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1.
Chemosphere ; 262: 128215, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33182126

RESUMO

The effluent from conventional treatment process (including anaerobic digestion and anoxic-oxic treatment) for pig farm wastewater was difficult to treat due to its low ratio of biochemical oxygen demand to chemical oxygen demand (BOD5/CODCr) (<0.1). In the present study, electro-Fenton (EF) was used to improve the biodegradability of the mentioned effluent and the properties of self-prepared CeO2-doped multi-wall carbon nanotubes (MWCNTs) electrodes were also studied. An excellent H2O2 production (165 mg L-1) was recorded, after an 80-min electrolysis, when the mass ratio of MWCNTs, CeO2 and pore-forming agent (NH4HCO3) was 6:1:1. Results of scanning electron microscopy (SEM), transmission electron microscope (TEM) and x-ray photoelectron spectroscopy (XPS) showed that addition of NH4HCO3 and the doping of CeO2 could increase the superficial area of the electrode as well as the oxygen reduction reaction (ORR) electro-catalytic performance. The BOD5/CODCr of the wastewater from the first stage AO process increased from 0.08 to 0.45 and CODCr reduced 71.5% after an 80-min electrolysis, with 0.3 mM Fe2+ solution. The non-biodegradable chemical pollutants from the first stage AO process were degraded by EF. The non-biodegradable pollutants identified by LC-MS/MS in the effluent from AO process including aminopyrine, oxadixyl and 3-methyl-2-quinoxalinecarboxylic acid could be degraded by EF process, with the removal rates of 81.86%, 34.39% and 7.13% in 80 min, and oxytetracycline with the removal rate of 100% in 20 min. Therefore, electro-Fenton with the new CeO2-doped MWCNTs cathode electrode will be a promising supplement for advanced treatment of pig farm wastewater.


Assuntos
Cério/química , Eletrólise/métodos , Nanotubos de Carbono/química , Águas Residuárias/química , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Animais , Biodegradação Ambiental , Análise da Demanda Biológica de Oxigênio , Catálise , Eletrodos , Fazendas , Peróxido de Hidrogênio/análise , Oxirredução , Suínos
2.
J Hazard Mater ; 408: 124621, 2021 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-33383458

RESUMO

In this research, bismuth vanadate-doped graphite felt (GF-BiVO4) was successfully prepared by sol-gel method, in which BiVO4 owned superior electro-Fenton (EF) and solar-photo-electro-Fenton (SPEF) performance. Combined with the analysis by X-ray diffractometer (XRD), field emission transmission electron microscopy (FE-TEM), nitrogen adsorption-desorption isotherms and cyclic voltammetry (CV), the changes of electrodes were reflected in structure and physicochemical properties. The doping of monoclinic BiVO4 endued GF with a higher surface area and more electro-active sites and better electrode activity in comparison to Raw-GF. Then, the GFs were used as cathodes to detect •OH concentration with coumarin (COU) as probe molecule and to evaluate photoelectric performance with ciprofloxacin (CIP) in photocatalysis, EF and SPEF processes. The results demonstrated that the concentration of •OH followed an order of SPEF> EF> photocatalysis, which was consistent with the removal rate of CIP (99.8%, 99.4% and 21.2%, respectively) on GF-BiVO4 at 5 min. Further, five degradation pathways of CIP in SPEF system were proposed including the attack on piperazine ring, oxidation on cyclopropyl group, decarboxylation and hydroxyl radical addition, oxidation on benzene group and defluorination. The study provides insights into the enhancement of EF and SPEF performance and the degradation pathway of CIP in SPEF.

