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991.
Nuno Bernardes Ana Sofia Ribeiro Sofia Abreu Bruna Mota Rute G. Matos Cecilia M. Arraiano Raquel Seruca Joana Paredes Arsenio M. Fialho 《PloS one》2013,8(7)
P-cadherin overexpression occurs in about 30% of all breast carcinomas, being a poor prognostic factor for breast cancer patients. In a cellular background of wild-type E-cadherin, we have previously shown that its expression promotes invasion, motility and migration of breast cancer cells due to the induced secretion of metalloproteases (MMPs) to the extracellular medium and to the concomitant shedding of a pro-invasive soluble form of this protein (sP-cad). Azurin is secreted by Pseudomonas aeruginosa and induces in vitro and in vivo cytotoxicity after its preferential penetration in human cancer cells relative to normal cells. Three different breast cancer cell lines, MCF-7/AZ.Mock, MCF-7/AZ.Pcad and SUM149 were treated with sub-killing doses of azurin. Invasion of these cells was measured using Matrigel Invasion Assays and MTT assays were performed to determine cell viability upon treatment and the effects on cadherins expression was determined by Western blot and Immunofluorescence. Gelatin Zymography was used to determine activity of MMP2 in the conditioned media of azurin treated and untreated cells and the phosphorylation levels of intracellular signaling proteins were determined by Western blot. The invasive phenotype of these breast cancer cells was significantly reduced by azurin. Azurin (50–100 µM) also caused a specific decrease on P-cadherin protein levels from 30–50% in MCF-7/AZ.Pcad and SUM149 breast cancer cell lines, but the levels of E-cadherin remain unaltered. More, the levels of sP-cad and the activity of MMP2 were reduced in the extracellular media of azurin treated cells and we also observed a decrease in the phosphorylation levels of both FAK and Src proteins. Our data show that azurin specifically targets P-cadherin, not E-cadherin, abrogating P-cadherin-mediated invasive effects and signaling. Therefore, azurin could possibly be considered a therapeutic tool to treat poor-prognosis breast carcinomas overexpressing P-cadherin in a wild type E-cadherin context. 相似文献
992.
Reinhard Gruber Dieter D. Bosshardt Richard J. Miron Anja C. Gemperli Daniel Buser Anton Sculean 《PloS one》2013,8(8)
Enamel matrix derivative (EMD), an extract of fetal porcine enamel, and TGF-β can both suppress adipogenic differentiation. However, there have been no studies that functionally link the role of EMD and TGF-β in vitro. Herein, we examined whether TGF-β signaling contributes to EMD-induced suppression of adipogenic differentiation. Adipogenesis was studied with 3T3-L1 preadipocytes in the presence of SB431542, an inhibitor of TGF-βRI kinase activity. SB431542 reversed the inhibitory effect of EMD on adipogenic differentiation, based on Oil Red O staining and mRNA expression of lipid regulated genes. SB431542 also reduced EMD-stimulated expression of connective tissue growth factor (CTGF), an autocrine inhibitor of adipogenic differentiation. Moreover, short interfering (si)RNAs for CTGF partially reversed the EMD-induced suppression of lipid regulated genes. We conclude that the TGF-βRI - CTGF axis is involved in the anti-adipogenic effects of EMD in vitro. 相似文献
993.
Ines Yang Daniel Eibach Friederike Kops Birgit Brenneke Sabrina Woltemate Jessika Schulze André Bleich Achim D. Gruber Sureshkumar Muthupalani James G. Fox Christine Josenhans Sebastian Suerbaum 《PloS one》2013,8(8)
The mouse pathobiont Helicobacter hepaticus can induce typhlocolitis in interleukin-10-deficient mice, and H. hepaticus infection of immunodeficient mice is widely used as a model to study the role of pathogens and commensal bacteria in the pathogenesis of inflammatory bowel disease. C57BL/6J Il10−/− mice kept under specific pathogen-free conditions in two different facilities (MHH and MIT), displayed strong differences with respect to their susceptibilities to H. hepaticus-induced intestinal pathology. Mice at MIT developed robust typhlocolitis after infection with H. hepaticus, while mice at MHH developed no significant pathology after infection with the same H. hepaticus strain. We hypothesized that the intestinal microbiota might be responsible for these differences and therefore performed high resolution analysis of the intestinal microbiota composition in uninfected mice from the two facilities by deep sequencing of partial 16S rRNA amplicons. The microbiota composition differed markedly between mice from both facilities. Significant differences were also detected between two groups of MHH mice born in different years. Of the 119 operational taxonomic units (OTUs) that occurred in at least half the cecum or colon samples of at least one mouse group, 24 were only found in MIT mice, and another 13 OTUs could only be found in MHH samples. While most of the MHH-specific OTUs could only be identified to class or family level, the MIT-specific set contained OTUs identified to genus or species level, including the opportunistic pathogen, Bilophila wadsworthia. The susceptibility to H. hepaticus-induced colitis differed considerably between Il10−/− mice originating from the two institutions. This was associated with significant differences in microbiota composition, highlighting the importance of characterizing the intestinal microbiome when studying murine models of IBD. 相似文献
994.
