ABSTRACT
Most of the materials studied as catalysts in the electro-Fenton system are variants of iron oxide or iron hydroxide. However, iron-based catalysts often exhibit weak catalytic capabilities under neutral and alkaline conditions. In this work, we synthesized three cobalt based bimetallic oxides, Co2CuOx, Co2AlOx, and Co2NiOx, using hydrothermal method and evaluated them as catalysts for the heterogeneous electro-Fenton system to remove 1-hydroxyethylidene-1,1-diphosphonic acid (HEDP) and Methylisothiazolinone [2-methyl-4-isothiazolin-3-one] (MIT). Co2NiOx has the highest catalytic degradation activity for HEDP, and Co2CuOx has the best catalytic degradation effect for MIT. Based on characterization results of the catalysts, the reasons for the differences in the pollutant removal efficiency were analysed, and the optimal pH for the three cobalt based oxides to remove HEDP and MIT was investigated. The results showed that the optimal pH values of the three cobalt based bimetallic oxides are not only influenced by the second metal type, but also by the properties of pollutants. Therefore, suitable cobalt based catalysts can be selected based on the different properties of pollutants, or the composition of cobalt based catalysts can be adjusted to meet the different pH requirements of target wastewater. The three cobalt based bimetallic oxides exhibited good degradation of HEDP and MIT under neutral conditions, which to some extent solved the problem of narrow pH range in the practical application of the electro-Fenton process.
ABSTRACT
Heterogeneous electro-Fenton is one of the promising technologies to degrade refractory organic phosphonates. In this work, CoNWs@CoAl-LDHs/Fe3O4 and CoNPs@CoAl-LDHs/Fe3O4 were successfully synthesized by a co-precipitation method and applied to degrade 1-hydroxyethane-1,1-diphosphonic acid (HEDP) and glyphosate (PMG) via an electro-Fenton process. The results indicated that the removal rate of HEDP (100 mg L-1) and PMG (100 mg L-1) by CoNWs@CoAl-LDHs/Fe3O4 increased from 62.09% and 95.31% to 82.45% and 100%, respectively. The CoNPs@CoAl-LDHs/Fe3O4 electro-Fenton system could remove 70.03% of HEDP and nearly 100% of PMG within 2 hours at a pH of 3. Moreover, we compared the SEM, EDS, XRD and BET results of CoNWs@CoAl-LDHs/Fe3O4 with those of CoNPs@CoAl-LDHs/Fe3O4. The effects of initial pH, CoNW dosage and reaction time on the degradation of HEDP and PMG were discussed. CoNWs@CoAl-LDHs@Fe3O4 could even remove 71.03% of HEDP at a neutral pH. After four cycles of repeated use at a pH of 3, the removal rate of HEDP by CoNWs@CoAl-LDHs/Fe3O4 was still higher than 70%. Radical quenching experiments revealed that ËOH is the dominant active species participating in the heterogeneous electro-Fenton process. Finally, we would talk about the mechanism of the CoNWs@CoAl-LDHs/Fe3O4-based electro-Fenton system.
ABSTRACT
Two novel adsorbents (LDH@GO-NH2 and LDH@GO-SH) were successfully synthesized by grafting thiol- or amino-functionalized GO onto LDH and their adsorption capacities for heavy metal ions (Cu(II) and Cd(II)) were significantly enhanced. Characterization experiments illustrated that the thiol group (-SH) or amino group (-NH2) was grafted onto LDH@GO-NH2 or LDH@GO-SH. Adsorption isotherms were satisfactorily fitted by both Langmuir and Freundlich models. The maximum adsorption capacity of Cd(II) on LDH@GO-SH at 308 K was 102.77 mg/g, which was about triple that of LDH@GO-NH2. The enhancement in adsorption capacity of LDH@GO-SH was due to the cooperative effect of LDH and GO-SH. The kinetic experimental data for LDH@GO-NH2 and LDH@GO-SH were found to be in good agreement with the pseudo-second-order model. The thermodynamic parameters calculated from the temperature-dependent adsorption isotherms indicated that the adsorption was spontaneous and an endothermic process. The possible adsorption mechanisms comprising formation of precipitation, isomorphic substitution of Mg(II), and formation of complexation with amino groups or thiol groups were proposed. Desorption experiments put into evidence that LDH@GO-NH2 and LDH@GO-SH may be promising suitable candidates for the remediation of metal ions from aqueous solutions in real work in the near future.
