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Sample records for apical domain control

  1. Apical domain polarization localizes actin-myosin activity to drive ratchet-like apical constriction.

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    Mason, Frank M; Tworoger, Michael; Martin, Adam C

    2013-08-01

    Apical constriction promotes epithelia folding, which changes tissue architecture. During Drosophila gastrulation, mesoderm cells exhibit repeated contractile pulses that are stabilized such that cells apically constrict like a ratchet. The transcription factor Twist is required to stabilize cell shape. However, it is unknown how Twist spatially coordinates downstream signals to prevent cell relaxation. We find that during constriction, Rho-associated kinase (Rok) is polarized to the middle of the apical domain (medioapical cortex), separate from adherens junctions. Rok recruits or stabilizes medioapical myosin II (Myo-II), which contracts dynamic medioapical actin cables. The formin Diaphanous mediates apical actin assembly to suppress medioapical E-cadherin localization and form stable connections between the medioapical contractile network and adherens junctions. Twist is not required for apical Rok recruitment, but instead polarizes Rok medioapically. Therefore, Twist establishes radial cell polarity of Rok/Myo-II and E-cadherin and promotes medioapical actin assembly in mesoderm cells to stabilize cell shape fluctuations.

  2. Genetic interaction of centrosomin and bazooka in apical domain regulation in Drosophila photoreceptor.

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    Geng Chen

    Full Text Available BACKGROUND: Cell polarity genes including Crumbs (Crb and Par complexes are essential for controlling photoreceptor morphogenesis. Among the Crb and Par complexes, Bazooka (Baz, Par-3 homolog acts as a nodal component for other cell polarity proteins. Therefore, finding other genes interacting with Baz will help us to understand the cell polarity genes' role in photoreceptor morphogenesis. METHODOLOGY/PRINCIPAL FINDINGS: Here, we have found a genetic interaction between baz and centrosomin (cnn. Cnn is a core protein for centrosome which is a major microtubule-organizing center. We analyzed the effect of the cnn mutation on developing eyes to determine its role in photoreceptor morphogenesis. We found that Cnn is dispensable for retinal differentiation in eye imaginal discs during the larval stage. However, photoreceptors deficient in Cnn display dramatic morphogenesis defects including the mislocalization of Crumbs (Crb and Bazooka (Baz during mid-stage pupal eye development, suggesting that Cnn is specifically required for photoreceptor morphogenesis during pupal eye development. This role of Cnn in apical domain modulation was further supported by Cnn's gain-of-function phenotype. Cnn overexpression in photoreceptors caused the expansion of the apical Crb membrane domain, Baz and adherens junctions (AJs. CONCLUSIONS/SIGNIFICANCE: These results strongly suggest that the interaction of Baz and Cnn is essential for apical domain and AJ modulation during photoreceptor morphogenesis, but not for the initial photoreceptor differentiation in the Drosophila photoreceptor.

  3. Copper directs ATP7B to the apical domain of hepatic cells via basolateral endosomes.

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    Nyasae, Lydia K; Schell, Michael J; Hubbard, Ann L

    2014-12-01

    Physiologic Cu levels regulate the intracellular location of the Cu ATPase ATP7B. Here, we determined the routes of Cu-directed trafficking of endogenous ATP7B in the polarized hepatic cell line WIF-B and in the liver in vivo. Copper (10 µm) caused ATP7B to exit the trans-Golgi network (TGN) in vesicles, which trafficked via large basolateral endosomes to the apical domain within 1 h. Although perturbants of luminal acidification had little effect on the TGN localization of ATP7B in low Cu, they blocked delivery to the apical membrane in elevated Cu. If the vesicular proton-pump inhibitor bafilomycin-A1 (Baf) was present with Cu, ATP7B still exited the TGN, but accumulated in large endosomes located near the coverslip, in the basolateral region. Baf washout restored ATP7B trafficking to the apical domain. If ATP7B was staged apically in high Cu, Baf addition promoted the accumulation of ATP7B in subapical endosomes, indicating a blockade of apical recycling, with concomitant loss of ATP7B at the apical membrane. The retrograde pathway to the TGN, induced by Cu removal, was far less affected by Baf than the anterograde (Cu-stimulated) case. Overall, loss of acidification-impaired Cu-regulated trafficking of ATP7B at two main sites: (i) sorting and exit from large basolateral endosomes and (ii) recycling via endosomes near the apical membrane. PMID:25243755

  4. Recycling endosomes in apical plasma membrane domain formation and epithelial cell polarity

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    Golachowska, Magdalena R.; Hoekstra, Dick; van IJzendoorn, Sven C. D.

    2010-01-01

    Recycling endosomes have taken central stage in the intracellular sorting and polarized trafficking of apical and basolateral plasma membrane components. Molecular players in the underlying mechanisms are now emerging, including small GTPases, class V myosins and adaptor proteins. In particular, def

  5. Phosphatidylserine-positive particles in the apical domain of sensory hair cells

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    SHI Xiao-rui; Alfred Nuttall

    2006-01-01

    Apical membrane recycling has been proposed to be important for normal hair cell function. The current study reports an in vitro work that demonstrates the presence of phosphatidylserine (PS) and PS-positive vesicles labeled by Annexin V in the apical portion of hair cells. The following characteristics of the PS-positive vesicles were noticed using scanning confocal fluorescence microscopy: (1) variable sizes around 200 nm; (2)variable distribution patterns (either uniformly along individual stereocilia in the hair bundle or irregular) in the stereocilia from cell to cell; (3) variable sizes and numbers at locations along the border of the cuticular plate (CP),with a large number of them located at the vestigal kinocilial location; (4) motility with some of the vesicles during the observation period; (5) increase in PS labeling and the number of PS-positive vesicles after loud sound stimulation; and (6) decreased PS labeling and PS-positive vesicle numbers following treatment with LY-294002, a PI3 -kinase inhibitor. These results suggest that the presence of PS-positive vesicles at the apical area of hair cells may be indicative of vesicle shedding or transportation of a protein or rafts.

  6. Genetic polymorphism in domain I of the apical membrane antigen-1 among Plasmodium knowlesi clinical isolates from Peninsular Malaysia.

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    Fong, Mun Yik; Wong, Shen Siang; Silva, Jeremy Ryan De; Lau, Yee Ling

    2015-12-01

    The simian malaria parasite Plasmodium knowlesi is now recognized as a species that can cause human malaria. The first report of large scale human knowlesi malaria was in 2004 in Malaysia Borneo. Since then, hundreds of human knowlesi malaria cases have been reported in Southeast Asia. The present study investigates the genetic polymorphism of P. knowlesi DI domain of the apical membrane antigen-1 (AMA-1), a protein considered as a promising vaccine candidate for malaria. The DI domain of AMA-1 gene of P. knowlesi clinical isolates from Peninsular Malaysia was amplified by PCR, cloned into Escherichia coli, then sequenced and analysed. Ninety-seven DI domain sequences were obtained. Comparison at the nucleotide level against P. knowlesi strain H as reference sequence showed 21 synonymous and 25 nonsynonymous mutations. Nonetheless, nucleotide sequence analysis revealed low genetic diversity of the DI domain, and it was under purifying (negative) selection. At the amino acid level, 26 different haplotypes were identified and 2 were predominant haplotypes (H1, H2) with high frequencies. Phylogenetic analysis revealed that the 26 haplotypes could be clustered into 2 distinct groups (I and II). Members of the groups were basically derived from haplotypes H1 and H2, respectively.

  7. Sequence diversity and natural selection at domain I of the apical membrane antigen 1 among Indian Plasmodium falciparum populations

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    Kumar Ashwani

    2007-11-01

    Full Text Available Abstract Background The Plasmodium falciparum apical membrane antigen 1 (AMA1 is a leading malaria vaccine candidate antigen. The complete AMA1 protein is comprised of three domains where domain I exhibits high sequence polymorphism and is thus named as the hyper-variable region (HVR. The present study describes the extent of genetic polymorphism and natural selection at domain I of the ama1 gene among Indian P. falciparum isolates. Methods The part of the ama1 gene covering domain I was PCR amplified and sequenced from 157 P. falciparum isolates collected from five different geographical regions of India. Statistical and phylogenetic analyses of the sequences were done using DnaSP ver. 4. 10. 9 and MEGA version 3.0 packages. Results A total of 57 AMA1 haplotypes were observed among 157 isolates sequenced. Forty-six of these 57 haplotypes are being reported here for the first time. The parasites collected from the high malaria transmission areas (Assam, Orissa, and Andaman and Nicobar Islands showed more haplotypes (H and nucleotide diversity π as compared to low malaria transmission areas (Uttar Pradesh and Goa. The comparison of all five Indian P. falciparum subpopulations indicated moderate level of genetic differentiation and limited gene flow (Fixation index ranging from 0.048 to 0.13 between populations. The difference between rates of non-synonymous and synonymous mutations, Tajima's D and McDonald-Kreitman test statistics suggested that the diversity at domain I of the AMA1 antigen is due to positive natural selection. The minimum recombination events were also high indicating the possible role of recombination in generating AMA1 allelic diversity. Conclusion The level of genetic diversity and diversifying selection were higher in Assam, Orissa, and Andaman and Nicobar Islands populations as compared to Uttar Pradesh and Goa. The amounts of gene flow among these populations were moderate. The data reported here will be valuable for the

  8. Regulated Crb accumulation controls apical constriction and invagination in Drosophila tracheal cells.

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    Letizia, Annalisa; Sotillos, Sol; Campuzano, Sonsoles; Llimargas, Marta

    2011-01-15

    Many epithelial tissues undergo extensive remodelling during morphogenesis. How their epithelial features, such as apicobasal polarity or adhesion, are maintained and remodelled and how adhesion and polarity proteins contribute to morphogenesis are two important questions in development. Here, we approach these issues by investigating the role of the apical determinant protein Crumbs (Crb) during the morphogenesis of the embryonic Drosophila tracheal system. Crb accumulates differentially throughout tracheal development and is required for different tracheal events. The earliest requirement for Crb is for tracheal invagination, which is preceded by an enhanced accumulation of Crb in the invagination domain. There, Crb, acting in parallel with the epidermal growth factor receptor (Egfr) pathway, is required for tracheal cell apical constriction and for organising an actomyosin complex, which we propose is mediated by Crb recruitment of moesin (Moe). The ability of a Crb isoform unable to rescue polarity in crb mutants to otherwise rescue their invagination phenotype, and the converse inability of a FERM-binding domain mutant Crb to rescue faulty invagination, support our hypothesis that it is the absence of Crb-dependent Moe enrichment, and not the polarity defect, that mainly underlies the crb invagination phenotype. This hypothesis is supported by the phenotype of lethal giant larvae (lgl); crb double mutants. These results unveil a link between Crb and the organisation of the actin cytoskeleton during morphogenesis. PMID:21172808

  9. Genetic polymorphism and effect of natural selection at domain I of apical membrane antigen-1 (AMA-1) in Plasmodium vivax isolates from Myanmar.

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    Moon, Sung-Ung; Na, Byoung-Kuk; Kang, Jung-Mi; Kim, Jung-Yeon; Cho, Shin-Hyeong; Park, Yun-Kyu; Sohn, Woon-Mok; Lin, Khin; Kim, Tong-Soo

    2010-05-01

    Malaria is endemic or hypoendemic in Myanmar and the country still contributes to the high level of malaria deaths in South-East Asia. Although information on the nature and extent of population diversity within malaria parasites in the country is essential not only for understanding the epidemic situation but also to establish a proper control strategy, very little data is currently available on the extent of genetic polymorphisms of the malaria parasites in Myanmar. In this study, we analyzed the genetic polymorphism and natural selection at domain I of the apical membrane antigen-1 (AMA-1) among Plasmodium vivax Myanmar isolates. A total of 34 distinguishable haplotypes were identified among the 76 isolates sequenced. Comparison with the previously available PvAMA-1 sequences in the GenBank database revealed that 21 of them were new haplotypes that have never been reported till date. The difference between the rate of nonsynonymous (dN) and synonymous (dS) mutations was positive (dN-dS, 0.013+/-0.005), suggesting the domain I is under positive natural selection. The Tajima's D statistics was found to be -0.74652, suggesting that the gene has evolved under population size expansion and/or positive selection. The minimum recombination events were also high, indicating that recombination may occur within the domain I resulting in allelic diversity of PvAMA-1. Our results collectively suggest that PvAMA-1 displays high genetic polymorphism among Myanmar P. vivax isolates with highly diversifying selection at domain I. These results have significant implications in understanding the nature of P. vivax population circulating in Myanmar as well as providing useful information for malaria vaccine development based on this antigen.

  10. Auxin controls local cytokinin biosynthesis in the nodal stem in apical dominance.

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    Tanaka, Mina; Takei, Kentaro; Kojima, Mikiko; Sakakibara, Hitoshi; Mori, Hitoshi

    2006-03-01

    In intact plants, the shoot apex grows predominantly and inhibits outgrowth of axillary buds. After decapitation of the shoot apex, outgrowth of axillary buds begins. This phenomenon is called an apical dominance. Although the involvement of auxin, which represses outgrowth of axillary buds, and cytokinin (CK), which promotes outgrowth of axillary buds, has been proposed, little is known about the underlying molecular mechanisms. In the present study, we demonstrated that auxin negatively regulates local CK biosynthesis in the nodal stem by controlling the expression level of the pea (Pisum sativum L.) gene adenosine phosphate-isopentenyltransferase (PsIPT), which encodes a key enzyme in CK biosynthesis. Before decapitation, PsIPT1 and PsIPT2 transcripts were undetectable; after decapitation, they were markedly induced in the nodal stem along with accumulation of CK. Expression of PsIPT was repressed by the application of indole-3-acetic acid (IAA). In excised nodal stem, PsIPT expression and CK levels also increased under IAA-free conditions. Furthermore, beta-glucuronidase expression, under the control of the PsIPT2 promoter region in transgenic Arabidopsis, was repressed by an IAA. Our results indicate that in apical dominance one role of auxin is to repress local biosynthesis of CK in the nodal stem and that, after decapitation, CKs, which are thought to be derived from the roots, are locally biosynthesized in the nodal stem rather than in the roots. PMID:16507092

  11. Sequence Analysis of Different Domains of Plasmodium Vivax Apical Membrane Antigen (PvAMA-1 Gene Locus in Iran

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    MR Khoramizade

    2012-02-01

    Full Text Available Background: Plasmodium vivax is responsible for approximately 80 million malaria cases in the world. Apical membrane antigen1 (AMA-1 is a type I integral membrane protein present in all Plasmodium species. AMA-1 interferes in critical steps of invasion of human hepatocytes by sporozoites and red blood cells by merozoites and is one of the most immunodominant antigens for eliciting a protective immune response in human. It is considered as a promising antigen for inclusion in a vaccine against P. vivax. Since more knowledge is needed to lighten the scope of such antigen we compared genetic variation in P. vivax AMA-1from an Iranian isolate with those reported from some of the other malarious countries so far.Methods: P. vivax genomic DNA was extracted from the whole blood of an Iranian patient with patent P. vivax infection. The nucleotide sequence for 446 amino acid (AA residues (42-488 of PvAMA-1 was amplified by PCR and cloned in pUC19 vector for sequencing.Results: Sequence analysis of the antigen showed a high degree of identity (99% with strong homology to the PvAMA-1 gene of P. vivax S3 and SKO814 isolates from India and Korea (Asian isolates respectively, and 96% similarity with P. vivax Sal-1 AMA-1 gene from El Salvador.Conclusions: We cloned and characterized three domains of PvAMA-1 gene from an Iranian patient. Predicted protein sequence of this gene showed some discrepancies in corresponding protein in comparing with similar genes reported from other malarious countries.

  12. A polarized cell model for Chikungunya virus infection: entry and egress of virus occurs at the apical domain of polarized cells.

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    Pei Jin Lim

    2014-02-01

    Full Text Available Chikungunya virus (CHIKV has resulted in several outbreaks in the past six decades. The clinical symptoms of Chikungunya infection include fever, skin rash, arthralgia, and an increasing incidence of encephalitis. The re-emergence of CHIKV with more severe pathogenesis highlights its potential threat on our human health. In this study, polarized HBMEC, polarized Vero C1008 and non-polarized Vero cells grown on cell culture inserts were infected with CHIKV apically or basolaterally. Plaque assays, viral binding assays and immunofluorescence assays demonstrated apical entry and release of CHIKV in polarized HBMEC and Vero C1008. Drug treatment studies were performed to elucidate both host cell and viral factors involved in the sorting and release of CHIKV at the apical domain of polarized cells. Disruption of host cell myosin II, microtubule and microfilament networks did not disrupt the polarized release of CHIKV. However, treatment with tunicamycin resulted in a bi-directional release of CHIKV, suggesting that N-glycans of CHIKV envelope glycoproteins could serve as apical sorting signals.

  13. NHERF1/EBP50 Controls Morphogenesis of 3D Colonic Glands by Stabilizing PTEN and Ezrin-Radixin-Moesin Proteins at the Apical Membrane

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    Maria-Magdalena Georgescu

    2014-04-01

    Full Text Available Na+/H+ exchanger 3 regulating factor 1/ezrin-radixin-moesin (ERM–binding phosphoprotein 50 (NHERF1/EBP50, an adaptor molecule that interacts with the ERM–neurofibromatosis type 2 family of cytoskeletal proteins through its ERM-binding region and with phosphatase and tensin homolog (PTEN and β-catenin through its PDZ domains, has been recently implicated in the progression of various human malignancies, including colorectal cancer (CRC. We report here that NHERF1 controls gland morphogenesis, as demonstrated in three-dimensional (3D human intestinal glands developing from a single nonpolarized cell. Starting from the early two-cell developmental stage, NHERF1 concentrates at the cellular interface in a central membrane disc that marks the apical pole delimiting the forming lumen. NHERF1 depletion leads to severe disruption of the apical-basal polarity, with formation of enlarged and distorted cell spheroids devoid of a central lumen. This characteristic and the increased number of mitoses in NHERF1-depleted spheroids, including multipolar ones, mimic high-grade dysplasia lesions observed in CRC progression. NHERF1 ERM-binding or PDZ-domain mutants fail to localize apically and impair gland formation most likely by outcompeting endogenous ligands, with the latter mutant completely aborting gland development. Examination of NHERF1 ligands showed that even if both ezrin and moesin colocalized with NHERF1 at the apical membrane, moesin but not ezrin depletion disrupted morphogenesis similarly to NHERF1. NHERF1 depletion resulted also in membrane displacement of PTEN and nuclear translocation of β-catenin, events contributing to polarity loss and increased proliferation. These findings reveal an essential role of NHERF1 in epithelial morphogenesis and polarity and validate this 3D system for modeling the molecular changes observed in CRC.

  14. Aversive control: A separate domain?

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    Hineline, Philip N

    1984-01-01

    Traditionally, aversive control has been viewed as a separate domain within behavior theory. Sometimes this separateness has been based upon a distinction between reinforcement and punishment, and sometimes upon a distinction between positive and negative reinforcement. The latter is regarded here as the more compelling basis, due to some inherent procedural asymmetries. An approach to the interpretation of negative reinforcement is presented, with indication of types of experiments that supp...

  15. Rac1 controls epithelial tube length through the apical secretion and polarity pathways

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    Kévin Sollier

    2016-01-01

    Full Text Available The morphometric parameters of epithelial tubes are critical to the physiology and homeostasis of most organs. In addition, many human diseases are associated with tube-size defects. Here, we show that Rac1 limits epithelial tube elongation in the developing fly trachea by promoting Rab5-dependent endocytosis of the apical determinant Crumbs. Rac1 is also involved in a positive feedback loop with the septate junction protein Coracle. Thereby, Rac1 precludes paracellular diffusion and contributes to the septate junction-dependent secretion of the chitin-modifying enzymes Vermiform and Serpentine, which restrict epithelial tube length independently of Crumbs. Thus, Rac1 is a critical component of two important pathways controlling epithelial tube morphogenesis.

  16. Aversive control: A separate domain?

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    Hineline, P N

    1984-11-01

    Traditionally, aversive control has been viewed as a separate domain within behavior theory. Sometimes this separateness has been based upon a distinction between reinforcement and punishment, and sometimes upon a distinction between positive and negative reinforcement. The latter is regarded here as the more compelling basis, due to some inherent procedural asymmetries. An approach to the interpretation of negative reinforcement is presented, with indication of types of experiments that support it and that also point to promising directions for further work. However, most of the interpretive issues that arise here are relevant to positively reinforced behavior as well. These include: possible reformulation of the operant/respondent distinction; the place of emotional concepts in behavior analysis; the need for simultaneous, complementary analysis on differing time scales; the understanding of behavioral situations with rewarding or aversive properties that depend as much upon the contingencies that the situations involve as upon the primary rewarding or aversive stimuli that they include. Thus, an adequate understanding of this domain, which has been traditionally viewed as distinct, has implications for all domains of behavior-analytic theory. PMID:16812404

  17. Aversive control: A separate domain?

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    Hineline, P N

    1984-11-01

    Traditionally, aversive control has been viewed as a separate domain within behavior theory. Sometimes this separateness has been based upon a distinction between reinforcement and punishment, and sometimes upon a distinction between positive and negative reinforcement. The latter is regarded here as the more compelling basis, due to some inherent procedural asymmetries. An approach to the interpretation of negative reinforcement is presented, with indication of types of experiments that support it and that also point to promising directions for further work. However, most of the interpretive issues that arise here are relevant to positively reinforced behavior as well. These include: possible reformulation of the operant/respondent distinction; the place of emotional concepts in behavior analysis; the need for simultaneous, complementary analysis on differing time scales; the understanding of behavioral situations with rewarding or aversive properties that depend as much upon the contingencies that the situations involve as upon the primary rewarding or aversive stimuli that they include. Thus, an adequate understanding of this domain, which has been traditionally viewed as distinct, has implications for all domains of behavior-analytic theory.

  18. Fine Mapping of qPAA8, a Gene Controlling Panicle Apical Development in Rice

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    Zhi-Jun Cheng; Bi-Gang Mao; Su-Wei Gao; Ling Zhang; Jiu-Lin Wang; Cai-Lin Lei; Xin Zhang

    2011-01-01

    In rice,one detrimental factor influencing single panicle yield is the frequent occurrence of panicle apical abortion (PAA) under unfavorable climatic conditions.Until now,no detailed genetic information has been available to avoid PAA in rice breeding.Here,we show that the occurrence of PAA is associated with the accumulation of excess hydrogen peroxide.Quantitative trait loci (QTLs) mapping for PAA in an F2 population derived from the cross of L-05261 (PAA line) x IRAT129 (non-PAA variety) identified seven QTLs over a logarithm of the odd (LOD) threshold of 2.5,explaining approximately 50.1% of phenotypic variance for PAA in total.Five of the QTLs with an increased effect from L-05261,were designated as qPAA3-1,qPAA3-2,qPAA4,qPAA5 and qPAA8,and accounted for 6.8%,5.9%,4.2%,13.0% and 12.2%of phenotypic variance,respectively.We found that the PAA in the early heading plants was mainly controlled by qPAA8.Subsequently,using the sub-populations specific for qPAA8 based on markerassisted selection,we further narrowed qPAA8 to a 37.6-kb interval delimited by markers RM22475 and 8-In1 12.These results are beneficial for PAA gene clone.

  19. The Na+/H+ Exchanger NHE6 in the Endosomal Recycling System Is Involved in the Development of Apical Bile Canalicular Surface Domains in HepG2 Cells

    NARCIS (Netherlands)

    Ohgaki, Ryuichi; Matsushita, Masafumi; Kanazawa, Hiroshi; Ogihara, Satoshi; Hoekstra, Dick; van IJzendoorn, Sven C. D.

    2010-01-01

    Polarized epithelial cells develop and maintain distinct apical and basolateral surface domains despite a continuous flux of membranes between these domains. The Na+/H+ exchanger NHE6 localizes to endosomes but its function is unknown. Here, we demonstrate that polarized hepatoma HepG2 cells express

  20. Retromer controls epithelial cell polarity by trafficking the apical determinant Crumbs.

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    Pocha, Shirin Meher; Wassmer, Thomas; Niehage, Christian; Hoflack, Bernard; Knust, Elisabeth

    2011-07-12

    The evolutionarily conserved apical determinant Crumbs (Crb) is essential for maintaining apicobasal polarity and integrity of many epithelial tissues [1]. Crb levels are crucial for cell polarity and homeostasis, yet strikingly little is known about its trafficking or the mechanism of its apical localization. Using a newly established, liposome-based system described here, we determined Crb to be an interaction partner and cargo of the retromer complex. Retromer is essential for the retrograde transport of numerous transmembrane proteins from endosomes to the trans-Golgi network (TGN) and is conserved between plants, fungi, and animals [2]. We show that loss of retromer function results in a substantial reduction of Crb in Drosophila larvae, wing discs, and the follicle epithelium. Moreover, loss of retromer phenocopies loss of crb by preventing apical localization of key polarity molecules, such as atypical protein kinase C (aPKC) and Par6 in the follicular epithelium, an effect that can be rescued by overexpression of Crb. Additionally, loss of retromer results in multilayering of the follicular epithelium, indicating that epithelial integrity is severely compromised. Our data reveal a mechanism for Crb trafficking by retromer that is vital for maintaining Crb levels and localization. We also show a novel function for retromer in maintaining epithelial cell polarity. PMID:21700461

  1. Apical localization of ASIP/PAR-3:EGFP in zebrafish neuroepithelial cells involves the oligomerization domain CR1, the PDZ domains, and the C-terminal portion of the protein.

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    von Trotha, Jakob W; Campos-Ortega, José A; Reugels, Alexander M

    2006-04-01

    Neurulation in zebrafish (Danio rerio) embryos is characterized by oriented cell divisions and the progressive establishment of cellular polarity. Mitoses in the neural plate and neural tube are planar, but in the neural keel/rod stage, the mitotic spindle rotates by 90 degrees, causing cell divisions to occur perpendicular to the plane of the neuroepithelium. The mechanisms and molecules that establish cellular polarity and cause the stereotypic orientation of the mitotic spindle during neurulation are largely unknown. In Caenorhabditis elegans and Drosophila, the PAR/aPKC complex has been shown to be involved in both establishment of cellular polarity and spindle orientation. Here, we show that the conserved N-terminal oligomerization domain (CR1) and the PDZ domains of ASIP/PAR-3:EGFP are involved in its localization to the apical membrane in zebrafish neuroepithelial cells. We further show that the C-terminal part of ASIP/PAR-3 contributes to proper localization and that the apical localization signals in ASIP/PAR-3 prevent the basolateral localization of a Numb:PAR-3 fusion protein. The parallel orientation of the mitotic spindle in the neural tube, however, is only weakly impaired upon overexpression of various ASIP/PAR-3:EGFP constructs.

  2. Emerging Role of the Ubiquitin Proteasome System in the Control of Shoot Apical Meristem Function

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    Elisabetta Di Giacomo; Giovanna Serino; Giovanna Frugis

    2013-01-01

    The shoot apical meristem (SAM) is a population of undifferentiated cells at the tip of the shoot axis that establishes early during plant embryogenesis and gives rise to all shoot organs throughout the plant's life.A plethora of different families of transcription factors (TFs) play a key role in establishing the equilibrium between cell differentiation and stem cell maintenance in the SAM.Fine tuning of these regulatory proteins is crucial for a proper and fast SAM response to environmental and hormonal cues,and for development progression.One effective way to rapidly inactivate TFs involves regulated proteolysis by the ubiquitin/26S proteasome system (UPS).However,a possible role of UPS-dependent protein degradation in the regulation of key SAM TFs has not been thoroughly investigated.Here,we summarize recent evidence supporting a role for the UPS in SAM maintenance and function.We integrate this survey with an in silico analysis of publicly-available microarray databases which identified ubiquitin ligases that are expressed in specific areas within the SAM,suggesting that they may regulate or act downstream of meristem-specific factors.

  3. Control of magnetic domains and domain walls by themal gradients

    OpenAIRE

    Stärk, Martin

    2015-01-01

    The aim of this work is to study heat effects in thin magnetic films to verify the theoretical prediction of domain wall motion towards a heat source. In the theory, a domain wall moves from a cold region towards the hotter part due to energy minimization processes. It is shown that no electron transport is necessary for this effect as it has been observed in insulators. An analytical model describes the effective field that acts on a domain wall as an external applied magnetic field. This is pr...

  4. 根尖感染的特点和控制技术%The technology of apical infection control

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    余擎; 杨扬; 常蓓

    2014-01-01

    根管治疗术是治疗牙髓病、根尖周病的首选方法,其目标是彻底清除根管系统内的感染,并严密充填以防止再感染。由于根管系统解剖复杂性和感染多样化的存在,使得常规化的根管治疗常常难以彻底清除感染,尤其是根尖部(包括根管内根部1/3和根尖外组织)。根尖部的位置隐蔽,根尖分歧、根管侧支等解剖结构多,治疗器械难以达到,感染控制难度大。本文就根尖部感染的特点和难点进行总结,并对根尖内和根尖外的感染控制策略进行简要介绍,包括根尖部的预备方法,根管消毒和严密根管充填的方法等。%Root canal therapy is the most efficient way to treat pulptitis and periapical inflammation, which can clear infections of root canal systems, fill the root canal firmly, and avoid reinfection. However, the variations in root canal morphology and complexity of infection confer difficulty in thoroughly eliminating microorganisms and their by-products in the root canal system, especially in the root apex area (including the top one-third of the root canal and periapical tissue), which is described as the hardest area to clean during endodontic treatment. Infection is difficult to remove entirely because the apex area is hard to approach using dental instruments and because of the existence of special morphological structures, such as apical ramification, intercanal anastomoses, and lateral branch of root canal. This review gives a brief introduction of the characteristics and difficulties of apical infection and knowledge on how to control such infections, including root apex preparation, irrigation and disinfection, and root canal filling.

  5. Kip-related protein 3 is required for control of endoreduplication in the shoot apical meristem and leaves of Arabidopsis.

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    Jun, Sang Eun; Okushima, Yoko; Nam, Jaesung; Umeda, Masaaki; Kim, Gyung-Tae

    2013-01-01

    The cell cycle plays an important role in the development and adaptation of multicellular organisms; specifically, it allows them to optimally adjust their architecture in response to environmental changes. Kip-related proteins (KRPs) are important negative regulators of cyclin-dependent kinases (CDKs), which positively control the cell cycle during plant development. The Arabidopsis genome possesses seven KRP genes with low sequence similarity and distinct expression patterns; however, why Arabidopsis needs seven KRP genes and how these genes function in cell cycle regulation are unknown. Here, we focused on the characterization of KRP3, which was found to have unique functions in the shoot apical meristem (SAM) and leaves. KRP3 protein was localized to the SAM, including the ground meristem and vascular tissues in the ground part of the SAM and cotyledons. In addition, KRP3 protein was stabilized when treated with MG132, an inhibitor of the 26S proteasome, indicating that the protein may be regulated by 26S proteasome-mediated protein degradation. KRP3-overexpressing (KRP3 OE) transgenic plants showed reduced organ size, serrated leaves, and reduced fertility. Interestingly, the KRP3 OE transgenic plants showed a significant reduction in the size of the SAM with alterations in cell arrangement. In addition, compared to the wild type, the KRP3 OE transgenic plants had a higher DNA ploidy level in the SAM and leaves. Taken together, our data suggest that KRP3 plays important regulatory roles in the cell cycle and endoreduplication in the SAM and leaves. PMID:23314608

  6. Domain specific software architectures: Command and control

    Science.gov (United States)

    Braun, Christine; Hatch, William; Ruegsegger, Theodore; Balzer, Bob; Feather, Martin; Goldman, Neil; Wile, Dave

    1992-01-01

    GTE is the Command and Control contractor for the Domain Specific Software Architectures program. The objective of this program is to develop and demonstrate an architecture-driven, component-based capability for the automated generation of command and control (C2) applications. Such a capability will significantly reduce the cost of C2 applications development and will lead to improved system quality and reliability through the use of proven architectures and components. A major focus of GTE's approach is the automated generation of application components in particular subdomains. Our initial work in this area has concentrated in the message handling subdomain; we have defined and prototyped an approach that can automate one of the most software-intensive parts of C2 systems development. This paper provides an overview of the GTE team's DSSA approach and then presents our work on automated support for message processing.

  7. Bilayer thickness mismatch controls domain size in biomimetic membranes

    Science.gov (United States)

    Heberle, Frederick A.; Petruzielo, Robin S.; Pan, Jianjun; Drazba, Paul; Kučerka, Norbert; Standaert, Robert F.; Feigenson, Gerald W.; Katsara, John

    2013-03-01

    In order to promote functionality, cells may alter the spatial organization of membrane lipids and proteins, including separation of liquid phases into distinct domains. In model membranes, domain size and morphology depend strongly on composition and temperature, but the physicochemical mechanisms controlling them are poorly understood. Theoretical work suggests a role for interfacial energy at domain boundaries, which may be driven in part by thickness mismatch between a domain and its surrounding bilayer. However, no direct evidence linking thickness mismatch to domain size in free-standing bilayers has been reported. We describe the use of Small Angle Neutron Scattering (SANS) to detect domains in simplified lipid-only models that mimic the composition of plasma membrane. We find that domain size is controlled by the degree of acyl chain unsaturation of low-melting temperature lipids, and that this size transition is correlated to changes in the thickness mismatch between coexisting liquid phases.

  8. Estimated Frequency Domain Model Uncertainties used in Robust Controller Design

    DEFF Research Database (Denmark)

    Tøffner-Clausen, S.; Andersen, Palle; Stoustrup, Jakob;

    1994-01-01

    This paper deals with the combination of system identification and robust controller design. Recent results on estimation of frequency domain model uncertainty are......This paper deals with the combination of system identification and robust controller design. Recent results on estimation of frequency domain model uncertainty are...

  9. The propagation of self-control: Self-control in one domain simultaneously improves self-control in other domains.

    Science.gov (United States)

    Tuk, Mirjam A; Zhang, Kuangjie; Sweldens, Steven

    2015-06-01

    [Correction Notice: An Erratum for this article was reported in Vol 144(3) of Journal of Experimental Psychology: General (see record 2015-24174-008). The affiliations for co-authors Kuangjie Zhang and Steven Sweldens were incorrect. All versions of this article have been corrected.] A rich tradition in self-control research has documented the negative consequences of exerting self-control in 1 task for self-control performance in subsequent tasks. However, there is a dearth of research examining what happens when people exert self-control in multiple domains simultaneously. The current research aims to fill this gap. We integrate predictions from the most prominent models of self-control with recent neuropsychological insights in the human inhibition system to generate the novel hypothesis that exerting effortful self-control in 1 task can simultaneously improve self-control in completely unrelated domains. An internal meta-analysis on all 18 studies we conducted shows that exerting self-control in 1 domain (i.e., controlling attention, food consumption, emotions, or thoughts) simultaneously improves self-control in a range of other domains, as demonstrated by, for example, reduced unhealthy food consumption, better Stroop task performance, and less impulsive decision making. A subset of 9 studies demonstrates the crucial nature of task timing-when the same tasks are executed sequentially, our results suggest the emergence of an ego depletion effect. We provide conservative estimates of the self-control facilitation (d = |0.22|) as well as the ego depletion effect size (d = |0.17|) free of data selection and publication biases. These results (a) shed new light on self-control theories, (b) confirm recent claims that previous estimates of the ego depletion effect size were inflated due to publication bias, and (c) provide a blueprint for how to handle the power issues and associated file drawer problems commonly encountered in multistudy research projects. PMID

  10. Polarization control at spin-driven ferroelectric domain walls

    Science.gov (United States)

    Leo, Naëmi; Bergman, Anders; Cano, Andres; Poudel, Narayan; Lorenz, Bernd; Fiebig, Manfred; Meier, Dennis

    2015-04-01

    Unusual electronic states arise at ferroelectric domain walls due to the local symmetry reduction, strain gradients and electrostatics. This particularly applies to improper ferroelectrics, where the polarization is induced by a structural or magnetic order parameter. Because of the subordinate nature of the polarization, the rigid mechanical and electrostatic boundary conditions that constrain domain walls in proper ferroics are lifted. Here we show that spin-driven ferroelectricity promotes the emergence of charged domain walls. This provides new degrees of flexibility for controlling domain-wall charges in a deterministic and reversible process. We create and position a domain wall by an electric field in Mn0.95Co0.05WO4. With a magnetic field we then rotate the polarization and convert neutral into charged domain walls, while its magnetic properties peg the wall to its location. Using atomistic Landau-Lifshitz-Gilbert simulations we quantify the polarization changes across the two wall types and highlight their general occurrence.

  11. Generalized predictive control in the delta-domain

    DEFF Research Database (Denmark)

    Lauritsen, Morten Bach; Jensen, Morten Rostgaard; Poulsen, Niels Kjølstad

    1995-01-01

    considered: one having a well-defined limit as the sampling period tends to zero, the other being a close approximation to the conventional discrete-time GPC. Both algorithms are discrete in nature and well-suited for adaptive control. The fact, that δ-domain model are used does not introduce an......This paper describes new approaches to generalized predictive control formulated in the delta (δ) domain. A new δ-domain version of the continuous-time emulator-based predictor is presented. It produces the optimal estimate in the deterministic case whenever the predictor order is chosen greater...

  12. Optical and thermal control of domain structures in ferroelectric crystals

    OpenAIRE

    Brown, Paul Thomas

    1999-01-01

    This thesis presents the results of investigations into the thermal and optical control of ferroelectric domains within lithium tantalate and strontium barium niobate crystals. The aim of the work was to develop techniques for optically pattering domain inverted structures within ferroelectric crystals. Initial studies involving strontium barium niobate revealed an enhanced temperature sensitivity for transient repoling occurring at room temperatures for this material. This has important...

  13. Formation of charged ferroelectric domain walls with controlled periodicity

    Science.gov (United States)

    Bednyakov, Petr S.; Sluka, Tomas; Tagantsev, Alexander K.; Damjanovic, Dragan; Setter, Nava

    2015-10-01

    Charged domain walls in proper ferroelectrics were shown recently to possess metallic-like conductivity. Unlike conventional heterointerfaces, these walls can be displaced inside a dielectric by an electric field, which is of interest for future electronic circuitry. In addition, theory predicts that charged domain walls may influence the electromechanical response of ferroelectrics, with strong enhancement upon increased charged domain wall density. The existence of charged domain walls in proper ferroelectrics is disfavoured by their high formation energy and methods of their preparation in predefined patterns are unknown. Here we develop the theoretical background for the formation of charged domain walls in proper ferroelectrics using energy considerations and outline favourable conditions for their engineering. We experimentally demonstrate, in BaTiO3 single crystals the controlled build-up of high density charged domain wall patterns, down to a spacing of 7 μm with a predominant mixed electronic and ionic screening scenario, hinting to a possible exploitation of charged domain walls in agile electronics and sensing devices.

  14. Minimal Apical Enlargement for Penetration of Irrigants to the Apical Third of Root Canal System: A Scanning Electron Microscope Study

    OpenAIRE

    P. Srikanth; Krishna, Amaravadi Gopi; Srinivas, Siva; Reddy, E Sujayeendranatha; Battu, Someshwar; Aravelli, Swathi

    2015-01-01

    Background: The aim of this study was to determine minimal apical enlargement for irrigant penetration into apical third of root canal system using scanning electron microscope (SEM). Materials and Methods: Distobuccal canals of 40 freshly extracted human maxillary first molar teeth were instrumented using crown-down technique. The teeth were divided into four test groups according to size of their master apical file (MAF) (#20, #25, #30, #35 0.06% taper), and two control groups. After final ...

  15. Quality control of leather by terahertz time-domain spectroscopy.

    Science.gov (United States)

    Hernandez-Serrano, A I; Corzo-Garcia, S C; Garcia-Sanchez, E; Alfaro, M; Castro-Camus, E

    2014-11-20

    We use terahertz time-domain spectroscopy, combined with effective-medium theory, to measure the moisture content and thickness of leather simultaneously. These results demonstrate that this method could become a standard quality control test for the industrial tanning process. PMID:25607861

  16. A Comparative Study of Apical Healing of Open Apices Using MTA and Ca(OH2 Apical Plugs in Cats

    Directory of Open Access Journals (Sweden)

    M. H. Zarrabi

    2005-06-01

    Full Text Available Statement of problem: Endodontic treatment of necrotic teeth with open apices is a challenge. After ruling out surgery as a treatment scheme and introduction of the multivisit apexification which in turn had its disadvantages, apical plug seems to be a suitable substitute treatment plan for such cases. Apical plug makes the treatment through formation of a barrier against the obturating material in a single visit.Purpose: The purpose of this study was to compare histologically the periapical healing using MTA and calcium hydroxide apical plugs after intervals of 4 and 12 weeks in cats.Materials and Methods: In this clinical trial study 64 canines of 16 healthy and mature cats were divided into 3 groups after a periapical lesion formation by over instrumentation in the apical area with files up to no.120. The first group included 24 teeth on which MTA apical plug was applied. The second group included 24 teeth on which Ca (OH 2 apical plug was applied. In both groups the canals were filled with gutta percha and sealer. The third group included 16 control teeth whose canals were left empty after instrumentation and debridement. The access cavities of all teeth were sealed with varnish and amalgam and the vital perfusion of cats was performed in 4 and 12 week intervals. Statistical analysis was established by χ2 and independence test.Results: After 4 weeks, periapical healing in the first group was 90%, in the second group 80% and in the third group, it was only 12.5 %. After 12 weeks, periapical healing occurred in 100% of the MTA group, while it was 57.1% in the second and 40%in the third group .Generally, in the study of histological parameters of healing, no statistical significant difference was observed between the 2 experimental groups,although the MTA group results were much better than the Ca (OH 2 group especially at 12 weeks.Conclusion: The use of MTA apical plug is more effective than Ca (OH 2 in treatment of necrotic teeth with open

  17. Frequency domain stability criteria for fractional-order control systems

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    This paper concerns about the frequency domain stability criteria for fractional-order control systems. On the base of characteristics of the fractional-order equations solutions, we consider the Nyquist stability criterion in a wider sense and obtain a more common means to analyze the stability of fractional-order systems conveniently. Finally, this paper illustrates the generalized stability criteria with an example to show the effect of the parameters variation on the fractional-order control systems.

  18. Delta-Domain Predictive Control and Identification for Control

    DEFF Research Database (Denmark)

    Lauritsen, Morten Bach

    1997-01-01

    The present thesis is concerned with different aspects of modelling, control and identification of linear systems. Traditionally, discrete-time sampled-data systems are represented using shift-operator parametrizations. Such parametrizations are not suitable at fast sampling rates. An alternative...... minimum-variance predictor as a special case and to have a well-defined continuous-time limit. By means of this new prediction method a unified framework for discrete-time and continuous-time predictive control algorithms is developed. This contains a continuous-time like discrete-time predictive...... controller which is insensitive to the choice of sampling period and has a well-defined limit in the continuous-time case. Also more conventional discrete-time predictive control methods may be described within the unified approach. The predictive control algorithms are extended to frequency weighted...

  19. Cell division activity during apical hook development

    NARCIS (Netherlands)

    Raz, V.; Koornneef, M.

    2001-01-01

    Growth during plant development is predominantly governed by the combined activities of cell division and cell elongation. The relative contribution of both activities controls the growth of a tissue. A fast change in growth is exhibited at the apical hypocotyl of etiolated seedlings where cells gro

  20. Bilayer Thickness Mismatch Controls Domain Size in Model Membranes

    Energy Technology Data Exchange (ETDEWEB)

    Heberle, Frederick A [ORNL; Petruzielo, Robin S [ORNL; Pan, Jianjun [ORNL; Drazba, Paul [ORNL; Kucerka, Norbert [Canadian Neutron Beam Centre and Comelius University (Slovakia); Feigenson, Gerald [Cornell University; Katsaras, John [ORNL

    2013-01-01

    The observation of lateral phase separation in lipid bilayers has received considerable attention, especially in connection to lipid raft phenomena in cells. It is widely accepted that rafts play a central role in cellular processes, notably signal transduction. While micrometer-sized domains are observed with some model membrane mixtures, rafts much smaller than 100 nm beyond the reach of optical microscopy are now thought to exist, both in vitro and in vivo. We have used small-angle neutron scattering, a probe free technique, to measure the size of nanoscopic membrane domains in unilamellar vesicles with unprecedented accuracy. These experiments were performed using a four-component model system containing fixed proportions of cholesterol and the saturated phospholipid 1,2-distearoyl-sn-glycero-3-phosphocholine (DSPC), mixed with varying amounts of the unsaturated phospholipids 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC) and 1,2-dioleoylsn- glycero-3-phosphocholine (DOPC). We find that liquid domain size increases with the extent of acyl chain unsaturation (DOPC:POPC ratio). Furthermore, we find a direct correlation between domain size and the mismatch in bilayer thickness of the coexisting liquid-ordered and liquid-disordered phases, suggesting a dominant role for line tension in controlling domain size. While this result is expected from line tension theories, we provide the first experimental verification in free-floating bilayers. Importantly, we also find that changes in bilayer thickness, which accompany changes in the degree of lipid chain unsaturation, are entirely confined to the disordered phase. Together, these results suggest how the size of functional domains in homeothermic cells may be regulated through changes in lipid composition.

  1. Community capacity domains of dengue prevention and control

    Institute of Scientific and Technical Information of China (English)

    Charuai Suwanbamrung; Ratana Somrongthong; Phechnoy Singchagchai; Luechai Srigernyaung

    2009-01-01

    Objective:To explore the meanings and domains for giving communities the capacity to be successful in den-gue prevention and control.Methods:One hundred and twenty participants were purposely selected from 4 sub-districts of 4 provinces in Southern Thailand with a high dengue incidence.Sixty community leaders and sixty non-community leaders participated in this study.In-depth interviews (IDIs),as well as focus group dis-cussions (FGDs)with tape-recorders and note-taking,were used to collect data.All records were transcribed verbatim and analyzed by using the Colaizzi method for content analysis.Results:The findings showed that people view the creation of a sustainable dengue community program as possible only with the support of each community in its entirety:"everyone,every sector,all participating,and with continuing activities."Commu-nity capacity for dengue prevention and control was dependent on ten domains:1)stakeholder participation, 2)community leadership,3)a core-activities group,4)a problem-solving needs assessment,5)dengue in-formation transfer,6)resource mobilization,7)a sense of community for the dengue problem,8)a dengue network partnership,9)critical dengue situation-management,and 10)continuing dengue prevention and con-trol activities.Conclusion:These community capacity domains can be developed into an assessment tool for the community capacity-building process.Community capacity domains require community leaders and non-com-munity leaders to clarify dengue prevention and control assistance required.

  2. Ferroelectric control of magnetic domains in ultra-thin cobalt layers

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Z.; Stolichnov, I.; Setter, N. [Ceramics Laboratory, EPFL-Swiss Federal Institute of Technology, Lausanne 1015 (Switzerland); Bernand-Mantel, A.; Borrel, J.; Pizzini, S.; Ranno, L.; Herrera Diez, L. [University of Grenoble Alpes, Institut Néel, F-38042 Grenoble (France); CNRS, Institut Néel, F-38042 Grenoble (France); Auffret, S.; Gaudin, G.; Boulle, O. [SPINTEC, UMR-8191, CEA/CNRS/UJF/GINP, INAC, F-38054 Grenoble (France)

    2013-11-25

    Non-volatile ferroelectric control of magnetic domains has been demonstrated in ultra-thin cobalt layers at room temperature. The sensitivity of magnetic anisotropy energy to the electronic structure in a few atomic layers adjacent to the interface allows for ferroelectric control of coercivity and magnetic domain dynamics. These effects have been monitored and quantified using magneto-optical Kerr effect. In particular, the regimes, where the ferroelectric domains enhance/inhibit the magnetic domain nucleation or increase/reduce domain wall velocity, have been explored. Thus, non-destructive and reversible ferroelectric domain writing provides a tool to define the magnetic domain paths, create nucleation sites, or control domain movement.

  3. Guideline for Hand Hygiene in Health-Care Settings. Recommendations of the Healthcare Infection Control Practices Advisory Committee and the HIPAC/SHEA/APIC/IDSA Hand Hygiene Task Force.

    Science.gov (United States)

    Boyce, John M; Pittet, Didier

    2002-12-01

    The Guideline for Hand Hygiene in Health-Care Settings provides health-care workers (HCWs) with a review of data regarding handwashing and hand antisepsis in health-care settings. In addition, it provides specific recommendations to promote improved hand-hygiene practices and reduce transmission of pathogenic microorganisms to patients and personnel in health-care settings. This report reviews studies published since the 1985 CDC guideline (Garner JS, Favero MS. CDC guideline for handwashing and hospital environmental control, 1985. Infect Control 1986;7:231-43) and the 1995 APIC guideline (Larson EL, APIC Guidelines Committee. APIC guideline for handwashing and hand antisepsis in health care settings. Am J Infect Control 1995;23:251-69) were issued and provides an in-depth review of hand-hygiene practices of HCWs, levels of adherence of personnel to recommended handwashing practices, and factors adversely affecting adherence. New studies of the in vivo efficacy of alcohol-based hand rubs and the low incidence of dermatitis associated with their use are reviewed. Recent studies demonstrating the value of multidisciplinary hand-hygiene promotion programs and the potential role of alcohol-based hand rubs in improving hand-hygiene practices are summarized. Recommendations concerning related issues (e.g., the use of surgical hand antiseptics, hand lotions or creams, and wearing of artificial fingernails) are also included. PMID:12461507

  4. Time-domain control of ultrahigh-frequency nanomechanical systems.

    Science.gov (United States)

    Liu, N; Giesen, F; Belov, M; Losby, J; Moroz, J; Fraser, A E; McKinnon, G; Clement, T J; Sauer, V; Hiebert, W K; Freeman, M R

    2008-12-01

    Nanoelectromechanical systems could have applications in fields as diverse as ultrasensitive mass detection and mechanical computation, and can also be used to explore fundamental phenomena such as quantized heat conductance and quantum-limited displacement. Most nanomechanical studies to date have been performed in the frequency domain. However, applications in computation and information storage will require transient excitation and high-speed time-domain operation of nanomechanical systems. Here we show a time-resolved optical approach to the transduction of ultrahigh-frequency nanoelectromechanical systems, and demonstrate that coherent control of nanomechanical oscillation is possible through appropriate pulse programming. A series of cantilevers with resonant frequencies ranging from less than 10 MHz to over 1 GHz are characterized using the same pulse parameters. PMID:19057589

  5. Optical network control plane for multi-domain networking

    DEFF Research Database (Denmark)

    Manolova, Anna Vasileva

    trigger BGP protocol re-convergence. By notifying the proper network elements for changes in the network (e.g. failures), the connection blocking can be significantly reduced. Furthermore, novel restoration mechanisms, which provide differentiated failure handling, are proposed and evaluated. It is shown...... that the applied routing protocol and the topology of the multi-domain nework have very strong influence on the efficiency of the applied restoration techniques. Finally, different challenges of the integration of the GMPLS control framework with the novel Optical Burst Switching technology are analyzed. Existing...

  6. Simulating Observer in Supervisory Control- A Domain-based Method

    Directory of Open Access Journals (Sweden)

    Seyed Morteza Babamir

    2012-06-01

    Full Text Available An Observer in the supervisory control observes responses of a discrete system to events of its environment and reports an unsafe/ critical situation if the response is undesired. An undesired response from the system indicates the system response does not adhere to users’ requirements of the system. Therefore, events and conditions of the system environment and user’s requirements of the system are basic elements to observer in determining correctness of the system response. However, the noteworthy matter is that the events, conditions, and requirements should be defined based on data of problem domain because discrete data are primary ingredients of the environment in discrete systems and they are used by system users as a gauge to express their requirements playing a vital role in safety-critical systems, such as medical and avionic ones. A large quantity of methods has already been proposed to model and simulate supervisory control of discrete systems however, a systematic method relying on data of problem domain is missing. Having extracted events, conditions, and user’s requirements from data of problem domain, a Petri-Net automaton is constructed for identifying violation of user’s requirements. The net constitutes the core of the observer and it is used to identify undesired responses of the system. In the third step, run-time simulation of the observer is suggested using multithreading mechanism and Task Parallel Library (TPL technology of Microsoft. Finally, a case study of a discrete concurrent system is proposed, the method applied and simulation results are analyzed based on the system implementation on a multi-core computer.

  7. Transitions in Dynamo Modes Controlled by the Domain Aspect Ratio

    Science.gov (United States)

    Goudard, L.; Dormy, E.

    2007-12-01

    Magnetic fields of internal origin are observed on many planets in the solar system. The Sun itself acts as a dynamo. While these natural objects are very different in their composition, when it comes to dynamo modeling the governing equations are remarkably similar. One of the controlling parameters to distinguish between these objects is the aspect ratio of the convecting domain. Comparing the Sun to the Earth raises the issue of the nature of reversals. A challenging issue is to determine why the geomagnetic field reverses polarity on an irregular basis, whereas the Sun --which is a much larger object, governed by stronger nonlinearities-- reverses its magnetic polarity on a quasi-periodic timescale of 11 yrs. We use a three-dimensional Boussinesq model (the Parody code) to investigate the transition between these two types of behavior. We show that the aspect ratio of the convecting domain controls the nature of the dynamo field. We report a butterfly-like diagram at large aspect ratio, with magnetic activity near 30° of latitudes, which migrates with time toward the equator. We trace the existence of the dynamo wave solution at various aspect ratio and suggest possible consequences for the geomagnetic secular variation.

  8. Research of the Control Domain of Edges in Regression Testing

    Institute of Scientific and Technical Information of China (English)

    GAO Jian-Hua

    2005-01-01

    Regression testing is the process of validating modified software to provide confidence that the changed parts of the software behave as intended and that the unchanged parts have not been adversely affected by the modifications. The goal of regression testing is to reduce the test suit by testing the new characters and the modified parts of a program with the original test suit. Regression testing is a high cost testing method. This paper presents a regression testing selection technique that can reduce the test suit on the basis of Control Flow Graph (CFG). It import the inherit strategy of object-oriented language to ensure an edge's control domain to reduce the test suit size effectively. We implement the idea by coding the edge. An algorithm is also presented at last.

  9. Adaptive Distributed Admission Control in Differentiated Services Domains

    Institute of Scientific and Technical Information of China (English)

    SHAO Hua-gang; CHEN Xiao; WANG Wei-nong

    2007-01-01

    In this paper we propose a scalable admission control scheme for the QoS sensitivity traffic in DiffServ domains. In our scheme, the ingress routers perform admissibility test in a fully distributed and parallel fashion for requests based on our resource per-assigning mechanism.Then, we introduce a novel two phase token passing mechanism to adaptively optimize resource per-assigning among contending edge ronters in proportion to their traffic.In addition, we adopt a measurement based admission decision-making criterion to gain the benefit of high utilization of statistical multiplexing. Our simulation results indicate that even under very high request load it is possible to perform admission control and resource allocation in parallel without suffering in terms of response time, packet loss rate, or utilization.

  10. Effect of cytokinins on shoot apical meristem in Nicotiana tabacum

    Directory of Open Access Journals (Sweden)

    Uzelac Branka

    2012-01-01

    Full Text Available Cytokinins are involved in plant cell proliferation leading to plant growth and morphogenesis. The size, activity and maintenance of the shoot apical meristem (SAM are defined by a balanced rate of mitotic cell divisions and functional cell differentiation that are controlled by cytokinins. In order to investigate the effect of exogenous cytokinin on SAM, morpho-anatomical changes in the shoot apices of tobacco treated with benzyladenine (BA were compared to those of untreated control plants.

  11. Effect of cytokinins on shoot apical meristem in Nicotiana tabacum

    OpenAIRE

    Uzelac Branka; Janošević Dušica; Stojičić Dragana; Budimir Snežana

    2012-01-01

    Cytokinins are involved in plant cell proliferation leading to plant growth and morphogenesis. The size, activity and maintenance of the shoot apical meristem (SAM) are defined by a balanced rate of mitotic cell divisions and functional cell differentiation that are controlled by cytokinins. In order to investigate the effect of exogenous cytokinin on SAM, morpho-anatomical changes in the shoot apices of tobacco treated with benzyladenine (BA) were compared to those of untreated control...

  12. Adolescents' Interpretations of Parental Control: Differentiated by Domain and Types of Control

    Science.gov (United States)

    Kakihara, Fumiko; Tilton-Weaver, Lauree

    2009-01-01

    To determine whether adolescents interpret parental behavioral and psychological control differently, type, level, and domain of control were manipulated across 3 interpretations (adolescents' competence, mattering to parents, and parental intrusiveness). As expected, adolescents (N = 67, M = 14.25 years) generally interpreted high levels of…

  13. Apical localization of PMCA2w/b is enhanced in terminally polarized MDCK cells

    OpenAIRE

    Antalffy, Géza; Caride, Ariel J.; Pászty, Katalin; Hegedus, Luca; Padanyi, Rita; STREHLER, EMANUEL E.; Enyedi, Ágnes

    2011-01-01

    The “w” splice forms of PMCA2 localize to distinct membrane compartments such as the apical membrane of the lactating mammary epithelium, the stereocilia of inner ear hair cells or the post-synaptic density of hippocampal neurons. Previous studies indicated that PMCA2w/b was not fully targeted to the apical domain of MDCK cells but distributed more evenly to the lateral and apical membrane compartments. Overexpression of the apical scaffold protein NHERF2, however, greatly increased the amoun...

  14. PID Controller Design Based on the Time Domain Information of Robust IMC Controller Using Maximum Sensitivity

    Institute of Scientific and Technical Information of China (English)

    JIN Qibing; LIU Qie; WANG Qi; TIAN Yuqi; WANG Yuanfei

    2013-01-01

    The IMC (Internal Model Control) controller based on robust tuning can improve the robustness and dynamic performance of the system.In this paper,the robustness degree of the control system is investigated based on Maximum Sensitivity (Ms) in depth.And the analytical relationship is obtained between the robustness specification and controller parameters,which gives a clear design criterion to robust IMC controller.Moreover,a novel and simple IMC-PID (Proportional-Integral-Derivative) tuning method is proposed by converting the IMC controller to PID form in terms of the time domain rather than the frequency domain adopted in some conventional IMC-based methods.Hence,the presented IMC-PID gives a good performance with a specific robustness degree.The new IMC-PID method is compared with other classical IMC-PID rules,showing the flexibility and feasibility for a wide range of plants.

  15. Centralized Role-Based Access Control for Federated Multi-Domain Environments

    Institute of Scientific and Technical Information of China (English)

    YU Guangcan; LU Zhengding; LI Ruixuan; MUDAR Sarem

    2006-01-01

    The secure interaction among multiple security domains is a major concern. In this paper, we highlight the issues of secure interoperability among multiple security domains operating under the widely accepted Role Based Access Control (RBAC) model. We propose a model called CRBAC that easily establishes a global policy for roles mapping among multiple security domains. Our model is based on an extension of the RBAC model. Also, multiple security domains were composed to one abstract security domain. Also roles in the multiple domains are translated to permissions of roles in the abstract security domain. These permissions keep theirs hierarchies. The roles in the abstract security domain implement roles mapping among the multiple security domains. Then, authorized users of any security domain can transparently access resources in the multiple domains.

  16. Optimal actuator location of minimum norm controls for heat equation with general controlled domain

    Science.gov (United States)

    Guo, Bao-Zhu; Xu, Yashan; Yang, Dong-Hui

    2016-09-01

    In this paper, we study optimal actuator location of the minimum norm controls for a multi-dimensional heat equation with control defined in the space L2 (Ω × (0 , T)). The actuator domain is time-varying in the sense that it is only required to have a prescribed Lebesgue measure for any moment. We select an optimal actuator location so that the optimal control takes its minimal norm over all possible actuator domains. We build a framework of finding the Nash equilibrium so that we can develop a sufficient and necessary condition to characterize the optimal relaxed solutions for both actuator location and corresponding optimal control of the open-loop system. The existence and uniqueness of the optimal classical solutions are therefore concluded. As a result, we synthesize both optimal actuator location and corresponding optimal control into a time-varying feedbacks.

  17. 前列腺尖部活检疼痛机制及预防的临床研究%Anal canal dentate line: the important anatomic maker in prostate apical biopsy pain control

    Institute of Scientific and Technical Information of China (English)

    高小峰; 周铁; 王林辉; 许传亮; 高旭; 孙颖浩

    2008-01-01

    目的 研究前列腺尖部活检疼痛的发生机理及预防方法. 方法 观察尖部活检时穿刺针的进针位置,设计2种方法来降低疼痛程度.设立3个研究组,应用视觉模拟评分(VAS)尺评估应用不同镇痛方法进行前列腺尖部活检时患者的疼痛程度.对照组:10例,直接进行活检.肛管局麻组:10例,插入直肠探头前行肛管局部麻醉,1%利多卡因10 ml从肛门口向肛管方向环绕腹侧半圈局部浸润麻醉肛管,然后再插入直肠超声探头进行活检.针刺痛觉测试组:15例,穿刺针轻轻接触直肠,以患者有无疼痛的自主感觉判断齿状线的位置(齿状线上方无痛觉,下方有痛觉),然后从齿状线的上方进针活检.3组患者均先行尖部活检,VAS评分结束后再行前列腺其他部位的活检.结果观察尖部活检引起患者剧痛时的进针点,发现其位于齿状线以下的肛管.尖部活检3组的疼痛评分分别为:对照组4.46±1.24,肛管局麻组1.84±0.78,针刺痛觉测试组1.98±0.67(P0.05).对照组与肛管局麻组各有1例术后肛周疼痛,针刺痛觉测试组1例术后发热38.4℃. 结论 前列腺尖部穿刺活检引起的疼痛主要由活检针刺穿齿状线以下的肛管皮肤引起.通过针刺痛觉测试从齿状线上方进针能显著减轻疼痛.肛管局部麻醉虽然能减轻活检时的疼痛,但由于麻醉本身即能引起患者明显疼痛,无益于改善患者整个穿刺过程的疼痛体验.%Objective To explore the causes of more frequently happened painful prostate biopsy at the prostatic apex rather than at other areas of the gland and develop maneuvers to avoid this painful apical prostate biopsy. Methods The prostate apical biopsy needle ptmeture sites in the rectum were recorded and accessed. Two maneuvers were developed to avoid the pain. There were 3 groups in this clinical trail. Ten patients in the control group were performed the apical biopsies routinely without any maneuver. Ten

  18. Haemostatic agents in apical surgery. A systematic review

    Science.gov (United States)

    Clé-Ovejero, Adrià

    2016-01-01

    Background Blood presence in apical surgery can prevent the correct vision of the surgical field, change the physical properties of filling materials and reduce their sealing ability. Objetive To describe which are the most effective and safest haemostatic agents to control bleeding in patients undergoing apical surgery. Material and Methods TWe carried out a systematic review, using Medline and Cochrane Library databases, of human clinical studies published in the last 10 years. Results The agents that proved more effective in bleeding control were calcium sulphate (100%) and collagen plus epinephrine (92.9%) followed by ferric sulphate (60%), gauze packing (30%) and collagen (16.7%). When using aluminium chloride (Expasyl®), over 90% of the apical lesions improved, but this agent seemed to increase swelling. Epinephrine with collagen did not significantly raise either blood pressure or heart rate. Conclusions Despite the use of several haemostatic materials in apical surgery, there is little evidence on their effectiveness and safety. The most effective haemostatic agents were calcium sulphate and epinephrine plus collagen. Epinephrine plus collagen did not seem to significantly raise blood pressure or heart rate during surgery. Aluminium chloride did not increase postoperative pain but could slightly increase postoperative swelling. Randomized clinical trials are needed to assess the haemostatic effectiveness and adverse effects of haemostatic materials in apical surgery. Key words:Haemostasis, apical surgery. PMID:27475689

  19. A Domain-Specific Approach to Adolescent Reporting of Parental Control

    Science.gov (United States)

    Arim, Rubab G.; Marshall, Sheila K.; Shapka, Jennifer D.

    2010-01-01

    This study evaluated the psychometric properties of a newly developed adolescent-reported domain-specific measure of parental behavioral control. In addition, this study examined the relationships between domains of perceived behavioral control and adolescent problem behaviors and tested whether psychological control played a mediating role in…

  20. Dt2 is a gain-of-function MADS-Domain factor gene that controls semi-determinacy in soybean

    Science.gov (United States)

    Similar to Arabidopsis, the wild soybean (Glycine soja) and many soybean (Glycine max) cultivars exhibit indeterminate stem growth controlled by a gene Dt1 – the functional counterpart of the Arabidopsis TFL1. Mutations in TFL1 and Dt1 both result in the shoot apical meristem (SAM) switching from ve...

  1. On the overlap between bilingual language control and domain-general executive control.

    Science.gov (United States)

    Branzi, Francesca M; Calabria, Marco; Boscarino, Maria Lucrezia; Costa, Albert

    2016-05-01

    We explored the overlap between bilingual language control (bLC) and domain-general executive control (EC) by focusing on inhibitory control processes. We tested 62 bilinguals in linguistic and non-linguistic switching tasks for two types of costs, such as the n-1 shift cost and the n-2 repetition cost. In order to explore the involvement of inhibitory control in bLC and EC, we assessed the pattern of switch costs in the two tasks and then we correlated them between tasks. Results showed reduced n-2 repetition costs as compared to n-1 shift costs in the linguistic task only, suggesting that small amount of inhibition were deployed when switching between languages. Importantly, neither the n-1 shift costs nor the n-2 repetition costs were correlated between tasks. These results, supported by additional evidence from the ex-Gaussian analysis, suggest that inhibitory control is differently involved in bLC and in EC. PMID:27043252

  2. Apical versus Basal Neurogenesis Directs Cortical Interneuron Subclass Fate

    Directory of Open Access Journals (Sweden)

    Timothy J. Petros

    2015-11-01

    Full Text Available Fate determination in the mammalian telencephalon, with its diversity of neuronal subtypes and relevance to neuropsychiatric disease, remains a critical area of study in neuroscience. Most studies investigating this topic focus on the diversity of neural progenitors within spatial and temporal domains along the lateral ventricles. Often overlooked is whether the location of neurogenesis within a fate-restricted domain is associated with, or instructive for, distinct neuronal fates. Here, we use in vivo fate mapping and the manipulation of neurogenic location to demonstrate that apical versus basal neurogenesis influences the fate determination of major subgroups of cortical interneurons derived from the subcortical telencephalon. Somatostatin-expressing interneurons arise mainly from apical divisions along the ventricular surface, whereas parvalbumin-expressing interneurons originate predominantly from basal divisions in the subventricular zone. As manipulations that shift neurogenic location alter interneuron subclass fate, these results add an additional dimension to the spatial-temporal determinants of neuronal fate determination.

  3. Multi-time-step domain coupling method with energy control

    DEFF Research Database (Denmark)

    Mahjoubi, N.; Krenk, Steen

    2010-01-01

    A multi-time-step integration method is proposed for solving structural dynamics problems on multiple domains. The method generalizes earlier state-space integration algorithms by introducing displacement constraints via Lagrange multipliers, representing the time-integrated constraint forces ove...

  4. Electric-field-controlled suppression of Walker breakdown and chirality switching in magnetic domain wall motion

    Science.gov (United States)

    Chen, Hong-Bo; Li, You-Quan

    2016-07-01

    We theoretically study the dynamics of a magnetic domain wall controlled by an electric field in the presence of the spin flexoelectric interaction. We reveal that this interaction generates an effective spin torque and results in significant changes in the current-driven domain wall motion. In particular, the electric field can stabilize the domain wall motion, leading to strong suppression of the current-induced Walker breakdown and thus allowing a higher maximum wall velocity. We can furthermore use this electric-field control to efficiently switch the chirality of a moving domain wall in the steady regime.

  5. Enhanced electrical properties of ferroelectric thin films with electric field induced domain control

    International Nuclear Information System (INIS)

    (0 0 1) oriented Pb(Zr0.5Ti0.5)O3 (PZT) thin films with high piezoelectric constant were deposited by the electric field-assisted annealing (EFA-A) of alkoxide-derived precursor thin films. So far, selective orientation control of (0 0 1) domain and (1 0 0) domain is very difficult, especially for the chemical solution deposition (CSD). We tried an electric field induced domain control to improve the electrical properties with CSD. An electric field of 10 kV/cm has been applied during an annealing. The high (0 0 1) domain ratio of 75.6% was obtained from the deconvolution of (0 0 2) and (2 0 0) X-ray diffraction peaks. The PZT thin films showed very high piezoelectric constant of 352 pm/V. This shows electric field induced domain control is very effective to enhance the electrical properties of CSD-derived PZT thin films.

  6. Reliable fuzzy control with domain guaranteed cost for fuzzy systems with actuator failures

    Institute of Scientific and Technical Information of China (English)

    JIA Xinchun; ZHENG Nanning

    2004-01-01

    The reliable fuzzy control with guaranteed cost for T-S fuzzy systems with actuator failure is proposed in this paper. The cost function is a quadratic function with failure input. When the initial state of such systems is known, a design method of the reliable fuzzy controller with reliable guaranteed cost is presented, and the formula of the guaranteed cost is established. When the initial state of such systems is unknown but belongs to a known bounded closed domain, a notion of the reliable domain guaranteed cost (RDGC) for such systems is proposed. For two classes of initial state domain, polygon domain and ellipsoid domain, some design methods for reliable fuzzy controllers with the RDGC are provided. The efficiency of our design methods is finally verified by numerical design and simulation on the Rossler chaotic system.

  7. On general ℋ2 control: from frequency to time domain

    Science.gov (United States)

    Stefanovski, Jovan D.

    2010-12-01

    This article presents a general formula for discrete-time ℋ2 control. It works with the regular and singular case of ℋ2 control, i.e. in the case of possibly non-left-invertible matrices G 12 and non-right-invertible matrices G 21, with possible unit circle invariant zeros. In the generic case, it can be simplified and adapted to work with the plant transfer matrix directly, without invoking the matrices of the parameterisation of stabilising controllers. A further result of this article is the presented necessary and sufficient conditions for state-space ℋ2 control, under only stabilisability and detectability assumptions. If the conditions are satisfied, an observer-based ℋ2 controller is constructed. The corresponding numerical algorithm consists of solving two discrete-time algebraic Riccati systems (DARSs) and two eigen-problems.

  8. A domain specific language and methodology for control systems GUI specification, verification and prototyping

    OpenAIRE

    risoldi, matteo; Buchs, Didier

    2007-01-01

    A work-in-progress domain-specific language and methodology for modeling complex control systems GUIs is presented. MDA techniques are applied for language design and verification, simulation and prototyping.

  9. Apical Ca2+-activated potassium channels in mouse parotid acinar cells.

    Science.gov (United States)

    Almassy, Janos; Won, Jong Hak; Begenisich, Ted B; Yule, David I

    2012-02-01

    Ca(2+) activation of Cl and K channels is a key event underlying stimulated fluid secretion from parotid salivary glands. Cl channels are exclusively present on the apical plasma membrane (PM), whereas the localization of K channels has not been established. Mathematical models have suggested that localization of some K channels to the apical PM is optimum for fluid secretion. A combination of whole cell electrophysiology and temporally resolved digital imaging with local manipulation of intracellular [Ca(2+)] was used to investigate if Ca(2+)-activated K channels are present in the apical PM of parotid acinar cells. Initial experiments established Ca(2+)-buffering conditions that produced brief, localized increases in [Ca(2+)] after focal laser photolysis of caged Ca(2+). Conditions were used to isolate K(+) and Cl(-) conductances. Photolysis at the apical PM resulted in a robust increase in K(+) and Cl(-) currents. A localized reduction in [Ca(2+)] at the apical PM after photolysis of Diazo-2, a caged Ca(2+) chelator, resulted in a decrease in both K(+) and Cl(-) currents. The K(+) currents evoked by apical photolysis were partially blocked by both paxilline and TRAM-34, specific blockers of large-conductance "maxi-K" (BK) and intermediate K (IK), respectively, and almost abolished by incubation with both antagonists. Apical TRAM-34-sensitive K(+) currents were also observed in BK-null parotid acini. In contrast, when the [Ca(2+)] was increased at the basal or lateral PM, no increase in either K(+) or Cl(-) currents was evoked. These data provide strong evidence that K and Cl channels are similarly distributed in the apical PM. Furthermore, both IK and BK channels are present in this domain, and the density of these channels appears higher in the apical versus basolateral PM. Collectively, this study provides support for a model in which fluid secretion is optimized after expression of K channels specifically in the apical PM.

  10. Controller design for flexible, distributed parameter mechanical arms via combined state space and frequency domain techniques

    Science.gov (United States)

    Book, W. J.; Majett, M.

    1982-01-01

    The potential benefits of the ability to control more flexible mechanical arms are discussed. A justification is made in terms of speed of movement. A new controller design procedure is then developed to provide this capability. It uses both a frequency domain representation and a state variable representation of the arm model. The frequency domain model is used to update the modal state variable model to insure decoupled states. The technique is applied to a simple example with encouraging results.

  11. Local electrical control of magnetic order and orientation by ferroelastic domain arrangements just above room temperature

    OpenAIRE

    Phillips, L. C.; Cherifi, R. O.; Ivanovskaya, V.; Zobelli, A.; Infante, I.C.; Jacquet, E.; Guiblin, N.; Ünal, A. A.; Kronast, F.; Dkhil, B.; A. Barthélémy; Bibes, M.; S. Valencia

    2014-01-01

    Ferroic materials (ferromagnetic, ferroelectric, ferroelastic) usually divide into domains with different orientations of their order parameter. Coupling between different ferroic systems creates new functionalities, for instance the electrical control of macroscopic magnetic properties including magnetization and coercive field. Here we show that ferroelastic domains can be used to control both magnetic order and magnetization direction at the nanoscale with a voltage. We use element-specifi...

