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Statistics provided by GLOBOCAN list gastric cancer as the sixth most common, with a mortality ranking of third highest for the year 2020. In China, a herb called Rabdosia rubescens (Hemsl.) H.Hara, has been used by local residents for the treatment of digestive tract cancer for hundreds of years. Oridonin, the main ingredient of the herb, has a curative effect for gastric cancer, but the mechanism has not been previously clarified. This study mainly aimed to investigate the role of TNF-alpha/Androgen receptor/TGF-beta signalling pathway axis in mediating the proliferation inhibition of oridonin on gastric cancer SGC-7901 cells. MTT assay, cell morphology observation assay and fluorescence assay were adopted to study the efficacy of oridonin on cell proliferation. The network pharmacology was used to predict the pathway axis regulated by oridonin. Western blot assay was adopted to verify the TNF-α/Androgen receptor/TGF-ß signalling pathway axis regulation on gastric cancer by oridonin. The results showed Oridonin could inhibit the proliferation of gastric cancer cells, change cell morphology and cause cell nuclear fragmentation. A total of 11signaling pathways were annotated by the network pharmacology, among them, Tumour necrosis factor alpha (TNF-α) signalling pathway, androgen receptor (AR) signalling pathway and transforming growth factor (TGF-ß) signalling pathway account for the largest proportion. Oridonin can regulate the protein expression of the three signalling pathways, which is consistent with the results predicted by network pharmacology. These findings indicated that oridonin can inhibit the proliferation of gastric cancer SGC-7901 cells by regulating the TNF-α /AR /TGF-ß signalling pathway axis.
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Diterpenos do Tipo Caurano , Neoplasias Gástricas , Humanos , Neoplasias Gástricas/patologia , Receptores Androgênicos , Fator de Crescimento Transformador beta/farmacologia , Fator de Necrose Tumoral alfa/metabolismo , Linhagem Celular Tumoral , Diterpenos do Tipo Caurano/farmacologia , Diterpenos do Tipo Caurano/uso terapêutico , Proliferação de Células , ApoptoseRESUMO
A novel CaIn2S4with three-dimensional octahedral nano-blocks (ONBs) are successfully synthesized on fluorine-doped tin oxide (FTO) substrate by a simple hydrothermal method. The CaIn2S4ONBs are uniform grown and scattered on the whole FTO substrate with high regular and symmetric morphology as well as average diagonal length of about 600 nm. Based on the as-synthesized CaIn2S4ONBs, a photodetector (PD) is fabricated. Satisfyingly, it is found that the CaIn2S4ONBs PD achieves a broad-band response ranging from ultraviolet (UV) to visible ( vis) light at zero bias voltage. It is also significant that the CaIn2S4ONBs PD enables a fast response, in which the rise time and decay time are less than 0.15 and 0.2 s, respectively. Furthermore, the morphological evolution of the CaIn2S4ONBs and plausible UV/vis detection mechanism of the CaIn2S4ONBs PD are discussed.
