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The inhibition of root growth was investigated in wheat seedlings exposed to 3 mM zinc (Zn). Zn treatment with or without 250 µM 2-phenyl-4,4,5,5,-tetrame-thylimidazoline-3-oxide-1-oxyl (PTIO) or 10 µM diphenylene iodonium (DPI) significantly inhibited growth, increased malondialdehyde content and lowered cell viability in roots. The most prominent changes of these three parameters at Zn+DPI treatment could be partly blocked by high PTIO concentration (1 mM). The production of nitric oxide (NO) and hydrogen peroxide (H2O2) influenced each other under different treatments, with the highest NO level and the highest H2O2 accumulation in Zn+DPI-treated roots. Compared with Zn-stressed roots, catalase, soluble peroxidase (POD), ascorbate peroxidase and superoxide dismutase decreased in Zn+DPI-treated roots, suggesting that ROS generation from plasma membrane (PM) NADPH oxidase was associated with the regulation of antioxidant enzyme activities. Additionally, Zn-treated roots exhibited significant decreases in cell wall-bound POD, diamine oxidase and polyamine oxidase activities. Our results suggested that Zn-induced effects on root growth resulted from NO interaction with H2O2 and that Zn+DPI-induced strongest inhibition could be explained by the highest increase in the endogenous NO content and the reduction of extracellular ROS production. [ABSTRACT FROM AUTHOR]

Abstract: We present a fast method to detect humans from stationary surveillance videos. It is based on a cascade of LogitBoost classifiers which use covariance matrices as object descriptors. We have made several contributions. First, our method learns the correlation between appearance and foreground features and show that the human shape information contained in foreground observations can dramatically improve performance when used jointly with appearance cues. This contrasts with traditional approaches that exploit background subtraction as an attentive filter, by applying still image detectors only on foreground regions. As a second contribution, we show that using the covariance matrices of feature subsets rather than of the full set in boosting provides similar or better performance while significantly reducing the computation load. The last contribution is a simple image rectification scheme that removes the slant of people in images when dealing with wide angle cameras, allowing for the appropriate use of integral images. Extensive experiments on a large video set show that our approach performs much better than the attentive filter paradigm while processing 5–20 frames/s. The efficiency of our subset approach with state-of-the-art results is also demonstrated on the INRIA human (static image) database. [Copyright &y& Elsevier]

Acrolein (ACR) is a metabolic byproduct in vivo and a ubiquitous environmental toxicant. It is implicated in the initiation and development of many diseases through multiple mechanisms, including the induction of oxidative stress. Currently, our understanding of the body defense mechanism against ACR toxicity is still limited. Given that hydrogen sulfide (H 2 S) has strong antioxidative actions and it shares several properties of ACR scavenger glutathione (GSH), we, therefore, tested whether H 2 S could be involved in ACR detoxification. Taking advantage of two cell lines that produced different levels of endogenous H 2 S, we found that the severity of ACR toxicity was reversely correlated with H 2 S-producing ability. In further support of the role of H 2 S, supplementing cells with exogenous H 2 S increased cell resistance to ACR, whereas inhibition of endogenous H 2 S sensitized cells to ACR. In vivo experiments showed that inhibition of endogenous H 2 S with CSE inhibitor markedly increased mouse susceptibility to the toxicity of cyclophosphamide and ACR, as evidenced by the increased mortality and worsened organ injury. Further analysis revealed that H 2 S directly reacted with ACR. It promoted ACR clearance and prevented ACR-initiated protein carbonylation. Collectively, this study characterized H 2 S as a presently unrecognized endogenous scavenger of ACR and suggested that H 2 S can be exploited to prevent and treat ACR-associated diseases. [Display omitted] • Acrolein (ACR) is a toxicant implicated in the development of many diseases. • H2S shares many properties of ACR scavenger GSH. • The level of H2S governed cell and mouse fate to ACR toxicity. • H2S abolished ACR-initiated protein carbonyl formation. • H2S reacted with ACR, leading to ACR clearance. [ABSTRACT FROM AUTHOR]