  12. Optimal Control of Thermo--Fluid Phenomena in Variable Domains

    Science.gov (United States)

    Volkov, Oleg; Protas, Bartosz

    2008-11-01

    This presentation concerns our continued research on adjoint--based optimization of viscous incompressible flows (the Navier--Stokes problem) coupled with heat conduction involving change of phase (the Stefan problem), and occurring in domains with variable boundaries. This problem is motivated by optimization of advanced welding techniques used in automotive manufacturing, where the goal is to determine an optimal heat input, so as to obtain a desired shape of the weld pool surface upon solidification. We argue that computation of sensitivities (gradients) in such free--boundary problems requires the use of the shape--differential calculus as a key ingredient. We also show that, with such tools available, the computational solution of the direct and inverse (optimization) problems can in fact be achieved in a similar manner and in a comparable computational time. Our presentation will address certain mathematical and computational aspects of the method. As an illustration we will consider the two--phase Stefan problem with contact point singularities where our approach allows us to obtain a thermodynamically consistent solution.

  13. Parental behavioral control in academic and non-academic domains: a three-year longitudinal study in the Chinese culture.

    Science.gov (United States)

    Shek, Daniel T L; Lee, Tak Yan

    2007-01-01

    For over three consecutive years, 2559 Chinese adolescents (mean age = 12.65 years at Wave 1) responded to instruments assessing their perceived parental behavioral control based on measures of parental knowledge, expectation, monitoring, and discipline. The results show that compared with parental control in the academic domain, parental control in the non-academic domain (peer relations domain) was relatively weaker, using parental knowledge, parental expectation, parental monitoring, and parental discipline as indicators, and a decline in parental behavioral control occurred over time. Although domain (academic domain versus non-academic domain) X time (Time 1, Time 2 versus Time 3) interaction effects were found, the findings mirrored the main effects of domain and time. Parental education and economic sufficiency were linearly related to differences in parental behavioral control in the academic domain and non-academic domain. The present findings suggest that traditional Chinese cultural emphasis on academic excellence still prevails in the contemporary Chinese culture. PMID:18348428

  14. Monodisperse domains by proteolytic control of the coarsening instability

    CERN Document Server

    Derr, Julien

    2011-01-01

    The coarsening instability typically disrupts steady-state cluster-size distributions. We show that degradation coupled to the cluster size, such as arising from biological proteolysis, leads to a novel fixed-point cluster size. Stochastic evaporative and condensative fluxes determine the width of the fixed-point size distribution. At the fixed-point, we show how the peak size and width depend on number, interactions, and proteolytic rate. This proteolytic size-control mechanism is consistent with the phenomenology of pseudo-pilus length control in the general secretion pathway of bacteria.

  15. Apical constriction initiates new bud formation during monopodial branching of the embryonic chicken lung

    Science.gov (United States)

    Kim, Hye Young; Varner, Victor D.; Nelson, Celeste M.

    2013-01-01

    Branching morphogenesis sculpts the airway epithelium of the lung into a tree-like structure to conduct air and promote gas exchange after birth. In the avian lung, a series of buds emerges from the dorsal surface of the primary bronchus via monopodial branching to form the conducting airways; anatomically, these buds are similar to those formed by domain branching in the mammalian lung. Here, we show that monopodial branching is initiated by apical constriction of the airway epithelium, and not by differential cell proliferation, using computational modeling and quantitative imaging of embryonic chicken lung explants. Both filamentous actin and phosphorylated myosin light chain were enriched at the apical surface of the airway epithelium during monopodial branching. Consistently, inhibiting actomyosin contractility prevented apical constriction and blocked branch initiation. Although cell proliferation was enhanced along the dorsal and ventral aspects of the primary bronchus, especially before branch formation, inhibiting proliferation had no effect on the initiation of branches. To test whether the physical forces from apical constriction alone are sufficient to drive the formation of new buds, we constructed a nonlinear, three-dimensional finite element model of the airway epithelium and used it to simulate apical constriction and proliferation in the primary bronchus. Our results suggest that, consistent with the experimental results, apical constriction is sufficient to drive the early stages of monopodial branching whereas cell proliferation is dispensable. We propose that initial folding of the airway epithelium is driven primarily by apical constriction during monopodial branching of the avian lung. PMID:23824575

  16. Apical localisation of crumbs in the boundary cells of the Drosophila hindgut is independent of its canonical interaction partner stardust.

    Science.gov (United States)

    Kumichel, Alexandra; Knust, Elisabeth

    2014-01-01

    The transmembrane protein Crumbs/Crb is a key regulator of apico-basal epithelial cell polarity, both in Drosophila and in vertebrates. In most cases studied so far, the apical localisation of Drosophila Crumbs depends on the interaction of its C-terminal amino acids with the scaffolding protein Stardust. Consequently, embryos lacking either Crumbs or Stardust develop a very similar phenotype, characterised by the loss of epithelial tissue integrity and cell polarity in many epithelia. An exception is the hindgut, which is not affected by the loss of either gene. The hindgut is a single layered epithelial tube composed of two cell populations, the boundary cells and the principal cells. Here we show that Crumbs localisation in the principal cells depends on Stardust, similarly to other embryonic epithelia. In contrast, localisation of Crumbs in the boundary cells does not require Stardust and is independent of its PDZ domain- and FERM-domain binding motifs. In line with this, the considerable upregulation of Crumbs in boundary cells is not followed by a corresponding upregulation of its canonical binding partners. Our data are the first to suggest a mechanism controlling apical Crumbs localisation, which is independent of its conserved FERM- and PDZ-domain binding motifs.

  17. Apical localisation of crumbs in the boundary cells of the Drosophila hindgut is independent of its canonical interaction partner stardust.

    Directory of Open Access Journals (Sweden)

    Alexandra Kumichel

    Full Text Available The transmembrane protein Crumbs/Crb is a key regulator of apico-basal epithelial cell polarity, both in Drosophila and in vertebrates. In most cases studied so far, the apical localisation of Drosophila Crumbs depends on the interaction of its C-terminal amino acids with the scaffolding protein Stardust. Consequently, embryos lacking either Crumbs or Stardust develop a very similar phenotype, characterised by the loss of epithelial tissue integrity and cell polarity in many epithelia. An exception is the hindgut, which is not affected by the loss of either gene. The hindgut is a single layered epithelial tube composed of two cell populations, the boundary cells and the principal cells. Here we show that Crumbs localisation in the principal cells depends on Stardust, similarly to other embryonic epithelia. In contrast, localisation of Crumbs in the boundary cells does not require Stardust and is independent of its PDZ domain- and FERM-domain binding motifs. In line with this, the considerable upregulation of Crumbs in boundary cells is not followed by a corresponding upregulation of its canonical binding partners. Our data are the first to suggest a mechanism controlling apical Crumbs localisation, which is independent of its conserved FERM- and PDZ-domain binding motifs.

  18. Modulated Magnetic Nanowires for Controlling Domain Wall Motion: Toward 3D Magnetic Memories

    KAUST Repository

    Ivanov, Yurii P.

    2016-05-03

    Cylindrical magnetic nanowires are attractive materials for next generation data storage devices owing to the theoretically achievable high domain wall velocity and their efficient fabrication in highly dense arrays. In order to obtain control over domain wall motion, reliable and well-defined pinning sites are required. Here, we show that modulated nanowires consisting of alternating nickel and cobalt sections facilitate efficient domain wall pinning at the interfaces of those sections. By combining electron holography with micromagnetic simulations, the pinning effect can be explained by the interaction of the stray fields generated at the interface and the domain wall. Utilizing a modified differential phase contrast imaging, we visualized the pinned domain wall with a high resolution, revealing its three-dimensional vortex structure with the previously predicted Bloch point at its center. These findings suggest the potential of modulated nanowires for the development of high-density, three-dimensional data storage devices. © 2016 American Chemical Society.

  19. Temporal measures and controls in ultrafast laser domain; Mesures et controles temporels dans le domaine des lasers ultrabrefs

    Energy Technology Data Exchange (ETDEWEB)

    Oksenhendler, Th

    2004-12-15

    This work presents the development of a streak camera 'jitter free' sweep unit synchronized on a femtosecond laser. This application of high voltage photoconductive switches ('High voltage Auston switch') yields subpicosecond resolution for accumulated images on streak camera on a few hundreds micro joule femtosecond laser. Two others applications of these photoconductive switches are studied: - ultrafast optical commutation by a Pockels cell directly driven by a photoconductive switch (rising edge < 100 ps and jitter < 2 ps), - laser pulse energy self-stabilization experimentally proving that driving a Pockels cell by a photoconductive switch can increase the stability of the laser pulse energy from 7 % to 0.7 % rms. Additionally, the application of the acoustic-optical programmable dispersive filter (Dazzler) to the self referenced spectral phase measurement is presented. As these measurements require a linear filter combined with a non linear filter, it is possible to replace the complete linear part (generally a complex optical set-up) by the Dazzler leading to new kind of linear filters and new measurements. Thus base band autocorrelation and time-domain SPIDER (SPIDER by Fourier transform spectroscopy) have been demonstrated experimentally for the first time. (author)

  20. Cdc42 and k-Ras Control Endothelial Tubulogenesis through Apical Membrane and Cytoskeletal Polarization: Novel Stimulatory Roles for GTPase Effectors, the Small GTPases, Rac2 and Rap1b, and Inhibitory Influence of Arhgap31 and Rasa1.

    Directory of Open Access Journals (Sweden)

    Pieter R Norden

    Full Text Available A critical and understudied property of endothelial cells is their ability to form lumens and tube networks. Although considerable information has been obtained concerning these issues, including the role of Cdc42 and Rac1 and their effectors such as Pak2, Pak4, Par6b, and co-regulators such as integrins, MT1-MMP and Par3; many key questions remain that are necessary to elucidate molecular and signaling requirements for this fundamental process. In this work, we identify new small GTPase regulators of EC tubulogenesis including k-Ras, Rac2 and Rap1b that act in conjunction with Cdc42 as well as the key downstream effectors, IQGAP1, MRCKβ, beta-Pix, GIT1, and Rasip1 (which can assemble into multiprotein complexes with key regulators including α2β1 integrin and MT1-MMP. In addition, we identify the negative regulators, Arhgap31 (by inactivating Cdc42 and Rac and Rasa1 (by inactivating k-Ras and the positive regulator, Arhgap29 (by inactivating RhoA which play a major functional role during the EC tubulogenic process. Human EC siRNA suppression or mouse knockout of Rasip1 leads to identical phenotypes where ECs form extensive cord networks, but cannot generate lumens or tubes. Essential roles for these molecules during EC tubulogenesis include; i establishment of asymmetric EC cytoskeletal polarization (subapical distribution of acetylated tubulin and basal membrane distribution of F-actin; and ii directed membrane trafficking of pinocytic vacuoles or other intracellular vesicles along acetylated tubulin tracks to the developing apical membrane surface. Cdc42 co-localizes subapically with acetylated tubulin, while Rac1 and k-Ras strongly label vacuole/ vesicle membranes which accumulate and fuse together in a polarized, perinuclear manner. We observe polarized apical membrane and subapical accumulation of key GTPases and effectors regulating EC lumen formation including Cdc42, Rac1, Rac2, k-Ras, Rap1b, activated c-Raf and Rasip1 to control EC

  1. Par1b induces asymmetric inheritance of plasma membrane domains via LGN-dependent mitotic spindle orientation in proliferating hepatocytes.

    Directory of Open Access Journals (Sweden)

    Christiaan L Slim

    2013-12-01

    Full Text Available The development and maintenance of polarized epithelial tissue requires a tightly controlled orientation of mitotic cell division relative to the apical polarity axis. Hepatocytes display a unique polarized architecture. We demonstrate that mitotic hepatocytes asymmetrically segregate their apical plasma membrane domain to the nascent daughter cells. The non-polarized nascent daughter cell can form a de novo apical domain with its new neighbor. This asymmetric segregation of apical domains is facilitated by a geometrically distinct "apicolateral" subdomain of the lateral surface present in hepatocytes. The polarity protein partitioning-defective 1/microtubule-affinity regulating kinase 2 (Par1b/MARK2 translates this positional landmark to cortical polarity by promoting the apicolateral accumulation of Leu-Gly-Asn repeat-enriched protein (LGN and the capture of nuclear mitotic apparatus protein (NuMA-positive astral microtubules to orientate the mitotic spindle. Proliferating hepatocytes thus display an asymmetric inheritance of their apical domains via a mechanism that involves Par1b and LGN, which we postulate serves the unique tissue architecture of the developing liver parenchyma.

  2. Nucleation, growth, and control of ferroelectric-ferroelastic domains in thin polycrystalline films

    Science.gov (United States)

    Ivry, Yachin; Scott, James F.; Salje, Ekhard K. H.; Durkan, Colm

    2012-11-01

    The unique response of ferroic materials to external excitations facilitates them for diverse technologies, such as nonvolatile memory devices. The primary driving force behind this response is encoded in domain switching. In bulk ferroics, domains switch in a two-step process: nucleation and growth. For ferroelectrics, this can be explained by the Kolmogorov-Avrami-Ishibashi (KAI) model. Nevertheless, it is unclear whether domains remain correlated in finite geometries, as required by the KAI model. Moreover, although ferroelastic domains exist in many ferroelectrics, experimental limitations have hindered the study of their switching mechanisms. This uncertainty limits our understanding of domain switching and controllability, preventing thin-film and polycrystalline ferroelectrics from reaching their full technological potential. Here we used piezoresponse force microscopy to study the switching mechanisms of ferroelectric-ferroelastic domains in thin polycrystalline Pb0.7Zr0.3TiO3 films at the nanometer scale. We have found that switched biferroic domains can nucleate at multiple sites with a coherence length that may span several grains, and that nucleators merge to form mesoscale domains, in a manner consistent with that expected from the KAI model.

  3. Single Crystalline Film of Hexagonal Boron Nitride Atomic Monolayer by Controlling Nucleation Seeds and Domains

    OpenAIRE

    Qinke Wu; Ji-Hoon Park; Sangwoo Park; Seong Jun Jung; Hwansoo Suh; Noejung Park; Winadda Wongwiriyapan; Sungjoo Lee; Young Hee Lee; Young Jae Song

    2015-01-01

    A monolayer hexagonal boron nitride (h-BN) film with controllable domain morphology and domain size (varying from less than 1 μm to more than 100 μm) with uniform crystalline orientation was successfully synthesized by chemical vapor deposition (CVD). The key for this extremely large single crystalline domain size of a h-BN monolayer is a decrease in the density of nucleation seeds by increasing the hydrogen gas flow during the h-BN growth. Moreover, the well-defined shape of h-BN flakes can ...

  4. A MATLAB GUI for learning controller design in the frequency domain

    OpenAIRE

    Mitchell, Richard

    2014-01-01

    A MATLAB GUI is presented which is used to help students learn to design controllers in the frequency domain. It complements the author’s two previous GUIs for plotting and identification of systems in the frequency domain. It also incorporates the concept used in the “electronic calculator that makes students think” to assist learning. Positive student feedback affirms that the GUI has helped their understanding.

  5. Graphene Based Surface Plasmon Polariton Modulator Controlled by Ferroelectric Domains in Lithium Niobate

    OpenAIRE

    Hao Wang; Hua Zhao; Guangwei Hu; Siren Li; Hang Su; Jingwen Zhang

    2015-01-01

    We proposed a ferroelectric domain controlled graphene based surface plasmon polariton modulator. Ferroelectricity-induced electronic and optical property tuning of graphene by domain in lithium niobate was theoretically investigated considering both interband and intraband contributions of surface conductivity. With the corrected Sellmeier equation of lithium niobate, the propagation of transverse magnetic mode surface plasmon polaritons in an air/graphene/lithium niobate structure was studi...

  6. Control of antiferromagnetic domain distribution via polarization-dependent optical annealing.

    Science.gov (United States)

    Higuchi, Takuya; Kuwata-Gonokami, Makoto

    2016-01-01

    The absence of net magnetization inside antiferromagnetic domains has made the control of their spatial distribution quite challenging. Here we experimentally demonstrate an optical method for controlling antiferromagnetic domain distributions in MnF2. Reduced crystalline symmetry can couple an order parameter with non-conjugate external stimuli. In the case of MnF2, time-reversal symmetry is macroscopically broken reflecting the different orientations of the two magnetic sublattices. Thus, it exhibits different absorption coefficients between two orthogonal linear polarizations below its antiferromagnetic transition temperature under an external magnetic field. Illumination with linearly polarized laser light under this condition selectively destructs the formation of a particular antiferromagnetic order via heating. As a result, the other antiferromagnetic order is favoured inside the laser spot, achieving spatially localized selection of an antiferromagnetic order. Applications to control of interface states at antiferromagnetic domain boundaries, exchange bias and control of spin currents are expected. PMID:26911337

  7. Low-Cost Control Problems on Perforated and Non-Perforated Domains

    Indian Academy of Sciences (India)

    S Kesavan; T Muthukumar

    2008-02-01

    We study the homogenization of a class of optimal control problems whose state equations are given by second order elliptic boundary value problems with oscillating coefficients posed on perforated and non-perforated domains. We attempt to describe the limit problem when the cost of the control is also of the same order as that describing the oscillations of the coefficients. We study the situations where the control and the state are both defined over the entire domain or when both are defined on the boundary.

  8. Kalman Based Finite State Controller for Partially Observable Domains

    Directory of Open Access Journals (Sweden)

    H. Levent Akin

    2008-11-01

    Full Text Available A real world environment is often partially observable by the agents either because of noisy sensors or incomplete perception. Moreover, it has continuous state space in nature, and agents must decide on an action for each point in internal continuous belief space. Consequently, it is convenient to model this type of decisionmaking problems as Partially Observable Markov Decision Processes (POMDPs with continuous observation and state space. Most of the POMDP methods whether approximate or exact assume that the underlying world dynamics or POMDP parameters such as transition and observation probabilities are known. However, for many real world environments it is very difficult if not impossible to obtain such information. We assume that only the internal dynamics of the agent, such as the actuator noise, interpretation of the sensor suite, are known. Using these internal dynamics, our algorithm, namely Kalman Based Finite State Controller (KBFSC, constructs an internal world model over the continuous belief space, represented by a finite state automaton. Constructed automaton nodes are points of the continuous belief space sharing a common best action and a common uncertainty level. KBFSC deals with continuous Gaussian-based POMDPs. It makes use of Kalman Filter for belief state estimation, which also is an efficient method to prune unvisited segments of the belief space and can foresee the reachable belief points approximately calculating the horizon N policy. KBFSC does not use an "explore and update" approach in the value calculation as TD-learning. Therefore KBFSC does not have an extensive exploration-exploitation phase. Using the MDP case reward and the internal dynamics of the agent, KBFSC can automatically construct the finite state automaton (FSA representing the approximate optimal policy without the need for discretization of the state and observation space. Moreover, the policy always converges for POMDP problems.

  9. Surgical treatments for vaginal apical prolapse.

    Science.gov (United States)

    Kong, Mi Kyung; Bai, Sang Wook

    2016-07-01

    Pelvic organ prolapse is a common condition, occurring in up to 11% of women in the United States. Often, pelvic organ prolapse recurs after surgery; when it recurs after hysterectomy, it frequently presents as vaginal apical prolapse. There are many different surgical treatments for vaginal apical prolapse; among them, abdominal sacral colpopexy is considered the gold standard. However, recent data reveal that other surgical procedures also result in good outcome. This review discusses the various surgical treatments for vaginal apical prolapse including their risks and benefits. PMID:27462591

  10. Evaluation of data analytic approaches to generating cross-domain mappings of controlled science vocabularies

    Science.gov (United States)

    Zednik, S.

    2015-12-01

    Recent data publication practices have made increasing amounts of diverse datasets available online for the general research community to explore and integrate. Even with the abundance of data online, relevant data discovery and successful integration is still highly dependent upon the data being published with well-formed and understandable metadata. Tagging a dataset with well-known or controlled community terms is a common mechanism to indicate the intended purpose, subject matter, or other relevant facts of a dataset, however controlled domain terminology can be difficult for cross-domain researchers to interpret and leverage. It is also a challenge for integration portals to successfully provide cross-domain search capabilities over data holdings described using many different controlled vocabularies. Mappings between controlled vocabularies can be challenging because communities frequently develop specialized terminologies and have highly specific and contextual usages of common words. Despite this specificity it is highly desirable to produce cross-domain mappings to support data integration. In this contribution we evaluate the applicability of several data analytic techniques for the purpose of generating mappings between hierarchies of controlled science terms. We hope our efforts initiate more discussion on the topic and encourage future mapping efforts.

  11. Unfolding of a Temperature-Sensitive Domain Controls Voltage-Gated Channel Activation.

    Science.gov (United States)

    Arrigoni, Cristina; Rohaim, Ahmed; Shaya, David; Findeisen, Felix; Stein, Richard A; Nurva, Shailika Reddy; Mishra, Smriti; Mchaourab, Hassane S; Minor, Daniel L

    2016-02-25

    Voltage-gated ion channels (VGICs) are outfitted with diverse cytoplasmic domains that impact function. To examine how such elements may affect VGIC behavior, we addressed how the bacterial voltage-gated sodium channel (BacNa(V)) C-terminal cytoplasmic domain (CTD) affects function. Our studies show that the BacNa(V) CTD exerts a profound influence on gating through a temperature-dependent unfolding transition in a discrete cytoplasmic domain, the neck domain, proximal to the pore. Structural and functional studies establish that the BacNa(V) CTD comprises a bi-partite four-helix bundle that bears an unusual hydrophilic core whose integrity is central to the unfolding mechanism and that couples directly to the channel activation gate. Together, our findings define a general principle for how the widespread four-helix bundle cytoplasmic domain architecture can control VGIC responses, uncover a mechanism underlying the diverse BacNa(V) voltage dependencies, and demonstrate that a discrete domain can encode the temperature-dependent response of a channel. PMID:26919429

  12. Membrane domains and polarized trafficking of sphingolipids

    NARCIS (Netherlands)

    Maier, O; Slimane, TA; Hoekstra, D

    2001-01-01

    The plasma membrane of polarized cells consists of distinct domains, the apical and basolateral membrane that are characterized by a distinct lipid and protein content. Apical protein transport is largely mediated by (glyco)sphingolipid-cholesterol enriched membrane microdomains, so called rafts. In

  13. Effects of the airwave in time-domain marine controlled-source electromagnetics

    NARCIS (Netherlands)

    Hunziker, J.W.; Slob, E.C.; Mulder, W.

    2011-01-01

    In marine time-domain controlled-source electromagnetics (CSEM), there are two different acquisition methods: with horizontal sources for fast and simple data acquisition or with vertical sources for minimizing the effects of the airwave. Illustrations of the electric field as a function of space an

  14. Multi-agent coordination strategy estimation method based on control domain

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    For estimation group competition and multiagent coordination strategy, this paper introduces a notion based on multiagent group. According to the control domain, it analyzes the multiagent strategy during competi tion in the macroscopic. It has been adopted in robot soccer and result enunciates that our method does not de pend on competition result. It can objectively quantitatively estimate coordination strategy.

  15. Optimal Vibration Control for Half-Car Suspension on In-Vehicle Networks in Delta Domain

    Directory of Open Access Journals (Sweden)

    Jing Lei

    2013-01-01

    Full Text Available The paper explores the optimal vibration control design problem for a half-car suspension working on in-vehicle networks in delta domain. First, the original suspension system with ECU-actuator delay and sensor-ECU delay is modeled. By using delta operators, the original system is transformed into an associated sampled-data system with time delays in delta domain. After model transformation, the sampled-data system equation is reduced to one without actuator delays and convenient to calculate the states with nonintegral time delay. Therefore, the sampled-data optimal vibration control law can be easily obtained deriving from a Riccati equation and a Stein equation of delta domain. The feedforward control term and the control memory terms designed in the control law ensure the compensation for the effects produced by disturbance and actuator delay, respectively. Moreover, an observer is constructed to implement the physical realizability of the feedforward term and solve the immeasurability problem of some state variables. A half-car suspension model with delays is applied to simulate the responses through the designed controller. Simulation results illustrate the effectiveness of the proposed controller and the simplicity of the designing approach.

  16. Local electrical control of magnetic order and orientation by ferroelastic domain arrangements just above room temperature.

    Science.gov (United States)

    Phillips, L C; Cherifi, R O; Ivanovskaya, V; Zobelli, A; Infante, I C; Jacquet, E; Guiblin, N; Ünal, A A; Kronast, F; Dkhil, B; Barthélémy, A; Bibes, M; Valencia, S

    2015-01-01

    Ferroic materials (ferromagnetic, ferroelectric, ferroelastic) usually divide into domains with different orientations of their order parameter. Coupling between different ferroic systems creates new functionalities, for instance the electrical control of macroscopic magnetic properties including magnetization and coercive field. Here we show that ferroelastic domains can be used to control both magnetic order and magnetization direction at the nanoscale with a voltage. We use element-specific X-ray imaging to map the magnetic domains as a function of temperature and voltage in epitaxial FeRh on ferroelastic BaTiO3. Exploiting the nanoscale phase-separation of FeRh, we locally interconvert between ferromagnetic and antiferromagnetic states with a small electric field just above room temperature. Imaging and ab initio calculations show the antiferromagnetic phase of FeRh is favoured by compressive strain on c-oriented BaTiO3 domains, and the resultant magnetoelectric coupling is larger and more reversible than previously reported from macroscopic measurements. Our results emphasize the importance of nanoscale ferroic domain structure and the promise of first-order transition materials to achieve enhanced coupling in artificial multiferroics. PMID:25969926

  17. Local electrical control of magnetic order and orientation by ferroelastic domain arrangements just above room temperature

    Science.gov (United States)

    Phillips, L. C.; Cherifi, R. O.; Ivanovskaya, V.; Zobelli, A.; Infante, I. C.; Jacquet, E.; Guiblin, N.; Ünal, A. A.; Kronast, F.; Dkhil, B.; Barthélémy, A.; Bibes, M.; Valencia, S.

    2015-05-01

    Ferroic materials (ferromagnetic, ferroelectric, ferroelastic) usually divide into domains with different orientations of their order parameter. Coupling between different ferroic systems creates new functionalities, for instance the electrical control of macroscopic magnetic properties including magnetization and coercive field. Here we show that ferroelastic domains can be used to control both magnetic order and magnetization direction at the nanoscale with a voltage. We use element-specific X-ray imaging to map the magnetic domains as a function of temperature and voltage in epitaxial FeRh on ferroelastic BaTiO3. Exploiting the nanoscale phase-separation of FeRh, we locally interconvert between ferromagnetic and antiferromagnetic states with a small electric field just above room temperature. Imaging and ab initio calculations show the antiferromagnetic phase of FeRh is favoured by compressive strain on c-oriented BaTiO3 domains, and the resultant magnetoelectric coupling is larger and more reversible than previously reported from macroscopic measurements. Our results emphasize the importance of nanoscale ferroic domain structure and the promise of first-order transition materials to achieve enhanced coupling in artificial multiferroics.

  18. A transferrin-like GPI-linked iron-binding protein in detergent-insoluble noncaveolar microdomains at the apical surface of fetal intestinal epithelial cells

    DEFF Research Database (Denmark)

    Danielsen, E M; van Deurs, B

    1995-01-01

    ultracryosections of mucosal tissue, the protein was localized to the apical surface of the enterocytes, whereas it was absent from the basolateral plasma membrane. Interestingly, it was mainly found in patches of flat or invaginated apical membrane domains rather than at the surface of microvilli. Caveolae were...

  19. A Domain-Independent Source of Cognitive Control for Task Sets: Shifting Spatial Attention and Switching Categorization Rules

    OpenAIRE

    Chiu, Yu-Chin; Yantis, Steven

    2009-01-01

    In order to optimize task performance as circumstances unfold, cognitive control mechanisms configure the brain to prepare for upcoming events through voluntary shifts in task set. A foundational unanswered question concerns whether different domains of cognitive control (e.g., spatial attention shifts, shifts between categorization rules, or shifts between stimulus-response mapping rules) are associated with separate, domain-specific control mechanisms, or whether a common, domain-independen...

  20. The apical complex provides a regulated gateway for secretion of invasion factors in Toxoplasma.

    Directory of Open Access Journals (Sweden)

    Nicholas J Katris

    2014-04-01

    Full Text Available The apical complex is the definitive cell structure of phylum Apicomplexa, and is the focus of the events of host cell penetration and the establishment of intracellular parasitism. Despite the importance of this structure, its molecular composition is relatively poorly known and few studies have experimentally tested its functions. We have characterized a novel Toxoplasma gondii protein, RNG2, that is located at the apical polar ring--the common structural element of apical complexes. During cell division, RNG2 is first recruited to centrosomes immediately after their duplication, confirming that assembly of the new apical complex commences as one of the earliest events of cell replication. RNG2 subsequently forms a ring, with the carboxy- and amino-termini anchored to the apical polar ring and mobile conoid, respectively, linking these two structures. Super-resolution microscopy resolves these two termini, and reveals that RNG2 orientation flips during invasion when the conoid is extruded. Inducible knockdown of RNG2 strongly inhibits host cell invasion. Consistent with this, secretion of micronemes is prevented in the absence of RNG2. This block, however, can be fully or partially overcome by exogenous stimulation of calcium or cGMP signaling pathways, respectively, implicating the apical complex directly in these signaling events. RNG2 demonstrates for the first time a role for the apical complex in controlling secretion of invasion factors in this important group of parasites.

  1. Stress-mediated magnetoelectric control of ferromagnetic domain wall position in multiferroic heterostructures

    Science.gov (United States)

    Mathurin, Théo; Giordano, Stefano; Dusch, Yannick; Tiercelin, Nicolas; Pernod, Philippe; Preobrazhensky, Vladimir

    2016-02-01

    The motion of a ferromagnetic domain wall in nanodevices is usually induced by means of external magnetic fields or polarized currents. Here, we demonstrate the possibility to reversibly control the position of a Néel domain wall in a ferromagnetic nanostripe through a uniform mechanical stress. The latter is generated by an electro-active substrate combined with the nanostripe in a multiferroic heterostructure. We develop a model describing the magnetization distribution in the ferromagnetic material, properly taking into account the magnetoelectric coupling. Through its numerical implementation, we obtain the relationship between the electric field applied to the piezoelectric substrate and the position of the magnetic domain wall in the nanostripe. As an example, we analyze a structure composed of a PMN-PT substrate and a TbCo2/FeCo composite nanostripe.

  2. Control systems using modal domain optical fiber sensors for smart structure applications

    Science.gov (United States)

    Lindner, Douglas K.; Reichard, Karl M.

    1991-01-01

    Recently, a new class of sensors has emerged for structural control which respond to environmental changes over a significant gauge length; these sensors are called distributed-effect sensors. These sensors can be fabricated with spatially varying sensitivity to the distributed measurand, and can be configured to measure a variety of structural parameters which can not be measured directly using point sensors. Examples of distributed-effect sensors include piezoelectric film, holographic sensors, and modal domain optical fiber sensors. Optical fiber sensors are particularly attractive for smart structure applications because they are flexible, have low mass, and can easily be embedded directly into materials. In this paper we describe the implementation of weighted modal domain optical fiber sensors. The mathematical model of the modal domain optical fiber sensor model is described and used to derive an expression for the sensor sensitivity. The effects of parameter variations on the sensor sensitivity are demonstrated to illustrate methods of spatially varying the sensor sensitivity.

  3. Ligand-binding domains of nuclear receptors facilitate tight control of split CRISPR activity.

    Science.gov (United States)

    Nguyen, Duy P; Miyaoka, Yuichiro; Gilbert, Luke A; Mayerl, Steven J; Lee, Brian H; Weissman, Jonathan S; Conklin, Bruce R; Wells, James A

    2016-01-01

    Cas9-based RNA-guided nuclease (RGN) has emerged to be a versatile method for genome editing due to the ease of construction of RGN reagents to target specific genomic sequences. The ability to control the activity of Cas9 with a high temporal resolution will facilitate tight regulation of genome editing processes for studying the dynamics of transcriptional regulation or epigenetic modifications in complex biological systems. Here we show that fusing ligand-binding domains of nuclear receptors to split Cas9 protein fragments can provide chemical control over split Cas9 activity. The method has allowed us to control Cas9 activity in a tunable manner with no significant background, which has been challenging for other inducible Cas9 constructs. We anticipate that our design will provide opportunities through the use of different ligand-binding domains to enable multiplexed genome regulation of endogenous genes in distinct loci through simultaneous chemical regulation of orthogonal Cas9 variants. PMID:27363581

  4. Ligand-binding domains of nuclear receptors facilitate tight control of split CRISPR activity

    Science.gov (United States)

    Nguyen, Duy P.; Miyaoka, Yuichiro; Gilbert, Luke A.; Mayerl, Steven J.; Lee, Brian H.; Weissman, Jonathan S.; Conklin, Bruce R.; Wells, James A.

    2016-01-01

    Cas9-based RNA-guided nuclease (RGN) has emerged to be a versatile method for genome editing due to the ease of construction of RGN reagents to target specific genomic sequences. The ability to control the activity of Cas9 with a high temporal resolution will facilitate tight regulation of genome editing processes for studying the dynamics of transcriptional regulation or epigenetic modifications in complex biological systems. Here we show that fusing ligand-binding domains of nuclear receptors to split Cas9 protein fragments can provide chemical control over split Cas9 activity. The method has allowed us to control Cas9 activity in a tunable manner with no significant background, which has been challenging for other inducible Cas9 constructs. We anticipate that our design will provide opportunities through the use of different ligand-binding domains to enable multiplexed genome regulation of endogenous genes in distinct loci through simultaneous chemical regulation of orthogonal Cas9 variants. PMID:27363581

  5. Continuous Magnetoelectric Control in Multiferroic DyMnO3 Films with Twin-like Domains

    Science.gov (United States)

    Lu, Chengliang; Deniz, Hakan; Li, Xiang; Liu, Jun-Ming; Cheong, Sang-Wook

    2016-02-01

    The magnetic control of ferroelectric polarization is currently a central topic in the multiferroic researches, owing to the related gigantic magnetoelectric coupling and fascinating physics. Although a bunch of novel magnetoelectric effect have been discovered in multiferroics of magnetic origin, the manipulation of polarization was found to be fundamentally determined by the microscopic origin in a certain multiferroic phase, hindering the development of unusual magnetoelectric control. Here, we report emergent magnetoelectric control in DyMnO3/Nb:SrTiO3 (001) films showing twin-like domain structure. Our results demonstrate interesting magnetically induced partial switch of polarization due to the coexistence of polarizations along both the a-axis and c-axis enabled by the twin-like domain structure in DyMnO3 films, despite the polarization-switch was conventionally believed to be a one-step event in the bulk counterpart. Moreover, a continuous and periodic control of macroscopic polarization by an in-plane rotating magnetic field is evidenced in the thin films. This distinctive magnetic manipulation of polarization is the consequence of the cooperative action of the twin-like domains and the dual magnetic origin of polarization, which promises additional applications using the magnetic control of ferroelectricity.

  6. Controlled creation and displacement of charged domain walls in ferroelectric thin films

    Science.gov (United States)

    Feigl, L.; Sluka, T.; McGilly, L. J.; Crassous, A.; Sandu, C. S.; Setter, N.

    2016-08-01

    Charged domain walls in ferroelectric materials are of high interest due to their potential use in nanoelectronic devices. While previous approaches have utilized complex scanning probe techniques or frustrative poling here we show the creation of charged domain walls in ferroelectric thin films during simple polarization switching using either a conductive probe tip or patterned top electrodes. We demonstrate that ferroelectric switching is accompanied - without exception - by the appearance of charged domain walls and that these walls can be displaced and erased reliably. We ascertain from a combination of scanning probe microscopy, transmission electron microscopy and phase field simulations that creation of charged domain walls is a by-product of, and as such is always coupled to, ferroelectric switching. This is due to the (110) orientation of the tetragonal (Pb,Sr)TiO3 thin films and the crucial role played by the limited conduction of the LSMO bottom electrode layer used in this study. This work highlights that charged domain walls, far from being exotic, unstable structures, as might have been assumed previously, can be robust, stable easily-controlled features in ferroelectric thin films.

  7. Roles of external and cellular Cl- ions on the activation of an apical electrodiffusional Cl- pathway in toad skin.

    Science.gov (United States)

    Procopio, J; Lacaz-Vieira, F

    1990-07-01

    This study is concerned with the short-circuit current, Isc, responses of the Cl(-)-transporting cells of toad skin submitted to sudden changes of the external Cl- concentration, [Cl]o. Sudden changes of [Cl]o, carried out under apical membrane depolarization, allowed comparison of the roles of [Cl]o and [Cl]cell on the activation of the apical Cl- pathways. Equilibration of short-circuited skins symmetrically in K-Ringer's solutions of different Cl- concentrations permitted adjustment of [Cl]cell to different levels. For a given Cl- concentration (in the range of 11.7 to 117 mM) on both sides of a depolarized apical membrane, this structure exhibits a high Cl- permeability, P(Cl)apical. On the other hand, for the same range of [Cl]cell but with [Cl]o = 0, P(Cl)apical is reduced to negligible values. These observations indicate that when the apical membrane is depolarized P(Cl)apical is modulated by [Cl]o; in the absence of external Cl- ions, intracellular Cl- is not sufficient to activate P(Cl)apical. Computer simulation shows that the fast Cl- currents induced across the apical membrane by sudden shifts of [Cl]o from a control equilibrium value strictly follow the laws of electrodiffusion. For each experimental group, the computer-generated Isc versus [( Cl]cell - [Cl]o) curve which best fits the experimental data can only be obtained by a unique pair of P(Cl)apical and Rb (resistance of the basolateral membrane), thus allowing the calculation of these parameters. The electrodiffusional behavior of the net Cl- flux across the apical membrane supports the channel nature of the apical Cl- pathways in the Cl(-)-transporting cells. Cl- ions contribute significantly to the overall conductance of the basolateral membrane even in the presence of a high K concentration in the internal solution. PMID:1698229

  8. Apical root resorption in orthodontically treated adults.

    Science.gov (United States)

    Baumrind, S; Korn, E L; Boyd, R L

    1996-09-01

    This study analyzed the relationship in orthodontically treated adults between upper central incisor displacement measured on lateral cephalograms and apical root resorption measured on anterior periapical x-ray films. A multiple linear regression examined incisor displacements in four directions (retraction, advancement, intrusion, and extrusion) as independent variables, attempting to account for observed differences in the dependent variable, resorption. Mean apical resorption was 1.36 mm (sd +/- 1.46, n = 73). Mean horizontal displacement of the apex was -0.83 mm (sd +/- 1.74, n = 67); mean vertical displacement was 0.19 mm (sd +/- 1.48, n = 67). The regression coefficients for the intercept and for retraction were highly significant; those for extrusion, intrusion, and advancement were not. At the 95% confidence level, an average of 0.99 mm (se = +/- 0.34) of resorption was implied in the absence of root displacement and an average of 0.49 mm (se = +/- 0.14) of resorption was implied per millimeter of retraction. R2 for all four directional displacement variables (DDVs) taken together was only 0.20, which implied that only a relatively small portion of the observed apical resorption could be accounted for by tooth displacement alone. In a secondary set of univariate analyses, the associations between apical resorption and each of 14 additional treatment-related variables were examined. Only Gender, Elapsed Time, and Total Apical Displacement displayed statistically significant associations with apical resorption. Additional multiple regressions were then performed in which the data for each of these three statistically significant variables were considered separately, with the data for the four directional displacement variables. The addition of information on Elapsed Time or Total Apical Displacement did not explain a significant additional portion of the variability in apical resorption. On the other hand, the addition of information on Gender to the

  9. The effects of multi-domain versus single-domain cognitive training in non-demented older people: a randomized controlled trial

    Directory of Open Access Journals (Sweden)

    Cheng Yan

    2012-03-01

    Full Text Available Abstract Background Whether healthy older people can benefit from cognitive training (CogTr remains controversial. This study explored the benefits of CogTr in community dwelling, healthy, older adults and compared the effects of single-domain with multi-domain CogTr interventions. Methods A randomized, controlled, 3-month trial of CogTr with double-blind assessments at baseline and immediate, 6-month and 12-month follow-up after training completion was conducted. A total of 270 healthy Chinese older people, 65 to 75 years old, were recruited from the Ganquan-area community in Shanghai. Participants were randomly assigned to three groups: multi-domain CogTr, single-domain CogTr, and a wait-list control group. Twenty-four sessions of CogTr were administrated to the intervention groups over a three-month period. Six months later, three booster training sessions were offered to 60% of the initial training participants. The Repeatable Battery for the Assessment of Neuropsychological Status (RBANS, Form A, the Color Word Stroop test (CWST, the Visual Reasoning test and the Trail Making test (TMT were used to assess cognitive function. Results Multi-domain CogTr produced statistically significant training effects on RBANS, visual reasoning, and immediate and delayed memory, while single-domain CogTr showed training effects on RBANS, visual reasoning, word interference, and visuospatial/constructional score (all P Conclusions Cognitive training can improve memory, visual reasoning, visuospatial construction, attention and neuropsychological status in community-living older people and can help maintain their functioning over time. Multi-domain CogTr enhanced memory proficiency, while single-domain CogTr augmented visuospatial/constructional and attention abilities. Multi-domain CogTr had more advantages in training effect maintenance. Clinical Trial Registration Chinese Clinical Trial Registry. Registration number: ChiCTR-TRC-09000732.

  10. Genetics of cognitive control: Implications for Nimh's research domain criteria initiative.

    Science.gov (United States)

    Glahn, David C; Knowles, Emma E M; Pearlson, Godfrey D

    2016-01-01

    Cognitive control refers to a set of mental processes that modulate other cognitive and emotional systems in service of goal-directed adaptive behavior. There is growing support for the notion that cognitive control abnormalities are a central component of many of the neuropsychological deficits observed in individuals with mental illnesses, particularly those with psychotic disorders. NIMH's research domain criteria (RDoC) initiative, which is designed to develop biologically informed constructs to better understand psychopathology, designated cognitive control a construct within the cognitive systems domain. Identification of genes that influence cognitive control or its supportive brain systems will improve our understating of the RDoC construct and provide candidate genes for psychotic disorders. We examine evidence for cognitive control deficits in psychosis, determine if these measures could be useful endophenotypes, and explore work linking genetic variation to cognitive control performance. While there is a wealth of evidence to support the notion the cognitive control is a valid endophenotype for psychosis, its genetic underpinning remains ill characterized. However, existing work provides a promising foundation on which future endeavors might build. Confirming existing individual gene associations will go some way to expanding our understanding of the genetics of cognitive control, and by extension, psychotic disorders. Yet, to truly understand the molecular underpinnings of such complex traits, it may be necessary to evaluate genes in tandem, focusing not on single genes but rather on empirically derived gene sets or on functionally defined networks of genes. PMID:26768522

  11. An agent-based negotiation approach for balancing multiple coupled control domains

    DEFF Research Database (Denmark)

    Umair, Aisha; Clausen, Anders; Jørgensen, Bo Nørregaard

    2015-01-01

    Solving multi-objective multi-issue negotiation problems involving interdependent issues distributed among multiple control domains is inherent to most non-trivial cyber-physical systems. In these systems, the coordinated operation of interconnected subsystems performing autonomous control...... is essential to achieve overall system goals. In spite of its importance, the area has received limited attention to date. In this paper, we propose an innovative agent-based coordination approach for coordinating and controlling interconnected subsystems in cyber-physical systems with interdependent issues...

  12. Remarks on Hierarchic Control for a Linearized Micropolar Fluids System in Moving Domains

    Energy Technology Data Exchange (ETDEWEB)

    Jesus, Isaías Pereira de, E-mail: isaias@ufpi.edu.br [Universidade Federal do Piauí, Dpto. Matemática (Brazil)

    2015-12-15

    We study a Stackelberg strategy subject to the evolutionary linearized micropolar fluids equations in domains with moving boundaries, considering a Nash multi-objective equilibrium (non necessarily cooperative) for the “follower players” (as is called in the economy field) and an optimal problem for the leader player with approximate controllability objective. We will obtain the following main results: the existence and uniqueness of Nash equilibrium and its characterization, the approximate controllability of the linearized micropolar system with respect to the leader control and the existence and uniqueness of the Stackelberg–Nash problem, where the optimality system for the leader is given.

  13. Pathogenesis of apical periodontitis and the causes of endodontic failures.

    Science.gov (United States)

    Nair, P N R

    2004-01-01

    Apical periodontitis is a sequel to endodontic infection and manifests itself as the host defense response to microbial challenge emanating from the root canal system. It is viewed as a dynamic encounter between microbial factors and host defenses at the interface between infected radicular pulp and periodontal ligament that results in local inflammation, resorption of hard tissues, destruction of other periapical tissues, and eventual formation of various histopathological categories of apical periodontitis, commonly referred to as periapical lesions. The treatment of apical periodontitis, as a disease of root canal infection, consists of eradicating microbes or substantially reducing the microbial load from the root canal and preventing re-infection by orthograde root filling. The treatment has a remarkably high degree of success. Nevertheless, endodontic treatment can fail. Most failures occur when treatment procedures, mostly of a technical nature, have not reached a satisfactory standard for the control and elimination of infection. Even when the highest standards and the most careful procedures are followed, failures still occur. This is because there are root canal regions that cannot be cleaned and obturated with existing equipments, materials, and techniques, and thus, infection can persist. In very rare cases, there are also factors located within the inflamed periapical tissue that can interfere with post-treatment healing of the lesion. The data on the biological causes of endodontic failures are recent and scattered in various journals. This communication is meant to provide a comprehensive overview of the etio-pathogenesis of apical periodontitis and the causes of failed endodontic treatments that can be visualized in radiographs as asymptomatic post-treatment periapical radiolucencies. PMID:15574679

  14. Strain-controlled magnetic domain wall propagation in hybrid piezoelectric/ferromagnetic structures.

    Science.gov (United States)

    Lei, Na; Devolder, Thibaut; Agnus, Guillaume; Aubert, Pascal; Daniel, Laurent; Kim, Joo-Von; Zhao, Weisheng; Trypiniotis, Theodossis; Cowburn, Russell P; Chappert, Claude; Ravelosona, Dafiné; Lecoeur, Philippe

    2013-01-01

    The control of magnetic order in nanoscale devices underpins many proposals for integrating spintronics concepts into conventional electronics. A key challenge lies in finding an energy-efficient means of control, as power dissipation remains an important factor limiting future miniaturization of integrated circuits. One promising approach involves magnetoelectric coupling in magnetostrictive/piezoelectric systems, where induced strains can bear directly on the magnetic anisotropy. While such processes have been demonstrated in several multiferroic heterostructures, the incorporation of such complex materials into practical geometries has been lacking. Here we demonstrate the possibility of generating sizeable anisotropy changes, through induced strains driven by applied electric fields, in hybrid piezoelectric/spin-valve nanowires. By combining magneto-optical Kerr effect and magnetoresistance measurements, we show that domain wall propagation fields can be doubled under locally applied strains. These results highlight the prospect of constructing low-power domain wall gates for magnetic logic devices. PMID:23340418

  15. ASPP2 links the apical lateral polarity complex to the regulation of YAP activity in epithelial cells.

    Directory of Open Access Journals (Sweden)

    Christophe Royer

    Full Text Available The Hippo pathway, by tightly controlling the phosphorylation state and activity of the transcription cofactors YAP and TAZ is essential during development and tissue homeostasis whereas its deregulation may lead to cancer. Recent studies have linked the apicobasal polarity machinery in epithelial cells to components of the Hippo pathway and YAP and TAZ themselves. However the molecular mechanism by which the junctional pool of YAP proteins is released and activated in epithelial cells remains unknown. Here we report that the tumour suppressor ASPP2 forms an apical-lateral polarity complex at the level of tight junctions in polarised epithelial cells, acting as a scaffold for protein phosphatase 1 (PP1 and junctional YAP via dedicated binding domains. ASPP2 thereby directly induces the dephosphorylation and activation of junctional YAP. Collectively, this study unearths a novel mechanistic paradigm revealing the critical role of the apical-lateral polarity complex in activating this localised pool of YAP in vitro, in epithelial cells, and in vivo, in the murine colonic epithelium. We propose that this mechanism may commonly control YAP functions in epithelial tissues.

  16. Edge-controlled growth and kinetics of single-crystal graphene domains by chemical vapor deposition

    OpenAIRE

    Ma, Teng; Ren, Wencai; Zhang, Xiuyun; Liu, Zhibo; Gao, Yang; Yin, Li-Chang; Ma, Xiu-Liang; Ding, Feng; Cheng, Hui-Ming

    2013-01-01

    Controlled synthesis of wafer-sized single crystalline high-quality graphene is a great challenge of graphene growth by chemical vapor deposition because of the complicated kinetics at edges that govern the growth process. Here we report the synthesis of single-crystal graphene domains with tunable edges from zigzag to armchair via a growth–etching–regrowth process. Both growth and etching of graphene are strongly dependent on the edge structure. This growth/etching behavior is well explained...

  17. Control of multiferroic domains by external electric fields in TbMnO3

    OpenAIRE

    Stein, Jonas; Baum, Max; Holbein, Simon; Hutanu, Vladimir; Komarek, Alexander C.; Braden, Markus

    2015-01-01

    The control of multiferroic domains through external electric fields has been studied by dielectric measurements and by polarized neutron diffraction on single-crystalline TbMnO$_3$. Full hysteresis cycles were recorded by varying an external field of the order of several kV/mm and by recording the chiral magnetic scattering as well as the charge in a sample capacitor. Both methods yield comparable coercive fields that increase upon cooling.

  18. Control of multiferroic domains by external electric fields in TbMnO3

    Science.gov (United States)

    Stein, J.; Baum, M.; Holbein, S.; Cronert, T.; Hutanu, V.; Komarek, A. C.; Braden, M.

    2015-11-01

    The control of multiferroic domains through external electric fields has been studied by dielectric measurements and by polarized neutron diffraction on single-crystalline TbMnO3. Full hysteresis cycles were recorded by varying an external field of the order of several kV mm-1 and by recording the chiral magnetic scattering as well as the charge in a sample capacitor. Both methods yield comparable coercive fields that increase upon cooling.

  19. Control of multiferroic domains by external electric fields in TbMnO₃.

    Science.gov (United States)

    Stein, J; Baum, M; Holbein, S; Cronert, T; Hutanu, V; Komarek, A C; Braden, M

    2015-11-11

    The control of multiferroic domains through external electric fields has been studied by dielectric measurements and by polarized neutron diffraction on single-crystalline TbMnO3. Full hysteresis cycles were recorded by varying an external field of the order of several kV mm(-1) and by recording the chiral magnetic scattering as well as the charge in a sample capacitor. Both methods yield comparable coercive fields that increase upon cooling. PMID:26452106

  20. Ethylene Controls Autophosphorylation of the Histidine Kinase Domain in Ethylene Receptor ETR1

    Institute of Scientific and Technical Information of China (English)

    Jan Voet-van-Vormizeele; Georg Groth

    2008-01-01

    Perception of the phytohormone ethylene is accomplished by a small family of integral membrane receptors.In Arabidopsis,five ethylene receptor proteins are known,including ethylene resistant 1 (ETR1).The hydrophobic aminoterminal domain of these receptors contains the ethylene-binding site while the carboxyl-terminal part consists of a histidine kinase domain and a response regulator domain,which are well known elements found in bacterial two-component signaling.The soluble membrane-extrinsic carboxyl-terminal part of the receptor,which is likely to play an important role in signal transduction,showed intrinsic kinase activity when expressed and purified on its own.However,a correlation between signal input and autokinase activity was not established in these studies,as receptors were missing the transmembrane amino-terminal sensor domain.Thus,it is still unclear whether autophosphorylation occurs in response to perception of the ethylene signal.Here,we report on autophosphorylation studies of purified full-length ETR1.Autokinase activity of the purified receptor is controlled by ethylene or by ethylene agonists like the π-acceptor compound cyanide.In fact,both signal molecules were able to completely turn off the intrinsic kinase activity.Furthermore,the observed inhibition of autophosphorylation in ETR1 by both molecules could be prevented when the ethylene antagonist 1-methyl-cyclopropene (MCP) was applied.

  1. Comparison of apical sealing and periapical extrusion of the ThermaFil obturation technique with and without MTA as an apical barrier: An in vitro study

    Directory of Open Access Journals (Sweden)

    Satish Kumar

    2011-01-01

    Full Text Available Aim: The aim of the study was to compare the conventional ThermaFil obturation technique and ThermaFil obturation with mineral trioxide aggregate (MTA as an apical barrier, with regard to apical sealing and extrusion. Materials and Methods: Twenty extracted human canines were instrumented using a crown-down technique and divided into two groups. The experimental group was obturated using ThermaFil obturation with MTA as an apical barrier and the control group was obturated using the conventional ThermaFil obturation technique. AH Plus sealer was used in both the groups. Apical extrusion was recorded. Teeth of both the groups were coated with nail polish, except for the apical 3 mm. After 24 h, they were suspended in black India ink for 48 h. Canines were decalcified, rendered transparent, and linear dye penetration was measured under ×40 stereomicroscope. Results: There was a significant extrusion noticed in conventional ThermaFil obturation technique. Frequency of extrusion of sealer and/or gutta-percha was supposed to be evaluated using χ² test, but since the values of the samples of ThermaFil plus MTA group were zero, statistical analysis could not be conducted, whereas linear dye leakage was calculated with Mann-Whitney U test because the distribution was abnormal. Conclusion: Although ThermaFil plus MTA group showed microleakage, extrusion of sealer and the core material was prevented in comparison with conventional ThermaFil obturation technique. It is advantageous to use MTA as an apical plug as there is no fear of apical extrusion and the root canal system can then be packed three dimensionally against this barrier using any thermoplasticized gutta-percha obturation technique.

  2. Control of polarization signal distortion by frequency domain phase conjugation in optical fiber systems

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Optical frequency domain phase conjugation(FDPC) is based on phase conjuga-tion of spectrum of an input signal.It is equivalent to the phase conjugation and the time reversal of the temporal envelope of an input signal.The use of FDPC to con-trol polarization signal distortion in birefringent optical fiber systems is proposed.Evolution of polarization signals in the system using midway FDPC is analyzed theoretically and simulated numerically.It is shown that the distortion of polariza-tion signals can be controlled effectively by FDPC.The impairments due to disper-sion and nonlinear effects can be suppressed simultaneously.

  3. Control of polarization signal distortion by frequency domain phase conjusation in optical fiber systems

    Institute of Scientific and Technical Information of China (English)

    BU Yang; WANG XiangZhao

    2008-01-01

    Optical frequency domain phase conjugation (FDPC) is based on phase conjugation of spectrum of an input signal. It is equivalent to the phase conjugation and the time reversal of the temporal envelope of an input signal. The use of FDPC to con-trol polarization signal distortion in birefringent optical fiber systems is proposed. Evolution of polarization signals in the system using midway FDPC is analyzed theoretically and simulated numerically. It is shown that the distortion of polariza-tion signals can be controlled effectively by FDPC. The impairments due to disper-sion and nonlinear effects can be suppressed simultaneously.

  4. CAMSAP3 orients the apical-to-basal polarity of microtubule arrays in epithelial cells.

    Science.gov (United States)

    Toya, Mika; Kobayashi, Saeko; Kawasaki, Miwa; Shioi, Go; Kaneko, Mari; Ishiuchi, Takashi; Misaki, Kazuyo; Meng, Wenxiang; Takeichi, Masatoshi

    2016-01-12

    Polarized epithelial cells exhibit a characteristic array of microtubules that are oriented along the apicobasal axis of the cells. The minus-ends of these microtubules face apically, and the plus-ends face toward the basal side. The mechanisms underlying this epithelial-specific microtubule assembly remain unresolved, however. Here, using mouse intestinal cells and human Caco-2 cells, we show that the microtubule minus-end binding protein CAMSAP3 (calmodulin-regulated-spectrin-associated protein 3) plays a pivotal role in orienting the apical-to-basal polarity of microtubules in epithelial cells. In these cells, CAMSAP3 accumulated at the apical cortices, and tethered the longitudinal microtubules to these sites. Camsap3 mutation or depletion resulted in a random orientation of these microtubules; concomitantly, the stereotypic positioning of the nucleus and Golgi apparatus was perturbed. In contrast, the integrity of the plasma membrane was hardly affected, although its structural stability was decreased. Further analysis revealed that the CC1 domain of CAMSAP3 is crucial for its apical localization, and that forced mislocalization of CAMSAP3 disturbs the epithelial architecture. These findings demonstrate that apically localized CAMSAP3 determines the proper orientation of microtubules, and in turn that of organelles, in mature mammalian epithelial cells. PMID:26715742

  5. Apical dominance in Alstroemeria cultured in vitro

    NARCIS (Netherlands)

    Pumisutapon, P.; Visser, R.G.F.; Klerk, de G.J.M.

    2009-01-01

    Apical dominance in Alstroemeria is studied to develop an improved propagation protocol for this crop. Four types of explants were prepared: an intact rhizome with two intact shoots (+R+2S), an intact rhizome with two decapitated shoots (+R-2S), a decapitated rhizome with two intact shoots (-R+2S),

  6. Tuning fractional PID controllers for a Steward platform based on frequency domain and artificial intelligence methods

    Science.gov (United States)

    Copot, Cosmin; Zhong, Yu; Ionescu, Clara; Keyser, Robin

    2013-06-01

    In this paper, two methods to tune a fractional-order PI λ D μ controller for a mechatronic system are presented. The first method is based on a genetic algorithm to obtain the parameter values for the fractionalorder PI λ D μ controller by global optimization. The second method used to design the fractional-order PI λ D μ controller relies on an auto-tuning approach by meeting some specifications in the frequency domain. The real-time experiments are conducted using a Steward platform which consists of a table tilted by six servo-motors with a ball on the top of the table. The considered system is a 6 degrees of freedom (d.o.f.) motion platform. The feedback on the position of the ball is obtained from images acquired by a visual sensor mounted above the platform. The fractional-order controllers were implemented and the performances of the steward platform are analyzed.

  7. Attention for speaking: domain-general control from the anterior cingulate cortex in spoken word production

    Directory of Open Access Journals (Sweden)

    Vitoria ePiai

    2013-12-01

    Full Text Available Accumulating evidence suggests that some degree of attentional control is required to regulate and monitor processes underlying speaking. Although progress has been made in delineating the neural substrates of the core language processes involved in speaking, substrates associated with regulatory and monitoring processes have remained relatively underspecified. We report the results of an fMRI study examining the neural substrates related to performance in three attention-demanding tasks varying in the amount of linguistic processing: vocal picture naming while ignoring distractors (picture-word interference, PWI; vocal colour naming while ignoring distractors (Stroop; and manual object discrimination while ignoring spatial position (Simon task. All three tasks had congruent and incongruent stimuli, while PWI and Stroop also had neutral stimuli. Analyses focusing on common activation across tasks identified a portion of the dorsal anterior cingulate cortex that was active in incongruent trials for all three tasks, suggesting that this region subserves a domain-general attentional control function. In the language tasks, this area showed increased activity for incongruent relative to congruent stimuli, consistent with the involvement of domain-general mechanisms of attentional control in word production. The two language tasks also showed activity in anterior-superior temporal gyrus. Activity increased for neutral PWI stimuli (picture and word did not share the same semantic category relative to incongruent (categorically related and congruent stimuli. This finding is consistent with the involvement of language-specific areas in word production, possibly related to retrieval of lexical-semantic information from memory. The current results thus suggest that in addition to engaging language-specific areas for core linguistic processes, speaking also engages the anterior cingulate cortex, a region that is likely implementing domain

  8. The Effect of Smear Layer on Apical Seal of Endodontically Treated Teeth

    Directory of Open Access Journals (Sweden)

    A Farhad

    2004-06-01

    Full Text Available Background: The purpose of this study was to evaluate the effect of smear layer on apical seal of endodontically treated teeth. Methods: Sixty extracted single–rooted human teeth were randomly divided into two experimental groups (n=25 and two control groups (n=5. The teeth were instrumented with K–type files to size 40 and then flared. Apical patency was ensured in all teeth. 5% sodium hypochlorite and 17% Ethylenediamine tetraacetic acid was used as irrigants to remove the smear layer in the second experimental group. The experimental groups were obturated by laterally condensed gutta – percha with Roth 801 sealer. The positive control group was obturated with gutta – percha without sealer. The root surfaces were then coated with nail polish and sticky wax except for the apex in the experimental groups and positive control group. The roots were completely covered in the negative control group. The samples were then immersed in India ink for 1 week at 37°C. Results: The statistical analysis of the results showed that the apical leakage was significantly increased in obturated canals with smear layer. Conclusion: The removal of smear layer might improve the long term apical seal and success of endodontically treated teeth. Keywords: Apical Seal, EDTA, Removal, Sodium Hypochlorite, Smear Layer.

  9. Domain-driven specification techniques simplify the analysis of requirements for the KAON factory central control system

    Energy Technology Data Exchange (ETDEWEB)

    Inwood, C. (Inwood Real-Time Systems Associates, Kinburn, ON (Canada)); Ludgate, G.A.; Dohan, D.A.; Osberg, E.A.; Koscielniak, S. (British Columbia Univ., Vancouver (Canada). TRIUMF Facility)

    1990-08-01

    Domain-driven modelling, outlined in this paper, has been successfully applied to the analysis, specification and design of the KAON Factory central control system (KF-CCS). This advanced object-oriented technique is especially suited to the development of complex systems. Early in the project, four very natural domains were identified which simplified the analysis of requirements. (orig.).

  10. S3QL: A distributed domain specific language for controlled semantic integration of life sciences data

    Directory of Open Access Journals (Sweden)

    de Lencastre Hermínia

    2011-07-01

    Full Text Available Abstract Background The value and usefulness of data increases when it is explicitly interlinked with related data. This is the core principle of Linked Data. For life sciences researchers, harnessing the power of Linked Data to improve biological discovery is still challenged by a need to keep pace with rapidly evolving domains and requirements for collaboration and control as well as with the reference semantic web ontologies and standards. Knowledge organization systems (KOSs can provide an abstraction for publishing biological discoveries as Linked Data without complicating transactions with contextual minutia such as provenance and access control. We have previously described the Simple Sloppy Semantic Database (S3DB as an efficient model for creating knowledge organization systems using Linked Data best practices with explicit distinction between domain and instantiation and support for a permission control mechanism that automatically migrates between the two. In this report we present a domain specific language, the S3DB query language (S3QL, to operate on its underlying core model and facilitate management of Linked Data. Results Reflecting the data driven nature of our approach, S3QL has been implemented as an application programming interface for S3DB systems hosting biomedical data, and its syntax was subsequently generalized beyond the S3DB core model. This achievement is illustrated with the assembly of an S3QL query to manage entities from the Simple Knowledge Organization System. The illustrative use cases include gastrointestinal clinical trials, genomic characterization of cancer by The Cancer Genome Atlas (TCGA and molecular epidemiology of infectious diseases. Conclusions S3QL was found to provide a convenient mechanism to represent context for interoperation between public and private datasets hosted at biomedical research institutions and linked data formalisms.

  11. Frequency domain design of gain scheduling control for large wind systems in full-load region

    International Nuclear Information System (INIS)

    Highlights: • A large wind energy system, operating under full-load regime, is considered. • According to its particularities in frequency domain, control law design is provided. • These particularities are influenced by the interactions of wind–tower–blade ensemble. • Control low, within gain scheduling strategy, is achieved imposing stability reserve. • Supplementary a criterion, aimed at reducing mechanical loads, is imposed. - Abstract: The paper presents the issue of power control law synthesis, in the case of a large wind system that operates under full-load regime, based on dynamic properties details in frequency domain. Solving this problem involves two phases: the establishment of a linearized model as faithfully as possible in various operating points of the full-load region, and synthesis of the power controller, considered with classic structure, taking into account frequency particularities of the obtained linearized model. Obtained linear model of the controlled process is of order 16 and encloses subsystems for tower fore-aft oscillations damping, and for drive-train torsion oscillations damping. The designed controller contains a PI component and a lag compensator for dynamic correction at high frequencies. It is known that the main features of wind system dynamics generated by the interaction of wind–tower–blade ensemble cause a gap in the gain characteristic of the model and complex conjugate zeros, which can move between right and left half-planes, depending on the average wind speed value. Consequently, for control law synthesis an interactive frequency solution is adopted. This is “transparent” in relation to particularities induced by wind–tower–blade interaction. This solution allows evaluation of the extent to which control law is affected by the subsystem for tower oscillations damping. Given the strong dependence between the model and the mean wind speed value, a gain scheduling control law is designed. At

  12. Controlled source time-domain electromagnetic methods for seafloor electric conductivity mapping

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Theoretical studies of some controlled-source electromagnetic methods, especially the horizontal coaxial magnetic dipole-dipole and horizontal collinear electric dipole-dipole electromagnetic methods, which are capable of accuratelymeasuring the relatively low conductivity of the seafioor were reviewed. Marine electromagnetic instrumentations, espe-cially the time-domain horizontal magnetic dipole-dipole system and horizontal electric dipole-dipole system which havebeen designed and constructed in the Geophysics Division of the University of Toronto, were provided with applications togootechnical studies on the shelf and deep ocean surveys near the mid-ocean ridges

  13. A Domain-specific Framework for Automated Construction and Verification of Railway Control Systems

    DEFF Research Database (Denmark)

    Haxthausen, Anne Elisabeth

    2009-01-01

    elaborate safety mechanisms in order to keep the risk at the same low level that has been established for European railways until today. The challenge is further increased by the demand for shorter time-to-market periods and higher competition among suppliers of the railway domain; both factors resulting in...... a demand for a higher degree of automation for the development verification, validation and test phases of projects, without impairing the thoroughness of safety-related quality measures and certification activities. Motivated by these considerations, this presentation describes an approach for...... automated construction and verification of railway control systems....

  14. A Multi-Domain Access Control Infrastructure Based on Diameter and EAP

    Science.gov (United States)

    Ben Ayed, Souheil; Teraoka, Fumio

    The evolution of Internet, the growth of Internet users and the new enabled technological capabilities place new requirements to form the Future Internet. Many features improvements and challenges were imposed to build a better Internet, including securing roaming of data and services over multiple administrative domains. In this research, we propose a multi-domain access control infrastructure to authenticate and authorize roaming users through the use of the Diameter protocol and EAP. The Diameter Protocol is a AAA protocol that solves the problems of previous AAA protocols such as RADIUS. The Diameter EAP Application is one of Diameter applications that extends the Diameter Base Protocol to support authentication using EAP. The contributions in this paper are: 1) first implementation of Diameter EAP Application, called DiamEAP, capable of practical authentication and authorization services in a multi-domain environment, 2) extensibility design capable of adding any new EAP methods, as loadable plugins, without modifying the main part, and 3) provision of EAP-TLS plugin as one of the most secure EAP methods. DiamEAP Server basic performances were evaluated and tested in a real multi-domain environment where 200 users attempted to access network using the EAP-TLS method during an event of 4 days. As evaluation results, the processing time of DiamEAP using the EAP-TLS plugin for authentication of 10 requests is about 20ms while that for 400 requests/second is about 1.9 second. Evaluation and operation results show that DiamEAP is scalable and stable with the ability to handle more than 6 hundreds of authentication requests per second without any crashes. DiamEAP is supported by the AAA working group of the WIDE Project.

  15. A PAS Domain-Containing Regulator Controls Flagella-Flagella Interactions in Campylobacter jejuni

    Directory of Open Access Journals (Sweden)

    Mark eReuter

    2015-07-01

    Full Text Available The bipolar flagella of the foodborne bacterial pathogen Campylobacter jejuni confermotility, which is essential for virulence. The flagella of C. jejuni are posttranslationallymodified, but how this process is controlled is not well understood. Inthis work, we have identified a novel PAS-domain containing regulatory system, whichmodulates flagella-flagella interactions in C. jejuni. Inactivation of the cj1387c gene,encoding a YheO-like PAS6 domain linked to a helix-turn-helix domain, resulted in thegeneration of a tightly associated 'cell-train' morphotype, where up to four cells wereconnected by their flagella. The morphotype was fully motile, resistant to vortexing,accompanied by increased autoagglutination, and was not observed in aflagellated cells.The Δcj1387c mutant displayed increased expression of the adjacent Cj1388 protein,which comprises of a single endoribonuclease L-PSP domain. Comparative genomicsshowed that cj1387c (yheO orthologs in bacterial genomes are commonly linked to anadjacent cj1388 ortholog, with some bacteria, including C. jejuni, containing anothercj1388-like gene (cj0327. Inactivation of the cj1388 and cj0327 genes resulted indecreased autoagglutination in Tween-20-supplemented media. The Δcj1388 andΔcj0327 mutants were also attenuated in a Galleria larvae-based infection model.Finally, substituting the sole cysteine in Cj1388 for serine prevented Cj1388dimerisation in non-reducing conditions, and resulted in decreased autoagglutination inthe presence of Tween-20. We hypothesize that Cj1388 and Cj0327 modulate posttranslationalmodification of the flagella through yet unidentified mechanisms, andpropose naming Cj1387 the Campylobacter Flagella Interaction Regulator CfiR, andthe Cj1388 and Cj0327 protein as CfiP and CfiQ, respectively.

  16. Type III apical transportation of root canal

    Directory of Open Access Journals (Sweden)

    Shiv P Mantri

    2012-01-01

    Full Text Available Procedural accidents leading to complications such as canal transportation have been ascribed to inapt cleaning and shaping concepts. Canal transportation is an undesirable deviation from the natural canal path. Herewith a case of apical transportation of root canal resulting in endodontic retreatment failure and its management is presented. A healthy 21-year-old young male presented discomfort and swelling associated with painful endodontically retreated maxillary incisor. Radiograph revealed periradicular radiolucency involving underfilled 11 and overfilled 12. Insufficiently obturated 11 exhibited apical transportation of canal. This type III transportation was treated by periradicular surgery and repair using white mineral trioxide aggregate (MTA. Comfortable asymptomatic patient presented uneventful healing at third and fourth month recall visits. A decrease in the size of radiolucency in radiograph supported the clinical finding. In the present case, MTA is useful in repairing the transportation defect. The result of these procedures is predictable and successful.

  17. Inflammatory Myofibroblastic Tumor Mimicking Apical Periodontitis.

    Science.gov (United States)

    Adachi, Makoto; Kiho, Kazuki; Sekine, Genta; Ohta, Takahisa; Matsubara, Makoto; Yoshida, Takakazu; Katsumata, Akitoshi; Tanuma, Jun-ichi; Sumitomo, Shinichiro

    2015-12-01

    Inflammatory myofibroblastic tumors (IMTs) are rare. IMTs of the head and neck occur in all age groups, from neonates to old age, with the highest incidence occurring in childhood and early adulthood. An IMT has been defined as a histologically distinctive lesion of uncertain behavior. This article describes an unusual case of IMT mimicking apical periodontitis in the mandible of a 42-year-old man. At first presentation, the patient showed spontaneous pain and percussion pain at teeth #28 to 30, which continued after initial endodontic treatment. Panoramic radiography revealed a radiolucent lesion at the site. Cone-beam computed tomographic imaging showed osteolytic lesions, suggesting an aggressive neoplasm requiring incisional biopsy. Histopathological examination indicated an IMT. The lesion was removed en bloc under general anesthesia, and the patient manifested no clinical evidence of recurrence for 24 months. Lesions of nonendodontic origin should be included in the differential diagnosis of apical periodontitis. Every available diagnostic tool should be used to confirm the diagnosis. Cone-beam computed tomographic imaging is very helpful for differential diagnosis in IMTs mimicking apical periodontitis. PMID:26602450

  18. Coherent control of magnetization precession in electrically detected time domain ferromagnetic resonance

    Energy Technology Data Exchange (ETDEWEB)

    Wid, O.; Wahler, M.; Homonnay, N.; Richter, T. [Institut für Physik, Martin-Luther-Universität Halle-Wittenberg, D-06099 (Germany); Schmidt, G., E-mail: georg.schmidt@physik.uni-halle.de [Institut für Physik, Martin-Luther-Universität Halle-Wittenberg, D-06099 (Germany); IZM, Martin-Luther-Universität Halle-Wittenberg, D-06099 (Germany)

    2015-11-15

    We demonstrate coherent control of time domain ferromagnetic resonance by all electrical excitation and detection. Using two ultrashort magnetic field steps with variable time delay we control the induction decay in yttrium iron garnet (YIG). By setting suitable delay times between the two steps the precession of the magnetization can either be enhanced or completely stopped. The method allows for a determination of the precession frequency within a few precession periods and with an accuracy much higher than can be achieved using fast fourier transformation. Moreover it holds the promise to massively increase precession amplitudes in pulsed inductive microwave magnetometry (PIMM) using low amplitude finite pulse trains. Our experiments are supported by micromagnetic simulations which nicely confirm the experimental results.

  19. A glycophospholipid membrane anchor acts as an apical targeting signal in polarized epithelial cells

    OpenAIRE

    1989-01-01

    Glycosyl-phosphatidylinositol- (GPI) anchored proteins contain a large extracellular protein domain that is linked to the membrane via a glycosylated form of phosphatidylinositol. We recently reported the polarized apical distribution of all endogenous GPI-anchored proteins in the MDCK cell line (Lisanti, M. P., M. Sargiacomo, L. Graeve, A. R. Saltiel, and E. Rodriguez-Boulan. 1988. Proc. Natl. Acad. Sci. USA. 85:9557-9561). To study the role of this mechanism of membrane anchoring in targeti...

  20. SPT6L Encoding a Putative WG/GW-Repeat Protein Regulates Apical-Basal Polarity of Embryo in Arabidopsis

    Institute of Scientific and Technical Information of China (English)

    Xiao-Lu Gu; Hua Wang; Hai Huang; Xiao-Feng Cui

    2012-01-01

    In eukaryotes,a protein motif consisting of WG/GW repeats,also called the Argonaute (AGO) hook,is thought to be essential for binding AGO proteins to fulfill their functions in RNA-mediated gene silencing.Although a number of WG/GW-containing proteins have been computationally identified in Arabidopsis,their roles in plant growth and development are unknown.Here,we show that the Arabidopsis Suppressor of Ty insertion 6-like (SPT6L) gene,which encodes a protein with C-terminal WG/GW repeats,plays critical roles in embryonic development.SPT6L is evolutionarily conserved only in vascular plants,with varying numbers of C-terminal WG/GW repeats,which are plant-species specific.spt61 mutants formed embryos with an aberrant apical-basal axis,showing insufficient development of the basal domain and embryonic lethality.Expression domains of the class-Ⅲ homeodomain-leucine zipper (HD-ZIP Ⅲ) genes PHABULOSA (PHB) and PHAVOLUTA (PHV) were expanded in the spt61 embryo.In contrast,the PLETHORA1 (PLT1) gene,which acts antagonistically to the HD-ZIP Ⅲ genes in specification of basal fate,was severely down-regulated in the spt61 mutant.Furthermore,the phb phv double mutations partially rescued aberrant basal development in the spt61 background and restored PLT1 expression.Collectively,our results indicate that SPT6L is essential for specification of the apical-basal axis,partly by controlling the HD-ZIP Ⅲ genes in embryos.

