gluten formation and affect the quality of the resulting gluten. In this study we aim to explain how WUS can affect the process of gluten formation. To this end, WUS were modified with NaOH, xylanase, horseradish

Interaction of water unextractable solids with gluten protein: effect on dough properties and gluten quality

NARCIS (Netherlands)

Wang, M.; Oudgenoeg, G.; Vliet, van T.; Hamer, R.J.

2003-01-01

Abstract In a previous study, we have shown that water unextractable solids (WUS) interfere with gluten formation and affect the quality of the resulting gluten. In this study we aim to explain how WUS can affect the process of gluten formation. To this end, WUS were modified with NaOH, xylanase,

Translational Chemistry Meets Gluten-Related Disorders.

Science.gov (United States)

Lammers, Karen M; Herrera, Maria G; Dodero, Veronica I

2018-03-01

Gluten-related disorders are a complex group of diseases that involve the activation of the immune system triggered by the ingestion of gluten. Among these, celiac disease, with a prevalence of 1 %, is the most investigated, but recently, a new pathology, named nonceliac gluten sensitivity, was reported with a general prevalence of 7 %. Finally, there other less-prevalent gluten-related diseases such as wheat allergy, gluten ataxia, and dermatitis herpetiformis (with an overall prevalence of less than 0.1 %). As mentioned, the common molecular trigger is gluten, a complex mixture of storage proteins present in wheat, barley, and a variety of oats that are not fully degraded by humans. The most-studied protein related to disease is gliadin, present in wheat, which possesses in its sequence many pathological fragments. Despite a lot of effort to treat these disorders, the only effective method is a long-life gluten-free diet. This Review summarizes the actual knowledge of gluten-related disorders from a translational chemistry point of view. We discuss what is currently known from the literature about the interaction of gluten with the gut and the critical host responses it evokes and, finally, connect them to our current and novel molecular understanding of the supramolecular organization of gliadin and the 33-mer gliadin peptide fragment under physiological conditions.

Depletion and the dynamics in colloid-polymer mixtures

NARCIS (Netherlands)

Tuinier, R.; Fan, T.H.; Taniguchi, T.

2015-01-01

The status of work on the influence of nonadsorbing polymers on depletion dynamics in colloidal dispersions is reviewed. In the past focus has been paid to equilibrium properties of colloid-polymer mixtures. In practice the dynamical behaviour is equally important. Dynamic properties including

Distribution of gluten proteins in bread wheat (Triticum aestivum) grain.

Science.gov (United States)

Tosi, Paola; Gritsch, Cristina Sanchis; He, Jibin; Shewry, Peter R

2011-07-01

Gluten proteins are the major storage protein fraction in the mature wheat grain. They are restricted to the starchy endosperm, which forms white flour on milling, and interact during grain development to form large polymers which form a continuous proteinaceous network when flour is mixed with water to give dough. This network confers viscosity and elasticity to the dough, enabling the production of leavened products. The starchy endosperm is not a homogeneous tissue and quantitative and qualitative gradients exist for the major components: protein, starch and cell wall polysaccharides. Gradients in protein content and composition are the most evident and are of particular interest because of the major role played by the gluten proteins in determining grain processing quality. Protein gradients in the starchy endosperm were investigated using antibodies for specific gluten protein types for immunolocalization in developing grains and for western blot analysis of protein extracts from flour fractions obtained by sequential abrasion (pearling) to prepare tissue layers. Differential patterns of distribution were found for the high-molecular-weight subunits of glutenin (HMW-GS) and γ-gliadins when compared with the low-molecular-weight subunits of glutenin (LMW-GS), ω- and α-gliadins. The first two types of gluten protein are more abundant in the inner endosperm layers and the latter more abundant in the subaleurone. Immunolocalization also showed that segregation of gluten proteins occurs both between and within protein bodies during protein deposition and may still be retained in the mature grain. Quantitative and qualitative gradients in gluten protein composition are established during grain development. These gradients may be due to the origin of subaleurone cells, which unlike other starchy endosperm cells derive from the re-differentiation of aleurone cells, but could also result from the action of specific regulatory signals produced by the maternal tissue

Diagnosis of gluten related disorders: Celiac disease, wheat allergy and non-celiac gluten sensitivity

Science.gov (United States)

Elli, Luca; Branchi, Federica; Tomba, Carolina; Villalta, Danilo; Norsa, Lorenzo; Ferretti, Francesca; Roncoroni, Leda; Bardella, Maria Teresa

2015-01-01

Cereal crops and cereal consumption have had a vital role in Mankind’s history. In the recent years gluten ingestion has been linked with a range of clinical disorders. Gluten-related disorders have gradually emerged as an epidemiologically relevant phenomenon with an estimated global prevalence around 5%. Celiac disease, wheat allergy and non-celiac gluten sensitivity represent different gluten-related disorders. Similar clinical manifestations can be observed in these disorders, yet there are peculiar pathogenetic pathways involved in their development. Celiac disease and wheat allergy have been extensively studied, while non-celiac gluten sensitivity is a relatively novel clinical entity, believed to be closely related to other gastrointestinal functional syndromes. The diagnosis of celiac disease and wheat allergy is based on a combination of findings from the patient’s clinical history and specific tests, including serology and duodenal biopsies in case of celiac disease, or laboratory and functional assays for wheat allergy. On the other hand, non-celiac gluten sensitivity is still mainly a diagnosis of exclusion, in the absence of clear-cut diagnostic criteria. A multimodal pragmatic approach combining findings from the clinical history, symptoms, serological and histological tests is required in order to reach an accurate diagnosis. A thorough knowledge of the differences and overlap in clinical presentation among gluten-related disorders, and between them and other gastrointestinal disorders, will help clinicians in the process of differential diagnosis. PMID:26109797

Refractory iron-deficiency anemia and gluten intolerance: Response to gluten-free diet Anemia ferropénica refractaria e intolerancia al gluten: respuesta a la dieta sin gluten

Directory of Open Access Journals (Sweden)

Luis Rodrigo-Sáez

2011-07-01

Full Text Available Introduction: refractory iron-deficiency anemia has a multifactorial origin related to various gastrointestinal conditions, with celiac disease plus malabsorption and IBD together with isolated gluten intolerance being most common. Objectives: to determine the prevalence of serum, genetic, and histological markers for gluten intolerance, and to analyze the response to gluten withdrawal from the diet in these patients. Methods: a number of patients with refractory anemia were prospectively and consecutively enrolled. A protocol to measure serum (TGt-2, genetic (HLA-DQ2/DQ8, and histological markers for celiac disease was applied. All followed a gluten-free diet for a median 3.6 years. Sustained remission of anemia during follow-up was interpreted as positive response. Results: ninety-eight patients (84% females with a mean age of 54 years were studied. Anti-TGt2 antibodies were positive in 5% of cases. A total of 67 cases (68% were haplotype HLA-DQ2 or -DQ8 (+. We found villous atrophy (Marsh III in 13% of patients, and an inflammatory pattern (Marsh I or II in 13%. All remaining 72 patients (74% had no histological duodenal changes. Age, anemia duration, number of transfusions, number of parenteral iron doses, and time on a gluten-free diet were all compared according to the presence or absence of villous atrophy and HLA-DQ2/8 positivity, and no significant differences were found for any of the analyzed variables. Response was positive in 92% of subjects. Conclusions: celiac disease with villous atrophy is rarely a cause of refractory anemia. Gluten intolerance with no histological lesions is seen in almost 75% of patients, and therefore plays a relevant role in its development.Introducción: la anemia ferropénica refractaria presenta un origen multifactorial, relacionado con diversas enfermedades digestivas, siendo las más frecuentes la enfermedad celiaca con malabsorción y la EII junto con la intolerancia al gluten aislada. Objetivos

Self-Reported Prevalence of Symptomatic Adverse Reactions to Gluten and Adherence to Gluten-Free Diet in an Adult Mexican Population.

Science.gov (United States)

Ontiveros, Noe; López-Gallardo, Jesús A; Vergara-Jiménez, Marcela J; Cabrera-Chávez, Francisco

2015-07-21

The prevalence of symptomatic adverse reactions to gluten and adherence to gluten-free diet in Latin American countries is unknown. These measurements are strongly linked to gluten-related disorders. This work aimed to estimate the prevalence of adverse reactions to oral gluten and the adherence to gluten-free diet in the adult Mexican population. To reach this aim, a self-administered questionnaire was designed and tested for clarity/comprehension and reproducibility. Then, a self-administered questionnaire-based cross-sectional study was conducted in the Mexican population. The estimated prevalence rates were (95% CI): 11.9% (9.9-13.5) and 7.8 (6.4-9.4) for adverse and recurrent adverse reactions to gluten respectively; adherence to gluten-free diet 3.7% (2.7-4.8), wheat allergy 0.72% (0.38-1.37); celiac disease 0.08% (0.01-0.45), and NCGS 0.97% (0.55-1.68). Estimated pooled prevalence of self-reported physician-diagnosis of gluten-related disorders was 0.88% (0.49-1.5), and 93.3% respondents reported adherence to gluten-free diet without a physician-diagnosis of gluten-related disorders. Symptom comparisons between those who reported recurrent adverse reactions to gluten and other foods showed statistically significant differences for bloating, constipation, and tiredness (p Gluten-related disorders may be underdiagnosed in the Mexican population and most people adhering to a gluten-free diet are doing it without proper diagnostic work-up of these disorders, and probably without medical/dietician advice.

How gluten properties are affected by pentosans

NARCIS (Netherlands)

Wang, M.; Vliet, T. van; Hamer, R.J.

2004-01-01

During the wet separation of starch and gluten, both water extractable pentosans (WEP) and water unextractable solids (WUS) have a negative effect on gluten yield. Gluten properties are also affected: the gluten becomes less extensible. In comparison to the control, addition of WUS or WEP resulted

How gluten properties are effected by pentosans

NARCIS (Netherlands)

Wang, M.; Vliet, van T.; Hamer, R.J.

2004-01-01

During the wet separation of starch and gluten, both water extractable pentosans (WEP) and water unextractable solids (WUS) have a negative effect on gluten yield. Gluten properties are also affected: the gluten becomes less extensible. In comparison to the control, addition of WUS or WEP resulted

Wetting in a Colloidal Liquid-Gas System

Science.gov (United States)

Wijting, W. K.; Besseling, N. A.; Stuart, M. A.

2003-05-01

We present first observations of wetting phenomena in depletion interaction driven, phase separated colloidal dispersions (coated silica cyclohexane-polydimethylsiloxane). The contact angle of the colloidal liquid-gas interface at a solid substrate (coated glass) was determined for a series of compositions. Upon approach to the critical point, a transition occurs from partial to complete wetting.

Wetting in a colloidal liquid-gas system

OpenAIRE

Wijting, W.K.; Besseling, N.A.M.; Cohen Stuart, M.A.

2003-01-01

We present first observations of wetting phenomena in depletion interaction driven, phase separated colloidal dispersions (coated silica-cyclohexane-polydimethylsiloxane). The contact angle of the colloidal liquid-gas interface at a solid substrate (coated glass) was determined for a series of compositions. Upon approach to the critical point, a transition occurs from partial to complete wetting.

Self-Reported Prevalence of Symptomatic Adverse Reactions to Gluten and Adherence to Gluten-Free Diet in an Adult Mexican Population

Directory of Open Access Journals (Sweden)

Noe Ontiveros

2015-07-01

Full Text Available The prevalence of symptomatic adverse reactions to gluten and adherence to gluten-free diet in Latin American countries is unknown. These measurements are strongly linked to gluten-related disorders. This work aimed to estimate the prevalence of adverse reactions to oral gluten and the adherence to gluten-free diet in the adult Mexican population. To reach this aim, a self-administered questionnaire was designed and tested for clarity/comprehension and reproducibility. Then, a self-administered questionnaire-based cross-sectional study was conducted in the Mexican population. The estimated prevalence rates were (95% CI: 11.9% (9.9–13.5 and 7.8 (6.4–9.4 for adverse and recurrent adverse reactions to gluten respectively; adherence to gluten-free diet 3.7% (2.7–4.8, wheat allergy 0.72% (0.38–1.37; celiac disease 0.08% (0.01–0.45, and NCGS 0.97% (0.55–1.68. Estimated pooled prevalence of self-reported physician-diagnosis of gluten-related disorders was 0.88% (0.49–1.5, and 93.3% respondents reported adherence to gluten-free diet without a physician-diagnosis of gluten-related disorders. Symptom comparisons between those who reported recurrent adverse reactions to gluten and other foods showed statistically significant differences for bloating, constipation, and tiredness (p < 0.05. Gluten-related disorders may be underdiagnosed in the Mexican population and most people adhering to a gluten-free diet are doing it without proper diagnostic work-up of these disorders, and probably without medical/dietician advice.

Glass transition in soft-sphere dispersions

International Nuclear Information System (INIS)

RamIrez-Gonzalez, P E; Medina-Noyola, M

2009-01-01

The concept of dynamic equivalence among mono-disperse soft-sphere fluids is employed in the framework of the self-consistent generalized Langevin equation (SCGLE) theory of colloid dynamics to calculate the ideal glass transition phase diagram of model soft-sphere colloidal dispersions in the softness-concentration state space. The slow dynamics predicted by this theory near the glass transition is compared with available experimental data for the decay of the intermediate scattering function of colloidal dispersions of soft-microgel particles. Increasing deviations from this simple scheme occur for increasingly softer potentials, and this is studied here using the Rogers-Young static structure factor of the soft-sphere systems as the input of the SCGLE theory, without assuming a priori the validity of the equivalence principle above.

Holographic characterization of colloidal particles in turbid media

Science.gov (United States)

Cheong, Fook Chiong; Kasimbeg, Priya; Ruffner, David B.; Hlaing, Ei Hnin; Blusewicz, Jaroslaw M.; Philips, Laura A.; Grier, David G.

2017-10-01

Holographic particle characterization uses in-line holographic microscopy and the Lorenz-Mie theory of light scattering to measure the diameter and the refractive index of individual colloidal particles in their native dispersions. This wealth of information has proved invaluable in fields as diverse as soft-matter physics, biopharmaceuticals, wastewater management, and food science but so far has been available only for dispersions in transparent media. Here, we demonstrate that holographic characterization can yield precise and accurate results even when the particles of interest are dispersed in turbid media. By elucidating how multiple light scattering contributes to image formation in holographic microscopy, we establish the range conditions under which holographic characterization can reliably probe turbid samples. We validate the technique with measurements on model colloidal spheres dispersed in commercial nanoparticle slurries.

Celiac disease: understanding the gluten-free diet.

Science.gov (United States)

Bascuñán, Karla A; Vespa, María Catalina; Araya, Magdalena

2017-03-01

The only effective and safe treatment of celiac disease (CD) continues being strict exclusion of gluten for life, the so-called gluten-free diet (GFD). Although this treatment is highly successful, following strict GFD poses difficulties to patients in family, social and working contexts, deteriorating his/her quality of life. We aimed to review main characteristics of GFD with special emphasis on factors that may interfere with adherence to it. We conducted a search of various databases, such as PubMed, Google Scholar, Embase, and Scielo, with focus on key words such as "gluten-free diet", "celiac disease", "gluten" and "gluten-free diet adherence". Available literature has not reached definitive conclusions on the exact amount of gluten that is harmless to celiac patients, although international agreements establish cutoff points for gluten-free products and advise the use of clinical assessment to tailor the diet according to individual needs. Following GFD must include eliminating gluten as ingredient as well as hidden component and potential cross contamination in foods. There are numerous grains to substitute wheat but composition of most gluten-free products tends to include only a small number of them, especially rice. The diet must be not only free of gluten but also healthy to avoid nutrient, vitamins and minerals deficiencies or excess. Overweight/obesity frequency has increased among celiac patients so weight gain deserves attention during follow up. Nutritional education by a trained nutritionist is of great relevance to achieve long-term satisfactory health status and good compliance. A balanced GFD should be based on a combination of naturally gluten-free foods and certified processed gluten-free products. How to measure and improve adherence to GFD is still controversial and deserves further study.

Structure of magnetic particles studied by small angle neutron scattering. [Magnetic colloid particles in stable liquid dispersion

Energy Technology Data Exchange (ETDEWEB)

Cebula, D J; Charles, S W; Popplewell, J

1981-03-01

The purpose of this note is to show how the use of small angle neutron scattering (SANS) can provide fundamental information on the structure of magnetic colloid particles in stable liquid dispersion. A more detailed account elaborating the use of the technique to provide fundamental information on interactions will appear later. This contribution contains some principal results on particle structure. The technique of SANS provides a very sensitive means of measuring particle size by measuring the scattered neutron intensity, I(Q), as a function of scattered wave vector, Q.

Improved xenobiotic metabolism and reduced susceptibility to cancer in gluten-sensitive macaques upon introduction of a gluten-free diet.

Directory of Open Access Journals (Sweden)

Karol Sestak

2011-04-01

Full Text Available A non-human primate (NHP model of gluten sensitivity was employed to study the gene perturbations associated with dietary gluten changes in small intestinal tissues from gluten-sensitive rhesus macaques (Macaca mulatta.Stages of remission and relapse were accomplished in gluten-sensitive animals by administration of gluten-free (GFD and gluten-containing (GD diets, as described previously. Pin-head-sized biopsies, obtained non-invasively by pediatric endoscope from duodenum while on GFD or GD, were used for preparation of total RNA and gene profiling, using the commercial Rhesus Macaque Microarray (Agilent Technologies,targeting expression of over 20,000 genes.When compared with normal healthy control, gluten-sensitive macaques showed differential gene expressions induced by GD. While observed gene perturbations were classified into one of 12 overlapping categories--cancer, metabolism, digestive tract function, immune response, cell growth, signal transduction, autoimmunity, detoxification of xenobiotics, apoptosis, actin-collagen deposition, neuronal and unknown function--this study focused on cancer-related gene networks such as cytochrome P450 family (detoxification function and actin-collagen-matrix metalloproteinases (MMP genes.A loss of detoxification function paralleled with necessity to metabolize carcinogens was revealed in gluten-sensitive animals while on GD. An increase in cancer-promoting factors and a simultaneous decrease in cancer-preventing factors associated with altered expression of actin-collagen-MMP gene network were noted. In addition, gluten-sensitive macaques showed reduced number of differentially expressed genes including the cancer-associated ones upon withdrawal of dietary gluten. Taken together, these findings indicate potentially expanded utility of gluten-sensitive rhesus macaques in cancer research.

HLA-DQ-Gluten Tetramer Blood Test Accurately Identifies Patients With and Without Celiac Disease in Absence of Gluten Consumption.

Science.gov (United States)

Sarna, Vikas K; Lundin, Knut E A; Mørkrid, Lars; Qiao, Shuo-Wang; Sollid, Ludvig M; Christophersen, Asbjørn

2018-03-01

Celiac disease is characterized by HLA-DQ2/8-restricted responses of CD4+ T cells to cereal gluten proteins. A diagnosis of celiac disease based on serologic and histologic evidence requires patients to be on gluten-containing diets. The growing number of individuals adhering to a gluten-free diet (GFD) without exclusion of celiac disease complicates its detection. HLA-DQ-gluten tetramers can be used to detect gluten-specific T cells in blood of patients with celiac disease, even if they are on a GFD. We investigated whether an HLA-DQ-gluten tetramer-based assay accurately identifies patients with celiac disease. We produced HLA-DQ-gluten tetramers and added them to peripheral blood mononuclear cells isolated from 143 HLA-DQ2.5 + subjects (62 subjects with celiac disease on a GFD, 19 subjects without celiac disease on a GFD [due to self-reported gluten sensitivity], 10 subjects with celiac disease on a gluten-containing diet, and 52 presumed healthy individuals [controls]). T cells that bound HLA-DQ-gluten tetramers were quantified by flow cytometry. Laboratory tests and flow cytometry gating analyses were performed by researchers blinded to sample type, except for samples from subjects with celiac disease on a gluten-containing diet. Test precision analyses were performed using samples from 10 subjects. For the HLA-DQ-gluten tetramer-based assay, we combined flow-cytometry variables in a multiple regression model that identified individuals with celiac disease on a GFD with an area under the receiver operating characteristic curve value of 0.96 (95% confidence interval [CI] 0.89-1.00) vs subjects without celiac disease on a GFD. The assay detected individuals with celiac disease on a gluten-containing diet vs controls with an area under the receiver operating characteristic curve value of 0.95 (95% CI 0.90-1.00). Optimized cutoff values identified subjects with celiac disease on a GFD with 97% sensitivity (95% CI 0.92-1.00) and 95% specificity (95% CI 0

Biodegradability of wheat gluten based bioplastics.

Science.gov (United States)

Domenek, Sandra; Feuilloley, Pierre; Gratraud, Jean; Morel, Marie-Hélène; Guilbert, Stéphane

2004-01-01

A large variety of wheat gluten based bioplastics, which were plasticized with glycerol, were subjected to biodegradation. The materials covered the total range available for the biochemical control parameter Fi, which expresses the percentage of aggregated proteins. This quantity can be related to the density of covalent crosslinks in the wheat gluten network, which are induced by technological treatments. The biodegradability tests were performed in liquid medium (modified Sturm test) and in farmland soil. All gluten materials were fully degraded after 36 days in aerobic fermentation and within 50 days in farmland soil. No significant differences were observed between the samples. The mineralization half-life time of 3.8 days in the modified Sturm test situated gluten materials among fast degrading polymers. The tests of microbial inhibition experiments revealed no toxic effects of the modified gluten or of its metabolites. Thus, the protein bulk of wheat gluten materials is non-toxic and fully biodegradable, whatever the technological process applied.

Wetting behavior in colloid-polymer mixtures at different substrates

NARCIS (Netherlands)

Wijting, W.K.; Besseling, N.A.M.; Cohen Stuart, M.A.

2003-01-01

We present experimental observations on wetting phenomena in depletion interaction driven, phase separated colloidal dispersions. The contact angle of the colloidal liquid-gas interface at a solid substrate was determined for a series of compositions. Upon approach to the critical point, a

Quality of shear fractionated wheat gluten – comparison to commercial vital wheat gluten

NARCIS (Netherlands)

Zalm, van der E.E.J.; Goot, van der A.J.; Boom, R.M.

2011-01-01

The functional properties of gluten obtained with a shear-induced separation process, recently proposed by Peighambardoust et al. (2008), are compared with a commercially available vital wheat gluten. Two tests were performed. First, a relatively strong wheat flour, Soissons, was enriched with

Colloidal stabilization of cerium-gadolinium oxide (CGO) suspensions via rheology

DEFF Research Database (Denmark)

Marani, Debora; Sudireddy, Bhaskar Reddy; Bentzen, Janet Jonna

2015-01-01

colloidally stable state. The method was applied to explore the ability of four commercial dispersants (acidic affine, neutral, basic affine, and polyvinylpyrrolidone (PVP)) to disperse cerium-gadolinium oxide (CGO) in ethanol. Only the acidic affine and the PVP dispersants were found to efficiently disperse...

Celiac Disease and Nonceliac Gluten Sensitivity: A Review.

Science.gov (United States)

Leonard, Maureen M; Sapone, Anna; Catassi, Carlo; Fasano, Alessio

2017-08-15

The prevalence of gluten-related disorders is rising, and increasing numbers of individuals are empirically trying a gluten-free diet for a variety of signs and symptoms. This review aims to present current evidence regarding screening, diagnosis, and treatment for celiac disease and nonceliac gluten sensitivity. Celiac disease is a gluten-induced immune-mediated enteropathy characterized by a specific genetic genotype (HLA-DQ2 and HLA-DQ8 genes) and autoantibodies (antitissue transglutaminase and antiendomysial). Although the inflammatory process specifically targets the intestinal mucosa, patients may present with gastrointestinal signs or symptoms, extraintestinal signs or symptoms, or both, suggesting that celiac disease is a systemic disease. Nonceliac gluten sensitivity is diagnosed in individuals who do not have celiac disease or wheat allergy but who have intestinal symptoms, extraintestinal symptoms, or both, related to ingestion of gluten-containing grains, with symptomatic improvement on their withdrawal. The clinical variability and the lack of validated biomarkers for nonceliac gluten sensitivity make establishing the prevalence, reaching a diagnosis, and further study of this condition difficult. Nevertheless, it is possible to differentiate specific gluten-related disorders from other conditions, based on currently available investigations and algorithms. Clinicians cannot distinguish between celiac disease and nonceliac gluten sensitivity by symptoms, as they are similar in both. Therefore, screening for celiac disease must occur before a gluten-free diet is implemented, since once a patient initiates a gluten-free diet, testing for celiac disease is no longer accurate. Celiac disease and nonceliac gluten sensitivity are common. Although both conditions are treated with a gluten-free diet, distinguishing between celiac disease and nonceliac gluten sensitivity is important for long-term therapy. Patients with celiac disease should be followed up

Stabilized super-thermite colloids: A new generation of advanced highly energetic materials

Science.gov (United States)

Elbasuney, Sherif; Gaber Zaky, M.; Radwan, Mostafa; Mostafa, Sherif F.

2017-10-01

One of the great impetus of nanotechnology on energetic materials is the achievement of nanothermites (metal-oxide/metal) which are characterized by massive heat output. Yet, full exploitation of super-thermites in highly energetic systems has not been achieved. This manuscript reports on the sustainable fabrication of colloidal Fe2O3 and CuO nanoparticles for thermite applications. TEM micrographs demonstrated mono-dispersed Fe2O3 and CuO with an average particle size of 3 and 15 nm respectively. XRD diffractograms demonstrated highly crystalline materials. SEM micrographs demonstrated a great tendency of the developed oxides to aggregate over drying process. The effective integration and dispersion of mono-dispersed colloidal thermite particles into energetic systems are vital for enhanced performance. Aluminum is of interest as highly energetic metal fuel. In this paper, synthesized Fe2O3 and CuO nanoparticles were re-dispersed in isopropyl alcohol (IPA) with aluminum nanoparticles using ultrasonic prope homogenizer. The colloidal thermite peraticles can be intgegrated into highly energetic system for subsequent nanocomposite development. Thanks to stabilization of colloidal CuO nanoparticles in IPA which could offer intimate mixing between oxidizer and metal fuel. The stabilization mechanism of CuO in IPA was correlated to steric stabilization with solvent molecules. This approach eliminated nanoparticle drying and the re-dispersion of dry aggregates into energetic materials. This manuscript shaded the light on the real development of colloidal thermite mixtures and their integration into highly energetic systems.

Improved Xenobiotic Metabolism and Reduced Susceptibility to Cancer in Gluten-Sensitive Macaques upon Introduction of a Gluten-Free Diet

Science.gov (United States)

Sestak, Karol; Conroy, Lauren; Aye, Pyone P.; Mehra, Smriti; Doxiadis, Gaby G.; Kaushal, Deepak

2011-01-01

Background A non-human primate (NHP) model of gluten sensitivity was employed to study the gene perturbations associated with dietary gluten changes in small intestinal tissues from gluten-sensitive rhesus macaques (Macaca mulatta). Methodology Stages of remission and relapse were accomplished in gluten-sensitive animals by administration of gluten-free (GFD) and gluten-containing (GD) diets, as described previously. Pin-head-sized biopsies, obtained non-invasively by pediatric endoscope from duodenum while on GFD or GD, were used for preparation of total RNA and gene profiling, using the commercial Rhesus Macaque Microarray (Agilent Technologies),targeting expression of over 20,000 genes. Principal Findings When compared with normal healthy control, gluten-sensitive macaques showed differential gene expressions induced by GD. While observed gene perturbations were classified into one of 12 overlapping categories - cancer, metabolism, digestive tract function, immune response, cell growth, signal transduction, autoimmunity, detoxification of xenobiotics, apoptosis, actin-collagen deposition, neuronal and unknown function - this study focused on cancer-related gene networks such as cytochrome P450 family (detoxification function) and actin-collagen-matrix metalloproteinases (MMP) genes. Conclusions/Significance A loss of detoxification function paralleled with necessity to metabolize carcinogens was revealed in gluten-sensitive animals while on GD. An increase in cancer-promoting factors and a simultaneous decrease in cancer-preventing factors associated with altered expression of actin-collagen-MMP gene network were noted. In addition, gluten-sensitive macaques showed reduced number of differentially expressed genes including the cancer-associated ones upon withdrawal of dietary gluten. Taken together, these findings indicate potentially expanded utility of gluten-sensitive rhesus macaques in cancer research. PMID:21533263

Measurements of dispersion forces between colloidal latex particles with the atomic force microscope and comparison with Lifshitz theory

Energy Technology Data Exchange (ETDEWEB)

Elzbieciak-Wodka, Magdalena; Ruiz-Cabello, F. Javier Montes; Trefalt, Gregor; Maroni, Plinio; Borkovec, Michal, E-mail: michal.borkovec@unige.ch [Department of Inorganic and Analytical Chemistry, University of Geneva, Sciences II, 30, Quai Ernest-Ansermet, 1205 Geneva (Switzerland); Popescu, Mihail N. [Ian Wark Research Institute, University of South Australia, Mawson Lakes, SA 5095 (Australia)

2014-03-14

Interaction forces between carboxylate colloidal latex particles of about 2 μm in diameter immersed in aqueous solutions of monovalent salts were measured with the colloidal probe technique, which is based on the atomic force microscope. We have systematically varied the ionic strength, the type of salt, and also the surface charge densities of the particles through changes in the solution pH. Based on these measurements, we have accurately measured the dispersion forces acting between the particles and estimated the apparent Hamaker constant to be (2.0 ± 0.5) × 10{sup −21} J at a separation distance of about 10 nm. This value is basically independent of the salt concentration and the type of salt. Good agreement with Lifshitz theory is found when roughness effects are taken into account. The combination of retardation and roughness effects reduces the value of the apparent Hamaker constant and its ionic strength dependence with respect to the case of ideally smooth surfaces.

Stabilization of silica nanoparticles dispersions by surface modification with silicon derivative of thiacalix[4]arene

Energy Technology Data Exchange (ETDEWEB)

Gorbachuk, Vladimir V.; Ziatdinova, Ramilia V. [Kazan Federal University, A.M. Butlerov’ Chemical Institute (Russian Federation); Evtugyn, Vladimir G. [Kazan Federal University, Interdisciplinary Centre for Analytical Microscopy (Russian Federation); Stoikov, Ivan I., E-mail: ivan.stoikov@mail.ru [Kazan Federal University, A.M. Butlerov’ Chemical Institute (Russian Federation)

2015-03-15

For the first time, silica nanopowder functionalized with thiacalixarene derivatives was synthesized by ultrasonication of nanoparticles (diameter 23.7 ± 2.4 nm) with organosilicon derivative of thiacalixarene in glacial acetic acid. The protocol resulted in the formation of colloidal solution of low-disperse (polydispersity index of 0.11) submicron-sized (diameter 192.5 nm) clusters of nanoparticles according to the dynamic light scattering data. As defined by scanning electron microscopy (SEM), mean diameter of thiacalixarene-functionalized nanoparticles is equal to 25.5 ± 2.5 nm and the shape is close to spherical. SEM images confirm low aggregation of thiacalixarene-modified nanoparticle compared to initial silica nanopowder (mean diameter of aggregates 330 and 429 nm, correspondingly). According to the thermogravimetry/differential scanning calorimetry and elemental analysis of the nanoparticles obtained, 5 % of the powder mass was related to thiacalixarene units. The effect of thiacalixarene functionalization of silica nanoparticles on linear polydimethylsiloxane (PDMS)—silica dispersions was modeled to achieve high resistance toward liquid media required for similar sol–gel prepared PDMS-based materials applied for solid-phase microextraction. In such a manner, the influence of thiacalixarene-modified nanofiller on thermal stability and resistance against polar organic solvents was estimated. Similarity of decomposition temperature of both thiacalixarene-functionalized nanoparticles and non-functionalized silica nanoparticles was found. Swelling/solubility behavior observed was related to partial dissolution of PDMS/silica (10 % mixture) in alcohols. Thiacalixarene-functionalized silica particles exerted significantly higher resistance of PDMS/silica composites toward alcohol solvents.

Stabilization of silica nanoparticles dispersions by surface modification with silicon derivative of thiacalix[4]arene

International Nuclear Information System (INIS)

Gorbachuk, Vladimir V.; Ziatdinova, Ramilia V.; Evtugyn, Vladimir G.; Stoikov, Ivan I.

2015-01-01

For the first time, silica nanopowder functionalized with thiacalixarene derivatives was synthesized by ultrasonication of nanoparticles (diameter 23.7 ± 2.4 nm) with organosilicon derivative of thiacalixarene in glacial acetic acid. The protocol resulted in the formation of colloidal solution of low-disperse (polydispersity index of 0.11) submicron-sized (diameter 192.5 nm) clusters of nanoparticles according to the dynamic light scattering data. As defined by scanning electron microscopy (SEM), mean diameter of thiacalixarene-functionalized nanoparticles is equal to 25.5 ± 2.5 nm and the shape is close to spherical. SEM images confirm low aggregation of thiacalixarene-modified nanoparticle compared to initial silica nanopowder (mean diameter of aggregates 330 and 429 nm, correspondingly). According to the thermogravimetry/differential scanning calorimetry and elemental analysis of the nanoparticles obtained, 5 % of the powder mass was related to thiacalixarene units. The effect of thiacalixarene functionalization of silica nanoparticles on linear polydimethylsiloxane (PDMS)—silica dispersions was modeled to achieve high resistance toward liquid media required for similar sol–gel prepared PDMS-based materials applied for solid-phase microextraction. In such a manner, the influence of thiacalixarene-modified nanofiller on thermal stability and resistance against polar organic solvents was estimated. Similarity of decomposition temperature of both thiacalixarene-functionalized nanoparticles and non-functionalized silica nanoparticles was found. Swelling/solubility behavior observed was related to partial dissolution of PDMS/silica (10 % mixture) in alcohols. Thiacalixarene-functionalized silica particles exerted significantly higher resistance of PDMS/silica composites toward alcohol solvents

Hydrothermal synthesis of highly water-dispersible anatase nanocrystals from transparent aqueous sols of titanate colloids

International Nuclear Information System (INIS)

Ban, Takayuki; Tanaka, Yusuke; Ohya, Yutaka

2011-01-01

Transparent colloidal aqueous solutions of anatase nanocrystals were hydrothermally synthesized from aqueous transparent sols with tetramethylammonium titanate colloids, the surfaces of which were modified with citric acid, by structural conversion of the titanate to anatase. This modification hindered coalescence of the titanate colloids during the hydrothermal synthesis. Although the amount of citric acid adsorbed on the colloids was reduced during hydrothermal treatment, a small amount of citric acid was adsorbed on the resulting anatase nanocrystals. Moreover, the use of the titanate colloids as a precursor was compared with the use of a citrato Ti complex, tetramethylammonium citratotitanate. The hydrothermal treatment of the transparent aqueous solutions of the Ti complex yielded opaque solutions with large anatase colloids, suggesting that the titanate colloids were useful for preparing transparent anatase colloidal solutions. Because the shape and size of resulting colloids may be dependent on the size and shape of starting colloids, the use of titanate colloids as a precursor may make it easy to control size and shape of anatase colloids.

Celiac disease treatment: gluten-free diet and beyond.

Science.gov (United States)

Mäki, Markku

2014-07-01

The basis for celiac disease (CD) treatment is a strict lifelong gluten-free diet. On the diet, the small intestinal mucosal injury heals and gluten-induced symptoms and signs disappear. The mucosal healing is a prerequisite for sustaining health and is also obtained with a diet containing oats and trace amounts of gluten, industrially purified wheat starch-based gluten-free products. The small intestinal mucosa does not heal in noncompliant people, nor when a patient is inadvertently ingesting gluten. Development of adjunctive or alternative therapies is on its way. There are several novel treatment pipelines within academy and industry. Examples are the ideas of using glutenases as a drug to degrade the ingested gluten, polymers to bind and sequester the gluten to the feces, and also vaccine development for an immunotherapy to induce tolerance towards gluten. Clinical drug trials are to be foreseen in CD, soon also in children.

Targeted liquid chromatography tandem mass spectrometry to quantitate wheat gluten using well-defined reference proteins

Science.gov (United States)

Schalk, Kathrin; Koehler, Peter

2018-01-01

Celiac disease (CD) is an inflammatory disorder of the upper small intestine caused by the ingestion of storage proteins (prolamins and glutelins) from wheat, barley, rye, and, in rare cases, oats. CD patients need to follow a gluten-free diet by consuming gluten-free products with gluten contents of less than 20 mg/kg. Currently, the recommended method for the quantitative determination of gluten is an enzyme-linked immunosorbent assay (ELISA) based on the R5 monoclonal antibody. Because the R5 ELISA mostly detects the prolamin fraction of gluten, a new independent method is required to detect prolamins as well as glutelins. This paper presents the development of a method to quantitate 16 wheat marker peptides derived from all wheat gluten protein types by liquid chromatography tandem mass spectrometry (LC-MS/MS) in the multiple reaction monitoring mode. The quantitation of each marker peptide in the chymotryptic digest of a defined amount of the respective reference wheat protein type resulted in peptide-specific yields. This enabled the conversion of peptide into protein type concentrations. Gluten contents were expressed as sum of all determined protein type concentrations. This new method was applied to quantitate gluten in wheat starches and compared to R5 ELISA and gel-permeation high-performance liquid chromatography with fluorescence detection (GP-HPLC-FLD), which resulted in a strong correlation between LC-MS/MS and the other two methods. PMID:29425234

Targeted liquid chromatography tandem mass spectrometry to quantitate wheat gluten using well-defined reference proteins.

Directory of Open Access Journals (Sweden)

Kathrin Schalk

Full Text Available Celiac disease (CD is an inflammatory disorder of the upper small intestine caused by the ingestion of storage proteins (prolamins and glutelins from wheat, barley, rye, and, in rare cases, oats. CD patients need to follow a gluten-free diet by consuming gluten-free products with gluten contents of less than 20 mg/kg. Currently, the recommended method for the quantitative determination of gluten is an enzyme-linked immunosorbent assay (ELISA based on the R5 monoclonal antibody. Because the R5 ELISA mostly detects the prolamin fraction of gluten, a new independent method is required to detect prolamins as well as glutelins. This paper presents the development of a method to quantitate 16 wheat marker peptides derived from all wheat gluten protein types by liquid chromatography tandem mass spectrometry (LC-MS/MS in the multiple reaction monitoring mode. The quantitation of each marker peptide in the chymotryptic digest of a defined amount of the respective reference wheat protein type resulted in peptide-specific yields. This enabled the conversion of peptide into protein type concentrations. Gluten contents were expressed as sum of all determined protein type concentrations. This new method was applied to quantitate gluten in wheat starches and compared to R5 ELISA and gel-permeation high-performance liquid chromatography with fluorescence detection (GP-HPLC-FLD, which resulted in a strong correlation between LC-MS/MS and the other two methods.

Molekylaere mekanismer bag den immunologiske reaktion mod gluten hos patienter med cøliaki

DEFF Research Database (Denmark)

Nielsen, Christian; Husby, Steffen; Lillevang, Søren T

2003-01-01

Coeliac disease is a complex inflammatory disorder of the small intestine, induced by dietary gluten in genetically susceptible individuals. Recently, the nature of gluten-derived peptides recognized by gut-derived T cells from patients has been elucidated. It has further been established...... that the binding of such peptides to HLA-DQ2 and DQ8 molecules is enhanced following the modification of the peptides by the ubiquitous enzyme tissue transglutaminase. This knowledge has allowed the establishment of a molecular basis for the well-known association between coeliac disease and the expression...... of these HLA-molecules. This article summarizes the latest progress in coeliac disease molecular biology....

Particle morphology as a control of permeation in polymer films obtained from MMA/nBA colloidal dispersions.

Science.gov (United States)

Lestage, David J; Urban, Marek W

2004-07-20

The combination of precision-controlled weight loss measurements and spectroscopic surface FT-IR analysis allowed us to identify unique behaviors of poly(methyl methacrylate) (p-MMA). When MMA and n-butyl acrylate (nBA) are polymerized into p-MMA and p-nBA homopolymer blends, MMA/nBA random copolymers, and p-MMA/p-nBA core-shell morphologies, a controlled mobility and stratification of low molecular weight components occurs in films formed from coalesced colloidal dispersions. Due to different affinities toward water, p-MMA and p-nBA are capable of releasing water at different rates, depending upon particle morphological features of initial dispersions. As coalescence progresses, water molecules are released from the high free volume p-nBA particles, whereas p-MMA retains water molecules for the longest time due to its hydrophilic nature. As a result, water losses at extended coalescence times are relatively small for p-MMA. MMA/nBA copolymer and p-MMA/p-nBA blends follow the same trends, although the magnitudes of changes are not as pronounced. The p-MMA/p-nBA core-shell behavior resembles that of p-nBA homopolymer, which is attributed to significantly lower content of the p-MMA component in particles. Annealing of coalesced colloidal films at elevated temperatures causes migration of SDOSS to the F-A interface, but for films containing primarily p-nBA, reverse diffusion back into the bulk is observed. These studies illustrate that the combination of different particle morphologies and temperatures leads to controllable permeation processes through polymeric films. Copyright 2004 American Chemical Society

Using LC-MS to examine the fermented food products vinegar and soy sauce for the presence of gluten.

Science.gov (United States)

Li, Haili; Byrne, Keren; Galiamov, Renata; Mendoza-Porras, Omar; Bose, Utpal; Howitt, Crispin A; Colgrave, Michelle L

2018-07-15

A strict, lifelong gluten-free (GF) diet is currently the only treatment for coeliac disease (CD). Vinegar and soy sauce are fermented condiments that often include wheat and/or barley. During fermentation cereal proteins are partially degraded by enzymes to yield peptide fragments and amino acids. Whether these fermented products contain intact or degraded gluten proteins and if they are safe for people with CD remains in question. LC-MS offers the benefit of being able to detect hydrolysed gluten that might be present in commercial vinegar and soy sauce products. LC-MS revealed the presence of gluten in malt vinegar, wherein the identified peptides derived from B-, D- and γ-hordein from barley, as well as γ-gliadin, and HMW- and LMW-glutenins from wheat that are known to contain immunopathogenic epitopes. No gluten was detected in the soy sauces examined despite wheat being a labelled ingredient indicating extensive hydrolysis of gluten during soy sauce production. Copyright © 2018 Elsevier Ltd. All rights reserved.

Colloid transport in saturated porous media: Elimination of attachment efficiency in a new colloid transport model

Science.gov (United States)

Landkamer, Lee L.; Harvey, Ronald W.; Scheibe, Timothy D.; Ryan, Joseph N.

2013-01-01

A colloid transport model is introduced that is conceptually simple yet captures the essential features of colloid transport and retention in saturated porous media when colloid retention is dominated by the secondary minimum because an electrostatic barrier inhibits substantial deposition in the primary minimum. This model is based on conventional colloid filtration theory (CFT) but eliminates the empirical concept of attachment efficiency. The colloid deposition rate is computed directly from CFT by assuming all predicted interceptions of colloids by collectors result in at least temporary deposition in the secondary minimum. Also, a new paradigm for colloid re-entrainment based on colloid population heterogeneity is introduced. To accomplish this, the initial colloid population is divided into two fractions. One fraction, by virtue of physiochemical characteristics (e.g., size and charge), will always be re-entrained after capture in a secondary minimum. The remaining fraction of colloids, again as a result of physiochemical characteristics, will be retained “irreversibly” when captured by a secondary minimum. Assuming the dispersion coefficient can be estimated from tracer behavior, this model has only two fitting parameters: (1) the fraction of the initial colloid population that will be retained “irreversibly” upon interception by a secondary minimum, and (2) the rate at which reversibly retained colloids leave the secondary minimum. These two parameters were correlated to the depth of the Derjaguin-Landau-Verwey-Overbeek (DLVO) secondary energy minimum and pore-water velocity, two physical forces that influence colloid transport. Given this correlation, the model serves as a heuristic tool for exploring the influence of physical parameters such as surface potential and fluid velocity on colloid transport.

USE OF WOOD DERIVATIVES AS DOPING / DISPERSING AGENTS IN THE PREPARATION OF POLYPYRROLE AQUEOUS DISPERSIONS

Directory of Open Access Journals (Sweden)

Claudia Sasso

2008-11-01

Full Text Available Polystyrene sulfonic acid (PSS, lignosulfonic acid (LS sodium salts, and carboxymethylcellulose (CMC were used as doping/dispersing agents in the chemical polymerization of polypyrrole (Ppy. Conductivity measure-ments performed on dry Ppy pellets showed a sharp increase in conductivity when adding the anionic polymers to the polymerization liquor. For a polyanion/pyrrole weight ratio ranging between 0.1 and 0.6, the highest conductivity was given by PpyCMC (82 S/m and PpyPSS (80 S/m, followed by PpyLS (6 S/m. On the other hand, for a polyanion/pyrrole ratio higher than 0.6, the conductivity of PpyPSS systems sharply decreased, and for polyanion/pyrrole ratios higher than 1, the highest conductivity was given by PpyCMC (~10 S/m, followed by PpyLS (~7 S/m and PpyPSS (~5 S/m. Zeta-potential measurements showed that the surface charge of Ppy was strongly affected by the polyanion type and amount. Cationic Ppy particles were obtained in the presence of the two polymers bearing strongly acidic moieties (PSS and LS. Anionic PpyPSS colloids were obtained at the highest PSS/Py ratio, after the degradation of the conducting properties. When using a weakly acidic dopant (CMC, PpyCMC colloids had a negative charge for all of the tested conditions.

