Disclosing the intrinsic nature of efficient removal of antibiotics in N/S dual-doped porous carbon-based materials: The manipulation of internal electric field

N/S co-doping has emerged as a prevailing strategy for carbon-based adsorbents to facilitate the antibiotic removal efficiency. Nevertheless, the underlying interplay among N, S, and their adjacent vacancy defects remains overlooked. Herein, we present a novel in situ strategy for fabricating pyridinic-N dominated and S dual-doped porous carbon adsorbent with rich vacancy defects (VNSC). The experimental results revealed that N (acting as the electron donor) and S (acting as the electron acceptor) form an internal electric field (IEF), with a stronger IEF generated between pyridinic-N and S, while their adjacent vacancy defects activate carbon π electrons, thus enhancing the charge transfer of the IEF. Density functional theory (DFT) calculations further demonstrated that the rich charge transfer in the IEF facilitated the π-π electron donor-acceptor (EDA) interaction between VNSC and tetracycline (TC) as well as norfloxacin (NOR), and thus is the key to adsorption performance of VNSC. Consequently, VNSC exhibited high adsorption capacities toward TC (573.1 mg g-1) and NOR (517.0 mg g-1), and its potential for environmental applications was demonstrated by interference, environmentally relevant concentrations, fixed-bed column, and regeneration tests. This work discloses the natures of adsorption capacity for N/S dual-doped carbon-based materials for antibiotics.

A real-world disproportionality analysis of FDA adverse event reporting system events for ibuprofen

INTRODUCTION

Ibuprofen is commonly used as an over-the-counter (OTC) antipyretic and analgesic. As the frequency of its use increases, there has been a corresponding increase in reports of associated adverse events (AEs). However, these events have not been systematically reported in the literature. Meanwhile, the importance of effective pharmacovigilance in evaluating the benefits and risks of drugs is being recognized.

METHODS

Data were obtained indirectly from FAERS using the OpenVigil 2 database, lexically mapped using software such as MySQL, Microsoft Excel, and the R language, and then subjected to four more rigorous algorithms to detect risk signals associated with ibuprofen AEs.

RESULTS

By analyzing data from the past 18 years, 878 ibuprofen-related AEs were identified as primary AEs. Notably, unexpected reproductive system and breast disorders were observed as important system organ classes (SOC) associated with ibuprofen. Among the 651 preferred terms (PTs) that simultaneously satisfied the four arithmetic methods, we propose renal tubular acidosis and lip edema as new signals for AEs of ibuprofen.

CONCLUSION

The study explores the important and valuable potential AEs and ADRs of ibuprofen at the SOC and PT levels, respectively. To provide a reference for decision-making for ibuprofen to promote rational clinical dosing.

Development and trends of constructed wetland substrates over the past 30 years: a literature visualization analysis based on CiteSpace

Constructed wetland substrates (CWSs) have received considerable attention owing to their importance in adsorbing and degrading pollutants, providing growth attachment points for microorganisms, and supporting wetland plants. There are differences in the configurations and functions of constructed wetlands (CWs) for treating different water bodies and sewage, resulting in a wide variety of substrates. Research on the application and mechanism of CWSs is not sufficiently systematic. Therefore, the current research advancements and hotspots must be identified. Hence, we used CiteSpace to analyze 1955 English publications from the core collection database of the Web of Science to assess the current state of the CWS research field. Based on the cooperative network analysis, the roles of various countries, institutions, and authors in research on CWSs were reviewed. Keyword co-occurrence and cluster analyses were used to discuss the transformation of CWSs from removing traditional pollutants to emerging pollutants and the transition from incorporating natural substrates to artificial substrates. Finally, we underscored the need for more emphasis to be placed on the collocation and application of the CWSs at different latitudes. Furthermore, the substrate micro-interface process and its effects on the interaction patterns of pollutants and microorganisms should be thoroughly investigated to provide theoretical guidance for the development of wetland applications and mechanisms.

Effects of disturbance modes and carbon sources on the physiological traits and nutrient removal performance of microalgae (S. obliquus) for treating low C/N ratio wastewater

Wastewater treatment with microalgae is an ecologically sustainable process. In this study, the growth characteristics, nutrient removal, and spectral changes of dissolved organic matter (DOM) in microalgae bioreactors were investigated for treating low C/N ratio wastewater under different disturbance modes (agitation and aeration) and carbon sources (sucrose and humic acid). The results showed that the biomass and chlorophyll-a contents of Scenedesmus obliquus in the aeration condition (725.32-811.16 × 104 cells mL-1, 1.58-1.69 mg L-1) were higher than those in the agitation condition (426.06-465.14 × 104 cells mL-1, 1.48-1.61 mg L-1). The better removal of nutrients (TN, 29.62-36.39 mg L-1, TP, 1.84-2.30 mg L-1) by microalgae in sucrose-containing wastewater under agitation conditions occurred on the second day, with removal efficiencies of 21.33-30.67% and 44.84-58.51%, respectively; while it was on the fifth day both in sucrose and humic acid-containing wastewater under aeration conditions (TN, 19.56-31.20 mg L-1, TP, 0.26-0.30 mg L-1), with removal efficiencies of 13.92-46.75% and 88.36-90.50%, respectively. The wastewater DOM primarily consisted of humic-like substances under agitation and aeration conditions characterized by high levels of aromaticity, molecular weight and humification. Furthermore, the aromatization and humification properties of DOM in humic acid wastewater were higher than those in sucrose wastewater, which was corresponding with the lower removal and availability of pollutants by algae. Microalgae showed good biomass accumulation and nutrients removal at incubation time of 2 days (agitation condition) and 5 days (aeration condition), respectively. Consequently, a technical reference is provided for the microalgae coupled with other treatment processes.

Pyridinium-Based Strategy for a Bioorthogonal Conjugation-Assisted Purification Method for Profiling Cell Surface Proteome

Cell surface proteins (CSPs) are valuable targets for therapeutic agents, but achieving highly selective CSP enrichment in cellular physiology remains a technical challenge. To address this challenge, we propose a newly developed sulfo-pyridinium ester (SPE) cross-linking probe, followed by two-step imaging and enrichment. The SPE probe showed higher efficiency in labeling proteins than similar NHS esters at the level of cell lysates and demonstrated specificity for Lys in competitive experiments. More importantly, this probe could selectively label the cell membranes in cell imaging with only negligible labeling of the intracellular compartment. Moreover, we successfully performed this strategy on MCF-7 live cells to label 425 unique CSPs from 1162 labeled proteins. Finally, we employed our probe to label the CSPs of insulin-cultured MCF-7, revealing several cell surface targets of key functional biomarkers and insulin-associated pathogenesis. The above results demonstrate that the SPE method provides a promising tool for the selective labeling of cell surface proteins and monitoring transient cell surface events.

Development of Lysine Crotonyl-Mimic Probe to Covalently Identify H3K27Cr Interacting Proteins

Histone lysine crotonylation (Kcr) is one newly discovered acylation modification and regulates numerous pathophysiological processes. The binding affinity between Kcr and its interacting proteins is generally weak, which makes it difficult to effectively identify Kcr-interacting partners. Changing the amide of crotonyl to an ester increased reactivity with proximal cysteines and retained specificity for Kcr antibody. The probe "H3g27Cr" was designed by incorporating the ester functionality into a H3K27 peptide. Using this probe, multiple Kcr-interacting partners including STAT3 were successfully identified, and this has not been reported previously. Further experiments suggested that STAT3 possibly could form complexes with Histone deacetylase HDACs to downregulate the acetylation and crotonylation of Histone H3K27. Our unique design provided intriguing tools to further explore Kcr-interacting proteins and elucidate their working mechanisms.

Association of triglyceride-glucose index with coronary severity and mortality in patients on dialysis with coronary artery disease

BACKGROUND

The triglyceride-glucose (TyG) index is validated as a reliable biomarker of insulin resistance and an independent predictor of cardiovascular prognosis. However, the prognostic value of the TyG index in patients on dialysis with coronary artery disease (CAD) remained unexplored. This study aimed to determine the association between the TyG index and CAD severity and mortality in these patients.

METHODS

A total of 1061 dialysis patients with CAD were enrolled in this multi-center cohort study from January 2015 to June 2021. The extent and severity of CAD were evaluated using the multivessel disease and Gensini score (GS). Patients were followed up for all-cause death and cardiovascular death.

