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Recent interest has surged in using heterogeneous carriers to boost synergistic photocatalysis for organic transformations. Heterogeneous catalysts not only facilitate synergistic enhancement of distinct catalytic centers compared to their homogeneous counterparts, but also allow for the easy recovery and reuse of catalysts. This mini-review summarizes recent advancements in developing heterogeneous carriers, including metal-organic frameworks, covalent-organic frameworks, porous organic polymers, and others, for synergistic catalytic reactions. The advantages of porous materials in heterogeneous catalysis originate from their ability to provide a high surface area, facilitate enhanced mass transport, offer a tunable chemical structure, ensure the stability of active species, and enable easy recovery and reuse of catalysts. Both photosensitizers and catalysts can be intricately incorporated into suitable porous carriers to create heterogeneous dual photocatalysts for organic transformations. Notably, experimental evidence from reported cases has shown that the catalytic efficacy of heterogeneous catalysts often surpasses that of their homogeneous analogues. This enhanced performance is attributed to the proximity and confinement effects provided by the porous nature of the carriers. It is expected that porous carriers will provide a versatile platform for integrating diverse catalysts, thus exhibiting superior performance across a range of organic transformations and appealing prospect for industrial applications.
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BACKGROUND: The purpose of this study was to investigate the predictive value of the 5-factor modified frailty index (mFI-5) for postoperative mortality, delirium and pneumonia in patients over 65 years of age undergoing elective lung cancer surgery. METHODS: Data were collected from a single-center retrospective cohort study conducted in a general tertiary hospital from January 2017 to August 2019. In total, the study included 1372 elderly patients aged over 65 who underwent elective lung cancer surgery. They were divided into frail group (mFI-5, 2-5), prefrail group (mFI-5, 1) and robust group (mFI-5, 0) on the basis of mFI-5 classification. The primary outcome was postoperative 1-year all-cause mortality. Secondary outcomes were postoperative pneumonia and postoperative delirium. RESULTS: Frailty group had the highest incidence of postoperative delirium (frailty 31.2% versus prefrailty 1.6% versus robust 1.5%, p < 0.001), postoperative pneumonia (frailty 23.5% versus prefrailty 7.2% versus robust 7.7%, p < 0.001), and postoperative 1-year mortality (frailty 7.0% versus prefrailty 2.2% versus robust 1.9%. p < 0.001). Frail patients have significantly longer length of hospitalization than those in the robust group and prefrail patients (p < 0.001). Multivariate analysis showed a clear link between frailty and increased risk of postoperative delirium (aOR 2.775, 95% CI 1.776-5.417, p < 0.001), postoperative pneumonia (aOR 3.291, 95% CI 2.169-4.993, p < 0.001) and postoperative 1-year mortality (aOR 3.364, 95% CI, 1.516-7.464, p = 0.003). CONCLUSIONS: mFI-5 has potential clinical utility in predicting postoperative death, delirium and pneumonia incidence in elderly patients undergoing radical lung cancer surgery. Frailty screening of patients (mFI-5) may provide benefits in risk stratification, targeted intervention efforts, and assist physicians in clinical decision-making.
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Porous organic polymers (POPs) have emerged as a novel class of porous materials that are synthesized by the polymerization of various organic monomers with different geometries and topologies. The molecular tunability of organic building blocks allows the incorporation of functional units for photocatalytic organic transformations. Here, we report the synthesis of two POP-based photocatalysts via homopolymerization of vinyl-functionalized diaryl dihydrophenazine (DADHP) monomer (POP1) and copolymerization of vinyl-functionalized DADHP and 2,2'-bipyridine monomers (POP2). The fluorescence lifetimes of DADHP units in the POPs significantly increased, resulting in enhanced photocatalytic performances over homogeneous controls. POP1 is highly effective in catalysing visible-light-driven C-N bond forming cross-coupling reactions. Upon coordination with Ni2+ ions, POP2-Ni shows strong synergy between photocatalytic and Ni catalytic cycles due to the confinement effect within the POP framework, leading to high efficiency in energy, electron, and organic radical transfer. POP2-Ni displays excellent activity in catalysing C-P bond forming reactions between diarylphosphine oxides and aryl iodides. They increased the photocatalytic activities by more than 30-fold in C-N and C-P cross-coupling reactions. These POP catalysts were readily recovered via centrifugal separation and reused in six catalytic cycles without loss of activities. Thus, photosensitizer-based POPs provide a promising platform for heterogeneous photocatalytic organic transformations.