Abstract: A hierarchical shadow detection algorithm for color aerial images is presented in this paper to meet two challenges for static shadow detection in the literature: different brightness and illumination conditions in different images and the complexity of aerial images. The hierarchical algorithm consists of two levels of processing: the pixel level classification, achieved through modelling an image as a reliable graph (RG) and maximizing the graph reliability using the EM algorithm, and the region level verification, achieved through minimizing the Bayesian error by further exploiting the domain knowledge. Further analyses show that MRF model based segmentation is a special case of the RG model. The relationship between the RG model and the relaxation labeling model is also discussed. A quantitative comparison between this method and a state-of-the-art shadow detection algorithm clearly indicates that this method is promising for delivering effective shadow detection performance under different illumination and brightness conditions. [Copyright &y& Elsevier]

Abstract: In reporter assays for detection of dioxins, the dioxin-responsive element (DRE) is generally used as a sensor sequence. In several systems, the CYP1A1 promoter containing DREs (DREcyp) is inserted into a part of the long terminal repeat of mouse mammary tumor virus (LTRMMTV) to improve sensitivity of assays. We found that DREcyp-LTRMMTV responds not only to dioxins and dioxin-like compounds but also to forskolin, a cAMP-elevating agent. This effect was dose-dependent and reproduced by other cAMP-elevating agents including 8-bromo-cAMP and 3-isobutyl-methylxanthine. The cAMP response element (CRE) and CRE-like sequences were absent in DREcyp-LTRMMTV and not involved in this process. In contrast to the effect of dioxin, the activation of DREcyp-LTRMMTV by cAMP was independent of the aryl hydrocarbon receptor (AhR), a ligand-dependent transcription factor for DRE. Furthermore, neither DREcyp, LTRMMTV nor the consensus sequence of DRE alone was activated in response to cAMP. These data elucidated for the first time that the combination of DREcyp with LTRMMTV causes a peculiar response to cAMP and suggested that use of AhR antagonists is essential to exclude false-positive responses of DREcyp-LTRMMTV-based bioassays for detection and quantification of dioxins and dioxin-like compounds. [Copyright &y& Elsevier]

In order to efficiently utilize the agricultural by-products, apricot kernel skins (AKS) and reduce the resource waste, the AKS was added to partially replace the wheat flour to develop the healthy bread in our preliminary study. In this paper, the effects of AKS addition and ultrasound irradiation on the quality properties of bread were investigated by the texture analyzer, confocal laser scanning microscope, electronic nose, tongue and gas chromatography-ion mobility spectrometry (GC-IMS), respectively. The results indicate that the addition of AKS had the negative effects on the microstructure of dough and the texture of fresh bread, but the ultrasonic treatment on the dough could significantly reduce the negative effects. Furthermore, AKS addition slowed the deterioration of the bread texture during chilled storage, and enriched the varieties of volatile organic compounds (VOCs) of bread. In a word, AKS could be employed in novel bread development so as to reduce the resource waste and environmental pollution. • AKS addition influenced the microstructure of dough and the texture of fresh bread. • The ultrasonic treatment on the dough could reduce the negative effects of AKS. • AKS slowed the deterioration of the bread texture during chilled storage. • AKS enriched the varieties of volatile organic compounds of bread. • Potential applications of AKS and ultrasound were identified. [ABSTRACT FROM AUTHOR]

3D object recognition is a fundamental task in 3D computer vision. View-based methods have received considerable attention due to their high efficiency and superior performance. To better capture the long-range dependencies among multi-view images, Transformer has recently been introduced into view-based 3D object recognition and achieved excellent performance. However, the information among views on multiple scales is not utilized sufficiently in the existing Transformer-based methods. To address this limitation, we proposed a 3D object recognition method named iMVS to i ntegrate M ulti- V iew information on multiple S cales. Specifically, for the single-view image/features at each scale, we adopt a hybrid feature extraction module consisting of CNN and Transformer to jointly capture local and non-local information. For the extracted multi-view image features at each scale, we develop a feature transfer module including a view Transformer block to achieve the information transfer across views. Following a sequential process of the single-view feature extraction and multi-view feature transfer on multiple scales, the multi-view information is sufficiently interacted. Subsequently, the multi-scale features with multi-view information are fed into our designed feature aggregation module to generate a category-specific descriptor, where the adopted channel Transformer block facilitates the descriptor to be more expressive. Coupling with these designs, our method can fully exploit the information embedded within multi-view images. Experimental results on ModelNet40, ModelNet10 and a real-world dataset MVP-N demonstrate the superior performance of our method. • The view-based 3D object recognition method makes full use of multi-view information • The transfer module achieves multi-view feature interaction on multiple scales • The channel Transformer-based module effectively aggregates multi-scale features • Experimental results demonstrate the effectiveness of our method iMVS [ABSTRACT FROM AUTHOR]

