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Sample records for small interfering rna-mediated

  1. Small RNA-Mediated Epigenetic Myostatin Silencing

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    Thomas C Roberts

    2012-01-01

    Full Text Available Myostatin (Mstn is a secreted growth factor that negatively regulates muscle mass and is therefore a potential pharmacological target for the treatment of muscle wasting disorders such as Duchenne muscular dystrophy. Here we describe a novel Mstn blockade approach in which small interfering RNAs (siRNAs complementary to a promoter-associated transcript induce transcriptional gene silencing (TGS in two differentiated mouse muscle cell lines. Silencing is sensitive to treatment with the histone deacetylase inhibitor trichostatin A, and the silent state chromatin mark H3K9me2 is enriched at the Mstn promoter following siRNA transfection, suggesting epigenetic remodeling underlies the silencing effect. These observations suggest that long-term epigenetic silencing may be feasible for Mstn and that TGS is a promising novel therapeutic strategy for the treatment of muscle wasting disorders.

  2. Small RNA-mediated regulation in bacteria: A growing palette of diverse mechanisms.

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    Dutta, Tanmay; Srivastava, Shubhangi

    2018-03-01

    Small RNAs (sRNAs) in bacteria have evolved with diverse mechanisms to balance their target gene expression in response to changes in the environment. Accumulating studies on bacterial regulatory processes firmly established that sRNAs modulate their target gene expression generally at the posttranscriptional level. Identification of large number of sRNAs by advanced technologies, like deep sequencing, tilling microarray, indicates the existence of a plethora of distinctive sRNA-mediated regulatory mechanisms in bacteria. Types of the novel mechanisms are increasing with the discovery of new sRNAs. Complementary base pairing between sRNAs and target RNAs assisted by RNA chaperones like Hfq and ProQ in many occasions, to regulate the cognate gene expression is prevalent in sRNA mechanisms. sRNAs, in most studied cases, can directly base pair with target mRNA to remodel its expression. Base pairing can happen either in the untranslated regions or in the coding regions of mRNA to activate/repress its translation. sRNAs also act as target mimic to titrate away different regulatory RNAs from its target. Other mechanism includes the sequestration of regulatory proteins, especially transcription factors, by sRNAs. Numerous sRNAs, following analogous mechanism, are widespread in bacteria and, thus, has drawn immense attention for the development of RNA-based technologies. Nevertheless, typical sRNA mechanisms are also discovered to be confined in some bacteria. Analysis of the sRNA mechanisms unravels their existence in both the single step processes and the complex regulatory networks with a global effect on cell physiology. This review deals with the diverse array of mechanisms, which sRNAs follow to maintain bacterial lifestyle. Copyright © 2017. Published by Elsevier B.V.

  3. Small RNA-mediated regulation of DNA dosage in the ciliateOxytricha.

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    Khurana, Jaspreet S; Clay, Derek M; Moreira, Sandrine; Wang, Xing; Landweber, Laura F

    2018-01-01

    Dicer-dependent small noncoding RNAs play important roles in gene regulation in a wide variety of organisms. Endogenous small interfering RNAs (siRNAs) are part of an ancient pathway of transposon control in plants and animals. The ciliate, Oxytricha trifallax, has approximately 16,000 gene-sized chromosomes in its somatic nucleus. Long noncoding RNAs establish high ploidy levels at the onset of sexual development, but the factors that regulate chromosome copy numbers during cell division and growth have been a mystery. We report a novel function of a class of Dicer (Dcl-1)- and RNA-dependent RNA polymerase (RdRP)-dependent endogenous small RNAs in regulating chromosome copy number and gene dosage in O. trifallax Asexually growing populations express an abundant class of 21-nt sRNAs that map to both coding and noncoding regions of most chromosomes. These sRNAs are bound to chromatin and their levels surprisingly do not correlate with mRNA levels. Instead, the levels of these small RNAs correlate with genomic DNA copy number. Reduced sRNA levels in dcl-1 or rdrp mutants lead to concomitant reduction in chromosome copy number. Furthermore, these cells show no signs of transposon activation, but instead display irregular nuclear architecture and signs of replication stress. In conclusion, Oxytricha Dcl-1 and RdRP-dependent small RNAs that derive from the somatic nucleus contribute to the maintenance of gene dosage, possibly via a role in DNA replication, offering a novel role for these small RNAs in eukaryotes. © 2018 Khurana et al.; Published by Cold Spring Harbor Laboratory Press for the RNA Society.

  4. Distinct Effects of p19 RNA Silencing Suppressor on Small RNA Mediated Pathways in Plants.

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    Levente Kontra

    2016-10-01

    Full Text Available RNA silencing is one of the main defense mechanisms employed by plants to fight viruses. In change, viruses have evolved silencing suppressor proteins to neutralize antiviral silencing. Since the endogenous and antiviral functions of RNA silencing pathway rely on common components, it was suggested that viral suppressors interfere with endogenous silencing pathway contributing to viral symptom development. In this work, we aimed to understand the effects of the tombusviral p19 suppressor on endogenous and antiviral silencing during genuine virus infection. We showed that ectopically expressed p19 sequesters endogenous small RNAs (sRNAs in the absence, but not in the presence of virus infection. Our presented data question the generalized model in which the sequestration of endogenous sRNAs by the viral suppressor contributes to the viral symptom development. We further showed that p19 preferentially binds the perfectly paired ds-viral small interfering RNAs (vsiRNAs but does not select based on their sequence or the type of the 5' nucleotide. Finally, co-immunoprecipitation of sRNAs with AGO1 or AGO2 from virus-infected plants revealed that p19 specifically impairs vsiRNA loading into AGO1 but not AGO2. Our findings, coupled with the fact that p19-expressing wild type Cymbidium ringspot virus (CymRSV overcomes the Nicotiana benthamiana silencing based defense killing the host, suggest that AGO1 is the main effector of antiviral silencing in this host-virus combination.

  5. Small RNA-mediated Cry toxin silencing allows Bacillus thuringiensis to evade Caenorhabditis elegans avoidance behavioral defenses

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    Peng, Donghai; Luo, Xiaoxia; Zhang, Ni; Guo, Suxia; Zheng, Jinshui; Chen, Ling

    2018-01-01

    Abstract Pathogen avoidance behavior protects animal hosts against microbial pathogens. Pathogens have evolved specific strategies during coevolution in response to such host defenses. However, these strategies for combatting host avoidance behavioral defenses remain poorly understood. Here, we used Caenorhabditis elegans and its bacterial pathogen Bacillus thuringiensis as a model and determined that small RNA (sRNA)-mediated Cry toxin silencing allowed pathogens to evade host avoidance behavioral defenses. The B. thuringiensis strain YBT-1518, which encodes three nematicidal cry genes, is highly toxic to C. elegans. However, the expression of the most potent toxin, Cry5Ba, was silenced in this strain when YBT-1518 was outside the host. Cry5Ba silencing was due to the sRNA BtsR1, which bound to the RBS site of the cry5Ba transcript via direct base pairing and inhibited Cry5Ba expression. Upon ingestion by C. elegans, Cry5Ba was expressed in vivo by strain YBT-1518. Cry5Ba silencing may allow B. thuringiensis to avoid nematode behavioral defenses and then express toxins once ingested to kill the host and gain a survival advantage. Our work describes a novel model of sRNA-mediated regulation to aid pathogens in combating host avoidance behavioral defenses. PMID:29069426

  6. Pulmonary administration of small interfering RNA : The route to go?

    NARCIS (Netherlands)

    Ruigrok, Mitchel; Frijlink, Henderik W.; Hinrichs, Wouter

    2016-01-01

    Ever since the discovery of RNA interference (RNAi), which is a post-transcriptional gene silencing mechanism, researchers have been studying the therapeutic potential of using small interfering RNA (siRNA) to treat diseases that are characterized by excessive gene expression. Excessive gene

  7. Systematic characterization of artificial small RNA-mediated inhibition of Escherichia coli growth.

    Science.gov (United States)

    Noro, Emiko; Mori, Masaru; Makino, Gakuto; Takai, Yuki; Ohnuma, Sumiko; Sato, Asako; Tomita, Masaru; Nakahigashi, Kenji; Kanai, Akio

    2017-02-01

    A new screening system for artificial small RNAs (sRNAs) that inhibit the growth of Escherichia coli was constructed. In this system, we used a plasmid library to express RNAs of ∼120 nucleotides, each with a random 30-nucleotide sequence that can recognize its target mRNA(s). After approximately 60,000 independent colonies were screened, several plasmids that inhibited bacterial growth were isolated. To understand the inhibitory mechanism, we focused on one sRNA, S-20, that exerted a strong inhibitory effect. A time-course analysis of the proteome of S-20-expressing E. coli and a bioinformatic analysis were used to identify potential S-20 target mRNAs, and suggested that S-20 binds the translation initiation sites of several mRNAs encoding enzymes such as peroxiredoxin (osmC), glycyl-tRNA synthetase α subunit (glyQ), uncharacterized protein ygiM, and tryptophan synthase β chain (trpB). An in vitro translation analysis of chimeric luciferase-encoding mRNAs, each containing a potential S-20 target sequence, indicated that the translation of these mRNAs was inhibited in the presence of S-20. A gel shift analysis combined with the analysis of a series of S-20 mutants suggested that S-20 targets multiple mRNAs that are responsible for inhibiting E. coli growth. These data also suggest that S-20 acts like an endogenous sRNA and that E. coli can utilize artificial sRNAs.

  8. Viral small interfering RNAs target host genes to mediate disease symptoms in plants.

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    Neil A Smith

    2011-05-01

    Full Text Available The Cucumber mosaic virus (CMV Y-satellite RNA (Y-Sat has a small non-protein-coding RNA genome that induces yellowing symptoms in infected Nicotiana tabacum (tobacco. How this RNA pathogen induces such symptoms has been a longstanding question. We show that the yellowing symptoms are a result of small interfering RNA (siRNA-directed RNA silencing of the chlorophyll biosynthetic gene, CHLI. The CHLI mRNA contains a 22-nucleotide (nt complementary sequence to the Y-Sat genome, and in Y-Sat-infected plants, CHLI expression is dramatically down-regulated. Small RNA sequencing and 5' RACE analyses confirmed that this 22-nt sequence was targeted for mRNA cleavage by Y-Sat-derived siRNAs. Transformation of tobacco with a RNA interference (RNAi vector targeting CHLI induced Y-Sat-like symptoms. In addition, the symptoms of Y-Sat infection can be completely prevented by transforming tobacco with a silencing-resistant variant of the CHLI gene. These results suggest that siRNA-directed silencing of CHLI is solely responsible for the Y-Sat-induced symptoms. Furthermore, we demonstrate that two Nicotiana species, which do not develop yellowing symptoms upon Y-Sat infection, contain a single nucleotide polymorphism within the siRNA-targeted CHLI sequence. This suggests that the previously observed species specificity of Y-Sat-induced symptoms is due to natural sequence variation in the CHLI gene, preventing CHLI silencing in species with a mismatch to the Y-Sat siRNA. Taken together, these findings provide the first demonstration of small RNA-mediated viral disease symptom production and offer an explanation of the species specificity of the viral disease.

  9. Molecular Basis for the Immunostimulatory Potency of Small Interfering RNAs

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    Mouldy Sioud

    2006-01-01

    Full Text Available Small interfering RNAs (siRNAs represent a new class of antigene agents, which has emerged as a powerful tool for functional genomics and might serve as a potent therapeutic approach. However, several studies have showed that they could trigger several bystander effects, including immune activation and inhibition of unintended target genes. Although activation of innate immunity by siRNAs might be beneficial for therapy in some instances, uncontrolled activation can be toxic, and is therefore a major challenging problem. Interestingly, replacement of uridines in siRNA sequences with their 2′-modified counterparts abrogated siRNA bystander effects. Here we highlight these important findings that are expected to facilitate the rational design of siRNAs that avoid the induction of bystander effects.

  10. Unravelling the complexity of microRNA-mediated gene regulation in black pepper (Piper nigrum L.) using high-throughput small RNA profiling.

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    Asha, Srinivasan; Sreekumar, Sweda; Soniya, E V

    2016-01-01

    Analysis of high-throughput small RNA deep sequencing data, in combination with black pepper transcriptome sequences revealed microRNA-mediated gene regulation in black pepper ( Piper nigrum L.). Black pepper is an important spice crop and its berries are used worldwide as a natural food additive that contributes unique flavour to foods. In the present study to characterize microRNAs from black pepper, we generated a small RNA library from black pepper leaf and sequenced it by Illumina high-throughput sequencing technology. MicroRNAs belonging to a total of 303 conserved miRNA families were identified from the sRNAome data. Subsequent analysis from recently sequenced black pepper transcriptome confirmed precursor sequences of 50 conserved miRNAs and four potential novel miRNA candidates. Stem-loop qRT-PCR experiments demonstrated differential expression of eight conserved miRNAs in black pepper. Computational analysis of targets of the miRNAs showed 223 potential black pepper unigene targets that encode diverse transcription factors and enzymes involved in plant development, disease resistance, metabolic and signalling pathways. RLM-RACE experiments further mapped miRNA-mediated cleavage at five of the mRNA targets. In addition, miRNA isoforms corresponding to 18 miRNA families were also identified from black pepper. This study presents the first large-scale identification of microRNAs from black pepper and provides the foundation for the future studies of miRNA-mediated gene regulation of stress responses and diverse metabolic processes in black pepper.

  11. Design, simplified cloning, and in-silico analysis of multisite small interfering RNA-targeting cassettes

    OpenAIRE

    Baghban-Kohnehrouz, Bahram; Nayeri, Shahnoush

    2016-01-01

    Multiple gene silencing is being required to target and tangle metabolic pathways in eukaryotes and researchers have to develop a subtle method for construction of RNA interference (RNAi) cassettes. Although, several vectors have been developed due to different screening and cloning strategies but still some potential limitations remain to be dissolved. Here, we worked out a simple cloning strategy to develop multisite small interfering RNA (siRNA) cassette from different genes by two cloning...

  12. Protection Against Lethal Marburg Virus Infection Mediated by Lipid Encapsulated Small Interfering RNA

    OpenAIRE

    Ursic-Bedoya, Raul; Mire, Chad E.; Robbins, Marjorie; Geisbert, Joan B.; Judge, Adam; MacLachlan, Ian; Geisbert, Thomas W.

    2013-01-01

    Background.  Marburg virus (MARV) infection causes severe morbidity and mortality in humans and nonhuman primates. Currently, there are no licensed therapeutics available for treating MARV infection. Here, we present the in vitro development and in vivo evaluation of lipid-encapsulated small interfering RNA (siRNA) as a potential therapeutic for the treatment of MARV infection. Methods.  The activity of anti-MARV siRNAs was assessed using dual luciferase reporter assays followed by in vitro t...

  13. Creation of transgenic rice plants producing small interfering RNA of Rice tungro spherical virus.

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    Le, Dung Tien; Chu, Ha Duc; Sasaya, Takahide

    2015-01-01

    Rice tungro spherical virus (RTSV), also known as Rice waika virus, does not cause visible symptoms in infected rice plants. However, the virus plays a critical role in spreading Rice tungro bacilliform virus (RTBV), which is the major cause of severe symptoms of rice tungro disease. Recent studies showed that RNA interference (RNAi) can be used to develop virus-resistance transgenic rice plants. In this report, we presented simple procedures and protocols needed for the creation of transgenic rice plants capable of producing small interfering RNA specific against RTSV sequences. Notably, our study showed that 60 out of 64 individual hygromycin-resistant lines (putative transgenic lines) obtained through transformation carried transgenes designed for producing hairpin double-stranded RNA. Northern blot analyses revealed the presence of small interfering RNA of 21- to 24-mer in 46 out of 56 confirmed transgenic lines. Taken together, our study indicated that transgenic rice plants carrying an inverted repeat of 500-bp fragments encoding various proteins of RTSV can produce small interfering RNA from the hairpin RNA transcribed from that transgene. In light of recent studies with other viruses, it is possible that some of these transgenic rice lines might be resistant to RTSV.

  14. Small interference RNA-mediated knockdown of sperm associated antigen 9 having structural homology with c-Jun N-terminal kinase-interacting protein

    International Nuclear Information System (INIS)

    Rana, Ritu; Jagadish, Nirmala; Garg, Manoj; Mishra, Deepshikha; Dahiya, Neetu; Chaurasiya, Dipak; Suri, Anil

    2006-01-01

    Recently, we reported a novel testis-specific sperm associated antigen 9 (SPAG9) protein, a new member of the JNK-interacting protein family, having a functional role in sperm-egg fusion [N. Jagadish, R. Rana, R. Selvi, D. Mishra, M. Garg, S. Yadav, J.C. Herr, K. Okumura, A. Hasegawa, K. Koyama, A. Suri, Biochem. J. 389 (2005) 73-82]. NCBI Blast searches revealed SPAG9 nucleotide sequence similarities with ESTs of various cancerous tissues. In the present study, we compared the efficiency of two independent SPAG9 specific small interfering RNA (siRNA) constructs, BS/U6/spag9 and BS/U6/spag9-I, to ablate the SPAG9 expression in mammalian cells. A positive correlation between the ratio of target gene versus siRNA and the suppression of SPAG9 expression was observed. Further, the cotransfection of BS/U6/spag9 with pcDNA-SPAG9 and pFlag-CMV2-JNK-3 resulted in specific suppression of SPAG9 without affecting JNK-3 expression. The present investigation will eventually extend the application of SPAG9 siRNA in in vivo targeting experiments that aim to define the SPAG9 functional genomics in tumor and reproductive biology

  15. Incorporation of osteogenic and angiogenic small interfering RNAs into chitosan sponge for bone tissue engineering

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    Jia S

    2014-11-01

    Full Text Available Sen Jia,1,* Xinjie Yang,1,* Wen Song,2,* Lei Wang,1 Kaixiu Fang,3 Zhiqiang Hu,1,4 Zihui Yang,1 Chun Shan,1 Delin Lei,1 Bin Lu1 1Department of Oral and Maxillofacial Surgery, 2Department of Prosthetic Dentistry, 3Department of Implant Dentistry, School of Stomatology, State Key Laboratory of Military Stomatology, Fourth Military Medical University, Xi’an People’s Republic of China; 4Department of Otorhinolaryngology, No 113 Hospital of People’s Liberation Army, Ningbo, People’s Republic of China *These authors contributed to this paper equally and are considered to be joint first authors Abstract: Engineered bone substitutes are being extensively explored in response to growing demand. However, the angiogenesis that occurs during bone formation is often overlooked in scaffold design. In this novel study, we incorporated two small interfering RNAs (siRNAs, ie, small interfering RNA targets casein kinase 2 interaction protein 1 (siCkip-1 and small interfering RNA targets soluble VEGF receptor 1 (siFlt-1, which can promote osteogenesis and angiogenesis, into a chitosan sponge. This scaffold could maintain siRNAs for over 2 weeks in neutral phosphate-buffered saline and degraded rapidly in the presence of lysozyme. The chitosan sponge with siCkip-1 and siFlt-1 in vitro bioactivity was investigated using mesenchymal stem cells. Target genes were significantly suppressed, and osteocalcin, alkaline phosphatase, and vascular endothelial growth factor were significantly upregulated. Alizarin Red staining revealed that mineralization of the extracellular matrix was markedly enhanced by dual transfection. Further analysis by immunofluorescence confirmed that the siRNA-modified scaffold simultaneously improved the expression of osteocalcin and von Willebrand factor. In vivo testing in a skull critical-size defect model showed marked bone regeneration in rats treated with siCkip-1 and siFlt-1. In conclusion, chitosan sponge containing osteogenic and

  16. Phytophthora have distinct endogenous small RNA populations that include short interfering and microRNAs.

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    Noah Fahlgren

    Full Text Available In eukaryotes, RNA silencing pathways utilize 20-30-nucleotide small RNAs to regulate gene expression, specify and maintain chromatin structure, and repress viruses and mobile genetic elements. RNA silencing was likely present in the common ancestor of modern eukaryotes, but most research has focused on plant and animal RNA silencing systems. Phytophthora species belong to a phylogenetically distinct group of economically important plant pathogens that cause billions of dollars in yield losses annually as well as ecologically devastating outbreaks. We analyzed the small RNA-generating components of the genomes of P. infestans, P. sojae and P. ramorum using bioinformatics, genetic, phylogenetic and high-throughput sequencing-based methods. Each species produces two distinct populations of small RNAs that are predominantly 21- or 25-nucleotides long. The 25-nucleotide small RNAs were primarily derived from loci encoding transposable elements and we propose that these small RNAs define a pathway of short-interfering RNAs that silence repetitive genetic elements. The 21-nucleotide small RNAs were primarily derived from inverted repeats, including a novel microRNA family that is conserved among the three species, and several gene families, including Crinkler effectors and type III fibronectins. The Phytophthora microRNA is predicted to target a family of amino acid/auxin permeases, and we propose that 21-nucleotide small RNAs function at the post-transcriptional level. The functional significance of microRNA-guided regulation of amino acid/auxin permeases and the association of 21-nucleotide small RNAs with Crinkler effectors remains unclear, but this work provides a framework for testing the role of small RNAs in Phytophthora biology and pathogenesis in future work.

  17. Phytophthora have distinct endogenous small RNA populations that include short interfering and microRNAs.

    Science.gov (United States)

    Fahlgren, Noah; Bollmann, Stephanie R; Kasschau, Kristin D; Cuperus, Josh T; Press, Caroline M; Sullivan, Christopher M; Chapman, Elisabeth J; Hoyer, J Steen; Gilbert, Kerrigan B; Grünwald, Niklaus J; Carrington, James C

    2013-01-01

    In eukaryotes, RNA silencing pathways utilize 20-30-nucleotide small RNAs to regulate gene expression, specify and maintain chromatin structure, and repress viruses and mobile genetic elements. RNA silencing was likely present in the common ancestor of modern eukaryotes, but most research has focused on plant and animal RNA silencing systems. Phytophthora species belong to a phylogenetically distinct group of economically important plant pathogens that cause billions of dollars in yield losses annually as well as ecologically devastating outbreaks. We analyzed the small RNA-generating components of the genomes of P. infestans, P. sojae and P. ramorum using bioinformatics, genetic, phylogenetic and high-throughput sequencing-based methods. Each species produces two distinct populations of small RNAs that are predominantly 21- or 25-nucleotides long. The 25-nucleotide small RNAs were primarily derived from loci encoding transposable elements and we propose that these small RNAs define a pathway of short-interfering RNAs that silence repetitive genetic elements. The 21-nucleotide small RNAs were primarily derived from inverted repeats, including a novel microRNA family that is conserved among the three species, and several gene families, including Crinkler effectors and type III fibronectins. The Phytophthora microRNA is predicted to target a family of amino acid/auxin permeases, and we propose that 21-nucleotide small RNAs function at the post-transcriptional level. The functional significance of microRNA-guided regulation of amino acid/auxin permeases and the association of 21-nucleotide small RNAs with Crinkler effectors remains unclear, but this work provides a framework for testing the role of small RNAs in Phytophthora biology and pathogenesis in future work.

  18. Phytophthora Have Distinct Endogenous Small RNA Populations That Include Short Interfering and microRNAs

    Science.gov (United States)

    Fahlgren, Noah; Bollmann, Stephanie R.; Kasschau, Kristin D.; Cuperus, Josh T.; Press, Caroline M.; Sullivan, Christopher M.; Chapman, Elisabeth J.; Hoyer, J. Steen; Gilbert, Kerrigan B.; Grünwald, Niklaus J.; Carrington, James C.

    2013-01-01

    In eukaryotes, RNA silencing pathways utilize 20-30-nucleotide small RNAs to regulate gene expression, specify and maintain chromatin structure, and repress viruses and mobile genetic elements. RNA silencing was likely present in the common ancestor of modern eukaryotes, but most research has focused on plant and animal RNA silencing systems. Phytophthora species belong to a phylogenetically distinct group of economically important plant pathogens that cause billions of dollars in yield losses annually as well as ecologically devastating outbreaks. We analyzed the small RNA-generating components of the genomes of P. infestans, P. sojae and P. ramorum using bioinformatics, genetic, phylogenetic and high-throughput sequencing-based methods. Each species produces two distinct populations of small RNAs that are predominantly 21- or 25-nucleotides long. The 25-nucleotide small RNAs were primarily derived from loci encoding transposable elements and we propose that these small RNAs define a pathway of short-interfering RNAs that silence repetitive genetic elements. The 21-nucleotide small RNAs were primarily derived from inverted repeats, including a novel microRNA family that is conserved among the three species, and several gene families, including Crinkler effectors and type III fibronectins. The Phytophthora microRNA is predicted to target a family of amino acid/auxin permeases, and we propose that 21-nucleotide small RNAs function at the post-transcriptional level. The functional significance of microRNA-guided regulation of amino acid/auxin permeases and the association of 21-nucleotide small RNAs with Crinkler effectors remains unclear, but this work provides a framework for testing the role of small RNAs in Phytophthora biology and pathogenesis in future work. PMID:24204767

  19. Small interfering ribonucleic acid induces liquid-to-ripple phase transformation in a phospholipid membrane

    Energy Technology Data Exchange (ETDEWEB)

    Choubey, Amit; Nomura, Ken-ichi; Kalia, Rajiv K.; Nakano, Aiichiro; Vashishta, Priya [Collaboratory for Advanced Computing and Simulations, Department of Physics and Astronomy, Department of Computer Science, Department of Chemical Engineering and Materials Science, University of Southern California, Los Angeles, California 90089-0242 (United States)

    2014-09-15

    Small interfering ribonucleic acid (siRNA) molecules play a pivotal role in silencing gene expression via the RNA interference mechanism. A key limitation to the widespread implementation of siRNA therapeutics is the difficulty of delivering siRNA-based drugs to cells. Here, we examine changes in the structure and dynamics of a dipalmitoylphosphatidylcholine bilayer in the presence of a siRNA molecule and mechanical barriers to siRNA transfection in the bilayer. Our all-atom molecular dynamics simulation shows that siRNA induces a liquid crystalline-to-ripple phase transformation in the bilayer. The ripple phase consists of a major region of non-interdigitated and a minor region of interdigitated lipid molecules with an intervening kink. In the ripple phase, hydrocarbon chains of lipid molecules have large compressive stresses, which present a considerable barrier to siRNA transfection.

  20. Trans-acting small interfering RNA4: key to nutraceutical synthesis in 1 grape development?

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    Rock, Christopher D.

    2013-01-01

    The facility and versatility of microRNAs (miRNAs) to evolve and change likely underlies how they have become dominant constituents of eukaryotic genomes. In this opinion article I propose that trans-acting small interfering RNA gene 4 (TAS4) evolution may be important for biosynthesis of polyphenolics, arbuscular symbiosis, and bacterial pathogen etiologies. Expression-based and phylogenetic evidence shows that TAS4 targets two novel grape (Vitis vinifera L.) MYB transcription factors (VvMYBA6, VvMYBA7) that spawn phased siRNAs and likely function in nutraceutical bioflavonoid biosynthesis and fruit development. Characterization of the molecular mechanisms of TAS4 control of plant development and integration into biotic and abiotic stress- and nutrient signaling regulatory networks has applicability to molecular breeding and development of strategies for engineering healthier foods. PMID:23993483

  1. RNA interference against animal viruses: how morbilliviruses generate extended diversity to escape small interfering RNA control.

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    Holz, Carine L; Albina, Emmanuel; Minet, Cécile; Lancelot, Renaud; Kwiatek, Olivier; Libeau, Geneviève; Servan de Almeida, Renata

    2012-01-01

    Viruses are serious threats to human and animal health. Vaccines can prevent viral diseases, but few antiviral treatments are available to control evolving infections. Among new antiviral therapies, RNA interference (RNAi) has been the focus of intensive research. However, along with the development of efficient RNAi-based therapeutics comes the risk of emergence of resistant viruses. In this study, we challenged the in vitro propensity of a morbillivirus (peste des petits ruminants virus), a stable RNA virus, to escape the inhibition conferred by single or multiple small interfering RNAs (siRNAs) against conserved regions of the N gene. Except with the combination of three different siRNAs, the virus systematically escaped RNAi after 3 to 20 consecutive passages. The genetic modifications involved consisted of single or multiple point nucleotide mutations and a deletion of a stretch of six nucleotides, illustrating that this virus has an unusual genomic malleability.

  2. Design, simplified cloning, andin-silicoanalysis of multisite small interfering RNA-targeting cassettes.

    Science.gov (United States)

    Baghban-Kohnehrouz, Bahram; Nayeri, Shahnoush

    2016-03-01

    Multiple gene silencing is being required to target and tangle metabolic pathways in eukaryotes and researchers have to develop a subtle method for construction of RNA interference (RNAi) cassettes. Although, several vectors have been developed due to different screening and cloning strategies but still some potential limitations remain to be dissolved. Here, we worked out a simple cloning strategy to develop multisite small interfering RNA (siRNA) cassette from different genes by two cloning steps. In this method, effective siRNA sites in the target messenger RNAs (mRNAs) were determined using in silico analysis and consecutively arranged to reduce length of inverted repeats. Here, we used one-step (polymerase chain reaction) PCR by designed long primer sets covering the selected siRNA sites. Rapid screening, cost-effective and shorten procedure are advantages of this method compare to PCR classic cloning. Validity of constructs was confirmed by optimal centroid secondary structures with high stability in plants.

  3. Inhibition of Reporter Genes by Small Interfering RNAs in Cell Culture and Living Fish

    DEFF Research Database (Denmark)

    Larashati, Sekar; Schyth, Brian Dall; Lorenzen, Niels

    ). But evidence of specific siRNA inhibition in living fish is still needed. Using the small interfering RNAs (siRNAs), messenger RNA (mRNA) can be targeted resulting in degradation of targeted transcript or translational repression. Reporter genes such as luciferase and green fluorescence protein (GFP) can......RNA interference is a mechanism for silencing specific genes. It has been applied in cell culture to inhibit expression of genes involved in disease including viral genes as recently shown for the fish pathogenic rhabdovirus viral haemorrhagic septicaemia virus or VHSV (Bohle et al., 2011...... embryonic kidney HEK293t cells was used because they are easy to transfect and generally show high expression of transfected genes. Various types of fish including albino trouts and transparent fish were used as animal models to get better visualization of reporter gene expression. High variability...

  4. Analysis of small interfering RNA by capillary electrophoresis in hydroxyethylcellulose solutions.

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    Liu, Chenchen; Yamaguchi, Yoshinori; Zhu, Xifang; Li, Zhenqing; Ni, Yi; Dou, Xiaoming

    2015-07-01

    The analysis of small interfering RNA (siRNA) is important for gene function studies and drug developments. We employed CE to study the separation of siRNA ladder marker, which were ten double-stranded RNA (dsRNA) fragments ranged from 20 to 1000 bp, in solutions of hydroxyethylcellulose (HEC) polymer with different concentrations and molecular weights (Mws). Migration mechanism of dsRNA during CE was studied by the mobility and resolution length (RL) plots. We found that the RL depended on not only the concentration of HEC, but also the Mw of HEC. For instance, RL of small dsRNA fragment was more influenced by concentration of high Mw HEC than large dsRNA fragment and RL of large dsRNA fragment was more influenced by concentration of low Mw HEC than small dsRNA fragment. In addition, we found electrophoretic evidence that the structure of dsRNA was more compact than dsDNA with the same length. In practice, we succeeded to separate the glyceraldehyde 3-phosphate dehydrogenase siRNA in the mixture of the siRNA ladder marker within 4 min. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Nanoparticle-based delivery of small interfering RNA: challenges for cancer therapy

    Directory of Open Access Journals (Sweden)

    Miele E

    2012-07-01

    Full Text Available Evelina Miele,1,* Gian Paolo Spinelli,2,* Ermanno Miele,3 Enzo Di Fabrizio,3,6 Elisabetta Ferretti,4 Silverio Tomao,2 Alberto Gulino,1,5 1Department of Molecular Medicine, 2Department of Medico-Surgical Sciences and Biotechnologies, Sapienza University of Rome, Rome, 3Nanostructures, Istituto Italiano di Tecnologia, via Morego, 30, 16163 Genova, 4Department of Experimental Medicine, Sapienza University of Rome, Rome, 5Center for Life Nanoscience, Istituto Italiano di Tecnologia, Rome, Italy, 6BIONEM lab, University of Magna Graecia, Campus S. Venuta, Viale Europa 88100 Catanzaro, Italy *These authors contributed equally to this workAbstract: During recent decades there have been remarkable advances and profound changes in cancer therapy. Many therapeutic strategies learned at the bench, including monoclonal antibodies and small molecule inhibitors, have been used at the bedside, leading to important successes. One of the most important advances in biology has been the discovery that small interfering RNA (siRNA is able to regulate the expression of genes, by a phenomenon known as RNA interference (RNAi. RNAi is one of the most rapidly growing fields of research in biology and therapeutics. Much research effort has gone into the application of this new discovery in the treatment of various diseases, including cancer. However, even though these molecules may have potential and strong utility, some limitations make their clinical application difficult, including delivery problems, side effects due to off-target actions, disturbance of physiological functions of the cellular machinery involved in gene silencing, and induction of the innate immune response. Many researchers have attempted to overcome these limitations and to improve the safety of potential RNAi-based therapeutics. Nanoparticles, which are nanostructured entities with tunable size, shape, and surface, as well as biological behavior, provide an ideal opportunity to modify current

  6. A novel albumin nanocomplex containing both small interfering RNA and gold nanorods for synergetic anticancer therapy

    Science.gov (United States)

    Choi, Jin-Ha; Hwang, Hai-Jin; Shin, Seung Won; Choi, Jeong-Woo; Um, Soong Ho; Oh, Byung-Keun

    2015-05-01

    Therapeutic nanocomplexes have been extensively developed for the effective treatment of aggressive cancers because of their outstanding versatility, easy manipulation, and low cytotoxicity. In this study, we describe the synthesis of a novel bovine serum albumin (BSA)-based nanocomplex harboring both Bcl-2-specific small interfering RNA (siRNA) and gold (Au) nanorods (siRNA and rods encapsulated in BSA; SREB) with the aim of developing a targeted breast cancer therapeutic. The SREB complexes contained 2 × 105 siRNA molecules and eight Au nanorods per BSA complex and were successively functionalized with polyethylene glycol (PEG) and anti-ErbB-2 antibodies to facilitate active targeting. The synergetic therapeutic activity originating from the two components effectively induced cell death (~80% reduction in viability compared with control cells) in target breast cancer cells after a single dose of laser irradiation. Intracellular SREB nanocomplex decomposition by proteolytic enzymes resulted in simultaneous RNA interference and thermal ablation, thus leading to apoptosis in the targeted cancer cells. Moreover, these therapeutic effects were sustained for approximately 72 hours. The intrinsic biocompatibility, multifunctionality, and potent in vitro anticancer properties of these SREB nanocomplexes indicate that they have great therapeutic potential for in vivo targeted cancer therapy, in addition to other areas of nanomedicine.Therapeutic nanocomplexes have been extensively developed for the effective treatment of aggressive cancers because of their outstanding versatility, easy manipulation, and low cytotoxicity. In this study, we describe the synthesis of a novel bovine serum albumin (BSA)-based nanocomplex harboring both Bcl-2-specific small interfering RNA (siRNA) and gold (Au) nanorods (siRNA and rods encapsulated in BSA; SREB) with the aim of developing a targeted breast cancer therapeutic. The SREB complexes contained 2 × 105 siRNA molecules and eight Au

  7. Efficient and specific gene knockdown by small interfering RNAs produced in bacteria

    Science.gov (United States)

    Huang, Linfeng; Jin, Jingmin; Deighan, Padraig; Kiner, Evgeny; McReynolds, Larry; Lieberman, Judy

    2013-01-01

    Synthetic small interfering RNAs (siRNAs) are an indispensable tool to investigate gene function in eukaryotic cells1,2 and may be used for therapeutic purposes to knockdown genes implicated in disease3. Thus far, most synthetic siRNAs have been produced by chemical synthesis. Here we present a method to produce highly potent siRNAs in E. coli. This method relies on ectopic expression of p19, a siRNA-binding protein found in a plant RNA virus4, 5. When expressed in E. coli, p19 stabilizes ~21 nt siRNA-like species produced by bacterial RNase III. Transfection of mammalian cells with siRNAs, generated in bacteria expressing p19 and a hairpin RNA encoding 200 or more nucleotides of a target gene, at low nanomolar concentrations reproducibly knocks down gene expression by ~90% without immunogenicity or off-target effects. Because bacterially produced siRNAs contain multiple sequences against a target gene, they may be especially useful for suppressing polymorphic cellular or viral genes. PMID:23475073

  8. Efficient inhibition of the formation of joint adhesions by ERK2 small interfering RNAs

    International Nuclear Information System (INIS)

    Li, Fengfeng; Ruan, Hongjiang; Fan, Cunyi; Zeng, Bingfang; Wang, Chunyang; Wang, Xiang

    2010-01-01

    Transforming growth factor-β1 and fibroblast growth factor-2 play very important roles in fibroblast proliferation and collagen expression. These processes lead to the formation of joint adhesions through the SMAD and MAPK pathways, in which extracellular signal-regulated kinase (ERK)2 is considered to be crucial. Based on these theories, we examined the effects of a lentivirus-mediated small interfering RNA (siRNA) targeting ERK2 on the suppression of joint adhesion formation in vivo. The effects were assessed in vivo from different aspects including the adhesion score, histology and joint contracture angle. We found that the adhesions in the ERK2 siRNA group became soft and weak, and were easily stretched. Accordingly, the flexion contracture angles in the ERK2 siRNA group were also reduced (P < 0.05 compared with the control group). The animals appeared healthy, with no signs of impaired wound healing. In conclusion, local delivery of a lentivirus-mediated siRNA targeting ERK2 can ameliorate joint adhesion formation effectively and safely.

  9. Small Interfering RNA Efficiently Suppresses Adhesion Molecule Expression on Pulmonary Microvascular Endothelium

    Directory of Open Access Journals (Sweden)

    Tobias Walker

    2011-01-01

    Full Text Available Background. Adhesion molecules are known to influence postoperative organ function, they are hardly involved in the inflammatory response following the ischemia-reperfusion injury. We sought to investigate the potency of small interfering RNAs to suppress adhesion molecule expression in human pulmonary microvascular endothelial cells. Methods. Human lung microvascular endothelial cells were transfected with specific siRNA followed by a stimulation of the cells with an inflammatory cytokine. Adhesion molecule expression was determined by FACS-analysis, and reduction of intracellular mRNA was determined by qRT-PCR. Furthermore, the attachment of isolated neutrophils on the endothelial layer was determined after siRNA transfection. Results. In summary, siRNA transfection significantly decreased the percentage positive cells in a single cocktail transfection of each adhesion molecule investigated. Adhering neutrophils were diminished as well. Conclusion. siRNA might be a promising tool for the effective suppression of adhesion molecule expression on pulmonary microvascular cells, potentially minimizing leukocyte-endothelial depending interactions of a pulmonary allograft.

  10. Protection Against Lethal Marburg Virus Infection Mediated by Lipid Encapsulated Small Interfering RNA

    Science.gov (United States)

    Ursic-Bedoya, Raul; Mire, Chad E.; Robbins, Marjorie; Geisbert, Joan B.; Judge, Adam; MacLachlan, Ian; Geisbert, Thomas W.

    2014-01-01

    Background. Marburg virus (MARV) infection causes severe morbidity and mortality in humans and nonhuman primates. Currently, there are no licensed therapeutics available for treating MARV infection. Here, we present the in vitro development and in vivo evaluation of lipid-encapsulated small interfering RNA (siRNA) as a potential therapeutic for the treatment of MARV infection. Methods. The activity of anti-MARV siRNAs was assessed using dual luciferase reporter assays followed by in vitro testing against live virus. Lead candidates were tested in lethal guinea pig models of 3 different MARV strains (Angola, Ci67, Ravn). Results. Treatment resulted in 60%–100% survival of guinea pigs infected with MARV. Although treatment with siRNA targeting other MARV messenger RNA (mRNA) had a beneficial effect, targeting the MARV NP mRNA resulted in the highest survival rates. NP-718m siRNA in lipid nanoparticles provided 100% protection against MARV strains Angola and Ci67, and 60% against Ravn. A cocktail containing NP-718m and NP-143m provided 100% protection against MARV Ravn. Conclusions. These data show protective efficacy against the most pathogenic Angola strain of MARV. Further development of the lipid nanoparticle technology has the potential to yield effective treatments for MARV infection. PMID:23990568

  11. Alpha-synuclein suppression by targeted small interfering RNA in the primate substantia nigra.

    Directory of Open Access Journals (Sweden)

    Alison L McCormack

    Full Text Available The protein alpha-synuclein is involved in the pathogenesis of Parkinson's disease and other neurodegenerative disorders. Its toxic potential appears to be enhanced by increased protein expression, providing a compelling rationale for therapeutic strategies aimed at reducing neuronal alpha-synuclein burden. Here, feasibility and safety of alpha-synuclein suppression were evaluated by treating monkeys with small interfering RNA (siRNA directed against alpha-synuclein. The siRNA molecule was chemically modified to prevent degradation by exo- and endonucleases and directly infused into the left substantia nigra. Results compared levels of alpha-synuclein mRNA and protein in the infused (left vs. untreated (right hemisphere and revealed a significant 40-50% suppression of alpha-synuclein expression. These findings could not be attributable to non-specific effects of siRNA infusion since treatment of a separate set of animals with luciferase-targeting siRNA produced no changes in alpha-synuclein. Infusion with alpha-synuclein siRNA, while lowering alpha-synuclein expression, had no overt adverse consequences. In particular, it did not cause tissue inflammation and did not change (i the number and phenotype of nigral dopaminergic neurons, and (ii the concentrations of striatal dopamine and its metabolites. The data represent the first evidence of successful anti-alpha-synuclein intervention in the primate substantia nigra and support further development of RNA interference-based therapeutics.

  12. Genome-wide identification of genes regulated in trans by transposable element small interfering RNAs

    Science.gov (United States)

    McCue, Andrea D; Nuthikattu, Saivageethi; Slotkin, R Keith

    2013-01-01

    Transposable elements (TEs) are known to influence the regulation of neighboring genes through a variety of mechanisms. Additionally, it was recently discovered that TEs can regulate non-neighboring genes through the trans-acting nature of small interfering RNAs (siRNAs). When the epigenetic repression of TEs is lost, TEs become transcriptionally active, and the host cell acts to repress mutagenic transposition by degrading TE mRNAs into siRNAs. In this study, we have performed a genome-wide analysis in the model plant Arabidopsis thaliana and found that TE siRNA-based regulation of genic mRNAs is more pervasive than the two formerly characterized proof-of-principle examples. We identified 27 candidate genic mRNAs that do not contain a TE fragment but are regulated through partial complementarity by the accumulation of TE siRNAs and are therefore influenced by TE epigenetic activation. We have experimentally confirmed several gene targets and demonstrated that they respond to the accumulation of specific 21 nucleotide TE siRNAs that are incorporated into the Arabidopsis Argonaute1 protein. Additionally, we found that one TE siRNA specifically targets and inhibits the formation of a host protein that acts to repress TE activity, suggesting that TEs harbor and potentially evolutionarily select short sequences to act as suppressors of host TE repression. PMID:23863322

  13. Deletion of Cytoplasmic Double-Stranded RNA Sensors Does Not Uncover Viral Small Interfering RNA Production in Human Cells

    NARCIS (Netherlands)

    Schuster, Susan; Tholen, Lotte E; Overheul, Gijs J; van Kuppeveld, Frank J M|info:eu-repo/dai/nl/156614723; van Rij, Ronald P

    2017-01-01

    Antiviral immunity in insects and plants is mediated by the RNA interference (RNAi) pathway in which viral long double-stranded RNA (dsRNA) is processed into small interfering RNAs (siRNAs) by Dicer enzymes. Although this pathway is evolutionarily conserved, its involvement in antiviral defense in

  14. The influenza A virus NS1 protein binds small interfering RNAs and suppresses RNA silencing in plants

    NARCIS (Netherlands)

    Bucher, E.C.; Hemmes, J.C.; Haan, de P.; Goldbach, R.W.; Prins, M.W.

    2004-01-01

    RNA silencing comprises a set of sequence-specific RNA degradation pathways that occur in a wide range of eukaryotes, including animals, fungi and plants. A hallmark of RNA silencing is the presence of small interfering RNA molecules (siRNAs). The siRNAs are generated by cleavage of larger

  15. Global Analyses of Small Interfering RNAs from Sour Orange seedlings Infected with Different Citrus tristeza virus Genotypes

    Science.gov (United States)

    RNA silencing is a sequence-specific regulatory mechanism in development and maintenance of genome integrity and functions in plant antiviral defense mechanisms. Small interfering RNAs (siRNAs) are key mediators of RNA silencing. To study CTV-host interactions and disease expression, profiles of v...

  16. Reconstituted influenza virus envelopes as an efficient carrier system for cellular delivery of small-interfering RNAs

    NARCIS (Netherlands)

    de Jonge, J; Holtrop, M; Wilschut, J; Huckriede, A

    Application of RNA interference for in vivo evaluation of gene function or for therapeutic interventions has been hampered by a lack of suitable delivery methods for small interfering RNA ( siRNA). Here, we present reconstituted viral envelopes (virosomes) derived from influenza virus as suitable

  17. In Silico Reconstruction of Viral Genomes from Small RNAs Improves Virus-Derived Small Interfering RNA Profiling ▿ † ‡

    Science.gov (United States)

    Vodovar, Nicolas; Goic, Bertsy; Blanc, Hervé; Saleh, Maria-Carla

    2011-01-01

    RNA interference (RNAi) is the essential component of antiviral immunity in invertebrates and plants. One of the landmarks of the antiviral RNAi response is the production of virus-derived small interfering RNA (vsiRNA) from viral double-stranded RNA (dsRNA). vsiRNAs constitute a fragmented image of the viral genome sequence that results from Dicer cleavage. vsiRNA sequence profiling is used extensively as a surrogate to study the antiviral RNAi response by determining the nature of the viral dsRNA molecules exposed to and processed by the RNAi machinery. The accuracy of these profiles depends on the actual viral genome sequence used as a reference to align vsiRNA reads, and the interpretation of inaccurate profiles can be misleading. Using Flock house virus and Drosophila melanogaster as a model RNAi-competent organism, we show accurate reconstruction of full-length virus reference sequence from vsiRNAs and prediction of the structure of defective interfering particles (DIs). We developed a Perl script, named Paparazzi, that reconstitutes viral genomes through an iterative alignment/consensus call procedure using a related reference sequence as scaffold. As prevalent DI-derived reads introduce artifacts during reconstruction, Paparazzi eliminates DI-specific reads to improve the quality of the reconstructed genome. Paparazzi constitutes a promising alternative to Sanger sequencing in this context and an effective tool to study antiviral RNAi mechanisms by accurately quantifying vsiRNA along the replicating viral genome. We further discuss Paparazzi as a companion tool for virus discovery as it provides full-length genome sequences and corrects for potential artifacts of assembly. PMID:21880776

  18. Effect of small interfering RNAs on in vitro replication and gene expression of feline coronavirus.

    Science.gov (United States)

    Anis, Eman A; Wilkes, Rebecca P; Kania, Stephen A; Legendre, Alfred M; Kennedy, Melissa A

    2014-09-01

    To evaluate the ability of small interfering RNAs (siRNAs) to inhibit in vitro viral replication and gene expression of feline coronavirus (FCoV). Cell cultures of Crandell-Rees feline kidney cells. 5 synthetic siRNAs that each targeted a different region of the FCoV genome were tested individually and in various combinations for their antiviral effects against 2 strains of FCoV (feline infectious peritonitis virus WSU 79-1146 and feline enteric coronavirus WSU 79-1683) in cell cultures. Tested combinations targeted the FCoV leader and 3' untranslated region, FCoV leader region and nucleocapsid gene, and FCoV leader region, 3' untranslated region, and nucleocapsid gene. For each test condition, assessments included relative quantification of the inhibition of intracellular viral genomic RNA synthesis by means of real-time, reverse-transcription PCR analysis; flow cytometric evaluation of the reduction of viral protein expression in infected cells; and assessment of virus replication inhibition via titration of extracellular virus with a TCID₅₀ infectivity assay. The 5 siRNAs had variable inhibitory effects on FCoV when used singly. Combinations of siRNAs that targeted different regions of the viral genome resulted in more effective viral inhibition than did individual siRNAs that targeted a single gene. The tested siRNA combinations resulted in approximately 95% reduction in viral replication (based on virus titration results), compared with findings in negative control, nontargeting siRNA-treated, FCoV-infected cells. In vitro replication of FCoV was specifically inhibited by siRNAs that targeted coding and noncoding regions of the viral genome, suggesting a potential therapeutic application of RNA interference in treatment of feline infectious peritonitis.

  19. A Convenient In Vivo Model Using Small Interfering RNA Silencing to Rapidly Assess Skeletal Gene Function.

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    Wen Zhang

    Full Text Available It is difficult to study bone in vitro because it contains various cell types that engage in cross-talk. Bone biologically links various organs, and it has thus become increasingly evident that skeletal physiology must be studied in an integrative manner in an intact animal. We developed a model using local intraosseous small interfering RNA (siRNA injection to rapidly assess the effects of a target gene on the local skeletal environment. In this model, 160-g male Sprague-Dawley rats were treated for 1-2 weeks. The left tibia received intraosseous injection of a parathyroid hormone 1 receptor (Pth1r or insulin-like growth factor 1 receptor (Igf-1r siRNA transfection complex loaded in poloxamer 407 hydrogel, and the right tibia received the same volume of control siRNA. All the tibias received an intraosseous injection of recombinant human parathyroid hormone (1-34 (rhPTH (1-34 or insulin-like growth factor-1 (IGF-1. Calcein green and alizarin red were injected 6 and 2 days before euthanasia, respectively. IGF-1R and PTH1R expression levels were detected via RT-PCR assays and immunohistochemistry. Bone mineral density (BMD, microstructure, mineral apposition rates (MARs, and strength were determined by dual-energy X-ray absorptiometry, micro-CT, histology and biomechanical tests. The RT-PCR and immunohistochemistry results revealed that IGF-1R and PTH1R expression levels were dramatically diminished in the siRNA-treated left tibias compared to the right tibias (both p<0.05. Using poloxamer 407 hydrogel as a controlled-release system prolonged the silencing effect of a single dose of siRNA; the mRNA expression levels of IGF-1R were lower at two weeks than at one week (p<0.01. The BMD, bone microstructure parameters, MAR and bone strength were significantly decreased in the left tibias compared to the right tibias (all p<0.05. This simple and convenient local intraosseous siRNA injection model achieved gene silencing with very small quantities of

  20. Functional specialization of the small interfering RNA pathway in response to virus infection.

    Directory of Open Access Journals (Sweden)

    Joao Trindade Marques

    Full Text Available In Drosophila, post-transcriptional gene silencing occurs when exogenous or endogenous double stranded RNA (dsRNA is processed into small interfering RNAs (siRNAs by Dicer-2 (Dcr-2 in association with a dsRNA-binding protein (dsRBP cofactor called Loquacious (Loqs-PD. siRNAs are then loaded onto Argonaute-2 (Ago2 by the action of Dcr-2 with another dsRBP cofactor called R2D2. Loaded Ago2 executes the destruction of target RNAs that have sequence complementarity to siRNAs. Although Dcr-2, R2D2, and Ago2 are essential for innate antiviral defense, the mechanism of virus-derived siRNA (vsiRNA biogenesis and viral target inhibition remains unclear. Here, we characterize the response mechanism mediated by siRNAs against two different RNA viruses that infect Drosophila. In both cases, we show that vsiRNAs are generated by Dcr-2 processing of dsRNA formed during viral genome replication and, to a lesser extent, viral transcription. These vsiRNAs seem to preferentially target viral polyadenylated RNA to inhibit viral replication. Loqs-PD is completely dispensable for silencing of the viruses, in contrast to its role in silencing endogenous targets. Biogenesis of vsiRNAs is independent of both Loqs-PD and R2D2. R2D2, however, is required for sorting and loading of vsiRNAs onto Ago2 and inhibition of viral RNA expression. Direct injection of viral RNA into Drosophila results in replication that is also independent of Loqs-PD. This suggests that triggering of the antiviral pathway is not related to viral mode of entry but recognition of intrinsic features of virus RNA. Our results indicate the existence of a vsiRNA pathway that is separate from the endogenous siRNA pathway and is specifically triggered by virus RNA. We speculate that this unique framework might be necessary for a prompt and efficient antiviral response.

  1. Rapid delivery of small interfering RNA by biosurfactant MEL-A-containing liposomes

    International Nuclear Information System (INIS)

    Inoh, Yoshikazu; Furuno, Tadahide; Hirashima, Naohide; Kitamoto, Dai; Nakanishi, Mamoru

    2011-01-01

    Highlights: ► We use MEL-A-containing cationic liposomes for siRNA delivery. ► MEL-A-containing cationic liposomes can efficiently and rapidly deliver siRNA into the cytoplasm. ► Rapid delivery of siRNA is due to the membrane fusion between liposomes and plasma membrane. -- Abstract: The downregulation of gene expression by RNA interference holds great potential for genetic analysis and gene therapy. However, a more efficient delivery system for small interfering RNA (siRNA) into the target cells is required for wide fields such as cell biology, physiology, and clinical application. Non-viral vectors are stronger candidates than viral vectors because they are safer and easier to prepare. We have previously used a new method for gene transfection by combining cationic liposomes with the biosurfactant mannosylerythritol lipid-A (MEL-A). The novel MEL-A-containing cationic liposomes rapidly delivered DNA (plasmids and oligonucleotides) into the cytosol and nucleus through membrane fusion between liposomes and the plasma membrane, and consequently, enhanced the gene transfection efficiency. In this study, we determined the efficiency of MEL-A-containing cationic liposomes for siRNA delivery. We observed that exogenous and endogenous protein expression was suppressed by approximately 60% at 24 h after brief (30 min) incubation of target cells with MEL-A-containing cationic liposome/siRNA complexes. Confocal microscopic analysis showed that suppression of protein expression was caused by rapid siRNA delivery into the cytosol. We found that the MEL-A-containing cationic liposomes directly delivered siRNA into the cytoplasm by the membrane fusion in addition to endocytotic pathway whereas Lipofectamine™ RNAiMax delivered siRNA only by the endocytotic pathway. It seems that the ability to rapidly and directly deliver siRNA into the cytosol using MEL-A-containing cationic liposomes is able to reduce immune responses, cytotoxicity, and other side effects caused by

  2. Rapid delivery of small interfering RNA by biosurfactant MEL-A-containing liposomes

    Energy Technology Data Exchange (ETDEWEB)

    Inoh, Yoshikazu; Furuno, Tadahide [School of Pharmacy, Aichi Gakuin University, 1-100 Kusumoto-cho, Chikusa-ku, Nagoya 464-8650 (Japan); Hirashima, Naohide [Graduate School of Pharmaceutical Sciences, Nagoya City University, 3-1 Tanabe-dori, Mizuho-ku, Nagoya 467-8603 (Japan); Kitamoto, Dai [National Institute of Advanced Industrial Science and Technology (AIST), Central 5, 1-1 Higashi, Tsukuba 305-8565 (Japan); Nakanishi, Mamoru, E-mail: mamoru@dpc.agu.ac.jp [School of Pharmacy, Aichi Gakuin University, 1-100 Kusumoto-cho, Chikusa-ku, Nagoya 464-8650 (Japan)

    2011-10-28

    Highlights: Black-Right-Pointing-Pointer We use MEL-A-containing cationic liposomes for siRNA delivery. Black-Right-Pointing-Pointer MEL-A-containing cationic liposomes can efficiently and rapidly deliver siRNA into the cytoplasm. Black-Right-Pointing-Pointer Rapid delivery of siRNA is due to the membrane fusion between liposomes and plasma membrane. -- Abstract: The downregulation of gene expression by RNA interference holds great potential for genetic analysis and gene therapy. However, a more efficient delivery system for small interfering RNA (siRNA) into the target cells is required for wide fields such as cell biology, physiology, and clinical application. Non-viral vectors are stronger candidates than viral vectors because they are safer and easier to prepare. We have previously used a new method for gene transfection by combining cationic liposomes with the biosurfactant mannosylerythritol lipid-A (MEL-A). The novel MEL-A-containing cationic liposomes rapidly delivered DNA (plasmids and oligonucleotides) into the cytosol and nucleus through membrane fusion between liposomes and the plasma membrane, and consequently, enhanced the gene transfection efficiency. In this study, we determined the efficiency of MEL-A-containing cationic liposomes for siRNA delivery. We observed that exogenous and endogenous protein expression was suppressed by approximately 60% at 24 h after brief (30 min) incubation of target cells with MEL-A-containing cationic liposome/siRNA complexes. Confocal microscopic analysis showed that suppression of protein expression was caused by rapid siRNA delivery into the cytosol. We found that the MEL-A-containing cationic liposomes directly delivered siRNA into the cytoplasm by the membrane fusion in addition to endocytotic pathway whereas Lipofectamine Trade-Mark-Sign RNAiMax delivered siRNA only by the endocytotic pathway. It seems that the ability to rapidly and directly deliver siRNA into the cytosol using MEL-A-containing cationic

  3. Delivery of small interfering RNAs in human cervical cancer cells by polyethylenimine-functionalized carbon nanotubes

    Science.gov (United States)

    Huang, Yuan-Pin; Lin, I.-Jou; Chen, Chih-Chen; Hsu, Yi-Chiang; Chang, Chi-Chang; Lee, Mon-Juan

    2013-06-01

    Carbon nanotubes are capable of penetrating the cell membrane and are widely considered as potential carriers for gene or drug delivery. Because the C-C and C=C bonds in carbon nanotubes are nonpolar, functionalization is required for carbon nanotubes to interact with genes or drugs as well as to improve their biocompatibility. In this study, polyethylenimine (PEI)-functionalized single-wall (PEI-NH-SWNTs) and multiwall carbon nanotubes (PEI-NH-MWNTs) were produced by direct amination method. PEI functionalization increased the positive charge on the surface of SWNTs and MWNTs, allowing carbon nanotubes to interact electrostatically with the negatively charged small interfering RNAs (siRNAs) and to serve as nonviral gene delivery reagents. PEI-NH-MWNTs and PEI-NH-SWNTs had a better solubility in water than pristine carbon nanotubes, and further removal of large aggregates by centrifugation produced a stable suspension of reduced particle size and improved homogeneity and dispersity. The amount of grafted PEI estimated by thermogravimetric analysis was 5.08% ( w/ w) and 5.28% ( w/ w) for PEI-NH-SWNTs and PEI-NH-MWNTs, respectively. For the assessment of cytotoxicity, various concentrations of PEI-NH-SWNTs and PEI-NH-MWNTs were incubated with human cervical cancer cells, HeLa-S3, for 48 h. PEI-NH-SWNTs and PEI-NH-MWNTs induced cell deaths in a dose-dependent manner but were less cytotoxic compared to pure PEI. As determined by electrophoretic mobility shift assay, siRNAs directed against glyceraldehyde-3-phosphate dehydrogenase (siGAPDH) were completely associated with PEI-NH-SWNTs or PEI-NH-MWNTs at a PEI-NH-SWNT/siGAPDH or PEI-NH-MWNT/siGAPDH mass ratio of 80:1 or 160:1, respectively. Furthermore, PEI-NH-SWNTs and PEI-NH-MWNTs successfully delivered siGAPDH into HeLa-S3 cells at PEI-NH-SWNT/siGAPDH and PEI-NH-MWNT/siGAPDH mass ratios of 1:1 to 20:1, resulting in suppression of the mRNA level of GAPDH to an extent similar to that of DharmaFECT, a common transfection

  4. Small RNA and Transcriptome Sequencing Reveal a Potential miRNA-Mediated Interaction Network That Functions during Somatic Embryogenesis in Lilium pumilum DC. Fisch.

    Science.gov (United States)

    Zhang, Jing; Xue, Bingyang; Gai, Meizhu; Song, Shengli; Jia, Nana; Sun, Hongmei

    2017-01-01

    Plant somatic embryos are widely used in the fields of germplasm conservation, breeding for genetic engineering and artificial seed production. MicroRNAs (miRNAs) play pivotal roles in somatic embryogenesis (SE) regulation. However, their regulatory roles during various stages of SE remain unclear. In this study, six types of embryogenic samples of Lilium pumilum DC. Fisch., including organogenic callus, embryogenic callus induced for 4 weeks, embryogenic callus induced for 6 weeks, globular embryos, torpedo embryos and cotyledon embryos, were prepared for small RNA sequencing. The results revealed a total of 2,378,760 small RNA reads, among which the most common size was 24 nt. Four hundred and fifty-two known miRNAs, belonging to more than 86 families, 57 novel miRNAs and 40 miRNA*s were identified. The 86 known miRNA families were sorted according to an alignment with their homologs across 24 land plants into the following four categories: 23 highly conserved, 4 moderately conserved, 15 less conserved and 44 species-specific miRNAs. Differentially expressed known miRNAs were identified during various stages of SE. Subsequently, the expression levels of 12 differentially expressed miRNAs and 4 targets were validated using qRT-PCR. In addition, six samples were mixed in equal amounts for transcript sequencing, and the sequencing data were used as transcripts for miRNA target prediction. A total of 66,422 unigenes with an average length of 800 bp were assembled from 56,258,974 raw reads. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment indicated that 38,004 and 15,497 unigenes were successfully assigned to GO terms and KEGG pathways, respectively. Among the unigenes, 2,182 transcripts were predicted to be targets for 396 known miRNAs. The potential targets of the identified miRNAs were mostly classified into the following GO terms: cell, binding and metabolic process. Enriched KEGG analysis demonstrated that carbohydrate metabolism

  5. A small interfering RNA screen of genes involved in DNA repair identifies tumor-specific radiosensitization by POLQ knockdown

    DEFF Research Database (Denmark)

    Higgins, Geoff S; Prevo, Remko; Lee, Yin-Fai

    2010-01-01

    ) and irradiated normal tissue cells (MRC5). Using gammaH2AX foci at 24 hours after IR, we identified several genes, such as BRCA2, Lig IV, and XRCC5, whose knockdown is known to cause increased cell radiosensitivity, thereby validating the primary screening end point. In addition, we identified POLQ (DNA...... radiosensitivity are largely unknown. We have conducted a small interfering RNA (siRNA) screen of 200 genes involved in DNA damage repair aimed at identifying genes whose knockdown increased tumor radiosensitivity. Parallel siRNA screens were conducted in irradiated and unirradiated tumor cells (SQ20B...

  6. Control of African swine fever virus replication by small interfering RNA targeting the A151R and VP72 genes.

    Science.gov (United States)

    Keita, Djénéba; Heath, Livio; Albina, Emmanuel

    2010-01-01

    African swine fever virus (ASFV) is the unique member of the Asfarviridae family and Asfivirus genus. It is an enveloped double-stranded DNA arbovirus that replicates in the cell cytoplasm, similar to poxviruses. There is no vaccine and no treatment available to control this virus. We describe the use of small interfering RNA (siRNA) targeting the A151R and VP72 (B646L) genes to control the ASFV replication in vitro. Results suggest that siRNA targeting the A151R and VP72 genes can reduce both the virus replication and its levels of messenger RNA transcripts. The reduction was up to 4 log(10) copies on the virus titre and up to 3 log(10) copies on virus RNA transcripts levels. The combination of multiple siRNA did not improve the antiviral effect significantly, compared with use of individual siRNAs. The function of the A151R gene product in the virus replication cycle is yet unclear, but is essential. We also demonstrate that it is possible to inhibit, using small interfering RNA, a virus that replicates exclusively in the cell cytoplasm in specific viral factories.

  7. The exosome and trans-acting small interfering RNAs regulate cuticular wax biosynthesis during Arabidopsis inflorescence stem development.

    Science.gov (United States)

    Lam, Patricia; Zhao, Lifang; Eveleigh, Nathan; Yu, Yu; Chen, Xuemei; Kunst, Ljerka

    2015-02-01

    The primary aerial surfaces of land plants are covered with a cuticle, a protective layer composed of the cutin polyester matrix and cuticular waxes. Previously, we discovered a unique mechanism of regulating cuticular wax biosynthesis during Arabidopsis (Arabidopsis thaliana) stem elongation that involves ECERIFERUM7 (CER7), a core subunit of the exosome. Because loss-of-function mutations in CER7 result in reduced expression of the wax biosynthetic gene CER3, we proposed that CER7 is involved in degrading a messenger RNA encoding a CER3 repressor. To identify this putative repressor, we performed a cer7 suppressor screen that resulted in the isolation of the posttranscriptional gene-silencing components RNA-DEPENDENT RNA POLYMERASE1 and SUPPRESSOR OF GENE SILENCING3, indicating that small RNAs regulate CER3 expression. To establish the identity of the effector RNA species and determine whether these RNAs control CER3 transcript levels directly, we cloned additional genes identified in our suppressor screen and performed next-generation sequencing of small RNA populations that differentially accumulate in the cer7 mutant in comparison with the wild type. Our results demonstrate that the trans-acting small interfering RNA class of small RNAs are the effector molecules involved in direct silencing of CER3 and that the expression of five additional genes (EARLY RESPONSE TO DEHYDRATION14, AUXIN RESISTANT1, a translation initiation factor SUI1 family protein, and two genes of unknown function) is controlled by both CER7 and trans-acting small interfering RNAs. © 2015 American Society of Plant Biologists. All Rights Reserved.

  8. Global analyses of small interfering RNAs derived from Bamboo mosaic virus and its associated satellite RNAs in different plants.

    Science.gov (United States)

    Lin, Kuan-Yu; Cheng, Chi-Ping; Chang, Bill Chia-Han; Wang, Wei-Chi; Huang, Ying-Wen; Lee, Yun-Shien; Huang, Hsien-Da; Hsu, Yau-Heiu; Lin, Na-Sheng

    2010-08-02

    Satellite RNAs (satRNAs), virus parasites, are exclusively associated with plant virus infection and have attracted much interest over the last 3 decades. Upon virus infection, virus-specific small interfering RNAs (vsiRNAs) are produced by dicer-like (DCL) endoribonucleases for anti-viral defense. The composition of vsiRNAs has been studied extensively; however, studies of satRNA-derived siRNAs (satsiRNAs) or siRNA profiles after satRNA co-infection are limited. Here, we report on the small RNA profiles associated with infection with Bamboo mosaic virus (BaMV) and its two satellite RNAs (satBaMVs) in Nicotiana benthamiana and Arabidopsis thaliana. Leaves of N. benthamiana or A. thaliana inoculated with water, BaMV alone or co-inoculated with interfering or noninterfering satBaMV were collected for RNA extraction, then large-scale Solexa sequencing. Up to about 20% of total siRNAs as BaMV-specific siRNAs were accumulated in highly susceptible N. benthamiana leaves inoculated with BaMV alone or co-inoculated with noninterfering satBaMV; however, only about 0.1% of vsiRNAs were produced in plants co-infected with interfering satBaMV. The abundant region of siRNA distribution along BaMV and satBaMV genomes differed by host but not by co-infection with satBaMV. Most of the BaMV and satBaMV siRNAs were 21 or 22 nt, of both (+) and (-) polarities; however, a higher proportion of 22-nt BaMV and satBaMV siRNAs were generated in N. benthamiana than in A. thaliana. Furthermore, the proportion of non-viral 24-nt siRNAs was greatly increased in N. benthamiana after virus infection. The overall composition of vsiRNAs and satsiRNAs in the infected plants reflect the combined action of virus, satRNA and different DCLs in host plants. Our findings suggest that the structure and/or sequence demands of various DCLs in different hosts may result in differential susceptibility to the same virus. DCL2 producing 24-nt siRNAs under biotic stresses may play a vital role in the antiviral

  9. Interfering with DNA Damage Signals: Radiosensitizing Prostate Cancer Using Small Peptides

    Science.gov (United States)

    2009-05-01

    Higuera, B. Xu, P. R. Andreassen, R. C. Gregory, S. T. Kim, W. S. Lane, M. B. Kastan, and A. D. D’Andrea. 2002. Convergence of the fanconi anemia and... de - fects, chromosomal instability, and hypersensitivity in re- sponse to IR. ATM is remarkable for its large size and the existence of a sequence in...of transporting small peptides and proteins across the plasma membrane (Fuchs and Raines, 2004; De - shayes et al., 2005) Three peptides were generated

  10. CRISPR transcript processing: a mechanism for generating a large number of small interfering RNAs

    OpenAIRE

    Djordjevic Marko; Djordjevic Magdalena; Severinov Konstantin

    2012-01-01

    Abstract Background CRISPR/Cas (Clustered Regularly Interspaced Short Palindromic Repeats/CRISPR associated sequences) is a recently discovered prokaryotic defense system against foreign DNA, including viruses and plasmids. CRISPR cassette is transcribed as a continuous transcript (pre-crRNA), which is processed by Cas proteins into small RNA molecules (crRNAs) that are responsible for defense against invading viruses. Experiments in E. coli report that overexpression of cas genes generates a...

  11. Profile of small interfering RNAs from cotton plants infected with the polerovirus Cotton leafroll dwarf virus

    Directory of Open Access Journals (Sweden)

    Schrago Carlos EG

    2011-08-01

    Full Text Available Abstract Background In response to infection, viral genomes are processed by Dicer-like (DCL ribonuclease proteins into viral small RNAs (vsRNAs of discrete sizes. vsRNAs are then used as guides for silencing the viral genome. The profile of vsRNAs produced during the infection process has been extensively studied for some groups of viruses. However, nothing is known about the vsRNAs produced during infections of members of the economically important family Luteoviridae, a group of phloem-restricted viruses. Here, we report the characterization of a population of vsRNAs from cotton plants infected with Cotton leafroll dwarf virus (CLRDV, a member of the genus Polerovirus, family Luteoviridae. Results Deep sequencing of small RNAs (sRNAs from leaves of CLRDV-infected cotton plants revealed that the vsRNAs were 21- to 24-nucleotides (nt long and that their sequences matched the viral genome, with higher frequencies of matches in the 3- region. There were equivalent amounts of sense and antisense vsRNAs, and the 22-nt class of small RNAs was predominant. During infection, cotton Dcl transcripts appeared to be up-regulated, while Dcl2 appeared to be down-regulated. Conclusions This is the first report on the profile of sRNAs in a plant infected with a virus from the family Luteoviridae. Our sequence data strongly suggest that virus-derived double-stranded RNA functions as one of the main precursors of vsRNAs. Judging by the profiled size classes, all cotton DCLs might be working to silence the virus. The possible causes for the unexpectedly high accumulation of 22-nt vsRNAs are discussed. CLRDV is the causal agent of Cotton blue disease, which occurs worldwide. Our results are an important contribution for understanding the molecular mechanisms involved in this and related diseases.

  12. CRISPR transcript processing: a mechanism for generating a large number of small interfering RNAs

    Directory of Open Access Journals (Sweden)

    Djordjevic Marko

    2012-07-01

    Full Text Available Abstract Background CRISPR/Cas (Clustered Regularly Interspaced Short Palindromic Repeats/CRISPR associated sequences is a recently discovered prokaryotic defense system against foreign DNA, including viruses and plasmids. CRISPR cassette is transcribed as a continuous transcript (pre-crRNA, which is processed by Cas proteins into small RNA molecules (crRNAs that are responsible for defense against invading viruses. Experiments in E. coli report that overexpression of cas genes generates a large number of crRNAs, from only few pre-crRNAs. Results We here develop a minimal model of CRISPR processing, which we parameterize based on available experimental data. From the model, we show that the system can generate a large amount of crRNAs, based on only a small decrease in the amount of pre-crRNAs. The relationship between the decrease of pre-crRNAs and the increase of crRNAs corresponds to strong linear amplification. Interestingly, this strong amplification crucially depends on fast non-specific degradation of pre-crRNA by an unidentified nuclease. We show that overexpression of cas genes above a certain level does not result in further increase of crRNA, but that this saturation can be relieved if the rate of CRISPR transcription is increased. We furthermore show that a small increase of CRISPR transcription rate can substantially decrease the extent of cas gene activation necessary to achieve a desired amount of crRNA. Conclusions The simple mathematical model developed here is able to explain existing experimental observations on CRISPR transcript processing in Escherichia coli. The model shows that a competition between specific pre-crRNA processing and non-specific degradation determines the steady-state levels of crRNA and is responsible for strong linear amplification of crRNAs when cas genes are overexpressed. The model further shows how disappearance of only a few pre-crRNA molecules normally present in the cell can lead to a large (two

  13. CRISPR transcript processing: a mechanism for generating a large number of small interfering RNAs

    Science.gov (United States)

    2012-01-01

    Background CRISPR/Cas (Clustered Regularly Interspaced Short Palindromic Repeats/CRISPR associated sequences) is a recently discovered prokaryotic defense system against foreign DNA, including viruses and plasmids. CRISPR cassette is transcribed as a continuous transcript (pre-crRNA), which is processed by Cas proteins into small RNA molecules (crRNAs) that are responsible for defense against invading viruses. Experiments in E. coli report that overexpression of cas genes generates a large number of crRNAs, from only few pre-crRNAs. Results We here develop a minimal model of CRISPR processing, which we parameterize based on available experimental data. From the model, we show that the system can generate a large amount of crRNAs, based on only a small decrease in the amount of pre-crRNAs. The relationship between the decrease of pre-crRNAs and the increase of crRNAs corresponds to strong linear amplification. Interestingly, this strong amplification crucially depends on fast non-specific degradation of pre-crRNA by an unidentified nuclease. We show that overexpression of cas genes above a certain level does not result in further increase of crRNA, but that this saturation can be relieved if the rate of CRISPR transcription is increased. We furthermore show that a small increase of CRISPR transcription rate can substantially decrease the extent of cas gene activation necessary to achieve a desired amount of crRNA. Conclusions The simple mathematical model developed here is able to explain existing experimental observations on CRISPR transcript processing in Escherichia coli. The model shows that a competition between specific pre-crRNA processing and non-specific degradation determines the steady-state levels of crRNA and is responsible for strong linear amplification of crRNAs when cas genes are overexpressed. The model further shows how disappearance of only a few pre-crRNA molecules normally present in the cell can lead to a large (two orders of magnitude

  14. Characterization of small interfering RNAs derived from Rice black streaked dwarf virus in infected maize plants by deep sequencing.

    Science.gov (United States)

    Li, Mingjun; Li, Yongqiang; Xia, Zihao; Di, Dianping; Zhang, Aihong; Miao, Hongqin; Zhou, Tao; Fan, Zaifeng

    2017-01-15

    Rice black streaked dwarf virus (RBSDV) is the casual agent of maize rough dwarf disease, which frequently causes severe yield loss in China. However, the interaction between RBSDV and maize plants is largely unknown. RNA silencing is a conserved mechanism against viruses in plants. To understand the antiviral RNA interfering response in RBSDV-infected plants, the profile of virus-derived small interfering RNAs (vsiRNAs) from RBSDV in infected maize plants was obtained by deep sequencing in this study. Our data showed that vsiRNAs, accumulated preferentially as 21- and 22-nucleotide (nt) species, were mapped against all 10 genomic RNA segments of RBSDV and derived almost equally overall from both positive and negative strands, while there were significant differences in the accumulation level of vsiRNAs from segments 2, 4, 6, 7 and 10. The vsiRNAs (21 and 22 nt) generated from each segment of RBSDV genome had a 5'-terminal nucleotide bias toward adenine and uracil. The single-nucleotide resolution maps showed that RBSDV-derived siRNAs preferentially distributed in the 5'- or 3'-terminal regions of several genomic segments. In addition, our results showed that the mRNA levels of some components involved in antiviral RNA silencing pathway were differentially modified during RBSDV infection. Among them, the accumulation levels of ZmDCL1, ZmDCL2, ZmDCL3a, ZmAGO1a, ZmAGO1b, ZmAGO2a, ZmAGO18a and ZmRDR6 mRNAs were significantly up-regulated, while those of ZmDCL3b, ZmDCL4 and ZmAGO1c mRNAs showed no obvious changes in RBSDV-infected maize plants. Copyright © 2016 Elsevier B.V. All rights reserved.

  15. ABMA, a small molecule that inhibits intracellular toxins and pathogens by interfering with late endosomal compartments.

    Science.gov (United States)

    Wu, Yu; Pons, Valérie; Goudet, Amélie; Panigai, Laetitia; Fischer, Annette; Herweg, Jo-Ana; Kali, Sabrina; Davey, Robert A; Laporte, Jérôme; Bouclier, Céline; Yousfi, Rahima; Aubenque, Céline; Merer, Goulven; Gobbo, Emilie; Lopez, Roman; Gillet, Cynthia; Cojean, Sandrine; Popoff, Michel R; Clayette, Pascal; Le Grand, Roger; Boulogne, Claire; Tordo, Noël; Lemichez, Emmanuel; Loiseau, Philippe M; Rudel, Thomas; Sauvaire, Didier; Cintrat, Jean-Christophe; Gillet, Daniel; Barbier, Julien

    2017-11-14

    Intracellular pathogenic microorganisms and toxins exploit host cell mechanisms to enter, exert their deleterious effects as well as hijack host nutrition for their development. A potential approach to treat multiple pathogen infections and that should not induce drug resistance is the use of small molecules that target host components. We identified the compound 1-adamantyl (5-bromo-2-methoxybenzyl) amine (ABMA) from a cell-based high throughput screening for its capacity to protect human cells and mice against ricin toxin without toxicity. This compound efficiently protects cells against various toxins and pathogens including viruses, intracellular bacteria and parasite. ABMA provokes Rab7-positive late endosomal compartment accumulation in mammalian cells without affecting other organelles (early endosomes, lysosomes, the Golgi apparatus, the endoplasmic reticulum or the nucleus). As the mechanism of action of ABMA is restricted to host-endosomal compartments, it reduces cell infection by pathogens that depend on this pathway to invade cells. ABMA may represent a novel class of broad-spectrum compounds with therapeutic potential against diverse severe infectious diseases.

