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1.
BMC Ophthalmol ; 20(1): 86, 2020 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-32138784

RESUMO

BACKGROUND: Postoperative nausea and vomiting (PONV) are common side-effects following strabismus surgery. The present study aimed to compare the effects of different doses of dexmedetomidine (DEX) on PONV incidence in pediatric patients undergoing strabismus surgery. METHODS: In this prospective randomized double-blinded study, 126 pediatric patients undergoing strabismus surgery were randomized into one of three groups: Placebo group, normal saline; DEX1 group, 0.3 µg/kg dexmedetomidine, and DEX2 group, 0.5 µg/kg dexmedetomidine. Oculocardiac reflex (OCR) events were recorded during surgery. PONV or postoperative vomiting (POV) was recorded for 24 h in the ward. Pediatric anesthesia emergence delirium (PAED) scale and emergence agitation (EA) scale were recorded in the recovery room. RESULTS: Intraoperative OCR was significantly reduced in DEX2 group (42%) as compared to that of Placebo group (68%) (p = 0.0146). During the first 24 h post-op, the overall incidence of PONV was significantly lower in DEX2 group (10%) than that of Placebo group (32%) (p = 0.0142). There was no significant difference in POV among the three groups. PAED or EA scores among the three groups were similar during recovery time. CONCLUSION: Dexmedetomidine (0.5 µg/kg) reduced OCR and PONV without lengthening extubation time or recovery time in pediatric patients undergoing strabismus surgery. TRIAL REGISTRATION: The trial was prospectively registered before patient enrollment at Chinese Clinical Trial Registry (Clinical Trial Number: ChiCTR1800020176, Date: 12/19/2018).

2.
Artigo em Inglês | MEDLINE | ID: mdl-32176860

RESUMO

Microglia inflammation, involved in the occurrence and development of sepsis-associated encephalopathy, exhibits upregulation of pro-inflammatory cytokines and pro-inflammatory enzymes expression, leading to inflammation-induced neuronal cell apoptosis. TIR domain-containing adapter molecule-2 (TICAM-2), participates in lipopolysaccharide (LPS)-mediated BV2 cells inflammation. SET8 plays a crucial role in a variety of cellular signal pathways. In this study, we hypothesize that SET8 participates in LPS-mediated microglial inflammation via modulation of TICAM-2 expression. Our data indicated that LPS induced BV2 inflammation via upregulation of TICAM-2 expression. Moreover, LPS treatment inhibited SET8 expression, while increased activating transcription factor2 (ATF2) expression. The effects of sh-SET8 and ATF2 overexpression were similar to that of LPS treatments. Inhibition of TICAM-2 expression counteracted sh-SET8-mediated and ATF2 overexpression-mediated BV2 cells inflammation. Further, SET8 was found to interact with ATF2. Mechanistic study found H4K20me1, a downstream target of SET8, and ATF2 enriched at TICAM-2 promoter region. Luciferase reporter assays indicated that sh-SET8 increased TICAM-2 promoter activity, but augmented effect of ATF2 overexpression on TICAM-2 promoter activity as well. Co-transfection of sh-SET8 with ATF2 overexpression more dramatically increased TICAM-2 expression in BV2 cells. The present study indicated that SET8 interacted with ATF2 to modulate TICAM-2 expression, which participated in LPS-mediated BV2 cells inflammation.

3.
Sci Rep ; 10(1): 3522, 2020 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-32103091

RESUMO

Two novel core-shell structured SiO2@AIPA-S-Si-Eu and SiO2@AIPA-S-Si-Eu-phen nanocomposites have been synthesized by a bifunctional organic ligands ((HOOC)2C6H3NHCONH(CH2)3Si(OCH2CH3)3) (defined as AIPA-S-Si) connected with Eu3+ ions and silica via covalent bond. And the corresponding core-shell-shell structured SiO2@AIPA-S-Si-Eu@SiO2 and SiO2@AIPA-S-Si-Eu-phen@SiO2 nanocomposites with enhanced luminescence have been synthesized by tetraethyl orthosilicate (TEOS) hydrolysis co-deposition method. The composition and micromorphology of the nanocomposites were characterized by means of Fourier-transform infrared spectroscopy (FT-IR), thermal gravimetric analysis (TG), X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy-dispersive X-ray spectrometry (EDX) and X-ray photoelectron spectroscopy (XPS). The as-synthesized core-shell and core-shell-shell structured nanocomposites have excellent luminescence intensity and long lifetime. The nanocomposites show bright red light under ultraviolet lamp. However, the core-shell-shell structured nanocomposites have stronger luminescence intensity than the corresponding core-shell structured nanocomposites. Meanwhile, the core-shell-shell structured nanocomposites still exhibit good luminescence stability in aqueous solution. In addition, a large number of Si-OH on the surface of the core-shell-shell structured nanocomposites can be attached to many biomacromolecules. Therefore, they have potential applications in the fields of biology and luminescence.

