The influence mechanism of resource sharing on tourism industry innovation.

The development of the concept of "sharing" in the era of the digital economy has promoted significant changes in the innovation mechanism of the tourism industry. This article takes 31 provinces (municipalities and districts) in China as the research object, and collect four types of tourism statistics. Inspired by resource-based theory and dynamic capability theory, the article builds a research model of resource sharing for tourism industry innovation, proposes relevant hypotheses, discusses the influence mechanism of tourism industry innovation, and uses a fixed effects model and intermediary mechanism model for empirical test. The results show that the constructed model has good explanatory power and adaptability. Resource sharing can significantly drive tourism industry innovation, and the conclusion is robust. Tourism industry marketization, innovation ability, and competitiveness play an intermediary role in resource sharing to promote tourism industry innovation. The influence of resource sharing on tourism industry innovation has regional heterogeneity. The article aims to reveal the influence mechanism of resource sharing on tourism industry innovation under the digital economy, and the research conclusions can provide references for various provinces (municipalities and districts) to improve regional industrial innovation ability.

Shu-Di-Huang and Gan-Cao Herb Pair Restored the Differentiation Potentials of Mesenchymal Stem Progenitors in Treating Osteoporosis via Downregulation of NF-κB Signaling Pathway.

BACKGROUND: Shu-Di-Huang (Radix Rehmanniae Praeparata, RR) and Gan-Cao (liquorice, L) are frequently used traditional Chinese herb pair in treating osteoporosis (OP). However, the exact mechanism of the RR and L herb pair (RR-L) remains unclear. To explore the efficacy and possible mechanisms of RR-L in treating OP, in silico, in vitro, and in vivo experiments were conducted in the current study. METHODS: In silico, potential therapeutic target genes and active chemical compounds of RR-L herb pair were predicted and constructed into a network. In vivo, 30 Sprague Dawley rats were divided into 3 groups, including the sham group, the OP model group, and the RR-L-treated OP group. Micro-CT and pathological sections were conducted to validate the therapeutic effects of RR-L in treating OP. MSCs of rats were isolated and cultured in vitro to validate the mesenchymal stem cells (MSCs) related phenotype changes, including Alizarin red staining, Oil red staining, and immunofluorescence. In vitro, cell proliferation analysis, Alizarin red staining, Oil red staining, immunofluorescence of NF-κB, and protein expression of PPARγ, RUNX2, OCN, and p65 were conducted on MSCs to explore the RR-L containing serum in vitro. Also, activator and inhibitor of NF-κB signaling pathway were introduced to determine the possible mechanism of RR-L in the treatment of OP via enhancing MSCs proliferation and differentiation. RESULTS: In silico, 168 chemical compounds with a property of oral bioavailability ≥30% and drug-likeness ≥0.18 were recognized as potentially active compounds in RR-L and 249 genes were found to be the targets of which. Among them, 120 genes were found to be therapeutic genes of RR-L in treating OP and KEGG and GO analysis of which demonstrated that RR-L involves in lipid metabolism and multiple inflammation-related signaling pathways. In vivo, ovariectomy- (OVX-) induced OP phenotypes in Sprague Dawley rats include bone mineral density and microarchitecture damaging, abnormal bone metabolism, upregulation of inflammation markers, and damaged differentiation potential of MSCs. Treatment of RR-L reversed the trend and restored the differentiation potential of MSCs. In vitro, RR-L containing serum promoted the osteogenic differentiation and suppressed adipogenic differentiation of MSCs via downregulation of the NF-κB signaling pathway. Also, RR-L containing serum inhibited the tumor necrosis factor-α (TNF-α) induced activation of the NF-κB signaling pathway. On the opposite, the addition of the NF-κB specific inhibitor significantly reduced the effect of RR-L on MSCs. CONCLUSIONS: In the current study, network pharmacology prediction and experimental validation elucidated that the RR-L herb pair restored damaged MSC differentiation potential via the NF-κB signaling pathway; this could be the possible mechanism of RR-L in treating OP. This finding provides an alternative option in OP therapy.

Construction, immune protection and innate immune response of shuffled polyvalent ompAs vaccines.

Our previous studies demonstrated that molecular breeding via DNA shuffling directs the evolution of polyvalent vaccines with desired traits, which leads to generation of polyvalent ompA vaccines using Vibrio alginolyticus VA0764 primers. Here, we replaced VA0764 primers with Edwardsiella tarda ompA primers to generate new polyvalent ompA vaccines by DNA shuffling of the same five ompA genes from four species of bacteria E. tarda, V. parahaemolyticus, V. alginolyticus and Escherichia coli. We identified four polyvalent vaccine candidates from a eukaryotic expressing library EompAs-FE containing 82 ompAs using active immune protection against V. alginolyticus and E. tarda. Furthermore, we explored mechanisms of polyvalent vaccine candidates by investigation of the innate immune response to these ompAs, and found that expression of IL-1ß, IL-8, IL-15, COX-2, IFN-γ, TLR-1, TLR-3 and C3b genes was elevated as a characteristic feature of these polyvalent vaccine candidates. These results indicate that use of different primers to construct a DNA library selects new evolution of polyvalent vaccines with desired traits, and polyvalent ompA vaccines elicit high innate immune response.

Edwardsiella tarda Tunes Tricarboxylic Acid Cycle to Evade Complement-Mediated Killing.

Evasion of complement-mediated killing is a common phenotype for many different types of pathogens, but the mechanism is still poorly understood. Most of the clinic isolates of Edwardsiella tarda, an important pathogen infecting both of human and fish, are commonly found serum-resistant. To explore the potential mechanisms, we applied gas chromatography-mass spectrometry (GC-MS)-based metabolomics approaches to profile the metabolomes of E. tarda EIB202 in the presence or absence of serum stress. We found that tricarboxylic acid (TCA) cycle was greatly enhanced in the presence of serum. The quantitative real-time PCR (qRT-PCR) and enzyme activity assays validated this result. Furthermore, exogenous succinate that promotes the TCA cycle increased serum resistance, while TCA cycle inhibitors (bromopyruvate and propanedioic acid) that inhibit TCA cycle, attenuated serum resistance. Moreover, the enhanced TCA cycle increased membrane potential, thus decreased the formation of membrane attack complex at cell surface, resulting serum resistance. These evidences suggested a previously unknown membrane potential-dependent mechanism of serum resistance. Therefore, our findings reveal that pathogen mounts a metabolic trick to cope with the serum complement-mediated killing.