XELOX (capecitabine plus oxaliplatin) plus bevacizumab (anti-VEGF-A antibody) with or without adoptive cell immunotherapy in the treatment of patients with previously untreated metastatic colorectal cancer: a multicenter, open-label, randomized, controlled, phase 3 trial.

Fluoropyrimidine-based combination chemotherapy plus targeted therapy is the standard initial treatment for unresectable metastatic colorectal cancer (mCRC), but the prognosis remains poor. This phase 3 trial (ClinicalTrials.gov: NCT03950154) assessed the efficacy and adverse events (AEs) of the combination of PD-1 blockade-activated DC-CIK (PD1-T) cells with XELOX plus bevacizumab as a first-line therapy in patients with mCRC. A total of 202 participants were enrolled and randomly assigned in a 1:1 ratio to receive either first-line XELOX plus bevacizumab (the control group, n = 102) or the same regimen plus autologous PD1-T cell immunotherapy (the immunotherapy group, n = 100) every 21 days for up to 6 cycles, followed by maintenance treatment with capecitabine and bevacizumab. The main endpoint of the trial was progression-free survival (PFS). The median follow-up was 19.5 months. Median PFS was 14.8 months (95% CI, 11.6-18.0) for the immunotherapy group compared with 9.9 months (8.0-11.8) for the control group (hazard ratio [HR], 0.60 [95% CI, 0.40-0.88]; p = 0.009). Median overall survival (OS) was not reached for the immunotherapy group and 25.6 months (95% CI, 18.3-32.8) for the control group (HR, 0.57 [95% CI, 0.33-0.98]; p = 0.043). Grade 3 or higher AEs occurred in 20.0% of patients in the immunotherapy group and 23.5% in the control groups, with no toxicity-associated deaths reported. The addition of PD1-T cells to first-line XELOX plus bevacizumab demonstrates significant clinical improvement of PFS and OS with well tolerability in patients with previously untreated mCRC.

Higher numbers of T-bet(+) intratumoral lymphoid cells correlate with better survival in gastric cancer.

In the present study, we studied the expression of T-bet, a key marker for type 1 immune responses, within the tumor microenvironment of gastric cancer, and analyzed its association with clinicopathological parameters. One hundred and fifty-two archival paraffin-embedded gastric tumor tissues were collected, and the expression of T-bet in these cancer tissue specimens was examined by immunohistochemistry. T-bet(+) tumor-infiltrating lymphocytes (TILs) in some gastric cancer tissues were further characterized by flow cytometric analysis. The density of T-bet(+) TILs in gastric cancer tissues in relation to patient's clinicopathological parameters and postoperative prognosis has been analyzed. Herein, we have found significant increases in T-bet(+) lymphocytes in tumor tissues as compared with normal stomach tissues, gastritis tissues or gastric polyp specimens. T-bet(+) cells mainly consisted of CD4(+), CD8(+) and CD56(+) TILs. In addition, lower numbers of T-bet(+) TILs were associated with poor clinicopathological parameters such as invasion to muscular layer, larger tumor size and advanced cancer stages. Moreover, patients with higher numbers of T-bet(+) TILs have longer disease-free survival and overall survival. Thus, our study supports the idea that tumor growth elicits spontaneous type 1 cellular immune responses and tumor progression is associated with suppression of antitumor immunity. T-bet expression within tumor can serve as a prognostic indicator for gastric cancer and a potential biomarker for immunotherapy.

B7-H4 expression associates with cancer progression and predicts patient's survival in human esophageal squamous cell carcinoma.

