Anti-Psoriatic Activity of Black, Green and White Tea Extracts from Southeastern China.

Psoriasis is a common chronic inflammatory disease, but most of its current treatments come with a high risk of side effects. As one of the world's top three beverages, tea has a traditional history of being used as a treatment for skin conditions due to its high safety profile, anti-inflammatory and other properties. In this study, we investigated the anti-psoriasis effects of ethanol extracts of black tea, green tea and white tea from southeastern China. The compositions of the tea extracts (TEs) were first determined by UPLC-Q-Exactive-Orbitrap MS and then genetic analysis, antibacterial, anti-inflammatory, and immunocompetence assays were performed. Imiquimod was used to establish a mouse model of psoriasis-like dermatitis and treating with the extracts to examine their efficacy. A total of 88 chemical components, mainly phenols and organic acids, were identified from the TEs. These TEs ameliorated skin damage and they all reduced the expression of cytokines IL-17 and TNF-α. By analyzing the genes, TEs may affect the inflammatory signaling pathway by regulating the metabolic changes. In addition, TEs can significantly scavenge ROS, NO, and inhibit cellular inflammation. In conclusion, this study examined the inhibitory effects of three TEs on psoriasis and their potential as nutritional supplements for the treatment of skin inflammation.

Biomedical relation extraction via knowledge-enhanced reading comprehension.

BACKGROUND: In biomedical research, chemical and disease relation extraction from unstructured biomedical literature is an essential task. Effective context understanding and knowledge integration are two main research problems in this task. Most work of relation extraction focuses on classification for entity mention pairs. Inspired by the effectiveness of machine reading comprehension (RC) in the respect of context understanding, solving biomedical relation extraction with the RC framework at both intra-sentential and inter-sentential levels is a new topic worthy to be explored. Except for the unstructured biomedical text, many structured knowledge bases (KBs) provide valuable guidance for biomedical relation extraction. Utilizing knowledge in the RC framework is also worthy to be investigated. We propose a knowledge-enhanced reading comprehension (KRC) framework to leverage reading comprehension and prior knowledge for biomedical relation extraction. First, we generate questions for each relation, which reformulates the relation extraction task to a question answering task. Second, based on the RC framework, we integrate knowledge representation through an efficient knowledge-enhanced attention interaction mechanism to guide the biomedical relation extraction. RESULTS: The proposed model was evaluated on the BioCreative V CDR dataset and CHR dataset. Experiments show that our model achieved a competitive document-level F1 of 71.18% and 93.3%, respectively, compared with other methods. CONCLUSION: Result analysis reveals that open-domain reading comprehension data and knowledge representation can help improve biomedical relation extraction in our proposed KRC framework. Our work can encourage more research on bridging reading comprehension and biomedical relation extraction and promote the biomedical relation extraction.

Comprehensive copy number analysis of Y chromosome-linked loci for detection of structural variations and diagnosis of male infertility.

Infertility affects about 15% of heterosexual couples and male factors account for ~45-50% of clinical cases. Genetic factors play an important role in male infertility and thus we try to develop a cost-effective method for screening the genetic factors in male infertility. In our retrospective proof-of-concept study, we employed the high-throughput ligation-dependent probe amplification (HLPA) to examine the copy number by 115 genomic loci covering the Y chromosome, and 5 loci covering the X chromosome-specific region. We identified 8 sex chromosome aneuploid people from the low sperm concentration (LSC) group, and Y chromosome-specific microdeletion/duplications in 211 samples from the LSC group, and in 212 samples from the control group. 35 samples showed complete loss of AZFc (BPY2 to CDY1B deletion), which was not observed in controls. Nevertheless, a partial loss of AZFc (BPY2 to BPY2B deletion) was detected at comparable frequencies in both groups (68/211 vs. 108/212, respectively). And we further found structural variations in 28.6 and 26.9% samples from infertility and fertility groups. Moreover, we found that there were lower copy numbers for heterochromatic sequences in men with LSC. Especially, we reported that ultra-low relative copy number (RCN) (<0.5) type and low RCN (0.5 to <0.75) type in Yq12 were more often in the LSC group for the first time. Our results not only shed light on the potential role of low RCN in Yq12 in male infertility but also showed that HLPA can be a powerful and cost-effective tool for clinical screening in male infertility.