RESULTS

The multivariable logistic regression model indicated that the TyG index was significantly associated with multivessel disease (odds ratio [OR] 1.51, 95% confidence interval [CI] 1.18-1.94, P = 0.001), and high GS (OR 1.33, 95% CI 1.10-1.61, P = 0.003). After adjusting for baseline risk factors, the hazards of all-cause death and cardiovascular death were 1.23 (95% CI 1.06-1.43, P = 0.007), and 1.33 (95% CI 1.11-1.59, P = 0.002), independent of CAD severity. Restricted cubic spline analysis identified a dose-response association between the TyG index and both CAD severity and mortality (all P for nonlinearity > 0.05). When modeling the TyG index as a categorical variable, these independent associations remained. Subgroup analyses did not substantially modify the results. Furthermore, incorporating the TyG index into the existing risk prediction model improved the predictive accuracy for all-cause death and cardiovascular death, as evaluated by C-statistic, continuous net reclassification improvement, and integrated discrimination improvement.

CONCLUSIONS

In patients on dialysis with CAD, the TyG index was significantly associated with more severe CAD as well as mortality. These results highlight the clinical importance of the TyG index for assessing CAD severity and risk stratification in patients on dialysis with CAD.

Bioorthogonal Fluoride-Responsive Azide and Alkynyl Pyridinium Click Cycloaddition in Vitro and in Live Cells

The copper-free azide-alkyne cycloaddition was broadly applied in numerous research fields. Herein, we report a facile Cu-free click reaction utilizing fluoride-responsive azide and alkynyl pyridinium cycloaddition at ambient temperatures in aqueous media. The reactivity of alkynyl pyridinium was successfully masked by a silyl-protecting group at the alkyne group, and the deprotection could be readily achieved with the addition of F-, which renders the reactivity. The substrates were readily synthesized and proven to be stable at the bench. This bioorthogonal fluoride-responsive click reaction was then successfully employed in peptide modification, protein labeling, and cell imaging, suggesting its potential in various applications.

Gua Lou Er Chen decoction attenuates atherosclerosis by reducing proteoglycans accumulation and inflammation

BACKGROUND

Proteoglycans (PGs) accumulation and inflammation are two interactional pathological processes of atherosclerosis (AS). Up to now, there is no ideal drug for decreasing these pathological changes. Gua Lou Er Chen decoction (GED) has been used to treat AS for several years. However, if GED could treat AS through reducing PGs accumulation and inflammation remains unknown.

PURPOSE

This study was designed to illustrate whether GED could attenuate AS by reducing chondroitin sulphate proteoglycan (CSPG) expressions and alleviating inflammation.

METHODS

In vivo study, apolipoprotein E-deficient mice were fed a high-fat diet to induce AS. In vitro study, oxidised low-density lipoprotein (ox-LDL) and tumour necrosis factor (TNF)-α were used to induce proteoglycans accumulation and inflammation changes of vascular smooth muscle cells (VSMCs) and RAW264.7 macrophages. Oil Red O was used to stain mouse aortic lipid plaque. Haematoxylin eosin staining was used to assess the pathological changes of aortic valve and thoracic aorta. Specialised kits were used to identify blood lipids and sGAGs. Immunofluorescence and immunohistochemistry was used to identify aortic valve CSPG and versican. Western blotting, enzyme-linked immunosorbent assay and quantitative reverse transcription-polymerase chain reaction were used to measure versican, interleukin (IL)-6, TNF-α, and chondroitin sulphate (CS) synthetase expressions. CCK-8 was used to measure the cells proliferation.

RESULTS

In vivo experiments revealed that GED significantly improved hyperlipidemia, lowered lipid plaque deposition in the aorta, and increased plaque stability of AS mice. In addition, further studies revealed that GED lowered the sGAGs, CSPG, and versican levels and down-regulated CS synthetase and inflammatory factor expressions. In vitro experiments revealed that GED decreased TNF-α expression in the RAW264.7 macrophage supernatant stimulated by ox-LDL; decreased versican, CS-related synthetase, and IL-6 expressions; reduced VSMC proliferation stimulated by ox-LDL; down-regulated sGAG and versican expressions of VSMCs stimulated by TNF-α.

CONCLUSION

Our results demonstrated that GED could attenuate AS by reducing hyperlipidemia, hyper-expression of CSPG, and inflammation. This study might provide a novel insight into the development of innovative drug for AS.

A Peptide-Based Ligand-Directed Chemistry Enables Protein Functionalization

The ligand-directed (LD) chemistry provides powerful tools for site-specific modification of proteins. We utilized a peptide with an appended methionine (Met) as a ligand; then, the Met thioether was modified into sulfonium which enabled a proximity induced group transfer onto protein cysteine in the vicinity upon peptide-target binding. The sulfonium warhead could be easily constructed with unprotected peptides, and the transferable group scope was conducted on model protein PDZ and its ligand peptides. In addition, a living cell labeling was successfully achieved.

Investigation of Measurement Accuracy of Bridge Deformation Using UAV-Based Oblique Photography Technique

This paper investigates the measurement accuracy of unmanned aerial vehicle-based oblique photography (UAVOP) in bridge deformation identifications. A simply supported concrete beam model was selected and measured using the UAVOP technique. The influences of several parameters, such as overall flight altitude (h), local shooting distance (d), partial image overlap (λ), and arrangement of control points, on the quality of the reconstructed three-dimensional (3D) beam model, were presented and discussed. Experimental results indicated that the quality of the reconstructed 3D model was significantly improved by the fusion overall-partial flight routes (FR), of which the reconstructed model quality was 46.7% higher than those with the single flight route (SR). Despite the minimal impact of overall flight altitude, the reconstructed model quality prominently varied with the local shooting distance, partial image overlap, and control points arrangement. As the d decreased from 12 m to 8 m, the model quality was improved by 48.2%, and an improvement of 42.5% was also achieved by increasing the λ from 70% to 80%. The reconstructed model quality of UAVOP with the global-plane control points was 78.4% and 38.4%, respectively, higher than those with the linear and regional control points. Furthermore, an optimized scheme of UAVOP with control points in global-plane arrangement and FR (h = 50 m, d = 8 m, and λ = 80%) was recommended. A comparison between the results measured by the UAVOP and the total station showed maximum identification errors of 1.3 mm. The study's outcomes are expected to serve as potential references for future applications of UAVOP in bridge measurements.

Sulfamethoxazole degradation by Pseudomonas silesiensis F6a isolated from bioelectrochemical technology-integrated constructed wetlands

The antibiotic-degrading ability and mechanism of the bacteria in the novel and ecological bioelectrochemical technology-integrated constructed wetlands (BICW) remain unknown. In this study, the sulfamethoxazole (SMX) degrading strain Pseudomonas silesiensis F6a (F6a), which had high degradation efficiency, was firstly isolated from a substrate sample in BICW. The SMX degradation process of F6a follows pseudo first order kinetics. Four metabolic pathways and twelve degradation products were identified. Based on genomics and proteomics analysis, six key SMX-degrading genes, Gene4641 deoC, Gene0552 narI, Gene0546 luxS, Gene1753 nuoH, Gene0655 and Gene4650, were identified, which were mainly participated in C-S cleavage, S-N hydrolysis and isoxazole ring cleavage. Interestingly, we found the corresponding sulfonamides resistance genes were not detected in F6a, which may provide an evidence for low abundance of the sulfonamides resistance genes in BICW system. These findings would contribute to a better understanding of biotransformation of antibiotic in the BICW.

[Clinical analysis of 24 cases of synovial sarcoma of head and neck]

Objective: To investigate the pathological characteristics, treatment and prognosis of synovial sarcoma of head and neck. Methods: The clinical data of 24 patients with synovial sarcoma of the head and neck treated in the First Affiliated Hospital of Zhengzhou University from January 2012 to December 2020 were retrospectively analyzed. There were 16 males and eight females, aged 17 to 75 years. The pathological features, treatment and follow-up were summarized. Cumulative survival was estimated by Kaplan-Meier method. Results: All patients' diagnoses were confirmed by pathological examinations. Most cases showed the tumors were composed of spindle cells under microscope, with the characteristics of malignant tumor cells, and some tumors also showed epithelioid cell morphology, forming the typical pathological characteristics of biphasic differentiation. Except for one patient who could not tolerate surgery and the diagnosis was only confirmed by biopsy, the remaining 23 patients received surgical treatment, including three patients receiving surgical treatment alone, five patients receiving post-operative adjuvant radiotherapy, seven patients receiving post-operative adjuvant chemotherapy, and eight patients receiving post-operative adjuvant radiotherapy. Follow-up time was 3.0-114.1 months (median follow-up time: 25.2 months), including two cases of loss to follow-up, 10 cases of recurrence, five cases of lung metastases, one case of bone metastasis, and 12 cases of death. The 1-year, 3-year and 5-year survival rates for the 24 patients with synovial sarcoma of head and neck were 74.4%, 58.9% and 39.2%, respectively. Conclusion: Synovial sarcoma of the head and neck has a high recurrence rate, common distant metastasis and poor prognosis. Histopathology and immunohistochemical examinations are an important basis for diagnosis, if necessary, combined with molecular genetics. Surgical resection is the main treatment, preferring radical or expanded resection.