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BACKGROUND: Liver cancer is the sixth most commonly diagnosed cancer and the fourth most common cause of cancer death. The purpose of this work is to find new diagnostic biomarkers or prognostic biomarkers and explore the biological functions related to the prognosis of liver cancer. METHODS: GSE25097 datasets were firstly obtained and compared with TCGA LICA datasets and an analysis of the overlapping differentially expressed genes (DEGs) was conducted. Cytoscape was used to screen out the Hub Genes among the DEGs. ROC curve analysis was used to screen the Hub Genes to determine the genes that could be used as diagnostic biomarkers. Kaplan-Meier analysis and Cox proportional hazards model screened genes associated with prognosis biomarkers, and further Gene Set Enrichment Analysis was performed on the prognosis genes to explore the mechanism affecting the survival and prognosis of liver cancer patients. RESULTS: 790 DEGs and 2162 DEGs were obtained respectively from the GSE25097 and TCGA LIHC data sets, and 102 Common DEGs were identified by overlapping the two DEGs. Further screening identified 22 Hub Genes from 102 Common DEGs. ROC and survival curves were used to analyze these 22 Hub Genes and it was found that there were 16 genes with a value of AUC > 90%. Among these, the expression levels of ESR1,SPP1 and FOSB genes were closely related to the survival time of liver cancer patients. Three common pathways of ESR1, FOBS and SPP1 genes were identified along with seven common pathways of ESR1 and SPP1 genes and four common pathways of ESR1 and FOSB genes. CONCLUSIONS: SPP1, AURKA, NUSAP1, TOP2A, UBE2C, AFP, GMNN, PTTG1, RRM2, SPARCL1, CXCL12, FOS, DCN, SOCS3, FOSB and PCK1 can be used as diagnostic biomarkers for liver cancer, among which FOBS and SPP1 genes can also be used as prognostic biomarkers. Activation of the cell cycle-related pathway, pancreas beta cells pathway, and the estrogen signaling pathway, while on the other hand inhibition of the hallmark heme metabolism pathway, hallmark coagulation pathway, and the fat metabolism pathway may promote prognosis in liver cancer patients.
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Biomarcadores Tumorais/metabolismo , Neoplasias Hepáticas/genética , Humanos , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/patologia , Prognóstico , Análise de SobrevidaRESUMO
Bismuth telluride (Bi2Te3), as an emerging two-dimensional (2D) material, has attracted extensive attention from scientific researchers due to its excellent optoelectronic, thermoelectric properties and topological structure. However, the application research of Bi2Te3mainly focuses on thermoelectric devices, while the research on optoelectronic devices is scarce. In this work, the morphology evolution and growth mechanism of 2D Bi2Te3nanosheets with a thickness of 12 ± 3 nm were systematically studied by solvothermal method. Then, the Bi2Te3nanosheets were annealed at 350 °C for 1 h and applied to self-powered photoelectrochemical-type broadband photodetectors. Compared with the as-synthesized Bi2Te3photodetector, the photocurrent of the photodetector based on the annealed Bi2Te3is significantly enhanced, especially enhanced by 18.3 times under near-infrared light illumination. Furthermore, the performance of annealed Bi2Te3photodetector was systematically studied. The research results show that the photodetector not only has a broadband response from ultraviolet to near-infrared (365-850 nm) under zero bias voltage, but also obtains the highest responsivity of 6.6 mA W-1under green light with an incident power of 10 mW cm-2. The corresponding rise time and decay time are 17 ms and 20 ms, respectively. These findings indicate that annealed Bi2Te3nanosheets have great potential to be used as self-powered high-speed broadband photodetectors with high responsivity.
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Two novel benzo[1,2-b:4,5-b' ]difuran (BDF)-based wide-bandgap polymers, PBDFT-FBz and PBDFF-FBz, featuring a difluorobenzotriazole (FBz) acceptor unit, are designed and synthesized. The first attempt through main-chain engineering to alter thiophene units to furan units in the main chain of PBDFT-FBz, and further side-chain engineering eliminate the 2-ethylthiophenyl side chains of PBDFT-FBz by 2-ethylfuryl side chains to generate the "all-furan" polymer PBDFF-FBz. By taking the benefit of the oxygen atom in furan, both PBDFT-FBz and PBDFF-FBz exhibit lower HOMO energy levels and enhanced polymer chain interactions compared to their benzo[1,2-b:4,5-b' ]dithiophene (BDT)-based counterparts. As a result, while applying both polymers in non-fullerene polymer solar cells with non-fullerene acceptor m-ITIC, both devices exhibit highly promising photovoltaic performance. The power conversion efficiency (PCE) in the PBDFT-FBz device reaches 7.57% with increased open circuit voltage (Voc ) and fill factor (FF) compared to the PCE of 5.98% in its BDT counterpart (J52). A further increased PCE is obtained (8.79%) in the PBDFF-FBz:m-ITIC device, which shows ≈47% enhancement in device performance compared to that of J52. The large increase in photovoltaic performance is attributed to the lower-lying HOMO energy levels and better chain interactions in these BDF-based polymers.
