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1.
Nanotechnology ; 31(2): 025402, 2020 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-31530741

RESUMO

Flexible, heteroatoms-rich activated carbon nanofibers with fascinating cross-linked architectures are successfully gained in a facile and controllable way via electrospinning polyacrylonitrile (PAN) /dicyandiamide (DICY) composite nanofibers followed by carbonation and a CO2 activation process. The unique inter-bonded structures and heteroatoms contents could be easily controlled by adjusting the preoxidation temperature applied in the calcining procedure and the addition of DICY. Significantly, the resultant samples display hierarchical pores with micro/meso/macropores, abundant N, O species doped and unique fiber-fiber interconnections, which considerably boost the electrochemical properties. As an electrode material, the activated N-doped cross-linked carbon nanofibers (ANCLCNFs) show a high capacitance of 323 F g-1 with a current density of 0.5 A g-1, excellent rate capacity (230.1 F g-1 at 20 A g-1) and long-term duration (over 95% after 10000 cycles). Furthermore, the symmetrical supercapacitor delivers a maximum energy density of 14.3 Wh kg-1 at a power density of 162.5 W kg-1.

2.
Endocr Relat Cancer ; 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31693489

RESUMO

Papillary thyroid carcinoma (PTC) is one of the most prevalent tumors in endocrine system. CircRNAs (circular RNAs) are widely known as critical regulators in tumorigenesis of papillary thyroid carcinoma (PTC). The present study focused on the functional investigation and potential molecular mechanism toward circ_0005273 in PTC progression. Gene Expression Omnibus datasets (GSE93522) and qRT-PCR (quantitative real-time polymerase chain reaction) analyses showed that circ_0005273 were up-regulated in PTC tissues and cell lines. Moreover, circ_0005273 was located in the cytoplasm of PTC cells, and suggested poor prognosis in PTC patients. In vivo and in vitro functional assays indicated that knockdown of circ_0005273 inhibited PTC tumor growth and progression, respectively. Mechanistically, miR-1183 was identified as functional target of circ_0005273, and circ_0005273 could directly bind to miR-1138 and relieve inhibition of SRY (sex determining region Y)-box 2 (SOX2). Data from Cell Counting Kit-8, colony formation assays and transwell assays revealed that the oncogenic role of circ_0005273 on PTC progression dependent on miR-1183-mediated SOX2 expression. In conclusion, circ_0005273 functioned as a tumor promoter of PTC via circ_0005273/miR-1183/SOX2 axis, suggesting a novel biomarker and therapeutic target for PTC.

3.
Small ; : e1903379, 2019 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-31553139

RESUMO

The current understanding of motility through body shape deformation of micro-organisms and the knowledge of fluid flows at the microscale provides ample examples for mimicry and design of soft microrobots. In this work, a 2D spiral is presented that is capable of rotating by non-reciprocal curling deformations. The body of the microswimmer is a ribbon consisting of a thermoresponsive hydrogel bilayer with embedded plasmonic gold nanorods. Such a system allows fast local photothermal heating and nonreciprocal bending deformation of the hydrogel bilayer under nonequilibrium conditions. It is shown that the spiral acts as a spring capable of large deformations thanks to its low stiffness, which is tunable by the swelling degree of the hydrogel and the temperature. Tethering the ribbon to a freely rotating microsphere enables rotational motion of the spiral by stroboscopic irradiation. The efficiency of the rotor is estimated using resistive force theory for Stokes flow. This research demonstrates microscopic locomotion by the shape change of a spiral and may find applications in the field of microfluidics, or soft microrobotics.

