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1.
Artigo em Inglês | MEDLINE | ID: mdl-31944516

RESUMO

The electrochemical CO2 reduction reaction (CO2 RR) to give C1 (formate and CO) products is one of the most techno-economically achievable strategies for alleviating CO2 emissions. Now, it is demonstrated that the SnOx shell in Sn2.7 Cu catalyst with a hierarchical Sn-Cu core can be reconstructed in situ under cathodic potentials of CO2 RR. The resulting Sn2.7 Cu catalyst achieves a high current density of 406.7±14.4 mA cm-2 with C1 Faradaic efficiency of 98.0±0.9 % at -0.70 V vs. RHE, and remains stable at 243.1±19.2 mA cm-2 with a C1 Faradaic efficiency of 99.0±0.5 % for 40 h at -0.55 V vs. RHE. DFT calculations indicate that the reconstructed Sn/SnOx interface facilitates formic acid production by optimizing binding of the reaction intermediate HCOO* while promotes Faradaic efficiency of C1 products by suppressing the competitive hydrogen evolution reaction, resulting in high Faradaic efficiency, current density, and stability of CO2 RR at low overpotentials.

2.
J Chem Phys ; 151(21): 214704, 2019 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-31822092

RESUMO

Under the oxidizing condition, the cheap metal component of bimetallic catalysts often segregates to the surface and forms oxide nanoclusters (NCs) supported on the metal surface, which exhibit unique structures and catalytic properties drastically different from the corresponding bulk materials. Here, density functional theory calculations are employed to describe the atomic and electronic structures of a series of triangular FeOx NCs confined on Pt(111) with the size ranging from ∼0.3 nm to ∼2.2 nm, which behave differently from the FeO film reported previously. The lattice of supported FeOx NCs on Pt(111) is found to vary not only with the NC size but also with the Fe/O ratio or the edge termination. Owing to a strong FeOx-Pt interaction, the heterogeneous distribution of local atomic and electronic structures of Fe across the FeOx NC is observed, though most of Fe atoms are positioned at the threefold hollow site of Pt(111). Our study not only sheds light on the catalytically active sites of supported FeOx NCs but also provides guidance for the design of highly active and stable oxide nanocatalysts under reactive environment.

3.
Mol Immunol ; 116: 73-79, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31630078

RESUMO

Atherosclerosis is a common comorbidity of type II diabetes and a leading cause of death worldwide. The presence of oxidized low-density lipoprotein (ox-LDL) drives atherogenesis by inducing oxidative stress, mitochondrial dysfunction, expression of proinflammatory cytokines and chemokines including interleukin (IL)-1ß, IL-6, and monocyte chemoattractant protein 1 (MCP-1), adhesion molecules including vascular cellular adhesion molecule 1 (VCAM-1) and E-selectin, and downregulating expression of the Krüppel-like factor 2 (KLF2) transcription factor. Importantly, ox-LDL induced the attachment of THP-1 monocytes to endothelial cells. In the present study, we demonstrate for the first time that the specific glucagon-like peptide 1 receptor (GLP-1R) agonist dulaglutide may prevent these atherosclerotic effects of ox-LDL by preventing suppression of KLF2 by p53 protein in human aortic endothelial cells. KLF2 has been shown to play a major role in protecting vascular endothelial cells from damage induced by ox-LDL and oscillatory shear, and therefore, therapies capable of mediating KLF2 signaling may be an attractive treatment option for preventing the development and progression of atherosclerosis.


Assuntos
Aterosclerose/tratamento farmacológico , Receptor do Peptídeo Semelhante ao Glucagon 1/metabolismo , Peptídeos Semelhantes ao Glucagon/análogos & derivados , Fragmentos Fc das Imunoglobulinas/farmacologia , Lipoproteínas LDL/metabolismo , Monócitos/efeitos dos fármacos , Proteínas Recombinantes de Fusão/farmacologia , Aterosclerose/metabolismo , Adesão Celular , Células Cultivadas , Citocinas/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Células Endoteliais , Regulação da Expressão Gênica/efeitos dos fármacos , Peptídeos Semelhantes ao Glucagon/farmacologia , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Fatores de Transcrição Kruppel-Like/metabolismo , Monócitos/metabolismo , NF-kappa B/metabolismo , Transdução de Sinais/efeitos dos fármacos , Molécula 1 de Adesão de Célula Vascular/metabolismo
4.
Adv Sci (Weinh) ; 6(19): 1900775, 2019 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-31592413

