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1.
Differentiation ; : 100801, 2024 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-39048474

RESUMEN

Fibroblast growth factor 7 (FGF7), also known as keratinocyte growth factor (KGF), is an important member of the FGF family that is mainly expressed by cells of mesenchymal origin while affecting specifically epithelial cells. Thus, FGF7 is widely expressed in diverse tissues, especially in urinary system, gastrointestinal tract (GI-tract), respiratory system, skin, and reproductive system. By interacting specifically with FGFR2-IIIb, FGF7 activates several downstream signal pathways, including Ras, PI3K-Akt, and PLCs. Previous studies of FGF7 mutants also have implicated its roles in various biological processes including development of essential organs and tissue homeostasis in adults. Moreover, more publications have reported that FGF7 and/or FGF7/FGFR2-IIIb-associated signaling pathway are involved in the progression of various heritable or acquired human diseases: heritable conditions like autosomal dominant polycystic kidney disease (ADPKD) and non-syndromic cleft lip and palate (NS CLP), where it promotes cyst formation and affects craniofacial development, respectively; acquired non-malignant diseases such as chronic obstructive pulmonary disease (COPD), idiopathic pulmonary fibrosis (IPF), mucositis, osteoarticular disorders, and metabolic diseases, where it influences inflammation, repair, and metabolic control; and tumorigenesis and malignant diseases, including benign prostatic hyperplasia (BPH), prostate cancer, gastric cancer, and ovarian cancer, where it enhances cell proliferation, invasion, and chemotherapy resistance. Targeting FGF7 pathways holds therapeutic potential for managing these conditions, underscoring the need for further research to explore its clinical applications. Having more insights into the function and underlying molecular mechanisms of FGF7 is warranted to facilitate the development of effective treatments in the future. Here, we discuss FGF7 genomic structure, signal pathway, expression pattern during embryonic development and in adult organs and mutants along with phenotypes, as well as associated diseases.

2.
J Inorg Biochem ; 251: 112426, 2024 02.
Artículo en Inglés | MEDLINE | ID: mdl-37980877

RESUMEN

The diiron active site is pivotal in catalyzing transformations in both biological and chemical systems. Recently, a range of biomimetic diiron catalysts have been synthesized, drawing inspiration from the active architecture of soluble methane monooxygenase (sMMO). These catalysts have been successfully deployed for the dehydrogenation of indolines, marking a significant advancement in the field. Using density functional theory (DFT) calculations, we have identified a novel mechanistic pathway that governs the dehydrogenation of indolines catalyzed by a biomimetic diiron complex. Specifically, this reaction is facilitated by the transfer of a hybrid atom from the C1 position of the substrate to the distal oxygen atom of the Fe(III)Fe(III)-1,1-µ-hydroperoxy active species. This transfer serves as the rate-limiting step for the heterolytic cleavage of the OO bond, ultimately generating the substrate cation. The mechanism we propose aligns well with mechanistic investigations incorporating both kinetic isotope effect (KIE) measurements and evaluations of stereochemical selectivity. This research contributes to the broader scientific understanding of catalysis involving biomimetic diiron complexes and offers valuable insights into the catalytic behaviors of non-heme diiron metalloenzymes.


Asunto(s)
Biomimética , Metaloproteínas , Dominio Catalítico , Catálisis , Oxígeno/química
3.
Nat Commun ; 15(1): 4459, 2024 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-38796433

RESUMEN

The magnetic proximity effect can induce a spin dependent exchange shift in the band structure of graphene. This produces a magnetization and a spin polarization of the electron/hole carriers in this material, paving the way for its use as an active component in spintronics devices. The electrostatic control of this spin polarization in graphene has however never been demonstrated so far. We show that interfacing graphene with the van der Waals antiferromagnet CrSBr results in an unconventional manifestation of the quantum Hall effect, which can be attributed to the presence of counterflowing spin-polarized edge channels originating from the spin-dependent exchange shift in graphene. We extract an exchange shift ranging from 27 - 32 meV, and show that it also produces an electrostatically tunable spin polarization of the electron/hole carriers in graphene ranging from - 50% to + 69% in the absence of a magnetic field. This proof of principle provides a starting point for the use of graphene as an electrostatically tunable source of spin current and could allow this system to generate a large magnetoresistance in gate tunable spin valve devices.