4.
Artigo em Inglês | MEDLINE | ID: mdl-31972090

RESUMO

Boron particles with a homogeneous carbon-coating layer were employed as the precursor to fabricate MgB2 superconductors to generate artificial two-dimensional (2D) flux-pinning centers. Systematic microstructure investigation reveals that the carbon layers are well-distributed in the MgB2 matrix without agglomeration. The thickness of the carbon layers is smaller than the MgB2 coherent length, which makes them transparent to supercurrent. The critical current density is increased because of the strong flux-pinning effects of the 2D carbon layers in the superconductor as highly efficient flux-pinning centers and the increased irreversibility field due to the carbon-doping effects.

5.
Luminescence ; 35(2): 250-259, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31749285

RESUMO

Four core-shell structured nanometre luminescent composites with different kernel sizes and different shell layer thicknesses (SiO2(500) @Eu (phen-Si)(50) , SiO2(500) @Eu (phen-Si)(15) , SiO2(250) @Eu (phen-Si)(5) and SiO2(250) @Eu (phen-Si)(10) ) were made by changing synthesis conditions. Here, initial subscript numbers in parentheses refer to the particle size of the SiO2 core, whereas the final subscript numbers in parentheses refer to shell layer thickness. In these composites, silica spheres of 500 nm or 250 nm were identified as the core. The shell layer was composited of silicon, 1,10-phenanthroline and europium perchlorate, abbreviated as Eu(phen-Si); the chemical formula of phen-Si was phen-N-(CONH (CH2 )Si(OCH2 CH3 )3 )2 . The composites were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), and infrared spectroscopy. The monodispersed spherical SiO2 showed characteristics of a regular microstructure and a smooth surface, as well as the advantage of dispersity, shown by SEM. The Eu(phen-Si) complex was able to self-assemble into monodispersed SiO2 spheres, as seen using TEM. Fluorescence spectra indicated that the four composites had excellent luminescence properties. Furthermore, composites composed of a SiO2 core and a 250 nm kernel size exhibited stronger fluorescence than 500 nm kernel-sized composites. Fluorescence properties were affected by shell thickness: the thicker the shell, the greater the fluorescence intensity. For the four composites, quantum yield values and fluorescence lifetime corresponded to fluorescence emission intensity data as quantum yield values and fluorescence lifetime were higher, and luminescence properties increased.

6.
J Spinal Cord Med ; 43(1): 130-133, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29323631

RESUMO

Context: Cervical spinal cord infarction is a rare and severe complication of vertebral artery dissection (VAD). We report a case of VAD in an acute stage followed by cervical spinal cord infarction that was treated using direct endovascular tirofiban infusion via digital subtraction angiography (DSA) monitoring.Findings: A 48-year-old man presented with vertigo, neck pain, numbness and weakness in four limbs with subsequent cardiac and respiratory arrest. Neurological examination revealed hypoesthesia below the neck with grade one myodynamia on the right side of the limbs and zero on the left side. The diagnosis of VAD-related cervical spinal infarction was confirmed using DSA imaging and cervical vertebra magnetic resonance imaging (MRI). The patient received timely treatment with endovascular tirofiban infusion and achieved good outcome without any sequelae.Conclusion: Endovascular treatment with tirofiban may be a selective choice for cervical spinal cord infarction due to VAD in acute stage and warrants further study.

