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1.
J Nanosci Nanotechnol ; 20(2): 909-917, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31383086

RESUMO

Tailored broussonetia-like NiCo2O4 is grown on carbon cloth using tri-sodium citrate assisted hydrothermal method. The chelating effect of citric ions has been utilized to investigate the morphological and structural evolution of NiCo2O4 on carbon cloth, which have been illustrated by scanning electron microscopy, transmission electron microscopy, and X-ray photoelectron spectra. The results demonstrate that the morphological alteration of NiCo2O4 from single nanowire to broussonetia-like structure has been detected after the addition of tri-sodium citrate. Citric ion plays a crucial role as an electrostatic stabilizer in determining this unique structure. When used as binder-free electrode in aqueous supercapacitors, the broussonetia-like NiCo2O4 electrode exhibits a specific capacitance of 527.9 F g-1 at a current density of 0.5 A g-1. Additionally, an asymmetric supercapacitor is further assembled using NiCo2O4 as the positive electrode and activated carbon as negative electrode. The device exhibits a maximum energy of 26.4 Wh kg-1 at power density of 800 W kg-1. A long-term cycling stability with 82% capacitance retention is maintained after 20,000 cycles at a current density of 5 A g-1, indicating the practical applicability of the tested device.

3.
Aging (Albany NY) ; 112019 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-31477637

RESUMO

OBJECTIVES: Autophagy is an evolutionarily conserved intracellular degradation mechanism in which cell constituents are phagocytosed to maintain cellular homeostasis. Forkhead box O 3a (FoxO3a) promotes autophagy to protect cells from environmental stress. Methylated CpG binding protein 2 (MeCP2) is a nuclear protein that binds DNA and represses transcription. However, the mechanism and interplay between FoxO3a and MeCP2 underlying endothelial progenitor cell (EPC) function are not fully understood. RESULTS: In EPCs, MeCP2 overexpression attenuated autophagy and cell functionality, which were reversed by the autophagy activator rapamycin or co-transfection with FoxO3a. FoxO3a promoted cell function, which was reversed by the autophagy inhibitor chloroquine. Following MeCP2 overexpression, MeCP2 was found enriched on the FoxO3a promoter, resulting in promoter hypermethylation and enhanced H3K9 histone modification in nucleosomes of the FoxO3a promoter. CONCLUSIONS: MeCP2 attenuated cell functionality via DNA hypermethylation and histone modification of the FoxO3a promoter to inhibit FoxO3a transcription and autophagy. MATERIALS AND METHODS: EPCs were isolated from human umbilical cord blood and treated with adenoviral vectors containing interference sequences. The effects and mechanism of MeCP2 and FoxO3a were analyzed by utilizing western blotting, cell counting kit-8, transwell plates, Matrigel, matrix adhesion, transmission electron microscopy, and chromatin immunoprecipitation.

5.
Soft Matter ; 2019 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-31475722

RESUMO

Correction for 'Implicit-solvent coarse-grained modeling for polymer solutions via Mori-Zwanzig formalism' by Shu Wang et al., Soft Matter, 2019, DOI: 10.1039/c9sm01211g.