RESUMO

Solution-processed 2D organic semiconductors (OSCs) have drawn considerable attention because of their novel applications from flexible optoelectronics to biosensors. However, obtaining well-oriented sheets of 2D organic materials with low defect density still poses a challenge. Here, a highly crystallized 2,9-didecyldinaphtho[2,3-b:2',3'-f]thieno[3,2-b]thiophene (C10-DNTT) monolayer crystal with large-area uniformity is obtained by an ultraslow shearing (USS) method and its growth pattern shows a kinetic Wulff's construction supported by theoretical calculations of surface energies. The resulting seamless and highly crystalline monolayers are then used as templates for thermally depositing another C10-DNTT ultrathin top-up film. The organic thin films deposited by this hybrid approach show an interesting coherence structure with a copied molecular orientation of the templating crystal. The organic field-effect transistors developed by these hybrid C10-DNTT films exhibit improved carrier mobility of 14.7 cm2 V-1 s-1 as compared with 7.3 cm2 V-1 s-1 achieved by pure thermal evaporation (100% improvement) and 2.8 cm2 V-1 s-1 achieved by solution sheared monolayer C10-DNTT. This work establishes a simple yet effective approach for fabricating high-performance and low-cost electronics on a large scale.

5.
Adv Mater ; 31(44): e1904073, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31544295

RESUMO

As competing with the established silicon technology, organic-inorganic metal halide perovskites are continually gaining ground in optoelectronics due to their excellent material properties and low-cost production. The ability to have control over their shape, as well as composition and crystallinity, is indispensable for practical materialization. Many sophisticated nanofabrication methods have been devised to shape perovskites; however, they are still limited to in-plane, low-aspect-ratio, and simple forms. This is in stark contrast with the demands of modern optoelectronics with freeform circuitry and high integration density. Here, a nanoprecision 3D printing is developed for organic-inorganic metal halide perovskites. The method is based on guiding evaporation-induced perovskite crystallization in mid-air using a femtoliter ink meniscus formed on a nanopipette, resulting in freestanding 3D perovskite nanostructures with a preferred crystal orientation. Stretching the ink meniscus with a pulling process enables on-demand control of the nanostructure's diameter and hollowness, leading to an unprecedented tubular-solid transition. With varying the pulling direction, a layer-by-layer stacking of perovskite nanostructures is successfully demonstrated with programmed shapes and positions, a primary step for additive manufacturing. It is expected that the method has the potential to create freeform perovskite nanostructures for customized optoelectronics.

6.
Mol Med Rep ; 20(4): 3910-3916, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31432135

RESUMO

Willed movement facilitates neurological rehabilitation in patients with stroke. Focal ischaemia is the hallmark of patients after stroke, though the detailed molecular mechanism by which willed movement affects neurological rehabilitation after stroke is not fully understood. The aim of the present study was to dissect the key factors of the hypoxia signaling pathway responsible for the willed movement­improved rehabilitation. Sprague­Dawley rats undergoing right middle cerebral artery occlusion (MCAO) surgery were randomly divided into four groups: MCAO alone, willed movement (WM), environmental modification (EM) and common rehabilitation (CR). The neurological behaviour score was assessed, and infarction areas were detected by TTC staining. In addition, angiogenesis­associated genes (vascular epithelial growth factor, angiogenin­1, matrix metalloproteinases­2 and ­9) and hypoxia inducible factor (HIF)­1α expression was investigated in cells derived from MCAO, WM, EM and CR groups. Finally, the role of HIF­1α using HIF­1α knockdown in HUVECs under hypoxic conditions was evaluated. WM significantly improved neurological behaviour and rehabilitation by increasing the behaviour score and by decreasing the infarction area. In addition, CR, EM and WM raised the expression of angiogenesis­associated genes and HIF­1α, thereby promoting in vitro tube formation of primary endothelial cells. Knockdown of HIF­1α in HUVECs restored the increased expression of angiogenesis­associated genes to normal levels and inhibited in vitro tube formation of HUVECs. Willed movement most effectively improved the neurological rehabilitation of rats with focal ischaemia through upregulation of HIF­1α. The present findings provide insight into willed movement­facilitated rehabilitation and may help treat stroke­triggered motor deficit and improve angiogenesis of cerebral endothelial cells.