7.
Stem Cell Res Ther ; 10(1): 376, 2019 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-31806004

RESUMO

BACKGROUND: The umbilical cord blood (UCB) has been widely accepted as an alternative source of hematopoietic stem/progenitor cells (HSPCs) for transplantation, and its use in adults is still restricted because of low absolute numbers. To overcome this obstacle, expansion of UCB-HSPCs under feeder cell-based coculture is a promising possibility. In this study, we explored UCB-CD34+ cells ex vivo expansion using Wharton's jelly mesenchymal stem cells (WJ-MSCs) or umbilical vein endothelial cells (UVECs) as feeder layer-based serum-free coculture system with a cocktail of cytokines. METHODS: UCB-CD34+ cells were cultured in five different coculture conditions composed of umbilical cord stromal cells (WJ-MSCs or UVECs) with or without a cocktail of cytokines (SCF, FLT3L, and TPO). The cultured cells were harvested at day 10 and analyzed for phenotypes and functionalities, including total nuclear cells (TNCs), CD34+ cells, CD34+CD38- cells, colony-forming unit (CFU) for committed progenitors, and long-term culture initiating cells (LTC-ICs) for HSPCs. RESULTS: Our work showed the numbers of TNC cells, CD34+ cells, and CD34+CD38- cells were expanded under five coculture conditions, and the feeder layer-based cocultures further promoted the expansion. The numbers of colonies of CFU-GM, CFU-E/BFU-E, and CFU-GEMM in the cocultures with cytokines were significantly higher than their counterparts at day 0 (p < 0.05), while no significant difference (p > 0.05) in those without the addition of cytokines. The numbers of LTC-ICs were increased both under the WJ-MSCs and UVECs with cytokine cocultures, but only in the UVECs group showed a significant difference (p < 0.05), and were decreased under conditions without cytokine (p < 0.05). CONCLUSION: Our data demonstrate that both WJ-MSCs and UVECs as feeder layer could efficiently support the expansion of UCB-CD34+ cells in synergy with SCF, FLT3L, and TPO under serum-free culture condition. The UVECs combined with the 3GF cytokine cocktail could maintain the growth of LTC-ICs derived from UCB-CD34+ cells and even expand to some extent.

8.
Small ; : e1903418, 2019 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-31782918

RESUMO

Lithium-ion batteries (LIBs) are widely used in electric vehicles and portable electronic devices due to their high energy density, long cycle life, environmental friendliness, and negligible memory effect, though they also suffer from low power density, safety issues, and an aging effect. Cobalt chalcogenides/phosphides as promising anode materials have attracted intensive interests due to their high theoretical capacity based on the conversion mechanism. Cobaltates (XCo2 O4 , X = the other metal) have attracted attention because the X element can partially replace the high cost and toxic cobalt element. The serious volume variation during the cycling process has an impact, however, on the lithiation environment of above materials. Hierarchical construction can provide more active sites and shorten the diffusion pathways of Li ions as well as accommodating the volume expansion during lithiation processes. Herein, the research progress on the synthesis methods, structural characteristics, and electrochemical performances of cobalt chalcogenides/cobalt phosphides/cobaltates with hierarchical nanostructures for LIBs is presented. The concluding remarks highlight the research challenges and possible development directions of cobalt chalcogenides/cobalt phosphides/cobaltates with tailored hierarchical nanostructures for LIBs.

9.
Small ; : e1903378, 2019 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-31657147

RESUMO

1D nanostructured photoelectrodes are promising for application as photoelectrochemical (PEC) devices for solar energy conversion into hydrogen (H2 ) owing to the optical, structural, and electronic advantages. Titanium dioxide (TiO2 ) is the most investigated candidate as a photoelectrode due to its good photostability, low production cost, and eco-friendliness. The obstacle for TiO2 's practical application is the inherent wide bandgap (UV-lights response), poor conductivity, and limited hole diffusion length. Here, a comprehensive review of the current research efforts toward the development of 1D TiO2 based photoelectrodes for heterogeneous PEC water splitting is provided along with a discussion of nanoarchitectures and energy band engineering influences on interfacial charge transfer and separation of 1D TiO2 composited with different dimensional photoactive materials. The key focus of this review is to understand the charge transfer processes at interfaces and the relationship between photogenerated charge separation and photoelectrochemical performance. It is anticipated that this review will afford enriched information on the rational designs of nanoarchitectures, doping, and heterojunction interfaces for 1D TiO2 based photoelectrodes to achieve highly efficient solar energy conversion.

