3,056 research outputs found
Diversity of oat varieties in eliciting the early inflammatory events in celiac disease
Purpose
Celiac disease (CD) is an autoimmune enteropathy, triggered by dietary gluten. The only treatment is a strict gluten-free diet. Oats are included in the list of gluten-free ingredients by European Regulation, but the safety of oats in CD is still a matter of debate. The present study examined the capability of different oat cultivars of activating the gliadin-induced transglutaminase-2 (TG2)-dependent events in some in vitro models of CD. In addition, we compared this capability with the electrophoresis pattern of peptic\u2013tryptic digests of the proteins of the oat cultivars.
Methods
K562(S) cells agglutination, transepithelial electrical resistance of T84-cell monolayers, intracellular levels of TG2 and phosphorylated form of protein 42\u201344 in T84 cells were the early gliadin-dependent events studied.
Results
The results showed that the Nave oat cultivar elicited these events, whereas Irina and Potenza varieties did not. The ability of a cultivar to activate the above-described events was associated with the electrophoretic pattern of oat proteins and their reactivity to anti-gliadin antibodies.
Conclusion
We found significant differences among oat cultivars in eliciting the TG2-mediated events of CD inflammation. Therefore, the safety of an oat cultivar in CD might be screened in vitro by means of biochemical and biological assays, before starting a clinical trial to definitely assess its safety
Targeting cattle for malaria elimination: marked reduction of Anopheles arabiensis survival for over six months using a slow-release ivermectin implant formulation
BACKGROUND: Mosquitoes that feed on animals can survive and
mediate residual transmission of malaria even after most humans
have been protected with insecticidal bednets or indoor residual
sprays. Ivermectin is a widely-used drug for treating parasites
of humans and animals that is also insecticidal, killing
mosquitoes that feed on treated subjects. Mass administration of
ivermectin to livestock could be particularly useful for
tackling residual malaria transmission by zoophagic vectors that
evade human-centred approaches. Ivermectin comes from a
different chemical class to active ingredients currently used to
treat bednets or spray houses, so it also has potential for
mitigating against emergence of insecticide resistance. However,
the duration of insecticidal activity obtained with ivermectin
is critical to its effectiveness and affordability. RESULTS: A
slow-release formulation for ivermectin was implanted into
cattle, causing 40 weeks of increased mortality among Anopheles
arabiensis that fed on them. For this zoophagic vector of
residual malaria transmission across much of Africa, the
proportion surviving three days after feeding (typical mean
duration of a gonotrophic cycle in field populations) was
approximately halved for 25 weeks. CONCLUSIONS: This implantable
ivermectin formulation delivers stable and sustained
insecticidal activity for approximately 6 months. Residual
malaria transmission by zoophagic vectors could be suppressed by
targeting livestock with this long-lasting formulation, which
would be impractical or unacceptable for mass treatment of human
populations
Synthesis, characterisation and crystal structure of a three-dimensional network of an h-bonded Ni (II) Hexametylenetetramine complex
A three-dimensional network of H-bonding nickel (II) hexamethylenetetramine complex has been synthesized and characterised and its structure determined by single crystal X-ray diffraction studies which show that [Ni(H2O)6](HMTA)2Cl32.4H2O crystallizes in the triclinic crystal system with space group PĪ, a = 9.2955(4), b = 9.3187(2), c = 9.3996 Ǻ, α = 119.4160(10), β = 94.4940(10), ɣ = 100.8680(10)º, V =682.47(4) Å3 and z = 1. The nickel atoms are each bonded to six aquo ligands giving an octahedral geometry. The ligand hexamethylenetetramine (HMTA) and chloride ions are bonded to water molecules through hydrogen bonding. Thermal studies show a decomposition pattern corresponding to the loss of the coordinated and uncoordinated water molecules, chloride ions and HMTA ligand in the form of a mixture of gases
Performance Modeling of Fresnel-Based CPV Systems: Effects of Deformations under Real Operation Conditions
Getting a lower energy cost has always been a challenge for concentrated photovoltaic. The FK concentrator enhances the performance (efficiency, acceptance angle and manufacturing tolerances) of the conventional CPV system based on a Fresnel primary stage and a secondary lens, while keeping its simplicity and potentially low‐cost manufacturing. At the same time F‐XTP (Fresnel lens+reflective prism), at the first glance has better cost potential but significantly higher sensitivity to manufacturing errors. This work presents comparison of these two approaches applied to two main technologies of Fresnel lens production (PMMA and Silicone on Glass) and effect of standard deformations that occur under real operation condition
Exciton and trion dynamics in atomically thin MoSe2 and WSe2: effect of localization
We present a detailed investigation of the exciton and trion dynamics in naturally doped MoSe2 and WSe2 single atomic layers as a function of temperature in the range 10-300K under above band-gap laser excitation. By combining time-integrated and time-resolved photoluminescence (PL) spectroscopy we show the importance of exciton and trion localization in both materials at low temperatures. We also reveal the transition to delocalized exciton complexes at higher temperatures where the exciton and trion thermal energy exceeds the typical localization energy. This is accompanied with strong changes in PL including suppression of the trion PL and decrease of the trion PL life-time, as well as significant changes for neutral excitons in the temperature dependence of the PL intensity and appearance of a pronounced slow PL decay component. In MoSe2 and WSe2 studied here, the temperatures where such strong changes occur are observed at around 100 and 200 K, respectively, in agreement with their inhomogeneous PL linewidth of 8 and 20 meV at T~10K. The observed behavior is a result of a complex interplay between influences of the specific energy ordering of bright and dark excitons in MoSe2 and WSe2, sample doping, trion and exciton localization and various temperature-dependent non-radiative processes
Microbial β-glucosidases from cow rumen metagenome enhance the saccharification of lignocellulose in combination with commercial cellulase cocktail
Background A complete saccharification of plant polymers is the critical step in the efficient production of bio-alcohols. Beta-glucosidases acting in the degradation of intermediate gluco-oligosaccharides produced by cellulases limit the yield of the final product. Results In the present work, we have identified and then successfully cloned, expressed, purified and characterised 4 highly active beta-glucosidases from fibre-adherent microbial community from the cow rumen. The enzymes were most active at temperatures 45–55°C and pH 4.0-7.0 and exhibited high affinity and activity towards synthetic substrates such as p-nitrophenyl-beta-D-glucopyranoside (p NPbetaG) and p NP-beta-cellobiose, as well as to natural cello-oligosaccharides ranging from cellobiose to cellopentaose. The apparent capability of the most active beta-glucosidase, herein named LAB25g2, was tested for its ability to improve, at low dosage (31.25 units g-1 dry biomass, using p NPbetaG as substrate), the hydrolysis of pre-treated corn stover (dry matter content of 20%; 350 g glucan kg-1 dry biomass) in combination with a beta-glucosidase-deficient commercial Trichoderma reseei cellulase cocktail (5 units g-1 dry biomass in the basis of p NPbetaG). LAB25g2 increased the final hydrolysis yield by a factor of 20% (44.5 ± 1.7% vs. 34.5 ± 1.5% in control conditions) after 96–120 h as compared to control reactions in its absence or in the presence of other commercial beta-glucosidase preparations. The high stability (half-life higher than 5 days at 50°C and pH 5.2) and 2–38000 fold higher (as compared with reported beta-glucosidases) activity towards cello-oligosaccharides may account for its performance in supplementation assays. Conclusions The results suggest that beta-glucosidases from yet uncultured bacteria from animal digestomes may be of a potential interest for biotechnological processes related to the effective bio-ethanol production in combination with low dosage of commercial cellulases
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