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1.
Oncol Rep ; 47(3)2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35039878

RESUMO

Therapeutic approaches that target the metabolism of tumor cells have been a popular research topic in recent years. Previous studies have demonstrated that glycolysis inhibitors reduce the proliferation of non­small cell lung cancer (NSCLC) cells by interfering with the aerobic glycolytic pathway. However, the mitochondrial oxidative phosphorylation (OXPHOS) pathway in tumor cells has also been implicated in lung cancer metabolism. Metformin, a known inhibitor of mitochondrial OXPHOS, has been indicated to reduce NSCLC morbidity and mortality in clinical studies. The present article reviewed the therapeutic effects of metformin against NSCLC, both as a single agent and combined with other anticancer treatments, in order to provide a theoretical basis for its clinical use in adjuvant therapy for NSCLC.

2.
Food Chem ; 377: 132021, 2022 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-34999456

RESUMO

In this study, a convenient and economic method for the determination of fipronil and its three metabolites in edible oil was developed based on pollen grain solid-phase extraction (SPE). As a natural material, pollen grains exhibit well absorption capacity for some polar compounds due to their special functional structures. Their stable composition and appropriate particle size also make them suitable for SPE. In the present study, natural pine pollen grains without broken wall were used as sorbent for selective isolation and enrichment of fipronil and its three metabolites from edible oils based on hydrogen bond interaction. Several parameters influencing the extraction recoveries were investigated. By coupling with gas chromatography-electron capture detection (GC-ECD), a new method for analysis of fipronil and its metabolites in edible oils was established. The linearity range was 2-200 ng/g with correlation coefficient R2 more than 0.999. The recoveries in edible oils at three spiked concentrations were in the range of 80.1-96.0% with the RSDs less than 10.6% (intra-day) and 11.5% (inter-day). The limit of detection (LOD) for four target analytes were in the range of 0.2-0.6 ng/g, which was comparable to the previous reported methods. Finally, the established method was successfully applied to detect fipronil and its metabolites in several oil samples with different brands from local market.

3.
Plant Signal Behav ; : 2024738, 2022 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-35034577

RESUMO

DEK is associated with DNA replication and break repair, mRNA splicing, and transcriptional regulation, which had been studied in humans and mammals. The function of DEK in plants was poorly understood. In this study, GhDEK2D was identified in Gossypium hirsutum by genome-wide and post-translational modifications. GhDEK2D had been phosphorylated, acetylated and ubiquitylated under Verticillium dahliae (Vd) challenge. The GhDEK2D-silenced cotton decreased resistance against Vd. In GhDEK2D-silenced cotton plants, the reactive oxygen species was activated, the callose, xylogen, hypersensitive reaction (HR) and expression levels of defense-related genes were reduced. Homozygous overexpressing-GhDEK2D transgenic Arabidopsis lines were more resistant to Verticillium wilt (Vw). We propose that GhDEK2D was a potential molecular target for improving resistance to Vw in cotton.

4.
J Air Waste Manag Assoc ; : 0, 2022 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-35037589

RESUMO

Redundant stations in the air quality monitoring network (AQMN), not only cause high maintenance and operation costs, but also affect the performance of air quality assessment. This study presents a novel framework for identifying the redundant stations and selecting the corresponding alternatives in AQMN. The framework composes three main steps. Firstly, we identify the redundant stations by correlation analysis and stepwise regression methods. Secondly, we determine the corresponding alternative stations by cluster analysis and correspondence analysis methods. Finally, the final optimization results are verified by the support vector regression. We perform empirical evaluations of the framework using Shanghai's AQMN. The results show that Xuhui, Zhangjiang, Shiwuchang, and Pudong New Area are four redundant pollution monitoring stations. Alternatives for each type of pollutant for these redundant stations are proposed and the adjusted layout of AQMN is verified with historical data. The framework proposed in this study can effectively improve the layout of AQMN, which could be applied to other cities or regions to improve the integrity of pollution information and reduce the monitoring costs.