10.
R Soc Open Sci ; 6(8): 190182, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31598231

RESUMO

Three novel core-shell nanostructured composites SiO2@ANA-Si-Tb, SiO2@ANA-Si-Tb-L (L = second ligand) with SiO2 as the core and terbium organic complex as the shell were successfully synthesized. The core and shell were connected together by covalent bonds. The terbium ion was coordinated with organic ligand-forming terbium organic complex in the shell layer. The organosilane (HOOCC5H4NN(CONH(CH2)3Si(OCH2CH3)3)2 (abbreviated as ANA-Si) was used as the first ligand and 1,10-phenanthroline (phen) or 2-thenoyltrifluoroacetone (TTA) was used as the second ligand. Furthermore, silica-modified SiO2@ANA-Si-Tb@SiO2, SiO2@ANA-Si-Tb-L@SiO2 core-shell-shell nanostructured composites were also synthesized by sol-gel chemical route, which involved the hydrolysis and polycondensation processes of tetraethoxysilane (TEOS) using cetyltrimethyl ammonium bromide (CTAB) as a surface-active agent. An amorphous silica shell was coated around the SiO2@ANA-Si-Tb, SiO2@ANA-Si-Tb-L core-shell nanostructured composites. The core-shell and core-shell-shell nanostructured composites exhibited excellent luminescence in the solid state. Meanwhile, an improved luminescent stability property of the core-shell-shell nanostructured composites was observed for the aqueous solution. This type of core-shell-shell nanostructured composites exhibited bright luminescence, high stability and good solubility, which may present potential applications in the fields of optoelectronic devices, bio-imaging, medical diagnosis and study on the structure of function composite materials.

11.
Sci Rep ; 9(1): 13065, 2019 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-31506509

RESUMO

The novel submicro-spheres SiO2@LaPO4:Eu@SiO2 with core-shell-shell structures were prepared by connecting the SiO2 submicro-spheres and the rare earth ions through an organosilane HOOCC6H4N(CONH(CH2)3Si(OCH2CH3)3 (MABA-Si). The as-prepared products were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), and infrared spectroscopy (IR). It is found that the intermediate shell of the submicro-spheres was composed by LaPO4:Eu nanoparticles with the size of about 4, 5-7, or 15-34 nm. A possible formation mechanism for the SiO2@LaPO4:Eu@SiO2 submicro-spheres has been proposed. The dependence of the photoluminescence intensity on the size of the LaPO4:Eu nanoparticles has been investigated. The intensity ratios of electrical dipole transition 5D0 → 7F2 to magnetic dipole transition 5D0 → 7F1 of Eu3+ ions were increased with decreasing the size of LaPO4:Eu nanoparticles. According to the Judd-Ofelt (J-O) theory, when the size of LaPO4:Eu nanoparticles was about 4, 5-7 and 15-34 nm, the calculated J-O parameter Ω2 (optical transition intensity parameter) was 2.30 × 10-20, 1.80 × 10-20 and 1.20 × 10-20, respectively. The increase of Ω2 indicates that the symmetry of Eu3+ in the LaPO4 lattice was gradually reduced. The photoluminescence intensity of the SiO2@LaPO4:Eu@SiO2 submicro-spheres was unquenched in aqueous solution even after 15 days.

12.
Small ; : e1903380, 2019 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-31532899

RESUMO

Molybdenum carbide (Mox C)-based nanomaterials have shown competitive performances for energy conversion applications based on their unique physicochemical properties. A large surface area and proper surface atomic configuration are essential to explore potentiality of Mox C in electrochemical applications. Although considerable efforts are made on the development of advanced Mox C-based catalysts for energy conversion with high efficiency and stability, some urgent issues, such as low electronic conductivity, low catalytic efficiency, and structural instability, have to be resolved in accordance with their application environments. Surface and interface engineering have shown bright prospects to construct highly efficient Mox C-based electrocatalysts for energy conversion including the hydrogen evolution reaction, oxygen evolution reaction, nitrogen reduction reaction, and carbon dioxide reduction reaction. In this Review, the recent progresses in terms of surface and interface engineering of Mox C-based electrocatalytic materials are summarized, including the increased number of active sites by decreasing the particle size or introducing porous or hierarchical structures and surface modification by introducing heteroatom(s), defects, carbon materials, and others electronic conductive species. Finally, the challenges and prospects for energy conversion on Mox C-based nanomaterials are discussed in terms of key performance parameters for the catalytic performance.

