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In order to screen novel fungicide leads, 19 pyrrolidine-2,4-dione derivatives containing the pharmacophores of both hydrazine and diphenyl ether were designed, synthesized, and characterized by FT-IR, 1H NMR, 13C NMR, and HR-MS. The obtained target compounds were evaluated for their antifungal activity against Rhizoctonia solani (Rs), Botrytis cinerea (Bc), and Fusarium graminearum (Fg). The bioassay results indicated that the majority of the target compounds exhibited striking biological activities against the above-mentioned fungi. Strikingly, target compound 4h obviously inhibited the growth of Rs in vitro with an EC50 value of 0.39 μg mL−1, which was better than the commercialized fungicide boscalid (2.21 μg mL−1). Subsequently, 4h was further evaluated for the in vivo anti-Rs effect on rice leaves, affording a control efficiency of 45.33% at 200 μg mL−1. Scanning electron microscopy (SEM) was used for observing the changes in the mycelium morphology. Numerous abnormal branches and swellings were found on the hyphae that were treated with 4h. Based on the bioassay results against Rs, a comparative molecular similarity index analysis model was formulated to further analyze the quantitative structure–activity relationship (QSAR) of the target compounds. The above 3D-QSAR analyses revealed that introducing hydrophobic 4-FPh, 4-ClPh, or 4-BrPh fragments at the R2 position could considerably increase the antifungal activity against Rs. [ABSTRACT FROM AUTHOR]

[Display omitted] • A mitochondria-targeted fluorescence probe for sensing ClO− was developed. • The probe exhibits superior selectivity for ClO− over other ROS. • The probe showed a fast response for sensing ClO− (<10 s). • The probe can be used for detecting exogenous and endogenous ClO− in mitochondria of living cells. The level of HClO/ClO− in mitochondria is essential to keep the normal function of mitochondria. Therefore, it is meaningful to accurately and quickly monitor ClO− in mitochondria. In this work, a new triphenylamine-based fluorescence probe PDTPA was designed and synthesized, in which pyridinium salt and dicyano-vinyl group were introduced as mitochondria targeting site and reaction site for ClO−. The probe showed high sensitivity and fast fluorescence response (<10 s) in the detection of ClO−. Moreover, the probe PDTPA had good linearity in a wide concentration range of ClO− and its detection limit was calculated as 10.5 μM. Confocal fluorescence images demonstrated that the probe could target mitochondria and track the fluctuations of endogenous/exogenous ClO− levels in the mitochondria of living cells. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • GdPO 4 /chitosan porous scaffolds was fabricated for bone regeneration. • 3D macropores in the scaffolds promoted bone tissue in-growth. • Gd3+ ions were controllably released from the GdPO 4 /chitosan scaffolds. • GdPO 4 nanoparticles significantly activated Smad/Runx2 signaling pathway. • GdPO 4 /chitosan porous scaffolds have a great application for bone tissue engineering. Abstract Gadolinium (Gd) is one of trace rare earth elements (REEs) existing in human bones; however, the underlying mechanisms of Gd element on positive cell response and bone regeneration have rarely been reported. Herein, we firstly constructed GdPO 4 /chitosan (CTS) scaffolds by lyophilisation method. The appropriate macropores and biocompatible chemical components improved the osteoconductivity of the GdPO 4 /CTS scaffolds, resulting in admired cell spreading and in vivo bone tissue in-growth. The concentrations of the as-released Gd3+ ions were kept in safety ranges, and had non-toxicity to rat bone marrow mesenchymal stem cells (rBMSCs). Notably, the GdPO 4 nanoparticles in the GdPO 4 /CTS scaffolds significantly promoted the osteogenic differentiation of rBMSCs via activated Smad/Runx2 signaling pathway. As compared with β-TCP/CTS scaffolds, the GdPO 4 /CTS scaffolds remarkably up-regulated the levels of ALP, Runx-2, OCN and Col-I expression. Moreover, rat critical calvarial defect models revealed that the newly formed bone tissues were much greater in the GdPO 4 /CTS group than in the β-TCP/CTS group. The exciting finding revealed the underlying mechanism of GdPO 4 nanoparticles on enhanced osteogenic activity, and provided a promising GdPO 4 -based scaffold for bone regeneration. [ABSTRACT FROM AUTHOR]

Simultaneous identification of vehicle load and structural damage is an issue of practical significance in structural health monitoring and maintenance of in-service concrete bridges. However, most methods proposed in history to deal with this engineering issue are solely based on data from a single source of structural vibration response measurement, which are subjected to problems such as incomplete understanding of the structural health, the computational inefficiency and the easy failure of the monitoring system. To this end, this paper proposes a new method of synthesizing data generated from two different types of sensors (the strain gauges and the accelerometers) to simultaneously identify the vehicle load and the structural damage which is established on the theories of weigh-in-motion method based on the strain influence line. The new method, which is supposed to be able to well solve the problems with the traditional approaches disseminated to the profession, is formulated in a flowchart for use, and applied to the actual Renyihe Bridge (a concrete rigid-frame continuous highway bridge with spans of 80m + 4 × 145m + 80m) to validate its effectiveness. The results suggest that the new method is of high accuracy in use in low vehicle speed scenarios and superior to the traditional simultaneous identification approach based on unitary structural acceleration sensing. [ABSTRACT FROM AUTHOR]

