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1.
J Mol Cell Cardiol ; 193: 1-10, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38789075

RESUMO

BACKGROUND: Hypothermic ischemia-reperfusion arrhythmia is a common complication of cardiothoracic surgery under cardiopulmonary bypass, but few studies have focused on this type of arrhythmia. Our prior study discovered reduced myocardial Cx43 protein levels may be linked to hypothermic reperfusion arrhythmias. However, more detailed molecular mechanism research is required. METHOD: The microRNA and mRNA expression levels in myocardial tissues were detected by real-time quantitative PCR (RT-qPCR). Besides, the occurrence of hypothermic reperfusion arrhythmias and changes in myocardial electrical conduction were assessed by electrocardiography and ventricular epicardial activation mapping. Furthermore, bioinformatics analysis, applying antagonists of miRNA, western blotting, immunohistochemistry, a dual luciferase assay, and pearson correlation analysis were performed to investigate the underlying molecular mechanisms. RESULTS: The expression level of novel-miR-17 was up-regulated in hypothermic ischemia-reperfusion myocardial tissues. Inhibition of novel-miR-17 upregulation ameliorated cardiomyocyte edema, reduced apoptosis, increased myocardial electrical conduction velocity, and shortened the duration of reperfusion arrhythmias. Mechanistic studies showed that novel-miR-17 reduced the expression of Cx43 by directly targeting Gja1 while mediating the activation of the PKC/c-Jun signaling pathway. CONCLUSION: Up-regulated novel-miR-17 is a newly discovered pro-arrhythmic microRNA that may serve as a potential therapeutic target and biomarker for hypothermic reperfusion arrhythmias.


Assuntos
Arritmias Cardíacas , Conexina 43 , MicroRNAs , Proteína Quinase C , Transdução de Sinais , Animais , Humanos , Masculino , Ratos , Apoptose/genética , Arritmias Cardíacas/metabolismo , Arritmias Cardíacas/genética , Arritmias Cardíacas/etiologia , Arritmias Cardíacas/patologia , Conexina 43/metabolismo , Conexina 43/genética , MicroRNAs/genética , MicroRNAs/metabolismo , Traumatismo por Reperfusão Miocárdica/metabolismo , Traumatismo por Reperfusão Miocárdica/genética , Traumatismo por Reperfusão Miocárdica/patologia , Traumatismo por Reperfusão Miocárdica/etiologia , Miocárdio/metabolismo , Miocárdio/patologia , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Proteína Quinase C/metabolismo , Proteína Quinase C/genética , Proteínas Proto-Oncogênicas c-jun/metabolismo , Regulação para Cima
2.
Small ; 20(12): e2305778, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37948356

RESUMO

The fast development of Internet of Things and the rapid advent of next-generation versatile wearable electronics require cost-effective and highly-efficient electroactive materials for flexible electrochemical energy storage devices. Among various electroactive materials, binder-free nanostructured arrays have attracted widespread attention. Featured with growing on a conductive and flexible substrate without using inactive and insulating binders, binder-free 3D nanoarray electrodes facilitate fast electron/ion transportation and rapid reaction kinetics with more exposed active sites, maintain structure integrity of electrodes even under bending or twisted conditions, readily release generated joule heat during charge/discharge cycles and achieve enhanced gravimetric capacity of the whole device. Binder-free metal-organic framework (MOF) nanoarrays and/or MOF-derived nanoarrays with high surface area and unique porous structure have emerged with great potential in energy storage field and been extensively exploited in recent years. In this review, common substrates used for binder-free nanoarrays are compared and discussed. Various MOF-based and MOF-derived nanoarrays, including metal oxides, sulfides, selenides, nitrides, phosphides and nitrogen-doped carbons, are surveyed and their electrochemical performance along with their applications in flexible energy storage are analyzed and overviewed. In addition, key technical issues and outlooks on future development of MOF-based and MOF-derived nanoarrays toward flexible energy storage are also offered.

