RESUMEN
Transarterial chemoembolization (TACE) is commonly used for treating advanced hepatocellular carcinoma (HCC). However, the instability of lipiodol-drug emulsion and the altered tumor microenvironment (TME, such as hypoxia-induced autophagy) postembolization are responsible for the unsatisfactory therapeutic outcomes. Herein, pH-responsive poly(acrylic acid)/calcium phosphate nanoparticles (PAA/CaP NPs) were synthesized and used as the carrier of epirubicin (EPI) to enhance the efficacy of TACE therapy through autophagy inhibition. PAA/CaP NPs have a high loading capacity of EPI and a sensitive drug release behavior under acidic conditions. Moreover, PAA/CaP NPs block autophagy through the dramatic increase of intracellular Ca2+ content, which synergistically enhances the toxicity of EPI. TACE with EPI-loaded PAA/CaP NPs dispersed in lipiodol shows an obvious enhanced therapeutic outcome compared to the treatment with EPI-lipiodol emulsion in an orthotopic rabbit liver cancer model. This study not only develops a new delivery system for TACE but also provides a promising strategy targeting autophagy inhibition to improve the therapeutic effect of TACE for the HCC treatment.
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Carcinoma Hepatocelular , Quimioembolización Terapéutica , Neoplasias Hepáticas , Nanopartículas , Animales , Conejos , Carcinoma Hepatocelular/terapia , Carcinoma Hepatocelular/patología , Neoplasias Hepáticas/terapia , Neoplasias Hepáticas/patología , Aceite Etiodizado/farmacología , Emulsiones , Epirrubicina , Fosfatos de Calcio/farmacología , Microambiente TumoralRESUMEN
Surface-enhanced Raman scattering (SERS) imaging has emerged as a promising tool for guided cancer diagnosis and synergistic therapies, such as combined chemotherapy and photothermal therapy (chemo-PTT). Yet, existing therapeutic agents often suffer from low SERS sensitivity, insufficient photothermal conversion, or/and limited drug loading capacity. Herein, a multifunctional theragnostic nanoplatform consisting of mesoporous silica-coated gold nanostar with a cyclic Arg-Gly-Asp (RGD)-coated gold nanocluster shell (named RGD-pAS@AuNC) is reported that exhibits multiple "hot spots" for pronouncedly enhanced SERS signals and improved near-infrared (NIR)-induced photothermal conversion efficiency (85.5%), with a large capacity for high doxorubicin (DOX) loading efficiency (34.1%, named RGD/DOX-pAS@AuNC) and effective NIR-triggered DOX release. This nanoplatform shows excellent performance in xenograft tumor model of HeLa cell targeting, negligible cytotoxicity, and good stability both in vitro and in vivo. By SERS imaging, the optimal temporal distribution of injected RGD/DOX-pAS@AuNCs at the tumor site is identified for NIR-triggered local chemo-PTT toward the tumor, achieving ultraeffective therapy in tumor cells and tumor-bearing mouse model with 5 min of NIR irradiation (0.5 W cm-2 ). This work offers a promising approach to employing SERS imaging for effective noninvasive tumor treatment by on-site triggered chemo-PTT.