4.
ACS Omega ; 8(48): 46034-46042, 2023 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-38075792

RESUMEN

Electronic noses are an artificial olfactory system that mimics the animal olfactory function. Currently, metal oxide semiconductor (MOS) gas sensors play a vital role in the development of high-performance electronic noses and have widespread applications across various fields. They are particularly valuable in ensuring food safety, monitoring air quality, and even detecting explosives for antiterrorism purposes. However, there is an increasing demand for electronic noses to exhibit faster response times in large-scale commercial applications. To address this challenge, we developed a novel MOS gas sensor with a porous ceramic substrate, specifically designed to facilitate rapid gas diffusion. The sensing performance of the sensor array was evaluated and the result showed that the T90 time of porous ceramic-assisted MOS sensor was significantly (57%) shorter than sensors with a normal substrate. Moreover, the electronic nose system had demonstrated remarkable capability in accurately distinguishing between five distinct types of hazardous gases, including VOCs as well as ammonia. Furthermore, a low-cost electronic system was developed and applied to cigarette brand identification; 2490 groups of data were collected for each individual test at only a cost of 20 s. By employing a machine learning algorithm to analyze the data, an accuracy higher than 95% was achieved (96.29% for K nearest neighbor and 96.32% for random forest). We found that our system can resolve the onset time of electronic nose measurement with enough precision, and it was expected that this special approach by using porous ceramic as an insulating substrate can provide a simple and reliable method to manufacture a fast-response electronic nose.

5.
J Hazard Mater ; 442: 130139, 2023 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-36303361

RESUMEN

An important concern during phytoremediation of heavy metal contamination in soils is the risk of leaching of heavy metals before they can be taken up by plants. The most effective method is to use heavy metal stabilizers. However, the stabilization without selectivity will greatly inhibit the phytoremediation effect of all heavy metals. A novel polymer with amino and mercapto groups named as AMP has been prepared as a new exclusive soil stabilizer for Pb. The adsorption of AMP toward Pb belonged to a monolayer adsorption and chemical process. The adsorption capacity of Pb increased with the increase of pH and initial Pb concentration, and obeyed the Langmuir model and pseudo-second-order model, respectively. An amazing maximum adsorption capacity of 588 mg Pb g-1 was reached for AMP when initial concentration was 300 mg Pb L-1, while K2 of 0.594 g mg-1 min-1 was obtained when the initial Pb concentration was 2.0 mg L-1. The distribution coefficient of AMP to Pb in the mixture of five heavy metals was as high as 3110 mL g-1, which was at least 7-fold greater than those of other heavy metals, exhibiting high selective to Pb. AMP showed a fast, large adsorption capacity and good selectivity due to the abundance of sulfhydryl and amino functional groups in the polymer and their interaction with metal ions. The effects of AMP in soil remediation were further tested by a soil column leaching experiment and a pot experiment, and the good stabilization effect of AMP on Pb and the less effect on bioavailability of other heavy metals at recommended doses were verified. This study was expected to solve the problem of leaching risk of the target metal such as Pb in sludge during land use. It provided a new idea of exclusive stabilization to assist phytoremediation of non-target heavy metals by reducing the leaching risk of some special target metal.


Asunto(s)
Metales Pesados , Contaminantes del Suelo , Biodegradación Ambiental , Contaminantes del Suelo/análisis , Plomo , Polímeros , Metales Pesados/análisis , Suelo , Adenosina Monofosfato
6.
Water Res ; 217: 118374, 2022 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-35398806