995.
A Modified RNA-Seq Approach for Whole Genome Sequencing of RNA Viruses from Faecal and Blood Samples
Elizabeth M. Batty T. H. Nicholas Wong Amy Trebes Karène Argoud Moustafa Attar David Buck Camilla L. C. Ip Tanya Golubchik Madeleine Cule Rory Bowden Charis Manganis Paul Klenerman Eleanor Barnes A. Sarah Walker David H. Wyllie Daniel J. Wilson Kate E. Dingle Tim E. A. Peto Derrick W. Crook Paolo Piazza 《PloS one》2013,8(6)
To date, very large scale sequencing of many clinically important RNA viruses has been complicated by their high population molecular variation, which creates challenges for polymerase chain reaction and sequencing primer design. Many RNA viruses are also difficult or currently not possible to culture, severely limiting the amount and purity of available starting material. Here, we describe a simple, novel, high-throughput approach to Norovirus and Hepatitis C virus whole genome sequence determination based on RNA shotgun sequencing (also known as RNA-Seq). We demonstrate the effectiveness of this method by sequencing three Norovirus samples from faeces and two Hepatitis C virus samples from blood, on an Illumina MiSeq benchtop sequencer. More than 97% of reference genomes were recovered. Compared with Sanger sequencing, our method had no nucleotide differences in 14,019 nucleotides (nt) for Noroviruses (from a total of 2 Norovirus genomes obtained with Sanger sequencing), and 8 variants in 9,542 nt for Hepatitis C virus (1 variant per 1,193 nt). The three Norovirus samples had 2, 3, and 2 distinct positions called as heterozygous, while the two Hepatitis C virus samples had 117 and 131 positions called as heterozygous. To confirm that our sample and library preparation could be scaled to true high-throughput, we prepared and sequenced an additional 77 Norovirus samples in a single batch on an Illumina HiSeq 2000 sequencer, recovering >90% of the reference genome in all but one sample. No discrepancies were observed across 118,757 nt compared between Sanger and our custom RNA-Seq method in 16 samples. By generating viral genomic sequences that are not biased by primer-specific amplification or enrichment, this method offers the prospect of large-scale, affordable studies of RNA viruses which could be adapted to routine diagnostic laboratory workflows in the near future, with the potential to directly characterize within-host viral diversity. 相似文献
996.
Elizabeth Broadbent Vinayak Kumar Xingyan Li John Sollers rd Rebecca Q. Stafford Bruce A. MacDonald Daniel M. Wegner 《PloS one》2013,8(8)
It is important for robot designers to know how to make robots that interact effectively with humans. One key dimension is robot appearance and in particular how humanlike the robot should be. Uncanny Valley theory suggests that robots look uncanny when their appearance approaches, but is not absolutely, human. An underlying mechanism may be that appearance affects users’ perceptions of the robot’s personality and mind. This study aimed to investigate how robot facial appearance affected perceptions of the robot’s mind, personality and eeriness. A repeated measures experiment was conducted. 30 participants (14 females and 16 males, mean age 22.5 years) interacted with a Peoplebot healthcare robot under three conditions in a randomized order: the robot had either a humanlike face, silver face, or no-face on its display screen. Each time, the robot assisted the participant to take his/her blood pressure. Participants rated the robot’s mind, personality, and eeriness in each condition. The robot with the humanlike face display was most preferred, rated as having most mind, being most humanlike, alive, sociable and amiable. The robot with the silver face display was least preferred, rated most eerie, moderate in mind, humanlikeness and amiability. The robot with the no-face display was rated least sociable and amiable. There was no difference in blood pressure readings between the robots with different face displays. Higher ratings of eeriness were related to impressions of the robot with the humanlike face display being less amiable, less sociable and less trustworthy. These results suggest that the more humanlike a healthcare robot’s face display is, the more people attribute mind and positive personality characteristics to it. Eeriness was related to negative impressions of the robot’s personality. Designers should be aware that the face on a robot’s display screen can affect both the perceived mind and personality of the robot. 相似文献
997.
