Effect of Cutting Styles on Quality and Antioxidant Activity of Stored Fresh-Cut Sweet Potato (Ipomoea batatas L.) Cultivars.

The effect of cutting styles (slice, pie, and shred) on the quality characteristics and antioxidant activity of purple and yellow flesh sweet potato cultivars during six days of storage at 4 °C was investigated. The results indicated that the sliced and pie samples showed no significant difference (p > 0.05) on the firmness, weight loss, and vitamin C content compared with the whole sweet potato in both cultivars during storage. The pie sample exhibited the highest wound-induced phenolic, flavonoid, and carotenoid accumulation and DPPH radical scavenging activity among the cuts in both cultivars. Moreover, the shredded sample showed significantly (p < 0.05) higher polyphenol oxidase (PPO) activity but lower total phenolic and flavonoid content and the lowest antioxidant activity among the samples. Thus, the finding of this study revealed that pie-cut processing has potential in improving the quality and increasing the antioxidant activity of fresh-cut purple and yellow flesh sweet potato cultivars while shredding accelerated the quality deterioration of both sweet potato cultivars.

The effect of siRNA inhibited tyrosine protein kinase Lck on the function of T cells in asthmatic mice / 中国医师杂志

Objective Using the technology of siRNA to inhibit gene expression of T cells'nonreceptor tyrosine protein kinase Lck in asthmatic mice,and to study the effect of siRNA inhibited Lck to the function of T cells in asthmatic mice.Methods The 21 - 23 bp RNA fragments of mouse T cell Lck were made by chemosynthesis.INTERFERinTMsiRNA Transfection Reagent was used as transfection reagent to transfect the siRNA into the spleen T cells of asthmatic mice for 48 hours.Then T cells were mixed with bone marrow dendritic cells (DC) of asthmatic mice for another 48 hours.Cell culture suspension was collected and the level of IL-4,IL-13,IL-2,INF-γ were detected with respondent ELISA kits; Western Blot was used to identify if the expression of Lck was blocked.Results The expression of Lck in T cells almost could not be detected in siRNA interference group.The levels of IL-4 and IL-13 in siRNA interference group( 10.19 ± 1.66,12.34 ±0.79) were lower than no-siRNA interference(28.06 ±2.88,27.87 ± 1.61 )and control group ( 22.07 ± 2.5 1,20.47 ± 2.37 ),and the difference was statistical significant ( P ＜0.01 ).Conclusions Special siRNA could block the expression of special gene,and Lck specific siRNA could block the activation and differentiation of T cells and reduce the secretion of inflammatory cytokines in asthmatic mice.

In vivo study of tyrosine protein kinase Lck inhibited by siRNA in T cells of asthmatic mice / 中国医师杂志

ObjectiveUsing the technology of siRNA to inhibit the gene expression of no-receptor　tyrosine protein kinase Lck in T cells of asthmatic mice,and to study the therapeutic effect of Lck specific　siRNA in asthmatic mice.MethodsReceptor tyrosine protein kinase Lck specific siRNA fragments were　taken from chemosynthesis.In vivo-jetPEITM was used to transfect the siRNA into mice body through tail　vein injection.The mice were killed 48 hours later,and the levels of IL-4,IL-17 in bronchoalveolar lavage　fluid (BALF) were detected with respondent ELISA kits.The change of inflammatory histopathology in lung　was observed with H.E.staining.The expression of Lck in lung was detected with immunohistochemistry　(IHC),and the level of Lck in lung tissue homogenate was detected with Western Blot.Results Compared with asthmatic group[ (234.68 ± 11.15 ) pg/ml,( 96.76 ± 8.28 ) pg/ml],the levels of IL-4,IL-17　[ (234.68 ± 11.15)pg/ml,(96.76 ±8.28) pg/ml] in the BALF of siRNA interference group decreased,　and the inflammation in the lung relieved.IHC indicated that the expression of Lck in lung decreased and　the level of Lck in lung tissue homogenate decreased ( P ＜ 0.05 ).Conclusions Lck specific siRNA　could reduce the level of IL-4,IL-17 in the lung tissues of asthmatic mice,and relieve the inflammatory reaction in lung.