The role of gluten in a pound cake system: A model approach based on gluten-starch blends.

Science.gov (United States)

Wilderjans, Edith; Pareyt, Bram; Goesaert, Hans; Brijs, Kristof; Delcour, Jan A

2008-10-15

In order to evaluate the role of gluten in cake-making, gluten-starch (GS) blends with different ratios of gluten to starch were tested in a research pound cake formula. The viscosities of batters made from commercial GS blends in the otherwise standardised formula increased with their gluten content. High viscosities during heating provide the batters with the capacity to retain expanding air nuclei, and thereby led to desired product volumes. In line with the above, increasing gluten levels in the cake recipes led to a more extended oven spring period. Cakes with a starch content exceeding 92.5% in the GS blend suffered from substantial collapse during cooling. They had a coarse crumb with a solid gummy layer at the bottom. Image analysis showed statistical differences in numbers of cells per cm(2), cell to total area ratio and mean cell area (pcakes with the lowest density and highest gluten levels. Relative sodium dodecyl sulfate (SDS, 2.0%) buffer (pH 6.8) extractabilities of protein from cakes baked with the different GS blends decreased with gluten content and were strongly correlated with the intensity of collapse. Taken together, the results teach that protein gives the cakes resistance to collapse, resulting in desirable volumes and an optimal grain structure with uniform cell distribution. Copyright © 2008 Elsevier Ltd. All rights reserved.

The rise and fall of gluten!

Science.gov (United States)

Aziz, Imran; Branchi, Federica; Sanders, David S

2015-08-01

Mankind has existed for 2·5 million years but only in the last 10,000 years have we been exposed to wheat. Wheat was first cultivated in the Fertile Crescent (South Western Asia) with a farming expansion that lasted from about 9000BC to 4000BC. Thus it could be considered that wheat (and gluten) is a novel introduction to man's diet! Prior to 1939 the rationing system had already been devised. This led to an imperative to try to increase agricultural production. Thus it was agreed in 1941 that there was a need to establish a Nutrition Society. The very roots of the society were geared towards necessarily increasing the production of wheat. This goal was achieved and by the end of the 20th century, global wheat output had expanded 5-fold. Perhaps as a result the epidemiology of coeliac disease (CD) or gluten sensitive enteropathy has changed. CD is a state of heightened immunological responsiveness to ingested gluten in genetically susceptible individuals. CD now affects 1 % or more of all adults, for which the treatment is a strict lifelong gluten-free diet. However, there is a growing body of evidence to show that a far greater proportion of individuals without coeliac disease are taking a gluten-free diet of their own volition. This clinical entity has been termed non-coeliac gluten sensitivity (NCGS), although the condition is fraught with complexities due to overlap with other gluten-based constituents that can also trigger similar clinical symptoms. This review will explore the relationship between gluten, the rising prevalence of modern coeliac disease, and the new entity of NCGS along with its associated uncertainties.

Gluten-Free Diet Indications, Safety, Quality, Labels, and Challenges

OpenAIRE

Rostami, Kamran; Bold, Justine; Parr, Alison; Johnson, Matt W.

2017-01-01

A gluten-free diet (GFD) is the safest treatment modality in patient with coeliac disease (CD) and other gluten-related disorders. Contamination and diet compliance are important factors behind persistent symptoms in patients with gluten related-disorders, in particular CD. How much gluten can be tolerated, how safe are the current gluten-free (GF) products, what are the benefits and side effects of GFD? Recent studies published in Nutrients on gluten-free products? quality, availability, saf...

Colloid and phosphorus leaching from undisturbed soil cores sampled along a natural clay gradient

DEFF Research Database (Denmark)

Vendelboe, Anders Lindblad; Møldrup, Per; Heckrath, Goswin Johann

2011-01-01

correlated to the accumulated outflow and was described as a diffusion controlled process, using ¾(accumulated outflow). The mass of leached particles was positively correlated to the clay content as well as to water-dispersible colloids. Particulate phosphorus (P) was linearly correlated to concentration......The presence of strongly sorbing compounds in groundwater and tile drains can be a result of colloid-facilitated transport. Colloid and phosphorus leaching from macropores in undisturbed soil cores sampled across a natural clay gradient at Aarup, Denmark, were studied. The aim of the study...... was to correlate easily measurable soil properties, such as clay content and water-dispersible colloids, to colloid and phosphorus leaching. The clay contents across the gradient ranged from 0.11 to 0.23 kg kgj1. Irrigating with artificial rainwater, all samples showed a high first flush of colloids and phosphorus...

On the nature of fibres grown from nanodiamond colloids

Energy Technology Data Exchange (ETDEWEB)

Batsanov, Stepan S., E-mail: batsanov@mail.ru [National Research Institute of Physical-Technical Measurements, Moscow Region (Russian Federation); Guriev, Dmitry L.; Gavrilkin, Sergey M. [National Research Institute of Physical-Technical Measurements, Moscow Region (Russian Federation); Hamilton, Katherine A.; Lindsey, Keith [School of Biological and Biomedical Sciences, Durham University, Durham (United Kingdom); Mendis, Budhika G. [Physics Department, Durham University, Durham (United Kingdom); Riggs, Helen J.; Batsanov, Andrei S. [Chemistry Department, Durham University, Durham (United Kingdom)

2016-04-15

Contrary to earlier assumptions, the fibres spontaneously forming in aqueous colloids of detonation-produced nanodiamond (ND), do not consist purely of ND particles but are agglomerates of the latter with water and/or soft matter of biological (probably fungal) origin, as shown by elemental analysis, IR and Raman spectroscopy, X-ray diffraction, optical refractometry, optical and electron (TEM and ESEM)microscopy, as well as biological staining tests. - Graphical abstract: Fibres spontaneously formed in water colloids of nanodiamond, consist of diamond nanoparticles dispersed in bioorganic matter. - Highlights: • Entangled fibres slowly grow in dilute (∼0.1%) colloids of nanodiamond in water. • Refractive index (∼1.56), electron microscopy and CHN analysis indicate nanodiamond dispersed in organic matter. • Explanation: nanodiamond grains help the growth of fungi which assemble them.

On the nature of fibres grown from nanodiamond colloids

International Nuclear Information System (INIS)

Batsanov, Stepan S.; Guriev, Dmitry L.; Gavrilkin, Sergey M.; Hamilton, Katherine A.; Lindsey, Keith; Mendis, Budhika G.; Riggs, Helen J.; Batsanov, Andrei S.

2016-01-01

Contrary to earlier assumptions, the fibres spontaneously forming in aqueous colloids of detonation-produced nanodiamond (ND), do not consist purely of ND particles but are agglomerates of the latter with water and/or soft matter of biological (probably fungal) origin, as shown by elemental analysis, IR and Raman spectroscopy, X-ray diffraction, optical refractometry, optical and electron (TEM and ESEM)microscopy, as well as biological staining tests. - Graphical abstract: Fibres spontaneously formed in water colloids of nanodiamond, consist of diamond nanoparticles dispersed in bioorganic matter. - Highlights: • Entangled fibres slowly grow in dilute (∼0.1%) colloids of nanodiamond in water. • Refractive index (∼1.56), electron microscopy and CHN analysis indicate nanodiamond dispersed in organic matter. • Explanation: nanodiamond grains help the growth of fungi which assemble them.

Going Gluten-Free: Life with Celiac Disease

Science.gov (United States)

... diagnose it. Diagnosis can often be difficult, as celiac disease symptoms are often similar to those of other conditions. ... of Diabetes and Digestive and Kidney Diseases (NIDDK) Celiac Disease or Gluten Sensitivity? Some of the symptoms of gluten sensitivity (also known as gluten intolerance) ...

Anomalous interactions in confined charge-stabilized colloid

International Nuclear Information System (INIS)

Grier, D G; Han, Y

2004-01-01

Charge-stabilized colloidal spheres dispersed in weak 1:1 electrolytes are supposed to repel each other. Consequently, experimental evidence for anomalous long-ranged like-charged attractions induced by geometric confinement inspired a burst of activity. This has largely subsided because of nagging doubts regarding the experiments' reliability and interpretation. We describe a new class of thermodynamically self-consistent colloidal interaction measurements that confirm the appearance of pairwise attractions among colloidal spheres confined by one or two bounding walls. In addition to supporting previous claims for this as-yet unexplained effect, these measurements also cast new light on its mechanism

Gluten-Free Diet Indications, Safety, Quality, Labels, and Challenges.

Science.gov (United States)

Rostami, Kamran; Bold, Justine; Parr, Alison; Johnson, Matt W

2017-08-08

A gluten-free diet (GFD) is the safest treatment modality in patient with coeliac disease (CD) and other gluten-related disorders. Contamination and diet compliance are important factors behind persistent symptoms in patients with gluten related-disorders, in particular CD. How much gluten can be tolerated, how safe are the current gluten-free (GF) products, what are the benefits and side effects of GFD? Recent studies published in Nutrients on gluten-free products' quality, availability, safety, as well as challenges related to a GFD are discussed.

[Benefits of gluten-free diet: myth or reality?].

Science.gov (United States)

Coattrenec, Yann; Harr, Thomas; Pichard, Claude; Nendaz, Mathieu

2015-10-14

Non celiac gluten sensitivity may explain digestive and general symptoms in patients without celiac disease but this recently described entity is controversial. The role of gluten in comparison to other nutriments such as saccharides and polyols (FODMAPs) remains debated. If a gluten-free diet is clearly indicated in celiac disease and wheat allergy, it remains debatable in non-celiac gluten sensitivity given weak and contradictory evidence. There is no strong evidence for a strict indication to a gluten-free diet in endocrinological, psychiatric, and rheumatologic diseases, or to improve performance in elite sports.

Creation of the first ultra-low gluten barley (Hordeum vulgare L.) for coeliac and gluten-intolerant populations.

Science.gov (United States)

Tanner, Gregory J; Blundell, Malcolm J; Colgrave, Michelle L; Howitt, Crispin A

2016-04-01

Coeliac disease is a well-defined condition that is estimated to affect approximately 1% of the population worldwide. Noncoeliac gluten sensitivity is a condition that is less well defined, but is estimated to affect up to 10% of the population, and is often self-diagnosed. At present, the only remedy for both conditions is a lifelong gluten-free diet. A gluten-free diet is often expensive, high in fat and low in fibre, which in themselves can lead to adverse health outcomes. Thus, there is an opportunity to use novel plant breeding strategies to develop alternative gluten-free grains. In this work, we describe the breeding and characterization of a novel ultra-low gluten (ULG) barley variety in which the hordein (gluten) content was reduced to below 5 ppm. This was achieved using traditional breeding strategies to combine three recessive alleles, which act independently of each other to lower the hordein content in the parental varieties. The grain of the initial variety was shrunken compared to wild-type barleys. We implemented a breeding strategy to improve the grain size to near wild-type levels and demonstrated that the grains can be malted and brewed successfully. The ULG barley has the potential to provide novel healthy foods and beverages for those who require a gluten-free diet. © 2015 The Authors. Plant Biotechnology Journal published by Society for Experimental Biology and The Association of Applied Biologists and John Wiley & Sons Ltd.

Liquid crystal boojum-colloids

International Nuclear Information System (INIS)

Tasinkevych, M; Silvestre, N M; Telo da Gama, M M

2012-01-01

Colloidal particles dispersed in a liquid crystal (LC) lead to distortions of the director field. The distortions are responsible for long-range effective colloidal interactions whose asymptotic behaviour is well understood. The short-distance behaviour depends on the structure and dynamics of the topological defects nucleated near the colloidal particles and a full nonlinear theory is required to describe it. Spherical colloidal particles with strong planar degenerate anchoring nucleate a pair of antipodal surface topological defects, known as boojums. We use the Landau-de Gennes theory to resolve the mesoscopic structure of the boojum cores and to determine the pairwise colloidal interactions. We compare the results in three (3D) and two (2D) spatial dimensions for spherical and disc-like colloidal particles, respectively. The corresponding free energy functionals are minimized numerically using finite elements with adaptive meshes. Boojums are always point-like in 2D, but acquire a rather complex structure in 3D, which depends on the combination of the anchoring potential, the radius of the colloid, the temperature and the LC elastic anisotropy. We identify three types of defect cores in 3D that we call single, double and split-core boojums, and investigate the associated structural transitions. The split-core structure is favoured by low temperatures, strong anchoring and small twist to splay or bend ratios. For sufficiently strong anchoring potentials characterized by a well-defined uniaxial minimum, the split-core boojums are the only stable configuration. In the presence of two colloidal particles, we observe substantial re-arrangements of the inner defects in both 3D and 2D. These re-arrangements lead to qualitative changes in the force-distance profile when compared to the asymptotic quadrupole-quadrupole interaction. In line with the experimental results, the presence of the defects prevents coalescence of the colloidal particles in 2D, but not in 3D

Electro-elastoviscous response of polyaniline functionalized nano-porous zeolite based colloidal dispersions.

Science.gov (United States)

Chattopadhyay, Ankur; Rani, Poonam; Srivastava, Rajendra; Dhar, Purbarun

2018-06-01

The present article discusses the typical influence of grafted conducting polymers in the mesoscale pores of dielectric particles on the static and dynamic electrorheology and electro-viscoelastic behavior of corresponding colloids. Nanocrystalline meso-nanoporous zeolite has been prepared by chemical synthesis and subsequently polyaniline (PANI) coating has been implemented. Electrorheological (ER) suspensions have been formed by dispersing the nanoparticles in silicone oil and their viscoelastic behaviors are examined to understand the nature of such complex colloidal systems under electric fields. PANI-Zeolite ER fluids demonstrate higher static electroviscous effects and yield stress potential than untreated Zeolite, typically studied in literature. Transient electro-viscous characterizations show a stable and negligible hysteresis behavior when both the fluids are exposed to constant as well as time varying electric field intensities. Further oscillatory shear experiments of frequency and strain sweeps exhibit predominant elastic behavior in case of Zeolite based ER suspensions as compared to PANI systems. Detailed investigations reveal Zeolite based ER suspensions display enhanced relative yielding as well as electro-viscoelastic stability than the PANI-Zeolite. The steady state viscous behaviors are scaled against the non-dimensional Mason number to model the system behavior for both fluids. Experimental data of flow behaviors of both the ER fluids are compared with semi-classical models and it is found that the CCJ model possesses a closer proximity than traditional Bingham model, thereby revealing the fluids to be generic pseudo-linear fluids. The present article reveals that while the PANI based fluids are typically hailed superior in literature, it is only restricted to steady shear utilities. In case of dynamic and oscillatory systems, the traditional Zeolite based fluids exhibit superior ER caliber. Copyright © 2018 Elsevier Inc. All rights reserved.

A binomial modeling approach for upscaling colloid transport under unfavorable conditions: Emergent prediction of extended tailing

Science.gov (United States)

Hilpert, Markus; Rasmuson, Anna; Johnson, William P.

2017-07-01

Colloid transport in saturated porous media is significantly influenced by colloidal interactions with grain surfaces. Near-surface fluid domain colloids experience relatively low fluid drag and relatively strong colloidal forces that slow their downgradient translation relative to colloids in bulk fluid. Near-surface fluid domain colloids may reenter into the bulk fluid via diffusion (nanoparticles) or expulsion at rear flow stagnation zones, they may immobilize (attach) via primary minimum interactions, or they may move along a grain-to-grain contact to the near-surface fluid domain of an adjacent grain. We introduce a simple model that accounts for all possible permutations of mass transfer within a dual pore and grain network. The primary phenomena thereby represented in the model are mass transfer of colloids between the bulk and near-surface fluid domains and immobilization. Colloid movement is described by a Markov chain, i.e., a sequence of trials in a 1-D network of unit cells, which contain a pore and a grain. Using combinatorial analysis, which utilizes the binomial coefficient, we derive the residence time distribution, i.e., an inventory of the discrete colloid travel times through the network and of their probabilities to occur. To parameterize the network model, we performed mechanistic pore-scale simulations in a single unit cell that determined the likelihoods and timescales associated with the above colloid mass transfer processes. We found that intergrain transport of colloids in the near-surface fluid domain can cause extended tailing, which has traditionally been attributed to hydrodynamic dispersion emanating from flow tortuosity of solute trajectories.

Starch Characteristics Linked to Gluten-Free Products

Directory of Open Access Journals (Sweden)

Stefan W. Horstmann

2017-04-01

Full Text Available The increasing prevalence of coeliac disease (CD and gluten-related disorders has led to increasing consumer demand for gluten-free products with quality characteristics similar to wheat bread. The replacement of gluten in cereal-based products remains a challenge for scientists, due to its unique role in network formation, which entraps air bubbles. When gluten is removed from a flour, starch is the main component left. Starch is used as gelling, thickening, adhesion, moisture-retention, stabilizing, film forming, texturizing and anti-staling ingredient. The extent of these properties varies depending on the starch source. The starches can additionally be modified increasing or decreasing certain properties of the starch, depending on the application. Starch plays an important role in the formulation of bakery products and has an even more important role in gluten-free products. In gluten-free products, starch is incorporated into the food formulation to improve baking characteristics such as the specific volume, colour and crumb structure and texture. This review covers a number of topics relating to starch; including; an overview of common and lesser researched starches; chemical composition; morphology; digestibility; functionality and methods of modification. The emphasis of this review is on starch and its properties with respect to the quality of gluten-free products.

Starch Characteristics Linked to Gluten-Free Products.

Science.gov (United States)

Horstmann, Stefan W; Lynch, Kieran M; Arendt, Elke K

2017-04-06

The increasing prevalence of coeliac disease (CD) and gluten-related disorders has led to increasing consumer demand for gluten-free products with quality characteristics similar to wheat bread. The replacement of gluten in cereal-based products remains a challenge for scientists, due to its unique role in network formation, which entraps air bubbles. When gluten is removed from a flour, starch is the main component left. Starch is used as gelling, thickening, adhesion, moisture-retention, stabilizing, film forming, texturizing and anti-staling ingredient. The extent of these properties varies depending on the starch source. The starches can additionally be modified increasing or decreasing certain properties of the starch, depending on the application. Starch plays an important role in the formulation of bakery products and has an even more important role in gluten-free products. In gluten-free products, starch is incorporated into the food formulation to improve baking characteristics such as the specific volume, colour and crumb structure and texture. This review covers a number of topics relating to starch; including; an overview of common and lesser researched starches; chemical composition; morphology; digestibility; functionality and methods of modification. The emphasis of this review is on starch and its properties with respect to the quality of gluten-free products.

Gluten sensitivity and neurological manifestations

Directory of Open Access Journals (Sweden)

Agostino Berio

2015-12-01

Full Text Available The authors report on six cases of gluten-sensitivity, also defined non-celiac gluten sensitivity, characterized by abdominal features (diarrhea, bloating, pain, genetic positivity for predisposition to celiac disease (DQB1* 02 in all cases; DQA1*05 in three; DQA1*02 in two, DQB1*03 in two, negative anti-t-Transglutaminase antibodies, normal mucosa on biopsy in four cases, type 1 of Marsh in one case. The subjects presented frequent central nervous system (CNS symptoms: headache in three patients, somnolence in one, electroencephalogram aspecific alterations in three (in two of them with previous seizures, leptomeningeal cyst in one, intracranial calcification in one, cerebral gliosis in two. After a gluten-free diet, all intestinal and clinical CNS features remitted, but re-appeared after gluten reintroduction. On the basis of the neurological signs, the authors stress the relevance of immune innate system in the pathogenesis of these cases with possible subsequent evolution on immune adaptive system involvement.

The Effects of Reduced Gluten Barley Diet on Humoral and Cell-Mediated Systemic Immune Responses of Gluten-Sensitive Rhesus Macaques

Directory of Open Access Journals (Sweden)

Karol Sestak

2015-03-01

Full Text Available Celiac disease (CD affects approximately 1% of the general population while an estimated additional 6% suffers from a recently characterized, rapidly emerging, similar disease, referred to as non-celiac gluten sensitivity (NCGS. The only effective treatment of CD and NCGS requires removal of gluten sources from the diet. Since required adherence to a gluten-free diet (GFD is difficult to accomplish, efforts to develop alternative treatments have been intensifying in recent years. In this study, the non-human primate model of CD/NCGS, e.g., gluten-sensitive rhesus macaque, was utilized with the objective to evaluate the treatment potential of reduced gluten cereals using a reduced gluten (RG; 1% of normal gluten barley mutant as a model. Conventional and RG barleys were used for the formulation of experimental chows and fed to gluten-sensitive (GS and control macaques to determine if RG barley causes a remission of dietary gluten-induced clinical and immune responses in GS macaques. The impacts of the RG barley diet were compared with the impacts of the conventional barley-containing chow and the GFD. Although remission of the anti-gliadin antibody (AGA serum responses and an improvement of clinical diarrhea were noted after switching the conventional to the RG barley diet, production of inflammatory cytokines, e.g., interferon-gamma (IFN-γ, tumor necrosis factor (TNF and interleukin-8 (IL-8 by peripheral CD4+ T helper lymphocytes, persisted during the RG chow treatment and were partially abolished only upon re-administration of the GFD. It was concluded that the RG barley diet might be used for the partial improvement of gluten-induced disease but its therapeutic value still requires upgrading—by co-administration of additional treatments.

The effects of reduced gluten barley diet on humoral and cell-mediated systemic immune responses of gluten-sensitive rhesus macaques.

Science.gov (United States)

Sestak, Karol; Thwin, Hazel; Dufour, Jason; Aye, Pyone P; Liu, David X; Moehs, Charles P

2015-03-06

Celiac disease (CD) affects approximately 1% of the general population while an estimated additional 6% suffers from a recently characterized, rapidly emerging, similar disease, referred to as non-celiac gluten sensitivity (NCGS). The only effective treatment of CD and NCGS requires removal of gluten sources from the diet. Since required adherence to a gluten-free diet (GFD) is difficult to accomplish, efforts to develop alternative treatments have been intensifying in recent years. In this study, the non-human primate model of CD/NCGS, e.g., gluten-sensitive rhesus macaque, was utilized with the objective to evaluate the treatment potential of reduced gluten cereals using a reduced gluten (RG; 1% of normal gluten) barley mutant as a model. Conventional and RG barleys were used for the formulation of experimental chows and fed to gluten-sensitive (GS) and control macaques to determine if RG barley causes a remission of dietary gluten-induced clinical and immune responses in GS macaques. The impacts of the RG barley diet were compared with the impacts of the conventional barley-containing chow and the GFD. Although remission of the anti-gliadin antibody (AGA) serum responses and an improvement of clinical diarrhea were noted after switching the conventional to the RG barley diet, production of inflammatory cytokines, e.g., interferon-gamma (IFN-γ), tumor necrosis factor (TNF) and interleukin-8 (IL-8) by peripheral CD4+ T helper lymphocytes, persisted during the RG chow treatment and were partially abolished only upon re-administration of the GFD. It was concluded that the RG barley diet might be used for the partial improvement of gluten-induced disease but its therapeutic value still requires upgrading-by co-administration of additional treatments.

Non-celiac gluten hypersensitivity

DEFF Research Database (Denmark)

Husby, Steffen; Murray, Joseph

2015-01-01

used double-blind placebo-controlled food challenges (DBPCFCs) for the diagnosis of NCGS, and none in children. Innate immune reactivity to amylase trypsin inhibitors has been suggested as the pathogenic principle in NCGS, but confirmatory evidence is lacking. Also, further clinical studies including...... transglutaminase 2, characteristic histological abnormalities of the small intestine, and an almost obligatory genetic haplotype (HLA-DQ2 or DQ8). The diagnosis of NCGS is based largely on the clinical suspicion of hyper-reactivity to gluten and the absence of the characteristics of CD. Few published studies have......Non-celiac gluten sensitivity (NCGS) has been introduced recently as a potentially common disease on the basis of studies of patients with claimed reactivity to gluten but without the characteristics of celiac disease (CD). CD is characterized by antibody reactivity toward the autoantigen...

Magnetoresponsive conductive colloidal suspensions with magnetized carbon nanotubes

Energy Technology Data Exchange (ETDEWEB)

Abdalla, Ahmed M. [Department of Engineering Physics, McMaster University, 1280 Main Street West, Hamilton, Ontario, Canada L8S 4L7 (Canada); Abdel Fattah, Abdel Rahman [Department of Mechanical Engineering, McMaster University, 1280 Main Street West, Hamilton, Ontario, Canada L8S 4L7 (Canada); Ghosh, Suvojit [Department of Engineering Physics, McMaster University, 1280 Main Street West, Hamilton, Ontario, Canada L8S 4L7 (Canada); Puri, Ishwar K., E-mail: ikpuri@mcmaster.ca [Department of Engineering Physics, McMaster University, 1280 Main Street West, Hamilton, Ontario, Canada L8S 4L7 (Canada); Department of Mechanical Engineering, McMaster University, 1280 Main Street West, Hamilton, Ontario, Canada L8S 4L7 (Canada)

2017-01-01

We synthesize a novel and hitherto unreported class of colloidal suspensions for which the dispersed phase, which consists of multiwall carbon nanotubes (MWNTs) decorated with magnetic nanoparticles (MNPs), is both magnetoresponsive and electrically conductive. Synthesis of the dispersed phase merges processes for producing ferrofluids and magnetic MWNTs (mMWNTs). We explore means to tune the properties of these magnetic conductive colloids (MCCs) by varying the (1) MNP material composition, and (2) MNP:MWNT (w/w) magnetization weight ratio (γ). The mMWNTs are examined using XRD, TEM, EDX and SQUID and MCCs are by measuring their zeta potential and electric conductivity. Magnetite (Fe{sub 3}O{sub 4}) MNPs, which possess a high Curie temperature, produce mMWNTs with high saturation magnetization that respond relatively weakly to temperature variations. Mn{sub 0.2}Cu{sub 0.2}Zn{sub 0.6}Fe{sub 2}O{sub 4} and Cu{sub 0.4}Zn{sub 0.6}Fe{sub 2}O{sub 4} MNPs with lower Curie temperatures are more sensitive to changing temperature. Increasing the MNP Cu content improves the electric conductivity of the corresponding MCC while increasing γ enhances its magnetic response. After γ is raised above a threshold value, mMWNT decoration on the CNT surface becomes nonuniform since the MNPs now agglomerate perpendicular to the nanotube surface. These colloidal suspensions are a promising new class of material that can be manipulated with a magnetic field to tune their electrical conductivity. - Highlights: ●We synthesize a novel and hitherto unreported class of colloidal suspensions. ●These colloidal suspensions are both magnetoresponsive and electrically conductive. ●The dispersed phase consists of MWNTs decorated with different magnetic nanoparticles. ●These colloids have enhanced magnetic response and electric conductivity (up to 169.5 mS cm{sup −1}). ●It is a promising new class of material that can be manipulated with a magnetic field.

Effect of pentosans on gluten formation and properties.

NARCIS (Netherlands)

Wang, M.

2003-01-01

Keywords: pentosans, gluten yield, gluten properties, glutenin macropolymerThe gluten protein polymeric network plays a pivotal role in determining the end-use quality of wheat in many food products. The properties of this polymeric network are strongly affected by wheat flour

[Irritable bowel syndrome, celiac disease and gluten].

Science.gov (United States)

Mearin, Fermín; Montoro, Miguel

2014-08-04

For many years irritable bowel syndrome (IBS) and celiac disease (CD) have been considered 2 completely separate entities, with CD being clearly related to a permanent gluten intolerance and IBS having no relation with gluten ingestion. However IBS and CD symptoms may be indistinguishable, especially when diarrhea, bloating or abdominal pain predominate. In the last decade several studies have shown that the separation between CD and IBS is not so clear. Thus, some patients who have been diagnosed of IBS suffer in fact from CD. In addition, it seems that there is a group of patients who, without having CD, suffer gluten intolerance that cause them digestive symptoms similar to those of IBS. Gluten sensitivity is defined as the spectrum of morphological, immunological and functional abnormalities that respond to a gluten-free diet. This concept includes histological, immunological and clinical manifestations in the absence of evident morphological abnormalities. Therefore, it is mandatory to establish in a scientific way in which patients a gluten-free diet will be beneficial as well as when this is not justified. Copyright © 2013 Elsevier España, S.L. All rights reserved.

Non-celiac gluten sensitivity: people without celiac disease avoiding gluten-is it due to histamine intolerance?

Science.gov (United States)

Schnedl, Wolfgang J; Lackner, Sonja; Enko, Dietmar; Schenk, Michael; Mangge, Harald; Holasek, Sandra J

2018-04-01

Food intolerance/malabsorption is caused by food ingredients, carbohydrates (mainly lactose and fructose), proteins (gluten), and biogenic amines (histamine) which cause nonspecific gastrointestinal and extra-intestinal symptoms. Here we focus on possible etiologic factors of intolerance/malabsorption especially in people with non-celiac gluten sensitivity (NCGS) or the so-called people without celiac disease avoiding gluten (PWCDAG) and histamine intolerance. Recognizing the recently described symptoms of NCGS (PWCDAG) we review correlations and parallels to histamine intolerance (HIT). We show that intestinal and extra-intestinal NCGS (PWCDAG) symptoms are very similar to those which can be found in histamine intolerance. After a detailed diagnostic workup for all possible etiologic factors in every patient, a targeted dietary intervention for single or possibly combined intolerance/malabsorption might be more effective than a short-term diet low in fermentable oligo-, di- and monosaccharides and polyols (FODMAP) or the untargeted uncritical use of gluten-free diets.

Sustainable steric stabilization of colloidal titania nanoparticles

Science.gov (United States)

Elbasuney, Sherif

2017-07-01

A route to produce a stable colloidal suspension is essential if mono-dispersed particles are to be successfully synthesized, isolated, and used in subsequent nanocomposite manufacture. Dispersing nanoparticles in fluids was found to be an important approach for avoiding poor dispersion characteristics. However, there is still a great tendency for colloidal nanoparticles to flocculate over time. Steric stabilization can prevent coagulation by introducing a thick adsorbed organic layer which constitutes a significant steric barrier that can prevent the particle surfaces from coming into direct contact. One of the main features of hydrothermal synthesis technique is that it offers novel approaches for sustainable nanoparticle surface modification. This manuscript reports on the sustainable steric stabilization of titanium dioxide nanoparticles. Nanoparticle surface modification was performed via two main approaches including post-synthesis and in situ surface modification. The tuneable hydrothermal conditions (i.e. temperature, pressure, flow rates, and surfactant addition) were optimized to enable controlled steric stabilization in a continuous fashion. Effective post synthesis surface modification with organic ligand (dodecenyl succinic anhydride (DDSA)) was achieved; the optimum surface coating temperature was reported to be 180-240 °C to ensure DDSA ring opening and binding to titania nanoparticles. Organic-modified titania demonstrated complete change in surface properties from hydrophilic to hydrophobic and exhibited phase transfer from the aqueous phase to the organic phase. Exclusive surface modification in the reactor was found to be an effective approach; it demonstrated surfactant loading level 2.2 times that of post synthesis surface modification. Titania was also stabilized in aqueous media using poly acrylic acid (PAA) as polar polymeric dispersant. PAA-titania nanoparticles demonstrated a durable amorphous polymeric layer of 2 nm thickness. This

Self-Supporting Nanodiamond Gels: Elucidating Colloidal Interactions Through Rheology_

Science.gov (United States)

Adhikari, Prajesh; Tripathi, Anurodh; Vogel, Nancy A.; Rojas, Orlando J.; Raghavan, Sriunivasa R.; Khan, Saad A.

This work investigates the colloidal interactions and rheological behavior of nanodiamond (ND) dispersions. While ND represents a promising class of nanofiller due to its high surface area, superior mechanical strength, tailorable surface functionality and biocompatibility, much remains unknown about the behavior of ND dispersions. We hypothesize that controlling interactions in ND dispersions will lead to highly functional systems with tunable modulus and shear response. Steady and dynamic rheology techniques are thus employed to systematically investigate nanodiamonds dispersed in model polar and non-polar media. We find that low concentrations of ND form gels almost instantaneously in a non-polar media. In contrast, ND's in polar media show a time-dependent behavior with the modulus increasing with time. We attribute the difference in behavior to variations in inter-particle interactions as well as the interaction of the ND with the media. Large steady and oscillatory strains are applied to ND colloidal gels to investigate the role of shear in gel microstructure breakdown and recovery. For colloidal gels in non-polar medium, the incomplete recovery of elastic modulus at high strain amplitudes indicates dominance of particle-particle interactions; however, in polar media the complete recovery of elastic modulus even at high strain amplitudes indicates dominance of particle-solvent interactions. These results taken together provide a platform to develop self-supporting gels with tunable properties in terms of ND concentration, and solvent type.

Colloid electrochemistry of conducting polymer: towards potential-induced in-situ drug release

International Nuclear Information System (INIS)

Sankoh, Supannee; Vagin, Mikhail Yu.; Sekretaryova, Alina N.; Thavarungkul, Panote; Kanatharana, Proespichaya; Mak, Wing Cheung

2017-01-01

Highlights: • Pulsed electrode potential induced an in-situ drug release from dispersion of conducting polymer microcapsules. • Fast detection of the released drug within the colloid microenvironment. • Improved the efficiency of localized drug release at the electrode interface. - Abstract: Over the past decades, controlled drug delivery system remains as one of the most important area in medicine for various diseases. We have developed a new electrochemically controlled drug release system by combining colloid electrochemistry and electro-responsive microcapsules. The pulsed electrode potential modulation led to the appearance of two processes available for the time-resolved registration in colloid microenvironment: change of the electronic charge of microparticles (from 0.5 ms to 0.1 s) followed by the drug release associated with ionic equilibration (1–10 s). The dynamic electrochemical measurements allow the distinction of drug release associated with ionic relaxation and the change of electronic charge of conducting polymer colloid microparticles. The amount of released drug (methylene blue) could be controlled by modulating the applied potential. Our study demonstrated a surface-potential driven controlled drug release of dispersion of conducting polymer carrier at the electrode interfaces, while the bulk colloids dispersion away from the electrode remains as a reservoir to improve the efficiency of localized drug release. The developed new methodology creates a model platform for the investigations of surface potential-induced in-situ electrochemical drug release mechanism.

RHEOLOGICAL CHARACTERISTICS OF GLUTEN-FREE DOUGH

Directory of Open Access Journals (Sweden)

Iva Burešová

2014-02-01

Full Text Available Dynamic oscillation rheometry was used to determine the viscoelastic properties of gluten-free dough prepared from amaranth, chickpea, millet, corn, quinoa, buckwheat and rice flours. The viscoelastic properties was described by storage modulus G´, loss modulus G´´ and phase angle tg(δ. The relationship between viscoelastic properties of gluten-free dough and bread-making quality was evaluated. The results of this study indicated that dynamic oscillation rheometry may be used to differentiate the bread-making quality of gluten-free flour. Bread-making quality of gluten-free flour is the best characterised by curve slope of storage modulus G´and phase angle tg(δ while bread made from the flour with storage modulus and phase angle with non-linear slope in low deformation frequencies 0.01–0.10 Hz achieved the largest volume.

Applying Simulation Method in Formulation of Gluten-Free Cookies

Directory of Open Access Journals (Sweden)

Nikitina Marina

2017-01-01

Full Text Available At present time priority direction in the development of new food products its developing of technology products for special purposes. These types of products are gluten-free confectionery products, intended for people with celiac disease. Gluten-free products are in demand among consumers, it needs to expand assortment, and improvement of quality indicators. At this article results of studies on the development of pastry products based on amaranth flour does not contain gluten. Study based on method of simulation recipes gluten-free confectionery functional orientation to optimize their chemical composition. The resulting products will allow to diversify and supplement the necessary nutrients diet for people with gluten intolerance, as well as for those who follow a gluten-free diet.

Linear Optical Properties of Gold Colloid

Directory of Open Access Journals (Sweden)

Jingmin XIA

2015-11-01

Full Text Available Gold colloid was prepared by reducing HAuCl4·4H2O with Na3C6H5O7·2H2O. The morphology, size of gold nanoparticles and the optical property of colloid were characterized by transmission electron microscope and UV-Vis spectrophotometer, respectively. It shows that the gold nanoparticles are in the shape of spheres with diameters less than 8 nm, and the surface plasmon resonance absorption peak is located at about 438 nm. As the volume fraction of gold particles increases, the intensity of absorption peak strengthens. The optical property of gold colloid was analyzed by Maxwell-Garnett (MG effective medium theory in the company of Drude dispersion model. The results show that the matrix dielectric constant is a main factor, which influences the optical property of gold colloid.DOI: http://dx.doi.org/10.5755/j01.ms.21.4.9558

Functionality of alternative protein in gluten-free product development.

Science.gov (United States)

Deora, Navneet Singh; Deswal, Aastha; Mishra, Hari Niwas

2015-07-01

Celiac disease is an immune-mediated disease triggered in genetically susceptible individuals by ingested gluten from wheat, rye, barley, and other closely related cereal grains. The current treatment for celiac disease is life-long adherence to a strict gluten-exclusion diet. The replacement of gluten presents a significant technological challenge, as it is an essential structure-building protein, which is necessary for formulating high-quality baked goods. A major limitation in the production of gluten-free products is the lack of protein functionality in non-wheat cereals. Additionally, commercial gluten-free mixes usually contain only carbohydrates, which may significantly limit the amount of protein in the diet. In the recent past, various approaches are attempted to incorporate protein-based ingredients and to modify the functional properties for gluten-free product development. This review aims to the highlight functionality of the alternative protein-based ingredients, which can be utilized for gluten-free product development both functionally as well as nutritionally. © The Author(s) 2014.

Celiac disease and non-celiac gluten sensitivity

Science.gov (United States)

Lebwohl, Benjamin; Ludvigsson, Jonas F

2015-01-01

Celiac disease is a multisystem immune based disorder that is triggered by the ingestion of gluten in genetically susceptible individuals. The prevalence of celiac disease has risen in recent decades and is currently about 1% in most Western populations. The reason for this rise is unknown, although environmental factors related to the hygiene hypothesis are suspected. The pathophysiology of celiac disease involves both the innate and adaptive immune response to dietary gluten. Clinical features are diverse and include gastrointestinal symptoms, metabolic bone disease, infertility, and many other manifestations. Although a gluten-free diet is effective in most patients, this diet can be burdensome and can limit quality of life; consequently, non-dietary therapies are at various stages of development. This review also covers non-celiac gluten sensitivity. The pathophysiology of this clinical phenotype is poorly understood, but it is a cause of increasing interest in gluten-free diets in the general population. PMID:26438584

Deposition of bi-dispersed particles in inkjet-printed evaporating colloidal drops

Science.gov (United States)

Sun, Ying; Joshi, Abhijit; Chhasatia, Viral

2010-11-01

In this study, the deposition behaviors of inkjet-printed evaporating colloidal drops consisting of bi-dispersed micro and nano-sized particles are investigated by fluorescence microscopy and SEM. The results on hydrophilic glass substrates show that, evaporatively-driven outward flow drives the nanoparticles to deposit close to the pinned contact line while an inner ring deposition is formed by microparticles. This size-induced particle separation is consistent with the existence of a wedge-shaped drop edge near the contact line region of an evaporating drop on a hydrophilic substrate. The replenishing evaporatively-driven flow assembles nanoparticles closer to the pinned contact line forming an outer ring of nanoparticles and this particle jamming further enhances the contact line pinning. Microparticles are observed to form an inner ring inside the nano-sized deposits. This size-induced particle separation presents a new challenge to the uniformity of functional materials in bioprinting applications where nanoparticles and micro-sized cells are mixed together. On the other hand, particle self-assembly based on their sizes provides enables easy and well-controlled pattern formation. The effects of particle size contrast, particle volume fraction, substrate surface energy, and relative humidity of the printing environment on particle separation are examined in detail.

Non-celiac gluten sensitivity: Time for sifting the grain

Science.gov (United States)

Elli, Luca; Roncoroni, Leda; Bardella, Maria Teresa

2015-01-01

In the last few years, a new nomenclature has been proposed for the disease induced by the ingestion of gluten, a protein present in wheat, rice, barley and oats. Besides celiac disease and wheat allergy, the most studied forms of gluten-related disorders characterized by an evident immune mechanism (autoimmune in celiac disease and IgE-mediated in wheat allergy), a new entity has been included, apparently not driven by an aberrant immune response: the non-celiac gluten sensitivity (NCGS). NCGS is characterized by a heterogeneous clinical picture with intestinal and extraintestinal symptoms arising after gluten ingestion and rapidly improving after its withdrawal from the diet. The pathogenesis of NCGS is largely unknown, but a mixture of factors such as the stimulation of the innate immune system, the direct cytotoxic effects of gluten, and probably the synergy with other wheat molecules, are clues for the complicated puzzle. In addition, the diagnostic procedures still remain problematic due to the absence of efficient diagnostic markers; thus, diagnosis is based upon the symptomatic response to a gluten-free diet and the recurrence of symptoms after gluten reintroduction with the possibility of an important involvement of a placebo effect. The temporary withdrawal of gluten seems a reasonable therapy, but the timing of gluten reintroduction and the correct patient management approach are have not yet been determined. PMID:26217073

Colloid transport in dual-permeability media

Science.gov (United States)

Leij, Feike J.; Bradford, Scott A.

2013-07-01

It has been widely reported that colloids can travel faster and over longer distances in natural structured porous media than in uniform structureless media used in laboratory studies. The presence of preferential pathways for colloids in the subsurface environment is of concern because of the increased risks for disease caused by microorganisms and colloid-associated contaminants. This study presents a model for colloid transport in dual-permeability media that includes reversible and irreversible retention of colloids and first-order exchange between the aqueous phases of the two regions. The model may also be used to describe transport of other reactive solutes in dual-permeability media. Analytical solutions for colloid concentrations in aqueous and solid phases were obtained using Laplace transformation and matrix decomposition. The solutions proved convenient to assess the effect of model parameters on the colloid distribution. The analytical model was used to describe effluent concentrations for a bromide tracer and 3.2- or 1-μm-colloids that were observed after transport through a composite 10-cm long porous medium made up of a cylindrical lens or core of sand and a surrounding matrix with sand of a different grain size. The tracer data were described very well and realistic estimates were obtained for the pore-water velocity in the two flow domains. An accurate description was also achieved for most colloid breakthrough curves. Dispersivity and retention parameters were typically greater for the larger 3.2-μm-colloids while both reversible and irreversible retention rates tended to be higher for the finer sands than the coarser sand. The relatively small sample size and the complex flow pattern in the composite medium made it difficult to reach definitive conclusions regarding transport parameters for colloid transport.

Reduced-Gliadin Wheat Bread: An Alternative to the Gluten-Free Diet for Consumers Suffering Gluten-Related Pathologies

Science.gov (United States)

Gil-Humanes, Javier; Pistón, Fernando; Altamirano-Fortoul, Rossana; Real, Ana; Comino, Isabel; Sousa, Carolina; Rosell, Cristina M.; Barro, Francisco

2014-01-01

Wheat flour cannot be tolerated by those who suffer allergies to gluten. Human pathologies associated with grain proteins have increased worldwide in recent years, and the only effective treatment available is a lifelong gluten-free diet, which is complicated to follow and detrimental to gut health. This manuscript describes the development of wheat bread potentially suitable for celiac patients and other gluten-intolerant individuals. We have made bread using wheat flour with very low content of the specific gluten proteins (near gliadin-free) that are the causal agents for pathologies such as celiac disease. Loaves were compared with normal wheat breads and rice bread. Organoleptic, nutritional, and immunotoxic properties were studied. The reduced-gliadin breads showed baking and sensory properties, and overall acceptance, similar to those of normal flour, but with up to 97% lower gliadin content. Moreover, the low-gliadin flour has improved nutritional properties since its lysine content is significantly higher than that of normal flour. Conservative estimates indicate that celiac patients could safely consume 67 grams of bread per day that is made with low-gliadin flour. However, additional studies, such as feeding trials with gluten-intolerant patients, are still needed in order to determine whether or not the product can be consumed by the general celiac population, as well as the actual tolerated amount that can be safely ingested. The results presented here offer a major opportunity to improve the quality of life for millions of sufferers of gluten intolerance throughout the world. PMID:24621595

THE INFLUENCE OF GLUTEN - FREE FLOURS ON THE QUALITY INDICATORS OF BISCUIT SEMI - FINISHED PRODUCTS

Directory of Open Access Journals (Sweden)

К. G. IORGACHOVA

2016-12-01

Full Text Available The article is devoted to the research of applicability of gluten-free flours from cereal crops and from by-products of cereal crop processing - ground crumbs sifted out in a process of flake production from rice, corn and millet during the production of biscuit semi-finished products. Taking into account that viscosity is an important technological characteristic of foam-like biscuit dough, as it determines foam strength and dispersed medium stability, the influence of gluten-free flours on the structural and rheological properties of biscuit dough was studied. It is determined that the substitution of wheat flour for cereal flours leads to viscosity reduction of the dough as a consequence of absence of gluten-forming proteins in them. A comparative analysis of changes in viscous properties of biscuit dough based on flour from flakes crumb while warming it up to 60°C with dough based on cereal flours and dough based on wheat flour was held. It is shown that the presence of partially gelatinized starch granules in flour from flake crumb, as a result of technological peculiarities of their extraction, promotes greater demonstration of thickening properties already at the initial stage of baking than in cereal flours. This leads to an increase of dough viscosity and formation of desired rheological characteristics, which provide the porous structure of finished products. To provide the high quality of gluten-free biscuit semi-finished products, the recipe composition of gluten-free biscuit semi-finished product, based on flour mixture from millet flakes crumb, corn and rice flour, was optimized by using the method of mathematical design of experiments.  The porosity indicator was chosen as the criteria for the evaluation of influence of proportion of gluten-free flours on the quality of biscuit semi-finished products. The response surfaces of dependency of biscuit porosity from mass ratio of recipe components in the composite mixture were

Long-term Effects of Organic Waste Fertilizers on Soil Structure, Tracer Transport, and Leaching of Colloids.

