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Biochar is increasingly used as a low-cost and effective adsorbent for heavy metals in wastewater. Herein, biochar pyrolyzed from rice straw was employed as an adsorbent for the removal of Th(IV) from aqueous solutions. The sorption of Th(IV) on biochar was strongly dependent on pH, but independent on ionic strength at pH < 6.4. The inner-sphere complexation dominated the sorption mechanism of Th(IV) on biochar. The competition for Th(IV) between aqueous or surface-adsorbed cations/anions and functional groups of biochar was pivotal for Th(IV) sorption. The thermodynamic data suggested that Th(IV) sorption was a spontaneous and endothermic process. [ABSTRACT FROM AUTHOR]

The role of fulvic acid (FA) in the sorption of Co(II) onto reduced graphene oxide (RGO) and graphene oxide (GO) were investigated using batch equilibrium method and extended X-ray absorption fine structure (EXAFS). The results showed that FA could be adsorbed on both RGO and GO via different interaction mechanisms, and thus exert different roles in Co(II) sorption. The sorption of FA on RGO was mainly controlled by π–π interaction, and the adsorbed FA introduced negative charges and O-bearing functional groups on RGO, facilitating Co(II) sorption due to electrostatic attraction and complexation. Meanwhile, the sorption of FA on GO was mainly governed by polar interactions, and the adsorbed FA can not only introduce new sites for enhanced Co(II) sorption, but also shield the surface of GO and occupy parts of sorption sites, which decreased Co(II) sorption. So, FA had little role in Co(II) sorption onto GO. EXAFS results suggest that O-bearing functional groups of RGO and GO were the main sorption sites for Co(II). Compared to GO, a portion of Co(II) precipitate on RGO surfaces at pH 8.78 due to fewer O-bearing functional groups. The introduction of FA provides lots of sorption sites on RGO, which makes Co(II) be adsorbed on RGO as RGO-FA-Co ternary surface complexes. The results of this work indicated that both RGO and GO exhibited great potential in pollution control applications, even in mixed organic and inorganic pollutants. [ABSTRACT FROM AUTHOR]

In recent years, the fate and transport of graphene oxide (GO) has received considerable attention owing to its inevitable release into the natural ecosystem during production and applications, wherein mineral particles and radionuclides are generally co-presented. This paper aimed to clarify the sorption and co-sorption of Eu(III) and GO onto Mg/Al layered double hydroxides (LDH) using batch and extended X-ray absorption fine structure (EXAFS) studies. The results showed that Eu(III) and GO displayed interactively enhancement roles in their co-sorption on LDH. Eu(III) enhanced GO co-sorption on LDH which was mainly due to the formation of “LDH-Eu(III)-GO” ternary surface complexes (i.e., Eu(III)-bridging). While, GO increased Eu(III) co-sorption on LDH which was primarily due to the formation of “LDH-GO-Eu(III)” ternary surface complexes (i.e., GO-bridging). EXAFS fitting results exhibited that the presence of GO could suppress the formation of outer-sphere complexes of Eu(III) on LDH at low pH values, while inhibit the formation of surface precipitates of Eu(III) on LDH at high pH values. The enhanced co-sorption of Eu(III) and GO on LDH as they co-presented might decrease their mobility in the natural environment. These new findings are important to understand the environmental behavior and impact of GO in real ecosystem, and the natural purification of radionuclides in ecological environments. [ABSTRACT FROM AUTHOR]

