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1.
Environ Sci Technol ; 55(23): 16130-16142, 2021 12 07.
Artículo en Inglés | MEDLINE | ID: mdl-34813327

RESUMEN

Dissolved silica is a major concern for a variety of industrial processes owing to its tendency to form complex scales that severely deteriorate system performance. In this work, we present a pretreatment technology using a Joule-heated sponge to rapidly remove silica from saline waters through adsorption, thereby effectively mitigating silica scaling in subsequent membrane desalination processes. The adsorbent sponge is fabricated by functionalizing two-dimensional layered double hydroxide (LDH) nanosheets on a porous, conductive stainless-steel sponge. With the application of an external voltage of 4 V, the Joule-heated sponge achieves 85% silica removal and 95% sponge regeneration within 15 min, which is much more efficient than its counterpart without Joule-heating (360 min for silica adsorption and 90 min for sponge regeneration). Material characterization and reaction kinetics analysis reveal that electrostatic interactions and "memory effect"-induced intercalation are the primary mechanisms for silica removal by the LDH nanosheets. Moreover, Joule-heating reduces the boundary layer resistance on nanosheets and facilitates intraparticle diffusion of dissolved silica, thereby increasing silica removal kinetics. Joule-heating also enhances the release of silicate ions during the regeneration stage through exchange with the surrounding anions (OH- or CO32-), resulting in a more efficient sponge regeneration. Pretreatment of silica-rich feedwaters by the Joule-heated sponge effectively reduces reverse osmosis membrane scaling by amorphous silica scale, demonstrating great potential for silica scaling control in a broad range of engineered processes.


Asunto(s)
Dióxido de Silicio , Contaminantes Químicos del Agua , Adsorción , Hidróxidos , Cinética , Contaminantes Químicos del Agua/análisis
2.
Environ Sci Technol ; 53(22): 13302-13311, 2019 Nov 19.
Artículo en Inglés | MEDLINE | ID: mdl-31621307

RESUMEN

Composite magnetic aluminum hydroxide at iron oxide nanomaterials, Al(OH)3@Fe3O4, with a well-defined core-shell structure, were used as pretreatment adsorbents for the removal of silica in brackish water. The Al(OH)3 outer shell confers silica adsorption capacity, and the superparamagnetic Fe3O4 core allows material separation and magnetic recovery. The as-prepared nanomaterials (2 g L-1) remove ∼95 and ∼80% silica from Si-rich solutions with 0.5 and 2 mM initial silica concentrations, respectively. Regeneration under basic conditions was evaluated, and post-adsorption treatment with 0.05 M NaOH yielded optimal material reusability. After four regeneration cycles, the Al(OH)3@Fe3O4 nanomaterials retain their magnetic property while still being able to remove ∼40% silica from solutions at an adsorbent concentration of 2 g L-1. The mechanism of silica adsorption onto the surface of the nanomaterials was probed using several spectroscopic techniques. ATR-FTIR (attenuated total reflection-Fourier transform infrared) integrated with two-dimensional correlation analysis shows that silica species vary from Q2 to Q4 with adsorption time corresponding to silica polymerization. 29Si solid-state NMR spectra show an upfield chemical shift displacement of the Q2 signal, which indicates the formation of Q4 units, suggesting silica polymerization onto the Al(OH)3 shell. In addition, a laboratory-scale reverse osmosis setup was used to evaluate Al(OH)3@Fe3O4 as pretreatment materials for silica removal. Results show that silica scaling was significantly alleviated, and water recovery was enhanced when feed waters were pretreated with the magnetic nanomaterials. Taken together, our study highlights the promise of magnetic Al(OH)3@Fe3O4 nanomaterials in treating brackish water and achieving higher water recovery for inland desalination.