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Nanopartículas , Neoplasias , Humanos , Animales , Ratones , Células HeLa , Oro/farmacología , Terapia Fototérmica , Fototerapia/métodos , Doxorrubicina/farmacología , OligopéptidosRESUMEN
INTRODUCTION: Irritable bowel syndrome (IBS) is a common chronic functional gastrointestinal disorder that presents with abdominal pain/discomfort and altered bowel patterns. IBS has multiple potential causes for which conventional medicines have had limited success, resulting in a significant number of patients who do not sensitively respond to pharmacotherapy for a period of 12 months and who develop a continuing symptom profile (described as refractory IBS) and seek help through (non)pharmacological treatments. The aim of this study is to investigate the efficacy and safety of acupuncture therapy for refractory IBS on the basis of conventional treatments. METHODS AND ANALYSIS: A total of 170 eligible patients who meet the Rome IV criteria for refractory IBS will be randomly allocated to receive acupuncture or sham acupuncture. Each patient will receive 12 sessions of acupuncture over 4 weeks and a 4-week follow-up. The primary outcome will be the IBS Symptom Severity Score. Secondary outcomes will include the proportion of participants experiencing adequate relief of global IBS symptoms, the weekly frequency of defecation, the stool properties assessed by the Bristol Grading Scale, the Work and Social Adjustment Scale, the IBS-Quality of Life score, and the Self-Rating Depression Scale and Self-Rating Anxiety Scale anxiety and depression scores. Outcome measures will be collected at baseline, 2 and 4 weeks of the intervention, and 6 and 8 weeks after the intervention. Categorical variables will be compared with Fisher's exact test or the Wilcoxon rank-sum test, and continuous variables will be compared using Student's t-test or the Wilcoxon rank-sum test. ETHICS AND DISSEMINATION: The entire project has been approved by the ethics committees of Beijing University of Chinese Medicine (2020BZYLL0507) and Sichuan Province Regional Institution for Conducting Research on Traditional Chinese Medicine (2020KL-025). The outcomes of the trial will be disseminated through peer-reviewed publications. TRIAL REGISTRATION NUMBER: NCT04276961.
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Terapia por Acupuntura , Síndrome del Colon Irritable , Dolor Abdominal/etiología , Dolor Abdominal/terapia , Humanos , Síndrome del Colon Irritable/terapia , Calidad de Vida , Ensayos Clínicos Controlados Aleatorios como Asunto , Resultado del TratamientoRESUMEN
BACKGROUND: Functional constipation (FC) is a common gastrointestinal disorder characterized by slow bowel movement and defecation difficulties, significantly impacting patients' quality of life and exerting heavy financial burden to whole society. However, more than 50% FC patients are not completely satisfied with current therapies and alternative therapies are urgently required. Increasing evidences have demonstrated that traditional Chinese medicine has a good therapeutic effect on FC, which is well known for its multitarget and multimode effects on diverse diseases as well as less side effects. Furthermore, studies proved that Qi Di Laxative Decoction was an effective treatment for FC. Its safety and effectiveness should be verified by further studies. METHODS: We will search the following electronic databases for randomized controlled trials to evaluate the clinical efficacy of Qi Di Laxative Decoction in treating FC: Wanfang and Pubmed Database, China National Knowledge Infrastructure Database, Cochrane Central Register of Controlled Trials, Cumulative Index of Nursing and Allied Health Literature, and Excerpta Medica database. Each database will be searched from inception to November 2020. The entire process will include study selection, data extraction, risk of bias assessment, and meta-analyses. RESULTS: This proposed study will evaluate the clinical efficacy of Qi Di Laxative Decoction for patients with FC. The outcomes will include changes in FC relief and adverse effect. CONCLUSION: This proposed systematic review will evaluate the existing evidence on the clinical efficacy of Qi Di Laxative Decoction in treating FC. DISSEMINATION AND ETHICS: The results of this review will be disseminated through peer-reviewed publication. Because all of the data used in this systematic review and meta-analysis has been published, this review does not require ethical approval. Furthermore, all data will be analyzed anonymously during the review process. OSF REGISTRATION NUMBER: DOI 10.17605/OSF.IO/M2ESR.