A retrospective cohort study including 112 patients suffering from esophageal squamous cell carcinoma (ESCC) was performed to investigate the expression of B7-H4 in ESCC and determine its association with patient's clinicopathological parameters and survival. Expression levels of B7-H4 on tumor cells and densities of tumor infiltrating lymphocytes (TILs) in the surgical specimens of ESCC tissues were characterized using immunohistochemical assays. Uni- and multivariate analyses were performed to evaluate the prognostic value of B7-H4 expression levels and densities of TILs in tumor sections. Positive B7-H4 immunostaining was observed in 107 of 112 (95.5%) of ESCC tissue sections. We further divided all patients into two major subgroups, a lower B7-H4 expression group with 46 patients and a higher B7-H4 expression group with 66 patients. We found that expression levels of B7-H4 on tumor cells were significantly correlated with patient's gender (P = 0.0288), distant metastasis (P = 0.0500), and TNM stage (P = 0.0258). Moreover, tumor cell B7-H4 expression was inversely correlated with densities of CD3(+) T cells in tumor nest (P = 0.0424) and CD8(+) T cells in tumor stroma (P = 0.0229). The overall survival rate of the patients with higher B7-H4 expression was significantly worse than that of the patients with lower B7-H4 expression (P = 0.0105, Hazard Ratio: 1.854, 95%CI:1.152-2.902). Markers of cell-mediated immune responses such as CD3, CD8, and T-bet were associated with better patient survival. The present study demonstrated that B7-H4 expression in human ESCC is associated with cancer progression, reduced tumor immunosurveillance and worse patient outcomes. B7-H4 can serve as a novel prognostic predictor for human ESCC and a potential target for the immune therapy against this malignancy.

Clinical significance and regulation of the costimulatory molecule B7-H3 in human colorectal carcinoma.

B7-H3, a member of the B7-family molecules, plays an important role in adaptive immune responses, and was shown to either promote or inhibit T-cell responses in various experimental systems. B7-H3 was expressed in some human cancers and correlated with poor outcome of cancer patients. However, its exact role in cancer is not known. In the present study, we studied the expression of B7-H3 in the pathologic specimens of 102 patients treated for colorectal carcinoma (CRC) by immunohistochemistry. Strong B7-H3 expression was found in cancer tissues from 54.3% CRC patients, while minimal expression was found in adjacent normal colorectal tissues. Higher B7-H3 expression in tumor positively correlated with a more advanced tumor grade. In addition, consistent with a role of B7-H3 in suppressing tumor immune surveillance, the expression of B7-H3 in cancer cells negatively correlated with the intensity of tumor infiltrating T lymphocytes in both tumor nest and tumor stroma. Furthermore, we found that the level of soluble B7-H3 in sera from CRC patients was higher than healthy donors. TNF-alpha, an important cancer-promoting inflammatory molecule, was subsequently found to significantly increase the release of soluble B7-H3 in colon cancer cell lines. Therefore, our data suggest that both soluble and membranous B7-H3 proteins are involved in colon cancer progression and evasion of cancer immune surveillance.

[Accounting Methods of VOCs Emission Associated with Production Processes in a Fine Chemical Industrial Park].

Volatile organic compounds (VOCs) are one of the key atmospheric pollutants associated with great impact on air quality. Industrial sources have become the most important source of VOCs emissions in China, of which the chemical industry accounts for a large part. At present, more than half of chemical manufacturers are clustered in chemical industrial parks (CIPs), thus the control of VOCs in CIPs is crucial. This study analyzed the production processes of the fine chemical industry and the principle of VOCs production, and then proposed an accounting model of VOCs emissions associated with production processes, based on a typical fine chemical industrial park:Hangzhou Bay Shangyu Economic and Technological Development Area (HSEDA). The quantity of VOCs generation in the main production processes, such as feeding, heating, chemical reaction gas take-off, cleaning, vacuum pumping, pressure release, and evaporating, were calculated. Meanwhile, the chemical process simulation software Aspen was also employed to simulate the VOCs generation in these processes. The methods were applied to 14 representative products in HSEDA and the feature of VOCs generation in the chemical processes mentioned above, and components were revealed. The results of the two methods were compared, and the difference between the two methods was within±22% except for the pressure release process. The model and accounting methods proposed in this study will have sound applicability in accounting for VOCs emissions in fine chemical industrial parks underpinned by quantitative chemical industry production parameters.

Clinical significance of IFIT2 expression in human renal cancer tissues.