  16. Distinct mechanisms determine transposon inheritance and methylation via small interfering RNA and histone modification.

    Directory of Open Access Journals (Sweden)

    Zachary Lippman

    2003-12-01

    Full Text Available Heritable, but reversible, changes in transposable element activity were first observed in maize by Barbara McClintock in the 1950s. More recently, transposon silencing has been associated with DNA methylation, histone H3 lysine-9 methylation (H3mK9, and RNA interference (RNAi. Using a genetic approach, we have investigated the role of these modifications in the epigenetic regulation and inheritance of six Arabidopsis transposons. Silencing of most of the transposons is relieved in DNA methyltransferase (met1, chromatin remodeling ATPase (ddm1, and histone modification (sil1 mutants. In contrast, only a small subset of the transposons require the H3mK9 methyltransferase KRYPTONITE, the RNAi gene ARGONAUTE1, and the CXG methyltransferase CHROMOMETHYLASE3. In crosses to wild-type plants, epigenetic inheritance of active transposons varied from mutant to mutant, indicating these genes differ in their ability to silence transposons. According to their pattern of transposon regulation, the mutants can be divided into two groups, which suggests that there are distinct, but interacting, complexes or pathways involved in transposon silencing. Furthermore, different transposons tend to be susceptible to different forms of epigenetic regulation.

  17. The "Trojan horse" model-delivery of anti-HBV small interfering RNAs by a recombinant HBV vector.

    Science.gov (United States)

    Shlomai, Amir; Lubelsky, Yoav; Har-Noy, Ofir; Shaul, Yosef

    2009-12-18

    Hepatitis B virus (HBV) is a small virus that infects the liver. The major obstacle in applying the RNA interference method as an anti-HBV weapon is the challenge to deliver the small interfering RNA molecules to the liver efficiently and specifically. Here we show that HBV-specific short hairpin RNAs (shRNAs) are efficiently expressed from a recombinant HBV into which an shRNA-expressing cassette was inserted, resulting in a significant knock-down of HBV gene expression. Notably, this recombinant HBV still expresses the HBV Core protein, which is targeted by the shRNAs produced by the same vector. Our results set the stage for further use of this recombinant HBV virus with the potential to function as a "Trojan horse"; one that specifically targets the liver and uses the resident virus as an helper for its own propagation, and at the same time eliminate itself and the resident HBV by knocking-down their gene expression.

  18. Comparison of small interfering RNA (siRNA) delivery into bovine monocyte-derived macrophages by transfection and electroporation.

    Science.gov (United States)

    Jensen, Kirsty; Anderson, Jennifer A; Glass, Elizabeth J

    2014-04-15

    The manipulation of the RNA interference pathway using small interfering RNA (siRNA) has become the most frequently used gene silencing method. However, siRNA delivery into primary cells, especially primary macrophages, is often considered challenging. Here we report the investigation of the suitability of two methodologies: transient transfection and electroporation, to deliver siRNA targeted against the putative immunomodulatory gene Mediterranean fever (MEFV) into primary bovine monocyte-derived macrophages (bMDM). Eleven commercial transfection reagents were investigated with variable results with respect to siRNA uptake, target gene knock-down, cell toxicity and type I interferon (IFN) response induction. Three transfection reagents: Lipofectamine 2000, Lipofectamine RNAiMAX and DharmaFECT 3, were found to consistently give the best results. However, all the transfection reagents tested induced an IFN response in the absence of siRNA, which could be minimized by reducing the transfection reagent incubation period. In addition, optimized siRNA delivery into bMDM by electroporation achieved comparable levels of target gene knock-down as transient transfection, without a detectable IFN response, but with higher levels of cell toxicity. The optimized transient transfection and electroporation methodologies may provide a starting point for optimizing siRNA delivery into macrophages derived from other species or other cells considered difficult to investigate with siRNA. Copyright © 2014 The Authors. Published by Elsevier B.V. All rights reserved.

  19. The use of small interfering RNAs to inhibit adipocyte differentiation in human preadipocytes and fetal-femur-derived mesenchymal cells

    International Nuclear Information System (INIS)

    Xu, Y.; Mirmalek-Sani, S.-H.; Yang, X.; Zhang, J.; Oreffo, R.O.C.

    2006-01-01

    RNA interference (RNAi) has been used in functional genomics and offers innovative approaches in the development of novel therapeutics. Human mesenchymal stem cells offer a unique cell source for tissue engineering/regeneration strategies. The current study examined the potential of small interfering RNAs (siRNA) against human peroxisome proliferator activated receptor gamma (PPARγ) to suppress adipocyte differentiation (adipogenesis) in human preadipocytes and fetal-femur-derived mesenchymal cells. Adipogenesis was investigated using cellular and biochemical analysis. Transient transfection with PPARγ-siRNA using a liposomal-based strategy resulted in a significant inhibition of adipogenesis in human preadipocytes and fetal-femur-derived mesenchymal cells, compared to controls (cell, liposomal and negative siRNA). The inhibitory effect of PPARγ-siRNA was supported by testing human PPARγ mRNA and adipogenic associated genes using reverse transcription polymerase chain reaction (RT-PCR) to adiponectin receptor 1 and 2 as well as examination of fatty acid binding protein 3 (FABP 3 ) expression, an adipocyte-specific marker. The current studies indicate that PPARγ-siRNA is a useful tool to study adipogenesis in human cells, with potential applications both therapeutic and in the elucidation of mesenchymal cell differentiation in the modulation of cell differentiation in human mesenchymal cells

  20. Antiviral activity of Small interfering RNAs: Specificity testing using heterologous virus reveals interferon-related effects overlooked by conventional mismatch controls

    DEFF Research Database (Denmark)

    Schyth, Brian Dall; Lorenzen, Niels; Pedersen, Finn Skou

    2006-01-01

    RNA interference by small interfering RNAs (siRNAs) is considered to be a highly specific method for knockdown of gene expression in eukaryotic cells via degradation of target mRNA. Mutated siRNA molecules with 1–4 mismatching nucleotides compared to the target mRNA are regularly used as specific...

  1. Safety assessment of food and feed from biotechnology-derived crops employing RNA-mediated gene regulation to achieve desired traits: a scientific review.

    Science.gov (United States)

    Petrick, Jay S; Brower-Toland, Brent; Jackson, Aimee L; Kier, Larry D

    2013-07-01

    Gene expression can be modulated in plants to produce desired traits through agricultural biotechnology. Currently, biotechnology-derived crops are compared to their conventional counterparts, with safety assessments conducted on the genetic modification and the intended and unintended differences. This review proposes that this comparative safety assessment paradigm is appropriate for plants modified to express mediators of RNA-mediated gene regulation, including RNA interference (RNAi), a gene suppression mechanism that naturally occurs in plants and animals. The molecular mediators of RNAi, including long double-stranded RNAs (dsRNA), small interfering RNAs (siRNA), and microRNAs (miRNA), occur naturally in foods; therefore, there is an extensive history of safe consumption. Systemic exposure following consumption of plants containing dsRNAs that mediate RNAi is limited in higher organisms by extensive degradation of ingested nucleic acids and by biological barriers to uptake and efficacy of exogenous nucleic acids. A number of mammalian RNAi studies support the concept that a large margin of safety will exist for any small fraction of RNAs that might be absorbed following consumption of foods from biotechnology-derived plants that employ RNA-mediated gene regulation. Food and feed derived from these crops utilizing RNA-based mechanisms is therefore expected to be as safe as food and feed derived through conventional plant breeding. Copyright © 2013 Elsevier Inc. All rights reserved.

  2. In vitro evaluation of endothelial exosomes as carriers for small interfering ribonucleic acid delivery

    Directory of Open Access Journals (Sweden)

    Banizs AB

    2014-09-01

    Full Text Available Anna B Banizs,1 Tao Huang,1 Kelly Dryden,2 Stuart S Berr,1 James R Stone,1 Robert K Nakamoto,2 Weibin Shi,1 Jiang He1 1Department of Radiology and Medical Imaging, 2Department of Molecular Physiology and Biological Physics, University of Virginia, Charlottesville, VA, USA Abstract: Exosomes, one subpopulation of nanosize extracellular vesicles derived from multivesicular bodies, ranging from 30 to 150 nm in size, emerged as promising carriers for small interfering ribonucleic acid (siRNA delivery, as they are capable of transmitting molecular messages between cells through carried small noncoding RNAs, messenger RNAs, deoxyribonucleic acids, and proteins. Endothelial cells are involved in a number of important biological processes, and are a major source of circulating exosomes. In this study, we prepared exosomes from endothelial cells and evaluated their capacity to deliver siRNA into primary endothelial cells. Exosomes were isolated and purified by sequential centrifugation and ultracentrifugation from cultured mouse aortic endothelial cells. Similar to exosome particles from other cell sources, endothelial exosomes are nanometer-size vesicles, examined by both the NanoSight instrument and transmission electron microscopy. Enzyme-linked immunosorbent assay analysis confirmed the expression of two exosome markers: CD9 and CD63. Flow cytometry and fluorescence microscopy studies demonstrated that endothelial exosomes were heterogeneously distributed within cells. In a gene-silencing study with luciferase-expressing endothelial cells, exosomes loaded with siRNA inhibited luciferase expression by more than 40%. In contrast, siRNA alone and control siRNA only suppressed luciferase expression by less than 15%. In conclusion, we demonstrated that endothelial exosomes have the capability to accommodate and deliver short foreign nucleic acids into endothelial cells. Keywords: extracellular vesicles, exosomes, gene delivery, siRNA, endothelium

  3. Characterization of small interfering RNAs derived from Sugarcane mosaic virus in infected maize plants by deep sequencing.

    Science.gov (United States)

    Xia, Zihao; Peng, Jun; Li, Yongqiang; Chen, Ling; Li, Shuai; Zhou, Tao; Fan, Zaifeng

    2014-01-01

    RNA silencing is a conserved surveillance mechanism against viruses in plants. It is mediated by Dicer-like (DCL) proteins producing small interfering RNAs (siRNAs), which guide specific Argonaute (AGO)-containing complexes to inactivate viral genomes and may promote the silencing of host mRNAs. In this study, we obtained the profile of virus-derived siRNAs (vsiRNAs) from Sugarcane mosaic virus (SCMV) in infected maize (Zea mays L.) plants by deep sequencing. Our data showed that vsiRNAs which derived almost equally from sense and antisense SCMV RNA strands accumulated preferentially as 21- and 22-nucleotide (nt) species and had an adenosine bias at the 5'-terminus. The single-nucleotide resolution maps revealed that vsiRNAs were almost continuously but heterogeneously distributed throughout the SCMV genome and the hotspots of sense and antisense strands were mainly distributed in the HC-Pro coding region. Moreover, dozens of host transcripts targeted by vsiRNAs were predicted, several of which encode putative proteins involved in ribosome biogenesis and in biotic and abiotic stresses. We also found that ZmDCL2 mRNAs were up-regulated in SCMV-infected maize plants, which may be the cause of abundant 22-nt vsiRNAs production. However, ZmDCL4 mRNAs were down-regulated slightly regardless of the most abundant 21-nt vsiRNAs. Our results also showed that SCMV infection induced the accumulation of AGO2 mRNAs, which may indicate a role for AGO2 in antiviral defense. To our knowledge, this is the first report on vsiRNAs in maize plants.

  4. Characterization of small interfering RNAs derived from Sugarcane mosaic virus in infected maize plants by deep sequencing.

    Directory of Open Access Journals (Sweden)

    Zihao Xia

    Full Text Available RNA silencing is a conserved surveillance mechanism against viruses in plants. It is mediated by Dicer-like (DCL proteins producing small interfering RNAs (siRNAs, which guide specific Argonaute (AGO-containing complexes to inactivate viral genomes and may promote the silencing of host mRNAs. In this study, we obtained the profile of virus-derived siRNAs (vsiRNAs from Sugarcane mosaic virus (SCMV in infected maize (Zea mays L. plants by deep sequencing. Our data showed that vsiRNAs which derived almost equally from sense and antisense SCMV RNA strands accumulated preferentially as 21- and 22-nucleotide (nt species and had an adenosine bias at the 5'-terminus. The single-nucleotide resolution maps revealed that vsiRNAs were almost continuously but heterogeneously distributed throughout the SCMV genome and the hotspots of sense and antisense strands were mainly distributed in the HC-Pro coding region. Moreover, dozens of host transcripts targeted by vsiRNAs were predicted, several of which encode putative proteins involved in ribosome biogenesis and in biotic and abiotic stresses. We also found that ZmDCL2 mRNAs were up-regulated in SCMV-infected maize plants, which may be the cause of abundant 22-nt vsiRNAs production. However, ZmDCL4 mRNAs were down-regulated slightly regardless of the most abundant 21-nt vsiRNAs. Our results also showed that SCMV infection induced the accumulation of AGO2 mRNAs, which may indicate a role for AGO2 in antiviral defense. To our knowledge, this is the first report on vsiRNAs in maize plants.

  5. Silencing of SARS-CoV spike gene by small interfering RNA in HEK 293T cells

    International Nuclear Information System (INIS)

    Qin Zhaoling; Zhao Ping; Zhang Xiaolian; Yu Jianguo; Cao Mingmei; Zhao Lanjuan; Luan Jie; Qi Zhongtian

    2004-01-01

    Two candidate small interfering RNAs (siRNAs) corresponding to severe acute respiratory syndrome-associated coronavirus (SARS-CoV) spike gene were designed and in vitro transcribed to explore the possibility of silencing SARS-CoV S gene. The plasmid pEGFP-optS, which contains the codon-optimized SARS-CoV S gene and expresses spike-EGFP fusion protein (S-EGFP) as silencing target and expressing reporter, was transfected with siRNAs into HEK 293T cells. At various time points of posttransfection, the levels of S-EGFP expression and amounts of spike mRNA transcript were detected by fluorescence microscopy, flow cytometry, Western blot, and real-time quantitative PCR, respectively. The results showed that the cells transfected with pEGFP-optS expressed S-EGFP fusion protein at a higher level compared with those transfected with pEGFP-S, which contains wildtype SARS-CoV spike gene sequence. The green fluorescence, mean fluorescence intensity, and SARS-CoV S RNA transcripts were found significantly reduced, and the expression of SARS-CoV S glycoprotein was strongly inhibited in those cells co-transfected with either EGFP- or S-specific siRNAs. Our findings demonstrated that the S-specific siRNAs used in this study were able to specifically and effectively inhibit SARS-CoV S glycoprotein expression in cultured cells through blocking the accumulation of S mRNA, which may provide an approach for studies on the functions of SARS-CoV S gene and development of novel prophylactic or therapeutic agents for SARS-CoV

  6. Adenovirus-Mediated Small Interfering RNA Targeting TAK1 Ameliorates Joint Inflammation with Collagen-Induced Arthritis in Mice.

    Science.gov (United States)

    Luo, Xinjing; Chen, Yongfeng; Lv, Guoju; Zhou, Zhidong; Chen, Jie; Mo, Xuanrong; Xie, Jiangwen

    2017-06-01

    Transforming growth factor β-activated kinase-1 (TAK1) is a key upstream kinase in cell signaling during inflammation, which regulates the expression of inflammatory mediators. Small interfering RNA (siRNA) against TAK1 offers promise as a potential therapeutic strategy in immune-mediated inflammatory disorder including rheumatoid arthritis. Here, we are to evaluate the therapeutic effects of intra-articular administration of adenoviral-mediated siRNA against TAK1 (ad-siRNA-TAK1) on collagen-induced arthritis (CIA) in mice. Ad-siRNA-TAK1 was constructed. The murine RAW 264.7 macrophages were infected with ad-siRNA-TAK1, and the silencing specificity of TAK1 was assessed by quantitative polymerase chain reaction (PCR) and western blot. DBA/1 mice were injected intra-articularly with ad-siRNA-TAK1. Development and severity of arthritis was assessed histologically. Synovial inflammation and bone destruction were determined by hematoxylin and eosin (HE) staining. Articular and serum concentrations of tumor necrosis factor-α, interleukin-1, and interleukin-6 were determined using enzyme-linked immunosorbent assay. Levels of phosphorylated p38, c-Jun N-terminal kinase (JNK), and extracellular-signal-regulated kinase (ERK) were detected by western blot. In vitro, ad--siRNA-TAK1 efficiently inhibited the expression of TAK1 at both mRNA and protein levels. In vivo, intra-articular injection of ad-siRNA-TAK1 efficiently alleviated joint inflammation, decreased the expression of pro-inflammatory mediators, and suppressed JNK pathways. Our results demonstrate the efficiency of ad--siRNA-TAK1 in controlling joint inflammation of CIA, which is associated with the suppression of the expression of pro-inflammatory cytokines and JNK activation.

  7. Intracerebral delivery of small interfering RNAs (siRNAs) using adenoviral vector protects mice against lethal peripheral rabies challenge.

    Science.gov (United States)

    Gupta, Praveen K; Sonwane, Arvind A; Singh, Niraj K; Meshram, Chetan D; Dahiya, Shyam S; Pawar, Sachin S; Gupta, Swatantra P; Chaturvedi, V K; Saini, Mohini

    2012-01-01

    To investigate the potential of RNA interference (RNAi) as antiviral agent against rabies, two small interfering RNAs (siRNAs) targeting rabies virus (RABV) nucleoprotein (N) and polymerase (L) genes were designed and evaluated. Both siRNAs knockdown or silenced the target RABV genes as evaluated in a plasmid based transient expression model. For efficient delivery, adenoviruses expressing the siRNAs were constructed and antiviral potential of the delivered siRNAs was investigated in BHK-21 cells. When cells treated with adenoviruses expressing siRNAs were challenged with RABV, there was 88.35±2.4% and 41.52±9.3% reduction in RABV multiplication in infected cells with siRNAs targeting RABV-N and L genes, respectively. Relative quantification of RABV transcripts using real-time PCR revealed knockdown of both RABV-N and L gene transcripts, however, significant reduction was observed only with adenovirus expressing siRNA against RABV-N. When mice treated intracerebrally with adenoviruses expressing siRNAs were challenged peripherally with lethal RABV by the intramuscular route in masseter muscle, there was 66.6% and 33.3% protection with adenoviruses expressing siRNAs against RABV-N and L genes, respectively. These results demonstrated that adenovirus expressing siRNA against RABV-N efficiently inhibited the RABV multiplication both, in vitro and in vivo and conferred significant protection against lethal RABV challenge. This supported the hypothesis that RNAi, based on siRNA targeting RABV-N gene can prevent RABV infection and holds the potential of RNAi as an approach to prevent rabies infection. Copyright © 2011 Elsevier B.V. All rights reserved.

  8. A Simple Laboratory Practical to Illustrate RNA Mediated Gene Interference Using Drosophila Cell Culture

    Science.gov (United States)

    Buluwela, Laki; Kamalati, Tahereh; Photiou, Andy; Heathcote, Dean A.; Jones, Michael D.; Ali, Simak

    2010-01-01

    RNA mediated gene interference (RNAi) is now a key tool in eukaryotic cell and molecular biology research. This article describes a five session laboratory practical, spread over a seven day period, to introduce and illustrate the technique. During the exercise, students working in small groups purify PCR products that encode "in vitro"…

  9. High frequency induction of RNA-mediated resistance against Cucumber mosaic virus using inverted repeat constructs

    NARCIS (Netherlands)

    Chen, Y.K.; Lohuis, H.; Goldbach, R.W.; Prins, M.W.

    2004-01-01

    The application of RNA-mediated resistance against Cucumber mosaic virus (CMV) by using single transgene constructs generally results in only a small portion of resistant individuals. Inverted repeat constructs encoding self-complementary double-stranded RNA have been demonstrated a potential way to

  10. AGO6 functions in RNA-mediated transcriptional gene silencing in shoot and root meristems in Arabidopsis thaliana.

    Directory of Open Access Journals (Sweden)

    Changho Eun

    Full Text Available RNA-directed DNA methylation (RdDM is a small interfering RNA (siRNA-mediated epigenetic modification that contributes to transposon silencing in plants. RdDM requires a complex transcriptional machinery that includes specialized RNA polymerases, named Pol IV and Pol V, as well as chromatin remodelling proteins, transcription factors, RNA binding proteins, and other plant-specific proteins whose functions are not yet clarified. In Arabidopsis thaliana, DICER-LIKE3 and members of the ARGONAUTE4 group of ARGONAUTE (AGO proteins are involved, respectively, in generating and using 24-nt siRNAs that trigger methylation and transcriptional gene silencing of homologous promoter sequences. AGO4 is the main AGO protein implicated in the RdDM pathway. Here we report the identification of the related AGO6 in a forward genetic screen for mutants defective in RdDM and transcriptional gene silencing in shoot and root apical meristems in Arabidopsis thaliana. The identification of AGO6, and not AGO4, in our screen is consistent with the primary expression of AGO6 in shoot and root growing points.

  11. Small interfering RNA targeting S100A4 sensitizes non-small-cell lung cancer cells (A549) to radiation treatment.

    Science.gov (United States)

    Qi, Ruixue; Qiao, Tiankui; Zhuang, Xibing

    2016-01-01

    This study aimed to investigate the impact of S100A4-small interfering RNA (S100A4-siRNA) on apoptosis and enhanced radiosensitivity in non-small-cell lung cancer (A549) cells. We also explored the mechanisms of radiosensitization and identified a new target to enhance radiosensitivity and gene therapy for non-small-cell lung cancer. RNA interference is a powerful tool for gene silencing. In this study, we constructed an effective siRNA to knock down S100A4. A549 cells were randomly divided into three groups: blank, negative control, and S100A4-siRNA. To investigate the effect of S100A4-siRNA, the expression of S100A4, E-cadherin, and p53 proteins and their messenger RNA (mRNA) was detected by Western blot and quantitative real-time polymerase chain reaction. Transwell chambers were used to assess cell invasion. Cell cycle and apoptosis were analyzed by flow cytometry. Radiosensitivity was determined by colony formation ability. Our results demonstrate that S100A4-siRNA effectively silenced the S100A4 gene. When siRNA against S100A4 was used, S100A4 protein expression was downregulated, whereas the expressions of E-cadherin and p53 were upregulated. In addition, a clear reduction in S100A4 mRNA levels was noted compared with the blank and negative control groups, whereas E-cadherin and p53 mRNA levels increased. Transfection with S100A4-siRNA significantly reduced the invasiveness of A549 cells. S100A4 silencing induced immediate G2/M arrest in cell cycle studies and increased apoptosis rates in A549 cells. In clonogenic assays, we used a multitarget, single-hit model to detect radiosensitivity after S100A4 knockdown. All parameters (D0, Dq, α, β) indicated that the downregulation of S100A4 enhanced radiosensitivity in A549 cells. Furthermore, S100A4-siRNA upregulated p53 expression, suggesting that S100A4 may promote A549 cell proliferation, invasion, and metastasis by regulating the expression of other proteins. Therefore, siRNA-directed S100A4 knockdown may

  12. Reversal of multidrug resistance by small interfering RNA (siRNA) in doxorubicin-resistant MCF-7 breast cancer cells.

    Science.gov (United States)

    Dönmez, Yaprak; Gündüz, Ufuk

    2011-03-01

    Resistance to anticancer drugs is a serious obstacle to cancer chemotherapy. A common form of multidrug resistance (MDR) is caused by the overexpression of transmembrane transporter proteins P-glycoprotein (P-gp) and multidrug resistance-associated protein-1 (MRP1), encoded by MDR1 and MRP1 genes, respectively. These proteins lead to reduced intracellular drug concentration and decreased cytotoxicity by means of their ability to pump the drugs out of the cells. Breast cancer tumor resistance is mainly associated with overexpression of P-gp/MDR1. Although some chemical MDR modulators aim to overcome MDR by interfering functioning of P-gp, their toxicities limit their usage in clinics. Consequently, RNA interference mediated sequence specific inhibition of the expression of P-gp/MDR1 mRNA may be an efficient tool to reverse MDR phenotype and increase the success of chemotherapy. Aim of this study was resensitizing doxorubicin-resistant breast cancer cells to anticancer agent doxorubicin by selective downregulation of P-gp/MDR1 mRNA. The effect of the selected MDR1 siRNA, and MRP1 expression after MDR1 silencing was determined by qPCR analysis. Intracellular drug accumulation and localization was investigated by confocal laser scanning microscopy after treatment with MDR1 siRNA. XTT cell proliferation assay was performed to determine the effect of MDR1 silencing on doxorubicin sensitivity. The results demonstrated that approximately 90% gene silencing occurred by the selected siRNA targeting MDR1 mRNA. However, the level of MRP1 mRNA did not change after MDR1 downregulation. Silencing of P-gp encoding MDR1 gene resulted in almost complete restoration of the intracellular doxorubicin accumulation and relocalization of the drug in the nuclei. Introduction of siRNA resulted in about 70% resensitization to doxorubicin. Selected siRNA duplex was shown to effectively inhibit MDR1 gene expression, restore doxorubicin accumulation and localization, and enhance

  13. Comparing artificial neural networks, general linear models and support vector machines in building predictive models for small interfering RNAs.

    Directory of Open Access Journals (Sweden)

    Kyle A McQuisten

    2009-10-01

    Full Text Available Exogenous short interfering RNAs (siRNAs induce a gene knockdown effect in cells by interacting with naturally occurring RNA processing machinery. However not all siRNAs induce this effect equally. Several heterogeneous kinds of machine learning techniques and feature sets have been applied to modeling siRNAs and their abilities to induce knockdown. There is some growing agreement to which techniques produce maximally predictive models and yet there is little consensus for methods to compare among predictive models. Also, there are few comparative studies that address what the effect of choosing learning technique, feature set or cross validation approach has on finding and discriminating among predictive models.Three learning techniques were used to develop predictive models for effective siRNA sequences including Artificial Neural Networks (ANNs, General Linear Models (GLMs and Support Vector Machines (SVMs. Five feature mapping methods were also used to generate models of siRNA activities. The 2 factors of learning technique and feature mapping were evaluated by complete 3x5 factorial ANOVA. Overall, both learning techniques and feature mapping contributed significantly to the observed variance in predictive models, but to differing degrees for precision and accuracy as well as across different kinds and levels of model cross-validation.The methods presented here provide a robust statistical framework to compare among models developed under distinct learning techniques and feature sets for siRNAs. Further comparisons among current or future modeling approaches should apply these or other suitable statistically equivalent methods to critically evaluate the performance of proposed models. ANN and GLM techniques tend to be more sensitive to the inclusion of noisy features, but the SVM technique is more robust under large numbers of features for measures of model precision and accuracy. Features found to result in maximally predictive models are

  14. Caenorhabditis elegans RIG-I Homolog Mediates Antiviral RNA Interference Downstream of Dicer-Dependent Biogenesis of Viral Small Interfering RNAs

    Directory of Open Access Journals (Sweden)

    Stephanie R. Coffman

    2017-03-01

    Full Text Available Dicer enzymes process virus-specific double-stranded RNA (dsRNA into small interfering RNAs (siRNAs to initiate specific antiviral defense by related RNA interference (RNAi pathways in plants, insects, nematodes, and mammals. Antiviral RNAi in Caenorhabditis elegans requires Dicer-related helicase 1 (DRH-1, not found in plants and insects but highly homologous to mammalian retinoic acid-inducible gene I (RIG-I-like receptors (RLRs, intracellular viral RNA sensors that trigger innate immunity against RNA virus infection. However, it remains unclear if DRH-1 acts analogously to initiate antiviral RNAi in C. elegans. Here, we performed a forward genetic screen to characterize antiviral RNAi in C. elegans. Using a mapping-by-sequencing strategy, we uncovered four loss-of-function alleles of drh-1, three of which caused mutations in the helicase and C-terminal domains conserved in RLRs. Deep sequencing of small RNAs revealed an abundant population of Dicer-dependent virus-derived small interfering RNAs (vsiRNAs in drh-1 single and double mutant animals after infection with Orsay virus, a positive-strand RNA virus. These findings provide further genetic evidence for the antiviral function of DRH-1 and illustrate that DRH-1 is not essential for the sensing and Dicer-mediated processing of the viral dsRNA replicative intermediates. Interestingly, vsiRNAs produced by drh-1 mutants were mapped overwhelmingly to the terminal regions of the viral genomic RNAs, in contrast to random distribution of vsiRNA hot spots when DRH-1 is functional. As RIG-I translocates on long dsRNA and DRH-1 exists in a complex with Dicer, we propose that DRH-1 facilitates the biogenesis of vsiRNAs in nematodes by catalyzing translocation of the Dicer complex on the viral long dsRNA precursors.

  15. Probing the Limits to MicroRNA-Mediated Control of Gene Expression.

    Directory of Open Access Journals (Sweden)

    Araks Martirosyan

    2016-01-01

    Full Text Available According to the 'ceRNA hypothesis', microRNAs (miRNAs may act as mediators of an effective positive interaction between long coding or non-coding RNA molecules, carrying significant potential implications for a variety of biological processes. Here, inspired by recent work providing a quantitative description of small regulatory elements as information-conveying channels, we characterize the effectiveness of miRNA-mediated regulation in terms of the optimal information flow achievable between modulator (transcription factors and target nodes (long RNAs. Our findings show that, while a sufficiently large degree of target derepression is needed to activate miRNA-mediated transmission, (a in case of differential mechanisms of complex processing and/or transcriptional capabilities, regulation by a post-transcriptional miRNA-channel can outperform that achieved through direct transcriptional control; moreover, (b in the presence of large populations of weakly interacting miRNA molecules the extra noise coming from titration disappears, allowing the miRNA-channel to process information as effectively as the direct channel. These observations establish the limits of miRNA-mediated post-transcriptional cross-talk and suggest that, besides providing a degree of noise buffering, this type of control may be effectively employed in cells both as a failsafe mechanism and as a preferential fine tuner of gene expression, pointing to the specific situations in which each of these functionalities is maximized.

  16. RNA-mediated epigenetic heredity requires the cytosine methyltransferase Dnmt2.

    Directory of Open Access Journals (Sweden)

    Jafar Kiani

    2013-05-01

    Full Text Available RNA-mediated transmission of phenotypes is an important way to explain non-Mendelian heredity. We have previously shown that small non-coding RNAs can induce hereditary epigenetic variations in mice and act as the transgenerational signalling molecules. Two prominent examples for these paramutations include the epigenetic modulation of the Kit gene, resulting in altered fur coloration, and the modulation of the Sox9 gene, resulting in an overgrowth phenotype. We now report that expression of the Dnmt2 RNA methyltransferase is required for the establishment and hereditary maintenance of both paramutations. Our data show that the Kit paramutant phenotype was not transmitted to the progeny of Dnmt2(-/- mice and that the Sox9 paramutation was also not established in Dnmt2(-/- embryos. Similarly, RNA from Dnmt2-negative Kit heterozygotes did not induce the paramutant phenotype when microinjected into Dnmt2-deficient fertilized eggs and microinjection of the miR-124 microRNA failed to induce the characteristic giant phenotype. In agreement with an RNA-mediated mechanism of inheritance, no change was observed in the DNA methylation profiles of the Kit locus between the wild-type and paramutant mice. RNA bisulfite sequencing confirmed Dnmt2-dependent tRNA methylation in mouse sperm and also indicated Dnmt2-dependent cytosine methylation in Kit RNA in paramutant embryos. Together, these findings uncover a novel function of Dnmt2 in RNA-mediated epigenetic heredity.

  17. The Specifics and Non-Specifics of using Small Interfering RNAs for Targeting of Viral Genes in a Fish Model

    DEFF Research Database (Denmark)

    Schyth, Brian Dall

    2007-01-01

    , and to a lesser degree naked siRNAs, primarily entered free intraperitoneal cells including macrophage-like cells. Furthermore uptake correlated with antiviral activity seen as reduced mortality of fish challenged with VHSV. Protection at the disease level was not dependent upon which one of three tested si......RNAs was used and protection correlated with up-regulation of an interferon-related gene in the liver indicating a systemic interferon response. The results show the validity of the fish model for testing delivery and non-specific effects of siRNAs in a high throughput vertebrate model. The purchase......A novel in vivo-model composed of small juvenile rainbow trout and a fish-pathogenic virus is suggested to analyze delivery and antiviral effect of formulated siRNAs. This model was used for testing delivery of intraperitoneally injected siRNAs formulated in polycationic liposomes. These...

  18. Endogenous MCM7 microRNA cluster as a novel platform to multiplex small interfering and nucleolar RNAs for combinational HIV-1 gene therapy.

    Science.gov (United States)

    Chung, Janet; Zhang, Jane; Li, Haitang; Ouellet, Dominique L; DiGiusto, David L; Rossi, John J

    2012-11-01

    Combinational therapy with small RNA inhibitory agents against multiple viral targets allows efficient inhibition of viral production by controlling gene expression at critical time points. Here we explore combinations of different classes of therapeutic anti-HIV-1 RNAs expressed from within the context of an intronic MCM7 (minichromosome maintenance complex component-7) platform that naturally harbors 3 microRNAs (miRNAs). We replaced the endogenous miRNAs with anti-HIV small RNAs, including small interfering RNAs (siRNAs) targeting HIV-1 tat and rev messages that function to induce post-transcriptional gene silencing by the RNA interference pathway, a nucleolar-localizing RNA ribozyme that targets the conserved U5 region of HIV-1 transcripts for degradation, and finally nucleolar trans-activation response (TAR) and Rev-binding element (RBE) RNA decoys designed to sequester HIV-1 Tat and Rev proteins inside the nucleolus. We demonstrate the versatility of the MCM7 platform in expressing and efficiently processing the siRNAs as miRNA mimics along with nucleolar small RNAs. Furthermore, three of the combinatorial constructs tested potently suppressed viral replication during a 1-month HIV challenge, with greater than 5-log inhibition compared with untransduced, HIV-1-infected CEM T lymphocytes. One of the most effective constructs contains an anti-HIV siRNA combined with a nucleolar-localizing U5 ribozyme and TAR decoy. This represents the first efficacious example of combining Drosha-processed siRNAs with small nucleolar ribonucleoprotein (snoRNP)-processed nucleolar RNA chimeras from a single intron platform for effective inhibition of viral replication. Moreover, we demonstrated enrichment/selection for cells expressing levels of the antiviral RNAs that provide optimal inhibition under the selective pressure of HIV. The combinations of si/snoRNAs represent a new paradigm for combinatorial RNA-based gene therapy applications.

  19. The system with zwitterionic lactose-based surfactant for complexation and delivery of small interfering ribonucleic acid—A structural and spectroscopic study

    International Nuclear Information System (INIS)

    Skupin, Michalina; Sobczak, Krzysztof; Zieliński, Ryszard; Kozak, Maciej

    2016-01-01

    Systems suitable for the effective preparation of complexes with siRNA (small interfering RNA) are at the center of interest in the area of research work on the delivery of the RNA-based drugs (RNA-therapeutics). This article presents results of a study on the structural effects associated with siRNA complexation by a surfactant comprising a lactose group (N-(3-propanesulfone)-N-dodecyl-amino-beta-D-lactose hydrochloride, LA12). The double stranded siRNA oligomer (21 base pairs) used in this study is responsible for silencing a gene that can be important in the therapy of myotonic dystrophy type 1. The obtained siRNA/LA12 lipoplexes were studied using the methods of small angle scattering of synchrotron radiation, circular dichroism spectroscopy, Fourier transform infrared spectroscopy, and electrophoretic mobility tests. Lipoplexes form in solution stable lamellar or cubic phases. The surfactant selected for the study shows much lower cytotoxicity and good complexation abilities of siRNA than dicationic or polycationic surfactants.

  20. The system with zwitterionic lactose-based surfactant for complexation and delivery of small interfering ribonucleic acid—A structural and spectroscopic study

    Science.gov (United States)

    Skupin, Michalina; Sobczak, Krzysztof; Zieliński, Ryszard; Kozak, Maciej

    2016-05-01

    Systems suitable for the effective preparation of complexes with siRNA (small interfering RNA) are at the center of interest in the area of research work on the delivery of the RNA-based drugs (RNA-therapeutics). This article presents results of a study on the structural effects associated with siRNA complexation by a surfactant comprising a lactose group (N-(3-propanesulfone)-N-dodecyl-amino-beta-D-lactose hydrochloride, LA12). The double stranded siRNA oligomer (21 base pairs) used in this study is responsible for silencing a gene that can be important in the therapy of myotonic dystrophy type 1. The obtained siRNA/LA12 lipoplexes were studied using the methods of small angle scattering of synchrotron radiation, circular dichroism spectroscopy, Fourier transform infrared spectroscopy, and electrophoretic mobility tests. Lipoplexes form in solution stable lamellar or cubic phases. The surfactant selected for the study shows much lower cytotoxicity and good complexation abilities of siRNA than dicationic or polycationic surfactants.

  1. The system with zwitterionic lactose-based surfactant for complexation and delivery of small interfering ribonucleic acid—A structural and spectroscopic study

    Energy Technology Data Exchange (ETDEWEB)

    Skupin, Michalina [Department of Macromolecular Physics, Adam Mickiewicz University, Umultowska 85, 61-614 Poznań (Poland); Sobczak, Krzysztof [Department of Gene Expression, Adam Mickiewicz University, Umultowska 89, 61-614 Poznań (Poland); Zieliński, Ryszard [Department of Technology and Instrumental Analysis, Faculty of Commodity Science, Poznań University of Economics, al. Niepodległości 10, 61-875 Poznań (Poland); Kozak, Maciej, E-mail: mkozak@amu.edu.pl [Department of Macromolecular Physics, Adam Mickiewicz University, Umultowska 85, 61-614 Poznań (Poland); Joint SAXS Laboratory, Adam Mickiewicz University, Umultowska 85, 61-614 Poznań (Poland)

    2016-05-23

    Systems suitable for the effective preparation of complexes with siRNA (small interfering RNA) are at the center of interest in the area of research work on the delivery of the RNA-based drugs (RNA-therapeutics). This article presents results of a study on the structural effects associated with siRNA complexation by a surfactant comprising a lactose group (N-(3-propanesulfone)-N-dodecyl-amino-beta-D-lactose hydrochloride, LA12). The double stranded siRNA oligomer (21 base pairs) used in this study is responsible for silencing a gene that can be important in the therapy of myotonic dystrophy type 1. The obtained siRNA/LA12 lipoplexes were studied using the methods of small angle scattering of synchrotron radiation, circular dichroism spectroscopy, Fourier transform infrared spectroscopy, and electrophoretic mobility tests. Lipoplexes form in solution stable lamellar or cubic phases. The surfactant selected for the study shows much lower cytotoxicity and good complexation abilities of siRNA than dicationic or polycationic surfactants.

  2. Arabidopsis RNASE THREE LIKE2 Modulates the Expression of Protein-Coding Genes via 24-Nucleotide Small Interfering RNA-Directed DNA Methylation.

    Science.gov (United States)

    Elvira-Matelot, Emilie; Hachet, Mélanie; Shamandi, Nahid; Comella, Pascale; Sáez-Vásquez, Julio; Zytnicki, Matthias; Vaucheret, Hervé

    2016-02-01

    RNaseIII enzymes catalyze the cleavage of double-stranded RNA (dsRNA) and have diverse functions in RNA maturation. Arabidopsis thaliana RNASE THREE LIKE2 (RTL2), which carries one RNaseIII and two dsRNA binding (DRB) domains, is a unique Arabidopsis RNaseIII enzyme resembling the budding yeast small interfering RNA (siRNA)-producing Dcr1 enzyme. Here, we show that RTL2 modulates the production of a subset of small RNAs and that this activity depends on both its RNaseIII and DRB domains. However, the mode of action of RTL2 differs from that of Dcr1. Whereas Dcr1 directly cleaves dsRNAs into 23-nucleotide siRNAs, RTL2 likely cleaves dsRNAs into longer molecules, which are subsequently processed into small RNAs by the DICER-LIKE enzymes. Depending on the dsRNA considered, RTL2-mediated maturation either improves (RTL2-dependent loci) or reduces (RTL2-sensitive loci) the production of small RNAs. Because the vast majority of RTL2-regulated loci correspond to transposons and intergenic regions producing 24-nucleotide siRNAs that guide DNA methylation, RTL2 depletion modifies DNA methylation in these regions. Nevertheless, 13% of RTL2-regulated loci correspond to protein-coding genes. We show that changes in 24-nucleotide siRNA levels also affect DNA methylation levels at such loci and inversely correlate with mRNA steady state levels, thus implicating RTL2 in the regulation of protein-coding gene expression. © 2016 American Society of Plant Biologists. All rights reserved.

  3. Satellite RNA-derived small interfering RNA satsiR-12 targeting the 3' untranslated region of Cucumber mosaic virus triggers viral RNAs for degradation.

    Science.gov (United States)

    Zhu, Hui; Duan, Cheng-Guo; Hou, Wei-Na; Du, Quan-Sheng; Lv, Dian-Qiu; Fang, Rong-Xiang; Guo, Hui-Shan

    2011-12-01

    RNA silencing provides protection against RNA viruses by targeting both the helper virus and its satellite RNA (satRNA). Virus-derived small interfering RNAs (vsiRNAs) bound with Argonaute (AGO) proteins are presumed participants in the silencing process. Here, we show that a vsiRNA targeted to virus RNAs triggers the host RNA-dependent RNA polymerase 6 (RDR6)-mediated degradation of viral RNAs. We confirmed that satRNA-derived small interfering RNAs (satsiRNAs) could be associated with different AGO proteins in planta. The most frequently cloned satsiRNA, satsiR-12, was predicted to imperfectly match to Cucumber mosaic virus (CMV) RNAs in the upstream area of the 3' untranslated region (3' UTR). Moreover, an artificial satsiR-12 (asatsiR-12) mediated cleavage of a green fluorescent protein (GFP) sensor construct harboring the satsiR-12 target site. asatsiR-12 also mediated reduction of viral RNAs in 2b-deficient CMV (CMVΔ2b)-infected Nicotiana benthamiana. The reduction was not observed in CMVΔ2b-infected RDR6i plants, in which RDR6 was silenced. Following infection with 2b-containing CMV, the reduction in viral RNAs was not observed in plants of either genotype, indicating that the asatsiR-12-mediated reduction of viral RNAs in the presence of RDR6 was inhibited by the 2b protein. Our results suggest that satsiR-12 targeting the 3' UTR of CMV RNAs triggered RDR6-dependent antiviral silencing. Competition experiments with wild-type CMV RNAs and anti-satsiR-12 mutant RNA1 in the presence of 2b and satRNA demonstrate the inhibitory effect of the 2b protein on the satsiR-12-related degradation of CMV RNAs, revealing a substantial suppressor function of the 2b protein in native CMV infection. Our data provide evidence for the important biological functions of satsiRNAs in homeostatic interactions among the host, virus, and satRNA in the final outcome of viral infection.

  4. DMPD: Negative regulation of cytoplasmic RNA-mediated antiviral signaling. [Dynamic Macrophage Pathway CSML Database

    Lifescience Database Archive (English)

    Full Text Available 18703349 Negative regulation of cytoplasmic RNA-mediated antiviral signaling. Komur...Show Negative regulation of cytoplasmic RNA-mediated antiviral signaling. PubmedID 18703349 Title Negative r...egulation of cytoplasmic RNA-mediated antiviral signaling. Authors Komuro A, Bamm

  5. Assessing delivery and quantifying efficacy of small interfering ribonucleic acid therapeutics in the skin using a dual-axis confocal microscope

    Science.gov (United States)

    Ra, Hyejun; Gonzalez-Gonzalez, Emilio; Smith, Bryan R.; Gambhir, Sanjiv S.; Kino, Gordon S.; Solgaard, Olav; Kaspar, Roger L.; Contag, Christopher H.

    2010-05-01

    Transgenic reporter mice and advances in imaging instrumentation are enabling real-time visualization of cellular mechanisms in living subjects and accelerating the development of novel therapies. Innovative confocal microscope designs are improving their utility for microscopic imaging of fluorescent reporters in living animals. We develop dual-axis confocal (DAC) microscopes for such in vivo studies and create mouse models where fluorescent proteins are expressed in the skin for the purpose of advancing skin therapeutics and transdermal delivery tools. Three-dimensional image volumes, through the different skin compartments of the epidermis and dermis, can be acquired in several seconds with the DAC microscope in living mice, and are comparable to histologic analyses of reporter protein expression patterns in skin sections. Intravital imaging with the DAC microscope further enables visualization of green fluorescent protein (GFP) reporter gene expression in the skin over time, and quantification of transdermal delivery of small interfering RNA (siRNA) and therapeutic efficacy. Visualization of transdermal delivery of nucleic acids will play an important role in the development of innovative strategies for treating skin pathologies.

  6. Topical Anti-Nuclear Factor-Kappa B Small Interfering RNA with Functional Peptides Containing Sericin-Based Hydrogel for Atopic Dermatitis

    Directory of Open Access Journals (Sweden)

    Takanori Kanazawa

    2015-09-01

    Full Text Available The small interfering RNA (siRNA is suggested to offer a novel means of treating atopic dermatitis (AD because it allows the specific silencing of genes related to AD pathogenesis. In our previous study, we found that siRNA targeted against RelA, an important nuclear factor-kappa B (NF-κB subdomain, with functional peptides, showed therapeutic effects in a mouse model of AD. In the present study, to develop a topical skin application against AD, we prepared a hydrogel containing anti-RelA siRNA and functional peptides and determined the intradermal permeation and the anti-AD effects in an AD mouse model. We selected the silk protein, sericin (SC, which is a versatile biocompatible biomaterial to prepare hydrogel as an aqueous gel base. We found that the siRNA was more widely delivered to the site of application in AD-induced ear skin of mice after topical application via the hydrogel containing functional peptides than via the preparation without functional peptides. In addition, the ear thickness and clinical skin severity of the AD-induced mice treated with hydrogel containing anti-RelA siRNA with functional peptides improved more than that of mice treated with the preparation formulated with negative siRNA.

  7. Resistance to Ditylenchus destructor Infection in Sweet Potato by the Expression of Small Interfering RNAs Targeting unc-15, a Movement-Related Gene.

    Science.gov (United States)

    Fan, Weijuan; Wei, Zhaorong; Zhang, Min; Ma, Peiyong; Liu, Guiling; Zheng, Jianli; Guo, Xiaoding; Zhang, Peng

    2015-11-01

    Stem nematode (Ditylenchus destructor) is one of most serious diseases that limit the productivity and quality of sweet potato (Ipomoea batatas), a root crop with worldwide importance for food security and nutrition improvement. Hence, there is a global demand for developing sweet potato varieties that are resistant to the disease. In this study, we have investigated the interference of stem nematode infectivity by the expression of small interfering RNAs (siRNAs) in transgenic sweet potato that are homologous to the unc-15 gene, which affects the muscle protein paramyosin of the pathogen. The production of double-stranded RNAs and siRNAs in transgenic lines with a single transgene integration event was verified by Northern blot analysis. The expression of unc-15 was reduced dramatically in stem nematodes collected from the inoculated storage roots of transgenic plants, and the infection areas of their storage roots were dramatically smaller than that of wild-type (WT). Compared with the WT, the transgenic plants showed increased yield in the stem nematode-infested field. Our results demonstrate that the expression of siRNAs targeting the unc-15 gene of D. destructor is an effective approach in improving stem nematode resistance in sweet potato, in adjunct with the global integrated pest management programs.

  8. Identification and molecular characterization of a trans-acting small interfering RNA producing locus regulating leaf rust responsive gene expression in wheat (Triticum aestivum L.).

    Science.gov (United States)

    Dutta, Summi; Kumar, Dhananjay; Jha, Shailendra; Prabhu, Kumble Vinod; Kumar, Manish; Mukhopadhyay, Kunal

    2017-11-01

    A novel leaf rust responsive ta-siRNA-producing locus was identified in wheat showing similarity to 28S rRNA and generated four differentially expressing ta-siRNAs by phasing which targeted stress responsive genes. Trans-acting-small interfering RNAs (Ta-siRNAs) are plant specific molecules generally involved in development and are also stress responsive. Ta-siRNAs identified in wheat till date are all responsive to abiotic stress only. Wheat cultivation is severely affected by rusts and leaf rust particularly affects grain filling. This study reports a novel ta-siRNA producing locus (TAS) in wheat which is a segment of 28S ribosomal RNA but shows differential expression during leaf rust infestation. Four small RNA libraries prepared from wheat Near Isogenic Lines were treated with leaf rust pathogen and compared with untreated controls. A TAS with the ability to generate four ta-siRNAs by phasing events was identified along with the microRNA TamiR16 as the phase initiator. The targets of the ta-siRNAs included α-gliadin, leucine rich repeat, trans-membrane proteins, glutathione-S-transferase, and fatty acid desaturase among others, which are either stress responsive genes or are essential for normal growth and development of plants. Expression of the TAS, its generated ta-siRNAs, and their target genes were profiled at five different time points after pathogen inoculation of susceptible and resistant wheat isolines and compared with mock-inoculated controls. Comparative analysis of expression unveiled differential and reciprocal relationship as well as discrete patterns between susceptible and resistant isolines. The expression profiles of the target genes of the identified ta-siRNAs advocate more towards effector triggered susceptibility favouring pathogenesis. The study helps in discerning the functions of wheat genes regulated by ta-siRNAs in response to leaf rust.

  9. Noise processing by microRNA-mediated circuits: The Incoherent Feed-Forward Loop, revisited

    Directory of Open Access Journals (Sweden)

    Silvia Grigolon

    2016-04-01

    Full Text Available The intrinsic stochasticity of gene expression is usually mitigated in higher eukaryotes by post-transcriptional regulation channels that stabilise the output layer, most notably protein levels. The discovery of small non-coding RNAs (miRNAs in specific motifs of the genetic regulatory network has led to identifying noise buffering as the possible key function they exert in regulation. Recent in vitro and in silico studies have corroborated this hypothesis. It is however also known that miRNA-mediated noise reduction is hampered by transcriptional bursting in simple topologies. Here, using stochastic simulations validated by analytical calculations based on van Kampen's expansion, we revisit the noise-buffering capacity of the miRNA-mediated Incoherent Feed Forward Loop (IFFL, a small module that is widespread in the gene regulatory networks of higher eukaryotes, in order to account for the effects of intermittency in the transcriptional activity of the modulator gene. We show that bursting considerably alters the circuit's ability to control static protein noise. By comparing with other regulatory architectures, we find that direct transcriptional regulation significantly outperforms the IFFL in a broad range of kinetic parameters. This suggests that, under pulsatile inputs, static noise reduction may be less important than dynamical aspects of noise and information processing in characterising the performance of regulatory elements.

  10. Small interfering RNA targeting HIF-1{alpha} reduces hypoxia-dependent transcription and radiosensitizes hypoxic HT 1080 human fibrosarcoma cells in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Staab, Adrian [Wuerzburg Univ. (Germany). Dept. of Radiation Oncology; Paul Scherrer Institute (PSI), Villigen (Switzerland); Fleischer, Markus [Wuerzburg Univ. (Germany). Dept. of Radiation Oncology; Wuerzburg Univ. (Germany). Medical Clinic II; Loeffler, Juergen; Einsele, Herrmann [Wuerzburg Univ. (Germany). Medical Clinic II; Said, Harun M.; Katzer, Astrid; Flentje, Michael [Wuerzburg Univ. (Germany). Dept. of Radiation Oncology; Plathow, Christian [Freiburg Univ. (Germany). Dept. of Nuclear Medicine; Vordermark, Dirk [Wuerzburg Univ. (Germany). Dept. of Radiation Oncology; Halle-Wittenberg Univ. (Germany). Dept. of Radiation Oncology

    2011-04-15

    Background: Hypoxia inducible factor-1 has been identified as a potential target to overcome hypoxia-induced radioresistance The aim of the present study was to investigate whether selective HIF-1 inhibition via small interfering RNA (siRNA) targeting hypoxia-inducible factor 1{alpha} (HIF-1{alpha}) affects hypoxia-induced radioresistance in HT 1080 human fibrosarcoma cells. Material and Methods: HIF-1{alpha} expression in HT 1080 human fibrosarcoma cells in vitro was silenced using HIF-1{alpha} siRNA sequence primers. Quantitative real-time polymerase chain reaction assay was performed to quantify the mRNA expression of HIF-1{alpha}. HIF-1{alpha} protein levels were studied by Western blotting at 20% (air) or after 12 hours at 0.1% O{sub 2} (hypoxia). Cells were assayed for clonogenic survival after irradiation with 2, 5, or 10 Gy, under normoxic or hypoxic conditions in the presence of HIF-1{alpha}-targeted or control siRNA sequences. A modified oxygen enhancement ratio (OER') was calculated as the ratio of the doses to achieve the same survival at 0.1% O{sub 2} as at ambient oxygen tensions. OER' was obtained at cell survival levels of 50%, 37%, and 10%. Results: HIF-1{alpha}-targeted siRNA enhanced radiation treatment efficacy under severely hypoxic conditions compared to tumor cells treated with scrambled control siRNA. OER was reduced on all survival levels after treatment with HIF-1{alpha}-targeted siRNA, suggesting that inhibition of HIF-1 activation by using HIF-1{alpha}-targeted siRNA increases radiosensitivity of hypoxic tumor cells in vitro. Conclusion: Inhibition of HIF-1 activation by using HIF-1{alpha}-targeted siRNA clearly acts synergistically with radiotherapy and increase radiosensitivity of hypoxic cells in vitro. (orig.)

  11. Small interfering RNA targeting HIF-1α reduces hypoxia-dependent transcription and radiosensitizes hypoxic HT 1080 human fibrosarcoma cells in vitro

    International Nuclear Information System (INIS)

    Staab, Adrian; Fleischer, Markus; Wuerzburg Univ.; Loeffler, Juergen; Einsele, Herrmann; Said, Harun M.; Katzer, Astrid; Flentje, Michael; Plathow, Christian; Vordermark, Dirk; Halle-Wittenberg Univ.

    2011-01-01

    Background: Hypoxia inducible factor-1 has been identified as a potential target to overcome hypoxia-induced radioresistance The aim of the present study was to investigate whether selective HIF-1 inhibition via small interfering RNA (siRNA) targeting hypoxia-inducible factor 1α (HIF-1α) affects hypoxia-induced radioresistance in HT 1080 human fibrosarcoma cells. Material and Methods: HIF-1α expression in HT 1080 human fibrosarcoma cells in vitro was silenced using HIF-1α siRNA sequence primers. Quantitative real-time polymerase chain reaction assay was performed to quantify the mRNA expression of HIF-1α. HIF-1α protein levels were studied by Western blotting at 20% (air) or after 12 hours at 0.1% O 2 (hypoxia). Cells were assayed for clonogenic survival after irradiation with 2, 5, or 10 Gy, under normoxic or hypoxic conditions in the presence of HIF-1α-targeted or control siRNA sequences. A modified oxygen enhancement ratio (OER') was calculated as the ratio of the doses to achieve the same survival at 0.1% O 2 as at ambient oxygen tensions. OER' was obtained at cell survival levels of 50%, 37%, and 10%. Results: HIF-1α-targeted siRNA enhanced radiation treatment efficacy under severely hypoxic conditions compared to tumor cells treated with scrambled control siRNA. OER was reduced on all survival levels after treatment with HIF-1α-targeted siRNA, suggesting that inhibition of HIF-1 activation by using HIF-1α-targeted siRNA increases radiosensitivity of hypoxic tumor cells in vitro. Conclusion: Inhibition of HIF-1 activation by using HIF-1α-targeted siRNA clearly acts synergistically with radiotherapy and increase radiosensitivity of hypoxic cells in vitro. (orig.)

  12. Inhibition of Hepatitis C Virus in Mice by a Small Interfering RNA Targeting a Highly Conserved Sequence in Viral IRES Pseudoknot.

    Directory of Open Access Journals (Sweden)

    Jae-Su Moon

    Full Text Available The hepatitis C virus (HCV internal ribosome entry site (IRES that directs cap-independent viral translation is a primary target for small interfering RNA (siRNA-based HCV antiviral therapy. However, identification of potent siRNAs against HCV IRES by bioinformatics-based siRNA design is a challenging task given the complexity of HCV IRES secondary and tertiary structures and association with multiple proteins, which can also dynamically change the structure of this cis-acting RNA element. In this work, we utilized siRNA tiling approach whereby siRNAs were tiled with overlapping sequences that were shifted by one or two nucleotides over the HCV IRES stem-loop structures III and IV spanning nucleotides (nts 277-343. Based on their antiviral activity, we mapped a druggable region (nts 313-343 where the targets of potent siRNAs were enriched. siIE22, which showed the greatest anti-HCV potency, targeted a highly conserved sequence across diverse HCV genotypes, locating within the IRES subdomain IIIf involved in pseudoknot formation. Stepwise target shifting toward the 5' or 3' direction by 1 or 2 nucleotides reduced the antiviral potency of siIE22, demonstrating the importance of siRNA accessibility to this highly structured and sequence-conserved region of HCV IRES for RNA interference. Nanoparticle-mediated systemic delivery of the stability-improved siIE22 derivative gs_PS1 siIE22, which contains a single phosphorothioate linkage on the guide strand, reduced the serum HCV genome titer by more than 4 log10 in a xenograft mouse model for HCV replication without generation of resistant variants. Our results provide a strategy for identifying potent siRNA species against a highly structured RNA target and offer a potential pan-HCV genotypic siRNA therapy that might be beneficial for patients resistant to current treatment regimens.

  13. Attenuation of enoyl coenzyme A hydratase 1 expression in colorectal cancer cells using small interfering RNA inhibits cell proliferation and migration.

    Science.gov (United States)

    Zhao, Qing-Mei; Kuang, Fei; Wu, Han; Zhang, Yu-Hao

    2015-07-01

    Colorectal cancer is one of the most commonly diagnosed types of cancer and is a leading cause of cancer-associated mortality worldwide. Short chain enoyl coenzyme A hydratase 1 (ECHS1) is an important gene involved in the mitochondrial fatty acid β-oxidation pathway. In addition, ECHS1 has been implicated in a variety of cancers, including breast, prostate, colon and liver cancer. The aim of the present study was to examine the expression of ECHS1 in the human HCT-8 colorectal cancer cell line. The results showed that ECHS1 expression was significantly increased in poorly-differentiated cells compared with that in well-differentiated cells. In order to further investigate the functions of ECHS1 in colorectal cancer cells, a stably transfected HCT-8 cell line expressing small interfering (si)RNA targeting the ECHS1 gene was established. The expression of the ECHS1 siRNA was found to reduce ECHS1 protein levels in ECHS1-silenced cells by >40%. Cell proliferation and cell migration of the siECHS1 cells were characterized using Cell Counting Kit-8 and Transwell assays, respectively, the results of which showed that the constitutive knockdown of the ECSH1 gene in HCT-8 cells significantly inhibited cell proliferation and migration. Furthermore, decreased levels of Akt and glycogen synthase kinase (GSK)3β phosphorylation were observed in ECHS1-silenced HCT-8 cells compared with that of parental or pU6 empty vector-transfected cells. In conclusion, the results of the present study suggested that ECHS1 may have an important role in colorectal cancer cell proliferation and migration via activation of Akt- and GSK3β-associated signaling pathways.

  14. The 21-Nucleotide, but Not 22-Nucleotide, Viral Secondary Small Interfering RNAs Direct Potent Antiviral Defense by Two Cooperative Argonautes in Arabidopsis thaliana[W][OA

    Science.gov (United States)

    Wang, Xian-Bing; Jovel, Juan; Udomporn, Petchthai; Wang, Ying; Wu, Qingfa; Li, Wan-Xiang; Gasciolli, Virginie; Vaucheret, Herve; Ding, Shou-Wei

    2011-01-01

    Arabidopsis thaliana defense against distinct positive-strand RNA viruses requires production of virus-derived secondary small interfering RNAs (siRNAs) by multiple RNA-dependent RNA polymerases. However, little is known about the biogenesis pathway and effector mechanism of viral secondary siRNAs. Here, we describe a mutant of Cucumber mosaic virus (CMV-Δ2b) that is silenced predominantly by the RNA-DEPENDENT RNA POLYMERASE6 (RDR6)-dependent viral secondary siRNA pathway. We show that production of the viral secondary siRNAs targeting CMV-Δ2b requires SUPPRESSOR OF GENE SILENCING3 and DICER-LIKE4 (DCL4) in addition to RDR6. Examination of 25 single, double, and triple mutants impaired in nine ARGONAUTE (AGO) genes combined with coimmunoprecipitation and deep sequencing identifies an essential function for AGO1 and AGO2 in defense against CMV-Δ2b, which act downstream the biogenesis of viral secondary siRNAs in a nonredundant and cooperative manner. Our findings also illustrate that dicing of the viral RNA precursors of primary and secondary siRNA is insufficient to confer virus resistance. Notably, although DCL2 is able to produce abundant viral secondary siRNAs in the absence of DCL4, the resultant 22-nucleotide viral siRNAs alone do not guide efficient silencing of CMV-Δ2b. Possible mechanisms for the observed qualitative difference in RNA silencing between 21- and 22-nucleotide secondary siRNAs are discussed. PMID:21467580

  15. Modulation of mouse coagulation gene transcription following acute in vivo delivery of synthetic small interfering RNAs targeting HNF4α and C/EBPα.

    Directory of Open Access Journals (Sweden)

    Huma Safdar

    Full Text Available Hepatocyte nuclear factor 4α (HNF4α and CCAAT/enhancer-binding protein α (C/EBPα are important for the transcriptional control of coagulation factors. To determine in vivo the direct role of HNF4α and C/EBPα in control of genes encoding coagulation factors, a synthetic small interfering (siRNA approach was used that enabled strong reduction of mouse hepatic HNF4α and C/EBPα under conditions that minimized target-related secondary effects. For both HNF4α and C/EBPα, intravenous injection of specific synthetic siRNAs (siHNF4α and siC/EBPα resulted in more than 75% reduction in their liver transcript and protein levels 2 days post-injection. For siHNF4α, this coincided with marked and significantly reduced transcript levels of the coagulation genes Hrg, Proz, Serpina5, F11, F12, F13b, Serpinf2, F5, and F9 (in order of magnitude of effect as compared to levels in control siRNA injected animals. Significant decreases in HNF4α target gene mRNA levels were also observed at 5 days post-siRNA injection, despite a limited level of HNF4α knockdown at this time point. Compared to HNF4α, C/EBPα knockdown had a modest impact on genes encoding coagulation factors. A strong reduction in C/EBPα transcript and protein levels resulted in significantly affected transcript levels of the control genes Pck1 and Fasn and a modest downregulation for coagulation genes Fba, Fbg and F5. F5 and F11 were the sole coagulation genes that were significantly affected upon prolonged (5 day C/EBPα knockdown. We conclude that in the mouse, HNF4α has a direct and essential regulatory role for multiple hepatic coagulation genes, while a role for C/EBPα is more restricted. In addition, this study demonstrates that synthetic siRNA provides a simple and fast means for determining liver transcription factor involvement in vivo.

  16. Composing Interfering Abstract Protocols

    Science.gov (United States)

    2016-04-01

    Tecnologia , Universidade Nova de Lisboa, Caparica, Portugal. This document is a companion technical report of the paper, “Composing Interfering Abstract...a Ciência e Tecnologia (Portuguese Foundation for Science and Technology) through the Carnegie Mellon Portugal Program under grant SFRH / BD / 33765

  17. sRNA-Mediated Regulation of P-Fimbriae Phase Variation in Uropathogenic Escherichia coli

    DEFF Research Database (Denmark)

    Khandige, Surabhi; Kronborg, Tina; Uhlin, Bernt Eric

    2015-01-01

    to the discovery of a novel virulence-associated trans-acting sRNA-PapR. Deletion of papR was found to enhance adhesion of UTI89 to both bladder and kidney cell lines in a manner independent of type-1 fimbriae. We demonstrate PapR mediated posttranscriptional repression of the P-fimbriae phase regulator gene pap......Uropathogenic Escherichia coli (UPEC) are capable of occupying physiologically distinct intracellular and extracellular niches within the urinary tract. This feat requires the timely regulation of gene expression and small RNAs (sRNAs) are known to mediate such rapid adjustments in response...... to changing environmental cues. This study aimed to uncover sRNA-mediated gene regulation in the UPEC strain UTI89, during infection of bladder epithelial cells. Hfq is an RNA chaperone known to facilitate and stabilize sRNA and target mRNA interactions with bacterial cells. The co...

  18. Shock-induced poration, cholesterol flip-flop and small interfering RNA transfection in a phospholipid membrane: Multimillion atom, microsecond molecular dynamics simulations

    Science.gov (United States)

    Choubey, Amit

    performing a 15 mus all-atom MD simulation of a DPPC-CHOL bilayer. We find that the CHOL flip-flop rates are on the sub microsecond timescale. These results are verified by performing various independent parallel replica (PR) simulations. Our PR simulations provide significant boost in sampling of the flip-flop events. We observe that the CHOL flip-flop can induce membrane order, regulate membrane-bending energy, and facilitate membrane relaxation. The rapid flip-flop rates reported here have important implications for the role of CHOL in mechanical properties of cell membranes, formation of domains, and maintaining CHOL concentration asymmetry in plasma membrane. Our PR approach can reach submillisecond time scales and bridge the gap between MD simulations and Nuclear Magnetic Resonance (NMR) experiments on CHOL flip-flop dynamics in membranes. The last project deals with transfection barriers encountered by a bare small interfering RNA (siRNA) in a phospholipid bilayer. SiRNA molecules play a pivotal role in therapeutic applications. A key limitation to the widespread implementation of siRNA-based therapeutics is the difficulty of delivering siRNA-based drugs to cells. We have examined structural and mechanical barriers to siRNA passage across a phospholipid bilayer using all-atom MD simulations. We find that the electrostatic interaction between the anionic siRNA and head groups of phospholipid molecules induces a phase transformation from the liquid crystalline to ripple phase. Steered MD simulations reveal that the siRNA transfection through the ripple phase requires a force of ˜ 1.5 nN.

  19. MicroRNA-Mediated Reprogramming of Somatic Cells into Neural Stem Cells or Neurons.

    Science.gov (United States)

    Yang, Hao; Zhang, Lingling; An, Jing; Zhang, Qian; Liu, Cuicui; He, Baorong; Hao, Ding-Jun

    2017-03-01

    Cellular reprogramming is a promising strategy to generate neural stem cells (NSCs) or desired subtype-specific neurons for cell-based therapeutic intervention. By far, the intricate cell event like reprogramming of non-neural cells to desired cell types can be achieved by forced expression of lineage-related transcription factors (TFs), nuclear transfer, a defined set of factors, and via non-coding microRNAs (miRNAs), as well as other precisely defined conditions. In addition, scientists have been trying to develop better approaches for reprogramming, either by using distinct combinations of a set of small molecules and certain TFs or delivery of appropriate small molecules and miRNAs. The miRNA-mediated approach is fascinating because of its potential to rapidly generate a variety of therapeutically desired cell types from other cell lineages. Recent studies have made great progress in miRNA-mediated neural reprogramming of somatic cells to various specific neuronal subtypes with more efficiency even though the exact mechanisms remain to be further explored. Based on key roles of miRNAs in neural reprogramming across differentiated cell lineages, it is of vital interest to summarize the recent knowledge regarding the instructive role of miRNAs in direct conversion of somatic cells into neural lineages. This precise review mainly focuses on recent discoveries of miRNAs functions in initiating cell reprogramming and fate specification of the neuronal subtype. Moreover, we discuss most recent findings about some miRNAs' activity in regulating various developmental stages of neurons, which is helpful for understanding the event network between miRNAs and their targets.

  20. Correction of Mutant p63 in EEC Syndrome Using siRNA Mediated Allele-Specific Silencing Restores Defective Stem Cell Function.

    Science.gov (United States)

    Barbaro, Vanessa; Nasti, Annamaria A; Del Vecchio, Claudia; Ferrari, Stefano; Migliorati, Angelo; Raffa, Paolo; Lariccia, Vincenzo; Nespeca, Patrizia; Biasolo, Mariangela; Willoughby, Colin E; Ponzin, Diego; Palù, Giorgio; Parolin, Cristina; Di Iorio, Enzo

    2016-06-01

    Ectrodactyly-Ectodermal dysplasia-Clefting (EEC) syndrome is a rare autosomal dominant disease caused by heterozygous mutations in the p63 gene and characterized by limb defects, orofacial clefting, ectodermal dysplasia, and ocular defects. Patients develop progressive total bilateral limbal stem cell deficiency, which eventually results in corneal blindness. Medical and surgical treatments are ineffective and of limited benefit. Oral mucosa epithelial stem cells (OMESCs) represent an alternative source of stem cells capable of regenerating the corneal epithelium and, combined with gene therapy, could provide an attractive therapeutic avenue. OMESCs from EEC patients carrying the most severe p63 mutations (p.R279H and p.R304Q) were characterized and the genetic defect of p.R279H silenced using allele-specific (AS) small interfering RNAs (siRNAs). Systematic screening of locked nucleic acid (LNA)-siRNAs against R279H-p63 allele in (i) stable WT-ΔNp63α-RFP and R279H-ΔNp63α-EGFP cell lines, (ii) transient doubly transfected cell lines, and (iii) p.R279H OMESCs, identified a number of potent siRNA inhibitors for the mutant allele, which had no effect on wild-type p63. In addition, siRNA treatment led to longer acquired life span of mutated stem cells compared to controls, less accelerated stem cell differentiation in vitro, reduced proliferation properties, and effective ability in correcting the epithelial hypoplasia, thus giving rise to full thickness stratified and differentiated epithelia. This study demonstrates the phenotypic correction of mutant stem cells (OMESCs) in EEC syndrome by means of siRNA mediated AS silencing with restoration of function. The application of siRNA, alone or in combination with cell-based therapies, offers a therapeutic strategy for corneal blindness in EEC syndrome. Stem Cells 2016;34:1588-1600. © 2016 AlphaMed Press.

  1. Roles of Prolyl Isomerases in RNA-Mediated Gene Expression

    Directory of Open Access Journals (Sweden)

    Roopa Thapar

    2015-05-01

    Full Text Available The peptidyl-prolyl cis-trans isomerases (PPIases that include immunophilins (cyclophilins and FKBPs and parvulins (Pin1, Par14, Par17 participate in cell signaling, transcription, pre-mRNA processing and mRNA decay. The human genome encodes 19 cyclophilins, 18 FKBPs and three parvulins. Immunophilins are receptors for the immunosuppressive drugs cyclosporin A, FK506, and rapamycin that are used in organ transplantation. Pin1 has also been targeted in the treatment of Alzheimer’s disease, asthma, and a number of cancers. While these PPIases are characterized as molecular chaperones, they also act in a nonchaperone manner to promote protein-protein interactions using surfaces outside their active sites. The immunosuppressive drugs act by a gain-of-function mechanism by promoting protein-protein interactions in vivo. Several immunophilins have been identified as components of the spliceosome and are essential for alternative splicing. Pin1 plays roles in transcription and RNA processing by catalyzing conformational changes in the RNA Pol II C-terminal domain. Pin1 also binds several RNA binding proteins such as AUF1, KSRP, HuR, and SLBP that regulate mRNA decay by remodeling mRNP complexes. The functions of ribonucleoprotein associated PPIases are largely unknown. This review highlights PPIases that play roles in RNA-mediated gene expression, providing insight into their structures, functions and mechanisms of action in mRNP remodeling in vivo.

  2. Long non‑coding RNA BC168687 small interfering RNA reduces high glucose and high free fatty acid‑induced expression of P2X7 receptors in satellite glial cells.

    Science.gov (United States)

    Liu, Cheng-Long; Deng, Ze-Yu; Du, Er-Rong; Xu, Chang-Shui

    2018-04-01

    Purinergic signaling contributes to inflammatory and immune responses. The activation of the P2X purinoceptor 7 (P2X7) in satellite glial cells (SGCs) may be an essential component in the promotion of inflammation and neuropathic pain. Long non‑coding RNAs (lncRNAs) are involved in multiple physiological and pathological processes. The aim of the present study was to investigate the effects of a small interfering RNA for the lncRNA BC168687 on SGC P2X7 expression in a high glucose and high free fatty acids (HGHF) environment. It was demonstrated that BC168687 small interfering (si)RNA downregulated the co‑expression of the P2X7 and glial fibrillary acidic protein and P2X7 mRNA expression. Additionally, HGHF may activate the mitogen‑activated protein kinase signaling pathway by increasing the release of nitric oxide and reactive oxygen species in SGCs. Taken together, these results indicate that silencing BC168687 expression may downregulate the increased expression of P2X7 receptors in SGCs induced by a HGHF environment.

  3. Small interfering RNA targeted to IGF-IR delays tumor growth and induces proinflammatory cytokines in a mouse breast cancer model.

    Directory of Open Access Journals (Sweden)

    Tiphanie Durfort

    Full Text Available Insulin-like growth factor I (IGF-I and its type I receptor (IGF-IR play significant roles in tumorigenesis and in immune response. Here, we wanted to know whether an RNA interference approach targeted to IGF-IR could be used for specific antitumor immunostimulation in a breast cancer model. For that, we evaluated short interfering RNA (siRNAs for inhibition of in vivo tumor growth and immunological stimulation in immunocompetent mice. We designed 2'-O-methyl-modified siRNAs to inhibit expression of IGF-IR in two murine breast cancer cell lines (EMT6, C4HD. Cell transfection of IGF-IR siRNAs decreased proliferation, diminished phosphorylation of downstream signaling pathway proteins, AKT and ERK, and caused a G0/G1 cell cycle block. The IGF-IR silencing also induced secretion of two proinflammatory cytokines, TNF- α and IFN-γ. When we transfected C4HD cells with siRNAs targeting IGF-IR, mammary tumor growth was strongly delayed in syngenic mice. Histology of developing tumors in mice grafted with IGF-IR siRNA treated C4HD cells revealed a low mitotic index, and infiltration of lymphocytes and polymorphonuclear neutrophils, suggesting activation of an antitumor immune response. When we used C4HD cells treated with siRNA as an immunogen, we observed an increase in delayed-type hypersensitivity and the presence of cytotoxic splenocytes against wild-type C4HD cells, indicative of evolving immune response. Our findings show that silencing IGF-IR using synthetic siRNA bearing 2'-O-methyl nucleotides may offer a new clinical approach for treatment of mammary tumors expressing IGF-IR. Interestingly, our work also suggests that crosstalk between IGF-I axis and antitumor immune response can mobilize proinflammatory cytokines.

  4. MicroRNA-mediated networks underlie immune response regulation in papillary thyroid carcinoma

    Science.gov (United States)

    Huang, Chen-Tsung; Oyang, Yen-Jen; Huang, Hsuan-Cheng; Juan, Hsueh-Fen

    2014-09-01

    Papillary thyroid carcinoma (PTC) is a common endocrine malignancy with low death rate but increased incidence and recurrence in recent years. MicroRNAs (miRNAs) are small non-coding RNAs with diverse regulatory capacities in eukaryotes and have been frequently implied in human cancer. Despite current progress, however, a panoramic overview concerning miRNA regulatory networks in PTC is still lacking. Here, we analyzed the expression datasets of PTC from The Cancer Genome Atlas (TCGA) Data Portal and demonstrate for the first time that immune responses are significantly enriched and under specific regulation in the direct miRNA-target network among distinctive PTC variants to different extents. Additionally, considering the unconventional properties of miRNAs, we explore the protein-coding competing endogenous RNA (ceRNA) and the modulatory networks in PTC and unexpectedly disclose concerted regulation of immune responses from these networks. Interestingly, miRNAs from these conventional and unconventional networks share general similarities and differences but tend to be disparate as regulatory activities increase, coordinately tuning the immune responses that in part account for PTC tumor biology. Together, our systematic results uncover the intensive regulation of immune responses underlain by miRNA-mediated networks in PTC, opening up new avenues in the management of thyroid cancer.

  5. Small Interfering RNA Specific for N-Methyl-D-Aspartate Receptor 2B Offers Neuroprotection to Dopamine Neurons through Activation of MAP Kinase

    Directory of Open Access Journals (Sweden)

    Olivia T.W. Ng

    2012-02-01

    Full Text Available In the present study, N-methyl-D-aspartate receptor 2B (NR2B-specific siRNA was applied in parkinsonian models. Our previous results showed that reduction in expression of N-methyl-D-aspartate receptor 1 (NR1, the key subunit of N-methyl-D-aspartate receptors, by antisense oligos amelio-rated the motor symptoms in the 6-hydroxydopamine (6-OHDA-lesioned rat, an animal model of Parkinson's disease (PD [Lai et al.: Neurochem Int 2004;45:11-22]. To further the investigation on the efficacy of gene silencing, small interference RNA (siRNA specific for the NR2B subunit was designed and administered in the striatum of 6-OHDA-lesioned rats. The present results show that administration of NR2B-specific siRNA decreased the number of apomorphine-induced rotations in the lesioned rats and that there was a significant reduction in NR2B proteins levels after NR2B-specific siRNA administration. Furthermore, attenuation of the loss of dopaminergic neurons was found in both the striatal and substantia nigra regions of the 6-OHDA-lesioned rats that had been continuously infused with siRNA for 7 days. In addition, a significant upregulation of p-p44/42 MAPK (ERK1/2; Thr202/Tyr204 and p-CREB (Ser133 in striatal neurons was found. These results suggest that application of the gene silencing targeting NR2B could be a potential treatment of PD, and they also revealed the possibility of NR2B-specific siRNA being involved in the prosurvival pathway.

  6. sRNA-Mediated Regulation of P-Fimbriae Phase Variation in Uropathogenic Escherichia coli.

