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The Src-homology 2 domain-containing phosphatase 2 (SHP2), which is encoded by PTPN11, participates in many cellular signaling pathways and is closely related to various tumorigenesis. Inhibition of the abnormal activity of SHP2 by small molecules is an important part of cancer treatment. Here, three abietane diterpenoids, named compounds 1–3, were isolated from Ajuga ovalifolia var. calantha. Spectroscopic analysis was used to identify the exact structure of the compounds. The enzymatic kinetic experiment and the cellular thermal shift assay showed compound 2 selectively inhibited SHP2 activity in vitro. Molecular docking indicated compound 2 targeted the SHP2 catalytic domain. The predicted pharmacokinetic properties by SwissADME revealed that compound 2 passed the majority of the parameters of common drug discovery rules. Compound 2 restrained A549 proliferation (IC50 = 8.68 ± 0.96 μM), invasion and caused A549 cell apoptosis by inhibiting the SHP2–ERK/AKT signaling pathway. Finally, compound 2 (Ajuforrestin A) is a potent and efficacious SHP2 inhibitor and may be a promising compound for human lung epithelial cancer treatment. [ABSTRACT FROM AUTHOR]

Purpose: On the background of innovation-driven growth strategy of the Chinese government, this study aims to explore the impact of the knowledge base on innovation-driven growth of a firm, which is moderated by organizational character. Design/methodology/approach: Based on the data of 965 Chinese listed companies, some hypotheses were tested using the method of hierarchical regression analysis. Findings: Organizational growth relies on both technological and business model innovations and their interactive effect. Knowledge base, both breadth and depth, makes a positive impact on the innovation-driven growth of an enterprise. In the impacting mechanism, an explicit organizational character not only has direct positive effects on business model innovation, it also strengthens the effect of knowledge breadth on business model innovation. On the contrary, an implicit organizational character is not significantly related to innovation. Research limitations/implications: In order to achieve growth, enterprises are suggested to adopt such dual innovation strategy, led by technological innovation and supplemented with business model innovation, which is supported by the integrated management of intangible resources, deep and broad knowledge, and explicit organizational character. Originality/value: A new theoretical framework of organizational innovation-driven growth was proposed. The realization paths of innovation-driven growth were explored. The idea of collaborative governance between the knowledge base and organizational character was raised. [ABSTRACT FROM AUTHOR]

Serine proteases play an important role in inflammation via PARs. However, little is known of expression levels of PARs on monocytes of allergic patients, and influence of serine proteases and PARs on TNF-α secretion from monocytes. Using quantitative real-time PCR (qPCR) and flowcytometry techniques, we observed that the expression level of PAR-2 in monocytes of patients with allergic rhinitis and asthma was increased by 42.9 and 38.2 %. It was found that trypsin, thrombin, and tryptase induced up to 200, 320, and 310 % increase in TNF-α release from monocytes at 16 h, respectively. PAR-1 agonist peptide, SFLLR-NH, and PAR-2 agonist peptide tc-LIGRLO-NH provoked up to 210 and 240 % increase in release of TNF-α. Since SCH 79797, a PAR-1 antagonist, and PD98059, an inhibitor of ERK inhibited thrombin- and SFLLR-NH-induced TNF-α release, the action of thrombin is most likely through a PAR-1- and ERK-mediated signaling mechanism. Similarly, because FSLLRN-NH, an inhibitor of PAR-2 diminished tryptase- and tc-LIGRLO-NH-induced TNF-α release, the action of tryptase appears PAR-2 dependent. Moreover, in vivo study showed that both recombinant cockroach major allergens Per a 1 and Per a 7 provoked upregulation of PAR-2 and PAR-1 expression on CD14+ cells in OVA-sensitized mouse peritoneum. In conclusion, increased expression of PAR-2 in monocytes of AR and asthma implicates that PAR-2 likely play a role in allergy. PAR-2- and PAR-1-mediated TNF-α release from monocytes suggests that these unique protease receptors are involved in the pathogenesis of inflammation. [ABSTRACT FROM AUTHOR]

Interleukin- (IL-) 18 and tryptase were previously reported to relate to asthma, but the correlation between these two potent proinflammatory molecules in asthma and their roles in mast cell accumulation remain uninvestigated. Using flow cytometric analysis technique and ovalbumin- (OVA-) sensitized mouse model, it was found that IL-18 and tryptase levels in the plasma of moderate and severe asthma were elevated, and they correlated well with each other. Tryptase and agonist peptides of protease activated receptor- (PAR-) 2 induced substantial quantity of IL-18 release. IL-18 and tryptase provoked mast cell accumulation in peritoneum of OVA-sensitized mice. OVA-sensitization increased number of IL-18 receptor (R)+ mast cells. IL-18 and tryptase induced dramatic increase in IL-18R+ mast cells and mean fluorescence intensity (MFI) of IL-18R on mast cells. Moreover, while IL-18 induced an increase in PAR-2+ mast cells in nonsensitized mice, IL-18 and tryptase provoked increases in IL-4 and thymic stromal lymphopoietin (TSLP) in the peritoneum of OVA-sensitized mice. In summary, the correlation between IL-18 and tryptase in plasma of patients with asthma indicates close interactions between them, which should be considered for development of anti-IL-18 and antitryptase therapies. Interactions between IL-18 and tryptase may contribute to mast cell recruitment in asthma. [ABSTRACT FROM AUTHOR]

Wall-jet/thin-layer amperometric electrochemical detection (ECD) coupled with high-performance liquid chromatography (HPLC) was used here for the simultaneous analysis of dopamine (DA) and homovanillic acid (HVA) at a glassy carbon electrode. Compared with the conventional thin-layer mode and wall-jet mode, the presented wall-jet/thin-layer ECD has the advantages of enhanced capture of electroactive DA and HVA on the working electrode to give enhanced responses and more convenient washing/refreshment of the working electrode surface. Under optimized conditions, the HPLC-ECD calibration curves show good linearity from 0.01 to 100 μM for DA and HVA, and the limits of detection (LODs) obtained were 1.1 nM for DA and 0.7 nM for HVA which are lower than those obtained with an UV-vis detector and a commercial electrochemical detector. The method was tested on human urine with satisfactory results. The balance of response-signal, signal-background and noise level for our HPLC-ECD system is also discussed. In addition, a demethylation electrooxidation mechanism for HVA is suggested through potentiostatic bulk electrolysis, electrospray ionization-mass spectrometry, fluorescent spectrophotometry and cyclic voltammetry studies. [ABSTRACT FROM AUTHOR]