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1.
Proc Natl Acad Sci U S A ; 121(8): e2311326121, 2024 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-38349884

RESUMEN

Photoelectrochemical (PEC) coupling of CO2 and nitrate can provide a useful and green source of urea, but the process is affected by the photocathodes with poor charge-carrier dynamics and low conversion efficiency. Here, a NiFe diatomic catalysts/TiO2 layer/nanostructured n+p-Si photocathode is rationally designed, achieving a good charge-separation efficiency of 78.8% and charge-injection efficiency of 56.9% in the process of PEC urea synthesis. Compared with the electrocatalytic urea synthesis by using the same catalysts, the Si-based photocathode shows a similar urea yield rate (81.1 mg·h-1·cm-2) with a higher faradic efficiency (24.2%, almost twice than the electrocatalysis) at a lower applied potential under 1 sun illumination, meaning that a lower energy-consumption method acquires more aimed productions. Integrating the PEC measurements and characterization results, the synergistic effect of hierarchical structure is the dominating factor for enhancing the charge-carrier separation, transfer, and injection by the matched band structure and favorable electron-migration channels. This work provides a direct and efficient route of solar-to-urea conversion.

2.
Angew Chem Int Ed Engl ; 62(24): e202304079, 2023 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-37084003

RESUMEN

Photoelectrochemical lithium (Li) extraction can be expected to provide a useful recycle of Li+ from waste Li-containing battery, but the process is limited by the photocathodes with poor Li+ absorption and low yield rate. Here, we have designed a hierarchical silicon (Si)-based photocathode with mixed-phase tungsten oxide (WO3 ) cocatalysts for photoelectrochemical Li extraction under 1 sun illumination, achieving a high Li yield rate of ≈223.0 µg cm-2 h-1 and an excellent faradaic efficiency of 91.9 % at 0.0817 V versus Li0/+ redox couple. The WO3 cocatalysts with the mixture of amorphous and crystalline phase accelerates the Li+ insertion and precipitation and enriches the concentration of Li+ at the photocathode surface. This robust photoelectrochemical Li extraction system provides a new insight on designing green and efficient route for cyclic utilization of Li resources in the sustainable energy field.

3.
Angew Chem Int Ed Engl ; 62(33): e202305447, 2023 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-37337852

RESUMEN

Electrocatalytic urea synthesis via coupling N2 and CO2 provides an effective route to mitigate energy crisis and close carbon footprint. However, the difficulty on breaking N≡N is the main reason that caused low efficiencies for both electrocatalytic NH3 and urea synthesis, which is the bottleneck restricting their industrial applications. Herein, a new mechanism to overcome the inert of the nitrogen molecule was proposed by elongating N≡N instead of breaking N≡N to realize one-step C-N coupling in the process for urea production. We constructed a Zn-Mn diatomic catalyst with axial chloride coordination, Zn-Mn sites display high tolerance to CO poisoning and the Faradaic efficiency can even be increased to 63.5 %, which is the highest value that has ever been reported. More importantly, negligible N≡N bond breakage effectively avoids the generation of ammonia as intermediates, therefore, the N-selectivity in the co-electrocatalytic system reaches100 % for urea synthesis. The previous cognition that electrocatalysts for urea synthesis must possess ammonia synthesis activity has been broken. Isotope-labelled measurements and Operando synchrotron-radiation Fourier transform infrared spectroscopy validate that activation of N-N triple bond and nitrogen fixation activity arise from the one-step C-N coupling process of CO species with adsorbed N2 molecules.