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Benzofuranos/química , Polímeros/química , Energia Solar , Fontes de Energia Elétrica , Estrutura Molecular , Polímeros/síntese químicaRESUMO
A room temperature successive ionic layer adsorption and reaction (SILAR) method is introduced for fabricating quantum dots-on-wide bandgap semiconductors. Detailed exploration of how SILAR begins and proceeds is performed by analyzing changes in the electronic structure of related elements at interfaces by X-ray photoelectric spectroscopy, together with characterization of optical properties and X-ray diffraction. The distribution of PbS QDs on ZnO, which is critical for optoelectrical applications of PbS with a large dielectric constant, shows a close relationship with the dipping order. A successively deposited PbS QDs layer is obtained when the sample is first immersed in Na2S solution. This is reasonable because the initial formation of different chemical bonds on ZnO nanorods is closely related to dangling bonds and defect states on surfaces. Most importantly, dipping order also affects their optoelectrical characteristics greatly, which can be explained by the heterojunction energy band structure related to the interface. The formation mechanism for PbS QDs on ZnO is confirmed by the fact that the photovoltaic diode device performance is closely related to the dipping order. Our atomic-scale understanding emphasises the fundamental role of surface chemistry in the structure and tuning of optoelectrical properties, and consequently in devices.
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R-Phycoerythrin (R-PE), one of the chemical constituents of red algae, could produce singlet oxygen upon excitation with the appropriate radiation and possibly be used in photodynamic therapy (PDT) for cancer. Documents reported that R-PE could inhibit cell proliferation in HepG2 and A549 cells, which was significative for cancer therapy. This is due to the fact that R-PE could kill cancer cells directly as well as by PDT. However, little is known about the cytotoxicity of R-PE to the SGC-7901 cell. In this study, it has been found that R-PE could inhibit SGC-7901 proliferation and induce cell apoptosis, which was achieved by arresting the SGC-7901 cell at S phase. CyclinA, CDK2 and CDC25A are proteins associated with the S phase, and it was found that R-PE could increase the expression of cyclin A protein and decrease the expression of CDK2 and CDC25A proteins. Thus, it was concluded that R-PE reduced the CDK2 protein activated through decreasing the CDC25A factor, which reduced the formation of Cyclin-CDK complex. The reduction of Cyclin-CDK complex made the SGC-7901 cells arrest at the S phase. Therefore, R-PE induced apoptosis by arresting the SGC-7901 cell at S phase was successful, which was achieved by the expression of the CDC25A protein, which reduced the CDK2 protein actived and the formation of Cyclin-CDK complex.