Asunto(s)
Dióxido de Silicio , Contaminantes Químicos del Agua , Adsorción , Aluminio , Hierro , Ósmosis
3.
J Transl Med ; 16(1): 93, 2018 04 11.
Artículo en Inglés | MEDLINE | ID: mdl-29642919

RESUMEN

BACKGROUND: ALK rearrangement-advanced NSCLC patients respond to crizotinib. ALK rearrangement is currently determined with RT-PCR. VENTANA IHC is a standard method to identify ALK protein overexpression in NSCLC; however, VENTANA IHC has rarely been used to determine the response to crizotinib in Chinese patients with NSCLC and ALK overexpression. To better clarify the clinical implication of VENTANA IHC to detect ALK rearrangements, we conducted this study to analyze VENTANA IHC and RT-PCR in a large cohort of Chinese patients with NSCLC undergoing screening for ALK rearrangements. METHODS: A total of 1720 patients with NSCLC who had ALK rearrangements detected by VENTANA IHC and/or RT-PCR were included in this analysis. We compared the efficacy and survival of ALK-positive patients detected by VENTANA IHC and RT-PCR. We used NGS to identify patients in whom the two methods were inconsistent. RESULTS: Among 1720 patients, 187 (10.87%) were shown to be ALK-positive by VENTANA IHC and/or RT-PCR, and 66 received crizotinib treatment. We identified 10.27% (172/1674) of patients as ALK-positive by the VENTANA IHC method, and 12.73% (41/322) of patients had ALK rearrangements by the RT-PCR method. Twenty-nine of 276 (10.51%) ALK-positive patients were simultaneously analyzed using VENTANA IHC and RT-PCR. The overall response rates were 65.90% (29/44) by VENTANA IHC and 55.88% (19/34) by RT-PCR. The disease control rates were 86.36% (38/44) by VENTANA IHC and 76.47% (26/34) by RT-PCR. In contrast, the median progression-free survival for VENTANA IHC and RT-PCR was 8.5 and 9.2 months, respectively. The VENTANA IHC and RT-PCR results obtained for 6 of 17 ALK-positive patients were inconsistent based on NGS; specifically, 4 patients had EML4-ALK fusions, 2 patients had non EML4-ALK fusions, 1 patient had a KCL1-ALK fusion, and one patient had a FBXO36-ALK fusion. CONCLUSIONS: VENTANA IHC is a reliable and rapid screening tool used in routine pathologic laboratories for the identification of suitable candidates for ALK-targeted therapy. VENTANA IHC has moderate sensitivity and a slightly higher association with response to therapy with ALK inhibitors, and some VENTANA IHC-positive, but RT-PCR-negative cases may benefit from crizotinib.


Asunto(s)
Quinasa de Linfoma Anaplásico/genética , Pueblo Asiatico , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/enzimología , Crizotinib/uso terapéutico , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/enzimología , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/métodos , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Pulmón de Células no Pequeñas/patología , Crizotinib/farmacología , Femenino , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Inmunohistoquímica , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patología , Masculino , Persona de Mediana Edad , Supervivencia sin Progresión , Adulto Joven
4.
Environ Sci Technol ; 51(24): 14092-14099, 2017 Dec 19.
Artículo en Inglés | MEDLINE | ID: mdl-29149558

RESUMEN

Dissolved organic matter (DOM) is ubiquitous in aqueous environments and plays a significant role in pollutant mitigation, transformation and organic geochemical circulation. DOM is also capable of forming carcinogenic byproducts in the disinfection treatment processes of drinking water. Thus, efficient methods for DOM quantification are highly desired. In this work, a novel sensor for rapid and selective detection of humic substances (HS), a key component of DOM, based on fluorescence quenching of nitrogen-doped carbon quantum dots was developed. The experimental results show that the HS detection range could be broadened to 100 mg/L with a detection limit of 0.2 mg/L. Moreover, the detection was effective within a wide pH range of 3.0 to 12.0, and the interferences of ions on the HS measurement were negligible. A good detection result for real surface water samples further validated the feasibility of the developed detection method. Furthermore, a nonradiation electron transfer mechanism for quenching the nitrogen-doped carbon-dots fluorescence by HS was elucidated. In addition, we prepared a test paper and proved its effectiveness. This work provides a new efficient method for the HS quantification than the frequently used modified Lowry method in terms of sensitivity and detection range.