5.
BMC Infect Dis ; 22(1): 17, 2022 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-34983415

RESUMO

BACKGROUND: Concerns regarding potential toxicity and drug-drug interactions during long-term treatment with three-drug active antiretroviral therapy (ART) regimens have been attracting increasing attention. We aimed to evaluate the efficacy and safety of dolutegravir (DTG) plus lamivudine (3TC) in ART-naive adults in China. METHODS: This prospective observational cohort study enrolled HIV-naive inpatients treated with DTG + 3TC (2DR arm) or efavirenz (EFV) plus tenofovir disoproxil fumarate (TDF) and 3TC (3DR arm). There were no limits on baseline viral load. Inflammatory biomarkers were also investigated in the 2DR arm. RESULTS: Between September 2019 and January 2020, 27 patients treated with DTG + 3TC and 28 patients treated with EFV + TDF + 3TC were enrolled in the study. At week 12, the proportion of patients with viral loads < 50 copies/mL in the 2DR arm was 81.5% (22/27) compared with 53.6% (15/28) in the 3DR arm (p < 0.01). At week 24, the proportion of patients with viral loads < 50 copies/mL in the 2DR arm was 100% (26/26) compared with 83.3% (20/24) in the 3DR arm (p < 0.05). Mean changes in CD4 cell counts from baseline at week 12 were 125.46 cells/µL in the 2DR arm and 41.20 cells/µL in the 3DR arm (p < 0.05). Mean changes in CD4 cell counts from baseline at week 24 were 209.68 cells/µL in the 2DR arm and 73.28 cells/µL in the 3DR arm (p < 0.05). CONCLUSIONS: DTG + 3TC achieved virologic suppression more rapidly than EFV + TDF + 3TC after 12 and 24 weeks. DTG + 3TC could represent an optimal regimen for advanced patients. Clinical Trial Registration ChiCTR1900027640 (22/November/2019).


Assuntos
Fármacos Anti-HIV , Infecções por HIV , HIV-1 , Alcinos , Fármacos Anti-HIV/efeitos adversos , Benzoxazinas/efeitos adversos , Ciclopropanos , Infecções por HIV/tratamento farmacológico , Compostos Heterocíclicos com 3 Anéis , Humanos , Lamivudina/uso terapêutico , Oxazinas , Piperazinas , Estudos Prospectivos , Piridonas , Tenofovir/uso terapêutico
6.
Cell Death Dis ; 13(1): 72, 2022 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-35064107

RESUMO

Gastric cancer (GC) is the fifth most common tumor and the third most deadly cancer worldwide. N6-methyladenosine (m6A) modification has been reported to play a regulatory role in human cancers. However, the exact role of m6A in GC remains largely unknown, and the dysregulation of m6A on mitochondrial metabolism has never been studied. In the present study, we demonstrated that FTO, a key demethylase for RNA m6A modification, was up-regulated in GC tissues, especially in tissues with liver metastasis. Functionally, FTO acted as a promoter for the proliferation and metastasis in GC. Moreover, FTO enhanced the degradation of caveolin-1 mRNA via its demethylation, which regulated the mitochondrial fission/fusion and metabolism. Collectively, our current findings provided some valuable insights into FTO-mediated m6A demethylation modification and could be used as a new strategy for more careful surveillance and aggressive therapeutic intervention.

7.
Sci Total Environ ; : 153287, 2022 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-35066031

RESUMO

Assessing the adverse health risks at molecular endpoints to various aquatic organisms could be an urgent issue. In this manuscript, the ecological and AhR-mediated risk of sixteen polycyclic aromatic hydrocarbons (PAHs) and six polybrominated diphenyl ethers (PBDEs) in surface water of Dongjiang River, Southern China was evaluated using chemical analysis and in silico approaches. Average concentrations of ∑16PAHs and ∑6PBDEs were 586.3 ng/L and 2.672 ng/L in the dry season (DS), and 366.8 ng/L and 2.554 ng/L in the wet season (WS). Concentrations of PAHs during the DS were significantly higher than that in the WS, while no obvious seasonal distribution was observed for PBDEs. Only Ant and BaP in all congers of PAHs posed low to medium ecological risks, and PBDEs posed a low ecological risk. Moreover, AhR-mediated risk from PAHs was two orders of magnitude higher that from PBDEs, and the AhR-mediated toxicity on frog and eel were higher than those on other aquatic organisms in Dongjiang River. Phe and BDE209 were the significant contributor to the AhR-mediated risk induced by PAHs and PBDEs, respectively. This study is the first attempt to assess AhR-mediated risk of river water in multiple aquatic organisms.