RESUMEN

Antibiotic resistance genes (ARGs) are considered as emerging environmental contaminants, which should be controlled by wastewater treatment plants to prevent their discharge into the environment. However, conventional treatment techniques generally fail to successfully reduce ARGs, and the release of cell-free ARGs was underestimated. In this study, potassium ferrate (Fe(VI)) pretreatment combined with ultrafiltration (UF) process was developed to remove both cell-associated and cell-free ARGs in real secondary effluent, compared to ferric chloride (Fe(III)) and poly-aluminum chloride (PACl) pretreatment processes. It was found that total ARGs especially cell-free ARGs were effectively removed by Fe(VI) oxidation. However, due to the poor settleability of the negatively charged particles formed by Fe(VI) in the secondary effluent, the removal of cell-associated ARGs was less compared to Fe(III) and PACl pretreatments. The combination of Fe(VI) and UF removed the most ARGs (3.26 - 5.01 logs) due to the efficient removal of cell-free ARGs by Fe(VI) (> 2.15 logs) and co-interception of both cell-associated ARGs and Fe(VI) formed particles of the UF. High-throughput sequencing revealed that Fe(VI) decreased the viability and relative abundances of the potential ARGs hosts. Fe(VI)-UF exhibited the best performance on humic-like fluorescent organic matters removal, as well as the least phytotoxicity in the effluent. Moreover, membrane fouling was remarkably alleviated by Fe(VI) pretreatment because (1) Fe(VI) removed macromolecules such as protein-like and polysaccharide-like substances which would block the membrane pores, (2) Fe(VI) improved the hydrophilicity of foulants and reduced the hydrophobic adsorption between foulants and membrane. In short, Fe(VI)-UF is a promising technology to efficiently remove ARGs (especially cell-free ARGs) and alleviate UF membrane fouling in wastewater reclamation.


Asunto(s)
Ultrafiltración , Purificación del Agua , Antibacterianos/farmacología , Farmacorresistencia Microbiana/genética , Compuestos Férricos , Compuestos de Hierro , Membranas Artificiales , Compuestos de Potasio , Ultrafiltración/métodos , Purificación del Agua/métodos
7.
Chem Commun (Camb) ; 59(1): 118-121, 2022 Dec 22.
Artículo en Inglés | MEDLINE | ID: mdl-36477311

RESUMEN

Transition metal- and photosensitizer-free C(sp3)-H (sulfonyl)amidation reactions have been realized by employing Selectfluor® as a versatile reagent, functioning as a photoactive component, a HAT precursor and an oxidant. Various toluene derivatives, cycloalkanes, natural products and bioactive molecules can be converted into N-containing products under mild conditions in good yield and with high chemo- and site-selectivity.


Asunto(s)
Compuestos de Diazonio , Estructura Molecular , Catálisis
8.
Chemosphere ; 291(Pt 2): 132838, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34762892

RESUMEN

In the presence of dissolved organic matter, the mechanism of algal bioaccumulation of different metals is complex, and its significance goes far beyond the alga-metal binary system. In the presence of 10 and 20 mg L-1 fulvic acid (FA), the maximum tolerance concentrations of Chlorella pyrenoidosa to Ni were 0.25 and 0.26 mmol L-1, and to Zn were 0.62 and 0.68 mmol L-1, respectively. Within the maximum tolerance concentration ranges, the bioaccumulation behaviors of Ni and Zn were systematically compared in the presence of FA. The presence of FA shortened the adsorption equilibrium time and decreased the maximum bioaccumulation capacity of Ni and Zn. The bioaccumulation mechanism of Ni by C. pyrenoidosa was more inclined to monolayer adsorption, while the bioaccumulation mechanism of Zn was more inclined to multilayer adsorption. More details were revealed after the bioaccumulated metals were separated into adsorption and internalization states by 0.01 M EDTA elution. The presence of FA decreased more adsorbed Zn than the adsorbed Ni, due to the different competitive roles of FA in the ternary system of Ni and Zn, but the presence of FA increased the internalized Ni might due to the stronger complexation of Ni-FA. This research indicated that algae had unique bioaccumulation mechanisms for different metals in the presence of FA, which is of great significance to accurately evaluate the ecological risk posed by heavy metals.


Asunto(s)
Chlorella , Metales Pesados , Microalgas , Benzopiranos , Bioacumulación , Materia Orgánica Disuelta , Zinc
9.
J Exp Clin Cancer Res ; 41(1): 257, 2022 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-35996148