Asunto(s)
Sustancias Húmicas , Nitrógeno , Carbono , Puntos Cuánticos , Agua
5.
Water Res ; 246: 120681, 2023 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-37801982

RESUMEN

The synergistic effect of protein-silica complexation leads to exacerbated membrane fouling in the membrane desalination process, exceeding the individual impacts of silica scaling or protein fouling. However, the molecular-level dynamics of silica binding to proteins and the resulting structural changes in both proteins and silica remain poorly understood. This study investigates the complexation process between silica and proteins-negatively charged bovine serum albumin (BSA) and positively charged lysozyme (LYZ) at neutral pH-using infrared spectroscopy (IR), in situ attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR), and multiple computational simulations. The findings reveal that both protein and silica structures undergo changes during the complexation process, with calcium ions in the solution significantly exacerbating these alterations. In particular, in situ ATR-FTIR combined with two-dimensional correlation spectroscopy analysis shows that BSA experiences more pronounced unfolding, providing additional binding sites for silica adsorption compared to LYZ. The adsorbed proteins promote silica polymerization from lower-polymerized to higher-polymerized species. Furthermore, molecular dynamics simulations demonstrate greater conformational variation in BSA through root-mean-square-deviation analysis and the bridging role of calcium ions via mean square displacement analysis. Molecular docking and density functional theory calculations identify the binding sites and energy of silica on proteins. In summary, this research offers a comprehensive understanding of the protein-silica complexation process, contributing to the knowledge of synergistic behaviors of inorganic scaling and organic fouling on membrane surfaces. The integrated approach used here may also be applicable for exploring other complex complexation processes in various environments.


Asunto(s)
Calcio , Dióxido de Silicio , Simulación del Acoplamiento Molecular , Albúmina Sérica Bovina/química , Espectroscopía Infrarroja por Transformada de Fourier , Iones , Adsorción
6.
Chin J Cancer ; 31(10): 463-70, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22980418

RESUMEN

With the development and improvement of new sequencing technology, next-generation sequencing (NGS) has been applied increasingly in cancer genomics research over the past decade. More recently, NGS has been adopted in clinical oncology to advance personalized treatment of cancer. NGS is used to identify novel and rare cancer mutations, detect familial cancer mutation carriers, and provide molecular rationale for appropriate targeted therapy. Compared to traditional sequencing, NGS holds many advantages, such as the ability to fully sequence all types of mutations for a large number of genes (hundreds to thousands) in a single test at a relatively low cost. However, significant challenges, particularly with respect to the requirement for simpler assays, more flexible throughput, shorter turnaround time, and most importantly, easier data analysis and interpretation, will have to be overcome to translate NGS to the bedside of cancer patients. Overall, continuous dedication to apply NGS in clinical oncology practice will enable us to be one step closer to personalized medicine.


Asunto(s)
Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Mutación , Neoplasias/genética , Medicina de Precisión , Secuenciación de Nucleótidos de Alto Rendimiento/economía , Humanos , Análisis de Secuencia de ADN
7.
Water Res ; 220: 118702, 2022 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-35665674

RESUMEN

Pre-ozonation coupled with ceramic membrane filtration has been widely used to alleviate membrane fouling. However, information on the efficiency and underlying mechanism of pre-ozonation in the evolution of ceramic membrane biofouling is limited. Herein, filtration experiments with a synthesis wastewater containing activated sludge were conducted in a cross-flow system to evaluate the effects of pre-ozonation on ceramic membrane biofouling. Results of flux tests show that pre-ozonation aggravated biofouling at the early stage, but alleviated the biofouling at the late stage. In situ FTIR spectra show that the aggravated biofouling with pre-ozonation was mainly caused by the enhanced complexation between phosphate group from DNA and Al2O3 surface and the increased rigid of proteins' structure. At the early stage, more severe pore blockage further substantiated the higher permeate resistance. By contrast, more dead cells were observed on membrane surface at the late stage, indicating the prevention of biofouling development after long-term pre-ozonation. Additionally, the structures and compositions of cake layers at the early and late stages exhibited considerable differences accompanied by the variation in microbial community with the evolution of biofouling. Therefore, this work demonstrates the effectiveness of pre-ozonation in biofouling in long-term operation and provides mechanistic insights into the evolution of biofouling on ceramic membrane.


