Selenium (Se) plays a protective role in aflatoxin B1 (AFB1)–induced splenic immunotoxicity in chicks.
This study was designed to reveal the underlying mechanism of Se-mediated protection against ...AFB1-induced splenic injury in broilers.
Four groups of 1-d-old Cobb male broilers (n = 5 cages/diet, 6 chicks/cage) were arranged in a 3-wk 2 × 2 factorial design trial whereby they were fed an Se-deficient, corn- and soy-based diet base diet (BD), 36 μg Se/kg, BD plus 1.0 mg AFB1/kg, BD plus 0.3 mg Se/kg, or BD plus 1.0 mg AFB1/kg and 0.3 mg Se/kg (as 2-hydroxy-4-methylselenobutanoic acid). Serum and spleen were collected at week 3 to assay for cytokines, histology, redox status, selected inflammation- and apoptosis-related genes and proteins, and the selenogenome.
Dietary AFB1 induced growth retardation and spleen injury, decreasing (P < 0.05) body weight gain, feed intake, feed conversion efficiency, and serum interleukin-1β by 17.8–98.1% and increasing (P < 0.05) the spleen index and serum interleukin-6 by 37.6–113%. It also reduced the splenic lymphocyte number, the white pulp region, and histiocyte proliferation in Se-adequate groups. However, Se deficiency aggravated (P < 0.05) these AFB1-induced alterations by 16.2–103%. Moreover, Se deficiency decreased (P < 0.05) splenic glutathione peroxidase (GPX) activity and glutathione-S transferase and glutathione concentrations by 35.6–89.4% in AFB1-exposed groups. Furthermore, Se deficiency upregulated (P < 0.05) the apoptotic (Caspase 3 and Caspase 9) and antimicrobial (β defensin 1 and 2) genes, but downregulated (P < 0.05) antiapoptotic (B-cell lymphoma 2) and inflammatory (E3 ubiquitin-protein ligase CBL-B) genes at the mRNA and/or protein level in AFB1 supplementation groups. Additionally, Se deficiency downregulated (P < 0.05) GPX3, thioredoxin reductase 1 (TXNRD 1), GPX4, and selenoprotein (SELENO) S, and upregulated (P < 0.05) SELENOT and SELENOU in spleen in AFB1 administered groups.
Dietary Se deficiency exacerbated AFB1-induced spleen injury in chicks, partially through the regulation of oxidative stress, inflammatory and apoptotic signaling, and 6 selenoproteins.
The co-contamination of cereals, grains, crops, and animal feeds by mycotoxins is a universal problem. Humans and animals are exposed to several mycotoxins simultaneously as evidenced by extensive ...studies on this topic. Yet, most studies have addressed the effects of mycotoxins individually. Aflatoxin B1 and ochratoxin A can induce immunotoxicity. However, it remains unclear whether a combination of these mycotoxins aggravates immunotoxicity and the potential mechanism underlying this effect. In this study, we used the cell line 3D4/21, swine alveolus macrophages and innate immune cell. The results showed that the percentage of cell inhibition, annexin V/PI-positive rates, and the expression of pro-inflammatory cytokines (tumor necrosis factor alpha and interleukin-6) significantly increased and the release of lactate dehydrogenase and phagocytotic index were significantly decreased at different concentrations of aflatoxin B1 and ochratoxin A combination when compared with control. The combination of aflatoxin B1 and ochratoxin A significantly decreased the production of GSH and increased reactive oxygen species level. However, N-acetylcysteine suppressed the oxidative stress and alleviated the immunotoxicity induced by the combination. The combination of aflatoxin B1 and ochratoxin A markedly enhanced the degradation of IκBa, the phosphorylation of nuclear factor kappa B (p65), and the translocation of activated nuclear factor kappa B (NF-κB) into the nuclei as demonstrated by western blotting and confocal laser scanning microscopy. These effects could be reversed by BAY 11-7082, a specific inhibitor of NF-κB. Taken together, a combination of aflatoxin B1 and ochratoxin A could aggravate immunotoxicity by activating the NF-κB signaling pathway.