BACKGROUND: Interferon (IFN)-induced protein with tetratricopeptide repeats 2 (IFIT2) is an important member of the IFN-stimulated gene (ISG) family. It has been demonstrated that IFIT2 is important in the physiopathological processes of antiviral and antitumor activities. We previously demonstrated that IFIT2 was highly expressed in paracarcinoma tissues compared with gastric cancer tissues, and its expression level was positively correlated with a superior postoperative prognosis of the patients. METHODS: We performed immunohistochemical staining of IFIT2 in human clear cell renal cell carcinoma (ccRCC) tissues by using a tissue microarray. RNAseq data of kidney clear cell carcinoma (KIRC) samples from The Cancer Genome Atlas (TCGA) were used to perform the enrichment analyses based on the genes that were highly correlated with IFIT2. RESULTS: Weak staining of IFIT2 was located on the cytoplasm and cell membrane surface of the cancer cells, while positive staining of IFIT2 was located mainly on adjacent normal tissues. Survival analysis showed that patients with higher IFIT2 expression had better overall survival than patients with lower IFIT2 expression (P=0.030). The Cox model further demonstrated that age (P=0.002), pathological stage (P=0.000), TNM stage (P=0.005) and IFIT2 expression (P=0.003) could be used as independent prognostic predictors for ccRCC patients. Additionally, the enrichment analysis based on ccRCC expression profile data extracted from TCGA revealed that the genes highly correlated with IFIT2 were mainly related to the biological processes of virus response, T cells and the innate immune response (GO:0009615, GO:0042110, and GO:0045088) and the pathways of NLR signaling, chemokine signaling, and TLR signaling (hsa04621, hsa04062, and hsa04620). CONCLUSIONS: IFIT2 could serve as a potential prognostic marker for ccRCC patients, and the mechanism of decreased IFIT2 expression in the progression of ccRCC merits further investigation.

[Nitrification and Bioaugmentation of Biological Treatment System of Sewage Treatment Plant at High Temperature in Summer].

The influence of temperature (30-45℃) and ammonia-nitrogen volume load on the nitrification function and microbial community of activated sludge in an aerobic tank of a sewage treatment plant were investigated under simulated high-temperature stress in the summer. Meanwhile, the bioaugmentation effectiveness of the middle-temperature-enriched nitrifying sludge (with or without acclimation) was evaluated in two biological treatment systems under high-temperature shock. The results showed that the ammonium-nitrogen (NH4+-N) removal efficiency and the nitrifying bacteria content of the aerobic activated sludge at 30-40℃ were above 90% and up to 4.55% and decreased to 40% and 1.97% at 45℃, respectively. To quickly recover the nitrification function of the biological system under high-temperature shock in the summer, the middle-temperature-enriched nitrifying sludge was acclimated at 40℃ for 61 d and achieved (60±5) mg·(L·h)-1 nitrification activity. Then, its bioaugmentation efficiency was compared with that of the middle-temperature-enriched nitrifying sludge. In the bioaugmentation test, 10% of NH4+-N was removed in the reactor inoculated with 5% (volume fraction) of the acclimated nitrifying sludge, while the reactor needed inoculate with 10% (volume fraction) of the middle-temperature-enriched sludge to achieve the same removal efficiency. The results suggested that middle-temperature-enriched nitrifying sludge, after acclimating at 40℃, has a better enhancement effect under a high-temperature shocking load.

microRNA-181b suppresses the metastasis of lung cancer cells by targeting sex determining region Y-related high mobility group-box 6 (Sox6).

BACKGROUND: The aim of the study was to measure the expression of microRNA (miR)-181b in patients with lung cancer, investigate its biological function and elucidate the underlying mechanisms associated with the development of lung cancer. METHODS: miR-181b expression in tissues was measured via RT-qPCR. After A549 cells were transfected with miR-181b mimic or si-Sox6, the proliferation, migration and cell cycle distribution of A549 were evaluated using cell counting kit-8 assay, transwell assay and flow cytometry. The levels of cell cycle-related proteins and Sox6 were analyzed by western blotting. Gene targets of miR-181b were predicted via bioinformatics analysis and verified using a dual-luciferase reporter gene assay. RESULTS: Expression of miR-181b was significantly downregulated in lung cancer tissues (P < 0.05), and was inversely correlated with the degree of cell differentiation and clinical stages of lung cancer (both P < 0.05). Additionally, the expression of miR-181b was significantly lower in adenocarcinoma compared with squamous cell carcinoma in the lungs (P < 0.05). Overexpression of miR-181b significantly decreased the protein level of Sox6 and significantly suppressed the cell proliferation and metastasis (both P < 0.05); this effect was also observed in A549 cells transfected with si-Sox6. The luciferase activity of a Sox6 3'-untranslated region-based reporter construct was significantly lower when transfected with miR-181b (P < 0.05), which suggests that Sox6 is a direct target of miR-181b. CONCLUSION: The results of the present study suggest that miR-181b may function as a tumor inhibitor in the development of lung cancer via targeting Sox6 to decrease the proliferation and metastasis of lung cancer cells.