RESUMEN

BACKGROUND: G protein-coupled receptor (GPCR) is the most targeted protein family by the FDA-approved drugs. GPCR-kinase 3 (GRK3) is critical for GPCR signaling. Our genomic analysis showed that GRK3 expression correlated with poor prognosis of gastric adenocarcinoma (GAC) patients. However, GRK3's functions and clinical utility in GAC progression and metastases are unknown. METHODS: We studied GRK3 expression in normal, primary, and metastatic GAC tissues. We identified a novel GRK3 inhibitor, LD2, through a chemical-library screen. Through genetic and pharmacologic modulations of GRK3, a series of functional and molecular studies were performed in vitro and in vivo. Impact of GRK3 on YAP1 and its targets was determined. RESULTS: GRK3 was overexpressed in GAC tissues compared to normal and was even higher in peritoneal metastases. Overexpression (OE) of GRK3 was significantly associated with shorter survival. Upregulation of GRK3 in GAC cells increased cell invasion, colony formation, and proportion of ALDH1+ cells, while its downregulation reduced these attributes. Further, LD2 potently and specifically inhibited GRK3, but not GRK2, a very similar kinase to GRK3. LD2 highly suppressed GAC cells' malignant phenotypes in vitro. Mechanistically, GRK3 upregulated YAP1 in GAC tissues and its transcriptional downstream targets: SOX9, Birc5, Cyr61 and CTGF. Knockdown (KD) YAP1 rescued the phenotypes of GRK3 OE in GAC cells. GRK3 OE significantly increased tumor growth but LD2 inhibited tumor growth in the PDX model and dramatically suppressed peritoneal metastases induced by GRK3 OE. CONCLUSIONS: GRK3, a poor prognosticator for survival, conferred aggressive phenotype. Genetic silencing of GRK3 or its inhibitor LD2 blunted GRK3-conferred malignant attributes, suggesting GRK3 as a novel therapeutic target in advanced GAC.


Asunto(s)
Adenocarcinoma , Neoplasias Peritoneales , Neoplasias Gástricas , Adenocarcinoma/tratamiento farmacológico , Adenocarcinoma/genética , Adenocarcinoma/metabolismo , Línea Celular Tumoral , Proliferación Celular/genética , Regulación Neoplásica de la Expresión Génica , Humanos , Neoplasias Peritoneales/genética , Neoplasias Gástricas/tratamiento farmacológico , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismo
10.
Chemosphere ; 274: 129862, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33607597

RESUMEN

Coagulation has been widely applied as a pretreatment for ultrafiltration (UF) membrane in wastewater reclamation, however, it is unable to effectively ensure the removal of organic micropollutants (OMPs) and genotoxicity. To solve this problem, oxidant ferrate (VI) (FeVIO42-, FeVI) was combined with coagulant poly-aluminum chloride (PAC) as the pretreatment of UF to treat secondary effluent, and three oxidant dosing strategies (namely oxidation followed by coagulation (O-FeVI-PAC), simultaneous oxidation and coagulation (S-FeVI-PAC), and coagulation followed by oxidation (C-PAC-FeVI)) were compared at two oxidant doses. The results showed that C-PAC-FeVI pretreatment exhibited the best performance for the removal of DOC (35.9%), UV254 (33.7%), protein (71.8%), and polysaccharide (22.1%). Molecular weight and fluorescence analysis revealed that the removed organics were mainly humic substances. Both the direct UF process and PAC pretreatment showed limited removal of OMPs and genotoxicity, however, the combined pretreatments of FeVI and PAC dramatically removed them. The maximum removal efficiency of the fourteen selected OMPs and genotoxicity was obtained under S-FeVI-PAC (59.6% on average) and C-PAC-FeVI (84.1%), respectively. With respect to membrane fouling control, the normalized flux reduction showed an apparent regularity of C-PAC-FeVI > O-FeVI-PAC > S-FeVI-PAC, however, FeVI dose should be carefully determined. The addition of FeVI delayed the transition of membrane fouling mechanism from pore blockage to cake filtration, especially in C-PAC-FeVI pretreatment, which was confirmed by the fluorescence characterization of hydraulic reversible and hydraulic irreversible foulants. To sum up, C-PAC-FeVI dosing strategy seems to have more potential in membrane fouling alleviation and effluent quality improvement.


Asunto(s)
Ultrafiltración , Purificación del Agua , Cloruro de Aluminio , Compuestos de Hierro , Membranas Artificiales , Oxidantes , Compuestos de Potasio
11.
Environ Pollut ; 288: 117699, 2021 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-34271519