Subject(s)
Metals, Heavy , Water Pollutants, Chemical , Adsorption , Cadmium/analysis , Kinetics , Water Pollutants, Chemical/analysisABSTRACT
[This corrects the article DOI: 10.1098/rsos.191304.].
ABSTRACT
OBJECTIVES: Serum 14-3-3η is a novel joint-derived proinflammatory mediator associated with rheumatoid arthritis (RA). This study aimed to evaluate the diagnostic capacity of serum 14-3-3η and its correlation with clinical variables in patients with RA. METHODS: A total of 94 patients with RA and 80 age- and sex-matched controls, including 40 healthy subjects, were included. Serum 14-3-3η levels were assessed by quantitative enzyme-linked immunosorbent assay. Receiver-operating characteristic (ROC) curves analysis was used to determine the sensitivity and specificity of 14-3-3η. Spearman's rank correlation coefficient was used to assess the relationship between 14-3-3η and other clinical measures in patients with RA. RESULTS: Median (interquartile range) of serum 14-3-3η concentration (ng/ml) in RA patients (2.34 [1.56-3.39]) was significantly higher than that in healthy subjects (0.17[0.11-0.30]) and disease controls (1.66[1.21-2.74]; P<0.05). ROC curve analysis comparing patients with RA with all controls demonstrated a significant (P<0.001) area under the curve (AUC) of 0.81 (95% confidence interval: 0.74-0.88). At a cutoff of 1.44 ng/mL, the ROC curve yielded a sensitivity of 78.7% and specificity of 73.8%. The sensitivity of anti-citrullinated protein antibody (ACPA) and rheumatoid factor (RF) were 84.0% and 72.3%, respectively. Adding 14-3-3η to ACPA and/or RF discriminated more than 96% of patients with RA. The positive rate of at least one of the three markers was up to 99%, with a specificity of about 70%. The results of correlation analyses revealed that serum levels of 14-3-3η protein positively correlated with C-reactive protein (r=0.250, P<0.05), erythrocyte sedimentation rate (r=0.294, P<0.01), and 28-joint disease activity score (r=0.275, P<0.05) in patients with RA. CONCLUSIONS: 14-3-3η protein is a novel marker that can apparently enhance the detection rate of patients with RA. The level of serum 14-3-3η protein correlates to some degree with disease activity.
Subject(s)
14-3-3 Proteins/blood , Arthritis, Rheumatoid/blood , Arthritis, Rheumatoid/diagnosis , Biomarkers/blood , Severity of Illness Index , Case-Control Studies , Disease Progression , Female , Humans , Male , Middle Aged , ROC CurveABSTRACT
The electro-Fenton (EF) process was applied to treat mother liquor of gas field wastewater (ML-GFW). The Fe-Fe electrodes were used and H2O2 was added to the EF system. Effect of initial pH on chemical oxygen demand (COD) removal efficiency, specific electrical energy consumption (SEEC), specific electrode plate consumption (SEPC) and organic matter removal mechanism was investigated. The results showed that COD removal efficiency reached the maximum (71.9%) at initial pH of 3 after reaction for 3 h. Besides, considering with the SEEC and SEPC, pH of 3 was also the best choice, at which SEEC was 4.7 kW h kgCOD -1, SEPC was 0.82 kgFe kgCOD -1. Organic matter removal was achieved by two ways: oxidation and flocculation, and oxidation played a major role. With the analysis of GC-MS, the possible degradation pathways of the representative contaminants in the ML-GFW were given.
ABSTRACT
Cd(ii) adsorption onto Fe(ii) modified Layered double hydroxide-graphene oxide (LDH-GO@Fe(ii)) was investigated using batch experiments. With the modification of Fe(ii), LDH-GO maintained its structure, while Fe(ii) species formed non-crystalline iron oxide clusters on the surface of the LDH/GO. A kinetics study indicated that adsorption obeyed a pseudo-second-order rate law. The equilibrium data were fitted well with the Langmuir isotherm model. The maximum adsorption capacity of LDH-GO@Fe(ii)10 was 28.98 mg g-1, higher those that of pure LDH-GO and LDH-GO@Fe(ii)50. The increased sorption capacities could be explained by the increased specific surface area. Modification with Fe(ii) would lead to the generation of amorphous Fe oxides and Fe could occupy the binding sites for Cd(ii), thus excess Fe in the structure will restrain the adsorption of Cd(ii). The XRD and XPS patterns revealed the formation of Cd(OH)2 after adsorption. Batch experiments indicated that precipitation and surface complexation were the main pathways for Cd(ii) removal.
