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1.
Sci Total Environ ; 901: 165748, 2023 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-37495122

RESUMO

The study of oxidation characteristics of carbon black particle is the basis to investigate the regeneration process and characteristics of diesel particulate filter (DPF). Based on the fixed-bed test bench, the gas and particle emission characteristics of carbon black oxidation process in the presence of water are investigated under different temperatures, Printex-U (PU) masses, and catalysts. The experimental results show that the rise of temperature and PU mass increases the emissions of CO, CO2 and the total average particle number (PN). The oxidation efficiency (η) increases with temperature, but decreases with PU mass. The addition of catalysts promotes PU oxidation, and reduces CO emission. Due to the influence of particle diffusion, CeO2 has slightly lower efficiency than Pt/Al2O3 in the same ratio (1:1), but it is beneficial to significantly reduce particle emission, especially as the ratio increases (1:5). Water decreases CO and the η in PU oxidation, and the negative impact is gradually reduced after 3 % water concentration; However, the PN significantly increases, and expands the particle size range, particularly at high temperature and adding Pt/Al2O3 (from about 10 nm to 6- 30 nm, and a large number of particles with 30- 100 nm are produced). Additionally, the CO2/CO ratio of carbon black oxidation gradually increases with water concentration. Controlling DPF regeneration needs to strike a balance between the benefits on increasing oxidation efficiency and the potential negatives on particulate and harmful gas emission.

2.
Artigo em Inglês | MEDLINE | ID: mdl-36900903

RESUMO

Green innovation is an important strategy in seeking sustainable competitive advantages. This paper investigates the impact of enterprise digitization on green innovation and its mechanisms. We find that enterprise digital transformation has a significant effect on the promotion of green innovation. This positive effect mainly stems from the advantage of resource reallocation generated by enterprise digitalization that can alleviate financing constraints and raise risk-taking levels. Furthermore, the level of economic development strengthens the impact of enterprise digitization on green innovation, and the positive relationship between enterprise digitization and green innovation is stronger in regions with stronger environmental regulation and higher intellectual property protection, as well as in state-owned and heavily polluting enterprises. Digitization can optimize resource utilization, strengthen the capacity of green innovation in pollution reduction and promote the clean production of enterprises. Our results show that enterprise digitization plays a positive role in innovation activities. Furthermore, our results show that enterprise digitization plays a positive role in innovation activities.


Assuntos
Desenvolvimento Econômico , Poluição Ambiental , China
3.
Plant Foods Hum Nutr ; 71(2): 123-8, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27165128

RESUMO

Corn bran is a byproduct produced from corn milling; it is rich in ferulic acid and hemicellulose. In this research, the effects of feruloylated oligosaccharides (FOs) from maize bran on the microbial diversity and profiles in rat feces were investigated through 16S rRNA sequencing. FOs significantly increased bacterial richness and diversity compared with the control and xylooligosaccharides (XOS) alone. In comparison with the control group and the group administrated with XOS, FOs orally administered at 300 mg/kg increased OTU in feces by 57.0 and 24.8 %, and Chao value by 93.4 and 37.6 %, respectively. FOs also influenced obesity- and diabetes-associated bacteria. Oral administration of FOs at 300 mg/kg decreased the ratio of Firmicutes to Bacteroidetes from 477.7:1 to 55.1:1; greatly increased the reads of bacteria that were previously found resistant against diabetes in rats, such as Actinobacteria, Bacteroides, and Lactobacillus; whereas decreased diabetes-prone bacteria, such as Clostridium and Firmicutes.


Assuntos
Bactérias/efeitos dos fármacos , Fibras na Dieta/administração & dosagem , Microbioma Gastrointestinal/efeitos dos fármacos , Oligossacarídeos/administração & dosagem , Zea mays/química , Administração Oral , Animais , Bactérias/genética , Bacteroidetes/efeitos dos fármacos , Bacteroidetes/genética , Ácidos Cumáricos/metabolismo , Fezes/microbiologia , Firmicutes/efeitos dos fármacos , Firmicutes/genética , Microbioma Gastrointestinal/genética , Glucuronatos/administração & dosagem , Lignina/química , Masculino , Oligossacarídeos/metabolismo , Polissacarídeos/metabolismo , RNA Ribossômico 16S/genética , Ratos
4.
Cancer Lett ; 358(2): 200-209, 2015 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-25543087

RESUMO

Lymphangiogenesis critically contributes to the lymphatic metastasis of colorectal carcinomas (CRCs), but the underlying mechanism of CRC lymphangiogenesis remains largely elusive. We have previously demonstrated that Semaphorin-3F (SEMA3F) is critically involved in CRC metastasis, and the receptor of SEMA3F, neuropilin-2 (NRP2), originally described as an axon guiding chemorepulsant implicated in nerve development, has been suggested in promoting lymphangiogenesis via acting as an obligate co-receptor of VEGFR3 cooperatively enhancing the activity of VEGF-C. Our present study revealed that in colorectal carcinomas, NRP2 expression levels of tumor-associated lymphatic endothelial cells (LECs) are significantly correlated with the density of tumor lymphatic vessels. In vitro, activation of NRP2 in LECs substantially facilitates their migration, sprouting, and tubulogenesis capacity via regulating the rearrangement of cytoskeleton polarity. In vivo model further showed that in the xenografts generated from SEMA3F knockdown CRC cells, NRP2 is substantially activated in tumor-associated LECs, resulting in a significantly increased tumor lymphangiogenesis. Further evidence demonstrated that CRC cell induces the activation of NRP2 in LECs to promote tumor lymphangiogenesis via integrinα9ß1/FAK/Erk pathway independent VEGF-C/VEGFR3 signaling. Our study for the first time revealed the novel molecular mechanism of NRP2-mediated-lymphangiogenesis in CRCs, suggesting NRP2 as a potential therapeutic target in preventing lymphatic metastasis of CRCs.