Seasonal changes of heavy metals and health risk assessment based on Monte Carlo simulation in alternate water sources of the Xinbian River in Suzhou City, Huaibei Plain, China.

The urban alternate water source (AWS) is of great significance to the sustainable development of the city, the pollution degree, and source of heavy metals (HMs) in AWS, and whether it will adversely affect human health has received widespread attention. In this study, the urban AWS of Xinbian River in Suzhou City, Huaibei Plain, China, was used as the research object to study the seasonal changes of HMs (As, Cr, Cu, Cd, Pb, and Zn), quantitative identification of pollution sources, and human health risks (HHR). Research results show that the contents of those HMs, except As, are less than the drinking standards limit set by the World Health Organization (WHO), and the contents of As, Cr, and Zn are the largest in summer. The multivariate statistical analysis combined with positive matrix factorization (PMF) model analysis revealed that industrial sources accounted for 44.83%, and agricultural sources accounted for 55.17%. HHR assessment based on Monte Carlo simulation shows that the noncarcinogenic risks of adults and children are in the acceptable range (hazardous ingestion (HI) < 1), and the probability of carcinogenic risk values of children and adults are 95.03% and 38.96%, respectively, which are exceed the acceptable range (1 × 10-4) recommended by the United States Environment Protection Agency (USEPA). Approximately 30.75% of the carcinogenic risk value of agricultural source HMs to children exceeds the acceptable range (1 × 10-4). The above research results indicate that the effect of agricultural non-point source pollution on AWS should be prevented.

Source apportionment and natural background levels of major ions in shallow groundwater using multivariate statistical method: A case study in Huaibei Plain, China.

Understanding the sources, natural background levels (NBLs), and threshold values (TVs) of the major ions in groundwater is essential for the effective protection of water resources. In this study, a total of 70 shallow groundwater samples were collected in Suzhou, Huaibei Plain, China. A variety of statistical methods and cumulative probability distribution techniques were performed to identify the sources, NBLs, and TVs of the major ions. The major ion concentrations found in decreasing order as follows: HCO3- > SO42- > NO3- > Cl- and Na+ > Ca2+ > Mg2+. Piper diagram for hydrochemical types shows that groundwater types were Mg-HCO3 (36%), Ca-HCO3 (34%), and Na-HCO3 (30%). According to the factor and the Unmix model analysis, anthropogenic (agriculture-related) and geogenic source (water-rock interactions-related) were identified to be responsible for the chemical composition of the groundwater in the study area, and their mean contributions for the major ion concentrations are 47.9% and 52.1%, respectively. The NBLs for Na+, Ca2+, Mg2+, Cl-, SO42-, and NO3- were determined to be 29.5-44.2, 26.2-38.9, 18.9-39.5, 1.0-9.9, 12.9-19.4, and 2.1-16.5 mg/L, respectively, and the TVs were calculated as 122.1, 169.5, 39.5, 129.6, 134.7, and 18.3 mg/L, respectively. Moreover, this study shows the feasibility and reliability of using these multivariate statistical methods and natural background levels to evaluate the status of groundwater quality.

Drug knowledge discovery via multi-task learning and pre-trained models.