Science.gov (United States)

Lekfeldt, Jonas Duus Stevens; Kjaergaard, Charlotte; Magid, Jakob

2017-07-01

Organic waste fertilizers have previously been observed to significantly affect soil organic carbon (SOC) content and soil structure. However, the effect of organic waste fertilizers on colloid dispersibility and leaching of colloids from topsoil has not yet been studied extensively. We investigated how the repeated application of different types of agricultural (liquid cattle slurry and solid cattle manure) and urban waste fertilizers (sewage sludge and composted organic household waste) affected soil physical properties, colloid dispersion from aggregates, tracer transport, and colloid leaching from intact soil cores. Total porosity was positively correlated with SOC content. Yearly applications of sewage sludge increased absolute microporosity (pores 30 μm) compared with the unfertilized control, whereas organic household waste compost fertilization increased both total porosity and the absolute porosity in all pore size classes (though not significant for 100-600 μm). Treatments receiving large amounts of organic fertilizers exhibited significantly lower levels of dispersible colloids compared with an unfertilized control and a treatment that had received moderate applications of cattle slurry. The content of water-dispersible colloids could not be explained by a single factor, but differences in SOC content, electrical conductivity, and sodium adsorption ratio were important factors. Moreover, we found that the fertilizer treatments did not significantly affect the solute transport properties of the topsoil. Finally, we found that the leaching of soil colloids was significantly decreased in treatments that had received large amounts of organic waste fertilizers, and we ascribe this primarily to treatment-induced differences in effluent electrical conductivity during leaching. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

Colloid cyst in pituitary gland: a case report

International Nuclear Information System (INIS)

Koo, Hee Youn; Lee, Myung Jun; Lee, Chang Joon; Yoo, Jeong Hyun

2001-01-01

Colloid cyst is a congenital lesion which is thought to be derived from the primitive neuro epithelium, and is most frequently located in the anterior half of the third ventricle. Colloid cysts rarely occur in the pituitary gland, and we describe a case of pituitary colloid cyst, including the CT, MRI and pathologic findings

Gluten-free diet and the possibility of enriching the diet coeliacs

OpenAIRE

BLAŽKOVÁ, Klára

2014-01-01

This thesis deals with the gluten-free diet and its possible enrichment. It is divided into two parts. The first part includes chapters such as history of gluten-free diet, basics of a gluten free diet, the first step in the introduction of a gluten-free diet, gluten-free food labeling legislation and the use of alcohol on a gluten-free diet. The practical part is focused on enriching the diet celiac patients. I focused on the preparation of bakery products for celiac, I have designed and pra...

Catering Gluten-Free When Simultaneously Using Wheat Flour.

Science.gov (United States)

Miller, Kathryn; McGough, Norma; Urwin, Heidi

2016-02-01

A European law on gluten-free (GF) labeling came into force in 2012, covering foods sold prepacked and in food service establishments, and a similar U.S. Food and Drug Administration (FDA) regulation covers GF labeling from August 2014. Gluten is found in the grains wheat, rye, and barley. A common source of gluten in the kitchen is wheat flour. This research aimed to determine variables that have a significant effect on gluten contamination in commercial kitchens when wheat flour is in use and to establish controls necessary to assure GF production. A pilot study was used to test the following hypotheses: (i) increasing duration of exposure to wheat flour would increase gluten contamination, (ii) increasing distance between the site of preparation and the site of wheat flour would reduce gluten contamination, (iii) the use of a ventilation hood would decrease gluten contamination, and (iv) the use of a barrier segregating the site of preparation of a GF meal and the use of wheat flour would decrease gluten contamination. Petri dishes containing GF rice pudding were placed in three directions at increasing distances (0.5 to 2 m) from a site of wheat flour use. A barrier was in place between a third of samples and the site of wheat flour. After wheat flour was handled for 0.5 and 4.0 h, petri dishes were sealed and the contents were analyzed for gluten. The experiment was duplicated with the ventilation hood on and off. The pilot study revealed that a distance of 2 m from the use of wheat flour was required to control gluten contamination at ≤20 ppm if wheat flour had been in use for 4.0 h. The identified control of distance was tested in five different study sites. In each of the study sites, a test meal was prepared a minimum of 2 m away from the site of wheat flour use. Although kitchens vary and must be considered individually, the established control of a minimum 2 m distance, along with good hygiene practices, was found to be effective in preparing GF meals

Gluten sensitivity in patients with IgA nephropathy.

Science.gov (United States)

Smerud, Hilde Kloster; Fellström, Bengt; Hällgren, Roger; Osagie, Sonia; Venge, Per; Kristjánsson, Gudjón

2009-08-01

Coeliac disease is more frequent in IgA nephropathy (IgAN) patients compared to the healthy population. Several hypotheses postulate that food antigens like gluten may be involved in the onset of IgAN. In this study, we used a recently developed mucosal patch technique to evaluate the rectal mucosal inflammatory reaction to gluten in patients with IgAN (n = 27) compared to healthy subjects (n = 18). The rectal mucosal production of nitric oxide (NO) and release of myeloperoxidase (MPO) and eosinophil cationic protein (ECP) were measured. Serum samples were analysed for IgA and IgG antigliadin antibodies (AGA), IgA antibodies against tissue transglutaminase and IgA endomysium antibodies. Gluten reactivity, defined as increase in MPO and/or NO after gluten exposure, was observed in 8 of 27 IgAN patients. The prevalence of HLA-DQ2 and DQ8 was not increased among gluten-sensitive patients, and the total prevalence among IgAN patients was the same as for the normal population. An elevated serum IgA AGA response was seen in 9 of 27 IgAN patients. The increase in IgA AGA did not correlate with the gluten sensitivity as measured by NO and/or MPO. A specific serum IgG AGA response was seen in one patient only. Antibodies against tissue transglutaminase and endomysium were not observed. It is concluded that approximately one-third of our IgAN patients have a rectal mucosal sensitivity to gluten, but without signs of coeliac disease, and we hypothesize that such sub-clinical inflammation to gluten might be involved in the pathogenesis of IgAN in a subgroup of patients.

Lysine-functionalized nanodiamonds as gene carriers: development of stable colloidal dispersion for in vitro cellular uptake studies and siRNA delivery application

Directory of Open Access Journals (Sweden)

Alwani S

2016-02-01

Full Text Available Saniya Alwani,1 Randeep Kaur,1 Deborah Michel,1 Jackson M Chitanda,2 Ronald E Verrall,3 Chithra Karunakaran,4 Ildiko Badea1 1Drug Design and Discovery Research Group, College of Pharmacy and Nutrition, 2Department of Chemical & Biological Engineering, 3Department of Chemistry, University of Saskatchewan, 4Canadian Light Source, Saskatoon, SK, Canada Purpose: Nanodiamonds (NDs are emerging as an attractive tool for gene therapeutics. To reach their full potential for biological application, NDs should maintain their colloidal stability in biological milieu. This study describes the behavior of lysine-functionalized ND (lys-ND in various dispersion media, with an aim to limit aggregation and improve the colloidal stability of ND-gene complexes called diamoplexes. Furthermore, cellular and macromolecular interactions of lys-NDs are also analyzed in vitro to establish the understanding of ND-mediated gene transfer in cells. Methods: lys-NDs were synthesized earlier through covalent conjugation of lysine amino acid to carboxylated NDs surface generated through re-oxidation in strong oxidizing acids. In this study, dispersions of lys-NDs were prepared in various media, and the degree of sedimentation was monitored for 72 hours. Particle size distributions and zeta potential measurements were performed for a period of 25 days to characterize the physicochemical stability of lys-NDs in the medium. The interaction profile of lys-NDs with fetal bovine serum showed formation of a protein corona, which was evaluated by size and charge distribution measurements. Uptake of lys-NDs in cervical cancer cells was analyzed by scanning transmission X-ray microscopy, flow cytometry, and confocal microscopy. Cellular uptake of diamoplexes (complex of lys-NDs with small interfering RNA was also analyzed using flow cytometry. Results: Aqueous dispersion of lys-NDs showed minimum sedimentation and remained stable over a period of 25 days. Size distributions showed

Colloidal nematostatics

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V.M. Pergamenshchik

2010-01-01

Full Text Available We give a review of the theory of large distance colloidal interaction via the nematic director field. The new area of nematic colloidal systems (or nematic emulsions has been guided by the analogy between the colloidal nematostatics and electrostatics. The elastic charge density representation of the colloidal nematostatics [V.M. Pergamenshchik, V.O. Uzunova, Eur. Phys. J. E, 2007, 23, 161; Phys. Rev. E, 2007, 76, 011707] develops this analogy at the level of charge density and Coulomb interaction. The analogy is shown to lie in common mathematics based on the solutions of Laplace equation. However, the 3d colloidal nematostatics substantially differs from electrostatics both in its mathematical structure and physical implications. The elastic charge is a vector fully determined by the torque exerted upon colloid, the role of Gauss' theorem is played by conservation of the torque components. Elastic multipoles consist of two tensors (dyads. Formulas for the elastic multipoles, the Coulomb-like, dipole-dipole, and quadrupole-quadrupole pair interaction potentials are derived and illustrated by particular examples. Based on the tensorial structure, we list possible types of elastic dipoles and quadrupoles. An elastic dipole is characterized by its isotropic strength, anisotropy, chirality, and its longitudinal component. An elastic quadrupole can be uniaxial and biaxial. Relation between the multipole type and its symmetry is discussed, sketches of some types of multipoles are given. Using the mirror image method of electrostatics as a guiding idea, we develop the mirror image method in nematostatics for arbitrary director tilt at the wall. The method is applied to the charge-wall and dipole-wall interaction.

Antimicrobial Peptide-Driven Colloidal Transformations in Liquid-Crystalline Nanocarriers

DEFF Research Database (Denmark)

Gontsarik, Mark; Buhmann, Matthias T; Yaghmur, Anan

2016-01-01

Designing efficient colloidal systems for the delivery of membrane active antimicrobial peptides requires in-depth understanding of their structural and morphological characteristics. Using dispersions of inverted type bicontinuous cubic phase (cubosomes), we examine the effect of integrating...... structure, inducing colloidal transformations to sponge and lamellar phases and micelles in a concentration-dependent manner. These investigations, together with in vitro evaluation studies using a clinically relevant bacterial strain, established the composition-nanostructure-activity relationship that can...

Colloid formation in groundwater by subsurface aeration: characterisation of the geo-colloids and their counterparts

International Nuclear Information System (INIS)

Wolthoorn, Anke; Temminghoff, Erwin J.M.; Riemsdijk, Willem H. van

2004-01-01

Subsurface aeration is used to oxidise Fe in situ in groundwater to make the water potable. In a groundwater system with pH > 7, subsurface aeration results in a non-mobile Fe precipitate and mobile Fe colloids. Since originally the goal of subsurface aeration is to remove Fe in situ, the formation of non-mobile Fe precipitate is the desired result. In addition to this intended effect, subsurface aeration may also strongly enhance the microbiological removal of NH 4 in the purification station. A hypothesis is that mobile Fe colloids may be the link between subsurface aeration and the positive effect on the microbiological removal of NH 4 . The objective of this study is to characterise the mobile Fe colloids and to derive a synthetic substitute for the naturally formed Fe colloids in order to be able to apply the Fe colloids as a management tool to enhance the removal of NH 4 in the process of producing drinking water from groundwater. At a purification station in The Netherlands natural Fe colloids from an aerated well were sampled. Furthermore, eight synthetic Fe colloids were prepared by oxidising synthetic solutions differing in elemental composition. The colloids were analysed using chemical analysis and electron microscopy (SEM and SEM-EDAX). The Fe colloids sampled in the field contained Fe, Ca, Na, PO 4 and Mn. Also in the synthetic Fe colloids PO 4 , Ca, Na and Mn were the most important elements next to Fe. Phosphate and dissolved organic C strongly influenced the morphology of the synthetic Fe colloids. When both the elemental composition and the morphology of the Fe colloids are taken into account, the synthetic Fe colloids formed in the synthetic solution containing Fe, Mn, PO 4 , SiO 4 and dissolved organic matter best match the Fe colloids from the field

Colloid formation in groundwater by subsurface aeration: characterisation of the geo-colloids and their counterparts

Energy Technology Data Exchange (ETDEWEB)

Wolthoorn, Anke; Temminghoff, Erwin J.M.; Riemsdijk, Willem H. van

2004-09-01

Subsurface aeration is used to oxidise Fe in situ in groundwater to make the water potable. In a groundwater system with pH > 7, subsurface aeration results in a non-mobile Fe precipitate and mobile Fe colloids. Since originally the goal of subsurface aeration is to remove Fe in situ, the formation of non-mobile Fe precipitate is the desired result. In addition to this intended effect, subsurface aeration may also strongly enhance the microbiological removal of NH{sub 4} in the purification station. A hypothesis is that mobile Fe colloids may be the link between subsurface aeration and the positive effect on the microbiological removal of NH{sub 4}. The objective of this study is to characterise the mobile Fe colloids and to derive a synthetic substitute for the naturally formed Fe colloids in order to be able to apply the Fe colloids as a management tool to enhance the removal of NH{sub 4} in the process of producing drinking water from groundwater. At a purification station in The Netherlands natural Fe colloids from an aerated well were sampled. Furthermore, eight synthetic Fe colloids were prepared by oxidising synthetic solutions differing in elemental composition. The colloids were analysed using chemical analysis and electron microscopy (SEM and SEM-EDAX). The Fe colloids sampled in the field contained Fe, Ca, Na, PO{sub 4} and Mn. Also in the synthetic Fe colloids PO{sub 4}, Ca, Na and Mn were the most important elements next to Fe. Phosphate and dissolved organic C strongly influenced the morphology of the synthetic Fe colloids. When both the elemental composition and the morphology of the Fe colloids are taken into account, the synthetic Fe colloids formed in the synthetic solution containing Fe, Mn, PO{sub 4}, SiO{sub 4} and dissolved organic matter best match the Fe colloids from the field.

Gluten: a two-edged sword. Immunopathogenesis of celiac disease

NARCIS (Netherlands)

Koning, de F.; Gilissen, L.J.W.J.; Wijmenga, C.

2005-01-01

Celiac disease (CD) is a small intestinal disorder caused by adaptive and innate immune responses triggered by the gluten proteins present in wheat. In the intestine, gluten is partially degraded and modified, which results in gluten peptides that bind with high affinity to HLA-DQ2 or HLA-DQ8 and

Slow Auger Relaxation in HgTe Colloidal Quantum Dots.

Science.gov (United States)

Melnychuk, Christopher; Guyot-Sionnest, Philippe

2018-05-03

The biexciton lifetimes in HgTe colloidal quantum dots are measured as a function of particle size. Samples produced by two synthetic methods, leading to partially aggregated or well-dispersed particles, exhibit markedly different dynamics. The relaxation characteristics of partially aggregated HgTe inhibit reliable determinations of the Auger lifetime. In well-dispersed HgTe quantum dots, the biexciton lifetime increases approximately linearly with particle volume, confirming trends observed in other systems. The extracted Auger coefficient is three orders of magnitude smaller than that for bulk HgCdTe materials with similar energy gaps. We discuss these findings in the context of understanding Auger relaxation in quantum-confined systems and their relevance to mid-infrared optoelectronic devices based on HgTe colloidal quantum dots.

Divergence of gut permeability and mucosal immune gene expression in two gluten-associated conditions: celiac disease and gluten sensitivity

Directory of Open Access Journals (Sweden)

Esposito Pasquale

2011-03-01

Full Text Available Abstract Background Celiac disease (CD is an autoimmune enteropathy triggered by the ingestion of gluten. Gluten-sensitive individuals (GS cannot tolerate gluten and may develop gastrointestinal symptoms similar to those in CD, but the overall clinical picture is generally less severe and is not accompanied by the concurrence of tissue transglutaminase autoantibodies or autoimmune comorbidities. By studying and comparing mucosal expression of genes associated with intestinal barrier function, as well as innate and adaptive immunity in CD compared with GS, we sought to better understand the similarities and differences between these two gluten-associated disorders. Methods CD, GS and healthy, gluten-tolerant individuals were enrolled in this study. Intestinal permeability was evaluated using a lactulose and mannitol probe, and mucosal biopsy specimens were collected to study the expression of genes involved in barrier function and immunity. Results Unlike CD, GS is not associated with increased intestinal permeability. In fact, this was significantly reduced in GS compared with controls (P = 0.0308, paralleled by significantly increased expression of claudin (CLDN 4 (P = 0.0286. Relative to controls, adaptive immunity markers interleukin (IL-6 (P = 0.0124 and IL-21 (P = 0.0572 were expressed at higher levels in CD but not in GS, while expression of the innate immunity marker Toll-like receptor (TLR 2 was increased in GS but not in CD (P = 0.0295. Finally, expression of the T-regulatory cell marker FOXP3 was significantly reduced in GS relative to controls (P = 0.0325 and CD patients (P = 0.0293. Conclusions This study shows that the two gluten-associated disorders, CD and GS, are different clinical entities, and it contributes to the characterization of GS as a condition associated with prevalent gluten-induced activation of innate, rather than adaptive, immune responses in the absence of detectable changes in mucosal barrier function.

Acid Hydrolysis of Wheat Gluten Induces Formation of New Epitopes but Does Not Enhance Sensitizing Capacity by the Oral Route: A Study in “Gluten Free” Brown Norway Rats

Science.gov (United States)

Kroghsbo, Stine; Andersen, Nanna B.; Rasmussen, Tina F.; Madsen, Charlotte B.

2014-01-01

Background Acid hydrolyzed wheat proteins (HWPs) are used in the food and cosmetic industry as emulsifiers. Cases of severe food allergic reactions caused by HWPs have been reported. Recent data suggest that these reactions are caused by HWPs produced by acid hydrolysis. Objectives To examine the sensitizing capacity of gluten proteins per se when altered by acid or enzymatic hydrolysis relative to unmodified gluten in rats naïve to gluten. Methods High IgE-responder Brown Norway (BN) rats bred on a gluten-free diet were sensitized without the use of adjuvant to three different gluten products (unmodified, acid hydrolyzed and enzymatic hydrolyzed). Rats were sensitized by intraperitoneal (i.p.) immunization three times with 200 µg gluten protein/rat or by oral dosing for 35 days with 0.2, 2 or 20 mg gluten protein/rat/day. Sera were analyzed for specific IgG and IgE and IgG-binding capacity by ELISA. IgE functionality was measured by rat basophilic leukemia (RBL) assay. Results Regardless of the route of dosing, all products had sensitizing capacity. When sensitized i.p., all three gluten products induced a strong IgG1 response in all animals. Acid hydrolyzed gluten induced the highest level of specific IgE but with a low functionality. Orally all three gluten products induced specific IgG1 and IgE but with different dose-response relations. Sensitizing rats i.p. or orally with unmodified or enzymatic hydrolyzed gluten induced specific IgG1 responses with similar binding capacity which was different from that of acid hydrolyzed gluten indicating that acid hydrolysis of gluten proteins induces formation of ‘new’ epitopes. Conclusions In rats not tolerant to gluten acid hydrolysis of gluten enhances the sensitizing capacity by the i.p. but not by the oral route. In addition, acid hydrolysis induces formation of new epitopes. This is in contrast to the enzymatic hydrolyzed gluten having an epitope pattern similar to unmodified gluten. PMID:25207551

Gluten Introduction and the Risk of Coeliac Disease

DEFF Research Database (Denmark)

Szajewska, Hania; Shamir, Raanan; Mearin, Luisa

2016-01-01

-feeding should be promoted for its other well-established health benefits, neither any breast-feeding nor breast-feeding during gluten introduction has been shown to reduce the risk of CD. Gluten may be introduced into the infant's diet anytime between 4 and 12 completed months of age. In children at high risk......BACKGROUND: The European Society for Paediatric Gastroenterology, Hepatology and Nutrition recommended in 2008, based on observational data, to avoid both early (breast-fed. New evidence...... prompted ESPGHAN to revise these recommendations. OBJECTIVE: To provide updated recommendations regarding gluten introduction in infants and the risk of developing coeliac disease (CD) during childhood. SUMMARY: The risk of inducing CD through a gluten-containing diet exclusively applies to persons...

Treatment of celiac disease: from gluten-free diet to novel therapies.

Science.gov (United States)

Francavilla, R; Cristofori, F; Stella, M; Borrelli, G; Naspi, G; Castellaneta, S

2014-10-01

Gluten-free diet (GFD) is the cornerstone treatment for celiac disease (CD). This diet excludes the protein gluten a protein forum in in grains such as wheat, barley, rye and triticale. Gluten causes small intestines inflammation in patients with CD and eating a GFD helps these patients in controlling signs and symptoms and prevent complications. Following a GFD may be frustrating, however, it is important to know that plenty of foods are naturally gluten-free and nowadays is relatively easy to find substitutes for gluten-containing foods. Certain grains, such as oats, are generally safe but can be contaminated with wheat during growing and processing stages of production. For this reason, it is generally recommended avoiding oats unless they are specifically labelled gluten-free. Other products that may contain gluten include food additives, such as malt flavouring, modified food starch and some supplement and/or vitamins that use gluten as a binding agent. Cross-contamination occurs when gluten-free foods come into contact with foods that contain gluten. It can happen during the manufacturing process or if the same equipment is used to make a variety of products. Cross-contamination can also occur at home if foods are prepared on common surfaces or with utensils that have not been cleaned after being used to prepare gluten-containing foods (using a toaster for gluten-free and regular bread). Although safe and effective, the GFD is not ideal: it is expensive, of limited nutritional value, and not readily available in many countries. Consequently, a need exists for novel, non-dietary therapies for celiac disease. Advances in understanding the immunopathogenesis of CD have suggested several types of therapeutic strategies alternative to the GFD. Some of these strategies attempt to decrease the immunogenicity of gluten-containing grains by manipulating the grain itself or by using oral enzymes to break down immunogenic peptides that normally remain intact during

Valence holes observed in nanodiamonds dispersed in water

Science.gov (United States)

Petit, Tristan; Pflüger, Mika; Tolksdorf, Daniel; Xiao, Jie; Aziz, Emad F.

2015-02-01

Colloidal dispersion is essential for most nanodiamond applications, but its influence on nanodiamond electronic properties remains unknown. Here we have probed the electronic structure of oxidized detonation nanodiamonds dispersed in water by using soft X-ray absorption and emission spectroscopies at the carbon and oxygen K edges. Upon dispersion in water, the π* transitions from sp2-hybridized carbon disappear, and holes in the valence band are observed.Colloidal dispersion is essential for most nanodiamond applications, but its influence on nanodiamond electronic properties remains unknown. Here we have probed the electronic structure of oxidized detonation nanodiamonds dispersed in water by using soft X-ray absorption and emission spectroscopies at the carbon and oxygen K edges. Upon dispersion in water, the π* transitions from sp2-hybridized carbon disappear, and holes in the valence band are observed. Electronic supplementary information (ESI) available: Experimental methods, details on XAS/XES normalization and background correction procedures. See DOI: 10.1039/c4nr06639a

Colloid Mobilization in Two Atlantic Coastal Plain Aquifers: Field Studies

Science.gov (United States)

Ryan, Joseph N.; Gschwend, Philip M.

1990-02-01

The geochemical mechanisms leading to the mobilization of colloids in groundwater were investigated in the Pine Barrens of New Jersey and in rural central Delaware by sampling pairs of wells screened in oxic and anoxic groundwaters in the same geologic formations. Samples were carefully taken at very low flow rates (˜100 mL min-1) to avoid suspending immobilized particles. The colloidal matter was characterized by light-scattering photometry, scanning electron microscopy, energy-dispersive X ray analysis, microelectrophoresis, and Fe, Al, Si, and organic carbon analyses. The colloids, composed primarily of clays, were observed at high concentrations (up to 60 mg colloids/L) in the anoxic groundwaters, while the oxic groundwaters exhibited ≤1 mg colloids/L. Colloidal organic carbon was present in all groundwaters; but under anoxic conditions, one-third to one-half of the total organic carbon was associated with the inorganic colloids. The field evidence indicates that anoxic conditions cause the mobilization of soil colloids by dissolving the ferric oxyhydroxide coatings cementing the clay particles to the aquifer solids. The depletion of oxidized iron on the surfaces of immobile particles and the addition of organic carbon coatings on the soil particles and colloids apparently stabilizes the colloidal suspension in the anoxic groundwaters.

The effects of gluten-free diet versus hypocaloric diet among patients with fibromyalgia experiencing gluten sensitivity symptoms: protocol for a pilot, open-label, randomized clinical trial.

Science.gov (United States)

Slim, Mahmoud; Molina-Barea, Rocio; Garcia-Leiva, Juan Miguel; Rodríguez-Lopez, Carmen Maria; Morillas-Arques, Piedad; Rico-Villademoros, Fernando; Calandre, Elena P

2015-01-01

Fibromyalgia is a chronic musculoskeletal pain syndrome characterized by a broad spectrum of manifestations. Patients with fibromyalgia frequently suffer from manifestations similar to those experienced by patients with gluten-related disorders raising the possibility that some patients with fibromyalgia could suffer from underlying gluten sensitivity. This study aims to assess whether avoiding gluten among patients with fibromyalgia and gluten sensitivity is beneficial. Adult patients with fibromyalgia presenting gluten sensitivity symptoms are randomly allocated to receive gluten-free diet or hypocaloric diet for 24 weeks. The primary outcome measure is the mean change in the number of experienced gluten sensitivity symptoms. Secondary outcome measures include the mean changes in the body mass index, Revised Fibromyalgia Impact Questionnaire, Pittsburgh Sleep Quality Index, Brief Pain Inventory, Beck Depression Inventory-II, State-Trait Anxiety Inventory, Short-Form Health Survey and Patient Global Impression Scale of Severity. Other secondary outcome measures include the frequency of potential adverse events and the proportion of responders according to the Patient Global Impression Scale of Improvement. Previous studies assessing dietary interventions in fibromyalgia primarily evaluated their effects on the severity and impact of fibromyalgia symptoms and pain. The current study is the first to evaluate the effects of gluten-free diet on the gluten sensitivity symptoms experienced by patients with fibromyalgia. The results of this study will contribute to a better understanding of the potential role of gluten sensitivity in fibromyalgia. Copyright © 2014 Elsevier Inc. All rights reserved.

Colloid suspension stability and transport through unsaturated porous media

International Nuclear Information System (INIS)

McGraw, M.A.; Kaplan, D.I.

1997-04-01

Contaminant transport is traditionally modeled in a two-phase system: a mobile aqueous phase and an immobile solid phase. Over the last 15 years, there has been an increasing awareness of a third, mobile solid phase. This mobile solid phase, or mobile colloids, are organic or inorganic submicron-sized particles that move with groundwater flow. When colloids are present, the net effect on radionuclide transport is that radionuclides can move faster through the system. It is not known whether mobile colloids exist in the subsurface environment of the Hanford Site. Furthermore, it is not known if mobile colloids would likely exist in a plume emanating from a Low Level Waste (LLW) disposal site. No attempt was made in this study to ascertain whether colloids would form. Instead, experiments and calculations were conducted to evaluate the likelihood that colloids, if formed, would remain in suspension and move through saturated and unsaturated sediments. The objectives of this study were to evaluate three aspects of colloid-facilitated transport of radionuclides as they specifically relate to the LLW Performance Assessment. These objectives were: (1) determine if the chemical conditions likely to exist in the near and far field of the proposed disposal site are prone to induce flocculation (settling of colloids from suspension) or dispersion of naturally occurring Hanford colloids, (2) identify the important mechanisms likely involved in the removal of colloids from a Hanford sediment, and (3) determine if colloids can move through unsaturated porous media

Electroacoustic theory for concentrated colloids with overlapped DLs at arbitrary kappa alpha. I. Application to nanocolloids and nonaqueous colloids.

Science.gov (United States)

Shilov, V N; Borkovskaja, Y B; Dukhin, A S

2004-09-15

Existing theories of electroacoustic phenomena in concentrated colloids neglect the possibility of double layer overlap and are valid mostly for the "thin double layer," when the double layer thickness is much less than the particle size. In this paper we present a new electroacoustic theory which removes this restriction. This would make this new theory applicable to characterizing a variety of aqueous nanocolloids and of nonaqueous dispersions. There are two versions of the theory leading to the analytical solutions. The first version corresponds to strongly overlapped diffuse layers (so-called quasi-homogeneous model). It yields a simple analytical formula for colloid vibration current (CVI), which is valid for arbitrary ultrasound frequency, but for restricted kappa alpha range. This version of the theory, as well the Smoluchowski theory for microelectrophoresis, is independent of particle shape and polydispersity. This makes it very attractive for practical use, with the hope that it might be as useful as classical Smoluchowski theory. In order to determine the kappa alpha range of the quasi-homogeneous model validity we develop the second version that limits ultrasound frequency, but applies no restriction on kappa alpha. The ultrasound frequency should substantially exceed the Maxwell-Wagner relaxation frequency. This limitation makes active conductivity related current negligible compared to the passive dielectric displacement current. It is possible to derive an expression for CVI in the concentrated dispersion as formulae inhering definite integrals with integrands depending on equilibrium potential distribution. This second version allowed us to estimate the ranges of the applicability of the first, quasi-homogeneous version. It turns out that the quasi-homogeneous model works for kappa alpha values up to almost 1. For instance, at volume fraction 30%, the highest kappa alpha limit of the quasi-homogeneous model is 0.65. Therefore, this version of the

Intake and sources of gluten in 20- to 75-year-old Danish adults

DEFF Research Database (Denmark)

Hoppe, Camilla; Gøbel, Rikke Juul; Kristensen, Mette

2017-01-01

PURPOSE: Celiac disease, an immunological response triggered by gluten, affects ~1 % of the Western population. Information concerning gluten intake in the general population is scarce. We determined intake of gluten from wheat, barley, rye and oat in the Danish National Survey of Diet and Physical...... with the amount of cereal used in recipes. Amount of gluten was calculated as amount of cereal protein ×0.80 for wheat and oat, ×0.65 for rye and ×0.50 for barley. Dietary intake was recorded daily during seven consecutive days in pre-coded food diaries with open-answer possibilities. RESULTS: Mean total gluten...... gluten sources tended to be higher in men than in women with the exception of gluten from barley. Total gluten intake decreased with increasing age (P gluten intake from wheat (P gluten from rye (P

Colloidal processing and rapid prototyping of Si{sub 3}N{sub 4}

Energy Technology Data Exchange (ETDEWEB)

Liwu Wang

1998-12-01

Some progresses have been made in the wet shaping of Si{sub 3}N{sub 4} based on a better understanding of the colloidal behavior of suspensions and by improved pressure casting with porous polystyrene (PS) molds. This work illustrated that the combination of proper colloidal processing and rapid prototyping is an effective way to fabricate high-performance ceramics with complex shapes. In colloidal processing the packing density and microstructure of green bodies can be controlled if the interaction between ceramic particles in suspensions and the conditions under which the suspensions are consolidated are understood. Therefore, detailed studies on the surface chemistry of the Si{sub 3}N{sub 4} powder, the dispersing behavior of Si{sub 3}N{sub 4} suspensions, the influence of dispersants and the mechanism during powder consolidation into complex-shaped green bodies are performed. (orig.)

Tuning the morphology, stability and photocatalytic activity of TiO2 nanocrystal colloids by tungsten doping

International Nuclear Information System (INIS)

Xu, Haiping; Liao, Jianhua; Yuan, Shuai; Zhao, Yin; Zhang, Meihong; Wang, Zhuyi; Shi, Liyi

2014-01-01

Graphical abstract: - Highlights: • W 6+ -doped TiO 2 nanocrystal colloids were prepared by hydrothermal methods. • The properties of TiO 2 nanocrystal colloids can be tuned by tungsten doping. • W 6+ -doped TiO 2 nanocrystal colloids show higher stability and dispersity. • W 6+ -doped TiO 2 nanocrystal colloids show higher photocatalytic activity. - Abstract: The effects of tungsten doping on the morphology, stability and photocatalytic activity of TiO 2 nanocrystal colloids were investigated. The nanostructure, chemical state of Ti, W, O, and the properties of tungsten doped TiO 2 samples were investigated carefully by TEM, XRD, XPS, UV–vis, PL and photocatalytic degradation experiments. And the structure–activity relationship was discussed according to the analysis and measurement results. The analysis results reveal that the morphology, zeta potential and photocatalytic activity of TiO 2 nanocrystals can be easily tuned by changing the tungsten doping concentration. The tungsten doped TiO 2 colloid combines the characters of high dispersity and high photocatalytic activity

Colloid and interface chemistry for nanotechnology

CERN Document Server

Kralchevsky, Peter; Ravera, Francesca

2016-01-01

Colloid and interface science dealt with nanoscale objects for nearly a century before the term nanotechnology was coined. An interdisciplinary field, it bridges the macroscopic world and the small world of atoms and molecules. Colloid and Interface Chemistry for Nanotechnology is a collection of manuscripts reflecting the activities of research teams that have been involved in the networking project Colloid and Interface Chemistry for Nanotechnology (2006-2011), Action D43, the European Science Foundation. The project was a part of the intergovernmental framework for Cooperation in Science and Technology (COST), allowing the coordination of nationally funded research across Europe. With contributions by leading experts, this book covers a wide range of topics. Chapters are grouped into three sections: "Nanoparticle Synthesis and Characterization," "New Experimental Tools and Interpretation," and "Nanocolloidal Dispersions and Interfaces." The topics covered belong to six basic research areas: (1) The synthes...

Impact of acid and alkaline pretreatments on the molecular network of wheat gluten and on the mechanical properties of compression-molded glassy wheat gluten bioplastics.

Science.gov (United States)

Jansens, Koen J A; Lagrain, Bert; Brijs, Kristof; Goderis, Bart; Smet, Mario; Delcour, Jan A

2013-10-02

Wheat gluten can be converted into rigid biobased materials by high-temperature compression molding at low moisture contents. During molding, a cross-linked protein network is formed. This study investigated the effect of mixing gluten with acid/alkali in 70% ethanol at ambient temperature for 16 h followed by ethanol removal, freeze-drying, and compression molding at 130 and 150 °C on network formation and on types of cross-links formed. Alkaline pretreatment (0-100 mmol/L sodium hydroxide or 25 mmol/L potassium hydroxide) strongly affected gluten cross-linking, whereas acid pretreatment (0-25 mmol/L sulfuric acid or 25 mmol/L hydrochloric acid) had limited effect on the gluten network. Molded alkaline-treated gluten showed enhanced cross-linking but also degradation when treated with high alkali concentrations, whereas acid treatment reduced gluten cross-linking. β-Elimination of cystine and lanthionine formation occurred more pronouncedly at higher alkali concentrations. In contrast, formation of disulfide and nondisulfide cross-links during molding was hindered in acid-pretreated gluten. Bioplastic strength was higher for alkali than for acid-pretreated samples, whereas the flexural modulus was only slightly affected by either alkaline or acid pretreatment. Apparently, the ratio of disulfide to nondisulfide cross-links did not affect the mechanical properties of rigid gluten materials.

Acid Hydrolysis of Wheat Gluten Induces Formation of New Epitopes but Does Not Enhance Sensitizing Capacity by the Oral Route: A Study in “Gluten Free” Brown Norway Rats

DEFF Research Database (Denmark)

Kroghsbo, Stine; Andersen, Nanna Birch; Rasmussen, Tina Frid

2014-01-01

the sensitizing capacity of gluten proteins per se when altered by acid or enzymatic hydrolysis relative to unmodified gluten in rats naïve to gluten. Methods High IgE-responder Brown Norway (BN) rats bred on a gluten-free diet were sensitized without the use of adjuvant to three different gluten products...... (unmodified, acid hydrolyzed and enzymatic hydrolyzed). Rats were sensitized by intraperitoneal (i.p.) immunization three times with 200 µg gluten protein/rat or by oral dosing for 35 days with 0.2, 2 or 20 mg gluten protein/rat/day. Sera were analyzed for specific IgG and IgE and IgG-binding capacity...... by ELISA. IgE functionality was measured by rat basophilic leukemia (RBL) assay. Results Regardless of the route of dosing, all products had sensitizing capacity. When sensitized i.p., all three gluten products induced a strong IgG1 response in all animals. Acid hydrolyzed gluten induced the highest level...

FEBEX bentonite colloid stability in ground water

Energy Technology Data Exchange (ETDEWEB)

Seher, H.; Schaefer, T.; Geckeis, H. [Inst. fuer Nukleare Entsorgung (INE), Forschungszentrum Karlsruhe, 76021 Karlsruhe (Germany)]. e-mail: holger.seher@ine.fzk .de; Fanghaenel, T. [Ruprecht-Karls-Univ. Heidelberg, Physikalisch-Chemisches In st., D-69120 Heidelberg (Germany)

2007-06-15

Coagulation experiments are accomplished to identify the geochemical conditions for the stability of Febex bentonite colloids in granite ground water. The experiments are carried out by varying pH, ionic strength and type of electrolyte. The dynamic light scattering technique (photon correlation spectroscopy) is used to measure the size evolution of the colloids with time. Agglomeration rates are higher in MgCl{sub 2} and CaCl{sub 2} than in NaCl solution. Relative agglomeration rates follow approximately the Schulze-Hardy rule. Increasing agglomeration rates at pH>8 are observed in experiments with MgCl{sub 2} and CaCl{sub 2} which are, however, caused by coprecipitation phenomena. Bentonite colloid stability fields derived from the colloid agglomeration experiments predict low colloid stabilization in granite ground water taken from Aespoe, Sweden, and relatively high colloid stability in Grimsel ground water (Switzerland)

Harnessing Aptamers to Overcome Challenges in Gluten Detection

Directory of Open Access Journals (Sweden)

Rebeca Miranda-Castro

2016-04-01

Full Text Available Celiac disease is a lifelong autoimmune disorder triggered by foods containing gluten, the storage protein in wheat, rye, and barley. The rapidly escalating number of patients diagnosed with this disease poses a great challenge to both food industry and authorities to guarantee food safety for all. Therefore, intensive efforts are being made to establish minimal disease-eliciting doses of gluten and consequently to improve gluten-free labeling. These efforts depend to a high degree on the availability of methods capable of detecting the protein in food samples at levels as low as possible. Current analytical approaches rely on the use of antibodies as selective recognition elements. With limited sensitivity, these methods exhibit some deficiencies that compromise the accuracy of the obtained results. Aptamers provide an ideal alternative for designing biosensors for fast and selective measurement of gluten in foods. This article highlights the challenges in gluten detection, the current status of the use of aptamers for solving this problem, and what remains to be done to move these systems into commercial applications.

Living Gluten Free

Science.gov (United States)

... Disease" Articles Celiac Disease Changes Everything / What is Celiac Disease? / Symptoms, Diagnosis & Treatment / Four Inches and Seven Pounds… / Learning to Live Well with Celiac Disease / Living Gluten-Free Spring 2015 Issue: Volume 10 ...

Immunological characterization of the gluten fractions and their hydrolysates from wheat, rye and barley.

Science.gov (United States)

Rallabhandi, Prasad; Sharma, Girdhari M; Pereira, Marion; Williams, Kristina M

2015-02-18

Gluten proteins in wheat, rye and barley cause celiac disease, an autoimmune disorder of the small intestine, which affects approximately 1% of the world population. Gluten is comprised of prolamin and glutelin. Since avoidance of dietary gluten is the only option for celiac patients, a sensitive gluten detection and quantitation method is warranted. Most regulatory agencies have set a threshold of 20 ppm gluten in foods labeled gluten-free, based on the currently available ELISA methods. However, these methods may exhibit differences in gluten quantitation from different gluten-containing grains. In this study, prolamin and glutelin fractions were isolated from wheat, rye, barley, oats and corn. Intact and pepsin-trypsin (PT)-digested prolamin and glutelin fractions were used to assess their immunoreactivity and gluten recovery by three sandwich and two competitive ELISA kits. The Western blots revealed varied affinity of ELISA antibodies to gluten-containing grain proteins and no reactivity to oat and corn proteins. ELISA results showed considerable variation in gluten recoveries from both intact and PT-digested gluten fractions among different kits. Prolamin fractions showed higher gluten recovery compared to their respective glutelin fractions. Among prolamins, barley exhibited higher recovery compared to wheat and rye with most of the ELISA kits used. Hydrolysis resulted in reduced gluten recovery of most gluten fractions. These results suggest that the suitability of ELISA for accurate gluten quantitation is dependent upon various factors, such as grain source, antibody specificity, gluten proteins and the level of their hydrolysis in foods.

Multipole expansion of the retarded interatomic dispersion energy: derivation from quantum electrodynamics

NARCIS (Netherlands)

Michels, M.A.J.; Suttorp, L.G.

1972-01-01

The multipole expansion of the retarded dispersion energy of two atoms in nondegenerate ground states is derived. The result shows that multipoles of different order may give rise to dispersion energies varying in the same way for large interatomic separations.

Is gluten a cause of gastrointestinal symptoms in people without celiac disease?

Science.gov (United States)

Biesiekierski, Jessica R; Muir, Jane G; Gibson, Peter R

2013-12-01

The avoidance of wheat- and gluten-containing products is a worldwide phenomenon. While celiac disease is a well-established entity, the evidence base for gluten as a trigger of symptoms in patients without celiac disease (so-called 'non-celiac gluten sensitivity' or NCGS) is limited. The problems lie in the complexity of wheat and the ability of its carbohydrate as well as protein components to trigger gastrointestinal symptoms, the potentially false assumption that response to a gluten-free diet equates to an effect of gluten withdrawal, and diagnostic criteria for coeliac disease. Recent randomized controlled re-challenge trials have suggested that gluten may worsen gastrointestinal symptoms, but failed to confirm patients with self-perceived NCGS have specific gluten sensitivity. Furthermore, mechanisms by which gluten triggers symptoms have yet to be identified. This review discusses the most recent scientific evidence and our current understanding of NCGS.

On adiabatic pair potentials of highly charged colloid particles

Science.gov (United States)

Sogami, Ikuo S.

2018-03-01

Generalizing the Debye-Hückel formalism, we develop a new mean field theory for adiabatic pair potentials of highly charged particles in colloid dispersions. The unoccupied volume and the osmotic pressure are the key concepts to describe the chemical and thermodynamical equilibrium of the gas of small ions in the outside region of all of the colloid particles. To define the proper thermodynamic quantities, it is postulated to take an ensemble averaging with respect to the particle configurations in the integrals for their densities consisting of the electric potential satisfying a set of equations that are derived by linearizing the Poisson-Boltzmann equation. With the Fourier integral representation of the electric potential, we calculate first the internal electric energy of the system from which the Helmholtz free energy is obtained through the Legendre transformation. Then, the Gibbs free energy is calculated using both ways of the Legendre transformation with respect to the unoccupied volume and the summation of chemical potentials. The thermodynamic functions provide three types of pair potentials, all of which are inversely proportional to the fraction of the unoccupied volume. At the limit when the fraction factor reduces to unity, the Helmholtz pair potential turns exactly into the well known Derjaguin-Landau-Verwey-Overbeek repulsive potential. The Gibbs pair potential possessing a medium-range strong repulsive part and a long-range weak attractive tail can explain the Schulze-Hardy rule for coagulation in combination with the van der Waals-London potential and describes a rich variety of phenomena of phase transitions observed in the dilute dispersions of highly charged particles.

Whole grain gluten-free pastas and flatbreads

Science.gov (United States)

Whole grain gluten-free products were formulated and evaluated for acceptance by volunteer tasters. The tastes judged acceptance of whole grain, gluten-free, egg-free pastas for corn 83%, sorghum 79%, brown rice 77% and millet 50%. The acceptance for similar high protein pasta was corn-garbanzo 70...