6.
Magn Reson Imaging ; 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31484043

RESUMO

PURPOSE: To investigate the utility of diffusion kurtosis imaging (DKI) MRI for evaluation of renal fibrosis in rats with unilateral ureteral obstruction (UUO). METHODS: Twenty-five rats had UUO, and ten rats were subjected to sham operation as control. DKI was performed on a 3.0 T MRI scanner on days 1, 3, 5, and 7 after ligation. All rats then underwent 18F-FDG dynamic PET to evaluate unilateral renal function, followed by histological analysis to examine α-smooth muscle actin (α-SMA) expression. DKI metrics were assessed among the time points and between two sides, and compared with maximum standardized uptake value (SUVmax), serum levels of creatinine and urea, and fibrosis marker α-SMA. RESULTS: Mean kurtosis (MK) on day 7, axial kurtosis (Ka) on days 3 and 7, mean diffusivity (MD) on days 1, 3, 5, and 7, and fractional anisotropy (FA) on days 3, 5, and 7 of cortex and medulla between the UUO and contralateral sides were significantly different (all p < 0.05). Over the course of UUO progression, there were significant changes in Ka, MD and FA of medulla (all p < 0.05). FA of medulla was positively correlated with SUVmax (r = 0.641, p < 0.001), and MD of cortex was negatively correlated with urea (r = -0.534, p = 0.001). MD of cortex was negatively correlated with α-SMA on UUO sides (r = -0.710, p < 0.001). CONCLUSIONS: DKI shows the potential for noninvasive assessment of renal fibrosis and unilateral renal function induced by UUO.

7.
Hepatol Int ; 2019 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-31486964

RESUMO

BACKGROUND AND AIMS: Surgical resection for hepatocellular carcinoma (HCC) is potentially curative, but long-term survival remains unsatisfactory. There is currently no effective neoadjuvant or adjuvant therapy for HCC. We sought to evaluate the impact of preoperative transcatheter arterial chemoembolization (TACE) on long-term prognosis after surgical resection of huge HCCs (≥ 10 cm). METHODS: Using a multicenter database, consecutive patients who underwent curative-intent resection for huge HCC without macrovascular invasion between 2004 and 2014 were identified. The association between preoperative TACE with perioperative outcomes, long-term overall survival (OS), and recurrence-free survival (RFS) was assessed before and after propensity score matching (PSM). RESULTS: Among the 377 enrolled patients, 88 patients (23.3%) received preoperative TACE. The incidence of perioperative mortality and morbidity was comparable among patients who did and did not undergo preoperative TACE (3.4% vs. 2.4%, p= 0.704, and 33.0% vs. 31.1%, p= 0.749, respectively). PSM analysis created 84 matched pairs of patients. In examining the entire cohort as well as the PSM cohort, median OS (overall cohort: 32.8 vs. 22.3 months, p= 0.035, and PSM only: 32.8 vs. 18.1 months, p= 0.023, respectively) and RFS (12.9 vs. 6.4 months, p= 0.016, and 12.9 vs. 4.1 months, p= 0.009, respectively) were better among patients who underwent preoperative TACE vs. patients who did not. After adjustment for other confounding factors on multivariable analyses, preoperative TACE remained independently associated with a favorable OS and RFS after the resection of huge HCC. CONCLUSION: Preoperative TACE did not increase perioperative morbidity or mortality, yet was associated with an improved OS and RFS after liver resection of huge HCC (≥ 10 cm).

8.
Small ; : e1904216, 2019 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-31489776

RESUMO

Considerable efforts are devoted to relieve the critical lithium dendritic and volume change problems in the lithium metal anode. Constructing uniform Li+ distribution and lithium "host" are shown to be the most promising strategies to drive practical lithium metal anode development. Herein, a uniform Li nucleation/growth behavior in a confined nanospace is verified by constructing vertical graphene on a 3D commercial copper mesh. The difference of solid-electrolyte interphase (SEI) composition and lithium growth behavior in the confined nanospace is further demonstrated by in-depth X-ray photoelectron spectrometer (XPS) and line-scan energy dispersive X-ray spectroscopic (EDS) methods. As a result, a high Columbic efficiency of 97% beyond 250 cycles at a current density of 2 mA cm-2 and a prolonged lifespan of symmetrical cell (500 cycles at 5 mA cm-2 ) can be easily achieved. More meaningfully, the solid-state lithium metal cell paired with the composite lithium anode and LiNi0.5 Co0.2 Mn0.3 O2 (NCM) as the cathode also demonstrate reduced polarization and extended cycle. The present confined nanospace-derived hybrid anode can further promote the development of future all solid-state lithium metal batteries.