BACKGROUND: Drug repurposing is to find new indications of approved drugs, which is essential for investigating new uses for approved or investigational drug efficiency. The active gene annotation corpus (named AGAC) is annotated by human experts, which was developed to support knowledge discovery for drug repurposing. The AGAC track of the BioNLP Open Shared Tasks using this corpus is organized by EMNLP-BioNLP 2019, where the "Selective annotation" attribution makes AGAC track more challenging than other traditional sequence labeling tasks. In this work, we show our methods for trigger word detection (Task 1) and its thematic role identification (Task 2) in the AGAC track. As a step forward to drug repurposing research, our work can also be applied to large-scale automatic extraction of medical text knowledge. METHODS: To meet the challenges of the two tasks, we consider Task 1 as the medical name entity recognition (NER), which cultivates molecular phenomena related to gene mutation. And we regard Task 2 as a relation extraction task, which captures the thematic roles between entities. In this work, we exploit pre-trained biomedical language representation models (e.g., BioBERT) in the information extraction pipeline for mutation-disease knowledge collection from PubMed. Moreover, we design the fine-tuning framework by using a multi-task learning technique and extra features. We further investigate different approaches to consolidate and transfer the knowledge from varying sources and illustrate the performance of our model on the AGAC corpus. Our approach is based on fine-tuned BERT, BioBERT, NCBI BERT, and ClinicalBERT using multi-task learning. Further experiments show the effectiveness of knowledge transformation and the ensemble integration of models of two tasks. We conduct a performance comparison of various algorithms. We also do an ablation study on the development set of Task 1 to examine the effectiveness of each component of our method. RESULTS: Compared with competitor methods, our model obtained the highest Precision (0.63), Recall (0.56), and F-score value (0.60) in Task 1, which ranks first place. It outperformed the baseline method provided by the organizers by 0.10 in F-score. The model shared the same encoding layers for the named entity recognition and relation extraction parts. And we obtained a second high F-score (0.25) in Task 2 with a simple but effective framework. CONCLUSIONS: Experimental results on the benchmark annotation of genes with active mutation-centric function changes corpus show that integrating pre-trained biomedical language representation models (i.e., BERT, NCBI BERT, ClinicalBERT, BioBERT) into a pipe of information extraction methods with multi-task learning can improve the ability to collect mutation-disease knowledge from PubMed.

[Establishment of a nomogram model to predict systemic inflammatory response syndrome after transrectal ultrasound-guided prostate biopsy].

OBJECTIVE: To access the risk factors of systemic inflammatory response syndrome (SIRS) after transrectal ultrasound-guided biopsy of the prostate (TRUS-Bp) and establish a model and a nomogram for the prediction of SIRS after TRUS-Bp. METHODS: We retrospectively analyzed the clinical data on 752 cases of TRUS-Bp in our hospital from January 2010 to January 2017 and included 570 of the cases in this study. We investigated the independent risk factors for SIRS after TRUS-Bp by univariate and logistic regression analyses, constructed a prediction model and nomogram with the R-Statistics software, evaluated the discrimination of the model with the ROC curve, and measured the conformity by SPSS25.0 Bootstrap sampling. RESULTS: At 1－2 postoperative days, 58 (10.2%) of the 570 patients were diagnosed with SIRS, 22 (3.9%) with bacteremia, and 6 (1.1%) with septic shock, but none died. Logistic regression analysis showed that the independent risk factors for SIRS after TRUS-Bp included old age (>70 yr; OR = 1.1, P = 0.01), high number of biopsy needles (>10; OR = 2.3, P < 0.01), diabetes mellitus (OR = 3.4, P < 0.01), and hypoproteinemia (OR = 2.5, P < 0.01). The area under the ROC curve was 0.947 and internal validation showed a conformity of 92%. CONCLUSIONS: Old age (>70 yr), high number of biopsy needles (>10), diabetes mellitus and hypoproteinemia may increase the risk of SIRS after TRUS-Bp. Evaluation with a model nomogram may help predict the probability of SIRS after TRUS-Bp.

Analysis of Antineutrophil Cytoplasm Antibody from 118 730 Patients in Tertiary Hospitals in Jiangxi Province, China.

BACKGROUND The discovery of antineutrophil cytoplasm antibody (ANCA) makes the early diagnosis of primary vasculitis possible, and also has important guiding significance for the diagnosis and treatment of secondary vasculitis. This study aimed to investigate the clinical significance of ANCA. MATERIAL AND METHODS ANCA was detected by indirect immunofluorescence assay (IIF), and anti-myeloperoxidase (MPO) antibody, and anti-proteinase 3 (PR3) antibody were detected by ELISA. The results were analyzed retrospectively. RESULTS Among 118 730 patients, a total of 5853 (4.93%) were positive for ANCA. In the positive cases, 3.98% were male and 6.33% were female, with significant differences (χ²=123.38, P<0.01). For ANCA, the department with the highest positive rate (15.06%) was the Department of Rheumatology, followed by 7.78% in the Department of Dermatology, 6.79% in the Department of Nephrology, and 5.72% in the Department of Traditional Chinese Medicine (TCM). Anti-PR3 and cANCA were highly specific in primary vasculitis (P<0.01). Anti-MPO and pANCA had high specificity for other autoimmune diseases (P<0.01). CONCLUSIONS ANCA has important guiding significance for vasculitis-related diseases. Therefore, it is important in the diagnosis and treatment of this disease and has value in clinical practice.

