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1.
Environ Res ; 246: 118564, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38417658

RESUMEN

Metal-organic frameworks (MOFs) have shown great prospects in wastewater remediation. However, the easy aggregation, difficult separation and inferior reusability greatly limit their large-scale application. Herein, we proposed a facile, green and low-cost strategy to construct robust and stable MOF-based hydrogel beads (Fe-BTC-HBs) in a gram scale, and employed them to remove antibiotics from wastewater. As a result, the Fe-BTC-HBs demonstrated outstanding adsorption capacity for both ofloxacin (OFL) and tetracycline (TC) (281.17 mg/g for OFL and 223.60 mg/g for TC) under a near-neutral environment. The main adsorption mechanisms of OFL and TC were hydrogen bonding and π-π stacking interaction. Owing to its macroscopic granule and stable structure, Fe-BTC-HBs can be separated rapidly from wastewater after capturing antibiotics, and more than 85% adsorption capacity still remained after six cycles, while the powdered Fe-BTC only showed less than 6% recovery efficiency with massive weight loss (around 92%). In real industrial effluent, the adsorption performance of Fe-BTC-HBs toward two antibiotics exhibited negligible decreases (2.9% for OFL and 2.2% for TC) compared with that in corresponding solutions. Furthermore, Fe-BTC-HBs also had appealing economic and environmental benefit. Overall, the macro-manufactured MOF beads have the promising potential for the large-scale wastewater treatment.


Asunto(s)
Estructuras Metalorgánicas , Contaminantes Químicos del Agua , Antibacterianos/química , Aguas Residuales , Contaminantes Químicos del Agua/química , Tetraciclina , Adsorción , Cinética
2.
Water Environ Res ; 95(12): e10969, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38148739

RESUMEN

In this work, a composite flocculant (polyferric titanium sulfate-polydimethyldiallylammonium chloride [PFTS-PDMDAAC]) with a rich spatial network structure was prepared for the treatment of simulated wastewater containing polystyrene (PS) micro-nanoparticles. Characterization results showed that the surface of the PFTS-PDMDAAC was a three-dimensional network polymer of chain molecules that exhibited good thermal stability and formed an amorphous polymer containing multiply hydroxyl-bridged titanium and iron. When n(OH- ) : n(Fe) = 1:2, n(PO4 3- ) : n(Fe) = 0.35, n(Ti) : n(Fe) = 1:8, n(DMDAAC) : n(Fe) = 5:100, and the polymerization temperature is 60°C, the prepared composite flocculant has the best effect. The effects of dosage, pH, and agitation intensity on the flocculation properties of PFTS-PDMDAAC were also studied. The optimal removal rates of PS-µm and haze by PFTS-PDMDAAC were 85.60% and 90.10%, respectively, at a stirring intensity of 200 rpm, a pH of 9.0, and a PFTS-PDMDAAC dosage of 20 mg/L. The flocs produced by the PFTS-PDMDAAC flocculation were large and compact in structure, and the flocculation mechanism was mainly based on adsorption bridging. Kaolin played a promoting role in the process of PS-µm removal by PFTS-PDMDAAC floc and accelerated the formation of large and dense flocs. This study provided a reference for the coagulation method to remove micro-nanopollutants in the actual water treatment process. PRACTITIONER POINTS: A composite flocculant with rich spatial network structure (PFTS-PDMDAAC) was prepared. PFTS-PDMDAAC can effectively remove micro-nano polystyrene (PS) in wastewater. The floc produced by PFTS-PDMDAAC is large and compact in structure. The flocculation mechanism of PFTS-PDMDAAC is mainly adsorption bridging.


Asunto(s)
Aguas Residuales , Purificación del Agua , Microplásticos , Plásticos , Titanio/química , Floculación , Purificación del Agua/métodos
3.
Environ Int ; 115: 70-78, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29550711

RESUMEN

Hospital wastewater is one of the possible sources responsible for antibiotic resistant bacteria spread into the environment. This study proposed a promising strategy, electro-peroxone (E-peroxone) pretreatment followed by a sequencing batch reactor (SBR) for simulated hospital wastewater treatment, aiming to enhance the wastewater treatment performance and to reduce antibiotic resistance genes production simultaneously. The highest chemical oxygen demand (COD) and total organic carbon (TOC) removal efficiency of 94.3% and 92.8% were obtained using the E-peroxone-SBR process. The microbial community analysis through high-throughput sequencing showed that E-peroxone pretreatment could guarantee microbial richness and diversity in SBR, as well as reduce the microbial inhibitions caused by antibiotic and raise the amount of nitrification and denitrification genera. Specially, quantitative real-time PCRs revealed that E-peroxone pretreatment could largely reduce the numbers and contents of antibiotic resistance genes (ARGs) production in the following biological treatment unit. It was indicated that E-peroxone-SBR process may provide an effective way for hospital wastewater treatment and possible ARGs reduction.