9.
J Cell Biochem ; 2019 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-31489990

RESUMO

The dysregulation of miR-125a-3p has been observed in multiple tumor types. Nevertheless, the function of miR-125a-3p in papillary thyroid carcinoma (PTC) is yet to be explored. Herein, we find that miR-125a-3p is markedly downregulated in PTC tissues, and its level is inversely related to the histological grade of PTC. Upregulation of miR-125a-3p suppresses the pulmonary metastatic ability as well as the tumor growth of PTC cell in vivo. Consistently, the colony formation ability and other metastasis-related traits of PTC cell are inhibited by miR-125a-3p transfection in vitro. In addition, we identify that matrix metalloprotease 11 (MMP11) is the direct target gene of miR-125a-3p, and that miR-125a-3p inhibits cell viability, migration, and invasiveness of PTC cell by reducing MMP11 expression in vitro. Together, these data testify that the miR-125a-3p/MMP11 axis plays vital roles in the growth and progression of human PTC cells.

10.
BMC Infect Dis ; 19(1): 771, 2019 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-31481053

RESUMO

BACKGROUND: Although worldwide measles elimination achieved great progress for decades, outbreaks were still reported in certain countries. This study describes the epidemiologic features of a substantial measles outbreak in an office building in Beijing and explores control strategies in a crowded city. METHODS: We performed descriptive analyses of data on demographic characteristic, laboratory testing and epidemiological information. RESULTS: From February 25 to March 28, 2016, 43 outbreak-related measles cases occurred in an office building in Beijing. The total crude attack rate was 1.20% in the building. The age range of patients was 23 to 45 years old, of whom 30 (69.8%) were migrants and 5 (11.6%) were vaccinated but without documentation. The attack rate of the department and the company of the source case was 22.73 and 11.86%, respectively. The attack rate in the building was 1.78%, except for the commercial center on the lower floors, which was 0.34%. Of the 43 measles cases, only 19 cases (53.5%) were reported by hospitals through the National Notifiable Disease Reporting System (NNDRS), and the rest were found through active surveillance. Outbreak response immunization was conducted for 6216 persons. CONCLUSIONS: Office buildings in crowded metropolis are prone to large-scale measles outbreaks, and require a rapid outbreak response. Early Outbreak response immunization and active surveillance are important strategies to control outbreaks such as the one reported herein.

11.
J Clin Invest ; 2019 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-31483291

RESUMO

Electronic nicotine delivery systems (ENDS) or e-cigarettes have emerged as a popular recreational tool among adolescents and adults. Although the use of ENDS is often promoted as a safer alternative to conventional cigarettes, few comprehensive studies have assessed the long-term effects of vaporized nicotine and its associated solvents, propylene glycol (PG) and vegetable glycerin (VG). Here, we show that compared with smoke exposure, mice receiving ENDS vapor for 4 months failed to develop pulmonary inflammation or emphysema. However, ENDS exposure, independent of nicotine, altered lung lipid homeostasis in alveolar macrophages and epithelial cells. Comprehensive lipidomic and structural analyses of the lungs revealed aberrant phospholipids in alveolar macrophages and increased surfactant-associated phospholipids in the airway. In addition to ENDS-induced lipid deposition, chronic ENDS vapor exposure downregulated innate immunity against viral pathogens in resident macrophages. Moreover, independent of nicotine, ENDS-exposed mice infected with influenza demonstrated enhanced lung inflammation and tissue damage. Together, our findings reveal that chronic e-cigarette vapor aberrantly alters the physiology of lung epithelial cells and resident immune cells and promotes poor response to infectious challenge. Notably, alterations in lipid homeostasis and immune impairment are independent of nicotine, thereby warranting more extensive investigations of the vehicle solvents used in e-cigarettes.