7.
Adv Mater ; 31(24): e1807689, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31033074

RESUMO

The quality of perovskite films is critical to the performance of perovskite solar cells. However, it is challenging to control the crystallinity and orientation of solution-processed perovskite films. Here, solution-phase van der Waals epitaxy growth of MAPbI3 perovskite films on MoS2 flakes is reported. Under transmission electron microscopy, in-plane coupling between the perovskite and the MoS2 crystal lattices is observed, leading to perovskite films with larger grain size, lower trap density, and preferential growth orientation along (110) normal to the MoS2 surface. In perovskite solar cells, when perovskite active layers are grown on MoS2 flakes coated on hole-transport layers, the power conversion efficiency is substantially enhanced for 15%, relatively, due to the increased crystallinity of the perovskite layer and the improved hole extraction and transfer rate at the interface. This work paves a way for preparing high-performance perovskite solar cells and other optoelectronic devices by introducing 2D materials as interfacial layers.

8.
Int J Mol Sci ; 20(3)2019 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-30759771

RESUMO

Astrocytes are major glial cells that play critical roles in brain homeostasis. Abnormalities in astrocytic functions can lead to brain disorders. Astrocytes also respond to injury and disease through gliosis and immune activation, which can be both protective and detrimental. Thus, it is essential to elucidate the function of astrocytes in order to understand the physiology of the brain to develop therapeutic strategies against brain diseases. Cyclic adenosine monophosphate (cAMP) is a major second messenger that triggers various downstream cellular machinery in a wide variety of cells. The functions of astrocytes have also been suggested as being regulated by cAMP. Here, we summarize the possible roles of cAMP signaling in regulating the functions of astrocytes. Specifically, we introduce the ways in which cAMP pathways are involved in astrocyte functions, including (1) energy supply, (2) maintenance of the extracellular environment, (3) immune response, and (4) a potential role as a provider of trophic factors, and we discuss how these cAMP-regulated processes can affect brain functions in health and disease.


Assuntos
Astrócitos/metabolismo , Encefalopatias/metabolismo , AMP Cíclico/metabolismo , Transdução de Sinais/fisiologia , Animais , Astrócitos/fisiologia , Encéfalo/metabolismo , Encéfalo/fisiologia , Encefalopatias/patologia , Humanos , Imunidade/fisiologia
9.
Small ; 15(8): e1804465, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30690887

RESUMO

The photovoltaic performance of perovskite solar cells is highly dependent on the control of morphology and crystallization of perovskite film, which usually requires a controlled atmosphere. Therefore, fully ambient fabrication is a desired technology for the development of perovskite solar cells toward real production. Here, an air-knife assisted recrystallization method is reported, based on a simple bath-immersion to prepare high-quality perovskite absorbers. The resulted film shows a strong crystallinity with pure domains and low trap-state density, which contribute to the device performance and stability. The proposed method can operate in a wide process window, such as variable relative humidity and bath-immersion conditions, demonstrating a power conversion efficiency over 19% and 27% under 1 sun and 500-2000 lux dim-light illumination respectively, which is among the highest performance of ambient-process perovskite solar cells.