13.
Front Cell Neurosci ; 13: 310, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31379504

RESUMO

Background/Aims: Chronic cerebral hypoperfusion (CCH) is induced by chronic deficit of brain perfusion, contributes to a persistent or progressive cognitive dysfunction, which is characterized by diverse neuropathological manifestations. There are currently no effective medications available. White matter damage (WMD) and cortical neuron death may be caused by CCH, which are related to cognitive impairment, while the underlying molecular mechanisms remain unclear. In the study, a database of the transcriptome level was built to determine potential biomarkers in cortex of CCH. Methods: CCH was induced in male Sprague-Dawley rats by permanent occlusion of the bilateral common carotid arteries. Rats were randomly divided into three groups: Sham-operated group (n = 24), the 4th and 8th week of CCH groups (total = 56, n = 28 for each group). Cognitive function was evaluated using the Morris water maze task. WMD and neuron damage were detected using diffusion tensor imaging and histological analysis, respectively. Western blotting analysis of various markers was used to examine neuronal death. Whole-transcriptome microarray was performed to assess mRNA, circRNA, and lncRNA expression profiles at 4th and 8th weeks after CCH. Diversified bioinformatic tools were performed to analyze and predict the key biological processes and signaling pathways of differentially expressed RNAs and co-expressed potential target genes. Co-expression networks of mRNA-circRNA-miRNA and lncRNA-mRNA were constructed. Results: Compared to the sham group, cognitive impairment, disintegration of white matter, blood-brain barrier damage and neuron death were induced by CCH. Neuron death including apoptosis and necroptosis might occur in the cortex of CCH. We constructed the regulatory networks of whole-transcriptomic including differentially expressed mRNAs, circRNAs, and lncRNAs, and related biological functions and pathways involved in neurological disease, cell death and survival, energy and metabolism, et al. Our results also indicated that Cyr61 mRNA may play a role in the CCH-related cortical neuronal death. Conclusion: WMD and cortical neuronal death are worthy of attention in the pathogenesis of CCH. Additionally, the present results provide potential evidence at the whole-transcription level for CCH, offering candidate biomarkers and therapeutic targets.

14.
Artif Cells Nanomed Biotechnol ; 47(1): 3638-3648, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31456425

RESUMO

Aims: To explore the roles and regulatory mechanisms of the circular RNA (circRNA)-hsa-circ-0072309 in CAKI-1 and ACHN cells. Methods: CAKI-1 and ACHN cells were transfected with hsa-circ-0072309 overproduction vector (circRNA) and microRNA-100 (miR-100) mimic or the corresponding controls. Cell viability was detected with the CCK-8. The protein expression levels of p53, c-Myc, cleaved-caspase-3/9, matrix metalloproteinase (MMP)-2/9, vimentin, AKT, PI3K and mTOR were individually determined through western blot. qRT-PCR was used to examine the expressions of hsa-circ-0072309 and miR-100. The apoptotic rate and the migration or invasion rates were separately determined by the annexin v-FITC/PI with a flow cytometer and modified two-chamber migration assay or millicell hanging cell culture. Results: The hsa-circ-0072309 was poorly expressed in tumor tissue. Abundant hsa-circ-0072309 induced the inhibitions of cell proliferation, migration and invasion, as well as the PI3K/AKT and the mTOR cascades but enhancement of apoptosis. circRNA stimulated the down-regulation of miR-100, which was low-expressed in tumour tissue and whose overproduction abolished the impacts of circRNA on these elements mentioned above. Conclusion: The hsa-circ-0072309 played anti-tumour roles by targeting miR-100 by blocking the PI3K/AKT and mTOR cascades in the CAKI-1 and ACHN cell lines.


Assuntos
Carcinoma de Células Renais/patologia , Neoplasias Renais/patologia , MicroRNAs/genética , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Apoptose/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Regulação para Baixo , Ativação Enzimática/genética , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Invasividade Neoplásica/genética , Transdução de Sinais/genética
15.
Front Cell Neurosci ; 13: 351, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31456664