The Daphnia magna role to predict the cadmium toxicity of sediment: Bioaccumlation and biomarker response.

To evaluate Daphnia magna role to predict the Cd toxicity in contaminated sediment, the Cd accumulation, metallothionein (MT), and mortality of D. magna exposed to overlying water system or water-sediment coexistence system were measured. The mortality, Cd accumulation, and MT in D. magna increased with the increasing Cd content in sediment. The Cd accumulation and MT in D. magna exposed to the coexistence system were significantly higher than those exposed to the overlying water system because of the ingestion of Cd-containing sediments by D. magna. However, the mortality did not significantly differ in the two systems, suggesting that mortality was less sensitive than accumulation and MT. The Cd accumulation/MT index can explain why the two systems had the similar mortality but different Cd accumulation and MT. Not all the percentage composition of nonresidual fractions (e.g., exchangeable, carbonate bound, and organic bound phases) significantly correlated with the difference values of Cd accumulation and MT, as well as Cd accumulation/MT. However, these indexes increased with the percentage composition of the nonresidual fractions, indicating that the distribution of Cd chemical fractions is crucial for its bioavailability and biotoxicity.

Removal of cadmium and zinc from contaminated wastewater using Rhodobacter sphaeroides.

Rhodobacter sphaeroides was used for bioremediation of wastewater polluted with cadmium (Cd) and zinc (Zn). The tolerance of the microorganism to selected heavy metals (HMs), as well as the effects of pH, temperature and inoculum size on the removal rate, was investigated. The remediation effects of R. sphaeroides were analysed at different initial concentrations of HMs. Bioremediation mechanisms were thoroughly discussed based on the results from the cell characterisation analysis. Cd and Zn could inhibit the growth of R. sphaeroides. However, Cd was more toxic than Zn, with corresponding EC50 values of 5.34 and 69.79 mg L-1. Temperature and pH had greater influence on the removal rate of HMs than inoculum size. The optimal conditions for temperature and pH were 35 °C-40 °C and pH 7, respectively. Initial concentration of HMs and remediation time also affected the removal rate. Rhodobacter sphaeroides had a relatively higher remediation effect under the present experimental conditions. The removal rates for Cd and Zn reached 97.92% and 97.76%, respectively. Results showed that biosorption and HM precipitation were the main bioremediation mechanisms. This information is necessary to better understand the removal mechanism of R. sphaeroides, and is significant for its pilot test and future practical application.

All-fiber tunable laser based on an acousto-optic tunable filter and a tapered fiber.

An all-fiber tunable laser was fabricated based on an acousto-optic tunable filter and a tapered fiber. The structure was of a high signal-to-noise ratio, therefore, no extra gain flattening was needed in the laser. In the experiment, the wavelength of the laser could be tuned from 1532.1 nm to 1570.4 nm with a 3-dB bandwidth of about 0.2 nm. Given enough nonlinearity in the laser cavity, it could also generate a sliding-frequency pulse train. The laser gains advantages of fast tuning and agility in pulse generation, and its simple structure is low cost for practical applications.

Tunable in-fiber Mach-Zehnder interferometer driven by unique acoustic transducer and its application in tunable multi-wavelength laser.

An in-fiber Mach-Zehnder interferometer was proposed and fabricated, which was based on a sandwich-like etched single mode fiber driven by only one acoustic transducer. It succeeded the feature of fast tuning and would not introduce frequency shift in the transmission spectrum. Based on it, a fast tuning dual-wavelength laser with a two-wavelength spacing around 3.5 nm was proved with a tuning range of about 3.6 nm, covering wavelengths from 1561.6 nm to 1568.9 nm.