Objectives: Interleukin 33 (IL-33) is a crucial inflammatory factor that functions as an alarm signal in endometriosis (EMs). Epithelial-mesenchymal transition (EMT), a process related to inflammatory signals, intracellular reactive oxygen species (ROS) production, and lipid peroxidation, have been proposed as potential mechanisms that contribute to the development and progression of EMs. IL-33 is highly upregulated in the ectopic milieu. Moreover, ectopic endometrial cells constitutively express interleukin-33 receptor ST2 (IL-33R). However, the role of IL-33/ST2 in the EMT of EMs remains largely unknown. In this study, we aimed to mechanistically determine the role of IL-33/ST2 in EMs-associated fibrosis. Materials and methods: We established a non-lethal oxidative stress model to explore the conditions that trigger IL-33 induction. We performed α-smooth muscle actin (α-SMA) protein detection, cell counting kit-8 (CCK-8) assays, and scratch assays to analyze the impact of IL-33 on primary endometrial stromal cells (ESCs) proliferation and invasion. Clinical samples from patients with or without EMs were subjected to immunohistochemical (IHC) and and immunofluorescence(IF) staining to assess the clinical relevance of IL-33 receptor ST2 and EMT-related proteins. Furthermore, we used the ectopic human endometrial epithelial cell line 12Z and normal human epithelial cell line EEC to evaluate the effects of IL-33 on Wnt/β-catenin signaling. The effect of IL-33 on EMT-associated fibrosis was validated in vivo by intraperitoneal injections of IL-33 and antiST2. Results: We observed that ectopic milieu, characterized by ROS, TGF-β1, and high level of estrogen, triggers the secretion of IL-33 from ectopic ESCs. Ectopic endometrial lesions exhibited higher level of fibrotic characteristics and ST2 expression than that in the normal endometrium. Exogenous recombinant human (rhIL-33) enhanced ESC migration and survival. Similarly, 12Z cells displayed a higher degree of EMT characteristics with elevated expression of CCN4 and Fra-1, downstream target genes of the WNT/β-catenin pathway, than that observed in EECs. Conversely, blocking IL-33 with neutralizing antibodies, knocking down ST2 or β-catenin with siRNA, and β-catenin dephosphorylation abolished its effects on EMT promotion. In vivo validation demonstrated that IL-33 significantly promotes EMs-related fibrosis through the activation of Wnt/β-catenin signaling. Conclusion: Our data strongly support the vital role of the IL-33/ST2 pathway in EMs-associated fibrosis and emphasize the importance of the EMT in the pathophysiology of fibrosis. Targeting the IL-33/ST2/Wnt/β-catenin axis may hold promise as a feasible therapeutic approach for controlling fibrosis in EMs. [ABSTRACT FROM AUTHOR]

• Porous hexagonal boron nitride (p-BN) was employed for Ni(II) scavenging. • The p-BN displayed a high removal rate to Ni(II). • The p-BN exhibited an adsorption capacity to Ni(II). • Interaction between hydroxyl-O and electron-deficient B is the main mechanism. Intending to remove Ni(II) from wastewater, porous p-BN was employed to recovery Ni(II) by batch and X-ray photoelectron spectroscopy technique. The performances and mechanism of p-BN for Ni(II) sorption had been studied by diverse characterization technologies. The kinetic data was calculated to conform a pseudo-second-order model, and isotherm data fitted to a Freundlich equation. We obtained a high removal rate and a high adsorption capacity. A possible mechanism can be expressed from XPS results. The surface of p-BN is B OH/B NH 2 enriched and exhibits a weak alkalinity. When p-BN contact with Ni(II) solution, the hydroxide ions releases from the surface while there is a formation of B O⋯Ni; the small group of B O⋯Ni is acting with hydroxide ions, thereby forming B O⋯Ni(OH) 2 and continuously adsorbs Ni(II) to form B O⋯Ni(OH)ONi(OH) like as precipitated nucleus. Then, due to the interaction of hydroxyl-O with electron-deficient B, the veil-like Ni(OH) 2 generated from precipitated nucleus evenly attaches to p-BN. The bonding state of Ni(II) on p-BN by XPS spectra revealed that the process of adsorbing Ni(II) onto p-BN was chemisorption through the formation of Ni(OH) 2 and the interaction between hydroxyl-O and electron-deficient B. The analyses implied that p-BN is a promising candidate for recovery of Ni(II) from wastewater. [ABSTRACT FROM AUTHOR]

Background: As a dual-function metabolite, succinate has emerged in cell function and plays a key signaling role in linking mitochondrial function to other cellular functions. Succinate accumulation in the cytoplasm is commonly associated with hypoxia in the microenvironment and immune cell activation. Extracellular succinate released into the microenvironment is considered an inflammatory alarm that can be sensed by its membrane receptor SUCNR1, which boosts proinflammatory responses and acts akin to classical hormones and cytokines. Succinate plays an important role in the development of inflammatory diseases. Whether succinate facilitates the progression of endometriosis (EMs), characterized by chronic inflammation and peritoneal adhesion, is worth exploring. Objective: We mimicked the ectopic milieu in vitro and in vivo to evaluate the main source and potential role of succinate in endometriosis. We assessed the molecular and functional effects of succinate on macrophages and peritoneal mesothelial cells in peritoneal cavity. The effect of succinate/SUCNR1 signaling on ectopic endometrial stromal cells (ESCs) was further explored in this study. Methods: In this study, we used targeted organic acid metabolomics analysis and in vitro assays to assess the potential accumulation of succinate in the peritoneal fluid of EMs patients. We examined its correlation with disease severity, Visual Analogue Scale, and the Endometriosis Fertility Index. Flow cytometry, enzyme linked immunosorbent assay, western blot assay, quantitative real-time PCR, and other molecular biology techniques were used to explore the potential mechanisms. Results: By mimicking the ectopic milieu, we constructed an in vitro co-culture system and found that M1 polarized macrophages and that the peritoneal mesothelial cell line (HMrSV5) mainly released succinate into their microenvironment and activated the succinate receptor (SUCNR1) signal, which further polarized the macrophages and significantly enhanced the invasive survival of ESCs, and the adhesion to the peritoneum. We further investigated the pathological effects of extracellular succinate in vivo using a xenograft mouse models of endometriosis. Conclusions: Succinate-SUCNR1 signaling facilitates the creation of inflammatory cells and plays a vital role in EMs progression and peritoneal adhesion. Our work on the molecular mechanisms underlying succinate accumulation and function will help elucidate the phenotypic mysteries of pain and infertility in EMs. BkiB34NQBDvkGHWZYD1GB2 Video Abstract [ABSTRACT FROM AUTHOR]

