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1.
Heliyon ; 10(10): e31092, 2024 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-38803866

RESUMEN

This study empirically investigates the crowding effect of Foreign Direct Investment (FDI) on domestic investments in Bangladesh, utilizing annual time series data from 1972 to 2022. Initially, unit root tests are conducted with and without considering structural breaks in the dataset. This study employs the Johansen test of cointegration to investigate the enduring association between the variables and utilizes the Vector Error Correction Model (VECM) to accommodate this relationship over the long term. Following the estimation of the VECM, formulas about the magnitude of the crowding effect (CE) are applied to examine the impact of FDI on domestic investment in Bangladesh. Results indicate that FDI positively influences domestic investments in both the short and long run.

2.
Sci Total Environ ; 921: 171080, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38387581

RESUMEN

Accurately evaluating drought impact on agriculture poses a challenge to regional food security, particularly in compound drought (i.e., meteorological and agricultural drought co-occurring) scenarios. This study presents a novel approach utilizing Vine copula for coupling spatiotemporal features to evaluate drought propagation. Three-dimensional clustering method was employed to identify meteorological and agricultural drought events, which excelled in capturing dynamic evolution characteristics (duration, area, severity, etc.) as well as integrating them into comprehensive meteorological drought intensity (IMD) and agricultural drought intensity (IAD). Through spatiotemporal matching, compound drought events were extracted from the meteorological-agricultural drought event pairs. From compound drought perspective, compound duration (CD) and compound area (CA) were devised to characterize drought propagation potential across time and space. Finally, the Vine copula method was employed to model the interdependence between four key coupling features, namely IMD, IAD, CD, and CA, and evaluate the probability of triggering agricultural drought with different intensity levels. Results showed that CD and CA can respectively characterize the temporal and spatial accumulation scale of drought propagation. At a certain IMD level, CD significantly influences the propagation probability (i.e., "stratification" phenomenon), while CA increases the probability proportionally. Probability evaluation lacking spatiotemporal information may underestimate the likelihood of drought propagation characterized by "low-IMD" but "long-CD" or "large-CA". The four-dimensional Vine copula structure can effectively couple dependence relationships of compound drought characteristics, and exhibits reliable robustness. This research provides stakeholders accurate probabilistic evaluation under compound drought scenarios, offering new insight into drought propagation.

3.
Environ Sci Pollut Res Int ; 30(6): 15861-15880, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36173518

RESUMEN

The ecological protection and high-quality development of the Yellow River Basin have become major national strategies in China. Therefore, reducing carbon emissions in the Yellow River Basin through efficient industrial agglomeration is necessary for achieving the goals of carbon peak by 2030 and carbon neutrality by 2060. The Yellow River Basin is an important base for energy, chemicals, raw materials, and industry in China, making it important to study the effects of different industrial agglomeration types on carbon productivity from the perspective of agglomeration externalities. Therefore, taking 2009-2019 panel data for prefecture-level cities in the Yellow River Basin, this study uses a spatial Durbin model to investigate the spatial spillover effects of industrial agglomeration (i.e., specialized, diversified, and competitive agglomeration) on carbon productivity. Furthermore, the moderating effects of urbanization level and environmental regulation are analyzed. The results reveal, first, the existence of spatial correlation in carbon productivity across different cities in the Yellow River Basin. Second, diversified and competitive agglomeration significantly increase carbon productivity, although competitive agglomeration has beggar-thy-neighbor spillover effects. Meanwhile, the effect of specialized agglomeration is not significant. Third, the effects of different types of industrial agglomeration differ significantly between cities in different locations and with different resource endowments. Fourth, urbanization level and environmental regulation have different moderating effects in the relationship between different types of industrial agglomeration and carbon productivity. These findings provide evidence for further developing rational industrial agglomeration patterns to enhance carbon productivity in the Yellow River Basin.