3.
Angew Chem Int Ed Engl ; 63(18): e202402327, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38467561

RESUMO

Metallic zinc is a promising anode material for rechargeable aqueous multivalent metal-ion batteries due to its high capacity and low cost. However, the practical use is always beset by severe dendrite growth and parasitic side reactions occurring at anode/electrolyte interface. Here we demonstrate dynamic molecular interphases caused by trace dual electrolyte additives of D-mannose and sodium lignosulfonate for ultralong-lifespan and dendrite-free zinc anode. Triggered by plating and stripping electric fields, the D-mannose and lignosulfonate species are alternately and reversibly (de-)adsorbed on Zn metal, respectively, to accelerate Zn2+ transportation for uniform Zn nucleation and deposition and inhibit side reactions for high Coulombic efficiency. As a result, Zn anode in such dual-additive electrolyte exhibits highly reversible and dendrite-free Zn stripping/plating behaviors for >6400 hours at 1 mA cm-2, which enables long-term cycling stability of Zn||ZnxMnO2 full cell for more than 2000 cycles.

4.
Neuroimage ; 269: 119923, 2023 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-36739101

RESUMO

BACKGROUND: Microstructural changes in deep gray matter (DGM) nuclei are related to physiological behavior, cognition, and memory. Therefore, it is critical to study age-dependent trajectories of biomarkers in DGM nuclei for understanding brain development and aging, as well as predicting cognitive or neurodegenerative diseases. OBJECTIVES: We aimed to (1) characterize age-dependent trajectories of mean susceptibility, adjusted volume, and total iron content simultaneously in DGM nuclei using quantitative susceptibility mapping (QSM); (2) examine potential contributions of sex related effects to the different age-dependence trajectories of volume and iron deposition; and (3) evaluate the ability of brain age prediction by combining mean magnetic susceptibility and volume of DGM nuclei. METHODS: Magnetic susceptibilities and volumetric values of DGM nuclei were obtained from 220 healthy participants (aged 10-70 years) scanned on a 3T MRI system. Regions of interest (ROIs) were drawn manually on the QSM images. Univariate regression analysis between age and each of the MRI measurements in a single ROI was performed. Pearson correlation coefficients were calculated between magnetic susceptibility and adjusted volume in a single ROI. The statistical significance of sex differences in age-dependent trajectories of magnetic susceptibilities and adjusted volumes were determined using one-way ANCOVA. Multiple regression analysis was used to evaluate the ability to estimate brain age using a combination of the mean susceptibilities and adjusted volumes in multiple DGM nuclei. RESULTS: Mean susceptibility and total iron content increased linearly, quadratically, or exponentially with age in all six DGM nuclei. Negative linear correlation was observed between adjusted volume and age in the head of the caudate nucleus (CN; R2 = 0.196, p < 0.001). Quadratic relationships were found between adjusted volume and age in the putamen (PUT; R2 = 0.335, p < 0.001), globus pallidus (GP; R2 = 0.062, p = 0.001), and dentate nucleus (DN; R2 = 0.077, p < 0.001). Males had higher mean magnetic susceptibility than females in the PUT (p = 0.001), red nucleus (RN; p = 0.002), and substantia nigra (SN; p < 0.001). Adjusted volumes of the CN (p < 0.001), PUT (p = 0.030), GP (p = 0.007), SN (p = 0.021), and DN (p < 0.001) were higher in females than those in males throughout the entire age range (10-70 years old). The total iron content of females was higher than that of males in the CN (p < 0.001), but lower than that of males in the PUT (p = 0.014) and RN (p = 0.043) throughout the entire age range (10-70 years old). Multiple regression analyses revealed that the combination of the mean susceptibility value of the PUT, and the volumes of the CN and PUT had the strongest associations with brain age (R2 = 0.586). CONCLUSIONS: QSM can be used to simultaneously investigate age- and sex- dependent changes in magnetic susceptibility and volume of DGM nuclei, thus enabling a comprehensive understanding of the developmental trajectories of iron accumulation and volume in DGM nuclei during brain development and aging.


