Expression of sphingosine kinase 1 in amoeboid microglial cells in the corpus callosum of postnatal rats

Sphingosine kinase 1 (SphK1), a key enzyme responsible for phosphorylating sphingosine into sphingosine-1-phosphate (S1P) has been shown to be expressed in monocytes and monocyte-derived peripheral macrophages. This study demonstrates SphK1 immunoexpression in amoeboid microglial cells (AMC), a nascent monocyte-derived brain macrophage in the corpus callosum of developing rat brain. SphK1 immunofluorescence expression, which appeared to be weak in AMC in normal brain, was markedly induced by lipopolysaccharide (LPS) or hypoxia treatment. Western blot analysis also showed increased expression level of SphK1 in the corpus callosum rich in AMC after LPS treatment. Detection of SphK1 mRNA and its upregulation after LPS treatment was confirmed in primary culture AMC by RT-PCR. Administration of N, N-dimethylsphingosine (DMS), a specific inhibitor of SphK1, effectively reduced upregulated SphK1 immunoexpression in AMC both in vivo and in vitro. This was corroborated by western blot which showed a decrease in SphK1 protein level of callosal tissue with DMS pretreatment. Remarkably, LPS-induced upregulation of the transcription factor NFκB was suppressed by DMS. We conclude that SphK1 expression in AMC may be linked to regulation of proinflammatory cytokines via an NFκB signaling pathway

Ecological and navigational impact of the construction and operation of the Qingyuan dam

Dam construction has important impact on the ecological environment and navigation conditions of a river. Therefore, evaluating the degree of impact of such engineering constructions and seeking the optimum management are vital. This study considered the example of the construction of the Qingyuan Dam on the Beijiang River (China). The flow condition was calculated using a two-dimensional hydrodynamic model, and a habitat suitability model and navigation risk indicators were used to conduct quantitative assessment of the impact of different scenarios. The spawning ground habitat of Megalobrama terminalis was taken as an ecological measurement index. The gray correlation analysis method was used to quantify the influence of four flow indexes (i.e., water surface slope, backflow, flow velocity, and water depth) on navigation safety. The simulation results showed that construction of the Qingyuan Dam had serious negative impact on the ecological environment in the dry season, but that dry season navigation conditions have been improved greatly. Following construction of the dam, with increase in the Feilaixia Hydro-junction discharge, the ecological and navigable usable area both first increased and then decreased. With comprehensive consideration of the usable area and the spatial distributions of habitat suitability and navigation risk, when the Feilaixia Hydro-junction discharge is 3000 m3/s and the water level in front of the Qingyuan Dam is 10 m, the ecological and navigation benefits of the studied river reach were determined to be optimal. These research results could provide guidance for the management of the Feilaixia–Qingyuan river section, and help deliver optimum ecological and navigational benefits

The Comparison of Adipose Stem Cell and Placental Stem Cell in Secretion Characteristics and in Facial Antiaging

Background. Mesenchymal stem cells are the most commonly used seed cells in biomedical research and tissue engineering. Their secretory proteins have also been proven to play an important role in tissue healing. Methods. We isolated adipose stem cells and placental stem cells and performed analysis examining characteristics. The secretory proteins were extracted from conditioned medium and analyzed by MALDI-TOF/TOF. The antiaging effect of conditioned mediums was evaluated by the results of facial skin application. Results. Adipose stem cells and placental stem cells were found to be very similar in their surface markers and multipotency. The specific proteins secreted from adipose stem cells were more adept at cell adhesion, migration, wound healing, and tissue remodeling, while the proteins secreted by placental stem cells were more adept at angiogenesis, cell proliferation, differentiation, cell survival, immunomodulation, and collagen degradation. While these two types of conditioned medium could improve the facial index, the improvement of Melanin index after injection of the adipose stem cell conditioned medium was much more significant. Conclusion. The results suggest that the secreted proteins are ideal cell-free substances for regeneration medicine, especially in the antiaging field

Characterization of the Auxin Efflux Transporter PIN Proteins in Pear

PIN-FORMED (PIN) encodes a key auxin polar transport family that plays a crucial role in the outward transport of auxin and several growth and development processes, including dwarfing trees. We identified a dwarfing pear rootstock ‘OHF51’ (Pyrus communis), which limits the growth vigor of the ‘Xueqing’ (Pyrus bretschneideri × Pyrus pyrifolia) scion, and isolated 14 putative PbPINs from the pear Pyrus bretschneideri. The phylogenic relationships, structure, promoter regions, and expression patterns were analyzed. PbPINs were classified into two main groups based on the protein domain structure and categorized into three major groups using the neighbor-joining algorithm. Promoter analysis demonstrated that PbPINs might be closely related to plant growth and development. Through quantitative real-time PCR (qRT-PCR) analysis, we found that the expression patterns of 14 PbPINs varied upon exposure to different organs in dwarfing and vigorous stocks, ‘OHF51’ and ‘QN101’ (Pyrus betulifolia), indicating that they might play varying roles in different tissues and participated in the regulation of growth vigor. These results provide fundamental insights into the characteristics and evolution of the PINs family, as well as the possible relationship between dwarfing ability and auxin polar transport

Identification of avermectin-high-producing strains by high-throughput screening methods

Avermectins produced by Streptomyces avermitilis are potent against a broad spectrum of nematode and arthropod parasites with low-level side effects on the host organisms. This study was designed to investigate a high-throughput screening strategy for the efficient identification of avermectin high-yield strains. The production protocol was miniaturized in 96 deep-well microplates. UV absorbance at 245 nm was used to monitor avermectin production. A good correlation between fermentation results in both 96 deep-well microplates and conventional Erlenmeyer flasks was observed. With this protocol, the production of avermectins was determined in less than 10 min for a full plate without compromising accuracy. The high-yield strain selected through this protocol was also tested in 360 m(3) batch fermentation with 1.6-fold improved outcome. Thus, the development of this protocol is expected to accelerate the selection of superior avermectin-producing strains