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Rhizoctonia solani is a widespread and devastating plant pathogenic fungus that infects many important crops. This pathogen causes tobacco target spot, a disease that is widespread in many tobacco-growing countries and is destructive to tobacco. To identify antagonistic microorganisms with biocontrol potential against this disease, we isolated Streptomyces strains from forest inter-root soil and screened a promising biocontrol strain, ZZ-21. Based on in vitro antagonism assays, ZZ-21 showed a significant inhibitory effect on R. solani and various other phytopathogens. ZZ-21 was identified as Streptomyces olivoreticuli by its phenotypic, genetic, physiological and biochemical properties. Complete genome sequencing revealed that ZZ-21 harbored numerous antimicrobial biosynthesis gene clusters. ZZ-21 significantly reduced the lesion length in detached inoculated leaf assays and reduced the disease index under greenhouse and field conditions. Based on an in vitro antagonistic assay of ZZ-21 culture, the strain exhibited an antifungal activity against R. solani in a dose-dependent manner. The culture filtrate could impair membrane integrity, possibly through membrane lipid peroxidation. ZZ-21 could secrete multiple extracellular enzymes and siderophores. According to a series of antifungal assays, the extracellular metabolites of ZZ-21 contained antimicrobial bioactive compounds composed of proteins/peptides extracted using ammonium sulfate precipitation, which were stable under stress caused by high temperature and protease K. The EC 50 value for ammonium sulfate precipitation was determined to be 21.11 μg/mL in this study. Moreover, the proteins/peptides also exhibited biocontrol ability and were observed to alter the plasma membrane integrity of R. solani which were evaluated by biocontrol efficacy assays on detached tobacco leaves and PI staining. Overall, strain ZZ-21 shows the potential to be developed into a biopesticide against tobacco target spot disease. [Display omitted] • A Streptomyces strain ZZ-21 showed a significant inhibition effect on R. solani was isolated. • ZZ-21 was identified as Streptomyces olivoreticuli by phenotypic, genetic, physiological and biochemical properties. • The antimicrobial bioactive compounds was stable proteins/peptides. • ZZ-21 could impair membrane integrity of the pathogen fungus R. solani. [ABSTRACT FROM AUTHOR]

[Display omitted] • A new method for energy storage ejection is proposed using superelastic SMA wire. • A novel concept of correlating energy and SMA resistance change rate is proposed. • Ejection energy density and energy conversion efficiency are investigated by test. • Theoretical prediction model for ejection energy density of SMA wire is developed. Superelastic shape memory alloy (SMA) wire is a memorable deformation material with large resilience and high energy density. In this paper, a revolutionary and yet explainable property of the SMA is investigated and confirmed: superelastic SMA energy storage and release can be quantitatively measured using electrical resistance. This finding boosted the SMA with significant advantages and potential in the field of mechanical energy storage and ejection release. A state-of-the-art energy storage ejection device is designed to test the relationship among SMA wires' stress, strain, and electrical resistance. The resistance change rate, ejection energy density and energy conversion efficiency are studied in the SMA wire energy tests. The experimental results confirm that the resistance change rate of the superelastic SMA wire has a stable linear relationship with the strain. The ejection energy density increases with the resistance change rate. A theoretical model of the relationship between the ejection energy density and resistance change rate is established based on the experimental results. In conclusion, the superelastic SMA wire can achieve sophisticated tasks that require 'programmable' and predictable energy storage or ejection. [ABSTRACT FROM AUTHOR]

Abstract: Bullous pemphigoid (BP) is a cutaneous autoimmune inflammatory disease associated with subepidermal blistering and autoantibodies against BP180, a transmembrane collagen and major component of the hemidesmosome. Numerous inflammatory cells infiltrate the upper dermis in BP. IgG autoantibodies in BP fix complement and target multiple BP180 epitopes that are highly clustered within a non-collagen linker domain, termed NC16A. Anti-BP180 antibodies induce BP in mice. In this study, we generated a humanized mouse strain, in which the murine BP180NC14A is replaced with the homologous human BP180NC16A epitope cluster region. We show that the humanized NC16A (NC16A+/+) mice injected with anti-BP180NC16A autoantibodies develop BP-like subepidermal blisters. The F(ab′)2 fragments of pathogenic IgG fail to activate the complement cascade and are no longer pathogenic. The NC16A+/+ mice pretreated with mast cell activation blocker or depleted of complement or neutrophils become resistant to BP. These findings suggest that the humoral response in BP critically depends on innate immune system players. [Copyright &y& Elsevier]

Abstract: The present study investigated the role of integrin-linked kinase (ILK) in TGFβ1-stimulated invasion/migration of human ovarian cancer cells. We investigated TGFβ1 regulation of ILK, and effects of ILK knockdown on TGFβ1-stimulated invasion/migration and the associated proteinase systems, urokinase plasminogen activator (uPA) and matrix metalloproteinases (MMPs) in SKOV3 cells. TGFβ1 stimulated ILK kinase activity, and had no effect on ILK protein/mRNA levels. Transient transfection of an ILK-specific siRNA (ILK-H) reduced ILK protein level, mRNA level and kinase activity. ILK knockdown by ILK-H suppressed the basal and TGFβ1-stimulated invasion and migration. Further, ILK-H reduced the basal and TGFβ1-stimulated secretion of uPA, and increased the secretion of its inhibitor (PAI-1). Conversely, ILK-H did not affect TGFβ1-stimulated secretion of MMP2 and its cell-associated activator MT1-MMP. Additionally, TGFβ1 activated Smad2 phosphorylation, and this was not affected by ILK knockdown. Earlier reports indicate that Smad2 activation increased the expression of MMP2 and MT1-MMP. Thus, TGFβ1 may act through ILK-independent and Smad2-dependent signaling in regulating MMP2 and MT1-MMP in SKOV3 cells. Collectively, this study suggests that ILK serves as a key mediator in TGFβ1 regulation of uPA/PAI-1 system critical for the invasiveness of human ovarian cancer cells. And ILK is a potential target for cancer therapy. [Copyright &y& Elsevier]

