3,450 research outputs found

    Investigation of the Antiasthmatic Properties of Ethanol Extract of Callophyllis japonica in Mice

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    Purpose: To determine whether an ethanol extract from Callophyllis japonica (C. japonica) could attenuate indices of airway inflammation in a murine model of ovalbumin (OVA)-induced asthma.Methods: The free radical scavenging activity of the C. japonica ethanol extracts (CJE) were investigated using an electron spin resonance (ESR) system. To make develop animal model of asthma, mice were sensitized and challenged with OVA.Results: CJE exhibited considerable scavenging activity of 71.08 ± 0.73, 79.11 ± 6.04%, 75.95 ± 7.01%, and 48.56 ± 5.96% of DPPH, alkyl, superoxide, and hydroxyl radicals, respectively. The successive intraperitoneal administration of CJE reduced the number of eosinophils in bronchoalveolar lavage (BAL) fluid, development of airway hyperresponsiveness (AHR), an increase in pulmonary Th2 cytokines, and allergen-specific immunoglobulin E (IgE).Conclusion: Administration of CJE markedly alleviates all indices of airway inflammation. This study provides evidence that CJE plays a critical role in the amelioration of the pathogenetic process of allergic asthma in mice.Keywords: Asthma, Phenolic contents, Free radical scavenging, Airway hyper-responsiveness, Cytokines, Immunoglobulin

    Osteopontin as potential biomarker and therapeutic target in gastric and liver cancers

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    Single particle analysis: Methods for detection of platelet extracellular vesicles in suspension (excluding flow cytometry)

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    Extracellular vesicles (EVs) are small, membrane-bound particles released by all cell types, including abundant release by platelets. EVs are a topic of increasing interest in the academic and clinical community due to their increasingly recognised and diverse role in normal biology as well as in disease. However, typical analysis methods to characterise EVs released by cultured cells or isolated from whole blood or other body fluids are restricted to bulk analysis of all EVs in a sample. In this review, we discuss the motivation for analysis of individual EVs, as well as discuss three emerging methods for physical and chemical characterisation of individual EVs: nanoparticle tracking analysis, tunable resistive pulse sensing and Raman spectroscopy. We give brief descriptions of the working principles of each technique, along with a review noting the benefits and limitations of each method as applied to detection of single EVs

    Elastic modulus of muscle and tendon with shear wave ultrasound elastography : variations with different technical settings

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    Author name used in this publication: Brian Chin Wing KotVersion of RecordPublishe

    Design, synthesis and biological characterization of novel inhibitors of CD38

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    Human CD38 is a novel multi-functional protein that acts not only as an antigen for B-lymphocyte activation, but also as an enzyme catalyzing the synthesis of a Ca 2+ messenger molecule, cyclic ADP-ribose, from NAD +. It is well established that this novel Ca 2+ signaling enzyme is responsible for regulating a wide range of physiological functions. Based on the crystal structure of the CD38/NAD + complex, we synthesized a series of simplified N-substituted nicotinamide derivatives (Compound1-14). A number of these compounds exhibited moderate inhibition of the NAD + utilizing activity of CD38, with Compound4 showing the highest potency. The crystal structure of CD38/Compound4 complex and computer simulation of Compound7 docking to CD38 show a significant role of the nicotinamide moiety and the distal aromatic group of the compounds for substrate recognition by the active site of CD38. Biologically, we showed that both Compounds4 and 7 effectively relaxed the agonist-induced contraction of muscle preparations from rats and guinea pigs. This study is a rational design of inhibitors for CD38 that exhibit important physiological effects, and can serve as a model for future drug development. © 2011 The Royal Society of Chemistry.postprin

    Apparent temperature and acute myocardial infarction hospital admissions in Copenhagen, Denmark: a case-crossover study

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    <p>Abstract</p> <p>Background</p> <p>The influence of temperature on acute myocardial infarction (AMI) has not been investigated as extensively as the effects of broader outcomes of morbidity and mortality. Sixteen studies reported inconsistent results and two considered confounding by air pollution. We addressed some of the methodological limitations of the previous studies in this study.</p> <p>Methods</p> <p>This is the first study of the association between the daily 3-hour maximum apparent temperature (Tapp<sub>max</sub>) and AMI hospital admissions in Copenhagen. The study period covered 1 January 1999-31 December 2006, stratified in warm (April - September) and cold (October - March) periods. A case-crossover epidemiology study design was applied. Models were adjusted for public holidays and influenza, confounding by PM<sub>10</sub>, NO<sub>2 </sub>and CO was investigated, the lag and non-linear effects of Tapp<sub>max </sub>was examined, effect modification by age, sex and SES was explored, and the results of the case-crossover models were compared to those of the generalised additive Poisson time-series and generalised estimating equation models.</p> <p>Results</p> <p>14 456 AMI hospital admissions (12 995 people) occurred during the study period. For an inter-quartile range (6 or 7°C) increase in the 5-day cumulative average of Tapp<sub>max</sub>, a 4% (95% CI:-2%; 10%) and 9% (95% CI: 3%; 14%) decrease in the AMI admission rate was observed in the warm and cold periods, respectively. The 19-65 year old group, men and highest SES group seemed to be more susceptible in the cold period.</p> <p>Conclusion</p> <p>An increase in Tapp<sub>max </sub>is associated with a decrease in AMI admissions during the colder months.</p

    A survey of performance enhancement of transmission control protocol (TCP) in wireless ad hoc networks

