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1.
Biomed Res Int ; 2020: 5040521, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32016115

RESUMO

Objective: The role of telemonitoring interventions (TIs) for chronic obstructive pulmonary disease (COPD) has been studied in many systematic reviews (SRs) and meta-analyses (MAs), but robust conclusions have not been reached due to wide variations in scopes, qualities, and outcomes. The aim of this overview was to determine the effectiveness of TIs on COPD patients. Methods: PubMed, EMBASE, Web of Science, and Cochrane Library were searched for all reviews on the topic of TI in treating COPD from inception to July 8, 2019, without restrictions on language. According to the inclusion and exclusion criteria, the retrieved literature studies were screened to select SRs and MAs of randomized control trials (RCTs) that evaluated the effects of TIs in COPD patients. The methodological quality of SRs and MAs was assessed with the AMSTAR-2 tool, and the strength of evidence was assessed with the grades of recommendations, assessment, development, and evaluation (GRADE) system for concerned outcomes in terms of mortality, quality of life (SGRQ total scores), exercise capacity (6MWD), and exacerbation-related outcomes (hospitalizations, exacerbation rate, and emergency room visits). Results: Our overview included eight SRs and MAs published in 2011 to 2019, from 95 RCTs involving 10632 participants. After strict evaluation by the AMSTAR-2 tool, 75% of the SRs and MAs in this overview had either low or critically low methodological quality. The effects of TIs for COPD on mortality, quality of life, exercise capacity, and exacerbation-related outcomes are limited, and all of these outcomes scored either low or very low quality of evidence on the GRADE system. Conclusions: There might be insufficient evidence to support the effectiveness of TIs for COPD currently, but the results of this overview should be interpreted dialectically and prudently, and the role of TIs in COPD needs further exploration.

2.
Sci Rep ; 10(1): 1677, 2020 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-32015470

RESUMO

Plant seed germination is a crucial developmental event that has significant effects on seedling establishment and yield production. This process is controlled by multiple intrinsic signals, particularly phytohormones. The gaseous hormone ethylene stimulates seed germination; however, the genetic basis of ethylene production in maize during seed germination remains poorly understood. In this study, we quantified the diversity of germination among 14 inbred lines representing the parental materials corresponding to multiple recombinant inbred line (RIL) mapping populations. Quantitative trait loci (QTLs) controlling ethylene production were then identified in germinating seeds from an RIL population constructed from two parental lines showing differences in both germination speed and ethylene production during germination. To explore the possible genetic correlations of ethylene production with other traits, seed germination and seed weight were evaluated using the same batch of samples. On the basis of high-density single nucleotide polymorphism-based genetic linkage maps, we detected three QTLs for ethylene production in germinating seeds, three QTLs for seed germination, and four QTLs for seed weight, with each QTL explaining 5.8%-13.2% of the phenotypic variation of the trait. No QTLs were observed to be co-localized, suggesting that the genetic bases underlying the three traits are largely different. Our findings reveal three chromosomal regions responsible for ethylene production during seed germination, and provide a valuable reference for the future investigation of the genetic mechanism underlying the role of the stress hormone ethylene in maize germination control under unfavourable external conditions.

3.
J Hazard Mater ; 392: 122164, 2020 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-32086095

RESUMO

Sulfate radical (SO4•-)-based advanced oxidation processes (SR-AOPs) hold great promise for water purification due to their strong oxidizing and high selectivity. Recently, metal-organic frameworks (MOFs) as catalysts for peroxymonosulfate (PMS) activation to generate SO4•- have shown a bright future. However, the intrinsic nature of powder MOF nanocrystals, such as brittleness and poor processability, largely disturb their large-scale applications in practical. Herein, we develop an in situ growth method to prepare MOF filters. ZIF-67 in situ growth on the polyacrylonitrile (PAN) fibers lead to the ZIF-67/PAN composite fibers with high loading (up to 50 wt %). The loading ZIF-67 can retain their morphology and structure, which is comparable with that of pristine ZIF-67 powder. The ZIF-67/PAN filter demonstrates a high efficiency for organic pollutants removal by PMS activation. Furthermore, through the fabrication of filtration device, the dynamic catalysis results show the ZIF-67/PAN filter is a promising material for water purification. This work provides a new method for applying MOFs-based functional materials to practical water remediation and other separation applications.