Asunto(s)
Bacterias , Farmacorresistencia Bacteriana , Técnicas Electroquímicas/métodos , Hospitales , Aguas Residuales/microbiología , Purificación del Agua/métodos , Antibacterianos/farmacología , Bacterias/efectos de los fármacos , Bacterias/aislamiento & purificación , Reactores Biológicos , Peróxido de Hidrógeno , Oxidación-Reducción
4.
Nat Commun ; 8(1): 566, 2017 09 18.
Artículo en Inglés | MEDLINE | ID: mdl-28924149

RESUMEN

The intercalation compounds with various electrochemically active or inactive elements in the layered structure have been the subject of increasing interest due to their high capacities, good reversibility, simple structures, and ease of synthesis. However, their reversible intercalation/deintercalation redox chemistries in previous compounds involve a single cationic redox reaction or a cumulative cationic and anionic redox reaction. Here we report an anionic redox chemistry and structural stabilization of layered sodium chromium sulfide. It was discovered that the sulfur in sodium chromium sulfide is electrochemically active, undergoing oxidation/reduction rather than chromium. Significantly, sodium ions can successfully move out and into without changing its lattice parameter c, which is explained in terms of the occurrence of chromium/sodium vacancy antisite during desodiation and sodiation processes. Our present work not only enriches the electrochemistry of layered intercalation compounds, but also extends the scope of investigation on high-capacity electrodes.The rational design of intercalation electrodes is largely confined to the optimization of redox chemistry of transition metals and oxygen. Here, the authors report the single anionic redox process in NaCrS2 where it is sulfur rather than chromium that works as the electrochemical active species.

5.
ACS Appl Mater Interfaces ; 8(38): 25229-42, 2016 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-27588896

RESUMEN

The improved ionic conductivity (1.64 × 10(-4) S cm(-1) at room temperature) and excellent electrochemical stability of nanoporous ß-Li3PS4 make it one of the promising candidates for rechargeable all-solid-state lithium-ion battery electrolytes. Here, elastic properties, defect thermodynamics, phase diagram, and Li(+) migration mechanism of Li3PS4 (both γ and ß phases) are examined via the first-principles calculations. Results indicate that both γ- and ß-Li3PS4 phases are ductile while γ-Li3PS4 is harder under volume change and shear stress than ß-Li3PS4. The electrochemical window of Li3PS4 ranges from 0.6 to 3.7 V, and thus the experimentally excellent stability (>5 V) is proposed due to the passivation phenomenon. The dominant diffusion carrier type in Li3PS4 is identified over its electrochemical window. In γ-Li3PS4 the direct-hopping of Lii(+) along the [001] is energetically more favorable than other diffusion processes, whereas in ß-Li3PS4 the knock-off diffusion of Lii(+) along the [010] has the lowest migration barrier. The ionic conductivity is evaluated from the concentration and the mobility calculations using the Nernst-Einstein relationship and compared with the available experimental results. According to our calculated results, the Li(+) prefers to transport along the [010] direction. It is suggested that the enhanced ionic conductivity in nanostructured ß-Li3PS4 is due to the larger possibility of contiguous (010) planes provided by larger nanoporous ß-Li3PS4 particles. By a series of motivated and closely linked calculations, we try to provide a portable method, by which researchers could gain insights into the physicochemical properties of solid electrolyte.