RESUMEN

Sludge landscaping after compost stabilization is a popular recycling process; however, until trace elements (TEs) are extracted by plants and reduced to safe concentrations, they present a potential exposure risk. Three garden plants, Liriope platyphylla Wang et Tang (L. platyphylla), Iris tectorum Maxim (I. tectorum), and Photinia x fraseri Dress (P. x fraseri), were selected for field experiments, and their ability to phytoremediate TEs and the promotion effect of citric acid (CA) were studied over 3 months of observation. Among the three kinds of plants, L. platyphylla had the highest biomass per unit soil area, and the CA treatment further increased the biomass of this plant per unit soil area as well as the uptake of TEs. When treated with 3 mmol kg-1 CA, L. platyphylla showed increases in the bioconcentration factors of Cu, Zn, Pb, and Cd by 24%, 63%, 27%, and 123%, respectively. Because of the large biomass and high concentrations of TEs, L. platyphylla had high phytoremediation indexes for Zn, Cu, Pb, Ni, and Cd, which reached 18.5, 3.7, 3.2, 2.2, and 0.4 mg m-2, respectively, and were further improved by 60%-187% by the CA treatment. These advantages indicate the potential usefulness of L. platyphylla for phytoremediation. The results provide basic data and technical support for the use of sludge-based compost and phytoremediation by garden plants.


Asunto(s)
Compostaje , Metales Pesados , Contaminantes del Suelo , Oligoelementos , Biodegradación Ambiental , Ácido Cítrico , Jardines , Metales Pesados/análisis , Aguas del Alcantarillado , Suelo , Contaminantes del Suelo/análisis
12.
J Biotechnol ; 336: 50-55, 2021 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-34118332

RESUMEN

Improving productivity and decreasing costs for biotherapeutic agents has been a focal driving force in the manufacturing of biologics. Advances in upstream processes have been continuously outpacing the ability for downstream operations to purify biologics, especially monoclonal antibodies. Continuous chromatography has several benefits for biologic purification including automated control, decreased labor, improved productivity, and more consistent product attributes. The goal of this study was to improve productivity and decrease costs associated with batch-mode and continuous purification processes. Productivities using cellulose nanofibers with a protein A ligand offer greater than 30-fold higher productivities than their resin-based equivalents using periodic countercurrent technology with multiple column chromatography. The smaller columns needed for convective mass transfer, faster processing times, and decreased costs allow for a more efficient mAb capture step. Additionally, high throughput purification (grams of mAbs/day) can be achieved from the scale-down model developed using periodic countercurrent technology. These advancements will help drive the evolution of downstream operations to manage the higher workloads due to increased upstream titers in a cost-effective manner.


Asunto(s)
Productos Biológicos , Nanofibras , Anticuerpos Monoclonales , Proteína Estafilocócica A
13.
Sci Total Environ ; 754: 142361, 2021 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-33254848

RESUMEN

The presence of effluent organic matter (EfOM) and organic micro-pollutants (OMPs) in secondary effluent is receiving increasing concern due to their potential impacts on the aquatic environment and human health. In this study, the removal characteristics of EfOM by magnetic ion-exchange resin (MIEX), ozonation, and the hybrid process of MIEX followed by ozonation (M + O) were compared by measuring the bulk organic indicators (BOIs), OMPs, bio-toxicity, and fluorescence. Furthermore, the desorption characteristics of MIEX were comprehensively studied. Ozonation could reduce the OMPs, total fluorescence (TF), genotoxicity, and oestrogenic activity more effectively than MIEX, with reductions of 80.3%, 97.8%, 98.9%, and 94.6%, respectively. The M + O process was capable of removing more EfOM than the individual MIEX or ozonation processes and could reduce the genotoxicity and oestrogenic activity to the detection limit. By implementing MIEX as a pre-treatment, the generation of ammonia-nitrogen and nitrate-nitrogen was effectively reduced in the subsequent ozonation process as MIEX adsorbed organic nitrogen and nitrite-nitrogen. The different regenerants influenced the OMP desorption performance of MIEX by changing the desorption mechanisms, and NaCl + NaOH was the best regenerant due to its high total OMP desorption efficiency. Parallel factor analysis coupled with self-organising maps further explained the differences in fluorescence desorption due to the addition of NaOH to the regenerated solution. Pearson correlation analysis indicated the potential of using spectroscopic indicators, such as ultraviolet absorbance and TF, to assess the evolution of OMPs and bio-toxicity during the M + O and MIEX desorption processes.