Mode conversion in a tapered fiber via a whispering gallery mode resonator and its application as add/drop filter.

Based on the conversion between the fundamental mode (LP01) and the higher-order mode (LP11) in a tapered fiber via a whispering gallery mode resonator, an add/drop filter was proposed and demonstrated experimentally, in which the resonator only interacted with one tapered fiber, rather than two tapered fibers as in conventional configurations. The filter gains advantages of easy alignment and low scattering loss over the other filters based on tapered fiber and resonator, and will be useful in application.

Hydrochemical characteristics and quality assessment of deep groundwater from the coal-bearing aquifer of the Linhuan coal-mining district, Northern Anhui Province, China.

There is little information available about the hydrochemical characteristics of deep groundwater in the Linhuan coal-mining district, Northern Anhui Province, China. In this study, we report information about the physicochemical parameters, major ions, and heavy metals of 17 groundwater samples that were collected from the coal-bearing aquifer. The results show that the concentrations of total dissolved solids, electrical conductivity, and potassium and sodium (K(+) + Na(+)) in most of the groundwater samples exceeded the guidelines of the World Health Organization (WHO) and the Chinese National Standards for Drinking Water Quality (GB 5749-2006). The groundwater from the coal-bearing aquifer was dominated by the HCO3·Cl-K + Na and HCO3·SO4-K + Na types. Analysis with a Gibbs plot suggested that the major ion chemistry of the groundwater was primarily controlled by weathering of rocks and that the coal-bearing aquifer in the Linhuan coal-mining district was a relatively closed system. K(+) and Na(+) originated from halite and silicate weathering reactions, while Ca(2+) and Mg(2+) originated from the dissolution of calcite, dolomite, and gypsum or anhydrite. Ion exchange reactions also had an influence on the formation of major ions in groundwater. The concentrations of selected heavy metals decreased in the order Mn > Zn > Cr > Cu > Ni > Pb. In general, the heavy metal concentrations were low; however, the Cr, Mn, and Ni concentrations in some of the groundwater samples exceeded the standards outlined by the WHO, the GB 5749-2006, and the Chinese National Standards for Groundwater (GB/T 14848-93). Analysis by various indices (% Na, SAR, and EC), a USSL diagram, and a Wilcox diagram showed that both the salinity and alkalinity of the groundwater were high, such that the groundwater could not be used for irrigating agricultural land without treatment. These results will be significant for water resource exploiting and utilization in coal mine area.

Mutually modulated cross-gain modulation with a considerable modulation wavenumber-interaction length product.

An extended theory of the mutually modulated cross-gain modulation was developed to make it valid under considerable modulated wavenumber-interaction length product. Parametric analysis of the extended theory shows that, in the modulated probe beam out of the gain medium, the spectral sensitivity of the first harmonic wave is associated with its amplitude. The larger the sensitivity is, the smaller the amplitude will be. An effective method was provided to monitor and achieve high spectral sensitivity at a pre-selected frequency detuning in practice. The validity of the extended theory was confirmed by a sensing experiment in a piece of ∼10-km fiber with 10 kHz modulation frequency, in which a fast light propagation with a sensitivity of 0.592 mrad/kHz was achieved.

Detection of anti-lactoferrin antibodies and anti-myeloperoxidase antibodies in autoimmune hepatitis: a retrospective study.

Anti-lactoferrin antibodies (ALA) and anti-myeloperoxidase antibodies (AMPA) are specific serological markers for autoimmune hepatitis (AIH). The project aimed to detect ALA and AMPA and explore their clinical significances in AIH patients. 59 AIH patients, 217 non AIH patients, and 50 healthy controls were enrolled in this study. ALA and AMPA were detected by ELISA. Antineutropil cytoplasmic antibodies (ANCA) and anti-smooth muscle antibodies (ASMA) were examined by indirect immunofluorescence. Antimitochondrial antibody M2 subtype (AMA-M2), anti-liver kidney microsomal antibody Type 1 (LKM1), anti-liver cytosol antibody Type 1 (LC1), and anti-soluble liver antigen/liver-pancreas antibodies (SLA/LP) were tested by immunoblot. The positivity for ALA was 18.6% in AIH group, only one patient in non-AIH group was positive for ALA; the positivity for AMPA was 59.3% in AIH group, with significant differences (P < 0.01) compared with other groups. The specificities for ALA and AMPA were 99.63% and 97.75%; the sensitivities were 18.64% and 59.32%; and the accuracy rates were 84.97% and 90.80%, respectively. A certain correlation was observed between ALA and SLA/LP, AMPA and ANCA, ASMA in AIH group. ALA and AMPA were associated with AIH, and had high clinical diagnostic value. Co-detection with other relative autoantibodies could play an important role in differential diagnosis of AIH.