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Apoptose/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Ficoeritrina/farmacologia , Fase S/efeitos dos fármacos , Proteínas de Ciclo Celular/antagonistas & inibidores , Proteínas de Ciclo Celular/biossíntese , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Ciclina A/biossíntese , Ciclina A/genética , Quinase 2 Dependente de Ciclina/biossíntese , Quinase 2 Dependente de Ciclina/genética , Humanos , Fosfatases cdc25/biossíntese , Fosfatases cdc25/genéticaRESUMO
Sauromatum giganteum (Engl.) Cusimano & Hett Tuber are used in Chinese folklore medicine for treatment of neoplasms. However, the claim has not been scientifically validated. The aim of the study is to screen the antitumor bioactive fraction of Sauromatum giganteum (Engl.) Cusimano & Hett Tuber and sensitive tumor cell lines using a cytotoxicity assay in vitro and tumor transplantation method in vivo, to support its use in folk medicine. The petroleum ether fraction, chloroform fraction, ethyl acetate fraction, n-butanol fraction and water fraction were successively extracted by turn by the maceration under reflux assay. Screening of antitumor bioactive fraction and sensitive cell lines were measured by MTT assay and the serum pharmacology method, and in vivo the antitumor activities of the active fraction was evaluated by using S180 or H22 tumor-bearing mice model and Kunming mice. The active constituents of ethyl acetate fraction of Sauromatum giganteum (Engl.) Cusimano & Hett were characterized by UPLC-TOF-MS. Compared with control groups, mice serum containing ethyl acetate fraction had a inhibition effect on SMMC-7721 cell, SGC-7901 cell, MCF-7 cell, HeLa cell, A549 cell, HT-29, and MDA-MB-231, respectively, but mice serum containing other four fractions had no different with that of control group. The inhibition capabilities of mice serum containing ethyl acetate fraction on the seven cell lines in descending order is SGC-7901 > SMMC-7721 > MCF-7 > HT-29 > A549 > HeLa > MDA-MB-231. In vivo the inhibition rate of 106, 318, 954 mg/kg·d ethyl acetate fraction dry extract to sarcoma S180 is 15.22%, 26.15% and 40.24%, respectively, and life prolonging rate to hepatoma H22 is 33.61%, 40.16% and 55.74%. A total of 14 compounds were identified in the ethyl acetate fraction of Sauromatum giganteum (Engl.) Cusimano & Hett. The results of the experimental studies proved the antitumor activity of Sauromatum giganteum (Engl.) Cusimano & Hett and supported the traditional use of this plant. These data indicate the potential for the use of ethyl acetate fraction of Sauromatum giganteum (Engl.) Cusimano & Hett Tuber in tumor therapy, anti-tumor activity on cancer cell line in descending order is SGC-7901 > SMMC-7721 > MCF-7 > HT-29 > A549 > HeLa > MDA-MB-231.
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Antineoplásicos Fitogênicos/farmacologia , Araceae/química , Proliferação de Células/efeitos dos fármacos , Neoplasias/tratamento farmacológico , Extratos Vegetais/farmacologia , Tubérculos/química , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Animais , Cromatografia Líquida , Feminino , Humanos , Masculino , Camundongos , Neoplasias/metabolismo , Neoplasias/patologia , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
ETHNOPHARMACOLOGICAL RELEVANCE: In 2020, liver cancer contributed to approximately 0.9 million new cases and 0.83 million deaths, making it the third leading cause of mortality worldwide. Andrographis paniculata (Burm.f.) Nees(APN), a traditional Chinese or ethnic medicine extensively utilized in Asia, has been historically employed for treating hepatitis and liver cancer. However, the precise molecular mechanism responsible for its therapeutic efficacy remains unclear. AIM OF THE STUDY: To identify and replace the active components of APN on liver cancer, which is investigate the potential of a Multi-Component Chinese Medicine derived from Andrographis paniculata (Burm.f.) Nees(APN-MCCN) for the treatment of liver cancer. MATERIALS AND METHODS: Firstly, the TCMSP database and two liver cancer disease databases were utilized to optimize the chemical constituents of APN and the disease-related targets of liver cancer. The network was constructed using Cytoscape to visualize the relationships between them. Subsequently, the optimal combination of components in APN-MCCN for the treatment of liver cancer was determined using the contribution index method. HPLC analysis was performed to measure the content