A new fluorescent emitter based on π-extended benzothiadiazole was synthesized. The emitter exhibited a large molar extinction coefficient, a high quantum yield of 98% and a large radiative decay rate of 108 s−1. Moreover, the obtained TADF-sensitized fluorescent OLED displayed excellent device performance with a high EQEmax of 14.3%. [ABSTRACT FROM AUTHOR]

[Display omitted] • A fluorescent probe was synthesized based on benzopyran-chromone for detection of ONOO−. • The probe shows short response time for ONOO− (<30 s). • The probe shows specifically selectivity and a very low detection limit of 22.4 nM for ONOO−. • The probe can accurately identify endogenous and exogenous ONOO− in HeLa cells. Peroxynitrite is widely present in organisms and closely related to many pathophysiological functions. Therefore, it is of great physiological significance to develop capable probes for detecting ONOO−. In this work, a novel fluorescent probe B-Ch was designed based on the intramolecular charge transfer (ICT) effect. By means of molecular engineering, the replacement from diethylamine group to hydroxyl group has improved the detection sensitivity of the probe. After the addition of ONOO−, the solution color and fluorescence showed noticeable changes, which were visible to the naked eye. The probe showed excellent advantages: visualization, good selectivity, low sensitivity (22.4 nM), good stability and biocompatibility, exogenous and endogenous imaging of ONOO− in HeLa cells. [ABSTRACT FROM AUTHOR]

Background. Total flavonoids of Rhododendron (TFR) is extracted from Rhododendron, a herbal medicine widely used in China. The main components are flavone compounds such as warfarin, rutin, quercetin, and hyperoside. We investigated the role of TRPV4 channel in the TFR induced endothelium-dependent hyperpolarizing factor- (EDHF-) mediated responses against ischemia/reperfusion injury (IR) in cerebral IR (CIR) rats. Methods. The morphological changes of cerebral cortex, the relaxation of cerebral basal artery (CBA), and cell membrane potential recording were studied in CIR rats. The outward potassium current in smooth muscle cell was recorded by whole-cell patch clamp recording. The protein expression of TRPV4, SKca, and IKca was determined. Confocal laser was used to measure the Ca2+ fluorescence intensity. Results. After treatment with TFR, the number of pyramidal cells in brain tissue increased and the number of empty or lightly stained cells decreased and these effects were eliminated by using HC-067047, Apamin, or TRAM-34. TFR induced and EDHF-mediated dilatation and hyperpolarization in CBA were also attenuated by using these inhibitors. The increased outward current density elicited by TFR in acutely isolated CBA smooth muscle cells was abolished by using TRAM-34 and Apamin. TFR upregulated the protein expression of TRPV4, SKca, and IKca that was also eliminated by these inhibitors. Laser scanning showed that the increased mean fluorescence intensity of Ca2+ by CIR was decreased by using TFR and that this effect was again eliminated by the above inhibitors. Conclusions. We conclude that in the CBA of the CIR rats the protective effect of TFR on ischemic cerebrovascular injury may be related to the activation of the TRPV4 in both endothelium and smooth muscle by increasing its expression and activity. The activation of TRPV4 channel in the endothelium may be linked to the opening of endothelial IKca/SKca channels that induces EDHF-mediated relaxation and hyperpolarization in the smooth muscle cell. In addition, the activation of TRPV4 in the smooth muscle cell in CBA may be linked with the activation of BKCa channel through a TRPV4-dependent pathway, reduce Ca2+ concentration in the cell, and relaxes the vessel. These findings may form a new therapeutic target for protection of ischemic brain injury and facilitate the use of Chinese medicine in brain protection. [ABSTRACT FROM AUTHOR]

[Display omitted] • A NIR fluorescence probe based on coumarin-cyanine hybrid was prepared for detection of ONOO−. • The probe showed high selectivity and sensitivity for ONOO− with low detection limit (41.88 nM). • This probe showed a ratio response to ONOO− with a large Stokes shift (239 nm). • The probe was capable of accurate imaging of ONOO− in mitochondria. There is an urgent need to develop highly sensitive and selective fluorescence probes for ONOO− in mitochondria. Herein, we reported a ratiometric fluorescent probe COUS with coumarin-cyanine hybrid as fluorophore and C = C bonds as reaction sites of ONOO−. The probe COUS was sensitive and selective to ONOO−, and had a large fluorescence emission shift (239 nm) as well as a low detection limit (41.88 nM). Moreover, COUS showed the mitochondrial targeting ability, and the targeting moiety could dissociate from the probe when reacting with ONOO−, which enabled COUS to accurately detect ONOO− in mitochondria. [ABSTRACT FROM AUTHOR]