4.
Ultrason Sonochem ; 59: 104714, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31479889

RESUMO

Metal-organic frameworks (MOFs) and their derivatives are excellent candidates for electrocatalysts profiting from their unique structures and accessible active sites. Generally, due to the weak poor conductivity and catalytic activity when used as OER electrocatalysts, MOFs are more likely to be used as precursors to obtain composite catalysts through further pyrolysis treatment, rather than directly applied as OER electrocatalysts. But heat treatment usually results in structural collapse and loss of active sites. Specially, as a kind of two-dimensional (2D) materials with rapid electron transfer, metal-organic framework nanosheets (MONs) have great application potential in various fields, especially in the field of catalysis, due to the advantages of both MOFs and 2D materials. Here, we have reported a simple top-down approach to synthesize Co-MONs which can be directly adopted as efficient OER catalysts. Ultrasonic bath (40 KHz, 100 W) was employed to control the exposing of the preponderant lattice plane, which can offer plentiful active catalytic sites and accelerate ions transport. The optimized Co-MONs attain 10 mA cm-2 at an overpotential of 309 mV with a small Tafel slope of 75.71 mV dec-1.

5.
Hum Mutat ; 2019 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-31489982

RESUMO

Glucose-6-phosphate dehydrogenase (G6PD) deficiency is one of the most common X-linked enzymopathies caused by G6PD gene variant. We aimed to provide the characteristics of G6PD deficiency and G6PD gene variant distribution in a large Chinese newborn screening population. We investigated the prevalence of G6PD in China from 2013 to 2017. Then, we examined G6PD activity and G6PD gene in representative Chinese birth cohort to explore the distribution of G6PD gene variant in 2016. We then performed multicolor melting curve analysis to classify G6PD gene variants in 10,357 neonates with activity-confirmed G6PD deficiency, and DNA Sanger sequencing for G6PD coding exons if hot site variants were not found. The screened population, organizations, and provinces of G6PD deficiency were increased from 2013 to 2017 in China. The top five frequency of G6PD gene variants were c.1376G>T, c.1388G>A, c.95A>G, c.1024C>T, and c.871G>A and varied in different provinces, with regional and ethnic features, and four pathogenic variant sites (c.152C>T, c.290A>T, c.697G>C, and c.1285A>G) were first reported. G6PD deficiency mainly occurs in South China, and the frequency of G6PD gene variant varies in different regions and ethnicities.

6.
Nat Commun ; 10(1): 4027, 2019 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-31492837

RESUMO

Cells feel the forces exerted on them by the surrounding extracellular matrix (ECM) environment and respond to them. While many cell fate processes are dictated by these forces, which are highly synchronized in space and time, abnormal force transduction is implicated in the progression of many diseases (muscular dystrophy, cancer). However, material platforms that enable transient, cyclic forces in vitro to recreate an in vivo-like scenario remain a challenge. Here, we report a hydrogel system that rapidly beats (actuates) with spatio-temporal control using a near infra-red light trigger. Small, user-defined mechanical forces (~nN) are exerted on cells growing on the hydrogel surface at frequencies up to 10 Hz, revealing insights into the effect of actuation on cell migration and the kinetics of reversible nuclear translocation of the mechanosensor protein myocardin related transcription factor A, depending on the actuation amplitude, duration and frequency.

7.
Nanoscale ; 11(37): 17384-17395, 2019 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-31524914

RESUMO

The development of efficient and abundant transition metal bifunctional electrocatalysts is crucial in sustainable energy utilization. Copper-cobalt bimetallic composites exhibit excellent electrochemical performance but the agglomeration of nanoparticles and phase separation cannot be avoided in high temperature pyrolysis. Herein, Cu(ii) ions are introduced into Co-based zeolitic imidazolate frameworks (ZIF-67) by a polymer-coating method to synthesize copper-cobalt bimetallic composite phosphides (CuCoP). After further pyrolysis and phosphidation, the uniform CuCoP nanoparticles are embedded into N-doped carbon frameworks (CuCoP-NC) derived from organic ligands. CuCoP-NC possesses unique hollow structure, rich pores in the carbon framework and large specific surface areas. At an optimal carbonization temperature of 700 °C, CuCoP-NC-700 exhibits admirable electrocatalytic performance such as high onset potentials (0.978 V vs. reversible hydrogen potential (RHE) in alkaline media and 0.801 V vs. RHE in acidic media), large limiting current densities, long-term stability and eximious resistance to methanol poisoning towards the oxygen reduction reaction (ORR) in both alkaline and acidic media and a low overpotential of 337 mV at 10 mA cm-2 towards the oxygen evolution reaction (OER). Moreover, CuCoP-NC-700 is assembled into a Zn-air battery and presents a higher power density (116.5 mW cm-2) and stability compared to Pt/C.

