Precise Detection on Cell-Cell Fusion by a Facile Molecular Beacon-Based Method.

Cell-cell fusion studies provide an experimental platform for evaluating disease progression and investigating cell infection. However, to realize sensitive and quantitative detection on cell-cell fusion is still a challenge. Herein, we report a facile molecular beacon (MB)-based method for precise detection on cell-cell fusion. By transfection of the spike protein (S protein) and enhanced green fluorescent protein (EGFP) in HEK 293 cells, the virus-mimicking fusogenic effector cells 293-S-EGFP cells were constructed to interact with target cells. Before mixing the effector cells with the target cells, the glyceraldehyde-3-phosphate dehydrogenase (GAPDH) expression in 293-S-EGFP cells was silenced, and the MB for GAPDH mRNA detection was delivered into the GAPDH silenced 293-S-EGFP cells. Once cell-cell fusion occurred, MB migrated from the GAPDH silenced effector cells to the target cells and hybridized with GAPDH mRNA in the target cells to induce fluorescence emission. The cell-cell fusion can be easily visualized and quantitated by fluorescence microscopy and flow cytometry. The fluorescence intensity is strongly dependent on the number of fused target cells. This MB-based method can easily identify the differences in the cell fusions for various target cells with different angiotensin-converting enzyme 2 (ACE2) and transmembrane serine protease 2 (TMPRSS2) expression levels, resulting in dramatically different fluorescence intensities in fused target cells. Our study provides a convenient and efficient quantitative detection approach to study cell-cell fusion.

[Study on medication regularity of chronic atrophic gastritis in Beijing-Tianjin-Hebei region based on latent structure model].

To explore the etiology, pathogenesis, distribution of syndromes and the rule of medication of chronic atrophic gastritis(CAG) in Beijing-Tianjin-Hebei region based on the latent structure model. Chronic atrophic gastritis of 279 cases in Beijing-Tianjin-Hebei region were extracted from the established database of spleen and stomach diseases of famous veteran Chinese medicine experts. The latent structure models of symptoms and drugs of chronic atrophic gastritis were constructed by using Lantern 3.1.2 software, and the latent structure models were interpreted. SAS 10.0 software was used to mine association rules of drugs and symptoms. The constitutional characteristics of patients with chronic atrophic gastritis in Beijing-Tianjin-Hebei region were "turbid toxin and damaging Yin". The common syndromes were turbid toxin, deficiency of stomach Yin, stagnation of liver and stomach, stagnation of liver and stomach Qi, obstruction of stomach collaterals and blood stasis, and weakness of spleen and stomach. Common medicines are Lobeliae Chinensis Herba, Scutellariae Barbatae Herba, Amomi Fructus Rotundus, Amomi Fructus, Poria, Isatidis Radix, Artemisiae Scopariae Herba, Scorpio, Coptidis Rhizoma, Lilii Bulbus, Linderae Radix, Phragmitis Rhizoma, Ophiopogonis Radix, Pogostemonis Herba, Eupatorii Herba, Magnoliae Officinalis Cortex, Aurantii Fructus Immaturus. Common prescriptions are Baihe Wuyao Powder, Danggui Shaoyao Powder, Xiaoyao Pills, Xiangsu Powder, Dachengqi Decoction, Zuojin Pills, Qingzhong Decoction, Zhishi Daozhi Pills, etc. The application of latent structure model and correlation analysis in the empirical study of famous and veteran Chinese medicine experts is in line with the research direction of modern Chinese medicine "traditional Chinese medicine + X". The conclusions obtained effectively tap the experience of famous and veteran TCM experts, and provide a data and visual clinical reference and prescription compatibility for young TCM physicians in the treatment of chronic atrophic gastritis based on syndrome differentiation.

[Aerobic Degradation Characteristics of the Quinoline-Degrading strain Ochrobactrum sp. and Its Bioaugmentation in Coking Wastewater].

Quinoline is one of the common refractory organic pollutants in coking wastewater. An aerobic bacterial strain KDQ3 capable of utilizing quinoline as the sole source of carbon, nitrogen and energy was isolated from activated sludge of a coking wastewater treatment plant. The morphological properties and the 16S rDNA sequence identified KDQ3 as Ochrobactrum sp.. The optimized temperature and initial pH for quinoline degradation were 37℃ and 7.0-8.0, and the degradation kinetics fit with Haldane's model. KDQ3 could degrade 200 mg·L-1 quinoline in the presence of 10.4 mg·L-1 hexavalent chromium. In addition, KDQ3 was able to degrade quinoline in real coking wastewater of aerobic tank and improve the removal of COD, indicating that KDQ3 had the potential of bioaugmentation for removal of quinoline from coking wastewater.

[Biodiversity of Thiocyanate-degrading Bacteria in Activated Sludge from Coking Wastewater].

Thiocyanate (SCN-) is one of the main sources of COD in coking wastewater, and SCN- removal efficiency of the aerobic unit impacts the requirement of discharging standard. Microbial population in the activated sludge plays an important role in SCN- removal of coking wastewater treatment. However, the community structure has rarely been reported. Using SCN- as the sole carbon and energy source, the removal of 100 mg·L-1,300 mg·L-1 and 600 mg·L-1 SCN- by activated sludge was studied and 454 sequencing technology was applied to investigate the biodiversity of SCN--degrading bacteria. The results showed that 100-600 mg·L-1 SCN- could be effectively removed by acclimated activated sludge, the higher SCN- concentration, the higher removal efficiency, but the lower bacterial community diversity indices. The bacterial communities in initial and acclimated sludge samples were mainly composed of Proteobacteria, Bacteroidetes, Chlorobi, Planctomycetes, Acidobacteria, Nitrospira, Firmicutes and Unclassified bacteria. Bacteroidetes and Proteobacteria were dominant phyla in the sludge. Thiobacillus was responsible for SCN- biodegradation in coking wastewater, and its abundance in three sludge samples was 3.07%, 8.63% and 0.27%, respectively. When the concentration of SCN- was less than 300 mg·L-1, Thiobacillus was the main degrading bacteria. While at 600 mg·L-1 SCN-, low-abundance degrading bacteria might have synergistic degradation effect. These results have important significance for revealing SCN- removal mechanism in the coking wastewater treatment.

Structural characterization of a series of 10-carbon sugar derivatives by electrospray-ionization MSn mass spectrometry.

Electrospray-ionization MSn mass spectrometry (ESI-MSn) with low-energy, collision-induced dissociation (CID) was used to establish the fragmentation behavior of sodium ion adducts of higher-carbon amino spiro-sugar derivatives. Their fragmentation pathways are proposed on the basis of the MSn studies and deuteration experiments. Some of the rings of these derivatives opened under the conditions of electrospray ionization. Novel fragmentations were observed and their mechanisms are proposed. This study demonstrates the power of modern mass spectrometry for rapid elucidation of the structure of higher-carbon sugar derivatives.