Hydrogen peroxide (H2O2) induces apoptosis of mesangial cells via c-Jun N-terminal kinase (JNK)-activator protein-1 (AP-1) and extracellular signal-regulated kinase (ERK)-AP-1 pathways. We recently found that subtoxic doses of proteasome inhibitors, MG132 and lactacystin, dramatically enhanced H2O2-induced apoptosis in mesangial cells. In this report, we examined molecular mechanisms involved in this phenomenon, especially focusing on AP-1 pathways. Reporter assays showed that MG132 induced activation of AP-1. However, pharmacological inhibitors of AP-1, retinoic acid, and curcumin, did not suppress the proapoptotic effect of MG132. Suppression of JNK–AP-1 by transfection with either a dominant-negative mutant of JNK or a dominant-negative mutant of c-Jun did not attenuate the apoptosis enhancement by MG132. Similarly, suppression of ERK–AP-1 by PD98059 or dominant-negative mutants of ERK did not affect the apoptosis-promoting effect of MG132. Interestingly, pretreatment with MG132 did not enhance activation of AP-1 by H2O2. These data suggested a novel, AP-1-independent promotion of apoptosis by proteasome inhibitors. [Copyright &y& Elsevier]

This paper investigates the generation of large field-of-view (FOV) and high-resolution (HR) panorama images for smartphones. Existing techniques like image stitching struggle to produce satisfactory results due to geometry misalignment and inconsistent appearance. To circumvent the inherent challenges of image stitching methods and generate high-quality panoramas, we treat the image stitching problem as a multiple-reference-based super-resolution problem. Specifically, one large-FOV low-resolution (LR) image and several overlapped small-FOV HR images are taken as inputs, where the LR image acts as a base and multi-view references provide rich HR information. Building on this foundation, a novel multi-view references image super-resolution framework (MVRefSR) is proposed. Within this framework, to address the residual geometric misalignment between the LR-Ref image pairs after coarse alignment, a flow-based RefSR network (FlowSRNet) is proposed, which super-resolves LR patches with corresponding HR references. To facilitate adaptive feature fusion and minimize distortion in structured regions, a fusion weight estimation module and a gradient branch are introduced in FlowSRNet. Finally, the large-FOV HR image is generated by combining these SR patches together. Furthermore, the lack of real-world RefSR datasets for smartphones is addressed by designing an innovative dataset construction pipeline. Extensive experiments demonstrate the superior performance of FlowSRNet and MVRefSR over the compared SR methods and image stitching software, which proves the effectiveness of generating panoramas from a new perspective. • A novel multi-view references image super-resolution framework (MVRefSR) is proposed to generate the large field-of-view and high-resolution panoramas from a new perspective. • Two modules, a fusion weight estimation module and a gradient branch, are adopted to enhance the performance of our reference-based super-resolution (RefSR) methods within our MVRefSR framework. • A new RefSR dataset generation pipeline and a real-world RefSR dataset are presented to address the lack of datasets and facilitate the study of real-world RefSR. • Experimental results demonstrate the superiority of our RefSR network and our framework MVRefSR, which proves the effectiveness of generating panoramas from a new perspective. [ABSTRACT FROM AUTHOR]

Cytidine/uridine monophosphate kinase 2 (CMPK2) is known as a nucleoside monophosphate kinase in mitochondria to maintains intracellular UTP/CTP, and could be induced by immunostimulants LPS and Poly (I:C) in mammals, suggesting its potential antiviral and antibacterial role. In this study, CMPK2 was cloned and characterized in Fathead minnow (FHM) cells. In vivo analysis of tissue distribution revealed that CMPK2 transcript was detected in all the tissues of zebrafish (Danio rerio) examined in this study, particularly abundant in liver, spleen and kidney. In addition, indirect immunofluorescence showed that CMPK2 was localized in the cytoplasm of FHM cells. Expression of CMPK2 mRNA was significantly up-regulated following challenge with Spring viraemia of carp virus (SVCV), poly(I:C), or zebrafish IFN1 and IFN3 both in vitro and in vivo. Furthermore, overexpression and RNA interference of CMPK2 in SVCV-infected FHM cells showed significantly antiviral effect. In summary, this study for the first time shows the presence and distribution of CMPK2 in different tissues of zebrafish, but also demonstrates its antiviral potential against SVCV infection in vivo. These new findings could contribute to explain the molecular mechanism of the CMPK2 mediated antiviral function. • CMPK2 was cloned and characterized in Fathead minnow (FHM) cells. • CMPK2 was identified as an Interferon Stimulated Gene in fish for the first time. • Overexpression and RNA inference of CMPK2 in SVCV-infected FHM cells showed significantly antiviral effect. [ABSTRACT FROM AUTHOR]