    Directory of Open Access Journals (Sweden)

    Surabhi Khandige

    2015-08-01

    Full Text Available Uropathogenic Escherichia coli (UPEC are capable of occupying physiologically distinct intracellular and extracellular niches within the urinary tract. This feat requires the timely regulation of gene expression and small RNAs (sRNAs are known to mediate such rapid adjustments in response to changing environmental cues. This study aimed to uncover sRNA-mediated gene regulation in the UPEC strain UTI89, during infection of bladder epithelial cells. Hfq is an RNA chaperone known to facilitate and stabilize sRNA and target mRNA interactions with bacterial cells. The co-immunoprecipitation and high throughput RNA sequencing of Hfq bound sRNAs performed in this study, revealed distinct sRNA profiles in UPEC in the extracellular and intracellular environments. Our findings emphasize the importance of studying regulatory sRNAs in a biologically relevant niche. This strategy also led to the discovery of a novel virulence-associated trans-acting sRNA-PapR. Deletion of papR was found to enhance adhesion of UTI89 to both bladder and kidney cell lines in a manner independent of type-1 fimbriae. We demonstrate PapR mediated posttranscriptional repression of the P-fimbriae phase regulator gene papI and postulate a role for such regulation in fimbrial cross-talk at the population level in UPEC. Our results further implicate the Leucine responsive protein (LRP as a transcriptional activator regulating PapR expression. Our study reports, for the first time, a role for sRNAs in regulation of P-fimbriae phase variation and emphasizes the importance of studying pathogenesis-specific sRNAs within a relevant biological niche.

  7. Adenovirus Vector-Derived VA-RNA-Mediated Innate Immune Responses

    Directory of Open Access Journals (Sweden)

    Hiroyuki Mizuguchi

    2011-07-01

    Full Text Available The major limitation of the clinical use of replication-incompetent adenovirus (Ad vectors is the interference by innate immune responses, including induction of inflammatory cytokines and interferons (IFN, following in vivo application of Ad vectors. Ad vector-induced production of inflammatory cytokines and IFNs also results in severe organ damage and efficient induction of acquired immune responses against Ad proteins and transgene products. Ad vector-induced innate immune responses are triggered by the recognition of Ad components by pattern recognition receptors (PRRs. In order to reduce the side effects by Ad vector-induced innate immune responses and to develop safer Ad vectors, it is crucial to clarify which PRRs and which Ad components are involved in Ad vector-induced innate immune responses. Our group previously demonstrated that myeloid differentiating factor 88 (MyD88 and toll-like receptor 9 (TLR9 play crucial roles in the Ad vector-induced inflammatory cytokine production in mouse bone marrow-derived dendritic cells. Furthermore, our group recently found that virus associated-RNAs (VA-RNAs, which are about 160 nucleotide-long non-coding small RNAs encoded in the Ad genome, are involved in IFN production through the IFN-β promoter stimulator-1 (IPS-1-mediated signaling pathway following Ad vector transduction. The aim of this review is to highlight the Ad vector-induced innate immune responses following transduction, especially VA-RNA-mediated innate immune responses. Our findings on the mechanism of Ad vector-induced innate immune responses should make an important contribution to the development of safer Ad vectors, such as an Ad vector lacking expression of VA-RNAs.

  8. Interfering with bacterial gossip

    DEFF Research Database (Denmark)

    Bjarnsholt, Thomas; Tolker-Nielsen, Tim; Givskov, Michael

    2011-01-01

    Biofilm resilience poses major challenges to the development of novel antimicrobial agents. Biofilm bacteria can be considered small groups of “Special Forces” capable of infiltrating the host and destroying important components of the cellular defense system with the aim of crippling the host...... defense. Antibiotics exhibit a rather limited effect on biofilms. Furthermore, antibiotics have an ‘inherent obsolescence’ because they select for development of resistance. Bacterial infections with origin in bacterial biofilms have become a serious threat in developed countries. Pseudomonas aeruginosa...... that appropriately target bacteria in their relevant habitat with the aim of mitigating their destructive impact on patients. In this review we describe molecular mechanisms involved in “bacterial gossip” (more scientifically referred to as quorum sensing (QS) and c-di-GMP signaling), virulence, biofilm formation...

  9. Silencing expression of the catalytic subunit of DNA-dependent protein kinase by small interfering RNA sensitizes human cells for radiation-induced chromosome damage, cell killing, and mutation

    Science.gov (United States)

    Peng, Yuanlin; Zhang, Qinming; Nagasawa, Hatsumi; Okayasu, Ryuichi; Liber, Howard L.; Bedford, Joel S.

    2002-01-01

    Targeted gene silencing in mammalian cells by RNA interference (RNAi) using small interfering RNAs (siRNAs) was recently described by Elbashir et al. (S. M. Elbashir et al., Nature (Lond.), 411: 494-498, 2001). We have used this methodology in several human cell strains to reduce expression of the Prkdc (DNA-PKcs) gene coding for the catalytic subunit of the DNA-dependent protein kinase (DNA-PKcs) that is involved in the nonhomologous end joining of DNA double-strand breaks. We have also demonstrated a radiosensitization for several phenotypic endpoints of radiation damage. In low-passage normal human fibroblasts, siRNA knock-down of DNA-PKcs resulted in a reduced capacity for restitution of radiation-induced interphase chromosome breaks as measured by premature chromosome condensation, an increased yield of acentric chromosome fragments at the first postirradiation mitosis, and an increased radiosensitivity for cell killing. For three strains of related human lymphoblasts, DNA-PKcs-targeted siRNA transfection resulted in little or no increase in radiosensitivity with respect to cell killing, a 1.5-fold decrease in induced mutant yield in TK6- and p53-null NH32 cells, but about a 2-fold increase in induced mutant yield in p53-mutant WTK1 cells at both the hypoxanthine quanine phosphoribosyl transferase (hprt) and the thymidine kinase loci.

  10. Analysis of the siRNA-Mediated Gene Silencing Process Targeting Three Homologous Genes Controlling Soybean Seed Oil Quality.

    Directory of Open Access Journals (Sweden)

    Sha Lu

    Full Text Available In the past decade, RNA silencing has gained significant attention because of its success in genomic scale research and also in the genetic improvement of crop plants. However, little is known about the molecular basis of siRNA processing in association with its target transcript. To reveal this process for improving hpRNA-mediated gene silencing in crop plants, the soybean GmFAD3 gene family was chosen as a test model. We analyzed RNAi mutant soybean lines in which three members of the GmFAD3 gene family were silenced. The silencing levels of FAD3A, FAD3B and FAD3C were correlated with the degrees of sequence homology between the inverted repeat of hpRNA and the GmFAD3 transcripts in the RNAi lines. Strikingly, transgenes in two of the three RNAi lines were heavily methylated, leading to a dramatic reduction of hpRNA-derived siRNAs. Small RNAs corresponding to the loop portion of the hairpin transcript were detected while much lower levels of siRNAs were found outside of the target region. siRNAs generated from the 318-bp inverted repeat were found to be diced much more frequently at stem sequences close to the loop and associated with the inferred cleavage sites on the target transcripts, manifesting "hot spots". The top candidate hpRNA-derived siRNA share certain sequence features with mature miRNA. This is the first comprehensive and detailed study revealing the siRNA-mediated gene silencing mechanism in crop plants using gene family GmFAD3 as a test model.

  11. Analysis of the siRNA-Mediated Gene Silencing Process Targeting Three Homologous Genes Controlling Soybean Seed Oil Quality.

    Science.gov (United States)

    Lu, Sha; Yin, Xiaoyan; Spollen, William; Zhang, Ning; Xu, Dong; Schoelz, James; Bilyeu, Kristin; Zhang, Zhanyuan J

    2015-01-01

    In the past decade, RNA silencing has gained significant attention because of its success in genomic scale research and also in the genetic improvement of crop plants. However, little is known about the molecular basis of siRNA processing in association with its target transcript. To reveal this process for improving hpRNA-mediated gene silencing in crop plants, the soybean GmFAD3 gene family was chosen as a test model. We analyzed RNAi mutant soybean lines in which three members of the GmFAD3 gene family were silenced. The silencing levels of FAD3A, FAD3B and FAD3C were correlated with the degrees of sequence homology between the inverted repeat of hpRNA and the GmFAD3 transcripts in the RNAi lines. Strikingly, transgenes in two of the three RNAi lines were heavily methylated, leading to a dramatic reduction of hpRNA-derived siRNAs. Small RNAs corresponding to the loop portion of the hairpin transcript were detected while much lower levels of siRNAs were found outside of the target region. siRNAs generated from the 318-bp inverted repeat were found to be diced much more frequently at stem sequences close to the loop and associated with the inferred cleavage sites on the target transcripts, manifesting "hot spots". The top candidate hpRNA-derived siRNA share certain sequence features with mature miRNA. This is the first comprehensive and detailed study revealing the siRNA-mediated gene silencing mechanism in crop plants using gene family GmFAD3 as a test model.

  12. MicroRNA-Mediated Gene Silencing in Plant Defense and Viral Counter-Defense.

    Science.gov (United States)

    Liu, Sheng-Rui; Zhou, Jing-Jing; Hu, Chun-Gen; Wei, Chao-Ling; Zhang, Jin-Zhi

    2017-01-01

    MicroRNAs (miRNAs) are non-coding RNAs of approximately 20-24 nucleotides in length that serve as central regulators of eukaryotic gene expression by targeting mRNAs for cleavage or translational repression. In plants, miRNAs are associated with numerous regulatory pathways in growth and development processes, and defensive responses in plant-pathogen interactions. Recently, significant progress has been made in understanding miRNA-mediated gene silencing and how viruses counter this defense mechanism. Here, we summarize the current knowledge and recent advances in understanding the roles of miRNAs involved in the plant defense against viruses and viral counter-defense. We also document the application of miRNAs in plant antiviral defense. This review discusses the current understanding of the mechanisms of miRNA-mediated gene silencing and provides insights on the never-ending arms race between plants and viruses.

  13. MicroRNA-Mediated Gene Silencing in Plant Defense and Viral Counter-Defense

    OpenAIRE

    Liu, Sheng-Rui; Zhou, Jing-Jing; Hu, Chun-Gen; Wei, Chao-Ling; Zhang, Jin-Zhi

    2017-01-01

    MicroRNAs (miRNAs) are non-coding RNAs of approximately 20–24 nucleotides in length that serve as central regulators of eukaryotic gene expression by targeting mRNAs for cleavage or translational repression. In plants, miRNAs are associated with numerous regulatory pathways in growth and development processes, and defensive responses in plant–pathogen interactions. Recently, significant progress has been made in understanding miRNA-mediated gene silencing and how viruses counter this defense ...

  14. The role of RNA structure at 5' untranslated region in microRNA-mediated gene regulation.

    Science.gov (United States)

    Gu, Wanjun; Xu, Yuming; Xie, Xueying; Wang, Ting; Ko, Jae-Hong; Zhou, Tong

    2014-09-01

    Recent studies have suggested that the secondary structure of the 5' untranslated region (5' UTR) of messenger RNA (mRNA) is important for microRNA (miRNA)-mediated gene regulation in humans. mRNAs that are targeted by miRNA tend to have a higher degree of local secondary structure in their 5' UTR; however, the general role of the 5' UTR in miRNA-mediated gene regulation remains unknown. We systematically surveyed the secondary structure of 5' UTRs in both plant and animal species and found a universal trend of increased mRNA stability near the 5' cap in mRNAs that are regulated by miRNA in animals, but not in plants. Intra-genome comparison showed that gene expression level, GC content of the 5' UTR, number of miRNA target sites, and 5' UTR length may influence mRNA structure near the 5' cap. Our results suggest that the 5' UTR secondary structure performs multiple functions in regulating post-transcriptional processes. Although the local structure immediately upstream of the start codon is involved in translation initiation, RNA structure near the 5' cap site, rather than the structure of the full-length 5' UTR sequences, plays an important role in miRNA-mediated gene regulation. © 2014 Gu et al.; Published by Cold Spring Harbor Laboratory Press for the RNA Society.

  15. Integrative analyses reveal a long noncoding RNA-mediated sponge regulatory network in prostate cancer.

    Science.gov (United States)

    Du, Zhou; Sun, Tong; Hacisuleyman, Ezgi; Fei, Teng; Wang, Xiaodong; Brown, Myles; Rinn, John L; Lee, Mary Gwo-Shu; Chen, Yiwen; Kantoff, Philip W; Liu, X Shirley

    2016-03-15

    Mounting evidence suggests that long noncoding RNAs (lncRNAs) can function as microRNA sponges and compete for microRNA binding to protein-coding transcripts. However, the prevalence, functional significance and targets of lncRNA-mediated sponge regulation of cancer are mostly unknown. Here we identify a lncRNA-mediated sponge regulatory network that affects the expression of many protein-coding prostate cancer driver genes, by integrating analysis of sequence features and gene expression profiles of both lncRNAs and protein-coding genes in tumours. We confirm the tumour-suppressive function of two lncRNAs (TUG1 and CTB-89H12.4) and their regulation of PTEN expression in prostate cancer. Surprisingly, one of the two lncRNAs, TUG1, was previously known for its function in polycomb repressive complex 2 (PRC2)-mediated transcriptional regulation, suggesting its sub-cellular localization-dependent function. Our findings not only suggest an important role of lncRNA-mediated sponge regulation in cancer, but also underscore the critical influence of cytoplasmic localization on the efficacy of a sponge lncRNA.

  16. Recombinant adeno-associated virus-, polyethylenimine/plasmid- and lipofectamine/carboxyfluorescein-labeled small interfering RNA-based transfection in retinal pigment epithelial cells with ultrasound and/or SonoVue.

    Science.gov (United States)

    Li, Hongli; Wan, Caifeng; Li, Fenghua

    2015-05-01

    The present study was conducted to investigate the efficacy and safety of ultrasound (US)‑mediated transfection of the type 2 recombinant adeno‑associated virus (AAV) vectors encoding the enhanced green fluorescent protein (EGFP) gene (rAAV), polyethylenimine (PEI)/plasmid EGFP‑N1 (pDNA) or lipofectamine (L)/carboxyfluorescein (FAM)‑labeled small interfering RNA (siRNA) in the human ARPE‑19 retinal pigment epithelial (RPE) cell line, with or without the addition of SonoVue. Cultured RPE cells were exposed to US, with or without SonoVue under different conditions, including variation in the intensity and duration of treatment, and the dose of microbubbles. The effects of ultrasound‑targeted microbubble destruction (UTMD) on the structure of pDNA and the transfection ability of rAAV, PEI/pDNA and L/siRNA were also evaluated. Furthermore, the effect of UTMD on RPE cells was evaluated at 0 and 24 h following UTMD. US‑mediated transfection (USMT) significantly increased L/siRNA transfection efficiency, as measured by the transgene expression per cell and the percentage of transfected cells. UTMD significantly increased rAAV and PEI/pDNA transfer to RPE cells. UTMD‑mediated rAAV or PEI/pDNA delivery was more effective than USMT‑mediated delivery of siRNA. Evaluating cell viability at 24 h post‑UTMD provided more valuable information than immediate evaluation following UTMD. Furthermore, there was minimal cytotoxicity and minimal change to the structure of pDNA under the optimal parameters. UTMD/US may be of use in enhancing rAAV, PEI/pDNA and L/siRNA transgene expression of ARPE‑19 cells in vitro. Studies on the transfection of different nucleotides (such as pDNA and siRNA) and different types of vectors (chemical and biological) mediated by UTMD may provide useful information to guide future in vivo and transfection studies.

  17. Engineering of small interfering RNA-loaded lipidoid-poly(DL-lactic-co-glycolic acid) hybrid nanoparticles for highly efficient and safe gene silencing: A quality by design-based approach.

    Science.gov (United States)

    Thanki, Kaushik; Zeng, Xianghui; Justesen, Sarah; Tejlmann, Sarah; Falkenberg, Emily; Van Driessche, Elize; Mørck Nielsen, Hanne; Franzyk, Henrik; Foged, Camilla

    2017-11-01

    Safety and efficacy of therapeutics based on RNA interference, e.g., small interfering RNA (siRNA), are dependent on the optimal engineering of the delivery technology, which is used for intracellular delivery of siRNA to the cytosol of target cells. We investigated the hypothesis that commonly used and poorly tolerated cationic lipids might be replaced with more efficacious and safe lipidoids as the lipid component of siRNA-loaded lipid-polymer hybrid nanoparticles (LPNs) for achieving more efficient gene silencing at lower and safer doses. However, formulation design of such a complex formulation is highly challenging due to a strong interplay between several contributing factors. Hence, critical formulation variables, i.e. the lipidoid content and siRNA:lipidoid ratio, were initially identified, followed by a systematic quality-by-design approach to define the optimal operating space (OOS), eventually resulting in the identification of a robust, highly efficacious and safe formulation. A 17-run design of experiment with an I-optimal approach was performed to systematically assess the effect of selected variables on critical quality attributes (CQAs), i.e. physicochemical properties (hydrodynamic size, zeta potential, siRNA encapsulation/loading) and the biological performance (in vitro gene silencing and cell viability). Model fitting of the obtained data to construct predictive models revealed non-linear relationships for all CQAs, which can be readily overlooked in one-factor-at-a-time optimization approaches. The response surface methodology further enabled the identification of an OOS that met the desired quality target product profile. The optimized lipidoid-modified LPNs revealed more than 50-fold higher in vitro gene silencing at well-tolerated doses and approx. a twofold increase in siRNA loading as compared to reference LPNs modified with the commonly used cationic lipid dioleyltrimethylammonium propane (DOTAP). Thus, lipidoid-modified LPNs show highly

  18. siRNA-mediated knockdown against CDCA1 and KNTC2, both frequently overexpressed in colorectal and gastric cancers, suppresses cell proliferation and induces apoptosis

    Energy Technology Data Exchange (ETDEWEB)

    Kaneko, Naoyuki [Department of Molecular Pathology, Tohoku University School of Medicine, Sendai, Miyagi 980-8575 (Japan); Department of Surgery, Tohoku University School of Medicine, Sendai, Miyagi 980-8575 (Japan); Miura, Koh [Department of Surgery, Tohoku University School of Medicine, Sendai, Miyagi 980-8575 (Japan); Gu, Zhaodi [Department of Molecular Pathology, Tohoku University School of Medicine, Sendai, Miyagi 980-8575 (Japan); Karasawa, Hideaki; Ohnuma, Shinobu; Sasaki, Hiroyuki [Department of Surgery, Tohoku University School of Medicine, Sendai, Miyagi 980-8575 (Japan); Tsukamoto, Nobukazu; Yokoyama, Satoru; Yamamura, Akihiro [Department of Molecular Pathology, Tohoku University School of Medicine, Sendai, Miyagi 980-8575 (Japan); Department of Surgery, Tohoku University School of Medicine, Sendai, Miyagi 980-8575 (Japan); Nagase, Hiroki [Division of Cancer Genetics, Department of Advanced Medical Science, Nihon University School of Medicine, Itabashi-ku, Tokyo 173-8610 (Japan); Shibata, Chikashi; Sasaki, Iwao [Department of Surgery, Tohoku University School of Medicine, Sendai, Miyagi 980-8575 (Japan); Horii, Akira, E-mail: horii@m.tains.tohoku.ac.jp [Department of Molecular Pathology, Tohoku University School of Medicine, Sendai, Miyagi 980-8575 (Japan)

    2009-12-25

    Ndc80 has been shown to play an important role in stable microtubule-kinetochore attachment, chromosome alignment, and spindle checkpoint activation in mitosis. It is composed of two heterodimers, CDCA1-KNTC2 and SPC24-SPC25. Overexpression of CDCA1 and KNTC2 is reported to be associated with poor prognosis in non-small cell lung cancers (NSCLC), and siRNA-mediated knockdown against CDCA1 or KNTC2 has been found to inhibit cell proliferation and induction of apoptosis in NSCLC, ovarian cancer, cervical cancer and glioma. Therefore, CDCA1 and KNTC2 can be considered good candidates for molecular target therapy as well as diagnosis in some cancers. However, the role of the Ndc80 complex in colorectal and gastric cancers (CRC and GC) still remains unclear. In the present study, we used qRT-PCR to evaluate the expression levels of CDCA1, KNTC2, SPC24 and SPC25 in CRC and GC and employed siRNA-mediated knockdown to examine cell proliferation and apoptosis. mRNA overexpression of these four genes was observed in CRCs and GCs when compared with the corresponding normal mucosae. Additionally, the expression levels of tumor/normal ratios of CDCA1, KNTC2, SPC24 and SPC25 correlated with each other in CRCs. MTT assays revealed that cell growths after the siRNA-mediated knockdown of either CDCA1 or KNTC2 were significantly suppressed, and flow cytometry analyses revealed significant increases of the subG1 fractions after knockdown against both genes. Our present results suggest that expressional control of component molecules of Ndc80 can be utilized for molecular target therapy of patients with CRC and GC.

  19. siRNA-mediated knockdown against CDCA1 and KNTC2, both frequently overexpressed in colorectal and gastric cancers, suppresses cell proliferation and induces apoptosis

    International Nuclear Information System (INIS)

    Kaneko, Naoyuki; Miura, Koh; Gu, Zhaodi; Karasawa, Hideaki; Ohnuma, Shinobu; Sasaki, Hiroyuki; Tsukamoto, Nobukazu; Yokoyama, Satoru; Yamamura, Akihiro; Nagase, Hiroki; Shibata, Chikashi; Sasaki, Iwao; Horii, Akira

    2009-01-01

    Ndc80 has been shown to play an important role in stable microtubule-kinetochore attachment, chromosome alignment, and spindle checkpoint activation in mitosis. It is composed of two heterodimers, CDCA1-KNTC2 and SPC24-SPC25. Overexpression of CDCA1 and KNTC2 is reported to be associated with poor prognosis in non-small cell lung cancers (NSCLC), and siRNA-mediated knockdown against CDCA1 or KNTC2 has been found to inhibit cell proliferation and induction of apoptosis in NSCLC, ovarian cancer, cervical cancer and glioma. Therefore, CDCA1 and KNTC2 can be considered good candidates for molecular target therapy as well as diagnosis in some cancers. However, the role of the Ndc80 complex in colorectal and gastric cancers (CRC and GC) still remains unclear. In the present study, we used qRT-PCR to evaluate the expression levels of CDCA1, KNTC2, SPC24 and SPC25 in CRC and GC and employed siRNA-mediated knockdown to examine cell proliferation and apoptosis. mRNA overexpression of these four genes was observed in CRCs and GCs when compared with the corresponding normal mucosae. Additionally, the expression levels of tumor/normal ratios of CDCA1, KNTC2, SPC24 and SPC25 correlated with each other in CRCs. MTT assays revealed that cell growths after the siRNA-mediated knockdown of either CDCA1 or KNTC2 were significantly suppressed, and flow cytometry analyses revealed significant increases of the subG1 fractions after knockdown against both genes. Our present results suggest that expressional control of component molecules of Ndc80 can be utilized for molecular target therapy of patients with CRC and GC.

  20. miR2Pathway: A Novel Analytical Method to Discover MicroRNA-mediated Dysregulated Pathways Involved in Hepatocellular Carcinoma.

    Science.gov (United States)

    Li, Chaoxing; Dinu, Valentin

    2018-03-22

    MicroRNAs (miRNAs) are small, non-coding RNAs involved in the regulation of gene expression at a post-transcriptional level. Recent studies have shown miRNAs as key regulators of a variety of biological processes, such as proliferation, differentiation, apoptosis, metabolism, etc. Aberrantly expressed miRNAs influence individual gene expression level, but rewired miRNA-mRNA connections can influence the activity of biological pathways. Here, we define rewired miRNA-mRNA connections as the differential (rewiring) effects on the activity of biological pathways between hepatocellular carcinoma (HCC) and normal phenotypes. Our work presented here uses a PageRank-based approach to measure the degree of miRNA-mediated dysregulation of biological pathways between HCC and normal samples based on rewired miRNA-mRNA connections. In our study, we regard the degree of miRNA-mediated dysregulation of biological pathways as disease risk of biological pathways. Therefore, we propose a new method, miR2Pathway, to measure and rank the degree of miRNA-mediated dysregulation of biological pathways by measuring the total differential influence of miRNAs on the activity of pathways between HCC and normal states. miR2Pathway proposed here systematically shows the first evidence for a mechanism of biological pathways being dysregulated by rewired miRNA-mRNA connections, and provides new insight into exploring mechanisms behind HCC. Thus, miR2Pathway is a novel method to identify and rank miRNA-dysregulated pathways in HCC. Copyright © 2018. Published by Elsevier Inc.

  1. Paramutation of tobacco transgenes by small RNA-mediated transcriptional gene silencing

    Czech Academy of Sciences Publication Activity Database

    Crhák Khaitová, Lucie; Fojtová, M.; Křížová, Kateřina; Lunerová Bedřichová, Jana; Fulneček, Jaroslav; Depicker, A.; Kovařík, Aleš

    2011-01-01

    Roč. 6, č. 5 (2011), s. 650-660 ISSN 1559-2294 R&D Projects: GA ČR(CZ) GD204/09/H002; GA MŠk(CZ) LC06004 Grant - others:GA ČR(CZ) GPP501/11/P667 Program:GP Institutional research plan: CEZ:AV0Z50040507; CEZ:AV0Z50040702 Keywords : transcriptional gene silencing * transgene epialleles * DNA methylation Subject RIV: BO - Biophysics Impact factor: 4.318, year: 2011

  2. Regulatory RNAs in Bacillus subtilis: a Gram-Positive Perspective on Bacterial RNA-Mediated Regulation of Gene Expression

    Science.gov (United States)

    Mars, Ruben A. T.; Nicolas, Pierre; Denham, Emma L.

    2016-01-01

    SUMMARY Bacteria can employ widely diverse RNA molecules to regulate their gene expression. Such molecules include trans-acting small regulatory RNAs, antisense RNAs, and a variety of transcriptional attenuation mechanisms in the 5′ untranslated region. Thus far, most regulatory RNA research has focused on Gram-negative bacteria, such as Escherichia coli and Salmonella. Hence, there is uncertainty about whether the resulting insights can be extrapolated directly to other bacteria, such as the Gram-positive soil bacterium Bacillus subtilis. A recent study identified 1,583 putative regulatory RNAs in B. subtilis, whose expression was assessed across 104 conditions. Here, we review the current understanding of RNA-based regulation in B. subtilis, and we categorize the newly identified putative regulatory RNAs on the basis of their conservation in other bacilli and the stability of their predicted secondary structures. Our present evaluation of the publicly available data indicates that RNA-mediated gene regulation in B. subtilis mostly involves elements at the 5′ ends of mRNA molecules. These can include 5′ secondary structure elements and metabolite-, tRNA-, or protein-binding sites. Importantly, sense-independent segments are identified as the most conserved and structured potential regulatory RNAs in B. subtilis. Altogether, the present survey provides many leads for the identification of new regulatory RNA functions in B. subtilis. PMID:27784798

  3. Spatio-temporal requirements for transposable element piRNA-mediated silencing during Drosophila oogenesis.

    Science.gov (United States)

    Dufourt, Jérémy; Dennis, Cynthia; Boivin, Antoine; Gueguen, Nathalie; Théron, Emmanuelle; Goriaux, Coline; Pouchin, Pierre; Ronsseray, Stéphane; Brasset, Emilie; Vaury, Chantal

    2014-02-01

    During Drosophila oogenesis, transposable element (TE) repression involves the Piwi-interacting RNA (piRNA) pathway which ensures genome integrity for the next generation. We developed a transgenic model to study repression of the Idefix retrotransposon in the germline. Using a candidate gene KD-approach, we identified differences in the spatio-temporal requirements of the piRNA pathway components for piRNA-mediated silencing. Some of them (Aub, Vasa, Spn-E) are necessary in very early stages of oogenesis within the germarium and appear to be less important for efficient TE silencing thereafter. Others (Piwi, Ago3, Mael) are required at all stages of oogenesis. Moreover, during early oogenesis, in the dividing cysts within the germarium, Idefix anti-sense transgenes escape host control, and this is associated with very low piwi expression. Silencing of P-element-based transgenes is also strongly weakened in these cysts. This region, termed the 'Piwiless pocket' or Pilp, may ensure that new TE insertions occur and are transmitted to the next generation, thereby contributing to genome dynamics. In contrast, piRNA-mediated silencing is strong in germline stem cells in which TE mobilization is tightly repressed ensuring the continued production of viable germline cysts.

  4. A brain-targeting lipidated peptide for neutralizing RNA-mediated toxicity in Polyglutamine Diseases

    DEFF Research Database (Denmark)

    Zhang, Qian; Yang, Mengbi; Sørensen, Kasper K.

    2017-01-01

    Polyglutamine (PolyQ) diseases are progressive neurodegenerative disorders caused by both protein- and RNA-mediated toxicities. We previously showed that a peptidyl inhibitor, P3, which binds directly to expanded CAG RNA can inhibit RNA-induced nucleolar stress and suppress RNA-induced neurotoxic......Polyglutamine (PolyQ) diseases are progressive neurodegenerative disorders caused by both protein- and RNA-mediated toxicities. We previously showed that a peptidyl inhibitor, P3, which binds directly to expanded CAG RNA can inhibit RNA-induced nucleolar stress and suppress RNA...... with no observed toxic effects. Further N-palmitoylation of P3V8 (L1P3V8) not only significantly improved its cellular uptake and stability, but also facilitated its systemic exposure and brain uptake in rats via intranasal administration. Our findings demonstrate that concomitant N-acetylation, C......-amidation and palmitoylation of P3 significantly improve both its bioactivity and pharmacological profile. L1P3V8 possesses drug/lead-like properties that can be further developed into a lead inhibitor for the treatment of polyQ diseases....

  5. LIM-domain proteins, LIMD1, Ajuba, and WTIP are required for microRNA-mediated gene silencing.

    Science.gov (United States)

    James, Victoria; Zhang, Yining; Foxler, Daniel E; de Moor, Cornelia H; Kong, Yi Wen; Webb, Thomas M; Self, Tim J; Feng, Yungfeng; Lagos, Dimitrios; Chu, Chia-Ying; Rana, Tariq M; Morley, Simon J; Longmore, Gregory D; Bushell, Martin; Sharp, Tyson V

    2010-07-13

    In recent years there have been major advances with respect to the identification of the protein components and mechanisms of microRNA (miRNA) mediated silencing. However, the complete and precise repertoire of components and mechanism(s) of action remain to be fully elucidated. Herein we reveal the identification of a family of three LIM domain-containing proteins, LIMD1, Ajuba and WTIP (Ajuba LIM proteins) as novel mammalian processing body (P-body) components, which highlight a novel mechanism of miRNA-mediated gene silencing. Furthermore, we reveal that LIMD1, Ajuba, and WTIP bind to Ago1/2, RCK, Dcp2, and eIF4E in vivo, that they are required for miRNA-mediated, but not siRNA-mediated gene silencing and that all three proteins bind to the mRNA 5' m(7)GTP cap-protein complex. Mechanistically, we propose the Ajuba LIM proteins interact with the m(7)GTP cap structure via a specific interaction with eIF4E that prevents 4EBP1 and eIF4G interaction. In addition, these LIM-domain proteins facilitate miRNA-mediated gene silencing by acting as an essential molecular link between the translationally inhibited eIF4E-m(7)GTP-5(')cap and Ago1/2 within the miRISC complex attached to the 3'-UTR of mRNA, creating an inhibitory closed-loop complex.

  6. The role of incoherent microRNA-mediated feedforward loops in noise buffering.

    Directory of Open Access Journals (Sweden)

    Matteo Osella

    2011-03-01

    Full Text Available MicroRNAs are endogenous non-coding RNAs which negatively regulate the expression of protein-coding genes in plants and animals. They are known to play an important role in several biological processes and, together with transcription factors, form a complex and highly interconnected regulatory network. Looking at the structure of this network, it is possible to recognize a few overrepresented motifs which are expected to perform important elementary regulatory functions. Among them, a special role is played by the microRNA-mediated feedforward loop in which a master transcription factor regulates a microRNA and, together with it, a set of target genes. In this paper we show analytically and through simulations that the incoherent version of this motif can couple the fine-tuning of a target protein level with an efficient noise control, thus conferring precision and stability to the overall gene expression program, especially in the presence of fluctuations in upstream regulators. Among the other results, a nontrivial prediction of our model is that the optimal attenuation of fluctuations coincides with a modest repression of the target expression. This feature is coherent with the expected fine-tuning function and in agreement with experimental observations of the actual impact of a wide class of microRNAs on the protein output of their targets. Finally, we describe the impact on noise-buffering efficiency of the cross-talk between microRNA targets that can naturally arise if the microRNA-mediated circuit is not considered as isolated, but embedded in a larger network of regulations.

  7. mRNA isoform diversity can obscure detection of miRNA-mediated control of translation

    Science.gov (United States)

    Clancy, Jennifer L.; Wei, Grace H.; Echner, Nicole; Humphreys, David T.; Beilharz, Traude H.; Preiss, Thomas

    2011-01-01

    Reporter-based studies support inhibition of translation at the level of initiation as a substantial component of the miRNA mechanism, yet recent global analyses have suggested that they predominantly act through decreasing target mRNA stability. Cells commonly coexpress several processing isoforms of an mRNA, which may also differ in their regulatory untranslated regions (UTR). In particular, cancer cells are known to express high levels of short 3′ UTR isoforms that evade miRNA-mediated regulation, whereas longer 3′ UTRs predominate in nontransformed cells. To test whether mRNA isoform diversity can obscure detection of miRNA-mediated control at the level of translation, we assayed the responses of 11 endogenous let-7 targets to inactivation of this miRNA in HeLa cells, an intensively studied model system. We show that translational regulation in many cases appears to be modest when measuring the composite polysome profile of all extant isoforms of a given mRNA by density ultracentrifugation. In contrast, we saw clear effects at the level of translation initiation for multiple examples when selectively profiling mRNA isoforms carrying the 5′ or 3′ untranslated regions that were actually permissive to let-7 action, or when let-7 and a second targeting miRNA were jointly manipulated. Altogether, these results highlight a caveat to the mechanistic interpretation of data from global miRNA target analyses in transformed cells. Importantly, they reaffirm the importance of translational control as part of the miRNA mechanism in animal cells. PMID:21467217

  8. microRNA-mediated messenger RNA deadenylation contributes to translational repression in mammalian cells.

    Directory of Open Access Journals (Sweden)

    Traude H Beilharz

    2009-08-01

    Full Text Available Animal microRNAs (miRNAs typically regulate gene expression by binding to partially complementary target sites in the 3' untranslated region (UTR of messenger RNA (mRNA reducing its translation and stability. They also commonly induce shortening of the mRNA 3' poly(A tail, which contributes to their mRNA decay promoting function. The relationship between miRNA-mediated deadenylation and translational repression has been less clear. Using transfection of reporter constructs carrying three imperfectly matching let-7 target sites in the 3' UTR into mammalian cells we observe rapid target mRNA deadenylation that precedes measureable translational repression by endogenous let-7 miRNA. Depleting cells of the argonaute co-factors RCK or TNRC6A can impair let-7-mediated repression despite ongoing mRNA deadenylation, indicating that deadenylation alone is not sufficient to effect full repression. Nevertheless, the magnitude of translational repression by let-7 is diminished when the target reporter lacks a poly(A tail. Employing an antisense strategy to block deadenylation of target mRNA with poly(A tail also partially impairs translational repression. On the one hand, these experiments confirm that tail removal by deadenylation is not strictly required for translational repression. On the other hand they show directly that deadenylation can augment miRNA-mediated translational repression in mammalian cells beyond stimulating mRNA decay. Taken together with published work, these results suggest a dual role of deadenylation in miRNA function: it contributes to translational repression as well as mRNA decay and is thus critically involved in establishing the quantitatively appropriate physiological response to miRNAs.

  9. miRNA-mediated functional changes through co-regulating function related genes.

    Directory of Open Access Journals (Sweden)

    Jie He

    Full Text Available BACKGROUND: MicroRNAs play important roles in various biological processes involving fairly complex mechanism. Analysis of genome-wide miRNA microarray demonstrate that a single miRNA can regulate hundreds of genes, but the regulative extent on most individual genes is surprisingly mild so that it is difficult to understand how a miRNA provokes detectable functional changes with such mild regulation. RESULTS: To explore the internal mechanism of miRNA-mediated regulation, we re-analyzed the data collected from genome-wide miRNA microarray with bioinformatics assay, and found that the transfection of miR-181b and miR-34a in Hela and HCT-116 tumor cells regulated large numbers of genes, among which, the genes related to cell growth and cell death demonstrated high Enrichment scores, suggesting that these miRNAs may be important in cell growth and cell death. MiR-181b induced changes in protein expression of most genes that were seemingly related to enhancing cell growth and decreasing cell death, while miR-34a mediated contrary changes of gene expression. Cell growth assays further confirmed this finding. In further study on miR-20b-mediated osteogenesis in hMSCs, miR-20b was found to enhance osteogenesis by activating BMPs/Runx2 signaling pathway in several stages by co-repressing of PPARγ, Bambi and Crim1. CONCLUSIONS: With its multi-target characteristics, miR-181b, miR-34a and miR-20b provoked detectable functional changes by co-regulating functionally-related gene groups or several genes in the same signaling pathway, and thus mild regulation from individual miRNA targeting genes could have contributed to an additive effect. This might also be one of the modes of miRNA-mediated gene regulation.

  10. Removing interfering contaminations from gelatin lifters.

    Science.gov (United States)

    Shor, Yaron; Tsach, Tsadok; Wiesner, Sarena; Meir, Gur

    2005-11-01

    Gelatin lifter is widely used for recovering shoeprints from crime scenes. Dusty shoeprints removed from paper with loose fibers, cloth or plasterboard, might be concealed by the detached fibers. A novel technique to clean the gelatin lifter from the interfering contaminations, using adhesive lifters, was developed. The adhesive lifter is applied directly on the surface of the gelatin lifter, and is removed instantly. The adhesive lifter removes the upper layer of the attached material on the gelatin lifter. After removing the concealing material from the hidden imprint, the quality of the visualized imprint is improved. The cleaning process can be applied as many times as needed and the optimum number is different for each substrate. The small dust particles comprising the shoeprint remained attached to the sticky side of the gelatin lifter even though the adhesion force applied by the adhesive lifter is great. Repeating the procedure too many times could harm the quality of the print severely, yet the advantages of this method are greater than the risks of relocation of image quality reduction.

  11. Construction of miRNA-miRNA networks revealing the complexity of miRNA-mediated mechanisms in trastuzumab treated breast cancer cell lines

    Science.gov (United States)

    Cilek, Emine Ezel; Ozturk, Hakime

    2017-01-01

    Trastuzumab is a monoclonal antibody frequently used to prevent the progression of HER2+ breast cancers, which constitute approximately 20% of invasive breast cancers. microRNAs (miRNAs) are small, non-coding RNA molecules that are known to be involved in gene regulation. With their emerging roles in cancer, they are recently promoted as potential candidates to mediate therapeutic actions by targeting genes associated with drug response. In this study we explored miRNA-mediated regulation of trastuzumab mechanisms by identifying the important miRNAs responsible for the drug response via homogenous network analysis. Our network model enabled us to simplify the complexity of miRNA interactions by connecting them through their common pathways. We outlined the functionally relevant miRNAs by constructing pathway-based miRNA-miRNA networks in SKBR3 and BT474 cells, respectively. Identification of the most targeted genes revealed that trastuzumab responsive miRNAs favourably regulate the repression of targets with longer 3’UTR than average considered to be key elements, while the miRNA-miRNA networks highlighted central miRNAs such as hsa-miR-3976 and hsa-miR-3671 that showed strong interactions with the remaining members of the network. Furthermore, the clusters of the miRNA-miRNA networks showed that trastuzumab response was mostly established through cancer related and metabolic pathways. hsa-miR-216b was found to be the part of the most powerful interactions of metabolic pathways, which was defined in the largest clusters in both cell lines. The network based representation of miRNA-miRNA interactions through their shared pathways provided a better understanding of miRNA-mediated drug response and could be suggested for further characterization of miRNA functions. PMID:28981542

  12. Construction of miRNA-miRNA networks revealing the complexity of miRNA-mediated mechanisms in trastuzumab treated breast cancer cell lines.

    Directory of Open Access Journals (Sweden)

    Emine Ezel Cilek

    Full Text Available Trastuzumab is a monoclonal antibody frequently used to prevent the progression of HER2+ breast cancers, which constitute approximately 20% of invasive breast cancers. microRNAs (miRNAs are small, non-coding RNA molecules that are known to be involved in gene regulation. With their emerging roles in cancer, they are recently promoted as potential candidates to mediate therapeutic actions by targeting genes associated with drug response. In this study we explored miRNA-mediated regulation of trastuzumab mechanisms by identifying the important miRNAs responsible for the drug response via homogenous network analysis. Our network model enabled us to simplify the complexity of miRNA interactions by connecting them through their common pathways. We outlined the functionally relevant miRNAs by constructing pathway-based miRNA-miRNA networks in SKBR3 and BT474 cells, respectively. Identification of the most targeted genes revealed that trastuzumab responsive miRNAs favourably regulate the repression of targets with longer 3'UTR than average considered to be key elements, while the miRNA-miRNA networks highlighted central miRNAs such as hsa-miR-3976 and hsa-miR-3671 that showed strong interactions with the remaining members of the network. Furthermore, the clusters of the miRNA-miRNA networks showed that trastuzumab response was mostly established through cancer related and metabolic pathways. hsa-miR-216b was found to be the part of the most powerful interactions of metabolic pathways, which was defined in the largest clusters in both cell lines. The network based representation of miRNA-miRNA interactions through their shared pathways provided a better understanding of miRNA-mediated drug response and could be suggested for further characterization of miRNA functions.

  13. Evidence for miRNA-mediated modulation of the host transcriptome in cnidarian-dinoflagellate symbiosis

    KAUST Repository

    Baumgarten, Sebastian

    2017-12-08

    Reef-building corals and other cnidarians living in symbiotic relationships with intracellular, photosynthetic dinoflagellates in the genus Symbiodinium undergo transcriptomic changes during infection with the algae and maintenance of the endosymbiont population. However, the precise regulatory mechanisms modulating the host transcriptome are unknown. Here we report apparent post-transcriptional gene regulation by miRNAs in the sea anemone Aiptasia, a model system for cnidarian-dinoflagellate endosymbiosis. Aiptasia encodes mainly species-specific miRNAs, and there appears to have been recent differentiation within the Aiptasia genome of miRNAs that are commonly conserved among anthozoan cnidarians. Analysis of miRNA expression showed that both conserved and species-specific miRNAs are differentially expressed in response to endosymbiont infection. Using cross-linking immunoprecipitation of Argonaute, the central protein of the miRNA-induced silencing complex, we identified miRNA binding sites on a transcriptome-wide scale and found that the targets of the miRNAs regulated in response to symbiosis include genes previously implicated in biological processes related to Symbiodinium infection. Our study shows that cnidarian miRNAs recognize their mRNA targets via high-complementarity target binding and suggests that miRNA-mediated modulations of genes and pathways are important during the onset and maintenance of cnidarian-dinoflagellate endosymbiosis. This article is protected by copyright. All rights reserved.

  14. miRNA-mediated auxin signalling repression during Vat-mediated aphid resistance in Cucumis melo.

    Science.gov (United States)

    Sattar, Sampurna; Addo-Quaye, Charles; Thompson, Gary A

    2016-06-01

    Resistance to Aphis gossypii in melon is attributed to the presence of the single dominant R gene virus aphid transmission (Vat), which is biologically expressed as antibiosis, antixenosis and tolerance. However, the mechanism of resistance is poorly understood at the molecular level. Aphid-induced transcriptional changes, including differentially expressed miRNA profiles that correspond to resistance interaction have been reported in melon. The potential regulatory roles of miRNAs in Vat-mediated aphid resistance were further revealed by identifying the specific miRNA degradation targets. A total of 70 miRNA:target pairs, including 28 novel miRNA:target pairs, for the differentially expressed miRNAs were identified: 11 were associated with phytohormone regulation, including six miRNAs that potentially regulate auxin interactions. A model for a redundant regulatory system of miRNA-mediated auxin insensitivity is proposed that incorporates auxin perception, auxin modification and auxin-regulated transcription. Chemically inhibiting the transport inhibitor response-1 (TIR-1) auxin receptor in susceptible melon tissues provides in vivo support for the model of auxin-mediated impacts on A. gossypii resistance. © 2016 John Wiley & Sons Ltd.

  15. Gold nanoparticle mediated laser transfection for efficient siRNA mediated gene knock down.

    Directory of Open Access Journals (Sweden)

    Dag Heinemann

    Full Text Available Laser based transfection methods have proven to be an efficient and gentle alternative to established molecule delivery methods like lipofection or electroporation. Among the laser based methods, gold nanoparticle mediated laser transfection bears the major advantage of high throughput and easy usability. This approach uses plasmon resonances on gold nanoparticles unspecifically attached to the cell membrane to evoke transient and spatially defined cell membrane permeabilization. In this study, we explore the parameter regime for gold nanoparticle mediated laser transfection for the delivery of molecules into cell lines and prove its suitability for siRNA mediated gene knock down. The developed setup allows easy usage and safe laser operation in a normal lab environment. We applied a 532 nm Nd:YAG microchip laser emitting 850 ps pulses at a repetition rate of 20.25 kHz. Scanning velocities of the laser spot over the sample of up to 200 mm/s were tested without a decline in perforation efficiency. This velocity leads to a process speed of ∼8 s per well of a 96 well plate. The optimal particle density was determined to be ∼6 particles per cell using environmental scanning electron microscopy. Applying the optimized parameters transfection efficiencies of 88% were achieved in canine pleomorphic adenoma ZMTH3 cells using a fluorescent labeled siRNA while maintaining a high cell viability of >90%. Gene knock down of d2-EGFP was demonstrated and validated by fluorescence repression and western blot analysis. On basis of our findings and established mathematical models we suppose a mixed transfection mechanism consisting of thermal and multiphoton near field effects. Our findings emphasize that gold nanoparticle mediated laser transfection provides an excellent tool for molecular delivery for both, high throughput purposes and the transfection of sensitive cells types.

  16. Gold Nanoparticle Mediated Laser Transfection for Efficient siRNA Mediated Gene Knock Down

    Science.gov (United States)

    Heinemann, Dag; Schomaker, Markus; Kalies, Stefan; Schieck, Maximilian; Carlson, Regina; Escobar, Hugo Murua; Ripken, Tammo; Meyer, Heiko; Heisterkamp, Alexander

    2013-01-01

    Laser based transfection methods have proven to be an efficient and gentle alternative to established molecule delivery methods like lipofection or electroporation. Among the laser based methods, gold nanoparticle mediated laser transfection bears the major advantage of high throughput and easy usability. This approach uses plasmon resonances on gold nanoparticles unspecifically attached to the cell membrane to evoke transient and spatially defined cell membrane permeabilization. In this study, we explore the parameter regime for gold nanoparticle mediated laser transfection for the delivery of molecules into cell lines and prove its suitability for siRNA mediated gene knock down. The developed setup allows easy usage and safe laser operation in a normal lab environment. We applied a 532 nm Nd:YAG microchip laser emitting 850 ps pulses at a repetition rate of 20.25 kHz. Scanning velocities of the laser spot over the sample of up to 200 mm/s were tested without a decline in perforation efficiency. This velocity leads to a process speed of ∼8 s per well of a 96 well plate. The optimal particle density was determined to be ∼6 particles per cell using environmental scanning electron microscopy. Applying the optimized parameters transfection efficiencies of 88% were achieved in canine pleomorphic adenoma ZMTH3 cells using a fluorescent labeled siRNA while maintaining a high cell viability of >90%. Gene knock down of d2-EGFP was demonstrated and validated by fluorescence repression and western blot analysis. On basis of our findings and established mathematical models we suppose a mixed transfection mechanism consisting of thermal and multiphoton near field effects. Our findings emphasize that gold nanoparticle mediated laser transfection provides an excellent tool for molecular delivery for both, high throughput purposes and the transfection of sensitive cells types. PMID:23536802

  17. siRNA-mediated c-Rel knockdown ameliorates collagen-induced arthritis in mice.

    Science.gov (United States)

    Fan, Tingting; Zhong, Fuhua; Liu, Ruiling; Chen, Youhai H; Wang, Ting; Ruan, Qingguo

    2018-03-01

    Previous studies have shown that inflammatory mediators involved in the development of rheumatoid arthritis (RA) are regulated by the Rel/nuclear factor-κB (Rel/NF-κB) transcription factor family. c-Rel, a member of the Rel/NF-κB family that is preferentially expressed by immune cells, is a risk factor for several inflammatory diseases including RA. In the current study, we investigated whether targeting c-Rel can be used to treat collagen-induced arthritis, an animal model for RA. c-Rel specific siRNA (siRel) delivered by nanoparticles was used to knockdown the expression of c-Rel. Our results showed that siRel treatment significantly ameliorated collagen-induced arthritis. Further study revealed that c-Rel expression in the dendritic cells and macrophages from mice treated with siRel was significantly down-regulated. Consistent with the phenotypical result, the expression of inflammatory cytokines TNF-α, IL-1β, IL-6, IL-12 and IL-23 by peritoneal macrophages and splenocytes were significantly decreased. In addition, attenuated systemic and collagen-specific Th1 and Th17 immune responses were observed. Furthermore, we found that the expression of inflammatory cytokines was significantly down-regulated and the infiltration of CD3 + T cells and F4/80 + macrophages was markedly reduced in hind paws of mice treated with siRel. Collectively, our study provides strong evidence that siRNA-mediated c-Rel knockdown can suppress the development of collagen-induced arthritis in mice. Therefore, blocking c-Rel may represent an attracting strategy for the treatment of human rheumatoid arthritis. Copyright © 2018 Elsevier B.V. All rights reserved.

  18. Identification of microRNAs and their target genes explores miRNA-mediated regulatory network of cytoplasmic male sterility occurrence during anther development in radish (Raphanus sativus L.

    Directory of Open Access Journals (Sweden)

    Wei Zhang

    2016-07-01

    Full Text Available MicroRNAs (miRNAs are a type of endogenous non-coding small RNAs that play critical roles in plant growth and developmental processes. Cytoplasmic male sterility (CMS is typically a maternally inherited trait and widely used in plant heterosis utilization. However, the miRNA-mediated regulatory network of CMS occurrence during anther development remains largely unknown in radish. In this study, a comparative small RNAome sequencing was conducted in floral buds of CMS line ‘WA’ and its maintainer line ‘WB’ by high-throughput sequencing. A total of 162 known miRNAs belonging to 25 conserved and 24 non-conserved miRNA families were isolated and 27 potential novel miRNA families were identified for the first time in floral buds of radish. Of these miRNAs, 28 known and 14 potential novel miRNAs were differentially expressed during anther development. Several target genes for CMS occurrence-related miRNAs encoding important transcription factors and functional proteins, which might be involved in multiple biological processes including auxin signaling pathways, signal transduction, miRNA target silencing, floral organ development and organellar gene expression. Moreover, the expression patterns of several CMS occurrence-related miRNAs and their targets during three stages of anther development were validated by qRT-PCR. In addition, a potential miRNA-mediated regulatory network of CMS occurrence during anther development was firstly proposed in radish. These findings contribute new insights into complex miRNA-mediated genetic regulatory network of CMS occurrence and advance our understanding of the roles of miRNAs during CMS occurrence and microspore formation in radish and other crops.

  19. microRNA-mediated resistance to hypoglycemia in the HepG2 human hepatoma cell line

    International Nuclear Information System (INIS)

    Ueki, Satomi; Murakami, Yuko; Yamada, Shoji; Kimura, Masaki; Saito, Yoshimasa; Saito, Hidetsugu

    2016-01-01

    It is generally accepted that the energy resources of cancer cells rely on anaerobic metabolism or the glycolytic system, even if they have sufficient oxygen. This is known as the Warburg effect. The cells skillfully survive under hypoglycemic conditions when their circumstances change, which probably at least partly involves microRNA (miRNA)-mediated regulation. To determine how cancer cells exploit miRNA-mediated epigenetic mechanisms to survive in hypoglycemic conditions, we used DNA microarray analysis to comprehensively and simultaneously compare the expression of miRNAs and mRNAs in the HepG2 human hepatoma cell line and in cultured normal human hepatocytes. The hypoglycemic condition decreased the expression of miRNA-17-5p and -20a-5p in hepatoma cells and consequently upregulated the expression of their target gene p21. These regulations were also confirmed by using antisense inhibitors of these miRNAs. In addition to this change, the hypoglycemic condition led to upregulated expression of heat shock proteins and increased resistance to caspase-3-induced apoptosis. However, we could not identify miRNA-mediated regulations, despite using comprehensive detection. Several interesting genes were also found to be upregulated in the hypoglycemic condition by the microarray analysis, probably because of responding to this cellular stress. These results suggest that cancer cells skillfully survive in hypoglycemic conditions, which frequently occur in malignancies, and that some of the gene regulation of this process is manipulated by miRNAs. The online version of this article (doi:10.1186/s12885-016-2762-7) contains supplementary material, which is available to authorized users

  20. Bombyx mori histone methyltransferase BmAsh2 is essential for silkworm piRNA-mediated sex determination.

    Science.gov (United States)

    Li, Zhiqian; You, Lang; Yan, Dong; James, Anthony A; Huang, Yongping; Tan, Anjiang

    2018-02-01

    Sex determination is a hierarchically-regulated process with high diversity in different organisms including insects. The W chromosome-derived Fem piRNA has been identified as the primary sex determination factor in the lepidopteran insect, Bombyx mori, revealing a distinctive piRNA-mediated sex determination pathway. However, the comprehensive mechanism of silkworm sex determination is still poorly understood. We show here that the silkworm PIWI protein BmSiwi, but not BmAgo3, is essential for silkworm sex determination. CRISPR/Cas9-mediated depletion of BmSiwi results in developmental arrest in oogenesis and partial female sexual reversal, while BmAgo3 depletion only affects oogenesis. We identify three histone methyltransferases (HMTs) that are significantly down-regulated in BmSiwi mutant moths. Disruption one of these, BmAsh2, causes dysregulation of piRNAs and transposable elements (TEs), supporting a role for it in the piRNA signaling pathway. More importantly, we find that BmAsh2 mutagenesis results in oogenesis arrest and partial female-to-male sexual reversal as well as dysregulation of the sex determination genes, Bmdsx and BmMasc. Mutagenesis of other two HMTs, BmSETD2 and BmEggless, does not affect piRNA-mediated sex determination. Histological analysis and immunoprecipitation results support a functional interaction between the BmAsh2 and BmSiwi proteins. Our data provide the first evidence that the HMT, BmAsh2, plays key roles in silkworm piRNA-mediated sex determination.

  1. miRNA-mediated post-transcriptional silencing of transgenes leads to increased adeno-associated viral vector yield and targeting specificity.

    Science.gov (United States)

    Reid, C A; Boye, S L; Hauswirth, W W; Lipinski, D M

    2017-08-01

    The production of high-titer recombinant adeno-associated virus (rAAV) vector is essential for treatment of genetic diseases affecting the retina and choroid, where anatomical constraints may limit injectable volumes. Problematically, cytotoxicity arising from overexpression of the transgene during vector production frequently leads to a reduction in vector yield. Herein, we evaluate the use of microRNA (miRNA)-mediated silencing to limit overexpression of cytotoxic transgenes during packaging as a method of increasing vector yield. We examined if post-transcriptional regulation of transgenes during packaging via miRNA technology would lead to increased rAAV yields. Our results demonstrate that silencing of cytotoxic transgenes during production resulted in up to a 22-fold increase in vector yield. The inclusion of organ-specific miRNA sequences improved biosafety by limiting off-target expression following systemic rAAV administration. The small size (22-23 bp) of the target site allows for the inclusion of multiple copies into the vector with minimal impact on coding capacity. Taken together, our results suggest that inclusion of miRNA target sites into the 3'-untranslated region of the AAV cassette allow for silencing of cytotoxic transgenes during vector production leading to improved vector yield, in addition to increasing targeting specificity without reliance on cell-specific promoters.

  2. Gene Expression Profile Changes After Short-activating RNA-mediated Induction of Endogenous Pluripotency Factors in Human Mesenchymal Stem Cells

    Directory of Open Access Journals (Sweden)

    Jon Voutila

    2012-01-01

    Full Text Available It is now recognized that small noncoding RNA sequences have the ability to mediate transcriptional activation of specific target genes in human cells. Using bioinformatics analysis and functional screening, we screened short-activating RNA (saRNA oligonucleotides designed to target the promoter regions of the pluripotency reprogramming factors, Kruppel-like factor 4 (KLF4 and c-MYC. We identified KLF4 and c-MYC promoter-targeted saRNA sequences that consistently induced increases in their respective levels of nascent mRNA and protein expression in a time- and dose-dependent manner, as compared with scrambled sequence control oligonucleotides. The functional consequences of saRNA-induced activation of each targeted reprogramming factor were then characterized by comprehensively profiling changes in gene expression by microarray analysis, which revealed significant increases in mRNA levels of their respective downstream pathway genes. Notably, the microarray profile after saRNA-mediated induction of endogenous KLF4 and c-MYC showed similar gene expression patterns for stem cell- and cell cycle-related genes as compared with lentiviral vector-mediated overexpression of exogenous KLF4 and c-MYC transgenes, while divergent gene expression patterns common to viral vector-mediated transgene delivery were also noted. The use of promoter-targeted saRNAs for the activation of pluripotency reprogramming factors could have broad implications for stem cell research.

  3. Paramecium tetraurelia chromatin assembly factor-1-like protein PtCAF-1 is involved in RNA-mediated control of DNA elimination.

    Science.gov (United States)

    Ignarski, Michael; Singh, Aditi; Swart, Estienne C; Arambasic, Miroslav; Sandoval, Pamela Y; Nowacki, Mariusz

    2014-10-29

    Genome-wide DNA remodelling in the ciliate Paramecium is ensured by RNA-mediated trans-nuclear crosstalk between the germline and the somatic genomes during sexual development. The rearrangements include elimination of transposable elements, minisatellites and tens of thousands non-coding elements called internally eliminated sequences (IESs). The trans-nuclear genome comparison process employs a distinct class of germline small RNAs (scnRNAs) that are compared against the parental somatic genome to select the germline-specific subset of scnRNAs that subsequently target DNA elimination in the progeny genome. Only a handful of proteins involved in this process have been identified so far and the mechanism of DNA targeting is unknown. Here we describe chromatin assembly factor-1-like protein (PtCAF-1), which we show is required for the survival of sexual progeny and localizes first in the parental and later in the newly developing macronucleus. Gene silencing shows that PtCAF-1 is required for the elimination of transposable elements and a subset of IESs. PTCAF-1 depletion also impairs the selection of germline-specific scnRNAs during development. We identify specific histone modifications appearing during Paramecium development which are strongly reduced in PTCAF-1 depleted cells. Our results demonstrate the importance of PtCAF-1 for the epigenetic trans-nuclear cross-talk mechanism. © The Author(s) 2014. Published by Oxford University Press on behalf of Nucleic Acids Research.

  4. siRNA-mediated Erc gene silencing suppresses tumor growth in Tsc2 mutant renal carcinoma model.

    Science.gov (United States)

    Imamura, Osamu; Okada, Hiroaki; Takashima, Yuuki; Zhang, Danqing; Kobayashi, Toshiyuki; Hino, Okio

    2008-09-18

    Silencing of gene expression by small interfering RNAs (siRNAs) is rapidly becoming a powerful tool for genetic analysis and represents a potential strategy for therapeutic product development. However, there are no reports of systemic delivery of siRNAs for stable treatment except short hairpin RNAs (shRNAs). On the other hand, there are many reports of systemic delivery of siRNAs for transient treatment using liposome carriers and others. With regard to shRNAs, a report showed fatality in mice due to oversaturation of cellular microRNA/short hairpin RNA pathways. Therefore, we decided to use original siRNA microspheres instead of shRNA for stable treatment of disease. In this study, we designed rat-specific siRNA sequences for Erc/mesothelin, which is a tumor-specific gene expressed in the Eker (Tsc2 mutant) rat model of hereditary renal cancer and confirmed the efficacy of gene silencing in vitro. Then, by using siRNA microspheres, we found that the suppression of Erc/mesothelin caused growth inhibition of Tsc2 mutant renal carcinoma cells in tumor implantation experiments in mice.

  5. associated virus (AAV)-mediated expression of small interfering RNA

    African Journals Online (AJOL)

    user

    2011-04-11

    Apr 11, 2011 ... expressed from a DNA-based vector by the function of. *Corresponding .... cleotides were designed, which contained a sense strand of p53 or ..... Subthalamic GAD gene transfer in Parkinson disease patients who are candidates for deep brain stimulation. Hum. Gene Ther. 12(12): 1589-1591. Dufourny L ...

  6. Control over interfering memories in eating disorders.

    Science.gov (United States)

    Stramaccia, Davide Francesco; Penolazzi, Barbara; Libardi, Arianna; Genovese, Aldo; Castelli, Luigi; Palomba, Daniela; Galfano, Giovanni

    2018-02-01

    Recent studies have suggested that patients suffering from either anorexia nervosa (AN) or bulimia nervosa (BN) exhibit abnormal performance in the ability to control cognitive interference in response selection. We assessed the status of cognitive control in episodic memory by addressing the ability to inhibit interfering memories. To this end, we used the retrieval-practice paradigm, which allows for measuring both the beneficial and the detrimental effects of memory practice. The latter phenomenon, known as retrieval-induced forgetting (RIF), is thought to reflect an adaptive inhibitory mechanism aimed at reducing competition in memory retrieval. Twenty-seven healthy controls and 27 patients suffering from eating disorders (either AN or BN) performed a retrieval-practice paradigm and a control task addressing general reactivity and filled a self-report questionnaire on impulsivity. No differences between patients and healthy controls were observed for the beneficial effects of practice. The same pattern also emerged for RIF. However, when patients with AN and BN were analyzed separately, a clear dissociation emerged: patients with AN displayed no hint of RIF, whereas patients with BN showed an intact memory suppression performance. No group differences emerged in the control task. Our findings suggest a specific impairment in the ability to suppress interfering memories in patients with AN, thus extending current evidence of cognitive control deficits in AN to episodic memory.

  7. Short-hairpin RNA-mediated stable silencing of Grb2 impairs cell growth and DNA synthesis

    International Nuclear Information System (INIS)

    Di Fulvio, Mauricio; Henkels, Karen M.; Gomez-Cambronero, Julian

    2007-01-01

    Grb2 is an SH2-SH3 protein adaptor responsible for linking growth factor receptors with intracellular signaling cascades. To study the role of Grb2 in cell growth, we have generated a new COS7 cell line (COS7 shGrb2 ), based on RNAi technology, as null mutations in mammalian Grb2 genes are lethal in early development. This novel cell line continuously expresses a short hairpin RNA that targets endogenous Grb2. Stable COS7 shGrb2 cells had the shGrb2 integrated into the genomic DNA and carried on SiL construct (made refractory to the shRNA-mediated interference), but not with an SH2-deficient mutant (R86K). Thus, a viable knock-down and rescue protocol has demonstrated that Grb2 is crucial for cell proliferation

  8. siRNA-Mediated Silencing of doublesex during Female Development of the Dengue Vector Mosquito Aedes aegypti.

    Directory of Open Access Journals (Sweden)

    Keshava Mysore

    2015-11-01

    Full Text Available The development of sex-specific traits, including the female-specific ability to bite humans and vector disease, is critical for vector mosquito reproduction and pathogen transmission. Doublesex (Dsx, a terminal transcription factor in the sex determination pathway, is known to regulate sex-specific gene expression during development of the dengue fever vector mosquito Aedes aegypti. Here, the effects of developmental siRNA-mediated dsx silencing were assessed in adult females. Targeting of dsx during A. aegypti development resulted in decreased female wing size, a correlate for body size, which is typically larger in females. siRNA-mediated targeting of dsx also resulted in decreased length of the adult female proboscis. Although dsx silencing did not impact female membrane blood feeding or mating behavior in the laboratory, decreased fecundity and fertility correlated with decreased ovary length, ovariole length, and ovariole number in dsx knockdown females. Dsx silencing also resulted in disruption of olfactory system development, as evidenced by reduced length of the female antenna and maxillary palp and the sensilla present on these structures, as well as disrupted odorant receptor expression. Female lifespan, a critical component of the ability of A. aegypti to transmit pathogens, was also significantly reduced in adult females following developmental targeting of dsx. The results of this investigation demonstrate that silencing of dsx during A. aegypti development disrupts multiple sex-specific morphological, physiological, and behavioral traits of adult females, a number of which are directly or indirectly linked to mosquito reproduction and pathogen transmission. Moreover, the olfactory phenotypes observed connect Dsx to development of the olfactory system, suggesting that A. aegypti will be an excellent system in which to further assess the developmental genetics of sex-specific chemosensation.

  9. MicroRNA-Mediated Reprogramming of Somatic Cells into Induced Pluripotent Stem Cells.

    Science.gov (United States)

    Sandmaier, Shelley E S; Telugu, Bhanu Prakash V L

    2015-01-01

    MicroRNAs or miRNAs belong to a class of small noncoding RNAs that play a crucial role in posttranscriptional regulation of gene expression. Nascent miRNAs are expressed as a longer transcript, which are then processed into a smaller 18-23-nucleotide mature miRNAs that bind to the target transcripts and induce cleavage or inhibit translation. MiRNAs therefore represent another key regulator of gene expression in establishing and maintaining unique cellular fate. Several classes of miRNAs have been identified to be uniquely expressed in embryonic stem cells (ESC) and regulated by the core transcription factors Oct4, Sox2, and Klf4. One such class of miRNAs is the mir-302/367 cluster that is enriched in pluripotent cells in vivo and in vitro. Using the mir-302/367 either by themselves or in combination with the Yamanaka reprogramming factors (Oct4, Sox2, c-Myc, and Klf4) has resulted in the establishment of induced pluripotent stem cells (iPSC) with high efficiencies. In this chapter, we outline the methodologies for establishing and utilizing the miRNA-based tools for reprogramming somatic cells into iPSC.

  10. Identification of miRNAs and miRNA-mediated regulatory pathways in Carica papaya.

    Science.gov (United States)

    Liang, Gang; Li, Yang; He, Hua; Wang, Fang; Yu, Diqiu

    2013-10-01

    Plant microRNAs (miRNAs) post-transcriptionally regulate target gene expression to modulate growth and development and biotic and abiotic stress responses. By analyzing small RNA deep sequencing data in combination with the genome sequence, we identified 75 conserved miRNAs and 11 novel miRNAs. Their target genes were also predicted. For most conserved miRNAs, the miRNA-target pairs were conserved across plant species. In addition to these conserved miRNA-target pairs, we also identified some papaya-specific miRNA-target regulatory pathways. Both miR168 and miR530 target the Argonaute 1 gene, indicating a second autoregulatory mechanism for miRNA regulation. A non-conserved miRNA was mapped within an intron of Dicer-like 1 (DCL1), suggesting a conserved homeostatic autoregulatory mechanism for DCL1 expression. A 21-nt miRNA triggers secondary siRNA production from its target genes, nucleotide-binding site leucine-rich repeat protein genes. Certain phased-miRNAs were processed from their conserved miRNA precursors, indicating a putative miRNA evolution mechanism. In addition, we identified a Carica papaya-specific miRNA that targets an ethylene receptor gene, implying its function in the ethylene signaling pathway. This work will also advance our understanding of miRNA functions and evolution in plants.

  11. From Embryo to Adult: piRNA-Mediated Silencing throughout Germline Development in Drosophila

    Directory of Open Access Journals (Sweden)

    Pauline P. Marie

    2017-02-01

    Full Text Available In metazoan germ cells, transposable element activity is repressed by small noncoding PIWI-associated RNAs (piRNAs. Numerous studies in Drosophila have elucidated the mechanism of this repression in the adult germline. However, when and how transposable element repression is established during germline development has not been addressed. Here, we show that homology-dependent trans silencing is active in female primordial germ cells from late embryogenesis through pupal stages, and that genes related to the adult piRNA pathway are required for silencing during development. In larval gonads, we detect rhino-dependent piRNAs indicating de novo biogenesis of functional piRNAs during development. Those piRNAs exhibit the molecular signature of the “ping-pong” amplification step. Moreover, we show that Heterochromatin Protein 1a is required for the production of piRNAs coming from telomeric transposable elements. Furthermore, as in adult ovaries, incomplete, bimodal, and stochastic repression resembling variegation can occur at all developmental stages. Clonal analysis indicates that the repression status established in embryonic germ cells is maintained until the adult stage, suggesting the implication of a cellular memory mechanism. Taken together, data presented here show that piRNAs and their associated proteins are epigenetic components of a continuous repression system throughout germ cell development.

  12. MicroRNA-mediated interactions between host and hepatitis C virus.

    Science.gov (United States)

    Li, Hu; Jiang, Jian-Dong; Peng, Zong-Gen

    2016-01-28

    MicroRNAs (miRNAs) are small noncoding RNAs. More than 2500 mature miRNAs are detected in plants, animals and several types of viruses. Hepatitis C virus (HCV), which is a positive-sense, single-stranded RNA virus, does not encode viral miRNA. However, HCV infection alters the expression of host miRNAs, either in cell culture or in patients with liver disease progression, such as liver fibrosis, cirrhosis, and hepatocellular carcinoma. In turn, host miRNAs regulate HCV life cycle through directly binding to HCV RNAs or indirectly targeting cellular mRNAs. Increasing evidence demonstrates that miRNAs are one of the centered factors in the interaction network between virus and host. The competitive viral and host RNA hypothesis proposes a latent cross-regulation pattern between host mRNAs and HCV RNAs. High loads of HCV RNA sequester and de-repress host miRNAs from their normal host targets and thus disturb host gene expression, indicating a means of adaptation for HCV to establish a persistent infection. Some special miRNAs are closely correlated with liver-specific disease progression and the changed levels of miRNAs are even higher sensitivity and specificity than those of traditional proteins. Therefore, some of them can serve as novel diagnostic/prognostic biomarkers in HCV-infected patients with liver diseases. They are also attractive therapeutic targets for development of new anti-HCV agents.

  13. The Antiviral and Cancer Genomic DNA Deaminase APOBEC3H Is Regulated by an RNA-Mediated Dimerization Mechanism.

    Science.gov (United States)

    Shaban, Nadine M; Shi, Ke; Lauer, Kate V; Carpenter, Michael A; Richards, Christopher M; Salamango, Daniel; Wang, Jiayi; Lopresti, Michael W; Banerjee, Surajit; Levin-Klein, Rena; Brown, William L; Aihara, Hideki; Harris, Reuben S

    2018-01-04

    Human APOBEC3H and homologous single-stranded DNA cytosine deaminases are unique to mammals. These DNA-editing enzymes function in innate immunity by restricting the replication of viruses and transposons. APOBEC3H also contributes to cancer mutagenesis. Here, we address the fundamental nature of RNA in regulating human APOBEC3H activities. APOBEC3H co-purifies with RNA as an inactive protein, and RNase A treatment enables strong DNA deaminase activity. RNA-binding-defective mutants demonstrate clear separation of function by becoming DNA hypermutators. Biochemical and crystallographic data demonstrate a mechanism in which double-stranded RNA mediates enzyme dimerization. Additionally, APOBEC3H separation-of-function mutants show that RNA binding is required for cytoplasmic localization, packaging into HIV-1 particles, and antiviral activity. Overall, these results support a model in which structured RNA negatively regulates the potentially harmful DNA deamination activity of APOBEC3H while, at the same time, positively regulating its antiviral activity. Copyright © 2017 Elsevier Inc. All rights reserved.

  14. Sign phase transition in the problem of interfering directed paths

    Science.gov (United States)

    Baldwin, C. L.; Laumann, C. R.; Spivak, B.

    2018-01-01

    We investigate the statistical properties of interfering directed paths in disordered media. At long distance, the average sign of the sum over paths may tend to zero (sign disordered) or remain finite (sign ordered) depending on dimensionality and the concentration of negative scattering sites x . We show that in two dimensions the sign-ordered phase is unstable even for arbitrarily small x by identifying rare destabilizing events. In three dimensions, we present strong evidence that there is a sign phase transition at a finite xc>0 . These results have consequences for several different physical systems. In two-dimensional insulators at low temperature, the variable-range-hopping magnetoresistance is always negative, while in three dimensions, it changes sign at the point of the sign phase transition. We also show that in the sign-disordered regime a small magnetic field may enhance superconductivity in a random system of D -wave superconducting grains embedded in a metallic matrix. Finally, the existence of the sign phase transition in three dimensions implies new features in the spin-glass phase diagram at high temperature.

  15. New Insight into Inter-kingdom Communication: Horizontal Transfer of Mobile Small RNAs

    Directory of Open Access Journals (Sweden)

    Xi Chen

    2017-05-01

    Full Text Available Small RNAs (sRNAs, including small interfering RNAs (siRNAs and microRNAs (miRNAs, are conventionally regarded as critical molecular regulators of various intracellular processes. However, recent accumulating evidence indicates that sRNAs can be transferred within cells and tissues and even across species. In plants, nematodes and microbes, these mobile sRNAs can mediate inter-kingdom communication, environmental sensing, gene expression regulation, host-parasite defense and many other biological functions. Strikingly, a recent study by our group suggested that ingested plant miRNAs are transferred to blood, accumulate in tissues and regulate transcripts in consuming animals. While our and other independent groups’ subsequent studies further explored the emerging field of sRNA-mediated crosstalk between species, some groups reported negative results and questioned its general applicability. Thus, further studies carefully evaluating the horizontal transfer of exogenous sRNAs and its potential biological functions are urgently required. Here, we review the current state of knowledge in the field of the horizontal transfer of mobile sRNAs, suggest its future directions and key points for examination and discuss its potential mechanisms and application prospects in nutrition, agriculture and medicine.

  16. A microRNA-mediated regulatory loop modulates NOTCH and MYC oncogenic signals in B- and T-cell malignancies.

    Science.gov (United States)

    Ortega, M; Bhatnagar, H; Lin, A-P; Wang, L; Aster, J C; Sill, H; Aguiar, R C T

    2015-04-01

    Growing evidence suggests that microRNAs (miRNAs) facilitate the cross-talk between transcriptional modules and signal transduction pathways. MYC and NOTCH1 contribute to the pathogenesis of lymphoid malignancies. NOTCH induces MYC, connecting two signaling programs that enhance oncogenicity. Here we show that this relationship is bidirectional and that MYC, via a miRNA intermediary, modulates NOTCH. MicroRNA-30a (miR-30a), a member of a family of miRNAs that are transcriptionally suppressed by MYC, directly binds to and inhibits NOTCH1 and NOTCH2 expression. Using a murine model and genetically modified human cell lines, we confirmed that miR-30a influences NOTCH expression in a MYC-dependent fashion. In turn, through genetic modulation, we demonstrated that intracellular NOTCH1 and NOTCH2, by inducing MYC, suppressed miR-30a. Conversely, pharmacological inhibition of NOTCH decreased MYC expression and ultimately de-repressed miR-30a. Examination of genetic models of gain and loss of miR-30a in diffuse large B-cell lymphoma (DLBCL) and T-acute lymphoblastic leukemia (T-ALL) cells suggested a tumor-suppressive role for this miRNA. Finally, the activity of the miR-30a-NOTCH-MYC loop was validated in primary DLBCL and T-ALL samples. These data define the presence of a miRNA-mediated regulatory circuitry that may modulate the oncogenic signals originating from NOTCH and MYC.

  17. Retracted: siRNA Mediated Silencing of NIN1/RPN12 Binding Protein 1 Homolog Inhibits Proliferation and Growth of Breast Cancer Cells

    Science.gov (United States)

    Huang, Wei-Yi; Chen, Dong-Hui; Ning, Li; Wang, Li-Wei

    2017-10-27

    Retraction: Retracted: siRNA mediated silencing of NIN1/RPN12 binding protein 1 homolog inhibits proliferation and growth of breast cancer cells Asian Pacific Journal of Cancer Prevention has retracted the article titled “siRNA mediated silencing of NIN1/RPN12 binding protein 1 homolog inhibits proliferation and growth of breast cancer cells”(1) for reason of similarity with a series of articles identified by Byrne and Labbé (2). 1. Huang WY1, Chen DH, Ning L, Wang LW. siRNA mediated silencing of NIN1/RPN12 binding protein 1 homolog inhibits proliferation and growth of breast cancer cells. Asian Pac J Cancer Prev. 2012;13(5):1823-7. 2. J. A. Byrne and C. Labbé, “Striking similarities between publications from China describing single gene knockdown experiments in human cancer cell lines,” Scientometrics, vol. 110, no. 3, pp. 1471–1493, 2017. Authors did not respond to request for comment.

  18. High-throughput sequencing as an effective approach in profiling small RNAs derived from a hairpin RNA expression vector in woody plants.

    Science.gov (United States)

    Zhao, Dongyan; Song, Guo-Qing

    2014-11-01

    Hairpin RNA (hpRNA)-mediated gene silencing has proved to be an efficient approach to develop virus-resistant transgenic plants. To characterize small RNA molecules (sRNAs) derived from an hpRNA expression vector in transgenic cherry rootstock plants, we conducted small RNA sequencing of (1) a transgenic rootstock containing an inverted repeat of the partial coat protein of Prunus necrotic ring spot virus (PNRSV-hpRNA); (2) a nontransgenic rootstock; and (3) a PNRSV-infected sweet cherry plant. Analysis of the PNRSV sRNA pools indicated that 24-nt (nucleotide) small interfering RNAs (siRNAs) were the most prevalent sRNAs in the transgenic rootstock whereas the most abundant sRNAs in the PNRSV-infected nontransgenic rootstock were 21-nt siRNAs. In addition, the 24-nt siRNAs of the PNRSV-hpRNA were more abundant on the sense strand than those on the antisense strand in the transgenic rootstock. In contrast, preference in generating PNRSV sRNAs, ranging from 19-nt to 30-nt for sense and antisense strands, was not distinct in the PNRSV-infected nontransgenic sweet cherry. Taken together, this is the first report on profiling hpRNA-derived sRNAs in woody plants using high-throughput sequencing technology, which is an efficient way to verify the presence/absence, the abundance, and the sequence features of certain sRNAs. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  19. Exploring the trans-acting short interfering RNAs (ta-siRNAs) technology for virus control in plants

    Science.gov (United States)

    Small ribonucleic acid (RNAs) (~20-24nt) processed from double-stranded RNA in plants can trigger degradation of the target mRNAs in cytoplasm or de novo DNA methylation in nucleus leading to gene silencing. Trans-acting short-interfering RNAs (ta-siRNAs) have been shown to enhance the target mRNA d...

