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us venom on organ contractility was quite complex and seem to derive from a diffuse and nonspecific release of mediators from autonomic and enteric nervous systems. Further investigation of venom action and its isolated toxins can reveal important aspects to deepen our knowledge about the enteric nervous system transmission and the interaction between excitatory and inhibitory mediators as well as the physiological role of Na+ and K+ ion channels in gut motility.Co3O4-SnO2/rice straw biochar (RSBC) was prepared for the first time via calcining oxalate precipitation precursor dispersed on the surface of RSBC and used as a catalyst for activating PMS to degrade sulfisoxazole (SIZ). The results demonstrated that Co3O4-SnO2/RSBC possessed much better catalytic performance than Co3O4, Co3O4-SnO2, Co3O4/RSBC, and SnO2/RSBC, which is ascribed to the synergy of Co3O4, SnO2 and RSBC. Approximately 98% of SIZ (50 mg/L) was decomposed by PMS (1 mmol/L) activated with Co3O4-SnO2/RSBC (0.1 g/L) within 5 min. The optimal degradation efficiency of SIZ was realized at the initial pH 9. Co3O4-SnO2/RSBC also displayed remarkable stability and reusability, and the degradation rate of SIZ maintained over 90% even after the fifth recycle run. The electron paramagnetic resonance (EPR) technique and quenching experiments proved singlet oxygen (1O2) to be the main reactive oxygen species (ROS) responsible for the SIZ decomposition in the Co3O4-SnO2/RSBC/PMS system. On the basis of the characterization analysis, the identification of the ROS and the SIZ degradation products, the possible mechanism and pathways of the SIZ degradation by a combination of PMS and Co3O4-SnO2/RSBC were further proposed. This study provides not only a new insight into non-radical mechanism for the heterogeneous activating PMS over Co3O4-SnO2/RSBC to degrade organic pollutants but also an eco-friendly synthetic route for exploring novel and efficient catalysts.This study compared the effects of five types of inorganic nanoparticles (INPs) on the 17β-estradiol (E2) adsorption to graphene oxide (GO). The results showed that INPs increased the equilibrium time for the adsorption of E2 to GO. Higher Brunauer-Emmett-Teller (BET) surface area of INPs resulted in lower diffusion rate of E2, and thus the adsorption rate constant (k2) calculated from pseudo-second-order kinetic model negatively correlated with the BET surface area of INPs (p = 0.037). In addition, INPs decreased the adsorption amount of E2 to GO, and the inhibition effects declined in the order of Al2O3 &gt; ZnO &gt; TiO2 &gt; SiO2 &gt; Fe2O3. This is determined by the interactions between GO and INPs. The positively charged ZnO and Al2O3 strongly heteroaggregate with GO via electrostatic attraction, and then significantly inhibited E2 adsorption to GO. In contrast, the homoaggregation of GO was superior to its heteroaggregation with negatively charged SiO2 and TiO2, and then lower inhibition of E2 adsorption to GO was induced. Fe2O3 with less negative charge (-8.48 mV) led to the lowest inhibition effect on E2 adsorption to GO because of its preferable homoaggregation. The results were further confirmed by Derjaguin-Landau-Verwey-Overbeek calculation, transmission electron microscopy, and sedimentation experiments. This study revealed how the properties of INPs influence their effects on the adsorption of E2 by GO, and the findings are critical to understand the behavior and fate of GO and pollutants in natural aquatic environment.Background The current knowledge about the effects of vanadium (V) on iron (Fe)-related proteins and Fe homeostasis (which is regulated at the systemic, organelle, and cellular levels) is still insufficient. Objective This fact and our earlier results prompted us to conduct studies with the aim to explain the mechanism of anemia accompanied by a rise in hepatic and splenic Fe deposition in rats receiving sodium metavanadate (SMV) separately and in combination with magnesium sulfate (MS). Results We demonstrated for the first time that SMV (0.125 mg V/mL) administered to rats individually and in conjunction with MS (0.06 mg Mg/mL) for 12 weeks did not cause significant differences in the hepatic hepcidin (Hepc) and hemojuvelin (HJV) concentrations, compared to the control. In comparison with the control, there were no significant changes in the concentration of transferrin receptor 1 (TfR1) in the liver of rats treated with SMV and MS alone (in both cases only a downward trend of 14% and 15% was observed). However, a significant reduction in the hepatic TfR1 level was found in rats receiving SMV and MS simultaneously. In turn, the concentration of transferrin receptor 2 (TfR2) showed an increasing trend in the liver of rats treated with SMV and/or MS. Conclusions The experimental data suggest that the pathomechanism of the SMV-induced anemia is not associated with the effect of V on the concentration of Hepc in the liver, as confirmed by the unaltered hepatic HJV and TfR1 levels. Therefore, further studies are needed in order to check whether anemia that developed in the rats at the SMV administration (a) results from the inhibitory effect of V on erythropoietin (EPO) production, (b) is related to the effect of V on the induction of matriptase-2 (TMPRSS6) expression, or (c) is associated with the influence of this metal on haem synthesis.The present study aims to develop a practical approach for the optimal permeable reactive barrier (PRB) design towards Cr(VI) removal from groundwater. Batch and column experiments were performed to investigate the characteristics of the four proposed reactive materials; nanoscale zero-valent iron (Fe0), bimetallic nanoscale zero-valent iron (Fe0/Cu), activated carbon (AC) and sand/zeolite mixture (S/Z). Kinetic analysis and dynamic modeling of the experimental