Asunto(s)
Carbono , Ríos , China , Ciudades , Industrias , Desarrollo Económico
4.
Sci Total Environ ; 840: 156492, 2022 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-35667434

RESUMEN

Vegetation degradation is the key cause of land desertification in arid areas. Water stress is one of the most critical factors leading to vegetation degradation. The water needed for vegetation growth is inseparable from the water cycle processes. It is a new scope to reveal the vegetation water demand mechanisms from the water cycle processes. Water cycle processes in arid inland basins can be conceptually separated as RFA (runoff formation area) and RCA (runoff consumption area). In this study, both the water demand mechanisms of natural vegetation and farmland were discovered by creatively constructing the vegetation water demand route model. The TRB (Tarim River Basin), a typical arid inland basin system that RFA is separated from RCA, is considered as the study area. The tendency and relevance of water cycle factors and NDVI were detected. The dominant factors of vegetation growth were identified. According to the interaction causality of water cycle factors and vegetation, the PLS-SEM (partial least squares structural equation models) were constructed in RFA and RCA. Results displayed that SMroot (root-zone soil moisture), groundwater and precipitation were the dominant water sources for natural vegetation in RFA. The water demand for natural vegetation in RCA mainly came from SMroot and that for farmland mainly came from SMsurf (surface soil moisture). New findings showed that blue and green water circulations were more active in RFA than in RCA. Natural vegetation had better adaptability and resilience to water shortages compared with farmland. The higher effect of vegetation on AET (actual evapotranspiration) denoted the better growth status. It is contributed to the rational utilization of water resources in arid basins.


Asunto(s)
Agua Subterránea , Ciclo Hidrológico , China , Ríos/química , Suelo , Recursos Hídricos
5.
Sci Total Environ ; 819: 153056, 2022 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-35032532

RESUMEN

Improving the adsorption capacity of adsorbents is a good way to boost their desulfurization efficiency. Optimizing the dispersion of metal nanoparticles and enhancing the stability of the metal valence state are essential to maximizing the adsorption capacity of the metal-loaded desulfurization adsorbent. Pistia stratiotes can absorb the Cu in water and evenly disperse it throughout the plant, allowing the production of a highly dispersed Cu(I) adsorbent (PSAC-Cu(I)). During the usage and storage of PSAC-Cu(I), Cu(I) oxidizes to Cu(II) when it comes in contact with oxygen and water, reducing its adsorptive capacity; hence, we modified PSAC-Cu(I) hydrophobically using polydimethylsiloxane (PDMS) to generate PSAC-Cu(I)-P(200). The outcome of the two-month exposure experiments showed that only 4.7% of the Cu(I) of PSAC-Cu(I)-P(200) was oxidized in the humid atmosphere, whereas PSAC-Cu(I) was almost fully oxidized. Moreover, the dibenzothiophene adsorption capacity of PSAC-Cu(I)-P(200) in a model oil with a water concentration of 250 ppmw is 68 mg g-1, which is 1.62 times that of PSAC-Cu(I). When 10 wt% toluene was added to the model oil, the adsorption desulfurization capacity of PSAC-Cu(I)-P(200) decreased to 86.8% of the original. This shows that PSAC-Cu(I)-P(200) has good stability and excellent adsorptive desulfurization performance.


Asunto(s)
Araceae , Nanopartículas del Metal , Adsorción , Agua
6.
Environ Sci Pollut Res Int ; 29(9): 12911-12932, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35031995

RESUMEN

China has been the world's largest emitter of carbon dioxide since 2006. To achieve the goal of carbon neutrality by 2060, social scientists must become involved in China's deep decarbonization process. However, Chinese social scientists have given little attention to climate change in their bibliometric research. Based on the Chinese Social Sciences Citation Index journal catalog of the four essential social sciences, namely, management, economics, politics, and sociology, we used the China National Knowledge Infrastructure database to quantify the extent to which Chinese social scientists are concerned about climate change. The results showed that from 1978 to 2020, 1179 articles on climate change were published in management, economics, politics, and sociology journals, which represented only 26.8% of the 4397 articles published on pollution in the same journals. Politics journals published the most articles (38.76%), while sociology journals published the fewest (2.37%). Thus, Chinese social scientists rarely considered climate change, mainly because this topic remains controversial in some fields and because of the influence of international politics in addition to the promotion and incentive mechanisms for researchers. We analyzed the keywords and evolution of climate change research in the four social sciences and our results show that social scientists should give greater emphasis to climate change in their research.