3.
J Hazard Mater ; : 124262, 2020 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-33213981

RESUMO

Ciprofloxacin (CIP) is ubiquitous in the environment which poses a certain threat to human and ecology. In this investigation, the physical and electrochemical properties of graphite felt (GF) anodes which affected the anodic oxidation (AO) performance, and the CIP removal effect of GF were evaluated. The GFs were used as anodes for detection of ·OH with coumarin (COU) as molecule probe and removal of CIP in a 150 mL electrolytic cell with Pt cathode (AO-GF/Pt system). The results showed that hydrophilic GF (B-GF) owned higher sp3/sp2 and more oxygen-containing and nitrogen-containing functional groups than the hydrophobic GF (A-GF). Moreover, B-GF possessed higher oxygen evolution potential (1.12 V), more active sites and stronger ·OH generation capacity. Above mentioned caused that B-GF exhibited more superior properties for CIP removal. The best efficiencies (96.95%, 99.83%) were obtained in the AO-B-GF/Pt system at 6.25 mAcm-2 after 10 min (k1, 0.356 min-1) and 60 min (k2, 0.224 min-1), respectively. Furthermore, nine degradation pathways of CIP in AO-B-GF/Pt system were summarized as the cleavage of the piperazine ring, cyclopropyl group, quinolone ring and F atom by ·OH. It provides new insights into the removal and degradation pathways of CIP with GF in AO system.

4.
Chemosphere ; 257: 127205, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32502735

RESUMO

Multi-walled carbon nanotubes (MWCNTs), a common nanomaterial widely used and discharged in environment, might exert toxic effects on aquatic animals. In this paper, filter-feeding tadpole of Xenopus tropicalis was selected as bioindicator to study the exposure effects of MWCNTs suspensions of 0.5, 1, 2, 4 and 8 mg/L for 72 h. The results showed that the tadpoles could remain high survival rate of over 96.7% after 24 h's exposure to MWCNTs, but then decrease considerably, showing a significant time-dependent relationship. The LC50 was 2.53 mg/L for tadpoles exposed to MWCNTs for 72 h, when MWCNTs accumulated in their gills and digestive tracts. Moreover, the enrichment degree of MWCNTs in tadpole was related to exposure density than time. When MWCNTs suspension concentration was not over 1 mg/L, the heart rates increased significantly and then decreased continuously. The survivors from the toxicity test were transferred to fresh filtered water for recovery, but MWCNTs accumulated in the tadpoles' body didn't decrease obviously after 4 days. Although the maximum tadpoles survival rate of 80% was recorded in the exposure group of 0.5 mg/L MWCNTs, only 43.3% of the survivors could recover. Therefore, the final survival rate was negative related to the exposure densities of MWCNTs but positive related to the accumulating degree in tadpoles' body. The results demonstrated that MWCNTs exposure posed potential health risks to filter-feeding organisms by intake and accumulation in organs, which could provide useful information for the reasonable evaluation and scientific management of nanomaterials.


Assuntos
Nanotubos de Carbono/toxicidade , Xenopus/fisiologia , Animais , Brânquias/efeitos dos fármacos , Larva/efeitos dos fármacos
5.
J Environ Manage ; 257: 109968, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31868637

RESUMO

The removal of trace antibiotics from the aquatic environment has received great interest. In this investigation, NaOH activated graphite felt (NaOH-GF) was characterized by multiple-methods, including scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), contact angle, linear sweep voltammetry (LSV) and electron paramagnetic resonance (EPR). The NaOH-GF was then used as the cathode in the electro-Fenton process for oxytetracycline (OTC) degradation, the experiment was carried out in an undivided and light-proof beaker with a Pt anode and a NaOH-GF cathode at pH 3. The results showed that the modification with NaOH enhanced the antibiotics degradation efficiency of graphite felt by increasing the oxygen reduction capacity and hydroxyl radicals yielding rate. Complete OTC removal was achieved at 5.17 mA cm-2 after 40, 60 and 90 s with initial OTC concentration of 22, 44, and 66 µM, respectively. With an initial OTC concentration of 44 µM, after 30 min the removal rates of chemical oxygen demand (COD) by Raw-GF and NaOH-GF were 59.18% and 83.75%, respectively. The proposed degradation mechanism of OTC was an EF process, which consisted of hydroxylation, secondary alcohol oxidation, demethylation, decarbonylation, dehydration and deamination. This study demonstrates that NaOH activated GF cathode possesses high degradation capacity and good stability. It provides insight into the removal of non-biodegradable antibiotics and may shed light on future to its practical application.