[Distribution Characteristics of Antibiotic Resistance Genes in Wastewater Treatment Plants].

Wastewater treatment plants (WWTPs) are regarded as the main source for antibiotic resistant genes (ARGs). To explore the features regarding the distribution of ARGs in wastewater with complicated composition in treatment plants, wastewater samples from a chemical industry park that produced antibiotics were selected. qPCR was applied to detect the type and abundance of ARGs in the wastewater flows from the WWTPs. The results indicated that 16 types of ARGs were detected from the wastewater from the WWTPs, among which sulfonamide resistance genes and tetracycline resistance genes were the dominant ARGs that appeared in the wastewater. Additionally, intI 1 was detected and its abundance was correlated with that of sulfonamide resistance genes. This indicated that intI 1 may promote the migration and transformation of sulfonamide resistance genes. The pharmaceutical factories in the park mainly synthesize macrolide antibiotics. Because of the selective pressure, the absolute abundance of ermB in the wastewater was much higher than that in the other industrial wastewater. The total ARGs decreased by 1.16 log via traditional biological treatment process, and the total ARGs decreased by 2.46 log via the Fenton process. The results showed that the removal effects of deep treatment processes on ARGs were better than that of biological treatment in this wastewater treatment process. Highly abundant and movable ARGs already exist in the water body, and their release from WWTPs without effective treatment poses high risks to the environment.

[Removal and Influence of Ciprofloxacin in a Membrane Bioreactor].

A membrane bioreactor (MBR) was used to treat ciprofloxacin (CIP)-contaminated artificial wastewater. The pollutant removal performance and the microbial community structure of the MBR were studied at three different CIP dosages (0 mg·L-1, 5 mg·L-1, and 10 mg·L-1). The results showed that the sludge concentration in the reactor decreased and then levelled off as the dosage of CIP was increased from 0 mg·L-1 to 5 mg·L-1 and further to 10 mg·L-1. The mean removal of TOC and COD decreased from 98.40% and 97.80% to 84.20% and 94.10%, respectively, indicating that the CIP negatively influenced the organic removal but the effect was minor. In contrast, the ammonium removal was greatly influenced by the dosage of CIP. When the CIP dosage increased from 0 mg·L-1 to 5 mg·L-1 and further to 10 mg·L-1, the ammonium removal efficiency decreased from 96.91% to 84.14% and then to 77.80%, and the activity of Nitrosomonas, Alcaligenes, Nitrospira, and Nitrobacter were greatly inhibited. The CIP removal initially increased and then decreased. The mass balance revealed that the removal of CIP in the MBR was principally attributed to biodegradation and sludge adsorption, which accounted for 30.13% and 0.25%, respectively, at a CIP dosage of 5 mg·L-1 and 7.55% and 1.81% at a CIP dosage of 10 mg·L-1.

[Ozone-Biological Activated Carbon for Advanced Removal of Typical Persistent Organic Pollutants from Micro-Polluted Source Water in the Yangtze Delta Region].

Ozone-biological activated carbon (O3-BAC) was studied for the advanced removal of organics from micro-polluted source water in the water supply plant P located in J City in the Yangtze Delta Region. The results show that 19.2% of the permanganate index, 10.4% of total organic carbon, and 23.0% of UV254 were removed by the advanced treatment of O3-BAC. Eight types of polycyclic aromatic hydrocarbon (PAH), 16 types of organochlorinated pesticides (OCPs), and five types of haloacetic acids (HAAs) were detected in the source water. The total concentrations were 53.9-100.0, 6.5-41.8, and 2.5×103-1.1×104 ng·L-1, respectively. The advanced O3-BAC treatment removed 32.5% of PAHs and 25.9% of OCPs, greatly improving the effluent of the conventional water supply process. However, HAAs were mainly removed with the conventional process, with a removal rate of 33.8%-87.0%. After the advanced treatment with O3-BAC, the amount of chloroacetic acid slightly decreased, while the concentration of bromoacetic acid slightly increased.

AOX contamination in Hangzhou Bay, China: Levels, distribution and point sources.

