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1.
Opt Lett ; 44(19): 4845-4848, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31568457

RESUMO

The nominal composition of Al2O3-Ce:Y3Mg1.8Al1.4Si1.8O12 (A-Ce:YMASG) ceramic phosphors was fabricated by the vacuum sintering technique. The introduction of Al2O3 as a second phase partially enters the crystal lattice, which was confirmed by the composition changing of the samples through x-ray diffraction measurement. An impurity phase of Y4MgSi3O13 was observed in Ce:YMASG and disappeared with the introduction of Al2O3 at the concentration of 10 wt. %. When the content of Al2O3 increased to 30 and 50 wt. %, the second phase of Al2O3 was measured with actual weight ratios of 7.72 and 20.55 wt. %, respectively. The third phase of MgAl2O4 was found with the further addition of Al2O3at 70 wt. %; the weight ratios of Ce:YMASG, Al2O3, and MgAl2O4 were 68.756, 18.457, and 12.787 wt. %, respectively. The luminescent characters of the samples were measured by the photoluminescence spectra and electroluminescent spectra. With the increase of Al2O3 from 0 to 30 wt. %, the emission wavelength of Ce3+ plummeted from 610 to 552 nm, and the luminous efficacy of the samples increased from 35 to 65 lm/W.

2.
J Biol Chem ; 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31570520

RESUMO

Cell-collagen interactions are crucial for cell migration and invasion during cancer development and progression. Heat shock protein 47 (HSP47) is an endoplasmic reticulum (ER)-resident molecular chaperone that facilitates collagen maturation and deposition. It has been previously shown that HSP47 expression in cancer cells is crucial for cancer invasiveness. However, exogenous collagen cannot rescue cell invasion in HSP47-silenced cancer cells, suggesting that other HSP47 targets contribute to cancer cell invasion. Here, we show that HSP47 expression is required for the stability and cell-surface expression of discoidin domain-containing receptor 2 (DDR2) in breast cancer tissues. HSP47 silencing reduced DDR2 protein stability, accompanied by suppressed cell migration and invasion. Co-immunoprecipitation (Co-IP) results revealed that HSP47 binds to the DDR2 ectodomain. Using a photo-convertible technique and total internal reflection fluorescence (TIRF) microscopy, we further demonstrate that HSP47 expression significantly sustains the membrane localization of the DDR2 protein. These results suggest that binding of HSP47 to DDR2 increases DDR2 stability and regulates its membrane dynamics and thereby enhances cancer cell migration and invasion. Given that DDR2 has a crucial role in the epithelial-to-mesenchymal transition and cancer progression, targeting the HSP47-DDR2 interaction might be a potential strategy for inhibiting DDR2-dependent cancer progression.

3.
Lipids ; 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31573688

RESUMO

Visceral obesity is a high-risk factor for diabetes and metabolic syndrome. Resveratrol, a natural polyphenolic compound, has been reported to inhibit preadipocyte differentiation. However, the effect of resveratrol on human visceral preadipocyte (HPA-v) differentiation remains largely unknown. LIM domain only 3 (LMO3) promotes human preadipocyte differentiation by enhancing peroxisome proliferator-activated receptor γ (PPARγ) transcriptional activity, which is the master regulator of adipogenesis. The purpose of our study was to determine the effect of resveratrol (0-50 µM) on HPA-v proliferation and differentiation, and the role of LMO3 in resveratrol-mediated regulation of HPA-v differentiation. Resveratrol inhibited HPA-v proliferation and differentiation in a dose-dependent manner, and significantly decreased the mRNA expression levels of PPARG, CCAAT/enhancer-binding protein α (CEBPA), fatty acid-binding protein 4 (FABP4), acetyl-CoA carboxylase (ACC), and fatty acid synthase (FAS) (p < 0.05) at 10, 20, and 50 µM. The mRNA and protein levels of LMO3 were significantly reduced by ≥20 µM resveratrol (p < 0.05), and overexpression of LMO3 partially attenuated resveratrol-induced reduction of HPA-v differentiation by enhancing the PPARG transcriptional activity. Together, our study suggested that resveratrol reduced HPA-v proliferation and differentiation, as well as LMO3, which was partially responsible for the reduction of resveratrol-mediated adipocyte differentiation.