Asunto(s)
Incrustaciones Biológicas , Ozono , Purificación del Agua , Cerámica , Filtración/métodos , Membranas Artificiales , Ozono/química , Purificación del Agua/métodos
8.
Oncol Lett ; 21(1): 68, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33365079

RESUMEN

Esophageal squamous cell carcinoma (ESCC) is a highly malignant and deadly tumor. Radiation therapy is one of the primary treatments for locally advanced ESCC. However, the biomarkers for prognosis of definitive radiation remain undefined. Peripheral blood circulating tumor (ct)DNA provides information of tumor genetic alterations and has been confirmed as a potential non-invasive biomarker for several types of cancer. The present study investigated the clinical implications of ctDNA detection in patients with ESCC and receiving definitive radiation therapy. Patients with locally advanced ESCC were retrospectively recruited. Plasma samples were collected before, during and following radiation therapy. Next-generation sequencing was performed to identify somatic mutations in 180 genes. A total of 69 baseline and post-radiation plasma samples were collected from 25 patients. A total of 59 non-silent single nucleotide variants were present in 33 genes. All pre-radiation and 58.3% (14/24) of post-radiation samples had at least one mutation. Patients with lymph node metastases (LNM) exhibited a higher number of pre-radiation mutations compared with those without LNM. The variables, progression-free survival (PFS) and overall survival (OS) of the patients with one baseline mutation were not significantly different compared with that in patients with more than one baseline mutation. Patients with initial ctDNA-positive post-radiation samples exhibited significantly reduced PFS (P=0.047) and OS (P=0.005) compared with that in patients with ctDNA-negative samples. The post-radiation plasma ctDNA status was an independent prognostic factor from univariate and multivariate analyses. Dynamic monitoring of ctDNA during follow-up was examined. The results indicated that ctDNA was a predictive and prognostic marker in patients with ESCC and receiving definitive radiation therapy, which may guide subsequent treatment.

9.
Water Res ; 185: 116203, 2020 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-32731075

RESUMEN

Organic fouling and inorganic scaling are the main hurdles for efficient operation of reverse osmosis (RO) technology in a wide range of applications. This study demonstrates dual-functionality surface modification of thin-film composite (TFC) RO membranes to simultaneously impart anti-scaling and anti-fouling properties. Two different grafting approaches were adapted to functionalize the membrane surface with sulfonic groups: (i) non-specific grafting of vinyl sulfonic acid (VSA) via redox radical initiation polymerization and (ii) covalent bonding of hydroxylamide-O-sulfonic acid (HOSA) to the native carboxylic groups of the polyamide layer via carbodiimide mediated reaction. Both approaches to graft sulfonic groups were effective in increasing surface wettability and negative charge density of the TFC-RO membranes without significant alteration of water and salt permeabilities. Importantly, we verified through surface elemental analysis that covalently bound HOSA effectively covers the native carboxylic groups of the PA layer. Both the VSA and HOSA membranes exhibited lower flux decline during silica scaling and organic (alginate) fouling relative to the control unmodified membrane, demonstrating the unique versatility of sulfonic groups to endow the TFC-RO membranes with dual functionality to resist scaling and fouling. In particular, the HOSA membrane showed excellent physical cleaning efficiencies with water flux recoveries of 92.5 ± 1.0% and 88.4 ± 6.4% for silica scaling and alginate fouling, respectively. Additional results from silica nucleation experiments and atomic force measurements provided insights into the mechanisms of improved resistance to silica scaling and organic fouling imparted by the surface-functionalized sulfonic groups. Our study highlights the promise of controlled functionalization of sulfonic groups on the polyamide layer of TFC membranes to enhance the applications of RO technology in treatment and reuse of waters with high scaling and fouling potential.