4.
Chemosphere ; 248: 126028, 2020 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-32018109

RESUMO

As increasing demand of global reuse water, microbial desalination cell (MDC) is developed as a potential desalination approach to drive ion migration and separation through biodegradation without any additional energy. A novel, efficient, stable reactor coupled stacked MDC with upflow MDC was constructed, which was named as upflow-stacked MDC (USMDC). Compared with the traditional stacked MDC and upflow MDC, the desalination and generation performance of the USMDC was evaluated. Results showed that, after 24 h, the desalination ratio of USMDC can reach 91.9% when the external resistance was 1.5 Ω, which was 1.18 and 1.48 times higher than SMDC and UMDC, respectively. The long-term performance of the desalination efficiency was tested, which was maintained at 87.2-96.0% and stable for consecutive 120 days. Then, it was also the investigated that the relationship between desalination rate and external resistance during every period. The USMDC produced a maximum power density of 32.91 W m-3. In addition, the difference of current density between USMDC and SMDC indicates the turbulence generated by cylindrical structure could effectively decrease the internal resistance. It was also corroborated that salt concentration gradient and bipolar electrodialysis would decline the charge transfer efficiency. Accordingly, USMDC was verified having the superior desalination performance thus providing the possibility for application in wastewater reuse.

5.
Chemosphere ; 247: 125832, 2020 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-31931312

RESUMO

Anaerobic reduction of nitrobenzene (NB) can be efficiently enhanced bySupplementing withSulfide-modified nanoscale zerovalent iron (S-nZVI). In thisStudy,S/Fe ratio ofS-nZVI was further optimized for enhancing biological NB removal in anaerobicSystem amended withS-nZVI and inoculated by anaerobicSludge. The results indicated that the performance andStability of the coupled anaerobicSystem for NB reduction and aniline formation were remarkably improved byS-nZVI atS/Fe molar ratio of 0.3 (0.3S-nZVI). TheSecretion of extracellular polymericSubstances (EPS), transformation of volatile fatty acids (VFAs), yield of methane and activity ofSeveral key enzymes could be efficiently improved by 0.3S-nZVI. Furthermore,Species related to NB reduction, fermentation, electroactivity and methanogenesis could be enriched in 0.3S-nZVI coupled anaerobicSystem, with remarkable improvement in the biodiversity observed. ThisStudy demonstrated thatSulfidation would be a promising method to improve the performance of nZVI in coupled anaerobicSystems for the removal of recalcitrant nitroaromatic compounds from wastewater.

6.
Pharm Biol ; 58(1): 116-123, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31967915

RESUMO

Context: Clinical reports showed sildenafil beneficial therapy on severe chronic obstructive pulmonary disease (COPD) with pulmonary hypertension (PH) patients.Objective: The study investigated therapeutic effects of silenafil on pulmonary damage induced by cigarette smoke exposure and bacterial inhalation in rats.Materials and methods: Female Sprague-Dawley rats (200-250 g) were divided into control group (no exposure, n = 10) and exposure group (n = 50) suffered from cigarette smoke exposure and Klebsiella pneumonia inhalation for 8 weeks. Then rats were orally given normal saline (control group or model group), 2.0, 3.0, or 4.5 mg/kg sildenafil for 4 weeks, respectively. Pulmonary pressure, RVHI and morphological analysis of pulmonary vascular remodeling, respiratory functions assay, morphological analysis of pulmonary alveoli, and expression of PCNA and caspase-3 of epithelial cells in bronchioles wall were examined.Results: Compared to model rats, 2.0, 3.0, and 4.5 mg/kg sildenafil increased VT by -0.6 to 9.58%, PEF by 3.12 to 6.49%, EF50 by 0.81 to 6.50%, decreased mPAP by 4.43 to 25.58%, RVHI by 6.54 to 26.41%, showing a dose-dependent improvement. Furthermore, 4.5 mg/kg sildenafil significantly increased MAN by 39.70%, LA/CSA by 37.07%, decreased muscular pulmonary arteries by 48.00%, WT by 12.83%, MT by 22.89%, caspase-3 expression by 17.71%, and showed improvement on abnormality in lung interstitial and bronchioles by microscopy.Discussion and conclusion: Our results demonstrated that sildenafil decreased pathological changes in alveoli, bronchioles, interstitial tissue, and arterioles of rats with COPD and PH.