8.
Curr Cardiol Rep ; 21(10): 124, 2019 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-31486924

RESUMO

PURPOSE OF REVIEW: Sympathetic overactivity plays an important role in the progression of pulmonary arterial hypertension (PAH). The purpose of this review is to illustrate localization of pulmonary arterial sympathetic nerves, the key steps of pulmonary artery denervation (PADN) procedure, and to highlight clinical outcomes. RECENT FINDINGS: Sympathetic nerves mostly occurred in the posterior region of the bifurcation and pulmonary trunk. Emerging preclinical data provided the potential of PADN for PAH. PADN, produced at bifurcation area, improved a profound reduction of pulmonary arterial pressure and ameliorated clinical outcomes with an exclusive ablation catheter. The application of PADN in the patients of PAH or combined pre-capillary and post-capillary PH (CpcPH) improved the hemodynamic parameters and increased 6MWD. Sympathetic overactivity aggravates PAH. PADN is a promising interventional treatment for PAH and CpcPH. Additional clinical trials are warranted to confirm the efficacy of PADN.

9.
iScience ; 19: 224-231, 2019 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-31377667

RESUMO

Despite the success for targeted delivery in the body, the efficient release without side effects caused by residual drug remains a challenge. For reducing residual drug, the pH-responsive carriers were prepared by self-assembly from aromatic macrocycles, which were non-toxic and biocompatible. The inner surroundings of aromatic macrocycles could be protonated positively by acid inducing the separation of neighboring macrocycles. Thus, Dox-loaded carriers successfully inhibited the proliferation of carcinoma cells (HepG2 and 4T1) rather than normal cells (HL7702). The effects were further proved in vivo without systemic cytotoxicity. Notably, the responsive environment for drug release depended on the concentration of carriers. Particularly, drug release was promoted by carrier separation. Carrier 2 exhibited preferable anticancer efficacy than carrier 1 due to the efficient release of Dox by full separation of the carrier. Collectively, we have developed a novel strategy serving as a selective and controlled drug release platform for cancer therapeutics.

10.
Cell Mol Immunol ; 2019 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-31467416

RESUMO

Comprehensive immune responses are essential for eliminating pathogens but must be tightly controlled to avoid sustained immune activation and potential tissue damage. The engagement of TLR4, a canonical pattern recognition receptor, has been proposed to trigger inflammatory responses with different magnitudes and durations depending on TLR4 cellular compartmentalization. In the present study, we identify an unexpected role of Lamtor5, a newly identified component of the amino acid-sensing machinery, in modulating TLR4 signaling and controlling inflammation. Specifically, Lamtor5 associated with TLR4 via their LZ/TIR domains and facilitated their colocalization at autolysosomes, preventing lysosomal tethering and the activation of mTORC1 upon LPS stimulation and thereby derepressing TFEB to promote autophagic degradation of TLR4. The loss of Lamtor5 was unable to trigger the TFEB-driven autolysosomal pathway and delay degradation of TLR4, leading to sustained inflammation and hence increased mortality among Lamtor5 haploinsufficient mice during endotoxic shock. Intriguingly, nutrient deprivation, particularly leucine deprivation, blunted inflammatory signaling and conferred protection to endotoxic mice. This effect, however, was largely abrogated upon Lamtor5 deletion. We thus propose a homeostatic function of Lamtor5 that couples pathogenic insults and nutrient availability to optimize the inflammatory response; this function may have implications for TLR4-associated inflammatory and metabolic disorders.

