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In ZnO gas sensors, donor defects (such as zinc interstitials and oxygen vacancies) are considered active sites for the chemical adsorption and ionization of oxygen on the surface of ZnO, which can significantly enhance the sensor's response. However, the influence of the surface microstructure and phase boundaries of ZnO nanoparticles on the chemical adsorption and ionization of surface oxygen has rarely been explored. In this study, we developed a mixed-phase ZnO nanoparticle gas sensor with a rich phase boundary showing 198-50 ppm improvement in response to triethylamine at 340 °C. This is attributed to the generation of defects originating from lattice mismatch at the ZnO - zincite phase boundaries, which providing more active sites for adsorption of oxygen and triethylamine molecules. This work demonstrates a feasible method of combining surface microstructure regulation with pyrolysis strategies to develop ZnO sensors with significantly enhanced gas response performance.
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Galvanic replacement reaction (GRR) leverages the difference in metal reduction potentials to regulate the structure of nanomaterials. The crucial aspect of constructing highly active catalysts lies in the precise manipulation of both the oxidative dissolution of sacrificial template metals and reductive deposition of alternate metals. Herein, we investigated the morphological transformation of metal Ni as a sacrificial template in the presence of different amounts of H2PtCl6 solution and the Pt4+ substitution of Ni to achieve the redistribution of elements on the catalyst surface, which provides superior performance in both the methanol oxidation reaction (MOR) and hydrogen evolution reaction (HER). The uniform distribution of Pt on a three-dimensional transition metal Ni substrate allows for the complete exposure of the noble metal to the catalyst surface. This distribution increases the reaction area, facilitating easy access for reactants and promoting electron transfer. Meanwhile, Pt (1.39 Å) has a larger atomic radius compared to Ni (1.24 Å), and the substitution reaction in the transition metal phase induces strong compressive strain, which effectively regulates the electronic structure of Ni.
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Photocatalysts can absorb light and activate molecular O2 under mild conditions, but the generation of unsuitable reactive oxygen species often limits their use in synthesizing fine chemicals. To address this issue, we disperse 1 wt% copper on tungsten trioxide (WO3) support to create an efficient catalyst for selective oxidative coupling of aromatic amines to imines under sunlight irradiation at room temperature. Copper consists of a metallic copper core and an oxide shell. Experimental and density functional theory calculations have confirmed that Cu2O is the primary activation site. Under λ < 475 nm, the light excites electrons of the valence bands in Cu2O and WO3, which activate O2 to superoxide radical â¢O2-. Then rapidly transforms into oxygen adatoms (â¢O) and oxygen anion radicals (â¢O-) species on the surface of Cu2O. Simultaneously, it is captured by holes in the WO3 valence band to generate singlet oxygen (1O2). â¢O bind to 1O2 promoting the coupling reaction of amines. When λ > 475 nm, intense light absorption due to the localized surface plasmon resonance excites numerous electrons in Cu to promote the oxidative coupling with the adsorbed O2. This study presents a promising approach towards the design of high-performance photocatalysts for solar energy conversion and environmentally-friendly oxidative organic synthesis.
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Carbohydrazide electrooxidation reaction (COR) is a potential alternative to oxygen evolution reaction in water splitting process. However, the sluggish kinetics process impels to develop efficient catalysts with the aim of the widespread use of such catalytic system. Since COR concerns the adsorption/desorption of reactive species on catalysts, the electronic structure of electrocatalyst can affect the catalytic activity. Interface charge distribution engineering can be considered to be an efficient strategy for improving catalytic performance, which facilitates the cleavage of chemical bond. Herein, highly dispersed Pd nanoparticles on CeO2 /C catalyst are prepared and the COR catalytic performance is investigated. The self-driven charge transfer between Pd and CeO2 can form the local nucleophilic and electrophilic region, promoting to the adsorption of electron-withdrawing and electron-donating group in carbohydrazide molecule, which facilitates the cleavage of C-N bond and the carbohydrazide oxidation. Due to the local charge distribution, the Pd-CeO2 /C exhibits superior COR catalytic activity with a potential of 0.27â V to attain 10â mA cm-2 . When this catalyst is used for energy-efficient electrolytic hydrogen production, the carbohydrazide electrolysis configuration exhibits a low cell voltage (0.6â V at 10â mA cm-2 ). This interface charge distribution engineering can provide a novel strategy for improving COR catalytic activity.