The parameter AOX (adsorbable organic halogens) indicates the total amount of organic halogens in an environment. Seawater and surface sediment samples from 12 sample sites in the Hangzhou Bay (HZB), China, were analyzed for AOX to investigate its contamination status. In this study, the AOX concentration ranged from 140.6 ±â€¯45.6 µg/L to 716.1 ±â€¯62.3 µg/L in seawater of the HZB, and from 11.3 ±â€¯2.4 mg/kg to 112.7 ±â€¯7.2 mg/kg in the sediment. Ocean currents, fluvial currents and the Yangtze River exerted profound influences on the distribution of AOX in the HZB. The point sources around the HZB, represented by wastewater treatment plants, discharged at least 645.4 t AOX into the HZB every year, most of which was generated by industrial activities rather than the human daily activities.

[Distribution and Removal of Antibiotic Resistance Genes in Two Sequential Wastewater Treatment Plants].

Wastewater treatment plants (WWTPs) have been regarded as important point-sources of antibiotic resistance genes (ARGs) in aquatic environments. To investigate the distribution and removal of ARGs in WWTPs, a pharmaceutical wastewater treatment plant (PWWTP) and an integrated wastewater treatment plant (IWWTP) in a fine-chemical industrial park were chosen, and polymerase chain reaction (PCR) and real-time PCR techniques were used to determine the occurrence and abundances of ARGs along the treatment processes. Ten and fifteen ARGs were detected initially in the influents of PWWTP and IWWTP respectively, in which tetracycline and sulfonamide resistance genes were frequently reported, while dfrA13 was first reported in WWTPs. The most abundant ARGs in the influents were sul Ⅰ and sul Ⅱ, followed by dfrA13, tetQ, floR, tetO, and tetW. The total ARGs increased by 0.21 log after the treatment by PWWTP, whose effluent contributed 0.87% to the inflow yet 5.05% to the total ARGs of IWWTP. Finally the total ARGs removed by IWWTP was 1.03 log, with the remaining ARGs then transported within the final effluent to the nearby coastal area. The authors concluded that the environmental and other impacts from the spread of ARGs on the microbial communities of the coastal environment needed further study.

[Pilot-scale Experiment on Enrichment of Nitrifying Activated Sludge and Its Application in Enhancing a Wastewater Biological Treatment System Against Ammonia Shocking Loads].

Nitrifying activated sludge (NAS) was enriched in a membrane bioreactor (MBR) with pre-treated municipal wastewater and additional ammonium sulfate as the culture medium. The influences of temperature, dissolved oxygen (DO), ammonia nitrogen volumetric load, free ammonia (FA), and free nitrite (FNA) on the enrichment of NAS were investigated, the cost of the process was evaluated, and then NAS's application in enhancing a wastewater biological treatment system against ammonia shocking loads was attempted. The results showed that after 182 days of cultivation in an MBR, NAS had a nitrification activity of 98.41 mg·(L·h)-1, which was 30-times higher than that of the seeding sludge. The yield of NAS was 14.96 mg·(L·d)-1, costing 3.52 Yuan for 1 kg. Temperature was found to be a key factor affecting the sludge nitrification activity. The sludge nitrification activity was decreased to 1/3 of the maximum value at temperatures below 15.0℃, while lowering the ammonium volumetric load retarded the decrease in the sludge nitrification activity to some extent. In addition, dissolved oxygen deficiency resulted in nitrite accumulation, and thereby slowed down the NAS enrichment rate. The enriched NAS was then applied to a wastewater biological treatment pilot equipment, which had just been exposed to an ammonium shocking load. The removal rate of ammonia nitrogen in the biological system increased from 29.4% to 88.4% after 2.0% of NAS was inoculated. The enhanced biological system retained ammonia removal rates of as high as 99.0%, even as the temperature dropped to 13.3℃±1.6℃ afterwards. The above pilot-experiment results suggested that enriched nitrifying sludge is suitable for quickly increasing the start-up or recovery rates of the nitrifying function in a biological system.

[Influence of Ciprofloxacin on the Microbial Community and Antibiotics Resistance Genes in a Membrane Bioreactor].