8.
Neurosci Lett ; : 136469, 2022 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-35066091

RESUMO

OBJECTIVES: To further investigate the effects of miR-497 on the biological behavior of human medulloblastoma cell line in vitro. METHODS: Human medulloblastoma cell lines, Daoy and D341, were used in this study, and the miR-497 expression in the cells was measured by Quantitative PCR with fluorescence. The Daoy cells were divided into the mimics group (Daoy cells treated with mimics), inhibitor group (Daoy cells treated with inhibitor), normal Daoy cells, ARHGDIA siRNA group (Daoy cells transfected with ARHGDIA siRNA), ARHGDIA control group (Daoy cells did not receive any treatment), and negative control group (normal cells transfected with ARHGDIA siRNA). The expression of miR-497 and ARHGDIA mRNA was measured by Quantitative PCR with fluorescence, while the level of ARHGDIA protein was measured by Western blot. The binding capability of ARHGDIA and miR-497 was assessed by luciferase assay, the migration of cells was assessed by wound healing assay, and the invasion of cells was assessed by Transwell assay. RESULTS: Compared to D341 cells, the miR-497 level was significantly higher in the Daoy cells (P<0.01). The dual-luciferase reporter assay showed that miR-497 targets ARHGDIA. Transfecting the normal Daoy cells with miR-497 mimics significantly reduced the expression of ARHGDIA protein (P<0.05), while transfecting normal Daoy cells with miR-497 inhibitor significantly increased the expression of ARHGDIA protein (P<0.05). Consequently, the migration and invasion capability of cells increased significantly after transfection with miR-497 mimic (P<0.05), and decreased significantly after transfection with miR-497 inhibitor (P<0.05). In addition, the migration and invasion capabilities of the cells also increased significantly after transfection with ARHGDIA siRNA (P<0.05). CONCLUSIONS: miR-497/ARHGDIA axis participates in the in vitro migration and invasion of human medulloblastoma cell lines.

9.
Hepatol Int ; 2022 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-35037228

RESUMO

BACKGROUND: No reports exist regarding the prevalence of different Na levels and their relationship with 90-day prognosis in hospitalized patients with acute-on-chronic liver disease (AoCLD) in China. Therefore, the benefit of hyponatremia correction in AoCLD patients remains unclear. METHODS: We prospectively collected the data of 3970 patients with AoCLD from the CATCH-LIFE cohort in China. The prevalence of different Na levels (≤ 120; 120-135; 135-145; > 145) and their relationship with 90-day prognosis were analyzed. For hyponatremic patients, we measured Na levels on days 4 and 7 and compared their characteristics, based on whether hyponatremia was corrected. RESULTS: A total of 3880 patients were involved; 712 of those developed adverse outcomes within 90 days. There were 80 (2.06%) hypernatremic, 28 (0.72%) severe hyponatremic, and 813 (20.95%) mild hyponatremic patients at admission. After adjusting for all confounding factors, the risk of 90-day adverse outcomes decreased by 5% (odds ratio [OR] 0.95; 95% confidence interval [CI] 0.93-0.97; p < 0.001), 24% (OR 0.76; 95% CI 0.70-0.84; p < 0.001), and 42% (OR 0.58; 95% CI 0.49-0.70; p < 0.001) as Na level increased by 1, 5, and 10 mmol/L, respectively. Noncorrection of hyponatremia on days 4 and 7 was associated with 2.05-fold (hazard ratio [HR], 2.05; 95% CI, 1.50-2.79; p < 0.001) and 1.46-fold (HR 1.46; 95% CI 1.05-2.02; p = 0.028) higher risk of adverse outcomes. CONCLUSIONS: Hyponatremia was an independent risk factor for a poor 90-day prognosis in patients with AoCLD. Failure to correct hyponatremia in a week after admission was often associated with increased mortality. (ClinicalTrials.gov number: NCT02457637, NCT03641872). CLINICAL TRIAL NUMBERS: This study is registered at Shanghai www.clinicaltrials.org (NCT02457637 and NCT03641872).

10.
Signal Transduct Target Ther ; 7(1): 19, 2022 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-35046386

RESUMO

Interleukin-37b (hereafter called IL-37) was identified as fundamental inhibitor of natural and acquired immunity. The molecular mechanism and function of IL-37 in colorectal cancer (CRC) has been elusive. Here, we found that IL-37 transgenic (IL-37tg) mice were highly susceptible to colitis-associated colorectal cancer (CAC) and suffered from dramatically increased tumor burdens in colon. Nevertheless, IL-37 is dispensable for intestinal mutagenesis, and CRC cell proliferation, apoptosis, and migration. Notably, IL-37 dampened protective cytotoxic T cell-mediated immunity in CAC and B16-OVA models. CD8+ T cell dysfunction is defined by reduced retention and activation as well as failure to proliferate and produce cytotoxic cytokines in IL-37tg mice, enabling tumor evasion of immune surveillance. The dysfunction led by IL-37 antagonizes IL-18-induced proliferation and effector function of CD8+ T cells, which was dependent on SIGIRR (single immunoglobulin interleukin-1 receptor-related protein). Finally, we observed that IL-37 levels were significantly increased in CRC patients, and positively correlated with serum CRC biomarker CEA levels, but negatively correlated with the CD8+ T cell infiltration in CRC patients. Our findings highlight the role of IL-37 in harnessing antitumor immunity by inactivation of cytotoxic T cells and establish a new defined inhibitory factor IL-37/SIGIRR in cancer-immunity cycle as therapeutic targets in CRC.