Fundamental Study on the Impact of Gluten-Free Starches on the Quality of Gluten-Free Model Breads

Directory of Open Access Journals (Sweden)

Stefan W. Horstmann

2016-04-01

Full Text Available Starch is widely used as an ingredient and significantly contributes to texture, appearance, and overall acceptability of cereal based foods, playing an important role due to its ability to form a matrix, entrapping air bubbles. A detailed characterisation of five gluten-free starches (corn, wheat, rice, tapioca, potato was performed in this study. In addition, the influence of these starches, with different compositional and morphological properties, was evaluated on a simple gluten-free model bread system. The morphological characterisation, evaluated using scanning electron microscopy, revealed some similarities among the starches, which could be linked to the baking performance of the breads. Moreover, the lipid content, though representing one of the minor components in starch, was found to have an influence on pasting, bread making, and staling. Quality differences in cereal root and tuber starch based breads were observed. However, under the baking conditions used, gluten-free rendered wheat starch performed best, followed by potato starch, in terms of loaf volume and cell structure. Tapioca starch and rice starch based breads were not further analysed, due to an inferior baking performance. This is the first study to evaluate gluten-free starch on a simple model bread system.

Wetting Behavior in Colloid-Polymer Mixtures at Different Substrates.

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Wijting, Willem K; Besseling, Nicolaas A M; Cohen Stuart, Martien A

2003-09-25

We present experimental observations on wetting phenomena in depletion interaction driven, phase separated colloidal dispersions. The contact angle of the colloidal liquid-gas interface at a solid substrate was determined for a series of compositions. Upon approach to the critical point, a transition occurs from partial to complete wetting. The interaction with the substrate was manipulated by modifying the substrate with a polymer. In that case, a transition from partial to complete drying is observed upon approach to the critical point.

Long-term aging behaviors in a model soft colloidal system.

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Li, Qi; Peng, Xiaoguang; McKenna, Gregory B

2017-02-15

Colloidal and molecular systems share similar behaviors near to the glass transition volume fraction or temperature. Here, aging behaviors after volume fraction up-jump (induced by performing temperature down-jumps) conditions for a PS-PNIPAM/AA soft colloidal system were investigated using light scattering (diffusing wave spectroscopy, DWS). Both aging responses and equilibrium dynamics were investigated. For the aging responses, long-term experiments (100 000 s) were performed, and both equilibrium and non-equilibrium behaviors of the system were obtained. In the equilibrium state, as effective volume fraction increases (or temperature decreases), the colloidal dispersion displays a transition from the liquid to a glassy state. The equilibrium α-relaxation dynamics strongly depend on both the effective volume fraction and the initial mass concentration for the studied colloidal systems. Compared with prior results from our lab [X. Di, X. Peng and G. B. McKenna, J. Chem. Phys., 2014, 140, 054903], the effective volume fractions investigated spanned a wider range, to deeper into the glassy domain. The results show that the α-relaxation time τ α of the samples aged into equilibrium deviate from the classical Vogel-Fulcher-Tammann (VFT)-type expectations and the super-Arrhenius signature disappears above the glass transition volume fraction. The non-equilibrium aging response shows that the time for the structural evolution into equilibrium and the α-relaxation time are decoupled. The DWS investigation of the aging behavior after different volume fraction jumps reveals a different non-equilibrium or aging behavior for the considered colloidal systems compared with either molecular glasses or the macroscopic rheology of a similar colloidal dispersions.

Uranium facilitated transport by water-dispersible colloids in field and soil columns

Energy Technology Data Exchange (ETDEWEB)

Crancon, P., E-mail: pierre.crancon@cea.fr [CEA, DAM, DIF, F-91297 Arpajon (France); Pili, E. [CEA, DAM, DIF, F-91297 Arpajon (France); Charlet, L. [Laboratoire de Geophysique Interne et Tectonophysique (LGIT-OSUG), University of Grenoble-I, UMR5559-CNRS-UJF, BP53, 38041 Grenoble cedex 9 (France)

2010-04-01

The transport of uranium through a sandy podzolic soil has been investigated in the field and in column experiments. Field monitoring, numerous years after surface contamination by depleted uranium deposits, revealed a 20 cm deep uranium migration in soil. Uranium retention in soil is controlled by the < 50 {mu}m mixed humic and clayey coatings in the first 40 cm i.e. in the E horizon. Column experiments of uranium transport under various conditions were run using isotopic spiking. After 100 pore volumes elution, 60% of the total input uranium is retained in the first 2 cm of the column. Retardation factor of uranium on E horizon material ranges from 1300 (column) to 3000 (batch). In parallel to this slow uranium migration, we experimentally observed a fast elution related to humic colloids of about 1-5% of the total-uranium input, transferred at the mean porewater velocity through the soil column. In order to understand the effect of rain events, ionic strength of the input solution was sharply changed. Humic colloids are retarded when ionic strength increases, while a major mobilization of humic colloids and colloid-borne uranium occurs as ionic strength decreases. Isotopic spiking shows that both {sup 238}U initially present in the soil column and {sup 233}U brought by input solution are desorbed. The mobilization process observed experimentally after a drop of ionic strength may account for a rapid uranium migration in the field after a rainfall event, and for the significant uranium concentrations found in deep soil horizons and in groundwater, 1 km downstream from the pollution source.

Gluten detection in foods available in the United States - a market survey.

Science.gov (United States)

Sharma, Girdhari M; Pereira, Marion; Williams, Kristina M

2015-02-15

Many gluten-free (GF) food choices are now available in supermarkets. However, the unintentional presence of gluten in these foods poses a serious health risk to wheat-allergic and celiac patients. Different GF labelled foods (275) and non-GF labelled foods, without wheat/rye/barley on the ingredient label (186), were analysed for gluten content by two different enzyme linked immunosorbent assay (ELISA) kits. Considering the gluten threshold of 20ppm, GF labelled foods had 98.9% GF labelling compliance with 1.1% (3 out of 275) of foods being mislabelled/misbranded. Among the non-GF labelled foods, 19.4% (36 out of 186) of foods had >20ppm of gluten, as measured by at least one ELISA kit, of which 19 foods had >100ppm of gluten. The presence of oats in non-GF labelled foods was strongly correlated with a positive ELISA result. Gluten was also found in a significant number of foods with gluten/wheat-related advisory warnings. Published by Elsevier Ltd.

Prevalence of Self-Reported Gluten Sensitivity and Adherence to a Gluten-Free Diet in Argentinian Adult Population

Science.gov (United States)

Cabrera-Chávez, Francisco; Dezar, Gimena V. A.; Islas-Zamorano, Anna P.; Espinoza-Alderete, Jesús G.; Vergara-Jiménez, Marcela J.; Magaña-Ordorica, Dalia; Ontiveros, Noé

2017-01-01

Background: Previous studies suggest that the prevalence of wheat/gluten sensitivity and adherence to a gluten-free diet (GFD) are high in Latin population despite a poor diagnosis of celiac disease. However, these prevalence rates still remain unknown in most Latin American countries. Methods: A cross-sectional survey study was conducted in Santa Fe, Argentina. Results: The estimated self-reported prevalence rates were (95% Confidence Interval [CI]): self-reported gluten sensitivity (SR-GS) 7.61% (6.2–9.2), SR-GS currently following a GFD 1.82% (1.2–2.7), celiac disease 0.58% (0.3–1.2), wheat allergy 0.33% (0.12–0.84), self-reported non-celiac gluten sensitivity (SR-NCGS) 6.28% (5.1–7.8), SR-NCGS currently following a GFD 0.91% (0.5–1.6), and adherence to a GFD 6.37% (5.1–7.9). SR-GS was more common in women (6.0%; p < 0.001) and associated with irritable bowel syndrome (p < 0.001). Among the GFD followers, 71.4% were doing it for reasons other than health-related benefits and 50.6% without medical/dietitian advice. In the non-SR-GS group, the main motivations for following a GFD were weight control and the perception that a GFD is healthier. Conclusion: In Argentina, gluten sensitivity is commonly reported and it seems that physicians/gastroenterologists are aware of celiac disease diagnosis. Trustable information about the benefits and potential consequences of following a GFD should be given to the general population. PMID:28117706

Prevalence of Self-Reported Gluten Sensitivity and Adherence to a Gluten-Free Diet in Argentinian Adult Population

Directory of Open Access Journals (Sweden)

Francisco Cabrera-Chávez

2017-01-01

Full Text Available Background: Previous studies suggest that the prevalence of wheat/gluten sensitivity and adherence to a gluten-free diet (GFD are high in Latin population despite a poor diagnosis of celiac disease. However, these prevalence rates still remain unknown in most Latin American countries. Methods: A cross-sectional survey study was conducted in Santa Fe, Argentina. Results: The estimated self-reported prevalence rates were (95% Confidence Interval [CI]: self-reported gluten sensitivity (SR-GS 7.61% (6.2–9.2, SR-GS currently following a GFD 1.82% (1.2–2.7, celiac disease 0.58% (0.3–1.2, wheat allergy 0.33% (0.12–0.84, self-reported non-celiac gluten sensitivity (SR-NCGS 6.28% (5.1–7.8, SR-NCGS currently following a GFD 0.91% (0.5–1.6, and adherence to a GFD 6.37% (5.1–7.9. SR-GS was more common in women (6.0%; p < 0.001 and associated with irritable bowel syndrome (p < 0.001. Among the GFD followers, 71.4% were doing it for reasons other than health-related benefits and 50.6% without medical/dietitian advice. In the non-SR-GS group, the main motivations for following a GFD were weight control and the perception that a GFD is healthier. Conclusion: In Argentina, gluten sensitivity is commonly reported and it seems that physicians/gastroenterologists are aware of celiac disease diagnosis. Trustable information about the benefits and potential consequences of following a GFD should be given to the general population.

Whole grain gluten-free vegetable spicy snacks

Science.gov (United States)

Four kinds of spicy snacks (gluten-free, whole grains with fresh vegetables, low in fat, sugar and salt) were evaluated. Acceptance of spicy snacks tested were Carrot-Garlic 77%, Broccoli-Garlic 68%, Spinach-Garlic 61% and Red Onion 53%. This is the first report of spicy gluten-free, 50% vegetable...

Gluten-free diet is for some a necessity, for others a lifestyle

DEFF Research Database (Denmark)

Jønsson, Iben Møller; Møller, Gitte Leth; Pærregaard, Anders

2017-01-01

This review provides a brief overview of the gluten-related conditions coeliac disease (CD), wheat allergy (WA), and non-coeliac gluten sensitivity (NCGS). NCGS is a new entity which includes individuals who report symptoms when exposed to gluten and benefit from gluten-free diet, but do not have...

Effect of water unextractable solids on gluten formation and properties: Mechanistic considerations

NARCIS (Netherlands)

Wang, M.; Hamer, R.J.; Vliet, T. van; Gruppen, H.; Marseille, H.; Weegels, P.L.

2003-01-01

A miniaturised set-up for gluten-starch separation was used to systematically study the effect of water unextractable solids (WUS) on the formation and properties of gluten. The results showed that WUS not only have a negative effect on gluten yield, but also affect gluten and glutenin macropolymer

Structure of Colloidal Flocs in relation to the Dynamic Properties of Unstable Suspension

Directory of Open Access Journals (Sweden)

Yasuhisa Adachi

2012-01-01

Full Text Available Dynamic behaviors of unstable colloidal dispersions are reviewed in terms of floc formation. Geometrical structure of flocs in terms of chemical conditions and formation mechanics is a key to predict macroscopic transportation properties. The rate of sedimentation and rheological properties can be described with the help of fractal dimension (D that is the function of the number of contacts between clusters (Nc. It is also well known that the application of water soluble polymers and polyelectrolytes, which are usually used as a conditioner or flocculants in colloidal dispersions, critically affects the process of flocculation. The resulted floc structure is also influenced by the application of polymer. In order to reveal the roles of the polymers, the elementary rate process of polymer reaching to colloidal interface and subsequent reconformation process into more stable adsorption state are needed to be analyzed. The properties of permeable flocs and adsorbed polymer (polyelectrolyte layers formed on the colloidal surfaces remain to be worked out in relation to inhomogeneous porous structure and electrokinetics in the future.

Non-Celiac Gluten Sensitivity and Autoimmunity. A Case Report.

Directory of Open Access Journals (Sweden)

Carlos Isasi

2014-12-01

Full Text Available Introduction, objective: To present a case report in which the finding of non-coeliac gluten sensitivity was decisive for the treatment of a complex autoimmune disease. Materials and methods: A 43-year-old woman with polyarthritis, psoriatic features, anti-SSA/Ro and anti-cyclic citrullinated peptide antibodies, with refractory course, was evaluated for gluten sensitivity despite negative serology for coeliac disease. Results: The patient carried the HLA DQ2 haplotype and duodenal biopsy showed lymphocytic enteritis. A gluten-free diet resolved the clinical picture and permitted tapering of immunosuppressive therapy. Conclusion: Non-coeliac gluten sensitivity can be associated with autoimmunity despite the absence of the specific autoantibodies of coeliac disease.

Gluten-free and casein-free diets in the therapy of autism.

Science.gov (United States)

Lange, Klaus W; Hauser, Joachim; Reissmann, Andreas

2015-11-01

The purpose of this study is to discuss the role of gluten-free and casein-free diets in the treatment of autism. In a recent UK survey, more than 80% of parents of children with autism spectrum disorder reported some kind of dietary intervention for their child (gluten-free and casein-free diet in 29%). When asked about the effects of the gluten-free and casein-free diet, 20-29% of the parents reported significant improvements on the autism spectrum disorder core dimensions. The findings of this study suggest additional effects of a gluten-free and casein-free diet on comorbid problems of autism such as gastrointestinal symptoms, concentration, and attention. The findings of another recent investigation suggested that age and certain urine compounds may predict the response of autism symptoms to a gluten-free and casein-free diet. Although these results need to be replicated, they highlight the importance of patient subgroup analysis. Intervention trials evaluating the effects of a gluten-free and casein-free diet on autistic symptoms have so far been contradictory and inconclusive. Most investigations assessing the efficacy of a gluten-free and casein-free diet in the treatment of autism are seriously flawed. The evidence to support the therapeutic value of this diet is limited and weak. A gluten-free and casein-free diet should only be administered if an allergy or intolerance to nutritional gluten or casein is diagnosed.

A randomised, double-blind, cross-over trial to evaluate bread, in which gluten has been pre-digested by prolyl endoprotease treatment, in subjects self-reporting benefits of adopting a gluten-free or low-gluten diet.

Science.gov (United States)

Rees, Dinka; Holtrop, Grietje; Chope, Gemma; Moar, Kim M; Cruickshank, Morven; Hoggard, Nigel

2018-03-01

The aim of the present study was to determine if the enzyme Aspergillus niger prolyl endoprotease (ANPEP), which degrades the immunogenic proline-rich residues in gluten peptides, can be used in the development of new wheat products, suitable for gluten-sensitive (GS) individuals. We have carried out a double-blind, randomised, cross-over trial with two groups of adults; subjects, self-reporting benefits of adopting a gluten-free or low-gluten diet (GS, n 16) and a control non-GS group (n 12). For the trial, volunteers consumed four wheat breads: normal bread, bread treated with 0·8 or 1 % ANPEP and low-protein bread made from biscuit flour. Compared with controls, GS subjects had a favourable cardiovascular lipid profile - lower LDL (4·0 (sem 0·3) v. 2·8 (sem 0·2) mmol/l; P=0·008) and LDL:HDL ratio (3·2 (sem 0·4) v. 1·8 (sem 0·2); P=0·005) and modified haematological profile. The majority of the GS subjects followed a low-gluten lifestyle, which helps to reduce the gastrointestinal (GI) symptoms severity. The low-gluten lifestyle does not have any effect on the quality of life, fatigue or mental state of this population. Consumption of normal wheat bread increased GI symptoms in GS subjects compared with their habitual diet. ANPEP lowered the immunogenic gluten in the treated bread by approximately 40 %. However, when compared with the control bread for inducing GI symptoms, no treatment effects were apparent. ANPEP can be applied in the production of bread with taste, texture and appearance comparable with standard bread.

Health Benefits and Adverse Effects of a Gluten-Free Diet in Non-Celiac Disease Patients.

Science.gov (United States)

Niland, Benjamin; Cash, Brooks D

2018-02-01

Gluten-related diseases such as celiac disease and gluten ataxia are rare conditions, affecting less than 1% of the population in the United States. Despite the rarity of these diseases, there have been significant increases in the adoption of a gluten-free lifestyle and the consumption of gluten-free foods in the United States over the last 3 decades. More than $15.5 billion were spent on retail sales of gluten-free foods in 2016. The gluten-free diet is driven by multiple factors, including social and traditional media coverage, aggressive consumer-directed marketing by manufacturers and retail outlets, and reports in the medical literature and mainstream press of the clinical benefits of gluten avoidance. Individuals may restrict gluten from their diets for a variety of reasons, such as improvement of gastrointestinal and nongastrointestinal symptoms, as well as a perception that gluten is potentially harmful and, thus, restriction represents a healthy lifestyle. Emerging evidence shows that gluten avoidance may be beneficial for some patients with gastrointestinal symptoms, such as those commonly encountered with irritable bowel syndrome. However, high-quality evidence supporting gluten avoidance for physical symptoms or diseases other than those specifically known to be caused by immune-mediated responses to gluten is neither robust nor convincing. In fact, gluten avoidance may be associated with adverse effects in patients without proven gluten-related diseases. This article provides insight regarding gluten avoidance patterns and effects on patients without gluten-related diseases, and highlights concerns surrounding gluten avoidance in the absence of a gluten-mediated immunologic disease.

[Non-celiac gluten sensitivity: a critical review of current evidence].

Science.gov (United States)

Molina-Infante, Javier; Santolaria, Santos; Montoro, Miguel; Esteve, María; Fernández-Bañares, Fernando

2014-01-01

Non-celiac gluten sensitivity (NCGS) is an emerging disorder characterized by intestinal and extra-intestinal symptoms related to the ingestion of gluten-containing food in non-celiac patients. Its prevalence has been estimated to be six to ten-times higher than that of celiac disease (CD). A gluten-free diet is the most widely recommended therapy, but the causative agent remains unknown and there are no consensus diagnostic criteria. Recent studies on NCGS have included patients with possibly overlooked minor CD and diarrhea-predominant irritable bowel syndrome without self-reported gluten intolerance, but showing a response to a gluten-free diet. Furthermore, FODMAPs (Fermentable Oligosaccharides, Disaccharides, Monosaccharides And Polyols) have recently been postulated as the culprit component for NCGS in wheat, instead of gluten. This review updates evidence on the pathophysiology of NCGS and the efficacy of different dietary interventions in its treatment, stressing the need for proper screening for CD before a diagnosis of NCGS is made. Copyright © 2013 Elsevier España, S.L. and AEEH y AEG. All rights reserved.

Uranium facilitated transport by water-dispersible colloids in field and soil columns

Energy Technology Data Exchange (ETDEWEB)

Crancon, P.; Pili, E. [CEA Bruyeres-le-Chatel, DIF, 91 (France); Charlet, L. [Univ Grenoble 1, Lab Geophys Interne and Tectonophys LGIT OSUG, CNRS, UJF, UMR5559, F-38041 Grenoble 9 (France)

2010-07-01

The transport of uranium through a sandy podsolic soil has been investigated in the field and in column experiments. Field monitoring, numerous years after surface contamination by depleted uranium deposits, revealed a 20 cm deep uranium migration in soil. Uranium retention in soil is controlled by the {<=} 50 {mu}m mixed humic and clayey coatings in the first 40 cm i.e. in the E horizon. Column experiments of uranium transport under various conditions were run using isotopic spiking. After 100 pore volumes elution, 60% of the total input uranium is retained in the first 2 cm of the column. Retardation factor of uranium on E horizon material ranges from 1300 (column) to 3000 (batch). In parallel to this slow uranium migration, we experimentally observed a fast elution related to humic colloids of about 1-5% of the total-uranium input, transferred at the mean pore-water velocity through the soil column. In order to understand the effect of rain events, ionic strength of the input solution was sharply changed. Humic colloids are retarded when ionic strength increases, while a major mobilization of humic colloids and colloid-borne uranium occurs as ionic strength decreases. Isotopic spiking shows that both {sup 238}U initially present in the soil column and {sup 233}U brought by input solution are desorbed. The mobilization process observed experimentally after a drop of ionic strength may account for a rapid uranium migration in the field after a rainfall event, and for the significant uranium concentrations found in deep soil horizons and in groundwater, 1 km downstream from the pollution source. (authors)

Lysine-functionalized nanodiamonds as gene carriers: development of stable colloidal dispersion for in vitro cellular uptake studies and siRNA delivery application

Science.gov (United States)

Alwani, Saniya; Kaur, Randeep; Michel, Deborah; Chitanda, Jackson M; Verrall, Ronald E; Karunakaran, Chithra; Badea, Ildiko

2016-01-01

Purpose Nanodiamonds (NDs) are emerging as an attractive tool for gene therapeutics. To reach their full potential for biological application, NDs should maintain their colloidal stability in biological milieu. This study describes the behavior of lysine-functionalized ND (lys-ND) in various dispersion media, with an aim to limit aggregation and improve the colloidal stability of ND-gene complexes called diamoplexes. Furthermore, cellular and macromolecular interactions of lys-NDs are also analyzed in vitro to establish the understanding of ND-mediated gene transfer in cells. Methods lys-NDs were synthesized earlier through covalent conjugation of lysine amino acid to carboxylated NDs surface generated through re-oxidation in strong oxidizing acids. In this study, dispersions of lys-NDs were prepared in various media, and the degree of sedimentation was monitored for 72 hours. Particle size distributions and zeta potential measurements were performed for a period of 25 days to characterize the physicochemical stability of lys-NDs in the medium. The interaction profile of lys-NDs with fetal bovine serum showed formation of a protein corona, which was evaluated by size and charge distribution measurements. Uptake of lys-NDs in cervical cancer cells was analyzed by scanning transmission X-ray microscopy, flow cytometry, and confocal microscopy. Cellular uptake of diamoplexes (complex of lys-NDs with small interfering RNA) was also analyzed using flow cytometry. Results Aqueous dispersion of lys-NDs showed minimum sedimentation and remained stable over a period of 25 days. Size distributions showed good stability, remaining under 100 nm throughout the testing period. A positive zeta potential of >+20 mV indicated a preservation of surface charges. Size distribution and zeta potential changed for lys-NDs after incubation with blood serum, suggesting an interaction with biomolecules, mainly proteins, and a possible formation of a protein corona. Cellular internalization

Lysine-functionalized nanodiamonds as gene carriers: development of stable colloidal dispersion for in vitro cellular uptake studies and siRNA delivery application.

Science.gov (United States)

Alwani, Saniya; Kaur, Randeep; Michel, Deborah; Chitanda, Jackson M; Verrall, Ronald E; Karunakaran, Chithra; Badea, Ildiko

2016-01-01

Nanodiamonds (NDs) are emerging as an attractive tool for gene therapeutics. To reach their full potential for biological application, NDs should maintain their colloidal stability in biological milieu. This study describes the behavior of lysine-functionalized ND (lys-ND) in various dispersion media, with an aim to limit aggregation and improve the colloidal stability of ND-gene complexes called diamoplexes. Furthermore, cellular and macromolecular interactions of lys-NDs are also analyzed in vitro to establish the understanding of ND-mediated gene transfer in cells. lys-NDs were synthesized earlier through covalent conjugation of lysine amino acid to carboxylated NDs surface generated through re-oxidation in strong oxidizing acids. In this study, dispersions of lys-NDs were prepared in various media, and the degree of sedimentation was monitored for 72 hours. Particle size distributions and zeta potential measurements were performed for a period of 25 days to characterize the physicochemical stability of lys-NDs in the medium. The interaction profile of lys-NDs with fetal bovine serum showed formation of a protein corona, which was evaluated by size and charge distribution measurements. Uptake of lys-NDs in cervical cancer cells was analyzed by scanning transmission X-ray microscopy, flow cytometry, and confocal microscopy. Cellular uptake of diamoplexes (complex of lys-NDs with small interfering RNA) was also analyzed using flow cytometry. Aqueous dispersion of lys-NDs showed minimum sedimentation and remained stable over a period of 25 days. Size distributions showed good stability, remaining under 100 nm throughout the testing period. A positive zeta potential of >+20 mV indicated a preservation of surface charges. Size distribution and zeta potential changed for lys-NDs after incubation with blood serum, suggesting an interaction with biomolecules, mainly proteins, and a possible formation of a protein corona. Cellular internalization of lys-NDs was confirmed

The competing effects of microbially derived polymeric and low molecular-weight substances on the dispersibility of CeO2 nanoparticles

Energy Technology Data Exchange (ETDEWEB)

Nakano, Yuriko; Ochiai, Asumi; Kawamoto, Keisuke; Takeda, Ayaka; Ichiyoshi, Kenta; Ohnuki, Toshihiko; Hochella, Michael F.; Utsunomiya, Satoshi

2018-02-26

To understand the competing effects of the components in extracellular substances (ES), polymeric substances (PS) and low-molecular-weight small substances (SS) <1 kDa derived from microorganisms, on the colloidal stability of cerium dioxide nanoparticles (CeNPs), we investigated their adsorption to sparingly soluble CeNPs at room temperature at pH 6.0. The ES was extracted from the fungus S. cerevisiae. The polypeptides and phosphates in all components preferentially adsorbed onto the CeNPs. The zeta potentials of ES + CeNPs, PS + CeNPs, and SS + CeNPs overlapped on the plot of PS itself, indicating the surface charge of the polymeric substances controls the zeta potentials. The sizes of the CeNP aggregates, 100–1300 nm, were constrained by the zeta potentials. The steric barrier derived from the polymers, even in SS, enhanced the CeNP dispersibility at pH 1.5–10. Consequently, the PS and SS had similar effects on modifying the CeNP surfaces. The adsorption of ES, which contains PS + SS, can suppress the aggregation of CeNPs over a wider pH range than that for PS only. The present study addresses the non-negligible effects of small-sized molecules derived from microbial activity on the migration of CeNP in aquatic environments, especially where bacterial consortia prevail.

Gluten exacerbates IgA nephropathy in humanized mice through gliadin-CD89 interaction.

Science.gov (United States)

Papista, Christina; Lechner, Sebastian; Ben Mkaddem, Sanae; LeStang, Marie-Bénédicte; Abbad, Lilia; Bex-Coudrat, Julie; Pillebout, Evangéline; Chemouny, Jonathan M; Jablonski, Mathieu; Flamant, Martin; Daugas, Eric; Vrtovsnik, François; Yiangou, Minas; Berthelot, Laureline; Monteiro, Renato C

2015-08-01

IgA1 complexes containing deglycosylated IgA1, IgG autoantibodies, and a soluble form of the IgA receptor (sCD89), are hallmarks of IgA nephropathy (IgAN). Food antigens, notably gluten, are associated with increased mucosal response and IgAN onset, but their implication in the pathology remains unknown. Here, an IgAN mouse model expressing human IgA1 and CD89 was used to examine the role of gluten in IgAN. Mice were given a gluten-free diet for three generations to produce gluten sensitivity, and then challenged for 30 days with a gluten diet. A gluten-free diet resulted in a decrease of mesangial IgA1 deposits, transferrin 1 receptor, and transglutaminase 2 expression, as well as hematuria. Mice on a gluten-free diet lacked IgA1-sCD89 complexes in serum and kidney eluates. Disease severity depended on gluten and CD89, as shown by reappearance of IgAN features in mice on a gluten diet and by direct binding of the gluten-subcomponent gliadin to sCD89. A gluten diet exacerbated intestinal IgA1 secretion, inflammation, and villous atrophy, and increased serum IgA1 anti-gliadin antibodies, which correlated with proteinuria in mice and patients. Moreover, early treatment of humanized mice with a gluten-free diet prevented mesangial IgA1 deposits and hematuria. Thus, gliadin-CD89 interaction may aggravate IgAN development through induction of IgA1-sCD89 complex formation and a mucosal immune response. Hence, early-stage treatment with a gluten-free diet could be beneficial to prevent disease.

Skepticism Regarding Vaccine and Gluten-Free Food Safety Among Patients with Celiac Disease and Non-celiac Gluten Sensitivity.

Science.gov (United States)

Rabinowitz, Loren G; Zylberberg, Haley M; Levinovitz, Alan; Stockwell, Melissa S; Green, Peter H R; Lebwohl, Benjamin

2018-05-01

There has been a marked increase in the adoption of the gluten-free (GF) diet. To query individuals with celiac disease (CD) and non-celiac gluten sensitivity (NCGS) on their beliefs toward the health effects of gluten, and safety of vaccines and GF food products. We distributed a Web-based survey to individuals with CD and NCGS on a CD center e-mail list. We used univariate and multivariate analysis to compare responses of respondents with CD and NCGS. The overall response rate was 27% (NCGS n = 217, CD n = 1291). Subjects with NCGS were more likely than those with CD to disagree with the statement that "vaccines are safe for people with celiac disease" (NCGS 41.3% vs. CD 26.4% (p diet improves energy and concentration (aOR 2.52; 95% CI 1.86-3.43). Subjects with NCGS were more likely than those with CD to have doubts about vaccine safety and believe in the value of non-GMO and organic foods. Our findings suggest that the lack of reliable information on gluten and its content in food and medications may reinforce beliefs that result in a detriment to public health.

Sustainable steric stabilization of colloidal titania nanoparticles

Energy Technology Data Exchange (ETDEWEB)

Elbasuney, Sherif, E-mail: sherif_basuney2000@yahoo.com

2017-07-01

Graphical abstract: Controlled surface properties of titania nanoparticles via surface modification, flocculation from aqueous phase (a), stabilization in aqueous phase (b), extraction to organic phase (c). - Highlights: • Complete change in surface properties of titania nanoparticles from hydrophilic to hydrophobic. • Harvesting the formulated nanoparticles from the aqueous phase to the organic phase. • Exclusive surface modification in the reactor during nanoparticle synthesis. • Sustainable stabilization of titania nanoparticles in aqueous media with polar polymeric dispersant. - Abstract: A route to produce a stable colloidal suspension is essential if mono-dispersed particles are to be successfully synthesized, isolated, and used in subsequent nanocomposite manufacture. Dispersing nanoparticles in fluids was found to be an important approach for avoiding poor dispersion characteristics. However, there is still a great tendency for colloidal nanoparticles to flocculate over time. Steric stabilization can prevent coagulation by introducing a thick adsorbed organic layer which constitutes a significant steric barrier that can prevent the particle surfaces from coming into direct contact. One of the main features of hydrothermal synthesis technique is that it offers novel approaches for sustainable nanoparticle surface modification. This manuscript reports on the sustainable steric stabilization of titanium dioxide nanoparticles. Nanoparticle surface modification was performed via two main approaches including post-synthesis and in situ surface modification. The tuneable hydrothermal conditions (i.e. temperature, pressure, flow rates, and surfactant addition) were optimized to enable controlled steric stabilization in a continuous fashion. Effective post synthesis surface modification with organic ligand (dodecenyl succinic anhydride (DDSA)) was achieved; the optimum surface coating temperature was reported to be 180–240 °C to ensure DDSA ring opening

Celiac disease and new diseases related to gluten

Science.gov (United States)

Jiménez Ortega, Ana Isabel; Martínez García, Rosa María; Quiles Blanco, María José; Majid Abu Naji, Jamil Abdel; González Iglesias, María José

2016-07-12

Celiac disease is the most common chronic intestinal disease. Nowadays it´s known that this is a multisistemic pathology of immune mechanism, triggered by gluten, which occurs in genetically susceptible individuals. It affects approximately 1% of the world population, which is a very high prevalence, affects all age groups and has symptoms both digestive and extra-digestive. Since it is a disease that requires maintaining a gluten-free diet and medical monitoring for life, it is important to know it and establish its diagnosis properly. Along with celiac disease a number of new diseases related to gluten are diagnosed increasingly, including the non celiac gluten sensitivity or wheat allergy. The suffering of celiac disease, or other related diseases, by conditioning diet changes of the affected individual, it may be associated with nutritional imbalances that need to monitor and try to solve. Therefore patients with this problem need special nutritional advice.

Novel Foams Based on Freeze-Dried Renewable Vital Wheat Gluten

DEFF Research Database (Denmark)

Blomfeldt, Thomas O.J.; Olsson, Richard T.; Menon, Mohan

2010-01-01

A new way of producing rigid or semi-rigid foams from vital wheat gluten using a freeze-drying process is reported. Water/gluten-based mixtures were frozen and freeze-dried. Different foam structures were obtained by varying the mixing process and wheat gluten concentration, or by adding glycerol...... or bacterial cellulose nanofibers. MIP revealed that the foams had mainly an open porosity peaking at 93%. The average pore diameter ranged between 20 and 73 µm; the sample with the highest wheat gluten concentration and no plasticizer had the smallest pores. Immersion tests with limonene revealed...

Legumes as Functional Ingredients in Gluten-Free Bakery and Pasta Products.

Science.gov (United States)

Foschia, Martina; Horstmann, Stefan W; Arendt, Elke K; Zannini, Emanuele

2017-02-28

The increasing demand for gluten-free food products from consumers has triggered food technologists to investigate a wide range of gluten-free ingredients from different sources to reproduce the unique network structure developed by gluten in a wheat-dough system. In recent times, the attention has been focused on novel application of legume flour or ingredients. The interest in this crop category is mainly attributed to their functional properties, such as solubility and water-binding capacity, which play an important role in gluten-free food formulation and processing. Their nutritional profile may also counteract the lack of nutrients commonly highlighted in commercial gluten-free bakery and pasta products, providing valuable sources of protein, dietary fiber, vitamins, minerals, and complex carbohydrates, which in turn have a positive impact on human health. This review reports the main chemical and functional characteristics of legumes and their functional application in gluten-free products.

Detection of Gluten during the Fermentation Process To Produce Soy Sauce.

Science.gov (United States)

Cao, Wanying; Watson, Damien; Bakke, Mikio; Panda, Rakhi; Bedford, Binaifer; Kande, Parnavi S; Jackson, Lauren S; Garber, Eric A E

2017-04-03

Advances have been made to provide people with celiac disease (CD) access to a diverse diet through an increase in the availability of gluten-free food products and regulations designed to increase label reliability. Despite advances in our knowledge regarding CD and analytical methods to detect gluten, little is known about the effects of fermentation on gluten detection. The enzyme-linked immunosorbent assay (ELISA) and lateral flow devices routinely used by analytical laboratories and regulatory agencies to test for the presence of gluten in food were examined for their ability to detect gluten during the fermentation processes leading to the production of soy sauce, as well as in finished products. Similar results were observed irrespective of whether the soy sauce was produced using pilot-plant facilities or according to a homemade protocol. In both cases, gluten was not detected after moromi (brine-based) fermentation, which is the second stage of fermentation. The inability to detect gluten after moromi fermentation was irrespective of whether the assay used a sandwich configuration that required two epitopes or a competitive configuration that required only one epitope. Consistent with these results was the observation that ELISA, lateral flow devices, and Western immunoblot analyses were unable to detect gluten in commercial soy sauce, teriyaki sauce, and Worcestershire sauce. Although reports are lacking on problems associated with the consumption of fermented soy-containing sauces by consumers with CD, additional research is needed to determine whether all immunopathogenic elements in gluten are hydrolyzed during soy sauce production.

The Clinical Response to Gluten Challenge: A Review of the Literature

Science.gov (United States)

Bruins, Maaike J.

2013-01-01

The aim of this review was to identify, evaluate and summarize all relevant studies reporting on the clinical response to gluten challenge by adult or pediatric patients with suspected or diagnosed coeliac disease (CD) on a gluten-free diet. We evaluated the effect of gluten challenge on changes in symptoms, intestinal mucosa histology, and serum antibodies. A systematic electronic search was performed for studies published as of 1966 using PubMed and Scopus databases. In the reviewed studies, doses ranged from 0.2 to 30 g/day of wheat gluten or comprised a gluten-containing diet. The onset of symptoms upon gluten intake varied largely from days to months and did not parallel serum antibody or histological changes. Within 3 months of gluten challenge, 70%–100% of pediatric CD patients became positive for AGA-IgA and EMA-IgA antibodies and 50%–70% for AGA-IgG. A limited number of trials suggest that no more than half of adult patients developed positive AGA-IgA, EMA-IgA, tTG-IgA or DGP-IgA/IgG titers. Approximately 50%–100% of pediatric and adult patients experienced mucosal relapse of gluten provocation within 3 months, which was preceded by increased mucosal intra-epithelial lymphocytes within several days of challenge. A 3-month high-dose gluten challenge should be suitable to diagnose the majority of CD patients. In some cases prolonged challenge may be needed to verify diagnosis. Combination testing for antibodies and mucosal histology may fasten the diagnosis. PMID:24284613

The Clinical Response to Gluten Challenge: A Review of the Literature

Directory of Open Access Journals (Sweden)

Maaike J. Bruins

2013-11-01

Full Text Available The aim of this review was to identify, evaluate and summarize all relevant studies reporting on the clinical response to gluten challenge by adult or pediatric patients with suspected or diagnosed coeliac disease (CD on a gluten-free diet. We evaluated the effect of gluten challenge on changes in symptoms, intestinal mucosa histology, and serum antibodies. A systematic electronic search was performed for studies published as of 1966 using PubMed and Scopus databases. In the reviewed studies, doses ranged from 0.2 to 30 g/day of wheat gluten or comprised a gluten-containing diet. The onset of symptoms upon gluten intake varied largely from days to months and did not parallel serum antibody or histological changes. Within 3 months of gluten challenge, 70%–100% of pediatric CD patients became positive for AGA-IgA and EMA-IgA antibodies and 50%–70% for AGA-IgG. A limited number of trials suggest that no more than half of adult patients developed positive AGA-IgA, EMA-IgA, tTG-IgA or DGP-IgA/IgG titers. Approximately 50%–100% of pediatric and adult patients experienced mucosal relapse of gluten provocation within 3 months, which was preceded by increased mucosal intra-epithelial lymphocytes within several days of challenge. A 3-month high-dose gluten challenge should be suitable to diagnose the majority of CD patients. In some cases prolonged challenge may be needed to verify diagnosis. Combination testing for antibodies and mucosal histology may fasten the diagnosis.

Non-coeliac gluten or wheat sensitivity: emerging disease or misdiagnosis?

Science.gov (United States)

Potter, Michael DE; Walker, Marjorie M; Talley, Nicholas J

2017-08-04

Non-coeliac gluten or wheat sensitivity (NCG/WS) is a condition characterised by adverse gastrointestinal and/or extra-intestinal symptoms associated with the ingestion of gluten- or wheat-containing foods, in the absence of coeliac disease or wheat allergy. Up to one in 100 people in Australia may have coeliac disease but many more report adverse gastrointestinal and/or extra-intestinal symptoms after eating wheat products. In the absence of validated biomarkers, a diagnosis of NCG/WS can only be made by a double-blind, placebo-controlled, dietary crossover challenge with gluten, which is difficult to apply in clinical practice. Of people self-reporting gluten or wheat sensitivity, only a small proportion (16%) will have reproducible symptoms after a blinded gluten challenge of gluten versus placebo in a crossover dietary trial and fulfil the current consensus criteria for a diagnosis of NCG/WS. A wide range of symptoms are associated with NCG/WS, including gastrointestinal, neurological, psychiatric, rheumatological and dermatological complaints. The pathogenesis of NCG/WS is not well understood, but the innate immune system has been implicated, and there is overlap with coeliac disease and the functional gastrointestinal disorders (irritable bowel syndrome and functional dyspepsia). Identification of NCG/WS is important as gluten-free diets carry risks, are socially restricting and are costlier than regular diets.

A Navier-Stokes phase-field crystal model for colloidal suspensions.

Science.gov (United States)

Praetorius, Simon; Voigt, Axel

2015-04-21

We develop a fully continuous model for colloidal suspensions with hydrodynamic interactions. The Navier-Stokes Phase-Field Crystal model combines ideas of dynamic density functional theory with particulate flow approaches and is derived in detail and related to other dynamic density functional theory approaches with hydrodynamic interactions. The derived system is numerically solved using adaptive finite elements and is used to analyze colloidal crystallization in flowing environments demonstrating a strong coupling in both directions between the crystal shape and the flow field. We further validate the model against other computational approaches for particulate flow systems for various colloidal sedimentation problems.

Removing celiac disease-related gluten proteins from bread wheat while retaining technological properties: a study with Chinese Spring deletion lines.

Science.gov (United States)

van den Broeck, Hetty C; van Herpen, Teun W J M; Schuit, Cees; Salentijn, Elma M J; Dekking, Liesbeth; Bosch, Dirk; Hamer, Rob J; Smulders, Marinus J M; Gilissen, Ludovicus J W J; van der Meer, Ingrid M

2009-04-07

Gluten proteins can induce celiac disease (CD) in genetically susceptible individuals. In CD patients gluten-derived peptides are presented to the immune system, which leads to a CD4+ T-cell mediated immune response and inflammation of the small intestine. However, not all gluten proteins contain T-cell stimulatory epitopes. Gluten proteins are encoded by multigene loci present on chromosomes 1 and 6 of the three different genomes of hexaploid bread wheat (Triticum aestivum) (AABBDD). The effects of deleting individual gluten loci on both the level of T-cell stimulatory epitopes in the gluten proteome and the technological properties of the flour were analyzed using a set of deletion lines of Triticum aestivum cv. Chinese Spring. The reduction of T-cell stimulatory epitopes was analyzed using monoclonal antibodies that recognize T-cell epitopes present in gluten proteins. The deletion lines were technologically tested with respect to dough mixing properties and dough rheology. The results show that removing the alpha-gliadin locus from the short arm of chromosome 6 of the D-genome (6DS) resulted in a significant decrease in the presence of T-cell stimulatory epitopes but also in a significant loss of technological properties. However, removing the omega-gliadin, gamma-gliadin, and LMW-GS loci from the short arm of chromosome 1 of the D-genome (1DS) removed T-cell stimulatory epitopes from the proteome while maintaining technological properties. The consequences of these data are discussed with regard to reducing the load of T-cell stimulatory epitopes in wheat, and to contributing to the design of CD-safe wheat varieties.

Management of Nonceliac Gluten Sensitivity by Gastroenterology Specialists: Data from an Italian Survey

Directory of Open Access Journals (Sweden)

Federica Branchi

2015-01-01

Full Text Available Background and Aim. Nonceliac gluten sensitivity is syndrome characterized by symptoms disappearing after a gluten-free diet. Its existence is still argument of discussion among specialists. Our aim was to evaluate the knowledge about nonceliac gluten sensitivity among gastroenterology specialists. Methods. During October 2013 a questionnaire was sent through a medical newsletter to Italian gastroenterologists. Twelve questions investigated their knowledge on nonceliac gluten sensitivity, including their diagnostic and therapeutic approach. Results. A total of 212 gastroenterologists filled in the questionnaire. The 98.6% were aware of the existence of a syndrome called “nonceliac gluten sensitivity” and 77% believe in its existence. However, only 56% gave a correct definition of the term. The majority of specialists diagnosed gluten sensitive patients and the number of diagnoses was not statistically different from that of celiac disease. Moreover, a gluten-free diet was prescribed by 64% of the specialists and among them the 73% noted an increase of gluten sensitive patients attending their outpatient services. Conclusions. Our study indicated that most of the specialists recognize nonceliac gluten sensitivity and prescribe gluten-free diet, although 44% of the specialists are not able to give its correct definition; underlining the necessity of medical education on this topic is needed.

Colloids in Flatland: a perspective on 2D phase-separated systems, characterisation methods, and lineactant.

NARCIS (Netherlands)

Bernardini, C.; Stoyanov, S.D.; Arnaudov, L.N.; Cohen Stuart, M.A.

2013-01-01

In 1861 Thomas Graham gave birth to a new field of science, today known as colloid science. Nowadays, the notion “colloid” is often used referring to systems consisting of two immiscible phases, one of which is finely dispersed into the other. Research on colloids deals mostly with sols (solids

Part of celiac population still at risk despite current gluten thresholds

NARCIS (Netherlands)

Bruins Slot, I.D.; Bremer, M.G.E.G.; Hamer, R.J.; Fels, van der Ine

2015-01-01

In order to assist celiac disease (CD) patients in making safe food choices, gluten-free food products are labelled as such. The exact meaning of the gluten-free label differs throughout the world. This paper discusses the different thresholds that are currently used to label products gluten-free

Overview on the General Approaches to Improve Gluten-Free Pasta and Bread

Science.gov (United States)

Padalino, Lucia; Conte, Amalia; Del Nobile, Matteo Alessandro

2016-01-01

The use of gluten-free products is increasing since a growing number of people are suffering from celiac disease and thereby need gluten-free diet. Gluten is responsible for the visco-elastic characteristics of wheat-based products; therefore, its lack makes the gluten-free products not similar to wheat-based product, with scarce textural properties. This reason constitutes the major industrial limitation. Thus, obtaining good-quality gluten-free products represents a technological challenge. This review reports the main strategies adopted to produce high quality gluten-free pasta and bread. They are mainly obtained by the utilization of specific ingredients (hydrocolloids, proteins or enzymes) to be incorporated into the standard formulation or the adoption of proper technological variables that can enhance above all the functional properties, the texture and the taste. PMID:28231182

The effect of colloid preload versus prophylactic ephedrine ...