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One of the most important tasks in remote sensing image analysis is remote sensing image Change Detection (CD), and CD is the key to helping people obtain more accurate information about changes on the Earth's surface. A Multi-Attention Guided Feature Fusion Network (MAFF-Net) for CD tasks has been designed. The network enhances feature extraction and feature fusion by building different blocks. First, a Feature Enhancement Module (FEM) is proposed. The FEM introduces Coordinate Attention (CA). The CA block embeds the position information into the channel attention to obtain the accurate position information and channel relationships of the remote sensing images. An updated feature map is obtained by using an element-wise summation of the input of the FEM and the output of the CA. The FEM enhances the feature representation in the network. Then, an attention-based Feature Fusion Module (FFM) is designed. It changes the previous idea of layer-by-layer fusion and chooses cross-layer aggregation. The FFM is to compensate for some semantic information missing as the number of layers increases. FFM plays an important role in the communication of feature maps at different scales. To further refine the feature representation, a Refinement Residual Block (RRB) is proposed. The RRB changes the number of channels of the aggregated features and uses convolutional blocks to further refine the feature representation. Compared with all compared methods, MAFF-Net improves the F1-Score scores by 4.9%, 3.2%, and 1.7% on three publicly available benchmark datasets, the CDD, LEVIR-CD, and WHU-CD datasets, respectively. The experimental results show that MAFF-Net achieves state-of-the-art (SOTA) CD performance on these three challenging datasets.
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Redes Neurais de Computação , Tecnologia de Sensoriamento Remoto , Humanos , Processamento de Imagem Assistida por Computador , Fator de Transcrição MafF , Proteínas Nucleares , SemânticaRESUMO
Cracks are the most significant pre-disaster of a road, and are also important indicators for evaluating the damage level of a road. At present, road crack detection mainly depends on manual detection and road detection vehicles, with which the safety of detection workers is not guaranteed and the detection efficiency is low. A road detection vehicle can speed up the efficiency to a certain extent, but the automation level is low and it is easy to block the traffic. Unmanned Aerial Vehicles (UAV) have the characteristics of low energy consumption and easy control. If UAV technology can be applied to road crack detection, it will greatly improve the detection efficiency and produce huge economic benefits. In order to find a way to apply UAV to road crack detection, we developed a new technique for road crack detection based on UAV pictures, called DenxiDeepCrack, which is a trainable deep convolutional neural network for automatic crack detection which utilises learning high-level features for crack representation. In addition, we create a new dataset based on drone images called UCrack 11 to enrich the crack database of drone images for future crack detection research.
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Photovoltaic panels exposed to harsh environments such as mountains and deserts (e.g., the Gobi desert) for a long time are prone to hot-spot failures, which can affect power generation efficiency and even cause fires. The existing hot-spot fault detection methods of photovoltaic panels cannot adequately complete the real-time detection task; hence, a detection model considering both detection accuracy and speed is proposed. In this paper, the feature extraction part of YOLOv5 is replaced by the more lightweight Focus structure and the basic unit of ShuffleNetv2, and then the original feature fusion method is simplified. Considering that there is no publicly available infrared photovoltaic panel image dataset, this paper generates an infrared photovoltaic image dataset through frame extraction processing and manual annotation of a publicly available video. Consequently, the number of parameters of the model was 3.71 M, mAP was 98.1%, and detection speed was 49 f/s. A comprehensive comparison of the accuracy, detection speed, and model parameters of each model showed that the indicators of the new model are superior to other detection models; thus, the new model is more suitable to be deployed on the UAV platform for real-time photovoltaic panel hot-spot fault detection.
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BACKGROUND: This study aimed to describe the prevalence and lifetime criteria profiles of DSM-5 alcohol use disorder (AUD) and the transitions from alcohol use to disorder in Chifeng, China. METHODS: Face-to-face interviews were conducted using Composite International Diagnostic Interview-3.0 (CIDI-3.0) among 4528 respondents in Chifeng. RESULTS: The weighted lifetime and 12-month prevalence of DSM-5 AUD were 3.03 and 1.05%, respectively. Mild lifetime AUD was the most prevalent severity level (69.53%). The two most common criteria were "failure to quit/cutdown" and "drinking more or for longer than intended." Lifetime prevalence was 65.59% for alcohol use, and 22.97% for regular drinking. Male and domestic violence were risk factors for the transition from alcohol use to regular drinking or AUD and from regular drinking to AUD. Younger age was risk factor for the transition to AUD from alcohol use or regular drinking. Poverty (OR = 2.49) was risk factor for the transition from alcohol use to regular drinking. The earlier drinkers were more likely to develop to regular drinking (OR = 2.11). CONCLUSION: AUD prevalence in Chifeng was not as high as that in Western countries. The study revealed that multiple risk factors might contribute to the transition across different stages of alcohol use. Further research should explore the underlying mechanisms.
