Human glioma is a highly fatal tumor with a significant feature of immune suppression. The functions of PD-L1 refer to co-simulation and immune regulation. To investigate expression and functional activity of PD-L1 in human glioma cell in vivo and in vitro. Expressions of PD-L1mRNA and protein in the human glioma cell line were analyzed with quantitative RT-PCR and flow cytometer; and then expression of PD-L1 in tissue specimens of 10 glioma patients was treated with immunohistochemical analysis; glioma cell and allogeneic CD4+ and CD8+ T cells were co-cultured, and cytokine IFN-γ, IL-2 and IL-10 in cultured supernatant fluid were determined with ELISA; upon blocking the interaction between glioma cell and the immune cell with PD-L1 monoclonal antibody (5H1), surface markers on immune cells were analyzed using flow cytometer. All human glioma cell lines constitutively expressed PD-L1, and IFN-γ induced glioma cell to highly express PD-L1. It was shown through immunohistochemical analysis that glioma specimen expressed PD-L1, while expression of PD-L1 was not observed in normal tissue and normal human brain near the tumor location. The release of IFN-γ and IL-2 was inhibited, while IL-10 was increased slightly. Glioma cell may escape from immune recognition and injury with the help of PD-L1, which is a significant pathogenic mechanism of glioma.
Shrimp meat is prone to autolysis and decay due to the abundance of endogenous enzymes and contamination from microorganisms. HVEF freezing can slow the spoilage of shrimp, producing small and uniform ice crystals, resulting in less damage to muscle tissue. In this study, HVEF technique was used to freeze the shrimp (Solenocera melantho), and the UPLC-MS metabolic technique was used to investigate the metabolites of frozen shrimp meat. Compared with the control group, 367 differential metabolites were identified in the HVEF group. Mapping them to the KEGG database, there were 108 with KEGG ID. Purine metabolism and pyrimidine metabolism were the most enriched pathways. In addition, phosphatidylcholines (PCs), inosine (HxR), and l-valine were identified as potential biomarkers associated with lipid, nucleotide, and organic acid metabolism, respectively. Overall, HVEF can improve freezing quality of shrimp meat by slowing down the metabolism of substances in the muscle of S. melantho.
Pyrethroids are common contaminants in water bodies. In this study, an efficient mussel shell-based adsorbent was prepared, the effects of factors (calcination temperature, calcination time, and sieved particle size) on the pyrethroid adsorption capacity from calcined shell powder were investigated via Box-Behnken design, and the prediction results of the model were verified. By characterizing (scanning electron microscopy, X-ray diffraction, Fourier infrared spectroscopy, and Brunauer-Emmett-Teller measurements) the adsorbent before and after the optimized preparation process, the results showed that calcined shell powder had a loose and porous structure, and the main component of the shell powder under optimized condition was calcium oxide. The adsorption mechanism was also investigated, and the analysis of adsorption data showed that the Langmuir, pseudo second-order, and intra-particle diffusion models were more suitable for describing the adsorption process. The adsorbent had good adsorption potential for pyrethroids, the adsorption capacity of the two pesticides was 1.05 and 1.79 mg/g, and the removal efficiency was over 40 and 70% at the maximum initial concentration, respectively.
High level of aluminum content in Enteromorpha prolifera posed a growing threat to both its growth and human health. This study focused on exploring the factors, impacts, and process of removing aluminum from Enteromorpha prolifera using humic acid. The results showed that under experimental conditions of 0.0330 g·L-1 humic acid concentration, pH 3.80, 34 °C, and a duration of 40 min, the removal rate was up to 80.18%. The levels of major flavor components, proteins, and amino acids in Enteromorpha prolifera increased significantly after treatment, while polysaccharides and trace elements like calcium and magnesium decreased significantly. Infrared spectroscopy demonstrated that the main functional groups involved in binding with Al3+ during humic acid adsorption were hydroxyl, carboxyl, phenol, and other oxygen-containing groups. The adsorption process of Al3+ by humic acid was a spontaneous phenomenon divided into three key stages: fast adsorption, slow adsorption, and adsorption equilibrium, which resulted from both physical and chemical adsorption effects. This study provided a safe and efficient method in algae metal removal.