4.
Small ; 16(14): e1906867, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32162756

RESUMEN

Cobalt pnictides show good catalytic activity and stability on oxygen evolution reaction (OER) behaviors in a strong alkaline solution. Identifying the intrinsic composition/structure-property relationship of the oxide layer on the cobalt pnictides is critical to design better and cheaper electrocatalysts for the commercial viability of OER technologies. In this work, the restructured oxide layer on the cobalt pnictides and its effect on the activity and mechanism for OER is systematically analyzed. In-situ electrochemical impedance spectroscopy (EIS) and near edge x-ray absorption fine structure (NEXAFS) spectra indicate that a higher OER performance of cobalt pnictides than Co3 O4 is attributed to the more structural disorder and oxygen defect sites in the cobalt oxide layer evolved from cobalt pnictides. Using angle resolved x-ray photoelectron spectroscopy (AR-XPS) further demonstrates that the oxygen defect sites mainly concentrate on the subsurface of cobalt oxide layer. The current study demonstrated promising opportunities for further enhancing the OER performance of cobalt-based electrocatalysts by controlling the subsurface defects of the restructured active layer.

5.
J Cell Biochem ; 120(4): 6290-6298, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30378158

RESUMEN

YWHAZ has been suggested to as an oncogene in various human malignancies, including non-small-cell lung cancer (NSCLC). Our study presents more evidence to confirm the clinical significance and biological function of YWHAZ in NSCLC. In our results, YWHAZ was upregulated in lung squamous cell carcinoma tissues and lung adenocarcinoma tissues through analyzing The Cancer Genome Atlas (TCGA) database, and confirmed high levels of YWHAZ messenger RNA and protein in lung squamous cell carcinoma tissues and lung adenocarcinoma tissues through quantitative real-time polymerase chain reaction and immunohistochemistry. Moreover, YWHAZ overexpression was correlated with advanced clinical stage, more lymph node metastasis and present distant metastasis in NSCLC patients. Survival analysis indicated that high level of YWHAZ protein expression was associated with short overall survival time in NSCLC patients, and YWHAZ expression was independent prognostic factors for overall survival in NSCLC patients. Moreover, Silencing of YWHAZ expression represses NSCLC cell migration and invasion. In conclusion, YWHAZ is a credible prognostic biomarker, and may be a therapeutic target in NSCLC.


Asunto(s)
Proteínas 14-3-3/genética , Proteínas 14-3-3/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/patología , Neoplasias Pulmonares/patología , Regulación hacia Arriba , Células A549 , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Metástasis Linfática , Masculino , Estadificación de Neoplasias , Pronóstico , Análisis de Supervivencia
6.
Angew Chem Int Ed Engl ; 58(51): 18604-18609, 2019 Dec 16.
Artículo en Inglés | MEDLINE | ID: mdl-31535425

RESUMEN

The (photo)electrochemical N2 reduction reaction (NRR) provides a favorable avenue for the production of NH3 using renewable energy in mild operating conditions. Understanding and building an efficient catalyst with high NH3 selectivity represents an area of intense interest for the early stages of development for NRR. Herein, we introduce a CoOx layer to tune the local electronic structure of Au nanoparticles with positive valence sites for boosting conversion of N2 to NH3 . The catalysts, possessing high average oxidation states (ca. 40 %), achieve a high NH3 yield rate of 15.1 µg cm-2 h-1 and a good faradic efficiency of 19 % at -0.5 V versus reversible hydrogen electrode. Experimental results and simulations reveal that the ability to tune the oxidation state of Au enables the control of N2 adsorption and the concomitant energy barrier of NRR. Altering the Au oxidation state provides a unique strategy for control of NRR in the production of valuable NH3 .

7.
Nanotechnology ; 28(5): 055403, 2017 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-28029104

RESUMEN

An anodized TiO2 interconnected network was fabricated and utilized as a mesoporous scaffold and electron transporter in perovskite solar cells. By modifying the synthesis parameters, the morphological features of the interconnected TiO2 nanostructures can be widely tuned and precisely controlled. The functional properties of the anodized TiO2 network are found to be severely influenced by morphology as well as the extent of oxidation. The device with the optimized TiO2 network exhibits superior electron extraction and transferability, resulting in conspicuous enhancement of the photocurrent and power conversion efficiency (PCE). This work proposes a promising and facile method for improving the performance of perovskite solar cells.