Assuntos
Encéfalo , Substância Cinzenta , Humanos , Masculino , Feminino , Criança , Adolescente , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Idoso , Imageamento por Ressonância Magnética/métodos , Envelhecimento , Mapeamento Encefálico/métodos , Ferro
5.
J Magn Reson Imaging ; 58(2): 581-590, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-36594513

RESUMO

BACKGROUND: Deep brain stimulation (DBS) of the subthalamic nucleus (STN) improves motor deficits in advanced Parkinson's disease (PD) patients, but the degree of motor improvement varies across individuals. PD pathology involves the changes of iron spatial distribution in the deep gray matter nuclei. PURPOSE: To explore the relationship between the iron spatial distribution and motor improvement among PD patients who underwent STN-DBS surgery in three regions: substantia nigra (SN), STN, and dentate nucleus (DN). STUDY TYPE: Prospective. SUBJECTS: Forty PD patients (49.7 ± 8.8 years, 22 males/18 females) who underwent bilateral STN-DBS. FIELD STRENGTH/SEQUENCE: A 3 T preoperative three-dimensional spoiled bipolar-readout multi-echo gradient recalled echo and two-dimensional fast spin echo sequences. ASSESSMENT: Movement Disorder Society-sponsored revision of the Unified Parkinson's Disease Rating Scale part III (MDS-UPDRS III) scores were assessed 2-3 days before and 6 months after STN-DBS. The first- and second-order texture features in regions of interest were measured on susceptibility maps. STATISTICAL TESTS: Intraclass correlation coefficient was used to determine the consistency of the region of interest volumes delineated by the two raters. Pearson or Spearman's correlation coefficients were used to assess the relationship between motor improvement after DBS and texture features. A P-value <0.05 was considered statistically significant. RESULTS: MDS-UPDRS III scores were reduced by 59.9% after STN-DBS in 40 PD patients. Motor improvement correlated with second-order texture parameters in the SN including angular second moment (r = -0.449), correlation (rho = 0.326), sum of squares (r = 0.402), sum of entropy (rho = 0.421), and entropy (r = 0.410). Additionally, DBS outcome negatively correlated with mean susceptibility values in the DN (r = -0.400). DATA CONCLUSION: PD patients with a more homogeneous iron distribution throughout the SN or a higher iron concentration in the DN responded worse to STN-DBS. LEVEL OF EVIDENCE: 2 TECHNICAL EFFICACY: Stage 1.


Assuntos
Estimulação Encefálica Profunda , Doença de Parkinson , Masculino , Feminino , Humanos , Doença de Parkinson/diagnóstico por imagem , Doença de Parkinson/terapia , Resultado do Tratamento , Estudos Prospectivos , Substância Cinzenta/diagnóstico por imagem
6.
Zhongguo Dang Dai Er Ke Za Zhi ; 25(9): 966-970, 2023.
Artigo em Chinês | MEDLINE | ID: mdl-37718404

RESUMO

OBJECTIVES: To study the relationship between coronavirus disease 2019 (COVID-19) vaccination and the risk of immune thrombocytopenia (ITP). METHODS: A retrospective analysis was conducted on children aged 3-17 years with newly diagnosed ITP who were hospitalized in Children's Hospital Affiliated to Zhengzhou University from November 2021 to December 2022. Clinical data and COVID-19 vaccination status were compared among three groups: ITP patients vaccinated within 12 weeks before onset, vaccinated more than 12 weeks before onset, and unvaccinated. Changes in serum immunoglobulin and complement levels were analyzed among five groups: ITP patients vaccinated <4 weeks before onset, 4-<8 weeks before onset, 8-<12 weeks before onset, ≥12 weeks before onset, and unvaccinated. A case-control design was used to estimate the risk of ITP: 387 children aged 3-17 years with fractures hospitalized during the same period in the emergency department of the hospital were selected as the control group, and the exposure to COVID-19 vaccination within 12, 8, and 4 weeks before onset in ITP children was compared to estimate the risk of ITP. RESULTS: Among 129 ITP children, there were no statistically significant differences in age, gender, rate of preceding infections, absolute platelet count at initial diagnosis, absolute lymphocyte count at initial diagnosis, bleeding score, positive anti-nuclear antibody rate, absolute platelet count after 4 days of treatment, recurrence rate, and proportion of patients with disease duration ≥3 months among the three groups vaccinated within 12 weeks before onset, vaccinated more than 12 weeks before onset, and unvaccinated (P>0.05). There was a statistically significant difference in serum immunoglobulin G, immunoglobulin A, and complement component 3 levels among the groups vaccinated <4 weeks, 4-<8 weeks, 8-<12 weeks, and ≥12 weeks before onset, and unvaccinated (P<0.05). The risk estimation results showed that COVID-19 vaccination within 12 weeks, 8 weeks, and 4 weeks before onset did not increase the risk of ITP (P>0.05). CONCLUSIONS: COVID-19 vaccination does not increase the risk of ITP.