Engineering organs and tissues with the spatial composition and organisation of their native equivalents remains a major challenge. One approach to engineer such spatial complexity is to recapitulate the gradients in regulatory signals that during development and maturation are believed to drive spatial changes in stem cell differentiation. Mesenchymal stem cell (MSC) differentiation is known to be influenced by both soluble factors and mechanical cues present in the local microenvironment. The objective of this study was to engineer a cartilaginous tissue with a native zonal composition by modulating both the oxygen tension and mechanical environment thorough the depth of MSC seeded hydrogels. To this end, constructs were radially confined to half their thickness and subjected to dynamic compression (DC). Confinement reduced oxygen levels in the bottom of the construct and with the application of DC, increased strains across the top of the construct. These spatial changes correlated with increased glycosaminoglycan accumulation in the bottom of constructs, increased collagen accumulation in the top of constructs, and a suppression of hypertrophy and calcification throughout the construct. Matrix accumulation increased for higher hydrogel cell seeding densities; with DC further enhancing both glycosaminoglycan accumulation and construct stiffness. The combination of spatial confinement and DC was also found to increase proteoglycan-4 (lubricin) deposition toward the top surface of these tissues. In conclusion, by modulating the environment through the depth of developing constructs, it is possible to suppress MSC endochondral progression and to engineer tissues with zonal gradients mimicking certain aspects of articular cartilage. 相似文献
998.
Lêda N. Regis Ridelane Veiga Acioli José Constantino Silveira Jr. Maria Alice Varjal Melo-Santos Wayner Vieira Souza Candida M. Nogueira. Ribeiro Juliana C. Serafim. da Silva Antonio Miguel Vieira Monteiro Cláudia M. F. Oliveira Rosangela M. R. Barbosa Cynthia Braga Marco Aurélio Benedetti Rodrigues Marilú Gomes N. M. Silva Paulo Justiniano Ribeiro Jr. Wagner Hugo Bonat Liliam César de Castro Medeiros Marilia Sa Carvalho André Freire Furtado 《PloS one》2013,8(7)
Aedes aegypti has developed evolution-driven adaptations for surviving in the domestic human habitat. Several trap models have been designed considering these strategies and tested for monitoring this efficient vector of Dengue. Here, we report a real-scale evaluation of a system for monitoring and controlling mosquito populations based on egg sampling coupled with geographic information systems technology. The SMCP-Aedes, a system based on open technology and open data standards, was set up from March/2008 to October/2011 as a pilot trial in two sites of Pernambuco -Brazil: Ipojuca (10,000 residents) and Santa Cruz (83,000), in a joint effort of health authorities and staff, and a network of scientists providing scientific support. A widespread infestation by Aedes was found in both sites in 2008–2009, with 96.8%–100% trap positivity. Egg densities were markedly higher in SCC than in Ipojuca. A 90% decrease in egg density was recorded in SCC after two years of sustained control pressure imposed by suppression of >7,500,000 eggs and >3,200 adults, plus larval control by adding fishes to cisterns. In Ipojuca, 1.1 million mosquito eggs were suppressed and a 77% reduction in egg density was achieved. This study aimed at assessing the applicability of a system using GIS and spatial statistic analysis tools for quantitative assessment of mosquito populations. It also provided useful information on the requirements for reducing well-established mosquito populations. Results from two cities led us to conclude that the success in markedly reducing an Aedes population required the appropriate choice of control measures for sustained mass elimination guided by a user-friendly mosquito surveillance system. The system was able to support interventional decisions and to assess the program’s success. Additionally, it created a stimulating environment for health staff and residents, which had a positive impact on their commitment to the dengue control program. 相似文献
999.
Dorsaf Hedhli Olivier Denis Daniel Barkan Mamadou Daffé Michael S. Glickman Kris Huygen 《PloS one》2013,8(10)
The existing vaccine against tuberculosis (M. bovis BCG) exerts some protection against the extrapulmonary forms of the disease, particularly in young children, but is not very effective against the pulmonary form of TB, which often results from the reactivation of a latent M. tuberculosis (M.tb)infection. Among the new approaches in TB vaccine development, live attenuated M.tb mutants are a promising new avenue. Here we report on the vaccine potential of two highly attenuated M.tb mutants, MGM1991 and M.tbhma::hyg (HMA), lacking all oxygenated mycolates in their cell wall. In C57BL/6 mice, stronger Th1 (IFN-γ, IL-2 and TNF-α) and IL-17 responses could be induced following subcutaneous vaccination with either of the two mutants, than following vaccination with M. bovis BCG. Significantly more mycobacteria specific IFN-γ producing CD4+ and particularly CD8+ T cells could be detected by intracellular cytokine staining in mice vaccinated with the M.tb mutants. Finally, vaccination with either of the two mutants conferred stronger protection against intratracheal M.tb challenge than vaccination with BCG, as indicated by reduced bacterial replication in lungs at 4 to 12 weeks after challenge. Protection against M. tb dissemination, as indicated by reduced bacterial numbers in spleen, was comparable for both mutants to protection conferred by BCG. 相似文献
1000.
Daniel H. Lopez Maria A. Fiol-deRoque Maria A. Noguera-Salvà Silvia Terés Federica Campana Stefano Piotto José A. Castro Raheem J. Mohaibes Pablo V. Escribá Xavier Busquets 《PloS one》2013,8(8)