12.
World J Gastroenterol ; 25(27): 3619-3633, 2019 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-31367161

RESUMO

BACKGROUND: Magnetic resonance enterography (MRE) is increasingly attractive as a noninvasive and radiation-free tool for assessing Crohn's disease (CD). Diffusion-weighted imaging (DWI) is recommended as an optional MRE sequence for CD by the European Society of Gastrointestinal and Abdominal Radiology, and has shown a superb potential as a quantitative modality for bowel inflammation evaluation. However, the measurement reproducibility of quantitative DWI analysis in MRE has not been ascertained so far. To facilitate the application of quantitative diffusion-weighted MRE in the clinical routine, systematic investigations of the intra and interobserver reproducibility of DWI quantitative parameters should be performed. AIM: To evaluate the intra and interobserver reproducibility of quantitative analysis for diffusion-weighted MRE (DW-MRE) in ileal CD. METHODS: Forty-four subjects (21 with CD and 23 control subjects) who underwent ileocolonoscopy and DW-MRE (b = 800 s/mm2) within one week were included. Two radiologists independently measured apparent diffusion coefficients (ADC) of the terminal ileum and signal intensity ratio (SR) of the terminal ileum to ipsilateral psoas muscle on DWI images (b = 800 s/mm2). Between- and within-reader agreements were assessed using intraclass correlation coefficients (ICC), coefficients of variation (CoV), and 95% limits of agreement of Bland-Altman plots (BA-LA LoA). Diagnostic performances of ADC and SR for identifying inflamed terminal ileum from the normal were evaluated by receiver operating characteristic (ROC) curve analysis. RESULTS: There were no significant differences in ADC or SR values between the two sessions or between the two radiologists either in the CD or control group (paired t-test, P > 0.05). The intra and interobserver reproducibility of ADC (ICC: 0.952-0.984; CoV: 3.73-6.28%; BA-LA LoA: ±11.27% to ±15.88%) and SR (ICC: 0.969-0.989; CoV: 3.51%-4.64%; BA-LA LoA: ±10.62% to ±15.45%) was excellent for CD. Agreement of ADC measurements was slightly less in control subjects (ICC: 0.641-0.736; CoV: 10.47%-11.43%; BA-LA LoA: ± 26.59% to ± 30.83%). SR of normal terminal ileum demonstrated high intra and interobserver reproducibility (ICC: 0.944-0.974; CoV: 3.73%-6.28%; BA-LA LoA: ± 18.58% to ± 24.43%). ADC and SR of two readers had outstanding diagnostic efficiencies (area under the ROC curve: 0.923-0.988). CONCLUSION: Quantitative parameters derived from DW-MRE have good to excellent intra and interobserver agreements with high diagnostic accuracy, and can serve as robust and efficient quantitative biomarkers for CD evaluation.

13.
Artigo em Inglês | MEDLINE | ID: mdl-31369289

RESUMO

In recent studies, microRNAs (miRs) have been widely explored as important regulator in tumor suppression. MiR-136 has been suggested to participate in tumor inhibition through control of vital cellular processes, such as angiogenesis, proliferation and apoptosis. This study aimed to evaluate the effects of overexpressed miR-136 by transferring mimics in gallbladder cancer (GBC) and to assess the functional role of miR-136 in GBC cell behaviors with the involvement of the MAP2K4-dependent JNK signaling pathway. Differentially expressed miRs associated with GBC were screened using microarray expression profiles, which identified that miR-136 expression was decreased in GBC. Furthermore, MAP2K4 was validated as a target gene of miR-136. In order to uncover functional relevance regarding miR-136 and MAP2K4 in GBC, cultured GBC cell lines were prepared to transfect with mimic, inhibitor, siRNA or vectors. At the same time, the transfected GBC cells were inoculated into nude mice to validate findings in vivo. The obtained results demonstrated that overexpressed miR-136 inhibited angiogenesis, cell proliferation and promoted apoptosis in GBC cell lines in vitro, accompanied by impeded cellular tumorigenicity in nude mice via the suppression of MAP2K4. Moreover, the overexpression of MAP2K4 and the activation of the JNK signaling pathway reversed the inhibitory effects of miR-136 on the angiogenesis and tumorigenicity of GBC cells. Together, our results indicated that overexpressed miR-136 attenuates angiogenesis and enhances cell apoptosis in GBC via the JNK signaling pathway by down-regulating the expression of MAP2K4.