6.
Mol Pharm ; 12(8): 3020-31, 2015 Aug 03.
Artículo en Inglés | MEDLINE | ID: mdl-26086430

RESUMEN

A redox-sensitive prodrug, octreotide(Phe)-polyethene glycol-disulfide bond-paclitaxel [OCT(Phe)-PEG-ss-PTX], was successfully developed for targeted intracellular delivery of PTX. The formulation emphasizes long-circulation-time polymer-drug conjugates, combined targeting based on EPR and OCT-receptor mediated endocytosis, sharp redox response, and programmed drug release. The nontargeted redox-sensitive prodrug, mPEG-ss-PTX, and the targeted insensitive prodrug, OCT(Phe)-PEG-PTX, were also synthesized as controls. These polymer-PTX conjugates, structurally confirmed by 1H NMR, exhibited approximately 23,000-fold increase in water solubility over parent PTX and possessed drug contents ranging from 11% to 14%. The redox-sensitivity of the objective OCT(Phe)-PEG-ss-PTX prodrug was verified by in vitro PTX release profile in simulated reducing conditions, and the SSTRs-mediated endocytosis was demonstrated by flow cytometry and confocal laser scanning microscopy analyses. Consequently, compared with mPEG-PTX and OCT(Phe)-PEG-PTX, the OCT(Phe)-PEG-ss-PTX exhibited much stronger cyotoxicity and apoptosis-inducing ability against NCI-H446 tumor cells (SSTRs overexpression), whereas a comparable cytotoxicity of these prodrugs was obtained against WI-38 normal cells (no SSTRs expression). Finally, the in vivo studies on NCI-H466 tumor-bearing nude mice demonstrated that the OCT(Phe)-PEG-ss-PTX possessed superior tumor-targeting ability and antitumor activity over mPEG-PTX, OCT(Phe)-PEG-PTX and Taxol, as well as minimal collateral damage. This targeted redox-sensitive polymer-PTX prodrug system is promising in tumor therapy.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Sistemas de Liberación de Medicamentos , Octreótido/química , Paclitaxel/farmacología , Polietilenglicoles/química , Profármacos/química , Carcinoma Pulmonar de Células Pequeñas/tratamiento farmacológico , Animales , Antineoplásicos Fitogénicos/administración & dosificación , Antineoplásicos Fitogénicos/química , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Portadores de Fármacos/química , Humanos , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patología , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Micelas , Oxidación-Reducción , Paclitaxel/administración & dosificación , Paclitaxel/química , Polímeros/química , Carcinoma Pulmonar de Células Pequeñas/metabolismo , Carcinoma Pulmonar de Células Pequeñas/patología , Células Tumorales Cultivadas , Ensayos Antitumor por Modelo de Xenoinjerto
7.
J Pharm Sci ; 104(6): 2018-2028, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25820241

RESUMEN

In this study, a novel PTX prodrug, octreotide(Phe)-polyethene glycol-paclitaxel [OCT(Phe)-PEG-PTX], was successfully synthesized and used for targeted cancer therapy. A nontargeting conjugate, mPEG-PTX, was also synthesized and used as a control. Chemical structures of OCT(Phe)-PEG-PTX and mPEG-PTX were confirmed using (1) H nuclear magnetic resonance and circular dichroism. The drug contents in both the conjugates were 12.0% and 14.0%, respectively. Compared with the parent drug (PTX), OCT(Phe)-PEG-PTX, and mPEG-PTX prodrugs showed a 20,000- and 30,000-fold increase in water solubility, respectively. PTX release from mPEG-PTX and OCT(Phe)-PEG-PTX exhibited a pH-dependent profile. Moreover, compared with mPEG-PTX, OCT(Phe)-PEG-PTX exhibited significantly stronger cytotoxicity against NCI-H446 cells (SSTR overexpression) but comparable cytotoxicity against WI-38 cells (no SSTR expression). Results of confocal laser scanning microscopy revealed that the targeting prodrug labeled with fluorescence probe was selectively taken into tumor cells via SSTR-mediated endocytosis. In vivo investigation of prodrugs in nude mice bearing NCI-H446 cancer xenografts confirmed that OCT(Phe)-PEG-PTX prodrug exhibited stronger antitumor efficacy and lower systemic toxicity than mPEG-PTX and commercial Taxol. These results suggested that OCT(Phe)-PEG-PTX is a promising anticancer drug delivery system for targeted cancer therapy.


Asunto(s)
Antineoplásicos/administración & dosificación , Sistemas de Liberación de Medicamentos , Neoplasias/tratamiento farmacológico , Octreótido/administración & dosificación , Paclitaxel/administración & dosificación , Profármacos/administración & dosificación , Receptores de Somatostatina/metabolismo , Animales , Antineoplásicos/química , Antineoplásicos/farmacocinética , Antineoplásicos/uso terapéutico , Línea Celular Tumoral , Portadores de Fármacos/química , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Micelas , Neoplasias/metabolismo , Neoplasias/patología , Octreótido/química , Octreótido/uso terapéutico , Paclitaxel/química , Paclitaxel/farmacocinética , Paclitaxel/uso terapéutico , Polietilenglicoles/química , Profármacos/química , Profármacos/farmacocinética , Profármacos/uso terapéutico
8.
Mol Cell Biol ; 35(5): 778-88, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25512613