Asunto(s)
Dióxido de Silicio , Purificación del Agua , Filtración , Membranas Artificiales , Ósmosis
10.
Sci Total Environ ; 719: 137513, 2020 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-32120111

RESUMEN

Anaerobic ammonium oxidation (anammox) bacteria are sensitive and susceptible to operating condition fluctuations that can lead to the instability of a bioreactor. Through multivariate spectral analysis, the dynamic changes of intracellular and extracellular metabolites of anammox sludge under the declined temperature stress were characterized. It was found that effluent fluorescence components were positively related to the bacterial activity, and the response of the protein-like substances to the temperature change was more sensitive than that of humic substances. Under the transient disturbance during temperature change from 35 to 15 °C, anammox system tended to considerably excrete extracellular polymeric substances to resist the low temperature inhibition. However, the long-term exposure of the sludge at 10 °C resulted in the considerably inhibition of sludge activity, granular disintegration and heterotrophic denitrification bacteria increase. The two-dimensional correlation analysis further revealed that the humic acid in extracellular polymeric substances was preferentially responded to the temperature change than protein. Anammox bacteria tended to increase the intracellular protein and electron transfer-related reactive substance excretion to counteract the low temperature inhibition. Herein, both the intra- and extra-cellular response characteristics of anammox sludge to temperature variation were successfully resolved via the combined spectra. This work provides a comprehensive understanding on the mechanism of anammox sludge to temperature variation and may be valuable for the development of bioreactor monitoring techniques.


Asunto(s)
Reactores Biológicos , Compuestos de Amonio , Anaerobiosis , Nitrógeno , Oxidación-Reducción , Aguas del Alcantarillado , Temperatura
11.
EBioMedicine ; 60: 102990, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32927274

RESUMEN

BACKGROUND: Although TP53 co-mutation with KRAS/ATM/EGFR/STK11 have been proved to have predictive value for response to immune checkpoint inhibitors (ICIs), not all TP53 mutations are equal in this context. As the main part of TP53 mutant types, Missense and Nonsense alternations in TP53 as independent factors to predict the response to ICIs within Lung Adenocarcinoma (LUAD) patients have not yet been reported. METHODS: An integrated analysis based on multiple-dimensional data types including genomic, transcriptomic, proteomic and clinical data from published lung adenocarcinoma data and local database of LUAD taking immune checkpoint inhibitors. Gene set enrichment analysis (GSEA) was used to determine potentially relevant gene expression signatures between specific subgroups. Single-sample GSEA (GSVA) is conducted to calculate the score for enrichment of a set of genes regulating DNA damage repair (DDR) pathway. FINDINGS: The TP53-missense-mutation group showed increased PD-L1 (CD274) level and enriched IFN-γ signatures compared with the TP53-wild-type subgroup, but no differences were noted in patients with nonsense-mutant vs wild-type p53. Furthermore, a group of suppressor Immune cells like M2 Macrophage and Neutrophils are found enriched in nonsense group. On the other-side, both TP53 missense and nonsense mutations are associated with elevated TMB and neoantigen levels and contribute equally to DNA damage repair deficiency. The distribution regarding to multi-dimensional factors determining the efficacy of ICIs finally transformed into diverse clinical benefits for LUAD. TP53 missense but not -nonsense Mutants are associated with better clinical benefits taking antiPD-1/1L. However, all such TP53 subgroups responds well to nivolumab (antiPD-L1) plus ipilimumab (antiCTLA-4) therapy. INTERPRETATION: Our study demonstrated that not all TP53 mutations are equal in predicting efficacy in patients with LUAD treated with ICIs. Multi-center data showed that TP53 missense and nonsense mutations were significantly different in terms of associations with PD-L1 expression, IFN-γ signatures and TME composition. Special attention should be paid to potential TP53 mutation heterogeneity when evaluating TP53 status as biomarker for ICIs. FUNDING: The study was supported by Key Lab System Project of Guangdong Science and Technology Department - Guangdong Provincial Key Lab of Translational Medicine in Lung Cancer (Grant No. 2017B030314120, to Yi-Long WU).