of each component. Pathway enrichment and gene annotation were conducted using the ClueGo plugin. In vivo efficacy was evaluated by transplanting S180 and H22 tumor-bearing mouse models. In vitro efficacy was determined through MTT assay, morphological observations, flow cytometry analysis, and scratch tests. Western blotting was used to validate the protein expression. The transfection techniques were employed to knockdown the expressions of key protein in different pathway. RESULTS: We obtained 24 effective compounds, with andrographolide contributing 20.78%, wogonin contributing 41.85%, and oroxylin A contributing 30.26% to the overall composition. Based on the predicted enrichment degree and correlation with liver cancer, we identified a total of 27 pathways, among which the Leptin signaling pathway, AGE-RAGE signaling pathway, and Cell Cycle signaling pathway were selected for further investigation. The content of andrographolide, oroxylin A, and wogonin in APN was found to be 0.104%, 0.0024%, and 0.0052%, respectively. In vivo experiments demonstrated that APN-MCCM significantly reduced tumor weight in S180 tumor-bearing mice and prolonged the survival time of H22 liver cancer-bearing mice. APN-MCCM exhibited inhibitory effects on the proliferation, apoptosis, and migration of liver cancer cells while arresting them in the G2/M phase. Furthermore, APN-MCCM down-regulated the protein expression of NCOA1, PTPN1, and GSK3B in the Leptin signaling pathway, NOS2 and NOS3 in the AGE-RAGE signaling pathway, CCNA2, CDK1, CDK2, and CDK7 in the Cell Cycle signaling pathway. Additionally, it upregulated the protein phosphorylation of p-P38 and p-JUN in the AGE-RAGE signaling pathway. Knockout experiments revealed that the inhibitory effect of APN-MCCM on liver cancer cell migration was prevented when the MAPK or NCOA1 genes were knocked out. Similarly, knocking out the CDK7 gene blocked the G2/M phase arrest induced by APN-MCCM in liver cancer cells. CONCLUSIONS: APN-MCCM, consisting of andrographolide, wogonin, and oroxylin A, exhibits inhibitory effects on the cell proliferation of liver cancer cells by targeting the cell cycle pathway. Additionally, it suppresses the migration of liver cancer cells through the AGE-RAGE and Leptin signaling pathways.
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Andrographis , Carcinoma Hepatocelular , Ciclo Celular , Proliferação de Células , Diterpenos , Flavonoides , Leptina , Neoplasias Hepáticas , Transdução de Sinais , Animais , Proliferação de Células/efeitos dos fármacos , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/patologia , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/metabolismo , Diterpenos/farmacologia , Diterpenos/isolamento & purificação , Humanos , Transdução de Sinais/efeitos dos fármacos , Andrographis/química , Camundongos , Ciclo Celular/efeitos dos fármacos , Flavonoides/farmacologia , Flavonoides/isolamento & purificação , Leptina/metabolismo , Antineoplásicos Fitogênicos/farmacologia , Antineoplásicos Fitogênicos/uso terapêutico , Antineoplásicos Fitogênicos/isolamento & purificação , Masculino , Linhagem Celular Tumoral , Células Hep G2 , Camundongos Nus , Ensaios Antitumorais Modelo de Xenoenxerto , Camundongos Endogâmicos BALB C , FlavanonasRESUMO
Among the two-dimensional (2D) Bi2O2X (X = S, Se, and Te) series, Bi2O2Te has the smallest effective mass and the highest carrier mobility. However, Bi2O2Te has rarely been investigated, most likely due to the lack of feasible methods to synthesize 2D Bi2O2Te. Herein, 2D Bi2O2Te nanosheets are successfully synthesized by low-temperature oxidation of Bi2Te3 nanosheets synthesized using a solvothermal method. The performance of a quasi-solid-state photoelectrochemical-type (PEC-type) photodetector based on 2D Bi2O2Te nanosheets is systematically investigated. Remarkably, the device has a high responsivity of 20.5 mA W-1 (zero bias) and fast rise/fall times of 6/90 ms under 365 nm illumination, which is superior to the majority of PEC-type photodetectors based on bismuth-based compounds. More importantly, due to the strong anisotropy of 2D Bi2O2Te nanosheets, the device achieves a dichroic ratio as high as 52, which belongs to the state-of-the-art polarized photodetectors. Besides, the capacity of 2D Bi2O2Te for high-resolution polarization imaging is demonstrated. This work provides a promising strategy for the synthesis of 2D Bi2O2Te nanosheets to fabricate a high-performance and polarization-sensitive photodetector.