Effect of garlic essential oil in 97 patients hospitalized with covid-19: A multi-center experience

To observe the synergistic effect of garlic essential oil in patients with novel coronavirus disease (COVID-19), in addition to the routine treatment, we used garlic essential oil in COVID-19 patients with mild to moderate symptoms and compared their results to those of patients who did not receive the essential oil. We conducted a quasi-experimental study with COVID-19 patients from 3 hospitals. In the experimental group, 97 patients received garlic essential oil combined with conventional treatment. In the control group, 100 patients received only the conventional treatment for COVID-19. The effectiveness and safety of the garlic essential oil were assessed. Compared to the control group, the group receiving garlic essential oil showed a shorter duration of symptoms, shorter time to negative nucleic acid testing (NAT) results and shorter time to improvement on the computed tomography (CT). In the same period, the experimental group showed an increase in the rate of the disappearance of symptoms and the improvement rates of NAT and CT. Due to its effectiveness and safety in patients with COVID-19, garlic essential oil is recommended as a preventive measure or a supportive therapy during the COVID-19 pandemic.

Flavin catalyzed desulfurization of peptides and proteins in aqueous media

A biomimetic method has been established for the chemo-selective desulfurization of cysteinyl peptides and proteins in aqueous media. The derivatives of biocatalytic cofactors, flavins, were found to be efficient photosensitizers in a thiyl-radical-mediated desulfurization of Cys. The reaction was conducted in an ultrafast manner with both polypeptides and proteins.

Perfluorohexanoic acid caused disruption of the hypothalamus-pituitary-thyroid axis in zebrafish larvae

Perfluorohexanoic acid (PFHxA) has been recognized as an alternative to the wide usage of perfluorooctanoate (PFOA) and perfluorooctane sulfonate (PFOS) in the fluoropolymer industry for years. PFHxA has been frequently detected in the environment due to its wide application. However, the ecological safety of PFHxA, especially its toxicological effects on aquatic organisms, remains obscure. In the present study, PFHxA at different concentrations (0, 0.48, 2.4, and 12 mg/L) was added to the culture medium for zebrafish embryo/larval exposure at 96 h postfertilization (hpf). Zebrafish larvae showed a slow body growth trend and changes in thyroid hormone levels (THs) upon PFHxA exposure, indicating the interference effect of PFHxA on fish larval development. Moreover, the transcription levels of genes related to the hypothalamic-pituitary-thyroid (HPT) axis were also analyzed. The gene expression level of thyroid hormone receptor β (trβ) was upregulated in a dose-dependent manner. Exposure to 0.48 mg/L PFHxA increased the expression levels of the thyrotrophic-releasing hormone (trh) and thyroid hormone receptor α (trα). Significant increases in corticotrophin-releasing hormone (crh) and transthyretin (ttr) gene expression were also observed when the zebrafish larvae were treated with 12 mg/L PFHxA, except iodothyronine deiodinases (dio1), which decreased obviously at that point. There were significant declines in the transcription of both thyroid-stimulating hormone β (tshβ) and uridinediphosphate-glucuronosyltransferase (ugt1ab) upon exposure to 2.4 mg/L PFHxA. In addition, PFHxA induced a dose-related inhibitory effect on the transcription of sodium/iodide symporter (nis). Finally, the thyroid status will be destroyed after exposure to PFHxA, thus leading to growth impairment in zebrafish larvae.

Nitrogen removal from summer to winter in a field pilot-scale multistage constructed wetland-pond system

A pilot-scale multistage constructed wetland-pond (MCWP) system with a "pre-ecological oxidation pond, two-stage horizontal subsurface flow constructed wetland (HSCW) and surface flow constructed wetland (SFCW) as the core and postsubmerged plant pond" as the process was used to treat actual polluted river water in the field, and the variation in nitrogen removal from summer to winter was investigated. The results showed that the average total nitrogen (TN) removal efficiency in the MCWP was approximately 40.74%. The significant positive correlation between the daily highest temperature and the TN removal efficiency of the whole system was fitted with a nonlinear curve (R² = 0.7192). The TN removal load rate in the HSCWs was 2.7-3.7 times that in the SFCW. The SFCW, which had high-density plants (35 plants/m²), increased the proportion of nitrogen removed by plant harvesting and microbial function. The TN transformed by Iris pseudacorus L. accounted for 54.53% in the SFCW. Furthermore, bacteria completed the nitrogen cycle in the SFCW through a variety of nitrogen removal pathways. This research not only investigated the TN removal performance in an MCWP system but also made it possible to predict the TN removal efficiency according to the daily highest temperature from summer to winter in the field.

Histidine-specific bioconjugation via visible-light-promoted thioacetal activation

Histidine (His, H) undergoes various post-translational modifications (PTMs) and plays multiple roles in protein interactions and enzyme catalyzed reactions. However, compared with other amino acids such as Lys or Cys, His modification is much less explored. Herein we describe a novel visible-light-driven thioacetal activation reaction which enables facile modification on histidine residues. An efficient addition to histidine imidazole N3 under biocompatible conditions was achieved with an electrophilic thionium intermediate. This method allows chemo-selective modification on peptides and proteins with good conversions and efficient histidine-proteome profiling with cell lysates. 78 histidine containing proteins were for the first time found with significant enrichment, most functioning in metal accumulation in brain related diseases. This facile His modification method greatly expands the chemo-selective toolbox for histidine-targeted protein conjugation and helps to reveal histidine's role in protein functions.

Functionalization of histidine residues in proteins via visible-light-promoted thioacetal activation is reported. ∼2000 proteins with reactive and exposed histidine residues from the MCF7 cell line are characterized using ABPP by this method.

Evaluation of the acute toxicity and neurodevelopmental inhibition of perfluorohexanoic acid (PFHxA) in zebrafish embryos

Perfluorohexanoic acid (PFHxA), a widely used emerging alternative for 8-carbon PFAAs, has been detected at a high level in the water environment. While its toxicity and environmental health risk are still largely unknown in aquatic life. The present study aimed to evaluated the possible developmental neurotoxicity induced by PFHxA exposure (0, 0.48, 2.4, and 12 mg/L for 120 h) in the zebrafish embryo. Here, both developmental endpoints, neurotransmitters concentrations, locomotor behavior were analyzed. No significant effects on mortality, malformation rate, and growth delay were detected in the low dose treatment groups except for in the high dose group (12 mg/L). A significant increase in swimming speed were noted in the 0.48 mg/L group. Other changes including neurotransmitters concentrations and green fluorescent protein (GFP) expression in Tg (HuC-GFP) zebrafish larvae were significantly increased in 12 mg/L group. Beyond that, genes related to neurodevelopment were significantly decreased in larvae. Moreover, downregulations of protein expression levels of α1-tubulin, elavl3, and gap43 were identified. These results demonstrate that the PFAAs alternative PFHxA have no significant neurodevelopmental effects on zebrafish larvae under acute low-dose exposure, while, it is important to note that PFHxA perform inhibiting effects on neurotransmitter and central nervous system under a relatively high dose. This in vivo study could provide reliable toxicity information for risk assessments of PFHxA on aquatic ecosystems. CAPSULE: PFHxA have no significant neurodevelopmental effects on zebrafish larvae under acute low-dose exposure, while exposed with relatively high-dose, could induced the alternations of neurotransmitter concentrations as well as the genes involved in the early developmental stages of zebrafish, leading to the impairment of the nervous system in zebrafish larvae.