Asunto(s)
Bibliometría , Cambio Climático , China , Bases de Datos Factuales , Publicaciones
7.
J Colloid Interface Sci ; 610: 970-981, 2022 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-34887059

RESUMEN

HYPOTHESIS: Polyurethane plastic waste (PUPW), a port-abundant solid waste, is difficult to degrade naturally and poses a severe threat to the environment. Hence, the effective recycling of PUPW remains a challenge. EXPERIMENTS: Herein, a strategy of converting PUPW into stacked oil/water filtration layer grain through a layer-by-layer (LBL) assembly process is investigated. Notably, such PU-based, grain-stacked, and switchable wettability of the oil/water filter layer is first reported. FINDINGS: The grain-stacked filter layers are flexible for separating immiscible oil/water mixtures, water-in-oil emulsions (WOE), and oil-in-water emulsions (OWE) under gravity over 10 cycle-usages. They can withstand strong acid/alkali solutions (pH = 1-14) and salt solutions over 12 h. Besides, 100-times scale-up experiments have indicated that the obtained filter layers exhibit an upper to 98.2 % separation efficiency for 10 L real industrial oil/water emulsion in the 24 h continuous operation. The demulsification mechanism for emulsions is that the electrostatic interaction along with adsorption between emulsion droplets and grains leads to the uneven distribution of surfactants on the interface film of the emulsion droplets, increasing the probability of tiny droplets colliding and coalescing into large droplets to achieve oil/water separation. This work proposes an effective and economical method of abundant plastic waste for industrial-scale oil-water separation rather than just on the laboratory-scale.

8.
ACS Omega ; 6(48): 32395-32407, 2021 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-34901591

RESUMEN

The mechanisms of CO2/CH4 adsorption in coal are the theoretical foundation for CO2 sequestration in coal seams targeted for enhanced coalbed methane recovery. Herein, by changing the model (low rank coal: WMC, middle rank coal: XM and high rank coal: CZ) with plenty of side aliphatic chains and functional groups established in the literature, the influence and mechanism of pore parameters and functional groups(-CH3, -OH, -C2O, -C=O) on the adsorption of CO2 and CH4 in different rank coals are systematically studied. Using the Connolly surface algorithm to calculate the pore volume (V F) and the specific surface area (S SA) of coal with different functional groups, it can be seen that the influence of the functional group change on the pore structure is related to the coal rank. Changing the various functional groups in the original coal structure to a unified functional group (-CH3, -OH, -C2O, or -C=O) will increase the accessible pore volume (V F) and the specific surface area (S SA), except in low-rank and middle-rank coal, where the ordered arrangement of -C=O will decrease V F and S SA. The adsorption capacities of different pore parameters and functional groups were calculated by Grand Canonical Monte Carlo simulation and density functional theory. On pure adsorption, the pore parameters exert greater influence than the functional groups. By comparing the adsorption energy of the original pore structure containing functional groups and that of modified pores without functional groups, the contributions of the pore structure and original functional groups on CO2/CH4 adsorption are 71 and 29% and 83 and 17%, respectively. Small-diameter pores and -C2O have a strong adsorption capacity. In terms of competitive adsorption, the -C=O functional groups and pore diameters ranging from 1.0 to 2.0 nm can significantly enhance the selectivity of CO2 over CH4. The CH4 and CO2 adsorption does not occur via rigorous monolayer adsorption; multilayer adsorption can occur for CH4 and CO2 with pore diameters of 1.0-2.0 and 1.0-2.2 nm, respectively, thus causing micropore filling. These quantitative results establish a foundation for the development of adsorption theory for CO2/CH4 in coal.

9.
Nanomaterials (Basel) ; 11(11)2021 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-34835611

RESUMEN

Efficient dehydrogenation of cycloalkanes under mild conditions is the key to large-scale application of cycloalkanes as a hydrogen storage medium. In this paper, a series of active metals loaded on nitrogen-doped carbon (M/CN, M = Pt, Pd, Ir, Rh, Au, Ru, Ag, Ni, Cu) were prepared to learn the role of active metals in cycloalkane dehydrogenation with cyclohexane as the model reactant. Only Pt/CN, Pd/CN, Rh/CN and Ir/CN can catalyze the dehydrogenation of cyclohexane under the set conditions. Among them, Pt/CN exhibited the best catalytic activity with the TOF value of 269.32 h-1 at 180 °C, followed by Pd/CN, Rh/CN and Ir/CN successively. More importantly, the difference of catalytic activity between these active metals diminishes with the increase in temperature. This implies that there is a thermodynamic effect of cyclohexane dehydrogenation with the synthetic catalysts, which was evidenced by the study on the activation energy. In addition, the effects of molecular structure on cycloalkane dehydrogenation catalyzed by Pt/CN were studied. The results reveal that cycloalkane dehydrogenation activity and hydrogen production rate can be enhanced by optimizing the type, quantity and position of alkyl substituents on cyclohexane.