A membrane bioreactor (MBR) was used to treat ciprofloxacin (CIP)-contaminated artificial wastewater. The microbial community structure and the abundance of antibiotic resistant genes (ARGs) in the MBR were studied at four CIP dosages (0, 5 mg·L-1, 10 mg·L-1, and 15 mg·L-1). The results showed that Proteobacteria and Bacteroidetes remained the dominant phylum, with relative abundances of 57.5% and 12.7%, respectively, as the dosage of CIP was increased from 0 mg·L-1 to 15 mg·L-1. Rhodocyclaceae, Chitinophagaceae, and Comamonadaceae became the dominant family with abundances of 29.96%, 5.44%, and 6.60%, respectively. Methyloversatilis, Ferruginibacter, Zoogloea, and Comamonas became the dominant genus, with relative abundances of 21.70%, 7.56%, 5.24%, and 4.15%, respectively. The decrease of Chao1, ACE, and Shannon and the increase of Simpson indicated a decrease in microbial abundance and diversity. The relative abundances of Nitrosomonas, Nitrospira, Alcaligenes, and Nitrobacter decreased, which caused a decrease in the NH3-N removal rate. A CIP-ARGs analysis revealed that the relative abundances of gyrA, gyrB, and parC were increased, beginning after the sludge was dosed with 5 mg·L-1of CIP for 33 days, which augmented the risk for microbial drug-resistance.

[Life Cycle Assessment of Traction Lead-acid Batteries for Electric Bikes in China].

This research undertook a life cycle assessment (LCA) for lead-acid batteries (LABs) used in electric bikes, the fastest growing LABs in China. A cradle-to-grave LCA model was established to identify the key materials or processes that contribute most to environmental impacts within the life cycle of LABs, including material production, battery manufacture, transportation, use, and end-of-life. A large amount of primary data obtained from enterprisers and a Chinese LCA database were used in this research to reflect the status of technology and environmental management for the related industries in China. The results indicate that material production and LAB use dominate in resource consumption and environmental impacts during the life cycle of LABs. Material production is the most important driver of such impacts as abiotic resources depletion (699%), eutrophication (89%), photochemical smog production (98%), ozone depletion (117%), total human toxicity (159%), and ecological toxicity (484%). Battery use is responsible for 83% of primary energy use and contributes the highest potentials to the impacts related to energy, including global warming potential (86%) and acidification potential (70%). Recovery of materials at the end-of-life stage will significantly mitigate the overall life cycle impacts by reducing virgin material consumption. Based on the findings, there are several substantial opportunities to reduce the overall environmental impacts of batteries, such as prolonging the lifetime of batteries, reducing the metal consumption in batteries, and improving the technology and management in recovery of end-of-life batteries.

[Coking Wastewater Treatment Efficiency and Comparison of Acute Toxicity Characteristics of the AnMBR-A-MBR and A2-MBR Processes].

Coking wastewater contains high-strength refractory organic pollutants and is commonly treated by biological treatment processes. To improve the efficiency of biological treatment, two laboratory scale processes, anaerobic membrane bioreactor/anoxic/aerobic membrane bioreactor (AnMBR-A-MBR) and anaerobic/anoxic/aerobic membrane bioreactor (A2-MBR), were developed for coking wastewater treatment. The removal of main pollutants and the stability of different pollutant loadings were compared under the optimum operating conditions. Acute toxicity distribution, variations, and toxic matter characteristics of the two processes were investigated by solid-phase extraction, components separation, the luminous bacteria Q67 test, and three-dimensional fluorescence spectrometry. The results showed that the organic pollutant removal rate of AnMBR was 15.3%, which was significantly higher than the anaerobic stage of the A2-MBR system (3.4%), and the AnMBR-A-MBR system had greater resistance to pollutant loading. Acute toxicity of AnMBR-A-MBR system in each stage effluent was lower than the A2-MBR system and the total toxic unit removal rate of both were 85.2% and 79.2%, respectively. The acute toxicity of the polar component in each stage effluent was the highest, and the polar and mid-polar components contributed to the majority of the toxicity. The toxicity of each stage effluent mainly originated from Region Ⅱ aromatic protein analogues, which could be the main acute toxicity substances of the polar component.

[Cultivation of Spirulina platensis in Digested Piggery Wastewater Pretreated by SBR with Operating Conditions Optimization].