  20. siRNA-mediated Allele-specific Silencing of a COL6A3 Mutation in a Cellular Model of Dominant Ullrich Muscular Dystrophy

    Directory of Open Access Journals (Sweden)

    Véronique Bolduc

    2014-01-01

    Full Text Available Congenital muscular dystrophy type Ullrich (UCMD is a severe disorder of early childhood onset for which currently there is no effective treatment. UCMD commonly is caused by dominant-negative mutations in the genes coding for collagen type VI, a major microfibrillar component of the extracellular matrix surrounding the muscle fibers. To explore RNA interference (RNAi as a potential therapy for UCMD, we designed a series of small interfering RNA (siRNA oligos that specifically target the most common mutations resulting in skipping of exon 16 in the COL6A3 gene and tested them in UCMD-derived dermal fibroblasts. Transcript analysis by semiquantitative and quantitative reverse transcriptase PCR showed that two of these siRNAs were the most allele-specific, i.e., they efficiently knocked down the expression from the mutant allele, without affecting the normal allele. In HEK293T cells, these siRNAs selectively suppressed protein expression from a reporter construct carrying the mutation, with no or minimal suppression of the wild-type (WT construct, suggesting that collagen VI protein levels are as also reduced in an allele-specific manner. Furthermore, we found that treating UCMD fibroblasts with these siRNAs considerably improved the quantity and quality of the collagen VI matrix, as assessed by confocal microscopy. Our current study establishes RNAi as a promising molecular approach for treating dominant COL6-related dystrophies.

  1. RNA-mediated gene silencing signals are not graft transmissible from the rootstock to the scion in greenhouse-grown apple plants Malus sp.

    Science.gov (United States)

    Flachowsky, Henryk; Tränkner, Conny; Szankowski, Iris; Waidmann, Sascha; Hanke, Magda-Viola; Treutter, Dieter; Fischer, Thilo C

    2012-01-01

    RNA silencing describes the sequence specific degradation of RNA targets. Silencing is a non-cell autonomous event that is graft transmissible in different plant species. The present study is the first report on systemic acquired dsRNA-mediated gene silencing of transgenic and endogenous gene sequences in a woody plant like apple. Transgenic apple plants overexpressing a hairpin gene construct of the gusA reporter gene were produced. These plants were used as rootstocks and grafted with scions of the gusA overexpressing transgenic apple clone T355. After grafting, we observed a reduction of the gusA gene expression in T355 scions in vitro, but not in T355 scions grown in the greenhouse. Similar results were obtained after silencing of the endogenous Mdans gene in apple that is responsible for anthocyanin biosynthesis. Subsequently, we performed grafting experiments with Mdans silenced rootstocks and red leaf scions of TNR31-35 in order to evaluate graft transmitted silencing of the endogenous Mdans. The results obtained suggested a graft transmission of silencing signals in in vitro shoots. In contrast, no graft transmission of dsRNA-mediated gene silencing signals was detectable in greenhouse-grown plants and in plants grown in an insect protection tent.

  2. DAZL relieves miRNA-mediated repression of germline mRNAs by controlling poly(A tail length in zebrafish.

    Directory of Open Access Journals (Sweden)

    Yasuaki Takeda

    Full Text Available BACKGROUND: During zebrafish embryogenesis, microRNA (miRNA miR-430 contributes to restrict Nanos1 and TDRD7 to primordial germ cells (PGCs by inducing mRNA deadenylation, mRNA degradation, and translational repression of nanos1 and tdrd7 mRNAs in somatic cells. The nanos1 and tdrd7 3'UTRs include cis-acting elements that allow activity in PGCs even in the presence of miRNA-mediated repression. METHODOLOGY/PRINCIPAL FINDINGS: Using a GFP reporter mRNA that was fused with tdrd7 3'UTR, we show that a germline-specific RNA-binding protein DAZ-like (DAZL can relieve the miR-430-mediated repression of tdrd7 mRNA by inducing poly(A tail elongation (polyadenylation in zebrafish. We also show that DAZL enhances protein synthesis via the 3'UTR of dazl mRNA, another germline mRNA targeted by miR-430. CONCLUSIONS/SIGNIFICANCE: Our present study indicated that DAZL acts as an "anti-miRNA factor" during vertebrate germ cell development. Our data also suggested that miRNA-mediated regulation can be modulated on specific target mRNAs through the poly(A tail control.

  3. Ubiquitous expression of CUG or CAG trinucleotide repeat RNA causes common morphological defects in a Drosophila model of RNA-mediated pathology.

    Directory of Open Access Journals (Sweden)

    Kynan T Lawlor

    Full Text Available Expanded DNA repeat sequences are known to cause over 20 diseases, including Huntington's disease, several types of spinocerebellar ataxia and myotonic dystrophy type 1 and 2. A shared genetic basis, and overlapping clinical features for some of these diseases, indicate that common pathways may contribute to pathology. Multiple mechanisms, mediated by both expanded homopolymeric proteins and expanded repeat RNA, have been identified by the use of model systems, that may account for shared pathology. The use of such animal models enables identification of distinct pathways and their 'molecular hallmarks' that can be used to determine the contribution of each pathway in human pathology. Here we characterise a tergite disruption phenotype in adult flies, caused by ubiquitous expression of either untranslated CUG or CAG expanded repeat RNA. Using the tergite phenotype as a quantitative trait we define a new genetic system in which to examine 'hairpin' repeat RNA-mediated cellular perturbation. Further experiments use this system to examine whether pathways involving Muscleblind sequestration or Dicer processing, which have been shown to mediate repeat RNA-mediated pathology in other model systems, contribute to cellular perturbation in this model.

  4. Spin O decay angular distribution for interfering mesons in electroproduction

    Energy Technology Data Exchange (ETDEWEB)

    Funsten, H.; Gilfoyle, G.

    1994-04-01

    Self analyzing meson electroproduction experiments are currently being planned for the CEBAF CLAS detector. These experiments deduce the spin polarization of outgoing unstable spin s (?)0 mesons from their decay angular distribution, W({theta},{psi}). The large angular acceptance of the CLAS detector permits kinematic tracking of a sufficient number of these events to accurately determine electroproduction amplitudes from the deduced polarization. Maximum polarization information is obtained from W({theta},{psi}) for decay into spin 0 daughters. The helicity of the decaying meson is transferred to the daughter`s relative orbital angular momentum m-projection; none is {open_quotes}absorbed{close_quotes} into daughter helicities. The decaying meson`s helicity maximally appears in W({theta},{psi}). W({theta},{psi}) for spin 0 daughters has been derived for (1) vector meson electroproduction and (2) general interfering mesons produced by incident pions. This paper derives W({theta},{psi}) for electroproduction of two interfering mesons that decay into spin 0 daughters. An application is made to the case of interfering scalar and vector mesons. The derivation is an extension of work by Schil using the general decay formalism of Martin. The expressions can be easily extended to the case of N interfering mesons since interference occurs pairwise in the observable W ({theta},{psi}), a quadratic function of the meson amplitudes. The derivation uses the virtual photon density matrix of Schil which is transformed by a meson electroproduction transition operator, T. The resulting density matrix for the interfering mesons is then converted into a corresponding statistical tensor and contracted into the efficiency tensor for spin 0 daughters.

  5. Spin O decay angular distribution for interfering mesons in electroproduction

    International Nuclear Information System (INIS)

    Funsten, H.; Gilfoyle, G.

    1994-01-01

    Self analyzing meson electroproduction experiments are currently being planned for the CEBAF CLAS detector. These experiments deduce the spin polarization of outgoing unstable spin s (?)0 mesons from their decay angular distribution, W(θ,ψ). The large angular acceptance of the CLAS detector permits kinematic tracking of a sufficient number of these events to accurately determine electroproduction amplitudes from the deduced polarization. Maximum polarization information is obtained from W(θ,ψ) for decay into spin 0 daughters. The helicity of the decaying meson is transferred to the daughter's relative orbital angular momentum m-projection; none is open-quotes absorbedclose quotes into daughter helicities. The decaying meson's helicity maximally appears in W(θ,ψ). W(θ,ψ) for spin 0 daughters has been derived for (1) vector meson electroproduction and (2) general interfering mesons produced by incident pions. This paper derives W(θ,ψ) for electroproduction of two interfering mesons that decay into spin 0 daughters. An application is made to the case of interfering scalar and vector mesons. The derivation is an extension of work by Schil using the general decay formalism of Martin. The expressions can be easily extended to the case of N interfering mesons since interference occurs pairwise in the observable W (θ,ψ), a quadratic function of the meson amplitudes. The derivation uses the virtual photon density matrix of Schil which is transformed by a meson electroproduction transition operator, T. The resulting density matrix for the interfering mesons is then converted into a corresponding statistical tensor and contracted into the efficiency tensor for spin 0 daughters

  6. From early lessons to new frontiers: the worm as a treasure trove of small RNA biology.

    Science.gov (United States)

    Youngman, Elaine M; Claycomb, Julie M

    2014-01-01

    In the past 20 years, the tiny soil nematode Caenorhabditis elegans has provided critical insights into our understanding of the breadth of small RNA-mediated gene regulatory activities. The first microRNA was identified in C. elegans in 1993, and the understanding that dsRNA was the driving force behind RNA-mediated gene silencing came from experiments performed in C. elegans in 1998. Likewise, early genetic screens in C. elegans for factors involved in RNA interference pointed to conserved mechanisms for small RNA-mediated gene silencing pathways, placing the worm squarely among the founding fathers of a now extensive field of molecular biology. Today, the worm continues to be at the forefront of ground-breaking insight into small RNA-mediated biology. Recent studies have revealed with increasing mechanistic clarity that C. elegans possesses an extensive nuclear small RNA regulatory network that encompasses not only gene silencing but also gene activating roles. Further, a portrait is emerging whereby small RNA pathways play key roles in integrating responses to environmental stimuli and transmitting epigenetic information about such responses from one generation to the next. Here we discuss endogenous small RNA pathways in C. elegans and the insight worm biology has provided into the mechanisms employed by these pathways. We touch on the increasingly spectacular diversity of small RNA biogenesis and function, and discuss the relevance of lessons learned in the worm for human biology.

  7. From early lessons to new frontiers: The worm as a treasure trove of small RNA biology

    Directory of Open Access Journals (Sweden)

    Elaine M. Youngman

    2014-11-01

    Full Text Available In the past twenty years, the tiny soil nematode C. elegans has provided critical insights into our understanding of the breadth of small RNA-mediated gene regulatory activities. The first microRNA was identified in C. elegans in 1993, and the understanding that dsRNA was the driving force behind RNA-mediated gene silencing came from experiments performed in C. elegans in 1998. Likewise, early genetic screens in C. elegans for factors involved in RNAi pointed to conserved mechanisms for small RNA-mediated gene silencing pathways, placing the worm squarely among the founding fathers of a now extensive field of molecular biology. Today, the worm continues to be at the forefront of ground-breaking insight into small RNA-mediated biology. Recent studies have revealed with increasing mechanistic clarity that C. elegans possesses an extensive nuclear small RNA regulatory network that encompasses not only gene silencing but also gene activating roles. Further, a portrait is emerging whereby small RNA pathways play key roles in integrating responses to environmental stimuli and transmitting epigenetic information about such responses from one generation to the next. Here we discuss endogenous small RNA pathways in C. elegans and the insight worm biology has provided into the mechanisms employed by these pathways. We touch on the increasingly spectacular diversity of small RNA biogenesis and function, and discuss the relevance of lessons learned in the worm for human biology.

  8. [Effects on survival of shRNA mediated APE/Ref1 gene silencing in rat spiral ganglion cells in oxidative stress].

    Science.gov (United States)

    Jiang, Zhendong; Zhong, Cheng; Li, Taijun; Xiang, Zhaolan; Zhang, Xueyuan

    2014-02-01

    To investigate the effects of reducing APE/Ref1 expression in the cultures of rat spiral ganglion cells with oxidative damage induced by H(2)O(2). Primary cultured rat spiral ganglion cells were infected with small interfering RNA to APE/Ref1 (Ape1siRNA) for 72 h, followed by treating with H(2)O(2) (0, 10, 25, 50, 100 and 300 µmol/L) for 1 h , and then cultured in normal medium for 24 h. Western blot were used to detect the level of APE/Ref1 protein and phosphorylation of histone protein H2AX in the infected cells. The caspase3 activation was tested by spectrophotometric method . The cell viability was determined by MTT and the apoptosis of spiral ganglion cells was determined by terminal-deoxynucleotidyl transferase mediated nick and labeling (TUNEL). Western blot showed that infection with Ape1siRNA resulted in APE/Ref1 reduced expression in the spiral ganglion cells. Exposing spiral ganglion cultures with reduced expression of APE/Ref1 to H(2)O(2) (50, 100, 300 µmol/L) for 1 h resulted in increasing in the phosphorylation of histone protein H2AX. The reduction in APE/Ref1 significantly reduced cell viability in cultures 24 h after 1 h expression to 50-300 µmol/L H(2)O(2). The apoptosis of cells and caspase 3 activity was detected significantly improved. The induced of APE/Ref1 results in significantly decrease in spiral ganglion cells viability in oxidative stress. The repairing function of APE/Ref1 is necessary for optimal levels of neuronal rat spiral ganglion cells survival.

  9. Effects of shRNA-Mediated Silencing of PKM2 Gene on Aerobic Glycolysis, Cell Migration, Cell Invasion, and Apoptosis in Colorectal Cancer Cells.

    Science.gov (United States)

    Yan, Xiao-Ling; Zhang, Xue-Bin; Ao, Ran; Guan, Lin

    2017-12-01

    This study aims to explore the effects of shRNA-mediated silencing on Pyruvate kinase type M2 (PKM2) gene during aerobic glycolysis in colorectal cancer (CRC) cells. CRC tissues and adjacent normal tissues were obtained from 136 patients diagnosed with qRT-PCR, Western blotting, and immunohistochemistry (IHC) were performed to detect mRNA and protein expressions of PKM2. CRC cells were divided into a blank, vector, and PKM2-shRNA groups. Hexokinase (HK) and PKM2 activity were both determined by glucose-6-phosphate dehydrogenase (G-6-PD) coupled colorimetric assay and enzyme coupling rate method. The extracellular lactate concentration was measured by ultraviolet spectrophotometer and caspase activity was measured using spectrophotometry. The proliferation, cell cycle, apoptosis, invasion, and migration of CRC cells were detected by cell counting kit-8 (CCK-8) assay, flow cytometry, transwell assay, and scratch test. Three groups of nude mice were injected with 0.2 mL single-cell suspension from the blank, vector, and PKM2-shRNA groups, respectively. PKM2 protein content in CRC tissues was higher than that in adjacent normal tissues. Results showed that the PKM2-shRNA group exhibited significantly lower mRNA and protein expressions of PKM2, decreased PKM2 activity, reduced lactate metabolism level, increased cell apoptosis rate, elevated caspase-3 and caspase-9 activity, weakened proliferation, and a reduction in cell invasion and migration ability compared to the vector and blank groups. The optical density (OD) value was lower in the PKM2-shRNA group than in the blank and vector groups. These findings indicate that shRNA-mediated silencing of PKM2 gene promotes apoptosis and inhibits aerobic glycolysis, proliferation, migration, and invasion in CRC cells. J. Cell. Biochem. 118: 4792-4803, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  10. Interferência das estatinas em exames laboratoriais

    Directory of Open Access Journals (Sweden)

    Danyelle Cristine MARINI

    2017-01-01

    Full Text Available Medicamentos assume importante papel na rotina laboratorial das Análises Clinicas, pela probabilidade de interferir nos ensaios e modificar o diagnóstico clínico-laboratorial. Cabe ao profissional analista clínico responsável detectar essas interferências a fim de evitar diagnósticos equivocados e intervenções clínicas errôneas. O objetivo do trabalho foi avaliar as possíveis interferências do fármaco sinvastatina nos exames laboratoriais bioquímicos. Foi realizado um estudo descritivo retrospectivo, no período de abril a julho de 2015. Foram avaliados os exames laboratoriais realizados pelos pacientes portadores de dislipidemia e usuários de medicamento específico, que utilizaram os serviços prestados pelo Laboratório Municipal de Análises Clínicas de Santo Antônio de Posse (SP. Aos participantes voluntários foi aplicado um questionário para avaliar o estilo de vida e o tempo de uso do medicamento. Foram analisadas as enzimas Fosfatase Alcalina, Creatinofosfoquinase (CPK, Aspartato Aminotransferase (AST e Alanina lminotransferase (ALT. O estudo mostrou que dos 43 pacientes avaliados, 69,8% apresentaram alterações em pelo menos um dos exames avaliados. Foi observada alteração da enzima ALT em 53% dos pacientes avaliados e nenhuma modificação no valor da CPK em 51% dos sujeitos. As interferências nos resultados de exames causadas por fármacos é um problema real, devido à grande utilização por toda a população, e comprova a necessidade de mais estudos relacionados às possíveis interferências nos exames clínicos.

  11. Two-Pronged Approach to Overcome Spectroscopically Interfering Organic Compounds with Isotopic Water Analysis

    Science.gov (United States)

    Saad, Nabil; Hsiao, Gregor; Chapellet-Volpini, London; Vu, Danthu

    2013-04-01

    The ability to measure the stable isotopes of hydrogen (dD) and oxygen (d18O) has become much more accessible with the advent of Cavity Ring-Down Spectroscopy (CRDS) laser optical devices. These small and inexpensive analyzers have led to a significant increase in the acquisition of data from a variety of studies in the fields of groundwater, watershed, and other water source applications. However for some samples, such as those linked to fracking, mining, and other activities where higher than normal concentrations of organic materials are to be found, optical spectroscopy may require an adaptation from current methodologies in order to ensure data confidence. That is because CRDS is able to measure all the components within a spectral region - which will include the spectral characteristics of the isotopologues of water as well as the available features from interfering organic molecules. Although, at the first level, the information from the organic material provides spectral overlaps that can perturb the isotopic ratios, a more thorough review shows that these features are a source of information that will be inherently useful. This presentation will examine the approaches developed within the past year to allow for more accurate analyses of such samples by optical methods. The first approach uses an advanced spectroscopic model to flag the presence of organic material in the sample. Signals from known interfering compounds (i.e., alcohols, ketones, aldehydes, short-chain hydrocarbons, etc.) are incorporated into the overall fit of the measured spectra used to calculate the concentration of the individual isotopes. The second approach uses physical treatment of the sample to break down the organic molecules into non-interfering species. The vaporized liquid or solid sample travels through a cartridge packed with an oxidation catalyst. The interfering organic molecules will undergo high temperature oxidation using O2 present in the air carrier gas stream prior

  12. MicroRNA-Mediated Rescue of Fear Extinction Memory by miR-144-3p in Extinction-Impaired Mice.

    Science.gov (United States)

    Murphy, Conor P; Li, Xiang; Maurer, Verena; Oberhauser, Michael; Gstir, Ronald; Wearick-Silva, Luis Eduardo; Viola, Thiago Wendt; Schafferer, Simon; Grassi-Oliveira, Rodrigo; Whittle, Nigel; Hüttenhofer, Alexander; Bredy, Timothy W; Singewald, Nicolas

    2017-06-15

    MicroRNA (miRNA)-mediated control of gene expression suggests that miRNAs are interesting targets and/or biomarkers in the treatment of anxiety- and trauma-related disorders, where often memory-associated gene expression is adversely affected. The role of miRNAs in the rescue of impaired fear extinction was assessed using the 129S1/SvlmJ (S1) mouse model of impaired fear extinction. miRNA microarray analysis, reverse transcription polymerase chain reaction, fluorescent in situ hybridization, lentiviral overexpression, and Luciferase reporter assays were used to gain insight into the mechanisms underlying miRNA-mediated normalization of deficient fear extinction. Rescuing impaired fear extinction via dietary zinc restriction was associated with differential expression of miRNAs in the amygdala. One candidate, miR-144-3p, robustly expressed in the basolateral amygdala, showed specific extinction-induced, but not fear-induced, increased expression in both extinction-rescued S1 mice and extinction-intact C57BL/6 (BL6) mice. miR-144-3p upregulation and effects on subsequent behavioral adaption was assessed in S1 and BL6 mice. miR-144-3p overexpression in the basolateral amygdala rescued impaired fear extinction in S1 mice, led to enhanced fear extinction acquisition in BL6 mice, and furthermore protected against fear renewal in BL6 mice. miR-144-3p targets a number of genes implicated in the control of plasticity-associated signaling cascades, including Pten, Spred1, and Notch1. In functional interaction studies, we revealed that the miR-144-3p target, PTEN, colocalized with miR-144-3p in the basolateral amygdala and showed functional downregulation following successful fear extinction in S1 mice. These findings identify a fundamental role of miR-144-3p in the rescue of impaired fear extinction and suggest this miRNA as a viable target in developing novel treatments for posttraumatic stress disorder and related disorders. Copyright © 2017 Society of Biological

  13. Short-hairpin RNA-mediated Heat shock protein 90 gene silencing inhibits human breast cancer cell growth in vitro and in vivo

    International Nuclear Information System (INIS)

    Zuo, Keqiang; Li, Dan; Pulli, Benjamin; Yu, Fei; Cai, Haidong; Yuan, Xueyu; Zhang, Xiaoping; Lv, Zhongwei

    2012-01-01

    Highlights: ► Hsp90 is over-expressed in human breast cancer. ► The shRNA-mediated gene silencing of Hsp90 resulted in inhibition of cell growth. ► Akt and NF-kB were down-regulation after transfection due to Hsp90 silencing. ► The tumor growth ratio was decline due to Hsp90 silencing. ► The PCNA expression was down-regulation due to Hsp90 silencing. -- Abstract: Hsp90 interacts with proteins that mediate signaling pathways involved in the regulation of essential processes such as proliferation, cell cycle control, angiogenesis and apoptosis. Hsp90 inhibition is therefore an attractive strategy for blocking abnormal pathways that are crucial for cancer cell growth. In the present study, the role of Hsp90 in human breast cancer MCF-7 cells was examined by stably silencing Hsp90 gene expression with an Hsp90-silencing vector (Hsp90-shRNA). RT-PCR and Western blot analyses showed that Hsp90-shRNA specifically and markedly down-regulated Hsp90 mRNA and protein expression. NF-kB and Akt protein levels were down-regulated in Hsp90-shRNA transfected cells, indicating that Hsp90 knockout caused a reduction of survival factors and induced apoptosis. Treatment with Hsp90-shRNA significantly increased apoptotic cell death and caused cell cycle arrest in the G1/S phase in MCF-7 cells, as shown by flow cytometry. Silencing of Hsp90 also reduced cell viability, as determined by MTT assay. In vivo experiments showed that MCF-7 cells stably transfected with Hsp90-shRNA grew slowly in nude mice as compared with control groups. In summary, the Hsp90-shRNA specifically silenced the Hsp90 gene, and inhibited MCF-7 cell growth in vitro and in vivo. Possible molecular mechanisms underlying the effects of Hsp90-shRNA include the degradation of Hsp90 breast cancer-related client proteins, the inhibition of survival signals and the upregulation of apoptotic pathways. shRNA-mediated interference may have potential therapeutic utility in human breast cancer.

  14. tmRNA-mediated trans-translation as the major ribosome rescue system in a bacterial cell

    Directory of Open Access Journals (Sweden)

    Hyouta eHimeno

    2014-04-01

    Full Text Available tmRNA (transfer messenger RNA; also known as 10Sa RNA or SsrA RNA is a small RNA molecule that is conserved among bacteria. It has structural and functional similarities to tRNA: it has an upper half of the tRNA-like structure, its 5’ end is processed by RNase P, it has typical tRNA-specific base modifications, it is aminoacylated with alanine, it binds to EF-Tu after aminoacylation and it enters the ribosome with EF-Tu and GTP. However, tmRNA lacks an anticodon, and instead it has a coding sequence for a short peptide called tag-peptide. An elaborate interplay of actions of tmRNA as both tRNA and mRNA with the help of a tmRNA-binding protein, SmpB, facilitates trans-translation, which produces a single polypeptide from two mRNA molecules. Initially alanyl-tmRNA in complex with EF-Tu and SmpB enters the vacant A-site of the stalled ribosome like aminoacyl-tRNA but without a codon-anticodon interaction, and subsequently truncated mRNA is replaced with the tag-encoding region of tmRNA. During these processes, not only tmRNA but also SmpB structurally and functionally mimics both tRNA and mRNA. Thus trans-translation rescues the stalled ribosome, thereby allowing recycling of the ribosome. Since the tag-peptide serves as a target of AAA+ proteases, the trans-translation products are preferentially degraded so that they do not accumulate in the cell. Although alternative rescue systems have recently been revealed, trans-translation is the only system that universally exists in bacteria. Furthermore, it is unique in that it employs a small RNA and that it prevents accumulation of nonfunctional proteins from truncated mRNA in the cell. It might play the major role in rescuing the stalled translation in the bacterial cell.

  15. SiRNA-mediated IGF-1R inhibition sensitizes human colon cancer SW480 cells to radiation

    International Nuclear Information System (INIS)

    Yavari, Kamal; Taghikhani, Mohammad; Mesbah-Namin, Seyed A.; Maragheh, Mohammad Ghannadi; Babaei, Mohammad Hosein; Arfaee, Ali Jabbary; Madani, Hossein; Mirzaei, Hamid Reza

    2010-01-01

    Purpose. Insulin like growth factor receptor 1 (IGF-1R) is well-documented to play a key role in radiation response and tumor radiosensitivity, thus offering an attractive clinic drug target to enhance tumor sensitivity to anti-cancer radiotherapy. Material and methods. Human colon carcinoma SW480 cells were transfected with the specific small interference RNA (siRNA) expression vector (pkD-shRNA-IGF-1R-V2) designed to target IGF-1R mRNA. The expression of IGF-1R mRNA and its protein among the transfected and untransfected cells were detected by semi-quantitative RT-PCR and ELISA assay. The changes in cell radiosensitivity were examined by MTT assay. Results. Transfection of mammalian expression vector pkD containing IGF-1R siRNA was shown to reduce IGF-1R mRNA levels by up to 95%. ELISA assay detected a similar inhibition of IGF-1R protein levels in cells transfected with IGF-1R siRNA. SW480 cells transfected with the expression vector for siRNA significantly rendered cells more sensitive to radiation and the highest radiation enhancement ratio was 2.02 ± 0.08. Conclusion. These data provide the first evidence that specific siRNA fragment (pkD-shRNA-IGF-1R-V2) targeting human IGF-1R mRNA is able to enhance colon cancer radiosensitivity. Also results indicated that, combining IGF-1R siRNA and radiation significantly enhances antitumor efficacy compared with either modality alone

  16. SaRNA-mediated activation of TRPV5 reduces renal calcium oxalate deposition in rat via decreasing urinary calcium excretion.

    Science.gov (United States)

    Zeng, Tao; Duan, Xiaolu; Zhu, Wei; Liu, Yang; Wu, Wenqi; Zeng, Guohua

    2017-08-03

    Hypercalciuria is a main risk factor for kidney stone  formation. TRPV5 is the gatekeeper protein for mediating calcium transport and reabsorption in the kidney. In the present study, we tested the effect of TRPV5 activation with small activating RNA (saRNA), which could induce gene expression by targeting the promoter of the gene, on ethylene glycol (EG)-induced calcium oxalate (CaOx) crystals formation in rat kidney. Five pairs of RNA activation sequences targeting the promoter of rat TRPV5 were designed and synthesized. The synthesized saRNA with the strongest activating effect was selected, and transcellular calcium transportation was tested by Fura-2 analysis. Subsequently, Sprague-Dawley rats were equally divided into three groups and fed with water, 1% EG for 28 days after injecting the negative control saRNA, 1% EG for 28 days after injecting the selected TRPV5-saRNA, respectively. The CaOx crystal formation and the 24-h urine components were assessed. In vitro study, saRNA ds-320 could significantly activate the expression of TRPV5 and transcellular calcium transportation. In vivo study, after 28 days treatment of EG, rats pre-infected with saRNA ds-320 had lower urinary calcium excretion and renal CaOx crystals formation as compared to that pre-infected with negative control saRNA. Activation of TRVP5 with saRNA ds-320 could inhibit EG-induced calcium oxalate crystals formation via promoting urine calcium reabsorption and decreasing urine calcium excretion in rats.

  17. shRNA-mediated AMBRA1 knockdown reduces the cisplatin-induced autophagy and sensitizes ovarian cancer cells to cisplatin.

    Science.gov (United States)

    Li, Xiaoyan; Zhang, Lijuan; Yu, Lili; Wei, Wei; Lin, Xueyan; Hou, Xiaoman; Tian, Yongjie

    2016-02-01

    Recent research has revealed a role for Ambra1, an autophagy-related gene-related (ATG) protein, in the autophagic pro-survival response, and Ambra1 has been shown to regulate Beclin1 and Beclin1-dependent autophagy in embryonic stem cells and cancer cells. However, whether Ambra1 plays an important role in the autophagy pathway in ovarian cancer cells is unknown. In this study, we hypothesized that Ambra1 is an important regulator of autophagy and apoptosis in ovarian cancer cells. We firstly confirmed autophagic activity in ovarian cancer OVCAR-3 cells which were treated with cisplatin by assessing endogenous microtubule-associated protein 1 light chain 3 (LC3) localization and the presence of autophagosomes and LC3 protein levels in OVCAR-3 cells. Cell apoptosis and viability were measured by annexin-V and PI staining and MTT assays. We then knocked down Ambra1 expression with transfection with the plasmid expressing the small hairpin RNA (shRNA) targeting AMBRA1, then re-evaluated autophagy in the OVCAR-3 cells subject to cisplatin treatment, and re-determined the sensitivity of OVCAR-3 cells to cisplatin. Results demonstrated that cisplatin treatment induced autophagy in OVCAR-3 cells in association with Ambra1 upregulation in the ovarian cancer cells. When Ambra1 expression was reduced by shRNA, the ovarian cancer cells were more sensitive to cisplatin. In conclusion, Ambra1 is a crucial regulator of autophagy and apoptosis in ovarian cancer cells subject to cisplatin to maintain the balance between autophagy and apoptosis. And the Ambra1-targeting inhibition might be an effective method to sensitize ovarian cancer cells to chemotherapy.

  18. β2-Adrenergic receptor agonist ameliorates phenotypes and corrects microRNA-mediated IGF1 deficits in a mouse model of Rett syndrome

    Science.gov (United States)

    Mellios, Nikolaos; Woodson, Jonathan; Garcia, Rodrigo I.; Crawford, Benjamin; Sharma, Jitendra; Sheridan, Steven D.; Haggarty, Stephen J.; Sur, Mriganka

    2014-01-01

    Rett syndrome is a severe childhood onset neurodevelopmental disorder caused by mutations in methyl-CpG–binding protein 2 (MECP2), with known disturbances in catecholamine synthesis. Here, we show that treatment with the β2-adrenergic receptor agonist clenbuterol increases survival, rescues abnormalities in respiratory function and social recognition, and improves motor coordination in young male Mecp2-null (Mecp2−/y) mice. Importantly, we demonstrate that short-term treatment with clenbuterol in older symptomatic female heterozygous (Mecp2−/+) mice rescues respiratory, cognitive, and motor coordination deficits, and induces an anxiolytic effect. In addition, we reveal abnormalities in a microRNA-mediated pathway, downstream of brain-derived neurotrophic factor that affects insulin-like growth factor 1 (IGF1) expression in Mecp2−/y mice, and show that treatment with clenbuterol restores the observed molecular alterations. Finally, cotreatment with clenbuterol and recombinant human IGF1 results in additional increases in survival in male null mice. Collectively, our data support a role for IGF1 and other growth factor deficits as an underlying mechanism of Rett syndrome and introduce β2-adrenergic receptor agonists as potential therapeutic agents for the treatment of the disorder. PMID:24958851

  19. Tomato chlorotic mottle virus is a target of RNA silencing but the presence of specific short interfering RNAs does not guarantee resistance in transgenic plants

    NARCIS (Netherlands)

    Ribeiro, S.G.; Lohuis, H.; Goldbach, R.W.; Prins, M.

    2007-01-01

    Tomato chlorotic mottle virus (ToCMoV) is a begomovirus found widespread in tomato fields in Brazil. ToCMoV isolate BA-Se1 (ToCMoV-[BA-Se1]) was shown to trigger the plant RNA silencing surveillance in different host plants and, coinciding with a decrease in viral DNA levels, small interfering RNAs

  20. A self-interfering clock as a "which path" witness.

    Science.gov (United States)

    Margalit, Yair; Zhou, Zhifan; Machluf, Shimon; Rohrlich, Daniel; Japha, Yonathan; Folman, Ron

    2015-09-11

    In Einstein's general theory of relativity, time depends locally on gravity; in standard quantum theory, time is global-all clocks "tick" uniformly. We demonstrate a new tool for investigating time in the overlap of these two theories: a self-interfering clock, comprising two atomic spin states. We prepare the clock in a spatial superposition of quantum wave packets, which evolve coherently along two paths into a stable interference pattern. If we make the clock wave packets "tick" at different rates, to simulate a gravitational time lag, the clock time along each path yields "which path" information, degrading the pattern's visibility. In contrast, in standard interferometry, time cannot yield "which path" information. This proof-of-principle experiment may have implications for the study of time and general relativity and their impact on fundamental effects such as decoherence and the emergence of a classical world. Copyright © 2015, American Association for the Advancement of Science.

  1. Defective interfering particles in monolayer-propagated Newcastle disease virus

    International Nuclear Information System (INIS)

    Roman, J.M.; Simon, E.H.

    1976-01-01

    Newcastle disease virus (NDV) serially passaged in chick embryo fibroblasts (M-NDV) gives rise to defective interfering (NDV-DI) particles, while NDV passaged in embryonated eggs (E-NDV) does not. Co-infection with these particles and infectious virions results in a 99 percent reduction in yield. Interference is not due to interferon or to prevention of absorption of infectious virions and is specific for NDV. The particles mediating interference sediment at the same velocity as infectious virions. The accumulation of NDV-DI particles in monolayers but not in eggs may be a consequence of the fact that M-NDV virions are larger and probably contain more RNA, or it may reflect differences in NDV replicative processes in eggs and monolayers, or both

  2. High molecular somatostatin, an interfering factor in radioimmunoassay

    International Nuclear Information System (INIS)

    Diel, F.; Schneider, E.; Baumann, H.

    1977-01-01

    Cyclic Tyr 1 -somatostatin (Tyr 1 -SRIF) is radioiodinated by the lactoperoxidase method. Purification is achieved by Sephadex G-25 adsorption chromatography. Specific anti-SRIF serum (FA1) has been raised in rabbits. A dose response curve is obtained in the range of 5 - 5,000 pg per tube using an antiserum dilution of 1:2,000. There is little cross-reaction with linear somatostatin and none with ocytocin, (lys-, arg-) vasopressin, valinomycin, polymyxin, insulin, glucagon, human growth hormone (hGH), and thyrotropin-releasing hormone (TRH). For recovery tests, extraction procedures are necessary. Thin-layer chromatography (TLC) and polyacrylamide-disc-electrophoresis (Disc-PAGE) are performed to identify the presumed high molecular 125 I-Tyr 1 -SRIF associate. This high molecular associate may represent an interfering factor in the radioimmunoassay for cyclic SRIF. (orig./AJ) [de

  3. Sustained miRNA-mediated knockdown of mutant AAT with simultaneous augmentation of wild-type AAT has minimal effect on global liver miRNA profiles.

    Science.gov (United States)

    Mueller, Christian; Tang, Qiushi; Gruntman, Alisha; Blomenkamp, Keith; Teckman, Jeffery; Song, Lina; Zamore, Phillip D; Flotte, Terence R

    2012-03-01

    α-1 antitrypsin (AAT) deficiency can exhibit two pathologic states: a lung disease that is primarily due to the loss of AAT's antiprotease function, and a liver disease resulting from a toxic gain-of-function of the PiZ-AAT (Z-AAT) mutant protein. We have developed several recombinant adeno-associated virus (rAAV) vectors that incorporate microRNA (miRNA) sequences targeting the AAT gene while also driving the expression of miRNA-resistant wild-type AAT-PiM (M-AAT) gene, thus achieving concomitant Z-AAT knockdown in the liver and increased expression of M-AAT. Transgenic mice expressing the human PiZ allele treated with dual-function rAAV9 vectors showed that serum PiZ was stably and persistently reduced by an average of 80%. Treated animals showed knockdown of Z-AAT in liver and serum with concomitant increased serum M-AAT as determined by allele-specific enzyme-linked immunosorbent assays (ELISAs). In addition, decreased globular accumulation of misfolded Z-AAT in hepatocytes and a reduction in inflammatory infiltrates in the liver was observed. Results from microarray studies demonstrate that endogenous miRNAs were minimally affected by this treatment. These data suggests that miRNA mediated knockdown does not saturate the miRNA pathway as has been seen with viral vector expression of short hairpin RNAs (shRNAs). This safe dual-therapy approach can be applied to other disorders such as amyotrophic lateral sclerosis, Huntington disease, cerebral ataxia, and optic atrophies.

  4. Small RNAs and the regulation of cis-natural antisense transcripts in Arabidopsis

    Directory of Open Access Journals (Sweden)

    Lonardi Stefano

    2008-01-01

    Full Text Available Abstract Background In spite of large intergenic spaces in plant and animal genomes, 7% to 30% of genes in the genomes encode overlapping cis-natural antisense transcripts (cis-NATs. The widespread occurrence of cis-NATs suggests an evolutionary advantage for this type of genomic arrangement. Experimental evidence for the regulation of two cis-NAT gene pairs by natural antisense transcripts-generated small interfering RNAs (nat-siRNAs via the RNA interference (RNAi pathway has been reported in Arabidopsis. However, the extent of siRNA-mediated regulation of cis-NAT genes is still unclear in any genome. Results The hallmarks of RNAi regulation of NATs are 1 inverse regulation of two genes in a cis-NAT pair by environmental and developmental cues and 2 generation of siRNAs by cis-NAT genes. We examined Arabidopsis transcript profiling data from public microarray databases to identify cis-NAT pairs whose sense and antisense transcripts show opposite expression changes. A subset of the cis-NAT genes displayed negatively correlated expression profiles as well as inverse differential expression changes under at least one of the examined developmental stages or treatment conditions. By searching the Arabidopsis Small RNA Project (ASRP and Massively Parallel Signature Sequencing (MPSS small RNA databases as well as our stress-treated small RNA dataset, we found small RNAs that matched at least one gene in 646 pairs out of 1008 (64% protein-coding cis-NAT pairs, which suggests that siRNAs may regulate the expression of many cis-NAT genes. 209 putative siRNAs have the potential to target more than one gene and half of these small RNAs could target multiple members of a gene family. Furthermore, the majority of the putative siRNAs within the overlapping regions tend to target only one transcript of a given NAT pair, which is consistent with our previous finding on salt- and bacteria-induced nat-siRNAs. In addition, we found that genes encoding plastid- or

  5. Interfering with Capitalism's Spell: Peter McLaren's Revolutionary Liminality

    Directory of Open Access Journals (Sweden)

    Samuel Day Fassbinder

    2006-10-01

    Full Text Available McLaren’s recent (post-2000 writings promote a form of agency called “revolutionary critical pedagogy,” and a type of agent, the “committed intellectual” (McLaren 2005b, p. 253-281. But one can find an earlier agent-type in McLaren’s (1986 Schooling as a Ritual Performance, the “liminal servant,” that explains how “critical pedagogy is secured by the most fecund of revolutionary talismans, critique” (2005a: 9. Borrowing from Theodor Adorno (1968, I suggest that McLaren’s recent writing uses aspects of the “liminal servant” for the purpose of interfering with the “spell” of capitalist social relations through “revolutionary critical pedagogy.” The beginning prologue examines “revolutionary liminality” in McLaren’s writing; the second part explains how his written discursive strategies (naming the culprit, suggesting icons, theorizing to unite the disaffected work to act out “revolutionary liminality.”

  6. ROW (Right-of-Way) interfering construction activities management program

    Energy Technology Data Exchange (ETDEWEB)

    Rosito, Roberta; Oliveira, Marisa; Lima, Shirley [TRANSPETRO - PETROBRAS Transporte S.A., Rio de Janeiro, RJ (Brazil)

    2009-07-01

    A significant portion of pipeline failures occurs due to external damage. This includes third party right of way (ROW) encroachment, which shall be identified and avoided. However, injuries caused by known and planned activities do happen. Construction of crossing or sharing ROW pipelines, crossing roads and bridges, neighboring buildings and excavations of any kind might put existing pipelines in risk. This paper presents how the TRANSPETRO ROW Interfering Construction Activities Management Program is implemented by a regional ROW maintenance department responsible for more than 3,000 km of pipelines, mostly in Rio de Janeiro and Minas Gerais states. This program is based on a TRANSPETRO procedure that was written after the publication of the Official Order number 125 of ANP (Oil, Gas and Biofuel Brazilian National Agency). Tasks from design review and approval to field construction supervision are performed by the staff responsible for the routine patrols and maintenance management. The ability of foreseeing risky activities is improved by expertise gained from day-to-day work on site. (author)

  7. Determination of mutually interfering elements in activation analysis

    International Nuclear Information System (INIS)

    Figueiredo, A.M.G.

    1979-01-01

    The determination of the elements present in the groups scandium-zinc, mercury-selenium and arsenic-antimony-bromine represents a classical problem in thermal neutron activation analysis because the gamma-ray peaks of the radioisotopes produced from these elements by activation appear very close in the spectrum. A study is made of the possibility of simultaneous instrumental determination of these elements by means of the spectrum stripping technique, using a 400-channel analyser coupled to a Nal(Tl) detector and a 4096-channel analyser coupled to a Ge(Li) detector. Artificial mixtures of the interfering elements in varying proportions are prepared, so as to reproduce possible real samples, where the elements may be present at several concentrations. Radiochemical separation techniques for the cited elements are studied with the use of tracers. For the separation of scadium and zinc, the technique of extraction chromatography is applied. The separation of mercury and selenium is accomplished by means of ion exchange. The technique of coprecipitation is used to separate bromine from arsenic and antimony followed by ion exchange to isolate these two elements from each other. The precision and the accuracy of the results are discussed. (Author) [pt

  8. Memory interfering effects of chlordiazepoxide on consummatory successive negative contrast.

    Science.gov (United States)

    Ortega, Leonardo A; Glueck, Amanda C; Daniel, Alan M; Prado-Rivera, Mayerli A; White, Michelle M; Papini, Mauricio R

    2014-01-01

    Long-Evans rats downshifted from 32% to 4% sucrose solution exhibit lower consummatory behavior during downshift trials than rats exposed only to 4% sucrose. In Experiment 1, this effect, called consummatory successive negative contrast (cSNC), was attenuated by administration of the benzodiazepine anxiolytic chlordiazepoxide (CDP, 5mg/kg, ip) before the second downshift trial (Trial 12), but was not affected when CDP was administered before the first downshift trial (Trial 11). In Experiment 2, CDP administered after Trial 11 actually enhanced the cSNC effect on Trial 12. This posttrial effect of CDP was reduced by delayed administration (Experiment 3). This CDP effect was not present in the absence of incentive downshift (Experiments 4-5), or when animals were tested with the preshift incentive (Experiment 6) or after complete recovery from cSNC (Experiment 7). The posttrial CDP effect was observed after an 8-day interval between Trials 11 and 12 (Experiment 8) and when administered after Trial 12, rather than Trial 11 (Experiment 9). Experiment 10 extended the effect to Wistar rats. Because CDP is a memory interfering drug, it was hypothesized that its posttrial administration interferes with the consolidation of the memory of the downshifted incentive, thus prolonging the mismatch between expected (32% sucrose) and obtained (4% sucrose) incentives that leads to the cSNC effect. Copyright © 2013 Elsevier Inc. All rights reserved.

  9. Random small interfering RNA library screen identifies siRNAs that induce human erythroleukemia cell differentiation.

    Science.gov (United States)

    Fan, Cuiqing; Xiong, Yuan; Zhu, Ning; Lu, Yabin; Zhang, Jiewen; Wang, Song; Liang, Zicai; Shen, Yan; Chen, Meihong

    2011-03-01

    Cancers are characterized by poor differentiation. Differentiation therapy is a strategy to alleviate malignant phenotypes by inducing cancer cell differentiation. Here we carried out a combinatorial high-throughput screen with a random siRNA library on human erythroleukemia K-562 cell differentiation. Two siRNAs screened from the library were validated to be able to induce erythroid differentiation to varying degrees, determined by CD235 and globin up-regulation, GATA-2 down-regulation, and cell growth inhibition. The screen we performed here is the first trial of screening cancer differentiation-inducing agents from a random siRNA library, demonstrating that a random siRNA library can be considered as a new resource in efforts to seek new therapeutic agents for cancers. As a random siRNA library has a broad coverage for the entire genome, including known/unknown genes and protein coding/non-coding sequences, screening using a random siRNA library can be expected to greatly augment the repertoire of therapeutic siRNAs for cancers.

  10. Inhibition of Reporter Genes by Small Interfering RNAs in Cell Culture and Living Fish

    DEFF Research Database (Denmark)

    Larashati, Sekar; Schyth, Brian Dall; Lorenzen, Niels

    2011-01-01

    embryonic kidney HEK293t cells was used because they are easy to transfect and generally show high expression of transfected genes. Two types of fish including albino trouts were used as animal models to get better visualization of reporter gene expression. The luciferase gene was used as reporter gene...

  11. Dynamic parent-of-origin effects on small interfering RNA expression in the developing maize endosperm

    OpenAIRE

    Xin, Mingming; Yang, Ruolin; Yao, Yingyin; Ma, Chuang; Peng, Huiru; Sun, Qixin; Wang, Xiangfeng; Ni, Zhongfu

    2014-01-01

    Background In angiosperms, the endosperm plays a crucial placenta-like role in that not only is it necessary for nurturing the embryo, but also regulating embryogenesis through complicated genetic and epigenetic interactions with other seed compartments and is the primary tissue in which genomic imprinting occurs. Results We observed a gradual increase of paternal siRNA expression in the early stages of kernels and an expected 2:1 maternal to paternal ratio in 7-DAP endosperm via sequencing o...

  12. A retrotransposon-driven Dicer isoform directs endogenous small interfering RNA production in mouse oocytes

    Czech Academy of Sciences Publication Activity Database

    Flemr, Matyáš; Malík, Radek; Franke, V.; Nejepínská, Jana; Sedláček, Radislav; Vlahovicek, K.; Svoboda, Petr

    2013-01-01

    Roč. 155, č. 4 (2013), s. 807-816 ISSN 0092-8674 R&D Projects: GA ČR GAP305/10/2215; GA ČR(CZ) GBP305/12/G034; GA ČR GA204/09/0085; GA MŠk(CZ) LM2011032; GA MŠk ED1.1.00/02.0109 Grant - others:AV ČR(CZ) M200521202 Institutional support: RVO:68378050 Keywords : Dicer * miRNA * RNAi * mouse oocytes Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 33.116, year: 2013

  13. Efficient delivery of small interfering RNA into injured spinal cords in rats by photomechanical waves

    Science.gov (United States)

    Ando, Takahiro; Sato, Shunichi; Toyooka, Terushige; Kobayashi, Hiroaki; Nawashiro, Hiroshi; Ashida, Hiroshi; Obara, Minoru

    2011-03-01

    In the central nervous system, lack of axonal regeneration leads to permanent functional disabilities. In spinal cord injury (SCI), the over-expressions of intermediate filament (IF) proteins, such as glial fibrillary acidic protein (GFAP) and vimentin, are mainly involved in glial scar formation; these proteins work as both physical and biochemical barriers to axonal regeneration. Thus, silencing of these IF proteins would be an attractive strategy to treat SCI. In this study, we first attempted to deliver fluorescent probe-labeled siRNAs into injured spinal cords in rats by applying photomechanical waves (PMWs) to examine the capability of PMWs as a tool for siRNA delivery. Intense fluorescence from siRNAs was observed in much broader regions in the spinal cords with PMW application when compared with those with siRNA injection alone. Based on this result, we delivered siRNAs for GFAP and vimentin into injured spinal tissues in rats by applying PMWs. The treatment resulted in efficient silencing of the proteins at five days after SCI and a decrease of the cavity area in the injured tissue at three weeks after SCI when compared with those with siRNA injection alone. These results demonstrate the capability of PMWs for efficient delivery of siRNAs into injured spinal cords and treatment of SCIs.

  14. Tumour suppressive function of HUWE1 in thyroid cancer

    Indian Academy of Sciences (India)

    2016-07-14

    Jul 14, 2016 ... Small-interfering RNA mediated knockdown of HUWE1 promoted cell proliferation, cell migration and invasion in thyroid cancer cells. Overexpression of HUWE1 conferred partial sensitivity to chemo drugs interfering with DNA replication in these cells. Moreover, HUWE1 was found to be down-regulated in ...

  15. MicroRNA response to hypoxic stress in soft tissue sarcoma cells: microRNA mediated regulation of HIF3α

    International Nuclear Information System (INIS)

    Gits, Caroline MM; Wiemer, Erik AC; Kuijk, Patricia F van; Rijck, Jonneke CWM de; Muskens, Nikky; Jonkers, Moniek BE; IJcken, Wilfred F van; Mathijssen, Ron HJ; Verweij, Jaap; Sleijfer, Stefan

    2014-01-01

    evidence for the miRNA mediated regulation of HIF3α by hypoxia responsive miRNAs in STS, which may help to tightly regulate and fine-tune the hypoxic response. This provides a better insight into the mechanisms underlying the hypoxic response in STS and may ultimately yield information on novel prognostic and predictive markers or targets for treatment

  16. On the degrees of freedom of interference alignment for multicell MIMO interfering broadcast channels.

    Science.gov (United States)

    Choi, Hyun-Ho

    2014-01-01

    The interference alignment (IA) is a promising technique to efficiently mitigate interference and to enhance capacity of a wireless network. This paper proposes an interference alignment scheme for a cellular network with L cells and K users under a multiple-input multiple-output (MIMO) Gaussian interfering broadcast channel (IFBC) scenario. The proposed IA scheme aligns intercell interferences (ICI) into a small dimensional subspace through a cooperative receive beamforming and cancels both the ICI and interuser interferences (IUI) simultaneously through a transmit beamforming. We characterize the feasibility condition for the proposed IA to achieve a total number of degrees of freedom (DoF) of LK in terms of the numbers of transmit antennas and receive antennas. Then we derive the maximum number of DoF achieved by the proposed IA by finding an optimal dimension of ICI alignment subspace for a given antenna configuration. The numerical results show that the proposed IA scheme has a better DoF performance than the conventional schemes.

  17. Fangchinoline inhibits human immunodeficiency virus type 1 replication by interfering with gp160 proteolytic processing.

    Directory of Open Access Journals (Sweden)

    Zhitao Wan

    Full Text Available The introduction of highly active antiretroviral therapy has led to a significant reduction in the morbidity and mortality of acquired immunodeficiency syndrome patients. However, the emergence of drug resistance has resulted in the failure of treatments in large numbers of patients and thus necessitates the development of new classes of anti-HIV drugs. In this study, more than 200 plant-derived small-molecule compounds were evaluated in a cell-based HIV-1 antiviral screen, resulting in the identification of a novel HIV-1 inhibitor (fangchinoline. Fangchinoline, a bisbenzylisoquinoline alkaloid isolated from Radix Stephaniae tetrandrae, exhibited antiviral activity against HIV-1 laboratory strains NL4-3, LAI and BaL in MT-4 and PM1 cells with a 50% effective concentration ranging from 0.8 to 1.7 µM. Mechanism-of-action studies showed that fangchinoline did not exhibit measurable antiviral activity in TZM-b1 cells but did inhibit the production of infectious virions in HIV-1 cDNA transfected 293T cells, which suggests that the compound targets a late event in infection cycle. Furthermore, the antiviral effect of fangchinoline seems to be HIV-1 envelope-dependent, as the production of infectious HIV-1 particles packaged with a heterologous envelope, the vesicular stomatitis virus G glycoprotein, was unaffected by fangchinoline. Western blot analysis of HIV envelope proteins expressed in transfected 293T cells and in isolated virions showed that fangchinoline inhibited HIV-1 gp160 processing, resulting in reduced envelope glycoprotein incorporation into nascent virions. Collectively, our results demonstrate that fangchinoline inhibits HIV-1 replication by interfering with gp160 proteolytic processing. Fangchinoline may serve as a starting point for developing a new HIV-1 therapeutic approach.

  18. Quantification of analytes affected by relevant interfering signals under quality controlled conditions

    International Nuclear Information System (INIS)

    Bettencourt da Silva, Ricardo J.N.; Santos, Julia R.; Camoes, M. Filomena G.F.C.

    2006-01-01

    The analysis of organic contaminants or residues in biological samples is frequently affected by the presence of compounds producing interfering instrumental signals. This feature is responsible for the higher complexity and cost of these analyses and/or by a significant reduction of the number of studied analytes in a multi-analyte method. This work presents a methodology to estimate the impact of the interfering compounds on the quality of the analysis of complex samples, based on separative instrumental methods of analysis, aiming at supporting the inclusion of analytes affected by interfering compounds in the list of compounds analysed in the studied samples. The proposed methodology involves the study of the magnitude of the signal produced by the interfering compounds in the analysed matrix, and is applicable to analytical systems affected by interfering compounds with varying concentration in the studied matrix. The proposed methodology is based on the comparison of the signals from a representative number of examples of the studied matrix, in order to estimate the impact of the presence of such compounds on the measurement quality. The treatment of the chromatographic signals necessary to collect these data can be easily performed considering algorithms of subtraction of chromatographic signals available in most of the analytical instrumentation software. The subtraction of the interfering compounds signal from the sample signal allows the compensation of the interfering effect irrespective of the relative magnitude of the interfering and analyte signals, supporting the applicability of the same model of the method performance for a broader concentration range. The quantification of the measurement uncertainty was performed using the differential approach, which allows the estimation of the contribution of the presence of the interfering compounds to the quality of the measurement. The proposed methodology was successfully applied to the analysis of

  19. Preparation and electromagnetic waves attenuation performances of infrared-interfering composite smog

    Science.gov (United States)

    Liu, Xiang-cui; Liu, Qing-hai; Dai, Meng-yan; Shi, Wei-dong; Fang, Guo-feng; Zhang, Tong

    2016-10-01

    The infrared-interfering composite smog material is prepared by a heating and agitating device in aqueous solutions and then sprayed into a cloud chamber for six minutes to form smog using gas-water mixing spray system. The attenuation performances of the smog to visible light, 1.06μm laser, 3-5μm infrared and 8-14μm infrared are evaluated, and compared with those of other testing materials. The results show that the sprayed smog have the best attenuation performances and the longest interfering time to visible light, 1.06μm laser, 3-5μm infrared and 8-14μm infrared. Therefore, the infrared-interfering composite smog material in the form of aqueous solution is the new smoke obscurant materials that are environment-friendly and possess broad application prospects in some aspects such as visible light, laser and infrared countermeasures.

  20. Interfície per al control de dispositius domòtics

    OpenAIRE

    Frutos Rodrigo, Jonathan

    2011-01-01

    El principal objectiu d’aquest projecte es realitzar una interfície per a dispositius domòtics que sigui adaptable. Concretament es tracta de determinar les necessitats d’un sector de la població amb problemes de dependència i establir una interfície altament adaptable que es comuniqui amb diferents elements domòtics de la llar per a facilitar i millorar fins el possible les condicions de vida d’aquest sector de ...

  1. Interferência de plantas daninhas no cultivo da melancia Weeds interference periods in watermelon crop

    Directory of Open Access Journals (Sweden)

    Cleber Daniel de G Maciel

    2008-03-01

    Full Text Available A cultura da melancia é uma atividade explorada regionalmente, sendo uma das mais importantes fontes de renda familiar de pequenos municípios do médio Paranapanema, onde mudanças significativas no processo produtivo são atualmente constatadas, passando de mão-de-obra intensiva para uso de tecnologias promissoras, como é o caso do manejo de plantas daninhas. Um experimento foi conduzido no município de Oscar Bressani (SP, em área de produção comercial, com objetivo de estudar a interferência de plantas daninhas, no cultivo da melancia, na safra 2002/2003. O delineamento experimental utilizado foi de blocos ao acaso com dez tratamentos e quatro repetições, representadas por parcelas com área útil de 18 m², contendo quatro plantas de melancia e infestação prevalecente das espécies Sidaspp, Brachiaria humidicola, Commelina benghalensise Portulaca oleracea. A infestação das plantas daninhas foi estimada através de amostragens aleatórias das parcelas utilizando-se quadro vazado de ferro com 0,5 m de lado. Os tratamentos constaram de testemunhas capinadas e sem capina e diferentes épocas de controle da infestação, de forma que a cultura foi mantida na presença ou ausência das plantas daninhas até 7; 14; 28; 56 e 63 dias após a sua emergência (DAE. A ocorrência do período inicial de convivência possível maior que o período final estabeleceu o Período Crítico de Prevenção da Interferência do 9º ao 13º dias (PCPI= 9-13 DAE. A redução média da produtividade em função da interferência das plantas daninhas durante todo o ciclo da melancia foi de 41,4%. As características diâmetro e espessura da casca dos frutos também foram influenciadas pela convivência com a infestação durante todo o ciclo com decréscimos, de 7,9% e 23,3%, respectivamente, em média, ao contrário do comprimento e diâmetro de ramas e do ºBrix da polpa dos frutos, onde não foram constatadas diferenças significativas.Water melon

  2. Validation of Learning Effort Algorithm for Real-Time Non-Interfering Based Diagnostic Technique

    Science.gov (United States)

    Hsu, Pi-Shan; Chang, Te-Jeng

    2011-01-01

    The objective of this research is to validate the algorithm of learning effort which is an indicator of a new real-time and non-interfering based diagnostic technique. IC3 Mentor, the adaptive e-learning platform fulfilling the requirements of intelligent tutor system, was applied to 165 university students. The learning records of the subjects…

  3. Temperature Measurement of a Miniature Ceramic Heater in the Presence of an Extended Interfering Background Radiation Source Using a Multiwavelength Pyrometer

    Science.gov (United States)

    Ng, Daniel

    1999-01-01

    Temperature measurement of small (millimeter size) objects is generally difficult and demanding. Measurement involving ceramic materials using the traditional one- and two-color pyrometer is difficult because of their complex optical properties, such as low emissivity which may vary with both temperature and wavelength. Pyrometry applications in an environment with an interfering radiation source of extended dimension adds extra complexity to the process. We show that the multiwavelength pyrometer successfully measured the temperatures of a millimeter (mm) size ceramic heater under these demanding conditions.

  4. Evasion of short interfering RNA-directed antiviral silencing in Musa acuminata persistently infected with six distinct banana streak pararetroviruses.

    Science.gov (United States)

    Rajeswaran, Rajendran; Seguin, Jonathan; Chabannes, Matthieu; Duroy, Pierre-Olivier; Laboureau, Nathalie; Farinelli, Laurent; Iskra-Caruana, Marie-Line; Pooggin, Mikhail M

    2014-10-01

    Vegetatively propagated crop plants often suffer from infections with persistent RNA and DNA viruses. Such viruses appear to evade the plant defenses that normally restrict viral replication and spread. The major antiviral defense mechanism is based on RNA silencing generating viral short interfering RNAs (siRNAs) that can potentially repress viral genes posttranscriptionally through RNA cleavage and transcriptionally through DNA cytosine methylation. Here we examined the RNA silencing machinery of banana plants persistently infected with six pararetroviruses after many years of vegetative propagation. Using deep sequencing, we reconstructed consensus master genomes of the viruses and characterized virus-derived and endogenous small RNAs. Consistent with the presence of endogenous siRNAs that can potentially establish and maintain DNA methylation, the banana genomic DNA was extensively methylated in both healthy and virus-infected plants. A novel class of abundant 20-nucleotide (nt) endogenous small RNAs with 5'-terminal guanosine was identified. In all virus-infected plants, 21- to 24-nt viral siRNAs accumulated at relatively high levels (up to 22% of the total small RNA population) and covered the entire circular viral DNA genomes in both orientations. The hotspots of 21-nt and 22-nt siRNAs occurred within open reading frame (ORF) I and II and the 5' portion of ORF III, while 24-nt siRNAs were more evenly distributed along the viral genome. Despite the presence of abundant viral siRNAs of different size classes, the viral DNA was largely free of cytosine methylation. Thus, the virus is able to evade siRNA-directed DNA methylation and thereby avoid transcriptional silencing. This evasion of silencing likely contributes to the persistence of pararetroviruses in banana plants. We report that DNA pararetroviruses in Musa acuminata banana plants are able to evade DNA cytosine methylation and transcriptional gene silencing, despite being targeted by the host silencing

  5. 36 CFR 261.3 - Interfering with a Forest officer, volunteer, or human resource program enrollee or giving false...

    Science.gov (United States)

    2010-07-01

    ... officer, volunteer, or human resource program enrollee or giving false report to a Forest officer. 261.3... General Prohibitions § 261.3 Interfering with a Forest officer, volunteer, or human resource program..., intimidating, or intentionally interfering with any Forest officer, volunteer, or human resource program...

  6. Identification and validation of a virus-inducible ta-siRNA-generating ...

    Indian Academy of Sciences (India)

    2016-02-01

    Feb 1, 2016 ... Trans-acting small interfering RNAs (ta-siRNAs) are a class of endogenous small RNA, associated with post- transcriptional gene silencing. Their biogenesis requires an initial microRNA (miRNA)-mediated cleavage of precur- sor RNA. Around 20 different ta-siRNA-producing loci (TASs), whose sequences ...

  7. Joint profiling of miRNAs and mRNAs reveals miRNA mediated gene regulation in the Göttingen minipig obesity model

    DEFF Research Database (Denmark)

    Mentzel, Caroline M. Junker; Alkan, Ferhat; Keinicke, Helle

    2016-01-01

    Obesity and its comorbidities are an increasing challenge for both affected individuals and health care systems, worldwide. In obese individuals, perturbation of expression of both protein-coding genes and microRNAs (miRNA) are seen in obesity-relevant tissues (i.e. adipose tissue, liver and skel......Obesity and its comorbidities are an increasing challenge for both affected individuals and health care systems, worldwide. In obese individuals, perturbation of expression of both protein-coding genes and microRNAs (miRNA) are seen in obesity-relevant tissues (i.e. adipose tissue, liver...... and skeletal muscle). miRNAs are small non-coding RNA molecules which have important regulatory roles in a wide range of biological processes, including obesity. Rodents are widely used animal models for human diseases including obesity. However, not all research is applicable for human health or diseases...... obesity, due to its capacity to develop severe obesity when fed ad libitum. The aim of this study was to identify differentially expressed of protein-coding genes and miRNAs in a Göttingen minipig obesity model. Liver, skeletal muscle and abdominal adipose tissue were sampled from 7 lean and 7 obese...

  8. Alignment characteristic of nematic liquid crystals on orientational patterns realized by interfering laser light

    International Nuclear Information System (INIS)

    Lee, Eun-Kyu; Kim, Jong-Hyun

    2008-01-01

    We have observed the alignment property and switching behaviour of nematic liquid crystals (NLCs) on orientation patterns that were realized on a photo-active alignment layer by using interferring beams of two coherent laser lights. Linearly polarized light orients the liquid crystals in a direction perpendicular to the polarization and the interferring laser light induced a one-dimensional periodic texture following the interference pattern. Using double irradiation, in which the direction of the second irradiation was rotated by 90 0 to the first irradiation, we constructed a quasi-four-fold symmetric orientation pattern. The NLCs exhibited bistability in two average directions of polarization of the laser light, and they stably switched between the two directions by the in-plane electric field. Furthermore, the NLCs indicated the capability of continuous and memorized switching with a changing electric field on the orientation pattern

  9. Factors interfering with the attribute longitudinality in the primary health care: an integrative review

    Directory of Open Access Journals (Sweden)

    Cristiane Cardoso de Paula

    2015-12-01

    Full Text Available Our objective was to assess the evidence available in the literature about factors interfering with the primary health care attribute longitudinality. This is an integrative review, developed in May of 2014, on the following electronic databases: LILACS, PubMed and Scopus. We used the descriptors “primary health care” and “continuity of patient care”. In total, 16 articles were fully assessed. We organized the data in accordance with care aspects longitudinality (structure and performance and we divided the identified factors in accordance with the attribute interference (favoring or disfavoring. The evidence offer aids to compose a global panorama of interfering factors on longitudinality, reinforcing the value of its interpersonal relationships and minimizing gaps in the organization of health services. The prevalence of descriptive studies suggests the need to strengthen the construction of knowledge with studies of higher evidence level.

  10. Facilitatory and interfering effects of neighbourhood density on speech production: Evidence from aphasic errors.

    OpenAIRE

    Laganaro Marina; Chetelat-Mabillard Daphnée; Frauenfelder Ulrich H

    2013-01-01

    In a system where tens of thousands of words are made up of a limited number of phonemes many words are bound to sound alike. This similarity of the words in the lexicon as characterized by phonological neighbourhood density (PhND) has been shown to affect speed and accuracy of word comprehension and production. Whereas there is a consensus about the interfering nature of neighbourhood effects in comprehension the language production literature offers a more contradictory picture with mainly ...

  11. Facilitatory and interfering effects of neighbourhood density on speech production: evidence from aphasic errors.

    Science.gov (United States)

    Laganaro, Marina; Chetelat-Mabillard, Daphnée; Frauenfelder, Ulrich H

    2013-01-01

    In a system where tens of thousands of words are made up of a limited number of phonemes, many words are bound to sound alike. This similarity of the words in the lexicon as characterized by phonological neighbourhood density (PhND) has been shown to affect speed and accuracy of word comprehension and production. Whereas there is a consensus about the interfering nature of neighbourhood effects in comprehension, the language production literature offers a more contradictory picture with mainly facilitatory but also interfering effects reported on word production. Here we report both of these two types of effects in the same study. Multiple regression mixed models analyses were conducted on PhND effects on errors produced in a naming task by a group of 21 participants with aphasia. These participants produced more formal errors (interfering effect) for words in dense phonological neighbourhoods, but produced fewer nonwords and semantic errors (a facilitatory effect) with increasing density. In order to investigate the nature of these opposite effects of PhND, we further analysed a subset of formal errors and nonword errors by distinguishing errors differing on a single phoneme from the target (corresponding to the definition of phonological neighbours) from those differing on two or more phonemes. This analysis confirmed that only formal errors that were phonological neighbours of the target increased in dense neighbourhoods, while all other errors decreased. Based on additional observations favouring a lexical origin of these formal errors (they exceeded the probability of producing a real-word error by chance, were of a higher frequency, and preserved the grammatical category of the targets), we suggest that the interfering effect of PhND is due to competition between lexical neighbours and target words in dense neighbourhoods.

  12. L1 INTERFERING AND L2 DEVELOPMENTAL WRITING ERRORS AMONG IRANIAN EFL LEARNERS

    OpenAIRE

    Hooshang Khoshsima; Hassan Banaruee

    2017-01-01

    This study aimed to investigate common writing errors among Persian EFL Learners. The focus of the study was to identify Persian interfering and developmental errors based on the four rubrics of sentence styles, mechanics, grammar and punctuations. To achieve this, 80 students and 3 teachers from Iran Language Institute were asked to participate in this study. The instruments for data collection were a proficiency test to test the level of their homogeneity, as well as a written test in which...

  13. MicroRNA-Mediated Positive Feedback Loop and Optimized Bistable Switch in a Cancer Network Involving miR-17-92

    Science.gov (United States)

    Li, Yichen; Li, Yumin; Zhang, Hui; Chen, Yong

    2011-01-01

    MicroRNAs (miRNAs) are small, noncoding RNAs that play an important role in many key biological processes, including development, cell differentiation, the cell cycle and apoptosis, as central post-transcriptional regulators of gene expression. Recent studies have shown that miRNAs can act as oncogenes and tumor suppressors depending on the context. The present work focuses on the physiological significance of miRNAs and their role in regulating the switching behavior. We illustrate an abstract model of the Myc/E2F/miR-17-92 network presented by Aguda et al. (2008), which is composed of coupling between the E2F/Myc positive feedback loops and the E2F/Myc/miR-17-92 negative feedback loop. By systematically analyzing the network in close association with plausible experimental parameters, we show that, in the presence of miRNAs, the system bistability emerges from the system, with a bistable switch and a one-way switch presented by Aguda et al. instead of a single one-way switch. Moreover, the miRNAs can optimize the switching process. The model produces a diverse array of response-signal behaviors in response to various potential regulating scenarios. The model predicts that this transition exists, one from cell death or the cancerous phenotype directly to cell quiescence, due to the existence of miRNAs. It was also found that the network involving miR-17-92 exhibits high noise sensitivity due to a positive feedback loop and also maintains resistance to noise from a negative feedback loop. PMID:22022595

  14. Determination of NH4+ in Environmental Water with Interfering Substances Using the Modified Nessler Method

    Directory of Open Access Journals (Sweden)

    Heonsang Jeong

    2013-01-01

    Full Text Available Nitrogen is an essential element in the environment. If excess nitrogen including NH4 + is present in water, however, it can result in algae blooming and eventually the destruction of the aquatic ecosystem. Therefore, the determination of NH4 + in streams, lakes, and effluents of the treatment facilities has long been carried out. The Nessler method is the most common spectrophotometric method to measure NH4 + in water. However, the result of the method becomes inaccurate if there are interfering substances such as Cl2, Cl−, hardness-causing compounds (e.g., Mg2+, and Fe2+ in target water samples. In this study, therefore, the traditional Nessler method has been modified to eliminate the effects of interfering substances; the so-called MS was added to water samples. In addition, the polyvinyl alcohol reagent as a dispersing agent was added to water samples to increase the sensitivity and reproducibility of the method. The modified method could successfully analyze NH4 + of water samples even with the interfering substance at high concentration.

  15. Thiophenone Attenuates Enteropathogenic Escherichia coli O103:H2 Virulence by Interfering with AI-2 Signaling.

    Science.gov (United States)

    Witsø, Ingun Lund; Valen Rukke, Håkon; Benneche, Tore; Aamdal Scheie, Anne

    2016-01-01

    Interference with bacterial quorum sensing communication provides an anti-virulence strategy to control pathogenic bacteria. Here, using the Enteropathogenic E. coli (EPEC) O103:H2, we showed for the first time that thiophenone TF101 reduced expression of lsrB; the gene encoding the AI-2 receptor. Combined results of transcriptional and phenotypic analyses suggested that TF101 interfere with AI-2 signalling, possibly by competing with AI-2 for binding to LsrB. This is supported by in silico docking prediction of thiophenone TF101 in the LsrB pocket. Transcriptional analyses furthermore showed that thiophenone TF101 interfered with expression of the virulence genes eae and fimH. In addition, TF101 reduced AI-2 induced E. coli adhesion to colorectal adenocarcinoma cells. TF101, on the other hand, did not affect epinephrine or norepinephrine enhanced E. coli adhesion. Overall, our results showed that thiophenone TF101 interfered with virulence expression in E. coli O103:H2, suggestedly by interfering with AI-2 mediated quorum sensing. We thus conclude that thiophenone TF101 might represent a promising future anti-virulence agent in the fight against pathogenic E. coli.

  16. Thiophenone Attenuates Enteropathogenic Escherichia coli O103:H2 Virulence by Interfering with AI-2 Signaling

    Science.gov (United States)

    Valen Rukke, Håkon; Benneche, Tore; Aamdal Scheie, Anne

    2016-01-01

    Interference with bacterial quorum sensing communication provides an anti-virulence strategy to control pathogenic bacteria. Here, using the Enteropathogenic E. coli (EPEC) O103:H2, we showed for the first time that thiophenone TF101 reduced expression of lsrB; the gene encoding the AI-2 receptor. Combined results of transcriptional and phenotypic analyses suggested that TF101 interfere with AI-2 signalling, possibly by competing with AI-2 for binding to LsrB. This is supported by in silico docking prediction of thiophenone TF101 in the LsrB pocket. Transcriptional analyses furthermore showed that thiophenone TF101 interfered with expression of the virulence genes eae and fimH. In addition, TF101 reduced AI-2 induced E. coli adhesion to colorectal adenocarcinoma cells. TF101, on the other hand, did not affect epinephrine or norepinephrine enhanced E. coli adhesion. Overall, our results showed that thiophenone TF101 interfered with virulence expression in E. coli O103:H2, suggestedly by interfering with AI-2 mediated quorum sensing. We thus conclude that thiophenone TF101 might represent a promising future anti-virulence agent in the fight against pathogenic E. coli. PMID:27309855

  17. Controlling interfered area in interferential current stimulation by electrode-area patterning.

    Science.gov (United States)

    Bounyong, S; Adachi, S; Yoshimoto, T; Ota, T; Ozawa, J

    2016-08-01

    Interferential current therapy is a noninvasive therapy using simultaneously two or more medium-frequency currents passing through tissue. By controlling the interfered area of the current flows, selective stimulation is possible in target muscles, including deep muscles. However, controlling the interfered area or the intensity of the current precisely is still lacking. Using simulations based on a biological model of the thigh as well as electrical muscle stimulation (EMS) experiments, we investigated the influence of electrode area ratio in changing the interfered area of the currents. Simulation and experiments were conducted under the same conditions, whereby current signals were applied through electrodes placed on the quadriceps and hamstring with an electrode area ratio of either 1:1 or 3:1. A comparison of the simulation results showed that the interferential current density decreased near the larger area electrode but increased near the smaller area electrode. In addition, the EMS experiment also showed that the quadriceps were stimulated using electrodes in a 1:1 area ratio, and the hamstrings were stimulated using electrodes in a 3:1 area ratio. These results demonstrated the possibility of controlling the area application of interferential current through electrode area patterning.

  18. MicroRNA-Mediated Down-Regulation of Apoptosis Signal-Regulating Kinase 1 (ASK1 Attenuates the Apoptosis of Human Mesenchymal Stem Cells (MSCs Transplanted into Infarcted Heart

    Directory of Open Access Journals (Sweden)

    Chang Youn Lee

    2016-10-01

    Full Text Available Stem cell therapy using adult stem cells, such as mesenchymal stem cells (MSCs has produced some promising results in treating the damaged heart. However, the low survival rate of MSCs after transplantation is still one of the crucial factors that limit the therapeutic effect of stem cells. In the damaged heart, oxidative stress due to reactive oxygen species (ROS production can cause the death of transplanted MSCs. Apoptosis signal-regulating kinase 1 (ASK1 has been implicated in the development of oxidative stress-related pathologic conditions. Thus, we hypothesized that down-regulation of ASK1 in human MSCs (hMSCs might attenuate the post-transplantation death of MSCs. To test this hypothesis, we screened microRNAs (miRNAs based on a miRNA-target prediction database and empirical data and investigated the anti-apoptotic effect of selected miRNAs on human adipose-derived stem cells (hASCs and on rat myocardial infarction (MI models. Our data indicated that miRNA-301a most significantly suppressed ASK1 expression in hASCs. Apoptosis-related genes were significantly down-regulated in miRNA-301a-enriched hASCs exposed to hypoxic conditions. Taken together, these data show that miRNA-mediated down-regulation of ASK1 protects MSCs during post-transplantation, leading to an increase in the efficacy of MSC-based cell therapy.

  19. An in vitro screening assay based on synthetic prion protein peptides for identification of fibril-interfering compounds

    NARCIS (Netherlands)

    Boshuizen, R.S.; Langeveld, J.P.M.; Salmona, M.; Williams, A.; Meloen, R.H.; Langendijk, J.P.

    2004-01-01

    Transmissible spongiform encephalopathies are neurodegenerative diseases and are considered to be caused by malformed prion proteins accumulated into fibrillar structures that can then aggregate to form larger deposits or amyloid plaques. The identification of fibril-interfering compounds is of

  20. Effects of small interfering RNA targeting thymidylate synthase on survival of ACC3 cells from salivary adenoid cystic carcinoma

    International Nuclear Information System (INIS)

    Shirasaki, Takashi; Maruya, Shin-ichiro; Mizukami, Hiroki; Kakehata, Seiji; Kurotaki, Hidekachi; Yagihashi, Soroku; Shinkawa, Hideichi

    2008-01-01

    Thymidylate synthase (TS) is an important target for chemotherapeutic treatment of cancer and high expression of TS has been associated with poor prognosis or refractory disease in several cancers including colorectal and head and neck cancer. Although TS is known to regulate cell cycles and transcription factors, its potency as a therapeutic target has not been fully explored in adenoid cystic carcinoma (ACC). An ACC cell line (ACC3) was transfected with siRNA targeting the TS gene and inhibition of cell growth and induction of apoptosis-associated molecules were evaluated in vitro. In addition, the in vivo effect of TS siRNA on tumor progression was assessed using a xenograft model. Our results demonstrated that ACC3 cells showed significantly higher TS expression than non-cancer cell lines and the induction of TS siRNA led to inhibition of cell proliferation. The effect was associated with an increase in p53, p21, and active caspase-3 and S-phase accumulation. We also found up-regulation of spermidine/spermine N1-acetyltransferase (SSAT), a polyamine metabolic enzyme. Furthermore, treatment with TS siRNA delivered by atelocollagen showed a significant cytostatic effect through the induction of apoptosis in a xenograft model. TS may be an important therapeutic target and siRNA targeting TS may be of potential therapeutic value in ACC

  1. Small interfering RNA targeting ILK inhibits metastasis in human tongue cancer cells through repression of epithelial-to-mesenchymal transition

    Energy Technology Data Exchange (ETDEWEB)

    Xing, Yu [College of Laboratory Medicine, Chongqing Medical University, Chongqing (China); Laboratory of Forensic Medicine and Biomedical Information, Chongqing Medical University, Chongqing (China); Qi, Jin [The Affiliated Hospital of Stomatology, Chongqing Medical University (China); Deng, Shixiong [College of Laboratory Medicine, Chongqing Medical University, Chongqing (China); Laboratory of Forensic Medicine and Biomedical Information, Chongqing Medical University, Chongqing (China); Wang, Cheng [Molecular Medicine and Cancer Research Center, Chongqing Medical University, Chongqing (China); Department of Cell Biology and Genetics, Chongqing Medical University, Chongqing (China); Zhang, Luyu [Molecular Medicine and Cancer Research Center, Chongqing Medical University, Chongqing (China); Chen, Junxia, E-mail: chjunxia@126.com [Molecular Medicine and Cancer Research Center, Chongqing Medical University, Chongqing (China); Department of Cell Biology and Genetics, Chongqing Medical University, Chongqing (China)

    2013-08-01

    Integrin-linked kinase (ILK) is a multifunctional serine/threonine kinase. Accumulating evidences suggest that ILK are involved in cell–matrix interactions, cell proliferation, invasion, migration, angiogenesis and Epithelial–mesenchymal transition (EMT). However, the underlying mechanisms remain largely unknown. EMT has been postulated as a prerequisite for metastasis. The reports have demonstrated that EMT was implicated in metastasis of oral squamous cell carcinomas. Therefore, here we further postulate that ILK might participate in EMT of tongue cancer. We showed that ILK siRNA inhibited EMT with low N-cadherin, Vimentin, Snail, Slug and Twist as well as high E-cadherin expression in vivo and in vitro. We found that knockdown of ILK inhibited cell proliferation, migration and invasion as well as changed cell morphology. We also demonstrated that ILK siRNA inhibited phosphorylation of downstream signaling targets Akt and GSK3β as well as reduced expression of MMP2 and MMP9. Furthermore, we found that the tongue tumor with high metastasis capability showed higher ILK, Vimentin, Snail, Slug and Twist as well as lower E-cadherin expression in clinical specimens. Finally, ILK siRNA led to the suppression for tumorigenesis and metastasis in vivo. Our findings suggest that ILK could be a novel diagnostic and therapeutic target for tongue cancer. Highlights: • ILK siRNA influences cell morphology, cell cycle, migration and invasion. • ILK siRNA affects the expression of proteins associated with EMT. • ILK expression is related to EMT in clinical human tongue tumors. • ILK siRNA inhibits metastasis of the tongue cancer cells through suppressing EMT.