7.
J Hazard Mater ; 390: 122157, 2020 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-31999959

RESUMO

Fast and efficient tracking of micropollutants in aquatic environment by developing novel electrode materials is of great significance. Herein, a polyvinylpyrrolidone (PVP) assisted strategy is applied for synthesis of nitrogen doped Cu MOFs (N-Cu-MOF) for micropollutants electrochemical detection. The designed N-Cu-MOFs possess uniform octahedral shape with large surface area (1184 m2 g-1) and an average size of roughly 450 nm, exhibiting the excellent electroanalytical capability for the detection of multipollutants. In the case of dopamine (DA) and sulfonamides (SA) as typical microcontaminants, the designed N-Cu-MOFs exhibited wide linear ranges of 0.50 nM-1.78 mM and low detection limit (LOD, 0.15 nM, S/N = 3) for the determination of DA, as well as a linear range of 0.01-58.3 µM and LOD (0.003 µM, S/N = 3) for monitoring SA. The improved performance is attributed to the heteroatom introduction and good dispersion stability of N-Cu-MOF with PVP-decorated. The good electroanalytical ability of N-Cu-MOF for detection of DA and SA can provide a guide to efficient and rapid monitor other micropollutants and construct novel electrochemical sensors.

8.
J Hazard Mater ; 387: 121701, 2020 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-31767500

RESUMO

Developing high-effective catalysts with tailored composition and structure has attracted extensive attention. In this work, a serious of shape-specific Fe/Co Prussian blue analogs (PBAs), including concave, core-shell and polygonal cubes were prepared by the one-step hydrothermal reaction, which were altered by adjusting the ratio of Fe/Co in the initial reaction system. The catalytic performance toward bisphenol A (BPA) degradation was significantly affected by the ultimate structure and Fe/Co composition. Benefiting from appropriate elemental proportions, unique elemental distribution (rich Co in the core and rich Fe in the shell) and high specific surface areas, the core-shell PBAs (CSPs) exhibits significantly higher peroxymonosulfate (PMS) activation performance toward bisphenol A (BPA) degradation (96 % of removal efficiency within 2 min). The stability of the CSPs catalyst test further indicates that the Fe shell can effectively protect and inhibit the leaching of cobalt ions. Electron paramagnetic resonance (EPR) and radical quenching experiments measurement exhibited that both SO4- and OH are the main active species in the degradation process. Our work expanded new ideas of designing novel PBAs with controllable shape and specific core-shell composition with excellent catalytic performance.

9.
Plant J ; 101(2): 278-292, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31529523

RESUMO

The nutritional traits of maize kernels are important for human and animal nutrition, and these traits have undergone selection to meet the diverse nutritional needs of humans. However, our knowledge of the genetic basis of selecting for kernel nutritional traits is limited. Here, we identified both single and epistatic quantitative trait loci (QTLs) that contributed to the differences of oil and carotenoid traits between maize and teosinte. Over half of teosinte alleles of single QTLs increased the values of the detected oil and carotenoid traits. Based on the pleiotropism or linkage information of the identified single QTLs, we constructed a trait-locus network to help clarify the genetic basis of correlations among oil and carotenoid traits. Furthermore, the selection features and evolutionary trajectories of the genes or loci underlying variations in oil and carotenoid traits revealed that these nutritional traits produced diverse selection events during maize domestication and improvement. To illustrate more, a mutator distance-relative transposable element (TE) in intron 1 of DXS2, which encoded a rate-limiting enzyme in the methylerythritol phosphate pathway, was identified to increase carotenoid biosynthesis by enhancing DXS2 expression. This TE occurs in the grass teosinte, and has been found to have undergone selection during maize domestication and improvement, and is almost fixed in yellow maize. Our findings not only provide important insights into evolutionary changes in nutritional traits, but also highlight the feasibility of reintroducing back into commercial agricultural germplasm those nutritionally important genes hidden in wild relatives.