•The combination of AFB1 and OTA aggravated immunotoxicity in 3D4/21 cells.•The combination aggravated oxidative stress, IkBa degradation and NF-κB phosphorylation and NF-κB translocation into nucleus.•NAC reversed the immunotoxicity, oxidative stress induced by the combination of AFB1 and OTA.•The inhibitor of NF-κB alleviated the immunotoxicity induced by the combination of AFB1 and OTA.•The combination of AFB1 and OTA aggravated immunotoxicity through NF-kB signaling pathways.
•Thermodynamic modeling for high temperature chemical vapor deposition of SiC was suggested.•Synthesis of α-SiC from various sources including organosilicon compounds was proposed.•The suggested ...thermodynamic conditions were verified with experiments.•Compared to TMS, MTS was found to provide wider process conditions.
In this study, we thermodynamically reviewed the suitable growth process conditions of α-SiC in the Si-C-H system using tetramethylsilane (TMS) and in the Si-C-H-Cl system using methyltrichlorosilane (MTS). In the Si-C-H-Cl system, pure solid SiC was obtained at high temperatures under a larger range of hydrogen dilution ratios than that tolerated in the Si-C-H system. X-ray diffraction and micro-Raman analysis of the products obtained at 1900, 2000, and 2100 °C showed that the α-SiC becomes more dominant with increasing temperature in the Si-C-H-Cl system. While TMS was unsuitable for high temperature processing due to its high C/Si ratio, MTS was found to be appropriate for growing α-SiC crystals at high temperatures under a range of conditions. These results indicate that a novel method to grow α-SiC single crystals through HTCVD using MTS as a precursor could be established.
In the film Rashomon, four witnesses describe seemingly contradictory views of one event. In a recent analogy, an interaction between the master mitotic regulator cyclin B1 and the spindle checkpoint ...component Mad1 was independently described by three groups who propose strikingly different functions for this interaction. Here, we summarize their findings and present a perspective on reconciling the different views.
The cover image is based on the Short Communication Determination of aflatoxin B1 by biomass derived porous carbon modified electrode with molecularly imprinted polymer by Longyi Chen et al., DOI: ...10.1002/elan.202200371.
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•Bi-channel SERS-based LFIA strip for simultaneous detection of AFB1 and ZEN.•Magnetic Fe3O4@PEI/AuMBA@Ag-MBA as the active SERS tags.•Magnetic enrichment significantly increased the ...sensitivity.•High specificity and satisfactory recoveries for AFB1 and ZEN.•Short detection time (20 min) suitable for on-site detection.
Aflatoxin B1 (AFB1) and zearalenone (ZEN) are two mycotoxins that often co-occur in corn. A surface-enhanced Raman scattering-based lateral flow immunoassay (SERS-LFIA) that can simultaneously detect AFB1 and ZEN in corn samples was developed employing the core-interlayer-satellite magnetic nanocomposites (Fe3O4@PEI/AuMBA@AgMBA) as dual-functional SERS tags. Under the optimal conditions, the detection ranges of AFB1 and ZEN in corn samples were 0.1–10 μg/kg and 4–400 μg/kg, respectively. Moreover, the test results for two mycotoxins in contaminated corn samples employing the suggested SERS-LFIA was in line with those of the HPLC technique. In view of its satisfactory sensitivity, accuracy, precision and short testing time (20 min), the developed system has a promising application prospect in the on-site simultaneous detection of AFB1 and ZEN.
•The role of Y2O3 and Al2O3 in Si3N4 whiskers formation was analyzed and determined.•Introduction Al2O3 accelerates grain growth while reduces L/D of whiskers.•A method to obtain Si3N4 whiskers with ...high L/D under mild condition was proposed.
β-Si3N4 whiskers were synthesized by heat treatment of α-Si3N4 and Y2O3 mixed powder, and different content of Al2O3 powder was introduced to adjust the synthesis condition and L/D. Introducing Al2O3 significantly accelerated the phase transformation from α-Si3N4 to β-Si3N4. The phase transformation can be completed at 1650 °C by introducing only 0.3 wt% Al2O3, and the phase transformation temperature was reduced by about 100 °C after 1.8 wt% Al2O3 was introduced. Y2O3 orients β-Si3N4 grain growth, while the role of Al2O3 is to reduce liquid viscosity, promote mass transfer, and accelerate grain growth. Introducing a small amount of Al2O3 and appropriately extending the holding time at a lower treatment temperature has been proven to be an effective method to obtain β-Si3N4 whiskers with higher length and diameter ratio (L/D) under mild conditions. High purity β-Si3N4 whiskers (99 wt%) were proved to be synthesized at low temperature (1650 °C) without pickling.