  2. Peptidomimetics with beta-peptoid resudies as carriers for intracellular delivery of small interfering RNA (siRNA)

    DEFF Research Database (Denmark)

    Foged, Camilla

    Intracellular delivery using cell penetrating peptides is a promising approach for the transport of biomacromolecules and particulate carriers across cell membranes into cells to modify cellular functions. Synthetic peptides with novel backbone design were examined for their ability to form...... prepared by mixing and characterized with respect to size and surface charge. At ratios of peptide nitrogen to siRNA phosphate (N/P) of 1 and below, particles with narrow size distributions (poly dispersity indexes lower than 0.11) ranging from approximately 100 to 350 nm were formed, and they showed...... a negative zeta potential (-24 to -31 mV). At higher N/P ratios, larger aggregates with zeta potential close to neutral were formed. However, the complexes were not able to silence the expression of enhanced green fluorescent protein (EGFP) in HeLa-cells stably expressing EGFP, which was measured by flow...

  3. Small interfering RNA (siRNA) against Slug induces apoptosis and sensitizes human anaplastic thyroid carcinoma cells to doxorubicin.

    Science.gov (United States)

    Pan, Yinghua; Liu, Peiji; Chen, Deng; Dou, Linying

    2017-01-01

    Anaplastic thyroid carcinoma (ATC) is one of the most aggressive human cancers and often shows resistance to multimodal therapeutic approaches. It has been shown that the transcriptional repressor Slug inhibits the chemotherapeutic agent-induced apoptosis of cancer cells. We evaluated whether targeting of Slug could augment doxorubicin (DOX)-induced apoptosis of ATC cells. We also determined changes in PUMA (p53-upregulated modulator of apoptosis) expression levels to identify possible mechanisms of their combined actions. SW1736 cells were transfected with Slug siRNA or/and PUMA siRNA and then exposed to DOX (0.1, 1, and 5 μ M) for selected times. Scrambled siRNA was used as a control. The effects on cell viability were determined via MTT assay. Apoptosis was assessed using TUNEL assays and annexin V staining, and was confirmed by flow cytometry analyses. Slug and PUMA levels were determined using western blotting, RT-PCR and immunofluorescence analyses. We used a subcutaneous implanted tumor model of SW1736 cells in nude mice to assess the effects of Slug silencing in combination with DOX on tumor development. Apoptosis was assessed via TUNEL assay. Targeting of Slug using siRNA inhibits growth of SW1736 cells and sensitizes SW1736 cells to DOX in vitro and vivo. Targeting of Slug combined with DOX led to lower cell viability than treatment with DOX alone in SW1736 cells. TUNEL and flow cytometry analyses showed that targeting of Slug enhanced DOX-induced apoptosis of SW1736 cells. In addition, targeting of Slug increased PUMA expression, and targeting of PUMA restored the chemoresistance of SW1736/Slug siRNA cells to DOX. Knockdown of Slug enhanced the antitumor activity of DOX in SW1736 cells via induction of PUMA upregulation. Our results suggest that targeting of Slug has good potential for the development of new therapeutic strategies for ATC.

  4. Enhancement of Gene Silencing Effect and Membrane Permeability by Peptide-Conjugated 27-Nucleotide Small Interfering RNA

    Directory of Open Access Journals (Sweden)

    Toshio Seyama

    2012-09-01

    Full Text Available Two different sizes of siRNAs, of which one type was 21-nucleotide (nt siRNA containing 2-nt dangling ends and the other type was 27-nt siRNA with blunt ends, were conjugated with a nuclear export signal peptide of HIV-1 Rev at the 5′-sense end. Processing by Dicer enzyme, cell membrane permeability, and RNAi efficiency of the peptide-conjugated siRNAs were examined. Dicer cleaved the peptide-conjugated 27-nt siRNA leading to the release of 21-nt siRNA, whereas the peptide-conjugated 21-nt siRNA was not cleaved. High membrane permeability and cytoplasmic localization was found in the conjugates. Moreover, the peptide-conjugated 27-nt siRNA showed increased potency of RNAi in comparison with the nonmodified 21-nt and 27-nt siRNAs, whereas the peptide-conjugated 21-nt siRNA showed decreased RNAi efficacy. This potent RNAi efficacy is probably owing to acceleration of RISC through recognition by Dicer, as well as to the improvement of cell membrane permeability and intracellular accumulation.

  5. Real-Time Perceptual Model for Distraction in Interfering Audio-on-Audio Scenarios

    DEFF Research Database (Denmark)

    Rämö, Jussi; Bech, Søren; Jensen, Søren Holdt

    2017-01-01

    model. Thus, while providing similar accuracy as the previous model, the proposed model can be run in real time. The proposed distraction model can be used as a tool for evaluating and optimizing sound-zone systems. Furthermore, the real-time capability of the model introduces new possibilities......This letter proposes a real-time perceptual model predicting the experienced distraction occurring in interfering audio-on-audio situations. The proposed model improves the computational efficiency of a previous distraction model, which cannot provide predictions in real time. The chosen approach...

  6. Genie Tree and Degrees of Freedom of the Symmetric MIMO Interfering Broadcast Channel

    OpenAIRE

    Liu, Tingting; Yang, Chenyang

    2013-01-01

    In this paper, we study the information theoretic maximal degrees of freedom (DoF) for the symmetric multi-input-multi-output (MIMO) interfering broadcast channel (IBC) with arbitrary antenna configurations. For the G-cell K-user MXN MIMO-IBC network, we find that the information theoretic maximal DoF per user are related to three DoF bounds: 1) the decomposition DoF bound d^{Decom}=MN/(M+KN), a lower-bound of linear interference alignment (IA) with infinite time/frequency extensions (called ...

  7. Heterophilic antibodies interfering with radioimmunoassay. A false-positive pregnancy test

    Energy Technology Data Exchange (ETDEWEB)

    Vladutiu, A.O.; Sulewski, J.M.; Pudlak, K.A.; Stull, C.G.

    1982-11-19

    A young woman with amenorrhea had a consistently positive pregnancy test result (serum radioimmunoassay measurement of ..beta..-human chorionic gonadotropin hormone). No fetal or placental tissue was found after uterine curettage and exploratory laparotomy. The false-positive pregnancy test result was due to heterophilic antibovine and antigoat antibodies in the patient's serum. These antibodies interfered with radioimmunoassays using goat antibodies. This case shows that serum heterophilic antibodies can interfere with immunoassays and result in unnecessary diagnostic procedures and/or unnecessary treatment.

  8. Heterophilic antibodies interfering with radioimmunoassay. A false-positive pregnancy test

    International Nuclear Information System (INIS)

    Vladutiu, A.O.; Sulewski, J.M.; Pudlak, K.A.; Stull, C.G.

    1982-01-01

    A young woman with amenorrhea had a consistently positive pregnancy test result (serum radioimmunoassay measurement of #betta#-human chorionic gonadotropin hormone). No fetal or placental tissue was found after uterine curettage and exploratory laparotomy. The false-positive pregnancy test result was due to heterophilic antibovine and antigoat antibodies in the patient's serum. These antibodies interfered with radioimmunoassays using goat antibodies. This case shows that serum heterophilic antibodies can interfere with immunoassays and result in unnecessary diagnostic procedures and/or unnecessary treatment

  9. Spectroscopic quantification of extremely rare molecular species in the presence of interfering optical absorption

    Science.gov (United States)

    Ognibene, Ted; Bench, Graham; McCartt, Alan Daniel; Turteltaub, Kenneth; Rella, Chris W.; Tan, Sze; Hoffnagle, John A.; Crosson, Eric

    2017-05-09

    Optical spectrometer apparatus, systems, and methods for analysis of carbon-14 including a resonant optical cavity configured to accept a sample gas including carbon-14, an optical source configured to deliver optical radiation to the resonant optical cavity, an optical detector configured to detect optical radiation emitted from the resonant cavity and to provide a detector signal; and a processor configured to compute a carbon-14 concentration from the detector signal, wherein computing the carbon-14 concentration from the detector signal includes fitting a spectroscopic model to a measured spectrogram, wherein the spectroscopic model accounts for contributions from one or more interfering species that spectroscopically interfere with carbon-14.

  10. Neutralization Interfering Antibodies: A “Novel” Example of Humoral Immune Dysfunction Facilitating Viral Escape?

    Directory of Open Access Journals (Sweden)

    Roberto Burioni

    2012-09-01

    Full Text Available The immune response against some viral pathogens, in particular those causing chronic infections, is often ineffective notwithstanding a robust humoral neutralizing response. Several evasion mechanisms capable of subverting the activity of neutralizing antibodies (nAbs have been described. Among them, the elicitation of non-neutralizing and interfering Abs has been hypothesized. Recently, this evasion mechanism has acquired an increasing interest given its possible impact on novel nAb-based antiviral therapeutic and prophylactic approaches. In this review, we illustrate the mechanisms of Ab-mediated interference and the viral pathogens described in literature as able to adopt this “novel” evasion strategy.

  11. Neutralization Interfering Antibodies: A “Novel” Example of Humoral Immune Dysfunction Facilitating Viral Escape?

    Science.gov (United States)

    Nicasio, Mancini; Sautto, Giuseppe; Clementi, Nicola; Diotti, Roberta A.; Criscuolo, Elena; Castelli, Matteo; Solforosi, Laura; Clementi, Massimo; Burioni, Roberto

    2012-01-01

    The immune response against some viral pathogens, in particular those causing chronic infections, is often ineffective notwithstanding a robust humoral neutralizing response. Several evasion mechanisms capable of subverting the activity of neutralizing antibodies (nAbs) have been described. Among them, the elicitation of non-neutralizing and interfering Abs has been hypothesized. Recently, this evasion mechanism has acquired an increasing interest given its possible impact on novel nAb-based antiviral therapeutic and prophylactic approaches. In this review, we illustrate the mechanisms of Ab-mediated interference and the viral pathogens described in literature as able to adopt this “novel” evasion strategy. PMID:23170181

  12. Neutralization interfering antibodies: a "novel" example of humoral immune dysfunction facilitating viral escape?

    Science.gov (United States)

    Nicasio, Mancini; Sautto, Giuseppe; Clementi, Nicola; Diotti, Roberta A; Criscuolo, Elena; Castelli, Matteo; Solforosi, Laura; Clementi, Massimo; Burioni, Roberto

    2012-09-01

    The immune response against some viral pathogens, in particular those causing chronic infections, is often ineffective notwithstanding a robust humoral neutralizing response. Several evasion mechanisms capable of subverting the activity of neutralizing antibodies (nAbs) have been described. Among them, the elicitation of non-neutralizing and interfering Abs has been hypothesized. Recently, this evasion mechanism has acquired an increasing interest given its possible impact on novel nAb-based antiviral therapeutic and prophylactic approaches. In this review, we illustrate the mechanisms of Ab-mediated interference and the viral pathogens described in literature as able to adopt this "novel" evasion strategy.

  13. Journal of Biosciences | Indian Academy of Sciences

    Indian Academy of Sciences (India)

    ... functional assays, including cell proliferation, scratch wound healing andinvasion assays. Xenograft experiment was performed to examine in vivo tumour suppressive properties of HUWE1.Small-interfering RNA mediated knockdown of HUWE1 promoted cell proliferation, cell migration and invasion inthyroid cancer cells.

  14. A novel approach for inhibition of HIV-1 by RNA interference: counteracting viral escape with a second generation of siRNAs

    NARCIS (Netherlands)

    ter Brake, Olivier; Berkhout, Ben

    2005-01-01

    RNA interference (RNAi) is an evolutionary conserved gene silencing mechanism in which small interfering RNA (siRNA) mediates the sequence specific degradation of mRNA. The recent discovery that exogenously delivered siRNA can trigger RNAi in mammalian cells raises the possibility to use this

  15. Small Silencing RNAs: Piecing Together a Viral Genome.

    NARCIS (Netherlands)

    Mierlo, J.T. van; Cleef, K.W.R. van; Rij, R.P. van

    2010-01-01

    Virus-derived small interfering RNAs (siRNAs) are the hallmark of RNAi-based antiviral immunity. Wu and colleagues demonstrate how viral genomes can be assembled from these small RNA sequences. Their results provide an approach for virus discovery as well as important insights into how these siRNAs

  16. [Pulse oximetry in the air rescue service. 1: Quantitative detection of interfering factors on the method].

    Science.gov (United States)

    Helm, M; Forstner, K; Lampl, L; Bock, K H

    1993-04-01

    The introduction of pulse oximetric monitoring in prehospital emergency medicine considerably contributed to emergency patients' safety, stability and protection. As inherent in any method of measurement, certain factors can interfere with it and limit its practical application. The emergency helicopter service at Ulm, in a prospective study involving 400 patients, systematically collected data on these limiting factors and evaluated them. The index "S" was established to quantify the time lost due to malfunctioning. Within the study group, the index average was S = 0.269, that is 26.9% of measurement time was subject to interference. The major cause was motion artifacts (68%) sensor probe dislocation (15%), low perfusion (14%) and radiation (3%). Regarding the volume of time lost due to specific interfering factors, motion artifacts (61.8%) and low perfusion (25.5%) were dominant, followed by sensor probe dislocation (10.3%) and radiation (2.4%). Interference therefore, both in time and frequency was primarily due to motion artifacts and low perfusion. The conclusions from this study led to the evaluation of two methods by which the interfering factors could be reduced: 1. ECG-synchronisation of the pulse oximetric signal; 2. The use of adhesive sensors.--The degree of increase in pulse oximetric measurement stability achieved by these two methods will be investigated in part 2 of this study.

  17. An investigation into failure analysis of interfering part of a steam turbine journal bearing

    Directory of Open Access Journals (Sweden)

    M. Mehdizadeh

    2014-10-01

    Full Text Available Journal bearings as so sensitive parts of steam turbines are very susceptible to failure through different mechanisms of wear, fatigue and crush during service conditions. Failure occurring through these mechanisms lead to turbine completely shut down as a result of interfering in working conditions of bearing different parts. In this research, failed interfered part of a journal bearing related to a 320,000 kW steam turbine was examined. Failure analysis investigations were performed by utilizing of stereographic, optical microscopy, scanning electron microscopy (SEM, energy-dispersive X-ray spectroscopy (EDS analysis and hardness test. Surface crush, large amounts of surface cracks, no noticeable changes of failed surface chemical composition and microstructure with significant hardness improvement were the main obtained results. The studies were revealed that the bearing part loosing and inappropriate clearance can produce relative displacements under cyclic gradient loading. This condition was detrimental for the service life of turbine journal bearing via failure through fretting fatigue mechanism.

  18. Mesure par interférométrie laser du mouvement d'une particule proche d'une paroi

    Science.gov (United States)

    Assou, Y.; Joyeux, D.; Azouni, A.; Feuillebois, F.

    1991-02-01

    An experimental technique based on laser interferometry is used to obtain the displacement of a sphere towards a plane wall in a viscous fluid : it consists in inserting the sphere in an interferometric system, in such a way that the displacement of the sphere changes the state of interference. An important feature of the setup is that the shape, the roughness, and the positioning of the sphere in the optical path are relatively uncritical. The spheres used in the experiment are bearing balls, 4 and 5 × 10^{-3} m in diameter. The accuracy on the sphere displacement is of the order of 2 × 10^{-8} m. The interference signal is digitalized and stored in a microcomputer. The data are then processed to yield the friction coefficient f^T_zz of the sphere in its motion very close to the wall. The variation of f^T_zz with the non-dimensional gap \\varepsilon (ratio of the gap to the sphere radius) show three regions: (i) One in which a is small but at least 10 times larger than the non-dimensional rugosity (ratio of the scale of rugosity to the sphere radius) ; there is then a very good agreement with the result valid for a smooth sphere f^T_zz = 1/\\varepsilon from lubrication theory. (ii) When \\varepsilon decreases to the order of the non-dimensional rugosity, the friction coefficient is then smaller than 1/\\varepsilon. The technique thus opens a way to study the effects of rugosity in hydrodynamics. (iii) The technique allows to measure gaps of the order of 10^{-8} m and could thus be used in future studies of short ranges forces. On utilise une technique expérimentale basée sur l'interférométrie laser pour déterminer le déplacement d'une sphère s'approchant d'une paroi plane dans un fluide visqueux: la technique consiste à insérer la sphère dans un système interférométrique, de façon que son déplacement change l'état d'interférence détecté. Une particularité importante du montage utilisé est que la forme, l'état de surface, le positionnement

  19. Which Depressive Symptoms and Medication Side Effects Are Perceived by Patients as Interfering Most with Occupational Functioning?

    Directory of Open Access Journals (Sweden)

    Raymond W. Lam

    2012-01-01

    Full Text Available Background. Major depressive disorder (MDD is associated with significant impairment in occupational functioning. This study sought to determine which depressive symptoms and medication side effects were perceived by patients with MDD to have the greatest interference on work functioning. Methods. 164 consecutive patients with MDD by DSM-IV criteria completed a standard assessment that included a self-rated questionnaire about the degree to which symptoms and side effects interfered with work functioning. Results. The symptoms perceived by patients as interfering most with work functioning were fatigue and low energy, insomnia, concentration and memory problems, anxiety, and irritability. The medication side effects rated as interfering most with work functioning were daytime sedation, insomnia, headache, and agitation/anxiety. There were no differences between men and women in symptoms or side effects that were perceived as interfering with work functioning. Limitations. This was a cross-sectional study; only subjective assessments of work functioning were obtained; the fact that patients were using varied medications acts as a potential confound. Conclusions. Specific depressive symptoms and medication side effects were perceived by patients as interfering more with occupational functioning than others. These factors should be considered in treatment selection (e.g., in the choice of antidepressant in working patients with MDD.

  20. Elimination of eight interfering radioisotopes in the determination of uranium by activation analysis with epithermic neutrons

    International Nuclear Information System (INIS)

    Requejo, C.S.

    1977-01-01

    The total or parcial elimination interfering radioisotopes in activation analysis of uranium by epithermic neutrons, has been made. It was possible to determine uranium, after chemical separation, from samples of organic and mineral matrixes, which had mercury, selenium, bromine, antimony, gold, barium, molybden and tungsten. Mineral samples were analysed giving results between 0.2 to 5.0 ppm of uranium. The same mineral were ground in agate mortar and in tungsten carbide mill. In the first sample is has been found 0.2277 +- -+ 0.0474 ppm U. The second which had tungsten, at level of 150 ppm, after radiochemical separation, it has been found 0.2465+- -+0.0326 ppm U. These results are considered statistically the same [pt

  1. LABORATORY EVALUATION OF ANDALIN, AN INSECT GROWTH REGULATOR INTERFERING WITH CUTICLE DEPOSITION, AGAINST MOSQUITO LARVAE

    Directory of Open Access Journals (Sweden)

    N REHIMI

    2002-12-01

    Full Text Available Andalin, a benzoylphenylurea (BPU derivative, was evaluated on Culex pipiens L. (Diptera: Culicidae. Treatment was made on newly 3rd- and 4th instar larvae for 24 h. The compound exhibited insecticidal activity and mortality occured after earlier inhibition of their development or by their inability to complete their ecdysis. Treatment resulted in a significant larvicidal effect and in a inhibition of adult emergence. Moreover, the compound disturbed growth and development since several morphological types and an increase in the duration of larval stage were observed. Histological study conducted on 4th instar larval integument, showed that Andalin caused a significant reduction in the thickness of cuticles secreted compared to controls. Thus, Andalin prevent molting in C. pipiens by interfering with cuticle deposition confirming the primary mode of action of this BPU insecticide.

  2. Che-1 affects cell growth by interfering with the recruitment of HDAC1 by Rb.

    Science.gov (United States)

    Bruno, Tiziana; De Angelis, Roberta; De Nicola, Francesca; Barbato, Christian; Di Padova, Monica; Corbi, Nicoletta; Libri, Valentina; Benassi, Barbara; Mattei, Elisabetta; Chersi, Alberto; Soddu, Silvia; Floridi, Aristide; Passananti, Claudio; Fanciulli, Maurizio

    2002-11-01

    DNA tumor virus oncoproteins bind and inactivate Rb by interfering with the Rb/HDAC1 interaction. Che-1 is a recently identified human Rb binding protein that inhibits the Rb growth suppressing function. Here we show that Che-1 contacts the Rb pocket region and competes with HDAC1 for Rb binding site, removing HDAC1 from the Rb/E2F complex in vitro and from the E2F target promoters in vivo. Che-1 overexpression activates DNA synthesis in quiescent NIH-3T3 cells through HDAC1 displacement. Consistently, Che-1-specific RNA interference affects E2F activity and cell proliferation in human fibroblasts but not in the pocket protein-defective 293 cells. These findings indicate the existence of a pathway of Rb regulation supporting Che-1 as the cellular counterpart of DNA tumor virus oncoproteins.

  3. Interfering Effect of Black Tea Consumption on Diagnosis of Pancreatic Cancer by CA 19-9.

    Science.gov (United States)

    Al-Janabi, Ali Abdul Hussein S; Tawfeeq, Ekhlas F

    2017-06-01

    The study aims to determine the possible effects of black tea consumption on the level of CA 19-9 antigen in the human body. The level of CA 19-9 was measured in 270 healthy individuals who consumed heavy amounts of black tea. About 43.3 % of involved individuals were revealed to have elevated levels of CA 19-9. Males with high values of CA 19-9 represented the greatest number of involved individuals. The cutoff value of high levels of CA 19-9 in all individuals was ranged 69-105 U/ml. Consuming heavy amounts of black tea could be considered an important interfering factor that affects the levels of CA 19-9. The cutoff or predictive value of CA 19-9 in heavy-consuming people of black tea was determined.

  4. Identification of four new agr quorum sensing-interfering cyclodepsipeptides from a marine Photobacterium.

    Science.gov (United States)

    Kjaerulff, Louise; Nielsen, Anita; Mansson, Maria; Gram, Lone; Larsen, Thomas O; Ingmer, Hanne; Gotfredsen, Charlotte H

    2013-12-12

    During our search for new natural products from the marine environment, we discovered a wide range of cyclic peptides from a marine Photobacterium, closely related to P. halotolerans. The chemical fingerprint of the bacterium showed primarily non-ribosomal peptide synthetase (NRPS)-like compounds, including the known pyrrothine antibiotic holomycin and a wide range of peptides, from diketopiperazines to cyclodepsipeptides of 500-900 Da. Purification of components from the pellet fraction led to the isolation and structure elucidation of four new cyclodepsipeptides, ngercheumicin F, G, H, and I. The ngercheumicins interfered with expression of virulence genes known to be controlled by the agr quorum sensing system of Staphylococcus aureus, although to a lesser extent than the previously described solonamides from the same strain of Photobacterium.

  5. Identification of Four New agr Quorum Sensing-Interfering Cyclodepsipeptides from a Marine Photobacterium

    Directory of Open Access Journals (Sweden)

    Louise Kjaerulff

    2013-12-01

    Full Text Available During our search for new natural products from the marine environment, we discovered a wide range of cyclic peptides from a marine Photobacterium, closely related to P. halotolerans. The chemical fingerprint of the bacterium showed primarily non-ribosomal peptide synthetase (NRPS-like compounds, including the known pyrrothine antibiotic holomycin and a wide range of peptides, from diketopiperazines to cyclodepsipeptides of 500–900 Da. Purification of components from the pellet fraction led to the isolation and structure elucidation of four new cyclodepsipeptides, ngercheumicin F, G, H, and I. The ngercheumicins interfered with expression of virulence genes known to be controlled by the agr quorum sensing system of Staphylococcus aureus, although to a lesser extent than the previously described solonamides from the same strain of Photobacterium.

  6. Evaluation of bilirubin concentration in hemolysed samples, is it really impossible? The altitude-curve cartography approach to interfered assays.

    Science.gov (United States)

    Brunori, Paola; Masi, Piergiorgio; Faggiani, Luigi; Villani, Luciano; Tronchin, Michele; Galli, Claudio; Laube, Clarissa; Leoni, Antonella; Demi, Maila; La Gioia, Antonio

    2011-04-11

    Neonatal jaundice might lead to severe clinical consequences. Measurement of bilirubin in samples is interfered by hemolysis. Over a method-depending cut-off value of measured hemolysis, bilirubin value is not accepted and a new sample is required for evaluation although this is not always possible, especially with newborns and cachectic oncological patients. When usage of different methods, less prone to interferences, is not feasible an alternative recovery method for analytical significance of rejected data might help clinicians to take appropriate decisions. We studied the effects of hemolysis over total bilirubin measurement, comparing hemolysis-interfered bilirubin measurement with the non-interfered value. Interference curves were extrapolated over a wide range of bilirubin (0-30 mg/mL) and hemolysis (H Index 0-1100). Interference "altitude" curves were calculated and plotted. A bimodal acceptance table was calculated. Non-interfered bilirubin of given samples was calculated, by linear interpolation between the nearest lower and upper interference curves. Rejection of interference-sensitive data from hemolysed samples for every method should be based not upon the interferent concentration but upon a more complex algorithm based upon the concentration-dependent bimodal interaction between the interfered analyte and the measured interferent. The altitude-curve cartography approach to interfered assays may help laboratories to build up their own method-dependent algorithm and to improve the trueness of their data by choosing a cut-off value different from the one (-10% interference) proposed by manufacturers. When re-sampling or an alternative method is not available the altitude-curve cartography approach might also represent an alternative recovery method for analytical significance of rejected data. Copyright © 2011 Elsevier B.V. All rights reserved.

  7. Interferência em misturas de feijão Interference in bean mixtures

    Directory of Open Access Journals (Sweden)

    Janete Joanol da Silveira Mastrantonio

    2004-04-01

    Full Text Available O presente trabalho teve como objetivos examinar a magnitude dos efeitos de interferência em cultivares de feijão, quando em mistura, empregando um novo coeficiente (Coeficiente de Interferência e verificar a existência de correlações entre rendimento de grãos e seus componentes primários, para cada cultivar. Os experimentos foram conduzidos em Canguçu e Passo Fundo, RS, sendo os tratamentos compostos pelas cultivares Carioca, Guateian 6662 e Tayhú em estande puro e em duas misturas, Mis1 (equivalente a 240 mil plantas.ha-1, como em estande puro e Mis2 (120 mil plantas.ha-1. As variáveis avaliadas foram número de vagens por planta (NVP, número de sementes por vagem (NSV, peso de 100 sementes (PCS e rendimento de grãos. O delineamento experimental utilizado foi blocos casualizados com cinco repetições. Observou-se que Tayhú teve sua produtividade estimulada quando em mistura sendo este efeito bastante pronunciado sob a população de 240 mil plantas.ha-1; caracterizando a presença de efeitos positivos de interferência, sendo que Carioca e Guateian 6662 sofreram efeitos neutros quando em Mis1 e negativos quando em Mis2. Verificou-se que as correlações fenotípicas entre os componentes do rendimento dependem de cada cultivar e do ambiente em que se encontram, apresentando pouco valor em programas de melhoramento ou na predição do rendimento.This work had as main objectives 1 to examine the magnitude of interference effects on bean cultivars, under two population densities, through the use of a new coefficient (Coefficient of Interference; and 2 To verify possible correlations among grain yield and its primary components, for each cultivar. Trials were carried out in the locations of Canguçu and Passo Fundo, State of Rio Grande do Sul, Brazil, and the trataments were the cultivars Carioca, Guateian 6662 and Tayhú, under pure stand and under two mixed populations. Mixtures of cultivars were 240.000 (Mis1 and 120.000 (Mis2

  8. AI-2 quorum-sensing inhibitors affect the starvation response and reduce virulence in several Vibrio species, most likely by interfering with LuxPQ.

    Science.gov (United States)

    Brackman, Gilles; Celen, Shari; Baruah, Kartik; Bossier, Peter; Van Calenbergh, Serge; Nelis, Hans J; Coenye, Tom

    2009-12-01

    The increase of disease outbreaks caused by Vibrio species in aquatic organisms as well as in humans, together with the emergence of antibiotic resistance in Vibrio species, has led to a growing interest in alternative disease control measures. Quorum sensing (QS) is a mechanism for regulating microbial gene expression in a cell density-dependent way. While there is good evidence for the involvement of auto-inducer 2 (AI-2)-based interspecies QS in the control of virulence in multiple Vibrio species, only few inhibitors of this system are known. From the screening of a small panel of nucleoside analogues for their ability to disturb AI-2-based QS, an adenosine derivative with a p-methoxyphenylpropionamide moiety at C-3' emerged as a promising hit. Its mechanism of inhibition was elucidated by measuring the effect on bioluminescence in a series of Vibrio harveyi AI-2 QS mutants. Our results indicate that this compound, as well as a truncated analogue lacking the adenine base, block AI-2-based QS without interfering with bacterial growth. The active compounds affected neither the bioluminescence system as such nor the production of AI-2, but most likely interfered with the signal transduction pathway at the level of LuxPQ in V. harveyi. The most active nucleoside analogue (designated LMC-21) was found to reduce the Vibrio species starvation response, to affect biofilm formation in Vibrio anguillarum, Vibrio vulnificus and Vibrio cholerae, to reduce pigment and protease production in V. anguillarum, and to protect gnotobiotic Artemia from V. harveyi-induced mortality.

  9. Amiodarone and metabolite MDEA inhibit Ebola virus infection by interfering with the viral entry process.

    Science.gov (United States)

    Salata, Cristiano; Baritussio, Aldo; Munegato, Denis; Calistri, Arianna; Ha, Huy Riem; Bigler, Laurent; Fabris, Fabrizio; Parolin, Cristina; Palù, Giorgio; Mirazimi, Ali

    2015-07-01

    Ebola virus disease (EVD) is one of the most lethal transmissible infections characterized by a high fatality rate, and a treatment has not been developed yet. Recently, it has been shown that cationic amphiphiles, among them the antiarrhythmic drug amiodarone, inhibit filovirus infection. In the present work, we investigated how amiodarone interferes with Ebola virus infection. Wild-type Sudan ebolavirus and recombinant vesicular stomatitis virus, pseudotyped with the Zaire ebolavirus glycoprotein, were used to gain further insight into the ability of amiodarone to affect Ebola virus infection. We show that amiodarone decreases Ebola virus infection at concentrations close to those found in the sera of patients treated for arrhythmias. The drug acts by interfering with the fusion of the viral envelope with the endosomal membrane. We also show that MDEA, the main amiodarone metabolite, contributes to the antiviral activity. Finally, studies with amiodarone analogues indicate that the antiviral activity is correlated with drug ability to accumulate into and interfere with the endocytic pathway. Considering that it is well tolerated, especially in the acute setting, amiodarone appears to deserve consideration for clinical use in EVD. © FEMS 2015. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  10. Sub-micron period metal lattices fabricated by interfering ultraviolet femtosecond laser processing

    Science.gov (United States)

    Nakata, Yoshiki; Matsuba, Yoshiki; Miyanaga, Noriaki

    2016-05-01

    The interference pattern of a femtosecond laser has been utilized to fabricate nanostructures in the lattice. In this paper, SH (second-harmonic) waves (λ = 392.5 {{nm}}) of a femtosecond laser were applied to four beams interfering laser processing using a demagnification system as a beam correlator. The lattice constant of the resultant matrix was shortened to 760 nm. The unit structures fabricated on gold thin films were nanoholes, nanobumps, nanodrops or nanowhiskers, and their unit size was minimized compared to the case with a greater lattice constant formed by fundamental wavelengths. The radius of a nanoball on top of a nanodrop was between 42 and 76 nm, and the radius of metallic hole arrays (MHA) was 220 nm. The energy efficiency of the laser increased by 4.79 times due to better absorption coefficient of gold at ultraviolet wavelengths. In addition, the smallest lattice constant was estimated with the use of a commercial plano-convex fused-silica lens and a NIR (near-infrared) achromatic lens.

  11. Multiwavelength pyrometer for gray and non-gray surfaces in the presence of interfering radiation

    Science.gov (United States)

    Ng, Daniel L. P. (Inventor)

    1994-01-01

    A method and apparatus for detecting the temperature of gray and non-gray bodies in the presence of interfering radiation are presented. A gray body has a constant emissivity less than 1 and a non-gray body has an emissivity which varies with wavelength. The emissivity and reflectivity of the surface is determined over a range of wavelengths. Spectra are also measured of the extraneous interference radiation source and the surface of the object to be measured in the presence of the extraneous interference radiation source. An auxiliary radiation source is used to determine the reflectivity of the surface and also the emissivity. The measured spectrum of the surfaces in the presence of the extraneous interference radiation source is set equal to the emissivity of the surface multiplied by a Planck function containing a temperature term T plus the surface reflectivity multiplied by the spectrum of the extraneous interference radiation source. The equation is then solved for T to determine the temperature of the surface.

  12. Short interfering RNAs targeting a vampire-bat related rabies virus phosphoprotein mRNA.

    Science.gov (United States)

    Ono, Ekaterina Alexandrovna Durymanova; Taniwaki, Sueli Akemi; Brandão, Paulo

    The aim of this study was to assess the in vitro and in vivo effects of short-interfering RNAs (siRNAs) against rabies virus phosphoprotein (P) mRNA in a post-infection treatment for rabies as an extension of a previous report (Braz J Microbiol. 2013 Nov 15;44(3):879-82). To this end, rabies virus strain RABV-4005 (related to the Desmodus rotundus vampire bat) were used to inoculate BHK-21 cells and mice, and the transfection with each of the siRNAs was made with Lipofectamine-2000™. In vitro results showed that siRNA 360 was able to inhibit the replication of strain RABV-4005 with a 1log decrease in virus titter and 5.16-fold reduction in P mRNA, 24h post-inoculation when compared to non-treated cells. In vivo, siRNA 360 was able to induce partial protection, but with no significant difference when compared to non-treated mice. These results indicate that, despite the need for improvement for in vivo applications, P mRNA might be a target for an RNAi-based treatment for rabies. Copyright © 2017 Sociedade Brasileira de Microbiologia. Published by Elsevier Editora Ltda. All rights reserved.

  13. Small RNA pyrosequencing in the protozoan parasite Entamoeba histolytica reveals strain-specific small RNAs that target virulence genes

    Science.gov (United States)

    2013-01-01

    Background Small RNA mediated gene silencing is a well-conserved regulatory pathway. In the parasite Entamoeba histolytica an endogenous RNAi pathway exists, however, the depth and diversity of the small RNA population remains unknown. Results To characterize the small RNA population that associates with E. histolytica Argonaute-2 (EhAGO2-2), we immunoprecipitated small RNAs that associate with it and performed one full pyrosequencing run. Data analysis revealed new features of the 27nt small RNAs including the 5′-G predominance, distinct small RNA distribution patterns on protein coding genes, small RNAs mapping to both introns and exon-exon junctions, and small RNA targeted genes that are clustered particularly in sections of genome duplication. Characterization of genomic loci to which both sense and antisense small RNAs mapped showed that both sets of small RNAs have 5′-polyphosphate termini; strand-specific RT-PCR detected transcripts in both directions at these loci suggesting that both transcripts may serve as template for small RNA generation. In order to determine whether small RNA abundance patterns account for strain-specific gene expression profiles of E. histolytica virulent and non-virulent strains, we sequenced small RNAs from a non-virulent strain and found that small RNAs mapped to genes in a manner consistent with their regulation of strain-specific virulence genes. Conclusions We provided a full spectrum analysis for E. histolytica AGO2-2 associated 27nt small RNAs. Additionally, comparative analysis of small RNA populations from virulent and non-virulent amebic strains indicates that small RNA populations may regulate virulence genes. PMID:23347563

  14. Schinus terebinthifolius Leaf Extract Causes Midgut Damage, Interfering with Survival and Development of Aedes aegypti Larvae.

    Science.gov (United States)

    Procópio, Thamara Figueiredo; Fernandes, Kenner Morais; Pontual, Emmanuel Viana; Ximenes, Rafael Matos; de Oliveira, Aline Rafaella Cardoso; Souza, Carolina de Santana; Melo, Ana Maria Mendonça de Albuquerque; Navarro, Daniela Maria do Amaral Ferraz; Paiva, Patrícia Maria Guedes; Martins, Gustavo Ferreira; Napoleão, Thiago Henrique

    2015-01-01

    In this study, a leaf extract from Schinus terebinthifolius was evaluated for effects on survival, development, and midgut of A. aegypti fourth instar larvae (L4), as well as for toxic effect on Artemia salina. Leaf extract was obtained using 0.15 M NaCl and evaluated for phytochemical composition and lectin activity. Early L4 larvae were incubated with the extract (0.3-1.35%, w/v) for 8 days, in presence or absence of food. Polymeric proanthocyanidins, hydrolysable tannins, heterosid and aglycone flavonoids, cinnamic acid derivatives, traces of steroids, and lectin activity were detected in the extract, which killed the larvae at an LC50 of 0.62% (unfed larvae) and 1.03% (fed larvae). Further, the larvae incubated with the extract reacted by eliminating the gut content. No larvae reached the pupal stage in treatments at concentrations between 0.5% and 1.35%, while in the control (fed larvae), 61.7% of individuals emerged as adults. The extract (1.0%) promoted intense disorganization of larval midgut epithelium, including deformation and hypertrophy of cells, disruption of microvilli, and vacuolization of cytoplasms, affecting digestive, enteroendocrine, regenerative, and proliferating cells. In addition, cells with fragmented DNA were observed. Separation of extract components by solid phase extraction revealed that cinnamic acid derivatives and flavonoids are involved in larvicidal effect of the extract, being the first most efficient in a short time after larvae treatment. The lectin present in the extract was isolated, but did not show deleterious effects on larvae. The extract and cinnamic acid derivatives were toxic to A. salina nauplii, while the flavonoids showed low toxicity. S. terebinthifolius leaf extract caused damage to the midgut of A. aegypti larvae, interfering with survival and development. The larvicidal effect of the extract can be attributed to cinnamic acid derivatives and flavonoids. The data obtained using A. salina indicates that caution

  15. Schinus terebinthifolius Leaf Extract Causes Midgut Damage, Interfering with Survival and Development of Aedes aegypti Larvae.

    Directory of Open Access Journals (Sweden)

    Thamara Figueiredo Procópio

    Full Text Available In this study, a leaf extract from Schinus terebinthifolius was evaluated for effects on survival, development, and midgut of A. aegypti fourth instar larvae (L4, as well as for toxic effect on Artemia salina. Leaf extract was obtained using 0.15 M NaCl and evaluated for phytochemical composition and lectin activity. Early L4 larvae were incubated with the extract (0.3-1.35%, w/v for 8 days, in presence or absence of food. Polymeric proanthocyanidins, hydrolysable tannins, heterosid and aglycone flavonoids, cinnamic acid derivatives, traces of steroids, and lectin activity were detected in the extract, which killed the larvae at an LC50 of 0.62% (unfed larvae and 1.03% (fed larvae. Further, the larvae incubated with the extract reacted by eliminating the gut content. No larvae reached the pupal stage in treatments at concentrations between 0.5% and 1.35%, while in the control (fed larvae, 61.7% of individuals emerged as adults. The extract (1.0% promoted intense disorganization of larval midgut epithelium, including deformation and hypertrophy of cells, disruption of microvilli, and vacuolization of cytoplasms, affecting digestive, enteroendocrine, regenerative, and proliferating cells. In addition, cells with fragmented DNA were observed. Separation of extract components by solid phase extraction revealed that cinnamic acid derivatives and flavonoids are involved in larvicidal effect of the extract, being the first most efficient in a short time after larvae treatment. The lectin present in the extract was isolated, but did not show deleterious effects on larvae. The extract and cinnamic acid derivatives were toxic to A. salina nauplii, while the flavonoids showed low toxicity. S. terebinthifolius leaf extract caused damage to the midgut of A. aegypti larvae, interfering with survival and development. The larvicidal effect of the extract can be attributed to cinnamic acid derivatives and flavonoids. The data obtained using A. salina indicates

  16. Self-recognition mechanism between skin and suckers prevents octopus arms from interfering with each other.

    Science.gov (United States)

    Nesher, Nir; Levy, Guy; Grasso, Frank W; Hochner, Binyamin

    2014-06-02

    Controlling movements of flexible arms is a challenging task for the octopus because of the virtually infinite number of degrees of freedom (DOFs) [1, 2]. Octopuses simplify this control by using stereotypical motion patterns that reduce the DOFs, in the control space, to a workable few [2]. These movements are triggered by the brain and are generated by motor programs embedded in the peripheral neuromuscular system of the arm [3-5]. The hundreds of suckers along each arm have a tendency to stick to almost any object they contact [6-9]. The existence of this reflex could pose significant problems with unplanned interactions between the arms if not appropriately managed. This problem is likely to be accentuated because it is accepted that octopuses are "not aware of their arms" [10-14]. Here we report of a self-recognition mechanism that has a novel role in motor control, restraining the arms from interfering with each other. We show that the suckers of amputated arms never attach to octopus skin because a chemical in the skin inhibits the attachment reflex of the suckers. The peripheral mechanism appears to be overridden by central control because, in contrast to amputated arms, behaving octopuses sometime grab amputated arms. Surprisingly, octopuses seem to identify their own amputated arms, as they treat arms of other octopuses like food more often than their own. This self-recognition mechanism is a novel peripheral component in the embodied organization of the adaptive interactions between the octopus's brain, body, and environment [15, 16]. Copyright © 2014 Elsevier Ltd. All rights reserved.

  17. Breast cancer drugs dampen vascular functions by interfering with nitric oxide signaling in endothelium

    International Nuclear Information System (INIS)

    Gajalakshmi, Palanivel; Priya, Mani Krishna; Pradeep, Thangaraj; Behera, Jyotirmaya; Muthumani, Kandasamy; Madhuwanti, Srinivasan; Saran, Uttara; Chatterjee, Suvro

    2013-01-01

    the treatments of breast cancer drugs. • Breast cancer drugs induce vasoconstriction by interfering with NO pathway. • NO donors, cGMP analogs rescue breast cancer drug induced endothelial dysfunctions

  18. Breast cancer drugs dampen vascular functions by interfering with nitric oxide signaling in endothelium

    Energy Technology Data Exchange (ETDEWEB)

    Gajalakshmi, Palanivel; Priya, Mani Krishna; Pradeep, Thangaraj; Behera, Jyotirmaya; Muthumani, Kandasamy; Madhuwanti, Srinivasan; Saran, Uttara; Chatterjee, Suvro, E-mail: soovro@yahoo.ca

    2013-06-01

    the treatments of breast cancer drugs. • Breast cancer drugs induce vasoconstriction by interfering with NO pathway. • NO donors, cGMP analogs rescue breast cancer drug induced endothelial dysfunctions.

  19. Interferência de plantas daninhas na cultura do feijão-caupi Weed interference in cowpea

    Directory of Open Access Journals (Sweden)

    F.C.L. Freitas

    2009-06-01

    Full Text Available Objetivou-se com este trabalho determinar os períodos de interferência das plantas daninhas na cultura do feijão-caupi (Vigna unguiculata. A semeadura do feijão-caupi cultivar BR 16 foi realizada em julho de 2007, no sistema de plantio convencional. O delineamento experimental foi em blocos casualizados, com os tratamentos constituídos de períodos de controle ou convivência das plantas daninhas com a cultura. No primeiro grupo, a cultura permaneceu livre da interferência das plantas daninhas, por meio de capinas, nos períodos de: 0-09, 0-18, 0-27, 0-36, 0-45 e 0-60 (colheita. No segundo grupo, a cultura permaneceu sob a interferência desde a emergência até os mesmos períodos descritos anteriormente. O período crítico de prevenção à interferência (PCPI foi de 11 a 35 dias após a emergência da cultura. A interferência das plantas daninhas reduziu o estande final, o número de vagens por planta e o rendimento de grãos do feijão-caupi em até 90%.This work aimed to determine the periods of weed interference in cowpea (Vigna unguiculata, sown under the conventional system in July 2007. The experiment was arranged in randomized blocks, with the treatments consisting of periods of control or intercropping of the weeds with the crop. In the first group, the bean crop remained free of weed interference in the periods 0-09, 0-18, 0-27, 0-36, 0-45 and 0-60 (harvest. .In the second group, the bean crop remained under interference from the time of emergence up to the same periods previously described. The critical period of weed interference prevention (CPIP was from 11 to 35 days after crop emergence. Weed interference reduced the final stand, number of pods per plant, and grain yield up to 90%.

  20. Amide linkages mimic phosphates in RNA interactions with proteins and are well tolerated in the guide strand of short interfering RNAs

    Science.gov (United States)

    Mutisya, Daniel; Hardcastle, Travis; Cheruiyot, Samwel K.; Pallan, Pradeep S.; Kennedy, Scott D.; Egli, Martin; Kelley, Melissa L.; Smith, Anja van Brabant

    2017-01-01

    Abstract While the use of RNA interference (RNAi) in molecular biology and functional genomics is a well-established technology, in vivo applications of synthetic short interfering RNAs (siRNAs) require chemical modifications. We recently found that amides as non-ionic replacements for phosphodiesters may be useful modifications for optimization of siRNAs. Herein, we report a comprehensive study of systematic replacement of a single phosphate with an amide linkage throughout the guide strand of siRNAs. The results show that amides are surprisingly well tolerated in the seed and central regions of the guide strand and increase the silencing activity when placed between nucleosides 10 and 12, at the catalytic site of Argonaute. A potential explanation is provided by the first crystal structure of an amide-modified RNA–DNA with Bacillus halodurans RNase H1. The structure reveals how small changes in both RNA and protein conformation allow the amide to establish hydrogen bonding interactions with the protein. Molecular dynamics simulations suggest that these alternative binding modes may compensate for interactions lost due to the absence of a phosphodiester moiety. Our results suggest that an amide can mimic important hydrogen bonding interactions with proteins required for RNAi activity and may be a promising modification for optimization of biological properties of siRNAs. PMID:28854734

  1. Amide linkages mimic phosphates in RNA interactions with proteins and are well tolerated in the guide strand of short interfering RNAs.

    Science.gov (United States)

    Mutisya, Daniel; Hardcastle, Travis; Cheruiyot, Samwel K; Pallan, Pradeep S; Kennedy, Scott D; Egli, Martin; Kelley, Melissa L; Smith, Anja van Brabant; Rozners, Eriks

    2017-08-21

    While the use of RNA interference (RNAi) in molecular biology and functional genomics is a well-established technology, in vivo applications of synthetic short interfering RNAs (siRNAs) require chemical modifications. We recently found that amides as non-ionic replacements for phosphodiesters may be useful modifications for optimization of siRNAs. Herein, we report a comprehensive study of systematic replacement of a single phosphate with an amide linkage throughout the guide strand of siRNAs. The results show that amides are surprisingly well tolerated in the seed and central regions of the guide strand and increase the silencing activity when placed between nucleosides 10 and 12, at the catalytic site of Argonaute. A potential explanation is provided by the first crystal structure of an amide-modified RNA-DNA with Bacillus halodurans RNase H1. The structure reveals how small changes in both RNA and protein conformation allow the amide to establish hydrogen bonding interactions with the protein. Molecular dynamics simulations suggest that these alternative binding modes may compensate for interactions lost due to the absence of a phosphodiester moiety. Our results suggest that an amide can mimic important hydrogen bonding interactions with proteins required for RNAi activity and may be a promising modification for optimization of biological properties of siRNAs. © The Author(s) 2017. Published by Oxford University Press on behalf of Nucleic Acids Research.

  2. Amide linkages mimic phosphates in RNA interactions with proteins and are well tolerated in the guide strand of short interfering RNAs

    Energy Technology Data Exchange (ETDEWEB)

    Mutisya, Daniel; Hardcastle, Travis; Cheruiyot, Samwel K.; Pallan, Pradeep S.; Kennedy, Scott D.; Egli, Martin; Kelley, Melissa L.; Smith, Anja van Brabant; Rozners, Eriks

    2017-06-27

    While the use of RNA interference (RNAi) in molecular biology and functional genomics is a well-established technology, in vivo applications of synthetic short interfering RNAs (siRNAs) require chemical modifications. We recently found that amides as non-ionic replacements for phosphodiesters may be useful modifications for optimization of siRNAs. Herein, we report a comprehensive study of systematic replacement of a single phosphate with an amide linkage throughout the guide strand of siRNAs. The results show that amides are surprisingly well tolerated in the seed and central regions of the guide strand and increase the silencing activity when placed between nucleosides 10 and 12, at the catalytic site of Argonaute. A potential explanation is provided by the first crystal structure of an amide-modified RNA–DNA with Bacillus halodurans RNase H1. The structure reveals how small changes in both RNA and protein conformation allow the amide to establish hydrogen bonding interactions with the protein. Molecular dynamics simulations suggest that these alternative binding modes may compensate for interactions lost due to the absence of a phosphodiester moiety. Our results suggest that an amide can mimic important hydrogen bonding interactions with proteins required for RNAi activity and may be a promising modification for optimization of biological properties of siRNAs.

  3. Chronic pain disrupts ability to work by interfering with social function: A cross-sectional study.

    Science.gov (United States)

    Hengstebeck, Elizabeth; Roskos, Steven; Breejen, Karen; Arnetz, Bengt; Arnetz, Judy

    2017-10-01

    Some 100 million adults in the United States suffer from chronic pain. While research to date has focused primarily on pain interference with physical and psychological function and its effects on employment, few studies have examined the impact of pain interference on social functioning and its effects on employment. The aims of our study were to (1) evaluate the association between pain interference with ability to work and actual employment status among working age adults with chronic pain; and (2) evaluate pain interference with four types of functioning - cognitive, physical, psychological, and social - as possible mediators of pain interference with the ability to work. Data were collected via a self-selected sample of individuals visiting the American Chronic Pain Association (ACPA) website. The final dataset included 966 respondents. We examined the association between pain interference with the ability to work and employment in a population with chronic pain. We then analyzed pain interference with four types of functioning, physical, psychological, cognitive, and social, for their impact on the ability to work. Pain interference with ability to work was significantly inversely associated with employment status, i.e., the less that pain interfered with one's ability to work, the greater the likelihood of being employed. Moreover, pain interference with ability to work was a stronger predictor of employment status than an individual's rating of their pain intensity. Pain interference with social functioning partially mediated the effects of pain interference with cognitive and physical functioning and fully mediated the effects of pain intensity and pain interference with psychological functioning on pain interference with the ability to work. Results suggest that pain interference with social function may be a significant contributor to pain interference with ability to work in working age adults with chronic pain. In the development of effective solutions

  4. Estudio de la leucemia linfoblástica aguda: Interferón, genes supresores de tumor y el receptor T

    OpenAIRE

    Sternik, Gabriel

    1998-01-01

    En líneas celulares de origen leucémico se han encontrado deleciones en el brazo corto del cromosoma 9, donde se localizan los genes del interferón de tipo I, lo que en un principio hizo suponer que el interferón se comportaba como un gen supresor de tumor. Se propuso ver si la producción de interferón estaba alterada en las leucemias linfoblásticas agudas (LLA), y si esas alteraciones génicas estarían relacionadas con la capacidad de producción de interferón a por las células malignas al ser...

  5. Desarrollo de panuveítis por tuberculosis en paciente con esclerosis múltiple tratado con interferón beta

    Directory of Open Access Journals (Sweden)

    Lucía Echevarría Lucas

    2016-09-01

    Los linfocitos CD4+ T, leucocitos, macrófagos y granulocitos, con la producción de sus mediadores interferón gamma, IL-12 o TNF-α son fundamentales para controlar al Mycobacterium tuberculosis. Por ello, antes de introducir Interferón beta 1b, convendría realizar técnicas de screening, como la prueba de Mantoux o el interferon gamma release assay–(quantiferon-TB para detectar posibles tuberculosis latentes potencialmente activables.

  6. Períodos de interferência das plantas daninhas em algodoeiro de fibra colorida 'BRS Safira'

    OpenAIRE

    Cardoso,Gleibson Dionízio; Alves,Pedro Luís da Costa Aguiar; Beltrão,Napoleão Esberard de Macêdo; Vale,Leandro Silva do

    2010-01-01

    Objetivou-se com esse trabalho, identificar os períodos de interferência das plantas daninhas no algodoeiro de fibra colorida (BRS Safira), bem como avaliar a comunidade infestante nesta cultura. O experimento foi realizado no município de Missão Velha, CE, região do Cariri, na safra 2007/2008. Utilizou-se o delineamento experimental em blocos ao acaso, com quatro repetições, em esquema fatorial 2 x 5, sendo os fatores: modalidades de competição (com e sem competição de plantas daninhas) e pe...

  7. Optimal discrimination of optical coherent states cannot always be realized by interfering with coherent light, photon counting, and feedback

    Science.gov (United States)

    Nakahira, Kenji; Kato, Kentaro; Usuda, Tsuyoshi Sasaki

    2018-02-01

    It is well known that a minimum error quantum measurement for arbitrary binary optical coherent states can be realized by a receiver that comprises interfering with a coherent reference light, photon counting, and feedback control. We show that, for ternary optical coherent states, a minimum error measurement cannot always be realized by such a receiver. The problem of finding an upper bound on the maximum success probability of such a receiver can be formulated as a convex programming problem. We derive its dual problem and numerically find the upper bound. At least for ternary phase-shift keyed coherent states, this bound does not reach the success probability of a minimum error measurement.

  8. Angiotensin-converting enzyme inhibitor captopril prevents activation-induced apoptosis by interfering with T cell activation signals

    Science.gov (United States)

    Odaka, C; Mizuochi, T

    2000-01-01

    Captopril is an orally active inhibitor of angiotensin-converting enzyme (ACE) which is widely used as an anti-hypertensive agent. In addition to its ability to reduce blood pressure, captopril has a number of other biological activities. Recently the drug was shown to inhibit Fas-induced apoptosis in human activated peripheral T cells and human lung epithelial cells. In this study, we investigated whether captopril blocks activation-induced apoptosis in murine T cell hybridomas, and found that captopril inhibited IL-2 synthesis and apoptotic cell death upon activation with anti-CD3 antibody. In addition, captopril inhibited an inducible caspase-3-like activity during activation-induced apoptosis. On the other hand, captopril did not interfere with Fas signalling, since anti-Fas antibody-induced apoptosis in Fas+ Jurkat cells was unaffected by the drug. Furthermore, we examined whether captopril blocks activation-induced apoptosis by interfering with expression of Fas, Fas ligand (FasL), or both on T cell hybridomas. FasL expression on activated T cells was significantly inhibited by captopril, whereas up-expression of Fas was partially inhibited, as assessed by cell surface staining. Taking all data together, we conclude that captopril prevents activation-induced apoptosis in T cell hybridomas by interfering with T cell activation signals. Captopril has been reported to induce systemic lupus erythematosus syndrome, and our findings may be useful for elucidating the mechanism of captopril-induced autoimmunity. PMID:10971519

  9. Potential misinterpretation of the nutritional value of dietary fiber: correcting fiber digestibility values for nondietary gut-interfering material.

    Science.gov (United States)

    Montoya, Carlos A; Henare, Sharon J; Rutherfurd, Shane M; Moughan, Paul J

    2016-08-01

    The aim of this review is to identify the origin and implications of a nondietary material present in digesta and feces that interferes with the determination of dietary fiber in gastrointestinal contents. Negative values for ileal and fecal digestibility of dietary fiber are commonly reported in the literature for monogastric animal species, including humans. As negative values are not possible physiologically, this suggests the existence of a nondietary material in the gastrointestinal contents and feces that interferes with the accurate determination of dietary fiber digestibility when conventional methods of fiber determination are applied. To date, little attention has been given to this nondietary interfering material, which appears to be influenced by the type and concentration of fiber in the diet. Interestingly, estimates of dietary fiber digestibility increase substantially when corrected for the nondietary interfering material, which suggests that currently reported values underestimate the digestibility of dietary fiber and may misrepresent where, in the digestive tract, fermentation of fiber occurs. A new perspective of dietary fiber digestion in the gastrointestinal tract is developing, leading to a better understanding of the contribution of dietary fiber to health. © The Author(s) 2016. Published by Oxford University Press on behalf of the International Life Sciences Institute. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  10. Longitudinal assessment of TUBB3 expression in non-small cell lung cancer patients

    DEFF Research Database (Denmark)

    Jakobsen, Jan Nyrop; Santoni-Rugiu, Eric; Sørensen, Jens Benn

    2014-01-01

    INTRODUCTION: Class-III-beta-tubulin (TUBB3) expression may be a potential predictive factor for treatment with microtubule interfering cytotoxic drugs in non-small cell lung cancer (NSCLC). Potential changes in TUBB3 expression during chemotherapy may be of interest if future choice of chemother......INTRODUCTION: Class-III-beta-tubulin (TUBB3) expression may be a potential predictive factor for treatment with microtubule interfering cytotoxic drugs in non-small cell lung cancer (NSCLC). Potential changes in TUBB3 expression during chemotherapy may be of interest if future choice...... of chemotherapy is to be based on TUBB3 expression. If the biomarker expression changes during chemotherapy, biopsies before initiation of chemotherapy beyond first line may be needed if treatment decision is to be based on TUBB3 expression. Thus, the aim was to explore TUBB3 expression heterogeneity and changes......, suggesting no need for rebiopsy in case second-line chemotherapy with microtubule interfering cytotoxic treatments is necessary....

  11. A novel polyaminocarboxylate compound to treat murine pulmonary aspergillosis by interfering with zinc metabolism.

    Science.gov (United States)

    Laskaris, Paris; Vicentefranqueira, Rocío; Helynck, Olivier; Jouvion, Grégory; Calera, José Antonio; du Merle, Laurence; Suzenet, Franck; Buron, Frédéric; Alves de Sousa, Rodolphe; Mansuy, Daniel; Cavaillon, Jean-Marc; Latgé, Jean-Paul; Munier-Lehmann, Hélène; Ibrahim-Granet, Oumaima

    2018-04-09

    Aspergillus fumigatus can cause pulmonary aspergillosis in immunocompromised patients and is associated with a high mortality rate due to the lack of reliable treatment options. This opportunistic pathogen requires zinc in order to grow and cause disease. Novel compounds that interfere with fungal zinc metabolism may therefore be of therapeutic interest. We screened chemical libraries containing 59223 small molecules using a resazurin assay that compared their effects on an A. fumigatus wild type strain grown under zinc-limiting conditions and on a zinc transporter knockout strain grown under zinc-replete conditions to identify compounds affecting zinc metabolism. After a first screen 116 molecules were selected whose inhibitory effect on fungal growth was further tested by using luminescence assays and hyphal length measurements to confirm their activity, as well as to toxicity assays on HeLa cells and mice. Six compounds were selected following a re-screening, two of which were pyrazolones, two were porphyrins and two were polyaminocarboxylates. All three groups showed good in vitro activity but only one of the polyaminocarboxylates was able to significantly improve the survival of immunosuppressed mice suffering from pulmonary aspergillosis. This two-tier screening approach led us to the identification of a novel small molecule with in vivo fungicidal effects and low murine toxicity that may lead to the development of new treatment options for fungal infections either by administration of this compound as a monotherapy or as part of a combination therapy. Copyright © 2018 American Society for Microbiology.

  12. Small Data

    NARCIS (Netherlands)

    S. Pemberton (Steven)

    2014-01-01

    htmlabstractThe term “Open Data” often goes hand in hand with the term “Big Data”, where large data sets get released allowing for analysis, but the Cinderella of the Open Data ball is Small Data, small amounts of data, nonetheless possibly essential, that are too small to be put in some database or

  13. Interferência de plantas daninhas na cultura da cenoura (Daucus carota Weed interference on carrot crop (Daucus carota

    Directory of Open Access Journals (Sweden)

    M Coelho

    2009-12-01

    Full Text Available A cenoura é uma importante hortaliça no Brasil, cuja produtividade pode ser muito reduzida devido à interferência de plantas daninhas. O objetivo desta pesquisa foi avaliar efeitos de períodos de convivência das plantas daninhas na produtividade da cenoura cultivar "Brasília" e na comunidade de plantas daninhas. Os tratamentos foram constituídos de períodos crescentes de convivência ou controle das plantas daninhas. A comunidade de plantas daninhas foi avaliada quanto a número de indivíduos, matéria seca acumulada e frequência de ocorrência das espécies, e a cultura, quanto à produtividade comercial. As principais plantas daninhas foram Ageratum conyzoides, Digitaria nuda, Eleusine indica e Lepidium virginicum. A presença da comunidade de plantas daninhas durante todo o ciclo da cultura pode acarretar perdas de 94% na produtividade, evidenciando alta suscetibilidade da cenoura à interferência das plantas daninhas. Contudo, não houve período crítico de prevenção à interferência, e um único controle das plantas daninhas, entre 22 e 31 dias após a semeadura, foi suficiente para garantir a produção da cultura.Carrot is an important horticultural crop in Brazil, and its productivity may be highly reduced due to weed interference. This study evaluated the effects of weed coexistence periods on carrot cultivar 'Brasilia' yield and on the weed community. The treatments were constituted of increasing weed coexistence periods or weed-free periods. The weed community was evaluated based on number of individuals, dry matter accumulation, and frequency of occurrence; while the crop was evaluated based on marketable productivity. The main weeds were Ageratum conyzoides, Digitaria nuda, Eleusine indica, and Lepidium virginicum. The presence of the weed community throughout the crop season can cause yield losses of 94%, showing high susceptibility of the carrot crop to weed interference. However, there was no critical period for

  14. Exploiting Quorum Sensing Interfering Strategies in Gram-Negative Bacteria for the Enhancement of Environmental Applications.

    Science.gov (United States)

    Zhang, Weiwei; Li, Chenghua

    2015-01-01

    Quorum sensing (QS) is a widespread intercellular form of communication to coordinate physiological processes and cooperative activities of bacteria at the population level, and it depends on the production, secretion, and detection of small diffusible autoinducers, such as acyl-homoserine lactones (AHLs), auto-inducing oligo-peptides (AIPs) and autoinducer 2. In this review, the function of QS autoinducers of gram-negative bacteria in different aspects of wastewater treatment systems is examined. Based on research primarily performed over the past 10 years, QS involvement in the formation of biofilm and aerobic granules and changes of the microbial community and degradation/transformation pathways is discussed. In particular, the QS pathway in the role of bacterial infections and disease prevention in aquaculture is addressed. Interference of QS autoinducer-regulated pathways is considered potential treatment for a variety of environmentally related problems. This review is expected to serve as a stepping stone for further study and development strategies based on the mediation of QS-regulated pathways to enhance applications in both wastewater treatment systems and aquaculture.

  15. Exploiting quorum sensing interfering strategies in gram-negative bacteria for the enhancement of environmental applications

    Directory of Open Access Journals (Sweden)

    Weiwei eZhang

    2016-01-01

    Full Text Available Quorum sensing (QS is a widespread intercellular form of communication to coordinate physiological processes and cooperative activities of bacteria at the population level, and it depends on the production, secretion, and detection of small diffusible autoinducers, such as acyl-homoserine lactones (AHLs, auto-inducing oligo-peptides (AIPs and autoinducer 2. In this review, the function of QS autoinducers of gram-negative bacteria in different aspects of wastewater treatment systems is examined. Based on research primarily performed over the past ten years, QS involvement in the formation of biofilm and aerobic granules and changes of the microbial community and degradation/transformation pathways is discussed. In particular, the QS pathway in the role of bacterial infections and disease prevention in aquaculture is addressed. Interference of QS autoinducer-regulated pathways is considered potential treatment for a variety of environmentally related problems. This review is expected to serve as a stepping stone for further study and development strategies based on the mediation of QS-regulated pathways to enhance applications in both wastewater treatment systems and aquaculture.

  16. Exploiting Quorum Sensing Interfering Strategies in Gram-Negative Bacteria for the Enhancement of Environmental Applications

    Science.gov (United States)

    Zhang, Weiwei; Li, Chenghua

    2016-01-01

    Quorum sensing (QS) is a widespread intercellular form of communication to coordinate physiological processes and cooperative activities of bacteria at the population level, and it depends on the production, secretion, and detection of small diffusible autoinducers, such as acyl-homoserine lactones (AHLs), auto-inducing oligo-peptides (AIPs) and autoinducer 2. In this review, the function of QS autoinducers of gram-negative bacteria in different aspects of wastewater treatment systems is examined. Based on research primarily performed over the past 10 years, QS involvement in the formation of biofilm and aerobic granules and changes of the microbial community and degradation/transformation pathways is discussed. In particular, the QS pathway in the role of bacterial infections and disease prevention in aquaculture is addressed. Interference of QS autoinducer-regulated pathways is considered potential treatment for a variety of environmentally related problems. This review is expected to serve as a stepping stone for further study and development strategies based on the mediation of QS-regulated pathways to enhance applications in both wastewater treatment systems and aquaculture. PMID:26779175

  17. Recapitulation of the cellular xeroderma pigmentosum-variant phenotypes using short interfering RNA for DNA polymerase H.

    Science.gov (United States)

    Laposa, Rebecca R; Feeney, Luzviminda; Cleaver, James E

    2003-07-15

    The lesion-specific DNA polymerase POLH gene is mutated in xeroderma pigmentosum variant (XP-V) patients who exhibit an increased skin cancer incidence from UV exposure. Normal cells in which POLH expression was reduced using short interfering RNAs (siRNAs) were compared with the XP-V cellular phenotype that results from naturally occurring inactivating mutations. Stable clones expressing siRNA had partially reduced POLH protein levels, and intermediate levels of UV sensitivity and S phase checkpoint activation, but similar levels of Mre11 foci as in XP-V cells. Therefore, suppression of POLH expression levels by siRNA recapitulates most of the phenotypes seen in cells from XP-V patients with inactivating mutations in POLH.

  18. Organized metamaterials comprised of gold nanoneedles in a lattice generated on silicon (100) wafer substrates by interfering femtosecond laser processing

    Science.gov (United States)

    Nakata, Yoshiki; Momoo, Kazuma; Miyanaga, Noriaki; Hiromoto, Takuya; Tsuchida, Kunio

    2013-07-01

    Interfering femtosecond (fs) laser processing has been applied to fabricate organized metamaterials on substrates. We have named the unit structures as nanowhiskers, nanoneedles, nanodrops, and nanocrowns. The processes used for formation of these structures are analogous to the motion of a liquid as captured by a high-speed CCD camera; these structures are fabricated via liquid motion of a metallic thin film on solid substrates. From the perspective of a practical, the adaptability of this technique to silicon technology, including lithography, is very important. In this paper, Au nanoneedles on nanobumps in a lattice structure were fabricated on silicon (100) substrates. In addition, the use of a zeroth-order beam, which has been excluded in past experiments, was shown to result in a low photon cost.

  19. Using machine learning and high-throughput RNA sequencing to classify the precursors of small non-coding RNAs

    OpenAIRE

    Ryvkin, Paul; Leung, Yuk Yee; Ungar, Lyle H.; Gregory, Brian D.; Wang, Li-San

    2013-01-01

    Recent advances in high-throughput sequencing allow researchers to examine the transcriptome in more detail than ever before. Using a method known as high-throughput small RNA-sequencing, we can now profile the expression of small regulatory RNAs such as microRNAs and small interfering RNAs (siRNAs) with a great deal of sensitivity. However, there are many other types of small RNAs (

  20. Deep sequencing of virus-infected cells reveals HIV-encoded small RNAs

    NARCIS (Netherlands)

    Schopman, Nick C. T.; Willemsen, Marcel; Liu, Ying Poi; Bradley, Ted; van Kampen, Antoine; Baas, Frank; Berkhout, Ben; Haasnoot, Joost

    2012-01-01

    Small virus-derived interfering RNAs (viRNAs) play an important role in antiviral defence in plants, insects and nematodes by triggering the RNA interference (RNAi) pathway. The role of RNAi as an antiviral defence mechanism in mammalian cells has been obscure due to the lack of viRNA detection.

  1. Small RNAs and the control of transposons and viruses in Drosophila.

    NARCIS (Netherlands)

    Rij, R.P. van; Berezikov, E.

    2009-01-01

    RNA interference (RNAi) - post-transcriptional gene silencing guided by small interfering RNA (siRNA) - is an important antiviral defense mechanism in insects and plants. Several recent studies in Drosophila identified endogenous siRNAs corresponding to transposons, to structured cellular

  2. Divergent patterns of endogenous small RNA populations from seed and vegetative tissues of Glycine max

    Science.gov (United States)

    Background: Small non-coding RNAs (smRNAs) are known to have major roles in gene regulation in eukaryotes. In plants, knowledge of the biogenesis and mechanisms of action of smRNA classes including microRNAs (miRNAs), short interfering RNAs (siRNAs), and trans-acting siRNAs (tasiRNAs) has been gaine...

  3. An interfering dot-probe task facilitates the detection of mock crime memory in a reaction time (RT)-based concealed information test.

    Science.gov (United States)

    Hu, Xiaoqing; Evans, Angela; Wu, Haiyan; Lee, Kang; Fu, Genyue

    2013-02-01

    The present study aimed to test the hypothesis that an interfering task in the concealed information test will help the detection of concealed memory based on participants' behavioral performance (e.g. reaction time, error rate). Here, after participants enacted a mock crime, they were introduced to a concealed information test either with or without an interfering dot-probe task. Results showed that the RT-based pure-CIT (without interference) can detect concealed memory well above chance (AUC=.88). The detection efficiency was higher (AUC=.94) in the interference-CIT based on participants' performance of the interfering task. The findings suggested that the elevation of cognitive workload could possibly increase the detection efficiency of concealed memory based on behavioral measures. Copyright © 2012 Elsevier B.V. All rights reserved.

  4. Small Data

    OpenAIRE

    Pemberton, Steven

    2014-01-01

    htmlabstractThe term “Open Data” often goes hand in hand with the term “Big Data”, where large data sets get released allowing for analysis, but the Cinderella of the Open Data ball is Small Data, small amounts of data, nonetheless possibly essential, that are too small to be put in some database or online dataset to be put to use. RDFa is a technology that allows Cinderella to go to the ball.

  5. The siRNA-mediated knockdown of GluN3A in 46C-derived neural stem cells affects mRNA expression levels of neural genes, including known iGluR interactors

    Science.gov (United States)

    Eilebrecht, Elke; Schöneborn, Hendrik; Neumann, Sebastian; Benecke, Arndt G.; Hollmann, Michael

    2018-01-01

    For years, GluN3A was solely considered to be a dominant-negative modulator of NMDARs, since its incorporation into receptors alters hallmark features of conventional NMDARs composed of GluN1/GluN2 subunits. Only recently, increasing evidence has accumulated that GluN3A plays a more diversified role. It is considered to be critically involved in the maturation of glutamatergic synapses, and it might act as a molecular brake to prevent premature synaptic strengthening. Its expression pattern supports a putative role during neural development, since GluN3A is predominantly expressed in early pre- and postnatal stages. In this study, we used RNA interference to efficiently knock down GluN3A in 46C-derived neural stem cells (NSCs) both at the mRNA and at the protein level. Global gene expression profiling upon GluN3A knockdown revealed significantly altered expression of a multitude of neural genes, including genes encoding small GTPases, retinal proteins, and cytoskeletal proteins, some of which have been previously shown to interact with GluN3A or other iGluR subunits. Canonical pathway enrichment studies point at important roles of GluN3A affecting key cellular pathways involved in cell growth, proliferation, motility, and survival, such as the mTOR pathway. This study for the first time provides insights into transcriptome changes upon the specific knockdown of an NMDAR subunit in NSCs, which may help to identify additional functions and downstream pathways of GluN3A and GluN3A-containing NMDARs. PMID:29438442

  6. Inhibition of Androgen Receptor Expression with Small Interfering RNA Enhances Cancer Cell Apoptosis by Suppressing Survival Factors in Androgen Insensitive, Late Stage LNCaP Cells

    Directory of Open Access Journals (Sweden)

    Sang Soo Kim

    2013-01-01

    Full Text Available Introduction.The aim was to evaluate the changes of androgen receptor (AR expression quantitatively and to identify influence of AR on cancer related survival markers in LNCap cell line. Materials and Methods. We compared expressions of AR, heat shock protein 27 (HSP27, clusterin (CLU, glucose-related protein 78 (GRP78, and cellular FLICE-like inhibitory protein (c-FLIP and their genes between es-LNCaP (less than 33 times subcultured, L-33, ls-LNCaP (over 81 times subcultured, H-81, and si-LNCaP (AR siRNA transfected ls-LNCaP by Western blotting and RT-PCR. Results. The expressions of AR, HSP27, CLU, GRP78, and c-FLIP were increased in ls-LNCaP compared with es-LNCaP (AR, 157%; HSP27, 132%; CLU, 146%; GRP78, 138%; c-FLIP, 152%. However, in si-LNCaP cell line, protein expressions were reversed to the level of es-LNCaP cell lines (25, 102, 109, 98, and 101%, and gene expressions on real-time PCR were also reversed to the expression level of es-LNCaP (ls-LNCaP: 179, 156, 133, 123, and 167%; si-LNCaP: 22, 93, 103, 112, and 107%. Conclusions. This finding suggests that androgen receptor can be related to the increased expression of cancer related survival markers such as HSP27, GRP78, CLU, and c-FLIP in late stage prostate cancer, and also inhibition of AR gene can be a therapeutic target in this stage of cancer.

  7. Postexposure Application of Fas Receptor Small-Interfering RNA to Suppress Sulfur Mustard-Induced Apoptosis in Human Airway Epithelial Cells: Implication for a Therapeutic Approach

    Science.gov (United States)

    2013-01-01

    decreased both apoptotic and necrotic cell populations. Bronchoalveolar lavage fluid (BALF) of rats exposed to SM (1 mg/kg, 50 minutes) revealed a...lung injury; BALF, bronchoalveolar lavage fluid; BEBM, basal cell growth medium; DISC, death-inducing signaling complex; DR, death receptor; ELISA...exposure, the rats were euthanized, and blood and bronchoalveolar lavage fluid (BALF) were collected for biochemical analyses. BALF was collected by

  8. The SMAC mimetic BV6 sensitizes colorectal cancer cells to ionizing radiation by interfering with DNA repair processes and enhancing apoptosis

    International Nuclear Information System (INIS)

    Hehlgans, Stephanie; Oppermann, Julius; Reichert, Sebastian; Fulda, Simone; Rödel, Claus; Rödel, Franz

    2015-01-01

    In the present study, we aimed to investigate the effect of counteracting inhibitor of apoptosis (IAP) proteins using the small molecule Second Mitochondria-derived Activator of Caspase (SMAC) mimetic BV6 in combination with ionizing radiation on apoptosis, cell cycle regulation, DNA double-strand break (DSB) repair, three-dimensional (3D) clonogenic survival and expression of IAPs in colorectal carcinoma cells. Colorectal cancer cell lines (HCT-15, HT-29, SW480) were subjected to BV6 treatment (0–4 μM) with or without irradiation (2–8 Gy, single dose) followed by MTT, Caspase 3/7 activity, γH2AX/53BP1 foci assays, AnnexinV staining, cell cycle analysis, 3D colony forming assays and Western blotting (cellular IAP1 (cIAP1) and cIAP2, Survivin, X-linked IAP (XIAP)). BV6 treatment decreased cell viability and significantly increased irradiation-induced apoptosis as analyzed by Caspase 3/7 activity, AnnexinV-positive and subG1 phase cells. While basal 3D clonogenic survival was decreased in a cell line-dependent manner, BV6 significantly enhanced cellular radiosensitivity of all cell lines in a concentration-dependent manner and increased the number of radiation-induced γH2AX/53BP1-positive foci. Western blot analysis revealed a markedly reduced cIAP1 expression at 4 h after BV6 treatment in all cell lines, a substantial reduction of XIAP expression in SW480 and HT-29 cells at 24 h and a slightly decreased cIAP2 expression in HCT-15 cells at 48 h after treatment. Moreover, single or double knockdown of cIAP1 and XIAP resulted in significantly increased residual γH2AX/53BP1-positive foci 24 h after 2 Gy and radiosensitization relative to control small interfering RNA (siRNA)-treated cells. The SMAC mimetic BV6 induced apoptosis and hampered DNA damage repair to radiosensitize 3D grown colorectal cancer cells. Our results demonstrate IAP targeting as a promising strategy to counteract radiation resistance of colorectal cancer cells. The online version of this

  9. Interferência de plantas daninhas no crescimento e nutrição de plantas jovens de Coffea arabica L

    OpenAIRE

    Fialho, Cíntia Maria Teixeira

    2010-01-01

    Apesar da grande área ocupada pelo café no território brasileiro a produtividade média desta cultura no Brasil é baixa. Dentre os vários fatores que contribuem para isto destaca-se a interferência das plantas daninhas, que competem pelos recursos água, luz e nutrientes. Na fase inicial de crescimento do cafeeiro é considerado uma das fases mais sensíveis à interferência das plantas daninhas, sobretudo, na linha de cultivo da cultura. Porém, a manutenção da lavoura durante todo o ciclo, livre ...