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Transtornos Relacionados ao Uso de Álcool , Alcoolismo , Consumo de Bebidas Alcoólicas/epidemiologia , Transtornos Relacionados ao Uso de Álcool/diagnóstico , Transtornos Relacionados ao Uso de Álcool/epidemiologia , Alcoolismo/diagnóstico , Alcoolismo/epidemiologia , China/epidemiologia , Manual Diagnóstico e Estatístico de Transtornos Mentais , Humanos , Masculino , Prevalência , Fatores de RiscoRESUMO
Self-sorting plays a crucial role in living systems such as the selective assembly of DNA and specific folding of proteins. However, the self-sorting of artificial helical polymers such as biomacromolecules has rarely been achieved. In this work, single-handed helical poly(phenyl isocyanide)s bearing pyrene (Py) and naphthalene (Np) probes were prepared, which exhibited interesting self-sorting properties driven by both helicity and molecular weight (Mn ) in solution, solid state, gel, and on the gel surface as well. The polymers with the same helix sense and similar Mn can self-sort and assemble into well-defined two-dimensional smectic architectures and form stable gels in organic solvents. In contrast, mixed polymers with opposite handedness or different Mn were repulsive to each other and did not aggregate. Moreover, the gels of helical polymers with the same handedness and similar Mn can recognize themselves and adhere together to form a gel.
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It is urgent to find a catalyst with high selectivity and efficiency for the reduction of CO2 by renewable electric energy, which is the important means to reduce the greenhouse effect. In this work, we report that the metal-organic framework (MOF) indium-based 1,4-benzenedicarboxylate (In-BDC) catalyzes CO2 to formate with a Faradaic efficiency (FEHCOO-) of more than 80% in a wide voltage range between -0.419 and -0.769 V (vs. reversible hydrogen electrode, RHE). In-BDC performs at a maximum FEHCOO- of 88% at -0.669 V (vs. RHE) and a turnover frequency of up to 4798 h-1 at -1.069 V (vs. RHE). The long-term durability of 21 h and reusability of the electrocatalyst are clearly demonstrated. It opens up a new opportunity to utilize MOF with novel metal motifs for the efficient electroreduction of CO2.
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A fiber-network chitosan film with three-dimensional interconnected structure was prepared in an alkali/urea solution and regenerated from an ethanol/water coagulation solution. The surface morphology and structure were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), N2 adsorption-desorption, attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR) and X-ray photoelectron spectroscopy (XPS). Batch adsorption for uranium U(VI) was conducted to investigate the effects of pH, contact time and initial uranium concentration on adsorption capacity. The adsorption of CS-80% was in good agreement with the pseudo-second-order kinetic model and Langmuir isotherm model. The three-dimensional interconnected structure provided more active sites and favored the diffusion of uranium solute, and therefore enhanced the adsorption capacity. The maximum adsorption capacity at pH 5 was 196.735 mg/g. The adsorption mechanism was attributed to chelation and coordination of uranium with -NH2 and -OH groups on chitosan molecules.
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Quitosana , Urânio , Poluentes Químicos da Água , Adsorção , Concentração de Íons de Hidrogênio , Cinética , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios XRESUMO
Controlling the self-assembly morphology of π-conjugated block copolymer is of great interesting. Herein, amphiphilic poly(3-hexylthiophene)-block-poly(phenyl isocyanide)s (P3HT-b-PPI) copolymers composed of π-conjugated P3HT and optically active helical PPI segments were readily prepared. Taking advantage of the crystallizable nature of P3HT and the chirality of the helical PPI segment, crystallization-driven asymmetric self-assembly (CDASA) of the block copolymers lead to the formation of single-handed helical nanofibers with controlled length, narrow dispersity, and well-defined helicity. During the self-assembly process, the chirality of helical PPI was transferred to the supramolecular assemblies, giving the helical assemblies large optical activity. The single-handed helical assemblies of the block copolymers exhibited interesting white-light emission and circularly polarized luminescence (CPL). The handedness and dissymmetric factor of the induced CPL can be finely tuned through the variation on the helicity and length of the helical nanofibers.