10.
11.
Angew Chem Int Ed Engl ; 59(5): 2066-2070, 2020 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-31846187

RESUMO

Carbon aerogels (CAs) with 3D interconnected networks hold promise for application in areas such as pollutant treatment, energy storage, and electrocatalysis. In spite of this, it remains challenging to synthesize high-performance CAs on a large scale in a simple and sustainable manner. We report an eco-friendly method for the scalable synthesis of ultralight and superporous CAs by using cheap and widely available agarose (AG) biomass as the carbon precursor. Zeolitic imidazolate framework-8 (ZIF-8) with high porosity is introduced into the AG aerogels to increase the specific surface area and enable heteroatom doping. After pyrolysis under inert atmosphere, the ZIF-8/AG-derived nitrogen-doped CAs show a highly interconnected porous mazelike structure with a low density of 24 mg cm-3 , a high specific surface area of 516 m2 g-1 , and a large pore volume of 0.58 cm-3 g-1 . The resulting CAs exhibit significant potential for application in the adsorption of organic pollutants.

12.
Eur Radiol ; 2019 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-31822977

RESUMO

OBJECTIVES: We sought to determine the added value of diffusion-weighted magnetic resonance imaging (DWI) in the differentiation of pelvic insufficiency fracture (PIF) from bone metastasis after radiotherapy in cervical cancer patients. METHODS: In the present study, 42 cervical cancer patients after radiotherapy with 61 bone lesions (n = 40, PIFs; n = 21, bone metastasis) were included. Conventional MRI and DWI were performed in all patients. For qualitative imaging diagnosis, two sets of images were reviewed independently by three observers, including a conventional MRI set (unenhanced T1-weighted, T2-weighted, and enhanced T1-weighted images) and a DWI set (conventional MRIs, DW images, and ADC maps). The mean ADC value of each lesson was measured on ADC maps. The diagnostic performance was assessed by using the area under the receiver operating characteristic curve (Az), and sensitivity and specificity were determined. RESULTS: For all observers, the Az value and sensitivity of the DWI set showed improvement compared with the conventional MRI set. The observer who had the least experience (3 years) demonstrated significant improvement in diagnostic performance with the addition of DWI; Az value increased from 0.804 to 0.915 (p = 0.042) and sensitivity increased from 75.0 to 92.5% (p = 0.035). The mean ADCs of the PIFs were significantly higher than the bone metastases (p < 0.001); ADC values > 0.97 × 10-3 mm2/s yielded an Az of 0.887, a sensitivity of 92.5%, and a specificity of 76.2%. CONCLUSIONS: The addition of DWI to conventional MRI improved the differentiation of PIF from bone metastasis after RT in patients with cervical cancer. KEY POINTS: • DWI showed additive value to conventional MRI in the differentiation of PIF from bone metastasis after RT. • For qualitative diagnosis, the addition of DWI can improve diagnostic performance compared with conventional MRI alone and can particularly improve the sensitivity. • Quantitative ADC assessment showed potential value for identifying PIF from bone metastasis.

13.
Trials ; 20(1): 735, 2019 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-31842969

RESUMO

BACKGROUND: The incidence, mortality, and prevalence of chronic obstructive pulmonary disease (COPD) are high in China. Acute exacerbations of COPD (AECOPD) are important events in the management of COPD because they negatively impact health status, rates of hospitalization and readmission, and disease progression. AECOPD have been effectively treated with Chinese medicine for a long time. The aim of this proposed trial is to assess the therapeutic effect of Chinese medicine (CM) on AECOPD. METHODS/DESIGN: This proposed study is a multicenter, double-blind, parallel-group randomized controlled trial (RCT). We will randomly assign 378 participants with AECOPD into two groups in a 1:1 ratio. On the basis of health education and conventional treatment, the intervention group will be treated with CM, and the control group is given CM placebo according to CM syndrome. Patients are randomized to either receive CM or placebo, 10 g/packet, twice daily. The double-blind treatment lasts for 2 weeks and is followed up for 4 weeks. The main outcome is the COPD Assessment Test; secondary outcomes are treatment failure rate, treatment success rate, length of hospital stay, AECOPD readmission rate, intubation rate, mortality, dyspnea, the 36-item Short Form Health Survey, and the COPD patient-reported outcome scale. We will document these outcomes faithfully at the beginning of the study, 2 weeks after treatment, and at the 4 weeks follow-up. DISCUSSION: This high-quality RCT with strict methodology and few design deficits will help to prove the effectiveness of CM for AECOPD. We hope this trial will provide useful evidence for developing a therapeutic schedule with CM for patients with AECOPD. TRIAL REGISTRATION: ClinicalTrials.gov, NCT03428412. Registered on 4 February 2018.