7.
Phys Chem Chem Phys ; 24(9): 5522-5528, 2022 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-35171974

RESUMO

Interactions between quantum systems and their environments may always result in inevitable decoherence. Isolation of the quantum system from the undesired environmental noise is a great challenge for ideal quantum information processing. Herein, based on a parallelly shaped control-target molecular nanomagnet structure, we report a novel strategy which decouples the target molecular device from its surrounding conduction baths. By tuning the level differences between the control and target orbitals through external gate voltages, one manipulates both, neither or only the target subsystem to contribute to the quantum transport in sequence, corresponding to an "on-off-on" behavior in the linear conductance. In the off window, a local transport circulation develops, preventing the target device from being disturbed by the itinerant electrons. This finding provides a prospective method for confining integrated quantum devices with high intrinsic fidelity, remarkable tunability, and universal suitability.

8.
Acta Radiol ; 62(2): 281-288, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32551871

RESUMO

BACKGROUND: Computed tomography perfusion (CTP) can provide information on blood perfusion as a reliable marker of tumor response to therapy. PURPOSE: To assess the role of volume CTP (vCTP) parameters in predicting treatment response to concurrent chemoradiotherapy (CCRT) for cervical cancer. MATERIAL AND METHODS: Thirty-three patients with cervical cancer underwent vCTP. Three CTP parameters of cervical cancer-including arterial flow (AF), blood volume (BV), and permeability surface (PS)-were measured in two different ways: the region of interest incorporating the "local hot" with the highest enhancement and "cold spot" with the lowest enhancement; and "whole-tumor" measurements. The patients were divided into non-residual and residual tumor groups according to the short-term response to treatment. The clinical and perfusion parameters were compared between the two groups. RESULTS: There was no significant difference in age, body mass index, FIGO stage, pathological grade, or pretreatment tumor size between the two groups (P > 0.05). The non-residual tumor group had higher pretreatment AF in high-perfusion and low-perfusion subregions than the residual tumor group (P <0.05), but the AF in whole-tumor regions was not different between the two groups (P > 0.05). There were no differences in BV and PS between the two groups (P > 0.05). The diagnostic potency of AF in the low-perfusion subregion was higher than that in the high-perfusion subregion. CONCLUSION: vCTP parameters are valuable for the prediction of short-term effects. The AF in the low-perfusion subregion was a more effective index for predicting treatment response to CCRT of cervical cancer.


Assuntos
Quimiorradioterapia/métodos , Tomografia Computadorizada de Feixe Cônico/métodos , Neoplasias do Colo do Útero/diagnóstico por imagem , Neoplasias do Colo do Útero/terapia , Adulto , Idoso , Colo do Útero/diagnóstico por imagem , Colo do Útero/efeitos dos fármacos , Colo do Útero/efeitos da radiação , Feminino , Humanos , Pessoa de Meia-Idade , Imagem de Perfusão , Valor Preditivo dos Testes , Estudos Prospectivos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Resultado do Tratamento
9.
J Asian Nat Prod Res ; 23(2): 176-188, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31888388

RESUMO

In this study, twenty-four oleanolic acid (OA) derivatives were rationally designed based on molecule docking studies and their VEGFR-2 inhibitory activities were tested by Homogeneous time-resolved fluorescence (HTRF) method in vitro. All of the synthesized compounds were identified as new compounds, and the structures of these compounds were determined by 1H-NMR and ESI-MS. In the screening for VEGFR-2 inhibitors, compounds I6 and I7 exhibited excellent inhibitory effect. The results indicated that insertion of phenylurea group with a linker at position C-28 of OA can increase the activity against VEGFR-2 significantly. [Formula: see text].