Assuntos
Grafite , Oxitetraciclina , Poluentes Químicos da Água , Eletrodos , Peróxido de Hidrogênio , Ferro , Cinética , Oxirredução
6.
J Environ Manage ; 240: 19-26, 2019 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-30928792

RESUMO

The combined process of a long-term biogas digester and double anoxic/oxic tanks is very commonly used in piggery wastewater treatment in South China, but the effluent does not meet the discharge standard of total nitrogen (TN) and chemical oxygen demand (CODCr) due to a low C/N ratio and insufficient organic carbon in digested piggery wastewater. Thus, a typical two-stage anoxic/oxic (A1/O1/A2/O2) process, which is widely used to treat digested piggery wastewater in the engineering application, was selected for study on a laboratory scale. Finally, the average removal efficiency of ammonia nitrogen in the two-stage AO process was 98.7%; at the same time, the content of nitrate increased to 180-190 mg/L. To further eliminate nitrogen, an anaerobic tank (S1), which was equipped the sludge that was acclimated in our laboratory by a high nitrogen loading slurry, was employed to treat the effluent from the two-stage AO process and contributed more than 70% removal efficiency. Further analysis showed that ammonia-oxidizing bacteria (AOB) and nitrite oxidizing bacteria (NOB) in the O1 and O2 tanks together contributed to the conversion of ammonia nitrogen to nitrate, but the process of heterotrophic denitrification was inhibited in the A1 and A2 tanks because of insufficient carbon sources. In addition, most of the nitrate concentration was reduced under conditions with insufficient carbon sources, while Thauera-dominated the bacterial population in the sludge sample of the S1 tank.


Assuntos
Desnitrificação , Águas Residuárias , Reatores Biológicos , China , Nitrogênio , Eliminação de Resíduos Líquidos
7.
Water Res ; 124: 39-48, 2017 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-28738272

RESUMO

Abuse of antibiotics and heavy metals in aquaculture has been widely concerned and might aggravate the spread of resistance genes in environment. To investigate the occurrence and proliferation of antibiotic resistance genes (ARGs) and heavy metal resistance genes (HMRGs), three commonly used antibiotics (tetracycline, sulfanilamide, cefotaxime) and two heavy metals (Zn and Cu) were designed to add individually or jointly in nine fish tanks including five individual exposure tanks of tetracycline (tet), sulfanilamide (sul), cefotaxime (cef), Cu, Zn and four combination exposure tanks of tetracycline + sulfanilamide (tet + sul), tetracycline + sulfanilamide + cefotaxime (tet + sul + cef), tetracycline + sulfanilamide + Cu (tet + sul + Cu), tetracycline + sulfanilamide + Zn (tet + sul + Zn) as well as the control during the experiment period of 180 days. Nineteen ARGs (tetA, tetB, tetC, tetD, tetE, tetG, tetM, tetO, tetQ, tetS, tetW, tetX, tetY, sul1, sul2, sul3, blaDHA, blaMOX, blaFOX), two HMRGs (copA, czcA) and the class 1 integron gene (intI 1) in fish tanks water were investigated. The results showed that the residual rate of antibiotics and heavy metals ranged from 0.03% to 2.46% and 9.25%-52.97%, respectively, positively related to their original concentration and types. Tetracycline resistance genes were more sensitive to antibiotics and easier to be induced and developed than sulfanilamide resistance genes and AmpC ß-lactamase resistance genes. The total relative abundances of ARGs in combined stresses exposure tanks (tet + sul, tet + sul + cef, tet + sul + Cu, tet + sul + Zn) were about 1.01-1.55 times more than the sum of their individual ones. The co-selective effects of cefotaxime on the abundance and diversity of tetracycline resistance genes were stronger than Zn and Cu. Besides, multivariate correlation analysis revealed that tetO, tetQ, tetW and sul3 were in significant correlation with the concentrations of Cu and Zn (r = 0.882-0.992, p < 0.05 or p < 0.01). The significant correlations between tetO and intI1 (p < 0.01), tetW and intI1 (p < 0.05), and sul3 and intI1 (p < 0.05) hinted a potentially serious and undesirable dissemination risk of ribosomal protection proteins gene of ARGs.