  1. Virus-Induced Chaperone-Enriched (VICE domains function as nuclear protein quality control centers during HSV-1 infection.

    Directory of Open Access Journals (Sweden)

    Christine M Livingston

    2009-10-01

    Full Text Available Virus-Induced Chaperone-Enriched (VICE domains form adjacent to nuclear viral replication compartments (RC during the early stages of HSV-1 infection. Between 2 and 3 hours post infection at a MOI of 10, host protein quality control machinery such as molecular chaperones (e.g. Hsc70, the 20S proteasome and ubiquitin are reorganized from a diffuse nuclear distribution pattern to sequestration in VICE domains. The observation that VICE domains contain putative misfolded proteins suggests that they may be similar to nuclear inclusion bodies that form under conditions in which the protein quality control machinery is overwhelmed by the presence of misfolded proteins. The detection of Hsc70 in VICE domains, but not in nuclear inclusion bodies, indicates that Hsc70 is specifically reorganized by HSV-1 infection. We hypothesize that HSV-1 infection induces the formation of nuclear protein quality control centers to remodel or degrade aberrant nuclear proteins that would otherwise interfere with productive infection. Detection of proteolytic activity in VICE domains suggests that substrates may be degraded by the 20S proteasome in VICE domains. FRAP analysis reveals that GFP-Hsc70 is dynamically associated with VICE domains, suggesting a role for Hsc70 in scanning the infected nucleus for misfolded proteins. During 42 degrees C heat shock, Hsc70 is redistributed from VICE domains into RC perhaps to remodel viral replication and regulatory proteins that have become insoluble in these compartments. The experiments presented in this paper suggest that VICE domains are nuclear protein quality control centers that are modified by HSV-1 to promote productive infection.

  2. Management and control applications in Agriculture domain via a Future Internet Business-to-Business platform

    Directory of Open Access Journals (Sweden)

    Sokratis Barmpounakis

    2015-05-01

    Full Text Available The Agriculture business domain, as a vital part of the overall supply chain, is expected to highly evolve in the upcoming years via the developments, which are taking place on the side of the Future Internet. This paper presents a novel Business-to-Business collaboration platform from the agri-food sector perspective, which aims to facilitate the collaboration of numerous stakeholders belonging to associated business domains, in an effective and flexible manner. The contemporary B2B collaboration schemes already place the requirements for swift deployment of cloud applications, capable of both integrating diverse legacy systems, as well as developing in a rapid way new services and systems, which will be able to instantly communicate and provide complete, “farm-to-fork” solutions for farmers, agri-food and logistics service providers, ICT companies, end-product producers, etc. To this end, this conceptual paper describes how these requirements are addressed via the FIspace B2B platform, focusing on the Greenhouse Management & Control scenarios.

  3. Time domain acoustic contrast control implementation of sound zones for low-frequency input signals

    DEFF Research Database (Denmark)

    Schellekens, Daan H. M.; Møller, Martin Bo; Olsen, Martin

    2016-01-01

    Sound zones are two or more regions within a listening space where listeners are provided with personal audio. Acoustic contrast control (ACC) is a sound zoning method that maximizes the average squared sound pressure in one zone constrained to constant pressure in other zones. State-of-the-art t......Sound zones are two or more regions within a listening space where listeners are provided with personal audio. Acoustic contrast control (ACC) is a sound zoning method that maximizes the average squared sound pressure in one zone constrained to constant pressure in other zones. State......-of-the-art time domain broadband acoustic contrast control (BACC) methods are designed for anechoic environments. These methods are not able to realize a flat frequency response in a limited frequency range within a reverberant environment. Sound field control in a limited frequency range is a requirement...... to accommodate the effective working range of the loudspeakers. In this paper, a new BACC method is proposed which results in an implementation realizing a flat frequency response in the target zone. This method is applied in a bandlimited low-frequency scenario where the loudspeaker layout surrounds two...

  4. Frecuencia de periodontitis apical en tratamientos endodónticos de pregrado Frequency of apical periodontitis in endodontic treatment in undergraduate

    Directory of Open Access Journals (Sweden)

    P León

    2011-12-01

    Full Text Available La periodontitis apical es una enfermedad de los tejidos periapicales de etiología bacteriana. Su tratamiento requiere erradicar los microorganismos del conducto radicular y obturarlo para lograr la reparación posterior. El objetivo de éste trabajo fue determinar la frecuencia de periodontitis apical en la población que asiste a la clínica de Endodoncia de la Facultad de Odontología de la Universidad de Chile y su relación con diferentes variables: diagnóstico específico, edad, sexo, agudas vs. crónicas, éxito/fracaso del tratamiento y rehabilitación post-tratamiento. Se recolectó información de 292 dientes de pacientes tratados en dicha clínica, analizándose la información de aquellos con dientes diagnosticados con algún tipo de periodontitis apical clasificándolo según la nueva nomenclatura de la asociación de endodoncia americana. La frecuencia de periodontitis apical fue de un 36.7% (92 pacientes, de los cuales un 77.8% presentaron patologías de tipo crónicas. Un 75% de los pacientes pertenecieron al sexo femenino y la 5ta década representó un 34.8% de los pacientes. El 100% de los pacientes que acudieron a control presentó éxito en sus tratamientos según variables clínico-radiográficas, mientras que la restauración más frecuente post-tratamiento fue la resina compuesta (52.4%. Dado el pequeño número de pacientes que concurrieron a la citación de control para determinar el éxito del tratamiento, esta variable debe ser considerada como preliminar. Nuestros resultados mostraron que la condición mas frecuente fue la periodontitis apical de tipo crónica, afectando más a mujeres y a la 5ta década.Apical periodontitis is a microbially induced inflammatory disease of the periapical tissues. Its treatment requires eliminating microorganism from root canal and sealing it properly to induce further tissue repair. The aim of this study was to determine the frequency of apical periodontitis and its distribution by

  5. Conformational control of the binding of the transactivation domain of the MLL protein and c-Myb to the KIX domain of CREB.

    Directory of Open Access Journals (Sweden)

    Elif Nihal Korkmaz

    Full Text Available The KIX domain of CBP is a transcriptional coactivator. Concomitant binding to the activation domain of proto-oncogene protein c-Myb and the transactivation domain of the trithorax group protein mixed lineage leukemia (MLL transcription factor lead to the biologically active ternary MLL∶KIX∶c-Myb complex which plays a role in Pol II-mediated transcription. The binding of the activation domain of MLL to KIX enhances c-Myb binding. Here we carried out molecular dynamics (MD simulations for the MLL∶KIX∶c-Myb ternary complex, its binary components and KIX with the goal of providing a mechanistic explanation for the experimental observations. The dynamic behavior revealed that the MLL binding site is allosterically coupled to the c-Myb binding site. MLL binding redistributes the conformational ensemble of KIX, leading to higher populations of states which favor c-Myb binding. The key element in the allosteric communication pathways is the KIX loop, which acts as a control mechanism to enhance subsequent binding events. We tested this conclusion by in silico mutations of loop residues in the KIX∶MLL complex and by comparing wild type and mutant dynamics through MD simulations. The loop assumed MLL binding conformation similar to that observed in the KIX∶c-Myb state which disfavors the allosteric network. The coupling with c-Myb binding site faded, abolishing the positive cooperativity observed in the presence of MLL. Our major conclusion is that by eliciting a loop-mediated allosteric switch between the different states following the binding events, transcriptional activation can be regulated. The KIX system presents an example how nature makes use of conformational control in higher level regulation of transcriptional activity and thus cellular events.

  6. Apical dominance in Alstroemeria cultured in vitro

    OpenAIRE

    Pumisutapon, P.; Visser, R. G. F.; Klerk, de, L.A.

    2009-01-01

    Apical dominance in Alstroemeria is studied to develop an improved propagation protocol for this crop. Four types of explants were prepared: an intact rhizome with two intact shoots (+R+2S), an intact rhizome with two decapitated shoots (+R-2S), a decapitated rhizome with two intact shoots (-R+2S), and a decapitated rhizome with two decapitated shoots (-R-2S). The explants were cultivated on solid MS medium with 9 µM 6-benzylaminopurine (BAP). -R-2S explants showed the highest and +R+2S the l...

  7. Multimodality imaging in apical hypertrophic cardiomyopathy

    Institute of Scientific and Technical Information of China (English)

    Rosario; Parisi; Francesca; Mirabella; Gioel; Gabrio; Secco; Rossella; Fattori

    2014-01-01

    Apical hypertrophic cardiomyopathy(AHCM) is a relatively rare morphologic variant of HCM in which the hypertrophy of myocardium is localized to the left ventricular apex. Symptoms of AHCM might vary from none to others mimic coronary artery disease including acute coronary syndrome, thus resulting in inappropriate hospitalization. Transthoracic echocardiography is the firstline imaging technique for the diagnosis of hypertrophic cardiomyopathies. However, when the hypertrophy of the myocardium is localized in the ventricular apex might results in missed diagnosis. Aim of this paper is to review the different imaging techniques used for the diagnosis of AHCM and their role in the detection and comprehension of this uncommon disease.

  8. Lexical-semantic Mapping between Chinese and English Controlled Vocabularies in the Domain of Chinese Art

    Directory of Open Access Journals (Sweden)

    Shu-Jiun Chen

    2015-12-01

    Full Text Available This study conducts a lexical-semantic mapping between the Chinese controlled vocabulary developed by the National Palace Museum (NPM-CV in Taiwan and an English controlled vocabulary, the Art & Architecture Thesaurus (AAT developed by the Getty Research Institute in the U.S. that is primarily based on Western art. The research question is: In mapping a Chinese controlled vocabulary in Chinese art to a Western-centered art thesaurus, what types of relationships can be identified and what are the issues in mapping? The study’s main findings reveal that only one-third of the NPM-CV terms can be mapped as “exact equivalence” to AAT terms and three-fifths of the NPMCV terms have hierarchical relationships (narrower to broader with some AAT terms. Clearly, using AAT alone to index Chinese art collections will lead to insufficient indexing specificity. The study then proposes solutions to improve Chinese-English semantic interoperability for multilingual knowledge organization systems in the domain of Chinese art. [Article content in Chinese

  9. 多域环境下的分布式RBAC模型%A distributed role-based access control model for multi-domain environments

    Institute of Scientific and Technical Information of China (English)

    洪帆; 朱贤; 邢光林

    2006-01-01

    Access control in multi-domain environments is an important question in building coalition between domains. Based on the RBAC access control model and the concepts of secure domain,the role delegation and role mapping are proposed, which support the third-party authorization. A distributed RBAC model is then presented. Finally implementation issues are discussed.

  10. Apical dominance and growth in vitro of Alstroemeria

    OpenAIRE

    Pumisutapon, P.

    2012-01-01

    In Alstroemeria, micropropagation is achieved by axillary bud outgrowth. However, the multiplication rate is rather low (1.2–2.0 per cycle of 4 weeks) due to strong apical dominance. Even though several factors (i.e. culture media, growth regulators, and environmental conditions) have been studied, no significant improvements have been achieved. Basic research on apical dominance mechanism in Alstroemeria is therefore required. This may enhance the understanding how apical dominance con...

  11. Domain morphology controlled crystal habits in PbTiO{sub 3} nanocrystals

    Energy Technology Data Exchange (ETDEWEB)

    Dudhe, C.M., E-mail: chandraguptadudhe@gmail.com; Khambadkar, S.J.

    2015-11-05

    Various crystal habits and associated domain structures in PbTiO{sub 3} nanocrystals synthesized by a modified sol–gel method have been studied. Structural and morphological characterizations of synthesized nanoparticles have been done by X-ray diffraction (XRD) and transmission electron microscopy (TEM). It was found from the -z coordinates of O{sub 1} and O{sub 2} that the Ti–O{sub 6} octahedra were distorted slightly, favorable for the ferroelectric nature. TEM images show butterfly like, plate like, irregular sphere like and oval-shaped habits of the nanocrystals. 90° and 180° domain structures in these crystal habits were explored from their morphologies and appearance in the field of views. The mutual association between the crystal habit and the direction spontaneous polarization P{sub s} due to domain structures was explored. Domain wall energies of 90° and 180° domains were also estimated from the kinetic process of domain nucleation. - Highlights: • Various crystal habits of PbTiO{sub 3} nanoparticles were examined by TEM. • 90° and 180° domains were explored in the nanocrystal. • Crystal habits and domain structures were correlated. • Domain wall energies were estimated.

  12. Neurons derive from the more apical daughter in asymmetric divisions in the zebrafish neural tube.

    Science.gov (United States)

    Alexandre, Paula; Reugels, Alexander M; Barker, David; Blanc, Eric; Clarke, Jonathan D W

    2010-06-01

    In the developing CNS, asymmetric cell division is critical for maintaining the balanced production of differentiating neurons while renewing the population of neural progenitors. In invertebrates, this process depends on asymmetric inheritance of fate determinants during progenitor divisions. A similar mechanism is widely believed to underlie asymmetrically fated divisions in vertebrates, but compelling evidence for this is missing. We used live imaging of individual progenitors in the intact zebrafish embryo CNS to test this hypothesis. We found that asymmetric inheritance of a subcellular domain is strongly correlated with asymmetric daughter fates and our results reveal an unexpected feature of this process. The daughter cell destined to become a neuron was derived from the more apical of the two daughters, whereas the more basal daughter inherited the basal process and replenished the apical progenitor pool.

  13. APICAL TUBERCULOSIS PRESENTING AS PANCOAST TUMOR

    Directory of Open Access Journals (Sweden)

    Praveen

    2014-07-01

    Full Text Available A 73-year-old woman presented with pain in her right shoulder radiating to the right scapula and a tingling sensation of the right arm with involvement of the fourth and fifth finger. Chest x ray showed a well-defined mass in right apical area of lung. HRCT chest showed a well-defined mass in right upper zone in apex destroying the upper 2 ribs. Clinically the diagnosis of Pancoast tumor of the right lung was made. Computed tomographic guided fine needle aspiration cytology was done and it was inconclusive. So gun biopsy was done under ultrasound guidance. The histologic and microbiologic examinations established the diagnosis of tuberculosis (TB.

  14. Apical-dominant particle swarm optimization

    Institute of Scientific and Technical Information of China (English)

    Zhihua Cui; Xingjuan Cai; Jianchao Zeng; Guoji Sun

    2008-01-01

    Particle swarm optimization (PSO) is a new stochastic population-based search methodology by simulating the animal social behaviors such as birds flocking and fish schooling.Many improvements have been proposed within the framework of this biological assumption.However,in this paper,the search pattern of PSO is used to model the branch growth process of natural plants.It provides a different poten-tial manner from artificial plant.To illustrate the effectiveness of this new model,apical dominance phenomenon is introduced to construct a novel variant by emphasizing the influence of the phototaxis.In this improvement,the population is divided into three different kinds of buds associated with their performances.Furthermore,a mutation strategy is applied to enhance the ability escaping from a local optimum.Sim-ulation results demonstrate good performance of the new method when solving high-dimensional multi-modal problems.

  15. Myb-domain protein Teb1 controls histone levels and centromere assembly in fission yeast.

    Science.gov (United States)

    Valente, Luis P; Dehé, Pierre-Marie; Klutstein, Michael; Aligianni, Sofia; Watt, Stephen; Bähler, Jürg; Cooper, Julia Promisel

    2013-02-01

    The TTAGGG motif is common to two seemingly unrelated dimensions of chromatin function-the vertebrate telomere repeat and the promoter regions of many Schizosaccharomyces pombe genes, including all of those encoding canonical histones. The essential S. pombe protein Teb1 contains two Myb-like DNA binding domains related to those found in telomere proteins and binds the human telomere repeat sequence TTAGGG. Here, we analyse Teb1 binding throughout the genome and the consequences of reduced Teb1 function. Chromatin immunoprecipitation (ChIP)-on-chip analysis reveals robust Teb1 binding at many promoters, notably including all of those controlling canonical histone gene expression. A hypomorphic allele, teb1-1, confers reduced binding and reduced levels of histone transcripts. Prompted by previously suggested connections between histone expression and centromere identity, we examined localization of the centromeric histone H3 variant Cnp1 and found reduced centromeric binding along with reduced centromeric silencing. These data identify Teb1 as a master regulator of histone levels and centromere identity. PMID:23314747

  16. Increased monolayer domain size and patterned growth of tungsten disulfide through controlling surface energy of substrates

    Science.gov (United States)

    Godin, Kyle; Kang, Kyungnam; Fu, Shichen; Yang, Eui-Hyeok

    2016-08-01

    We report a surface energy-controlled low-pressure chemical vapor deposition growth of WS2 monolayers on SiO2 using pre-growth oxygen plasma treatment of substrates, facilitating increased monolayer surface coverage and patterned growth without lithography. Oxygen plasma treatment of the substrate caused an increase in the average domain size of WS2 monolayers by 78%  ±  2% while having a slight reduction in nucleation density, which translates to increased monolayer surface coverage. This substrate effect on growth was exploited to grow patterned WS2 monolayers by patterned plasma treatment on patterned substrates and by patterned source material with resolutions less than 10 µm. Contact angle-based surface energy measurements revealed a dramatic increase in polar surface energy. A growth model was proposed with lowered activation energies for growth and increased surface diffusion length consistent with the range of results observed. WS2 samples grown with and without oxygen plasma were similar high quality monolayers verified through transmission electron microscopy, selected area electron diffraction, atomic force microscopy, Raman, and photoluminescence measurements. This technique enables the production of large-grain size, patterned WS2 without a post-growth lithography process, thereby providing clean surfaces for device applications.

  17. Hormonal networks involved in apical hook development in darkness and their response to light

    Directory of Open Access Journals (Sweden)

    Maria Agustina Mazzella

    2014-02-01

    Full Text Available In darkness, the dicot seedlings produces an apical hook as result of differential cell division and extension at opposite sides of the hypocotyl. This hook protects the apical meristem from mechanical damage during seedling emergence from the soil. In darkness, gibberellins act via the DELLA-PIF (PHYTOCHROME INTERACTING FACTORs pathway, and ethylene acts via the EIN3/EIL1 (ETHYLENE INSENSITIE 3/EIN3 like 1-HLS1 (HOOKLESS 1 pathway to control the asymmetric accumulation of auxin required for apical hook formation and maintenance. These core pathways form a network with multiple points of connection. Light perception by phytochromes and cryptochromes reduces the activity of PIFs and CONSTITUTIVE PHOTOMORPHOGENIC 1 (COP1 --both required for hook formation in darkness--, lowers the levels of gibberellins, and triggers hook opening as a component of the switch between heterotrophic and photoautotrophic development. Apical hook opening is thus a suitable model to study the convergence of endogenous and exogenous signals on the control of cell division and cell growth.

  18. Reversible transient apical ballooning syndrome with coronary lesions

    Institute of Scientific and Technical Information of China (English)

    Yunshan Cao; Min Zhang; Xiang Li; Ping Xie; Lynn Cronin

    2009-01-01

    Transient apical ballooning syndrome(Tako-Tsubo syndrome or ampulla cardiomyopathy) occurs predominantly in women over 60 years of age with a history of recent physical or psychological stress. We present a case of a male patient with reversible transient apical ballooning syndrome with significant coronary lesions and other ECG changes that did not explain the clinical symptoms.

  19. Multidimensional CAT Item Selection Methods for Domain Scores and Composite Scores with Item Exposure Control and Content Constraints

    Science.gov (United States)

    Yao, Lihua

    2014-01-01

    The intent of this research was to find an item selection procedure in the multidimensional computer adaptive testing (CAT) framework that yielded higher precision for both the domain and composite abilities, had a higher usage of the item pool, and controlled the exposure rate. Five multidimensional CAT item selection procedures (minimum angle;…

  20. Overlapping Domain Decomposition Methods for Elliptic Quasi-Variational Inequalities Related to Impulse Control Problem with Mixed Boundary Conditions

    Indian Academy of Sciences (India)

    Mohamed Haiour; Salah Boulaaras

    2011-11-01

    In this paper we provide a maximum norm analysis of an overlapping Schwarz method on non-matching grids for quasi-variational inequalities related to impulse control problem with mixed boundary conditions. We provide that the discretization on every sub-domain converges in uniform norm. Furthermore, a result of approximation in uniform norm is given.

  1. Discrete-time domain two-degree-of-freedom control design for integrating and unstable processes with time delay.

    Science.gov (United States)

    Wang, Dong; Liu, Tao; Sun, Ximing; Zhong, Chongquan

    2016-07-01

    A discrete-time domain two-degree-of-freedom (2DOF) design method is proposed for integrating and unstable processes with time delay. Based on a 2DOF control structure recently developed, a controller is analytically designed in terms of the H2 optimal control performance specification for the set-point tracking, and another controller is derived by proposing the desired closed-loop transfer function for load disturbance rejection. Both controllers can be tuned relatively independent to realize control optimization. Analytical expression of the set-point response is given for quantitatively tuning the single adjustable parameter in the set-point tracking controller. At the meantime, sufficient and necessary conditions for holding robust stability of the closed-loop control system are established for tuning another adjustable parameter in the disturbance rejection controller, along with numerical tuning guidelines. Illustrative examples from the literature are used to demonstrate the effectiveness of the proposed method.

  2. Multiple domains of Stardust differentially mediate localisation of the Crumbs-Stardust complex during photoreceptor development in Drosophila.

    Science.gov (United States)

    Bulgakova, Natalia A; Kempkens, Ozlem; Knust, Elisabeth

    2008-06-15

    Drosophila Stardust (Sdt), a member of the MAGUK family of scaffolding proteins, is a constituent of the evolutionarily conserved Crumbs-Stardust (Crb-Sdt) complex that controls epithelial cell polarity in the embryo and morphogenesis of photoreceptor cells. Although apical localisation is a hallmark of the complex in all cell types and in all organisms analysed, only little is known about how individual components are targeted to the apical membrane. We have performed a structure-function analysis of Sdt by constructing transgenic flies that express altered forms of Sdt to determine the roles of individual domains for localisation and function in photoreceptor cells. The results corroborate the observation that the organisation of the Crb-Sdt complex is differentially regulated in pupal and adult photoreceptors. In pupal photoreceptors, only the PDZ domain of Sdt - the binding site of Crb - is required for apical targeting. In adult photoreceptors, by contrast, targeting of Sdt to the stalk membrane, a distinct compartment of the apical membrane between the rhabdomere and the zonula adherens, depends on several domains, and seems to be a two-step process. The N-terminus, including the two ECR domains and a divergent N-terminal L27 domain that binds the multi-PDZ domain protein PATJ in vitro, is necessary for targeting the protein to the apical pole of the cell. The PDZ-, the SH3- and the GUK-domains are required to restrict the protein to the stalk membrane. Drosophila PATJ or Drosophila Lin-7 are stabilised whenever a Sdt variant that contains the respective binding site is present, independently of where the variant is localised. By contrast, only full-length Sdt, confined to the stalk membrane, stabilises and localises Crb, although only in reduced amounts. The amount of Crumbs recruited to the stalk membrane correlates with its length. Our results highlight the importance of the different Sdt domains and point to a more intricate regulation of the Crb

  3. Engineered peptides with enzymatically cleavable domains for controlling the release of model protein drug from "soft" nanoparticles.

    Science.gov (United States)

    Singh, Harsh Deep; Bushnak, Ibraheem; Unsworth, Larry D

    2012-02-01

    Matrix metalloproteinase-2 (MMP-2) is an endopeptidase that has been shown to be present in high concentrations during most tissue remodeling events, including disease states like active tumor sites, thus making it an attractive molecule for use in effecting local delivery of therapeutic molecules. Moreover, the use of non-toxic and biodegradable nanoparticles for controlled drug delivery is highly sought after. To this end, bovine serum albumin (BSA) nanoparticles (NPs) were stabilized with coatings formed using domains of varying sensitivity to MMP-2, viz. K6GPQG/IASQK6 and K6HPVG/LLARK6, lysine residues being used to facilitate peptide immobilization to the BSA NPs via electrostatic interactions, and peptide domains that have a high (HPVG/LLAR) and low (GPQG/IASQ) MMP-2 cleavage rate. The MMP-2-induced cleavage rates of these two domains (the position of action being noted with a "/") have differing kinetics that can be used to provide a novel mechanism for facilitating the controlled release of molecules where local concentrations of MMP-2 are high. It was found that both surface concentration and cleavage domain type influenced the release of the model drug (BSA) from these NPs. This stratagem may provide a novel pathway for developing multi-functional coatings for controlling the local delivery of therapeutics at sites where the presence of various enzymes exist as a function of tissue state. PMID:22062019

  4. The antimicrobial effect of apical box versus apical cone preparation using iodine potassium iodide as root canal dressing

    DEFF Research Database (Denmark)

    Markvart, Merete; Dahlén, Gunnar; Reit, Claes-Erik;

    2013-01-01

    Abstract Purpose. The purpose was to study the reduction of intra-canal microflora in premolars with apical periodontitis instrumented with either apical box or apical cone preparation and to provide measurements of intervention effects to allow proper power calculation in future clinical trials....... Methods. Twenty-four patients were centrally randomized to apical box preparation (size #60) or cone preparation (apical size #25). The groups were comparable regarding the presence of primary caries and type of coronal restoration. In the course of canal preparation each tooth was irrigated with 2.5% Na......OCl (12 ml). Lastly, the canals were filled with 17% EDTA (2 × 30 s) and 5% iodine potassium iodide (IKI) for 10 min. The canals were sampled for micro-organisms on four occasions: before instrumentation, after instrumentation, after application of IKI dressing and at the beginning of the second...

  5. Responses of Metabolites in Soybean Shoot Apices to Changing Atmospheric Carbon Dioxide Concentrations

    Directory of Open Access Journals (Sweden)

    Richard Sicher

    2012-01-01

    Full Text Available Soybean seedlings were grown in controlled environment chambers with CO2 partial pressures of 38 (ambient and 72 (elevated Pa. Five or six shoot apices were harvested from individual 21- to 24-day-old plants. Metabolites were analyzed by gas chromatography and, out of 21 compounds, only sucrose and fructose increased in response to CO2 enrichment. One unidentified metabolite, Unk-21.03 decreased up to 80% in soybean apices in response to elevated CO2. Levels of Unk-21.03 decreased progressively when atmospheric CO2 partial pressures were increased from 26 to 100 Pa. Reciprocal transfer experiments showed that Unk-21.03, and sucrose in soybean apices were altered slowly over several days to changes in atmospheric CO2 partial pressures. The mass spectrum of Unk-21.03 indicated that this compound likely contained both an amino and carboxyl group and was structurally related to serine and aspartate. Our findings suggested that CO2 enrichment altered a small number of specific metabolites in soybean apices. This could be an important step in understanding how plant growth and development are affected by carbon dioxide enrichment.

  6. Effect of master apical file size and taper on irrigation and cleaning of the apical third of curved canals.

    Directory of Open Access Journals (Sweden)

    Nahid Mohammadzadeh Akhlaghi

    2014-04-01

    Full Text Available Canal preparation generates a substantial amount of debris and smear layer (SL. The size and taper of the Master Apical File (MAF affects on penetration of irrigants and subsequently canal cleaning efficacy. The aim of this study was to evaluate the effect of MAF size and taper on penetration of irrigants to the apical third of curved mesiobuccal (MB canals of mandibular first molars.Eighty-nine human mandibular first molars were divided into one control group (n=5 without rotary instrumentation and 6 experimental groups (n=14 each that were prepared with the following RaCe rotary files as MAF: 25.04 (group1, 25.06 (group 2, 30.04 (group 3, 30.06 (group 4, 35.04 (group 5 and 35.06 (group 6. All the experimental groups were rinsed with 2 ml of 17 % EDTA followed by 2 ml of 5.25% NaOCl. Debridement of the MB canals was evaluated using scanning electron microscope (SEM. The data were statistically analyzed using Kruskal-Wallis and Mann-Whitney U tests (P<0.05.Group 6 (MAF=35.06 showed 100% acceptable debridement. This rate was 92.9% for MAF=35.04. In group 4 (MAF=30.06 smear layer (SL was removed in the three-forth of the samples and debris was removed in 92.9% of them. Acceptable debridement was not achieved in most samples of groups 1 and 2 (25.04 and 25.06, respectively and the mentioned two groups had statistically significant difference in this respect with the other groups (P<0.05.Based on this study, 30.06 may be considered as the minimum MAF size for acceptable debridement.

  7. Advantages and limitations of the Five Domains model for assessing welfare impacts associated with vertebrate pest control.

    Science.gov (United States)

    Beausoleil, N J; Mellor, D J

    2015-01-01

    Many pest control activities have the potential to impact negatively on the welfare of animals, and animal welfare is an important consideration in the development, implementation and evaluation of ethically defensible vertebrate pest control. Thus, reliable and accurate methods for assessing welfare impacts are required. The Five Domains model provides a systematic method for identifying potential or actual welfare impacts associated with an event or situation in four physical or functional domains (nutrition, environment, health or functional status, behaviour) and one mental domain (overall mental or affective state). Here we evaluate the advantages and limitations of the Five Domains model for this purpose and illustrate them using specific examples from a recent assessment of the welfare impacts of poisons used to lethally control possums in New Zealand. The model has a number of advantages which include the following: the systematic identification of a wide range of impacts associated with a variety of control tools; the production of relative rankings of tools in terms of their welfare impacts; the easy incorporation of new information into assessments; and the highlighting of additional information needed. For example, a recent analysis of sodium fluoroacetate (1080) poisoning in possums revealed the need for more information on the period from the onset of clinical signs to the point at which consciousness is lost, as well as on the level of consciousness during or after the occurrence of muscle spasms and seizures. The model is also valuable because it clearly separates physical or functional and affective impacts, encourages more comprehensive consideration of negative affective experiences than has occurred in the past, and allows development and evaluation of targeted mitigation strategies. Caution must be used in interpreting and applying the outputs of the model, most importantly because relative rankings or grades are fundamentally qualitative in

  8. Reguladores vegetais na quebra da dominância apical de mamoeiro (Carica papaya L. Plant growth regulators on breaking apical dominance in papaya plants (Carica papaya L.

    Directory of Open Access Journals (Sweden)

    Elizabeth Orika Ono

    2004-08-01

    Full Text Available O trabalho avaliou os efeitos de reguladores vegetais sobre a quebra da dominância apical de mamoeiro (Carica papaya L. cv. Improved Sunrise Solo. A aplicação dos reguladores vegetais foi iniciada quando as plantas tinham seis meses de idade, totalizando três aplicações, a intervalos de sete dias, constando dos seguintes tratamentos: T1- água (testemunha; T2- GA3 250 mg L-1; T3- GA3 500 mg L-1; T4- benziladenina (BA 250 mg L-1; T5- BA 500 mg L-1; T6- GA3 125 mg L-1 + BA 125 mg L-1; T7- GA3 250 mg L-1 + BA 250 mg L-1. Esses tratamentos foram acompanhados da remoção ou não da gema apical. Os resultados mostraram que plantas tratadas com GA3 + BA a 125 e 250 mg L-1, com e sem a remoção da gema apical, apresentaram maior número de brotações que a testemunha, a qual não apresentou nenhuma brotação das gemas laterais.The objective of this work was to study the effects of gibberelin and cytokinin on breaking apical dominance and axillary buds growth of the Carica papaya L. Papaya plants sprayed three times within a period of 7 days, with the following treatments: T1- water (control, T2- GA3 250 mg L-1, T3- GA3 500 mg L-1, T4- benzyladenine (BA 250 mg L-1, T5- BA 500 mg L-1, T6- GA3 125 mg L-1 + BA 125 mg L-1, T7- GA3 250 mg L-1 + BA 250 mg L-1. The treatments were carried out with or without removal of the apical buds. After 36 days of the last plant growth regulators application was observed lateral bud numbers, lateral buds length and lateral buds diameter. The results showed that there were a higher number of shoots in plants treated with GA3 at 125 mg L-1 + BA at 125 mg L-1 and GA3 at 250mg L-1 + BA at 250 mg L-1. The removal of the apical bud helped the sprouting of the papaya plants.

  9. ELKS controls the pool of readily releasable vesicles at excitatory synapses through its N-terminal coiled-coil domains.

    Science.gov (United States)

    Held, Richard G; Liu, Changliang; Kaeser, Pascal S

    2016-06-02

    In a presynaptic nerve terminal, synaptic strength is determined by the pool of readily releasable vesicles (RRP) and the probability of release (P) of each RRP vesicle. These parameters are controlled at the active zone and vary across synapses, but how such synapse specific control is achieved is not understood. ELKS proteins are enriched at vertebrate active zones and enhance P at inhibitory hippocampal synapses, but ELKS functions at excitatory synapses are not known. Studying conditional knockout mice for ELKS, we find that ELKS enhances the RRP at excitatory synapses without affecting P. Surprisingly, ELKS C-terminal sequences, which interact with RIM, are dispensable for RRP enhancement. Instead, the N-terminal ELKS coiled-coil domains that bind to Liprin-α and Bassoon are necessary to control RRP. Thus, ELKS removal has differential, synapse-specific effects on RRP and P, and our findings establish important roles for ELKS N-terminal domains in synaptic vesicle priming.

  10. Maxillary first premolars: I. Morphology of the apical constriction

    Institute of Scientific and Technical Information of China (English)

    Daming Wu; Younong Wu; Ming Hu

    2009-01-01

    Objective: To investigated the apical constriction morphology of maxillary first premolars in the Chinese population. Methods: Eighty recently extracted human maxillary first premolars from a native Chinese population were used. The number and shape of apical constrictions were recorded under a dental operating microscope (DOM) at 12.5X2.5 magnification. After access preparation, a new K-file was inserted into the canal until the tip of the file was just seen at the apical constriction under the DOM. The teeth with files in the canals were X-rayed from a mesiodistal direction using a direct digital radiography (DDR) system, and the distance between the file tip and the center of radiographic apex was directly measured from the computer screen using DDR measurement software. Results: The percentage of teeth with an apical constriction was 78.5% (102/130). The most common apical constriction shapes were oval (55.9%) and round (35.3%). The mean distance between the apical constriction and the anatomical tip of the root was 0.61 mm, and 84.3% (86/102) were within 1 mm. Conclusion: The most common shape of an apical constriction was oval or round, and the distance to the apex was mostly within 1 mm, indicating that root canal therapy should stop 1 mm from the radiographic apex.

  11. Par1b induces asymmetric inheritance of plasma membrane domains via LGN-dependent mitotic spindle orientation in proliferating hepatocytes

    NARCIS (Netherlands)

    Slim, Christiaan L; Lázaro-Diéguez, Francisco; Bijlard, Marjolein; Toussaint, Mathilda J M; de Bruin, Alain; Du, Quansheng; Müsch, Anne; van Ijzendoorn, Sven C D

    2013-01-01

    The development and maintenance of polarized epithelial tissue requires a tightly controlled orientation of mitotic cell division relative to the apical polarity axis. Hepatocytes display a unique polarized architecture. We demonstrate that mitotic hepatocytes asymmetrically segregate their apical p

  12. Coordinated regulation of apical hook development by gibberellins and ethylene in etiolated Arabidopsis seedlings

    Institute of Scientific and Technical Information of China (English)

    Fengying An; Xing Zhang; Ziqiang Zhu; Yusi Ji; Wenrong He; Zhiqiang Jiang; Mingzhe Li; Hongwei Guo

    2012-01-01

    Dark-grown Arabidopsis seedlings develop an apical hook when germinating in soil,which protects the cotyledons and apical meristematic tissues when protruding through the soil.Several hormones are reported to distinctly modulate this process.Previous studies have shown that ethylene and gibberellins (GAs) coordinately regulate the hook development,although the underlying molecular mechanism is largely unknown.Here we showed that GA3 enhanced while paclobutrazol repressed ethylene- and EIN3-overexpression (EIN3ox)-induced hook curvature,and della mutant exhibited exaggerated hook curvature,which required an intact ethylene signaling pathway.Genetic study revealed that GA-enhanced hook development was dependent on HOOKLESS 1 (HLS1),a central regulator mediating the input of the multiple signaling pathways during apical hook development.We further found that GA3 induced (and DELLA proteins repressed) HLS1 expression in an ETHYLENE INSENSITIVE 3/EIN3-LIKE 1 (EIN3/EIL1)-dependent manner,whereby EIN3/EIL1 activated HLS1 transcription by directly binding to its promoter.Additionally,DELLA proteins were found to interact with the DNA-binding domains of EIN3/EIL1 and repress EIN3/EIL1-regulated HLS1 expression.Treatment with naphthylphthalamic acid,a polar auxin transport inhibitor,repressed the constitutively exaggerated hook curvature of EIN3ox line and della mutant,supporting that auxin functions downstream of the ethylene and GA pathways in hook development.Taken together,our results identify EIN3/EIL1 as a new class of DELLA-associated transcription factors and demonstrate that GA promotes apical hook formation in cooperation with ethylene partly by inducing the expression of HLS1 via derepression of EIN3/EIL1 functions.

  13. Cognitive Control of Language Production in Bilinguals Involves a Partly Independent Process within the Domain-General Cognitive Control Network: Evidence from Task-switching and Electrical Brain Activity

    Science.gov (United States)

    Magezi, David A.; Khateb, Asaid; Mouthon, Michael; Spierer, Lucas; Annoni, Jean-Marie

    2012-01-01

    In highly proficient, early bilinguals, behavioural studies of the cost of switching language or task suggest qualitative differences between language control and domain-general cognitive control. By contrast, several neuroimaging studies have shown an overlap of the brain areas involved in language control and domain-general cognitive control.…

  14. Orientation control and domain structure analysis of {100}-oriented epitaxial ferroelectric orthorhombic HfO2-based thin films

    Science.gov (United States)

    Katayama, Kiliha; Shimizu, Takao; Sakata, Osami; Shiraishi, Takahisa; Nakamura, Shogo; Kiguchi, Takanori; Akama, Akihiro; Konno, Toyohiko J.; Uchida, Hiroshi; Funakubo, Hiroshi

    2016-04-01

    Orientation control of {100}-oriented epitaxial orthorhombic 0.07YO1.5-0.93HfO2 films grown by pulsed laser deposition was investigated. To achieve in-plane lattice matching, indium tin oxide (ITO) and yttria-stabilized zirconia (YSZ) were selected as underlying layers. We obtained (100)- and (001)/(010)-oriented films on ITO and YSZ, respectively. Ferroelastic domain formation was confirmed for both films by X-ray diffraction using the superlattice diffraction that appeared only for the orthorhombic symmetry. The formation of ferroelastic domains is believed to be induced by the tetragonal-orthorhombic phase transition upon cooling the films after deposition. The present results demonstrate that the orientation of HfO2-based ferroelectric films can be controlled in the same manner as that of ferroelectric films composed of conventional perovskite-type material such as Pb(Zr, Ti)O3 and BiFeO3.

  15. The BAR Domain Protein PICK1 Controls Vesicle Number and Size in Adrenal Chromaffin Cells

    DEFF Research Database (Denmark)

    da Silva Pinheiro, Paulo César; Jansen, Anna M; de Wit, Heidi;

    2014-01-01

    Protein Interacting with C Kinase 1 (PICK1) is a Bin/Amphiphysin/Rvs (BAR) domain protein involved in AMPA receptor trafficking. Here, we identify a selective role for PICK1 in the biogenesis of large, dense core vesicles (LDCVs) in mouse chromaffin cells. PICK1 colocalized with syntaxin-6, a mar...

  16. Management and control applications in Agriculture domain via a Future Internet Business-to-Business platform

    NARCIS (Netherlands)

    Barmpounakis, S.; Kaloxylos, A.; Groumas, A.; Katsikas, L.; Sarris, V.; Dimtsa, K.; Fournier, F.; Antoniou, E.; Alonistioti, N.; Wolfert, J.

    2015-01-01

    The Agriculture business domain, as a vital part of the overall supply chain, is expected to highly evolve in the upcoming years via the developments, which are taking place on the side of the Future Internet. This paper presents a novel Business-to-Business collaboration platform from the agri-food

  17. Frequency-domain criterion for the chaos synchronization of time-delay power systems under linear feedback control

    Indian Academy of Sciences (India)

    Qian Lin; Xiaofeng Wu; Yun Chen

    2015-12-01

    This paper studies the global synchronization of non-autonomous, time-delay, chaotic power systems via linear state-error feedback control. The frequency domain criterion and the LMI criterion are proposed and applied to design the coupling matrix. Some algebraic criteria via a single-variable linear coupling are derived and formulated in simple algebraic inequalities. The effectiveness of the new criteria is illustrated with numerical examples.

  18. Loss of apical monocilia on collecting duct principal cells impairs ATP secretion across the apical cell surface and ATP-dependent and flow-induced calcium signals.

    Science.gov (United States)

    Hovater, Michael B; Olteanu, Dragos; Hanson, Elizabeth L; Cheng, Nai-Lin; Siroky, Brian; Fintha, Attila; Komlosi, Peter; Liu, Wen; Satlin, Lisa M; Bell, P Darwin; Yoder, Bradley K; Schwiebert, Erik M

    2008-06-01

    mechanical pipetting stimuli trigger release of a common ATP pool. Cilium-competent monolayers responded to flow with an increase in cell Ca(2+) derived from both extracellular and intracellular stores. This flow-induced Ca(2+) signal was less robust in cilium-deficient monolayers. Flow-induced Ca(2+) signals in both preparations were attenuated by extracellular gadolinium and by extracellular apyrase, an ATPase/ADPase. Taken together, these data suggest that apical monocilia are sensory organelles and that their presence in the apical membrane facilitates the formation of a mature ATP secretion apparatus responsive to chemical, osmotic, and mechanical stimuli. The cilium and autocrine ATP signaling appear to work in concert to control cell Ca(2+). Loss of a cilium-dedicated autocrine purinergic signaling system may be a critical underlying etiology for ARPKD and may lead to disinhibition and/or upregulation of multiple sodium (Na(+)) absorptive mechanisms and a resultant severe hypertensive phenotype in ARPKD and, possibly, other diseases. PMID:18368523

  19. Pseudoaneurysm of the left ventricle following apical approach TAVI

    OpenAIRE

    Vanezis Andrew P; Baig Mirza K; Mitchel Ian M; Shajar Matloob; Naik Surendra K; Henderson Robert A; Mathew Thomas

    2011-01-01

    Abstract Symptomatic severe aortic stenosis carries a two year survival of only 50%. However many patients are unsuitable for conventional aortic valve replacement as they are considered too high risk due to significant co-morbidities. Transcatheter Aortic Valve Implantation (TAVI) offers a viable alternative for this high risk patient group, either by the femoral or apical route. This article reports a case of a pseudoaneurysm of the left ventricle following an apical approach TAVI in an eld...

  20. One-step apexification using platelet rich fibrin matrix and mineral trioxide aggregate apical barrier

    Directory of Open Access Journals (Sweden)

    Anisha Kumar

    2014-01-01

    In one-step apexification using MTA, the technical problem encountered is controlling the overfill or underfill of MTA. The use of a matrix material helps to overcome this shortcoming. Platelet rich fibrin (PRF is an immune platelet concentrate, which can be used as a matrix, it also promotes wound healing and repair. This case report presents a case of one step apexification using MTA as an apical barrier and autologous PRF as an internal matrix.

  1. Actin Polymerization Controls the Organization of WASH Domains at the Surface of Endosomes

    OpenAIRE

    Emmanuel Derivery; Emmanuèle Helfer; Véronique Henriot; Alexis Gautreau

    2012-01-01

    Sorting of cargoes in endosomes occurs through their selective enrichment into sorting platforms, where transport intermediates are generated. The WASH complex, which directly binds to lipids, activates the Arp2/3 complex and hence actin polymerization onto such sorting platforms. Here, we analyzed the role of actin polymerization in the physiology of endosomal domains containing WASH using quantitative image analysis. Actin depolymerization is known to enlarge endosomes. Using a novel coloca...

  2. Myb-domain protein Teb1 controls histone levels and centromere assembly in fission yeast

    OpenAIRE

    Valente, Luis P.; Dehé, Pierre-Marie; Klutstein, Michael; Aligianni, Sofia; Watt, Stephen; Bähler, Jürg; Promisel Cooper, Julia

    2013-01-01

    The TTAGGG motif is common to two seemingly unrelated dimensions of chromatin function—the vertebrate telomere repeat and the promoter regions of many Schizosaccharomyces pombe genes, including all of those encoding canonical histones. The essential S. pombe protein Teb1 contains two Myb-like DNA binding domains related to those found in telomere proteins and binds the human telomere repeat sequence TTAGGG. Here, we analyse Teb1 binding throughout the genome and the consequences of reduced Te...

  3. Controlled van der Waals epitaxy of monolayer MoS2 triangular domains on graphene.

    Science.gov (United States)

    Ago, Hiroki; Endo, Hiroko; Solís-Fernández, Pablo; Takizawa, Rina; Ohta, Yujiro; Fujita, Yusuke; Yamamoto, Kazuhiro; Tsuji, Masaharu

    2015-03-11

    Multilayered heterostructures of two-dimensional materials have recently attracted increased interest because of their unique electronic and optical properties. Here, we present chemical vapor deposition (CVD) growth of triangular crystals of monolayer MoS2 on single-crystalline hexagonal graphene domains which are also grown by CVD. We found that MoS2 grows selectively on the graphene domains rather than on the bare supporting SiO2 surface. Reflecting the heteroepitaxy of the growth process, the MoS2 domains grown on graphene present two preferred equivalent orientations. The interaction between the MoS2 and the graphene induced an upshift of the Raman G and 2D bands of the graphene, while significant photoluminescence quenching was observed for the monolayer MoS2. Furthermore, photoinduced current modulation along with an optical memory effect was demonstrated for the MoS2-graphene heterostructure. Our work highlights that heterostructures synthesized by CVD offer an effective interlayer van der Waals interaction which can be developed for large-area multilayer electronic and photonic devices. PMID:25695865

  4. The nucleotide addition cycle of RNA polymerase is controlled by two molecular hinges in the Bridge Helix domain

    Directory of Open Access Journals (Sweden)

    Weinzierl Robert OJ

    2010-10-01

    Full Text Available Abstract Background Cellular RNA polymerases (RNAPs are complex molecular machines that combine catalysis with concerted conformational changes in the active center. Previous work showed that kinking of a hinge region near the C-terminus of the Bridge Helix (BH-HC plays a critical role in controlling the catalytic rate. Results Here, new evidence for the existence of an additional hinge region in the amino-terminal portion of the Bridge Helix domain (BH-HN is presented. The nanomechanical properties of BH-HN emerge as a direct consequence of the highly conserved primary amino acid sequence. Mutations that are predicted to influence its flexibility cause corresponding changes in the rate of the nucleotide addition cycle (NAC. BH-HN displays functional properties that are distinct from BH-HC, suggesting that conformational changes in the Bridge Helix control the NAC via two independent mechanisms. Conclusions The properties of two distinct molecular hinges in the Bridge Helix of RNAP determine the functional contribution of this domain to key stages of the NAC by coordinating conformational changes in surrounding domains.

  5. Domains and domain loss

    DEFF Research Database (Denmark)

    Haberland, Hartmut

    2005-01-01

    The domain concept, originally suggested by Schmidt-Rohr in the 1930’s (as credited in Fishman’s writings in the 1970s), was an attempt to sort out different areas of language use in multilingual societies, which are relevant for language choice. In Fishman’s version, domains were considered...... not described in terms of domains, and recent research e.g. about the multilingual communities in the Danish-German border area seems to confirm this....

  6. Time domain analysis for discrete difference equation on discrete linear system controllable problem's research

    Institute of Scientific and Technical Information of China (English)

    DENG Shu-xian; DING Yu; GE Lei

    2008-01-01

    We usually describle a comparatively more complex control system, especially a multi-inputs and multioutputs system by time domation analytical procedure. While the system's controllability means whether the system is controllable according to certain requirements. It involves not only the system's outputs' controllability but also the controllability of the system's partial or total conditions. The movement is described by difference equation in the linear discrete-time system. Therefore, the problem of controllability of the linear discrete-time system has been converted into a problem of the controllability of discrete-time difference equation. The thesis makes out the determination method of the discrete-time system's controllability and puts forward the sufficient and necessary conditions to determine it's controllability by making a study on the controllability of the linear discrete-time equation.

  7. Effect of apical clearing technique on the treatment outcome of teeth with asymptomatic apical periodontitis: A randomized clinical trial

    Science.gov (United States)

    Mittal, Priya; Logani, Ajay; Shah, Naseem; Pandey, R. M.

    2016-01-01

    Aim: This study aims to compare the periapical healing of teeth with asymptomatic apical periodontitis treated either by conventional apical preparation (CAP) or apical clearing technique (ACT). Materials and Methods: Twenty subjects with bilateral nonvital similar teeth exhibiting comparable periapical index (PAI) score were enrolled and randomly allocated. Group I (CAP, n = 20): Apical preparation three sizes greater (master apical file [MAF]) than the first binding file at the established working length. Group II (ACT, n = 20): Apical preparation three sizes greater than the MAF that was followed by dry reaming. Root canal therapy was accomplished in single-visit for all the teeth. They were pursued radiographically at 3, 6, 9 and 12 months. Pre- and post-treatment PAI scores were compared. To ascertain the proportion of healed teeth between the two groups, McNemar Chi-square test was applied. Results: At 3, 6, and 9 months’ time interval the proportion of healed teeth for Group II (ACT) was greater in comparison to Group I (CAP) (P < 0.05). However, at 12 months follow-up period this difference was not significant (P = 0.08). Conclusion: ACT enhanced the healing kinetics. However, the long-term (12 months) radiographic outcome was similar for either technique. PMID:27656054

  8. Differentiation of Apical Bud Cells in a Newly Developed Apical Bud Transplantation Model Using GFP Transgenic Mice as Donor

    Science.gov (United States)

    Sakagami, Ryuji; Yoshinaga, Yasunori; Okamura, Kazuhiko

    2016-01-01

    Rodent mandibular incisors have a unique anatomical structure that allows teeth to grow throughout the lifetime of the rodent. This report presents a novel transplantation technique for studying the apical bud differentiation of rodent mandibular incisors. Incisal apical end tissue with green fluorescent protein from transgenic mouse was transplanted to wild type mice, and the development of the transplanted cells were immunohistologically observed for 12 weeks after the transplantation. Results indicate that the green fluorescent apical end tissue replaced the original tissue, and cells from the apical bud differentiated and extended toward the incisal edge direction. The immunostaining with podoplanin also showed that the characteristics of the green fluorescent tissue were identical to those of the original. The green fluorescent cells were only found in the labial side of the incisor up to 4 weeks. After 12 weeks, however, they were also found in the lingual side. Here the green fluorescent cementocyte-like cells were only present in the cementum close to the dentin surface. This study suggests that some of the cells that form the cellular cementum come from the apical tissue including the apical bud in rodent incisors. PMID:26978064

  9. Changes of the Unique Odontogenic Properties of Rat Apical Bud Cells under the Developing Apical Complex Microenvironment

    Institute of Scientific and Technical Information of China (English)

    Jun Fang; Liang Tang; Xiao-hui Liu; Ling-ying Wen; Yan Jin

    2009-01-01

    Aim To characterize the odontogenic capability of apical bud and phenotypical change of apical bud cells (ABCs) in different microenvironment. Methodology Incisor apical bud tissues from neonatal SD rat were dissected and transplanted into the renal capsules to determine their odontogenic capability. Meanwhile ABCs were cultured and purified by repeated differential trypsinization. Then ABCs were cultured with conditioned medium from developing apical complex cells (DAC-CM). Immunocytochemistry, reverse transcriptase polymerase chain reaction (RT-PCR) and scanning electron microscope (SEM) were performed to compare the biological change of ABC treated with or without DAC-CM. Results First we confirmed the ability of apical bud to form crown-like structure ectopically. Equally important, by using the developing apical complex (DAC) conditioned medium, we found the microenvironment created by root could abrogate the "crown" features of ABCs and promote their proliferation and differentiation. Conclusion ABCs possess odontogenic capability to form crown-like tissues and this property can be affected by root-produced microenvironment.

  10. Five-year longitudinal assessment of the prognosis of apical microsurgery

    DEFF Research Database (Denmark)

    von Arx, Thomas; Jensen, Simon S; Hänni, Stefan;

    2012-01-01

    Apical surgery is an important treatment option for teeth with post-treatment apical periodontitis. Knowledge of the long-term prognosis is necessary when weighing apical surgery against alternative treatments. This study assessed the 5-year outcome of apical surgery and its predictors in a cohor...

  11. Model-Based Development and Evaluation of Control for Complex Multi-Domain Systems: Attitude Control for a Quadrotor UAV

    DEFF Research Database (Denmark)

    Grujic, Ivan; Nilsson, Rene

    Unmanned Aerial Vehicle (UAV) has been constructed and used to develop an attitude controller based on Model Predictive Control (MPC). The MPC controller has been compared to an existing open source Proportional Integral Derivative (PID) attitude controller. This thesis contributes to the discipline...

  12. [Endodontic re-treatment or apical surgery, is an evidence-based choice possible?].

    Science.gov (United States)

    de Lange, J

    2016-02-01

    Treatment of a recurrence after an initial endodontic treatment can consist of endodontic re-treatment or apical surgery. The literature reports comparable success rates for these two options. However, randomised controlled trials that are truly comparable to each other are unavailable as a result of which comparison and an informed choice are not really possible. In addition to the treatment outcome, consideration also has to be given to cost-effectiveness and other patient-related factors, such as pain, swelling and medication. Regarding these considerations, too, little reliable information can be found in the literature. Moreover, factors relating to insurance play an important role in the Netherlands, where only apical surgery is covered by the basic healthcare insurance. In conclusion, all of these factors should be carefully considered before proceeding to an individual treatment strategy. PMID:26878715

  13. Fc receptor endocytosis is controlled by a cytoplasmic domain determinant that actively prevents coated pit localization

    OpenAIRE

    1992-01-01

    Macrophages and B-lymphocytes express two major isoforms of Fc receptor (FcRII-B2 and FcRII-B1) that exhibit distinct capacities for endocytosis. This difference in function reflects the presence of an in- frame insertion of 47 amino acids in the cytoplasmic domain of the lymphocyte isoform (FcRII-B1) due to alternative mRNA splicing. By expressing wild type and mutant FcRII cDNAs in fibroblasts, we have now examined the mechanism by which the insertion acts to prevent coated pit localization...

  14. Bony change of apical lesion healing process using fractal analysis

    International Nuclear Information System (INIS)

    To investigate the change of bone healing process after endodontic treatment of the tooth with an apical lesion by fractal analysis. Radiographic images of 35 teeth from 33 patients taken on first diagnosis, 6 months, and 1 year after endodontic treatment were selected. Radiographic images were taken by JUPITER computerized Dental X-ray System. Fractal dimensions were calculated three times at each area by Scion Image PC program. Rectangular region of interest (30 x 30) were selected at apical lesion and normal apex of each image. The fractal dimension at apical lesion of first diagnosis (L0) is 0.940 ± 0.361 and that of normal area (N0) is 1.186 ± 0.727 (p1) is 1.076 ± 0.069 and that of normal area (N1) is 1.192 ± 0.055 (p2) is 1.163 ± 0.074 and that of normal area (N2) is 1.225 ± 0.079 (p<0.05). After endodontic treatment, the fractal dimensions at each apical lesions depending on time showed statistically significant difference. And there are statistically significant different between normal area and apical lesion on first diagnosis, 6 months after, 1 year after. But the differences were grow smaller as time flows. The evaluation of the prognosis after the endodontic treatment of the apical lesion was estimated by bone regeneration in apical region. Fractal analysis was attempted to overcome the limit of subjective reading, and as a result the change of the bone during the healing process was able to be detected objectively and quantitatively.

  15. Dynein regulates epithelial polarity and the apical localization of stardust A mRNA.

    Science.gov (United States)

    Horne-Badovinac, Sally; Bilder, David

    2008-01-01

    Intense investigation has identified an elaborate protein network controlling epithelial polarity. Although precise subcellular targeting of apical and basolateral determinants is required for epithelial architecture, little is known about how the individual determinant proteins become localized within the cell. Through a genetic screen for epithelial defects in the Drosophila follicle cells, we have found that the cytoplasmic Dynein motor is an essential regulator of apico-basal polarity. Our data suggest that Dynein acts through the cytoplasmic scaffolding protein Stardust (Sdt) to localize the transmembrane protein Crumbs, in part through the apical targeting of specific sdt mRNA isoforms. We have mapped the sdt mRNA localization signal to an alternatively spliced coding exon. Intriguingly, the presence or absence of this exon corresponds to a developmental switch in sdt mRNA localization in which apical transcripts are only found during early stages of epithelial development, while unlocalized transcripts predominate in mature epithelia. This work represents the first demonstration that Dynein is required for epithelial polarity and suggests that mRNA localization may have a functional role in the regulation of apico-basal organization. Moreover, we introduce a unique mechanism in which alternative splicing of a coding exon is used to control mRNA localization during development.

  16. Dynein regulates epithelial polarity and the apical localization of stardust A mRNA.

    Directory of Open Access Journals (Sweden)

    Sally Horne-Badovinac

    2008-01-01

    Full Text Available Intense investigation has identified an elaborate protein network controlling epithelial polarity. Although precise subcellular targeting of apical and basolateral determinants is required for epithelial architecture, little is known about how the individual determinant proteins become localized within the cell. Through a genetic screen for epithelial defects in the Drosophila follicle cells, we have found that the cytoplasmic Dynein motor is an essential regulator of apico-basal polarity. Our data suggest that Dynein acts through the cytoplasmic scaffolding protein Stardust (Sdt to localize the transmembrane protein Crumbs, in part through the apical targeting of specific sdt mRNA isoforms. We have mapped the sdt mRNA localization signal to an alternatively spliced coding exon. Intriguingly, the presence or absence of this exon corresponds to a developmental switch in sdt mRNA localization in which apical transcripts are only found during early stages of epithelial development, while unlocalized transcripts predominate in mature epithelia. This work represents the first demonstration that Dynein is required for epithelial polarity and suggests that mRNA localization may have a functional role in the regulation of apico-basal organization. Moreover, we introduce a unique mechanism in which alternative splicing of a coding exon is used to control mRNA localization during development.

  17. Effect of nickel titanium file design on the root surface strain and apical microcracks.

    Science.gov (United States)

    Jamleh, Ahmed; Adorno, Carlos G; Ebihara, Arata; Suda, Hideaki

    2016-04-01

    The aim of this study was to determine the effect of nickel titanium file design on the root surface strain generated and apical microcracks caused during canal shaping. Thirty-three mandibular incisors were distributed into LightSpeed X, FlexMaster and a control group. A strain gauge was fixed apically on the proximal root surface to determine the maximum strain during canal shaping. Except for the control group, all root canals were enlarged to size 50. Images were taken after removing the apical 1 and 2 mm of the root end. Mean maximum strain values and presence of microcracks were statistically compared using the t-test and chi-square test, respectively. During canal shaping, the strain increased cumulatively with mean maximum strains of 808.2 ± 228.8 and 525.1 ± 168.9 microstrain in LightSpeed X and FlexMaster, respectively (P = 0.004). Both systems caused comparable microcracks. Although LightSpeed X produced higher maximum strain, no difference in microcrack development was found between both systems.

  18. Effect of nickel titanium file design on the root surface strain and apical microcracks.

    Science.gov (United States)

    Jamleh, Ahmed; Adorno, Carlos G; Ebihara, Arata; Suda, Hideaki

    2016-04-01

    The aim of this study was to determine the effect of nickel titanium file design on the root surface strain generated and apical microcracks caused during canal shaping. Thirty-three mandibular incisors were distributed into LightSpeed X, FlexMaster and a control group. A strain gauge was fixed apically on the proximal root surface to determine the maximum strain during canal shaping. Except for the control group, all root canals were enlarged to size 50. Images were taken after removing the apical 1 and 2 mm of the root end. Mean maximum strain values and presence of microcracks were statistically compared using the t-test and chi-square test, respectively. During canal shaping, the strain increased cumulatively with mean maximum strains of 808.2 ± 228.8 and 525.1 ± 168.9 microstrain in LightSpeed X and FlexMaster, respectively (P = 0.004). Both systems caused comparable microcracks. Although LightSpeed X produced higher maximum strain, no difference in microcrack development was found between both systems. PMID:26420627

  19. Multi-objective actuator placement optimization for local sound control evaluated in a stochastic domain

    OpenAIRE

    Airaksinen, Tuomas; Aittokoski, Timo

    2012-01-01

    A method to find optimal locations and properties of anti-noise actuators in a local noise control system is considered. The local noise control performance is approximated by an approach based on a finite element method, attempting to estimate the average performance of an optimal active noise control (ANC) system. Local noise control uses a fixed number of circular actuators that are located on the boundary of a three-dimensional enclosed acoustic space. Actuator signals are used to minimiz...

  20. Inhibitory Spillover : Increased Urination Urgency Facilitates Impulse Control in Unrelated Domains

    NARCIS (Netherlands)

    Tuk, Mirjam A.; Trampe, Debra; Warlop, Luk

    2011-01-01

    Visceral states are known to reduce the ability to exert self-control. In the current research, we investigated how self-control is affected by a visceral factor associated with inhibition rather than with approach: bladder control. We designed four studies to test the hypothesis that inhibitory sig

  1. Adolescents' Perceived Control in the Sociopolitical Domain: A Latent Class Analysis

    Science.gov (United States)

    Christens, Brian D.; Peterson, N. Andrew; Reid, Robert J.; Garcia-Reid, Pauline

    2015-01-01

    Sociopolitical control (SPC) has been identified as a critical component of empowerment, resilience and civic development among young people. Sociopolitical control has been assessed according to a two dimensional model: (1) leadership competence and (2) policy control. Very little is known, however, about heterogeneity of perceptions of SPC, how…

  2. Functional Apical Large Conductance, Ca2+-activated, and Voltage-dependent K+ Channels Are Required for Maintenance of Airway Surface Liquid Volume*

    OpenAIRE

    Manzanares, Dahis; Gonzalez, Carlos; Ivonnet, Pedro; Chen, Ren-Shiang; Valencia-Gattas, Monica; Gregory E. Conner; Larsson, H. Peter; Salathe, Matthias

    2011-01-01

    Large conductance, Ca2+-activated, and voltage-dependent K+ (BK) channels control a variety of physiological processes in nervous, muscular, and renal epithelial tissues. In bronchial airway epithelia, extracellular ATP-mediated, apical increases in intracellular Ca2+ are important signals for ion movement through the apical membrane and regulation of water secretion. Although other, mainly basolaterally expressed K+ channels are recognized as modulators of ion transport in airway epithelial ...

  3. A synthesis of evidence on inhibitory control and auditory hallucinations based on the Research Domain Criteria (RDoC framework.

    Directory of Open Access Journals (Sweden)

    Johanna C. Badcock

    2014-03-01

    Full Text Available The National Institute of Mental Health initiative called the Research Domain Criteria (RDoC project aims to provide a new approach to understanding mental illness grounded in the fundamental domains of human behaviour and psychological functioning. To this end the RDoC framework encourages researchers and clinicians to think outside the [diagnostic]box, by studying symptoms, behaviours or biomarkers that cut across traditional mental illness categories. In this article we examine and discuss how the RDoC framework can improve our understanding of psychopathology by zeroing in on hallucinations- now widely recognized as a symptom that occurs in a range of clinical and non-clinical groups. We focus on a single domain of functioning - namely cognitive [inhibitory] control - and assimilate key findings structured around the basic RDoC units of analysis, which span the range from observable behaviour to molecular genetics. Our synthesis and critique of the literature provides a deeper understanding of the mechanisms involved in the emergence of auditory hallucinations, linked to the individual dynamics of inhibitory development before and after puberty; favours separate developmental trajectories for clinical and nonclinical hallucinations; yields new insights into co-occurring emotional and behavioural problems; and suggests some novel avenues for treatment.

  4. Stabilization and control of subcritical semilinear wave equation in bounded domain with Cauchy-Ventcel boundary conditions

    Institute of Scientific and Technical Information of China (English)

    A.Kanoune; N.Mehidi

    2008-01-01

    We analyze the exponential decay property of solutions of the semilinear wave equation in bounded domain Q of RN with a damping term which is effective on the exterior of a ball and boundary conditions of the Cauchy-ventcel type.Under suitable and natural assumptions on the nonlinearity,we prove that the exponential decay holds locally uniformly for finite energy solutions provided the nonlinearity is subcritical at infinity.Subcriticality means,roughly speaking,that the nonlinearity grows at infinity at most as a power P<5.The results obtained in R3 and RN by B.Dehman,G.Lebeau and E.Zuazua on the inequalities of the classical energv(which estimate the total energy of solutions in terms of the energy localized in the exterior of a ball)and on Strichartz's estimates,allow us to give an application to the stabilization controllability of the semilinear wave equation in a bounded domain of RN with a subcritical nonlinearity on the domain and its boundary,and conditions on the boundary of Cauchy-Vlentcel type.

  5. Design of Control Plane Architecture Based on Cloud Platform and Experimental Network Demonstration for Multi-domain SDON

    Science.gov (United States)

    Li, Ming; Yin, Hongxi; Xing, Fangyuan; Wang, Jingchao; Wang, Honghuan

    2016-02-01

    With the features of network virtualization and resource programming, Software Defined Optical Network (SDON) is considered as the future development trend of optical network, provisioning a more flexible, efficient and open network function, supporting intraconnection and interconnection of data centers. Meanwhile cloud platform can provide powerful computing, storage and management capabilities. In this paper, with the coordination of SDON and cloud platform, a multi-domain SDON architecture based on cloud control plane has been proposed, which is composed of data centers with database (DB), path computation element (PCE), SDON controller and orchestrator. In addition, the structure of the multidomain SDON orchestrator and OpenFlow-enabled optical node are proposed to realize the combination of centralized and distributed effective management and control platform. Finally, the functional verification and demonstration are performed through our optical experiment network.

  6. Neumann boundary controllability of the Gear-Grimshaw system with critical size restrictions on the spatial domain

    Science.gov (United States)

    Capistrano-Filho, Roberto A.; Gallego, Fernando A.; Pazoto, Ademir F.

    2016-10-01

    In this paper, we study the boundary controllability of the Gear-Grimshaw system posed on a finite domain (0, L), with Neumann boundary conditions: ut + uu_x+u_{xxx} + a v_{xxx} + a_1vv_x+a_2 (uv)_x =0, & {in} (0,L)× (0,T), c v_t +rv_x +vv_x+abu_{xxx} +v_{xxx}+a_2buu_x+a_1b(uv)_x =0, &{in} (0,L)× (0,T), u_{xx}(0,t)=h_0(t), u_x(L,t)=h_1(t), u_{xx}(L,t)=h_2(t), &{in} (0,T), v_{xx}(0,t)=g_0(t), v_x(L,t)=g_1(t), v_{xx}(L,t)=g_2(t), &{in} (0,T), u(x,0)= u^0(x), quad v(x,0)= v^0(x), & {in} (0,L). We first prove that the corresponding linearized system around the origin is exactly controllable in {(L^2(0,L))^2} when h 2( t) = g 2( t) = 0. In this case, the exact controllability property is derived for any L > 0 with control functions {h_0, g_0 in H^{-1/3}(0,T)} and {h_1, g_1in L^2(0,T)}. If we change the position of the controls and consider {h_0(t)=h_2(t)=0} (resp. {g_0(t)=g_2(t)=0)}, we obtain the result with control functions {g_0, g_2in H^{-1/3}(0,T)} and {h_1, g_1in L^2(0,T)} if and only if the length L of the spatial domain (0, L) does not belong to a countable set. In all cases, the regularity of the controls are sharp in time. If only one control act in the boundary condition, {h_0(t)=g_0(t)=h_2(t)=g_2(t)=0} and g 1( t) = 0 (resp. h 1( t) = 0), the linearized system is proved to be exactly controllable for small values of the length L and large time of control T. Finally, the nonlinear system is shown to be locally exactly controllable via the contraction mapping principle, if the associated linearized systems are exactly controllable.

  7. Effect of dipole-dipole interaction on self-control magnetization oscillation in double-domain nanomagnets

    Science.gov (United States)

    Gao, Y. J.; Guo, Y. J.; Liu, J.-M.

    2012-03-01

    A double-domain model with long-range dipole-dipole interaction is proposed to investigate the self-oscillation of magnetization in nano-magnetic systems driven by self-controlled spin-polarized current. The dynamic behavior of magnetization oscillation is calculated by a modified Landau-Lifshitz-Gilbert equation in order to evaluate the effects of the long-range dipole-dipole interaction. While the self-oscillation of magnetization can be maintained substantially, several self-oscillation regions are experienced as the dipole-dipole interaction increases gradually.

  8. Control of magnetic relaxation by electric-field-induced ferroelectric phase transition and inhomogeneous domain switching

    Science.gov (United States)

    Nan, Tianxiang; Emori, Satoru; Peng, Bin; Wang, Xinjun; Hu, Zhongqiang; Xie, Li; Gao, Yuan; Lin, Hwaider; Jiao, Jie; Luo, Haosu; Budil, David; Jones, John G.; Howe, Brandon M.; Brown, Gail J.; Liu, Ming; Sun, Nian

    2016-01-01

    Electric-field modulation of magnetism in strain-mediated multiferroic heterostructures is considered a promising scheme for enabling memory and magnetic microwave devices with ultralow power consumption. However, it is not well understood how electric-field-induced strain influences magnetic relaxation, an important physical process for device applications. Here, we investigate resonant magnetization dynamics in ferromagnet/ferroelectric multiferroic heterostructures, FeGaB/PMN-PT and NiFe/PMN-PT, in two distinct strain states provided by electric-field-induced ferroelectric phase transition. The strain not only modifies magnetic anisotropy but also magnetic relaxation. In FeGaB/PMN-PT, we observe a nearly two-fold change in intrinsic Gilbert damping by electric field, which is attributed to strain-induced tuning of spin-orbit coupling. By contrast, a small but measurable change in extrinsic linewidth broadening is attributed to inhomogeneous ferroelastic domain switching during the phase transition of the PMN-PT substrate.

  9. Control of magnetic relaxation by electric-field-induced ferroelectric phase transition and inhomogeneous domain switching

    Energy Technology Data Exchange (ETDEWEB)

    Nan, Tianxiang; Emori, Satoru; Wang, Xinjun; Hu, Zhongqiang; Xie, Li; Gao, Yuan; Lin, Hwaider; Sun, Nian, E-mail: n.sun@neu.edu [Department of Electrical and Computer Engineering, Northeastern University, Boston, Massachusetts 02115 (United States); Peng, Bin; Liu, Ming, E-mail: mingliu@mail.xjtu.edu.cn [Electronic Materials Research Laboratory, Xi' an Jiaotong University, Xi' an 710049 (China); Jiao, Jie; Luo, Haosu [Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 201800 (China); Budil, David [Department of Chemistry, Northeastern University, Boston, Massachusetts 02115 (United States); Jones, John G.; Howe, Brandon M.; Brown, Gail J. [Materials and Manufacturing Directorate, Air Force Research Laboratory, Wright-Patterson AFB, Ohio 45433 (United States)

    2016-01-04

    Electric-field modulation of magnetism in strain-mediated multiferroic heterostructures is considered a promising scheme for enabling memory and magnetic microwave devices with ultralow power consumption. However, it is not well understood how electric-field-induced strain influences magnetic relaxation, an important physical process for device applications. Here, we investigate resonant magnetization dynamics in ferromagnet/ferroelectric multiferroic heterostructures, FeGaB/PMN-PT and NiFe/PMN-PT, in two distinct strain states provided by electric-field-induced ferroelectric phase transition. The strain not only modifies magnetic anisotropy but also magnetic relaxation. In FeGaB/PMN-PT, we observe a nearly two-fold change in intrinsic Gilbert damping by electric field, which is attributed to strain-induced tuning of spin-orbit coupling. By contrast, a small but measurable change in extrinsic linewidth broadening is attributed to inhomogeneous ferroelastic domain switching during the phase transition of the PMN-PT substrate.

  10. Parameterised controller synthesis for SISO-LTI uncertain plants using frequency domain information

    Science.gov (United States)

    Parastvand, Hossein; Khosrowjerdi, Mohammad-Javad

    2016-01-01

    This paper extends the results of a new model-free approach which has been applied to guarantee nominal stability and performance. In this paper, using a particular controller structure, the robust stability (RS) and robust performance (RP) criteria for single input single output linear time invariant (SISO-LTI) plants with multiplicative uncertainty are transformed to affine functions in terms of controller parameters. It is shown that solving the feasibility problem of these new criteria will lead to controllers that guarantee the RS and performance. There is no need for a plant mathematical model. The required data for controller synthesis are just the frequency responses corresponding to limited samples of the uncertain plant. Also, there is no need for exact data at each frequency for the whole set of frequency responses. The approach is also applicable for designing both low- and high-order controllers. The effectiveness of the proposed technique is illustrated by simulation results.

  11. Cryopreservation of Pelargonium apices by droplet-vitrification.

    Science.gov (United States)

    Gallard, Anthony; Panis, Bart; Dorion, Nöelle; Swennen, Rony; Grapin, Agnès

    2008-01-01

    The droplet-vitrification method was adapted to Pelargonium apices by optimizing the duration of the loading solution (LS) as well as the plant vitrification solution 2 (PVS2). The excised apices were dehydrated in two steps (20 min in LS and 15 min in PVS2) and then immersed directly in liquid nitrogen (LN). After thawing and unloading in the recovery solution at room temperature for 15 min, apices were plated onto semi-solid Murashige and Skoog medium. This simple protocol without any pretreatment was successfully applied to eight cultivars with a survival level ranging between 55.6 - 96.2 percent and a regrowth level between 9.1 and 70.6 percent. These results prove the feasibility of the long-term storage of Pelargonium germplasm through cryopreservation.