Assuntos
Ácido Oleanólico , Proliferação de Células , Desenho de Fármacos , Simulação de Acoplamento Molecular , Estrutura Molecular , Ácido Oleanólico/farmacologia , Relação Estrutura-Atividade , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo
10.
Mov Disord ; 35(10): 1787-1795, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32681698

RESUMO

BACKGROUND: Currently, no study has evaluated metal accumulation in the brains of patients with Wilson's disease by using quantitative susceptibility mapping at 3T MRI. The objectives of this study were to qualitatively and quantitatively evaluate changes in magnetic susceptibility and R2* maps in deep gray matter nuclei to discriminate Wilson's disease patients from healthy controls and to evaluate their sensitivities in diagnosing Wilson's disease. METHODS: Magnetic susceptibility and R2* maps and conventional T1-weighted, T2-weighted, and T2-weighted fluid-attenuated inversion recovery images were obtained from 17 Wilson's disease patients and 14 age-matched healthy controls on a 3T MRI scanner. Differences between Wilson's disease and healthy control groups in susceptibility and R2* values in multiple deep nuclei were evaluated using a Mann-Whitney U test and receiver operating characteristic curves. The correlations of susceptibility and R2* values with Unified Wilson's Disease Rating Scale score were also performed. RESULTS: Magnetic susceptibility and R2* can effectively distinguish different types of signal abnormalities. Magnetic susceptibility and R2* values in multiple deep nuclei of Wilson's disease patients were significantly higher than those in healthy controls. Magnetic susceptibility value in the substantia nigra had the highest area under the curve (0.888). There were positive correlations of the Unified Wilson's Disease Rating Scale score with susceptibility values in the caudate nucleus (r = 0.757, P = 0.011), putamen (r = 0.679, P = 0.031), and red nucleus (r = 0.638, P = 0.047), as well as R2* values in the caudate nucleus (r = 0.754, P = 0.012). CONCLUSIONS: Quantitative susceptibility mapping at 3T could be a useful tool to evaluate metal accumulation in deep gray matter nuclei of Wilson's disease patients. © 2020 International Parkinson and Movement Disorder Society.


Assuntos
Degeneração Hepatolenticular , Encéfalo/diagnóstico por imagem , Mapeamento Encefálico , Degeneração Hepatolenticular/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Substância Negra
11.
Clin Exp Pharmacol Physiol ; 47(3): 439-448, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31587336

RESUMO

Dysregulation of long non-coding RNA papillary thyroid carcinoma susceptibility candidate 3 (lncRNA PTCSC3) has been found to correlate with various types of cancers. Quantitative RT-PCR showed a down-regulation of PTCSC3 in cervical cancer tissues compared with normal cervical tissues. The present study aimed to investigate the role of lncRNA PTCSC3 in cervical cancer and the underlying mechanisms. PTCSC3 was overexpressed in cervical cancer cell lines C-33A and Hela by transfection with pcDNA3.1-lncRNA PTCSC3 expressing plasmid. Overexpression of lncRNA PTCSC3 inhibited cell proliferation, induced cell cycle arrest, and suppressed cell invasion and migration using CCK8 assay, flow cytometry, Transwell assay and wound healing examination, respectively. Western blotting analysis showed that PTCSC3 overexpression decreased the expression of cyclinD1, matrix metalloproteinases 9 (MMP9), N-cadherin and ß-catenin and increased E-cadherin expression. Further, PTCSC3 negatively regulated miR-574-5p expression and dual-luciferase assay verified the binding activity between miR-574-5p and lncRNA PTCSC3. Enforced up-regulation of miR-574-5p abolished the inhibitory effect of lncRNA PTCSC3 on cervical cancer cell proliferation, invasiveness and mobility. Taken together, lncRNA PTCSC3 inhibited cell growth and metastasis via sponging miR-574-5p in cervical cancer. Therefore, we demonstrate the tumour-suppressive function of lncRNA PTCSC3 in cervical cancer and suggest that PTCSC3 is a potential therapeutic target for cervical cancer.


