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Kamp Wilkinson posted an update 1 week, 4 days ago
The responses of pure strains to contaminant (i.e., estrone, E1) exposure have been widely studied. However, few studies about the responses of multispecies microbial aggregates (e.g., periphytic biofilm) to E1 exposure are available. Integrin antagonist In this study, the changes in physiological activity and community composition of periphytic biofilms before and after E1 exposure were investigated. The results showed that periphytic biofilms exhibited high adaptability to E1 exposure at a concentration of 0.5 mg L-1 based on physiological results. The increase in productivity of extracellular polymeric substances (EPS) after exposure to E1 was the main factor preventing association between E1 and microbial cells. The increase in the activity of superoxide dismutase (SOD) and ATP enzyme activity and the change in the co-occurrence pattern of microbial communities (increasing the relative abundance of Xanthomonadaceae and Cryomorphacea) also protected biofilms from E1 exposure. However, exposure to a high concentration of E1 (>10 mg L-1) significantly decreased EPS productivity and metabolic activity due to the excessive accumulation of reactive oxygen species. In addition, the abundance of some sensitive species, such as Pseudanabaenaceae, decreased sharply at this concentration. Overall, this study highlighted the feasibility of periphytic biofilms to adapt to E1 exposure at low concentrations in aquatic environments.This study investigated 324 groundwater samples collected from the southwest plain of Shandong Province during the dry and wet seasons. Groundwater fluoride in the study area and the influencing factors were characterized and discussed using statistical analysis, ion ratios, Piper diagrams, the saturation index (SI) and ArcGIS software. In addition, the risk posed by groundwater fluoride to human health was assessed. The results showed that groundwater in the study area had elevated fluoride concentrations, with average dry and wet season concentrations of 1.15 mg·L-1 and 1.08 mg·L-1, respectively. Groundwater fluoride showed consistent spatial variations during the dry and wet seasons, with a significant regionalization pattern of low concentrations in the east and high concentrations in the west. Groundwater F- was significantly negatively correlated with Ca2+ and positively correlated with pH, HCO3- and Na+. Important factors identified as having an effect on groundwater F- in the study area included the balance of dissolution of fluorite and calcite, the weakly alkaline environment and cation exchange. In addition, hydrochemical types of high-fluoride groundwater in the study area were identified as mainly HCO3-Na and SO4·Cl-Na. The assessment of the risk of high groundwater fluoride to human health showed that children are more at risk compared to adults, with the risk during the dry season exceeding that over the wet season. It is recommended that water quality management in the study area prioritize the formulation of measures to mitigate high concentrations of fluoride in groundwater .Decidualization, which endows the endometrium competency to adopt developing embryo and maintain appropriate milieu for following growth, is a pivotal process for human pregnancy. The delicate collaboration between ovarian steroid hormones estrogen and progesterone governs the process of decidualization and subsequent establishment of embryo implantation. Mycotoxin zearalenone (ZEA) is well known as endocrine disruptor due to its potent estrogenic activity. In this study, we investigated effects of ZEA on decidualization of human endometrial stromal cells. Results indicated that ZEA exhibited its inhibitory action through nuclear translocation of ERα. ZEA exposure led to dampened progress of decidualization, which could be attenuated by estrogen receptor antagonist. Notably, resveratrol (RSV) administration restored impaired decidualization process by induction of anti-oxidative gene glutathione peroxidase 3 (GPX3). This study provides novel insights into the mechanism underlying adverse effects of ZEA in human decidual stromal cells and suggests RSV a potential therapeutic candidate to alleviate ZEA-induced cytotoxicity during decidualization.Currently there is a wide variety of collectors used in mineral processing, the xanthates being the most used in sulfides flotation. Unfortunately, it is known that xanthates are not stable compounds and their decomposition generates carbon disulfide (CS2), a substance that is considered toxic. These aspects have motivated the search for collectors that exhibit superior performance without the health, safety and environmental (HSE) concerns associated with xanthates. In this study, the chemical stability of three xanthates of different alkyl groups (sodium ethyl xanthate (SEX), sodium isopropyl xanthate (SIPX) and potassium amyl xanthate (PAX)) was evaluated by UV/Vis spectroscopy, as a function of pH and time. Similarly, the chemical stability of three chelating collectors was evaluated sodium di-isobutyl dithiophosphinate (SDIBDTPI), benzohydroxamic acid (BHA) and octanohydroxamic acid (OHA). Likewise, the surface tension of their aqueous solutions was measured making use of the Du Noüy method, to determine the critical micelle concentration (CMC). The results showed that the xanthate UV/Vis absorption spectra reflect the presence of a chemical reaction as the pH decreases from 4 to 2.5, which results in the formation of carbon disulfide (CS2). In addition, the generation of CS2 is favored as time elapses and the pH of the solutions decreases from 10 to 6, regardless of the hydrocarbon chain length. Conversely, dithiophosphinate and hydroxamic acids present greater chemical stability, although they form micelles at a certain concentration (CMC), a phenomenon that is not observed with xanthates. By not hydrolyzing, oxidizing, or decomposing into other chemical species, SDIBDTPI, BHA, and OHA may be considered environmentally friendly reagents. In the above context, it is important to promote the adoption of these collectors in mineral processing.Deltamethrin (DLM) is widely used in agriculture and the prevention of human insect-borne diseases. However, the molecular mechanism of DLM induced liver injury remains unclear to date. This study investigated the potential molecular mechanism that DLM induced liver fibrosis in quails. Japanese quails received resveratrol (500 mg/kg) daily with or without DLM (45 mg/kg) exposure for 12 weeks. Histopathology, transmission electron microscopy, biochemical indexes, TUNEL, quantitative real-time PCR, and western blot analysis were performed. DLM exposure induced hepatic steatosis, oxidative stress, inflammation, and apoptosis. Most importantly, the Nrf2/TGF-β1/Smad3 signaling pathway played an important role on DLM-induced liver fibrosis in quails. Interestingly, the addition of resveratrol, an Nrf2 activator, alleviates oxidative stress and inflammation response by activating Nrf2, thereby inhibits the liver fibrosis induced by DLM in quails. Collectively, these findings demonstrate that chronic exposure to DLM induces oxidative stress via the Nrf2 expression inhibition and apoptosis, and then results in liver fibrosis in quails by the activation of NF-κB/TNF-α and TGF-β1/Smad3 signaling pathway.