  12. Comparing the apical microleakage of lateral condensation and chloroform dip techniques with a new obturation method

    Directory of Open Access Journals (Sweden)

    Masoud Saatchi

    2011-01-01

    Full Text Available Background: The final objective of root canal therapy is to create a hermetic seal along the length of the root canal system. For this purpose, many methods and materials have been introduced. The purpose of this study was to compare the apical microleakage in a new obturation technique (true-tug-back with two other obturation techniques (lateral condensation and chloroform dip technique. Methods: In this in vitro study 102 single canal teeth were selected. The crowns were removed, and the canals were prepared using step-back technique. The master apical file was K-file #40. The teeth were divided into 3 experimental groups of 32 teeth. First group were obturated with lateral condensation technique and second group with chloroform dip technique and the third group with true-tug-back technique. Six teeth were used as control group. The teeth were placed in incubator at 100% humidity and 37°c for three days. The roots of the teeth were coated with two layers of nail varnish except for the apical 2 millimeter. Teeth were placed in Methylene blue 2% for one week. The teeth were sectioned vertically and the depth of maximum dye penetration for each tooth was recorded by stereomicroscope. Data were analyzed using ANOVA and Dunkan test. Results: The mean liner dye penetration differences between lateral condensation group (6.88 ± 4.06 mm and chloroform dip technique group (7.16 ± 3.37 mm were not statistically significant (P = 0.719. The differences between true-tug-back group (3.15 ± 0.52 mm and two other groups were statistically significant (P < 0.001. Conclusion: The results of this study showed that the true-tug-back technique can improve apical seal. Further studies are needed for this purpose.

  13. Sealing ability of grar MTA AngelusTM, CPM TM and MBPc used as apical plugs.

    Science.gov (United States)

    Orosco, Fernando Accorsi; Bramante, Clovis Monteiro; Garcia, Roberto Brandão; Bernadineli, Norberti; Moraes, Ivaldo Gomes de

    2008-01-01

    This study evaluated the sealing ability of apical plugs fabricated with gray MTA Angelus sealer, CPM TM sealer and MBPc sealer. The root canals of 98 extracted single-rooted human teeth were instrumented with #5 to #1 Gates Glidden drills according to the crown-down technique until the #1 drill could pass through the apical foramen. The specimens were then prepared with K-files, starting with an ISO 50 until an ISO 90 could be visualized 1 mm beyond the apex. After root canal preparation, the external surface of each root was rendered impermeable and roots were assigned to 3 experimental groups (n = 30), which received a 5-mm thick apical plug of gray MTA Angelus, CPM and MBPc, and two control groups (n=4). The remaining portion of the canal in the experimental groups was filled by the lateral condensation technique. The teeth of each group, properly identified, were fixed on utility wax by their crowns and were placed in plastic flasks, leaving the apex free and facing upward. The flasks were filled with 0.2% Rhodamine B solution, pH 7.0, so as to completely cover the root apex of all teeth. The sealing ability was analyzed by measuring 0.2% Rhodamine B leakage after all groups had been maintained in this solution for 48 hours. Data were analyzed statistically by Kruskal-Wallis test and Dunn test with a=5%. The results showed that, among the tested materials used for fabrication of apical plugs, MBPc sealer had the least amount of leakage with statistically significant difference (p<0.05). PMID:19089289

  14. Sealing ability of grar MTA AngelusTM, CPM TM and MBPc used as apical plugs

    Directory of Open Access Journals (Sweden)

    Fernando Accorsi Orosco

    2008-02-01

    Full Text Available This study evaluated the sealing ability of apical plugs fabricated with gray MTA AngelusTM sealer, CPM TM sealer and MBPc sealer. The root canals of 98 extracted single-rooted human teeth were instrumented with #5 to #1 Gates Glidden drills according to the crown-down technique until the #1 drill could pass through the apical foramen. The specimens were then prepared with K-files, starting with an ISO 50 until an ISO 90 could be visualized 1 mm beyond the apex. After root canal preparation, the external surface of each root was rendered impermeable and roots were assigned to 3 experimental groups (n = 30, which received a 5-mm thick apical plug of gray MTA AngelusTM, CPM TM and MBPc, and two control groups (n=4. The remaining portion of the canal in the experimental groups was filled by the lateral condensation technique. The teeth of each group, properly identified, were fixed on utility wax by their crowns and were placed in plastic flasks, leaving the apex free and facing upward. The flasks were filled with 0.2% Rhodamine B solution, pH 7.0, so as to completely cover the root apex of all teeth. The sealing ability was analyzed by measuring 0.2% Rhodamine B leakage after all groups had been maintained in this solution for 48 hours. Data were analyzed statistically by Kruskal-Wallis test and Dunn test with a=5%. The results showed that, among the tested materials used for fabrication of apical plugs, MBPc sealer had the least amount of leakage with statistically significant difference (p<0.05.

  15. Set Domain-Dependent Regulation of Transcriptional Silencing and Growth Control by SUV39H1, a Mammalian Ortholog of Drosophila Su(var)3-9

    OpenAIRE

    Firestein, Ron; Cui, Xiangmin; Huie, Phil; Cleary, Michael L.

    2000-01-01

    Mammalian SET domain-containing proteins define a distinctive class of chromatin-associated factors that are targets for growth control signals and oncogenic activation. SUV39H1, a mammalian ortholog of Drosophila Su(var)3-9, contains both SET and chromo domains, signature motifs for proteins that contribute to epigenetic control of gene expression through effects on the regional organization of chromatin structure. In this report we demonstrate that SUV39H1 represses transcription in a trans...

  16. Lipid domains control myelin basic protein adsorption and membrane interactions between model myelin lipid bilayers.

    Science.gov (United States)

    Lee, Dong Woog; Banquy, Xavier; Kristiansen, Kai; Kaufman, Yair; Boggs, Joan M; Israelachvili, Jacob N

    2014-02-25

    The surface forces apparatus and atomic force microscope were used to study the effects of lipid composition and concentrations of myelin basic protein (MBP) on the structure of model lipid bilayers, as well as the interaction forces and adhesion between them. The lipid bilayers had a lipid composition characteristic of the cytoplasmic leaflets of myelin from "normal" (healthy) and "disease-like" [experimental allergic encephalomyelitis (EAE)] animals. They showed significant differences in the adsorption mechanism of MBP. MBP adsorbs on normal bilayers to form a compact film (3-4 nm) with strong intermembrane adhesion (∼0.36 mJ/m(2)), in contrast to its formation of thicker (7-8 nm) swelled films with weaker intermembrane adhesion (∼0.13 mJ/m(2)) on EAE bilayers. MBP preferentially adsorbs to liquid-disordered submicron domains within the lipid membranes, attributed to hydrophobic attractions. These results show a direct connection between the lipid composition of membranes and membrane-protein adsorption mechanisms that affects intermembrane spacing and adhesion and has direct implications for demyelinating diseases.

  17. IN VIVO ANALYSIS OF SOME KEY CHARACTERISTICS OF THE APICAL ZONE IN TEETH WITH CHRONIC APICAL PERIODONTITIS.

    Directory of Open Access Journals (Sweden)

    Angela Gusiyska

    2014-11-01

    Full Text Available Introduction: The pathogenesis of internal and external resorptive processes in the dental tissues and those of the periapical zone is not fully understood, but the main purpose, either in teeth with internal resorption or in teeth with periapical lesions, is decontamination of the endodontic space and subsequent three-dimensional obturation in order to isolate periapical and oral tissues and prevent reinfection. Purpose: The aim of this article is to analyze in vivo some key characteristics of the apical zone in teeth with chronic apical periodontitis. Material and Methods: To facilitate the clinical protocol after the radiographic analysis and assessment of patency, the working lengths of 153 root canals (n = 153 in 106 teeth were determined. The clinical widths of the apical narrowing were measured by using the last instrument (ISO 0.02 tapered file, which can move freely through the apical narrowing after electrometric determination of the working length (Raypex 5 /VDW, Germany/. Results and Discussion: Determination of working width and working length is important for realizing the first stage of decontamination – maximum instrumentation of the endodontic space and choice of a clinical protocol. The classification of root canals in a particular group according to the relative patency or lysed apical opening is important for the selection of obturation technique, which is essential for reducing the microleakage in the zone. Conclusion: Since the target of this work were teeth with CAP, in the majority of the cases with clinical findings of root canals with preexisting filling, radicular pins, obliteration, separated canal instruments, perforations at different levels, via falsa or thresholds, the access to the apical zone was not subjected to a closely observed instrumental clinical protocol. In the treatment of each case, however, the clinical principles of modern endodontic treatment were closely observed.

  18. Kinase domain insert containing receptor promotor controlled suicide gene system kills human umbilical vein endothelial cells

    Institute of Scientific and Technical Information of China (English)

    Zong-Hai Huang; Wen-Yu Yang; Qi Cheng; Jing-Long Yu; Zhou Li; Zong-Yan Tong; Hui-Juan Song; Xiao-Yan Che

    2005-01-01

    AIM: To evaluate the killing effect of double suicide gene mediated by adenovirus and regulated under kinase domain insert containing receptor (KDR) promoter on human umbilical vein endothelial cells. METHODS: By PCR technology, human KDR promoter gene, Escherichia coli(E. coli) cytosine deaminase (CD) gene and the herpes simple virus-thymidine kinase (TK) gene were cloned. Plasmid pKDR-CDglyTK was constructed with them. Then, a recombinant adenoviral plasmid pAdKDRCDglyTK was constructed in a "two-step transformation protocol". The newly constructed plasmids were transfected to 293 packaging cells to grow adenoviruses, which were further propagated and purified. Human umbilical vein endothelial cells (HUVEC) were infected with a different multiplicity of infection (MOI) of resultant recombinant adenovirus, the infection rate was measured with the aid of (GFP) expression. Infected cells were cultured in culture media containing different concentrations of (GCV) and/or 5-(FC), and the killing effects were measured.RESULTS: Recombinant adenoviruses AdKDR-CDglyTK were successfully constructed, and they infected HUVEC cells efficiently. Our data indicated that the infection rate was relevant to MOI of recombinant adenoviruses. HUVEC cells infected with AdKDR-CDglyTK were highly sensitive to the prodrugs, their survival rate correlated to both the concentration of the prodrugs and the MOI of recombinant adenoviruses. Our data also indicated that the two prodrugs used in combination were much more effective on killing transgeneic cells than GCV or 5-FC used alone. CONCLUSION: Prodrug/KDR-CDglyTK system is effective on killing HUVEC cells, its killing effect correlates to the concentration of prodrugs and recombinant adenovirus' MOI. Combined use of the two prodrugs confers better killing effects on transgeneic cells.

  19. Transient magmatic control in a tectonic domain: the central Aeolian volcanic arc (South Italy)

    KAUST Repository

    Ruch, Joel

    2015-04-01

    The background stress field in volcanic areas may be overprinted by that produced by transient magmatic intrusions, generating local faulting. These events are rarely monitored and thus not fully understood, generating debate about the role of magma and tectonics in any geodynamic setting. Here we carried out a field structural analysis on the NNW-SSE strike-slip system of the central Aeolian Arc, Italy (Lipari and Vulcano islands) with ages constrained by stratigraphy to better capture the tectonic and magmatic evolution at the local and regional scales. We consider both islands as a single magmatic system and define 5 principal stratigraphic units based on magmatic and tectonic activity. We collected >500 measurements of faults, extension fractures and dikes at 40 sites, mostly NNE-SSW to NNW-SSE oriented with a dominant NS orientation. These structures are governed quasi exclusively by pure dip-slip motion, consistent with an E-W extension direction, with minor dextral and sinistral slip, the latter being mostly related to old deposits (>50 ka). We further reconstructed the evolution of the Vulcano-Lipari system during the last ~20 ka and find that it consists of an overall half-graben-like structure, with faults with predominant eastward dips. Field evidence suggests that faulting occurs often in temporal and spatial relation with magmatic events, suggesting that most of the observable deformation derived from transient magmatic activity, rather than from steady regional tectonics. To explain the dominant magmatic and episodic extension in a tectonic dominant domain, we propose a model where the regional N-S trending maximum horizontal stress, responsible for strike-slip activity, locally rotates to vertical in response to transient pressurization of the magmatic system and magma rise below Lipari and Vulcano. This has possibly generated the propagation of N-S trending dikes in the past 1 ka along a 10 km long by 1 km wide crustal corridor, with important

  20. Attention for speaking: domain-general control from the anterior cingulate cortex in spoken word production

    NARCIS (Netherlands)

    Piai, V.; Roelofs, A.P.A.; Acheson, D.J.; Takashima, A.

    2013-01-01

    ulating evidence suggests that some degree of attentional control is required to regulate and monitor processes underlying speaking. Although progress has been made in delineating the neural substrates of the core language processes involved in speaking, substrates associated with regulatory and mon

  1. Microdissection of shoot meristem functional domains.

    Directory of Open Access Journals (Sweden)

    Lionel Brooks

    2009-05-01

    Full Text Available The shoot apical meristem (SAM maintains a pool of indeterminate cells within the SAM proper, while lateral organs are initiated from the SAM periphery. Laser microdissection-microarray technology was used to compare transcriptional profiles within these SAM domains to identify novel maize genes that function during leaf development. Nine hundred and sixty-two differentially expressed maize genes were detected; control genes known to be upregulated in the initiating leaf (P0/P1 or in the SAM proper verified the precision of the microdissections. Genes involved in cell division/growth, cell wall biosynthesis, chromatin remodeling, RNA binding, and translation are especially upregulated in initiating leaves, whereas genes functioning during protein fate and DNA repair are more abundant in the SAM proper. In situ hybridization analyses confirmed the expression patterns of six previously uncharacterized maize genes upregulated in the P0/P1. P0/P1-upregulated genes that were also shown to be downregulated in leaf-arrested shoots treated with an auxin transport inhibitor are especially implicated to function during early events in maize leaf initiation. Reverse genetic analyses of asceapen1 (asc1, a maize D4-cyclin gene upregulated in the P0/P1, revealed novel leaf phenotypes, less genetic redundancy, and expanded D4-CYCLIN function during maize shoot development as compared to Arabidopsis. These analyses generated a unique SAM domain-specific database that provides new insight into SAM function and a useful platform for reverse genetic analyses of shoot development in maize.

  2. Apical transport of influenza A virus ribonucleoprotein requires Rab11-positive recycling endosome.

    Directory of Open Access Journals (Sweden)

    Fumitaka Momose

    Full Text Available Influenza A virus RNA genome exists as eight-segmented ribonucleoprotein complexes containing viral RNA polymerase and nucleoprotein (vRNPs. Packaging of vRNPs and virus budding take place at the apical plasma membrane (APM. However, little is known about the molecular mechanisms of apical transport of newly synthesized vRNP. Transfection of fluorescent-labeled antibody and subsequent live cell imaging revealed that punctate vRNP signals moved along microtubules rapidly but intermittently in both directions, suggestive of vesicle trafficking. Using a series of Rab family protein, we demonstrated that progeny vRNP localized to recycling endosome (RE in an active/GTP-bound Rab11-dependent manner. The vRNP interacted with Rab11 through viral RNA polymerase. The localization of vRNP to RE and subsequent accumulation to the APM were impaired by overexpression of Rab binding domains (RBD of Rab11 family interacting proteins (Rab11-FIPs. Similarly, no APM accumulation was observed by overexpression of class II Rab11-FIP mutants lacking RBD. These results suggest that the progeny vRNP makes use of Rab11-dependent RE machinery for APM trafficking.

  3. [Nonsurgical retreatment in a case of a radiolucent apical lesion].

    Science.gov (United States)

    Vicente Gómez, A; Rodríguez Ponce, A

    1989-01-01

    We present a case of failure that was helpful solved without surgical endodontic treatment. We don't achieve clinical success besides endodontic treatment was twice remade. Finally we decided to put a temporary filling with calcium hydroxide and wait until apical radiolucency disappear and complete our treatment with gutta-percha, sealer and lateral condensation. PMID:2640036

  4. Assessment of apical periodontitis by MRI. A feasibility study

    Energy Technology Data Exchange (ETDEWEB)

    Geibel, M.A. [Ulm Univ. (Germany). Oral and Maxillofacial Surgery; Schreiber, E.S.; Bracher, A.K.; Rasche, V. [Ulm Univ. (Germany). Internal Medicine II; Hell, E.; Ulrici, J. [Sirona Dental Systems GmbH, Bensheim (Germany). Dental Imaging; Sailer, L.K. [DOC Praxisklinik im Wiley, Neu-Ulm (Germany). MKG; Ozpeynirci, Y. [Ulm Univ. (Germany). Diagnostic and Interventional Radiology

    2015-04-15

    The purpose of this clinical feasibility study was to evaluate the applicability of magnetic resonance imaging (MRI) for the assessment of apical periodontitis in direct comparison with cone beam CT (CBCT). 19 consecutive patients (average age 43 ± 13 years) with 34 lesions in total (13 molars, 14 premolars and 7 front teeth) were enrolled in this feasibility study. Periapical lesions were defined as periapical radiolucencies (CBCT) or structural changes in the spongy bone signal (MRI), which were connected with the apical part of a root and with at least twice the width of the periodontal ligament space. The location and dimension of the lesions were compared between MRI and CBCT. While mainly mineralized tissue components such as teeth and bone were visible with CBCT, complimentary information of the soft tissue components was assessable with MRI. The MRI images provided sufficient diagnostic detail for the assessment of the main structures of interest. Heterogeneous contrast was observed within the lesion, with often a clear enhancement close to the apical foramen and the periodontal gap. No difference for lesion visibility was observed between MRI and CBCT. The lesion dimensions corresponded well, but were slightly but significantly overestimated with MRI. A heterogeneous lesion appearance was observed in several patients. Four patients presented with a well circumscribed hyperintense signal in the vicinity of the apical foramen. The MRI capability of soft tissue characterization may facilitate detailed analysis of periapical lesions. This clinical study confirms the applicability of multi-contrast MRI for the identification of periapical lesions.

  5. [Nonsurgical retreatment in a case of a radiolucent apical lesion].

    Science.gov (United States)

    Vicente Gómez, A; Rodríguez Ponce, A

    1989-01-01

    We present a case of failure that was helpful solved without surgical endodontic treatment. We don't achieve clinical success besides endodontic treatment was twice remade. Finally we decided to put a temporary filling with calcium hydroxide and wait until apical radiolucency disappear and complete our treatment with gutta-percha, sealer and lateral condensation.

  6. The apical plasma membrane of chitin-synthesizing epithelia

    Institute of Scientific and Technical Information of China (English)

    Bernard Moussian

    2013-01-01

    Chitin is the second most abundant polysaccharide on earth.It is produced at the apical side of epidermal,tracheal,fore-,and hindgut epithelial cells in insects as a central component of the protective and supporting extracellular cuticle.Chitin is also an important constituent of the midgut peritrophic matrix that encases the food supporting its digestion and protects the epithelium against invasion by possibly ingested pathogens.The enzyme producing chitin is a glycosyltransferase that resides in the apical plasma membrane forming a pore to extrude the chains of chitin into the extracellular space.The apical plasma membrane is not only a platform for chitin synthases but,probably through its shape and equipment with distinct factors,also plays an important role in orienting and organizing chitin fibers.Here,I review findings on the cellular and molecular constitution of the apical plasma membrane of chitin-producing epithelia mainly focusing on work done in the fruit fly Drosophila melanogaster.

  7. Hypertrophic cardiomyopathy with apical left ventricular aneurysm: a case report

    Institute of Scientific and Technical Information of China (English)

    江腾勇; 韩智红; 王京; 吕强; 吴学思

    2002-01-01

    @@ Morphological diversity is one characteristic of hypertrophic cardi omyopathy (HCM), but it is not common that HCM is associated with apical left ve ntricular aneurysm (LVA) without evidence of a coronary artery lesion. We repor t on such a case and review the pathogenesis, manifestations and diagnostic meth ods by collecting the few available papers published on this topic.

  8. Frequency Domain Effect of a Hysteresis Suppression System with Inverse Preisach Model Based Control

    Directory of Open Access Journals (Sweden)

    Hsin-Fang Tsai

    2015-12-01

    Full Text Available The extended Preisach model is used extensively in precision control for its ability to model and thus can be used to suppress the hysteresis phenomenon. Although an inverse model based on the classical Preisach model entails a very high level of computational complexity, recent advances in computer technology has enabled real-time implementation of such models. The extended Preisach model calculates the hysteresis action by fitting the - table in the Preisach model to a surface. One can then calculate the amount of extension and retraction simply by searching for the parameters on the surface. This paper proposes a real-time high speed implementation of a model-based hysteresis elimination control. The experimental results show that the proposed method produces a smaller tracking error with a smooth system output.

  9. Domains and domain loss

    DEFF Research Database (Denmark)

    Haberland, Hartmut

    2005-01-01

    politicians and in the media, especially in the discussion whether some languages undergo ‘domain loss’ vis-à-vis powerful international languages like English. An objection that has been raised here is that domains, as originally conceived, are parameters of language choice and not properties of languages...... theoretical constructs that can explain language choice which were supposed to be a more powerful explanatory tool than more obvious (and observable) parameters like topic, place (setting) and interlocutor. In the meantime, at least in Scandinavia, the term ‘domain’ has been taken up in the debate among...

  10. Terahertz time domain spectroscopy and imaging: Emerging techniques for food process monitoring and quality control

    OpenAIRE

    Gowen, A. A.; O'Sullivan, C.; O'Donnell, C. P.

    2012-01-01

    The Terahertz (THz) region of the electromagnetic spectrum, spanning the range between 100 GHz and 30 THz, has recently enjoyed a renaissance due to technological developments in source and detector components. With the development of THz instrumentation, applications of THz spectroscopy and imaging for quality control of food products have expanded in scope and improved in performance. This article gives an overview of the fundamentals of THz technology and a comprehe...

  11. Modelling, Control and Frequency Domain Analysis of a Tidal Current Conversion System with Onshore Converters

    OpenAIRE

    Sousounis, Marios; Shek, Jonathan; Mueller, Markus

    2015-01-01

    To optimise a tidal energy conversion system, the operation, maintenance and power generation aspects have to be taken into account. As a result the key focus of this study is to propose and investigate an alternative method of implementing a tidal energy conversion system using a pitch-regulated turbine and a variable-speed squirrel cage induction generator with long distance converters. The generator power output can be optimised by utilising variable-speed control strategies allowing the s...

  12. Acidic Residues Control the Dimerization of the N-terminal Domain of Black Widow Spiders’ Major Ampullate Spidroin 1

    Science.gov (United States)

    Bauer, Joschka; Schaal, Daniel; Eisoldt, Lukas; Schweimer, Kristian; Schwarzinger, Stephan; Scheibel, Thomas

    2016-01-01

    Dragline silk is the most prominent amongst spider silks and comprises two types of major ampullate spidroins (MaSp) differing in their proline content. In the natural spinning process, the conversion of soluble MaSp into a tough fiber is, amongst other factors, triggered by dimerization and conformational switching of their helical amino-terminal domains (NRN). Both processes are induced by protonation of acidic residues upon acidification along the spinning duct. Here, the structure and monomer-dimer-equilibrium of the domain NRN1 of Latrodectus hesperus MaSp1 and variants thereof have been investigated, and the key residues for both could be identified. Changes in ionic composition and strength within the spinning duct enable electrostatic interactions between the acidic and basic pole of two monomers which prearrange into an antiparallel dimer. Upon naturally occurring acidification this dimer is stabilized by protonation of residue E114. A conformational change is independently triggered by protonation of clustered acidic residues (D39, E76, E81). Such step-by-step mechanism allows a controlled spidroin assembly in a pH- and salt sensitive manner, preventing premature aggregation of spider silk proteins in the gland and at the same time ensuring fast and efficient dimer formation and stabilization on demand in the spinning duct. PMID:27681031

  13. Intramolecular trimerization, a novel strategy for making multispecific antibodies with controlled orientation of the antigen binding domains.

    Science.gov (United States)

    Alvarez-Cienfuegos, Ana; Nuñez-Prado, Natalia; Compte, Marta; Cuesta, Angel M; Blanco-Toribio, Ana; Harwood, Seandean Lykke; Villate, Maider; Merino, Nekane; Bonet, Jaume; Navarro, Rocio; Muñoz-Briones, Clara; Sørensen, Karen Marie Juul; Mølgaard, Kasper; Oliva, Baldo; Sanz, Laura; Blanco, Francisco J; Alvarez-Vallina, Luis

    2016-01-01

    Here, we describe a new strategy that allows the rapid and efficient engineering of mono and multispecific trivalent antibodies. By fusing single-domain antibodies from camelid heavy-chain-only immunoglobulins (VHHs) to the N-terminus of a human collagen XVIII trimerization domain (TIE(XVIII)) we produced monospecific trimerbodies that were efficiently secreted as soluble functional proteins by mammalian cells. The purified VHH-TIE(XVIII) trimerbodies were trimeric in solution and exhibited excellent antigen binding capacity. Furthermore, by connecting with two additional glycine-serine-based linkers three VHH-TIE(XVIII) modules on a single polypeptide chain, we present an approach for the rational design of multispecific tandem trimerbodies with defined stoichiometry and controlled orientation. Using this technology we report here the construction and characterization of a tandem VHH-based trimerbody capable of simultaneously binding to three different antigens: carcinoembryonic antigen (CEA), epidermal growth factor receptor (EGFR) and green fluorescence protein (GFP). Multispecific tandem VHH-based trimerbodies were well expressed in mammalian cells, had good biophysical properties and were capable of simultaneously binding their targeted antigens. Importantly, these antibodies were very effective in inhibiting the proliferation of human epidermoid carcinoma A431 cells. Multispecific VHH-based trimerbodies are therefore ideal candidates for future applications in various therapeutic areas. PMID:27345490

  14. An auxin responsive CLE gene regulates shoot apical meristem development in Arabidopsis

    Directory of Open Access Journals (Sweden)

    Hongyan eGuo

    2015-05-01

    Full Text Available Plant hormone auxin regulates most, if not all aspects of plant growth and development, including lateral root formation, organ pattering, apical dominance and tropisms. Peptide hormones are peptides with hormone activities. Some of the functions of peptide hormones in regulating plant growth and development are similar to that of auxin, however, the relationship between auxin and peptide hormones remains largely unknown. Here we report the identification of OsCLE48, a rice (Oryza sativa CLE (CLAVATA3/ENDOSPERM SURROUNDING REGION gene, as an auxin response gene, and the functional characterization of OsCLE48 in Arabidopsis and rice. OsCLE48 encodes a CLE peptide hormone that is similar to Arabidopsis CLEs. RT-PCR analysis showed that OsCLE48 was induced by exogenously application of IAA (indole-3-acetic acid, a naturally occurred auxin. Expression of integrated OsCLE48p:GUS reporter gene in transgenic Arabidopsis plants was also induced by exogenously IAA treatment. These results indicate that OsCLE48 is an auxin responsive gene. Histochemical staining showed that GUS activity was detected in all the tissue and organs of the OsCLE48p:GUS transgenic Arabidopsis plants. Expression of OsCLE48 under the control of the 35S promoter in Arabidopsis inhibited shoot apical meristem development. Expression of OsCLE48 under the control of the CLV3 native regulatory elements almost completely complemented clv3-2 mutant phenotypes, suggesting that OsCLE48 is functionally similar to CLV3. On the other hand, expression of OsCLE48 under the control of the 35S promoter in Arabidopsis has little, if any effects on root apical meristem development, and transgenic rice plants overexpressing OsCLE48 are morphologically indistinguishable from wild type plants, suggesting that the functions of some CLE peptides may not be fully conserved in Arabidopsis and rice.

  15. A heme-binding domain controls regulation of ATP-dependent potassium channels.

    Science.gov (United States)

    Burton, Mark J; Kapetanaki, Sofia M; Chernova, Tatyana; Jamieson, Andrew G; Dorlet, Pierre; Santolini, Jérôme; Moody, Peter C E; Mitcheson, John S; Davies, Noel W; Schmid, Ralf; Raven, Emma L; Storey, Nina M

    2016-04-01

    Heme iron has many and varied roles in biology. Most commonly it binds as a prosthetic group to proteins, and it has been widely supposed and amply demonstrated that subtle variations in the protein structure around the heme, including the heme ligands, are used to control the reactivity of the metal ion. However, the role of heme in biology now appears to also include a regulatory responsibility in the cell; this includes regulation of ion channel function. In this work, we show that cardiac KATP channels are regulated by heme. We identify a cytoplasmic heme-binding CXXHX16H motif on the sulphonylurea receptor subunit of the channel, and mutagenesis together with quantitative and spectroscopic analyses of heme-binding and single channel experiments identified Cys628 and His648 as important for heme binding. We discuss the wider implications of these findings and we use the information to present hypotheses for mechanisms of heme-dependent regulation across other ion channels.

  16. Evaluation of Apical Micro-leakage of Different Endodontic Sealers in the Presence and Absence of Moisture.

    Science.gov (United States)

    Ehsani, Maryam; Dehghani, Atena; Abesi, Farida; Khafri, Soraya; Ghadiri Dehkordi, Sara

    2014-01-01

    Background and aims. With availability of hydrophilic sealers, drying of the canals before endodontic obturation is still a matter of debate. The aim of this study was to compare the apical micro-leakage of AH26, Excite DSC, MTA Fillapex, and ZOE sealers in dry and moist root canals. Materials and methods. This experimental study was performed on 90 extracted maxillary central incisors. Rotary files were used for preparation of the canals. Root canals were filled with a single gutta percha cone, using one of the four sealers, under dry and moist root canal conditions (10 teeth in each group). Orifices were sealed with glue wax and all root surfaces were covered with nail polish except the positive control group. After ten days in 100% humidity, teeth were placed in methylene blue, and then were cut in longitudinal axis. Blue color permeability was measured by stereomicroscope in micrometers. Data were analyzed by t-test, ANOVA and Scheffe post hoc test using SPSS V.18 software at P 0.05). Apical micro-leakage was significantly higher in the Excite DSC groups (P < 0.001). Conclusion. AH26 provided the least apical micro-leakage under dry conditions while ZOE had the highest micro-leakage under moist conditions. MTA Fillapex provided acceptable apical seal regardless of moisture. PMID:25346829

  17. Frequency-domain analysis of computer-controlled optical surfacing processes

    Institute of Scientific and Technical Information of China (English)

    ZHOU Lin; DAI YiFan; XIE XuHui; LI ShengYi

    2009-01-01

    Mid-high spatial frequency errors are often induced on optical surfaces polished by computer-controlled optical surfacing (CCOS) processes. In order to efficiently remove these errors, which would degrade the performances of optical systems, the ability of a CCOS process to correct the errors have been investigated based on the convolution integral model in view of the availability of material removal. To quantify the ability, some conceptions, such as figure correcting ability and material removal availability (MRA), have been proposed. The research result reveals that the MRA of the CCOS process to correct a single spatial frequency error is determined by its tool removal function (TRF), and it equals the normalized amplitude spectrum of the Fourier transform of its TRF. Finally, three sine surfaces were etched using ion beam figuring (IBF), which is a typical CCOS process. The experimental results have verified the theoretical analysis. The employed method and the conclusions of this work provide a useful mathematical basis to analyze and optimize CCOS processes.

  18. Implantation of a left ventricular assist device in patients with a complex apical anatomy.

    Science.gov (United States)

    Palmen, Meindert; Verwey, Harriette F; Haeck, Marlieke L A; Holman, Eduard R; Schalij, Martin J; Klautz, Robert J M

    2012-12-01

    Implantation of a left ventricular assist device can be challenging in patients with an altered apical anatomy after cardiac surgery or as the result of the presence of a calcified apical aneurysm. In this paper we present 2 cases with a challenging apical anatomy and introduce a new surgical technique facilitating left ventricular assist device implantation in these patients.

  19. An auxin responsive CLE gene regulates shoot apical meristem development in Arabidopsis.

    Science.gov (United States)

    Guo, Hongyan; Zhang, Wei; Tian, Hainan; Zheng, Kaijie; Dai, Xuemei; Liu, Shanda; Hu, Qingnan; Wang, Xianling; Liu, Bao; Wang, Shucai

    2015-01-01

    Plant hormone auxin regulates most, if not all aspects of plant growth and development, including lateral root formation, organ pattering, apical dominance, and tropisms. Peptide hormones are peptides with hormone activities. Some of the functions of peptide hormones in regulating plant growth and development are similar to that of auxin, however, the relationship between auxin and peptide hormones remains largely unknown. Here we report the identification of OsCLE48, a rice (Oryza sativa) CLE (CLAVATA3/ENDOSPERM SURROUNDING REGION) gene, as an auxin response gene, and the functional characterization of OsCLE48 in Arabidopsis and rice. OsCLE48 encodes a CLE peptide hormone that is similar to Arabidopsis CLEs. RT-PCR analysis showed that OsCLE48 was induced by exogenously application of IAA (indole-3-acetic acid), a naturally occurred auxin. Expression of integrated OsCLE48p:GUS reporter gene in transgenic Arabidopsis plants was also induced by exogenously IAA treatment. These results indicate that OsCLE48 is an auxin responsive gene. Histochemical staining showed that GUS activity was detected in all the tissue and organs of the OsCLE48p:GUS transgenic Arabidopsis plants. Expression of OsCLE48 under the control of the 35S promoter in Arabidopsis inhibited shoot apical meristem development. Expression of OsCLE48 under the control of the CLV3 native regulatory elements almost completely complemented clv3-2 mutant phenotypes, suggesting that OsCLE48 is functionally similar to CLV3. On the other hand, expression of OsCLE48 under the control of the 35S promoter in Arabidopsis has little, if any effects on root apical meristem development, and transgenic rice plants overexpressing OsCLE48 are morphologically indistinguishable from wild type plants, suggesting that the functions of some CLE peptides may not be fully conserved in Arabidopsis and rice. Taken together, our results showed that OsCLE48 is an auxin responsive peptide hormone gene, and it regulates shoot apical

  20. Time domain models for damping-controlled fluidelastic instability forces in multi-span tubes with loose supports

    International Nuclear Information System (INIS)

    This paper presents simulations of a loosely supported multi-span tube subjected to turbulence and fluidelastic instability forces. Several time-domain fluid force models simulating the damping controlled fluidelastic instability mechanism in tube arrays have been presented. These models include the negative damping model based on the Connors equation, fluid force coefficient-based models (Chen and Tanaka and Takahara), and two semi-analytical models (Price and Paidoussis; and Lever and Weaver) were implemented in an in-house finite code. Time domain modeling challenges for each of these theories were discussed. The implemented models were validated against available experimental data. The linear simulations showed that the Connors-equation based model exhibits the most conservative prediction of the critical flow velocity when the recommended design values for the Connors equation were used. The models were then utilized to simulate the nonlinear response of a three-span cantilever tube in a square lattice bar support subjected to air crossflow. The tube was subjected to a single-phase flow passing over one of the tube's spans. For each of these models the flow velocity and the support clearance were varied. Special attention was paid to the tube/support interaction parameters that affect wear, such as impact forces, contact ratio, and normal work rate. As the prediction of the linear threshold varies depending on the utilized model, the nonlinear response also differs. The investigated models exhibit similar response characteristics for the impact force, tip lift response, and work rate. Simulation results show that the Connors-based model underestimates the response and the tube/support interaction parameters for the loose support case. (author)

  1. The impact of measurement frequency on the domains of glycemic control in the critically ill--a Monte Carlo simulation.

    Science.gov (United States)

    Krinsley, James S; Bruns, David E; Boyd, James C

    2015-03-01

    The role of blood glucose (BG) measurement frequency on the domains of glycemic control is not well defined. This Monte Carlo mathematical simulation of glycemic control in a cohort of critically ill patients modeled sets of 100 patients with simulated BG-measuring devices having 5 levels of measurement imprecision, using 2 published insulin infusion protocols, for 200 hours, with 3 different BG-measurement intervals-15 minutes (Q15'), 1 hour (Q1h), and 2 hours (Q2h)-resulting in 1,100,000 BG measurements for 3000 simulated patients. The model varied insulin sensitivity, initial BG value and rate of gluconeogenesis. The primary outcomes included rates of hyperglycemia (BG > 180 mg/dL), hypoglycemia (BG glucose variability (within-patient coefficient of variation [CV] > 20%), and time in range (BG ranges 80-150 mg/dL and 80-180 mg/dL). Percentages of hyperglycemia, hypoglycemia at both thresholds, and patients with elevated glucose variability as well as time outside glycemic targets were substantially higher in simulations with measurement interval Q2h compared to those with measurement interval Q1h and moderately higher in simulations with Q1h than in those with Q15'. Higher measurement frequency mitigated the deleterious effect of high measurement imprecision, defined as CV ≥ 15%. This Monte Carlo simulation suggests that glycemic control in critically ill patients is more optimal with a BG measurement interval no longer than 1h, with further benefit obtained with use of measurement interval of 15'. These findings have important implications for the development of glycemic control standards. PMID:25568143

  2. Through-flow of water in leaves of a submerged plant is influenced by the apical opening

    DEFF Research Database (Denmark)

    Pedersen, Ole; Jørgensen, Lise Bolt; Sand-Jensen, Kaj

    1997-01-01

    Submerged plant, apical opening, hydathode, Sparganium, hydraulic architecture, leaf specific conductivity......Submerged plant, apical opening, hydathode, Sparganium, hydraulic architecture, leaf specific conductivity...

  3. A 10-bit 250 MSPS charge-domain pipelined ADC with replica controlled PVT insensitive BCT circuit

    Science.gov (United States)

    Songren, Huang; Hong, Zhang; Zhenhai, Chen; Shuang, Zhu; Zongguang, Yu; Hongwen, Qian; Yue, Hao

    2015-05-01

    A low power 10-bit 250 MSPS charge-domain (CD) pipelined analog-to-digital converter (ADC) is introduced. The ADC is implemented in MOS bucket-brigade devices (BBDs) based CD pipelined architecture. A replica controlled boosted charge transfer (BCT) circuit is introduced to reject the influence of PVT variations on the charge transfer process. Based on replica controlled BCT, the CD pipelined ADC is designed and realized in a 1P6M 0.18 μm CMOS process. The ADC achieves an SFDR of 64.4 dB, an SNDR of 56.9 dB and an ENOB of 9.2 for a 9.9 MHz input; and an SFDR of 63.1 dB, an SNR of 55.2 dB, an SNDR of 54.5 dB and an ENOB of 8.7 for a 220.5 MHz input at full sampling rate. The DNL is +0.5/ -0.55 LSB and INL is +0.8/ -0.85 LSB. The power consumption of the prototype ADC is only 45 mW at 1.8 V supply and it occupies an active die area of 1.56 mm2. Project supported by the National Natural Science Foundation of China (No. 61106027).

  4. Modelling apical constriction in epithelia using elastic shell theory.

    Science.gov (United States)

    Jones, Gareth Wyn; Chapman, S Jonathan

    2010-06-01

    Apical constriction is one of the fundamental mechanisms by which embryonic tissue is deformed, giving rise to the shape and form of the fully-developed organism. The mechanism involves a contraction of fibres embedded in the apical side of epithelial tissues, leading to an invagination or folding of the cell sheet. In this article the phenomenon is modelled mechanically by describing the epithelial sheet as an elastic shell, which contains a surface representing the continuous mesh formed from the embedded fibres. Allowing this mesh to contract, an enhanced shell theory is developed in which the stiffness and bending tensors of the shell are modified to include the fibres' stiffness, and in which the active effects of the contraction appear as body forces in the shell equilibrium equations. Numerical examples are presented at the end, including the bending of a plate and a cylindrical shell (modelling neurulation) and the invagination of a spherical shell (modelling simple gastrulation). PMID:19859751

  5. Transient apical dyskinesia with a pacemaker: Electrocardiographic features.

    Science.gov (United States)

    Núñez-Gil, Iván J; Feltes, Gisela I; Mejía-Rentería, Hernán D; Biagioni, Corina; De Agustín, J Alberto; Vivas, David; Fernández-Ortiz, Antonio

    2015-04-01

    Transient apical dyskinesia syndromes present features similar to acute coronary syndromes, but with normal coronary arteries and rapid complete resolution of wall motion alterations. We report the case of a 73-year-old woman who was admitted to hospital because of typical chest pain at rest after her brother's death. She had had a pacemaker implanted in 2001. Troponin levels were elevated and apical hypokinesia was shown by ventriculography and echocardiography, with normal coronary arteries. Evolving ECG alterations were observed in spite of the continued pacing rhythm. All these alterations were fully resolved after discharge. This case shows that, even in the presence of a pacemaker, evolving ECG alterations can be observed in Takotsubo syndrome. PMID:25840647

  6. Apical pressures developed by needles for canal irrigation.

    Science.gov (United States)

    Bradford, C E; Eleazer, P D; Downs, K E; Scheetz, J P

    2002-04-01

    Drying instrumented canals with pressurized air may result in patient morbidity or even fatality. Low pressure and side vent needles have been suggested to lessen the danger. This study observed apical pressures from different needles inserted deeply into small round and ovoid canals as instrumentation progressed. Low-pressure (5 psi) air was injected through the needles, and apical pressures were recorded after each instrument. Pressures varied greatly within each test group. Generalities that can be drawn are that binding the needle within the canal gives higher pressures than with the needle slightly short of binding and that pressures were higher with apexes instrumented to size 30 and higher. With the needle tightly bound, neither needle size, needle design, nor canal shape resulted in statistically significant mean pressure differences. With the needle slightly withdrawn, larger bore needles gave higher pressures than small diameter needles. Caution is advised with the clinical use of pressurized air in the drying of root canals. PMID:12043877

  7. Enlargement of the apical gap after laser root resection

    Science.gov (United States)

    Mello, Guilherme P. S.; Paradella, Thais C.; Munin, Egberto; Mello, Jose B.; Pacheco, Marcos T. T.

    2000-11-01

    An apical filling material should establish, as perfect as possible, the hermetic sealing of an apical cavity. However, a gap is formed between the filling material (gutta-percha) and the root canal wall. The egress of irritants into the root canal system to the periapical tissues is considered the principal cause of fails in apicoectomy and retro-filling, being assumed that irritants penetrate mainly through the gap located between the gutta-percha and the dentin. In this paper, we report the observation of an enlargement of the apical gap, after laser apicoectomy, comparing to conventional apicoectomy. The samples were divided into groups, and the conventional apicoectomy group, together with the Er:YAG laser group (400 mJ/10 Hz) produced both similar results, being the gap unaltered. On the other hand, the samples that were irradiated with the Er:YAG laser, followed by Nd:YAG laser irradiation (1.5 W/10 Hz) presented a larger gap, conclusions that were drawn from Scanning Electronic Microscope analysis. The enlargement of the gap was due to the fusion of the dentin on the border, close to the gutta-percha. This pronounced behavior might have been caused by the surface discontinuity, imposing a non-homogeneous condition, in relation to heat propagation, existing many clinical applications of these observations.

  8. Comparative in vitro study of the marginal apical sealing capacity of Sealapex® and Endofill® Sealers

    Directory of Open Access Journals (Sweden)

    Renato Interliche

    Full Text Available Objective: To evaluate the apical seal obtained with two sealers: Sealapex (Kerr-Sybron, Orange, USA a calcium hydroxide-based sealer and Endofill (Dentsply, Petrópolis, Brazil a zinc oxide eugenol-based sealer. Method: Twenty four extracted single-rooted human teeth were divided into two groups, with ten each, instrumented and filled by lateral condensation technique with gutta-percha and one of the sealers. Four teeth were used as positive and negative control. After filling, all specimens were coated with nail vernish except around the apical foramen (the negative control group was completely covered, and then immersed in indian ink for 96 hours, decalcified, dehydrated and diaphanized. Results: The extent of staining was examined under a stereo microscope and the data were statistically analyzed by the Tukey test. Numerically Sealapex (Kerr-Sybron, Orange, USA experimental group had lower levels of marginal leakage than Endofill (Dentsply, Petrópolis, Brasil. The negative control exhibited no leakage and in the positive control leakage was complete. There was no statistically significant differencebetween the sealers. Conclusion: The sealers showed similar apical sealing ability. Neither of the sealers in this study completely prevented leakage.

  9. Dependence of intracellular Na+ concentration on apical and basolateral membrane Na+ influx in frog skin

    International Nuclear Information System (INIS)

    An isotopic method was developed to measure the intracellular Na+ content of the transepithelial Na+ transport pool of frog skin. Isolated epithelia (no corium) were labeled with 24Na either asymmetrically, from apical (Aa) or basolateral (Ab) solutions, or symmetrically (Aab). Transport pool Na+ could be identified from the kinetics of washout of 24Na carried out in the presence of 1 mM ouabain, 100 microM amiloride, and 1 mM furosemide that served to trap cold Na+ and 24Na within the transport pool. In control epithelia, Aab averaged 64.1 neq/cm2 (13.9 mM), and maximal inhibition of apical membrane Na+ entry with 100 microM amiloride caused Aab to decrease to 24.3 neq/cm2 (5.3 mM). Ouabain caused Aab to increase markedly to 303 neq/cm2 in 30 min, whereas amiloride inhibition of apical membrane Na+ entry reduced markedly the rate of increase of Aab caused by ouabain. These data, in part, confirmed the existence of an important basolateral membrane permeability to Na+ that was measured in separate studies of the bidirectional 24Na fluxes at the basolateral membranes of the cells. Both sets of data were supportive of the idea that a significant Na+ recycling exists at the basolateral membranes of the cells that contributes to the Na+ load on the pump and Na+ recycling participates in the regulation of the Na+ concentration of the Na+ transport pool of these epithelial cells

  10. Factors Influencing Selection of Vaginal, Open Abdominal, or Robotic Surgery to Treat Apical Vaginal Vault Prolapse

    Science.gov (United States)

    Anand, Mallika; Weaver, Amy L.; Fruth, Kristin M.; Gebhart, John B.

    2016-01-01

    Objectives To determine factors influencing selection of Mayo-McCall culdoplasty (MMC), open abdominal sacrocolpopexy (ASC), or robotic sacrocolpopexy (RSC) for posthysterectomy vaginal vault prolapse. Methods We retrospectively searched for the records of patients undergoing posthysterectomy apical vaginal prolapse surgery between January 1, 2000, and June 30, 2012, at our institution. Baseline characteristics and explicit selection factors were abstracted from the electronic medical records. Factors were compared between groups using χ2 tests for categorical variables, ANOVA for continuous variables, and Kruskal-Wallis tests for ordinal variables. Results Among the 512 patients identified who met inclusion criteria, the MMC group (n=174) had more patients who were older, American Society of Anesthesiologists class 3+ or greater, had anterior vaginal prolapse grade 3+, desired to avoid abdominal surgery, and did not desire a functional vagina. Patients in the ASC (n=237) and RSC (n=101) groups had more failed prolapse surgeries, suspected abdominopelvic pathologic processes, and chronic pain. Advanced prolapse was more frequently cited as an explicit selection factor for ASC than for either MMC or RSC. Conclusions The most common factors that influenced the type of apical vaginal vault prolapse surgery overlapped with characteristics that differed at baseline. In general, MMC was chosen for advanced anterior vaginal prolapse and baseline characteristics that increased surgical risks, ASC for advanced apical prolapse, and ASC or RSC for recurrent prolapse, suspected abdominal pathology, and patients with chronic pain or lifestyles including heavy lifting. Thus, efforts should be made to attempt to control for selection bias when comparing these procedures. PMID:26945273

  11. Altered Apical Morphology (Reverse Architecture): Use of Indirect Ultrasonic Technique for Orthograde MTA Placement in Maxillary Premolars

    Science.gov (United States)

    Sonali, Kapoor; Suresh, Agrawal Vineet; Abhishek, Patel; Jenish, Patel

    2016-01-01

    Aim. To report the management and orthograde technique of MTA placement in case of reverse architecture maxillary premolars. Summary. Two cases of 17-year-old and 21-year-old female patients were referred to endodontic speciality for management of maxillary premolar having reverse architecture with wide immature open apex like a bell mouth. In both the cases, after control of intraradicular infection, it was decided to use MTA for apexification and obturation of canals. Orthograde placement of MTA is a challenging procedure in terms of length control and condensation especially in divergent irregular reverse architecture wide open apex. A novel technique with the help of finger plugger, sterilized paper point, and ultrasonic agitation for 3D compaction of MTA at apical reverse architecture was used. Thickening of the canal wall and complete apical closure were confirmed one year after the treatment. PMID:27313910

  12. Calcium hydroxide induced apical barrier in fractured nonvital immature permanent incisors

    Directory of Open Access Journals (Sweden)

    Vellore K

    2010-06-01

    Full Text Available Management of trauma to an immature permanent incisor is a challenge, especially when the pulp is necrotic. The aim of this study is to discuss the management of fractured maxillary right and left central incisors with immature root apex. Radiographic evaluation revealed that the tooth 11 had convergent apical walls, whereas tooth 21 had parallel apical walls; both the incisors were treated with pure calcium hydroxide paste to induce apical development. Follow-up clinical and radiographic examinations confirmed apical barrier at 3 months. Radiograph of tooth 11 with convergent roots showed continued apical development, whereas tooth 21 showed apical bridging, following which root canal was completed in both the teeth. Therefore, in view of the simplicity of this method, we believe that calcium hydroxide can be reemphasized as one of the treatment alternatives for fractured nonvital immature permanent incisors to induce apical barrier.

  13. [New echocardiographic para-apical technic for determining the size and thickness of the wall of the right ventricle in probands and patients with dilated cardiomyopathy].

    Science.gov (United States)

    Dyczynski, J; Schweitzer, L

    1987-12-01

    To evaluate the right ventricular size and free wall thickness a new echocardiographic para-apical technique was developed. All cases were examined from the para-apical window in the extreme left lateral decubitus position, on a special mattress that allowed us to investigate the total apical region. The para-apical transducer position makes it possible to cut the right ventricle cross-sectionally in serial bread-loafing fashion from the apex to the base, like the left ventricle. In this way, using the M-mode technique, either diameters and/or right ventricular free wall thickness as well as shortening fraction could be estimated. To estimate the usefulness of the para-apical technique, a study was performed in 50 normal subjects as well as in 16 patients with dilated cardiomyopathy. In all patients, standard views and the new para-apical view were performed. In five cases, contrast echocardiography of the heart was performed to verify the right-heart anatomy. In five patients, computer-tomography of the heart was performed to see the position of the right-heart chambers in the chest and to evaluate the new para-apical ultrasound window. The standard values for the right ventricle in the control group were (in mean values): diastolic diameter, 28.61 +/- 3.19 mm; systolic diameter, 19.10 +/- 2.40 mm; free wall thickness, 4.46 +/- 1.06 mm and shortening fraction, 32.42% +/- 4.02%. The examined parameters in patients with dilated cardiomyopathy were: diastolic diameter, mean value 38.63 +/- 5.80 mm; systolic diameter, mean value 32.48 +/- 4.96 mm; free wall thickness, mean value 8.70 +/- 1.05 mm and shortening fraction, mean value 15.96 +/- 4.02%.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:3439250

  14. Influence of the apical enlargement size on the endotoxin level reduction of dental root canals

    Directory of Open Access Journals (Sweden)

    Ariane Cassia Salustiano Marinho

    2012-12-01

    Full Text Available Gram-negative bacteria play an essential role in endodontic infections because they have virulence factors such as endotoxin. Due to its potential cytotoxic activity, special attention has been given to the removal/neutralization of this endotoxin in the root canal system. OBJECTIVE: The aim of this study was to evaluate the influence of the apical enlargement size (AES by using rotary instruments on the endotoxin level reduction of dental root canals. MATERIAL AND METHODS: Forty root canals of the mandibular premolar teeth were used. Escherichia coli endotoxin (055: B55 was inoculated into thirty root canals. Ten teeth served as the negative control group. After the incubation period, the first endotoxin samples were collected from the root canals with a sterile/apyrogenic paper point for the analysis of the endotoxin units (EU/mL present before instrumentation (S1. Specimen instrumentation was performed with the Mtwo® rotary system in the sequence 10/.04, 15/.05, 20/.06, 25/.06, 30/.05, 35/.04 and 40/.04. To monitor the effectiveness of increasing apical enlargement on endotoxin removal, the second endotoxin samples were collected from all the root canals after instrumentation with the following instruments: #25/.06- (S2; #30/.05- (S3; # 35/.04- (S4; and #40/.04- (S5. Limulus amebocyte lysate (LAL was used to quantify the levels of endotoxin. The results were statistically compared by using repeated measures of ANOVA with post hoc Tukey testing. RESULTS: Increasing levels of endotoxin removal was achieved by large sized apical enlargement: S2 (AES #25/.06- 89.2%, S3 (AES #30/.05- 95.9%, S4 (AES #35/.04- 97.8% and S5 (AES #40/.04- 98.2%. Substantial reduction of endotoxin content was obtained in S4 and S5 compared to S2 (p<0.05, however, the root canal preparation was not able to eliminate the endotoxin. CONCLUSIONS: Under the conditions of this study, it was concluded that the reduction of endotoxin levels of the dental root canals could be

  15. Occurrence of the Transition of Apical Architecture and Expression Patterns of Related Genes during Conversion of Apical Meristem Identity in G2 Pea

    Institute of Scientific and Technical Information of China (English)

    Da-Yong Wang; Qing Li; Ke-Ming Cui; Yu-Xian Zhu

    2009-01-01

    G2 pea exhibits an apical senescence delaying phenotype under short-day (SD) conditions; however, the structural basis for its apical development is still largely unknown. In the present study, the apical meristem of SD-grown G2 pea plants underwent a transition from vegetative to indeterminate inflorescence meristem, but the apical meristem of long-day (LD)-grown G2 pea plants would be further converted to determinate floral meristem. Both SD signal and GA3 treatment enhanced expression of the putative calcium transporter PPF1, and pea homologs of TFL1 (LF and DET), whereas LD signal suppressed their expression at 60 d post-flowering compared with those at 40 d post-flowering. Both PPF1 and LF expressed at the vegetative and reproductive phases in SD-grown apical buds, but floral initiation obviously increased the expression level of PPF1 compared with the unchanged expression level of LF from 40 to 60 d post-flowering. In addition, although the floral initiation significantly enhanced the expression levels of PPF1 and DET, DET was mainly expressed after floral initiation in SD-grown apical buds. Therefore, the main structural difference between LD- and SD-grown apical meristem in G2 pea lies in whether their apical indeterminate inflorescence medstem could be converted to the determinate structure.

  16. The effects of the prevention program 'New Perspectives' (NP) on juvenile delinquency and other life domains: study protocol for a randomized controlled trial

    NARCIS (Netherlands)

    L.A. de Vries; M. Hoeve; J.J. Asscher; G.J.J.M. Stams

    2014-01-01

    Background: New Perspectives (NP) is a prevention program aiming to prevent that youth at onset of a criminal career will develop a persistent criminal behaviour pattern. The effects of NP on juvenile delinquency and other life domains are investigated, using a randomized controlled trial (RCT). Met

  17. Transcytosis of IL-11 and Apical Redirection of gp130 Is Mediated by IL-11α Receptor

    Directory of Open Access Journals (Sweden)

    Niloufar Monhasery

    2016-07-01

    Full Text Available Interleukin (IL-11 signaling is involved in various processes, including epithelial intestinal cell regeneration and embryo implantation. IL-11 signaling is initiated upon binding of IL-11 to IL-11R1 or IL-11R2, two IL-11α-receptor splice variants, and gp130. Here, we show that IL-11 signaling via IL-11R1/2:gp130 complexes occurs on both the apical and basolateral sides of polarized cells, whereas IL-6 signaling via IL-6R:gp130 complexes is restricted to the basolateral side. We show that basolaterally supplied IL-11 is transported and released to the apical extracellular space via transcytosis in an IL-11R1-dependent manner. By contrast, IL-6R and IL-11R2 do not promote transcytosis. In addition, we show that transcytosis of IL-11 is dependent on the intracellular domain of IL-11R1 and that synthetic transfer of the intracellular domain of IL-11R1 to IL-6R promotes transcytosis of IL-6. Our data define IL-11R as a cytokine receptor with transcytotic activity by which IL-11 and IL-6:soluble IL-6R complexes are transported across cellular barriers.

  18. Transcytosis of IL-11 and Apical Redirection of gp130 Is Mediated by IL-11α Receptor.

    Science.gov (United States)

    Monhasery, Niloufar; Moll, Jens; Cuman, Carly; Franke, Manuel; Lamertz, Larissa; Nitz, Rebecca; Görg, Boris; Häussinger, Dieter; Lokau, Juliane; Floss, Doreen M; Piekorz, Roland; Dimitriadis, Eva; Garbers, Christoph; Scheller, Jürgen

    2016-07-26

    Interleukin (IL)-11 signaling is involved in various processes, including epithelial intestinal cell regeneration and embryo implantation. IL-11 signaling is initiated upon binding of IL-11 to IL-11R1 or IL-11R2, two IL-11α-receptor splice variants, and gp130. Here, we show that IL-11 signaling via IL-11R1/2:gp130 complexes occurs on both the apical and basolateral sides of polarized cells, whereas IL-6 signaling via IL-6R:gp130 complexes is restricted to the basolateral side. We show that basolaterally supplied IL-11 is transported and released to the apical extracellular space via transcytosis in an IL-11R1-dependent manner. By contrast, IL-6R and IL-11R2 do not promote transcytosis. In addition, we show that transcytosis of IL-11 is dependent on the intracellular domain of IL-11R1 and that synthetic transfer of the intracellular domain of IL-11R1 to IL-6R promotes transcytosis of IL-6. Our data define IL-11R as a cytokine receptor with transcytotic activity by which IL-11 and IL-6:soluble IL-6R complexes are transported across cellular barriers.

  19. Magi Is Associated with the Par Complex and Functions Antagonistically with Bazooka to Regulate the Apical Polarity Complex

    Science.gov (United States)

    Padash Barmchi, Mojgan; Samarasekera, Gayathri; Gilbert, Mary; Auld, Vanessa J.; Zhang, Bing

    2016-01-01

    The mammalian MAGI proteins play important roles in the maintenance of adherens and tight junctions. The MAGI family of proteins contains modular domains such as WW and PDZ domains necessary for scaffolding of membrane receptors and intracellular signaling components. Loss of MAGI leads to reduced junction stability while overexpression of MAGI can lead to increased adhesion and stabilization of epithelial morphology. However, how Magi regulates junction assembly in epithelia is largely unknown. We investigated the single Drosophila homologue of Magi to study the in vivo role of Magi in epithelial development. Magi is localized at the adherens junction and forms a complex with the polarity proteins, Par3/Bazooka and aPKC. We generated a Magi null mutant and found that Magi null mutants were viable with no detectable morphological defects even though the Magi protein is highly conserved with vertebrate Magi homologues. However, overexpression of Magi resulted in the displacement of Baz/Par3 and aPKC and lead to an increase in the level of PIP3. Interestingly, we found that Magi and Baz functioned in an antagonistic manner to regulate the localization of the apical polarity complex. Maintaining the balance between the level of Magi and Baz is an important determinant of the levels and localization of apical polarity complex. PMID:27074039

  20. Modulation of defect modes intensity by controlled light scattering in photonic crystal with liquid crystal domain structure

    Science.gov (United States)

    Gunyakov, V. A.; Krakhalev, M. N.; Zyryanov, V. Ya.; Shabanov, V. F.; Loiko, V. A.

    2016-07-01

    A method to modulate the defect modes intensity in a multilayer photonic crystal with a nematic liquid crystal layer arranged midmost has been proposed. The various electrohydrodynamic domain structures (Williams domains, oblique rolls and grid pattern) were formed in the nematic layer under the action of ac electric field. The domains cause a polarization-sensitive light scattering which leads to an anisotropic reduction of the defect modes intensity. Thus by varying the applied voltage, we can tune gradually the transmittance spectrum of photonic crystal. In addition, the spectrum strongly depends on the light polarization direction above threshold voltage.

  1. A survey of small RNA population during FR-induced apical hook opening

    Directory of Open Access Journals (Sweden)

    Ying eLi

    2014-04-01

    Full Text Available Photomorphogenesis is a mechanism employed by plants to regulate their architecture and developmental program in response to light conditions. As they emerge into light for the first time, dark-grown seedlings employ a rapid and finely-controlled photomorphogenic signaling network. Small RNAs have increasingly been revealed to play an important role in regulating multiple aspects of plant development, by modulating the stability of mRNAs. The rapid alteration of the mRNA transcriptome is a known hallmark of the de-etiolation response, thus we investigated the small RNA transcriptome during this process in specific seedling tissues. Here we describe a survey of the small RNA expression profile in four tissues of etiolated soybean seedlings, the cotyledons, hypocotyl and the convex and concave sides of the apical hook. We also investigate how this profile responds to a one-hour far-red light treatment. Our data suggests that miRNAs show a different global profile between these tissues and treatments, suggesting a possible role for tissue- and treatment-specific expression in the differential morphology of the seedling on de-etiolation. Further evidence for the role of miRNA in light-regulated development is given by the de-etiolation responses of a hypomorphic ago1 mutant, which displays reduced and delayed photomorphogenic responses in apical hook and cotyledon angle to far-red light.

  2. SHA1, a novel RING finger protein, functions in shoot apical meristem maintenance in Arabidopsis.

    Science.gov (United States)

    Sonoda, Yutaka; Yao, Shan-Guo; Sako, Kaori; Sato, Takeo; Kato, Wataru; Ohto, Masa-aki; Ichikawa, Takanari; Matsui, Minami; Yamaguchi, Junji; Ikeda, Akira

    2007-05-01

    Post-embryonic plant growth is dependent on a functional shoot apical meristem (SAM) that provides cells for continuous development of new aerial organs. However, how the SAM is dynamically maintained during vegetative development remains largely unclear. We report here the characterization of a new SAM maintenance mutant, sha1-1 (shoot apical meristem arrest 1-1), that shows a primary SAM-deficient phenotype at the adult stage. The SHA1 gene encodes a novel RING finger protein, and is expressed most intensely in the shoot apex. We show that, in the sha1-1 mutant, the primary SAM develops normally during the juvenile vegetative stage, but cell layer structure becomes disorganized after entering the adult vegetative stage, resulting in a dysfunctional SAM that cannot initiate floral primordia. The sha1-1 SAM terminates completely at the stage when the wild-type begins to bolt, producing adult plants with a primary inflorescence-deficient phenotype. These observations indicate that SHA1, a putative E3 ligase, is required for post-embryonic SAM maintenance by controlling proper cellular organization. PMID:17461786

  3. Apical Na+ permeability of frog skin during serosal Cl- replacement.

    Science.gov (United States)

    Leibowich, S; DeLong, J; Civan, M M

    1988-05-01

    Gluconate substitution for serosal Cl- reduces the transepithelial short-circuit current (Isc) and depolarizes short-circuited frog skins. These effects could result either from inhibition of basolateral K+ conductance, or from two actions to inhibit both apical Na+ permeability (PapNa) and basolateral pump activity. We have addressed this question by studying whole-and split-thickness frog skins. Intracellular Na+ concentration (CcNa) and PapNa have been monitored by measuring the current-voltage relationship for apical Na+ entry. This analysis was conducted by applying trains of voltage pulses, with pulse durations of 16 to 32 msec. Estimates of PapNa and CcNa were not detectably dependent on pulse duration over the range 16 to 80 msec. Serosal Cl- replacement uniformly depolarized short-circuited tissues. The depolarization was associated with inhibition of Isc across each split skin, but only occasionally across the whole-thickness preparations. This difference may reflect the better ionic exchange between the bulk medium and the extracellular fluid in contact with the basolateral membranes, following removal of the underlying dermis in the split-skin preparations. PapNa was either unchanged or increased, and CcNa either unchanged or reduced after the anionic replacement. These data are incompatible with the concept that serosal Cl- replacement inhibits PapNa and Na,K-pump activity. Gluconate substitution likely reduces cell volume, triggering inhibition of the basolateral K+ channels, consistent with the data and conclusions of S.A. Lewis, A.G. Butt, M.J. Bowler, J.P. Leader and A.D.C. Macknight (J. Membrane Biol. 83:119-137, 1985) for toad bladder. The resulting depolarization reduces the electrical force favoring apical Na+ entry. The volume-conductance coupling serves to conserve volume by reducing K+ solute loss. Its molecular basis remains to be identified. PMID:2458472

  4. Apical Na+ permeability of frog skin during serosal Cl- replacement.

    Science.gov (United States)

    Leibowich, S; DeLong, J; Civan, M M

    1988-05-01

    Gluconate substitution for serosal Cl- reduces the transepithelial short-circuit current (Isc) and depolarizes short-circuited frog skins. These effects could result either from inhibition of basolateral K+ conductance, or from two actions to inhibit both apical Na+ permeability (PapNa) and basolateral pump activity. We have addressed this question by studying whole-and split-thickness frog skins. Intracellular Na+ concentration (CcNa) and PapNa have been monitored by measuring the current-voltage relationship for apical Na+ entry. This analysis was conducted by applying trains of voltage pulses, with pulse durations of 16 to 32 msec. Estimates of PapNa and CcNa were not detectably dependent on pulse duration over the range 16 to 80 msec. Serosal Cl- replacement uniformly depolarized short-circuited tissues. The depolarization was associated with inhibition of Isc across each split skin, but only occasionally across the whole-thickness preparations. This difference may reflect the better ionic exchange between the bulk medium and the extracellular fluid in contact with the basolateral membranes, following removal of the underlying dermis in the split-skin preparations. PapNa was either unchanged or increased, and CcNa either unchanged or reduced after the anionic replacement. These data are incompatible with the concept that serosal Cl- replacement inhibits PapNa and Na,K-pump activity. Gluconate substitution likely reduces cell volume, triggering inhibition of the basolateral K+ channels, consistent with the data and conclusions of S.A. Lewis, A.G. Butt, M.J. Bowler, J.P. Leader and A.D.C. Macknight (J. Membrane Biol. 83:119-137, 1985) for toad bladder. The resulting depolarization reduces the electrical force favoring apical Na+ entry. The volume-conductance coupling serves to conserve volume by reducing K+ solute loss. Its molecular basis remains to be identified.

  5. SEM investigation of Er:YAG laser apical preparation

    Science.gov (United States)

    Bǎlǎbuc, Cosmin; Todea, Carmen; Locovei, Cosmin; RǎduÅ£ǎ, Aurel

    2016-03-01

    Endodontic surgery involves the incision and flap elevation, the access to the root tip, its resection, the cavity retrograde preparation and filling it with biocompatible material that provides a good seal of the apex[1]. Apicoectomy is compulsory in endodontic surgery. The final stage involves the root retropreparation and the carrying out of the retrograde obturation. In order to perform the retrograde preparation the endodontist can use various tools such as lowspeed conventional handpieces, sonic and ultrasonic equipment. The ideal depth of the preparation should be 3 mm, exceeding this value may affect the long-term success of the obturation [2]. Resection at the depth of 3 mm reduces apical ramifications by 98% and lateral root canals by 93%. The ultrasonic retropreparation has numerous advantages compared to the dental drill. Firstly, the cavity will be in the axis of the tooth which implies a minimum destruction of the root canal morphology. The preparations are precise, and the cutting pattern is perpendicular to the long axis of the root, the advantage being the reduction in the number of dentinal tubules exposed at the resected area [3]. Therefore, the retrograde filling is the procedure when an inert and non-toxic material is compacted in the apically created cavity.[4,5]. The Er:YAG laser is the most common wavelength indicated for dental hard tissue preparation. Its natural selectivity offers a significant advantage compared to the conventional hard tissue preparation [6-9].The purpose of this in vitro study was to investigate the quality of Er:YAG laser apical third preparation using Scanning Electron Microscopy (SEM), in comparison with the conventional ultrasonic method.

  6. A comparison of apical sealing ability between GuttaFlow and AH plus: An in vitro study

    Science.gov (United States)

    Patil, Prajakta; Rathore, Vishnu P. S.; Hotkar, Chetan; Savgave, Snehal S.; Raghavendra, K.; Ingale, Priya

    2016-01-01

    Aims: The present study aimed to compare apical sealing ability between GuttaFlow and AH Plus. Materials and Method: Eighty extracted human maxillary anterior teeth with fully formed apex and straight root were collected for this study. The root canals were cleaned and shaped using a standard step back preparation to size 60# master apical file at the established working length and divided into four groups: Group 1, GuttaFlow sealer with gutta-percha; Group 2, AH Plus sealer with gutta-percha; Group 3, positive control group (Teeth were instrumented and left without obturation); Group 4, negative control group (Teeth were totally coated with nail varnish) Dye leakage was carried out. Statistical analysis was done using the Statistical Package for the Social Sciences software and Student's unpaired t-test. Results: The GuttaFlow group had a mean leakage of 1.38 mm whereas AH Plus had a mean of 1.425 mm. The standard deviation of GuttaFlow and AH Plus were 0.3861 and 0.3226, respectively. Student's unpaired t-test disclosed no significant difference (P < 0.05) between the groups. Conclusion: None of the sealers used in the study could completely seal the apical foramen to have a fluid-tight seal. GuttaFlow and AH Plus showed no statistically significant difference in microleakage; the better result was shown by GuttaFlow. PMID:27583228

  7. 基于FODA方法的数控系统领域分析%Domain analysis of numerical control system based on FODA method

    Institute of Scientific and Technical Information of China (English)

    涂荣军; 刘卫东; 陶俊才

    2012-01-01

    从领域系统族的角度开发数控系统,有助于克服在数控应用工程中存在的大量重复开发、开发效率低下等问题.数控领域分析是实施领域工程的关键基础,决定了设计和开发的质量.通过领域分析建立了数控系统族的共用领域需求模型,对于应用系统开发时实现可复用模型的定制具有重要作用.%Developing numerical control system in virtue of domain engineering can solve the problem of repeated development and low-level efficiency development in the numerical control application engineering. Domain analysis is the critical foundation of implementing domain engineering, which conduces to elevating the quality of design and development. The paper has constructed domain requirement model of numerical control system family,which is important to realize customization of reusable model in the application system development.

  8. LATERAL ORGAN BOUNDARIES DOMAIN (LBD)10 interacts with SIDECAR POLLEN/LBD27 to control pollen development in Arabidopsis.

    Science.gov (United States)

    Kim, Min-Jung; Kim, Mirim; Lee, Mi Rha; Park, Soon Ki; Kim, Jungmook

    2015-03-01

    During male gametophyte development in Arabidopsis thaliana, the microspores undergo an asymmetric division to produce a vegetative cell and a generative cell, which undergoes a second division to give rise to two sperm cells. SIDECAR POLLEN/LATERAL ORGAN BOUNDARIES DOMAIN (LBD) 27 plays a key role in the asymmetric division of microspores. Here we provide molecular genetic evidence that a combinatorial role of LBD10 with LBD27 is crucial for male gametophyte development in Arabidopsis. Expression analysis, genetic transmission and pollen viability assays, and pollen development analysis demonstrated that LBD10 plays a role in the male gametophyte function primarily at germ cell mitosis. In the mature pollen of lbd10 and lbd10 expressing a dominant negative version of LBD10, LBD10:SRDX, aberrant microspores such as bicellular and smaller tricellular pollen appeared at a ratio of 10-15% with a correspondingly decreased ratio of normal tricellular pollen, whereas in lbd27 mutants, 70% of the pollen was aborted. All pollen in the lbd10 lbd27 double mutants was aborted and severely shrivelled compared with that of the single mutants, indicating that LBD10 and LBD27 are essential for pollen development. Gene expression and subcellular localization analyses of LBD10:GFP and LBD27:RFP during pollen development indicated that posttranscriptional and/or posttranslational controls are involved in differential accumulation and subcellular localization of LBD10 and LBD27 during pollen development, which may contribute in part to combinatorial and distinct roles of LBD10 with LBD27 in microspore development. In addition, we showed that LBD10 and LBD27 interact to form a heterodimer for nuclear localization.

  9. Effect of different final irrigating solutions on smear layer removal in apical third of root canal: A scanning electron microscope study

    OpenAIRE

    Sayesh Vemuri; Sreeha Kaluva Kolanu; Sujana Varri; Ravi Kumar Pabbati; Ramesh Penumaka; Nagesh Bolla

    2016-01-01

    Aim: The aim of this in vitro study is to compare the smear layer removal efficacy of different irrigating solutions at the apical third of the root canal. Materials and Methods: Forty human single-rooted mandibular premolar teeth were taken and decoronated to standardize the canal length to 14 mm. They were prepared by ProTaper rotary system to an apical preparation of file size F3. Prepared teeth were randomly divided into four groups (n = 10); saline (Group 1; negative control), ethyle...

  10. Domain Engineering

    Science.gov (United States)

    Bjørner, Dines

    Before software can be designed we must know its requirements. Before requirements can be expressed we must understand the domain. So it follows, from our dogma, that we must first establish precise descriptions of domains; then, from such descriptions, “derive” at least domain and interface requirements; and from those and machine requirements design the software, or, more generally, the computing systems.

  11. Selamento apical proporcionado por diferentes cimentos endodônticos

    Directory of Open Access Journals (Sweden)

    Karlel Tristão Marques

    2011-01-01

    Full Text Available To have success in endodontic treatment it is necessary that the sealing airtight as possible of the root canal system, with suitable material such as gutta-percha and sealer. There are sealers of different compositions, which should allow the sealing of the root canal system, preventing recontamination place and favoring the success of endodontic therapy. In this study were evaluated the apical microleakage after obturation using different root canal sealers widely employed in the market, with different compositions. For this study, 85 single rooted teeth premolars which have removed their crowns and root canals prepared and filled using four types of cement: AH Plus, Endofill, Acroseal and Real Seal SE. All samples were sealed and submitted to microleakage with Indian ink; longitudinal cuts made on both sides of the tooth and cleaved; apical images were obtained. The areas of dye penetration were measured on a computer using specific software and subjected to statistical analysis. It was concluded that the Acroseal ® showed the highest mean microleakage with no statistically significant difference in relation to the RealSeal SE®, but with significant differences compared to Endofill ® and AHPlus ®.