Stromal-derived factor-1α (SDF-1α) is a chemokine signaling molecule that binds to the transmembrane receptor CXC chemokine receptor-4 (CXCR4) and carries out important functions in development tissue homeostasis. SDF-1α signaling via CXCR4 regulates the recruitment of stem and precursor cells to support tissue-specific repair or regeneration. In this study, we examined the contribution of SDF-1α signaling to the odontogenic differentiation of stem cells from the apical papilla (SCAP) induced by bone morphogenic protein 2 (BMP-2). CXCR4 expression was detected in cultured SCAP and SDF-1α promoted the migration of SCAP in Transwell assays. Blocking SDF-1α signaling by treatment with siRNA significantly affected BMP-2-induced mineralized nodule formation and alkaline phosphatase (ALP) activity. Moreover, blocking SDF-1α signaling inhibited the BMP-2-induced early expression of runt-related factor-2 (Runx-2) and strongly suppressed the induction of dentin matrix protein 1 (DMP-1) and dentin sialophosphoprotein (DSPP) expression by BMP-2. Furthermore, the interaction between SDF-1α and BMP-2 signaling was mediated via intracellular Smads and Erk activation. In conclusion, our results demonstrated that SDF-1α can significantly promote the migration of SCAP. Moreover, we revealed corequirement of the SDF-1α/CXCR4 signaling pathways in the BMP-2-induced odontogenic differentiation of SCAP, and these findings may be applied in new strategies for dental pulp regeneration. • A novel regulatory role of SDF-1α/CXCR4 in BMP-2 induced odontogenic differentiation. • Interaction between SDF-1α and BMP-2 signaling is mediated via Smad and Erk activation. • A promising therapeutic strategy for dentin-pulp engineering for future endodontic treatment. [ABSTRACT FROM AUTHOR]

[Display omitted] • A phase transition detection method is proposed for self-sensing and robustness. • Excitation signal is optimized for the thermal cycle pretreatment of SMA wire. • Thermal equilibrium points and end points of phase transition are distinguished. • A detection algorithm is developed based upon filtering and outlier processing. • A resistance-displacement regression model is built for displacement estimation. Shape memory alloy (SMA) wires are widely used as actuators because of their simplicity, high energy ratio, and Joule heat activation. The resistance behavior caused by the phase transition can predict the stress or strain of the SMA wire, which is called self-sensing. At present, there are researches on detecting the start and end points of phase transition based on resistance. However, the anti-interference ability of these researches is poor, and it is difficult to identify the thermal equilibrium points. Therefore, this paper proposes a novel resistance-based phase transition detection method with good robustness and displacement estimation. Firstly, the excitation signal is optimized for the thermal cycle pretreatment of the SMA wire. Secondly, the interferences of the resistance signal are determined, which are noise, small current signals, and step signals. Finally, using filtering and outlier processing, a phase transition region detection algorithm based on the difference of resistance extreme values is proposed. Moreover, a resistance-displacement model is established through linear regression. The experimental results show that the proposed method effectively resists the interference of signals and has good robustness. The mean relative error between the estimated and measured displacements is 4.43%. The resistance-displacement model effectively estimates the displacement of the SMA wire actuator and distinguishes the thermal equilibrium points and the end points of the phase transition. The proposed method can be used potentially for real-time phase transition detection, overheating protection, power consumption reduction, and self-sensing drive of sensorless actuators. [ABSTRACT FROM AUTHOR]

Fibroblast activation protein alpha (FAP) is a cell-surface expressed type II glycoprotein that has a unique proteolytic activity. FAP has active soluble forms that retain the extracellular portion but lack the transmembrane domain and cytoplasmic tail. FAP expression is normally very low in adult tissue but is highly expressed by activated fibroblasts in sites of tissue remodelling. Thus, FAP is a potential biomarker and pharmacological target in liver fibrosis, atherosclerosis, cardiac fibrosis, arthritis and cancer. Understanding the biological significance of FAP by investigating protein structure, interactions and activities requires reliable methods for the production and purification of abundant pure and stable protein. We describe an improved production and purification protocol for His 6 -tagged recombinant soluble human FAP. A modified baculovirus expression construct was generated using the pFastBac1 vector and the gp67 secretion signal to produce abundant active soluble recombinant human FAP (residues 27–760) in insect cells. The FAP purification protocol employed ammonium sulphate precipitation, ion exchange chromatography, immobilised metal affinity chromatography and ultrafiltration. High purity was achieved, as judged by gel electrophoresis and specific activity. The purified 82 kDa FAP protein was specifically inhibited by a FAP selective inhibitor, ARI-3099, and was inhibited by zinc with an IC 50 of 25 μM. Our approach could be adopted for producing the soluble portions of other type II transmembrane glycoproteins to study their structure and function. • A highly productive baculovirus expression construct was established for soluble human fibroblast activation protein alpha. • A specific purification protocol was established. • The soluble recombinant protein showed high purity and high specific enzyme activity. • The purified protease was inhibited by zinc at physiological concentrations. [ABSTRACT FROM AUTHOR]