4.
World J Gastroenterol ; 25(37): 5590-5603, 2019 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-31602160

RESUMO

BACKGROUND: Pancreatic cancer is a major cause of cancer-related death, with a 5-year overall survival rate being below 5%. The main causes of poor prognosis in pancreatic cancer include easy metastasis, high recurrence rate, and robust drug resistance. Gemcitabine is a first-line drug for patients with unresectable pancreatic cancer. However, due to drug resistance, the clinical effect is not satisfactory. ADAM28 is reported as a tumor promoter in some cancers, but its role in pancreatic cancer and gemcitabine chemoresistance in pancreatic cancer has not been elucidated. AIM: To identify if ADAM28 can act as an important target to reverse the gemcitabine drug resistance in pancreatic cancer. METHODS: RNA-sequence analysis was applied to explore the potential targets involved in the gemcitabine of pancreatic cancer. SW1990 pancreatic cancer cells were treated with an increased dose of gemcitabine, and the mRNA levels of ADAM28 were evaluated by RT-PCR. The protein and mRNA levels of ADAM28 were confirmed in the gemcitabine resistant and parallel SW1990 cells. The ADAM28 expression was also assessed in TCGA and GEO databases, and the results were confirmed in the collected tumor and adjacent normal tissues. The overall survival (OS) rate and relapse-free survival (RFS) rate of pancreatic cancer patients with high ADAM28 level and low ADAM28 level in TCGA were evaluated with Kaplan-Meier Plotter. Furthermore, the OS rate was calculated in pancreatic cancer patients with high tumor mutation burden (TMB) and low TMB. CCK-8 assay was used to examine the effect of ADAM28 on the viability of SW1990 cells. The ADAM28 and its co-expressed genes were analyzed in the cBioPortal for cancer genomics and subjected to GSEA pathway analysis. The correlations of ADAM28 with GSTP1, ABCC1, GSTM4, and BCL2 were analyzed based on TCGA data on pancreatic cancer. RESULTS: RNA-sequence analysis identified that ADAM28 was overexpressed in gemcitabine-resistant cells, and gemcitabine treatment could induce the expression of ADAM28. The mRNA and protein levels of ADAM28 were elevated in gemcitabine-resistant SW1990 cells compared with parallel cells. Also, the expression of ADAM28 was upregulated in pancreatic tumor tissues against normal pancreatic tissues. Notably, ADAM28 was highly expressed in the classical type than in the basal tumor type. Furthermore, the high expression of ADAM28 was associated with low OS and RFS rates. Interestingly, the high levels of ADAM28 was associated with a significantly lower OS rate in the high TMB patients, but not in the low TMB patients. Moreover, overexpression of ADAM28 could reduce the cell viability inhibition by gemcitabine, and knockdown of ADAM28 could enhance the proliferation inhibition by gemcitabine. The GSEA analysis showed that ADAM28 was related to the regulation of drug metabolism, and ADAM28 was significantly positively correlated with GSTP1, ABCC1, GSTM4, and BCL2. CONCLUSION: This study demonstrates that ADAM28 is overexpressed in pancreatic cancer, and closely involved in the regulation of gemcitabine resistance. Overexpression of ADAM28 is a novel prognostic biomarker in pancreatic cancer.

5.
Cell Death Differ ; 2019 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-31591471

RESUMO

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

6.
Clin Drug Investig ; 2019 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-31586305

RESUMO

BACKGROUND AND OBJECTIVE: Because of the narrow therapeutic window and huge inter-individual variation, the individual precision on anticoagulant therapy of warfarin is challenging. In our study, we aimed to construct a Back Propagation Neural Network (BPNN) model to predict the individual warfarin maintenance dose among Chinese patients who have undergone heart valve replacement, and validate its prediction accuracy. METHODS: In this study, we analyzed 13,639 eligible patients extracted from the Chinese Low Intensity Anticoagulant Therapy after Heart Valve Replacement database, which collected data on patients using warfarin after heart valve replacement from 15 centers all over China. Ten percent of patients who were finally enrolled in the database were used as the external validation, while the remaining were randomly divided into the training and internal validation groups at a ratio of 3:1. Input variables were selected by univariate analysis of the general linear model; 2.0, the mean value of the international normalized ratio (INR) range 1.5-2.5, was used as the mandatory variable. The BPNN model and the multiple linear regression (MLR) model were constructed by the training group and validated through comparisons of the mean absolute error (MAE), mean squared error (MSE), root mean squared error (RMSE), and ideal predicted percentage. RESULTS: Finally, 10 input variables were selected and a three-layer BPNN model was constructed. In the BPNN model, the value of MAE (0.688 mg/day and 0.740 mg/day in internal and external validation, respectively), MSE (0.580 mg/day and 0.599 mg/day in internal and external validation, respectively), and RMSE (0.761 mg/day and 0.774 mg/day in internal and external validation, respectively) were achieved. Ideal predicted percentages were high in both internal (63.0%) and external validation (59.7%), respectively. Compared with the MLR model, the BPNN model showed a higher ideal prediction percentage in the external validation group (59.7% vs. 56.6%), and showed the best prediction accuracy in the intermediate-dose subgroup (internal validation group: 85.2%; external validation group: 84.7%) and a high predicted percentage in the high-dose subgroup (internal validation group: 36.2%; external validation group: 39.8%), but poor performance in the low-dose subgroup (internal validation group: 0%; external validation group: 0.3%). Meanwhile, the BPNN model showed better ideal prediction percentage in the high-dose group than the MLR model (internal validation: 36.2% vs. 31.6%; external validation: 42.8% vs. 37.8%). CONCLUSION: The BPNN model shows promise for predicting the warfarin maintenance dose after heart valve replacement.