RESUMO

Hippocampal neuron death is a key factor in vascular dementia (VD) induced by chronic cerebral hypoperfusion (CCH). Dl-3-n-butylphthalide (NBP) is a multiple-effects drug. Therefore, the potential molecular mechanisms underlying CCH and its feasible treatment should be investigated. This study had two main purposes: first, to identify a potential biomarker in a rat model of CCH induced VD using antibody microarrays; and second, to explore the neuroprotective role of NBP at targeting the potential biomarker. Glial cell line-derived neurotrophic factor (GDNF)/GDNF family receptor alpha-1 (GFRα1)/receptor tyrosine kinase (Ret) signaling is altered in the hippocampus of CCH rats; however, NBP treatment improved cognitive function, protected against hippocampal neuron apoptosis via regulation of GDNF/GFRα1/Ret, and activated the phosphorylation AKT (p-AKT) and ERK1/2 (p-ERK1/2) signaling. We also found that 1 h oxygen-glucose deprivation (OGD) followed by 48 h reperfusion (R) in cultured hippocampal neurons led to downregulation of GDNF/GFRα1/Ret. NBP upregulated the signaling and increased neuronal survival. Ret inhibitor (NVP-AST487) inhibits Ret and downstream effectors, including p-AKT and p-ERK1/2. Additionally, both GDNF and GFRα1 expression are markedly inhibited in hippocampal neurons by coincubation with NVP-AST487, particularly under conditions of OGD/R. GDNF/GFRα1/Ret signaling and neuronal viability can be maintained by NBP, which activates p-AKT and p-ERK1/2, increases expression of Bcl-2, and decreases expression of Bax and cleaved caspase-3. The current study showed that GDNF/GFRα1/Ret signaling plays an essential role in the CCH induced VD. NBP was protective against hippocampal neuron apoptosis, and this was associated with regulation of GDNF/GFRα1/Ret and AKT/ERK1/2 signaling pathways, thus reducing cognitive impairment.

16.
Front Neurosci ; 13: 549, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31191236

RESUMO

Compensatory vascular mechanisms can restore cerebral blood flow (CBF) but fail to protect against chronic cerebral hypoperfusion (CCH)-mediated neuronal damage and cognitive impairment. Prostaglandin E1 (PGE1) is known as a vasodilator to protect against ischemic injury in animal models, but its protective role in CCH remains unclear. To determine the effect of PGE1 on cerebral hemodynamics and cognitive functions in CCH, bilateral common carotid artery occlusion (BCCAO) was used to mimic CCH in rats, which were subsequently intravenously injected with PGE1 daily for 2 weeks. Magnetic resonance imaging, immunofluorescence staining and Morris water maze (MWM) were used to evaluate CBF, angiogenesis, and cognitive functions, respectively. We found that PGE1 treatment significantly restored CBF by enhancing vertebral artery dilation. In addition, PGE1 treatment increased the number of microvascular endothelial cells and neuronal cells in the hippocampus, and decreased the numbers of astrocyte and apoptotic cells. In the MWM test, we further showed that the escape latency of CCH rats was significantly reduced after PGE1 treatment. Our results suggest that PGE1 ameliorates cognitive dysfunction in CCH rats by enhancing CBF recovery, sustaining angiogenesis, and reducing astrocyte activation and neuronal loss.

17.
Biomed Pharmacother ; 113: 108757, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30897537

RESUMO

Previous findings have demonstrated, in a rat model, that chronic cerebral hypoperfusion (CCH) decreases cortical cerebral blood flow (CBF) while Dl-3-n-Butylphthalide (DNB) accelerates the timely recovery of CBF. However, potential biomarkers, therapeutic targets, and underlying mechanisms for these processes are unclear. In this study, a solid-phase antibody microarray for simultaneously detecting multiple proteins was used to search cortex biotargets in CCH compared to a sham control group, and these results were further examined by biological functional analysis. After DNB treatment, western blot and immunostaining were used to verify candidate protein expression. Importantly, we identified seven proteins that may serve as novel biotargets contributing to CCH. The levels of Tie-2, CNTFRα, IL-4, IL-10, ITGAM, MDC, and TROY were uniquely altered in the CCH. The Tie-2 level was significantly decreased and identified in CCH 2 week (W), CCH 4 W and CCH 8 W. In addition, Ang-1 level and Ang-1/Ang-2 ratio were significantly decreased in CCH 2 W and CCH 4 W while Ang-2 level was increased in the CCH, whereas DNB treatment created the inverse effect to some extent. Moreover, the expression of VEGF and CD34 in the earlier stage of CCH and the diameters of bilateral vertebral arteries (VAs), were significantly enlarged by DNB treatment. Together, we found that the Ang-1/Ang-2/Tie-2 signaling axis was altered in the CCH rat cortex, and DNB treatment could timely regulate this angiopoietin/Tie signaling axis to promote neovascularization in early stages.