Performance and mechanism of sulfamethoxazole removal in different bioelectrochemical technology-integrated constructed wetlands

Sulfamethoxazole (SMX) has a high concentration and detection frequency in aquatic environments due to the poor removal efficiency of traditional biological treatment processes. Bioelectrochemical technology-integrated constructed wetlands (CWs) have great potential for SMX removal; however, the process of SMX removal in different bioelectrochemical technology-integrated CWs (microbial fuel cell (MFC) and direct current (EC)) remains unclear. To address this, we examined the mechanism of SMX removal in MFCCW and ECCW. The results revealed that the SMX removal efficiency can reach 96.0 ± 2.4% in the ECCW and 97.2 ± 2.2% in the MFCCW. The enhancement of MFC for SMX removal in CW was slightly better than that in direct current (p > 0.05). It was found that the adsorption process of SMX in the substrate promoted by EC was more enhanced than that by MFC. Furthermore, bioelectrochemical technology improved plant activity, including root and enzymatic (superoxide dismutase, peroxidase, and catalase) activities, and fluorescence parameters (photochemical quenching coefficient, non-photochemical quenching coefficient, and quantum efficiency of PS II). Significant differences were found between CW and ECCW (p < 0.05), while no significant differences were found between CW and MFCCW (p > 0.05). The microbial activity and abundance in CW were improved by bioelectrochemical technology, and the microbial community structure was optimised to be simpler and more stable. However, EC tended to promote microbial and plant activity in CW, whereas MFC tended to optimise the microbial community and improve the tightness and stability of the module. The enhanced difference might also account for the changes in the SMX degradation pathway. 4-aminobenzenesulfonic acid (TP174), 3-amino-5-methylisoxazole (TP99) and 5-methylisoxazole (TP84) were all common products in the three reactors, whereas TP99 underwent further ring-opening in MFCCW and TP174 underwent further hydrolysis in ECCW. This study provided an important reference for the targeted regulation of plants and microorganisms in constructed wetlands via different bioelectrochemistry to enhance characteristic pollutants degradation.

Capture the contagion network of bitcoin - Evidence from pre and mid COVID-19

COVID-19 is the first global scale crisis since the inception of Bitcoin. We compare the contagion phenomenon of Bitcoin and other financial markets or assets pre and during the COVID-19 shock in both contemporaneous and non-contemporaneous manner. This paper uses the directed acyclic graph (DAG), spillover index, and network topology to provide strong evidence on the directional contagion outcomes of Bitcoin and other assets. The empirical results show that the contagion effect between Bitcoin and developed markets is strengthened during the COVID-19 crisis. Particularly, European market has a dominant role. Excluding Bitcoin's own shocks, United State and European markets are the main contagion sources to Bitcoin. European market also works as a intermediary to deliver infectious from United State and market fear. The findings show that gold always has contagion effect with Bitcoin, while gold, US dollar and bond market are the contagion receivers of Bitcoin under the shock of COVID-19. The empirical results further proved the safe haven, hedge and diversifier potential of Bitcoin in economic stable time, but also shows that the sustainability of these properties is undermined during the market turmoil.

The application of steel slag in a multistage pond constructed wetland to purify low-phosphorus polluted river water

To investigate the effect of a constructed wetland (CW) with steel slag as the filler on water contaminated by low phosphorus levels, a multistage pond CW system was designed in this study. Low-phosphorus polluted river water was used as the research object. This study explored the effects of using steel slag as a CW filler on phosphorus removal and the total phosphorus (TP) purification effect of the wetland system. The results showed that the TP removal rates in the ecological pond, oxidation pond, surface flow wetlands and submerged plant pond were 5.17%, 8.02%, 21.56%, and 16.31%, respectively. Intermittent increases in phosphorus concentration were observed in the reactors and were caused by the decay of plant tissues, which released pollutants. Because steel slag was added to the filler, the TP concentrations in the effluent of the first- and second-level horizontal subsurface CWs increased by 151.13% and 16.29%, respectively, compared to the influent concentration. The 20th to 40th days of the test run was a period of rapid phosphorus release of the system. The use of steel slag has a potential risk of phosphorus release when applied in CWs used to purify low-phosphorus contaminated water bodies.

Performance and bacterial community dynamics of hydroponically grown Iris pseudacorus L. during the treatment of antibiotic-enriched wastewater at low/normal temperature

Antibiotics are widely detected in the water environment, posing a serious threat to the health of humans and animals. The effect of levofloxacin (LOFL) on pollutant removal and the difference in the influence mechanisms at normal and low temperatures in constructed wetlands are worth discussing. A hydroponic culture experiment was designed with Iris pseudacorus L. at low and normal temperatures. LOFL (0-100 µg/L) was added to the systems. The results indicated that the removal of pollutants was affected most by temperature, followed by LOFL concentration. At the same concentration of LOFL, the pollutant removal rate was significantly higher at normal temperature than at low temperature. Low concentrations of LOFL promoted the degradation of pollutants except TN under normal-temperature conditions. Compared with the results at low temperature, the bacterial community richness was higher and the diversity of bacterial communities was lower under normal-temperature conditions. The genera and the function of bacteria were greatly affected by antibiotic concentration, temperature and test time. A series of microorganisms resistant to antibiotics and low temperature were identified in this study. The results will provide valuable information and a reference for our understanding of the ecological effects of LOFL.

Response of Cyperus involucratus to sulfamethoxazole and ofloxacin-contaminated environments: Growth physiology, transportation, and microbial community

Plant-microbe is a complementary coupling system for antibiotics removing in constructed wetlands (CWs), but how plant and rhizosphere microbiomes respond to antibiotics exposure and the occurrence of ARGs in this microenvironment have seldom been researched. Thus, the response of the plant-microbe coupling system to different levels of antibiotics (sulfamethoxazole (SMZ) and ofloxacin (OFL)) was investigated. The results showed that two antibiotic stressors have hormetic effects on plant growth, physiology, and microbial community evolution, and the antibiotic toxic effects presented as SMZ + OFL > SMZ > OFL. Antibiotic accumulation in the plants was in the order of roots > stems > leaves. Notably, the root attachments affected antibiotic transportation. The accumulation of antibiotics in the under-ground parts affected the rhizosphere microbial community structure, and the microorganisms were more sensitive to SMZ + OFL than the plants, with inflection points of 0.5 mg L^-1 and 1 mg L^-1, respectively. Pseudomonas was highly resistant to antibiotics, while Acidovorax and Devosia may play a role in antibiotic degradation. Correlation analysis and network analysis showed that antibiotic enrichment and the bacterial community contributed significantly to the abundance of antibiotic-resistant genes (ARGs), further revealing the co-occurrence of int1, ARGs, and the potential bacterial hosts.

Accumulation characteristics and biological response of ginger to sulfamethoxazole and ofloxacin

The potential risk to human health of antibiotics that pass through the food chain has become an important global issue, but there are few reports on the response of ginger (Zingiber officinale) to antibiotic pollution. In this study, we investigated the enrichment characteristics and biological response of ginger to sulfamethoxazole (SMZ) and ofloxacin (OFL) residues, which are common in the environment. Lower levels of SMZ, OFL and their combined duplex treatment (SMZ+OFL) promoted the growth of ginger, but the critical doses necessary to stimulate growth differed among treatments: 10 mg L-1 SMZ, 1 mg L-1 OFL and 1 mg L-1 (SMZ+OFL) had the strongest stimulating effects. At higher dosages, the root growth and light energy utilization efficiency of ginger were impaired, and (SMZ+OFL) had the strongest inhibitory effect. Treatments with lower levels of antibiotics had no significant effect on reactive oxygen species and antioxidant enzyme activities. However, when SMZ, OFL and SMZ+OFL concentrations exceeded 10 mg L-1, the contents of H2O2, O2- and MDA continued to increase, while the activities of SOD, POD, CAT first increased and then decreased, especially in SMZ+OFL. Ginger accumulated more SMZ and OFL in rhizomes and less in leaves, and accumulation increased significantly as antibiotic concentration increased. When SMZ concentration was 1 mg L-1, the SMZ concentrations in rhizomes, roots, and leaves were 0.23, 0.15, and 0.05 mg kg-1, respectively, and the residual SMZ in the rhizome was 2.3 times higher than the maximum residue limit. The abundance of the resistance genes sul1, sul2, qnrS, and intI1 increased with increasing antibiotic concentrations, and intI1 abundance was the highest. OFL induced higher levels of intI1 expression than did SMZ.