7.
J Chem Phys ; 151(12): 124702, 2019 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-31575190

RESUMO

As a classic ferromagnetic material, nickel has been an important research candidate used to study dynamics and interactions of electron, spin, and lattice degrees of freedom. In this study, we specifically chose a thick, 150 nm ferromagnetic nickel (111) single crystal rather than 10-20 nm thin crystals that are typically used in ultrafast studies, and we revealed both the ultrafast heating within the skin depth and the heat transfer from the surface (skin) layer to the bulk of the crystal. The lattice deformation after femtosecond laser excitation was investigated by means of 8.04 keV subpicosecond x-ray pulses, generated from a table-top laser-plasma based source. The temperature evolution of the electron, spin, and lattice was determined using a three temperature model. In addition to coherent phonon oscillations, the blast force and sonic waves, induced by the hot electron temperature gradient, were also observed by monitoring the lattice contractions during the first couple of picoseconds after laser irradiation. This study further revealed the tens of picoseconds time required for heating the hundred nanometer bulk of the Ni (111) single crystals.

8.
Plant Cell ; 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31575723

RESUMO

Guanosine-3',5'-cyclic monophosphate (cGMP) is an important regulator in eukaryotes and cGMP-dependent protein kinase (PKG) plays a key role in perceiving cellular cGMP in diverse physiological processes in animals. However, the molecular identity, property, and function of PKG in plants remain elusive. This study has identified PKG from plants and characterized its role in mediating gibberellin (GA) response in rice. PKGs from plants are structurally unique with an additional type 2C protein phosphatase (PP2C) domain. Rice PKG possesses both protein kinase and phosphatase activities, and cGMP stimulates its kinase activity but inhibits its phosphatase activity. One of PKG's targets is GAMYB, a transcription factor in GA signaling, and the dual activities of PKG catalyze the reversible phosphorylation of GAMYB at Serine6, and modulate the nucleo-cytoplasmic distribution of GAMYB in response to GA. Loss of PKG impeded the nuclear-localization of GAMYB and abolished GAMYB function in GA response, leading to defects in GA-induced seed germination, internode elongation, and pollen viability. In addition to GAMYB, the results indicate that PKG has broader effects with multiple potential targets in particular involved in salt stress response.

9.
Adv Mater ; : e1904762, 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31566289

RESUMO

Wrinkled hydrogels from biomass sources are potential structural biomaterials. However, for biorelated applications, engineering scalable, structure-customized, robust, and biocompatible wrinkled hydrogels with highly oriented nanostructures and controllable intervals is still a challenge. A scalable biomass material, namely cellulose, is reported for customizing anisotropic, all-cellulose, wrinkle-patterned hydrogels (AWHs) through an ultrafast, auxiliary force, acid-induced gradient dual-crosslinking strategy. Direct immersion of a prestretched cellulose alkaline gel in acid and relaxation within seconds allow quick buildup of a consecutive through-thickness modulus gradient with acid-penetration-directed dual-crosslinking, confirmed by visual 3D Raman microscopy imaging, which drives the formation of self-wrinkling structures. Moreover, guided by quantitative mechanics simulations, the structure of AWHs is found to exhibit programmable intervals and aligned nanostructures that differ between ridge and valley regions and can be controlled by tuning the prestretching strain and acid treatment time, and these AWHs successfully induce cell alignment. Thus, a new avenue is opened to fabricate polysaccharide-derived, programmable, anisotropic, wrinkled hydrogels for use as biomedical materials via a bottom-up method.