Asunto(s)
Adenocarcinoma del Pulmón/tratamiento farmacológico , Adenocarcinoma del Pulmón/genética , Adenocarcinoma del Pulmón/mortalidad , Biomarcadores de Tumor , Mutación , Proteína p53 Supresora de Tumor/genética , Adenocarcinoma del Pulmón/metabolismo , Antígeno B7-H1/antagonistas & inhibidores , Codón sin Sentido , Biología Computacional/métodos , Daño del ADN , Reparación del ADN , Perfilación de la Expresión Génica , Humanos , Inhibidores de Puntos de Control Inmunológico/farmacología , Inhibidores de Puntos de Control Inmunológico/uso terapéutico , Quinasas Janus , Estimación de Kaplan-Meier , Terapia Molecular Dirigida , Mutación Missense , Pronóstico , Factores de Transcripción STAT , Transducción de Señal/efectos de los fármacos , Resultado del Tratamiento , Proteína p53 Supresora de Tumor/metabolismo
12.
Thorac Cancer ; 11(8): 2279-2290, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32633046

RESUMEN

BACKGROUND: Patient-derived organoid (PDO) models are highly valuable and have potentially widespread clinical applications. However, limited information is available regarding organoid models of non-small cell lung cancer (NSCLC). This study aimed to characterize the consistency between primary tumors in NSCLC and PDOs and to explore the applications of PDOs as preclinical models to understand and predict treatment response during lung cancer. METHODS: Fresh tumor samples were harvested for organoid culture. Primary tumor samples and PDOs were analyzed via whole-exome sequencing. Paired samples were subjected to immunohistochemical analysis. There were 26 antineoplastic drugs tested in the PDOs. Cell viability was assessed using the Cell Titer Glo assay 7-10 days after drug treatment. A heatmap of log-transformed values of the half-maximal inhibitory concentrations was generated on the basis of drug responses of PDOs through nonlinear regression (curve fit). A total of 12 patients (stages I-III) were enrolled, and 7 paired surgical tumors and PDOs were analyzed. RESULTS: PDOs retained the histological and genetic characteristics of the primary tumors. The concordance between tumors and PDOs in mutations in the top 20 NSCLC-related genes was >80% in five patients. Sample purity was significantly and positively associated with variant allele frequency (Pearson r = 0.82, P = 0.0005) and chromosome stability. The in vitro response to drug screening with PDOs revealed high correlation with the mutation profiles in the primary tumors. CONCLUSIONS: PDOs are highly credible models for detecting NSCLC and for prospective prediction of the treatment response for personalized precision medicine. KEY POINTS: Lung cancer organoid models could save precious time of drug testing on patients, and accurately select anticancer drugs according to the drug sensitivity results, so as to provide a powerful supplement and verification for the gene sequencing.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/genética , Evaluación Preclínica de Medicamentos/métodos , Genómica/métodos , Neoplasias Pulmonares/genética , Organoides/patología , Anciano , Carcinoma de Pulmón de Células no Pequeñas/patología , Femenino , Humanos , Neoplasias Pulmonares/patología , Masculino , Persona de Mediana Edad
13.
Environ Int ; 131: 105045, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31352263

RESUMEN

In this work, a thin-film composite forward osmosis (FO) membrane was fabricated on polyethersulfone substrate by interfacial polymerization with naturally-available humic acid (HA) as a stable membrane additive in the support layer. Compared with the pristine polyethersulfone substrate, the incorporation of HA significantly altered the cross-section structure, increased average pore size and porosity of the substrate, leading to a thinner polyamide layer, further increasing the water flux (permeability). Specifically, the FO membrane showed a higher water flux (~20 L m-2 h-1) with the introduction of HA than the membrane synthesized without HA (~15 L m-2 h-1) in the FO mode with 2 M NaCl as draw solution. Moreover, the selectivity of the membrane was improved ~45% by dosing 0.8 wt% HA into the substrate, in comparation to the pristine membrane without HA doped. Besides, the average roughness of the polyamide layer was reduced by up to 68% when HA was present in the substrate, which mitigated the fouling potential. Thus, a slower flux decline ratio (~60%) was observed for the membrane modified with 0.8 wt% HA than the pristine membrane (~80%). Taken together, our findings shed light on using natural-available HA for effectively and efficiently modifying membrane substrate to simultaneously enhance the permeate-selectivity performance and the anti-fouling behavior in FO membrane process. The fundamental causes of these differences in membrane separation performance and fouling behavior are considered and related to the physical and chemical characteristics of support layer (i.e., porosity and pore size) and polyamide layer (i.e., active layer thickness and roughness) of membranes.