[Evaluation of inferior mesenteric vessel and ureter by contrast-enhanced abdominal pelvic CT and its clinical influence on laparoscopic rectal surgery]

Objective: To assess the anatomic relationship of inferior mesenteric artery (IMA)/inferior mesenteric vein (IMV) with ureter by contrast-enhanced abdominal pelvic CT, in order to provide guidance for vascular management and ureteral protection in laparoscopic rectal surgery. Methods: A retrospective cohort study was conducted. Image data of contrast-enhanced abdominal pelvic CT at Department of Medical Radiography of Peking University First Hospital in November 2018 were enrolled. Exclusion criteria: (1) previous history of abdominal or pelvic surgery; (2) scoliosis deformities; (3) missing images; (4) minors; (5) inferior mesenteric vascular disease or tumor involvement resulting in suboptimal imaging; (6) poor image quality. Finally, contrast-enhanced abdominal pelvic CT data of 249 cases were collected, including 120 males and 129 females with mean age of (60.1±13.4) years. Multi-planar reconstruction (MPR) and maximum intensity projection (MIP) were used to evaluate the anatomic relationship of IMA/IMV with ureter. IMA root location, IMA length, branch types of IMA, distance between major branches, distance between IMA/IMV and ureter at the level of root of IMA, left colic artery (LCA) root, abdominal aortic bifurcation, and sacral promontory were measured and association between IMA/IMV and ureter site was summarized. Results: The distance from IMA root to the aortic bifurcation and sacral promontory was (42.0±8.5) mm and (101.8±14.0) mm, respectively. The length of IMA was (38.5±10.7) mm. The proportion of IMA roots locating at levels of the 2nd, 3rd, and 4th lumbar vertebra was 3.2% (8/249), 79.5% (198/249), and 17.3% (43/249), respectively. The higher the level of the lumbar vertebra, the longer the IMA [length of IMA originating from the 2nd, 3rd, 4th lumbar vertebra level: (42.4±10.9) mm, (39.5±10.4) mm, (33.0±10.9) mm, respectively; F=7.48, P<0.001]. In 111 cases (44.6%), LCA arose independently from IMA (type 1), and the distance between LCA and the first branch of sigmoid artery (SA) was (15.0±7.4) mm; in 56 cases (22.5%), LCA and SA had a common trunk (type 2), with a length of (11.0±8.5) mm; in 78 cases (31.3%), LCA branched with SA at the same point (type 3); LCA was absent in 4 cases (1.6%)(type 4). The length of IMA in LCA-deficient type 4 was (54.8±18.0) mm, which was longer than (38.2±10.5) mm in LCA-presence type (type 1, type 2 and type 3) and the difference was statistically significant (t=-3.11, P=0.002). The distance between the ureter and IMA was the longest at the level of IMA root [(35.7±8.1) mm], was the shortest at the level of the aortic bifurcation [(22.4±6.4) mm], and the distance between the ureter and IMA in different planes was significantly different (F=185.70, P<0.001). The distance between the ureter and IMV was the longest at the level of the sacral promontory [(21.1±9.0) mm], was the shortest at the level of LCA root [(12.0±5.7) mm], whose difference was also statistically significant (F=87.66, P<0.001). Conclusions: CT post-processing techniques including MPR and MIP can efficiently and accurately assess the branch types of IMA and anatomical relationship between IMA/IMV and ureter, and provide insights into laparoscopic rectal surgery for surgeons. IMA/IMV and ureter depart farthest at the level of IMA root. Artery first and plane second strategy in the middle approach of laparoscopic rectal surgery is considerable and feasible.

[Preoperative evaluation using multi-slice spiral CT angiography of right-side colon vascular in laparoscopic radical operation for right colon cancer]

Objectives: To examine the value of multi-slice spiral CT angiography (MSCTA) in the analysis of anatomical variation and structural classification of right colon vessels. Methods: From August 2015 to August 2017, 198 patients (96 of whom underwent laparoscopic radical resection of right colon cancer) at Department of General surgery of Peking University First Hospital were retrospectively collected, and the results of abdominal enhanced CT scan were collected and three-dimensional reconstruction of blood vessels was performed. There were 104 males and 94 females. The age was 64(27) years (M(Q(R)), range: 19 to 87 years). Right gastroepiploic vein, anterior superior pancreaticoduodenal vein, right colonic vein (RCV), superior right colonic vein, ileocolon artery or vein (ICA or ICV), middle colon artery or vein (MCA or MCV) and Henle trunk were observed and recorded respectively. The anatomical relationship between the positions of blood vessels, the length of Henle trunk and surgical trunk were measured. Results: ICV and ICA were the most constant anatomic structures. The ICV/ICA of all patients came directly from SMV/SMA, 36.9% (73/198) ICV going in front of SMV and 63.1% (125/198) behind SMV. 72.2% (143/198) of the patients had RCV imported into Henle trunk and the rest into SMV. Middle colonic vein (MCV) could be observed in 81.3% (161/198) of the cases. 81.4% (131/161) of MCV were imported into SMV, 16.8% (27/161) into Henle trunk, 1.2% (2/161) into the first jejunal vein and 0.6% (1/161) into the splenic vein. Henle trunk was divided into 4 types, among which the occurrence probability of gastric node and pancreatic trunk was the highest. The dry length of Henle trunk was (0.82±0.39) cm (range: 0.37 to 1.68 cm). The length of surgical trunk was (2.54±0.83) cm (range: 1.57 to 3.95 cm). Accuracy of MSCTA results was 96.9%(93/96). Conclusions: Anatomical variation of blood vessels in the right colon is common. Abdominal CT angiography can accurately determine the anatomical structure of the blood vessels in the right colon.

A review on removing antibiotics and antibiotic resistance genes from wastewater by constructed wetlands: Performance and microbial response

Pollution caused by antibiotics has been highlighted in recent decades as a worldwide environmental and health concern. Compared to traditional physical, chemical and biological treatments, constructed wetlands (CWs) have been suggested to be a cost-efficient and ecological technology for the remediation of various kinds of contaminated waters. In this review, 39 antibiotics removal-related studies conducted on 106 treatment systems from China, Spain, Canada, Portugal, etc. were summarized. Overall, the removal efficiency of CWs for antibiotics showed good performance (average value = over 50%), especially vertical flow constructed wetlands (VFCWs) (average value = 80.44%). The removal efficiencies of sulfonamide and macrolide antibiotics were lower than those of tetracycline and quinolone antibiotics. In addition, the relationship between the removal efficiency of antibiotics and chemical oxygen demand (COD), total suspended solids (TSS), total nitrogen (TN), total phosphorus (TP) and ammonia nitrogen (NH₃-N) concentrations showed an inverted U-shaped curve with turning points of 300 mg L^-1, 57.4 mg L^-1, 40 mg L^-1, 3.2 mg L^-1 and 48 mg L^-1, respectively. The coexistence of antibiotics with nitrogen and phosphorus slightly reduced the removal efficiency of nitrogen and phosphorus in CWs. The removal effect of horizontal subsurface flow constructed wetlands for antibiotic resistance genes (ARGs) had better performance (over 50%) than that of vertical wetlands, especially for sulfonamide resistance genes. Microorganisms are highly sensitive to antibiotics. In fact, microorganisms are one of the main responsible for antibiotic removal. Moreover, due to the selective pressure induced by antibiotics and drug-resistant gene transfer from resistant bacteria to other sensitive strains through their own genetic transfer elements, decreased microbial diversity and increased resistance in sewage have been consistently reported. This review promotes further research on the removal mechanism of antibiotics and ARGs in CWs.

Occurrence and ecological risk of pharmaceutical and personal care products in surface water of the Dongting Lake, China-during rainstorm period

The pharmaceutical and personal care product (PPCP) residues in freshwater lakes are being highlighted around the world. The occurrence and ecological risk of 34 PPCPs classified as antibiotics, non-steroidal anti-inflammatory drugs (NSAID), cardiovascular drugs, psychotropic drugs, anti-inflammatory drugs, psychostimulants, and pesticides during rainstorm period in surface water of the Dongting Lake, China, were studied. Twenty-six out of thirty-four PPCPs were detected, and the total concentrations of antibiotics ranged from 0.15 to 214.75 ng L^-1 in surface water. The highest average concentration was observed for diclofenac, followed by diethyltoluamide (DEET). The PPCP concentrations were much lower in Dongting Lake compared to other rivers and lakes due to the strong dilution effect of rainstorm, while the detection rate remains high. Caffeine and DEET were detected with 100% frequency in Dongting Lake, and the detection rates of diclofenac, mefenamic acid, and roxithromycin were above 90%. The pollution levels of antibiotics decreased in the order of East Dongting Lake > South Dongting Lake > West Dongting Lake, which may be related to the distribution of aquaculture plants, sewage treatment plants, and population density. The risk quotient (RQ) method was used to evaluate ecological environment risk under the worst case and the results suggested that clarithromycin, diclofenac, roxithromycin, and erythromycin might pose a significant risk to aquatic organisms in Dongting Lake, especially clarithromycin. This study can provide data support for further research on the dilutive effect and mechanism of rainwater runoff on PPCPs in lakes on a large scale.