Abstract microRNA (miR)-141-3p has context-dependent effects on tumor progression. In this study, we attempted to explore the expression and function of miR-141-3p in cervical cancer. We found that miR-141-3p expression was significantly increased in cervical cancer specimens relative to normal cervical tissues. Moreover, miR-141-3p levels were associated with tumor size and lymph node metastasis status. Ectopic expression of miR-141-3p significantly increased cervical cancer cell proliferation, colony formation, invasion, and epithelial to mesenchymal transition, whereas depletion of miR-141-3p suppressed cervical cancer cell proliferation and invasion. FOXA2 was identified to be a target of miR-141-3p. Overexpression of miR-141-3p led to a marked inhibition of endogenous FOXA2 in cervical cancer cells. FOXA2 silencing phenocopied the effects of miR-141-3p overexpression on cervical cancer cell proliferation and invasion. Enforced expression of FOXA2 blocked the effects of miR-141-3p on cervical cancer cell proliferation and invasion. miR-141-3p overexpression significantly accelerated the growth of xenograft tumors, which was accompanied by a striking reduction in FOXA2 expression. miR-141-3p acts as an oncogene in cervical cancer largely through repression of FOXA2. Targeting miR-141-3p may represent a potential therapeutic strategy for cervical cancer. Highlights • miR-141-3p acts as an oncogene in cervical cancer. • miR-141-3p targets FOXA2 in cervical cancer. • FOXA2 silencing phenocopies the effects of miR-141-3p overexpression on cervical cancer cells. [ABSTRACT FROM AUTHOR]

With the rapid development of three-dimensional (3D) vision technology and the increasing application of 3D objects, there is an urgent need for 3D object recognition in the fields of computer vision, virtual reality, and artificial intelligence robots. The view-based method projects 3D objects into two-dimensional (2D) images from different viewpoints and applies convolutional neural networks (CNN) to model the projected views. Although these methods have achieved excellent recognition performance, there is not sufficient information interaction between the features of different views in these methods. Inspired by the recent success achieved by vision transformer (ViT) in image recognition, we propose a hybrid network by taking advantage of CNN to extract multi-scale local information of each view, and of transformer to capture the relevance of multi-scale information between different views. To verify the effectiveness of our multi-view convolutional vision transformer (MVCVT), we conduct experiments on two public benchmarks, ModelNet40 and ModelNet10, and compare with those of some state-of-the-art methods. The final results show that MVCVT has competitive performance in 3D object recognition. • Proposing a new architecture for view-based 3D object recognition. • Combining the respective advantages of convolutional neural network and transformer. • Designing a multi-scale feature fusion module. • Designing a masking mechanism to reflect spatial relationships between views. [ABSTRACT FROM AUTHOR]

Hydrogen sulfide (H 2 S), an endogenous gas mediator with multifaced biological functions, has been shown to be effective in the prevention and treatment of renal sclerosis in several models of chronic renal diseases. The mechanisms involved are still unclear. Given that Ang II- and TGF-β-induced renal tubular epithelial-mesenchymal transition (EMT) is a pivotal cellular event leading to renal sclerosis, we examined whether and how H 2 S intervened the processes of EMT. Ang II stimulated EMT in renal tubular epithelial cells, as indicated by the increased level of α-smooth muscle actin and a decreased level of E-cadherin. This effect of Ang II was blocked by a TGF-β receptor kinase inhibitor, indicative of a mediating role of TGF-β. Consistently, Ang II stimulated TGF-β activation and addition of the exogenous TGF-β1 also induced EMT. In the presence of H 2 S donor NaHS, the EMT-promoting actions of Ang II and TGF-β1 were abolished, which was associated with a reduced TGF-β activity. Further analysis using a human recombinant active TGF-β1 revealed that H 2 S cleaved the disulfide bond in the dimeric active TGF-β1 and promoted the formation of inactive TGF-β1 monomer. Collectively, these results indicate that H 2 S counteracted Ang II- and TGF-β1-induced EMT through mechanisms involving direct inactivation of TGF-β1. Our study thus provides novel mechanistic insight into the anti-fibrotic actions of H 2 S and suggest that H 2 S could be used to treat renal sclerotic diseases. [ABSTRACT FROM AUTHOR]