11.
J Cell Mol Med ; 2022 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-35044082

RESUMO

Glioblastoma multiforme (GBM) is an aggressive form of brain tumours that remains incurable despite recent advances in clinical treatments. Previous studies have focused on sub-categorizing patient samples based on clustering various transcriptomic data. While functional genomics data are rapidly accumulating, there exist opportunities to leverage these data to decipher glioma-associated biomarkers. We sought to implement a systematic approach to integrating data from high throughput CRISPR-Cas9 screening studies with machine learning algorithms to infer a glioma functional network. We demonstrated the network significantly enriched various biological pathways and may play roles in glioma tumorigenesis. From densely connected glioma functional modules, we further predicted 12 potential Wnt/ß-catenin signalling pathway targeted genes, including AARSD1, HOXB5, ITGA6, LRRC71, MED19, MED24, METTL11B, SMARCB1, SMARCE1, TAF6L, TENT5A and ZNF281. Cox regression modelling with these targets was significantly associated with glioma overall survival prognosis. Additionally, TRIB2 was identified as a glioma neoplastic cell marker in single-cell RNA-seq of GBM samples. This work establishes novel strategies for constructing functional networks to identify glioma biomarkers for the development of diagnosis and treatment in clinical practice.

12.
Chem Commun (Camb) ; 58(5): 713-715, 2022 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-34981097

RESUMO

A bimodal probe, the erythrosine B (EB) conjugated immunoglobulin G complex (EB/IgG), has been developed for the fluorescence and synchrotron X-ray fluorescence (SXRF) imaging of dopaminergic neurons in the brain.


Assuntos
Síncrotrons
13.
J Sep Sci ; 2022 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-35029014

RESUMO

In this work, a simple and miniaturized solid-phase extraction device was constructed by connecting a commercial nylon needle filter to a syringe, which was applied for extracting 1-hydroxypyrene from a urine sample via hydrophobic and hydrogen bond interactions. The nylon membrane in the needle filter acted as the solid-phase extraction adsorbent, meanwhile, it filtered the particles in the urine sample. To obtain high extraction efficiency, key parameters influencing extraction recovery were investigated. The entire pretreatment process was accomplished within 5 min under the optimal conditions. By coupling high-performance liquid chromatography-ultraviolet, a rapid, low-cost, and convenient nylon needle filter-based method was established for the analysis of 1-hydroxypyrene in a complex urine matrix. Within the linearity range of 0.2-1000 µg/L, the method exhibited a satisfactory correlation coefficient (R = 0.9999). The limit of detection was 0.06 µg/L, and the recoveries from urine sample spiked with three concentrations (5, 20, and 100 µg/L) ranged from 105.8% to 113.1% with the relative standard deviations less than 6.7% (intra-day, n = 6) and 8.9% (inter-day, n = 4). Finally, the proposed method was successfully applied for detecting 1-hydroxypyrene in urine samples from college students, smokers, gas station workers, and chip factory workers. The detected concentration in actual urine samples ranged from 0.46 to 5.26 µg/L. Taken together, this simple and cost-effective nylon needle filter-based solid-phase extraction device showed an excellent application potential for pretreating hydrophobic analytes from aqueous samples.

14.
Bioorg Med Chem Lett ; : 128574, 2022 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-35065231

RESUMO

In this work, a series of naringenin-O-carbamate derivatives was designed and synthesized as multifunctional agents for the treatment of Alzheimer's disease (AD) through multi-target-directed ligands (MTDLs) strategy. The biological activity in vitro showed that compound 3c showed good antioxidant potency (ORAC = 1.0 eq), and it was a reversible huAChE (IC50 = 9.7 µM) inhibitor. In addition, compound 3c significantly inhibited self-induced Aß1-42 aggregation, and it could activate UPS degradation pathway in HT22 cells and clear the aggregated proteins associated with AD. Moreover, compound 3c was a selective metal chelator, and it significantly inhibited and disaggregated Cu2+-mediated Aß1-42 aggregation. Furthermore, compound 3c displayed remarkable neuroprotective effect and anti-inflammatory property. Interestingly, compound 3c displayed good hepatoprotective effect by its antioxidant activity. More importantly, compound 3c demonstrated favourable blood-brain barrier penetration in vitro and drug-like property. Therefore, compound 3c was a promising multifunctional agent for the treatment of AD.