  10. Terapia combinada de criocirugía e interferón alfa-2b humano recombinante en el condiloma acuminado

    OpenAIRE

    Alfonso Trujillo , Israel

    2015-01-01

    Las continuas recidivas de lcondiloma acuminado hace necesario la búsqueda constante de alternativas terapéuticas. Para evaluar la eficacia terapéutica y seguridad del interferón alfa-2b asociado a criocirugía en el condiloma acuminado fue realizado un ensayo clínico abierto en 170 pacientes del hospital “Hermanos Ameijeiras” que fueron aleatorizados a recibir durante 6 semanas (grupo A) 3 x 106 UI de interferón subcutáneo, 3 veces por semana y aplicación quincenal de criocirugía o (grupo B) ...

  11. Interferência das plantas daninhas sobre a produtividade e qualidade de cenoura Weed interference in carrot yield and quality

    Directory of Open Access Journals (Sweden)

    I.A.A. Soares

    2010-06-01

    Full Text Available Com o objetivo de avaliar a interferência das plantas daninhas sobre a produtividade e qualidade de cenoura (Daucus carota, foi realizado um experimento no período de julho a outubro de 2007, em Mossoró-RN. O delineamento experimental utilizado foi o de blocos casualizados, com seis tratamentos e quatro repetições. Os tratamentos consistiram de seis períodos de controle de plantas daninhas, em que a cultura da cenoura permaneceu livre da competição com essas plantas, por meio de capinas, a partir da emergência: 0-12, 0-24, 0-36, 0-48, 0-60 e 0-72 dias (testemunha mantida no limpo. As características avaliadas foram: produtividade comercial de raízes, teores de sólidos solúveis (SS, acidez total (AT, vitamina C e pH de raízes. A produtividade comercial de raízes de cenoura foi alterada pela convivência da cultura com as plantas daninhas, a qual respondeu a capinas até os 40 e 37 DAE, tolerando-se perdas de produtividade de 5 e 10%, respectivamente, em relação ao tratamento mantido no limpo durante todo o ciclo. Os teores de SS e de vitamina C não foram influenciados pela interferência das plantas daninhas, ao passo que a maior convivência da cultura com as plantas daninhas resultou em acidez total e pH das raízes mais elevados e menor relação sólidos solúveis/acidez total.This work aimed to evaluate weed interference in yield and quality of carrots (Daucus carota. An experiment was carried out in a randomized block design, with four replications. The treatments were composed of six periods of weed control (0-12, 0-24, 0-36, 0-48, 0-60 and 0-72 days after emergence (DAE. The characteristics evaluated were: yield of commercial roots, total soluble solids (TSS, total titratable acidity (TTA, vitamin C, TSS/TTA ratio and pH of roots. The commercial root yields decreased with weed interference, with weed control being required until 36 DAE. Root TSS rates and vitamin C did not vary with weed interference. The presence of

  12. Cordia verbenacea DC e Mikania sp.: interferência no ensaio de controle da qualidade microbiológico

    Directory of Open Access Journals (Sweden)

    Catarina Bernardes PEREIRA ; Suelen de Castro FONSECA; Lorena Ferreira GOMES; Felipe Lipparelli TIRONI;Pérola Oliveira MAGALHÃES , Dâmaris SILVEIRA , Yris Maria FONSECA-BAZZO

    2014-12-01

    Full Text Available Este estudo visa avaliar a contaminação microbiana de Mikania sp. (droga vegetal, tintura e xarope e Cordia verbenacea (droga vegetal, tintura e pomada. Além disso, foi investigada a possível interferência ocasionada pelos metabólitos secundários presentes nos dois derivados vegetais. A contaminação microbiana foi determinada seguindo o método de semeadura em profundidade. O estudo da interferência no método de avaliação da qualidade microbiológica foi realizado por determinação da recuperação de microrganismos viáveis, utilizando as cepas Escherichia coli (ATCC 25922 e Candida albicans (ATCC 90028. Na avaliação da qualidade microbiológica, as folhas secas oriundas de C. verbenacea e Mikania sp. apresentaram 4,5 x 104 UFC/g e 2,08 x 104 UFC/g de bactérias, respectivamente. Em relação à tintura de C. verbenacea, foi encontrada a contagem de 3,3 x 103 UFC/mL para bolores e leveduras e 2,2 x 103 UFC/mL para bactérias. Para a pomada contendo a tintura de C. verbenacea foram encontradas 1,1 x 103 UFC/g de bactérias, e não houve crescimento de fungos. No xarope não foi observado crescimento de bactérias, bolores e leveduras em nenhuma das repetições realizadas. Quanto à atividade antimicrobiana, os produtos derivados das duas espécies mostraram inibir o crescimento das cepas de E. coli e C. albicans. Assim, a presença de metabólitos secundários com atividade antimicrobiana em C. verbenacea e Mikania sp. parece interferir na avaliação da qualidade microbiológica de produtos derivados da droga vegetal.

  13. Small hydro

    International Nuclear Information System (INIS)

    Bennett, K.; Tung, T.

    1995-01-01

    A small hydro plant in Canada is defined as any project between 1 MW and 15 MW but the international standard is 10 MW. The global market for small hydro development was considered good. There are some 1000 to 2000 MW of generating capacity being added each year. In Canada, growth potential is considered small, primarily in remote areas, but significant growth is anticipated in Eastern Europe, Africa and Asia. Canada with its expertise in engineering, manufacturing and development is considered to have a good chance to take advantage of these growing markets

  14. Small Families

    Science.gov (United States)

    ... attention and educational advantages, which generally raise her self-esteem. Children in small families, especially first and only ... be for you both to accept the increasing definition of personality that needs to occur as she ...

  15. SMALL NONCODING RNA AS PERSPECTIVE BIOMARKERS: BIOGENESIS AND THERAPEUTIC STRATIGIES

    Directory of Open Access Journals (Sweden)

    V. V. Tiguntsev

    2016-01-01

    Full Text Available The review presents the opening story, biogenesis and functions of basic groups of human’s small noncoding RNA: microRNA and short interfering RNA. These RNA molecules inhibit gene expression during translation by RNA interference. It was found that microRNA and short interfering RNA circulate in bioliquids and can serve as biomarkers of different human diseases because of its conservative sequences, tissue specificity and resistance to environment factors. The paper considers techniques to study noncoding RNA (cloning, bioinformatics analysis and hybridization methods: northern-blotting, RT-PCR, in situ hybridization, microarray analysis, reporter analysis. Possible noncoding RNA-targeted therapy can suggest delivery microRNA, anti-microRNA, antagomirs, microRNAsponges to target tissue by virus molecules, liposomes or nanoparticles. 

  16. Interferência de plantas daninhas sobre a produtividade da mandioca (Manihot esculenta Weed interference in cassava (Manihot esculenta yield

    Directory of Open Access Journals (Sweden)

    J.A.A. Albuquerque

    2008-06-01

    Full Text Available O manejo inadequado das plantas daninhas é uma das principais causas da baixa produtividade da cultura da mandioca no Brasil. Objetivou-se com este trabalho identificar as espécies de plantas daninhas infestantes da cultura da mandioca e o grau de interferência que estas exercem sobre o cultivo, em função do período de convivência com a cultura. Dois experimentos foram realizados em áreas adjacentes, no município de Viçosa-MG, utilizando-se o cultivar Cacauzinha, do grupo das mandiocas mansas. O delineamento experimental adotado foi em blocos casualizados, com sete tratamentos e quatro repetições. Os tratamentos do primeiro experimento foram compostos por períodos iniciais de convivência da cultura com as plantas daninhas: 25, 50, 75, 100 e 125 dias após o plantio (DAP; no segundo experimento, as plantas de mandioca, inicialmente, permaneceram livres das plantas daninhas pelos mesmos períodos. Em ambos os experimentos adotou-se o espaçamento de 1,0 x 0,5 m, sendo a área útil da parcela constituída pelas duas linhas centrais, deixando-se 1,0 m em cada extremidade como bordaduras frontais, totalizando 8,0 m². As plantas daninhas foram avaliadas aos 25, 50, 75, 100, 125, 150, 175, 200, 225, 250, 275, 300, 325 e 350 DAP. As características produtividade de raízes, peso da parte aérea, índice de colheita, teor de amido e matéria seca das raízes foram avaliadas aos 12 meses após o plantio. As espécies de plantas daninhas que predominaram na área experimental foram: Bidens pilosa, Raphanus raphanistrum, Cyperus rotundus e Commelina benghalensis, com a primeira delas predominando em quase todas as épocas de coletas. Os períodos de convivência com as plantas daninhas não interferiram nos índices de colheita, teor de amido e matéria seca das raízes. Todavia, considerando a produtividade de raízes, o final do período anterior à interferência foi próximo dos 25 dias, e o período crítico de prevenção da interfer

  17. Small RNA Profiling in Dengue Virus 2-Infected Aedes Mosquito Cells Reveals Viral piRNAs and Novel Host miRNAs

    NARCIS (Netherlands)

    Miesen, P.; Ivens, A.; Buck, A.H.; Rij, R.P. van

    2016-01-01

    In Aedes mosquitoes, infections with arthropod-borne viruses (arboviruses) trigger or modulate the expression of various classes of viral and host-derived small RNAs, including small interfering RNAs (siRNAs), PIWI interacting RNAs (piRNAs), and microRNAs (miRNAs). Viral siRNAs are at the core of

  18. Interfering with bacterial gossip

    DEFF Research Database (Denmark)

    Bjarnsholt, Thomas; Tolker-Nielsen, Tim; Givskov, Michael

    2011-01-01

    defense. Antibiotics exhibit a rather limited effect on biofilms. Furthermore, antibiotics have an ‘inherent obsolescence’ because they select for development of resistance. Bacterial infections with origin in bacterial biofilms have become a serious threat in developed countries. Pseudomonas aeruginosa...... that appropriately target bacteria in their relevant habitat with the aim of mitigating their destructive impact on patients. In this review we describe molecular mechanisms involved in “bacterial gossip” (more scientifically referred to as quorum sensing (QS) and c-di-GMP signaling), virulence, biofilm formation......, resistance and QS inhibition as future antimicrobial targets, in particular those that would work to minimize selection pressures for the development of resistant bacteria....

  19. RNA-Mediated Regulation of HMGA1 Function

    Directory of Open Access Journals (Sweden)

    Arndt G. Benecke

    2015-05-01

    Full Text Available The high mobility group protein A1 (HMGA1 is a master regulator of chromatin structure mediating its major gene regulatory activity by direct interactions with A/T-rich DNA sequences located in the promoter and enhancer regions of a large variety of genes. HMGA1 DNA-binding through three AT-hook motifs results in an open chromatin structure and subsequently leads to changes in gene expression. Apart from its significant expression during development, HMGA1 is over-expressed in virtually every cancer, where HMGA1 expression levels correlate with tumor malignancy. The exogenous overexpression of HMGA1 can lead to malignant cell transformation, assigning the protein a key role during cancerogenesis. Recent studies have unveiled highly specific competitive interactions of HMGA1 with cellular and viral RNAs also through an AT-hook domain of the protein, significantly impacting the HMGA1-dependent gene expression. In this review, we discuss the structure and function of HMGA1-RNA complexes during transcription and epigenomic regulation and their implications in HMGA1-related diseases.

  20. siRNA-mediated methylation of Arabidopsis telomeres

    Czech Academy of Sciences Publication Activity Database

    Vrbský, Jan; Akimcheva, S.; Watson, M.; Turner, T.L.; Daxinger, L.; Vyskot, Boris; Aufsatz, W.; Říha, K.

    2010-01-01

    Roč. 6, č. 6 (2010), s. 1-12 ISSN 1553-7390 R&D Projects: GA MŠk(CZ) LC06004 Institutional research plan: CEZ:AV0Z50040507; CEZ:AV0Z50040702 Keywords : DNA methylation * siRNA * telomere Subject RIV: BO - Biophysics Impact factor: 9.543, year: 2010

  1. Adam Small

    African Journals Online (AJOL)

    Owner

    oudste dogter (MOOC 29304). Jan Small (vroeër: Jan Dampies) het ek as Oupa Jan geken en Fatimah was vir my Ouma Tiema. Uncle erken ruiterlik sy ma se sterk invloed op sy verbeelding en lewensbenadering, soos hy dit ietwat enigmaties gestel het: 'My skryfwerk lê iewers.' In sy huldeblyk,. “Onaf gedig”, wat hy tydens ...

  2. Taurine blocks ATP-sensitive potassium channels of rat skeletal muscle fibres interfering with the sulphonylurea receptor.

    Science.gov (United States)

    Tricarico, D; Barbieri, M; Camerino, D C

    2000-06-01

    Taurine is a sulphonic aminoacid present in high amounts in various tissues including cardiac and skeletal muscles showing different properties such as antioxidative, antimyotonic and anti-schaemic effects. The cellular mechanism of action of taurine is under investigation and appears to involve the interaction of the sulphonic aminoacid with several ion channels. Using the patch-clamp technique we studied the effects of taurine in rat skeletal muscle fibres on ATP-sensitive K(+) channel (K(ATP)) immediately after excision and on channels that underwent rundown. The cytoplasmic application of 20 mM of taurine reduced the K(ATP) current; this effect was reverted by washout of the drug solution. In this experimental condition the IC(50) was 20.1 mM. After rundown, taurine inhibited the K(ATP) current with similar efficacy. Competition experiments showed that taurine shifted the dose-response inhibition curve of glybenclamide to the left on the log-dose axis without significantly affecting those of ATP or Ca(2+) ion. Single channel recording revealed that taurine affects the close state of the channel prolonging it and reducing the bursts duration. Our data indicate that taurine inhibits the muscular K(ATP) channel interfering with the glybenclamide site on the sulphonylurea receptor of the channel or on the site allosterically coupled to it. During ischaemia and hypoxia, the skeletal and heart muscles undergo several changes; for example, the activation of K(ATP) channels and loss of the intracellular taurine content. The depletion of taurine during ischaemia would contribute to the early activation of K(ATP) channels and salvage the intracellular ATP content.

  3. Non-healing foot ulcers in diabetic patients: general and local interfering conditions and management options with advanced wound dressings.

    Science.gov (United States)

    Uccioli, Luigi; Izzo, Valentina; Meloni, Marco; Vainieri, Erika; Ruotolo, Valeria; Giurato, Laura

    2015-04-01

    Medical knowledge about wound management has improved as recent studies have investigated the healing process and its biochemical background. Despite this, foot ulcers remain an important clinical problem, often resulting in costly, prolonged treatment. A non-healing ulcer is also a strong risk factor for major amputation. Many factors can interfere with wound healing, including the patient's general health status (i.e., nutritional condition indicated by albumin levels) or drugs such as steroids that can interfere with normal healing. Diabetic complications (i.e., renal insufficiency) may delay healing and account for higher amputation rates observed in diabetic patients under dialysis treatment. Wound environment (e.g., presence of neuropathy, ischaemia, and infection) may significantly influence healing by interfering with the physiological healing cascade and adding local release of factors that may worsen the wound. The timely and well-orchestrated release of factors regulating the healing process, observed in acute wounds, is impaired in non-healing wounds that are blocked in a chronic inflammatory phase without progressing to healing. This chronic phase is characterised by elevated protease activity (EPA) of metalloproteinases (MMPs) and serine proteases (e.g., human neutrophil elastase) that interfere with collagen synthesis, as well as growth factor release and action. EPA (mainly MMP 9, MMP-8 and elastase) and inflammatory factors present in the wound bed (such as IL-1, IL-6, and TNFa) account for the catabolic state of non-healing ulcers. The availability of wound dressings that modulate EPA has added new therapeutic options for treating non-healing ulcers. The literature confirms advantages obtained by reducing protease activity in the wound bed, with better outcomes achieved by using these dressings compared with traditional ones. New technologies also allow a physician to know the status of the wound bed environment, particularly EPA, in a clinical

  4. Cloned defective interfering influenza virus protects ferrets from pandemic 2009 influenza A virus and allows protective immunity to be established.

    Directory of Open Access Journals (Sweden)

    Nigel J Dimmock

    Full Text Available Influenza A viruses are a major cause of morbidity and mortality in the human population, causing epidemics in the winter, and occasional worldwide pandemics. In addition there are periodic outbreaks in domestic poultry, horses, pigs, dogs, and cats. Infections of domestic birds can be fatal for the birds and their human contacts. Control in man operates through vaccines and antivirals, but both have their limitations. In the search for an alternative treatment we have focussed on defective interfering (DI influenza A virus. Such a DI virus is superficially indistinguishable from a normal virus but has a large deletion in one of the eight RNAs that make up the viral genome. Antiviral activity resides in the deleted RNA. We have cloned one such highly active DI RNA derived from segment 1 (244 DI virus and shown earlier that intranasal administration protects mice from lethal disease caused by a number of different influenza A viruses. A more cogent model of human influenza is the ferret. Here we found that intranasal treatment with a single dose of 2 or 0.2 µg 244 RNA delivered as A/PR/8/34 virus particles protected ferrets from disease caused by pandemic virus A/California/04/09 (A/Cal; H1N1. Specifically, 244 DI virus significantly reduced fever, weight loss, respiratory symptoms, and infectious load. 244 DI RNA, the active principle, was amplified in nasal washes following infection with A/Cal, consistent with its amelioration of clinical disease. Animals that were treated with 244 DI RNA cleared infectious and DI viruses without delay. Despite the attenuation of infection and disease by DI virus, ferrets formed high levels of A/Cal-specific serum haemagglutination-inhibiting antibodies and were solidly immune to rechallenge with A/Cal. Together with earlier data from mouse studies, we conclude that 244 DI virus is a highly effective antiviral with activity potentially against all influenza A subtypes.

  5. Mecanismos efectores del interferón gamma contra la infección por Toxoplasma gondii

    Directory of Open Access Journals (Sweden)

    Jorge Enrique Gómez

    1999-12-01

    Full Text Available Toxoplasma gondiies un protozoario parásito de desarrollo intracelular. La enfermedad humana producida por T: gondii es una causa importante de morbilidad y mortalidad neonatal y en pacientes inmunodeprimidos. En esta reseña, se revisan los conocimientos actuales sobre los mecanismos efectores del interferón gamma (IFN y, la principal citocina protectora contra Igondii, incluyendo los resultados que hemos obtenido en un modelo de infección in vifro de células humanas monocitarias (THPI. El IFN y protege las células humanas contra T gondii por mecanismos diferentes a aquéllos con los que protege las células de ratón. En el modelo de infección de célulasTHP1, el IFN y protege por dos mecanismos independientes. Un primer efecto es la reducción del porcentaje de células parasitadas, el cual está ligado a una disminución de la actividad PLA, parasitaria y celular. Se trata de un nuevo mecanismo efector del IFN y contra la infección toxoplásmica, diferente a los mecanismos parasiticidas y parasitostáticos previamente descritos. Un segundo efecto ocurre por interrupción del crecimiento parasitario intracelular a través de la activación de la enzima indoleamina-oxigenasa que degrada el triptófano, lo que constituye un efecto parasitostático. Contrariamente a lo que ocurre en el modelo de infección de células monocitarias de ratón, la producción de óxido nítrico (NO no juega un papel determinante en los monocitos humanos.

  6. Correction methodology for the spectral interfering γ-rays overlapping to the analytical peaks used in the analysis of 232Th.

    Science.gov (United States)

    Yücel, H; Köse, E; Esen, A N; Bor, D

    2011-06-01

    In the γ-ray spectrometric analysis of the radionuclides, a correction factor is generally required for the spectral interfering γ-rays in determining the net areas of the analytical peaks because some interfering γ-rays often might contribute to the analytical peaks of interest. In present study, a correction methodology for the spectral interfering γ-rays (CSI) is described. In particular, in the analysis of (232)Th contained in samples, the interfering γ-rays due to (226)Ra, (235)U, (238)U and their decay products often overlap to the peaks of interest from (232)Th decay products, and vise versa. For the validation of the proposed CSI method, several certified reference materials (CRM) containing U and Th were measured by using a 76.5% efficient n-type Ge detector. The required correction factors were quantified for spectral interference, self-absorption and true coincidence summing (TCS) effects for the relevant γ-rays. The measured results indicate that if one ignores the contributions of the interfering γ-rays to the analytical peaks at 583.2 keV of (208)Tl and 727.3 keV of (212)Bi, this leads to a significantly systematic influence on the resulted activities of (232)Th. The correction factors required for spectral interference and TCS effects are estimated to be ∼13.6% and ∼15.4% for 583.2 keV peak. For the 727.3 keV peak, the correction factor is estimated to be ∼15% for spectral interference, and ∼5% for the TCS effects at the presently used detection geometry. On the other hand, the measured results also indicate that ignoring the contribution of the interfering γ-rays to the areas of the analytical peaks at 860.6 keV of (208)Tl, 338.3 and 911.2 keV of (228)Ac does not lead to any significant systematic influence on the (232)Th analysis. Because these factors are remained generally less than ∼5%, i.e., within overall uncertainty limits. The present study also showed that in view of both the spectral interference and TCS effects, the

  7. Períodos de interferência de plantas daninhas na cultura do quiabo Periods of weed interference in okra crop

    Directory of Open Access Journals (Sweden)

    L.P.S Bachega

    2013-03-01

    Full Text Available Poucas pesquisas têm sido realizadas sobre interferência de plantas daninhas na cultura do quiabo. Objetivou-se com este trabalho estimar os períodos de interferência da comunidade infestante no quiabeiro. Um experimento de campo foi conduzido sob dois grupos de tratamentos, mantendo períodos crescentes de 0 (testemunha, 7, 21, 28, 35, 42, 49, 63, 77, 91 e 105 dias após a emergência da cultura (DAE, com e sem controle das plantas daninhas. As plantas daninhas com maior importância relativa foram Portulaca oleracea, Nicandra physaloides e Eleusine indica. A convivência do quiabeiro com as plantas daninhas por todo o ciclo de cultivo reduziu a produtividade da cultura em 95%. O período anterior à interferência foi de 57 DAE, enquanto o período total de prevenção à interferência foi de 14 DAE. Não houve período crítico de prevenção à interferência, sendo um único controle das plantas daninhas entre 14 e 57 DAE suficiente para prevenir a interferência na cultura do quiabo.Few research works have been carried out on weed interference in okra crop. The aim of this study was to estimate the periods of weed interference in okra crop. Thus, a field trial was carried out under two groups of treatments, using increased periods of 0 (check, 7, 21, 28, 35, 42, 49, 63, 77, 91, and 105 days after crop emergence (DAE with weed control and without weed control. Weeds with highest relative importance were Portulaca oleracea, Nicandra physaloides, and Eleusine indica. Coexistence of okra crop and weeds throughout the season reduced crop yield by 95%. The period before interference was 57 DAE, while total period of interference prevention was 14 DAE. There was no critical period of interference prevention, with a single weed control between 14 and 57 DAE being sufficient for interference prevention in okra crop.

  8. The Effects of Interfering COX-2 Gene Expression on Malignant Proliferation of Human Lung Adenocarcinoma A2 Cell in vitro

    Directory of Open Access Journals (Sweden)

    Weiying LI

    2009-02-01

    Full Text Available Background and objective COX-2 was highly expressed in many tumor tissues and was involved in the initiation and development of tumors. The RNAi technique is a method to inhibit gene expression economically, quickly, efficiently and specifically. This study used RNAi technique to explore the interfering effect of COX-2 geneexpression and the influence on the malignant proliferation of A2 cells after quenching COX-2 in vitro . Methods Three COX-2 siRNA expression vectors with human U6 promoter were constructed. The COX-2 siRNA vectors and the vacant vector (pEGFP were transfected into A2 cells with lipofectamine respectively. The cell strains transfected were selected. The change of COX-2 expression levels was examined by Western blot and RT-PCR. The effects on the proliferationof A2 cells after silencing COX-2 were detected by cell growth curve and clonogenic assay in vitro . Results The three siRNA and U6 promoter cloned into pEGFP plasmid were validated by PCR, restriction endonucleases identification, DNA sequencing and BLAST alignment. The cell strains transfected were coded as A2-3, A2-7, A2-10 and A2-p respectively. Green fluorescence was seen in A2-p cells and not in A2-3, A2-7 and A2-10 cells in 24 h, 48 h and 72 hafter transfected. The results of RT-PCR and Western blot showed the three siRNA expression vectors acted effectively and the expression of COX-2 was inhibited in different extent. In contrast to A2 cells, COX-2 mRNA levels of A2-3, A2-7 and A2-10 cells were reduced 15.6%, 20.4% and 64.2% respectively, and COX-2 protein expressions of them were reduced 23.7%, 36.7% and 60.2% respectively. The results of cell growth curve and clonogenic assay showed the growth of A2-10 cell slowed and the clonal formation rate was reduced. However the growth of A2-3 and A2-7 cells had no obvious changes vs controls (A2 and A2-p. Conclusion Silencing COX-2 gene in vitro by RNAi technique can significantly inhibit the malignant proliferation of A2

  9. Multiplexed analysis combining distinctly-sized CdTe-MPA quantum dots and chemometrics for multiple mutually interfering analyte determination.

    Science.gov (United States)

    Bittar, Dayana B; Ribeiro, David S M; Páscoa, Ricardo N M J; Soares, José X; Rodrigues, S Sofia M; Castro, Rafael C; Pezza, Leonardo; Pezza, Helena R; Santos, João L M

    2017-11-01

    Semiconductor quantum dots (QDs) have demonstrated a great potential as fluorescent probes for heavy metals monitoring. However, their great reactivity, whose tunability could be difficult to attain, could impair selectivity yielding analytical results with poor accuracy. In this work, the combination in the same analysis of multiple QDs, each with a particular ability to interact with the analyte, assured a multi-point detection that was not only exploited for a more precise analyte discrimination but also for the simultaneous discrimination of multiple mutually interfering species, in the same sample. Three different MPA-CdTe QDs (2.5, 3.0 and 3.8nm) with a good size distribution, confirmed by the FWHM values of 48.6, 55.4 and 80.8nm, respectively, were used. Principal component analysis (PCA) and partial least squares regression (PLS) were used for fluorescence data analysis. Mixtures of two MPA-CdTe QDs, emitting at different wavelength namely 549/566, 549/634 and 566/634nm were assayed. The 549/634nm emitting QDs mixture provided the best results for the discrimination of distinct ions on binary and ternary mixtures. The obtained RMSECV and R 2 CV values for the binary mixture were good, namely, from 0.01 to 0.08mgL -1 and from 0.74 to 0.89, respectively. Regarding the ternary mixture the RMSECV and R 2 CV values were good for Hg(II) (0.06 and 0.73mgL -1 , respectively) and Pb(II) (0.08 and 0.87mg L -1 , respectively) and acceptable for Cu(II) (0.02 and 0.51mgL -1 , respectively). In conclusion, the obtained results showed that the developed approach is capable of resolve binary and ternary mixtures of Pb (II), Hg (II) and Cu (II), providing accurate information about lead (II) and mercury (II) concentration and signaling the occurrence of Cu (II). Copyright © 2017 Elsevier B.V. All rights reserved.

  10. Parallel ClickSeq and Nanopore sequencing elucidates the rapid evolution of defective-interfering RNAs in Flock House virus.

    Directory of Open Access Journals (Sweden)

    Elizabeth Jaworski

    2017-05-01

    Full Text Available Defective-Interfering RNAs (DI-RNAs have long been known to play an important role in virus replication and transmission. DI-RNAs emerge during virus passaging in both cell-culture and their hosts as a result of non-homologous RNA recombination. However, the principles of DI-RNA emergence and their subsequent evolution have remained elusive. Using a combination of long- and short-read Next-Generation Sequencing, we have characterized the formation of DI-RNAs during serial passaging of Flock House virus (FHV in cell-culture over a period of 30 days in order to elucidate the pathways and potential mechanisms of DI-RNA emergence and evolution. For short-read RNAseq, we employed 'ClickSeq' due to its ability to sensitively and confidently detect RNA recombination events with nucleotide resolution. In parallel, we used the Oxford Nanopore Technologies's (ONT MinION to resolve full-length defective and wild-type viral genomes. Together, these accurately resolve both rare and common RNA recombination events, determine the correlation between recombination events, and quantifies the relative abundance of different DI-RNAs throughout passaging. We observe the formation of a diverse pool of defective RNAs at each stage of viral passaging. However, many of these 'intermediate' species, while present in early stages of passaging, do not accumulate. After approximately 9 days of passaging we observe the rapid accumulation of DI-RNAs with a correlated reduction in specific infectivity and with the Nanopore data find that DI-RNAs are characterized by multiple RNA recombination events. This suggests that intermediate DI-RNA species are not competitive and that multiple recombination events interact epistatically to confer 'mature' DI-RNAs with their selective advantage allowing for their rapid accumulation. Alternatively, it is possible that mature DI-RNA species are generated in a single event involving multiple RNA rearrangements. These insights have

  11. Small Composers

    DEFF Research Database (Denmark)

    Holgersen, Sven-Erik; Bruun, Peter; Tjagvad, Mette

    2018-01-01

    The present chapter discusses roles and responsibilities of the collaborating partners in a creative music workshop called Small Composers. The aim is to be attentive to a number of potential alterations implicated by the collaborating partners’ different backgrounds. The following questions guided...... the study: What expectations do the class teacher and the professional musicians have to the creative practice, i.e. to the collaboration and to the musical outcome? To which extent do the collaborating partners share a common understanding of the aim, content and method of the workshop? How do the roles...... and responsibilities of the collaborating partners become visible through the practice? How do the professional identities of the teacher and the musicians become visible and what are the implications for the workshop as a musical community of practice?...

  12. Small talk

    Directory of Open Access Journals (Sweden)

    Ryszard Przybylski

    2016-12-01

    Full Text Available The poem Small talk conjures up a communicative situation in which the main character, a newcomer from Poland, answers conventional questions related to their country. Bearing in mind the fact that this poem is set during a military dictatorship, superficial interest in his homeland may trigger a feeling of impatience. This is at least the impression formed if we adopt the perspective defined within the romantic tradition, and when taking into account the conventional poetry of martial law in Poland. Nevertheless, Barańczak retains an ironic distance towards such communicative situations and, as a consequence, does not create poetry that meets most readersʼ expectations. His poetic imperative for verbal art to be the expression of mistrust remains valid.

  13. Small Composers

    DEFF Research Database (Denmark)

    Holgersen, Sven-Erik; Bruun, Peter; Tjagvad, Mette

    2018-01-01

    The present chapter discusses roles and responsibilities of the collaborating partners in a creative music workshop called Small Composers. The aim is to be attentive to a number of potential alterations implicated by the collaborating partners’ different backgrounds. The following questions guid...... and responsibilities of the collaborating partners become visible through the practice? How do the professional identities of the teacher and the musicians become visible and what are the implications for the workshop as a musical community of practice?...... the study: What expectations do the class teacher and the professional musicians have to the creative practice, i.e. to the collaboration and to the musical outcome? To which extent do the collaborating partners share a common understanding of the aim, content and method of the workshop? How do the roles...

  14. Interferência por RNA: uma nova alternativa para terapia nas doenças reumáticas RNA interference: a new alternative for rheumatic diseases therapy

    Directory of Open Access Journals (Sweden)

    Natália Regine de França

    2010-12-01

    Full Text Available A interferência por RNA (RNAi é um mecanismo de silenciamento gênico pós-transcricional conservado durante a evolução. Esse mecanismo, recentemente descrito, é mediado por pequenos RNAs de fita dupla (dsRNAs capazes de reconhecer especificamente uma sequência de mRNA-alvo e mediar sua clivagem ou repressão traducional. O emprego da RNAi como uma ferramenta de terapia gênica tem sido muito estudado, especialmente em infecções virais, câncer, desordens genéticas herdadas, doenças cardiovasculares e mesmo em doenças reumáticas. Aliados aos dados do genoma humano, os conhecimentos do silenciamento gênico mediado por RNAi podem permitir a determinação funcional de praticamente qualquer gene expresso em uma célula e sua implicação para o funcionamento e homeostase celular. Vários estudos terapêuticos in vitro e in vivo em modelos de doenças autoimunes vêm sendo realizados com resultados encorajadores. As vias de quebra de tolerância e inflamação são alvos potenciais para terapia com RNAi em doenças inflamatórias e autoimunes. Nesta revisão vamos recordar os princípios básicos da RNAi e discutir os aspectos que levaram ao desenvolvimento de propostas terapêuticas baseadas em RNAi, começando pelos estudos in vitro de desenvolvimento de ferramentas e identificação de alvos, chegando até os estudos pré-clínicos de disponibilização da droga in vivo, e testes em células humanas e modelos animais de doenças autoimunes. Por fim, vamos revisar os últimos avanços da experiência clínica da terapia com RNAiRNA interference (RNAi is a post-transcriptional gene silencing mechanism preserved during evolution. This mechanism, recently described, is mediated by small double-stranded RNAs (dsRNAs that can specifically recognize a target mRNA sequence and mediate its cleavage or translational repression. The use of RNAi as a tool for gene therapy has been extensively studied, especially in viral infections, cancer

  15. Construction of small RNA cDNA libraries for deep sequencing.

    Science.gov (United States)

    Lu, Cheng; Meyers, Blake C; Green, Pamela J

    2007-10-01

    Small RNAs (21-24 nucleotides) including microRNAs (miRNAs) and small interfering RNAs (siRNAs) are potent regulators of gene expression in both plants and animals. Several hundred genes encoding miRNAs and thousands of siRNAs have been experimentally identified by cloning approaches. New sequencing technologies facilitate the identification of these molecules and provide global quantitative expression data in a given biological sample. Here, we describe the methods used in our laboratory to construct small RNA cDNA libraries for high-throughput sequencing using technologies such as MPSS, 454 or SBS.

  16. Estudo da interferência de óleos essenciais sobre a atividade de alguns antibióticos usados na clínica

    Directory of Open Access Journals (Sweden)

    Rinalda A. Guerra de Oliveira

    Full Text Available O objetivo deste estudo foi investigar a interferência dos óleos essenciais de Lippia sidoides Cham, Plectranthus amboinicus Lour Spr., Conyza bonariensis L. e Eucalyptus citriodora Hook sobre o efeito de antibióticos utilizados na clínica. Os ensaios foram realizados com ampicilina (10 µg/mL, cefalotina (30 µg/mL, cloranfenicol (30 µg/mL, gentamicina (10 µg/mL e tetraciclina (30 µg/mL isolados e em associação com os óleos essenciais (4% v/v através do método de difusão em meio sólido utilizando discos de papel de filtro. Os resultados mostraram interferência de alguns óleos essenciais sobre a atividade dos antibióticos ensaiados. Observou-se o desenvolvimento de halos de inibição do crescimento bacteriano com diferentes diâmetros quando da aplicação de antibióticos isolados e em combinação com os óleos essenciais. A ocorrência de comportamento sinérgico ou antagônico foi observada mais proeminentemente nas interações com cepas de S. aureus e S. epidermidis. De outra forma, observou-se uma menor interferência dos óleos essenciais no efeito dos antibióticos sobre as cepas Gram negativas, principalmente P. aeruginosa. Estes resultados mostram que o uso de produtos derivados de plantas pode em algumas situações interferir sobre a efetividade de antibióticos de uso no tratamento clínico.

  17. Estudo de revisão sobre a interferência de hipoglicemiantes orais no exame químico de urina

    Directory of Open Access Journals (Sweden)

    Carolina Machado Ramos

    2016-07-01

    Full Text Available A diabetes mellitus (DM é uma doença que vem aumentando exponencialmente nos últimos anos de vida dos indivíduos, e uma opção de tratamento farmacológico é feito através dos hipoglicemiantes orais (HO. Em virtude de serem substâncias amplamente utilizadas e terem como principal via de excreção a urinária, este tratamento pode provocar variações nos resultados dos parâmetros urinários. Portanto, este estudo tem a finalidade de avaliar a interferência causada pelo uso de hipoglicemiantes no exame de urina. Para esta investigação, foi feita uma pesquisa bibliográfica em diferentes bases de dados, selecionando os artigos pertinentes ao tema: diabetes, interferências laboratoriais e tratamento farmacológico. Os HO podem ser classificados em três grupos de acordo com o mecanismo de ação: estimuladores de insulinas pelo pâncreas, como sulfoniluréias e metiglinidas; as sensibilizadoras de insulina, são as biguanidas, as tiazolidinedionas e as redutoras da absorção de carboidratos, que são as inibidoras da alfa-glicosidase. O exame de urina é uma ferramenta complementar no controle da DM devido a sua fácil coleta e baixo custo. As classes de hipoglicemiantes orais identificados como potencialmente interferentes no exame de urina foram as biguanidas (metformina e as sulfoniluréias (tobultamida, tolazamida, glicazida, clorpropramida. Resultam em interferência nos parâmetros densidade, proteínas, glicose, cetonas e bilirrubinas, levando a um diagnóstico inadequado e um tratamento insatisfatório gerando prejuízos ao bem estar do paciente.

  18. Impact of wastewater derived dissolved interfering compounds on growth, enzymatic activity and trace organic contaminant removal of white rot fungi - A critical review.

    Science.gov (United States)

    Asif, Muhammad B; Hai, Faisal I; Hou, Jingwei; Price, William E; Nghiem, Long D

    2017-10-01

    White-rot fungi (WRF) and their ligninolytic enzymes have been investigated for the removal of a broad spectrum of trace organic contaminants (TrOCs) mostly from synthetic wastewater in lab-scale experiments. Only a few studies have reported the efficiency of such systems for the removal of TrOCs from real wastewater. Wastewater derived organic and inorganic compounds can inhibit: (i) WRF growth and their enzyme production capacity; (ii) enzymatic activity of ligninolytic enzymes; and (iii) catalytic efficiency of both WRF and enzymes. It is observed that essential metals such as Cu, Mn and Co at trace concertation (up to 1 mM) can improve the growth of WRF species, whereas non-essential metal such as Pb, Cd and Hg at 1 mM concentration can inhibit WRF growth and their enzyme production. In the case of purified enzymes, most of the tested metals at 1-5 mM concentration do not significantly inhibit the activity of laccases. Organic interfering compounds such as oxalic acid and ethylenediaminetetraacetic acid (EDTA) at 1 mM concentration are potent inhibitors of WRF and their extracellular enzymes. However, inhibitory effects induced by interfering compounds are strongly influenced by the type of WRF species as well as experimental conditions (e.g., incubation time and TrOC type). In this review, mechanisms and factors governing the interactions of interfering compounds with WRF and their ligninolytic enzymes are reviewed and elucidated. In addition, the performance of WRF and their ligninolytic enzymes for the removal of TrOCs from synthetic and real wastewater is critically summarized. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Costo-efectividad del tratamiento con interferón beta en pacientes con síndrome clínico aislado de alto riesgo en Colombia

    Directory of Open Access Journals (Sweden)

    Luis Alfonso Zarco

    2014-03-01

    Full Text Available Introducción. En 85 % de los pacientes con esclerosis múltiple se presenta como manifestación inicial un primer evento desmielinizante o síndrome clínico aislado. En estos casos, el tratamiento con interferón beta retrasa hasta dos años la progresión a esclerosis múltiple. Sin embargo, en Colombia este medicamento es costoso. Objetivo. Determinar si el tratamiento del síndrome clínico aislado con interferón beta es costo-efectivo al retrasar la esclerosis múltiple en dos años. Materiales y métodos. Se realizó un análisis de costo-efectividad empleando un árbol de decisiones basado en la perspectiva del paciente y la sociedad. A partir de una revisión sistemática de la literatura y de conceptos de expertos se definieron las diversas probabilidades. Los costos de la enfermedad se calcularon por medio de la revisión de historias y la aplicación de encuestas a los pacientes atendidos en el Hospital Universitario San Ignacio. Para controlar la incertidumbre se realizó un análisis de sensibilidad mediante una simulación de Monte Carlo con mil pacientes. Resultados. El costo del tratamiento con interferón sobrepasa los Col$ 95’000.000 (US$ 50.000 por paciente durante los dos años. Aproximadamente, 80 % corresponde a los costos del medicamento. El costo de la recaída se acerca a Col$ 39’139.200 (US$ 21.744, y los costos indirectos corresponden a Col$ 10’958.400 (US$ 6.088. La tasa representativa del mercado fue de Col$ 1.800. Con el tratamiento se ganan sólo 0,06 años de vida ajustados por discapacidad (AVAD adicionales. La razón de costo-efectividad ‘incremental’ (sic. supera el umbral, incluso en el análisis de sensibilidad. Conclusión. La administración de interferón beta en pacientes con síndrome clínico aislado de alto riesgo en los primeros dos años no es costo-efectiva en Colombia.

  20. Interfering elements in activation analysis. Study of instrumental analysis possibilities for the groups: Sc-Zn, Hg-Se and As-Sb-Br

    International Nuclear Information System (INIS)

    Figueiredo, A.M.G.; Atalla, L.T.

    1979-01-01

    The determination of the elements present in the groups Sc-Zn, Hg-Se and As-Sb-Br represents a classical problem in thermal neutron activation analysis, since the energy values of the gamma-ray photopeaks of the radioisotopes of these elements formed by thermal neutron activation are very closely located in the spectrum. A study is presented of the possibility of simultaneous instrumental determination of these elements by means of the spectrum stripping technique. For this purpose, artificial mixtures of the interfering elements, in varying proportions, were prepared. Radiochemical separations procedures for the above mentioned elements were also studied by means of tracers. (Author) [pt

  1. Determinación paramétrica de los ejes de rotación de las articulaciones interfalángicas de los dedos

    OpenAIRE

    Jarque Bou, Néstor; Sancho-Bru, Joaquin L.; Vergara Monedero, Margarita; Pérez González, Antonio; Roda Sales, Alba; Mestre Vicent, S.

    2016-01-01

    Comunicación presentada en el XXI Congreso Nacional de Ingeniería Mecánica, celebrado en Elche en Noviembre de 2016. Los ejes de rotación de las articulaciones interfalángicas de los dedos son aproximadamente paralelos a los pliegues de flexión. Sin embargo, los modelos biomecánicos y ergonómicos existentes suelen considerar ejes de rotación paralelos entre sí y perpendiculares a los ejes longitudinales de las falanges. Recientemente se han utilizado técnicas de resonancia magnéti...

  2. Small Sar Satellite Using Small Standard Bus

    OpenAIRE

    Ono, Kiyonobu; Fujimura, Takashi; Ogawa, Toshiaki; Kimura, Tsunekazu

    2011-01-01

    This paper introduces a new small SAR (Synthetic Aperture Radar) satellite that follows the small optical sensor satellite, ASNARO. USEF, NEDO and NEC are developing ASNARO satellite, which is a small LEO satellite (total mass

  3. Extending the inverse scattering series free-surface-multiple-elimination algorithm by accommodating the source property on data with interfering or proximal seismic events

    Science.gov (United States)

    Zhao, Lei; Yang, Jinlong; Weglein, Arthur B.

    2017-12-01

    The inverse scattering series free-surface-multiple-elimination (FSME) algorithm is modified and extended to accommodate the source property-source radiation pattern. That accommodation can provide additional value for the fidelity of the free-surface multiple predictions. The new extended FSME algorithm retains all the merits of the original algorithm, i.e., fully data-driven and with a requirement of no subsurface information. It is tested on a one-dimensional acoustic model with proximal and interfering seismic events, such as interfering primaries and multiples. The results indicate the new extended FSME algorithm can predict more accurate free-surface multiples than methods without the accommodation of the source property if the source has a radiation pattern. This increased effectiveness in prediction contributes to removing free-surface multiples without damaging primaries. It is important in such cases to increase predictive effectiveness because other prediction methods, such as the surface-related-multiple-elimination algorithm, has difficulties and problems in prediction accuracy, and those issues affect efforts to remove multiples through adaptive subtraction. Therefore accommodation of the source property can not only improve the effectiveness of the FSME algorithm, but also extend the method beyond the current algorithm (e.g. improving the internal multiple attenuation algorithm).

  4. Chemometrics-assisted high performance liquid chromatography-diode array detection strategy to solve varying interfering patterns from different chromatographic columns and sample matrices for beverage analysis.

    Science.gov (United States)

    Yin, Xiao-Li; Wu, Hai-Long; Gu, Hui-Wen; Hu, Yong; Wang, Li; Xia, Hui; Xiang, Shou-Xia; Yu, Ru-Qin

    2016-02-26

    This work reports a chemometrics-assisted high performance liquid chromatography-diode array detection (HPLC-DAD) strategy to solve varying interfering patterns from different chromatographic columns and sample matrices for the rapid simultaneous determination of six synthetic colorants in five kinds of beverages with little sample pretreatment. The investigation was performed using two types of LC columns under the same elution conditions. Although analytes using different columns have different co-elution patterns that appear more seriously in complex backgrounds, all colorants were properly resolved by alternating trilinear decomposition (ATLD) method and accurate chromatographic elution profiles, spectral profiles as well as relative concentrations were obtained. The results were confirmed by those obtained from traditional HPLC-UV method at a particular wavelength and the results of both methods were consistent with each other. All results demonstrated that the proposed chemometrics-assisted HPLC-DAD method is accurate, economical and universal, and can be promisingly applied to solve varying interfering patterns from different chromatographic columns and sample matrices for the analysis of complex food samples. Copyright © 2016 Elsevier B.V. All rights reserved.

  5. The slicer activity of ARGONAUTE1 is required specifically for the phasing, not production, of trans-acting short interfering RNAs in Arabidopsis

    DEFF Research Database (Denmark)

    Arribas Hernandez, Laura; Marchais, Antonin; Poulsen, Christian

    2016-01-01

    ARGONAUTE1 (AGO1) mediates posttranscriptional silencing by microRNAs (miRNAs) and short interfering RNAS (siRNAs). AGO1-catalyzed RNA cleavage (slicing) represses miRNA targets, but current models also highlight the roles of slicing in formation of siRNAs and siRNA-AGO1 complexes. miRNA-guided s......ARGONAUTE1 (AGO1) mediates posttranscriptional silencing by microRNAs (miRNAs) and short interfering RNAS (siRNAs). AGO1-catalyzed RNA cleavage (slicing) represses miRNA targets, but current models also highlight the roles of slicing in formation of siRNAs and siRNA-AGO1 complexes. mi...... is required for assembly of active AGO1-siRNA complexes in vivo, and many AGO1-bound siRNAs are trimmed in the absence of slicer activity. Remarkably, seedlings defective in AGO1 slicer activity produce abundant siRNAs from tasiRNA loci in vivo. These siRNAs depend on RDR6 and SUPPRESSOR OF GENE SILENCING3...

  6. Performance Evaluation of Electro-Fenton Process (EFP in Removal of Hexavalent Chromium in the Presence of Cyanide, as an Interfering Agent, from Synthetic Wastewaters

    Directory of Open Access Journals (Sweden)

    Ali Reza Rahmani

    2014-06-01

    Full Text Available Background: Chromium (VI is a hazardous pollutant that enters into the environment through different industrial wastewater. Therefore, Choice a suitable method for removal of the pollutant before discharging into the environment is necessary. The aim of this work was performance evaluation of Electro-Fenton process (EFP in removal of hexavalent chromium in the presence of cyanide, as an interfering agent, from synthetic wastewaters. Methods: In this experimental study, a reactor with 1 L useful volume and 4 electrodes made ​​of iron was used. pH, initial concentration of  chromium (VI, voltage, hydrogen peroxide and cyanide concentration, as an interfering agent, were investigated in order to determine the process efficiency. Results: Results reveals that the considered parameters were affected on the efficiency of the process. In optimum condition, pH=3 and voltage=20 V, initial concentration=100 mg/L, concentration of hydrogen peroxide=50 mL/L the maximum efficiency was reached up to 97%. Cyanide Presence, in the same condition, reduced the efficiency under 50 % and also, the efficiency was decreased by changing the parameters level from optimum condition. Conclusion: Results indicate the proper efficiency of chromium (VI by EFP process; however presence of other pollutants such as cyanide can cause efficiency decrease which must be considered in the process application.

  7. Reconstrução do ligamento cruzado anterior com tendões flexores quadrúplos e parafusos de interferências metálicos.

    Directory of Open Access Journals (Sweden)

    Julio Cesar Gali

    2007-05-01

    Full Text Available Existem muitas técnicas de reconstrução cirúrgica do ligamento cruzado anterior, utilizando diferentes tipos de enxertos e variados métodos de fixação. O objetivo deste trabalho é apresentar os resultados da reconstrução do ligamento cruzado anterior com enxerto quádruplo de tendões do semitendíneo e grácil, fixado com parafuso de interferência metálico em 64 casos, segundo o protocolo do Internacional Knee Documentation Committee. A idade dos pacientes variou de 14 a 46 anos (média de 30,9 e o seguimento variou entre 12 e 38 meses (média de 21,5. Na avaliação final, os joelhos de 95% dos pacientes foram graduados como normais ou próximos ao normal. A técnica é mais uma opção para reconstrução do ligamento, e os parafusos de interferência metálicos podem produzir fixação anatômica a custo acessível.

  8. Períodos de interferência das plantas daninhas em algodoeiro de fibra colorida 'BRS Safira' Weeds interference periods in naturally colored cotton 'BRS Safira'

    Directory of Open Access Journals (Sweden)

    Gleibson Dionízio Cardoso

    2010-09-01

    Full Text Available Objetivou-se com esse trabalho, identificar os períodos de interferência das plantas daninhas no algodoeiro de fibra colorida (BRS Safira, bem como avaliar a comunidade infestante nesta cultura. O experimento foi realizado no município de Missão Velha, CE, região do Cariri, na safra 2007/2008. Utilizou-se o delineamento experimental em blocos ao acaso, com quatro repetições, em esquema fatorial 2 x 5, sendo os fatores: modalidades de competição (com e sem competição de plantas daninhas e período de interferência das plantas daninhas. A comunidade infestante foi avaliada por meio de dois índices fitossociológicos (Dominância relativa e Importância relativa. Os períodos iniciais de controle ou de convivência após a emergência da cultura foram 0-20; 0-40; 0-60; 0-80 dias após a emergência (DAE e 0-colheita. Os períodos de interferência foram determinados considerando-se perdas na produtividade de 2; 5 e 10%; realizando-se análise de regressão pelo modelo sigmoidal de Boltzman, utilizando-se os dados de produtividade para cada modalidade de competição. Dentre as 21 espécies observadas na comunidade infestante, destacaram-se: Richardia grandiflora, Amaranthus deflexus, Eleusine indica, Merremia aegyptia, Eragrotis pilosa, Cenchrus echinatus e Waltheria indica. Os períodos críticos anteriores à interferência foram, respectivamente, 8; 14 e 20 DAE, para perdas na produtividade de 2; 5 e 10%; e os períodos críticos de prevenção a interferências, foram, respectivamente, 100; 82 e 60 dias.This study aimed to determine the late-season presence of weeds in reddish brown cotton (cultivar BRS Safira and the critical times for removing weeds. The experiment was carried out in the area of Embrapa in Missão Velha-CE, Brazil, located at 7º42'07" S latitude and 39º24'18" WGr. longitude, during the 2007/2008 season. The treatments consisted of two control groups: weed-free crop during the initial period after crop emergency

  9. Small Business Development Center

    Data.gov (United States)

    Small Business Administration — Small Business Development Centers (SBDCs) provide assistance to small businesses and aspiring entrepreneurs throughout the United States and its territories. SBDCs...

  10. Hepatitis C virus non-structural 5B protein interacts with cyclin A2 and regulates viral propagation

    DEFF Research Database (Denmark)

    Pham, Long; Ngo, HT; Lim, YS

    2012-01-01

    Background & Aims Hepatitis C virus (HCV) requires host cellular proteins for its own propagation. To identify the cellular factors necessary for HCV propagation, we have recently screened the small interfering RNA (siRNA) library targeting cell cycle genes using cell culture grown HCV (HCVcc......, in vitro and in vivo protein binding assays, luciferase reporter gene assay, and immunoblot assay. Results We showed that siRNA-mediated depletion of CycA2 significantly inhibited HCV replication in both HCV subgenomic replicon cells and HCVcc-infected cells. Furthermore, HCV non-structural 5B (NS5B......)-infected cells. In the current study, we have selected and characterized the gene encoding Cyclin A2 (CycA2). Deregulation of CycA2 has been implicated in many types of cancers, including hepatocellular carcinoma. Methods The effects of CycA2 on HCV propagation were investigated by siRNA-mediated knockdown assay...

  11. Seguridad de la terapia de interferón alfa 2b recombinante más ribavirina en la hepatitis crónica C

    Directory of Open Access Journals (Sweden)

    Yoan Antonio Sánchez Rodríguez

    2011-03-01

    Full Text Available INTRODUCCIÓN: la hepatitis crónica C ha adquirido rango de pandemia. El virus de la hepatitis C se ha convertido en la causa principal de hepatitis crónica, cirrosis hepática, hepatocarcinoma, y trasplante de hígado a nivel mundial. OBJETIVO: identificar los efectos adversos asociados a la terapia combinada interferón alfa 2b recombinante más ribavirina durante la evolución del tratamiento y hasta 8 semanas después de finalizado, así como los principales efectos asociados a salidas temporales o definitivas de esta terapia. MÉTODOS: estudio de farmacovigilancia cuya serie estuvo conformada por 122 pacientes con hepatitis crónica C atendidos en el Instituto de Gastroenterología desde mayo de 2001 hasta mayo de 2006. Se utilizó interferón alfa 2b recombinante (3 millones de unidades 3 veces por semana más ribavirina (1 000 o 1 200 mg diarios en dependencia del peso corporal durante 48 semanas. RESULTADOS: el 88,5 % del total de casos presentó efectos adversos; de ellos el 79,5 % correspondió al síndrome seudogripal, seguido de manifestaciones hematológicas, neuropsiquiátricas, gastrointestinales, entre otras menos frecuentes. El 6,6 % de la serie presentó salidas temporales del tratamiento por efecto adverso distinto de la anemia y 4 pacientes, salidas definitivas del estudio, tres por anemia hemolítica severa y uno con hipertiroidismo no controlable. CONCLUSIONES: la terapia combinada interferón alfa 2b recombinante más ribavirina resulta segura, donde el mayor número de casos presentó síndrome seudogripal como efecto adverso más frecuente. Las manifestaciones hematológicas asociadas a las salidas definitivas del estudio permitieron recomendar seguimiento estricto de la hemoglobina y profundizar en el diagnóstico y tratamiento de los principales efectos adversos presentes en otros sistemas y asociados a esta terapia.

  12. Interferência de ferro na dosagem de boro no solo com azometina-H em soluções extratoras ácidas

    Directory of Open Access Journals (Sweden)

    Ferreira Gilvan Barbosa

    2002-01-01

    Full Text Available A busca de métodos que permitam a extração do boro para avaliação da fertilidade do solo para a recomendação de adubação é importante, devido aos baixos teores de boro e aos altos teores de Fe na maioria dos solos brasileiros. A extração com água quente, método-referência, é trabalhosa e apresenta dificuldades operacionais. Por outro lado, soluções de CaCl2 5 mmol/L e BaCl2.2H2O 5 mmol/L são usadas com sucesso. O objetivo deste trabalho foi testar a eficiência do ácido tioglicólico na eliminação da interferência do Fe na dosagem de B do solo com azometina-H, após extrações com soluções ácidas de Mehlich-1 e HCl (50 e 100 mmol/L. Dosagem com azometina-H, com e sem ácido tioglicólico, foram feitas para oito solos de Minas Gerais e dois solos do Mato Grosso do Sul. Foi utilizada como referência, a extração com BaCl2.2H2O 5 mmol/L, com aquecimento em forno de microondas e dosagem com azometina-H; a determinação de B com azometina-H em extratos originados de soluções ácidas sofre forte interferência do Fe. A adição do ácido tioglicólico não remove esta interferência. A coloração do complexo B-azometina-H fica menos estável com a adição do ácido tioglicólico na dosagem do boro.

  13. Possível interferência da antitoxina tetânica pré-existente, na vacinação antitetânica Possible interference of pre-existing tetanus antitoxin in antitetanus immunization

    Directory of Open Access Journals (Sweden)

    Rosalvo Guidolin

    1981-04-01

    Full Text Available Estudou-se qual a possível interferência no desenvolvimento da imunidade antitetânica ativa em cobaias e camundongos, filhos de fêmeas vacinadas contra o tétano em diferentes épocas durante o período da prenhês. Verificou-se que a vacinação das fêmeas, em gestação não interferiu, negativamente, no desenvolvimento da imunidade ativa dos animais filhos, quando submetidos à vacinação ao redor de 60 dias após o nascimento. A presença de baixos níveis de anticorpos circulantes, recebidos congenitamente, parece ter, em determinadas condições, estimulado a resposta imunitária quando, posteriormente, os animais filhos foram vacinados contra o tétano. Sugere-se que o complexo antígeno-anticorpo formado seja capaz de melhorar a resposta imunitária induzida pelo toxóide.Possibility of interference in the development of active antitetanic immunity was studied in the offspring of guinea pigs and mice whose mothers had received antitetanic vaccine during different periods of pregnancy. Vaccination of the females during pregnancy did not interfere negatively in the development of active immunity in their offspring when the latter were vaccinated about 60 days after birth. The presence of small amounts of circulating antibodies, congenitally received, seems, under certain conditions, to stimulate the immune response upon posterior vaccination against tetanus. This suggests that the acquired antigen-antibody complex heightens the immune response induced by the toxoid.

  14. Endogenous Small RNA Clusters in Plants

    Directory of Open Access Journals (Sweden)

    Yong-Xin Liu

    2014-04-01

    Full Text Available In plants, small RNAs (sRNAs usually refer to non-coding RNAs (ncRNAs with lengths of 20–24 nucleotides. sRNAs are involved in the regulation of many essential processes related to plant development and environmental responses. sRNAs in plants are mainly grouped into microRNAs (miRNAs and small interfering RNAs (siRNAs, and the latter can be further classified into trans-acting siRNAs (ta-siRNAs, repeat-associated siRNAs (ra-siRNAs, natural anti-sense siRNAs (nat-siRNAs, etc. Many sRNAs exhibit a clustered distribution pattern in the genome. Here, we summarize the features and functions of cluster-distributed sRNAs, aimed to not only provide a thorough picture of sRNA clusters (SRCs in plants, but also shed light on the identification of new classes of functional sRNAs.

  15. Incorporation of dietary fibre-rich oyster mushroom (Pleurotus sajor-caju) powder improves postprandial glycaemic response by interfering with starch granule structure and starch digestibility of biscuit.

    Science.gov (United States)

    Ng, Sze Han; Robert, Sathyasurya Daniel; Wan Ahmad, Wan Amir Nizam; Wan Ishak, Wan Rosli

    2017-07-15

    The purpose of this study was to determine the effects of Pleurotus sajor-caju (PSC) powder addition at 0, 4, 8 and 12% levels on the nutritional values, pasting properties, thermal characteristics, microstructure, in vitro starch digestibility, in vivo glycaemic index (GI) and sensorial properties of biscuits. Elevated incorporation levels of PSC powder increased the dietary fibre (DF) content and reduced the pasting viscosities and starch gelatinisation enthalpy value of biscuits. The addition of DF-rich PSC powder also interfered with the integrity of the starch granules by reducing the sizes and inducing the uneven spherical shapes of the starch granules, which, in turn, resulted in reduced starch susceptibility to digestive enzymes. The restriction starch hydrolysis rate markedly reduced the GI of biscuits. The incorporation of 8% PSC powder in biscuits (GI=49) could be an effective way of developing a nutritious and low-GI biscuit without jeopardizing its desirable sensorial properties. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Interferência do ácido ascórbico na dosagem glicêmica - doi: 10.5102/ucs.v6i2.722

    OpenAIRE

    Aline Cardoso Barbosa; Tania Cristina Andrade

    2009-01-01

    Sabe-se que exames laboratoriais estão sujeitos a fatores interferentes. A literatura científica cita interferência do ácido ascórbico em dosagens que envolvam oxirredução, como a glicêmica. Devido a isto, buscou-se avaliar o efeito do ácido ascórbico sobre a dosagem glicêmica em dois tipos de soro controle submetidos a diferentes concentrações de ácido ascórbico, variando de 2,5 a 100 mg/dL. Utilizou-se um soro controle com valores normais de glicemia e outro com valores patológicos. Observo...

  17. Rapid de novo generation of defective interfering RNA by cucumber necrosis virus mutants that do not express the 20-kDa nonstructural protein.

    Science.gov (United States)

    Rochon, D M

    1991-01-01

    It is generally believed that serial passage at high multiplicity of infection (moi) is required for the generation of defective interfering (DI) particles. High levels of DI RNAs are found associated with persistent infections initiated with laboratory cultures of cucumber necrosis virus (CNV). Two synthetic CNV transcripts that were derived through site-directed mutagenesis of a highly infectious CNV cDNA clone and that do not express the CNV 20-kDa nonstructural protein were found to generate high levels of symptom-attenuating DI RNAs de novo without serial high-moi passage in transcript-inoculated plants. Such de novo generation of DI RNAs did not occur in infections initiated with wild-type transcript until at least eight serial high-moi passages. The observation that a CNV nonstructural protein mutant rapidly generates DI RNA de novo may provide insight into mechanisms that underly DI particle formation in RNA viruses in general. Images PMID:1722320

  18. Antiviral resistance due to deletion in the neuraminidase gene and defective interfering-like viral polymerase basic 2 RNA of influenza A virus subtype H3N2

    DEFF Research Database (Denmark)

    Trebbien, Ramona; Christiansen, Claus Bohn; Fischer, Thea Kølsen

    2018-01-01

    Background and objective: Antiviral treatment of influenza virus infections can lead to drug resistance of virus. This study investigates a selection of mutations in the full genome of H3N2 influenza A virus isolated from a patient in treatment with oseltamivir. Study design: Respiratory samples...... from a patient were collected before, during, and after antiviral treatment. Whole genome sequencing of the influenza virus by next generation sequencing, and low-frequency-variant analysis was performed. Neuraminidase-inhibition tests were performed with oseltamivir and zanamivir, and viruses were......, indicating a potential risk for transmission of the deleted virus. Full genome deep sequencing was useful to reveal variant mutations that might be selected due to antiviral treatment, and defective interfering-like viral PB2 RNA in the respiratory samples was detected....

  19. Small RNAs in plants: Recent development and application for crop improvement

    OpenAIRE

    Ayushi eKamthan; Abira eChaudhuri; Mohan eKamthan; Asis eDatta

    2015-01-01

    The phenomenon of RNA interference (RNAi) which involves sequence-specific gene regulation by small non-coding RNAs, i.e., small interfering RNA (siRNA) and microRNA (miRNA) has emerged as one of most powerful approaches for crop improvement. RNAi based on siRNA is one of the widely used tools of reverse genetics which aid in revealing gene functions in many species. This technology has been extensively applied to alter the gene expression in plants with an aim to achieve desirable traits. RN...

  20. Dynamique et interférence de paquets d'ondes dans les atomes et dimères d'alcalins

    Science.gov (United States)

    Bouchene, M. A.

    2002-11-01

    (saturation regime, chirped pulse, ...) that allow us to determine the advantages and limits of this technique. In the case of molecules, the interaction of the two-pulse sequence leads to the interference of vibrational wave packets. We analyse and discuss in this case the effects of a thermal distribution of initial states on the temporal coherent control signal. Ce travail porte sur l'étude expérimentale résolue en temps de la dynamique atomique et moléculaire prenant place sur une échelle de temps femtoseconde. Il présente deux orientations distinctes et complémentaires. La première concerne l'étude de la dynamique de paquets d'ondes dans des atomes et dimères d'alcalins (K, K2) par des méthodes pompe-sonde. Dans le cas du potassium atomique le paquet d'ondes est une superposition des états de structure fine de l'état 4p et représente un paquet de spin électronique. Nous observons la dynamique de ce paquet d'ondes au cours du temps et montrons que celle-ci correspond à une inversion du sens d'orientation du spin. Le formalisme théorique des états brillants et noirs est particulièrement adapté à la description de ce type de dynamique. Nous présentons alors une méthode originale qui, tirant avantage du mouvement d'inversion du spin, permet de produire des électrons polarisés en spin à l'échelle femtoseconde. Dans le cas des molécules, le paquet d'ondes créé est une superposition d'états vibrationnels. Nous présentons les résultats d'une étude systématique de la dynamique de paquet d'ondes vibrationnel dans les états électroniques A^1Σ^+_u et 2^1Pi_g. Le signal pompe-sonde dépend alors de la compétition entre les dynamiques associées aux paquets d'ondes créés dans les deux états électroniques. La deuxième partie traite d'expériences d'interférences de paquets d'ondes dans des systèmes similaires (K, Cs, Cs2). Cette technique, complémentaire de la première, consiste à faire interagir une séquence de deux impulsions

  1. Deep sequencing uncovers numerous small RNAs on all four replicons of the plant pathogen Agrobacterium tumefaciens

    Science.gov (United States)

    Wilms, Ina; Overlöper, Aaron; Nowrousian, Minou; Sharma, Cynthia M.; Narberhaus, Franz

    2012-01-01

    Agrobacterium species are capable of interkingdom gene transfer between bacteria and plants. The genome of Agrobacterium tumefaciens consists of a circular and a linear chromosome, the At-plasmid and the Ti-plasmid, which harbors bacterial virulence genes required for tumor formation in plants. Little is known about promoter sequences and the small RNA (sRNA) repertoire of this and other α-proteobacteria. We used a differential RNA sequencing (dRNA-seq) approach to map transcriptional start sites of 388 annotated genes and operons. In addition, a total number of 228 sRNAs was revealed from all four Agrobacterium replicons. Twenty-two of these were confirmed by independent RNA gel blot analysis and several sRNAs were differentially expressed in response to growth media, growth phase, temperature or pH. One sRNA from the Ti-plasmid was massively induced under virulence conditions. The presence of 76 cis-antisense sRNAs, two of them on the reverse strand of virulence genes, suggests considerable antisense transcription in Agrobacterium. The information gained from this study provides a valuable reservoir for an in-depth understanding of sRNA-mediated regulation of the complex physiology and infection process of Agrobacterium. PMID:22336765

  2. Modulation of Autophagy by a Small Molecule Inverse Agonist of ERRα Is Neuroprotective

    Directory of Open Access Journals (Sweden)

    S. N. Suresh

    2018-04-01

    Full Text Available Mechanistic insights into aggrephagy, a selective basal autophagy process to clear misfolded protein aggregates, are lacking. Here, we report and describe the role of Estrogen Related Receptor α (ERRα, HUGO Gene Nomenclature ESRRA, new molecular player of aggrephagy, in keeping autophagy flux in check by inhibiting autophagosome formation. A screen for small molecule modulators for aggrephagy identified ERRα inverse agonist XCT 790, that cleared α-synuclein aggregates in an autophagy dependent, but mammalian target of rapamycin (MTOR independent manner. XCT 790 modulates autophagosome formation in an ERRα dependent manner as validated by siRNA mediated knockdown and over expression approaches. We show that, in a basal state, ERRα is localized on to the autophagosomes and upon autophagy induction by XCT 790, this localization is lost and is accompanied with an increase in autophagosome biogenesis. In a preclinical mouse model of Parkinson’s disease (PD, XCT 790 exerted neuroprotective effects in the dopaminergic neurons of nigra by inducing autophagy to clear toxic protein aggregates and, in addition, ameliorated motor co-ordination deficits. Using a chemical biology approach, we unrevealed the role of ERRα in regulating autophagy and can be therapeutic target for neurodegeneration.

  3. Small Scale Organic Techniques

    Science.gov (United States)

    Horak, V.; Crist, DeLanson R.

    1975-01-01

    Discusses the advantages of using small scale experimentation in the undergraduate organic chemistry laboratory. Describes small scale filtration techniques as an example of a semi-micro method applied to small quantities of material. (MLH)

  4. Lung cancer - small cell

    Science.gov (United States)

    Cancer - lung - small cell; Small cell lung cancer; SCLC ... About 15% of all lung cancer cases are SCLC. Small cell lung cancer is slightly more common in men than women. Almost all cases of SCLC are ...

  5. The application of RNAi-based treatments for inflammatory bowel disease

    DEFF Research Database (Denmark)

    Olesen, Morten Tobias Jarlstad; Gonzalez, Borja Ballarin; Howard, Ken

    2014-01-01

    Inflammatory bowel disease (IBD) is a chronic, relapsing, idiopathic inflammation of the gastrointestinal tract with no permanent cure. Present immunosuppressive and anti-inflammatory therapies are often ineffective and associated with severe side effects. An RNA interference (RNAi)-based approach...... in which small interfering RNA (siRNA) mediates specific downregulation of key molecular targets of the IBD inflammatory process may offer a precise, potent and safer alternative to conventional treatments. This review describes the aetiology of Crohn’s disease and ulcerative colitis and the cellular...

  6. Systems with small dissipation

    CERN Document Server

    Braginsky, V B; Panov, V I

    1985-01-01

    Introduction ; mechanical oscillators with small dissipation ; electromagnetic resonators with small dissipation ; high-quality electromagnetic resonators in physical experiments ; mechanical oscillators in physical experiments

  7. Small Business Size Standards

    Data.gov (United States)

    Small Business Administration — Certain government programs, such as SBA loan programs and contracting opportunities, are reserved for small business concerns. In order to qualify, businesses must...

  8. psRNATarget: a plant small RNA target analysis server.

    Science.gov (United States)

    Dai, Xinbin; Zhao, Patrick Xuechun

    2011-07-01

    Plant endogenous non-coding short small RNAs (20-24 nt), including microRNAs (miRNAs) and a subset of small interfering RNAs (ta-siRNAs), play important role in gene expression regulatory networks (GRNs). For example, many transcription factors and development-related genes have been reported as targets of these regulatory small RNAs. Although a number of miRNA target prediction algorithms and programs have been developed, most of them were designed for animal miRNAs which are significantly different from plant miRNAs in the target recognition process. These differences demand the development of separate plant miRNA (and ta-siRNA) target analysis tool(s). We present psRNATarget, a plant small RNA target analysis server, which features two important analysis functions: (i) reverse complementary matching between small RNA and target transcript using a proven scoring schema, and (ii) target-site accessibility evaluation by calculating unpaired energy (UPE) required to 'open' secondary structure around small RNA's target site on mRNA. The psRNATarget incorporates recent discoveries in plant miRNA target recognition, e.g. it distinguishes translational and post-transcriptional inhibition, and it reports the number of small RNA/target site pairs that may affect small RNA binding activity to target transcript. The psRNATarget server is designed for high-throughput analysis of next-generation data with an efficient distributed computing back-end pipeline that runs on a Linux cluster. The server front-end integrates three simplified user-friendly interfaces to accept user-submitted or preloaded small RNAs and transcript sequences; and outputs a comprehensive list of small RNA/target pairs along with the online tools for batch downloading, key word searching and results sorting. The psRNATarget server is freely available at http://plantgrn.noble.org/psRNATarget/.

  9. Interferência de Euphorbia heterophylla no crescimento e acúmulo de macronutrientes da soja Interference of Euphorbia heterophylla in the growth and macronutrient accumulation of soybean

    Directory of Open Access Journals (Sweden)

    L.B. Carvalho

    2010-01-01

    Full Text Available O grau de interferência depende da densidade de plantas daninhas que infestam a soja. O objetivo deste trabalho foi avaliar características de crescimento e nutrição mineral da soja mantida em convivência com densidades crescentes de Euphorbia heterophylla. O experimento foi conduzido em Jaboticabal, SP, Brasil, entre outubro e dezembro de 2008, em vasos mantidos em campo aberto. Os tratamentos consistiram em submeter uma planta de soja por vaso à convivência com 0, 1, 2, 4, 8 e 16 plantas de E. heterophylla por vaso, da semeadura até o início do florescimento. Nesse período, avaliaram-se, apenas na soja, a altura e o número de trifólios, e em ambas as espécies, a matéria seca e o acúmulo de macronutrientes. Observou-se variação na altura de plantas e redução no número de trifólios e no acúmulo de matéria seca e macronutrientes da soja devido ao maior acúmulo de matéria seca e macronutrientes por densidades crescentes de E. heterophylla. Conclui-se que a soja mantida em convivência com E. heterophylla teve o crescimento e o acúmulo de macronutrientes reduzidos em razão da interferência imposta pela planta daninha.The degree of weed interference depends on the density of the weeds infesting the soybean crop. The objective of this work was to evaluate the growth and mineral nutrition characteristics in soybean maintained in coexistence with increasing densities of Euphorbia heterophylla. The experiment was carried out in Jaboticabal, SP, Brazil, from October through December 2008, in pots maintained under open field conditions. The treatments consisted in submitting one soybean plant per pot to coexistence with 0, 1, 2, 4, 8 and 16 plants of E. heterophylla per pot, from sowing until the beginning of soybean flowering. At this period, only height and number of leaves were evaluated in soybean, while dry matter and macronutrient accumulation were evaluated in both species. Variation in plant height and reduction in the

  10. Períodos de interferência das plantas daninhas na cultura de cebola (Allium cepa transplantada Periods of weed interference with transplanted onion crop (Allium cepa

    Directory of Open Access Journals (Sweden)

    D.J. Soares

    2003-12-01

    Full Text Available O trabalho foi realizado com o objetivo de estudar os efeitos de períodos de convivência (0, 14, 28, 42, 56, 70, 84 e 98 dias após o transplantio de uma comunidade de plantas daninhas sobre a produtividade de quatro cultivares de cebola (Mercedes, Granex 33, Superex e Serrana, em sistema de transplantio de mudas. O experimento foi instalado em Jaboticabal-SP, de abril a outubro de 2000, utilizando delineamento experimental de blocos ao acaso, quatro repetições, em esquema fatorial 4 x 8. As principais populações de plantas daninhas no final dos períodos de convivência foram de Coronopus didymus, Amaranthus hybridus e Cyperus rotundus. Os cultivares Mercedes (2,90 kgm-2 e Granex 33 (2,64 kgm-2 foram os mais produtivos, independentemente da interferência das plantas daninhas. A convivência com as plantas daninhas durante os primeiros 98 dias reduziu a produtividade da cebola em 95% e o peso médio de bulbos em 91%. O período anterior à interferência (PAI foi de 42 dias, não havendo diferença entre os cultivares de cebola.This research was carried out to evaluate the effects of weed coexistence periods (0, 14, 28, 42, 56, 70, 84 and 98 days after transplanting on the productivity of four onion cultivars (Mercedez, Granex 33, Superex and Serrana. The experiment was installed in Jaboticabal - SP - Brazil, from April to October 2000, arranged in a randomized complete block design, with four replications, in a factorial design 4 x 8. The main weed populations at the end of the coexistence periods were Coronopus didymus, Amaranthus hybridus and Cyperus rotundus. The cultivars Mercedez (2.90 kg m-2 and Granex-33 (2.64 kg m-2 were the most productive, under the conditions of weed interference.Weed interference during the first 98 days reduced production weight around 95% and the average weight of bulbs was reduced by 91%. For all the cultivars, weed coexistence the during the first 42 days after transplanting did not reduce the total

  11. PACT- and RIG-I-Dependent Activation of Type I Interferon Production by a Defective Interfering RNA Derived from Measles Virus Vaccine

    Science.gov (United States)

    Ho, Ting-Hin; Kew, Chun; Lui, Pak-Yin; Chan, Chi-Ping; Satoh, Takashi; Akira, Shizuo

    2015-01-01

    ABSTRACT The live attenuated measles virus vaccine is highly immunostimulatory. Identification and characterization of its components that activate the innate immune response might provide new strategies and agents for the rational design and development of chemically defined adjuvants. In this study, we report on the activation of type I interferon (IFN) production by a defective interfering (DI) RNA isolated from the Hu-191 vaccine strain of measles virus. We found that the Hu-191 virus induced IFN-β much more potently than the Edmonston strain. In the search for IFN-inducing species in Hu-191, we identified a DI RNA specifically expressed by this strain. This DI RNA, which was of the copy-back type, was predicted to fold into a hairpin structure with a long double-stranded stem region of 206 bp, and it potently induced the expression of IFN-β. Its IFN-β-inducing activity was further enhanced when both cytoplasmic RNA sensor RIG-I and its partner, PACT, were overexpressed. On the contrary, this activity was abrogated in cells deficient in PACT or RIG-I. The DI RNA was found to be associated with PACT in infected cells. In addition, both the 5′-di/triphosphate end and the double-stranded stem region on the DI RNA were essential for its activation of PACT and RIG-I. Taken together, our findings support a model in which a viral DI RNA is sensed by PACT and RIG-I to initiate an innate antiviral response. Our work might also provide a foundation for identifying physiological PACT ligands and developing novel adjuvants or antivirals. IMPORTANCE The live attenuated measles virus vaccine is one of the most successful human vaccines and has largely contained the devastating impact of a highly contagious virus. Identifying the components in this vaccine that stimulate the host immune response and understanding their mechanism of action might help to design and develop better adjuvants, vaccines, antivirals, and immunotherapeutic agents. We identified and characterized

  12. Improved outcome with hematopoietic stem cell transplantation in a poor prognostic subgroup of infants with mixed-lineage-leukemia (MLL)-rearranged acute lymphoblastic leukemia: results from the Interfant-99 Study

    DEFF Research Database (Denmark)

    Mann, Georg; Attarbaschi, Andishe; Schrappe, Martin

    2010-01-01

    To define a role for hematopoietic stem cell transplantation (HSCT) in infants with acute lymphoblastic leukemia and rearrangements of the mixed-lineage-leukemia gene (MLL(+)), we compared the outcome of MLL(+) patients from trial Interfant-99 who either received chemotherapy only or HSCT. Of 376...