Asunto(s)
Filtración , Sustancias Húmicas , Membranas Artificiales , Purificación del Agua , Nylons/química , Ósmosis , Permeabilidad , Polímeros/química , Sulfonas/química , Purificación del Agua/métodos
14.
Water Res ; 145: 146-152, 2018 11 15.
Artículo en Inglés | MEDLINE | ID: mdl-30130675

RESUMEN

Membrane fouling remains a major challenge for applying membrane technology to water treatment and, therefore, new tools to recognize the key foulants are essential for characterizing and evaluating the membrane fouling process. In this work, fluorescence excitation emission matrix coupled with parallel factor framework-clustering analysis was used to investigate the membrane fouling during the filtration process of humic acid (HA) and bovine serum albumin (BSA) solution by polyvinylidene fluoride membrane. Interestingly, the interaction between BSA and HA in the membrane fouling process was observed, and was further confirmed by infrared microspectroscopy and two-dimensional correlation spectroscopic analysis. In addition, the HA-induced membrane fouling was observed to be initially relieved, but became aggravated when a certain amount of BSA was added. Furthermore, with such an integrated approach, the OH groups in HA and amide bands in BSA were found to be mainly responsible for the membrane fouling and the HA-BSA interaction was mainly caused by the encapsulation of BSA with HA. This work develops a new method for probing membrane fouling and demonstrates the interaction between membrane foulants and its roles in membrane fouling process. Furthermore, the integrated approach developed in this work has a potential to explore other types of interfacial interactions.


Asunto(s)
Sustancias Húmicas , Purificación del Agua , Membranas , Membranas Artificiales , Albúmina Sérica Bovina , Ultrafiltración
15.
J Thorac Dis ; 10(5): 2991-2998, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29997966

RESUMEN

BACKGROUND: Advanced non-small cell lung cancer (NSCLC) patients who harbor anaplastic lymphoma kinase (ALK) rearrangement are sensitive to an ALK inhibitor (crizotinib), but not all ALK-positive patients benefit equally from crizotinib treatment. We analyze the impact of TP53 mutations on response to crizotinib in patients with ALK rearrangement NSCLC. METHODS: Sixty-six ALK rearrangement NSCLC patients receiving crizotinib were analyzed. 21 cases were detected successfully by the next generation sequencing validation FFPE before crizotinib. TP53 mutations were evaluated in 8 patients in relation to disease control rate (DCR), objective response rate (ORR), progression-free survival (PFS) and overall survival (OS). RESULTS: TP53 mutations were observed in 2 (25.00%), 1 (12.50%), 1 (12.50%) and 4 (50.00%) patients in exons 5, 6, 7 and 8, respectively. The majority of patients were male (75.00%, 6/8), less than 65 years old (62.50%, 5/8) and never smokers (75.00%, 6/8). ORR and DCR for crizotinib in the entire case series were 61.90% and 71.43%, respectively. Statistically significant difference was observed in terms of PFS and OS between TP53 gene wild group and mutation group patients (P=0.038, P=0.021, respectively). CONCLUSIONS: TP53 mutations reduce responsiveness to crizotinib and worsen prognosis in ALK rearrangement NSCLC patients.