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    This Article is provided by the Brunel Open Access Publishing Fund - Copyright @ 2011 Springer OpenTransmission control protocol (TCP), which provides reliable end-to-end data delivery, performs well in traditional wired network environments, while in wireless ad hoc networks, it does not perform well. Compared to wired networks, wireless ad hoc networks have some specific characteristics such as node mobility and a shared medium. Owing to these specific characteristics of wireless ad hoc networks, TCP faces particular problems with, for example, route failure, channel contention and high bit error rates. These factors are responsible for the performance degradation of TCP in wireless ad hoc networks. The research community has produced a wide range of proposals to improve the performance of TCP in wireless ad hoc networks. This article presents a survey of these proposals (approaches). A classification of TCP improvement proposals for wireless ad hoc networks is presented, which makes it easy to compare the proposals falling under the same category. Tables which summarize the approaches for quick overview are provided. Possible directions for further improvements in this area are suggested in the conclusions. The aim of the article is to enable the reader to quickly acquire an overview of the state of TCP in wireless ad hoc networks.This study is partly funded by Kohat University of Science & Technology (KUST), Pakistan, and the Higher Education Commission, Pakistan

    Preconditioning of mesenchymal stromal cells with low-intensity ultrasound: influence on chondrogenesis and directed SOX9 signaling pathways

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    Background: Continuous low-intensity ultrasound (cLIUS) facilitates the chondrogenic differentiation of human mesenchymal stromal cells (MSCs) in the absence of exogenously added transforming growth factor-beta (TGFβ) by upregulating the expression of transcription factor SOX9, a master regulator of chondrogenesis. The present study evaluated the molecular events associated with the signaling pathways impacting SOX9 gene and protein expression under cLIUS. Methods: Human bone marrow-derived MSCs were exposed to cLIUS stimulation at 14 kPa (5 MHz, 2.5 Vpp) for 5 min. The gene and protein expression of SOX9 was evaluated. The specificity of SOX9 upregulation under cLIUS was determined by treating the MSCs with small molecule inhibitors of select signaling molecules, followed by cLIUS treatment. Signaling events regulating SOX9 expression under cLIUS were analyzed by gene expression, immunofluorescence staining, and western blotting. Results: cLIUS upregulated the gene expression of SOX9 and enhanced the nuclear localization of SOX9 protein when compared to non-cLIUS-stimulated control. cLIUS was noted to enhance the phosphorylation of the signaling molecule ERK1/2. Inhibition of MEK/ERK1/2 by PD98059 resulted in the effective abrogation of cLIUS-induced SOX9 expression, indicating that cLIUS-induced SOX9 upregulation was dependent on the phosphorylation of ERK1/2. Inhibition of integrin and TRPV4, the upstream cell-surface effectors of ERK1/2, did not inhibit the phosphorylation of ERK1/2 and therefore did not abrogate cLIUS-induced SOX9 expression, thereby suggesting the involvement of other mechanoreceptors. Consequently, the effect of cLIUS on the actin cytoskeleton, a mechanosensitive receptor regulating SOX9, was evaluated. Diffused and disrupted actin fibers observed in MSCs under cLIUS closely resembled actin disruption by treatment with cytoskeletal drug Y27632, which is known to increase the gene expression of SOX9. The upregulation of SOX9 under cLIUS was, therefore, related to cLIUS-induced actin reorganization. SOX9 upregulation induced by actin reorganization was also found to be dependent on the phosphorylation of ERK1/2. Conclusions: Collectively, preconditioning of MSCs by cLIUS resulted in the nuclear localization of SOX9, phosphorylation of ERK1/2 and disruption of actin filaments, and the expression of SOX9 was dependent on the phosphorylation of ERK1/2 under cLIUS

    Analysis of Gene Expression in Resynthesized Brassica napus Allopolyploids Using Arabidopsis 70mer Oligo Microarrays

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    Background Studies in resynthesized Brassica napus allopolyploids indicate that homoeologous chromosome exchanges in advanced generations (S5:6) alter gene expression through the loss and doubling of homoeologous genes within the rearrangements. Rearrangements may also indirectly affect global gene expression if homoeologous copies of gene regulators within rearrangements have differential affects on the transcription of genes in networks. Methodology/Principal Findings We utilized Arabidopsis 70mer oligonucleotide microarrays for exploring gene expression in three resynthesized B. napus lineages at the S0:1 and S5:6 generations as well as their diploid progenitors B. rapa and B. oleracea. Differential gene expression between the progenitors and additive (midparent) expression in the allopolyploids were tested. The S5:6 lines differed in the number of genetic rearrangements, allowing us to test if the number of genes displaying nonadditive expression was related to the number of rearrangements. Estimates using per-gene and common variance ANOVA models indicated that 6–15% of 26,107 genes were differentially expressed between the progenitors. Individual allopolyploids showed nonadditive expression for 1.6–32% of all genes. Less than 0.3% of genes displayed nonadditive expression in all S0:1lines and 0.1–0.2% were nonadditive among all S5:6 lines. Differentially expressed genes in the polyploids were over-represented by genes differential between the progenitors. The total number of differentially expressed genes was correlated with the number of genetic changes in S5:6 lines under the common variance model; however, there was no relationship using a per-gene variance model, and many genes showed nonadditive expression in S0:1 lines. Conclusions/Significance Few genes reproducibly demonstrated nonadditive expression among lineages, suggesting few changes resulted from a general response to polyploidization. Furthermore, our microarray analysis did not provide strong evidence that homoeologous rearrangements were a determinant of genome-wide nonadditive gene expression. In light of the inherent limitations of the Arabidopsis microarray to measure gene expression in polyploid Brassicas, further studies are warranted
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