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Different polymorphic forms can affect the performance of the drug product. In addition, isomorphic crystals show different chemical and physical properties due to the changes in the crystal habit. However, it is unclear whether the crystal habit results in different pharmacological activity. The aim of this study was to investigate whether the pharmacological effect of ibuprofen could be affected due to the variety of the crystal habit. Solvent change technique and conventional fusion method were carried out to modify the characteristics of ibuprofen. The physicochemical properties of each were investigated using powder X-ray diffraction (PXRD), Fourier transform infrared (FT-IR) spectroscopy and differential scanning calorimetry (DSC) techniques. Results of scanning electron microscopy (SEM) analysis revealed differences in the surface characteristics of the crystals obtained. Further study revealed that the samples crystallized exhibited the remarkable variation on the dissolution profiles in different dissolution medium. Moreover, in vivo antinociceptive and anti-inflammatory findings demonstrated that the crystal habit modifications resulted in the different therapeutic efficacy. Taken together, these results indicate that the modification of the crystal habit had a great influence on the in vivo pharmacological activity of ibuprofen crystals.
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Ibuprofeno/química , Ibuprofeno/farmacologia , Analgésicos/química , Analgésicos/farmacologia , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Varredura Diferencial de Calorimetria/métodos , Química Farmacêutica/métodos , Cristalização/métodos , Camundongos , Camundongos Endogâmicos ICR , Microscopia Eletrônica de Varredura/métodos , Tamanho da Partícula , Pós/química , Pós/farmacologia , Ratos , Ratos Wistar , Solubilidade/efeitos dos fármacos , Solventes/química , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Difração de Raios X/métodosRESUMO
Four fluorocarbon polymers including polytetrafluoroethylene and polyvinylidene fluoride were coated on a stainless steel felt to separate emulsified water droplets from ultralow sulfur diesel (ULSD) fuels. The original fuel treated with clay to remove additives was additized again with four known surfactants including pentaerythrityoleate, (octadecadienoic acid) dipolymer, (octadecadienoic acid) tripolymer, and monoolein individually. The different surfactants adsorbed on the fuel-water interface reduce the interfacial intension with different intensities. The separation efficiency at various surfactant concentrations was used to evaluate the coalescence effect exerted by these coatings. It was found the separation was both surfactant- and coating-dependent. A fluoro-polyurethane coating (FC1) stood out to counteract the adverse effect of all the surfactants. Solid free energy was then measured using acid-base and Kaelble-Uy adhesion theories for all the coatings, but its correlation with coalescence was not found at all. Coating aging in surfactant-additized fuel on the coating's water wettability was also examined to better understand how historical wetting affects separation. A tumbled model for fluorocarbons was identified that well-explained the continuous decline of the water contact angle on the FC1 coating in fuel. Subject to the challenge of the foreign environment, the fluoroalkyl chains of the polymer tilt to expose the carbonyl groups underneath, resulting in favored coalescence separation in the presence of surfactants.
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SIRT6, with both deacetylase and ADP-ribosyltransferase activities, is predominantly expressed in the nucleus. It has been revealed that SIRT6 regulates various biological functions including metabolism, aging and stress resistance. This study aims to investigate the role of SIRT6 in vascular inflammation and it molecular mechanism. We found that tumor necrosis factor-α (TNF-α) did not alter the localization of SIRT6 in vascular adventitial fibroblasts (VAFs), vascular endothelial cells (VECs) and vascular smooth muscle cells (VSMCs). The expression of SIRT1, SIRT6 was decreased in TNF-α-treated VAFs. In contrast, TNF-α significantly increased the expression of monocyte chemotactic protein 1 (MCP-1) and interleukin (IL) -6. Knockdown of SIRT1 and SIRT6 by siRNA significantly enhanced TNF-α-induced expression of MCP-1 and IL-6, respectively. Overexpression of SIRT1 and SIRT6 inhibited TNF-α-induced expression of MCP-1 and IL-6 in VAFs. Moreover, we also found SIRT1 positively regulated the expression of SIRT6 in VAFs. In addition, knockdown of SIRT1 and SIRT6 respectively augmented TNF-α-induced generation of reactive oxygen species (ROS) and phosphorylation of protein kinase B (Akt). ROS scavenger N-acetyl-L-cysteine (NAC) and Akt inhibitor MK2206 reduced TNF-α-induced mRNA expression of MCP-1 and IL-6 in VAFs. In vivo studies indicated that the expression of SIRT1, SIRT6 was decreased and the expression of MCP-1, IL-6 and IL-1ß was increased in carotid collar-induced vascular inflammation. Taken together, these findings indicate that SIRT1 and SIRT6 inhibit TNF-α-induced inflammation in VAFs by ROS and Akt pathway.