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Recently, different kinds of energy band structures have been utilized to improve the photoelectric properties of zinc oxide (ZnO). In this work, ZnO nanorods were prepared by the hydrothermal method and then decorated with silver sulfide (Ag2S)/zinc sulfide (ZnS) via two-step successive ionic layer adsorption and reaction method. The photoelectric properties of nanocomposites are investigated. The results show that ZnO decorated with Ag2S/ZnS can improve the photocurrent of photodetectors from 0.34 to 0.56 A at bias of 9 V. With the immersion time increasing from 15 to 60 minutes, the photocurrent of photodetectors increases by 0.22 A. The holes in the valence band of ZnO can be transferred to the valence band of ZnS and Ag2S, which promotes the separation and suppresses the recombination of hole-electron pairs generated in ZnO. Moreover, electrons excited by ultraviolet (UV) light in Ag2S can also be injected into the conduction band of ZnO, which causes the photocurrent to increase more than the ZnO photodetector.
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BACKGROUND: Recent scientific research has enabled the identification of macrophages related-genes (MaRG), which play a key role in the control of the immune microenvironment in many human cancers. However, the functional role of MaRGs in human tumors is ill-defined. Herein, we aimed at bioinformatically exploring the molecular signatures of MaRGs in colorectal cancer. METHODS: A list of MaRGs was generated and their differential expression was analyzed across multiple datasets downloaded from the publicly available functional genomics database Gene Expression Omnibus. The weighted gene co-expression network analysis (WGCNA) was also applied to identify the partner genes of these MaRGs in colorectal cancer. RESULTS: After integration of the results from analyses of different datasets, we found that 29 differentially expressed MaRGs (DE-MaRGs) could be considered as CRC-related genes as obtained from the WGCNA analysis. These genes were functionally involved in positive regulation of DNA biosynthetic process and glutathione metabolism. Protein-protein interaction network analysis indicated that PDIA6, PSMA1, PRC1, RRM2, HSP90AB1, CDK4, MCM7, RFC4, and CCT5 were the hub MaRGs. The LASSO approach was used for validating the 29 MaRGs in TCGA-COAD and TCGA-READ data and the results showed that ten among the 29 genes could be considered as MaRGs significantly involved in CRC. The maftools analysis showed that MaRGs were mutated at varying degrees. The nomogram analysis indicated the correlation of these MaRGs with diverse clinical features of CRC patients. CONCLUSIONS: Conclusively, the present disclosed a signature of MaRGs as potential key regulators involved in CRC pathogenesis and progression. These findings contribute not only to the understanding of the molecular mechanism of CRC pathogenesis but also to the development of adequate immunotherapies for CRC patients.
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Mapas de Interação de ProteínasRESUMO
The ambient stability and processability of organic solar cells (OSCs) are important factors for their commercialization. Herein, we selected four benzo[1,2-b:4,5-b']difuran (BDF) polymers and two electron acceptors to examine the role of photovoltaic materials in the ambient stability. The investigations revealed that the MoOx layer is the detrimental factor for the ambient stabilities. The penetration of MoOx into the active layer and their interactions will strengthen the interface and form a favorable contact, hence leading to the increased photovoltaic performance, in which the efficiency loss induced by air was balanced out. As such, these BDF polymer-based non-fullerene (NF) OSCs possessed very promising ambient stabilities even after â¼1000 h with the almost maintained power conversion efficiencies (PCEs). These results drive us to further investigate the ambient processability of these NF-OSCs. The PCEs from the devices processed under ambient condition only possessed 0.3-2% loss compared to those devices under inert conditions, which suggest the significant potentials of BDF polymers to develop highly efficient and stable NF-OSCs for the practical applications.