11.
PLoS One ; 14(8): e0221075, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31415631

RESUMO

Vector tile technology is developing rapidly and has received increasing attention in recent years. Compared to the raster tile, the vector tile has shown incomparable advantages, such as flexible map styles, suitability for high-resolution screens and ease of interaction. Recent studies on vector tiles have mostly focused on improving the efficiency on the server side and have overlooked the efficiency on the client side, which affects user experience. Parallel computing provides solutions to this issue. Parallel visualization of vector tiles is a typical example of embarrassing parallelism; thus, estimating the computing times of each tile accurately and decomposing the workload into multiple computing units evenly are key to the parallel visualization of vector tiles. This article adopts mainstream parallel computing and proposes an efficient tile-based parallel method for accelerating geographical feature visualization by building computational weight functions (CWFs) of geographical feature visualizations. The computing time of each vector tile is estimated by the CWF, and an effective workload decomposition strategy is proposed such that the efficiency of vector tile visualization is improved on the client side. Furthermore, a tile-based reconstruction scheme for geographical features is also proposed. Experiments show that the R-squared value of the estimated computing times of vector tiles is 0.914 and that the computational efficiency of the parallel visualization of vector tiles with the proposed workload decomposition strategy is 18.6% higher than that of common parallel visualization. Finally, users can obtain the entire set of features effectively and accurately based on the proposed reconstruction scheme.

12.
Neuromolecular Med ; 2019 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-31401719

RESUMO

Parkinson's disease (PD), the most common neurodegenerative movement disorder, is characterized by the progressive loss of dopaminergic neurons in substantia nigra. The underlying mechanisms of PD pathogenesis have not been fully illustrated and currently PD remains incurable. Accumulating evidences suggest that mitochondrial dysfunction plays pivotal role in the dopaminergic neuronal death. Therefore, discovery of novel and safe agent for rescuing mitochondrial dysfunction would benefit PD treatment. Here we demonstrated for the first time that α-Arbutin (Arb), a natural polyphenol extracted from Ericaceae species, displayed significant protective effect on the rotenone (Rot)-induced mitochondrial dysfunction and apoptosis of human neuroblastoma cell (SH-SY5Y). We further found that the neuroprotective effect of Arb was associated with ameliorating oxidative stress, stabilizing of mitochondrial membrane potential, and enhancing adenosine triphosphate production. To investigate the underlying mechanism, we checked the AMP-activated protein kinase and autophagy pathway and we found that both were involved in the neuroprotection of Arb. Moreover, we explored the protective effect of Arb in drosophila PD model and found that Arb rescued parkin deficiency-induced motor function disability and mitochondrial abnormality of drosophila. Taken together, our study demonstrated that Arb got excellent neuroprotective effect on PD models both in vitro and in vivo and Arb might serve as a potent therapeutic agent for the treatment of PD.

13.
Chem Commun (Camb) ; 55(73): 10920-10923, 2019 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-31441463

RESUMO

The development of new NIR-II fluorophores, particularly those with facile syntheses, high fluorescence quantum yields, and stable and tunable photophysical properties, is challenging. Herein, we report a new class of small molecular NIR-II fluorophores based on aza-dipyrromethene boron difluoride (aza-BODIPY) dyes. We demonstrate promising photophysical properties of these dyes, such as large Stokes shift, superior photostability, and good fluorescence brightness as nanoparticles in aqueous solution. Because of these properties and high resolution and deep penetration NIR-II imaging ability, the aza-BODIPY based dyes show great potential as NIR-II imaging agents.