15.
Medicine (Baltimore) ; 98(44): e17807, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31689864

RESUMO

To explore a comparable method to Gd-contrast enhancement in the preoperative evaluation of anal fistula to evaluate its morphology changes.Forty-six patients with anal fistula were enrolled. Each patient acquired a 3.0T magnetic resonance imaging (MRI) routine sequence, diffusion-weighted imaging (DWI) sequence and fat suppression T1 weighted imaging (FS T1WI) contrast enhancement (CE) scanning. To record the morphology performances of the internal orifice and the fistulas on the transverse images of fat suppression T2 weighted imaging (FS T2WI), DWI, FS T2WI combined with DWI, FS T1WI Gd-CE, with the standard of the surgical pathology results. Two observers evaluated images in consensus. The conspicuity and the diagnostic performance rate were compared between the 4 imaging data sets.The consistencies of interobservers about the conspicuity scores and the diagnostic performance rates of the internal orifice and the fistula were good. The conspicuity of the internal orifice was higher for the set of FS T2WI, FS T2WI+DWI, and FS T1WI+CE than DWI. The diagnostic performance rate of the internal orifice was higher for the set of FS T2WI, FS T2WI+DWI, and FS T1WI+CE than DWI. The conspicuity of the fistula was higher for the set of FS T2WI+DWI and FS T1WI+CE than FS T2WI or DWI. There were no significantly differences between the 4 sets of FS T2WI, DWI, FS T2WI+DWI, and FS T1WI+CE in the diagnostic performance rate of the fistula.The set of FS T2WI combined with DWI was comparable to FS T1WI CE in evaluation of anal fistula morphology changes.


Assuntos
Meios de Contraste , Imagem de Difusão por Ressonância Magnética/métodos , Gadolínio , Fístula Retal/diagnóstico por imagem , Fístula Retal/patologia , Adolescente , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Cuidados Pré-Operatórios , Adulto Jovem
16.
Int J Biochem Cell Biol ; 117: 105641, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31693935

RESUMO

miR-145-5p has been reported to be downregulated and described functioning as a tumor suppressive gene in colorectal cancer (CRC), yet its detailed regulatory function and mechanism in malignant progression of the disease have not been thoroughly understood. In our study, miR-145-5p and rhomboid domain containing 1 (RHBDD1) in CRC tissues and cells were examined by qRT-PCR and western blot. MTT, colony formation, wound healing, Transwell invasion, and flow cytometry assays were performed to evaluate the malignant phenotypes of CRC cells. Xenograft tumor, qRT-PCR, and western blot assays were applied to validate the roles and mechanism of miR-145-5p in CRC in vivo. The interaction between miR-145-5p and RHBDD1 was investigated by luciferase reporter assay and western blot. The changes of the EGFR/Raf/MEK/ERK pathway were detected by western blot. We found miR-145-5p was lowly expressed and low miR-145-5p predicted poor prognosis in CRC, while RHBDD1 was greatly enhanced in CRC cells and tissues. RHBDD1 silencing resulted in inhibiting cell proliferative, invasive, and migratory potentials as well as elevating apoptotic ones in CRC cells. miR-145-5p was inversely related with RHBDD1 expression in CRC tissues. miR-145-5p was found to directly bind to RHBDD1 and restrained its expression in CRC cells. miR-145-5p overexpression repressed CRC cell proliferation, invasion, migration and induced apoptosis, and these effects were reversed by RHBDD1 upregulation. Moreover, in CRC xenograft tumor, its growth was impeded by miR-145-5p via suppressing RHBDD1. Furthermore, miR-145-5p inhibited the expression of EGFR, p-MEK1/2 and p-ERK1/2, in vitro and in vivo by targeting RHBDD1. In conclusion, our study revealed that miR-145-5p overexpression inhibited tumorigenesis in CRC by downregulating RHBDD1 via suppressing the EGFR-associated signaling pathway (EGFR/Raf/MEK/ERK cascades).