Abstract: Surface-enhanced Raman scattering (SERS)-active substrates of polyvinyl alcohol/gold–silver (PVA/Au–Ag) nanofibers were prepared using a simple approach involving electrospinning. The tunable surface plasmon resonance (SPR) of gold–silver alloy (Au–Ag alloy) nanoparticles (NPs) was achieved by controlling the feed ratio between gold and silver precursors. A higher concentration of Au–Ag alloy NPs could be obtained than the conventional methods, using 1wt% of PVA as the stabilizer. The Au–Ag alloy structure was demonstrated by HRTEM and STEM-EDX. After the electrospinning, the Au–Ag alloy NPs were successfully embedded in PVA nanofibers, as shown in the SEM and TEM images. Raman spectra displayed an apparent enhancement in the signal of 4-mercaptobenzoic acid (4-MBA), pyridine, and thiophenol molecules pre-absorbed from their ethanol solution onto the PVA/Au–Ag nanofibers. Different SERS effects were achieved by varying the Au content or excitation wavelength. [Copyright &y& Elsevier]

Abstract: A facile approach was developed to prepare novel multifunctional Fe2O3/Au/Ag nanostructures integrated with isolated functions involving magnetic and optical properties. The Fe2O3/Au/Ag hybrid nanoparticles with different thicknesses of Ag shell were prepared by adjusting the amount of the AgNO3. Surface structures were varied from the rough with pinhole to smooth and pinhole free surfaces with increasing amounts of AgNO3. The surface plasmon resonance was tuned in a very wide region from that of Au to Ag. Surface enhanced Raman scattering (SERS) effects were also investigated, employing thiophenol (TP) and aminothiophenol (PATP) as probe molecules. It was revealed that the SERS intensity was strongly depended on the molar ratio of Ag and Au. With an increase in the Ag molar fractions, SERS signals were enhanced to the maximum due to the surface plasmon resonance of the pinhole structure. The magnetic enrichment for on line SERS monitoring the molecules with low concentration was performed based on the magnetic core and the SERS activity of the bimetallic shells. This enrichment procedure improved efficiently the limits of the SERS detection. It was shown that the multicomponent nanoparticles have potential applications in the fields of optical devices and magnetic separation. [Copyright &y& Elsevier]

Abstract: Subtilase cytotoxin (SubAB) is the prototype of a distinct AB5 toxin family produced by Shiga toxigenic Escherichia coli. Recent reports disclosed pro-apoptotic pathways triggered by SubAB, whereas its anti-apoptotic signals have not been elucidated. In the present study, we investigated pro-survival signaling elicited by SubAB, especially focusing on extracellular signal-regulated kinase (ERK) and Akt. We found that SubAB activated ERK and Akt, and inhibition of individual kinases enhanced SubAB-triggered apoptosis. SubAB induced endoplasmic reticulum (ER) stress, and other ER stress inducers mimicked the stimulatory effects of SubAB on ERK and Akt. Attenuation of ER stress reduced SubAB-induced phosphorylation of these kinases, suggesting involvement of the unfolded protein response (UPR). SubAB induced activation of protein kinase-like ER kinase (PERK) and phosphorylation of eukaryotic translation initiation factor 2α (eIF2α), and phosphorylation of eIF2α by salubrinal caused activation of ERK and Akt, leading to cell survival. Dominant-negative inhibition of PERK enhanced SubAB-induced apoptosis and reduced phosphorylation of ERK and Akt. Furthermore, the anti-apoptotic effect of eIF2α was significantly reversed by inhibition of ERK and Akt. These results suggest cytoprotective roles of ERK and Akt in SubAB-triggered, ER stress-mediated apoptosis. [Copyright &y& Elsevier]

Abstract: We recently reported that subtilase cytotoxin (SubAB) has the potential to attenuate experimental models of inflammatory diseases . Currently, little is known about underlying mechanisms involved in this therapeutic effect. In the present report, we show that SubAB induces A20, the endogenous negative regulator of NF-κB, in vitro and in vivo. This stimulatory effect occurred at the transcriptional level, and SubAB induced activation of the A20 promoter. We found that, in the early phase, SubAB triggered activation of NF-κB in a dose-dependent manner. Blockade of NF-κB abrogated expression of A20 by SubAB. SubAB rapidly triggered the unfolded protein response (UPR), and induction of the UPR by other agents (thapsigargin and A23187) mimicked the stimulatory effects of SubAB, both on NF-κB and on A20. The induction of A20 by thapsigargin was correlated with activation of the A20 promoter, which was not observed in the κB-mutated A20 promoter. Furthermore, induction of A20 by SubAB was substantially attenuated by treatment with different chemical chaperones. These results elucidated for the first time that the anti-inflammatory SubAB has the potential to induce A20 through the UPR–NF-κB-dependent pathway. [Copyright &y& Elsevier]

[Display omitted] • A true sense of global smoothing approach for compact linear toolpath is presented. • Computational efficient geometric and motion smoothing methods are included. • The geometric smoothing generates global smoothed path without unwanted undulation. • The motion smoothing yields jerk-limited feed-axis trajectories by FIR filtering. The toolpaths for curved surfaces generated by most existing computer-aided-manufacturing applications are always consisted by short line segments. Due to the first-order discontinuity of the short line segment toolpath, the precise following of them must result in frequent acceleration/decelerations, which is easy to excite structural vibration of the machine tools, thus degrading the machining quality. To solve this problem, local corner rounding approaches are widely researched, however, most areas on the toolpath after corner rounding remains linear segments, unlike the global smoothing method who replaces all short line segments to spline curves thus obtaining smoother feed motion. Compared with the local corner rounding method, the global smoothing always requires iterative computes to satisfy the accuracy requirement, which makes it so time consuming that can hardly be utilized in CNC systems. To deal with above problem, this paper proposes a highly stable global smoothing method which does not need iterative computations. This is realized by a control-point-assigning-based global geometric smoothing algorithm and a FIR (Finite Impulse Response) filtering-based global motion smoothing algorithm. During global geometric smoothing, the short line segment toolpath is replaced by piecewise B-spline curve segments whose control points are directly assigned under the error tolerance constraint. During the global motion smoothing, a fast spline interpolation method based on FIR filtering is provided to generate smooth axial position references of the piecewise B-spline curve segments under the axial drive constraint. The whole global smoothing approach does not require pre-processing or iterative computation, which makes it easy to be applied. Extensive illustrations including numerical tests and experimental verification/comparison tests demonstrate the favorable effects of the proposed method in real-time capability and motion smoothing performance. Comparing with typical local corner rounding approach, the proposed global smoothing approach results in shorter motion time and better smoothness. Comparing with typical existing global smoothing method, the proposed method performs better in no required pre-processing and high-order motion smoothness. [ABSTRACT FROM AUTHOR]

Abstract: Geranylgeranylacetone (GGA), an anti-ulcer agent, has anti-inflammatory potential against experimental colitis and ischemia-induced renal inflammation. However, molecular mechanisms involved in its anti-inflammatory effects are largely unknown. We found that, in glomerular mesangial cells, GGA blocked activation of nuclear factor-κB and consequent induction of monocyte chemoattractant protein 1 (MCP-1) by inflammatory cytokines. It was inversely correlated with induction of unfolded protein response (UPR) evidenced by expression of 78kDa glucose-regulated protein (GRP78) and suppression of endoplasmic reticulum stress-responsive alkaline phosphatase. Various inducers of UPR including tunicamycin, thapsigargin, A23187, 2-deoxyglucose, dithiothreitol, and AB5 subtilase cytotoxin reproduced the suppressive effects of GGA. Furthermore, attenuation of UPR by stable transfection with GRP78 diminished the anti-inflammatory effects of GGA. These results disclosed a novel, UPR-dependent mechanism underlying the anti-inflammatory potential of GGA. [Copyright &y& Elsevier]

Abstract: Preadipocytes constitutively express GATA-2 and GATA-3 that are required to halt the cells at the undifferentiated stage. However, we unexpectedly found that K-7174, a GATA-specific inhibitor, did not induce but rather inhibited differentiation of 3T3-L1 preadipocytes. It was associated with lack of lipid accumulation, blunted expression of adipocyte markers including adiponectin and peroxisome proliferator-activated receptor γ (PPARγ), and sustained expression of a preadipocyte marker monocyte chemoattractant protein 1 (MCP-1). Subsequent experiments revealed that K-7174 had the potential to induce endoplasmic reticulum (ER) stress evidenced by induction of GRP78 and CHOP. Other inducers of ER stress completely reproduced the effects of K-7174 including suppression of lipid accumulation, blockade of induction of adiponection and PPARγ and maintenance of MCP-1 expression. These results indicated a possibility that ER stress suppresses adipocyte differentiation and that GATA inhibitor K-7174 has the potential for interfering with adipogenesis through induction of ER stress. [Copyright &y& Elsevier]

Abstract: K-7174, a GATA-specific inhibitor, is a putative anti-inflammatory agent that attenuates effects of inflammatory cytokines in certain cell types. However, molecular mechanisms involved have not been elucidated. We found that, in glomerular podocytes, induction of monocyte chemoattractant protein 1 (MCP-1) and inducible nitric oxide synthase (iNOS) by TNF-α was abrogated by K-7174. It was correlated with unexpected induction of unfolded protein response (UPR) evidenced by: (1) induction of endogenous indicators 78kDa glucose-regulated protein and CCAAT/enhancer-binding protein–homologous protein, and (2) suppression of an exogenous indicator, endoplasmic reticulum stress-repressive alkaline phosphatase. In podocytes, induction of UPR by either tunicamycin, thapsigargin, A23187 or AB5 subtilase cytotoxin completely reproduced the suppressive effect of K-7174. Furthermore, K-7174-elicited UPR abrogated induction of MCP-1 and iNOS not only by TNF-α but also by medium conditioned by activated macrophages. These results suggested a novel, UPR-dependent mechanism underlying the anti-inflammatory potential of K-7174. [Copyright &y& Elsevier]

Abstract: In the current study, we attempted to develop a method for bioassay-based screening of microorganisms that degrade dioxin. However, a crucial problem encountered was that the standard dioxin 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) added to bacterial medium immediately disappeared from the liquid phase due to its adsorption onto polypropylene (PP) tubes. Among other aromatic hydrocarbons, adsorption onto PP tubes was also observed in β-naphthoflavone but not in benzo[a]pyrene. Adsorption of TCDD was observed not only onto PP tubes but also onto polystyrene, glass, and PP tubes with low affinity for DNA or protein. Silanization was not effective at preventing adsorption of TCDD. TCDD immobilized onto PP tubes was recovered by organic solvents, including ethanol, methanol, and dimethyl sulfoxide (DMSO). The elution efficiency of the immobilized TCDD by DMSO was approximately 85%. Based on these findings, screening of bacteria that degrade dioxin was attempted as follows. First, TCDD was immobilized onto PP tubes. Second, bacterial suspension was added to the tubes and incubated for biodegradation of TCDD. Third, remaining, immobilized TCDD was eluted by DMSO and subjected to a reporter bioassay to evaluate the level of TCDD. Using this method, we demonstrated successful screening of bacteria that have the potential for degradation of dioxin. [Copyright &y& Elsevier]

Abstract: Secreted alkaline phosphatase (SEAP) and Metridia luciferase (MLuc) are useful reporter molecules in vitro, but little is understood about their usefulness in vivo. In this study, we investigated in vivo activity of recombinant SEAP and MLuc in blood and urine. When SEAP-transfected cells or recombinant SEAP were injected into rats, substantial increase in the level of serum SEAP was observed. In contrast, activity of SEAP was not detected in urine of rats injected with either the SEAP-transfected cells or recombinant SEAP. SEAP activity was also undetectable in urine of SEAP-injected Nagase analbuminemic rats in which glomerular permeability to macromolecules is enhanced. When MLuc-transfected cells were implanted into rats, activity of MLuc was undetectable not only in urine but also in serum. Even immediately after intravenous injection of recombinant MLuc, activity of MLuc was not detected in serum. Subsequent experiments revealed that, in contrast to SEAP, MLuc was rapidly inactivated either by rat serum, fetal bovine serum, or human serum. Albumin was identified as the molecule responsible for the inhibition of MLuc activity. These data elucidated advantages and limitations of secreted reporter molecules SEAP and MLuc under in vivo situations. [Copyright &y& Elsevier]