Digested piggery wastewater(DPW) contains high concentrations of nitrogen and phosphorus which could be used as a cost-effective culture medium for Spirulina platensis. However, Spirulina platensis would be limited by many factors in the complex composition of DPW, especially the high concentration of ammonium. In this paper, a traditional sequencing batch reactor(SBR) was used to remove these inhibitors in DPW. The retention of nitrate and nitrite in the effluent, which was used as nitrogen source for cultivating Spirulina platensis, was studied at different ratios of chemical oxygen demand(COD) to total nitrogen(TN) in the influent. By comparing the growth of Spirulina platensis in the related effluents, the operation condition of SBR was optimized. The lab-scale cultivation results showed that Spirulina platensis possessed a high biomass yield of 0.084 g·(L·d)-1 in the effluent when the COD/TN ratio of SBR influent was 3.0. In particular, the concentrations of ammonium, nitrate and nitrite in the effluent were 51.2 mg·L-1, 91.6 mg·L-1and 213.1 mg·L-1, respectively. Furthermore, the aforementioned effluent was also used to culture Spirulina platensis in a 120 L outdoor raceway pond, and the growth rate of Spirulina platensis reached(0.075±0.003)g·(L·d)-1 after 10-day culture. The protein content of Spirulina platensis was approximately 60% and the removal efficiency of ammonium was 99%. This study provides an alternative method for the utilization of DPW.

[Abundance of Cell-associated and Cell-free Antibiotic Resistance Genes in Two Wastewater Treatment Systems].

For revealing the characteristics of antibiotic resistance genes (ARGs) in wastewater treatment systems, real-time PCR was adopted to investigate the variation of abundances of cell-associated ARGs and cell-free ARGs, in a municipal wastewater treatment system (M for short) and a coking wastewater treatment system (C for short). In system M, the absolute abundances of the cell-associated ARGs, sul Ⅱ,tetC,blaPSE-1, and ermB, were much higher than those of the cell-free fractions in the influent. The biological treatment process did not enrich antibiotic resistance bacteria (ARBs) and membrane filtration of the MBR effectively reduced both cell-associated and cell-free DNA in water. The total ARGs removal was 2.54-4.95 logs. In system C, the biological treatment process enriched the sul Ⅱ -carried ARBs; however, the relative and absolute abundances of cell-free sul Ⅱ were decreased. The succeeding process, coagulation-sand filtration, decreased the absolute abundance of cell-associated sul Ⅱ, but increased the absolute abundance of cell-free sul Ⅱ in water. The proportion of cell-free sul Ⅱ in total sul Ⅱ gene increased from 0.05% in the biological treatment effluent to 1.33% in the sand filtration effluent and further increased to 9.31% after the effluent was kept at 25℃ and at dark for five days. The ratio of cell-free ARGs to total ARGs increased with deep removal of ARBs and lysis of residual cells. The risk of ARG proliferation by cell-free DNA in the effluent needs further evaluation.

[Performance of Nanofiltration for Improving the Drinking Water Quality in a Water Supply Plant with Micropolluted Water Resource].

Four nanofiltration membranes connected in series were used for improving the drinking water quality in a water supply plant in south China with micropolluted water resource. The performance of the nanofiltration for improving the drinking water quality was investigated. The results showed that nanofiltration was efficient for removal of both traditional water pollution indicators and organic toxicants. More than 95% of TOC and UV254 were removed from the effluent of the traditional water purification process in the water supply plant. The NF effluent had a TOC of no higher than 0.3 mg·L-1 and a UV254 of below 0.005 cm-1. The removal rates of haloacetic formation potential,trihalomathanes formation potential, polycyclic aromatic hydrocarbon(PAHs)and organochlorinated pesticides(OCPs)were 62%, 85%, 50% and 95%, respectively. Genotoxicity of the NF effluent was undetectable in the umu-SOS test. Moreover, no significant difference was observed in the organic pollutants removal of haloacetic formation potential,trihalomathanes formation potential and OCPs among the four NF membranes but in the removal of PAHs with relatively smaller molecular weight. Nanofiltration showed higher removal rate of high-molecular-weight organic matters over low-molecular-weight organic matters. By comparison, only 17% of PAHs, 62% of OCPs and 80% of genotoxicity were removed by advanced treatment of ozone (O3) followed by treatment with biological activated carbon (BAC) in this water plant, indicating that nanofiltration was better for removal of organic pollutants.