14.
Diabetes Res Clin Pract ; 172: 108445, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32949653

RESUMEN

AIMS: Apoptosis and oxidant stress are known to be involved in the pathogenesis of diabetic kidney disease (DKD). We have previously reported that zinc transporter 7 in SLC30 family (SLC30A7) inhibits apoptosis in rat peritoneal mesothelial cells under high glucose (HG) conditions. In the current study, we aimed to investigate whether SLC30A7 had effect for anti-oxidant stress in renal tubular epithelial cells under HG. METHODS: SLC30A7 in HG-induced apoptosis in a normal rat kidney tubular epithelial cell line (NRK-52E cells)/kidneys of STZ-induced diabetic mice was examined and the activity of nuclear factor erythroid 2-related factor 2 (NFE2L2) was further analyzed by using real time RT-PCR, siRNA and Western blot protocols. RESULTS: SLC30A7 was found to be up-regulated, while NFE2L2 was activated in kidneys of STZ-induced diabetic mice and HG-induced apoptosis of NRK-52E cells. Knock-down of SLC30A7 with siRNA protocol resulted in lower intracellular free zinc levels in the cells and decreased zinc distribution in the Golgi apparatus. Furthermore, knock-down of NFE2L2 down-regulated its target HMOX1 gene expression, decreased SLC30A7 activity but increased HG-induced apoptosis. CONCLUSION: The current study provides new evidence that SLC30A7 has anti-oxidant stress effects in HG-induced apoptosis via the NFE2L2/HMOX1 signal transduction pathway.


Asunto(s)
Antioxidantes/metabolismo , Nefropatías Diabéticas/fisiopatología , Glucosa/metabolismo , Hemo Oxigenasa (Desciclizante)/metabolismo , Factor 2 Relacionado con NF-E2/metabolismo , Transducción de Señal/efectos de los fármacos , Animales , Apoptosis , Diabetes Mellitus Experimental/metabolismo , Humanos , Masculino , Ratones , Ratas , Transfección
17.
Front Endocrinol (Lausanne) ; 12: 727915, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34526970

RESUMEN

In obesity and type 2 diabetes, numerous genes are differentially expressed, and microRNAs are involved in transcriptional regulation of target mRNAs, but miRNAs critically involved in the appetite control are not known. Here, we identified upregulation of miR-342-3p and its host gene Evl in brain and adipose tissues in C57BL/6 mice fed with high fat-high sucrose (HFHS) chow by RNA sequencing. Mir342 (-/-) mice fed with HFHS chow were protected from obesity and diabetes. The hypothalamic arcuate nucleus neurons co-express Mir342 and EVL. The percentage of activated NPY+pSTAT3+ neurons were reduced, while POMC+pSTAT3+ neurons increased in Mir342 (-/-) mice, and they demonstrated the reduction of food intake and amelioration of metabolic phenotypes. Snap25 was identified as a major target gene of miR-342-3p and the reduced expression of Snap25 may link to functional impairment hypothalamic neurons and excess of food intake. The inhibition of miR-342-3p may be a potential candidate for miRNA-based therapy.


Asunto(s)
Regulación del Apetito/genética , MicroARNs/genética , Obesidad , Células 3T3-L1 , Animales , Núcleo Arqueado del Hipotálamo/metabolismo , Núcleo Arqueado del Hipotálamo/fisiología , Células Cultivadas , Dieta Alta en Grasa , Regulación de la Expresión Génica , Humanos , Hipotálamo/metabolismo , Hipotálamo/fisiología , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Ratones Obesos , MicroARNs/metabolismo , Neuronas/metabolismo , Neuronas/fisiología , Obesidad/etiología , Obesidad/genética , Obesidad/metabolismo , Regulación hacia Arriba/genética
18.
J Hazard Mater ; 396: 122697, 2020 09 05.
Artículo en Inglés | MEDLINE | ID: mdl-32388183

RESUMEN

Conventional coagulation is widely used as an ultrafiltration membrane pretreatment process in wastewater reclamation, however it shows little ability to reduce organic micro-pollutants (OMPs) and genotoxicity. In this research, powdered activated carbon (PAC) and potassium ferrate were used respectively with polyaluminum chloride (PACl) to enhance coagulation. Filtration experiments of coagulation (CUF), coagulation-adsorption (CAUF) and coagulation-oxidation (COUF) pretreatment combined with densadeg-ultrafiltration processes were conducted under their optimum doses. The effluent water quality of CAUF and COUF could meet the water reuse quality standard for scenic environment use, while total phosphorus in the conventional CUF discharge was higher than the standard. The average removal efficiency of the selected fourteen OMPs was significantly improved by 1.8 times through the CAUF process compared to the CUF process (31.2%), whereas the COUF process (38.4%) showed limited improvement. Prominent reduction of genotoxicity was observed in the CAUF and COUF processes, and the effluent of the CAUF process had the least genotoxicity of 1.0 ±â€¯0.3 µg 4-Nitroquinoline-N-oxide (4-NQO)/L. Moreover, the average transmembrane pressure increasing rate followed the order of CUF (1.5 kPa/d) > COUF (1.1 kPa/d) > CAUF (0.6 kPa/d), indicated that the enhanced coagulation process could relieve membrane fouling effectively.


