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The experiment obtained high antagonistic strains with antibacterial activity from soil samples, and the preliminary bacteriostasis of fermentation active products was studied. The results showed that the fermentation broth numbered LP10 had a good antibacterial effect on indicator bacteria. After morphological characteristics, physiology and biochemistry and 16S rDNA comparison, a phylogenetic tree was established and identified, and the bacterium was Bacillus Dowii. The experiment indicates that the antibacterial substance has the strongest activity at 30 °C and it is stable below 90 °C, the strongest activity is at pH value 8, the strongest activity is at UV time of 6 h, the best storage temperature is 25 °C, and the solubility of the active substance in benzene solvent is greater. [ABSTRACT FROM AUTHOR]

Compounds with redox activities have appealing applications in catalytic, electronic and magnetic properties, but the redox inert of polyoxoniobates (PONbs) significantly limits their applications for a long time. In this work, we are able to integrate organophosphate and lanthanide cluster into PONb to create the first family of inorganic-organic hybrid organophosphate-Ln-PONb composite clusters. These novel species not only present the first family of redox active PONbs that can be reduced to form long-lived "heteropoly blues" under ambient conditions, but also a new photochromic system. More importantly, the analyses of the electronic configurations and photochromic properties for a series of designed proof-of-concept PONbs models allow us to discover a D-f-A electron transfer mechanism, that is, photoinduced electron is transferred from a photosensitive organophosphate electron donor (D) to the Nb V electron acceptor (A) through the unoccupied 4 f-orbitals of Ln (f). This work paves the way for developing diverse PONb-based redox materials and expanding the possibility of the applications of PONbs in the redox chemistry., (© 2023 Wiley-VCH GmbH.)

Objective: To extract microRNA(miRNA) from Glycyrrhiza uralensis(liquorice) decoction and to explore its effect on mmune cells., Methods: With dried processed liquorice, the water decoction was prepared according to the conventional method and subsequently concentrated by rotary evaporation. The concentrated decoction was further freeze-dried by freeze dryer, and miRNAs were extracted with Plant MicroRNA Extraction Kit. The extracted miRNA was digested by DNase I and then analyzed through the agarose gell electrophoresis. The PBMC was isolated from healthy volunteers and treated respectively by liquorice water extract, glycyrrhizic acid, glycyrrhetic acid and liquorice miRNAs. After 24 hours, the cells numbers were counted, and the changes of cell morphology were observed. The expression of CD3, CD56 and HLA-DR were analyzed by flow cytometry to identify the change of cell subsets in PBMC., Results: miRNAs could be extracted from the decoction of dried liquorice which further confirmed the stability of miRNAs. The in vitro culture experiment showed that,compared with the controls, PBMC treated with liquorice miRNAs appeared apparent cell aggregation and increased cell number and HLA-DR+ cells proportion., Conclusion: The miRNAs are successfully extracted from the freeze-dried decoction of dried liquorice. It is indicated that liquorice miRNAs have significant stimulative effects on the growth of PBMC and HLA-DR+ cells subset.

Objective: To investigate the apoptotic effect of oridonin in human pancreatic cancer cells PANC-1, and to explore the underlying mechanism., Methods: MTT assay was used to measure the cell viability. Apoptosis was determined by confocal laser scanning microscope after Hoechst 33342 staining and flow cytometry analysis after PI staining. The regulation of JNK and p38 MAPK signaling pathway proteins was examined by Western blot analysis., Results: Treatment with oridonin for 24 h resulted in a marked decrease in cell viability in a dose-dependent manner. The IC50 value was determined as 49.80 μmol/L for 24 h. After treatment with 50 micromol/L and 80 μmol/L oridonin for 24 h, typical apoptotic nucleus alterations were observed with confocal laser scanning microscope and apoptotic rates of PANC-1 cells increased by flow cytometry analysis. Treatment with 80 μmol/L oridonin down-regulated protein expression of JNK, p38 and increased the expression of p-JNK, p-p38. Furthermore, 80 μmol/L oridonin treatment decreased the expression of down-stream proteins Caspase-9, Caspase-3 and PARP in the apoptotic pathway as well as activated the cleavage of Caspase-9., Conclusion: Oridonin can induce apoptosis of PANC-1 cells through JNK and p38 MAPK pathway proteins.

Objective: To analyze the bioactive components in Jatropha curcas leaves using gas chromatography-mass spectrometry (GC-MS)., Methods: The bioactive components were extracted from J. curcas leaves by supercritical fluid CO2 extraction and analyzed by using GC-MS., Results: Seventy peaks were detected by GC-MS, and 43 compounds were identified (61.43%). Among the identified compounds, 16 had a content of more than 1%, and the total contents of these 16 compounds reached 81.36%. The four most abundant components were 22,23-dihydro-stigmasterol (16.14%), alpha-tocopherol (15.18%), beta-amylin (7.73%) and dotriacontanol (7.02%). The content of gamma-tocopherol reached 2.88% and vitamin E reached 18.06% in the extract., Conclusion: J. curcas leaves contain multiple compounds with anti-tumor, anti-virus and antimicrobial activities.

Objective: To investigate effect of tumor-specific T cell receptor gene transfection on memory T cell differentiation in vitro., Methods: TCRVbeta7.1 gene was transferred into peripheral blood mononuclear cells (PBMCs) obtained from healthy adults, and the expression of Vbeta7.1 was detected by flow cytometry before and after the transfection. Memory T cell differentiation was induced by stimulation with the hepatocarcinoma cell line BEL-7402 in vitro. The expression of surface molecules CD45RO, CD45RA and CCR7 was analyzed by flow cytometry to identify the phenotype and subsets of the memory T cells. Fluorescence-activated cell sorting was performed to detect the apoptosis of the tumor cells, and enzyme-linked immunoabsorbent assay was used to determine the production of interferon-gamma (IFN-gamma) for assessing the immune function of the memory T cells., Results: Flow cytometry showed that TCRVbeta7.1 gene was efficiently expressed after transfection. After stimulation by the tumor cells in vitro, the expression of CD45RO in TCRVbeta7.1 gene-modified T cells increased gradually, and analysis of the coexpression of CD45RA and CCR7 revealed that the effector memory T cells constituted the majority of the differentiated memory T cells. The apoptotic rate of the tumor cells induced by the T cells increased significantly with also obviously increased INF-gamma secretion in the memory T cells., Conclusion: Tumor-specific TCRVbeta7.1 gene transfection can promote the differentiation of the memory T cells, the majority of which belongs to effector memory T cells that perform immune functions by inducing apoptosis and cytokine secretion.