ABSTRACT
A lab-scale aerobic-anoxic-aerobic (AE1-AN-AE2) MBBR system was tested for the removal of COD,
Subject(s)
Bioreactors , Coal , Industrial Waste/analysis , Nitrogen/chemistry , Wastewater , Denitrification , Membranes, Artificial , Waste Disposal, FluidABSTRACT
Fracturing waste liquid (FWL) is generated during shale gas extraction and contains high concentrations of suspended solid, salinity and organic compounds, which needs proper management to prevent excessive environmental disruption. Biological treatment of the FWL was attempted in this study using a membrane-coupled internal circulation aerobic biological fluidized bed (MC-ICABFB) after being treated by coagulation. The results showed that poly aluminum chloride (PAC) of 30â g/L, polyacrylamide (PAM) of 20â mg/L and pH of 7.0 were suitable choices for coagulation. The pretreated FWL mixed with synthetic wastewater at different ratios were used as the influent wastewater for the reactor. The MC-ICABFB had relatively good performance on COD and NH4+-N removal and the main residual organic compound in the effluent was phthalates according to the analysis of GC-MC profiles. In addition, a suitable pretreatment process for the FWL to facilitate biological treatment of the wastewater needs further research.
Subject(s)
Bioreactors , Hydraulic Fracking , Waste Disposal, Fluid , Wastewater/chemistry , Acrylic Resins/analysis , Aerobiosis , Aluminum Hydroxide/analysis , Hydrogen-Ion ConcentrationABSTRACT
An aerobic moving bed biofilm reactor (MBBR) was adopted to treat Lurgi coal gasification waste water (LCGW) in about 10 months. The pollutant load and dissolve oxygen (DO) concentration were adjusted by trying to maximize the accumulation of [Formula: see text] in the MBBR for LCGW treatment. The highest [Formula: see text] accumulation proportion [Formula: see text] was 73.9%, but was not stable with influent chemical oxygen demand (COD) and DO concentrations of around 1000 and 1.5â mg/L, respectively. Around 1500â mg/L of influent COD concentration and 1.5â mg/L of DO concentration were proper operation conditions for the aerobic MBBR to achieve relatively stable [Formula: see text] accumulation, with [Formula: see text] ratio at 53% and [Formula: see text] ratio at just 4.3% in the effluent. More specifically, free ammonia concentration and DO concentration affected [Formula: see text] accumulation much more obvious than phenols concentration. The activity and quantity of nitrifying bacteria growth in suspended sludge and biofilm of the MBBR were monitored simultaneously to explain the variations of [Formula: see text] accumulation performance under different operation conditions. An aerobic moving bed biofilm reactor (MBBR) was adopted to treat Lurgi coal gasification waste water (LCGW)in about 10 months. The pollutant load and dissolve oxygen (DO) concentration were adjusted by trying to maximize the accumulation of NO(−)(2)−N in the MBBR for LCGW treatment. The highest NO(−)(2)−N accumulation proportion(NO(−)(2)−Neffluent/TN effluent) was 73.9%, but was not stable with influent chemical oxygen demand (COD) and DO concentrations of around 1000 and 1.5 mg/L, respectively. Around 1500 mg/L of influent COD concentration and 1.5 mg/L of DO concentration were proper operation conditions for the aerobic MBBR to achieve relatively stable NO(−)(2)−N accumulation,with NO(−)(2)−N/TN ratio at 53% and NO(-)(3)−N/TN ratio at just 4.3% in the effluent. More specifically, free ammonia concentration and DO concentration affected NO(2)(−)N accumulation much more obvious than phenols concentration. The activity and quantity of nitrifying bacteria growth in suspended sludge and biofilm of the MBBR were monitored simultaneously toexplain the variations of NO(−)(2)−N accumulation performance under different operation conditions.