Assuntos
Antibacterianos , Metais Pesados , Animais , Aquicultura , Proteínas de Bactérias , Resistência Microbiana a Medicamentos/genética , Peixes , Genes Bacterianos , Medição de Risco , Água , beta-Lactamases
8.
Chin J Integr Med ; 21(8): 601-9, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25533513

RESUMO

OBJECTIVE: To explore susceptibility genes associated with yang-deficiency constitution using single nucleotide polymorphism (SNP) genotyping. METHODS: Based on an epidemiological survey, 30 volunteers with yang-deficiency constitution and 30 volunteers with a balanced constitution were included according to the Classification and Determination Standards of Constitutions in Traditional Chinese Medicine. Peripheral blood was collected and DNA was extracted from white blood cells. A genome-wide association study (GWAS) was conducted by SNP 6.0 genotyping at the Beijing CapitalBio Corporation Ltd. A minimum association P-value (Fisher's exact value) of less than 10(-4) in the allele, genotype, dominant, and recessive models served as the standard for significant association of SNP with yang-deficiency constitution. RESULTS: Among the four genetic models, a total of 42 SNPs were significantly associated with yang-deficiency constitution (Fisher's exact P-values P<10(-4)). These SNPs were adjacent to more than 20 genes, including RGS6, mGluR5, GAPDHL19, and IKZF1. CONCLUSION: Yang-deficiency constitution exhibits the characteristics of polygenic inheritance. This pilot study suggests that the polymorphisms in RGS6, mGluR5, GAPDHL19, and IKZF1 are associated with changes in cyclic adenosine monophosphate and cyclic guanosine monophosphate levels, memory, metabolic energy status, and immune function, respectively in people with yang-deficiency constitution.


Assuntos
Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Deficiência da Energia Yang/genética , Adolescente , Adulto , Estudos de Casos e Controles , Humanos , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Adulto Jovem
9.
Clin Dev Immunol ; 2012: 205313, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22649465

RESUMO

Twenty B candidate epitopes of glycoproteins B (gB2), C (gC2), E (gE2), G (gG2), and I (gI2) of herpes simplex virus type 2 (HSV-2) were predicted using DNAstar, Biosun, and Antheprot methods combined with the polynomial method. Subsequently, the biological functions of the peptides were tested via experiments in vitro. Among the 20 epitope peptides, 17 could react with the antisera to the corresponding parent proteins in the EIA tests. In particular, five peptides, namely, gB2(466-473) (EQDRKPRN), gC2(216-223) (GRTDRPSA), gE2(483-491) (DPPERPDSP), gG2(572-579) (EPPDDDDS), and gI2(286-295) (CRRRYRRPRG) had strong reaction with the antisera. All conjugates of the five peptides with the carrier protein BSA could stimulate mice into producing antibodies. The antisera to these peptides reacted strongly with the corresponding parent glycoproteins during the Western Blot tests, and the peptides reacted strongly with the antibodies against the parent glycoproteins during the EIA tests. The antisera against the five peptides could neutralize HSV-2 infection in vitro, which has not been reported until now. These results suggest that the immunodominant epitopes screened using software algorithms may be used for virus diagnosis and vaccine design against HSV-2.