Assuntos
Compostos de Boro/química , Corantes Fluorescentes/química , Imagem Óptica/métodos , Pirróis/química , Animais , Compostos de Boro/síntese química , Compostos de Boro/efeitos da radiação , Compostos de Boro/toxicidade , Linhagem Celular Tumoral , Teoria da Densidade Funcional , Desenho de Drogas , Fluorescência , Corantes Fluorescentes/síntese química , Corantes Fluorescentes/efeitos da radiação , Corantes Fluorescentes/toxicidade , Raios Infravermelhos , Camundongos , Modelos Químicos , Nanopartículas/química , Poloxâmero/química , Pirróis/síntese química , Pirróis/efeitos da radiação , Pirróis/toxicidade
14.
Nanoscale ; 11(30): 14118-14122, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31318006

RESUMO

The ability to switch the hydrophilicity/hydrophobicity of nanoparticles promises great potential for applications. Here we report a generic approach that allows hydrophobization of cationic surfaces by light-induced photoacid switching from the unbound zwitterionic form to the electrostatically bound anionic form. Importantly, this allows reversible assembly and disassembly of cationic AuNPs, with disassembly kinetics controlled by temperature. The AuNPs can be repeatedly transferred between aqueous and non-polar solvents using light, showing potential in purification processes. In the macroscopic scale, nontrivially, light triggers the in situ hydrophobization of a flat cationized gold surface. The current approach is generic and opens up a new way to control the surface properties and self-assembly of nanoparticles.

15.
Yi Chuan ; 41(6): 469-485, 2019 Jun 20.
Artigo em Chinês | MEDLINE | ID: mdl-31257196

RESUMO

The field of circular non-coding RNAs have been gradually attracted wide attention with the developments of high-throughput sequencing. In this review, we systematically summarize three driving models for circRNAs biogenesis: intron-pairing-driven, RNA binding protein-driven and lariat-driven. In addition, we also briefly introduce the current research methods of circRNAs, which include high-throughput library construction methods, identification through bioinformatics and common experimental verification. Here, we also systematically summarize the functions of circRNAs, including microRNA (miRNA) or protein sponges, regulating the alternative splicing (AS) and expression of host genes, and extensive translation. Finally, we provide a systematic characterization and the latest research progress of circRNAs, which provide a new perspective for further studies of circRNAs in plants.


Assuntos
Processamento Alternativo , RNA/genética , Íntrons , MicroRNAs , Modelos Genéticos , Plantas/genética , Proteínas de Ligação a RNA
16.
Sensors (Basel) ; 19(15)2019 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-31357392

RESUMO

Due to the limitation of the fixed structures of neighborhood windows, the quality of spatial information obtained from the neighborhood pixels may be affected by noise. In order to compensate this drawback, a robust fuzzy c-means clustering with non-neighborhood spatial information (FCM_NNS) is presented. Through incorporating non-neighborhood spatial information, the robustness performance of the proposed FCM_NNS with respect to the noise can be significantly improved. The results indicate that FCM_NNS is very effective and robust to noisy aliasing images. Moreover, the comparison of other seven roughness indexes indicates that the proposed FCM_NNS-based F index can characterize the aliasing degree in the surface images and is highly correlated with surface roughness (R2 = 0.9327 for thirty grinding samples).

17.
Nat Commun ; 10(1): 3267, 2019 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-31332196

RESUMO

Living systems have inspired research on non-biological dynamic materials and systems chemistry to mimic specific complex biological functions. Upon pursuing ever more complex life-inspired non-biological systems, mimicking even the most elementary aspects of learning is a grand challenge. We demonstrate a programmable hydrogel-based model system, whose behaviour is inspired by associative learning, i.e., conditioning, which is among the simplest forms of learning. Algorithmically, associative learning minimally requires responsivity to two different stimuli and a memory element. Herein, nanoparticles form the memory element, where a photoacid-driven pH-change leads to their chain-like assembly with a modified spectral behaviour. On associating selected light irradiation with heating, the gel starts to melt upon the irradiation, originally a neutral stimulus. A logic diagram describes such an evolution of the material response. Coupled chemical reactions drive the system out-of-equilibrium, allowing forgetting and memory recovery. The findings encourage to search non-biological materials towards associative and dynamic properties.