17.
Life Sci ; 237: 116893, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31606381

RESUMO

AIM: Gastric cancer (GC) is a common human malignancy tumor of digestive tract in worldwide. Physcion 8-O-ß-glucopyranoside (PG) exhibits anti-tumor effects in various cancer cells. This study aimed to explore the biological behavior effects of PG on GC cells, and determine its underlying mechanism. MATERIAL AND METHODS: The effect of PG treatment on the ferroptotic GC cell death was detected by ROS level, intracellular Fe2+ level and malondialdehyde (MDA) generation in vitro. The mRNA expression was detected by RT-qPCR. The interaction between miR-103a-3p and glutaminase 2 (GLS2) were verified by dual-luciferase reporter gene assay. Cell proliferation, invasion and migration were examined by CCK-8 and Transwell assay. Western blot was used to examine the expression of GLS2, SLC1A5 and epithelial-mesenchymal transition (EMT) related proteins. We also evaluated the influence of PG on the tumor growth and metastasis in vivo. RESULTS: PG-induced ferroptosis in GC cells through upregulating ROS level, intracellular Fe2+ level and MDA generation. Besides, PG also significantly enhanced the protein level of GLS2, which was an important transporter of glutamine to glutamate. Importantly, miR-103a-3p directly interacted with GLS2 and suppressed its expression. Mechanistically, PG treatment significantly promoted ferroptosis and anti-tumorigenesis by downregulating inhibitory effect of miR-103a-3p on GLS2 expression. CONCLUSION: Our studies confirmed that PG exerts pro-ferroptosis and anti-tumor effects in vitro and in vivo through regulating miR-103a-3p/GLS2 axis, thereby highlighting its therapeutic potential in GC.


Assuntos
Apoptose/efeitos dos fármacos , Emodina/análogos & derivados , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Glucosídeos/farmacologia , Glutaminase/metabolismo , Ferro/metabolismo , MicroRNAs/genética , Neoplasias Gástricas/patologia , Animais , Proliferação de Células/efeitos dos fármacos , Emodina/farmacologia , Feminino , Glutaminase/genética , Humanos , Peroxidação de Lipídeos/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Espécies Reativas de Oxigênio/metabolismo , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismo , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
18.
Chemosphere ; 235: 1180-1188, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31561309

RESUMO

Perfluoroalkyl and polyfluoroalkyl substances (PFASs) are a class of highly persistent contaminants with high bioaccumulation and toxicity. Our previous studies showed that perfluorooctanoic acid (PFOA) can be completely defluorinated under UV irradiation in organo-montmorillonite/indole acetic acid (IAA) system. However, there is still lack of information for the degradation mechanism and the test for wastewater treatment. Here, we systematically investigated the defluorination reaction in the presence of different organo-montmorillonites and found that the degradation process was apparently controlled by the configuration of surfactants. In hexadecyltrimethyl ammonium (HDTMA)-modified montmorillonite, HDTMA exists as a tilt conformation and isolated clay interlayer from the aqueous solution, protecting hydrated electrons generated by photo-irradiation of IAA from quenching by oxygen. Defluorination hydrogenation process was the dominant degradation pathway. While in poly-4-vinylpyridine-co-styrene (PVPcoS)-modified montmorillonite, due to the multiple charges of PVPcoS, a flat conformation parallel to clay surface was expected. Hydroxyl radicals, which were generated by the reaction of hydrated electrons with oxygen molecules diffused into clay interlayer, are also involved in the degradation process. Our results further demonstrate that mixture modified montmorillonite could combine the advantages of both modifications, thus showing superior reactivity even for actual industrial wastewater without any pretreatment. This technique would have great potential for treatment of actual wastewater.