African Journals Online (AJOL)

Aim: We aimed to investigate the effect of colloid infusion immediately before the spinal anesthesia, and the prophylactic intravenous (IV) infusion of ephedrine after injection of intrathecal bupivacaine on hemodynamic parameters, QT, The QT interval corrected for heart rate (QTc), and dispersion of QTc (QTcDisp) intervals ...

Gluten content of barium sulfate suspensions used for barium swallows in patients with celiac disease.

Science.gov (United States)

Chiu, Jennifer G; Shin, Yoona; Patel, Priti N; Mangione, Robert A

2014-01-01

To determine the availability and accuracy of information provided by hospitals, imaging centers, and manufacturers regarding gluten in barium sulfate suspensions. A total of 105 facilities were contacted via telephone to determine the gluten content of the contrast media used in those facilities. Manufacturers were contacted and their Web sites reviewed to determine the gluten content of their barium products. Thirty-nine percent of the hospitals and 52% of the imaging centers were not aware of the gluten content of the contrast media they used. Twenty-nine-and-a-half percent of the respondents provided the correct gluten content. The manufacturers noted that 5 products were tested and confirmed gluten free, 1 product was not tested but described as gluten free, 1 product's gluten content depended upon its flavor, and 1 product was reported to contain gluten. Clinicians caring for patients with celiac disease or patients who choose to restrict their gluten consumption must ensure that the barium sulfate suspension ingested is gluten free. It can be difficult to determine the gluten content of barium sulfate, as a majority of radiology departments and imaging centers did not know whether the product they use is gluten free. Educating staff members and improving product labeling would benefit the quality of care provided to patients with celiac disease.

Proof of concept of microbiome-metabolome analysis and delayed gluten exposure on celiac disease autoimmunity in genetically at-risk infants.

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Maria Sellitto

Full Text Available Celiac disease (CD is a unique autoimmune disorder in which the genetic factors (DQ2/DQ8 and the environmental trigger (gluten are known and necessary but not sufficient for its development. Other environmental components contributing to CD are poorly understood. Studies suggest that aspects of gluten intake might influence the risk of CD occurrence and timing of its onset, i.e., the amount and quality of ingested gluten, together with the pattern of infant feeding and the age at which gluten is introduced in the diet. In this study, we hypothesize that the intestinal microbiota as a whole rather than specific infections dictates the switch from tolerance to immune response in genetically susceptible individuals. Using a sample of infants genetically at risk of CD, we characterized the longitudinal changes in the microbial communities that colonize infants from birth to 24 months and the impact of two patterns of gluten introduction (early vs. late on the gut microbiota and metabolome, and the switch from gluten tolerance to immune response, including onset of CD autoimmunity. We show that infants genetically susceptible to CD who are exposed to gluten early mount an immune response against gluten and develop CD autoimmunity more frequently than at-risk infants in which gluten exposure is delayed until 12 months of age. The data, while derived from a relatively small number of subjects, suggest differences between the developing microbiota of infants with genetic predisposition for CD and the microbiota from infants with a non-selected genetic background, with an overall lack of bacteria of the phylum Bacteriodetes along with a high abundance of Firmicutes and microbiota that do not resemble that of adults even at 2 years of age. Furthermore, metabolomics analysis reveals potential biomarkers for the prediction of CD. This study constitutes a definite proof-of-principle that these combined genomic and metabolomic approaches will be key to

Preparation and Quality Evaluation of Gluten-Free Biscuits

Directory of Open Access Journals (Sweden)

Simona Maria Man

2014-05-01

Full Text Available The aglutenics biscuits are intended to those persons who are suffering due to gluten intolerance, also named celiac disease. The fabrication technologies of the aglutenics products can be developed in on two ways: by separating the gluten from the grain or by replacing the grain flour with other types of gluten less flour, in case of bakery and pastry products. In this experiment, the gluten-free biscuits were obtained from the following flours mixture: maize flour (MF, rice flour (RF and soybeans flour (SF. Other raw materials were used, such as: palmtree oil, honey, maize starch, eggs, sugar powdered, vanilla essence and sodium bicarbonate. Four experimental variants (gluten-free biscuits were obtained by varying the proportion of flours ; these variants were coded as follows T1, T2 T3 and T4. The optimization of the aglutenics biscuits manufacture recipe was realized through sensory analyze, using the hedonic test (9 point scale. Samples of biscuits was subjected to the following physico-chemical analysis: moisture content, alkalinity, total carbohydrate content, total fat and protein content. Also the physical properties (length, width, thickness, weight and spread ratio were determined in order to asses the blending influence on the biscuits quality. The blend with flour levels 30:30:40 (MF:RF:SF led to the highest acceptability.

A radioimmunoassay for wheat gliadin to assess the suitability of gluten free foods for patients with coeliac disease.

Science.gov (United States)

Ciclitira, P J; Ellis, H J; Evans, D J; Lennox, E S

1985-03-01

Coeliac disease is a clinical condition characterised by malabsorption secondary to abnormalities of the small intestine. The condition is known to be exacerbated by wheat gliadin, rye, barley and possibly oats. The only assays that are available for testing for the presence of wheat gluten in foods are double diffusion against rabbit anti-gliadin antiserum and measurement of Kjeldahl nitrogen in products derived from wheat flour. We have developed a radioimmunoassay for wheat gliadin with a detection limit of 1 ng. Nominally gluten free foods based on wheat starch have been shown to contain up to 1.9 X 10(-2)% wheat gliadin. Bread made from Nutregen wheat starch which has now been withdrawn contains 6.4 mg gliadin per standard 30 g slice. A radioimmunoassay for wheat gliadin could be used to define standards for the suitability of gluten free products based on wheat starch for patients with coeliac disease.

Phase behaviour of rod-like colloid + flexible polymer mixtures

NARCIS (Netherlands)

Lekkerkerker, H.N.W.; Stroobants, A.

The effect of non-adsorbing, flexible polymer on the isotropic-nematic transition in dispersions of rod-like colloids is investigated. A widening of the biphasic gap is observed, in combination with a marked polymer partitioning between the coexisting phases. Under certain conditions, areas of

Spectrum of gluten-related disorders: consensus on new nomenclature and classification

Directory of Open Access Journals (Sweden)

Sapone Anna

2012-02-01

Full Text Available Abstract A decade ago celiac disease was considered extremely rare outside Europe and, therefore, was almost completely ignored by health care professionals. In only 10 years, key milestones have moved celiac disease from obscurity into the popular spotlight worldwide. Now we are observing another interesting phenomenon that is generating great confusion among health care professionals. The number of individuals embracing a gluten-free diet (GFD appears much higher than the projected number of celiac disease patients, fueling a global market of gluten-free products approaching $2.5 billion (US in global sales in 2010. This trend is supported by the notion that, along with celiac disease, other conditions related to the ingestion of gluten have emerged as health care concerns. This review will summarize our current knowledge about the three main forms of gluten reactions: allergic (wheat allergy, autoimmune (celiac disease, dermatitis herpetiformis and gluten ataxia and possibly immune-mediated (gluten sensitivity, and also outline pathogenic, clinical and epidemiological differences and propose new nomenclature and classifications.

Removing celiac disease-related gluten proteins from bread wheat while retaining technological properties: a study with Chinese Spring deletion lines

Directory of Open Access Journals (Sweden)

Bosch Dirk

2009-04-01

Full Text Available Abstract Background Gluten proteins can induce celiac disease (CD in genetically susceptible individuals. In CD patients gluten-derived peptides are presented to the immune system, which leads to a CD4+ T-cell mediated immune response and inflammation of the small intestine. However, not all gluten proteins contain T-cell stimulatory epitopes. Gluten proteins are encoded by multigene loci present on chromosomes 1 and 6 of the three different genomes of hexaploid bread wheat (Triticum aestivum (AABBDD. Results The effects of deleting individual gluten loci on both the level of T-cell stimulatory epitopes in the gluten proteome and the technological properties of the flour were analyzed using a set of deletion lines of Triticum aestivum cv. Chinese Spring. The reduction of T-cell stimulatory epitopes was analyzed using monoclonal antibodies that recognize T-cell epitopes present in gluten proteins. The deletion lines were technologically tested with respect to dough mixing properties and dough rheology. The results show that removing the α-gliadin locus from the short arm of chromosome 6 of the D-genome (6DS resulted in a significant decrease in the presence of T-cell stimulatory epitopes but also in a significant loss of technological properties. However, removing the ω-gliadin, γ-gliadin, and LMW-GS loci from the short arm of chromosome 1 of the D-genome (1DS removed T-cell stimulatory epitopes from the proteome while maintaining technological properties. Conclusion The consequences of these data are discussed with regard to reducing the load of T-cell stimulatory epitopes in wheat, and to contributing to the design of CD-safe wheat varieties.

Toward the assessment of food toxicity for celiac patients: characterization of monoclonal antibodies to a main immunogenic gluten peptide.

Directory of Open Access Journals (Sweden)

Belén Morón

Full Text Available BACKGROUND AND AIMS: Celiac disease is a permanent intolerance to gluten prolamins from wheat, barley, rye and, in some patients, oats. Partially digested gluten peptides produced in the digestive tract cause inflammation of the small intestine. High throughput, immune-based assays using monoclonal antibodies specific for these immunotoxic peptides would facilitate their detection in food and enable monitoring of their enzymatic detoxification. Two monoclonal antibodies, G12 and A1, were developed against a highly immunotoxic 33-mer peptide. The potential of each antibody for quantifying food toxicity for celiac patients was studied. METHODS: Epitope preferences of G12 and A1 antibodies were determined by ELISA with gluten-derived peptide variants of recombinant, synthetic or enzymatic origin. RESULTS: The recognition sequences of G12 and A1 antibodies were hexameric and heptameric epitopes, respectively. Although G12 affinity for the 33-mer was superior to A1, the sensitivity for gluten detection was higher for A1. This observation correlated to the higher number of A1 epitopes found in prolamins than G12 epitopes. Activation of T cell from gluten digested by glutenases decreased equivalently to the detection of intact peptides by A1 antibody. Peptide recognition of A1 included gliadin peptides involved in the both the adaptive and innate immunological response in celiac disease. CONCLUSIONS: The sensitivity and epitope preferences of the A1 antibody resulted to be useful to detect gluten relevant peptides to infer the potential toxicity of food for celiac patients as well as to monitor peptide modifications by transglutaminase 2 or glutenases.

Particle Trapping and Banding in Rapid Colloidal Solidification

KAUST Repository

Elliott, J. A. W.

2011-10-11

We derive an expression for the nonequilibrium segregation coefficient of colloidal particles near a moving solid-liquid interface. The resulting kinetic phase diagram has applications for the rapid solidification of clay soils, gels, and related colloidal systems. We use it to explain the formation of bandlike defects in rapidly solidified alumina suspensions. © 2011 American Physical Society.

Anti-gluten immune response following Toxoplasma gondii infection in mice.

Directory of Open Access Journals (Sweden)

Emily G Severance

Full Text Available Gluten sensitivity may affect disease pathogenesis in a subset of individuals who have schizophrenia, bipolar disorder or autism. Exposure to Toxoplasma gondii is a known risk factor for the development of schizophrenia, presumably through a direct pathological effect of the parasite on brain and behavior. A co-association of antibodies to wheat gluten and to T. gondii in individuals with schizophrenia was recently uncovered, suggesting a coordinated gastrointestinal means by which T. gondii and dietary gluten might generate an immune response. Here, we evaluated the connection between these infectious- and food-based antigens in mouse models. BALB/c mice receiving a standard wheat-based rodent chow were infected with T. gondii via intraperitoneal, peroral and prenatal exposure methods. Significant increases in the levels of anti-gluten IgG were documented in all infected mice and in offspring from chronically infected dams compared to uninfected controls (repetitive measures ANOVAs, two-tailed t-tests, all p≤0.00001. Activation of the complement system accompanied this immune response (p≤0.002-0.00001. Perorally-infected females showed higher levels of anti-gluten IgG than males (p≤0.009 indicating that T. gondii-generated gastrointestinal infection led to a significant anti-gluten immune response in a sex-dependent manner. These findings support a gastrointestinal basis by which two risk factors for schizophrenia, T. gondii infection and sensitivity to dietary gluten, might be connected to produce the immune activation that is becoming an increasingly recognized pathology of psychiatric disorders.

Trends in gluten research and its relationship to autoimmune and allergic diseases

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Edward J. Ciaccio

Full Text Available Introduction: Gluten is a protein found in certain grains, and causes an autoimmune response in celiac disease patients. Although the subject of considerable research, gluten research foci and future directions are largely unknown. Methods: The MEDLINE search tool was used to evaluate research trends. For perspective, yearly publications on gluten and other celiac disease reactive proteins were compared to food allergy proteins research. Then the relationship of gluten publications to affiliated keywords was determined. The affiliated keywords belonged to one of several groups: grains, vitamins and minerals, interaction, autoimmunity, genetics, or enzymes. The yearly number of publications in the peer-reviewed medical literature was determined for each relationship from years 1960–2013. The relationships were graphed, and linear regression analysis was used to determine the rate of change in publications per year, and the coefficient of determination. Results: Among celiac disease reactive proteins (gluten, gliadin, and glutenin and selected food allergy proteins (ovalbumin, lysozyme, ovomucoid, and Ara h, gluten showed the greatest rate of increase in published medical research (+20.01 studies/year since 1996, r2=0.97. Additionally, there were sharp increases in the rate of gluten research publications per year in association with keywords ‘autoimmunity’ (+7.69 studies/year since 1997, ‘wheat’ (+6.08 studies/year since 1999, and ‘transglutaminase’ enzyme (+5.05 studies/year since 1995. The longest running moderate trend was research on ‘gluten’ and ‘antibodies’ (+2.50 studies/year, r2=0.92 since 1971. Conclusions: Research on gluten as a reactive protein is of rapidly growing interest in the medical literature. MEDLINE is helpful to determine foci and future directions. Keywords: Celiac disease, Gluten, Gliadin, Medline, Transglutaminase

The effect of gluten on the host-microbial metabolism assessed by urinary metabolomics

DEFF Research Database (Denmark)

Roager, Henrik Munch; Frandsen, Henrik Lauritz; Gøbel, Rikke Juul

A gluten-free diet clearly improves the life of patients with celiac disease, but the scientific evidence supporting possible health benefits of a gluten-free diet for non-celiac adults is limited. Therefore, as urine reflects the host and gut microbial metabolism, the study aimed to assess...... a gluten-rich (21.6±5.7g/day) or a gluten-poor (~1g/day) diet for 8 weeks, crossing over to the other diet after 6 weeks washout. Urine samples were standardised collected at the beginning and end of each diet intervention period and were analysed by gas chromatography mass spectrometry (GC-MS) and liquid...... the long-term metabolic effect of gluten on the urine metabolome of non-celiac individuals by a cross-over intervention study (gluten-poor and gluten rich, respectively) using a non-targeted metabolomics approach. Fifty-one non-celiac adult participants (30 female, 21 male) were randomized to either...

QUALITY OF GLUTEN-FREE BUCKWHEAT-RICE BREAD

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Petra Dvořáková

2013-02-01

Full Text Available In case of celiac disease the products containing gluten must be excluded from the nutrition. The offer of gluten-free products (especially pastry is low and in addition the gluten-free breads are typical of dry crust and crumb and higher firmness in comparison with wheat bread. This work deals with gluten-free mixtures prepared from buckwheat and rice flour and the effect of rising amount of these flours on bread quality, crumb hardness, elasticity, chewiness and gumminess. With rising portion of buckwheat flour in the mixture the bread volume, dough and bread yield increased. The biggest improvement was found for mean bread volume (30% between the samples FO 1090 (166.7 cm3 and FO 9010 (216.7 cm3. The texture analysis showed positive effect of rice flour on hardness, chewiness and gumminess. Hardness decreased from 114.5 N (F 100 to 91.3 N (FO 1090. Very similar results showed chewiness and gumminess. Chewiness of F 100 (314.0 was reduced by 32.5% to 212.2 at the sample FO 1090. Gumminess was improved almost linearly through the samples, the biggest difference (44.3% was found between the check sample F 100 (88.3 and FO 1090 (49.7.

Photochemical Synthesis and Properties of Colloidal Copper, Silver and Gold Adsorbed on Quartz

International Nuclear Information System (INIS)

Loginov, Anatoliy V.; Gorbunova, Valentina V.; Boitsova, Tatiana B.

2002-01-01

Original methods for the photochemical production of stable copper, silver and gold colloids in the form of films on quartz, and dispersion in liquids were devised. It is shown that photochemical synthesis of colloidal metals is a difficult multiphase process, and includes the formation of low-valence forms of Cu(I), Au(I) and nonmetal clusters, colloidal particles and their agglomerates. Cluster stabilization and further growth to colloidal particles are achieved by adsorption onto the solid surface (quartz) or by increasing the viscosity of photolyte. In the absence of these methods of stabilization, the processes of intermediate reoxidation to Cu(II) and Au(III) and agglomeration of Ag and Au colloids proceed in a photolyte. Adsorption and the rate of cluster growth on a quartz surface are speeded up by the action of monochromatic UV light. Experimental models of the mechanism of colloidal formation are suggested. The dependence of the growth rate and the properties of the colloids on conditions of the photochemical procedure (energy and light intensity, concentration of initial complex) has been established

Grain Quality Evaluation and Characterization of Gluten Powder ...

African Journals Online (AJOL)

The aim of this research was to study the grain quality, proximate composition, gluten isolation and characterization of three bread wheat varieties namely Pavon 76, HAR 2501 and HAR 2536 grown in Arsi and Bale areas of Ethiopia. The wheat varieties had a protein content of 10.60, 11.53 and 10.70% while the wet gluten ...

Gluten Intolerance: Sex- and Age-Related Features

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MJ Llorente-Alonso

2006-01-01

Full Text Available OBJECTIVE: Gluten intolerance is an immune-mediated enteropathy associated with gluten-containing foods in genetically susceptible patients. The typical form mainly affecting children shows failure to thrive and/or gastrointestinal symptoms. The adult form is less typical, presenting vague gastrointestinal symptoms, iron deficiency (with or without anemia or nonspecific serum chemistry abnormalities. The present study aims to analyze clinical and biochemical differences of celiac disease (CD according to sex and age.

On the effects from the simultaneous occurrence of the critical Casimir and dispersion forces between conical colloid particle and a thick plate immersed in nonpolar critical fluid

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Valchev Galin

2018-01-01

Full Text Available Here we study the interplay between the van der Waals (vdWF and critical Casimir forces (CCF, as well as the total force (TF between a conical colloid particle and a thick planar slab. We do that using general scaling arguments and mean-field type calculations utilizing the so-called “surface integration approach”, a generalization of the well known Derjaguin approximation. Its usage in the present research, requires knowledge on the forces between two parallel slabs, confining in between some fluctuating fluid medium characterized by its temperature T and chemical potential μ. The surfaces of the colloid particle and the slab are assumed coated by thin layers exerting strong preference to the liquid phase of a simple fluid, or one of the components of a binary mixture, modeled by strong adsorbing local surface potentials, ensuring the so-called (+,+ boundary conditions. On the other hand, the core region of the slab and the particle, influence the fluid by long-ranged competing dispersion potentials. We demonstrate that for a suitable set of colloid-fluid, slab-fluid, and fluid-fluid coupling parameters the competition between the effects due to the coatings and the core regions of the objects, result, when one changes T or μ, in sign change of the Casimir force (CF and the TF acting between the colloid and the slab. Such an effect can provide a strategy for solving problems with handling, feeding, trapping and fixing of microparts in nanotechnology.

Physical aging and structural recovery in a colloidal glass subjected to volume-fraction jump conditions

Science.gov (United States)

Peng, Xiaoguang; McKenna, Gregory B.

2016-04-01

Three important kinetic phenomena have been cataloged by Kovacs in the investigation of molecular glasses during structural recovery or physical aging. These are responses to temperature-jump histories referred to as intrinsic isotherms, asymmetry of approach, and memory effect. Here we use a thermosensitive polystyrene-poly (N -isopropylacrylamide)-poly (acrylic acid) core-shell particle-based dispersion as a colloidal model and by working at a constant number concentration of particles we use temperature changes to create volume-fraction changes. This imposes conditions similar to those defined by Kovacs on the colloidal system. We use creep experiments to probe the physical aging and structural recovery behavior of colloidal glasses in the Kovacs-type histories and compare the results with those seen in molecular glasses. We find that there are similarities in aging dynamics between molecular glasses and colloidal glasses, but differences also persist. For the intrinsic isotherms, the times teq needed for relaxing or evolving into the equilibrium (or stationary) state are relatively insensitive to the volume fraction and the values of teq are longer than the α -relaxation time τα at the same volume fraction. On the other hand, both of these times grow at least exponentially with decreasing temperature in molecular glasses. For the asymmetry of approach, similar nonlinear behavior is observed for both colloidal and molecular glasses. However, the equilibration time teq is the same for both volume-fraction up-jump and down-jump experiments, different from the finding in molecular glasses that it takes longer for the structure to evolve into equilibrium for the temperature up-jump condition than for the temperature down-jump condition. For the two-step volume-fraction jumps, a memory response is observed that is different from observations of structural recovery in two-step temperature histories in molecular glasses. The concentration dependence of the dynamics

Testing for Gluten-Related Disorders in Clinical Practice: The Role of Serology in Managing the Spectrum of Gluten Sensitivity

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David Armstrong

2011-01-01

Full Text Available Immunoglobulin A tissue transglutaminase is the single most efficient serological test for the diagnosis of celiac disease. It is well known that immunoglobulin A tissue transglutaminase levels correlate with the degree of intestinal damage, and that values can fluctuate in patients over time. Serological testing can be used to identify symptomatic individuals that need a confirmatory biopsy, to screen at-risk populations or to monitor diet compliance in patients previously diagnosed with celiac disease. Thus, interpretation of serological testing requires consideration of the full clinical scenario. Antigliadin tests are no longer recommended for the diagnosis of classical celiac disease. However, our understanding of the pathogenesis and spectrum of gluten sensitivity has improved, and gluten-sensitive irritable bowel syndrome patients are increasingly being recognized. Studies are needed to determine the clinical utility of antigliadin serology in the diagnosis of gluten sensitivity.

Diagnosis and classification of celiac disease and gluten sensitivity.

Science.gov (United States)

Tonutti, Elio; Bizzaro, Nicola

2014-01-01

Celiac disease is a complex disorder, the development of which is controlled by a combination of genetic (HLA alleles) and environmental (gluten ingestion) factors. New diagnostic guidelines developed by ESPGHAN emphasize the crucial role of serological tests in the diagnostic process of symptomatic subjects, and of the detection of HLA DQ2/DQ8 alleles in defining a diagnosis in asymptomatic subjects belonging to at-risk groups. The serological diagnosis of CD is based on the detection of class IgA anti-tissue transglutaminase (anti-tTG) and anti-endomysial antibodies. In patients with IgA deficiency, anti-tTG or anti-deamidated gliadin peptide antibody assays of the IgG class are used. When anti-tTG antibody levels are very high, antibody specificity is absolute and CD can be diagnosed without performing a duodenum biopsy. Non-celiac gluten sensitivity is a gluten reaction in which both allergic and autoimmune mechanisms have been ruled out. Diagnostic criteria include the presence of symptoms similar to those of celiac or allergic patients; negative allergological tests and absence of anti-tTG and EMA antibodies; normal duodenal histology; evidence of disappearance of the symptoms with a gluten-free diet; relapse of the symptoms when gluten is reintroduced. Copyright © 2014 Elsevier B.V. All rights reserved.

Effects of relaxation of gluten network on rehydration kinetics of pasta.

Science.gov (United States)

Ogawa, Takenobu; Hasegawa, Ayako; Adachi, Shuji

2014-01-01

The aim of this study was to investigate the effects of the relaxation of the gluten network on pasta rehydration kinetics. The moisture content of pasta, under conditions where the effects of the diffusion of water on the moisture content were negligible, was estimated by extrapolating the average moisture content of pasta of various diameters to 0 mm. The moisture content of imaginary, infinitely thin pasta did not reach equilibrium even after 1 h of rehydration. The rehydration of pasta made of only gluten was also measured. The rate constants estimated by the Long and Richman equation for both the pasta indicated that the rehydration kinetics of infinitely thin pasta were similar to those of gluten pasta. These results suggest that the swelling of starch by fast gelatinization was restricted by the honeycomb structural network of gluten and the relaxation of the gluten network controlled pasta rehydration kinetics.

Nutritional and sensory challenges of gluten-free bakery products: a review.

Science.gov (United States)

Stantiall, Sophie E; Serventi, Luca

2018-06-01

There is a growing need for gluten-free bakery products. Currently, gluten-free bakery products deliver lower protein, fibre and mineral content and elevated glycaemic index (GI) than gluten-containing foods. Only a mixture of rice and buckwheat flour or a low addition of either egg white or whey protein, has shown potential for the improvement of both nutrition and sensory qualities. To increase the fibre content, isolated cereal fibre and soluble fibre isolates have been incorporated into gluten-free formulations with some sensory success. Studies have shown that the GI of modern gluten-free products is no longer a major concern with the improvement of ingredient formulations and processing methods. The currently low mineral content can be increased with the use of mineral-rich ingredients such as amaranth, buckwheat or flaxseed flour. Nonetheless, consumers still show a preference to refined, low fibre breads over wholegrain fibre-rich bread.

A radioimmunoassay for wheat gliadin to assess the suitability of gluten free foods for patients with coeliac disease

International Nuclear Information System (INIS)

Ciclitira, P.J.; Ellis, H.J.; Evans, D.J.; Lennox, E.S.

1985-01-01

Coeliac disease is a clinical condition characterised by malabsorption secondary to abnormalities of the small intestine. The condition is known to be exacerbated by wheat gliadin, rye, barley and possibly oats. The only assays that are available for testing for the presence of wheat gluten in foods are double diffusion against rabbit anti-gliadin antiserum and measurement of Kjeldahl nitrogen in products derived from wheat flour. We have developed a radioimmunoassay for wheat gliadin with a detection limit of 1 ng. Nominally gluten free foods based on wheat starch have been shown to contain up to 1.9x10 -2 % wheat gliadin. Bread made from Nutregen wheat starch which has now been withdrawn contains 6.4 mg gliadin per standard 30 g slice. A radioimmunoassay for wheat gliadin could be used to define standards for the suitability of gluten free products based on wheat starch for patients with coeliac disease. (author)

Groundwater colloids: Their mobilization from subsurface deposits. Final report

International Nuclear Information System (INIS)

1998-01-01

The overall goal of this program has involved developing basic understandings of the mechanisms controlling the presence of colloidal phases in groundwaters. The presence of colloids in groundwater is extremely important in that they may enable the subsurface transport of otherwise immobile pollutants like plutonium or PCBs. The major findings of this work have included: (1) Sampling groundwaters must be performed with great care in order to avoid false positives; (2) Much of the colloidal load moving below ground derives from the aquifer solids themselves; and (3) The detachment of colloids from the aquifer solids occurs in response to changes in the groundwater solution chemistry

Synthesis of nanosized silver colloids by microwave dielectric heating

Indian Academy of Sciences (India)

Silver nanosized crystallites have been synthesized in aqueous and polyols viz., ethylene glycol and glycerol, using a microwave technique. Dispersions of colloidal silver have been prepared by the reduction of silver nitrate both in the presence and absence of stabilizer poly(vinylpyrolidone) (PVP). It was observed that ...

Regional enteritis and gluten-free diet. A clinical study

NARCIS (Netherlands)

Merwe, Christiaan Frederik van der

1974-01-01

The purpose of this clinical study was to determine whether the use of a gluten-free diet influenced the course and prognosis of regional enteritis. Following a few clinical communications in the Dutch medical literature reporting favourable results obtained with the gluten-free diet in the

Gluten Unu İlavesinin Hamurun Reolojik Özellikleri ve Ekmeğin Kalitesine Etkisi

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Hazım Özkaya

2015-02-01

Full Text Available Farklı özellikteki iki un örneğinden laboratuvarda elde edilen değişik özellikteki gluten unları ile bir nişasta fabrikası yan ürünü olan ticari gluten unu 74 ve 80 randımanlı unlara %1, %3, %5, %7 ve %10 oranlarında katılarak hamurun reolojik özellikleri ve ekmeğin kalitesine etkileri araştırılmıştır. Gluten unu katılan örneklerin farinograftaki su absorbsiyonları yükselmiştir. Gelişme süresi 50 oC de kurutulan gluten unlarından olumlu yönde etkilenmiştir. Stabilite değeri, yoğurma tolerans sayısı, yumuşama derecesi ve valorimetre değeri laboratuvarda elde edilen gluten unlarından olumlu, ticari gluten unundan ise olumsuz yönde etkilenmiştir. Ekstensografta hamurun uzama mukavemeti una gluten unu katıldığı zaman artmıştır. Hamurun uzama kabiliyeti 70 oC de kurutulan gluten unu katılmış örneklerde azalmıştır. Enerji değeri ise 70 oC de kurutulan gluten unu ve %10 ticari gluten unu katkılı örnekler dışında olumlu yönde etkilenmiştir. Ekmek hacmi ve değer sayısı, 50 oC de kurutulan gluten unundan olumlu, 70 oC de kurutulandan ise olumsuz yönde etkilenmiştir. Ticari gluten unu 80 randımanlı unların ekmek hacmi ve değer sayısını arttırmıştır.

Non-celiac gluten sensitivity (NCGS – an old diagnosis recently rediscovered

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Kamil K. Hozyasz

2016-02-01

Full Text Available Non-celiac gluten sensitivity (NCGS is a newly recognised clinical entity by academic medical professionals, but it is better to consider it an old diagnosis recently rediscovered. The overall prevalence of NCGS in the general population is currently unknown largely because patients often self-diagnose and place themselves on the celiac-type gluten-free diet (GFD without medical supervision. NCGS is an umbrella term and may incorporate different subgroups of patients. Now there is no specific biomarker that can be used to identify the entity. NCGS diagnosis can be reached only by excluding celiac disease and wheat allergy. Symptoms must disappear with the withdrawal of gluten and reappear quickly when gluten is reintroduced. NCGS existence has been recently supported by two expert meetings, however mechanisms by which gluten triggers symptoms, mimicking irritable bowel syndrome and skin rashes, numbness,”foggy mind”, disturbed sleep patterns, have yet to be identified. Knowledge about NCGS natural history and outcome is still lacking. NCNG is the entity awaiting better diagnostics criteria, however a dietary approach for the management of patients with gastrointestinal symptoms and lack of well being no longer seems elusive. There is a growing segment of the population that seeks out gluten-free products because of a wider notion that gluten-free constitutes a healthier option. Major area of concern that must be addressed by medical professionals is the high cost of GFD.

A study on the characteristics of colloid-associated radionuclide transport in porous media

International Nuclear Information System (INIS)

Jeong, Yun Chang

1997-02-01

Recently, the radionuclide transport in the form of colloids has been focused intensively in the safety assessment of a radioactive waste repository. As colloids are considered to be able to increase the transport rate of radionuclide through geologic media, the transport of radionuclide should be adjusted by the presence of colloids. The migration of dissolved radionuclide is expected to depend on various process such as advection, dispersion and interactions with soils, and, in addition, the transport of colloid-mediated radionuclide is considered to be more complicated because of the interactions between radionuclides and colloids. In this paper the migration behavior of colloid-associated radionuclides within subsurface are reviewed and studied in detail. The colloid-mediated transport system was modelled and simulated in order to illustrate the effects of colloids on the transport of radionuclide in the aquifer system. The transport rate of radionuclide is mainly controlled by a retardation factor which is controlled by colloidal behaviors, degree of adsorption, and the related geologic parameters. Therefore it is necessary to carefully understand the accelerating tendency of the retardation difference factor, and in this study the trends are analyzed, described and the retardation difference factor is mathematically defined, simplified and applied practically to the safety and performance assessment of a future repository

Simultaneous transport of synthetic colloids and a nonsorbing solute through single saturated natural fractures

International Nuclear Information System (INIS)

Reimus, P.W.; Robinson, B.A.; Nuttall, H.E.; Kale, R.

1994-01-01

Tracer transport experiments involving colloids that showed little tendency to attach to rock surfaces and a nonsorbing solute (iodide) -were conducted in three different well-characterized natural fractures in tuff. The colloids always arrived earlier in the effluent than the iodide, which we believe is evidence of (1) hydrodynamic chromatography and/or (2) the fact that the colloids experience a smaller effective volume in the fracture because they diffuse too slowly to enter low-velocity regions (dead zones) along the rough fracture walls. The iodide also approached the inlet concentration in the effluent more slowly than the colloids, with the concentration at a given elution volume being greater at higher flow rates. By contrast, the rate of approach of the colloid concentration to the inlet concentration did not vary with flow rate. We attribute this behavior to matrix diffusion of the iodide, with the colloids being too large/nondiffusive to experience this phenomenon. Dispersion of all tracers was greatest in the fracture of widest average aperture and least in the fracture of narrowest aperture, which is consistent with Taylor dispersion theory. The tracer experiments were modeled/interpreted using a three-step approach that involved (1) estimating the aperture distribution in each fracture using surface profiling techniques, (2) predicting the flow field in the fractures using a localized parallel-plate approximation, and (3) predicting tracer transport in the fractures using particle-tracking techniques. Although considered preliminary at this time, the model results were in qualitative agreement with the experiments

Dispersion for the preparation of an injectable radiopharmaceutical scanning agent

International Nuclear Information System (INIS)

Wolfangel, R.G.

1976-01-01

The invention deals with the preparation of a dispersion of a tin (II) sulphur colloid in an aqueous solution with additions of a stabilizing agent. Labelled with sup(99m)Tc, the dispersion can be used as an injectable radiopharmaceutical scanning agent. (VJ) [de

Ineffective Degradation of Immunogenic Gluten Epitopes by Currently Available Digestive Enzyme Supplements

Science.gov (United States)

Janssen, George; Christis, Chantal; Kooy-Winkelaar, Yvonne; Edens, Luppo; Smith, Drew

2015-01-01

Background Due to the high proline content of gluten molecules, gastrointestinal proteases are unable to fully degrade them leaving large proline-rich gluten fragments intact, including an immunogenic 33-mer from α-gliadin and a 26-mer from γ-gliadin. These latter peptides can trigger pro-inflammatory T cell responses resulting in tissue remodeling, malnutrition and a variety of other complications. A strict lifelong gluten-free diet is currently the only available treatment to cope with gluten intolerance. Post-proline cutting enzymes have been shown to effectively degrade the immunogenic gluten peptides and have been proposed as oral supplements. Several existing digestive enzyme supplements also claim to aid in gluten degradation. Here we investigate the effectiveness of such existing enzyme supplements in comparison with a well characterized post-proline cutting enzyme, Prolyl EndoPeptidase from Aspergillus niger (AN-PEP). Methods Five commercially available digestive enzyme supplements along with purified digestive enzymes were subjected to 1) enzyme assays and 2) mass spectrometric identification. Gluten epitope degradation was monitored by 1) R5 ELISA, 2) mass spectrometric analysis of the degradation products and 3) T cell proliferation assays. Findings The digestive enzyme supplements showed comparable proteolytic activities with near neutral pH optima and modest gluten detoxification properties as determined by ELISA. Mass spectrometric analysis revealed the presence of many different enzymes including amylases and a variety of different proteases with aminopeptidase and carboxypeptidase activity. The enzyme supplements leave the nine immunogenic epitopes of the 26-mer and 33-mer gliadin fragments largely intact. In contrast, the pure enzyme AN-PEP effectively degraded all nine epitopes in the pH range of the stomach at much lower dose. T cell proliferation assays confirmed the mass spectrometric data. Conclusion Currently available digestive enzyme

Ineffective degradation of immunogenic gluten epitopes by currently available digestive enzyme supplements.

Directory of Open Access Journals (Sweden)

George Janssen

Full Text Available Due to the high proline content of gluten molecules, gastrointestinal proteases are unable to fully degrade them leaving large proline-rich gluten fragments intact, including an immunogenic 33-mer from α-gliadin and a 26-mer from γ-gliadin. These latter peptides can trigger pro-inflammatory T cell responses resulting in tissue remodeling, malnutrition and a variety of other complications. A strict lifelong gluten-free diet is currently the only available treatment to cope with gluten intolerance. Post-proline cutting enzymes have been shown to effectively degrade the immunogenic gluten peptides and have been proposed as oral supplements. Several existing digestive enzyme supplements also claim to aid in gluten degradation. Here we investigate the effectiveness of such existing enzyme supplements in comparison with a well characterized post-proline cutting enzyme, Prolyl EndoPeptidase from Aspergillus niger (AN-PEP.Five commercially available digestive enzyme supplements along with purified digestive enzymes were subjected to 1 enzyme assays and 2 mass spectrometric identification. Gluten epitope degradation was monitored by 1 R5 ELISA, 2 mass spectrometric analysis of the degradation products and 3 T cell proliferation assays.The digestive enzyme supplements showed comparable proteolytic activities with near neutral pH optima and modest gluten detoxification properties as determined by ELISA. Mass spectrometric analysis revealed the presence of many different enzymes including amylases and a variety of different proteases with aminopeptidase and carboxypeptidase activity. The enzyme supplements leave the nine immunogenic epitopes of the 26-mer and 33-mer gliadin fragments largely intact. In contrast, the pure enzyme AN-PEP effectively degraded all nine epitopes in the pH range of the stomach at much lower dose. T cell proliferation assays confirmed the mass spectrometric data.Currently available digestive enzyme supplements are ineffective in

Microbial Proteases in Baked Goods: Modification of Gluten and Effects on Immunogenicity and Product Quality

Directory of Open Access Journals (Sweden)

Nina G. Heredia-Sandoval

2016-08-01

Full Text Available Gluten-related diseases are a range of inflammatory disorders of the small intestine, characterized by an adverse response to gluten ingestion; therefore, the treatment is a gluten withdrawal. In spite of the increased market of gluten-free products, widely available breads with high acceptability are still missing due to the technological challenge of substituting the special gluten properties. Instead of using alternative ingredients for baking, some attempts have been done to decrease gluten immunogenicity by its enzymatic degradation with microbial proteases. Although the gluten immunogenicity reduction has been reached to an acceptable level, some quality parameters of the products are affected. This review focus on the use of microbial peptidases to prepare less immunogenic baked goods and their effect on product quality.

Microbial Proteases in Baked Goods: Modification of Gluten and Effects on Immunogenicity and Product Quality.

Science.gov (United States)

Heredia-Sandoval, Nina G; Valencia-Tapia, Maribel Y; Calderón de la Barca, Ana M; Islas-Rubio, Alma R

2016-08-30

Gluten-related diseases are a range of inflammatory disorders of the small intestine, characterized by an adverse response to gluten ingestion; therefore, the treatment is a gluten withdrawal. In spite of the increased market of gluten-free products, widely available breads with high acceptability are still missing due to the technological challenge of substituting the special gluten properties. Instead of using alternative ingredients for baking, some attempts have been done to decrease gluten immunogenicity by its enzymatic degradation with microbial proteases. Although the gluten immunogenicity reduction has been reached to an acceptable level, some quality parameters of the products are affected. This review focus on the use of microbial peptidases to prepare less immunogenic baked goods and their effect on product quality.

Optimization of corn, rice and buckwheat formulations for gluten-free wafer production.

Science.gov (United States)

Dogan, Ismail Sait; Yildiz, Onder; Meral, Raciye

2016-07-01

Gluten-free baked products for celiac sufferers are essential for healthy living. Cereals having gluten such as wheat and rye must be removed from the diet for the clinical and histological improvement. The variety of gluten-free foods should be offered for the sufferers. In the study, gluten-free wafer formulas were optimized using corn, rice and buckwheat flours, xanthan and guar gum blend as an alternative product for celiac sufferers. Wafer sheet attributes and textural properties were investigated. Considering all wafer sheet properties in gluten-free formulas, better results were obtained by using 163.5% water, 0.5% guar and 0.1% xanthan in corn formula; 173.3% water, 0.45% guar and 0.15% xanthan gum in rice formula; 176% water, 0.1% guar and 0.5% xanthan gum in buckwheat formula. Average desirability values in gluten-free formulas were between 0.86 and 0.91 indicating they had similar visual and textural profiles to control sheet made with wheat flour. © The Author(s) 2015.

Rheological Properties of Gluten Free Dough Systems

OpenAIRE

Tandazo, Stephany Aurea

2013-01-01

Bread is the one of the oldest processed foods and a major wheat based product. The basic process involves mixing of ingredients until the flour is converted into dough, followed by baking the dough into a loaf. A very important step in breadmaking is to know how to make good quality dough. However, the increasing knowledge of people being diagnosed with celiac disease (gluten intolerance) has encouraged scientists to develop healthier and better quality gluten-free products that would greatl...

Effects of gliadin addition on the rheological, microscopic and thermal characteristics of wheat gluten.

Science.gov (United States)

Khatkar, B S; Barak, Sheweta; Mudgil, Deepak

2013-02-01

In the present study, micro-structural, thermal and rheological changes in the gluten network upon addition of gliadins at 5% and 10% levels were investigated using scanning electron microscopy (SEM), thermo gravimetric analysis (TGA), differential scanning calorimetry (DSC) and dynamic rheometry. The addition of gliadins decreased the peak dough height inferring decrease in dough strength. The dough stability also decreased from 3.20 to 1.40 min upon addition of 10% gliadin to the base flour. The TGA profile and the glass transition behavior of the control gluten and gluten obtained from dough with gliadin added at 5% and 10% levels showed decrease in thermal stability. The SEM micrograph of the control gluten showed foam like protein matrix. As the gliadin percentage in the gluten was increased, the compactness of the gluten structure reduced considerably leading to the formation of a more open weak gluten network. Copyright © 2012 Elsevier B.V. All rights reserved.

Effect of Lupine Flour on Baking Characteristics of Gluten Free Cookies

OpenAIRE

Sofyan Maghaydah; Selma Abdul-hussain; Radwan Ajo; Yousef Tawalbeh; Noor Elsahoryi

2013-01-01

Celiac Disease (CD) is an immune-mediated disease in genetically susceptible individuals caused by intolerance to gluten protein in some cereals, resulting in mucosal inflammation, which causes malabsorption. An effective treatment for CD is a gluten-free diet that excludes cereals containing gluten. One of the most desirable wheat products is the cookie, which is considered suitable for all ages due to its low manufacturing cost, convenience, long shelf life and good eating quality. Therefor...

Comparative efficiency of different methods of gluten extraction in indigenous varieties of wheat.

Science.gov (United States)

Imran, Samra; Hussain, Zaib; Ghafoor, Farkhanda; Nagra, Saeedahmad; Ziai, Naheeda Ashbeal

2013-06-01

The present study investigated six varieties of locally grown wheat (Lasani, Sehar, Miraj-08, Chakwal-50, Faisalabad-08 and Inqlab) procured from Punjab Seed Corporation, Lahore, Pakistan for their proximate contents. On the basis of protein content and ready availability, Faisalabad-08 (FD-08) was selected to be used for the assessment of comparative efficiency of various methods used for gluten extraction. Three methods, mechanical, chemical and microbiological were used for the extraction of gluten from FD-08. Each method was carried out under ambient conditions using a drying temperature of 55 degrees C. Mechanical method utilized four different processes viz:- dough process, dough batter process, batter process and ethanol washing process using standard 150 mesh. The starch thus obtained was analyzed for its proximate contents. Dough batter process proved to be the most efficient mechanical method and was further investigated using 200 and 300 mesh. Gluten content was determined using sandwich omega-gliadin enzyme-linked immunosorbent assay (ELISA).The results of dough batter process using 200 mesh indicated a starch product with gluten content of 678 ppm. Chemical method indicated high gluten content of more than 5000 ppm and the microbiological method reduced the gluten content from 2500 ppm to 398 ppm. From the results it was observed that no gluten extraction method is viable to produce starch which can fulfill the criteria of a gluten free product (20 ppm).

Diagnosis of Non-Celiac Gluten Sensitivity (NCGS: The Salerno Experts’ Criteria

Directory of Open Access Journals (Sweden)

Carlo Catassi

2015-06-01

Full Text Available Non-Celiac Gluten Sensitivity (NCGS is a syndrome characterized by intestinal and extra-intestinal symptoms related to the ingestion of gluten-containing food, in subjects that are not affected by either celiac disease or wheat allergy. Given the lack of a NCGS biomarker, there is the need for standardizing the procedure leading to the diagnosis confirmation. In this paper we report experts’ recommendations on how the diagnostic protocol should be performed for the confirmation of NCGS. A full diagnostic procedure should assess the clinical response to the gluten-free diet (GFD and measure the effect of a gluten challenge after a period of treatment with the GFD. The clinical evaluation is performed using a self-administered instrument incorporating a modified version of the Gastrointestinal Symptom Rating Scale. The patient identifies one to three main symptoms that are quantitatively assessed using a Numerical Rating Scale with a score ranging from 1 to 10. The double-blind placebo-controlled gluten challenge (8 g/day includes a one-week challenge followed by a one-week washout of strict GFD and by the crossover to the second one-week challenge. The vehicle should contain cooked, homogeneously distributed gluten. At least a variation of 30% of one to three main symptoms between the gluten and the placebo challenge should be detected to discriminate a positive from a negative result. The guidelines provided in this paper will help the clinician to reach a firm and positive diagnosis of NCGS and facilitate the comparisons of different studies, if adopted internationally.