10.
Chem Commun (Camb) ; 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31566632

RESUMO

The non-aqueous solvent formed by 2-piperidineethanol (2-PE) and ethylene glycol (EG) exhibited a high CO2 capacity of up to 0.97 mol CO2 per mol amine at 25 °C and 1.0 atm and a low regeneration temperature of 50 °C, indicating the low energy consumption in the regeneration process. Surprisingly, CO2 directly reacted with EG by forming a carbonate species, proved by FTIR and NMR results.

12.
Artigo em Inglês | MEDLINE | ID: mdl-31564093

RESUMO

Phosphorus (P)-doping in vacancies of graphene sheets can significantly change graphene's physical and chemical properties. Generally, a high P-doping level is difficult due to the low concentration of vacancy, but is needed to obtain graphene with the desired properties. Here, we report the synthesis of P-superdoped graphene (PG) with the very high P content of 6.40 at.% by thermal annealing of fluorographite (FGi) in P vapour. Moreover, we show that the P-doping level can be tuned in the wide range from 2.86 to 6.40 at.% by changing the mass ratio of red phosphorus to FGi. The magnetic results show that (i) P-doping can effectively create localized magnetic moments in graphene; (ii) the higher doping level of sp3-type POx groups, the higher magnetization of PG; and (iii) the high P-doping levels can lead to the coexistence of antiferromagnetic and ferromagnetic behavior. It is proposed that the sp3-type POx groups are the major magnetic sources.

13.
Artigo em Inglês | MEDLINE | ID: mdl-31580067

RESUMO

Covalent organic frameworks (COFs) have obtained considerable interest because of their advanced applications. However, their low dispersibility and aqueous stability are intractable issues limiting their biomedical application. To address the issue, water-dispersible nanocomposites (COF@IR783) produced through the assembly of cyanines and COFs are proposed and prepared. Therefore, a strategy of "killing three birds with one stone" is developed. First, the nanocomposites exhibit superior dispersibility and aqueous stability compared to COFs. The nanocomposites have a nano-sized morphology and negative charges, which are beneficial in realizing long-term circulation properties and enhanced permeability and retention (EPR) mediated tumor targeted delivery for in vivo application. Secondly, the nanocomposites have enhanced photothermal therapy (PTT) ability in the near-infrared region compared to cyanines. The nanocomposites also have photoacoustic (PA) imaging ability, which can guide the antitumor therapy in vivo. Lastly, the nanocomposites can be further used as drug-delivery carriers for loading the anticancer cis-aconityl-doxorubicin (CAD) prodrug. In comparison with individual PTT or chemotherapy, the combination of PTT and chemotherapy achieved with COF@IR783@CAD synergistically induced the death of cancer cells in vitro, and intravenous injection of COF@IR783@CAD in mice resulted in significant tumor ablation. This work indicates that the dispersibility and aqueous stability of COFs can be appropriately overcome through rational design and can further expand the biomedical applications of COFs.

14.
Adv Mater ; : e1903663, 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31566837

RESUMO

Circulating rare cells in the blood are of great significance for both materials research and clinical applications. For example, circulating tumor cells (CTCs) have been demonstrated as useful biomarkers for "liquid biopsy" of the tumor. Circulating fetal nucleated cells (CFNCs) have shown potential in noninvasive prenatal diagnostics. However, it is technically challenging to detect and isolate circulating rare cells due to their extremely low abundance compared to hematologic cells. Nanostructured substrates offer a unique solution to address these challenges by providing local topographic interactions to strengthen cell adhesion and large surface areas for grafting capture agents, resulting in improved cell capture efficiency, purity, sensitivity, and reproducibility. In addition, rare-cell retrieval strategies, including stimulus-responsiveness and additive reagent-triggered release on different nanostructured substrates, allow for on-demand retrieval of the captured CTCs/CFNCs with high cell viability and molecular integrity. Several nanostructured substrate-enabled CTC/CFNC assays are observed maturing from enumeration and subclassification to molecular analyses. These can one day become powerful tools in disease diagnosis, prognostic prediction, and dynamic monitoring of therapeutic response-paving the way for personalized medical care.