Assuntos
Benzofuranos/farmacologia , Córtex Cerebral/irrigação sanguínea , Circulação Cerebrovascular/efeitos dos fármacos , Neovascularização Fisiológica/efeitos dos fármacos , Angiopoietina-1/metabolismo , Angiopoietina-2/metabolismo , Animais , Western Blotting , Isquemia Encefálica/tratamento farmacológico , Córtex Cerebral/efeitos dos fármacos , Masculino , Análise Serial de Proteínas/métodos , Ratos , Ratos Sprague-Dawley , Receptor TIE-2/metabolismo , Transdução de Sinais/efeitos dos fármacos
18.
Neuroradiology ; 61(4): 451-459, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30725121

RESUMO

PURPOSE: The recommendation strength of the guidelines for mechanical thrombectomy among patients with large pre-treatment core infarct is weak. We evaluated the safety and outcome of endovascular treatment for acute ischemic stroke with diffusion-weighted imaging-Alberta Stroke Program Early Computed Tomography Score (DWI-ASPECTS) ≤ 5. METHODS: Data on acute ischemic stroke patients with DWI-ASPECTS ≤ 5 who underwent endovascular treatment within 6 h, or presented an arterial spin labeling-DWI (ASL-DWI) mismatch within 12 h, at our center were retrospectively collected. We report the clinical characteristics and outcome of every patient, and review the relevant literature. RESULTS: Among the 19 patients who were enrolled, all experienced successful reperfusion, and 10 achieved a favorable outcome (modified Rankin scale (mRS) ≤ 2). Two patients presented with symptomatic intracranial hemorrhage (sICH); both of them had a poor outcome (mRS > 2). CONCLUSION: Acute ischemic stroke patients with large DWI lesions caused by large vessel occlusion can achieve a favorable clinical outcome with endovascular treatment if recanalization is performed within 6 h, or after 6 h in case of an ASL-DWI mismatch.


Assuntos
Isquemia Encefálica/diagnóstico por imagem , Isquemia Encefálica/cirurgia , Imagem de Difusão por Ressonância Magnética/métodos , Procedimentos Endovasculares , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/cirurgia , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Marcadores de Spin , Fatores de Tempo , Resultado do Tratamento
19.
ACS Appl Mater Interfaces ; 11(11): 10818-10828, 2019 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-30785258

RESUMO

Extrinsic two-dimensional flux pinning centers, via graphene-encapsulated boron powder as precursors, have been introduced into MgB2 superconductors by means of in situ and diffusion sintering methods. Uniform graphene encapsulation of the boron powders was achieved by the hydrothermal method with highly dispersed graphene oxide as the precursor. The graphene coating layers induce remaining graphene layers and other defects acting as flux pinning centers in the matrix as well as improved connectivity in between grains. The increased critical current density ( Jc) is attributed to the enhanced flux pinning force and improved connectivity. Two-dimensional flux pinning centers provided by thin graphene layers and grain boundaries in MgB2 possess high flux pinning efficiency without suppressing the connectivity of the MgB2 superconductor.

20.
Nanomaterials (Basel) ; 9(2)2019 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-30717359

RESUMO

Two novel core-shell composites SiO2@PMDA-Si-Tb, SiO2@PMDA-Si-Tb-phen with SiO2 as the core and terbium organic complex as the shell, were successfully synthesized. The terbium ion was coordinated with organic ligand forming terbium organic complex in the shell layer. The bi-functional organosilane ((HOOC)2C6H2(CONH(CH2)3Si(OCH2CH3)3)2 (abbreviated as PMDA-Si) was used as the first ligand and phen as the second ligand. Furthermore, the silica-modified SiO2@PMDA-Si-Tb@SiO2 and SiO2@PMDA-Si-Tb-phen@SiO2 core-shell-shell composites were also synthesized by sol-gel chemical route. An amorphous silica shell was coated around the SiO2@PMDA-Si-Tb and SiO2@PMDA-Si-Tb-phen core-shell composites. The core-shell and core-shell-shell composites both exhibited excellent luminescence in solid state. The luminescence of core-shell-shell composites was stronger than that of core-shell composites. Meanwhile, an improved luminescence stability property for the core-shell-shell composites was found in the aqueous solution. The core-shell-shell composites exhibited bright luminescence, high stability, long lifetime, and good solubility, which may present potential applications in the bio-medical field.

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