8.
ChemSusChem ; : e202301526, 2024 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-38538545

RESUMEN

The amount of global hybrid-electric and all electric vehicle has increased dramatically in just five years and reached an all-time high of over 10 million units in 2022. A good deal of waste lithium (Li)-containing batteries from dead vehicles are invaluable unconventional resources with high usage of Li. However, the recycle of Li by green approaches is extremely inefficient and rare from waste batteries, giving rise to severe environmental pollutions and huge squandering of resources. Thus, in this mini review, we briefly summarized a green and promising route-photoelectrochemical (PEC) technology for extracting the Li from the waste lithium-containing batteries. This review first focuses on the critical factors of PEC performance, including light harvesting, charge-carrier dynamics, and surface chemical reactions. Subsequently, the conventional and PEC technologies applying in the area of Li recovery processes are analyzed and discussed in depth, and the potential challenges and future perspective for rational and healthy development of PEC Li extraction are provided positively.

9.
Front Plant Sci ; 14: 1166803, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37469772

RESUMEN

Endophytic fungi can promote host plant growth, enhance antioxidant defense enzyme activity, and induce the biosynthesis and accumulation of secondarymetabolites. Therefore, using endophytic fungi to improve the quality and yield of medicinal plants or important crops is an effective means of regulation. Colletotrichum sp. AP12 has been reported to produce andrographolide compounds (ADCs). This study aimed to investigate the effects of AP12 and its elicitors on the growth, defense enzyme activity, accumulation, and transcription levels of key genes in Andrographis paniculata (Burm. f.) Nees (A. paniculata). Using fermentation method to prepare AP12 into the inactivated fermentation solution (IFS), fermentation solution (FS), inactivated mycelium solution (IMS), and mycelium solution (MS), and the results showed that all four fungal elicitor components (ECs) could promote A. paniculata growth, enhance antioxidant defense enzymes, and increase ADC content and yield, especially the IMS group that had the highest leaf area, whole plant dry weight, superoxide dismutase (SOD), catalase (CAT) enzyme activities, total lactone contents, and yields, which were 2.37-, 1.60-, 2.20-, 3.27-, 1.59-, and 2.65-fold of the control, respectively. The 14-deoxyandrographolide (NAD) in the host irrigated with MS was 3.35-fold that of the control. In addition, AP12-infected A. paniculata sterile seedlings could significantly increase ADC content and expression levels of key enzyme genes, especially on day 12, when the total lactone content of the host reached 88.881± 5.793 mg/g DW, while on day 6, CPS gene expression level reached 10.79-fold that of the control, in turn promoting the biosynthesis and accumulation of andrographolide. In conclusion, the endophytic fungus AP12 is beneficial to the growth and secondary metabolism of A. paniculata, which is helpful for the cultivation and application of the biological bacterial fertilizer in A. paniculata, providing a theoretical and research basis for the use of endophytic fungi as a microbial resource to improve the quality and yield of medicinal plants.

10.
JACS Au ; 3(2): 592-602, 2023 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-36873698

RESUMEN

Enhancing charge-carrier dynamics is imperative to achieve efficient photoelectrodes for practical photoelectrochemical devices. However, a convincing explanation and answer for the important question which has thus far been absent relates to the precise mechanism of charge-carrier generation by solar light in photoelectrodes. Herein, to exclude the interference of complex multi-components and nanostructuring, we fabricate bulky TiO2 photoanodes through physical vapor deposition. Integrating photoelectrochemical measurements and in situ characterizations, the photoinduced holes and electrons are transiently stored and promptly transported around the oxygen-bridge bonds and 5-coordinated Ti atoms to form polarons on the boundaries of TiO2 grains, respectively. Most importantly, we also find that compressive stress-induced internal magnetic field can drastically enhance the charge-carrier dynamics for the TiO2 photoanode, including directional separation and transport of charge carriers and an increase of surface polarons. As a result, bulky TiO2 photoanode with high compressive stress displays a high charge-separation efficiency and an excellent charge-injection efficiency, leading to 2 orders of magnitude higher photocurrent than that produced by a classic TiO2 photoanode. This work not only provides a fundamental understanding of the charge-carrier dynamics of the photoelectrodes but also provides a new paradigm for designing efficient photoelectrodes and controlling the dynamics of charge carriers.