Assuntos
Movimento Celular/fisiologia , Proliferação de Células/fisiologia , MicroRNAs/biossíntese , RNA não Traduzido/biossíntese , Neoplasias do Colo do Útero/metabolismo , Feminino , Células HeLa , Humanos , MicroRNAs/antagonistas & inibidores , Invasividade Neoplásica/patologia , Invasividade Neoplásica/prevenção & controle , Células Tumorais Cultivadas , Neoplasias do Colo do Útero/patologia , Neoplasias do Colo do Útero/prevenção & controle
12.
Electrophoresis ; 40(12-13): 1699-1707, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30977901

RESUMO

Point-of-care detection for pathogen is of critical need for wide epidemic warning and medical diagnosis. In this work, we have designed and developed a fully portable and integrated microchip based real-time polymerase chain reaction machine for rapid pathogen detection. The instrument consists of three functional components including heating, optical, and electrical modules, which are integrated into a portable compact box. The microchip is consumable material replaceable to meet various detection needs. Consequently, we demonstrated the outstanding performance of this portable machine for rapid detection of Salmonella and Escherichia coli O157:H7 with the advantage of time-saving (∼25 min), less samples consumption, portability, and user-friendly operation.


Assuntos
DNA Bacteriano , Tipagem Molecular , Testes Imediatos , Reação em Cadeia da Polimerase em Tempo Real , DNA Bacteriano/análise , DNA Bacteriano/genética , DNA Bacteriano/isolamento & purificação , Desenho de Equipamento , Escherichia coli O157/genética , Escherichia coli O157/isolamento & purificação , Células HeLa , Humanos , Tipagem Molecular/instrumentação , Tipagem Molecular/métodos , Reação em Cadeia da Polimerase em Tempo Real/instrumentação , Reação em Cadeia da Polimerase em Tempo Real/métodos , Salmonella/genética , Salmonella/isolamento & purificação
13.
Phys Rev Lett ; 121(2): 024301, 2018 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-30085689

RESUMO

Topological characteristics of energy bands, such as Dirac and Weyl nodes, have attracted substantial interest in condensed matter systems as well as in classical wave systems. Among these energy bands, the type-II Dirac point is a nodal degeneracy with tilted conical dispersion, leading to a peculiar crossing dispersion in the constant-energy plane. Such nodal points have recently been found in electronic materials. The analogous topological feature in photonic systems remains a theoretical curiosity, with experimental realization expected to be challenging. Here, we experimentally realize the type-II Dirac point using a planar metasurface architecture, where the band degeneracy point is protected by the underlying mirror symmetry of the metasurface. Gapless edge modes are found and measured at the boundary between the different domains of the symmetry-broken metasurface. Our Letter shows that metasurfaces are simple and practical platforms for realizing electromagnetic type-II Dirac points, and their planar structure is a distinct advantage that facilitates applications in two-dimensional topological photonics.

14.
Chemphyschem ; 19(16): 2052-2057, 2018 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-29575720

RESUMO

A new kind of fast near-infrared (NIR) light-responsive shape-memory polymer composites was prepared by introducing polydopamine particles (PDAPs) into commercial shape-memory polyurethane (SMPU). The toughness and strength of the polydopamine-particle-filled polyurethane composites (SMPU-PDAPs) were significantly enhanced with the addition of PDAPs due to the strong interface interaction between PDAPs and polyurethane segments. Owing to the outstanding photothermal effect of PDAPs, the composites exhibit a rapid light-responsive shape-memory process in 60 s with a PDAPs content of 0.01 wt%. Due to the excellent dispersion and convenient preparation method, PDAPs have great potential to be used as high-efficiency and environmentally friendly fillers to obtain novel photoactive functional polymer composites.