  12. Calcium hydroxide as intracanal dressing for teeth with apical periodontitis

    Directory of Open Access Journals (Sweden)

    Sari Dewiyani

    2011-03-01

    Full Text Available Background: Root canal infection and periapical diseases are caused by bacteria and their products. Long term infection may spread bacteria throughout the root canal system. Apical periodontitis caused by infectious microbe that persistent in root canals can cause radiographic and histopathology periapical changes. Chemomechanical preparation and intracanal dressing then are recommended to be conducted and used in between visits to eliminate microbes in root canals. Calcium hydroxide (Ca(OH2 can be used as intracanal dressing since it can be used as musical physical defense barrier to eliminate re-infection in root canal and to disturb nutrition supply for bacterial development. Purpose: The aim of this study is observe the effectiveness of Ca(OH2 in treating endodontic teeth with apical periodontitis. Cases: Case 1 and 3 are about patients whose left posterior mandibular teeth had spontaneous intermittent pain. Case 2 is about a patient whose left posterior maxillary teeth had gingival abscess and fracture history. Based on the radiographic examination, it was known that the filling of root canal was incomplete and there was radiolucency in the apical area. Case management: The cases were treated with triad endodontics, which involves preparation, disinfection by using 2.5% NaOCl as irrigation substance and calcium hydroxide as intracanal dressing, and then the filling of root canal with gutta percha and endomethasone root canal cement. Evaluations were conducted one month, 12 months, and 24 months after the treatment. Conclusion: Calcium hydroxide is effective to be used as intracanal dressing in apical periodontitis cases.Latar belakang: Infeksi saluran akar dan penyakit periapeks disebabkan oleh mikroba dan produknya. Infeksi yang berlangsung lama memungkinkan bakteri masuk ke dalam seluruh sistem saluran akar. Periodontitis apikal disebabkan oleh infeksi persisten mikroba di dalam sistem saluran akar disertai perubahan radiografik dan

  13. A restricted set of apical proteins recycle through the trans-Golgi network in MDCK cells.

    OpenAIRE

    Brändli, A W; Simons, K

    1989-01-01

    Sorting of newly synthesized proteins destined for the apical plasma membrane takes place in the trans-Golgi network (TGN) in MDCK cells. This process is most likely receptor mediated and requires components that recycle between both compartments. We have developed an assay to detect apical proteins that recycle through the sialyltransferase-containing TGN. Cell surface glycoproteins were exogalactosylated apically using a mutant cell line derived from MDCK, MDCKII-RCAr. The mutant exhibits i...

  14. Apical ammonium inhibition of cAMP-stimulated secretion in T84 cells is bicarbonate dependent.

    Science.gov (United States)

    Worrell, Roger T; Best, Alison; Crawford, Oscar R; Xu, Jie; Soleimani, Manoocher; Matthews, Jeffrey B

    2005-10-01

    Normal human colonic luminal (NH(4)(+)) concentration ([NH(4)(+)]) ranges from approximately 10 to 100 mM. However, the nature of the effects of NH(4)(+) on transport, as well as NH(4)(+) transport itself, in colonic epithelium is poorly understood. We elucidate here the effects of apical NH(4)(+) on cAMP-stimulated Cl(-) secretion in colonic T84 cells. In HEPES-buffered solutions, 10 mM apical NH(4)(+) had no significant effect on cAMP-stimulated current. In contrast, 10 mM apical NH(4)(+) reduced current within 5 min to 61 +/- 4% in the presence of 25 mM HCO(3)(-). Current inhibition was not simply due to an increase in extracellular K(+)-like cations, in that the current magnitude was 95 +/- 5% with 10 mM apical K(+) and 46 +/- 3% with 10 mM apical NH(4)(+) relative to that with 5 mM apical K(+). We previously demonstrated that inhibition of Cl(-) secretion by basolateral NH(4)(+) occurs in HCO(3)(-)-free conditions and exhibits anomalous mole fraction behavior. In contrast, apical NH(4)(+) inhibition of current in HCO(3)(-) buffer did not show anomalous mole fraction behavior and followed the absolute [NH(4)(+)] in K(+)-NH(4)(+) mixtures, where K(+) concentration + [NH(4)(+)] = 10 mM. The apical NH(4)(+) inhibitory effect was not prevented by 100 microM methazolamide, suggesting no role for apical carbonic anhydrase. However, apical NH(4)(+) inhibition of current was prevented by 10 min of pretreatment of the apical surface with 500 microM DIDS, 100 microM 4,4'-dinitrostilbene-2,2'-disulfonic acid (DNDS), or 25 microM niflumic acid, suggesting a role for NH(4)(+) action through an apical anion exchanger. mRNA and protein for the apical anion exchangers SLC26A3 [downregulated in adenoma (DRA)] and SLC26A6 [putative anion transporter (PAT1)] were detected in T84 cells by RT-PCR and Northern and Western blots. DRA and PAT1 appear to associate with CFTR in the apical membrane. We conclude that the HCO(3)(-) dependence of apical NH(4)(+) inhibition of secretion is

  15. Prognostic factors in apical surgery with root-end filling: a meta-analysis

    DEFF Research Database (Denmark)

    von Arx, Thomas; Peñarrocha, Miguel; Jensen, Storgård

    2010-01-01

    Apical surgery has seen continuous development with regard to equipment and surgical technique. However, there is still a shortage of evidence-based information regarding healing determinants. The objective of this meta-analysis was to review clinical articles on apical surgery with root-end fill......Apical surgery has seen continuous development with regard to equipment and surgical technique. However, there is still a shortage of evidence-based information regarding healing determinants. The objective of this meta-analysis was to review clinical articles on apical surgery with root...

  16. com e sem remoção do delta apical

    Directory of Open Access Journals (Sweden)

    Guilherme Mello

    2006-01-01

    Full Text Available This study evaluated the apex cut and apical fusion by Nd:YAG laser at apical surgery. 24 human canines were endodontic treated and randomly divided into two groups. In A group the apicoectomy was performed at 90 degrees and 3mm from the apex extreme; in B group the apex was kept. Both groups were irradiated by Nd:YAG laser (10Hz, 150mJ, 60s. The results showed less infiltration to A group (p<0,001. When Nd:YAG laser apical fusion after apicoectomy were performed at the parameters of this study, best apical isolation is obtained.

  17. Potential of Translationally Controlled Tumor Protein-Derived Protein Transduction Domains as Antigen Carriers for Nasal Vaccine Delivery.

    Science.gov (United States)

    Bae, Hae-Duck; Lee, Joohyun; Jin, Xing-Hai; Lee, Kyunglim

    2016-09-01

    Nasal vaccination offers a promising alternative to intramuscular (i.m.) vaccination because it can induce both mucosal and systemic immunity. However, its major drawback is poor absorption of large antigens in the nasal epithelium. Protein transduction domains (PTDs), also called cell-penetrating peptides, have been proposed as vehicles for nasal delivery of therapeutic peptides and proteins. Here, we evaluated the potential of a mutant PTD derived from translationally controlled tumor protein (designated TCTP-PTD 13) as an antigen carrier for nasal vaccines. We first compared the l- and d-forms of TCTP-PTD 13 isomers (l- or d-TCTP-PTD 13) as antigen carriers. Studies in mice demonstrated that nasally administered mixtures of the model antigen ovalbumin (OVA) and d-TCTP-PTD 13 induced higher plasma IgG titers and secretory IgA levels in nasal washes than nasally administered OVA alone, OVA/l-TCTP-PTD 13, or i.m.-injected OVA. Plasma IgG subclass responses (IgG1 and IgG2a) of mice nasally administered OVA/d-TCTP-PTD 13 showed that the predominant IgG subclass was IgG1, indicating a Th2-biased immune response. We also used synthetic CpG oligonucleotides (CpG) as a Th1 immune response-inducing adjuvant. Nasally administered CpG plus OVA/d-TCTP-PTD 13 was superior in eliciting systemic and mucosal immune responses compared to those induced by nasally administered OVA/d-TCTP-PTD 13. Furthermore, the OVA/CpG/d-TCTP-PTD 13 combination skewed IgG1 and IgG2a profiles of humoral immune responses toward a Th1 profile. These findings suggest that TCTP-derived PTD is a suitable vehicle to efficiently carry antigens and to induce more powerful antigen-specific immune responses and a more balanced Th1/Th2 response when combined with a DNA adjuvant. PMID:27454469

  18. 云环境下跨域RBAC模型中的风险研究%Research on Risk of RBAC Cross-domain Access Control Model

    Institute of Scientific and Technical Information of China (English)

    魏利利; 袁家斌

    2012-01-01

    从云环境下跨域资源访问的安全需求出发,结合现有系统采用访问控制模型的现状,在RBAC模型的基础上,引入风险管理机制,将风险游标的概念扩充到访问发起域中,增强了跨域访问的安全性.在交互的双方中引入时效性约束,将访问时间与风险等级挂钩,从而实现细粒度基于风险的跨域访问控制.同时为域中每个节点设置跨域访问次数阈值,限定节点申请跨域访问的频率,避免了集中恶意行为的发生.通过设置标识位的方法,限制管理节点对历史记录的访问,实现对历史记录的隐私保护.%From the view of security requirements on cross-domain resource, combining with the current situation of the access control model in existed system, we propose a new cross-domain access control model with risk mechanism. This model imports risk management to RBAC model. Not only uses it in the required domain, but also extends the risk cursor to the domain which starts the requirement. This risk cursor mechanism enhances the security of cross domain requirement. In addition, the model also imports timeline in each domain which involved in the requirement. The timeline binds with the risk level in order to realize the granule of the cross-domain access control. It is determined by the human beings according to the experience. The nodes which require longer time may involve higher risk. With risk and timeline mechanism, a fine-grained authorization mechanism is enabled. This new model also set threshold of visiting time to limit the frequency of the requirement, in order to restrict the frequency of the requirement. It will a-void the happening of the centralized malicious behavior. Use 0 or 1 to mark which resource the management node can see. Through the method of restrictions on history records management node visit, this model realizes privacy protection on the historical records.

  19. Time-Domain Simulations of Aerodynamic Forces on Three-Dimensional Configurations, Unstable Aeroelastic Responses, and Control by Neural Network Systems

    OpenAIRE

    Wang, Zhicun

    2004-01-01

    The nonlinear interactions between aerodynamic forces and wing structures are numerically investigated as integrated dynamic systems, including structural models, aerodynamics, and control systems, in the time domain. An elastic beam model coupled with rigid-body rotation is developed for the wing structure, and the natural frequencies and mode shapes are found by the finite-element method. A general unsteady vortex-lattice method is used to provide aerodynamic forces. This method is verified...

  20. Cryopreservation of Galanthus elwesii Hook. apical meristems by droplet vitrification.

    Science.gov (United States)

    Maslanka, M; Panis, B; Bach, A

    2013-01-01

    The aim of this study was to develop an efficient cryopreservation protocol for the geophyte giant snowdrop (Galanthus elwesii Hook.) that guarantees a high rate of survival and plant regeneration after cryopreservation. The excised apical meristems were obtained from cultures of in vitro grown bulb scales. Using a vitrification procedure and optimizing the duration of the exposure to the loading solution (LS), meristem post-rewarm survival rates higher than 90 percent were achieved. Also regrowth percentages were very high, ranging from 87 to 91 percent. After optimizing the time of exposure to the plant vitrification solution (PVS2), the survival rate was between 83 and 97 percent. During post-rewarm regeneration, good growth recovery was as high as 76 percent; however, hyperhydration and callusing were also observed. The results demonstrate that cryopreservation of Galanthus elwesii germplasm seems to be feasible. PMID:23435704

  1. Case of cheilitis granulomatosa associated with apical periodontitis.

    Science.gov (United States)

    Kawakami, Tomoko; Fukai, Kazuyoshi; Sowa, Junko; Ishii, Masamitsu; Teramae, Hiroyuki; Kanazawa, Koutetsu

    2008-02-01

    The etiology of cheilitis granulomatosa is unknown. In some cases, rapid improvement and/or complete elimination of swelling of the lips after dental treatment has been reported. Here, we describe another case of improvement following dental treatment. A 57-year-old woman had developed asymptomatic swelling of the lower lip 2 months previously. Histological examination revealed non-caseous giant cell granulomas. Neither facial nerve palsy nor fissuring of the tongue was present. Patch testing for metal allergy revealed only mild irritation to zinc ion. Although topical corticosteroid ointment and oral tranilast for 4 months were ineffective, rapid and remarkable improvement of the swelling was noted soon after treatment of two lesions of apical periodontitis. Thorough examination for foci of infection is necessary when treating a patient with cheilitis granulomatosa. PMID:18271809

  2. Cryopreservation of Galanthus elwesii Hook. apical meristems by droplet vitrification.

    Science.gov (United States)

    Maslanka, M; Panis, B; Bach, A

    2013-01-01

    The aim of this study was to develop an efficient cryopreservation protocol for the geophyte giant snowdrop (Galanthus elwesii Hook.) that guarantees a high rate of survival and plant regeneration after cryopreservation. The excised apical meristems were obtained from cultures of in vitro grown bulb scales. Using a vitrification procedure and optimizing the duration of the exposure to the loading solution (LS), meristem post-rewarm survival rates higher than 90 percent were achieved. Also regrowth percentages were very high, ranging from 87 to 91 percent. After optimizing the time of exposure to the plant vitrification solution (PVS2), the survival rate was between 83 and 97 percent. During post-rewarm regeneration, good growth recovery was as high as 76 percent; however, hyperhydration and callusing were also observed. The results demonstrate that cryopreservation of Galanthus elwesii germplasm seems to be feasible.

  3. Serious arrhythmias in patients with apical hypertrophic cardiomyopathy

    International Nuclear Information System (INIS)

    We report cases of serious arrhythmias associated with apical hypertrophic cardiomyopathy (AHCM). Thirty-one patients were referred to our institute to undergo further assessment of their AHCM from 1988 to 1999. Three patients with nonsustained ventricular tachycardia demonstrated an 123I-MIBG regional reduction in the tracer uptake. In two patients with ventricular fibrillation (VF), the findings from 123I-MIBG imaging revealed regional sympathetic denervation in the inferior and lateral regions. Electrophysiologic study demonstrated reproducible induction of VF in aborted sudden death and presyncopal patients, resulting in the need for an implantable defibrillator device and amiodarone in each patient. Patients with refractory atrial fibrillation with a rapid ventricular response suffered from serious congestive heart failure. A prudent assessment and strategy in patients with this disease would be indispensable in avoiding a disastrous outcome. (author)

  4. Serious arrhythmias in patients with apical hypertrophic cardiomyopathy

    Energy Technology Data Exchange (ETDEWEB)

    Okishige, Kaoru; Sasano, Tetsuo; Yano, Kei; Azegami, Kouji; Suzuki, Kou; Itoh, Kuniyasu [Yokohama Red Cross Hospital (Japan)

    2001-05-01

    We report cases of serious arrhythmias associated with apical hypertrophic cardiomyopathy (AHCM). Thirty-one patients were referred to our institute to undergo further assessment of their AHCM from 1988 to 1999. Three patients with nonsustained ventricular tachycardia demonstrated an {sup 123}I-MIBG regional reduction in the tracer uptake. In two patients with ventricular fibrillation (VF), the findings from {sup 123}I-MIBG imaging revealed regional sympathetic denervation in the inferior and lateral regions. Electrophysiologic study demonstrated reproducible induction of VF in aborted sudden death and presyncopal patients, resulting in the need for an implantable defibrillator device and amiodarone in each patient. Patients with refractory atrial fibrillation with a rapid ventricular response suffered from serious congestive heart failure. A prudent assessment and strategy in patients with this disease would be indispensable in avoiding a disastrous outcome. (author)

  5. Oral microbiota species in acute apical endodontic abscesses

    Science.gov (United States)

    George, Noelle; Flamiatos, Erin; Kawasaki, Kellie; Kim, Namgu; Carriere, Charles; Phan, Brian; Joseph, Raphael; Strauss, Shay; Kohli, Richie; Choi, Dongseok; Craig Baumgartner, J.; Sedgley, Christine; Maier, Tom; Machida, Curtis A.

    2016-01-01

    Background and objectives Acute apical abscesses are serious endodontic diseases resulting from pulpal infection with opportunistic oral microorganisms. The objective of this study was to identify and compare the oral microbiota in patients (N=18) exhibiting acute apical abscesses, originating from the demographic region in Portland, Oregon. The study hypothesis is that abscesses obtained from this demographic region may contain unique microorganisms not identified in specimens from other regions. Design Endodontic abscesses were sampled from patients at the Oregon Health & Science University (OHSU) School of Dentistry. DNA from abscess specimens was subjected to polymerase chain reaction amplification using 16S rRNA gene-specific primers and Cy3-dCTP labeling. Labeled DNA was then applied to microbial microarrays (280 species) generated by the Human Oral Microbial Identification Microarray Laboratory (Forsyth Institute, Cambridge, MA). Results The most prevalent microorganisms, found across multiple abscess specimens, include Fusobacterium nucleatum, Parvimonas micra, Megasphaera species clone CS025, Prevotella multisaccharivorax, Atopobium rimae, and Porphyromonas endodontalis. The most abundant microorganisms, found in highest numbers within individual abscesses, include F. nucleatum, P. micra, Streptococcus Cluster III, Solobacterium moorei, Streptococcus constellatus, and Porphyromonas endodontalis. Strong bacterial associations were identified between Prevotella multisaccharivorax, Acidaminococcaceae species clone DM071, Megasphaera species clone CS025, Actinomyces species clone EP053, and Streptococcus cristatus (all with Spearman coefficients >0.9). Conclusions Cultivable and uncultivable bacterial species have been identified in endodontic abscesses obtained from the Portland, Oregon demographic region, and taxa identifications correlated well with other published studies, with the exception of Treponema and Streptococcus cristae, which were not commonly

  6. Aquaporin-2: COOH terminus is necessary but not sufficient for routing to the apical membrane.

    NARCIS (Netherlands)

    Deen, P.M.T.; Balkom, B.W.M. van; Savelkoul, P.J.M.; Kamsteeg, E.J.; Raak, M.M.J.P. van; Jennings, M.L.; Muth, T.R.; Rajendran, V.; Caplan, M.J.

    2002-01-01

    Renal regulation of mammalian water homeostasis is mediated by the aquaporin-1 (AQP1) water channel, which is expressed in the apical and basolateral membranes of proximal tubules and descending limbs of Henle, and aquaporin-2 (AQP2), which is redistributed from intracellular vesicles to the apical

  7. Mechanisms of apical-basal axis orientation and epithelial lumen positioning

    NARCIS (Netherlands)

    Overeem, Arend W.; Bryant, David M.; van IJzendoorn, Sven C. D.

    2015-01-01

    In epithelial cells, the polarized orientation of the apical-basal axis determines the position of the apical lumen and, thereby, the collective tubular tissue architecture. From recent studies employing 3D cell cultures, animal models, and patient material, a model is emerging in which the orientat

  8. Developmental Corneal Innervation: Interactions between Nerves and Specialized Apical Corneal Epithelial Cells

    OpenAIRE

    Kubilus, James K.; Linsenmayer, Thomas F.

    2010-01-01

    During developmental innervation of the chicken cornea, nerves interact with apical corneal epithelial cells to form synapse-like structures. In addition, these apical epithelial cells express class III β-tubulin, an isoform of β-tubulin generally thought to be neuron specific.

  9. Approximate Controllability of a Reaction-Diffusion System with a Cross-Diffusion Matrix and Fractional Derivatives on Bounded Domains

    OpenAIRE

    Badraoui Salah

    2010-01-01

    We study the following reaction-diffusion system with a cross-diffusion matrix and fractional derivatives in , in , on , , in where is a smooth bounded domain, , the diffusion matrix has semisimple and positive eigenvalues , , is an open nonempty set, and is the characteristic function of . Specifically, we prove that under some conditions over the coefficients , the semigroup generated by the linear operator of the system is exponentially stable, and under other c...

  10. Conformational Dynamics of the Focal Adhesion Targeting Domain Control Specific Functions of Focal Adhesion Kinase in Cells

    KAUST Repository

    Kadaré, Gress

    2015-01-02

    Focal adhesion (FA) kinase (FAK) regulates cell survival and motility by transducing signals from membrane receptors. The C-terminal FA targeting (FAT) domain of FAK fulfils multiple functions, including recruitment to FAs through paxillin binding. Phosphorylation of FAT on Tyr925 facilitates FA disassembly and connects to the MAPK pathway through Grb2 association, but requires dissociation of the first helix (H1) of the four-helix bundle of FAT. We investigated the importance of H1 opening in cells by comparing the properties of FAK molecules containing wild-type or mutated FAT with impaired or facilitated H1 openings. These mutations did not alter the activation of FAK, but selectively affected its cellular functions, including self-association, Tyr925 phosphorylation, paxillin binding, and FA targeting and turnover. Phosphorylation of Tyr861, located between the kinase and FAT domains, was also enhanced by the mutation that opened the FAT bundle. Similarly phosphorylation of Ser910 by ERK in response to bombesin was increased by FAT opening. Although FAK molecules with the mutation favoring FAT opening were poorly recruited at FAs, they efficiently restored FA turnover and cell shape in FAK-deficient cells. In contrast, the mutation preventing H1 opening markedly impaired FAK function. Our data support the biological importance of conformational dynamics of the FAT domain and its functional interactions with other parts of the molecule.

  11. VEGFR-2 reduces while combined VEGFR-2 and -3 signaling increases inflammation in apical periodontitis

    Science.gov (United States)

    Virtej, Anca; Papadakou, Panagiota; Sasaki, Hajime; Bletsa, Athanasia; Berggreen, Ellen

    2016-01-01

    Background In apical periodontitis, oral pathogens provoke an inflammatory response in the apical area that induces bone resorptive lesions. In inflammation, angio- and lymphangiogenesis take place. Vascular endothelial growth factors (VEGFs) and their receptors (VEGFRs) are key players in these processes and are expressed in immune cells and endothelial cells in the lesions. Objective We aimed at testing the role of VEGFR-2 and -3 in periapical lesion development and investigated their role in lymphangiogenesis in the draining lymph nodes. Design We induced lesions by pulp exposure in the lower first molars of C57BL/6 mice. The mice received IgG injections or blocking antibodies against VEGFR-2 (anti-R2), VEGFR-3 (anti-R3), or combined VEGFR-2 and -3, starting on day 0 until day 10 or 21 post-exposure. Results Lesions developed faster in the anti-R2 and anti-R3 group than in the control and anti-R2/R3 groups. In the anti-R2 group, a strong inflammatory response was found expressed as increased number of neutrophils and osteoclasts. A decreased level of pro-inflammatory cytokines was found in the anti-R2/R3 group. Lymphangiogenesis in the draining lymph nodes was inhibited after blocking of VEGFR-2 and/or -3, while the largest lymph node size was seen after anti-R2 treatment. Conclusions We demonstrate an anti-inflammatory effect of VEGFR-2 signaling in periapical lesions which seems to involve neutrophil regulation and is independent of angiogenesis. Combined signaling of VEGFR-2 and -3 has a pro-inflammatory effect. Lymph node lymphangiogenesis is promoted through activation of VEGFR-2 and/or VEGFR-3. PMID:27650043

  12. Assessment of Root Morphology and Apices of First and Second Maxillary Molars in Tehran Population

    Directory of Open Access Journals (Sweden)

    Mandana Naseri

    2015-12-01

    Full Text Available Introduction: Objective: This study aimed to assess the possible variations in root canal anatomy and topography of the apices of first and second maxillary molars. Materials and methods: A total of 67 first and second maxillary permanent molars were collected. Access cavity was prepared and 2% methylene blue was injected. The teeth were demineralized by 5% nitric acid and cleared with methyl salicylate. Specimens were evaluated under stereomicroscopy and analyzed using the sample t-test. Results: Based on Vertucci’s classification, the mesiobuccal root of maxillary first molars was type I in 87.5% and type IV in 12.5% of the cases. The mesiobuccal root of second maxillary molars was type I in 60%, type II in 8.6%, type IV in 25.7% and type V in 5.7% of cases. In maxillary first and second molars, the distobuccal and palatal roots were type I in 100% of the cases. The distance of the apical constriction from the apical foramen was 0.21±0.09 mm, the distance from the apical constriction tothe anatomic apex was 0.44±0.19 mm and the distance of the apical foramen from the anatomic apex was 0.15±0.15 mm. The mean percentage of delta prevalence was 3.2% in both teeth. Conclusion: The mean distance of the apical foramen and apical constriction from the anatomic apex was less than 0.6 and 1.2 mm, respectively. In maxillary first and second molars, the mean distance of the apical constriction from the apical foramen and anatomic apex was 0.21 and 0.44, respectively and the mean distance of the apical foramen from the anatomic apex was 0.15 mm

  13. Evaluation of apical subtype of hypertrophic cardiomyopathy using cardiac magnetic resonance imaging with gadolinium enhancement.

    Science.gov (United States)

    Kebed, Kalie Y; Al Adham, Raed I; Bishu, Kalkidan; Askew, J Wells; Klarich, Kyle W; Araoz, Philip A; Foley, Thomas A; Glockner, James F; Nishimura, Rick A; Anavekar, Nandan S

    2014-09-01

    Apical hypertrophic cardiomyopathy (HC) is an uncommon variant of HC. We sought to characterize cardiac magnetic resonance imaging (MRI) findings among apical HC patients. This was a retrospective review of consecutive patients with a diagnosis of apical HC who underwent cardiac MRI examinations at the Mayo Clinic (Rochester, MN) from August 1999 to October 2011. Clinical and demographic data at the time of cardiac MRI study were abstracted. Cardiac MRI study and 2-dimensional echocardiograms performed within 6 months of the cardiac MRI were reviewed; 96 patients with apical HC underwent cardiac MRI examinations. LV end-diastolic and end-systolic volumes were 130.7 ± 39.1 ml and 44.2 ± 20.9 ml, respectively. Maximum LV thickness was 19 ± 5 mm. Hypertrophy extended beyond the apex into other segments in 57 (59.4%) patients. Obstructive physiology was seen in 12 (12.5%) and was more common in the mixed apical phenotype than the pure apical (19.3 vs 2.6%, p = 0.02). Apical pouches were noted in 39 (40.6%) patients. Late gadolinium enhancement (LGE) was present in 70 (74.5%) patients. LGE was associated with severe symptoms and increased maximal LV wall thickness. In conclusion, cardiac MRI is well suited for studying the apical form of HC because of difficulty imaging the cardiac apex with standard echocardiography. Cardiac MRI is uniquely suited to delineate the presence or absence of an apical pouch and abnormal myocardial LGE that may have implications in the natural history of apical HM. In particular, the presence of abnormal LGE is associated with clinical symptoms and increased wall thickness. PMID:25037678

  14. Randomized controlled clinical studies of Light-Speed LSX system in single-visit and two-visit root canal treatment of chronic apical periodontitis%Light-Speed LSX系统一次法和两次法治疗慢性根尖周炎的临床研究

    Institute of Scientific and Technical Information of China (English)

    吴志国; 杜红保; 李斌; 吴翠柳

    2015-01-01

    目的:采用Light-Speed LSX根管预备系统对慢性根尖周炎患者采用一次法根管治疗和两次法根管治疗,评估术后2年随访结果,比较二者治疗成功率。方法300例上下颌慢性根尖周炎患牙随机分为2组,A组为一次性完成根管治疗, B组分次完成根管预备和根管充填,所有组内患牙均使用Light-Speed LSX根管预备器械进行根管预备,评价患牙术后2年的临床和影像学表现。结果采用Light-Speed LSX根管预备系统进行根管预备,一次法组138例(93.88%)治愈,两次法组122例(89.05%)治愈;疗效不确定的一次法组5例(3.40%),两次法组9例(6.57%);治疗失败的一次法组4例(2.72%),两次法组6例(4.38%)。两组治疗成功率的比较采用卡方检验,结果显示两组治疗成功率无统计学差异(P>0.05)。结论采用Light-Speed LSX根管预备系统对慢性根尖周炎患者采用一次法根管治疗和两次法根管治疗成功率无差异。%Objective To evaluate and compare the outcomes of Light-Speed LSX systems in single-visit and two-visit root canal treatment of patients with chronic apical periodontitis after a 2-year follow-up. Methods 300 maxillary and mandibular teeth with chro-nic apical periodontitis were randomly assigned into two groups. While the teeth of patients in group A were obturated,those in group B were temporarily sealed and obturated one week later. All canals were enlarged with Light-speedLSX root canal instruments. The healing results were clinically and radiographically evaluated 2 years after the operation. Results Of the 300 treated teeth,138 of 147 teeth (93. 88%) in the A group were healed compared with 122 of 137 teeth (89. 05%) in the B group,curative effects of 5 cases (3. 40%) in the A group were classified as uncertain compared with 9 cases (6. 57%) in the B group;4 cases (2. 72%) in the A group and 6 cases (4. 38%) in the B group were classified as not healed. Chi-square test was used to compare the

  15. Light-Speed LSX系统一次法和两次法治疗慢性根尖周炎的临床研究%Randomized controlled clinical studies of Light-Speed LSX system in single-visit and two-visit root canal treatment of chronic apical periodontitis

    Institute of Scientific and Technical Information of China (English)

    吴志国; 杜红保; 李斌; 吴翠柳

    2015-01-01

    目的:采用Light-Speed LSX根管预备系统对慢性根尖周炎患者采用一次法根管治疗和两次法根管治疗,评估术后2年随访结果,比较二者治疗成功率。方法300例上下颌慢性根尖周炎患牙随机分为2组,A组为一次性完成根管治疗, B组分次完成根管预备和根管充填,所有组内患牙均使用Light-Speed LSX根管预备器械进行根管预备,评价患牙术后2年的临床和影像学表现。结果采用Light-Speed LSX根管预备系统进行根管预备,一次法组138例(93.88%)治愈,两次法组122例(89.05%)治愈;疗效不确定的一次法组5例(3.40%),两次法组9例(6.57%);治疗失败的一次法组4例(2.72%),两次法组6例(4.38%)。两组治疗成功率的比较采用卡方检验,结果显示两组治疗成功率无统计学差异(P>0.05)。结论采用Light-Speed LSX根管预备系统对慢性根尖周炎患者采用一次法根管治疗和两次法根管治疗成功率无差异。%Objective To evaluate and compare the outcomes of Light-Speed LSX systems in single-visit and two-visit root canal treatment of patients with chronic apical periodontitis after a 2-year follow-up. Methods 300 maxillary and mandibular teeth with chro-nic apical periodontitis were randomly assigned into two groups. While the teeth of patients in group A were obturated,those in group B were temporarily sealed and obturated one week later. All canals were enlarged with Light-speedLSX root canal instruments. The healing results were clinically and radiographically evaluated 2 years after the operation. Results Of the 300 treated teeth,138 of 147 teeth (93. 88%) in the A group were healed compared with 122 of 137 teeth (89. 05%) in the B group,curative effects of 5 cases (3. 40%) in the A group were classified as uncertain compared with 9 cases (6. 57%) in the B group;4 cases (2. 72%) in the A group and 6 cases (4. 38%) in the B group were classified as not healed. Chi-square test was used to compare the

  16. Comparison of Apical Sealing Ability of Lateral Condensation Technique in Room and Body- Simulated Temperatures (An in vitro study

    Directory of Open Access Journals (Sweden)

    Sobhnamayan F.

    2013-03-01

    Full Text Available Statement of Problem: Studies reported that nearly 60% of endodontic failures have been attributed to inadequate obturation of the root canal system. Thus, complete obturation of the root canal system and proper apical seal are essential elements in the long-term success of root canal treatment.Purpose: This study aimed to compare the apical seal of lateral condensation tech-nique in the room and in body- simulated temperature.Materials and Method: In this experimental study, 70 extracted, single- rooted, human premolar teeth were instrumented and divided up into four groups. All tooth’s canals were obturated by lateral condensation technique except the teeth in the positive control group. Group 1and 2, each with 30 teeth, were obturated in the room and intracanal temperature respectively. The other two groups were positive and negative control group each with 5 teeth. All groups except negative control were covered by two layers of nail polish. Then linear dye penetration was evaluated with a stereomicroscope. Data was analyzed with student-t test and also Kolmogorov- Smirnov Goodness- of- Fit test to make sure of data. Results: Results showed that dye penetration in group one (obturation in room temperature was 0.6mm more than group 2 (obturation in simulated-body temperature although this was not statistically significant (p> 0.05.Conclusion: Under the condition of this invitro study, apical sealing ability was better in the body-simulated temperature than the room temperature, although it was not statistically significant.

  17. Hinge-loop mutation can be used to control 3D domain swapping and amyloidogenesis of human cystatin C.

    Science.gov (United States)

    Orlikowska, Marta; Jankowska, Elżbieta; Kołodziejczyk, Robert; Jaskólski, Mariusz; Szymańska, Aneta

    2011-02-01

    Cystatins are natural inhibitors of cysteine proteases, enzymes that are widely distributed in animals, plants, and microorganisms. Human cystatin C (hCC) has been also recognized as an aggregating protein directly involved in the formation of pathological amyloid fibrils, and these amyloidogenic properties greatly increase in a naturally occurring L68Q hCC variant. For a long time only dimeric structure of wild-type hCC has been known. The dimer is created through 3D domain swapping process, in which two parts of the cystatin structure become separated from each other and next exchanged between two molecules. Important role in the domain swapping plays the L1 loop, which connects the exchanging segments and, upon dimerization, transforms from a β-turn into a part of a long β-strand. In the very recently published first monomeric structure of human cystatin C (hCC-stab1), dimerization was abrogated due to clasping of the β-strands from the swapping domains by an engineered disulfide bridge. We have designed and constructed another mutated cystatin C with the smallest possible structural intervention, that is a single-point mutation replacing hydrophobic V57 from the L1 loop by polar asparagine, known as a stabilizer of a β-turn motif. V57N hCC mutant occurred to be stable in its monomeric form and crystallized as a monomer, revealing typical cystatin fold with a five-stranded antiparallel β-sheet wrapped around an α-helix. Here we report a 2.04 Å resolution crystal structure of V57N hCC and discuss the architecture of the protein in comparison to chicken cystatin, hCC-stab1 and dimeric hCC.

  18. Identification of a highly antigenic linear B cell epitope within Plasmodium vivax apical membrane antigen 1 (AMA-1.

    Directory of Open Access Journals (Sweden)

    Lilian Lacerda Bueno

    Full Text Available Apical membrane antigen 1 (AMA-1 is considered to be a major candidate antigen for a malaria vaccine. Previous immunoepidemiological studies of naturally acquired immunity to Plasmodium vivax AMA-1 (PvAMA-1 have shown a higher prevalence of specific antibodies to domain II (DII of AMA-1. In the present study, we confirmed that specific antibody responses from naturally infected individuals were highly reactive to both full-length AMA-1 and DII. Also, we demonstrated a strong association between AMA-1 and DII IgG and IgG subclass responses. We analyzed the primary sequence of PvAMA-1 for B cell linear epitopes co-occurring with intrinsically unstructured/disordered regions (IURs. The B cell epitope comprising the amino acid sequence 290-307 of PvAMA-1 (SASDQPTQYEEEMTDYQK, with the highest prediction scores, was identified in domain II and further selected for chemical synthesis and immunological testing. The antigenicity of the synthetic peptide was identified by serological analysis using sera from P. vivax-infected individuals who were knowingly reactive to the PvAMA-1 ectodomain only, domain II only, or reactive to both antigens. Although the synthetic peptide was recognized by all serum samples specific to domain II, serum with reactivity only to the full-length protein presented 58.3% positivity. Moreover, IgG reactivity against PvAMA-1 and domain II after depletion of specific synthetic peptide antibodies was reduced by 18% and 33% (P = 0.0001 for both, respectively. These results suggest that the linear epitope SASDQPTQYEEEMTDYQK is highly antigenic during natural human infections and is an important antigenic region of the domain II of PvAMA-1, suggesting its possible future use in pre-clinical studies.

  19. "In vitro" evaluation of the apical sealing of root canals obturated with different techniques Avaliação "in vitro" do selamento apical dos canais radiculares em função de diferentes técnicas de obturação

    Directory of Open Access Journals (Sweden)

    Viviane Haiub Brosco

    2003-09-01

    Full Text Available The purpose of this study was to compare the apical sealing of root canals obturated with different techniques. One hundred-six human mandibular incisors were submitted to instrumentation by means of the step-back technique. After instrumentation, one hundred teeth received an impermeable coating on the external surfaces of the crown and root (except for the area nearby the apical foramen. Afterwards, they were divided in five groups containing twenty elements each, according to the obturation technique employed: 1. lateral condensation with Kerr file; 2. continuous wave of condensation technique with System B; 3. thermoplasticized injectable gutta-percha technique with the Ultrafil system; 4. mechanically thermoplasticized gutta-percha with the JS Quick-Fill system and 5. thermoplasticized gutta-percha associated to a master cone with the Microseal system. The six remaining teeth were employed as negative and positive controls. After obturation, the access cavities were sealed and the teeth were immersed in aqueous 2% methylene blue dye for 72 hours at 37ºC. After that, the teeth were longitudinally sectioned and the apical microleakage was evaluated in a stereomicroscope. The Microseal system presented the best apical sealing ability, followed by System B, JS Quick-Fill, Ultrafil and the lateral condensation technique. The statistical analysis of the results demonstrated that: 1. the Microseal system presented an apical sealing similar to System B and better than the other groups; 2. System B presented better apical sealing than the lateral condensation technique, being similar to the other groups; and 3. the lateral condensation, Ultrafil and JS Quick-Fill groups demonstrated similar sealing ability.Este estudo teve como objetivo avaliar o selamento apical de canais radiculares obturados por diferentes técnicas. Cento e seis incisivos inferiores humanos tiveram seus canais instrumentados através da técnica escalonada regressiva. Após a

  20. Comparison of dentinal and apical crack formation caused by four different nickel-titanium rotary and reciprocating systems in large and small canals.

    Science.gov (United States)

    Zhou, Xin; Jiang, Shan; Wang, Xiao; Wang, Shuai; Zhu, Xiaofei; Zhang, Chengfei

    2015-01-01

    This study compared dentinal and apical crack formation after instrumentation with different nickel-titanium systems at two different working lengths (WL) in large and small canals. Two hundred and eighty human teeth were randomly distributed into two control and 12 experimental groups (n=20 each). Large and small canals were instrumented by the WaveOne, Protaper Universal System (PTU), Twisted File (TF), or Twisted File Adaptive (TFA) at 1 mm shorter than canal length (CL-1 mm) or 1 mm beyond apical foreman (CL+1 mm). Horizontal sections were microscopically observed to evaluate the dentinal cracks (only large canals). Scanning electron microscopy images were taken before and after instrumentation to assess apical cracks. All file types caused more apical cracks in small canals than in large canals regardless of the WL. During over-instrumentation (WL=CL+1 mm), the WaveOne and PTU groups developed significantly more dentinal cracks at the 6 and 9 mm sections than the TF and TFA groups.

  1. Janus-faced Sestrin2 controls ROS and mTOR signalling through two separate functional domains

    Science.gov (United States)

    Kim, Hanseong; An, Sojin; Ro, Seung-Hyun; Teixeira, Filipa; Jin Park, Gyeong; Kim, Cheal; Cho, Chun-Seok; Kim, Jeong-Sig; Jakob, Ursula; Hee Lee, Jun; Cho, Uhn-Soo

    2015-11-01

    Sestrins are stress-inducible metabolic regulators with two seemingly unrelated but physiologically important functions: reduction of reactive oxygen species (ROS) and inhibition of the mechanistic target of rapamycin complex 1 (mTORC1). How Sestrins fulfil this dual role has remained elusive so far. Here we report the crystal structure of human Sestrin2 (hSesn2), and show that hSesn2 is twofold pseudo-symmetric with two globular subdomains, which are structurally similar but functionally distinct from each other. While the N-terminal domain (Sesn-A) reduces alkylhydroperoxide radicals through its helix-turn-helix oxidoreductase motif, the C-terminal domain (Sesn-C) modified this motif to accommodate physical interaction with GATOR2 and subsequent inhibition of mTORC1. These findings clarify the molecular mechanism of how Sestrins can attenuate degenerative processes such as aging and diabetes by acting as a simultaneous inhibitor of ROS accumulation and mTORC1 activation.

  2. Carboxyl-terminal receptor domains control the differential dephosphorylation of somatostatin receptors by protein phosphatase 1 isoforms.

    Directory of Open Access Journals (Sweden)

    Andreas Lehmann

    Full Text Available We have recently identified protein phosphatase 1β (PP1β as G protein-coupled receptor (GPCR phosphatase for the sst2 somatostatin receptor using siRNA knockdown screening. By contrast, for the sst5 somatostatin receptor we identified protein phosphatase 1γ (PP1γ as GPCR phosphatase using the same approach. We have also shown that sst2 and sst5 receptors differ substantially in the temporal dynamics of their dephosphorylation and trafficking patterns. Whereas dephosphorylation and recycling of the sst2 receptor requires extended time periods of ∼30 min, dephosphorylation and recycling of the sst5 receptor is completed in less than 10 min. Here, we examined which receptor domains determine the selection of phosphatases for receptor dephosphorylation. We found that generation of tail-swap mutants between sst2 and sst5 was required and sufficient to reverse the patterns of dephosphorylation and trafficking of these two receptors. In fact, siRNA knockdown confirmed that the sst5 receptor carrying the sst2 tail is predominantly dephosphorylated by PP1β, whereas the sst2 receptor carrying the sst5 tail is predominantly dephosphorylated by PP1γ. Thus, the GPCR phosphatase responsible for dephosphorylation of individual somatostatin receptor subtypes is primarily determined by their different carboxyl-terminal receptor domains. This phosphatase specificity has in turn profound consequences for the dephosphorylation dynamics and trafficking patterns of GPCRs.

  3. Evaluation of the distortion rate of panoramic and peri apical radiographs in erupted third molar inclination

    International Nuclear Information System (INIS)

    Panoramic and peri apical radiographs are normally used in impacted third molar teeth surgeries. The aim of the present study was to evaluate and compare the distortion of the erupted third molar teeth on panoramic and peri apical radiographs. Patients and Methods: A total of 44 radiographs were obtained of 22 patients (age range, 18-24 years) referred to the faculty of dentistry for orthodontic treatment. A plaster cast was prepared and panoramic radiography was taken for all patients to plan the orthodontic treatment and peri apical radiography was taken for investigation of tooth structure details. Therefore, a total of 66 views and samples were studied by two methods: 1) Measuring the angle between the longitudinal plane of the third molar and occlusal plane. 2) Measuring the angle between the longitudinal plane of second and third molar. Finally, 132 records were evaluated by one individual. Results: There was no significant statistical difference between the mean position of the third molar on panoramic, peri apical radiographs and the casts. However, measurements of the third molars on peri apical radiographs were slightly closer to the measurements of the casts compared to the panoramic radiographs. Conclusion: Distortion does not have a specific effect on the diagnosis of the position of the third erupted molars by peri apical or panoramic radiographs, though various studies have shown that these radiographs have an amount of distortion and peri apical radiographical distortion is less than that in panoramic radiography.

  4. The fast-recycling receptor Megalin defines the apical recycling pathway of epithelial cells.

    Science.gov (United States)

    Perez Bay, Andres E; Schreiner, Ryan; Benedicto, Ignacio; Paz Marzolo, Maria; Banfelder, Jason; Weinstein, Alan M; Rodriguez-Boulan, Enrique J

    2016-01-01

    The basolateral recycling and transcytotic pathways of epithelial cells were previously defined using markers such as transferrin (TfR) and polymeric IgA (pIgR) receptors. In contrast, our knowledge of the apical recycling pathway remains fragmentary. Here we utilize quantitative live-imaging and mathematical modelling to outline the recycling pathway of Megalin (LRP-2), an apical receptor with key developmental and renal functions, in MDCK cells. We show that, like TfR, Megalin is a long-lived and fast-recycling receptor. Megalin enters polarized MDCK cells through segregated apical sorting endosomes and subsequently intersects the TfR and pIgR pathways at a perinuclear Rab11-negative compartment termed common recycling endosomes (CRE). Whereas TfR recycles to the basolateral membrane from CRE, Megalin, like pIgR, traffics to subapical Rab11-positive apical recycling endosomes (ARE) and reaches the apical membrane in a microtubule- and Rab11-dependent manner. Hence, Megalin defines the apical recycling pathway of epithelia, with CRE as its apical sorting station.

  5. Variability interexaminer of chronic apical periodontitis diagnostics in panoramic radiographs

    International Nuclear Information System (INIS)

    The accuracy of radiological diagnosis of Apical Periodontitis (AP) is reported between examiners with differents levels of clinical experience using panoramic radiographs. 1032 teeth in 41 panoramic radiographs have been diagnosed. The evaluation of the x-rays and radiological diagnosis is performed by three independent dentists for AP to each tooth. The teeth have presented without radiological signs of AP in 96.6%. The number of teeth classified with an uncertain diagnosis of AP at the has been inversely proportional to the number of years of experience of the examiner. The examiner A has been used as a reference and compared the diagnoses of other examiners.The percentage agreement for all teeth was 95% for examiner B and 94% for examiner C. Kappa for all has been of 0.44 for examiner B and 0.43 for examiner C. The different categories were analyzed separately, the inferior teeth and the anterior teeth have obtained the best results. The level of clinical experience of the examiner has been indifferent in the diagnosis of AP in panoramic radiographs; however, it is important experience in the number of radiographs extras that will be needed to give a radiological diagnosis definitive. The panoramic radiographs were reliable diagnostic tools for AP. (author)

  6. Emergence of an Apical Epithelial Cell Surface In Vivo.

    Science.gov (United States)

    Sedzinski, Jakub; Hannezo, Edouard; Tu, Fan; Biro, Maté; Wallingford, John B

    2016-01-11

    Epithelial sheets are crucial components of all metazoan animals, enclosing organs and protecting the animal from its environment. Epithelial homeostasis poses unique challenges, as addition of new cells and loss of old cells must be achieved without disrupting the fluid-tight barrier and apicobasal polarity of the epithelium. Several studies have identified cell biological mechanisms underlying extrusion of cells from epithelia, but far less is known of the converse mechanism by which new cells are added. Here, we combine molecular, pharmacological, and laser-dissection experiments with theoretical modeling to characterize forces driving emergence of an apical surface as single nascent cells are added to a vertebrate epithelium in vivo. We find that this process involves the interplay between cell-autonomous actin-generated pushing forces in the emerging cell and mechanical properties of neighboring cells. Our findings define the forces driving this cell behavior, contributing to a more comprehensive understanding of epithelial homeostasis. PMID:26766441

  7. Estimating damping effectiveness of BPA`s thyristor controlled series capacitor by applying time and frequency domain methods to measured response

    Energy Technology Data Exchange (ETDEWEB)

    Trudnowski, D.J.; Donnelly, M.K.; Hauer, J.F. [Pacific Northwest Lab., Richland, WA (United States)

    1996-05-01

    Recently, a 500-kV thyristor controlled series capacitor (TCSC) was installed in the Bonneville Power Administration system in the northwestern US. Extensive field testing has included modulation experiments to determine the effect of the TCSC on low-frequency oscillations. This paper discusses modulation procedures, analysis methods, and results for estimating the damping effectiveness of the TCSC. Modulation methods include driving the TCSC with step and random noise, and analysis techniques include time (Prony analysis) and frequency-domain identification. Results indicate that: (1) the TCSC can have significant impact on system dynamics; and (2) under a very small feedback gain, the TCSC provides measurable added damping.

  8. Estimating damping effectiveness of BPA`s thyristor controlled series capacitor by applying time and frequency domain methods to measured response

    Energy Technology Data Exchange (ETDEWEB)

    Trudnowski, D.J.; Donnelly, M.K.; Hauer, J.F.

    1995-07-01

    Recently, a 500-kV thyristor controlled series capacitor (TCSC) was installed in the Bonneville Power Administration system in the northwestern United States. Extensive field testing has included modulation experiments to determine the effect of the TCSC on low- frequency procedures, analysis methods, and results for estimating the damping effectiveness of the TCSC. Modulation methods include driving the TCSC with step and random noise, and analysis techniques include time (Prony analysis) and frequency-domain identification. Results indicate that: (1) the TCSC can have significant impact on system dynamics; and (2) under a very small feedback gain, the TCSC provides measurable added damping.

  9. The RafC1 cysteine-rich domain contains multiple distinct regulatory epitopes which control Ras-dependent Raf activation.

    Science.gov (United States)

    Daub, M; Jöckel, J; Quack, T; Weber, C K; Schmitz, F; Rapp, U R; Wittinghofer, A; Block, C

    1998-11-01

    Activation of c-Raf-1 (referred to as Raf) by Ras is a pivotal step in mitogenic signaling. Raf activation is initiated by binding of Ras to the regulatory N terminus of Raf. While Ras binding to residues 51 to 131 is well understood, the role of the RafC1 cysteine-rich domain comprising residues 139 to 184 has remained elusive. To resolve the function of the RafC1 domain, we have performed an exhaustive surface scanning mutagenesis. In our study, we defined a high-resolution map of multiple distinct functional epitopes within RafC1 that are required for both negative control of the kinase and the positive function of the protein. Activating mutations in three different epitopes enhanced Ras-dependent Raf activation, while only some of these mutations markedly increased Raf basal activity. One contiguous inhibitory epitope consisting of S177, T182, and M183 clearly contributed to Ras-Raf binding energy and represents the putative Ras binding site of the RafC1 domain. The effects of all RafC1 mutations on Ras binding and Raf activation were independent of Ras lipid modification. The inhibitory mutation L160A is localized to a position analogous to the phorbol ester binding site in the protein kinase C C1 domain, suggesting a function in cofactor binding. Complete inhibition of Ras-dependent Raf activation was achieved by combining mutations K144A and L160A, which clearly demonstrates an absolute requirement for correct RafC1 function in Ras-dependent Raf activation.

  10. Obturating teeth with wide open apices using mineral trioxide aggregate: a case report.

    Science.gov (United States)

    Levenstein, H

    2002-07-01

    The conventional approach in handling a tooth with a wide open apex requiring endodontic treatment is by means of a procedure called apexification. The objective of treatment is to introduce calcium hydroxide mixed with sterile water or local anaesthetic into the root canal to create a hard-tissue-like formation or an apical plug to prevent extrusion of filling materials during obturation of teeth with wide open apices. This procedure may take anything from 6 months to 2 years. In 1999 a new material called mineral trioxide aggregate (MTA) was introduced to the dental profession for clinical use which has the ability to create an apical plug within a few weeks.

  11. Frecuencia de periodontitis apical en tratamientos endodónticos de pregrado Frequency of apical periodontitis in endodontic treatment in undergraduate

    OpenAIRE

    León, P; MJ Ilabaca; M Alcota; FE González

    2011-01-01

    La periodontitis apical es una enfermedad de los tejidos periapicales de etiología bacteriana. Su tratamiento requiere erradicar los microorganismos del conducto radicular y obturarlo para lograr la reparación posterior. El objetivo de éste trabajo fue determinar la frecuencia de periodontitis apical en la población que asiste a la clínica de Endodoncia de la Facultad de Odontología de la Universidad de Chile y su relación con diferentes variables: diagnóstico específico, edad, sexo, agudas v...

  12. Fully Coupled Time-Domain Simulation of Dynamic Positioning Semi-Submersible Platform Using Dynamic Surface Control

    Institute of Scientific and Technical Information of China (English)

    LIANG Haizhi; LI Luyu; OU Jinping

    2014-01-01

    A fully coupled 6-degree-of-freedom nonlinear dynamic model is presented to analyze the dynamic response of a semi-submersible platform which is equipped with the dynamic positioning (DP) system. In the control force design, a dynamic model of reference linear drift frequency in the horizontal plane is introduced. The dynamic surface control (DSC) is used to design a control strategy for the DP. Compared with the traditional back-stepping methods, the dynamic surface control combined with radial basis function (RBF) neural networks (NNs) can avoid differentiating intermediate variables repeatedly in every design step due to the introduction of a first order filter. Low frequency motions obtained from total motions by a low pass filter are chosen to be the inputs for the RBF NNs which are used to approximate the low frequency wave force. Considering the propellers’ wear and tear, the effect of filtering frequencies for the control force is discussed. Based on power consumptions and positioning requirements, the NN cen-ters are determined. Moreover, the RBF NNs used to approximate the total wave force are built to monitor the disturbances. With the DP assistance, the results of fully coupled dynamic response simulations are given to illustrate the effectiveness of the proposed con-trol strategy.

  13. Writing magnetic phase and domain structure in FeRh by controlling lattice symmetry with strain doping

    Science.gov (United States)

    Ward, T. Zac; Herklotz, Andreas; Wong, Anthony; Bennett, Steven; Lauter, Valeria

    Low energy helium ion implantation is an effective approach to strain doping materials which allows one to expand the out-of-plane lattice parameter in epitaxial films without vacancy generation or electron/hole doping the system. The ability to control crystal anisotropy and overcome Poisson's drive to conserve volume can thus offer huge dividends in controlling magnetic properties due to magnetostrictive phenomena. We present recent studies on epitaxial FeRh films which demonstrate how controlling crystal symmetry in this important intermetallic material can be used to finely control magnetic properties. We find that the first order magneto-structural phase transition from antiferromagnetic to ferromagnetic can be directly controlled through single axis lattice expansion; this effectively allows us to dictate the transition temperature anywhere between 400K and 150K. Polarized Neutron Reflectometry (PNR) data and scanning Magneto-optic Kerr effect (MOKE) measurements will be presented which demonstrate that this phase control can be confined to a specific region of the film both in depth and/or lateral position. While this holds great promise for magnetocaloric applications, many possibilities remain for devising new functionalities and gaining a deeper understanding of material properties using this technique.

  14. Pulp microbiology of complete teeth with idiopathic apical lesions.

    Directory of Open Access Journals (Sweden)

    Patricia Rodríguez

    2009-11-01

    Full Text Available Introduction: Periapical changes named as lesions, in teeth with full crown integrity and without history of trauma, do not show a clear aetiology. Objective: To determine the presence of microorganisms in pulp dental tissue will clarify the cause of its death and therefore the damage to periodontal tissues. Materials and methods: From people between 10 and 39 years old, 23 teeth were selected. The samples were taken with paper points and 0.8 sterile files, and were transported in VMGA III medium, to be processed in the following 24 hours after they were taken and sowed in Brucella-agar. Results: The most affected teeth were upper central incisors, 43.8%. From the 23 studied teeth, microbiological grow was seen on 20 teeth. The following microorganisms species were identified: Fusobacterium spp., 25%, Eubacterium spp., 15%; Peptostreptococcus spp., 10%; Campylobacter spp., 10%; gram negative enteric bacteria, 10%; Porphyromonas gingivalis, 10%; Prevotella intermedia, 5%; Eikenellia corrodens, 5%; Dialister pneumosintes, 5%; and yeasts, 5%. There was no growing evidence of Actinomyces actinomycetemcomitans, Tanerella forsythensis and Streptococcus β  hemolytic. Discussion and conclusions: Sound pulp dental tissue is sterile; an injury over it will cause its inflammation, degeneration, death and bacterial contamination. Results in the present study clearly show the presence of microorganisms in closed apical dental lesions of endodontic origin. In same manner, it was seen that a great part of microorganisms species found can be regarded as periodontal pathogens. This could suggest a management with an endodontic, a periodontic and a pharmacological combined treatment.

  15. Brachial Plexopathy in Apical Non-Small Cell Lung Cancer Treated With Definitive Radiation: Dosimetric Analysis and Clinical Implications

    Energy Technology Data Exchange (ETDEWEB)

    Eblan, Michael J.; Corradetti, Michael N.; Lukens, J. Nicholas; Xanthopoulos, Eric [Department of Radiation Oncology, Abramson Cancer Center, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania (United States); Mitra, Nandita [Department of Biostatistics and Epidemiology, Abramson Cancer Center, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania (United States); Christodouleas, John P.; Grover, Surbhi; Fernandes, Annemarie T. [Department of Radiation Oncology, Abramson Cancer Center, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania (United States); Langer, Corey J.; Evans, Tracey L.; Stevenson, James [Department of Medical Oncology, Abramson Cancer Center, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania (United States); Rengan, Ramesh [Department of Radiation Oncology, Abramson Cancer Center, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania (United States); Apisarnthanarax, Smith, E-mail: apisarns@uphs.upenn.edu [Department of Radiation Oncology, Abramson Cancer Center, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania (United States)

    2013-01-01

    Purpose: Data are limited on the clinical significance of brachial plexopathy in patients with apical non-small cell lung cancers (NSCLC) treated with definitive radiation therapy. We report the rates of radiation-induced brachial plexopathy (RIBP) and tumor-related brachial plexopathy (TRBP) and associated dosimetric parameters in apical NSCLC patients. Methods and Materials: Charts of NSCLC patients with primary upper lobe or superiorly located nodal disease who received {>=}50 Gy of definitive conventionally fractionated radiation or chemoradiation were retrospectively reviewed for evidence of brachial plexopathy and categorized as RIBP, TRBP, or trauma-related. Dosimetric data were gathered on ipsilateral brachial plexuses (IBP) contoured according to Radiation Therapy Oncology Group atlas guidelines. Results: Eighty patients were identified with a median follow-up and survival time of 17.2 and 17.7 months, respectively. The median prescribed dose was 66.6 Gy (range, 50.4-84.0), and 71% of patients received concurrent chemotherapy. RIBP occurred in 5 patients with an estimated 3-year rate of 12% when accounting for competing risk of death. Seven patients developed TRBP (estimated 3-year rate of 13%), comprising 24% of patients who developed locoregional failures. Grade 3 brachial plexopathy was more common in patients who experienced TRBP than RIBP (57% vs 20%). No patient who received {<=}78 Gy to the IBP developed RIBP. On multivariable competing risk analysis, IBP V76 receiving {>=}1 cc, and primary tumor failure had the highest hazard ratios for developing RIBP and TRBP, respectively. Conclusions: RIBP is a relatively uncommon complication in patients with apical NSCLC tumors receiving definitive doses of radiation, while patients who develop primary tumor failures are at high risk for developing morbid TRBP. These findings suggest that the importance of primary tumor control with adequate doses of radiation outweigh the risk of RIBP in this population of

  16. Chimaerin suppresses Rac1 activation at the apical membrane to maintain the cyst structure.

    Directory of Open Access Journals (Sweden)

    Shunsuke Yagi

    Full Text Available Epithelial organs are made of a well-polarized monolayer of epithelial cells, and their morphology is maintained strictly for their proper functions. Previously, we showed that Rac1 activation is suppressed at the apical membrane in the mature organoid, and that such spatially biased Rac1 activity is required for the polarity maintenance. Here we identify Chimaerin, a GTPase activating protein for Rac1, as a suppressor of Rac1 activity at the apical membrane. Depletion of Chimaerin causes over-activation of Rac1 at the apical membrane in the presence of hepatocyte growth factor (HGF, followed by luminal cell accumulation. Importantly, Chimaerin depletion did not inhibit extension formation at the basal membrane. These observations suggest that Chimaerin functions as the apical-specific Rac1 GAP to maintain epithelial morphology.

  17. Magnetic Resonance Imaging of Transient Left Ventricular Apical Ballooning Related to Emotional Stress: a Case Report

    International Nuclear Information System (INIS)

    Transient left ventricular apical ballooning is characterized by transient wall motion abnormalities involving the left ventricular apex and mid-ventricle in the absence of coronary arterial occlusion. A 66-year-old woman presented to the emergency department with chest pain that mimicked acute myocardial infarction. An aortogram showed akinesis from the mid to apical left ventricle with sparing of the basal segments. Four days later, she underwent MRI, which demonstrated characteristic apical contractile dysfunction, the same as the aortogram, without evidence of myocardial infarction on the MRI. Two weeks later, her symptoms were resolved and follow-up echocardiography showed normal ventricular function. We suggest that MRI might be an integrated imaging diagnostic tool for the diagnosis of this syndrome, which demonstrated characteristic apical contractile dysfunction with performing cine MRI, the absence of significant coronary artery stenosis with performing coronary MR angiography and the absence of myocardial infarction with performing contrast enhanced delayed MRI

  18. Effect of the gamma radiation in the metabolic activity of the apical meristem of asparagus (Asparagus officinalis); Efecto de la radiacion gamma en la actividad metabolica del meristemo apical de esparrago (Asparagus officinalis)

    Energy Technology Data Exchange (ETDEWEB)

    Sanchez E, A.; Orozco A, J.A.; Troncoso R, R.; Ojeda C, A.J.; Mercado R, J.N.; Gardea B, A.; Tiznado H, M.E. [Centro de Investigacion en Alimentacion y Desarrollo, A.C. Carretera a la Victoria km. 0.6, A.P. 1735, Hermosillo, Sonora (Mexico); Melendrez A, R. [Universidad de Sonora, A.P. 5-088, Hermosillo, Sonora (Mexico)]. e-mail: aestrada@cascabel.ciad.mx

    2007-07-01

    The asparagus (Asparagus officinalis) is an agricultural product whose production generates a great quantity of wages as well as foreign currencies for the country because a great part of its production is exported to international markets. In direct reason to the high metabolic activity of the apical meristem, this product it possesses a short shelf life under good conditions of commercialization. Due to the above mentioned, the present work had as objective to evaluate the effect of the gamma radiation in the metabolic activity of the apical meristem of turions of asparagus during the postharvest. Turions of asparagus variety Brock of standard quality was treated with gamma radiation to absorbed dose of 1.0, 1.5, 2.0, 2.5 and 3.0 kGy using an irradiator of {sup 60}Co and stored in one controlled temperature camera maintained at 2 C during 8 days. During the experiment, the camera stayed in darkness and under conditions of high relative humidity by means of the water aspersion. Immediately before the one treatment and after 1, 2, 4 and 8 days of storage, the asparagus were sampled to evaluate the breathing speed (VRCG) by means of gas chromatography and scanning differential calorimetry (VRCDB), ethylene production (PE) by means of gas chromatography and production of metabolic heat of the apical meristem of the asparagus by means of scanning differential calorimetry (Q). Its were not found effects due to the gamma radiation in the variables of VRCG, VRCDB and Q. However, for the PE case, it was found that the doses of 1.5 and 2.5 reduced the PE from the first day of storage, while the 3 kGy dose achievement to eliminate completely the ethylene production from the first day of storage. It was concluded that the gamma radiation at the used levels in the present experiment doesn't reduce the metabolic activity of the apical meristem of the turion of asparagus although it can to improve the postharvest quality from the asparagus when reducing the ethylene

  19. A membrane fusion protein αSNAP is a novel regulator of epithelial apical junctions.

    Directory of Open Access Journals (Sweden)

    Nayden G Naydenov

    Full Text Available Tight junctions (TJs and adherens junctions (AJs are key determinants of the structure and permeability of epithelial barriers. Although exocytic delivery to the cell surface is crucial for junctional assembly, little is known about the mechanisms controlling TJ and AJ exocytosis. This study was aimed at investigating whether a key mediator of exocytosis, soluble N-ethylmaleimide sensitive factor (NSF attachment protein alpha (αSNAP, regulates epithelial junctions. αSNAP was enriched at apical junctions in SK-CO15 and T84 colonic epithelial cells and in normal human intestinal mucosa. siRNA-mediated knockdown of αSNAP inhibited AJ/TJ assembly and establishment of the paracellular barrier in SK-CO15 cells, which was accompanied by a significant down-regulation of p120-catenin and E-cadherin expression. A selective depletion of p120 catenin effectively disrupted AJ and TJ structure and compromised the epithelial barrier. However, overexpression of p120 catenin did not rescue the defects of junctional structure and permeability caused by αSNAP knockdown thereby suggesting the involvement of additional mechanisms. Such mechanisms did not depend on NSF functions or induction of cell death, but were associated with disruption of the Golgi complex and down-regulation of a Golgi-associated guanidine nucleotide exchange factor, GBF1. These findings suggest novel roles for αSNAP in promoting the formation of epithelial AJs and TJs by controlling Golgi-dependent expression and trafficking of junctional proteins.

  20. Analysis of apical deviation by type of system used to drive NRT® MANI rotary instruments

    Directory of Open Access Journals (Sweden)

    Elise Sasso Faccin

    2014-01-01

    Full Text Available Purpose: One of the major challenges encountered in treatment of curved canals is maintaining their original features. This study aimed to examine whether the type of system used with NRT® rotary instruments might in fl uence the occurrence of deviation in the apical region. Methods: Twenty simulated curved canals were divided into two experimental groups. In Group 1, canal preparation was performed with the pneumatic hand piece, using constant speed, but without torque control. In Group 2, an electric motor with constant speed and torque control was used. The simulated blocks were photographed before and after preparation using a platform to maintain the same position in both photographs. Images were manipulated in Adobe Photoshop® to evaluate deviation at 1 mm and 3 mm from the working length (WL. The t test was used for statistical analysis of data. The signi fi cance level was set at 1%. Results and Conclusion: Group 2 (electric motor had lower values for deviation at both locations analyzed (1 mm and 3 mm from the WL. In both groups, sites 3 mm from the WL had lower mean deviation than sites 1 mm from WL.

  1. Comparison of Apical Microleakage of Lateral Compaction Technique and Vertical Compaction Technique

    Institute of Scientific and Technical Information of China (English)

    Sahibzada Mohammad Noor; Xie Xiao Li

    2007-01-01

    Objective: The aim of this study was to assess the sealing ability of lateral compaction technique and vertical compaction technique using glucose penetration model. Glucose penetration model (GPM) has only twice been used earlier, hence the second aim of the study was to correlate the results of this study to other results and to validate the efficacy of GPM. Materals and Methods: Fifty three straight anterior human maxillary teeth were randomly divided into five groups.Root canals were prepared using crown down technique. Group A had fourteen teeth. They were compacted using vertical compaction technique. AH plus was used as root canal sealer. Group B had eight teeth. These were also compacted with vertical compaction but without AH plus. Group C had thirteen teeth. All the teeth in group C were compacted using lateral compaction using AH Plus. Group D had eight teeth. The teeth in this group were compacted using lateral compaction technique without AH plus. Group E had ten teeth. This group was assigned as negative control group. The specimen of the negative control group were completely coated with aryldite. The roots of the experimental groups were covered with aryldite, except for the root canal orifices, and apical apices. The coronal end of the decoronated tooth was connected to a plastic tube that contained 18% glucose solution. Leakage along the root filling was measured by the concentration of glucose in apical reservoir at 7, 14, 21 and 28 days intervals respectively after treatment. Results: Using repeated measure ANOVA, the leakage was significantly different among test groups A and C at 7, 14, 21 and 28 days interval respectively(P < 0.001). Data from Groups C and D also varied significantly. No statistical difference was found between groups A, B and D. Glucose concentrations at 21,28 days were higher than that at 7, 14 days in all of the four groups. Conclusion:The sealing ability of lateral compaction technique was found to be better than

  2. Effect of needle insertion depth and apical diameter on irrigant extrusion in simulated immature permanent teeth

    Directory of Open Access Journals (Sweden)

    AKSEL Hacer

    2014-09-01

    Full Text Available The aim of this study was to compare the amount of irrigant extrusion in simulated immature permanent teeth when the apical diameter and needle insertion depth were varied. Thirty single-rooted maxillary incisors with straight root canals were selected. The root length was standardized to a length of 9 mm. The teeth were divided into two experimental groups according to the degree of apical enlargement (n = 15. The apices were enlarged to a diameter of 1.10 mm or 1.70 mm by using a #3 or #6 peeso reamer, respectively, to simulate immature teeth. The irrigation solution was applied 2 or 4 mm short of the working length (WL in each experimental group. The glass vial model was used for the collection of extruded irrigant beyond the root apex. A two-way repeated measures analysis of variance test showed that there was no significant difference between different needle insertion depths (2 and 4 mm short of the WL in the group with an apical diameter of 1.70 mm (p > 0.05. In the group with an apical diameter of 1.10 mm, a 32% increase in irrigant extrusion was observed when the needle was positioned at 2 mm (p < 0.05. Regarding the effect of apical diameter, the group with a diameter of 1.70 mm showed more apical extrusion of the irrigant (34% increase for the needle positioned at 2 mm and 68% increase for the needle positioned at 4 mm. It was observed that the needle insertion depth and apical diameter have a significant effect on irrigant extrusion in immature permanent teeth.

  3. Comparison of Apical Axial Derotation between Adolescent Idiopathic and Neuromuscular Scoliosis with Pedicle Screw Instrumentation

    OpenAIRE

    Modi, Hitesh N.; Suh, Seung-Woo; Srinivasalu, S.; Mehta, Satyen; Yang, Jae-Hyuk

    2008-01-01

    Study Design A retrospective study. Purpose To compare outcomes of apical derotation with pedicle screws in idiopathic and neuromuscular scoliosis (NMS). Overview of Literature No information about apical derotation in NMS with pedicle screws is available. Methods We performed deformity correcting surgery using pedicle screw constructs on 12 adolescent idiopathic scoliosis (AIS) patients (mean age 14.1 years) and 16 NMS patients (mean age 16.5 years). Preoperative, postoperative, and final fo...

  4. Cholesterol depletion of enterocytes. Effect on the Golgi complex and apical membrane trafficking

    DEFF Research Database (Denmark)

    Hansen, Gert Helge; Niels-Christiansen, L L; Thorsen, Evy;

    2000-01-01

    Intestinal brush border enzymes, including aminopeptidase N and sucrase-isomaltase, are associated with "rafts" (membrane microdomains rich in cholesterol and sphingoglycolipids). To assess the functional role of rafts in the present work, we studied the effect of cholesterol depletion on apical......-associated. Our results implicate the Golgi complex/trans-Golgi network in raft formation and suggest a close relationship between this event and apical membrane trafficking....

  5. Apical ballooning with mid-ventricular obstruction: the many faces of Takotsubo cardiomyopathy

    OpenAIRE

    Spadotto, Veronica; ElMaghawry, Mohamed; Zorzi, Alessandro; Migliore, Federico; Marra, Martina Perazzolo

    2013-01-01

    Takotsubo cardiomyopathy (TTC) is a transient left ventricular dysfunction due to akinesia of the left-ventricular (LV) mid-apical segments (apical ballooning), which can cause severe reduction in LV systolic function. The typical clinical picture of TTC include chest pain, electrocardiographic changes consisting of mild ST-segment elevation followed by diffuse deep T-wave inversion, QTc interval prolongation and mild troponin release in the absence of significant coronary stenoses. The syndr...

  6. Cochlear outer hair cells undergo an apical circumference remodeling constrained by the hair bundle shape.

    Science.gov (United States)

    Etournay, Raphaël; Lepelletier, Léa; Boutet de Monvel, Jacques; Michel, Vincent; Cayet, Nadège; Leibovici, Michel; Weil, Dominique; Foucher, Isabelle; Hardelin, Jean-Pierre; Petit, Christine

    2010-04-01

    Epithelial cells acquire diverse shapes relating to their different functions. This is particularly relevant for the cochlear outer hair cells (OHCs), whose apical and basolateral shapes accommodate the functioning of these cells as mechano-electrical and electromechanical transducers, respectively. We uncovered a circumferential shape transition of the apical junctional complex (AJC) of OHCs, which occurs during the early postnatal period in the mouse, prior to hearing onset. Geometric analysis of the OHC apical circumference using immunostaining of the AJC protein ZO1 and Fourier-interpolated contour detection characterizes this transition as a switch from a rounded-hexagon to a non-convex circumference delineating two lateral lobes at the neural side of the cell, with a negative curvature in between. This shape tightly correlates with the 'V'-configuration of the OHC hair bundle, the apical mechanosensitive organelle that converts sound-evoked vibrations into variations in cell membrane potential. The OHC apical circumference remodeling failed or was incomplete in all the mouse mutants affected in hair bundle morphogenesis that we tested. During the normal shape transition, myosin VIIa and myosin II (A and B isoforms) displayed polarized redistributions into and out of the developing lobes, respectively, while Shroom2 and F-actin transiently accumulated in the lobes. Defects in these redistributions were observed in the mutants, paralleling their apical circumference abnormalities. Our results point to a pivotal role for actomyosin cytoskeleton tensions in the reshaping of the OHC apical circumference. We propose that this remodeling contributes to optimize the mechanical coupling between the basal and apical poles of mature OHCs.

  7. 24 Hour ST Segment Analysis in Transient Left Ventricular Apical Ballooning

    OpenAIRE

    Frank Bode; Christof Burgdorf; Heribert Schunkert; Volkhard Kurowski

    2013-01-01

    OBJECTIVE: The etiologic basis of transient left ventricular apical ballooning, a novel cardiac syndrome, is not clear. Among the proposed pathomechanisms is coronary vasospasm. Long-term ST segment analysis may detect vasospastic episodes but has not been reported. METHODS: 30 consecutive patients with transient left ventricular apical ballooning, left ventricular dysfunction and normal or near-normal coronary arteries were investigated. A 24-hour Holter ECG was obtained after emergency admi...

  8. RNG1 is a Late Marker of the Apical Polar Ring in Toxoplasma gondii

    OpenAIRE

    Tran, Johnson Q.; de Leon, Jessica C.; Li, Catherine; Huynh, My-Hang; Beatty, Wandy; Morrissette, Naomi S.

    2010-01-01

    The asexually proliferating stages of apicomplexan parasites cause acute symptoms of diseases such as malaria, cryptosporidiosis and toxoplasmosis. These stages are characterized by the presence of two independent microtubule organizing centers (MTOCs). Centrioles are found at the poles of the intranuclear spindle. The apical polar ring (APR), a MTOC unique to apicomplexans, organizes subpellicular microtubules which impose cell shape and apical polarity on these protozoa. Here we describe th...