  13. Small RNA profiles from virus-infected fresh market vegetables.

    Science.gov (United States)

    Frizzi, Alessandra; Zhang, Yuanji; Kao, John; Hagen, Charles; Huang, Shihshieh

    2014-12-10

    Functional small RNAs, such as short interfering RNAs (siRNAs) and microRNAs (miRNAs), exist in freshly consumed fruits and vegetables. These siRNAs can be derived either from endogenous sequences or from viruses that infect them. Symptomatic tomatoes, watermelons, zucchini, and onions were purchased from grocery stores and investigated by small RNA sequencing. By aligning the obtained small RNA sequences to sequences of known viruses, four different viruses were identified as infecting these fruits and vegetables. Many of these virally derived small RNAs along with endogenous small RNAs were found to be highly complementary to human genes. However, the established history of safe consumption of these vegetables suggests that this sequence homology has little biological relevance. By extension, these results provide evidence for the safe use by humans and animals of genetically engineered crops using RNA-based suppression technologies, especially vegetable crops with virus resistance conferred by expression of siRNAs or miRNAs derived from viral sequences.

  14. Small RNA Detection by in Situ Hybridization Methods

    Directory of Open Access Journals (Sweden)

    Martyna O. Urbanek

    2015-06-01

    Full Text Available Small noncoding RNAs perform multiple regulatory functions in cells, and their exogenous mimics are widely used in research and experimental therapies to interfere with target gene expression. MicroRNAs (miRNAs are the most thoroughly investigated representatives of the small RNA family, which includes short interfering RNAs (siRNAs, PIWI-associated RNA (piRNAs, and others. Numerous methods have been adopted for the detection and characterization of small RNAs, which is challenging due to their short length and low level of expression. These include molecular biology methods such as real-time RT-PCR, northern blotting, hybridization to microarrays, cloning and sequencing, as well as single cell miRNA detection by microscopy with in situ hybridization (ISH. In this review, we focus on the ISH method, including its fluorescent version (FISH, and we present recent methodological advances that facilitated its successful adaptation for small RNA detection. We discuss relevant technical aspects as well as the advantages and limitations of ISH. We also refer to numerous applications of small RNA ISH in basic research and molecular diagnostics.

  15. As Interferências Externas e a Manutenção da Ordem Pública no Haiti * External Interferences and Maintenance of Public Order in Haiti

    Directory of Open Access Journals (Sweden)

    VANESSA BRAGA MATIJASCIC

    2012-05-01

    Full Text Available Este trabalho discutirá quais atores interferiram em assuntos internos do Estado haitiano ao longo da história, sobretudo, detendo-se a década de 1990. Analisaremos o perfil das forças militares e policiais que se constituíram no país, como elemento importante para compreender que, muitas vezes ao invés de proteger os cidadãos, as mesmas forças auxiliaram para que houvesse a opressão, instabilidade e insegurança para a maioria da população haitiana. Ao final, realizaremos o balanço das atividades internacionais promovidas pelas organizações internacionais na década de 1990. Palavras-chave: Intervenções militares – Haiti – Segurança interna.   Abstract: This paper will discuss which characters interfered in internal affairs in Haiti over the history, especially in the 1990's. We will analyze the profile of the military and police forces which established in the country, as an important element to understand that, many times, instead of protecting citizens, the same forces helped to have oppression, instability and insecurity for most of Haitian population. Finally, we will hold the balance of the activities promoted by international organizations in the 1990's. Keywords: Military interventions – Haiti – Internal security.

  16. An HIV p24 heptapeptide down-regulates antigen-specific responses in vitro interfering at the level of the T3-Ti complex.

    Science.gov (United States)

    Luzzati, A L; Giacomini, E; Giordani, L; Viora, M; Chersi, A; Camponeschi, B; Pugliese, O

    1994-07-01

    Ch7 (RGSDIAG), a synthetic heptapeptide derived from a conserved region of HIV p24 (aa 232-238), was previously shown to suppress antigen-induced responses in cultures of normal human peripheral blood lymphocytes (PBL). We show in this paper that Ch7 is the shortest peptide retaining full inhibitory capacity. Further, the peptide inhibited efficiently and in a dose-dependent manner the induction of a specific antibody response to the antigens SRC (sheep red cells) and Candida albicans but did not exert any effect on the induction of immunoglobulin-secreting cells in PWM-stimulated cultures. Finally, Ch7 inhibited anti-CD3-induced lymphoproliferation but did not affect anti-CD2 activation. These results suggest that a conserved epitope of HIV p24 may be able to prevent the induction of antigen-specific antibody responses by interfering with lymphocyte activation via the T3-Ti complex, resulting in the abrogation of immune functions that are defective in HIV-infected individuals.

  17. Interferência do ácido ascórbico na dosagem glicêmica - doi: 10.5102/ucs.v6i2.722

    Directory of Open Access Journals (Sweden)

    Aline Cardoso Barbosa

    2009-07-01

    Full Text Available Sabe-se que exames laboratoriais estão sujeitos a fatores interferentes. A literatura científica cita interferência do ácido ascórbico em dosagens que envolvam oxirredução, como a glicêmica. Devido a isto, buscou-se avaliar o efeito do ácido ascórbico sobre a dosagem glicêmica em dois tipos de soro controle submetidos a diferentes concentrações de ácido ascórbico, variando de 2,5 a 100 mg/dL. Utilizou-se um soro controle com valores normais de glicemia e outro com valores patológicos. Observou-se uma diminuição significativa (p<0,01 da glicemia em ambos, porém a amostra normal apresentou maior correlação negativa, chegando a 74% com a concentração de 100 mg/dL de ácido ascórbico, enquanto na amostra correspondente do soro patológico houve uma redução de 40% na dosagem glicêmica. O presente estudo demonstrou haver uma correlação negativa entre concentrações crescentes de ácido ascórbico e dosagem glicêmica.

  18. Interferência da disponibilidade de luz na resposta à adubação de plantios de enriquecimento com leguminosas arbóreas

    Directory of Open Access Journals (Sweden)

    Marco Aurélio de Carvalho Silva

    2013-03-01

    Full Text Available O objetivo deste trabalho foi avaliar a interferência da disponibilidade de luz na resposta à adubação de plantios de enriquecimento da capoeira com leguminosas arbóreas. As espécies Hymenaea courbaril, Stryphnodendron guianense, Parkia platycephala e Stryphnodendron microstachyum foram plantadas em capoeira, sob três tratamentos de fertilização: adubação orgânica, adubação orgânica acrescida de mineral e ausência de adubação. A disponibilidade de luz condicionou a resposta de P. platycephala e H. courbaril à fertilização. A aleatorização não foi suficiente para garantir condições semelhantes de luz nos plantios de enriquecimento. A variação na quantidade de luz incidente no sub‑bosque compromete a correta avaliação dos tratamentos de fertilização.

  19. Interfering signals and digital measurements

    International Nuclear Information System (INIS)

    Stulik, P.; Pilat, M.

    1976-01-01

    The possible occurrence was studied of unweighted voltage interference in measuring channels and the effect of the voltage on the measuring system where digital technology is used in the WWR-S reactor experimental loops. Various types of voltmeters were evaluated in the gas loop during measurements of the output signals of a Ni-NiCr jacket thermocouple, this both with an insulated and a noninsulated end. Also studied was digital measurement in measuring channels with vanadium SPN detectors. Two identical detectors were installed in the middle of the core and, assuming an identical neutron flux for both detectors, the effects were investigated of a different cable route design, of the combination of the connection of measuring central input circuits on the size of fluctuations of the measured output signal of both detectors, etc. The optimal value was also studied of the loading resistor incorporated in the measuring circuit. The relation was derived for digital measurement accuracy. It was confirmed experimentally and by calculation that unweighted voltage in series has the greatest effect on measurement accuracy. (Z.M.)

  20. Interfering with the neutron spin

    Indian Academy of Sciences (India)

    phases produced by flipper rotations and translations respectively. In the scheme of figure 1, a relative rotation δβ between the flippers F1 and F2 generates a pure geometric phase [3] equal to δβ. A relative translation δx on the other hand, produces a proportionate pure dynamical phase due to the guide field. B0. We have ...

  1. Transfection of small RNAs globally perturbs gene regulation by endogenous microRNAs

    DEFF Research Database (Denmark)

    Khan, Aly A; Betel, Doron; Miller, Martin L

    2009-01-01

    Transfection of small RNAs (such as small interfering RNAs (siRNAs) and microRNAs (miRNAs)) into cells typically lowers expression of many genes. Unexpectedly, increased expression of genes also occurs. We investigated whether this upregulation results from a saturation effect--that is, competition...... among the transfected small RNAs and the endogenous pool of miRNAs for the intracellular machinery that processes small RNAs. To test this hypothesis, we analyzed genome-wide transcript responses from 151 published transfection experiments in seven different human cell types. We show that targets...... of endogenous miRNAs are expressed at significantly higher levels after transfection, consistent with impaired effectiveness of endogenous miRNA repression. This effect exhibited concentration and temporal dependence. Notably, the profile of endogenous miRNAs can be largely inferred by correlating miRNA sites...

  2. A DNA vector-based RNAi technology to suppress gene expression in mammalian cells.

    Science.gov (United States)

    Sui, Guangchao; Soohoo, Christina; Affar, El Bachir; Gay, Frédérique; Shi, Yujiang; Forrester, William C; Shi, Yang

    2002-04-16

    Double-stranded RNA-mediated interference (RNAi) has recently emerged as a powerful reverse genetic tool to silence gene expression in multiple organisms including plants, Caenorhabditis elegans, and Drosophila. The discovery that synthetic double-stranded, 21-nt small interfering RNA triggers gene-specific silencing in mammalian cells has further expanded the utility of RNAi into mammalian systems. Here we report a technology that allows synthesis of small interfering RNAs from DNA templates in vivo to efficiently inhibit endogenous gene expression. Significantly, we were able to use this approach to demonstrate, in multiple cell lines, robust inhibition of several endogenous genes of diverse functions. These findings highlight the general utility of this DNA vector-based RNAi technology in suppressing gene expression in mammalian cells.

  3. The PSI/ETH small radiocarbon dating system

    International Nuclear Information System (INIS)

    Synal, H.-A.; Jacob, S.; Suter, M.

    2000-01-01

    A small and compact radiocarbon dating system has been built at PSI/ETH. The system is based on a National Electrostatics Corporation (NEC) pelletron accelerator with a maximum terminal voltage of 550 kV. It is the first accelerator mass spectrometry (AMS) system that uses 1 + ions at the high-energy end of the accelerator. Interfering isobaric molecules are destroyed by collisions in the gas stripper inside the accelerator. The system has been designed to fulfill two primary goals. First, it can be used as an experimental platform to study the relevant charge exchange and molecular break up processes at low energies. Second, it is able to perform high quality radiocarbon dating measurements. A detailed system description is given and results of performance tests are discussed

  4. The PSI/ETH small radiocarbon dating system

    Science.gov (United States)

    Synal, H.-A.; Jacob, S.; Suter, M.

    2000-10-01

    A small and compact radiocarbon dating system has been built at PSI/ETH. The system is based on a National Electrostatics Corporation (NEC) pelletron accelerator with a maximum terminal voltage of 550 kV. It is the first accelerator mass spectrometry (AMS) system that uses 1 + ions at the high-energy end of the accelerator. Interfering isobaric molecules are destroyed by collisions in the gas stripper inside the accelerator. The system has been designed to fulfill two primary goals. First, it can be used as an experimental platform to study the relevant charge exchange and molecular break up processes at low energies. Second, it is able to perform high quality radiocarbon dating measurements. A detailed system description is given and results of performance tests are discussed.

  5. Systematic characterization and fluorescence threshold strategies for the wideband integrated bioaerosol sensor (WIBS) using size-resolved biological and interfering particles

    Science.gov (United States)

    Savage, Nicole J.; Krentz, Christine E.; Könemann, Tobias; Han, Taewon T.; Mainelis, Gediminas; Pöhlker, Christopher; Huffman, J. Alex

    2017-11-01

    Atmospheric particles of biological origin, also referred to as bioaerosols or primary biological aerosol particles (PBAP), are important to various human health and environmental systems. There has been a recent steep increase in the frequency of published studies utilizing commercial instrumentation based on ultraviolet laser/light-induced fluorescence (UV-LIF), such as the WIBS (wideband integrated bioaerosol sensor) or UV-APS (ultraviolet aerodynamic particle sizer), for bioaerosol detection both outdoors and in the built environment. Significant work over several decades supported the development of the general technologies, but efforts to systematically characterize the operation of new commercial sensors have remained lacking. Specifically, there have been gaps in the understanding of how different classes of biological and non-biological particles can influence the detection ability of LIF instrumentation. Here we present a systematic characterization of the WIBS-4A instrument using 69 types of aerosol materials, including a representative list of pollen, fungal spores, and bacteria as well as the most important groups of non-biological materials reported to exhibit interfering fluorescent properties. Broad separation can be seen between the biological and non-biological particles directly using the five WIBS output parameters and by taking advantage of the particle classification analysis introduced by Perring et al. (2015). We highlight the importance that particle size plays on observed fluorescence properties and thus in the Perring-style particle classification. We also discuss several particle analysis strategies, including the commonly used fluorescence threshold defined as the mean instrument background (forced trigger; FT) plus 3 standard deviations (σ) of the measurement. Changing the particle fluorescence threshold was shown to have a significant impact on fluorescence fraction and particle type classification. We conclude that raising the

  6. Systematic characterization and fluorescence threshold strategies for the wideband integrated bioaerosol sensor (WIBS using size-resolved biological and interfering particles

    Directory of Open Access Journals (Sweden)

    N. J. Savage

    2017-11-01

    Full Text Available Atmospheric particles of biological origin, also referred to as bioaerosols or primary biological aerosol particles (PBAP, are important to various human health and environmental systems. There has been a recent steep increase in the frequency of published studies utilizing commercial instrumentation based on ultraviolet laser/light-induced fluorescence (UV-LIF, such as the WIBS (wideband integrated bioaerosol sensor or UV-APS (ultraviolet aerodynamic particle sizer, for bioaerosol detection both outdoors and in the built environment. Significant work over several decades supported the development of the general technologies, but efforts to systematically characterize the operation of new commercial sensors have remained lacking. Specifically, there have been gaps in the understanding of how different classes of biological and non-biological particles can influence the detection ability of LIF instrumentation. Here we present a systematic characterization of the WIBS-4A instrument using 69 types of aerosol materials, including a representative list of pollen, fungal spores, and bacteria as well as the most important groups of non-biological materials reported to exhibit interfering fluorescent properties. Broad separation can be seen between the biological and non-biological particles directly using the five WIBS output parameters and by taking advantage of the particle classification analysis introduced by Perring et al. (2015. We highlight the importance that particle size plays on observed fluorescence properties and thus in the Perring-style particle classification. We also discuss several particle analysis strategies, including the commonly used fluorescence threshold defined as the mean instrument background (forced trigger; FT plus 3 standard deviations (σ of the measurement. Changing the particle fluorescence threshold was shown to have a significant impact on fluorescence fraction and particle type classification. We conclude that

  7. STOOKE SMALL BODIES MAPS

    Data.gov (United States)

    National Aeronautics and Space Administration — The Stooke Small Bodies Map collection contains maps of small solar system bodies in various projections, with and without latitude/longiude grids. The maps are...

  8. Targeted interfering DEP domain containing 1 protein induces apoptosis in A549 lung adenocarcinoma cells through the NF-κB signaling pathway.

    Science.gov (United States)

    Wang, Qingqing; Li, Aili; Jin, Junfei; Huang, Guojin

    2017-01-01

    Ectopic expression of DEP domain containing 1 (DEPDC1) in lung adenocarcinomas is associated with poor prognosis, but its role and the underlying mechanism remain unknown. In this study, DEPDC1 expression in lung cancer cell lines was examined with Western blot assay, and DEPDC1-positive cell A549 was selected for further experiments. DEPDC1 inhibitor miR-130a was overexpressed in A549 cells, and the proliferation and apoptosis of these cells were analyzed with cell counting and flow cytometry assay. Interfering peptide 11R-DEP:611-628 and JNK inhibitor SP600125 were used alone or in combination to treat A549 cells, and the cell proliferation and apoptosis were assessed by flow cytometry assay; caspase 3 and cleaved caspase 3, phosphor-JNK, and total JNK were detected by Western blotting; and nuclear factor kappa B (NF-κB) localization was determined by immunofluorescence staining. We found that miR-130a and 11R-DEP:611-628 peptides (5 μM) both inhibited A549 proliferation and induced apoptosis. We observed that 11R-DEP:611-628 peptide treatment resulted in elevated A20 expression, dramatically reduced nuclear NF-κB, and increased phosphor-JNK. These findings indicate that DEPDC1 inhibits apoptosis of A549 cell by suppressing A20 expression to regulate NF-κB activity, and that JNK plays a protective role upon 11R-DEP:611-628 peptide treatment. In conclusion, DEPDC1 might be a novel therapeutic target for lung cancer, and the 11R-DEP:611-628 peptide is a potent apoptosis inducer in A549 cells.

  9. Interferência interespecífica entre Amaranthus hybridus L. e Amaranthus viridis L. Interspecific interference between Amaranthus hybridus L. and Amaranthus viridis L.

    Directory of Open Access Journals (Sweden)

    Angela Maria Maluf

    1999-05-01

    Full Text Available O objetivo deste trabalho foi estudar a interferência interespecífica entre duas espécies de Amaranthus -- A. viridis e A. hybridus ¾, esta última com dois biótipos distintos (verde e roxo; ambas ocorriam associadas em dois locais. Nas populações de cada local foram feitos ensaios de substituição independentes, em vasos, nos quais observou-se que as populações que germinam mais prontamente são as que vencem em competição, ou seja, se estabelecem e produzem maior número de sementes. Houve tendência de A. hybridus (tipo verde dominar tanto A. hybridus (tipo roxo como A. viridis, e de A. hybridus (tipo roxo dominar A. viridis. Em cultivo misto, houve casos em que as espécies estavam competindo pelos mesmos recursos, ou explorando recursos diferentes do ambiente, ou mesmo com antagonismo mútuo.The objective of this paper was to study the interspecific interference between two Amaranthus species -- A. viridis and A. hybridus --, the latter with two distinct biotypes (green and purple; both species ocurred in two localities. In the populations of each of the locations, some independent substitution trials were made in pots, and it could be concluded that the populations that germinate more readily are those which are superior in competition i.e., those that establish themselves and produce the largest number of seeds. There was a tendency for A. hybridus (green biotype to dominate both A. hybridus (purple biotype and A. viridis, and for A. hybridus (purple biotype to dominate A. viridis. In mixed stands, there were cases where the species were competing for the same resources, cases where they were exploiting different environmental resources, and even cases of mutual antagonism.

  10. Use of short interfering RNA delivered by cationic liposomes to enable efficient down-regulation of PTPN22 gene in human T lymphocytes.

    Directory of Open Access Journals (Sweden)

    Valentina Perri

    Full Text Available Type 1 diabetes and thyroid disease are T cell-dependent autoimmune endocrinopathies. The standard substitutive administration of the deficient hormones does not halt the autoimmune process; therefore, development of immunotherapies aiming to preserve the residual hormonal cells, is of crucial importance. PTPN22 C1858T mutation encoding for the R620W lymphoid tyrosine phosphatase variant, plays a potential pathophysiological role in autoimmunity. The PTPN22 encoded protein Lyp is a negative regulator of T cell antigen receptor signaling; R620W variant, leading to a gain of function with paradoxical reduced T cell activation, may represent a valid therapeutic target. We aimed to develop novel wild type PTPN22 short interfering RNA duplexes (siRNA and optimize their delivery into Jurkat T cells and PBMC by using liposomal carriers. Conformational stability, size and polydispersion of siRNA in lipoplexes was measured by CD spectroscopy and DLS. Lipoplexes internalization and toxicity evaluation was assessed by confocal microscopy and flow cytometry analysis. Their effect on Lyp expression was evaluated by means of Western Blot and confocal microscopy. Functional assays through engagement of TCR signaling were established to evaluate biological consequences of down-modulation. Both Jurkat T cells and PBMC were efficiently transfected by stable custom lipoplexes. Jurkat T cell morphology and proliferation was not affected. Lipoplexes incorporation was visualized in CD3+ but also in CD3- peripheral blood immunotypes without signs of toxicity, damage or apoptosis. Efficacy in affecting Lyp protein expression was demonstrated in both transfected Jurkat T cells and PBMC. Moreover, impairment of Lyp inhibitory activity was revealed by increase of IL-2 secretion in culture supernatants of PBMC following anti-CD3/CD28 T cell receptor-driven stimulation. The results of our study open the pathway to future trials for the treatment of autoimmune diseases based

  11. Effectiveness of Cyantraniliprole for Managing Bemisia tabaci (Hemiptera: Aleyrodidae) and Interfering with Transmission of Tomato Yellow Leaf Curl Virus on Tomato.

    Science.gov (United States)

    Caballero, Rafael; Schuster, David J; Peres, Natalia A; Mangandi, Jozer; Hasing, Tomas; Trexler, Fred; Kalb, Steve; Portillo, Héctor E; Marçon, Paula C; Annan, I B

    2015-06-01

    Cyantraniliprole is the second xylem-systemic active ingredient in the new anthranilic diamide class. Greenhouse (2006), growth chamber (2007), and field studies (2009-2010) were conducted to determine the efficacy of cyantraniliprole for managing Bemisia tabaci (Gennadius) biotype B and in interfering with transmission of tomato yellow leaf curl virus (TYLCV) by this whitefly. Cyantraniliprole applied as soil treatments (200 SC) or foliar sprays (100 OD) provided excellent adult whitefly control, TYLCV suppression, and reduced oviposition and nymph survival, comparable to current standards. The positive results observed in these greenhouse experiments with a high level of insect pressure (10× the field threshold of one adult per plant) and disease pressure (five adults per plant, with a high level of confidence that TYLCV virulent adults were used), indicate a great potential for cyantraniliprole to be used in a whitefly management program. Field evaluations of soil drench treatments confirmed the suppression of TYLCV transmission demonstrated in the greenhouse studies. Field studies in 2009 and 2010 showed that cyantraniliprole (200 SC) provided TYLCV suppression for 2 wk after a drench application, when using a susceptible (2009) or imidacloprid-tolerant (2010) whitefly population. Cyantraniliprole was demonstrated to be a promising tool for management of TYLCV in tomato production, which is very difficult and expensive, and which has limited options. The integration of cyantraniliprole into a resistance management program will help to ensure the continued sustainability of this and current insecticides used for the management of insect vectors, including whiteflies and the TYLCV they spreads. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  12. Projeto BIOS: a fotografia como elemento de percepção, visão e interferência nas questões ambientais

    Directory of Open Access Journals (Sweden)

    Mário Bittencourt Monteiro

    2004-12-01

    Full Text Available Objetiva-se com este artigo, apresentar o Projeto BIOS, que vem sendo desenvolvido há mais de seis anos pelo Núcleo de Fotografia da Faculdade de Biblioteconomia e Comunicação da Universidade Federal do Rio Grande do Sul (FABICO/UFRGS, como uma atividade de pesquisa e extensão, junto à Fundação Zoobotânica do Rio Grande do Sul, e mais recentemente junto às escolas municipais de 1º. e 2º. Graus de São José dos Ausentes, RS . Apresenta as suas linhas de ação, que priorizam a colocação da Fotografia como vetor principal de apoio à Educação Ambiental junto a diversos públicos. Também discorre sob que forma a Fotografia está sendo aplicada, abrangendo suas questões teórico-filosóficas, suas interferências no desenvolvimento de maiores estágios das percepções, leitura e críticas às questões ambientais alcançadas pelos públicos envolvidos. Concomitante a isso, versa sobre as maneiras como vem sendo desenvolvida e aplicada a Teoria dos Universos Circundantes (MONTEIRO, 2000, enquanto método de percepção ambiental e obtenção fotográfica, nos trabalhos de fotografia ambiental e fotografia biológica.

  13. Validating the use of short interfering RNA as a novel technique for cell-specific target gene knockdown in lung ischemia-reperfusion injury.

    Science.gov (United States)

    Merry, Heather E; Phelan, Patrick; Hwang, Billanna; Mulligan, Michael S

    2016-02-01

    Short interfering RNA is an effective method for target gene knockdown. However, concerns surround the design, administration, efficacy, specificity, and immunostimulatory potential. Although uptake by alveolar macrophages has been demonstrated, studies have not examined its use in lung ischemia-reperfusion injury. We describe the validation of short interference RNA as a novel technique for cell-specific target gene knockdown in our model of lung ischemia-reperfusion injury. Dose-response experiments were performed, and 3 distinct sequences of toll-like receptor-4, toll-like receptor-2, and myeloid differentiation factor-88 short interference RNA were tested for efficacy of knockdown. Saline, lipid vector, and noncoding short interference RNA controls were used. Similar experiments were performed in primary cultures of resident pulmonary cells. Target protein knockdown was assessed by Western blot. Rat serum and cell culture media were assessed for interferon and cytokine production. Biotin labeling was used to assess short interference RNA uptake. Target protein expression was significantly reduced using short interference RNA. However, toll-like receptor-4 knockdown was isolated to alveolar macrophages, and biotin labeling confirmed toll-like receptor-4 short interference RNA localization to alveolar macrophages. There was significant knockdown of toll-like receptor-4 expression in cultured cells treated with toll-like receptor-4 short interference RNA. There was no significant change in interferon production after short interference RNA treatment. There was effective target protein knockdown with each sequence used. Short interference RNA is a valid method for achieving target protein knockdown in alveolar macrophages and is an important tool in the evaluation of its role in the development of lung ischemia-reperfusion injury. Copyright © 2016 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.

  14. The 3'-terminal 55 nucleotides of bovine coronavirus defective interfering RNA harbor cis-acting elements required for both negative- and positive-strand RNA synthesis.

    Directory of Open Access Journals (Sweden)

    Wei-Yu Liao

    Full Text Available The synthesis of the negative-strand [(--strand] complement of the ∼30 kilobase, positive-strand [(+-strand] coronaviral genome is a necessary early step for genome replication. The identification of cis-acting elements required for (--strand RNA synthesis in coronaviruses, however, has been hampered due to insufficiencies in the techniques used to detect the (--strand RNA species. Here, we employed a method of head-to-tail ligation and real-time quantitative reverse transcription polymerase chain reaction (qRT-PCR to detect and quantitate the synthesis of bovine coronavirus (BCoV defective interfering (DI RNA (- strands. Furthermore, using the aforementioned techniques along with Northern blot assay, we specifically defined the cis-acting RNA elements within the 3'-terminal 55 nucleotides (nts which function in the synthesis of (-- or (+-strand BCoV DI RNA. The major findings are as follows: (i nts from -5 to -39 within the 3'-terminal 55 nts are the cis-acting elements responsible for (--strand BCoV DI RNA synthesis, (ii nts from -3 to -34 within the 3'-terminal 55 nts are cis-acting elements required for (+-strand BCoV DI RNA synthesis, and (iii the nucleotide species at the 3'-most position (-1 is important, but not critical, for both (-- and (+-strand BCoV DI RNA synthesis. These results demonstrate that the 3'-terminal 55 nts in BCoV DI RNA harbor cis-acting RNA elements required for both (-- and (+-strand DI RNA synthesis and extend our knowledge on the mechanisms of coronavirus replication. The method of head-to-tail ligation and qRT-PCR employed in the study may also be applied to identify other cis-acting elements required for (--strand RNA synthesis in coronaviruses.

  15. Gender Segregation Small Firms

    OpenAIRE

    Kenneth R Troske; William J Carrington

    1992-01-01

    This paper studies interfirm gender segregation in a unique sample of small employers. We focus on small firms because previous research on interfirm segregation has studied only large firms and because it is easier to link the demographic characteristics of employers and employees in small firms. This latter feature permits an assessment of the role of employer discrimination in creating gender segregation. Our first finding is that interfirm segregation is prevalent among small employers. I...

  16. Períodos de interferência de maria-pretinha sobre tomateiro industrial Periods of nightshade interference in processing tomato

    Directory of Open Access Journals (Sweden)

    Daniel D Hernandez

    2007-06-01

    Full Text Available Determinou-se os efeitos da convivência com plantas de maria-pretinha sobre a produtividade do tomateiro industrial, híbrido Heinz 9992, em um experimento com dois grupos de tratamentos: no primeiro, o tomate permaneceu livre da competição (60 mil plantas ha-1 de maria-pretinha do transplantio até 15; 30; 45; 60; 75; 90; 105 e 120 dias (colheita; no segundo, a cultura permaneceu em competição com a maria-pretinha do transplantio até os mesmos períodos citados. Utilizaram-se blocos casualizados, três repetições e parcelas de quatro linhas. Altura, área foliar e massa seca da parte aérea da maria-pretinha foram obtidas a partir de amostras de dez plantas. A área foliar das plantas de maria-pretinha cresceu até 75 dias de convivência com as plantas de tomate (1.588 dm² planta-1, a altura até 60 dias de convivência (85 cm e a massa seca da parte aérea até 120 dias de convivência (31,7 g planta-1. As produtividades mais alta (108,6 t ha-1 ou 87,6% da produção total de frutos e mais baixa (14,2 t ha-1; 59,0% de frutos maduros de tomate foram observadas quando a convivência entre tomate e maria-pretinha ocorreu respectivamente apenas nos 15 primeiros dias e ao longo de todo o ciclo do tomate. Nestes tratamentos, o peso médio de frutos maduros foi de respectivamente 58,7 e 38,0 g. Verificou-se que cada cm² de acréscimo em área foliar das plantas de maria-pretinha causou uma redução de 0,04 t ha-1 na produção de frutos maduros (PFM (R² = 0,90, cada centímetro em altura da planta daninha reduziu 0,82 t ha-1 na PFM (R² = 0,78 e cada grama de acréscimo em massa seca de caules e folhas da planta daninha causou uma redução de 2,84 t ha-1 PFM (R² = 0,97. O período anterior à interferência, considerando-se a redução na produtividade do tomate em 5%, foi de 27 dias após o transplantio (DAT da cultura; o período total de prevenção à interferência foi de 46 DAT e, o período crítico de prevenção à interfer

  17. Identification and functional characterization of small non-coding RNAs in Xanthomonas oryzae pathovar oryzae

    Directory of Open Access Journals (Sweden)

    Zhang Jie-Qiong

    2011-01-01

    Full Text Available Abstract Background Small non-coding RNAs (sRNAs are regarded as important regulators in prokaryotes and play essential roles in diverse cellular processes. Xanthomonas oryzae pathovar oryzae (Xoo is an important plant pathogenic bacterium which causes serious bacterial blight of rice. However, little is known about the number, genomic distribution and biological functions of sRNAs in Xoo. Results Here, we performed a systematic screen to identify sRNAs in the Xoo strain PXO99. A total of 850 putative non-coding RNA sequences originated from intergenic and gene antisense regions were identified by cloning, of which 63 were also identified as sRNA candidates by computational prediction, thus were considered as Xoo sRNA candidates. Northern blot hybridization confirmed the size and expression of 6 sRNA candidates and other 2 cloned small RNA sequences, which were then added to the sRNA candidate list. We further examined the expression profiles of the eight sRNAs in an hfq deletion mutant and found that two of them showed drastically decreased expression levels, and another exhibited an Hfq-dependent transcript processing pattern. Deletion mutants were obtained for seven of the Northern confirmed sRNAs, but none of them exhibited obvious phenotypes. Comparison of the proteomic differences between three of the ΔsRNA mutants and the wild-type strain by two-dimensional gel electrophoresis (2-DE analysis showed that these sRNAs are involved in multiple physiological and biochemical processes. Conclusions We experimentally verified eight sRNAs in a genome-wide screen and uncovered three Hfq-dependent sRNAs in Xoo. Proteomics analysis revealed Xoo sRNAs may take part in various metabolic processes. Taken together, this work represents the first comprehensive screen and functional analysis of sRNAs in rice pathogenic bacteria and facilitates future studies on sRNA-mediated regulatory networks in this important phytopathogen.

  18. Regulation of Small RNAs and Corresponding Targets in Nod Factor-Induced Phaseolus vulgaris Root Hair Cells.

    Science.gov (United States)

    Formey, Damien; Martín-Rodríguez, José Ángel; Leija, Alfonso; Santana, Olivia; Quinto, Carmen; Cárdenas, Luis; Hernández, Georgina

    2016-06-04

    A genome-wide analysis identified the set of small RNAs (sRNAs) from the agronomical important legume Phaseolus vulgaris (common bean), including novel P. vulgaris-specific microRNAs (miRNAs) potentially important for the regulation of the rhizobia-symbiotic process. Generally, novel miRNAs are difficult to identify and study because they are very lowly expressed in a tissue- or cell-specific manner. In this work, we aimed to analyze sRNAs from common bean root hairs (RH), a single-cell model, induced with pure Rhizobium etli nodulation factors (NF), a unique type of signal molecule. The sequence analysis of samples from NF-induced and control libraries led to the identity of 132 mature miRNAs, including 63 novel miRNAs and 1984 phasiRNAs. From these, six miRNAs were significantly differentially expressed during NF induction, including one novel miRNA: miR-RH82. A parallel degradome analysis of the same samples revealed 29 targets potentially cleaved by novel miRNAs specifically in NF-induced RH samples; however, these novel miRNAs were not differentially accumulated in this tissue. This study reveals Phaseolus vulgaris-specific novel miRNA candidates and their corresponding targets that meet all criteria to be involved in the regulation of the early nodulation events, thus setting the basis for exploring miRNA-mediated improvement of the common bean-rhizobia symbiosis.

  19. Engineering of small interfering RNA-loaded lipidoid-poly(DL-lactic-co-glycolic acid) hybrid nanoparticles for highly efficient and safe gene silencing: A quality by design-based approach

    DEFF Research Database (Denmark)

    Thanki, Kaushik; Zeng, Xianghui; Justesen, Sarah

    2017-01-01

    used and poorly tolerated cationic lipids might be replaced with more efficacious and safe lipidoids as the lipid component of siRNA-loaded lipid-polymer hybrid nanoparticles (LPNs) for achieving more efficient gene silencing at lower and safer doses. However, formulation design of such a complex......), eventually resulting in the identification of a robust, highly efficacious and safe formulation. A 17-run design of experiment with an I-optimal approach was performed to systematically assess the effect of selected variables on critical quality attributes (CQAs), i.e. physicochemical properties...... in siRNA loading as compared to reference LPNs modified with the commonly used cationic lipid dioleyltrimethylammonium propane (DOTAP). Thus, lipidoid-modified LPNs show highly promising prospects for efficient and safe intracellular delivery of siRNA....

  20. SearchSmallRNA: a graphical interface tool for the assemblage of viral genomes using small RNA libraries data.

    Science.gov (United States)

    de Andrade, Roberto R S; Vaslin, Maite F S

    2014-03-07

    Next-generation parallel sequencing (NGS) allows the identification of viral pathogens by sequencing the small RNAs of infected hosts. Thus, viral genomes may be assembled from host immune response products without prior virus enrichment, amplification or purification. However, mapping of the vast information obtained presents a bioinformatics challenge. In order to by pass the need of line command and basic bioinformatics knowledge, we develop a mapping software with a graphical interface to the assemblage of viral genomes from small RNA dataset obtained by NGS. SearchSmallRNA was developed in JAVA language version 7 using NetBeans IDE 7.1 software. The program also allows the analysis of the viral small interfering RNAs (vsRNAs) profile; providing an overview of the size distribution and other features of the vsRNAs produced in infected cells. The program performs comparisons between each read sequenced present in a library and a chosen reference genome. Reads showing Hamming distances smaller or equal to an allowed mismatched will be selected as positives and used to the assemblage of a long nucleotide genome sequence. In order to validate the software, distinct analysis using NGS dataset obtained from HIV and two plant viruses were used to reconstruct viral whole genomes. SearchSmallRNA program was able to reconstructed viral genomes using NGS of small RNA dataset with high degree of reliability so it will be a valuable tool for viruses sequencing and discovery. It is accessible and free to all research communities and has the advantage to have an easy-to-use graphical interface. SearchSmallRNA was written in Java and is freely available at http://www.microbiologia.ufrj.br/ssrna/.

  1. Dispositivos Eletrônicos Portáteis: Interferências nos instrumentos de comunicação e navegação das aeronaves / Portable Electronic Devices: Interference in navigation and communication systems of aircrafts

    Directory of Open Access Journals (Sweden)

    João Pedro de França Santos

    2017-04-01

    Full Text Available Resumo Propósito – Analisar as interferências nos instrumentos de comunicação e navegação das aeronaves causadas por dispositivos eletrônicos portáteis. Metodologia – Este artigo apresenta uma abordagem sobre o método de funcionamento dos dispositivos eletrônicos portáteis, uma pesquisa exploratória das regulamentações brasileiras e internacionais, bem como uma análise de quais são os instrumentos passíveis de interferência e quais os efeitos dessas interferências. Resultados – As interferências existem e podem ser evitadas. Cada país possui as suas regras de utilização e também os responsáveis por permitir e fiscalizar o uso destes dispositivos abordo de aeronaves. Implicações práticas – Os resultados nos mostram as diferentes formas de regulamentação no mundo apesar dos dispositivos serem iguais no mundo todo. Abstract Purpose – To analyze interferences on navigation and communication systems caused by portable electronic devices. Methodology – This article tackles the operation method of the portable electronic device, exploratory research of Brazil’s regulation and other countries, as well as lists instruments that can be under the effect of those interferences. Findings – Interferences exist and they can be avoided. Each country has its usage rules and those responsible for allowing and supervise the use of these devices onboard aircraft. Practical implications – The findings show us the different ways of regulating worldwide the same portable electronic devices.

  2. Small cell glioblastoma or small cell carcinoma

    DEFF Research Database (Denmark)

    Hilbrandt, Christine; Sathyadas, Sathya; Dahlrot, Rikke H

    2013-01-01

    was admitted to the hospital with left-sided loss of motor function. A MRI revealed a 6 cm tumor in the right temporoparietal area. The histology was consistent with both glioblastoma multiforme (GBM) and small cell lung carcinoma (SCLC) but IHC was suggestive of a SCLC metastasis. PET-CT revealed...

  3. Small Quantum Structures with Small State Spaces

    Science.gov (United States)

    Navara, Mirko

    2008-01-01

    We summarize and extend results about “small” quantum structures with small dimensions of state spaces. These constructions have contributed to the theory of orthomodular lattices. More general quantum structures (orthomodular posets, orthoalgebras, and effect algebras) admit sometimes simplifications, but there are problems where no progress has been achieved.

  4. The cytoskeletal inhibitors latrunculin A and blebbistatin exert antitumorigenic properties in human hepatocellular carcinoma cells by interfering with intracellular HuR trafficking

    International Nuclear Information System (INIS)

    Doller, Anke; Badawi, Amel; Schmid, Tobias; Brauß, Thilo; Pleli, Thomas; Meyer zu Heringdorf, Dagmar; Piiper, Albrecht; Pfeilschifter, Josef; Eberhardt, Wolfgang

    2015-01-01

    The impact of the RNA-binding protein HuR for the post-transcriptional deregulation of tumor-relevant genes is well established. Despite of elevations in HuR expression levels, an increase in cytoplasmic HuR abundance in many cases correlates with a high grade of malignancy. Here, we demonstrated that administration of the actin-depolymerizing macrolide latrunculin A, or blebbistatin, an inhibitor of myosin II ATPase activity, caused a dose- and time-dependent reduction in the high cytoplasmic HuR content of HepG2 and Huh7 hepatocellular carcinoma (HCC) cells. Subcellular fractionation revealed that in addition, both inhibitors strongly attenuated cytoskeletal and membrane-bound HuR abundance and conversely increased the HuR amount in nuclear cell fractions. Concomitant with changes in intracellular HuR localization, both cytoskeletal inhibitors markedly decreased the half-lives of cyclooxygenase-2 (COX-2), cyclin A and cyclin D 1 encoding mRNAs resulting in a significant reduction in their expression levels in HepG2 cells. Importantly, a similar reduction in the expression of these HuR targets was achieved by a RNA interference (RNAi)-mediated knockdown of either HuR or nonmuscle myoin IIA. Using polysomal fractionation, we further demonstrate that the decrease in cytoplasmic HuR by latrunculin A or blebbistatin is accompanied by a marked change in the allocation of HuR and its mRNA cargo from polysomes to ribonucleoprotein (RNP) particles. Functionally, the basal migration and prostaglandin E 2 synthesis are similarly impaired in inhibitor-treated and stable HuR-knockdown HepG2 cells. Our data demonstrate that interfering with the actomyosin-dependent HuR trafficking may comprise a valid therapeutic option for antagonizing pathologic posttranscriptional gene expression by HuR and furthermore emphasize the potential benefit of HuR inhibitory strategies for treatment of HCC. - Highlights: • We tested the effects of latrunculin A and blebbistatin on different Hu

  5. The cytoskeletal inhibitors latrunculin A and blebbistatin exert antitumorigenic properties in human hepatocellular carcinoma cells by interfering with intracellular HuR trafficking

    Energy Technology Data Exchange (ETDEWEB)

    Doller, Anke; Badawi, Amel [Pharmazentrum Frankfurt/ZAFES, Klinikum der Goethe-Universität Frankfurt, Frankfurt/Main (Germany); Schmid, Tobias; Brauß, Thilo [Institut für Biochemie I (Pathobiochemie), Klinikum der Goethe-Universität Frankfurt, Frankfurt/Main (Germany); Pleli, Thomas [Medizinische Klinik 1, Schwerpunkt Gastroenterologie und Hepatologie, Klinikum der Goethe-Universität Frankfurt, Frankfurt/Main (Germany); Meyer zu Heringdorf, Dagmar [Pharmazentrum Frankfurt/ZAFES, Klinikum der Goethe-Universität Frankfurt, Frankfurt/Main (Germany); Piiper, Albrecht [Medizinische Klinik 1, Schwerpunkt Gastroenterologie und Hepatologie, Klinikum der Goethe-Universität Frankfurt, Frankfurt/Main (Germany); Pfeilschifter, Josef [Pharmazentrum Frankfurt/ZAFES, Klinikum der Goethe-Universität Frankfurt, Frankfurt/Main (Germany); Eberhardt, Wolfgang, E-mail: w.eberhardt@em.uni-frankfurt.de [Pharmazentrum Frankfurt/ZAFES, Klinikum der Goethe-Universität Frankfurt, Frankfurt/Main (Germany)

    2015-01-01

    The impact of the RNA-binding protein HuR for the post-transcriptional deregulation of tumor-relevant genes is well established. Despite of elevations in HuR expression levels, an increase in cytoplasmic HuR abundance in many cases correlates with a high grade of malignancy. Here, we demonstrated that administration of the actin-depolymerizing macrolide latrunculin A, or blebbistatin, an inhibitor of myosin II ATPase activity, caused a dose- and time-dependent reduction in the high cytoplasmic HuR content of HepG2 and Huh7 hepatocellular carcinoma (HCC) cells. Subcellular fractionation revealed that in addition, both inhibitors strongly attenuated cytoskeletal and membrane-bound HuR abundance and conversely increased the HuR amount in nuclear cell fractions. Concomitant with changes in intracellular HuR localization, both cytoskeletal inhibitors markedly decreased the half-lives of cyclooxygenase-2 (COX-2), cyclin A and cyclin D{sub 1} encoding mRNAs resulting in a significant reduction in their expression levels in HepG2 cells. Importantly, a similar reduction in the expression of these HuR targets was achieved by a RNA interference (RNAi)-mediated knockdown of either HuR or nonmuscle myoin IIA. Using polysomal fractionation, we further demonstrate that the decrease in cytoplasmic HuR by latrunculin A or blebbistatin is accompanied by a marked change in the allocation of HuR and its mRNA cargo from polysomes to ribonucleoprotein (RNP) particles. Functionally, the basal migration and prostaglandin E{sub 2} synthesis are similarly impaired in inhibitor-treated and stable HuR-knockdown HepG2 cells. Our data demonstrate that interfering with the actomyosin-dependent HuR trafficking may comprise a valid therapeutic option for antagonizing pathologic posttranscriptional gene expression by HuR and furthermore emphasize the potential benefit of HuR inhibitory strategies for treatment of HCC. - Highlights: • We tested the effects of latrunculin A and blebbistatin on

  6. Interferência da microbiota autóctone do queijo coalho sobre Staphylococcus coagulase positiva Interference of autochthonous microbiota of curd cheese on Staphylococcus coagulase positive

    Directory of Open Access Journals (Sweden)

    Terezinha Feitosa Machado

    2011-06-01

    Full Text Available Níveis elevados de contaminantes microbiológicos, comumente encontrados em alimentos de origem animal e ambientes de processamento de alimentos, são aptos de impedir o crescimento de patógenos nestes produtos. Em alguns contextos onde bactérias ácido láticas (BAL constituem a microbiota dominante, como nos produtos lácteos, Staphylococcus coagulase positiva (SCP colonizam, persistem e produzem intoxicação alimentar. Com o objetivo de verificar a possível interferência da microbiota encontrada no queijo Coalho sobre a presença de SCP, 64 amostras provenientes de 16 laticínios foram submetidas a análises microbiológicas para determinar os níveis de microrganismos aeróbios mesófilos (MAM, BAL e SCP. Os resultados obtidos mostraram que a microbiota autóctone das amostras analisadas não gerou condições inadequadas ao crescimento, desenvolvimento e isolamento de SCP, uma vez que este patógeno foi detectado mesmo nas amostras que apresentaram altos níveis de contagens de MAM e BAL.High levels of microbial contamination, commonly found in animal origin foods and food processing environments, are able to hinder the growth in these products. In some contexts where lactic acid bacteria (LAB are the normal dominant microbiota, such as in fermented food, Staphylococcus coagulase positive (SCP colonises, persists and produces food poisoning. With the aim of verifying the interference of autochthonous microbiota encountered in Curd cheese over the presence of Staphylococcus aureus, 64 samples from 16 dairy were submitted to microbiological analysis to determine the levels of Microorganisms aerobes mesophilics (MAM, LAB and SCP. The results showed that the indigenous microbiota of the samples did not lead to inadequate growth, development and isolation of SCP, since this pathogen was detected even in samples with high levels of counts of AM and BAL.

  7. Sulforaphane reduces vascular inflammation in mice and prevents TNF-α-induced monocyte adhesion to primary endothelial cells through interfering with the NF-κB pathway.

    Science.gov (United States)

    Nallasamy, Palanisamy; Si, Hongwei; Babu, Pon Velayutham Anandh; Pan, Dengke; Fu, Yu; Brooke, Elizabeth A S; Shah, Halley; Zhen, Wei; Zhu, Hong; Liu, Dongmin; Li, Yunbo; Jia, Zhenquan

    2014-08-01

    -inflammatory effect of sulforaphane may be, at least in part, associated with interfering with the NF-κB pathway. Copyright © 2014 Elsevier Inc. All rights reserved.

  8. Interferência da coloração de esmaltes de unha e do tempo na oximetria de pulso em voluntários sadios

    Directory of Open Access Journals (Sweden)

    Miyake Mara Harumi

    2003-01-01

    Full Text Available INTRODUÇÃO: A oximetria de pulso é um método não invasivo de mensuração da saturação periférica da oxiemoglobina (SpO2. É freqüentemente utilizado em unidades de emergência, de terapia intensiva e em centro cirúrgico. A leitura da oximetria de pulso tem acurácia limitada na presença de metaemoglobina, carboxiemoglobina, anemia, vasoconstrição periférica, esmalte de unha, luz fluorescente e movimentação. OBJETIVO: Avaliar a interferência da coloração de esmalte de unha e do tempo sobre a SpO2 em indivíduos sadios. MÉTODO: Participaram do estudo 61 voluntárias sadias, com idades entre 18 e 32 anos. Foi avaliada SpO2 nas seguintes colorações de esmaltes: base (dedo mínimo, rosa claro (dedo anular, rosa claro com cintilante (dedo médio e vermelha (polegar. O indicador não recebeu esmalte. Foi analisado o tempo para cada coloração de esmalte, a cada minuto até completar cinco minutos. RESULTADOS: Quando comparadas as medidas da SpO2 com o controle, as colorações base (p = 0,56, rosa claro (p = 0,56 e rosa claro com cintilante (p = 0,37 não apresentaram diferença estatisticamente significante. A SpO2 apresentou variação significante na cor vermelha (p < 0,001, porém manteve-se dentro dos parâmetros de normalidade. Não houve variação significativa da SpO2 ao longo do tempo. CONCLUSÃO: Apesar da diferença encontrada com o uso de esmalte vermelho, todas as medidas da SpO2 obtidas encontraram-se dentro do intervalo de normalidade, para indivíduos normais. A análise de cada cor de esmalte de unha em relação ao tempo mostrou que não houve variação na leitura da SpO2 .

  9. Interferência de Raphanus sativus sobre cultivares de soja durante a fase vegetativa de desenvolvimento da cultura Raphanus sativus interference on soybean cultivars during crop vegetative period

    Directory of Open Access Journals (Sweden)

    N.G. Fleck

    2006-09-01

    Full Text Available A caracterização da habilidade competitiva da soja, em função da resposta diferencial dos cultivares, pode fornecer subsídios valiosos tanto para o melhoramento genético como para o manejo de plantas daninhas. Várias características da cultura podem associar-se com a competitividade; contudo, em soja, poucos estudos foram realizados com a finalidade de identificá-las. Com os objetivos de avaliar a variabilidade existente em cultivares de soja quanto à competitividade com plantas concorrentes e identificar aqueles portadores de habilidade competitiva superior, foi conduzido experimento a campo, em Cruz Alta-RS, na safra 2000/01. Testaram-se duas condições de competição (ausência ou presença de nabo-forrageiro durante a fase de desenvolvimento vegetativo da soja, combinadas com 11 cultivares da cultura. A presença do nabo durante os primeiros 60 dias do ciclo da soja reduziu estatura de planta, área foliar, massa da parte aérea seca, emissão e crescimento de ramos. Os cultivares de soja responderam diferentemente à interferência do nabo, indicando existir variabilidade genética para competitividade, o que permite selecionar genótipos de soja portadores de habilidade competitiva superior. De outra parte, ocorreu maior supressão do crescimento de plantas de nabo em função da presença dos cultivares de soja 'CD 201' e 'Fepagro RS 10'.The characterization of soybean competitive ability, as a function of cultivar differential response, may provide valuable information for genetic crop improvement as well as weed management. Various crop characteristics may be associated with competitivity; however, in soybean, only a few studies have been carried out to identify them. A field experiment was conducted in Cruz Alta-RS during 2000/2001 to evaluate variability in soybean cultivars for competitivity against concurrent plants and to identify those holding superior competitive ability. Two competition conditions were tested

  10. Avaliação da comunicação no espectro autístico: interferência da familiaridade no desempenho de linguagem Assessing communication in the autistic spectrum: interference of familiarity in language performance

    Directory of Open Access Journals (Sweden)

    Camila Ramos Moreira

    2010-01-01

    Full Text Available OBJETIVO: Analisar a interferência da familiaridade da situação de avaliação na funcionalidade da comunicação de sujeitos com diagnóstico incluído no Espectro Autístico, buscando o melhor procedimento para avaliação da comunicação desta população. MÉTODOS: Participaram da presente pesquisa 18 sujeitos com diagnóstico incluído nos Distúrbios do Espectro Autístico, com idades entre três anos e 11 meses e 17 anos e 11 meses, com média etária de oito anos e nove meses (DP: 3,6 anos. Inicialmente foi realizada a filmagem da interação de cada participante com sua terapeuta em situação rotineira de avaliação (Situação Familiar, semelhante às sessões semanais de atendimento, e nas sessões seguintes foi realizada outra filmagem de cada sujeito em interação com uma fonoaudióloga não-familiar, com materiais lúdicos pré-determinados (Situação Não-Familiar. Os dados de interação foram transcritos e analisados e as variáveis foram selecionadas a partir do protocolo do Perfil Funcional da Comunicação (PFC. RESULTADOS: A comparação entre as situações demonstrou diferença apenas para quatro variáveis (23%, dentre as dezessete analisadas; três dessas mostraram resultado superior na Situação Familiar: atos comunicativos expressados por minuto, número de respostas e porcentagem de utilização da função comunicativa Não-Focalizada, e uma delas se mostrou superior na Situação Não-Familiar: porcentagem de utilização da função comunicativa Jogo. CONCLUSÃO: A interferência da familiaridade da situação comunicativa no desempenho comunicativo de sujeitos autistas é mínima, sendo que o procedimento de avaliação nos mesmos moldes da Situação Familiar mostrou-se ligeiramente melhor para a avaliação da comunicação dessa população.PURPOSE: To identify the best technique to assess the communication of autistic spectrum individuals, analyzing the interference of the familiarity of the situation

  11. Small Vessel Security Strategy

    National Research Council Canada - National Science Library

    2008-01-01

    ...), narcotics, aliens, and other contraband, and other criminals. Small vessels have also been successfully employed overseas by terrorists to deliver Waterborne Improvised Explosive Devices (WBIEDs...

  12. Small Intestine Disorders

    Science.gov (United States)

    ... disease Crohn's disease Infections Intestinal cancer Intestinal obstruction Irritable bowel syndrome Ulcers, such as peptic ulcer Treatment of disorders of the small intestine depends on the cause.

  13. Small Wastewater Systems Research

    Science.gov (United States)

    Small communities face barriers to building and maintaining effective wastewater treatment services, challenges include financial/economic limitations, lack of managerial training and geographic isolation/remoteness.

  14. Conservation and diversification of small RNA pathways within flatworms.

    Science.gov (United States)

    Fontenla, Santiago; Rinaldi, Gabriel; Smircich, Pablo; Tort, Jose F

    2017-09-11

    Small non-coding RNAs, including miRNAs, and gene silencing mediated by RNA interference have been described in free-living and parasitic lineages of flatworms, but only few key factors of the small RNA pathways have been exhaustively investigated in a limited number of species. The availability of flatworm draft genomes and predicted proteomes allowed us to perform an extended survey of the genes involved in small non-coding RNA pathways in this phylum. Overall, findings show that the small non-coding RNA pathways are conserved in all the analyzed flatworm linages; however notable peculiarities were identified. While Piwi genes are amplified in free-living worms they are completely absent in all parasitic species. Remarkably all flatworms share a specific Argonaute family (FL-Ago) that has been independently amplified in different lineages. Other key factors such as Dicer are also duplicated, with Dicer-2 showing structural differences between trematodes, cestodes and free-living flatworms. Similarly, a very divergent GW182 Argonaute interacting protein was identified in all flatworm linages. Contrasting to this, genes involved in the amplification of the RNAi interfering signal were detected only in the ancestral free living species Macrostomum lignano. We here described all the putative small RNA pathways present in both free living and parasitic flatworm lineages. These findings highlight innovations specifically evolved in platyhelminths presumably associated with novel mechanisms of gene expression regulation mediated by small RNA pathways that differ to what has been classically described in model organisms. Understanding these phylum-specific innovations and the differences between free living and parasitic species might provide clues to adaptations to parasitism, and would be relevant for gene-silencing technology development for parasitic flatworms that infect hundreds of million people worldwide.

  15. Genome-Wide Identification, Characterization, and Expression Analysis of Small RNA Biogenesis Purveyors Reveal Their Role in Regulation of Biotic Stress Responses in Three Legume Crops

    Directory of Open Access Journals (Sweden)

    Rajeev K. Varshney

    2017-04-01

    Full Text Available Biotic stress in legume crops is one of the major threats to crop yield and productivity. Being sessile organisms, plants have evolved a myriad of mechanisms to combat different stresses imposed on them. One such mechanism, deciphered in the last decade, is small RNA (sRNA mediated defense in plants. Small RNAs (sRNAs have emerged as one of the major players in gene expression regulation in plants during developmental stages and under stress conditions. They are known to act both at transcriptional and post-transcriptional levels. Dicer-like (DCL, Argonaute (AGO, and RNA dependent RNA polymerase (RDR constitute the major components of sRNA biogenesis machinery and are known to play a significant role in combating biotic and abiotic stresses. This study is, therefore, focused on identification and characterization of sRNA biogenesis proteins in three important legume crops, namely chickpea, pigeonpea, and groundnut. Phylogenetic analysis of these proteins between legume species classified them into distinct clades and suggests the evolutionary conservation of these genes across the members of Papillionidoids subfamily. Variable expression of sRNA biogenesis genes in response to the biotic stresses among the three legumes indicate the possible existence of specialized regulatory mechanisms in different legumes. This is the first ever study to understand the role of sRNA biogenesis genes in response to pathogen attacks in the studied legumes.

  16. Comparative Analysis of Fruit Ripening-Related miRNAs and Their Targets in Blueberry Using Small RNA and Degradome Sequencing.

    Science.gov (United States)

    Hou, Yanming; Zhai, Lulu; Li, Xuyan; Xue, Yu; Wang, Jingjing; Yang, Pengjie; Cao, Chunmei; Li, Hongxue; Cui, Yuhai; Bian, Shaomin

    2017-12-19

    MicroRNAs (miRNAs) play vital roles in the regulation of fruit development and ripening. Blueberry is an important small berry fruit crop with economical and nutritional value. However, nothing is known about the miRNAs and their targets involved in blueberry fruit ripening. In this study, using high-throughput sequencing of small RNAs, 84 known miRNAs belonging to 28 families and 16 novel miRNAs were identified in white fruit (WF) and blue fruit (BF) libraries, which represent fruit ripening onset and in progress, respectively. Among them, 41 miRNAs were shown to be differentially expressed during fruit maturation, and 16 miRNAs representing 16 families were further chosen to validate the sRNA sequencing data by stem-loop qRT-PCR. Meanwhile, 178 targets were identified for 41 known and 7 novel miRNAs in WF and BF libraries using degradome sequencing, and targets of miR160 were validated using RLM-RACE (RNA Ligase-Mediated (RLM)-Rapid Amplification of cDNA Ends) approach. Moreover, the expression patterns of 6 miRNAs and their targets were examined during fruit development and ripening. Finally, integrative analysis of miRNAs and their targets revealed a complex miRNA-mRNA regulatory network involving a wide variety of biological processes. The findings will facilitate future investigations of the miRNA-mediated mechanisms that regulate fruit development and ripening in blueberry.

  17. Interferência das plantas daninhas sobre algumas características agronômicas e a produtividade de sete cultivares de milho Weed interference in seven corn cultivars

    Directory of Open Access Journals (Sweden)

    Ivan H. Rossi

    1996-01-01

    Full Text Available O presente trabalho teve por objetivo estudar o comportamento de 7 cultivares de milho (Zea mays L. quanto à interferência da comunidade de plantas daninhas. Para tanto, os 7cultivares de milho (ESALQ VF-7, ESALQ VD-8, COMPOSTOS ARQUITETURA, FLINT e DENTADO, PIRANÃO e o híbrido CARGILL 501 foram submetidos a duas condições de interferência: com e sem, totalizando 14 tratamentos arranjados em esquema fatorial (7x2, instalados, no campo, em área experimental da FCAV/UNESP, Campus de Jaboticabal, seguindo o delineamento experimental de blocos ao acaso com 4 repetições. A comunidade infestante cujas espécies mais importantes foram SIDCO, BRAPL e ELEIN, estabeleceu-se a partir dos 14 dias após a semeadura, passando a interferir negativamente sobre a cultura a partir dos 35 dias. Os cultivares CD e CF apresentaram maior crescimento que os demais. A interferência da comunidade infestante reduziu a altura de inserção da primeira espiga; o comprimento e a circunferência das espigas, os pesos da espigas e dos grãos e a produção estimada da cultura, independente do cultivar. Os cultivares PIR e ARQ, independente da interferência, mostraram-se os menos produtivos. O cultivar Carg mostrou-se o mais produtivo mesmo quando sob interferência. O cultivar ARQ foi o mais sensível à interferência, enquanto PIR e VF-7 foram os menos sensíveis, podendo ser utilizados em programas de melhoramento genético visando tolerância a interferência de plantas daninhas.The present work had as an objective to study the hehavior of seven corn cultivars, according to the inteference of weed plants. So that, the seven corn cultivars (ESALQ VF-7, ESALQ VF-8, COMPOSTOS ARQUITETURA, FLINT E DENTADO, PIRANÃO and CARGILL 501 were submitted to 2 kinds of interference; with na without, totalizing fourteen treatments organized in a factorial plan (7x2, installed in the field as a experimental design of casual blocks with four replications. The infest community

  18. Small Intestine Cancer Treatment

    Science.gov (United States)

    ... all of an organ that contains cancer. The resection may include the small intestine and nearby organs (if the cancer has spread). The doctor may remove the section of the small intestine that contains cancer and perform an anastomosis (joining the cut ends of the intestine together). ...

  19. Small School Reform

    Directory of Open Access Journals (Sweden)

    Carroll E. Bronson

    2013-05-01

    Full Text Available This qualitative ethnographic case study explored the evolution of a public urban high school in its 3rd year of small school reform. The study focused on how the high school proceeded from its initial concept, moving to a small school program, and emerging as a new small high school. Data collection included interviews, observations, and document review to develop a case study of one small high school sharing a multiplex building. The first key finding, “Too Many Pieces, Not Enough Glue,” revealed that the school had too many new programs starting at once and they lacked a clear understanding of their concept and vision for their new small school, training on the Montessori philosophies, teaching and learning in small schools, and how to operate within a teacher-cooperative model. The second key finding, “A Continuous Struggle,” revealed that the shared building space presented problems for teachers and students. District policies remain unchanged, resulting in staff and students resorting to activist approaches to get things done. These findings offer small school reform leaders suggestions for developing and sustaining a small school culture and cohesion despite the pressures to revert back to top-down, comprehensive high school norms.

  20. Industrial Education. "Small Engines".

    Science.gov (United States)

    Parma City School District, OH.

    Part of a series of curriculum guides dealing with industrial education in junior high schools, this guide provides the student with information and manipulative experiences on small gasoline engines. Included are sections on shop adjustment, safety, small engines, internal combustion, engine construction, four stroke engines, two stroke engines,…

  1. Small Business Tax Regimes

    OpenAIRE

    Yilmaz, Fatih; Coolidge, Jacqueline

    2016-01-01

    Simplified tax regimes for micro and small enterprises in developing countries are intended to facilitate voluntary tax compliance. However, survey evidence suggests that small business taxation based on simplified bookkeeping or turnover is sometimes perceived as too complex for microenterprises in countries with high illiteracy levels. Very simple fixed tax regimes not requiring any book...

  2. Novel drug-resistance mechanisms of pemetrexed-treated non-small cell lung cancer.

    Science.gov (United States)

    Tanino, Ryosuke; Tsubata, Yukari; Harashima, Nanae; Harada, Mamoru; Isobe, Takeshi

    2018-03-30

    Pemetrexed (PEM) improves the overall survival of patients with advanced non-small cell lung cancer (NSCLC) when administered as maintenance therapy. However, PEM resistance often appears during the therapy. Although thymidylate synthase is known to be responsible for PEM resistance, no other mechanisms have been investigated in detail. In this study, we explored new drug resistance mechanisms of PEM-treated NSCLC using two combinations of parental and PEM-resistant NSCLC cell lines from PC-9 and A549. PEM increased the apoptosis cells in parental PC-9 and the senescent cells in parental A549. However, such changes were not observed in the respective PEM-resistant cell lines. Quantitative RT-PCR analysis revealed that, besides an increased gene expression of thymidylate synthase in PEM-resistant PC-9 cells, the solute carrier family 19 member1 ( SLC19A1) gene expression was markedly decreased in PEM-resistant A549 cells. The siRNA-mediated knockdown of SLC19A1 endowed the parental cell lines with PEM resistance. Conversely, PEM-resistant PC-9 cells carrying an epidermal growth factor receptor (EGFR) mutation acquired resistance to a tyrosine kinase inhibitor erlotinib. Although erlotinib can inhibit the phosphorylation of EGFR and Erk, it is unable to suppress the phosphorylation of Akt in PEM-resistant PC-9 cells. Additionally, PEM-resistant PC-9 cells were less sensitive to the PI3K inhibitor LY294002 than parental PC-9 cells. These results indicate that SLC19A1 negatively regulates PEM resistance in NSCLC, and that EGFR-tyrosine-kinase-inhibitor resistance was acquired with PEM resistance through Akt activation in NSCLC harboring EGFR mutations.

  3. Unraveling multifaceted contributions of small regulatory RNAs to photomorphogenic development in Arabidopsis.

    Science.gov (United States)

    Lin, Meng-Chun; Tsai, Huang-Lung; Lim, Sim-Lin; Jeng, Shih-Tong; Wu, Shu-Hsing

    2017-07-24

    Post-transcriptional control of gene expression mediated by small regulatory RNAs (sRNAs) is vital for growth and development of diverse organisms. The biogenesis of sRNAs is regulated by both positive and negative regulators known to regulate photomorphogenic development. Two microRNAs (miRNAs), miR157 and miR319, also regulate photomorphogenesis. However, genome-wide profiling of sRNAs and their regulation of target genes during photomorphogenesis has been missing. We provide a comprehensive view of sRNA-controlled gene expression in this developmental process. By profiling sRNAs and the 5' ends of degraded mRNAs during the first 24 h of photomorphogenic development in Arabidopsis, we identified 335 sRNA-mediated mRNA cleavage events in de-etiolating seedlings. These cleavage events are primarily resulted from actions of highly expressed miRNAs and irrelevant to the abundance of target mRNAs. In the light, the expression of the slicer protein gene ARGONAUTE1 in the miRNA functioning pathway could be fine-tuned by miRNA168a/b. We also found that miR396a/b positively regulates de-etiolation by suppressing GROWTH REGULATING FACTORs. Our results suggest that the miRNAs are required to tune down the target mRNAs and regulate photomorphogenesis. sRNAs may have a broad impact on gene expression regulation for optimized photomorphogenic development. With both positive and negative regulators under the control of sRNAs, young Arabidopsis seedlings can have a timely but not exaggerated developmental adaptation to light.

  4. Antiviral activity of a small molecule deubiquitinase inhibitor occurs via induction of the unfolded protein response.

    Directory of Open Access Journals (Sweden)

    Jeffrey W Perry

    Full Text Available Ubiquitin (Ub is a vital regulatory component in various cellular processes, including cellular responses to viral infection. As obligate intracellular pathogens, viruses have the capacity to manipulate the ubiquitin (Ub cycle to their advantage by encoding Ub-modifying proteins including deubiquitinases (DUBs. However, how cellular DUBs modulate specific viral infections, such as norovirus, is poorly understood. To examine the role of DUBs during norovirus infection, we used WP1130, a small molecule inhibitor of a subset of cellular DUBs. Replication of murine norovirus in murine macrophages and the human norovirus Norwalk virus in a replicon system were significantly inhibited by WP1130. Chemical proteomics identified the cellular DUB USP14 as a target of WP1130 in murine macrophages, and pharmacologic inhibition or siRNA-mediated knockdown of USP14 inhibited murine norovirus infection. USP14 is a proteasome-associated DUB that also binds to inositol-requiring enzyme 1 (IRE1, a critical mediator of the unfolded protein response (UPR. WP1130 treatment of murine macrophages did not alter proteasome activity but activated the X-box binding protein-1 (XBP-1 through an IRE1-dependent mechanism. In addition, WP1130 treatment or induction of the UPR also reduced infection of other RNA viruses including encephalomyocarditis virus, Sindbis virus, and La Crosse virus but not vesicular stomatitis virus. Pharmacologic inhibition of the IRE1 endonuclease activity partially rescued the antiviral effect of WP1130. Taken together, our studies support a model whereby induction of the UPR through cellular DUB inhibition blocks specific viral infections, and suggest that cellular DUBs and the UPR represent novel targets for future development of broad spectrum antiviral therapies.

  5. Desenvolvimento da cultura de mandioca sob interferência de plantas daninhas Weed interference in the development of the cassava plant

    Directory of Open Access Journals (Sweden)

    J.A.A. Albuquerque

    2012-03-01

    Full Text Available Um dos fatores que afetam o desenvolvimento da planta da mandioca é o controle inadequado das plantas daninhas. Objetivou-se com este trabalho avaliar o desenvolvimento da cultura de mandioca sob interferência de plantas daninhas. Foram realizados dois experimentos: no primeiro, os tratamentos foram compostos por períodos de convivência da cultura da mandioca com as plantas daninhas por 25, 50, 75, 100 e 125 dias após plantio e, no segundo, as plantas de mandioca permaneceram livres das plantas daninhas pelos mesmos períodos preestabelecidos. Avaliações de altura de plantas e diâmetro de caule foram realizadas aos 75, 100, 125, 150, 175, 200, 225, 250, 275, 300, 325 e 350 dias após o plantio. Nas colheitas dos experimentos, realizadas aos 330 dias após plantio, avaliou-se o número e o diâmetro das raízes por planta. A convivência por intervalo igual ou superior a 50 dias após o plantio reduziu o diâmetro de caule e a altura das plantas de mandioca, assim como o número e comprimento de raízes tuberosas. O controle das plantas daninhas nessa cultura deve ser iniciado em torno de 25 dias após o plantio.One of the factors affecting the development of the cassava plant is the inadequate control of weeds. Thus, this work aimed to evaluate the development of the cassava plant under weed interference during different coexistence periods. Two experiments were installed in adjacent areas, in Viçosa, Minas Gerais - Brazil. In the first experiment, the treatments consisted of different periods of coexistence between the cassava culture and the weeds (25, 50, 75, 100 and 125 days after planting. In the second experiment, the cassava plants remained weed-free for the same pre-established periods. For both experiments, the 1.0 x 0.5 m spacing was adopted, being the useful portion area constituted by the two central lines, with 1.0 m being left at each extremity as front borders, adding 8.0 m2 up. Plant height and stem diameter were

  6. SmallSat Database

    Science.gov (United States)

    Petropulos, Dolores; Bittner, David; Murawski, Robert; Golden, Bert

    2015-01-01

    The SmallSat has an unrealized potential in both the private industry and in the federal government. Currently over 70 companies, 50 universities and 17 governmental agencies are involved in SmallSat research and development. In 1994, the U.S. Army Missile and Defense mapped the moon using smallSat imagery. Since then Smart Phones have introduced this imagery to the people of the world as diverse industries watched this trend. The deployment cost of smallSats is also greatly reduced compared to traditional satellites due to the fact that multiple units can be deployed in a single mission. Imaging payloads have become more sophisticated, smaller and lighter. In addition, the growth of small technology obtained from private industries has led to the more widespread use of smallSats. This includes greater revisit rates in imagery, significantly lower costs, the ability to update technology more frequently and the ability to decrease vulnerability of enemy attacks. The popularity of smallSats show a changing mentality in this fast paced world of tomorrow. What impact has this created on the NASA communication networks now and in future years? In this project, we are developing the SmallSat Relational Database which can support a simulation of smallSats within the NASA SCaN Compatability Environment for Networks and Integrated Communications (SCENIC) Modeling and Simulation Lab. The NASA Space Communications and Networks (SCaN) Program can use this modeling to project required network support needs in the next 10 to 15 years. The SmallSat Rational Database could model smallSats just as the other SCaN databases model the more traditional larger satellites, with a few exceptions. One being that the smallSat Database is designed to be built-to-order. The SmallSat database holds various hardware configurations that can be used to model a smallSat. It will require significant effort to develop as the research material can only be populated by hand to obtain the unique data

  7. Wind: small is beautiful

    International Nuclear Information System (INIS)

    Vries, E. de

    2005-01-01

    The small wind sector (0.5-100 kW) is often overlooked but could provide decentralised energy systems. Small wind turbines have been used for homes, farms and small businesses for over 80 years (e.g. in the USA and the Netherlands), receiving a boost in the 1970s and 1980s following the 1973 oil crisis when a new generation of turbines entered the European and US markets. Bergey Windpower and Southwest Windpower from the USA are the market leaders in this sector in terms of sales volume but are still classed as medium-sized enterprises. Small turbines have the disadvantage of higher costs compared with large turbines due to higher manufacturing costs, technical factors associated with the tendency to use small turbines on relatively short towers, small production runs and a failure to keep up with the latest design developments such as cost-effective state-of-the-art frequency converters. Most small turbines are horizontal axis turbines, though vertical axis turbines are produced by some manufacturers. Examples of the systems available from European suppliers are described

  8. 78 FR 11745 - Small Business Size Regulations, Small Business Innovation Research (SBIR) Program and Small...

    Science.gov (United States)

    2013-02-20

    ..., Small Business Innovation Research (SBIR) Program and Small Business Technology Transfer (STTR) Program... Innovation Research (SBIR) and Small Business Technology Transfer (STTR) programs. DATES: Effective February...

  9. Small scale optics

    CERN Document Server

    Yupapin, Preecha

    2013-01-01

    The behavior of light in small scale optics or nano/micro optical devices has shown promising results, which can be used for basic and applied research, especially in nanoelectronics. Small Scale Optics presents the use of optical nonlinear behaviors for spins, antennae, and whispering gallery modes within micro/nano devices and circuits, which can be used in many applications. This book proposes a new design for a small scale optical device-a microring resonator device. Most chapters are based on the proposed device, which uses a configuration know as a PANDA ring resonator. Analytical and nu

  10. Small - Display Cartography

    DEFF Research Database (Denmark)

    Nissen, Flemming; Hvas, Anders; Münster-Swendsen, Jørgen

    This report comprises the work carried out in the work-package of small display cartography. The work-package has aimed at creating a general framework for the small-display cartography. A solid framework facilitates an increased use of spatial data in mobile devices - thus enabling, together...... Service Communication and finally, Part IV: Concluding remarks and topics for further research on small-display cartography. Part II includes a separate Appendix D consisting of a cartographic design specification. Part III includes a separate Appendix C consisting of a schema specification, a separate...

  11. Small satellite product assurance

    Science.gov (United States)

    Demontlivault, J.; Cadelec, Jacques

    1993-01-01

    In order to increase the interest in small satellites, their cost must be reduced; reducing product assurance costs induced by quality requirements is a major objective. For a logical approach, small satellites are classified in three main categories: satellites for experimental operations with a short lifetime, operational satellites manufactured in small mass with long lifetime requirements, operational satellites (long lifetime required), of which only a few models are produced. The various requirements as regards the product assurance are examined for each satellite category: general requirements for space approach, reliability, electronic components, materials and processes, quality assurance, documentation, tests, and management. Ideal product assurance system integrates quality teams and engineering teams.

  12. Lightweight Small Arms Technologies

    National Research Council Canada - National Science Library

    Spiegel, Kori; Shipley, Paul

    2006-01-01

    .... The Lightweight Small Arms Technologies program was established to address this critical issue. The goals of the program prioritize weight reduction over any other characteristic, while balancing the requirements of lethality, reliability, and cost...

  13. The Power of Small

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 20; Issue 12. The Power of Small: Championing the Underdogs of Modern Medicine. Suvasini Ramaswamy Anirban Mitra. General Article Volume 20 Issue 12 December 2015 pp 1136-1153 ...

  14. Small Satellite Transporter Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The primary objective is to determine whether this small satellite transporter is capable of transporting at least four 6U CubeSats is possible for a given set of...

  15. Small bowel bacterial overgrowth

    Science.gov (United States)

    ... Surgical procedures that create a loop of small intestine where excess bacteria can grow. An example is a Billroth II type of stomach removal ( gastrectomy ). Some cases of irritable bowel syndrome (IBS).

  16. Small-x physics

    Energy Technology Data Exchange (ETDEWEB)

    Mueller, A.H. [Columbia Univ., New York, NY (United States). Dept. of Physics

    1997-06-01

    After a brief review of the kinematics of deep inelastic lepton-proton scattering, the parton model is described. Small-x behavior coming from DGLAP evolution and from BFKL evolution is discussed, and the two types of evolution are contrasted and compared. Then a more detailed discussion of BFKL dynamics is given. The phenomenology of small-x physics is discussed with an emphasis on ways in which BFKL dynamics may be discussed and measured. 45 refs., 12 figs.

  17. Small - Display Cartography

    OpenAIRE

    Nissen, Flemming; Hvas, Anders; Münster-Swendsen, Jørgen; Brodersen, Lars

    2003-01-01

    This report comprises the work carried out in the work-package of small display cartography. The work-package has aimed at creating a general framework for the small-display cartography. A solid framework facilitates an increased use of spatial data in mobile devices - thus enabling, together with the rapidly evolving positioning techniques, a new category of position-dependent, map-based services to be introduced. The report consists of the following parts: Part I: Categorization of handheld...

  18. Research using small tokamaks

    International Nuclear Information System (INIS)

    1989-07-01

    These proceedings of the IAEA-sponsored meeting held in Nice, France 10-11 October, 1988, contain the manuscripts of the 21 reports dealing with research using small tokamaks. The purpose of this meeting was to highlight some of the achievements of small tokamaks and alternative magnetic confinement concepts and assess the suitability of starting new programs, particularly in developing countries. Papers presented were either review papers, or were detailed descriptions of particular experiments or concepts. Refs, figs and tabs

  19. Small test SDHW systems

    DEFF Research Database (Denmark)

    Vejen, Niels Kristian

    1999-01-01

    Three small test SDHW systems was tested in a laboratory test facility.The three SDHW systems where all based on the low flow principe and a mantle tank but the design of the systems where different.......Three small test SDHW systems was tested in a laboratory test facility.The three SDHW systems where all based on the low flow principe and a mantle tank but the design of the systems where different....

  20. Small wind turbine

    OpenAIRE

    Vélez Castellano, Didier

    2010-01-01

    The main objective is to develop a project on installing a small wind turbine at the University of Glyndwr in Wrexham Wales. Today are immersed in a world seeking clean energy for reduce greenhouse gases because this problem is becoming a global reality. So installing a small wind turbine at the university would provide large quantity of clean energy to supply a workshop and also reduce the expulsion of CO2 into the atmosphere. The main characteristic of the turbine under...