11.
Adv Mater ; 35(21): e2211894, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36905214

RESUMEN

As a widely used commodity chemical, ammonia is critical for producing nitrogen-containing fertilizers and serving as the promising zero-carbon energy carrier. Photoelectrochemical nitrogen reduction reaction (PEC NRR) can provide a solar-powered green and sustainable route for synthesis of ammonia (NH3 ). Herein, an optimum PEC system is reported with an Si-based hierarchically-structured PdCu/TiO2 /Si photocathode and well-thought-out trifluoroethanol as the proton source for lithium-mediated PEC NRR, achieving a record high NH3 yield of 43.09 µg cm-2 h-1 and an excellent faradaic efficiency of 46.15% under 0.12 MPa O2 and 3.88 MPa N2 at 0.07 V versus lithium(0/+) redox couple (vs Li0/+ ). PEC measurements coupled with operando characterization reveal that the PdCu/TiO2 /Si photocathode under N2 pressures facilitate the reduction of N2 to form lithium nitride (Li3 N), which reacts with active protons to produce NH3 while releasing the Li+ to reinitiate the cycle of the PEC NRR. The Li-mediated PEC NRR process is further enhanced by introducing small amount of O2 or CO2 under pressure by accelerating the decomposition of Li3 N. For the first time, this work provides mechanistic understanding of the lithium-mediated PEC NRR process and opens new avenues for efficient solar-powered green conversion of N2 -to-NH3 .

12.
Mol Biol Rep ; 39(10): 9733-9, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22723001

RESUMEN

Fatty acid synthase (FASN) overexpression has also been associated with a variety of human malignancies including tumor progression, aggressiveness, and metastasis. To investigate the role of FASN expression in esophageal cancer, we evaluated 60 cases of squamous cell carcinoma, 20 cases of adenocarcinoma, and 10 cases of normal esophageal tissues. We found that FASN was detected in 95 % human squamous cell carcinoma, and in 90 % human adenocarcinoma samples. However, all cases of normal esophageal epithelium did not express the protein of FASN. Further, to investigate the role of FASN in tumorigenesis and development, we analyze the growth and migration by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), colony formation and wound healing assay. We found that inhibition of FASN expression in TE13 cells by RNAi suppressed the growth of cells. Decreased FASN expression mitigated the migration of TE13 cells. These studies demonstrated the functional importance of FASN in esophageal tumorigenesis, and suggested that inhibiting FASN might be applied to treat esophageal cancer.


Asunto(s)
Adenocarcinoma/enzimología , Carcinoma de Células Escamosas/enzimología , Neoplasias Esofágicas/enzimología , Acido Graso Sintasa Tipo I/metabolismo , Expresión Génica , Línea Celular Tumoral , Movimiento Celular , Proliferación Celular , Esófago/enzimología , Esófago/patología , Acido Graso Sintasa Tipo I/genética , Femenino , Técnicas de Silenciamiento del Gen , Humanos , Masculino , Persona de Mediana Edad , Membrana Mucosa/enzimología , Interferencia de ARN
13.
ACS Appl Mater Interfaces ; 14(7): 8955-8962, 2022 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-35147408

RESUMEN

The rechargeable zinc-iodine (Zn-I2) battery is a promising energy-storage system due to its low cost and good security, but the practical use of the battery is largely constrained by the shuttle effect and high dissolvability of iodides. Here a multifunctional iodine host, constructed with nitrogen-doped porous carbon nanocages (NCCs) by the polymerization carbonization activation method, is exploited to improve the electrochemical performance and lifespan of the Zn-I2 battery, achieving a high specific capacity of 259 mAh g-1, a good rate performance (maintaining 50.6% expanding 50 times), and a high cycle stability (retention of 100% after 1000 cycles). On the basis of the experimental results and theoretical calculations, NCCs via the introduction of N doping and nanosized porous structure can simultaneously provide rich and robust anchoring and catalytic sites to carry out the electrostatic adsorption of iodides and facilitate the reversible conversion between iodine and iodides. This work shows a novel and efficient strategy to develop high-performance and long-life Zn-I2 batteries.