  9. Kinase domain insert containing receptor promoter controlled suicide gene system selectively kills human umbilical vein endothelial cells

    Institute of Scientific and Technical Information of China (English)

    Wen-Yu Yang; Zong-Hai Huang; Li-Jun Lin; Zhou Li; Jing-Long Yu; Hui-Juan Song; Yong Qian; Xiao-Yan Che

    2006-01-01

    AIM: To study the selective killing of human umbilical vein endothelial cells (HUVECs) by a double suicide gene under the regulation of a kinase domain insert containing receptor (KDR) promoter and mediated by an adenoviral gene vector.METHODS: Human KDR promoter was cloned by polymerase chain reaction (PCR), and two recombinant adenoviral plasmids pAdKDR-CdglyTK, pAdCMV-CDglyTK were constructed according to a two-step transformation protocol. These two newly constructed plasmids were then transfected into 293 packaging cells to grow adenovirus, which were further multiplied and purified.HUVECs and LoVo cells were infected with either of the two resultant recombinant adenoviruses (AdKDR-CDglyTK and AdCMV-CDglyTK) respectively, and the infection rates were estimated by detection of green fluorescent protein (GFP) expression. Infected cells were cultured in culture media containing different concentrations of 5-fluorocytosine (5-FC) and ganciclovir (GCV), and the killing effects were measured.RESULTS: The two recombinant adenoviral plasmids pAdKDR-CdglyTK, pAdCMV-CDglyTK were successfully constructed and transfected into 293 cells. The resultant recombinant adenoviruses infected cells caused similar infection rates; and the infected cells exhibited different sensitivity to the prodrugs: HUVECs infected with AdCMV-CDglyTK and LoVo cells infected with AdCMVCDglyTK were highly sensitive to the prodrugs, and HUVECs infected with AdKDR-CDglyTK were similarly sensitive but significantly more sensitive than the LoVo cells infected with AdKDR-CdglyTK (P<0.001).CONCLJSION: Selective killing of HUVECs may be achieved by gene transfer of double suicide gene under the regulation of the KDR promoter. This finding may provide an optional way to target gene therapy of malignant tumors by abrogation of tumor blood vessels.

  10. SET DOMAIN GROUP 708, a histone H3 lysine 36-specific methyltransferase, controls flowering time in rice (Oryza sativa).

    Science.gov (United States)

    Liu, Bing; Wei, Gang; Shi, Jinlei; Jin, Jing; Shen, Ting; Ni, Ting; Shen, Wen-Hui; Yu, Yu; Dong, Aiwu

    2016-04-01

    As a key epigenetic modification, the methylation of histone H3 lysine 36 (H3K36) modulates chromatin structure and is involved in diverse biological processes. To better understand the language of H3K36 methylation in rice (Oryza sativa), we chose potential histone methylation enzymes for functional exploration. In particular, we characterized rice SET DOMAIN GROUP 708 (SDG708) as an H3K36-specific methyltransferase possessing the ability to deposit up to three methyl groups on H3K36. Compared with the wild-type, SDG708-knockdown rice mutants displayed a late-flowering phenotype under both long-day and short-day conditions because of the down-regulation of the key flowering regulatory genes Heading date 3a (Hd3a), RICE FLOWERING LOCUS T1 (RFT1), and Early heading date 1 (Ehd1). Chromatin immunoprecipitation experiments indicated that H3K36me1, H3K36me2, and H3K36me3 levels were reduced at these loci in SDG708-deficient plants. More importantly, SDG708 was able to directly target and effect H3K36 methylation on specific flowering genes. In fact, knockdown of SDG708 led to misexpression of a set of functional genes and a genome-wide decrease in H3K36me1/2/3 levels during the early growth stages of rice. SDG708 is a methyltransferase that catalyses genome-wide deposition of all three methyl groups on H3K36 and is involved in many biological processes in addition to flowering promotion. PMID:26639303

  11. The PDZ domain of the guanine nucleotide exchange factor PDZGEF directs binding to phosphatidic acid during brush border formation.

    Directory of Open Access Journals (Sweden)

    Sarah V Consonni

    Full Text Available PDZGEF is a guanine nucleotide exchange factor for the small G protein Rap. It was recently found that PDZGEF contributes to establishment of intestinal epithelial polarity downstream of the kinase Lkb1. By binding to phosphatidic acid enriched at the apical membrane, PDZGEF locally activates Rap2a resulting in induction of brush border formation via a pathway that includes the polarity players TNIK, Mst4 and Ezrin. Here we show that the PDZ domain of PDZGEF is essential and sufficient for targeting PDZGEF to the apical membrane of polarized intestinal epithelial cells. Inhibition of PLD and consequently production of phosphatidic acid inhibitis targeting of PDZGEF to the plasma membrane. Furthermore, localization requires specific positively charged residues within the PDZ domain. We conclude that local accumulation of PDZGEF at the apical membrane during establishment of epithelial polarity is mediated by electrostatic interactions between positively charged side chains in the PDZ domain and negatively charged phosphatidic acid.

  12. Comparison of Irrigation Penetration into the Apical Part of Canals in Hand and Rotary Instrumentations

    Directory of Open Access Journals (Sweden)

    M. Khabiri

    2007-01-01

    Full Text Available Introduction: The penetration of irrigating solution to the apical one third of canals and removal of debris are dependent on the final size of the instruments and instrumentation techniques used in the canals. The purpose of this study was to evaluate the effect of final instrument size, on irrigation penetration into the apical part of canals in hand K-file instrumentation versus rotary system of Hero 642.Methods and Materials: The mesiobuccal canals of 48 first mandibular molar teeth were selected for this study. The teeth were divided into 2 groups of 24 in each and the mesiobuccal canals were instrumented by hand K-file or rotary system of Hero 642 at 2 stages. After each stage, a contrast medium was injected into the canals and radiographs were taken by RVG system. The irrigation penetration was measured in radiographs by Diamax software. The data were analyzed using t – student test.Results: This study showed that instrumentation up to # 25 file is not enough for irrigation penetration into the apical area. Also by more flaring the canals, more irrigating solution penetrates into the apical part of canals (P 0 0.001, but the difference between hand and rotary systems was not statistically significant (P > 0.05.Discussion: According to this study, instrumentation up to # 30 file results in better irrigation penetration into the apical area. The flaring of the canals is essential for better cleaning and irrigation of apical area.

  13. Calcium-enriched mixture cement as artificial apical barrier: A case series

    Directory of Open Access Journals (Sweden)

    Ali Nosrat

    2011-01-01

    Full Text Available In comparison to the conventional apexification using calcium hydroxide, artificial apical barrier technique is more valuable and less time consuming. This article describes successful use of calcium-enriched mixture (CEM cement as an artificial apical barrier in open apices. In this study, 13 single-rooted teeth with necrotic pulps and open apices were treated non-surgically. After copious irrigation of the root canals with NaOCl 5.25% and gentle filing, based on need for interappointment dressing, treatments were followed by CEM cement (BioniqueDent, Tehran, Iran apical plug insertion in the first or second appointment. All cases were then permanently restored. All subjects were followed until radiographic evidence of periradicular healing was seen (mean 14.5 months. Clinically, all cases were functional and asymptomatic and complete osseous healing was observed in all the teeth. Considering the biological properties of CEM cement, this new endodontic biomaterial might be appropriate to be used as artificial apical barrier in the open apex teeth.

  14. Extending brain-training to the affective domain: increasing cognitive and affective executive control through emotional working memory training.

    Directory of Open Access Journals (Sweden)

    Susanne Schweizer

    Full Text Available So-called 'brain-training' programs are a huge commercial success. However, empirical evidence regarding their effectiveness and generalizability remains equivocal. This study investigated whether brain-training (working memory [WM] training improves cognitive functions beyond the training task (transfer effects, especially regarding the control of emotional material since it constitutes much of the information we process daily. Forty-five participants received WM training using either emotional or neutral material, or an undemanding control task. WM training, regardless of training material, led to transfer gains on another WM task and in fluid intelligence. However, only brain-training with emotional material yielded transferable gains to improved control over affective information on an emotional Stroop task. The data support the reality of transferable benefits of demanding WM training and suggest that transferable gains across to affective contexts require training with material congruent to those contexts. These findings constitute preliminary evidence that intensive cognitively demanding brain-training can improve not only our abstract problem-solving capacity, but also ameliorate cognitive control processes (e.g. decision-making in our daily emotive environments.

  15. Intramolecular trimerization, a novel strategy for making multispecific antibodies with controlled orientation of the antigen binding domains

    DEFF Research Database (Denmark)

    Álvarez-Cienfuegos, Ana; Alanes, Natalia Nuñez del Prado; Compte, Marta;

    2016-01-01

    three VHH-TIEXVIII modules on a single polypeptide chain, we present an approach for the rational design of multispecific tandem trimerbodies with defined stoichiometry and controlled orientation. Using this technology we report here the construction and characterization of a tandem VHH-based trimerbody...

  16. Effect of the gamma radiation in the metabolic activity of the apical meristem of asparagus (Asparagus officinalis)

    International Nuclear Information System (INIS)

    The asparagus (Asparagus officinalis) is an agricultural product whose production generates a great quantity of wages as well as foreign currencies for the country because a great part of its production is exported to international markets. In direct reason to the high metabolic activity of the apical meristem, this product it possesses a short shelf life under good conditions of commercialization. Due to the above mentioned, the present work had as objective to evaluate the effect of the gamma radiation in the metabolic activity of the apical meristem of turions of asparagus during the postharvest. Turions of asparagus variety Brock of standard quality was treated with gamma radiation to absorbed dose of 1.0, 1.5, 2.0, 2.5 and 3.0 kGy using an irradiator of 60Co and stored in one controlled temperature camera maintained at 2 C during 8 days. During the experiment, the camera stayed in darkness and under conditions of high relative humidity by means of the water aspersion. Immediately before the one treatment and after 1, 2, 4 and 8 days of storage, the asparagus were sampled to evaluate the breathing speed (VRCG) by means of gas chromatography and scanning differential calorimetry (VRCDB), ethylene production (PE) by means of gas chromatography and production of metabolic heat of the apical meristem of the asparagus by means of scanning differential calorimetry (Q). Its were not found effects due to the gamma radiation in the variables of VRCG, VRCDB and Q. However, for the PE case, it was found that the doses of 1.5 and 2.5 reduced the PE from the first day of storage, while the 3 kGy dose achievement to eliminate completely the ethylene production from the first day of storage. It was concluded that the gamma radiation at the used levels in the present experiment doesn't reduce the metabolic activity of the apical meristem of the turion of asparagus although it can to improve the postharvest quality from the asparagus when reducing the ethylene production

  17. Trusted Domain

    DEFF Research Database (Denmark)

    Hjorth, Theis Solberg; Torbensen, Rune

    2012-01-01

    In the digital age of home automation and with the proliferation of mobile Internet access, the intelligent home and its devices should be accessible at any time from anywhere. There are many challenges such as security, privacy, ease of configuration, incompatible legacy devices, a wealth...... of wireless standards, limited resources of embedded systems, etc. Taking these challenges into account, we present a Trusted Domain home automation platform, which dynamically and securely connects heterogeneous networks of Short-Range Wireless devices via simple non-expert user. interactions, and allows...... that enables secure end-to-end communication with home automation devices, and it supports device revocations as well as a structure of intersecting sets of nodes for scalability. Devices in the Trusted Domain are registered in a list that is distributed using a robust epidemic protocol optimized...

  18. Endodontic management of nonvital permanent teeth having immature roots with one step apexification, using mineral trioxide aggregate apical plug and autogenous platelet-rich fibrin membrane as an internal matrix: Case series.

    Science.gov (United States)

    Sharma, Vivek; Sharma, Sarang; Dudeja, Pooja; Grover, Shibani

    2016-01-01

    A tooth with blunderbuss canal and open apex can be an endodontic challenge because of difficulty in obtaining an apical seal, and existing thin radicular walls which are susceptible to fracture. To overcome the limitations of traditional long-term calcium hydroxide apexification procedures, nonsurgical one step apexification using an array of materials such as mineral trioxide aggregate (MTA) has been suggested. However, adequate compaction of MTA in teeth with wide open apices can be an arduous task, and an internal matrix is required for controlled placement of MTA against which obturating material can be condensed. Platelet-rich fibrin (PRF), a second generation platelet concentrate containing several growth factors that promotes hard and soft-tissue healing, has been used as an internal matrix to create an apical plug of MTA and hence prevent extrusion of filling materials. This case series presents the endodontic management of immature permanent teeth with open apices using internal matrix of autologous PRF membrane and one step apical barrier placement of MTA. PMID:27041904

  19. p600 regulates spindle orientation in apical neural progenitors and contributes to neurogenesis in the developing neocortex

    Directory of Open Access Journals (Sweden)

    Camille Belzil

    2014-05-01

    Full Text Available Apical neural progenitors (aNPs drive neurogenesis by means of a program consisting of self-proliferative and neurogenic divisions. The balance between these two manners of division sustains the pool of apical progenitors into late neurogenesis, thereby ensuring their availability to populate the brain with terminal cell types. Using knockout and in utero electroporation mouse models, we report a key role for the microtubule-associated protein 600 (p600 in the regulation of spindle orientation in aNPs, a cellular event that has been associated with cell fate and neurogenesis. We find that p600 interacts directly with the neurogenic protein Ndel1 and that aNPs knockout for p600, depleted of p600 by shRNA or expressing a Ndel1-binding p600 fragment all display randomized spindle orientation. Depletion of p600 by shRNA or expression of the Ndel1-binding p600 fragment also results in a decreased number of Pax6-positive aNPs and an increased number of Tbr2-positive basal progenitors destined to become neurons. These Pax6-positive aNPs display a tilted mitotic spindle. In mice wherein p600 is ablated in progenitors, the production of neurons is significantly impaired and this defect is associated with microcephaly. We propose a working model in which p600 controls spindle orientation in aNPs and discuss its implication for neurogenesis.

  20. Cytotoxic effect of the debris apically extruded during three different retreatment procedures.

    Science.gov (United States)

    Silva, Emmanuel J N L; Brito, Mônica E; Ferreira, Vivian D; Belladonna, Felipe G; Neves, Aline A; Senna, Plinio M; De-Deus, Gustavo

    2016-01-01

    We evaluated the cytotoxic effects of the debris apically extruded during root canal retreatment on primary human osteoblast (HOb) cells in vitro. TNF-α and IL-1β levels were also measured. We examined three different techniques: conventional hand-files, and Mtwo and Reciproc retreatments. Filled mandibular incisors were prepared for a cytotoxicity assay in an experimental root model. The material was divided into three groups according to the technique used. Ten teeth were used as control. HOb cells were exposed to the extruded content and cytotoxicity was evaluated using the MTT test (assessing cell metabolic activity). TNF-α and IL-1β production was also analyzed using enzyme-linked immunosorbent assay. Then, all the teeth were radiographed and the residual filling material was quantified. Data were subjected to analysis of variance (ANOVA) and Tukey's test (P endodontic retreatment techniques led to a significant upregulation of IL-1β levels (P 0.05). The Reciproc system required less time than the other two methods to remove the root-filling materials (P endodontic retreatment with Reciproc was the least cytotoxic and the least time-consuming method of gutta-percha and sealer removal. (J Oral Sci 58, 211-217, 2016). PMID:27349542

  1. MTA apical barrier: In vitro study of the use of ultrasonic vibration

    Science.gov (United States)

    Escribano-Escrivá, Begona; Manzano-Saiz, Alberto; Giner-Lluesma, Teresa; Collado-Castellanos, Nicolás; Muwaquet-Rodríguez, Susana

    2016-01-01

    Background The apexification is the first alternative treatment on a permanent tooth when, after a tooth trauma and in the presence of immature apex trauma, pulp necrosis occurs. Many studies have demonstrated the efficacy of mineral trioxide aggregate (MTA) as apical sealing material of choice in these cases, but has a degree of filtration as all other materials. The objective of this study was to analyze the seal ability of MTA on the duct walls in immature teeth unirradicular apexes, using indirect vibration. Material and Methods The study was conducted on 45 teeth divided into 3 groups: Group A or control group in which no vibration for placing the MTA was used, Group B and C or groups where indirect vibration analysis was used. All samples were immersed in methylene blue to assess filtration. After performing longitudinal cuts millimetric measuring were made of the degree of filtration, divided into 3 degrees (2mm each grade filtration). Results Results obtained confirm our hypothesis, obtaining lesser degree of filtration those groups in which indirect vibration (Groups B and C) was performed. It was shown that the degree of filtration is closely linked to the degree of adaptation. Conclusions MTA vibration offers better results in its adaptation to the canal walls, significantly reducing the degree of filtration. Key words:Apexification, MTA, filtration, indirect vibration. PMID:27398184

  2. Apical sealing of root canal fillings performed with five different endodontic sealers: analysis by fluid filtration

    Directory of Open Access Journals (Sweden)

    Bruno Carvalho de Vasconcelos

    2011-08-01

    Full Text Available OBJECTIVES: To evaluate the sealing ability of five root canal sealers, including two experimental cements (MBP and MTA-Obtura using the fluid filtration method. MATERIAL AND METHODS: Teeth were divided into 5 study groups: G1-AH Plus; G2-Acroseal; G3Sealapex; G4-MBP; G5-MTA-Obtura; and two controls. Chemical-mechanical preparation was performed with ProFile rotary nickel-titanium instruments 1 mm short of the apical foramen. The sealing ability was evaluated by fluid filtration at 15, 30, and 60 days. RESULTS: The statistical analysis showed significant difference between the materials at different periods (p<0.05. AH Plus and MBP had similar leakage values at 15 and 60 days, alternating with significant reduction at 30 days, while the other materials showed progressive increase in leakage values. Acroseal and Sealapex presented the best results at 15 days and the worst at 60 days. CONCLUSIONS: All sealers evaluated presented fluid leakage, with AH Plus and MBP showing the best results at the end of the experimental period. Acroseal, Sealapex, and MTA-Obtura presented increase in leakage values at longer observation periods.

  3. Do Parameters Of Irradiation Influences The Apical Sealing Of Er:YAG Laser Apicetomies?

    Science.gov (United States)

    Marques, Aparecida Maria Cordeiro; dos Santos, Jean Nunes; Pinheiro, Antonio Luiz Barbosa

    2011-08-01

    Failures on the sealing of the tooth apex are responsible for many failures of apical surgeries. The Er:YAG laser has been proposed as an alternative for the use of rotator instruments on surgical endodontics. 12 human extracted canines had root endodontic treatment being the apical limit was set at 1mm before the apical foramen and were distributed into 2 groups. On group I, apicectomy was performed with the Er:YAG laser (250 mJ/15 Hz). Apical cut was performed of perpendicular mode with 3mm from the apical foramen. On Group II, the same procedures and the same sequence as above was used, varying only the parameters of the Er:YAG laser (400 mJ/6 Hz). The specimens were divided into groups and fixed, by the cervical third, on wax. Impermeabilization of the residual root apical third was performed following the same procedures used in the cervical third but the residual apex was left free from the impermeabilization. After that, the roots were immersed in a 2% methylene blue solution and placed in a bacteriological oven for 48 h. The segments were visually observed and the one showing greatest level of dye leakage was selected and kept in individual container and coded accordingly. Apical staining was measured using a stereoscopic magnifying glass; a compass; and caliper. The results showed that Group I showed significantly different higher mean level of dye leakage (5.67±4.9, p<0.05). There was a significantly difference between the groups. It is concluded that the apicectomies carried out with 400 mJ/6 Hz showed the smallest infiltration value.

  4. Síndrome do balonamento apical secundário ao uso abusivo de descongestionante nasal Síndrome del abombamiento apical secundario al uso abusivo de descongestionante nasal Apical ballooning syndrome secondary to nasal decongestant abuse

    Directory of Open Access Journals (Sweden)

    Ricardo Wang

    2009-11-01

    Full Text Available Descrevemos um caso típico de síndrome do balonamento apical em uma paciente octogenária com alteração eletrocardiográfica, de contratilidade do ventrículo esquerdo, e que apresentou recuperação da função ventricular. A paciente é portadora de rinite alérgica e fez uso excessivo de descongestionante nasal horas antes do episódio da dor.Describimos un caso típico de síndrome de abombamiento apical en una paciente octogenaria con alteración electrocardiográfica, de contractilidad del ventrículo izquierdo, y que presentó recuperación de la función ventricular. La paciente es portadora de rinitis alérgica y hace uso excesivo de descongestionante nasal horas antes del episodio del dolor.We describe a typical case of apical ballooning syndrome in an octogenarian female patient with left ventricular wall motion abnormality on electrocardiography, whose ventricular function returned to normal. The patient has allergic rhinitis and had used nasal decongestant excessively a few hours prior to the episode of pain.

  5. Amyloid domains in the cell nucleus controlled by nucleoskeletal protein lamin B1 reveal a new pathway of mercury neurotoxicity

    Directory of Open Access Journals (Sweden)

    Florian Arnhold

    2015-02-01

    Full Text Available Mercury (Hg is a bioaccumulating trace metal that globally circulates the atmosphere and waters in its elemental, inorganic and organic chemical forms. While Hg represents a notorious neurotoxicant, the underlying cellular pathways are insufficiently understood. We identify amyloid protein aggregation in the cell nucleus as a novel pathway of Hg-bio-interactions. By mass spectrometry of purified protein aggregates, a subset of spliceosomal components and nucleoskeletal protein lamin B1 were detected as constituent parts of an Hg-induced nuclear aggregome network. The aggregome network was located by confocal imaging of amyloid-specific antibodies and dyes to amyloid cores within splicing-speckles that additionally recruit components of the ubiquitin-proteasome system. Hg significantly enhances global proteasomal activity in the nucleus, suggesting that formation of amyloid speckles plays a role in maintenance of protein homeostasis. RNAi knock down showed that lamin B1 for its part regulates amyloid speckle formation and thus likewise participates in nuclear protein homeostasis. As the Hg-induced cascade of interactions between the nucleoskeleton and protein homeostasis reduces neuronal signalling, amyloid fibrillation in the cell nucleus is introduced as a feature of Hg-neurotoxicity that opens new avenues of future research. Similar to protein aggregation events in the cytoplasm that are controlled by the cytoskeleton, amyloid fibrillation of nuclear proteins may be driven by the nucleoskeleton.

  6. Ethic Control:A New Domain of Internet Control%伦理治理:网络治理的新视域

    Institute of Scientific and Technical Information of China (English)

    许亚非

    2014-01-01

    The internet is a two-blade sword, and can be controlled from the angle of ethic control. The sound methods concerned are, firstly, to formulate internet ethic rules, and regulation; secondly, to strengthen internet ethic education and observe the ground line of internet ethic control.%网络是一柄双刃剑。对于网络问题,新形势下可从伦理治理的角度,进行网络治理。建立网络伦理原则,构建网络伦理规范,强化网络伦理教育,坚守网络伦理底线,是伦理治理的有效途径。

  7. The potassium impermeable apical membrane of insect epithelia: a target for development of safe pesticides

    Directory of Open Access Journals (Sweden)

    William R. Harvey

    1987-01-01

    Full Text Available Columnar cell apical membranes (CCAM in series with goblet cell apical membranes (GCAM form an electroosmotic barrier separating the midgut lumen from epithelial cell cytoplasm. A unique K+ ATPase in GCAM generates three gradients across this barrier. A greater than 180 mV electrical gradient (lumen positive drives amino acid uptake through voltage-dependent K+ symports. A greater than 1000-fold [H+] gradient (lumen alkaline and a greater than 10-fold [K+] gradient (lumen concentrated are adaptations to the high tannin and high K+ content, respectively, in dietary plant material. Agents which act on the apical membrane and disrupt the PD, H+, or K+ gradients are potential insecticides. Insect sensory epithelia and mammalian stria vascularis maintain similar PD and K+ gradients but would not be exposed to ingested anti-apical membrane insecticides. Following the demonstration by Sacchi et al. that Bacillus thuringiensis delta-endotoxin (Bt induces specifically a K+ conductance increase in CCAM vesicles, we find that the K+ channel blocking agent, Ba2+, completely reverses Bt inhibition of the K+-carried short circuit current in the isolated midgut of Manduca sexta. Progress in characterizing the apical membrane includes finding that fluorosulfonylbenzoyladenosine binds specifically to certain GCAM polypeptides and that CCAM vesicles can be mass produced by Ca2+ or Mg2+ precipitation from Manduca sexta midgut.

  8. In vitro study of apical leakage of root canals after different root apex resection techniques

    Directory of Open Access Journals (Sweden)

    André Augusto Franco MARQUES

    2008-12-01

    Full Text Available Objective:The aim of the present study was to evaluate in vitro apicalmarginal leakage of root canals after three root apex resectiontechniques.Material and methods: Thirty maxillary canines wereprepared chemo-mechanically to a size 40 master apical file, andenlarged by using Gates Glidden burs 2, 3 and 4. Teeth were obturatedby Tagger thermomechanical compaction technique and then dividedinto three groups (n = 10. The first group (GI was 3 mm apicalresected with Endo Z in high speed handpiece. The specimens of secondgroup (GII were 3 mm apical weared with Endo Z, and the third group(GIII had 3 mm apical resected with Er:YAG laser (500 impulse, 12pps and 300 mJ energy. After the apical sections, IRM cement wasplaced into the root-end cavity and teeth of each group were immersedin India ink for 5 days and submitted to decalcification and clarifying for marginal apical microleakage visualization with microscope.Results: The results showed statistically difference (p < 0.01 between GI and the other groups.Conclusion: The root apex cut using Endo Z promotes the lowest values of microleakage when used in apicoectomy.

  9. Midventricular Hypertrophic Cardiomyopathy with Apical Aneurysm: Potential for Underdiagnosis and Value of Multimodality Imaging

    Directory of Open Access Journals (Sweden)

    Archana Sivanandam

    2016-01-01

    Full Text Available We illustrate a case of midventricle obstructive HCM and apical aneurysm diagnosed with appropriate use of multimodality imaging. A 75-year-old African American woman presented with a 3-day history of chest pain and dyspnea with elevated troponins. Her electrocardiogram showed sinus rhythm, left atrial enlargement, left ventricular hypertrophy, prolonged QT, and occasional ectopy. After medical therapy optimization, she underwent coronary angiography for an initial diagnosis of non-ST segment elevation myocardial infarction. Her coronaries were unremarkable for significant disease but her left ventriculogram showed hyperdynamic contractility of the midportion of the ventricle along with a large dyskinetic aneurysmal apical sac. A subsequent transthoracic echocardiogram provided poor visualization of the apical region of the ventricle but contrast enhancement identified an aneurysmal pouch distal to the midventricular obstruction. To further clarify the diagnosis, cardiac magnetic resonance imaging with contrast was performed confirming the diagnosis of midventricular hypertrophic cardiomyopathy with apical aneurysm and fibrosis consistent with apical scar on delayed enhancement. The patient was medically treated and subsequently underwent elective implantable defibrillator placement in the ensuing months for recurrent nonsustained ventricular tachycardia and was initiated on prophylactic oral anticoagulation with warfarin for thromboembolic risk reduction.

  10. Dopants Control Electron-Hole Recombination at Perovskite-TiO₂ Interfaces: Ab Initio Time-Domain Study.

    Science.gov (United States)

    Long, Run; Prezhdo, Oleg V

    2015-11-24

    TiO2 sensitized with organohalide perovskites gives rise to solar-to-electricity conversion efficiencies reaching close to 20%. Nonradiative electron-hole recombination across the perovskite/TiO2 interface constitutes a major pathway of energy losses, limiting quantum yield of the photoinduced charge. In order to establish the fundamental mechanisms of the energy losses and to propose practical means for controlling the interfacial electron-hole recombination, we applied ab initio nonadiabatic (NA) molecular dynamics to pristine and doped CH3NH3PbI3(100)/TiO2 anatase(001) interfaces. We show that doping by substitution of iodide with chlorine or bromine reduces charge recombination, while replacing lead with tin enhances the recombination. Generally, lighter and faster atoms increase the NA coupling. Since the dopants are lighter than the atoms they replace, one expects a priori that all three dopants should accelerate the recombination. We rationalize the unexpected behavior of chlorine and bromine by three effects. First, the Pb-Cl and Pb-Br bonds are shorter than the Pb-I bond. As a result, Cl and Br atoms are farther away from the TiO2 surface, decreasing the donor-acceptor coupling. In contrast, some iodines form chemical bonds with Ti atoms, increasing the coupling. Second, chlorine and bromine reduce the NA electron-vibrational coupling, because they contribute little to the electron and hole wave functions. Tin increases the coupling, since it is lighter than lead and contributes to the hole wave function. Third, higher frequency modes introduced by chlorine and bromine shorten quantum coherence, thereby decreasing the transition rate. The recombination occurs due to coupling of the electronic subsystem to low-frequency perovskite and TiO2 modes. The simulation shows excellent agreement with the available experimental data and advances our understanding of electronic and vibrational dynamics in perovskite solar cells. The study provides design principles

  11. Estudio sobre la adaptación apical de conos maestros de gutapercha en conductos radiculares instrumentados con limas Lightspeed

    OpenAIRE

    Pumarola Suñé, José; García Campaña, Ana M.; Brau Aguadé, Esteban; Canalda Sahli, Carlos

    2000-01-01

    El objetivo de este trabajo fue establecer la coincidencia entre el calibre del cono maestro apical y la lima maestra apical, así como medir cualitativamente la adaptación de diferentes marcas de conos de gutapercha en el tercio apical de conductos radiculares instrumentados con limas Lightspeed. Se instrumentaron 100 conductos de molares naturales extraídos con el sistema Lightspeed. Las muestras se distribuyeron aleatoriamente en cinco grupos. Cada grupo fue obturado mediante condensación l...

  12. Tissue reaction to Endométhasone sealer in root canal fillings short of or beyond the apical foramen

    Directory of Open Access Journals (Sweden)

    Patrícia Suzuki

    2011-10-01

    Full Text Available OBJECTIVE: This study evaluated the response of periapical tissues to the endodontic sealer Endométhasone in root canal fillings short of or beyond the apical foramen. MATERIAL AND METHODS: Twenty root canals of premolars and incisors of 2 mongrel dogs were used. After coronal access and pulp extirpation, the canals were instrumented up to a size 55 K-file and the apical cemental barrier was penetrated with a size 15 K-file to obtain a main apical foramen, which was widened to a size 25 K-file. The canals were irrigated with saline at each change of file. The root canals were obturated either short of or beyond the apical foramen by the lateral condensation of gutta-percha and Endométhasone, originating 2 experimental groups: G1: Endométhasone/short of the apical foramen; G2: Endométhasone/beyond the apical foramen. The animals were killed by anesthetic overdose 90 days after endodontic treatment. The individual roots were obtained and serial histological sections were prepared for histomorphological analysis (H&E and Brown & Brenn techniques under light microscopy. The following parameters were examined: closure of the apical foramen of the main root canal and apical opening of accessory canals, apical cementum resorption, intensity of the inflammatory infiltrate, presence of giant cells and thickness and organization of the apical periodontal ligament. Each parameter was scored 1 to 4, 1 being the best result and 4 the worst. Data were analyzed statistically by the Wilcoxon nonparametric tests (p=0.05. RESULTS: Comparing the 2 groups, the best result (p<0.05 was obtained with root canal filling with Endométhasone short of the apical foramen but a chronic inflammatory infiltrate was present in all specimens. CONCLUSIONS: Limiting the filling material to the root canal space apically is important to determine the best treatment outcome when Endométhasone is used as sealer.

  13. Domains in Ferroelectric Nanostructures

    Science.gov (United States)

    Gregg, Marty

    2010-03-01

    Ferroelectric materials have great potential in influencing the future of small scale electronics. At a basic level, this is because ferroelectric surfaces are charged, and so interact strongly with charge-carrying metals and semiconductors - the building blocks for all electronic systems. Since the electrical polarity of the ferroelectric can be reversed, surfaces can both attract and repel charges in nearby materials, and can thereby exert complete control over both charge distribution and movement. It should be no surprise, therefore, that microelectronics industries have already looked very seriously at harnessing ferroelectric materials in a variety of applications, from solid state memory chips (FeRAMs) to field effect transistors (FeFETs). In all such applications, switching the direction of the polarity of the ferroelectric is a key aspect of functional behavior. The mechanism for switching involves the field-induced nucleation and growth of domains. Domain coarsening, through domain wall propagation, eventually causes the entire ferroelectric to switch its polar direction. It is thus the existence and behavior of domains that determine the switching response, and ultimately the performance of the ferroelectric device. A major issue, associated with the integration of ferroelectrics into microelectronic devices, has been that the fundamental properties associated with ferroelectrics, when in bulk form, appear to change quite dramatically and unpredictably when at the nanoscale: new modes of behaviour, and different functional characteristics from those seen in bulk appear. For domains, in particular, the proximity of surfaces and boundaries have a dramatic effect: surface tension and depolarizing fields both serve to increase the equilibrium density of domains, such that minor changes in scale or morphology can have major ramifications for domain redistribution. Given the importance of domains in dictating the overall switching characteristics of a device

  14. A Toxoplasma palmitoyl acyl transferase and the palmitoylated armadillo repeat protein TgARO govern apical rhoptry tethering and reveal a critical role for the rhoptries in host cell invasion but not egress.

    Directory of Open Access Journals (Sweden)

    Josh R Beck

    2013-02-01

    Full Text Available Apicomplexans are obligate intracellular parasites that actively penetrate their host cells to create an intracellular niche for replication. Commitment to invasion is thought to be mediated by the rhoptries, specialized apical secretory organelles that inject a protein complex into the host cell to form a tight-junction for parasite entry. Little is known about the molecular factors that govern rhoptry biogenesis, their subcellular organization at the apical end of the parasite and subsequent release of this organelle during invasion. We have identified a Toxoplasma palmitoyl acyltransferase, TgDHHC7, which localizes to the rhoptries. Strikingly, conditional knockdown of TgDHHC7 results in dispersed rhoptries that fail to organize at the apical end of the parasite and are instead scattered throughout the cell. While the morphology and content of these rhoptries appears normal, failure to tether at the apex results in a complete block in host cell invasion. In contrast, attachment and egress are unaffected in the knockdown, demonstrating that the rhoptries are not required for these processes. We show that rhoptry targeting of TgDHHC7 requires a short, highly conserved C-terminal region while a large, divergent N-terminal domain is dispensable for both targeting and function. Additionally, a point mutant lacking a key residue predicted to be critical for enzyme activity fails to rescue apical rhoptry tethering, strongly suggesting that tethering of the organelle is dependent upon TgDHHC7 palmitoylation activity. We tie the importance of this activity to the palmitoylated Armadillo Repeats-Only (TgARO rhoptry protein by showing that conditional knockdown of TgARO recapitulates the dispersed rhoptry phenotype of TgDHHC7 knockdown. The unexpected finding that apicomplexans have exploited protein palmitoylation for apical organelle tethering yields new insight into the biogenesis and function of rhoptries and may provide new avenues for therapeutic

  15. Controlling magnetic domain wall positions with an external magnetic field and a low spin-polarized current in chamfered L-shaped ferromagnetic thin ribbons

    Science.gov (United States)

    Honda, Syuta; Yamamoto, Daiki; Ohsawa, Tomokatsu; Gushi, Toshiki; Ito, Keita; Suemasu, Takashi

    2016-09-01

    Current-induced magnetic domain wall (DW) motion in ferromagnetic ribbons is utilized in spintronic devices. The direction of the motion changes in response to the sign of the spin-polarizability of the current through the ribbon. The DW motion is expected to measure the sign. In this study, we investigate the magnetic structures of chamfered L-shaped nano-ribbons using micro-magnetic simulations, and show that the position at which the DW is produced can be controlled by applying an external magnetic field with a low spin-polarized current (SPC). In particular, we use the material parameters of Fe4N and permalloy to simulate the magnetic structure of the ribbon. The DW can be produced at either of two locations in a chamfered corner of the ribbon, and disappears upon applying an external magnetic field. From this point, after the field is removed, a new DW is produced at either of two locations, and its position can be controlled by adjusting the low SPC.

  16. Investigating multiple components of attitude, subjective norm, and perceived control: an examination of the theory of planned behaviour in the exercise domain.

    Science.gov (United States)

    Rhodes, Ryan E; Courneya, Kerry S

    2003-03-01

    The presence of two subcomponents within each theory of planned behaviour (TPB) concept of attitude (affective and instrumental), subjective norm (injunctive and descriptive), and PBC (self-efficacy and controllability) has been widely supported. However, research has not examined whether the commonality of variance between these components (i.e. a general factor) or the specificity of variance within the subcomponents influences intention and behaviour. Therefore, the purpose of this study was to examine the optimal conceptualization of either two subcomponents or a general common factor for each TPB concept within an omnibus model. Further, to test whether conceptualizations may differ by population even within the same behavioural domain, we examined these research questions with 300 undergraduates (M age = 20) and 272 cancer survivors (M age = 61) for exercise behaviour. Results identified that a general subjective norm factor was an optimal predictive conceptualization over two separate injunctive and descriptive norm components. In contrast, a specific self-efficacy component, and not controllability or a general factor of PBC, predicted intention optimally for both samples. Finally, optimal models of attitude differed between the populations, with a general factor best predicting intention for undergraduates but only affective attitude influencing intention for cancer survivors. The findings of these studies underscore the possibility for optimal tailored interventions based on population and behaviour. Finally, a discussion of the theoretical ambiguity of the PBC concept led to suggestions for future research and possible re-conceptualization.

  17. Gibberellin Is Involved in the Regulation of Cell Death-mediated Apical Senescence in G2 Pea

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Senescence is the process of programmed degradation.The G2 line of pea exhibits apical senescence-delaying phenotype under short-day(SD)conditions,but the mechanism regulating the apical senescence is still largely unknown.Gibberellin (GA)was proved to be able to delay this apical senescence phenotype in G2 pea grown under long-day(LD) conditions.Here we show that the initiation of cell death signals in the tarminal floral meristem was involved in the regulation of apical senescence in pea plants.SD signals prevented the formation of the cell death region in the apical mersitem.Moreovsr.GA3 treatment could effectively inhibit the occurrence of cell death-mediated apical senescence in LD-grown apical buds.Therefore,our data suggest that the prevention of apical senescence in SD-grown G2 pea through GA3 treatment may be largely responsible for the regulation of occurrence of the DNA fragmentation in apical meristem.

  18. Cytotoxicity of Various Endodontic Materials on Stem Cells of Human Apical Papilla

    Science.gov (United States)

    Saberi, Eshagh Ali; Karkehabadi, Hamed; Mollashahi, Narges Farhad

    2016-01-01

    Introduction: This in vitro study assessed and compared the cytotoxicity of mineral trioxide aggregate (MTA), calcium-enriched mixture (CEM) cement, Biodentine (BD) and octacalcium phosphate (OCP) on stem cells of the human apical papilla (SCAP). Methods and Materials: SCAPs were isolated from two semi-impacted third molars. The cells were cultured in wells of an insert 24-well plate and were then incubated. The plates were then removed from the incubator and randomly divided into four experimental groups that were exposed to 1-mm discs of set MTA, CEM, BD or OCP, and one untreated control group. After 24, 48 and 168 h, the plates were removed from the incubator and 3-[4, 5-dimethylthiazol-2-yl]-2, 5-diphenyl tetrazolium bromide (MTT) solution was added to each well. Data were analyzed at different time points using the repeated measures ANOVA followed by Bonferroni test and the level of significance was set at 0.05. Results: Cytotoxicity of the four materials was not significantly different from that of the control group at 24, 48 and 168 h (P>0.05). Two-by-two comparison revealed that cytotoxicity of MTA and CEM cement was significantly different from each other at 168 h (P<0.05) although the cytotoxicity of CEM was less than MTA. Cytotoxicity of OCP and MTA was also significantly different from each other at 48 h and OCP had more favorable biocompatibility than MTA (P<0.05). Conclusion: CEM, OCP, BD and MTA showed acceptable biocompatibility when exposed to SCAP. Over time, CEM showed the least cytotoxicity among the materials under study. PMID:26843872

  19. Analyses of Interactions Between Heparin and the Apical Surface Proteins of Plasmodium falciparum

    Science.gov (United States)

    Kobayashi, Kyousuke; Takano, Ryo; Takemae, Hitoshi; Sugi, Tatsuki; Ishiwa, Akiko; Gong, Haiyan; Recuenco, Frances C.; Iwanaga, Tatsuya; Horimoto, Taisuke; Akashi, Hiroomi; Kato, Kentaro

    2013-11-01

    Heparin, a sulfated glycoconjugate, reportedly inhibits the blood-stage growth of the malaria parasite Plasmodium falciparum. Elucidation of the inhibitory mechanism is valuable for developing novel invasion-blocking treatments based on heparin. Merozoite surface protein 1 has been reported as a candidate target of heparin; however, to better understand the molecular mechanisms involved, we characterized the molecules that bind to heparin during merozoite invasion. Here, we show that heparin binds only at the apical tip of the merozoite surface and that multiple heparin-binding proteins localize preferentially in the apical organelles. To identify heparin-binding proteins, parasite proteins were fractionated by means of heparin affinity chromatography and subjected to immunoblot analysis with ligand-specific antibodies. All tested members of the Duffy and reticulocyte binding-like families bound to heparin with diverse affinities. These findings suggest that heparin masks the apical surface of merozoites and blocks interaction with the erythrocyte membrane after initial attachment.

  20. The apical oblique view of the clavicle: Its usefulness in neonatal and childhood trauma

    International Nuclear Information System (INIS)

    We analyzed clavicular radiographs of 26 patients with a history of trauma. The apical oblique projection of the clavicle was obtained with the injured side of the patient angled 450 towards the X-ray tube and a 200 cephalad angulation of the X-ray beam. This view proved to be more informative than the routine apical anteroposterior projection. It is especially effective in detecting nondisplaced fractures of the middle third of the clavicle in neonates and children. To verify our findings, we obtained apical anteroposterior and oblique radiographs of a specimen adult of the X-ray beam, the measurements of the projected lengths of the anatomical specimen, especially those of the middle portion of the clavicle, were very close to the corresponding anatomical lengths. (orig.)

  1. Evaluation of the reinforcement effect on teeth with different apical foramen diameters of retrograde or orthograde MTA application with internal matrix

    Directory of Open Access Journals (Sweden)

    Emre Bayram

    2016-01-01

    Full Text Available OBJECTIVE: The aim of this study was to determine the effect of the apical foramen diameter and different application methods of Mineral Trioxide Aggregate (MTA on the fracture resistance of simulated immature teeth using a Universal Testing Machine. MATERIALS AND METHOD: Ninety extracted human teeth were used for the fracture resistance test. The apical foramen was prepared to a diameter of 1.0 mm or 1.4 mm to simulate the open apex of immature teeth. MTA was mixed according to manufacturer's recommendations and placed into the root canals with different apical foramen diameter by four different root filling techniques: retrograde, two-phased orthograde, and ortograde with or without internal matrix. Prepared roots were marked 2 mm below the cemento-enamel junction and embedded in transparent acrylic resin in cylinder moulds. Vertical force was applied along the long axis of the tooth at a speed of 5 mm/min, and the maximum resistance to fracture for each tooth was determined in Newton. A software package was used for the statistical analysis. The data were analyzed by using one-way ANOVA and post-hoc Tukey tests. RESULTS: A statistically significant difference could not be observed between the groups (p>0.05 whereas statistically significant differences were found between the test groups and the control groups (p<0.05. CONCLUSION: There was no significant difference between different vertical root filling techniques in increasing the fracture strength of the teeth. The diameter of the apical foramen did not have a significant effect on the fracture resistance.

  2. Analysis of apical sealing of canals irradiated with Er: YAG and Nd: YAG lasers and filled with AH Plus®

    Directory of Open Access Journals (Sweden)

    Celso Luis Caldeira

    2013-03-01

    Full Text Available Introduction: Laser technology is gaining increasing importance in dental practice and also in the field of Endodontics with its ability to promote disinfection and experimentally in the preparation of root canal. The action of different types of lasers results in changes representing the increase in permeability of dentinal tissue (Er: YAG or sometimes by a decrease in melting and recrystallization of dentin (Nd: YAG. Objective: this study assessed through apical dye leakage, the influence of irradiation with two types of laser, regarding to the quality of apical sealing of endodontic fillings. Material and methods: Thirty-six single-rooted teeth were used after being prepared with the ProFile system up to size #40 instrument and then divided into four experimental and two control groups. The technique used previously to the filling was as follows: G1 – not irradiated; G2 – irradiated with Er: YAG; G3 – irradiated with Nd: YAG and G4 – irradiated with Er: YAG followed by Nd: YAG. After external waterproofing and dry, the specimens were filled with a cold vertical condensation technique, using AH Plus sealer, and immediately immersed into 0.5% methylene blue solution for subsequent cleavage. The linear values of apical marginal leakage were obtained with the aid of an optical microscope connected to a computer using the Image Lab® software. Results: Data analysis showed the non-existence of statistically significant (p = 0.05 differences between different groups. Conclusion: It was concluded that the laser does not have influence on the apical sealing.

  3. THE MODEL FOR AUXIN REGULATED AtPIN1 EXPRESSION IN THE ROOT APICAL MERISTEM

    Directory of Open Access Journals (Sweden)

    Ermakov A.A.

    2012-08-01

    Full Text Available Plant hormone auxin regulates many aspects of plant growth and development. PIN-FORMED (PIN gene family encodes transmembrane proteins, which mediate auxin efflux. PIN proteins are asymmetrically localized within cells, thereby forming in tissue auxin concentration gradients and maxima. Auxin has various effects on PIN1 expression in a cell providing for both positive and negative feedbacks on its own transport [1]. Earlier we proposed that this dual regulation determines stem cell niche maintenance in root apical meristem [2].Using two reporter lines of Arabidopsis thaliana we investigated dose-response auxin regulation of PIN1 expression at the levels of RNA and protein. PIN1::PIN1-GFP containing part of PIN1 coding region reveals both transcriptional and posttranscriptional regulation, whereas pPIN1::GUS displays only transcriptional regulation. The reporter line pPIN1::GUS[-1388;+82] was created by authors; PIN1::PIN1-GFP was provided by Alexis Peaucelle (INRA, France. PIN1::PIN1-GFP and pPIN1::GUS seedlings were grown in a 16 hours light/8 hours dark cycle at 25/22°C on 1/2MS with sucrose. Before microscopic analysis 3 dag seedlings were incubated for 24 h in liquid 1/2MS supplemented with different IAA concentrations. The experimental images were analyzed using ImageJ program.We found the following changes in PIN1 expression pattern in the root for both lines under low and moderate auxin treatments: (1 increased domain of PIN1 expression in the root meristem; (2 ectopic expression in epidermis and cortex, (3 increased level of PIN1 expression in provascular cells. However, we observed differences in PIN1 expression between the lines: in columella and under high auxin concentrations. The experimental data suggests posttranslational PIN1 regulation by high auxin concentrations. A mathematical model [2] was extended to describe the observed phenomena. The model simulation well agrees with the experimental data and predicts new aspects on the

  4. The dynamics of filamentous structures in the apical band, oral crescent, fission line and the postoral meridional filament in Tetrahymena thermophila revealed by monoclonal antibody 12G9.

    Science.gov (United States)

    Jerka-Dziadosz, M; Strzyewska-Jówko, I; Wojsa-Lugowska, U; Krawczyńska, W; Krzywicka, A

    2001-05-01

    The ciliate Tetrahymena thermophila possesses a multitude of cytoskeletal structures whose differentiation is related to the basal bodies - the main mediators of the cortical pattern. This investigation deals with immunolocalization using light and electron microscopy of filaments labeled by the monoclonal antibody 12G9, which in other ciliates identifies filaments involved in transmission of cellular polarities and marks cell meridians with the highest morphogenetic potential. In Tetrahymena interphase cells, mAb 12G9 localizes to the sites of basal bodies and to the striated ciliary rootlets, to the apical band of filaments and to the fine fibrillar oral crescent. We followed the sequence of development of these structures during divisional morphogenesis. The labeling of the maternal oral crescent disappears in pre-metaphase cells and reappears during anaphase, concomitantly with differentiation of the new structure in the posterior daughter cell. In the posterior daughter cell, the new apical band originates as small clusters of filaments located at the base of the anterior basal bodies of the apical basal body couplets during early anaphase. The differentiation of the band is completed in the final stages of cytokinesis and in the young post-dividing cell. The maternal band is reorganized earlier, simultaneously with the oral structure. The mAb 12G9 identifies two transient structures present only in dividing cells. One is a medial structure demarcating the two daughter cells during metaphase and anaphase, and defining the new anterior border of the posterior daughter cell. The other is a post-oral meridional filament marking the stomatogenic meridian in postmetaphase cells. Comparative analysis of immunolocalization of transient filaments labeled with mAb12G9 in Tetrahymena and other ciliates indicates that this antibody identifies a protein bound to filamentous structures, which might play a role in relying polarities of cortical domains and could be a part

  5. The dynamics of filamentous structures in the apical band, oral crescent, fission line and the postoral meridional filament in Tetrahymena thermophila revealed by monoclonal antibody 12G9.

    Science.gov (United States)

    Jerka-Dziadosz, M; Strzyewska-Jówko, I; Wojsa-Lugowska, U; Krawczyńska, W; Krzywicka, A

    2001-05-01

    The ciliate Tetrahymena thermophila possesses a multitude of cytoskeletal structures whose differentiation is related to the basal bodies - the main mediators of the cortical pattern. This investigation deals with immunolocalization using light and electron microscopy of filaments labeled by the monoclonal antibody 12G9, which in other ciliates identifies filaments involved in transmission of cellular polarities and marks cell meridians with the highest morphogenetic potential. In Tetrahymena interphase cells, mAb 12G9 localizes to the sites of basal bodies and to the striated ciliary rootlets, to the apical band of filaments and to the fine fibrillar oral crescent. We followed the sequence of development of these structures during divisional morphogenesis. The labeling of the maternal oral crescent disappears in pre-metaphase cells and reappears during anaphase, concomitantly with differentiation of the new structure in the posterior daughter cell. In the posterior daughter cell, the new apical band originates as small clusters of filaments located at the base of the anterior basal bodies of the apical basal body couplets during early anaphase. The differentiation of the band is completed in the final stages of cytokinesis and in the young post-dividing cell. The maternal band is reorganized earlier, simultaneously with the oral structure. The mAb 12G9 identifies two transient structures present only in dividing cells. One is a medial structure demarcating the two daughter cells during metaphase and anaphase, and defining the new anterior border of the posterior daughter cell. The other is a post-oral meridional filament marking the stomatogenic meridian in postmetaphase cells. Comparative analysis of immunolocalization of transient filaments labeled with mAb12G9 in Tetrahymena and other ciliates indicates that this antibody identifies a protein bound to filamentous structures, which might play a role in relying polarities of cortical domains and could be a part

  6. Estudio de la filtración apical de cuatro cementos de obturación

    OpenAIRE

    Roig Cayón, Miguel; Ribot Porta, J. de; Jané Noblom, L.; Canalda Sahli, Carlos

    1996-01-01

    Los autores estudian in vitro la microfiltración apical con cuatro cementos de obturación, mediante la utilización de un colorante y técnicas de diafanización. Analizan dos cementos a base de hidróxido de calcio, y uno de ionómero de vidrio, comparándolos con un cemento clásico a base de óxido de zinc-eugenol. La filtración apical del cemento sellador Apexit fue significativamente superior a la de los cementos Sealapex y Endomethasone. No se observaron diferencias significativas entre los dem...

  7. Apical Ballooning Syndrome (Takotsubo Cardiomyopathy after Permanent Dual-Chamber Pacemaker Implantation

    Directory of Open Access Journals (Sweden)

    Armando Gardini

    2012-01-01

    Full Text Available Apical ballooning syndrome, also called takotsubo cardiomyopathy, has been recently reported. It may mimic acute myocardial infarction and is typically observed in postmenopausal women after stressful events. A 75-year-old female after permanent dual chamber pacemaker implant complained of chest pain with repolarization alterations suggesting acute myocardial ischemia. Echocardiography showed a left ventricle with akinesia of the apical portions and reduced global systolic function. The patient was treated with antithrombotic agents and intravenous nitrates. No coronary lesions were found at angiography. At ventriculography, a typical takotsubo-like shape of the left ventricle was observed. The clinical and echocardiographic picture normalized at discharge.

  8. Reasons for Apical Surgery Treatment in an Underserved New York City Population.

    Science.gov (United States)

    Hasselgren, Gunnar; Patel, Pratik; Alhassany, Hashim; Kunzel, Carol

    2016-04-01

    Endodontic retreatment often involves remaking restorations. The total cost may steer the treatment towards surgery. The aim of this study was to retrospectively record the reasons for performing apical surgery in an economically deprived patient population. The clinical reasons (59%) for apical surgery were most common, but the nonclinical (financial) reasons (41%) emerged as a major cause. The finding that 41% of the apicoectomies were performed because of nonclinical constraints is a high figure and may not reflect the situation generally. Still, economic factors potentially play a major role in the selection of surgical versus nonsurgical endodontic retreatment. PMID:27348949

  9. Apical Localization of Sodium-Dependent Glucose Transporter SGLT1 is Maintained by Cholesterol and Microtubules

    OpenAIRE

    Suzuki, Takeshi; Matsuzaki, Toshiyuki; Hagiwara, Haruo; Aoki, Takeo; Tajika-Takahashi, Yukiko; Takata, Kuniaki

    2006-01-01

    A GFP-labeled sodium-dependent glucose transporter SGLT1 (SGLT-GFP) was transfected into MDCK cells. SGLT-GFP was localized at the apical membrane in confluent cells. When cellular cholesterol was depleted by methyl-β-cyclodextrin (MβCD) treatment, the localization of SGLT-GFP gradually switched from apical to whole plasma membrane. Time-lapse microscopy revealed that the effect of MβCD appeared within 30 min, and that the transition of SGLT-GFP to the whole plasma membrane was completed with...

  10. SEALING ABILITY OF GRAY MTA ANGELUS™, CPM™ AND MBPC USED AS APICAL PLUGS

    OpenAIRE

    Fernando Accorsi Orosco; Clovis Monteiro Bramante; Roberto Brandão Garcia; Norberti Bernadineli; Ivaldo Gomes de Moraes

    2008-01-01

    This study evaluated the sealing ability of apical plugs fabricated with gray MTA AngelusTM sealer, CPM TM sealer and MBPc sealer. The root canals of 98 extracted single-rooted human teeth were instrumented with #5 to #1 Gates Glidden drills according to the crown-down technique until the #1 drill could pass through the apical foramen. The specimens were then prepared with K-files, starting with an ISO 50 until an ISO 90 could be visualized 1 mm beyond the apex. After root canal preparation, ...

  11. Significance of mannose-binding lectin deficiency and nucleotide-binding oligomerization domain 2 polymorphisms in Staphylococcus aureus bloodstream infections: a case-control study.

    Directory of Open Access Journals (Sweden)

    Michael Osthoff

    Full Text Available BACKGROUND: Pathways coordinated by innate pattern recognition receptors like mannose-binding lectin (MBL and nucleotide-binding oligomerization domain 2 (NOD2 are among the first immune responses to Staphylococcus aureus (S. aureus bloodstream infections (BSI in animal models, but human data are limited. Here, we investigated the role of MBL deficiency and NOD2 mutations in the predisposition to and severity of S. aureus BSI. PATIENTS AND METHODS: A matched case-control study was undertaken involving 70 patients with S. aureus BSI and 70 age- and sex-matched hospitalized controls. MBL levels, MBL2 and NOD2 polymorphisms were analyzed. RESULTS: After adjusting for potential confounders, MBL deficiency (<0.5 µg/ml was found less frequently in cases than controls (26 vs. 41%, OR 0.4, 95% confidence interval (CI 0.20-0.95, p=0.04 as were low producing MBL genotypes (11 vs. 23%, OR 0.2, 95% CI 0.08-0.75, p=0.01, whereas NOD2 polymorphisms were similarly distributed. Cases with NOD2 polymorphisms had less organ dysfunction as shown by a lower SOFA score (median 2.5 vs. 4.5, p=0.02, whereas only severe MBL deficiency (<0.1 µg/ml was associated with life-threatening S. aureus BSI (OR 5.6, 95% CI 1.25-24.85, p=0.02. CONCLUSIONS: Contrary to animal model data, our study suggests MBL deficiency may confer protection against acquiring S. aureus BSI. NOD2 mutations were less frequently associated with multi-organ dysfunction. Further human studies of the innate immune response in S. aureus BSI are needed to identify suitable host targets in sepsis treatment.

  12. Protein-mediated inward translocation of phospholipids occurs in both the apical and basolateral plasma membrane domains of epithelial cells

    NARCIS (Netherlands)

    Pomorski, T.; Herrmann, A.; Müller, P.; van Meer, G.F.B.P.; Burger, K.N.J.

    1999-01-01

    The translocation of spin-labeled analogues of phosphatidylcholine (4- doxylpentanoyl-PC, SLPC), phosphatidylethanolamine (SL-PE), phosphatidylserine (SL-PS), and sphingomyelin (SL-SM) from the outer to the inner leaflet of the plasma membrane bilayer was investigated in dog kidney MDCK II and human

  13. Mint essential oil can induce or inhibit potato sprouting by differential alteration of apical meristem.

    Science.gov (United States)

    Teper-Bamnolker, Paula; Dudai, Nativ; Fischer, Ravit; Belausov, Eduard; Zemach, Hanita; Shoseyov, Oded; Eshel, Dani

    2010-06-01

    Sprouting of potatoes during storage, due to tuber dormancy release, is associated with weight loss and softening. Sprout-preventing chemicals, such as chlorpropham (CIPC), can negatively impact the environment and human health. Monthly thermal fogging with mint (Mentha spicata L.) essential oil (MEO) inhibited sprouting in eight potato cultivars during large-volume 6-month storage: the tubers remained firm with 38% lower weight loss after 140 days of storage. The sprout-inhibitory action may be nullified: treated tubers washed with water resumed sprouting within days, with reduced apical dominance. MEO application caused local necrosis of the bud meristem, and a few weeks later, axillary bud (AX) growth was induced in the same sprouting eye. MEO components analysis showed that 73% of its content is the monoterpene R-carvone. Tubers treated with synthetic R-carvone in equivalent dose, 4.5 microl l(-1), showed an inhibitory effect similar to that of MEO. Surprisingly, 0.5 microl l(-1) of MEO or synthetic R-carvone catalyzed AX sprouting in the tuber. To the best of our knowledge, this is the first report of an essential oil vapor inducing early sprouting of potato tubers. R-carvone caused visible damage to the meristem membrane at sprout-inhibiting, but not sprout-inducing doses, suggesting different underlying mechanisms. After 5 days' exposure to R-carvone, its derivatives transcarveol and neo-dihydrocarveol were found in buds of tubers treated with the inhibitory dose, suggesting biodegradation. These experiments demonstrate the potential of MEO vapor as an environmentally friendly alternative to CIPC in stored potatoes and as a research tool for the control of sprouting in plants. PMID:20390295

  14. Histone demethylase KDM2B inhibits the chondrogenic differentiation potentials of stem cells from apical papilla.

    Science.gov (United States)

    Wang, Jing-Jing; Dong, Rui; Wang, Li-Ping; Wang, Jin-Song; Du, Juan; Wang, Song-Lin; Shan, Zhao-Chen; Fan, Zhi-Peng

    2015-01-01

    Mesenchymal stem cells (MSCs) are a reliable resource for tissue regeneration, but the molecular mechanism underlying directed differentiation remains unclear; this has restricted potential MSC applications. Histone methylation, controlled by histone methyltransferases and demethylases, may play a key role in MSCs differentiation. Previous studies determined that KDM2B can regulate the cell proliferation and osteo/dentinogenic differentiation of MSCs. It is not known whether KDM2B is involved in the other cell lineages differentiation of MSCs. Here we used the stem cells from apical papilla (SCAPs) to study the role of KDM2B on the chondrogenic differentiation potentials in MSCs. In this study, Gain- and loss-of-function assays were applied to investigate the role of KDM2B on the chondrogenic differentiation. Alcian Blue Staining and Quantitative Analysis were used to investigate the synthesis of proteoglycans by chondrocytes. Real-time RT-PCR was used to detect the expressions of chondrogenesis related genes. The Alcian Blue staining and Quantitative Analysis results revealed that overexpression of KDM2B decreased the proteoglycans production, and real-time RT-PCR results showed that the expressions of the chondrogenic differentiation markers, COL1, COL2 and SOX9 were inhibited by overexpression of KDM2B in SCAPs. On the contrary, depletion of KDM2B increased the proteoglycans production, and inhibited the expressions of COL1, COL2 and SOX9. In conclusion, our results indicated that KDM2B is a negative regulator of chondrogenic differentiation in SCAPs and suggest that inhibition of KDM2B might improve MSC mediated cartilage regeneration. PMID:25932147

  15. Apical microinfiltration evaluation of radicular channels irradiated with Er:YAG laser in vitro

    International Nuclear Information System (INIS)

    It was evaluated, in vitro, the adaptation of the filling material (Sealer 2SR) to the root channels dentine walls treated using the endodontic technique and prepared with the Er:YAG laser, by the technique of infiltration of methylene blue dye. Using scanning electronic microscopy, the morphologic alteration of the root channel dentine was observed for one sample per studied group. Also, an evaluation of the temperature increase in the external surface of the root during the irradiations was performed for two samples per group. For each group of samples, with eleven roots each, two sub-groups had been considered: the dry, irradiated after completely dry with absorbent cones of paper, and the humid, where a cone of absorbent paper was applied for two seconds in the root canal, leaving them lightly humidified. Considering the used energies for the irradiations, the groups are: G1, control (without irradiation), G2-dry (100 mJ-10 Hz), G2-humid (100 mJ-10 Hz), G3-dry (140 mJ-6 Hz), G3-humid (140 mJ-6 Hz), G4-dry (180 mJ-6 Hz), and G4-humid (180 mJ-6 Hz). The results had shown that apical microinfiltration did not exhibit significant difference among groups. The highest increase in temperature was observed for the dry groups, with the maximum variation of temperature of 6.5 deg C. Under the scanning electronic microscopy analysis, the humid groups had presented cleaner surfaces than the dry groups. The G4-humid group presented extensive regions of fusion and resolidification of the dentine. (author)

  16. Mint essential oil can induce or inhibit potato sprouting by differential alteration of apical meristem.

    Science.gov (United States)

    Teper-Bamnolker, Paula; Dudai, Nativ; Fischer, Ravit; Belausov, Eduard; Zemach, Hanita; Shoseyov, Oded; Eshel, Dani

    2010-06-01

    Sprouting of potatoes during storage, due to tuber dormancy release, is associated with weight loss and softening. Sprout-preventing chemicals, such as chlorpropham (CIPC), can negatively impact the environment and human health. Monthly thermal fogging with mint (Mentha spicata L.) essential oil (MEO) inhibited sprouting in eight potato cultivars during large-volume 6-month storage: the tubers remained firm with 38% lower weight loss after 140 days of storage. The sprout-inhibitory action may be nullified: treated tubers washed with water resumed sprouting within days, with reduced apical dominance. MEO application caused local necrosis of the bud meristem, and a few weeks later, axillary bud (AX) growth was induced in the same sprouting eye. MEO components analysis showed that 73% of its content is the monoterpene R-carvone. Tubers treated with synthetic R-carvone in equivalent dose, 4.5 microl l(-1), showed an inhibitory effect similar to that of MEO. Surprisingly, 0.5 microl l(-1) of MEO or synthetic R-carvone catalyzed AX sprouting in the tuber. To the best of our knowledge, this is the first report of an essential oil vapor inducing early sprouting of potato tubers. R-carvone caused visible damage to the meristem membrane at sprout-inhibiting, but not sprout-inducing doses, suggesting different underlying mechanisms. After 5 days' exposure to R-carvone, its derivatives transcarveol and neo-dihydrocarveol were found in buds of tubers treated with the inhibitory dose, suggesting biodegradation. These experiments demonstrate the potential of MEO vapor as an environmentally friendly alternative to CIPC in stored potatoes and as a research tool for the control of sprouting in plants.

  17. Enigma interacts with adaptor protein with PH and SH2 domains to control insulin-induced actin cytoskeleton remodeling and glucose transporter 4 translocation

    DEFF Research Database (Denmark)

    Barres, Romain; Grémeaux, Thierry; Gual, Philippe;

    2006-01-01

    APS (adaptor protein with PH and SH2 domains) initiates a phosphatidylinositol 3-kinase-independent pathway involved in insulin-stimulated glucose transport. We recently identified Enigma, a PDZ and LIM domain-containing protein, as a partner of APS and showed that APS-Enigma complex plays...

  18. Reversible and Nonvolatile Modulations of Magnetization Switching Characteristic and Domain Configuration in L10-FePt Films via Nonelectrically Controlled Strain Engineering.

    Science.gov (United States)

    Feng, Chun; Zhao, Jiancheng; Yang, Feng; Hao, Shijie; Gong, Kui; Hu, Di; Cao, Yi; Jiang, Xumin; Wang, Zhongqiang; Chen, Lei; Li, Sirui; Sun, Li; Cui, Lishan; Yu, Guanghua

    2016-03-23

    Reversible and nonvolatile modulation of magnetization switching characteristic in ferromagnetic materials is crucial in developing spintronic devices with low power consumption. It is recently discovered that strain engineering can be an active and effective approach in tuning the magnetic/transport properties of thin films. The primary method in strain modulation is via the converse piezoelectric effect of ferroelectrics, which is usually volatile due to the reliance of the required electric field. Also the maximum amount of deformation in ferroelectrics is usually limited to be less than 1%, and the corresponding magnetoelastic strain energy introduced to ferromagnetic films is on the order of 10(4) J/m(3), not enough to overcome magnetocrystalline anisotropy energy (Ku) in many materials. Different from using conventional strain inducing substrates, this paper reports on the significantly large, reversible, and nonvolatile lattice strain in the L10-FePt films (up to 2.18%) using nonelectrically controlled shape memory alloy substrates. Introduced lattice strain can be large enough to effectively affect domain structure and magnetic reversal in FePt. A noticeable decrease of coercivity field by 80% is observed. Moreover, the coercivity field tunability using such substrates is nonvolatile at room temperature and is also reversible due to the characteristics of the shape memory effect. This finding provides an efficient avenue for developing strain assisted spintronic devices such as logic memory device, magnetoresistive random-access memory, and memristor. PMID:26939773

  19. Involvement of the Acyl-CoA binding domain containing 7 in the control of food intake and energy expenditure in mice.

    Science.gov (United States)

    Lanfray, Damien; Caron, Alexandre; Roy, Marie-Claude; Laplante, Mathieu; Morin, Fabrice; Leprince, Jérôme; Tonon, Marie-Christine; Richard, Denis

    2016-01-01

    Acyl-CoA binding domain-containing 7 (Acbd7) is a paralog gene of the diazepam-binding inhibitor/Acyl-CoA binding protein in which single nucleotide polymorphism has recently been associated with obesity in humans. In this report, we provide converging evidence indicating that a splice variant isoform of the Acbd7 mRNA is expressed and translated by some POMC and GABAergic-neurons in the hypothalamic arcuate nucleus (ARC). We have demonstrated that the ARC ACBD7 isoform was produced and processed into a bioactive peptide referred to as nonadecaneuropeptide (NDN) in response to catabolic signals. We have characterized NDN as a potent anorexigenic signal acting through an uncharacterized endozepine G protein-coupled receptor and subsequently via the melanocortin system. Our results suggest that ACBD7-producing neurons participate in the hypothalamic leptin signalling pathway. Taken together, these data suggest that ACBD7-producing neurons are involved in the hypothalamic control exerted on food intake and energy expenditure by the leptin-melanocortin pathway. PMID:26880548

  20. Involvement of auxin and CKs in boron deficiency induced changes in apical dominance of pea plants (Pisum sativum L.).

    Science.gov (United States)

    Wang, Guoying; Römheld, Volker; Li, Chunjian; Bangerth, Fritz

    2006-04-01

    It has previously been shown that boron (B) deficiency inhibits growth of the plant apex, which consequently results in a relatively weak apical dominance, and a subsequent sprouting of lateral buds. Auxin and cytokinins (CKs) are the two most important phytohormones involved in the regulation of apical dominance. In this study, the possible involvement of these two hormones in B-deficiency-induced changes in apical dominance was investigated by applying B or the synthetic CK CPPU to the shoot apex of pea plants grown in nutrient solution without B supply. Export of IAA out of the shoot apex, as well as the level of IAA, Z/ZR and isopentenyl-adenine/isopentenyl-adenosine (i-Ade/i-Ado) in the shoot apex were assayed. In addition, polar IAA transport capacity was measured in two internodes of different ages using 3H-IAA. In B-deficient plants, both the level of auxin and CKs were reduced, and the export of auxin from the shoot apex was considerably decreased relative to plants well supplied with B. Application of B to the shoot apex restored the endogenous Z/ZR and IAA level to control levels and increased the export of IAA from the shoot apex, as well as the 3H-IAA transport capacity in the newly developed internodes. Further, B application to the shoot apex inhibited lateral bud growth and stimulated lateral root formation, presumably by stimulated polar IAA transport. Applying CPPU to the shoot apex, a treatment that stimulates IAA export under adequate B supply, considerably reduced the endogenous Z/ZR concentration in the shoot apex, but had no stimulatory effect on IAA concentration and transport in B-deficient plants. A similar situation appeared to exist in lateral buds of B-deficient plants as, in contrast to plants well supplied with B, application of CKs to these plants did not stimulate lateral bud growth. In contrast to the changes of Z/ZR levels in the shoot apex, which occurred after application of B or CPPU, the levels of i-Ade/i-Ado stayed more or

  1. A correlative microscopy approach relates microtubule behaviour, local organ geometry, and cell growth at the Arabidopsis shoot apical meristem.

    Science.gov (United States)

    Burian, Agata; Ludynia, Michal; Uyttewaal, Magalie; Traas, Jan; Boudaoud, Arezki; Hamant, Olivier; Kwiatkowska, Dorota

    2013-12-01

    Cortical microtubules (CMTs) are often aligned in a particular direction in individual cells or even in groups of cells and play a central role in the definition of growth anisotropy. How the CMTs themselves are aligned is not well known, but two hypotheses have been proposed. According to the first hypothesis, CMTs align perpendicular to the maximal growth direction, and, according to the second, CMTs align parallel to the maximal stress direction. Since both hypotheses were formulated on the basis of mainly qualitative assessments, the link between CMT organization, organ geometry, and cell growth is revisited using a quantitative approach. For this purpose, CMT orientation, local curvature, and growth parameters for each cell were measured in the growing shoot apical meristem (SAM) of Arabidopsis thaliana. Using this approach, it has been shown that stable CMTs tend to be perpendicular to the direction of maximal growth in cells at the SAM periphery, but parallel in the cells at the boundary domain. When examining the local curvature of the SAM surface, no strict correlation between curvature and CMT arrangement was found, which implies that SAM geometry, and presumed geometry-derived stress distribution, is not sufficient to prescribe the CMT orientation. However, a better match between stress and CMTs was found when mechanical stress derived from differential growth was also considered.

  2. Formation and removal of apical vapor lock during syringe irrigation: a combined experimental and Computational Fluid Dynamics approach

    NARCIS (Netherlands)

    Boutsioukis, C.; Kastrinakis, E.; Lambrianidis, T.; Verhaagen, B.; Versluis, M.; Sluis, van der L.W.M.

    2014-01-01

    Aim (i) To evaluate the effect of needle type and insertion depth, root canal size and irrigant flow rate on the entrapment of air bubbles in the apical part of a root canal (apical vapor lock) during syringe irrigation using experiments and a Computational Fluid Dynamics (CFD) model, (ii) to invest

  3. Formation and removal of apical vapor lock during syringe irrigation : a combined experimental and Computational Fluid Dynamics approach

    NARCIS (Netherlands)

    Boutsioukis, C.; Kastrinakis, E.; Lambrianidis, T.; Verhaagen, B.; Versluis, M.; van der Sluis, L. W. M.

    2014-01-01

    Aim(i) To evaluate the effect of needle type and insertion depth, root canal size and irrigant flow rate on the entrapment of air bubbles in the apical part of a root canal (apical vapor lock) during syringe irrigation using experiments and a Computational Fluid Dynamics (CFD) model, (ii) to investi

  4. Apical root resorption 6 months after initiation of fixed orthodontic appliance therapy.

    NARCIS (Netherlands)

    Smale, I.M.; Artun, J.; Behbehani, F.; Doppel, D.; Hof, M.A. van 't; Kuijpers-Jagtman, A.M.

    2005-01-01

    INTRODUCTION: Individual predisposition might be a major reason for the observed variation in apical orthodontic root resorption. If so, resorption might be expressed during the initial stages of orthodontic therapy in patients at risk. METHODS: To explore this hypothesis, we evaluated standardized,

  5. The Effect of Calcium Hydroxide As an Intracanal Medication of The Apical Microleakage

    Directory of Open Access Journals (Sweden)

    Heshmat Mohajer AR

    2011-12-01

    Full Text Available Background and Aims: Nowadays, calcium hydroxide is used as a dressing for canal sterilization and repair progression of apical lesions. The aim of this study was to investigate the effect of calcium hydroxide as an intracanal medicament on the apical microleakage of root filling.Materials and Methods: In this experimental study, 46 extracted single-rooted human teeth were instrumented with step-back technique to master apical file (MAF size 35. Specimens were randomly divided into 2 groups (n = 20. In group 1, the specimens were treated with calcium hydroxide intracanal medication; and in group 2, the samples did not receive any medication. The teeth were incubated in 100% humidity at 37°C for one week. After that, calcium hydroxide was removed using irrigation with normal saline and reaming with MAF. The root canals were obturated with gutta- percha and AH26 sealer using lateral compaction technique. Specimens were incubated in 100% humility at 37°C for 72 hours and then immersed in India ink for 1 week. Finally, the teeth were cleared and the maximum linear dye penetration was measured under a stereomicroscope at 4X magnification. The data were analyzed by T-test and Chi-square.Results: There was no significant difference between the two experimental groups (P=0.068. Conclusion: The findings of this study indicated that using calcium hydroxide as an intracanal medicament did not influence the apical microleakage after final obturation of the root canal system.