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Fibroblastos/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos , Sirtuínas/metabolismo , Fator de Necrose Tumoral alfa/farmacologia , Animais , Células Endoteliais/metabolismo , Fibroblastos/metabolismo , Inflamação/induzido quimicamente , Inflamação/metabolismo , Interleucina-6/metabolismo , Ratos , Fator de Necrose Tumoral alfa/metabolismoRESUMO
The exploration of the relationship between zeolite composition and adsorption performance favored to facilitate its better application in removal of the hazardous substances from water. The adsorption capacity of rhodamine B (RB) onto Beta zeolite from aqueous solution was reported. The relationship between SiO2/Al2O3 ratio and adsorption capacity of Beta zeolite for RB was explored. The structure and physical properties of Beta zeolites with various SiO2/Al2O3 ratios were determined by XRD, FTIR, TEM, BET, UV-vis and so on characterizations. The adsorption behavior of rhodamine B onto Beta zeolite matched to Langmuir adsorption isotherm and more suitable description for the adsorption kinetics was a pseudo-second-order reaction model. The maximum adsorption capacity of the as-prepared Beta zeolite with SiO2/Al2O3 = 18.4 was up to 27.97mg/g.
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Rodaminas/análise , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Zeolitas/química , Adsorção , Óxido de Alumínio/química , Cinética , Modelos Teóricos , Dióxido de Silício/química , Soluções , Propriedades de SuperfícieRESUMO
In the present study, a novel and sensitive liquid spray dielectric barrier discharge induced plasma-chemical vapor generation technique (LSDBD-CVG) is developed for the determination of lead concentration by inductively coupled plasma mass spectrometry (ICPMS). The dissolved Pb2+ is readily converted to volatile species by LSDBD plasma induced chemical processes in the presence of 5% (v/v) formic acid in a supporting electrolyte (HCl, 0.01 mol L-1). In this LSDBD approach, the sample solution is converted to aerosol and simultaneously mixed with the DBD plasma generated at the nozzle of a pneumatic nebulizer, which greatly facilitates Pb vapor generation because of the enhanced interaction of sprayed analytes and the plasma. Optimal conditions for LSDBD-CVG were identified, and the interference effects from other metal ions were assessed. Under optimized conditions, the detection limit of Pb was found to be 0.003 µg L-1. The repeatability, expressed as the relative standard deviation (RSD) of the peak height, for the five replicate measurements of 0.03 and 1 µg L-1 lead standard, were 2.1% and 1.7%, respectively. Compared with other vapor generation methods, this new LSDBD-CVG offers several advantages including no requirement of unstable reagents, fast response, and easy coupling with flow injection, along with high tolerance for coexisting ions. The accuracy of the proposed method is demonstrated by successful analysis of Pb in reference material of stream sediment (GBW07311), soil (GBW07403), basalt (BCR-2), and simulated water sample (GBW08601). The proposed LSDBD-CVG extends the scope of elements accessible by plasma-CVG and provides an alternative efficient green approach for the vapor generation of Pb.