15.
Nat Commun ; 10(1): 4380, 2019 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-31558716

RESUMO

Production of ammonia is currently realized by the Haber-Bosch process, while electrochemical N2 fixation under ambient conditions is recognized as a promising green substitution in the near future. A lack of efficient electrocatalysts remains the primary hurdle for the initiation of potential electrocatalytic synthesis of ammonia. For cheaper metals, such as copper, limited progress has been made to date. In this work, we boost the N2 reduction reaction catalytic activity of Cu nanoparticles, which originally exhibited negligible N2 reduction reaction activity, via a local electron depletion effect. The electron-deficient Cu nanoparticles are brought in a Schottky rectifying contact with a polyimide support which retards the hydrogen evolution reaction process in basic electrolytes and facilitates the electrochemical N2 reduction reaction process under ambient aqueous conditions. This strategy of inducing electron deficiency provides new insight into the rational design of inexpensive N2 reduction reaction catalysts with high selectivity and activity.

16.
Microbiol Immunol ; 2019 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-31552680

RESUMO

Specific tumor microenvironment signaling might prevent the maturation of dendritic cells (DCs) with tolerogenic and immunosuppressive potential accounting for antigen-specific unresponsiveness in the lymphoid organs and in the periphery. In the present study, dendritic cells treated with LLC lung cancer cell or 4T1 breast cancer cell culture supernatants significantly down-regulated the expression of co-stimulatory molecules MHC-II, CD40, CD80, but up-regulated the inhibitory molecule PD-L1/L2, VISTA, and increased the messengerRNA levels of interleukin (IL)-6, arginase I, and IL-10, but decreased tumor necrosis factor-α and IL-12a. RNA was isolated from the dendritic cells with or without tumor supernatant stimulation and RNA sequencing was done. Then the differential expression genes were sorted, the candidate genes were analyzed and pathway enrichment analysis was done, and the associated protein-protein interaction network (PPI) was established. After integrated bioinformatical analysis, 405 (279 up-regulated and 126 down-regulated) consistently differential expression genes were identified. Using gene ontology and pathway analysis, it was found that differential expression genes were mainly enriched in the immune response, cell-cell interaction, hemostasis, and cell surface interactions with the vascular wall. The PPI data demonstrated that 236 nodes were classified with 1072 edges, and the most remarkable three modules involved 53 central node genes associated with cell survival, cell-substrate adhesion, chemotaxis, migration, immune response, and complement receptor mediated signaling pathway. These findings revealed the immune status of dendritic cells in the tumor environment.

17.
Environ Int ; 133(Pt A): 105157, 2019 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-31520959

RESUMO

Electrochemical degradation of trace antiretroviral drug stavudine was investigated by using a reactive electrochemical membrane (REM) with Ti/SnO2-Sb anode. From the results it was evident that the stavudine degradation followed pseudo-first-order kinetics, with the values of the degradation rate constant and half-life being 0.24 min-1 and 2.9 min, respectively, at a current density of 8 mA cm-2. The degradation rate was obviously decreased under alkaline condition (pH = 11.0) and the degradation was also inhibited in the presence of NO3- and Cl-. Five intermediates were identified in the electrochemical degradation of stavudine, and the degradation pathways were proposed. Density functional theory calculation revealed that the double bond carbon atom nearby hydroxymethyl group was the site attacked by OH and the cleavage of CN bond was the rate-determining step in the electrochemical degradation of stavudine. The nitrogen in stavudine was mainly converted to nitrate and ammonium. Quantitative structure-activity relationship model indicated that the toxicity of some intermediates was higher than the parent compound stavudine. The electric energy consumption for 90% stavudine degradation ranged from 0.87 to 2.29 Wh L-1 at the experimental conditions, indicating that stavudine can be degraded efficiently by the REM with Ti/SnO2-Sb anode.

