Effect of Fe(III) Species on the Stability of a Water-Model Oil Emulsion with an Anionic Sulfonate Surfactant as an Emulsifier.

The stability of an emulsion has an important effect on enhancing oil recovery. However, the effect of ions with different valences on the stability of the emulsion emulsified by an ionic surfactant is not fully understood. In this study, the effects of Fe(III) species on the stability, microscopic morphology of droplets, interfacial properties, and rheological properties of water-model oil emulsions emulsified by sodium dodecyl benzenesulfonate (SDBS) were explored. The effect of Fe(III) species on the stability of a W/O crude oil emulsion was also explored. The stability experiment results show that the addition of the Fe(III) species impairs the stability of the model oil-in-water (O/W) emulsion, in which the O/W model oil emulsion is inverted to a water-in-model oil (W/O) emulsion at ∼99 ppm. With the increase of Fe(III) species concentration, stable W/O model oil and W/O crude oil emulsions are obtained. The rheological results indicated that the existence of the Fe(III) species has a remarkable effect on the viscosity and viscoelastic behaviors of the water-model oil emulsion. The calculation results based on Derjaguin-Landau-Verwey-Overbeek (DLVO) theory are in accord with the stability experiment results. Furthermore, the addition of EO groups makes the phase inversion point appear at a higher Fe(III) species concentration, forming a more stable W/O model oil emulsion and a more unstable O/W model oil emulsion. The experimental results are helpful to comprehensively understand the effect of Fe(III) species on the stability of an emulsion emulsified by an anionic sulfonate surfactant, which can help to enhance the oil recovery.

[MicroRNA-21 correlates TGF-ß1 pathway of pancreatic ductal adenocarcinoma].

OBJECTIVE: To conduct genetic analysis of pancreatic ductal adenocarcinoma tissues and analyze the correlation between targeted microRNA (miRNA) and pathways in pancreatic ductal adenocarcinoma.
 Methods: We collected 19 samples of peripheral venous blood serum from patients with pancreatic ductal adenocarcinoma in Hainan Provincial Hospital of Chinese Medicine, and also collected 21 blood serum samples as a control group of non-pancreatic ductal adenocarcinoma. We used the bioinformatics analysis of literature GCBI data platform for screening and analyzing the genetics of pancreatic ductal adenocarcinoma samples. Through GCBI data platform of hierarchy clustering analysis and the enrichment of gene function analysis, the relevant miRNA was screened as a research object in patients with pancreatic ductal adenocarcinoma. The miRNA was screened by literature analysis and pancreatic cancer gene analysis. Real-time PCR and Western blotting were carried out to study the relationship between the selected miRNA and TGF-ß1 by overexpression and suppression of the gene in pancreatic ductal adenocarcinoma cells.
 Results: MiRNA-21 was screened as a gene associated with pancreatic ductal carcinoma via hierarchy clustering analysis and gene function analysis. MiRNA-21 was highly expressed in the pancreatic ductal carcinoma patients. Expressions of TGF-ß1 were inhibired in miRNA-21 overexpressed PANC-1. While the expression of miRNA-21 was inhibited, TGF-ß1 expression increased obviously.
 Conclusion: MiRNA-21 is highly expressed in patients with pancreatic ductal adenocarcinoma, can regulate the expression of TGF-ß1, which may be a mechanism of miRNA-21 in pancreatic ductal adenocarcinoma.