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BACKGROUND/AIMS: Autophagy is a lysosomal degradation pathway that is essential for cellular survival, differentiation, and homeostasis. Sirtuin 1 (SIRT1), a NAD+-dependent deacetylase, plays a pivotal role in modulation of autophagy. Recent studies found that autophagy was involved in the regulation of inflammatory response. In this study, we aimed to determine the effect of SIRT1 on autophagy and inflammation, and whether autophagy can regulate the inflammatory response in vascular adventitial fibroblasts (VAFs). METHODS: Cell autophagy was evaluated by fluorescence microscope and transmission electron microscopy. The expression of protein and mRNA were determined by Western blot analysis and real time-PCR. The production of cytokine was detected by ELISA. RESULTS: TNF-α induced autophagy and increased SIRT1 expression in VAFs. SIRT1 activator resveratrol enhanced TNF-α-induced VAF autophagy. In contrast, SIRT1 knockdown attenuated VAF autophagy. Both the Akt inhibitor MK2206 and mTOR inhibitor rapamycin further increased TNF-α-induced VAF autophagy. Furthermore, SIRT1 knockdown increased Akt phosphorylation and inhibited the autophagy in VAFs. However, MK2206 attenuated the effect of SIRT1 knockdown on VAF autophagy. In addition, ingenuity pathway analysis showed that there is a relationship between cell autophagy and inflammation. We found that SIRT1 knockdown increased the expression of NLRP3 and interleukin (IL)-6 and promoted the production of IL-1ß in VAFs. Further study showed that autophagy activation decreased the expression of NLRP3 and IL-6 and inhibited the production of IL-1ß, whereas autophagy inhibition increased the inflammatory response of VAFs. More importantly, our study showed that autophagy was involved in the degradation of NLRP3 through the autophagy-lysosome pathway. CONCLUSION: SIRT1 not only regulates VAF autophagy through the Akt/mTOR signaling pathway but also suppresses the inflammatory response of VAFs through autophagy.
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Autofagia , Transdução de Sinais , Sirtuína 1/metabolismo , Túnica Adventícia/citologia , Animais , Autofagia/efeitos dos fármacos , Benzamidas/farmacologia , Células Cultivadas , Fibroblastos/citologia , Fibroblastos/metabolismo , Compostos Heterocíclicos com 3 Anéis/farmacologia , Interleucina-1beta/análise , Interleucina-6/metabolismo , Masculino , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Naftóis/farmacologia , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-akt/metabolismo , RNA Interferente Pequeno/metabolismo , Ratos , Ratos Sprague-Dawley , Resveratrol , Transdução de Sinais/efeitos dos fármacos , Sirolimo/farmacologia , Sirtuína 1/antagonistas & inibidores , Sirtuína 1/genética , Estilbenos/farmacologia , Serina-Treonina Quinases TOR/antagonistas & inibidores , Serina-Treonina Quinases TOR/metabolismo , Fator de Necrose Tumoral alfa/farmacologiaRESUMO
Drug resistance is one of the major obstacles for improving the prognosis of breast cancer patients. Increasing evidence has linked the association of aberrantly expressed microRNAs (miRNAs) with tumour development and progression as well as chemoresistance. Despite recent advances, there is still little known about the potential role and mechanism of miRNAs in breast cancer chemoresistance. Here we describe that 16 miRNAs were found to be significantly down-regulated and 11 up-regulated in drug-resistant breast cancer tissues compared with drug-sensitive tissues, using a miRNA microarray. The results also showed miR-489 to be one of the most down-regulated miRNAs in drug-resistant tissues and cell lines, as confirmed by miRNA microarray screening and real-time quantitative PCR. A decrease in miR-489 expression was associated with chemoresistance as well as lymph node metastasis, increased tumour size, advanced pTNM stage and poor prognosis in breast cancer. Functional analysis revealed that miR-489 increased breast cancer chemosensitivity and inhibited cell proliferation, migration and invasion, both in vitro and in vivo. Furthermore, SPIN1, VAV3, BCL2 and AKT3 were found to be direct targets of miR-489. SPIN1 was significantly elevated in drug-resistant and metastatic breast cancer tissues and inversely correlated with miR-489 expression. High expression of SPIN1 was associated with higher histological grade, lymph node metastasis, advanced pTNM stage and positive progesterone receptor (PR) status. Increased SPIN1 expression enhanced cell migration and invasion, inhibited apoptosis and partially antagonized the effects of miR-489 in breast cancer. PIK3CA, AKT, CREB1 and BCL2 in the PI3K-Akt signalling pathway, demonstrated to be elevated in drug-resistant breast cancer tissues, were identified as downstream effectors of SPIN1. It was further found that either inhibition of SPIN1 or overexpression of miR-489 suppressed the PI3K-Akt signalling pathway. These data indicate that miR-489 could reverse the chemoresistance of breast cancer via the PI3K-Akt pathway by targeting SPIN1. Copyright © 2016 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