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Protocolos Clínicos , Estreñimiento/tratamiento farmacológico , Laxativos/normas , Medicina Tradicional China/normas , Humanos , Laxativos/uso terapéutico , Medicina Tradicional China/métodos , Metaanálisis como Asunto , Revisiones Sistemáticas como Asunto , Resultado del TratamientoRESUMEN
Various types of photodynamic agents have been explored for photodynamic therapy (PDT) to destroy cancers located in deep tissues. However, these agents are generally limited by low singlet oxygen (1O2) yields owing to weak absorption in the optical transparent window of biological tissues. Accordingly, in this work, we developed a nanocomposite through the assembly of gold nanobipyramids (GNBPs) on black phosphorus nanosheets (BPNSs). This nanocomposite could simultaneously enhance 1O2 generation and hyperthermia by localized surface plasmon resonance in cancer therapy. As two-dimensional inorganic photosensitizers, BPNSs were hybridized with GNBPs to form BPNS-GNBP hybrid nanosheets. The hybridization markedly increased 1O2 production by the BPNSs through plasmon-enhanced light absorption. The nanocomposite exhibited a higher photothermal conversion efficiency than the BPNSs alone. In vitro and in vivo assays indicated that the BPNS-GNBP hybrid nanocomposite exhibited good tumor inhibition efficacy owing to simultaneous dual-modality phototherapy. In vivo, the nanocomposite suppressed deep-seated tumor growth with minimal adverse effects in mice bearing orthotopic A549 human lung tumors. Taken together, these results demonstrated that our BPNS-GNBP nanocomposite could function as a promising dual-modality phototherapeutic agent for enhanced cancer therapy in future cancer treatments. STATEMENT OF SIGNIFICANCE: In this study, we established a new nanocomposite by assembly of gold nanobipyramids (GNBPs) on black phosphorus nanosheets (BPNSs). Characterization of this nanocomposite showed that BPNS-GNBP enhanced 1O2 generation and hyperthermia. BPNS-GNBP exhibited good tumor inhibition efficacy in vivo and in vitro owing to simultaneous dual-modal phototherapy functions. Moreover, BPNS-GNBP suppressed deep-seated tumor growth in vivo and did not show adverse effects in mice bearing orthotopic A549 human lung tumors. Overall, these results showed that BPNS-GNBP may be used as a promising dual-modal phototherapeutic agent for enhanced cancer therapy in future clinical applications.
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Antineoplásicos/uso terapéutico , Oro/química , Neoplasias Pulmonares/tratamiento farmacológico , Nanocompuestos/química , Fósforo/química , Fármacos Fotosensibilizantes/uso terapéutico , Animales , Antineoplásicos/efectos de la radiación , Antineoplásicos/toxicidad , Línea Celular Tumoral , Oro/efectos de la radiación , Oro/toxicidad , Humanos , Ratones , Nanocompuestos/efectos de la radiación , Nanocompuestos/toxicidad , Fósforo/efectos de la radiación , Fósforo/toxicidad , Fotoquimioterapia , Fármacos Fotosensibilizantes/efectos de la radiación , Fármacos Fotosensibilizantes/toxicidad , Terapia Fototérmica , Oxígeno Singlete/metabolismo , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
In Traditional Chinese Medicine (TCM), Mori ramulus (Chin.Ph.)-the dried twigs of Morus alba L.-is extensively used as an antirheumatic agent and also finds additional use in asthma therapy. As a pathological high xanthine oxidase (XO, EC 1.1.3.22) activity is strongly correlated to hyperuricemy and gout, standard anti-hyperuremic therapy typically involves XO inhibitors like allopurinol, which often cause adverse effects by inhibiting other enzymes involved in purine metabolism. Mori ramulus may therefore be a promissing source for the development of new antirheumatic therapeutics with less side effects. Coumarins, one of the dominant groups of bioactive constituents of M. alba, have been demonstrated to possess anti-inflammatory, antiplatelet aggregation, antitumor, and acetylcholinesterase (AChE) inhibitory activities. The combination of HPLC (DAD) and Q-TOF technique could give excellent separating and good structural characterization abilities which make it suitable to analyze complex multi-herbal extracts in TCM. The aim of this study was to develop a HPLC (DAD)/ESI-Q-TOF-MS/MS method for the identification and profiling of pharmacologically active coumarin glycosides in Mori ramulus refined extracts for used in TCM. This HPLC (DAD)/ESI-Q-TOF-MS/MS method provided a rapid and accurate method for identification of coumarin glycosides-including new natural products described here for the first time-in the crude extract of M. alba L. In the course of this project, two novel natural products moriramulosid A (umbelliferone-6-ß-d-apiofuranosyl-(1â6)-ß-d-glucopyranoside) and moriramulosid B (6-[[6-O-(6-deoxy-α-l-mannopyranosyl)-ß-d-glucopyranosyl]oxy]-2H-1-benzopyran-1-one) were newly discovered and the known natural product Scopolin was identified in M. alba L. for the first time.