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Engineering heterostructures with a unique surface/interface structure is one of the effective strategies to develop highly active noble-metal-free catalysts for the oxygen evolution reaction (OER), because the surface/interface of catalysts is the main site for the OER. Herein, we design a coralloid NiMo(Fe)-20 catalyst with a crystalline-amorphous interface through combining a hydrothermal method and an Fe-induced surface reconfiguration strategy. That is, after Fe3+ impregnation treatment, the Ni(OH)2-NiMoO4 pre-catalyst with a complete crystalline surface is restructured into a trimetallic heterostructure with a crystalline-amorphous interface, which facilitates mass diffusion and charge transfer during the OER. As expected, self-supported NiMo(Fe)-20 exhibits excellent electrocatalytic water oxidation performance (overpotential: η-10 = 220 mV, η-100 = 239 mV) in the alkaline electrolyte, and its electrocatalytic performance hardly changes after maintaining the current density of 50 mA cm-2 for 10 hours. Furthermore, nickel foam (NF) supported commercial Pt/C and self-supported NiMo(Fe)-20 served as the cathode and anode of the Pt/CâNiMo(Fe)-20 electrolyzer, respectively, which exhibits a lower cell voltage (E-100 = 1.53 V) than that of the Pt/CâRuO2 electrolyzer (E-100 = 1.58 V) assembled with noble metal-based catalysts. The enhanced electrocatalytic performance of the NiMo(Fe)-20 catalyst is mainly attributed to the synergistic effect between the crystalline-amorphous interface and the coralloid trimetallic heterostructure.
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Surface oxygen vacancy (OV) plays a pivotal role in the activation of molecular oxygen and separation of electrons and holes in photocatalysis. Herein, carbonaceous materials-modified MoO2 nanospheres with abundant surface OVs (MoO2/C-OV) were successfully synthesized via glucose hydrothermal processes. In situ introduction of carbonaceous materials triggered a reconstruction of the MoO2 surface, which introduced abundant surface OVs on the MoO2/C composites. The surface oxygen vacancies on the obtained MoO2/C-OV were confirmed via electron spin resonance spectroscopy (ESR) and X-ray photoelectron spectroscopy (XPS). The surface OVs and carbonaceous materials boosted the activation of molecular oxygen to singlet oxygen (1O2) and superoxide anion radical (â¢O2-) in selectively photocatalytic oxidation of benzylamine to imine. The conversion of benzylamine was 10 times that of pristine MoO2 nanospheres with a high selectivity under visible light irradiation at 1 atm air pressure. These results open an avenue to modify Mo-based materials for visible light-driven photocatalysis.
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Almost all cellular activities depend on protein folding, signaling complex assembly/disassembly, and epigenetic regulation. One of the most important regulatory mechanisms responsible for controlling these cellular processes is dynamic protein phosphorylation/dephosphorylation. Alterations in phosphorylation networks have major consequences in the form of disorders, including cancer. Many signaling cascades, including the target of rapamycin (TOR) signaling, are important participants in the cell cycle, and dysregulation in their phosphorylation/dephosphorylation status has been linked to malignancies. As a TOR signaling regulator, protein phosphatase 2A (PP2A) is responsible for most of the phosphatase activities inside the cells. On the other hand, TOR signaling pathway regulator (TIPRL) is an essential PP2A inhibitory protein. Many other physiological roles have also been suggested for TIPRL, such as modulation of TOR pathways, apoptosis, and cell proliferation. It is also reported that TIPRL was increased in various carcinomas, including non-small-cell lung carcinoma (NSCLC) and hepatocellular carcinomas (HCC). Considering the function of PP2A as a tumor suppressor and also the effect of the TIPRL/PP2A axis on apoptosis and proliferation of cancer cells, this review aims to provide a complete view of the role of TIPRL in cancer development in addition to describing TIPRL/PP2A axis and its epigenetic regulation.