16.
Water Res ; 123: 216-223, 2017 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-28672206

RESUMEN

Maximizing the energy-profitable treatment of municipal wastewater (MW) is of significance to achieve energy-neutral operation for wastewater treatment plant. Direct membrane filtration technology has been considered as an effective way to separate organic carbon from MW for subsequent anaerobic energy-recovering process, but its application is restrained by severe membrane fouling issues. Thus, it is essential to identify the substances in MW that are responsible for membrane fouling and find out efficient anti-fouling methods. In this work, an integrated approach through combining multivariate curve resolution-alternating least squares analysis with infrared attenuated total reflection mapping was adopted to explore the membrane fouling process, and three coagulants, i.e., polyacrylamide, Al2(SO4)3 and FeCl3, were individually used to mitigate membrane fouling. Results show that the 1-8 µm biopolymer clusters, i.e., humic-like and protein-like substances, were the predominant foulants in MW. In addition, membrane fouling caused by proteins was found to be more severe than that by humic substances. Coagulation pretreatment was demonstrated to be effective in mitigating membrane fouling. Al2(SO4)3 or FeCl3 had superior anti-fouling performance comparing to that of polyacrylamide. The dosage of polyacrylamide needs to be optimized according to the actual MW characteristics as its overdose would cause a substantial decline of membrane flux. These results provide a deep understanding of the membrane fouling mechanisms for organic carbon separation from MW and are beneficial for developing efficient and cost-effective membrane fouling mitigation strategies.


Asunto(s)
Membranas Artificiales , Eliminación de Residuos Líquidos , Purificación del Agua , Filtración , Membranas , Aguas Residuales
17.
Water Res ; 113: 89-96, 2017 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-28199866

RESUMEN

Polyvinylidene fluoride (PVDF) membrane has been widely applied in water and wastewater treatment because of its high mechanical strength, thermal stability and chemical resistance. However, the hydrophobic nature of PVDF membrane makes it readily fouled, substantially reducing water flux and overall membrane rejection ability. In this work, an in-situ blending modifier, i.e., extracellular polymeric substances (EPS) from activated sludge, was used to enhance the anti-fouling ability of PVDF membrane. Results indicate that the pure water flux of the membrane and its anti-fouling performance were substantially improved by blending 8% EPS into the membrane. By introducing EPS, the membrane hydrophilicity was increased and the cross section morphology was changed when it interacted with polyvinl pyrrolidone, resulting in the formation of large cavities below the finger-like pores. In addition, the fraction of pores with a size of 100-500 nm increased, which was also beneficial to improving membrane performance. Surface thermodynamic calculations indicate the EPS-functionalized membrane had a higher cohesion free energy, implying its good pollutant rejection and anti-fouling ability. This work provides a simple, efficient and cost-effective method to improve membrane performance and also extends the applications of EPS.


Asunto(s)
Reactores Biológicos , Aguas del Alcantarillado/química , Biopolímeros/química , Membranas Artificiales , Polímeros
18.
World J Gastrointest Pathophysiol ; 1(4): 137-43, 2010 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-21607154

RESUMEN

Intestinal ischemia is a severe disorder with a variety of causes. Reperfusion is a common occurrence during treatment of acute intestinal ischemia but the injury resulting from ischemia/reperfusion (IR) may lead to even more serious complications from intestinal atrophy to multiple organ failure and death. The susceptibility of the intestine to IR-induced injury (IRI) appears from various experimental studies and clinical settings such as cardiac and major vascular surgery and organ transplantation. Whereas oxygen free radicals, activation of leukocytes, failure of microvascular perfusion, cellular acidosis and disturbance of intracellular homeostasis have been implicated as important factors in the pathogenesis of intestinal IRI, the mechanisms underlying this disorder are not well known. To date, increasing attention is being paid in animal studies to potential pre- and post-ischemia treatments that protect against intestinal IRI such as drug interference with IR-induced apoptosis and inflammation processes and ischemic pre-conditioning. However, better insight is needed into the molecular and cellular events associated with reperfusion-induced damage to develop effective clinical protection protocols to combat this disorder. In this respect, the use of ischemic post-conditioning in combination with experimentally prolonged acidosis blocking deleterious reperfusion actions may turn out to have particular clinical relevance.

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