10.
Brain Res ; 1707: 90-98, 2019 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-30408478

RESUMO

OBJECTIVE: The present study was designed to investigate the mechanism by which lncRNA NEAT1 regulates survival and angiogenesis in oxygen-glucose deprivation (OGD)-induced brain microvascular endothelial cells (BMECs). METHODS: OGD-treated BMECs were used to mimic cerebral ischaemia in vitro. The expression of lncRNA NEAT1 and miR-377 and proteins including VEGFA, SIRT1, and BCL-XL were measured by real-time quantitative PCR (qRT-PCR) and western blot, respectively. Cell viability and caspase 3 activity of BMECs under different conditions were determined using MTT and caspase activity assays, respectively. Matrigel-based angiogenesis assays were employed to evaluate the effect of lncRNA NEAT1 on angiogenesis. A dual-luciferase reporter assay was used to validate direct binding of miR-377 to putative targets. RESULTS: OGD exposure reduced the cell viability of BMECs. Upregulation of lncRNA NEAT1 and downregulation of miR-377 were also observed under OGD conditions. Knockdown of lncRNA NEAT1 inhibited angiogenesis and aggravated apoptosis in OGD-induced BMECs. Meanwhile, the expression level of miR-377 was upregulated while its downstream targets (VEGFA, SIRT1, and BCL-XL) were downregulated after lncRNA NEAT1 knockdown. Furthermore, miR-377 inhibited the angiogenesis and survival of OGD-induced BMECs. The expression of VEGFA, SIRT1, and BCL-XL were all attenuated by miR-377 overexpression. The dual-luciferase reporter assay proved miR-377 targeted the 3' UTR sequences of lncRNA NEAT1, VEGFA, SIRT1, and BCL-XL. CONCLUSION: lncRNA NEAT1 facilitated the survival and angiogenesis of OGD-induced BMECs via targeting miR-377 and promoting the expression of VEGFA, SIRT1, and BCL-XL, suggesting that lncRNA NEAT1 could be a promising target for cerebral ischaemia treatment.

11.
Molecules ; 23(12)2018 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-30558186

RESUMO

Antibiotic resistance has become a serious global problem that threatens public health. In our previous work, we found that ocotillol-type triterpenoid saponin showed good antibacterial activity. Based on preliminary structure-activity relationship, novel serious C-3 substituted ocotillol-type derivatives 7⁻26 were designed and synthesized. The in vitro antibacterial activity was tested on five bacterial strains (B. subtilis 168, S. aureus RN4220, E. coli DH5α, A. baum ATCC19606 and MRSA USA300) and compared with the tests on contrast. Among these derivatives, C-3 position free hydroxyl substituted compounds 7⁻14, showed good antibacterial activity against Gram-positive bacteria. Furthermore, compound 22 exhibited excellent antibacterial activity with minimum inhibitory concentrations (MIC) values of 2 µg/mL against MRSA USA300 and 4 µg/mL against B. subtilis. The structure-activity relationships of all current ocotillol-type derivatives our team synthesised were summarized. In addition, the prediction of absorption, distribution, metabolism, and excretion (ADME) properties and the study of pharmacophores were also conducted. These results can provide a guide to further design and synthesis works.


Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Ginsenosídeos/química , Bacillus subtilis/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Staphylococcus aureus/efeitos dos fármacos , Relação Estrutura-Atividade
12.
Sensors (Basel) ; 18(9)2018 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-30223509

RESUMO

To cope with the complex electromagnetic environment and varied signal styles, a novel method based on the energy cumulant of short time Fourier transform and reinforced deep belief network is proposed to gain a higher correct recognition rate for radar emitter intra-pulse signals at a low signal-to-noise ratio. The energy cumulant of short time Fourier transform is attained by calculating the accumulations of each frequency sample value with the different time samples. Before this procedure, the time frequency distribution via short time Fourier transform is processed by base noise reduction. The reinforced deep belief network is proposed to employ the input feature vectors for training to achieve the radar emitter recognition and classification. Simulation results manifest that the proposed method is feasible and robust in radar emitter recognition even at a low SNR.

13.
ACS Appl Mater Interfaces ; 10(41): 35395-35403, 2018 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-30234961

RESUMO

Crystals of organic semiconductors are excellent candidates for flexible and array-based electronics. Large-scale synthesis of organic crystals in a controllable way while maintaining homogeneous single-crystal property has been a great challenge. The existence of grain boundaries and small crystal domains, however, restrict the device performance and limit the access to commercially viable organic electronics in the industry. Herein, we report the inch-scale synthesis of highly oriented 2,7-dioctyl[1]benzothieno[3,2- b][1]benzothiophene (C8-BTBT) organic single crystal by nucleation seed-controlled shearing method. The organic field-effect transistors developed from such single crystal have excellent carrier mobility as high as 14.9 cm2 V-1 s-1 and uniformity (standard deviation is 1.3 cm2 V-1 s-1) of 225 devices. We also found that the rotation of the principal axis in the crystal is governed by the orientations of seeds and the possible mechanism behind this phenomenon is proposed based on the density functional theory calculations. We anticipate that this proposed approach will have great potential to be developed as a platform for the growth of organic crystals with high crystallinity on a large scale.

