Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 11 de 11
Filtrar
1.
Genet Res (Camb) ; 2023: 8586507, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37113556

RESUMO

Background: Cysteine and Glycine Rich Protein 1 (CSRP1) belongs to the cysteine-rich protein family, which contains a unique double-zinc finger motif and is important for development and cellular differentiation. Abnormal expression of CSRP1 was reported within several malignancies such as prostate cancer and acute myeloid leukemia. Here, we explored function of CSRP1 within colon adenocarcinoma (COAD) for the first time. Methods: The mRNA levels of CSRP1 in COADs were obtained from TCGA datasets. CSRP1 protein expressions in COADs were tested via immunohistochemistry staining. Patients' prognosis was evaluated using both univariate analysis and multivariate analysis. Two human COAD originated cancer cell lines, Caco-2, and HT-29, were used for cellular experiments including shRNA knockdown, proliferation assay, and migration assay. In vivo model was established using nude mice xenografts to further validate the role of CSRP1 in COAD progression. Results: The mRNA levels of CSRP1 are elevated in COAD specimens from patients with more advanced tumor stages and higher Carcinoembryonic Antigen (CEA) levels. In addition, higher CSRP1 mRNA level indicates worse COAD prognosis. Consistently, higher CSRP1 protein expression is correlated with worse overall survival according to both univariate and multivariate analysis, indicating that CSRP1 is a new COAD prognostic factor. Furthermore, COAD cells transfected with CSRP1-shRNAs exhibit attenuated proliferation and migration capacities. Finally, growth of xenografts originated from CSRP1-knockdown cells is inhibited comparing to the control ones. Conclusions: Expression of CSRP1 is positively correlated with COAD progression, which can promote tumor growth and migration. Higher CSRP1 can is a novel independent prognostic factor of COAD.


Assuntos
Adenocarcinoma , Neoplasias do Colo , Animais , Humanos , Masculino , Camundongos , Adenocarcinoma/genética , Adenocarcinoma/metabolismo , Adenocarcinoma/patologia , Biomarcadores , Células CACO-2 , Neoplasias do Colo/genética , Neoplasias do Colo/metabolismo , Neoplasias do Colo/patologia , Cisteína , Camundongos Nus , Prognóstico , RNA Mensageiro/genética
2.
J Clin Lab Anal ; 36(7): e24520, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35666636

RESUMO

BACKGROUND: The aim of this study was to explore the function and mechanism of GKN1 in gastric cancer (GC) progression. METHODS: Firstly, we used GEO2R to perform differential gene analysis on GSE26942 and GSE79973 and constructed the protein-protein interaction network of differential genes by STRING. Next, the cytoHubba, Mcode plugins, and GEPIA were used to obtain our follow-up research object GKN1. Then, the function of GKN1 in GC was verified by scratch and transwell assay in GC cells. We further analyzed the genes related to GKN1 through LinkedOmics, and exported top 100 genes positively or negatively correlated with GKN1. Meanwhile, Metascape was performed on these genes. Finally, we analyzed the miRNAs that bind to GKN1 through the miRDB and verified the correlation between miR-548d-3p and GKN1 using dual-fluorescence and quantitative PCR experiments. RESULTS: Bioinformatics analysis showed that there were 52 differential genes on GSE26942 and GSE79973. In addition, the results of functional assays indicated that overexpressed GKN1 can inhibit GC cell migration and invasion, while GKN1 knockdown demonstrated the opposite effect. Additionally, Metascape analysis results showed that the 3'-UTR region of mRNA is rich in AU sequences, based on which we infer that mRNA may be regulated by miRNA. Dual-fluorescence and quantitative PCR assays clarified that miR-548d-3p may be one of the target miRNAs of GKN1, which was up-regulated in GC tissues. CONCLUSIONS: In summary, we clarified that miR-548d-3p regulates GKN1 to participate in GC cell migration and invasion, and provides a possible target for the prognostic diagnosis and treatment of GC.