RESUMEN

Interleukin-1ß (IL-1ß) is a key proinflammatory cytokine that initiates several signaling cascades, including those involving CCAAT/enhancer binding proteins (C/EBPs). The mechanism by which IL-1ß propagates a signal that activates C/EBP has remained elusive. Nemo-like kinase (NLK) is a mitogen-activated protein kinase (MAPK)-like kinase associated with many pathways and phenotypes that are not yet well understood. Using a luciferase reporter screen, we found that IL-1ß-induced C/EBP activation was positively regulated by NLK. Overexpression of NLK activated C/EBP and potentiated IL-1ß-triggered C/EBP activation, whereas knockdown or knockout of NLK had the opposite effect. NLK interacted with activating transcription factor 5 (ATF5) and inhibited the proteasome-dependent degradation of ATF5 in a kinase-independent manner. Consistently, NLK deficiency resulted in decreased levels of ATF5. NLK cooperated with ATF5 to activate C/EBP, whereas NLK could not activate C/EBP upon knockdown of ATF5. Moreover, TAK1, a downstream effector of IL-1ß that acts upstream of NLK, mimicked the ability of NLK to stabilize ATF5 and activate C/EBP. Thus, our findings reveal the TAK1-NLK pathway as a novel regulator of basal or IL-1ß-triggered C/EBP activation though stabilization of ATF5.


Asunto(s)
Factores de Transcripción Activadores/metabolismo , Proteínas Potenciadoras de Unión a CCAAT/metabolismo , Regulación Enzimológica de la Expresión Génica , Interleucina-1beta/fisiología , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Quinasas Quinasa Quinasa PAM/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismo , Transducción de Señal , Animales , Secuencia de Bases , Línea Celular Tumoral , Células HEK293 , Humanos , Luciferasas/metabolismo , Ratones , Ratones Noqueados , Microscopía Confocal , Datos de Secuencia Molecular , Fosforilación , Plásmidos/metabolismo , Interferencia de ARN , Transfección
9.
Bioresour Technol ; 173: 96-103, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25285765

RESUMEN

Two parallel sequence batch reactors (SBRs) were operated, with and without TCS addition, to research the causes of sludge reduction by uncouplers. Three possible mechanisms of sludge reduction by TCS were studied: (1) occurrence of metabolic uncoupling, (2) consumption of more energy to resist the infection of TCS, (3) promotion of lysis-cryptic growth by TCS addition. Results showed the remarkable reduction of electronic transport system (ETS) activity and specific cellular ATP (SATP) in TCS reactor, which proved the occurrence of metabolic uncoupling. The increasing amounts of extracellular polymeric substances (EPS), as measured by chemical methods and excitation-emission matrix (EEM) fluorescence spectra, implied microorganisms consumed more energy to resist TCS. The similar DNA concentrations of the effluents in two reactors indicated sludge lysis was not intensified by TCS. Therefore, uncoupler might not only cause metabolic uncoupling but also induce more energy consumption in the production of some substances to resist uncoupler.


Asunto(s)
Bacterias Anaerobias/metabolismo , Técnicas de Cultivo Celular por Lotes/instrumentación , Reactores Biológicos/microbiología , Salicilanilidas/metabolismo , Aguas del Alcantarillado/microbiología , Desacopladores/metabolismo , Purificación del Agua/instrumentación , Contaminación de Equipos/prevención & control , Diseño de Equipo , Análisis de Falla de Equipo
10.
Tumour Biol ; 35(3): 2075-80, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24092575

RESUMEN

Upregulation of sphingosine kinase 1 (SPHK1) protein has been reported to be associated with a poor prognosis in a variety of malignant tumors. However, the role of SPHK1 in bladder cancer (BC) has not been thoroughly elucidated. The purpose of this study was to assess SPHK1 expression and to explore its contribution to BC. Real-time quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR) was conducted to detect SPHK1 mRNA expression in 37 pairs of fresh-frozen BC tissues and corresponding noncancerous tissues. Results showed that SPHK1 mRNA expression level in BC tissues was significantly higher than that in corresponding noncancerous tissues. To investigate the association between SPHK1 protein expression and clinicopathological characteristics of BC, immunohistochemistry (IHC) was performed in 153 archived paraffin-embedded BC samples. Interestingly, high SPHK1 expression was significantly associated with histologic grade (P = 0.045) and tumor stage (P < 0.001) of patients with BC. The Kaplan-Meier survival curve showed that patients with high SPHK1 expression had significantly reduced overall 5-year survival rates (P < 0.001). Multivariate Cox regression analysis further suggested that the increased expression of SPHK1 was an independent poor prognostic factor for this disease. In conclusion, our data offer the convincing evidence for the first time that the increased expression of SPHK1 may be involved in the pathogenesis and progression of BC. SPHK1 might be a potential marker to predict the prognosis in BC.