14.
Opt Lett ; 44(15): 3705-3708, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31368948

RESUMO

In this Letter, the frequency expansion of an orthogonally polarized dual-wavelength laser, based on the cascaded stimulated Raman scattering, was demonstrated for the first time, to the best of our knowledge. The dual-wavelength fundamental laser generated from two separate Nd:YLF crystals was free of gain competition. Integrating the benefit of the two different orthogonally polarized Raman gain peaks in the KGd(WO4)2 (KGW) crystal, two sets of first-Stokes orthogonally polarized dual-wavelength Raman lasers were first achieved by rotating the Raman crystal for 90°. Furthermore, by simply replacing the Raman output coupler, we attained another two sets of second-Stokes orthogonally polarized dual-wavelength Raman lasers via the cascaded Raman shift. At a pulse repetition frequency of 5 kHz, the maximum first-Stokes and second-Stokes dual-wavelength Raman output powers were 3.12 and 2.09 W, with the combined peak powers of approximately 240 and 290 kW, respectively.

15.
J Chem Inf Model ; 2019 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-31438677

RESUMO

Accurate prediction of molecular properties is important for new compound design, which is a crucial step in drug discovery. In this paper, molecular graph data is utilized for property prediction based on graph convolution neural networks. In addition, a convolution spatial graph embedding layer (C-SGEL) is introduced to retain the spatial connection information on molecules. And, multiple C-SGELs are stacked to construct a convolution spatial graph embedding network (C-SGEN) for end-to-end representation learning. In order to enhance the robustness of the network, molecular fingerprints are also combined with C-SGEN to build a composite model for predicting molecular properties. Our comparative experiments have shown that our method is accurate and achieves the best results on some open benchmark datasets.

16.
J Microbiol ; 2019 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-31463790

RESUMO

rRNA gene high-throughput sequencing was performed in the conjunctival swab samples to investigate the composition of the OS bacterial community in DE (n=35) and NDE (n=54) and compared the composition of MGD (n=25) and NMGD (n=10) among DE subjects. Deep sequencing of OS 16S rDNA from DE (n=35) and NDE (n=54) demonstrated great a difference in alpha and beta diversity between the OS bacterial flora (P < 0.05). The similar OS microbial structures were shown at the phylum and genus levels by bioinformatics analysis between them, and in LEfSe (linear discriminant analysis effect size) analysis, Bacteroidia and Bacteroidetes were enriched in DE, while Pseudomonas was plentiful in NDE (linear discriminant analysis [LDA] > 4.0). Among the DE group, there was no significant difference in α and ß diversity between MGD and NMGD (P > 0.05). Surprisingly, Bacilli was the dominant microbe in MGD, and Bacteroidetes was the superior bacteria in NMGD among DE subjects (LDA > 4.0). Different diversity of OS bacteria composition between DE and NDE and the altered diversity of OS bacteria may play an important role in DE. Moreover, the lower dominance of OS bacteria in DE may be associated with the occurrence and development of DE. Although there was no significant difference in alpha and beta analysis, the OS dominant microbe between MGD and NMGD among DE was different.