10.
Nanomaterials (Basel) ; 11(10)2021 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-34685163

RESUMEN

As the two types of major impurities in FCC slurry oil (SLO), olefins and sulfur seriously deteriorate the preparation and quality of mesophase pitch or needle coke. The development of a hydrotreatment for SLO to remove olefins and sulfur selectively becomes imperative. This work presents the potentiality of dispersed Mo2C and MoS2 nanoparticles as selective hydrotreating catalysts of SLO. Mo2C was synthesized by the carbonization of citric acid, ammonium molybdate and KCl mixtures while MoS2 was prepared from the decomposition of precursors. These catalysts were characterized by XRD, HRTEM, XPS, BJH, BET, and applied to the hydrotreating of an SLO surrogate with defined components and real SLO. The conversion of olefins, dibenzothiophene and anthracene in the surrogate was detected by GC-MS. Elemental analysis, bromine number, diene value, 1H-NMR and spot test were used to characterize the changes of the real SLO. The results show that hydrotreating the SLO surrogate with a very small amount of Mo-based nanoparticles could selectively remove olefins and sulfur without the overhydrogenation of polyaromatics. Mo2C exhibited much better activity than MoS2, with 95% of olefins and dibenzothiophene in the surrogate removed while only 15% anthracene was hydrogenated. The stability of the real SLO was significantly improved. Its structural parameters changed subtly, proving the aromatic macromolecules had been preserved.

11.
ACS Omega ; 6(36): 23317-23328, 2021 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-34549132

RESUMEN

The solubility of CO in heavy oils is an important parameter for designing and optimizing the partial upgrading process of heavy oil under CO/syngas and water. To study the structure-solubility relationship of CO dispersion in organic liquids, the solubility of CO in hydrocarbons (n-hexane, n-octane, n-hexadecane, cyclohexane, toluene, and 1-methylnaphthalene), petroleum distillates, and residues from Canadian oil sand bitumen was measured at different temperatures and pressures. The dispersion behavior of CO in different molecules was simulated by the molecular dynamics calculation. The role of water on CO dispersion in these systems was also explored. Experimental data show that the increase of both paraffinic chain length and aromaticity of molecules could hinder the dissolution of CO. By theoretical calculation, it is found that n-hexadecane and 1-methylnaphthalene present the strongest self-aggregation tendency, resulting in the low interaction with CO. The intermolecular forces of hydrocarbons appear to be the key factor determining the CO solubility. The dissolved H2O molecules could weaken the intermolecular forces of hydrocarbons and thus increase the CO solubility. Based on the model system study, the solubility of CO in complex petroleum distillates and heavy residues is rationalized by their molecular composition, which is mainly dependent on the relative proportion of paraffins to aromatics.

12.
Sci Total Environ ; 790: 148110, 2021 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-34380286

RESUMEN

Climate change and human development may lead to a serious crisis in food security in China, especially in areas with both water shortages and large grain production. Thus, the quantitative evaluation of future food security risk considering water scarcity is increasingly important. Here, we combined water scarcity and crop production data under different scenarios of representative concentration pathways (RCPs) and shared socioeconomic pathways (SSPs), incorporating demographic, food habit and water resource factors, to develop a new framework for measuring China's food security risk. The results show that the water scarcity and crop production-water crisis (CPWC) of China would both be aggravated during the 21st century. In particular, northern China might face more serious water scarcity than southern China and has a higher contribution rate to the national crop production-water crisis. Food scarcity in China might occur at some point in the 21st century under all SSP scenarios, except SSP1 (sustainability development pathway). The next 40 years could be the most critical period for ensuring China's food security. Moreover, by comparing the RCP2.6 and RCP6.0 scenarios, we also find that higher food production does not represent lower food security risk. The food security risk of the RCP26 scenario with higher food production was significantly higher than that of the RCP6.0 scenario at the same SSP because higher grain production comes from water shortage areas. From the perspective of societal development scenarios, SSP1 provided better results for both the risk of food security and water security in the 21st century. Our findings therefore provide useful information for a comprehensive understanding of long-term food security and water security of China.