Tea for histamine anti-allergy: component analysis of tea extracts and potential mechanism for treating histamine anti-allergy.

In China, Camellia plants are widely used to reduce atopic dermatitis and inflammation-related diseases, but their protective mechanisms remain unclear. This study investigated the anti-allergic dermatitis, anti-oxidation and anti-inflammation effect and underlying mechanism of five Camellia species, including Camellia ptilophylla Chang, Camellia assamica Chang var. Kucha Chang, Camellia parvisepala Chang, Camellia arborescens Chang, and C. assamica M. Chang. A total of about 110 chemical compositions were detected from five Camellia teas extracts. The level of mast cell infiltration in the model mice skin was determined by HE (Hematoxylin and eosin) staining and toluidine blue staining, and the level of interleukin-1ß (IL-1ß) and nerve growth factor was detected by immunohistochemistry. The five Camellia tea leaf extracts have histamine-induced allergic dermatitis. Lipopolysaccharide (Lipopolysaccharide)-induced murine macrophage RAW264.7 inflammation model was found to secrete NF-κB factor, as shown by immunofluorescence, and reactive oxygen species secretion and related cytokine levels were detected. The results suggested that Camellia's five tea extracts had the ability to resist cellular oxidative stress. In addition, the results of cell inflammatory cytokines including fibronectin (FN) and interleukin-6 (IL-6) suggested that the five tea extracts of Camellia had anti-inflammatory effects. Therefore, it is suggested that five Camellia teas may possess inhibitory properties against allergic reactions, oxidative stress, and inflammation, and may prove beneficial in the treatment of allergies.

Clinical effect of different concentrations of ropivacaine in the labor analgesia of dural puncture epidural technique for obese puerperae.

BACKGROUND: This study was performed to analyze the clinical effect of different concentrations of ropivacaine in the labor analgesia of the dural puncture epidural (DPE) technique for obese puerperae. METHODS: One hundred and fifty first-term obese women who received vaginal delivery and required labor analgesia in our hospital were selected prospectively for this study, and divided into groups A, B, and C. The three groups of puerpera were given epidurals with different concentrations of ropivacaine (0.075%, 0.10%, and 0.125%) with sufentanil (0.5 µg/ml) for the labor analgesia regimen. The visual analog scale (VAS), Ramsay scale, and Bromage scale of puerperae before analgesia and at different time points after anesthesia, and analgesic onset time, analgesia time, first PCEA time, PCEA pressing time, ropivacaine consumption, labor time, maternal blood pressure and heart rate, maternal adverse reactions, blood gas analysis in the neonatal umbilical artery, and Apgar score were observed. RESULTS: The analgesia onset time, PCEA pressing time, and ropivacaine consumption in group C were lower and the analgesia time and the first PCEA time were longer than those in groups A and B. At T1-T3 and T5, VAS scores of group A were higher than those in groups B and C, Ramsay score of group A was lower than that of groups B and C at T2-T3, and Bromage score of group C at any time point was higher than other two groups. The time of the second stage of labor in groups B and C was longer than that in group A, which in group C was longer than that in group B. Compared with groups A and C, the blood pressure and heart rate of puerperae in group B were closer to normal values. Three different concentrations of ropivacaine had no significant effect on the umbilical artery blood gas analysis indices and Apgar scores at 1st minute and 5th minute in neonates. The incidence of maternal adverse reactions in group C was lower than those in groups A and B. CONCLUSION: 0.1% ropivacaine combined with 0.5 µg/ml sufentanil through DPE technique has good analgesic efficacy and few adverse effects in obese puerperae.