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Glicósidos/administración & dosificación , Glicósidos/química , Hiperuricemia/tratamiento farmacológico , Morus/química , Ácido Oxónico/efectos adversos , Ácido Úrico/sangre , Alopurinol/administración & dosificación , Animales , Cromatografía Líquida de Alta Presión , Cumarinas/química , Modelos Animales de Enfermedad , Medicamentos Herbarios Chinos/química , Etanol/química , Glicósidos/farmacología , Hiperuricemia/inducido químicamente , Hiperuricemia/metabolismo , Masculino , Ratones , Estructura Molecular , Extractos Vegetales/química , Distribución Aleatoria , Espectrometría de Masa por Ionización de Electrospray , Espectrometría de Masas en TándemRESUMEN
Highly asymmetric Au nanostructures, such as split Au nanorings and Au nanocups, exhibit attractive plasmonic properties because of their asymmetric geometries. To facilitate their plasmonic applications, effective and facile synthetic methods for producing asymmetric Au nanostructures with controllable sizes and uniform shapes are highly desirable. Herein, we report on an approach for the synthesis of largely asymmetric colloidal Au nanobottles with synthetically tunable overall and opening sizes. Au nanobottles with overall sizes in the range of â¼100-230 nm are obtained through sacrificial templating with differently sized PbS nano-octahedra. The opening sizes of the produced Au nanobottles can be tailored from â¼10 to â¼120 nm by either adjusting the Au/PbS molar ratio in the growth process or controlling the oxidation degree. The achieved size tunability allows the plasmon resonance wavelength of Au nanobottles to be varied in the range of â¼600-900 nm. Our uniform Au nanobottles, which possess controllable sizes, large cavity volumes, and tunable plasmon resonance wavelengths in the visible to near-infrared range, have been further applied for anticancer drug delivery and photothermal therapy. The effects of surface coating and the opening size of Au nanobottles on the drug encapsulation efficiency (EE) and initial burst drug release are systemically evaluated. A high doxorubicin EE and low initial burst drug release are realized with the dense silica-coated Au nanobottles having an opening size of 44 nm. In addition, chemo-photothermal combined therapy has been demonstrated with the doxorubicin-loaded Au nanobottles. Our results will be helpful for the design of Au nanobottles with different sizes and plasmonic properties as well as provide ample opportunities for exploring various plasmon-enabled applications of Au nanobottles.
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Sistemas de Liberación de Medicamentos/métodos , Oro/química , Nanoestructuras/química , Fototerapia/métodos , Antineoplásicos/química , Antineoplásicos/farmacocinética , Antineoplásicos/farmacología , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/efectos de la radiación , Doxorrubicina/química , Doxorrubicina/farmacocinética , Doxorrubicina/farmacología , Humanos , Nanotecnología , Tamaño de la Partícula , Resonancia por Plasmón de SuperficieRESUMEN
Plasmonic nanostructures are of potential in acting as a type of optical agents for cancer photothermal therapy. To effectively function as photothermal therapy agents, plasmonic nanostructures are strongly desired to have good biocompatibility and high photothermal conversion efficiencies. In this study, poly(diallyldimethylammonium chloride)-coated porous Pt nanoparticles are synthesized for photothermal therapy. The Pt nanoparticles possess broadband near-infrared light absorption in the range from 650 to 1200 nm, therefore allowing for selecting different laser wavelengths for photothermal therapy. The as-prepared Pt nanoparticles exhibit remarkable photothermal conversion efficiencies under 809 and 980 nm laser irradiation. In vitro studies indicate that the Pt nanoparticles display good biocompatibility and high cellular uptake efficiencies through an endocytosis pathway. Photothermal heating using 808 nm laser irradiation (>7.0 W cm-2 , 3 min) leads to notable cytotoxic effect, and more than 70% of cells are photothermally ablated after 3 min irradiation at 8.4 W cm-2 . Furthermore, simultaneous application of photothermal therapy synergistically enhances the cytotoxicity of an anti-cancer drug doxorubicin. Therefore, the porous Pt nanoparticles have great potential as an attractive photothermal agent for cancer therapy.