Asunto(s)
Biomarcadores de Tumor/análisis , Fosfotransferasas (Aceptor de Grupo Alcohol)/biosíntesis , Neoplasias de la Vejiga Urinaria/enzimología , Neoplasias de la Vejiga Urinaria/mortalidad , Anciano , Femenino , Humanos , Inmunohistoquímica , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Fosfotransferasas (Aceptor de Grupo Alcohol)/análisis , Pronóstico , Modelos de Riesgos Proporcionales , Reacción en Cadena en Tiempo Real de la Polimerasa , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Neoplasias de la Vejiga Urinaria/patología
11.
Zhong Yao Cai ; 36(11): 1721-6, 2013 Nov.
Artículo en Chino | MEDLINE | ID: mdl-24956807

RESUMEN

OBJECTIVE: To study the effects of nitrogen (N), phosphorus (P2O5) and potassium (K2O) fertilizers on the growth, yield total saponins content and nutrient absorption of Pulsatilla cernua and provide a theoretical basis for good agriculture practice. METHODS: Field plot experiments was conducted, based on the D-saturation optimal design with three factors of nitrogen, phosphorus and potassium. Samples collected periodically were used for determination the contents of nutrient and total saponins, and for measurement of yield and agronomic characters. RESULTS: Nutrient contents in Pulsatilla cernua varied with growth stage and part under the same growth stage. Nutrient contents in aerial part were higher than that in root, while the proportion of nutritional absorption from seedling stage to the middle growth stage was larger than that at the late growth stage. Yield and total saponins content of Pulsatilla cernua were significantly influenced by the N1P2O5 and K2O applications, among three factors, N had the greatest effects, the next was K2O and P5O2. CONCLUSION: Pulsatilla cerntua under field cultivation should be fertilized properly, top-dressing with these fertilizers during the early growth stage and increasing the proportion of potassium. According to total saponin production of Pulsatilla cernua, the optimum fertilization model for high yield and good quality is 180 kg/hm2 of N, 79.74 kg/hm2 of P2O5, and 225 kg/hm2 of K20, with a N : P2O : K2O ratio of approximately 2.3 : 1 : 2.8.


Asunto(s)
Nitrógeno/metabolismo , Fósforo/metabolismo , Potasio/metabolismo , Pulsatilla/crecimiento & desarrollo , Saponinas/análisis , Agricultura/métodos , Biomasa , Fertilizantes , Nitrógeno/química , Fósforo/química , Raíces de Plantas/química , Raíces de Plantas/crecimiento & desarrollo , Raíces de Plantas/metabolismo , Potasio/química , Pulsatilla/química , Pulsatilla/metabolismo , Control de Calidad , Estaciones del Año , Semillas/crecimiento & desarrollo , Semillas/metabolismo
12.
Brain Imaging Behav ; 5(3): 181-8, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21637990

RESUMEN

This study further investigates the influence of temporarily disrupting the blood-brain barrier (BBB) on the level of manganese used in AIM fMRI other than the recognized function of allowing that substance to enter into the activated brain regions more effectively during the BBB opening. We injected manganese into Wistar rats through ICA following the disruption of BBB with mannitol in a functional MRI test of the visual cortex. Through comparing MRI signal intensity and manganese contents in the visual cortex of rats received visual stimuli of unequal degree after the restoration of BBB, we found that the signal in the visual cortex could be further enhanced on T1WI given visual stimulation after the restoration of BBB. Temporary BBB disruption has an additional advantage in allowing Mn(2+) to enter the CSF or brain for later transference to the activated brain area. So the dosage of manganese in AIM fMRI could be minimized by extending the stimulus.


Asunto(s)
Barrera Hematoencefálica/fisiología , Imagen por Resonancia Magnética/métodos , Manganeso/fisiología , Animales , Interpretación Estadística de Datos , Diuréticos/farmacología , Aumento de la Imagen , Procesamiento de Imagen Asistido por Computador , Masculino , Manganeso/líquido cefalorraquídeo , Manganeso/metabolismo , Manitol/farmacología , Estimulación Luminosa , Ratas , Ratas Wistar , Corteza Visual/fisiología , Campos Visuales
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