14.
Environ Sci Technol ; 52(16): 9341-9349, 2018 08 21.
Artigo em Inglês | MEDLINE | ID: mdl-30043615

RESUMO

Conventional thin-film composite (TFC) membranes suffer from the trade-off relationship between permeability and selectivity, known as the "upper bound". In this work, we report a high performance thin-film composite membrane prepared on a tannic acid (TA)-Fe nanoscaffold (TFCn) to overcome such upper bound. Specifically, a TA-Fe nanoscaffold was first coated onto a polysulfone substrate, followed by performing an interfacial polymerization reaction between trimesoyl chloride (TMC) and piperazine (PIP). The TA-Fe nanoscaffold enhanced the uptake of amine monomers and provided a platform for their controlled release. The smaller surface pore size of the TA-Fe coated substrate further eliminated the intrusion of polyamide into the substrate pores. The resulting membrane TFCn showed a water permeability of 19.6 ± 0.5 L m2- h-1 bar-1, which was an order of magnitude higher than that of control TFC membrane (2.2 ± 0.3 L m-2 h-1 bar-1). The formation of a more order polyamide rejection layer also significantly enhanced salt rejection (e.g., NaCl, MgCl2, Na2SO4, and MgSO4) and divalent to monovalent ion selectivity (e.g., NaCl/MgSO4). Compared to conventional TFC nanofiltration membranes, the novel TFCn membrane successfully overcame the longstanding permeability and selectivity trade-off. The current work paves a new avenue for fabricating high performance TFC membranes.


Assuntos
Membranas Artificiais , Taninos , Nylons , Permeabilidade , Polimerização
15.
Org Lett ; 20(14): 4231-4234, 2018 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-29953242

RESUMO

An efficient transition-metal-free oxidative cyclization reaction using isatins and alkynes for the facile synthesis of structurally diverse 4-quinolones has been developed. Intriguingly, switchable access to substituted 3-carboxylate-4-quinolones and 1-vinyl-3-carboxylate-4-quinolones could be achieved by choosing a different base in the reaction. The obtained products could undergo further transformations, increasing the application potential of the method in organic synthesis.

16.
Sci Rep ; 8(1): 7708, 2018 05 16.
Artigo em Inglês | MEDLINE | ID: mdl-29769621

RESUMO

Hypovitaminosis D is associated with age-related illnesses, including hypertension, cardiovascular disease (CRVD), cerebrovascular disease (CAD) and type 2 diabetes mellitus (T2DM). In our retrospective observational study, blood samples of elderly healthy controls (n = 461) and patients with age-related diseases (n = 8,621) were subjected to flow-cytometry in order to determine correlations between age-related diseases and cluster of differentiation 4 (CD4), CD8, CD3, and CD19 lymphocyte markers, as well as serum levels of 25-hydroxyvitamin D2 (25(OH)D2) and 25-hydroxyvitamin D3 (25(OH)D3). More than 70% of the patients in each disease group had total vitamin D < 20 ng/mL (P < 0.001). In CRVD patients, CD3 and CD19 correlated (P < 0.05) with 25(OH)D3. In CAD patients, CD8, CD4, CD19 and CD4/CD8 correlated (P < 0.05) with 25(OH)D2, and CD8 correlated (P < 0.05) with 25(OH)D3. In T2DM and hypertension patients, CD8, CD3, CD19 and CD4/CD8 correlated with 25(OH)D3. Progressive trends (P < 0.05) towards increased CD8 and CD4/CD8 were observed in vitamin-D-deficient T2DM and hypertension patients. Significant differences (P < 0.05) in CD8 were observed in vitamin-D-deficient CAD patients, whereas significant differences (P < 0.05) in CD8 and CD19 were observed in CRVD patients. Higher CD8 and CD4/CD8 in 25(OH)D-deficient T2DM and hypertension patients suggested a Th1 lymphocyte profile induction. Increases in CD8-positive lymphocytes suggested a similar, less pronounced effect in vitamin-D-deficient CRVD and CAD patients.