15.
Cell Biol Int ; 42(9): 1124-1131, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29660204

RESUMO

The aim of this study was to investigate the underlying mechanisms of hypoxia-induced apoptosis of GC-2spd (GC-2) cells. The GC-2 cells were treated with or without hypoxia for 12, 24, 48, and 72 h. Apoptosis of GC-2 cells was detected using TUNEL and flow cytometry. Fluorescence microscopic was used to observe the autophagy of GC-2 cells. Hypoxia-inducible factor-1alpha (HIF-1α), apoptosis-related protein and marker protein of autophagy levels were measured by Western blotting. Hypoxia induced apoptosis and autophagy of GC-2 cells, and increased expression of HIF-1α, LC3-II, Beclin-1, and pro-apoptotic protein, but reduced p62 and anti-apoptotic protein level. Meanwhile, hypoxia-induced HIF-1α mediated expression of apoptosis and autophagy-related protein in GC-2 cell. Furthermore, autophagy regulated hypoxia-induced apoptosis of GC-2 cell. Our data suggest that hypoxia induces apoptosis of GC-2 cell by activation of autophagy involving activation of the apoptosis signaling pathway under the hypoxic condition.


Assuntos
Hipóxia Celular/fisiologia , Espermatócitos/citologia , Espermatócitos/metabolismo , Animais , Apoptose/fisiologia , Autofagia/fisiologia , Proteína Beclina-1/metabolismo , Western Blotting , Linhagem Celular , Linhagem Celular Tumoral , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Masculino , Camundongos , Proteínas Associadas aos Microtúbulos/metabolismo , Transdução de Sinais
16.
Phys Chem Chem Phys ; 20(21): 14504-14512, 2018 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-29766174

RESUMO

Active catalysts for nitrogen fixation (N2-fixation) have been widely pursued through constant efforts for industrial applications. Here, we report a family of catalysts, MXenes (M2X: M = Mo, Ta, Ti, and W; X = C and N), for application in N2-fixation based on density functional theory calculations. We find that the catalytic performance of MXenes strongly depends on the reaction energy in each reaction step. More exothermic steps lead to higher catalytic performance in the course of N2-fixation. We show that the reaction energy in N2-fixation is strongly affected by the charge transfer: (1) if N atoms gain more electrons in a step, the reaction is exothermic with a larger reaction energy; (2) if N atoms lose electrons in a step, the reaction is endothermic in general. We further show that Mo2C and W2C are highly active for N2-fixation due to their exothermic reactions and strong charge transfer, which may be applicable in the chemical-engineering industry.

17.
Zhongguo Yi Liao Qi Xie Za Zhi ; 42(3): 176-179, 2018 May 30.
Artigo em Chinês | MEDLINE | ID: mdl-29885122

RESUMO

On account of the problem that traditional C-arm X-ray apparatus cannot provide precise route guidance for minimally invasive surgeries, we designed and developed a laser positioning and navigation system based on C-arm X-ray apparatus, which can achieve precise positioning function and reduce the exposure of doctors and patients to radiation in minimally invasive surgeries under the linear guidance of a laser beam. Furthermore, this system can enhance the refinement level of surgical operation in minimally invasive surgeries.


Assuntos
Procedimentos Cirúrgicos Minimamente Invasivos , Radiografia , Tomografia Computadorizada por Raios X , Tomografia Computadorizada de Feixe Cônico , Humanos , Cirurgia Assistida por Computador , Raios X
18.
J Sep Sci ; 40(11): 2506-2514, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28436147

RESUMO

A novel facile method for the detection of the phosphodiesterase type 5 enzyme inhibitors added illegally into health products was established using thin-layer chromatography and surface enhanced Raman spectroscopy combined with BP neural network. When the detection conditions were optimized in detail, a repetitive adding procedure of silver colloids with the total amount keeping constant was used to improve the enhancement effect of surface enhanced Raman spectroscopy. According to the main Raman peaks and the retention factor of analyte, the data predictive model was established. Under the optimized experimental conditions, this method was successful to apply to detect the artificially produced model samples, and the limit of detection less than 5 mg/kg was obtained. Based on the excellent sensitivity of this method, the real samples have been detected accurately and the detection results were confirmed by high-performance liquid chromatography. In addition, the developed method was suitable for the detection of other adulterants, especially those that have similar chromatographic or spectroscopic behaviors.