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Antineoplásicos/química , Nanopartículas/química , Compuestos Organoplatinos/química , Materiales Biocompatibles/química , Línea Celular Tumoral , Doxorrubicina/química , Endocitosis/fisiología , Humanos , Rayos Infrarrojos , Nanoestructuras/química , Fototerapia/métodos , Polietilenos/química , Porosidad , Compuestos de Amonio Cuaternario/químicaRESUMEN
Trueperella (T.) pyogenes is an opportunistic pathogen that causes suppurative diseases in domestic animals. In this work, the properties, pathogenesis and phenotypic diversity of T. pyogenes isolates from bovine mastitis were studied. Both pyolysin (plo) and collagen-binding protein (cbp) virulence factor genes were detected by PCR in all T. pyogenes isolates (n = 50). Using the tissue culture plate method, 90% of T. pyogenes isolates were able to form biofilms. The minimum inhibitory concentrations (MICs) of 13 antimicrobials against T. pyogenes isolates were determined. High susceptibility was observed to rifampin (96%), ampicillin (94%), ciprofloxacin (94%), and penicillin (92%), while low susceptibility was found to trimethoprim-sulphamethoxazole (10%) and bacitracin (2%). The intracellular assay revealed that T. pyogenes isolates had different cytopathogenic effects on cells. The high percentage (28.6%) of T. pyogenes isolates suggests that this bacterium is an important contributor to mastitis. Moreover, the high occurrence of multidrug resistance, biofilm production, intracellular survival, and the temporal dynamics of T. pyogenes interactions are key factors for a better understanding of how immunity acts on infections with these bacteria and how they evade immune surveillance, thus highlighting the need for the prudent use of antimicrobial agents in veterinary medicine.
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Infecciones por Actinomycetales/microbiología , Antibacterianos/uso terapéutico , Arcanobacterium/efectos de los fármacos , Farmacorresistencia Bacteriana , Mastitis Bovina/microbiología , Infecciones por Actinomycetales/veterinaria , Animales , Bovinos , China , Recuento de Colonia Microbiana , Femenino , Pruebas de Sensibilidad Microbiana , Factores de VirulenciaRESUMEN
A pilot-scale combined process consisting of an anaerobic baffled reactor (ABR) and an aerobic membrane bioreactor (MBR) for the purpose of achieving easy management, low energy demands, and high efficiencies on nutrient removal from municipal wastewater was investigated. The process operated at room temperature with hydraulic retention time (HRT) of 7.5 h, recycle ratio 1 of 200%, recycle ratio 2 of 100%, and dissolved oxygen (DO) of 1 mg/L and achieved good effluent quality with chemical oxygen demand (COD) of 25 mg/L, NH4 (+)-N of 4 mg/L, total nitrogen (TN) of 11 mg/L, and total phosphorus (TP) of 0.7 mg/L. The MBR achieved partial nitrification, and NO2 (-)-N has been accumulated (4 mg/L). Efficient short-cut denitrification was occurred in the ABR with a TN removal efficiency of 51%, while the role of denitrification and phosphorus removal removed partial TN (14%). Furthermore, nitrogen was further removed (11%) by simultaneous nitrification and denitrification in the MBR. In addition, phosphorus accumulating organisms in the MBR sufficiently uptake phosphorus; thus, effluent TP further reduced with a TP removal efficiency of 84%. Analysis of fluorescence in situ hybridization (FISH) showed that ammonia oxidizing bacteria (AOB) and phosphorus accumulating organisms (PAOs) were enriched in the process. In addition, the accumulation of NO2 (-)-N was contributed to the inhibition on the activities of the NOB rather than its elimination.