  6. Cone beam computed tomography study of apical root resorption induced by Herbst appliance

    Directory of Open Access Journals (Sweden)

    João Paulo SCHWARTZ

    2015-10-01

    Full Text Available Objective This study evaluated the frequency of root resorption during the orthodontic treatment with Herbst appliance by Cone Beam Computed Tomography (CBCT.Material and Methods The sample comprised 23 patients (11 men, 12 women; mean ages 15.76±1.75 years with Class II division 1 malocclusion, treated with Herbst appliance. CBCT was obtained before treatment (T0 and after Herbst treatment (T1. All the dental roots, except third molars, were evaluated, and apical root resorption was determined using the axial guided navigation method. Paired t-tests and Wilcoxon T Test were used to compare the dependent samples in parametric and nonparametric cases, respectively. Chi-Square Test with Yates’ correction was used to evaluate the relationship between apical root resorption and gender. Results were considered at a significance level of 5%.Results Apical resorption was detected by CBCT in 57.96% of 980 roots that underwent Herbst appliance treatment. All patients had minimal resorption and there was no statistical significance between the genders.Conclusion CBCT three-dimensional evaluation showed association between Herbst appliance and minimal apical root resorption, mostly in the anchoring teeth, without clinical significance.

  7. Pulp Revascularization in Immature Permanent Tooth with Apical Periodontitis Using Mineral Trioxide Aggregate

    Directory of Open Access Journals (Sweden)

    Katsura Saeki

    2014-01-01

    Full Text Available Mineral trioxide aggregate (MTA is a material that has been used worldwide in several clinical applications, such as apical barriers in teeth with immature apices, repair of root perforations, root-end filling, pulp capping, and pulpotomy. The purpose of this case report was to describe successful revascularization treatment of an immature mandibular right second premolar with apical periodontitis in a 9-year-old female patient. After preparing an access cavity without anesthesia, the tooth was isolated using a rubber dam and accessed. The canal was gently debrided using 5% sodium hypochlorite (NaOCl and 3% hydrogen peroxide irrigant. And then MTA was packed into the canal. X-ray photographic examination showed the dentin bridge 5 months after the revascularization procedure. Thickening of the canal wall and complete apical closure were confirmed 10 months after the treatment. In this case, MTA showed clinical and radiographic success at revascularization treatment in immature permanent tooth. The successful outcome of this case suggests that MTA is reliable and effective for endodontic treatment in the pediatric dentistry.

  8. Regenerative Endodontic Treatment versus Apical Plug in Immature Teeth: Three-Year Follow-Up.

    Science.gov (United States)

    Asgary, Saeed; Fazlyab, Mahta; Nosrat, Ali

    2016-01-01

    This report compares and evaluates the treatment outcomes of regenerative endodontic treatment and apical plug as two accepted treatment protocols in a pair of necrotic immature maxillary central incisors of a 12-year old female. The patient was referred complaining of a dull pain and swelling in her upper lip area. She had a history of trauma to the anterior maxilla two years earlier. Both teeth were clinically diagnosed with pulp necrosis and periapical radiographs revealed that separate periapical radiolucent lesions surrounded the immature apices of both teeth. The left and right incisors were treated with apical plug and regenerative endodontic treatment, respectively, using calcium-enriched mixture (CEM) cement. The patient was followed-up for three years. During this period, both teeth were clinically asymptomatic and showed complete radiographic healing of the periapical lesions. The right central incisor showed root development. No tooth discoloration was evident. Apexification by apical plug placement and pulp regeneration are both reliable treatments for immature non-vital teeth. In order to choose the right treatment the advantages of either technique should be weighed against its drawbacks. CEM cement can be successfully applied for both purposes. This biomaterial causes less discoloration of the tooth. PMID:27617375

  9. Micro-CT analyses of apical enlargement and molar root canal complexity

    DEFF Research Database (Denmark)

    Markvart, Merete; Darvann, Tron Andre; Larsen, Per;

    2012-01-01

    AIM: To compare the effectiveness of two rotary hybrid instrumentation techniques with focus on apical enlargement in molar teeth and to quantify and visualize spatial details of instrumentation efficacy in root canals of different complexity. METHODOLOGY: Maxillary and mandibular molar teeth were...

  10. Right ventricular outflow and apical pacing comparably worsen the echocardioghraphic normal left ventricle

    NARCIS (Netherlands)

    T.J.F. ten Cate (Tim); M.G. Scheffer (Michael); G.R. Sutherland (George); J.F. Verzijlbergen (Fred); N.M. van Hemel (Norbert)

    2008-01-01

    textabstractAims: A depressed left ventricular function (LVF) is sometimes observed during right ventricular apical (RVA) pacing, but any prediction of this adverse effect cannot be done. Right ventricular outflow tract (RVOT) pacing is thought to deteriorate LVF less frequently because of a more no

  11. A novel mitochondrial ATP8 gene mutation in a patient with apical hypertrophic cardiomyopathy and neuropathy.

    NARCIS (Netherlands)

    Jonckheere, A.I.; Hogeveen, M.; Nijtmans, L.G.J.; Brand, M.A.M. van den; Janssen, A.J.M.; Diepstra, J.H.S.; Brandt, FC van den; Heuvel, L.P.W.J. van den; Hol, F.A.; Hofste, T.G.; Kapusta, L.; Dillmann, U.; Shamdeen, M.G.; Smeitink, J.A.M.; Rodenburg, R.J.T.

    2008-01-01

    PURPOSE: To identify the biochemical and molecular genetic defect in a 16-year-old patient presenting with apical hypertrophic cardiomyopathy and neuropathy suspected for a mitochondrial disorder. METHODS: Measurement of the mitochondrial energy-generating system (MEGS) capacity in muscle and enzyme

  12. Morphology of the Physiological Apical Foramen in Maxillary and Mandibular First Molars

    Science.gov (United States)

    Abarca, J.; Zaror, C.; Monardes, H.; Hermosilla, V.; Muñoz, C.; Cantin, M.

    2015-01-01

    SUMMARY Information regarding the anatomy of the physiological apical foramen is limited. Knowing its diameter and shapes contributes to clinical work, specifically to the cleaning and shaping of the apical third. The aim of this ex vivo study was to determine the minimum and maximum diameters and shape of the physiological apical foramen in the roots of maxillary and mandibular first molars. A descriptive study was conducted on 89 recently extracted first molars. Roots 3–5 mm from the apex were sectioned and prepared for analysis at 40× magnification. The minimum and maximum diameters of each physiological foramen were measured using the program Motic Images plus 2.0 ML. The shape of the foramina, classified as round, oval or irregular, was determined by the difference between the maximum and minimum diameters. A total of 174 physiological foramina were analyzed. The average of the minimum and maximum diameters was between 0.24–0.33 mm in maxillary first molars and between 0.25–0.33 mm in mandibular first molars. In maxillary molars, the most common shape of the foramen was oval (50%), then irregular (32%), then round (18%). In mandibular molars, the oval shape was also the most frequent (59%), followed by irregular (23%) and round (18%). The findings of this study regarding the morphology of physiological apical foramina in first molars make it easier for the operator to choose the appropriately-sized instruments to perform endodontic therapy successfully. PMID:25937698

  13. Limited elimination of two viruses by cryotherapy of pelargonium apices related to virus distribution.

    Science.gov (United States)

    Gallard, A; Mallet, R; Chevalier, M; Grapin, A

    2011-01-01

    The possibility of eradicating the pelargonium flower break virus (PFBV) and pelargonium line pattern virus (PLPV) by cryotherapy of axillary shoot apices was investigated using five Pelargonium cultivars. Viruses were detected by DAS-ELISA and their location was determined by immunolocalization. Apex culture did not permit elimination of PFBV and only 15 percent regenerated plants of 'Stellar Artic' cultivar were ELISA PLPV-negative. Plants regenerated from cryotherapy-treated apices were tested by DAS-ELISA after a 3-month in vitro culture period. Viruses were not detected in 25 percent and 50 percent of the plants tested for PFBV and PLPV, respectively. However, immunolocalization carried out on apices originating from cryopreserved shoot tips sampled from DAS-ELISA negative plants showed that they were still virus-infected. Using immunolocalization, PFBV and PLPV could be detected in Pelargonium apices, even in the meristematic dome. However, viral particles were more numerous in basal zone cells than in meristematic cells. Our results demonstrate that PFBV and PLPV are present within meristematic cells and that cryopreservation can partly reduce the quantity of these viruses in Pelargonium plants but not eliminate them totally. Additional knowledge on localization and behaviour of viruses during cryopreservation is essential to optimize cryotherapy and plant genetic resource management.

  14. Assessment of the nonoperated root after apical surgery of the other root in mandibular molars

    DEFF Research Database (Denmark)

    Kraus, Riccardo D; von Arx, Thomas; Gfeller, David;

    2015-01-01

    INTRODUCTION: If a surgical approach is chosen to treat a multirooted tooth affected by persistent periapical pathosis, usually only the affected roots are operated on. The present study assessed the periapical status of the nonoperated root 5 years after apical surgery of the other root in mandi...

  15. Effects of ADH on the apical and basolateral membranes of toad urinary bladder epithelial cells.

    Science.gov (United States)

    Donaldson, P J; Leader, J P

    1993-11-01

    Short-circuited urinary bladders from Bufo marinus were supported on their apical surface by an agar mounting method and impaled with microelectrodes via their basolateral membrane. This arrangement provided stable and long-lasting impalements of epithelial cells and yielded reliable membrane potentials and voltage divider ratios (Ra/Rb), where Ra and Rb are apical and basolateral membrane resistances respectively. The membrane potential under short-circuit conditions (Vsc) was -51.4 +/- 2.2 mV (n = 59), while under open-circuit conditions apical membrane potential (Va) and basolateral membrane potential (Vb) were -31.0 +/- 2.4 and 59.5 +/- 2.4 mV, respectively. This yields a "well-shaped" potential profile across the toad urinary bladder, where Va is inversely related to the rate of transport, Isc. Antidiuretic hormone (ADH) produced a hyperpolarisation of Vsc and Vb but had no significant effect on Va. In addition, Ra/Rb was significantly increased by ADH (4.6 +/- 0.5 to 10.2 +/- 3.6). Calculation of individual membrane resistances following the addition of amiloride showed that ADH produced a parallel decrease in Ra and Rb membrane resistance, with the observed increase in Ra/Rb being due to a greater percentage decrease in Rb than in Ra. The ability of ADH to effect parallel changes in apical and basolateral membrane conductance helps to maintain a constant cellular volume despite an increase in transepithelial transport. PMID:8309781

  16. Ultrasonic root-end preparation in apical surgery : a prospective randomized study

    NARCIS (Netherlands)

    de Lange, Jan; Putters, Thomas; Baas, Erik M.; van Ingen, Johan M.

    2007-01-01

    Objective. The purpose of this study was to evaluate the potential benefit of an ultrasonic device in apical surgery on the outcome of treatment. Study design. A randomized prospective design was used in a standardized treatment protocol. Patients were allocated to treatment with an ultrasonic devic

  17. Dual roles of Notch in regulation of apically restricted mitosis and apicobasal polarity of neuroepithelial cells.

    Science.gov (United States)

    Ohata, Shinya; Aoki, Ryo; Kinoshita, Shigeharu; Yamaguchi, Masahiro; Tsuruoka-Kinoshita, Sachiko; Tanaka, Hideomi; Wada, Hironori; Watabe, Shugo; Tsuboi, Takashi; Masai, Ichiro; Okamoto, Hitoshi

    2011-01-27

    How the mitosis of neuroepithelial stem cells is restricted to the apical ventricular area remains unclear. In zebrafish, the mosaic eyes(rw306) (moe/epb41l5(rw306)) mutation disrupts the interaction between the putative adaptor protein Moe and the apicobasal polarity regulator Crumbs (Crb), and impairs the maintenance of neuroepithelial apicobasal polarity. While Crb interacts directly with Notch and inhibits its activity, Moe reverses this inhibition. In the moe(rw306) hindbrain, Notch activity is significantly reduced, and the number of cells that proliferate basally away from the apical area is increased. Surprisingly, activation of Notch in the moe(rw306) mutant rescues not only the basally localized proliferation but also the aberrant neuroepithelial apicobasal polarity. We present evidence that the Crb⋅Moe complex and Notch play key roles in a positive feedback loop to maintain the apicobasal polarity and the apical-high basal-low gradient of Notch activity in neuroepithelial cells, both of which are essential for their apically restricted mitosis. PMID:21262462

  18. Cone beam computed tomography study of apical root resorption induced by Herbst appliance

    Science.gov (United States)

    SCHWARTZ, João Paulo; RAVELI, Taísa Boamorte; ALMEIDA, Kélei Cristina de Mathias; SCHWARTZ-FILHO, Humberto Osvaldo; RAVELI, Dirceu Barnabé

    2015-01-01

    Objective This study evaluated the frequency of root resorption during the orthodontic treatment with Herbst appliance by Cone Beam Computed Tomography (CBCT). Material and Methods The sample comprised 23 patients (11 men, 12 women; mean ages 15.76±1.75 years) with Class II division 1 malocclusion, treated with Herbst appliance. CBCT was obtained before treatment (T0) and after Herbst treatment (T1). All the dental roots, except third molars, were evaluated, and apical root resorption was determined using the axial guided navigation method. Paired t-tests and Wilcoxon T Test were used to compare the dependent samples in parametric and nonparametric cases, respectively. Chi-Square Test with Yates’ correction was used to evaluate the relationship between apical root resorption and gender. Results were considered at a significance level of 5%. Results Apical resorption was detected by CBCT in 57.96% of 980 roots that underwent Herbst appliance treatment. All patients had minimal resorption and there was no statistical significance between the genders. Conclusion CBCT three-dimensional evaluation showed association between Herbst appliance and minimal apical root resorption, mostly in the anchoring teeth, without clinical significance. PMID:26537718

  19. A systematic analysis of neonatal mouse heart regeneration after apical resection.

    Science.gov (United States)

    Bryant, Donald Marion; O'Meara, Caitlin Claire; Ho, Nhi Ngoc; Gannon, Joseph; Cai, Lei; Lee, Richard Theodore

    2015-02-01

    The finding that neonatal mice are able to regenerate myocardium after apical resection has recently been questioned. We determined if heart regeneration is influenced by the size of cardiac resection and whether surgical retraction of the ventricular apex results in an increase in cardiomyocyte cell cycle activity. We performed moderate or large apical ventricular resections on neonatal mice and quantified scar infiltration into the left ventricular wall at 21 days post-surgery. Moderately resected hearts had 15±2% of the wall infiltrated by a collagen scar; significantly greater scar infiltration (23±4%) was observed in hearts with large resections. Resected hearts had higher levels of cardiomyocyte cell cycle activity relative to sham hearts. Surgically retracting the ventricle often resulted in fibrosis and induced cardiomyocyte cell cycle activity that were comparable to that of resected hearts. We conclude that apical resection in neonatal mice induces cardiomyocyte cell cycle activity and neomyogenesis, although scarring can occur. Surgical technique and definition of approach to assessing the extent of regeneration are both critical when using the neonatal mouse apical resection model.

  20. Sugar demand, not auxin, is the initial regulator of apical dominance.

    Science.gov (United States)

    Mason, Michael G; Ross, John J; Babst, Benjamin A; Wienclaw, Brittany N; Beveridge, Christine A

    2014-04-22

    For almost a century the plant hormone auxin has been central to theories on apical dominance, whereby the growing shoot tip suppresses the growth of the axillary buds below. According to the classic model, the auxin indole-3-acetic acid is produced in the shoot tip and transported down the stem, where it inhibits bud growth. We report here that the initiation of bud growth after shoot tip loss cannot be dependent on apical auxin supply because we observe bud release up to 24 h before changes in auxin content in the adjacent stem. After the loss of the shoot tip, sugars are rapidly redistributed over large distances and accumulate in axillary buds within a timeframe that correlates with bud release. Moreover, artificially increasing sucrose levels in plants represses the expression of BRANCHED1 (BRC1), the key transcriptional regulator responsible for maintaining bud dormancy, and results in rapid bud release. An enhancement in sugar supply is both necessary and sufficient for suppressed buds to be released from apical dominance. Our data support a theory of apical dominance whereby the shoot tip's strong demand for sugars inhibits axillary bud outgrowth by limiting the amount of sugar translocated to those buds.

  1. Deep-apical tubules: dynamic lipid-raft microdomains in the brush-border region of enterocytes

    DEFF Research Database (Denmark)

    Hansen, Gert H; Pedersen, Jens; Niels-Christiansen, Lise-Lotte;

    2003-01-01

    microdomains. Deep-apical tubules were positioned close to the actin rootlets of adjacent microvilli in the terminal web region, which had a diameter of 50-100 nm, and penetrated up to 1 microm into the cytoplasm. Markers for transcytosis, IgA and the polymeric immunoglobulin receptor, as well as the resident...... lipid raft-containing compartments, but little is otherwise known about these raft microdomains. We therefore studied in closer detail apical lipid-raft compartments in enterocytes by immunogold electron microscopy and biochemical analyses. Novel membrane structures, deep-apical tubules, were visualized...... brush-border enzyme aminopeptidase N, were present in these deep-apical tubules. We propose that deep-apical tubules are a specialized lipid-raft microdomain in the brush-border region functioning as a hub in membrane trafficking at the brush border. In addition, the sensitivity to cholesterol depletion...

  2. CASE OF DIAGNOSIS OF APICAL FORM OF HYPERTROPHIC CARDIOMYOPATHY WITH A PATIENT WITH PROGRESSIVE ANGINA CLINIC

    Directory of Open Access Journals (Sweden)

    N. S. Krylova

    2014-01-01

    Full Text Available Objective of work: to describe the apical form of hypertrophic cardiomyopathy (AFHC developing under the "mask" of the ischemic heart disease not diagnosed for a long period.Materials and methods. Patient B., 73 y.o., female, was brought to the cardiology department with complains of severe pressing pain behind the breastbone caused with no apparent reason and lasting for over 4 hours. The following examination of the patient was performed: electrocardiography (ECG, echocardiography (EchoCG, Holter ECG monitoring, coronary angiography (CAG, ventriculography.Results. The final diagnosis for the patient was set on the basis of the following readings: ECG data (basic rhythm – atrial fibrillation, left ventricle (LV hypertrophy, negative T-waves in leads V1–6, ST segment depression up to 1–2 mm in leads V4–6, EchoCG (hypertrophy of apical segments of the LV with decreasing of its cavity, moderate dilatation of the left atrium, intraventricular obstruction in the apical third of the LV with the maximum pressure gradient of up to 48 mm Hg., CAG (stenotic lesions of coronary arteries were found, ventriculography (LV volume is not increased, no violations of local contractility, narrowing of the LV cavity in the lower third is observed with thinning in the apex, which indicatesexpressed apical hypertrophy of the LV myocard. AFHC, apical form with moderate obstruction in the lower third of the left ventricle. Stress angina syndrome. CAG and ventriculography were main diagnostic methods that allowed setting the final diagnosis.Conclusion. The clinical case sets forth the peculiarities of diagnostics, therapy, and post-therapy management of patients with this form of AFHC.

  3. CASE OF DIAGNOSIS OF APICAL FORM OF HYPERTROPHIC CARDIOMYOPATHY WITH A PATIENT WITH PROGRESSIVE ANGINA CLINIC

    Directory of Open Access Journals (Sweden)

    N. S. Krylova

    2015-01-01

    Full Text Available Objective of work: to describe the apical form of hypertrophic cardiomyopathy (AFHC developing under the "mask" of the ischemic heart disease not diagnosed for a long period.Materials and methods. Patient B., 73 y.o., female, was brought to the cardiology department with complains of severe pressing pain behind the breastbone caused with no apparent reason and lasting for over 4 hours. The following examination of the patient was performed: electrocardiography (ECG, echocardiography (EchoCG, Holter ECG monitoring, coronary angiography (CAG, ventriculography.Results. The final diagnosis for the patient was set on the basis of the following readings: ECG data (basic rhythm – atrial fibrillation, left ventricle (LV hypertrophy, negative T-waves in leads V1–6, ST segment depression up to 1–2 mm in leads V4–6, EchoCG (hypertrophy of apical segments of the LV with decreasing of its cavity, moderate dilatation of the left atrium, intraventricular obstruction in the apical third of the LV with the maximum pressure gradient of up to 48 mm Hg., CAG (stenotic lesions of coronary arteries were found, ventriculography (LV volume is not increased, no violations of local contractility, narrowing of the LV cavity in the lower third is observed with thinning in the apex, which indicatesexpressed apical hypertrophy of the LV myocard. AFHC, apical form with moderate obstruction in the lower third of the left ventricle. Stress angina syndrome. CAG and ventriculography were main diagnostic methods that allowed setting the final diagnosis.Conclusion. The clinical case sets forth the peculiarities of diagnostics, therapy, and post-therapy management of patients with this form of AFHC.

  4. Apical crown technique to model canal roots. A review of the literature.

    Science.gov (United States)

    Tortini, D; Colombo, M; Gagliani, M

    2007-09-01

    The goals of endodontic therapy are to shape and clean the root canal system in order to receive a three-dimensional and hermetic filling of the entire endodontic space. The aim of this review is to analyze the development of the different canal shaping techniques from the manual stainless-steel instruments to the recently developed rotary Ni-Ti systems. The need to provide instruments of a suitable size to reach the apex of curved root canals drove the development of preparation techniques with a greater focus on the apical part. The Crown-Down technique involves the widening of the canal orifices with Gates-Glidden drills followed by the incremental removal of organic canal contents proceeding from the canal orifice to the apical portion using manual files. Files are used from larger to smaller with no apical pressure. Nevertheless, the term ''Crown-Down'' does not define the technique in the strictest sense, nor does it provide a specific sequence for the use of instruments, but rather defines a way to use the instruments. The preparation of root canals has been revolutionised by the development of Ni-Ti alloys. The features of this alloy give instruments profound flexibility and allow the manufacture of more tapered instruments compared with traditional stainless-steel instruments. In the second part of this review, numerous examples are provided concerning the comparison between different Ni-Ti systems and their techniques for use. A Crown-Down approach provides certain advantages including early organic debris removal, the creation of a large reservoir for irrigating solutions, a straighter access to the apical region of curved canals, and greater precision with regard to the exact working length and apical size.

  5. Morphology of bacterial flora in root canals associated with apical abscesses

    Institute of Scientific and Technical Information of China (English)

    Guo Huijie; Gao Chengzhi; Zhang Chengfei; Zheng Shuying; Yue Lin

    2014-01-01

    Background Apical abscess is an inflammatory process in the peri-radicular tissues caused by biofllms in the necrotic root canal systems.Therefore,a comprehensive analysis of the bacterial colonization is required for a better understanding of the pathogenesis.This study aimed to investigate the patterns of bacterial infection of root canals of teeth with apical abscesses and to determine whether histological and microbiological findings correlated with clinical conditions.Methods Eighteen samples from 18 teeth with apical pathological lesions were analyzed.Nine patients with acute apical abscesses experienced severe pain,and nine patients were asymptomatic with a sinus tract.After extraction,each affected root was divided into two halves.One half was processed for histobacteriologic analysis and examined using light microscopy,and the other half was analyzed using scanning electron microscopy (SEM) to determine the patterns of microbial colonization of the root canals.Results The appearance of each sample subjected to SEM was consistent with the histobacteriologic findings despite the presence or absence of clinical symptoms.Intraradicular biofilms comprising cocci,rods,and/or filaments of amorphous materials were observed in the apical third of the main root canals in all samples.The bacterial biofilms covering the main root canal walls also penetrated the dentinal tubules to varying depths.The morphologies of biofilms varied,and a unique pattern of intraradicular infection was not identified.Conclusion Intraradicular infections formed complex and variable multispecies biofilms and their presence did not correlate with clinical symptoms.

  6. Evaluation of the endodontic apical seal after post insertion by synchrotron radiation microtomography

    International Nuclear Information System (INIS)

    The commonly used methods for evaluating the endodontic apical seal, such as longitudinal and transversal section and diaphanization, show some operative difficulties and intrinsic limitation. This study suggests and describes a new method of analysis using a synchrotron radiation microtomography to analyse the root apex after post insertion, creating a three-dimensional image and analysing sections of the specimen every 5μm. The study was performed at SYRMEP beam line at the Electra Synchrotron in Trieste using monochromatic X-rays of 32KeV. Eleven monoradicular teeth were prepared using NiTi GT Rotary files instruments to an apical size 20 with conicity .06 and divided in four groups: in G1 (n=4) and G2 (n=2), the specimens were endodontically filled with guttapercha and a zinc-oxide sealer, in G3 (n=3) and G4 (n=2) guttapercha and a silicon-based sealer were used. An endodontic post was inserted in specimens of groups 1 and 3 following the manufacturer's instructions. Specimens were analysed using monochromatic X-rays of 32KeV. A CCD detector with pixel dimension pf 5x5μm2 was used for the acquisition process. Seven hundred and twenty projections were performed over 180o range using a high-resolution rotator. The projections were reconstructed using standard algorithms for tomographic reconstruction. The apical infiltration was evaluated by verifying if black spots were detectable on the images. The specimens of groups 3 and 4 showed a better apical seal than the ones of groups 1 and 2. Post insertion, when a ZOE-based sealer is used, increases the apical gap even if it does not seem to be clinically relevant and sufficient to be a cause of endodontic failure. The new method for analysis appeared to be effective to detect small defects in endodontic obturation, analysing guttapercha-sealer and sealer-dentin interfaces

  7. Isolation of radio-iodinated apical and basal-lateral plasma membranes of toad bladder epithelium.

    Science.gov (United States)

    Rodriguez, H J; Edelman, I S

    1979-04-01

    The apical and basal-lateral plasma membranes of toad bladder epithelium were radio-iodinated with the glucose-glucose oxidase-lactoperoxidase system. The covalently bound radio iodine was used as a marker during subcellular fractionation and membrane isolation. Homogenization conditions that ensured rupture of more than 80% of the cells without substantial nuclear damage were defined by Normarski optics. The nuclei were separated by differential centrifugation and the apical and basal-lateral components were resolved by differential and sucrose density gradient centrifugation. The apical components yielded two radioactive bands that were identified as glycocalyx and plasma membrane labeled with 125I. The basal-lateral components yielded a hetero-disperse pattern made up of at least 3 radioactive bands, but the bulk of the activity of ouabain-sensitive ATPase comigrated with only one of these bands. The mitochondia, identified by assays for cytochrome oxidase and NADH cytochrome c reductase activities, were separated from the radio-iodine labeled by centrifugation in sucrose density gradients under isokinetic conditions. The labeled glycocalyx and the slowly migrating components of basal-lateral labeling were separated from the radio-iodinated membranes by centrifugation at 100,000 x g x 1 hr after removal of the mitochrondria by the isokinetic method. The labeled membranes were then subjected to ultracentrifugation in sucrose density gradients under isopycnic conditions; the basal-lateral membranes containing ouabain-sensitive ATP-ase were well resolved from the apical membranes by this method. These results provide a relatively rapid method of attaining partial purification of the apical and basal-lateral plasma membranes of toad bladder epithelium. PMID:222911

  8. Activation of an apical Cl- conductance by Ca2+ ionophores in cystic fibrosis airway epithelia.

    Science.gov (United States)

    Willumsen, N J; Boucher, R C

    1989-02-01

    Cystic fibrosis (CF) airway epithelia express a defect in adenosine 3',5'-cyclic monophosphate (cAMP)-dependent regulation of apical membrane Cl- channels. Recent patch-clamp studies have raised the possibility that Ca2+ -dependent mechanisms for the activation of Cl- secretion may be preserved in CF airway epithelia. To determine 1) whether intact normal (N1) and CF airway epithelia exhibit a Ca2+ -dependent mechanism for activation of Cl- secretion and 2) whether Ca2+ -dependent mechanism for activation of Cl- secretion and 2) whether Ca2+ -dependent mechanisms initiate Cl- secretion via activation of an apical membrane Cl- conductance (GCl-), nasal epithelia from N1 and CF subjects were cultured on collagen membranes, and responses to isoproterenol or Ca2- ionophores [A23187 10(-6) M; ionomycin (10(-5)M)] were measured with transepithelial and intracellular techniques. Isoproterenol induced activation of an apical membrane GCl- in N1 cultures but was ineffective in CF. In contrast, in both N1 and CF amiloride-pretreated cultures, A23187 induced an increase in the equivalent short-circuit current that was associated with an activation of an apical membrane Gc1- and was bumetanide inhibitable. A23187 addition during superfusion of the lumen with a low Cl- (3 mM) solution reduced intracellular Cl- activity of CF cells. A Ca2+ ionophore of different selectivity properties, ionomycin, was also an effective Cl- secretagogue in both N1 and CF cultures. We conclude that 1) the A23187 induced Cl- secretion via activation of an apical GCl- in N1 human nasal epithelium, and 2) in contrast to an isoproterenol-dependent path, a Ca2+ -dependent path for GCl- activation is preserved in CF epithelia. PMID:2465689

  9. CO2 laser on apical seal of retrofilled teeth

    Science.gov (United States)

    Aun, Carlos E.; Gavini, Giulio; Clasen, Naya F.; Silva Kfouri, Luciana

    1997-05-01

    The CO2 laser has been suggested for occlusion of dentinal tubuli and sterilization of the beveled root surfaces, avoiding degrees of irritants from the root canal system into periapical tissues. This study has evaluated marginal leakage in 40 human single rooted teeth divided into 4 groups of 8 teeth which received retrofillings, and 2 control groups of 4 teeth each. Group A: Super EBA; group B: Super EBA and CO2 laser irradiation; group C: Glass Ionomer Cement; group D: Glass ionomer Cement and laser; group E: positive control; group F: negative control. In groups B and D the power set was 2 watts, 20 msec, with a CT3105 ceramic point. Teeth were placed in 5 percent methylene blue dye for 24 hs and the dye penetration was lower in B. The higher penetration was seen in C. Analysis of variance found statistical difference between groups. In this study the laser irradiation was able to change the amount of dye penetration. It can be assumed that Super EBA and Glass Ionomer Cement have their sealing abilities improved by laser irradiation.

  10. Human-computer interface incorporating personal and application domains

    Science.gov (United States)

    Anderson, Thomas G.

    2011-03-29

    The present invention provides a human-computer interface. The interface includes provision of an application domain, for example corresponding to a three-dimensional application. The user is allowed to navigate and interact with the application domain. The interface also includes a personal domain, offering the user controls and interaction distinct from the application domain. The separation into two domains allows the most suitable interface methods in each: for example, three-dimensional navigation in the application domain, and two- or three-dimensional controls in the personal domain. Transitions between the application domain and the personal domain are under control of the user, and the transition method is substantially independent of the navigation in the application domain. For example, the user can fly through a three-dimensional application domain, and always move to the personal domain by moving a cursor near one extreme of the display.

  11. Human-computer interface incorporating personal and application domains

    Science.gov (United States)

    Anderson, Thomas G.

    2004-04-20

    The present invention provides a human-computer interface. The interface includes provision of an application domain, for example corresponding to a three-dimensional application. The user is allowed to navigate and interact with the application domain. The interface also includes a personal domain, offering the user controls and interaction distinct from the application domain. The separation into two domains allows the most suitable interface methods in each: for example, three-dimensional navigation in the application domain, and two- or three-dimensional controls in the personal domain. Transitions between the application domain and the personal domain are under control of the user, and the transition method is substantially independent of the navigation in the application domain. For example, the user can fly through a three-dimensional application domain, and always move to the personal domain by moving a cursor near one extreme of the display.

  12. Interaction of the bovine papillomavirus type 1 E2 transcriptional control protein with the viral enhancer: purification of the DNA-binding domain and analysis of its contact points with DNA.

    OpenAIRE

    Moskaluk, C A; Bastia, D

    1988-01-01

    The E2 gene of bovine papillomavirus type 1 positively and negatively regulates the transcriptional enhancer located in the long control region of the viral genome. The DNA-binding domain of the E2 gene product was suspected to interact with the DNA sequence motif ACCN6GGT. We have shown that the carboxy-terminal 126 amino acids of the E2 protein constitute the DNA-binding domain. In this paper we described the expression of the E2 carboxy terminus in Escherichia coli and its subsequent purif...

  13. Crystal and solution studies of the "Plus-C" odorant-binding protein 48 from Anopheles gambiae: control of binding specificity through three-dimensional domain swapping.

    Science.gov (United States)

    Tsitsanou, Katerina E; Drakou, Christina E; Thireou, Trias; Vitlin Gruber, Anna; Kythreoti, Georgia; Azem, Abdussalam; Fessas, Dimitrios; Eliopoulos, Elias; Iatrou, Kostas; Zographos, Spyros E

    2013-11-15

    Much physiological and behavioral evidence has been provided suggesting that insect odorant-binding proteins (OBPs) are indispensable for odorant recognition and thus are appealing targets for structure-based discovery and design of novel host-seeking disruptors. Despite the fact that more than 60 putative OBP-encoding genes have been identified in the malaria vector Anopheles gambiae, the crystal structures of only six of them are known. It is therefore clear that OBP structure determination constitutes the bottleneck for structure-based approaches to mosquito repellent/attractant discovery. Here, we describe the three-dimensional structure of an A. gambiae "Plus-C" group OBP (AgamOBP48), which exhibits the second highest expression levels in female antennae. This structure represents the first example of a three-dimensional domain-swapped dimer in dipteran species. A combined binding site is formed at the dimer interface by equal contribution of each monomer. Structural comparisons with the monomeric AgamOBP47 revealed that the major structural difference between the two Plus-C proteins localizes in their N- and C-terminal regions, and their concerted conformational change may account for monomer-swapped dimer conversion and furthermore the formation of novel binding pockets. Using a combination of gel filtration chromatography, differential scanning calorimetry, and analytical ultracentrifugation, we demonstrate the AgamOBP48 dimerization in solution. Eventually, molecular modeling calculations were used to predict the binding mode of the most potent synthetic ligand of AgamOBP48 known so far, discovered by ligand- and structure-based virtual screening. The structure-aided identification of multiple OBP binders represents a powerful tool to be employed in the effort to control transmission of the vector-borne diseases. PMID:24097978

  14. 根管-根尖周复合体体外模型的建立%Establishment of an in-vitro root canal-apical complex model

    Institute of Scientific and Technical Information of China (English)

    王容; 钟晓波

    2014-01-01

    Objective To establish an in-vitro root canal-apical complex model for studying the mechanisms of the infected root canal to apical periodontitis and periapical biofilm .Methods Single rooted premolar extracted for orthodontic ,was sealed in sterile vial containing LB solid medium ,and the culture medium covered apical thirds .Totally 25 root canal-apical complex models were prepared .Five models were randomly selected for the bacteria detection in periapical by PCR at 1st day .The remained 20 models were randomly subjected to a control group(n=10) and experimental group(n=10) .Extracted teeth were opened in experimental group and control group with no treatment .All models were exposed in air .At 21st day ,bacteria were detected through PCR in root canal and apical;endotoxin content in apical was assayed by chromogenic end-point limulus test .Results In apical ,bacteria was not found in all groups ,but not for the experimental group .The mean endotoxin content was (8 .913 ± 0 .614)EU/mL in control group and (10 .525 ± 0 .981)EU/mL in experimental group .The endotoxin content was increased significantly in experimental group ,when compared with control group(P<0 .01) .Conclusion Root canal-apical complex was established in vitro through this method .Bac-teria was not easy to reach the apical when the infected root canal was not disturbed .Bacteria in the infected root canal caused apical periodontitis through the secretion of virulence factors such as endotoxin .%目的:建立根管-根尖周组织复合体体外模型,以此探索感染根管形成根尖周炎及根尖生物膜的可能机制。方法将因正畸减数拔除的健康单根前磨牙密封于盛有LB固体培养基的无菌小瓶内,使牙根的根尖1/3置于培养基中,制备成根管-根尖周复合体体外模型25个。建模后1 d抽取5个模型通过PCR技术检测根尖周组织有无细菌。将余下的20个模型分为对照组(n=10)及实验组(n=10),实验组

  15. APRESS: apical regulatory super system, serotonin, and dopamine interaction

    Directory of Open Access Journals (Sweden)

    Hinz M

    2011-08-01

    Full Text Available Marty Hinz1, Alvin Stein2, Thomas Uncini31Clinical Research, NeuroResearch Clinics, Inc, Cape Coral, FL, USA; 2Stein Orthopedic Associates, Plantation, FL, USA; 3DBS Labs, Duluth, MN, USABackground: The monoamines serotonin and dopamine are known to exist in two separate states: the endogenous state and the competitive inhibition state. The presence of the competitive inhibition state has been known to science for many years, but from a functional standpoint it has been noted in the literature as being "meaningless."Methods: A large database of monoamine transporter response to amino acid precursor administration variations with clinical outcomes was accumulated. In the process, a new organic cation transporter (OCT model has been published, and OCT functional status determination along with amino acid precursor manipulation methods have been invented and refined.Results: Methodology was developed whereby manipulation of the OCT, in the competitive inhibition state, is carried out in a predictable manner. This, in turn, has disproved the long-held assertion that the monoamine competitive inhibition state is functionally meaningless.Conclusion: The most significant aspect of this paper is the documentation of newly recognized relationships between serotonin and dopamine. When transport of serotonin and dopamine are both in the competitive inhibition state, manipulation of the concentrations of one will lead to predictable changes in concentrations of the other. From a functional standpoint, processes regulated and controlled by changes to only serotonin can now be controlled by changes to dopamine, and vice versa, in a predictable manner.Keywords: catecholamine, monoamine, competitive inhibition state

  16. The local-global dimension in cognitive control after left lateral prefrontal cortex damage: Evidence from the verbal and the non-verbal domain

    Directory of Open Access Journals (Sweden)

    Eleni Peristeri

    2014-04-01

    Eight patients with damage in the left PFC and twenty age- and education-matched language-unimpaired adults have participated in the study. Non-verbal tasks included an online Global-Local Identification task (designed after Navon, 1977 asking from participants to identify global geometrical shapes, which were made up of smaller (local geometrical configurations while inhibiting local ones, and vice versa. In congruent trials, local and global shapes coincided whereas in incongruent trials they did not. Apart from the local and global condition, the task included a mixed local-global condition, in which participants were asked to identify global and local shapes interchangeably. Participants’ updating functions were independently measured by an online 2-back digit task where individuals were presented with digit sequences and were asked to respond by pressing a pre-specified key once a digit matched the digit occurring two digits earlier. The study also involved four online language tasks: (a a task testing the interpretation of pronouns (Peristeri & Tsimpli, 2013 in globally ambiguous sentential contexts, (b a task testing the interpretation of homophones in sentences requiring global processing, (c a task testing the participants’ sensitivity to local, grammatical gender conflicts of single words in a picture-word interference task, and, (d a task testing participants’ sensitivity to local orthographic violations in the stems and suffixes of single words in a semantic judgment task. Results In the Global-Local Identification task, LPFC-damaged patients with non-fluent aphasia performed more poorly in both accuracy (42% correct and RTs on the local incongruent trials—where identification of the local shape presupposed inhibition of the global configuration—than any other global incongruent or congruent category. Controls were slower (but accurate in local incongruent trials. On the other hand, PFC-damaged patients (along with controls performed at

  17. Immunohistochemical features of the granulation tissue structure in the primary and secondary apical periodontitis

    Directory of Open Access Journals (Sweden)

    Gritsenko P.I.

    2015-03-01

    Full Text Available Background The search of criteria of differential enzymatic activity of cyclooxygenase-2 and matrix metalloproteinases immunocompetent cells of granulomas in the primary and secondary apical periodontitis (AP provides information about the features of lesions of periodontal stromal component, and it can be used as the basis for future therapeutic intervention. Objective. The purpose of this study was to compare the qualitative and quantitative characteristics of the cellular composition of granulation tissue, which formed during primary and secondary apical periodontitis; comparison of morphological characteristics of the structure apical granuloma with immunohistochemical indicators of markers expression of cluster of differentiation CD3, CD4, CD8, CD68, CD138, CD20 and cyclooxygenase-2 and matrix metalloproteinase 9. Methods. The study included 59 patients aged 18 to 50 years with apical periodontitis. Patients were divided into 2 clinical group: 1 – with primary periodontitis and 2 – with secondary periodontitis. For morphological studies using peryapikalnoyi granulation tissue biopsies. Results. Significant differences were found for the fractions of CD4+ T helper cells (p=0,034, r=0,321, CD20+ mature B lymphocytes (p=0,001, r=0,671, CD68+ macrophages (p=0,011, r=0,684 and CD138+ plasma cells (p=0,002, r=0,645. And, also likely decrease in the ratio of CD4+/CD8+ (p=0,002, r=0,645, by reducing the fraction of CD4+ T-helper cells, against reducing the number of leukocytes, expression of MMP-9 (p=0,04, r=0,302 and COX-2 (p=0,013, r=0,321 with secondary apical periodontitis, compared to the primary periodontitis. Conclusion. Disease progression and the beginning of the destruction of bone tissue with the formation of granulation tissue is the result of abnormal immune responses, III and IV type hypersensitivity reactions, with the formation of immune granulomas. Citation: Gritsenko PI, Samojlenko AV, Shpon’ka IS, Poslavska

  18. Asociación entre niveles de TNF-α en fluido crevicular gingival de dientes con periodontitis apical asintomática Levels of TNF-α increase in gingival crevicular fluid of teeth with asymptomatic apical periodontitis

    Directory of Open Access Journals (Sweden)

    M Garrido Flores

    2011-12-01

    Full Text Available Introducción: Como consecuencia de necrosis pulpar séptica, el ingreso de productos bacterianos en el periápice induce la producción de citoquinas pro-inflamatorias como el Factor de Necrosis Tumoral (TNF- a, que entre otras funciones participa en la diferenciación y activación de los osteoclastos para inducir reabsorción ósea, fenómeno característico de la periodontitis apical asintomática (PAA. El fluido crevicular gingival (FCG ofrece un gran potencial como fuente de factores asociados con la actividad osteoclástica. El objetivo del presente estudio fue determinar los niveles de TNF- a en FCG de dientes con PAA y controles sanos contralaterales. Métodos: Se incluyeron 14 pacientes en la Clínica de Endodoncia de la Facultad de Odontología de la Universidad de Chile con diagnóstico clínico de PAA y se obtuvieron muestras de FCG con tiras de papel a partir de los dientes afectados y sanos contralaterales por un periodo estandarizado de 30 segundos. Se determinaron las concentraciones de proteínas totales mediante el método del ácido bisciconitico y los niveles de TNF- a, mediante ensayo ELISA. Los datos se analizaron con Test-t pareado utilizando el programa StataV11. Resultados: Se detectaron niveles de TNF- a significativamente mayores en el FCG de dientes con PAA estandarizados, tanto por 30 segundos de toma de muestra como por mg de proteínas totales. Conclusiones: Este estudio provee evidencia preliminar de que los niveles de TNF- a en el FCG reflejan la presencia de PAA y podría ser de utilidad como complemento al diagnóstico clínico y monitoreo del estado de salud o enfermedad de los tejidos perirradiculares.Introduction: As a consequence of septic pulp necrosis, the entry of bacterial products into periapical tissues induces the release of pro-inflammatory cytokines, such as the tumor necrosis factor (TNF- a. This pleiotropic cytokine is involved in the differentiation and activation of osteoclasts to induce bone

  19. Adenovirus entry from the apical surface of polarized epithelia is facilitated by the host innate immune response.

    Directory of Open Access Journals (Sweden)

    Poornima L N Kotha

    2015-03-01

    Full Text Available Prevention of viral-induced respiratory disease begins with an understanding of the factors that increase or decrease susceptibility to viral infection. The primary receptor for most adenoviruses is the coxsackievirus and adenovirus receptor (CAR, a cell-cell adhesion protein normally localized at the basolateral surface of polarized epithelia and involved in neutrophil transepithelial migration. Recently, an alternate isoform of CAR, CAREx8, has been identified at the apical surface of polarized airway epithelia and is implicated in viral infection from the apical surface. We hypothesized that the endogenous role of CAREx8 may be to facilitate host innate immunity. We show that IL-8, a proinflammatory cytokine and a neutrophil chemoattractant, stimulates the protein expression and apical localization of CAREx8 via activation of AKT/S6K and inhibition of GSK3β. Apical CAREx8 tethers infiltrating neutrophils at the apical surface of a polarized epithelium. Moreover, neutrophils present on the apical-epithelial surface enhance adenovirus entry into the epithelium. These findings suggest that adenovirus evolved to co-opt an innate immune response pathway that stimulates the expression of its primary receptor, apical CAREx8, to allow the initial infection the intact epithelium. In addition, CAREx8 is a new target for the development of novel therapeutics for both respiratory inflammatory disease and adenoviral infection.

  20. Structures of PHR Domains from Mus musculus Phr1 (Mycbp2) Explain the Loss-of-Function Mutation (Gly1092 → Glu) of the C. elegans Ortholog RPM-1

    Energy Technology Data Exchange (ETDEWEB)

    Sampathkumar, Parthasarathy; Ozyurt, Sinem A.; Miller, Stacy A.; Bain, Kevin T.; Rutter, Marc E.; Gheyi, Tarun; Abrams, Benjamin; Wang, Yingchun; Atwell, Shane; Luz, John G.; Thompson, Devon A.; Wasserman, Stephen R.; Emtage, J. Spencer; Park, Eun Chan; Rongo, Christopher; Jin, Yishi; Klemke, Richard L.; Sauder, J. Michael; Burley, Stephen K. (Rutgers); (UCSC); (Lilly); (UCSD)

    2010-11-15

    PHR [PAM (protein associated with Myc)-HIW (Highwire)-RPM-1 (regulator of presynaptic morphology 1)] proteins are conserved, large multi-domain E3 ubiquitin ligases with modular architecture. PHR proteins presynaptically control synaptic growth and axon guidance and postsynaptically regulate endocytosis of glutamate receptors. Dysfunction of neuronal ubiquitin-mediated proteasomal degradation is implicated in various neurodegenerative diseases. PHR proteins are characterized by the presence of two PHR domains near the N-terminus, which are essential for proper localization and function. Structures of both the first and second PHR domains of Mus musculus (mouse) Phr1 (MYC binding protein 2, Mycbp2) have been determined, revealing a novel {beta} sandwich fold composed of 11 antiparallel {beta}-strands. Conserved loops decorate the apical side of the first PHR domain (MmPHR1), yielding a distinct conserved surface feature. The surface of the second PHR domain (MmPHR2), in contrast, lacks significant conservation. Importantly, the structure of MmPHR1 provides insights into a loss-of-function mutation, Gly1092 {yields} Glu, observed in the Caenorhabditis elegans ortholog RPM-1.

  1. Cooperative Control of Caspase Recruitment Domain-containing Protein 11 (CARD11) Signaling by an Unusual Array of Redundant Repressive Elements.

    Science.gov (United States)

    Jattani, Rakhi P; Tritapoe, Julia M; Pomerantz, Joel L

    2016-04-15

    Several classes of signaling proteins contain autoinhibitory domains that prevent unwarranted signaling and coordinate the induction of activity in response to external cues. CARD11, a scaffold protein critical for antigen receptor signaling to NF-κB, undergoes autoregulation by a poorly understood inhibitory domain (ID), which keeps CARD11 inactive in the absence of receptor triggering through inhibitory intramolecular interactions. This autoinhibitory strategy makes CARD11 highly susceptible to gain-of-function mutations that are frequently observed in diffuse large B cell lymphoma (DLBCL) and that disrupt ID-mediated autoinhibition, leading to constitutive NF-κB activity, which can promote lymphoma proliferation. Although DLBCL-associated CARD11 mutations in the caspase recruitment domain (CARD), LATCH domain, and coiled coil have been shown to disrupt intramolecular ID binding, surprisingly, no gain-of-function mutations in the ID itself have been reported and validated. In this study, we solve this paradox and report that the CARD11 ID contains an unusual array of four repressive elements that function cooperatively with redundancy to prevent spontaneous NF-κB activation. Our quantitative analysis suggests that potent oncogenic CARD11 mutations must perturb autoinhibition by at least three repressive elements. Our results explain the lack of ID mutations in DLBCL and reveal an unusual autoinhibitory domain structure and strategy for preventing unwarranted scaffold signaling to NF-κB.

  2. Apical Plasma Membrane Proteins and Endolyn-78 Travel through a Subapical Compartment in Polarized WIF-B Hepatocytes

    OpenAIRE

    Ihrke, Gudrun; Martin, Greg V.; Shanks, Michael R.; Schrader, Michael; Schroer, Trina A.; Hubbard, Ann L.

    1998-01-01

    We studied basolateral-to-apical transcytosis of three classes of apical plasma membrane (PM) proteins in polarized hepatic WIF-B cells and then compared it to the endocytic trafficking of basolaterally recycling membrane proteins. We used antibodies to label the basolateral cohort of proteins at the surface of living cells and then followed their trafficking at 37°C by indirect immunofluorescence. The apical PM proteins aminopeptidase N, 5′nucleotidase, and the polymeric IgA receptor were ef...

  3. Filtración apical versus filtración coronal

    OpenAIRE

    Tabares Martínez, Pablo

    2016-01-01

    La filtración del conducto radicular es la principal causa de los fracasos en endodoncia (19). Esta recontaminación puede producirse a través de dos vías principales de filtración que son los orificios coronal y apical. En la actualidad hay controversia entre diferentes autores sobre cuál es la vía de filtración más importante, si la apical (9, 167) o la coronal (4, 76). Existen diversas técnicas de obturación y materiales de obturación, entre las que puede elegir el clínico en función de cad...

  4. Micro‐CT analyses of apical enlargement and molar root canal complexity

    DEFF Research Database (Denmark)

    Markvart, M.; Darvann, Tron Andre; Larsen, P.;

    2012-01-01

    Markvart M, Darvann TA, Larsen P, Dalstra M, Kreiborg S, Bjørndal L. Micro‐CT analyses of apical enlargement and molar root canal complexity. International Endodontic Journal, 45, 273–281, 2012. Aim To compare the effectiveness of two rotary hybrid instrumentation techniques with focus on apical...... enlargement in molar teeth and to quantify and visualize spatial details of instrumentation efficacy in root canals of different complexity. Methodology Maxillary and mandibular molar teeth were scanned using X‐ray microcomputed tomography. Root canals were prepared using either a GT/Profile protocol or a Ra......Ce/NiTi protocol. Variables used for evaluation were the following: distance between root canal surfaces before and after preparation (distance after preparation, DAP), percentage of root canal area remaining unprepared and increase in canal volume after preparation. Root canals were classified according to size...

  5. Inadvertent Apical Extrusion of Sodium Hypochlorite with Evaluation by Dental Volumetric Tomography

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    Elif Delve Başer Can

    2015-01-01

    Full Text Available This case report describes the tissue injury caused by inadvertently extruded NaOCl through the apical constriction. A 56-year-old female patient with complaints of pain, swelling, and ecchymosis on the left side of her face was referred to our clinic. The symptoms had emerged following root canal treatment of the maxillary left first premolar, and a soft tissue complication due to apical extrusion of NaOCl was diagnosed. Antibiotics and analgesics were prescribed. DVT images revealed that the buccal root apex had perforated the maxillary bone. The patient was followed up every other day and became asymptomatic on the 10th day. Endodontic therapy was completed with routine procedures. Determining working length precisely and following irrigation protocols meticulously are indispensable to prevent this type of complication. 3D visualization of the affected area may reveal the cause of the incident.

  6. Multiple Apical Radiolucencies and External Cervical Resorption Associated with Varicella Zoster Virus: A Case Report.

    Science.gov (United States)

    Patel, Kreena; Schirru, Elia; Niazi, Sadia; Mitchell, Philip; Mannocci, Francesco

    2016-06-01

    Varicella zoster virus (VZV) is responsible for the primary infection chickenpox. After the initial infection, it remains latent but can reactivate, resulting in shingles (herpes zoster). Previous reports have implicated VZV in the pathogenesis of apical periodontitis, but the involvement of the virus has not been investigated fully. The present case describes a patient who suffered from a severe episode of shingles and subsequently developed periapical radiolucencies of all the teeth in the affected nerve distribution. Molecular and culture techniques showed the presence of VZV DNA in the root canal system in the absence of bacteria. This confirms that VZV can cause localized pulp necrosis and apical periodontitis. The lesions healed after endodontic treatment, implying chemomechanical debridement using sodium hypochlorite irrigation and a calcium hydroxide interim dressing may be effective against the virus. PMID:27133503

  7. Apical ballooning with mid-ventricular obstruction: the many faces of Takotsubo cardiomyopathy.

    Science.gov (United States)

    Spadotto, Veronica; Elmaghawry, Mohamed; Zorzi, Alessandro; Migliore, Federico; Marra, Martina Perazzolo

    2013-01-01

    Takotsubo cardiomyopathy (TTC) is a transient left ventricular dysfunction due to akinesia of the left-ventricular (LV) mid-apical segments (apical ballooning), which can cause severe reduction in LV systolic function. The typical clinical picture of TTC include chest pain, electrocardiographic changes consisting of mild ST-segment elevation followed by diffuse deep T-wave inversion, QTc interval prolongation and mild troponin release in the absence of significant coronary stenoses. The syndrome often affects post-menopausal women and is triggered by sympathetic overstimulation, like intense physical or emotional stress, so that it is called the "broken heart syndrome". Although left-ventricular systolic dysfunction usually fully recovers within few days, heart failure can still complicate the early phase. We report a case of stress-induced cardiomyopathy that had full recovery after 4 weeks of follow up. The main electrocardiographic, angiographic and imaging features are discussed. PMID:24689016

  8. The effect of root preparation technique and instrumentation length on the development of apical root cracks.

    Science.gov (United States)

    Adorno, Carlos G; Yoshioka, Takatomo; Suda, Hideaki

    2009-03-01

    The purpose of this study was to compare the effects of root canal preparation techniques and instrumentation length on the development of apical root cracks. Forty extracted mandibular premolars with straight roots were randomly selected and mounted on resin blocks with simulated periodontal ligaments, and the apex was exposed. The teeth were divided into four groups of 10 teeth each for different canal preparation techniques and instrumentation lengths: group A: step-back preparation (SB) with stainless steel files (SF) using root canal length (RCL) to guide instrumentation length; group B: SB using RCL - 1 mm; group C: crown-down preparation (CD) with Profile using RCL; and group D: CD with PF using RCL - 1 mm. Digital images of the instrumentation sequence were compared for each tooth. Statistical analysis revealed a significant effect of instrumentation length (p 0.05) on the development of apical cracks.

  9. Transcriptional profiling of the pea shoot apical meristem reveals processes underlying its function and maintenance

    Directory of Open Access Journals (Sweden)

    Singh Mohan B

    2008-06-01

    Full Text Available Abstract Background Despite the importance of the shoot apical meristem (SAM in plant development and organ formation, our understanding of the molecular mechanisms controlling its function is limited. Genomic tools have the potential to unravel the molecular mysteries of the SAM, and legume systems are increasingly being used in plant-development studies owing to their unique characteristics such as nitrogen fixation, secondary metabolism, and pod development. Garden pea (Pisum sativum is a well-established classic model species for genetics studies that has been used since the Mendel era. In addition, the availability of a plethora of developmental mutants makes pea an ideal crop legume for genomics studies. This study aims to utilise genomics tools in isolating genes that play potential roles in the regulation of SAM activity. Results In order to identify genes that are differentially expressed in the SAM, we generated 2735 ESTs from three cDNA libraries derived from freshly micro-dissected SAMs from 10-day-old garden peas (Pisum sativum cv Torsdag. Custom-designed oligonucleotide arrays were used to compare the transcriptional profiles of pea SAMs and non-meristematic tissues. A total of 184 and 175 transcripts were significantly up- or down-regulated in the pea SAM, respectively. As expected, close to 61% of the transcripts down-regulated in the SAM were found in the public database, whereas sequences from the same source only comprised 12% of the genes that were expressed at higher levels in the SAM. This highlights the under-representation of transcripts from the meristematic tissues in the current public pea protein database, and demonstrates the utility of our SAM EST collection as an essential genetic resource for revealing further information on the regulation of this developmental process. In addition to unknowns, many of the up-regulated transcripts are known to encode products associated with cell division and proliferation

  10. Uptake and Distribution of Aluminum in Root Apices of Two Rice Varieties under Aluminum Stress

    Directory of Open Access Journals (Sweden)

    MIFTAHUDIN

    2007-09-01

    Full Text Available Aluminum (Al toxicity is the major limiting factor of plant growth and production in acid soils. The target of Al toxicity is the root tip, which affects mainly on root growth inhibition. The aim of this research was to study the uptake and distribution of Al in root apices of two rice varieties IR64 (Al-sensitive and Krowal (Al-tolerant, which were grown on nutrient solution containing 0, 15, 30, 45, and 60 ppm of Al. The root growth was significantly inhibited in both rice varieties at as low as 15 ppm Al concentration. The adventive roots of both varieties showed stunted growth in respons to Al stress. There was no difference in root growth inhibition between both rice varieties as well as among Al concentrations. Al uptake on root apices was qualitatively and quantitatively analyzed. Histochemical staining of roots using hematoxylin showed dark purple color on 1 mm region of Al-treated root apices. Rice var. IR 64 tended to take up more Al in root tip than Krowal did. However, there was no statistically significant difference (p = 0.176 in root Al content of both varieties in response to different concentration and period of Al treatments. Al distribution in root apices was found in the epidermal and subepidermal region in both rice varieties. Based on those results, rice var. Krowal that was previously grouped as Al-tolerant variety has similar root growth and physiological response to Al stress as compared to Al-sensitive variety IR64.

  11. Effects of Long-term Right Ventricular Apical Pacing on Left Ventricular Remodeling and Cardiac Function

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Objective: To investigate the impacts of long-term right ventricular apical pacing on the ventricular remodeling and cardiac functions of patients with high-grade and third-degree atrioventricular blockage with normal heart structures and cardiac functions. In addition, we provide many evidences for choosing an optimal electrode implantation site.Methods: Study participants included patients who were admitted for pacemaker replacements and revisited for examinations of implanted pacemakers at outpatient. Pa...

  12. Apical groove type and molecular phylogeny suggests reclassification of Cochlodinium geminatum as Polykrikos geminatum.

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    Dajun Qiu

    Full Text Available Traditionally Cocholodinium and Gymnodinium sensu lato clade are distinguished based on the cingulum turn number, which has been increasingly recognized to be inadequate for Gymnodiniales genus classification. This has been improved by the combination of the apical groove characteristics and molecular phylogeny, which has led to the erection of several new genera (Takayama, Akashiwo, Karenia, and Karlodinium. Taking the apical groove characteristics and molecular phylogeny combined approach, we reexamined the historically taxonomically uncertain species Cochlodinium geminatum that formed massive blooms in Pearl River Estuary, China, in recent years. Samples were collected from a bloom in 2011 for morphological, characteristic pigment, and molecular analyses. We found that the cingulum in this species wraps around the cell body about 1.2 turns on average but can appear under the light microscopy to be >1.5 turns after the cells have been preserved. The shape of its apical groove, however, was stably an open-ended anticlockwise loop of kidney bean shape, similar to that of Polykrikos. Furthermore, the molecular phylogenetic analysis using 18S rRNA-ITS-28S rRNA gene cistron we obtained in this study also consistently placed this species closest to Polykrikos within the Gymnodinium sensu stricto clade and set it far separated from the clade of Cochlodinium. These results suggest that this species should be transferred to Polykrikos as Polykrikos geminatum. Our results reiterate the need to use the combination of apical groove morphology and molecular phylogeny for the classification of species within the genus of Cochlodinium and other Gymnodiniales lineages.

  13. ABA mediates PEG-mediated premature differentiation of root apical meristem in plants

    OpenAIRE

    Ji, Hongtao; Li, Xia

    2014-01-01

    Root apical meristem (RAM) is central for indeterminate growth of plant roots and in sensing environmental stimuli, such as water status. Recently, we reported that PEG8000-simulated mild and moderate osmotic stress induces premature differentiation of RAM, which is a conserved adaptive mechanism in higher plants to cope with water stress. Microarray data analysis revealed that the ABA signaling pathway may be involved in water stress-induced RAM premature differentiation. Here we showed that...

  14. Evaluation of the anatomical alterations of lower molars mesial root?s apical third

    Directory of Open Access Journals (Sweden)

    FRÖNER Izabel Cristina

    1999-01-01

    Full Text Available The anatomical apex of the mesial root of the lower molars presents a morphological complexity related to the number and shape of the root canals as well as of the apical foramen and isthmus presence. The knowledge of the complexity of the endodontic system of the molar root area is essencial to select more carefully the best instrumentation and obturation technique, to obtain a more successful endodontic therapy.

  15. A new approach to supply chain management based on pooling ITIL and APICS Principles and Practices

    Directory of Open Access Journals (Sweden)

    Abdelaali Himi

    2011-07-01

    Full Text Available APICS (Advanced Productivity, Innovation and Competitive Success - The Association for Operations Management is known as the repository providing a set of best practices in Supply Chain Management. The ITIL (Information Technology Infrastructure Library also provides best practices for IT service management. Noting the existence of a similarity between these two standards, this paper identifies the ITIL concepts used in the supply chain context and describe their contributions.

  16. Pseudo-acute myocardial infarction due to transient apical ventricular dysfunction syndrome (Takotsubo syndrome)

    OpenAIRE

    Maciel, Bruno Araújo; Cidrão, Alan Alves de Lima; Sousa, Ítalo Bruno dos Santos; Ferreira, José Adailson da Silva; Messias Neto, Valdevino Pedro

    2013-01-01

    Takotsubo syndrome is characterized by predominantly medial-apical transient left ventricular dysfunction, which is typically triggered by physical or emotional stress. The present article reports the case of a 61-year-old female patient presenting with dizziness, excessive sweating, and sudden state of ill feeling following an episode involving intense emotional stress. The physical examination and electrocardiogram were normal upon admission, but the troponin I and creatine kinase-MB concen...

  17. 24 hour ST segment analysis in transient left ventricular apical ballooning.

    Directory of Open Access Journals (Sweden)

    Frank Bode

    Full Text Available OBJECTIVE: The etiologic basis of transient left ventricular apical ballooning, a novel cardiac syndrome, is not clear. Among the proposed pathomechanisms is coronary vasospasm. Long-term ST segment analysis may detect vasospastic episodes but has not been reported. METHODS: 30 consecutive patients with transient left ventricular apical ballooning, left ventricular dysfunction and normal or near-normal coronary arteries were investigated. A 24-hour Holter ECG was obtained after emergency admission. ST segment analysis was performed automatically in 2 leads and confirmed by visual inspection. Criteria for an ischemic event were: 1. ST elevation or 2. horizontal or down-sloping ST segments ≥1 min duration and ≥100 µV J+80 point deviation corrected for baseline ST-deviation. RESULTS: Patients presented with ST segment elevation (n = 19 and/or T wave inversion (n = 20 on admission ECG. Ejection fraction was 50±12%. No transient ST elevations were observed during Holter ECG analysis. In 3 patients, 8 transient episodes of ST depression were recorded. Durations of episodes varied between 75 s and 790 s (mean 229 s. Maximal ST deviation averaged -191±71 µV. Ischemic burden was -1 to -22 mVs (mean -8 mVs. 27 patients showed no ischemic events. CONCLUSIONS: ST segment analysis of 24 h Holter recordings revealed minor ischemic events in only 10% of patients with transient left ventricular apical ballooning. Overall, ST segment changes were not indicative of recurrent coronary spasm playing a major role in the genesis of transient left ventricular apical ballooning.

  18. Assessment of apically extruded debris and irrigant produced by different nickel-titanium instrument systems

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    Ebru KÜÇÜKYILMAZ

    2015-01-01

    Full Text Available The aim of this study was to evaluate the preparation time and the amounts of apically extruded debris and irrigant using different nickel-titanium instrumentation systems. Forty-five extracted single-rooted mandibular premolar teeth were selected and divided into three groups. The root canals were instrumented according to the manufacturers’ instructions, using a reciprocating single-file system, a single-file rotary system and a multiple-file rotary system. Bidistilled water was used as the irrigant solution. The apically extruded debris and irrigant were collected into preweighed Eppendorf tubes. The amounts of extruded debris and irrigant were assessed with a precision micro-balance. The Eppendorf tubes were incubated at 37°C for 15 days. After the incubation period, they were weighed again to assess the debris extrusion. The time required to prepare the canals was also recorded. The results were statistically analyzed using MANOVA and Bonferroni’s adjustment. Considering the apically extruded debris and irrigant, there were no statistically significant differences among the groups (p > 0.05. The Reciproc group produced the highest debris (0.000632 ± 0.000162 gr and irrigant (0.844587 ± 0.437814 ml extrusion values. While the least extruded debris was observed with OneShape (0,000431 ± 0,000171 gr, the least extruded irrigant was observed with ProTaper system (0.564147 ± 0.370596 ml. Instrumentation was faster using the Reciproc than the other two instruments (70.27 ± 13.38 s (p < 0.05. All of the instrumentation systems used in this study produced apical debris and irrigant extrusion. The reciprocating single-file system tended to produce more debris and irrigant extrusion, compared with the rotary systems. Considering the preparation time, the single-file systems appeared to be advantageous due to their working time.

  19. An investigation on the effects of resection angle on apical sea!

    Directory of Open Access Journals (Sweden)

    Razmi H

    2003-08-01

    Full Text Available Statement of Problem: The goal of a successful endodontic surgery is to establish an adequate seal in apical region. Therefore during surgery, root-end resection is essential for an appropriate situation and proper access."nPurpose: The aim of this study was to determine the most appropriate root-end resection angle to establish adequate apical seal in periapical surgery,"nMaterials and Methods: Forty-five intact extracted human maxillary central incisors were randomly divided into three 15-tooth groups. The root canals were instrumented and then obturated using lateral condensation technique. AM roots were resected at 3mm from apical portion. Angles of root resection for each group were 0, 30 and 45 degrees. Then all teeth surfaces, except the cut ones, were covered with nail polish and immersed in methylen blue for 7 days. After 7 days, nail polish was removed from the surfaces and samples were split in buccolingual direction. Then, dye penetration (mm was measured using a stereozoom microscope (Loupe [X4 magnification] and eye lens. In order to analyze the data, unilateral variance analysis was used."nResults: The values of dye penetration were: 7.23±3.34 (0°, 8.46±3.01(30° and 9.74±4.11 (45°. There"nwas no significant difference between three groups (P>0.05. Conclusion: It is suggested that the angle of root-end resection put a limited effect on apical seal if retrograde cavity depth is increased.

  20. An auxin responsive CLE gene regulates shoot apical meristem development in Arabidopsis

    OpenAIRE

    Guo, Hongyan; Zhang, Wei; Tian, Hainan; Zheng, Kaijie; Dai, Xuemei; Liu, Shanda; Hu, Qingnan; Wang, Xianling; Liu, Bao; Wang, Shucai

    2015-01-01

    Plant hormone auxin regulates most, if not all aspects of plant growth and development, including lateral root formation, organ pattering, apical dominance, and tropisms. Peptide hormones are peptides with hormone activities. Some of the functions of peptide hormones in regulating plant growth and development are similar to that of auxin, however, the relationship between auxin and peptide hormones remains largely unknown. Here we report the identification of OsCLE48, a rice (Oryza sativa) CL...

  1. An auxin responsive CLE gene regulates shoot apical meristem development in Arabidopsis

    OpenAIRE

    Hongyan eGuo; Wei eZhang; Hainan eTian; Kaijie eZheng; Xuemei eDai; Shanda eLiu; Qingnan eHu; Xianling eWang; Bao eLiu; Shucai eWang

    2015-01-01

    Plant hormone auxin regulates most, if not all aspects of plant growth and development, including lateral root formation, organ pattering, apical dominance and tropisms. Peptide hormones are peptides with hormone activities. Some of the functions of peptide hormones in regulating plant growth and development are similar to that of auxin, however, the relationship between auxin and peptide hormones remains largely unknown. Here we report the identification of OsCLE48, a rice (Oryza sativa) CLE...

  2. Expression analysis of Matrix Metalloproteinase-9 in epithelialized and non-epithelialized apical periodontitis lesions

    Science.gov (United States)

    Carneiro, Everdan; Menezes, Renato; Garlet, Gustavo Pompermaier; Garcia, Roberto Brandão; Bramante, Clóvis Monteiro; Figueira, Rita; Sogayar, Mari; Granjeiro, José Mauro

    2009-01-01

    OBJECTIVE To determine the expression of matrix metalloproteinase-9 (MMP-9) in apical periodontitis lesions. STUDY DESIGN Nineteen epithelialized and eighteen non-epithelialized apical periodontitis lesions were collected after periapical surgery. After histological processing, serial sectioning, H&E staining and microscopic analysis, 10 epithelialized and 10 non-epithelialized lesions were selected for immunohistochemical analysis for MMP-9 and CD 68. At least 1/3 of each specimen was frozen at −70°C for further mRNA isolation and reverse transcription into cDNA for Real-Time-PCR procedures. The relative expression of a target gene was determined in comparison with reference genes (GAPDH, HPRT, β-actin and BCRP). RESULTS Polymorphonuclear neutrophils, macrophages and lymphocytes were stained for MMP-9 in both types of lesions, and when present, epithelial cells were also stained. The number and the ratio of MMP-9+/total cells were greater in non-epithelialized than epithelialized lesions (p=0.0001) and showed a positive correlation to CD68+/total cells (p=0.045). No significant differences were observed for MMP-9 mRNA expression between ephithelized and non-ephithelized lesions. However, when compared to healthy periapical ligaments, both types of lesions presented increased MMP-9 expression (p<0.0001). CONCLUSION The present data suggest the participation of several inflammatory cells, mainlly CD68+ cells, in the MMP-9 expression in apical periodontitis lesions. MMP-9 could be actively enroled in the ECM degradation in apical periodontitis lesions. PMID:18926740

  3. Light sheet microscopy for tracking single molecules on the apical surface of living cells.

    Science.gov (United States)

    Li, Yu; Hu, Ying; Cang, Hu

    2013-12-12

    Single particle tracking is a powerful tool to study single molecule dynamics in living biological samples. However, current tracking techniques, which are based mainly on epifluorescence, confocal, or TIRF microscopy, have difficulties in tracking single molecules on the apical surface of a cell. We present here a three-dimensional (3D) single particle tracking technique that is based on prism coupled light-sheet microscopy (PCLSM). This novel design provides a signal-to-noise ratio comparable to confocal microscopy while it has the capability of illuminating at arbitrary depth. We demonstrate tracking of single EGF molcules on the apical surface of live cell membranes from their binding to EGF receptors until they are internalized or photobleached. We found that EGF exhibits multiple diffusion behaviors on live A549 cell membranes. At room temperature, the average diffusion coefficient of EGF on A549 cells was measured to be 0.13 μm(2)/s. Depletion of cellular cholesterol with methyl-β-cyclodextrin leads to a broader distribution of diffusion coefficients and an increase of the average diffusion coefficient at room temperature. This light-sheet based 3D single particle tracking technique solves the technique difficulty of tracking single particles on apical membranes and is able to document the whole "lifetime" of a particle from binding till photobleaching or internalization. PMID:23895420

  4. Diagnosis and planning in apical surgery: use of cone-beam tomography

    Directory of Open Access Journals (Sweden)

    Regina Karla de Pontes Lima

    2010-10-01

    Full Text Available Introduction and objective: The ability to tridimensionally evaluate pathological and anatomical areas, in apical surgery planning, presents a number of advantages. Cone beam computed tomography (CBCT was developed for dental applications. This paper aims to present a literature review on CBCT, highlighting its advantages over both conventional computed tomography (CT and radiography. Moreover, its clinical applications in apical surgery are discussed. Literature review and conclusion: Unlikely CT, CBCT captures a volume of data in a single 360° rotation, providing benefits such as higher accuracy, better resolution, reduced scanning time and reduced radiation dose. In the maxillofacial region, CBCT has been mainly used in the assessment of dento-alveolar pathology and oral traumatology. CBCT provides a better diagnosis and quantitative information on periodontal bone levels than conventional radiography. It has also been used for patients requiring surgical facial reconstruction, orthognathic surgery, dental implants, and more complex tooth extractions. Besides that, it seems to be a significant tool in modern endodontic practice, presenting useful applications in apical surgery.

  5. Apical Extrusion of Debris Produced during Continuous Rotating and Reciprocating Motion

    Science.gov (United States)

    Nevares, Giselle; Xavier, Felipe; Gominho, Luciana; Cavalcanti, Flávia; Cassimiro, Marcely; Romeiro, Kaline; Alvares, Pamella; Queiroz, Gabriela; Sobral, Ana Paula; Gerbi, Marleny; Silveira, Marcia; Albuquerque, Diana

    2015-01-01

    This study aimed to analyse and compare apical extrusion of debris in canals instrumented with systems used in reciprocating and continuous motion. Sixty mandibular premolars were randomly divided into 3 groups (n = 20): the Reciproc (REC), WaveOne (WO), and HyFlex CM (HYF) groups. One Eppendorf tube per tooth was weighed in advance on an analytical balance. The root canals were instrumented according to the manufacturer's instructions, and standardised irrigation with 2.5% sodium hypochlorite was performed to a total volume of 9 mL. After instrumentation, the teeth were removed from the Eppendorf tubes and incubated at 37°C for 15 days to evaporate the liquid. The tubes were weighed again, and the difference between the initial and final weight was calculated to determine the weight of the debris. The data were statistically analysed using the Shapiro-Wilk, Wilcoxon, and Mann-Whitney tests (α = 5%). All systems resulted in the apical extrusion of debris. Reciproc produced significantly more debris than WaveOne (p < 0.05), and both systems produced a greater apical extrusion of debris than HyFlex CM (p < 0.001). Cross section and motion influenced the results, despite tip standardization. PMID:26543896

  6. Master apical file size - smaller or larger: a systematic review of microbial reduction.

    Science.gov (United States)

    Aminoshariae, A; Kulild, J

    2015-11-01

    The purpose of this systematic review was to determine, in patients undergoing root canal treatment, whether apical enlargement of canals affected microbial reduction. A PICO (population, intervention, comparison and outcome) strategy was developed to identify previously published studies dealing with apical size of canal and microbial reduction. The MEDLINE, Embase, Cochrane and PubMed databases were searched. Additionally, the bibliographies of all relevant articles and textbooks were manually searched. Based on inclusion and exclusion criteria, two reviewers independently selected the relevant articles. Due to the variety of methodologies and different techniques used to measure outcome for master apical file enlargement, it was not possible to standardize the research data and to apply a meta-analysis. Seven articles were identified that met the inclusion criteria. Five of the seven articles generally concluded that canal enlargement reduced bioburden in the root canal system. Two articles reported no difference in canals enlarged to size 25 or 40. The results of the systematic review confirmed that more evidence-based research in this area is needed. With the limited information currently available, the best current available clinical evidence suggests that contemporary chemomechanical debridement techniques with canal enlargement techniques do not eliminate bacteria during root canal treatment at any size.