Subject(s)
Bacterial Physiological Phenomena , Biofilms , Bioreactors/microbiology , Nitrites/metabolism , Oxygen/analysis , Waste Disposal, Fluid/instrumentation , Wastewater/analysis , Biodegradation, Environmental , Biological Oxygen Demand Analysis , Coal , Gases/chemistryABSTRACT
AIM: To establish a sensitive biotin-avidin enzyme linked immunosorbent assay (BA-ELISA) method for detecting carcinoembryonic antigen (CEA) in serum. METHODS: CEA which had been purified by affinity chromatography was used to immunize the rabbits to produce polyclonal antibodies. Then the antibodies were connected with biotin and horseradish peroxidase (HRP). So BA-ELISA method was established on the basis of 96 microwell plates coated with biotinylated BSA. Finally we examined the sensitivity, specificity, stability and recovery rate of this system and compared the BA-ELISA method with the traditional ELISA, radioimmunoassay and chemiluminescence in detecting CEA concentrations. RESULTS: The stability of this system was proved good. The linear range was from 0.42 to 50 U/mL, the sensitivity was 0.42 U/mL, and the intra-differences together with inter-differences were less than 10.0%. There was significant difference between BA-ELISA and traditional ELISA, while there was no significant difference between BA-ELISA and radioimmunoassay. The regression equation of this method was y=0.04825+0.99674x and r=0.994, and there was no significant difference between the BA-ELISA and chemiluminescence. CONCLUSION: The BA-ELISA method we established to detect CEA was easy to operate, highly sensitive, low in price and suitable for application in clinical detection.
Subject(s)
Carcinoembryonic Antigen/blood , Enzyme-Linked Immunosorbent Assay/methods , Animals , Avidin , Biotin , Breast Neoplasms/blood , Carcinoembryonic Antigen/immunology , Carcinoembryonic Antigen/isolation & purification , Female , Humans , Rabbits , Reference Values , Reproducibility of Results , Sensitivity and SpecificityABSTRACT
AIM: To purify pregnancy associated plasma protein A (PAPP-A) from the pregnancy serum using the methods of G200 gel filtration, reverse affinity chromatography and DEAE ion exchange. METHODS: The male sera were purified by G200 gel filtration and injected into rabbits to obtain rabbit-anti-human antibodies. The antibodies were linked to CNBr-activated G25 gel to make the reverse affinity chromatography. The full-term pregnancy sera were collected and centrifuged, followed by G200 gel filtration, reverse affinity chromatography and DEAE ion exchange. ELISA and SDS-PAGE were performed to detect the activity and the purity of PAPP-A. RESULTS: As detected by the double diffusion, the rabbit-anti-human antibodies were active in the dilution of 1:16, and were further used for purification of PAPP-A. The PAPP-A exited in the last peak with the pH3.0 elutriant by SPA, the first peak by G200 gel filtration, the peak with 0.1 mol/L PBS elutriant by the reverse affinity chromatography, and the peak with 0.45 mol/L NaCl elutriant by the DEAE ion exchange. The SDS-PAGE results indicated that the triple treatments of the pregnancy sera by G200 gel filtration, the reverse affinity chromatography and the DEAE ion exchange effectively enhanced purity of PAPP-A, with a single protein band shown by Western blot, whereas a single purification method produced dirty bands. CONCLUSION: High purity PAPP-A has been obtained, ready for preparation of its monoclonal antibody. The study paves a way for development of PAPP-A based ELISA kits for clinical use.
Subject(s)
Pregnancy-Associated Plasma Protein-A/isolation & purification , Adult , Animals , Female , Humans , Male , Middle Aged , Pregnancy , Pregnancy-Associated Plasma Protein-A/metabolism , Rabbits , Young AdultABSTRACT
A laboratory-scale moving bed biofilm reactor (MBBR) with a volume of 4 L was used to study the biodegradation of coal gasification wastewater. Maximum removal efficiencies of 81%, 89%, 94% and 93% were obtained for COD, phenols, SCN(-) and NH(4)(+)-N, respectively. NO(2)(-)-N accumulation induced increase of effluent COD concentration when the hydraulic residence time (HRT) decreased. Phenols removal was not affected when the HRT decreased from 48 to 32 h. Effluent SCN(-) and NH(4)(+)-N concentration increased with the decrease of the HRT, and decreased gradually when the HRT returned to 48 h. Batch experiments were carried out to study performance of the suspended and attached growth biomass in the MBBR.