Assuntos
Doenças Cardiovasculares/sangue , Transtornos Cerebrovasculares/sangue , Diabetes Mellitus Tipo 2/sangue , Hipertensão/sangue , Subpopulações de Linfócitos/imunologia , Deficiência de Vitamina D/sangue , Vitamina D/sangue , Idoso , Idoso de 80 Anos ou mais , Envelhecimento , Biomarcadores/análise , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/imunologia , Estudos de Casos e Controles , Transtornos Cerebrovasculares/epidemiologia , Transtornos Cerebrovasculares/imunologia , Diabetes Mellitus Tipo 2/epidemiologia , Diabetes Mellitus Tipo 2/imunologia , Feminino , Humanos , Hipertensão/epidemiologia , Hipertensão/imunologia , Masculino , Estudos Retrospectivos , Deficiência de Vitamina D/epidemiologia , Deficiência de Vitamina D/imunologia , Vitaminas/sangue
17.
Adv Mater ; 30(13): e1706647, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29424125

RESUMO

Organic optical memory devices keep attracting intensive interests for diverse optoelectronic applications including optical sensors and memories. Here, flexible nonvolatile optical memory devices are developed based on the bis[1]benzothieno[2,3-d;2',3'-d']naphtho[2,3-b;6,7-b']dithiophene (BBTNDT) organic field-effect transistors with charge trapping centers induced by the inhomogeneity (nanosprouts) of the organic thin film. The devices exhibit average mobility as high as 7.7 cm2 V-1 s-1 , photoresponsivity of 433 A W-1 , and long retention time for more than 6 h with a current ratio larger than 106 . Compared with the standard floating gate memory transistors, the BBTNDT devices can reduce the fabrication complexity, cost, and time. Based on the reasonable performance of the single device on a rigid substrate, the optical memory transistor is further scaled up to a 16 × 16 active matrix array on a flexible substrate with operating voltage less than 3 V, and it is used to map out 2D optical images. The findings reveal the potentials of utilizing [1]benzothieno[3,2-b][1]benzothiophene (BTBT) derivatives as organic semiconductors for high-performance optical memory transistors with a facile structure. A detailed study on the charge trapping mechanism in the derivatives of BTBT materials is also provided, which is closely related to the nanosprouts formed inside the organic active layer.

18.
Mol Med Rep ; 17(1): 1173-1181, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29115485

RESUMO

Neurorehabilitation training is a therapeutic intervention for the loss of neural function induced by focal cerebral ischemia, however, the effect varies depending on the neurorehabilitation exercises. Willed movement (WM) training is defined as task­oriented training, which increases enthusiasm of patients to accomplish a specific task. The current study was performed to the evaluate effect of WM training on neurorehabilitation following focal cerebral ischemia, and further investigate the influence on neural plasticity­associated signaling pathway. Sprague­Dawley rats following temporary middle cerebral artery occlusion (tMCAO) were randomly divided into four groups: tMCAO (no rehabilitation training), CR (control rehabilitation), EM (environmental modification) and WM groups. Rats in the CR group were forced to exercise (running) in a rotating wheel. In the WM group, food was used to entice rats to climb on a herringbone ladder. Herringbone ladders were also put into the cages of the rats in the CR and EM groups, however without the food attraction. WM group exhibited an improvement in neurobehavioral performance compared with other groups. TTC staining indicated an evident reduction in brain damage in the WM group. There were increased synaptic junctions following WM training, based on the observations of transmission election microscopy. Investigation of the molecular mechanism suggested that WM training conferred the greatest effect on stimulating the extracellular signal­related kinase (ERK)/cyclic adenosine monophosphate response element­binding protein 1 (CREB) pathway and glutamate receptor 2 (GluR2)/glutamate receptor interacting protein 1­associated protein 1 (GRASP­1)/protein interacting with C­kinase 1 (PICK1) cascades among groups. Collectively, the improvement of neurobehavioral performance by WM training following tMCAO is suggested to involve the ERK/CREB pathway and GluR2/GRASP­1/PICK1 cascades. The present study provided a preliminary foundation for future research on the therapeutic effect of WM training against stroke­induced neuron damage.