15.
Artigo em Inglês | MEDLINE | ID: mdl-35064592

RESUMO

Eight versions of the Protocol on Prevention and Control of Coronavirus Disease 2019 (COVID-19) (the Protocol) were issued successively by the Chinese authority to guide the local responses since the first COVID-19 case appeared in Wuhan, China. This study aimed to investigate the evolution of the overall strategy and specific measures in these Protocols, and several recommendations were provided after analysing China's response to the epidemic resurgence. As a result, we found a gradual expanding trend in case surveillance, early screening, and epidemiological investigation, as well as a progressively rigorous tendency in isolation measures and close contact management. With the Protocol's guidance, China had achieved success in several recent fights against domestic COVID-19 resurgences. The city lockdown and multiple city-wide nucleic acid tests adopted were deemed necessary in COVID-19 resurgence's battle. Besides, the large-scale distance centralised quarantine, which is, quarantine in a purpose-built isolation station away from communities where people under quarantine lived, was promoted in rural areas. China's anti-epidemic achievements provide ideas for the global battle against COVID-19.

16.
J Environ Manage ; 302(Pt B): 114070, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34775336

RESUMO

Understanding the impact of climate change on terrestrial wet and dry changes and the relationship between the two is of great significance to the sustainable development of terrestrial ecosystems. The farming-pastoral ecotone of northern China (FPENC) is an area that is sensitive to climate change, suffering from perennial drought and a clear aridification trend. Unlike previous single-factor, single-timescale studies, we identified aridification in the region based on a dataset established by remote sensing and ground-based monitoring stations from a combination of two perspectives: climate and soil. The results show that, in terms of climate, the period from 2000 to 2019 was the driest in the region during the last 120 years , and the summer drought was the most severe and shifted from a summer to spring drought; in terms of soil, the soil aridification trend in the region was severe, with 16.1% of the areas becoming significantly drier (P < 0.1) among the years and 41.6% in spring, respectively. Similar to climate change, soils exhibited recessive aridification due to the counterbalancing effect of the dry and wet seasons within the year. Then the coupling relationship between climate change and soil aridification was established in time and space. Moreover, the spatiotemporal response patterns of both were obtained. The results showed that the frequency of soil drought under meteorological drought conditions showed an increasing trend and that the sensitivity of soil drought occurrence increased. Among them, the effect of precipitation on relative soil moisture (RSM) was immediate, and the effect of prolonged warming on RSM is greater. The area of soil aridification that was caused by climatic aridification in spring accounted for 13.7% of the entire area. The regional aridification research mode proposed in this paper can provide ideas for subsequent studies.


Assuntos
Ecossistema , Solo , Agricultura , China , Mudança Climática
17.
Spectrochim Acta A Mol Biomol Spectrosc ; 266: 120467, 2022 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-34637988

RESUMO

A novel Au NPs/GeO2 nanozymes are developed as Surface-Enhanced Raman Scattering (SERS) substrates with the promising prospect for detection ChI. Herein, it is discovered that both Au NPs and GeO2 nanozymes have peroxidase-like activity, catalyzing colorless 3,3',5,5'-tetramethylbenzidine (TMB) to produce blue TMBox. Interestingly, compared with single Au NPs or GeO2 nanozymes, the Au NPs/GeO2 nanozymes show stronger peroxidase-like activity, and significantly ameliorated SERS signal of TMBox. The mentioned two enhancements are ascribed to a positive synergistic function of Au NPs/GeO2 nanozymes. Surprisingly, choline iodide (ChI) can inhibit the positive synergy in Au NPs/GeO2 nanozymes, and slow down the reaction of TMB-H2O2-Au NPs/GeO2 system. On this foundation, a new Au NPs/GeO2 SERS technique with high sensitivity, label-free detection method of choline iodide (ChI) is established, suggesting that Au NPs/GeO2 nanozymes have the potential application of water environment.