18.
J Cell Biochem ; 120(12): 19832-19840, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31310372

RESUMO

Larynx squamous cell carcinoma (LSCC) is the second most aggressive head and neck squamous cell carcinoma. Numerous genes have been identified to be aberrantly expressed during the development of LSCC. However, currently, researchers focus more on the individual molecule and downstream genes, leaving the coexpression among genes and key upstream disease driver genes unexploited. In this study, we applied weighted gene coexpression analysis (WGCNA) to decipher potential hub genes driving the development of LSCC. After downloading of LSCC microarray profile from gene expression omnibus, different expression analysis was performed, which was used to conduct functional enrichment analysis. Then, we applied WGCNA to highlight the hub genes which were relevant to the carcinogenesis and progression. A total of 2858 differentially expressed genes were identified in LSCC samples compared with adjacent non-neoplastic tissues. WGCNA revealed three LSCC set-specific modules having significant Kyoto Encyclopedia of Genes and Genomes enrichment effect, including pink, cyan, and black module. Nine hub genes were identified to be crucial in LSCC onset and progression, which may assist clinical decisions and serve as potential targets for LSCC treatment.

19.
Sheng Li Xue Bao ; 71(3): 454-462, 2019 Jun 25.
Artigo em Chinês | MEDLINE | ID: mdl-31218336

RESUMO

Neural stem cell therapy, as a new therapeutic method for neural diseases, has aroused a wide concern for over 20 years since neural stem cells were first found in 1992. Ischemic stroke is highly concerned because of its high incidence, mortality and disability rates. Because the brain has a limited ability to repair itself, to improve neural function and promote neural regeneration may help to prevent occurrence and development of neurological diseases. It is noteworthy that some stroke patients showed an ability to repair brain several months after the stroke happened, suggesting an existence of endogenous nerve repair in these patients. The research advances in functions of endogenous neural stem cells in neural regeneration and the related regulators after ischemic stroke are summarized in this review to provide new views of the mechanism of neural functional recovery after ischemic stroke.


Assuntos
Isquemia Encefálica/terapia , Regeneração Nervosa , Células-Tronco Neurais/citologia , Acidente Vascular Cerebral/terapia , Humanos
20.
Life Sci ; 231: 116539, 2019 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-31176779

RESUMO

OBJECTIVE: Although SET(I2PP2A) and miRNAs are reported to play a pivotal role in lung cancer, the underlying mechanisms have remained obscure. To address this issue, we investigated how miRNAs and SET participate in the progression of lung cancer. METHODS: miRNAs that target SET were predicted from multiple miRNA databases. Three human NSCLC cell lines and two normal lung cell lines were used to evaluate aberrant miRNA and SET expressions. A dual luciferase reporter assay system was employed to verify the interaction between miRNA and SET. Stable miRNA knockdown and SET overexpression in A549 cells were achieved through lentivirus transfection; the corresponding influences on lung cancer progression were also examined. RESULTS: In this study, A549 was the sole cell line to lack SET/TAF-Iα expression, which was inversely correlated with the up-regulation of miR-21-5p. SET was subsequently revealed as the direct target site of miR-21-5p in A549 cells. The stable miR-21-5p knockdown and SET/TAF-Iα overexpression were shown to markedly enhance the expression of SET/TAF-Iα and to inhibit the migration, invasion, proliferation as well as the in vivo tumorigenicity of A549 cells. CONCLUSION: We suggest that SET/TAF-Iα might be a tumor suppressing factor regulated by miR-21-5p in lung adenocarcinoma. This might provide a target for lung adenocarcinoma therapy.


Assuntos
Adenocarcinoma de Pulmão/genética , Adenocarcinoma de Pulmão/metabolismo , Chaperonas de Histonas/metabolismo , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Fatores de Transcrição/metabolismo , Células A549 , Adenocarcinoma de Pulmão/patologia , Animais , Apoptose/fisiologia , Linhagem Celular , Linhagem Celular Tumoral , Movimento Celular/fisiologia , Proliferação de Células/fisiologia , Progressão da Doença , Feminino , Humanos , Neoplasias Pulmonares/patologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Invasividade Neoplásica
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