Assuntos
Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Linfangiogênese , Neuropilina-2/metabolismo , Transdução de Sinais , Fator C de Crescimento do Endotélio Vascular/metabolismo , Receptor 3 de Fatores de Crescimento do Endotélio Vascular/metabolismo , Animais , Linhagem Celular Tumoral , Movimento Celular/genética , Neoplasias Colorretais/genética , Modelos Animais de Doenças , Quinase 1 de Adesão Focal/metabolismo , Humanos , Integrina beta1/metabolismo , Integrinas/metabolismo , Linfangiogênese/genética , Camundongos , Neuropilina-2/genética , Proteínas rac1 de Ligação ao GTP/metabolismo
5.
Clin Cancer Res ; 17(9): 2702-11, 2011 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-21349996

RESUMO

PURPOSE: To elucidate the role of Semaphorin-3F (SEMA3F), originally described as an axon guiding chemorepulsant implicated in nerve development, in the progression of colorectal carcinoma. EXPERIMENTAL DESIGN: SEMA3F and its receptor NRP2 were examined in 72 cases of human colorectal carcinoma specimens and cell lines LoVo, SW480, and SW620 with immunohistochemistry and Western blotting. SEMA3F mRNA expression in the frozen tissue specimens and cell lines was examined with quantitative reverse transcriptase-PCR. Confocal laser scanning microscopy was used for detection of cellular localization of the proteins by immunofluorescent staining. MTT assay, flow cytometry, cell adhesion and migration, and xenografts were used to evaluate biological significance of SEMA3F. RESULTS: SEMA3F was significantly reduced in colorectal carcinoma tissues and cell lines. Overexpression of SEMA3F resulted in reduced proliferation, adhesion to fibronectin, and migratory capability as well as reduced S-phase population and integrin αvß3 expression of SW480 colon cancer cells. In addition, SEMA3F-overexpressing cells exhibited diminished tumorigenesis when transplanted orthotopically in nude mice and reduced liver metastases. Moreover, transfection of siRNA targeting SEMA3F in colon cancer cells increased their tumorigenicity in vivo. CONCLUSIONS: Endogenous SEMA3F acts as a suppressor of the growth and metastasis of human colorectal cancer cells.


Assuntos
Carcinoma/patologia , Proliferação de Células , Neoplasias Colorretais/patologia , Proteínas de Membrana/fisiologia , Proteínas do Tecido Nervoso/fisiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Axônios/metabolismo , Axônios/fisiologia , Carcinoma/genética , Carcinoma/metabolismo , Carcinoma/prevenção & controle , Linhagem Celular Tumoral , Inibição de Migração Celular/genética , Proliferação de Células/efeitos dos fármacos , Fatores Quimiotáticos/antagonistas & inibidores , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/prevenção & controle , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Terapia Genética , Humanos , Masculino , Proteínas de Membrana/antagonistas & inibidores , Proteínas de Membrana/genética , Camundongos , Camundongos Nus , Pessoa de Meia-Idade , Metástase Neoplásica , Proteínas do Tecido Nervoso/antagonistas & inibidores , Proteínas do Tecido Nervoso/genética , RNA Interferente Pequeno/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto
6.
Cancer Biol Ther ; 9(3): 186-91, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20023414

RESUMO

The objective of this study was to investigate whether tumor derived fibronectin alternatively spliced EDA domain has a lymphangiogenic potency on human lymphatic endothelial cells (LECs) in tumor generation to facilitate tumor lymphatic metastasis. LECs were cultured in three-dimentional culture system and treated with SW480 supernant which was highly rich in EDA, the result demonstrated that SW480 supernant could facilitate tube-like formations of LECs evidently when compared with controls. Integrinalpha9 was identified by immunofluorescence to be a specific receptor for EDA because we found co-locozation of EDA and integrinalpha9 on LECs as well as significant upregulation of integrinalpha9 in SW480 supernant treated group. Western blot and immunofluorescence revealed that EDA also had important roles accommodating the expressions of some key regulators of lymphangiogenesis such as Prox1 and F-actin so as to facilitate motility and sprouting of LECs. In addition, it had been confirmed that all of these effects could be inhibited markedly by EDA antibody (IST-9). Based on these findings, we assert that EDA derived from tumor cells has an important role in facilitating lymphangiogenesis of malignant tumor. Furthermore, EDA pathway may provide a potent target for tumor lymphatic metastasis therapy.


Assuntos
Processamento Alternativo , Neoplasias Colorretais/genética , Células Endoteliais/patologia , Fibronectinas/genética , Linfangiogênese , Actinas/metabolismo , Anticorpos Monoclonais/farmacologia , Western Blotting , Movimento Celular , Proliferação de Células , Células Cultivadas , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Citoesqueleto/metabolismo , Células Endoteliais/metabolismo , Fibronectinas/metabolismo , Imunofluorescência , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Humanos , Integrinas/genética , Integrinas/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Proteínas Supressoras de Tumor/genética , Proteínas Supressoras de Tumor/metabolismo , Regulação para Cima
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