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The interfacial interaction including chemical bonding or electron transfer and even physisorption in composite electrocatalysts has a considerable effect on electrocatalytic oxidation reaction. Herein, we report a tremendously enhanced catalytic activity and excellent durability for the ethanol electro-oxidation reaction in NiMoO4-C-supported Pd composites (Pd/NiMoO4-C) compared to the commercial Pd/C (10%) catalyst. The X-ray powder diffraction, transmission electron microscopy, and X-ray photoelectron spectroscopy measurements disclose that the strong electron transfer between NiMoO4 nanorods and Pd nanoparticles likely induces the formation of more electrochemical active centers and improves the adsorption-desorption capacity of reactants and corresponding intermediates. In addition, the Pd/NiMoO4-C composite exhibits superior specific activity for ethanol oxidation compared to the Pd/NiMoO4 catalyst with physically incorporated carbon black, which further reveals that the stronger anchoring effect between Pd and C and higher electrical conductivity in Pd/NiMoO4-C composites are also conducive to promote the ethanol oxidation reaction. These discoveries provide an effective and simple method for the design of advanced electrocatalysts and provide more insights into optimizing the electronic interaction between the catalyst and support in general.
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Here a facile four-electrode electrolysis system is firstly applied to synthesize a CuOx/graphene hybrid. The exfoliation of graphite via high electrolytic voltage and dissolution of copper via low electrolytic voltage are achieved simultaneously. CuOx/G with the highest content of CuOx shows superior electrocatalytic activity for oxygen reduction to hydrogen peroxide.
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The integration of black phosphorus (BP) with metal phosphides is known to produce high-performance electrocatalysts for oxygen evolution reduction (OER), although increased stability and prevention of the degradation of their lone pairs would be desirable improvements. In this work, cobalt phosphide (CoP)/BP heterostructures were electrochemically synthesized with a two-electrode system, where cobalt ions were generated in situ at a Co anode, and non-aggregated BP nanosheets (NSs) were exfoliated from the bulky BP cathode. With an electrolysis voltage of 30 V, the CoP/BP heterostructure exhibited a superior and stable OER performance (e.g., an overpotential of 300 mV at 10 mA cm-2, which is 41 mV lower than that obtained with a RuO2 catalyst). The CoOx formed in situ during the OER catalysis and remaining CoP synergistically contributed to the enhanced OER performance. The present strategy provides a new electrosynthetic method to prepare stable BP electrocatalysts and also further expands their electrochemical applications.
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As one of the significant serum cytokines, platelet-derived growth factor-BB (PDGF-BB) is a crucial protein biomarker overexpressed in human life-threatening tumors, the sensitive identification and quantification of which are urgently desired but challenging. Herein we report a novel core-shell nanoarchitecture consisting of Cu-based metal-organic frameworks (Cu-MOFs) and covalent organic frameworks (denoted as TpBD-COFs), which was used to prepare an aptasensor for the detection of platelet-derived growth factor-BB (PDGF-BB). The central Cu-MOFs function as signal labels with no need for extra redox media, whereas the porous TpBD serves as the shell to immobilize the PDGF-BB-targeted aptamer strands in abundance via strong interactions involving π-π stacking, electrostatic, and hydrogen bonding interactions. The proposed aptasensor based on Cu-MOF@TpBD can achieve a detection limit as low as 0.034 pg mL-1 within the dynamic detection range from 0.0001 to 60 ng mL-1. The hybridization of MOFs and COFs, together with the immobilization with the specific analyte targeted aptamer, provides a promising and propagable approach to prepare an aptasensor for the simple, sensitive, and selective detection of a specific biomarker in clinical diagnosis.