14.
Front Microbiol ; 13: 819770, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35295309

RESUMEN

Endophytic fungi of medicinal plants are abundant, and their metabolites often have antioxidant, antibacterial, and antitumor effects and can produce secondary metabolites identical or similar to those of their hosts, which can mitigate the problem of insufficient supply of medicinal plants. In this study, we screened endophytic fungi for strains that produce the same diterpene lactones as Andrographis paniculata based on their biological activity. Firstly, the dominant group of endophytic fungi of Andrographis paniculata was screened and pathogenicity was studied using Koch's rule. Secondly, DPPH, ABTS, OH, PTIO radical scavenging, and FRAP assays were used to detect the antioxidant activity of the extracellular extracts of the strains, and total phenol and total flavonoid contents of the strains with high antioxidant capacity were determined. S. aureus, B. subtilis, E. coli, and P. aeruginosa were used to determine the antibacterial activity of the mycelial extracts of the strains. Finally, the secondary metabolites of the mycelial extracts of the strains were examined by high-performance liquid chromatography. The results showed that 32 strains of Andrographis paniculata were relatively isolated > 70% and non-pathogenic. Extracellular extracts of strains AP-1 and AP-4 showed vigorous antioxidant activity, and AP-4, AP-12, AP-47, and AP-48 showed antibacterial activity against four strains of bacteria. The HPLC results indicated that the mycelial extracts of AP-4 and AP-12 contained diterpene lactones. The two endophytic fungi were recognized as Colletotrichum sp. The study successfully obtained diterpene lactones from the endophytic fungus of Andrographis paniculata and confirmed the feasibility of using endophytic fungal strains to produce active substances consistent with the host. It was also useful for exploring endophytic fungi and medicinal plants. The relationship provides theoretical guidance.

15.
Nat Commun ; 13(1): 5337, 2022 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-36088335

RESUMEN

Electrocatalytic urea synthesis emerged as the promising alternative of Haber-Bosch process and industrial urea synthetic protocol. Here, we report that a diatomic catalyst with bonded Fe-Ni pairs can significantly improve the efficiency of electrochemical urea synthesis. Compared with isolated diatomic and single-atom catalysts, the bonded Fe-Ni pairs act as the efficient sites for coordinated adsorption and activation of multiple reactants, enhancing the crucial C-N coupling thermodynamically and kinetically. The performance for urea synthesis up to an order of magnitude higher than those of single-atom and isolated diatomic electrocatalysts, a high urea yield rate of 20.2 mmol h-1 g-1 with corresponding Faradaic efficiency of 17.8% has been successfully achieved. A total Faradaic efficiency of about 100% for the formation of value-added urea, CO, and NH3 was realized. This work presents an insight into synergistic catalysis towards sustainable urea synthesis via identifying and tailoring the atomic site configurations.

16.
Adv Mater ; 34(27): e2105320, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35472674

RESUMEN

The nucleophile oxidation reaction (NOR) is of enormous significance for organic electrosynthesis and coupling for hydrogen generation. However, the nonuniform NOR mechanism limits its development. For the NOR, involving electrocatalysis and organic chemistry, both the electrochemical step and non-electrochemical process should be taken into account. The NOR of nickel-based hydroxides includes the electrogenerated dehydrogenation of the Ni2+ -OH bond and a spontaneous non-electrochemical process; the former determines the electrochemical activity, and the nucleophile oxidation pathway depends on the latter. Herein, the space-confinement-induced synthesis of Ni3 Fe layered double hydroxide intercalated with single-atom-layer Pt nanosheets (Ni3 Fe LDH-Pt NS) is reported. The synergy of interlayer Pt nanosheets and multiple defects activates Ni-OH bonds, thus exhibiting an excellent NOR performance. The spontaneous non-electrochemical steps of the NOR are revealed, such as proton-coupled electron transfer (PCET; Ni3+ -O + X-H = Ni2+ -OH + X• ), hydration, and rearrangement. Hence, the reaction pathway of the NOR is deciphered, which not only helps to perfect the NOR mechanism, but also provides inspiration for organic electrosynthesis.