Assuntos
MicroRNAs , Hormônios Peptídicos , Neoplasias Gástricas , Regiões 3' não Traduzidas , Movimento Celular/genética , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica , Humanos , MicroRNAs/genética , Hormônios Peptídicos/genética , RNA Mensageiro/genética , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismo
3.
Polymers (Basel) ; 16(4)2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38399883

RESUMO

The development of precious metal-free (M-N-C) catalysts for the oxygen reduction reaction (ORR) is considered crucial for reducing fuel cell costs. Herein, Co-Zn/NC interconnected frameworks with uniformly dispersed Co nanoparticles and graphitic carbon are designed and successfully synthesized through the in situ growth of zeolitic imidazolate frameworks (ZIF67 and ZIF8) along with biomass nano-microfibrillar cellulose (MFC), followed by pyrolysis. A Co-Zn/NC composite is prepared by combining Co-Zn/NC with a perfluorosulfonic acid polymer. The Co-Zn/NC composite catalyst exhibits excellent ORR catalytic activity (E0 = 0.974 V vs. RHE, E1/2 = 0.858 V vs. RHE) and good long-term durability, with 90% current retention after 10000s, surpassing that of commercial Pt/C in alkaline media. The hierarchical porous structure, coupled with the uniform distribution of Co nanoparticles and nitrogen doping, contributes to superior electrocatalytic performance, while the interconnected frameworks and graphitic carbon ensure good stability. Additionally, the Co-Zn/NC composite demonstrates promising applications in acidic media. This strategy offers significant guidance to develop advanced non-precious metal carbon-based catalysts for highly efficient and stable ORR.

4.
Polymers (Basel) ; 16(3)2024 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-38337244

RESUMO

Monodisperse mesoporous carbon spheres (MCS) were synthesized and their potential applications in ethylene propylene diene monomer (EPDM) foam were evaluated. The obtained MCS exhibited a high specific surface area ranging from 621-to 735 m2/g along with large pore sizes. It was observed that the incorporation of MCS into EPDM foam rubber significantly enhances its mechanical properties. The prepared MCS-40 rubber composites exhibit the highest tear strength of 210 N/m and tensile strength of 132.72 kPa, surpassing those of other samples. The enhancement mechanism was further investigated by employing computer simulation technology. The pores within the MCS allowed for the infiltration of EPDM molecular chains, thereby strengthening the interaction forces between the filler and matrix. Moreover, a higher specific surface area resulted in greater adsorption of molecular chains onto the surface of these carbon spheres. This research offers novel insights for understanding the enhancement mechanism of monodisperse mesoporous particles/polymer composites (MCS/EPDM) and highlights their potential application in high-performance rubber composites.

5.
Adv Sci (Weinh) ; 10(30): e2303969, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37653601

RESUMO

Hydrogen energy as the next-generation clean energy carrier has attracted the attention of both academic and industrial fields. A key limit in the current stage is the operation temperature of hydrogen fuel cells, which lies in the slow development of high-temperature and high-efficiency proton exchange membranes. Currently, much research effort has been devoted to this field, and very innovative material systems have been developed. The authors think it is the right time to make a short summary of the high-temperature proton exchange membranes (HT-PEMs), the fundamentals, and developments, which can help the researchers to clearly and efficiently gain the key information. In this paper, the development of key materials and optimization strategies, the degradation mechanism and possible solutions, and the most common morphology characterization techniques as well as correlations between morphology and overall properties have been systematically summarized.