  7. Sample preparation for laser-microdissection of soybean shoot apical meristem

    Directory of Open Access Journals (Sweden)

    Chui E. Wong

    2012-10-01

    Full Text Available The shoot apical meristem houses stem cells responsible for the continuous formation of aerial plant organs including leaves and stems throughout the life of plants. Laser-microdissection in combination with high-throughput technology such as next generation sequencing permits an in-depth analysis of molecular events associated with specific cell type of interest. Sample preparation is the most critical step in ensuring good quality RNA to be extracted from samples following laser-microdissection. Here, we optimized the sample preparation for a major legume crop, soybean. We used Farmer’s solution as a fixative and paraffin as the embedding medium for soybean shoot apical meristem tissue without the use of any specialized equipment. Shorter time for tissue fixation (two days was found to be critical for the preservation of RNA in soybean shoot apical meristem. We further demonstrated the utility of this method for different tissues derived from soybean and rice. The method outlined here shall facilitate studies on crop plants involving laser-microdissection.

  8. Relationship of apical lymph node involvement to survival in resected colon carcinoma.

    Science.gov (United States)

    Malassagne, B; Valleur, P; Serra, J; Sarnacki, S; Galian, A; Hoang, C; Hautefeuille, P

    1993-07-01

    In a prospective study of 197 patients with resected colon carcinoma treated between 1974 and 1985, we explored the relationships between pathologic parameters, and the effect of the latter on survival, to identify the parameter whose systematic measurement would improve the predictive capacity of pathologic staging. Prognostic characteristics were studied by univariate analysis. The results showed significant relationships between the location and number of lymph nodes involved, blood vessel invasion, depth of tumor penetration, and metastases. The five-year survival rates were 45 percent and 17 percent (P < 0.001) for patients without and with apical lymph node involvement, respectively, and 44 percent and 6 percent (P < 0.05) for those with four or less nodes involved and more than four involved, respectively. Among the patients treated by incomplete resection, the respective survival rates of those resected for metastases and of those resected for apical lymph node involvement did not differ significantly. We conclude that the involvement of apical lymph nodes has a significant effect on prognosis and suggest systematic pathologic examination of these nodes to allow simpler and more reproducible selection of patients for treatment by incomplete resection who are at high risk of disease-related death. PMID:8394236

  9. Hypertrophic cardiomyopathy with midventricular obstruction and apical aneurysm formation in a single family: case report

    Directory of Open Access Journals (Sweden)

    Paraskevaidis Stylianos

    2009-06-01

    Full Text Available Abstract Background Hypertrophic cardiomyopathy (HCM is an extremely heterogeneous disease. An under recognized and very often missed subgroup within this broad spectrum concerns patients with left ventricular (LV apical aneurysms in the absence of coronary artery disease. Case presentation We describe a case of HCM with midventricular obstruction and apical aneurysm formation in 3 patients coming from a single family. This HCM pattern was detected by 2D-echocardiography and confirmed by cardiac magnetic resonance imaging. A cardioverter defibrillator was implanted in one of the patients because of non-sustained ventricular tachycardia detected in 24-h Holter monitoring and an abrupt drop in systolic blood pressure during maximal exercise test. The defibrillator activated 8 months after implantation by suppression of a ventricular tachycardia providing anti-tachycardia pacing. The patient died due to refractory heart failure 2 years after initial evaluation. The rest of the patients are stable after a 2.5-y follow-up period. Conclusion The detection of apical aneurysm by echocardiography in HCM patients may be complicated. Ventricular tachycardia arising from the scarred aneurysm wall may often occur predisposing to sudden death.

  10. Integrins Regulate Apical Constriction via Microtubule Stabilization in the Drosophila Eye Disc Epithelium

    Directory of Open Access Journals (Sweden)

    Vilaiwan M. Fernandes

    2014-12-01

    Full Text Available During morphogenesis, extracellular signals trigger actomyosin contractility in subpopulations of cells to coordinate changes in cell shape. To illuminate the link between signaling-mediated tissue patterning and cytoskeletal remodeling, we study the progression of the morphogenetic furrow (MF, the wave of apical constriction that traverses the Drosophila eye imaginal disc preceding photoreceptor neurogenesis. Apical constriction depends on actomyosin contractility downstream of the Hedgehog (Hh and bone morphogenetic protein (BMP pathways. We identify a role for integrin adhesion receptors in MF progression. We show that Hh and BMP regulate integrin expression, the loss of which disrupts apical constriction and slows furrow progression; conversely, elevated integrins accelerate furrow progression. We present evidence that integrins regulate MF progression by promoting microtubule stabilization, since reducing microtubule stability rescues integrin-mediated furrow acceleration. Thus, integrins act as a genetic link between tissue-level signaling events and morphological change at the cellular level, leading to morphogenesis and neurogenesis in the eye.

  11. In vitro analysis of the apical deformation, using a different number of files during the instrumentation

    Directory of Open Access Journals (Sweden)

    Lucas da Fonseca Roberti GARCIA

    2009-12-01

    Full Text Available Introduction and objective: The aim of the present study was toevaluate in vitro the apical deformation in roots of crooked lowerincisors with mesio-distal flattening, using a different number of files during the instrumentation. Material and methods: Twenty rootswere randomly divided into two groups (n = 10. Group I: roots wereinitially instrumented with a K #15 file until a #35 file, through stepback technique. During instrumentation, the canals were irrigated with 1 mL of 1% NaOCl between every instrument change. Obturation wasperformed with Grossman sealer by lateral condensation technique.Group II: procedure was similar to group I, except for the files number, using file #40 as memory instrument. After that, each root was 1mm apical weared in order to reveal the filling. A 3 mm cut from the root apex was performed, resulting in samples with the same length, which were examined with an optical microscope (X40. The images captured by the Image Tool software were analyzed and the area occupied by sealer, gutta-percha and possible empty spaces was quantified. Results: Data was submitted to statistical analysis and showed no statistical significant differences between groups I and II (p > 0.05. Conclusion: The variation in the number of files during instrumentation did not promote apical deformation, but resulted in a similar hermetic sealing between the studied groups.

  12. Thalamic input to distal apical dendrites in neocortical layer 1 is massive and highly convergent.

    Science.gov (United States)

    Rubio-Garrido, Pablo; Pérez-de-Manzo, Flor; Porrero, César; Galazo, Maria J; Clascá, Francisco

    2009-10-01

    Input to apical dendritic tufts is now deemed crucial for associative learning, attention, and similar "feedback" interactions in the cerebral cortex. Excitatory input to apical tufts in neocortical layer 1 has been traditionally assumed to be predominantly cortical, as thalamic pathways directed to this layer were regarded relatively scant and diffuse. However, the sensitive tracing methods used in the present study show that, throughout the rat neocortex, large numbers (mean approximately 4500/mm(2)) of thalamocortical neurons converge in layer 1 and that this convergence gives rise to a very high local density of thalamic terminals. Moreover, we show that the layer 1-projecting neurons are present in large numbers in most, but not all, motor, association, limbic, and sensory nuclei of the rodent thalamus. Some layer 1-projecting axons branch to innervate large swaths of the cerebral hemisphere, whereas others arborize within only a single cortical area. Present data imply that realistic modeling of cortical circuitry should factor in a dense axonal canopy carrying highly convergent thalamocortical input to pyramidal cell apical tufts. In addition, they are consistent with the notion that layer 1-projecting axons may be a robust anatomical substrate for extensive "feedback" interactions between cortical areas via the thalamus.

  13. Supraventricular tachycardia in a patient with Lown-Ganong-Levine syndrome associated with apical hypertrophic cardiomyopathy.

    Science.gov (United States)

    Hayano, M; Imamura, Y; Tsuruta, M; Inoue, J; Nakashima, H; Fukuyama, K; Eguchi, Y; Tsuji, S; Matsuo, S; Yano, K

    1988-03-01

    Electrophysiologic study of a 55-year-old patient with Lown-Ganong-Levine syndrome associated with apical hypertrophic cardiomyopathy is reported. The patient had a history of recurrent attacks of tachyarrhythmia and his electrocardiogram showed a short P-R interval (0.10 sec) with narrow QRS complex and left ventricular hypertrophy with giant negative T waves. His cineangiogram showed severe apical hypertrophy. An electrophysiologic study was performed. The results of programmed atrial pacing show the existence of the dual A-V nodal pathways. The A-H interval at rapid atrial pacing increased maximally by 103 msec. Atrial stimulation could depolarize parts of the atrium without altering the supraventricular tachycardia. These findings suggested that preferential rapidly conducting A-V nodal and intranodal reentry are the responsible mechanisms in this reciprocating tachycardia. We conclude that the short P-R interval was due to intranodal reentry through the dual A-V nodal pathways. To our knowledge, a case of Lown-Ganong-Levine syndrome with apical hypertrophic cardiomyopathy has not been previously described in the literature.

  14. Influence of Instruments Used in Root Canal Preparation on Amount of Apically Extruded Debris.

    Science.gov (United States)

    Karataş, Ertuğrul; Ersoy, İbrahim; Gündüz, Hicran Ateş; Uygun, Ahmet Demirhan; Kol, Elif; Çakıcı, Fatih

    2016-08-01

    The aim of the present study was to compare the effects of ProTaper Gold, WaveOne Gold, ProTaper Universal, and WaveOne instruments on the amount of apically extruded debris. Eighty mandibular premolar teeth with straight root canals were selected and assigned to four groups (n = 20). The root canals were instrumented using ProTaper Gold, WaveOne Gold, ProTaper Universal, and WaveOne systems. Eppendorf tubes containing apically extruded debris were weighed three times, and mean values were calculated. The net mass of the extruded debris was calculated by subtracting the initial mass from the final mass. The groups were compared using one-way analysis of variance and Tukey's post hoc tests at a significance level of P < 0.05. The PTG group extruded less debris than the PTU group, and the WOG group extruded less debris than the WO group (P < 0.05). All the instrumentation systems tested in the present study were associated with apical extrusion of debris. PMID:26814380

  15. Takotsubo, discinesia apical transitoria: Presentacion de 4 casos y revisión de la literatura Takotsubo, reversible apical ballooning of the left ventricle: Report of 4 cases

    Directory of Open Access Journals (Sweden)

    Bárbara C. Finn

    2005-10-01

    Full Text Available En 1990 se describió un síndrome caracterizado por discinesia apical transitoria, cambios en el electrocardiograma (ECG, mínima elevación de enzimas cardíacas y arterias coronarias normales. Se presenta con mayor frecuencia en mujeres añosas y es precedido por un evento de estrés, ya sea físico o psíquico. La fisiopatología aún no está aclarada y se proponen diversas teorías. La de mayor peso es la que postula una afección secundaria a la descarga de catecolaminas desencadenada por el estrés, sobre un corazón incapaz de mantener una respuesta inotrópica adecuada. Se presentan cuatro casos de pacientes atendidos en nuestro hospital que se manifestaron con síntomas sugerentes de infarto agudo de miocardio asociados a insuficiencia cardiaca, en el contexto de un episodio estresante. Los síntomas preponderantes fueron dolor precordial opresivo y disnea. En el ECG se evidenciaron tanto supradesnivel del segmento ST, como inversión de la onda T. Todos los pacientes presentaron la imagen ecocardiográfica típica de discinesia apical, y todos tuvieron en la cinecoronariografía coronarias normales. Cabe destacar que tanto el ECG, como el ecocardiograma volvieron a la normalidad a partir de las dos semanas.A syndrome of apical ballooning, with ECG mimicking acute myocardial infarctation, mild or no enzymatic changes, and normal coronary angiogram was described in 1990. It presents mainly in middle aged and elderly women and it is preceded by stress triggering circumstances. Several mechanisms have been proposed although the precise cause remains unclear. The most accepted theory proposes the interaction of catecholamines and an inadequate inotropic response. We report four cases that presented with chest pain and sudden onset of heart failure, all patients had physical or emotional stress as a triggering factor. On ECG, ST segment elevation and inverted T waves were observed in the acute phase. All patients had typical echocardiogram

  16. Control of sigma virus multiplication by the ref(2)P gene of Drosophila melanogaster: an in vivo study of the PB1 domain of Ref(2)P.

    Science.gov (United States)

    Carré-Mlouka, A; Gaumer, S; Gay, P; Petitjean, A M; Coulondre, C; Dru, P; Bras, F; Dezélée, S; Contamine, D

    2007-05-01

    Ref(2)P has been described as one of the Drosophila proteins that interacts with the sigma virus cycle. We generated alleles to identify critical residues involved in the restrictive (inhibiting viral multiplication) or permissive (allowing viral multiplication) character of Ref(2)P. We demonstrate that permissive alleles increase the ability of the sigma virus to infect Drosophila when compared to null alleles and we confirm that restrictive alleles decrease this capacity. Moreover, we have created alleles unfunctional in viral cycling while functional for Ref(2)P fly functions. This type of allele had never been observed before and shows that fly- and virus-related activities of Ref(2)P are separable. The viral status of Ref(2)P variants is determined by the amino-terminal PB1 domain polymorphism. In addition, an isolated PB1 domain mimics virus-related functions even if it is similar to a loss of function toward fly-related activities. The evolutionary tree of the Ref(2)P PB1 domain that we could build on the basis of the natural allele sequences is in agreement with an evolution of PB1 domain due to successive transient selection waves.

  17. A short Gfi-1B isoform controls erythroid differentiation by recruiting the LSD1-corest complex through the dimethylation of its SNAG domain

    NARCIS (Netherlands)

    B. Laurent (Benoît); V. Randrianarison-Huetz (Voahangy); E. Frisan (Emilie); C. Andrieu-Soler (Charlotte); E. Soler (Eric); M. Fontenay (Michaela); I. Dusanter-Fourt (Isabelle); D. Dumenil (Dominique)

    2012-01-01

    textabstractGfi-1B is a transcriptional repressor essential for the regulation of erythropoiesis and megakaryopoiesis. Here we identify Gfi-1B p32, a Gfi-1B isoform, as essential for erythroid differentiation. Gfi-1B p32 is generated by alternative splicing and lacks the two first zinc finger domain

  18. Protein domain prediction

    NARCIS (Netherlands)

    Ingolfsson, Helgi; Yona, Golan

    2008-01-01

    Domains are considered to be the building blocks of protein structures. A protein can contain a single domain or multiple domains, each one typically associated with a specific function. The combination of domains determines the function of the protein, its subcellular localization and the interacti

  19. XBAT35, a Novel Arabidopsis RING E3 Ligase Exhibiting Dual Targeting of Its Splice Isoforms,Is Involved in Ethylene-Mediated Regulation of Apical Hook Curvature

    Institute of Scientific and Technical Information of China (English)

    Sofia D.Carvalho; Rita Saraiva; Teresa M.Maia; Isabel A.Abreu; Paula Duque

    2012-01-01

    The Arabidopsis XBAT35 is one of five structurally related ankyrin repeat-containing Really interesting New Gene (RING) E3 ligases involved in ubiquitin-mediated protein degradation,which plays key roles in a wide range of cellular processes.Here,we show that the XBAT35 gene undergoes alternative splicing,generating two transcripts that are constitutively expressed in all plant tissues.The two splice variants derive from an exon skipping event that excludes an in-frame segment from the XBAT35 precursor mRNA,giving rise to two protein isoforms that differ solely in the presence of a nuclear localization signal (NLS).Transient expression assays indicate that the isoform lacking the NLS localizes in the cytoplasm of plant cells,whereas the other is targeted to the nucleus,accumulating in nuclear speckles.Both isoforms are functional E3 ligases,as assessed by in vitro ubiquitination assays.Two insertion mutant alleles and RNA-interference (RNAi) silencing lines for XBAT35 display no evident phenotypes under normal growth conditions,but exhibit hypersensitivity to the ethylene precursor 1-aminocyclopropane-1-carboxylate (ACC) during apical hook exaggeration in the dark,which is rescued by an inhibitor of ethylene perception.Independent expression of each XBAT35 splice variant in the mutant background indicates that the two isoforms may differentially contribute to apical hook formation but are both functional in this ethylene-mediated response.Thus,XBAT35 defines a novel player in ethylene signaling involved in negatively regulating apical hook curvature,with alternative splicing controlling dual targeting of this E3 ubiquitin ligase to the nuclear and cytoplasmic compartments.

  20. Drosophila Stardust is a partner of Crumbs in the control of epithelial cell polarity.

    Science.gov (United States)

    Bachmann, A; Schneider, M; Theilenberg, E; Grawe, F; Knust, E

    2001-12-01

    The polarized architecture of epithelial cells depends on the highly stereotypic distribution of cellular junctions and other membrane-associated protein complexes. In epithelial cells of the Drosophila embryo, three distinct domains subdivide the lateral plasma membrane. The most apical one comprises the subapical complex (SAC). It is followed by the zonula adherens (ZA) and, further basally, by the septate junction. A core component of the SAC is the transmembrane protein Crumbs, the cytoplasmic domain of which recruits the PDZ-protein Discs Lost into the complex. Cells lacking crumbs or the functionally related gene stardust fail to organize a continuous ZA and to maintain cell polarity. Here we show that stardust provides an essential component of the SAC. Stardust proteins colocalize with Crumbs and bind to the carboxy-terminal amino acids of its cytoplasmic tail. We introduce two different Stardust proteins here: one MAGUK protein, characterized by a PDZ domain, an SH3 domain and a guanylate kinase domain; and a second isoform comprising only the guanylate kinase domain. The Stardust proteins represent versatile candidates as structural and possibly regulatory constituents of the SAC, a crucial element in the control of epithelial cell polarity.

  1. [Deformations occurring in the apical third of curved root canals during biomechanical preparation using manual impulsion-traction techniques].

    Science.gov (United States)

    Roig Cayón, M; Basilio Monné, J; Canalda Sahli, C

    1990-01-01

    Apical deformations, specially zips and elbows, during instrumentation of the root canals, are studied. The authors study why do they appear, their effect on endodontic therapy, and the way of avoiding them. PMID:1964069

  2. [Deformations occurring in the apical third of curved root canals during biomechanical preparation using manual impulsion-traction techniques].

    Science.gov (United States)

    Roig Cayón, M; Basilio Monné, J; Canalda Sahli, C

    1990-01-01

    Apical deformations, specially zips and elbows, during instrumentation of the root canals, are studied. The authors study why do they appear, their effect on endodontic therapy, and the way of avoiding them.

  3. Epstein-Barr virus infection induces bone resorption in apical periodontitis via increased production of reactive oxygen species.

    Science.gov (United States)

    Jakovljevic, Aleksandar; Andric, Miroslav; Miletic, Maja; Beljic-Ivanovic, Katarina; Knezevic, Aleksandra; Mojsilovic, Slavko; Milasin, Jelena

    2016-09-01

    Chronic inflammatory processes in periapical tissues caused by etiological agents of endodontic origin lead to apical periodontitis. Apart from bacteria, two herpesviruses, Epstein-Barr virus (EBV) and Human cytomegalovirus (HCMV) are recognized as putative pathogens in apical periodontitis. Although previous reports suggest the involvement of EBV in the pathogenesis of apical periodontitis, its exact role in periapical bone resorption has not yet been fully elucidated. We hypothesize that EBV infection in apical periodontitis is capable of inducing periapical bone resorption via stimulation of reactive oxygen species (ROS) overproduction. Increased levels of ROS induce expression of receptor activator of nuclear factor kappa B (NF-κB) ligand (RANKL). RANKL binding to receptor activator of nuclear factor κB (RANK) present on the surface of preosteoclasts induces their maturation and activation which consequently leads to bone resorption. The potential benefit of antiviral and antioxidant-based therapies in periapical bone resorption treatment remains to be assessed. PMID:27515196

  4. Microbial sphingomyelinase induces RhoA-mediated reorganization of the apical brush border membrane and is protective against invasion.

    Science.gov (United States)

    Saslowsky, David E; Thiagarajah, Jay R; McCormick, Beth A; Lee, Jean C; Lencer, Wayne I

    2016-04-01

    The apical brush border membrane (BBM) of intestinal epithelial cells forms a highly structured and dynamic environmental interface that serves to regulate cellular physiology and block invasion by intestinal microbes and their products. How the BBM dynamically responds to pathogenic and commensal bacterial signals can define intestinal homeostasis and immune function. We previously found that in model intestinal epithelium, the conversion of apical membrane sphingomyelin to ceramide by exogenous bacterial sphingomyelinase (SMase) protected against the endocytosis and toxicity of cholera toxin. Here we elucidate a mechanism of action by showing that SMase induces a dramatic, reversible, RhoA-dependent alteration of the apical cortical F-actin network. Accumulation of apical membrane ceramide is necessary and sufficient to induce the actin phenotype, and this coincides with altered membrane structure and augmented innate immune function as evidenced by resistance to invasion by Salmonella. PMID:26864627

  5. The effect of bevel angle on apical microleakage following the use of amalgam and MTA

    Directory of Open Access Journals (Sweden)

    Sharifian MR

    2006-07-01

    Full Text Available Background and Aim: Achieving appropriate seal in canal obturation is the main goal of endodontic therapy. However, in some cases, it can not be obtained by non-surgical procedures alone. Retrograde surgery is one of the most common procedures in endodontics. Apical seal improvement can be obtained by root end filling and decreasing the root end resection angle (bevel angle. The aim of this study was to investigate the role of bevel angle on apical microleakage following the use of amalgam and MTA as root end filling materials. Materials and Methods: In this experimental study, 128 extracted human teeth were instrumented and obturated by lateral condensation technique. The teeth were divided into two groups and the apical root resection was performed by high speed fissure bur (one group perpendicular to the long axis of the teeth and the other 45 to the long axis. The 3 mm root end cavity was prepared by ultrasonic device. Each group was divided into two subgroups: One filled with amalgam and the other with MTA. Teeth were incubated for 72 h, covered by two layers of nail polish (except for apical 3mm and submerged in methylene blue for 48 h. Teeth were washed under tap water and mesiodistally dissected by low speed disc. Dye penetration was evaluated by stereomicroscope. Data were analysed by two way ANOVA and Tukey tests with p<0.05 as the limit of significance. Results: The results showed that retrofill material type had a significant effect on microleakage and MTA was superior to amalgam in this respect. Bevel angle failed to show any significant effect on apical microleakage. Conclusion: Based on the results of this study, it seems that the use of MTA instead of amalgam in clinical practice can improve the success rate of endodontic surgery whereas the bevel angle can be determined based on the status of each individual case; However, increasing the bevel angle seems to increase microleakage due to exposure of more dentinal tubules.

  6. Depletion of histone demethylase KDM2A enhanced the adipogenic and chondrogenic differentiation potentials of stem cells from apical papilla

    International Nuclear Information System (INIS)

    Mesenchymal stem cells (MSCs) are a reliable resource for tissue regeneration, but the molecular mechanism underlying directed differentiation remains unclear; this has restricted potential MSC applications. The histone demethylase, lysine (K)-specific demethylase 2A (KDM2A), is evolutionarily conserved and ubiquitously expressed members of the JmjC-domain-containing histone demethylase family. A previous study determined that KDM2A can regulate the cell proliferation and osteo/dentinogenic differentiation of MSCs. It is not known whether KDM2A is involved in the other cell lineages differentiation of MSCs. Here, we show that depletion of KDM2A by short hairpin RNAs can enhance adipogenic and chondrogenic differentiation potentials in human stem cells from apical papilla (SCAPs). We found that the stemness-related genes, SOX2, and the embryonic stem cell master transcription factor, NANOG were significantly increased after silence of KDM2A in SCAPs. Moreover, we found that knock-down of the KDM2A co-factor, BCOR also up-regulated the mRNA levels of SOX2 and NANOG. Furthermore, Chromatin immunoprecipitation assays demonstrate that silence of KDM2A increased the histone H3 Lysine 4 (H3K4) trimethylation in the SOX2 and NANOG locus and regulates its expression. In conclusion, our results suggested that depletion of KDM2A enhanced the adipogenic and chondrogenic differentiation potentials of SCAPs by up-regulated SOX2 and NANOG, BCOR also involved in this regulation as co-factor, and provided useful information to understand the molecular mechanism underlying directed differentiation in MSCs. - Highlights: • Depletion of KDM2A enhances adipogenic/chondrogenic differentiation in SCAPs. • Depletion of KDM2A enhances the differentiation of SCAPs by activate SOX2 and NANOG. • Silence of KDM2A increases histone H3 Lysine 4 trimethylation in SOX2 and NANOG. • BCOR is co-factor of KDM2A involved in the differentiation regulation

  7. Depletion of histone demethylase KDM2A enhanced the adipogenic and chondrogenic differentiation potentials of stem cells from apical papilla

    Energy Technology Data Exchange (ETDEWEB)

    Dong, Rui [Laboratory of Molecular Signaling and Stem Cells Therapy, Beijing Key Laboratory of Tooth Regeneration and Function Reconstruction, Capital Medical University School of Stomatology, Beijing 100050 (China); Yao, Rui [Department of Pediatrics, Stomatological Hospital of Nankai University, Tianjin 300041 (China); Du, Juan [Laboratory of Molecular Signaling and Stem Cells Therapy, Beijing Key Laboratory of Tooth Regeneration and Function Reconstruction, Capital Medical University School of Stomatology, Beijing 100050 (China); Wang, Songlin [Molecular Laboratory for Gene Therapy and Tooth Regeneration, Beijing Key Laboratory of Tooth Regeneration and Function Reconstruction, Capital Medical University School of Stomatology, Beijing 100050 (China); Department of Biochemistry and Molecular Biology, Capital Medical University School of Basic Medical Sciences, Beijing 100069 (China); Fan, Zhipeng, E-mail: zpfan@ccmu.edu.cn [Laboratory of Molecular Signaling and Stem Cells Therapy, Beijing Key Laboratory of Tooth Regeneration and Function Reconstruction, Capital Medical University School of Stomatology, Beijing 100050 (China)

    2013-11-01

    Mesenchymal stem cells (MSCs) are a reliable resource for tissue regeneration, but the molecular mechanism underlying directed differentiation remains unclear; this has restricted potential MSC applications. The histone demethylase, lysine (K)-specific demethylase 2A (KDM2A), is evolutionarily conserved and ubiquitously expressed members of the JmjC-domain-containing histone demethylase family. A previous study determined that KDM2A can regulate the cell proliferation and osteo/dentinogenic differentiation of MSCs. It is not known whether KDM2A is involved in the other cell lineages differentiation of MSCs. Here, we show that depletion of KDM2A by short hairpin RNAs can enhance adipogenic and chondrogenic differentiation potentials in human stem cells from apical papilla (SCAPs). We found that the stemness-related genes, SOX2, and the embryonic stem cell master transcription factor, NANOG were significantly increased after silence of KDM2A in SCAPs. Moreover, we found that knock-down of the KDM2A co-factor, BCOR also up-regulated the mRNA levels of SOX2 and NANOG. Furthermore, Chromatin immunoprecipitation assays demonstrate that silence of KDM2A increased the histone H3 Lysine 4 (H3K4) trimethylation in the SOX2 and NANOG locus and regulates its expression. In conclusion, our results suggested that depletion of KDM2A enhanced the adipogenic and chondrogenic differentiation potentials of SCAPs by up-regulated SOX2 and NANOG, BCOR also involved in this regulation as co-factor, and provided useful information to understand the molecular mechanism underlying directed differentiation in MSCs. - Highlights: • Depletion of KDM2A enhances adipogenic/chondrogenic differentiation in SCAPs. • Depletion of KDM2A enhances the differentiation of SCAPs by activate SOX2 and NANOG. • Silence of KDM2A increases histone H3 Lysine 4 trimethylation in SOX2 and NANOG. • BCOR is co-factor of KDM2A involved in the differentiation regulation.

  8. Auxin apical control of the auxin polar transport and its oscillation - a suggested cellular transduction mechanism

    Directory of Open Access Journals (Sweden)

    Tomasz J. Wodzicki

    2014-02-01

    Full Text Available The proposed hypothesis concerns the transduction of auxin molecular signals arriving from the apoplast at the plasma membrane or recognized by the proteineous receptors of the responding cell, to the concentration gradients oscillating in the supracellular space, associated usually with the specific plant growth and differentiation. Acting as an agonist from outside the target cell auxin stimulates in this cell: (1 the liberation of auxin from the cytosolic pool of its conjugates directly into the basipetal efflux; (2 the synthesis of new auxin which restores the cytosolic reserve of auxin conjugates. The functioning of such a system may be effective in a series of processes initiated by the changing concentration of cytosolic calcium. The hypothesis suggests a molecular mechanism for the development and effective operation of the morphogenetic field in the supracellular space of the plant body, such as the field resulting from auxin waves discovered in cambium.

  9. Apical ballooning syndrome complicated by acute severe mitral regurgitation with left ventricular outflow obstruction – Case report

    OpenAIRE

    Celermajer David S; Chandrasegaram Manju D; Wilson Michael K

    2007-01-01

    Abstract Background Apical ballooning syndrome (or Takotsubo cardiomyopathy) is a syndrome of transient left ventricular apical ballooning. Although first described in Japanese patients, it is now well reported in the Caucasian population. The syndrome mimicks an acute myocardial infarction but is characterised by the absence of obstructive coronary disease. We describe a serious and poorly understood complication of Takotsubo cardiomyopathy. Case Presentation We present the case of a 65 year...

  10. Potassium transport across rat alveolar epithelium: evidence for an apical Na+-K+ pump.

    Science.gov (United States)

    Basset, G; Bouchonnet, F; Crone, C; Saumon, G

    1988-06-01

    1. Experiments were performed on rat lungs into which various solutions were instilled whilst the lungs were perfused with either whole blood or Ringer solution. Instillation of ion-free glucose solution led to a net flux of fluid and ions into the alveolar spaces. K+ ions entered faster than Na+ ions and reached a concentration about twice that in the perfusate. Ouabain in the perfusate (basolateral side) prevented the rise in alveolar K+ concentration above that in the perfusate, indicating a transcellular pathway. Ba2+ in the instillate (apical side) hindered the entry of K+ into alveoli, suggesting the presence of apical K+ channels. 2. When Ringer solution was instilled, K+ was continuously removed from the alveoli and the K+ concentration in the instillate remained constant or decreased slightly depending on the rate of fluid absorption. The net K+ efflux from alveoli to blood was 0.23 pmol/(cm2 s). When Ba2+ was added to the instillate the net K+ efflux increased to 0.36 pmol/(cm2 s). Apical ouabain reversed the K+ flux resulting in a net K+ flux of 0.19 pmol/(cm2 s) into the alveoli. This suggests the presence of an Na+-K+-ATPase located in the apical membrane of some alveolar cells. 3. The K+ transport from instillate (Ringer solution) to perfusate was traced by means of 86Rb which was added to the instillate. Ouabain in the instillate did not affect fluid absorption but reduced the apparent 86Rb permeability by 50% although the paracellular permeability (estimated with [3H]mannitol) was unaffected. This also indicates the presence of an apical Na+-K+-ATPase. When ouabain was added to the perfusate, the apparent 86Rb permeability doubled. These findings indicate that recirculation of 86Rb (and K+) occurs due to the activity of both apical and basolateral Na+-K+-ATPases. 4. When ouabain was placed on both sides of the epithelium, preventing transcellular transport, the passive 86Rb permeability was 10.3 x 10(-8) cm/s (assuming an alveolar surface area of

  11. Mineral trioxide aggregate apical plug method for the treatment of nonvital immature permanent maxillary incisors: Three case reports

    Directory of Open Access Journals (Sweden)

    Betül Günes

    2012-01-01

    Full Text Available Treatment of nonvital immature permanent teeth with calcium-hydroxide is associated with some difficulties such as weakened tooth fracture, root canal reinfection and long treatment time. Mineral trioxide aggregate (MTA apical plug method is an alternative treatment option for open apices, and has gained popularity in the recent times. In this case report, we have attempted to present successful treatment of three maxillary incisors with open apices and periapical lesions with MTA. After preparing the access cavity, the working length was determined. The root canals were irrigated with 2.5% Sodium hypochlorite (NaOCl and disinfected with calcium-hydroxide for two weeks. MTA was then placed in the apical 3 millimeters of the root canal. The remaining part of the root canal was filled with gutta-percha and the coronal restoration was finished with composite resin. After six months the radiographic examination showed a decrease of periapical lesions. At a 1-year and 18-months follow up, radiological and clinical successful healing of the incisor teeth was seen. MTA seems as an effective material for the apical plug method for the treatment of nonvital immature permanent teeth with open apices.

  12. Fractal dimension of apical dendritic arborization differs in the superficial and the deep pyramidal neurons of the rat cerebral neocortex.

    Science.gov (United States)

    Puškaš, Nela; Zaletel, Ivan; Stefanović, Bratislav D; Ristanović, Dušan

    2015-03-01

    Pyramidal neurons of the mammalian cerebral cortex have specific structure and pattern of organization that involves the presence of apical dendrite. Morphology of the apical dendrite is well-known, but quantification of its complexity still remains open. Fractal analysis has proved to be a valuable method for analyzing the complexity of dendrite morphology. The aim of this study was to establish the fractal dimension of apical dendrite arborization of pyramidal neurons in distinct neocortical laminae by using the modified box-counting method. A total of thirty, Golgi impregnated neurons from the rat brain were analyzed: 15 superficial (cell bodies located within lamina II-III), and 15 deep pyramidal neurons (cell bodies situated within lamina V-VI). Analysis of topological parameters of apical dendrite arborization showed no statistical differences except in total dendritic length (p=0.02), indicating considerable homogeneity between the two groups of neurons. On the other hand, average fractal dimension of apical dendrite was 1.33±0.06 for the superficial and 1.24±0.04 for the deep cortical neurons, showing statistically significant difference between these two groups (pfractal dimension values, apical dendrites of the superficial pyramidal neurons tend to show higher structural complexity compared to the deep ones.

  13. Sudden Cardiac Arrest in a Patient With Apical Hypertrophic Cardiomyopathy: Case Report and a Brief Review of Literature.

    Science.gov (United States)

    Gupta, Tanush; Paul, Neha; Palaniswamy, Chandrasekar; Balasubramaniyam, Nivas; Aronow, Wilbert S; Kolte, Dhaval; Khera, Sahil; Shah, Amar B; Gass, Alan

    2016-01-01

    Apical hypertrophic cardiomyopathy (HCM) is a phenotypic variant of nonobstructive HCM, in which hypertrophy of the myocardium predominantly involves the left ventricular apex. It is common in Japanese and other Asian populations but is rare in the United States. Apical HCM has a relatively benign prognosis in terms of cardiovascular mortality; however, morbid events such as ventricular aneurysms, apical thrombi, diastolic dysfunction, atrial fibrillation, and myocardial infarction are not uncommon. We report a case of an 18-year-old white man who presented to our hospital after an out-of-hospital cardiac arrest. The patient had a witnessed collapse while playing basketball in the field. He was found to be pulseless and unresponsive by his coach, and cardiopulmonary resuscitation was immediately started. Upon arrival of emergency medical services, an automated external defibrillator advised shock and he was defibrillated thrice. Return of spontaneous circulation was achieved in 15 minutes. He was intubated for airway protection and was brought to the hospital. Therapeutic hypothermia was initiated. He demonstrated good neurological status after active rewarming. Subsequent cardiac magnetic resonance imaging was suggestive of apical HCM with right ventricular involvement. The patient underwent an implantable cardioverter defibrillator placement for secondary prevention and was subsequently discharged. In conclusion, apical HCM can rarely be associated with adverse cardiovascular events. The diagnosis may be missed on transthoracic 2-dimensional cardiac echocardiogram, and cardiac magnetic resonance imaging should be considered to exclude apical HCM in young patients who present after sudden cardiac arrest. PMID:25923227

  14. Geometric control of ciliated band regulatory states in the sea urchin embryo.

    Science.gov (United States)

    Barsi, Julius C; Li, Enhu; Davidson, Eric H

    2015-03-01

    The trapezoidal ciliated band (CB) of the postgastrular sea urchin embryo surrounds the oral ectoderm, separating it from adjacent embryonic territories. Once differentiated, the CB is composed of densely arranged cells bearing long cilia that endow the larva with locomotion and feeding capability. The spatial pattern from which the CB will arise is first evidenced during pregastrular stages by expression of the pioneer gene onecut. Immediately after gastrulation, the CB consists of four separate regulatory state domains, each of which expresses a unique set of transcription factors: (1) the oral apical CB, located within the apical neurogenic field; (2) the animal lateral CB, which bilaterally separates the oral from aboral ectoderm; (3) the vegetal lateral CB, which bilaterally serves as signaling centers; and (4) the vegetal oral CB, which delineates the boundary with the underlying endoderm. Remarkably, almost all of the regulatory genes specifically expressed within these domains are downregulated by interference with SoxB1 expression, implying their common activation by this factor. Here, we show how the boundaries of the CB subdomains are established, and thus ascertain the design principle by which the geometry of this unique and complex regulatory state pattern is genomically controlled. Each of these boundaries, on either side of the CB, is defined by spatially confined transcriptional repressors, the products of regulatory genes operating across the border of each subdomain. In total this requires deployment of about ten different repressors, which we identify in this work, thus exemplifying the complexity of information required for spatial regulatory organization during embryogenesis.

  15. AMP-activated protein kinase inhibits alkaline pH- and PKA-induced apical vacuolar H+-ATPase accumulation in epididymal clear cells.

    Science.gov (United States)

    Hallows, Kenneth R; Alzamora, Rodrigo; Li, Hui; Gong, Fan; Smolak, Christy; Neumann, Dietbert; Pastor-Soler, Núria M

    2009-04-01

    Acidic luminal pH and low [HCO(3)(-)] maintain sperm quiescent during maturation in the epididymis. The vacuolar H(+)-ATPase (V-ATPase) in clear cells is a major contributor to epididymal luminal acidification. We have shown previously that protein kinase A (PKA), acting downstream of soluble adenylyl cyclase stimulation by alkaline luminal pH or HCO(3)(-), induces V-ATPase apical membrane accumulation in clear cells. Here we examined whether the metabolic sensor AMP-activated protein kinase (AMPK) regulates this PKA-induced V-ATPase apical membrane accumulation. Immunofluorescence labeling of rat and non-human primate epididymides revealed specific AMPK expression in epithelial cells. Immunofluorescence labeling of rat epididymis showed that perfusion in vivo with the AMPK activators 5-aminoimidazole-4-carboxamide-1-beta-d-ribofuranoside (AICAR) or A-769662 induced a redistribution of the V-ATPase into subapical vesicles, even in the presence of a luminal alkaline (pH 7.8) buffer compared with that of controls perfused without drug. Moreover, preperfusion with AICAR blocked the PKA-mediated V-ATPase translocation to clear cell apical membranes induced by N(6)-monobutyryl-cAMP (6-MB-cAMP). Purified PKA and AMPK both phosphorylated V-ATPase A subunit in vitro. In HEK-293 cells [(32)P]orthophosphate in vivo labeling of the A subunit increased following PKA stimulation and decreased following RNA interference-mediated knockdown of AMPK. Finally, the extent of PKA-dependent in vivo phosphorylation of the A subunit increased with AMPK knockdown. In summary, our findings suggest that AMPK inhibits PKA-mediated V-ATPase apical accumulation in epididymal clear cells, that both kinases directly phosphorylate the V-ATPase A subunit in vitro and in vivo, and that AMPK inhibits PKA-dependent phosphorylation of this subunit. V-ATPase activity may be coupled to the sensing of acid-base status via PKA and to metabolic status via AMPK. PMID:19211918

  16. Receiver domains control the active state stoichiometry of Aquifex aeolicus σ54 activator NtrC4, as revealed by electrospray mass spectrometry

    OpenAIRE

    Batchelor, Joseph D.; Sterling, Harry J; Hong, Eunmi; Williams, Evan R.; Wemmer, David E.

    2009-01-01

    A common challenge with studies of proteins in vitro is determining which constructs and conditions are most physiologically relevant. σ54 activators are proteins that undergo regulated assembly to form an active ATPase ring that enables transcription by σ54-polymerase. Previous studies of the AAA+ ATPase domains from σ54 activators have shown that some are heptamers, while others are hexamers. Because the active oligomers assemble from off-state dimers, it was thought that even-numbered olig...

  17. Apo-states of calmodulin and CaBP1 control CaV1 voltage-gated calcium channel function through direct competition for the IQ domain

    Science.gov (United States)

    Findeisen, Felix; Rumpf, Christine; Minor, Daniel L.

    2013-01-01

    In neurons, binding of calmodulin (CaM) or calcium-binding protein 1 (CaBP1) to the CaV1 (L-type) voltage-gated calcium channel IQ domain endows the channel with diametrically opposed properties. CaM causes calcium-dependent inactivation (CDI) and limits calcium entry, whereas CaBP1 blocks CDI and allows sustained calcium influx. Here, we combine isothermal titration calorimetry (ITC) with cell-based functional measurements and mathematical modeling to show that these calcium sensors behave in a competitive manner that is explained quantitatively by their apo-state binding affinities for the IQ domain. This competition can be completely blocked by covalent tethering of CaM to the channel. Further, we show that Ca2+/CaM has a sub-picomolar affinity for the IQ domain that is achieved without drastic alteration of calcium binding properties. The observation that the apo-forms of CaM and CaBP1 compete with each other demonstrates a simple mechanism for direct modulation of CaV1 function and suggests a means by which excitable cells may dynamically tune CaV activity. PMID:23811053

  18. 面向多级多域信息系统的访问控制方法研究%Research of access control method on multi-level & multi-domain information system

    Institute of Scientific and Technical Information of China (English)

    熊雄; 王福喜; 左海洋

    2011-01-01

    To solve the access control problem about multi-level & multi-domain information system, a method based on security level access control model is proposed after analyzing complex information system. The experimental result has proved that the access control model has achieved the predetermined goal that it can set the security level according to kinds of factors of multi-level & multi-domain information system and then control the access by the comparison of security level. And it is easier to deploy on multi-level & multi-domain information system, reacts more rapidly for change of authority, and limits the flow of unsafe information for access control model based on security level comparing with other ordinary ones.%针对常用的访问控制模型不能很好地解决多级多域信息系统的访问控制问题,分析了多级多域信息系统的结构特征,提出并实现了一种基于安全级别的访问控制模型.实验结果表明,该访问控制模型达到了预定的目标,可以针对多级多域信息系统的各要素分别进行安全级别设定,通过对安全级别的比较进行访问控制.基于安全级别的访问控制模型相对常用的访问控制模型,具有在多级多域信息系统上更容易部署、对权限的变更反应更为迅速,并且能够限制不安全的信息流动等特点.

  19. Transcriptome profiling of low temperature-treated cassava apical shoots showed dynamic responses of tropical plant to cold stress

    Directory of Open Access Journals (Sweden)

    An Dong

    2012-02-01

    Full Text Available Abstract Background Cassava is an important tropical root crop adapted to a wide range of environmental stimuli such as drought and acid soils. Nevertheless, it is an extremely cold-sensitive tropical species. Thus far, there is limited information about gene regulation and signalling pathways related to the cold stress response in cassava. The development of microarray technology has accelerated the study of global transcription profiling under certain conditions. Results A 60-mer oligonucleotide microarray representing 20,840 genes was used to perform transcriptome profiling in apical shoots of cassava subjected to cold at 7°C for 0, 4 and 9 h. A total of 508 transcripts were identified as early cold-responsive genes in which 319 sequences had functional descriptions when aligned with Arabidopsis proteins. Gene ontology annotation analysis identified many cold-relevant categories, including 'Response to abiotic and biotic stimulus', 'Response to stress', 'Transcription factor activity', and 'Chloroplast'. Various stress-associated genes with a wide range of biological functions were found, such as signal transduction components (e.g., MAP kinase 4, transcription factors (TFs, e.g., RAP2.11, and reactive oxygen species (ROS scavenging enzymes (e.g., catalase 2, as well as photosynthesis-related genes (e.g., PsaL. Seventeen major TF families including many well-studied members (e.g., AP2-EREBP were also involved in the early response to cold stress. Meanwhile, KEGG pathway analysis uncovered many important pathways, such as 'Plant hormone signal transduction' and 'Starch and sucrose metabolism'. Furthermore, the expression changes of 32 genes under cold and other abiotic stress conditions were validated by real-time RT-PCR. Importantly, most of the tested stress-responsive genes were primarily expressed in mature leaves, stem cambia, and fibrous roots rather than apical buds and young leaves. As a response to cold stress in cassava, an increase

  20. Initiation of mammalian O-mannosylation in vivo is independent of a consensus sequence and controlled by peptide regions within and upstream of the alpha-dystroglycan mucin domain.

    Science.gov (United States)

    Breloy, Isabelle; Schwientek, Tilo; Gries, Barbara; Razawi, Hanieh; Macht, Marcus; Albers, Christian; Hanisch, Franz-Georg

    2008-07-01

    To reveal insight into the initiation of mammalian O-mannosylation in vivo, recombinant glycosylation probes containing sections of human alpha-dystroglycan (hDG) were expressed in epithelial cell lines. We demonstrate that O-mannosylation within the mucin domain of hDG occurs preferentially at Thr/Ser residues that are flanked by basic amino acids. Protein O-mannosylation is independent of a consensus sequence, but strictly dependent on a peptide region located upstream of the mucin domain. This peptide region cannot be replaced by other N-terminal peptides, however, it is not sufficient to induce O-mannosylation on a structurally distinct mucin domain in hybrid constructs. The presented in vivo evidence for a more complex regulation of mammalian O-mannosylation contrasts with a recent in vitro study of O-mannosylation in human alpha-dystroglycan peptides indicating the existence of an 18-meric consensus sequence. We demonstrate in vivo that the entire region p377-417 is necessary and sufficient for O-mannosylation initiation of hDG, but not of MUC1 tandem repeats. The feature of a doubly controlled initiation process distinguishes mammalian O-mannosylation from other types of O-glycosylation, which are largely controlled by structural properties of the substrate positions and their local peptide environment.

  1. The effect of an Nd-YAG pulsed laser on the cleaning of the root canal and the formation of a fused apical plug.

    Science.gov (United States)

    Saunders, W P; Whitters, C J; Strang, R; Moseley, H; Payne, A P; McGadey, J

    1995-07-01

    A Neodymium-yttrium aluminium garnet (Nd-YAG) pulsed laser was used in vitro to determine whether various laser energy levels from 0.75 W to 1.7 W at 15 pulses s(-1) (pps) were able to (i) remove debris from the walls of prepared root canals (ii) remove pulpal tissue from unprepared canals and (iii) create a fused apical plug from dentine chips, hydroxyapatite (HAP) or low-fusing dental porcelain. Single-rooted teeth were sectioned at the amelocemental junction and the crowns discarded. The root canals of 50 teeth were prepared chemomechanically and allocated to four groups of 10 teeth for laser treatment. One group was left unlased as a control. After lasing, the teeth were split longitudinally, stained and examined for residual debris. Results showed that there was no statistically significant difference between the groups (Plaser energy was applied to dentine chips, HAP and low-fusing porcelain in an attempt to produce a fused apical plug. The laser was unable to melt the dentine chips but some hardening of HAP occurred when combined with blue food-colouring, with or without glycerine, at energy levels of 1.0 W, at 15 pps for 30 s. Superficial hardening of low-fusing porcelain occurred at 1.0 W, 15 pps for 30 s.

  2. An In Vitro Comparison ofApical Leakage of Biocalex, White MTA, Gray MTA, and Amalgam as Root-End Fillings

    Directory of Open Access Journals (Sweden)

    P. Ghaziani

    2008-09-01

    Full Text Available Objective: In a cavity prepared through endodontic surgery, application of a material to provide apical seal and prevent bacterial and tissue exudates is of great importance. The purpose of this study was to compare the sealing ability of Biocalex with white MTA, gray MTA, and amalgam as root-end fillings.Materials and Methods: Sixty-six single-rooted extracted human teeth were cleaned, shaped, and obturated with gutta-percha. The root apices were resected and 3 mm deep retrograde cavity was prepared. The teeth were assigned randomly into four groups of 15 teeth each and retrofilled with Biocalex, gray MTA, white MTA, and amalgam. Six teeth served as positive and negative controls. All root surfaces, except the ending part, were covered with two layers of nail polish. The roots were then stored in 2% methylene blue for 72 hours and embedded in polyester resin. The teeth were sectioned buccolingually and maximum extent of dye penetration was evaluated through a stereomicroscope. Statis-tical analysis was carried out by one way ANOVA and Tukey test.Results: Biocalex showed significantly less leakage compared to the other three materials P<0.05. White MTA showed significantly lower amount of leakage as Compared to gray MTA and amalgam P<0.05.Conclusion: The findings of this study showed that retrograde filling with Biocalex can achieve proper sealing ability and this material can be used as an alternative for MTA and amalgam.

  3. Comparative evaluation of the accuracy of two electronic apex locators in determining the working length in teeth with simulated apical root resorption: An in vitro study

    Science.gov (United States)

    Saraswathi, Vidya; Kedia, Archit; Purayil, Tina Puthen; Ballal, Vasudev; Saini, Aakriti

    2016-01-01

    Introduction: Accurate determination of working length (WL) is a critical factor for endodontic success. This is commonly achieved using an apex locator which is influenced by the presence or absence of the apical constriction. Hence, this study was done to compare the accuracy of two generations of apex locators in teeth with simulated apical root resorption. Materials and Methods: Forty maxillary central incisors were selected and after access preparation, were embedded in an alginate mold. On achieving partial set, teeth were removed, and a 45° oblique cut was made at the apex. The teeth were replanted and stabilized in the mold, and WL was determined using two generations of apex locators (Raypex 5 and Apex NRG XFR). Actual length of teeth (control) was determined by visual method. Statistical Analysis: Results were subjected to statistical analysis using the paired t-test. Results: Raypex 5 and Apex NRG was accurate for only 33.75% and 23.75% of samples, respectively. However, with ±0.5 mm acceptance limit, they showed an average accuracy of 56.2% and 57.5%, respectively. There was no significant difference in the accuracy between the two apex locators. Conclusion: Neither of the two apex locators were 100% accurate in determining the WL. PMID:27656055

  4. Effect of different final irrigating solutions on smear layer removal in apical third of root canal: A scanning electron microscope study

    Directory of Open Access Journals (Sweden)

    Sayesh Vemuri

    2016-01-01

    Full Text Available Aim: The aim of this in vitro study is to compare the smear layer removal efficacy of different irrigating solutions at the apical third of the root canal. Materials and Methods: Forty human single-rooted mandibular premolar teeth were taken and decoronated to standardize the canal length to 14 mm. They were prepared by ProTaper rotary system to an apical preparation of file size F3. Prepared teeth were randomly divided into four groups (n = 10; saline (Group 1; negative control, ethylenediaminetetraacetic acid (Group 2, BioPure MTAD (Group 3, and QMix 2 in 1 (Group 4. After final irrigation with tested irrigants, the teeth were split into two halves longitudinally and observed under a scanning electron microscope (SEM for the removal of smear layer. The SEM images were then analyzed for the amount of smear layer present using a three score system. Statistical Analysis: Data are analyzed using the Kruskal-Wallis test and Mann-Whitney U-test. Results: Intergroup comparison of groups showed statistically significant difference in the smear layer removal efficacy of irrigants tested. QMix 2 in 1 is most effective in removal of smear layer when compared to other tested irrigants. Conclusion: QMix 2 in 1 is the most effective final irrigating solution for smear layer removal.

  5. Comparison of apical leakage of endodontic sealers AH Plus, Sealapex, Sealer 26 and Endofill through clearing teeth

    Directory of Open Access Journals (Sweden)

    Cristina REISS-ARAÚJO

    2009-03-01

    Full Text Available Introduction and objective: The aim of this study was to analyze theinfiltration of the sealers AH Plus®, Sealapex®, Sealer 26® and Endofill®,using clearing teeth technique. Material and methods: Fifty single-rooted teeth had its crowns removed and canals prepared by the Oregon modified technique. After the chemical-mechanical preparation, the root canals were filled with gutta-percha and four different sealers:group I: AH Plus®; group II: Sealapex®; group III: Sealer 26® and group IV: Endofill®. The others two groups of five teeth each served as positive and negative control groups. After filling, teeth remained for 60 days in saline solution 0.9%, simulating oral conditions. Following this stage,teeth were covered by three layers of nail polish, immersed in nankin ink and stored in a stove under 37ºC for 48 hours. After this period of time, the samples were washed in current water for 24 hours, the nail varnishes were removed with bistoury blade and the clearing technique was applied to evaluate the results. Results and conclusion: The results showed insignificant differences between the materials tested and so a similar behavior in the apical marginal infiltration.

  6. Contributions of Individual Amino Acid Residues to the Endogenous CLV3 Function in Shoot Apical Meristem Maintenance in Arabidopsis

    Institute of Scientific and Technical Information of China (English)

    Xiu-Fen Song; Da-Li Yu; Ting-Ting Xu; Shi-Chao Ren; Peng Guo; Chun-Ming Liu

    2012-01-01

    As a peptide hormone,CLV3 restricts the stem cell number in shoot apical meristem (SAM) by interacting with CLV1/CLV2/CRN/RPK2 receptor complexes.To elucidate howthe function of the CLV3 peptide in SAM maintenance is established at the amino acid (AA) level,alanine substitutions were performed by introducing point mutations to individual residues in the peptide-coding region of CLV3 and its flanking sequences.Constructs carrying such substitutions,expressed under the control of CLV3 regulatory elements,were transformed to the clv3-2 null mutant to evaluate their efficiencies in complementing its defects in SAMs in vivo.These studies showed that aspartate-8,histidine-11,glycine-6,proline-4,arginine-1,and proline-9,arranged in an order of importance,were critical,while threonine-2,valine-3,serine-5,and the previously assigned hydroxylation and arabinosylation residue proline-7 were trivial for the endogenous CLV3 function in SAM maintenance.In contrast,substitutions of flanking residues did not impose much damage on CLV3.Complementation of different alanine-substituted constructs was confirmed by measurements of the sizes of SAMs and the WUS expression levels in transgenic plants.These studies established a complete contribution map of individual residues in the peptide-coding region of CLV3 for its function in SAM,which may help to understand peptide hormones in general.

  7. PEG-mediated osmotic stress induces premature differentiation of the root apical meristem and outgrowth of lateral roots in wheat.

    Science.gov (United States)

    Ji, Hongtao; Liu, Ling; Li, Kexue; Xie, Qingen; Wang, Zhijuan; Zhao, Xuhua; Li, Xia

    2014-09-01

    Water stress is one of the major environmental stresses causing growth retardation and yield loss of plants. In the past decades, osmotic adjustment, antioxidant protection, and stomatal movement have been extensively studied, but much less attention has been paid to the study of root system reprogramming to maximize water absorption and survival under water stress. Here, it is shown that polyethylene glycol (PEG)-simulated mild and moderate osmotic stress induced premature differentiation of the root apical meristem (RAM). It is demonstrated that RAM premature differentiation is a conserved adaptive mechanism that is widely adopted by various plants to cope with osmotic stress simulated by PEG 8000, and the occurrence of RAM premature differentiation is directly related to stress tolerance of plants. It is shown that the osmotic stress-induced premature differentiation caused growth cessation of primary roots allowing outgrowth of lateral roots. This work has uncovered a key mechanism for controlling the plastic development of the root system by which plants are capable of survival, growth, or reproduction under water stress.

  8. Basal and apical regulation of VEGF-A and placenta growth factor in the RPE/choroid and primary RPE

    Science.gov (United States)

    Kaya, Leyla; Flach, Janina; Lassen, Jens; Treumer, Felix; Roider, Johann

    2015-01-01

    Purpose Members of the vascular endothelial growth factor (VEGF) family are strongly involved in pathological processes in the retina, such as age-related macular degeneration and diabetic retinopathy. Cells of the retinal pigment epithelium (RPE) constitutively secrete VEGF-A, and the secretion of placental growth factor (PlGF) has also been described. RPE cells are strongly polarized cells with different secretome at the apical and basal side. In this study, we evaluated the basal and apical regulation of VEGF-A and PlGF secretion in RPE/choroid explants and primary RPE cells. Methods RPE/choroid tissue explants were prepared from porcine eyes and cultivated in modified Ussing chambers, separating apical (RPE) and basal (choroid) supernatant. Primary RPE cells were also prepared from porcine eyes and cultivated on Transwell plates. Explants and cells were treated with inhibitors for VEGFR-2 (SU1498), p38 (SB203580), and the transcription factors nuclear factor-kappa B (NF-κB) and SP-1 (mithramycin), respectively. VEGF-A and PlGF content was evaluated with enzyme-linked immunosorbent assay (ELISA). In addition, western blots were performed. Results In the RPE/choroid, VEGF-A can initially be found on the apical and basal sides with significantly more pronounced secretion on the basal side. VEGF-A secretion is differentially regulated on the apical and basal sides, with the inhibition of SP-1 and NF-κB showing strong effects apically and basally after 24 h and 48 h, the inhibition of p38 displaying its effect mainly on the basal side with some effect apically after 48 h, and the inhibition of VEGFR-2 reducing the secretion of VEGF only on the apical side at 24 h and 48 h. In the RPE cell culture, similar effects were found, with inhibition of NF-κB or SP-1 displaying a strong decrease in VEGF-A on both sides, and p38 inhibition displaying only an inhibitory effect on the basal side. In contrast, an apical effect of VEGFR-2 inhibition was not found. However, the

  9. Analysis of dental root apical morphology: a new method for dietary reconstructions in primates.

    Science.gov (United States)

    Hamon, NoÉmie; Emonet, Edouard-Georges; Chaimanee, Yaowalak; Guy, Franck; Tafforeau, Paul; Jaeger, Jean-Jacques

    2012-06-01

    The reconstruction of paleo-diets is an important task in the study of fossil primates. Previously, paleo-diet reconstructions were performed using different methods based on extant primate models. In particular, dental microwear or isotopic analyses provided accurate reconstructions for some fossil primates. However, there is sometimes difficult or impossible to apply these methods to fossil material. Therefore, the development of new, independent methods of diet reconstructions is crucial to improve our knowledge of primates paleobiology and paleoecology. This study aims to investigate the correlation between tooth root apical morphology and diet in primates, and its potential for paleo-diet reconstructions. Dental roots are composed of two portions: the eruptive portion with a smooth and regular surface, and the apical penetrative portion which displays an irregular and corrugated surface. Here, the angle formed by these two portions (aPE), and the ratio of penetrative portion over total root length (PPI), are calculated for each mandibular tooth root. A strong correlation between these two variables and the proportion of some food types (fruits, leaves, seeds, animal matter, and vertebrates) in diet is found, allowing the use of tooth root apical morphology as a tool for dietary reconstructions in primates. The method was then applied to the fossil hominoid Khoratpithecus piriyai, from the Late Miocene of Thailand. The paleo-diet deduced from aPE and PPI is dominated by fruits (>50%), associated with animal matter (1-25%). Leaves, vertebrates and most probably seeds were excluded from the diet of Khoratpithecus, which is consistent with previous studies. PMID:22553124

  10. Apices of maxillary premolars observed by swept source optical coherence tomography

    Science.gov (United States)

    Ebihara, Arata; Iino, Yoshiko; Yoshioka, Toshihiko; Hanada, Takahiro; Sunakawa, Mitsuhiro; Sumi, Yasunori; Suda, Hideaki

    2015-02-01

    Apicoectomy is performed for the management of apical periodontitis when orthograde root canal treatment is not possible or is ineffective. Prior to the surgery, cone beam computed tomography (CBCT) examination is often performed to evaluate the lesion and the adjacent tissues. During the surgical procedure, the root apex is resected and the resected surface is usually observed under dental operating microscope (DOM). However, it is difficult to evaluate the details and the subsurface structure of the root using CBCT and DOM. A new diagnostic system, swept source optical coherence tomography (SS-OCT), has been developed to observe the subsurface anatomical structure. The aim of this study was to observe resected apical root canals of human maxillary premolars using SS-OCT and compare the findings with those observed using CBCT and DOM. Six extracted human maxillary premolars were used. After microfocus computed tomography (Micro CT; for gold standard) and CBCT scanning of the root, 1 mm of the apex was cut perpendicular to the long axis of the tooth. Each resected surface was treated with EDTA, irrigated with saline solution, and stained with methylene blue dye. The resected surface was observed with DOM and SS-OCT. This sequence was repeated three times. The number of root canals was counted and statistically evaluated. There was no significant difference in the accuracy of detecting root canals among CBCT, DOM and SS-OCT (p > 0.05, Wilcoxon test). Because SS-OCT can be used in real time during surgery, it would be a useful tool for observing resected apical root canals.

  11. Evaluation of apical extrusion of debris during ultrasonic versus rotary instrumentation

    Directory of Open Access Journals (Sweden)

    Araquam, Karolline Rodrigues

    2009-01-01

    Full Text Available Objetivo: O objetivo deste estudo foi comparar a extrusão apical de debris durante a instrumentação rotatória versus ultra-sônica de canais radiculares. Metodologia: A amostra constituiu-se de 20 pré-molares inferiores com dimensões radiculares similares. Para coleta do material extruído apicalmente durante a instrumentação endodôntica, foram fixados recipientes de resina acrílica na superfície externa das raízes. Todos os dentes tiveram os terços cervical e médio dos canais radiculares preparado com brocas Gates-Glidden. Após odontometria, a instrumentação apical foi realizada com sistema ultra-sônico ou sistema rotatório (n=10/grupo. Os recipientes de resina foram pesados antes e após a instrumentação e a diferença de peso foi considerada a quantidade de material extruído. Os dados foram analisados por teste de Mann-Whitney, ao nível de significância de 0,05. Resultados: Houve grande variabilidade de quantidade de material extruído para ambas as técnicas de instrumentação, com valores de 0,0009 a 0,0860 g. Não houve diferença estatisticamente significante entre os dois grupos (P>0. 05. Conclusão: Pode-se concluir que ambas as técnicas de instrumentação testadas, com ultra-som ou sistema rotatório, apresentaram extrusão apical de debris em quantidade semelhante

  12. Analysis of dental root apical morphology: a new method for dietary reconstructions in primates.

    Science.gov (United States)

    Hamon, NoÉmie; Emonet, Edouard-Georges; Chaimanee, Yaowalak; Guy, Franck; Tafforeau, Paul; Jaeger, Jean-Jacques

    2012-06-01

    The reconstruction of paleo-diets is an important task in the study of fossil primates. Previously, paleo-diet reconstructions were performed using different methods based on extant primate models. In particular, dental microwear or isotopic analyses provided accurate reconstructions for some fossil primates. However, there is sometimes difficult or impossible to apply these methods to fossil material. Therefore, the development of new, independent methods of diet reconstructions is crucial to improve our knowledge of primates paleobiology and paleoecology. This study aims to investigate the correlation between tooth root apical morphology and diet in primates, and its potential for paleo-diet reconstructions. Dental roots are composed of two portions: the eruptive portion with a smooth and regular surface, and the apical penetrative portion which displays an irregular and corrugated surface. Here, the angle formed by these two portions (aPE), and the ratio of penetrative portion over total root length (PPI), are calculated for each mandibular tooth root. A strong correlation between these two variables and the proportion of some food types (fruits, leaves, seeds, animal matter, and vertebrates) in diet is found, allowing the use of tooth root apical morphology as a tool for dietary reconstructions in primates. The method was then applied to the fossil hominoid Khoratpithecus piriyai, from the Late Miocene of Thailand. The paleo-diet deduced from aPE and PPI is dominated by fruits (>50%), associated with animal matter (1-25%). Leaves, vertebrates and most probably seeds were excluded from the diet of Khoratpithecus, which is consistent with previous studies.

  13. In vitro analysis of the cement film thickness of two endodontic sealers in the apical region

    Directory of Open Access Journals (Sweden)

    Garcia Lucas da Fonseca

    2009-01-01

    Full Text Available Objectives : The objective of the present study was to evaluate in vitro film thickness of two endodontic sealers containing epoxy-resin and zinc-oxide-eugenol, respectively in the apical region of the root canal system. Materials and Methods : A total of 20 palatine roots of the first maxillary molars were submitted to instrumentation up to a #40 file by the step-back technique and irrigated with 2 ml of NaOCl after each change of file. The roots were divided at random into two groups of 10 elements; one group was sealed with the Sealer 26® cement and the other one with the EndoFill® cement using the classical technique. The roots were abraded in the apical region until exposure of the filling and cut crosswise at 3 mm to obtain samples. The samples were analyzed by optic microscopy with 40X magnification. The images obtained were recorded using the Adobe Premiere 5.1® software and submitted to morphometric analysis using an integration grid that permitted the quantification of the area filled with the sealer or gutta-percha, and eventual empty spaces. Results : Statistical analysis of the data (Kruskal-Wallis test, P < 0.05 revealed no significant differences between the epoxy-resin-based cement Sealer 26® (47.85% and the zinc- oxide- eugenol-based cement EndoFill® (54.16%. Conclusion : We conclude that the two sealers tested showed a similar behavior regarding the cement film thickness in the apical region.

  14. The phospholipid flippase ATP8B1 mediates apical localization of the cystic fibrosis transmembrane regulator.

    Science.gov (United States)

    van der Mark, Vincent A; de Jonge, Hugo R; Chang, Jung-Chin; Ho-Mok, Kam S; Duijst, Suzanne; Vidović, Dragana; Carlon, Marianne S; Oude Elferink, Ronald P J; Paulusma, Coen C

    2016-09-01

    Progressive familial intrahepatic cholestasis type 1 (PFIC1) is caused by mutations in the gene encoding the phospholipid flippase ATP8B1. Apart from severe cholestatic liver disease, many PFIC1 patients develop extrahepatic symptoms characteristic of cystic fibrosis (CF), such as pulmonary infection, sweat gland dysfunction and failure to thrive. CF is caused by mutations in the cystic fibrosis transmembrane conductance regulator (CFTR), a chloride channel essential for epithelial fluid transport. Previously it was shown that CFTR transcript levels were strongly reduced in livers of PFIC1 patients. Here we have investigated the hypothesis that ATP8B1 is important for proper CFTR expression and function. We analyzed CFTR expression in ATP8B1-depleted intestinal and pulmonary epithelial cell lines and assessed CFTR function by measuring short-circuit currents across transwell-grown ATP8B1-depleted intestinal T84 cells and by a genetically-encoded fluorescent chloride sensor. In addition, we studied CFTR surface expression upon induction of CFTR transcription. We show that CFTR protein levels are strongly reduced in the apical membrane of human ATP8B1-depleted intestinal and pulmonary epithelial cell lines, a phenotype that coincided with reduced CFTR activity. Apical membrane insertion upon induction of ectopically-expressed CFTR was strongly impaired in ATP8B1-depleted cells. We conclude that ATP8B1 is essential for correct apical localization of CFTR in human intestinal and pulmonary epithelial cells, and that impaired CFTR localization underlies some of the extrahepatic phenotypes observed in ATP8B1 deficiency. PMID:27301931

  15. Evidence for an apical Na-Cl cotransporter involved in ion uptake in a teleost fish

    Science.gov (United States)

    Hiroi, J.; Yasumasu, S.; McCormick, S.D.; Hwang, P.-P.; Kaneko, T.

    2008-01-01

    Cation-chloride cotransporters, such as the Na+/K +/2Cl- cotransporter (NKCC) and Na+/Cl - cotransporter (NCC), are localized to the apical or basolateral plasma membranes of epithelial cells and are involved in active ion absorption or secretion. The objectives of this study were to clone and identify 'freshwater-type' and 'seawater-type' cation-chloride cotransporters of euryhaline Mozambique tilapia (Oreochromis mossambicus) and to determine their intracellular localization patterns within mitochondria-rich cells (MRCs). From tilapia gills, we cloned four full-length cDNAs homologous to human cation-chloride cotransporters and designated them as tilapia NKCC1a, NKCC1b, NKCC2 and NCC. Out of the four candidates, the mRNA encoding NKCC1a was highly expressed in the yolk-sac membrane and gills (sites of the MRC localization) of seawater-acclimatized fish, whereas the mRNA encoding NCC was exclusively expressed in the yolk-sac membrane and gills of freshwater-acclimatized fish. We then generated antibodies specific for tilapia NKCC1a and NCC and conducted whole-mount immunofluorescence staining for NKCC1a and NCC, together with Na+/K+-ATPase, cystic fibrosis transmembrane conductance regulator (CFTR) and Na+/H+ exchanger 3 (NHE3), on the yolk-sac membrane of tilapia embryos acclimatized to freshwater or seawater. The simultaneous quintuple-color immunofluorescence staining allowed us to classify MRCs clearly into four types: types I, II, III and IV. The NKCC1a immunoreactivity was localized to the basolateral membrane of seawater-specific type-IV MRCs, whereas the NCC immunoreactivity was restricted to the apical membrane of freshwater-specific type-II MRCs. Taking account of these data at the level of both mRNA and protein, we deduce that NKCC1a is the seawater-type cotransporter involved in ion secretion by type-IV MRCs and that NCC is the freshwater-type cotransporter involved in ion absorption by type-II MRCs. We propose a novel ion-uptake model by MRCs in

  16. Correlative Analysis of [Ca2+]C and Apical Secretion during Pollen Tube Growth and Reorientation

    OpenAIRE

    Coelho, Pedro Castanho; Malhó, Rui

    2006-01-01

    The maintenance of a cytosolic free calcium gradient (Ca2+]c) and vesicle secretion in the apex of pollen tubes is essential for growth. It has been postulated that high [Ca2+]c levels promote and confine vesicle fusion with the apical plasma membrane and in this study we performed a correlative analysis of both events using specific fluorescent dyes and confocal scanning microscopy. [Ca2+]c was imaged with Calcium Green-1 10 kDa dextran (CG-1) while secretory events were followed with FM1–43...

  17. Changes of Root Length and Root-to-Crown Ratio after Apical Surgery

    DEFF Research Database (Denmark)

    von Arx, Thomas; Jensen, Simon S; Bornstein, Michael M

    2015-01-01

    the length of apicectomy and calculated the loss of root length and changes of RCR after apical surgery. METHODS: In a prospective clinical study, cone-beam computed tomography scans were taken preoperatively and postoperatively. From these images, the crown and root lengths of 61 roots (54 teeth in 47.......58 ± 1.43 mm (relative to the CBL). This amounted to a loss of 33.2% of clinical and 26% of anatomic root length. There was an overall significant difference between the tooth groups (P

  18. The Domain Specificity of Academic Emotional Experiences

    Science.gov (United States)

    Goetz, Thomas; Frenzel, Anne C.; Pekrun, Reinhard; Hall, Nathan C.

    2006-01-01

    The authors analyzed the domain specificity of emotions and focused on experiences of enjoyment, anxiety, and boredom in the domains of mathematics, Latin, German, and English. On the basis of assumptions in R. Pekrun's (2000; in press) control-value theory and findings of pilot studies, the authors hypothesized the existence of a largely…

  19. Endodontic management of immature teeth with spontaneous apical closure and periapical lesions: case series and review of the literature.

    Science.gov (United States)

    Çalışkan, Mehmet Kemal; Kaval, Mehmet Emin

    2015-08-01

    Spontaneous apical closure in non-vital immature teeth has been rarely encountered and outcome of non-surgical endodontic treatment of related teeth associated with periapical lesions has not yet been adequately elucidated. The aim of this article was to report endodontic management of spontaneous apical closure of infected untreated immature teeth with periapical lesions and to review previously proposed mechanisms for the development of spontaneous hard tissue barrier. Three patients were referred at different time intervals to the endodontic clinic for treatment of their maxillary anterior incisors with acute or chronic apical periodontitis. Dental histories indicated that related teeth had been subjected to trauma approximately 12-18 years previously. Radiographically, the involved teeth exhibited incomplete root formation with spontaneous apical closure and were associated with an apical radiolucency. After biomechanical preparation, calcium hydroxide paste was applied and was changed once or twice within 3 months. All canals were then filled with gutta-percha and AH Plus and the follow-up period was 16-50 months; both clinical and radiographic examinations revealed adequate function, the absence of clinical symptoms and significant healing of the periapical radiolucency.

  20. Fragment Propagation and Colonization Ability Enhanced and Varied at Node Level after Escaping from Apical Dominance in Submerged Macrophytes

    Institute of Scientific and Technical Information of China (English)

    Jinhui Jiang; Shuqing An; Changfang Zhou; Baohua Guan; Zhiyi Sun; Ying Cai; Fude Liu

    2009-01-01

    Aquatic plants develop strong fragment propagation and colonization ability to endure the natural disturbances. However,detailed research of ability to endure the natural disturbances has been lacking to date. Therefore, reproduction (shoot) and colonization (root) of shoot fragments of Potamogeton crispus L. with or without apices were investigated for the effect of apical dominance, and the growth of decapitated shoot fragments at three lengths (2, 4, 6cm) was compared. Meanwhile,fragment propagation at levels of bud position was studied for bud position effect after escaping from apical dominance.The results showed significant increases occurred in the outgrowth of lateral branches on fragments decapitated compared with the fragments with apices, implying that apical dominance exists. Different lengths of fragments showed little difference in biomass allocations, but significant differences were noted in their propagation. Meanwhile, the effect of bud position was verified, due to the significant difference of average reproduction per node among the three length groups. Thus, the present study has made progress in the current understanding of aquatic plant dispersion among natural systems and contributes to improve methods of in vitro propagation for re-implantation purposes.