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Reactores Biológicos/microbiología , Nitrificación , Fósforo/metabolismo , Aguas Residuales/microbiología , Purificación del Agua/métodosRESUMEN
With the development of Au nanorods for a number of biomedical applications, understanding their cellular responses has become increasingly important. In this study, we systematically evaluated the cellular uptake behaviour and cytotoxicity of Au nanorods with various surface coatings, including organic cetyltrimethylammonium bromide (CTAB), poly(sodium 4-styrenesulfonate) (PSS), and poly(ethylene glycol) (PEG), and inorganic mesoporous silica (mSiO2), dense silica (dSiO2), and titanium dioxide (TiO2). The cellular behaviour of Au nanorods was found to be highly dependent on both the surface coating and the cell type. CTAB-, PSS-, and mSiO2-coated Au nanorods exhibit notable cytotoxicity, while PEG-, dSiO2-, and TiO2-coated Au nanorods do not induce cell injury. Optical imaging studies indicated that the cell type plays a preferential role in Au nanorod cellular uptake. Higher cellular uptake of Au nanorods was seen in U-87 MG, PC-3, MDA-MB-231, and RAW 264.7 cells, as opposed to HepG2 and HT-29 cells. In addition, Au nanorod cellular uptake is also highly affected by serum protein binding to the surface coating. mSiO2-, dSiO2-, and TiO2-coated Au nanorods show significantly higher cellular uptake than PSS- and PEG-coated ones, which results in a better photothermal ablation effect for Au nanorods with the inorganic surface coatings. Our study provides valuable insights into the effects of the surface modification on the biocompatibility, cellular uptake, as well as biomedical functions of Au nanorods.
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Oro/administración & dosificación , Oro/química , Nanotubos/química , Neoplasias Experimentales/química , Neoplasias Experimentales/tratamiento farmacológico , Fotoquimioterapia/métodos , Animales , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/efectos de la radiación , Materiales Biocompatibles Revestidos/administración & dosificación , Materiales Biocompatibles Revestidos/química , Humanos , Hipertermia Inducida/métodos , Nanopartículas del Metal/administración & dosificación , Nanopartículas del Metal/química , Ratones , Neoplasias Experimentales/patología , Fracciones Subcelulares/química , Resultado del TratamientoRESUMEN
Laboratory-scale tests for magnesium ammonium phosphate (MAP) precipitation following urea hydrolysis of human urine were conducted using orthogonal experiment design. The effects of initial pH, temperature and the volumetric ratios of stale urine to fresh urine, on urea hydrolysis in urine were studied to determine the final hydrolysis time to recover most nitrogen from separated human urine by MAP. With a volumetric ratio of stale to fresh urine > 10% and at temperature > or = 20 degrees C, urea hydrolysis could be completed in two days. Alkaline pH inhibited urea hydrolysis progress. The final pH values were all around 9.0 following urine hydrolysis, while the suspension pH might act as an indicator to detect the start and extent of urea hydrolysis. Over 95% of ammonium nitrogen and over 85% of phosphorus from hydrolyzed urine as MAP precipitate were obtained using MgCl2.6H2O and Na2HPO4 x 12H2O as precipitation agents at pH 8.5, molar ratio of Mg2+:NH4(+)-N:PO4(3-)-P at (1.2-1.3):1:1, mixing speed of 120 r/min, and precipitation time and reaction time of 3 h and 15 min, respectively. The precipitate has a structure resembling pure MAP crystal.
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Compuestos de Magnesio/química , Nitrógeno/análisis , Fosfatos/química , Fósforo/análisis , Urea/química , Orina/química , Precipitación Química , Humanos , Concentración de Iones de Hidrógeno , Hidrólisis , Estruvita , Temperatura , Factores de Tiempo , Urea/análisis , Urinálisis/métodosRESUMEN
Non-filamentous sludge bulking occurred during sludge acclimation in lab-scale bio-reactors and the characteristics, properties and degrading pollutants capability of non-filamentous sludge were analyzed. Both low DO concentration (0 - 0.7 mg/L) and low ratio of P/BOD5 (0.78/100) resulted in excessive proliferation of viscous zoogloea and sludge bulking. SVI was directly proportional to extracellular polysaccharides and was inversely proportional to hydrophobicity of sludge. The sludge bulking could be effectively controlled by increasing DO concentration and P/BOD5 ratio. Besides, adding some porous padding into viscous bulking sludge was a useful method which might avoid the deterioration of sludge settlement and maintain good performance in the system. The viscous bulking sludge could not be controlled by addition of NaC1O.
