Controlling the main source of green tides in the Yellow Sea through the method of biological competition.

Macroalgal blooms have become a serious threat to public health, fisheries, ecosystems, and global economies. Since 2007, in the Yellow Sea, China, Ulva green tides have occurred for 15 consecutive years. However, effective control methods are limited. Ulva prolifera attached to Neopyropia aquaculture rafts are believed to be the main source of blooms, therefore eliminating Ulva from rafts could effectively prevent and control blooms. We investigated this phenomenon and showed that macroalgae germination was significantly inhibited by dried Neopyropia yezoensis at concentrations of 1.2, 2.4, and 4.8 g DW-1. Also, the inhibitory effects of dried N. yezoensis toward U. prolifera gametes at 2.4 and 4.8 g DW-1 were >90% at day 21. N. yezoensis culture filtrates and thalli were also used to determine dose-dependent inhibition effects on U. prolifera gamete germination. Both were potent and significantly inhibited germination at 1.75-7 g FW-1; the inhibitory effect 7 g FW-1 was >90% at day 21. As N. yezoensis thalli exhibited high inhibitory effects in laboratory experiments, we also performed field studies. N. yezoensis on ropes displayed high inhibitory effects on Ulva attachment and growth. Thus N. yezoensis powder, culture filtrates, and thalli displayed strong inhibitory effects on U. prolifera gametes, suggesting N. yezoensis attachment to ropes could be used to control green tides at the source.

Identification of key pathways and hub genes in the myogenic differentiation of pluripotent stem cell: a bioinformatics and experimental study.

BACKGROUND: The regeneration of muscle cells from stem cells is an intricate process, and various genes are included in the process such as myoD, mf5, mf6, etc. The key genes and pathways in the differentiating stages are various. Therefore, the differential expression of key genes after 4 weeks of differentiation were investigated in our study. METHOD: Three published gene expression profiles, GSE131125, GSE148994, and GSE149055, about the comparisons of pluripotent stem cells to differentiated cells after 4 weeks were obtained from the Gene Expression Omnibus (GEO) database. Common differentially expressed genes (DEGs) were obtained for further analysis such as protein-protein interaction (PPI) network, Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), and GSEA analysis. After hub genes and key pathways were obtained, we manipulated in vitro cell research for substantiation such as immunohistochemical staining and semi-quantitative analysis and quantitative real-time PCR. RESULTS: A total of 824 DEGs including 350 upregulated genes and 474 downregulated genes were identified in the three GSEs. Nineteen hub genes were identified from the PPI network. The GO and KEGG pathway analyses confirmed that myogenic differentiation at 4 weeks was strongly associated with pathway in cancer, PI3K pathway, actin cytoskeleton regulation and metabolic pathway, biosynthesis of antibodies, and cell cycle. GSEA analysis indicated the differentiated cells were enriched in muscle cell development and myogenesis. Meanwhile, the core genes in each pathway were identified from the GSEA analysis. The in vitro cell research revealed that actin cytoskeleton and myoD were upregulated after 4-week differentiation. CONCLUSIONS: The research revealed the potential hub genes and key pathways after 4-week differentiation of stem cells which contribute to further study about the molecular mechanism of myogenesis regeneration, paving a way for more accurate treatment for muscle dysfunction.

[Running Condition and Bacterial Community Associated with the Partial Nitritation System].

In partial nitritation process, the sludge concentration was higher than 4000 mg x L(-1), DO was less than 0.2 mg x L(-1), the temperature of 15-29 degrees C, the reactor HRT of 4.6 h, and the circulation ratio was 75%, not only the microbial biomass reached the highest value but also the ratio of nitrite to ammonium of the effluent could be controlled at approximate 1.0 by adjusting the dissolved oxygen concentration. A quantitative PCR and the 16S rRNA genes clone library results demonstrated that ammonia-oxidizing bacteria were the dominant among nitrite-oxidizing bacteria at low dissolve oxygen concentration, that the bacteria promoted the running of the partial nitritation. Compared with conventional nitrification systems, in partial nitritation process, Nitrobacter and Nitrospira could not be detected among the system, and abundance of Planctomycetes was higher in partial nitritation process than that of conventional nitrification systems. Phylogenetic analysis of bacterial amoA gene sequences suggested that ammonia-oxidizing bacteria of the partial nitritation system was dominated by Nitrosomonas sequences, so partial nitritation is to be feasible technically and economically.