  1. Small woodland ownership management

    Science.gov (United States)

    Albert J. Childs

    1977-01-01

    Small woodlot ownerships are a commodity on the real estate market which have cycled through a supply and demand curve on a somewhat irregular basis. In order to have some understanding of what it is we are talking about, it is necessary to define what a small woodlot is, and where it may be found. In size these parcels can range from ten acres to fifteen acres on up...

  2. Períodos de interferência de Brachiaria plantaginea na cultura do milho na região Sul do Rio Grande do Sul Interference periods of Brachiaria plantaginea in corn crops in Southern Rio Grande do Sul

    Directory of Open Access Journals (Sweden)

    L. Galon

    2008-01-01

    Full Text Available Os períodos de convivência das espécies daninhas têm grande influência no crescimento das plantas e na produtividade das culturas. Desse modo, objetivou-se com este trabalho determinar os períodos de competição, anterior à interferência (PAI, o crítico de prevenção à interferência (PCPI e o período total de prevenção da interferência (PTPI de B. plantaginea sobre a cultura do milho na Região Sul do Rio Grande do Sul. Adotou-se o delineamento experimental de blocos casualizados, no sistema de cultivo convencional com quatro repetições. Os tratamentos consistiram em manter a cultura do milho na presença e ausência de B. plantaginea por 0, 7, 14, 21, 28, 35 e 42 dias após a emergência (DAE da cultura. B. plantaginea originou-se do banco de sementes do solo, com população média de 312 plantas m-2. Foram amostradas e analisadas 10 plantas de milho em cada unidade experimental, com vistas à avaliação da altura de plantas e da inserção da espiga (cm, do comprimento de espigas (cm, do número de fileiras por espiga, número de grãos por fileira e número de grãos por espiga, além da produtividade de grãos, que foi determinada pela colheita de três linhas centrais da área útil em cada unidade experimental. Considerando 5% de tolerância na redução da produção, conclui-se que o período total de prevenção à interferência (PTPI foi de 27 DAE; o período que antecede a interferência (PAI, de 11 DAE; e o período crítico de prevenção à interferência (PCPI, de 11 a 27 DAE.Weed control period have great influence on plant growth and crop productivity. The objective of this work was to determine the competition periods, both previous to interference and critical interference prevention of B. plantaginea on corn crop in Southern Rio Grande do Sul. The trial was conducted in a completely randomized block design, under conventional tillage system, with four replications. The treatments consisted of maintaining

  3. How small is a small cloud?

    Directory of Open Access Journals (Sweden)

    I. Koren

    2008-07-01

    Full Text Available The interplay between clouds and aerosols and their contribution to the radiation budget is one of the largest uncertainties of climate change. Most work to date has separated cloudy and cloud-free areas in order to evaluate the individual radiative forcing of aerosols, clouds, and aerosol effects on clouds.

    Here we examine the size distribution and the optical properties of small, sparse cumulus clouds and the associated optical properties of what is considered a cloud-free atmosphere within the cloud field. We show that any separation between clouds and cloud free atmosphere will incur errors in the calculated radiative forcing.

    The nature of small cumulus cloud size distributions suggests that at any resolution, a significant fraction of the clouds are missed, and their optical properties are relegated to the apparent cloud-free optical properties. At the same time, the cloudy portion incorporates significant contribution from non-cloudy pixels.

    We show that the largest contribution to the total cloud reflectance comes from the smallest clouds and that the spatial resolution changes the apparent energy flux of a broken cloudy scene. When changing the resolution from 30 m to 1 km (Landsat to MODIS the average "cloud-free" reflectance at 1.65 μm increases from 0.0095 to 0.0115 (>20%, the cloud reflectance decreases from 0.13 to 0.066 (~50%, and the cloud coverage doubles, resulting in an important impact on climate forcing estimations. The apparent aerosol forcing is on the order of 0.5 to 1 Wm−2 per cloud field.

  4. Horizontal Transfer of Small RNAs To and From Plants

    Directory of Open Access Journals (Sweden)

    Lu eHan

    2015-12-01

    Full Text Available Genetic information is traditionally thought to be transferred from parents to offspring. However, there is evidence indicating that gene transfer can also occur from microbes to higher species, such as plants, invertebrates and vertebrates. This horizontal transfer can be carried out by small RNAs (sRNAs. sRNAs have been recently reported to move across kingdoms as mobile signals, spreading silencing information toward targeted genes. sRNAs, especially microRNAs (miRNAs and small interfering RNAs (siRNAs, are non-coding molecules that control gene expression at the transcriptional or post-transcriptional level. Some sRNAs act in a cross-kingdom manner between animals and their parasites, but little is known about such sRNAs associated with plants. In this report, we provide a brief introduction to miRNAs that are transferred from plants to mammals/viruses and siRNAs that are transferred from microbes to plants. Both miRNAs and siRNAs can exert corresponding functions in the target organisms. Additionally, we provide information concerning a host-induced gene silencing (HIGS system as a potential application that utilizes the transgenic trafficking of RNA molecules to silence the genes of interacting organisms. Moreover, we lay out the controversial views regarding cross-kingdom miRNAs and call for better methodology and experimental design to confirm this unique function of miRNAs.

  5. Small RNA Deep Sequencing Reveals Role for Arabidopsis thaliana RNA-Dependent RNA Polymerases in Viral siRNA Biogenesis

    OpenAIRE

    Qi, Xiaopeng; Bao, Forrest Sheng; Xie, Zhixin

    2009-01-01

    RNA silencing functions as an important antiviral defense mechanism in a broad range of eukaryotes. In plants, biogenesis of several classes of endogenous small interfering RNAs (siRNAs) requires RNA-dependent RNA Polymerase (RDR) activities. Members of the RDR family proteins, including RDR1and RDR6, have also been implicated in antiviral defense, although a direct role for RDRs in viral siRNA biogenesis has yet to be demonstrated. Using a crucifer-infecting strain of Tobacco Mosaic Virus (T...

  6. As interferências das pisciculturas em tanques-rede a assembléia de peixe em grandes reservatórios do rio paranapanema (Bacia doAlto Paraná)

    OpenAIRE

    Zanatta, Augusto Seawright [UNESP

    2011-01-01

    Atualmente, a filosofia da sustentabilidade ambiental que foca a preocupação com o uso racional dos recursos hídricos e pesqueiros, em particular a aqüicultura, está aumentando em nossa sociedade. Portanto, é preciso empregar esforços compatibilizando processos antagônicos da produção de alimento versus preservação ambiental. Neste contexto, o presente trabalho objetivou avaliar as possíveis interferências ambientais (limnológicas e ictiológicas) de um empreendimento de tilapicultura em tanqu...

  7. Total period of weed interference prevention in lettuce cv. SolarisPeríodo total de prevenção a interferência das plantas daninhas na cultura da alface cultivar Solaris

    Directory of Open Access Journals (Sweden)

    Micheli Satomi Yamauti

    2010-02-01

    Full Text Available This research work aimed to determine the total period of interference of weeds prevention of lettuce cultivar Solaris. The experiment was conducted in Universidade Estadual de Londrina, in the period of autumn/ winter of 2008. The lettuce crop remained free from weed interference from emergence up to 0, 10, 20, 30, 40, 50 e 60 days. The experiment was arranged in a randomized block design with four replications. The weed community was composed by Bidens pilosa, Amaranthus hybridus, Oxalis corniculata, Euphorbia heterophylla, Spinacia oleracea, Commelina benghalensis e Lepidium virginicum. It was determined dry and fresh matter of weeds, and number of lettuce leaves. Assuming a tolerance of 5% for crop production decrease, it was verified that the total period of interference prevention (TPIP occurred up to 21 days after transplanting. Weed interference throughout the crop cycle reduced 25% of its yield.Este trabalho foi realizado com o objetivo de determinar o período total de prevenção à interferência (PTPI das plantas daninhas na cultura da alface do tipo crespa, cultivar Solaris. O experimento foi instalado na Universidade Estadual de Londrina, no período de outono/ inverno de 2008. A cultura permaneceu livre da interferência das plantas daninhas desde o transplante até: 0, 10, 20, 30, 40, 50 e 60 dias. O delineamento utilizado foi o de blocos casualizados com quatro repetições. A comunidade infestante da área foi composta principalmente de Bidens pilosa, Amaranthus hybridus, Oxalis corniculata, Euphorbia heterophylla, Spinacia oleracea, Commelina benghalensis e Lepidium virginicum. As massas seca e fresca das plantas daninhas e o número de folhas da cultura foram determinados. Admitindo-se 5% de tolerância na redução da produtividade da cultura, o período total de prevenção à interferência (PTPI ocorreu 21 dias após o transplante. A interferência das plantas daninhas durante todo o ciclo de vida da alface reduziu a

  8. Interferência de plantas daninhas sobre o crescimento inicial de Coffea arabica Weed effect on the initial growth of Coffea arabica

    Directory of Open Access Journals (Sweden)

    C.M.T. Fialho

    2011-03-01

    Full Text Available Objetivou-se com este trabalho avaliar os efeitos da interferência de plantas daninhas, em diferentes densidades de infestação, sobre o crescimento de plantas jovens de café arábica. Mudas de café, cultivar Mundo Novo, foram transplantadas, no estádio de quatro a cinco pares de folhas completamente expandidas, para vasos com capacidade de 25 dm³. O experimento foi conduzido em casa de vegetação em blocos casualizados, em esquema fatorial (4 x 4; o primeiro fator foi composto por espécies de plantas daninhas (Digitaria horizontalis, Brachiaria decumbens, Brachiaria plantaginea e Mucuna aterrima, e o segundo, por densidades dessas espécies (zero, dois, quatro e seis plantas por vaso, com quatro repetições. O plantio das espécies daninhas foi realizado 60 dias após o transplantio do café (0 DAT. Nesta data e no dia do encerramento do experimento, aos 90 DAT, determinaram-se a altura, a área foliar e o diâmetro do caule da planta de café, para cálculo do incremento dessas variáveis. Aos 90 DAT, determinou-se a matéria seca da parte aérea e radicular do café e das plantas daninhas e a densidade radicular do café. Utilizando esses resultados, estimou-se a razão de massa foliar, razão de massa caulinar, razão de massa radicular, razão de área foliar e a razão sistema radicular/parte aérea das plantas de café. A espécie M. aterrima foi a que mais reduziu a taxa de crescimento, a área foliar, a matéria seca do caule e das folhas e o diâmetro do caule do café. Entre as gramíneas, B. plantaginea foi a que mais reduziu a taxa de crescimento, área foliar, diâmetro do caule e densidade radicular do café. Ocorreu relação negativa entre a densidade de plantas daninhas e as variáveis de crescimento e com a razão de massa radicular e razão sistema radicular/parte aérea.The goal of this work was to evaluate the effects of weeds on the growth of young Arabica coffee plants, at different densities of infestation

  9. Small intestine and microbiota.

    Science.gov (United States)

    Cotter, Paul D

    2011-03-01

    To highlight the recent studies which have enhanced our appreciation of the composition of the microbiota in the human small intestine and its relevance to the health of the host. In the past number of years, the composition of the microorganisms present in our small intestines has been the subject of greater scrutiny than ever before. These investigations have been possible as a consequence of the development and utilization of new molecular tools which have revolutionized the field of microbial ecology and have focused predominantly on the small intestinal microbiota associated with pediatric celiac disease, inflammatory bowel disease, irritable bowel syndrome and pouchitis. The impact of invasive procedures, such as small bowel transplant, ileostomy and ileal pouch anal anastomosis, on the ileal microbiota has also been investigated. The ever greater appreciation of the link between the small intestinal microbiota and the health status of the host has the potential to lead to the development of new strategies to alter this microbiota in a targeted way to prevent or treat specific disorders.

  10. Small intestine diverticuli

    International Nuclear Information System (INIS)

    Pomakov, P.; Risov, A.

    1991-01-01

    The routine method of contrast matter passage applied to 850 patients with different gastrointestinal diseases proved inefficient to detect any small-intestinal diverticuli. The following modiffications of the method have been tested in order to improve the diagnostic possibilities of the X-ray: study at short intervals, assisted passage, enteroclysm, pharmacodynamic impact, retrograde filling of the ileum by irrigoscopy. Twelve diverticuli of the small-intestinal loops were identified: 5 Meckel's diverticuli, 2 solitary of which one of the therminal ileum, 2 double diverticuli and 1 multiple diverticulosis of the jejunum. The results show that the short interval X-ray examination of the small intestines is the method of choice for identifying local changes in them. The solitary diverticuli are not casuistic scarcity, its occurrence is about 0.5% at purposeful X-ray investigation. The assisted passage method is proposed as a method of choice for detection of the Meckel's diverticulum. 5 figs., 3 tabs. 18 refs

  11. Small public private partnerships

    DEFF Research Database (Denmark)

    Koch, Christian; Jensen, Jesper Ole

    2009-01-01

    businesses and represent operable units for the clients and citizens. Cases are focused within education and healthcare. The analysis suggests that another type of economy apparently is in play. It is thus characteristic within education projects in UK that the largest portion of small PPPs are of a size......Public Private Partnerships (PPP) are frequently mobilized as a purchasing form suitable for large infrastructure projects. And it is commonly assumed that transaction costs linked to the establishment of PPP make them prohibitive in small sizes. In a Danish context this has been safeguarded...... by the authorities, which recommend sizes over 13,5 million € (100 million DKr). PPP is here understood as Design, Build, Finance and Operate projects. The paper shows, when looking at Germany, Italy and United Kingdom, that small PPP (below 13,5 million €) are widespread in two investigated countries; United...

  12. Small Intestinal Infections.

    Science.gov (United States)

    Munot, Khushboo; Kotler, Donald P

    2016-06-01

    Small intestinal infections are extremely common worldwide. They may be bacterial, viral, or parasitic in etiology. Most are foodborne or waterborne, with specific etiologies differing by region and with diverse pathophysiologies. Very young, very old, and immune-deficient individuals are the most vulnerable to morbidity or mortality from small intestinal infections. There have been significant advances in diagnostic sophistication with the development and early application of molecular diagnostic assays, though these tests have not become mainstream. The lack of rapid diagnoses combined with the self-limited nature of small intestinal infections has hampered the development of specific and effective treatments other than oral rehydration. Antibiotics are not indicated in the absence of an etiologic diagnosis, and not at all in the case of some infections.

  13. Small hydro in Africa

    CSIR Research Space (South Africa)

    Jonker Klunne, W

    2011-10-01

    Full Text Available the gold mines at Pilgrim?s Rest in South Africa were powered by two 6kW hydro turbines as early as 1892, complemented by a 45kW turbine in 1894 to power the first electrical railway. In several African countries church missions built small hydro... that feed in to the national grid as this ensures a steady income stream for the enterprise. Several African countries have established renewable energy feed-in tariffs (Kenya, South Africa and Uganda) that do support the establishment of small scale...

  14. Small finance banks: Challenges

    Directory of Open Access Journals (Sweden)

    Jayadev M

    2017-12-01

    Full Text Available A recent innovation in the Indian banking structure has been the formation of a new banking institution—small finance banks (SFBs. These banks are expected to penetrate into financial inclusion by providing basic banking and credit services with a differentiated banking model to the larger population. In this context the new SFBs have multiple challenges in coming out with a new, differentiated business model. The challenges include building low cost liability portfolio, technology management, and balancing the regulatory compliances. This paper also presents the top of mind views of three senior executives of new small finance banks.

  15. Small hydroelectric engineering practice

    CERN Document Server

    Leyland, Bryan

    2014-01-01

    Small Hydroelectric Engineering Practice is a comprehensive reference book covering all aspects of identifying, building, and operating hydroelectric schemes between 500 kW and 50 MW. In this range of outputs there are many options for all aspects of the scheme and it is very important that the best options are chosen.As small hydroelectric schemes are usually built against a limited budget it is extremely important that the concept design is optimum and every component is designed to maximise the benefi t and minimise the cost. As operating costs are often a high proportion of the income it i

  16. Small Column Ion Exchange

    International Nuclear Information System (INIS)

    Huff, Thomas

    2010-01-01

    Small Column Ion Exchange (SCIX) leverages a suite of technologies developed by DOE across the complex to achieve lifecycle savings. Technologies are applicable to multiple sites. Early testing supported multiple sites. Balance of SRS SCIX testing supports SRS deployment. A forma Systems Engineering Evaluation (SEE) was performed and selected Small Column Ion Exchange columns containing Crystalline Silicotitanate (CST) in a 2-column lead/lag configuration. SEE considered use of Spherical Resorcinol-Formaldehyde (sRF). Advantages of approach at SRS include: (1) no new buildings, (2) low volume of Cs waste in solid form compared to aqueous strip effluent; and availability of downstream processing facilities for immediate processing of spent resin.

  17. A Small Indel Mutant Mouse Model of Epidermolytic Palmoplantar Keratoderma and Its Application to Mutant-specific shRNA Therapy

    Directory of Open Access Journals (Sweden)

    Ya-Su Lyu

    2016-01-01

    Full Text Available Epidermolytic palmoplantar keratoderma (EPPK is a relatively common autosomal-dominant skin disorder caused by mutations in the keratin 9 gene (KRT9, with few therapeutic options for the affected so far. Here, we report a knock-in transgenic mouse model that carried a small insertion–deletion (indel mutant of Krt9, c.434delAinsGGCT (p.Tyr144delinsTrpLeu, corresponding to the human mutation KRT9/c.500delAinsGGCT (p.Tyr167delinsTrpLeu, which resulted in a human EPPK-like phenotype in the weight-stress areas of the fore- and hind-paws of both Krt9+/mut and Krt9mut/mut mice. The phenotype confirmed that EPPK is a dominant-negative condition, such that mice heterozygotic for the K9-mutant allele (Krt9+/mut showed a clear EPPK-like phenotype. Then, we developed a mutant-specific short hairpin RNA (shRNA therapy for EPPK mice. Mutant-specific shRNAs were systematically identified in vitro using a luciferase reporter gene assay and delivered into Krt9+/mut mice. shRNA-mediated knockdown of mutant protein resulted in almost normal morphology and functions of the skin, whereas the same shRNA had a negligible effect in wild-type K9 mice. Our results suggest that EPPK can be treated by gene therapy, and this has significant implications for future clinical application.

  18. Coxsackie-adenovirus receptor as a novel marker of stem cells in treatment-resistant non-small cell lung cancer.

    Science.gov (United States)

    Zhang, Xiaochun; Fang, Bingliang; Mohan, Radhe; Chang, Joe Y

    2012-11-01

    Treatment resistance resulting from the presence of cancer stem cells (CSCs) remains a challenge in cancer treatment. Little is known about possible markers of CSCs in treatment-resistant non-small cell lung cancer (NSCLC). We explored the coxsackie-adenovirus receptor (CAR) as one such marker of CSCs in models of treatment-resistant NSCLC. Resistant H460 and A549 cell lines were established by repeated exposure to paclitaxel or fractionated radiation. CSC markers were measured by Western blotting and flow cytometry. We also established stable CAR-overexpressing and stable shRNA-CAR-knockdown cell lines and assessed their survival, invasiveness, and tumorigenic capabilities with clonogenic, telomerase, Matrigel, and tumor formation assays. CAR expression was associated with CSC phenotype both in vitro and in vivo. CAR-overexpressing cells were more treatment-resistant, self-renewing, and tumorigenic than were parental cells, and shRNA-mediated knockdown of CAR expression was sufficient to inhibit these functions. CAR expression also correlated with the epithelial-mesenchymal transition. We showed for the first time that CAR is a marker of CSCs and may affect the activities of CSCs in treatment-resistant NSCLC. CAR may prove to be a target for CSC treatment and a predictor of treatment response in patients with NSCLC. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  19. Coxsackie- and adenovirus receptor as a novel marker of stem cells in treatment-resistant non-small cell lung cancer

    Science.gov (United States)

    Zhang, Xiaochun; Fang, Bingliang; Mohan, Radhe; Chang, Joe Y.

    2013-01-01

    Background Treatment resistance resulting from the presence of cancer stem cells (CSCs) remains a challenge in cancer treatment. Little is known about possible markers of CSCs in treatment-resistant non-small cell lung cancer (NSCLC). We explored the coxsackie- and adenovirus receptor (CAR) as one such marker of CSCs in models of treatment-resistant NSCLC. Materials and methods Resistant H460 and A549 cell lines were established by repeated exposure to paclitaxel or fractionated radiation. CSC markers were measured by western blotting and flow cytometry. We also established stable CAR-overexpressing and stable shRNA-CAR-knockdown cell lines and assessed their survival, invasiveness, and tumorigenic capabilities with clonogenic, telomerase, Matrigel, and tumor formation assays. Results CAR expression was associated with CSC phenotype both in vitro and in vivo. CAR-overexpressing cells were more treatment-resistant, self-renewing, and tumorigenic than were parental cells, and shRNA-mediated knockdown of CAR expression was sufficient to inhibit these functions. CAR expression also correlated with the epithelial-mesenchymal transition. Conclusions We showed for the first time that CAR is a marker of CSCs and may affect the activities of CSCs in treatment-resistant NSCLC. CAR may prove to be a target for CSC treatment and a predictor of treatment response in patients with NSCLC. PMID:23022172

  20. How Small are Small Stars Really?

    Science.gov (United States)

    2002-11-01

    VLT Interferometer Measures the Size of Proxima Centauri and Other Nearby Stars [1] Summary At a distance of only 4.2 light-years, Proxima Centauri is the nearest star to the Sun currently known [2]. It is visible as an 11-magnitude object in the southern constellation of Centaurus and is the faintest member of a triple system, together with Alpha Centauri , the brightest (double) star in this constellation. Proxima Centauri is a very-low-mass star, in fact barely massive enough to burn hydrogen to helium in its interior. It is about seven times smaller than the Sun, and the surface temperature is "only" about 3000 degrees, about half of that of our own star. Consequently, it is also much fainter - the intrinsic brightness is only 1/150th of that of our Sun. Low-mass stars are very interesting objects , also because the physical conditions in their interiors have much in common with those of giant planets, like Jupiter in our solar system. A determination of the sizes of the smallest stars has been impossible until now because of their general faintness and lack of adequate instrumentation. However, astronomers have long been keen to move forward in this direction, since such measurements would provide indirect, crucial information about the behaviour of matter under extreme conditions. When the first observations with the VLT Interferometer (VLTI), combining the light from two of the 8.2-m VLT Unit Telescopes (ANTU and MELIPAL), were made one year ago ( ESO PR 23/01 ), interferometric measurements were also obtained of Proxima Centauri . They formed part of the VLTI commissioning and the data were soon released to the ESO community, cf. the special website. Now, an international team of astronomers from Switzerland, France and ESO/Chile has successfully analysed these observations by means of newly developed, advanced software. For the first time ever, they obtained a highly accurate measurement of the size of such a small star . Three other small stars were also

  1. On small clusters

    International Nuclear Information System (INIS)

    Bernardes, N.

    1984-01-01

    A discussion is presented of zero-point motion effects on the binding energy of a small cluster of identical particles interacting through short range attractive-repulsive forces. The model is appropriate to a discussion of both Van der Waals as well as nuclear forces. (Author) [pt

  2. Small Public Library Management

    Science.gov (United States)

    Pearlmutter, Jane; Nelson, Paul

    2012-01-01

    Anyone at the helm of a small public library knows that every little detail counts. But juggling the responsibilities that are part and parcel of the job is far from easy. Finally, here's a handbook that includes everything administrators need to keep a handle on library operations, freeing them up to streamline and improve how the organization…

  3. Small rover exploration capabilities

    NARCIS (Netherlands)

    Salotti, J.; Laithier, C.; Machut, B.; van Marie, A.; Bruneau, A.; Groemer, G.; Foing, B.H.

    2015-01-01

    For a human mission to the Moon or Mars, an important question is to determine the best strategy for the choice of surface vehicles. Recent studies suggest that the first missions to Mars will be strongly constrained and that only small unpressurized vehicles will be available. We analyze the

  4. Small Open Reading Frames

    Indian Academy of Sciences (India)

    small ORFs and presence of their stable peptide products. Further, examples of biologically active peptides with ... enormous growth in whole genome sequencing. Hence today, genome sequence. Recently, ORFs ... Similarly, during the embryo development of zebrafish, 58 aa long toddler polypeptide produced by a short ...

  5. Small Windmills in Denmark

    DEFF Research Database (Denmark)

    Petersen, H.

    1980-01-01

    The report describes a project for small windmills funded by the Ministry of Energy. The test plant is described and a survey of Danish windmills is presented. Some requirements for windmills are mentioned and regulations governing the interface between grid-connected windmills and the electric u...

  6. Radiotherapy in small countries.

    Science.gov (United States)

    Barton, Michael B; Zubizarreta, Eduardo H; Polo Rubio, J Alfredo

    2017-10-01

    To examine the availability of radiotherapy in small countries. A small country was defined as a country with a population less than one million persons. The economic status of each country was defined using the World Bank Classification. The number of cancers in each country was obtained from GLOBOCAN 2012. The number of cancer cases with an indication or radiotherapy was calculated using the CCORE model. There were 41 countries with a population of under 1 million; 15 were classified as High Income, 15 Upper Middle Income, 10 Lower Middle Income and one Low Income. 28 countries were islands. Populations ranged from 799 (Holy See) to 886450 (Fiji) and the total number of cancer cases occurring in small countries was 21,043 (range by country from 4 to 2476). Overall the total number of radiotherapy cases in small countries was 10982 (range by country from 2 to 1239). Radiotherapy was available in all HIC islands with 80 or more new cases of cancer in 2012 but was not available in any LMIC island. Fiji was the only LMIC island with a large radiotherapy caseload. Similar caseloads in non-island LMIC all had radiotherapy services. Most non-island HIC did not have radiotherapy services presumably because of the easy access to radiotherapy in neighbouring countries. There are no radiotherapy services in any LMIC islands. Copyright © 2017. Published by Elsevier Ltd.

  7. Small bowel resection

    Science.gov (United States)

    ... Ileostomy and your diet Ileostomy - caring for your stoma Ileostomy - changing your pouch Ileostomy - discharge Ileostomy - what to ask your doctor Low-fiber diet Preventing falls Small bowel resection - discharge Surgical wound care - open Types of ileostomy Ulcerative colitis - discharge When ...

  8. Research using small tokamaks

    International Nuclear Information System (INIS)

    1993-01-01

    This document consists of a collection of papers presented at the IAEA Technical Committee Meeting on Research Using Small Tokamaks. It contains 22 papers on a wide variety of research aspects, including diagnostics, design, transport, equilibrium, stability, and confinement. Some of these papers are devoted to other concepts (stellarators, compact tori). Refs, figs and tabs

  9. Small Business Innovations

    Science.gov (United States)

    1993-01-01

    Under an Army Small Business Innovation Research (SBIR) grant, Symbiotics, Inc. developed a software system that permits users to upgrade products from standalone applications so they can communicate in a distributed computing environment. Under a subsequent NASA SBIR grant, Symbiotics added additional tools to the SOCIAL product to enable NASA to coordinate conventional systems for planning Shuttle launch support operations. Using SOCIAL, data may be shared among applications in a computer network even when the applications are written in different programming languages. The product was introduced to the commercial market in 1993 and is used to monitor and control equipment for operation support and to integrate financial networks. The SBIR program was established to increase small business participation in federal R&D activities and to transfer government research to industry. InQuisiX is a reuse library providing high performance classification, cataloging, searching, browsing, retrieval and synthesis capabilities. These form the foundation for software reuse, producing higher quality software at lower cost and in less time. Software Productivity Solutions, Inc. developed the technology under Small Business Innovation Research (SBIR) projects funded by NASA and the Army and is marketing InQuisiX in conjunction with Science Applications International Corporation (SAIC). The SBIR program was established to increase small business participation in federal R&D activities and to transfer government research to industry.

  10. Small angle neutron scattering

    International Nuclear Information System (INIS)

    Gupta, Sanjay

    1982-01-01

    The technique of small angle neutron scattering was first used in Germany less than two decades ago. Since then it has developed very rapidly, and today it is regarded as one of the most powerful techniques in materials, chemical and biological research. During the last decade the combination of high flux reactors and sophisticated instrumentation has revolutionized the technique. This paper endeavours to present a brief but comprehensive review of small angle scattering of neutrons and its applications in solid state research. The domain in which small angle neutron scattering is particularly useful is delineated and some of the methods used in the analysis of data are discussed with special emphasis on recent developments. Typical small angle neutron scattering cameras are described. Finally some experimental results on heterogeneities in metallic systems (both static and dynamic studies), radiation damage in materials, superconductivity, magnetic materials and the technologically very important area of non-destructive testing are reviewed in order to illustrate the wide range of applicability of this technique to problems in solid state research. (author)

  11. Small hydroelectric power plants

    International Nuclear Information System (INIS)

    Helgesen, Boerre

    2002-01-01

    Small hydroelectric power plants are power plants of 1 - 10 MW. For a supplier, this is an unnatural limit. A more natural limit involves compact engine design and simplified control system. The article discusses most of the engine and electrotechnical aspects in the development, construction and operation of such a plant

  12. Deburring small intersecting holes

    Energy Technology Data Exchange (ETDEWEB)

    Gillespie, L.K.

    1980-08-01

    Deburring intersecting holes is one of the most difficult deburring tasks faced by many industries. Only 14 of the 37 major deburring processes are applicable to most intersecting hole applications. Only five of these are normally applicable to small or miniature holes. Basic process capabilities and techniques used as a function of hole sizes and intersection depths are summarized.

  13. Imaging the small bowel.

    LENUS (Irish Health Repository)

    Murphy, Kevin P

    2014-03-01

    Radiologic investigations continue to play a pivotal role in the diagnosis of pathologic conditions of the small intestine despite enhancement of capsule endoscopy and double-balloon endoscopy. Imaging techniques continue to evolve and new techniques in MRI in particular, are being developed.

  14. Small hydrogen liquefier

    International Nuclear Information System (INIS)

    Airoldi, V.J.T.; Corat, E.J.; Minucci, M.A.S.; Leite, V.S.F.O.

    1986-09-01

    In this work the deign and construction of a small hydrogen liquefier (two liters per hour maximum production) is described. The isenthalpic expansion process is used, because its construction is simple and it is generally cheaper to operate. A comparison with other liquefier processes, and considerations about their basic theory are also presented. (author) [pt

  15. Small Open Reading Frames

    Indian Academy of Sciences (India)

    are conserved across diverse species, and the functional char- acterization of their peptides reveals their critical role in a broad spectrum of regulatory mechanisms. Further analy- sis of small ORFs is likely throw light on many exciting, un- explored regulatory mechanisms in different developmental stages and tissue types.

  16. A magnetic nanoparticle-clustering biosensor for blu-ray based optical detection of small-molecules

    DEFF Research Database (Denmark)

    Yang, Jaeyoung; Donolato, Marco; Antunes, Paula Soares Martins

    2014-01-01

    -cost instruments limit the advancement of MNP-based assays. We report here a novel MNP-clustering small-molecule assay on an optical readout platform to overcome the limitations aforementioned with the following improvements. First, a facile MNP-clustering assay applicable to diverse small-molecules was realized......In magnetic nanoparticle (MNP)-clustering assays, a target molecule is bound to multiple receptors tethered onto MNPs, triggering MNP-clustering and leading to changes in the size of clusters. However, sandwich-type clustering requires multiple binding-sites on a target molecule, which is often...... unavailable for small-molecules. Furthermore, measuring magnetic properties as signals is not intrinsically selective regarding MNP-cluster size. Thus, the detection of few MNP-clusters is readily interfered by background signals from predominantly-existing single MNPs. Additionally, bulky and high...

  17. Using machine learning and high-throughput RNA sequencing to classify the precursors of small non-coding RNAs.

    Science.gov (United States)

    Ryvkin, Paul; Leung, Yuk Yee; Ungar, Lyle H; Gregory, Brian D; Wang, Li-San

    2014-05-01

    Recent advances in high-throughput sequencing allow researchers to examine the transcriptome in more detail than ever before. Using a method known as high-throughput small RNA-sequencing, we can now profile the expression of small regulatory RNAs such as microRNAs and small interfering RNAs (siRNAs) with a great deal of sensitivity. However, there are many other types of small RNAs (small nucleolar RNAs), snRNAs (small nuclear RNAs), scRNAs (small cytoplasmic RNAs), tRNAs (transfer RNAs), and transposon-derived RNAs. Here, we present a user's guide for CoRAL (Classification of RNAs by Analysis of Length), a computational method for discriminating between different classes of RNA using high-throughput small RNA-sequencing data. Not only can CoRAL distinguish between RNA classes with high accuracy, but it also uses features that are relevant to small RNA biogenesis pathways. By doing so, CoRAL can give biologists a glimpse into the characteristics of different RNA processing pathways and how these might differ between tissue types, biological conditions, or even different species. CoRAL is available at http://wanglab.pcbi.upenn.edu/coral/. Copyright © 2013 Elsevier Inc. All rights reserved.

  18. Metalloprotease NleC suppresses host NF-κB/inflammatory responses by cleaving p65 and interfering with the p65/RPS3 interaction.

    Directory of Open Access Journals (Sweden)

    Andrea Hodgson

    2015-03-01

    Full Text Available Attaching/Effacing (A/E pathogens including enteropathogenic Escherichia coli (EPEC, enterohemorrhagic E. coli (EHEC and the rodent equivalent Citrobacter rodentium are important causative agents of foodborne diseases. Upon infection, a myriad of virulence proteins (effectors encoded by A/E pathogens are injected through their conserved type III secretion systems (T3SS into host cells where they interfere with cell signaling cascades, in particular the nuclear factor kappaB (NF-κB signaling pathway that orchestrates both innate and adaptive immune responses for host defense. Among the T3SS-secreted non-LEE-encoded (Nle effectors, NleC, a metalloprotease, has been recently elucidated to modulate host NF-κB signaling by cleaving NF-κB Rel subunits. However, it remains elusive how NleC recognizes NF-κB Rel subunits and how the NleC-mediated cleavage impacts on host immune responses in infected cells and animals. In this study, we show that NleC specifically targets p65/RelA through an interaction with a unique N-terminal sequence in p65. NleC cleaves p65 in intestinal epithelial cells, albeit a small percentage of the molecule, to generate the p65¹⁻³⁸ fragment during C. rodentium infection in cultured cells. Moreover, the NleC-mediated p65 cleavage substantially affects the expression of a subset of NF-κB target genes encoding proinflammatory cytokines/chemokines, immune cell infiltration in the colon, and tissue injury in C. rodentium-infected mice. Mechanistically, the NleC cleavage-generated p65¹⁻³⁸ fragment interferes with the interaction between p65 and ribosomal protein S3 (RPS3, a 'specifier' subunit of NF-κB that confers a subset of proinflammatory gene transcription, which amplifies the effect of cleaving only a small percentage of p65 to modulate NF-κB-mediated gene expression. Thus, our results reveal a novel mechanism for A/E pathogens to specifically block NF-κB signaling and inflammatory responses by cleaving a

  19. Small Engine & Accessory Test Area

    Data.gov (United States)

    Federal Laboratory Consortium — The Small Engine and Accessories Test Area (SEATA) facilitates testaircraft starting and auxiliary power systems, small engines and accessories. The SEATA consists...

  20. Small steps for hydro

    International Nuclear Information System (INIS)

    Wicke, Peter

    1998-01-01

    The government in Peru has decided to utilise its gas reserves and restrict hydro to relatively small schemes. A number of reasons for the decision are given. In 1997, the Shell-Mobile-Bechtel-COSAPI consortium was formed and agreements were signed regarding exploiting Gas de Camisea. The country's energy needs to 2010 are being assessed. It is likely that by 2001 the whole of south Peru will be receiving gas from Camisea. The Peru situation is discussed under the headings of (i) existing capacity, (ii) growing demands, (iii) a history of hydro in Peru, (iv) electrification and SHP and (v) outlook. The future for Peru's electric energy development is bright. While most of its new power capacity will come from natural gas, the small hydros also have a part to play. A stronger commitment of national and regional political authorities to consider supplies outside the big cities is said to be needed. (UK)

  1. Small reactor operating mode

    International Nuclear Information System (INIS)

    Snell, V.G.

    1997-01-01

    There is a potential need for small reactors in the future for applications such as district heating, electricity production at remote sites, and desalination. Nuclear power can provide these at low cost and with insignificant pollution. The economies required by the small scale application, and/or the remote location, require a review of the size and location of the operating staff. Current concepts range all the way from reactors which are fully automatic, and need no local attention for days or weeks, to those with reduced local staff. In general the less dependent a reactor is on local human intervention, the greater its dependence on intrinsic safety features such as passive decay heat removal, low-stored energy and limited reactivity speed and depth in the control systems. A case study of the design and licensing of the SLOWPOKE Energy System heating reactor is presented. (author)

  2. Small Business Innovations (Photodetector)

    Science.gov (United States)

    1991-01-01

    Epitaxx, Inc. of Princeton, NJ, developed the Epitaxx Near Infrared Room Temperature Indium-Gallium-Arsenide (InGaAs) Photodetector based on their Goddard Space Flight Center Small Business Innovation Research (SBIR) contract work to develop a linear detector array for satellite imaging applications using InGaAs alloys that didn't need to be cooled to (difficult and expensive) cryogenic temperatures. The photodetectors can be used for remote sensing, fiber optic and laser position-sensing applications.

  3. Small Business Innovations (MISER)

    Science.gov (United States)

    1991-01-01

    Lightwave Electronics Corporation, Mountain View, CA, developed the Series 120 and 122 non-planner diode pumped ring lasers based on a low noise ring laser with voltage tuning that they delivered to Jet Propulsion Laboratory under a Small Business Innovation Research (SBIR) contract. The voltage tuning feature allows "phase-locking" the lasers, making them "electronic," similar to radio and microwave electronic oscillators. The Series 120 and 122 can be applied to fiber sensing, coherent communications and laser radar.

  4. Big Data, Small Sample.

    Science.gov (United States)

    Gerlovina, Inna; van der Laan, Mark J; Hubbard, Alan

    2017-05-20

    Multiple comparisons and small sample size, common characteristics of many types of "Big Data" including those that are produced by genomic studies, present specific challenges that affect reliability of inference. Use of multiple testing procedures necessitates calculation of very small tail probabilities of a test statistic distribution. Results based on large deviation theory provide a formal condition that is necessary to guarantee error rate control given practical sample sizes, linking the number of tests and the sample size; this condition, however, is rarely satisfied. Using methods that are based on Edgeworth expansions (relying especially on the work of Peter Hall), we explore the impact of departures of sampling distributions from typical assumptions on actual error rates. Our investigation illustrates how far the actual error rates can be from the declared nominal levels, suggesting potentially wide-spread problems with error rate control, specifically excessive false positives. This is an important factor that contributes to "reproducibility crisis". We also review some other commonly used methods (such as permutation and methods based on finite sampling inequalities) in their application to multiple testing/small sample data. We point out that Edgeworth expansions, providing higher order approximations to the sampling distribution, offer a promising direction for data analysis that could improve reliability of studies relying on large numbers of comparisons with modest sample sizes.

  5. In Vivo Testing of MicroRNA-Mediated Gene Knockdown in Zebrafish

    Directory of Open Access Journals (Sweden)

    Ivone Un San Leong

    2012-01-01

    Full Text Available The zebrafish (Danio rerio has become an attractive model for human disease modeling as there are a large number of orthologous genes that encode similar proteins to those found in humans. The number of tools available to manipulate the zebrafish genome is limited and many currently used techniques are only effective during early development (such as morpholino-based antisense technology or it is phenotypically driven and does not offer targeted gene knockdown (such as chemical mutagenesis. The use of RNA interference has been met with controversy as off-target effects can make interpreting phenotypic outcomes difficult; however, this has been resolved by creating zebrafish lines that contain stably integrated miRNA constructs that target the desired gene of interest. In this study, we show that a commercially available miRNA vector system with a mouse-derived miRNA backbone is functional in zebrafish and is effective in causing eGFP knockdown in a transient in vivo eGFP sensor assay system. We chose to apply this system to the knockdown of transcripts that are implicated in the human cardiac disorder, Long QT syndrome.

  6. Non-specific dsRNA-mediated antiviral response in the honey bee.

    Directory of Open Access Journals (Sweden)

    Michelle L Flenniken

    Full Text Available Honey bees are essential pollinators of numerous agricultural crops. Since 2006, honey bee populations have suffered considerable annual losses that are partially attributed to Colony Collapse Disorder (CCD. CCD is an unexplained phenomenon that correlates with elevated incidence of pathogens, including RNA viruses. Honey bees are eusocial insects that live in colonies of genetically related individuals that work in concert to gather and store nutrients. Their social organization provides numerous benefits, but also facilitates pathogen transmission between individuals. To investigate honey bee antiviral defense mechanisms, we developed an RNA virus infection model and discovered that administration of dsRNA, regardless of sequence, reduced virus infection. Our results suggest that dsRNA, a viral pathogen associated molecular pattern (PAMP, triggers an antiviral response that controls virus infection in honey bees.

  7. siRNA-mediated knockdown of endogenously expressed bestrophin in smooth muscles

    DEFF Research Database (Denmark)

    Larsen, Per; Matchkov, Vladimir; Nilsson, Holger

     We have recently characterized in smooth muscle cells a unique cGMP-dependent Ca2+-activated Cl- current (ICl(cGMP-Ca)) that co-exists with a "classical" Ca2+-activated Cl- current. We hypothesized that bestrophin-4 (a product of the VMD2-like 3 gene) could be responsible for the ICl(cGMP-Ca) ba...... We have recently characterized in smooth muscle cells a unique cGMP-dependent Ca2+-activated Cl- current (ICl(cGMP-Ca)) that co-exists with a "classical" Ca2+-activated Cl- current. We hypothesized that bestrophin-4 (a product of the VMD2-like 3 gene) could be responsible for the ICl...... was used. Cultured aortic smooth muscle cells (A7r5) were transfected with siRNA directed against bestrophin-4 and cultured for 3 days. The efficiency of transfection was demonstrated by specific perinuclear fluorescence of Cy3-labelled siRNA. The downregulation of targeted protein expression...... is responsible for the ICl(cGMP-Ca) in smooth muscle cells. This study presents a novel efficient technique for specific downregulation of gene expression in blood vessels, much needed in studies of vascular function....

  8. MicroRNA Mediating Networks in Granulosa Cells Associated with Ovarian Follicular Development

    Directory of Open Access Journals (Sweden)

    Baoyun Zhang

    2017-01-01

    Full Text Available Ovaries, which provide a place for follicular development and oocyte maturation, are important organs in female mammals. Follicular development is complicated physiological progress mediated by various regulatory factors including microRNAs (miRNAs. To demonstrate the role of miRNAs in follicular development, this study analyzed the expression patterns of miRNAs in granulosa cells through investigating three previous datasets generated by Illumina miRNA deep sequencing. Furthermore, via bioinformatic analyses, we dissected the associated functional networks of the observed significant miRNAs, in terms of interacting with signal pathways and transcription factors. During the growth and selection of dominant follicles, 15 dysregulated miRNAs and 139 associated pathways were screened out. In comparison of different styles of follicles, 7 commonly abundant miRNAs and 195 pathways, as well as 10 differentially expressed miRNAs and 117 pathways in dominant follicles in comparison with subordinate follicles, were collected. Furthermore, SMAD2 was identified as a hub factor in regulating follicular development. The regulation of miR-26a/b on smad2 messenger RNA has been further testified by real time PCR. In conclusion, we established functional networks which play critical roles in follicular development including pivotal miRNAs, pathways, and transcription factors, which contributed to the further investigation about miRNAs associated with mammalian follicular development.

  9. Changes in Oleic Acid Content of Transgenic Soybeans by Antisense RNA Mediated Posttranscriptional Gene Silencing

    Directory of Open Access Journals (Sweden)

    Ling Zhang

    2014-01-01

    Full Text Available The Delta-12 oleate desaturase gene (FAD2-1, which converts oleic acid into linoleic acid, is the key enzyme determining the fatty acid composition of seed oil. In this study, we inhibited the expression of endogenous Delta-12 oleate desaturase GmFad2-1b gene by using antisense RNA in soybean Williams 82. By employing the soybean cotyledonary-node method, a part of the cDNA of soybean GmFad2-1b 801 bp was cloned for the construction of a pCAMBIA3300 vector under the soybean seed promoter BCSP. Leaf painting, LibertyLink strip, PCR, Southern blot, qRT-PCR, and fatty acid analysis were used to detect the insertion and expression of GmFad2-1b in the transgenic soybean lines. The results indicate that the metabolically engineered plants exhibited a significant increase in oleic acid (up to 51.71% and a reduction in palmitic acid (to <3% in their seed oil content. No structural differences were observed between the fatty acids of the transgenic and the nontransgenic oil extracts.

  10. Current knowledge of microRNA-mediated regulation of drug metabolism in humans.

    Science.gov (United States)

    Nakano, Masataka; Nakajima, Miki

    2018-05-02

    Understanding the factors causing inter- and intra-individual differences in drug metabolism potencies is required for the practice of personalized or precision medicine, as well as for the promotion of efficient drug development. The expression of drug-metabolizing enzymes is controlled by transcriptional regulation by nuclear receptors and transcriptional factors, epigenetic regulation, such as DNA methylation and histone acetylation, and post-translational modification. In addition to such regulation mechanisms, recent studies revealed that microRNAs (miRNAs), endogenous ~22-nucleotide non-coding RNAs that regulate gene expression through the translational repression and degradation of mRNAs, significantly contribute to post-transcriptional regulation of drug-metabolizing enzymes. Areas covered: This review summarizes the current knowledge regarding miRNAs-dependent regulation of drug-metabolizing enzymes and transcriptional factors and its physiological and clinical significance. We also describe recent advances in miRNA-dependent regulation research, showing that the presence of pseudogenes, single-nucleotide polymorphisms, and RNA editing affects miRNA targeting. Expert opinion: It is unwavering fact that miRNAs are critical factors causing inter- and intra-individual differences in the expression of drug-metabolizing enzymes. Consideration of miRNA-dependent regulation would be a helpful tool for optimizing personalized and precision medicine.

  11. MicroRNA-Mediated Dynamic Bidirectional Shift between the Subclasses of Glioblastoma Stem-like Cells

    Directory of Open Access Journals (Sweden)

    Arun K. Rooj

    2017-06-01

    Full Text Available Large-scale transcriptomic profiling of glioblastoma (GBM into subtypes has provided remarkable insight into the pathobiology and heterogeneous nature of this disease. The mechanisms of speciation and inter-subtype transitions of these molecular subtypes require better characterization to facilitate the development of subtype-specific targeting strategies. The deregulation of microRNA expression among GBM subtypes and their subtype-specific targeting mechanisms are poorly understood. To reveal the underlying basis of microRNA-driven complex subpopulation dynamics within the heterogeneous intra-tumoral ecosystem, we characterized the expression of the subtype-enriched microRNA-128 (miR-128 in transcriptionally and phenotypically diverse subpopulations of patient-derived glioblastoma stem-like cells. Because microRNAs are capable of re-arranging the molecular landscape in a cell-type-specific manner, we argue that alterations in miR-128 levels are a potent mechanism of bidirectional transitions between GBM subpopulations, resulting in intermediate hybrid stages and emphasizing highly intricate intra-tumoral networking.

  12. Induction of RNA-mediated resistance to papaya ringspot virus type W

    Czech Academy of Sciences Publication Activity Database

    Krubphachaya, P.; Juříček, Miloslav; Kertbundit, Sunee

    2007-01-01

    Roč. 40, č. 3 (2007), s. 404-411 ISSN 1225-8687 Grant - others:BIOTEC, NSTDA(TH) BT-B-06-PG-14-4503 Institutional research plan: CEZ:AV0Z50380511 Source of funding: V - iné verejné zdroje Keywords : inverted-repeat * in vitro inoculation * PRSV type W Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.141, year: 2007 http://www.jbmb.or.kr/view_article.php3?cont=jbmb&kid=182&mid=13& pid =13

  13. Reduction in Musca domestica fecundity by dsRNA-mediated gene knockdown.

    Directory of Open Access Journals (Sweden)

    Neil D Sanscrainte

    Full Text Available House flies (Musca domestica are worldwide agricultural pests with estimated control costs at $375 million annually in the U.S. Non-target effects and widespread resistance challenge the efficacy of traditional chemical control. Double stranded RNA (dsRNA has been suggested as a biopesticide for M. domestica but a phenotypic response due to the induction of the RNAi pathway has not been demonstrated in adults. In this study female house flies were injected with dsRNA targeting actin-5C or ribosomal protein (RP transcripts RPL26 and RPS6. Ovaries showed highly reduced provisioning and clutch reductions of 94-99% in RP dsRNA treated flies but not in actin-5C or GFP treated flies. Gene expression levels were significantly and specifically reduced in dsRNA injected groups but remained unchanged in the control dsGFP treated group. Furthermore, injections with an Aedes aegypti conspecific dsRNA designed against RPS6 did not impact fecundity, demonstrating species specificity of the RNAi response. Analysis of M. domestica tissues following RPS6 dsRNA injection showed significant reduction of transcript levels in the head, thorax, and abdomen but increased expression in ovarian tissues. This study demonstrates that exogenous dsRNA is specifically effective and has potential efficacy as a highly specific biocontrol intervention in adult house flies. Further work is required to develop effective methods for delivery of dsRNA to adult flies.

  14. A Robust and Efficient Numerical Method for RNA-Mediated Viral Dynamics

    Directory of Open Access Journals (Sweden)

    Vladimir Reinharz

    2017-10-01

    Full Text Available The multiscale model of hepatitis C virus (HCV dynamics, which includes intracellular viral RNA (vRNA replication, has been formulated in recent years in order to provide a new conceptual framework for understanding the mechanism of action of a variety of agents for the treatment of HCV. We present a robust and efficient numerical method that belongs to the family of adaptive stepsize methods and is implicit, a Rosenbrock type method that is highly suited to solve this problem. We provide a Graphical User Interface that applies this method and is useful for simulating viral dynamics during treatment with anti-HCV agents that act against HCV on the molecular level.

  15. Neurobasal media facilitates increased specificity of siRNA-mediated knockdown in primary cerebellar cultures

    DEFF Research Database (Denmark)

    Gustafsson, Julie Ry; Katsioudi, Georgia; Issazadeh-Navikas, Shohreh

    2016-01-01

    be effectively grown in Neurobasal™ media. NEW METHOD: We tested the efficiency of siRNA from the Accell range from Dharmacon™ when delivered in Neurobasal™ media in contrast to the recommended Accell Delivery media provided by the manufacturer. RESULTS: We observed a more specific knockdown of target...... in Neurobasal™ media, than in Accell Delivery media when using cerebellar granule neurons. Transfection efficiency and cell viability was comparable between the two media. COMPARISON WITH EXISTING METHODS: Delivery of siRNA in Neurobasal™ media facilitates increased specificity of the knockdown compared...... to delivery in Accell Delivery media. The off-target effect observed in Accell Delivery media was not a secondary biological response to downregulation of target, but rather a mixture of specific and non-specific off-target effects. CONCLUSIONS: Specific knockdown of target can be achieved in primary...

  16. Intragenomic matching reveals a huge potential for miRNA-mediated regulation in plants

    DEFF Research Database (Denmark)

    Lindow, Morten; Jacobsen, Anders; Nygaard, Sanne

    2007-01-01

    microRNAs (miRNAs) are important post-transcriptional regulators, but the extent of this regulation is uncertain, both with regard to the number of miRNA genes and their targets. Using an algorithm based on intragenomic matching of potential miRNAs and their targets coupled with support vector...... machine classification of miRNA precursors, we explore the potential for regulation by miRNAs in three plant genomes: Arabidopsis thaliana, Populus trichocarpa, and Oryza sativa. We find that the intragenomic matching in conjunction with a supervised learning approach contains enough information to allow...

  17. Regulating infidelity: RNA-mediated recruitment of AID to DNA during class switch recombination.

    Science.gov (United States)

    DiMenna, Lauren J; Chaudhuri, Jayanta

    2016-03-01

    The mechanism by which the DNA deaminase activation-induced cytidine deaminase (AID) is specifically recruited to repetitive switch region DNA during class switch recombination is still poorly understood. Work over the past decade has revealed a strong link between transcription and RNA polymerase-associated factors in AID recruitment, yet none of these processes satisfactorily explain how AID specificity is affected. Here, we review a recent finding wherein AID is guided to switch regions not by a protein factor but by an RNA moiety, and especially one associated with a noncoding RNA that has been long thought of as being inert. This work explains the long-standing requirement of splicing of noncoding transcripts during class switching, and has implications in both B cell-mediated immunity as well as the underlying pathological syndromes associated with the recombination reaction. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. RNA-Mediated cis Regulation in Acinetobacter baumannii Modulates Stress-Induced Phenotypic Variation.

    Science.gov (United States)

    Ching, Carly; Gozzi, Kevin; Heinemann, Björn; Chai, Yunrong; Godoy, Veronica G

    2017-06-01

    In the nosocomial opportunistic pathogen Acinetobacter baumannii , RecA-dependent mutagenesis, which causes antibiotic resistance acquisition, is linked to the DNA damage response (DDR). Notably, unlike the Escherichia coli paradigm, recA and DDR gene expression in A. baumannii is bimodal. Namely, there is phenotypic variation upon DNA damage, which may provide a bet-hedging strategy for survival. Thus, understanding recA gene regulation is key to elucidate the yet unknown DDR regulation in A. baumannii Here, we identify a structured 5' untranslated region (UTR) in the recA transcript which serves as a cis -regulatory element. We show that a predicted stem-loop structure in this 5' UTR affects mRNA half-life and underlies bimodal gene expression and thus phenotypic variation in response to ciprofloxacin treatment. We furthermore show that the stem-loop structure of the recA 5' UTR influences intracellular RecA protein levels and, in vivo , impairing the formation of the stem-loop structure of the recA 5' UTR lowers cell survival of UV treatment and decreases rifampin resistance acquisition from DNA damage-induced mutagenesis. We hypothesize that the 5' UTR allows for stable recA transcripts during stress, including antibiotic treatment, enabling cells to maintain suitable RecA levels for survival. This innovative strategy to regulate the DDR in A. baumannii may contribute to its success as a pathogen. IMPORTANCE Acinetobacter baumannii is an opportunistic pathogen quickly gaining antibiotic resistances. Mutagenesis and antibiotic resistance acquisition are linked to the DNA damage response (DDR). However, how the DDR is regulated in A. baumannii remains unknown, since unlike most bacteria, A. baumannii does not follow the regulation of the Escherichia coli paradigm. In this study, we have started to uncover the mechanisms regulating the novel A. baumannii DDR. We have found that a cis -acting 5' UTR regulates recA transcript stability, RecA protein levels, and DNA damage-induced phenotypic variation. Though 5' UTRs are known to provide stability to transcripts in bacteria, this is the first example in which it regulates a bimodal DDR response through recA transcript stabilization, potentially enabling cells to have enough RecA for survival and genetic variability. Copyright © 2017 American Society for Microbiology.

  19. Antisense RNA mediated inhibition of granule - bound starch synthase gene expression in potato

    NARCIS (Netherlands)

    Kuipers, A.

    1994-01-01

    Potato starch and its derivatives are widely used in several fields of application. The manufacturing of most products requires the modification of native starch with respect to, for example, viscosity and physical stability. In addition to the currently used physical, chemical and

  20. Establishment and characterization of Prnp knockdown neuroblastoma cells using dual microRNA-mediated RNA interference

    Science.gov (United States)

    Lau, Agnes; Westaway, David; McKenzie, Debbie; Aiken, Judd; Kim, Yong-Sun

    2011-01-01

    Prion diseases are fatal transmissible neurodegenerative disorders. In the pathogenesis of the disease, the cellular prion protein (PrPC) is required for replication of abnormal prion (PrPSc), which results in accumulation of PrPSc. Although there have been extensive studies using Prnp knockout systems, the normal function of PrPC remains ambiguous. Compared with conventional germline knockout technologies and transient naked siRNA-dependent knockdown systems, newly constructed durable chained-miRNA could provide a cell culture model that is closer to the disease status and easier to achieve with no detrimental sequelae. The selective silencing of a target gene by RNA interference (RNAi) is a powerful approach to investigate the unknown function of genes in vitro and in vivo. To reduce PrPC expression, a novel dual targeting-microRNA (miRdual) was constructed. The miRdual, which targets N- and C-termini of Prnp simultaneously, more effectively suppressed PrPC expression compared with conventional single site targeting. Furthermore, to investigate the cellular change following PrPC depletion, gene expression analysis of PrPC interacting and/or associating genes and several assays including proliferation, viability and apoptosis were performed. The transcripts 670460F02Rik and Plk3, Ppp2r2b and Csnk2a1 increase in abundance and are reported to be involved in cell proliferation and mitochondrial-mediated apoptosis. Dual-targeting RNAi with miRdual against Prnp will be useful for analyzing the physiological function of PrPC in neuronal cell lines and may provide a potential therapeutic intervention for prion diseases in the future. PMID:21494092

  1. Role of human GRP75 in miRNA mediated regulation of dengue virus replication.

    Science.gov (United States)

    Kakumani, Pavan Kumar; Medigeshi, Guruprasad R; Kaur, Inderjeet; Malhotra, Pawan; Mukherjee, Sunil K; Bhatnagar, Raj K

    2016-07-15

    In recent times, RNAi has emerged as an important defence system that regulates replication of pathogens in host cells. Many RNAi related host factors especially the host miRNAs play important roles in all intrinsic cellular functions, including viral infection. We have been working on identification of mammalian host factors involved in Dengue virus infection. In the present study, we identified Glucose Regulated Protein 75kDa (GRP75), as a host factor that is associated with dicer complex, in particular with HADHA (trifunctional enzyme subunit alpha, mitochondrial), an auxiliary component of dicer complex. Knockdown of GRP75 by respective siRNAs in Huh-7 cells resulted in the accumulation of dengue viral genomic RNA suggesting a role of GRP75 in regulating dengue virus replication in human cell lines. To elucidate the mode of action of GRP75, we over expressed the protein in Huh-7 cells and analysed the host miRNAs processing. The results revealed that, GRP75 is involved in processing of host miRNA, hsa-mir-126, that down regulates dengue virus replication. These findings suggest a regulatory role of human miRNA pathway especially GRP75 protein and hsa-mir-126 in dengue virus replication. These results thus provide insights into the role of miRNAs and RNAi machinery in dengue life cycle. Copyright © 2016 Elsevier B.V. All rights reserved.

  2. Quantitative mapping of RNA-mediated nuclear estrogen receptor β interactome in human breast cancer cells

    Science.gov (United States)

    Giurato, Giorgio; Nassa, Giovanni; Salvati, Annamaria; Alexandrova, Elena; Rizzo, Francesca; Nyman, Tuula A.; Weisz, Alessandro; Tarallo, Roberta

    2018-03-01

    The nuclear receptor estrogen receptor 2 (ESR2, ERβ) modulates cancer cell proliferation and tumor growth, exerting an oncosuppressive role in breast cancer (BC). Interaction proteomics by tandem affinity purification coupled to mass spectrometry was previously applied in BC cells to identify proteins acting in concert with ERβ to control key cellular functions, including gene transcription, RNA splicing and post-transcriptional mRNA regulation. These studies revealed an involvement of RNA in ERβ interactome assembly and functions. By applying native protein complex purification followed by nano LC-MS/MS before and after in vitro RNA removal, we generated a large dataset of newly identified nuclear ERβ interactors, including a subset associating with the receptor via RNA bridging. These datasets will be useful to investigate further the role of ERβ, nuclear RNAs and the other proteins identified here in BC and other cell types.

  3. microRNA-mediated R gene regulation: molecular scabbards for double-edged swords.

    Science.gov (United States)

    Deng, Yingtian; Liu, Minglei; Li, Xiaofei; Li, Feng

    2018-02-01

    Plant resistance (R) proteins are immune receptors that recognize pathogen effectors and trigger rapid defense responses, namely effector-triggered immunity. R protein-mediated pathogen resistance is usually race specific. During plant-pathogen coevolution, plant genomes accumulated large numbers of R genes. Even though plant R genes provide important natural resources for breeding disease-resistant crops, their presence in the plant genome comes at a cost. Misregulation of R genes leads to developmental defects, such as stunted growth and reduced fertility. In the past decade, many microRNAs (miRNAs) have been identified to target various R genes in plant genomes. miRNAs reduce R gene levels under normal conditions and allow induction of R gene expression under various stresses. For these reasons, we consider R genes to be double-edged "swords" and miRNAs as molecular "scabbards". In the present review, we summarize the contributions and potential problems of these "swords" and discuss the features and production of the "scabbards", as well as the mechanisms used to pull the "sword" from the "scabbard" when needed.

  4. Long noncoding RNA-mediated intrachromosomal interactions promote imprinting at the Kcnq1 locus

    Science.gov (United States)

    Zhang, He; Zeitz, Michael J.; Wang, Hong; Niu, Beibei; Ge, Shengfang; Li, Wei; Cui, Jiuwei; Wang, Guanjun; Qian, Guanxiang; Higgins, Michael J.

    2014-01-01

    Kcnq1ot1 is a long noncoding ribonucleic acid (RNA; lncRNA) that participates in the regulation of genes within the Kcnq1 imprinting domain. Using a novel RNA-guided chromatin conformation capture method, we demonstrate that the 5′ region of Kcnq1ot1 RNA orchestrates a long-range intrachromosomal loop between KvDMR1 and the Kcnq1 promoter that is required for maintenance of imprinting. PRC2 (polycomb repressive complex 2), which participates in the allelic repression of Kcnq1, is also recruited by Kcnq1ot1 RNA via EZH2. Targeted suppression of Kcnq1ot1 lncRNA prevents the creation of this long-range intrachromosomal loop and causes loss of Kcnq1 imprinting. These observations delineate a novel mechanism by which an lncRNA directly builds an intrachromosomal interaction complex to establish allele-specific transcriptional gene silencing over a large chromosomal domain. PMID:24395636

  5. Inhibition of Ovarian Cancer by microRNA-mediated Regulation of Telomerase

    Science.gov (United States)

    2009-05-01

    progression, ovarian cancer 16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF ABSTRACT 18. NUMBER OF PAGES 19a. NAME OF RESPONSIBLE PERSON USAMRMC a...studies charac- terizing the 13q14 deletion in human chronic lymphocytic leukemia , which revealed two miRNAs, miR-15a and miR-16-1 (3). Subsequently...Roche) for 1 h and incubated with anti-DIG-AP Fab fragments (Roche) for 12 h. Following wash for three times in 1 maleic acid and 0.3% Tween 20 buffer

  6. A Systems’ Biology Approach to Study MicroRNA-Mediated Gene Regulatory Networks

    Directory of Open Access Journals (Sweden)

    Xin Lai

    2013-01-01

    Full Text Available MicroRNAs (miRNAs are potent effectors in gene regulatory networks where aberrant miRNA expression can contribute to human diseases such as cancer. For a better understanding of the regulatory role of miRNAs in coordinating gene expression, we here present a systems biology approach combining data-driven modeling and model-driven experiments. Such an approach is characterized by an iterative process, including biological data acquisition and integration, network construction, mathematical modeling and experimental validation. To demonstrate the application of this approach, we adopt it to investigate mechanisms of collective repression on p21 by multiple miRNAs. We first construct a p21 regulatory network based on data from the literature and further expand it using algorithms that predict molecular interactions. Based on the network structure, a detailed mechanistic model is established and its parameter values are determined using data. Finally, the calibrated model is used to study the effect of different miRNA expression profiles and cooperative target regulation on p21 expression levels in different biological contexts.

  7. Non-Specific dsRNA-Mediated Antiviral Response in the Honey Bee

    Science.gov (United States)

    Flenniken, Michelle L.; Andino, Raul

    2013-01-01

    Honey bees are essential pollinators of numerous agricultural crops. Since 2006, honey bee populations have suffered considerable annual losses that are partially attributed to Colony Collapse Disorder (CCD). CCD is an unexplained phenomenon that correlates with elevated incidence of pathogens, including RNA viruses. Honey bees are eusocial insects that live in colonies of genetically related individuals that work in concert to gather and store nutrients. Their social organization provides numerous benefits, but also facilitates pathogen transmission between individuals. To investigate honey bee antiviral defense mechanisms, we developed an RNA virus infection model and discovered that administration of dsRNA, regardless of sequence, reduced virus infection. Our results suggest that dsRNA, a viral pathogen associated molecular pattern (PAMP), triggers an antiviral response that controls virus infection in honey bees. PMID:24130869

  8. RNA-mediated gene silencing of superoxide dismutase (bcsod1) in Botrytis cinerea

    NARCIS (Netherlands)

    Patel, R.M.; Kan, van J.A.L.; Bailey, A.M.; Foster, G.D.

    2008-01-01

    Gene silencing is a powerful tool utilized for identification of gene function and analysis in plants, animals, and fungi. Here, we report the silencing of superoxide dismutase (bcsod1) in Botrytis cinerea through sense and antisense-mediated silencing mechanisms. Because superoxide dismutase (SOD)

  9. Tiroiditis autoinmune inducida por interferón en pacientes con infección por virus de la hepatitis C. Interferon-induced autoimmune thyroiditis in a patient with hepatitis C virus infection

    Directory of Open Access Journals (Sweden)

    José L. Pinto

    2011-06-01

    Full Text Available Se reporta el caso de un varón de 43 años de edad, sin antecedentes patológicos de importancia, que acudió por elevación asintomática de la alanino aminotransferasa (ALT. El paciente negó ser bebedor crónico de alcohol. Se hizo el diagnóstico serológico de infección activa por hepatitis C y la biopsia de hígado reveló inflamación crónica activa. Con estos resultados, se inició tratamiento con interferón-alfa y ribavirina. Durante el tratamiento de 48 semanas, el paciente presentó anticuerpos antitiroideos positivos con variaciones en sus niveles de tirotropina (TSH y hormonas tiroideas. En el seguimiento postratamiento, el paciente continuó con hipertiroidismo por enfermedad de Graves. La tiroiditis autoinmune es una complicación frecuente del uso de interferón en pacientes con hepatitis C. En algunos casos se presenta como hipertiroidismo por enfermedad de Graves. Se debe evaluar la función tiroidea y los anticuerpos antitiroideos antes y durante el tratamiento con interferón.A 43 year old man presented with asymptomatic elevation of alanine aminotransferase (ALT and no relevant past history. The patient denied being a chronic alcohol drinker. Work-up revealed an active hepatitis C, and liver biopsy showed active inflammation. Treatment was started with interferon-alfa and ribavirin. During the 48 weeks of treatment, the patient developed positive thyroid antibodies with varying level of thyrotropin (TSH and thyroid hormones. At follow-up after treatment, the patient continued with hyperthyroidism due to Graves’ disease. Autoimmune thyroiditis is a common complication of using interferon in patients with hepatitis C. In some cases, it is presented as hyperthyroidism because of Graves’ disease. Thyroid function and thyroid antibodies should be evaluated before and during treatment with interferon.

  10. Structural insights into mechanisms of the small RNA methyltransferase HEN1

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Ying; Ji, Lijuan; Huang, Qichen; Vassylyev, Dmitry G.; Chen, Xuemei; Ma, Jin-Biao; (UAB); (UCR)

    2010-02-22

    RNA silencing is a conserved regulatory mechanism in fungi, plants and animals that regulates gene expression and defence against viruses and transgenes. Small silencing RNAs of {approx}20-30 nucleotides and their associated effector proteins, the Argonaute family proteins, are the central components in RNA silencing. A subset of small RNAs, such as microRNAs and small interfering RNAs (siRNAs) in plants, Piwi-interacting RNAs in animals and siRNAs in Drosophila, requires an additional crucial step for their maturation; that is, 2'-O-methylation on the 3' terminal nucleotide. A conserved S-adenosyl-L-methionine-dependent RNA methyltransferase, HUA ENHANCER 1 (HEN1), and its homologues are responsible for this specific modification. Here we report the 3.1 {angstrom} crystal structure of full-length HEN1 from Arabidopsis in complex with a 22-nucleotide small RNA duplex and cofactor product S-adenosyl-L-homocysteine. Highly cooperative recognition of the small RNA substrate by multiple RNA binding domains and the methyltransferase domain in HEN1 measures the length of the RNA duplex and determines the substrate specificity. Metal ion coordination by both 2' and 3' hydroxyls on the 3'-terminal nucleotide and four invariant residues in the active site of the methyltransferase domain suggests a novel Mg{sup 2+}-dependent 2'-O-methylation mechanism.

  11. A small RNA activates CFA synthase by isoform-specific mRNA stabilization.

    Science.gov (United States)

    Fröhlich, Kathrin Sophie; Papenfort, Kai; Fekete, Agnes; Vogel, Jörg

    2013-11-13

    Small RNAs use a diversity of well-characterized mechanisms to repress mRNAs, but how they activate gene expression at the mRNA level remains not well understood. The predominant activation mechanism of Hfq-associated small RNAs has been translational control whereby base pairing with the target prevents the formation of an intrinsic inhibitory structure in the mRNA and promotes translation initiation. Here, we report a translation-independent mechanism whereby the small RNA RydC selectively activates the longer of two isoforms of cfa mRNA (encoding cyclopropane fatty acid synthase) in Salmonella enterica. Target activation is achieved through seed pairing of the pseudoknot-exposed, conserved 5' end of RydC to an upstream region of the cfa mRNA. The seed pairing stabilizes the messenger, likely by interfering directly with RNase E-mediated decay in the 5' untranslated region. Intriguingly, this mechanism is generic such that the activation is equally achieved by seed pairing of unrelated small RNAs, suggesting that this mechanism may be utilized in the design of RNA-controlled synthetic circuits. Physiologically, RydC is the first small RNA known to regulate membrane stability.

  12. Ecology in Small Aquatic Ecosystems

    DEFF Research Database (Denmark)

    Andersen, Mikkel René

    Small ecosystems are many-fold more abundant than their larger counterparts. Both on regional and global scale small lakes outnumber medium and large lakes and account for a much larger surface area. Small streams are also far more common than rivers. Despite their abundance small ecosystems are ...

  13. The small library manager's handbook

    CERN Document Server

    Graves, Alice

    2014-01-01

    The Small Library Manager's Handbook is for librarians working in all types of small libraries. It covers the everyday nuts-and-bolts operations that all librarians must perform. This handbook, written by experts who are small librarians themselves, will help all small librarians to do multiple jobs at the same time.

  14. Small-Molecule Inhibitors of the SOX18 Transcription Factor.

    Science.gov (United States)

    Fontaine, Frank; Overman, Jeroen; Moustaqil, Mehdi; Mamidyala, Sreeman; Salim, Angela; Narasimhan, Kamesh; Prokoph, Nina; Robertson, Avril A B; Lua, Linda; Alexandrov, Kirill; Koopman, Peter; Capon, Robert J; Sierecki, Emma; Gambin, Yann; Jauch, Ralf; Cooper, Matthew A; Zuegg, Johannes; Francois, Mathias

    2017-03-16

    Pharmacological modulation of transcription factors (TFs) has only met little success over the past four decades. This is mostly due to standard drug discovery approaches centered on blocking protein/DNA binding or interfering with post-translational modifications. Recent advances in the field of TF biology have revealed a central role of protein-protein interaction in their mode of action. In an attempt to modulate the activity of SOX18 TF, a known regulator of vascular growth in development and disease, we screened a marine extract library for potential small-molecule inhibitors. We identified two compounds, which inspired a series of synthetic SOX18 inhibitors, able to interfere with the SOX18 HMG DNA-binding domain, and to disrupt HMG-dependent protein-protein interaction with RBPJ. These compounds also perturbed SOX18 transcriptional activity in a cell-based reporter gene system. This approach may prove useful in developing a new class of anti-angiogenic compounds based on the inhibition of TF activity. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. The Small Mars System

    Science.gov (United States)

    Fantino, E.; Grassi, M.; Pasolini, P.; Causa, F.; Molfese, C.; Aurigemma, R.; Cimminiello, N.; de la Torre, D.; Dell'Aversana, P.; Esposito, F.; Gramiccia, L.; Paudice, F.; Punzo, F.; Roma, I.; Savino, R.; Zuppardi, G.

    2017-08-01

    The Small Mars System is a proposed mission to Mars. Funded by the European Space Agency, the project has successfully completed Phase 0. The contractor is ALI S.c.a.r.l., and the study team includes the University of Naples ;Federico II;, the Astronomical Observatory of Capodimonte and the Space Studies Institute of Catalonia. The objectives of the mission are both technological and scientific, and will be achieved by delivering a small Mars lander carrying a dust particle analyser and an aerial drone. The former shall perform in situ measurements of the size distribution and abundance of dust particles suspended in the Martian atmosphere, whereas the latter shall demonstrate low-altitude flight in the rarefied planetary environment. The mission-enabling technology is an innovative umbrella-like heat shield, known as IRENE, developed and patented by ALI. The mission is also a technological demonstration of the shield in the upper atmosphere of Mars. The core characteristics of SMS are the low cost (120 M€) and the small size (320 kg of wet mass at launch, 110 kg at landing), features which stand out with respect to previous Mars landers. To comply with them is extremely challenging at all levels, and sets strict requirements on the choice of the materials, the sizing of payloads and subsystems, their arrangement inside the spacecraft and the launcher's selection. In this contribution, the mission and system concept and design are illustrated and discussed. Special emphasis is given to the innovative features and to the challenges faced in the development of the work.

  16. Small Business Innovations (Cryostat)

    Science.gov (United States)

    1991-01-01

    General Pneumatics Corporation, Scottsdale, AZ, developed an anti- clogging cryostat that liquifies gases by expansion for high pressure through a nozzle to produce cryorefrigeration based on their Kennedy Space Center Small Business Innovation Research (SBIR) work to develop a Joule-Thomson (JT) expansion valve that is less susceptible to clogging by particles or condensed contaminants in the flow than a non-contaminating compressor in a closed cycle Linde-Hampson cryocooler used to generate cryogenic cooling for infrared sensors, super conductors, supercooled electronics and cryosurgery.

  17. Small Business Innovations (Helicopters)

    Science.gov (United States)

    1992-01-01

    The amount of engine power required for a helicopter to hover is an important, but difficult, consideration in helicopter design. The EHPIC program model produces converged, freely distorted wake geometries that generate accurate analysis of wake-induced downwash, allowing good predictions of rotor thrust and power requirements. Continuum Dynamics, Inc., the Small Business Innovation Research (SBIR) company that developed EHPIC, also produces RotorCRAFT, a program for analysis of aerodynamic loading of helicopter blades in forward flight. Both helicopter codes have been licensed to commercial manufacturers.

  18. Small radioisotope powered batteries

    International Nuclear Information System (INIS)

    Myatt, J.

    1975-06-01

    Various methods of converting the large amounts of energy stored in radioisotopes are described. These are based on:- (a) the Seebeck effect; (b) thermionic emission of electrons from a hot body; (c) the Stirling Cycle; and (d) radiovoltaic charge separation in 'p-n' junctions. Small generators in the range 0 to 100 W(e) developed using these effects are described and typical applications for each of these systems are given. These include data collection and transmission from remote sites, implantable medical devices, lighthouses, radio beacons, and space power supplies. (author)

  19. Small circuits for cryptography.

    Energy Technology Data Exchange (ETDEWEB)

    Torgerson, Mark Dolan; Draelos, Timothy John; Schroeppel, Richard Crabtree; Miller, Russell D.; Anderson, William Erik

    2005-10-01

    This report examines a number of hardware circuit design issues associated with implementing certain functions in FPGA and ASIC technologies. Here we show circuit designs for AES and SHA-1 that have an extremely small hardware footprint, yet show reasonably good performance characteristics as compared to the state of the art designs found in the literature. Our AES performance numbers are fueled by an optimized composite field S-box design for the Stratix chipset. Our SHA-1 designs use register packing and feedback functionalities of the Stratix LE, which reduce the logic element usage by as much as 72% as compared to other SHA-1 designs.

  20. Período crítico de interferência das plantas daninhas na cultura do milho baseado na fenologia da cultura Critical period of weed interference in corn crop based on crop phenology

    Directory of Open Access Journals (Sweden)

    L.A. Kozlowski

    2002-12-01

    Full Text Available No ano agrícola 2000/2001 foi conduzido, na Fazenda Experimental Gralha Azul/PUCPR, um experimento de campo com o objetivo de determinar o período crítico para prevenção da interferência das plantas daninhas sobre a cultura do milho, determinado com base na fenologia da cultura. O delineamento experimental utilizado foi o de blocos ao acaso em arranjo fatorial 2x7, com quatro repetições. Os 14 tratamentos testados foram resultados da combinação de duas séries de tratamentos: com a cultura em períodos iniciais de crescimento em competição com as plantas daninhas, e com a cultura em períodos iniciais de crescimento sem competição; estes períodos iniciais foram caracterizados por estádios fenológicos da cultura do milho - V2, V4, V6, V8 e V10 - e duas testemunhas. O experimento foi instalado em uma área sob plantio direto, com semeadura realizada de acordo com a tecnologia recomendada para a cultura, com adubações no sulco e em cobertura e tratamentos fitossanitários, para que as plantas de milho se desenvolvessem normalmente. O período crítico de prevenção da interferência ocorreu entre os estádios fenológicos V2 e V7, e a interferência das plantas daninhas reduziu em média 87% o rendimento de grãos da testemunha em competição durante todo o ciclo da cultura em relação à testemunha sem competição com as plantas daninhas, por todo o ciclo. Com relação à comunidade infestante, as dicotiledôneas representaram 22,3% das plantas daninhas, destacando-se as espécies Taraxacum officinale, Senecio brasiliensis, Rumex obtusifolius e Bidens pilosa, e as monocotiledôneas, 77,7% da comunidade infestante, com destaque para Brachiaria plantaginea. O acúmulo de biomassa seca das plantas de milho, a população final e o número de espigas por planta não foram afetados pela interferência das plantas daninhas.A field experiment was carried out to determine the critical period of weed interference in corn, under a no