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Aptámeros de Nucleótidos , Técnicas Biosensibles , Estructuras Metalorgánicas , Becaplermina , Humanos , Límite de Detección , Proteínas Proto-Oncogénicas c-sisRESUMEN
A promising bifunctional catalyst integrating Co@NC units and porous structure carbon nanosheets (Co@NC/NCNS) is in situ prepared by the calcination and subsequent acid etching of a mixture containing metal alkoxide and melamine. Benefiting from the synergism among the active sites and porous structure, the optimal Co@NC/NCNS-800 exhibits superior activity for the ORR/OER.
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BACKGROUND: Somatic mutations are important biomarkers for selecting an optimal targeted therapy and predicting outcomes for non-small-cell lung cancer (NSCLC) patients that are often detected from tissue samples. However, tissue samples are not always readily available from these patients. The exploration of using circulating tumor DNA (ctDNA) to identify somatic mutations offers an alternative source that should be explored. METHODS: In this retrospective study, we included 280 patients diagnosed with adenocarcinoma between 2017 and 2018 in a hospital in eastern China. Tissue or ctDNA was collected, and a wide spectrum of somatic mutations was analyzed by targeted next-generation sequencing platforms. Associations among the mutation status, biomarkers, screening methods, disease stages, and interaction with treatment with overall survival (OS) were investigated. RESULTS: We found that the EGFR L858R mutation was the most frequently identified mutation in adenocarcinoma in this population by both methods, followed by KRAS (p=3.7e-09), PIK3CA (p=5e-04), and HER2 mutations (p=6.3e-03). We observed that EGFR mutations were significantly mutually exclusive with KRAS, HER2, and MET. FGFR1 mutations were significantly more abundantly detected in the ctDNA group. We found an interaction effect between EGFR mutation and target therapies. The ability of the targeted therapy to improve OS in patients with a single EGFR mutation (HR=0.069, p=0.07) approached significance, but this was not the case for the patients with more than one EGFR mutation or without an EGFR mutation (HR=0.813, p=0.725). Furthermore, the effect of chemotherapy was more predominant in the EGFR group in comparison to the control group. CONCLUSION: These findings provide useful information on the distribution of somatic mutations via different screening methods and how this related to the optimal treatment selection in Chinese patients with NSCLC.
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Chronic obstructive pulmonary disease (COPD) is a pathological inflammatory condition of the lungs that is associated with high rates of mortality. Although long non-coding RNAs (lncRNAs) serve a role in lung diseases, their functions in COPD pathogenesis are relatively unknown. The present study aimed to assess the role of differentially expressed lncRNAs in COPD. Expression profile analysis of six lncRNAs in age-matched COPD and non-COPD tissues were conducted. Among the six tested lncRNAs, metastasis-associated in lung adenocarcinoma transcript 1 (MALAT1) was the most consistently overexpressed in COPD lung tissue specimens. To model COPD in vitro, human lung fibroblasts were treated with transforming growth factor-ß (TGF-ß) and MALAT1 was knocked down by small interfering RNA. This promoted cell viability and concurrently inhibited the expression of mesenchymal proteins, fibronectin and α-smooth muscle actin. In COPD, cell senescence is linked to the activation of mammalian target of rapamycin complex 1 (mTORC1). Upon gene silencing of MALAT1 in non-TGF-ß-treated cells, cells demonstrated constitutive activation of mTORC1, which was assessed by the protein expression levels of mTORC1 substrate S6 kinase (S6K1). By contrast, upon MALAT1 silencing in the TGF-ß-treated cells, mTORC1 activation was not suppressed, despite the mesenchymal cell markers protein expression levels being downregulated. Thus, lncRNA MALAT1 may represent a potent biomarker in COPD patients and may act as a target for both diagnostic and therapeutic purposes.