Assuntos
Cromatografia em Camada Fina , Contaminação de Medicamentos , Redes Neurais de Computação , Inibidores da Fosfodiesterase 5/análise , Análise Espectral Raman , Coloides , Prata
19.
Sensors (Basel) ; 17(6)2017 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-28561748

RESUMO

Er3+/Yb3+ codoped tellurite-zinc-niobium (TZNb) glass was prepared by the melt-quenching method and used for the construction of a point all-fiber temperature sensor. The glass thermal stability and network structural properties were studied by differential thermal analysis and Raman spectrum, respectively. High glass transition temperature is beneficial to widen the working temperature range. The dependence of fluorescence intensity ratio (FIR) of green upconversion emissions on the surrounding temperature from 276 to 363 K was experimentally investigated and the maximum temperature sensitivity is 95 × 10-4 K-1 at 363 K. Strong green upconversion emission, broad temperature measurement range and high sensitivity indicate this point temperature sensor is a promising optical device for application on optical temperature sensing.

20.
J Cell Mol Med ; 20(3): 459-70, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26647902

RESUMO

Inflammation plays a key role in pressure overload-induced cardiac hypertrophy and heart failure, but the mechanisms have not been fully elucidated. High-mobility group box 1 (HMGB1), which is increased in myocardium under pressure overload, may be involved in pressure overload-induced cardiac injury. The objectives of this study are to determine the role of HMGB1 in cardiac hypertrophy and cardiac dysfunction under pressure overload. Pressure overload was imposed on the heart of male wild-type mice by transverse aortic constriction (TAC), while recombinant HMGB1, HMGB1 box A (a competitive antagonist of HMGB1) or PBS was injected into the LV wall. Moreover, cardiac myocytes were cultured and given sustained mechanical stress. Transthoracic echocardiography was performed after the operation and sections for histological analyses were generated from paraffin-embedded hearts. Relevant proteins and genes were detected. Cardiac HMGB1 expression was increased after TAC, which was accompanied by its translocation from nucleus to both cytoplasm and intercellular space. Exogenous HMGB1 aggravated TAC-induced cardiac hypertrophy and cardiac dysfunction, as demonstrated by echocardiographic analyses, histological analyses and foetal cardiac genes detection. Nevertheless, the aforementioned pathological change induced by TAC could partially be reversed by HMGB1 inhibition. Consistent with the in vivo observations, mechanical stress evoked the release and synthesis of HMGB1 in cultured cardiac myocytes. This study indicates that the activated and up-regulated HMGB1 in myocardium, which might partially be derived from cardiac myocytes under pressure overload, may be of crucial importance in pressure overload-induced cardiac hypertrophy and cardiac dysfunction.


Assuntos
Cardiomegalia/metabolismo , Proteína HMGB1/fisiologia , Insuficiência Cardíaca/metabolismo , Hipertensão/metabolismo , Animais , Cardiomegalia/etiologia , Cardiomegalia/fisiopatologia , Células Cultivadas , Insuficiência Cardíaca/etiologia , Insuficiência Cardíaca/fisiopatologia , Hipertensão/complicações , Hipertensão/fisiopatologia , Masculino , Camundongos Endogâmicos C57BL , Miocárdio/metabolismo , Miocárdio/patologia , Miócitos Cardíacos/fisiologia , Transporte Proteico , Ratos , Estresse Fisiológico , Disfunção Ventricular Esquerda/etiologia , Disfunção Ventricular Esquerda/metabolismo , Disfunção Ventricular Esquerda/fisiopatologia
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