Assuntos
Herpes Genital/imunologia , Herpesvirus Humano 2/imunologia , Epitopos Imunodominantes/imunologia , Vacinas Virais , Algoritmos , Animais , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Biologia Computacional , Mapeamento de Epitopos , Humanos , Camundongos , Proteínas do Envelope Viral/química , Proteínas do Envelope Viral/imunologia
10.
Zhong Xi Yi Jie He Xue Bao ; 10(5): 508-15, 2012 May.
Artigo em Chinês | MEDLINE | ID: mdl-22587972

RESUMO

OBJECTIVE: To explore the analysis methods for composite traditional Chinese medicine (TCM) constitutions. METHODS: The epidemiological data of TCM constitutions were collected from 974 volunteers via a cross-sectional survey. The samples were classified into 9 constitution types according to the maximal standardized scores of imbalanced constitutions. The correlation matrix of 9 constitutions was computed. The standardized scores of 9 constitutions of all the volunteers were ranked respectively, and the composite status of every two constitutions was observed using cross tabulation. The constitution types of all the volunteers were transformed into ternary code of 9 digits, and the composite status of 3 or more than 3 kinds of constitution types was analyzed. RESULTS: According to the maximal standardized scores of imbalanced constitutions, of 974 volunteers, 227, 148, 218, 102, 31, 81, 44, 97 and 26 volunteers had balanced constitution, qi-deficiency constitution, yang-deficiency constitution, yin-deficiency constitution, phlegm-dampness constitution, heat-dampness constitution, blood stasis constitution, qi-stagnation constitution, and inherited special constitution, respectively. The standardized scores of balanced constitution were negatively correlated with those of imbalanced constitutions, while there was a positive correlation between the standardized scores of every two imbalanced constitutions. Among the 8 imbalanced constitutions, one kind of imbalanced constitutions was usually complicated with another kind of imbalanced constitutions. The number of qi-deficiency constitution complicated with yang-deficiency constitution, qi-deficiency constitution complicated with yin-deficiency constitution, and yin-deficiency constitution complicated with yang-deficiency constitution ranked the top three. The constitution types of 974 volunteers were transformed into a total of 465 ternary codes, showing a total of 465 kinds of constitution types; the simplex constitution, the approximately simplex constitution, and the composite constitution of two or more than two types were found in 259, 130, and 585 volunteers, respectively. CONCLUSION: Cross tabulation can show the composite status of every two constitutions, while the ternary code can show the composite status of three or more than three constitutions.


Assuntos
Constituição Corporal , Medicina Tradicional Chinesa , Adolescente , Adulto , Feminino , Humanos , Masculino , Medicina Tradicional Chinesa/métodos , Pessoa de Meia-Idade , Inquéritos e Questionários , Adulto Jovem
11.
Virol J ; 8: 232, 2011 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-21575169

RESUMO

BACKGROUND: Human herpes simplex virus (HSV) 1 and 2 causes oral, ocular, or genital infections, which remains a significant health problem worldwide. HSV-1 and -2 infections in humans range from localized skin infections of the oral, ocular, and genital regions to severe and often disseminated infections in immunocompromised hosts. Epitope based vaccination is a promising mean to achieve protective immunity and to avoid infections with Human herpes simplex virus type 2 (HSV-2). METHODS: The twelve selected epitopes, six B cell epitopes from different glycoprotein of HSV-2 (amino acid residues 466-473 (EQDRKPRN) from envelope glycoprotein B, 216-223 (GRTDRPSA) from C, 6-18 (DPSLKMADPNRFR) from D, 483-491 (DPPERPDSP) from E, 572-579 (EPPDDDDS) from G and 286-295 (CRRRYRRPRG) from I glycoprotein of HSV-2), four CD4+ T cell epitopes (amino acid residues 21-28 (NLPVLDQL) from D, 162-177 (KDVTVSQVWFGHRYSQ) from B, 205-224 (KAYQQGVTVDSIGMLPRFIP) from D and 245-259 (KPPYTSTLLPPELSD) from D) and two CD8+ T cell epitopes (amino acid residues 10-20 (KMADPNRFRGK) from D and 268-276 (ALLEDPAGT) from D), are responsible for the elicitation of the neutralizing antibodies and cytotoxic T lymphocytes (CTLs) that impart protective immunity to the host. In this study, all above epitopes were inserted into the extracellular fragment (amino acid residues 1-290) of HSV-2 glycoprotein D to construct multi-epitope assembly peptides (MEAPs) by replacing some non-epitope amino acid sequences. The epitope independency of the MEAPs was predicted by three-dimensional software algorithms. The gene of the selected MEAP was expressed in E.coli BL21(DE3), and its protective efficacy against HSV-2 infection was assessed in BALB/c mice. RESULTS: The MEAP, with each inserted epitopes independently displayed on the molecule surface, was selected as candidate proteins. The results showed that the MEAP was highly immunogenic and could elicit high titer neutralizing antibodies and cell-mediated immune responses. CONCLUSIONS: The MEAP provided complete protection against infection with HSV-2 in mice, which indicates that it might be a potential candidate vaccine against HSV-2.


