Monoterpenoid signals and their transcriptional responses to feeding and juvenile hormone regulation in bark beetle Ips hauseri.

Hauser's engraver beetle, Ips hauseri, is a serious pest in spruce forest ecosystems in Central Asia. Its monoterpenoid signal production, transcriptome responses and potential regulatory mechanisms remain poorly understood. The quality and quantity of volatile metabolites in hindgut extracts of I. hauseri were found to differ between males and females and among three groups: beetles that were newly emerged, those with a topical application of juvenile hormone III (JHIII) and those that had been feeding for 24 h. Feeding males definitively dominated monoterpenoid signal production in I. hauseri, which uses (4S)-(-)-ipsenol and (S)-(-)-cis-verbenol to implement reproductive segregation from Ipstypographus and Ipsshangrila. Feeding stimulation induced higher expression of most genes related to the biosynthesis of (4S)-(-)-ipsenol than JHIII induction, and showed a male-specific mode in I. hauseri. JHIII stimulated males to produce large amounts of (-)-verbenone and also upregulated the expression of several CYP6 genes, to a greater extent in males than in females. The expression of genes involved in the metabolism of JHIII in females and males was also found to be upregulated. Our results indicate that a species-specific aggregation pheromone system for I. hauseri, consisting of (4S)-(-)-ipsenol and S-(-)-cis-verbenol, can be used to monitor population dynamics or mass trap killing. Our results also enable a better understanding of the bottom-up role of feeding behaviors in mediating population reproduction/aggregation and interspecific interactions.

Removing endotoxin from plasmid samples by Triton X-114 isothermal extraction.

Triton X-114 temperature transition extraction has been considered to be a simple and cost-effective strategy to eliminate endotoxin from plasmid preparations. However, a repeated cooling-heating process may promote the degradation of plasmid DNA. Based on the finding that the cloud point of Triton X-114 solution increases substantially in the presence of small amounts of sodium dodecyl sulfate (SDS) and that electrolytes decrease the cloud point of Triton X-114-SDS solution drastically, we designed a Triton X-114 isothermal extraction method for removing endotoxin from plasmid samples and found that it has the same endotoxin removal efficiency when compared with the temperature transition extraction method.

Evaluation of xenogeneic extracellular matrix fabricated from CuCl2-conditioned mesenchymal stem cell sheets as a bioactive wound dressing material.

The extracellular matrix has drawn considerable interest in tissue engineering not only acts as a bioactive three-dimensional scaffold but also regulates cell behaviors through providing biochemical signals. Extracellular matrix-based biomaterials, mainly derived from xenogeneic tissues, have shown positive outcomes in promoting cutaneous wound healing. However, such extracellular matrices only contain low doses of growth factors, which limit their therapeutic efficiency. Recent reports demonstrated that cell sheets made from mesenchymal stem cell can accelerate wound repair through enhanced re-epithelialization and angiogenesis, but its clinical translation is hindered by several limitations, such as the risk of aberrant immune responses and cost implications. In this study, acellular extracellular matrices were prepared from CuCl2-conditioned mesenchymal stem cell sheets and their in vivo wound healing properties were evaluated in a mouse model of full-thickness skin defect. We found that extracellular matrices derived from CuCl2-conditioned mesenchymal stem cell sheets have a compact surface with thick solid-like cross-sectional structure. Moreover, CuCl2 dramatically enriched the extracellular matrices with collagen I, collagen III, transforming growth factor-ß1, vascular endothelial growth factor, and basic fibroblast growth factor via hypoxia-inducible factor-1α activation. And as a consequence, the resulting extracellular matrices showed markedly improved in vivo wound healing potency through early adipocyte mobilization, enhanced granulation tissues formation, rapid re-epithelialization, and augmented angiogenesis. Therefore, we consider that the extracellular matrix derived from CuCl2-conditioned mesenchymal stem cell sheets has the potential for clinical translation and may lead to a novel strategy for wound management.

Growth Factor-Reinforced ECM Fabricated from Chemically Hypoxic MSC Sheet with Improved In Vivo Wound Repair Activity.

MSC treatment can promote cutaneous wound repair through multiple mechanisms, and paracrine mediators secreted by MSC are responsible for most of its therapeutic benefits. Recently, MSC sheet composed of live MSCs and their secreted ECMs was reported to promote wound healing; however, whether its ECM alone could accelerate wound closure remained unknown. In this study, Nc-ECM and Cc-ECM were prepared from nonconditioned and CoCl2-conditioned MSC sheets, respectively, and their wound healing properties were evaluated in a mouse model of full-thickness skin defect. Our results showed that Nc-ECM can significantly promote wound repair through early adipocyte recruitment, rapid reepithelialization, enhanced granulation tissue growth, and augmented angiogenesis. Moreover, conditioning of MSC sheet with CoCl2 dramatically enriched its ECM with collagen I, collagen III, TGF-ß1, VEGF, and bFGF via activation of HIF-1α and hence remarkably improved its ECM's in vivo wound healing potency. All the Cc-ECM-treated wounds completely healed on day 7, while Nc-ECM-treated wounds healed about 85.0% ± 8.6%, and no-treatment wounds only healed 69.8% ± 9.6% (p < 0.05). Therefore, we believe that such growth factor-reinforced ECM fabricated from chemically hypoxic MSC sheet has the potential for clinical translation and will lead to a MSC-derived, cost-effective, bankable biomaterial for wound management.