Evaluation and characterization of biochar on the biogeochemical behavior of polycyclic aromatic hydrocarbons in mangrove wetlands.

As the inter-tidal regions between land and ocean, mangrove ecosystems have high polycyclic aromatic hydrocarbons (PAHs) content, and the over accumulation of PAHs in mangrove wetland poses a serious ecological risk to the health of plant and living creatures. Comparison to the agricultural sources -biochar, biochar produced from wetland plant has lower O/C (molar ratio), larger N contents, higher stability and more benefits. However, whether the rhizosphere action occurs in biochar- amended sediment and how to influence the biogeochemical behavior of PAH have rarely been reported. In this context, a leaching procedure and pot experiment (60-d) were performed on migration and transformation of PAH at the sediment, and toxicity and their bioavailability in plant affected by the presence of Kandelia obovate-derived biochar in Southeast China. Root exudates amendments significantly increased the cumulative leaching-loss of pyrene by 36-51 % with or without biochar amendment via continuous diffusion and partition process, and biochar amendments decreased the bioavailability of pyrene (16.8-25.8 %) probably due to a faster pyrene sorption on inter-phase transport against desorption. The regression analysis indicated a significant relationship (p < 0.05) between leachate pH and pyrene concentrations. Notably, the bioaccumulation of pyrene on K. obovate parts had significant negative correlation (p < 0.05) to biochar. The activities of four key antioxidizes (phenylalanine ammonia-lyase, dismutases, peroxidases and catalases) were significantly decreased with the application of biochar. Moreover, biochar plays a positive role in cytochrome C release and phosphatidylserine secretion, and a combined biochar-rhizosphere approach can improve the stress tolerance and resistance of K. obovate with an enhanced synergetic effect, which could be a feasible remediation strategy for alleviating the mangrove sediment contaminated by PAH.

Environmental geochemical baseline determination and pollution assessment of heavy metals in farmland soil of typical coal-based cities: A case study of Suzhou City in Anhui Province, China.

Soil is the foundation of agricultural green development and human survival; the study of local environmental geochemical baselines can guide soil management and ensure the safe use of soil. In this study, a total of 100 shallow farmland soil samples were collected in each township of Yongqiao District, Suzhou City, Anhui Province, China. Herein, the contents of 10 heavy metal elements including As, Hg, Cd, Pb, Cr, Cu, Mn, Ni, Zn and Fe were determined. In addition, the geochemical baseline of heavy metals was calculated based on the relative cumulative frequency curve method, and the soil pollution status was evaluated. The results show that the average contents of As, Hg, Cd, Cu, Mn and Zn exceeded the soil background values of Anhui Province by 3.82%-64.74% (1.04-1.65 times), meanwhile, the average contents of Pb and Cr were lower than the soil background values of Anhui Province. The average contents of Cd, Cr, Cu, Mn and Ni exceeded the Chinese soil background values by 1.61%-64.74% (0.98-1.65 times). The geochemical baseline values of As, Hg, Cd, Pb, Cr, Cu, Mn, Ni, Zn and Fe were 9.585 mg/kg, 0.028 mg/kg, 0.112 mg/kg, 21.59 mg/kg, 53.66 mg/kg, 19.31 mg/kg, 543.8 mg/kg, 24.93 mg/kg, 50.57 mg/kg and 2.654%, respectively. The pollution assessment results also showed that most of the farmland soil samples in the study area were non-polluting or slightly polluted based on geochemical baselines. Hg and Cu in a few samples were moderately polluted, and Cd in only one sample was moderately intensely polluted. Combined with the distribution of pollution and field investigation, it is considered that Hg comes from atmospheric deposition and agricultural non-point source pollution of industrial pollution. Cu comes from animal husbandry and agricultural pollution. Meanwhile, Cd is related to natural sources, wood processing and agricultural fertiliser application. The study demonstrated that the calculation of soil geochemical background value should take full account of the differences between the various regions, combined with the current state, particularly the pre-consideration of the distribution of elements or pollutants. Then, reasonably select the evaluation standard value so that the evaluation results can truly reflect the state of soil pollution.