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1.
J Environ Manage ; 354: 120302, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38401492

RESUMO

Tetrabromobisphenol A (TBBPA) that widely exists in soil and poses a potential threat to ecological environment urgently needs economically efficient remediation techniques. This study utilized both homogeneous Fe2⁺ solution and heterogeneous iron-based nanomaterials (chemically synthesized nano zero-valence iron (nZVI) and green-synthesized iron nanoparticles (G-Fe NPs)) to activate persulfate (PS) and assess their efficacy in degrading TBBPA in soil. The results demonstrate the superior performance of heterogeneous catalytic systems (WG-Fe NPs/PS (82.07%) and WnZVI/PS (78.32%)) over homogeneous catalytic system (WFe2+/PS (71.69%)), In addition, G-Fe NPs and nZVI effectively controlled the slow release of Fe2+. The optimization analysis using response surface methodology (RSM) reveal the remarkable significance of the experimental model based on the box-behnken design. RSM show that G-Fe NPs/PS exhibited optimal process parameters and predicted the maximum soil TBBPA degradation efficiency reaching 98.77%. The results of density functional theory calculations suggest that C-Br are the primary targets for electrophilic substitution reactions. Based on the f0 value and △G, the degradation pathway of TBBPA is inferred to involve a sequential debromination process, followed by the cleavage of intermediate carbon-carbon bonds and subsequent oxidation reactions. Hence, G-Fe NPs/PS not only facilitate waste resource utilization but also hold significant application potential.


Assuntos
Ferro , Bifenil Polibromatos , Poluentes Químicos da Água , Ferro/química , Solo , Oxirredução , Carbono , Poluentes Químicos da Água/química
2.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 53(3): 452-456, 2022 May.
Artigo em Chinês | MEDLINE | ID: mdl-35642154

RESUMO

Objective: To investigate the regulatory role of extracellular vesicles (EVs) carrying ATP binding cassette transporter G2 (ABCG2) on the drug resistance of lung adenocarcinoma cells and the relevant molecular mechanisms. Methods: A549 cells, human lung adenocarcinoma cells, were used to form cisplatin (or cis-Diaminedichloroplatinum, CDDP)-resistant lung adenocarcinoma cells, i.e., A549/CDDP cells. EVs from A549 and A549/CDDP cells were extracted by gradient centrifugation method and were hence named EVs 1 and EVs 2, respectively. The A549 cells were treated with EVs 1 and EVs 2 for 48 hours, and the cells were named A549-EVs 1 and A549-EVs 2 cells, respectively. A549/ ABCG2 cells were established by transfecting A549 cells with pCDNA3.1- ABCG2 recombinant plasmids. On the other hand, A549 cells transfected with empty vectors were named A549/pCDNA3.1 cells. MTT assay was conducted to calculate the 24-hour cell drug resistance index for CDDP. The ABCG2 gene expression in cells and EVs were assessed with real-time PCR. A549 and A549-EVs 2 cells were transplanted subcutaneously into nude mice, which were labeled the control group and the experimental group accordingly. After tumor formation, 3 mg/kg CDDP was intraperitoneally injected once a week for two times. The ABCG2 gene expression of subcutaneous transplanted tumor cells was examined by real-time PCR. The cell apoptosis rate of subcutaneous transplanted tumor cells was examined by flow cytometry. Results: Using the parental A549 cells as reference, the 24-h CDDP-resistance indexes of 549/CDDP, A549/ ABCG 2, A549/pCDNA3.1, A549-EVs 1, A549-EVs 2 cells were 7.17, 10.06, 1.02, 1.19 and 5.40, respectively. When comparing the ABCG2 gene expression levels in all cells and EVs, the findings were higher in A549/CDDP cells than those inA549 cells, higher in A549/ ABCG2 cells than those in A549/pCDNA3.1 or A549 cells, higher in EVs 2 than those in EVs 1, and higher in A549-EVs 2 than those in A549-EVs 1 cells ( P<0.01) . The volume of transplanted tumor and the ABCG2 gene expression level in the experimental group were higher than those in the control group, while the apoptosis rate was lower than that in the control group ( P<0.01). Conclusion: EVs carrying ABCG2 gene can regulate the drug resistance of lung adenocarcinoma cells.


Assuntos
Adenocarcinoma de Pulmão , Adenocarcinoma , Vesículas Extracelulares , Neoplasias Pulmonares , Adenocarcinoma/genética , Adenocarcinoma/patologia , Adenocarcinoma de Pulmão/genética , Animais , Linhagem Celular Tumoral , Cisplatino/farmacologia , Resistencia a Medicamentos Antineoplásicos/genética , Vesículas Extracelulares/metabolismo , Vesículas Extracelulares/patologia , Neoplasias Pulmonares/patologia , Camundongos , Camundongos Nus
3.
Front Plant Sci ; 13: 826902, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35360317

RESUMO

Rhizomes of the Polygonatum species are well-known in traditional Chinese medicine. The 2020 edition of Chinese Pharmacopoeia includes three different species that possess different pharmacological effects. Due to the lack of standardized discriminant compounds there has often been inadvertently incorrect prescriptions given for these medicines, resulting in serious consequences. Therefore, it is critical to accurately distinguish these herbal Polygonatum species. For this study, UPLC-Q-TOF-MS/MS based metabolomics was employed for the first time to discriminate between three Polygonatum species. Partial least squares discriminant analysis (PLS-DA) models were utilized to select the potential candidate discriminant compounds, after which MS/MS fragmentation patterns were used to identify them. Meanwhile, metabolic correlations were identified using the R language package corrplot, and the distribution of various metabolites was analyzed by box plot and the Z-score graph. As a result, we found that adenosine, sucrose, and pyroglutamic acid were suitable for the identification of different Polygonatum species. In conclusion, this study articulates how various herbal Polygonatum species might be more accurately and efficiently distinguished.

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