Succinate is an important intermediate of the tricarboxylic acid cycle. Recently discovered roles of succinate demonstrate its involvement in immunity and cancer biology; however, the precise underlying mechanisms of its involvement in these additional roles remain to be determined. In the present study, succinate dehydrogenase (SDH) B was decreased in uterine endometrial cancer cells (UECC) under negative regulation of estrogen. This decrease was the result of lower expression levels of ubiquitin C (UBC), which was associated with the activation of peroxisome proliferator-activated receptor gamma and specificity protein 1. The decreased levels of SDHB resulted in the accumulation of succinate in UECC, and thus, a decrease in the production of fumaric acid. Succinate downregulated voltage-gated potassium channel subfamily Q member 1 (KCNQ1) levels by activating serum/glucocorticoid regulated kinase 1 and promoted the growth of UECC in vitro and in vivo. Treatment with melatonin restricted estrogen/UBC/SDHB-induced succinate accumulation and upregulated expression of KCNQ1 and reduced the succinate-mediated growth of UECC in vitro and in vivo. Furthermore, overexpression of melatonin receptor 1B amplified the inhibitory effects of melatonin on succinate-mediated UECC growth. Together, the data in the present study suggest that melatonin suppresses UECC progression by inhibiting estrogen/UBC/SDHB-induced succinate accumulation. The present study provides a scientific basis for potential therapeutic strategies and targets in UEC, particularly for patients with abnormally low levels of SDHB. [ABSTRACT FROM AUTHOR]

A novel nanocomposite, i.e., molybdenum disulfide nanosheets embellished nanoiron (MoS 2 /NZVI), was synthesized by a modified NaBH 4 reduction procedure, and used for the effective capture of Cr(VI) in water. The characteristic analysis implied that MoS 2 could hinder the aggregation of NZVI. The batch experiments showed that Cr(VI) capture by NZVI/MoS 2 (91.7%) was obviously higher than that of either bare NZVI (62.6%) or MoS 2 (27.05%). The kinetics of Cr(VI) capture can be well described by the pseudo-second-order model. The effects of pH and natural organic matters were also evaluated. Solution pH was found to be significant to Cr(VI) capture, acidic environment (pH 5.0 and 6.0) was more suitable for Cr(VI) capture. However, natural organic matters demonstrated negative effects on Cr(VI) capture. The capture capacity of NZVI/MoS 2 nanocomposite decreased from 126.42 mg/g to 118.48 and 121.07 mg/g when humic acid and fumic acid were present in the solution. X-ray photoelectron spectroscopy analysis of the mechanism indicated that adsorption, reduction, and precipitation were involved in the capture process. The results suggested that the NZVI/MoS 2 nanocomposite may be a potential candidate for the capture of Cr(VI) from wastewater. [ABSTRACT FROM AUTHOR]

Aim: Cisplatin‐based chemotherapy is the first‐line treatment for ovarian cancer. However, acquired resistance to cisplatin treatment or serious side effects often occurs in ovarian cancer, and thus, there is an urgent need for effective and combined therapies to overcome such obstacles. In the present study, we aimed to uncover synergistic effects between erastin and cisplatin (CDDP) in inhibiting ovarian cancer cell growth by inducing ferroptosis in vitro and in vivo. Methods: We performed a CCK‐8 assay to detect cell viability in response to erastin alone or in combination with cisplatin and provided further confirmation by western blotting analysis. Transmission electron microscopy and flow cytometry analysis were used to depict the characteristics of ferroptosis. In addition, an ovarian cancer tumor xenograft was built to verify the effects in vivo. Results: CDDP induced multiple modes of cell death‐including ferroptosis in ovarian cancer cell lines. Mechanistically, erastin triggered ferroptosis and increased the levels of reactive oxygen species (ROS) so as to augment the cytotoxic effect of cisplatin. Combination therapy based on CDDP and erastin appeared to maximize the therapeutic effects while minimizing side effects in ovarian cancer both in vitro and in vivo. Conclusion: Collectively, our results indicate that erastin works synergistically with cisplatin to inhibit ovarian cancer cell growth, which may be manipulated by a ROS‐mediated mechanism that enhances cisplatin therapy, and offers a novel strategy for overcoming cisplatin therapy resistance. [ABSTRACT FROM AUTHOR]