Size- and composition-dependent toxicity of synthetic and soil-derived Fe oxide colloids for the nematode Caenorhabditis elegans.

Science.gov (United States)

Höss, Sebastian; Fritzsche, Andreas; Meyer, Carolin; Bosch, Julian; Meckenstock, Rainer U; Totsche, Kai Uwe

2015-01-06

Colloidal iron oxides (FeOx) are increasingly released to the environment due to their use in environmental remediation and biomedical applications, potentially harming living organisms. Size and composition could affect the bioavailability and toxicity of such colloids. Therefore, we investigated the toxicity of selected FeOx with variable aggregate size and variably composed FeOx-associated organic matter (OM) toward the nematode Caenorhabditis elegans. Ferrihydrite colloids containing citrate were taken up by C. elegans with the food and accumulated inside their body. The toxicity of ferrihydrite, goethite, and akaganeite was dependent on aggregate size and specific surface area, with EC50 values for reproduction ranging from 4 to 29 mg Fe L(-1). Experiments with mutant strains lacking mitochondrial superoxide dismutase (sod-2) showed oxidative stress for two FeOx and Fe(3+)-ions, however, revealed that it was not the predominant mechanism of toxicity. The OM composition determined the toxicity of mixed OM-FeOx phases on C. elegans. FeOx associated with humic acids or citrate were less toxic than OM-free FeOx. In contrast, soil-derived ferrihydrite, containing proteins and polysaccharides from mobile OM, was even more toxic than OM-free Fh of similar aggregate size. Consequently, the careful choice of the type of FeOx and the type of associated OM may help in reducing the ecological risks if actively applied to the subsurface.

Controlled synthesis of colloidal silver nanoparticles in capillary micro-flow reactor

International Nuclear Information System (INIS)

He Shengtai; Liu Yulan; Maeda, Hideaki

2008-01-01

In this study, using a polytetrafluoroethylene (PTFE) capillary tube as a micro-flow reactor, well-dispersed colloidal silver nanoparticles were controllably synthesized with different flow rates of precursory solution. Scanning transmission electron microscopy images and UV-visible absorbance spectra showed that silver nanoparticles with large size can be prepared with slow flow rate in the PTFE capillary reactor. The effects of tube diameters on the growth of colloidal silver nanoparticles were investigated. Experiment results demonstrated that using tube with small diameter was more propitious for the controllable synthesis of silver nanoparticles with different sizes.

[Effects of dietary wheat gluten level on decreasing plasma homocysteine concentration in rats].

Science.gov (United States)

Liu, Yiqun; Han, Feng; Sun, Licui; Lu, Jiaxi; Sugiyama, Kimio; Huang, Zhenwu

2015-05-01

To investigate the effects of different level of casein and wheat gluten on decreasing plasma homocysteine concentration in rats. 48 rats of the Wistar were fed with different level of casein (12.5%, 25% and 50%) and wheat gluten (14.5%, 29% and 58%) diets for 14 days, and they were killed by decapitation to obtain blood and livers was subject to analysis the concentration of homocysteine, cysteine and other amino acids, as well as BHMT and CBS activities. Body weight gain in rats fed wheat gluten dietary was significantly less than casein dietary, but food intake was significantly decreased in wheat gluten group with increasing of the protein content. The plasma homocysteine concentration in rats fed wheat gluten was marketly less than casein, however plasma cysteine concentration in wheat gluten was higher than casein group. The effects of wheat gluten on plasma homocysteine concentration are mainly depends on the low contents of methionine and high cysteine content, but the low contents of lyscine and threonine are not ignored. The mainly mechanism is that the increased cysteine concentration promot enzyme activities of homocystein metabolism, and increase the consumption of homocysteine.

THE STUDYING OF COLLOIDAL-CHEMICAL PROPERTIES OF CLAY MINERALS DISPERSIONS

Directory of Open Access Journals (Sweden)

A. F. Tymchuk

2015-02-01

Full Text Available The element structure is studied, the microscopic analysis of fine-dispersed min­eral systems (ground sediments of a mouth of the river Danube is carried out. The sedimentation process of clay minerals dispersions in solutions of surfactants and macromolecular substances is studied. Concentration intervals of stabilization of investigating dispersions were defined.

Functional replacements for gluten

NARCIS (Netherlands)

Zannini, E.; Jones, J.M.; Renzetti, S.; Arendt, E.K.

2012-01-01

Celiac disease (CD) is an immune-mediated disease triggered in genetically susceptible individuals by ingested gluten from wheat, rye, barley, and other closely related cereal grains. Currently, the only therapy able to normalize the clinical and histological manifestation of the disease is a strict

The Effects of a Gluten-free Diet Versus a Hypocaloric Diet Among Patients With Fibromyalgia Experiencing Gluten Sensitivity-like Symptoms: A Pilot, Open-Label Randomized Clinical Trial.

Science.gov (United States)

Slim, Mahmoud; Calandre, Elena P; Garcia-Leiva, Juan M; Rico-Villademoros, Fernando; Molina-Barea, Rocio; Rodriguez-Lopez, Carmen M; Morillas-Arques, Piedad

2017-07-01

Patients with fibromyalgia frequently present with symptoms similar to those experienced by patients with gluten-related disorders, raising the possibility that a subgroup of these patients could be experiencing underlying gluten sensitivity. This study aimed to evaluate the effects of a gluten-free diet (GFD) compared with a hypocaloric diet (HCD) among patients with fibromyalgia. Adult patients diagnosed with fibromyalgia were randomly allocated to receive a GFD or a HCD over a 24-week period. The primary outcome measure was the change in the number of gluten sensitivity symptoms. The following secondary outcomes were evaluated: body mass index, Revised Fibromyalgia Impact Questionnaire, Pittsburgh Sleep Quality Index, Brief Pain Inventory, Beck Depression Inventory-II, State-Trait Anxiety Inventory, Short-Form Health Survey, Patient Global Impression Scale of Severity, Patient Global Impression Scale of Improvement, and adverse events. Seventy-five subjects were randomly allocated to receive either a GFD (n=35) or an HCD (n=40). The least squares mean change in the total number of gluten sensitivity symptoms from baseline did not differ significantly between the GFD and HCD groups (-2.44±0.40 for the GFD; -2.10±0.37 for the HCD; P=0.343). Similarly, the 2 dietary interventions did not differ in any of the remaining measured secondary outcomes. Both dietary interventions were well tolerated. Both dietary interventions were associated with similar beneficial outcomes in reducing gluten sensitivity symptoms and other secondary outcomes. However, despite its specificity, GFD was not superior to HCD in reducing the number of gluten sensitivity symptoms or secondary outcomes.

The preferred substrates for transglutaminase 2 in a complex wheat gluten digest are Peptide fragments harboring celiac disease T-cell epitopes.

Directory of Open Access Journals (Sweden)

Siri Dørum

Full Text Available BACKGROUND: Celiac disease is a T-cell mediated chronic inflammatory disorder of the gut that is induced by dietary exposure to gluten proteins. CD4+ T cells of the intestinal lesion recognize gluten peptides in the context of HLA-DQ2.5 or HLA-DQ8 and the gluten derived peptides become better T-cell antigens after deamidation catalyzed by the enzyme transglutaminase 2 (TG2. In this study we aimed to identify the preferred peptide substrates of TG2 in a heterogeneous proteolytic digest of whole wheat gluten. METHODS: A method was established to enrich for preferred TG2 substrates in a complex gluten peptide mixture by tagging with 5-biotinamido-pentylamine. Tagged peptides were isolated and then identified by nano-liquid chromatography online-coupled to tandem mass spectrometry, database searching and final manual data validation. RESULTS: We identified 31 different peptides as preferred substrates of TG2. Strikingly, the majority of these peptides were harboring known gluten T-cell epitopes. Five TG2 peptide substrates that were predicted to bind to HLA-DQ2.5 did not contain previously characterized sequences of T-cell epitopes. Two of these peptides elicited T-cell responses when tested for recognition by intestinal T-cell lines of celiac disease patients, and thus they contain novel candidate T-cell epitopes. We also found that the intact 9mer core sequences of the respective epitopes were not present in all peptide substrates. Interestingly, those epitopes that were represented by intact forms were frequently recognized by T cells in celiac disease patients, whereas those that were present in truncated versions were infrequently recognized. CONCLUSION: TG2 as well as gastrointestinal proteolysis play important roles in the selection of gluten T-cell epitopes in celiac disease.

The Preferred Substrates for Transglutaminase 2 in a Complex Wheat Gluten Digest Are Peptide Fragments Harboring Celiac Disease T-Cell Epitopes

Science.gov (United States)

Dørum, Siri; Arntzen, Magnus Ø.; Qiao, Shuo-Wang; Holm, Anders; Koehler, Christian J.; Thiede, Bernd; Sollid, Ludvig M.; Fleckenstein, Burkhard

2010-01-01

Background Celiac disease is a T-cell mediated chronic inflammatory disorder of the gut that is induced by dietary exposure to gluten proteins. CD4+ T cells of the intestinal lesion recognize gluten peptides in the context of HLA-DQ2.5 or HLA-DQ8 and the gluten derived peptides become better T-cell antigens after deamidation catalyzed by the enzyme transglutaminase 2 (TG2). In this study we aimed to identify the preferred peptide substrates of TG2 in a heterogeneous proteolytic digest of whole wheat gluten. Methods A method was established to enrich for preferred TG2 substrates in a complex gluten peptide mixture by tagging with 5-biotinamido-pentylamine. Tagged peptides were isolated and then identified by nano-liquid chromatography online-coupled to tandem mass spectrometry, database searching and final manual data validation. Results We identified 31 different peptides as preferred substrates of TG2. Strikingly, the majority of these peptides were harboring known gluten T-cell epitopes. Five TG2 peptide substrates that were predicted to bind to HLA-DQ2.5 did not contain previously characterized sequences of T-cell epitopes. Two of these peptides elicited T-cell responses when tested for recognition by intestinal T-cell lines of celiac disease patients, and thus they contain novel candidate T-cell epitopes. We also found that the intact 9mer core sequences of the respective epitopes were not present in all peptide substrates. Interestingly, those epitopes that were represented by intact forms were frequently recognized by T cells in celiac disease patients, whereas those that were present in truncated versions were infrequently recognized. Conclusion TG2 as well as gastrointestinal proteolysis play important roles in the selection of gluten T-cell epitopes in celiac disease. PMID:21124911

Non‐celiac gluten sensitivity : a real disease?

OpenAIRE

Fernandes, Inês Cristina Ferreira

2016-01-01

Trabalho Final do Curso de Mestrado Integrado em Medicina, Faculdade de Medicina, Universidade de Lisboa, 2016 The past years have seen an increase in the use of a gluten-­‐free diet (GFD) outside a diagnosis of coeliac disease (CD) or wheat allergy (WA). This trend has led to the identification of a new clinical entity termed non-­‐celiac gluten sensitivity (NCGS), which has clinical features that overlap with those two previously mentioned. The onset of symptoms in patients with NCGS can...

Crust formation in drying colloidal suspensions

KAUST Repository

Style, R. W.; Peppin, S. S. L.

2010-01-01

and the equations of poroelasticity, while the equations of colloid physics govern processes in the suspension. We derive new equations describing this process, including unique boundary conditions coupling the two regions, yielding a moving-boundary model

Use of nuclear recoil for separating 228Ra, 224Ra, and 233Pa from colloidal thorium

International Nuclear Information System (INIS)

Beydon, J.; Gratot, I.

1968-01-01

By using α-recoil it is possible to separate by dialysis the α disintegration products (224 Ra; 228 Ra) of thorium from colloidal thorium hydroxide.The use of n, γ recoil allows the separation of 233 Pa produced by the neutron irradiation of thorium, on condition that the colloidal thorium hydroxide is irradiated in the presence of a dispersing. (author) [fr

Colloidal mobilization of arsenic from mining-affected soils by surface runoff.

Science.gov (United States)

Gomez-Gonzalez, Miguel Angel; Voegelin, Andreas; Garcia-Guinea, Javier; Bolea, Eduardo; Laborda, Francisco; Garrido, Fernando

2016-02-01

Scorodite-rich wastes left as a legacy of mining and smelting operations pose a threat to environmental health. Colloids formed by the weathering of processing wastes may control the release of arsenic (As) into surface waters. At a former mine site in Madrid (Spain), we investigated the mobilization of colloidal As by surface runoff from weathered processing wastes and from sediments in the bed of a draining creek and a downstream sedimentation-pond. Colloids mobilized by surface runoff during simulated rain events were characterized for their composition, structure and mode of As uptake using asymmetric flow field-flow fractionation coupled to inductively plasma mass spectrometry (AF4-ICP-MS) and X-ray absorption spectroscopy (XAS) at the As and Fe K-edges. Colloidal scorodite mobilized in surface runoff from the waste pile is acting as a mobile As carrier. In surface runoff from the river bed and the sedimentation pond, ferrihydrite was identified as the dominant As-bearing colloidal phase. The results from this study suggest that mobilization of As-bearing colloids by surface runoff may play an important role in the dispersion of As from metallurgical wastes deposited above ground and needs to be considered in risk assessment. Copyright © 2015 Elsevier Ltd. All rights reserved.

Dietary gluten reduces the number of intestinal regulatory T cells in mice

DEFF Research Database (Denmark)

Ejsing-Duun, Maria; Josephsen, Jytte; Aasted, Bent

2008-01-01

It is well established that gluten-free diet reduces the incidence of type 1 diabetes mellitus (T1D) in non-obese diabetic (NOD) mice, though the mechanism is not known. However, regulatory T cells (Treg) are likely to play an important role. Also, it is known that dietary gluten induces...... of female NOD and BALB / c mice of 3 week old were fed either a gluten-free diet or a standard diet. Lactococcus garvieae or saline water was administered per oral to one of each dietary group. Spleen and Peyer's patches were sampled from BALB / c mice for flow cytometric monitoring of IL-10 and Treg. NOD...... mice were diagnosed diabetic with blood glucose level >12 mmol / l. Dietary gluten significantly decreased the occurrence of Tregs by 10-15% (P diet. These results and the diabetes incidence were independent of the gluten-induced bacterial factor...

Detection of gluten immunogenic peptides in the urine of patients with coeliac disease reveals transgressions in the gluten-free diet and incomplete mucosal healing.

Science.gov (United States)

Moreno, María de Lourdes; Cebolla, Ángel; Muñoz-Suano, Alba; Carrillo-Carrion, Carolina; Comino, Isabel; Pizarro, Ángeles; León, Francisco; Rodríguez-Herrera, Alfonso; Sousa, Carolina

2017-02-01

Gluten-free diet (GFD) is the only management for coeliac disease (CD). Available methods to assess GFD compliance are insufficiently sensitive to detect occasional dietary transgressions that may cause gut mucosal damage. We aimed to develop a method to determine gluten intake and monitor GFD compliance in patients with CD and to evaluate its correlation with mucosal damage. Urine samples of 76 healthy subjects and 58 patients with CD subjected to different gluten dietary conditions were collected. A lateral flow test (LFT) with the highly sensitive and specific G12 monoclonal antibody for the most dominant gluten immunogenic peptides (GIP) and a LFT reader were used to quantify GIP in solid-phase extracted urines. GIP were detectable in concentrated urines from healthy individuals previously subjected to GFD as early as 4-6 h after single gluten intake, and remained detectable for 1-2 days. The urine assay revealed infringement of the GFD in about 50% of the patients. Analysis of duodenal biopsies revealed that most of patients with CD (89%) with no villous atrophy had no detectable GIP in urine, while all patients with quantifiable GIP in urine showed incomplete intestinal mucosa recovery. GIP are detected in urine after gluten consumption, enabling a new and non-invasive method to monitor GFD compliance and transgressions. The method was sensitive, specific and simple enough to be convenient for clinical monitoring of patients with CD as well as for basic and clinical research applications including drug development. NCT02344758. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

Pair mobility functions for rigid spheres in concentrated colloidal dispersions: Force, torque, translation, and rotation.

Science.gov (United States)

Zia, Roseanna N; Swan, James W; Su, Yu

2015-12-14

The formulation of detailed models for the dynamics of condensed soft matter including colloidal suspensions and other complex fluids requires accurate description of the physical forces between microstructural constituents. In dilute suspensions, pair-level interactions are sufficient to capture hydrodynamic, interparticle, and thermodynamic forces. In dense suspensions, many-body interactions must be considered. Prior analytical approaches to capturing such interactions such as mean-field approaches replace detailed interactions with averaged approximations. However, long-range coupling and effects of concentration on local structure, which may play an important role in, e.g., phase transitions, are smeared out in such approaches. An alternative to such approximations is the detailed modeling of hydrodynamic interactions utilizing precise couplings between moments of the hydrodynamic traction on a suspended particle and the motion of that or other suspended particles. For two isolated spheres, a set of these functions was calculated by Jeffrey and Onishi [J. Fluid Mech. 139, 261-290 (1984)] and Jeffrey [J. Phys. Fluids 4, 16-29 (1992)]. Along with pioneering work by Batchelor, these are the touchstone for low-Reynolds-number hydrodynamic interactions and have been applied directly in the solution of many important problems related to the dynamics of dilute colloidal dispersions [G. K. Batchelor and J. T. Green, J. Fluid Mech. 56, 375-400 (1972) and G. K. Batchelor, J. Fluid Mech. 74, 1-29 (1976)]. Toward extension of these functions to concentrated systems, here we present a new stochastic sampling technique to rapidly calculate an analogous set of mobility functions describing the hydrodynamic interactions between two hard spheres immersed in a suspension of arbitrary concentration, utilizing accelerated Stokesian dynamics simulations. These mobility functions provide precise, radially dependent couplings of hydrodynamic force and torque to particle translation

Pair mobility functions for rigid spheres in concentrated colloidal dispersions: Force, torque, translation, and rotation

International Nuclear Information System (INIS)

Zia, Roseanna N.; Su, Yu; Swan, James W.

2015-01-01

The formulation of detailed models for the dynamics of condensed soft matter including colloidal suspensions and other complex fluids requires accurate description of the physical forces between microstructural constituents. In dilute suspensions, pair-level interactions are sufficient to capture hydrodynamic, interparticle, and thermodynamic forces. In dense suspensions, many-body interactions must be considered. Prior analytical approaches to capturing such interactions such as mean-field approaches replace detailed interactions with averaged approximations. However, long-range coupling and effects of concentration on local structure, which may play an important role in, e.g., phase transitions, are smeared out in such approaches. An alternative to such approximations is the detailed modeling of hydrodynamic interactions utilizing precise couplings between moments of the hydrodynamic traction on a suspended particle and the motion of that or other suspended particles. For two isolated spheres, a set of these functions was calculated by Jeffrey and Onishi [J. Fluid Mech. 139, 261–290 (1984)] and Jeffrey [J. Phys. Fluids 4, 16–29 (1992)]. Along with pioneering work by Batchelor, these are the touchstone for low-Reynolds-number hydrodynamic interactions and have been applied directly in the solution of many important problems related to the dynamics of dilute colloidal dispersions [G. K. Batchelor and J. T. Green, J. Fluid Mech. 56, 375–400 (1972) and G. K. Batchelor, J. Fluid Mech. 74, 1–29 (1976)]. Toward extension of these functions to concentrated systems, here we present a new stochastic sampling technique to rapidly calculate an analogous set of mobility functions describing the hydrodynamic interactions between two hard spheres immersed in a suspension of arbitrary concentration, utilizing accelerated Stokesian dynamics simulations. These mobility functions provide precise, radially dependent couplings of hydrodynamic force and torque to particle

Learn about gluten-free diets

Science.gov (United States)

... gluten-free, including: Fruits and vegetables Meat, fish, poultry, and eggs Beans Nuts and seeds Dairy products ... including frozen foods, soups, and rice mixes Salad dressings, sauces, marinades, and gravies Some candies, licorice Some ...

Saturated Zone Colloid-Facilitated Transport

International Nuclear Information System (INIS)

Wolfsberg, A.; Reimus, P.

2001-01-01

and interpretation from the C-wells reactive tracer testing complex in the saturated zone of Yucca Mountain. As no data regarding colloid transport have been developed by the Yucca Mountain Site Characterization Project (YMP) for the alluvial system, a theoretical analysis based on studies performed in other alluvial systems is developed. The parameters derived in this AMR are developed in a manner consistent with the PA methodology and can be readily integrated into that analysis

The Gluten-Free Diet: Can Oats and Wheat Starch Be Part of It?

Science.gov (United States)

Poley, J Rainer

2017-01-01

Objective and Conclusion: Uncertainty still exists about the use of oats and wheat starch as part of a gluten-free diet in patients with celiac disease (CD). This review should help to clarify the issues at hand. Whereas uncontaminated (from gluten/gliadin) oats and oats from cultivars not containing celiac-activating sequences of proline and glutamine can be used without risk of intestinal damage, wheat starch should not be used, unless it is free of gluten-that is, deglutinized-because even small amounts of gluten over time are able to induce small intestinal mucosal damage.

Low incidence of spontaneous type 1 diabetes in non-obese diabetic mice raised on gluten-free diets is associated with changes in the intestinal microbiome.

Science.gov (United States)

Marietta, Eric V; Gomez, Andres M; Yeoman, Carl; Tilahun, Ashenafi Y; Clark, Chad R; Luckey, David H; Murray, Joseph A; White, Bryan A; Kudva, Yogish C; Rajagopalan, Govindarajan

2013-01-01

Human and animal studies strongly suggest that dietary gluten could play a causal role in the etiopathogenesis of type 1 diabetes (T1D). However, the mechanisms have not been elucidated. Recent reports indicate that the intestinal microbiome has a major influence on the incidence of T1D. Since diet is known to shape the composition of the intestinal microbiome, we investigated using non-obese diabetic (NOD) mice whether changes in the intestinal microbiome could be attributed to the pro- and anti-diabetogenic effects of gluten-containing and gluten-free diets, respectively. NOD mice were raised on gluten-containing chows (GCC) or gluten-free chows (GFC). The incidence of diabetes was determined by monitoring blood glucose levels biweekly using a glucometer. Intestinal microbiome composition was analyzed by sequencing 16S rRNA amplicons derived from fecal samples. First of all, GCC-fed NOD mice had the expected high incidence of hyperglycemia whereas NOD mice fed with a GFC had significantly reduced incidence of hyperglycemia. Secondly, when the fecal microbiomes were compared, Bifidobacterium, Tannerella, and Barnesiella species were increased (p = 0.03, 0.02, and 0.02, respectively) in the microbiome of GCC mice, where as Akkermansia species was increased (p = 0.02) in the intestinal microbiomes of NOD mice fed GFC. Thirdly, both of the gluten-free chows that were evaluated, either egg white based (EW-GFC) or casein based (C-GFC), significantly reduced the incidence of hyperglycemia. Interestingly, the gut microbiome from EW-GFC mice was similar to C-GFC mice. Finally, adding back gluten to the gluten-free diet reversed its anti-diabetogenic effect, reduced Akkermansia species and increased Bifidobacterium, Tannerella, and Barnesiella suggesting that the presence of gluten is directly responsible for the pro-diabetogenic effects of diets and it determines the gut microflora. Our novel study thus suggests that dietary gluten could modulate the incidence of

Surface self-assembly of fluorosurfactants during film formation of MMA/nBA colloidal dispersions.

Science.gov (United States)

Dreher, W R; Urban, M W

2004-11-23

These studies focus on the behavior of fluorosurfactants (FS) containing hydrophobic and ionic entities in the presence of methyl methacrylate/n-butyl acrylate (MMA/nBA) colloidal dispersions stabilized by sodium dodecyl sulfate (SDS). The presence of FS significantly not only alters the mobility of SDS in MMA/nBA films, but their hydrophobic and ionic nature results in self-assembly near the film-air (F-A) interface leading to different surface morphologies. Spherical islands and rodlike morphologies are formed which diminish the kinetic coefficient of friction of films by at least 3 orders of magnitude, and the presence of dual hydrophobic tails and an anionic head appears to have the largest effect on the surface friction. Using internal reflection IR imaging, these studies show that structural and chemical features of FS are directly related to their ability to migrate to the F-A interface and self-assemble to form specific morphological features. While the anionic nature of FS allows for SDS migration to the F-A interface and the formation of stable domains across the surface, intermolecular cohesion of nonionic FS allows for the formation of rodlike structures due to inability to form mixed micelles with SDS. These studies also establish the relationship between surface morphologies, kinetic coefficient of friction, and structural features of surfactants in the complex environments.

Active colloids

International Nuclear Information System (INIS)

Aranson, Igor S

2013-01-01

A colloidal suspension is a heterogeneous fluid containing solid microscopic particles. Colloids play an important role in our everyday life, from food and pharmaceutical industries to medicine and nanotechnology. It is useful to distinguish two major classes of colloidal suspensions: equilibrium and active, i.e., maintained out of thermodynamic equilibrium by external electric or magnetic fields, light, chemical reactions, or hydrodynamic shear flow. While the properties of equilibrium colloidal suspensions are fairly well understood, active colloids pose a formidable challenge, and the research is in its early exploratory stage. One of the most remarkable properties of active colloids is the possibility of dynamic self-assembly, a natural tendency of simple building blocks to organize into complex functional architectures. Examples range from tunable, self-healing colloidal crystals and membranes to self-assembled microswimmers and robots. Active colloidal suspensions may exhibit material properties not present in their equilibrium counterparts, e.g., reduced viscosity and enhanced self-diffusivity, etc. This study surveys the most recent developments in the physics of active colloids, both in synthetic and living systems, with the aim of elucidation of the fundamental physical mechanisms governing self-assembly and collective behavior. (physics of our days)

Interaction mechanisms of condensed tannins (proanthocyanidins) with wheat gluten proteins

Science.gov (United States)

Proanthocyanidins (PA) crosslink wheat gluten, increasing its polymer size and strength. However, precise mechanisms behind these interactions are unknown. This study used PA of different MW profiles (mDP 8.3 and 19.5) to investigate the interactions involved in PA polymerization of gluten. The high...

Evaluation of commercial gluten-free foods from the Brazilian market

Science.gov (United States)

In addition to Celiac Disease, there are other gluten related disorders classified according to immunological response, e.g. autoimmune, allergic and sensitivity (non-autoimmune and non-allergic). In all cases, the only effective therapy is strict adherence to a gluten free diet, which consists of a...

Tailoring particle size and morphology of colloidal Ag particles via chemical precipitation for Ag-BSCCO composites

International Nuclear Information System (INIS)

Medendorp, N.W. Jr.; Bowman, K.J.; Trumble, K.P.

1996-01-01

The chemical precipitation of silver particles is an effective method for tailoring the particle size and morphology. This article investigates a chemical precipitation method for producing silver colloids, and how processing parameters affected particle size, morphology and adherence. Decreasing the silver nitrate concentration during precipitation with sodium borohydride decreased the colloidal silver particle size. Decreasing the addition rate of the reducing agent produced faceted particles. Reversing the reactant addition order also changed the particle size and the morphology. Precipitated colloids demonstrated a difference between the growth-dominated and the equilibrium structures. Co-dispersing Bi-based superconducting platelets during precipitation allowed Ag colloids to preferentially nucleate on the platelets and to remain adhered even after the additional processing. (orig.)

Living with coeliac disease and a gluten-free diet: a Canadian perspective.

Science.gov (United States)

Zarkadas, M; Dubois, S; MacIsaac, K; Cantin, I; Rashid, M; Roberts, K C; La Vieille, S; Godefroy, S; Pulido, O M

2013-02-01

Strict adherence to a gluten-free diet is the only treatment for coeliac disease. The gluten-free diet is complex, costly and impacts on all activities involving food, making it difficult to maintain for a lifetime. The purpose of this cross-sectional study was to evaluate the difficulties experienced, the strategies used and the emotional impact of following a gluten-free diet among Canadians with coeliac disease. A questionnaire was mailed to all members (n = 10 693) of both the Canadian Celiac Association and the Fondation québécoise de la maladie cœliaque in 2008. The overall response rate was 72%. Results are presented for the 5912 respondents (≥18 years) reporting biopsy-confirmed coeliac disease and/or dermatitis herpetiformis. Two-thirds never intentionally consumed gluten. Women reported significantly greater emotional responses to a gluten-free diet but, with time, were more accepting of it than men. Difficulties and negative emotions were experienced less frequently by those on the diet for >5 years, although food labelling and eating away from home remained very problematic. Frustration and isolation because of the diet were the most common negative emotions experienced. The present study quantifies the difficulties experienced, the strategies used and the emotional impact of following a gluten-free diet. It highlights the need to improve the training and education of dietitians, other health providers and the food service industry workers about coeliac disease and a gluten-free diet, with the aim of better helping individuals improve their adherence to a gluten-free diet and their quality of life. © 2012 Canadian Celiac Association and Food Directorate Health Canada Journal of Human Nutrition and Dietetics © 2012 The British Dietetic Association Ltd.

Re-challenge Studies in Non-celiac Gluten Sensitivity: A Systematic Review and Meta-Analysis

Directory of Open Access Journals (Sweden)

Elena Lionetti

2017-09-01

Full Text Available Background: Non-celiac gluten sensitivity (NCGS is a clinical entity characterized by intestinal and/or extra-intestinal symptoms related to the ingestion of gluten in individuals that are not affected by either celiac disease (CD or wheat allergy (WA. Since we do not have specific biomarkers for NCGS, the diagnosis is based on the evidence of a clear relationship between the ingestion of gluten (re-challenge and clinical symptoms, after a remission during the gluten-free diet (GFD. Several re-challenge studies have been published so far to evaluate the real prevalence of NCGS, reporting conflicting results. In the present article, we provide a systematic review with meta-analysis of the existing literature on re-challenge studies to evaluate prevalence figures of NCGS after re-challenge procedures.Methods: All clinical trials performing a gluten re-challenge with or without a placebo control in patients with a suspected diagnosis of NCGS were included. Search results were limited to studies published in English language. No publication date or publication status restrictions were imposed.Results: Eleven studies were included in the meta-analysis. There was a considerable heterogeneity related to different sample size, type, and amount of gluten administered, duration of challenge and different type of placebo. The overall pooled percentage of patients with a diagnosis of NCGS relapsing after a gluten challenge was 30%, ranging between 7 and 77%. The meta-analysis showed a not significant relative risk (RR of relapse after gluten challenge as compared to placebo (RR = 0.4; 95% CI = −0.15–0.9; p = 0.16. The overall pooled percentage of patients with a diagnosis of NCGS relapsing after a gluten challenge performed according to the recent Salerno criteria was significantly higher as compared to the percentage of patients relapsing after placebo (40 vs. 24%; p = 0.003, with a significant RR of relapse after gluten challenge as compared to

Dispersions of Goethite Nanorods in Aprotic Polar Solvents

Directory of Open Access Journals (Sweden)

Delphine Coursault

2017-10-01

Full Text Available Colloidal suspensions of anisotropic nanoparticles can spontaneously self-organize in liquid-crystalline phases beyond some concentration threshold. These phases often respond to electric and magnetic fields. At lower concentrations, usual isotropic liquids are observed but they can display very strong Kerr and Cotton-Mouton effects (i.e., field-induced particle orientation. For many examples of these colloidal suspensions, the solvent is water, which hinders most electro-optic applications. Here, for goethite (α-FeOOH nanorod dispersions, we show that water can be replaced by polar aprotic solvents, such as N-methyl-2-pyrrolidone (NMP and dimethylsulfoxide (DMSO, without loss of colloidal stability. By polarized-light microscopy, small-angle X-ray scattering and electro-optic measurements, we found that the nematic phase, with its field-response properties, is retained. Moreover, a strong Kerr effect was also observed with isotropic goethite suspensions in these polar aprotic solvents. Furthermore, we found no significant difference in the behavior of both the nematic and isotropic phases between the aqueous and non-aqueous dispersions. Our work shows that goethite nanorod suspensions in polar aprotic solvents, suitable for electro-optic applications, can easily be produced and that they keep all their outstanding properties. It also suggests that this solvent replacement method could be extended to the aqueous colloidal suspensions of other kinds of charged anisotropic nanoparticles.

Colloidal organization

CERN Document Server

Okubo, Tsuneo

2015-01-01

Colloidal Organization presents a chemical and physical study on colloidal organization phenomena including equilibrium systems such as colloidal crystallization, drying patterns as an example of a dissipative system and similar sized aggregation. This book outlines the fundamental science behind colloid and surface chemistry and the findings from the author's own laboratory. The text goes on to discuss in-depth colloidal crystallization, gel crystallization, drying dissipative structures of solutions, suspensions and gels, and similar-sized aggregates from nanosized particles. Special emphas

Colloidal graphite/graphene nanostructures using collagen showing enhanced thermal conductivity

Science.gov (United States)

Bhattacharya, Soumya; Dhar, Purbarun; Das, Sarit K; Ganguly, Ranjan; Webster, Thomas J; Nayar, Suprabha

2014-01-01

In the present study, the exfoliation of natural graphite (GR) directly to colloidal GR/graphene (G) nanostructures using collagen (CL) was studied as a safe and scalable process, akin to numerous natural processes and hence can be termed “biomimetic”. Although the exfoliation and functionalization takes place in just 1 day, it takes about 7 days for the nano GR/G flakes to stabilize. The predominantly aromatic residues of the triple helical CL forms its own special micro and nanoarchitecture in acetic acid dispersions. This, with the help of hydrophobic and electrostatic forces, interacts with GR and breaks it down to nanostructures, forming a stable colloidal dispersion. Surface enhanced Raman spectroscopy, X-ray diffraction, photoluminescence, fluorescence, and X-ray photoelectron spectroscopy of the colloid show the interaction between GR and CL on day 1 and 7. Differential interference contrast images in the liquid state clearly reveal how the GR flakes are entrapped in the CL fibrils, with a corresponding fluorescence image showing the intercalation of CL within GR. Atomic force microscopy of graphene-collagen coated on glass substrates shows an average flake size of 350 nm, and the hexagonal diffraction pattern and thickness contours of the G flakes from transmission electron microscopy confirm ≤ five layers of G. Thermal conductivity of the colloid shows an approximate 17% enhancement for a volume fraction of less than approximately 0.00005 of G. Thus, through the use of CL, this new material and process may improve the use of G in terms of biocompatibility for numerous medical applications that currently employ G, such as internally controlled drug-delivery assisted thermal ablation of carcinoma cells. PMID:24648728

Colloidal graphite/graphene nanostructures using collagen showing enhanced thermal conductivity.

Science.gov (United States)

Bhattacharya, Soumya; Dhar, Purbarun; Das, Sarit K; Ganguly, Ranjan; Webster, Thomas J; Nayar, Suprabha

2014-01-01

In the present study, the exfoliation of natural graphite (GR) directly to colloidal GR/graphene (G) nanostructures using collagen (CL) was studied as a safe and scalable process, akin to numerous natural processes and hence can be termed "biomimetic". Although the exfoliation and functionalization takes place in just 1 day, it takes about 7 days for the nano GR/G flakes to stabilize. The predominantly aromatic residues of the triple helical CL forms its own special micro and nanoarchitecture in acetic acid dispersions. This, with the help of hydrophobic and electrostatic forces, interacts with GR and breaks it down to nanostructures, forming a stable colloidal dispersion. Surface enhanced Raman spectroscopy, X-ray diffraction, photoluminescence, fluorescence, and X-ray photoelectron spectroscopy of the colloid show the interaction between GR and CL on day 1 and 7. Differential interference contrast images in the liquid state clearly reveal how the GR flakes are entrapped in the CL fibrils, with a corresponding fluorescence image showing the intercalation of CL within GR. Atomic force microscopy of graphene-collagen coated on glass substrates shows an average flake size of 350 nm, and the hexagonal diffraction pattern and thickness contours of the G flakes from transmission electron microscopy confirm ≤ five layers of G. Thermal conductivity of the colloid shows an approximate 17% enhancement for a volume fraction of less than approximately 0.00005 of G. Thus, through the use of CL, this new material and process may improve the use of G in terms of biocompatibility for numerous medical applications that currently employ G, such as internally controlled drug-delivery assisted thermal ablation of carcinoma cells.

Heteroaggregation of titanium dioxide nanoparticles with natural clay colloids.

Science.gov (United States)

Labille, Jérôme; Harns, Carrie; Bottero, Jean-Yves; Brant, Jonathan

2015-06-02

To better understand and predict the fate of engineered nanoparticles in the water column, we assessed the heteroaggregation of TiO2 nanoparticles with a smectite clay as analogues for natural colloids. Heteroaggregation was evaluated as a function of water salinity (10(-3) and 10(-1) M NaCl), pH (5 and 8), and selected nanoparticle concentration (0-4 mg/L). Time-resolved laser diffraction was used, coupled to an aggregation model, to identify the key mechanisms and variables that drive the heteroaggregation of the nanoparticles with colloids. Our data show that, at a relevant concentration, nanoparticle behavior is mainly driven by heteroaggregation with colloids, while homoaggregation remains negligible. The affinity of TiO2 nanoparticles for clay is driven by electrostatic interactions. Opposite surface charges and/or high ionic strength favored the formation of primary heteroaggregates via the attachment of nanoparticles to the clay. The initial shape and dispersion state of the clay as well as the nanoparticle/clay concentration ratio also affected the nature of the heteroaggregation mechanism. With dispersed clay platelets (10(-3) M NaCl), secondary heteroaggregation driven by bridging nanoparticles occurred at a nanoparticle/clay number ratio of greater than 0.5. In 10(-1) M NaCl, the clay was preaggregated into larger and more spherical units. This favored secondary heteroaggregation at lower nanoparticle concentration that correlated to the nanoparticle/clay surface area ratio. In this latter case, a nanoparticle to clay sticking efficiency could be determined.

EDITORIAL: Colloidal suspensions Colloidal suspensions

Science.gov (United States)

Petukhov, Andrei; Kegel, Willem; van Duijneveldt, Jeroen

2011-05-01

fluid-fluid interface [2]. Together with Remco Tuinier, Henk has recently completed a book in this area which is to appear later this year. A major theme in Henk's research is that of phase transitions in lyotropic liquid crystals. Henk, together with Daan Frenkel and Alain Stroobants, realized in the 1980s that a smectic phase in dispersions of rod-like particles can be stable without the presence of attractive interactions, similar to nematic ordering as predicted earlier by Onsager [3]. Together with Gert-Jan Vroege he wrote a seminal review in this area [4]. Henk once said that 'one can only truly develop one colloidal model system in one's career' and in his case this must be that of gibbsite platelets. Initially Henk's group pursued another polymorph of aluminium hydroxide, boehmite, which forms rod-like particles [5], which already displayed nematic liquid crystal phases. The real breakthrough came when the same precursors treated the produced gibbsite platelets slightly differently. These reliably form a discotic nematic phase [6] and, despite the polydispersity in their diameter, a columnar phase [7]. A theme encompassing a wide range of soft matter systems is that of colloidal dynamics and phase transition kinetics. Many colloidal systems have a tendency to get stuck in metastable states, such as gels or glasses. This is a nuisance if one wishes to study phase transitions, but it is of great practical significance. Such issues feature in many of Henk's publications, and with Valerie Anderson he wrote a highly cited review in this area [8]. Henk Lekkerkerker has also invested significant effort into the promotion of synchrotron radiation studies of colloidal suspensions. He was one of the great supporters of the Dutch-Belgian beamline 'DUBBLE' project at the ESRF [9]. He attended one of the very first experiments in Grenoble in 1999, which led to a Nature publication [7]. He was strongly involved in many other experiments which followed and also has been a

Experimental and Numerical Investigations on Colloid-facilitated Plutonium Reactive Transport in Fractured Tuffaceous Rocks

Science.gov (United States)

Dai, Z.; Wolfsberg, A. V.; Zhu, L.; Reimus, P. W.

2017-12-01

Colloids have the potential to enhance mobility of strongly sorbing radionuclide contaminants in fractured rocks at underground nuclear test sites. This study presents an experimental and numerical investigation of colloid-facilitated plutonium reactive transport in fractured porous media for identifying plutonium sorption/filtration processes. The transport parameters for dispersion, diffusion, sorption, and filtration are estimated with inverse modeling for minimizing the least squares objective function of multicomponent concentration data from multiple transport experiments with the Shuffled Complex Evolution Metropolis (SCEM). Capitalizing on an unplanned experimental artifact that led to colloid formation and migration, we adopt a stepwise strategy to first interpret the data from each experiment separately and then to incorporate multiple experiments simultaneously to identify a suite of plutonium-colloid transport processes. Nonequilibrium or kinetic attachment and detachment of plutonium-colloid in fractures was clearly demonstrated and captured in the inverted modeling parameters along with estimates of the source plutonium fraction that formed plutonium-colloids. The results from this study provide valuable insights for understanding the transport mechanisms and environmental impacts of plutonium in fractured formations and groundwater aquifers.

Mobilization And Characterization Of Colloids Generated From Cement Leachates Moving Through A SRS Sandy Sediment

International Nuclear Information System (INIS)

Li, D.; Roberts, K.; Kaplan, D.; Seaman, J.

2011-01-01

Naturally occurring mobile colloids are ubiquitous and are involved in many important processes in the subsurface zone. For example, colloid generation and subsequent mobilization represent a possible mechanism for the transport of contaminants including radionuclides in the subsurface environments. For colloid-facilitated transport to be significant, three criteria must be met: (1) colloids must be generated; (2) contaminants must associate with the colloids preferentially to the immobile solid phase (aquifer); and (3) colloids must be transported through the groundwater or in subsurface environments - once these colloids start moving they become 'mobile colloids'. Although some experimental investigations of particle release in natural porous media have been conducted, the detailed mechanisms of release and re-deposition of colloidal particles within natural porous media are poorly understood. Even though this vector of transport is known, the extent of its importance is not known yet. Colloid-facilitated transport of trace radionuclides has been observed in the field, thus demonstrating a possible radiological risk associated with the colloids. The objective of this study was to determine if cementitious leachate would promote the in situ mobilization of natural colloidal particles from a SRS sandy sediment. The intent was to determine whether cementitious surface or subsurface structure would create plumes that could produce conditions conducive to sediment dispersion and mobile colloid generation. Column studies were conducted and the cation chemistries of influents and effluents were analyzed by ICP-OES, while the mobilized colloids were characterized using XRD, SEM, EDX, PSD and Zeta potential. The mobilization mechanisms of colloids in a SRS sandy sediment by cement leachates were studied.

The immunopathogenesis of celiac disease reveals possible therapies beyond the gluten-free diet.

Science.gov (United States)

McAllister, Christopher S; Kagnoff, Martin F

2012-07-01

Celiac disease is a T cell-mediated autoimmune inflammatory disease of the small intestine that is activated by gluten. The diagnosis of celiac disease is challenging as patients display a wide range of symptoms and some are asymptomatic. A lifelong gluten-free diet is the only currently approved treatment of celiac disease. Although the diet is safe and effective, the compliance rates and patient acceptance vary. Furthermore, many patients treated with a gluten-free diet continue to be mildly to severely symptomatic with persistent histological abnormalities, and a small number of patients develop refractory celiac disease. New therapeutic adjuncts and potential alternatives to the gluten-free diet could improve the treatment options for these patients. Advances in understanding the immunopathogenesis of celiac disease have suggested several types of therapeutic strategies that may augment or supplant the gluten-free diet. Some of these strategies attempt to decrease the immunogenicity of gluten-containing grains by manipulating the grain itself or by using oral enzymes to break down immunogenic peptides that normally remain intact during digestion. Other strategies focus on preventing the absorption of these peptides, preventing tissue transglutaminase from rendering gluten peptides more immunogenic, or inhibiting their binding to celiac disease-specific antigen-presenting molecules. Strategies that limit T cell migration to the small intestine or that reestablish mucosal homeostasis and tolerance to gluten antigens are also being explored. Additionally, it is vital to develop new therapeutic options for refractory celiac disease patients. This review highlights therapeutic strategies that may ultimately improve the health and well-being of individuals with celiac disease.

Dispersions of silica nanoparticles in ionic liquids investigated with advanced rheology

International Nuclear Information System (INIS)

Wittmar, Alexandra; Ruiz-Abad, David; Ulbricht, Mathias

2012-01-01

The colloidal stabilities of dispersions of unmodified and surface-functionalized SiO 2 nanoparticles in hydrophobic and hydrophilic imidazolium-based ionic liquids were studied with advanced rheology at three temperatures (25, 100, and 200 °C). The rheological behavior of the dispersions was strongly affected by the ionic liquids hydrophilicity, by the nanoparticles surface, by the concentration of the nanoparticles in the dispersion as well as by the temperature. The unmodified hydrophilic nanoparticles showed a better compatibility with the hydrophilic ionic liquid. The SiO 2 surface functionalization with hydrophobic groups clearly improved the colloidal stability of the dispersions in the hydrophobic ionic liquid. The temperature increase was found to lead to a destabilization in all studied systems, especially at higher concentrations. The results of this study imply that ionic liquids with tailored properties could be used in absorbers directly after reactors for gas-phase synthesis of nanoparticles or/and as solvents for their further surface functionalization without agglomeration or aggregation.