Aflatoxin B1 (AFB1) is a widespread mycotoxin in food and feed. Although the liver is the main target organ of AFB1, the intestine is the first exposure organ to AFB1. However, the mechanism by which ...AFB1 induced intestinal barrier dysfunction via regulating the farnesoid X receptor (FXR)-mediated myosin light chain kinase (MLCK) signaling pathway has rarely been studied. In vivo, AFB1 exposure significantly decreased the small intestine length and increased the intestinal permeability. Meanwhile, AFB1 exposure markedly suppressed the protein expressions of FXR, ZO-1, occludin, and claudin-1 and enhanced the protein expression of MLCK. In vitro, AFB1 exposure induced intestinal barrier dysfunction by the elevation in the FITC-Dextran 4 kDa flux and inhibition in the transepithelial electrical resistance in a dose-dependent manner. In addition, AFB1 exposure downregulated the mRNA and protein expressions of FXR, ZO-1, occludin, and claudin-1, redistributed the ZO-1 protein, and enhanced the protein expressions of MLCK and p-MLC. However, fexaramine (Fex, FXR agonist) pretreatment markedly reversed the AFB1-induced FXR activity reduction, MLCK protein activation, and intestinal barrier impairment in vitro and in vivo. Moreover, pretreatment with the inhibition of MLCK with ML-7 significantly alleviated the AFB1-induced intestinal barrier dysfunction and tight junction disruption in vitro. In conclusion, AFB1 induced intestinal barrier impairment via regulating the FXR-mediated MLCK signaling pathway in vitro and in vivo and provided novel insights to prevent mycotoxin poisoning in the intestine.
•Aluminate concentration affects desilication product precipitation kinetics and phase composition.•Particle size increases with decreasing aluminate concentration.•Zeolite LTN forms at low aluminate ...concentration and results in large size increases up to 60 µm.•UV-Raman can discern the LTN phase from zeolite LTA and sodalite.
It remains a grand challenge in the treatment of bauxite residue to physically separate zeolite (also known as the DeSilication Product, DSP) from other unleached mineral phases owing to their fine sizes, typically less than 2 µm in diameter. In this study, the effect of aluminate concentration on DSP phase transformation was investigated from synthetic NaOH-NaAl(OH)4-Na2SiO3-H2O solution at 90 °C. The results show how at relatively low aluminate concentrations of 0.125 and 0.25 M NaAl(OH)4(aq), larger zeolite crystals of up to 60 µm in diameter are formed during homogenous precipitation from aqueous solution. The precipitation process involves the conversion of zeolite LTA to sodalite via the formation of an intermediate phase, octahedral LTN. Initial amorphous solids precipitate as aggregates in which cubic zeolite LTA nucleation occurs. As the reaction proceeds, truncated octahedral LTN appears with the cubic zeolite LTA and finally sodalite crystallizes on the LTA-LTN aggregates resulting in coarsened particles.
To develop a B1+ mapping during the transient phase of balanced steady state free precession (bSSFP) imaging which can be used for subsequent B1+ inhomogeneity compensation.
Two images with different ...flip angles (FA) are acquired using single-shot spiral technique during the transient phase of bSSFP with three consecutive RF pulses and balanced gradients. Under the assumptions that the transmit (B1+) field varies slowly in spatial domain and T1 and T2 relaxation effects are negligible during 2·TR, B1+ was estimated using the two magnitude images and bSSFP data was sequentially acquired. B1+ estimation error due to the assumptions and other factors such as FA and off-resonance were assessed using Bloch simulation. Phantom and in vivo experiments were performed with α-2α-3α scheme.
The simulation results indicated that the proposed method was less sensitive to T1 relaxation and B1+ mapping FA (α) of approximately 60° produced minimum estimation error. The B1+-induced intensity variation was reduced with the proposed method in the phantom experiment. For both the phantom and in vivo experiments, the estimated B1+ map showed comparable to the conventional B1+ map using spin-echo DAM.
B1+ map was estimated during the transient phase of bSSFP and subsequently compensated bSSFP images. There was no scan time increment and hence the technique can be used in a prescan manner for B1+ mapping or shimming.
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