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1.
Front Pediatr ; 12: 1342514, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38560399

RESUMO

Background: Short sleep duration has been related to obesity in children and adolescents. However, it remains unknown whether late bedtime is also associated with obesity and whether the association is independent of sleep duration. A meta-analysis was performed to address this issue. Methods: In order to accomplish the aim of the meta-analysis, a comprehensive search was conducted on databases including PubMed, Embase, and Web of Science to identify observational studies. The cutoff to determine late bedtime in children in this meta-analysis was consistent with the value used among the included original studies. As for obesity, it was typically defined as a body mass index (BMI) > 95th percentile of age and sex specified reference standards or the International Obesity Task Force defined age- and gender-specific cut-off of BMI. The Cochrane Q test was employed to evaluate heterogeneity among the included studies, while the I2 statistic was estimated. Random-effects models were utilized to merge the results, considering the potential impact of heterogeneity. Results: Tweleve observational studies with 57,728 participants were included. Among them, 6,815 (11.8%) were obese. Pooled results showed that late bedtime reported by the participants or their caregivers was associated with obesity (odds ratio [OR]: 1.27, 95% confidence interval [CI]: 1.16-1.39, p < 0.001; I2 = 0%). Subgroup analysis showed consistent results in studies with (OR: 1.33, 95% CI: 1.04-1.70, p = 0.02) and without adjustment of sleep duration (OR: 1.27, 95% CI: 1.14-1.41, p < 0.001). Further subgroup analysis also showed that the association was not significantly affected by study location, design, age of the participants, or diagnostic methods for obesity (p for subgroup difference all >0.05). Conclusion: Late bedtime is associated with obesity in children and adolescents, which may be independent of sleep duration.

2.
Medicine (Baltimore) ; 102(32): e34599, 2023 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-37565892

RESUMO

Patients undergoing allogeneic hematopoietic stem cell transplantation (HSCT) are at an increased risk of developing severe acute respiratory distress syndrome (ARDS), which is characterized by peripheral bilateral patchy lung involvement. The regulatory network of RNA-binding protein (RBP)-alternative splicing (AS) in ARDS following HSCT has not been investigated. We hypothesize that RBP-AS plays a regulatory role during HSCT-ARDS. The published ARDS transcriptome data after HSCT (GSE84439) were downloaded, and the transcriptome data of 13 mRNAs were obtained by sequencing the peripheral blood of 5 HSCT-ARDS patients and 8 ARDS patients through high-throughput sequencing technology. Systematic analysis of downloaded data was performed to obtain differentially expressed RBPs, and the differentially alternative spliced pre-mRNAs in HSCT-ARDS and control groups were used to explore the global gene RBP-AS regulatory network. A total of 1769 differentially expressed genes and 4714 regulated alternative splicing events were identified in peripheral blood from HSCT-ARDS, of which 254 genes had both differential expression and differential AS. In addition, 128 RBPs were identified, of which HDGF, PCBP2, RIOK3, CISD2, and TRIM21, DDX58, MOV10 showed significantly increased or decreased expression in the HSCT-ARDS. RBPs with decreased expression had antiviral activity, while those with increased expression were involved in ROS, fibrosis, and negative viral resistance. The RBP-RASE-RASG regulatory network is constructed. It is related to the dysregulation of antiviral immunomodulation, imbalance in ROS homeostasis and pro-pulmonary fibrosis, which are involved in the development of HSCT-ARDS.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Síndrome do Desconforto Respiratório , Humanos , Processamento Alternativo/genética , Espécies Reativas de Oxigênio/metabolismo , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Síndrome do Desconforto Respiratório/genética , Síndrome do Desconforto Respiratório/terapia , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Antivirais
3.
Materials (Basel) ; 15(6)2022 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-35329530