IPR CATUARA TM – new cultivar of high gluten wheat

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Carlos Roberto Riede

2015-03-01

Full Text Available The wheat cultivar IPR Catuara TM, obtained from a cross between the line LD 975 and the cultivar IPR 85, exhibits high gluten strength, which will allow the milling industry to supplement flours from wheats with weaker gluten strength, resulting in better quality products for the final consumer.

Reductive and oxidative reactions with inorganic colloids in aqueous solution initiated by ultrasound

International Nuclear Information System (INIS)

Mulvaney, P.C.; Sostaric, J.Z.; Ashokkumar, M.; Grieser, F.

1998-01-01

Full text: The absorption of ultrasound in an aqueous solution can lead to the formation of H and OH radicals which can act as redox species or react with solutes to produce secondary radicals which themselves may participate in electron transfer reactions. The radical formation occurs through the growth then rapid collapse of microbubbles a process that produces localised hot spots with an internal temperature of the order of 5000 K. We have examined two colloidal systems one involving the reductive dissolution of MnO 2 colloids and the other the oxidative dissolution of CdS colloids. In the case of MnO 2 dissolution we found that the reduction of the colloidal metal oxide was considerably enhanced in the presence of aliphatic alcohols in solution and the longer the alkyl chain length on the alcohol the greater its effect. The dissolution of CdS colloids which we ascribe to the reaction of H 2 O 2 and O 2 - with the metal sulfide lo yield Cd 2+ and S could be significantly retarded by the presence of excess S 2- in solution. The mechanisms involved in these two dissolution processes will he presented. Our results clearly show that sonochemical reactions are quite efficient in colloidal solutions and this fact needs to be considered when using sonication to disperse colloidal material in solution, a common practice among colloid chemists

Colloid-facilitated radionuclide transport: a regulatory perspective

Science.gov (United States)

Dam, W. L.; Pickett, D. A.; Codell, R. B.; Nicholson, T. J.

2001-12-01

What hydrogeologic-geochemical-microbial conditions and processes affect migration of radionuclides sorbed onto microparticles or native colloid-sized radionuclide particles? The U.S. Nuclear Regulatory Commission (NRC) is responsible for protecting public health, safety, and the environment at numerous nuclear facilities including a potential high-level nuclear waste disposal site. To fulfill these obligations, NRC needs to understand the mechanisms controlling radionuclide release and transport and their importance to performance. The current focus of NRC staff reviews and technical interactions dealing with colloid-facilitated transport relates to the potential nuclear-waste repository at Yucca Mountain, Nevada. NRC staff performed bounding calculations to quantify radionuclide releases available for ground-water transport to potential receptors from a Yucca Mountain repository. Preliminary analyses suggest insignificant doses of plutonium and americium colloids could be derived from spent nuclear fuel. Using surface complexation models, NRC staff found that colloids can potentially lower actinide retardation factors by up to several orders of magnitude. Performance assessment calculations, in which colloidal transport of plutonium and americium was simulated by assuming no sorption or matrix diffusion, indicated no effect of colloids on human dose within the 10,000 year compliance period due largely to long waste-package lifetimes. NRC staff have identified information gaps and developed technical agreements with the U.S. Department of Energy (DOE) to ensure sufficient information will be presented in any potential future Yucca Mountain license application. DOE has agreed to identify which radionuclides could be transported via colloids, incorporate uncertainties in colloid formation, release and transport parameters, and conceptual models, and address the applicability of field data using synthetic microspheres as colloid analogs. NRC is currently

SANS observations on weakly flocculated dispersions

DEFF Research Database (Denmark)

Mischenko, N.; Ourieva, G.; Mortensen, K.

1997-01-01

Structural changes occurring in colloidal dispersions of poly-(methyl metacrylate) (PMMA) particles, sterically stabilized with poly-(12-hydroxystearic acid) (PHSA), while varying the solvent quality, temperature and shear rate, are investigated by small-angle neutron scattering (SANS......). For a moderately concentrated dispersion in a marginal solvent the transition on cooling from the effective stability to a weak attraction is monitored, The degree of attraction is determined in the framework of the sticky spheres model (SSM), SANS and rheological results are correlated....

Long-term kinetic effects and colloid formations in dissolution of LWR spent fuels

Energy Technology Data Exchange (ETDEWEB)

Ahn, T.M.

1996-11-01

This report evaluates continuous dissolution and colloid formation during spent-fuel performance under repository conditions in high-level waste disposal. Various observations suggest that reprecipitated layers formed on spent-fuel surfaces may not be protective. This situation may lead to continuous dissolution of highly soluble radionuclides such as C-14, Cl-36, Tc-99, I-129, and Cs-135. However, the diffusion limits of various species involved may retard dissolution significantly. For low-solubility actinides such as Pu-(239+240) or Am-(241+243), various processes regarding colloid formation have been analyzed. The processes analyzed are condensation, dispersion, and sorption. Colloid formation may lead to significant releases of low-solubility actinides. However, because there are only limited data available on matrix dissolution, colloid formation, and solubility limits, many uncertainties still exist. These uncertainties must be addressed before the significance of radionuclide releases can be determined. 118 refs.

Long-term kinetic effects and colloid formations in dissolution of LWR spent fuels

International Nuclear Information System (INIS)

Ahn, T.M.

1996-11-01

This report evaluates continuous dissolution and colloid formation during spent-fuel performance under repository conditions in high-level waste disposal. Various observations suggest that reprecipitated layers formed on spent-fuel surfaces may not be protective. This situation may lead to continuous dissolution of highly soluble radionuclides such as C-14, Cl-36, Tc-99, I-129, and Cs-135. However, the diffusion limits of various species involved may retard dissolution significantly. For low-solubility actinides such as Pu-(239+240) or Am-(241+243), various processes regarding colloid formation have been analyzed. The processes analyzed are condensation, dispersion, and sorption. Colloid formation may lead to significant releases of low-solubility actinides. However, because there are only limited data available on matrix dissolution, colloid formation, and solubility limits, many uncertainties still exist. These uncertainties must be addressed before the significance of radionuclide releases can be determined. 118 refs

Better resolved low frequency dispersions by the apt use of Kramers-Kronig relations, differential operators and all-in-1 modelling

Directory of Open Access Journals (Sweden)

Jan van Turnhout

2016-05-01

Full Text Available The dielectric spectra of colloidal systems often contain a typical low frequency dispersion, which usually remains unnoticed, because of the presence of strong conduction losses. The KK relations offer a means for converting  into  data. This allows us to calculate conduction free  spectra in which the l.f. dispersion will show up undisturbed. This interconversion can be done on line with a moving frame of logarithmically spaced  data. The coefficients of the conversion frames were obtained by kernel matching and by using symbolic differential operators. Logarithmic derivatives and differences of  and  provide another option for conduction free data analysis. These difference-based functions actually derived from approximations to the distribution function, have the additional advantage of improving the resolution power of dielectric studies. A high resolution is important because of the rich relaxation structure of colloidal suspensions. The development of all-in-1 modelling facilitates the conduction free and high resolution data analysis. This mathematical tool allows the apart-together fitting of multiple data and multiple model functions. It proved also useful to go around the KK conversion altogether. This was achieved by the combined approximating  and  data with a complex rational fractional power function. The all-in-1 minimization turned out to be also highly useful for the dielectric modelling of a suspension with the complex dipolar coefficient. It guarantees a secure correction for the electrode polarization, so that the modelling with the help of the differences  and  can zoom in on the genuine colloidal relaxations.

Colloidal Quantum Dot Photovoltaics: A Path Forward

KAUST Repository

Kramer, Illan J.; Sargent, Edward H.

2011-01-01

spectrum. CQD materials' ease of processing derives from their synthesis, storage, and processing in solution. Rapid advances have brought colloidal quantum dot photovoltaic solar power conversion efficiencies of 6% in the latest reports. These achievements

Gluten-degrading bacteria are present in the human small intestine of healthy volunteers and celiac patients.

Science.gov (United States)

Herrán, Alexandra R; Pérez-Andrés, Jénifer; Caminero, Alberto; Nistal, Esther; Vivas, Santiago; Ruiz de Morales, José María; Casqueiro, Javier

2017-09-01

Gluten is the only known environmental factor that triggers celiac disease. Several studies have described an imbalance between the intestinal microbiota of different individuals based on diagnoses. Moreover, recent studies have suggested that human bacteria may play an important role in gluten hydrolysis. However, there has been no research focusing on the small intestine. This study aimed to characterize the adult small intestine microbiota possibly implicated in gluten hydrolysis. Duodenal biopsies from different diagnosed individuals were cultured in a gluten-containing medium, and the grown microbiota was analyzed by culture dependent/independent methods. Results showed that gluten-degrading bacteria can be found in the human small intestine. Indeed, 114 bacterial strains belonging to 32 species were isolated; 85 strains were able to grow in a medium containing gluten as the sole nitrogen source, 31 strains showed extracellular proteolytic activity against gluten protein and 27 strains showed peptidolytic activity towards the 33 mer peptide, an immunogenic peptide for celiac disease patients. We found that there are no differences based on the diagnosis, but each individual has its own population of gluten-hydrolyzing bacteria. These bacteria or their gluten-degrading enzymes could help to improve the quality of life of celiac disease patients'. Copyright © 2017 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.

The everyday life of adolescent coeliacs: issues of importance for compliance with the gluten-free diet.

Science.gov (United States)

Olsson, C; Hörnell, A; Ivarsson, A; Sydner, Y M

2008-08-01

Noncompliance with the gluten-free diet is often reported among adolescents with coeliac disease. However, knowledge is limited regarding their own perspectives and experiences of managing the disease and the prescription of a gluten-free diet. The aim of this study was to explore how adolescents with coeliac disease perceive and manage their everyday lives in relation to a gluten-free diet. In total, 47 adolescents with coeliac disease, divided into 10 focus groups, were interviewed. In the qualitative analysis, themes emerged to illustrate and explain the adolescents' own perspectives on life with a gluten-free diet. The probability of compliance with the gluten-free diet was comprised by insufficient knowledge of significant others, problems with the availability and sensory acceptance of gluten-free food, insufficient social support and their perceived dietary deviance. Three different approaches to the gluten-free diet emerged: compliers, occasional noncompliers, and noncompliers. Each approach, as a coping strategy, was rational in the sense that it represented the adolescents' differing views of everyday life with coeliac disease and a prescription of a gluten-free diet. dolescents with coeliac disease experience various dilemmas related to the gluten-free diet. The study demonstrated unmet needs and implies empowerment strategies for optimum clinical outcomes.

Maize Prolamins Could Induce a Gluten-Like Cellular Immune Response in Some Celiac Disease Patients

Science.gov (United States)

Ortiz-Sánchez, Juan P.; Cabrera-Chávez, Francisco; Calderón de la Barca, Ana M.

2013-01-01

Celiac disease (CD) is an autoimmune-mediated enteropathy triggered by dietary gluten in genetically prone individuals. The current treatment for CD is a strict lifelong gluten-free diet. However, in some CD patients following a strict gluten-free diet, the symptoms do not remit. These cases may be refractory CD or due to gluten contamination; however, the lack of response could be related to other dietary ingredients, such as maize, which is one of the most common alternatives to wheat used in the gluten-free diet. In some CD patients, as a rare event, peptides from maize prolamins could induce a celiac-like immune response by similar or alternative pathogenic mechanisms to those used by wheat gluten peptides. This is supported by several shared features between wheat and maize prolamins and by some experimental results. Given that gluten peptides induce an immune response of the intestinal mucosa both in vivo and in vitro, peptides from maize prolamins could also be tested to determine whether they also induce a cellular immune response. Hypothetically, maize prolamins could be harmful for a very limited subgroup of CD patients, especially those that are non-responsive, and if it is confirmed, they should follow, in addition to a gluten-free, a maize-free diet. PMID:24152750

Effect of storage time and temperature on the rheological and microstructural properties of gluten

NARCIS (Netherlands)

Nicolas, Y.; Smit, R.J.M.; van Aalst, H.; Esselink, F.J.; Weegels, P.L.; Agterof, W.G.M.

2003-01-01

To investigate the effects of frozen storage on the rheological and microstructural properties of gluten, two model systems were investigated: System A, gluten and water; System B, gluten, water, and NaCl. The storage time was varied from 1 to 16 weeks and the storage temperature was varied from -5

Conducting polymer colloids, hydrogels, and cryogels: common start to various destinations

Czech Academy of Sciences Publication Activity Database

Stejskal, Jaroslav; Bober, Patrycja

2018-01-01

Roč. 296, č. 5 (2018), s. 989-994 ISSN 0303-402X R&D Projects: GA ČR(CZ) GA16-02787S Institutional support: RVO:61389013 Keywords : conducting polymer * polyaniline * colloidal dispersion Subject RIV: CD - Macromolecular Chemistry OBOR OECD: Polymer science Impact factor: 1.723, year: 2016

IMAGE ANALYSIS OF BREAD CRUMB STRUCTURE IN RELATION TO GLUTEN STRENGTH OF WHEAT

Directory of Open Access Journals (Sweden)

D. Magdić

2006-06-01

Full Text Available The objective of this study was to determine bread slice medium part properties in relation to quality parameters with a focus on gluten strength. Since sensory evaluation of bread is time consuming, expensive and subjective in nature, computerized image analysis was applied as objective method of bread crumb quality evaluation. Gluten Index method was applied as fast and reliable tool for defining gluten strength of wheat. Significant (P90 Ana, Demetra, Klara, Srpanjka and Divana have shown trend to give unequal and bigger crumb grains while cultivars Golubica, Barbara, Žitarka, Kata and Sana with optimal gluten strength (GI= 60-90 have shown finer and uniform crumb grain.

Motives for adherence to a gluten-free diet: a qualitative investigation involving adults with coeliac disease.

Science.gov (United States)

Dowd, A J; Tamminen, K A; Jung, M E; Case, S; McEwan, D; Beauchamp, M R

2014-12-01

Currently , the only treatment for coeliac disease is life long adherence to a strict gluten-free diet. Strict adherence to a gluten-free diet is challenging, with recent reports suggesting that adherence rates range from 42% to 91%. The present study aimed to: (i) identify motives for adhering to a gluten-free diet and (ii) explore factors implicated in adherence and non-adherence behaviour in terms of accidental and purposeful gluten consumption among adults with coeliac disease. Two hundred and three adults with coeliac disease completed an online questionnaire. Using a qualitative design, relationships were examined between reported adherence and motivation to follow a gluten-free diet, as well as the onset, duration and severity of symptoms. Feelings of desperation (‘hitting rock bottom’) and needing to gain or lose weight were associated with the strictest adherence to a gluten-free diet. Participants who accidentally consumed gluten over the past week developed symptoms the most quickly and reported the most pain over the past 6 months. Participants who consumed gluten on purpose over the past week reported a shorter duration of symptoms and less pain over the past 6 months. Hitting rock bottom and needing to gain or lose weight were factors associated with the strictest adherence, when considered in the context of both accidental and purposeful gluten consumption. Future research is warranted to develop resources to help people with coeliac disease follow a strict gluten-free diet.

Balancing consumer protection and scientific integrity in the face of uncertainty: the example of gluten-free foods.

Science.gov (United States)

McCabe, Margaret Sova

2010-01-01

In 2009, gluten-free foods were not only "hot" in the marketplace, several countries, including the United States, continued efforts to define gluten-free and appropriate labeling parameters. The regulatory process illuminates how difficult regulations based on safe scientific thresholds can be for regulators, manufacturers and consumers. This article analyzes the gluten-free regulatory landscape, challenges to defining a safe gluten threshold, and how consumers might need more label information beyond the term "gluten-free." The article includes an overview of international gluten-free regulations, the Food and Drug Administration (FDA) rulemaking process, and issues for consumers.

Double-Blind Randomized Clinical Trial: Gluten versus Placebo Rechallenge in Patients with Lymphocytic Enteritis and Suspected Celiac Disease.

Directory of Open Access Journals (Sweden)

Mercè Rosinach

Full Text Available The role of gluten as a trigger of symptoms in non-coeliac gluten sensitivity has been questioned.To demonstrate that gluten is the trigger of symptoms in a subgroup of patients fulfilling the diagnostic criteria for non-coeliac gluten sensitivity (NCGS, which presented with lymphocytic enteritis, positive celiac genetics and negative celiac serology.Double-blind randomized clinical trial of gluten vs placebo rechallenge.>18 years of age, HLA-DQ2/8+, negative coeliac serology and gluten-dependent lymphocytic enteritis, and GI symptoms, with clinical and histological remission at inclusion. Eighteen patients were randomised: 11 gluten (20 g/day and 7 placebo. Clinical symptoms, quality of life (GIQLI, and presence of gamma/delta+ cells and transglutaminase deposits were evaluated.91% of patients had clinical relapse during gluten challenge versus 28.5% after placebo (p = 0.01. Clinical scores and GIQLI worsened after gluten but not after placebo (p<0.01. The presence of coeliac tissue markers at baseline biopsy on a gluten-free diet allowed classifying 9 out of the 18 (50% patients as having probable 'coeliac lite' disease.This proof-of-concept study indicates that gluten is the trigger of symptoms in a subgroup of patients fulfilling the diagnostic criteria for NCGS. They were characterized by positive celiac genetics, lymphocytic enteritis, and clinical and histological remission after a gluten-free diet.ClinicalTrials.gov NCT02472704.

Generation of colloidal granules and capsules from double emulsion drops

Science.gov (United States)

Hess, Kathryn S.

Assemblies of colloidal particles are extensively used in ceramic processing, pharmaceuticals, inks and coatings. In this project, the aim was to develop a new technique to fabricate monodispersed colloidal assemblies. The use of microfluidic devices and emulsion processing allows for the fabrication of complex materials that can be used in a variety of applications. A microfluidic device is used to create monodispersed water/oil/water (w/o/w) double emulsions with interior droplets of colloidal silica suspension ranging in size from tens to hundreds of microns. By tailoring the osmotic pressure using glycerol as a solute in the continuous and inner phases of the emulsion, we can control the final volume size of the monodispersed silica colloidal crystals that form in the inner droplets of the double emulsion. Modifying the ionic strength in the colloidal dispersion can be used to affect the particle-particle interactions and crystal formation of the final colloidal particle. This w/o/w technique has been used with other systems of metal oxide colloids and cellulose nanocrystals. Encapsulation of the colloidal suspension in a polymer shell for the generation of ceramic-polymer core-shell particles has also been developed. These core-shell particles have spawned new research in the field of locally resonant acoustic metamaterials. Systems and chemistries for creating cellulose hydrogels within the double emulsions have also been researched. Water in oil single emulsions and double emulsions have been used to create cellulose hydrogel spheres in the sub-100 micron diameter range. Oil/water/oil double emulsions allow us to create stable cellulose capsules. The addition of a second hydrogel polymer, such as acrylate or alginate, further strengthens the cellulose gel network and can also be processed into capsules and particles using the microfluidic device. This work could have promising applications in acoustic metamaterials, personal care products, pharmaceuticals

The Celiac Patient Antibody Response to Conventional and Gluten-Removed Beer.

Science.gov (United States)

Allred, Laura K; Lesko, Katherine; McKiernan, Diane; Kupper, Cynthia; Guandalini, Stefano

2017-03-01

Enzymatic digestion, or hydrolysis, has been proposed for treating gluten-containing foods and beverages to make them safe for persons with celiac disease (CD). There are no validated testing methods that allow the quantitation of all the hydrolyzed or fermented gluten peptides in foods and beverages that might be harmful to CD patients, making it difficult to assess the safety of hydrolyzed products. This study examines an ELISA-based method to determine whether serum antibody binding of residual peptides in a fermented barley-based product is greater among active-CD patients than a normal control group, using commercial beers as a test case. Sera from 31 active-CD patients and 29 nonceliac control subjects were used to assess the binding of proteins from barley, rice, traditional beer, gluten-free beer, and enzymatically treated (gluten-removed) traditional beer. In the ELISA, none of the subjects' sera bound to proteins in the gluten-free beer. Eleven active-CD patient serum samples demonstrated immunoglobulin A (IgA) or immunoglobulin G (IgG) binding to a barley extract, compared to only one nonceliac control subject. Of the seven active-CD patients who had an IgA binding response to barley, four also responded to traditional beer, and two of these responded to the gluten-removed beer. None of the nonceliac control subjects' sera bound to all three beer samples. Binding of protein fragments in hydrolyzed or fermented foods and beverages by serum from active-CD patients, but not nonceliac control subjects, may indicate the presence of residual peptides that are celiac-specific.

Properties of aqueous dispersion of chitosan and chondroitin sulfate complex derived from aquatic organisms

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Novikov V. Yu.

2016-09-01

Full Text Available Investigation of production of chondroitin sulfate, chitosan and polyelectrolyte complexes based on them received from the local marine raw materials is relevant from the point of view of developing a comprehensive waste-free technology for natural raw materials processing. The objects of study are chitosan derived from the shell of the Kamchatka crab Paralithodes camtschaticus and chondroitin sulfate derived from cartilage of salmon Salmon salar. To determine the surface tension of polyelectrolyte complex solutions and dispersions the Wilhelmy method has been used, the effective radius of particle dispersion has been calculated by light scattering, measurements of effective viscosity have been carried out under shear deformation. The conditions of formation, surface and rheological properties of the chitosan and chondroitin sulfate complex extracted from aquatic organisms in the Barents Sea have been studied. Obtaining conditions and molar ratios of these polyelectrolytes in which the aqueous dispersion of the complex remains stable for a long time have been established. It has been found that by addition of chondroitin sulfate solution to chitosan solution in molar ratios of 1 : 3; 1 : 6 the dispersion of the polyelectrolyte complex stable for 2 to 3 days has been formed. The polyelectrolyte complex dispersions behave as non-Newtonian pseudoplastic liquid. When the molar ratio of the mixed solution is 1 : 1 (regardless of the sequence of mixing suspension of the polyelectrolyte complex has been formed, then there is precipitation. Equilibrium surface tension of the aqueous dispersion of the polyelectrolyte complex is higher than that of solutions of chondroitin sulfate and chitosan. The effective radius of particles in the complex dispersion has been determined. The effective radius of the particles in the complex dispersion depends on the molar ratio of chondroitin sulfate : chitosan. A qualitative scheme of formation of polyelectrolyte

Modification of wheat gluten with citric acid to produce superabsorbent materials

Science.gov (United States)

Wheat gluten was reacted with citric acid to produce natural superabsorbent materials able to absorb up to 78 times its weight in water. The properties of the modified gluten samples were characterized using Fourier Transform Infra-red (FTIR) spectroscopy, thermogravimetric analysis, and water uptak...

Non-equilibrium relaxation and near-arrest dynamics in colloidal suspensions

International Nuclear Information System (INIS)

Medina-Noyola, M; RamIrez-Gonzalez, Pedro

2009-01-01

In this work we propose a theory to describe the irreversible diffusive relaxation of the local concentration of a colloidal dispersion that proceeds toward its stable thermodynamic equilibrium state, but which may in the process be trapped in metastable or dynamically arrested states. The central assumption of this theory is that the irreversible relaxation of the macroscopically observed mean value n-bar(r,t) of the local concentration of colloidal particles is described by a diffusion equation involving a local mobility b*(r,t) that depends not only on the mean value n-bar(r,t) but also on the covariance σ(r,r';t)≡δn(r,t)δn(r',t)-bar of the fluctuations δn(r,t)≡n(r,t)-n-bar(r,t). This diffusion equation must hence be solved simultaneously with the relaxation equation for the covariance σ(r,r';t), and here we also derive the corresponding relaxation equation. The dependence of the local mobility b*(r,t) on the mean value and the covariance is determined by a self-consistent set of equations involving now the spatially and temporally non-local time-dependent correlation functions, which in a uniform system in equilibrium reduces to the self-consistent generalized Langevin equation (SCGLE) theory of colloid dynamics. The resulting general theory considers the possibility that these relaxation processes occur under the influence of external fields, such as gravitational forces acting in the process of sedimentation. In this paper, however, we describe a simpler application, in which the system remains spatially uniform during the irreversible relaxation process, and discuss the general features of the glass transition scenario predicted by this non-equilibrium theory.

Prevalence and Characterization of Self-Reported Gluten Sensitivity in The Netherlands

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Tom van Gils

2016-11-01

Full Text Available Background: A growing number of individuals reports symptoms related to the ingestion of gluten-containing food in the absence of celiac disease. Yet the actual prevalence is not well established. Methods: Between April 2015 and March 2016, unselected adults visiting marketplaces, dental practices and a university in The Netherlands were asked to complete a modified validated questionnaire for self-reported gluten sensitivity (srGS. Results: Among the 785 adults enquired, two had celiac disease. Forty-nine (6.2% reported symptoms related to the ingestion of gluten-containing food. These individuals were younger, predominantly female and lived more frequently in urban regions compared with the other respondents. Symptoms reported included bloating (74%, abdominal discomfort (49% and flatulence (47%. A total of 23 (47% srGS individuals reported having had tried a gluten-free or gluten-restricted diet. Abdominal discomfort related to fermentable oligosaccharide, disaccharide, monosaccharide and polyol (FODMAP-containing food was more often reported in srGS individuals compared with the other respondents (73.5% vs. 21.7%, p < 0.001. Conclusion: Self-reported GS is common in The Netherlands, especially in younger individuals, females and urban regions, although the prevalence was lower than in a comparable recent UK study. It cannot be excluded that FODMAPs are in part responsible for these symptoms.

Effects of Hofmeister salt series on gluten network formation: Part I. Cation series.

Science.gov (United States)

Tuhumury, H C D; Small, D M; Day, L

2016-12-01

Different cationic salts were used to investigate the effects of the Hofmeister salt series on gluten network formation. The effects of cationic salts on wheat flour dough mixing properties, the rheological and the chemical properties of the gluten extracted from the dough with different respective salts, were investigated. The specific influence of different cationic salts on the gluten structure formation during dough mixing, compared to the sodium ion, were determined. The effects of different cations on dough and gluten of different flours mostly followed the Hofmeister series (NH4(+), K(+), Na(+), Mg(2+) and Ca(2+)). The impacts of cations on gluten structure and dough rheology at levels tested were relatively small. Therefore, the replacement of sodium from a technological standpoint is possible, particularly by monovalent cations such as NH4(+), or K(+). However the levels of replacement need to take into account sensory attributes of the cationic salts. Copyright © 2016 Elsevier Ltd. All rights reserved.

Living gluten-free: adherence, knowledge, lifestyle adaptations and feelings towards a gluten-free diet.

Science.gov (United States)

Silvester, J A; Weiten, D; Graff, L A; Walker, J R; Duerksen, D R

2016-06-01

A gluten-free diet (GFD) requires tremendous dedication, involving substantive changes to diet and lifestyle that may have a significant impact upon quality of life. The present study aimed io assess dietary adherence, knowledge of a GFD, and the emotional and lifestyle impact of a GFD. Community dwelling adults following a GFD completed a questionnaire with items related to reasons for avoiding gluten, diagnostic testing, GFD adherence, knowledge and sources of information about a GFD, the Work and Social Adjustment Scale, and the effect of a GFD diet on lifestyle, feelings and behaviours. Strict GFD adherence among the 222 coeliac disease (CD) patients was 56%. Non-CD individuals (n = 38) were more likely to intentionally ingest gluten (odds ratio = 3.7; 95% confidence interval = 1.4-9.4). The adverse impact of a GFD was modest but most pronounced in the social domain. Eating shifted from the public to the domestic sphere and there were feelings of social isolation. Affective responses reflected resilience because acceptance and relief were experienced more commonly than anxiety or anger. Non-CD respondents were less knowledgeable and less likely to consult health professionals. They experienced less anger and depression and greater pleasure in eating than CD respondents. The findings obtained in the present suggest there is good potential for positive adaptation to the demands of a GFD; nevertheless, there is a measurable degree of social impairment that merits further study. The GFD may be a viable treatment option for conditions other than CD; however, education strategies regarding the need for diagnostic testing to exclude CD are required. © 2015 The British Dietetic Association Ltd.

Adsorbed States of phosphonate derivatives of N-heterocyclic aromatic compounds, imidazole, thiazole, and pyridine on colloidal silver: comparison with a silver electrode.

Science.gov (United States)

Podstawka, Edyta; Olszewski, Tomasz K; Boduszek, Bogdan; Proniewicz, Leonard M

2009-09-03

Here, we report a systematic surface-enhanced Raman spectroscopy (SERS) study of the structures of phosphonate derivatives of the N-heterocyclic aromatic compounds imidazole (ImMeP ([hydroxy(1H-imidazol-5-yl)methyl]phosphonic acid) and (ImMe)(2)P (bis[hydroxy-(1H-imidazol-4-yl)-methyl]phosphinic acid)), thiazole (BAThMeP (butylaminothiazol-2-yl-methyl)phosphonic acid) and BzAThMeP (benzylaminothiazol-2-yl-methyl)phosphonic acid)), and pyridine ((PyMe)(2)P (bis[(hydroxypyridin-3-yl-methyl)]phosphinic acid)) adsorbed on nanometer-sized colloidal particles. We compared these structures to those on a roughened silver electrode surface to determine the relationship between the adsorption strength and the geometry. For example, we showed that all of these biomolecules interact with the colloidal surface through aromatic rings. However, for BzAThMeP, a preferential interaction between the benzene ring and the colloidal silver surface is observed more so than that between the thiazole ring and this substrate. The PC(OH)C fragment does not take part in the adsorption process, and the phosphonate moiety of ImMeP and (ImMe)(2)P, being removed from the surface, only assists in this process.

Colloid Release From Differently Managed Loess Soil

DEFF Research Database (Denmark)

Vendelboe, Anders Lindblad; Schjønning, Per; Møldrup, Per

2012-01-01

The content of water-dispersible colloids (WDC) in a soil can have a major impact on soil functions, such as permeability to water and air, and on soil strength, which can impair soil fertility and workability. In addition, the content of WDC in the soil may increase the risk of nutrient loss...... and of colloid-facilitated transport of strongly sorbing compounds. In the present study, soils from the Bad Lauchsta¨dt longterm static fertilizer experiment with different management histories were investigated to relate basic soil properties to the content of WDC, the content of water-stable aggregates (WSA......), and aggregate tensile strength. Our studies were carried out on soils on identical parent material under controlled management conditions, enabling us to study the long-term effects on soil physical properties with few explanatory variables in play. The content of WDC and the amount of WSA were measured...

Recent developments in gluten-free bread baking approaches: a review

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Kun WANG

Full Text Available Abstract Celiac disease (CD is one of the most common human intestinal malabsorption diseases. The only effective treatment for patients with CD is to follow a gluten-free (GF diet strictly. Nowadays, the increasing incidence of CD promotes worldwide interests for various desirable GF products. However, baking without gluten, the key ingredient for bread structure and quality, is a big challenge for all bakers and cereal researchers. Several approaches have been applied to understand and improve gluten-free bread (GFB elaboration and further studies are still required. The main focus of this review is to discuss the approaches for GFB improvements in recent 5 years, including the use of novel alternative flours, functional ingredients, processing aids, additives, innovative techniques, and their combinations.

The Relationship Between Protein Fractions of Wheat Gluten and the Quality of Ring-Shaped Rolls Evaluated by the Echolocation Method

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Grazina Juodeikiene

2005-01-01

Full Text Available This paper presents the results of the relationship between separate protein fractions and the quality of baked ring-shaped rolls. The qualitative and quantitative protein composition of flour derived from some wheat varieties grown in Lithuania has been determined. The protein properties are evaluated by SDS-PAGE. A new method of the analysis of swelling, based on the principle of echolocation, has been used to determine the quality of this specific kind of baked goods. For the application of this method the wheat flour, which is most suitable for the production of ring-shaped rolls, made from the wheat variety Portal (Pasvalys PVRS, has been selected. This flour has the following quality parameters: proteins 10.5 %, gluten 22.0 %, gluten index 47 r.u. Correlation between the flour quality parameters and the quality of the final bread product shows that γ-gliadins (r=–0.63, LMM glutenins (r=0.55, HMM glutenins (r=0.63 and the content of gluten (r=0.87 have the greatest influence on the quality of the ring-shaped rolls.

Prediction of adherence to a gluten-free diet using protection motivation theory among adults with coeliac disease.

Science.gov (United States)

Dowd, A J; Jung, M E; Chen, M Y; Beauchamp, M R

2016-06-01

Coeliac disease is a chronic autoimmune disease that requires strict adherence to a gluten-free diet. However, strict adherence to a gluten-free diet is difficult, with findings from a recent review suggesting that up to 42% of individuals with coeliac disease do not eat a strict gluten-free diet. The present study aimed to examine psychosocial predictors of adherence (purposeful and accidental) to a gluten-free diet among adults with coeliac disease over a 1-month period. In this longitudinal study, 212 North American adults with coeliac disease completed online questionnaires at two time points, baseline and 1 month later. The results revealed that intentions partially mediated the effects of symptom severity, self-regulatory efficacy, planning and knowledge on purposeful gluten consumption. Intentions did not mediate the effects of severity, response cost, self-regulatory efficacy, planning and knowledge for accidental gluten consumption but, interestingly, self-regulatory efficacy directly predicted fewer accidental incidents of gluten-consumption. These findings delineate the differential psychological processes in understanding accidental and purposeful gluten consumption among adults with coeliac disease and emphasise the importance of bolstering self-regulatory efficacy beliefs to prevent accidental and purposeful consumption of gluten. © 2015 The British Dietetic Association Ltd.

Small- bowel mucosal changes and antibody responses after low- and moderate-dose gluten challenge in celiac disease

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Lähdeaho Marja-Leena

2011-11-01

Full Text Available Abstract Background Due to the restrictive nature of a gluten-free diet, celiac patients are looking for alternative therapies. While drug-development programs include gluten challenges, knowledge regarding the duration of gluten challenge and gluten dosage is insufficient. We challenged adult celiac patients with gluten with a view to assessing the amount needed to cause some small-bowel mucosal deterioration. Methods Twenty-five celiac disease adults were challenged with low (1-3 g or moderate (3-5g doses of gluten daily for 12 weeks. Symptoms, small-bowel morphology, densities of CD3+ intraepithelial lymphocytes (IELs and celiac serology were determined. Results Both moderate and low amounts of gluten induced small-bowel morphological damage in 67% of celiac patients. Moderate gluten doses also triggered mucosal inflammation and more gastrointestinal symptoms leading to premature withdrawals in seven cases. In 22% of those who developed significant small- intestinal damage, symptoms remained absent. Celiac antibodies seroconverted in 43% of the patients. Conclusions Low amounts of gluten can also cause significant mucosal deterioration in the majority of the patients. As there are always some celiac disease patients who will not respond within these conditions, sample sizes must be sufficiently large to attain to statistical power in analysis.

Composition of estuarine colloidal material: organic components

Science.gov (United States)

Sigleo, A.C.; Hoering, T.C.; Helz, G.R.

1982-01-01

Colloidal material in the size range 1.2 nm to 0.4 ??m was isolated by ultrafiltration from Chesapeake Bay and Patuxent River waters (U.S.A.). Temperature controlled, stepwise pyrolysis of the freeze-dried material, followed by gas chromatographic-mass spectrometric analyses of the volatile products indicates that the primary organic components of this polymer are carbohydrates and peptides. The major pyrolysis products at the 450??C step are acetic acid, furaldehydes, furoic acid, furanmethanol, diones and lactones characteristic of carbohydrate thermal decomposition. Pyrroles, pyridines, amides and indole (protein derivatives) become more prevalent and dominate the product yield at the 600??C pyrolysis step. Olefins and saturated hydrocarbons, originating from fatty acids, are present only in minor amounts. These results are consistent with the composition of Chesapeake phytoplankton (approximately 50% protein, 30% carbohydrate, 10% lipid and 10% nucleotides by dry weight). The pyrolysis of a cultured phytoplankton and natural particulate samples produced similar oxygen and nitrogencontaining compounds, although the proportions of some components differ relative to the colloidal fraction. There were no lignin derivatives indicative of terrestrial plant detritus in any of these samples. The data suggest that aquatic microorganisms, rather than terrestrial plants, are the dominant source of colloidal organic material in these river and estuarine surface waters. ?? 1982.

Impact of casein and egg white proteins on the structure of wheat gluten-based protein-rich food.

Science.gov (United States)

Wouters, Arno G B; Rombouts, Ine; Lagrain, Bert; Delcour, Jan A

2016-02-01

There is a growing interest in texturally and nutritionally satisfying vegetable alternatives to meat. Wheat gluten proteins have unique functional properties but a poor nutritional value in comparison to animal proteins. This study investigated the potential of egg white and bovine milk casein with well-balanced amino acid composition to increase the quality of wheat gluten-based protein-rich foods. Heating a wheat gluten (51.4 g)-water (100.0 mL) blend for 120 min at 100 °C increased its firmness less than heating a wheat gluten (33.0 g)-freeze-dried egg white (16.8 g)-water (100.0 mL) blend. In contrast, the addition of casein to the gluten-water blend negatively impacted firmness after heating. Firmness was correlated with loss of protein extractability in sodium dodecyl sulfate containing medium during heating, which was higher with egg white than with casein. Even more, heat-induced polymerization of the gluten-water blend with egg white but not with casein was greater than expected from the losses in extractability of gluten and egg white on their own. Structure formation was favored by mixing gluten with egg white but not with casein. These observations were linked to the intrinsic polymerization behavior of egg white and casein, but also to their interaction with gluten. Thus not all nutritionally suitable proteins can be used for enrichment of gluten-based protein-rich foods. © 2015 Society of Chemical Industry.

The effects of nitrogen nutrition and glutenin composition on the gluten quality in wheat genotypes

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NIKOLA HRISTOV

2010-03-01

Full Text Available The effect of nitrogen nutrition treatments on the gluten content and some quality parameters of eight winter wheat cultivars has been studied. Six different nitrogen rates were applied (0, 60, 90, 120, 150 and 180 kg N ha-1 to wheat cultivars chosen according to the structure of their high molecular weight glutenin subunits (HMW-GS at the Glu-D1 locus. Four genotypes with HMW-GS 2 + 12 and another four with HMW-GS 5 + 10 were used in the study. The analysis of gluten quality involved the wet gluten content and rheological properties determined by the sensory and instrumental methods (“Instron 4301”. It was determined that in all the cultivars the wet gluten content increased significantly (P < 0.05 in parallel with N rate increase. The cultivars reacted differently regarding their wet gluten rheological properties. Libellula, a cultivar with poor bread making quality (HMW-GS 2 + 12, did not react to different N rates. Sremica, a cultivar with excellent bread making quality (HMW-GS 5 + 10, reduced its gluten quality as the N rate increased. The values obtained by the instrumental method “Instron 4301” at 90% wet gluten compression varied widely (from 0.002 to 0.041 kN. The increase of N fertilizer rate was significantly positively correlated (r2 = 0.811 with the wet gluten content and strength in the cultivars with HMW-GS 5+10.

Variable selection based near infrared spectroscopy quantitative and qualitative analysis on wheat wet gluten

Science.gov (United States)

Lü, Chengxu; Jiang, Xunpeng; Zhou, Xingfan; Zhang, Yinqiao; Zhang, Naiqian; Wei, Chongfeng; Mao, Wenhua

2017-10-01

Wet gluten is a useful quality indicator for wheat, and short wave near infrared spectroscopy (NIRS) is a high performance technique with the advantage of economic rapid and nondestructive test. To study the feasibility of short wave NIRS analyzing wet gluten directly from wheat seed, 54 representative wheat seed samples were collected and scanned by spectrometer. 8 spectral pretreatment method and genetic algorithm (GA) variable selection method were used to optimize analysis. Both quantitative and qualitative model of wet gluten were built by partial least squares regression and discriminate analysis. For quantitative analysis, normalization is the optimized pretreatment method, 17 wet gluten sensitive variables are selected by GA, and GA model performs a better result than that of all variable model, with R2V=0.88, and RMSEV=1.47. For qualitative analysis, automatic weighted least squares baseline is the optimized pretreatment method, all variable models perform better results than those of GA models. The correct classification rates of 3 class of 30% wet gluten content are 95.45, 84.52, and 90.00%, respectively. The short wave NIRS technique shows potential for both quantitative and qualitative analysis of wet gluten for wheat seed.

Spatial and Temporal Variability in Colloid Dispersion as a Function of Groundwater Injection Rate within Atlantic Coastal Plain Sediments

International Nuclear Information System (INIS)

Seaman, J.C.; P.M. Bertsch and D.I. Kaplan

2007-01-01

A subsurface injection experiment was conducted on the USDOE's Savannah River Site (SRS) to determine the influence of pump-and-treat remediation activities on the generation and transport of groundwater colloids. The impact of colloid generation on formation permeability at injection rates ranging from 19 to 132 L min -1 was monitored using a set of six sampling wells radially spaced at approximate distances of 2.0, 3.0, and 4.5 m from a central injection well. Each sampling well was further divided into three discrete sampling depths that were pumped continuously at a rate of ∼0.1 L min -1 throughout the course of the injection experiment. Discrete samples were collected for turbidity and chemical analysis. Turbidity varied greatly between sampling wells and zones within a given well, ranging from 1 (micro)m) to be readily mobile within the formation. Turbidity measurements taken during this study indicate that colloid mobilization induced by water injection was both spatially and temporally heterogeneous. Furthermore, colloid release did not follow simple predictions based on shear force, presumably due to the complexities encountered in real heterogeneous systems. These findings have important implications to our understanding of how colloids and the co-contaminants are mobilized in the subsurface environment, as well as for the development of monitoring practices that minimize the creation of colloidal artifacts. Technical and logistical obstacles encountered in conducting such an extensive field experiment are also discussed

Anisotropic Model Colloids

NARCIS (Netherlands)

van Kats, C.M.

2008-01-01

The driving forces for fundamental research in colloid science are the ability to manage the material properties of colloids and to unravel the forces that play a role between colloids to be able to control and understand the processes where colloids play an important role. Therefore we are

Characteristics of colloids generated during the corrosion of nuclear waste glasses in groundwater

International Nuclear Information System (INIS)

Feng, X.; Buck, E.C.; Mertz, C.; Bates, J.K.; Cunnane, J.C.; Chaiko, D.

1993-10-01

Aqueous colloidal suspensions were generated by reacting nuclear waste glasses with groundwater at 90 degrees C at different ratios of the glass surface area to solution volume (S/V). The colloids have been characterized in terms of size, charge, identity, and stability with respect to salt concentration, pH, and time, by examination using dynamic light scattering, electrophoretic mobility, and transmission electron microscopy. The colloids are predominately produced by precipitation from solution, possibly with contribution from reacted layers that have spallated from the glass. These colloids are silicon-rich minerals. The colloidal suspensions agglomerate when the salinity of the solutions increase. The following implications for modeling the colloidal transport of contaminants have been derived from this study: (1) The sources of the colloids are not only solubility-limited real colloids and the pseudo colloids formed by adsorption of radionuclides onto a groundwater colloid, but also from the spalled surface layers of reacted waste glasses. (2) In a repository, the local environment is likely to be glass-reaction dominated and the salt concentration is likely to be high, leading to rapid colloid agglomeration and settling; thus, colloid transport may be insignificant. (3) If large volumes of groundwater contact the glass reaction site, the precipitated colloids may become resuspended, and colloid transport may become important. (4) Under most conditions, the colloids are negatively charged and will deposit readily on positively charged surfaces. Negatively charged surfaces will, in general, facilitate colloid stability and transport

Gluten, pills and talk : assessing emergent technologies from a patients'perspective

NARCIS (Netherlands)

Veen, M.

2011-01-01

How can research in the area of celiac disease take patients into account? Celiac disease is an intolerance for gluten, for which a lifelong gluten-free diet is the only treatment currently available. The aim of this thesis is to gain insight into the everyday life of patients, so as to better align

Solid colloidal particles inducing coalescence in bitumen-in-water emulsions.

Science.gov (United States)

Legrand, J; Chamerois, M; Placin, F; Poirier, J E; Bibette, J; Leal-Calderon, F

2005-01-04

Silica particles are dispersed in the continuous phase of bitumen-in-water emulsions. The mixture remains dispersed in quiescent storage conditions. However, rapid destabilization occurs once a shear is applied. Observations under the microscope reveal that the bitumen droplets form a colloidal gel and coalesce upon application of a shear. We follow the kinetic evolution of the emulsions viscosity, eta, at constant shear rate: eta remains initially constant and exhibits a dramatic increase after a finite time, tau. We study the influence of various parameters on the evolution of tau: bitumen droplet size and volume fraction, silica diameter and concentration, shear rate, etc.

Particle Trapping and Banding in Rapid Colloidal Solidification

KAUST Repository

Elliott, J. A. W.; Peppin, S. S. L.