Assuntos
Antígenos Virais/imunologia , Epitopos de Linfócito B/imunologia , Epitopos de Linfócito T/imunologia , Herpes Simples/prevenção & controle , Herpesvirus Humano 2/imunologia , Vacinas contra Herpesvirus/imunologia , Animais , Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , Antígenos Virais/genética , Epitopos de Linfócito B/genética , Epitopos de Linfócito T/genética , Feminino , Herpes Simples/virologia , Vacinas contra Herpesvirus/genética , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Linfócitos T Citotóxicos/imunologia , Vacinas de Subunidades/genética , Vacinas de Subunidades/imunologia , Vacinas Sintéticas/genética , Vacinas Sintéticas/imunologia
12.
Yakugaku Zasshi ; 130(9): 1207-14, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20823678

RESUMO

Human steroid 5alpha-reductase type II (hSRD5A2) and dihydrotestosterone (DHT) play important roles in benign prostatic hyperplasia (BPH). The aim of our study was to establish a novel model to investigate the inhibitory effects of extracts and compounds of Chinese herb medicine on hSRD5A2. The gene, hSRD5A2, was artificially synthesized and cloned into pcDNA3.1(+) vector, which was transfected into CHO cells by liposome. Transfected cells were screened through G418 and MTX. The expressed protein of hSRD5A2 by cells was purified and detected by western blotting. A minimum reactive system comprising hSRD5A2 and testosterone (T) as substrate together with NADPH as hydrogen donor was established for screening inhibitors of hSRD5A2. The reaction system was optimized in the concentrations of T, NADPH, and hSRD5A2 and reaction temperature, time, and activity of hSRD5A2 were determined by the production of DHT. Furthermore, we screened some extracts and compounds of Chinese herb medicine using this model. The concentrations of T, NADPH, and hSRD5A2 were 0.02 microM, 0.8 mM, and 0.05 U/microl, respectively, in the model; maximum activity of hSRD5A2 was achieved at 37 degrees C and 60 min reaction, and mangiferin had significant inhibitory effect on the activity of hSRD5A2. The model in this study is convenient and reliable for screening and evaluation of inhibitors of hSRD5A2; mangiferin may be a potential medicine for the treatment of BPH.


Assuntos
Colestenona 5 alfa-Redutase/metabolismo , Avaliação Pré-Clínica de Medicamentos/métodos , Medicamentos de Ervas Chinesas/farmacologia , Inibidores Enzimáticos/farmacologia , Modelos Biológicos , Animais , Células CHO , Cricetinae , Cricetulus , Medicamentos de Ervas Chinesas/uso terapêutico , Inibidores Enzimáticos/uso terapêutico , Humanos , Técnicas In Vitro , Masculino , Hiperplasia Prostática/tratamento farmacológico , Temperatura , Fatores de Tempo , Xantonas/farmacologia , Xantonas/uso terapêutico
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