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1.
J Environ Sci (China) ; 146: 163-175, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38969445

RESUMO

Heterogeneous iron-based catalysts have drawn increasing attention in the advanced oxidation of persulfates due to their abundance in nature, the lack of secondary pollution to the environment, and their low cost over the last a few years. In this paper, the latest progress in the research on the activation of persulfate by heterogeneous iron-based catalysts is reviewed from two aspects, in terms of synthesized catalysts (Fe0, Fe2O3, Fe3O4, FeOOH) and natural iron ore catalysts (pyrite, magnetite, hematite, siderite, goethite, ferrohydrite, ilmenite and lepidocrocite) focusing on efforts made to improve the performance of catalysts. The advantages and disadvantages of the synthesized catalysts and natural iron ore were summarized. Particular interests were paid to the activation mechanisms in the catalyst/PS/pollutant system for removal of organic pollutants. Future research challenges in the context of field application were also discussed.


Assuntos
Ferro , Sulfatos , Poluentes Químicos da Água , Catálise , Ferro/química , Sulfatos/química , Poluentes Químicos da Água/química , Oxirredução , Eliminação de Resíduos Líquidos/métodos
2.
Cell Reprogram ; 25(2): 53-64, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-37053510

RESUMO

Exosomes are one kind of small-cell extracellular membranous vesicles that can regulate intercellular communication and give rise to mediating the biological behaviors of cells, involving in tissue formation, repair, the modulation of inflammation, and nerve regeneration. The abundant kinds of cells can secret exosomes, among them, mesenchymal stem cells (MSCs) are very perfect cells for mass production of exosomes. Dental tissue-derived mesenchymal stem cells (DT-MSCs), including dental pulp stem cells, stem cells from exfoliated deciduous teeth, stem cells from apical papilla, stem cells from human periodontal ligament (PDLSCs), gingiva-derived mesenchymal stem cells, dental follicle stem cells, tooth germ stem cells, and alveolar bone-derived mesenchymal stem cells, are now known as a potent tool in the area of cell regeneration and therapy, more importantly, DT-MSCs can also release numerous types of exosomes, participating in the biological functions of cells. Hence, we briefly depict the characteristics of exosomes, give a detailed description of the biological functions and clinical application in some respects of exosomes from DT-MSCs through systematically reviewing the latest evidence, and provide a rationale for their use as tools for potential application in tissue engineering.


Assuntos
Exossomos , Células-Tronco Mesenquimais , Humanos , Ligamento Periodontal , Gengiva , Células-Tronco , Diferenciação Celular/fisiologia
3.
Appl Spectrosc ; 74(11): 1365-1373, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32748642

RESUMO

Many foodstuffs are extremely susceptible to contamination with aflatoxins, in which aflatoxin B1 is highly toxic and carcinogenic. Therefore, it is crucial to develop a rapid and effective analytical method for detecting and monitoring aflatoxin B1 in food. Herein, a surface-enhanced Raman spectroscopic (SERS) method combined with QuEChERS (quick, easy, cheap-effective, rugged, safe) sample pretreatment technique was used to detect aflatoxin B1. Sample preparation was optimized into a one-step extraction method using an Au nanoparticle-based solution (Au sol) as the SERS detection substrate. An affordable portable Raman spectrometer was then used for rapid, label-free, quantitative detection of aflatoxin B1 levels in foodstuffs. This method showed a good linear log relationship between the Raman signal intensity of aflatoxin B1 in the 1-1000 µg L-1 concentration range with a limit of detection of 0.85 µg kg-1 and a correlation coefficient of 0.9836. Rapid aflatoxin B1 detection times of ∼10 min for wheat, corn, and protein feed powder samples were also achieved. This method has high sensitivity, strong specificity, excellent stability, is simple to use, economical, and is suitable for on-site detection, with good prospects for practical application in the field of food safety.


Assuntos
Aflatoxina B1/análise , Contaminação de Alimentos/análise , Inocuidade dos Alimentos/métodos , Triticum/química , Zea mays/química , Ouro/química , Limite de Detecção , Nanopartículas Metálicas/química , Análise Espectral Raman
4.
Bioresour Technol ; 315: 123831, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32707502

RESUMO

Catalytic pyrolysis of rain tree biomass (RTB), a typical horticultural waste, was investigated with nano-NiO as catalyst produced from hazardous nickel plating slag (NPS). It appeared from the analyses by FTIR, TGA, XRD, BET, and FESEM/EDX that nano-NiO produced had a SBET and mean particle size of 53.4 m2/g and 112.3 nm. The catalytic pyrolysis kinetics of RTB with and without catalyst were studied by Friedman method. It was found that the activation energy (Ea) was in the range of 177 to 360 kJ/mol at a conversion rate of 0.1 - 0.75. The results further revealed that the H2 increase ratio in pyrolysis above 500 °C was more than 40% in the presence of catalyst. Consequently, this study showed the great potential of nano-NiO as a high-efficiency catalyst in recovering energy from biomass.