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Single pure organic molecular white light emitters (SPOMWLEs) are of significance as a new class of material for white lighting applications; however, few of them are able to emit white electroluminescence from organic light-emitting diodes. Herein, donor-π-acceptor conjugated emitters, 2PQ-PTZ and 4PQ-PTZ, were designed and synthesized as SPOMWLEs for white light emission considering the distinct advantages of their conformation isomers. The coexistence of conformational isomers in 2PQ-PTZ, which is the first experimental evidence of the coexisting quasi-axial and quasi-equatorial conformers, provides ideal flexibility to obtain white light emission from their simultaneous and well-separated fluorescence and thermally activated delayed fluorescence. With these remarkable properties, a 2PQ-PTZ-based white light-emitting diode (LED) with a CIE of (0.32, 0.34) and color rendering index (CRI) of 89 is demonstrated. Further, the white organic light-emitting diode (OLED) of 2PQ-PTZ exhibits a high external quantum efficiency (EQE) of 10.1%, which is the reported highest performance among SPOMWLE-based OLEDs.
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Photocatalytic water splitting into hydrogen is regarded as one of the key solutions to the deterioration of the global environment and energy. Due to the significantly reduced grain boundaries, ZnO nanorods facilitate a fast electron transfer through their smooth tunnels and are well suited as a photocatalyst. However, the photocatalytic hydrogen evolution performance of pristine ZnO nanorods is still low due to the high recombination rate of photogenerated electron-hole pairs and the less light absorption. Here, a novel structure about black ZnO nanorods (NRs)/TiO2-X mesoporous spheres (MSs) heterojunction has been prepared and the photocatalytic hydrogen evolution performance has been explored. The photocatalytic activity test results showed that ZnO NRs/TiO2-X MSs exhibited higher catalytic activity than ZnO NRs for hydrogen production. Compared to the pure ZnO NRs photoanode, the photocurrent of ZnO NRs/TiO2-X MSs heterojunction photoanode could reach 0.41 mA/cm2 in view of the expanding spectral response region and effective inhibition of e-/h+ recombination at the same condition. Using a relatively integrated experimental investigation and mechanism analysis, we scrutinized that after being treated with NaBH4, TiO2 MSs introduce oxygen vacancies expanding the photocatalytic activity of pure TiO2, and improving conductivity and charge transport capabilities through coating on ZnO NRs. More importantly, the results provide a promising approach in the NRs/MSs composite structure serving as photoanodes for photocatalytic hydrogen production.
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In this work, MoS2 microspheres/PtCo-alloy nanoparticles (MoS2/PtCo-alloy NPs) were composited via a novel and facile process which MoS2 is functionalized by poly (N-vinyl-2-pyrrolidone) (PVP) and self-assembled with PtCo-alloy NPs. This new composite shows excellent electrocatalytic activity and great potential for dye-sensitized solar cells (DSSCs) as a counter electrode (CE) material. Benefiting from heterostructure and synergistic effects, the MoS2/PtCo-alloy NPs exhibit high electrocatalytic activity, low charge-transfer resistance and stability in the cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) test. Meanwhile, a high power-conversion efficiency (PCE) of 8.46% is achieved in DSSCs with MoS2/PtCo-alloy NP CEs, which are comparable to traditional Pt CEs (8.45%). This novel composite provides a new high-performance, stable and cheap choice for CEs in DSSCs.