Asunto(s)
Seguridad Alimentaria , Inseguridad Hídrica , China , Cambio Climático , Producción de Cultivos , Humanos , Factores Socioeconómicos
13.
Artículo en Inglés | MEDLINE | ID: mdl-33535711

RESUMEN

The rebound effect exists widely in the fields of energy, irrigation, and other resource utilizations. Previous studies have predicted the evolution of different resource utilizations under the shared socioeconomic pathways (SSPs), but it is still unclear whether total water use has a rebound effect. This study uses the SSPs as the basic prediction framework and evaluates the water resources and economic status of the provinces in China using the hydro-economic (HE) classification method. Then, combined with the SSPs scenario setting parameters, the conditional convergence model and the method recommended by the Food and Agriculture Organization of the United Nations (FAO) are used to simulate the changes in water use efficiency of the different provinces in China under different scenarios. Based on the future GDP forecast data of China's provinces, combined with the forecast of water use efficiency changes, the total water use changes in China's 31 provinces under different pathways from 2016 to 2030 are calculated. Among them, the future GDP data is predicted based on the Cobb-Douglas production function and SSPs scenario settings. Using a comprehensive evaluation of the evolution of the efficiency and the total amount, this study reveals whether there is a rebound effect. The results showed that with the continuous growth in the water use efficiency, the total water use had a "U" type trend, which indicated that there was a rebound effect in the total water use of China under the different SSPs. Based on this information, this study proposes some suggestions for irrigation water-saving technologies and policies.


Asunto(s)
Agricultura , Recursos Hídricos , China , Factores Socioeconómicos , Agua
14.
Proteomics Clin Appl ; 15(1): e2000056, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33098374

RESUMEN

PURPOSE: The prognosis for colorectal cancer (CRC) patients is drastically impacted by the presence of lymph node or liver metastases at diagnosis or resection. On this basis it is sought to identify novel proteins as biomarkers and determinants of CRC metastasis. EXPERIMENTAL DESIGN: Proteomic analyses are undertaken using primary tissues from ten Chinese CRC patients presenting with or without liver metastases and immunohistochemistry used to validate selected proteins in an independent patient cohort. RESULTS: Comparing CRC against paired normal adjacent tissues identifies 1559 differentially expressed proteins (DEPs) with 974 upregulated and 585 downregulated proteins, respectively. The highest number of DEPs is selectively associated with metastatic tumors (519 upregulated and 267 downregulated proteins, respectively) with a smaller number of unique DEPs identified only in non-metastatic CRC cases (116 upregulated and 29 downregulated proteins, respectively). The remaining DEPs are commonly expressed in both non-metastatic and metastatic tumors. The upregulation of three representative DEPs (S100A11, S100P, and RBM25) is confirmed using immunohistochemistry against 154 CRC tissues embedded in a tissue microarray. CONCLUSIONS AND CLINICAL RELEVANCE: The data reveal both previously identified CRC biomarkers along with novel candidates which provide a ready resource of DEPs in CRC for further investigation.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Proteínas de Unión al Calcio/metabolismo , Neoplasias Colorrectales/metabolismo , Proteínas de Neoplasias/metabolismo , Proteómica , Proteínas S100/metabolismo , Adulto , Humanos , Masculino , Persona de Mediana Edad , Pronóstico
15.
Artículo en Inglés | MEDLINE | ID: mdl-33207673

RESUMEN

By integrating multiple remote sensing data sources this study accurately assesses the spatiotemporal characteristics of changes in ecosystem service values (ESVs) in the Yellow River Basin from 2000 to 2015 through Theil-Sen median trend analysis and the Mann-Kendall test. The stability and continuity of the ESVs were comprehensively characterized using coefficients of variation and the Hurst exponent. The degree of coherence between ESVs and economic growth (represented by gross domestic product GDP) on the same temporal and spatial scales was analyzed using ecological-economic coordination (EEC) models. The results show that (1) from 2001 to 2015 the total ESV and the ESV per unit area in the Yellow River Basin generally showed a U-shaped pattern (decreasing slightly then increasing rapidly). (2) The areas with increasing ESVs made up approximately 55.6% of the total area of the river basin. The areas with a decreasing pattern were mainly in the west and north of the Yellow River Basin. (3) The stability and continuity of the ESVs showed a clustered, compact distribution. (4) The most common level of EEC was slightly uncoordinated followed by slightly coordinated and highly coordinated. The proportion of coordinated areas was relatively higher in cultivated land and the lowest in built-up land.