6.
ACS Omega ; 6(16): 11059-11067, 2021 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-34056259

RESUMO

The stability and activity of the catalysts are crucial for the oxygen reduction reaction (ORR) in fuel cells. Herein, CoFe/N, S-codoped biomass carbon (FB-CoFe-700) with graphitic nanoribbons and multiple CoFe nanoparticles was prepared through a facile thermal pyrolysis followed by an acid treatment process. The evolution of the growth of metal nanoparticles with the formation of graphite during the carbonization process was investigated. Inseparable from graphitic carbon-encased metal nanoparticles with the coexistence of graphitized nanoribbons and graphene-like sheets, FB-CoFe-700 exhibited a remarkable long-term electrocatalytic stability with 90.7% current retention after 50 000 s much superior to that of the commercially available Pt/C (20 wt %) in an alkaline medium. Meanwhile, FB-CoFe-700 displayed promising ORR catalytic activity (E 0 = 0.92 V vs reversible hydrogen electrode (RHE), E 1/2 = 0.82 V vs RHE, and n = 3.97) very similar to that of commercial Pt/C and outstanding methanol tolerance in an alkaline medium. This work is helpful for further development of nonprecious metal-doped carbon electrocatalysts with long-term stability.

7.
Sci Total Environ ; 749: 141578, 2020 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-33370904

RESUMO

Investigating the drivers of phenotypic and genetic divergence can reveal the underlying processes and strategies that species adopt in rapidly changing environments. However, knowledge of adaptive strategies and the underlying mechanisms is lacking for the majority of taxa, especially those living in habitats sensitive to climate change. Here, we investigated 20 populations of a Tertiary-relict tree species, Euptelea pleiospermum (Eupteleaceae), scattered in a mountain riparian habitat in China. We integrated genetic, growth, and reproductive traits, and evaluated the relative contributions of climatic and soil factors on genetic and functional trait divergence. The E. pleiospermum populations were divided into south and north genetic clusters, and there were significant differences in leaf density and seed mass of adult trees between the two. The spatial pattern of genetic divergence resulted from effects of both isolation by distance (IBD) and isolation by environment (IBE), whereas the divergence of growth and reproductive traits resulted solely from IBE effects. Spatial distance and selection by temperature and soils played dominant roles in genetic divergence. Precipitation drove the spatial divergence of sprouting. Both divergence of leaf density and seed mass were prominently induced by genetic divergence, and the influences might be enhanced by temperature and soil nutrients. We infer that E. pleiospermum populations adopt a resource-conservative strategy with low growth rates and higher sprouting under flooding disturbance, with larger seeds for improved seedling recruitment at lower latitudes. In contrast, high growth rate and sexual reproduction with small seeds are strategies adopted by populations at higher latitudes. We conclude that sprouting reflects a plastic response to precipitation, and leaf density and seed mass reflect local adaption under selection by temperature and soil factors. The underlying mechanisms of species adaptation strategies were trait-specific. Temperature and soil conditions are likely the main ecological factors shaping plant divergence in montane riparian regions.


Assuntos
Ecossistema , Árvores , China , Fenótipo , Plântula
8.
ACS Appl Mater Interfaces ; 12(37): 41580-41589, 2020 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-32815712

RESUMO

Development of nonprecious metal catalysts for oxygen reduction reaction (ORR) to reduce or eliminate Pt-based electrocatalysts is of great importance for fuel cells. Herein, Co/N-codoped carbon with carbon nanofiber (CNF) interconnected three-dimensional (3D) frameworks and graphitic carbon-encapsulated Co nanoparticles were designed and successfully prepared via the in situ growth of zeolitic imidazolate framework-67 (ZIF67) with biomass nano-microfibrillar cellulose (MFC) and then pyrolysis. The catalyst (Co/N-C@CNFs) exhibited outstanding long-term catalytic durability with 92.7% current retention after 70 000 s, which was much higher than that of commercial Pt/C in alkaline media. The support and connection of CNFs to Co/N-C frameworks and the protection of Co nanoparticles by graphite layers contribute to their impressive long-term catalytic stability. Meanwhile, Co/C-N@CNFs displayed excellent ORR catalytic performance (E0 = 0.952 V vs RHE, E1/2 = 0.852 V vs RHE, and n: 4.2) in alkaline media. This strategy provides new insights into developing advanced nonprecious metal carbon-based catalysts for ORR.