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OBJECTIVE: To study how the way in which betaine promotes the proliferation of mouse spleen lymphocytes is related to calcium channels. METHOD: BALB/c mice were used for this experiment. Mouse spleen lymphocytes were obtained through in vitro cultivation after they had been separated, and were divided into a negative control group, a Con A group, and 0.04, 0.4, 4, and 20 mmol x L(-1) betaine groups. MTT was used to observe the effect of betaine on the proliferation of mouse spleen lymphocytes; flow cytometry was used to measure the changes in the cell cycle of mouse spleen lymphocytes; and laser confocal scanning microscopy was used to observe the changes in the intracellular [Ca2+]i of mouse spleen lymphocytes after betaine or different calcium channel blockers were applied. RESULT: Betaine was found to promote the proliferation of mouse spleen lymphocytes 12 h after it had been applied in vitro in concentrations of 4 and 20 mmol x L(-1). It was also found to promote the proliferation of mouse spleen lymphocytes 24 h and 48 h after it had been applied in vitro in concentrations of 0.04, 0.4, 4, and 20 mmol x L(-1), with the effect being most marked for the 4 mmol x L(-1) group 24 h after its application. It was found to facilitate the entry of mouse spleen lymphocytes from the G0/G1 to the S phase 4, 6, 18, and 24 h after it had been applied to mouse spleen lymphocytes in a concentration of 4 mmol x L(-1), with the effect being most marked at 18 h after its application. Intracellular [Ca2+]i in mouse spleen lymphocytes increased significantly (P < 0.01) 6, 12, 18 h after 4 mmol x L(-1) betaine had acted on the lymphocytes, with the effect being most marked at 6 h. The calcium channel blockers nifidipine, diltiazem, mibefradil, and genistein had no effect on the increase of the intracellular [Ca2+]i in mouse spleen lymphocytes due to the application of betaine, while verapamil, mycifradin, heparin, and procaine could block such increase. CONCLUSION: Betaine facilitates the entry of mouse spleen lymphocytes from the G0/G1 into the S phase by raising the intracellular [Ca2+]i in these cells, thus promoting their proliferation. Intracellular [Ca2+]i increases mainly in two ways: (1) By affecting the alpha1 subunit of the L-type voltage-gated calcium channel with mediation by G proteins and thus leading to an efflux of intracellular calcium: (2) By affecting the IP3R and RyR calcium channels of the intracellular calcium stores and thus leading to the release of intracellular calcium.
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Betaína/farmacologia , Canais de Cálcio/metabolismo , Proliferação de Células/efeitos dos fármacos , Linfócitos/metabolismo , Animais , Cálcio/metabolismo , Ciclo Celular/efeitos dos fármacos , Feminino , Linfócitos/citologia , Linfócitos/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos BALB CRESUMO
A novel fused perylene diimide (PDI)-based polymer electron acceptor (PFPDI-BDF) with a built-in twisting configuration was constructed for application in all-polymer solar cells (all-PSCs). To shed light on the compatibility of the FPDI polymer acceptor and to identify a suitable polymer donor for device applications, we considered herein to investigate three polymer donors (PBDB-T, PTB7-Th, and PCPDTFBT) with different optical and electronic properties as well as polymer chain packing behavior for comparing the device performance. After being fabricated with PFPDI-BDF, polymer donor PBDB-T with a wide band gap showed a decent power conversion efficiency (PCE) of 4.86% with an open-circuit voltage (Voc) of 0.82 V, a short-circuit current density (Jsc) of 8.94 mA cm-2, and a recorded fill factor (FF) of 66.3%, which is one of the best FF reported for PDI-based all-polymer solar cells (all-PSCs). The enhanced efficiency of 6.05% was found in the medium band gap polymer PTB7-Th devices due to the more complementary absorption region that makes the photoactive blends absorb more photons, giving rise to an increased Jsc of 12.97 mA cm-2. On the other hand, due to the inferior exciton dissociation/extraction efficiency and unfavorable morphology compatibility, the narrow band gap polymer donor PCPDTFBT/PFPDI-BDF devices exhibited the worst PCE of only 0.71% with a low Jsc of 2.2 mA cm-2 and a FF of 42.4%.
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OBJECTIVE: To explore how arylamine N-acetyltransferases (NATs) is related to cell apoptosis. METHODS: NAT activity in apoptotic HepG2 cells was measured using high performance liquid chromatography (HPLC); the apoptosis rate of HepG2 cells acted upon by an NAT inhibitor was measured using flow cytometry. RESULTS: NAT activity was lowered in apoptotic HepG2 cells; apoptosis rate induced by camptothecin (CAM) increased after inhibition of NAT activity in HepG2 cells. CONCLUSION: NAT can inhibit apoptosis in HepG2 cells.