Asunto(s)
Desarrollo Económico , Ecosistema , Ríos , China , Conservación de los Recursos Naturales/economía , Análisis Espacio-Temporal
16.
ACS Sens ; 5(12): 4027-4034, 2020 12 24.
Artículo en Inglés | MEDLINE | ID: mdl-33253549

RESUMEN

Fluorescence microscopic analysis of checkpoint protein expression is capable of predicting clinical outcomes for checkpoint blockade immunotherapy. However, accurate detection of their expression levels is hindered by fluorophore photobleaching and cell autofluorescence. We now develop a sensitive and robust fluorescence microscopy method that uses antifade graphite-structured carbon dots (GCDs) on a plasmonic Ag substrate (named ACPAS) for the accurate detection of checkpoint proteins in immunotherapy. In ACPAS, a Ag substrate is used to enhance the fluorescence of GCDs while a continuous illumination is implemented to quench cell autofluorescence, thus enabling a dramatic improvement in the signal-to-background ratio by up to 33-fold. We use ACPAS to monitor programmed death ligand-1 (PD-L1) expression levels on various tumor cells and finely differentiate their microscopic changes in combination with chemokine receptor CXCR4-targeted treatments. ACPAS analysis reveals for the first time that CXCR4 agonist (SDF-1α) and antagonist (AMD3100) can potentiate PD-L1 expression by down-regulating CXCR4 expression on tumor cells, which provides valuable information on the development of anti-PD-L1 and anti-CXCR4 combination therapy. We envision that ACPAS will become a broadly useful tool for protein expression studies in biomedicine and life sciences.


Asunto(s)
Carbono , Receptor de Muerte Celular Programada 1 , Inmunoterapia
17.
Oncol Lett ; 17(2): 1646-1654, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30675224

RESUMEN

MicroRNAs serve crucial functions in cancer progression by inhibiting the translation of target genes and causing mRNA degradation. However, the underlying regulatory mechanism of Let-7b in osteosarcoma (OS) has not, to the best of our knowledge, been comprehensively elucidated. The aim of the present study was to investigate the function of Let-7b in OS and clarify the regulation of insulin-like growth factor 1 receptor (IGF1R) by Let-7b. It was observed that Let-7b was significantly downregulated in OS tissues and cell lines compared with the matched adjacent non-tumorous tissues and human normal osteoblastic cell line hFOB 1.19. Overexpression of Let-7b significantly inhibited the proliferation and invasion of U2OS and SAOS-2 cells. A luciferase reporter assay validated that IGF1R was a downstream and functional target of Let-7b. Let-7b was also able to decrease the expression levels of IGF1R protein. Functional studies revealed that the antitumor effect of Let-7b was probably due to targeting and suppressing IGF1R expression. Furthermore, in OS tissues, IGF1R was identified to be significantly upregulated and negatively correlated with Let-7b levels. In conclusion, the results of the present study indicated that Let-7b suppresses OS cellular proliferation and invasion via targeting IGF1R. A novel candidate prognostic factor was identified and it is suggested that the Let-7b/IGF1R axis may represent a novel anti-metastasis therapeutic target in OS.