Subject(s)
Biofilms , Bioreactors , Coal , Waste Disposal, Fluid/methods , Water Pollutants, Chemical/metabolism , Water Purification/methods , Biodegradation, Environmental , Nitrification , Phenols/metabolism , Quaternary Ammonium Compounds/metabolism , Thiocyanates/metabolismABSTRACT
PLNPK is a pentapeptide compound extracted from pig spleen with a Pro-Leu-Asn-Pro-Lys molecular structure. The spleen is the biggest immune organ in the body, in which there are lots of immunocytes and immune molecules. Our pilot study showed that PLNPK could suppress the transformation and proliferation of T lymphocytes and the production of antibodies in mice. It is widely accepted that most types of glomerulonephritis are immunological diseases caused by the reaction of antigen and antibody. Both humoral immunity and cell-mediated immunity contribute to the progress of these diseases, and suppression of immunoreactions and inflammation is important to ameliorate nephritis. After the immunosuppressive effects of this compound were discovered, this study also examined whether PLNPK had beneficial effects on a rat model of glomerulonephritis. The results suggested PLNPK (200microg/kg/d and 400microg/kg/d) reduced urinary protein excretion, lessened the deposit of autoantibodies along the glomerular basement membrane (GBM), reduced formation of crescent and protein casts, and ameliorated glomerular fibrosis and GBM injury. After treatment with PLNPK (200microg/kg/d and 400microg/kg/d) for 7 days, macrophage infiltration in the glomeruli was markedly reduced. Our results suggest that PLNPK has a beneficial effect on rat anti-GBM nephritis.
Subject(s)
Glomerular Basement Membrane/drug effects , Nephritis/drug therapy , Nephritis/veterinary , Oligopeptides/pharmacology , Oligopeptides/therapeutic use , Peptides/pharmacology , Peptides/therapeutic use , Animals , Autoantibodies/immunology , Cell Proliferation/drug effects , Female , Glomerular Basement Membrane/immunology , Glomerular Basement Membrane/pathology , Glomerular Basement Membrane/ultrastructure , Macrophages/cytology , Macrophages/immunology , Male , Mice , Nephritis/immunology , Nephritis/pathology , Oligopeptides/genetics , Oligopeptides/immunology , Peptides/genetics , Peptides/immunology , Rats , Rats, Wistar , Swine , T-Lymphocytes/drug effects , T-Lymphocytes/immunologyABSTRACT
OBJECTIVE: To investigate the inhibitory effects of tyroservatide and its amino acid mixture on growth of hepatocarcinoma. METHODS: Hepatocarcinoma in nude mice was induced by implantation of cells of human hepatocarcinoma cell line BEL-7402. The inhibition of hepatocarcinoma growth was determined by calculating the tumor volume and measuring the tumor weight. The effects of tyroservatide on tumor cells in nude mice were assessed by immunohistochemical staining of proliferating cell nuclear antigen (PCNA), electron microscopic observation of ultrastructure, and apoptosis of tumor cells using terminal deoxynucleotidyl transferase biotin-dUTP nick end labeling (TUNEL). RESULTS: Tyroservatide significantly inhibited the growth of human hepatocarcinoma in nude mice, with an inhibiting rate more than 60%. But the mixture of amino acid did not show a significant inhibitory effect on the tumor growth. Tyroservatide also induced apoptosis of tumor cells and decreased the expression of PCNA in tumor cells. CONCLUSION: Tyroservatide may significantly inhibit the growth of human hepatocarcinoma in nude mice by inducing apoptosis and inhibiting proliferation of tumor cells.