2011-01-01

We derive an expression for the nonequilibrium segregation coefficient of colloidal particles near a moving solid-liquid interface. The resulting kinetic phase diagram has applications for the rapid solidification of clay soils, gels, and related

The Role of Oxidative Stress in the Etiopathogenesis of Gluten-Sensitive Enteropathy Disease

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Kaplan Mustafa

2017-09-01

Full Text Available Background: The objective here is to examine the role of overall oxidative stress in the etiopathogenesis of gluten-sensitive enteropathy disease and its relationship with gluten free diet and autoantibodies.

Structural, Culinary, Nutritional and Anti-Nutritional Properties of High Protein, Gluten Free, 100% Legume Pasta.

Science.gov (United States)

Laleg, Karima; Cassan, Denis; Barron, Cécile; Prabhasankar, Pichan; Micard, Valérie

2016-01-01

Wheat pasta has a compact structure built by a gluten network entrapping starch granules resulting in a low glycemic index, but is nevertheless unsuitable for gluten-intolerant people. High protein gluten-free legume flours, rich in fibers, resistant starch and minerals are thus a good alternative for gluten-free pasta production. In this study, gluten-free pasta was produced exclusively from faba, lentil or black-gram flours. The relationship between their structure, their cooking and Rheological properties and their in-vitro starch digestion was analyzed and compared to cereal gluten-free commercial pasta. Trypsin inhibitory activity, phytic acid and α-galactosides were determined in flours and in cooked pasta. All legume pasta were rich in protein, resistant starch and fibers. They had a thick but weak protein network, which is built during the pasta cooking step. This particular structure altered pasta springiness and increased cooking losses. Black-gram pasta, which is especially rich in soluble fibers, differed from faba and lentil pasta, with high springiness (0.85 vs. 0.75) and less loss during cooking. In comparison to a commercial cereal gluten-free pasta, all the legume pasta lost less material during cooking but was less cohesive and springy. Interestingly, due to their particular composition and structure, lentil and faba pasta released their starch more slowly than the commercial gluten-free pasta during the in-vitro digestion process. Anti-nutritional factors in legumes, such as trypsin inhibitory activity and α-galactosides were reduced by up to 82% and 73%, respectively, by pasta processing and cooking. However, these processing steps had a minor effect on phytic acid. This study demonstrates the advantages of using legumes for the production of gluten-free pasta with a low glycemic index and high nutritional quality.

Building micro-soccer-balls with evaporating colloidal fakir drops

Science.gov (United States)

Gelderblom, Hanneke; Marín, Álvaro G.; Susarrey-Arce, Arturo; van Housselt, Arie; Lefferts, Leon; Gardeniers, Han; Lohse, Detlef; Snoeijer, Jacco H.

2013-11-01

Drop evaporation can be used to self-assemble particles into three-dimensional microstructures on a scale where direct manipulation is impossible. We present a unique method to create highly-ordered colloidal microstructures in which we can control the amount of particles and their packing fraction. To this end, we evaporate colloidal dispersion drops from a special type of superhydrophobic microstructured surface, on which the drop remains in Cassie-Baxter state during the entire evaporative process. The remainders of the drop consist of a massive spherical cluster of the microspheres, with diameters ranging from a few tens up to several hundreds of microns. We present scaling arguments to show how the final particle packing fraction of these balls depends on the drop evaporation dynamics, particle size, and number of particles in the system.

A re-circulated toxicity exposure chamber to evaluate hydrocarbon dispersions

International Nuclear Information System (INIS)

Fuller, C.B.; Bonner, J.S.; Bujnoch, J.D.; Ussery, S.F.; Arrambide, G.; Sterling, M.C.

2002-01-01

Traditional toxicology methods are not suitable for evaluating chemically dispersed oil which exists mostly as a colloidal suspension and as dissolved fractions. A new toxicity exposure chamber was designed with separate chambers for scaled mixing and organism exposure. The design of the chamber incorporates continuous recirculation between the mixing and exposure chamber and an upward flow in the exposure chamber. The toxicity exposure system incorporates scalable and quantitative mixing inputs with real time particle size analysis and traditional petrochemistry methods to characterize the exposure regime. Changes in dispersion were successfully translated to the organism exposure regime. The study determined the petroleum toxicity with a juvenile marine test species. Low control mortality demonstrated the usefulness of the method for testing toxicity of colloidal oil suspensions. 20 refs., 1 tab., 4 figs

Influence of process conditions on the separation behaviour of starch-gluten systems

NARCIS (Netherlands)

Zalm, van der E.E.J.; Goot, van der A.J.; Boom, R.M.

2009-01-01

Separation of wheat flour into its constituents starch and gluten was studied using a cone-cone shearing device, with emphasis on the effect of rotation rate, processing time, temperature and water content. This study confirms the two step mechanism previously proposed for the gluten migration:

Efficient degradation of gluten by a prolyl endoprotease in a gastrointestinal model: Implications for coeliac disease

NARCIS (Netherlands)

Mitea, C.; Havenaar, R.; Wouter Drijfhout, J.; Edens, L.; Dekking, L.; Koning, F.; Dekking, E.H.A.

2008-01-01

Background: Coeliac disease is caused by an immune response to gluten. As gluten proteins are proline rich they are resistant to enzymatic digestion in the gastrointestinal tract, a property that probably contributes to the immunogenic nature of gluten. Aims: This study determined the efficiency of

Colloidal suspensions hydrodynamic retention mechanisms in model porous media

International Nuclear Information System (INIS)

Salehi, N.

1996-01-01

This study deals with the retention mechanisms of colloidal particles in porous media flows, and the subsequent reduction in permeability in the case of stable and non adsorbing colloids. It combines experimental results and modelling. This study has been realised with stable dispersion of monodispersed carboxylate polystyrene latexes negatively charged injected through negatively charged polycarbonate membranes having mono-sized cylindrical pores. The mean particle diameter is smaller than the mean pore diameter. Both batch and flow experiments in Nuclepore membranes have been done. The results of batch experiments have proved no adsorption of the colloidal latex particles on the surface of the Nuclepore membranes without flow at low salinity. In flow experiments at low particle concentration, only deposition on the upstream side of the membrane have been induced by hydrodynamic forces even for non adsorbing particles without creating any permeability reduction. The retention levels are zero at low and high Peclet numbers with a maximum at intermediate values. Partial plugging was observed at higher colloid concentration even at low salinity without any upstream surface deposition. The modelling of plugging processes is achieved by considering the particle concentration, fluid rate and ratio between the mean pore diameter and the mean particle diameter. This study can be particularly useful in the fields of water treatment and of restoration of lands following radioactive contamination. (author). 96 refs., 99 figs., 29 tabs

Similar Responses of Intestinal T Cells From Untreated Children and Adults With Celiac Disease to Deamidated Gluten Epitopes.

Science.gov (United States)

Ráki, Melinda; Dahal-Koirala, Shiva; Yu, Hao; Korponay-Szabó, Ilma R; Gyimesi, Judit; Castillejo, Gemma; Jahnsen, Jørgen; Qiao, Shuo-Wang; Sollid, Ludvig M

2017-09-01

Celiac disease is a chronic small intestinal inflammatory disorder mediated by an immune response to gluten peptides in genetically susceptible individuals. Celiac disease is often diagnosed in early childhood, but some patients receive a diagnosis late in life. It is uncertain whether pediatric celiac disease is distinct from adult celiac disease. It has been proposed that gluten-reactive T cells in children recognize deamidated and native gluten epitopes, whereas T cells from adults only recognize deamidated gluten peptides. We studied the repertoire of gluten epitopes recognized by T cells from children and adults. We examined T-cell responses against gluten by generating T-cell lines and T-cell clones from intestinal biopsies of adults and children and tested proliferative response to various gluten peptides. We analyzed T cells from 14 children (2-5 years old) at high risk for celiac disease who were followed for celiac disease development. We also analyzed T cells from 6 adults (26-55 years old) with untreated celiac disease. All children and adults were positive for HLA-DQ2.5. Biopsies were incubated with gluten digested with chymotrypsin (modified or unmodified by the enzyme transglutaminase 2) or the peptic-tryptic digest of gliadin (in native and deamidated forms) before T-cell collection. Levels of T-cell responses were higher to deamidated gluten than to native gluten in children and adults. T cells from children and adults each reacted to multiple gluten epitopes. Several T-cell clones were cross-reactive, especially clones that recognized epitopes from γ-and ω-gliadin. About half of the generated T-cell clones from children and adults reacted to unknown epitopes. T-cell responses to different gluten peptides appear to be similar between adults and children at the time of diagnosis of celiac disease. Copyright © 2017 AGA Institute. Published by Elsevier Inc. All rights reserved.

Adsorption of polyelectrolytes and charged block copolymers on oxides consequences for colloidal stability

NARCIS (Netherlands)

Hoogeveen, N.G.

1996-01-01

The aim of the study described in this thesis was to examine the adsorption properties of polyelectrolytes and charged block copolymers on oxides, and the effect of these polymers on the colloidal stability of oxidic dispersions. For this purpose the interaction of some well-characterised

Shape-tailored polymer colloids on the road to become structural motifs for hierarchically organized materials.

Science.gov (United States)

Plüisch, Claudia Simone; Wittemann, Alexander

2013-12-01

Anisometric polymer colloids are likely to behave differently when compared with centrosymmetric particles. Their study may not only shine new light on the organization of matter; they may also serve as building units with specific symmetries and complexity to build new materials from them. Polymer colloids of well-defined complex geometries can be obtained by packing a limited number of spherical polymer particles into clusters with defined configurations. Such supracolloidal architectures can be fabricated at larger scales using narrowly dispersed emulsion droplets as templates. Assemblies built from at least two different types of particles as elementary building units open perspectives in selective targeting of colloids with specific properties, aiming for mesoscale building blocks with tailor-made morphologies and multifunctionality. Polymer colloids with defined geometries are also ideal to study shape-dependent properties such as the diffusion of complex particles. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

pH Triggered Recovery and Reuse of Thiolated Poly(acrylic acid) Functionalized Gold Nanoparticles with Applications in Colloidal Catalysis.

Science.gov (United States)

Ansar, Siyam M; Fellows, Benjamin; Mispireta, Patrick; Mefford, O Thompson; Kitchens, Christopher L

2017-08-08

Thiolated poly(acrylic acid) (PAA-SH) functionalized gold nanoparticles were explored as a colloidal catalyst with potential application as a recoverable catalyst where the PAA provides pH-responsive dispersibility and phase transfer capability between aqueous and organic media. This system demonstrates complete nanoparticle recovery and redispersion over multiple reaction cycles without changes in nanoparticle morphology or reduction in conversion. The catalytic activity (rate constant) was reduced in subsequent reactions when recovery by aggregation was employed, despite unobservable changes in morphology or dispersibility. When colloidal catalyst recovery employed a pH induced phase transfer between two immiscible solvents, the catalytic activity of the recovered nanoparticles was unchanged over four cycles, maintaining the original rate constant and 100% conversion. The ability to recover and reuse colloidal catalysts by aggregation/redispersion and phase transfer methods that occur at low and high pH, respectively, could be used for different gold nanoparticle catalyzed reactions that occur at different pH conditions.

Sedimentation behaviour and colloidal properties of porous, chemically modified silicas in non-aqueous solvents

NARCIS (Netherlands)

Vissers, J.P.C.; Laven, J.; Claessens, H.A.; Cramers, C.A.M.G.; Agterof, W.G.M.

1997-01-01

The sedimentation behaviour and colloidal properties of porous, chemically modified silicas dispersed in non-aqueous solvents have been studied. The free settling behaviour of non-aggregated silica suspensions could effectively be described with a modified Stokes equation that takes into account the

Biomarkers to Monitor Gluten-Free Diet Compliance in Celiac Patients

Directory of Open Access Journals (Sweden)

María de Lourdes Moreno

2017-01-01

Full Text Available Gluten-free diet (GFD is the only treatment for celiac disease (CD. There is a general consensus that strict GFD adherence in CD patients leads to full clinical and histological remission accompanied by improvement in quality of life and reduced long-term complications. Despite the importance of monitoring the GFD, there are no clear guidelines for assessing the outcome or for exploring its adherence. Available methods are insufficiently accurate to identify occasional gluten exposure that may cause intestinal mucosal damage. Serological tests are highly sensitive and specific for diagnosis, but do not predict recovery and are not useful for follow-up. The use of serial endoscopies, it is invasive and impractical for frequent monitoring, and dietary interview can be subjective. Therefore, the detection of gluten immunogenic peptides (GIP in feces and urine have been proposed as new non-invasive biomarkers to detect gluten intake and verify GFD compliance in CD patients. These simple immunoassays in human samples could overcome some key unresolved scientific and clinical problems in CD management. It is a significant advance that opens up new possibilities for the clinicians to evaluate the CD treatment, GFD compliance, and improvement in the quality of life of CD patients.

Influence of maize flour particle size on gluten-free breadmaking.

Science.gov (United States)

de la Hera, Esther; Talegón, María; Caballero, Pedro; Gómez, Manuel

2013-03-15

Maize, one of the suitable grains for coeliac consumption, is, together with rice, the most cultivated cereal in the world. However, the inclusion of maize flour in gluten-free bread is a minority and studies are scarce. This paper analyses the influence of different maize flour types and their particle sizes on the quality of two types of bread without gluten (80% and 110% water in the formulation) obtained from them. We also analysed the microstructure of the dough and its behaviour during the fermentation. Finer flours had a lower dough development during fermentation in all cases. Among the different types of flour, those whose microstructure revealed compact particles were those which had higher specific bread volume, especially when the particle size was greater. Among the formulations, the dough with more water gave breads with higher specific volume, an effect that was more important in more compact flours. The higher volume breads had lower values of hardness and resilience. The type of corn flour and mainly its particle size influence significantly the dough development of gluten-free bread during fermentation and therefore the final volume and texture of the breads obtained. The flours having coarser particle size are the most suitable for making gluten-free maize bread. © 2012 Society of Chemical Industry.

Formation of Polyelectrolyte Complex Colloid Particles between Chitosan and Pectin with Different Degree of Esterification

Science.gov (United States)

Wang, Hui; Sun, Hongyuan; He, Jieyu

2017-12-01

The effects of degree of esterification, pectin/chitosan ratio and pH on the formation of polyelectrolyte complex colloid particles between chitosan (CS) and pectin (PE) were investigated. Low methoxyl pectin (LPE) was achieved by de-esterifying high methoxyl pectin (HPE) with pectin methyl esterase. Turbidity titration and colorimetric method was used to determine the stability of complex colloid particles. The structure and morphology of complex particles were characterized by FTIR and TEM. When pectin solution was dropped into chitosan solution, complex colloidal dispersion was stable as PE/CS mass ratio was no more than 3:2. Colloidal particles of HPE-CS complex coagulated at larger ratio of PE/CS than LPE-CS. The maximum complex occurred at pH 6.1 for HPE-CS and pH 5.7 for LPE-CS, and decreasing pH leaded to the dissociation of complex particles. Electrostatic interactions between carboxyl groups on pectin and amino groups on chitosan were confirmed by FTIR. Colloidal particle sizes ranged from about 100 nm to 400 nm with spherical shape.

The Overlap between Irritable Bowel Syndrome and Non-Celiac Gluten Sensitivity: A Clinical Dilemma

Directory of Open Access Journals (Sweden)

Archita Makharia

2015-12-01

Full Text Available The spectrum of gluten-related disorders has widened in recent times and includes celiac disease, non-celiac gluten sensitivity, and wheat allergy. The complex of symptoms associated with these diseases, such as diarrhea, constipation or abdominal pain may overlap for the gluten related diseases, and furthermore they can be similar to those caused by various other intestinal diseases, such as irritable bowel syndrome (IBS. The mechanisms underlying symptom generation are diverse for all these diseases. Some patients with celiac disease may remain asymptomatic or have only mild gastrointestinal symptoms and thus may qualify for the diagnosis of IBS in the general clinical practice. Similarly, the overlap of symptoms between IBS and non-celiac gluten sensitivity (NCGS often creates a dilemma for clinicians. While the treatment of NCGS is exclusion of gluten from the diet, some, but not all, of the patients with IBS also improve on a gluten-free diet. Both IBS and NCGS are common in the general population and both can coexist with each other independently without necessarily sharing a common pathophysiological basis. Although the pathogenesis of NCGS is not well understood, it is likely to be heterogeneous with possible contributing factors such as low-grade intestinal inflammation, increased intestinal barrier function and changes in the intestinal microbiota. Innate immunity may also play a pivotal role. One possible inducer of innate immune response has recently been reported to be amylase-trypsin inhibitor, a protein present in wheat endosperm and the source of flour, along with the gluten proteins.

Paediatric Patients with Coeliac Disease on a Gluten-Free Diet: Nutritional Adequacy and Macro- and Micronutrient Imbalances.

Science.gov (United States)

Sue, Alison; Dehlsen, Kate; Ooi, Chee Y

2018-01-22

A strict, lifelong gluten-free diet is the cornerstone for management of coeliac disease. Elimination of gluten from the diet may be associated with nutritional imbalance; however, the completeness of this diet in energy and macro- and micronutrients in children is not well described. Understanding the nutritional adequacy of the gluten-free diet in children during this critical period of growth and development when dietary intake is strongly influential is important. Children, regardless of whether they have eliminated gluten from their diet, have a tendency to consume excess fat and insufficient fibre, iron, vitamin D and calcium, compared to recommendations. In the context of a gluten-free diet, these imbalances may be worsened or have more significant consequences. Paediatric studies have demonstrated that intakes of folate, magnesium, zinc and selenium may decrease on a gluten-free diet. Nutritional inadequacies may be risks of a gluten-free diet in a paediatric population. The potential implications of these inadequacies, both short and long term, remain unclear and warrant further investigation and clarification.

76 FR 79196 - Gluten in Drug Products; Request for Information and Comments

Science.gov (United States)

2011-12-21

... individuals (Refs. 1 and 2). In these individuals, the symptoms of celiac disease are triggered by the... its deliberations about ways to help individuals with celiac disease avoid the presence of gluten in.... Celiac Disease Celiac disease (also known as celiac sprue and gluten-sensitive enteropathy) is an immune...

[Extruded rice flour as a gluten substitute in the poduction of rice bread].

Science.gov (United States)

Clerici, Maria Teresa Pedrosa Silva; El-Dash, Ahmed A

2006-09-01

Research regarding the production of gluten-free bread (GFB) is very important nutritionally, technically and economically speaking, both to celiac patients and to developing countries who import wheat. The main technological problem in the production of GFB is obtaining a gluten substitute that is both inexpensive and capable of retaining gas during bread fermentation and baking. The use of gelatinized starch as an alternative for gluten seems promising. In this project, rice bread was made using pregelatinized extruded rice flour as a gluten substitute. Pre-gelatinized rice flours (PRF) were manufactured in a single screw Brabender extruder, varying extrusion temperature (108-192 degrees C) and the moisture of the raw material (19.2 - 24.8%), and were used in a proportion of 10 g for every 100 g of raw rice flour, in the production of gluten-free bread. Results showed that rice flour extruded at a high temperature (180 degrees) and low moisture content (20%), rendered bread with the best technological characteristics, presenting crust and crumb color similar to those of conventional wheat bread, although with volume and texture not as satisfactory in the same comparison.

The effect of corrosion product colloids on actinide transport

International Nuclear Information System (INIS)

Gardiner, M.P.; Smith, A.J.; Williams, S.J.

1992-01-01

The near field of the proposed UK repository for ILW/LLW will contain containers of conditioned waste in contact with a cementious backfill. It will contain significant quantities of iron and steel, Magnox and Zircaloy. Colloids deriving from their corrosion products may possess significant sorption capacity for radioelements. If the colloids are mobile in the groundwater flow, they could act as a significant vector for activity transport into the far field. The desorption of plutonium and americium from colloidal corrosion products of iron and zirconium has been studied under chemical conditions representing the transition from the near field to the far field. Desorption R d values of ≥ 5 x 10 6 ml g -1 were measured for both actinides on these oxides and hydroxides when actinide sorption took place under the near-field conditions and desorption took place under the far-field conditions. Desorption of the actinides occurred slowly from the colloids under far-field conditions when the colloids had low loadings of actinide and more quickly at high loadings of actinide. Desorbed actinide was lost to the walls of the experimental vessel. (author)

Fecal Gluten Peptides Reveal Limitations of Serological Tests and Food Questionnaires for Monitoring Gluten-Free Diet in Celiac Disease Patients

Science.gov (United States)

Comino, Isabel; Fernández-Bañares, Fernando; Esteve, María; Ortigosa, Luís; Castillejo, Gemma; Fambuena, Blanca; Ribes-Koninckx, Carmen; Sierra, Carlos; Rodríguez-Herrera, Alfonso; Salazar, José Carlos; Caunedo, Ángel; Marugán-Miguelsanz, J M; Garrote, José Antonio; Vivas, Santiago; lo Iacono, Oreste; Nuñez, Alejandro; Vaquero, Luis; Vegas, Ana María; Crespo, Laura; Fernández-Salazar, Luis; Arranz, Eduardo; Jiménez-García, Victoria Alejandra; Antonio Montes-Cano, Marco; Espín, Beatriz; Galera, Ana; Valverde, Justo; Girón, Francisco José; Bolonio, Miguel; Millán, Antonio; Cerezo, Francesc Martínez; Guajardo, César; Alberto, José Ramón; Rosinach, Mercé; Segura, Verónica; León, Francisco; Marinich, Jorge; Muñoz-Suano, Alba; Romero-Gómez, Manuel; Cebolla, Ángel; Sousa, Carolina

2016-01-01

Objectives: Treatment for celiac disease (CD) is a lifelong strict gluten-free diet (GFD). Patients should be followed-up with dietary interviews and serology as CD markers to ensure adherence to the diet. However, none of these methods offer an accurate measure of dietary compliance. Our aim was to evaluate the measurement of gluten immunogenic peptides (GIP) in stools as a marker of GFD adherence in CD patients and compare it with traditional methods of GFD monitoring. Methods: We performed a prospective, nonrandomized, multicenter study including 188 CD patients on GFD and 84 healthy controls. Subjects were given a dietary questionnaire and fecal GIP quantified by enzyme-linked immunosorbent assay (ELISA). Serological anti-tissue transglutaminase (anti-tTG) IgA and anti-deamidated gliadin peptide (anti-DGP) IgA antibodies were measured simultaneously. Results: Of the 188 celiac patients, 56 (29.8%) had detectable GIP levels in stools. There was significant association between age and GIP in stools that revealed increasing dietary transgressions with advancing age (39.2% in subjects ≥13 years old) and with gender in certain age groups (60% in men ≥13 years old). No association was found between fecal GIP and dietary questionnaire or anti-tTG antibodies. However, association was detected between GIP and anti-DGP antibodies, although 46 of the 53 GIP stool-positive patients were negative for anti-DGP. Conclusions: Detection of gluten peptides in stools reveals limitations of traditional methods for monitoring GFD in celiac patients. The GIP ELISA enables direct and quantitative assessment of gluten exposure early after ingestion and could aid in the diagnosis and clinical management of nonresponsive CD and refractory CD. Trial registration number NCT02711397. PMID:27644734

Orientational Order of Carbon Nanotube Guests in a Nematic Host Suspension of Colloidal Viral Rods

NARCIS (Netherlands)

Puech, N.; Dennison, M.; Blanc, C.; van der Schoot, P.; van Roij, R.; Poulin, P.; Grelet, E.

2012-01-01

In order to investigate the coupling between the degrees of alignment of elongated particles in binary nematic dispersions, surfactant stabilized single-wall carbon nanotubes (CNTs) have been added to nematic suspensions of colloidal rodlike viruses in aqueous solution. We have independently

Orientational order of carbon nanotube guests in a nematic host suspension of colloidal viral rods

NARCIS (Netherlands)

Puech, N.; Dennison, M.; Blanc, C.; Schoot, van der P.P.A.M.; Dijkstra, Marjolein; Roij, van R.; Poulin, P.; Grelet, E.

2012-01-01

In order to investigate the coupling between the degrees of alignment of elongated particles in binary nematic dispersions, surfactant stabilized single-wall carbon nanotubes (CNTs) have been added to nematic suspensions of colloidal rodlike viruses in aqueous solution. We have independently

Characterization of the Bread Made with Durum Wheat Semolina Rendered Gluten Free by Sourdough Biotechnology in Comparison with Commercial Gluten-Free Products.

Science.gov (United States)

Rizzello, Carlo Giuseppe; Montemurro, Marco; Gobbetti, Marco

2016-09-01

Durum wheat semolina was fermented with sourdough lactic acid bacteria and fungal proteases aiming at a complete gluten hydrolysis. The gluten-free (GF) semolina, added with naturally GF ingredients and structuring agents, was used to produce bread (rendered GF bread; rGFB) at industrial level. An integrated approach including the characterization of the main chemical, nutritional, structural, and sensory features was used to compare rGFB to a gluten-containing bread and to 5 commercial naturally GF breads. High-performance liquid chromatography was used for free amino acids (FAAs), organic acids, and ethanol analysis. A methanolic extract was used for determining total phenols and antioxidant activity. The bread characterization also included the analysis of dietary fibers, mycotoxins, vitamins, and heavy metals. Beyond chemical analysis, nutritional profile was evaluated considering the in vitro protein digestibility and the predicted glycemic index, while the instrumental texture profile analysis was performed to investigate the structure and the physical/mechanical properties of the baked goods. Beyond the huge potential of market expansion, the main advantages of durum wheat semolina rendered GF can be resumed in the high availability of FAAs, the high protein digestibility, the low starch hydrolysis index, and the better technological properties of bread compared to the commercial GF products currently present on the market. Vitamins, minerals, and dietary fiber profiles are comparable to those of gluten-containing wheat bread. Also the sensory profile, determined by a panel test, can be considered the most similar to those of conventional baked goods, showing all the sourdough bread classic attributes. © 2016 Institute of Food Technologists®

Improvement of Emulsifying Properties of Wheat Gluten Hydrolysate λ-Carrageenan Conjugates

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Jin-Shui Wang

2006-01-01

Full Text Available Gluten hydrolysate was prepared through limited enzymatic hydrolysis of wheat gluten resulting from the byproducts of wheat starch. The enzyme applied in the present study was Protamex. Response surface methodology was used to investigate the effects of pH, gluten hydrolysate (GHPλ-carrageenan (C ratio and reaction time on emulsifying properties of the GHP-C conjugate. The regression model for emulsion activity index (EAI was significant at p=0.001, while reaction time had a significant effect on EAI of the conjugate with regression coefficient of 4.25. The interactions of pH and GHP/ C ratio, and GHP/C ratio and reaction time significantly affected the EAI of the conjugate. Both the emulsifying property and nitrogen solubility index (NSI of GHP-C conjugate prepared under the optimal conditions increased more remarkably, compared to the control. The denaturation temperature of GHP-C conjugate obviously increased compared to wheat gluten. The addition of GHP-C conjugate had different effects on dough characteristics. Moreover, this conjugate can delay the increase in the bread crumb firmness during storage. It demonstrated that this conjugate couldimprove the dough characteristics and had anti-staling properties of bread.

Addition of Vital Wheat Gluten to Enhance the Quality Characteristics of Frozen Dough Products

Directory of Open Access Journals (Sweden)

Virginia Giannou

2016-01-01

Full Text Available The aim of this study was to enhance the quality and sensory characteristics of bread made from frozen dough. Both white and whole-wheat flour were used. In order to improve dough strength and stability during frozen storage, samples were supplemented with vital wheat gluten at the levels of 2%, 4%, 5%, and 6% of flour weight. The characteristics of baked samples were determined through weight loss, specific volume, crust, and crumb color, texture, and sensory evaluation. Dough behavior at sub-zero temperatures was further examined for control samples and samples with 6% gluten using Differential Scanning Calorimetry (DSC, while their low molecular sugar content (fructose, glucose, sucrose was measured using High Pressure Liquid Chromatography (HPLC, as it can be associated with yeast viability and dough freezing point depression. The most stable samples were those with 4% and 6% gluten (for white flour and those with 4% and 5% gluten (for whole-wheat flour. Gluten addition raised the freezing point of dough samples and preserved low molecular sugar generation after prolonged storage.

Gluten-free diet in children: an approach to a nutritionally adequate and balanced diet.

Science.gov (United States)

Penagini, Francesca; Dilillo, Dario; Meneghin, Fabio; Mameli, Chiara; Fabiano, Valentina; Zuccotti, Gian Vincenzo

2013-11-18

Gluten-free diet (GFD) is the cornerstone treatment for celiac disease (CD). GFD implies a strict and lifelong elimination from the diet of gluten, the storage protein found in wheat, barley, rye and hybrids of these grains, such as kamut and triticale. The absence of gluten in natural and processed foods, despite being the key aspect of GFD, may lead to nutritional consequences, such as deficits and imbalances. The nutritional adequacy of GFD is particularly important in children, this the age being of maximal energy and nutrient requirements for growth, development and activity. In recent years, attention has focused on the nutritional quality of gluten-free products (GFPs) available in the market. It is well recognized that GFPs are considered of lower quality and poorer nutritional value compared to the gluten-containing counterparts. The present review focuses on the nutritional adequacy of GFD at the pediatric age, with the aim being to increase awareness of the potential complications associated with this diet, to identify strategies in order to avoid them and to promote a healthier diet and lifestyle in children with CD.

Transport of a Two-Member Decay Chain of Radionuclides Through a Discrete Fracture in a Porous Rock Matrix in the Presence of Colloids

International Nuclear Information System (INIS)

Tien, N.-C.; Li Shihhai

2002-01-01

Many physical and chemical processes dominate the transport of radionuclides in groundwater. Among these processes, the decay chain process of radionuclides was frequently disregarded in previous research. However, the daughter products may travel much farther than their parents along the fracture. Therefore, some models neglecting the effect of the decay chain may underestimate the transport radionuclide concentration in geological media. The transport of radionuclides in groundwater is also controlled by colloidal particles. The radionuclides may be enhanced or retarded by the colloids, according to the mobility of these colloidal particles. This work describes a novel model of the transport of a two-member decay chain of radionuclides through a discrete fracture in a porous rock matrix in the presence of colloids. The model addresses the following processes: (a) advective transport in the fracture, (b) mechanical dispersion and molecular diffusion along the fracture, (c) molecular diffusion from the fracture to the rock matrix, (d) adsorption onto the fracture wall, (e) adsorption in the rock matrix, and (f) radioactive decay. Furthermore, colloids are assumed to be excluded from the matrix pores because of their size. A fully developed concentration profile system with nonreactive colloids is used to understand the effect of colloidal sizes by using hydrodynamic chromatography. The external forces acting on the colloid surface, such as the inertial, the van der Waals attractive force, the double layer force, and the gravitational force are accounted for. The parameters, the average velocity of the colloid, the dispersion coefficient of the colloid, and the distribution coefficient of radionuclides with colloids are modified according to the colloidal size. The transport equations for the parent radionuclides are solved analytically using the Laplace transformation and inversion method. However, for the transformed solution of the daughter products along the

Gluten causes gastrointestinal symptoms in subjects without celiac disease: a double-blind randomized placebo-controlled trial.

Science.gov (United States)

Biesiekierski, Jessica R; Newnham, Evan D; Irving, Peter M; Barrett, Jacqueline S; Haines, Melissa; Doecke, James D; Shepherd, Susan J; Muir, Jane G; Gibson, Peter R

2011-03-01

Despite increased prescription of a gluten-free diet for gastrointestinal symptoms in individuals who do not have celiac disease, there is minimal evidence that suggests that gluten is a trigger. The aims of this study were to determine whether gluten ingestion can induce symptoms in non-celiac individuals and to examine the mechanism. A double-blind, randomized, placebo-controlled rechallenge trial was undertaken in patients with irritable bowel syndrome in whom celiac disease was excluded and who were symptomatically controlled on a gluten-free diet. Participants received either gluten or placebo in the form of two bread slices plus one muffin per day with a gluten-free diet for up to 6 weeks. Symptoms were evaluated using a visual analog scale and markers of intestinal inflammation, injury, and immune activation were monitored. A total of 34 patients (aged 29-59 years, 4 men) completed the study as per protocol. Overall, 56% had human leukocyte antigen (HLA)-DQ2 and/or HLA-DQ8. Adherence to diet and supplements was very high. Of 19 patients (68%) in the gluten group, 13 reported that symptoms were not adequately controlled compared with 6 of 15 (40%) on placebo (P=0.0001; generalized estimating equation). On a visual analog scale, patients were significantly worse with gluten within 1 week for overall symptoms (P=0.047), pain (P=0.016), bloating (P=0.031), satisfaction with stool consistency (P=0.024), and tiredness (P=0.001). Anti-gliadin antibodies were not induced. There were no significant changes in fecal lactoferrin, levels of celiac antibodies, highly sensitive C-reactive protein, or intestinal permeability. There were no differences in any end point in individuals with or without DQ2/DQ8. "Non-celiac gluten intolerance" may exist, but no clues to the mechanism were elucidated.

The Availability of Food for a Gluten-free Diet and Possibilities at Dining Establishments

Directory of Open Access Journals (Sweden)

Olga Regnerová

2016-01-01

Full Text Available The aim of the paper is to evaluate options for customers-consumers with a gluten-free diet (coeliac disease patients at food establishments on the Czech market. A gluten-free diet is the only treatment for patients with coeliac disease and it significantly affects their health. The availability of food was investigated during February and March 2014 in three types of food operations. These establishments were visited in forty-three urban, rural and non-residential areas, and the availability of food for people with a gluten-free diet was investigated through interviews at 226 facilities. The preferences of the specific group of customers with a gluten-free diet were determined through comprehensive comparative research. The data was collected from February to June 2014, and 441 respondents were interviewed. The survey revealed that the majority of consumers who must follow this diet fall in the age group of up to 40 years old. This age group consists of preschool and school-age children, students and people of working age who frequently eat away from home. The paper deals with the evaluation of the level of public food services used by customers with gluten intolerance and gives some recommendations for improving the availability and offer of food for a gluten-free diet in selected types of hospitality establishments.

Gluten-Free Diet Only during Pregnancy Efficiently Prevents Diabetes in NOD Mouse Offspring

DEFF Research Database (Denmark)

Antvorskov, Julie C; Josefsen, Knud; Haupt-Jorgensen, Martin

2016-01-01

Studies have documented that the pathogenesis of autoimmune diabetes is influenced by the intake of gluten. Aims. To investigate the importance of gluten exposure during pregnancy and the subsequent development of autoimmune diabetes in offspring. Methods. Nonobese diabetic mice were divided into...

Factors governing long-term adherence to a gluten-free diet in adult patients with coeliac disease.

Science.gov (United States)

Villafuerte-Galvez, J; Vanga, R R; Dennis, M; Hansen, J; Leffler, D A; Kelly, C P; Mukherjee, R

2015-09-01

A strict gluten-free diet is the cornerstone of treatment for coeliac disease. Studies of gluten-free diet adherence have rarely used validated instruments. There is a paucity of data on long-term adherence to the gluten-free diet in the adult population. To determine the long-term adherence to the gluten-free diet and potential associated factors in a large coeliac disease referral centre population. We performed a mailed survey of adults with clinically, serologically and histologically confirmed coeliac disease diagnosed ≥5 years prior to survey. The previously validated Celiac Disease Adherence Test was used to determine adherence. Demographic, socio-economic and potentially associated factors were analysed with adherence as the outcome. The response rate was 50.1% of 709 surveyed, the mean time on a gluten-free diet 9.9 ± 6.4 years. Adequate adherence (celiac disease adherence test score 75% of respondents. Perceived cost remains a barrier to adherence. Perceptions of effectiveness of gluten-free diet as well as its knowledge, are potential areas for intervention. © 2015 John Wiley & Sons Ltd.

Antibacterial Activity of Electrochemically Synthesized Colloidal Silver Nanoparticles Against Hospital-Acquired Infections

Science.gov (United States)

Thuc, Dao Tri; Huy, Tran Quang; Hoang, Luc Huy; Hoang, Tran Huy; Le, Anh-Tuan; Anh, Dang Duc

2017-06-01

This study evaluated the antibacterial activity of electrochemically synthesized colloidal silver nanoparticles (AgNPs) against hospital-acquired infections. Colloidal AgNPs were synthesized via a single process using bulk silver bars, bi-distilled water, trisodium citrate, and direct current voltage at room temperature. Colloidal AgNPs were characterized by transmission electron microscopy, field-emission scanning electron microscopy, and energy-dispersive x-ray analyses. The antibacterial activity of colloidal AgNPs against four bacterial strains isolated from clinical samples, including methicillin-resistant Staphylococcus aureus, Escherichia coli O157:H7, multidrug-resistant Pseudomonas aeruginosa, and carbapenem-resistant Klebsiella pneumonia, was evaluated by disc diffusion, minimum inhibitory concentration (MIC), and ultrathin sectioning electron microscopy. The results showed that the prepared AgNPs were 19.7 ± 4.3 nm in size, quasi-spherical, and of high purity. Zones of inhibition approximately 6-10 mm in diameter were found, corresponding to AgNPs concentrations of 50 μg/mL to 100 μg/mL. The MIC results revealed that the antibacterial activity of the prepared AgNPs was strongly dependent on the concentration and strain of the tested bacteria.

Polymer depletion-driven cluster aggregation and initial phase separation in charged nanosized colloids

Science.gov (United States)

Gögelein, Christoph; Nägele, Gerhard; Buitenhuis, Johan; Tuinier, Remco; Dhont, Jan K. G.

2009-05-01

We study polymer depletion-driven cluster aggregation and initial phase separation in aqueous dispersions of charge-stabilized silica spheres, where the ionic strength and polymer (dextran) concentration are systematically varied, using dynamic light scattering and visual observation. Without polymers and for increasing salt and colloid content, the dispersions become increasingly unstable against irreversible cluster formation. By adding nonadsorbing polymers, a depletion-driven attraction is induced, which lowers the stabilizing Coulomb barrier and enhances the cluster growth rate. The initial growth rate increases with increasing polymer concentration and decreases with increasing polymer molar mass. These observations can be quantitatively understood by an irreversible dimer formation theory based on the classical Derjaguin, Landau, Verwey, and Overbeek pair potential, with the depletion attraction modeled by the Asakura-Oosawa-Vrij potential. At low colloid concentration, we observe an exponential cluster growth rate for all polymer concentrations considered, indicating a reaction-limited aggregation mechanism. At sufficiently high polymer and colloid concentrations, and lower salt content, a gas-liquidlike demixing is observed initially. Later on, the system separates into a gel and fluidlike phase. The experimental time-dependent state diagram is compared to the theoretical equilibrium phase diagram obtained from a generalized free-volume theory and is discussed in terms of an initial reversible phase separation process in combination with irreversible aggregation at later times.

In vivo gluten challenge in coeliac disease

Directory of Open Access Journals (Sweden)

HJ Ellis

2001-01-01

Full Text Available In vivo gluten challenge has been used since the early 1950s to study the role of cereal fractions in celiac disease. While early studies relied on crude indicators of celiac toxicity, the advent of jejunal biopsy and sophisticated immunohistochemical techniques has allowed accurate studies to be performed. Studies to determine the nature of the cereal component that is toxic to patients with celiac disease have concentrated on wheat because of its nutritional importance. A number of in vitro studies indicated the presence of one or more celiac-activating epitopes with the N-terminus of the A-gliadin molecule. In vivo challenge with three synthetic peptides subsequently indicated the toxicity of a peptide corresponding to amino acids 31 to 49 of A-gliadin. In vivo gluten challenge is the gold standard for the assessment of celiac toxicity; however, jejunal biopsy is a relatively invasive procedure, thus, other methods have been investigated. Direct infusion of the rectum with gluten has been shown to result in an increase in mucosal intraepithelial lymphocytes, occurring only in celiac patients. This method has been used to study the celiac toxicity of gliadin subfractions. The in vitro technique of small intestinal biopsy organ culture is also a useful tool and appears to give the same results as in vivo challenge. The importance of tiny amounts of gliadin in the diet, such as that which occurs in wheat starch, has been studied by in vivo challenge; this technique has clarified the position of oats in the gluten-free diet. Several studies suggest that this cereal may be included in the diet of most adult celiac patients. Studies of the transport of gliadin across the enterocyte following ingestion or challenge suggest that gliadin may be metabolized by a different pathway in celiac disease. This could result in an abnormal presentation to the immune system, triggering a pathogenic rather than a tolerogenic response.

Gluten-Free Diet in Children: An Approach to a Nutritionally Adequate and Balanced Diet

OpenAIRE

Penagini, Francesca; Dilillo, Dario; Meneghin, Fabio; Mameli, Chiara; Fabiano, Valentina; Zuccotti, Gian Vincenzo

2013-01-01

Gluten-free diet (GFD) is the cornerstone treatment for celiac disease (CD). GFD implies a strict and lifelong elimination from the diet of gluten, the storage protein found in wheat, barley, rye and hybrids of these grains, such as kamut and triticale. The absence of gluten in natural and processed foods, despite being the key aspect of GFD, may lead to nutritional consequences, such as deficits and imbalances. The nutritional adequacy of GFD is particularly important in children, this the a...

Colloid Transport and Retention

DEFF Research Database (Denmark)

Yuan, Hao; Shapiro, Alexander

2012-01-01

related to historical prospective, synthesis, characterization, theoretical modeling and application of unique class of colloidal materials starting from colloidal gold to coated silica colloid and platinum, titania colloids. This book is unique in its design, content, providing depth of science about...

Silver nanoparticle colloids with γ-cyclodextrin: enhanced stability and Gibbs–Marangoni flow

Energy Technology Data Exchange (ETDEWEB)

Amiri, Setareh; Duroux, Laurent; Larsen, Kim Lambertsen, E-mail: kll@bio.aau.dk [Aalborg University, Department of Chemistry and Bioscience (Denmark)

2015-01-15

Although cyclodextrins (CD) are effective stabilizers for metal nanoparticle colloids, differences between α-, β- and γ-CD in stabilizing such colloids have not been previously reported. In this study, silver nanoparticles (AgNP) were synthesized using NaBH{sub 4} as reducing agent and cyclodextrins as stabilizers. Long-term stability of AgNP colloids in equilibrium conditions showed no marked differences between CD types. Transmission electron microscopy and quantitative image analysis revealed only marginal differences in particle sizes for CD-AgNP, although statistically significant. CD-AgNP colloids showed dispersed particles with average diameters of 7.3 ± 2.2, 6.3 ± 2.9 and 4.9 ± 1.9 nm for α-, β- and γ-CD, respectively, and with similar ζ-potentials about −25 to −30 mV. AgNP without CD showed bigger and aggregated particles of 15.0 ± 2.0 nm with lower ζ-potentials of about −40 mV. When subjected to centrifugal forces, i.e. non-equilibrium conditions, γ-CD was markedly more efficient than α- and β-CD in stabilizing the colloids. Drying patterns of colloid droplets showed a typical self-pinned coffee ring for all but the colloid stabilized by γ-CD, which showed a pattern resulting from a dominant Gibbs–Marangoni flow inside the drying droplet. Calculations using the Derjaguin, Landau, Verwey and Overbeek (DLVO) theory supported the stabilizing effect of CD in equilibrium conditions; it however did not provide clues for the superior stabilization by γ-CD in conditions of hydrodynamic stress.

Silver nanoparticle colloids with γ-cyclodextrin: enhanced stability and Gibbs–Marangoni flow

International Nuclear Information System (INIS)

Amiri, Setareh; Duroux, Laurent; Larsen, Kim Lambertsen

2015-01-01

Although cyclodextrins (CD) are effective stabilizers for metal nanoparticle colloids, differences between α-, β- and γ-CD in stabilizing such colloids have not been previously reported. In this study, silver nanoparticles (AgNP) were synthesized using NaBH 4 as reducing agent and cyclodextrins as stabilizers. Long-term stability of AgNP colloids in equilibrium conditions showed no marked differences between CD types. Transmission electron microscopy and quantitative image analysis revealed only marginal differences in particle sizes for CD-AgNP, although statistically significant. CD-AgNP colloids showed dispersed particles with average diameters of 7.3 ± 2.2, 6.3 ± 2.9 and 4.9 ± 1.9 nm for α-, β- and γ-CD, respectively, and with similar ζ-potentials about −25 to −30 mV. AgNP without CD showed bigger and aggregated particles of 15.0 ± 2.0 nm with lower ζ-potentials of about −40 mV. When subjected to centrifugal forces, i.e. non-equilibrium conditions, γ-CD was markedly more efficient than α- and β-CD in stabilizing the colloids. Drying patterns of colloid droplets showed a typical self-pinned coffee ring for all but the colloid stabilized by γ-CD, which showed a pattern resulting from a dominant Gibbs–Marangoni flow inside the drying droplet. Calculations using the Derjaguin, Landau, Verwey and Overbeek (DLVO) theory supported the stabilizing effect of CD in equilibrium conditions; it however did not provide clues for the superior stabilization by γ-CD in conditions of hydrodynamic stress

Orientational order of carbon nanotube guests in a nematic host suspension of colloidal viral rods