18.
Bioconjug Chem ; 29(11): 3658-3666, 2018 11 21.
Artículo en Inglés | MEDLINE | ID: mdl-30346721

RESUMEN

Nanotechnology-enhanced drug delivery via receptor-mediated endocytosis provides a promising and clinically translatable strategy to targeted diagnosis and precise therapy, yet an in-depth understanding of this process is technically limited by our inability to probe the nanocarrier distributions at the cell surface and inside the cell at nanoscale resolution. Here, we report small blinking single-layer graphene oxide nanosheet (GONS) that  serves both as a nanoscopy fluorophore and as a drug-bearing nanocarrier for addressing such a task. The GONS blinks spontaneously with a low duty cycle (∼0.003), high photon output (∼3000 photons per switching event), and higher photostability than organic dyes, thus affording well for single molecule localization-based super-resolution imaging. Applying the localization analysis, we reveal GONS clustering size, GONS number in each cluster, and the number fraction of GONSs that participate in clustering at the cell surface and in the cytoplasm, respectively, and track their evolutions over 24 h. The data suggest that the nanocarrier clustering and distribution at the cell surface control their endocytosis and accumulation inside the cell. This process is drug-independent during which drug transportation into the destination relies on its own loading and escaping capability. Thus, this work demonstrates the great potential of the dual-functional GONS in quantitative super-resolution imaging of drug carriers in cells, which is helpful for the rational design of a smart drug delivery system aiming at achieving full therapeutic capacity.


Asunto(s)
Portadores de Fármacos , Grafito/administración & dosificación , Nanopartículas , Línea Celular Tumoral , Endocitosis , Colorantes Fluorescentes/química , Células HeLa , Humanos
19.
Cell Physiol Biochem ; 50(2): 437-451, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30308519

RESUMEN

BACKGROUND/AIMS: The roles and related mechanisms of RNA binding protein FUS (fused in sarcoma/translocated in liposarcoma) are unclear in numerous cancers, including hepatocellular carcinoma (HCC). METHODS: Quantitative reverse transcription PCR (qRT-PCR), western blot, cell viability, transwell migration and invasion, tumor spheres formation and in vivo tumor formation assays were used to examine the effects of FUS on HCC progression in HuH7 and MHCC97 cells. Additionally, transcriptome analysis based on RNA-sequencing data, qRT-PCR, western blots, luciferase reporter and RNA binding protein immunoprecipitation (RIP) assays were used to explore the LATS1/2 (large tumor suppressor kinases 1/2)-related mechanisms contributing to FUS functions. Finally, qRT-PCR and western blot analysis were used to detect the levels of FUS and LATS1/2 in HCC and adjacent normal tissues, and the correlation between them in HCC tissues. RESULTS: Overexpression of FUS decreased cell viability, migration, invasion and stemness. Moreover, FUS interacted and stabilized LATS1/2 stability, and thus promoted LATS1/2 expression and activated Hippo pathway. Finally, FUS and LAST1/2 levels were positively correlated and significantly down-regulated in HCC tissues. CONCLUSION: We demonstrate that FUS/LATS1/2 axis inhibits HCC progression via activating Hippo pathway.


Asunto(s)
Carcinoma Hepatocelular/patología , Neoplasias Hepáticas/patología , Proteínas Serina-Treonina Quinasas/metabolismo , Proteína FUS de Unión a ARN/metabolismo , Proteínas Supresoras de Tumor/metabolismo , Carcinoma Hepatocelular/metabolismo , Línea Celular Tumoral , Movimiento Celular , Proliferación Celular , Progresión de la Enfermedad , Transición Epitelial-Mesenquimal , Femenino , Vía de Señalización Hippo , Humanos , Neoplasias Hepáticas/metabolismo , Masculino , Persona de Mediana Edad , Proteínas Serina-Treonina Quinasas/antagonistas & inhibidores , Proteínas Serina-Treonina Quinasas/genética , Interferencia de ARN , Estabilidad del ARN , ARN Mensajero/metabolismo , ARN Interferente Pequeño/metabolismo , Proteína FUS de Unión a ARN/genética , Transducción de Señal , Proteínas Supresoras de Tumor/antagonistas & inhibidores , Proteínas Supresoras de Tumor/genética
20.
Zhonghua Wai Ke Za Zhi ; 53(1): 72-6, 2015 Jan.
Artículo en Chino | MEDLINE | ID: mdl-25876624

RESUMEN

Regenerative surgery is an emerging multidisciplinary field that has the potential to transform the surgical treatment for diseases and injuries. This article provides a brief overview of the history of surgery and regenerative medicine, introduces the new concept of regenerative surgery, describes the surgical procedures, and discusses the role of surgeons in developing and implementing these technologies. Insights gained from recent clinical research of regenerative medicine are beginning to yield three strategies for regenerative therapies for surgical diseases, and this review also provides the challenges and translational perspectives of these different strategies.


Asunto(s)
Cirugía General/tendencias , Medicina Regenerativa , Investigación Biomédica , Humanos
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