Morphological traits of submerged macrophytes reveal specific positive feedbacks to water clarity in freshwater ecosystems

Positive feedbacks are generally related to the interactions between biotic processes and abiotic drivers and may lead to the emergence of alternative stable states in ecosystems. Understanding the mechanisms of self-reinforcing feedbacks in a macrophyte-dominant clear state is critical for lake management. Based on a survey of 35 lakes in the Yangtze River floodplain and canonical correspondence analysis (CCA) with forward selection, the results showed that water clarity is the most limiting factor that influences the community structure and biomass of submerged macrophytes. The canopy length of tall macrophytes (i.e., Myriophyllum spicatum L. and Potamogeton malaianus Miq.) showed positive allometry with plant height, while the canopy length of small macrophytes (e.g., Potamogeton maackianus A. Benn.) showed isometry. Our results indicated the existence of positive feedbacks between macrophyte vegetation and water clarity in a "more vegetation, higher water clarity" pattern. We found that the relationships between monospecific community biomass and water clarity differed among community types, indicating that the strength of the positive feedback was interspecific. Furthermore, we found significant differences in the Secchi depth (SD), chlorophyll a (Chl a), light attenuation coefficient (K) and dissolved oxygen (DO) associated with monospecific macrophyte patches. Plant height had significant relationships with the mean values of SD, Chl a, total phosphorus (TP) and K, suggesting that plant height was one of the mechanisms underlying the positive feedbacks. In management practices, efforts to build and maintain the resilience of an ecosystem should be trait-based rather than merely focusing on vegetation abundance.

Occurrence and fate of antibiotics and antibiotic resistance genes in typical urban water of Beijing, China

The pollution of antibiotics and antibiotic resistance genes (ARGs) has been highlighted on a global scale because of their serious threats to the environment and human health. Typical urban water in cities with high population density are ideal mediums for the acquisition and spread of antibiotics and ARGs. The pollution level of a broad range of antibiotics and ARGs in hospital wastewater, groundwater and the Wenyu River, and their fates through three sewage treatment plants (STPs) were investigated in this study. The concentrations of the 11 detected antibiotics ranged from not detected (ND)-16800 ng L^-1 in diverse water samples from Beijing, and fluoroquinolones were detected at the highest concentration, especially in the hospital samples. The maximum concentrations of antibiotics in STPs and hospital were 1-3 orders of magnitude higher than those in the surface water from Wenyu River and groundwater. Good removal efficiencies by treatment processes were observed for tetracyclines and quinolones, and low removal efficiencies were observed for sulfonamides and macrolides. These results also revealed that the sulfonamide resistance genes (sul1, sul2) and macrolide resistance genes (ermB) were detected at the highest relative abundances (7.11 × 10^-2-1.18 × 10^-1) in the water bodies of Beijing. It was worth noting that sul1 abundance was the highest in groundwater samples. The relative abundance of most ARGs in STPs exhibited a declining trend in the order of influent > secondary effluents > effluent. However, the relative abundance of sul 1, sul 2 and tetC in the effluent was higher than those in the influent. The incomplete removal of antibiotics and ARGs in STPs poses a serious threat to the receiving rivers, and affects ecosystem security. Overall, our findings provide favorable support for a further investigation of the spread and risk of antibiotics and ARGs from diverse sources (e.g., STPs and hospitals) to the aquatic environment.

Removal of nitrogen from low pollution water by long-term operation of an integrated vertical-flow constructed wetland: Performance and mechanism

The efficiency of nitrogen removal and its mechanism, aquatic organism distribution characteristics and regeneration capability of zeolite from an integrated vertical-flow constructed wetland (IVFCW) for low pollution water treatment were evaluated after steady and continuous operation for eight years. After running for eight years, better than average COD and NH₄⁺-N removal were observed in the IVFCW. The NH₄⁺-N removal rate in this system was controlled by ammoxidation and adsorption and ion exchange of zeolite. The low total nitrogen (TN) removal efficiency was due to NO₃^--N accumulation and zeolite desorption. In addition, this phenomenon indicated that because of poor organic carbon sources, nitrification was stronger than denitrification, consistent with the distribution of the functional genes for nitrification and denitrification. The biological activity in this system was abundant, especially that of spirogyra and navicula. The saturated adsorption capacity of zeolite was as high as 1.35 mg g^-1 with a desorption rate of <20%. There were no obvious differences among the effects of aeration, water cleaning, drained reoxygenation and steam stripping for zeolite regeneration (adsorption capacity of >50%). However, the drained reoxygenation performance of was better due to zero energy consumption and regeneration in situ.

A review on occurrence and risk of polycyclic aromatic hydrocarbons (PAHs) in lakes of China

Polycyclic aromatic hydrocarbons (PAHs) residues have attracted attention worldwide. This study summarizes the current levels of PAH exposure in the water environments of lakes. In addition, the risk levels from individual PAHs and ΣPAHs in the water environments of lakes in China were evaluated by incremental lifetime cancer risk (ILCR) assessment, the toxic equivalent concentration (TEQ_BaP), the risk quotient (RQ), the effects range-low (ERL) and the effects range-median (ERM). The results showed that the concentrations of ∑PAHs in water and sediment ranged from 4.0 to 12,970.8 ng L^-1 and 6.52 to 7935.21 ng g^-1, respectively, and the highest concentrations of individual PAHs were of naphthalene (Nap) (6525 ng L^-1), followed by indeno(1,2,3‑cd)pyrene (IcdP) (3452.6 ng g^-1). Concentrations in the Great Lakes region in China showed spatial difference, with the Qinghai-Tibet Plateau Lakes District and Mongolia-Xinjiang Lakes District being less polluted. However, the pollution level of PAHs in lakes is relatively high at the global scale. The ecological risk assessment found a moderate level of ∑PAHs in water, but benz(a)anthracene (BaA) and phenanthrene (Phe) had high RQ values, which might pose a significant risk to aquatic organisms in lakes. Although the contents of ∑PAHs in sediments are low, most individual PAHs pose potential risks, especially acenaphthene (Ace), fluorene (Flu) and dibenz(a,h)anthracene (DahA). This study revealed the pollution levels of PAHs across China and provided a scientific basis for PAH pollution control and environmental protection.

A review on removal of organophosphorus pesticides in constructed wetland: Performance, mechanism and influencing factors

The residues of organophosphorus pesticides (OPPs) have been widely detected in rivers, the gulf, and even groundwater and drinking water, which may pose a serious threat to aquatic ecosystems and human health. Compared to other treatments, constructed wetlands (CWs) have been demonstrated to be a cost-effective alternative risk mitigation strategy for non-point-source pesticide pollution. This review summarizes 32 studies related to the remediation of OPPs in 117 CWs during 2001-2017 worldwide. The performances, mechanisms and influencing factors in the studies are comprehensively and critically reviewed in this paper. Overall, the OPPs were efficiently removed with an efficiency up to 87.22 ± 16.61%. The removal efficiency, differences and related reasons among different types of CWs in developed and developing countries and the different types of OPPs in CWs are well-evaluated in detail. In addition, the main processes for OPPs removal in CWs involve phytoremediation (plant uptake, phytoaccumulation, phytovolatilization and phytodegradation), substrate adsorption or sedimentation, and biodegradation. Based on the quantitative analysis by mass balance, for water-soluble pesticides, the dominant removal process was via microbiological degradation. This result was in contrast to findings obtained with hydrophobic OPPs, for which the dominant processes were biodegradation and sorption by substrate. Therefore, the behavior of microbial transformation prevails. Additionally, the presence of plants can facilitate the elimination of OPPs in CWs, promoting the process by an average percentage of approximately 6.19 ± 9.46%. Statistical analysis shows that loading of inlet OPPs is the largest limiting factor and that the HRT and T are the most significant parameters that influence the efficiency of trapping OPPs in CWs. Simultaneously, we can also obtain suitable parameters for the design and operation of CWs. This review promotes further research on plant-microbe joint combined remediation and examines the different behaviors of water-soluble and hydrophobic OPPs in CWs.