Magnetic sepiolite was synthesized by chemical precipitation of Fe and Fe at sepiolite suspension. Removal kinetics of U(VI) on sepiolite and magnetic sepiolite can be well fitted by pseudo-second-order and pseudo-first-order kinetic models, respectively. At pH < 5.0, U(VI) removal on sepiolite significantly decreased with increasing ionic strength, whereas U(VI) removal on magnetic sepiolite was independent of ionic strength. The maximum removal capacity of sepiolite and magnetic sepiolite at pH 5.0 and 298 K calculated from Langmuir model were 28.17 and 74.63 mg/g, respectively. XANES spectra suggested that U(VI) was partly reduced to U(IV) at long-term conditions. [ABSTRACT FROM AUTHOR]

In the present study, titanate nanotubes (denoted as TNTs) synthesized through a simple hydrothermal approach was applied for the decontamination of Zn(II) from aqueous solution. Batch experimental results showed that the removal kinetics process was fast and reached equilibrium after 60 min. The sorption of Zn(II) on TNTs was strongly dependent on pH and ionic strength at pH < 6.0, while independent of ionic strength at pH > 6.0. Based on Langmuir model fit, the maximum sorption capacity of Zn(II) at pH 5.5 and 293 K was calculated to be 139.44 mg/g, being higher than a series of currently reported adsorbents. TNTs also exhibited a favorable recycling performance for the removal of Zn(II). According to the desorption experiments, surface complexation modeling, X-ray diffraction (XRD) and extended X-ray absorption fine structure (EXAFS) analysis, cation exchange and/or outer-sphere surface complexation were the predominant removal mechanisms of Zn(II) at lower pH, while inner-sphere surface complexation and/or precipitation were the main driving forces at higher pH. The experimental findings herein demonstrated the application potentiality of TNTs for the highly efficient treatment of Zn(II)-bearing wastewaters. [ABSTRACT FROM AUTHOR]

• Novel composite material of g-C 3 N 4 decorated FeS was designed and prepared. • The adsorption capacity for U(VI) was 917.1 mg/g at pH = 6.0. • The adsorption isotherm for U(VI) was described by the Freundlich model. In this study, a novel graphitic carbon nitride decorated nanoscale FeS composite (g-C 3 N 4 /FeS) was prepared and performed for the removal of U(VI) in aqueous system. Results revealed that g-C 3 N 4 /FeS had excellent adsorbability, which can reach 917.1 mg/g at 303 K. In addition, the effects of pH, adsorbent dose, contact time and initial U(VI) concentration were investigated by batch experiments. Experimental results indicated the removal of U(VI) on g-C 3 N 4 /FeS was strongly dependent on pH, and the adsorption capacity reached the maximum at pH = 6.0. Kinetics studies under different conditions indicated the removal of U(VI) on g-C 3 N 4 /FeS fitted the pseudo-second-order model well. Furthermore, the adsorption isotherms of U(VI) on g-C 3 N 4 /FeS fitted with Freundlich models well. These results demonstrated that g-C 3 N 4 /FeS could be the promising alternative material for environmental remediation. [ABSTRACT FROM AUTHOR]

In order to investigate scavenging mechanism of rare earth metal ions in water by graphene oxide (GO), effects of ion concentration and adsorption time on the adsorption of the metal ions, such as La(III) and Nd(II), were surveyed systematically. The molecular structure, surface functional groups and morphology of the GO before and after adsorbing the rare earth metal ions were characterized by Raman spectroscopy, FITR, and XPS. To shed more light on the sorption mechanism, static density functional theory (DFT) calculation was introduced to portray the molecular-scale interaction between GO and the rare earth metal ions. The results indicated that the GO showed high adsorbing capacities of 105.5 mg/g for La(III) and 99.1 mg/g for Nd(II) at 20 °C and pH 5.5, respectively. The adsorption reached equilibriums within 120 min and the adsorption kinetics of La(III) and Nd(II) followed the pseudo-first-order kinetic model well. The Freundlich and Langmuir models were used to simulate the adsorption isotherms of the rare earth metal ions, demonstrating that the adsorption fitted well with Langmuir model. Experimental results of this work demonstrated that GO was a promising economical material for the removal of La(III) and Nd(II) from aqueous solutions. Unlabelled Image • GO has good removal ability for La(III) and Nd(II) from water. • The adsorption processes of La(III) and Nd(II) on GO are both fitted well by pseudo-first-order kinetic model. • The adsorption of La(III) and Nd(II) on GO both fit well with Langmuir model. [ABSTRACT FROM AUTHOR]