RESUMO
Owing to the tissue characteristics of tendons with few blood vessels and cells, the regeneration and repair of injured tendons can present a considerable challenge, which considerably affects the motor function of limbs and leads to serious physical and mental pain, along with an economic burden on patients. Herein, we designed and fabricated a dipeptide hydrogel (DPH) using polypeptides P11-4 and P11-8. This hydrogel exhibited self-assembly characteristics and could be administered in vitro. To endow the hydrogel with differentiation and regeneration abilities, we added different concentrations of growth differentiation factor 5 (GDF5) to form GDF5@DPH. GDF5@DPH promoted the aggregation and differentiation of tendon stem/progenitor cells and promoted the regeneration and repair of tendon cells and collagen fibers in injured areas. In addition, GDF5@DPH inhibited inflammatory reactions in the injured area. Owing to its injectable properties, DPH can jointly inhibit adhesion and scar hyperplasia between tissues caused by endogenous inflammation and exogenous surgery and can provide a favorable internal environment for the regeneration and repair of the injured area. Overall, the GDF5@DPH system exhibits considerable promise as a novel approach to treating tendon injury.
RESUMO
A double cropping system has been commercially adopted in southern China, where there is abundant sunshine and heat resources. In this viticulture system, the first growing season normally starts as a summer cropping cycle; then, the vine is pruned and forced, resulting in a second crop in winter. Due to climate differences between the summer and winter growing seasons, grape ripening progression and flavonoid metabolism vary greatly. Here, the metabolites and transcriptome of flavonoid pathways were analyzed in grapes grown under two growing seasons at different stages. Notably, the winter cropping cycle strongly increased flavonoid levels by several times in comparison to summer grapes, while the summer season took a major toll on anthocyanin and flavonol accumulation, since the winter cropping greatly triggered the expression of upstream genes in the flavonoid pathway in a coordinated expression pattern. Moreover, the ratio of VviF3'5'Hs (flavonoid 3'5'-hydroxylase) to VviF3'Hs (flavonoid 3'-hydroxylase) transcript levels correlated remarkably well with the ratio of 3'5'-substituted to 3'-substituted flavonoids, which was presumed to control the flux of intermediates into different flavonoid branches. On the other hand, the phenological phase also varied greatly in the two crops. Compared to summer cropping, winter growing season accelerated the duration from budburst to veraison, therefore advancing the onset of ripening, but also prolonging the duration of ripening progression due to the purposes to harvest high-quality grapes. The differential expression pattern of hormone-related genes between the two cropping cycles might explain this phenomenon.
RESUMO
A novel high-throughput method was established for rapid screening of a large numbers of Aspergillus fumigatus (A. fumigatus) mutants with high chitosanase production under acidic culture condition by exploiting the fact that iodine can be used as the indicator to stain chitosan but is ineffective for chitooligosaccharides. The mutant population was generated by irradiating A. fumigatus CICC 2434 with Co(60)-γ rays. Mutants were cultured on acidic plates containing colloidal chitosan and preliminary screened according to diameter of haloes formed around colonies. Then, chitosanase production of the isolates were verified by dinitrosalicylic acid assay. Lastly, molecular masses on enzymolysis products of isolated mutants were rapidly compared by aniline blue plate assay. Using this method, the mutant strain Co-8 was selected, which had chitosanase activity of 24.87 U/mL (increased by 369.2 % as compared to that of its parental strain).Taking together, the method is easy, efficient and particularly suited to rapid screen acidophilic fungal strains with high chitosanase-production.
