RESUMO
In recent years, micro/nano-scaled separation technique has attracted increasing attention due to its inherent advantages. The porous layer open tubular ( PLOT) capillary column is an important microcolumn form. Comparied to wide-bore PLOT capillary columns ( inner diameter >25 μm ) , the PLOT capillary columns with a narrow inner diameter yield higher separation efficiency and lower reagent consumption. In this paper, the preparation methods for porous layer open tubular capillary columns with narrow inner diameter, less than or equal to 25 μm, are reviewed. Detection techniques combined with mass spectrometry and their applications in liquid chromatography are also disussed.
RESUMO
Objective:To investigate the mechanism of β-carotene anti-inflammatory on intestinal epithelial cells.Methods:The piglet jejunum epithelium(IPEC-J2)cell line was used as an cell model.The cells were divided into 4 groups[control group,β-carotene group,β-carotene pre-protective group and Lipopoly-saccharide(LPS)group].The control group was not treated,β-carotene group and β-carotene pre-protective group were pretreated with β-carotene.Lipopoly-saccharide(LPS)and β-carotene pre-protective groups were stimulated with LPS.The cell viability was detected by MTT.Western blot was performed to detect the expression of Occludin,Claudin4 and ZO-1 tight junction proteins.Results:The expression of IPEC-J2 cell tight junction protein in LPS group were significantly lower than that of the control group(P<0.05).The expression of tight junction protein in β-carotene pre-protective group was significantly higher than that in LPS group(P<0.05).Conclusion:Increasing the expression of tight junction proteins may be one of the ways that anti-inflammatory effect of β-carotene in jejunum epithelial cells.