Subject(s)
Cell Proliferation/drug effects , Liver Neoplasms, Experimental/prevention & control , Liver Neoplasms/prevention & control , Oligopeptides/pharmacology , Xenograft Model Antitumor Assays , Animals , Antineoplastic Agents/pharmacology , Apoptosis/drug effects , Cell Line, Tumor , Humans , Liver Neoplasms/metabolism , Liver Neoplasms/pathology , Liver Neoplasms, Experimental/metabolism , Liver Neoplasms, Experimental/pathology , Mice , Mice, Inbred BALB C , Mice, Nude , Proliferating Cell Nuclear Antigen/metabolism , Tumor BurdenABSTRACT
Tyroserleutide (YSL) is a type of active, low molecular weight polypeptide, comprised of three amino acids, which has antitumor effects. YSL has various advantages over the other bioactive peptides such as its low molecular weight, simple construction, nonimmunogenicity, specificity, few side effects, and ease of synthesis. However, the biological activities contributing to it's antitumor effects are not yet known. We studied the effects of YSL on the in vitro cytotoxic activity of BALB/c mice peritoneal macrophages (PEMphi) against the target tumor cell lines BEL-7402 and B16-F10. We also measured the concentrations of interleukin (IL)-1beta, tumor necrosis factor (TNF)-alpha, and nitric oxide (NO) produced by YSL-activated Mphi, and we determined the concentrations of IL-1beta and NO secreted by YSL-activated murine macrophage RAW264.7 cells. YSL activated Mphi in vitro, inhibited BEL-7402 proliferation, enhanced PEMphi antitumor effects, and stimulated IL-1beta, TNF-alpha, and NO production by RAW264.7 cells. These data suggest that YSL activates the monocyte-macrophage system, which enhances Mphi antitumor effects against BEL-7402 and B16-F10 cells and stimulates the secretion by Mphi of cytotoxic effectors such as IL-1beta, TNF-alpha, and NO.
Subject(s)
Macrophages, Peritoneal/immunology , Macrophages/physiology , Oligopeptides/pharmacology , Animals , Carcinoma/pathology , Female , Humans , Interleukin-1/metabolism , Liver Neoplasms/pathology , Macrophages/drug effects , Macrophages, Peritoneal/drug effects , Mice , Mice, Inbred BALB C , Nitric Oxide/metabolism , Transplantation, Heterologous , Tumor Necrosis Factor-alpha/metabolismABSTRACT
OBJECTIVE: The aim was to investigate the suppression of rat experimental autoimmune uveoretinitis( EAU) by induced immune tolerance via intranasal administration of retinal S antigens. METHODS: The bovine S antigen was purified from bovine retina by salt precipitation and ionic exchange chromatography, the female Lewis rats were used to induce immune tolerance by intranasal administration with purified bovine retinal S antigens and then the rats were used to produce the EAU model by retinal S antigens challenge. The rate of EAU occurrence, the clinical and histological scores, the skin delayed-type hypersensitivity and lymphocyte proliferation stimulated by retinal S antigen and concanavalin A were recorded. The adjunct effect of cyclophosphamide on tolerance induction was observed. RESULTS: After intranasal administration of retinal S antigens, EAU was induced in two of eight ( 25% ) rats in tolerant group, sis of six (100%) rats in control group , the difference of EAU induction rate was significant in tolerant group compared with control (P = 0. 0097) . The average onset time in tolerant group were 16. 5 days, the control group was 10. 3 days, the difference was significant ( F = 26. 32, P = 0. 000; q = 9. 723, P <0. 01). The average clinical scores of EAU in tolerant group were 0. 89, the control group was 3. 94, the difference was significant( F = 12. 48 ,P = 0. 000; q = 7. 904, P < 0. 01 ). The average histological scores of EAU in tolerant group were 1. 21, the control group was 4. 12, the difference was significant( F = 11. 80, P = 0. 000; q = 7. 510,P <0. 01). The histological features in tolerant group were iris blood vessels slightly dilation, few exudates in anterior chamber and vitreous cavity; there were slighter retina swallow and the photoreceptors damages in the tolerant group. The skin delayed-type hypersensitivity and the proliferative responses of lymphocytes stimulated by S antigen and concanavalin A in tolerant group were slighter than that in the control group. Intraperitoneal injection of cyclophosphamide enhanced the effect of immune tolerance slightly. Only intraperitoneal injection of cyclophosphamide did not diminish the severity of the rat EAU. CONCLUSION: The intranasal induced tolerance by retinal S antigens can suppress effectively the prevalence of rat experimental autoimmune uveoretinitis induced by retinal S antigens.