17.
Zhonghua Zhong Liu Za Zhi ; 32(8): 590-4, 2010 Aug.
Artículo en Zh | MEDLINE | ID: mdl-21122410

RESUMEN

OBJECTIVE: To investigate the expression and clinical significance of mismatch repair genes hMLH1 and hMSH2 in sporadic colorectal carcinoma tissues. METHODS: The expression of hMLH1 and hMSH2 proteins was detected in the 63 sporadic colorectal carcinoma samples by immunohistochemical staining, including tumor tissue, adjacent tissue at 3 cm from the carcinoma, and normal tissue at 10 cm away from the tumor. RESULTS: The positive rate of hMLH1 protein expression in the 63 normal colorectal tissues, adjacent tissues and sporadic colorectal carcinoma tissues was 95.2%, 85.7% and 81.0%, respectively. The positive rate of hMLH1 protein expression was significantly lower in the tumor than in normal colorectal tissues (P < 0.05). The positive rate of hMSH2 protein in the 63 normal colorectal tissues, adjacent tissues and sporadic colorectal carcinoma tissues were 76.2%, 66.7% and 52.4%, respectively. The positive rate of hMSH2 protein expression was significantly lower in the tumor than in normal colorectal tissues (P < 0.01). The positive rate of hMLH1 protein expression was significantly higher in the tumor tissue of patients aged younger than 60 years (100%) than that in patients ≥ 60 years (75.0%, P < 0.05). The positive rate of hMLH1 protein expression in the tumor tissue accompanied by lymphatic metastasis was 50.0%, significantly lower than that (93.3%) in tumors without lymphatic metastasis (P < 0.05). The positive rate of hMSH2 protein expression in the tumor tissue of patients aged younger than 60 years was 80.0%, significantly higher than that (43.8%) in the cases ≥ 60 years (P < 0.05). The positive rate of hMSH2 protein expression in the tumor tissues with invasion reaching to the intestinal serosa (61.5%) was significantly higher than that (37.5%) in the tumors invading to submucosa or muscular layer (P < 0.05). There was a positive correlation between the expressions of hMLH1 and hMSH2 proteins in the sporadic colorectal carcinomas. CONCLUSION: There is a certain loss of expression of hMLH1 and hMSH2 proteins in sporadic colorectal carcinoma, and is correlated with the age of patients, lymphatic metastasis and different depth of cancer invasion. HMLH1 and hMSH2 may be used as a useful laboratory marker in clinical judgement of occurrence and development of sporadic colorectal carcinoma.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/metabolismo , Adenocarcinoma/metabolismo , Neoplasias del Colon/metabolismo , Proteína 2 Homóloga a MutS/metabolismo , Proteínas Nucleares/metabolismo , Neoplasias del Recto/metabolismo , Adenocarcinoma/patología , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Biomarcadores de Tumor/metabolismo , Neoplasias del Colon/patología , Femenino , Humanos , Metástasis Linfática , Masculino , Persona de Mediana Edad , Homólogo 1 de la Proteína MutL , Invasividad Neoplásica , Neoplasias del Recto/patología
18.
Exp Ther Med ; 18(3): 1823-1830, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31410143