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Therapeutic agents that target both tumor cell and vascular endothelial cell may achieve additional anti-tumor efficacy, particularly in lung cancer due to the critical roles of angiogenesis during lung cancer progression and metastasis. In this work, we showed that pitavastatin, a novel cholesterol-lowering drug, potently inhibited lung cancer cells and angiogenesis. This was achieved by the induction of apoptosis and inhibition of proliferation of lung cancer cells and human lung tumor-associated endothelial cell. Pitavastatin was not only effective to chemo-sensitive but also chemo-resistant lung cancer cells. This was also consistent with the finding that pitavastatin significantly enhanced cisplatin's efficacy in lung cancer xenograft model without causing toxicity in mice. We further showed that pitavastatin inhibited lung tumor angiogenesis in vitro and in vivo through suppressing human lung tumor-associated endothelial cell migration and morphogenesis without affecting adhesion. Mechanistically, we showed that pitavastatin acted on lung cancer cells and human lung tumor-associated endothelial cell through suppressing prenylation-dependent Ras/Raf/MEK and PI3K/Akt/mTOR signaling. Our work is the first to demonstrate the inhibitory effects of pitavastatin on Ras-mediated signaling. Our findings provide pre-clinical evidence to repurpose pitavastatin for the treatment of lung cancer.
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Biomarcadores de Tumor/metabolismo , Colesterol/metabolismo , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Neoplasias Pulmonares/tratamiento farmacológico , Neovascularización Patológica/tratamiento farmacológico , Prenilación , Quinolinas/farmacología , Animales , Apoptosis , Biomarcadores de Tumor/genética , Proliferación Celular , Humanos , Inhibidores de Hidroximetilglutaril-CoA Reductasas/farmacología , Neoplasias Pulmonares/irrigación sanguínea , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patología , MAP Quinasa Quinasa 1/genética , MAP Quinasa Quinasa 1/metabolismo , Ratones , Ratones SCID , Fosfatidilinositol 3-Quinasas/genética , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/genética , Proteínas Proto-Oncogénicas c-akt/metabolismo , Proteínas Proto-Oncogénicas c-raf/genética , Proteínas Proto-Oncogénicas c-raf/metabolismo , Serina-Treonina Quinasas TOR/genética , Serina-Treonina Quinasas TOR/metabolismo , Células Tumorales Cultivadas , Ensayos Antitumor por Modelo de Xenoinjerto , Proteínas ras/genética , Proteínas ras/metabolismoRESUMEN
Invasive mucinous adenocarcinoma of the lung (IMA), a mucinous variant of lung adenocarcinoma, is strongly linked with a worse prognosis. Therefore, a deeper understanding about its molecular mechanism may conduce to a promising IMA therapy. Long non-coding RNAs (lncRNAs) have recently caught great attention for their crucial roles in diverse diseases regarding tumor initiation and progression. However, the potential role of the lncRNA HOXC-AS3 IMA is not well established. Hence, the purpose of present study is to manifest HOXC-AS3-regulated inner mechanism in IMA development. It revealed that HOXC-AS3 was highly expressed in IMA cells. Additionally, it was identified that the significant down-regulation of HOXC-AS3 obstructed cell proliferation and migration in IMA. As far as mechanism is concerned, it found that HOXC-AS3 recruited FUS to stabilize FOXM1 mRNA, accelerating IMA progression. Taken together, these data suggested that HOXC-AS3 may be recognized as a novel therapeutic target for patients with IMA or at least offer new views for molecular therapy.