Asunto(s)
Contaminantes Ambientales , Purificación del Agua , Coagulación Sanguínea , Daño del ADN , Membranas Artificiales , Mutágenos/toxicidad , Ultrafiltración
19.
Chemosphere ; 244: 125449, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31809924

RESUMEN

Wastewater reuse risk and membrane fouling are two concerns in ultrafiltration (UF) of secondary effluent (SE) for wastewater reuse. In this work, several wastewater reuse risk issues, such as dissolved effluent organic matters (dEfOM), organic micro-pollutants (OMPs) and bio-toxicity of SE, as well as membrane fouling were comprehensively investigated when ozonation, UV/H2O2 and UV/persulfate (UV/PS) were used as the pre-treatments for UF process. To be specific, individual UF could remove DOC and UV254 by only 7.5% and 19.8%, respectively, however, humics were largely degraded during the pre-oxidation processes revealed by molecular weight and fluorescence analysis. UF and ozonation showed limited removal of OMPs, however, UV/H2O2 and UV/PS dramatically degraded all the OMPs by more than 80%. Genotoxicity were not detected after the oxidation treatment. Membrane fouling may result from the collaborative effect of organic components, such as humic and protein like substances. Fourier transform infrared spectra of the fouled membranes showed that aromatic CC group and polysaccharides group in dEfOM were largely reduced after the oxidation pre-treatments, resulting in the improved membrane flux sustaining. Increased roughness of the membranes in the combined process supported that the less organics content after the oxidation pre-treatment contributed to improve the performance of the UF process. For the excellent organics degradation in UV/PS pre-treatment process, membrane fouling of subsequent UF process showed maximum mitigation.


Asunto(s)
Membranas Artificiales , Ozono , Purificación del Agua/métodos , Peróxido de Hidrógeno , Peso Molecular , Oxidación-Reducción , Ultrafiltración/métodos , Rayos Ultravioleta , Aguas Residuales , Agua
20.
Chemosphere ; 241: 125090, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31683451

RESUMEN

It is essential to mitigate the risk of exposure to effluent organic matter (EfOM) in aquatic environments to ensure safe wastewater recycling. Magnetic ion-exchange (MIEX) resin adsorption combined with ozonation could provide EfOM removal. However, the poor understanding of the influences of the parameters and mechanisms in the hybrid process has restricted the applications. In this study, the response surface methodology was used to reveal the interactions of the major operation parameters. The degradation behaviour of the EfOM was investigated by using spectroscopy combined with mathematical methods. The effect of the pH on the EfOM removal was also analysed. The maximum efficiency of the removal of dissolved organic carbon (DOC) was 59.77% at the optimal MIEX resin dosage of 7.97 mL/L, ozone concentration of 8 mg/L, agitation speed of 199.84 r/min, and pH of 9.98. The ozonation was superior to resin adsorption in the removal of 1054-Da compounds, while the resin adsorption was advantageous in the removal of 4168-Da compounds. Three fluorescent components (C1, C2, and C3) were more easily subjected to external perturbation than the DOC and ultraviolet absorbance at 254 nm in the oxidation processes. The MIEX resin exhibited low efficiencies of removal of the fluorescent substances. A synchronous fluorescence analysis coupled with a two-dimensional correlation analysis revealed that the variation in EfOM followed the order of fulvic-to humic-like substances in the hybrid process of MIEX and the following ozonation. The pH was the most significant influencing factor in the hybrid process.


Asunto(s)
Resinas de Intercambio Iónico/química , Ozono/química , Eliminación de Residuos Líquidos/métodos , Aguas Residuales/química , Adsorción , Carbono/aislamiento & purificación , Concentración de Iones de Hidrógeno , Fenómenos Magnéticos , Oxidación-Reducción , Eliminación de Residuos Líquidos/instrumentación , Contaminantes Químicos del Agua/química
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