Occurrence and health risk assessment of volatile organic compounds in the surface water of Poyang Lake in March 2017

An investigation into the occurrence of volatile organic compounds (VOCs) in the surface water of Poyang Lake was conducted. The determination of 54 different kinds of VOCs was performed with a purge and trap-gas chromatography-mass spectrometry method at 28 sampling points. Twenty-two types of VOCs were detected; methylene chloride had the highest mean concentration of 708.19 ng L⁻¹, followed by 1,2-dichloroethane and chloroform, with mean concentrations of 376.78 and 187.26 ng L⁻¹, respectively. The distribution of VOCs in the areas of Poyang Lake from low to high was as follows: west and south < east and central; the highest ∑VOC concentration occurred at the sample site of Zhangsihe. The health risks of VOCs in Poyang Lake were also determined by calculating the cancer and non-cancer risk from the two exposure routes of ingestion and dermal adsorption. The results showed that VOCs have no carcinogenicity risk, while only methylene chloride has a certain carcinogenic risk to the human body.

An investigation into the occurrence of volatile organic compounds (VOCs) in the surface water of Poyang Lake was conducted.

Occurrence and risk assessment of heavy metals in water, sediment, and fish from Dongting Lake, China

In this study, 15 representative surface waters and sediments and seven typical fish were collected during the wet season in 2016 to explore the occurrence, chemical fractionation, and ecological risk of heavy metals (Cu, Zn, Pb, Cd, Cr, Hg, As, and Ni) in aquatic ecosystems of Dongting Lake in China. In surface water, the concentrations of all elements were lower than the third grade of the surface water quality standards (GB3838-2002). The highest concentrations of Zn, Pb, Cd, Ni, and Cu were found in the outlet of Dongting Lake, whereas As and Cr were highest in the Xiangjiang River Delta area. In surface sediments, the concentration decreased in the order of Zn > Cr > Pb > Cu > Ni > As>Cd > Hg; the highest concentration of all elements, except for Hg, was located in the Xiangjiang River Delta area; for chemical fractionation, Cr, Hg, Zn, As, Ni, and Cu were mainly residual fractionation; and Pb and Cd were mainly in a reducible state and fraction soluble in acid, respectively. In fish muscle, the concentrations of all elements were lower than relevant standards; the highest concentration appeared in fish living in the middle-lower and demersal layers. As for the feeding habits of fish, the average concentration decreased in the order of carnivorous > omnivorous > herbivorous fish. The potential ecological risk and the ratio of secondary phase to primary phase assessment showed that Cd and Hg had the highest ecological risk and that Cd and Pb had a high risk of secondary release. A health risk assessment showed that drinking water and fish for consumption in urban and rural areas around Dongting Lake were in the acceptable level.

Occurrence of typical antibiotics and source analysis based on PCA-MLR model in the East Dongting Lake, China

The antibiotics residues in freshwater lakes are being highlighted around the world because of high potential threat to environment and human health. Understanding the current state of antibiotics and potential sources in lakes are important. The potential sources of antibiotics (Sewage treatment plants (STPs)), livestock and poultry farms and fishponds in the East Dongting was studied. Compared with other surface water bodies, the concentration of antibiotic in the East Dongting Lake was at a moderate or low level. Ten of 12 antibiotics likely originated from veterinary applications in livestock and poultry farms, especially in swine farms, and concentrations at these sources (ND-1240.41 ng L^-1) were 1-3 orders of magnitude higher than in the effluent of local sewage treatment plants and fishponds. Based on a principal component analysis with multiple linear regression (PCA-MLR) model, we estimated source contributions of 79.95% for livestock and poultry farms, 0.27% for STPs, and 19.79% for aquaculture source and livestock and poultry farms. Overall, the predominance of sulfonamides and livestock and poultry farms in the East Dongting Lake has been identified, which can provide important information for regulating their veterinary use and environmental management.

Perfluorododecanoic acid exposure induced developmental neurotoxicity in zebrafish embryos

Perfluorododecanoic acid (PFDoA), an artificial perfluorochemical, has been widely distributed in different ambient media and has been reported to have the potential to cause developmental neurotoxicity. However, the specific mechanism is largely unknown. In the current study, zebrafish embryos were treated with 0, 0.24, 1.2, and 6 mg/L PFDoA for 120 h. Exposure to PFDoA causes serious decreases in hatching delay, body length, as well as decreased locomotor speed in zebrafish larvae. Additionally, the acetylcholine (ACh) content as well as acetylcholinesterase (AChE) activity were determined to be significantly downregulated in PFDoA treatment groups. The level of dopamine was upregulated significantly after treating with 1.2 and 6 mg/L of PFDoA. Gene expressions related to the nervous system development were also analyzed, with the exception of the gene mesencephalic astrocyte-derived neurotrophic factor (manf), which is upregulated in the 6 mg/L treatment group. All other genes were significantly downregulated in larvae in the PFDoA group in different degrees. In general, the results demonstrated that PFDoA exposure could result in the disruption of the cholinergic system, dopaminergic signaling, and the central nervous system.

Exposure to PFDoA causes disruption of the hypothalamus-pituitary-thyroid axis in zebrafish larvae

Perfluorododecanoic acid (PFDoA), a kind of perfluorinated carboxylic acid (PFCA) with 12 carbon atoms, has an extensive industrial utilization and is widespread in both wildlife and the water environment, and was reported to have the potential to cause a disruption in the thyroid hormone system homeostasis. In this study, zebrafish embryos/larvae were exposed to different concentrations of PFDoA (0, 0.24, 1.2, 6 mg/L) for 96 h post-fertilization (hpf). PFDoA exposure caused obvious growth restriction connected with the reduced thyroid hormones (THs) contents in zebrafish larvae, strengthening the interference effect on the growth of fish larvae. The transcriptional level of genes within the hypothalamic-pituitary-thyroid (HPT) axis was analyzed. The gene expression levels of thyrotropin-releasing hormone (trh) and corticotrophin-releasing hormone (crh) were upregulated upon exposure to 6 mg/L of PFDoA, and iodothyronine deiodinases (dio2) was upregulated in the 1.2 mg/L PFDoA group. The transcription of thyroglobulin (tg) and thyroid receptor (trβ) were significantly downregulated upon exposure to 1.2 mg/L and 6 mg/L of PFDoA. PFDoA could also decrease the levels of sodium/iodide symporter (nis) and transthyretin (ttr) gene expression in a concentration-dependent manner after exposure. A significant decrease in thyroid-stimulating hormoneβ (tshβ), uridinediphosphate-glucuronosyltransferase (ugt1ab) and thyroid receptor (trα) gene expression were observed at 6 mg/L PFDoA exposure. Upregulation and downregulation of iodothyronine deiodinases (dio1) gene expression were observed upon the treatment of 1.2 mg/L and 6 mg/L PFDoA, respectively. All the data demonstrated that gene expression in the HPT axis altered after different PFDoA treatment and the potential mechanisms of the disruption of thyroid status could occur at several steps in the process of synthesis, regulation, and action of thyroid hormones.

Heavy metal distribution in Tiaoxi River's sediment

According to current study, seven surface sediments and three sediment cores were collected from three typical areas of Tiaoxi River, which were living area, agricultural area, and industrial area. The water quantity into the Lake Taihu from the Tiaoxi River accounted for almost one third of the total water quantity by all rivers into the Lake Taihu. To study geochemical features and pollution history of heavy metals in three typical areas of Tiaoxi River, total content and chemical fractionations of Cu, Pb, Cd, Cr, Mn, Zn, Fe, As, and Hg were analyzed for surface and core sediments using the speciation extraction procedure, proposed by the Commission of the European Communities Bureau of Reference (BCR), together with grain size and organic carbon measurements. The results showed that the concentration of nine heavy metals and the variation characteristics of Zn, Cu, Fe, Mn, and Cr are different among five cores, which has shown that the river responses to natural and anthropogenic activities were dissimilar in various areas. BCR sequential extraction showed contents of Cr, Fe, and Cu were dominated in the remaining parts. Non-residual fractions for Zn and Mn contained major portions. Based on RAC (risk assessment core), the risk of Mn was high to very high in the three typical areas, and the risk of Zn was medium in the three typical areas.