RESUMO

The microstructure and mechanical properties of Ti(C,N)-based cermets with the addition of the SiC particles (SiCp) and SiC whiskers (SiCw), were systematically studied in this work. Firstly, the effect of SiCp on the cermets was investigated independently to determine the considerable total amounts of additives, and the results showed that 2.0 wt.% SiCp would lead to optimal properties of the cermet. Then, the influence of SiCp and SiCw additions with the variable ratio on the cermets was studied. The results indicated that when 1.5 wt.% SiCp and 0.5 wt.% SiCw were added; the cermets appeared with the best comprehensive properties, and the transverse rupture strength, hardness, and the fracture toughness of the cermets reached 2520.8 MPa, 88.0 HRA, and 16.56 MPa·m1/2, respectively. This was due to the synergistic strengthening and toughening effect afforded by the reasonable SiCp and SiCw addition, from which the smallest grain size, as well as the most uniform, and completed core-rim structure of the cermets, were achieved.

4.
J Hazard Mater ; 406: 124327, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33139106

RESUMO

This work presents a systematical experimental and density functional theory (DFT) studies to reveal the mechanism of NO reduction by H2 reaction over platinum nanoparticles (NPs) deposited on boron-doped graphene (denoted as Pt/BG) catalyst. Both characterizations and DFT calculations identified boron (in Pt/BG) as an additional NO adsorption site other than the widely recognized Pt NPs. Moreover, BG led to a decrease of Pt NPs size in Pt/BG, which facilitated hydrogen spillover. The mathematical and physical criteria of the Langmuir-Hinshelwood dual-site kinetic model over the Pt/BG were satisfied, indicating that adsorbed NO on boron (in Pt/BG) was further activated by H-spillover. On the other hand, Pt/graphene (Pt/Gr) demonstrated a typical Langmuir-Hinshelwood single-site mechanism where Pt NPs solely served as active sites for NO adsorption. This work helps understand NO-H2 reaction over Pt/BG and Pt/Gr catalysts in a closely mechanistic view and provides new insights into roles of active sites for improving the design of catalysts for NO abatement.

5.
Nanoscale ; 10(21): 10203-10212, 2018 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-29786726

RESUMO

A series of boron-doped graphene-supported Pt (Pt/BG) nanosheets were designed and synthesized using a one-step facile hydrothermal method. ICP, XPS, and TPD results confirmed that boron atoms were successfully embedded into the graphene matrix. The selective catalytic reduction of nitric oxide with hydrogen (H2-SCR) was tested over Pt/BG catalysts. The multi-roles of doped-boron were investigated by Raman, BET, CO-chemisorption, H2-TPD, XPS, and NO-TPD. Boron doping led to a higher dispersion and smaller size of Pt nanoparticles, facilitated hydrogen spillover, promoted more metallic Pt formation, and increased both H2 and NO chemisorption, which were attributed to an enhanced Pt nucleation rate over doped-boron, electron donation from boron to Pt, and extra chemisorption sites. The reaction performances (conversion 94.7%, selectivity 90.3%, and TOF 0.092 s-1) were greatly promoted attributing to a bifunctional catalytic mechanism. This work paves the way to modify the structure and tune the chemisorption ability of graphene-based catalysts, and provides novel insights for designing high performance catalysts.

6.
Nat Commun ; 8(1): 930, 2017 10 13.
Artigo em Inglês | MEDLINE | ID: mdl-29030605

RESUMO

The long-sought cubic gauche phase of polymeric nitrogen (cg-PN) with nitrogen-nitrogen single bonds has been synthesized together with a related phase by a radio-frequency plasma reaction under near-ambient conditions. Here, we report the synthesis of polymeric nitrogen using a mixture of nitrogen and argon flowing over bulk ß-sodium azide or ß-sodium azide dispersed on 100 nm long multiwall carbon nanotubes. The cg-PN phase is identified by Raman and attenuated total reflection-Fourier transform infrared spectroscopy, and powder X-ray diffraction. The synthesis of the cubic gauche allotrope of high energy density polymeric nitrogen under near-ambient conditions should therefore enable its optimized production and applications as a "green" energetic material and a potential catalyst for different chemical reactions.Polymeric phases of nitrogen are promising as environmentally-friendly, high energy-density materials, but are inherently unstable. Here, the authors report the synthesis and stabilization of polymeric nitrogen in its cubic gauche phase under near-ambient conditions, via plasma-enhanced chemical vapour deposition.

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