18.
Environ Int ; 133(Pt A): 105154, 2019 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-31521816

RESUMO

2,2',4,4'-Tetrabromodiphenyl ether (BDE-47), a predominant polybrominated diphenyl ether (PBDE), has received extensive attention for its potential environmental impact. An integrated study of metabolomics and transcriptomics was conducted on two rice (Oryza sativa) cultivars, Lianjing-7 (LJ-7) and Yongyou-9 (YY-9), which have been identified as tolerant and sensitive cultivars to BDE-47, respectively. The objective was to investigate the molecular mechanisms of their different ability to tolerate BDE-47. Both rice plants were cultivated to maturity in soils containing three concentrations of BDE-47 (10, 20, and 50 mg/kg). Metabolomic analyses of rice grains identified 65 metabolites in LJ-7 and 45 metabolites in YY-9, including amino acids, saccharides, organic acids, fatty acids, and secondary metabolites. In the tolerant cultivar LJ-7 exposed to 50 mg/kg BDE-47, concentrations of most of the metabolites increased significantly, with α-ketoglutaric acid increased by 20-fold and stigmastanol increased by 12-fold. In the sensitive cultivar YY-9, the concentrations of most metabolites increased after the plant was exposed to 1 and 10 mg/kg BDE-47 but decreased after the plant was exposed to 50 mg/kg BDE-47. Transcriptomic data demonstrated that regulation of gene expressions was affected most in LJ-7 exposed to 50 mg/kg BDE-47 (966 genes up-regulated and 620 genes down-regulated) and in YY-9 exposed to 10 mg/kg BDE-47 (85 genes up-regulated and 291 genes down-regulated), in good accordance with the observed metabolic alternation in the two cultivars. Analyses of metabolic pathways and KEGG enrichment revealed that many biological processes, including energy consumption and biosynthesis, were perturbed in the two rice cultivars by BDE-47. A majority of metabolites and genes involved in dominating pathways of energy consumption (e.g., tricarboxylic acid cycle) and the biosynthesis (e.g., metabolism of saccharides and amino acids) were enhanced in LJ-7 by BDE-47. In contrast, energy consumption was increased while biosynthetic processes were inhibited in YY-9 by BDE-47, which could lead to the sensitivity of YY-9 to BDE-47. The combined results suggest that the different defensive abilities of these two rice cultivars in response to BDE-47 could be attributed to their differences in energy-consumption strategy and biosynthesis of nutritional components in grains. This study provides a useful reference for rice cultivation in PBDE-polluted areas.

19.
Langmuir ; 35(40): 12914-12926, 2019 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-31525935

RESUMO

Tea leaves have been explored as an economically viable and environmentally friendly source of biomass carbon. Tea leaf porous carbon (TPC) with a three-dimensional (3D) structure was prepared by a potassium hydroxide pretreatment and high-temperature calcination method, and the preparation process was simple and self-templating. The prepared TPC has a large specific surface area (1620.05 m2 g-1), three-dimensional multilayer pore structure, uniform pore size, and high oxygen content (15.51%). Both the calcination temperature and the activation level have an effect on the structure and performance of the TPC. The TPC electrode can generate a large amount of hydrogen peroxide in the initial stage of the degradation process, thereby increasing the amount of hydroxyl radicals generated and removing organic pollutants. Therefore, phenol was used to test the degradation effects and evaluate the degradation performance of TPC. Under suitable degradation conditions, TPC-800-2 showed a 95.41% degradation rate after 120 min of degradation, which is superior to that of other calcination temperatures and activation levels. The removal efficiency of chemical oxygen demand after 180 min was 90.0% and showed good stability after being used 20 times. Our work illustrates that a simple, high-performance self-templating synthetic strategy for producing novel 3D-TPC from biomass sources can play a significant role in the actual wastewater treatment of other biomass materials.

20.
Exp Cell Res ; 384(1): 111618, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31505167

RESUMO

End binding protein 1 (EB1) is a key regulator of microtubule dynamics that orchestrates hierarchical interaction networks at microtubule plus ends to control proper cell division. EB1 activity is known to be regulated by serine/threonine phosphorylation; however, how tyrosine phosphorylation affects EB1 activity remains poorly understood. In this study, we mapped the tyrosine phosphorylation pattern of EB1 in synchronized cells and identified two tyrosine phosphorylation sites (Y217 and Y247) in mitotic cells. Using phospho-deficient (Y/F) and phospho-mimic (Y/D) mutants, we revealed that Y247, but not Y217, is critical for astral microtubule stability. The Y247D mutant contributed to increased spindle angle, indicative of defects in spindle orientation. Time-lapse microscopy revealed that the Y247D mutant significantly delayed mitotic progression by increasing the duration times of prometaphase and metaphase. Structural analysis suggests that Y247 mutants lead to instability of the hydrophobic cavity in the EB homology (EBH) domain, thereby affecting its interactions with p150glued, a protein essential for Gαi/LGN/NuMA complex capture. These findings uncover a crucial role for EB1 phosphorylation in the regulation of mitotic spindle orientation and cell division.

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