Single-cell transcriptomics reveals the heterogeneity of the decidual endothelial cells that participate in labor onset.

OBJECTIVE: To investigate the heterogeneity of decidual endothelial cells and their changes during delivery. PATIENTS AND METHODS: Single-cell RNA sequencing was used to characterize the transcriptomes of decidual endothelial cells before and after the onset of labor. RESULTS: Decidual endothelial cells (9748 cells) were divided into five subgroups with different functions according to differences in the transcriptome. The functions of cluster 5 were enriched in vascular development and response to growth factors. After the onset of labor, the activities of each cluster were different, including the interleukin 17 pathway and regulation of ERK1 and ERK2 cascade. The downregulated genes were related to scavenger receptor (cluster 5), which may reflect the process of endothelial activation. In terms of genetic changes, cluster 5 may be more actively involved in labor than the other clusters. CONCLUSIONS: Peripartum decidual endothelial cells are heterogeneous and participate in labor to varying degrees. One of the five subtypes of endothelial cells may be more actively involved in labor onset. Our findings may enable the assessment of decidual endothelial cells and labor onset.

MiR-374b reduces cell proliferation and cell invasion of cervical cancer through regulating FOXM1.

OBJECTIVE: Deregulation of microRNAs (miRNAs) has been identified as critical event in tumor initiation and progression. We aimed to explore the role of miR-374b in cervical cancer progression. PATIENTS AND METHODS: MiR-374b expression was detected using qRT-PCR in cervical cancer tissues compared with normal counterparts. Cell proliferation and invasion ability were detected using Cell Counting Kit-8 (CCK8) cell proliferation and transwell invasion assay. Dual luciferase reporter assay, qRT-PCR, and Western blot analysis were used to demonstrate that FOXM1 was a target of miR-374b. RESULTS: We demonstrated that downregulation of miR-374b was frequently examined in cervical cancer tissues compared with normal counterparts. Furthermore, we showed the lower miR-374b expression associated with lymph node metastasis and advanced FIGO stage in patients with cervical cancer. Furthermore, ectopic expression of miR-374b could significantly decrease cell proliferation and invasion ability. However, inhibition of miR-374b had opposite effects. Dual luciferase reporter assay, qRT-PCR, and Western blot analysis revealed that miR-374b overexpression suppressed cell proliferation and invasion ability via affecting FOXM1 expression. CONCLUSIONS: These results indicated that miR-374b acted as tumor suppressor and may serve as a potential target for cervical cancer treatment.

Isolation, identification, and degradation performance of a PFOA-degrading strain.

The perfluorooctanoic acid (PFOA)-degrading strain YAB1 was isolated from the soil near a perfluorinated compound production plant through acclimation and enrichment culture, using PFOA as the sole carbon source. This strain was preliminarily identified as Pseudomonas parafulva based on colony morphology, physiological and biochemical features, and 16S rRNA gene sequencing. Using shaking flask fermentation, the maximum tolerable concentration of YAB1 on PFOA was found to be 1000 mg/L. The optimal conditions for bacterial growth and PFOA degradation were 30°C, pH 7, 2% inoculum, and an initial PFOA concentration of 500 mg/L. After 96 h of culture, the PFOA degradation rate determined by GC-MS analysis was 32.4%. When 1 g/L glucose was added to the inorganic salt culture medium, the degradation rate increased to 48.1%. Glucose was the best exogenous carbon source for the degradation of PFOA. This study reports the degradation performance of PFOA-degrading bacteria.

[High cell density culture of phosphotransacetylase mutants of Escherichia coli BL21(DE3)].

Cell culture, organic acid production and foreign protein (TNF) expression of E. coli BL21(DE3) and its pta mutant were investigated. Under shaking conditions, TNF expression in pta mutant increased by 23%. During the fed-batch culture without limitation of specific growth rates, the mutant reached a cell density as high as 32.5 g(DCW)/L and total TNF expression at 2.8 g/L, while the parental strain only obtained 19.5 g(DCW)/L and 0.84 g/L. The results indicate that utility of pta mutant as a host is advantageous in foreign protein expression and high cell density culture. Meanwhile, the analysis data of organic acids accumulated during fed-batch culture showed that as the decrease of acetate production(42% of the parental strain), the accumulation of other organic acids(mainly pyruvate, lactate and succinate) obviously increased. As a result, the amount of total organic acids increased by 123% over its parent. The lactate production may be the main obstacle in further growth of the cells.

[Studies on bioconversion conditions and stereoselectivity of Arthrobacter K1108 hydantoinase].

The bioconversion conditions of hydantoinase of Arthrobacter K1108 were studied. It was shown that the optimum temperature of the enzyme is 55 degrees C, and the optimum pH is 7.0. The enzyme can be activated by Co2+ and Fe2+, while inhibited by Ca2+. The optimal substrate of the hydantoinase is 5-benzylhydantoin, while 5-phenylhydantoin and 5-indolylmethylhydantoin cannot effectively digested, showing a high specificity on the substrates. An investigation on the hydantoinase stereoselectivity mechanism showed that the N-carbamoylamino acid hydrolase is stereoselective but the hydantoin hydrolase is not.