data were implemented to determine the controlling conditions of the reactive performance of the PRB's materials. The sensitivity index of the design parameters was examined as an indicator of their effect on the reactive responses. Moreover, the Response Surface Methodology (RSM) was considered for optimizing the design variables of the PRB based on the practical factorial analysis. Results revealed that Fe0 and Fe0/Cu showed high performance in Cr(VI) removal, with a slight superiority to Fe0, with final removal efficiency values of 89.7 and 84.1%, rthe optimal conditions regarding the long residency (tR = 22 days) and low cost (b = 0.521 m), with around 95.2% desirability of its optimal solution. Overall, the current study represents a significant contribution and a vital step towards an accurate PRB's design based on previously determined optimal conditions.Recently two-dimensional nanomaterials, such as graphene and molybdenum disulfide (MoS2), have received much attention as adsorbent materials for the effective removal of organic contaminants. MoS2 is attracting attention, not only for its chemical-physical properties, but also for its wide availability in nature as a constituent of molybdenite. The aim of this investigation was to assess the effects of different MoS2 concentrations (5 × 10-1, 5 × 10-2 and 5 × 10-3 mg/ml) on the embryonated eggs of Gallus gallus domesticus, according to Beck method. We evaluated the toxic effect of the MoS2 powder purchased at Sigma-Aldrich indicated as "received" and MoS2 powder treated via mechanical milling indicated as "ball mille". Subsequently, the embryos were sacrificed at different times of embryonic development (11th, 15th and 19th day after incubation) in order to evaluate their embryotoxic and teratogenic effects. The alterations of the embryonic development were studied by morphological and immunohistochemical analysis of the tissues. The results obtained have shown the toxicity of both powders of MoS2 with a high percentage of deaths and growth delays. Moreover, the immunohistochemical analysis performed on several tissue sections showed a strong positivity to the anti-metallothionein1 antibody only for the erythrocytes.Herein is presented a simple and sensible method to determine organic pollutants in water, based on the utilization of silver nanoparticles (AgNPs) loaded in Polyacrylamide (PAAm)/starch hybrid hydrogels combined with surface-enhanced Raman scattering (SERS) spectroscopy. The materials were characterized by swelling degree studies, UV-Visible spectroscopy (UV-Vis), X-ray diffraction (XRD) and scanning electron microscopy (SEM). PAAm/starch hydrogels showed variable swelling capacity, according to the synthetic molar composition. The most promising results were attributed to lower concentrations of starch and crosslink agent (N,N'-methylenebisacrylamide - MBA). Spectroscopic analysis confirmed the formation of AgNPs, by noticing the peak at around 420 nm, due to its surface plasmon resonance (SPR) effect. The results showed that AgNPs were stabilized by hydrogels networks. The average size of the AgNPs was smaller than 100 nm and the size and quantity of nanoparticles were influenced by the molar composition of the hydrogel matrix. The SERS substrate based on the AgNPs-PAAm/starch exhibited reproducibility, stability, and limit of detection (LOD) of phenol in water of 1 × 10-8 M. The average mass of AgNPs-PAAm/starch hydrogels used for each detection analysis was around 10 mg. [https://www.selleckchem.com/products/pf-8380.html see more] The spectra with enhanced intensities were possible due to a large number of hot spots generated on the AgNPs-PAAm/starch hydrogel substrate, which leads to potential use for organic pollutant detection. In addition, there is also the possibility of reusing the hydrogel matrix substrate in other analyzes.Arsenic is a recognized highly toxic contaminant, responsible for numerous human diseases and affecting many millions of people in different parts of the world. Contrarily, curcumin is a natural dietary polyphenolic compound and the main active ingredient in turmeric. Recently it has drawn great attention due to its diverse biological activities, strong antioxidant properties and therapeutic potential against many human ailments. In this study, we aimed to explore the protective effects and the regulatory role of curcumin on arsenic-induced toxicity and gain insights into biomolecular mechanism/s. Arsenic (10 μM) treatment in PC12 cells for 24 h induced cytotoxicity by decreasing cell viability and intracellular glutathione level and increasing lactate dehydrogenase activity and DNA fragmentation. In addition, arsenic caused apoptotic cell death in PC12 cells, which were confirmed from flow cytometry results. Moreover, arsenic (10 μM) treatment significantly down-regulated the inhibition factors of autophagy/apoptosis; mTOR, Akt, Nrf2, ERK1, Bcl-x, Xiap protein expressions, up-regulated the enhanced factors of autophagy/apoptosis; ULK, LC3, p53, Bax, cytochrome c, caspase 9, cleaved caspase 3 proteins and eventually caused autophagic and apoptotic cell death. However, curcumin (2.5 μM) pretreatment with arsenic (10 μM) effectively saves PC12 cells against arsenic-induced cytotoxicity through increasing cell viability, intracellular GSH level and boosting the antioxidant defense system, and limiting the LDH activity and DNA damage. Furthermore, pretreatment of curcumin with arsenic expressively alleviated arsenic-induced toxicity and cell death by reversing the expressions of proteins; mTOR, Akt, Nrf2, ERK1, Bcl-x, Xiap, ULK, LC3, p53, Bax, cytochrome c, caspase 9 and cleaved caspase 3. Our findings indicated that curcumin showed antioxidant properties through the Nrf2 antioxidant signaling pathway and alleviates arsenic-triggered toxicity in PC12 cells by regulating autophagy/apoptosis.