9.
Sci Rep ; 6: 18927, 2016 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-26739853

RESUMO

Recently, the defect-induced static magnetic behaviours of nanomaterials have been a cutting-edge issue in diluted magnetic semiconductor materials. However, the dynamic magnetic properties of nanomaterials are commonly ignored if their bulk counterparts are non-magnetic. In the present research, titanium nitride-carbon (TiN/C) nanocomposites were found to exhibit both static and dynamic magnetic properties that vary in the opposite trend. Moreover, novel unconventional electromagnetic resonance behaviour was demonstrated in TiN/C systems, and their permeability and permittivity show similar trend. This is challenging for the traditional understanding of electromagnetism and makes it possible to achieve an appropriate balance between the permeability and permittivity simultaneously in a simple system. Hopefully, the results could provide some valuable clues to revealing the magnetism and electromagnetism of nanostructures.

10.
PLoS One ; 9(5): e97300, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24824996

RESUMO

The stochastic dilution hypothesis has been proposed to explain species coexistence in species-rich communities. The relative importance of the stochastic dilution effects with respect to other effects such as competition and habitat filtering required to be tested. In this study, using data from a 25-ha species-rich subtropical forest plot with a strong topographic structure at Badagongshan in central China, we analyzed overall species associations and fine-scale species interactions between 2,550 species pairs. The result showed that: (1) the proportion of segregation in overall species association analysis at 2 m neighborhood in this plot followed the prediction of the stochastic dilution hypothesis that segregations should decrease with species richness but that at 10 m neighborhood was higher than the prediction. (2) The proportion of no association type was lower than the expectation of stochastic dilution hypothesis. (3) Fine-scale species interaction analyses using Heterogeneous Poisson processes as null models revealed a high proportion (47%) of significant species effects. However, the assumption of separation of scale of this method was not fully met in this plot with a strong fine-scale topographic structure. We also found that for species within the same families, fine-scale positive species interactions occurred more frequently and negative ones occurred less frequently than expected by chance. These results suggested effects of environmental filtering other than species interaction in this forest. (4) We also found that arbor species showed a much higher proportion of significant fine-scale species interactions (66%) than shrub species (18%). We concluded that the stochastic dilution hypothesis only be partly supported and environmental filtering left discernible spatial signals in the spatial associations between species in this species-rich subtropical forest with a strong topographic structure.


Assuntos
Distribuição Animal , Biodiversidade , Biota , Florestas , Modelos Biológicos , China , Especificidade da Espécie , Processos Estocásticos
11.
PLoS One ; 8(6): e66928, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23825588

RESUMO

We used landscape genetics and statistical models to test how landscape features influence connectivity or create barriers to dispersal for a mountain riparian tree species, Euptelea pleiospermum. Young leaves from 1078 individuals belonging to 36 populations at elevations of 900-2000 m along upper reaches of four rivers were genotyped using eight nuclear microsatellite markers. We found no evidence for the unidirectional dispersal hypothesis in E. pleiospermum within each river. The linear dispersal pattern along each river valley is mostly consistent with the "classical metapopulaton" model. Mountain ridges separating rivers were genetic barriers for this wind-pollinated tree species with anemochorous seeds, whereas river valleys provided important corridors for dispersal. Gene flow among populations along elevational gradients within each river prevails over gene flow among populations at similar elevations but from different rivers. This pattern of gene flow is likely to promote elevational range shifts of plant populations and to hinder local adaptation along elevational gradients. This study provides a paradigm to determine which of the two strategies (migration or adaptation) will be adopted by mountain riparian plants under climate warming.


Assuntos
Altitude , Rios , Traqueófitas/genética , Árvores/genética , Desequilíbrio de Ligação , Repetições de Microssatélites/genética , Modelos Genéticos , Polimorfismo Genético
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA