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Find video protocols related to scientific articles indexed in Pubmed.
Chemosensitization of solid tumors by inhibition of Bcl-xL expression using DNAzyme.
Oncotarget
PUBLISHED: 10-27-2014
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DNAzymes are a novel class of gene suppressors that selectively bind to an RNA substrate by Watson-Crick base pairing and cleave phosphodiester bonds. To explore the potential for therapeutic use of catalytic DNA molecules, active DNAzymes targeting the bcl-xL gene were generated through a multiplex in vitro selection. The DNAzyme-mediated down-regulation of the bcl-xL expression was demonstrated in various cancer cell lines by Western blots. Treatment of the cells with the active DNAzyme led to increases in percentage of apoptotic cells and cytochrome c release from mitochondria, a hall marker of apoptosis. When combined with chemotherapeutics such as Taxol, the DNAzyme significantly sensitised a panel of cancer cells to apoptosis as measured by cell survival assay. In Taxol-resistant cells, down-regulation of bcl-xL expression by the DNAzyme reversed the chemo-resistant phenotype of the cancer cells. In a xenograft mouse model, the DNAzyme was delivered into the tumors via an ALZET osmotic pump and shown to chemosensitize PC3 tumor when treating with Taxol. The results from the present study demonstrate that bcl-xL DNAzyme treatment facilitates apoptosis in solid tumors and suggest the potential use of bcl-xL DNAzyme in combination with chemotherapeutics for cancer therapy.
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[Clinical analysis of 108 cases of jaw ameloblastoma].
Shanghai Kou Qiang Yi Xue
PUBLISHED: 10-24-2014
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To review the age of onset, gender, sites, pathologic types, operation methods and prognosis, and explore the internal relations in 108 cases of ameloblastoma.
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Elevated expression of HMGA1 correlates with the malignant status and prognosis of non-small cell lung cancer.
Tumour Biol.
PUBLISHED: 09-18-2014
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High-mobility group A1 (HMGA1) has been suggested to play a significant role in tumor progression, but little is known about the accurate significance of HMGA1 in non-small cell lung cancer (NSCLC) patients. The aim of this study was to identify the role of HMGA1 in NSCLC. The expression status of HMGA1 was observed initially in NSCLC by Gene Expression Omnibus (GEO). The expression of HMGA1 messenger RNA (mRNA) and protein was examined in NSCLC and adjacent normal lung tissues through real-time PCR and immunohistochemistry. Meanwhile, the relationship of HMGA1 expression levels with clinical features and prognosis of NSCLC patients was analyzed. In our results, HMGA1 was overexpressed in NSCLC tissues compared with adjacent normal lung tissues in microarray data (GSE19804). HMGA1 mRNA and protein expressions were markedly higher in NSCLC tissues than in normal lung tissues (P?
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[Central nervous system infection caused by Exophiala dermatitidis in a case and literature review].
Zhonghua Er Ke Za Zhi
PUBLISHED: 09-17-2014
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To summarize the clinical features, imaging characteristics, diagnosis and treatment of a case with central nervous system infection caused by Exophiala dermatitidis, as well as to review the related literature.
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Nutrient transformation during aerobic composting of pig manure with biochar prepared at different temperatures.
Environ Technol
PUBLISHED: 09-12-2014
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The effects of the corn stalk charred biomass (CB) prepared at different pyrolysis temperatures as additives on nutrient transformation during aerobic composting of pig manure were investigated. The results showed that the addition of CB carbonized at different temperatures to pig manure compost significantly influenced the compost temperature, moisture, pH, electrical conductivity, organic matter degradation, total nitrogen, [Formula: see text] and NH3 variations during composting. Compared with control and adding CB charred at lower temperature treatments, the addition of CB prepared over 700°C resulted in higher pH (over 9.2) and NH3 emission and lower potherb mustard seed germination index value during the thermophilic phase. Peak temperatures of composts appeared at 7 days for control and 11 days for CB added treatments. During 90 days composting, the organic matter degradation could be increased over 14.8-29.6% after adding of CB in the compost mixture. The introduction of CB in pig manure could prolong the thermophilic phase, inhibit moisture reduce, facilitate the organic matter decomposition, reduce diethylene triamine pentaacetic acid (DTPA) extractable Zn and Cu contents in pig manure composts and increase ryegrass growth. The study indicated that the corn stalk CB prepared around 500°C was a suitable additive in pig manure composting.
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Ground-state proton transfer kinetics in green fluorescent protein.
Biochemistry
PUBLISHED: 09-11-2014
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Proton transfer plays an important role in the optical properties of green fluorescent protein (GFP). While much is known about excited-state proton transfer reactions (ESPT) in GFP occurring on ultrafast time scales, comparatively little is understood about the factors governing the rates and pathways of ground-state proton transfer. We have utilized a specific isotopic labeling strategy in combination with one-dimensional (13)C nuclear magnetic resonance (NMR) spectroscopy to install and monitor a (13)C directly adjacent to the GFP chromophore ionization site. The chemical shift of this probe is highly sensitive to the protonation state of the chromophore, and the resulting spectra reflect the thermodynamics and kinetics of the proton transfer in the NMR line shapes. This information is complemented by time-resolved NMR, fluorescence correlation spectroscopy, and steady-state absorbance and fluorescence measurements to provide a picture of chromophore ionization reactions spanning a wide time domain. Our findings indicate that proton transfer in GFP is described well by a two-site model in which the chromophore is energetically coupled to a secondary site, likely the terminal proton acceptor of ESPT, Glu222. Additionally, experiments on a selection of GFP circular permutants suggest an important role played by the structural dynamics of the seventh ?-strand in gating proton transfer from bulk solution to the buried chromophore.
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The relationship between the plant-encoded RNA-dependent RNA polymerase 1 and alternative oxidase in tomato basal defense against Tobacco mosaic virus.
Planta
PUBLISHED: 09-05-2014
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Salicylic acid (SA) plays a critical role in plant defense against pathogen attack. The SA-induced viral defense in plants is distinct from the pathways mediating bacterial and fungal defense, which is pathogenesis-related protein-independent but involves an RNA-dependent RNA polymerase 1 (RDR1)-mediated RNA silencing mechanism and/or an alternative oxidase (AOX)-associated defense pathway. However, the relationship between these two viral defense-related pathways remains unclear. In this study, Tobacco mosaic virus (TMV) inoculation onto Solanum lycopersicum (tomato) leaves induced a rapid induction of the SlAOX1a transcript level as well as the total and CN-resistant respiration at 0.5 dpi, followed by an increase in SlRDR1 gene expression at 1 dpi in the upper uninoculated leaves. Silencing SlRDR1 using virus-induced gene silencing system significantly reduced SlRDR1 expression and tomato defense against TMV but had no evident effect on SlAOX1a transcription. Conversely, silencing SlAOX1a not only effectively reduced the AOX1a transcript level, but also blocked the TMV-induced SlRDR1 expression and decreased the basal defense against TMV. Furthermore, the application of an exogenous AOX activator on empty vector-silenced control plants greatly induced the accumulation of SlRDR1 and SlAOX1a transcript and reduced TMV viral RNA accumulation, but failed to have such effects on SlRDR1-silenced plants. Moreover, RDR1-overexpressed transgenic Nicotiana benthamiana plants enhanced defense against TMV than the empty vector-transformed plants, but these effects were not affected by the exogenous AOX activator or inhibitor. These results indicate that RDR1 is involved in the AOX-mediated defense pathway against TMV infection and plays a crucial role in enhancing RNA silencing to limit virus systemic spread.
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[Analyses of segment motor function in patients with degenerative lumbar disease on the treatment of WavefleX dynamic stabilization system].
Zhonghua Yi Xue Za Zhi
PUBLISHED: 08-27-2014
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To explore the changes of range-of-motion (ROM) in patients with degenerative lumbar disease on the treatment of WavefleX dynamic stabilization system and examine the postoperative lumbar regularity and tendency of ROM.
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MSEA: detection and quantification of mutation hotspots through mutation set enrichment analysis.
Genome Biol.
PUBLISHED: 08-21-2014
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Many cancer genes form mutation hotspots that disrupt their functional domains or active sites, leading to gain- or loss-of-function. We propose a mutation set enrichment analysis (MSEA) implemented by two novel methods, MSEA-clust and MSEA-domain, to predict cancer genes based on mutation hotspot patterns. MSEA methods are evaluated by both simulated and real cancer data. We find approximately 51% of the eligible known cancer genes form detectable mutation hotspots. Application of MSEA in eight cancers reveals a total of 82 genes with mutation hotspots, including well-studied cancer genes, known cancer genes re-found in new cancer types, and novel cancer genes.
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Heterogeneous DNA methylation contributes to tumorigenesis through inducing the loss of coexpression connectivity in colorectal cancer.
Genes Chromosomes Cancer
PUBLISHED: 07-31-2014
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Increasing evidence indicates the high heterogeneity of cancer cells. Recent studies have revealed distinct subtypes of DNA methylation in colorectal cancer (CRC); however, the mechanism of heterogeneous methylation remains poorly understood. Gene expression is a natural, intermediate quantitative trait that bridges genotypic and phenotypic features. In this work, we studied the role of heterogeneous DNA methylation in tumorigenesis via gene expression analyses. Specifically, we integrated methylation and expression data in normal and tumor tissues, and examined the perturbations in coexpression patterns. We found that the heterogeneity of methylation leads to significant loss of coexpression connectivity in CRC; this finding was validated in an independent cohort. Functional analyses showed that the lost coexpression partners participate in important cancer-related pathways/networks, such as ErbB and mitogen-activated protein kinase (MAPK) signaling pathways. Our analyses suggest that the loss of coexpression connectivity induced by methylation heterogeneity might play an important role in CRC. To our knowledge, this is the first study to interpret methylation heterogeneity in cancer from the perspective of coexpression perturbation. Our results provide new perspectives in tumor biology and may facilitate the identification of potential biomedical therapies for cancer treatment. © 2014 Wiley Periodicals, Inc.
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Structure and gene cluster of the O antigen of Escherichia coli L-19, a candidate for a new O-serogroup.
Microbiology (Reading, Engl.)
PUBLISHED: 07-24-2014
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Escherichia coli L-19 isolated from a healthy individual did not agglutinate with any of 21 polyvalent antisera that cover 174 E. coli O-serogroups. The strain was studied in respect to the O-antigen (O-specific polysaccharide, OPS) structure and genetics. The LPS was isolated by phenol-water extraction of bacterial cells and cleaved by mild acid hydrolysis to yield the OPS. The OPS was studied by sugar and methylation analyses, along with 1D and 2D (1)H and (13)C NMR spectroscopy. The established structure of the linear tetrasaccharide repeating unit was found to be unique among known bacterial polysaccharide structures. A peculiar component of the L-19 OPS was an amide of glucuronic acid with 2-amino-1,3-propanediol (2-amino-2-deoxyglycerol) (GroN). The O-antigen gene cluster of L-19 between the conserved genes galF and gnd was sequenced, and gene functions were tentatively assigned by a comparison with sequences in the available databases and found to be in agreement with the OPS structure. Except for putative genes for synthesis and transfer of GroN, the sequences in the L-19 O-antigen gene cluster were little related to those of reference strains of the 174 known E. coli O-serogroups. The data obtained suggest that L-19 can be considered as a candidate for a new E. coli O-serogroup.
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Copper catalyzed C-O bond formation via oxidative cross-coupling reaction of aldehydes and ethers.
Org. Biomol. Chem.
PUBLISHED: 07-18-2014
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A practical and efficient construction of C-O bonds via oxidative cross-coupling reaction of aldehydes and ethers has been realized under open air. When 2 mol% copper was used as the catalyst, various ?-acyloxy ethers were obtained with up to 93% isolated yield.
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Quantitative network mapping of the human kinome interactome reveals new clues for rational kinase inhibitor discovery and individualized cancer therapy.
Oncotarget
PUBLISHED: 07-09-2014
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The human kinome is gaining importance through its promising cancer therapeutic targets, yet no general model to address the kinase inhibitor resistance has emerged. Here, we constructed a systems biology-based framework to catalogue the human kinome, including 538 kinase genes, in the broader context of the human interactome. Specifically, we constructed three networks: a kinase-substrate interaction network containing 7,346 pairs connecting 379 kinases to 36,576 phosphorylation sites in 1,961 substrates, a protein-protein interaction network (PPIN) containing 92,699 pairs, and an atomic resolution PPIN containing 4,278 pairs. We identified the conserved regulatory phosphorylation motifs (e.g., Ser/Thr-Pro) using a sequence logo analysis. We found the typical anticancer target selection strategy that uses network hubs as drug targets, might lead to a high adverse drug reaction risk. Furthermore, we found the distinct network centrality of kinases creates a high anticancer drug resistance risk by feedback or crosstalk mechanisms within cellular networks. This notion is supported by the systematic network and pathway analyses that anticancer drug resistance genes are significantly enriched as hubs and heavily participate in multiple signaling pathways. Collectively, this comprehensive human kinome interactome map sheds light on anticancer drug resistance mechanisms and provides an innovative resource for rational kinase inhibitor design.
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DCE-MRI assessment of the effect of Epstein-Barr virus-encoded latent membrane protein-1 targeted DNAzyme on tumor vasculature in patients with nasopharyngeal carcinomas.
BMC Cancer
PUBLISHED: 07-02-2014
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EBV-encoded latent membrane protein 1 (EBV-LMP1) is an important oncogenic protein for nasopharyngeal carcinoma (NPC) and has been shown to engage a plethora of signaling pathways. Correspondingly, an LMP1-targeted DNAzyme was found to inhibit the growth of NPC cells both in vivo and in vitro by suppressing cell proliferation and inducing apoptosis. However, it remains unknown whether an LMP1-targeted DNAzyme would affect the vasculature of NPC. Dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) has been applied in the clinical trials of anti-angiogenic drugs for more than ten years, and Ktrans has been recommended as a primary endpoint. Therefore, the objective of the current study was to use DCE-MRI to longitudinally study the effect of an EBV-LMP1-targeted DNAzyme on the vasculature of patients with NPC.
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Arabidopsis LIP5, a positive regulator of multivesicular body biogenesis, is a critical target of pathogen-responsive MAPK cascade in plant basal defense.
PLoS Pathog.
PUBLISHED: 07-01-2014
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Multivesicular bodies (MVBs) play essential roles in many cellular processes. The MVB pathway requires reversible membrane association of the endosomal sorting complexes required for transports (ESCRTs) for sustained protein trafficking. Membrane dissociation of ESCRTs is catalyzed by the AAA ATPase SKD1, which is stimulated by LYST-interacting protein 5 (LIP5). We report here that LIP5 is a target of pathogen-responsive mitogen-activated protein kinases (MPKs) and plays a critical role in plant basal resistance. Arabidopsis LIP5 interacts with MPK6 and MPK3 and is phosphorylated in vitro by activated MPK3 and MPK6 and in vivo upon expression of MPK3/6-activating NtMEK2DD and pathogen infection. Disruption of LIP5 has little effects on flg22-, salicylic acid-induced defense responses but compromises basal resistance to Pseudomonas syringae. The critical role of LIP5 in plant basal resistance is dependent on its ability to interact with SKD1. Mutation of MPK phosphorylation sites in LIP5 does not affect interaction with SKD1 but reduces the stability and compromises the ability to complement the lip5 mutant phenotypes. Using the membrane-selective FM1-43 dye and transmission electron microscopy, we demonstrated that pathogen infection increases formation of both intracellular MVBs and exosome-like paramural vesicles situated between the plasma membrane and the cell wall in a largely LIP5-dependent manner. These results indicate that the MVB pathway is positively regulated by pathogen-responsive MPK3/6 through LIP5 phosphorylation and plays a critical role in plant immune system likely through relocalization of defense-related molecules.
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[Interferon-gamma receptor 1 deficiency in a 19-month-old child: case report and literature review].
Zhonghua Er Ke Za Zhi
PUBLISHED: 06-28-2014
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To analyze the clinical manifestation of interferon gamma receptor 1 deficiency (IFN-?R1 deficiency) and to improve the recognition of this disease in children, decrease diagnostic errors and missed diagnosis.
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Molecular mechanism of SCARB2-mediated attachment and uncoating of EV71.
Protein Cell
PUBLISHED: 06-24-2014
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Unlike the well-established picture for the entry of enveloped viruses, the mechanism of cellular entry of non-enveloped eukaryotic viruses remains largely mysterious. Picornaviruses are representative models for such viruses, and initiate this entry process by their functional receptors. Here we present the structural and functional studies of SCARB2, a functional receptor of the important human enterovirus 71 (EV71). SCARB2 is responsible for attachment as well as uncoating of EV71. Differences in the structures of SCARB2 under neutral and acidic conditions reveal that SCARB2 undergoes a pivotal pH-dependent conformational change which opens a lipid-transfer tunnel to mediate the expulsion of a hydrophobic pocket factor from the virion, a pre-requisite for uncoating. We have also identified the key residues essential for attachment to SCARB2, identifying the canyon region of EV71 as mediating the receptor interaction. Together these results provide a clear understanding of cellular attachment and initiation of uncoating for enteroviruses.
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Development of a Single Nucleotide Polymorphism DNA Microarray for the Detection and Genotyping of the SARS Coronavirus.
J. Microbiol. Biotechnol.
PUBLISHED: 06-22-2014
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Severe acute respiratory syndrome (SARS), a disease that spread widely in the world during late 2002 to 2004, severely threatened public health. Although there have been no reported infections since 2004, the extremely pathogenic SARS coronavirus (SARS-CoV), as the causative agent of SARS, has recently been identified in animals, showing the potential for the re-emergence of this disease. Previous studies showed that 27 single nucleotide polymorphism (SNP) mutations among the spike (S) gene of this virus are correlated closely with the SARS pathogenicity and epidemicity. We have developed a SNP DNA microarray in order to detect and genotype these SNPs, and to obtain related information on the pathogenicity and epidemicity of a given strain. The microarray was hybridized with PCR products amplified from cDNAs obtained from different SARS-CoV strains. We were able to detect 24 SNPs and determine the type of a given strain. The hybridization profile showed that 19 samples were detected and genotyped correctly by using our microarray, with 100% accuracy. Our microarray provides a novel method for the detection and epidemiological surveillance of SARS-CoV.
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H2O2 mediates the crosstalk of brassinosteroid and abscisic acid in tomato responses to heat and oxidative stresses.
J. Exp. Bot.
PUBLISHED: 06-04-2014
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The production of H2O2 is critical for brassinosteroid (BR)- and abscisic acid (ABA)-induced stress tolerance in plants. In this study, the relationship between BR and ABA in the induction of H2O2 production and their roles in response to heat and paraquat (PQ) oxidative stresses were studied in tomato. Both BR and ABA induced increases in RBOH1 gene expression, NADPH oxidase activity, apoplastic H2O2 accumulation, and heat and PQ stress tolerance in wild-type plants. BR could only induced transient increases in these responses in the ABA biosynthetic mutant notabilis (not), whereas ABA induced strong and prolonged increases in these responses in the BR biosynthetic mutant d (^im) compared with wild-type plants. ABA levels were reduced in the BR biosynthetic mutant but could be elevated by exogenous BR. Silencing of RBOH1 compromised BR-induced apoplastic H2O2 production, ABA accumulation, and PQ stress responses; however, ABA-induced PQ stress responses were largely unchanged in the RBOH1-silenced plants. BR induces stress tolerance involving a positive feedback mechanism in which BR induces a rapid and transient H2O2 production by NADPH oxidase. The process in turn triggers increased ABA biosynthesis, leading to further increases in H2O2 production and prolonged stress tolerance. ABA induces H2O2 production in both the apoplastic and chloroplastic compartments.
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Studying tumorigenesis through network evolution and somatic mutational perturbations in the cancer interactome.
Mol. Biol. Evol.
PUBLISHED: 05-31-2014
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Cells govern biological functions through complex biological networks. Perturbations to networks may drive cells to new phenotypic states, for example, tumorigenesis. Identifying how genetic lesions perturb molecular networks is a fundamental challenge. This study used large-scale human interactome data to systematically explore the relationship among network topology, somatic mutation, evolutionary rate, and evolutionary origin of cancer genes. We found the unique network centrality of cancer proteins, which is largely independent of gene essentiality. Cancer genes likely have experienced a lower evolutionary rate and stronger purifying selection than those of noncancer, Mendelian disease, and orphan disease genes. Cancer proteins tend to have ancient histories, likely originated in early metazoan, although they are younger than proteins encoded by Mendelian disease genes, orphan disease genes, and essential genes. We found that the protein evolutionary origin (age) positively correlates with protein connectivity in the human interactome. Furthermore, we investigated the network-attacking perturbations due to somatic mutations identified from 3,268 tumors across 12 cancer types in The Cancer Genome Atlas. We observed a positive correlation between protein connectivity and the number of nonsynonymous somatic mutations, whereas a weaker or insignificant correlation between protein connectivity and the number of synonymous somatic mutations. These observations suggest that somatic mutational network-attacking perturbations to hub genes play an important role in tumor emergence and evolution. Collectively, this work has broad biomedical implications for both basic cancer biology and the development of personalized cancer therapy.
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Auxin Depletion from the Leaf Axil Conditions Competence for Axillary Meristem Formation in Arabidopsis and Tomato.
Plant Cell
PUBLISHED: 05-21-2014
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The enormous variation in architecture of flowering plants is based to a large extent on their ability to form new axes of growth throughout their life span. Secondary growth is initiated from groups of pluripotent cells, called meristems, which are established in the axils of leaves. Such meristems form lateral organs and develop into a side shoot or a flower, depending on the developmental status of the plant and environmental conditions. The phytohormone auxin is well known to play an important role in inhibiting the outgrowth of axillary buds, a phenomenon known as apical dominance. However, the role of auxin in the process of axillary meristem formation is largely unknown. In this study, we show in the model species Arabidopsis thaliana and tomato (Solanum lycopersicum) that auxin is depleted from leaf axils during vegetative development. Disruption of polar auxin transport compromises auxin depletion from the leaf axil and axillary meristem initiation. Ectopic auxin biosynthesis in leaf axils interferes with axillary meristem formation, whereas repression of auxin signaling in polar auxin transport mutants can largely rescue their branching defects. These results strongly suggest that depletion of auxin from leaf axils is a prerequisite for axillary meristem formation during vegetative development.
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Chloroplastic thioredoxin-f and thioredoxin-m1/4 play important roles in brassinosteroids-induced changes in CO2 assimilation and cellular redox homeostasis in tomato.
J. Exp. Bot.
PUBLISHED: 05-20-2014
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Chloroplast thioredoxins (TRXs) and glutathione function as redox messengers in the regulation of photosynthesis. In this work, the roles of chloroplast TRXs in brassinosteroids (BRs)-induced changes in cellular redox homeostasis and CO2 assimilation were studied in the leaves of tomato plants. BRs-deficient d (^im) plants showed decreased transcripts of TRX-f, TRX-m2, TRX-m1/4, and TRX-x, while exogenous BRs significantly induced CO2 assimilation and the expression of TRX-f, TRX-m2, TRX-m1/4, and TRX-x. Virus-induced gene silencing (VIGS) of the chloroplast TRX-f, TRX-m2, TRX-m1/4, and TRX-y genes individually increased membrane lipid peroxidation and accumulation of 2-Cys peroxiredoxin dimers, and decreased the activities of the ascorbate-glutathione cycle enzymes and the ratio of reduced glutathione to oxidized glutathione (GSH/GSSG) in the leaves. Furthermore, partial silencing of TRX-f, TRX-m2, TRX-m1/4, and TRX-y resulted in decreased expression of genes involved in the Benson-Calvin cycle and decreased activity of the associated enzymes. Importantly, the BRs-induced increase in CO2 assimilation and the increased expression and activities of antioxidant- and photosynthesis-related genes and enzymes were compromised in the partially TRX-f- and TRX-m1/4-silenced plants. All of these results suggest that TRX-f and TRX-m1/4 are involved in the BRs-induced changes in CO2 assimilation and cellular redox homeostasis in tomato.
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[Experimental study on vascular endothelial growth factor 165 gene-modified rat hair follicle stem cells mediated by lentiviral vector].
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi
PUBLISHED: 05-07-2014
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To obtain rat hair follicle stem cells (rHFSCs) which can constantly and highly express vascular endothelial growth factor 165 (VEGF165), and to observe the expression of VEGF165 gene in rat HFSCs.
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Culture and characterization of rat hair follicle stem cells.
Cytotechnology
PUBLISHED: 05-03-2014
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The purpose of this study was to establish methods for isolation, culture, expansion, and characterization of rat hair follicle stem cells (rHFSCs). Hair follicles were harvested from 1-week-old Sprague-Dawley rats and digested with dispase and collagenase IV. The bulge of the hair follicle was dissected under a microscope and cultured in Dulbecco's modified Eagle's medium/F12 supplemented with KnockOut™ Serum Replacement serum substitute, penicillin-streptomycin, L-glutamine, non-essential amino acids, epidermal growth factor, basic fibroblast growth factor, polyhydric alcohol, and hydrocortisone. The rHFSCs were purified using adhesion to collagen IV. Cells were characterized by detecting marker genes with immunofluorescent staining and real-time polymerase chain reaction (PCR). The proliferation and vitality of rHFSCs at different passages were evaluated. The cultured rHFSCs showed typical cobblestone morphology with good adhesion and colony-forming ability. Expression of keratin 15, integrin ?6, and integrin ?1 were shown by immunocytochemistry staining. On day 1-2, the cells were in the latent phase. On day 5-6, the cells were in the logarithmic phase. Cell vitality gradually decreased from the 7th passage. Real-time PCR showed that the purified rHFSCs had good vitality and proliferative capacity and contained no keratinocytes. Highly purified rHFSCs can be obtained using tissue culture and adhesion to collagen IV. The cultured cells had good proliferative capacity and could therefore be a useful cell source for tissue-engineered hair follicles, vessels, and skin.
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Expression, purification and characterization of recombinant toxins consisting of truncated gastrin 17 and Pseudomonas exotoxin.
Protein Pept. Lett.
PUBLISHED: 04-18-2014
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Gastric cancer is a major cause of mortality and morbidity around world. However the effectiveness of the current approaches to the diagnosis and treatment of gastric cancer is limited. Recombinant targeted toxins may represent a novel direction of cancer therapy. In this study, we aimed to explore whether recombinant toxins fused with the truncated forms of G17 could target to kill cancer cells by recognizing CCK2R. Four recombinant Pseudomonas toxins PE38 fused with the forward or reverse truncated forms of G17 (G14 and G13) were successfully constructed, expressed, and purified. Their characteristics were further analyzed by SDS-PAGE, western blot and indirect immunofluorescence assay. The cytotoxicity assay demonstrated that only reversely fused recombinant toxins rG14PE38 and rG13PE38 exhibited certain toxicity on several cancer cell lines, and a competition assay indicated that the binding of the reverse gastrin-endotoxin to CCK2R (+) cells may be mediated by interaction between gastrin/gastrin-like and CCK2R.
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A novel esterase from a marine metagenomic library exhibiting salt tolerance ability.
J. Microbiol. Biotechnol.
PUBLISHED: 03-18-2014
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A putative lipolytic enzyme gene, named as est9x, was obtained from a marine microbial metagenome of the South China Sea. Sequence analysis showed that Est9X shares lower than 27% sequence identities with the characterized lipolytic enzymes, but possesses a catalytic triad highly conserved in lipolytic enzymes of the ?/? hydrolase superfamily. By phylogenetic tree construction, Est9X was grouped into a new lipase/esterase family. To understand Est9X protein in depth, it was recombinantly expressed, purified, and biochemically characterized. Within potential hydrolytic activities, only lipase/esterase activity was detected for Est9X, confirming its identity as a lipolytic enzyme. When using p-nitrophenol esters with varying lengths of fatty acid as substrates, Est9X exhibited the highest activity to the C2 substrate, indicating it is an esterase. The optimal activity of Est9X occurred at a temperature of 65°C, and Est9X was pretty stable below the optimum temperature. Distinguished from other salttolerant esterases, Est9X's activity was tolerant to and even promoted by as high as 4 M NaCl. Our results imply that Est9X is a unique esterase and could be a potential candidate for industrial application under extreme conditions.
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Gelatin-chondroitin-6-sulfate-hyaluronic acid scaffold seeded with vascular endothelial growth factor 165 modified hair follicle stem cells as a three-dimensional skin substitute.
Stem Cell Res Ther
PUBLISHED: 02-26-2014
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In the field of skin tissue engineering, gelatin-chondroitin-6-sulfate-hyaluronic acid (Gel-C6S-HA) stents are a suitable bio skin substitute. The purpose was to investigate the effect of genetically-modified hair follicle stem cells (HFSCs), combined with Gel-C6S-HA scaffolds, on the vascularization of tissue-engineered skin.
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Hydrogen peroxide mediates abscisic acid-induced HSP70 accumulation and heat tolerance in grafted cucumber plants.
Plant Cell Environ.
PUBLISHED: 02-26-2014
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Root-shoot communications play important roles in plant stress responses. Here, we examined the roles of root-sourced signals in the shoot response to heat in cucumber plants. Cucumber plants grafted onto their own roots and luffa roots were exposed to aerial and root-zone heat to examine their tolerance by assessing the levels of oxidative stress, PSII photoinhibition, accumulation of abscisic acid (ABA), H2 O2 and heat shock protein (HSP) 70 using immunoblotting, chlorophyll fluorescence, immunoassay, CeCl3 staining and Western blotting, respectively. Grafting onto the luffa rootstock enhanced the shoot tolerance to the heat. This enhanced tolerance was associated with increased accumulation of ABA and apoplastic H2 O2 , RBOH transcripts and HSP70 expression and a decrease in oxidative stress in the shoots. The increases in the ABA and H2 O2 concentrations in the shoots were attributed to an increase in ABA transport from roots and an increase in ABA biosynthesis in the shoots when the root-zone and shoots were heat stressed, respectively. Inhibition of H2 O2 accumulation compromised luffa rootstock-induced HSP70 expression and heat tolerance. These results suggest that, under heat stress, ABA triggers the expression of HSP70 in an apoplastic H2 O2 -dependent manner, implicating the role of an ABA-dependent H2 O2 -driven mechanism in a systemic response involving root-shoot communication.
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The sub/supra-optimal temperature-induced inhibition of photosynthesis and oxidative damage in cucumber leaves are alleviated by grafting onto figleaf gourd/luffa rootstocks.
Physiol Plant
PUBLISHED: 02-22-2014
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Shoot-root communication is involved in plant stress responses, but its mechanism is largely unknown. To determine the role of roots in stress tolerance, cucumber (Cucumis sativus) shoots from plants with roots of their own or with figleaf gourd (Cucurbita ficifolia, a chilling-tolerant species) or luffa (Luffa cylindrica (L.) M. Roem., a heat-tolerant species) rootstocks were exposed to low (18/13°C), optimal (27/22°C) and high (36/31°C) temperatures, respectively. Grafting onto figleaf gourd and luffa rootstocks significantly alleviated chilling and heat-induced reductions, respectively, in biomass production and CO2 assimilation capacity in the shoots, while levels of lipid peroxidation and protein oxidation were decreased. Figleaf gourd and luffa rootstocks upregulated a subset of stress-responsive genes involved in signal transduction (MAPK1 and RBOH), transcriptional regulation (MYB and MYC), protein protection (HSP45.9 and HSP70), the antioxidant response (Cu/Zn-SOD, cAPX and GR), and photosynthesis (RBCL, RBCS, RCA and FBPase) at low and high growth temperatures, respectively, and this was accompanied by increased activity of the encoded enzymes and reduced glutathione redox homeostasis in the leaves. Moreover, Heat Shock Protein 70 (HSP70) expression in cucumber leaves was strongly induced by the luffa rootstock at the high growth temperature but slightly induced by the figleaf gourd rootstock at low or high growth temperatures. These results indicate that rootstocks could induce significant changes in the transcripts of stress-responsive and defense-related genes, and the ROS scavenging activity via unknown signals, especially at stressful growth temperatures, and this is one of mechanisms involved in the grafting-induced stress tolerance.
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The perplexing role of autophagy in plant innate immune responses.
Mol. Plant Pathol.
PUBLISHED: 02-19-2014
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Autophagy is a major intracellular process for the degradation of cytosolic macromolecules and organelles in the lysosomes or vacuoles for the purposes of regulating cellular homeostasis and protein and organelle quality control. In complex metazoan organisms, autophagy is highly engaged during the immune responses through interfaces either directly with intracellular pathogens or indirectly with immune signalling molecules. Studies over the last decade or so have also revealed a number of important ways in which autophagy shapes plant innate immune responses. First, autophagy promotes defence-associated hypersensitive cell death induced by avirulent or related pathogens, but restricts unnecessary or disease-associated spread of cell death. This elaborate regulation of plant host cell death by autophagy is critical during plant immune responses to the types of plant pathogens that induce cell death, which include avirulent biotrophic pathogens and necrotrophic pathogens. Second, autophagy modulates defence responses regulated by salicylic acid and jasmonic acid, thereby influencing plant basal resistance to both biotrophic and necrotrophic pathogens. Third, there is an emerging role of autophagy in virus-induced RNA silencing, either as an antiviral collaborator for targeted degradation of viral RNA silencing suppressors or an accomplice of viral RNA silencing suppressors for targeted degradation of key components of plant cellular RNA silencing machinery. In this review, we summarize this important progress and discuss the potential significance of the perplexing role of autophagy in plant innate immunity.
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Effects of entecavir on peripheral blood lymphocyte profiles in chronic hepatitis B patients with suboptimal responses to adefovir.
Clin. Exp. Pharmacol. Physiol.
PUBLISHED: 02-17-2014
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The aim of the present study was to assess the long-term impact of entecavir (ETV) on T, B and natural killer (NK) cell immunity in patients with suboptimal responses to adefovir (SRA) chronic hepatitis B (CHB). Thirty SRA CHB patients and 20 age- and gender-matched healthy controls (HC) completed at least 6 months of ETV treatment. Hepatitis B virus (HBV) DNA loads, alanine aminotransferase (ALT) and aspartate aminotransferase (AST) and the frequency of different subsets of T, B and NK cells in individual subjects were measured. There were smaller numbers of CD3(-) CD56(+) and CD244(+) NK cells, CD3(+) CD8(+) T cells and cytokine-secreting CD4(+) T cells, but greater numbers of CD3(+) CD4(+) , CD4(+) CD25(+) Foxp3(+) , CD4(+) CD25(+) CD127(low) T cells and CD19(+) CD27(+) B cells, detected in SRA patients. After switching to ETV monotherapy, the levels of HBV DNA and hepatitis B s antigen, as well as hepatitis B e antigen seropositivity, decreased gradually, accompanied by decreases in ALT and AST levels. Furthermore, the number of NK, CD8(+) and cytokine-secreting CD4(+) T cells increased, whereas the number of CD4(+) , CD4(+) CD25(+) Foxp3(+) , CD4(+) CD25(+) CD127(low) T cells and CD19(+) CD27(+) B cells decreased, in SRA CHB patients. The frequency of CD4(+) interferon-?-positive T cells was negatively associated with serum HBV DNA levels. Thus, treatment with ETV inhibits HBV replication, modulates T and NK cell immunity and improves liver function in SRA CHB patients.
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FGFR3 induces degradation of BMP type I receptor to regulate skeletal development.
Biochim. Biophys. Acta
PUBLISHED: 02-16-2014
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Fibroblast growth factors (FGFs) and their receptors (FGFRs) play significant roles in vertebrate organogenesis and morphogenesis. FGFR3 is a negative regulator of chondrogenesis and multiple mutations with constitutive activity of FGFR3 result in achondroplasia, one of the most common dwarfisms in humans, but the molecular mechanism remains elusive. In this study, we found that chondrocyte-specific deletion of BMP type I receptor a (Bmpr1a) rescued the bone overgrowth phenotype observed in Fgfr3 deficient mice by reducing chondrocyte differentiation. Consistently, using in vitro chondrogenic differentiation assay system, we demonstrated that FGFR3 inhibited BMPR1a-mediated chondrogenic differentiation. Furthermore, we showed that FGFR3 hyper-activation resulted in impaired BMP signaling in chondrocytes of mouse growth plates. We also found that FGFR3 inhibited BMP-2- or constitutively activated BMPR1-induced phosphorylation of Smads through a mechanism independent of its tyrosine kinase activity. We found that FGFR3 facilitates BMPR1a to degradation through Smurf1-mediated ubiquitination pathway. We demonstrated that down-regulation of BMP signaling by BMPR1 inhibitor dorsomorphin led to the retardation of chondrogenic differentiation, which mimics the effect of FGF-2 on chondrocytes and BMP-2 treatment partially rescued the retarded growth of cultured bone rudiments from thanatophoric dysplasia type II mice. Our findings reveal that FGFR3 promotes the degradation of BMPR1a, which plays an important role in the pathogenesis of FGFR3-related skeletal dysplasia.
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Single-molecule motions enable direct visualization of biomolecular interactions in solution.
Nat. Methods
PUBLISHED: 01-25-2014
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Biomolecular interactions are generally accompanied by modifications in size and charge of biomolecules at the nanometer scale. Here we describe a single-molecule method to sense these changes in real time based on statistical learning of diffusive and electric field-induced motion parameters of a trapped molecule in solution. We demonstrate the approach by resolving a monomer-trimer mixture along a protein dissociation pathway and visualizing the binding-unbinding kinetics of a single DNA molecule.
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Combined neuroendocrine carcinoma and adenocarcinoma in the stomach: A case report.
Oncol Lett
PUBLISHED: 01-24-2014
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Neuroendocrine carcinoma and adenocarcinoma existing in the stomach simultaneously is extremely rare. This report presents a 65-year-old male patient who was diagnosed with three types of malignant tumors in the stomach, neuroendocrine carcinoma (NEC), moderately differentiated adenocarcinoma and mucinous adenocarcinoma. In addition, the NEC and moderately differentiated adenocarcinoma existed in the same lesion and, therefore, was referred to as a mixed adenocarcinoma - NEC tumor. The patient underwent laparoscopic-assisted D2 radical total gastrectomy, Roux-en-Y esophagus-jejunum anastomosis and received FOLFOX chemotherapy for six cycles 3 weeks after surgery. Follow-up determined that the patient survived and was tumor-free 12 months after surgery. In conclusion, radical surgery combined with chemotherapy can effectively improve the prognosis of patients with these three specific tumor types simultaneously in the stomach.
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Vibrio parahaemolyticus enolase is an adhesion-related factor that binds plasminogen and functions as a protective antigen.
Appl. Microbiol. Biotechnol.
PUBLISHED: 01-16-2014
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Vibrio parahaemolyticus, an emerging food and waterborne pathogen, is a leading cause of seafood poisoning worldwide. Surface proteins can directly participate in microbial virulence by facilitating pathogen dissemination via interactions with host factors. Screening and identification of protective antigens is important for developing therapies against V. parahaemolyticus infections. Here, we systematically characterized a novel immunogenic enolase of V. parahaemolyticus. The enolase gene of V. parahaemolyticus ATCC33847 was cloned, sequenced, and expressed in Escherichia coli BL21. Enzymatic assays revealed that the purified recombinant V. parahaemolyticus enolase protein catalyzes the dehydration of 2-phospho-D-glycerate to phosphoenolpyruvate. Western blot analysis showed that V. parahaemolyticus enolase was detectable in the extracellular, outer membrane (OM) and cytoplasmic protein fractions using antibodies against the recombinant enolase. Surface expression of enolase was further confirmed by immunogold staining and mass spectrometry (liquid chromatography-tandem mass spectrometry) analysis of OM protein profiles. Notably, V. parahaemolyticus enolase was identified as a human plasminogen-binding protein with the enzyme-linked immunosorbent assay. The values obtained for adherence and inhibition suggest a role of surface-exposed enolase in epithelial adherence of V. parahaemolyticus. We further showed that enolase confers efficient immunity against challenge with a lethal dose of V. parahaemolyticus in a mouse model. To our knowledge, this is the first study to demonstrate the plasminogen-binding activity of enolase that is an adhesion-related factor of V. parahaemolyticus. Our findings collectively imply that enolase plays important roles in pathogenicity, supporting its utility as a novel vaccine candidate against V. parahaemolyticus infection.
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Structure elucidation and gene cluster annotation of the O-antigen of Escherichia coli O39; application of anhydrous trifluoroacetic acid for selective cleavage of glycosidic linkages.
Carbohydr. Res.
PUBLISHED: 01-12-2014
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O-Polysaccharide (O-antigen) accompanied by a minor mannan was isolated from the lipopolysaccharide of Escherichia coli O39 and studied by component analyses, methylation, Smith degradation, mass spectrometry, and 1D and 2D NMR spectroscopy. In addition, a new approach, solvolysis with anhydrous trifluoroacetic acid, was applied to cleave selectively the rhamnosidic linkage. The following structure of the O-polysaccharide was established: ?--D-Galpl-->3-->3)-?-D-Quip4N(R3Hb)-(1-->2)-?-D-Manp-(l-->4)-?-L-Rhap-(1-->3)-?-D-GlcpNAc-(1--> where D-Qui4N(R3Hb) indicates 4,6-dideoxy-4-[(R)-3-hydroxybutanoylamino]-d-glucose. The O-antigen gene cluster of E. coli O39 has been sequenced. The gene functions were tentatively assigned by a comparison with sequences in the available databases and found to be in agreement with the O-polysaccharide structure.
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Role of H2O2 dynamics in brassinosteroid-induced stomatal closure and opening in Solanum lycopersicum.
Plant Cell Environ.
PUBLISHED: 01-07-2014
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Brassinosteroids (BRs) are essential for plant growth and development; however, their roles in the regulation of stomatal opening or closure remain obscure. Here, the mechanism underlying BR-induced stomatal movements is studied. The effects of 24-epibrassinolide (EBR) on the stomatal apertures of tomato (Solanum lycopersicum) were measured by light microscopy using epidermal strips of wild type (WT), the abscisic acid (ABA)-deficient notabilis (not) mutant, and plants silenced for SlBRI1, SlRBOH1 and SlGSH1. EBR induced stomatal opening within an appropriate range of concentrations, whereas high concentrations of EBR induced stomatal closure. EBR-induced stomatal movements were closely related to dynamic changes in H(2)O(2) and redox status in guard cells. The stomata of SlRBOH1-silenced plants showed a significant loss of sensitivity to EBR. However, ABA deficiency abolished EBR-induced stomatal closure but did not affect EBR-induced stomatal opening. Silencing of SlGSH1, the critical gene involved in glutathione biosynthesis, disrupted glutathione redox homeostasis and abolished EBR-induced stomatal opening. The results suggest that transient H(2)O(2) production is essential for poising the cellular redox status of glutathione, which plays an important role in BR-induced stomatal opening. However, a prolonged increase in H(2)O(2) facilitated ABA signalling and stomatal closure.
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Structure and gene cluster of the O-antigen of Escherichia coli O36.
Carbohydr. Res.
PUBLISHED: 01-04-2014
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The O-polysaccharide (O-antigen) of Escherichia coli O36 was isolated from the lipopolysaccharide and studied by sugar analyses and Smith degradation along with (1)H and (13)C NMR spectroscopy. The following structure of the branched pentasaccharide repeating unit was established, which is unique among the known structures of bacterial polysaccharides: The O-antigen gene cluster of E. coli O36 has been sequenced. The gene functions were tentatively assigned by comparison with sequences in the available databases and found to be in full agreement with the O-polysaccharide structure.
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Impaired Autophagy Contributes to Adverse Cardiac Remodeling in Acute Myocardial Infarction.
PLoS ONE
PUBLISHED: 01-01-2014
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Autophagy is activated in ischemic heart diseases, but its dynamics and functional roles remain unclear and controversial. In this study, we investigated the dynamics and role of autophagy and the mechanism(s), if any, during postinfarction cardiac remodeling.
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Role and regulation of autophagy in heat stress responses of tomato plants.
Front Plant Sci
PUBLISHED: 01-01-2014
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As sessile organisms, plants are constantly exposed to a wide spectrum of stress conditions such as high temperature, which causes protein misfolding. Misfolded proteins are highly toxic and must be efficiently removed to reduce cellular proteotoxic stress if restoration of native conformations is unsuccessful. Although selective autophagy is known to function in protein quality control by targeting degradation of misfolded and potentially toxic proteins, its role and regulation in heat stress responses have not been analyzed in crop plants. In the present study, we found that heat stress induced expression of autophagy-related (ATG) genes and accumulation of autophagosomes in tomato plants. Virus-induced gene silencing (VIGS) of tomato ATG5 and ATG7 genes resulted in increased sensitivity of tomato plants to heat stress based on both increased development of heat stress symptoms and compromised photosynthetic parameters of heat-stressed leaf tissues. Silencing of tomato homologs for the selective autophagy receptor NBR1, which targets ubiquitinated protein aggregates, also compromised tomato heat tolerance. To better understand the regulation of heat-induced autophagy, we found that silencing of tomato ATG5, ATG7, or NBR1 compromised heat-induced expression of not only the targeted genes but also other autophagy-related genes. Furthermore, we identified two tomato genes encoding proteins highly homologous to Arabidopsis WRKY33 transcription factor, which has been previously shown to interact physically with an autophagy protein. Silencing of tomato WRKY33 genes compromised tomato heat tolerance and reduced heat-induced ATG gene expression and autophagosome accumulation. Based on these results, we propose that heat-induced autophagy in tomato is subject to cooperative regulation by both WRKY33 and ATG proteins and plays a critical role in tomato heat tolerance, mostly likely through selective removal of heat-induced protein aggregates.
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Short- and long-term effects of vertebroplastic bone cement on cancellous bone.
J Mech Behav Biomed Mater
PUBLISHED: 01-01-2014
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Vertebroplasty using poly(methyl methacrylate) (PMMA) bone cement is the most common method to treat osteoporotic vertebral fractures. However, several questions of interest remain to be clarified, including how does PMMA affect the cement-bone interface area and surrounding bone tissue, can damaged bone tissues be repaired, how will PMMA change the bone interface over the long-term, and what happens to PMMA itself? The purpose of this study is to investigate these concerns and provide a basis for clinical evaluation. We made bone defects in the lumbar vertebrae of New Zealand rabbits as a model of osteoporosis and injected them with bone cement. A mechanical testing machine was used to perform axial compression, three-point bending, and twisting resistance tests to observe and investigate the short- and long-term biomechanical properties of PMMA after implantation. Optical, fluorescence, scanning electron microscopy, and nanoindentation were used to observe the changes in the interface microstructure. PMMA can rapidly establish the strong support with stable function in the near future. Biomechanical experiments showed that biomechanical property of bone cement group was significantly higher than those in the other two groups (P<0.05) biomechanical property of bone cement group may decline with the time, but it?s still better than that of OP in the control group (P<0.05). Histomorphological observation result shows that under osteoporosis state the bone grows slower, also bone?s rebuilding time extended. And in the later period, main bone?s continuous osteoporosis has some impact on the interface. Nano-indentation testing shows that the young modulus and stiffness of the interface among bone, material and interface were significantly differences (P<0.05). Bone cement had gave the best nano indentation hardness, then was interface and bone tissue. PMMA bone cement was able to quickly support and stabilize the defect in the short term, and bone growth restarted at the bone interface and was tightly integrated. However, over the long-term, fluorescent signal was weakened, osteoclasts appeared, the mechanical indicators for both the interface and the whole vertebra decreased, and bone resorption was eventually greater than bone formation, resulting in bone loss. Therefore, vertebroplasty is not the end of treatment, and we need to further study ways to improve the bone cement material, which is crucial for long-term vertebroplasty efficacy, to better treat osteoporosis.
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The efficacy and safety of different kinds of laparoscopic cholecystectomy: a network meta analysis of 43 randomized controlled trials.
PLoS ONE
PUBLISHED: 01-01-2014
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We conducted a network meta analysis (NMA) to compare different kinds of laparoscopic cholecystectomy [LC] (single port [SPLC], two ports [2PLC], three ports [3PLC], and four ports laparoscopic cholecystectomy [4PLC], and four ports mini-laparoscopic cholecystectomy [mini-4PLC]).
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E3 ubiquitin ligase CHIP and NBR1-mediated selective autophagy protect additively against proteotoxicity in plant stress responses.
PLoS Genet.
PUBLISHED: 01-01-2014
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Plant stress responses require both protective measures that reduce or restore stress-inflicted damage to cellular structures and mechanisms that efficiently remove damaged and toxic macromolecules, such as misfolded and damaged proteins. We have recently reported that NBR1, the first identified plant autophagy adaptor with a ubiquitin-association domain, plays a critical role in plant stress tolerance by targeting stress-induced, ubiquitinated protein aggregates for degradation by autophagy. Here we report a comprehensive genetic analysis of CHIP, a chaperone-associated E3 ubiquitin ligase from Arabidopsis thaliana implicated in mediating degradation of nonnative proteins by 26S proteasomes. We isolated two chip knockout mutants and discovered that they had the same phenotypes as the nbr1 mutants with compromised tolerance to heat, oxidative and salt stresses and increased accumulation of insoluble proteins under heat stress. To determine their functional interactions, we generated chip nbr1 double mutants and found them to be further compromised in stress tolerance and in clearance of stress-induced protein aggregates, indicating additive roles of CHIP and NBR1. Furthermore, stress-induced protein aggregates were still ubiquitinated in the chip mutants. Through proteomic profiling, we systemically identified heat-induced protein aggregates in the chip and nbr1 single and double mutants. These experiments revealed that highly aggregate-prone proteins such as Rubisco activase and catalases preferentially accumulated in the nbr1 mutant while a number of light-harvesting complex proteins accumulated at high levels in the chip mutant after a relatively short period of heat stress. With extended heat stress, aggregates for a large number of intracellular proteins accumulated in both chip and nbr1 mutants and, to a greater extent, in the chip nbr1 double mutant. Based on these results, we propose that CHIP and NBR1 mediate two distinct but complementary anti-proteotoxic pathways and protein's propensity to aggregate under stress conditions is one of the critical factors for pathway selection of protein degradation.
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RBOH1-dependent H2O2 production and subsequent activation of MPK1/2 play an important role in acclimation-induced cross-tolerance in tomato.
J. Exp. Bot.
PUBLISHED: 12-09-2013
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H2O2 and mitogen-activated protein kinase (MAPK) cascades play important functions in plant stress responses, but their roles in acclimation response remain unclear. This study examined the functions of H2O2 and MPK1/2 in acclimation-induced cross-tolerance in tomato plants. Mild cold, paraquat, and drought as acclimation stimuli enhanced tolerance to more severe subsequent chilling, photooxidative, and drought stresses. Acclimation-induced cross-tolerance was associated with increased transcript levels of RBOH1 and stress- and defence-related genes, elevated apoplastic H2O2 accumulation, increased activity of NADPH oxidase and antioxidant enzymes, reduced glutathione redox state, and activation of MPK1/2 in tomato. Virus-induced gene silencing of RBOH1, MPK1, and MPK2 or MPK1/2 all compromised acclimation-induced cross-tolerance and associated stress responses. Taken together, these results strongly suggest that acclimation-induced cross-tolerance is largely attributed to RBOH1-dependent H2O2 production at the apoplast, which may subsequently activate MPK1/2 to induce stress responses.
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A brief analysis of traditional chinese medical elongated needle therapy on acute spinal cord injury and its mechanism.
Evid Based Complement Alternat Med
PUBLISHED: 09-26-2013
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Acute spinal cord injury is one of the most common and complicated diseases among human spinal injury. We aimed to explore the effect of point-through-point acupuncture therapy with elongated needles on acute spinal cord injury in rabbits and its possible mechanism. Adult rabbits were randomly divided into a model group, elongated needle therapy group, and blank group. Immunohistochemical staining showed that the protein levels of Fas and caspase-3 in the model group were significantly higher than those in the blank group at each time point (P < 0.05) and significantly lower than those in the elongated needle therapy group on the 3rd and 5th days after operation (P < 0.05). RT-PCR showed that Fas and caspase-3 mRNA levels in the model group and elongated needle therapy group were significantly higher than those in the blank group (P < 0.05, 0.01). The mRNA levels of Fas and caspase-3 in the elongated needle therapy group were significantly lower than those in model group on the 3rd day (P < 0.05, 0.01). Therefore, we confirmed that elongated needle therapy has an obvious effect on acute spinal cord injury in rabbits. Its mechanism is made possible by inhibiting the expression of the Fas?caspase-3 cascade, thereby inhibiting cell apoptosis after spinal cord injury.
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[Realization of DICOM medical image compression technology].
Zhongguo Yi Liao Qi Xie Za Zhi
PUBLISHED: 09-11-2013
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This paper introduces the implement method of DICOM medical image compression technology, The image part of DICOM files are extracted and converted to BMP format. The non-image information in DICOM file are stored into the text. When the final image of JPEG standard and non-image information are encapsulated to DICOM format images, it realizes the compression of medical image, which is beneficial to the image storage and transmission.
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Anti-angiogenic and anti-tumoral effects mediated by a VEGFR1 targeted DNAzyme.
Mol. Med.
PUBLISHED: 08-14-2013
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Anti-angiogenesis is a promising antitumor strategy that inhibits tumor vascular formation to suppress tumor growth. DNAzymes are synthetic single-strand DNA molecules that can cleave RNAs. Here, we conducted a comprehensive in vitro selection of active DNAzymes for their activity to cleave the vascular endothelial growth factor receptor (VEGFR-1) mRNA and screened for their biological activity in a matrigel tube-formation assay. Among the selected DNAzymes, DT18 was defined as a lead molecule that was further investigated in several model systems. In a rat corneal vascularization model, DT18 demonstrated significant and specific antiangiogenic activity as evidenced by the reduced area and vessel number in VEGF-induced corneal angiogenesis. In a mouse melanoma model, DT18 was shown to inhibit B16 tumor growth, while it did not affect B16 cell proliferation. We further assessed DT18 effect in mice with established human nasopharyngeal carcinoma (NPC). A significant inhibition of tumor growth was observed, which accompanied with down-regulation of VEGFR-1 expression in NPC tumor tissues. To evaluate DT18 effect on vasculature, we performed DCE-MRI on the human NPC xenograft mice treated with DT18 and showed a markedly reduction of the parameter of K(trans) that reflects the condition of tumor microvascular permeability. In examination of the safety and tolerability of DT18, intravenous Dz18 administration to healthy mice caused no substantial toxicities, as shown by parameters that included body weight, liver/kidney function, and histological and biochemical analyses. Taken together, our data suggest that the anti-VEGFR1 DNAzyme may be used as a therapeutic agent for the treatment of cancer, such as NPC.
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[Molluscicidal effect of buried niclosamide sustained-release method in plateau mountainous areas].
Zhongguo Xue Xi Chong Bing Fang Zhi Za Zhi
PUBLISHED: 07-31-2013
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To evaluate the molluscicidal effect of the buried niclosamide sustained-release method in Oncomelania snail-infested terraced environments of mountainous areas in Yunnan Province.
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Therapeutic Evaluation of Epstein-Barr Virus-encoded Latent Membrane Protein-1 Targeted DNAzyme for Treating of Nasopharyngeal Carcinomas.
Mol. Ther.
PUBLISHED: 07-23-2013
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The ability of the 10-23 DNAzyme to specifically cleave RNA with high efficiency has fuelled expectation that this agent may have useful applications for targeted therapy. Here, we, for the first time, investigated the antitumor and radiosensitizing effects of a DNAzyme (DZ1) targeted to the Epstein-Barr virus (EBV)-LMP1 mRNA of nasopharyngeal carcinoma (NPC) in patients. Preclinical studies indicated that the DNAzyme was safe and well tolerated. A randomized and double-blind clinical study was conducted in 40 NPC patients who received DZ1 or saline intratumorally, in conjunction with radiation therapy. Tumor regression, patient survival, EBV DNA copy number and tumor microvascular permeability were assessed in a 3-month follow-up. The mean tumor regression rate at week 12 was significantly higher in DZ1 treated group than in the saline control group. Molecular imaging analysis showed that DZ1 impacted on tumor microvascular permeability as evidenced by a faster decline of the K(trans) in DZ1-treated patients. The percentage of the samples with undetectable level of EBV DNA copy in the DZ1 group was significantly higher than that in the control group. No adverse events that could be attributed to the DZ1 injection were observed in patients.Molecular Therapy (2013); doi:10.1038/mt.2013.257.
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The rapidly expanding CRF01_AE epidemic in China is driven by multiple lineages of HIV-1 viruses introduced in the 1990s.
AIDS
PUBLISHED: 06-29-2013
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We sought to comprehensively analyze the origin, transmission patterns and sub-epidemic clusters of the HIV-1 CRF01_AE strains in China.
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Acupuncture and moxibustion for cancer-related fatigue: a systematic review and meta-analysis.
Asian Pac. J. Cancer Prev.
PUBLISHED: 06-28-2013
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Faced with highly prevalent and recalcitrant cancer-related fatigue (CRF), together with the absence of any official guidelines on management, numerous groups have been striving to seek and test alternative therapies including acupuncture and moxibustion. However, different patients have various feedbacks, and the many clinical trials have given rise to varied conclusions. In terms of the therapeutic effect of acupuncture and moxibustion, there exist vast inconsistencies. Objective: The aim of the study was to evaluate the auxiliary effectiveness of acupuncture and moxibustion in the treatment of CRF, and to provide more reliable evidence to guide clinical practice.
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[Treatment of pediatric critical trauma following earthquake disasters].
Zhongguo Dang Dai Er Ke Za Zhi
PUBLISHED: 06-25-2013
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Children are the most vulnerable in natural disasters for their poor self-protection ability. Pediatric deaths in earthquakes are mainly due to cardiopulmonary arrest, severe craniocerebral injury, shock, crush syndrome, and multiple organ failure. Priority should be given to centralized, effective treatment for injured children, with multidisciplinary cooperation, and severe cases need to be transferred to the pediatric intensive care unit, thus improving survival and reducing disability.
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[A(H5N1) and A(H7N9) avian influenza: the H7N9 avian influenza outbreak of 2013].
Zhongguo Dang Dai Er Ke Za Zhi
PUBLISHED: 06-25-2013
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influenza virus can infect humans and cause disease. The clinical presentation of human infection is usually mild, but the infection caused by A(H5N1) avian influenza virus occurring initially in Hongkong in 1997 or the A(H7N9) virus isolated first at the beginning of this year in China is severe and characterized by high mortality. The mortality rate of adolescents and children caused by H5N1 avian influenza is lower than that of adults and the younger the child the lower the mortality rate. A few pediatric H7N9 avian influenza cases recovered soon after treatment. A child was determined to be a H7N9 avian influenza virus carrier. These findings suggested that the pediatric H7N9 avian influenza infection was mild. It is very important to start anti-virus treatment with oseltamivir as early as possible in cases of avian influenza infection is considered. Combined therapy, including respiratory and circulatory support and inhibiting immunological reaction, is emphasized in the treatment of severe cases.
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Molecular mechanisms and treatment of radiation-induced lung fibrosis.
Curr Drug Targets
PUBLISHED: 06-19-2013
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Radiation-induced lung fibrosis (RILF) is a severe side effect of radiotherapy in lung cancer patients that presents as a progressive pulmonary injury combined with chronic inflammation and exaggerated organ repair. RILF is a major barrier to improving the cure rate and well-being of lung cancer patients because it limits the radiation dose that is required to effectively kill tumor cells and diminishes normal lung function. Although the exact mechanism is unclear, accumulating evidence suggests that various cells, cytokines and regulatory molecules are involved in the tissue reorganization and immune response modulation that occur in RILF. In this review, we will summarize the general symptoms, diagnostics, and current understanding of the cells and molecular factors that are linked to the signaling networks implicated in RILF. Potential approaches for the treatment of RILF will also be discussed. Elucidating the key molecular mediators that initiate and control the extent of RILF in response to therapeutic radiation may reveal additional targets for RILF treatment to significantly improve the efficacy of radiotherapy for lung cancer patients.
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Single-molecule spectroscopy reveals photosynthetic LH2 complexes switch between emissive states.
Proc. Natl. Acad. Sci. U.S.A.
PUBLISHED: 06-17-2013
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Photosynthetic organisms flourish under low light intensities by converting photoenergy to chemical energy with near unity quantum efficiency and under high light intensities by safely dissipating excess photoenergy and deleterious photoproducts. The molecular mechanisms balancing these two functions remain incompletely described. One critical barrier to characterizing the mechanisms responsible for these processes is that they occur within proteins whose excited-state properties vary drastically among individual proteins and even within a single protein over time. In ensemble measurements, these excited-state properties appear only as the average value. To overcome this averaging, we investigate the purple bacterial antenna protein light harvesting complex 2 (LH2) from Rhodopseudomonas acidophila at the single-protein level. We use a room-temperature, single-molecule technique, the anti-Brownian electrokinetic trap, to study LH2 in a solution-phase (nonperturbative) environment. By performing simultaneous measurements of fluorescence intensity, lifetime, and spectra of single LH2 complexes, we identify three distinct states and observe transitions occurring among them on a timescale of seconds. Our results reveal that LH2 complexes undergo photoactivated switching to a quenched state, likely by a conformational change, and thermally revert to the ground state. This is a previously unobserved, reversible quenching pathway, and is one mechanism through which photosynthetic organisms can adapt to changes in light intensities.
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Pancreatic Duct Stents at Pancreaticoduodenectomy: A Meta-Analysis.
Dig Surg
PUBLISHED: 06-13-2013
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Background and Objective: Several studies suggested that pancreatic stents had some benefit during pancreatoduodenectomy (PD), but others disagree. Whether pancreatic duct stents could prevent postoperative pancreatic fistula (POPF) is still under controversy. Methods: Randomized controlled trials published before November 2012 were all aggregated, focusing on the evaluation of pancreatic duct stents during PD. Trial data was reviewed and extracted independently by two reviewers. The quality of the including studies was assessed by the Cochrane handbook 5.1.0. Results: Seven studies were included, with a total of 793 patients. The results showed that compared with nonstents, stents during PD was associated with a significant difference on overall POPF rate (OR = 0.65, 95% CI 0.45-0.95, p = 0.02), POPF grades B and C (OR = 0.45, 95% CI 0.27-0.76, p = 0.003), and hospital stay (MD = -4.28, 95% CI -6.81, -1.75, p = 0.0009). Subgroup analyses showed that the external stent had a significant difference in the incidence of overall POPF (OR = 0.46, 95% CI 0.29-0.73, p = 0.0009), POPF grades B and C (OR = 0.49, 95% CI 0.30-0.79, p = 0.003), postoperative morbidity (OR = 0.63, 95% CI 0.42-0.96, p = 0.03), as well as hospital stay. Conclusions: Based upon this meta-analysis, there might be potential benefit in reducing POPF thanks to the use of pancreatic duct stents. © 2013 S. Karger AG, Basel.
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Stress transfer of a Kevlar 49 fiber pullout test studied by micro-Raman spectroscopy.
Appl Spectrosc
PUBLISHED: 06-06-2013
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The interfacial stress transfer behavior of a Kevlar 49 aramid fiber-epoxy matrix was studied with fiber pullout tests, the fibers of which were stretched by a homemade microloading device. Raman spectra on the embedded fiber were recorded by micro-Raman spectroscopy, under different strain levels. Then, the fiber axial stress was obtained by the relationship between the stress and Raman shift of the aramid fiber. Experimental results revealed that the fiber axial stress increased significantly with the load. The shear stress concentration occurred at the fiber entry to the epoxy resin. Thus, interfacial friction stages exist in the debonded fiber segment, and the interfacial friction shear stress is constant within one stage. The experimental results are consistent with the theoretical model predictions.
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A novel chemiluminescent ELISA for detecting furaltadone metabolite, 3-amino-5-morpholinomethyl-2-oxazolidone (AMOZ) in fish, egg, honey and shrimp samples.
J. Immunol. Methods
PUBLISHED: 05-23-2013
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In this study, an indirect competitive enzyme-linked immunosorbent assay with chemiluminescent (CLELISA) detection for 3-amino-5-morpholinomethyl-2-oxazolidone (AMOZ) was developed. A monoclonal antibody (MAb) against AMOZ was prepared through immunizing BALB/c mice with 4-carboxybenzaldehyle derivatized AMOZ (CPAMOZ), conjugated with bovine serum albumin (BSA) as antigen. The effects of the substrates luminol, p-iodophenol and urea peroxide on the performance of the assay were studied and optimized. In addition, the specificity of the MAb, estimated as the cross-reactivity values with 4-nitrobenzaldehyde derivatized AMOZ (NPAMOZ), CPAMOZ and AMOZ, was 100%, 27.45% and 0.18%, respectively. The sensitivity of the developed CLELISA was estimated as 50% inhibitory concentration (IC50) value (0.14?g/l) with a linear working range between 0.03 and 64?g/l, and a limit of detection of 0.01?g/l. The CLELISA described in this study was 5-fold more sensitive than the indirect competitive ELISA previously developed in our laboratory. Finally, this new CLELISA was compared with a commercial kit to detect NPAMOZ in spiked fish, shrimp, honey and egg samples. The recovery values from four spiked fish, shrimp, honey and egg samples with different concentrations of NPAMOZ in CLELISA were 92.1-107.7%. Thus, the immunoassay method described here has a broad detection range and high sensitivity and is a valid and cost-effective means for high throughput monitoring of residual AMOZ levels in fish, shrimps, honey and eggs with potential applications in other animal tissues.
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Structure and gene cluster of the O-antigen of Escherichia coli O154.
Carbohydr. Res.
PUBLISHED: 04-25-2013
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The O-polysaccharide (O-antigen) of Escherichia coli O154 was studied by sugar analysis along with 1D and 2D (1)H and (13)C NMR spectroscopy. The following structure of the branched pentasaccharide repeating unit was established: [structure: see text]. The O-antigen gene cluster of E. coli O154 was sequenced. The gene functions were tentatively assigned by comparison with sequences in the available databases and found to be in full agreement with the O-polysaccharide structure.
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The association of TP53 mutations with the resistance of colorectal carcinoma to the insulin-like growth factor-1 receptor inhibitor picropodophyllin.
BMC Cancer
PUBLISHED: 04-24-2013
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There is growing evidence indicating the insulin-like growth factor 1 receptor (IGF-1R) plays a critical role in the progression of human colorectal carcinomas. IGF-1R is an attractive drug target for the treatment of colon cancer. Picropodophyllin (PPP), of the cyclolignan family, has recently been identified as an IGF-1R inhibitor. The aim of this study is to determine the therapeutic response and mechanism after colorectal carcinoma treatment with PPP.
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Volatile fatty acids production from food waste: effects of pH, temperature, and organic loading rate.
Bioresour. Technol.
PUBLISHED: 04-08-2013
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The effects of pH, temperature, and organic loading rate (OLR) on the acidogenesis of food waste have been determined. The present study investigated their effects on soluble chemical oxygen demand (SCOD), volatile fatty acids (VFAs), volatile solids (VS), and ammonia nitrogen (NH4(+)-N). Both the concentration and yield of VFAs were highest at pH 6.0, acetate and butyrate accounted for 77% of total VFAs. VFAs concentration and the VFA/SCOD ratio were highest, and VS levels were lowest, at 45 °C, but the differences compared to the values at 35 °C were slight. The concentrations of VFAs, SCOD, and NH4(+)-N increased as OLR increased, whereas the yield of VFAs decreased from 0.504 at 5 g/Ld to 0.306 at 16 g/Ld. Acetate and butyrate accounted for 60% of total VFAs. The percentage of acetate and valerate increased as OLR increased, whereas a high OLR produced a lower percentage of propionate and butyrate.
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Bunyamwera virus possesses a distinct nucleocapsid protein to facilitate genome encapsidation.
Proc. Natl. Acad. Sci. U.S.A.
PUBLISHED: 04-08-2013
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Bunyamwera virus (BUNV), which belongs to the genus Orthobunyavirus, is the prototypical virus of the Bunyaviridae family. Similar to other negative-sense single-stranded RNA viruses, bunyaviruses possess a nucleocapsid protein (NP) to facilitate genomic RNA encapsidation and virus replication. The structures of two NPs of members of different genera within the Bunyaviridae family have been reported. However, their structures, RNA-binding features, and functions beyond RNA binding significantly differ from one another. Here, we report the crystal structure of the BUNV NP-RNA complex. The polypeptide of the BUNV NP was found to possess a distinct fold among viral NPs. An N-terminal arm and a C-terminal tail were found to interact with neighboring NP protomers to form a tetrameric ring-shaped organization. Each protomer bound a 10-nt RNA molecule, which was acquired from the expression host, in the positively charged crevice between the N and C lobes. Inhomogeneous oligomerization was observed for the recombinant BUNV NP-RNA complex, which was similar to the Rift Valley fever virus NP-RNA complex. This result suggested that the flexibility of one NP protomer with adjacent protomers underlies the BUNV ribonucleoprotein complex (RNP) formation. Electron microscopy revealed that the monomer-sized NP-RNA complex was the building block of the natural BUNV RNP. Combined with previous results indicating that mutagenesis of the interprotomer or protein-RNA interface affects BUNV replication, our structure provides a great potential for understanding the mechanism underlying negative-sense single-stranded RNA RNP formation and enables the development of antiviral therapies targeting BUNV RNP formation.
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Protein-protein interactions in the regulation of WRKY transcription factors.
Mol Plant
PUBLISHED: 03-02-2013
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It has been almost 20 years since the first report of a WRKY transcription factor, SPF1, from sweet potato. Great progress has been made since then in establishing the diverse biological roles of WRKY transcription factors in plant growth, development, and responses to biotic and abiotic stress. Despite the functional diversity, almost all analyzed WRKY proteins recognize the TTGACC/T W-box sequences and, therefore, mechanisms other than mere recognition of the core W-box promoter elements are necessary to achieve the regulatory specificity of WRKY transcription factors. Research over the past several years has revealed that WRKY transcription factors physically interact with a wide range of proteins with roles in signaling, transcription, and chromatin remodeling. Studies of WRKY-interacting proteins have provided important insights into the regulation and mode of action of members of the important family of transcription factors. It has also emerged that the slightly varied WRKY domains and other protein motifs conserved within each of the seven WRKY subfamilies participate in protein-protein interactions and mediate complex functional interactions between WRKY proteins and between WRKY and other regulatory proteins in the modulation of important biological processes. In this review, we summarize studies of protein-protein interactions for WRKY transcription factors and discuss how the interacting partners contribute, at different levels, to the establishment of the complex regulatory and functional network of WRKY transcription factors.
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Structure and gene cluster of the O-antigen of Escherichia coli O76.
Carbohydr. Res.
PUBLISHED: 02-12-2013
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The O-polysaccharide (O-antigen) of Escherichia coli O76 was studied by sugar analysis along with 1D and 2D (1)H,(13)C NMR spectroscopies. The following structure of the linear tetrasaccharide repeating unit was established: ?4)-?-D-GlcpA-(1?4)-?-D-GalpNAc3Ac-(1?4)-?-D-GalpNAc-(1?3)-?-D-GalpNAc-(1?. The degree of O-acetylation of 4-substituted ?-GalNAc residue is ~70%. The O-antigen gene cluster of E. coli O76 was sequenced. The functions of genes in the O-antigen gene cluster were tentatively assigned by comparison with sequences in the available databases and found to be in full agreement with the E. coli O76 O-antigen structure.
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Design, synthesis and evaluation of 1,2-benzisothiazol-3-one derivatives as potent caspase-3 inhibitors.
Bioorg. Med. Chem.
PUBLISHED: 02-01-2013
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A number of 1,2-benzisothiazol-3-one derivatives were prepared through structural modification of the original compound from high-throughput screening. Some analogues (e.g., 6b, 6r, 6s and 6w) were identified as novel and potent caspase inhibitors with IC50 of nanomolar. Structure-activity relationship (SAR) studies for caspase-3 inhibition were evaluated in vitro. Molecular modeling studies provided further insight into the interaction of this class of compounds with activated caspase-3. The present small molecule caspase-3 inhibitor with novel structures different from structures of known caspase inhibitors revealed a new direction for therapeutic strategies directed against diseases involving abnormally up-regulated apoptosis.
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Activation of NF-?B and respiratory burst following Aspergillus fumigatus stimulation of macrophages.
Immunobiology
PUBLISHED: 01-23-2013
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Dectin-2, a C-type lectin receptor (CLR), plays an essential role in mediating nuclear factor-kappa B (NF-?B) activation and anti-fungal immunity in response to Candida albicans infection. However, the molecular mechanisms and function of Dectin-2 signaling in response to infection by the pathogenic fungus Aspergillus fumigatus have not been characterized. In order to characterize Dectin-2 signaling in response to A. fumigatus infection, activation of Dectin-2 was analyzed at both transcriptional and translational levels. Spleen tyrosine kinase (Syk) phosphorylation, NF-?B activation and cytokine production downstream of Dectin-2 activation were also investigated. In addition, Dectin-2-Syk function and its ability to mediate reactive oxygen species (ROS) production and elimination of A. fumigatus conidia was examined. We demonstrate that Syk is involved in Dectin-2-induced I?B? (inhibitor of kappa B protein) phosphorylation and NF-?B activation following A. fumigatus stimulation in a time dependent manner. Silencing of Dectin-2 and Syk as well as Syk inhibition blocks NF-?B activation and cytokine secretion. Furthermore, the killing of A. fumigatus conidia and ROS production are significantly affected by Dectin-2 or Syk silencing as well as Syk inhibition. Swelling and germination of the fungus followed by hyphae formation and not the resting and heat-inactivated form of A. fumigatus mediate the activation of Dectin-2 signaling. In conclusion, Syk plays an essential role in I?B? kinase phosphorylation, NF-?B activation, and ROS production mediated by Dectin-2 activation in response to A. fumigatus infection.
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NBR1-mediated selective autophagy targets insoluble ubiquitinated protein aggregates in plant stress responses.
PLoS Genet.
PUBLISHED: 01-17-2013
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Plant autophagy plays an important role in delaying senescence, nutrient recycling, and stress responses. Functional analysis of plant autophagy has almost exclusively focused on the proteins required for the core process of autophagosome assembly, but little is known about the proteins involved in other important processes of autophagy, including autophagy cargo recognition and sequestration. In this study, we report functional genetic analysis of Arabidopsis NBR1, a homolog of mammalian autophagy cargo adaptors P62 and NBR1. We isolated two nbr1 knockout mutants and discovered that they displayed some but not all of the phenotypes of autophagy-deficient atg5 and atg7 mutants. Like ATG5 and ATG7, NBR1 is important for plant tolerance to heat, oxidative, salt, and drought stresses. The role of NBR1 in plant tolerance to these abiotic stresses is dependent on its interaction with ATG8. Unlike ATG5 and ATG7, however, NBR1 is dispensable in age- and darkness-induced senescence and in resistance to a necrotrophic pathogen. A selective role of NBR1 in plant responses to specific abiotic stresses suggest that plant autophagy in diverse biological processes operates through multiple cargo recognition and delivery systems. The compromised heat tolerance of atg5, atg7, and nbr1 mutants was associated with increased accumulation of insoluble, detergent-resistant proteins that were highly ubiquitinated under heat stress. NBR1, which contains an ubiquitin-binding domain, also accumulated to high levels with an increasing enrichment in the insoluble protein fraction in the autophagy-deficient mutants under heat stress. These results suggest that NBR1-mediated autophagy targets ubiquitinated protein aggregates most likely derived from denatured or otherwise damaged nonnative proteins generated under stress conditions.
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Plant-soil feedbacks and soil sickness: from mechanisms to application in agriculture.
J. Chem. Ecol.
PUBLISHED: 01-15-2013
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Negative plant-soil feedbacks play an important role in soil sickness, which is one of the factors limiting the sustainable development of intensive agriculture. Various factors, such as the buildup of pests in the soil, disorder in physico-chemical soil properties, autotoxicity, and other unknown factors may contribute to soil sickness. A range of autotoxins have been identified, and these exhibit their allelopathic potential by influencing cell division, water and ion uptake, dark respiration, ATP synthesis, redox homeostasis, gene expression, and defense responses. Meanwhile, there are great interspecific and intraspecific differences in the uptake and accumulation of autotoxins, which contribute to the specific differences in growth in response to different autotoxins. Importantly, the autotoxins also influence soil microbes and vice versa, leading to an increased or decreased degree of soil sickness. In many cases, autotoxins may enhance soilborne diseases by predisposing the roots to infection by soilborne pathogens through a direct biochemical and physiological effect. Some approaches, such as screening for low autotoxic potential and disease-resistant genotypes, proper rotation and intercropping, proper soil and plant residue management, adoption of resistant plant species as rootstocks, introduction of beneficial microbes, physical removal of phytotoxins, and soil sterilization, are proposed. We discuss the challenges that we are facing and possible approaches to these.
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Results of operative treatment of avulsion fractures of the iliac crest apophysis in adolescents.
Injury
PUBLISHED: 01-08-2013
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Avulsion fracture of the iliac crest apophysis is a rare condition that commonly occurs in adolescent athletes. Conservative treatment for this injury can produce excellent functional outcomes. However, the rehabilitation process requires a rather long immobilisation period. This study aimed to evaluate the use of cannulated screws for fixation of avulsion fractures of iliac crest apophysis.
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JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

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