Schistosoma egg antigens suppress LPS-induced inflammation in human IMR-90 cells by modulation of JAK/STAT1 signaling.

BACKGROUND: The regulation of the balance between inflammatory and anti-inflammatory events during the treatment of pulmonary infection is very important. Soluble Schistosoma egg antigens (SEA) can effectively inhibit the expression of cytokines during hepatic acute inflammation. However, the mechanisms by which these proteins suppress the inflammatory responses in lung cells remain unclear. The purpose of this study was to investigate the ability of SEA to inhibit pulmonary inflammation. METHODS: The effects of SEA were investigated in LPS-treated lung IMR-90 cells. The involvement of the JAK/STAT-1 signaling pathway in these effects was evaluated by employing CBA assays, quantitative polymerase chain reaction, and western blotting experiments. RESULTS: Pretreatment of IMR-90 cells with appropriate concentrations of SEA protected cells against the cytotoxic effects of LPS-induced inflammation in a time-dependent manner. SEA pretreatment significantly attenuated the LPS-induced activation of the JAK/STAT1 signaling pathway, including the upregulation of JAK1/2 and STAT1, as well as the production of inflammatory cytokines. The level of phosphorylated STAT1 gradually declined in response to increasing concentrations of SEA. Based on these findings, we hypothesize that SEA-induced anti-inflammatory effects initiate with the downregulation of the IFN-γ-JAK-STAT1 signaling pathway, resulting in the attenuation of LPS-induced inflammation in IMR-90 cells. CONCLUSION: Our study is the first to demonstrate the anti-inflammatory activity of SEA in an in vitro model of pulmonary inflammation, involving the modulation of JAK/STAT1 signaling. We propose SEA as potential therapeutic or preventive agents for the selective suppression of STAT1 and the control of inflammatory response in lung IMR-90 cells.

Study on the Shale Gas Reservoir-Forming Characteristics of the Taiyuan Formation in the Eastern Qinshui Basin, China.

Shales are widely developed in the strata of the Carboniferous-Permian coal measures in the Qinshui Basin, and these shales have great potential for shale gas exploration. In this paper, the shales of the Taiyuan Formation in the eastern Qinshui Basin are studied. The shales of the Taiyuan Formation in the study area are investigated through field investigation, organic geochemical testing, X-ray diffraction, scanning electron microscopy, high pressure mercury injection, low temperature liquid nitrogen adsorption and PetroMod simulation and through other tests to study the reservoir characteristics, such as organic geochemistry, mineralogy, petrology, pore permeability, and gas burial history. The results show that the shales of the Taiyuan Formation are well developed over the whole area with a thickness of more than 60 m. The average organic matter content is 2.95%, and the kerogen type is type III. The shale maturity (average value is 2.45%) corresponds to the stage of high maturity evolution, indicating that a large amount of shale gas has been generated in this area. A high content of quartz and clay minerals indicates a high fracturability. The nanopores in the shale reservoir are well developed at pore sizes between 2˜10 nm and greater than 1000 nm; however, the pores at the other pore sizes are poorly developed, resulting in weak pore connectivity in the reservoir. According to the results of the PetroMod simulation, the shale of the Taiyuan Formation has undergone two subsidence and two uplift processes. The Yanshanian magmatic intrusion is the key factor for the rapid increase in gas production. In addition, the geological structure of the area is relatively simple, and the burial history and caprock thickness are also the main controlling factors of gas generation and preservation. The shale-sandstone-shale combination and shale-coal-shale combination are the main models of shale gas preservation. This comprehensive study suggests that the shale gas of the Taiyuan Formation in the eastern Qinshui Bain has good potential for exploration and development.

Coverage evaluation of universal bacterial primers using the metagenomic datasets.

BACKGROUND: The coverage of universal primers for the bacterial 16S rRNA gene plays a crucial role in the correct understanding of microbial community structure. However, existing studies on primer coverage are limited by the lack of appropriate databases and are restricted to the domain level. Additionally, most studies do not account for the positional effect of single primer-template mismatches. In this study, we used 7 metagenomic datasets as well as the Ribosomal Database Project (RDP) to assess the coverage of 8 widely used bacterial primers. RESULTS: The coverage rates for bacterial primers were found to be overestimated by previous studies that only investigated the RDP because of PCR amplification bias in the sequence composition of the dataset. In the RDP, the non-coverage rates for all primers except 27F were ≪6%, while in the metagenomic datasets, most were ≫10%. If one considers that a single mismatch near the 3' end of the primer might greatly reduce PCR efficiency, then some phylum non-coverage rates would change by more than 20%. Primer binding-site sequence variants that could not pair with their corresponding primers are discussed. CONCLUSIONS: Our study revealed the potential bias introduced by the use of universal bacterial primers in the assessment of microbial communities. With the development of high-throughput, next-generation sequencing techniques, it will become feasible to sequence more of the hypervariable regions of the bacterial 16S rRNA gene. This, in turn, will lead to the more frequent use of the primers discussed here.