Parental transfer of microcystin-LR induced transgenerational effects of developmental neurotoxicity in zebrafish offspring

Microcystin-LR (MCLR) has been reported to cause developmental neurotoxicity in zebrafish, but there are few studies on the mechanisms of MCLR-induced transgenerational effects of developmental neurotoxicity. In this study, zebrafish were exposed to 0, 1, 5, and 25 μg/L MCLR for 60 days. The F1 zebrafish embryos from the above-mentioned parents were collected and incubated in clean water for 120 h for hatching. After examining the parental zebrafish and F1 embryos, MCLR was detected in the gonad of adults and F1 embryos, indicating MCLR could potentially be transferred from parents to offspring. The larvae also showed a serious hypoactivity. The contents of dopamine, dihydroxyphenylacetic acid (DOPAC), serotonin, gamma-aminobutyric acid (GABA) and acetylcholine (ACh) were further detected, but only the first three neurotransmitters showed significant reduction in the 5 and 25 μg/L MCLR parental exposure groups. In addition, the acetylcholinesterase (AChE) activity was remarkably decreased in MCLR parental exposure groups, while the expression levels of manf, bdnf, ache, htr1ab, htr1b, htr2a, htr1aa, htr5a, DAT, TH1 and TH2 genes coincided with the decreased content of neurotransmitters (dopamine, DOPAC and serotonin) and the activity of AChE. Neuronal development related genes, α1-tubulin, syn2a, mbp, gfap, elavl3, shha and gap43 were also measured, but gap43 was the gene only up-regulated. Our results demonstrated MCLR could be transferred to offspring, and subsequently induce developmental neurotoxicity in F1 zebrafish larvae by disturbing the neurotransmitter systems and neuronal development.

Isotopic fractionation of particulate organic matter and its biogeochemical implication in the littoral zone of Lake Taihu, China

Signatures of stable isotope ratios have previously been used to trace the source and transport of particulate organic matter (POM) in freshwater and marine ecosystems. In this study, water columns were collected at 22 sites in the littoral zone of Lake Taihu in 2014 to investigate the distribution and concentration of nutrients and the stable isotope signatures of POM, and their potential interrelation. Generally, mean concentration of nitrogen forms (NH₄⁺-N) showed substantial variation, probably because they had received large amounts of wastewater from various local industrial enterprises. Source analysis by stable carbon and nitrogen isotopic ratios showed that the main POM sources were phytoplankton. Contrasting correlations were obtained between δ¹⁵N and N concentrations in effluent river mouths when compared with influent river mouths. In effluent river mouths, there was a significant positive correlation between δ¹⁵N and nitrogen concentration (total nitrogen and ammonia-nitrogen), in contrast with the negative correlation in influent river mouths. According to these results, more factors should be taken into consideration when stable carbon and nitrogen isotopes of POM are used to assess the feeding relationship between consumers and prey, as well as the energy flow pathways that support the lake pelagic food webs.

ELS1, a novel MATE transporter related to leaf senescence and iron homeostasis in Arabidopsis thaliana

The multidrug and toxic compound extrusion (MATE) transporters mediate the coupled exchange of organic substrates and monovalent cations have been recently implicated in various plant biological activities. In this work, we isolated a dominant mutant from an Arabidopsis activation-tagging mutant pool. This mutant exhibits pleiotropic phenotype including early flowering, dwarf and bushy architecture, minified lateral organs and early leaf senescence, and is therefore designated early leaf senescence 1-Dominaint (els1-D). Genotyping assays showed that els1-D is a gain-of-function mutant of a novel MATE transporter gene, ELS1, which encodes a close homolog of the previously reported ADP1, BCD1 and DTX50. Further investigations revealed that the overexpression of ELS1 reduces iron content in els1-D, and the accelerated senescence of the detached els1-D leaves can be recovered by exogenous iron supply. In addition, we also found that ELS1 is an iron responsive gene. Based on these findings, we proposed that ELS1 is related to leaf senescence and iron homeostasis in Arabidopsis.

The role of GSH in microcystin-induced apoptosis in rat liver: Involvement of oxidative stress and NF-κB

Microcystins (MCs) are potent and specific hepatotoxins produced by cyanobacteria in eutrophic waters, representing a health hazard to animals and humans. The objectives of this study are to determine the relationship between oxidative stress and NF-κB activity in MC-induced apoptosis in rat liver and the role of glutathione (GSH). Sprague-Dawley rats were intraperitoneally (i.p.) injected with microcystin-LR (MC-LR) at 0.25 and 0.5 LD50 with or without pretreatment of buthionine-(S,R)-sulfoximine (BSO), a specific GSH synthesis inhibitor. MC-LR induced time-dependent alterations of GSH levels in rat liver. Increased malondialdehyde (MDA) and significant changes of antioxidant enzymes including GSH peroxidase (GPX) and GSH reductase (GR) were also observed, particularly at 24 h post-exposure. The results indicated that acute exposure to MC-LR induced oxidative stress, and GSH depletion (BSO pretreatment) enhanced the level of oxidative stress. Furthermore, the modulation of pro-apoptotic gene p53 and Bax and anti-apoptotic gene Bcl-2 was observed in 0.5 LD50 group at 24 h, and the alteration was more pronounced by BSO injection before MC-LR treatment, suggesting that GSH played a protective role against MC-induced toxicity. Additionally, electrophoretic mobility shift assay (EMSA) showed that NF-κB was induced at 0.25 LD50 but inhibited at 0.5 LD50 . The above results indicated that the possible crosstalk of oxidative stress and NF-κB activity was associated with MC-LR-induced hepatocytes apoptosis in vivo. Our data will provide a new perspective for understanding the mechanisms of MC-induced liver injury.

Analysis of point source pollution and water environmental quality variation trends in the Nansi Lake basin from 2002 to 2012

Based on the data analysis of the water environmental quality and economic development from 2002 to 2012 in the Nansi Lake basin, the correlation and change between the water environmental quality and economic development were studied. Results showed that the GDP and wastewater emissions of point source in the Nansi Lake basin had an average annual growth of 7.30 and 7.68 %, respectively, from 2002 to 2012. The emissions of chemical oxygen demand (COD) and ammonia nitrogen (NH3-N) had the average annual decrease of 7.69 and 6.79 % in 2012, respectively, compared to 2002. Basin water quality overall improved, reaching the Class III of the "Environmental quality standards for surface water (GB3838-2002)," in which the main reason was that sewage treatment rate increased gradually and was above 90 % in 2012 (an increase of 10 % compared to 2002) with the progress of pollution abatement technology and the implementation of relevant policies and regulations. The contribution of water environmental pollution was analyzed from related cities (Ji'ning, Zaozhuang, Heze). Results indicated that Ji'ning had the largest contribution to water pollution of the Nansi Lake basin, and the pollutant from domestic sources accounted for a higher percentage compared to industrial sources. The wastewater, COD, and NH3-N mainly came from mining and washing of coal, manufacture of raw chemical materials and chemical products, papermaking industry, and food processing industry. According to the water pollution characteristics of the Nansi Lake basin, the basin pollution treatment strategy and prevention and treatment system were dissected to provide a scientific basis for prevention and control of lakeside point source pollution along the Nansi Lake.

Quantitatively evaluating detoxification of the hepatotoxic microcystin-LR through the glutathione (GSH) pathway in SD rats

Glutathione (GSH) plays crucial roles in antioxidant defense and detoxification metabolism of microcystin-LR (MC-LR). However, the detoxification process of MC-LR in mammals remains largely unknown. This paper, for the first time, quantitatively analyzes MC-LR and its GSH pathway metabolites (MC-LR-GSH and MC-LR-Cys) in the liver of Sprague-Dawley (SD) rat after MC-LR exposure. Rats received intraperitoneal (i.p.) injection of 0.25 and 0.5 lethal dose 50 (LD50) of MC-LR with or without pretreatment of buthionine-(S,R)-sulfoximine (BSO), an inhibitor of GSH synthesis. The contents of MC-LR-GSH were relatively low during the experiment; however, the ratio of MC-LR-Cys to MC-LR reached as high as 6.65 in 0.5 LD50 group. These results demonstrated that MC-LR-GSH could be converted to MC-LR-Cys efficiently, and this metabolic rule was in agreement with the data of aquatic animals previously reported. MC-LR contents were much higher in BSO + MC-LR-treated groups than in the single MC-LR-treated groups. Moreover, the ratio of MC-LR-Cys to MC-LR decreased significantly after BSO pretreatment, suggesting that the depletion of GSH induced by BSO reduced the detoxification of MCs. Moreover, MC-LR remarkably induced liver damage, and the effects were more pronounced in BSO pretreatment groups. In conclusion, this study verifies the role of GSH in the detoxification of MC-LR and furthers our understanding of the biochemical mechanism for SD rats to counteract toxic cyanobacteria.