Assuntos
Isquemia Encefálica/metabolismo , Isquemia Encefálica/reabilitação , Plasticidade Neuronal , Condicionamento Físico Animal , Transdução de Sinais , Animais , Encéfalo/metabolismo , Encéfalo/patologia , Encéfalo/ultraestrutura , Isquemia Encefálica/etiologia , Isquemia Encefálica/patologia , Imunofluorescência , Imuno-Histoquímica , Masculino , Mortalidade , Força Muscular , Ratos
19.
J Thorac Dis ; 10(11): 6050-6059, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30622776

RESUMO

Background: To assess the association between coronary artery atherosclerosis (CAA) and plasma glucose parameters in a randomly selected cohort of asymptomatic, community-dwelling, Chinese adults by dual-source computed tomography (DSCT). Methods: We randomly selected participants and classified them into three groups based on their plasma glucose levels: normal glucose regulation (NGR), pre-diabetes, and diabetes mellitus (DM). The participants underwent DSCT, and those identified with CAA were divided into four groups according to the severity of their coronary artery stenosis. We analyzed the composition of plaques in all coronary artery segments according to the American Heart Association's (AHA) guidelines. We compared the severity of coronary artery stenosis and the plaque composition with plasma glucose parameters among participants. Results: Out of a total of 335 participants, 118 were found to have CAA. The prevalence of CAA was highest (P value for trend =0.031) in the diabetic group (67.7%) followed by the pre-diabetic group (35.1%) then the NGR group (27.7%). Both calcified and mixed plaques were found in the coronary arteries of the diabetic group while mixed and non-calcified plaques predominated in the pre-diabetic and the NGR groups. When data from all subjects with CAA were analyzed, blood glucose parameters, fasting plasma glucose (FPG), 2-hr postprandial plasma glucose (PPG), and hemoglobin A1c (HbA1c), exhibited a positive correlation with the severity of coronary stenosis (P<0.05). Multivariable logistic regression models indicated a significantly higher risk of CAA among the diabetic patients. Triglyceride levels were positively correlated with the blood glucose parameters among the three groups while LDL-C was elevated in the DM group but not in the pre-diabetic group compared to the NGR group. Conclusions: The severity of CAA exhibited a direct correlation with the blood glucose parameters, FPG, PPG, and HbA1c. DSCT can accurately detect the presence and distribution of CAA in asymptomatic, community-dwelling subjects. DSCT is a useful screening tool for coronary artery disease (CAD).

20.
ACS Nano ; 11(11): 11449-11458, 2017 11 28.
Artigo em Inglês | MEDLINE | ID: mdl-29035514

RESUMO

The controlled fabrication of nanostructures has often used a substrate template to mediate and control the growth kinetics. Electronic substrate-mediated interactions have been demonstrated to guide the assembly of organic molecules or the nucleation of metal atoms but usually at cryogenic temperatures, where the diffusion has been limited. Combining STM, STS, and DFT studies, we report that the strong electronic interaction between transition metals and oxides could indeed govern the growth of low-dimensional oxide nanostructures. As a demonstration, a series of FeO triangles, which are of the same structure and electronic properties but with different sizes (side length >3 nm), are synthesized on Pt(111). The strong interfacial interaction confines the growth of FeO nanostructures, leading to a discrete size distribution and a uniform step structure. Given the same interfacial configuration, as-grown FeO nanostructures not only expose identical edge/surface structure but also exhibit the same electronic properties, as manifested by the local density of states and local work functions. We expect the interfacial confinement effect can be generally applied to control the growth of oxide nanostructures on transition metal surfaces. These oxide nanostructures of the same structure and electronic properties are excellent models for studies of nanoscale effects and applications.

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