17.
Cell Death Dis ; 10(9): 629, 2019 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-31427569

RESUMO

There is growing evidence that the long non-coding RNAs(lncRNAs) play an important role in the biological behaviors of glioblastoma cells. In this study, we elucidated the function and possible effect and molecular mechanisms of lncRNA-Linc-00313 on the biological behaviors of glioblastoma cells as well as UPF1 function as a RNA-binding protein to enhance its stability. Here, we used qRT-PCR and western blot to measure the expression, cell Transfection to disrupt the expression of genes, cell viability analysis, quantization of apoptosis, cell migration, and invasion assays, Reporter vectors construction and luciferase assays to investigate the malignant biological behaviors of cells, human lncRNA microarrays, RNA-Immunoprecipitation, dual-luciferase gene reporter assay, half-life assay and chromatin immunoprecipitation to verify the binding sites, tumor xenograft implantation for in vivo experiment, SPSS 18.0 statistical software for data statistics. UPF1 and Linc-00313 were both upregulated in glioma tissues and cells. Knockdown of UPF1 or Linc-00313 significantly inhibited malignant biological behaviors of glioma cells by regulating miR-342-3p and miR-485-5p, which are downregulated and functioned as tumor suppressors in glioma. Furthermore, Linc-00313 could acted as a competing endogenous RNA(ceRNA) to regulate the expression of Zic4 by binding to miR-342-3p and miR-485-5p. Interestingly, Zic4 could bind to the promoters of UPF1 and Linc-00313 respectively and upregulate the expression of them. These results indicated that a positive-feedback loop was formed in the regulation of the biological behaviors of glioma cells. The study is the first to prove that the UPF1-Linc-00313-miR-342-3p/miR-485-5p-Zic4-SHCBP1 pathway forms a positive-feedback loop and regulates the biological behaviors of U87 and U251 cells, which might provide a new therapeutic target for glioma.

18.
Cell Death Dis ; 10(9): 632, 2019 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-31434870

RESUMO

Following the publication of this article, the authors realized there was an error in Figure 6H in which two versions of the figure appear.This does not impact the conclusions of the article.

19.
Int J Mol Sci ; 20(17)2019 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-31438494

RESUMO

Human variants in plakophilin-2 (PKP2) associate with most cases of familial arrhythmogenic cardiomyopathy (ACM). Recent studies show that PKP2 not only maintains intercellular coupling, but also regulates transcription of genes involved in Ca2+ cycling and cardiac rhythm. ACM penetrance is low and it remains uncertain, which genetic and environmental modifiers are crucial for developing the cardiomyopathy. In this study, heterozygous PKP2 knock-out mice (PKP2-Hz) were used to investigate the influence of exercise, pressure overload, and inflammation on a PKP2-related disease progression. In PKP2-Hz mice, protein levels of Ca2+-handling proteins were reduced compared to wildtype (WT). PKP2-Hz hearts exposed to voluntary exercise training showed right ventricular lateral connexin43 expression, right ventricular conduction slowing, and a higher susceptibility towards arrhythmias. Pressure overload increased levels of fibrosis in PKP2-Hz hearts, without affecting the susceptibility towards arrhythmias. Experimental autoimmune myocarditis caused more severe subepicardial fibrosis, cell death, and inflammatory infiltrates in PKP2-Hz hearts than in WT. To conclude, PKP2 haploinsufficiency in the murine heart modulates the cardiac response to environmental modifiers via different mechanisms. Exercise upon PKP2 deficiency induces a pro-arrhythmic cardiac remodeling, likely based on impaired Ca2+ cycling and electrical conduction, versus structural remodeling. Pathophysiological stimuli mainly exaggerate the fibrotic and inflammatory response.

20.
Artigo em Inglês | MEDLINE | ID: mdl-31438638

RESUMO

Tai Chi Chuan (TCC) as a typical mind-body practice has been investigated for its preventive role on negative emotions and has demonstrated its efficacy in healthy populations. However, the results are not consistent. We performed a meta-analysis and systematically evaluated the effect of TCC on selected negative emotions (i.e., anxiety and depression). Fourteen experimental studies from three English-and two Chinese-language databases were evaluated. The results showed that the positive effects of TCC on negative emotions were moderately to largely significant. In addition, although TCC significantly improved negative emotions in both the young adults and the older adults, old adults benefited more from TCC than young adults. These findings suggest that TCC is a worthy complementary non-pharmacological resource towards depression and anxiety and, thus, has great implications for the public health domain.

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