In this article, we describe a highly sensitive biosensing system, DRESSA, for detection of dioxin and dioxin-like chemicals. Tandem copies of the dioxin-responsive element (DRE) fused to a minimal viral promoter were subcloned into an expression plasmid upstream of a secreted alkaline phosphatase (SEAP) gene. When murine hepatoma cell line Hepa-1c1c7 was stably transfected with this construct, established sensor clones secreted SEAP following stimulation with 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). A clone HeDS49 was found to be extremely sensitive; it secreted SEAP in response to TCDD in dose- and time-dependent manners, and the minimal detection limit was 100fM. To detect more than 6pM of TCDD, the whole assay time (from cell seeding to measurement of SEAP activity) could be reduced to 4h. Secretion of SEAP was induced selectively by other activators of DRE (3-methylcholanthrene, benzo[a]pyrene, and β-naphthoflavone) but not by activators of unrelated responsive elements. These data suggested that because of the rapidity, easiness, specificity, and high sensitivity of DRESSA, it is more suitable than currently available detection systems for dioxin and dioxin-like chemicals and would be of great advantage to high-throughput screening of these pollutants in environmental samples. [Copyright &y& Elsevier]

Nek2A is a cell-cycle-regulated protein kinase that localizes to the centrosome and kinetochore. Our recent studies provide a link between Nek2A and spindle checkpoint signaling [J. Biol. Chem. 279 (2004) 20049]. Extracellular signal-regulated kinase 2 (Erk2) is an important kinase, which belongs to mitogen activating protein (MAP) kinase family. Here we demonstrated that Nek2A binds specifically to Erk2. Erk2 interacts with Nek2A via a conserved Erk2 docking site located to the C-terminus of Nek2A. Our studies indicate this docking site is essential and sufficient for a direct Nek2A-Erk2 interaction. In addition, our immunocytochemical studies show that Nek2A and Erk2 are co-localized to centrosome. Significantly, elimination of Nek2A by RNA interference delocalized Erk2 from its centrosomal location, while inhibition of Erk2 kinase activity did not affect the localization of Nek2A in centrosome. We propose that Erk2 links extracellular signaling to centrosome dynamics by Nek2A. [Copyright &y& Elsevier]

A novel photochromic nanocomposite film containing polyoxotungstoeuropate K12[EuP5W30O110] entrapped in polyvinylpyrrolidone has been prepared through a spin-on coating technique. Thus-obtained amorphous nanocomposite film was characterized by IR spectra, UV–vis absorption spectra, XRD, SEM, TG-DTA, and ESR. Results show that polyoxotungstoeuropate interacts with polyvinylpyrrolidone strongly and disperses homogeneously in the matrix. The composite film exhibits good photochromic properties. When irradiated with UV light, the transparent film changes from colorless to blue. Then, bleaching occurs when the film is in contact with ambient air or O2 in the dark. The photochromism of the composite film is due to charge transfer by reduction of polyoxotungstoeuropate and oxidation of polyvinylpyrrolidone. [Copyright &y& Elsevier]

Novel photochromic nanocomposite thin film containing phosphotungstic acid entrapped in polyacrylamide was prepared using ultrasound technique. TEM image revealed that the polyoxometalates nanoparticles with narrow size distribution were finely dispersed in polymer matrix. IR spectra showed that the Keggin geometry of polyoxometalates was still preserved inside the composite film and strong Coulombic interaction was built between heteropolyoxometalates and polyacrylamide via hydrogen bond. It was found that the thermal stability of the hybrid film was lower than that of pure polymer but the film was stable enough for photochromic application from the TG–DTA curves. The transparent film changed from colorless to blue under UV irradiation and showed reversible photochromism. The bleaching process occurred when the film was in contact with air or O2 in the dark. The photoreduced process was in accordance with radical mechanism. [Copyright &y& Elsevier]

A novel thermochromic sol–gel film has been prepared for the first time through entrapping phosphomolybdic acid into a kind of inorganic–organic matrix co-hydrolyzed from tetraethylorthosilicate and 3-aminopropyltriethoxysilane. The thus-obtained amorphous nanocomposite film was characterized by IR spectra, UV–vis absorption spectra, XRD, TG–DTA, and ESR. Results show that phosphomolybdate polyanions interact with R–NH+3 cations strongly and disperse homogeneously in the sol-gel matrix. The sol–gel film exhibits thermochromic properties. Annealed from 120 to 180°C, the transparent film changes from pale-yellow to blue. A possible charge-transfer process has been suggested to explain the thermochromism. [Copyright &y& Elsevier]