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Oxígeno/metabolismo , Fósforo/metabolismo , Aguas del Alcantarillado/química , Eliminación de Residuos Líquidos/métodos , Biodegradación Ambiental , Oxígeno/química , Aguas del Alcantarillado/microbiología , Eliminación de Residuos Líquidos/instrumentación , Zoogloea/metabolismoRESUMEN
Efficiency of pollution degradation, performance of activated sludge, effect of temperature fluctuation and recalcitrant organic compounds on system stability were investigated in OSA process for minimization of excess sludge. CAS process and OSA process were run with synthetic wastewater for 240 d. The results indicate that the OSA process excels the CAS process as a whole. COD removal efficiency in OSA process was slightly more than that in CAS. Removal efficiency of nitrogen and phosphorus could be enhanced to 42.58% and 53.84% respectively. Biological phosphorus accumulation in aerobic sludge from OSA and CAS were 2.69 g and 1.11 g per 100 g dry sludge, which further approved biological phosphorus removal in OSA process. Because of alternative aerobic and anaerobic environment in OSA process, sludge settleability and activity are improved. SVI in OSA process was 97 averagely. SOUR and dehydrogenase activity of sludge in OSA were higher appreciably than those in CAS. Protein concentration was higher above 1.69 mg x g(-1) and polysaccharide concentration was lower 6.7 mg x g(-1) in OSA sludge than those in CAS, which confirms the effect of anaerobic tank on sludge performance and microorganism diversity. Lower polysaccharide concentration in OSA sludge improves the settleability. Contrasting to CAS process, OSA process is more sensitive to impact of p-nitrophenol(PNP) and more inactive to temperature fluctuation. Temperature fluctuation led to an increase of the concentration of COD, NH4(+) -N, SS in effluent while sludge production Y(MLSS/COD) was reduced to 0.403 mg x mg(-1) and 0.227 mg x mg(-1) in CAS and OSA. When concentration of PNP was increased abruptly to 10 mg x L(-1), biological nutrient removal was ceased in OSA process. Once OSA system is impacted, it is difficult to restore.
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Bacterias Anaerobias/metabolismo , Nitrógeno/metabolismo , Fósforo/metabolismo , Aguas del Alcantarillado/microbiología , Eliminación de Residuos Líquidos/métodos , Biodegradación Ambiental , Carbono/química , Carbono/aislamiento & purificación , Carbono/metabolismo , Nitrógeno/química , Nitrógeno/aislamiento & purificación , Nitrofenoles/química , Nitrofenoles/aislamiento & purificación , Nitrofenoles/metabolismo , Compuestos Orgánicos/química , Compuestos Orgánicos/aislamiento & purificación , Compuestos Orgánicos/metabolismo , Fósforo/química , Fósforo/aislamiento & purificación , TemperaturaRESUMEN
To realize the simultaneous removal and recovery of phosphate and partial nitrogen from stale human urine, a series of lab-scale jar tests, adopting MgCl2 x 6H2O as precipitant, were conducted to study the influence of the molar ratio of Mg/PO4(3-)-P, pH, mixing speed, reaction time and precipitation time on MAP precipitation. The experiment results showed that the molar ratio of Mg/PO4(3-)-P was found to be a very important operating parameter to affect phosphorus recovery efficiency. When the molar ratio of Mg/PO4(3-)-P was above 1.3:1, the phosphorus recovery efficiency was above 95% and the residual phosphorous was less than 10 mg/L in the solution. Increasing pH with 10 mol/L NaOH solution could not increase the recovery phosphorus efficiency obviously. Without pH control, the optimal parameters of reaction time, precipitation time and mixing speed could be set at 20 min, 2.0 h and 120 r/min, respectively. To reveal the chemical characteristics of MAP products from human urine, three MAP product samples, with no pH adjustment and under the above optimal operation condition, were obtained at different Mg/PO4(3-)-P molar ratios of 1:1, 1.3:1 and 1.5:1, respectively, and analyzed with SEM, XRD and ICP instrumentation. These precipitates were identified as nearly pure struvite (12.62% of P, 5.71% of N and 9.91% of Mg) with the presence of trace calcium, potassium and sodium. The contents of phosphorus, nitrogen and magnesium in the precipitates were 13.54%, 5.34% and 9.01% (Mg/PO4(3-)-P = 1:1), 13.78%, 5.23% and 9.36% (Mg/PO4(3-)-P = 1.3:1), as well as 13.34%, 5.12% and 9.15% (Mg/PO4(3-)-P = 1.5:1), respectively.