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Neoplasias da Mama/metabolismo , Proteínas de Ciclo Celular/metabolismo , Resistencia a Medicamentos Antineoplásicos/genética , MicroRNAs/metabolismo , Proteínas Associadas aos Microtúbulos/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Fosfoproteínas/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/fisiologia , Apoptose/efeitos dos fármacos , Mama/metabolismo , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Proteínas de Ciclo Celular/genética , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , MicroRNAs/genética , Proteínas Associadas aos Microtúbulos/genética , Pessoa de Meia-Idade , Fosfoproteínas/genéticaRESUMO
Recent studies demonstrated that the ligand-activated transcription factor peroxisome proliferator-activated receptorα (PPARα) acts in association with histone deacetylase sirtuin 1 (SIRT1) in the regulation of metabolism and inflammation involved in cardiovascular diseases. PPARα activation also participates in the modulation of cell apoptosis. Our previous study found that SIRT1 inhibits the apoptosis of vascular adventitial fibroblasts (VAFs). However, whether the role of PPARα in apoptosis of VAFs is mediated by SIRT1 remains unknown. In this study, we aimed to determine the effect of PPARα agonist fenofibrate on cell apoptosis and SIRT1 expression and related mechanisms in ApoE(-/-) mice and VAFs in vitro. We found that fenofibrate inhibited cell apoptosis in vascular adventitia and up-regulated SIRT1 expression in aorta of ApoE(-/-) mice. Moreover, SIRT1 activator resveratrol (RSV) further enhanced these effects of fenofibrate. In vitro study showed that activation of PPARα by fenofibrate inhibited TNF-α-induced cell apoptosis and cell cycle arrest in VAFs. Meanwhile, fenofibrate up-regulated SIRT1 expression and inhibited SIRT1 translocation from nucleus to cytoplasm in VAFs stimulated with TNF-α. Moreover, the effects of fenofibrate on cell apoptosis and SIRT1 expression in VAFs were reversed by PPARα antagonist GW6471. Importantly, treatment of VAFs with SIRT1 siRNA or pcDNA3.1(+)-SIRT1 showed that the inhibitory effect of fenofibrate on cell apoptosis in VAFs through SIRT1. On the other hand, knockdown of FoxO1 decreased cell apoptosis of VAFs compared with fenofibrate group. Overexpression of FoxO1 increased cell apoptosis of VAFs compared with fenofibrate group. Further study found that fenofibrate decreased the expression of acetylated-FoxO1 in TNF-α-stimulated VAFs, which was abolished by SIRT1 knockdown. Taken together, these findings indicate that activation of PPARα by fenofibrate inhibits cell apoptosis in VAFs partly through the SIRT1-mediated deacetylation of FoxO1.
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Apoptose/efeitos dos fármacos , Fenofibrato/farmacologia , Fibroblastos/metabolismo , Fatores de Transcrição Forkhead/metabolismo , Hipolipemiantes/farmacologia , PPAR alfa/metabolismo , Sirtuína 1/metabolismo , Acetilação , Túnica Adventícia/citologia , Animais , Vasos Sanguíneos/citologia , Pontos de Checagem do Ciclo Celular , Células Cultivadas , Proteína Forkhead Box O1 , Masculino , Camundongos Knockout , Processamento de Proteína Pós-Traducional , Ratos Sprague-Dawley , Fator de Necrose Tumoral alfa/fisiologiaRESUMO
Currently, the technological development of non-destructive analysis and micro-damage analysis of turquoise is fast. LA-ICP-AES, an almost non-destructive analysis, has multiple advantages. This paper attempts to use this analysis method to examine sample turquoise from five places of origin on Mount East Qinling, including ancient turquoise ore in Laziya, in order to attain its major element and microelement data. Then the paper uses PCA to analyze and study its chemical elements in a comparative way. Three main elements are gained through analysis, and their cumulative variance contribution rate has reached 84.96%. The former two main elements' variance contribution rate is 72.289%. Therefore, the corresponding elements, including V2O5, NiO, B2O3, SrO, BaO, CaO, ZrO, MnO2, are the featured chemical elements of turquoise from different places of origin. Through comparative analysis and research on corresponding chemical elements, turquoise samples produced by different ores vary in terms of the content of some chemical element and chemical components. Two analysis methods combined together will basically realize the appreciation of turquoise in various places of origin. In addition, the research indicates that some chemical contents have positive or negative correlations. Such correlations can be regarded as features of producing area, and can also provide clues as to the cause of formation of turquoise ore. This study preliminarily indicates that LA-ICP-AES combined with PCA and comparative analysis of chemical composition and content has the function of distinguishing turquoise produced in different places of origin to a certain extent.