RESUMEN

Cervical cancer (CC) is the second most common malignant cancer among women. Gefitinib was one of the first-generation epidermal growth factor receptor-tyrosine kinase inhibitors in clinical trials. However, the underlying mechanism of gefitinib in regulating CC progression remains unknown. In the current study, two CC cell lines, HeLa and Siha, were used to investigate the effects of gefitinib. Cell counting kit-8 assays demonstrated that treatment with gefitinib exerted strong cytotoxicity in HeLa and Siha cells. Flow cytometry was used to examine cell cycle progression and apoptosis. Treatment with gefitinib enhanced the number of cells in the G0/G1 phase and increased apoptosis in HeLa and Siha cells. Furthermore, treatment with gefitinib decreased the protein expression level of Bcl-2 and increased the protein expression level of Bax. Taken together, these results suggest that gefitinib may suppress CC cell proliferation and induce cell cycle arrest and apoptosis. The current study also demonstrated that treatment with gefitinib suppressed epithelial-mesenchymal transition (EMT) as the expression level of the epithelial marker, E-cadherin was increased, while the expression level of the mesenchymal marker, vimentin was decreased. The current study demonstrated that treatment with gefitinib decreased the protein expression levels of phosphorylated-GSK3ß and ß-catenin, which suggests that gefitinib may be a potential novel therapeutic strategy in CC by suppressing the Wnt/ß-catenin signaling pathway and EMT to inhibit tumor metastasis in CC cells. In conclusion, gefitinib may suppress the EMT process during cell invasion and induce cell apoptosis and cell cycle arrest via inhibition of the Wnt/ß-catenin signaling pathway.

19.
Sci Rep ; 9(1): 6652, 2019 04 30.
Artículo en Inglés | MEDLINE | ID: mdl-31040354

RESUMEN

Hepatocellular carcinoma (HCC) is one of the major causes of cancer-related death worldwide. However, the molecular mechanism underlying HCC carcinogenesis remains to be further elucidated. Up-frameshift protein 1 (UPF1) is a RNA/DNA-dependent ATPase and ATP-dependent RNA helicase. Here, we explored the expression and function of UPF1 in HCC. In this study, we demonstrated that UPF1 expression was significantly reduced in hepatocellular carcinoma (HCC) tissues compared with the adjacent normal tissues. And further functional assays revealed that knockdown of UPF1 promoted HCC cells growth and invasion. Furthermore, we found that UPF1 could bind to long non-coding RNA urothelial cancer associated 1 (UCA1) and was negatively correlated with UCA1. UCA1 expression also affected HCC growth and invasion. Knockdown of UCA1 ameliorated the effect of UPF1 knock down on HCC growth and invasion. Knockdown of UPF1 enhances glycolysis in HCC. Taken together, our results provided new insights for finding novel therapeutic targets for hepatocellular carcinoma progression.


Asunto(s)
Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Regulación Neoplásica de la Expresión Génica , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , ARN Helicasas/metabolismo , ARN Largo no Codificante/genética , Transactivadores/metabolismo , Carcinoma Hepatocelular/patología , Línea Celular Tumoral , Proliferación Celular , Técnicas de Silenciamiento del Gen , Silenciador del Gen , Glucólisis , Humanos , Inmunohistoquímica , Neoplasias Hepáticas/patología , Unión Proteica , ARN Helicasas/genética , Transactivadores/genética
20.
Nat Commun ; 9(1): 3572, 2018 09 03.
Artículo en Inglés | MEDLINE | ID: mdl-30177720

RESUMEN

The trade-offs between photoelectrode efficiency and stability significantly hinder the practical application of silicon-based photoelectrochemical devices. Here, we report a facile approach to decouple the trade-offs of silicon-based photocathodes by employing crystalline TiO2 with graded oxygen defects as protection layer. The crystalline protection layer provides high-density structure and enhances stability, and at the same time oxygen defects allow the carrier transport with low resistance as required for high efficiency. The silicon-based photocathode with black TiO2 shows a limiting current density of ~35.3 mA cm-2 and durability of over 100 h at 10 mA cm-2 in 1.0 M NaOH electrolyte, while none of photoelectrochemical behavior is observed in crystalline TiO2 protection layer. These findings have significant suggestions for further development of silicon-based, III-V compounds and other photoelectrodes and offer the possibility for achieving highly efficient and durable photoelectrochemical devices.

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