Assuntos
Ouro , Nanopartículas Metálicas , Colina , Peróxido de Hidrogênio , Iodetos , Peroxidase , Peroxidases , Análise Espectral Raman
18.
Int Immunopharmacol ; 103: 108498, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34972067

RESUMO

The mechanisms that control B cell terminal differentiation remain undefined. Here, we investigate the role of bromodomain-containing protein 4 (Brd4) in regulating B cell differentiation and its therapeutic potential for B cell-mediated autoimmune diseases including systemic lupus erythematosus (SLE). We showed that Brd4 inhibitor PFI-1 suppressed plasmablast-mediated plasma cell differentiation in healthy human CD19+ B cells. PFI-1 reduced IgG and IgM secretion in costimulation-induced human B cells. We also observed a reduced percentage of plasma cells in mice with B cell-specific deletion of the Brd4 gene (Brd4flox/floxCD19-cre+). Mechanistically, using the luciferase reporter assay and the chromatin immunoprecipitation, we explored that Brd4 regulates the expression of B lymphocyte-induced maturation protein 1 (BLIMP1), an important transcript factor that is involved in modulation of plasma cell differentiation. Interestingly, PFI-1 decreased the percentages of plasmablasts and plasma cells from patients with SLE. PFI-1 administration reduced the percentages of plasma cells, hypergammaglobulinemia, and attenuated nephritis in MRL/lpr lupus mice. Pristane-injected Brd4flox/floxCD19-cre+ mice exhibited improved nephritis and reduced percentages of plasma cells. These findings suggest an essential factor of Brd4 in regulating plasma cell differentiation. Brd4 inhibition may be a potential strategy for the treatment of B cell-associated autoimmune disorders.

19.
J Environ Sci (China) ; 111: 175-184, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34949347

RESUMO

Herein, a series of niobium oxide supported cerium nanotubes (CeNTs) catalysts with different loading amount of Nb2O5 (0-10 wt.%) were prepared and used for selective catalytic reduction of NOx with NH3 (NH3-SCR) in the presence of CH2Cl2. Commercial V2O5-WO3-TiO2 catalyst was also prepared for comparison. The physcial properties and chemical properties of the Nb2O5 loaded cerium nanotubes catalysts were investigated by X-ray diffractometer, Transmission electron microscope, Brunauer-Emmett-Teller specific surface area, H2-temperature programmed reduction, NH3-temperature programmed desorption and X-ray photoelectron spectroscopy. The experiment results showed that the loading amount of Nb2O5 had a significant effect on the catalytic performance of the catalysts. 10 wt.% Nb-CeNTs catalyst presented the best NH3-SCR performance and degradation efficiency of CH2Cl2 among the prepared catalysts, due to its superior redox capability, abundant surface oxygen species and acid sites, the interaction between Nb and Ce, higher ratio of Nb4+/(Nb5++ Nb4+) and Ce3+/(Ce3+ + Ce4+), as well as the special tubular structure of cerium nanotube. This study may provide a practical approach for the design and synthesis of SCR catalysts for the simultaneously removal NOx and chlorinated volatile organic compounds (CVOCs) emitted from the stationary industrial sources.


Assuntos
Cério , Nanotubos , Amônia , Catálise , Cloreto de Metileno , Nióbio , Oxirredução , Titânio
20.
Bioact Mater ; 7: 242-253, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34466730

RESUMO

Bone regeneration is a crucial part in the treatment of periodontal tissue regeneration, in which new attempts come out along with the development of nanomaterials. Herein, the effect of cerium oxide nanoparticles (CeO2 NPs) on the cell behavior and function of human periodontal ligament stem cells (hPDLSCs) was investigated. Results of CCK-8 and cell cycle tests demonstrated that CeO2 NPs not only had good biocompatibility, but also promoted cell proliferation. Furthermore, the levels of alkaline phosphatase activity, mineralized nodule formation and expressions of osteogenic genes and proteins demonstrated CeO2 NPs could promote osteogenesis differentiation of hPDLSCs. Then we chose electrospinning to fabricate fibrous membranes containing CeO2 NPs. We showed that the composite membranes improved mechanical properties as well as realized release of CeO2 NPs. We then applied the composite membranes to in vivo study in rat cranial defect models. Micro-CT and histopathological evaluations revealed that nanofibrous membranes with CeO2 NPs further accelerated new bone formation. Those exciting results demonstrated that CeO2 NPs and porous membrane contributed to osteogenic ability, and CeO2 NPs contained electrospun membrane may be a promising candidate material for periodontal bone regeneration.

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