Effects of Preharvest Shading on Dynamic Changes in Metabolites, Gene Expression, and Enzyme Activity of Three Tea Types during Processing.

Preharvest shading significantly influences tea flavor. However, little attention has been given to the mechanism of shading on metabolites, genes, and enzymes in the processing of different tea types. Our study identified 1028 nonvolatile metabolites covering 10 subclasses using a widely targeted metabolome. The results show that shading had a greater effect on the compositions of amino acids, flavonoids, and theaflavins in tea leaves. The combined transcriptomics and enzyme activity analysis results indicate that the upregulated expression of asparagine, aspartate, and tryptophan synthesis genes and proteolytic enzymes promoted the accumulation of amino acids. The downregulated enzyme genes resulted in the reduction of nongalloylated catechins and flavonoid glycosides. Simultaneously, the accumulation of TFs in shaded tea was due to the enhanced enzymatic activities of polyphenol oxidase and peroxidase during processing. Theaflavin-3-3'-di-O-gallate was also significantly positively correlated with the antioxidant and hypoglycemic activities of shaded tea. The results contribute to a better understanding of how preharvest treatments influence summer tea quality.

Method for umbilical cord blood-derived basophils by FCM.

We have devised a method for the purification of human basophils from umbilical cord blood by FCM. Umbilical cord blood was collected from six healthy, full-term deliveries. After separation of red blood cells, mononuclear cells were isolated by Ficoll-Hypaque. Six samples followed by positive selection using flowcytometry (FCM) for CD203c(+)CD45(int+) cells. Purity and recovery of cells were measured. Purity and recovery of basophils by FCM with CD203c(+)CD45(int+) markers were 95.02 +/- 2.94% and 61.42 +/- 5.95%. Cell sorting for CD203c(+)CD45(int+) cells by FCM is an improved method for obtaining pure umbilical cord blood-derived basophils. We established cord blood-derived basophil purification technique as a source from which active basophils can be isolated for immunochemical characterization.

[Study on genetic phenotype of asthma through examination of neonates' cord blood cells and interleukin-4].

OBJECTIVE: To identify the genetic phenotypes of asthma based on the examination of the umbilical cord blood from neonates of the mothers with asthma. METHODS: Umbilical cord blood was collected from 39 asthmatic lying-in women and 46 healthy lying-in women. Eosinophils and basophils absolute counts, total immunoglobulin E, and interleukin (IL)-4 were examined. Mononuclear cells (MNCs) from the umbilical cord blood were cultured. IL-4 in the supernatant was test by ELISA. White cells were collected from the umbilical cord blood. Basophils and T lymphocytes were purified, cultured, and stimulated by hyper osmotic mannitol. RT-PCR was used to test the mRNA expression of IL-4 in the supernatant. RESULTS: There were no significant differences in the counts of basophils and eosinophils, total IgE, and IL-4 in the cord blood, and IL-4 in the supernatant of cultured MNCs. After stimulation of hyper-osmotic mannitol, equine anti-human IgE, and dust mite the HBDT positive rates were 64.10%, 17.95%, and 0% respectively in the neonates of asthmatic women group, the former two rates being both significantly higher than those in the neonates of healthy women group (15.22% and 2.17% respectively, P < 0.05 and P < 0.025). After stimulation of hyper-osmotic mannitol, IL-4 mRNA was markedly expressed in the purified basophils of both groups and was almost not expressed in the purified eosinophils of both groups. CONCLUSION: There is qualitative abnormalities in the basophils from the cord blood of neonates of asthmatic mothers that strongly express IL-4 mRNA. Such characteristics may be an asthma-related genetic phenotype.