Assuntos
Bentonita/química , Caprilatos/química , Argila/química , Elétrons , Fluorcarbonetos/química , Tensoativos/química , Adsorção , Radical Hidroxila/química , Conformação Molecular , Purificação da Água/métodos
19.
Chemosphere ; 237: 124471, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31401428

RESUMO

Inability to remove biologically toxic and persistent contaminants is a critical issue in traditional water treatment processes. In this study, a novel 3D macroporous RuO2 (3D-RuO2) electrode with uniform and interconnected cavities has been fabricated via templated electrodeposition approach for treatment of persistent pyrazole. The physicochemical properties of the electrodes are characterized by means of SEM, BET, XRD, LSV and CV measurements. The results show that structural features of the 3D-RuO2 play important roles in the electrocatalysis performance. Thanks to the abundant crystal defect sites, 3D-RuO2 electrode possesses more mesopores within the skeleton, resulting in 17.9 and 2.2 times larger specific surface area compared to traditional flat thermal-deposited (TF-RuO2) and electrodeposited RuO2 (EF-RuO2) respectively. At a current density of 5 mA cm-2, the pyrazole removal rate on 3D-RuO2 is 1.7 times and 1.3 times that of TF-RuO2 and EF-RuO2. The energy consumption for 50% of pyrazole removal on 3D-RuO2 is 0.05 kWh g-1pyrazole, much lower than that of TF-RuO2 (0.11 kWh g-1pyrazole) and EF-RuO2 (0.075 kWh g-1pyrazole). The improved removal performance of 3D-RuO2 electrode is attributed to its strong electro-adsorption capacity (270.3 µg cm-2), leading to enhanced mass transfer of pollutants to the electrode surface. The mass transfer coefficient (κm) is estimated as 2.4 × 10-6 m s-1 for 3D-RuO2, which is 3.9 and 2.3 times as much as that of TF-RuO2 and EF-RuO2. Finally, contribution of different electron transfer approaches to pyrazole degradation under anodic polarization was investigated by ROS scavenging experiments.


Assuntos
Pirazóis/química , Poluentes Químicos da Água/química , Purificação da Água/métodos , Adsorção , Eletrodos , Pirazóis/análise , Compostos de Rutênio , Águas Residuárias/análise , Água , Poluentes Químicos da Água/análise
20.
Am J Physiol Gastrointest Liver Physiol ; 317(4): G387-G397, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31411894

RESUMO

The cardiac glycoside digoxin was identified as a potent suppressor of pyruvate kinase isoform 2-hypoxia-inducible factor-α (PKM2-HIF-1α) pathway activation in liver injury mouse models via intraperitoneal injection. We have assessed the therapeutic effects of digoxin to reduce nonalcoholic steatohepatitis (NASH) by the clinically relevant oral route in mice and analyzed the cellular basis for this effect with differential involvement of liver cell subsets. C57BL/6J male mice were placed on a high-fat diet (HFD) for 10 wk and started concurrently with the gavage of digoxin (2.5, 0.5, 0.125 mg/kg twice a week) for 5 wk. Digoxin significantly reduced HFD-induced hepatic damage, steatosis, and liver inflammation across a wide dosage range. The lowest dose of digoxin (0.125 mg/kg) showed significant protective effects against liver injury and sterile inflammation. Consistently, digoxin attenuated HIF-1α sustained NLRP3 inflammasome activation in macrophages. We have reported for the first time that PKM2 is upregulated in hepatocytes with hepatic steatosis, and digoxin directly improved hepatocyte mitochondrial dysfunction and steatosis. Mechanistically, digoxin directly bound to PKM2 and inhibited PKM2 targeting HIF-1α transactivation without affecting PKM2 enzyme activation. Thus, oral digoxin showed potential to therapeutically inhibit liver injury in NASH through the regulation of PKM2-HIF-1α pathway activation with involvement of multiple cell types. Because of the large clinical experience with oral digoxin, this may have significant clinical applicability in human NASH.NEW & NOTEWORTHY This study is the first to assess the therapeutic efficacy of oral digoxin on nonalcoholic steatohepatitis (NASH) in a high-fat diet (HFD) mouse model and to determine the divergent of cell type-specific effects. Oral digoxin reduced liver damage, steatosis, and inflammation in HFD mice. Digoxin attenuated hypoxia-inducible factor (HIF)-1α axis-sustained inflammasome activity in macrophages and hepatic oxidative stress response in hepatocytes via the regulation of PKM2-HIF-1α axis pathway activation. Oral digoxin may have significant clinical applicability in human NASH.

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