Assuntos
Níquel , Pirólise , Biomassa , Óxidos , Chuva , Árvores
5.
Onco Targets Ther ; 12: 8701-8714, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31695428

RESUMO

PURPOSE: Regulator of G-protein signaling (RGS) proteins are GTPase-activating proteins that target the α-subunit of heterotrimeric G proteins. Many studies have shown that RGS proteins contribute to tumorigenesis and metastasis. However, the mechanism in which RGS proteins, especially RGS4, affect the development of non-small cell lung cancer (NSCLC) remains unclear. The aim of this study was to characterize the role of RGS4 in NSCLC. METHODS: RGS4 expression in NSCLC tissues was assessed using an immunohistochemistry tissue microarray. Additionally, RGS4 was knocked down using short-hairpin RNA to assess the regulatory function of RGS4 in the biological behaviors of human NSCLC cell lines. A xenograft lung cancer model in nude BALB/c mice was established to study whether RGS4 knockdown inhibits cancer cell proliferation in vivo. RESULTS: We observed an increase in RGS4 protein levels in NSCLC samples. RGS4 knockdown inhibited cell proliferation and induced apoptosis in H1299 and PC9 cell lines, but did not affect cell migration. Moreover, we found that RGS4 negatively regulated the expression of microRNA-16 (miR-16), a tumor suppressor. The inhibition of miR-16 resulted in upregulated RGS4 expression. We also found that RGS4 regulated the expression of brain-derived neurotrophic factor (BDNF) and activated the BDNF-tropomyosin receptor kinase B signaling pathway. CONCLUSION: This study revealed that RGS4 overexpression positively correlated with the development of NSCLC. TDownstream RGS4 targets (eg, miR-16 and BDNF) might be involved in the development of NSCLC and may serve as potential therapeutic targets for its treatment.

6.
Bioprocess Biosyst Eng ; 42(11): 1721-1730, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31312897

RESUMO

Collecting microalgae from water with less energy and cost is significant to gain economic profit from microalgae harvesting and processing. Foam separation has certain advantages including low energy consumption, simple operation and easy maintenance of the equipment. Natural surfactants, compared to traditional surfactants, were used to harvest and separate the freshwater microalgae Desmodesmus brasiliensis by foam separation. Results showed a recovery percentage of 93.6% and an enrichment ratio of 23.1 with the natural surfactant cocamidopropyl betaine (CAPB), suggesting that this low-cost surfactant can be applied to microalgae biomass recovery on a commercial scale using foam separation with no negative effect on the content of microalgae chlorophyll, carotenoid or protein.


Assuntos
Betaína/análogos & derivados , Clorofíceas/citologia , Água Doce/microbiologia , Microalgas/citologia , Microalgas/isolamento & purificação , Tensoativos/química , Betaína/química , Floculação
7.
BMC Cancer ; 17(1): 140, 2017 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-28209128

RESUMO

BACKGROUND: Dysregulation of microRNAs (miRNAs) is actively involved in the pathogenesis and tumorigenicity of colorectal cancer (CRC). miR-296 was found to play either oncogenic or tumor suppressive role in human cancers. However, the status of miR-296 and its function in CRC remain unknown. METHODS: The expression of miR-296 was confirmed by qRT-PCR in CRC tissues and cells, and its level was altered by corresponding miRNA vectors. Wound healing and Transwall assays were performed to detect the migration and invasion of CRC cells. The levels of proteins were measured using immunoblotting, immunohistochemistry and immunofluorescence. RESULTS: Underexpression of miR-296 was disclosed in CRC tissues and cells. Its decreased level was evidently correlated with adverse clinical parameters and poor prognosis of CRC patients. In vitro experiments indicated that miR-296 inhibited CRC cell migration and invasion. Mechanically, miR-296 inhibited the epithelial-mesenchymal transition (EMT) of CRC cells. A negative correlation between miR-296 and S100A4 expression was observed in CRC tissues. Luciferase reporter assays indicated that miR-296 inversely regulated the luciferase activity of 3'-UTR of S100A4. Herein, S100A4 was found to be a downstream molecule of miR-296 in CRC. Furthermore, S100A4 mediated the anti-metastatic effects of miR-296 on EMT, migration and invasion of CRC cells. CONCLUSIONS: miR-296 functions as an anti-metastatic factor mainly by suppressing S100A4 in CRC. It potentially acts as a prognostic predictor and a drug-target for CRC patients.


Assuntos
Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Transição Epitelial-Mesenquimal/genética , MicroRNAs/genética , Proteína A4 de Ligação a Cálcio da Família S100/genética , Adulto , Idoso , Linhagem Celular Tumoral , Colo/química , Colo/metabolismo , Neoplasias Colorretais/química , Feminino , Técnicas de Silenciamento de Genes , Histocitoquímica , Humanos , Masculino , MicroRNAs/análise , MicroRNAs/metabolismo , Pessoa de Meia-Idade , Metástase Neoplásica/genética , Reação em Cadeia da Polimerase em Tempo Real , Proteína A4 de Ligação a Cálcio da Família S100/análise , Proteína A4 de Ligação a Cálcio da Família S100/metabolismo
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