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Adenocarcinoma del Pulmón/genética , Adenocarcinoma del Pulmón/patología , Adenocarcinoma Mucinoso/genética , Adenocarcinoma Mucinoso/patología , Progresión de la Enfermedad , Proteína Forkhead Box M1/metabolismo , ARN Largo no Codificante/metabolismo , Proteína FUS de Unión a ARN/metabolismo , Apoptosis/genética , Línea Celular Tumoral , Movimiento Celular/genética , Proliferación Celular/genética , Proteína Forkhead Box M1/genética , Regulación Neoplásica de la Expresión Génica , Humanos , Invasividad Neoplásica , Unión Proteica , Estabilidad del ARN , ARN Largo no Codificante/genética , ARN Mensajero/genética , ARN Mensajero/metabolismoRESUMEN
BACKGROUND: In order to overcome the problems associated with the drainage of single-incision thoracoscopic surgery, we investigated the efficiency of applying an 8-Fr pigtail catheter in addition to the conventional 26-Fr chest tube. METHODS: This prospective study includes 88 consecutive patients who underwent single-incision thoracoscopic lobectomy between July 2017 and March 2018. Patients were treated either with (smaller pigtail group) or without (larger drain group) 8-Fr pigtail catheter in addition to conventional 26-Fr chest tube. Post-operative recovery was assessed by analysing the post-operative drainage volume on the first 2 days, the duration (days) of drainage, re-intubation after 2 weeks, air leak time, length of stay, subcutaneous emphysema, pleural effusion after 2 weeks and pain score. RESULTS: The patients in the pigtail tube group had a significantly shorter drainage time and higher drainage volume on the first 2 days than those in the larger drain group. The percentage of patients that developed pleural effusion after 2 weeks was 4.54% in the smaller pigtail group and 25% in the larger drain group (P = 0.007). The pain score in the smaller pigtail tube group decreased significantly on the third day after surgery compared with larger drain group (P < 0.001). There were no significant differences between the two groups in the air leak time, subcutaneous emphysema, wound healing and pain score on the first day. CONCLUSION: Application of 8-Fr pigtail catheter after single-incision thoracoscopic lobectomy for primary lung cancer can accelerate the post-operative recovery of patients.
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Drenaje/instrumentación , Neoplasias Pulmonares/cirugía , Derrame Pleural/terapia , Neumonectomía/métodos , Complicaciones Posoperatorias/terapia , Toracoscopía , Anciano , Catéteres , Tubos Torácicos , Diseño de Equipo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Estudios RetrospectivosRESUMEN
BACKGROUND: More and more patients with small pulmonary nodules (SPN) can be found along with the developing of chest low-dose computed tomography (LDCT). With current examinations not all the SPN can be diagnosed to be benign or malignant and not all the malignant nodules can be diagnosed to be lymphatic metastasis. We need to study the correlation between plasma D-dimer count of patients before surgery with pathology features of non-small cell lung cancer (NSCLC). METHODS: The study comprised 567 highly suspected lung cancer patients. Preoperative plasma D-dimer were qualified, and the relationship between plasma D-dimer with pathology features including benign or malignant nodules, tumor size and involvement of lymph nodes was examined using Kruskal-Wallis test and Spearman correlation coefficients. RESULTS: The median plasma D-dimer values were statistically higher in NSCLC patients than in those who suffered from benign lung nodules (P<0.001). The median plasma D-dimer values in NSCLC patients with malignant lymph nodes were statistically higher than in those without malignant lymph nodes (P<0.001). An obvious relationship was observed between elevated D-dimer with number of malignant lymph nodes involvement and tumer size. An obvious relationship was observed between elevated D-dimer (>112.5 ng/mL) and malignant lymph node involvement in stage T1 lung cancer. CONCLUSIONS: The plasma D-dimer maybe useful for early diagnosis, staging and prognosis of the patients with NSCLC. The plasma D-dimer can be one of the indicator to identify what kind of patients need mediastinal lymph node cleaning.
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Carcinoma de Pulmón de Células no Pequeñas/sangre , Productos de Degradación de Fibrina-Fibrinógeno/metabolismo , Neoplasias Pulmonares/sangre , Adulto , Anciano , Carcinoma de Pulmón de Células no Pequeñas/patología , Femenino , Humanos , Neoplasias Pulmonares/patología , Metástasis Linfática , Masculino , Persona de Mediana Edad , Estudios RetrospectivosRESUMEN
A metal-free carbon quantum dot (CQD)/graphene hybrid was in situ synthesized through a simple novel two-step procedure. The hybrid showed superior HER and OER activity attributed to synergistic effects between the defect-rich CQDs and conducting graphene support.
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Pd-Cu alloys with adjustable morphologies were synthesized and examined as nanocatalysts for electro-oxidation of ethylene glycol. The Cu2+ can effectively adjust the morphology of the Pd-Cu alloys. The as-prepared super-branched Pd-Cu alloys exhibit a greatly enhanced catalytic activity toward ethylene glycol electro-oxidation, because the super-branched structure creates abundant surface active sites and a suitable electronic landscape benefiting from alloying Pd with Cu.